RLI 281 25 DECEMBER 2012 RESEARCH LIBRARY ISSUES: A QUARTERLY REPORT FROM ARL, CNI, AND SPARC Universal Design, Inclusive Design, Accessibility, and Usability D igital content cannot be assumed to be accessible to assistive or adaptive technologies such as text-to-speech screen readers. Early PDFs that still populate library websites and databases were often image-only files, and some software will not recognize columns in articles nor translate charts, graphs, and figures into something meaningful and accurate. Crowded database search screens with image-only buttons for critical navigation or access to full text have similarly been problematic. But even as some problems are solved, others are created if accessibility is not an upfront consideration. E-books are a key example. The primary factors that have excluded visually impaired users from the e-book revolution are the use of file formats that cannot be read by the technologies used by the blind DRM schemes that prevent such technology from accessing these files and proprietary e-book reading software or devices that the blind cannot use. E-books, which hold the promise of truly equal access by the blind to all printed information, are in serious danger of becoming an even greater barrier to such access.47 In a Canadian study of students using screen readers to use popular library databases, the authors found significant barriers to discovery and full-text access. Studies have shown that information literacy is a critical element in fostering problem solving and independent learning in higher education students…The question this study asked was whether the barriers in database design can affect a student's information gathering process. The results would point to yes, the first step in information literacy— the ability to critically locate and select appropriate articles is being compromised. The students in our study were forced to abandon articles because of technological barriers and this limited the amount of resources they could use to write their assignments. Only the intervention of a librarian or peer would have allowed them to continue in locating the full text and reading the article. Their self-efficacy as independent learners is challenged every time they encounter an unreadable PDF or take up to eight hours to find four articles.48 Universal design is a concept that originated in architecture and the built environment. Perhaps its most cited example and metaphor is the curb cut, mandated and designed for wheelchairs but appreciated by anyone with a stroller, shopping cart, bicycle, or rolling suitcase. "Similarly, text captions of speech in videos were intended for individuals who are hard of hearing or deaf, but the primary users are patrons at noisy sports bars and fitness centers and spouses who wish to continue watching television while their spouse sleeps. In addition to being more sustainable, integrated accessibility features are also far less costly in the long run and, according to a study by Microsoft, are used by up to 67% of users."49 Retrofitting technology, like architecture, is far more expensive than planning for inclusion by design. "The cost of accessibility when carefully planned and designed is almost zero…However, often extreme
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Transition & Turnaround Management,
Corporate Renewal, and Equity Capital Investment Firm
Summary -- Overview -- Contact
Transition Managers & Investors
Strategic Management Partners has substantial experience advising corporations and individuals on the strategic and mechanical issues of corporate development, operating management, turnarounds for asset recovery, and equity capital investing. Our principal has over 25 years experience in P/L Management, Strategic Planning and Repositioning, M&am;A for Strategic Advantage, Finance, Investing, Raising Funds, Sales/Business Development, Building Selling and Marketing Teams, and Operational Auditing = In Public & Private companies = In healthy and crisis situations. Also see About the Principal
Overview -- Features & Benefits
Bringing success to the processes of transition, change, renewal and investing.
The renewal and investment processes can have predictable outcomes.
Your Requirement
Multi Functional Background Our principal started in operational auditing, proceeded to financial analysis, business development and sales, general profit center and company management of private and public companies. He now specializes in turning around and investing in troubled companies. He is past chairman of the Turnaround Management Association [8,500 members in the U.S. and around the world].
Demonstrated Turnaround Achievements We are a turnaround management firm started in 1988, while this M&A, start-up and turnaround experience dates back to the late 1970's. We have been involved in asset recovery totaling $85 million, and have consulted with and operationally run public and private companies in turnaround situations. Named [twice] to Top 12 Outstanding Turnaround Firms by Turnarounds & Workouts Magazine. Honored by the Turnaround Management Association as a recipient of their award for Outstanding Contribution to the Corporate Renewal Profession.
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New Business Development We can account for new business totaling $670 million systems integration plus $150 million commercial.
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Track Record in Acquisitions, Divestitures, and Licensing Agreements We have been involved in over 40 acquisitions, divestitures worth over $780 million in a diverse set of industries. Much of this work was combining companies into a larger entity for growth or resale.
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Operating Turnarounds and Raising Funds While the majority of work has been based in the U.S. our principal has run company subs in the UK, Germany; has acquisition and business development experience in Canada, Europe, Central Europe, Far East, Middle East; has spent eight months raising an $80 million privatization restructuring fund in Slovenia and consulting to EBRD and The World Bank on turnarounds and privatization; and has taught turnaround management and equity investing techniques to Russian privatization and bankruptcy officials in Moscow, Ljubljana and Toronto.
Operational Effectiveness We are comfortable managing at the CEO level, companies ranging from $10 to $100 million. We have many vignettes that describe success stories. We invite you to look further, and draw your own conclusions.
We have developed management processes that focus on various phases and actions during the turnaround cycle and investing activity. These structured and orderly approaches allow us a high rate of success in crisis, turnaround and workout engagements; and particularly in investing for returns. Contact us to discuss the detailed methodology and how this can work for you.
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The Anti-Sanctuary-Cities Bill That Outlawed Dissent
A federal court enjoined much of a Texas law that punished officials who dared "endorse" the view that its provisions were harmful to public safety.
Garrett Epps
A woman who is seeking asylum has her fingerprints taken by a U.S. Customs and Border patrol officer at a pedestrian port of entry from Mexico to the United States in McAllen, Texas, May 10, 2017. Carlos Barria / Reuters
Last week, in City of El Cenizo v. Texas, a federal district court enjoined much of Texas's new anti-"sanctuary city" law, SB 4, from taking effect. That bill stirred eerie echoes of the American past; I heard faint tones of Abraham Lincoln's pro-slavery rival Stephen A. Douglas in the stated intent of its sponsor.
Start with SB 4. In its main features, it told Texas localities, universities, or officials—on pain of fines and even jail time—that they could not stop local peace officers from investigating the immigration status of those they detain and notifying federal authorities; forbade the same localities and officials to limit "the enforcement of immigration laws;" and instructed local peace officers to provide "enforcement assistance" to federal immigration authorities. In addition, localities would be required to obey "immigration detainer requests," which are administrative requests from immigration authorities to keep individuals in jail even after charges have been dropped so they can decide whether to deport them.
Texas Governor Greg Abbott signed SB 4 in May, and proclaimed, "Texas has now banned sanctuary cities."
On August 30—one day before SB 4 was to take effect—federal Judge Orlando Garcia of the Western District of Texas issued a preliminary injunction against most of the law. The detainer provision, he held, probably violates the Fourth Amendment's bar on "unreasonable" arrest and detention. The "cooperation" clause, he held, almost certainly violates the federal immigration code, which, unlike SB 4, allows cooperation with local law enforcement only under strict conditions—including that all cooperation be under the direct authority of the attorney general, not local immigration officials.
But, in the most interesting part of the opinion, Garcia held that the ban on any "policy" that "prohibits or materially limits the enforcement of immigration laws" is so broadly written that it would bar local officials from even criticizing state immigration policy—and thus almost certainly violates the First Amendment.
That brings us to Douglas, Lincoln's foe in the 1858 Lincoln-Douglas debates. Douglas emerged victorious in the Illinois Senate race against Lincoln, then lost to him in the presidential election two years later. The "Little Giant" (5'4") stood beside the 6'4" Lincoln and held his foe's stovepipe hat at the Inauguration. Three months later he died of typhoid fever.
In the antebellum years, Douglas tried to thread the needle between the Northern and Southern wings of the Democratic Party, but, as the dispute heated up, he moved closer to what anti-slavery forces called "the Slave Power." After John Brown's anti-slavery raid on Harper's Ferry in 1859, Douglas made his "Sedition Law" speech on the Senate floor. Southern states, citing the danger of "servile insurrection," had long banned any internal criticism of slavery. Now Douglas proposed making the ban national, through a federal statute that would "suppress all conspiracies and combinations in the several states with intent to invade a state, or molest or disturb its government, its peace, its citizens, its property, or its institutions." In other words, to guarantee the safety of the slave states, Douglas proposed outlawing the anti-slavery movement—and the Republican Party.
"The Harper's Ferry crime," he told senators, "was the natural, logical, inevitable result of the doctrines and teachings of the Republican Party." Lincoln, he said, had warned that a "house divided against itself cannot stand." Republican Senator William H. Seward proclaimed the clash between slavery and free labor "an irrepressible conflict" that would leave the nation all free or all slave.
Republicans were preaching disunion, Douglas said. The solution was to stop their mouths through "indictments and convictions" that "will make such examples of the leaders of these conspiracies as will strike terror upon the hearts of the others, and then there will be the end of this crusade."
Lincoln warned in his Cooper Union speech that "Senator Douglas' new sedition law" would suppress "all declarations that slavery is wrong, whether made in politics, in presses, in pulpits, or in private," but the bill never advanced.
The Sedition Bill controversy is a particularly inglorious chapter in Douglas's checkered career; but in factual terms he was right. An institution like human slavery can, in the end, be maintained only if government silences not only slaves but free people. By designating some humans as less than human—as holders, in Chief Justice Roger B. Taney's phrase, of "no rights which the white man was bound to respect"—American society authorized warfare against its own people, and the brutality of that internal war inevitably spurred a reaction. The slaves bore the brunt of the war; but with the passage of the Fugitive Slave Act of 1850, it spread to ensnare free states. The Supreme Court's Dred Scott decision served notice that even the concept of a "free state" might soon be struck down. Controls on speech would be the logical next step.
America's war on its own people could not be won unless all dissent, indeed all freedom, was eventually crushed.
This takes us back to Garcia's opinion in City of El Cenizo. He pointed out that SB 4 forbids local governments or any officer or employee of a local government to "adopt, enforce, or endorse" a policy against cooperation with immigration authorities. Violators can be hauled into court by any citizen who disagrees with them. Courts finding a violation must assess fines of up to $25,000 a day against the locality—or the official. And any official violating the "endorsement" ban is to be removed from office by the court.
The bill's sponsor, Texas Senator Charles Perry, explained during debate that "endorse" means "support, identify with, and it is, it becomes part of our DNA [sic], or culture to endorse that, that we believe enough in it to put our name on it." If, for example, a sheriff or police chief were to write a newspaper article criticizing SB 4, he added, "it's effectively creating a culture of contempt or noncompliance," and would therefore run afoul of the law. As for free speech, "I don't know that that's a free speech issue if you've been elected to uphold the law. You don't get the right as a free speech [sic] to go out and not uphold the law."
Garcia found two kinds of fault with the "endorse" language. The first is that, if it means what Perry says it means, it is a "content-based restriction on speech." In this case, it is what First Amendment lawyers call "viewpoint based"—as Garcia wrote, under SB 4 "one viewpoint on local immigration policy is banned and the opposite viewpoint is permitted." That's a big First Amendment no-no. But beyond that, the statute is unconstitutionally vague—"a person of ordinary intelligence has no guidance whatsoever as to what is prohibited," he wrote. Vagueness is also a First Amendment red light, because it can intimidate speakers who want to engage in fully protected speech, and empower prosecutors to move unpredictably against those they dislike. In the case of SB 4, Garcia wrote, "Prosecution to remove a local official from office will end up being selective, arbitrary, discriminatory, and in violation of First Amendment rights." But "under the American system, local elected officials, and persons who are appointed or employed by local governmental entities are expected to engage in open, robust debate on such issues, as such debates lead to a more informed electorate."
Garcia quoted Abbott, for example, as saying that when the bill takes effect, "I'm putting the hammer down ... We are going to be asserting fines. We're going to be seeking court orders that could lead to putting these people behind bars, the officials who are violating their oath of office." Was he threatening to jail local officials—by coincidence Democrats—for maintaining forbidden policies, or simply for opposing the state's policy? Beyond that, Garcia noted, the state of Texas had filed suit against Travis County—Austin is the county seat—for violating SB 4 even before the law took effect. In its complaint, the state charged that "several localities and civil rights groups … were 'publicly hostile to cooperation with federal immigration enforcement.'"
That suit was mercifully dismissed in August. But the state's strategy is instructive. One of the groups Texas sued along with Travis County was the Mexican American Legal Defense and Education Fund—one of the oldest and most respected Latino civil-rights groups in the country. I am quite sure that MALDEF has never refused an ICE detainer or refused to allow its peace officers to conduct immigration raids. (MALDEF has no jail, and no police force.) Its offense, the complaint stated, was that it "publicly declared imminent legal action against Texas." (Texas was shamed into dropping MALDEF as a defendant even before the federal judge tossed the whole case.) It was as if Texas had sued the NAACP for opposing segregation.
Of course, that's exactly what Southern states like Virginia did during the civil-rights era. That was another time of crisis, and the response of the segregated authorities was to attack the opposition. The state of Texas's demand for silence and obedience echoes that dark time.
Immigration generally, and the Trump administration's crackdown on the undocumented population in particular, are bitterly dividing both Texas and the United States as a whole. Much of the conflict pits urban areas against suburbs and rural ones; the cities where the undocumented live don't want to drive their people into the shadows. Their officials believe that public services—such as civil justice, police protection, labor laws, public health, and consumer protection—can't be effectively provided unless everyone can access them without fear of arrest or deportation.
In the past six months, the national disquiet over immigration has become a war against a new enemy: 11.3 million people within America's borders. The Constitution's guarantees of due process, equal protection, and security from unreasonable seizure or cruel and unusual punishment are being stripped from 3 percent of the U.S. population.
That war escalated sharply on Tuesday, when Attorney General Jeff Sessions announced that the administration is unwinding the "deferred action" program. The 800,000 "dreamers" in DACA—brought to the U.S. as children, raised among Americans—are now the enemy too. These are children, parents, brothers, sisters, co-workers, friends, and neighbors of American citizens. Whether at work, in emergency rooms, in courtrooms, at schools and colleges, or in their homes, unless Congress acts to protect them, they will be liable to arrest without warning and, often with only minimal due process, expulsion from the country.
Polls suggest that most citizens oppose wholesale deportation, and instead support giving law-abiding unauthorized immigrants a means to legalize their status, and eventually become citizens. As the war escalates, the outcry from local communities has begun. It seems unlikely this Congress will restore DACA; if it does not, the outcry seems likely to become louder. The war is probably unwinnable; it certainly is if Americans who oppose it are silenced. Courts do not save civil liberty when government is determined to stamp it out; for each citizen whose rights are vindicated in court, a dozen will remain silent out of fear. That is the meaning of "chilling effect," and a chill wind indeed is blowing in the U.S. today.
"It is proper," James Madison wrote in another context, "to take alarm at the first experiment on our liberties." If citizens, and courts, do not act, Americans should not be surprised to find Texas-style gags around their mouths.
Garrett Epps is a contributing editor for The Atlantic. He teaches constitutional law and creative writing for law students at the University of Baltimore. His latest book is American Justice 2014: Nine Clashing Visions on the Supreme Court.


Tag Archives: greg schiano
For National Football Authority, we examine the nitpicking tendencies of new Buccaneers head coach Greg Schiano and consider what they may mean for the future of the team. Will Schiano bring much needed order to the locker room? Or will his style prove overbearing? Click here to read all about it.
Buccaneers head coach Greg Schiano, via nfl.com
Filed under Football Relativity, National Footbal Authority, NFL coaches
Tagged as Football Relativity, greg schiano, NFL, NFL coaches, nfl head coaches, tampa bay buccaneers
Buccaneers give Greg Schiano the old college try
We have been commenting on head-coaching hires in our annual Football Relativity new coaches post, but the Tampa Bay Buccaneers' decision to hire former Rutgers head coach Greg Schiano was notable enough that we wanted to make it its own post. Below are our thoughts; you can see how we think the hire compares to others this offseason in the accumulated post.
New Buccaneers head coach Greg Schiano, via nj.com
The Buccaneers, apparently entranced by Jim Harbaugh's first-season success, first chased Oregon's Chip Kelly before landing Schiano from Rutgers. Schiano did a remarkable job of taking Rutgers from being the dregs of college football to being respectable, although he couldn't take the final step to a BCS bowl out of the Big East. Still, he has a solid resume that includes NFL experience as a defensive backs coach with the Bears. He is well respected, and Bill Belichick's public respect undoubtedly helped Schiano land the job in Tampa Bay. Now he must show that he can coach, not just recruit. The Bucs have a young roster, and the fact that Tampa Bay has taken a lot of gambles on talented players with questionable character certainly contributed to the 10-game losing streak that cost Raheem Morris his job. Schiano must make the team tougher as he develops the skills of guys like QB Josh Freeman, DE Adrian Clayborn, and MLB Mason Foster. That means Schiano's staff will be of paramount importance. We never love the idea of college coaches going to the pros, and a coach who made his bones as a recruiter the way Schiano did is even more of a question mark. But if Schiano can add toughness, the talent is present for Tampa Bay to tick up quickly.
Filed under Football Relativity, NFL coaches
Tagged as adrian clayborn, chip kelly, Football Relativity, greg schiano, jim harbaugh, josh freeman, mason foster, NFL, NFL coaches, nfl head coaches, raheem morris, tampa bay buccaneers
FR: 2012 Coaching Changes
Each year, we review and compare new head coaches in the NFL. This year's entries:
*Kansas City (Romeo Crennel, who was the interim, replacing Todd Haley)
*Jacksonsville (Mike Mularkey, replacing interim Mel Tucker, who replaced Jack Del Rio)
*St. Louis (Jeff Fisher, replacing Steve Spagnuolo)
*Miami (Joe Philbin, replacing interim Todd Bowles, who replaced Tony Sparano)
*Oakland (Dennis Allen, replacing Hue Jackson)
*Indianapolis (Chuck Pagano, replacing Jim Caldwell)
*Tampa Bay (Greg Schiano, replacing Raheem Morris)
We put these hires through the theory of relativity. We'll do it on a 10-point scale, with 10 being the best possible hire, and 1 being the worst possible hire.
10 – Jeff Fisher, Rams – In an offseason where many big names circulated around the coaching carousel, Fisher is the one who actually landed. The former Titans coach provided stability for an organization that didn't really have it otherwise in Tennessee, and the results were 142 wins, six playoff appearances, and one AFC championship over 17 years. Fisher never had elite talent, but he always had a physical team that played good defense and ran the ball well. And when he got a quarterback with toughness – as with the late Steve McNair – he won. Now he goes to St. Louis, where he becomes the seventh coach (including interims) since 2005. The Rams desperately need stability, and Fisher brings that. He should help a defense with nice, young front seven pieces play better, and he will set about fixing an offensive line that has struggled despite massive investment in the draft and in free agency. Most of all, his job is to develop a system that allows promising young QB Sam Bradford to prosper. (We covered what Fisher's arrival means to RB Steven Jackson previously in this post.) Fisher may not be a Hall of Fame level coach, but he is a good one, and he should help in St. Louis.
7 – Chuck Pagano, Colts – I don't know why I have such a good feeling about the fit of Pagano and the Colts. Pagano's NFL resume isn't that long – he has spent most of his coaching career in college – and he served as a coordinator for just one year at the NFL level. But his Ravens defense was solid this season, and he certainly had plenty of big personalities to contend with in Baltimore. Now this coaching lifer – who has also been a secondary coach in Cleveland and Oakland – leaps to the big job. When he has been in the media, he has showed personality, and all reports say he was hyper-prepared for his Colts interview. The one potential glitch in this mix is how Pagano will develop a young quarterback – either Andrew Luck or Robert Griffin III – coming in as a rookie. Undoubtedly, the Colts asked that question in the interview, and they must have liked Pagano's answer. And stepping into a situation with a franchise quarterback coming in off the bat is good fortune for Pagano. Plus, the recent history of Ravens defensive coordinators to become head coaches (Marvin Lewis, Rex Ryan for example) is pretty good. His staff will be key, but the early returns on Pagano and the Colts seem very promising.
6 – Mike Mularkey, Jaguars – We discussed the reasons behind hiring Mularkey and what his biggest job in Jacksonville is in this post. We like the move even more now that he has kept Mel Tucker around as defensive coordinator. Ultimately, we like this move more than most second-time coaches. Mularkey is still a good prospect and a worthwhile hire.
New Rams head coach Jeff Fisher. Image via Wikipedia
5 – Dennis Allen, Raiders – The Raiders, who were widely assumed to be importing a Packers assistant now that Reggie McKenzie is the GM, instead hired Broncos defensive coordinator Allen. Allen doesn't have a long resume, but he did a nice job with the Denver defense this year after a few years as the Saints secondary coach. The fact that Allen was hired off John Fox's staff could be a good precedent; a similar thing happened when Jacksonville plucked defensive coordinator Jack Del Rio off Fox's staff after his first year in Carolina. Allen is just 39, but he's obviously a sharp coach, and former players have credited his people skills as well. But the Raiders' culture isn't necessarily one bred for success at this point. There is a commitment to excellence, but there isn't a commitment to the things excellence requires – like discipline, shrewd salary-cap management, and more. McKenzie will start trying to fix those things, but the question is whether being the first coach in the rebuilding process is ideal. Still, Allen inherits a talented roster, and he knows the AFC West. He needs to find a strong offensive voice, but that could still happen. So he has a real shot in his first head-coaching job – which isn't a bad situation at age 39.
4 – Greg Schiano, Buccaneers – The Buccaneers, apparently entranced by Jim Harbaugh's first-season success, first chased Oregon's Chip Kelly before landing Schiano from Rutgers. Schiano did a remarkable job of taking Rutgers from being the dregs of college football to being respectable, although he couldn't take the final step to a BCS bowl out of the Big East. Still, he has a solid resume that includes NFL experience as a defensive backs coach with the Bears. He is well respected, and Bill Belichick's public respect undoubtedly helped Schiano land the job in Tampa Bay. Now he must show that he can coach, not just recruit. The Bucs have a young roster, and the fact that Tampa Bay has taken a lot of gambles on talented players with questionable character certainly contributed to the 10-game losing streak that cost Raheem Morris his job. Schiano must make the team tougher as he develops the skills of guys like QB Josh Freeman, DE Adrian Clayborn, and MLB Mason Foster. That means Schiano's staff will be of paramount importance. We never love the idea of college coaches going to the pros, and a coach who made his bones as a recruiter the way Schiano did is even more of a question mark. But if Schiano can add toughness, the talent is present for Tampa Bay to tick up quickly.
3 – Joe Philbin, Dolphins – Philbin, who spent his entire NFL coaching career with the Packers after joining the team in 2003, was an under-the-radar selection who gained serious momentum with the Packers' offensive explosion this season. Everyone who has worked with Philbin speaks highly of him, both as a strategist and in terms of working with people. If that's the case, then he could end up being a fine selection. But he represents a departure from the offensive system the Dolphins were using, and a transition to the West Coast offense could lead the team downward before it surges. Plus, owner Stephen Ross really wanted a high-profile hire – he chased Jim Harbaugh and Jeff Fisher the last two offseasons – so it's hard to imagine how much rope Philbin will get in Miami. Philbin's a good head-coaching candidate, but this is a strange place for him to land.
1 – Romeo Crennel, Chiefs – We discussed why the Crennel hire is a bad idea in this post.
Tagged as adrian clayborn, andrew luck, baltimore ravens, bill belichick, carolina panthers, chicago bears, chip kelly, chuck pagano, cleveland browns, dennis allen, denver broncos, Football Relativity, greg schiano, hue jackson, indianapolis colts, jack del rio, jacksonville jaguars, jeff fisher, jim caldwell, jim harbaugh, john fox, josh freeman, kansas city chiefs, marvin lewis, mason foster, mel tucker, mike mularkey, new orleans saints, NFL, NFL coaches, nfl head coaches, oakland raiders, raheem morris, reggie mckenzie, Rex ryan, robert griffin iii, romeo crennel, sam bradford, st. louis rams, steve mcnair, steve spagnuolo, steven jackson, tampa bay buccaneers


Activity Title: Infection Prevention & Control in the Wake of COVID-19
The ongoing COVID-19 pandemic has highlighted challenges and opportunities for infection control practices at healthcare facilities around the globe. In this moderated discussion, infection prevention and control experts describe how they responded to the pandemic and what they did to quickly adapt existing healthcare protocols. Speakers will describe how these approaches and the lessons learned from the COVID-19 pandemic can help us better prepare for future outbreaks
Professor Gonzalo Martin Llorens Bearman
MD, MPH, FACP, FSHEA, FIDSA
Gonzalo Bearman is Chair of the Division of Infectious Diseases. He is a graduate of Colgate University (BA), SUNY at Buffalo School of Medicine and Biomedical Sciences (MD) and Columbia University (MPH). Dr. Bearman is Board Certified in Internal Medicine, Infectious Diseases, and General Preventive Medicine and Public Health.
Professor Ziad A. Memish
MD, FRCPC, FRCPE, FRCPL, FACP, FFPH
Ziad Memish is currently senior consultant in infectious diseases and Director of research & Innovation Center at King Saud Medical City, Ministry of Health. Professor at the College of Medicine in Alfaisal University, Riyadh, Saudi Arabia; and Adjunct Professor in the Hubert Department of Global Health, Rollins School of Public Health, Emory University, Georgia, USA. Professor Memish is Board certified by the American Board of Internal Medicine, the American Board of Infectious Diseases as well as a Fellow of the Royal College of Physicians (Canada, Edinburgh and London) and the American College of Physicians.
Professor Michael Stevens
MD, MPH
Mike Stevens, MD, MPH, is a Professor of Internal Medicine in the Division of Infectious Diseases at Virginia Commonwealth University (VCU) in Richmond, VA. He is Director of the Antimicrobial Stewardship Program, an Associate Hospital Epidemiologist, Director of the health system's Travel & Tropical Medicine clinic and the Associate Chair for the Division of Infectious Diseases. He has been an editor on ISID's Guide to Infection Control in the Healthcare Setting since 2013.
Professor Victor Rosenthal
Dr. Rosenthal is specialist in Internal Medicine and in ID. He is certified on Infection Control and Hospital Epidemiology. He was a fellow of ID at University of Wisconsin. He finished post graduate course of the Program of Clinical Effectiveness of Harvard University.
Dr. Michelle Doll
Michelle Doll, MD, MPH is an Assistant Professor of Internal Medicine at Virginia Commonwealth University (VCU) where she is also an Associate Hospital Epidemiologist for the Hospital Infection Prevention Program. She is board certified in Internal Medicine and Infectious Disease.
Professor Shaheen Mehtar
MBBS, FRCPath (Eng), FCPath (SAfrica), MD (Lon)
Shaheen Mehtar is Professor(retired) at the Unit for Infection Prevention and Control (UIPC), Division of Global Health, Faculty of Health Sciences, Stellenbosch University, South Africa. She trained in the United Kingdom in Medical Microbiology, Infectious Disease and Community Health. Following a post as Deputy Director of Public Health in the South Cape Karoo region, she moved to Tygerberg Hospital and Stellenbosch University where she established the Unit of Infection Prevention and Control in 2004.
Professor Folasade Tolulope Ogunsola
MBChB, PhD, FMCPath, FWACP, FNAMed. FAS
Folasade Ogunsola is a Professor of Clinical Microbiology at the College of Medicine University of Lagos, Nigeria. She was a founding member of the Nigerian Society for Infection Control in 1998 and has assisted in setting up infection control programs in institutions in the country. She was the Chair of the Infection Control Committee and of the Antibiotic policy committee of the Lagos University Teaching Hospital.
Upon completion of this module, participants should be able to::
Discuss how the ongoing COVID-19 pandemic has highlighted both challenges and opportunities for infection control practices at healthcare facilities around the globe
Discuss how infection prevention and control experts responded to the pandemic and what they did to quickly adapt existing healthcare protocols
Describe how these approaches and the lessons learned from the COVID-19 pandemic can help us better prepare for future outbreaks.
The target audience for this module is physicians, nurses, public health officials, researchers, immunization officers, and other health professionals.
ISID Guide to Infection Control in the Healthcare Setting (open access): https://isid.org/guide/
Infection Control Africa Network (ICAN): http://www.icanetwork.co.za
International Nosocomial Infection Control Consortium (INICC): http://www.inicc.org
World Health Organization: Infection Prevention and Control Resources: https://www.who.int/teams/integrated-health-services/infection-prevention-control
US CDC: Infection Control Guidance for Healthcare Professionals about Coronavirus (COVID-19). https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control.html
Prof. Gonzalo Bearman, Prof. Sade Ogunsola, Prof. Ziad Memish, Prof. Shaheen Mehta, Prof. Victor Rosenthal, and Dr. Michael Stevens have no potential conflicts of interest in relation to this program/presentation.
Dr. Michelle Doll:
Receipt of grants/research support: Molnlycke Healthcare
Infection Prevention & Control in the Wake of COVID-19


Charlotte Tilbury's $164 Mystery Box Is Worth More Than $300 — And You Can Shop It Early
Here's how you can snag one with SEVEN full-size products.
by Margaret Blatz
Courtesy of Charlotte Tilbury
There's some great news coming from Charlotte Tilbury, and it's a mystery. Well, kind of. The cult-favorite brand is releasing a Charlotte Tilbury Mystery Box on Monday, Aug. 9, and it's full of the lust-worthy, high-quality beauty products you've come to expect from the brand. The best news of all? Elite Daily readers get a special treat: If you're reading this, you can shop the Mystery Box early on the Charlotte Tilbury website here. Although no one can say everything in the Mystery Box — hence the "mystery" — here are the details we do know.
Valued at $328, the Mystery Box is actually a steal, retailing for only $164, or 50% off. I can give you a little clue as to what you'll receive if you snag a box. Each Charlotte Tilbury Mystery Box includes the brand's award-winning Magic Cream Moisturizer ($64, Charlotte Tilbury) and a shimmering, silky Walk of No Shame Luxury Palette ($53, Charlotte Tilbury). These two bestsellers will come alongside a whopping five other products, for a total of seven full-size products in the box. Rest assured, though, the remainder of the contents are guaranteed to be just as luxurious, so you don't even have to cross your fingers.
We only include products that have been independently selected by Elite Daily's editorial team. However, we may receive a portion of sales if you purchase a product through a link in this article.
Charlotte's Beauty Secrets Mystery Box
See On Charlotte Tilbury
Going from being a celebrated makeup artist to creating her own celebrated brand, Tilbury has focused her beauty lines on products that make you both feel and look your best. Her decades at the forefront of the industry have put her at the cutting edge of the beauty world. So, whether you like a tried, true, and timeless approach to your makeup or something more eccentric and bold, this Mystery Box is going to have just the products you need. (And, I mean, who couldn't use a little more Magic Cream in their lives, truly?)
Walk of No Shame Luxury Palette
As if this news wasn't exciting enough, Charlotte Tilbury is also having its Summer Sale right now. Until Aug. 16, the brand is offering 40% off a bursting selection of the brand's best makeup and skin care products. It's truly the season of deals at Charlotte Tilbury.
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You Didn't Know Hummus Was Your Favorite Milkshake Flavor ... Until Now
Hummus Milkshakes
16 December, 2018 by Najla Moussa
Hummus is an Arabic dish made of chickpea paste. The word 'hummus' means chickpea in Arabic. Case closed.
But whatever anyone else says about it or where they think it's from, there isn't a house in the Levant region that doesn't serve this creamy goodness – at breakfast, lunch and dinner. It's just a versatile staple and it's yummy enough to be eaten at all meals. It's used as a dip, with several topping variations; it's used as a base spread on sandwich; and sometimes it's just eaten straight out of a bowl.
But Hummus shakes? I'm pretty sure Middle Eastern grandmothers are turning in their graves at the thought. But The Hummus & Pita Co., in Greenwich, New York, doesn't stop at making hummus the way Arabs prepare it. Nah. They've gone way out of left field with their Hummus creations.
The shake was created by the founder of Hummus & Pita Co., Dave Pesso, who told Insider that his company likes to "think out of the box," and that he was interested in creating a hummus shake that was delicious, yet vegan.
After tweaking it and offering free samples to lots of people who thought they were being "Punk'd" because they couldn't believe how good it was, he decided it was time to start selling it.
The basic ingredients are: hummus, dates, bananas, almond milk and Tahini. Then he's got the flavors: Strawberry, Chocolate, Pistachio, and Butter Pecan. Incidentally, he also makes hummus deserts in three flavors: chocolate, cookie dough and cake batter.
We don't know whether to laugh or cry. But if it ever comes to town, I know I'm standing in line to try it.
Image Source: POPSUGAR Photography
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Colorado Man Takes Aurora to the Movies
On Saturday, August 11, Jason and his friends will stand in black T-shirts in front of five theaters in the Denver area, hanging out a little goodness to a whole lot of people.
Patience Salgado, Contributor
Kindnessgirl.com
08/10/2012 11:37am EDT | Updated December 6, 2017
Sometimes it's hard to find a light in the dark, especially in places where fear lurks. We struggle to understand such darkness, like what occurred in Aurora and Oak Creek.
Jason Cole, a father and tech software executive from Louisville, Colorado, saw the dark unfolding around him. He was determined to do something about it; to take the power of fear away, and place the power back into the hands of the people.
The Friday after the tragedy, Jason decided he wanted to take the Greater Denver area back to the movies. He told us his message is simple: "Tonight, the movie's on us. Go, enjoy. This isn't a fundraiser; it's not a memorial service. Some jerk tried to steal a night of fun from all of us. Tonight, we're giving it back."
Within a week, Cole had enough money gathered from family, friends, sponsors and strangers to take 1,000 people to the movies. By Thursday, he added 300 more tickets.
On Saturday, August 11, Jason and his friends will stand in black T-shirts in front of five theaters in the Denver area, handing out a little goodness to a whole lot of people.
In Jason's words, we all have a choice.
You can choose the light or the dark, and you change the world with each choice you make. I said that, in a world where one person can traumatize an entire region with his actions, it's up to the rest of us to choose the light.
Cole and his friends are inviting folks all over the country to join him this Saturday by simply buying a ticket for others while at their local movie theaters. He suggests going to the movies with a group on August 11, scatter people throughout the line, and have each person pay for the people behind them.
For more information about how you can participate, head over to Take Back the Movies here.
photo courtesy of Rachel Cole
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Florida Gay Rights Activist Found Dead In Landfill, Prompting Homicide Probe


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Fast Molecular-Dynamics Simulation for Ferroelectric Thin-Film Capacitors Using a First-Principles Effective Hamiltonian
Takeshi Nishimatsu1,2 Umesh V. Waghmare3 Yoshiyuki Kawazoe2 David Vanderbilt1 1Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, NJ 08544-8019
2Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577, Japan
3Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560 064, India
A newly developed fast molecular-dynamics method is applied to BaTiO3 ferroelectric thin-film capacitors with short-circuited electrodes or under applied voltage. The molecular-dynamics simulations based on a first-principles effective Hamiltonian clarify that dead layers (or passive layers) between ferroelectrics and electrodes markedly affect the properties of capacitors, and predict that the system is unable to hop between a uniformly polarized ferroelectric structure and a striped ferroelectric domain structure at low temperatures. Simulations of hysteresis loops of thin-film capacitors are also performed, and their dependence on film thickness, epitaxial constraints, and electrodes are discussed.
pacs:
77.80.Dj, 77.80.Fm, 64.70.Nd
Ferroelectric thin films are beginning to see wide-ranging applications, for example in multilayer capacitors, nonvolatile FeRAMs Scott (2000) , and nanoactuators. There is strong pressure to reduce the sizes of such thin-film structures. In recent years, the preparation of oxide thin films by low-temperature non-equilibrium techniques such as molecular beam epitaxy and pulsed-laser deposition have attracted a great deal of attention, as they enable finely controlled growth of epitaxial thin films Choi et al. (2004) .
It is well known that the properties of ferroelectric capacitors are highly influenced by the properties of the interface between the ferroelectrics and the electrodes. For example, the fatigue of ferroelectric capacitors is associated with the appearance of dead layers (or passive layers) near the electrodes, Drougard and Landauer (1959); Miller et al. (1990); Lemanov and Yarmarkin (1996); Jin and Zhu (2002) and imperfect electrodes cannot fully screen the polarization of ferroelectrics Mehta et al. (1973); Dawber et al. (2003) , leading to a finite depolarization field in the ferroelectric film. However, the nanosize effects and temperature dependences of ferroelectric capacitor hysteresis, polarization switching, and dynamics of domain wall motion remain poorly known. Experimentally, in situ observations are difficult. Theoretically, the long-range Coulomb interaction limits the size and time of molecular-dynamics (MD) simulations, and it has been unclear how to include surface effects and depolarization fields caused by interface structures.
In 1994, King-Smith and Vanderbilt studied the total-energy surface for zone-center distortions of perovskite-type ferroelectric oxides ABO3 (A is a monovalent or divalent cation and B is a penta- or tetravalent metal) at zero temperature using first-principles calculations with ultrasoft-pseudopotentials and a plane-wave basis set. King-Smith and Vanderbilt (1994) Starting from the full symmetric cubic perovskite structure, they define the displacements vτα of atoms τ (=A, B, OI, OII, OIII) in the Cartesian directions α(=x,y,z) along the Γ15 soft-mode normalized direction vectors ξα as
vα=⎛⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜⎝vAαvBαvOIαvOIIαvOIIIα⎞⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟⎠=uαξα=uα⎛⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜⎝ξAαξBαξOIαξOIIαξOIIIα⎞⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟⎠ , (1)
with the scalar soft-mode amplitude uα. Under the condition that the strain components ηi (i=1, …, 6; Voigt notation; η1=e11, η4=e23) minimize the total energy for each u=(ux,uy,uz), they expressed the total energy as
Etot=E0+κu2+α′u4+γ′(u2xu2y+u2yu2z+u2zu2x) , (2)
where u2=u2x+u2y+u2z, E0 is the total energy for the cubic structure, κ is half the eigenvalue of the soft mode, and α′ and γ′ are the constants determined from coupling constants between atomic displacements and strains. Their expression properly describes the coupling of polar atomic-displacement and strain degrees of freedom.
In 1994-1997, Zhong, Vanderbilt, and Rabe Zhong et al. (1994, 1995) and Waghmare and Rabe Waghmare and Rabe (1997) expanded Eq. (2) from a mean-field framework to a local-mode framework, replacing u by {u}, where the braces {} denote a set of u in a simulation supercell, as
Etot=Vself({u})+Vdpl({u})+Vshort({u})+Velas(η1,⋯,η6)+Vint({u},η1,⋯,η6) . (3)
Here Vself, Vdpl, Vshort, Velas, and Vint are a local-mode self-energy, a long-range dipole-dipole interaction, a short-range interaction between soft-modes, an elastic energy, and an interaction between the local modes and local strain, respectively. They employed Eq. (3) as an effective Hamiltonian for {u} in the supercell, performed Monte-Carlo simulations, and demonstrated the ability to describe the phase transitions of bulk ferroelectrics. The coarse-graining that reduces the 15-dimensional atomic displacement vector vτα to a 3-dimensional local soft-mode amplitude vector uα in each unit cell was shown to be a good approximation. However, the computation of Vdpl was still time-consuming, owing to the long-range Coulomb interaction, thus limiting system size and simulation time that could be handled in practical simulations.
In 2003, Waghmare, Cockayne, and Burton introduced a technique to decrease the computational time for Vdpl (or forces exerted on {u}). Waghmare et al. (2003) Direct calculation of the forces in real space requires a computational time proportional to N2, i.e., O(N2), where N is the supercell size (N=Lx×Ly×Lz). It decreases to O(NlogN) if one calculates the forces in reciprocal space using fast-Fourier transform (FFT) methods. This acceleration in computational speed enabled us to perform MD simulations on {u} in a large supercell, and was applied to bulk relaxor ferroelectrics Waghmare et al. (2003); Burton et al. (2005) .
Here, we explain how the fast MD method for simulating a first-principles effective Hamiltonian can be applied to study ferroelectric thin-film capacitor structures with short-circuited electrodes or external electric fields. This new MD method can simulate perovskite-type ferroelectric thin-film capacitors with dead layers and consequent depolarization fields. The high speed of this MD method enables us to simulate a ferroelectric material for a realistic system size (up to 100 nm) and a realistic time span (> 1 ns).
In the next section, we explain the formalism of the new MD-simulation method for thin-film capacitors. Results of simulations of BaTiO3 bulk and thin-film capacitors are shown in Sec. III. In subsection III.1, we confirm the reliability of our MD program by simulating thermal properties of bulk BaTiO3. The advantage of this MD method compared to the Monte-Carlo method is also discussed. In subsection III.2, we perform heating-up and cooling-down simulations for thin-film BaTiO3 capacitors with perfect and imperfect electrodes. Thickness dependence of simulated striped domain structures in thin-film capacitors with imperfect electrodes are analyzed in detail. We have already reported some simulated results of thin-film capacitors of this subsection and determined thermal properties in Ref. [ Paul et al., 2007 ] briefly. In subsection III.3, newly obtained simulated results of hysteresis loops of thin-film capacitors are reported. In Sec. IV, we summarize the paper.
We named our MD program feram and distribute it as free software through http://loto.sourceforge.net/feram/.
Ii Formalism and method of calculation
ii.1 Effective Hamiltonian
The effective Hamiltonian used in the present MD simulations is basically the same as that in Ref. [ Waghmare et al., 2003 ]. Here, we present the Hamiltonian with a notation similar to that in Ref. [ Zhong et al., 1995 ] as
Heff=M∗dipole2∑R,α˙u2α(R)+M∗acoustic2∑R,α˙w2α(R)+Vself({u})+Vdpl({u})+Vshort({u})+Velas,homo(η1,⋯,η6)+Velas,inho({w})+Vcoup,homo({u},η1,⋯,η6)+Vcoup,inho({u},{w})−Z∗∑RE⋅u(R) , (4)
where u=u(R) and w=w(R) are, respectively, the local soft-mode amplitude vector and the local acoustic displacement vector of the unit cell at R, the α component of R runs over
Rα=0, a0, 2a0, ⋯ (Lα−1)a0 , (5)
η1,⋯,η6 are the homogeneous strain components, and M∗dipole and M∗acoustic are the effective masses for u and w, respectively. Note that u can also be considered as the optical displacement, in contrast to the acoustic displacement w, or the dipole moment Z∗u, where Z∗ is the Born effective charge associated with the soft mode. In the effective Hamiltonian (4), external electric field E is taken into account through its vector product with each dipole moment Z∗u.
To determine the effective mass M∗dipole, let ϵτα(k,i) be a mass-weighted i-th eigenvector of the phonon dynamical matrix at wavevector k. Its eigenvalue {ω(k,i)}2 is the corresponding phonon frequency. Moreover, let dτα(k,i)=ϵτα(k,i)/√Mτ be an atomic displacement vector, which is normalized as ∑α,τ{dτα(k,i)}2=1 by adjusting the norm of ϵ(k,i). Here, Mτ is the mass of atom τ. Generally, the effective mass of a phonon is k- and mode-dependent:
M∗(k,i)=∑α,τ{dτα(k,i)}2Mτ . (6)
However, as an approximation, we have to employ a unique effective mass for dipoles in the MD simulation. Thus using the steepest descent Γ15 soft-mode normalized direction vectors ξz=(0.20, 0.76,−0.21,−0.21,−0.53) and ξx=ξy=0 from Ref. [ Zhong et al., 1995 ], for BaTiO3, we set M∗dipole as
M∗dipole=∑τ{ξτz}2Mτ=39.0amu . (7)
It should be mentioned that ξτz is not equal to the dτα of the Γ15 soft-mode of phonon, because MA, MB, and MO are not identical.
The local-mode self-energy Vself({u}) is
Vself({u})=N∑i=1{κ2u2(Ri)+αu4(Ri)+γ[u2y(Ri)u2z(Ri)+u2z(Ri)u2x(Ri)+u2x(Ri)u2y(Ri)]} , (8)
where u2(Ri)=u2x(Ri)+u2y(Ri)+u2z(Ri).
The long-range dipole-dipole interaction Vdpl({u}) is
Vdpl({u})=12N∑i=1∑αN∑j=1∑βuα(Ri)Φαβ(Rij)uβ(Rj) , (9)
Φαβ(Rij)=Z∗2ϵ∞∑n′δαβ−3(ˆRij+n)α(ˆRij+n)β|Rij+n|3 , (10)
ϵ∞ is the optical dielectric constant (or refractive index squared), δαβ is the Kronecker delta, a hat indicates a unit vector, n is the supercell lattice vector
nα=⋯, −2Lαa0, −Lαa0, 0, Lαa0, 2Lαa0, ⋯ , (11)
and a0 is the equilibrium lattice constant. In Eq. (10), ∑′ indicates that the summation does not include terms for which Rij=n=0.
We take account of short-range interactions between the optical displacements u(R) up to third nearest neighbor (3nn) as
Vshort({u})=12N∑i=1∑α3nn∑j∑βuα(Ri)Jij,αβuβ(Rj) , (12)
where Jij,αβ is the short-range interaction matrix, which can be classified into 7 independent interaction parameters, Zhong et al. (1995) Jij,αβ=±jk (k=1,⋯,7).
In practice, κ2u2i in Eq. (8), Eq. (9), and Eq. (12), in which uα is quadratic, are gathered and calculated in reciprocal space as
Vquad({u})=12∑k∑α,β˜u∗α(k)˜Φquadαβ(k)˜uβ(k), (13)
where ˜uα(k) is the Fourier transform
˜uα(k)=∑Ruα(R)exp(−ik⋅R) , (14)
of uα(R), ˜Φquadαβ(k) is similarly the Fourier transform of the quadratic interaction matrix (which is only calculated once at the beginning of simulation Waghmare et al. (2003) ), and k is a reciprocal vector in the first Brillouin zone of the unit cell such as
kα=−Lα−12Lα2πa0, ⋯, −1Lα2πa0, 0, 1Lα2πa0, ⋯, 122πa0 . (15)
The homogeneous elastic energy Velas,homo(η1,⋯,η6) is
Velas,homo(η1,⋯,η6) = N2B11(η21+η22+η23) (16)
+ NB12(η2η3+η3η1+η1η2)
+ N2B44(η24+η25+η26) ,
where B11, B12, and B44 are the elastic constants expressed in energy unit (B11=a30C11, B12=a30C12, and B44=a30C44).
The inhomogeneous elastic energy Velas,inho({w}) is also calculated in reciprocal space as
Velas,inho({w})=12∑k∑α,β˜w∗α(k)˜Φelas,inhoαβ(k)˜wβ(k). (17)
For the force constant matrix ˜Φelas,inhoαβ(k), we employed the long-wavelength approximation. For instance, the diagonal part is
˜Φelas,inhoxx(k)=1N[k2xB11+k2yB44+k2zB44] , (18)
and the off-diagonal part is
˜Φelas,inhoxy(k)=1N[kxkyB12+kxkyB44] . (19)
The coupling between {u} and homogeneous strain is the same as that given in Ref. [ King-Smith and Vanderbilt, 1994 ], i.e.,
Vcoup,homo({u},η1,⋯,η6)=12∑R6∑i=16∑j=1ηiCijyj(R) . (20)
Here, y1(R) = u2x(R), y2(R) = u2y(R), y3(R) = u2z(R), y4(R) = uy(R)uz(R), y5(R) = uz(R)ux(R), and y6(R) = ux(R)uy(R),
C=⎛⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜⎝B1xxB1yyB1yy000B1yyB1xxB1yy000B1yyB1yyB1xx0000002B4yz0000002B4yz0000002B4yz⎞⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟⎠ , (21)
and B1xx, B1yy, and B4yz are the coupling coefficients defined in Ref. [ King-Smith and Vanderbilt, 1994 ].
The coupling between {u} and inhomogeneous strain is also calculated in reciprocal space as
Vcoup,inho({u},{w})=12∑k∑α6∑i=1˜wα(k)˜Bαi(k)˜yi(k) , (22)
where ˜wα(k) and ˜yi(k) are the Fourier transforms of wα(R) and yi(R), respectively. For the 3×6 coupling matrix B(k), we again employed the long-wavelength approximation
˜B(k)=1N⎛⎜⎝kxB1xxkxB1yykxB1yy02kzB4yz2kyB4yzkyB1yykyB1xxkyB1yy2kzB4yz02kxB4yzkzB1yykzB1yykzB1xx2kyB4yz2kxB4yz0⎞⎟⎠ . (23)
In the present MD simulations of BaTiO3, the parameters from Refs. [ Zhong et al., 1994 ] and [ Zhong et al., 1995 ], which are determined by first-principles calculations, are employed. As mentioned in Refs. [ Zhong et al., 1994 ] and [ Zhong et al., 1995 ], this parameter set leads to an underestimation of the Curie temperature TC. To correct this underestimation, we follow these references in applying a negative pressure of p=−5.0 GPa in all simulations.
ii.2 Molecular Dynamics
MD simulations with the effective Hamiltonian of Eq. (4) are performed in the canonical ensemble using the Nosé-Poincaré thermostat. Bond et al. (1999) This simplectic thermostat is so efficient that we can set the time step to Δt=2 fs. In our present simulations, we thermalize the system for 40,000 time steps, after which we average the properties for 10,000 time steps.
In Fig. 1 we roughly illustrate how to calculate the forces exerted on uα(R) with ˜Φquadαβ(k) in Eq. (13) and how the time evolution is simulated. First, uα(R) is FFTed to ˜uα(k), the force ˜Fα(k)=−∑β˜Φquadαβ(k)˜uβ(k) is calculated in reciprocal space, and then the force in real space is obtained by the inverse FFT of ˜Fα(k). In practice, updates of uα(R) and ˙uα(R)=∂∂tuα(R) are processed in the manner of the Nosé-Poincaré thermostat.
Figure 1: Simplified flow chart for calculating forces on uα(R). Fast Fourier transform (FFT) and inverse FFT (IFFT) enable rapid calculation of long-range dipole-dipole interactions.
The homogeneous strain components η1,⋯,η6 are determined by solving
at each time step according to {u} so that η1,⋯,η6 minimize Velas,homo(η1,⋯,η6)+Vcoup,homo({u},η1,⋯,η6). While the local acoustic displacement wα(R) could be treated as dynamical variables using the effective mass M∗acoustic, we have instead chosen to integrate out these variables in a manner similar to the treatment of the homogeneous strain. That is, wα(R) is determined so that Velas,inho({w})+Vcoup,inho({u},{w}) becomes minimum at each time step according to uα(R). Technically, the minimization is performed by solving the linear set of equations
˜Φelas,inho(k)˜w(k)+˜B(k)˜y(k)=0 (25)
for each k in reciprocal space.
ii.3 Ferroelectric Thin Films
If a ferroelectric thin film is placed in isolation in vacuum without electrodes as depicted in Fig. 2(a), its spontaneous polarization P=(Px,Py,Pz), which is represented by a thick arrow in the figure, induces charges ±σind=±Pz at both surfaces, and the induced charges cause a full depolarization field in the thin film, Ed=−4πσindˆz=−4πPzˆz. On the other hand, if the ferroelectric thin film is placed between short-circuited perfect electrodes as depicted in Fig. 2(b), the induced charges are fully canceled by free charges σfree arising at both surfaces of the electrodes, Ed=−4π(σind+σfree)ˆz=0. This geometric circumstance can be simulated with the doubly periodic supercell as depicted in Fig. 2(c), because the two electrodes act as two electrostatic mirrors facing each other, and the mirrors make oppositely charged infinite mirror images beyond the electrodes.
We can also introduce dead layers of thickness d between the ferroelectric thin film and electrodes by constraining the local soft-mode amplitudes to vanish (u=0) in these layers, as illustrated in Fig. 2(d). With the dead layers, the infinite mirror images beyond the electrodes become ll+d more sparse than images of the without-dead-layer configuration. Consequently, the free charges arising at the electrode surfaces decrease to σfree=−ll+dσind, where l is the ferroelectric film thickness. This simulates short-circuited imperfect electrodes resulting in a depolarization field of
Ed=−4πdl+dPzˆz . (26)
We can also use a doubly periodic supercell with dead layers for this case. Physically, the depolarization field of Eq. (26) can arise either from the presence of a dead layer in the ferroelectric near the interface, or from imperfect screening at the metal electrode, or both. We can define an effective screening length for each of these effects, and we interpret the "dead-layer thickness" d of our model as corresponding to the sum of these two physical screening lengths. The screening length associated with the electrode interface appears in Eq. (16) of Ref. [ Mehta et al., 1973 ] and Eq. (1) of Ref. [ Dawber et al., 2003 ] and is discussed for the SrRuO3/BaTiO3 interface in Refs. [ Sai et al., 2005 ], [ Kim et al., 2005 ], and [ Gerra et al., 2006 ]. Therefore, while the model does not explicitly incorporate information about the interface screening, this information is effectively included in the definition of the total screening length d in our model. Thus, for example, simulations at constant d for various film thicknesses can give the thickness dependence of the properties of capacitors with a certain interface structure.
Figure 2: Schematic illustrations of ferroelectric thin films of thickness l unit cells (here l=2). (a) Isolated thin film in vacuum. (b) Thin film sandwiched between short-circuited perfect electrodes. Doubly periodic boundary conditions for simulations of films sandwiched between perfect and imperfect short-circuited electrodes are depicted in (c) and (d), respectively. Horizontal thick lines marked with "E" represent the electrostatic mirrors used to model electrodes. They are a distance d/2 away from the ferroelectric film surface (d=0 in (c), d=1 in (d)). Each thin arrow represents a local dipole within a unit cell (a3=3.94 Å3) of the BaTiO3 crystal. Thick dashed lines enclose the periodic cell used for simulations.
In the present MD simulations, the local soft-mode amplitude vectors u in dead layers are fixed to zero by the infinitely large mass. This infinitely-large-mass trick is congenial to the Nosé-Poincaré thermostat for maintaining the Nosé-Poincaré Hamiltonian at zero. Moreover, this treatment also has another advantage in that the short-range interactions between the surfaces of ferroelectric thin film and the electrodes are automatically truncated.
The depolarization field Ed increases the total energy of the ferroelectric thin film by −P⋅Ed=4πdl+dP2z. To avoid forming a depolarization field in ferroelectric thin films, it is known that the films often develop striped domain structures. Kittel (1946); Fong et al. (2004); Bratkovsky and Levanyuk (2000, 2001) The introduction of the striped domain structure can eliminate some part of the energy increase 4πdl+dP2z, because Pz becomes zero on average. However, the striped domain structure involves an energy cost in the short-range interaction Vshort({u}), because it has domain boundaries between which u has opposite direction ±z. The shorter the wavelength λ of the striped domain structure, the weaker the depolarization field, but the higher the short-range interaction energy. The ground state of a ferroelectric thin film will be decided by a competition between the long-range dipole-dipole interactions which favor a short-period domain structure, and domain-wall energy that arises from the short-range interactions and favors a uniformly polarized structure or a longer-period striped structure. In some previous works Lai et al. (2006, 2007a, 2007b) , the imperfect screening was mimicked with a parameter. On the other hand, our method with doubly periodic boundary condition does not require any parameters, because the effect of imperfectness of electrodes is automatically and implicitly included in the long-range dipole-dipole interaction Vdpl({u}).
Iii Results and Discussion
iii.1 Bulk BaTiO3
We first check the reliability of our MD program by comparing results of our simulations for bulk BaTiO3 with earlier work based on the same effective Hamiltonian Zhong et al. (1994, 1995) . We used a system size of Lx×Ly×Lz=16×16×16 and small temperature steps in heating-up (+5 K/step) and cooling-down (−5 K/step) simulations, with initial configuration generated randomly: ⟨uα⟩=0.07 \AA and ⟨u2α⟩−⟨uα⟩2=(0.02 \AA)2. We have also checked that there was no dependence of results of these simulations on initial configurations. The temperature dependence of the homogeneous strain components (see Fig. 3), which are the secondary order parameters of ferroelectric phase transitions, exhibits the correct sequence of phase transitions in BaTiO3 known experimentally.
Figure 3: Average homogeneous strains exx, eyy, and ezz as a function of temperature in heating-up (+5 K/simulation, solid lines) and cooling-down (−5 K/simulation, dashed lines) simulations for a 16×16×16 supercell. Strains are measured relative to the LDA minimum-energy cubic structure with lattice constant 3.948 Å.
Even under the negative pressure p=−5.0 GPa, the paraelectric to ferroelectric transition temperature TC is underestimated at around 320 K in comparison with the experimental value of TC=408 K. Our estimates of TC's agree fairly well with the ones reported in Ref. [ Zhong et al., 1995 ]. The relatively weak first-order nature of the cubic-to-tetragonal phase transition in comparison with the first-order tetragonal-to-orthorhombic and orthorhombic-to-rhombohedral phase transitions is evident in the width of the temperature intervals of hysteresis (see Fig. 3). We note that the ability to simulate time-dependent phenomena is one of advantages of MD simulations compared to Monte-Carlo simulations.
iii.2 BaTiO3 ferroelectric thin-film capacitors
We now simulate and analyze the behavior of epitaxially grown films of BaTiO3 on GdScO3 substrates. Choi et al. (2004) In our simulations, we represent this with 1% in-plane biaxial compressive strain by maintaining the homogeneous strain η1=η2=−0.01 and η6=0. In other words, we maintained the average lattice constants a and b at 0.99a0 and angle γ at 90∘. We use supercell sizes of Lx×Ly×Lz=32×32×2(l+d) and 40×40×2(l+d) and simulate ferroelectric layers of thickness l sandwiched between two short-circuited electrodes with (d=1) and without (d=0) dead layers. This is accomplished through use of doubly periodic boundary conditions as explained earlier.
Both the heating-up and cooling-down simulations are started with an initial configuration of ⟨ux⟩=⟨uy⟩=0, ⟨uz⟩=0.07 \AA and ⟨u2α⟩−⟨uα⟩2=(0.02 \AA)2. In the cooling-down simulations, which start at a sufficiently high temperature, the initial configuration changes to an unpolarized one (⟨uz⟩=0) during thermalization. We monitor the temperature dependence of ⟨uα⟩ and ⟨u2α⟩ for thin films with thicknesses l=15, 31, 127, and 255 with dead layers d=1 and a thin film with thickness l=32 without dead layers (d=0) (see Fig. 4 and animations in the EPAPS EPA ). The behavior of the film with no dead layer is the same in heating and cooling simulations. In contrast, for the films with a dead layer (d=1), the transition behavior exhibited by ⟨uz⟩=0 is rather different in heating and cooling simulations, although the temperature dependence of ⟨u2z⟩ is almost the same in both the kinds of simulations.
Figure 4: ⟨uz⟩ of heating-up (solid lines) and cooling-down (dashed lines) molecular-dynamics simulations of BaTiO3 thin-film capacitors with short-circuited electrodes under 1% in-plane biaxial compressive strain for (a) thickness l=15 layer with dead layer d=1, (b) l=31 with d=1, (c) l=127 with d=1, (d) l=255 with d=1, and (e) l=32 without dead layer (d=0). √⟨u2z⟩ are also plotted in (a)-(e). In (c)-(e), heating-up √⟨u2z⟩ and cooling-down √⟨u2z⟩ are almost identical. √⟨u2x⟩ is plotted only in (e), because the behaviors of √⟨u2x⟩ and √⟨u2y⟩ are essentially identical in cases (a)-(e) (for both heating-up and cooling-down). Supercells are of size 32×32×2(l+d). Animations of these cooling-down and heating-up simulations are also available in the EPAPS EPA .
In the heating-up simulations, the discontinuity in ⟨uz⟩ as a function of temperature marks a transition from a ferroelectric state with almost uniform out-of-plane polarization (Fig. 5(a)) to one with a striped domain structure (Fig. 5(b) and (c)). We find that this transition temperature, TS(l,d=1), exhibits a strong dependence on size l. We note that this transition is missing in the cooling-down simulations; just above TS, striped domain structures appear and the stripes remain and be frozen at T<TS. The temperature TC(l,d=1) at which √⟨u2z⟩(T) exhibits a change in its slope marks another transition, namely from a striped domain phase to a paraelectric phase. TC(l,d=1) depends relatively weakly on the film thickness.
Figure 5: Snapshots at T=100 K in heating-up ((a)) and cooling-down ((b) and (c)) simulations of ferroelectric thin-film capacitors of l=15 with d=1. (a) and (b) are horizontal slices. (c) is a vertical cross section. Points of snapshots are indicated with "X" marks in Fig. 4(a). In horizontal slices, the +z-polarized and −z-polarized sites are denoted by □ and ■, respectively. In vertical cross sections, the dipole moments of each site are projected onto the xz-plane and indicated with arrows. Layers which do not have arrows are dead layers.
It should be mentioned that the results of heating-up simulations with a phase transition from the single domain state to the striped domain state at TS below TC agree with thermodynamical treatment of ferroelectric capacitors with dead layers by Chensky and Tarasenko. Chensky and Tarasenko (1982)
For films with d=1, TS is 150 and 210 K for l=15 and l=31 respectively, which is lower than the bulk transition temperature (TC≈320 K). However, for d=1 films with l=127 and l=255, TS is enhanced to 520 and 610 K respectively, well above the bulk TC. In the infinite thickness limit (l→∞), it appears that TS(l,d=1) tends to the TC of thick films with no dead layer (d=0), since TC is 650 K for l=32 and d=0. In the d=1 cases with l=127 and l=255, the effect arising from the depolarization field weakens significantly, and the enhancement of TS results from the in-plane biaxial compressive strain. In the d=0 case with l=32, there is no depolarization field and enhancement of TC by the in-plane biaxial compressive strain is effective even in very thin films. We note that √⟨u2z⟩ and √⟨u2x⟩ are distinct even at high temperatures (see Fig. 4e), indicating that the symmetry of the paraelectric phase is broken by the presence of the epitaxial constraint and the electrodes, as well as correlations between local dipoles and their images.
For films with a dead layer (d=1), the striped domain structures appear in the cooling-down simulations at low temperatures for all values of thicknesses l explored here (see Fig. 5(b) and (c) for the case of l=15 with d=1, and Fig. 6 for various l).
Figure 6: Horizontal slices of snapshots at 100 K in cooling-down simulations of ferroelectric thin-film capacitors with single dead layer (d=1) of various thickness l=7, 15, 31, 63, 127, and 255. The +z-polarized and −z-polarized sites are denoted by □ and ■, respectively.
As shown in Table 1, the wavevector k of the striped domain, at which ˜uz(k) has the largest amplitude |˜uz(k)|, exhibits an interesting dependence on thickness l. We have determined k for two supercell sizes, 32×32×2(l+d) and 40×40×2(l+d), to identify supercell-size effects. It can be seen that, except for the data for l=255, k tends to be along the in-plane {110} direction, consistent with earlier reports. Tinte and Stachiotti (2001); Lai et al. (2007a) The simulated striped domain structure for l=255, which is parallel to the {100} direction, is likely to be an artifact of the finite supercell-size: Lx×Ly=32×32 or even 40×40 are too small to allow for the formation of a sufficiently thick {110} striped domain.
32×32×2(l+d)
7 { 4/32 3/32 0 } { 5/40 5/40 0 }
15 { 3/32 3/32 0 } { 4/40 3/40 0 }
127 { 1/32 1/32 0 } { 1/40 1/40 0 }
Table 1: Dependence of the wavevector k/2π of the striped domain structure on thickness l in the thin-film BaTiO3 capacitor with a dead layer (d=1).
The wavelength λ=2π/|k| of dominant periodicity of the domain pattern is shown as a function of thickness l in Fig. 7, where it is evident that the thinner films have smaller λ to avoid the stronger depolarization field, Eq. (26). The fitting shown in Fig. 7 suggests a square-root dependence Kittel (1946) on l (the result for l=255 is not included in the fit). Extensive simulations at larger length scales would probably be required to clarify further the dependence of the domain period of these striped structures on film thickness and dead-layer thickness.
Figure 7: Calculated thickness l dependence of wavelength λ of striped domain structures in thin film BaTiO3 capacitors with a dead layer (d=1). + marks are from 32×32×2(l+d) supercell calculations and × are those of 40×40×2(l+d). Data of l<=127 are fitted with λ=c√l (dotted line). l=255 data are omitted, because of their large supercell-size dependence.
The stark difference in the behavior of ⟨uz⟩ in heating-up and cooling-down simulations hints that the (almost) uniformly polarized state and the ⟨uz⟩=0 striped domain states are frozen and thermal hopping between them may be almost impossible at low temperatures. To understand why both uniformly polarized and striped domain states are stable and thermal hopping between them are difficult, we investigated the effective potential-energy surfaces for striped domain structures of various stripe wavevectors k and various l for thin-film ferroelectric capacitors with and without the dead layer (see Fig. 8(a)-(e)).
Figure 8: Effective potential surfaces of BaTiO3 thin-film capacitors with short-circuited electrodes: (a)-(e), under 1% in-plane biaxial compressive strain arising from epitaxial constraints; (f)-(j), without epitaxial constraints (i.e., for "free" films). The thicknesses of ferroelectric films and dead layers are indicated in each panel with l and d respectively. Total energies as functions of uz are compared among striped domain structures with wavevectors k parallel to (110). k=(000) corresponds to the uniformly polarized structure. The zero of the energy scale is placed at the total energy of the non-polarized uz=0 structure. A negative pressure p=−5 GPa is applied to correct the underestimation in TC.
Omitting surface relaxations in this analysis may be reasonable because the surface relaxations are confined to the surface region of the ferroelectric thin films as shown in Fig. 5(c). It can be seen that thinner ferroelectric film have a shorter stripe wavelength λ=2π/|k| in their ground states. As the thickness l is increased to l≈127, the ground state changes from the striped domain structure to the out-of-plane uniformly-polarized ferroelectric structure (k=(000)). However, on the time scale of our simulations (≈1 ns), even at l≈255 there is no hopping from the striped domain metastable state to the uniformly polarized ground state (Fig. 4(d)). It can also be seen in Fig. 8(a)-(e) that the magnitude of uz which gives the minimum-energy ground state becomes larger, and the minimum energy gets deeper, as l increases, in good correspondence with the thickness dependence of TC. The trend of k with l also shows good agreement with the simulated values shown in Table 1. The simulated stability of the out-of-plane uniformly-polarized states against the energetically lower striped-domain states in thinner (l<127) films at low temperature seems to give support to the recent idea of elastic stabilization of a homogeneously polarized state in strained ultrathin films. Pertsev and Kohlstedt (2007) As shown in Fig. 9(a), the polarization switching in the epitaxially constrained film may be suppressed by the presence of a potential barrier that prevents hopping between the uniformly-polarized and striped-domain states.
Figure 9: Schematic comparison between the epitaxially constrained film and the "free" film. In the epitaxially constrained film, switching may have to climb over a potential barrier, but, in the "free" film, dipoles can be easily rotated and switching can go around a valley of the potential.
For l≤127 with d=1, it is expected that a uniformly polarized film would evolve into a striped domain state, or vice versa, over a sufficiently long time at T<TS. However, the time scale of the evolution might be very much longer than the present simulation time scale (∼1 ns). It might also be expected that, in the cooling-down simulations of films with l≤127 and d=1, the uniformly polarized state is obtained at T<TS. Instead, however, we find that stripes appear. A close inspection of the simulations shows that the stripes form slightly above TS, initially in a somewhat disordered fashion, presumably because such a structure provides a good compromise between energetic and entropic considerations. The stripes then get frozen into place, and become better ordered, as the temperature is reduced below T<TS. Conversely, in the case of d=0 (Fig. 4(e), depolarization field Ed=0), the striped domain stricture does not appear during the heating-up and cooling-down simulations. This may be because, when Ed=0, there is no reason or chance to form a striped domain structure even just above TC. At TC, direct phase transition form paraelectric phase to uniformly polarized ferroelectric phase occurs. Then, below TC, the system tends to be in its ground state, the uniformly polarized ferroelectric structure.
iii.3 Hysteresis loops
A measurement of polarization typically involves use of a triangle-wave electric field for recording the ferroelectric hysteresis loops (inset of Fig. 10). The hysteresis loops and coercive fields Ec depend on the amplitude E0 and frequency f of the applied fields. We simulate hysteresis here using triangle-wave with steps (width Δtnsteps and height ΔE) as sketched schematically in Fig. 10. Thus, the frequency of the applied field in our simulations is f=ΔE/4ΔtnstepsE0.
Figure 10: Schematic illustrations of triangle-wave electric field used to measure ferroelectric hysteresis loops experimentally (inset) and in the present simulations.
We used supercell sizes of Lx×Ly×Lz=16×16×2(l+d) in simulations of hysteresis loops for ferroelectric thin-film capacitors with 1% in-plane biaxial compressive strain and without constraints of strain (namely, the "free" film) (see Fig. 11).
Figure 11: Calculated hysteresis loops for capacitors with (a) epitaxially constrained films, and (b) "free" films of various thickness l and with dead layer d. Supercell sizes were 16×16×2(l+d). Δt=2 fs and nsteps= 50,000. For epitaxially constrained films, E0= 4,000 kV/cm and ΔE= 100 kV/cm are employed. For "free" films, E0= 400 kV/cm and ΔE= 10 kV/cm are employed.
The temperature is maintained at 100 K through the simulations. For both the epitaxially constrained and "free" films, our simulations confirm that the imperfect screening of the electrodes decreases the coercive field as the film thicknesses decreases, as described phenomenologically in Ref. [ Dawber et al., 2003 ]. There is a large (order-of-magnitude) difference in the coercive field Ec between the epitaxially constrained film and the "free" film. This may be because the compressive strain arising from epitaxial constraints prevents the polarization switching, while the inclusion of inhomogeneous strain (i.e., acoustic displacements) eases the switching, as depicted in Fig. 9. The potential barriers themselves are lower in the "free" films than in the epitaxially constrained films (see Fig. 8). We note that hysteresis loops for "free" film capacitors with l=63 and l=127 are very similar to the experimentally observed hysteresis loops of a ferroelectric capacitor with damaged electrodes that have "steps" and "plateaus" during polarization switchings. Scott (2000) This is because, in the "free" film capacitors with imperfect electrodes (d=1), the configuration with out-of-plane polarization is no longer the ground state. In fact, the ground state has a nonzero in-plane polarization. Thus, the dipoles Z∗u(R) have large in-plane components Z∗ux(R) and Z∗uy(R) in the hysteresis-loop simulations (and experiments), as evident in the snapshot shown in Fig. 12.
Figure 12: Vertical cross section of a simulated ferroelectric "free" film capacitor with a single dead layer; 16×16×(l=63, d=1). The snapshot was taken at the point marked "x" in Fig. 11(b). The projection of the dipole moments onto the xz-plane are indicated with arrows.
Unfortunately, attempts to fit our results to the usually-assumed Kay-Dunn scaling of the coercive field Ec with film thickness l of thicker films Kay and Dunn (1962) were unsuccessful, as were attempts to emulate the relatively weak dependence of Ec on l for epitaxially grown high-quality ultrathin films. Kim et al. (2006); Jo et al. (2006a); Petraru et al. (2007) The experimentally observed values of coercive fields Ec for ultrathin BaTiO3 capacitors range from 200 to 500 kV/cm, Kim et al. (2006); Jo et al. (2006a); Petraru et al. (2007) while simulations of epitaxially constrained films largely overestimate Ec, and those of "free" films slightly underestimate Ec. This may be because the switching in real thin-film capacitors is a large-scale (> 100 nm) phenomenon involving defect-mediated nucleation mainly at ferroelectrics-electrodes interfaces, Kay and Dunn (1962); Janovec (1958); Chandra et al. (2004); Kim et al. (2005); Tagantsev and Gerra (2006); Jo et al. (2006b) as well as the possibility that the strain conditions may be intermediate between the cases of epitaxially constrained and "free" films. Such intermediate strain conditions may be achieved and will be simulated with MD in the future by introducing a mechanical boundary condition such as presented in Ref. [ Pertsev and Kohlstedt, 2007 ]. In contrast to our case of ultrathin BaTiO3 capacitors, it is well known that for ultrathin PbZrxT1−xO3 (PZT) capacitors the coercive fields Ec increase with decreasing film thickness l, and there is an argument whether this strong increase of Ec is coming from compressive substrate-induced lattice strain Pertsev et al. (2003) or not. Lee et al. (2007) Constructing a first-principles Hamiltonian for PZT and simulations with this MD method will help us to understand this difference between BaTiO3 and PZT.
Iv Summary
We have developed a robust and highly efficient molecular-dynamics scheme, based on a first-principles effective Hamiltonian formulation, for simulating the behavior of the polarization in perovskite-type ferroelectrics. We have applied this approach to study BaTiO3 ferroelectric thin-film capacitors, with special attention to the dependence on film thickness and choice of electric boundary conditions. We find that striped domain structures tend to form on cooling-down simulations when a ferroelectric dead layer is present near the electrodes, and we study the dependence of the domain period on the conditions of formation. We also study the hysteresis loops for capacitor structures, both with and without such dead layers, and we find dramatic differences in the hysteretic behavior for the cases of elastically constrained or "free" films. Our MD simulator feram will be a powerful tool for further investigations of the physical properties of ferroelectric nanostructures that are relevant for a variety of potential device applications.
Computational resources were provided by the Center for Computational Materials Science, Institute for Materials Research (CCMS-IMR), Tohoku University. We thank the staff at CCMS-IMR for their constant effort. This research was done when T.N. stayed at JNCASR and Rutgers University under the support from JNCASR, Rutgers University, the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, and the Japan Society for the Promotion of Science (JSPS). D.V. acknowledges support of ONR Grant N00014-05-1-0054.
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Ana Kuzmanić
Associate Professor, Theatre
Northwestern School of Communication
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Ana Kuzmanic is Yugoslav born costume designer for theatre and opera. Her theatrical career started while studying costume and fashion design at the Academy of Fine arts in Belgrade. Since 2003 Ana's design work has been seen on Broadway, off Broadway, in the UK and Australia. Nationally Ana designed costumes for the Goodman Theatre, The Guthrie Theater, McCarter Theatre Center, Washington Shakespeare Theatre Company, Berkeley Repertory Theatre, Trinity Repertory Company, Steppenwolf Theatre, Lookingglass Theatre, the Geffen Playhouse, Oregon Shakespeare Festival among many others. Ana's work has been honored with Drama Desk, Helen Hayes, Henry Hewes and Joseph Jefferson nominations and awards. Her designs for the opera include Don Giovanni at the Lyric Opera of Chicago, directed by her by her long-time collaborator Tony Award winning director Robert Falls and world premiere of Eurydice a new opera composed by Matthew Aucoin, with the libretto by Sarah Ruhl and the direction by Tony Award winning director Mary Zimmerman with whom Ana collaborated on several pieces including Steadfast Tin Soldier and Treasure Island. Ana has designed for her fashion label from 1993 to 2001. She is currently an Associate Professor of costume design at Northwestern University in Evanston, USA.