Illustrating Sampling Distribution of a Statistic: Minitab Revisited

ERIC Educational Resources Information Center

Johnson, H. Dean; Evans, Marc A.

2008-01-01

Understanding the concept of the sampling distribution of a statistic is essential for the understanding of inferential procedures. Unfortunately, this topic proves to be a stumbling block for students in introductory statistics classes. In efforts to aid students in their understanding of this concept, alternatives to a lecture-based mode of…

Unlearned Lessons: Six Stumbling Blocks to Our Schools' Success

ERIC Educational Resources Information Center

Popham, W. James

2009-01-01

"Why is it," writes noted assessment expert W. James Popham, "that today's educators seem almost compelled to replicate their predecessors' blunders?" Looking back over a career of more than fifty years in education, Popham identifies six key "unlearned lessons" in education and reflects on their impact on schools, teachers, and students. In an…

Paper Plate Fractions: The Counting Connection

ERIC Educational Resources Information Center

McCoy, Ann; Barnett, Joann; Stine, Tammy

2016-01-01

Without a doubt, fractions prove to be a stumbling block for many children. Researchers have suggested a variety of explanations for why this is the case. The introduction of symbolization and operations before the development of conceptual understanding of fractions, a lack of understanding of the role of the numerator and denominator, and an…

Providing Quality Laboratories to Long-Distance Educational Programs.

ERIC Educational Resources Information Center

Gammon, Tammy; Sutton, John

2003-01-01

North Carolina State University (UNC) has been on the forefront of long-distance education by offering a Bachelor of Science in Engineering with a Mechatronics Concentration at its remote campus located at UNC Asheville. The program demonstrates that long-distance laboratories are feasible and should not be a stumbling block to offering…

Young Adults on the Autism Spectrum at College: Successes and Stumbling Blocks

ERIC Educational Resources Information Center

Anderson, Connie; Butt, Catherine

2017-01-01

There is limited information on outcomes for young adults with autism spectrum disorder (ASD), including achievement at college. Qualitative interviews were conducted with 18 families reporting a degree-seeking college experience for their young adult with ASD. Interview transcripts were analyzed using a grounded theory approach. Four themes…

Dropout Prevention in Appalachia: Lessons for the Nation.

ERIC Educational Resources Information Center

Campbell Communications, Inc., Bethesda, MD.

The Appalachian Regional Commission (ARC), in its efforts to improve the economy and quality of life in the Appalachian Region, has identified high school dropouts as a major stumbling block to the area's economic growth. Findings of ARC-sponsored research on dropouts include the following: (1) high school dropouts are a serious problem in…

Public Elementary and Secondary Education in the '80s.

ERIC Educational Resources Information Center

Broudy, H. S.

Privatism, vouchers, too many pressure groups, and a deemphasis of citizenship present the worst stumbling blocks to education. A five-point curriculum model includes: (1) the symbolics of information--the skills of language and computation; (2) the key concepts of a selected set of the physical sciences and mathematics; (3) developmental studies…

Number Sense in the Transition from Natural to Rational Numbers

ERIC Educational Resources Information Center

Van Hoof, Jo; Verschaffel, Lieven; Van Dooren, Wim

2017-01-01

Background: Rational numbers are of critical importance both in mathematics and in other fields of science. However, they form a stumbling block for learners. One widely known source of the difficulty learners have with rational numbers is the natural number bias, that is the tendency to (inappropriately) apply natural number properties in…

Presenting Lexical Bundles for Explicit Noticing with Schematic Linguistic Representation

ERIC Educational Resources Information Center

Thomson, Haidee Elizabeth

2016-01-01

Lexical bundles are essential for fluency, but their incompleteness is a stumbling block for learners. In this study, two presentation methods to increase awareness of lexical bundles through explicit noticing are explored and compared with incidental exposure. The three conditions in this study were as follows: noticing with schematic linguistic…

Stemming, Jointing, and Eradicating Legitimate Learning Quagmires.

ERIC Educational Resources Information Center

Horton, Thelma White

This position paper on teaching children to read explains with several examples exactly what "quagmires" are and how they hamper children as they learn the elements of reading basics. The paper takes a multidisciplinary approach to attacking stumbling blocks to learning most often experienced by child learners. To explain the concept of quagmire,…

Identifying and Overcoming Threshold Concepts and Conceptions: Introducing a Conception-Focused Curriculum to Course Design

ERIC Educational Resources Information Center

Burch, Gerald F.; Burch, Jana J.; Bradley, Thomas P.; Heller, Nathan A.

2015-01-01

Educators have been challenged to identify threshold concepts and develop transformed students. This stands in stark contrast to many curriculum design and delivery models that currently view students as repositories of knowledge. In this article, we argue that educators can reach both goals, identify stumbling blocks and transforming students,…

Liberal Practices in a Global World: Stumbling Blocks for Democratic Citizenship Education

ERIC Educational Resources Information Center

Chaput, Catherine; O'Sullivan, Michael

2013-01-01

Reflecting on our efforts to provide Canadian university students with a transformative learning experience in Cuba, we were surprised to find that dominant forms of liberal thinking were more difficult to challenge than was anticipated. This paper explores this phenomenon and offers deliberation as a means toward lessening the stronghold of such…

Learning Fractions by Splitting: Using Learning Analytics to Illuminate the Development of Mathematical Understanding

ERIC Educational Resources Information Center

Martin, Taylor; Petrick Smith, Carmen; Forsgren, Nicole; Aghababyan, Ani; Janisiewicz, Philip; Baker, Stephanie

2015-01-01

The struggle with fraction learning in kindergarten through Grade 12 in the United States is a persistent problem and one of the major stumbling blocks to succeeding in higher mathematics. Research into this problem has identified several areas where students commonly struggle with fractions. While there are many theories of fraction learning,…

Fall Prevention Hits Stumbling Blocks.

PubMed

Huff, Charlotte

2018-03-01

Implementation of efforts to screen older people for fall risk-and to intervene before falls occur-have been scattershot at best. Ongoing studies of fall prevention called STRIDE (Strategies to Reduce Injuries and Develop Confidence in Elders) might change that. The studies look at whether clinicians can implement a fall-prevention program across rural, urban, and suburban treatment settings.

History Education and Reconciliation: Comparative Perspectives on East Asia

ERIC Educational Resources Information Center

Han, Un-suk, Ed.; Kondo, Takahiro, Ed.; Yang, Biao, Ed.; Pingel, Falk, Ed.

2012-01-01

The legacy of crimes committed during the Second World War in East Asia is still a stumbling block for reconciliation and trustful cultural relations between South Korea, China and Japan. The presentation of this issue in history school books is in the focus of a heated public and academic debate. This book written by historians and pedagogues…

Sowing the Seeds of Algebraic Generalization: Designing Epistemic Affordances for an Intelligent Microworld

ERIC Educational Resources Information Center

Mavrikis, M.; Noss, R.; Hoyles, C.; Geraniou, E.

2013-01-01

This paper describes the design of a mathematical microworld to tackle the persistent difficulties that secondary school students have with the idea of algebraic generalization, which is a key stumbling block in secondary-school mathematics classrooms. Our focus is to characterize algebraic ways of thinking and to design both affordances of the…

Turning stumbling blocks into stepping stones in the analysis of cumulative impacts

Treesearch

Leslie M. Reid

2004-01-01

Federal and state legislation, such as the National Environmental Policy Act and the California Environmental Quality Act, require that responsible agency staff consider the cumulative impacts of proposed activities before permits are issued for certain kinds of public or private projects. The Council on Environmental Quality (CEQ 1997) defined a cumulative impact as...

Scientists Are from Mars, Laypeople Are from Venus: An Evidence-Based Approach to Consensus Messaging

NASA Astrophysics Data System (ADS)

Cook, J.; Jacobs, P.; Nuccitelli, D.

2014-12-01

Laypeople use expert opinion as a mental shortcut to form views on complex scientific issues. This heuristic is particularly relevant in the case of climate change, where perception of consensus is one of the main predictors of public support for climate action. A low public perception of consensus (around 60% compared to the actual 97% consensus) is a significant stumbling block to meaningful climate action, underscoring the importance of closing the "consensus gap". However, some scientists question the efficacy or appropriateness of emphasizing consensus in climate communication. I'll summarize the social science research examining the importance and effectiveness of consensus messaging. I'll also present several case studies of consensus messaging employed by the team of communicators at the Skeptical Science website.

Discriminant Validity of Self-Reported Emotional Intelligence: A Multitrait-Multisource Study

ERIC Educational Resources Information Center

Joseph, Dana L.; Newman, Daniel A.

2010-01-01

A major stumbling block for emotional intelligence (EI) research has been the lack of adequate evidence for discriminant validity. In a sample of 280 dyads, self- and peer-reports of EI and Big Five personality traits were used to confirm an a priori four-factor model for the Wong and Law Emotional Intelligence Scale (WLEIS) and a five-factor…

The Teaching and Learning of Spelling in the Spanish Heritage Language Classroom: Mastering Written Accent Marks

ERIC Educational Resources Information Center

Beaudrie, Sara M.

2017-01-01

Spanish spelling, especially the use of written accent marks, is a major stumbling block for Spanish heritage language (SHL) learners (Carreira 2002). In fact, Mikulski (2006) found that most SHL learners ranked bettering their spelling and grammar as a very important learning goal. Despite its importance in literacy development and its perceived…

Making Sense of Iconic Symbols: A Study of Preschool Children Conducting a Refuse-Sorting Task

ERIC Educational Resources Information Center

Ljung-Djärf, Agneta; Åberg-Bengtsson, Lisbeth; Ottosson, Torgny; Beach, Dennis

2015-01-01

This article is part of a larger project focusing upon explanatory illustrations that children encounter in pre- and primary school education. The research questions concerned (a) how preschool children make sense of iconic symbols when placing items of refuse on illustrations of refuse bins in a sorting task and (b) what stumbling blocks they…

Removing Legal Barriers around Work-Based Learning. Connecting the Classroom to Careers: The State's Role in Work-Based Learning

ERIC Educational Resources Information Center

Advance CTE: State Leaders Connecting Learning to Work, 2016

2016-01-01

This report, the second installment in Advance CTE's "Connecting the Classroom to Careers," series, explores an issue that is often a stumbling block for K-12 work-based learning--ensuring these experiences are safe and legal for students. This report features New Jersey, Kentucky and California and their approaches to dismantling…

Airman Scholar Journal. Volume 19, Spring 2013

DTIC Science & Technology

2013-01-01

of technological prowess and a symbol of ideological victory over communism . The Apollo program, which Stephen Johnson has called the United States...CO,80840 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11 ...Space Deterrence in a Labrynthine World Zachary Crippen and Andrew Hilton Topical Focus: Proliferation and Deterrence 11 Racism: A Stumbling Block to

Is Everyone Really Equal? An Introduction to Key Concepts in Social Justice Education. Second Edition. Multicultural Education Series

ERIC Educational Resources Information Center

Sensoy, Ozlem; DiAngelo, Robin

2017-01-01

This is the new edition of the award-winning guide to social justice education. Based on the authors' extensive experience in a range of settings in the United States and Canada, the book addresses the most common stumbling blocks to understanding social justice. This comprehensive resource includes new features such as a chapter on…

Faculty Science Positions Continue to Elude Women of Color: Oklahoma Professor's Study Finds Hiring, Tenure Remain Stumbling Blocks

ERIC Educational Resources Information Center

Hamilton, Kendra

2004-01-01

Women and underrepresented minorities are receiving the doctorate in record numbers these days. For example, women got 45 percent and minorities 19 percent of the 39,955 doctoral degrees awarded in 2000, and both figures were all-time highs. So it comes as something of a surprise to learn that senior academic women in science and engineering are…

Toward a roadmap for interdisciplinary academic career success.

PubMed

McBride, Angela Barron

2010-01-01

The 21st century is a period of increased focus on interdisciplinary collaboration. To facilitate movement in the direction of interdisciplinary research, this article discusses some generic stumbling blocks, unique problems, and advantages that nurses experience, plus the rewards and hallmarks of well-functioning interdisciplinary research teams. The article ends with an overview of how interdisciplinary development can and should be part of each stage of academic career success.

Don't Let Micropayments Penalize You--Experience from the City University of Hong Kong

ERIC Educational Resources Information Center

Ching, Steve H.; Tai, Alice; Pong, Joanna; Cheng, Michael

2009-01-01

Self-service is the trend of today's libraries. The Run Run Shaw Library at the City University of Hong Kong therefore is transforming itself in the same direction and offers to its users what it calls the Easy-service. However, the need to handle cash-based micropayments at the service counter is a stumbling block. There is an urgent need for the…

Integrating Identity Management With Federated Healthcare Data Models

NASA Astrophysics Data System (ADS)

Hu, Jun; Peyton, Liam

In order to manage performance and provide integrated services, health care data needs to be linked and aggregated across data sources from different organizations. The Internet and secure B2B networks offer the possibility of providing near real-time integration. However, there are three major stumbling blocks. One is to standardize and agree upon a common data model across organizations. The second is to match identities between different locations in order to link and aggregate records. The third is to protect identity and ensure compliance with privacy laws. In this paper, we analyze three main approaches to the problem and use a healthcare scenario to illustrate how each one addresses different aspects of the problem while failing to address others. We then present a systematic framework in which the different approaches can be flexibly combined for a more comprehensive approach to integrate identity management with federated healthcare data models.

La Exploracion Del Contexto Social y Sus Efectos en el Programa de Espanol en Mexico Rural. (Exploring the Social Context Affecting a Pre-School Spanish Program in Rural Mexico).

ERIC Educational Resources Information Center

Finegold, Lynda

A major stumbling block for the implementation of Mexico's Global Development Plan has been the country's large rural population of Indians. One government strategy to integrate this sector into the mainstream of society has been to teach Spanish, the official language, as a second language, while at the same time fostering ethnic pride. The…

Can you prove it? There is no magic bullet for reporting capabilities to meet meaningful use guidelines.

PubMed

Lawrence, Daphne

2010-04-01

In order to qualify for meaningful use in 2011, hospitals will only need to use attestation. Hospitals will have to submit data to CMS electronically in 2012. Not all the data elements needed to prove meaningful use are routinely captured. Standardization is a stumbling block to reporting. For medium to large hospitals using a vendor to set up the reporting is an option.

[Success Factors and Stumbling Blocks in the Cooperation with Child and Adolescent Psychiatry/Psychotherapy from the Perspective of Social Pedagogues].

PubMed

Müller-Luzi, Seraina; Schmid, Marc

2017-10-01

Success Factors and Stumbling Blocks in the Cooperation with Child and Adolescent Psychiatry/Psychotherapy from the Perspective of Social Pedagogues In numerous current studies, experts describe a need for improved cooperation between employees of youth welfare and child and adolescent psychiatry/-psychotherapy. The present study investigates how social pedagogues working in youth welfare institutions perceive psychiatrists or psychologists working in child and adolescent psychiatry. Benefits and difficulties of the cooperation are described and potential areas of improvement as perceived by youth welfare employees are identified. The study presents quantitative and qualitative data and pursues a mixed-method approach. The qualitative evaluation is based on the content structuring qualitative content analysis according to Kuckartz (2012) and is complemented by descriptive data. The results are based on the responses of 221 social pedagogues in Switzerland. While 97.7 % of respondents perceive interdisciplinary collaborations for children with high psychological stress as ideal, they also mention various barriers that hinder effective and efficient cooperation. Many social pedagogues wish for the field of child and adolescent psychiatry to show a greater interest in their job profile, as well as more appreciation for the demanding work that they perform. Clarification of roles and responsibilities, a better flow of information and a direct person of contact are also deemed important aspects to improve upon. The study suggests practical approaches for a more effective cooperation.

Arms Control Verification Is No Longer a Stumbling Block to True Disarmament

DTIC Science & Technology

1992-05-01

that they had had sirce 1945.17 The Atomoic Energy Cormission failed to reach an agreeriment due to the deadlock between the two plans. The Soviet...the Soviets exploding their first nuclear device on September 2", 149 ’ 13 The talks or general and complete disarmament had failed. The failure to...and by the general state of international arid do,mestic toolitics at the time. 7 Adequate verificat ion involves the acceptance of a. degree of

More and more power plant flyash is being recycled

DOE Office of Scientific and Technical Information (OSTI.GOV)

Golden, D.; Sauber, R.

A number of viable options have been demonstrated for recycling flyash, one of America's fastest-growing waste products. Application opportunities range from structural fills to pavement bases, concrete, stabilizing backfills, and a metal-castings alloy. But two stumbling blocks still face utilities and marketers of flyash. They are: (1) Convincing potential end users that flyash is a beneficial raw material and not an inferior waste product. (2) Persuading regulatory agencies to draft legislation, that promote, if not mandate, its use.

South Asia and US Interests: Peripheral, But Impossible to Ignore* (*1 Billion+ People Can Quickly Get Your Attention)

DTIC Science & Technology

1996-01-01

Hinduism was born in India, and Its precepts strongly affect Indian attrtudes toward life and society The Mughal conquest in the 16th century, lasting...significant stumbling block to Indian and Pakistani cooperation on a wide range of Issues, and precludes effective regional cooperation The acquisition...comonsec of Bangladesn Ehutan lncra the Maldives, Nepal , >a<stan and Sn Lanqa has been a crossroads of crviirzatron and history for centunes The cradle o

Poisoning by Indigofera lespedezioides in horses

USDA-ARS?s Scientific Manuscript database

Poisoning by Indigofera lespedezioides is reported in horses in the state of Roraima, northern Brazil. The main clinical signs are anorexia, sleepiness, unsteady gait, severe ataxia, weakness, stumbling, and progressive weight loss. To induce the disease experimentally, a 7-year-old horse was introd...

A study of Iranian immigrants’ experiences of accessing Canadian health care services: a grounded theory

PubMed Central

2012-01-01

Background Immigration is not a new phenomenon but, rather, has deep roots in human history. Documents from every era detail individuals who left their homelands and struggled to reestablish their lives in other countries. The aim of this study was to explore and understand the experience of Iranian immigrants who accessed Canadian health care services. Research with immigrants is useful for learning about strategies that newcomers develop to access health care services. Methods The research question guiding this study was, “What are the processes by which Iranian immigrants learn to access health care services in Canada?” To answer the question, a constructivist grounded theory approach was applied. Initially, unstructured interviews were conducted with 17 participants (11 women and six men) who were adults (at least 18 years old) and had immigrated to Canada within the past 15 years. Eight participants took part in a second interview, and four participants took part in a third interview. Results Using a constructivist grounded theory approach, “tackling the stumbling blocks of access” emerged as the core category. The basic social process (BSP), becoming self-sufficient, was a transitional process and had five stages: becoming a stranger; feeling helpless; navigating/seeking information; employing strategies; and becoming integrated and self-sufficient. We found that “tackling the stumbling blocks of access” was the main struggle throughout this journey. Some of the immigrants were able to overcome these challenges and became proficient in accessing health care services, but others were unable to make the necessary changes and thus stayed in earlier stages/phases of transition, and sometimes returned to their country of origin. Conclusion During the course of this journey a substantive grounded theory was developed that revealed the challenges and issues confronted by this particular group of immigrants. This process explains why some Iranian immigrants are able to access Canadian health care effectively while others cannot. Many elements, including language proficiency, cultural differences, education, previous experiences, financial status, age, knowledge of the host country’s health care services, and insider and outsider resources work synergistically in helping immigrants to access health care services effectively and appropriately. PMID:23021015

Empowerment in the field of health promotion: recognizing challenges in working toward equity.

PubMed

Berry, Nicole S; Murphy, Jill; Coser, Larissa

2014-12-01

Over the last 25 years, the language of empowerment has been woven into the guiding missions and descriptions of institutions, funding and projects globally. Although theoretical understandings of empowerment within the domain of health promotion remain contentious, we have little idea of how a shift toward an empowerment agenda has affected the daily work of those in the field of health promotion. A systematic examination of the implementation of the empowerment agenda is important as it can help us understand how redistributive agendas are received within the multiple institutional contexts in which health promotion work is carried out. The goal of this study, therefore, was to try to understand the empowerment agenda within the context of everyday health promotion. We conducted semi-structured interviews with health promoters from a variety of geographical regions, institutional backgrounds, and job capacities. Essentially we found that empowerment remains conceptually dear to health promoters' understanding of their work, yet at the same time, mainstreaming empowerment is at odds with central trends and initiatives that govern this work. We argue that many of the stumbling blocks that have hindered this specific agenda are actually central stumbling blocks for the wider field of health promotion. We examine some of the barriers to implementing transformational change. Overcoming the primary limitations uncovered in this exploration of empowerment is actually crucial to progressive work in health promotion in general, particularly work that would seek to lessen inequities. © The Author(s) 2014.

Regaining momentum for international climate policy beyond Copenhagen

PubMed Central

2010-01-01

The 'Copenhagen Accord' fails to deliver the political framework for a fair, ambitious and legally-binding international climate agreement beyond 2012. The current climate policy regime dynamics are insufficient to reflect the realities of topical complexity, actor coalitions, as well as financial, legal and institutional challenges in the light of extreme time constraints to avoid 'dangerous' climate change of more than 2°C. In this paper we analyze these stumbling blocks for international climate policy and discuss alternatives in order to regain momentum for future negotiations. PMID:20525341

High Added Value - but Many Stumbling Blocks along the Way NTN Biotech Identifies where the Shoe Pinches.

PubMed

Heinzelmann, Elsbeth

2016-01-01

The year 1958, when DNA was first made in a test tube, marked the birth of modern biotechnology. DNA has now developed into an important technology that makes a key contribution in various sectors such as agriculture, environment and cleansing, and it has triggered a veritable boom in medicine. Today, biologics account for more than 60% of newly approved drugs. They are efficient, save time and money and have few or minimal side effects, fuelling the appetite of big pharma to take over biotech companies. Where will the journey lead?

Ethics and the psychiatry journal editor: responsibilities and dilemmas.

PubMed

Greenberg, David; D Strous, Rael

2014-01-01

An array of potential ethical stumbling blocks awaits the editors of scientific journals. There are issues of particular relevance to mental health journals, and others unique to local journals with a relatively small circulation and low impact factor. The blind review system, conflict of interests, redundant publication, fraud and plagiarism, guest and ghost authorship and ghost writing, advertising, language and stigma, patient consent, and "rigging" the Impact Factor are all issues of importance. It is critical that editors are aware and informed of these important issues, and have an accessible forum for evaluating problems as they arise.

Cuba Country Analysis Brief

EIA Publications

2016-01-01

Cuba imports the majority of their energy needs, but offshore oil and gas potential could help mitigate their reliance imports. Cuba has entered into many agreements with various countries to help with exploration and drilling efforts. As a result of the ongoing U.S. trade embargo against Cuba, U.S. companies are unable to own any Cuban oil assets. However, U.S. oil companies are allowed to participate in drilling as well as sending technology and supplies with an executive license. While there is interest in Cuban offshore assets, the combination of low oil prices and technically challenging fields could be stumbling blocks for foreign investment.

List blocking and longer retention intervals reveal an influence of gist processing for lexically ambiguous critical lures

PubMed Central

McNabb, Jaimie; Hutchison, Keith A.

2016-01-01

In two experiments, we examined veridical and false memory for lists of associates from two meanings (e.g., stumble, trip, harvest, pumpkin, etc.) that converged upon a single, lexically ambiguous critical lure (e.g., fall), in order to compare the activation-monitoring and fuzzy-trace false memory accounts. In Experiment 1, we presented study lists that were blocked or alternated by meaning (within subjects), followed by a free recall test completed immediately or after a 2.5-min delay. Correct recall was greater for blocked than for alternated lists. Critical-lure false recall was greater for blocked lists on an immediate test, whereas both list types produced equivalent false recall on a delayed test. In Experiment 2, lists blocked and alternated by meaning were presented via a between-subjects design, in order to eliminate possible list-type carryover effects. Correct recall replicated the result from Experiment 1; however, blocking lists increased false recall on delayed, but not on immediate, tests. Across the experiments, clustering correct recall by meaning increased across the delay selectively for the alternated lists. Our results suggest that thematic (i.e., gist) processes are influential for false recall, especially following a delay, a pattern consistent with fuzzy-trace theory. PMID:26105976

Case study of a floor-cleaning robot

NASA Astrophysics Data System (ADS)

Branch, Allan C.

1998-01-01

Developing the technologies suitable of ra high level robotic application such as cleaning a floor has proved extremely difficult. Developing the robot mobility technology has been a stumbling block and developing and integrating the applications technology to the machine and the mobility technology has also been a difficult stage in this quest, but doing so in a cost effective and realistic manner suitable for the market place and to compete with humans and manually operated machines has been the most difficult of all. This paper describes one of these quests spanning a 14 year period and resulting in what is hoped will be the world's first commercially manufactured household robot vacuum cleaner.

Adequate representation of charge polarization effects leads to a successful treatment of the CF4 + SiCl4 → CCl4 + SiF4 reaction by density functional theory.

PubMed

Li, Ruifang; Zhao, Yan; Truhlar, Donald G

2011-02-28

Adequate polarization functions reduce the error of density functional theory (DFT) for the heat of reaction for CF(4) + SiCl(4) from ∼9-12 kcal mol(-1) to ∼2-4 kcal mol(-1), and using an improved density functional further reduces it to ∼1 kcal mol(-1). This reaction was previously identified as a stumbling block for DFT, but we show that the problem with the previous calculations was not DFT but rather inadequate basis sets to account for intramolecular charge polarization.

Transmission blocking malaria vaccines: Assays and candidates in clinical development.

PubMed

Sauerwein, R W; Bousema, T

2015-12-22

Stimulated by recent advances in malaria control and increased funding, the elimination of malaria is now considered to be an attainable goal for an increasing number of malaria-endemic regions. This has boosted the interest in transmission-reducing interventions including vaccines that target sexual, sporogenic, and/or mosquito-stage antigens to interrupt malaria transmission (SSM-VIMT). SSM-VIMT aim to prevent human malaria infection in vaccinated communities by inhibiting parasite development within the mosquito after a blood meal taken from a gametocyte carrier. Only a handful of target antigens are in clinical development and progress has been slow over the years. Major stumbling blocks include (i) the expression of appropriately folded target proteins and their downstream purification, (ii) insufficient induction of sustained functional blocking antibody titers by candidate vaccines in humans, and (iii) validation of a number of (bio)-assays as correlate for blocking activity in the field. Here we discuss clinical manufacturing and testing of current SSM-VIMT candidates and the latest bio-assay development for clinical evaluation. New testing strategies are discussed that may accelerate the evaluation and application of SSM-VIMT. Copyright © 2015. Published by Elsevier Ltd.

Computing at the speed limit (supercomputers)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernhard, R.

1982-07-01

The author discusses how unheralded efforts in the United States, mainly in universities, have removed major stumbling blocks to building cost-effective superfast computers for scientific and engineering applications within five years. These computers would have sustained speeds of billions of floating-point operations per second (flops), whereas with the fastest machines today the top sustained speed is only 25 million flops, with bursts to 160 megaflops. Cost-effective superfast machines can be built because of advances in very large-scale integration and the special software needed to program the new machines. VLSI greatly reduces the cost per unit of computing power. The developmentmore » of such computers would come at an opportune time. Although the US leads the world in large-scale computer technology, its supremacy is now threatened, not surprisingly, by the Japanese. Publicized reports indicate that the Japanese government is funding a cooperative effort by commercial computer manufacturers to develop superfast computers-about 1000 times faster than modern supercomputers. The US computer industry, by contrast, has balked at attempting to boost computer power so sharply because of the uncertain market for the machines and the failure of similar projects in the past to show significant results.« less

Arresting Evolution.

PubMed

Bull, James J; Barrick, Jeffrey E

2017-12-01

Evolution in the form of selective breeding has long been harnessed as a useful tool by humans. However, rapid evolution can also be a danger to our health and a stumbling block for biotechnology. Unwanted evolution can underlie the emergence of drug and pesticide resistance, cancer, and weeds. It makes live vaccines and engineered cells inherently unreliable and unpredictable, and therefore potentially unsafe. Yet, there are strategies that have been and can possibly be used to stop or slow many types of evolution. We review and classify existing population genetics-inspired methods for arresting evolution. Then, we discuss how genome editing techniques enable a radically new set of approaches to limit evolution. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

How to Write Your First Research Paper

PubMed Central

Kallestinova, Elena D.

2011-01-01

Writing a research manuscript is an intimidating process for many novice writers in the sciences. One of the stumbling blocks is the beginning of the process and creating the first draft. This paper presents guidelines on how to initiate the writing process and draft each section of a research manuscript. The paper discusses seven rules that allow the writer to prepare a well-structured and comprehensive manuscript for a publication submission. In addition, the author lists different strategies for successful revision. Each of those strategies represents a step in the revision process and should help the writer improve the quality of the manuscript. The paper could be considered a brief manual for publication. PMID:21966034

Faster Legionella testing on horizon.

PubMed

Pearson, Susan

2011-08-01

While the "traditional" way to measure Legionella quantitatively in water is based on a complex culture method where results can take up to 14 days, the last few years have seen the availability of very rapid real-time monitoring of the bacterium in water systems, with the development of quantitative polymerase chain reaction (qPCR), a process which gives results "within hours". To date, however, a lack of consensus on how to interpret such results in relation to those from culture has been a stumbling block, although, as Susan Pearson, a freelance journalist and public relations consultant specialising in medicine and the environment, reports, the positive results of a recent multi-centre European study mean this could soon all change.

How to write your first research paper.

PubMed

Kallestinova, Elena D

2011-09-01

Writing a research manuscript is an intimidating process for many novice writers in the sciences. One of the stumbling blocks is the beginning of the process and creating the first draft. This paper presents guidelines on how to initiate the writing process and draft each section of a research manuscript. The paper discusses seven rules that allow the writer to prepare a well-structured and comprehensive manuscript for a publication submission. In addition, the author lists different strategies for successful revision. Each of those strategies represents a step in the revision process and should help the writer improve the quality of the manuscript. The paper could be considered a brief manual for publication. Copyright © 2011.

The efficacy of evolocumab in the management of hyperlipidemia: a systematic review

PubMed Central

AlHajri, Lamia; AlHadhrami, Asma; AlMheiri, Shama; AlMutawa, Yalwah; AlHashimi, Zainab

2017-01-01

Background: Hyperlipidemia or dyslipidemia has been a concern for a long time, with various guidelines emphasizing the importance of managing the lipid profile to prevent cardiac incidences. Although statins have been found to be highly effective, resistance and intolerability to side effects will continue to be a stumbling block for certain patients. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors tackle lipid profile via a novel mechanism and therefore provide an additional effective option for managing lipid profile. The overarching aim of this systematic review was to evaluate the efficacy of evolocumab among various populations with hypercholesterolemia. Methods: A comprehensive search was conducted in ProQuest Health & Medical Complete, Google Scholar, ScienceDirect, and PubMed to identify potential records; then titles, abstracts, and full texts were screened using the inclusion criteria to filter out irrelevant studies. Data extraction and quality assessment were undertaken using standardized tools and the results were narratively synthesized and presented in tables. Results: Eight studies were included in this systematic review after screening 1191 records. All studies demonstrated a statistically significant reduction in low-density lipoprotein cholesterol (LDL-C) values in the groups that received evolocumab compared with the comparator groups (p < 0.05). The decline in LDL-C levels from baseline in the majority of studies ranged from 40% to 80%, whether used alone or in combination with other agents. Also, high-density lipoprotein cholesterol, lipoprotein (a) and apolipoprotein B were improved with the use of evolocumab. Conclusions: This study helped to collate evidence from studies that tested the effectiveness of evolocumab in the management of hyperlipidemia. Evolocumab seems to be highly effective in reducing LDL-C and other lipid parameters. Hence, it provides an excellent alternative for patients with refractory disease or patients who develop intolerable side effects, therefore helping to overcome the stumbling block to achieving optimal lipid management. PMID:28488460

Singularity classification as a design tool for multiblock grids

NASA Technical Reports Server (NTRS)

Jones, Alan K.

1992-01-01

A major stumbling block in interactive design of 3-D multiblock grids is the difficulty of visualizing the design as a whole. One way to make this visualization task easier is to focus, at least in early design stages, on an aspect of the grid which is inherently easy to present graphically, and to conceptualize mentally, namely the nature and location of singularities in the grid. The topological behavior of a multiblock grid design is determined by what happens at its edges and vertices. Only a few of these are in any way exceptional. The exceptional behaviors lie along a singularity graph, which is a 1-D construct embedded in 3-D space. The varieties of singular behavior are limited enough to make useful symbology on a graphics device possible. Furthermore, some forms of block design manipulation that appear appropriate to the early conceptual-modeling phase can be accomplished on this level of abstraction. An overview of a proposed singularity classification scheme and selected examples of corresponding manipulation techniques is presented.

National Vaccine Policy: ethical equity issues.

PubMed

Jayakrishnan, T

2013-01-01

The ministry of health and family welfare published the national vaccination policy in April 2011. The policy document drew severe criticism from several public health experts. A review of the print and web-based literature on the national vaccine policy was done and the issues of ethics and equity involved in introducing new vaccines under the Universal Immunisation Programme (UIP) were studied. The average coverage of the UIP vaccines at the national level is below 50%. Despite this, the policy document did not state any concrete strategy for increasing the coverage. The main stumbling block for evidence-based vaccine policy in India is the lack of reliable epidemiological data, which makes it difficult for the National Technical Advisory Group on Immunisation to offer sound technical advice to the government. No attempts have been made to prioritise diseases or the selection of vaccines. The policy suggests the introduction of the following vaccines in the UIP: Haemophilus influenzae type b, pneumococcal vaccine, rotavirus vaccines and human papillomavirus (HPV). This selection is on the grounds of the vaccines' availability, not on the basis of epidemiological evidence or proven cost-effectiveness. This is a critical review of the current vaccination policy and the move to include the rotavirus and HPV vaccines in the UIP.

Endgame: engaging the tobacco industry in its own elimination

PubMed Central

Ioannidis, John P. A.; Henriksen, Lisa; Prochaska, Judith J.

2014-01-01

A billion deaths from tobacco are expected by 2100. Many policy interventions such as increased taxation, restrictions on advertisement, smoking bans, as well as behavioral interventions, such as pharmacological and psychological treatments for smoking cessation, decrease tobacco use, but they reach their limits. Endgame scenarios focusing on tobacco supply rather than demand are increasingly discussed, but meet with resistance by the industry and even by many tobacco control experts. A main stumbling block that requires more attention is what to do with the tobacco industry in endgame scenarios. This industry has employed notoriously talented experts in law, business, organization, marketing, advertising, strategy, policy, and statistics and has tremendous lobbying power. Performance-based regulatory approaches can pose a legal obligation on manufacturers to decrease – and eventually – eliminate tobacco products according to specified schedules. Penalties and rewards can make such plans both beneficial for public health and attractive to the companies that do the job well. We discuss caveats and reality checks of engaging the tobacco industry to eliminate its current market and change focus. Brainstorming is warranted to entice the industry to abandon tobacco for other profit goals. To get the dialogue started, we propose the wild possibility of hiring former tobacco companies to reduce the costs of healthcare, thereby addressing concurrently two major challenges to public health. PMID:24117211

Poor anchoring limits dyslexics' perceptual, memory, and reading skills.

PubMed

Oganian, Yulia; Ahissar, Merav

2012-07-01

The basic deficits underlying the severe and persistent reading difficulties in dyslexia are still highly debated. One of the major topics of debate is whether these deficits are language specific, or affect both verbal and non-verbal stimuli. Recently, Ahissar and colleagues proposed the "anchoring-deficit hypothesis" (Ahissar, Lubin, Putter-Katz, & Banai, 2006), which suggests that dyslexics have a general difficulty in automatic extraction of stimulus regularities from auditory inputs. This hypothesis explained a broad range of dyslexics' verbal and non-verbal difficulties. However, it was not directly tested in the context of reading and verbal memory, which poses the main stumbling blocks to dyslexics. Here we assessed the abilities of adult dyslexics to efficiently benefit from ("anchor to") regularities embedded in repeated tones, orally presented syllables, and written words. We also compared dyslexics' performance to that of individuals with attention disorder (ADHD), but no reading disability. We found an anchoring effect in all groups: all gained from stimulus repetition. However, in line with the anchoring-deficit hypothesis, controls and ADHD participants showed a significantly larger anchoring effect in all tasks. This study is the first that directly shows that the same domain-general deficit, poor anchoring, characterizes dyslexics' performance in perceptual, working memory and reading tasks. Copyright © 2012 Elsevier Ltd. All rights reserved.

The use of digital games and simulators in veterinary education: an overview with examples.

PubMed

de Bie, M H; Lipman, L J A

2012-01-01

In view of current technological possibilities and the popularity of games, the interest in games for educational purposes is remarkably on the rise. This article outlines the (future) use of (digital) games and simulators in several disciplines, especially in the veterinary curriculum. The different types of game-based learning (GBL)-varying from simple interactive computer board games to more complex virtual simulation strategies-will be discussed as well as the benefits, possibilities, and limitations of the educational use of games. The real breakthrough seems to be a few years away. Technological developments in the future might diminish the limitations and stumbling blocks that currently exist. Consequently, educational games will play a new and increasingly important role in the future veterinary curriculum, providing an attractive and useful way of learning.

Towards Establishing Fiscal Legitimacy Through Settled Fiscal Principles in Global Health Financing.

PubMed

Waris, Attiya; Latif, Laila Abdul

2015-12-01

Scholarship on international health law is currently pushing the boundaries while taking stock of achievements made over the past few decades. However despite the forward thinking approach of scholars working in the field of global health one area remains a stumbling block in the path to achieving the right to health universally: the financing of heath. This paper uses the book Global Health Law by Larry Gostin to reflect and take stock of the fiscal support provided to the right to health from both a global and an African perspective. It then sets out the key fiscal challenges facing global and African health and proposes an innovative solution for consideration: use of the domestic principles of tax to design the global health financing system.

Business continuity 2014: From traditional to integrated Business Continuity Management.

PubMed

Ee, Henry

As global change continues to generate new challenges and potential threats to businesses, traditional business continuity management (BCM) slowly reveals its limitations and weak points to ensuring 'business resiliency' today. Consequently, BCM professionals also face the challenge of re-evaluating traditional concepts and introducing new strategies and industry best practices. This paper points to why traditional BCM is no longer sufficient in terms of enabling businesses to survive in today's high-risk environment. It also looks into some of the misconceptions about BCM and other stumbling blocks to establishing effective BCM today. Most importantly, however, this paper provides tips based on the Business Continuity Institute's (BCI) Good Practices Guideline (GPG) and the latest international BCM standard ISO 22301 on how to overcome the issues and challenges presented.

Supported molten-metal catalysts

DOEpatents

Datta, Ravindra; Singh, Ajeet; Halasz, Istvan; Serban, Manuela

2001-01-01

An entirely new class of catalysts called supported molten-metal catalysts, SMMC, which can replace some of the existing precious metal catalysts used in the production of fuels, commodity chemicals, and fine chemicals, as well as in combating pollution. SMMC are based on supporting ultra-thin films or micro-droplets of the relatively low-melting (<600.degree. C.), inexpensive, and abundant metals and semimetals from groups 1, 12, 13, 14, 15 and 16, of the periodic table, or their alloys and intermetallic compounds, on porous refractory supports, much like supported microcrystallites of the traditional solid metal catalysts. It thus provides orders of magnitude higher surface area than is obtainable in conventional reactors containing molten metals in pool form and also avoids corrosion. These have so far been the chief stumbling blocks in the application of molten metal catalysts.

A Hierarchical Model for Simultaneous Detection and Estimation in Multi-subject fMRI Studies

PubMed Central

Degras, David; Lindquist, Martin A.

2014-01-01

In this paper we introduce a new hierarchical model for the simultaneous detection of brain activation and estimation of the shape of the hemodynamic response in multi-subject fMRI studies. The proposed approach circumvents a major stumbling block in standard multi-subject fMRI data analysis, in that it both allows the shape of the hemodynamic response function to vary across region and subjects, while still providing a straightforward way to estimate population-level activation. An e cient estimation algorithm is presented, as is an inferential framework that not only allows for tests of activation, but also for tests for deviations from some canonical shape. The model is validated through simulations and application to a multi-subject fMRI study of thermal pain. PMID:24793829

Synthesis of cytidine ribonucleotides by stepwise assembly of the heterocycle on a sugar phosphate.

PubMed

Ingar, Abdul-Aziz; Luke, Richard W A; Hayter, Barry R; Sutherland, John D

2003-06-06

Although various syntheses of the nucleic acid bases exist and ribose is a product of the formose reaction, no prebiotically plausible methods for attaching pyrimidine bases to ribose to give nucleosides have been described. Kinetic and thermodynamic factors are thought to mitigate against such condensation reactions in aqueous solution. This inability to produce pyrimidine nucleosides and hence nucleotides is a major stumbling block of the "RNA World" hypothesis and has led to suggestions of alternative nucleic acids as evolutionary precursors to RNA. Here, we show that a process in which the base is assembled in stages on a sugar phosphate can produce cytidine nucleotides. The sequential action of cyanamide and cyanoacetylene on arabinose-3-phosphate produces cytidine-2',3'-cyclophosphate and arabinocytidine-3'-phosphate.

Power harvesting using PZT ceramics embedded in orthopedic implants.

PubMed

Chen, Hong; Liu, Ming; Jia, Chen; Wang, Zihua

2009-09-01

Battery lifetime has been the stumbling block for many power-critical or maintenance-free real-time embedded applications, such as wireless sensors and orthopedic implants. Thus a piezoelectric material that could convert human motion into electrical energy provides a very attractive solution for clinical implants. In this work, we analyze the power generation characteristics of stiff lead zirconate titanate (PZT) ceramics and the equivalent circuit through extensive experiments. Our experimental framework allows us to explore many important design considerations of such a PZT-based power generator. Overall we can achieve a PZT element volume of 0.5 x 0.5 x 1.8 cm, which is considerably smaller than the results reported so far. Finally, we outline the application of our PZT elements in a total knee replacement (TKR) implant.

A manual physical therapy intervention for symptoms of knee osteoarthritis and associated fall risk: A case series of four patients.

PubMed

Allen, Chris; Sheehan, Riley; Deyle, Gail; Wilken, Jason; Gill, Norman

2018-02-26

Patients with knee osteoarthritis (OA) are at an increased risk of falling. Further, the symptoms associated with knee OA are correlated with fall risk. A manual physical therapy (MPT) approach consisting of mobilizing techniques and reinforcing exercise improves the symptoms and functional limitations associated with knee OA. The purpose of this case series is to evaluate an MPT intervention of mobilization techniques and exercise for knee OA on improving symptoms and quantify the secondary benefit of improving stumble recovery. Four patients with symptomatic knee OA and four matched controls completed a fall risk assessment. Following 4 weeks of intervention, patients were reevaluated. Initial Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores indicated notable symptoms and functional limitations in all patients. In addition, all patients displayed elevated fall risk and/or impaired stumble responses. Following 4 weeks of intervention, all patients reported meaningful reductions in all three WOMAC subscales and demonstrated improvements in at least two of the three fall risk measures. We identified potential connections between symptom relief in patients with knee OA, stumble response, and ultimately fall risk. The results suggest that MPT intervention designed to improve the signs and symptoms of knee OA may lead to a secondary benefit of improved gait stability and stumble response.

University of TX Bureau of Economic Geology's Core Research Centers: The Time is Right for Registering Physical Samples and Assigning IGSN's - Workflows, Stumbling Blocks, and Successes.

NASA Astrophysics Data System (ADS)

Averett, A.; DeJarnett, B. B.

2016-12-01

The University Of Texas Bureau Of Economic Geology (BEG) serves as the geological survey for Texas and operates three geological sample repositories that house well over 2 million boxes of geological samples (cores and cuttings) and an abundant amount of geoscience data (geophysical logs, thin sections, geochemical analyses, etc.). Material is accessible and searchable online, and it is publically available to the geological community for research and education. Patrons access information about our collection by using our online core and log database (SQL format). BEG is currently undertaking a large project to: 1) improve the internal accuracy of metadata associated with the collection; 2) enhance the capabilities of the database for both BEG curators and researchers as well as our external patrons; and 3) ensure easy and efficient navigation for patrons through our online portal. As BEG undertakes this project, BEG is in the early stages of planning to export the metadata for its collection into SESAR (System for Earth Sample Registration) and have IGSN's (International GeoSample Numbers) assigned to its samples. Education regarding the value of IGSN's and an external registry (SESAR) has been crucial to receiving management support for the project because the concept and potential benefits of registering samples in a registry outside of the institution were not well-known prior to this project. Potential benefits such as increases in discoverability, repository recognition in publications, and interoperability were presented. The project was well-received by management, and BEG fully supports the effort to register our physical samples with SESAR. Since BEG is only in the initial phase of this project, any stumbling blocks, workflow issues, successes/failures, etc. can only be predicted at this point, but by mid-December, BEG expects to have several concrete issues to present in the session. Currently, our most pressing issue involves establishing the most efficient workflow for exporting of large amounts of metadata in a format that SESAR can easily ingest, and how this can be best accomplished with very few BEG staff assigned to the project.

Chondrocyte Culture in Three Dimensional Alginate Sulfate Hydrogels Promotes Proliferation While Maintaining Expression of Chondrogenic Markers

PubMed Central

Mhanna, Rami; Kashyap, Aditya; Palazzolo, Gemma; Vallmajo-Martin, Queralt; Becher, Jana; Möller, Stephanie; Schnabelrauch, Matthias

2014-01-01

The loss of expression of chondrogenic markers during monolayer expansion remains a stumbling block for cell-based treatment of cartilage lesions. Here, we introduce sulfated alginate hydrogels as a cartilage biomimetic biomaterial that induces cell proliferation while maintaining the chondrogenic phenotype of encapsulated chondrocytes. Hydroxyl groups of alginate were converted to sulfates by incubation with sulfur trioxide–pyridine complex (SO3/pyridine), yielding a sulfated material cross-linkable with calcium chloride. Passage 3 bovine chondrocytes were encapsulated in alginate and alginate sulfate hydrogels for up to 35 days. Cell proliferation was five-fold higher in alginate sulfate compared with alginate (p=0.038). Blocking beta1 integrins in chondrocytes within alginate sulfate hydrogels significantly inhibited proliferation (p=0.002). Sulfated alginate increased the RhoA activity of chondrocytes compared with unmodified alginate, an increase that was blocked by β1 blocking antibodies (p=0.017). Expression and synthesis of type II collagen, type I collagen, and proteoglycan was not significantly affected by the encapsulation material evidenced by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. Alginate sulfate constructs showed an opaque appearance in culture, whereas the unmodified alginate samples remained translucent. In conclusion, alginate sulfate provides a three dimensional microenvironment that promotes both chondrocyte proliferation and maintenance of the chondrogenic phenotype and represents an important advance for chondrocyte-based cartilage repair therapies providing a material in which cell expansion can be done in situ. PMID:24320935

[Speech rhythm disorders due to synchronization induced in coupled inhibitory neurons].

PubMed

Skliarov, O P

2007-01-01

Leaked-integrate-and-fire coupled oscillators (LIFs) were used as a model of electrophysiological activity. The activity of these oscillators determines the speech rhythm, which is governed by the square-law map with inhibition as a controlling parameter. Regular rhythms of convulsive repetitions at early stuttering are changed, however, by a mixture of repetitions and neurotic pauses. This mixture is a "stumbling block" for clinicians. Due to delays, only inhibitory LIFs are capable to create the synchronic activity in-phase or in-anti-phase at medial or at low coupling. This activity has the form of slow oscillations damping to the background level. Splashes of the activity above or below the level lead to neurotic disorders or to convulsive repetitions. Really, increased due to GABA the coupling leads to a reduction of stuttering.

Promising and Reversible Electrolyte with Thermal Switching Behavior for Safer Electrochemical Storage Devices.

PubMed

Shi, Yunhui; Zhang, Qian; Zhang, Yan; Jia, Limin; Xu, Xinhua

2018-02-28

A major stumbling block in large-scale adoption of high-energy-density electrochemical devices has been safety issues. Methods to control thermal runaway are limited by providing a one-time thermal protection. Herein, we developed a simple and reversible thermoresponsive electrolyte system that is efficient to shutdown the current flow according to temperature changes. The thermal management is ascribed to the thermally activated sol-gel transition of methyl cellulose solution, associated with the concentration of ions that can move between isolated chains freely or be restricted by entangled molecular chains. We studied the effect of cellulose concentration, substituent types, and operating temperature on the electrochemical performance, demonstrating an obvious capacity loss up to 90% approximately of its initial value. Moreover, this is a cost-effective approach that has the potential for use in practical electrochemical storage devices.

G254: USU student payload flown on STS-64 in September, 1994

NASA Technical Reports Server (NTRS)

Raghuram, Tumkur; Monje, Oscar A.; Evans, Brett; Droter, Matt; Lemon, Mark; Redd, Kristen; Hubble, Tina; Wilkinson, Mark; Wilkinson, Michael; Tebbs, Dan

1995-01-01

G254 is the culmination of USU Get Away Special (GAS) students' efforts to get back into space. After a hiatus of a decade, the USU GAS program flew its sixth canister on STS-64 in September 1994. Like its predecessor payloads, this one contained a diverse set of experiments, six in all. Each experiment has its own lessons learned, which hopefully can be passed on to the next generation of GAS students. This presentation will give a balanced view of the successes and failures of G254. Emphasis will be placed on describing the stumbling blocks and the many lessons learned that come from experience rather than academic training. G254 has once again taken a team of about fifteen USU students, plus about one hundred fourth and fifth graders, and given them an immeasurable education.

Correlated pay-offs are key to cooperation

PubMed Central

Frommen, Joachim G.; Riehl, Christina

2016-01-01

The general belief that cooperation and altruism in social groups result primarily from kin selection has recently been challenged, not least because results from cooperatively breeding insects and vertebrates have shown that groups may be composed mainly of non-relatives. This allows testing predictions of reciprocity theory without the confounding effect of relatedness. Here, we review complementary and alternative evolutionary mechanisms to kin selection theory and provide empirical examples of cooperative behaviour among unrelated individuals in a wide range of taxa. In particular, we focus on the different forms of reciprocity and on their underlying decision rules, asking about evolutionary stability, the conditions selecting for reciprocity and the factors constraining reciprocal cooperation. We find that neither the cognitive requirements of reciprocal cooperation nor the often sequential nature of interactions are insuperable stumbling blocks for the evolution of reciprocity. We argue that simple decision rules such as ‘help anyone if helped by someone’ should get more attention in future research, because empirical studies show that animals apply such rules, and theoretical models find that they can create stable levels of cooperation under a wide range of conditions. Owing to its simplicity, behaviour based on such a heuristic may in fact be ubiquitous. Finally, we argue that the evolution of exchange and trading of service and commodities among social partners needs greater scientific focus. PMID:26729924

Information technology in health care--what the future holds.

PubMed

Bulgiba, A M

2004-01-01

In 1998, Malaysia opened its first hospital based on the "paperless and filmless" concept. Two are now in operation, with more to follow. Telemedicine is now being used in some hospitals and is slated to be the technology to watch. Future use of technology in health care will centre on the use of centralised patient databases and more effective use of artificial intelligence. Stumbling blocks include the enormous capital costs involved and difficulty in getting sufficient bandwidth to support applications on a national scale. Problems with the use of information technology in developing countries still remain; mainly inadequate skilled resources to operate and maintain the technology, lack of home-grown technology, insufficient experience in the use of information technology in health care and the attitudes of some health staff. The challenge for those involved in this field will not be in building new "paperless and filmless" institutions but in transforming current "paper and film-based" institutions to "paperless and filmless" ones and changing the mindset of health staff. Universities and medical schools must be prepared to respond to this new wave by incorporating elements of medical/health informatics in their curriculum and assisting governments in the planning and implementation of these projects. The experience of the UMMC is highlighted as an example of the difficulty of transforming a paper-based hospital to a "paperless and filmless" hospital.

Endgame: engaging the tobacco industry in its own elimination.

PubMed

Ioannidis, John P A; Henriksen, Lisa; Prochaska, Judith J

2013-12-01

A billion deaths from tobacco are expected by 2100. Many policy interventions such as increased taxation, restrictions on advertisement, smoking bans, as well as behavioral interventions, such as pharmacological and psychological treatments for smoking cessation, decrease tobacco use, but they reach their limits. Endgame scenarios focusing on tobacco supply rather than demand are increasingly discussed, but meet with resistance by the industry and even by many tobacco control experts. A main stumbling block that requires more attention is what to do with the tobacco industry in endgame scenarios. This industry has employed notoriously talented experts in law, business, organization, marketing, advertising, strategy, policy, and statistics and has tremendous lobbying power. Performance-based regulatory approaches can pose a legal obligation on manufacturers to decrease - and eventually - eliminate tobacco products according to specified schedules. Penalties and rewards can make such plans both beneficial for public health and attractive to the companies that do the job well. We discuss caveats and reality checks of engaging the tobacco industry to eliminate its current market and change focus. Brainstorming is warranted to entice the industry to abandon tobacco for other profit goals. To get the dialogue started, we propose the wild possibility of hiring former tobacco companies to reduce the costs of healthcare, thereby addressing concurrently two major challenges to public health. © 2013 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.

Life cycle assessment of automobile/fuel options.

PubMed

MacLean, Heather L; Lave, Lester B

2003-12-01

We examine the possibilities for a "greener" car that would use less material and fuel, be less polluting, and would have a well-managed end-of-life. Light-duty vehicles are fundamental to our economy and will continue to be for the indefinite future. Any redesign to make these vehicles greener requires consumer acceptance. Consumer desires for large, powerful vehicles have been the major stumbling block in achieving a "green car". The other major barrier is inherent contradictions among social goals such as fuel economy, safety, low emissions of pollutants, and low emissions of greenhouse gases, which has led to conflicting regulations such as emissions regulations blocking sales of direct injection diesels in California, which would save fuel. In evaluating fuel/vehicle options with the potential to improve the greenness of cars [diesel (direct injection) and ethanol in internal combustion engines, battery-powered, gasoline hybrid electric, and hydrogen fuel cells], we find no option dominates the others on all dimensions. The principles of green design developed by Anastas and Zimmerman (Environ. Sci. Technol. 2003, 37, 94A-101A) and the use of a life cycle approach provide insights on the key sustainability issues associated with the various options.

The analysis of convolutional codes via the extended Smith algorithm

NASA Technical Reports Server (NTRS)

Mceliece, R. J.; Onyszchuk, I.

1993-01-01

Convolutional codes have been the central part of most error-control systems in deep-space communication for many years. Almost all such applications, however, have used the restricted class of (n,1), also known as 'rate 1/n,' convolutional codes. The more general class of (n,k) convolutional codes contains many potentially useful codes, but their algebraic theory is difficult and has proved to be a stumbling block in the evolution of convolutional coding systems. In this article, the situation is improved by describing a set of practical algorithms for computing certain basic things about a convolutional code (among them the degree, the Forney indices, a minimal generator matrix, and a parity-check matrix), which are usually needed before a system using the code can be built. The approach is based on the classic Forney theory for convolutional codes, together with the extended Smith algorithm for polynomial matrices, which is introduced in this article.

Achieving Transformational Materials Performance in a New Era of Science

ScienceCinema

Sarrao, John

2017-12-22

The inability of current materials to meet performance requirements is a key stumbling block for addressing grand challenges in energy and national security. Fortunately, materials research is on the brink of a new era - a transition from observation and validation of materials properties to prediction and control of materials performance. In this talk, I describe the nature of the current challenge, the prospects for success, and a specific facility concept, MaRIE, that will provide the needed capabilities to meet these challenges, especially for materials in extreme environments. MaRIE, for Matter-Radiation Interactions in Extremes, is Los Alamos' concept to realize this vision of 21st century materials research. This vision will be realized through enhancements to the current LANSCE accelerator, development of a fourth-generation x-ray light source co-located with the proton accelerator, and a comprehensive synthesis and characterization facility focused on controlling complex materials and the defect/structure link to materials performance.

Real-Time Communication Support for Underwater Acoustic Sensor Networks †.

PubMed

Santos, Rodrigo; Orozco, Javier; Micheletto, Matias; Ochoa, Sergio F; Meseguer, Roc; Millan, Pere; Molina, And Carlos

2017-07-14

Underwater sensor networks represent an important and promising field of research due to the large diversity of underwater ubiquitous applications that can be supported by these networks, e.g., systems that deliver tsunami and oil spill warnings, or monitor submarine ecosystems. Most of these monitoring and warning systems require real-time communication in wide area networks that have a low density of nodes. The underwater communication medium involved in these networks is very harsh and imposes strong restrictions to the communication process. In this scenario, the real-time transmission of information is done mainly using acoustic signals, since the network nodes are not physically close. The features of the communication scenario and the requirements of the communication process represent major challenges for designers of both, communication protocols and monitoring and warning systems. The lack of models to represent these networks is the main stumbling block for the proliferation of underwater ubiquitous systems. This paper presents a real-time communication model for underwater acoustic sensor networks (UW-ASN) that are designed to cover wide areas with a low density of nodes, using any-to-any communication. This model is analytic, considers two solution approaches for scheduling the real-time messages, and provides a time-constraint analysis for the network performance. Using this model, the designers of protocols and underwater ubiquitous systems can quickly prototype and evaluate their solutions in an evolving way, in order to determine the best solution to the problem being addressed. The suitability of the proposal is illustrated with a case study that shows the performance of a UW-ASN under several initial conditions. This is the first analytic model for representing real-time communication in this type of network, and therefore, it opens the door for the development of underwater ubiquitous systems for several application scenarios.

Real-Time Communication Support for Underwater Acoustic Sensor Networks †

PubMed Central

Santos, Rodrigo; Orozco, Javier; Micheletto, Matias

2017-01-01

Underwater sensor networks represent an important and promising field of research due to the large diversity of underwater ubiquitous applications that can be supported by these networks, e.g., systems that deliver tsunami and oil spill warnings, or monitor submarine ecosystems. Most of these monitoring and warning systems require real-time communication in wide area networks that have a low density of nodes. The underwater communication medium involved in these networks is very harsh and imposes strong restrictions to the communication process. In this scenario, the real-time transmission of information is done mainly using acoustic signals, since the network nodes are not physically close. The features of the communication scenario and the requirements of the communication process represent major challenges for designers of both, communication protocols and monitoring and warning systems. The lack of models to represent these networks is the main stumbling block for the proliferation of underwater ubiquitous systems. This paper presents a real-time communication model for underwater acoustic sensor networks (UW-ASN) that are designed to cover wide areas with a low density of nodes, using any-to-any communication. This model is analytic, considers two solution approaches for scheduling the real-time messages, and provides a time-constraint analysis for the network performance. Using this model, the designers of protocols and underwater ubiquitous systems can quickly prototype and evaluate their solutions in an evolving way, in order to determine the best solution to the problem being addressed. The suitability of the proposal is illustrated with a case study that shows the performance of a UW-ASN under several initial conditions. This is the first analytic model for representing real-time communication in this type of network, and therefore, it opens the door for the development of underwater ubiquitous systems for several application scenarios. PMID:28708093

History of oral contraception.

PubMed

Dhont, Marc

2010-12-01

On the 50th birthday of the pill, it is appropriate to recall the milestones which have led to its development and evolution during the last five decades. The main contraceptive effect of the pill being inhibition of ovulation, it may be called a small miracle that this drug was developed long before the complex regulation of ovulation and the menstrual cycle was elucidated. Another stumbling block on its way was the hostile climate with regard to contraception that prevailed at the time. Animal experiments on the effect of sex steroids on ovulation, and the synthesis of sex steroids and orally active analogues were the necessary preliminaries. We owe the development of oral contraceptives to a handful of persons: two determined feminists, Margaret Sanger and Katherine McCormick; a biologist, Gregory Pincus; and a gynaecologist, John Rock. Soon after the introduction of the first pills, some nasty and life-threatening side effects emerged, which were due to the high doses of sex steroids. This led to the development of new preparations with reduced oestrogen content, progestins with more specific action, and alternative administration routes. Almost every decade we have witnessed a breakthrough in oral contraception. Social and moral objections to birth control have gradually disappeared and, notwithstanding some pill scares, oral contraceptives are now one of the most used methods of contraception. Finally, all's well that ends well: recent reports have substantiated the multiple noncontraceptive health benefits paving the way for a bright future for this 50-year-old product.

Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee.

PubMed

Hafner, Brian J; Willingham, Laura L; Buell, Noelle C; Allyn, Katheryn J; Smith, Douglas G

2007-02-01

To evaluate differences in function, performance, and preference between mechanical and microprocessor prosthetic knee control technologies. A-B-A-B reversal design. Home, community, and laboratory environments. Twenty-one unilateral, transfemoral amputees. Mechanical control prosthetic knee versus microprocessor control prosthetic knee (Otto Bock C-Leg). Stair rating, hill rating and time, obstacle course time, divided attention task accuracy and time, Amputee Mobility Predictor score, step activity, Prosthesis Evaluation Questionnaire score, Medical Outcomes Study 36-Item Short-Form Health Survey score, self-reported frequency of stumbles and falls, and self-reported concentration required for ambulation. Stair descent score, hill descent time, and hill sound-side step length showed significant (P<.01) improvement with the C-Leg. Users reported a significant (P<.05) decrease in frequency of stumbles and falls, frustration with falling, and difficulty in multitasking while using the microprocessor knee. Subject satisfaction with the C-Leg was significantly (P<.001) greater than the mechanical control prosthesis. The study population showed improved performance when negotiating stairs and hills, reduced frequency of stumbling and falling, and a preference for the microprocessor control C-Leg as compared with the mechanical control prosthetic knee.

Exploring the integration of internationally educated occupational therapists into the workforce.

PubMed

Mulholland, Susan J; Dietrich, Tracy A; Bressler, Sandra I; Corbett, Kathy G

2013-02-01

British Columbia (BC) is a popular Canadian work destination for occupational therapists from around the world. This study explored the experiences of stakeholders involved in the integration of internationally educated occupational therapists (IEOTs) into the BC workforce. Semi-structured interviews were conducted with the three primary stakeholder groups (40 IEOTs, 12 supervising occupational therapists, seven managers), as well as with seven key informants. Participants were purposively sampled and thematic analysis was applied to the data. Three themes were identified that fit sequentially along a workforce-integration continuum: "coming to Canada," "registering with the college," and "integrating into the workplace." Within those themes, findings were organized into two categories, "ingredients for success" and "stumbling block," and multiple subcategories. The findings suggest that hiring IEOTs can bring benefits to the workplace and clients. However, changes made along the continuum would facilitate workforce integration, ultimately benefiting all stakeholders. These findings may be of interest to IEOTs, occupational therapists, and managers as well as individuals working in regulation and policy.

Evaluation of the instream flow incremental methodology by U.S. Fish and Wildlife Service field users

USGS Publications Warehouse

Armour, Carl L.; Taylor, Jonathan G.

1991-01-01

This paper summarizes results of a survey conducted in 1988 of 57 U.S. Fish and Wildlife Service field offices. The purpose was to document opinions of biologists experienced in applying the Instream Flow Incremental Methodology (IFIM). Responses were received from 35 offices where 616 IFIM applications were reported. The existence of six monitoring studies designed to evaluate the adequacy of flows provided at sites was confirmed. The two principal categories reported as stumbling blocks to the successful application of IFIM were beliefs that the methodology is technically too simplistic or that it is too complex to apply. Recommendations receiving the highest scores for future initiatives to enhance IFIM use were (1) training and workshops for field biologists; and (2) improving suitability index (SI) curves and computer models, and evaluating the relationship of weighted useable area (WUA) to fish responses. The authors concur that emphasis for research should be on addressing technical concerns about SI curves and WUA.

Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio

NASA Astrophysics Data System (ADS)

Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert

2016-01-01

Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate.

Low-order modelling of a drop on a highly-hydrophobic substrate: statics and dynamics

NASA Astrophysics Data System (ADS)

Wray, Alexander W.; Matar, Omar K.; Davis, Stephen H.

2017-11-01

We analyse the behaviour of droplets resting on highly-hydrophobic substrates. This problem is of practical interest due to its appearance in many physical contexts involving the spreading, wetting, and dewetting of fluids on solid substrates. In mathematical terms, it exhibits an interesting challenge as the interface is multi-valued as a function of the natural Cartesian co-ordinates, presenting a stumbling block to typical low-order modelling techniques. Nonetheless, we show that in the static case, the interfacial shape is governed by the Young-Laplace equation, which may be solved explicitly in terms of elliptic functions. We present simple low-order expressions that faithfully reproduce the shapes. We then consider the dynamic case, showing that the predictions of our low-order model compare favourably with those obtained from direct numerical simulations. We also examine the characteristic flow regimes of interest. EPSRC, UK, MEMPHIS program Grant (EP/K003976/1), RAEng Research Chair (OKM).

The Fortran-P Translator: Towards Automatic Translation of Fortran 77 Programs for Massively Parallel Processors

DOE PAGES

O'keefe, Matthew; Parr, Terence; Edgar, B. Kevin; ...

1995-01-01

Massively parallel processors (MPPs) hold the promise of extremely high performance that, if realized, could be used to study problems of unprecedented size and complexity. One of the primary stumbling blocks to this promise has been the lack of tools to translate application codes to MPP form. In this article we show how applications codes written in a subset of Fortran 77, called Fortran-P, can be translated to achieve good performance on several massively parallel machines. This subset can express codes that are self-similar, where the algorithm applied to the global data domain is also applied to each subdomain. Wemore » have found many codes that match the Fortran-P programming style and have converted them using our tools. We believe a self-similar coding style will accomplish what a vectorizable style has accomplished for vector machines by allowing the construction of robust, user-friendly, automatic translation systems that increase programmer productivity and generate fast, efficient code for MPPs.« less

Wavelength-tunable entangled photons from silicon-integrated III-V quantum dots.

PubMed

Chen, Yan; Zhang, Jiaxiang; Zopf, Michael; Jung, Kyubong; Zhang, Yang; Keil, Robert; Ding, Fei; Schmidt, Oliver G

2016-01-27

Many of the quantum information applications rely on indistinguishable sources of polarization-entangled photons. Semiconductor quantum dots are among the leading candidates for a deterministic entangled photon source; however, due to their random growth nature, it is impossible to find different quantum dots emitting entangled photons with identical wavelengths. The wavelength tunability has therefore become a fundamental requirement for a number of envisioned applications, for example, nesting different dots via the entanglement swapping and interfacing dots with cavities/atoms. Here we report the generation of wavelength-tunable entangled photons from on-chip integrated InAs/GaAs quantum dots. With a novel anisotropic strain engineering technique based on PMN-PT/silicon micro-electromechanical system, we can recover the quantum dot electronic symmetry at different exciton emission wavelengths. Together with a footprint of several hundred microns, our device facilitates the scalable integration of indistinguishable entangled photon sources on-chip, and therefore removes a major stumbling block to the quantum-dot-based solid-state quantum information platforms.

Marketers approve check-off plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mantho, M.

1996-02-01

For the last several years, we have ended the year with a questionnaire looking into the future. Our panel was asked what was the greatest threat to our industry. Consistently, they have answered {open_quotes}the lack of real growth.{close_quotes} This year was no exception, but this time there was a feeling that something could and would be done. Almost every marketer (98%) said he or she supported the check-off program that would raise considerable funds for public relations and research. This idea isn`t new; it has been discussed year after year. Always the stumbling block was how to raise funds somore » that each company contributed and no one had a free ride. Last year, it was proposed that a commission created by federal law, be established to oversee funds for the education of consumers and government and provide technology research. If Congress authorizes this plan and members of the industry endorse it, we would have a strong program in place by 1997.« less

Protein crystal growth in microgravity: Temperature induced large scale crystallization of insulin

NASA Technical Reports Server (NTRS)

Long, Marianna M.; Delucas, Larry J.; Smith, C.; Carson, M.; Moore, K.; Harrington, Michael D.; Pillion, D. J.; Bishop, S. P.; Rosenblum, W. M.; Naumann, R. J.

1994-01-01

One of the major stumbling blocks that prevents rapid structure determination using x-ray crystallography is macro-molecular crystal growth. There are many examples where crystallization takes longer than structure determination. In some cases, it is impossible to grow useful crystals on earth. Recent experiments conducted in conjuction with NASA on various Space Shuttle missions have demonstrated that protein crystals often grow larger and display better internal molecular order than their earth-grown counterparts. This paper reports results from three Shuttle flights using the Protein Crystallization Facility (PCF). The PCF hardware produced large, high-quality insulin crystals by using a temperature change as the sole means to affect protein solubility and thus, crystallization. The facility consists of cylinders/containers with volumes of 500, 200, 100, and 50 ml. Data from the three Shuttle flights demonstrated that larger, higher resolution crystals (as evidenced by x-ray diffraction data) were obtained from the microgravity experiments when compared to earth-grown crystals.

Improving the feasibility of producing biofuels from microalgae using wastewater.

PubMed

Rawat, I; Bhola, V; Kumar, R Ranjith; Bux, F

2013-01-01

Biofuels have received much attention recently owing to energy consumption and environmental concerns. Despite many of the technologies being technically feasible, the processes are often too costly to be commercially viable. The major stumbling block to full-scale production of algal biofuels is the cost of upstream and downstream processes and environmental impacts such as water footprint and indirect greenhouse gas emissions from chemical nutrient production. The technoeconomics of biofuels production from microalgae is currently unfeasible due to the cost of inputs and productivities achieved. The use of a biorefinery approach sees the production costs reduced greatly due to utilization of waste streams for cultivation and the generation of several potential energy sources and value-added products while offering environmental protection. The use of wastewater as a production media, coupled with CO2 sequestration from flue gas greatly reduces the microalgal cultivation costs. Conversion of residual biomass and by-products, such as glycerol, for fuel production using an integrated approach potentially holds the key to near future commercial implementation of biofuels production.

Low latency network and distributed storage for next generation HPC systems: the ExaNeSt project

NASA Astrophysics Data System (ADS)

Ammendola, R.; Biagioni, A.; Cretaro, P.; Frezza, O.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Paolucci, P. S.; Pastorelli, E.; Pisani, F.; Simula, F.; Vicini, P.; Navaridas, J.; Chaix, F.; Chrysos, N.; Katevenis, M.; Papaeustathiou, V.

2017-10-01

With processor architecture evolution, the HPC market has undergone a paradigm shift. The adoption of low-cost, Linux-based clusters extended the reach of HPC from its roots in modelling and simulation of complex physical systems to a broader range of industries, from biotechnology, cloud computing, computer analytics and big data challenges to manufacturing sectors. In this perspective, the near future HPC systems can be envisioned as composed of millions of low-power computing cores, densely packed — meaning cooling by appropriate technology — with a tightly interconnected, low latency and high performance network and equipped with a distributed storage architecture. Each of these features — dense packing, distributed storage and high performance interconnect — represents a challenge, made all the harder by the need to solve them at the same time. These challenges lie as stumbling blocks along the road towards Exascale-class systems; the ExaNeSt project acknowledges them and tasks itself with investigating ways around them.

The Fold Analysis Challenge: A virtual globe-based educational resource

NASA Astrophysics Data System (ADS)

De Paor, Declan G.; Dordevic, Mladen M.; Karabinos, Paul; Tewksbury, Barbara J.; Whitmeyer, Steven J.

2016-04-01

We present an undergraduate structural geology laboratory exercise using the Google Earth virtual globe with COLLADA models, optionally including an interactive stereographic projection and JavaScript controls. The learning resource challenges students to identify bedding traces and estimate bedding orientation at several locations on a fold, to fit the fold axis and axial plane to stereographic projection data, and to fit a doubly-plunging fold model to the large-scale structure. The chosen fold is the Sheep Mountain Anticline, a Laramide uplift in the Big Horn Basin of Wyoming. We take an education research-based approach, guiding students through three levels of difficulty. The exercise aims to counter common student misconceptions and stumbling blocks regarding penetrative structures. It can be used in preparation for an in-person field trip, for post-trip reinforcement, or as a virtual field experience in an online-only course. Our KML scripts can be easily transferred to other fold structures around the globe.

Assessing the toxicity of Pb- and Sn-based perovskite solar cells in model organism Danio rerio

PubMed Central

Babayigit, Aslihan; Duy Thanh, Dinh; Ethirajan, Anitha; Manca, Jean; Muller, Marc; Boyen, Hans-Gerd; Conings, Bert

2016-01-01

Intensive development of organometal halide perovskite solar cells has lead to a dramatic surge in power conversion efficiency up to 20%. Unfortunately, the most efficient perovskite solar cells all contain lead (Pb), which is an unsettling flaw that leads to severe environmental concerns and is therefore a stumbling block envisioning their large-scale application. Aiming for the retention of favorable electro-optical properties, tin (Sn) has been considered the most likely substitute. Preliminary studies have however shown that Sn-based perovskites are highly unstable and, moreover, Sn is also enlisted as a harmful chemical, with similar concerns regarding environment and health. To bring more clarity into the appropriateness of both metals in perovskite solar cells, we provide a case study with systematic comparison regarding the environmental impact of Pb- and Sn-based perovskites, using zebrafish (Danio Rerio) as model organism. Uncovering an unexpected route of intoxication in the form of acidification, it is shown that Sn based perovskite may not be the ideal Pb surrogate. PMID:26759068

[The influence of the relationship between physicians and pharmaceutical companies on the patient from the point of view of policy-makers in Israel].

PubMed

Nissanholtz-Gannot, Rachel; Shani, Segev; Shvarts, Shifra

2010-11-01

The relationship between doctors and pharmaceutical companies is an integral part of the health system in Israel and the whole world. The mutual need for such a relationship requires us, as a society, to examine its influence on the individual and the system as a whole. This research examines the relationship from the points of view of the relevant parties within the health system and outside the health system (decision-makers). The authors used in-depth interviews and qualitative research methods in order to examine and understand the various positions of decision-makers. The position of the decision-makers, regarding all the aspects of this relationship, expresses their wishes and depends on their point of view. The impact of the relationship between the doctors and the pharmaceutical companies was examined with regard to the prescription behavior of the doctor. All the government representatives, all the physicians' representatives and those of the health funds, believe that the physicians' prescription behavior is impacted by the relationship. There are those who perceive this to be a negative trend and some doctors believe it to be a positive trend. With regard to possible harm to the patient, the parties believe that the relationship does not harm the patient, whereas most of the government representatives identify harm to the patients, both on the economic and health levels. The authors believe that the "influence" which exists or could exist on the part of the pharmaceutical companies is the main stumbling block in this relationship, which is expressed in the decision-makers' perspective.

Fibromyalgia

MedlinePlus

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Lupus

MedlinePlus

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Bleeding Disorders

MedlinePlus

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Menstrual Cycle

MedlinePlus

... functionality. ------------------------------------------------------------ Find a Health Center ------------------------------------------------------------ Share this page: Twitter MySpace Technorati Facebook StumbleUpon Delicious Email to friend ... such as 20002), address, state, or place Share Twitter Facebook Email to friend Embed Code Embed this ...

Mysterious object He2-90

NASA Image and Video Library

1999-12-01

Astronomers using NASA Hubble Space Telescope stumbled upon a mysterious object that grudgingly yielded clues to its identity. The object is classified as a planetary nebula, the glowing remains of a dying, lightweight star.

Unexpected weak interaction

NASA Astrophysics Data System (ADS)

2013-08-01

Stéphane Coen and Miro Erkintalo from the University of Auckland in New Zealand talk to Nature Photonics about their surprising findings regarding a weak long-range interaction they serendipitously stumbled upon while researching temporal cavity solitons.

Who cares about physics today? A marketing strategy for the survival of fundamental science and the benefit of society

NASA Astrophysics Data System (ADS)

Cannella, Umberto

2013-04-01

It is often said that the major stumbling block for doing scientific outreach is money because of funding issues. Ignoring that the true issue is the lack of time and/or inclination on the part of practicing scientists, this statement is too generic to be quantitative or even complete: in fact, as for every project or investment, the discussion should be based on context and impact. Initiatives are at hand to do outreach that cost nothing more than the budget already in place for a University, its Departments and its scientific research groups: it is more a matter of capitalizing existing assets at a University in a concerted way and taking full advantage of these assets by means of synergetic collaborations. I will describe one such collaboration among the School of Dance and the Astronomy and Physics Departments at the University of Maryland: the dance performance ``Gravity,'' inspired by gravitational-wave astronomy. Similar types of partnerships represent new promising ways of doing science communications according to what can be rightly called a marketing strategy (http://arxiv.org.abs/1210.0082).

Risk-based corrective action: Lessons for brownfields from the Illinois rulemaking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reott, R.T.; Grayson, E.L.

As attention focuses on the redevelopment of brownfield properties, increasing numbers of stakeholders realize that one of the major stumbling blocks to the use of brownfields properties is the uncertainty over future cleanup costs. In Illinois, the Pollution Control Board recently completed a three-year rulemaking which has provided a new, risk-based system for determining corrective action objectives. 35 Ill. Adm. Code {section} 742 (1997). Armed with this system, Illinois property owners and developers may assess potential cleanup exposure with less site investigation than in the past. Because the system may be implemented quickly and predictably, it functions well in amore » transactional context where speed is critical. This presentation highlights the features of the new Illinois system and identifies potential issues that other states might wish to consider when they evaluate their own programs. Many states are in the process of implementing risk-based corrective action for some or all of their site remediation programs. The lessons learned in Illinois may help these states implement these programs more efficiently and with fewer developmental costs.« less

Design and test of a capacitance detection circuit based on a transimpedance amplifier

NASA Astrophysics Data System (ADS)

Linfeng, Mu; Wendong, Zhang; Changde, He; Rui, Zhang; Jinlong, Song; Chenyang, Xue

2015-07-01

This paper presents a transimpedance amplifier (TIA) capacitance detection circuit aimed at detecting micro-capacitance, which is caused by ultrasonic stimulation applied to the capacitive micro-machined ultrasonic transducer (CMUT). In the capacitance interface, a TIA is adopted to amplify the received signal with a center frequency of 400 kHz, and finally detect ultrasound pressure. The circuit has a strong anti-stray property and this paper also studies the calculation of compensation capacity in detail. To ensure high resolution, noise analysis is conducted. After optimization, the detected minimum ultrasound pressure is 2.1 Pa, which is two orders of magnitude higher than the former. The test results showed that the circuit was sensitive to changes in ultrasound pressure and the distance between the CMUT and stumbling block, which also successfully demonstrates the functionality of the developed TIA of the analog-front-end receiver. Project supported by the National Natural Science Foundation of China (No. 61127008) and the Subsidized Program of the National High Technology Research and Development Program of China (No. 2011AA040404).

Determining informative priors for cognitive models.

PubMed

Lee, Michael D; Vanpaemel, Wolf

2018-02-01

The development of cognitive models involves the creative scientific formalization of assumptions, based on theory, observation, and other relevant information. In the Bayesian approach to implementing, testing, and using cognitive models, assumptions can influence both the likelihood function of the model, usually corresponding to assumptions about psychological processes, and the prior distribution over model parameters, usually corresponding to assumptions about the psychological variables that influence those processes. The specification of the prior is unique to the Bayesian context, but often raises concerns that lead to the use of vague or non-informative priors in cognitive modeling. Sometimes the concerns stem from philosophical objections, but more often practical difficulties with how priors should be determined are the stumbling block. We survey several sources of information that can help to specify priors for cognitive models, discuss some of the methods by which this information can be formalized in a prior distribution, and identify a number of benefits of including informative priors in cognitive modeling. Our discussion is based on three illustrative cognitive models, involving memory retention, categorization, and decision making.

Fiscal year 2013 energy department budget: Proposed investments in clean energy research

NASA Astrophysics Data System (ADS)

Balcerak, Ernie

2012-03-01

Energy and environmental research programs generally fared well in President Barack Obama's proposed budget for the Department of Energy (DOE) for fiscal year (FY) 2013. In his State of the Union address, Obama called for the United States to pursue an "all of the above" energy strategy that includes fossil fuels, as well as a variety of renewable sources of energy. The DOE budget request supports that strategy, Energy Secretary Steven Chu said in a 13 February press briefing announcing the budget proposal. The proposed budget gives DOE 27.2 billion overall, a 3.2% increase from the FY 2012 enacted budget (see Table 1). This budget "reflects some tough choices," Chu said. The proposed budget would cut 4 billion in subsidies for oil and gas companies; many Republican members of Congress have already indicated that they oppose such cuts, suggesting that congressional approval of this budget may run into stumbling blocks. The budget would also cut funding for research and development projects that are already attracting private-sector investment or that are not working, and would reduce some of the department's operational costs.

Some linguistic and pragmatic considerations affecting science reporting in English by non-native speakers of the language

PubMed Central

2012-01-01

Approximately 50% of publications in English peer reviewed journals are contributed by non-native speakers (NNS) of the language. Basic thought processes are considered to be universal yet there are differences in thought patterns and particularly in discourse management of writers with different linguistic and cultural backgrounds. The study highlights some areas of potential incompatibility in native and NNS processing of English scientific papers. Principles and conventions in generating academic discourse are considered in terms of frequently occurring failures of NNS to meet expectations of editors, reviewers, and readers. Major problem areas concern organization and flow of information, principles of cohesion and clarity, cultural constraints, especially those of politeness and negotiability of ideas, and the complicated area of English modality pragmatics. The aim of the paper is to sensitize NN authors of English academic reports to problem areas of discourse processing which are stumbling blocks, often affecting acceptance of manuscripts. The problems discussed are essential for acquiring pragmalinguistic and sociocultural competence in producing effective communication. PMID:23118596

Stereotypes as stumbling-blocks: how coping with stereotype threat affects life outcomes for people with physical disabilities.

PubMed

Silverman, Arielle M; Cohen, Geoffrey L

2014-10-01

Stereotype threat, the concern about being judged in light of negative stereotypes, causes underperformance in evaluative situations. However, less is known about how coping with stereotypes can aggravate underperformance over time. We propose a model in which ongoing stereotype threat experiences threaten a person's sense of self-integrity, which in turn prompts defensive avoidance of stereotype-relevant situations, impeding growth, achievement, and well-being. We test this model in an important but understudied population: the physically disabled. In Study 1, blind adults reporting higher levels of stereotype threat reported lower self-integrity and well-being and were more likely to be unemployed and to report avoiding stereotype-threatening situations. In Study 2's field experiment, blind students in a compensatory skill-training program made more progress if they had completed a values-affirmation, an exercise that bolsters self-integrity. The findings suggest that stereotype threat poses a chronic threat to self-integrity and undermines life outcomes for people with disabilities. © 2014 by the Society for Personality and Social Psychology, Inc.

Lessons learned on the Ground Test Accelerator control system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozubal, A.J.; Weiss, R.E.

1994-09-01

When we initiated the control system design for the Ground Test Accelerator (GTA), we envisioned a system that would be flexible enough to handle the changing requirements of an experimental project. This control system would use a developers` toolkit to reduce the cost and time to develop applications for GTA, and through the use of open standards, the system would accommodate unforeseen requirements as they arose. Furthermore, we would attempt to demonstrate on GTA a level of automation far beyond that achieved by existing accelerator control systems. How well did we achieve these goals? What were the stumbling blocks tomore » deploying the control system, and what assumptions did we make about requirements that turned out to be incorrect? In this paper we look at the process of developing a control system that evolved into what is now the ``Experimental Physics and Industrial Control System`` (EPICS). Also, we assess the impact of this system on the GTA project, as well as the impact of GTA on EPICS. The lessons learned on GTA will be valuable for future projects.« less

Whole-body and Whole-Organ Clearing and Imaging Techniques with Single-Cell Resolution: Toward Organism-Level Systems Biology in Mammals.

PubMed

Susaki, Etsuo A; Ueda, Hiroki R

2016-01-21

Organism-level systems biology aims to identify, analyze, control and design cellular circuits in organisms. Many experimental and computational approaches have been developed over the years to allow us to conduct these studies. Some of the most powerful methods are based on using optical imaging in combination with fluorescent labeling, and for those one of the long-standing stumbling blocks has been tissue opacity. Recently, the solutions to this problem have started to emerge based on whole-body and whole-organ clearing techniques that employ innovative tissue-clearing chemistry. Here, we review these advancements and discuss how combining new clearing techniques with high-performing fluorescent proteins or small molecule tags, rapid volume imaging and efficient image informatics is resulting in comprehensive and quantitative organ-wide, single-cell resolution experimental data. These technologies are starting to yield information on connectivity and dynamics in cellular circuits at unprecedented resolution, and bring us closer to system-level understanding of physiology and diseases of complex mammalian systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

A virus-MIPs fluorescent sensor based on FRET for highly sensitive detection of JEV.

PubMed

Liang, Caishuang; Wang, Huan; He, Kui; Chen, Chunyan; Chen, Xiaoming; Gong, Hang; Cai, Changqun

2016-11-01

Major stumbling blocks in the recognition and detection of virus are the unstable biological recognition element or the complex detection means. Here a fluorescent sensor based on virus-molecular imprinted polymers (virus-MIPs) was designed for specific recognition and highly sensitive detection of Japanese encephalitis virus (JEV). The virus-MIPs were anchored on the surface of silica microspheres modified by fluorescent dye, pyrene-1-carboxaldehyde (PC). The fluorescence intensity of PC can be enhanced by the principle of fluorescence resonance energy transfer (FRET), where virus acted as energy donor and PC acted as energy acceptor. The enhanced fluorescence intensity was proportional to the concentration of virus in the range of 24-960pM, with a limit of detection (LOD, 3σ) of 9.6pM, and the relative standard deviation was 1.99%. In additional, the specificity study confirmed the resultant MIPs has high-selectivity for JEV. This sensor would become a new key for the detection of virus because of its high sensitive, simple operation, high stability and low cost. Copyright © 2016. Published by Elsevier B.V.

Trends in modern system theory

NASA Technical Reports Server (NTRS)

Athans, M.

1976-01-01

The topics considered are related to linear control system design, adaptive control, failure detection, control under failure, system reliability, and large-scale systems and decentralized control. It is pointed out that the design of a linear feedback control system which regulates a process about a desirable set point or steady-state condition in the presence of disturbances is a very important problem. The linearized dynamics of the process are used for design purposes. The typical linear-quadratic design involving the solution of the optimal control problem of a linear time-invariant system with respect to a quadratic performance criterion is considered along with gain reduction theorems and the multivariable phase margin theorem. The stumbling block in many adaptive design methodologies is associated with the amount of real time computation which is necessary. Attention is also given to the desperate need to develop good theories for large-scale systems, the beginning of a microprocessor revolution, the translation of the Wiener-Hopf theory into the time domain, and advances made in dynamic team theory, dynamic stochastic games, and finite memory stochastic control.

Curcumin on the "flying carpets" to modulate different signal transduction cascades in cancers: Next-generation approach to bridge translational gaps.

PubMed

Celik, Hulya; Aydin, Tuba; Solak, Kubra; Khalid, Sumbul; Farooqi, Ammad A

2018-06-01

Curcumin, a bioactive and pharmacologically efficient component isolated from Curcuma longa has attracted considerable attention because of its ability to modulate diverse cellular and physiological pathways. WNT, TGF/SMAD, NOTCH, and SHH are fundamentally different signaling cascades, but their choreographed activation is strongly associated with cancer development and progression. In this review we have attempted to set spotlight on regulation of different cell signaling pathways by curcumin in different cancers. We partition this multi-component review into in-depth biological understanding of various signal transduction cascades and how curcumin targets intracellular signal transducers of deregulated pathways to inhibit cancer development and progression. Rapidly broadening landscape of both established and candidate oncogenic driver mutations identified in different cancers is a major stumbling block in the standardization of drugs having significant clinical outcome. Intra and inter-tumor heterogeneity had leveraged the complexity of therapeutic challenges to another level. Multi-pronged approach and molecularly guided treatments will be helpful in improving the clinical outcome. © 2018 Wiley Periodicals, Inc.

Determining robot actions for tasks requiring sensor interaction

NASA Technical Reports Server (NTRS)

Budenske, John; Gini, Maria

1989-01-01

The performance of non-trivial tasks by a mobile robot has been a long term objective of robotic research. One of the major stumbling blocks to this goal is the conversion of the high-level planning goals and commands into the actuator and sensor processing controls. In order for a mobile robot to accomplish a non-trivial task, the task must be described in terms of primitive actions of the robot's actuators. Most non-trivial tasks require the robot to interact with its environment; thus necessitating coordination of sensor processing and actuator control to accomplish the task. The main contention is that the transformation from the high level description of the task to the primitive actions should be performed primarily at execution time, when knowledge about the environment can be obtained through sensors. It is proposed to produce the detailed plan of primitive actions by using a collection of low-level planning components that contain domain specific knowledge and knowledge about the available sensors, actuators, and sensor/actuator processing. This collection will perform signal and control processing as well as serve as a control interface between an actual mobile robot and a high-level planning system. Previous research has shown the usefulness of high-level planning systems to plan the coordination of activities such to achieve a goal, but none have been fully applied to actual mobile robots due to the complexity of interacting with sensors and actuators. This control interface is currently being implemented on a LABMATE mobile robot connected to a SUN workstation and will be developed such to enable the LABMATE to perform non-trivial, sensor-intensive tasks as specified by a planning system.

Methods for the development of a bioregenerative life support system

NASA Technical Reports Server (NTRS)

Goldman, Michelle; Gomez, Shawn; Voorhees, Mike

1990-01-01

Presented here is a rudimentary approach to designing a life support system based on the utilization of plants and animals. The biggest stumbling block in the initial phases of developing a bioregenerative life support system is encountered in collecting and consolidating the data. If a database existed for the systems engineer so that he or she may have accurate data and a better understanding of biological systems in engineering terms, then the design process would be simplified. Also addressed is a means of evaluating the subsystems chosen. These subsystems are unified into a common metric, kilograms of mass, and normalized in relation to the throughput of a few basic elements. The initial integration of these subsystems is based on input/output masses and eventually balanced to a point of operation within the inherent performance ranges of the organisms chosen. At this point, it becomes necessary to go beyond the simplifying assumptions of simple mass relationships and further define for each organism the processes used to manipulate the throughput matter. Mainly considered here is the fact that these organisms perform input/output functions on differing timescales, thus establishing the need for buffer volumes or appropriate subsystem phasing. At each point in a systematic design it is necessary to disturb the system and discern its sensitivity to the disturbance. This can be done either through the introduction of a catastrophic failure or by applying a small perturbation to the system. One example is increasing the crew size. Here the wide range of performance characteristics once again shows that biological systems have an inherent advantage in responding to systemic perturbations. Since the design of any space-based system depends on mass, power, and volume requirements, each subsystem must be evaluated in these terms.

An Organic Decontamination Method for Sampling Devices used in Life-detection Studies

NASA Technical Reports Server (NTRS)

Eigenbrode, Jennifer; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E.F.

2008-01-01

Organic decontamination of sampling and storage devices are crucial steps for life-detection, habitability, and ecological investigations of extremophiles living in the most inhospitable niches of Earth, Mars and elsewhere. However, one of the main stumbling blocks for Mars-analogue life-detection studies in terrestrial remote field-sites is the capability to clean instruments and sampling devices to organic levels consistent with null values. Here we present a new seven-step, multi-reagent cleaning and decontamination protocol that was adapted and tested on a glacial ice-coring device and on a rover-guided scoop used for sediment sampling both deployed multiple times during two field seasons of the Arctic Mars Analog Svalbard Expedition AMASE). The effectiveness of the protocols for both devices was tested by (1)in situ metabolic measurements via APT, (2)in situ lipopolysacchride (LPS) quantifications via low-level endotoxin assays, and(3) laboratory-based molecular detection via gas chromatography-mass spectrometry. Our results show that the combination and step-wise application of disinfectants with oxidative and solvation properties for sterilization are effective at removing cellular remnants and other organic traces to levels necessary for molecular organic- and life-detection studies. The validation of this seven-step protocol - specifically for ice sampling - allows us to proceed with confidence in kmskia4 analogue investigations of icy environments. However, results from a rover scoop test showed that this protocol is also suitable for null-level decontamination of sample acquisition devices. Thus, this protocol may be applicable to a variety of sampling devices and analytical instrumentation used for future astrobiology missions to Enceladus, and Europa, as well as for sample-return missions.

Unified Field Mechanics: A Brief Introduction

NASA Astrophysics Data System (ADS)

Amoroso, Richard L.

Recently we hear more and more physicists saying, `spacetime is doomed', `spacetime is a mirage', the `end of spacetime', `spacetime is not fundamental but emergent' etc. "Henceforth space by itself and time by itself are doomed to fade into the mere shadows, and only a union of the two will preserve an independent reality." - 1908 Hermann Minkowski. We have come full circle from the time of Minkowski's 1908 statement to the brink of an imminent new age of discovery. The basis of our understanding of the natural world has evolved in modern times from Newtonian Mechanics to the 2nd regime of Quantum Mechanics; and now to the threshold of a 3rd regime - Unified Field Mechanics (UFM). The Planck scale stochastic quantum realm can no longer be considered the `basement' or fundamental level of reality. As hard as quantum reality was to imagine so is the fact that the quantum domain is a manifold of finite radius; and that the `sacrosanct - indelible' Quantum Uncertainty Principle can now be surmounted. For decades main stream physicists have been stymied by efforts to reconcile General Relativity with Quantum Mechanics. The stumbling block lies with the two theories conflicting views of space and time: For quantum theory, space and time offer a fixed backcloth against which particles move. In Einstein's relativities, space and time are not only inextricably linked, but the resultant spacetime is warped by the matter within it. In our nascent UFM paradigm for arcane reasons the quantum manifold is not the regime of integration with gravity; it is instead integrated with the domain of the unified field where the forces of nature are deemed to unify. We give a simplistic survey of the fundamental premises of UFM and summarize experimental protocols to falsify the model at this stage of the paradigm's development.

Biomechanical behavior of a cemented ceramic knee replacement under worst case scenarios

NASA Astrophysics Data System (ADS)

Kluess, D.; Mittelmeier, W.; Bader, R.

2009-12-01

In connection with technological advances in the manufacturing of medical ceramics, a newly developed ceramic femoral component was introduced in total knee arthroplasty (TKA). The motivation to consider ceramics in TKA is based on the allergological and tribological benefits as proven in total hip arthroplasty. Owing to the brittleness and reduced fracture toughness of ceramic materials, the biomechanical performance has to be examined intensely. Apart from standard testing, we calculated the implant performance under different worst case scenarios including malposition, bone defects and stumbling. A finite-element-model was developed to calculate the implant performance in situ. The worst case conditions revealed principal stresses 12.6 times higher during stumbling than during normal gait. Nevertheless, none of the calculated principal stress amounts were above the critical strength of the ceramic material used. The analysis of malposition showed the necessity of exact alignment of the implant components.

Biomechanical behavior of a cemented ceramic knee replacement under worst case scenarios

NASA Astrophysics Data System (ADS)

Kluess, D.; Mittelmeier, W.; Bader, R.

2010-03-01

In connection with technological advances in the manufacturing of medical ceramics, a newly developed ceramic femoral component was introduced in total knee arthroplasty (TKA). The motivation to consider ceramics in TKA is based on the allergological and tribological benefits as proven in total hip arthroplasty. Owing to the brittleness and reduced fracture toughness of ceramic materials, the biomechanical performance has to be examined intensely. Apart from standard testing, we calculated the implant performance under different worst case scenarios including malposition, bone defects and stumbling. A finite-element-model was developed to calculate the implant performance in situ. The worst case conditions revealed principal stresses 12.6 times higher during stumbling than during normal gait. Nevertheless, none of the calculated principal stress amounts were above the critical strength of the ceramic material used. The analysis of malposition showed the necessity of exact alignment of the implant components.

Occupational accident and disease claims, work-related stress and job satisfaction of physiotherapists.

PubMed

Brattig, Birte; Schablon, Anja; Nienhaus, Albert; Peters, Claudia

2014-01-01

Physiotherapists are exposed to diverse occupational demands. Until now, little has been known about the interaction between occupational stress and the job satisfaction of physiotherapists. This paper aims to examine their work-related stress and job satisfaction. It will analyse accidents at work and occupational diseases of physiotherapists along with work-related physical and psychosocial stress and job satisfaction. We analysed routine data of the German Institute for Statutory Accident Insurance and Prevention in the Health and Welfare Services (BGW) on accidents at work and occurring en route to/from work as well as occupational diseases of physiotherapists. Work-related stress and job satisfaction were examined in a cross-sectional survey using a standard questionnaire to be completed by subjects themselves. Between 2007 and 2011, 1,229 cases of occupational disease were reported to the BGW. The majority of reports involved skin diseases (73%). Stumbles and falls were the most frequent causes of accidents at work (42.9%). Eighty-five physiotherapists all over Germany took part in the survey. They experience high quantitative demands at work. The main physical demands consist of a torso posture between 45° and 90° and high hand activity. Of the 85 subjects, 51% suffer from complaints of the musculoskeletal system in the neck and thoracic spine area and 24% have skin diseases. Most physiotherapists (88%) are satisfied with their work overall. This is aided by a high degree of influence on their work and breaks, by practical application of skills and expert knowledge, high regard for their profession, varied work and a good atmosphere at work. Reservations tend to be about statutory regulations and the social benefits provided by the German healthcare system. Overall, despite high demands and stress relating to the adequacy of resources, the majority of physiotherapists surveyed seem to be satisfied with their job. The main focus of action to promote the health of physiotherapists should be on preventing skin disease, problems of the musculoskeletal system and accidents caused by stumbles and falls.

A method to simulate motor control strategies to recover from perturbations: application to a stumble recovery during gait.

PubMed

Forner-Cordero, Arturo; Ackermann, Marko; de Lima Freitas, Mateus

2011-01-01

Perturbations during human gait such as a trip or a slip can result in a fall, especially among frail populations such as the elderly. In order to recover from a trip or a stumble during gait, humans perform different types of recovery strategies. It is very useful to uncover the mechanisms of the recovery to improve training methods for populations at risk of falling. Moreover, human recovery strategies could be applied to implement controllers for bipedal robot walker, as an application of biomimetic design. A biomechanical model of the response to a trip during gait might uncover the control mechanisms underlying the different recovery strategies and the adaptation of the responses found during the execution of successive perturbation trials. This paper introduces a model of stumble in the multibody system framework. This model is used to assess different feedforward strategies to recover from a trip. First of all, normal gait patterns for the musculoskeletal system model are obtained by solving an optimal control problem. Secondly, the reference gait is perturbed by the application of forces on the swinging foot in different ways: as an instantaneous inelastic collision of the foot with an obstacle, as an impulsive horizontal force or using a force curve measured experimentally during gait perturbation experiments. The influence of the type of perturbation, the timing of the collision with respect to the gait cycle, as well as of the coefficient of restitution was investigated previously. Finally, in order to test the effects of different muscle excitation levels on the initial phases of the recovery response, several muscle excitations were added to selected muscles of the legs, thus providing a simulation of the recovery reactions. These results pave the way for future analysis and modeling of the control mechanisms of gait.

Promoting critical thinking and academic writing skills in nurse education.

PubMed

Borglin, Gunilla

2012-07-01

Although academic skills, conceptualised as writing and critical thinking, are a vital part of university studies, research indicates that many students leave without having mastered these skills effectively. This research also reflects on nursing students. Nursing could also be said to be hampered by a number of complex educational challenges that are likely to impact on the academic socialisation process in general. These challenges include being a relatively 'young' academic discipline, the 'theory-practice' divide, a knowledge bed lying on a complex intersection of two 'antithetical sciences' and, at least in the Scandinavian countries, an increasing number of nurse educators with a PhD in nursing science but with limited time to develop their own teaching skills. In combination, these challenges have the potential to act as stumbling blocks, both from a teaching and learning perspective. I would suggest that a departure in teaching from theoretical educational models, such as Lea and Street's 'academic literacies model,' including skills, socialisation and academic literacy models simultaneously, could be one of several ways forward to create a learning environment that takes these issues into account. Copyright © 2011 Elsevier Ltd. All rights reserved.

Stepping stone or stumbling block? Mode 2 knowledge production in sustainability science.

PubMed

Thorén, Henrik; Breian, Line

2016-04-01

The concept of Mode 2 has often been seen as especially applicable to fields addressing grand challenges, such as climate change. Being a relatively new field-interdisciplinary in its approach, and focused on addressing such issues-sustainability science would appear to be a case in point. The aim of this paper is twofold: 1) to explore the perceived relation between Mode 2 and sustainability science, and 2) to advance the discussion of Mode 2 from a philosophical perspective. To address these questions we focus on three characteristic features of Mode 2: the notion of a distinct, but evolving framework; boundary crossing; and a problem solving capacity "on the move". We report the results of a survey carried out amongst leading sustainability scientists. The survey gives insight into the scientists' perception of Mode 2, their perception of their own field of sustainability science and the relation between the two. The free text answers reveal a tension within the field of sustainability science: with developments both towards Mode 1 and Mode 2 science. We conclude that the implementation of inter- and trans-disciplinarity is challenged by institutional and conceptual factors alike. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tuberculous meningitis: a uniform case definition for use in clinical research.

PubMed

Marais, Suzaan; Thwaites, Guy; Schoeman, Johan F; Török, M Estée; Misra, Usha K; Prasad, Kameshwar; Donald, Peter R; Wilkinson, Robert J; Marais, Ben J

2010-11-01

Tuberculous meningitis causes substantial mortality and morbidity in children and adults. More research is urgently needed to better understand the pathogenesis of disease and to improve its clinical management and outcome. A major stumbling block is the absence of standardised diagnostic criteria. The different case definitions used in various studies makes comparison of research findings difficult, prevents the best use of existing data, and limits the management of disease. To address this problem, a 3-day tuberculous meningitis workshop took place in Cape Town, South Africa, and was attended by 41 international participants experienced in the research or management of tuberculous meningitis. During the meeting, diagnostic criteria were assessed and discussed, after which a writing committee was appointed to finalise a consensus case definition for tuberculous meningitis for use in future clinical research. We present the consensus case definition together with the rationale behind the recommendations. This case definition is applicable irrespective of the patient's age, HIV infection status, or the resources available in the research setting. Consistent use of the proposed case definition will aid comparison of studies, improve scientific communication, and ultimately improve care. Copyright © 2010 Elsevier Ltd. All rights reserved.

The skills gap in nursing management in South Africa: a sectoral analysis: a research paper.

PubMed

Pillay, Rubin

2010-03-01

To identify competencies important for effective nursing management and to assess managers' proficiency therein. A lack of management capacity has been identified as the key stumbling block to health delivery in South Africa. Despite nursing managers being central to overcoming the challenges facing health care, there has been a paucity of research that empirically evaluates their skill levels. A survey was conducted among 171 senior nursing managers in South Africa using a self-administered questionnaire. Public sector managers assessed themselves as being relatively less competent than private sector managers. The largest skill gaps for public sector managers were for 'ethico-legal', 'task-related' and 'controlling' skills whereas those for private sector managers were for 'ethico-legal', 'health-related ' and 'task-related' skills. This research confirmed the lack of management capacity within the health sector and identified areas in which the skills deficit was most significant for both the public and private sectors. These findings reflect the needs of nursing managers and will be useful in the conceptualization, design and delivery of health management programmes aimed at enhancing management and leadership capacity in the health sector in South Africa.

The evolution of concepts for soil erosion modelling

NASA Astrophysics Data System (ADS)

Kirkby, Mike

2013-04-01

From the earliest models for soil erosion, based on power laws relating sediment discharge or yield to slope length and gradient, the development of the Universal Soil Loss Equation was a natural step, although one that has long continued to hinder the development of better perceptual models for erosion processes. Key stumbling blocks have been: 1. The failure to go through runoff generation as a key intermediary 2. The failure to separate hydrological and strength parameters of the soil 3. The failure to treat sediment transport along a slope as a routing problem 4. The failure to analyse the nature of the dependence on vegetation Key advances have been in these directions (among others) 1. Improved understanding of the hydrological processes (e.g. infiltration and runoff, sediment entrainment) leading to KINEROS, LISEM,WEPP, PESERA 2. Recognition of selective sediment transport (e.g. transport- or supply-limited removal, grain travel distances) leading e.g. to MAHLERAN 3. Development of models adapted to particular time/space scales Some major remaining problems 1. Failure to integrate geomorphological and agronomic approaches 2. Tillage erosion - Is erosion loss of sediment or lowering of centre of mass? 3. Dynamic change during an event, as rills etc form.

SLAYING THE DRAGON-THE STORY OF ONE FPSO, 20 VIETNAMESE OPERATORS AND 3 CONCRETE MIXERS.

PubMed

O'Brien, Anthony; van Rooyen, Annelize

2017-04-01

End of life of a floating production, storage and offloading (FPSO) facility requires a lot of planning and management. One of the major challenges is the issue of decontamination and waste management. Waste disposal is a very sensitive subject and with agreements like the London Protocol and differences in legislation between countries, it has the potential to become a major stumbling block. Radiation safety is something not often on the mind of an FPSO operator. The planning and layout of such a vessel and its processing plant have usually not gone through any as low as reasonably achievable process during design. Planning the decontamination of such a vessel should start long before the actual decommissioning date. Performing regular vessel cleanouts and radiological profiling of the plant can be beneficial in the end. Finding a workable solution in getting naturally occurring radioactive material contaminated waste out of the vessels and tanks and effectively reducing the waste volumes for end of life clean-up is very important. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Endocrine Disruptors

PubMed Central

2015-01-01

Law and science combine in the estimation of risks from endocrine disruptors (EDs) and actions for their regulation. For both, dose–response models are the causal link between exposure and probability (or percentage change) of adverse response. The evidence that leads to either regulations or judicial decrees is affected by uncertainty and limited knowledge, raising difficult policy issues that we enumerate and discuss. In the United States, some courts have dealt with EDs, but causation based on animal studies has been a stumbling block for plaintiffs seeking compensation, principally because those courts opt for epidemiological evidence. The European Union (EU) has several regulatory tools and ongoing research on the risks associated with bisphenol A, under the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) Regulation and other regulations or directives. The integration of a vast (in kind and in scope) number of research papers into a statement of causation for either policy or to satisfy legal requirements, in both the United States and the EU, relies on experts. We outline the discursive dilemma and issues that may affect consensus-based results and a Bayesian causal approach that accounts for the evolution of information, yielding both value of information and flexibility associated with public choices. PMID:26740809

In situ assembly in confined spaces of coated particle scaffolds as thermal underfills with extraordinary thermal conductivity.

PubMed

Hong, Guo; Schutzius, Thomas M; Zimmermann, Severin; Burg, Brian R; Zürcher, Jonas; Brunschwiler, Thomas; Tagliabue, Giulia; Michel, Bruno; Poulikakos, Dimos

2015-01-14

In situ assembly of high thermal conductivity materials in severely confined spaces is an important problem bringing with it scientific challenges but also significant application relevance. Here we present a simple, affordable, and reproducible methodology for synthesizing such materials, composed of hierarchical diamond micro/nanoparticle scaffolds and an ethylenediamine coating. An important feature of the assembly process is the utilization of ethylenediamine as an immobilizing agent to secure the integrity of the microparticle scaffolds during and after each processing step. After other liquid components employed in the scaffolds assembly dry out, the immobilization agent solidifies forming a stable coated particle scaffold structure. Nanoparticles tend to concentrate in the shell and neck regions between adjacent microparticles. The interface between core and shell, along with the concentrated neck regions of nanoparticles, significantly enhance the thermal conductivity, making such materials an excellent candidate as thermal underfills in the electronics industry, where efficient heat removal is a major stumbling block toward increasing packing density. We show that the presented structures exhibit nearly 1 order of magnitude improvement in thermal conductivity, enhanced temperature uniformity, and reduced processing time compared to commercially available products for electronics cooling, which underpins their potential utility.

Simulation of Thin Film Equations on an Eye-Shaped Domain with Moving Boundary

NASA Astrophysics Data System (ADS)

Brosch, Joseph; Driscoll, Tobin; Braun, Richard

During a normal eye blink, the upper lid moves, and during the upstroke the lid paints a thin tear film over the exposed corneal and conjunctival surfaces. This thin tear film may be modeled by a nonlinear fourth-order PDE derived from lubrication theory. A major stumbling block in the numerical simulation of this model is to include both the geometry of the eye and the movement of the eyelid. Using a pair of orthogonal and conformal maps, we transform a computational box into a rough representation of a human eye where we proceed to simulate the thin tear film equations. Although we give up some realism, we gain spectrally accurate numerical methods on the computational box. We have applied this method to the heat equation on the blinking domain with both Dirichlet and no-flux boundary conditions, in each case demonstrating at least 10 digits of accuracy.. We are able to perform these simulations very quickly (generally in under a minute) using a desktop version of MATLAB. This project was supported by Grant 1022706 (R.J.B., T.A.D., J.K.B.) from the NSF.

Web-Based Organizational Tools for Professional Librarians

ERIC Educational Resources Information Center

Cooke, Nicole A.

2008-01-01

With the vastness of the Internet ever increasing, it is likely that busy, time-deprived librarians may not stumble upon valuable sites that may actually facilitate their organizational efforts and eventually save them time and energy, especially energy exerted prioritizing tasks and working in groups or other collaborative projects. This column…

Say: An Experiment in Learning.

ERIC Educational Resources Information Center

Stuart, Simon

This book is an account of one teacher's attempt to use English literature as a vehicle of self-discovery for both his adolescent students and himself. The first chapter, "Stumbling into New Techniques," relates some of the techniques used to encourage student writing and to stimulate an appreciation and understanding of poetry--to help…

Stumble into Grace

ERIC Educational Resources Information Center

Rogers, Jennifer

2015-01-01

Jennifer Rogers writes with apt and lyrical snippets from her perspective as a Montessori parent and from her long history as a primary guide. This short piece examines the word "grace" from multiple facets and serves as a meditation that uplifts and reminds us "that the life of a child is a gift."

Professor's Page: Is Understanding a Proficiency?

ERIC Educational Resources Information Center

Askew, Mike

2012-01-01

The everyday use of "proficient" carries connotations of having reached a level of expertise. One would not describe someone stumbling through a rendition of "Chopsticks" as a proficient piano player; but novice pianists work on musical proficiencies--practicing scales or playing a polka--in parallel. They do not put off…

The Stumbling Campaign for Free-Access Buildings

ERIC Educational Resources Information Center

Building Design and Construction, 1974

1974-01-01

Although a concerted effort has been made during the past 15 years to knock down the architectural barriers facing the handicapped, the existence of over 400,000 wheelchair handicapped and more than two million people wearing leg braces or with artificial legs makes it imperative that architectural designs produce completely barrier-free…

Intrapersonal Intelligence Strategies in the Developmental Writing Classroom

ERIC Educational Resources Information Center

Gleason, Mary Ellen

2011-01-01

While many of these intelligences can be incorporated into the higher education classroom, intrapersonal intelligence poses some intriguing opportunities in the developmental writing classroom. As an instructor of developmental writing, the author stumbled upon the value of students developing their self-knowledge as an aid in learning to write…

Anchoring Democracy: The Civic Imperative for Higher Education

ERIC Educational Resources Information Center

Guarasci, Richard

2018-01-01

American colleges and universities are facing a civic imperative. The nation is floundering, if not unwinding. Democracies are vulnerable social constructions. They flourish in eras of social consensus and economic prosperity, when citizens believe in the prospect of brighter futures. They stumble, if not decay, during times of harsh economic…

More than the Eye Can See

ERIC Educational Resources Information Center

Armstrong, Wendy

2011-01-01

The author was surfing the Internet and stumbled upon some amazing and surprisingly beautiful microscopic structures of living organisms. The colors and shapes of these individual forms of life were beautiful, textured, and intricate. In this article, the author describes how her eighth-grade students made tiles inspired by these microscopic…

3. View east, showing side (west) elevation of main block ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. View east, showing side (west) elevation of main block and ell. Granite ledge visible to near side of main block. - Conner Homestead, House, Epping Road (State Route 101), Exeter, Rockingham County, NH

Success by Failure

ERIC Educational Resources Information Center

Andrews, Benjamin D.

2017-01-01

By taking the step to talk openly about his failure, the author stumbled upon one of several important lessons that he learned from this experience. The author recognized that he did not have to pretend anymore. In this article, the author shares his story of developing a "growth mindset" to overcome his own failure and support his…

Great Globes

ERIC Educational Resources Information Center

Cronin, Jim

2004-01-01

While trying to explain to his seventh grade students why models are needed to study science, the author stumbled across this project idea. At the time, his class was just beginning to study geology and rocks and minerals. This unit starts by introducing the structure of the Earth so students had very little background knowledge. He wanted a quick…

American Colleges' Missteps Raise Questions about Overseas Partnerships

ERIC Educational Resources Information Center

Fischer, Karin

2012-01-01

Several stumbles by American colleges in setting up programs with foreign partners have called attention to problems inherent in making such arrangements. State University of New York Empire State College has allowed a university in Albania to deliver diplomas in its name. In North Dakota, state auditors issued a scathing review of dual-degree…

Beyond the Nation's Capital: Minority Students' Stumbling on the Tracks after Hobson

ERIC Educational Resources Information Center

McPherson, Ezella

2010-01-01

The U.S. District of Columbia's Federal Circuit Court decision in "Hobson v. Hanson" (1967) case eliminated racial discriminatory tracking practices in the nation's capitol's public schools. The court ruled that D.C. Public Schools' tracking violated African American and low income students' rights to equal opportunities to education…

The Learning Path of Patty Loew

ERIC Educational Resources Information Center

Rolo, Mark Anthony

2006-01-01

Three years ago, while researching archival photographs and records for a documentary on American Indian war veterans, Dr. Patty Loew stumbled upon a long forgotten film about her Ojibwe grandfather's World War I unit buried in the basement stacks of the Wisconsin Historical Society. Though it was a remarkable find, the truth is, for Loew, it was…

Three Years of the New Mexico Laptop Learning Initiative (NMLLI): Stumbling toward Innovation

ERIC Educational Resources Information Center

Rutledge, David; Duran, James; Carroll-Miranda, Joseph

2007-01-01

This article presents qualitative results of the first three years of the New Mexico Laptop Learning Initiative (NMLLI). Results suggest that teachers, students, and their communities support this initiative to improve student learning. Descriptive statistics were used during year two to further understand how the laptops were being used by…

Utilizing Interns in Facilities Management

ERIC Educational Resources Information Center

Judkins, Clarissa; Morris, John P.; Molocznik, Chuck

2011-01-01

Facilities management is rapidly changing and developing from a position an individual stumbles into--or work one's way up through--to a discipline and vocation all of its own. There is a need for a collaborative strategy among leaders in practice, education, and research to share knowledge and experience and to establish professional and ethical…

Slogging and Stumbling toward Social Justice in a Private Elementary School: The Complicated Case of St. Malachy

ERIC Educational Resources Information Center

Scanlan, Martin

2010-01-01

This case study examines St. Malachy, an urban Catholic elementary school primarily serving children traditionally marginalized by race, class, linguistic heritage, and disability. As a private school, St. Malachy serves the public good by recruiting and retaining such traditionally marginalized students. As empirical studies involving Catholic…

Growing Water Pearls

ERIC Educational Resources Information Center

Milner-Bolotin, Marina

2012-01-01

Science teachers can find lesson ideas almost anywhere. For example, during a recent visit to a local dollar store, the author stumbled upon a flower vase filled with water pearls, also known as water beads and jelly beans. She bought several of the bags (search the web to find numerous online sources), and soon began experimenting. Water pearls…

Missteps, Flaws and Morphings in Children's Musical Play: Snapshots from School Playgrounds

ERIC Educational Resources Information Center

Countryman, June

2014-01-01

This article, drawing upon fieldwork from a larger project investigating the nature of children's self-chosen musical play, explores instances of play that stumble and either morph into something else or are abandoned altogether. Four vignettes of musical play are described, documented during recess observations at several Canadian elementary…

Centralization and Decentralization in American Education Policy

ERIC Educational Resources Information Center

DeBoer, Jennifer

2012-01-01

This article examines the trend toward centralization in American education policy over the last century through a variety of lenses. The overall picture that emerges is one of a continuous tug-of-war, with national and local policymakers stumbling together toward incrementally more standardized and centralized policies. There is a center of power…

The Not-so-Random Drunkard's Walk

ERIC Educational Resources Information Center

Ehrhardt, George

2013-01-01

This dataset contains the results of a quasi-experiment, testing Karl Pearson's "drunkard's walk" analogy for an abstract random walk. Inspired by the alternate hypothesis that drunkards stumble to the side of their dominant hand, it includes data on intoxicated test subjects walking a 10' line. Variables include: the…

Performative Inquiry: Arresting the Villains in "Jack & the Beanstalk"

ERIC Educational Resources Information Center

Fels, Lynn M.

2008-01-01

From flower arranging to negotiating with a willful cow, an educator stumbles across the threshold into a performative space of learning that invites her to pay attention to what matters when a teacher encounters her students. Performative inquiry in the classroom brings to the curriculum a spirit and practice of inquiry, critical and creative…

Low-loss terahertz ribbon waveguides.

PubMed

Yeh, Cavour; Shimabukuro, Fred; Siegel, Peter H

2005-10-01

The submillimeter wave or terahertz (THz) band (1 mm-100 microm) is one of the last unexplored frontiers in the electromagnetic spectrum. A major stumbling block hampering instrument deployment in this frequency regime is the lack of a low-loss guiding structure equivalent to the optical fiber that is so prevalent at the visible wavelengths. The presence of strong inherent vibrational absorption bands in solids and the high skin-depth losses of conductors make the traditional microstripline circuits, conventional dielectric lines, or metallic waveguides, which are common at microwave frequencies, much too lossy to be used in the THz bands. Even the modern surface plasmon polariton waveguides are much too lossy for long-distance transmission in the THz bands. We describe a concept for overcoming this drawback and describe a new family of ultra-low-loss ribbon-based guide structures and matching components for propagating single-mode THz signals. For straight runs this ribbon-based waveguide can provide an attenuation constant that is more than 100 times less than that of a conventional dielectric or metallic waveguide. Problems dealing with efficient coupling of power into and out of the ribbon guide, achieving low-loss bends and branches, and forming THz circuit elements are discussed in detail. One notes that active circuit elements can be integrated directly onto the ribbon structure (when it is made with semiconductor material) and that the absence of metallic structures in the ribbon guide provides the possibility of high-power carrying capability. It thus appears that this ribbon-based dielectric waveguide and associated components can be used as fundamental building blocks for a new generation of ultra-high-speed electronic integrated circuits or THz interconnects.

Number sense in the transition from natural to rational numbers.

PubMed

Van Hoof, Jo; Verschaffel, Lieven; Van Dooren, Wim

2017-03-01

Rational numbers are of critical importance both in mathematics and in other fields of science. However, they form a stumbling block for learners. One widely known source of the difficulty learners have with rational numbers is the natural number bias, that is the tendency to (inappropriately) apply natural number properties in rational number tasks. Still, it has been shown that a good understanding of natural numbers is highly predictive for mathematics achievement in general, and for performance on rational number tasks in particular. In this study, we further investigated the relation between learners' natural and rational number knowledge, specifically in cases where a natural number bias may lead to errors. Participants were 140 sixth graders from six different primary schools. Participants completed a symbolic and a non-symbolic natural number comparison task, a number line estimation task, and a rational number sense test. Learners' natural number knowledge was found to be a good predictor of their rational number knowledge. However, after first controlling for learners' general mathematics achievement, their natural number knowledge only predicted the subaspect of operations with rational numbers. The results of this study suggest that the relation between learners' natural and rational number knowledge can largely be explained by their relation with learners' general mathematics achievement. © 2016 The British Psychological Society.

Current Challenges in Delivery and Cytosolic Translocation of Therapeutic RNAs

PubMed Central

Lucchino, Marco

2018-01-01

RNA interference (RNAi) is a fundamental cellular process for the posttranscriptional regulation of gene expression. RNAi can exogenously be modulated by small RNA oligonucleotides, such as microRNAs (miRNAs) and small interfering RNAs (siRNAs), or by antisense oligonucleotides. These small oligonucleotides provided the scientific community with powerful and versatile tools to turn off the expression of genes of interest, and hold out the promise of new therapeutic solutions against a wide range of gene-associated pathologies. However, unmodified nucleic acids are highly instable in biological systems, and their weak interaction with plasma proteins confers an unfavorable pharmacokinetics. In this review, we first provide an overview of the most efficient chemical strategies that, over the past 30 years, have been used to significantly improve the therapeutic potential of oligonucleotides. Oligonucleotides targeting and delivery technologies are then presented, including covalent conjugates between oligonucleotides and targeting ligand, and noncovalent association with lipid or polymer nanoparticles. Finally, we specifically focus on the endosomal escape step, which represents a major stumbling block for the effective use of oligonucleotides as therapeutic agents. The need for approaches to quantitatively measure endosomal escape and cytosolic arrival of biomolecules is discussed in the context of the development of efficient oligonucleotide targeting and delivery vectors. PMID:29883296

Model-based VQ for image data archival, retrieval and distribution

NASA Technical Reports Server (NTRS)

Manohar, Mareboyana; Tilton, James C.

1995-01-01

An ideal image compression technique for image data archival, retrieval and distribution would be one with the asymmetrical computational requirements of Vector Quantization (VQ), but without the complications arising from VQ codebooks. Codebook generation and maintenance are stumbling blocks which have limited the use of VQ as a practical image compression algorithm. Model-based VQ (MVQ), a variant of VQ described here, has the computational properties of VQ but does not require explicit codebooks. The codebooks are internally generated using mean removed error and Human Visual System (HVS) models. The error model assumed is the Laplacian distribution with mean, lambda-computed from a sample of the input image. A Laplacian distribution with mean, lambda, is generated with uniform random number generator. These random numbers are grouped into vectors. These vectors are further conditioned to make them perceptually meaningful by filtering the DCT coefficients from each vector. The DCT coefficients are filtered by multiplying by a weight matrix that is found to be optimal for human perception. The inverse DCT is performed to produce the conditioned vectors for the codebook. The only image dependent parameter used in the generation of codebook is the mean, lambda, that is included in the coded file to repeat the codebook generation process for decoding.

Decorating Graphene Oxide with Ionic Liquid Nanodroplets: An Approach Leading to Energy-Dense, High-Voltage Supercapacitors.

PubMed

She, Zimin; Ghosh, Debasis; Pope, Michael A

2017-10-24

A major stumbling block in the development of high energy density graphene-based supercapacitors has been maintaining high ion-accessible surface area combined with high electrode density. Herein, we develop an ionic liquid (IL)-surfactant microemulsion system that is found to facilitate the spontaneous adsorption of IL-filled micelles onto graphene oxide (GO). This adsorption distributes the IL over all available surface area and provides an aqueous formulation that can be slurry cast onto current collectors, leaving behind a dense nanocomposite film of GO/IL/surfactant. By removing the surfactant and reducing the GO through a low-temperature (360 °C) heat treatment, the IL plays a dual role of spacer and electrolyte. We study the effect of IL content and operating temperature on the performance, demonstrating a record high gravimetric capacitance (302 F/g at 1 A/g) for 80 wt % IL composites. At 60 wt % IL, combined high capacitance and bulk density (0.76 g/cm 3 ), yields one of the highest volumetric capacitances (218 F/cm 3 , at 1 A/g) ever reported for a high-voltage IL-based supercapacitor. While achieving promising rate performance and cycle-life, the approach also eliminates the long and costly electrolyte imbibition step of cell assembly as the electrolyte is cast directly with the electrode material.

Unconventional irreversible structural changes in a high-voltage Li–Mn-rich oxide for lithium-ion battery cathodes

DOE PAGES

Mohanty, Debasish; Sefat, Athena S.; Payzant, E. Andrew; ...

2015-02-19

Making all-electric vehicles (EVs) commonplace in transportation applications will require affordable high-power and high-energy-density lithium-ion batteries (LIBs). The quest for suitable cathode materials to meet this end has currently plateaued with the discovery of high-voltage (≥4.7 V vs. Li +), high capacity (~250 mAh/g) lithium–manganese-rich (LMR) layered composite oxides. In spite of the promise of LMR oxides in high-energy-density LIBs, an irreversible structural change has been identified in this work that is governed by the formation of a ‘permanent’ spin-glass type magnetically frustrated phase indicating a dominant AB 2O 4 (A = Li, B = Mn) type spinel after amore » short-term lithium deintercalation (charging) and intercalation (discharging) process. Furthermore, reduction of transition metal (Mn) ions from the 4+ state (pristine LMR) to 3+ (cycled LMR), which alters the intercalation redox chemistry and suggests the presence of ‘unfilled’ lithium vacancies and/or oxygen vacancies in the lattice after cycling, has presented a major stumbling block. Finally, these situations result in both loss of capacity and fading of the voltage profile, and these combined effects significantly reduce the high energy density over even short-term cycling.« less

At a glance: cellular biology for engineers.

PubMed

Khoshmanesh, K; Kouzani, A Z; Nahavandi, S; Baratchi, S; Kanwar, J R

2008-10-01

Engineering contributions have played an important role in the rise and evolution of cellular biology. Engineering technologies have helped biologists to explore the living organisms at cellular and molecular levels, and have created new opportunities to tackle the unsolved biological problems. There is now a growing demand to further expand the role of engineering in cellular biology research. For an engineer to play an effective role in cellular biology, the first essential step is to understand the cells and their components. However, the stumbling block of this step is to comprehend the information given in the cellular biology literature because it best suits the readers with a biological background. This paper aims to overcome this bottleneck by describing the human cell components as micro-plants that form cells as micro-bio-factories. This concept can accelerate the engineers' comprehension of the subject. In this paper, first the structure and function of different cell components are described. In addition, the engineering attempts to mimic various cell components through numerical modelling or physical implementation are highlighted. Next, the interaction of different cell components that facilitate complicated chemical processes, such as energy generation and protein synthesis, are described. These complex interactions are translated into simple flow diagrams, generally used by engineers to represent multi-component processes.

Integrated scientific data bases review on asulacrine and associated toxicity.

PubMed

Afzal, Attia; Sarfraz, Muhammad; Wu, Zimei; Wang, Guangji; Sun, Jianguo

2016-08-01

Asulacrine (ASL), a weakly basic and highly lipophilic drug was synthesized in 1980's in cancer research laboratory of Auckland by modifications to the acridine portion of amsacrine on 3-, 4- and 5-substitution patterns. In contrast to its precursor amsacrine (m-AMSA), ASL was effective not only against leukemia and Lewis lung tumor system but also a wide variety of solid tumor. Its metabolic pathway is not same to amsacrine hence different side effects, hepatotoxicity and excretion was observed. Asulacrine is under phase II clinical trials and has showed promising results but its toxicity especially phlebitis is stumbling block in its clinical implementation. This review is an effort to give a possible clue, based on scientifically proven results, to the researchers to solve the mystery of associated toxicity, phlebitis. Review covers the available literature on asulacrine and other acridine derivatives regarding pharmacology, pharmacokinetics, quantitative structure activity relationship and toxicology via electronic search using scientific databases like PubMed and others. To date, all abstracts and full-text articles were discussed and analyzed. The tabulated comparisons and circuitry mechanism of ASL are the added features of the review which give a complete understanding of hidden aspects of possible route cause of associated toxicity, the phlebitis. Copyright © 2016. Published by Elsevier Ireland Ltd.

Environmental Barrier Coatings for Ceramics and Ceramic Composites

NASA Technical Reports Server (NTRS)

Lee, Kang N.; Fox, Dennis; Eldridge, Jeffrey; Robinson, R. Craig; Bansal, Narottam

2004-01-01

One key factor that limits the performance of current gas turbine engines is the temperature capability of hot section structural components. Silicon-based ceramics, such as SiC/SiC composites and monolithic Si3N4, are leading candidates to replace superalloy hot section components in the next generation gas turbine engines due to their excellent high temperature properties. A major stumbling block to realizing Si-based ceramic hot section components is the recession of Si-based ceramics in combustion environments due to the volatilization of silica scale by water vapor. An external environmental barrier coating (EBC) is the most promising approach to preventing the recession. Current EBCs are based on silicon, mullite (3A12O3-2SiO2) and BSAS (barium strontium aluminum silicate with celsian structure). Volatility of BSAS, BSAS-silica chemical reaction, and low melting point of silicon limit the durability and temperature capability of current EBCs. Research is underway to develop EBCs with longer life and enhanced temperature capability. Understanding key issues affecting the performance of current EBCs is necessary for successful development of advanced EBCs. These issues include stress, chemical compatibility, adherence, and water vapor stability. Factors that affect stress are thermal expansion mismatch, phase stability, chemical stability, elastic modulus, etc. The current understanding on these issues will be discussed.

Modification of electronic properties of graphene by using low-energy K{sup +} ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jingul; Lee, Paengro; Ryu, Mintae

2016-05-02

Despite its superb electronic properties, the semi-metallic nature of graphene with no band gap (E{sub g}) at the Dirac point has been a stumbling block for its industrial application. We report an improved means of producing a tunable band gap over other schemes by doping low energy (10 eV) potassium ions (K{sup +}) on single layer graphene formed on 6H-SiC(0001) surface, where the noble Dirac nature of the π-band remains almost unaltered. The changes in the π-band induced by K{sup +} ions reveal that the band gap increases gradually with increasing dose (θ) of the ions up to E{sub g} = 0.65 eV atmore » θ = 1.10 monolayers, demonstrating the tunable character of the band gap. Our core level data for C 1s, Si 2p, and K 2p suggest that the K{sup +}-induced asymmetry in charge distribution among carbon atoms drives the opening of band gap, which is in sharp contrast with no band gap when neutral K atoms are adsorbed on graphene. This tunable K{sup +}-induced band gap in graphene illustrates its potential application in graphene-based nano-electronics.« less

Performance characterization of image and video analysis systems at Siemens Corporate Research

NASA Astrophysics Data System (ADS)

Ramesh, Visvanathan; Jolly, Marie-Pierre; Greiffenhagen, Michael

2000-06-01

There has been a significant increase in commercial products using imaging analysis techniques to solve real-world problems in diverse fields such as manufacturing, medical imaging, document analysis, transportation and public security, etc. This has been accelerated by various factors: more advanced algorithms, the availability of cheaper sensors, and faster processors. While algorithms continue to improve in performance, a major stumbling block in translating improvements in algorithms to faster deployment of image analysis systems is the lack of characterization of limits of algorithms and how they affect total system performance. The research community has realized the need for performance analysis and there have been significant efforts in the last few years to remedy the situation. Our efforts at SCR have been on statistical modeling and characterization of modules and systems. The emphasis is on both white-box and black box methodologies to evaluate and optimize vision systems. In the first part of this paper we review the literature on performance characterization and then provide an overview of the status of research in performance characterization of image and video understanding systems. The second part of the paper is on performance evaluation of medical image segmentation algorithms. Finally, we highlight some research issues in performance analysis in medical imaging systems.

The defining role of structure (including epitaxy) in the plausibility of homeopathy.

PubMed

Rao, Manju Lata; Roy, Rustum; Bell, Iris R; Hoover, Richard

2007-07-01

The key stumbling block to serious consideration of homeopathy is the presumed "implausibility" of biological activity for homeopathic medicines in which the source material is diluted past Avogadro's number of molecules. Such an argument relies heavily on the assumptions of elementary chemistry (and biochemistry), in which the material composition of a solution, (dilution factors and ligand-receptor interactions), is the essential consideration. In contrast, materials science focuses on the three-dimensional complex network structure of the condensed phase of water itself, rather than the original solute molecules. The nanoheterogenous structure of water can be determined by interactive phenomena such as epitaxy (the transmission of structural information from the surface of one material to another without the transfer of any matter), temperature-pressure processes during succussion, and formation of colloidal nanobubbles containing gaseous inclusions of oxygen, nitrogen, carbon dioxide, and possibly the remedy source material. Preliminary data obtained using Raman and Ultra-Violet-Visible (UV-VIS) spectroscopy illustrate the ability to distinguish two different homeopathic medicines (Nux vomica and Natrum muriaticum) from one another and to differentiate, within a given medicine, the 6c, 12c, and 30c potencies. Materials science concepts and experimental tools offer a new approach to contemporary science, for making significant advances in the basic science studies of homeopathic medicines.

Main-chain supramolecular block copolymers.

PubMed

Yang, Si Kyung; Ambade, Ashootosh V; Weck, Marcus

2011-01-01

Block copolymers are key building blocks for a variety of applications ranging from electronic devices to drug delivery. The material properties of block copolymers can be tuned and potentially improved by introducing noncovalent interactions in place of covalent linkages between polymeric blocks resulting in the formation of supramolecular block copolymers. Such materials combine the microphase separation behavior inherent to block copolymers with the responsiveness of supramolecular materials thereby affording dynamic and reversible materials. This tutorial review covers recent advances in main-chain supramolecular block copolymers and describes the design principles, synthetic approaches, advantages, and potential applications.

Hutchins's University of Utopia: Institutional Independence, Academic Freedom, and Radical Restructuring

ERIC Educational Resources Information Center

Hoff, Peter Sloat

2009-01-01

In a crisis-plagued world looking to higher education for knowledge, wisdom, and solutions, higher education itself is stumbling. Its transformational thinking has frozen up like an overstressed computer program; and we need, in effect, to "push the reset button." In 1953, the renowned and controversial president of the University of Chicago,…

Evidence for a "Wild" L2 Grammar: When PPs Rear Their Empty Heads.

ERIC Educational Resources Information Center

Klein, Elaine C.

1995-01-01

Reviews several studies which suggest that some second-language (L2) learners stumble into rogue or "wild" grammars on the road to the L2. L2 learners who have subcategorization knowledge of verbs for their prepositions often omit those same prepositions in relative clauses and questions requiring pied-piping or preposition stranding.…

Between History and Apocalypse: Stumbling

ERIC Educational Resources Information Center

Lalu, Premesh

2016-01-01

Apartheid rested on a division of the senses as much as it did on a reductive politics of racial subjection and its accompanying violence. As an instance of the division of the senses, it produced a condition of stasis in which history and a post-apartheid future were increasingly marked by a politico-religious discourse of apocalypse, and a moral…

International Business: Stumbling Through the Communications Corridor.

ERIC Educational Resources Information Center

Waltz, Loren E.

The increasing need for employees of U.S. businesses to speak the language of the customer is explored. It is shown that the need for foreign language skills in business far exceeds the supply and continues to increase. In the past, the detrimental impact of lack of language skills in U.S. business has been masked by the competitive advantage…

The Higher Education Research Archipelago

ERIC Educational Resources Information Center

Macfarlane, Bruce

2012-01-01

Ever since he stumbled into doing higher education research as a young academic in the 1980s, the author has been trying to understand it as a "field" of study. His career, as a former business lecturer, then an academic developer and now an associate professor for higher education working in an Education Faculty has given him opportunities to see…

Celluloid under Siege

ERIC Educational Resources Information Center

Doherty, Thomas

2008-01-01

From 1895, the traditional date for the birth of cinema as everybody knows it (that is, the projection of celluloid, in public space, for money--a racket first stumbled upon by Auguste and Louis Lumiere in the basement of the Grand Cafe in Paris), until now, the 35mm photographic image has been the preferred canvas for motion-picture art. Through…

The Attack of the Pod People

ERIC Educational Resources Information Center

Schneider, Robert

2006-01-01

In an article in the "Northern Star," a university student newspaper, reporter Lauren Stott began a lyrical note: "It's every student's dream: Wake up for school, stumble over to the computer, and download the day's class lectures ... then crawl back into bed--iPod in one hand, notebook in the other." The object of the student journalist's…

What Are We Learning about How We Learn

ERIC Educational Resources Information Center

Joyce, Bruce; Emily Calhoun

2016-01-01

Rather than merely dusting and polishing the old comfy stuff, these authors have spent 35 years trying to find out how people can learn to use new curriculums and ways of teaching. They have done some studies that would meet high standards of design, learned from peering at correlations, and stumbled on important things while teaching kids and…

Executive Transitions in Student Affairs: A Guide to Getting Started as the Vice President

ERIC Educational Resources Information Center

Carry, Ainsley, Ed.

2014-01-01

Transitions are a critical time for executives at all types of higher education institutions. Some vice presidents for student affairs sail through the transition period, while others stumble because they could not navigate the complexity of the new role. Vice presidents who appropriately match their leadership and management style to the new…

NOAA's world-class weather and climate prediction center opens at

Science.gov Websites

StumbleUpon Digg More Destinations NOAA's world-class weather and climate prediction center opens at currents and large-scale rain and snow storms. Billions of earth observations from around the world flow operations. Investing in this center is an investment in our human capital, serving as a world class facility

NOAA honors New York farmer for 84 years of service as volunteer weather

Science.gov Websites

Print Facebook Google StumbleUpon Digg More Destinations NOAA honors New York farmer for 84 years of Weather Service, Herbert Hoover occupied the White House. Since then the Bridgehampton, New York, farmer decades, the new 80-year service award will be named in his honor. Richard G. Hendrickson looks out over

Democratizing Academic Writing: A Revision of an Experience of Writing an Autoethnographic Dissertation in Color

ERIC Educational Resources Information Center

Polanco, Marcela

2013-01-01

In this paper, I revise my experience of writing an autoethnographic (Ellis, 2004) dissertation in the field of family therapy as a Colombian mestiza. I discuss how I grappled with my writing, and, in the process, stumbled into matters of democratizing texts. I problematize male-dominant academic standards, telling of the tensions when maneuvering…

Development of a gas chromatography-mass spectrometry technique to diagnose white snakeroot (Ageratina altissima) poisoning in a cow

USDA-ARS?s Scientific Manuscript database

An 8-year-old, crossbred beef cow was referred to the Indiana Animal Disease Diagnostic Laboratory at Purdue University for a complete necropsy in October 2009. The cow was the sixth to die in a 7-day period. Affected cows were reportedly stumbling and became weak, excitable, and recumbent. Histolog...

Stumbling at the First Step: Efficiency Implications of Poor Performance in the Foundational First Five Years

ERIC Educational Resources Information Center

Crouch, Luis; Merseth, Katherine A.

2017-01-01

This paper highlights patterns in school enrollment indicators that affect the efficiency and effectiveness of education systems in a set of low-income countries: those that have expanded access quickly in the last decade or two, but have not yet absorbed that expansion efficiently. Although the patterns in these indicators are observable in the…

Stumbling Through: How Joel Klein Reinvented the New York City Schools

ERIC Educational Resources Information Center

Viteritti, Joseph P.

2012-01-01

In this essay, the author reviews "Education Reform in New York City: Ambitious Change in the Nation's Most Complex School System," by Jennifer A. O'Day, Catherine S. Bitter, and Louis Gomez. The book under review explores a larger set of issues, and some time has passed. But many of the issues studied remain relevant and the consistent…

How Americans Can Help Children with Mental Illness, and Their Families, Help Themselves. Connect for Kids: Guidance for Grown-Ups.

ERIC Educational Resources Information Center

Louv, Richard

This article highlights the untended mental health needs of children across the United States. Citing troubling mental health statistics, the author suggests creating a community culture that does not stigmatize or ignore mental health problems, specifically by making prevention and treatment the rule. One of the potential stumbling blocks…

The Pathway from School to Work: Smoothing the Bumps

ERIC Educational Resources Information Center

Taylor, Alison

2007-01-01

The mid to late teen years are about as tumultuous as life can get. As such, it is not a surprise that so many young people seem to fumble their way through high school, maybe drop out altogether, and then stumble on their pathway to finding a good job. This problem was identified by the Organization for Economic Co-operation and Development…

In Search of a Good Critique

ERIC Educational Resources Information Center

Perlmutter, David D.

2013-01-01

Some job candidates seem to be doing well only to fall flat in one venue: They ace the teaching demo and the dinner meeting, but stumble during the research talk. Perhaps the candidate was disorganized, too strident, or just long-winded and boring. Whatever the cause, the outcome is a strong negative ding when it comes time to vote on the hire.…

Supplementing the One-Shot Session: Tools to Enhance Instruction beyond the Computer Lab

ERIC Educational Resources Information Center

Becker, Bernd W.

2012-01-01

It is always a pleasure to stumble upon a discussion about library topics as they become mainstream issues. Some of the satisfaction is simply validation, knowing that the work librarians are doing has implications that extend beyond the library's four walls. But usually the author is excited that the rest of the world finally "gets it." Last…

Level up Book Club

ERIC Educational Resources Information Center

LaGarde, Jennifer; Winner, Matthew C.

2012-01-01

Like all great ideas, Level Up Book Club grew out of a genuine need, the spontaneous firing of a few brain sparks, and the kind of luck that comes from being "in the right place at the right time." By mid-June 2011 the authors were already "bona fide" wonder twins--two educators who, although they'd never met, had stumbled upon each other through…

Stimulus Plan Aids Education: House Bill Could Provide $100 Billion to K-12 Schools

ERIC Educational Resources Information Center

Klein, Alyson

2009-01-01

Cash-strapped school districts could see an unprecedented $100 billion infusion of federal aid under a massive economic-stimulus package unveiled by House Democrats this week. The overall measure, put forth January 15 by the House Appropriations Committee, is aimed at providing a $825 billion jolt to the stumbling U.S. economy, and to help avert…

22. INTERIOR VIEW, BASEMENT UNDER NORTH ROOM OF MAIN BLOCK, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. INTERIOR VIEW, BASEMENT UNDER NORTH ROOM OF MAIN BLOCK, VIEW OF NORTHWEST WALL SHOWING CORBELING BASE OF FIRST FLOOR CHIMNEY BLOCK WITH STOVE-PIPE HOLE, AND MORTISE AND TENON FRAMING FOR HEARTH BED - Clifton Farm, Off Baker Road, Frederick, Frederick County, MD

Decoupling Semantic and Associative Information in False Memories: Explorations with Semantically Ambiguous and Unambiguous Critical Lures

ERIC Educational Resources Information Center

Hutchison, K.A.; Balota, D.A.

2005-01-01

Veridical and false memory were examined in lists that contained 12 words that all converged onto the same meaning of a critical nonpresented word (e.g., snooze, wake, bedroom, slumber..., for SLEEP) or lists that contained 6 words that converged onto one meaning and 6 words that converged onto a different meaning of a homograph (e.g., stumble,…

Maniac Talk - Dr. Eugenia Kalnay

NASA Image and Video Library

2015-03-31

Eugenia Kalnay Maniac Lecture, March 31, 2015 Dr. Eugenia Kalnay, Distinguished University Professor and the first woman to get a doctorate in Meteorology from MIT, presented a Maniac Talk entitled, "Sheer luck: How I stumbled my way through a fantastic scientific career." Eugenia shared her life and times at the University of Buenos Aires, MIT, NASA, NOAA and University of Maryland, infused with dreams from her mother.

The Evolution of Counterrevolutionary Doctrine in the U.S. Military. The Second Seminole; Philippine and Vietnam Wars. Did We Learn our Lessons

DTIC Science & Technology

1993-04-01

Management and Budget. Paperwork Reduction Project (0704-011). Washington. DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. .REPOR.DAT13. RPORT TYPE AND DATES...his support bas and will to fWgh Lasly, as pointed out, the Army stumbled onto the tactic of neutralizing the memy leadeship . Howevr, litnk qportance

2 Professors Rock Out Online to Study Fame--and Us

ERIC Educational Resources Information Center

Young, Jeffrey R.

2009-01-01

Most people who stumble across the YouTube video of the self-proclaimed rock star Gory Bateson singing to a scantily clad prostitute in Amsterdam's red-light district probably have no idea that the work is part of a research project--or that the man holding the guitar is a tenured professor. The video has attracted more than 12,000 views and won a…

13. Photocopy of photograph (original print in the private collection ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Photocopy of photograph (original print in the private collection of Mr. Orton Camp, Waterbury, Connecticut) ca. 1890, photographer unknown DEXTER'S DRUG STORE IN SOUTHWEST CORNER OF HOTCHKISS BLOCK ON EAST MAIN STREET - Hotchkiss Block (Irving Block), 11 East Main Street, Waterbury, New Haven County, CT

A large eddy simulation scheme for turbulent reacting flows

NASA Technical Reports Server (NTRS)

Gao, Feng

1993-01-01

The recent development of the dynamic subgrid-scale (SGS) model has provided a consistent method for generating localized turbulent mixing models and has opened up great possibilities for applying the large eddy simulation (LES) technique to real world problems. Given the fact that the direct numerical simulation (DNS) can not solve for engineering flow problems in the foreseeable future (Reynolds 1989), the LES is certainly an attractive alternative. It seems only natural to bring this new development in SGS modeling to bear on the reacting flows. The major stumbling block for introducing LES to reacting flow problems has been the proper modeling of the reaction source terms. Various models have been proposed, but none of them has a wide range of applicability. For example, some of the models in combustion have been based on the flamelet assumption which is only valid for relatively fast reactions. Some other models have neglected the effects of chemical reactions on the turbulent mixing time scale, which is certainly not valid for fast and non-isothermal reactions. The probability density function (PDF) method can be usefully employed to deal with the modeling of the reaction source terms. In order to fit into the framework of LES, a new PDF, the large eddy PDF (LEPDF), is introduced. This PDF provides an accurate representation for the filtered chemical source terms and can be readily calculated in the simulations. The details of this scheme are described.

Early Detection of Motor Dysfunction in the SOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis (ALS) Using Home Cage Running Wheels

PubMed Central

Bennett, Ellen J.; Mead, Richard J.; Azzouz, Mimoun; Shaw, Pamela J.; Grierson, Andrew J.

2014-01-01

The SOD1G93A mouse has been used since 1994 for preclinical testing in amyotrophic lateral sclerosis (ALS). Despite recent genetic advances in our understanding of ALS, transgenic mice expressing mutant SOD1 remain the best available, and most widely used, vertebrate model of the disease. We previously described an optimised and rapid approach for preclinical studies in the SOD1G93A mouse. Here we describe improvements to this approach using home cage running wheels to obtain daily measurements of motor function, with minimal intervention. We show that home cage running wheels detect reductions in motor function at a similar time to the rotarod test, and that the data obtained are less variable allowing the use of smaller groups of animals to obtain satisfactory results. This approach refines use of the SOD1G93A model, and reduces the number of animals undergoing procedures of substantial severity, two central principles of the 3Rs (replacement, reduction and refinement of animal use in research). The small group sizes and rapid timescales enable affordable large-scale therapeutic pre-screening in the SOD1G93A mouse, as well as rapid validation of published positive effects in a second laboratory, one of the major stumbling blocks in ALS preclinical therapy development. PMID:25268710

Multi-phase functionalization of titanium for enhanced photon absorption in the vis-NIR region.

PubMed

Thakur, Pooja; Tan, Bo; Venkatakrishnan, Krishnan

2015-10-19

Inadequate absorption of Near Infrared (NIR) photons by conventional silicon solar cells has been a major stumbling block towards the attainment of a high efficiency "full spectrum" solar cell. An effective enhancement in the absorption of such photons is desired as they account for a considerable portion of the tappable solar energy. In this work, we report a remarkable gain observed in the absorption of photons in the near infrared and visible region (400 nm-1000 nm) by a novel multi-phased oxide of titanium. Synthesised via a single step ultra-fast laser pulse interaction with pure titanium, characterisation studies have identified this oxide of titanium to be multi-phased and composed of Ti3O, (TiO.716)3.76 and TiO2 (rutile). Computed to have an average band gap value of 2.39 eV, this ultrafast laser induced multi-phased titanium oxide has especially exhibited steady absorption capability in the NIR range of 750-1000 nm, which to the best of our knowledge, was never reported before. The unique NIR absorption properties of the laser functionalised titanium coupled with the simplicity and versatility of the ultrafast laser interaction process involved thereby provides tremendous potential towards the photon sensitization of titanium and thereafter for the inception of a "full spectrum" solar device.

Functional molecular markers for crop improvement.

PubMed

Kage, Udaykumar; Kumar, Arun; Dhokane, Dhananjay; Karre, Shailesh; Kushalappa, Ajjamada C

2016-10-01

A tremendous decline in cultivable land and resources and a huge increase in food demand calls for immediate attention to crop improvement. Though molecular plant breeding serves as a viable solution and is considered as "foundation for twenty-first century crop improvement", a major stumbling block for crop improvement is the availability of a limited functional gene pool for cereal crops. Advancement in the next generation sequencing (NGS) technologies integrated with tools like metabolomics, proteomics and association mapping studies have facilitated the identification of candidate genes, their allelic variants and opened new avenues to accelerate crop improvement through development and use of functional molecular markers (FMMs). The FMMs are developed from the sequence polymorphisms present within functional gene(s) which are associated with phenotypic trait variations. Since FMMs obviate the problems associated with random DNA markers, these are considered as "the holy grail" of plant breeders who employ targeted marker assisted selections (MAS) for crop improvement. This review article attempts to consider the current resources and novel methods such as metabolomics, proteomics and association studies for the identification of candidate genes and their validation through virus-induced gene silencing (VIGS) for the development of FMMs. A number of examples where the FMMs have been developed and used for the improvement of cereal crops for agronomic, food quality, disease resistance and abiotic stress tolerance traits have been considered.

Against the integrative turn in bioethics: burdens of understanding.

PubMed

Savić, Lovro; Ivanković, Viktor

2018-06-01

The advocates of Integrative Bioethics have insisted that this recently emerging project aspires to become a new stage of bioethical development, surpassing both biomedically oriented bioethics and global bioethics. We claim in this paper that if the project wants to successfully replace the two existing paradigms, it at least needs to properly address and surmount the lack of common moral vocabulary problem. This problem points to a semantic incommensurability due to cross-language communication in moral terms. This paper proceeds as follows. In the first part, we provide an overview of Integrative Bioethics and its conceptual building blocks: mutlidisciplinarity, interdisciplinarity, and transdisciplinarity. In the second part, we disclose the problem of semantic incommensurability. The third part gives an overview of various positions on the understanding of interdisciplinarity and integration in interdisciplinary communication, and corresponding attempts at solving the lack of common moral vocabulary problem. Here we lean mostly on Holbrook's three theses regarding the character of interdisciplinary communication. Finally, in the fourth part, we discuss a particular bioethical case-that of euthanasia-to demonstrate the challenge semantic incommensurability poses to dialogues in Integrative Bioethics. We conclude that Integrative Bioethics does not offer a methodological toolset that would warrant optimism in its advocates' predictions of surpassing current modes of doing bioethics. Since Integrative Bioethics leaves controversial methodological questions unresolved on almost all counts and shows no attempts at overcoming the critical stumbling points, we argue for its rejection.

Determinants of High Titer in Recombinant Porcine Endogenous Retroviruses

PubMed Central

Harrison, Ian; Takeuchi, Yasuhiro; Bartosch, Birke; Stoye, Jonathan P.

2004-01-01

Porcine endogenous retroviruses (PERVs) pose a potential stumbling block for therapeutic xenotransplantation, with the greatest threat coming from viruses generated by recombination between members of the PERV subgroup A (PERV-A) and PERV-C families (PERV-A/C recombinants). PERV-A and PERV-B have been shown to infect human cells in culture, albeit with low titers. PERV-C has a more restricted host range and cannot infect human cells. A recombinant PERV-A/C virus (PERV-A14/220) contains the PERV-A sequence between the end of pol and the middle of the SU region in env. The remaining sequence is derived from PERV-C. PERV-A14/220 is approximately 500-fold more infectious than PERV-A. To determine the molecular basis for the increased infectivity of PERV-A14/220, we have made a series of vector constructs. The primary determinant for the enhanced replicative potential of the recombinant virus appeared to be the env gene. Using a series of chimeric env genes, we could identify two determinants of high infectivity; one was an isoleucine to valine substitution at position 140 between variable regions A and B, and the other lies within the proline rich region. Taken together, these results show that the novel juxtaposition of env gene sequences enhanced the infectivity of PERV-A14/220 for human cells, perhaps by stabilization of the envelope glycoprotein or increased receptor binding. PMID:15564495

Impact of yellow fever on the developing world.

PubMed

Tomori, O

1999-01-01

Yellow fever (YF) has remained a disease of public health importance since it was first described in the fifteenth century. At different periods in human history, YF has caused untold hardship and indescribable misery among populations in the Americas, Europe, and Africa. It brought economic disaster in its wake, constituting a stumbling block to development. Yellow fever is an arboviral infection with three epidemiological transmission cycles between monkeys, mosquitoes, and humans. It is an acute infectious disease characterized by sudden onset, with two phases of development separated by a short period of remission. The clinical spectrum of YF varies from a very mild, nonspecific, febrile illness to a fulminating, sometimes fatal disease with pathognomonic features. In severe cases, jaundice and bleeding diathesis with hepatorenal involvement are common. The fatality rate of severe YF is 50% or higher. Despite landmark achievements in the understanding of the epidemiology of YF and the availability of a safe, efficacious vaccine, YF remains a major public health problem in both Africa and South America, where annually the disease affects an estimated 200,000 persons, causing an estimated 30,000 deaths. Since the 1980s epidemics of YF in Africa have affected predominantly children under the age of 15 years. The failure to control YF arises from a misapplication of public health strategies and insufficient political commitment by governments in YF endemic areas, especially in Africa, to control the disease.

The role of culture in effective HIV/AIDS communication by theatre in South Africa.

PubMed

Uwah, Chijioke

2013-01-01

The need to effectively communicate HIV/AIDS messages in South Africa, given the high prevalence of the pandemic, cannot be overemphasised. Communication scholars have long emphasised the need to recognise adherence to cultural norms of target communities as catalyst for effective HIV/AIDS communication. Unfortunately this call has not been totally heeded by the designers of HIV/AIDS communication instruments. In the case of theatre, research has shown that in South Africa, theatre groups have gone into communities with pre-packaged plays without due cognisance of the cultural norms and beliefs of the target population. This research was conducted in KwaZulu-Natal (the province with the highest prevalence rate of HIV/AIDS infection in South Africa). Using a qualitative research methodology this paper investigated the inclusion/non-inclusion of the cultural norms of the target population in the design of the dramatic performance by the theatre group in its HIV/AIDS campaigns. The findings indicate that while the group did try to incorporate aspects of the cultural norms of the target population, it did so at a level that failed to effectively communicate the HIV/AIDS message to its audiences. This paper therefore seeks to show through empirical evidence that the non-inclusion of cultural norms and values of the target population has acted as a stumbling block in the effective communication of HIV/AIDS messages by theatre groups in the country.

Are computational models of any use to psychiatry?

PubMed

Huys, Quentin J M; Moutoussis, Michael; Williams, Jonathan

2011-08-01

Mathematically rigorous descriptions of key hypotheses and theories are becoming more common in neuroscience and are beginning to be applied to psychiatry. In this article two fictional characters, Dr. Strong and Mr. Micawber, debate the use of such computational models (CMs) in psychiatry. We present four fundamental challenges to the use of CMs in psychiatry: (a) the applicability of mathematical approaches to core concepts in psychiatry such as subjective experiences, conflict and suffering; (b) whether psychiatry is mature enough to allow informative modelling; (c) whether theoretical techniques are powerful enough to approach psychiatric problems; and (d) the issue of communicating clinical concepts to theoreticians and vice versa. We argue that CMs have yet to influence psychiatric practice, but that they help psychiatric research in two fundamental ways: (a) to build better theories integrating psychiatry with neuroscience; and (b) to enforce explicit, global and efficient testing of hypotheses through more powerful analytical methods. CMs allow the complexity of a hypothesis to be rigorously weighed against the complexity of the data. The paper concludes with a discussion of the path ahead. It points to stumbling blocks, like the poor communication between theoretical and medical communities. But it also identifies areas in which the contributions of CMs will likely be pivotal, like an understanding of social influences in psychiatry, and of the co-morbidity structure of psychiatric diseases. Copyright © 2011 Elsevier Ltd. All rights reserved.

Histone deacetylases in monocyte/macrophage development, activation and metabolism: refining HDAC targets for inflammatory and infectious diseases.

PubMed

Das Gupta, Kaustav; Shakespear, Melanie R; Iyer, Abishek; Fairlie, David P; Sweet, Matthew J

2016-01-01

Macrophages have central roles in danger detection, inflammation and host defense, and consequently, these cells are intimately linked to most disease processes. Major advances in our understanding of the development and function of macrophages have recently come to light. For example, it is now clear that tissue-resident macrophages can be derived from either blood monocytes or through local proliferation of phagocytes that are originally seeded during embryonic development. Metabolic state has also emerged as a major control point for macrophage activation phenotypes. Herein, we review recent literature linking the histone deacetylase (HDAC) family of enzymes to macrophage development and activation, particularly in relation to these recent developments. There has been considerable interest in potential therapeutic applications for small molecule inhibitors of HDACs (HDACi), not only for cancer, but also for inflammatory and infectious diseases. However, the enormous range of molecular and cellular processes that are controlled by different HDAC enzymes presents a potential stumbling block to clinical development. We therefore present examples of how classical HDACs control macrophage functions, roles of specific HDACs in these processes and approaches for selective targeting of drugs, such as HDACi, to macrophages. Development of selective inhibitors of macrophage-expressed HDACs and/or selective delivery of pan HDACi to macrophages may provide avenues for enhancing efficacy of HDACi in therapeutic applications, while limiting unwanted side effects.

Histone deacetylases in monocyte/macrophage development, activation and metabolism: refining HDAC targets for inflammatory and infectious diseases

PubMed Central

Das Gupta, Kaustav; Shakespear, Melanie R; Iyer, Abishek; Fairlie, David P; Sweet, Matthew J

2016-01-01

Macrophages have central roles in danger detection, inflammation and host defense, and consequently, these cells are intimately linked to most disease processes. Major advances in our understanding of the development and function of macrophages have recently come to light. For example, it is now clear that tissue-resident macrophages can be derived from either blood monocytes or through local proliferation of phagocytes that are originally seeded during embryonic development. Metabolic state has also emerged as a major control point for macrophage activation phenotypes. Herein, we review recent literature linking the histone deacetylase (HDAC) family of enzymes to macrophage development and activation, particularly in relation to these recent developments. There has been considerable interest in potential therapeutic applications for small molecule inhibitors of HDACs (HDACi), not only for cancer, but also for inflammatory and infectious diseases. However, the enormous range of molecular and cellular processes that are controlled by different HDAC enzymes presents a potential stumbling block to clinical development. We therefore present examples of how classical HDACs control macrophage functions, roles of specific HDACs in these processes and approaches for selective targeting of drugs, such as HDACi, to macrophages. Development of selective inhibitors of macrophage-expressed HDACs and/or selective delivery of pan HDACi to macrophages may provide avenues for enhancing efficacy of HDACi in therapeutic applications, while limiting unwanted side effects. PMID:26900475

A history of watershed research in experimental forests of the Interior Highlands

Treesearch

Daniel A. Marion; Donald Turton; Maria Schleidt

2014-01-01

The history of watershed research in the Interior Highlands can be divided into four periods: Initial Start and Stumble (1930s–1950s), Reestablishment and Renewal (1960–1980), Partnerships and Expansion (1980–1990), and New Scales and Paths (1990–present). While each of these periods was marked by different societal concerns and scientific questions, experimental...

Human relationships with wilderness: The fundamental definition of wilderness character

Treesearch

Alan E. Watson

2004-01-01

The science that has guided wilderness management thus far is not really very old. It couldn’t be. Wilderness legislation has guided U.S. federal agency managers since 1964. My own introduction to wilderness research was when I stumbled onto a series of debate articles by some of the few people engaged in early wilderness research during my freshman year of college in...

Discovering the flight autostabilizer of fruit flies by inducing aerial stumbles

PubMed Central

Ristroph, Leif; Bergou, Attila J.; Ristroph, Gunnar; Coumes, Katherine; Berman, Gordon J.; Guckenheimer, John; Wang, Z. Jane; Cohen, Itai

2010-01-01

Just as the Wright brothers implemented controls to achieve stable airplane flight, flying insects have evolved behavioral strategies that ensure recovery from flight disturbances. Pioneering studies performed on tethered and dissected insects demonstrate that the sensory, neurological, and musculoskeletal systems play important roles in flight control. Such studies, however, cannot produce an integrative model of insect flight stability because they do not incorporate the interaction of these systems with free-flight aerodynamics. We directly investigate control and stability through the application of torque impulses to freely flying fruit flies (Drosophila melanogaster) and measurement of their behavioral response. High-speed video and a new motion tracking method capture the aerial “stumble,” and we discover that flies respond to gentle disturbances by accurately returning to their original orientation. These insects take advantage of a stabilizing aerodynamic influence and active torque generation to recover their heading to within 2° in < 60 ms. To explain this recovery behavior, we form a feedback control model that includes the fly’s ability to sense body rotations, process this information, and actuate the wing motions that generate corrective aerodynamic torque. Thus, like early man-made aircraft and modern fighter jets, the fruit fly employs an automatic stabilization scheme that reacts to short time-scale disturbances. PMID:20194789

Discovering the flight autostabilizer of fruit flies by inducing aerial stumbles.

PubMed

Ristroph, Leif; Bergou, Attila J; Ristroph, Gunnar; Coumes, Katherine; Berman, Gordon J; Guckenheimer, John; Wang, Z Jane; Cohen, Itai

2010-03-16

Just as the Wright brothers implemented controls to achieve stable airplane flight, flying insects have evolved behavioral strategies that ensure recovery from flight disturbances. Pioneering studies performed on tethered and dissected insects demonstrate that the sensory, neurological, and musculoskeletal systems play important roles in flight control. Such studies, however, cannot produce an integrative model of insect flight stability because they do not incorporate the interaction of these systems with free-flight aerodynamics. We directly investigate control and stability through the application of torque impulses to freely flying fruit flies (Drosophila melanogaster) and measurement of their behavioral response. High-speed video and a new motion tracking method capture the aerial "stumble," and we discover that flies respond to gentle disturbances by accurately returning to their original orientation. These insects take advantage of a stabilizing aerodynamic influence and active torque generation to recover their heading to within 2 degrees in < 60 ms. To explain this recovery behavior, we form a feedback control model that includes the fly's ability to sense body rotations, process this information, and actuate the wing motions that generate corrective aerodynamic torque. Thus, like early man-made aircraft and modern fighter jets, the fruit fly employs an automatic stabilization scheme that reacts to short time-scale disturbances.

Visually guided gait modifications for stepping over an obstacle: a bio-inspired approach.

PubMed

Silva, Pedro; Matos, Vitor; Santos, Cristina P

2014-02-01

There is an increasing interest in conceiving robotic systems that are able to move and act in an unstructured and not predefined environment, for which autonomy and adaptability are crucial features. In nature, animals are autonomous biological systems, which often serve as bio-inspiration models, not only for their physical and mechanical properties, but also their control structures that enable adaptability and autonomy-for which learning is (at least) partially responsible. This work proposes a system which seeks to enable a quadruped robot to online learn to detect and to avoid stumbling on an obstacle in its path. The detection relies in a forward internal model that estimates the robot's perceptive information by exploring the locomotion repetitive nature. The system adapts the locomotion in order to place the robot optimally before attempting to step over the obstacle, avoiding any stumbling. Locomotion adaptation is achieved by changing control parameters of a central pattern generator (CPG)-based locomotion controller. The mechanism learns the necessary alterations to the stride length in order to adapt the locomotion by changing the required CPG parameter. Both learning tasks occur online and together define a sensorimotor map, which enables the robot to learn to step over the obstacle in its path. Simulation results show the feasibility of the proposed approach.

Fireplace detail, east wall, northeast secondfloor room, main block, showing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Fireplace detail, east wall, northeast second-floor room, main block, showing ghost of surround and mantle. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

Efficient Low Dissipative High Order Schemes for Multiscale MHD Flows

NASA Technical Reports Server (NTRS)

Sjoegreen, Bjoern; Yee, Helen C.; Mansour, Nagi (Technical Monitor)

2002-01-01

Accurate numerical simulations of complex multiscale compressible viscous flows, especially high speed turbulence combustion and acoustics, demand high order schemes with adaptive numerical dissipation controls. Standard high resolution shock-capturing methods are too dissipative to capture the small scales and/or long-time wave propagations without extreme grid refinements and small time steps. An integrated approach for the control of numerical dissipation in high order schemes for the compressible Euler and Navier-Stokes equations has been developed and verified by the authors and collaborators. These schemes are suitable for the problems in question. Basically, the scheme consists of sixth-order or higher non-dissipative spatial difference operators as the base scheme. To control the amount of numerical dissipation, multiresolution wavelets are used as sensors to adaptively limit the amount and to aid the selection and/or blending of the appropriate types of numerical dissipation to be used. Magnetohydrodynamics (MHD) waves play a key role in drag reduction in highly maneuverable high speed combat aircraft, in space weather forecasting, and in the understanding of the dynamics of the evolution of our solar system and the main sequence stars. Although there exist a few well-studied second and third-order high-resolution shock-capturing schemes for the MHD in the literature, these schemes are too diffusive and not practical for turbulence/combustion MHD flows. On the other hand, extension of higher than third-order high-resolution schemes to the MHD system of equations is not straightforward. Unlike the hydrodynamic equations, the inviscid MHD system is non-strictly hyperbolic with non-convex fluxes. The wave structures and shock types are different from their hydrodynamic counterparts. Many of the non-traditional hydrodynamic shocks are not fully understood. Consequently, reliable and highly accurate numerical schemes for multiscale MHD equations pose a great challenge to algorithm development. In addition, controlling the numerical error of the divergence free condition of the magnetic fields for high order methods has been a stumbling block. Lower order methods are not practical for the astrophysical problems in question. We propose to extend our hydrodynamics schemes to the MHD equations with several desired properties over commonly used MHD schemes.

A Native Intelligence Metric for Artificial Systems

DTIC Science & Technology

2002-08-01

an example to help clarify the GCEA. Say we are S and we stumble upon Stonehenge . We don’t wonder whether humans carried the stones (some...stones S encounters that may be exhibiting alignment with celestial bodies at certain seasonal times. S determines that the designer of Stonehenge had...matching of the stones with particular celestial events. The various celestial events and our prehistoric Stonehenge designer’s awareness of these events

Block-Parallel Data Analysis with DIY2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morozov, Dmitriy; Peterka, Tom

DIY2 is a programming model and runtime for block-parallel analytics on distributed-memory machines. Its main abstraction is block-structured data parallelism: data are decomposed into blocks; blocks are assigned to processing elements (processes or threads); computation is described as iterations over these blocks, and communication between blocks is defined by reusable patterns. By expressing computation in this general form, the DIY2 runtime is free to optimize the movement of blocks between slow and fast memories (disk and flash vs. DRAM) and to concurrently execute blocks residing in memory with multiple threads. This enables the same program to execute in-core, out-of-core, serial,more » parallel, single-threaded, multithreaded, or combinations thereof. This paper describes the implementation of the main features of the DIY2 programming model and optimizations to improve performance. DIY2 is evaluated on benchmark test cases to establish baseline performance for several common patterns and on larger complete analysis codes running on large-scale HPC machines.« less

The categorisation of swimming start performance with reference to force generation on the main block and footrest components of the Omega OSB11 start blocks.

PubMed

Slawson, Sian E; Conway, Paul P; Cossor, Jodi; Chakravorti, Nandini; West, Andrew A

2013-01-01

Work presented in this paper provides a methodology for categorising swimming start performance based on peak force production on the main block and footrest components of the Omega OSB11 starting block. A total of 46 elite British swimmers were tested, producing over 1000 start trials. Overwater cameras were synchronised to a specifically designed start block that allowed the measurement of force production via two sets of four, tri-axis, force transducers; one set in the main block and one in the footrest. Data were then analysed, segregating trials for gender. Each start was categorised, with respect to the peak force production in horizontal and vertical components, into one of nine categories. Three performance indicators, i.e. block time, take-off velocity and distance of entry, were used to assess whether differences in performance could be correlated with these categories. Results from these data suggest that swimmers generating higher than average peak forces were more likely to produce a better overall start performance than those who produced forces lower than the average, for this population of athletes.

Sales compensation governance: the last frontier of corporate reform.

PubMed

Gundy, Peter R; Gaeta, Elizabeth C

2004-01-01

The area of sales compensation has remained relatively untouched by recent pressures for compensation reform. This article highlights some of the ways that sales organizations stumble in managing their compensation programs, and why it takes more than a simple tactical fix to address these problems effectively. The authors describe a more structured governance framework that not only identifies and resolves key sales compensation issues, but ultimately safeguards the effectiveness and financial integrity of the sales organization itself.

West elevation, southwest firstfloor room, main block. This room is ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

West elevation, southwest first-floor room, main block. This room is believed to be the one referred to as the "Committee Room" in institutional records. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

The impact of different types of assistive devices on gait measures and safety in Huntington's disease.

PubMed

Kloos, Anne D; Kegelmeyer, Deborah A; White, Susan E; Kostyk, Sandra K

2012-01-01

Gait and balance impairments lead to frequent falls and injuries in individuals with Huntington's disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs.

The Impact of Different Types of Assistive Devices on Gait Measures and Safety in Huntington's Disease

PubMed Central

White, Susan E.; Kostyk, Sandra K.

2012-01-01

Background Gait and balance impairments lead to frequent falls and injuries in individuals with Huntington's disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. Methods Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. Results Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs. PMID:22363511

Joint geriatric and old-age psychiatric wards in the U.K., 1940s-early 1990s: a historical study.

PubMed

Hilton, Claire

2014-10-01

This study aims to investigate the history of joint geriatric-psychiatric units. For policy making and planning of high-quality clinical service models, clinical and social contexts need to be considered. Longitudinal, contextual information can be provided by historical analyses, including the successes and failures of earlier, similar services. Historical analyses complement clinical, randomised controlled studies and may contribute to ensuring optimum outcomes for future schemes. Standard historical methodology was used, including searching published sources and institutional and personal archives and conducting a 'witness seminar' and individual oral history interviews. Proposals to create joint units have existed since 1947. Most clinically successful units were led by enthusiastic, dedicated clinicians. Joint units had the potential to provide appropriate assessment and treatment for patients with multiple disorders and education for staff and students. Joint units never became widespread. Reasons for the limited success of joint geriatric-psychiatric units might have included personalities of individuals, administrative boundaries separating geriatrics and medicine, unequal numbers of geriatricians and old-age psychiatrists, varying professional ideologies about the meaning of 'integrated' services, lack of reciprocity for each other's inpatients and lack of government support. Identified stumbling blocks need to be considered when planning joint clinical schemes. If current research indicates benefits of integrated wards for patients and their families, there needs to be ways to ensure that personal factors and fashions of management or government re-prioritisation will not lead to their premature termination. Copyright © 2014 John Wiley & Sons, Ltd.

The role of culture in effective HIV/AIDS communication by theatre in South Africa

PubMed Central

Uwah, Chijioke

2014-01-01

The need to effectively communicate HIV/AIDS messages in South Africa, given the high prevalence of the pandemic, cannot be overemphasised. Communication scholars have long emphasised the need to recognise adherence to cultural norms of target communities as catalyst for effective HIV/AIDS communication. Unfortunately this call has not been totally heeded by the designers of HIV/AIDS communication instruments. In the case of theatre, research has shown that in South Africa, theatre groups have gone into communities with pre-packaged plays without due cognisance of the cultural norms and beliefs of the target population. This research was conducted in KwaZulu-Natal (the province with the highest prevalence rate of HIV/AIDS infection in South Africa). Using a qualitative research methodology this paper investigated the inclusion/non-inclusion of the cultural norms of the target population in the design of the dramatic performance by the theatre group in its HIV/AIDS campaigns. The findings indicate that while the group did try to incorporate aspects of the cultural norms of the target population, it did so at a level that failed to effectively communicate the HIV/AIDS message to its audiences. This paper therefore seeks to show through empirical evidence that the non-inclusion of cultural norms and values of the target population has acted as a stumbling block in the effective communication of HIV/AIDS messages by theatre groups in the country. PMID:24697309

Collaborating to reduce costs in invasive cardiology: the Partners Healthcare experience. Partners Healthcare Invasive Cardiology Team.

PubMed

Lee, T H

1995-11-01

As part of the closely watched marriage between Brigham and Women's Hospital and Massachusetts General Hospital, the invasive cardiology team--cardiologists and other staff from the two organizations--began with monthly meetings; its mission is to reduce costs of cardiology services while maintaining or improving patient satisfaction and outcomes. Joint purchasing efforts have led to substantial price reductions for some supplies, such as pacemakers and balloon angioplasty. However, concern over quality drove cardiologists to choose newer, more expensive models of other supplies, such as implantible cardioverter-defibrillators. Also, the team is studying the actual costs savings that can be achieved by shifting patients undergoing cardiac catheterization to the outpatient setting. In addition, cardiologists recognized an opportunity to decrease length of stay and increase quality by removing the arterial sheath for uncomplicated percutaneous transluminal coronary angioplasty patients on the same day the procedure is performed. Each hospital is developing strategies for this change in procedure. In addition to these improvement efforts, the team is encouraging optimal use of contrast agents and increasing overall efficiency of laboratories. Team members are also sharing guidelines and critical pathways and developing strategies for evaluating new technologies. The team has had little difficulty in achieving a collegial atmosphere and consensus around clinical issues and products once clinicians are face-to-face. Announcing bimonthly meetings may overcome meeting scheduling difficulties. The other major stumbling block has been the lack of detailed cost information.

Patching. Restitching business portfolios in dynamic markets.

PubMed

Eisenhardt, K M; Brown, S L

1999-01-01

In turbulent markets, businesses and opportunities are constantly falling out of alignment. New technologies and emerging markets create fresh opportunities. Converging markets produce more. And of course, some markets fade. In this landscape of continuous flux, it's more important to build corporate-level strategic processes that enable dynamic repositioning than it is to build any particular defensible position. That's why smart corporate strategists use patching, a process of mapping and remapping business units to create a shifting mix of highly focused, tightly aligned businesses that can respond to changing market opportunities. Patching is not just another name for reorganizing; patchers have a distinctive mindset. Traditional managers see structure as stable; patching managers believe structure is inherently temporary. Traditional managers set corporate strategy first, but patching managers keep the organization focused on the right set of business opportunities and let strategy emerge from individual businesses. Although the focus of patching is flexibility, the process itself follows a pattern. Patching changes are usually small in scale and made frequently. Patching should be done quickly; the emphasis is on getting the patch about right and fixing problems later. Patches should have a test drive before they're formalized but then be tightly scripted after they've been announced. And patching won't work without the right infrastructure: modular business units, fine-grained and complete unit-level metrics, and companywide compensation parity. The authors illustrate how patching works and point out some common stumbling blocks.

Building corporate character. Interview by Nan Stone.

PubMed

Hiatt, A

1992-01-01

Stride Rite is a good company by any definition: Keds, Sperry Top-Siders, and Stride Rite children's shoes are consumer favorites for their fit, quality, and comfort. Wall Street analysts praise the company's outstanding financial performance. Innovative programs such as the first corporate child-care center and public service scholarships support Stride Rite's reputation as one of the most responsible employers and corporate citizens in the United States. Behind Stride Rite's good performance are the building blocks of corporate character: a legacy of quality and service and a leader committed to keeping that legacy lively. When Stride Rite shipped its first children's shoes in 1919, they came with the company's commitment "to produce an honest quality product in an honest way and deliver it as promised." For Arnold Hiatt, that commitment has been the driving force behind the company's evolution from manufacturing into marketing and product development as well as the guiding principle in its relations with consumers, dealers, suppliers, and employees. But Stride Rite's corporate character is also a reflection of Hiatt himself. In his early 20s, Hiatt fled a management training program "designed to make carnivores" out of its new employees and bought Blue Star Shoes, a small manufacturing company that had gone into Chapter 11. Through experience and "stumbling around," he built Blue Star's sales to $5 million-and got a practical education in management, markets, and human nature that has proved equally useful in running Stride Rite.

Immune evasion in cancer: Mechanistic basis and therapeutic strategies.

PubMed

Vinay, Dass S; Ryan, Elizabeth P; Pawelec, Graham; Talib, Wamidh H; Stagg, John; Elkord, Eyad; Lichtor, Terry; Decker, William K; Whelan, Richard L; Kumara, H M C Shantha; Signori, Emanuela; Honoki, Kanya; Georgakilas, Alexandros G; Amin, Amr; Helferich, William G; Boosani, Chandra S; Guha, Gunjan; Ciriolo, Maria Rosa; Chen, Sophie; Mohammed, Sulma I; Azmi, Asfar S; Keith, W Nicol; Bilsland, Alan; Bhakta, Dipita; Halicka, Dorota; Fujii, Hiromasa; Aquilano, Katia; Ashraf, S Salman; Nowsheen, Somaira; Yang, Xujuan; Choi, Beom K; Kwon, Byoung S

2015-12-01

Cancer immune evasion is a major stumbling block in designing effective anticancer therapeutic strategies. Although considerable progress has been made in understanding how cancers evade destructive immunity, measures to counteract tumor escape have not kept pace. There are a number of factors that contribute to tumor persistence despite having a normal host immune system. Immune editing is one of the key aspects why tumors evade surveillance causing the tumors to lie dormant in patients for years through "equilibrium" and "senescence" before re-emerging. In addition, tumors exploit several immunological processes such as targeting the regulatory T cell function or their secretions, antigen presentation, modifying the production of immune suppressive mediators, tolerance and immune deviation. Besides these, tumor heterogeneity and metastasis also play a critical role in tumor growth. A number of potential targets like promoting Th1, NK cell, γδ T cell responses, inhibiting Treg functionality, induction of IL-12, use of drugs including phytochemicals have been designed to counter tumor progression with much success. Some natural agents and phytochemicals merit further study. For example, use of certain key polysaccharide components from mushrooms and plants have shown to possess therapeutic impact on tumor-imposed genetic instability, anti-growth signaling, replicative immortality, dysregulated metabolism etc. In this review, we will discuss the advances made toward understanding the basis of cancer immune evasion and summarize the efficacy of various therapeutic measures and targets that have been developed or are being investigated to enhance tumor rejection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spin relaxation of radicals in cryptochrome and its role in avian magnetoreception

DOE Office of Scientific and Technical Information (OSTI.GOV)

Worster, Susannah; Kattnig, Daniel R.; Hore, P. J., E-mail: peter.hore@chem.ox.ac.uk

2016-07-21

Long-lived spin coherence and rotationally ordered radical pairs have previously been identified as key requirements for the radical pair mechanism of the avian magnetic compass sense. Both criteria are hard to meet in a biological environment, where thermal motion of the radicals creates dynamic disorder and drives efficient spin relaxation. This has long been cited as a major stumbling block of the radical pair hypothesis. Here we combine Redfield relaxation theory with analytical solutions to a rotational diffusion equation to assess the impact of restricted rotational motion of the radicals on the operation of the compass. The effects of suchmore » motions are first investigated generally in small, model systems and are then critically examined in the magnetically sensitive flavin-tryptophan radical pair that is formed photochemically in the proposed magnetoreceptor protein, cryptochrome. We conclude that relaxation is slowest when rotational motion of the radicals within the protein is fast and highly constrained; that in a regime of slow relaxation, the motional averaging of hyperfine interactions has the potential to improve the sensitivity of the compass; and that consideration of motional effects can significantly alter the design criteria for an optimal compass. In addition, we demonstrate that motion of the flavin radical is likely to be compatible with its role as a component of a functioning radical-pair compass, whereas the motion of the tryptophan radical is less ideal, unless it is particularly fast.« less

[Stumbling-blocks: initiating a psychosomatic pain clinic].

PubMed

Heger, S; Lieberz, K

2000-12-01

Despite psychosocial factors playing an important role in the course of chronic pain disorder, there is a noticeable imbalance between demand and availability of psychosomatic care for these patients. This led us to establish a psychosomatic pain clinic within the framework of our outpatient clinic at the Department of Psychosomatic Medicine and Psychotherapy at the Central Institute of Mental Health, Mannheim, Germany. A recent study aimed at the evaluation of sociodemographic variables, state of chronification, symptom load and psychiatric comorbidity. Additionally we wanted to determine whether existing conditions at our hospital can be considered suitable for those patients. During the clinic's first year we assessed 40 consecutive patients based on a psychosomatic interview as well as a set of psychometric questionnaires (BDI, STAI, SCL-90-R). To detect differences between pain patients and psychotherapy inpatients, we compared the two groups in terms of sociodemographic variables and symptom load. Most pain patients were in advanced states of chronification, showing extensive psychiatric comorbidity, particularly anxiety and depressive syndromes. Drug addiction was found more infrequently. Use of the before mentioned questionnaires prevented us from underestimating existing anxiety syndromes. Pain patients differed substantially from psychotherapy inpatients in terms of age, education, family status and symptom load. Our examination routine effectively demonstrated the special needs of chronic pain patients. As there is significant demand for psychosomatic intervention in those patients, earlier referral appears highly desirable. As pain patients differ also greatly from the remaining hospital population, specialized therapeutic concepts must be developed.

How Does the Democratic Party of Japan Affect Security Policy? High-Profile Stumbles and Quiet Progress

DTIC Science & Technology

2012-07-01

collision between a Chinese fishing trawler and a Japan Coast Guard ship off the Senkaku Islands in 2010. Ø The nuclear reactor disasters that followed... triggered by that day’s natural disasters , which is not considered security policy for the purposes of this report. 21 in Afghanistan. In contrast...presidentialization” of political leadership and a greater emphasis on two-party competition triggered politicization of a wide range of policy issues, including

The International Criminal Court’s First Years: Stumbling Toward Justice

DTIC Science & Technology

2012-03-20

person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control... current U.S. policy of engagement with the ICC and Assembly of States Parties (ASP) to the RS provides the best opportunity for continued development...credibility and relevance of the court was sorely tested. The current U.S. policy of engagement with the ICC and Assembly of States Parties (ASP) to

Brazil’s National Defense Strategy: Prospects for the Twenty-First Century

DTIC Science & Technology

1993-06-01

also see Everardo Backheuser, Curso de Geopolitica Geral e do Brasil, (Rio de Janeiro: Biblioteca do ’Ex~rcito, 1952). 21 chance of dislocation of the...34, Latin American Weekly Report, 14 January 1993, WR-93-02, 14. 46 virtually irresistible, and the reality is that Brazil is stumbling with its national...cut off Brazil’s primary source of oil. Brazilian arms manufactures, such as EMBRAER, ENGESA, and AVIBRAS, went deep into debt, teetering on virtual

[Case Report: young woman with reduced state of consciousness - rescue team stumble across curious cause].

PubMed

Czaplik, Michael; Brokmann, Jörg; Rossaint, Rolf

2010-01-01

Causes for reduced states of consciousness are diverse; it is often impossible to directly reveal the underlying agents. The following case report describes a young healthy patient who showed a temporary unconsciousness that first appeared seemingly without reason. Accidentally we hit a very uncommon cause for the prevailing carbon monoxide intoxication and were able to prevent further impairment of health status of both patient and environment. (c) Georg Thieme Verlag Stuttgart New York.

A fast direct method for block triangular Toeplitz-like with tri-diagonal block systems from time-fractional partial differential equations

NASA Astrophysics Data System (ADS)

Ke, Rihuan; Ng, Michael K.; Sun, Hai-Wei

2015-12-01

In this paper, we study the block lower triangular Toeplitz-like with tri-diagonal blocks system which arises from the time-fractional partial differential equation. Existing fast numerical solver (e.g., fast approximate inversion method) cannot handle such linear system as the main diagonal blocks are different. The main contribution of this paper is to propose a fast direct method for solving this linear system, and to illustrate that the proposed method is much faster than the classical block forward substitution method for solving this linear system. Our idea is based on the divide-and-conquer strategy and together with the fast Fourier transforms for calculating Toeplitz matrix-vector multiplication. The complexity needs O (MNlog2 ⁡ M) arithmetic operations, where M is the number of blocks (the number of time steps) in the system and N is the size (number of spatial grid points) of each block. Numerical examples from the finite difference discretization of time-fractional partial differential equations are also given to demonstrate the efficiency of the proposed method.

Wearable Smart System for Visually Impaired People

PubMed Central

2018-01-01

In this paper, we present a wearable smart system to help visually impaired persons (VIPs) walk by themselves through the streets, navigate in public places, and seek assistance. The main components of the system are a microcontroller board, various sensors, cellular communication and GPS modules, and a solar panel. The system employs a set of sensors to track the path and alert the user of obstacles in front of them. The user is alerted by a sound emitted through a buzzer and by vibrations on the wrist, which is helpful when the user has hearing loss or is in a noisy environment. In addition, the system alerts people in the surroundings when the user stumbles over or requires assistance, and the alert, along with the system location, is sent as a phone message to registered mobile phones of family members and caregivers. In addition, the registered phones can be used to retrieve the system location whenever required and activate real-time tracking of the VIP. We tested the system prototype and verified its functionality and effectiveness. The proposed system has more features than other similar systems. We expect it to be a useful tool to improve the quality of life of VIPs. PMID:29533970

Wearable Smart System for Visually Impaired People.

PubMed

Ramadhan, Ali Jasim

2018-03-13

In this paper, we present a wearable smart system to help visually impaired persons (VIPs) walk by themselves through the streets, navigate in public places, and seek assistance. The main components of the system are a microcontroller board, various sensors, cellular communication and GPS modules, and a solar panel. The system employs a set of sensors to track the path and alert the user of obstacles in front of them. The user is alerted by a sound emitted through a buzzer and by vibrations on the wrist, which is helpful when the user has hearing loss or is in a noisy environment. In addition, the system alerts people in the surroundings when the user stumbles over or requires assistance, and the alert, along with the system location, is sent as a phone message to registered mobile phones of family members and caregivers. In addition, the registered phones can be used to retrieve the system location whenever required and activate real-time tracking of the VIP. We tested the system prototype and verified its functionality and effectiveness. The proposed system has more features than other similar systems. We expect it to be a useful tool to improve the quality of life of VIPs.

Comparison of nonmicroprocessor knee mechanism versus C-Leg on Prosthesis Evaluation Questionnaire, stumbles, falls, walking tests, stair descent, and knee preference.

PubMed

Kahle, Jason T; Highsmith, M Jason; Hubbard, Sandra L

2008-01-01

This study compared subjects' performance with a nonmicroprocessor knee mechanism (NMKM) versus a C-Leg on nine clinically repeatable evaluative measures. We recorded data on subjects' performance while they used an accommodated NMKM and, following a 90-day accommodation period, the C-Leg in a convenience sample of 19 transfemoral (TF) amputees (mean age 51 +/- 19) from an outpatient prosthetic clinic. We found that use of the C-Leg improved function in all outcomes: (1) Prosthesis Evaluation Questionnaire scores increased 20% (p = 0.007), (2) stumbles decreased 59% (p = 0.006), (3) falls decreased 64% (p = 0.03), (4) 75 m self-selected walking speed on even terrain improved 15% (p = 0.03), (5) 75 m fastest possible walking speed (FPWS) on even terrain improved 12% (p = 0.005), (6) 38 m FPWS on uneven terrain improved 21% (p < 0.001), (7) 6 m FPWS on even terrain improved 17% (p = 0.001), (8) Montreal Rehabilitation Performance Profile Performance Composite Scores for stair descent increased for 12 subjects, and (9) the C-Leg was preferred over the NMKM by 14 subjects. Four limited community ambulators (Medicare Functional Classification Level [MFCL] K2) increased their ambulatory functional level to unlimited community ambulation (MFCL K3). Objective evaluative clinical measures are vital for justifying the medical necessity of knee mechanisms for TF amputees. Use of the C-Leg improves performance and quality of life and can increase MFCL and community ambulation level.

Lattice enclosure, cellar passage, main block, looking south. Functioning with ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Lattice enclosure, cellar passage, main block, looking south. Functioning with vents opened through the masonry in the east and west walls, this partition provided a secure and aerated storage area for foodstuffs used in the nearby kitchen. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

Assessing cow-calf welfare. Part 2: Risk factors for beef cow health and behavior and stockperson handling.

PubMed

Simon, G E; Hoar, B R; Tucker, C B

2016-08-01

Epidemiological studies can be used to identify risk factors for livestock welfare concerns but have not been conducted in the cow-calf sector for this purpose. The objectives of this study were to investigate the relationships of 1) herd-level management, facilities, and producer perspectives with cattle health and behavior and stockperson handling and 2) stockperson handling on cattle behavior at the individual cow level. Cow ( = 3,065) health and behavior and stockperson handling during a routine procedure (e.g., pregnancy checks) were observed on 30 California ranches. Management and producer perspectives were evaluated using an interview, and handling facility features were recorded at the chute. After predictors were screened for univariable associations, multivariable models were built for cattle health (i.e., thin body condition, lameness, abrasions, hairless patches, swelling, blind eyes, and dirtiness) and behavior (i.e., balking, vocalizing, stumbling and falling in the chute and while exiting the restraint, and running out of the restraint) and stockperson handling (i.e., electric prod use, moving aid use, tail twisting, and mis-catching cattle). When producers empathized more toward an animal's pain experience, there was a lower risk of swelling (odds ratio [OR] = 0.7) but a higher risk of lameness (OR = 1.3), which may indicate a lack of awareness of the latter. Training stockpersons using the Beef Quality Assurance program had a protective effect on cow cleanliness and mis-catching in the restraint (OR = 0.2 and OR = 0.5, respectively). Hydraulic chutes increased the risk of vocalizations (OR = 2.7), possibly because these systems can apply greater pressure to the sides of the animal than manual restraints. When a moving aid was used to move an individual cow, it increased the risk of her balking, but when hands, in particular, were used, the risk of balking decreased across the herd (OR = 34.1 and OR = 0.3, respectively). Likewise, individual cows were at a greater risk of balking, vocalizing, stumbling and falling in the chute, and stumbling and running at exit when they were touched with an electric prod (OR = 11.0, OR = 3.3, OR = 1.9, OR = 2.3, OR = 1.8, and OR = 1.7, respectively). Although the implications of using moving aids are unclear, reducing the use of electric prods could improve cattle handling. In conclusion, cattle handling was influenced by a number of facility and stockperson factors: personnel training, facility design, and electric prod use are key areas for future improvements.

Development of Test Article Building Block (TABB) for deployable platform systems

NASA Technical Reports Server (NTRS)

Greenberg, H. S.; Barbour, R. T.

1984-01-01

The concept of a Test Article Building Block (TABB) is described. The TABB is a ground test article that is representative of a future building block that can be used to construct LEO and GEO deployable space platforms for communications and scientific payloads. This building block contains a main housing within which the entire structure, utilities, and deployment/retraction mechanism are stowed during launch. The end adapter secures the foregoing components to the housing during launch. The main housing and adapter provide the necessary building-block-to-building-block attachments for automatically deployable platforms. Removal from the shuttle cargo bay can be accomplished with the remote manipulator system (RMS) and/or the handling and positioning aid (HAPA). In this concept, all the electrical connections are in place prior to launch with automatic latches for payload attachment provided on either the end adapters or housings. The housings also can contain orbiter docking ports for payload installation and maintenance.

Elastic and Inelastic Collisions of a Ball with a Wood Block

ERIC Educational Resources Information Center

Cross, Rod

2017-01-01

In a recent article in this journal, Shakur described an interesting problem where a bullet of mass "m" strikes a block of wood of mass "M" and projects the block upward. The same problem was considered earlier by Cowley et al. and others. The main question of interest is whether the block rises to a greater height if it is…

Relevance of the electronic computer to hospital medical records*

PubMed Central

Mitchell, J. H.

1969-01-01

During the past 30 years an “information explosion” has completely changed patterns of illness. Unit files of individual patients have become so large that they are increasingly difficult both to store physically and to assimilate mentally. We have reached a communications barriers which poses a major threat to the efficient practice of clinical medicine. At the same time a new kind of machine, the electronic digital computer, which was invented only 26 years ago, has already come to dominate large areas of military, scientific, commercial, and industrial activity. Its supremacy rests on its ability to perform any data procedure automatically and incredibly quickly. Computers are being employed in clinical medicine in hospitals for various purposes. They can act as arithmetic calculators, they can process and analyse output from recording devices, and they can make possible the automation of various machine systems. However, in the field of case records their role is much less well defined, for here the organization of data as a preliminary to computer input is the real stumbling-block. Data banks of retrospective selected clinical information have been in operation in some centres for a number of years. Attempts are now being made to design computerized “total information systems” to replace conventional paper records, and the possibility of automated diagnosis is being seriously discussed. In my view, however, the medical profession is in danger of being dazzled by optimistic claims about the usefulness of computers in case record processing. The solution to the present problems of record storage and handling is very simple, and does not involve computerization. PMID:4898564

A computational framework for modeling targets as complex adaptive systems

NASA Astrophysics Data System (ADS)

Santos, Eugene; Santos, Eunice E.; Korah, John; Murugappan, Vairavan; Subramanian, Suresh

2017-05-01

Modeling large military targets is a challenge as they can be complex systems encompassing myriad combinations of human, technological, and social elements that interact, leading to complex behaviors. Moreover, such targets have multiple components and structures, extending across multiple spatial and temporal scales, and are in a state of change, either in response to events in the environment or changes within the system. Complex adaptive system (CAS) theory can help in capturing the dynamism, interactions, and more importantly various emergent behaviors, displayed by the targets. However, a key stumbling block is incorporating information from various intelligence, surveillance and reconnaissance (ISR) sources, while dealing with the inherent uncertainty, incompleteness and time criticality of real world information. To overcome these challenges, we present a probabilistic reasoning network based framework called complex adaptive Bayesian Knowledge Base (caBKB). caBKB is a rigorous, overarching and axiomatic framework that models two key processes, namely information aggregation and information composition. While information aggregation deals with the union, merger and concatenation of information and takes into account issues such as source reliability and information inconsistencies, information composition focuses on combining information components where such components may have well defined operations. Since caBKBs can explicitly model the relationships between information pieces at various scales, it provides unique capabilities such as the ability to de-aggregate and de-compose information for detailed analysis. Using a scenario from the Network Centric Operations (NCO) domain, we will describe how our framework can be used for modeling targets with a focus on methodologies for quantifying NCO performance metrics.

Will Regulatory and Financial Considerations Dampen Innovation in the Clinical Microbiology Laboratory?

PubMed

Gilligan, Peter H; Miller, Melissa B

2016-02-02

Over a million prosthetic joints are placed in patients in the United States annually. Of those that fail, 25% will be due to infection, with an estimated cost approaching 1 billion dollars. Despite the clinical and economic importance of these infections, the techniques for their detection are relatively insensitive. An innovative method for detecting these infections by using blood culture bottles (BCB) to culture specimens of periprosthetic tissue (PPT) was described in a recent article [T. N. Peel, et al., mBio 7(1):e01776-15, 2016, doi:10.1128/mBio.01776-15]. There are two potential stumbling blocks to the widespread implementation of this innovation. First, the FDA judges such an application of BCB as an "off-label use" and as such, a laboratory-developed test (LDT). LDTs are coming under greater scrutiny by the FDA and may require extensive, costly validation studies in laboratories that adopt this methodology. Second, the Center for Medicare and Medicaid Services has established a Hospital Acquired Condition Reduction Act under which institutions performing in the lowest quartile forfeit 1% of their Medicare reimbursement. Hospital-acquired infections are an important component of this quality metric. Although prosthetic joint infection (PJI) rates are not currently a hospital quality metric, given their cost and increasing frequency, it is reasonable to expect that they may become one. Will those with financial oversight allow an innovative technique that will require an expensive validation and may put the institution at risk for loss of CMS reimbursement? Copyright © 2016 Gilligan and Miller.

A UBK-space Visualization Tool for the Magnetosphere

NASA Astrophysics Data System (ADS)

Mohan, M.; Sheldon, R. B.

2001-12-01

One of the stumbling blocks to understanding particle transport in the magnetosphere has been the difficulty to follow, track and model the motion of ions through the realistic magnetic and electric fields of the Earth. Under the weak assumption that the first two invariants remain conserved, Whipple [1978] found a coordinate transformation that makes all charged particles travel on straight lines in UBK-space. The transform permits the quantitative calculation of conservative phase space transport for all particles with energies less than ~100 MeV, especially ring current energies (Sheldon and Gaffey [1993]). Furthermore Sheldon and Eastman [1997] showed how this transform extended the validity of diffusion models to realistic magnetospheres over the entire energy range. However, widespread usage of this transform has been limited by its non-intuitive UBK coordinates. We present a Virtual Reality Meta Language (VRML) interface to the calculation of UBK transform demonstrating its usefulness in describing both static features of the magnetosphere, such as the plasmapause, and dynamic features, such as ring current injection and loss. The core software is written in C for speed, whereas the interface is constructed in Perl and Javascript. The code is freely available, and intended for portability and modularity. R.B. Sheldon and T. Eastman ``Particle Transport in the Magnetosphere: A New Diffusion Model", GRL, 24(7), 811-814, 1997. Whipple, Jr, E. C. ``(U,B,K) coordinates: A natural system for studying magnetospheric convection". JGR, 83, 4318-4326, 1978. Sheldon, R. B. and J. D. Gaffey, Jr. ``Particle tracing in the magnetosphere: New algorithms and results." GRL, 20, 767-770, 1993.

An exploration of the factors that contribute to learning satisfaction of first-year anatomy and physiology students.

PubMed

Eagleton, Saramarie

2015-09-01

Lecturers have reverted to using a "blended" approach when teaching anatomy and physiology. Student responses as to how this contributes to their learning satisfaction were investigated using a self-administered questionnaire. The questionnaire consisted of closed- and open-ended questions that were based on three determinants of learning satisfaction: perceived course learnability, learning community support, and perceived learning effectiveness. Regarding course learnability, students responded positively on questions regarding the relevance of the subject for their future careers. However, students identified a number of distractions that prevented them from paying full attention to their studies. As far as learning community support was concerned, respondents indicated that they were more comfortable asking a peer for support if they were unsure of concepts than approaching the lecturing staff. Most of the students study in their second language, and this was identified as a stumbling block for success. There was a difference in opinion among students regarding the use of technology for teaching and learning of anatomy and physiology. From students' perceptions regarding learning effectiveness, it became clear that students' expectations of anatomy and physiology were unrealistic; they did not expect the module to be so comprehensive. Many of the students were also "grade oriented" rather than "learning oriented" as they indicated that they were more concerned about results than "owning" the content of the module. Asking students to evaluate aspects of the teaching and learning process have provided valuable information to improve future offerings of anatomy and physiology. Copyright © 2015 The American Physiological Society.

A questionnaire survey on diseases and problems affecting sheep and goats in communal farming regions of the Eastern Cape province, South Africa.

PubMed

Bath, Gareth F; Penrith, Mary-Louise; Leask, Rhoda

2016-08-31

A questionnaire of 15 questions was completed by four categories of respondents with the aim of establishing the experience and opinions of these groups on the constraints including animal health problems for communal, small-scale sheep and goat farming in the Eastern Cape province of South Africa. The questionnaires were completed independently and categories were representative of the areas investigated. Analysis of responses was done by means, ranges, votes and clusters of responses. Comparisons between the responses of the four categories were made to identify similarities or contrasts. The results revealed that of non-veterinary concerns, stock theft was the major problem for these farms. Nutrition was a further major constraint. A third area of significant concern was the provision or availability of facilities like fences, water troughs, dips and sheds. Lack of marketing and business skills were also seen as important deficiencies to be rectified so as to promote profitable farming. Of the most important veterinary problems identified, the provision, availability, cost and care of drugs and vaccines were seen as major stumbling blocks to effective disease control, as well as lack of access to veterinary services. The most important diseases that constrain small-ruminant livestock farming in the farming systems investigated were sheep scab and other ectoparasites, heart water, enterotoxaemia, internal parasites and bluetongue. A lack of knowledge in key areas of small-stock farming was revealed and should be rectified by an effective training and support programme to improve the contribution of small-ruminant farming to livelihoods in these communities.

Development of Prediction Model and Experimental Validation in Predicting the Curcumin Content of Turmeric (Curcuma longa L.).

PubMed

Akbar, Abdul; Kuanar, Ananya; Joshi, Raj K; Sandeep, I S; Mohanty, Sujata; Naik, Pradeep K; Mishra, Antaryami; Nayak, Sanghamitra

2016-01-01

The drug yielding potential of turmeric ( Curcuma longa L.) is largely due to the presence of phyto-constituent 'curcumin.' Curcumin has been found to possess a myriad of therapeutic activities ranging from anti-inflammatory to neuroprotective. Lack of requisite high curcumin containing genotypes and variation in the curcumin content of turmeric at different agro climatic regions are the major stumbling blocks in commercial production of turmeric. Curcumin content of turmeric is greatly influenced by environmental factors. Hence, a prediction model based on artificial neural network (ANN) was developed to map genome environment interaction basing on curcumin content, soli and climatic factors from different agroclimatic regions for prediction of maximum curcumin content at various sites to facilitate the selection of suitable region for commercial cultivation of turmeric. The ANN model was developed and tested using a data set of 119 generated by collecting samples from 8 different agroclimatic regions of Odisha. The curcumin content from these samples was measured that varied from 7.2% to 0.4%. The ANN model was trained with 11 parameters of soil and climatic factors as input and curcumin content as output. The results showed that feed-forward ANN model with 8 nodes (MLFN-8) was the most suitable one with R 2 value of 0.91. Sensitivity analysis revealed that minimum relative humidity, altitude, soil nitrogen content and soil pH had greater effect on curcumin content. This ANN model has shown proven efficiency for predicting and optimizing the curcumin content at a specific site.

What depressive symptoms are associated with the use of care services? Results from the Netherlands Mental Health Survey and Incidence Study (NEMESIS).

PubMed

ten Have, Margreet; de Graaf, Ron; Vollebergh, Wilma; Beekman, Aartjan

2004-06-01

Depression is generally regarded as a serious, incapacitating illness. Although effective treatment strategies are available, timely recognition remains a stumbling block. We investigated the rates of health service uptake among depressed people and the specific depressive symptoms associated with service use, after adjustment for other illness characteristics and sociodemographic variables. In a representative sample (n=7076) of the Dutch adult population, we identified 1572 subjects with lifetime major or minor depression, using the Composite International Diagnostic Interview. The majority (73%) of subjects with depression had sought specialised mental health care, or to a lesser extent primary care. As expected, those with more severe (vegetative), complex (anxiety-comorbid) or dangerous symptoms (suicidal ideation) were more likely to be treated in the specialised mental health sector. However, subjects with comorbid substance use dependence were less likely to receive care, especially primary care, and those with more education were more likely to receive specialised care, even after adjustment for illness characteristics. The use of lifetime measures of depression and service use may have introduced slight recall bias, but it made the assessments less vulnerable to selection bias for chronic cases and to misclassification of subjects with some lifetime treatment experience. Although care for people with depression is readily accessible in the Netherlands, people with less education and people with comorbid substance use dependence remain unnecessarily out of reach of the care services. Primary care services need to be strengthened to enable the broad-scale application of stepped-care strategies. Copyright 2003 Elsevier B.V.

Fidelity Failures in Brief Strategic Family Therapy for Adolescent Drug Abuse: A Clinical Analysis.

PubMed

Lebensohn-Chialvo, Florencia; Rohrbaugh, Michael J; Hasler, Brant P

2018-04-30

As evidence-based family treatments for adolescent substance use and conduct problems gain traction, cutting edge research moves beyond randomized efficacy trials to address questions such as how these treatments work and how best to disseminate them to community settings. A key factor in effective dissemination is treatment fidelity, which refers to implementing an intervention in a manner consistent with an established manual. While most fidelity research is quantitative, this study offers a qualitative clinical analysis of fidelity failures in a large, multisite effectiveness trial of Brief Strategic Family Therapy (BSFT) for adolescent drug abuse, where BSFT developers trained community therapists to administer this intervention in their own agencies. Using case notes and video recordings of therapy sessions, an independent expert panel first rated 103 cases on quantitative fidelity scales grounded in the BSFT manual and the broader structural-strategic framework that informs BSFT intervention. Because fidelity was generally low, the panel reviewed all cases qualitatively to identify emergent types or categories of fidelity failure. Ten categories of failures emerged, characterized by therapist omissions (e.g., failure to engage key family members, failure to think in threes) and commissions (e.g., off-model, nonsystemic formulations/interventions). Of these, "failure to think in threes" appeared basic and particularly problematic, reflecting the central place of this idea in structural theory and therapy. Although subject to possible bias, our observations highlight likely stumbling blocks in exporting a complex family treatment like BSFT to community settings. These findings also underscore the importance of treatment fidelity in family therapy research. © 2018 Family Process Institute.

Spatial heterogeneity in the Mediterranean Biodiversity Hotspot affects barcoding accuracy of its freshwater fishes.

PubMed

Geiger, M F; Herder, F; Monaghan, M T; Almada, V; Barbieri, R; Bariche, M; Berrebi, P; Bohlen, J; Casal-Lopez, M; Delmastro, G B; Denys, G P J; Dettai, A; Doadrio, I; Kalogianni, E; Kärst, H; Kottelat, M; Kovačić, M; Laporte, M; Lorenzoni, M; Marčić, Z; Özuluğ, M; Perdices, A; Perea, S; Persat, H; Porcelotti, S; Puzzi, C; Robalo, J; Šanda, R; Schneider, M; Šlechtová, V; Stoumboudi, M; Walter, S; Freyhof, J

2014-11-01

Incomplete knowledge of biodiversity remains a stumbling block for conservation planning and even occurs within globally important Biodiversity Hotspots (BH). Although technical advances have boosted the power of molecular biodiversity assessments, the link between DNA sequences and species and the analytics to discriminate entities remain crucial. Here, we present an analysis of the first DNA barcode library for the freshwater fish fauna of the Mediterranean BH (526 spp.), with virtually complete species coverage (498 spp., 98% extant species). In order to build an identification system supporting conservation, we compared species determination by taxonomists to multiple clustering analyses of DNA barcodes for 3165 specimens. The congruence of barcode clusters with morphological determination was strongly dependent on the method of cluster delineation, but was highest with the general mixed Yule-coalescent (GMYC) model-based approach (83% of all species recovered as GMYC entity). Overall, genetic morphological discontinuities suggest the existence of up to 64 previously unrecognized candidate species. We found reduced identification accuracy when using the entire DNA-barcode database, compared with analyses on databases for individual river catchments. This scale effect has important implications for barcoding assessments and suggests that fairly simple identification pipelines provide sufficient resolution in local applications. We calculated Evolutionarily Distinct and Globally Endangered scores in order to identify candidate species for conservation priority and argue that the evolutionary content of barcode data can be used to detect priority species for future IUCN assessments. We show that large-scale barcoding inventories of complex biotas are feasible and contribute directly to the evaluation of conservation priorities. © 2014 John Wiley & Sons Ltd.

The influence of medium conductivity on cells exposed to nsPEF

NASA Astrophysics Data System (ADS)

Moen, Erick K.; Ibey, Bennett L.; Roth, Caleb C.; Barnes, Ronald A.; Beier, Hope T.; Armani, Andrea M.

2017-02-01

Nanosecond pulsed electric fields (nsPEF) have proven useful for transporting cargo across cell membranes and selectively activating cellular pathways. The chemistry and biophysics governing this cellular response, however, are complex and not well understood. Recent studies have shown that the conductivity of the solution cells are exposed in could play a significant role in plasma membrane permeabilization and, thus, the overall cellular response. Unfortunately, the means of detecting this membrane perturbation has traditionally been limited to analyzing one possible consequence of the exposure - diffusion of molecules across the membrane. This method has led to contradictory results with respect to the relationship between permeabilization and conductivity. Diffusion experiments also suffer from "saturation conditions" making multi-pulse experiments difficult. As a result, this method has been identified as a key stumbling block to understanding the effects of nsPEF exposure. To overcome these limitations, we recently developed a nonlinear optical imaging technique based on second harmonic generation (SHG) that allows us to identify nanoporation in live cells during the pulse in a wide array of conditions. As a result, we are able to explore and fully test whether lower conductivity extracellular solutions could induce more efficient nanoporation. This hypothesis is based on membrane charging and the relative difference between the extracellular solution and the cytoplasm. The experiments also allow us to test the noise floor of our methodology against the effects of ion leakage. The results emphasize that the electric field, not ionic phenomenon, are the driving force behind nsPEF-induced membrane nanoporation.

Causation's nuclear future: applying proportional liability to the Price-Anderson Act.

PubMed

O'Connell, William D

2014-11-01

For more than a quarter century, public discourse has pushed the nuclear-power industry in the direction of heavier regulation and greater scrutiny, effectively halting construction of new reactors. By focusing on contemporary fear of significant accidents, such discourse begs the question of what the nation's court system would actually do should a major nuclear incident cause radiation-induced cancers. Congress's attempt to answer that question is the Price-Anderson Act, a broad statute addressing claims by the victims of a major nuclear accident. Lower courts interpreting the Act have repeatedly encountered a major stumbling block: it declares that judges must apply the antediluvian preponderance-of-the-evidence logic of state tort law, even though radiation science insists that the causes of radiation-induced cancers are more complex. After a major nuclear accident, the Act's paradoxically outdated rules for adjudicating "causation" would make post-incident compensation unworkable. This Note urges that nuclear-power-plant liability should not turn on eighteenth-century tort law. Drawing on modern scientific conclusions regarding the invariably "statistical" nature of cancer, this Note suggests a unitary federal standard for the Price-Anderson Act--that a defendant be deemed to have "caused" a plaintiff's injury in direct proportion to the increased risk of harm the defendant has imposed. This "proportional liability" rule would not only fairly evaluate the costs borne by injured plaintiffs and protect a reawakening nuclear industry from the prospect of bank-breaking litigation, but would prove workable with only minor changes to the Price-Anderson Act's standards of "injury" and "fault."

Chinese workers and labor conditions from state industry to globalized factories: how to stop the race to the bottom.

PubMed

Thorborg, Marina

2006-09-01

This article discusses administrative obstacles in China that hinder the full integration of the rural population into the mainstream of development during a period of rapid industrialization. The Chinese household registration only for urban residents with its golden contents of cradle-to-grave security has become a formidable stumbling block that perpetuates the status of rural migrants as second-class citizens in their own country. Rural migrant workers are excluded from certain types of jobs and are not eligible for many benefits that urbanites have, such as health, education, and unemployment protection. These workers must also pay a number of fees and work for lower minimum wages than the local residents. With a precarious legal existence in urban areas, they are easy prey to unscrupulous officials and employers. Because they are not allowed to form independent trade unions, their best option is to vote with their feet and leave the firms with the worst conditions; this is exactly what they did from 2004. Given this situation, the debate on Corporate Social Responsibility (CSR) took a new turn with not only nongovernmental organizations (NGOs) pushing it but with a wider range of employers and, of late, Chinese officials promoting their version of CSR. In the campaign to promote minimum labor standards, the norms set down in the Social Accountability 8000 were included in the CSR, recognizing the right to free collective bargaining and free trade unions but were excluded in the Chinese version even though the World Trade Organization (WTO) agreements recognized these rights.

Development of Prediction Model and Experimental Validation in Predicting the Curcumin Content of Turmeric (Curcuma longa L.)

PubMed Central

Akbar, Abdul; Kuanar, Ananya; Joshi, Raj K.; Sandeep, I. S.; Mohanty, Sujata; Naik, Pradeep K.; Mishra, Antaryami; Nayak, Sanghamitra

2016-01-01

The drug yielding potential of turmeric (Curcuma longa L.) is largely due to the presence of phyto-constituent ‘curcumin.’ Curcumin has been found to possess a myriad of therapeutic activities ranging from anti-inflammatory to neuroprotective. Lack of requisite high curcumin containing genotypes and variation in the curcumin content of turmeric at different agro climatic regions are the major stumbling blocks in commercial production of turmeric. Curcumin content of turmeric is greatly influenced by environmental factors. Hence, a prediction model based on artificial neural network (ANN) was developed to map genome environment interaction basing on curcumin content, soli and climatic factors from different agroclimatic regions for prediction of maximum curcumin content at various sites to facilitate the selection of suitable region for commercial cultivation of turmeric. The ANN model was developed and tested using a data set of 119 generated by collecting samples from 8 different agroclimatic regions of Odisha. The curcumin content from these samples was measured that varied from 7.2% to 0.4%. The ANN model was trained with 11 parameters of soil and climatic factors as input and curcumin content as output. The results showed that feed-forward ANN model with 8 nodes (MLFN-8) was the most suitable one with R2 value of 0.91. Sensitivity analysis revealed that minimum relative humidity, altitude, soil nitrogen content and soil pH had greater effect on curcumin content. This ANN model has shown proven efficiency for predicting and optimizing the curcumin content at a specific site. PMID:27766103

The Generic Mapping Tools 6: Classic versus Modern Mode

NASA Astrophysics Data System (ADS)

Wessel, P.; Uieda, L.; Luis, J. M. F.; Scharroo, R.; Smith, W. H. F.; Wobbe, F.

2017-12-01

The Generic Mapping Tools (GMT; gmt.soest.hawaii.edu) is a 25-year old, mature open-source software package for the analysis and display of geoscience data (e.g., interpolate, filter, manipulate, project and plot temporal and spatial data). The GMT "toolbox" includes about 80 core and 40 supplemental modules sharing a common set of command options, file structures, and documentation. GMT5, when released in 2013, introduced an application programming interface (API) to allow programmatic access to GMT from other computing environments. Since then, we have released a GMT/MATLAB toolbox, an experimental GMT/Julia package, and will soon introduce a GMT/Python module. In developing these extensions, we wanted to simplify the GMT learning curve but quickly realized the main stumbling blocks to GMT command-line mastery would be ported to the external environments unless we introduced major changes. With thousands of GMT scripts already in use by scientists around the world, we were acutely aware of the need for backwards compatibility. Our solution, to be released as GMT 6, was to add a modern run mode that complements the classic mode offered so far. Modern mode completely eliminates the top three obstacles for new (and not so new) GMT users: (1) The responsibility to properly stack PostScript layers manually (i.e., the -O -K dance), (2) the responsibility of handling output redirection of PostScript (create versus append), and (3) the need to provide commands with repeated information about regions (-R) and projections (-J). Thus, modern mode results in shorter, simpler scripts with fewer pitfalls, without interfering with classic scripts. Our implementation adds five new commands that begin and end a modern session, simplify figure management, automate the conversion of PostScript to more suitable formats, automate region detection, and offer a new automated subplot environment for multi-panel illustrations. Here, we highlight the GMT modern mode and the simplifications it offers, both for command-line use and in external environments. GMT 6 is in beta mode but accessible from our repository. Numerous improvements have been added in addition to modern mode; we expect a formal release in early 2018. Publication partially supported by FCT project UID/GEO/50019/2013 - Instituto D. Luiz.

Evaluation of the Effect of Water Vapor On the Performance of NASA's NMRO Catalysts for Carbon Monoxide Oxidation

NASA Technical Reports Server (NTRS)

Akyurtlu, Ates; Akyurtlu, Jale F.; Ammons, Vaughnery; Battle, Taikelia; Gay, Amy; Bray, Kyle; Washington, Boe; Schryer, David (Technical Monitor); Jordan, Jeff (Technical Monitor)

2002-01-01

The Noble Metal Reducible Oxide (NMRO) catalysts for the low temperature oxidation of carbon monoxide were developed by NASA for the reoxidation of carbon monoxide which forms by the dissociation of carbon dioxide during the operation of sealed carbon dioxide lasers. The NMRO catalyst, which consists of a noble metal in conjunction with a reducible metal oxide, was evaluated under conditions that will be encountered in a CO2 laser operation, namely temperatures in the range 298 to 373 K and no significant reaction gas components other than CO, CO2 and O2. The NMRO catalysts may have significant potential for spin-off applications such as the prevention of carbon monoxide build-up in closed spaces as in space vehicle cabins or submarines, and the elimination of the cold start-up problem of automobile exhaust catalysts. The most significant difference in the conditions of these possible future applications is the high moisture content of the gases to be processed. Lack of understanding of the effects of water vapor and high temperature on catalyst activity and operation for extended periods are currently the main stumbling blocks for the transfer of this NASA technology to be used for commercial purposes. In the original proposal the following objectives were stated: To obtain experimental data on the adsorption, desorption and reaction characteristics of CO and CO2 the catalysts under high moisture conditions; to collect evidence on the presence of carbonate and hydroxyl surface species and their involvement in the CO oxidation mechanism; and to model the reaction system using a Monte-Carlo simulation to gain insight on the various steps involved. After the work has commenced the NASA technical monitor Mr. David Scheyer informed us that there was increased interest in the possible use of the NMRO catalysts as automobile exhaust catalysts and therefore NASA wanted to know whether the catalysts can operate at high temperatures as well as with high moisture gases. At that meeting it was decided that investigation of the high temperature performance of the NMRO catalysts should be given priority and replace the Monte-Carlo simulation objective. As a result, the modified objectives of the investigation were taken as the investigation of the high-temperature activity of the NMRO catalysts, and the effect of water vapor on the performance of these catalysts.

Observing atmospheric blocking with GPS radio occultation - one decade of measurements

NASA Astrophysics Data System (ADS)

Brunner, Lukas; Steiner, Andrea

2017-04-01

Atmospheric blocking has received a lot of attention in recent years due to its impact on mid-latitude circulation and subsequently on weather extremes such as cold and warm spells. So far blocking studies have been based mainly on re-analysis data or model output. However, it has been shown that blocking frequency exhibits considerable inter-model spread in current climate models. Here we use one decade (2006 to 2016) of satellite-based observations from GPS radio occultation (RO) to analyze blocking in RO data building on work by Brunner et al. (2016). Daily fields on a 2.5°×2.5° longitude-latitude grid are calculated by applying an adequate gridding strategy to the RO measurements. For blocking detection we use a standard blocking detection algorithm based on 500 hPa geopotential height (GPH) gradients. We investigate vertically resolved atmospheric variables such as GPH, temperature, and water vapor before, during, and after blocking events to increase process understanding. Moreover, utilizing the coverage of the RO data set, we investigate global blocking frequencies. The main blocking regions in the northern and southern hemisphere are identified and the (vertical) atmospheric structure linked to blocking events is compared. Finally, an inter-comparison of results from RO data to different re-analyses, such as ERA-Interim, MERRA 2, and JRA-55, is presented. Brunner, L., A. K. Steiner, B. Scherllin-Pirscher, and M. W. Jury (2016): Exploring atmospheric blocking with GPS radio occultation observations. Atmos. Chem. Phys., 16, 4593-4604, doi:10.5194/acp-16-4593-2016.

Effects of different loading patterns on the trabecular bone morphology of the proximal femur using adaptive bone remodeling.

PubMed

Banijamali, S Mohammad Ali; Oftadeh, Ramin; Nazarian, Ara; Goebel, Ruben; Vaziri, Ashkan; Nayeb-Hashemi, Hamid

2015-01-01

In this study, the changes in the bone density of human femur model as a result of different loadings were investigated. The model initially consisted of a solid shell representing cortical bone encompassing a cubical network of interconnected rods representing trabecular bone. A computationally efficient program was developed that iteratively changed the structure of trabecular bone by keeping the local stress in the structure within a defined stress range. The stress was controlled by either enhancing existing beam elements or removing beams from the initial trabecular frame structure. Analyses were performed for two cases of homogenous isotropic and transversely isotropic beams.Trabecular bone structure was obtained for three load cases: walking, stair climbing and stumbling without falling. The results indicate that trabecular bone tissue material properties do not have a significant effect on the converged structure of trabecular bone. In addition, as the magnitude of the loads increase, the internal structure becomes denser in critical zones. Loading associated with the stumbling results in the highest density;whereas walking, considered as a routine daily activity, results in the least internal density in different regions. Furthermore, bone volume fraction at the critical regions of the converged structure is in good agreement with previously measured data obtained from combinations of dual X-ray absorptiometry (DXA) and computed tomography (CT). The results indicate that the converged bone architecture consisting of rods and plates are consistent with the natural bone morphology of the femur. The proposed model shows a promising means to understand the effects of different individual loading patterns on the bone density.

The effect of vacuum assisted socket suspension on prospective, community-based falls by users of lower limb prostheses.

PubMed

Rosenblatt, Noah J; Ehrhardt, Tess

2017-06-01

Individuals with lower limb amputation are at increased risk of falling compared to age-matched peers. The purpose of this study was to quantify the effect of socket suspension on the risk of falling, by comparing prospectively tracked falls between a group of participants that used vacuum assisted socket suspension (VASS) and a group that did not use this system. Fifteen current users of VASS and 12 non-VASS users received an email every two weeks for one year, with a link to an online survey that asked whether they fell (i.e., "unintentionally came to rest on a lower surface") or stumbled (i.e., lost balance but did not fall) in the prior two weeks. A Chi-squared test was used to compare fall and stumble risk between groups, after stratifying by level of amputation, and the phi coefficient (φ) was used to quantify effect size. While the use of VASS did not affect the rate of falling (i.e., falls per person year) for either persons with transtibial amputation (TTA) or those with transfemoral amputation (TFA), the absolute risk of having multiple falls was reduced by nearly 75% in the former (φ=0.83), which is particularly important given that recurrent falls are associated with more severe injuries. There was no effect of VASS on the risk of falls in TFA. Further work is warranted to demonstrate the persistence of these effects in larger, more controlled samples. Copyright © 2017 Elsevier B.V. All rights reserved.

49 CFR 587.14 - Deformable face component dimensions and material specifications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... tolerance of ±2.5 mm (0.1 in) unless otherwise specified. (a) Main honeycomb block. (1) Dimensions. The main honeycomb block has a height of 650 mm (25.6 in) (in the direction of honeycomb ribbon axis), a width of 1,000 mm (39.4 in), and a depth of 450 mm (17.7 in)(in the direction of honeycomb cell axis). (2...

49 CFR 587.14 - Deformable face component dimensions and material specifications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... tolerance of ±2.5 mm (0.1 in) unless otherwise specified. (a) Main honeycomb block. (1) Dimensions. The main honeycomb block has a height of 650 mm (25.6 in) (in the direction of honeycomb ribbon axis), a width of 1,000 mm (39.4 in), and a depth of 450 mm (17.7 in)(in the direction of honeycomb cell axis). (2...

49 CFR 587.14 - Deformable face component dimensions and material specifications.

Code of Federal Regulations, 2014 CFR

2014-10-01

... tolerance of ±2.5 mm (0.1 in) unless otherwise specified. (a) Main honeycomb block. (1) Dimensions. The main honeycomb block has a height of 650 mm (25.6 in) (in the direction of honeycomb ribbon axis), a width of 1,000 mm (39.4 in), and a depth of 450 mm (17.7 in)(in the direction of honeycomb cell axis). (2...

49 CFR 587.14 - Deformable face component dimensions and material specifications.

Code of Federal Regulations, 2013 CFR

2013-10-01

... tolerance of ±2.5 mm (0.1 in) unless otherwise specified. (a) Main honeycomb block. (1) Dimensions. The main honeycomb block has a height of 650 mm (25.6 in) (in the direction of honeycomb ribbon axis), a width of 1,000 mm (39.4 in), and a depth of 450 mm (17.7 in)(in the direction of honeycomb cell axis). (2...

49 CFR 587.14 - Deformable face component dimensions and material specifications.

Code of Federal Regulations, 2011 CFR

2011-10-01

... tolerance of ±2.5 mm (0.1 in) unless otherwise specified. (a) Main honeycomb block. (1) Dimensions. The main honeycomb block has a height of 650 mm (25.6 in) (in the direction of honeycomb ribbon axis), a width of 1,000 mm (39.4 in), and a depth of 450 mm (17.7 in)(in the direction of honeycomb cell axis). (2...

Significant role of structural fractures in Ren-Qiu buried-block oil field, eastern China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fei, Q.; Xie-Pei, W.

1983-03-01

Ren-qui oil field is in a buried block of Sinian (upper Proterozoic) rocks located in the Ji-zhong depression of the western Bohai Bay basin in eastern China. The main reservoir consists of Sinian dolomite rocks. It is a fault block with a large growth fault on the west side which trends north-northeast with throws of up to 1 km (0.6 mi) or more. The source rocks for the oil are Paleogene age and overlie the Sinian dolomite rocks. The structural fractures are the main factor forming the reservoir of the buried-block oil field. Three structural lines, trending northeast, north-northeast, andmore » northwest, form the regional netted fracture system. The north-northeast growth fault controlled the structural development of the buried block. The block was raised and eroded before the Tertiary sediments were deposited. In the Eocene Epoch, the Ji-zhong depression subsided, but the deposition, faulting, and related uplift of the block happened synchronously as the block was gradually submerged. At the same time, several horizontal and vertical karst zones were formed by the karst water along the netted structural fractures. The Eocene oil source rocks lapped onto the block and so the buried block, with many developed karst fractures, was surrounded by a great thickness of source rocks. As the growth fault developed, the height of the block was increased from 400 m (1300 ft) before the Oligocene to 1300 m (4250 ft) after. As the petroleum was generated, it migrated immediately into the karst fractures of the buried block along the growth fault. The karst-fractured block reservoir has an 800-m (2600-ft) high oil-bearing closure and good connections developed between the karst fractures.« less

Risk assessment of maintenance operations: the analysis of performing task and accident mechanism.

PubMed

Carrillo-Castrillo, Jesús A; Rubio-Romero, Juan Carlos; Guadix, Jose; Onieva, Luis

2015-01-01

Maintenance operations cover a great number of occupations. Most small and medium-sized enterprises lack the appropriate information to conduct risk assessments of maintenance operations. The objective of this research is to provide a method based on the concepts of task and accident mechanisms for an initial risk assessment by taking into consideration the prevalence and severity of the maintenance accidents reported. Data were gathered from 11,190 reported accidents in maintenance operations in the manufacturing sector of Andalusia from 2003 to 2012. By using a semi-quantitative methodology, likelihood and severity were evaluated based on the actual distribution of accident mechanisms in each of the tasks. Accident mechanisms and tasks were identified by using those variables included in the European Statistics of Accidents at Work methodology. As main results, the estimated risk of the most frequent accident mechanisms identified for each of the analysed tasks is low and the only accident mechanisms with medium risk are accidents when lifting or pushing with physical stress on the musculoskeletal system in tasks involving carrying, and impacts against objects after slipping or stumbling for tasks involving movements. The prioritisation of public preventive actions for the accident mechanisms with a higher estimated risk is highly recommended.

Occupational Accidents with Agricultural Machinery in Austria.

PubMed

Kogler, Robert; Quendler, Elisabeth; Boxberger, Josef

2016-01-01

The number of recognized accidents with fatalities during agricultural and forestry work, despite better technology and coordinated prevention and trainings, is still very high in Austria. The accident scenarios in which people are injured are very different on farms. The common causes of accidents in agriculture and forestry are the loss of control of machine, means of transport or handling equipment, hand-held tool, and object or animal, followed by slipping, stumbling and falling, breakage, bursting, splitting, slipping, fall, and collapse of material agent. In the literature, a number of studies of general (machine- and animal-related accidents) and specific (machine-related accidents) agricultural and forestry accident situations can be found that refer to different databases. From the database Data of the Austrian Workers Compensation Board (AUVA) about occupational accidents with different agricultural machinery over the period 2008-2010 in Austria, main characteristics of the accident, the victim, and the employer as well as variables on causes and circumstances by frequency and contexts of parameters were statistically analyzed by employing the chi-square test and odds ratio. The aim of the study was to determine the information content and quality of the European Statistics on Accidents at Work (ESAW) variables to evaluate safety gaps and risks as well as the accidental man-machine interaction.

Masquerading bundle branch block as a presenting manifestation of complete atrioventricular block that caused syncope.

PubMed

Jiao, Zhenyu; Tian, Ying; Yang, Xinchun; Liu, Xingpeng

2017-10-01

A 59-year-old male patient was admitted with the main complaints of stuffiness and shortness of breath. An ECG from precordial leads on admission showed masquerading bundle branch block. Syncope frequently occurred after admission. During syncope episodes, ECG telemetry showed that the syncope was caused by intermittent complete atrioventricular block, with the longest RR interval lasting for 4.36 s. At the gap of syncope, ECG showed complete right bundle branch block accompanied by alternation of left anterior fascicular block and left posterior fascicular block. The patient was implanted with a dual-chamber permanent pacemaker. Follow-up of 9 months showed no reoccurrence of syncope.

The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers.

PubMed

Tian, Mi; Deng, Zhu; Meng, Zhaokun; Li, Rui; Zhang, Zhiyi; Qi, Wenhui; Wang, Rui; Yin, Tingting; Ji, Menghui

2018-01-01

Children's block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children's block building performance. Chinese preschoolers ( N = 180) participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children's block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation.

A Value-Based Case Study to Increasing Community Mentoring in STEM for Hispanic Students

NASA Astrophysics Data System (ADS)

Moreno, Gilberto

This case study investigates the implementation of a unique community-driven mentoring pilot program (PASOS2) forging stronger community and K-12 partnerships. Focused on surfacing what matters most in engaging community mentors, this case study explores a civic organization's quest to impact, expand, and bring value via mentoring to Hispanic students' pursuit of post-secondary studies with emphasis in STEM careers. A major stumbling block faced by many underprivileged students is the lack of mentorship vital to expanding their social capital support system. This innovative mentoring approach provides students with critical access to STEM community empowerment agents supporting aspiring students' dreams. Analytical methods and principles of case study research focus on how community mentor choices impact community mentorship value. The study examines whether or not a formal mentoring system with a value-driven mentoring curriculum matters in attracting, preparing, and sustaining community mentors to advocate for STEM careers to Hispanic students. A mentor value equation is introduced correlating mentor capacity to build student relationships, demystify STEM, deliver career guidance, and fortify student readiness. A formal mentor development training program integrates a technology-based 'grit' software platform to enhance student awareness, understanding, and commitment to considering a STEM career. Through the investigation of a formal mentoring experience, the study reveals what best practices, tools, and techniques influence community mentor engagement. The findings of this case study underscore the value in preparing community mentor capacity and competency. The very nature of the PASOS2 project being civic community-based informs other communities on how their investments can fortify Hispanic student social capital in their successful pursuit of STEM careers.

Adolescent Social Isolation as a Model of Heightened Vulnerability to Comorbid Alcoholism and Anxiety Disorders

PubMed Central

Butler, Tracy R.; Karkhanis, Anushree N.; Jones, Sara R.; Weiner, Jeffrey L.

2016-01-01

Individuals diagnosed with anxiety-related illnesses are at increased risk of developing alcoholism, exhibit a telescoped progression of this disease and fare worse in recovery, relative to alcoholics that do not suffer from a comorbid anxiety disorder. Similarly, preclinical evidence supports the notion that stress and anxiety represent major risk factors for the development of alcohol use disorder (AUD). Despite the importance of understanding the link between anxiety and alcoholism, much remains unknown about the neurobiological substrates underlying this relationship. One stumbling block has been the lack of animal models that reliably reproduce the spectrum of behaviors associated with increased vulnerability to these diseases. Here, we review the literature that has examined the behavioral and neurobiological outcomes of a simple rodent adolescent social isolation procedure and discuss its validity as a model of vulnerability to comorbid anxiety disorders and alcoholism. Recent studies have provided strong evidence that adolescent social isolation of male rats leads to the expression of a variety of behaviors linked with increased vulnerability to anxiety and/or AUD, including deficits in sensory gating and fear extinction, and increases in anxiety measures and ethanol drinking. Neurobiological studies are beginning to identify mesolimbic adaptations that may contribute to the behavioral phenotype engendered by this model. Some of these changes include increased excitability of ventral tegmental area dopamine neurons and pyramidal cells in the basolateral amygdala and significant alterations in baseline and stimulated catecholamine signaling. A growing body of evidence suggests that adolescent social isolation may represent a reliable rodent model of heightened vulnerability to anxiety disorders and alcoholism in male rats. These studies provide initial support for the face, construct, and predictive validity of this model and highlight its utility in identifying neurobiological adaptations associated with increased risk of developing these disorders. PMID:27154240

Inhibitory effect of genistein on the invasive potential of human cervical cancer cells via modulation of matrix metalloproteinase-9 and tissue inhibitors of matrix metalloproteinase-1 expression.

PubMed

Hussain, Arif; Harish, Geetganga; Prabhu, Sathyen Alwin; Mohsin, Javeria; Khan, Munawwar Ali; Rizvi, Tahir A; Sharma, Chhavi

2012-12-01

One of the most challenging stumbling blocks for the treatment of cancer is the ability of cancer cells to break the natural barriers and spread from its site of origin to non-adjacent regional and distant sites, accounting for high cancer mortality rates. Gamut experimental and epidemiological data advocate the use of pharmacological or nutritional interventions to inhibit or delay various stage(s) of cancer such as invasion and metastasis. Genistein, a promising chemopreventive agent, has gained considerable attention for its powerful anti-carcinogenic, anti-angiogenic and chemosensitizing activities. In this study, the cytotoxic potential of genistein on HeLa cells by cell viability assay and the mode of cell death induced by genistein were determined by nuclear morphological examination, DNA laddering assay and cell cycle analysis. Moreover, to establish its inhibitory effect on migration of HeLa cells, scratch wound assay was performed and these results were correlated with the expression of genes involved in invasion and migration (MMP-9 and TIMP-1) by RT-PCR. The exposure of HeLa cells to genistein resulted in significant dose- and time-dependent growth inhibition, which was found to be mediated by apoptosis and cell cycle arrest at G(2)/M phase. In addition, it induced migration-inhibition in a time-dependent manner by modulating the expression of MMP-9 and TIMP-1. Our results signify that genistein may be an effective anti-neoplastic agent to prevent cancer cell growth and invasion and metastasis. Therefore therapeutic strategies utilizing genistein could be developed to substantially reduce cancer morbidity and mortality. Copyright © 2012 Elsevier Ltd. All rights reserved.

Prevalence of SGHV among tsetse species of economic importance in Tanzania and their implication for SIT application.

PubMed

Malele, Imna I; Manangwa, Oliver; Nyingilili, Hamisi H; Kitwika, Winston A; Lyaruu, Eugene A; Msangi, Atway R; Ouma, Johnson O; Nkwangulila, Gamba; Abd-Alla, Adly M M

2013-03-01

Sterile Insect technique is an important component in area-wide integrated tsetse control. The presence of the salivary glands hypertrophy virus (SGHV) in the wild tsetse, which are the seeds for colony adaptations in the laboratory has become a stumbling block in establishing and maintaining colonies in the laboratory. The virus is transmitted both vertically (in the wild) and horizontally (in the laboratory). However, its prevalence is magnified in the laboratory as a result of the use of in vitro membrane feeding regimen. Fly species of Glossina fuscipes fuscipes, G. pallidipes, G. morsitans and G. swynnertoni were collected from the coastal and inland areas of Tanzania and virus infection rates were assessed microscopically and by PCR. The data showed that in a period of 4years, the virus was present in all species tested irrespective of their ages, sex, and season of the year. However, infection levels differed among species and from one location to another. Symptomatic infection determined by dissection was 1.2% (25/2164) from the coast as compared to 0.4% (6/1725) for inland collected flies. PCR analysis indicated a higher infection rate of 19.81% (104/525) of asymptomatic flies. From these observations, we conclude that care should be taken when planning to initiate tsetse laboratory colonies for use in SIT eradication program. All efforts should be made to select non-infected flies when initiating laboratory colonies and to try to minimize the infection with SGHV. Also management of SGHV infection in the established colony should be applied. Copyright © 2013 International Atomic Energy Agency. Published by Elsevier Inc. All rights reserved.

MGMT Inhibition Restores ERα Functional Sensitivity to Antiestrogen Therapy

PubMed Central

Bobustuc, George C; Smith, Joshua S; Maddipatla, Sreeram; Jeudy, Sheila; Limaye, Arati; Isley, Beth; Caparas, Maria-Lourdes M; Constantino, Susan M; Shah, Nikita; Baker, Cheryl H; Srivenugopal, Kalkunte S; Baidas, Said; Konduri, Santhi D

2012-01-01

Antiestrogen therapy resistance remains a huge stumbling block in the treatment of breast cancer. We have found significant elevation of O6 methylguanine DNA methyl transferase (MGMT) expression in a small sample of consecutive patients who have failed tamoxifen treatment. Here, we show that tamoxifen resistance is accompanied by upregulation of MGMT. Further we show that administration of the MGMT inhibitor, O6-benzylguanine (BG), at nontoxic doses, leads to restoration of a favorable estrogen receptor alpha (ERα) phosphorylation phenotype (high p-ERα Ser167/low p-ERα Ser118), which has been reported to correlate with sensitivity to endocrine therapy and improved survival. We also show BG to be a dual inhibitor of MGMT and ERα. In tamoxifen-resistant breast cancer cells, BG alone or in combination with antiestrogen (tamoxifen [TAM]/ICI 182,780 [fulvestrant, Faslodex]) therapy enhances p53 upregulated modulator of apoptosis (PUMA) expression, cytochrome C release and poly (ADP-ribose) polymerase (PARP) cleavage, all indicative of apoptosis. In addition, BG increases the expression of p21cip1/waf1. We also show that BG, alone or in combination therapy, curtails the growth of tamoxifen-resistant breast cancer in vitro and in vivo. In tamoxifen-resistant MCF7 breast cancer xenografts, BG alone or in combination treatment causes significant delay in tumor growth. Immunohistochemistry confirms that BG increases p21cip1/waf1 and p-ERα Ser167 expression and inhibits MGMT, ERα, p-ERα Ser118 and ki-67 expression. Collectively, our results suggest that MGMT inhibition leads to growth inhibition of tamoxifen-resistant breast cancer in vitro and in vivo and resensitizes tamoxifen-resistant breast cancer cells to antiestrogen therapy. These findings suggest that MGMT inhibition may provide a novel therapeutic strategy for overcoming antiestrogen resistance. PMID:22549111

We Can Recruit Minorities Into The Geosciences

NASA Astrophysics Data System (ADS)

O'Connell, S.

2011-12-01

Despite the dismal numbers, efforts to recruit minorities into the geosciences are improving, thanks in part to NSF's "Opportunities for Enhancing Diversity in the Geosciences" (OEDG) initiative. At Wesleyan University, a small liberal arts college in Connecticut, we have significantly increased our recruitment of minority students. Twenty percent (four students) of the class of 2013 are African American. Most of the recruitment is done on an individual basis and working in conjunction with the "Dean for Diversity and Student Engagement" and courting minority students in introductory classes. The Dean for Diversity and Student Engagement is aware of our interest in increasing diversity and that we are able to hire minority students during the academic year and through the summer with OEDG funds. When she identifies minority students who might be interested in the geosciences, she refers them to faculty in the Earth and Environmental Sciences Department. Our faculty can provide employment, mentoring and a variety of geo-related experiences. Courting students in introductory courses can include inviting them to lunch or other activity, and attending sports, theater or dance events in which they are participating. Not all efforts result in new majors. Courses in ancillary sciences may be stumbling blocks and higher grades in less demanding courses have lured some students into other majors. Nevertheless, we now have a large enough cohort of minority students so that minority students from other majors visit their friends in our labs. A critical mass? Even a student, who chooses another major, may continue an interest in geoscience and through outreach efforts and discussions with younger family members, may provide a bridge that becomes a conduit for future students.

A Kernel for Open Source Drug Discovery in Tropical Diseases

PubMed Central

Ortí, Leticia; Carbajo, Rodrigo J.; Pieper, Ursula; Eswar, Narayanan; Maurer, Stephen M.; Rai, Arti K.; Taylor, Ginger; Todd, Matthew H.; Pineda-Lucena, Antonio; Sali, Andrej; Marti-Renom, Marc A.

2009-01-01

Background Conventional patent-based drug development incentives work badly for the developing world, where commercial markets are usually small to non-existent. For this reason, the past decade has seen extensive experimentation with alternative R&D institutions ranging from private–public partnerships to development prizes. Despite extensive discussion, however, one of the most promising avenues—open source drug discovery—has remained elusive. We argue that the stumbling block has been the absence of a critical mass of preexisting work that volunteers can improve through a series of granular contributions. Historically, open source software collaborations have almost never succeeded without such “kernels”. Methodology/Principal Findings Here, we use a computational pipeline for: (i) comparative structure modeling of target proteins, (ii) predicting the localization of ligand binding sites on their surfaces, and (iii) assessing the similarity of the predicted ligands to known drugs. Our kernel currently contains 143 and 297 protein targets from ten pathogen genomes that are predicted to bind a known drug or a molecule similar to a known drug, respectively. The kernel provides a source of potential drug targets and drug candidates around which an online open source community can nucleate. Using NMR spectroscopy, we have experimentally tested our predictions for two of these targets, confirming one and invalidating the other. Conclusions/Significance The TDI kernel, which is being offered under the Creative Commons attribution share-alike license for free and unrestricted use, can be accessed on the World Wide Web at http://www.tropicaldisease.org. We hope that the kernel will facilitate collaborative efforts towards the discovery of new drugs against parasites that cause tropical diseases. PMID:19381286

Communications Effects Server (CES) Model for Systems Engineering Research

DTIC Science & Technology

2012-01-31

Visualization Tool Interface «logical» HLA Tool Interface «logical» DIS Tool Interface «logical» STK Tool Interface «module» Execution Kernels «logical...interoperate with STK when running simulations. GUI Components  Architect – The Architect represents the main network design and visualization ...interest» CES «block» Third Party Visualization Tool «block» Third Party Analysis Tool «block» Third Party Text Editor «block» HLA Tools Analyst User Army

Convergence to Diagonal Form of Block Jacobi-type Processes

NASA Astrophysics Data System (ADS)

Hari, Vjeran

2008-09-01

The main result of recent research on convergence to diagonal form of block Jacobi-type processes is presented. For this purpose, all notions needed to describe the result are introduced. In particular, elementary block transformation matrices, simple and non-simple algorithms, block pivot strategies together with the appropriate equivalence relations are defined. The general block Jacobi-type process considered here can be specialized to take the form of almost any known Jacobi-type method for solving the ordinary or the generalized matrix eigenvalue and singular value problems. The assumptions used in the result are satisfied by many concrete methods.

[Development of a portable fall risk index for elderly people living in the community].

PubMed

Toba, Kenji; Okochi, Jiro; Takahashi, Tai; Matsubayashi, Kozo; Nishinaga, Masanori; Yamada, Shizuru; Takahashi, Ryutaro; Nishijima, Reiko; Kobayashi, Yoshio; Machida, Ayako; Akishita, Masahiro; Sasaki, Hidetada

2005-05-01

To develop a portable risk index for falls. Risk factors were chosen from previously established factors then we added several environmental factors to the risk index; previous falls in the last 12 month, trippig or stumbling, inability to ascend or descend stairs without help, decreased walking speed, inability to cross a road within the green signal interval, inability to walk 1km without a break, inability to stand on one leg for 5 seconds (eyes open), using a cane, inability to wring out a towel, dizziness or faintness, stooped or rounded back, knee joint pain, visual disturbance, hearing disturbance, cognitive decline, fear of falling, receiving 5 or more prescribed drugs, sensation of darkness at home, obstacles inside, barrier on the carpet or floor, using steps daily at home, steep slopes around home. The questionnaire sheet was completed by 2,439 community-dwelling elderly subjects (76.3 +/- 7.4 years old). The frequency of each items of fall risk index was compared between fallers (history of fall within one year) and non-fallers. Multiple regression analysis was performed to identify independent risk factors for previous falls. Except barrier, step use and steep slope around home, all items in the fall risk index were more frequent in fallers. Multivariate analysis revealed that tripping or stumbling, inability to cross a road within the green signal interval, dizziness or faintness, obstacles inside, inability to wring out a towel, cane use and knee joint pain were independent risk factors for previous falls. These 7 selected items were further analyzed as predictors. The maximum sum of sensitivity and specificity was reached at the cut-off point of 2/3 (sensitivity 0.65, specificity 0.72) by receiver operating curve. Portable fall risk index is useful for clinical settings to identify high-risk subjects.

Timing of terrane accretion in eastern and east-central Maine

NASA Astrophysics Data System (ADS)

Ludman, Allan

1986-05-01

The Norumbega fault zone is often cited as a post-Acadian suture between exotic blocks, even though stratigraphic, structural, and metamorphic data indicate that there is little offset of the Silurian-Devonian strata that the zone cuts in eastern Maine. Similarly, the Kingman fault zone has been shown by gravity and geochemical studies to separate distinct crustal blocks, whereas mapping shows that it lies entirely within a Silurian turbidite package. These conflicts are resolved if the two fault zones represent boundaries between Ordovician or older crustal blocks that had accreted to form a composite terrane prior to deposition of the cover sequences. The faults now mapped within these younger rocks formed by reactivation of the pre-Silurian boundaries during late Acadian time; movement continued until the late Carboniferous. Most of the accretionary history of Maine had thus ended before the Silurian. A complex composite terrane may have formed during Cambrian-Ordovician time that (1) interacted with cratonic North America during the Taconian orogeny and (2) became the “basement” upon which the Silurian and Lower Devonian strata of eastern Maine were deposited.

24. Perspective view of central tower from roof of main ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. Perspective view of central tower from roof of main block, looking northeast, with HABS team - National Home for Disabled Volunteer Soldiers, Northwestern Branch, Main Building, 5000 West National Avenue, Milwaukee, Milwaukee County, WI

Geological and Geochemical Characteristics of Skarn Type Lead-Zinc Deposit in Baoshan Block, Yunnan Province

NASA Astrophysics Data System (ADS)

Yao, Xue; Wang, Peng

2017-11-01

Baoshan block is an important Pb-Zn-Fe-Cu polymetallic ore-concentration area which is located in southern of the Sanjiang metallogenic belt in western Yunnan. The article is studying about the geological and geochemical characteristics of the skarn type lead-zinc deposit in Baoshan block. The skarn-type lead-zinc deposit Baoshan block is characterized by skarn and skarn marble, and the orebodies are layered, or bedded along the interlayer fault, which are significantly controlled by structure. The research about Stable isotope S, H and O indicates that the ore-forming fluids are mainly derived from magmatic water, partly mixed with parts of metamorphic water and atmospheric precipitation. The initial Sr isotopic Sr87/Sr86 ratio suggests that the ore-forming materials derived from deep concealed magmatic rock, age of Rb-Sr mineralization is similar to that of Yanshanian granite. In conclusion, the Yanshanian tectonic-magmatic-fluid coupling mineralization of Yanshan formation is the main reason for the skarn-type lead-zinc deposit in the Baoshan block.

Program Aids Specification Of Multiple-Block Grids

NASA Technical Reports Server (NTRS)

Sorenson, R. L.; Mccann, K. M.

1993-01-01

3DPREP computer program aids specification of multiple-block computational grids. Highly interactive graphical preprocessing program designed for use on powerful graphical scientific computer workstation. Divided into three main parts, each corresponding to principal graphical-and-alphanumerical display. Relieves user of some burden of collecting and formatting many data needed to specify blocks and grids, and prepares input data for NASA's 3DGRAPE grid-generating computer program.

Comments on the Yule Marble Haines block: potential replacement, Tomb of the Unknown Soldier, Arlington National Cemetery

USGS Publications Warehouse

Mossotti, Victor G.

2014-01-01

Marble for the Tomb of the Unknown Soldier at Arlington National Cemetery was cut from the Colorado Yule Marble Quarry in 1931. Although anecdotal reports suggest that cracks were noticed in the main section of the monument shortly after its installation at the Arlington National Cemetery in Arlington, Virginia, detailed documentation of the extent of cracking did not appear until 1963. Although debate continues as to whether the main section of the Tomb of the Unknowns monument should be repaired or replaced, Mr. John S. Haines of Glenwood Springs, Colorado, in anticipation of the permanent closing of the Yule Quarry, donated a 58-ton block of Yule Marble, the so-called Haines block, as a potential backup. The brief study reported here was conducted during mid-summer 2009 at the behest of the superintendent of Arlington National Cemetery. The field team entered the subterranean Yule Marble Quarry with the Chief Extraction Engineer in order to contrast the method used for extraction of the Haines block with the method that was probably used to extract the marble block that is now cracked. Based on surficial inspection and shallow coring of the Haines block, and on the nature of crack propagation in Yule Marble as judged by close inspection of a large collection of surrogate Yule Marble blocks, the team found the block to be structurally sound and cosmetically equivalent to the marble used for the current monument. If the Haines block were needed, it would be an appropriate replacement for the existing cracked section of the Tomb of the Unknown Soldier Monument.

The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers

PubMed Central

Tian, Mi; Deng, Zhu; Meng, Zhaokun; Li, Rui; Zhang, Zhiyi; Qi, Wenhui; Wang, Rui; Yin, Tingting; Ji, Menghui

2018-01-01

Children’s block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children’s block building performance. Chinese preschoolers (N = 180) participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children’s block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation. PMID:29441031

Microbial Communities in Long-Term, Water-Flooded Petroleum Reservoirs with Different in situ Temperatures in the Huabei Oilfield, China

PubMed Central

Tang, Yue-Qin; Li, Yan; Zhao, Jie-Yu; Chi, Chang-Qiao; Huang, Li-Xin; Dong, Han-Ping; Wu, Xiao-Lei

2012-01-01

The distribution of microbial communities in the Menggulin (MGL) and Ba19 blocks in the Huabei Oilfield, China, were studied based on 16S rRNA gene analysis. The dominant microbes showed obvious block-specific characteristics, and the two blocks had substantially different bacterial and archaeal communities. In the moderate-temperature MGL block, the bacteria were mainly Epsilonproteobacteria and Alphaproteobacteria, and the archaea were methanogens belonging to Methanolinea, Methanothermobacter, Methanosaeta, and Methanocella. However, in the high-temperature Ba19 block, the predominant bacteria were Gammaproteobacteria, and the predominant archaea were Methanothermobacter and Methanosaeta. In spite of shared taxa in the blocks, differences among wells in the same block were obvious, especially for bacterial communities in the MGL block. Compared to the bacterial communities, the archaeal communities were much more conserved within blocks and were not affected by the variation in the bacterial communities. PMID:22432032

Block structure and geodynamics of the continental lithosphere on plate boundaries

NASA Astrophysics Data System (ADS)

Gatinsky, Yu. G.; Prokhorova, T. V.; Romanyuk, T. V.; Vladova, G. L.

2009-04-01

Division of the Earth lithosphere on large plates must be considered only as the first and most general approximation in its structure hierarchy. Some transit zones or difuuse boundaries after other authors take place in lithosphere plate boundaries. The tectonic tension of plate interaction is transferred and relaxed within these zones, which consist of blocks limited by seismoactive faults. Vectors of block horizontal displacements often don't coincide with vectors of main plates and change together with changing block rigidity. As a rule the intensity the seismic energy at plate and transit zone boundaries decreases linearly with distancing from these boundaries and correlates with decreasing of velocities of block horizontal displacements. But sometimes the maximum of the energy manifestation takes place in inner parts of transit zones. Some relatively tight interblock zones established in central and east Asia are the most seismically active. They limited such blocks as Pamir, Tien Shan, Bayanhar, Shan, Japanese-Korean, as well as the north boundary of the Indian Plate. A seismic energy intensity of these zones can be compared with the energy of Pacific subduction zones. It is worthy to note that the majority catastrophic earthquakes took place in Central Asia just within interblock zones. A level of block displacement is situated mainly in the bottom or inside the Earth crust, more rare in the lithosphere mantle. Blocks with the most thick lithosphere roots (SE China, Amurian) are the most rigid and weakly deformed.

Bulkhead insert for an internal combustion engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maki, Clifford E.; Chottiner, Jeffrey Eliot; Williams, Rick L.

An engine includes a cylinder block defining at least one main bearing bulkhead adjacent to a cylinder, and a crankshaft rotatably housed within the block by a main bearing. A bulkhead insert has a cap portion, and an insert portion provided within the bulkhead. The insert portion has having first and second end regions connected by first and second straps. Each strap having a flanged beam cross section. The first and second ends of the insert portion are configured to connect a main bearing cap column to a cylinder head column. Each of the first and second end regions definemore » at least one protrusion having a surface substantially normal to engine combustion and reactive loads. The cap portion is configured to mate with the first end region at the main bearing cap column and support the main bearing.« less

Comprehensive assessment of the efficiency of high-rise construction projects in the form of urban blocks

NASA Astrophysics Data System (ADS)

Orlov, Alexandr; Chubarkina, Irina

2018-03-01

The paper is dedicated to main modern trends in the area of high-rise construction. The classification of buildings and structures by height is given. Functional distribution by the height of buildings is presented. A review of positive and negative aspects of high-rise construction from the economic point of view is given. On the basis of the data obtained, it is proposed to build up residential microdistricts in the form of urban blocks. A plan of microdistricts development is presented. It takes into account urban blocks and includes their main characteristics. An economic and mathematical model was developed to carry out a comprehensive assessment of the effectiveness of high-rise construction projects.

Late-Paleozoic-Mesozoic deformational and deformation related metamorphic structures of Kuznetsk-Altai region

NASA Astrophysics Data System (ADS)

Zinoviev, Sergei

2014-05-01

Kuznetsk-Altai region is a part of the Central Asian Orogenic Belt. The nature and formation mechanisms of the observed structure of Kuznetsk-Altai region are interpreted by the author as the consequence of convergence of Tuva-Mongolian and Junggar lithospheric block structures and energy of collision interaction between the blocks of crust in Late-Paleozoic-Mesozoic period. Tectonic zoning of Kuznetsk-Altai region is based on the principle of adequate description of geological medium (without methods of 'primary' state recovery). The initial indication of this convergence is the crust thickening in the zone of collision. On the surface the mechanisms of lateral compression form a regional elevation; with this elevation growth the 'mountain roots' start growing. With an approach of blocks an interblock elevation is divided into various fragments, and these fragments interact in the manner of collision. The physical expression of collision mechanisms are periodic pulses of seismic activity. The main tectonic consequence of the block convergence and collision of interblock units is formation of an ensemble of regional structures of the deformation type on the basis of previous 'pre-collision' geological substratum [Chikov et al., 2012]. This ensemble includes: 1) allochthonous and autochthonous blocks of weakly deformed substratum; 2) folded (folded-thrust) systems; 3) dynamic metamorphism zones of regional shears and main faults. Characteristic of the main structures includes: the position of sedimentary, magmatic and PT-metamorphic rocks, the degree of rock dynamometamorphism and variety rock body deformation, as well as the styles and concentrations of mechanic deformations. 1) block terranes have weakly elongated or isometric shape in plane, and they are the systems of block structures of pre-collision substratum separated by the younger zones of interblock deformations. They stand out among the main deformation systems, and the smallest are included into the deformation systems. 2) folded (folded-thrust) deformation systems combine deformation zones with relic lenses of Paleozoid substratum, and predominantly conform systems of the main faults. Despite a high degree of regional deformation the sedimentary-stratified and intrusive-contact relations of geological bodies are stored within the deformation systems, and this differs in the main the collision systems from zones of dynamic metamorphism. 3) regional zones of dynamic metamorphism of Kuznetsk-Altai region are the concentration belts of multiple mechanic deformations and contrast dynamometamorphism of complexes. The formational basis of dynamic metamorphism zones is tectonites of the collision stage. Zones of dynamic metamorphism attract special attention in the structural model of Kuznetsk-Altai region. They not only form the typical tectonic framework of collision sutures, but also contain the main part of ore deposits of this region. Pulse mode of structure formation of Kuznetsk-Altai region is detected. Major collision events in Kuznetsk-Altai region were in the late-Carboniferous-Triassic time (307-310, 295-285, 260-250 and 240-220 Ma). This study was supported by a grant of the Russian Foundation for Basic Research (project nos. 14-05-00117).

Smartphone-Based Escalator Recognition for the Visually Impaired

PubMed Central

Nakamura, Daiki; Takizawa, Hotaka; Aoyagi, Mayumi; Ezaki, Nobuo; Mizuno, Shinji

2017-01-01

It is difficult for visually impaired individuals to recognize escalators in everyday environments. If the individuals ride on escalators in the wrong direction, they will stumble on the steps. This paper proposes a novel method to assist visually impaired individuals in finding available escalators by the use of smartphone cameras. Escalators are recognized by analyzing optical flows in video frames captured by the cameras, and auditory feedback is provided to the individuals. The proposed method was implemented on an Android smartphone and applied to actual escalator scenes. The experimental results demonstrate that the proposed method is promising for helping visually impaired individuals use escalators. PMID:28481270

A geologic and morphological description of Ishtar terra (Venus)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sukhanov, A.L.; Kotel'nikov, V.A.; Ostrovskii, M.V.

The main part of Ishtar Terra east of Maxwell Montes is covered by systems of area dislocations in several directions that are called ''parquet.'' From the structural pictures, 1) a stable central block, 2) smaller peripheral blocks separated from the central block by faults and grabens, 3) zones of mobilized parquet, the matter of which spread down below the slope in a direction away from the central block in the form of plastic flows, and 4) partially ''parquetized'' lava rock masses are distinguished here. The Maxwell Montes were formed as the result of the collision of the central block andmore » the Lakshmi Planum.« less

Cattaraugus Creek Harbor, New York General Design Memorandum. Phase II (Detailed Design). Volume I. Main Report-GDM II.

DTIC Science & Technology

1976-03-01

of the abetract entered In Block 20, If different from Report) I$. SUPPLEMENTARY NOTES .4 19. KEY WORDS (Continue on reverse aide If neceesary and...Identify by block number) Harbors Cattaraugus Creek Flood Control 20O T’rlq 4CT Caiweut -t reverse se 0 neceeeely mid Identify by block number) The... blocked by the sand bar and lake ice at the creek mouth. During discharges developed by the com- bination of rainfall and snow melt, ice jams raise the

Transient left septal and anterior fascicular block associated with type 1 electrocardiographic Brugada pattern.

PubMed

Pérez-Riera, Andrés Ricardo; Barbosa-Barros, Raimundo; Penachini da Costa de Rezende Barbosa, Marianne; Daminello-Raimundo, Rodrigo; de Abreu, Luiz Carlos

The left septal fascicular block (LSFB) or blockage of the middle fibers of the left bundle branch is probably caused mainly by - in the developed world - the proximal obstruction of the left anterior descending artery (LAD) before its first anterior septal perforator branch (S 1 ). The association of transient LSFB and left anterior fascicular block (LAFB) - left bifascicular block - and the electrocardiographic type 1 Brugada pattern (BrP) has not been described in the literature yet. Copyright © 2017 Elsevier Inc. All rights reserved.

Co-crystallization phase transformations in all π-conjugated block copolymers with different main-chain moieties.

PubMed

Lee, Yi-Huan; Chen, Wei-Chih; Yang, Yi-Lung; Chiang, Chi-Ju; Yokozawa, Tsutomu; Dai, Chi-An

2014-05-21

Driven by molecular affinity and balance in the crystallization kinetics, the ability to co-crystallize dissimilar yet self-crystallizable blocks of a block copolymer (BCP) into a uniform domain may strongly affect its phase diagram. In this study, we synthesize a new series of crystalline and monodisperse all-π-conjugated poly(2,5-dihexyloxy-p-phenylene)-b-poly(3-(2-ethylhexyl)thiophene) (PPP-P3EHT) BCPs and investigate this multi-crystallization effect. Despite vastly different side-chain and main-chain structures, PPP and P3EHT blocks are able to co-crystallize into a single uniform domain comprising PPP and P3EHT main-chains with mutually interdigitated side-chains spaced in-between. With increasing P3EHT fraction, PPP-P3EHTs undergo sequential phase transitions and form hierarchical superstructures including predominately PPP nanofibrils, co-crystalline nanofibrils, a bilayer co-crystalline/pure P3EHT lamellar structure, a microphase-separated bilayer PPP-P3EHT lamellar structure, and finally P3EHT nanofibrils. In particular, the presence of the new co-crystalline lamellar structure is the manifestation of the interaction balance between self-crystallization and co-crystallization of the dissimilar polymers on the resulting nanostructure of the BCP. The current study demonstrates the co-crystallization nature of all-conjugated BCPs with different main-chain moieties and may provide new guidelines for the organization of π-conjugated BCPs for future optoelectronic applications.

Block copolymer micelles with a dual-stimuli-responsive core for fast or slow degradation.

PubMed

Han, Dehui; Tong, Xia; Zhao, Yue

2012-02-07

We report the design and demonstration of a dual-stimuli-responsive block copolymer (BCP) micelle with increased complexity and control. We have synthesized and studied a new amphiphilic ABA-type triblock copolymer whose hydrophobic middle block contains two types of stimuli-sensitive functionalities regularly and repeatedly positioned in the main chain. Using a two-step click chemistry approach, disulfide and o-nitrobenzyle methyl ester groups are inserted into the main chain, which react to reducing agents and light, respectively. With the end blocks being poly(ethylene oxide), micelles formed by this BCP possess a core that can be disintegrated either rapidly via photocleavage of o-nitrobenzyl methyl esters or slowly through cleavage of disulfide groups by a reducing agent in the micellar solution. This feature makes possible either burst release of an encapsulated hydrophobic species from disintegrated micelles by UV light, or slow release by the action of a reducing agent, or release with combined fast-slow rate profiles using the two stimuli.

Lyme carditis with isolated left bundle branch block and myocarditis successfully treated with oral doxycycline.

PubMed

Cunha, Burke A; Elyasi, Maekal; Singh, Prince; Jimada, Ismail

2018-01-01

Lyme disease may present with a variety of cardiac manifestations ranging from first degree to third degree heart block. Cardiac involvement with Lyme disease may be asymptomatic, or symptomatic. Atrioventrical conduction abnormalities are the most common manifestation of Lyme carditis. Less common, are alternating right bundle branch block (RBBB) and left bundle branch block (LBBB). We present an interesting case of a young male whose main manifestation of Lyme carditis was isolated LBBB. He also had mild Lyme myocarditis. The patient was successfully treated with oral doxycycline, and his isolated LBBB and myocarditis rapidly resolved.

Fuel control for gas turbine engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stearns, C.F.; Tutherly, H.W.

1983-12-27

The basic gas turbine engine hydromechanical fuel control is adaptable to different engine configurations such as turbofan, turboprop and turboshaft engines by incorporating in the main housing those elements having a commonality to all engine configurations and providing a removable block for each configuration having the necessary control elements and flow passages required for that particular configuration. That is to say, a block with the elements peculiar to a turbofan engine could be replaced by a mating block that includes those elements peculiar to a turboshaft engine in adapting the control for a turboshaft configuration. Similarly another block with thosemore » elements peculiar to a turboprop engine could replace any of the other blocks in adapting the control to a turboprop configuration. Obviously the basic control has the necessary flow passages terminating at the interface with the block and these flow passages mate with corresponding passages in the block.« less

Radiolarian biochronology of upper Anisian to upper Ladinian (Middle Triassic) blocks and tectonic slices of volcano-sedimentary successions in the Mersin Mélange, southern Turkey: New insights for the evolution of Neotethys

NASA Astrophysics Data System (ADS)

Tekin, U. Kagan; Bedi, Yavuz; Okuyucu, Cengiz; Göncüoglu, M. Cemal; Sayit, Kaan

2016-12-01

The Mersin Ophiolitic Complex located in southern Turkey comprises two main structural units; the Mersin Mélange, and a well-developed ophiolite succession with its metamorphic sole. The Mersin Mélange is a sedimentary complex including blocks and tectonic slices of oceanic litosphere and continental crust in different sizes. Based on different fossil groups (Radiolaria, Conodonta, Foraminifera and Ammonoidea), the age of these blocks ranges from Early Carboniferous to early Late Cretaceous. Detailed fieldwork in the central part of the Mersin Mélange resulted in identification of a number of peculiar blocks of thick basaltic pillow-and massive lava sequences alternating with pelagic-clastic sediments and radiolarian cherts. The oldest ages obtained from the radiolarian assemblages from the pelagic sediments transitional to the volcano-sedimentary succession in some blocks are middle to late Late Anisian. These pelagic sediments are overlain by thick sandstones of latest Anisian to middle Early Ladinian age. In some blocks, sandstones are overlain by clastic and pelagic sediments with lower Upper to middle Upper Ladinian radiolarian fauna. Considering the litho- and biostratigraphical data from Middle Triassic successions in several blocks in the Mersin Mélange, it is concluded that they correspond mainly to the blocks/slices of the Beysehir-Hoyran Nappes, which were originated from the southern margin of the Neotethyan Izmir-Ankara Ocean. As the pre-Upper Anisian basic volcanics are geochemically evaluated as back-arc basalts, this new age finding suggest that a segment of the Izmir-Ankara branch of the Neotethys was already open prior to Middle Triassic and was the site of intraoceanic subduction.

NUCLEAR REACTOR CORE DESIGN

DOEpatents

Mahlmeister, J.E.; Peck, W.S.; Haberer, W.V.; Williams, A.C.

1960-03-22

An improved core design for a sodium-cooled, graphitemoderated nuclear reactor is described. The improved reactor core comprises a number of blocks of moderator material, each block being in the shape of a regular prism. A number of channels, extending the length of each block, are disposed around the periphery. When several blocks are placed in contact to form the reactor core, the channels in adjacent blocks correspond with each other to form closed conduits extending the length of the core. Fuel element clusters are disposed in these closed conduits, and liquid coolant is forced through the annulus between the fuel cluster and the inner surface of the conduit. In a preferred embodiment of the invention, the moderator blocks are in the form of hexagonal prisms with longitudinal channels cut into the corners of the hexagon. The main advantage of an "edge-loaded" moderator block is that fewer thermal neutrons are absorbed by the moderator cladding, as compared with a conventional centrally loaded moderator block.

Orbiter Atlantis (STS-110) Launch With New Block II Engines

NASA Technical Reports Server (NTRS)

2002-01-01

Powered by three newly-enhanced Space Shuttle Maine Engines (SSMEs), called the Block II Maine Engines, the Space Shuttle Orbiter Atlantis lifted off from the Kennedy Space Center launch pad on April 8, 2002 for the STS-110 mission. The Block II Main Engines incorporate an improved fuel pump featuring fewer welds, a stronger integral shaft/disk, and more robust bearings, making them safer and more reliable, and potentially increasing the number of flights between major overhauls. NASA continues to increase the reliability and safety of Shuttle flights through a series of enhancements to the SSME. The engines were modified in 1988 and 1995. Developed in the 1970s and managed by the Space Shuttle Projects Office at the Marshall Space Flight Center, the SSME is the world's most sophisticated reusable rocket engine. The new turbopump made by Pratt and Whitney of West Palm Beach, Florida, was tested at NASA's Stennis Space Center in Mississippi. Boeing Rocketdyne in Canoga Park, California, manufactures the SSME. This image was extracted from engineering motion picture footage taken by a tracking camera.

Stem cells and regenerative medicine on the Asian horizon: an economic, industry and social perspective.

PubMed

Sipp, Douglas

2009-11-01

For the past decade, forays into stem cell research and regenerative medicine by institutes and companies based in the Asia-Pacific region have attracted global attention at levels unprecedented in the life sciences. The unique combination of economic pressures, competitiveness and opportunism, laissez-faire regulation, burgeoning investment in the life sciences and rapidly growing markets, coupled with its great diversity, have propelled the region to surge forward in some areas, but to stumble in others. This article provides a historical and scientific context to the state of stem cell research and clinical applications in the region, and highlights trends and new possibilities to watch for on the Asian horizon.

Competency-based training to create the 21st century mental health workforce: strides, stumbles, and solutions.

PubMed

Delaney, Kathleen R; Carlson-Sabelli, Linnea; Shephard, Rebekah; Ridge, Alison

2011-08-01

In response to sustained concerns about the capability of the mental health workforce, federal groups have urged educators to adopt a competency-based system for training students in core mental health skills. A particular emphasis is training students to work in integrated systems, intervene with evidence-based practice, and employ culturally relevant therapies. Creating such a program, particularly one delivered online, requires structures that engage students in their own learning and tools for tracking competencies. We report on our competency-based graduate psychiatric mental health nursing program and the unique methods used to track student skill development and clinical reasoning. Copyright © 2011 Elsevier Inc. All rights reserved.

Historical Lessons in Translational Medicine: Cyclooxygenase Inhibition and P2Y12 Antagonism

PubMed Central

Fitzgerald, Desmond J.; FitzGerald, Garret A.

2013-01-01

The development of drugs that inhibit platelets has been driven by a combination of clinical insights, fundamental science and sheer luck. The process has evolved as the days of stumbling upon therapeutic gems like aspirin have long passed and have been replaced by an arduous process where a drug is designed to target a specific protein implicated in a well-characterized pathophysiological process. Or so we would like to believe. The development of antiplatelet therapy illustrates the importance of understanding the mechanisms of disease and the pharmacology of the compounds we develop, coupled with careful clinical experimentation and observation. And yes, still, a fair bit of luck. PMID:23287454

Block coals from Indiana: Inferences on changing depositional environment

USGS Publications Warehouse

Mastalerz, Maria; Padgett, P.L.; Eble, C.F.

2000-01-01

Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal Members are significant correlation tools applicable to mining exploration and chronostratigraphy. (C) 2000 Elsevier Science B.V. All rights reserved.Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal members are significant correlation tools applicable to mining exploration and chronostratigraphy.

Facile synthesis of main-chain degradable block copolymers for performance enhanced dismantlable adhesion.

PubMed

Sato, Eriko; Hagihara, Takashi; Matsumoto, Akikazu

2012-04-01

Block copolymers consisting of readily degradable polyperoxides and non-degradable vinyl polymers as the block segments were successfully synthesized by reversible chain transfer catalyzed polymerization, which is one of living radical polymerization techniques. The block copolymers showed characteristic morphology and wettability being different from the polymer blends. When block copolymers containing polyperoxide and polymethacrylate blocks were heated below 150 °C, the polyperoxide blocks were completely degraded and the polymethacrylate blocks were recovered without degradation. Block copolymers containing a poly(2-ethylhexyl methacrylate) block were then investigated as a dismantlable adhesion material, which requires adequate bonding strength during use and easy debonding on demand. Among the several block copolymers, the one consisting of poly(2-ethylhexyl methacrylate) and polyperoxide from methyl sorbate (PPMS) (M(n) = 4900) exhibited good performance as a pressure-sensitive adhesive (PSA). After heating the test specimens in a temperature range from 60 to 100 °C, PSA performance, which was evaluated by 180° peel strength and shear holding power measurements, was significantly diminished. Especially, after heating at 100 °C for 1 h, spontaneous debonding of some test specimens was observed because of the evolution of volatile acetaldehyde from PPMS.

Block 2. Photograph represents general view taken from the north/west ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Block 2. Photograph represents general view taken from the north/west region of the May D & F Tower. Photograph shows the main public gathering space for Skyline Park and depicts a light feature and an “Information” sign - Skyline Park, 1500-1800 Arapaho Street, Denver, Denver County, CO

Detail of stairway and main entrance on west front of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of stairway and main entrance on west front of center block, showing steps and frame canopy. View to southeast. - Southern Ute Boarding School, Boy's Dormitory, Ouray & Capote Drives, Ignacio, La Plata County, CO

12. Interior view of main cabin showing stairs to loft ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Interior view of main cabin showing stairs to loft area, note construction of balcony and roof - Dean E. Call Property, Big Springs Summer Home Area, Lot 5, Block D, Island Park, Fremont County, ID

The rapid cooling of the Nansha Block, southern South China Sea

NASA Astrophysics Data System (ADS)

Dong, M.; Zhang, J.

2017-12-01

Since the Late Cretaceous and Cenozoic, the Nansha Block has experienced a series of tectonic process and separated from South China continent to the south. As an exotic micro-continental, Nansha Block has an obvious different lithospheric rheology property from surrounding region. The lithosphere and mantle dynamic and rheology are mainly controlled by temperature. Therefore, we calculated the 3D temperature field and geothermal gradient of Nansha Block's upper mantle by using the S-wave velocity structure from surface wave tomography. The results show that the depth where temperature of 1300° as the lithospheric thickness is in close correspondence with the top of the seismic low velocity zone. The temperature of the upper mantle in Nansha Block is significantly lower than that of surrounding. It implies that Nansha Block experienced a rapid cooling event. We propose that the rapid cooling can be partly attributed to three reasons: 1) Nansha Block is a relatively stable block with no interior geothermal activity. 2) No external heat source to provide energy. 3) Abnormal mantle convection under Nansha Block accelerated the cooling.

Ultrasound description of Pecs II (modified Pecs I): a novel approach to breast surgery.

PubMed

Blanco, R; Fajardo, M; Parras Maldonado, T

2012-11-01

The Pecs block (pectoral nerves block) is an easy and reliable superficial block inspired by the infraclavicular block approach and the transversus abdominis plane blocks. Once the pectoralis muscles are located under the clavicle the space between the two muscles is dissected to reach the lateral pectoral and the medial pectoral nerves. The main indications are breast expanders and subpectoral prosthesis where the distension of these muscles is extremely painful. A second version of the Pecs block is described, called "modified Pecs block" or Pecs block type II. This novel approach aims to block at least the pectoral nerves, the intercostobrachial, intercostals III-IV-V-VI and the long thoracic nerve. These nerves need to be blocked to provide complete analgesia during breast surgery, and it is an alternative or a rescue block if paravertebral blocks and thoracic epidurals failed. This block has been used in our unit in the past year for the Pecs I indications described, and in addition for, tumorectomies, wide excisions, and axillary clearances. The ultrasound sequence to perform this block is shown, together with simple X-ray dye images and gadolinium MRI images to understand the spread and pathways that can explain the benefit of this novel approach. Copyright © 2012 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

some morphological effects related to a non-uniform uplifting of crustal blocks in Northern Sicily (Central Mediterranean)

NASA Astrophysics Data System (ADS)

Nigro, Fabrizio; Renda, Pietro; Favara, Rocco

2010-05-01

We can distinguish two morphological evolutions of the drainage basins which develop in the earth's sectors subjected to uplift and tilting, in relationship to their antecedence or subsequence in comparison to the tectonic process. If this process begins in concomitance with a geomorphic cycle the main valleys of the drainage basins will longitudinally be developed according to the tilting direction which the crustal block is subjected. But if the non-uniform vertical movement develops in a sector already characterized by the presence of a idrographic network, this can be influenced in its pattern in various ways. A crustal block contemporarily subject to uplift and tilting will be characterized to its inside, at the end of this process, by more elevated and less elevated sectors. The erosive ground processes suffer this non-uniform vertical movement and since it gradually develops in time, landforms, as valleys of drainage basins, will suffer analogous variations. If pre-existing, the slopes of the valleys will be subjected to tilting also and one of the characteristics in the evolution of the reliefs connected with the uplift and the tilting of crustal blocks are represented by the progressive asymmetry of the slopes of a valley. The uplift and the tilting of the block progressively determines a difference of inclination of the slopes of the incising valley. This effect is given by the progressive incision and migration of the axis of the valley that it determines slopes with crests to different middle elevation between the right side and that left. The erosional process that determines him with the uplift and the tilting of the crustal blocks are characterized by a greater erosion rate in the sectors of head of the slope that is mostly raised. Likewise, the migration of the river consistent with the tilting direction determines a greater rate of erosion along one of the banks. The general morphometric result can be that of the individualization of slopes that -in section- constitute polylines assimilable to arcs of circumference with different rays of bending. In map view, the evolution of the drainage network is characterised also from a different development of the river channels of different orders. Particularly, in the slope that is more subject to uplift the drainage network is more branched, with larger formation of river orders with respect to the opposite slope. If we suppose that the crustal block underwent to uplift and tilting is eroded from several idrographic networks that are identified in more drainage basins, at the end of the process, in absence of large-scale deformations as folding and faulting, the slope asimmetry of every main valley is maintained but, for tilting direction about orthogonal with respect to the directions of the rivers, a different altimetric development will be observed of the main rivers. If to the tilting and uplift of the crustal block are associated internal deformations as folds and faults, then the asymmetry of the slopes not always may result clearly evident, as well as the altimetric development of the main valleys. Regarding the above concepts, we recognised a non-uniform uplift and large-scale recent faulting in Northern Sicily (Central Mediterranean), both from drainage network pattern analisys, slopes geometries and structural data. The data sets have been compared with the uplift rate and seismicity distributions, allowing us to recognise different crustal blocks in which the northern Sicily chain may be divided. Each chain block reflects characteristic morphometric pattern of the drainage basins. The morphostructural setting, the distribution of seismicity and the orientation of the recent faults indicate that the main neotectonic narrow deformation zones bounding the crustal blocks range from NW-SE, NE-SW and W-E.

Modeling and prototyping of biometric systems using dataflow programming

NASA Astrophysics Data System (ADS)

Minakova, N.; Petrov, I.

2018-01-01

The development of biometric systems is one of the labor-intensive processes. Therefore, the creation and analysis of approaches and techniques is an urgent task at present. This article presents a technique of modeling and prototyping biometric systems based on dataflow programming. The technique includes three main stages: the development of functional blocks, the creation of a dataflow graph and the generation of a prototype. A specially developed software modeling environment that implements this technique is described. As an example of the use of this technique, an example of the implementation of the iris localization subsystem is demonstrated. A variant of modification of dataflow programming is suggested to solve the problem related to the undefined order of block activation. The main advantage of the presented technique is the ability to visually display and design the model of the biometric system, the rapid creation of a working prototype and the reuse of the previously developed functional blocks.

Adaptive bit plane quadtree-based block truncation coding for image compression

NASA Astrophysics Data System (ADS)

Li, Shenda; Wang, Jin; Zhu, Qing

2018-04-01

Block truncation coding (BTC) is a fast image compression technique applied in spatial domain. Traditional BTC and its variants mainly focus on reducing computational complexity for low bit rate compression, at the cost of lower quality of decoded images, especially for images with rich texture. To solve this problem, in this paper, a quadtree-based block truncation coding algorithm combined with adaptive bit plane transmission is proposed. First, the direction of edge in each block is detected using Sobel operator. For the block with minimal size, adaptive bit plane is utilized to optimize the BTC, which depends on its MSE loss encoded by absolute moment block truncation coding (AMBTC). Extensive experimental results show that our method gains 0.85 dB PSNR on average compare to some other state-of-the-art BTC variants. So it is desirable for real time image compression applications.

FBCOT: a fast block coding option for JPEG 2000

NASA Astrophysics Data System (ADS)

Taubman, David; Naman, Aous; Mathew, Reji

2017-09-01

Based on the EBCOT algorithm, JPEG 2000 finds application in many fields, including high performance scientific, geospatial and video coding applications. Beyond digital cinema, JPEG 2000 is also attractive for low-latency video communications. The main obstacle for some of these applications is the relatively high computational complexity of the block coder, especially at high bit-rates. This paper proposes a drop-in replacement for the JPEG 2000 block coding algorithm, achieving much higher encoding and decoding throughputs, with only modest loss in coding efficiency (typically < 0.5dB). The algorithm provides only limited quality/SNR scalability, but offers truly reversible transcoding to/from any standard JPEG 2000 block bit-stream. The proposed FAST block coder can be used with EBCOT's post-compression RD-optimization methodology, allowing a target compressed bit-rate to be achieved even at low latencies, leading to the name FBCOT (Fast Block Coding with Optimized Truncation).

Deconstructing Building Blocks: Preschoolers' Spatial Assembly Performance Relates to Early Mathematical Skills

ERIC Educational Resources Information Center

Verdine, Brian N.; Golinkoff, Roberta M.; Hirsh-Pasek, Kathryn; Newcombe, Nora S.; Filipowicz, Andrew T.; Chang, Alicia

2014-01-01

This study focuses on three main goals: First, 3-year-olds' spatial assembly skills are probed using interlocking block constructions (N = 102). A detailed scoring scheme provides insight into early spatial processing and offers information beyond a basic accuracy score. Second, the relation of spatial assembly to early mathematical skills…

A Late Locus of the Distractor Frequency Effect in Picture-Word Interference: Evidence from Event-Related Potentials

ERIC Educational Resources Information Center

Dhooge, Elisah; De Baene, Wouter; Hartsuiker, Robert J.

2013-01-01

In this study, we investigated how people deal with irrelevant contextual information during speech production. Two main models have been proposed. WEAVER++ assumes that irrelevant information is removed from the production system by an early blocking mechanism. On the other hand, the response exclusion hypothesis assumes a blocking mechanism that…

Atmospheric blocking in the Climate SPHINX simulations: the role of orography and resolution

NASA Astrophysics Data System (ADS)

Davini, Paolo; Corti, Susanna; D'Andrea, Fabio; Riviere, Gwendal; von Hardenberg, Jost

2017-04-01

The representation of atmospheric blocking in numerical simulations, especially over the Euro-Atlantic region, still represents a main concern for the climate modelling community. We here discuss the Northern Hemisphere winter atmospheric blocking representation in a set of 30-year simulations which has been performed in the framework of the PRACE project "Climate SPHINX". Simulations were run using the EC-Earth Global Climate Model with several ensemble members at 5 different horizontal resolutions (ranging from 125 km to 16 km). Results show that the negative bias in blocking frequency over Europe becomes negligible at resolutions of about 40 km and finer. However, the blocking duration is still underestimated by 1-2 days, suggesting that the correct blocking frequencies are achieved with an overestimation of the number of blocking onsets. The reasons leading to such improvements are then discussed, highlighting the role of orography in shaping the Atlantic jet stream: at higher resolution the jet is weaker and less penetrating over Europe, favoring the breaking of synoptic Rossby waves over the Atlantic stationary ridge and thus increasing the simulated blocking frequency.

On optimizing the blocking step of indirect enzyme-linked immunosorbent assay for Epstein-Barr virus serology.

PubMed

Lim, Chun Shen; Krishnan, Gopala; Sam, Choon Kook; Ng, Ching Ching

2013-01-16

Because blocking agent occupies most binding surface of a solid phase, its ability to prevent nonspecific binding determines the signal-to-noise ratio (SNR) and reliability of an enzyme-linked immunosorbent assay (ELISA). We demonstrate a stepwise approach to seek a compatible blocking buffer for indirect ELISA, via a case-control study (n=176) of Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC). Regardless of case-control status, we found that synthetic polymer blocking agents, mainly Ficoll and poly(vinyl alcohol) (PVA) were able to provide homogeneous backgrounds among samples, as opposed to commonly used blocking agents, notably nonfat dry milk (NFDM). The SNRs for NPC samples that correspond to blocking using PVA were approximately 3-fold, on average, higher than those blocking using NFDM. Both intra- and inter-assay precisions of PVA-based assays were <14%. A blocking agent of choice should have tolerable sample backgrounds from both cases and controls to ensure the reliability of an immunoassay. Copyright © 2012 Elsevier B.V. All rights reserved.

Neurostimulation in ultrasound-guided infraclavicular block: a prospective randomized trial.

PubMed

Dingemans, Emmanuel; Williams, Stephan R; Arcand, Geneviève; Chouinard, Philippe; Harris, Patrick; Ruel, Monique; Girard, François

2007-05-01

Ultrasound guidance (USG) for infraclavicular blocks provides real time visualization of the advancing needle and local anesthetic distribution. Whether visualization of local anesthetic spread can supplant neurostimulation as the end point for local anesthetic injection during USG block has never been formally evaluated. Therefore, for this prospective randomized study, we recruited 72 patients scheduled for hand or forearm surgery and compared the speed of execution and quality of USG infraclavicular block with either USG alone (Group U) or USG combined with neurostimulation (Group S). In Group U, local anesthetic was deposited in a U-shaped distribution posterior and to each side of the axillary artery using as few injections as possible (1, 2, and 3 injections in 29, 6, and 3 patients, respectively). In Group S, a single injection was made after obtaining a distal motor response with a stimulating current between 0.3 and 0.6 mA. The anesthetic solution consisted of 0.5 mL/kg of lidocaine 1.5%, bupivacaine 0.125%, and epinephrine 1:200 000 (final concentrations). Procedure times were significantly shorter in Group U compared with Group S (3.1 +/- 1.6 min and 5.2 +/- 4.7 min, respectively; P = 0.006). In Group S, anesthetic spread was mainly anterior to the axillary artery in 37% of patients and mainly posterior in 63% of patients. Thirty minutes after the injection, 86% of patients in Group U had complete sensory block in the musculocutaneous, median, radial, and ulnar nerve territories compared with 57% in Group S (P = 0.007). Patients blocked in Group U with a single injection had the same rate of complete block (86%) as those blocked with more than one injection (86%). Block supplementation rates were 8% in Group U versus 26% in Group S (P = 0.049). Block failure occurred in one patient in Group S because of an inability to obtain a distal stimulation after 20 min. We conclude that USG infraclavicular block is more rapidly performed and yields a higher success rate when visualization of local anesthetic spread is used as the end point for injection. Posterolateral spread of local anesthetic around the axillary artery predicts successful block, circumventing the need for direct nerve visualization.

Understanding and controlling morphology formation in Langmuir-Blodgett block copolymer films using PS-P4VP and PS-P4VP/PDP.

PubMed

Perepichka, Iryna I; Lu, Qing; Badia, Antonella; Bazuin, C Geraldine

2013-04-09

This contribution offers a comprehensive understanding of the factors that govern the morphologies of Langmuir-Blodgett (LB) monolayers of amphiphilic diblock copolymers (BCs). This is achieved by a detailed investigation of a wide range of polystyrene-poly(4-vinyl pyridine) (PS-P4VP) block copolymers, in contrast to much more limited ranges in previous studies. Parameters that are varied include the block ratios (mainly for similar total molecular weights, occasionally other total molecular weights), the presence or not of 3-n-pentadecylphenol (PDP, usually equimolar with VP, with which it hydrogen bonds), the spreading solution concentration ("low" and "high"), and the LB technique (standard vs "solvent-assisted"). Our observations are compared with previously published results on other amphiphilic diblock copolymers, which had given rise to contradictory interpretations of morphology formation. Based on the accumulated results, we re-establish early literature conclusions that three main categories of LB block copolymer morphologies are obtained depending on the block ratio, termed planar, strand, and dot regimes. The block composition boundaries in terms of mol % block content are shown to be similar for all BCs having alkyl chain substituents on the hydrophilic block (such as PS-P4VP/PDP) and are shifted to higher values for BCs with no alkyl chain substituents (such as PS-P4VP). This is attributed to the higher surface area per repeat unit of the hydrophilic block monolayer on the water surface for the former, as supported by the onset and limiting areas of the Langmuir isotherms for the BCs in the dot regime. 2D phase diagrams are discussed in terms of relative effective surface areas of the two blocks. We identify and discuss how kinetic effects on morphology formation, which have been highlighted in more recent literature, are superposed on the compositional effects. The kinetic effects are shown to depend on the morphology regime, most strongly influencing the strand and, especially, planar regimes, where they give rise to a diversity of specific structures. Besides film dewetting mechanisms, which are different when occurring in structured versus unstructured films (the latter previously discussed in the literature), kinetic influences are discussed in terms of chain association dynamics leading to depletion effects that impact on growing aggregates. These depletion effects particularly manifest themselves in more dilute spreading solutions, with higher molecular weight polymers, and in composition regimes characterized by equilibrium degrees of aggregation that are effectively infinite. It is by understanding these various kinetic influences that the diversity of structures can be classified by the three main composition-dependent regimes.

8. PARK AVENUE EAST OF CEDAR STREET (400 Block). THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. PARK AVENUE EAST OF CEDAR STREET (400 Block). THE MARCHION HARDWARE BUILDING WAS DESIGNED BY W.W. HISLOP, AND BUILT IN 1895. THE GROUND FLOOR WAS RENOVATED SOME TIME IN THE 1930s. IN THE CENTER IS THE IMPERIAL BLOCK (ca. 1920), AND THE FULLER DRUG COMPANY (1918-1932).THE FULLER SITE WAS OCCUPIED BY THE HIGHLAND THEATER FROM 1932 TO 1972, AND RETAINS MUCH OF THE INTERIOR DECORATION FROM THAT PERIOD - Anaconda Historic District, Park & Commercial Streets, Main Street vicinity, Anaconda, Deer Lodge County, MT

Properties of Fly Ash Blocks Made from Adobe Mould

NASA Astrophysics Data System (ADS)

Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-02-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

Properties of Fly Ash Blocks Made from Adobe Mould

NASA Astrophysics Data System (ADS)

Chokhani, Alankrit; Divakar, B. S.; Jawalgi, Archana S.; Renukadevi, M. V.; Jagadish, K. S.

2018-06-01

Fly ash being one of the industrial waste products poses a serious disposal problem. This paper presents an experimental study of utilization of fly ash to produce blocks with varying proportions and mix combinations. Composition of fly ash blocks mainly consist of fly ash and sand, with cementitious product as either cement, lime or both, such as fly ash-sand-cement, fly ash-sand-lime and fly ash-sand-cement-lime are used. Four different proportions for each of the mix combinations are experimented. Compressive strength, water absorption, Initial rate of absorption, and dry density of fly ash blocks are studied. The influence of partial and complete replacement of cement by lime is examined.

Geological-morphological description of the Ishtar Terra (photomap of the Venusian surface sheet B-5)

NASA Technical Reports Server (NTRS)

Sukhanov, A. L.; Pronin, A. A.; Tyuflin, Y. S.; Ostrovskiy, M. V.; Kotelnikov, V. A.; Rzhiga, O. N.; Petrov, G. I.; Sidorenko, A. I.; Aleksandrov, Y. N.; Zakharov, A. I.

1986-01-01

The main part of the Ishtar Terra east of the Maxwell Montes is covered with systems of areal dislocations of several directions, which are called Parquet. According to the structural patterns these may be divided into: (1) the central stable block; (2) the lesser peripheral blocks separated from the central one by gaps and grabens; (3) the zones of mobilized parquet, whose substance flowed downward at an incline in the directions away from the central block in the form of plastic flows; and (4) the partially parqueted lava sheets. The Maxwell Montes were formed as a result of the collision between the central parquet block and the Lakshmi Planum.

The Mobile Margin of (Far) North America: GPS Constraints on Active Deformation in Alaska and the Role of the Yakutat Block

NASA Astrophysics Data System (ADS)

Elliott, J.; Freymueller, J. T.; Larsen, C. F.; Motyka, R. J.

2010-12-01

GPS data from southern Alaska and the northern Canadian Cordillera have helped redefine the region’s tectonic landscape. Instead of a comparatively simple interaction between the Pacific and North American plates, with relative motion accommodated on a single boundary fault, we find a margin made up of a number of small blocks and deformation zones with relative motion distributed across a variety of structures. Much of this complexity can be attributed to the Yakutat block, an allochthonous terrane that has been colliding with southern Alaska since the Miocene. We present a GPS-derived tectonic model for the Yakutat block collision and its effects on southern Alaska and eastern Canada. The Yakutat block moves NNW at a rate of 50 mm/a, resulting in ~ 45 mm/a of NW-directed convergence with southern Alaska. Along its eastern edge, the Yakutat block is deforming, represented in our model by two small northwesterly moving blocks outboard of the Fairweather fault. Part of the strain from the collision is transferred east of the Fairweather - Queen Charlotte fault system, causing the region inboard of the Fairweather fault to undergo a distinct clockwise rotation into the northern Canadian Cordillera. Further south, the region directly east of the Queen Charlotte fault displays a much slower clockwise rotation, suggesting that it is at least partially pulled along by the northern block motion. About 5% of the relative motion is transferred even further east, causing small northeasterly motions well into the northern Cordillera. The northwestern edge of the Yakutat block marks the main deformation front between that block and southern Alaska. Multiple narrow, northwesterly moving blocks bounded by N- to NW-dipping thrust faults are required to explain the GPS data between the Malaspina Glacier and the Bagley Ice Valley. These “blocks” may be more aptly termed crustal slivers or deformation zones due to their size and because their bounding faults may sole out into a main thrust instead of cutting through the lithosphere. In contrast with the region to the east, relative convergence is accommodated over a fairly short distance across the St. Elias Mountains. West of the deformation front, the en echelon blocks and faults continue until the vicinity of the Bering Glacier, where the GPS data reveal a rotation towards the north as the tectonic regime transitions from the collision and accretion of the Yakutat block to subduction along the Aleutian Megathrust. North of the Chugach and St. Elias Ranges, the Southern Alaska block rotates counterclockwise.

Failure Analysis of Overhanging Blocks in the Walls of a Gas Storage Salt Cavern: A Case Study

NASA Astrophysics Data System (ADS)

Wang, Tongtao; Yang, Chunhe; Li, Jianjun; Li, Jinlong; Shi, Xilin; Ma, Hongling

2017-01-01

Most of the rock salt of China is bedded, in which non-salt layers and rock salt layers alternate. Due to the poor solubility of the non-salt layers, many blocks overhang on the walls of the caverns used for gas storage, constructed by water leaching. These overhanging blocks may collapse at any time, which may damage the tubing and casing string, and even cause instability of the cavern. They are one of the main factors threatening the safety of caverns excavated in bedded rock salt formations. In this paper, a geomechanical model of the JJKK-D salt cavern, located in Jintan salt district, Jintan city, Jiangsu province, China, is established to evaluate the stability of the overhanging blocks on its walls. The characters of the target formation, property parameters of the rock mass, and actual working conditions are considered in the geomechanical model. An index system composed of stress, displacement, plastic zone, safety factor, and equivalent strain is used to predict the collapse length of the overhanging blocks, the moment the collapse will take place, and the main factors causing the collapse. The sonar survey data of the JJKK-D salt cavern are used to verify the reliability and accuracy of the proposed geomechanical model. The results show that the proposed geomechanical model has a good reliability and accuracy, and can be used for the collapse prediction of the overhanging blocks on the wall of the JJKK-D salt cavern. The collapse length of the overhanging block is about 8 m. We conclude that the collapse takes place during the debrining. The reason behind the collapse is the sudden decrease of the fluid density, leading to the increase of the self-weight of the overhanging blocks. This study provides a basis for the collapse prediction method of the overhanging blocks of Jintan salt cavern gas storage, and can also serve as a reference for salt cavern gas storage with similar conditions to deal with overhanging blocks.

How Properties of Kenaf Fibers from Burkina Faso Contribute to the Reinforcement of Earth Blocks

PubMed Central

Millogo, Younoussa; Aubert, Jean-Emmanuel; Hamard, Erwan; Morel, Jean-Claude

2015-01-01

Physicochemical characteristics of Hibiscus cannabinus (kenaf) fibers from Burkina Faso were studied using X-ray diffraction (XRD), infrared spectroscopy, thermal gravimetric analysis (TGA), chemical analysis and video microscopy. Kenaf fibers (3 cm long) were used to reinforce earth blocks, and the mechanical properties of reinforced blocks, with fiber contents ranging from 0.2 to 0.8 wt%, were investigated. The fibers were mainly composed of cellulose type I (70.4 wt%), hemicelluloses (18.9 wt%) and lignin (3 wt%) and were characterized by high tensile strength (1 ± 0.25 GPa) and Young’s modulus (136 ± 25 GPa), linked to their high cellulose content. The incorporation of short fibers of kenaf reduced the propagation of cracks in the blocks, through the good adherence of fibers to the clay matrix, and therefore improved their mechanical properties. Fiber incorporation was particularly beneficial for the bending strength of earth blocks because it reinforces these blocks after the failure of soil matrix observed for unreinforced blocks. Blocks reinforced with such fibers had a ductile tensile behavior that made them better building materials for masonry structures than unreinforced blocks.

The Voyage of a Navigator An aspiring scholar's inside observations on the Affordable Care Act's rocky roll-out in North Carolina.

PubMed

Tripp, Hollie L

2015-01-01

North Carolina, a federally facilitated marketplace under the Affordable Care Act (ACA), stumbled in 2013 when opening its health-insurance exchange. Trouble was easy to foresee, as North Carolina had instituted a law barring any state agency from assisting enrollment in health-insurance plans made available through the ACA. Trained workers were needed to help citizens and legal immigrants "navigate" to these plans. Some of these "navigators" could be paid with federal funds, but many others had to work as volunteers. I was one of these volunteer navigators. Much went wrong in training, staffing, and operations, but much still was accomplished. Here I report observations, share assessments, and offer suggestions for similarly complex situations.

Interlocking wettable ceramic tiles

DOEpatents

Tabereaux, Jr., Alton T.; Fredrickson, Guy L.; Groat, Eric; Mroz, Thomas; Ulicny, Alan; Walker, Mark F.

2005-03-08

An electrolytic cell for the reduction of aluminum having a layer of interlocking cathode tiles positioned on a cathode block. Each tile includes a main body and a vertical restraining member to prevent movement of the tiles away from the cathode block during operation of the cell. The anode of the electrolytic cell may be positioned about 1 inch from the interlocking cathode tiles.

The shaping of human diversity: filters, boundaries and transitions

PubMed Central

Mirazón Lahr, Marta

2016-01-01

The evolution of modern humans was a complex process, involving major changes in levels of diversity through time. The fossils and stone tools that record the spatial distribution of our species in the past form the backbone of our evolutionary history, and one that allows us to explore the different processes—cultural and biological—that acted to shape the evolution of different populations in the face of major climate change. Those processes created a complex palimpsest of similarities and differences, with outcomes that were at times accelerated by sharp demographic and geographical fluctuations. The result is that the population ancestral to all modern humans did not look or behave like people alive today. This has generated questions regarding the evolution of human universal characters, as well as the nature and timing of major evolutionary events in the history of Homo sapiens. The paucity of African fossils remains a serious stumbling block for exploring some of these issues. However, fossil and archaeological discoveries increasingly clarify important aspects of our past, while breakthroughs from genomics and palaeogenomics have revealed aspects of the demography of Late Quaternary Eurasian hominin groups and their interactions, as well as those between foragers and farmers. This paper explores the nature and timing of key moments in the evolution of human diversity, moments in which population collapse followed by differential expansion of groups set the conditions for transitional periods. Five transitions are identified (i) at the origins of the species, 240–200 ka; (ii) at the time of the first major expansions, 130–100 ka; (iii) during a period of dispersals, 70–50 ka; (iv) across a phase of local/regional structuring of diversity, 45–25 ka; and (v) during a phase of significant extinction of hunter–gatherer diversity and expansion of particular groups, such as farmers and later societies (the Holocene Filter), 15–0 ka. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298471

Familiarity of Alpine magnitude and geometry as a critical pedagogic element in student visualisation of basin- & crustal-scale sub-surface structure

NASA Astrophysics Data System (ADS)

Edwards, M. A.

2004-12-01

A geoscience education stumbling block that typically re-currs throughout the early years of student progress is bringing three dimensional spatial scales of Earth's features in perspective. This far more so than temporal scales; the concept of geological timescale is normally quickly adopted into a students perception. Providing a sense of proportion for three dimensional objects is two fold: the first, the actual "thinking in 3D" while often depicting in 2D (e.g. seismic moment "beachballs", stereonets, cross-sections, atmospheric circulation cells) has been dramatically assisted by accelerated graphics imaging software. The second, proportion across all scales, is subtle yet crucial and not necessarily better-conveyed to students exclusively via computer-assisted learning. My experiences teaching students from a range of geographical backgrounds strongly indicates a much firmer grasp overall, by students from Alpine regions, of magnitudes and scales of crustal features. The intensity of topography in these regions, where cablecar and steep walking are the primary accesses, is a unique opportunity to illustrate the km-scale of structures in 3D, a lesson far beyond one of simply illustrating the appearance of typical rocks "in the great outdoors" and very tricky to convery through "virtual" field trips alone. Examples include; 1. the embodiment of a shallow seismic reflection profile to a several hundrend metre cliff of intercalated (i.e. switching impedance contrast) turbidites whose km-long overthrust line is traceable along a valley floor far below. 2. the weight of the thrust pile underfoot and corresponding amounts of lithosphere bending and foreland basin growth - a perspective often lost with beam engineering-only approaches. 3. fluid-volumes: intensely solution-strained &/or vein-bearing masses can be estimated for volume percentage and total cubic amount across a mountain region. 4. instantaneous river bedload versus yearly versus m.y. total volumes. Such 3D realism is crucial is subsurface modelling of hydrocarbon/water/waste potentials.

Space micropropulsion systems for Cubesats and small satellites: From proximate targets to furthermost frontiers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levchenko, Igor; Bazaka, Kateryna; Ding, Yongjie

Rapid evolution of miniaturized, automatic, robotized, function-centered devices has redefined space technology, bringing closer the realization of most ambitious interplanetary missions and intense near-Earth space exploration. Small unmanned satellites and probes are now being launched in hundreds at a time, resurrecting a dream of satellite constellations, i.e., wide, all-covering networks of small satellites capable of forming universal multifunctional, intelligent platforms for global communication, navigation, ubiquitous data mining, Earth observation, and many other functions, which was once doomed by the extraordinary cost of such systems. The ingression of novel nanostructured materials provided a solid base that enabled the advancement of thesemore » affordable systems in aspects of power, instrumentation, and communication. However, absence of efficient and reliable thrust systems with the capacity to support precise maneuvering of small satellites and CubeSats over long periods of deployment remains a real stumbling block both for the deployment of large satellite systems and for further exploration of deep space using a new generation of spacecraft. The last few years have seen tremendous global efforts to develop various miniaturized space thrusters, with great success stories. Yet, there are critical challenges that still face the space technology. These have been outlined at an inaugural International Workshop on Micropropulsion and Cubesats, MPCS-2017, a joint effort between Plasma Sources and Application Centre/Space Propulsion Centre (Singapore) and the Micropropulsion and Nanotechnology Lab, the G. Washington University (USA) devoted to miniaturized space propulsion systems, and hosted by CNR-Nanotec—P.Las.M.I. lab in Bari, Italy. This focused review aims to highlight the most promising developments reported at MPCS-2017 by leading world-reputed experts in miniaturized space propulsion systems. Recent advances in several major types of small thrusters including Hall thrusters, ion engines, helicon, and vacuum arc devices are presented, and trends and perspectives are outlined.« less

Space micropropulsion systems for Cubesats and small satellites: From proximate targets to furthermost frontiers

DOE PAGES

Levchenko, Igor; Bazaka, Kateryna; Ding, Yongjie; ...

2018-02-22

Rapid evolution of miniaturized, automatic, robotized, function-centered devices has redefined space technology, bringing closer the realization of most ambitious interplanetary missions and intense near-Earth space exploration. Small unmanned satellites and probes are now being launched in hundreds at a time, resurrecting a dream of satellite constellations, i.e., wide, all-covering networks of small satellites capable of forming universal multifunctional, intelligent platforms for global communication, navigation, ubiquitous data mining, Earth observation, and many other functions, which was once doomed by the extraordinary cost of such systems. The ingression of novel nanostructured materials provided a solid base that enabled the advancement of thesemore » affordable systems in aspects of power, instrumentation, and communication. However, absence of efficient and reliable thrust systems with the capacity to support precise maneuvering of small satellites and CubeSats over long periods of deployment remains a real stumbling block both for the deployment of large satellite systems and for further exploration of deep space using a new generation of spacecraft. The last few years have seen tremendous global efforts to develop various miniaturized space thrusters, with great success stories. Yet, there are critical challenges that still face the space technology. These have been outlined at an inaugural International Workshop on Micropropulsion and Cubesats, MPCS-2017, a joint effort between Plasma Sources and Application Centre/Space Propulsion Centre (Singapore) and the Micropropulsion and Nanotechnology Lab, the G. Washington University (USA) devoted to miniaturized space propulsion systems, and hosted by CNR-Nanotec—P.Las.M.I. lab in Bari, Italy. This focused review aims to highlight the most promising developments reported at MPCS-2017 by leading world-reputed experts in miniaturized space propulsion systems. Recent advances in several major types of small thrusters including Hall thrusters, ion engines, helicon, and vacuum arc devices are presented, and trends and perspectives are outlined.« less

Family veto in organ donation in Canada: framing within English-language newspaper articles.

PubMed

Anthony, Samantha J; Toews, Maeghan; Caulfield, Timothy; Wright, Linda

2017-10-17

Because organ transplantation relies on public support for donation, an analysis of public discourse around organ donation is essential. We investigated the portrayal of family veto - when a family overrides the deceased person's prior legally executed wishes to donate - in Canadian news media. Using the Canadian Newsstream database, we identified articles published in English-language newspapers addressing family veto between 2000 and 2016. Guided by the theoretical perspectives of framing of media effects, we conducted a systematic content analysis of the articles to examine how the Canadian media framed family veto. An initial in-depth analysis of the data set in which themes and patterns were captured and recorded identified coding categories, including primary framing of family veto, prevalence, reasons, ethical or legal concerns and overall tone of the article. Two coders analyzed the data set to ensure intercoder reliability. A total of 133 relevant articles were identified. Family veto was framed predominantly as something that should not be allowed (81 articles [60.9%]) and as a reality that is little understood outside the transplantation community (45 [33.8%]). One-quarter of the articles (32 [24.1%]) highlighted ethical principles of autonomy and justice associated with family veto. Family veto was represented as a stumbling block in the present organ donation system, with most publications (107 [80.4%]) calling for change. There were differing interpretations of organ donation legislation, with 82 articles (61.6%) erroneously stating or suggesting that existing legislation permits family veto. Family veto in organ donation was portrayed predominantly negatively. Many publications reflected a misunderstanding of the law concerning this issue. Although the framing of family veto highlighted important ethical and legal concerns as well as practice and policy considerations, research is needed to enhance the understanding of family veto in organ donation. Copyright 2017, Joule Inc. or its licensors.

Multifunctional pH-Sensitive Amino Lipids for siRNA Delivery.

PubMed

Gujrati, Maneesh; Vaidya, Amita; Lu, Zheng-Rong

2016-01-20

RNA interference (RNAi) represents a powerful modality for human disease therapy that can regulate gene expression signature using small interfering RNA (siRNA). Successful delivery of siRNA into the cytoplasm of target cells is imperative for efficient RNAi and also constitutes the primary stumbling block in the clinical applicability of RNAi. Significant progress has been made in the development of lipid-based siRNA delivery systems, which have practical advantages like simple chemistry and easy formulation of nanoparticles with siRNA. This review discusses the recent development of pH-sensitive amino lipids, with particular focus on multifunctional pH-sensitive amino lipids for siRNA delivery. The key components of these multifunctional lipids include a protonatable amino head group, distal lipid tails, and two cross-linkable thiol groups, which together facilitate the facile formation of stable siRNA-nanoparticles, easy surface modification for target-specific delivery, endosomal escape in response to the pH decrease during subcellular trafficking, and reductive dissociation of the siRNA-nanoparticles for cytoplasmic release of free siRNA. By virtue of these properties, multifunctional pH-sensitive lipids can mediate efficient cytosolic siRNA delivery and gene silencing. Targeted siRNA nanoparticles can be readily formulated with these lipids, without the need for other helper lipids, to promote systemic delivery of therapeutic siRNAs. Such targeted siRNA nanoparticles have been shown to effectively regulate the expression of cancer-related genes, resulting in significant efficacy in the treatment of aggressive tumors, including metastatic triple negative breast cancer. These multifunctional pH-sensitive lipids constitute a promising platform for the systemic and targeted delivery of therapeutic siRNA for the treatment of human diseases. This review summarizes the structure-property relationship of the multifunctional pH-sensitive lipids and their efficacy in in vitro and in vivo siRNA delivery and gene silencing.

Comparison of modification strategies towards enhanced charge carrier separation and photocatalytic degradation activity of metal oxide semiconductors (TiO2, WO3 and ZnO)

NASA Astrophysics Data System (ADS)

Kumar, S. Girish; Rao, K. S. R. Koteswara

2017-01-01

Metal oxide semiconductors (TiO2, WO3 and ZnO) finds unparalleled opportunity in wastewater purification under UV/visible light, largely encouraged by their divergent admirable features like stability, non-toxicity, ease of preparation, suitable band edge positions and facile generation of active oxygen species in the aqueous medium. However, the perennial failings of these photocatalysts emanates from the stumbling blocks like rapid charge carrier recombination and meager visible light response. In this review, tailoring the surface-bulk electronic structure through the calibrated and veritable approaches such as impurity doping, deposition with noble metals, sensitizing with other compounds (dyes, polymers, inorganic complexes and simple chelating ligands), hydrogenation process (annealing under hydrogen atmosphere), electronic integration with other semiconductors, modifying with carbon nanostructures, designing with exposed facets and tailoring with hierarchical morphologies to overcome their critical drawbacks are summarized. Taking into account the materials intrinsic properties, the pros and cons together with similarities and striking differences for each strategy in specific to TiO2, WO3 & ZnO are highlighted. These subtlety enunciates the primacy for improving the structure-electronic properties of metal oxides and credence to its fore in the practical applications. Future research must focus on comparing the performances of ZnO, TiO2 and WO3 in parallel to get insight into their photocatalytic behaviors. Such comparisons not only reveal the changed surface-electronic structure upon various modifications, but also shed light on charge carrier dynamics, free radical generation, structural stability and compatibility for photocatalytic reactions. It is envisioned that these cardinal tactics have profound implications and can be replicated to other semiconductor photocatalysts like CeO2, In2O3, Bi2O3, Fe2O3, BiVO4, AgX, BiOX (X = Cl, Br & I), Bi2WO6, Bi2MoO6, etc., to improve their competence for various environmental applications.

The experiences and challenges faced by rehabilitation community service therapists within the South African Primary Healthcare health system

PubMed Central

2017-01-01

Background Twenty-two years after the promulgation of a plethora of progressive health policies since 1994, the South African public health system reflects a number of stumbling blocks regarding implementation. Rehabilitation professionals are not sufficiently equipped nor allowed the opportunity to comprehensively implement Primary Healthcare (PHC) from a bottom-up approach, thus engaging communities. Training on addressing social health determinants and their impact on ill-health and health outcomes is inadequate. The inadequate understanding of the advocacy role that rehabilitation professionals could play in addressing social health determinants remains a challenge in healthcare. Rehabilitation, a pillar of PHC, remains poorly understood in terms of its role within the health system. Aim We argue for rehabilitation as a vehicle for addressing social determinants of health with community service practitioners playing a critical role in addressing the inequities within the healthcare package. Setting The article reflects the opportunities and challenges faced by rehabilitation community service therapists in the delivery of rehabilitation services in a rural area of the Eastern Cape province of South Africa. Methods A single case study from the perspective of a researcher was used to explore the experience and reflection of the first author during her community service as an occupational therapist. Results The case study highlights some existing gaps within the delivery of rehabilitation services in the rural Eastern Cape. A community service package with a specific approach towards addressing social determinants of health for persons with disability at a community level is suggested. Conclusion Advocating for a rehabilitation service package to shift to community-based levels is critical. It is envisaged that a community-based approach will facilitate an understanding of the barriers faced by persons with disabilities as constituting disability, thus facilitating learning about the disabling consequences of the rural environment coupled with the system as experienced by persons with disabilities. PMID:29062760

CILogon: An Integrated Identity and Access Management Platform for Science

NASA Astrophysics Data System (ADS)

Basney, J.

2016-12-01

When scientists work together, they use web sites and other software to share their ideas and data. To ensure the integrity of their work, these systems require the scientists to log in and verify that they are part of the team working on a particular science problem. Too often, the identity and access verification process is a stumbling block for the scientists. Scientific research projects are forced to invest time and effort into developing and supporting Identity and Access Management (IAM) services, distracting them from the core goals of their research collaboration. CILogon provides an IAM platform that enables scientists to work together to meet their IAM needs more effectively so they can allocate more time and effort to their core mission of scientific research. The CILogon platform enables federated identity management and collaborative organization management. Federated identity management enables researchers to use their home organization identities to access cyberinfrastructure, rather than requiring yet another username and password to log on. Collaborative organization management enables research projects to define user groups for authorization to collaboration platforms (e.g., wikis, mailing lists, and domain applications). CILogon's IAM platform serves the unique needs of research collaborations, namely the need to dynamically form collaboration groups across organizations and countries, sharing access to data, instruments, compute clusters, and other resources to enable scientific discovery. CILogon provides a software-as-a-service platform to ease integration with cyberinfrastructure, while making all software components publicly available under open source licenses to enable re-use. Figure 1 illustrates the components and interfaces of this platform. CILogon has been operational since 2010 and has been used by over 7,000 researchers from more than 170 identity providers to access cyberinfrastructure including Globus, LIGO, Open Science Grid, SeedMe, and XSEDE. The "CILogon 2.0" platform, launched in 2016, adds support for virtual organization (VO) membership management, identity linking, international collaborations, and standard integration protocols, through integration with the Internet2 COmanage collaboration software.

Women in medicine: still a long way to go, baby.

PubMed

Williams, B

1999-09-01

No doubt about it, women have come a long way in the medical profession. The average female enrollment in our nation's medical schools is 42% and growing. Women physicians are entering more non-traditional fields and are running successful practices. They're working to change attitudes and overcome obstacles that have traditionally barred them from thriving in such a demanding field. They're getting creative with options that allow them to pursue their dream while raising a family. But the bars are still up on some windows, namely the ones that peek into the halls of organized medicine. Professional organizations and medical schools are still largely run by men. The Tennessee Medical Association recognizes the discrepancy and is working to make some changes. TMA's Executive Assistant for Membership Services Phyllis Franklin says leadership is rethinking the entire structure of the Association in the light of changing demographics. "We're looking at younger physicians, minorities, female physicians, academicians, and students; we want to get them involved in organized medicine," she says. The leadership structure is one area that is slowly changing. Franklin admits while the hierarchy has been male-dominated, the Association can now claim its first female vice president, Dr. Phyllis Miller of Chattanooga. "We don't have a lot of women leaders, but it's getting better, and there are a lot more opportunities in the committee structure." TMA officials say surveys are forthcoming that will help them gauge the needs and wants of its female membership and hopefully increase further that 11% number, up from 8.9% two years ago. In the meantime, Franklin encourages women physicians to make their wishes known. "Instead of not joining the TMA because of perceived barriers or stumbling blocks, we would certainly prefer that they help us identify obstacles and give us the opportunity to do what we can to make membership more appealing," she says. "This Association is truly for all physicians."

Open exchange of scientific knowledge and European copyright: The case of biodiversity information

PubMed Central

Egloff, Willi; Patterson, David J.; Agosti, Donat; Hagedorn, Gregor

2014-01-01

Abstract Background. The 7th Framework Programme for Research and Technological Development is helping the European Union to prepare for an integrative system for intelligent management of biodiversity knowledge. The infrastructure that is envisaged and that will be further developed within the Programme “Horizon 2020” aims to provide open and free access to taxonomic information to anyone with a requirement for biodiversity data, without the need for individual consent of other persons or institutions. Open and free access to information will foster the re-use and improve the quality of data, will accelerate research, and will promote new types of research. Progress towards the goal of free and open access to content is hampered by numerous technical, economic, sociological, legal, and other factors. The present article addresses barriers to the open exchange of biodiversity knowledge that arise from European laws, in particular European legislation on copyright and database protection rights. We present a legal point of view as to what will be needed to bring distributed information together and facilitate its re-use by data mining, integration into semantic knowledge systems, and similar techniques. We address exceptions and limitations of copyright or database protection within Europe, and we point to the importance of data use agreements. We illustrate how exceptions and limitations have been transformed into national legislations within some European states to create inconsistencies that impede access to biodiversity information. Conclusions. The legal situation within the EU is unsatisfactory because there are inconsistencies among states that hamper the deployment of an open biodiversity knowledge management system. Scientists within the EU who work with copyright protected works or with protected databases have to be aware of regulations that vary from country to country. This is a major stumbling block to international collaboration and is an impediment to the open exchange of biodiversity knowledge. Such differences should be removed by unifying exceptions and limitations for research purposes in a binding, Europe-wide regulation. PMID:25009418

ROBO1, a tumor suppressor and critical molecular barrier for localized tumor cells to acquire invasive phenotype: Study in African-American and Caucasian prostate cancer models

PubMed Central

Parray, Aijaz; Siddique, Hifzur R.; Kuriger, Jacquelyn K.; Mishra, Shrawan K.; Rhim, Johng S.; Nelson, Heather H.; Aburatani, Hiroyuki; Konety, Badrinath R.; Koochekpour, Shahriar; Saleem, Mohammad

2015-01-01

High-risk populations exhibit early transformation of localized prostate cancer (CaP) disease to metastasis which results in the mortality of such patients. The paucity of knowledge about the molecular mechanism involved in acquiring of metastatic behavior by primary tumor cells and non-availability of reliable phenotype-discriminating biomarkers are stumbling blocks in the management of CaP disease. Here, we determine the role and translational relevance of ROBO1 (an organogenesis-associated gene) in human CaP. Employing CaP-progression models and prostatic tissues of Caucasian and African-American patients, we show that ROBO1 expression is localized to cell-membrane and significantly lost in primary and metastatic tumors. While Caucasians exhibited similar ROBO1 levels in primary and metastatic phenotype, a significant difference was observed between tumor phenotypes in African-Americans. Epigenetic assays identified promoter methylation of ROBO1 specific to African-American metastatic CaP cells. Using African-American CaP models for further studies, we show that ROBO1 negatively regulates motility and invasiveness of primary CaP cells, and its loss causes these cells to acquire invasive trait. To understand the underlying mechanism, we employed ROBO1-expressing/ROBO1-C2C3-mutant constructs, immunoprecipitation, confocal-microscopy and luciferase-reporter techniques. We show that ROBO1 through its interaction with DOCK1 (at SH3-SH2-domain) controls the Rac-activation. However, loss of ROBO1 results in Rac1-activation which in turn causes E-Cadherin/β-catenin cytoskeleton destabilization and induction of cell migration. We suggest that ROBO1 is a predictive biomarker that has potential to discriminate among CaP types, and could be exploited as a molecular target to inhibit the progression of disease as well as treat metastasis in high-risk populations such as African-Americans. PMID:24752651

Untangling the Relatedness among Correlations, Part II: Inter-Subject Correlation Group Analysis through Linear Mixed-Effects Modeling

PubMed Central

Chen, Gang; Taylor, Paul A.; Shin, Yong-Wook; Reynolds, Richard C.; Cox, Robert W.

2016-01-01

It has been argued that naturalistic conditions in FMRI studies provide a useful paradigm for investigating perception and cognition through a synchronization measure, inter-subject correlation (ISC). However, one analytical stumbling block has been the fact that the ISC values associated with each single subject are not independent, and our previous paper (Chen et al., 2016) used simulations and analyses of real data to show that the methodologies adopted in the literature do not have the proper control for false positives. In the same paper, we proposed nonparametric subject-wise bootstrapping and permutation testing techniques for one and two groups, respectively, which account for the correlation structure, and these greatly outperformed the prior methods in controlling the false positive rate (FPR); that is, subject-wise bootstrapping (SWB) worked relatively well for both cases with one and two groups, and subject-wise permutation (SWP) testing was virtually ideal for group comparisons. Here we seek to explicate and adopt a parametric approach through linear mixed-effects (LME) modeling for studying the ISC values, building on the previous correlation framework, with the benefit that the LME platform offers wider adaptability, more powerful interpretations, and quality control checking capability than nonparametric methods. We describe both theoretical and practical issues involved in the modeling and the manner in which LME with crossed random effects (CRE) modeling is applied. A data-doubling step further allows us to conveniently track the subject index, and achieve easy implementations. We pit the LME approach against the best nonparametric methods, and find that the LME framework achieves proper control for false positives. The new LME methodologies are shown to be both efficient and robust, and they will be added as an additional option and settings in an existing open source program, 3dLME, in AFNI (http://afni.nimh.nih.gov). PMID:27751943

Water Resources Management In The Eastern Himalayan Urban Ecosystem

NASA Astrophysics Data System (ADS)

Bomjan, S.

The Himalayan ecosystem is one of the most important and threatened ecosystems on the earth. In this region, the scarcity of water in general, and drinking water in par- ticular is affecting common people and drawing the attention of researchers. Given the present situation and governance, in the near future it is most likely to deteriorate further. With expanding population and urbanization, accelerating human activities, and increasing per capita water consumption, problem of water supply in the moun- tain households will be certainly acute in the coming years. This crisis of decreasing availability of water is not only going to hamper the economic development of the region, but is also likely to threaten the very survival of the already marginalised and deprived people who are also on the brink of poverty and are incapable of coping with such crisis. Sustainable water harvesting and management of water resources offers the best hope for meeting the challenges of the growing water crisis. For this appropriate policy intervention, use of latest technology, application of tools like GIS and information from the satellite imageries, community participation and use of tra- ditional knowledge and traditional water management practices will be essential to overcome the challenge of looming water crisis. Darjiling Himalaya, located in the eastern Himalayas has a fragile environment and it is witnessing serious problems both in quality and quantity of water supply. Weak institutional arrangements, lack of awareness among citizens and a gap in the effective arrangements are huge stumbling blocks. This region is endowed with abundance of water resources and rich ecosystem. Therefore, this calls for an effective and participatory water management system with due attention given to the upgradation and expansion of the existing infrastructure. This paper takes a stock of the existing water resources in the Darjiling Himalaya, especially around the town of Darjiling, discusses the problem as perceived by the people and comes out with some viable suggestions.

Teaching Computational Thinking: Deciding to Take Small Steps in a Curriculum

NASA Astrophysics Data System (ADS)

Madoff, R. D.; Putkonen, J.

2016-12-01

While computational thinking and reasoning are not necessarily the same as computer programming, programs such as MATLAB can provide the medium through which the logical and computational thinking at the foundation of science can be taught, learned, and experienced. And while math and computer anxiety are often discussed as critical obstacles to students' progress in their geoscience curriculum, it is here suggested that an unfamiliarity with the computational and logical reasoning is what poses a first stumbling block, in addition to the hurdle of expending the effort to learn how to translate a computational problem into the appropriate computer syntax in order to achieve the intended results. Because computational thinking is so vital for all fields, there is a need to initiate many and to build support in the curriculum for it. This presentation focuses on elements to bring into the teaching of computational thinking that are intended as additions to learning MATLAB programming as a basic tool. Such elements include: highlighting a key concept, discussing a basic geoscience problem where the concept would show up, having the student draw or outline a sketch of what they think an operation needs to do in order to perform a desired result, and then finding the relevant syntax to work with. This iterative pedagogy simulates what someone with more experience in programming does, so it discloses the thinking process in the black box of a result. Intended as only a very early stage introduction, advanced applications would need to be developed as students go through an academic program. The objective would be to expose and introduce computational thinking to majors and non-majors and to alleviate some of the math and computer anxiety so that students would choose to advance on with programming or modeling, whether it is built into a 4-year curriculum or not.

Adolescent Social Isolation as a Model of Heightened Vulnerability to Comorbid Alcoholism and Anxiety Disorders.

PubMed

Butler, Tracy R; Karkhanis, Anushree N; Jones, Sara R; Weiner, Jeffrey L

2016-06-01

Individuals diagnosed with anxiety-related illnesses are at increased risk of developing alcoholism, exhibit a telescoped progression of this disease and fare worse in recovery, relative to alcoholics that do not suffer from a comorbid anxiety disorder. Similarly, preclinical evidence supports the notion that stress and anxiety represent major risk factors for the development of alcohol use disorder (AUD). Despite the importance of understanding the link between anxiety and alcoholism, much remains unknown about the neurobiological substrates underlying this relationship. One stumbling block has been the lack of animal models that reliably reproduce the spectrum of behaviors associated with increased vulnerability to these diseases. Here, we review the literature that has examined the behavioral and neurobiological outcomes of a simple rodent adolescent social isolation procedure and discuss its validity as a model of vulnerability to comorbid anxiety disorders and alcoholism. Recent studies have provided strong evidence that adolescent social isolation of male rats leads to the expression of a variety of behaviors linked with increased vulnerability to anxiety and/or AUD, including deficits in sensory gating and fear extinction, and increases in anxiety measures and ethanol drinking. Neurobiological studies are beginning to identify mesolimbic adaptations that may contribute to the behavioral phenotype engendered by this model. Some of these changes include increased excitability of ventral tegmental area dopamine neurons and pyramidal cells in the basolateral amygdala and significant alterations in baseline and stimulated catecholamine signaling. A growing body of evidence suggests that adolescent social isolation may represent a reliable rodent model of heightened vulnerability to anxiety disorders and alcoholism in male rats. These studies provide initial support for the face, construct, and predictive validity of this model and highlight its utility in identifying neurobiological adaptations associated with increased risk of developing these disorders. Copyright © 2016 by the Research Society on Alcoholism.

A multi-model approach to nucleic acid-based drug development.

PubMed

Gautherot, Isabelle; Sodoyer, Regís

2004-01-01

With the advent of functional genomics and the shift of interest towards sequence-based therapeutics, the past decades have witnessed intense research efforts on nucleic acid-mediated gene regulation technologies. Today, RNA interference is emerging as a groundbreaking discovery, holding promise for development of genetic modulators of unprecedented potency. Twenty-five years after the discovery of antisense RNA and ribozymes, gene control therapeutics are still facing developmental difficulties, with only one US FDA-approved antisense drug currently available in the clinic. Limited predictability of target site selection models is recognized as one major stumbling block that is shared by all of the so-called complementary technologies, slowing the progress towards a commercial product. Currently employed in vitro systems for target site selection include RNAse H-based mapping, antisense oligonucleotide microarrays, and functional screening approaches using libraries of catalysts with randomized target-binding arms to identify optimal ribozyme/DNAzyme cleavage sites. Individually, each strategy has its drawbacks from a drug development perspective. Utilization of message-modulating sequences as therapeutic agents requires that their action on a given target transcript meets criteria of potency and selectivity in the natural physiological environment. In addition to sequence-dependent characteristics, other factors will influence annealing reactions and duplex stability, as well as nucleic acid-mediated catalysis. Parallel consideration of physiological selection systems thus appears essential for screening for nucleic acid compounds proposed for therapeutic applications. Cellular message-targeting studies face issues relating to efficient nucleic acid delivery and appropriate analysis of response. For reliability and simplicity, prokaryotic systems can provide a rapid and cost-effective means of studying message targeting under pseudo-cellular conditions, but such approaches also have limitations. To streamline nucleic acid drug discovery, we propose a multi-model strategy integrating high-throughput-adapted bacterial screening, followed by reporter-based and/or natural cellular models and potentially also in vitro assays for characterization of the most promising candidate sequences, before final in vivo testing.

Space micropropulsion systems for Cubesats and small satellites: From proximate targets to furthermost frontiers

NASA Astrophysics Data System (ADS)

Levchenko, Igor; Bazaka, Kateryna; Ding, Yongjie; Raitses, Yevgeny; Mazouffre, Stéphane; Henning, Torsten; Klar, Peter J.; Shinohara, Shunjiro; Schein, Jochen; Garrigues, Laurent; Kim, Minkwan; Lev, Dan; Taccogna, Francesco; Boswell, Rod W.; Charles, Christine; Koizumi, Hiroyuki; Shen, Yan; Scharlemann, Carsten; Keidar, Michael; Xu, Shuyan

2018-03-01

Rapid evolution of miniaturized, automatic, robotized, function-centered devices has redefined space technology, bringing closer the realization of most ambitious interplanetary missions and intense near-Earth space exploration. Small unmanned satellites and probes are now being launched in hundreds at a time, resurrecting a dream of satellite constellations, i.e., wide, all-covering networks of small satellites capable of forming universal multifunctional, intelligent platforms for global communication, navigation, ubiquitous data mining, Earth observation, and many other functions, which was once doomed by the extraordinary cost of such systems. The ingression of novel nanostructured materials provided a solid base that enabled the advancement of these affordable systems in aspects of power, instrumentation, and communication. However, absence of efficient and reliable thrust systems with the capacity to support precise maneuvering of small satellites and CubeSats over long periods of deployment remains a real stumbling block both for the deployment of large satellite systems and for further exploration of deep space using a new generation of spacecraft. The last few years have seen tremendous global efforts to develop various miniaturized space thrusters, with great success stories. Yet, there are critical challenges that still face the space technology. These have been outlined at an inaugural International Workshop on Micropropulsion and Cubesats, MPCS-2017, a joint effort between Plasma Sources and Application Centre/Space Propulsion Centre (Singapore) and the Micropropulsion and Nanotechnology Lab, the G. Washington University (USA) devoted to miniaturized space propulsion systems, and hosted by CNR-Nanotec—P.Las.M.I. lab in Bari, Italy. This focused review aims to highlight the most promising developments reported at MPCS-2017 by leading world-reputed experts in miniaturized space propulsion systems. Recent advances in several major types of small thrusters including Hall thrusters, ion engines, helicon, and vacuum arc devices are presented, and trends and perspectives are outlined.

47. MAIN WAREHOUSE SECOND LEVEL ADDITION Second level was ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

47. MAIN WAREHOUSE - SECOND LEVEL ADDITION Second level was added in 1941. Note the variety of building materials used in the wall: cement, bricks and finally cement blocks, with wood topping the entire wall. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

Space Shuttle Main Engine: Thirty Years of Innovation

NASA Technical Reports Server (NTRS)

Jue, F. H.; Hopson, George (Technical Monitor)

2002-01-01

The Space Shuttle Main Engine (SSME) is the first reusable, liquid booster engine designed for human space flight. This paper chronicles the 30-year history and achievements of the SSME from authority to proceed up to the latest flight configuration - the Block 2 SSME.

Improving atlas methodology

USGS Publications Warehouse

Robbins, C.S.; Dowell, B.A.; O'Brien, J.

1987-01-01

We are studying a sample of Maryland (2 %) and New Hampshire (4 %) Atlas blocks and a small sample in Maine. These three States used different sampling methods and block sizes. We compare sampling techniques, roadside with off-road coverage, our coverage with that of the volunteers, and different methods of quantifying Atlas results. The 7 1/2' (12-km) blocks used in the Maine Atlas are satisfactory for coarse mapping, but are too large to enable changes to be detected in the future. Most states are subdividing the standard 7 1/2' maps into six 5-km blocks. The random 1/6 sample of 5-km blocks used in New Hampshire, Vermont (published 1985), and many other states has the advantage of permitting detection of some changes in the future, but the disadvantage of leaving important habitats unsampled. The Maryland system of atlasing all 1,200 5-km blocks and covering one out of each six by quarterblocks (2 1/2-km) is far superior if enough observers can be found. A good compromise, not yet attempted, would be to Atlas a 1/6 random sample of 5-km blocks and also one other carefully selected (non-random) block on the same 7 1/2' map--the block that would include the best sample of habitats or elevations not in the random block. In our sample the second block raised the percentage of birds found from 86% of the birds recorded in the 7 1/2' quadrangle to 93%. It was helpful to list the expected species in each block and to revise this list annually. We estimate that 90-100 species could be found with intensive effort in most Maryland blocks; perhaps 95-105 in New Hampshire. It was also helpful to know which species were under-sampled so we could make a special effort to search for these. A total of 75 species per block (or 75% of the expected species in blocks with very restricted habitat diversity) is considered a practical and adequate goal in these States. When fewer than 60 species are found per block, a high proportion of the rarer species are missed, as well as some of the common ones. Similarity indices based on fewer than 60 species per block reflect coverage rather than habitat affinities. Atlas blocks that are ecologically similar should have similarity indices (S) of at least 0.80 to be considered adequately covered. S = 2C/(A + B), where C is the number of species in common and A and B are species totals for each of the two blocks being compared. A series of 15 13-minutes roadside stops yielded more species than 15 off-road stops, but off-road stops always had some species not detected at the roadside stops. A series of timed stops is an excellent way to map relative abundance if the stops are standardized with respect to time of day and weather, and the counts are made by observers of comparable ability. Efforts to estimate Atlas block populations in powers of 10 (as in the French Atlas) have not gained acceptance in U.S.A. Most observers feel unqualified to make estimates. An efficient way to Atlas a block is to make at least 3 early morning visits to 15 or more specific stops. Arrive in the block early enough to check for nocturnal species on at least two days; and after completing the specific stops, search the block for other species and for confirmations.

Capacitor blocks for linear transformer driver stages.

PubMed

Kovalchuk, B M; Kharlov, A V; Kumpyak, E V; Smorudov, G V; Zherlitsyn, A A

2014-01-01

In the Linear Transformer Driver (LTD) technology, the low inductance energy storage components and switches are directly incorporated into the individual cavities (named stages) to generate a fast output voltage pulse, which is added along a vacuum coaxial line like in an inductive voltage adder. LTD stages with air insulation were recently developed, where air is used both as insulation in a primary side of the stages and as working gas in the LTD spark gap switches. A custom designed unit, referred to as a capacitor block, was developed for use as a main structural element of the transformer stages. The capacitor block incorporates two capacitors GA 35426 (40 nF, 100 kV) and multichannel multigap gas switch. Several modifications of the capacitor blocks were developed and tested on the life time and self breakdown probability. Blocks were tested both as separate units and in an assembly of capacitive module, consisting of five capacitor blocks. This paper presents detailed design of capacitor blocks, description of operation regimes, numerical simulation of electric field in the switches, and test results.

Two innovative solutions based on fibre concrete blocks designed for building substructure

NASA Astrophysics Data System (ADS)

Pazderka, J.; Hájek, P.

2017-09-01

Using of fibers in a high-strength concrete allows reduction of the dimensions of small precast concrete elements, which opens up new ways of solution for traditional construction details in buildings. The paper presents two innovative technical solutions for building substructure: The special shaped plinth block from fibre concrete and the fibre concrete elements for new technical solution of ventilated floor. The main advantages of plinth block from fibre concrete blocks (compared with standard plinth solutions) is: easier and faster assembly, higher durability and thanks to the air cavity between the vertical part of the block, the building substructure reduced moisture level of structures under the waterproofing layer and a comprehensive solution to the final surface of building plinth as well as the surface of adjacent terrain. The ventilated floor based on fibre concrete precast blocks is an attractive structural alternative for tackling the problem of increased moisture in masonry in older buildings, lacking a functional waterproof layer in the substructure.

Highly Ordered Block Copolymer Templates for the Generation of Nanostructured Materials

NASA Astrophysics Data System (ADS)

Bhoje Gowd, E.; Nandan, Bhanu; Bigall, Nadja C.; Eychmuller, Alexander; Stamm, Manfred

2009-03-01

Among many different types of self-assembled materials, block copolymers have attracted immense interest for applications in nanotechnology. Block copolymer thin film can be used as a template for patterning of hard inorganic materials such as metal nanoparticles. In the present work, we demonstrate a new approach to fabricate highly ordered arrays of nanoscopic inorganic dots and wires using switchable block copolymer thin films. Various inorganic nanoparticles from a simple aqueous solution were directly deposited on the surface reconstructed block copolymer templates. The preferential interaction of the nanoparticles with one of the blocks is mainly responsible for the lateral distribution of the nanoparticles in addition to the capillary forces. Subsequent stabilization by UV-irradiation followed by pyrolysis in air at 450 ^oC removes the polymer to produce highly ordered metallic nanostructures. This method is highly versatile as the procedure used here is simple, eco-friendly and provides a facile approach to fabricate a broad range of nanoscaled architectures with tunable lateral spacing.

Highly crystalline covalent organic frameworks from flexible building blocks.

PubMed

Xu, Liqian; Ding, San-Yuan; Liu, Junmin; Sun, Junliang; Wang, Wei; Zheng, Qi-Yu

2016-03-28

Two novel 2D covalent organic frameworks (TPT-COF-1 and TPT-COF-2) were synthesized from the flexible 2,4,6-triaryloxy-1,3,5-triazine building blocks on a gram scale, which show high crystallinity and large surface area. The controllable formation of highly ordered frameworks is mainly attributed to the self-assembly Piedfort unit of 2,4,6-triaryloxy-1,3,5-triazine.

Coastal protection using topological interlocking blocks

NASA Astrophysics Data System (ADS)

Pasternak, Elena; Dyskin, Arcady; Pattiaratchi, Charitha; Pelinovsky, Efim

2013-04-01

The coastal protection systems mainly rely on the self-weight of armour blocks to ensure its stability. We propose a system of interlocking armour blocks, which form plate-shape assemblies. The shape and the position of the blocks are chosen in such a way as to impose kinematic constraints that prevent the blocks from being removed from the assembly. The topological interlocking shapes include simple convex blocks such as platonic solids, the most practical being tetrahedra, cubes and octahedra. Another class of topological interlocking blocks is so-called osteomorphic blocks, which form plate-like assemblies tolerant to random block removal (almost 25% of blocks need to be removed for the assembly to loose integrity). Both classes require peripheral constraint, which can be provided either by the weight of the blocks or post-tensioned internal cables. The interlocking assemblies provide increased stability because lifting one block involves lifting (and bending) the whole assembly. We model the effect of interlocking by introducing an equivalent additional self-weight of the armour blocks. This additional self-weight is proportional to the critical pressure needed to cause bending of the interlocking assembly when it loses stability. Using beam approximation we find an equivalent stability coefficient for interlocking. It is found to be greater than the stability coefficient of a structure with similar blocks without interlocking. In the case when the peripheral constraint is provided by the weight of the blocks and for the slope angle of 45o, the effective stability coefficient for a structure of 100 blocks is 33% higher than the one for a similar structure without interlocking. Further increase in the stability coefficient can be reached by a specially constructed peripheral constraint system, for instance by using post-tension cables.

[Application and research progress of subtalar distraction bone block arthrodesis in treatment of calcaneus fracture malunion].

PubMed

Wang, Shanxi; Li, Jun; Huang, Fuguo; Liu, Lei

2017-05-01

To review the application and research progress of subtalar distraction bone block arth-rodesis in the treatment of calcaneus fracture malunion. The recent literature concerning the history, surgical technique, postoperative complication, indications, and curative effect of subtalar distraction arthrodesis with bone graft block interposition in the treatment of calcaneus fracture malunion was summarized and analyzed. Subtalar distraction bone block arthrodesis is one of the main ways to treat calcaneus fracture malunion, including a combined surgery with subtalar arthrodesis and realignment surgery for hindfoot deformity using bone block graft. The advantage is on the base of subtalar joint fusion, through one-time retracting subtalar joint, the posterior articular surface of subtalar joint implants bone block can partially restore calcaneal height, thus improving the function of the foot. Compared with other calcaneal malunion treatments, subtalar distraction arthrodesis is effective to correct complications caused by calcaneus fracture malunion, and it can restore the height of talus and calcaneus, correct loss of talocalcaneal angle, and ease pain. Subtalar distraction bone block arthrodesis has made remarkable progress in the treatment of calcaneus fracture malunion, but it has the disadvantages of postoperative nonunion and absorption of bone block, so further study is needed.

Synthesis of regional crust and upper-mantle structure from seismic and gravity data

NASA Technical Reports Server (NTRS)

Alexander, S. S.; Lavin, P. M. (Principal Investigator)

1982-01-01

Analyses of regional gravity and magnetic patterns, LANDSAT images and geological information revealed two major lineaments crossing western Pennsylvania and parts of surrounding states. These lineaments are inferred to be expressions of fracture zones which penetrare deeply into the crust and possibly the upper mantle. The extensions of the Tyron-Mt. Union and the Pittsburgh-Washington lineaments bound a distinct crustal block (Lake Erie-Maryland block) over 100 km wide and probably more than 600 km in length. Evidence exists for the lateral displacement of this block at least 60 km northwestward during late Precambrian to Lower Ordovician time. Subsequent movements have been mainly vertical with respect to neighboring blocks. A possible crustal block that passes through eastern Kentucky, proposed by a TVA study on tectonics in the southern Appalachians, was also investigated. Finally, the use of regional gravity and magnetic data in identifying major crustal structures beneath western Pennsylvania is discussed.

Resolving writer's block.

PubMed Central

Huston, P.

1998-01-01

PROBLEM BEING ADDRESSED: Writer's block, or a distinctly uncomfortable inability to write, can interfere with professional productivity. OBJECTIVE OF PROGRAM: To identify writer's block and to outline suggestions for its early diagnosis, treatment, and prevention. MAIN COMPONENTS OF PROGRAM: Once the diagnosis has been established, a stepwise approach to care is recommended. Mild blockage can be resolved by evaluating and revising expectations, conducting a task analysis, and giving oneself positive feedback. Moderate blockage can be addressed by creative exercises, such as brainstorming and role-playing. Recalcitrant blockage can be resolved with therapy. Writer's block can be prevented by taking opportunities to write at the beginning of projects, working with a supportive group of people, and cultivating an ongoing interest in writing. CONCLUSIONS: Writer's block is a highly treatable condition. A systematic approach can help to alleviate anxiety, build confidence, and give people the information they need to work productively. PMID:9481467

Combining techniques for screening and evaluating interaction terms on high-dimensional time-to-event data.

PubMed

Sariyar, Murat; Hoffmann, Isabell; Binder, Harald

2014-02-26

Molecular data, e.g. arising from microarray technology, is often used for predicting survival probabilities of patients. For multivariate risk prediction models on such high-dimensional data, there are established techniques that combine parameter estimation and variable selection. One big challenge is to incorporate interactions into such prediction models. In this feasibility study, we present building blocks for evaluating and incorporating interactions terms in high-dimensional time-to-event settings, especially for settings in which it is computationally too expensive to check all possible interactions. We use a boosting technique for estimation of effects and the following building blocks for pre-selecting interactions: (1) resampling, (2) random forests and (3) orthogonalization as a data pre-processing step. In a simulation study, the strategy that uses all building blocks is able to detect true main effects and interactions with high sensitivity in different kinds of scenarios. The main challenge are interactions composed of variables that do not represent main effects, but our findings are also promising in this regard. Results on real world data illustrate that effect sizes of interactions frequently may not be large enough to improve prediction performance, even though the interactions are potentially of biological relevance. Screening interactions through random forests is feasible and useful, when one is interested in finding relevant two-way interactions. The other building blocks also contribute considerably to an enhanced pre-selection of interactions. We determined the limits of interaction detection in terms of necessary effect sizes. Our study emphasizes the importance of making full use of existing methods in addition to establishing new ones.

Phase-space dissimilarity measures for industrial and biomedical applications

NASA Astrophysics Data System (ADS)

Protopopescu, V. A.; Hively, L. M.

2005-12-01

One of the most important problems in time-series analysis is the suitable characterization of the dynamics for timely, accurate, and robust condition assessment of the underlying system. Machine and physiological processes display complex, non-stationary behaviors that are affected by noise and may range from (quasi-)periodic to completely irregular (chaotic) regimes. Nevertheless, extensive experimental evidence indicates that even when the systems behave very irregularly (e.g., severe tool chatter or cardiac fibrillation), one may assume that - for all practical purposes - the dynamics are confined to low dimensional manifolds. As a result, the behavior of these systems can be described via traditional nonlinear measures (TNM), such as Lyapunov exponents, Kolmogorov entropy, and correlation dimension. While these measures are adequate for discriminating between clear-cut regular and chaotic dynamics, they are not sufficiently sensitive to distinguish between slightly different irregular (chaotic) regimes, especially when data are noisy and/or limited. Both machine and physiological dynamics usually fall into this latter category, creating a massive stumbling block to prognostication of abnormal regimes. We present here a recently developed approach that captures more efficiently changes in the underlying dynamics. We start with process-indicative, time-serial data that are checked for quality and discarded if inadequate. Acceptable data are filtered to remove confounding artifacts (e.g., sinusoidal variation in three-phase electrical signals or eye-blinks and muscular activity in EEG). The artifact-filtered data are then used to recover the essential features of the underlying dynamics via standard time-delay, phase-space reconstruction. One of the main results of this reconstruction is a discrete approximation of the distribution function (DF) on the attractor. Unaltered dynamics yield an unchanging geometry of the attractor and the visitation frequencies of its various points, corresponding to the baseline DF. Condition change is established by comparing the base line DFs to subsequent test case DFs via new, phase space dissimilarity measures (PSDM), namely the distance and - square statistics between two DFs. A clear trend in the dissimilarity measures over time indicates substantial departure from the baseline dynamics, thus signaling condition change. The severity of this departure can be interpreted as a "normal" fluctuation, abnormal behavior, impending failure, or complete breakdown. We illustrate the new approach on an assortment of machinery and biomedical examples. The machine data were collected during laboratory tests on industrial equipment, for diverse failure modes, via seeded faults and accelerated failures. The biomedical applications involve detection of physiological changes, such as epileptic seizures from EEG; ventricular fibrillation, fainting, and sepsis onset from ECG; and breathing difficulty from chest sounds. The PSDM show a consistent discrimination of normal-to-abnormal transitions, allowing earlier, more accurate, and more robust detection of the dynamical change for all of these applications in comparison to TNM.

[Pharmacotherapy of panic disorder].

PubMed

Bougerol, T; Farisse, J

1996-12-01

The concept of Panic Disorders has itself been developed on the strength of therapeutic effects of drug treatments and it is therefore not surprising that psychotropic medications are currently the main therapeutic tool for this condition. Their use may be indicated in two differing circumstances, as treatment for Panic Attack itself or as a long-term treatment for what is properly called Panic Disorder. The latter scenario is that which has been most actively studied and represents the more original side of the question. Treatment of acute Panic Attack involves administration of sedative anxiolytics, principally benzodiazepines (BZD). Long-term treatment aiming to prevent repeated attacks is the core strategy for treatment for Panic Disorder. For the past fifteen years, a large number of research projects have shown the elective anti-panic efficacy of a number of drugs, principally antidepressants and anxiolytics. The response profile to anti-depressant treatment is characterized by a lag time which is sometimes longer than that observed when they are used solely as antidepressants; frequently they are also less well tolerated which necessitates a very gradual step-up in dosage. The "classic" MAOI (non-selective and irreversible) have a proven anti-panic effect. Selective serotonin reuptake inhibitor (SSRI) anti-depressants are currently drugs of choice in the treatment of Panic Disorder. Although the anti-panic effect appears to be common to all the various SSRI drugs available, and directly attributable to their mechanism of action, not all of them however have undergone controlled studies. In France, paroxetine is the first anti-depressant in this group to obtain a marketing authorization for this particular indication. The advantages of the SSRI drugs are principally related to their limited adverse effects and lack of toxicity, thereby making them particularly straightforward to use. Benzodiazepines (BZD) are the second group of psychotropic medications which have been shown to be effective in the treatment of Panic Disorder. The major disadvantage of the BZD for this indication is chiefly related to the major risk of promoting a dependency state with the corresponding appearance of a withdrawal syndrome when treatment is stopped. This risk constitutes a major stumbling block to the use of BZD as a first-line treatment for Panic Disorder. Various other drugs have been evaluated in the treatment of Panic Disorder with varying success. The current anti-panic pharmacopoeia therefore appears to be relatively well stocked. In this context, antidepressants-especially the SSRI drugs-are the first-line treatment of choice for Panic Disorders. In all cases, it appears useful to integrate pharmacological treatment within an overall management plan for the patient with Panic Disorder, especially if it is hoped to maintain therapeutic benefit long-term.

Permutation testing of orthogonal factorial effects in a language-processing experiment using fMRI.

PubMed

Suckling, John; Davis, Matthew H; Ooi, Cinly; Wink, Alle Meije; Fadili, Jalal; Salvador, Raymond; Welchew, David; Sendur, Levent; Maxim, Vochita; Bullmore, Edward T

2006-05-01

The block-paradigm of the Functional Image Analysis Contest (FIAC) dataset was analysed with the Brain Activation and Morphological Mapping software. Permutation methods in the wavelet domain were used for inference on cluster-based test statistics of orthogonal contrasts relevant to the factorial design of the study, namely: the average response across all active blocks, the main effect of speaker, the main effect of sentence, and the interaction between sentence and speaker. Extensive activation was seen with all these contrasts. In particular, different vs. same-speaker blocks produced elevated activation in bilateral regions of the superior temporal lobe and repetition suppression for linguistic materials (same vs. different-sentence blocks) in left inferior frontal regions. These are regions previously reported in the literature. Additional regions were detected in this study, perhaps due to the enhanced sensitivity of the methodology. Within-block sentence suppression was tested post-hoc by regression of an exponential decay model onto the extracted time series from the left inferior frontal gyrus, but no strong evidence of such an effect was found. The significance levels set for the activation maps are P-values at which we expect <1 false-positive cluster per image. Nominal type I error control was verified by empirical testing of a test statistic corresponding to a randomly ordered design matrix. The small size of the BOLD effect necessitates sensitive methods of detection of brain activation. Permutation methods permit the necessary flexibility to develop novel test statistics to meet this challenge.

Bootstrap study of genome-enabled prediction reliabilities using haplotype blocks across Nordic Red cattle breeds.

PubMed

Cuyabano, B C D; Su, G; Rosa, G J M; Lund, M S; Gianola, D

2015-10-01

This study compared the accuracy of genome-enabled prediction models using individual single nucleotide polymorphisms (SNP) or haplotype blocks as covariates when using either a single breed or a combined population of Nordic Red cattle. The main objective was to compare predictions of breeding values of complex traits using a combined training population with haplotype blocks, with predictions using a single breed as training population and individual SNP as predictors. To compare the prediction reliabilities, bootstrap samples were taken from the test data set. With the bootstrapped samples of prediction reliabilities, we built and graphed confidence ellipses to allow comparisons. Finally, measures of statistical distances were used to calculate the gain in predictive ability. Our analyses are innovative in the context of assessment of predictive models, allowing a better understanding of prediction reliabilities and providing a statistical basis to effectively calibrate whether one prediction scenario is indeed more accurate than another. An ANOVA indicated that use of haplotype blocks produced significant gains mainly when Bayesian mixture models were used but not when Bayesian BLUP was fitted to the data. Furthermore, when haplotype blocks were used to train prediction models in a combined Nordic Red cattle population, we obtained up to a statistically significant 5.5% average gain in prediction accuracy, over predictions using individual SNP and training the model with a single breed. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Meta-Analytic Evidence for a Reversal Learning Effect on the Iowa Gambling Task in Older Adults.

PubMed

Pasion, Rita; Gonçalves, Ana R; Fernandes, Carina; Ferreira-Santos, Fernando; Barbosa, Fernando; Marques-Teixeira, João

2017-01-01

Iowa Gambling Task (IGT) is one of the most widely used tools to assess economic decision-making. However, the research tradition on aging and the Iowa Gambling Task (IGT) has been mainly focused on the overall performance of older adults in relation to younger or clinical groups, remaining unclear whether older adults are capable of learning along the task. We conducted a meta-analysis to examine older adults' decision-making on the IGT, to test the effects of aging on reversal learning (45 studies) and to provide normative data on total and block net scores (55 studies). From the accumulated empirical evidence, we found an average total net score of 7.55 (±25.9). We also observed a significant reversal learning effect along the blocks of the IGT, indicating that older adults inhibit the prepotent response toward immediately attractive options associated with high losses, in favor of initially less attractive options associated with long-run profit. During block 1, decisions of older adults led to a negative gambling net score, reflecting the expected initial pattern of risk-taking. However, the shift toward more safe options occurred between block 2 (small-to-medium effect size) and blocks 3, 4, 5 (medium-to-large effect size). These main findings highlight that older adults are able to move from the initial uncertainty, when the possible outcomes are unknown, to decisions based on risk, when the outcomes are learned and may be used to guide future adaptive decision-making.

DSN system performance test software

NASA Technical Reports Server (NTRS)

Martin, M.

1978-01-01

The system performance test software is currently being modified to include additional capabilities and enhancements. Additional software programs are currently being developed for the Command Store and Forward System and the Automatic Total Recall System. The test executive is the main program. It controls the input and output of the individual test programs by routing data blocks and operator directives to those programs. It also processes data block dump requests from the operator.

Newer regional analgesia interventions (fascial plane blocks) for breast surgeries: Review of literature.

PubMed

Garg, Rakesh; Bhan, Swati; Vig, Saurabh

2018-04-01

Surgical resection of the primary tumour with axillary dissection is one of the main modalities of breast cancer treatment. Regional blocks have been considered as one of the modalities for effective perioperative pain control. With the advent of ultrasound, newer interventions such as fascial plane blocks have been reported for perioperative analgesia in breast surgeries. Our aim is to review the literature for fascial plane blocks for analgesia in breast surgeries. The research question for initiating the review was 'What are the reported newer regional anaesthesia techniques (fascial plane blocks) for female patients undergoing breast surgery and their analgesic efficacy?.' The participants, intervention, comparisons, outcomes and study design were followed. Due to the paucity of similar studies and heterogeneity, the assessment of bias, systematic review or pooled analysis/meta-analysis was not feasible. Of the 989 manuscripts, the present review included 28 manuscripts inclusive of all types of published manuscripts. 15 manuscripts directly related to the administration of fascial plane blocks for breast surgery across all type of study designs and cases were reviewed for the utility of fascial plane blocks in breast surgeries. Interfascial blocks score over regional anaesthetic techniques such as paravertebral block as they have no risk of sympathetic blockade, intrathecal or epidural spread which may lead to haemodynamic instability and prolonged hospital stay. This review observed that no block effectively covers the whole of breast and axilla, thus a combination of blocks should be used depending on the site of incision and extent of surgical resection.

Strong effects of predation by fishes on an invasive macroinvertebrate in a large floodplain river

USGS Publications Warehouse

Bartsch, M.R.; Bartsch, L.A.; Gutreuter, S.

2005-01-01

We assessed the effects of fish predation on zebra mussels (Dreissena polymorpha) in Navigation Pool 8 of the Upper Mississippi River from 13 May to 5 October, 1998. Concrete-block samplers were deployed at 18 randomly chosen sites in the main-channel border, with 6 sites in the upper, middle, and lower segments of the pool. Two blocks, 1 of which was enclosed in a cage to exclude large predatory fishes, were deployed at each site. After 145 d, blocks were retrieved from 12 of the 18 sites, and zebra mussels were found on all blocks. Densities of zebra mussels were higher on caged blocks than uncaged blocks, and the magnitudes of the differences varied spatially. Mean mussel densities on uncaged blocks were reduced by 66%, 86%, and 20% compared to caged blocks in the upper, middle, and lower pool segments, respectively, over the 145-d interval. Mean daily instantaneous zebra mussel mortality rates from large predators ranged from 0.0016 to 0.0138. Similarly, biomass of zebra mussels was higher on caged than uncaged blocks. Mean mussel biomass on uncaged blocks was reduced by 64% pool-wide, relative to biomass on caged blocks. Zebra mussels were consumed by at least 6 fish taxa including redhorse stickers (Moxostoma spp.), common carp (Cyprinus carpio), bluegill (Lepomis macrochirus), quillback carpsucker (Carpiodes cyprinus), flathead catfish (Pylodictis olivaris), and freshwater drum (Aplodinotus grunniens). Fish predation had an important moderating effect on zebra mussel demography in Pool 8.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Girelli, Florian; Livine, Etera R.; Laboratoire de Physique, ENS Lyon, CNRS UMR 5672, 46 Allee d'Italie, 69007 Lyon

Deformed special relativity (DSR) is obtained by imposing a maximal energy to special relativity and deforming the Lorentz symmetry (more exactly, the Poincare symmetry) to accommodate this requirement. One can apply the same procedure in the context of Galilean relativity by imposing a maximal speed (the speed of light). Effectively, one deforms the Galilean group and this leads to a noncommutative space structure, together with the deformations of composition of speed and conservation of energy momentum. In doing so, one runs into most of the ambiguities that one stumbles onto in the DSR context. However, this time, special relativity ismore » there to tell us what is the underlying physics, in such a way we can understand and interpret these ambiguities. We use these insights to comment on the physics of DSR.« less

Human induced pluripotent stem cell‐derived versus adult cardiomyocytes: an in silico electrophysiological study on effects of ionic current block

PubMed Central

Paci, M; Hyttinen, J; Rodriguez, B

2015-01-01

Background and Purpose Two new technologies are likely to revolutionize cardiac safety and drug development: in vitro experiments on human‐induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) and in silico human adult ventricular cardiomyocyte (hAdultV‐CM) models. Their combination was recently proposed as a potential replacement for the present hERG‐based QT study for pharmacological safety assessments. Here, we systematically compared in silico the effects of selective ionic current block on hiPSC‐CM and hAdultV‐CM action potentials (APs), to identify similarities/differences and to illustrate the potential of computational models as supportive tools for evaluating new in vitro technologies. Experimental Approach In silico AP models of ventricular‐like and atrial‐like hiPSC‐CMs and hAdultV‐CM were used to simulate the main effects of four degrees of block of the main cardiac transmembrane currents. Key Results Qualitatively, hiPSC‐CM and hAdultV‐CM APs showed similar responses to current block, consistent with results from experiments. However, quantitatively, hiPSC‐CMs were more sensitive to block of (i) L‐type Ca2+ currents due to the overexpression of the Na+/Ca2+ exchanger (leading to shorter APs) and (ii) the inward rectifier K+ current due to reduced repolarization reserve (inducing diastolic potential depolarization and repolarization failure). Conclusions and Implications In silico hiPSC‐CMs and hAdultV‐CMs exhibit a similar response to selective current blocks. However, overall hiPSC‐CMs show greater sensitivity to block, which may facilitate in vitro identification of drug‐induced effects. Extrapolation of drug effects from hiPSC‐CM to hAdultV‐CM and pro‐arrhythmic risk assessment can be facilitated by in silico predictions using biophysically‐based computational models. PMID:26276951

A Randomized Controlled Trial Examining the Effect of the Addition of the Mandibular Block to Cervical Plexus Block for Carotid Endarterectomy.

PubMed

Kavrut Ozturk, Nilgun; Kavakli, Ali Sait; Sagdic, Kadir; Inanoglu, Kerem; Umot Ayoglu, Raif

2018-04-01

Although the cervical plexus block generally provides adequate analgesia for carotid endarterectomy, pain caused by metal retractors on the inferior surface of the mandible is not prevented by the cervical block. Different pain relief methods can be performed for patients who experience discomfort in these areas. In this study, the authors evaluated the effect of mandibular block in addition to cervical plexus block on pain scores in carotid endarterectomy. A prospective, randomized, controlled trial. Training and research hospital. Patients who underwent a carotid endarterectomy. Patients scheduled for carotid endarterectomy under cervical plexus block were randomized into 2 groups: group 1 (those who did not receive a mandibular block) and group 2 (those who received a mandibular block). The main purpose of the study was to evaluate the mandibular block in addition to cervical plexus block in terms of intraoperative pain scores. Intraoperative visual analog scale scores were significantly higher in group 1 (p = 0.001). The amounts of supplemental 1% lidocaine and intraoperative intravenous analgesic used were significantly higher in group 1 (p = 0.001 and p = 0.035, respectively). Patient satisfaction scores were significantly lower in group 1 (p = 0.044). The amount of postoperative analgesic used, time to first analgesic requirement, postoperative visual analog scale scores, and surgeon satisfaction scores were similar in both groups. There was no significant difference between the groups with respect to complications. No major neurologic deficits or perioperative mortality were observed. Mandibular block in addition to cervical plexus block provides better intraoperative pain control and greater patient satisfaction than cervical plexus block alone. Copyright © 2017 Elsevier Inc. All rights reserved.

Nonalcoholic fatty liver disease is associated with an increased risk of heart block in hospitalized patients with type 2 diabetes mellitus.

PubMed

Mantovani, Alessandro; Rigolon, Riccardo; Pichiri, Isabella; Bonapace, Stefano; Morani, Giovanni; Zoppini, Giacomo; Bonora, Enzo; Targher, Giovanni

2017-01-01

Recent studies suggested that nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of cardiac tachyarrhythmias (mainly atrial fibrillation) in patients with and without type 2 diabetes mellitus. The aim of this study was to examine whether an association also exists between NAFLD and heart block. We have retrospectively evaluated a hospital-based cohort of 751 patients with type 2 diabetes discharged from our Division of Diabetes and Endocrinology during years 2007-2014. Standard electrocardiograms were performed on all patients. Diagnosis of NAFLD was based on ultrasonography, whereas the severity of advanced hepatic fibrosis was based on the fibrosis (FIB)-4 score and other non-invasive fibrosis markers. Overall, 524 (69.8%) patients had NAFLD and 202 (26.9%) had heart block (defined as at least one block among first-degree atrio-ventricular block, second-degree block, third-degree block, left bundle branch block, right bundle branch block, left anterior hemi-block or left posterior hemi-block) on electrocardiograms. Patients with NAFLD had a remarkably higher prevalence of any persistent heart block than those without NAFLD (31.3% vs. 16.7%, p<0.001); this prevalence was particularly increased among those with higher FIB-4 score. NAFLD was associated with a threefold increased risk of prevalent heart block (adjusted-odds ratio 3.04, 95% CI 1.81-5.10), independently of age, sex, hypertension, prior ischemic heart disease, hemoglobin A1c, microvascular complication status, use of medications and other potentially confounding factors. In conclusion, this is the largest cross-sectional study to show that NAFLD and its severity are independently associated with an increased risk of prevalent heart block in hospitalized patients with type 2 diabetes.

Detrital zircons from phanerozoic rocks of the Songliao Block, NE China: Evidence and tectonic implications

NASA Astrophysics Data System (ADS)

Zhou, Jian-Bo; Wilde, Simon A.; Zhang, Xing-Zhou; Liu, Fu-Lai; Liu, Jian-Hui

2012-03-01

Rocks that crop out in the northern part of the Songliao Block are mainly consist of high-grade metamorphic gneiss, Paleozoic strata and Mesozoic granites. They are essentially similar to rocks reported from beneath the Songliao Basin that occupies the majority of the Songliao Block. Four samples of Paleozoic metasedimentary rocks from Tieli in the north-eastern part of the Songliao Block yield detrital zircon U-Pb ages ranging from 2690 to 501 Ma, with four age populations at: 2071-2690 Ma, with a peak at 2585 Ma; 1776-1997 Ma, with a peak at 1890 Ma; 719-991 Ma, with a peak at 800 Ma; and 501-592 Ma, with a peak at 518 Ma. These are similar to age populations in other parts of the Central Asian Orogenic Belt (CAOB), although sediments from the Songliao Block contain more abundant Archean and Proterozoic detrital zircons than the neighboring Jiamusi-Khanka Block to the east and Xing'an Block to the west. This may indicate that rocks of this age comprise a minor component of the Songliao Block. The Pan-African zircon ages from the Songliao Block, taken together with ˜500 Ma magmatic and high-grade metamorphic zircons obtained from the nearby Erguna, Xing'an and Jiamusi-Khanka blocks, indicate that Pan-African events affected all blocks of the CAOB in NE China. This suggests that these blocks not only share a common basement, but that they had a common history. An extensive Late Pan-African (˜500 Ma) orogenic terrane thus occupies much of the CAOB in NE China.

Plasma block acceleration based upon the interaction between double targets and an ultra-intense linearly polarized laser pulse

NASA Astrophysics Data System (ADS)

Xu, Yanxia; Wang, Jiaxiang; Hora, Heinrich; Qi, Xin; Xing, Yifan; Yang, Lei; Zhu, Wenjun

2018-04-01

A new scheme of plasma block acceleration based upon the interaction between double targets and an ultra-intense linearly polarized laser pulse with intensity I ˜ 1022 W/cm2 is investigated via two-dimensional particle-in-cell simulations. The targets are composed of a pre-target of low-density aluminium plasma and an overdense main-target of hydrogen plasma. Through intensive parameter optimization, we have observed highly efficient plasma block accelerations with a monochromatic proton beam peaked at GeVs. The underlying mechanism is attributed to the enhancement of the charge separation field due to the properly selected pre-target.

Microfluidic assembly blocks.

PubMed

Rhee, Minsoung; Burns, Mark A

2008-08-01

An assembly approach for microdevice construction using prefabricated microfluidic components is presented. Although microfluidic systems are convenient platforms for biological assays, their use in the life sciences is still limited mainly due to the high-level fabrication expertise required for construction. This approach involves prefabrication of individual microfluidic assembly blocks (MABs) in PDMS that can be readily assembled to form microfluidic systems. Non-expert users can assemble the blocks on glass slides to build their devices in minutes without any fabrication steps. In this paper, we describe the construction and assembly of the devices using the MAB methodology, and demonstrate common microfluidic applications including laminar flow development, valve control, and cell culture.

Maximum volume cuboids for arbitrarily shaped in-situ rock blocks as determined by discontinuity analysis—A genetic algorithm approach

NASA Astrophysics Data System (ADS)

Ülker, Erkan; Turanboy, Alparslan

2009-07-01

The block stone industry is one of the main commercial use of rock. The economic potential of any block quarry depends on the recovery rate, which is defined as the total volume of useful rough blocks extractable from a fixed rock volume in relation to the total volume of moved material. The natural fracture system, the rock type(s) and the extraction method used directly influence the recovery rate. The major aims of this study are to establish a theoretical framework for optimising the extraction process in marble quarries for a given fracture system, and for predicting the recovery rate of the excavated blocks. We have developed a new approach by taking into consideration only the fracture structure for maximum block recovery in block quarries. The complete model uses a linear approach based on basic geometric features of discontinuities for 3D models, a tree structure (TS) for individual investigation and finally a genetic algorithm (GA) for the obtained cuboid volume(s). We tested our new model in a selected marble quarry in the town of İscehisar (AFYONKARAHİSAR—TURKEY).

Impact of atmospheric blocking events on the decrease of precipitation in the Selenga River basin

NASA Astrophysics Data System (ADS)

Antokhina, O.; Antokhin, P.; Devyatova, E.; Vladimir, M.

2017-12-01

The periods of prolonged deficiency of hydropower potential (HP) of Angara cascade hydroelectric plant related to low-inflow in Baikal and Angara basins threaten to energy sector of Siberia. Since 1901 was recorded five such periods. Last period began in 1996 and continues today. This period attracts the special attention, because it is the longest and coincided with the observed climate change. In our previous works we found that the reason of observed decrease of HP is low water content of Selenga River (main river in Baikal Basin). We also found that the variations of Selenga water-content almost totally depend of summer atmospheric precipitation. Most dramatic decrease of summer precipitation observed in July. In turn, precipitation in July depends on location and intensity of atmospheric frontal zone which separates mid-latitude circulation and East Asia monsoon system. Recently occur reduction this frontal zone and decrease of East Asia summer monsoon intensity. We need in the understanding of the reasons leading to these changes. In the presented work we investigate the influence of atmospheric blocking over Asia on the East Asian summer monsoon circulation in the period its maximum (July). Based on the analysis of large number of blocking events we identified the main mechanisms of blocking influence on the monsoon and studied the properties of cyclones formed by the interaction of air masses from mid latitude and tropics. It turned out that the atmospheric blockings play a fundamental role in the formation of the East Asia monsoon moisture transport and in the precipitation anomalies redistribution. In the absence of blockings over Asia East Asian monsoon moisture does not extend to the north, and in the presence of blockings their spatial configuration and localization completely determines the precipitation anomalies configuration in the northern part of East Asia. We also found that the weakening monsoon circulation in East Asia is associated with decrease in the frequency of atmospheric blocking events in the longitudinal sector width of about 30° with the center of the lake Baikal. The study was supported by the Russian Scientific Foundation Project No. 17-77-10035.

Influence of blocking on Northern European and Western Russian heatwaves in large climate model ensembles

NASA Astrophysics Data System (ADS)

Schaller, N.; Sillmann, J.; Anstey, J.; Fischer, E. M.; Grams, C. M.; Russo, S.

2018-05-01

Better preparedness for summer heatwaves could mitigate their adverse effects on society. This can potentially be attained through an increased understanding of the relationship between heatwaves and one of their main dynamical drivers, atmospheric blocking. In the 1979–2015 period, we find that there is a significant correlation between summer heatwave magnitudes and the number of days influenced by atmospheric blocking in Northern Europe and Western Russia. Using three large global climate model ensembles, we find similar correlations, indicating that these three models are able to represent the relationship between extreme temperature and atmospheric blocking, despite having biases in their simulation of individual climate variables such as temperature or geopotential height. Our results emphasize the need to use large ensembles of different global climate models as single realizations do not always capture this relationship. The three large ensembles further suggest that the relationship between summer heatwaves and atmospheric blocking will not change in the future. This could be used to statistically model heatwaves with atmospheric blocking as a covariate and aid decision-makers in planning disaster risk reduction and adaptation to climate change.

Identification and Reconfigurable Control of Impaired Multi-Rotor Drones

NASA Technical Reports Server (NTRS)

Stepanyan, Vahram; Krishnakumar, Kalmanje; Bencomo, Alfredo

2016-01-01

The paper presents an algorithm for control and safe landing of impaired multi-rotor drones when one or more motors fail simultaneously or in any sequence. It includes three main components: an identification block, a reconfigurable control block, and a decisions making block. The identification block monitors each motor load characteristics and the current drawn, based on which the failures are detected. The control block generates the required total thrust and three axis torques for the altitude, horizontal position and/or orientation control of the drone based on the time scale separation and nonlinear dynamic inversion. The horizontal displacement is controlled by modulating the roll and pitch angles. The decision making algorithm maps the total thrust and three torques into the individual motor thrusts based on the information provided by the identification block. The drone continues the mission execution as long as the number of functioning motors provide controllability of it. Otherwise, the controller is switched to the safe mode, which gives up the yaw control, commands a safe landing spot and descent rate while maintaining the horizontal attitude.

Feasibility of blocking detection in observations from radio occultation

NASA Astrophysics Data System (ADS)

Brunner, Lukas; Steiner, Andrea Karin; Scherllin-Pirscher, Barbara; Jury, Martin

2015-04-01

Blocking describes an atmospheric situation in which the climatological westerly flow at mid latitudes is weakened or reversed. This is caused by a persistent high pressure system which can be stationary for several days to weeks. In the Northern Hemisphere blocking preferably occurs over the Atlantic/European and the Pacific regions. In recent years blocking has been under close scientific investigation due to its effect on weather extremes, triggering heat waves in summer and cold spells in winter. So far, scientific literature mainly focused on the investigation of blocking in reanalysis and global climate model data sets. However, blocking is underestimated in most climate models due to small-scale processes involved in its evolution. For a detection of blocking, most commonly applied methods are based on the computation of meridional geopotential height gradients at the 500 hPa level. Therefore measurements with adequate vertical, horizontal, and temporal resolution and coverage are required. We use an observational data set based on Global Positioning System (GPS) Radio Occultation (RO) measurements fulfilling these requirements. RO is a relatively new, satellite based remote sensing technique, delivering profiles of atmospheric parameters such as geopotential height, pressure, and temperature. It is characterized by favorable properties like long-term stability, global coverage, and high vertical resolution. Our data set is based on the most recent WEGC RO retrieval. Here we report on a feasibility study for blocking detection and analysis in RO data for two exemplary blocking events: the blocking over Russia in summer 2010 and the blocking over Greenland in late winter 2013. For these two events about 700 RO measurements per day are available in the Northern Hemisphere. We will show that the measurement density and quality of RO observations are favorable for blocking analysis and can therefore contribute to blocking research.

A Simple Constant-Current Neural Stimulator With Accurate Pulse-Amplitude Control

DTIC Science & Technology

2001-10-25

STIMULATOR The block diagram of the proposed neurostimulator is displayed in Figure 1. It consists of a pair of transformers followed by full-bridge...to 6%. Pulse-repetition ranges from 1Hz to 10Hz. Figure 1. Block diagram of the neurostimulator Voltage Regulator T 1 Astable T 2 V/I...discrete transistors. For explanatory reasons, the neurostimulator schematic is split into three main elements: the oscillator, the output V/I converter

Understanding and Resolution of the Block 2 SSME, STS-104 Engine Shutdown Pressure Surge In-flight Anomaly

NASA Technical Reports Server (NTRS)

Greene, William D.; Kynard, Michael H.; Tiller, Bruce K. (Technical Monitor)

2002-01-01

STS-104, launched July 2001, marked the first flight of a single Block 2 Space Shuttle Main Engine (SSME). This new configuration of the SSME is the culmination of well over a decade of gradual engine system upgrades. The launch and mission were a success. However, in the process of post-launch data analysis a Main Propulsion System (MPS) anomaly was noted and tied directly to the shutdown of the Block 2 SSME. An investigation into this anomaly was organized across NASA facilities and across the various hardware component contractors. This paper is a very brief summary of the eventual understanding of the root causes of the anomaly and the process whereby an appropriate mitigation action was proposed. An analytical model of the High Pressure Fuel Pump (HPFP) and the low pressure fuel system of the SSME is presented to facilitate the presentation of this summary. The proposed mitigation action is discussed and, with the launch of STS-108 in November 2001, successfully demonstrated under flight conditions.

Meta-Analytic Evidence for a Reversal Learning Effect on the Iowa Gambling Task in Older Adults

PubMed Central

Pasion, Rita; Gonçalves, Ana R.; Fernandes, Carina; Ferreira-Santos, Fernando; Barbosa, Fernando; Marques-Teixeira, João

2017-01-01

Iowa Gambling Task (IGT) is one of the most widely used tools to assess economic decision-making. However, the research tradition on aging and the Iowa Gambling Task (IGT) has been mainly focused on the overall performance of older adults in relation to younger or clinical groups, remaining unclear whether older adults are capable of learning along the task. We conducted a meta-analysis to examine older adults' decision-making on the IGT, to test the effects of aging on reversal learning (45 studies) and to provide normative data on total and block net scores (55 studies). From the accumulated empirical evidence, we found an average total net score of 7.55 (±25.9). We also observed a significant reversal learning effect along the blocks of the IGT, indicating that older adults inhibit the prepotent response toward immediately attractive options associated with high losses, in favor of initially less attractive options associated with long-run profit. During block 1, decisions of older adults led to a negative gambling net score, reflecting the expected initial pattern of risk-taking. However, the shift toward more safe options occurred between block 2 (small-to-medium effect size) and blocks 3, 4, 5 (medium-to-large effect size). These main findings highlight that older adults are able to move from the initial uncertainty, when the possible outcomes are unknown, to decisions based on risk, when the outcomes are learned and may be used to guide future adaptive decision-making. PMID:29075222

Using the internet for suicide-related purposes: Contrasting findings from young people in the community and self-harm patients admitted to hospital.

PubMed

Biddle, Lucy; Derges, Jane; Goldsmith, Carlie; Donovan, Jenny L; Gunnell, David

2018-01-01

Despite accelerating interest in the impact of the internet on suicidal behaviour, empirical work has not captured detailed narratives from those who engaged in suicide-related internet use. This study explored the suicide-related online behaviour of two contrasting samples of distressed users, focusing on their purpose, methods and the main content viewed. In-depth interviews were conducted in the UK between 2014-2016 with i) young people in the community; and ii) self-harm patients presenting to hospital emergency departments. Data were analysed using methods of constant comparison. Suicide-related internet use varied according to the severity of suicidal feelings. In the young people sample, where severity was lower, use was characterised by disorganised browsing without clear purpose. A range of content was 'stumbled upon' including information about suicide methods. They also pursued opportunities to interact with others and explore online help. Self-harm patients were a higher severity group with a history of suicidal behaviour. Their use was purposeful and strategic, focused around 'researching' suicide methods to maximise effectiveness. They made specific choices about content viewed; many consulting factual content in preference to user generated accounts, while help content and communication was avoided. Findings indicate further action is necessary to improve online safety. Also, novel online help approaches are needed to engage individuals experiencing suicidal crisis. Awareness of the nature of suicide-related internet use and how this may reflect the status of an individual's suicidal thinking could be beneficial to clinicians to promote safety and indicate risk.

Ending the war between Sales & Marketing.

PubMed

Kotler, Philip; Rackham, Neil; Krishnaswamy, Suj

2006-01-01

Sales departments tend to believe that marketers are out of touch with what's really going on in the marketplace. Marketing people, in turn, believe the sales force is myopic--too focused on individual customer experiences, insufficiently aware of the larger market, and blind to the future. In short, each group undervalues the other's contributions. Both stumble (and organizational performance suffers) when they are out of sync. Yet few firms seem to make serious overtures toward analyzing and enhancing the relationship between these two critical functions. Curious about the misalignment between Sales and Marketing, the authors interviewed pairs of chief marketing officers and sales vice presidents to capture their perspectives. They looked in depth at the relationship between Sales and Marketing in a variety of companies in different industries. Their goal was to identify best practices that could enhance the joint performance and increase the contributions of these two functions. Among their findings: The marketing function takes different forms in different companies at different product life cycle stages. Marketing's increasing influence in each phase of an organization's growth profoundly affects its relationship with Sales. The strains between Sales and Marketing fall into two main categories: economic (a single budget is typically divided, between Sales and Marketing, and not always evenly) and cultural (the two functions attract very different types of people who achieve success by spending their time in very different ways). In this article, the authors describe the four types of relationships Sales and Marketing typically exhibit. They provide a diagnostic to help readers assess their companies' level of integration, and they offer recommendations for more closely aligning the two functions.

Comparative study between cold air analgesia and supraorbital and supratrochlear nerve block for the management of pain during photodynamic therapy for actinic keratoses of the frontotemporal zone.

PubMed

Serra-Guillen, C; Hueso, L; Nagore, E; Vila, M; Llombart, B; Requena Caballero, C; Botella-Estrada, R; Sanmartin, O; Alfaro-Rubio, A; Guillen, C

2009-08-01

Photodynamic therapy (PDT) is an effective treatment for actinic keratoses, Bowen's disease and basal cell carcinoma. The main drawback of PDT is pain during application. To compare the efficacy of supratrochlear and supraorbital nerve block with cold air analgesia to control the pain experienced during PDT. A controlled open clinical trial was conducted in 34 patients having multiple actinic keratoses in the frontal region treated with PDT. On one side of the frontal region the supratrochlear and supraorbital nerves were blocked, while on the other side cold air was used as the method of analgesia. Pain was recorded on a visual analogue scale after treatment. Thirty-one of 34 patients reported less pain in the zone treated with nerve block. This difference was statistically significant. Nerve block is superior to cold air and is an easy, safe, effective means of controlling the pain associated with PDT.

Petrographic and geochemical characteristic of volcanic rocks from Tasik Kenyir and Kampung Awah, East Malaya block, Peninsular Malaysia

NASA Astrophysics Data System (ADS)

Roselee, Muhammad Hatta; Umor, Mohd Rozi; Ghani, Azman Abdul; Badruldin, Muhamad Hafifi; Quek, Long Xiang

2018-04-01

Kampung Awah and Tasik Kenyir are geologically located in East Malaya Blocks. These block is also known as western margin of Indochina terrane. Apart from sedimentary formations, East Malaya Blocks is also dominated by plutonic and volcanic rocks of mafic to rhyolitic compositions. Petrography and geochemical data suggest that Kampung Awah and Tasik Kenyir are one of locations which consists of volcanic rocks of generally basaltic to basaltic andesite compositions. Volcanic rocks from both area consists of plagioclcase, clinopyroxene, orthpyroxene as main mineral constituents with minor occurrences of hornblende. Geochemical data also indicate that volcanic rocks from both area were formed during subduction of the Paleo-tethys oceanic underneath the East Malaya Block or Indochina terrane. Most of the samples are metaluminous which indicate the volcanics are derived from igneous origin. This paper will contribute new geochemical data of mafic volcanics from Kampung Awah and Tasik Kenyir with the support of petrographic and field evidence to deduce the magma evolution and the tectonic setting.

Tuning the cache memory usage in tomographic reconstruction on standard computers with Advanced Vector eXtensions (AVX)

PubMed Central

Agulleiro, Jose-Ignacio; Fernandez, Jose-Jesus

2015-01-01

Cache blocking is a technique widely used in scientific computing to minimize the exchange of information with main memory by reusing the data kept in cache memory. In tomographic reconstruction on standard computers using vector instructions, cache blocking turns out to be central to optimize performance. To this end, sinograms of the tilt-series and slices of the volumes to be reconstructed have to be divided into small blocks that fit into the different levels of cache memory. The code is then reorganized so as to operate with a block as much as possible before proceeding with another one. This data article is related to the research article titled Tomo3D 2.0 – Exploitation of Advanced Vector eXtensions (AVX) for 3D reconstruction (Agulleiro and Fernandez, 2015) [1]. Here we present data of a thorough study of the performance of tomographic reconstruction by varying cache block sizes, which allows derivation of expressions for their automatic quasi-optimal tuning. PMID:26217710

Tuning the cache memory usage in tomographic reconstruction on standard computers with Advanced Vector eXtensions (AVX).

PubMed

Agulleiro, Jose-Ignacio; Fernandez, Jose-Jesus

2015-06-01

Cache blocking is a technique widely used in scientific computing to minimize the exchange of information with main memory by reusing the data kept in cache memory. In tomographic reconstruction on standard computers using vector instructions, cache blocking turns out to be central to optimize performance. To this end, sinograms of the tilt-series and slices of the volumes to be reconstructed have to be divided into small blocks that fit into the different levels of cache memory. The code is then reorganized so as to operate with a block as much as possible before proceeding with another one. This data article is related to the research article titled Tomo3D 2.0 - Exploitation of Advanced Vector eXtensions (AVX) for 3D reconstruction (Agulleiro and Fernandez, 2015) [1]. Here we present data of a thorough study of the performance of tomographic reconstruction by varying cache block sizes, which allows derivation of expressions for their automatic quasi-optimal tuning.

[Interest of ultrasonographic guidance in paediatric regional anaesthesia].

PubMed

Dadure, C; Raux, O; Rochette, A; Capdevila, X

2009-10-01

The use of ultrasonographic guidance for regional anaesthesia has known recently a big interest in children in recent years. The linear ultrasound probes with a 25 mm active surface area (or probes with 38 mm active surface area in older children), with high sound frequencies in the range 8-14 MHz, allow a good compromise between excellent resolution for superficial structure and good penetration depths. In children, the easiest ultrasound guided blocks are axillar blocks, femoral blocks, fascia iliaca compartment blocks, ilio-inguinal blocks and para-umbilical blocks, caudal blocks. They permit a safe and easy learning curve of these techniques. The main advantage of ultrasound guided regional anaesthesia is the visualization of different anatomical structures and the approximate localization of the tip of needle. The other advantages for ultrasound guided peripheral nerve blocks in children are: faster onset time of sensory and motor block, longer duration of sensory blockade, increase of blockade quality and reduction of local anesthetic injection. The use of ultrasonographic guidance for central block allows to visualize different structures as well as spine and his content. Spinous process, ligament flavum, dura mater, conus medullaris and cerebrospinal fluid are identifiable, and give some information on spine, epidural space and the depth between epidural space and skin. At last, in caudal block, ultrasounds permit to evaluate the anatomy of caudal epidural space, especially the relation of the sacral hiatus to the dural sac and the search of occult spinal dysraphism. Benefit of this technique is the visualization of targeted nerves or spaces and the spread of injected local anaesthetic.

Impact of Atmospheric Blocking on South America in Austral Summer

NASA Astrophysics Data System (ADS)

Rodrigues, Regina; Woollings, Tim

2017-04-01

In this study, we investigate atmospheric blocking over east South America in austral summer for the period of 1979-2014. Our results show that blocking over this area is a consequence of propagating Rossby waves that grow to large amplitudes and eventually break anticyclonically over subtropical South America (SSA). The SSA blocking can prevent the establishment of the South Atlantic Convergence Zone (SACZ). As such, years with more blocking days coincide with years with fewer SACZ days and reduced precipitation. Convection mainly over the Indian Ocean associated with Madden-Julian Oscillation (MJO) phases 1 and 2 can trigger the wave train that leads to SSA blocking whereas convection over the western/central Pacific associated with phases 6 and 7 is more likely to lead to SACZ events. We find that MJO is a key source of long-term variability in SSA blocking frequency. The wave packets associated with SSA blocking and SACZ episodes differ not only in their origin but also in their phase and refraction pattern. The tropopause-based methodology used here is proven to reliably identify events that lead to extremes of surface temperature and precipitation over SSA. Up to 80% of warm surface air temperature extremes occur simultaneously with SSA blocking events. They are also responsible for the warming of western South Atlantic. The frequency of SSA blocking days is highly anti-correlated with the rainfall over southeast Brazil. The worst droughts in this area, during the summers of 1984, 2001 and 2014, are linked to record high numbers of SSA blocking days. The persistence of these events is also important in generating the extreme impacts.

An outline of graphical Markov models in dentistry.

PubMed

Helfenstein, U; Steiner, M; Menghini, G

1999-12-01

In the usual multiple regression model there is one response variable and one block of several explanatory variables. In contrast, in reality there may be a block of several possibly interacting response variables one would like to explain. In addition, the explanatory variables may split into a sequence of several blocks, each block containing several interacting variables. The variables in the second block are explained by those in the first block; the variables in the third block by those in the first and the second block etc. During recent years methods have been developed allowing analysis of problems where the data set has the above complex structure. The models involved are called graphical models or graphical Markov models. The main result of an analysis is a picture, a conditional independence graph with precise statistical meaning, consisting of circles representing variables and lines or arrows representing significant conditional associations. The absence of a line between two circles signifies that the corresponding two variables are independent conditional on the presence of other variables in the model. An example from epidemiology is presented in order to demonstrate application and use of the models. The data set in the example has a complex structure consisting of successive blocks: the variable in the first block is year of investigation; the variables in the second block are age and gender; the variables in the third block are indices of calculus, gingivitis and mutans streptococci and the final response variables in the fourth block are different indices of caries. Since the statistical methods may not be easily accessible to dentists, this article presents them in an introductory form. Graphical models may be of great value to dentists in allowing analysis and visualisation of complex structured multivariate data sets consisting of a sequence of blocks of interacting variables and, in particular, several possibly interacting responses in the final block.

Savings and load reaps passive solar dividends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-06-01

A wood-burning fireplace is the main backup heating system at the Friendship Federal Savings and Loan office in Butler, Pennsylvania. The solar design consists of a passive system in which a concrete block wall serves as the energy collector for the building. A 14-square meter skylight over part of the main banking lobby provides additional solar energy. (MCW)

An engine awaits processing in the new engine shop at KSC

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Shuttle Main Engine Processing Facility (SSMEPF), a new Block 2A engine sits on the workstand as technicians process it. The engine is scheduled to fly on the Space Shuttle Endeavour during the STS-88 mission in December 1998. The SSMEPF officially opened on July 6, replacing the Shuttle Main Engine Shop.

Teacher Professional Development through a Collaborative Curriculum Project--An Example of TPACK in Maine

ERIC Educational Resources Information Center

Allan, Walter C.; Erickson, Jeryl L.; Brookhouse, Phil; Johnson, Judith L.

2010-01-01

Maine's one-to-one laptop program provides an ideal opportunity to explore conditions that optimize teacher integration of technology-focused curriculum into the classroom. EcoScienceWorks (ESW) is an ecology curriculum that includes targeted simulations and a code block programming challenge developed through an NSF-ITEST grant. The project was…

Lead-isotopic evidence for distinct source of granite and for distinct basement in the northern Appalachians, Maine.

USGS Publications Warehouse

Ayuso, R.A.

1986-01-01

Lead-isotopic compositions of feldspars in high-level Devonian granitic plutons across the northern Appalachians were measured. The presence of three fundamentally different sources of granites was indicated by three distinct lead-isotope groups. Plutons in the coastal lithotectonic block are the most radiogenic (206Pb/204Pb) 18.25-19.25; 207Pb/204Pb 15.59-15.67; 208Pb/204Pb 38.00-38.60); plutons in northern Maine are the least radiogenic (206Pb/204Pb 18.00-18.50; 207Pb/204Pb 15.51-15.55; 208Pb/204Pb 37.80-38.38). Intermediate lead-isotope values characterize the plutons in central Maine. All plutons show relatively radiogenic lead values for their ages and suggest the imprint of continental crustal sources, particularly in the coastal block. These plutons were formed in different crustal fragments in a continental environment, that were juxtaposed after emplacement of the granites.-L.C.H.

Electrical imaging at the large block test—Yucca Mountain, Nevada

NASA Astrophysics Data System (ADS)

Ramirez, A.; Daily, W.

2001-02-01

A monolithic block of densely welded tuff was excavated from a site on Fran Ridge near Yucca Mountain, Nevada so that coupled thermohydrological processes could be studied in a controlled, in situ experiment. A series of heaters were placed in a horizontal plane about 3 m from the top of the 3 m×3 m×4.5-m high block. Temperatures were measured at many points within and on the block surface and a suite of other measurements were taken to define the thermal and hydrologic response. Electrical resistance tomography (ERT) was used to map two-dimensional images of moisture content changes along four planes in the block. The ERT images clearly delineate the drying and wetting of the rockmass during the 13 months of heating and subsequent 6 months of cool down. The main feature is a prominent dry zone that forms around the heaters then gradually disappears as the rock cools down. Other features include linear anomalies of decreasing moisture content, which are fractures dehydrating as the block heats up. There are also examples of compact anomalies of wetting. Some of these appear to be water accumulation in fractures, which are draining condensate from the block. Others may be rainwater entering a fracture at the top of the block. During cool-down, a general rewetting is observed although this is less certain because of poor data quality during this stage of the experiment.

NANOSTRUCTURED METAL OXIDE CATALYSTS VIA BUILDING BLOCK SYNTHESES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craig E. Barnes

2013-03-05

A broadly applicable methodology has been developed to prepare new single site catalysts on silica supports. This methodology requires of three critical components: a rigid building block that will be the main structural and compositional component of the support matrix; a family of linking reagents that will be used to insert active metals into the matrix as well as cross link building blocks into a three dimensional matrix; and a clean coupling reaction that will connect building blocks and linking agents together in a controlled fashion. The final piece of conceptual strategy at the center of this methodology involves dosingmore » the building block with known amounts of linking agents so that the targeted connectivity of a linking center to surrounding building blocks is obtained. Achieving targeted connectivities around catalytically active metals in these building block matrices is a critical element of the strategy by which single site catalysts are obtained. This methodology has been demonstrated with a model system involving only silicon and then with two metal-containing systems (titanium and vanadium). The effect that connectivity has on the reactivity of atomically dispersed titanium sites in silica building block matrices has been investigated in the selective oxidation of phenols to benezoquinones. 2-connected titanium sites are found to be five times as active (i.e. initial turnover frequencies) than 4-connected titanium sites (i.e. framework titanium sites).« less

MR Image Reconstruction Using Block Matching and Adaptive Kernel Methods.

PubMed

Schmidt, Johannes F M; Santelli, Claudio; Kozerke, Sebastian

2016-01-01

An approach to Magnetic Resonance (MR) image reconstruction from undersampled data is proposed. Undersampling artifacts are removed using an iterative thresholding algorithm applied to nonlinearly transformed image block arrays. Each block array is transformed using kernel principal component analysis where the contribution of each image block to the transform depends in a nonlinear fashion on the distance to other image blocks. Elimination of undersampling artifacts is achieved by conventional principal component analysis in the nonlinear transform domain, projection onto the main components and back-mapping into the image domain. Iterative image reconstruction is performed by interleaving the proposed undersampling artifact removal step and gradient updates enforcing consistency with acquired k-space data. The algorithm is evaluated using retrospectively undersampled MR cardiac cine data and compared to k-t SPARSE-SENSE, block matching with spatial Fourier filtering and k-t ℓ1-SPIRiT reconstruction. Evaluation of image quality and root-mean-squared-error (RMSE) reveal improved image reconstruction for up to 8-fold undersampled data with the proposed approach relative to k-t SPARSE-SENSE, block matching with spatial Fourier filtering and k-t ℓ1-SPIRiT. In conclusion, block matching and kernel methods can be used for effective removal of undersampling artifacts in MR image reconstruction and outperform methods using standard compressed sensing and ℓ1-regularized parallel imaging methods.

Blogging for Soil: Why, how and having fun!

NASA Astrophysics Data System (ADS)

Drake, Jess

2014-05-01

Scientific blogging has become a more and more popular way of science outreach and communication. There are only a handful of soil science blogs, and I think there should be more! Blogging is a great way to share cool soil science stories, engage with the wider community, and promote understanding. It allows people to stumble over thoughts and ideas, and to think about how it fits in their daily life. It also provides an informal education and reference on the internet in a time where people Google everything. It can also be fun as well as being factual. At this talk, using my own experiences and the success of other soil science blogs, I will discuss: how to start a blog, why we should consider them as a way to communicate science, and what things to consider when you start your blog.

Eastern Europe: USSR aims to improve production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rigassi, D.A.

1986-08-01

This article details the perspectives for Eastern European petroleum development. Observations include: Oil output in Russia declined 2.6% last year, a drop more than twice as bad as 1984; Gorbachev cleaned house in 1985 after inspecting production problems in West Siberia; USSR exploratory/appraisal drilling the next five years should exceed 1981-85 by 40%; Gas output in USSR for '85 was 57.5 bcfd. A peak of 64 bcfd was reached last February; Poland hit a major offshore oil and gas find in the Baltic Sea during October 1985; Cash-short Yugoslavia plans to develop Ivana offshore gas field in the Adriatic Sea;more » Faced with stumbling domestic oil production, Romania turns to the USSR to fill the gap; Gas production in Hungary may drop despite added production from new and old fields.« less

Preparation of Ceramic-Bonded Carbon Block for Blast Furnace

NASA Astrophysics Data System (ADS)

Li, Yiwei; Li, Yawei; Sang, Shaobai; Chen, Xilai; Zhao, Lei; Li, Yuanbing; Li, Shujing

2014-01-01

Traditional carbon blocks for blast furnaces are mainly produced with electrically calcined anthracite owing to its good hot metal corrosion resistance. However, this kind of material shows low thermal conductivity and does not meet the demands for cooling of the hearth and the bottom of blast furnaces. In this article, a new kind of a high-performance carbon block has been prepared via ceramic-bonded carbon (CBC) technology in a coke bed at 1673 K (1400 °C) using artificial graphite aggregate, alumina, metallic aluminum, and silicon powders as starting materials. The results showed that artificial graphite aggregates were strongly bonded by the three-dimensional network of ceramic phases in carbon blocks. In this case, the good resistance of the CBC blocks against erosion/corrosion by the hot metal is provided by the ceramic matrix and the high thermal conductivity by the graphite aggregates. The microstructure of this carbon block resembles that of CBC composites with a mean pore size of less than 0.1 μm, and up to 90 pct of the porosity shows a pore size <1 μm. Its thermal conductivity is higher than 30 W · m-1 · K-1 [293 K (20 °C)]. Meanwhile, its hot metal corrosion resistance is better than that of traditional carbon blocks.

Two injection digital block versus single subcutaneous palmar injection block for finger lacerations.

PubMed

Okur, O M; Şener, A; Kavakli, H Ş; Çelik, G K; Doğan, N Ö; Içme, F; Günaydin, G P

2017-12-01

We aimed to compare two digital nerve block techniques in patients due to traumatic digital lacerations. This was a randomized-controlled study designed prospectively in the emergency department of a university-based training and research hospital. Randomization was achieved by sealed envelopes. Half of the patients were randomised to traditional (two-injection) digital nerve block technique while single-injection digital nerve block technique was applied to the other half. Score of pain due to anesthetic infiltration and suturing, onset time of total anesthesia, need for an additional rescue injection were the parameters evaluated with both groups. Epinephrin added lidocaine hydrochloride preparation was used for the anesthetic application. Visual analog scale was used for the evaluation of pain scores. Outcomes were compared by using Mann-Whitney U test and Student t-test. Fifty emergency department patients ≥18 years requiring digital nerve block were enrolled in the study. Mean age of the patients was 33 (min-max: 19-86) and 39 (78 %) were male. No statistically significant difference was found between the two groups in terms of our main parameters; anesthesia pain score, suturing pain score, onset time of total anesthesia and rescue injection need. Single injection volar digital nerve block technique is a suitable alternative for digital anesthesias in emergency departments.

A new dry hypothesis for the formation of Martian linear gullies

USGS Publications Warehouse

Diniega, Serina; Hansen, Candice J.; McElwaine, Jim N.; Hugenholtz, C.H.; Dundas, Colin M.; McEwen, Alfred S.; Bourke, Mary C.

2013-01-01

Long, narrow grooves found on the slopes of martian sand dunes have been cited as evidence of liquid water via the hypothesis that melt-water initiated debris flows eroded channels and deposited lateral levées. However, this theory has several short-comings for explaining the observed morphology and activity of these linear gullies. We present an alternative hypothesis that is consistent with the observed morphology, location, and current activity: that blocks of CO2 ice break from over-steepened cornices as sublimation processes destabilize the surface in the spring, and these blocks move downslope, carving out levéed grooves of relatively uniform width and forming terminal pits. To test this hypothesis, we describe experiments involving water and CO2 blocks on terrestrial dunes and then compare results with the martian features. Furthermore, we present a theoretical model of the initiation of block motion due to sublimation and use this to quantitatively compare the expected behavior of blocks on the Earth and Mars. The model demonstrates that CO2 blocks can be expected to move via our proposed mechanism on the Earth and Mars, and the experiments show that the motion of these blocks will naturally create the main morphological features of linear gullies seen on Mars.

Dependence of present and future European heat waves and cold spells on the location of atmospheric blocking

NASA Astrophysics Data System (ADS)

Brunner, L.; Schaller, N.; Sillmann, J.; Steiner, A. K.

2017-12-01

Atmospheric blocking describes stationary anti-cyclones, which weaken or reverse the climatological flow at mid-latitudes. In the northern hemisphere one of the main blocking regions is located over the North Atlantic and Northern Europe. The link between blocking and European temperature extremes, such as heat waves and cold spells, strongly depends on several aspects like season, longitudinal location of the block, and location of the extremes (particularly Northern Europe versus Southern Europe). We use a 50-member ensemble of the Canadian CanESM2 model to investigate historical (1981-2010) and future (2070-2099) blocking cases and their relationship with European temperature extremes. For the historical period the model results are also compared to those from the ERA-Interim reanalysis. Atmospheric blocking is detected on a daily basis in different 30° longitude windows between 60°W and 60°E, using a standard geopotential height-based detection index. Temperature extremes are defined by the daily Heat/Cold Wave Magnitude Index (HWMId/CWMId). The role of cold advection is found particularly important in winter conditions leading to a more than threefold increase in cold wave occurrence during blocking between 60°W and 0°. During blocking over Northern Europe (0° to 60°E) a split relationship is found with cold wave occurrence being strongly increased in Southern Europe, while it is decreased in Northern Europe. Direct, radiative effects dominate in summer, therefore blocking westward of Europe has a weaker effect, while blocking over Northern Europe leads to an increase of heat waves by at least a factor three at the location of the block and a decrease in cold wave occurrence in almost all of Europe. Comparing the historical and future period we find the link between blocking and temperature extremes in Europe to be robust, even though blocking frequency and temperatures are changing.

Perspectives of the KM3NeT project

NASA Astrophysics Data System (ADS)

Margiotta, A.; KM3NeT Collaboration

2016-10-01

KM3NeT is a large distributed research infrastructure that comprises a network of deep-sea neutrino telescopes in the Mediterranean Sea with user ports for Earth and Sea sciences. The main objectives of KM3NeT are the discovery and subsequent observation of high-energy neutrino sources in the Universe (ARCA) and the determination of the mass hierarchy of neutrinos (ORCA). Technically, the network of telescopes will consist of building blocks of 115 vertical detection units anchored at the seabed and connected to shore via a deep sea electro-optical cable. Each detection unit carries 18 optical modules equipped with 31 3; photomultipliers. Two configurations for the building blocks are defined to optimally detect neutrinos in different ranges of energy. The modular technical design of the KM3NeT telescope allows for a progressive implementation and for data taking even with an incomplete detector. The first phase of implementation has started. The next phase foresees the installation of three building blocks: two building blocks, for a total instrumented volume of 1 km3 (ARCA), at the KM3NeT-It site, at a depth of 3500 m, about 100 km offshore Capo Passero, Sicily. The main scientific goals of the ARCA detector is the exploration of the neutrino sky with unprecedented resolution, searching for neutrinos coming from defined sources or sky regions, like the Galactic Plane. It will also look for diffuse high energy neutrino fluxes following the indication provided by the IceCube signal. The third building block, with a more compact distribution of the optical modules, will be deployed at the KM3NeT-Fr site, 40 km offshore Toulon at a depth of 2500 m (ORCA). The main objective of ORCA is studying the neutrino mass-hierarchy problem and exploring the low energy region of the spectrum. The status of the first phase of the KM3NeT implementation is described and a survey of the physics potentiality of the telescope is given in this contribution, with particular emphasis on the high energy studies.

Tharsis block tectonics on Mars

NASA Technical Reports Server (NTRS)

Raitala, Jouko T.

1988-01-01

The concept of block tectonics provides a framework for understanding many aspects of Tharsis and adjoining structures. This Tharsis block tectonics on Mars is manifested partly by mantle-related doming and partly by response to loading by subsequent volcanic construction. Although the origin of the volcanism from beneath Tharsis is a subject of controversy explanations have to include inhomogeneities in Martian internal structure, energy distribution, magma accumulation and motion below the lithosphere. Thermal convection can be seen as a necessary consequence for transient initial phase of Martian cooling. This produced part of the elevated topography with tensional stresses and graben systems radial to the main bulge. The linear grabens, radial to the Tharsis center, can be interpreted to indicate rift zones that define the crustal block boundaries. The load-induced stresses may then have contributed on further graben and ridge formation over an extended period of time.

Mapping of the thermal neutron distribution in the lead block assembly of the PS-211 experiment at CERN, using thermoluminescence and nuclear track detectors.

PubMed

Savvidis, E; Eleftheriadis, C A; Kitis, G

2002-01-01

The main purpose of the TARC (Transmutation by Adiabatic Resonance Crossing) experiment (PS-211), was to demonstrate the possibility to destroy efficiently Long-Lived Fission Fragments (LLFF) in Accelerator Driven Systems (ADS). The experimental set-up which consisted of a lead block with dimensions 3.3 x 3.3 x 3 m3, was installed in a CERN Proton Synchrotron (PS) beam line. The proton beam at 2.5 GeV/c and 3.5 GeV/c, was incident in the centre of the lead block assembly producing neutrons via spallation reactions. In this study, neutron flux measurements are presented in the lead block assembly using thermoluminescence and nuclear track detectors. The results are in good agreement with Monte Carlo calculations as well as with the results of the other methods used in the framework of the TARC experiment.

Statistical Analysis of the Links between Blocking and Nor'easters

NASA Astrophysics Data System (ADS)

Booth, J. F.; Pfahl, S.

2015-12-01

Nor'easters can be loosely defined as extratropical cyclones that develop as they progress northward along the eastern coast of North America. The path makes it possible for these storms to generate storm surge along the coastline and/or heavy precipitation or snow inland. In the present analysis, the path of the storms is investigated relative to the behavior of upstream blocking events over the North Atlantic Ocean. For this analysis, two separate Lagrangian tracking methods are used to identify the extratropical cyclone paths and the blocking events. Using the cyclone paths, Nor'easters are identified and blocking statistics are calculated for the days prior to, during and following the occurrence of the Nor'easters. The path, strength and intensification rates of the cyclones are compared with the strength and location of the blocks. In the event that a Nor'easter occurs, the likelihood of the presence of block at the southeast tip of Greenland is statistically significantly increased, i.e., the presence of a block concurrent with a Nor'easter happens more often than by random coincidence. However no significant link between the strength of the storms and the strength of the block is identified. These results suggest that the presence of the block mainly affects the path of the Nor'easters. On the other hand, in the event of blocking at the southeast tip of Greenland, the likelihood of a Nor'easter, as opposed to a different type of storm is no greater than what one might expect from randomly sampling cyclone tracks. The results confirm a long held understanding in forecast meteorology that upstream blocking is a necessary but not sufficient condition for generating a Nor'easter.

Temporary persistence of conduction block after prolonged kilohertz frequency alternating current on rat sciatic nerve

NASA Astrophysics Data System (ADS)

Bhadra, Narendra; Foldes, Emily; Vrabec, Tina; Kilgore, Kevin; Bhadra, Niloy

2018-02-01

Objective. Application of kilohertz frequency alternating current (KHFAC) waveforms can result in nerve conduction block that is induced in less than a second. Conduction recovers within seconds when KHFAC is applied for about 5-10 min. This study investigated the effect of repeated and prolonged application of KHFAC on rat sciatic nerve with bipolar platinum electrodes. Approach. Varying durations of KHFAC at signal amplitudes for conduction block with intervals of no stimulus were studied. Nerve conduction was monitored by recording peak Gastrocnemius muscle force utilizing stimulation electrodes proximal (PS) and distal (DS) to a blocking electrode. The PS signal traveled through the block zone on the nerve, while the DS went directly to the motor end-plate junction. The PS/DS force ratio provided a measure of conduction patency of the nerve in the block zone. Main results. Conduction recovery times were found to be significantly affected by the cumulative duration of KHFAC application. Peak stimulated muscle force returned to pre-block levels immediately after cessation of KHFAC delivery when it was applied for less than about 15 min. They fell significantly but recovered to near pre-block levels for cumulative stimulus of 50  ±  20 min, for the tested On/Off times and frequencies. Conduction recovered in two phases, an initial fast one (60-80% recovery), followed by a slower phase. No permanent conduction block was seen at the end of the observation period during any experiment. Significance. This carry-over block effect may be exploited to provide continuous conduction block in peripheral nerves without continuous application of KHFAC.

Nordic guidelines for neuraxial blocks in disturbed haemostasis from the Scandinavian Society of Anaesthesiology and Intensive Care Medicine.

PubMed

Breivik, H; Bang, U; Jalonen, J; Vigfússon, G; Alahuhta, S; Lagerkranser, M

2010-01-01

Central neuraxial blocks (CNBs) for surgery and analgesia are an important part of anaesthesia practice in the Nordic countries. More active thromboprophylaxis with potent antihaemostatic drugs has increased the risk of bleeding into the spinal canal. National guidelines for minimizing this risk in patients who benefit from such blocks vary in their recommendations for safe practice. The Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI) appointed a task force of experts to establish a Nordic consensus on recommendations for best clinical practice in providing effective and safe CNBs in patients with an increased risk of bleeding. We performed a literature search and expert evaluation of evidence for (1) the possible benefits of CNBs on the outcome of anaesthesia and surgery, for (2) risks of spinal bleeding from hereditary and acquired bleeding disorders and antihaemostatic drugs used in surgical patients for thromboprophylaxis, for (3) risk evaluation in published case reports, and for (4) recommendations in published national guidelines. Proposals from the taskforce were available for feedback on the SSAI web-page during the summer of 2008. Neuraxial blocks can improve comfort and reduce morbidity (strong evidence) and mortality (moderate evidence) after surgical procedures. Haemostatic disorders, antihaemostatic drugs, anatomical abnormalities of the spine and spinal blood vessels, elderly patients, and renal and hepatic impairment are risk factors for spinal bleeding (strong evidence). Published national guidelines are mainly based on experts' opinions (weak evidence). The task force reached a consensus on Nordic guidelines, mainly based on our experts' opinions, but we acknowledge different practices in heparinization during vascular surgery and peri-operative administration of non-steroidal anti-inflammatory drugs during neuraxial blocks. Experts from the five Nordic countries offer consensus recommendations for safe clinical practice of neuraxial blocks and how to minimize the risks of serious complications from spinal bleeding. A brief version of the recommendations is available on http://www.ssai.info.

The 15 September 1991 pyroclastic flows at Unzen Volcano (Japan): a flow model for associated ash-cloud surges

NASA Astrophysics Data System (ADS)

Fujii, Toshitsugu; Nakada, Setsuya

1999-04-01

Large-scale collapse of a dacite dome in the late afternoon of 15 September 1991 generated a series of pyroclastic-flow events at Unzen Volcano. Pyroclastic flows with a volume of 1×10 6 m 3 (as DRE) descended the northeastern slope of the volcano, changing their courses to the southeast due to topographic control. After they exited a narrow gorge, an ash-cloud surge rushed straight ahead, detaching the main body of the flow that turned and followed the topographic lows to the east. The surge swept the Kita-Kamikoba area, which had been devastated by the previous pyroclastic-flow events, and transported a car as far as 120 m. Following detachment, the surge lost its force after it moved several hundred meters, but maintained a high temperature. The deposits consist of a bottom layer of better-sorted ash (unit 1), a thick layer of block and ash (unit 2), and a thin top layer of fall-out ash (unit 3). Unit 2 overlies unit 1 with an erosional contact. The upper part of unit 2 grades into better-sorted ash. At distal block-and-ash flow deposits, the bottom part of unit 2 also consists of better-sorted ash, and the contact with the unit 1 deposits becomes ambiguous. Video footage of cascading pyroclastic flows during the 1991-1995 eruption, traveling over surfaces without any topographic barriers, revealed that lobes of ash cloud protruded intermittently from the moving head and sides, and that these lobes surged ahead on the ground surface. This fact, together with the inspection by helicopter shortly after the events, suggests that the protruded lobes consisted of better-sorted ash, and resulted in the deposits of unit 1. The highest ash-cloud plume at the Oshigadani valley exit, and the thickest deposition of fall-out ash over Kita-Kamikoba and Ohnokoba, indicate that abundant ash was also produced when the flow passed through a narrow gorge. In the model presented here, the ash clouds from the pyroclastic flows were composed of a basal turbulent current of high concentration (main body), an overriding and intermediate fluidization zone, and an overlying dilute cloud. Release of pressurized gas in lava block pores, due to collisions among blocks and the resulting upward current, caused a zone of fluidization just above the main body. The mixture of gas and ash sorted in the fluidization zone moved ahead and to the side of the main body as a gravitational current, where the ash was deposited as surge deposits. The main body, which had high internal friction and shear near its base, then overran the surge deposits, partially eroding them. When the upward current of gas (fluidization) waned, better-sorted ash suspended in the fluidization zone was deposited on block-and-ash deposits. In the distal places of block-and-ash deposits, unit 2 probably was deposited in non-turbulent fashion without any erosion of the underlying layer (unit 1).

The implementation of binding blocks in the classroom

NASA Astrophysics Data System (ADS)

Wright, A. J.; Willett, H. V.; Beanland, S. R.; Carson, M.; Davies, R. A.; Duffett, G.; Pastore, A.

2017-09-01

We discuss a series of activities for A-level students which can be carried out using the binding blocks three dimensional chart of nuclides. The planned activities cover four main sections which can be linked to the A-level curriculum; nuclear decays (as seen through the different colours on the chart), medical physics (medical isotopes highlighted on the chart), fusion on Earth (binding energy demonstrated through tower heights) and stellar fusion (which has a limit at 56Fe, illustrated by the decreasing tower heights).

An engine awaits processing in the new engine shop at KSC

NASA Technical Reports Server (NTRS)

1998-01-01

In the Space Shuttle Main Engine Processing Facility (SSMEPF), a new Block 2A engine sits on the transport cradle before being moved to the workstand. The engine is scheduled to fly on the Space Shuttle Endeavour during the STS-88 mission in December 1998. The SSMEPF officially opened on July 6, replacing the Shuttle Main Engine Shop.

Assessment of groundwater quality in Kashipur Block, Purulia district, West Bengal

NASA Astrophysics Data System (ADS)

Kundu, Anindita; Nag, S. K.

2018-03-01

Hydrogeochemical investigation of groundwater resources of Kashipur Block, Purulia district, West Bengal has been carried out to assess the water quality for domestic and irrigation uses. Twenty groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids, hardness, major anions (CO3 2-, HCO3 -, Cl-, SO4 2-, F-) and cations (Ca2+, Mg2+, Fe2+, Na+, K+). Study results reveal that the groundwater of the area is mostly acidic in nature. The trend amongst average ionic concentrations of cations and anions is Mg2+ > Ca2+ > Na+ > Fe2+ > K+ and Cl- > HCO3 - > CO3 2- > SO4 2- > F- respectively during the post monsoon whereas the trend for cations and anions are Mg2+ > Ca2+> Na+ > K+ > Fe and Cl- > HCO3 - > SO4 2- > F- > CO3 - in pre monsoon session, respectively. To explore the ionic toxicity of the study area, the derived parameters like sodium adsorption ratio, soluble sodium percentage, residual sodium carbonate, magnesium adsorption ratio, Kelly's ratio and permeability index were calculated. The hydro geochemical data suggest that weathering of rock forming minerals along with secondary contributions from agricultural and anthropogenic sources are mainly controlling the groundwater composition of Kashipur Block, Purulia District. According to piper diagram, water samples of most of the area of the block are fresh water and in some areas sulphate rich throughout the year. All samples are distributed to central rock dominance category. Groundwater chemistry of this block is mainly controlled by the interaction existing between the litho units and the percolating water into the subsurface domain. However, the groundwater quality and suitability of this study area can be termed as good to moderate with a few exceptions which have been encountered on a local scale.

Intelligibility of emotional speech in younger and older adults.

PubMed

Dupuis, Kate; Pichora-Fuller, M Kathleen

2014-01-01

Little is known about the influence of vocal emotions on speech understanding. Word recognition accuracy for stimuli spoken to portray seven emotions (anger, disgust, fear, sadness, neutral, happiness, and pleasant surprise) was tested in younger and older listeners. Emotions were presented in either mixed (heterogeneous emotions mixed in a list) or blocked (homogeneous emotion blocked in a list) conditions. Three main hypotheses were tested. First, vocal emotion affects word recognition accuracy; specifically, portrayals of fear enhance word recognition accuracy because listeners orient to threatening information and/or distinctive acoustical cues such as high pitch mean and variation. Second, older listeners recognize words less accurately than younger listeners, but the effects of different emotions on intelligibility are similar across age groups. Third, blocking emotions in list results in better word recognition accuracy, especially for older listeners, and reduces the effect of emotion on intelligibility because as listeners develop expectations about vocal emotion, the allocation of processing resources can shift from emotional to lexical processing. Emotion was the within-subjects variable: all participants heard speech stimuli consisting of a carrier phrase followed by a target word spoken by either a younger or an older talker, with an equal number of stimuli portraying each of seven vocal emotions. The speech was presented in multi-talker babble at signal to noise ratios adjusted for each talker and each listener age group. Listener age (younger, older), condition (mixed, blocked), and talker (younger, older) were the main between-subjects variables. Fifty-six students (Mage= 18.3 years) were recruited from an undergraduate psychology course; 56 older adults (Mage= 72.3 years) were recruited from a volunteer pool. All participants had clinically normal pure-tone audiometric thresholds at frequencies ≤3000 Hz. There were significant main effects of emotion, listener age group, and condition on the accuracy of word recognition in noise. Stimuli spoken in a fearful voice were the most intelligible, while those spoken in a sad voice were the least intelligible. Overall, word recognition accuracy was poorer for older than younger adults, but there was no main effect of talker, and the pattern of the effects of different emotions on intelligibility did not differ significantly across age groups. Acoustical analyses helped elucidate the effect of emotion and some intertalker differences. Finally, all participants performed better when emotions were blocked. For both groups, performance improved over repeated presentations of each emotion in both blocked and mixed conditions. These results are the first to demonstrate a relationship between vocal emotion and word recognition accuracy in noise for younger and older listeners. In particular, the enhancement of intelligibility by emotion is greatest for words spoken to portray fear and presented heterogeneously with other emotions. Fear may have a specialized role in orienting attention to words heard in noise. This finding may be an auditory counterpart to the enhanced detection of threat information in visual displays. The effect of vocal emotion on word recognition accuracy is preserved in older listeners with good audiograms and both age groups benefit from blocking and the repetition of emotions.

Seismic geomorphology of the Lobed-channel System of Upper Miocene Huangliu Formation, Yinggehai Basin, Northwestern South China Sea

NASA Astrophysics Data System (ADS)

Liu, H.

2016-02-01

Three-dimensional seismic data have been widely used in interpreting ancient river systems and their associated sediment deposits. Thin-bed reservoirs of lobed-channel system in lithostratigraphic units of Dongfang (DF) area are one of the major study areas for reservoir growth in the Yinggehai basin of northwestern South China Sea. Although it is understood that the transport mechanics of parent substrate and alluvium determine the morphology of channel for lobed-channel system, the transport mechanism and regional gradient are relatively poorly understood. This study is focused on the application of various techniques in seismic geomorphology to the Yinggehai Basin at paleo-water-depth of 120m to assess influences of regional gradient and relative sea level change on lobed-channel palaeogeomorphology in shallow-water environments. The Vietnam paleo-Blue River, which located at south of modern Red River, flowed through DF area and transported turbidity deposit to DF area in the coastal environment. In 3-D seismic survey area, four fifth-order sequences in first member of upper Miocene Huangliu formation were identified using well and seismic data. Seismic inversion and 90° phasing of seismic data were used to convert seismic traces to pseudolithologic logs. Stratal slicing made it possible to interpolate and extrapolate well-data-derived sequence and identify submarine fan, channel fill, lobes and overbank deposit. Strata slices suggested that sea-floor slopes exerted main influence on channel morphology. Specifically, DF13-1 block had high gradient, which mainly distributed mud-sand-rich lobes. However, DF13-2 block established low gradient, which mostly indicated sand-rich braided channels. The values of sinuosity, channel widths, meander-belt widths in DF13-2 block are all greater than these in DF13-1 block. In addition, results of carbon isotope measurements and foraminiferal research of two blocks suggest that paleo sea level in DF13-2 block (30m 150m) was higher than that of DF13-1 block (20m 90m). It also deciphered why channels in DF13-2 incised deeply because of the stronger hydrodynamic energy in the shallow-water environments. Thus DF13-2 block was formed in a lobed-channel and sand rich system, compared with DF13-1 of channelized-lobes and mud-sand rich system.

Interaction between FKBP5 gene and childhood trauma on psychosis, depression and anxiety symptoms in a non-clinical sample.

PubMed

de Castro-Catala, Marta; Peña, Elionora; Kwapil, Thomas R; Papiol, Sergi; Sheinbaum, Tamara; Cristóbal-Narváez, Paula; Ballespí, Sergi; Barrantes-Vidal, Neus; Rosa, Araceli

2017-11-01

Childhood trauma has been associated with a heightened risk for presenting clinical and non-clinical psychopathology in adulthood. Genes related with the stress response, such as the FK506 binding protein 51 (FKBP5), are plausible candidates moderating the effects of childhood trauma on the emergence of such symptoms later on. The present study aimed to explore the moderating role of FKBP5 genetic variability on the association of different types of childhood trauma with subclinical psychosis, depression and anxiety in a non-clinical sample. Schizotypy, psychotic-like experiences, depression and anxiety symptoms and childhood trauma were assessed in 808 young adults. Two FKBP5 haplotypic blocks were detected: block 1 (rs3800373 - rs9296158 - rs1360780) and block 2 (rs9470080 - rs4713916). Subjects were classified in two groups according to whether they carried or not the risk haplotype previously described in the literature (block 1: CAT and block 2: TA). Linear regression analyses were used to study (i) the main effects of childhood trauma and FKBP5 haplotype blocks and (ii) their interaction effects on the mentioned forms of psychopathology. All childhood trauma scales, except sexual abuse, were associated with schizotypy, psychotic-like experiences, depression and anxiety symptoms. None of the analysed symptoms was associated with the main effects of FKBP5 genetic variability. However an interaction effect between block 1 and physical abuse was observed on anxiety, with lower scores in CAT carriers. This effect was driven by SNP 1 and 2. Moreover, an interaction effect between block 2 and physical abuse was identified on the variables tapping depressive and anxiety symptoms. Specifically, non-TA carrier subjects who were exposed to physical abuse were found to be at higher risk for depressive and anxiety symptoms. These effects were driven by SNP 5. No interaction effect was observed for the other variables. Our data suggest that exposure to childhood physical abuse may increase the risk for sub-clinical depressive and anxiety symptoms depending on FKBP5 genetic variability. Further research is needed to better elucidate the role of FKBP5 on mental health in clinical and non-clinical cohorts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Geological and Geophysical Integration Regarding a Structural Evolution Modelling of a Suture Zone Controlled by a Cratonic Buttress - The Case of Dom Feliciano Orogenic Belt, SSE Brazil, Implications for Western Gondwana Assembly

NASA Astrophysics Data System (ADS)

Bruno, H.; Almeida, J.; Heilbron, M. C. P. L.; Salomão, M.

2017-12-01

The matters surrounding the amalgamation of tectonic blocks during the Brasiliano / Pan-African orogeny have been the main subject of study of several works in recent years. The main objective of this work is the hierarchy and discrimination of the boundaries between the known tectonic blocks, integrating geological and geophysical data. The geology of the study area is dominated by Precambrian terranes; Luís Alves Terrane, the vulcanosedimentary sequences of the Itajaí and Campo Alegre Basins, the metasedimentary sequences of the Brusque and Paranaguá Terranes and their granitic suites besides the granitoids of the Florianópolis Terrane. The shear zones and faults that separate these crustal blocks were developed during the Brasiliano / Pan-African orogenic cycle that led to the formation of the supercontinent Gondwana. These tectonic boundaries generally separate blocks of different rheology and crustal thickness. The integration of geological and geophysical data allowed the identification of important structural lineaments and crustal boundaries. The presented geodynamic model suggests that the suture between the block composed of the Brusque, Paranaguá and Florianópolis Terranes and the block composed by the Luís Alves Terrane is the Itajaí Perimbó Shear Zone, and not the Major Gercino Shear Zone as previously suggested. Considering the Itajaí Perimbó Shear Zone as the suture zone, the metassediments of the Brusque Terrane were deposited on the basement of the Florianópolis Terrane, hereby declared as part of the Angola Craton, and are correlated to the metassediments of the Paranaguá Terrane as a passive margin that in approximately ca. 650 My became active margin, functioning as a forearc basin. The oblique collision between the blocks would have occurred with the development of a dextral transpression in the Itajaí Perimbó Shear Zone, separating the Luís Alves Terrane from the Brusque Terrane, a sinistral transcurrence represented by the Palmital Shear Zone separating the Luís Alves Terrane from the Paranaguá Terrane and a frontal thrust, represented by the Icapara and Serra Negra Shear Zones, separating the already amalgamated block from the Luís Alves and Curitiba Terranes of the Paranaguá Terrane.

User’s Manual for the Ride Motion Simulator

DTIC Science & Technology

1989-08-01

1800 psi). Step 16. Pressurize the system by moving the main pressure switch to "ON." Wait for the roll, pitch, and yaw error signals to go to "Zero...Carefully, help the test subject dismount. Step 41. Flip the main pressure switch on the hydraulic control panel to "OFF." This will block hydraulic...1.13, thus lowering the seat. Release the "Low Limit Override" switch. Step 5. Dismount the test subject. Step 6. Move the main pressure switch to the

Safety Assessment of TACOM’s Ride Motion Simulator

DTIC Science & Technology

1990-01-24

level (1300 to 1800 psi). 24 Step 16. Pressurize the system by moving the main pressure switch to "ON." Wait for the roll, pitch, and yaw error signals...the appropriate seat/shoulder/safety belts and harnesses. Carefully, help the test subject dismount. Step 41. Flip the main pressure switch on the...Dismount the test subject. Step 6. Move the main pressure switch to the "OFF" position. This will block any hydraulic flow to the system. Step 7. Move the

Deconstructing Building Blocks: Preschoolers' Spatial Assembly Performance Relates to Early Mathematics Skills

PubMed Central

Verdine, Brian N.; Golinkoff, Roberta Michnick; Hirsh-Pasek, Kathryn; Newcombe, Nora S.; Filipowicz, Andrew T.; Chang, Alicia

2013-01-01

This study focuses on three main goals: First, 3-year-olds' spatial assembly skills are probed using interlocking block constructions (N = 102). A detailed scoring scheme provides insight into early spatial processing and offers information beyond a basic accuracy score. Second, the relation of spatial assembly to early mathematics skills was evaluated. Spatial skill independently predicted a significant amount of the variability in concurrent mathematics performance. Finally, the relationship between spatial assembly skill and socioeconomic status, gender, and parent-reported spatial language was examined. While children's performance did not differ by gender, lower-SES children were already lagging behind higher-SES children in block assembly. Furthermore, lower-SES parents reported using significantly fewer spatial words with their children. PMID:24112041

Refining the GPS Space Service Volume (SSV) and Building a Multi-GNSS SSV

NASA Technical Reports Server (NTRS)

Parker, Joel J. K.

2017-01-01

The GPS (Global Positioning System) Space Service Volume (SSV) was first defined to protect the GPS main lobe signals from changes from block to block. First developed as a concept by NASA in 2000, it has been adopted for the GPS III block of satellites, and is being used well beyond the current specification to enable increased navigation performance for key missions like GOES-R. NASA has engaged the US IFOR (Interagency Forum Operational Requirements) process to adopt a revised requirement to protect this increased and emerging use. Also, NASA is working through the UN International Committee on GNSS (Global Navigation Satellite System) to develop an interoperable multi-GNSS SSV in partnership with all of the foreign GNSS providers.

A spring-block analogy for the dynamics of stock indexes

NASA Astrophysics Data System (ADS)

Sándor, Bulcsú; Néda, Zoltán

2015-06-01

A spring-block chain placed on a running conveyor belt is considered for modeling stylized facts observed in the dynamics of stock indexes. Individual stocks are modeled by the blocks, while the stock-stock correlations are introduced via simple elastic forces acting in the springs. The dragging effect of the moving belt corresponds to the expected economic growth. The spring-block system produces collective behavior and avalanche like phenomena, similar to the ones observed in stock markets. An artificial index is defined for the spring-block chain, and its dynamics is compared with the one measured for the Dow Jones Industrial Average. For certain parameter regions the model reproduces qualitatively well the dynamics of the logarithmic index, the logarithmic returns, the distribution of the logarithmic returns, the avalanche-size distribution and the distribution of the investment horizons. A noticeable success of the model is that it is able to account for the gain-loss asymmetry observed in the inverse statistics. Our approach has mainly a pedagogical value, bridging between a complex socio-economic phenomena and a basic (mechanical) model in physics.

Estimating natural recharge in San Gorgonio Pass watersheds, California, 1913–2012

USGS Publications Warehouse

Hevesi, Joseph A.; Christensen, Allen H.

2015-12-21

The SGPWM was used to simulate a 100-year water budget, including recharge and runoff, for water years 1913 through 2012. Results indicated that most recharge came from episodic infiltration of surface-water runoff in the larger stream channels. Results also indicated periods of great variability in recharge and runoff in response to variability in precipitation. More recharge was simulated for the area of the groundwater basin underlying the more permeable alluvial fill of the valley floor compared to recharge in the neighboring upland areas of the less permeable mountain blocks. The greater recharge was in response to the episodic streamflow that discharged from the mountain block areas and quickly infiltrated the permeable alluvial fill of the groundwater basin. Although precipitation at the higher altitudes of the mountain block was more than double precipitation at the lower altitudes of the valley floor, recharge for inter-channel areas of the mountain block was limited by the lower permeability bedrock underlying the thin soil cover, and most of the recharge in the mountain block was limited to the main stream channels underlain by alluvial fill.

Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs.

PubMed

Bühler, Mira; Vollstädt-Klein, Sabine; Klemen, Jane; Smolka, Michael N

2008-07-22

Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA) 19, 37, 48), parietal areas (BA 7, 40) and areas in the frontal lobe (BA 6, 44). Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli.Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal.

Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs

PubMed Central

Bühler, Mira; Vollstädt-Klein, Sabine; Klemen, Jane; Smolka, Michael N

2008-01-01

Background Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. Methods To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. Results Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA) 19, 37, 48), parietal areas (BA 7, 40) and areas in the frontal lobe (BA 6, 44). Conclusion Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli. Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal. PMID:18647397

3. DOWNHILL SIDE AND END ELEVATION OF COAL POCKETS, WITH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DOWNHILL SIDE AND END ELEVATION OF COAL POCKETS, WITH RETAINING WALL IN BACKGROUND. VIEW LOOKING NORTHEAST. - Honesdale Coal Pockets, Main & Commercial Streets, between 700 & 800 blocks, Honesdale, Wayne County, PA

Closet located in the east wall to the south of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Closet located in the east wall to the south of the fireplace, northeast second-floor room, main block. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

Adaptive EAGLE dynamic solution adaptation and grid quality enhancement

NASA Technical Reports Server (NTRS)

Luong, Phu Vinh; Thompson, J. F.; Gatlin, B.; Mastin, C. W.; Kim, H. J.

1992-01-01

In the effort described here, the elliptic grid generation procedure in the EAGLE grid code was separated from the main code into a subroutine, and a new subroutine which evaluates several grid quality measures at each grid point was added. The elliptic grid routine can now be called, either by a computational fluid dynamics (CFD) code to generate a new adaptive grid based on flow variables and quality measures through multiple adaptation, or by the EAGLE main code to generate a grid based on quality measure variables through static adaptation. Arrays of flow variables can be read into the EAGLE grid code for use in static adaptation as well. These major changes in the EAGLE adaptive grid system make it easier to convert any CFD code that operates on a block-structured grid (or single-block grid) into a multiple adaptive code.

Final report on COOMET Vickers PTB/VNIIFTRI key comparison (COOMET.M.H-K1.b and COOMET.M.H-K1.c)

NASA Astrophysics Data System (ADS)

Aslanyan, E.; Herrmann, K.

2013-01-01

This report describes a COOMET key comparison on Vickers hardness scales of two National Metrology Institutes—PTB and VNIIFTRI. The pilot laboratory was PTB, which was the linking institute with the key comparison reference values of CCM.H-K1. In the key comparison two sets of hardness reference blocks for the Vickers hardness scales HV1 and HV30, each consisting of three hardness reference blocks with the hardness levels 240 HV, 540 HV and 840 HV, are used. The same hardness reference blocks were used previously in the key comparison CCM.H-K1. The measurement results and uncertainty assessments, announced by VNIIFTRI, are in good agreement with the key comparison reference values of CCM.H-K1. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Domino structures evolution in strike-slip shear zones; the importance of the cataclastic flow

NASA Astrophysics Data System (ADS)

Moreira, N.; Dias, R.

2018-05-01

The Porto-Tomar-Ferreira do Alentejo dextral Shear Zone is one of the most important structures of the Iberian Variscides. In its vicinity, close to Abrantes (Central Portugal), a localized heterogeneous strain pattern developed in a decimetric metamorphic siliceous multilayer. This complex pattern was induced by the D2 dextral shearing of the early S0//S1 foliation in brittle-ductile conditions, giving rise to three main shear zone families. One of these families, with antithetic kinematics, delimits blocks with rigid clockwise rotation surrounded by coeval cataclasites, generating a local domino structure. The proposed geometrical and kinematic analysis, coupled with statistical studies, highlights the relation between subsidiary shear zones and the main shear zone. Despite the heterogeneous strain pattern, a quantitative approach of finite strain was applied based on the restoration of the initial fracture pattern. This approach shows the importance of the cataclastic flow coupled with the translational displacement of the domino domain in solving space problems related to the rigid block rotation. Such processes are key in allowing the rigid block rotation inside shear zones whenever the simple shear component is a fundamental mechanism.

Design and status of the detector block for the ISO-SWS

NASA Technical Reports Server (NTRS)

Luinge, W.; Beintema, D. A.; Haser, L.; Katterloher, R.; Ploeger, G.

1989-01-01

The Short Wave Spectrometer (SWS) is one of the two spectrometers for the Infrared Space Observatory (ISO). It consists of a pair of grating spectrometers and a Fabry-Perot interferometer. Together, the grating spectrometers cover the wavelength range 2.4 to 45 microns, at a resolution between 1000 and 2000. The Fabry-Perot interferometer, in series with one of the grating spectrometers, provides a resolution of about 20,000 at the wavelengths between 15 and 35 microns. The SWS is being built by the Space Research Organization of the Netherlands and the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. The spectrometer has 52 discrete detectors, most of which are bulk detectors. In the design of the spectrometer, the main emphasis is on the sensitivity of the individual channels, rather than on the number of detectors. This was one of the main reasons to select non-destructive read-out circuits, with a separate heated-JFET pre-amplifier for each individual detector. The signals are amplified and filtered in parallel. The engineering tests on the SWS detector block have not yet been completed. The design of the detector block is described and the present problem areas are indicated.

A comparison between the blocking actions of 2-(4-phenylpiperidino) cyclohexanol (AH 5183) and its N-methyl quaternary analogue (AH 5954)

PubMed Central

Marshall, I. G.

1970-01-01

1. The neuromuscular blocking activities of AH 5183 (2-(4-phenylpiperidino) cyclohexanol) and its N-methyl quaternary analogue (AH 5954) were compared in rapidly stimulated nerve-skeletal muscle preparations of the rat, chicken and cat. 2. The evidence indicated that in isolated preparations the neuromuscular block produced by both AH 5183 and AH 5954 was primarily pre-junctional in origin. That produced by AH 5954 was readily reversible either by washing the tissue or by reducing the stimulation frequency, whereas that produced by AH 5183 was difficult to reverse in these ways. 3. Low doses of AH 5954 sensitized the rat hemidiaphragm preparation to the neuromuscular blocking action of choline. The neuromuscular block produced by choline was reversible by tetraethylammonium but not by neostigmine. This suggested that the blocking action of choline is at least partly pre-junctional in nature. 4. In anaesthetized cats AH 5954 possessed a biphasic neuromuscular blocking action. The initial phase was rapid in onset, suggestive of a post-junctional action, whereas the second phase was prolonged and reversible by choline, suggestive of a prejunctional inhibitory action on the choline transport mechanism. AH 5183 produced no initial blocking action and was irreversible by choline. 5. Both AH 5183 and AH 5954 possessed local anaesthetic and α-adrenoceptor blocking actions. These actions and the neuromuscular blocking action were affected to different degrees by quaternization, suggesting that the three main actions of the two drugs are independent. 6. It was concluded that AH 5954 and AH 5183 act at different pre-junctional sites at the neuromuscular junction, AH 5954 acting extraneuronally by inhibiting choline transport and AH 5183 intraneuronally at the level of the synaptic vesicle membrane. PMID:4395087

The contribution of cell blocks in the diagnosis of mediastinal masses and hilar adenopathy samples from echobronchoscopy.

PubMed

Lourido-Cebreiro, Tamara; Leiro-Fernández, Virginia; Tardio-Baiges, Antoni; Botana-Rial, Maribel; Núñez-Delgado, Manuel; Álvarez-Martín, M Jesús; Fernández-Villar, Alberto

2014-07-01

Cell block material from puncture can be obtained with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in many cases. The aim of this study was to analyse the value of additional information from cell blocks obtained with EBUS-TBNA samples from mediastinal and hilar lymph nodes and masses. Review of pathology reports with a specific diagnosis obtained from EBUS-TBNA samples of mediastinal or hilar lesions, prospectively obtained over a two-year period. The generation of cell blocks from cytology needle samples, the contribution to morphological diagnosis, and the possible use of samples for immunohistochemistry were analysed. One hundred and twenty-nine samples corresponding to 110 patients were reviewed. The diagnosis was lung cancer in 81% of cases, extrapulmonary carcinoma in 10%, sarcoidosis in 4%, lymphoma in 2.7%, and tuberculosis in 0.9%. Cell blocks could be obtained in 72% of cases. Immunohistochemistry studies on the cell blocks were significantly easier to perform than on conventional smears (52.6% vs. 14%, P<.0001). In 4cases, the cell block provided an exclusive morphological diagnosis (3sarcoidosis and one metastasis from prostatic carcinoma) and in 3carcinomas, subtype and origin could be identified. Exclusive diagnoses from the cell block were significantly more frequent in benign disease than in malignant disease (25% vs 0.9%, P=.002). Cell blocks were obtained from 72% of EBUS-TBNA diagnostic procedures. The main contributions of cell blocks to pathology examinations were the possibility of carrying out immunohistochemical staining for the better classification of neoplasms, especially extrapulmonary metastatic tumours, and the improved diagnosis of benign lesions. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.

Investigating the impact of atmospheric blocking on temperature extremes across Europe using an objective index

NASA Astrophysics Data System (ADS)

Brunner, Lukas; Steiner, Andrea; Sillmann, Jana

2017-04-01

Atmospheric blocking is a key contributor to European temperature extremes. It leads to stable, long-lasting weather patterns, which favor the development of cold and warm spells. The link between blocking and such temperature extremes differs significantly across Europe. In northern Europe a majority of warm spells are connected to blocking, while cold spells are suppressed during blocked conditions. In southern Europe the opposite picture arises with most cold spells occurring during blocking and warm spells suppressed. Building on earlier work by Brunner et al. (2017) this study aims at a better understanding of the connection between blocking and temperature extremes in Europe. We investigate cold and warm spells with and without blocking in observations from the European daily high-resolution gridded dataset (E-OBS) from 1979 to 2015. We use an objective extreme index (Russo et al. 2015) to identify and compare cold and warm spells across Europe. Our work is lead by the main question: Are cold/warm spells coinciding with blocking different from cold/warm spells during unblocked conditions in regard to duration, extend, or amplitude? Here we present our research question and the study setup, and show first results of our analysis on European temperature extremes. Brunner, L., G. Hegerl, and A. Steiner (2017): Connecting Atmospheric Blocking to European Temperature Extremes in Spring. J. Climate, 30, 585-594, doi: 10.1175/JCLI-D-16-0518.1. Russo, S., J. Sillmann, and E. M. Fischer (2015): Top ten European heatwaves since 1950 and their occurrence in the coming decades. Environ. Res. Lett. 10.12, S. 124003. doi: 10.1088/1748-9326/10/12/124003.

Discovery of the early Jurassic Gajia mélange in the Bangong-Nujiang suture zone: Southward subduction of the Bangong-Nujiang Ocean?

NASA Astrophysics Data System (ADS)

Lai, Wen; Hu, Xiumian; Zhu, Dicheng; An, Wei; Ma, Anlin

2017-06-01

Mélange records a series of geological processes associated with oceanic subduction and continental collision. This paper reports for the first time the presence of Early Jurassic mélange from NW Nagqu in the southern margin of the Bangong-Nujiang suture zone, termed as the Gajia mélange. It shows typically blocks-in-matrix structure with matrix of black shale and siliceous mudstone, and several centimeters to several meters sized blocks of sandstone, silicalite, limestone and basalt. The sandstone blocks consist of homologous sandstone and two types of exotic sandstone, with different modal compositions. The Group 1 of exotic sandstone blocks consists of mainly of feldspar and quartz, whereas the Group 2 is rich in volcanic detritus. The Group 3 of homologous sandstone blocks is rich in feldspar and volcanic detritus with rare occurrence of quartz. U-Pb age data and in situ Hf isotopic compositions of detrital zircons from sandstone blocks are similar to those from the Lhasa terrane, suggesting that the sandstone blocks in the Gajia mélange most probably came from the Lhasa terrane. The YC1σ(2+) age of homologous sandstone blocks is 177 ± 2.4 Ma, suggesting an Early Jurassic depositional age for the sandstones within the Gajia mélange. The Gajia mélange likely records the southward subduction of the Bangong-Nujiang Ocean during the Early Jurassic.

Effect of an alpha-blocker (Nicergoline) and of a beta-blocker (Acebutolol) on the in vitro biosynthesis of vascular extracellular matrix.

PubMed

Moczar, M; Robert, A M; Jacotot, B; Robert, L

2001-05-01

The effect of an alpha-blocking agent and of a beta-blocking agent on the biosynthesis of extracellular matrix macromolecules of the arterial wall was investigated. Rabbit aorta explants were cultured up to 48 hours with radioactive proline, lysine or glucosamine. In presence of these drugs, at concentration shown to be effective for the inhibition of platelet-endothelial cell interactions (10(-7) M), the incorporation of 14C proline in total macromolecular proline was higher than in macromolecular hydroxyproline suggesting a relatively higher rate of biosynthesis of non-collagenous proteins as compared to collagens. The alpha-blocking increased the incorporation of 14C proline in collagenous and non-collagenous proteins after 18 hours of incubation. beta-blocking also increased the incorporation of proline in macromolecular proline and hydroxyproline as compared to control cultures. Both increased the incorporation of 3H glucosamine in newly synthesised glycosaminoglycans. beta-blocking increased mainly the neosynthesis of heparan sulphate, alpha-blocking that of hyaluronan. The incorporation of 14C-lysine in crosslinked, insoluble elastin was not modified. These experiments confirm that alpha and beta-blocking agents can influence not only the tonus of aortic smooth muscle cells but also the relative rates of biosynthesis of extracellular matrix macromolecules. This effect should be taken in consideration for the evaluation of the long range effect of alpha and beta-blocking drugs on the vascular wall.

Effective blocking of the white enhancer requires cooperation between two main mechanisms suggested for the insulator function.

PubMed

Kyrchanova, Olga; Maksimenko, Oksana; Stakhov, Viacheslav; Ivlieva, Tatyana; Parshikov, Alexander; Studitsky, Vasily M; Georgiev, Pavel

2013-01-01

Chromatin insulators block the action of transcriptional enhancers when interposed between an enhancer and a promoter. In this study, we examined the role of chromatin loops formed by two unrelated insulators, gypsy and Fab-7, in their enhancer-blocking activity. To test for this activity, we selected the white reporter gene that is activated by the eye-specific enhancer. The results showed that one copy of the gypsy or Fab-7 insulator failed to block the eye enhancer in most of genomic sites, whereas a chromatin loop formed by two gypsy insulators flanking either the eye enhancer or the reporter completely blocked white stimulation by the enhancer. However, strong enhancer blocking was achieved due not only to chromatin loop formation but also to the direct interaction of the gypsy insulator with the eye enhancer, which was confirmed by the 3C assay. In particular, it was observed that Mod(mdg4)-67.2, a component of the gypsy insulator, interacted with the Zeste protein, which is critical for the eye enhancer-white promoter communication. These results suggest that efficient enhancer blocking depends on the combination of two factors: chromatin loop formation by paired insulators, which generates physical constraints for enhancer-promoter communication, and the direct interaction of proteins recruited to an insulator and to the enhancer-promoter pair.

Effective Blocking of the White Enhancer Requires Cooperation between Two Main Mechanisms Suggested for the Insulator Function

PubMed Central

Stakhov, Viacheslav; Ivlieva, Tatyana; Parshikov, Alexander; Studitsky, Vasily M.; Georgiev, Pavel

2013-01-01

Chromatin insulators block the action of transcriptional enhancers when interposed between an enhancer and a promoter. In this study, we examined the role of chromatin loops formed by two unrelated insulators, gypsy and Fab-7, in their enhancer-blocking activity. To test for this activity, we selected the white reporter gene that is activated by the eye-specific enhancer. The results showed that one copy of the gypsy or Fab-7 insulator failed to block the eye enhancer in most of genomic sites, whereas a chromatin loop formed by two gypsy insulators flanking either the eye enhancer or the reporter completely blocked white stimulation by the enhancer. However, strong enhancer blocking was achieved due not only to chromatin loop formation but also to the direct interaction of the gypsy insulator with the eye enhancer, which was confirmed by the 3C assay. In particular, it was observed that Mod(mdg4)-67.2, a component of the gypsy insulator, interacted with the Zeste protein, which is critical for the eye enhancer–white promoter communication. These results suggest that efficient enhancer blocking depends on the combination of two factors: chromatin loop formation by paired insulators, which generates physical constraints for enhancer–promoter communication, and the direct interaction of proteins recruited to an insulator and to the enhancer–promoter pair. PMID:23861668

Persistence of Amygdala-Hippocampal Connectivity and Multi-Voxel Correlation Structures During Awake Rest After Fear Learning Predicts Long-Term Expression of Fear.

PubMed

Hermans, Erno J; Kanen, Jonathan W; Tambini, Arielle; Fernández, Guillén; Davachi, Lila; Phelps, Elizabeth A

2017-05-01

After encoding, memories undergo a process of consolidation that determines long-term retention. For conditioned fear, animal models postulate that consolidation involves reactivations of neuronal assemblies supporting fear learning during postlearning "offline" periods. However, no human studies to date have investigated such processes, particularly in relation to long-term expression of fear. We tested 24 participants using functional MRI on 2 consecutive days in a fear conditioning paradigm involving 1 habituation block, 2 acquisition blocks, and 2 extinction blocks on day 1, and 2 re-extinction blocks on day 2. Conditioning blocks were preceded and followed by 4.5-min rest blocks. Strength of spontaneous recovery of fear on day 2 served as a measure of long-term expression of fear. Amygdala connectivity primarily with hippocampus increased progressively during postacquisition and postextinction rest on day 1. Intraregional multi-voxel correlation structures within amygdala and hippocampus sampled during a block of differential fear conditioning furthermore persisted after fear learning. Critically, both these main findings were stronger in participants who exhibited spontaneous recovery 24 h later. Our findings indicate that neural circuits activated during fear conditioning exhibit persistent postlearning activity that may be functionally relevant in promoting consolidation of the fear memory. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Power structure among the actors of financial support to the poor to access health services: Social network analysis approach.

PubMed

Etemadi, Manal; Gorji, Hasan Abolghasem; Kangarani, Hannaneh Mohammadi; Ashtarian, Kioomars

2017-12-01

The extent of universal health coverage in terms of financial protection is worrisome in Iran. There are challenges in health policies to guarantee financial accessibility to health services, especially for poor people. Various institutions offer support to ensure that the poor have financial access to health services. The aim of this study is to investigate the relationship network among the institutions active in this field. This study is a policy document analysis. It evaluates the country's legal documents in the field of financial support to the poor for healthcare after the Islamic Revolution in Iran. The researchers looked for the documents on the related websites and referred to the related organizations. The social network analysis approach was chosen for the analysis of the documents. Block-modelling and multi-dimensional scaling (MDS) was used to determine the network structures. The UCINET software was employed to analyse the data. Most the main actors of this network are chosen from the government budget. There is no legal communication and cooperation among some of the actors because of their improper position in the network. Seven blocks have been clustered by CONCOR in terms of the actor's degree of similarity. The social distance among the actors of the seven blocks is very short. Power distribution in the field of financial support to the poor has a fragmented structure; however, it is mainly run by a dominant block consisting of The Supreme Council of Welfare and Social Security, Health Insurance Organization, and the Ministry of Health and Medical Education. The financial support for the poor network involves multiple actors. This variety has created a series of confusions in terms of the type, level, and scope of responsibilities among the actors. The weak presence legislative and regulatory institutions and also non-governmental institutions are the main weak points of this network. Copyright © 2017 Elsevier Ltd. All rights reserved.

Extending the Memory of Microcomputers

NASA Technical Reports Server (NTRS)

Wiker, G. A.

1984-01-01

Memory increased while retaining real-time capabilities. Extra memory capacity added to microprocessor without increasing memory address length and special transfer instructions by dedicating block of space in main memory to hold addresses of locations in extra memory.

Degree program changes and curricular flexibility: Addressing long held beliefs about student progression

NASA Astrophysics Data System (ADS)

Ricco, George Dante

In higher education and in engineering education in particular, changing majors is generally considered a negative event - or at least an event with negative consequences. An emergent field of study within engineering education revolves around understanding the factors and processes driving student changes of major. Of key importance to further the field of change of major research is a grasp of large scale phenomena occurring throughout multiple systems, knowledge of previous attempts at describing such issues, and the adoption of metrics to probe them effectively. The problem posed is exacerbated by the drive in higher education institutions and among state legislatures to understand and reduce time-to-degree and student attrition. With these factors in mind, insights into large-scale processes that affect student progression are essential to evaluating the success or failure of programs. The goals of this work include describing the current educational research on switchers, identifying core concepts and stumbling blocks in my treatment of switchers, and using the Multiple Institutional Database for Investigating Engineering Longitudinal Development (MIDFIELD) to explore how those who change majors perform as a function of large-scale academic pathways within and without the engineering context. To accomplish these goals, it was first necessary to delve into a recent history of the treatment of switchers within the literature and categorize their approach. While three categories of papers exist in the literature concerning change of major, all three may or may not be applicable to a given database of students or even a single institution. Furthermore, while the term has been coined in the literature, no portable metric for discussing large-scale navigational flexibility exists in engineering education. What such a metric would look like will be discussed as well as the delimitations involved. The results and subsequent discussion will include a description of changes of major, how they may or may not have a deleterious effect on one's academic pathway, the special context of changes of major in the pathways of students within first-year engineering programs students labeled as undecided, an exploration of curricular flexibility by the construction of a novel metric, and proposed future work.

A fuzzy linguistic model for the prediction of carpal tunnel syndrome risks in an occupational environment.

PubMed

Bell, P M; Crumpton, L

1997-08-01

This research presents the development and evaluation of a fuzzy linguistic model designated to predict the risk of carpal tunnel syndrome (CTS) in an occupational setting. CTS has become one of the largest problems facing ergonomists and the medical community because it is developing in epidemic proportions within the occupational environment. In addition, practitioners are interested in identifying accurate methods for evaluating the risk of CTS in an occupational setting. It is hypothesized that many factors impact an individual's likelihood of developing CTS and the eventual development of CTS. This disparity in the occurrence of CTS for workers with similar backgrounds and work activities has confused researchers and has been a stumbling block in the development of a model for widespread use in evaluating the development of CTS. Thus this research is an attempt to develop a method that can be used to predict the likelihood of CTS risk in a variety of environments. The intent is that this model will be applied eventually in an occupational setting, thus model development was focused on a method that provided a usable interface and the desired system inputs can also be obtained without the benefit of a medical practitioner. The methodology involves knowledge acquisition to identify and categorize a holistic set of risk factors that include task-related, personal, and organizational categories. The determination of relative factor importance was accomplished using analytic hierarchy processing (AHP) analysis. Finally a mathematical representation of the CTS risk was accomplished by utilizing fuzzy set theory in order to quantify linguistic input parameters. An evaluation of the model including determination of sensitivity and specificity is conducted and the results of the model indicate that the results are fairly accurate and this method has the potential for widespread use. A significant aspect of this research is the comparison of this technique to other methods for assessing presence of CTS. The results of this evaluation technique are compared with more traditional methods for assessing the presence of CTS.

Accomplishing Mars exploration goals by returning a simple "locality" sample

NASA Astrophysics Data System (ADS)

McKay, G.; Draper, D.; Bogard, D.; Agee, C.; Ming, D.; Jones, J.

A major stumbling block to a Mars sample return (MSR) mission is cost. This problem is greatly exacerbated by using elaborate rovers, sophisticated on-board instruments, and complex sample selection techniques to maximize diversity. We argue that many key science goals of the Mars Exploration Program may be accomplished by returning a simple "locality" sample from a well-chosen landing site. Such a sample , collected by a simple scoop, would consist of local regolith containing soil, windblown fines, and lithic fragments (plus Martian atmosphere). Even the simplest sample return mission could revolutionize our understanding of Mars, without the need for expensive rovers or sophisticated on-board instruments. We expect that by the time a MSR mission could be flown, information from the Mars Odyssey, Mars Express, 2003 Mars Exploration Rovers, and 2005 Mars Reconnaissance Orbiter will be sufficient to choose a good landing site. Returned samples of Martian regolith have the potential to answer key questions of fundamental importance to the Mars Exploration Program: The search for life; the role and history of water and other volatiles; interpreting remotely-sensed spectral data; and understanding the planet as a system. A locality sample can further the search for life by identifying trace organics, biogenic elements and their isotopic compositions, evidence for water such as hydrous minerals or cements, the Martian soil oxidant, and trace biomarkers. Learning the nature and timing of atmosphere-soil-rock interactions will improve understanding of the role and history of water. An atmosphere sample will reveal fundamental information about current atmospheric processes. Information about the mineralogy and lithology of sample materials, the extent of impact gardening, and the nature of dust coatings and alteration rinds will provide much-needed ground truth for interpreting remotely-sensed data, including Mars Pathfinder. Basic planetology questions that might be answered include the compositions and ages of the highlands or lowlands, and how wet Mars was, and at what time in its history. By bringing a simple locality sample back for analysis in the world's best labs, using the world's most sophisticated state-of-the-art instruments, we can make break-through progress in addressing fundamental questions about Mars.

Making sense of movement in embodied design for mathematics learning.

PubMed

Abrahamson, Dor; Bakker, Arthur

2016-01-01

Embodiment perspectives from the cognitive sciences offer a rethinking of the role of sensorimotor activity in human learning, knowing, and reasoning. Educational researchers have been evaluating whether and how these perspectives might inform the theory and practice of STEM instruction. Some of these researchers have created technological systems, where students solve sensorimotor interaction problems as cognitive entry into curricular content. However, the field has yet to agree on a conceptually coherent and empirically validated design framework, inspired by embodiment perspectives, for developing these instructional resources. A stumbling block toward such consensus, we propose, is an implicit disagreement among educational researchers on the relation between physical movement and conceptual learning. This hypothesized disagreement could explain the contrasting choices we witness among current designs for learning with respect to instructional methodology for cultivating new physical actions - whereas some researchers use an approach of direct instruction, such as explicit teaching of gestures, others use an indirect approach, where students must discover effective movements to solve a task. Prior to comparing these approaches, it may help first to clarify key constructs. In this theoretical essay we draw on embodiment and systems literature as well as findings from our design research so as to offer the following taxonomy that may facilitate discourse about movement in STEM learning: (1) distal movement is the technologically extended effect of physical movement on the environment; (2) proximal movement is the physical movements themselves; and (3) sensorimotor schemes are the routinized patterns of cognitive activity that become enacted through proximal movement by orienting on so-called attentional anchors. Attentional anchors are goal-oriented phenomenological objects or enactive perceptions ("sensori-") that organize proximal movement to effect distal movement ("-motor"). All three facets of movement must be considered in analyzing embodied learning processes. We demonstrate that indirect movement instruction enables students to develop new sensorimotor schemes including attentional anchors as idiosyncratic solutions to physical interaction problems. These schemes are, by necessity, grounded in students' own agentive relation to the world while also grounding target content such as mathematical notions.

[The application of stem together with visible and infrared light in regenerative medicine (Part 2)].

PubMed

Emel'yanov, A N; Kir'yanova, V V

2015-01-01

The objective of the present study was to review the experimental studies concerned with in vitro and in vivo visible and infrared light irradiation of human and animal stem cells (SC) to assess the possibilities of using its photobiomodulatory effects for the purpose of regenerative medicine (RM). Despite the long history of photochromotherapy there is thus far no reliable theoretical basis for the choice of such irradiation parameters as power density, radiation dose and exposure time. Nor is there a generally accepted opinion on the light application for the purpose of regenerative medicine. Therefore, the clinical application of light irradiation remains a matter of controversy, in the first place due to the difficulty of the rational choice of irradiation parameters. In laboratory research, the theoretical basis for the choice of irradiation parameters remains a stumbling block too. A relationship between the increased radiation power density and the cell differentiation rate was documented. SC exposure to light in the absence of the factors causing their differentiation failed to induce it. On the contrary, it increased the features characteristic of undifferentiated cells. The maximum differentiation rate of the same cells was achieved by using irradiation parameters different from those needed to achieve the maxi- mum proliferation rate. The increase of SC differentiation rate upon a rise in radiation power density was induced by increasing ir- radiation energy density. The increase of power density and the reduction of either energy density or exposure time were needed to enhance the SC responsiveness to irradiation in the form of either proliferation or differentiation. The effectiveness of phototherapy at all stages of SC treatment was documented especially when it was applied to stimulate the reservoirs of bone marrow lying far from the site of the pathogenic process together with simultaneous light irradiation of the affected site and pre-treatment of stem cells prior to their administration. Based on the results of this analysis we have proposed "a plot showing the dependence of cell response on the generalized photostimulus" and coined two new terms "photostress" and "photoshock".

Shillapoo Wildlife Area, Annual Report 2007-2008.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calkins, Brian

This report summarizes accomplishments, challenges and successes on WDFW's Shillapoo Wildlife Area funded under Bonneville Power Administration's (BPA) Wildlife Mitigation Program (BPA project No.2003-012-00) during the Fiscal Year 08 contract period October 1, 2007-September 30, 2008. The information presented here is intended to supplement that contained in BPA's PISCES contract development and reporting system. The organization below is by broad categories of work but references are made to individual work elements in the PISCES Statement of Work as appropriate. Significant progress was realized in almost all major work types. Of particular note was progress made in tree plantings and pasturemore » rehabilitation efforts. This year's tree planting effort included five sites detailed below and in terms of the number of plants was certainly the largest effort on the wildlife area to date in one season. The planting itself took a significant amount of time, which was anticipated. However, installation of mats and tubes took much longer than expected which impacted planned fence projects in particular. Survival of the plantings appears to be good. Improvement to the quality of waterfowl pasture habitats is evident on a number of sites due to replanting and weed control efforts. Continuing long-term weed control efforts will be key in improving this particular type of habitat. A prolonged cold, wet spring and a number of equipment breakdowns presented stumbling blocks that impacted schedules and ultimately progress on planned activities. The unusual spring weather delayed fieldwork on pasture planting projects as well as weed control and slowed the process of maintaining trees and shrubs. This time lag also caused the continued deferral of some of our fencing projects. The large brush hog mower had the driveline break twice and the smaller tractor had an engine failure that caused it to be down for over a month. We have modified our budget plan for next year to include a temporary employee that will work primarily on tree maintenance and fencing projects to make sure that we make progress in these areas and we will be investigating whether a heavier duty driveline can be obtained for the mower.« less

C-MORE Scholars Program: Encouraging Hawaii`s Undergraduates to Explore the Ocean and Earth Sciences

NASA Astrophysics Data System (ADS)

Bruno, B. C.; Gibson, B.

2008-05-01

Hawaii residents make up 60% of the undergraduate student body at the University of Hawaii at Manoa (UHM), but they are not studying ocean and earth science. The UHM School of Ocean and Earth Science and Technology offers four undergraduate majors: Geology (22%), Geology & Geophysics (19%), Meteorology (16%), and Global Environmental Science (23%). The numbers in parentheses show the proportion of Hawaii residents in each major, based on 2006 data obtained from the UHM Institutional Research Office. The numbers of Native Hawaiians and Pacific Islanders (NHPI) are considerably smaller. The primary goal of the C-MORE Scholars Program, which will launch in Summer 2008, is to recruit and retain local Hawaii students (esp. NHPI) into earth and ocean science majors. To achieve this goal, the C-MORE Scholars Program will: 1. Actively recruit local students, partly by introducing them and their families to job opportunities in their community. Recruiting will be done in partnership with organizations that have successful track records in working with NHPI students; 2. Retain existing students through proactive counseling and course tutoring. Math and physics courses are stumbling blocks for many ocean and earth science majors, often delaying or even preventing graduation. By offering individual and group tutoring, we hope to help local students succeed in these courses; 3. Provide closely mentored, paid undergraduate research experiences at three different academic levels (trainee, intern, and fellow). This research is the cornerstone of the C-MORE Scholars Program. As students progress through the levels, they conduct higher level research with less supervision. Fellows (the highest level) may serve as peer advisors and tutors to underclassmen and assist with recruitment-related activities; and 4. Create a sense of community among the cohort of C-MORE scholars. A two-day summer residential experience will be instrumental in developing a strong cohort, emphasizing links between Hawaiian culture and science, and establishing pathways towards a science career. During the academic year, cohort-building activities will be scheduled each month or so, and will include career-oriented activities.

Dynamics of living matter: can we ``see'' collective motions in proteins?

NASA Astrophysics Data System (ADS)

Hekstra, Doeke

2015-03-01

Proteins are ideal model systems for quantitative study of the interplay of physical and evolutionary forces. Collective, anharmonic motions of amino acid residues within proteins are thought to be central to their function, and to explain, in large part, the complex dependence of protein function on its constituent parts. Currently, the experimental characterization of such motions poses a major stumbling block on the way to a physical understanding of protein function and evolution. We are addressing this problem in two ways. First, alternate conformations of protein residues can often be distinguished in the electron density estimated from room-temperature X-ray crystallography. The dense packing of residues in the folded protein requires that such conformational variations must propagate through networks of amino acids to preclude local steric clashes. Fraser and colleagues showed that such steric conflicts can be used to extract contact networks of residues collectively switching conformation. We ask if these networks are conserved over homologous sequences and connected to the functional reaction coordinate, both of which would demonstrate their fundamental importance. I will describe initial results for the family of PDZ domains: small ligand-binding proteins for which a network of energetically and conformationally coupled residues controlling ligand affinity has been demonstrated previously by a range of methods. Second, the analysis of collective motions in proteins, by nearly any means, is indirect: nothing is seen moving. To directly induce and ``see'' motions on a range of time scales, we developed a new approach based on (a) electric field pulses to induce motions within a protein crystal and (b) time-resolved crystallography to observe these motions. Since proteins generically have a heterogeneous, modifiable charge distribution, this method could provide a powerful, general way of probing the collective motions, and excited states, of proteins in kinetic and atomic detail. I will present initial experiments showing the method is feasible. Taken together, these experiments begin to provide a basis for the development of a physical theory of proteins consistent with their function and adaptation - the source of their survival throughout the evolutionary process.

Solid electroytes for CNT-based actuators

NASA Astrophysics Data System (ADS)

Riemenschneider, Johannes; Geier, Sebastian; Mahrholz, Thorsten; Mosch, Jürgen; Monner, Hans Peter; Sinapius, Michael

2009-03-01

Actuators based on carbon nanotubes (CNT) have the potential to generate high forces at very low voltages. The density of the raw material is just 1330 kg/m3, which makes them well applicable for lightweight applications. Moreover, active strains of up to 1% can be achieved - due to the CNTs dimensional changes on charge injection. Therefore the nanotubes have to be arranged and electrically wired like electrodes of a capacitor. In previous works the system's response of the Nanotubes comprising a liquid electrolyte was studied in detail. The major challenge is to repeat such experiments with solid electrolytes, which is a prerequisite for structural integration. In this paper a method is proposed which makes sure the expansion is not based on thermal expansion. This is done by analysing the electrical system response. As thermal expansion is dominated by ohmic resistance the CNT based actuators show a strong capacitive behavior. This behavior is referable to the constitution of the electrochemical double layer around the nanotubes, which causes the tubes to expand. Also a novel test setup is described, which guarantees that the displacement which is measured will not be caused by bending of a bimorph but due to expansion of a single layer of nanotubes. This paper also presents experimental results demonstrating both, the method of electrical characterization of CNT based actuators with implemented solid electrolytes and the novel test setup which is used to measure the needed data. The actuators which were characterized are hybrids of CNT and the solid electrolyte NAFION which is supplying the ions needed to constitute the electrochemical double layer. The manufacturing, processing of these actuators and also some first experimental results are shown. Unfortunately, the results are not as clear as those for liquid electrolytes, which depend on the hybrid character of the analyzed devices. In the liquid electrolyte based case the CNTs are the only source of stiffness, whereas in the solid electrolyte case electrodes and electrolyte contribute to the overall stiffness and damping as well. Since the introduction of solid electrolytes is a major stumbling block in the development of such actuators, this work is of particular importance.

Collective arrangements and social networks: Coping strategies for the poor households in the Great Ruaha Catchment in Tanzania

NASA Astrophysics Data System (ADS)

Kadigi, Reuben M. J.; Mdoe, N. S. Y.; Ashimogo, G. C.

Access to water and land resources underpins the socio-economic fabric of many societies in the Southern Africa region, which is characterized broadly as underdeveloped with widespread food insecurity, exacerbated by persistent droughts, erratic rainfalls and increasing human populations. The availability of land and water resources is increasingly diminishing and becoming a stumbling block to the development of the agrarian societies in the region. The poor households have in turn adopted new livelihood coping mechanisms but little research has been done to assess the effectiveness of these ‘instruments’. Consequently, the concepts of sustainable water resources management and agricultural development have remained elusive and poorly understood by policy makers as well as by water resources planners and managers. Recognizing this, a study was conducted between 2002 and 2005 under the RIPARWIN (Raising Irrigation Productivity and Releasing Water for Intersectoral Needs) project to assess the spatial dynamics of livelihood capital, vulnerability and coping strategies for the poor agrarian households in the Upper Great Ruaha River Catchment (GRRC) in Tanzania. The results of analysis showed an array of livelihood platforms and institutional contexts that act to shape the existing livelihood typologies in the GRRC. In addition, the results showed a gradual increase in household vulnerability from upstream to downstream, particularly in terms of access to physical and natural assets. Vulnerability was found to be directly associated with the number of dependants. The female-headed households were relatively more likely to be vulnerable than the male-headed households (cf. probabilities of 27% and 21%, respectively). The value of collective arrangements and drawing on social networks crosscut all social strata and ranked as the most common livelihood strategy. This suggests that the scope for reducing vulnerability among the poor households in the GRRC critically depends on the existing institutional arrangements and mechanisms. Of paramount importance is perhaps the need to facilitate the establishment and empowerment of water use associations and apex bodies. In the study area, this appears to be promising enough to build ‘strong’ institutional platforms through which water and land resources would be managed sustainably.

Guiding science expeditions: The design of a learning environment for project-based science

NASA Astrophysics Data System (ADS)

Polman, Joseph Louis

Project-based pedagogy has been revived recently as a teaching strategy for promoting students' active engagement in learning science by doing science. Numerous reform efforts have encouraged project-based teaching in high schools, along with a range of supports for its implementation, often including computers and the Internet. History has shown, however, that academic research and new technologies are not enough to effect real change in classrooms. Ultimately, teachers accomplish activity with their students daily in classrooms. Putting the idea of project-based teaching into practice depends on many particulars of teachers' situated work with students. To better understand the complexity of project-based science teaching in schools, I conducted an interpretive case study of one exceptional teacher's work. The teacher devotes all class time after the beginning of the year to open-ended, student-designed Earth Science research projects. Over four years of involvement with the Learning through Collaborative Visualization (CoVis) reform effort, this teacher has developed, implemented, and refined strategies for supporting and guiding students in conducting open-ended inquiry. Through a close examination of the teacher's work supporting student projects, I explore the design issues involved in such an endeavor, including affordances, constraints, and tradeoffs. In particular, I show how time constrains both student and teacher action, how the traditional school culture and grading create stumbling blocks for change, and how conflicting beliefs about teaching and learning undermine the accomplishment of guided inquiry. I also show how Internet tools including Usenet news, email, and the World Wide Web afford students an opportunity to gather and make use of distributed expertise and scientific data resources; how an activity structure, combined with a corresponding structure to the artifact of the final written product, supports student accomplishment of unfamiliar practices; and how the teacher guides students in real time through mutually transformative communication. I synthesize the important design elements into a framework for conducting project-based science, especially in settings where such pedagogy is relatively new. This study will inform teachers and reformers of the practical and complex work of implementing project-based teaching in schools.

Chaotic Mountain Blocks in Pluto’s Sputnik Planitia

NASA Astrophysics Data System (ADS)

Singer, Kelsi N.; Knight, Katherine I.; Stern, S. Alan; Olkin, Catherine; Grundy, William M.; McKinnon, William B.; Moore, Jeffrey M.; Schenk, Paul M.; Spencer, John R.; Weaver, Harold A.; Young, Leslie; Ennico, Kimberly; New Horizons Geology, Geophysics and Imaging Science Theme Team, The New Horizons Surface Composition Science Theme Team

2017-10-01

One of the first high-resolution Pluto images returned by New Horizons displayed a collection of tall, jagged peaks rising out of the large nitrogen ice sheet informally known as Sputnik Planitia (SP). This mountain range was later revealed to be one of several along the western edge of SP. The mountains are several hundred broken-up blocks of Pluto’s primarily water ice lithosphere and some retain surface terrains similar to the nearby intact crust surrounding SP. Water ice with some fractures or porosity is likely >5% less dense than solid N2 ice at Pluto’s temperatures. Thus it is possible the blocks are, or were, floating icebergs or at least partially suspended to the point that some blocks appear to be tilted as if they have faltered (Moore et al., 2016, Science, 351, 1284-1293).We analyze four mountain ranges on the western edge of SP and compare to chaotic terrains on Europa and Mars. The blocks on Pluto have angular planforms but we characterize their size using block surface area converted to an equivalent circular diameter. Topography was used to define block extents. The blocks range in size from 3-30 km in diameter, with a mode of ~8-10 km. Blocks range from 0.2-3.8 km in height, and block height generally increases with block diameter. One or more dark layers can be identified in a few scarp faces, and are at a similar depth to each other and to layers seen in fault and crater walls elsewhere on Pluto. A large N-S trending fault system runs tangential to SP and may be the source of crustal disruption on the western side.On Europa and Mars block sizes vary greatly between different chaos regions, but Conamara Chaos has an average block size of ~5 km in diameter, smaller than that typically seen on Pluto. Also the blocks often transition into fractured terrain still connected to the surround lithosphere at the periphery of the chaos regions. The source regions for the blocks are more obvious on Europa and Mars. Additionally the block heights on Europa and Mars generally do not increase with block size. Thus, the main mechanism of crustal breakup is likely different between these bodies.

Women Break an Engineering Barrier: While Other Engineering Disciplines Stumble, BME Represents a Success Story in Attracting American Women to a Male-Dominated Field.

PubMed

Gutierrez, Claudia; Paulosky, Meaghan; Aguinaldo, Angeline; Gerhart, Jackie

2017-01-01

While the field of engineering as a whole is largely male-dominated, biomedical engineering (BME) is one area poised to overturn this trend. Women in the United States were awarded only 20% of all engineering B.S. degrees in 2015; in BME, however, 40.9% of the degree recipients were women. This stands in stark contrast to the more traditional fields of mechanical and electrical engineering, where women were awarded just 13.2% and 12.5% of B.S. degrees, respectively. This trend toward more female participation in BME continues at both the M.S. and Ph.D. degree levels. In fact, in 2015, BME had the highest percentage of female engineering M.S. degree recipients in the United States of all engineering disciplines, according to the American Society for Engineering Education (Figure 1).

Money or your life? The health-wealth trade-off in pharmaceutical regulation.

PubMed

Maynard, A; Cookson, R

2001-07-01

For decades the development of pharmaceuticals has been regulated by safety, efficacy and quality rules for product registration. In public health care systems, these three 'hurdles' are increasingly being supplemented by a fourth: the mandatory requirement to demonstrate economic efficiency in order to obtain reimbursement. This requirement challenges the wealth creation ethic of industry (money) with the population health ethic of public health and health economics (your life). Despite practical and methodological obstacles to the use of economic evidence in decisions, the logic of this development is evident: in order to maximise improvements in population health, scarce resources must be targeted towards developing and applying technologies that deliver the greatest health gains per unit cost. The impact of this policy change on industry practice and profits will be considerable, and companies that fail to demonstrate the economic efficiency of their products will stumble at the fourth hurdle.

Heike Kamerlingh Onnes and the Road to Superconductivity

NASA Astrophysics Data System (ADS)

van Delft, Dirk

2011-03-01

The discovery of superconductivity on 8 April 1911 came as a big surprise. It was stumbled upon in the Leiden cryogenic laboratory of Heike Kamerlingh Onnes in a moment of serendipity. Three years before, the liquefaction of helium on the other hand had been the culmination of a long battle with nature. It was a meticulously prepared operation, ``big science'' in its first appearance. Until recently, careless notebook entries by Kamerlingh Onnes and his terrible handwriting had hindered a complete view to the road to superconductivity. Even a date of the fascinating discovery was lacking. How did the discovery fit into the Leiden research program? What about the research effort Kamerlingh Onnes had to put in to be sure he had found superconductivity rather than a short-circuit? What about superfluidity? Once the right interpretation of the notebooks is clear, the real story can be told.

Everyone Loves Science

NASA Astrophysics Data System (ADS)

Selen, Mats

2014-03-01

Twenty years ago we started a small outreach program at the University of Illinois called ``The Physics Van,'' designed to show the fun of science to assemblies of kids at local elementary schools. Many hundreds of shows - and many hundreds of thousands of excited kids, teachers, and parents later - the program is a cornerstone of the department's outreach efforts. About fourteen years ago I stumbled into a one-time gig with the local CBS television station, which evolved into a weekly live science segment on their morning news show. Very popular with viewers across central Illinois, these science segments now include a colleague from the Department of Chemistry and cover a wide range of topics. The totally unexpected success of both has led me to ponder why these seemingly hapless efforts should have grown to be both successful and sustainable. The conclusions, I believe, are very good news for us all.

Modeling and investigation of the channeling phenomenon in downdraft stratified gasifers.

PubMed

Allesina, Giulio; Pedrazzi, Simone; Tartarini, Paolo

2013-10-01

Downdraft stratified gasifiers seem to be the reactors which are most influenced by loading conditions. Moreover, the larger the reactor is, the higher the possibility to stumble across a channeling phenomenon. This high sensitivity is due to the limited thickness and superficial placement of the flaming pyrolysis layer coupled with the necessity to keep all the zones parallel for a correct running of this kind of gasifier. This study was aimed at modeling and investigating the channeling phenomenon generated by loading condition variations on a 250-kWe nominal power gasification power plant. The experimental campaign showed great variations in most of the plant outputs. These phenomena were modeled on two modified mathematical models obtained from literature. The results of the models confirmed the capability of this approach to predict the channeling phenomena and its dependency on the loading method. Copyright © 2013 Elsevier Ltd. All rights reserved.

Combined KHFAC + DC nerve block without onset or reduced nerve conductivity after block

NASA Astrophysics Data System (ADS)

Franke, Manfred; Vrabec, Tina; Wainright, Jesse; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

2014-10-01

Objective. Kilohertz frequency alternating current (KHFAC) waveforms have been shown to provide peripheral nerve conductivity block in many acute and chronic animal models. KHFAC nerve block could be used to address multiple disorders caused by neural over-activity, including blocking pain and spasticity. However, one drawback of KHFAC block is a transient activation of nerve fibers during the initiation of the nerve block, called the onset response. The objective of this study is to evaluate the feasibility of using charge balanced direct current (CBDC) waveforms to temporarily block motor nerve conductivity distally to the KHFAC electrodes to mitigate the block onset-response. Approach. A total of eight animals were used in this study. A set of four animals were used to assess feasibility and reproducibility of a combined KHFAC + CBDC block. A following randomized study, conducted on a second set of four animals, compared the onset response resulting from KHFAC alone and combined KHFAC + CBDC waveforms. To quantify the onset, peak forces and the force-time integral were measured during KHFAC block initiation. Nerve conductivity was monitored throughout the study by comparing muscle twitch forces evoked by supra-maximal stimulation proximal and distal to the block electrodes. Each animal of the randomized study received at least 300 s (range: 318-1563 s) of cumulative dc to investigate the impact of combined KHFAC + CBDC on nerve viability. Main results. The peak onset force was reduced significantly from 20.73 N (range: 18.6-26.5 N) with KHFAC alone to 0.45 N (range: 0.2-0.7 N) with the combined CBDC and KHFAC block waveform (p < 0.001). The area under the force curve was reduced from 6.8 Ns (range: 3.5-21.9 Ns) to 0.54 Ns (range: 0.18-0.86 Ns) (p < 0.01). No change in nerve conductivity was observed after application of the combined KHFAC + CBDC block relative to KHFAC waveforms. Significance. The distal application of CBDC can significantly reduce or even completely prevent the KHFAC onset response without a change in nerve conductivity.

Influence of internet exposure on sexual behaviour of young persons in an urban district of Southwest Nigeria.

PubMed

Arulogun, Oyedunni Sola; Ogbu, Ifeyinwa Arinze; Dipeolu, Isaac Oluwafemi

2016-01-01

The proportion of young people exposed to pornographic materials through the internet in Nigeria is increasing. However, the influence of the exposure on their sexual behaviour has not been fully explored. This study therefore explored the effects of internet exposure on the sexual behaviour of young persons in Ibadan North Local Government Area of southwest Nigeria. A survey of 413 young persons was done using a pretested self-administered questionnaire which included questions on internet exposure and its influence on behaviour. Data were analysed using descriptive statistics, Chi-square test and logistic regression. Mean age of males was 21.7 ± 3.4 years while that of females was 20.9 ± 3.2 years. Forty-nine percent of the respondents used the internet for the first time between the ages of 15-19 years. Main source of information about the internet was friends (63.3%) and 99.3% accessed the internet from cybercafé. Seventy-two percent had ever stumbled on pornographic sites. Reactions included glancing through before closing (45.2%), closure of the sites (38.5%), and minimizing page to view later (12.5%). Post-exposure influence on behaviour included engagement in oral sex (48.3%), body tattoo (18.3%), having multiple sexual partners (11.6%) and homosexuality (5.0%). More males (95% CI OR =1.245-6.465) and frequent users (95% CI OR =1.168-3.497) were likely to report a change in sexual behaviour. Internet use was common among the young persons. Interventions aimed at reducing exposure to sexual content on internet targeting young persons especially the males and cybercafé operators are advocated.

Influence of internet exposure on sexual behaviour of young persons in an urban district of Southwest Nigeria

PubMed Central

Arulogun, Oyedunni Sola; Ogbu, Ifeyinwa Arinze; Dipeolu, Isaac Oluwafemi

2016-01-01

Introduction The proportion of young people exposed to pornographic materials through the internet in Nigeria is increasing. However, the influence of the exposure on their sexual behaviour has not been fully explored. This study therefore explored the effects of internet exposure on the sexual behaviour of young persons in Ibadan North Local Government Area of southwest Nigeria. Methods A survey of 413 young persons was done using a pretested self-administered questionnaire which included questions on internet exposure and its influence on behaviour. Data were analysed using descriptive statistics, Chi-square test and logistic regression. Results Mean age of males was 21.7 ± 3.4 years while that of females was 20.9 ± 3.2 years. Forty-nine percent of the respondents used the internet for the first time between the ages of 15-19 years. Main source of information about the internet was friends (63.3%) and 99.3% accessed the internet from cybercafé. Seventy-two percent had ever stumbled on pornographic sites. Reactions included glancing through before closing (45.2%), closure of the sites (38.5%), and minimizing page to view later (12.5%). Post-exposure influence on behaviour included engagement in oral sex (48.3%), body tattoo (18.3%), having multiple sexual partners (11.6%) and homosexuality (5.0%). More males (95% CI OR =1.245-6.465) and frequent users (95% CI OR =1.168-3.497) were likely to report a change in sexual behaviour. Conclusion Internet use was common among the young persons. Interventions aimed at reducing exposure to sexual content on internet targeting young persons especially the males and cybercafé operators are advocated. PMID:28293377

Beyond the Bottom of the Foot: Topographic Organization of the Foot Dorsum in Walking.

PubMed

Klarner, Taryn; Pearcey, Gregory E P; Sun, Yao; Barss, Trevor S; Kaupp, Chelsea; Munro, Bridget; Frank, Nick; Zehr, E Paul

2017-12-01

Sensory feedback from the foot dorsum during walking has only been studied globally by whole nerve stimulation. Stimulating the main nerve innervating the dorsal surface produces a functional stumble corrective response that is phase-dependently modulated. We speculated that effects evoked by activation of discrete skin regions on the foot dorsum would be topographically organized, as with the foot sole. Nonnoxious electrical stimulation was delivered to five discrete locations on the dorsal surface of the foot during treadmill walking. Muscle activity from muscles acting at the ankle, knee, hip, and shoulder were recorded along with ankle, knee, and hip kinematics and kinetic information from forces under the foot. All data were sorted on the basis of stimulus occurrence in 12 step cycle phases, before being averaged together within a phase for subsequent analysis. Results reveal dynamic changes in reflex amplitudes and kinematics that are site specific and phase dependent. Most responses from discrete sites on the foot dorsum were seen in the swing phase suggesting function to conform foot trajectory to maintain stability of the moving limb. In general, responses from lateral stimulation differed from medial stimulation, and effects were largest from stimulation at the distal end of the foot at the metatarsals; that is, in anatomical locations where actual impact with an object in the environment is most likely during swing. Responses to stimulation extend to include muscles at the hip and shoulder. We reveal that afferent feedback from specific cutaneous locations on the foot dorsum influences stance and swing phase corrective responses. This emphasizes the critical importance of feedback from the entire foot surface in locomotor control and has application for rehabilitation after neurological injury and in footwear development.

Strategy as active waiting.

PubMed

Sull, Donald N

2005-09-01

Successful executives who cut their teeth in stable industries or in developed countries often stumble when they face more volatile markets. They falter, in part, because they assume they can gaze deep into the future and develop a long-term strategy that will confer a sustainable competitive advantage. But visibility into the future of volatile markets is sharply limited because so many different variables are in play. Factors such as technological innovation, customers' evolving needs, government policy, and changes in the capital markets interact with one another to create unexpected outcomes. Over the past six years, Donald Sull, an associate professor at London Business School, has led a research project examining some of the world's most volatile markets, from national markets like China and Brazil to industries like enterprise software, telecommunications, and airlines. One of the most striking findings from this research is the importance of taking action during comparative lulls in the storm. Huge business opportunities are relatively rare; they come along only once or twice in a decade. And, for the most part, companies can't manufacture those opportunities; changes in the external environment converge to make them happen. What managers can do is prepare for these golden opportunities by managing smart during the comparative calm of business as usual. During these periods of active waiting, leaders must probe the future and remain alert to anomalies that signal potential threats or opportunities; exercise restraint to preserve their war chests; and maintain discipline to keep the troops battle ready. When a golden opportunity or"sudden death"threat emerges, managers must have the courage to declare the main effort and concentrate resources to seize the moment.

Block cipher based on modular arithmetic and methods of information compression

NASA Astrophysics Data System (ADS)

Krendelev, S.; Zbitnev, N.; Shishlyannikov, D.; Gridin, D.

2017-10-01

The article focuses on the description of a new block cipher. Due to the heightened interest in BigData the described cipher is used to encrypt big volumes of data in cloud storage services. The main advantages of the given cipher are the ease of implementation and the possibility of probabilistic encryption. This means that the text encryption will be different when the key is the same and the data is the same. So, the strength of the encryption is improved. Additionally, the ciphered message size can be hardly predicted.

National Program for Inspection of Non-Federal Dams. Lake Gardner Dam (MA 00152), Merrimack River Basin, Amesbury, Massachusetts. Phase I Inspection Report.

DTIC Science & Technology

1978-09-01

embankmenr approximately 750 ft. long and 25 ft. high and an ungrated granite block spillway about 73. ft. wide and 16 ft. high. A 24-in. reservoir...the Location Map, page viii. B. Dam and Appurtenances. Lake Gardner Dam is approxi- mately 1000 ft. long, consisting mainly of an ungated granite block...is a broad crested granite masonry structure, about 16 ft. high and 72. 6 ft. wide. The nine courses of stone ex- posed on the downstream face of the

Traces of warping subsided tectonic blocks on Miranda, Enceladus, Titan

NASA Astrophysics Data System (ADS)

Kochemasov, G.

2007-08-01

Icy satellites of the outer Solar system have very large range of sizes - from kilometers to thousands of kilometers. Bodies less than 400-500 km across have normally irregular shapes , often presenting simple Plato's polyhedrons woven by standing inertiagravity waves (see an accompanying abstract of Kochemasov). Larger bodies with enhanced gravity normally are rounded off and have globular shapes but far from ideal spheres. This is due to warping action of inertia-gravity waves of various wavelengths origin of which is related to body movements in elliptical keplerian orbits with periodically changing accelerations (alternating accelerations cause periodically changing forces acting upon a body what means oscillations of its spheres in form of standing warping waves). The fundamental wave 1 and its first overtone wave 2 produce ubiquitous tectonic dichotomy - two segmental structure and tectonic sectoring superimposed on this dichotomy. Two kinds of tectonic blocks (segments and sectors) are formed: uplifted (+) and subsided (-). Uplifting means increasing planetary radius of blocks, subsiding - decreasing radius (as a sequence subsiding blocks diminishing their surfaces must be warped, folded, wrinkled; uplifting blocks increasing their surfaces tend to be deeply cracked, fallen apart). To level changing angular momenta of blocks subsided areas are filled with denser material than uplifted ones (one of the best examples is Earth with its oceanic basins filled with dense basalts and uplifted continents built of less dense on average andesitic material). Icy satellites follow the same rule. Their warped surfaces show differing chemistries or structures of constructive materials. Uplifted blocks are normally built with light (by color and density) water ice. Subsided blocks - depressions, "seas', "lakes", coronas - by somewhat denser material differing in color from water ice (very sharply - Iapetus, moderately - Europa, slightly - many saturnian satellites). A very sharp difference between uplifted and subsided blocks presents Miranda having very sharp relief range. Subsided areas (coronas) are strongly folded, uplifted areas strongly degassed what was witnessed by numerous craters of various sizes (not all craters are of impact origin!). Coronas on Miranda present subsided segment and sectors. Typical is a very sharp boundary between risen (+) and fallen (-) blocks. On Enceladus the subsided (squeezed) southern pole area is characterized by "tiger stripes" - traces of contraction, young ice deposits and famous ejections of water vapor and ice. The squeezed area expels 'molten" material from interior - compare with periodically active Hawaiian volcano expelling basalts from constantly under contraction Pacific basin interior. As to the subsided Pacific basin, it is antepodean to uplifted deeply cracked and degassing Africa. On Enceladus to contracted south is opposed expanded north where past degassing is witnessed by numerous craters (not all of them are impacts!). Contraction traces are very impressive on subsided Titan's surfaces - methane filled thinly folded huge areas mainly in near equatorial regions (some scientists think that these folds are eolian dunes but they are parallel, not perpendicular to presumed winds and, besides, winds below ˜60 km in Titan's atmosphere are not detected by "Huygens") [1, 2]. This methane rich area of intensive folding is antepodean to the uplifted and mainly composed of water ice region Xanadu cut by numerous tectonically controlled dry "valleys". So, in spite of many varieties of surface features on icy satellites of the outer Solar system a common main tectonic tendency exists: opposition of subsided contracted and uplifted expanded blocks. References: [1] Kochemasov G.G. (2006)Titan's radar images: crosscutting ripples are dunes or warping surface waves?// Berlin, 22-26 Sept. 2006, EUROPLANET Sci. Conf. 1, EPSC2006-A-00045. [2] Kochemasov G.G. (2006)Planetary plains: subsidence and warping // Ibid., EPSC2006-A-00018.

Using a best-practice perioperative governance structure to implement better block scheduling.

PubMed

Heiser, Randy

2013-01-01

Achieving, developing, and maintaining a well-functioning OR scheduling system requires a well-designed perioperative governance structure. Traditional OR/surgery committees, consisting mainly of surgeons, have tried to provide this function but often have not succeeded. An OR governance model should be led by an OR executive committee that functions as a board of directors for the surgery program and works closely with the surgery department medical director and an OR advisory committee. Ideally, the OR executive committee should develop a block schedule that includes a mix of block, open, and urgent or emergent OR access, because this combination is most effective for improving OR use and adapting to changes in surgical procedure volume. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

EnviroAtlas - Portland, ME - Ecosystem Services by Block Group

EPA Pesticide Factsheets

This EnviroAtlas dataset presents environmental benefits of the urban forest in 146 block groups in Portland, Maine. Carbon attributes, temperature reduction, pollution removal and value, and runoff effects are calculated for each block group using i-Tree models (www.itreetools.org), local weather data, pollution data, EPA provided city boundary and land cover data, and U.S. Census derived block group boundary data. This dataset was produced by the US Forest Service to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Effects of copolymer composition, film thickness, and solvent vapor annealing time on dewetting of ultrathin block copolymer films.

PubMed

Huang, Changchun; Wen, Gangyao; Li, Jingdan; Wu, Tao; Wang, Lina; Xue, Feifei; Li, Hongfei; Shi, Tongfei

2016-09-15

Effects of copolymer composition, film thickness, and solvent vapor annealing time on dewetting of spin-coated polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) films (<20nm thick) were mainly investigated by atomic force microscopy. Surface chemical analysis of the ultrathin films annealed for different times were performed using X-ray photoelectron spectroscopy and contact angle measurement. With the annealing of acetone vapor, dewetting of the films with different thicknesses occur via the spinodal dewetting and the nucleation and growth mechanisms, respectively. The PS-b-PMMA films rupture into droplets which first coalesce into large ones to reduce the surface free energy. Then the large droplets rupture into small ones to increase the contact area between PMMA blocks and acetone molecules resulting from ultimate migration of PMMA blocks to droplet surface, which is a novel dewetting process observed in spin-coated films for the first time. Copyright © 2016 Elsevier Inc. All rights reserved.

Two integrator loop quadrature oscillators: A review.

PubMed

Soliman, Ahmed M

2013-01-01

A review of the two integrator loop oscillator circuits providing two quadrature sinusoidal output voltages is given. All the circuits considered employ the minimum number of capacitors namely two except one circuit which uses three capacitors. The circuits considered are classified to four different classes. The first class includes floating capacitors and floating resistors and the active building blocks realizing these circuits are the Op Amp or the OTRA. The second class employs grounded capacitors and includes floating resistors and the active building blocks realizing these circuits are the DCVC or the unity gain cells or the CFOA. The third class employs grounded capacitors and grounded resistors and the active building blocks realizing these circuits are the CCII. The fourth class employs grounded capacitors and no resistors and the active building blocks realizing these circuits are the TA. Transformation methods showing the generation of different classes from each other is given in details and this is one of the main objectives of this paper.

Responsive linear-dendritic block copolymers.

PubMed

Blasco, Eva; Piñol, Milagros; Oriol, Luis

2014-06-01

The combination of dendritic and linear polymeric structures in the same macromolecule opens up new possibilities for the design of block copolymers and for applications of functional polymers that have self-assembly properties. There are three main strategies for the synthesis of linear-dendritic block copolymers (LDBCs) and, in particular, the emergence of click chemistry has made the coupling of preformed blocks one of the most efficient ways of obtaining libraries of LDBCs. In these materials, the periphery of the dendron can be precisely functionalised to obtain functional LDBCs with self-assembly properties of interest in different technological areas. The incorporation of stimuli-responsive moieties gives rise to smart materials that are generally processed as self-assemblies of amphiphilic LDBCs with a morphology that can be controlled by an external stimulus. Particular emphasis is placed on light-responsive LDBCs. Furthermore, a brief review of the biomedical or materials science applications of LDBCs is presented. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spatial distribution pattern of termite in Endau Rompin Plantation

NASA Astrophysics Data System (ADS)

Jalaludin, Nur-Atiqah; Rahim, Faszly

2015-09-01

We censused 18 field blocks approximately 190 ha with total of 28,604 palms in a grid of 2×4 palms from July 2011 to March 2013. The field blocks comprise of rows of palm trees, harvesting paths, field drains and stacking rows with maximum of 30 palms per row, planted about 9 m apart, alternately in maximum of 80 rows. SADIE analysis generating index of aggregation, Ia, local clustering value, Vi and local gap value, Vj is adopted to estimate spatial pattern. The patterns were then presented in contour map using Surfer 12 software. The patterns produced associated with factors i.e. habitat disturbance, habitat fragmentation and resources affecting nesting and foraging activities. Result shows that field blocks with great habitat disturbance recorded highest dead palms and termites hits. Blocks located far from the main access road recorded less than 2% palms with termite hits. This research may provide ecological data on termite spatial pattern in oil palm ecosystem.

1. Photocopy of photograph. ORIGINAL CANAL COAL POCKETS Source: Delaware ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Photocopy of photograph. ORIGINAL CANAL COAL POCKETS Source: Delaware and Hudson Railroad and Canal, by Wayne County Historical Society. - Honesdale Coal Pockets, Main & Commercial Streets, between 700 & 800 blocks, Honesdale, Wayne County, PA

Enhanced proximity warning system (EPWS) for locomotives

DOT National Transportation Integrated Search

1997-10-01

The primary focus of the Enhanced Proximity Warning System (EPWS) is to provide a cost effective means to improve safety of railroad operations, with the ability to implement on an incremental, building block approach. The main safety objective...

6. Photocopy of etching (from collection of New Hampshire Historical ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Photocopy of etching (from collection of New Hampshire Historical Society, Concord, New Hampshire), post 1870 VIEW SOUTHEAST SHOWING WEST FRONT (ELEVATION) - Merchants' Exchange Block, 94-102 North Main Street, Concord, Merrimack County, NH

7. Historic American Buildings Survey, August, 1966 EXTERIOR STAIR TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Historic American Buildings Survey, August, 1966 EXTERIOR STAIR TO SECOND FLOOR, SHOWING PASSAGE BETWEEN MAIN BLOCK AND REAR ELL. - Andrews-Taylor House, State Route 43, Farm Road 2862 Vicinity, Karnack, Harrison County, TX

6. September 1971 DETAIL VIEW OF CHAIN PADLOCK AND KEY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. September 1971 DETAIL VIEW OF CHAIN PADLOCK AND KEY TO SECURE DOOR TO MAIN CELL BLOCK, NOTE STANDARD MODERN PADLOCK FOR SIZE COMPARISON - Jefferson County Jail & Sheriff's Office, Courthouse Square, Madison, Jefferson County, IN

Research on wire rope stress distribution of WR-CVT

NASA Astrophysics Data System (ADS)

Zhang, Wu; Guo, Wei; Zhang, Chuanwei; Lu, Zhengxiong; Xu, Xiaobin

2017-10-01

A wire rope continuously variable transmissions (WR-CVT) has been introduced in the paper, in view of its less research, this paper mainly studied the stress distribution of 6×7+IWS bending wire rope. The results shown that the wire stress is layered distribution in each section, the stress at the outer strand center wire and outer strand side wire was the greatest, the stress value of the outer strand side wire and metal block circular notch is second. As the transmission ratio decreases, the wire stress decreases, which is related to the pulley working radius increases. Compared with the section A1, the stress value on the section A2 is smaller, mainly because the section A2 is not in contact with the metal block or the contact pressure is small. This study provides a basis for the study of fatigue and wears failure of WR-CVT components.

An engine awaits processing in the new engine shop at KSC

NASA Technical Reports Server (NTRS)

1998-01-01

A new Block 2A engine awaits processing in the low bay of the Space Shuttle Main Engine Processing Facility (SSMEPF). Officially opened on July 6, the new facility replaces the Shuttle Main Engine Shop. The SSMEPF is an addition to the existing Orbiter Processing Facility Bay 3. The engine is scheduled to fly on the Space Shuttle Endeavour during the STS-88 mission in December 1998.

Hot Wax Sweeps Debris From Narrow Passages

NASA Technical Reports Server (NTRS)

Ricklefs, Steven K.

1990-01-01

Safe and effective technique for removal of debris and contaminants from narrow passages involves entrainment of undesired material in thermoplastic casting material. Semisolid wax slightly below melting temperature pushed along passage by pressurized nitrogen to remove debris. Devised to clean out fuel passages in main combustion chamber of Space Shuttle main engine. Also applied to narrow, intricate passages in internal-combustion-engine blocks, carburetors, injection molds, and other complicated parts.

A Description of the Building Materials Data Base for Portland, Maine.

DTIC Science & Technology

1986-06-01

WORDS (Continue on reveree side if neceseary and Identify by block number)". Acid precipitation, , Data bases, Damage assessment, Environmental...protection) Damage from acid deposition, Portland, Maine Damage to buildings, - Statistical analysis, . 20. ASsrRACT (Conlaue a reverse e(A It n -cwery md...types and amounts of building surface materials ex- posed to acid deposition. The stratified, systematic, unaligned random sampling approach was used

Bupivacaine digital blocks: how long is the pain relief and temperature elevation?

PubMed

Calder, Kevin; Chung, Bryan; O'Brien, Cliona; Lalonde, Donald H

2013-05-01

The goals of this study are threefold: (1) to determine what effect epinephrine has on the duration of bupivacaine finger block anesthesia; (2) to see whether the duration of action of bupivacaine on digital pain relief is the same duration as numbness to touch/pressure; and (3) to assess the fingertip temperature changes that result from bupivacaine digital blocks. The ring fingers of both hands of 44 volunteers were randomized to injection of bupivacaine with or without 1:200,000 epinephrine. The durations of time for digits to return to normal pain, touch, pressure sensation, and fingertip temperature were measured and recorded. There were three main findings: (1) the pain block of bupivacaine lasts only half as long (15 hours) as the return to normal sensation (30 hours); (2) the effect of adding epinephrine to bupivacaine prolongs the duration of pain relief in a finger block for only an additional 1.5 hours; (3) in addition to pain relief, bupivacaine finger blocks cause fingertip hyperemia with consistent significant fingertip temperature elevation that lasts 15 hours. The duration of bupivacaine pain relief is the clinically important factor that needs to be reported in bupivacaine trials. Patients should be informed that the return of pain will occur much sooner than the return of normal sensation. Adding epinephrine to bupivacaine does not add a clinically significant length of time to pain relief. Bupivacaine finger blocks provide prolonged hyperemia and pain block to fingertips, which may be useful in the treatment of acute frostbite. Therapeutic, I.

Lumbar plexus block using high-pressure injection leads to contralateral and epidural spread.

PubMed

Gadsden, Jeff C; Lindenmuth, Danielle M; Hadzic, Admir; Xu, Daquan; Somasundarum, Lakshmanasamy; Flisinski, Kamil A

2008-10-01

The main advantage of lumbar plexus block over neuraxial anesthesia is unilateral blockade; however, the relatively common occurrence of bilateral spread (up to 27%) makes this advantage unpredictable. The authors hypothesized that high injection pressures during lumbar plexus block carry a higher risk of bilateral or neuraxial anesthesia. Eighty patients undergoing knee arthroscopy (age 18-65 yr; American Society of Anesthesiologists physical status I or II) during a standard, nerve stimulator-guided lumbar plexus block using 35 ml mepivacaine, 1.5%, were scheduled to be studied. Patients were randomly assigned to receive either a low-pressure (< 15 psi) or a high-pressure (> 20 psi) injection, as assessed by an inline injection pressure monitor (BSmart; Concert Medical LLC, Norwell, MA). The block success rate and the presence of bilateral sensory and/or motor blockade were assessed. An interim analysis was performed at n = 20 after an unexpectedly high number of patients had neuraxial spread, necessitating early termination of the study. Five of 10 patients (50%) in the high-pressure group had a neuraxial block with a dermatomal sensory level T10 or higher. In contrast, no patient in the low-pressure group (n = 10) had evidence of neuraxial spread. Moreover, 6 patients (60%) in the high-pressure group demonstrated bilateral sensory blockade in the femoral distribution, whereas no patient in the low-pressure group had evidence of a bilateral femoral block. Injection of local anesthetic with high injection pressure (> 20 psi) during lumbar plexus block commonly results in unwanted bilateral blockade and is associated with high risk of neuraxial blockade.

Electrophysiological evidence of doubly innervated branched muscle fibers in the human brachioradialis muscle.

PubMed

Lateva, Zoia C; McGill, Kevin C

2007-12-01

Motor-unit action potentials (MUAPs) with unstable satellite (late-latency) components are found in EMG signals from the brachioradialis muscles of normal subjects. We analyzed the morphology and blocking behavior of these MUAPs to determine their anatomical origin. EMG signals were recorded from the brachioradialis muscles of 5 normal subjects during moderate-level isometric contractions. MUAP waveforms, discharge patterns, and blocking were determined using computer-aided EMG decomposition. Twelve MUAPs with unstable satellite potentials were detected, always two together in the same signal. Each MUAP also had a second unstable component associated with its main spike. The blocking behavior of the unstable components depended on how close together the two MUAPs were when they discharged. The latencies and blocking behavior indicate that the unstable components came from branched muscle fibers innervated by two different motoneurons. The satellite potentials were due to action potentials that traveled to the branching point along one branch and back along the other. The blockings were due to action-potential collisions when both motoneurons discharged close together in time. Animal studies suggest that branched muscle fibers may be a normal characteristic of series-fibered muscles. This study adds to our understanding of these muscles in humans.

Some Improvements in Utilization of Flash Memory Devices

NASA Technical Reports Server (NTRS)

Gender, Thomas K.; Chow, James; Ott, William E.

2009-01-01

Two developments improve the utilization of flash memory devices in the face of the following limitations: (1) a flash write element (page) differs in size from a flash erase element (block), (2) a block must be erased before its is rewritten, (3) lifetime of a flash memory is typically limited to about 1,000,000 erases, (4) as many as 2 percent of the blocks of a given device may fail before the expected end of its life, and (5) to ensure reliability of reading and writing, power must not be interrupted during minimum specified reading and writing times. The first development comprises interrelated software components that regulate reading, writing, and erasure operations to minimize migration of data and unevenness in wear; perform erasures during idle times; quickly make erased blocks available for writing; detect and report failed blocks; maintain the overall state of a flash memory to satisfy real-time performance requirements; and detect and initialize a new flash memory device. The second development is a combination of hardware and software that senses the failure of a main power supply and draws power from a capacitive storage circuit designed to hold enough energy to sustain operation until reading or writing is completed.