Automated Student Aid Processing: The Challenge and Opportunity.

Science.gov (United States)

St. John, Edward P.

1985-01-01

To utilize automated technology for student aid processing, it is necessary to work with multi-institutional offices (student aid, admissions, registration, and business) and to develop automated interfaces with external processing systems at state and federal agencies and perhaps at need-analysis organizations and lenders. (MLW)

From genome to antivirals: SARS as a test tube.

Science.gov (United States)

Kliger, Yossef; Levanon, Erez Y; Gerber, Doron

2005-03-01

The severe acute respiratory syndrome (SARS) epidemic brought into the spotlight the need for rapid development of effective anti-viral drugs against newly emerging viruses. Researchers have leveraged the 20-year battle against AIDS into a variety of possible treatments for SARS. Most prominently, based solely on viral genome information, silencers of viral genes, viral-enzyme blockers and viral-entry inhibitors were suggested as potential therapeutic agents for SARS. In particular, inhibitors of viral entry, comprising therapeutic peptides, were based on the recently launched anti-HIV drug enfuvirtide. This could represent one of the most direct routes from genome sequencing to the discovery of antiviral drugs.

A Self-Instructional Course in Student Financial Aid Administration. Module 17--Evaluation of Student Aid Management: Self-Evaluation, Audit, and Program Review. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The 17th module in the 17-module self-instructional course on student financial aid administration discusses the evaluation of student aid management in terms of self-evaluation, audit, and program review. The full course offers a systematic introduction to the management of federal financial aid programs authorized by Title IV of the Higher…

A Self-Instructional Course in Student Financial Aid Administration. Module 2--Federal Student Financial Aid: History & Current Sources. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The second of 17 modules in a self-instructional course on student financial aid administration, this module offers novice financial aid administrators and other institutional personnel a systematic introduction to the management of federal financial aid programs authorized by the Higher Education Act Title IV. It traces the history of federal…

Guia para estudiantes: Ayuda economica, 2002-2003 (The Student Guide: Financial Aid, 2002-2003).

Science.gov (United States)

Department of Education, Washington, DC. Student Financial Assistance.

This Spanish-language publication explains what federal student financial aid is and what types of student aid are available. The introductory section, "Student Aid at a Glance," presents information about what student aid is, who gets it, and how to get it. The second section discusses "Finding out about Student Aid." The next…

First Aid Knowledge of University Students in Poisoning Cases.

Science.gov (United States)

Goktas, Sonay; Yildirim, Gulay; Kose, Selmin; Yildirim, Senay; Ozhan, Fatma; Senturan, Leman

2014-12-01

Poisoning is a crucial public health problem which needs serious approach and response to treatment. In case of poisoning, proper first aid is lifesaving and application should be applied in every condition. This research was conducted in order to evaluate first aid knowledge of university students for poisoning. The research was conducted between the dates of May 2013-June 2013 with the permission gained from the University Rectorship. The cohort of the research contained 4,560 students who received education in Istanbul. The sample of the study included 936 students who accepted to participate in the research and attended the school during the research. The data were collected by using a questionnaire form, which had 21 questions prepared by researchers. Analysis of the data was carried out with a percentage evaluation method and chi square tests in a computer environment. In our study, 92.6% of students (n=867) knew the phone number of the ambulance in case of emergency. In addition, 57.3% of students (n=536) knew the phone number of the poison hotline, and it was seen that they answered correctly the questions regarding the relation between body system and indications of poisoning. It was determined that the students who received education in medical departments answered the questions correctly more than the students who had education in other departments. (p≤0.001, p≤0.01). It was observed that the university students in medical departments had more first aid knowledge on poisoning cases compared to the students in other departments who did not have sufficient information regarding these issues. It is thought that first aid education in all departments of universities, both poisoning and other first aid issues, should be conveyed to all students.

Paying for College: Trends in Student Financial Aid at Independent Colleges and Universities.

Science.gov (United States)

Thrift, Julianne Still; Toppe, Christopher M.

Sources of funds for students at private colleges are assessed, along with major changes in student financial aid during 1979-1984, based on the Student Aid Recipient Data Bank of the National Institute of Independent Colleges and Universities. A random sample of actual student financial aid records was examined in order to show how aid is…

State of Student Aid and Higher Education in Texas, 2016

Science.gov (United States)

Fernandez, Chris; Fletcher, Carla; Klepfer, Kasey

2016-01-01

Texas Guaranteed Student Loan Corporation (TG) provides critical support to schools, students, and borrowers at every stage of the federal student aid process--from providing information on how to pay for a higher education including financial aid options, to facilitating successful loan repayment after graduation. This 2016 issue of "State…

Reimagining Financial Aid to Improve Student Access and Outcomes. Executive Summary

Science.gov (United States)

National Association of Student Financial Aid Administrators (NJ1), 2013

2013-01-01

As the student aid programs rapidly approach reauthorization in 2014, they continue to face severe funding and efficiency problems. With grant assistance from the Bill & Melinda Gates Foundation through their "Reimagining Aid Design and Delivery" (RADD) project, the National Association of Student Financial Aid Administrators (NASFAA) examined…

A Self-Instructional Course in Student Financial Aid Administration. Module 6: General Student Eligibility. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

Module 6 of a 17-module self-instructional course on student financial aid administration (for novice aid administrators and other personnel) presents a systematic introduction to the management of federal financial aid programs authorized by Title IV of the Higher Education Act with an emphasis on general student eligibility. Identifying the…

HIV/AIDS Knowledge, Attitudes and Behaviors Assessment of Chinese Students: A Questionnaire Study

Directory of Open Access Journals (Sweden)

Chaojun Xie

2007-09-01

Full Text Available The objective of this study was to assess students' knowledge, attitudes and practices on HIV and AIDS. A questionnaire was administered to a cross section of 259 Chinese undergraduates. Respondents were asked to provide information about knowledge and attitudes about HIV/AIDS. Study results indicated that the majority of undergraduates had a moderate level of HIV and AIDS knowledge, acceptance and attitudes towards people with HIV and AIDS. Boys had more acceptance and positive attitudes towards people with HIV and AIDS than girls. Students majoring in medicine performed better (more knowledgeable and accepting than non-medical students. Differences between students with various monthly expenditures were found-- 6.2% of students had 3-5 sexual partners which has rarely been found in Chinese students; most students did not know HIV VCT centers and most students did not show their confidence for controlling of HIV and AIDS in China. In conclusion, students’ knowledge about HIV/AIDS was uneven. A peer educational program to talk about self esteem, healthy sexual attitudes, being human-accepting and loving should be developed in the near future.

SAR-EDU - An education initiative for applied Synthetic Aperture Radar remote sensing

Science.gov (United States)

Eckardt, Robert; Richter, Nicole; Auer, Stefan; Eineder, Michael; Roth, Achim; Hajnsek, Irena; Walter, Diana; Braun, Matthias; Motagh, Mahdi; Pathe, Carsten; Pleskachevsky, Andrey; Thiel, Christian; Schmullius, Christiane

2013-04-01

Since the 1970s, radar remote sensing techniques have evolved rapidly and are increasingly employed in all fields of earth sciences. Applications are manifold and still expanding due to the continuous development of new instruments and missions as well as the availability of very high-quality data. The trend worldwide is towards operational employment of the various algorithms and methods that have been developed. However, the utilization of operational services does not keep up yet with the rate of technical developments and the improvements in sensor technology. With the enhancing availability and variety of space borne Synthetic Aperture Radar (SAR) data and a growing number of analysis algorithms the need for a vital user community is increasing. Therefore the German Aerospace Center (DLR) together with the Friedrich-Schiller-University Jena (FSU) and the Technical University Munich (TUM) launched the education initiative SAR-EDU. The aim of the project is to facilitate access to expert knowledge in the scientific field of radar remote sensing. Within this effort a web portal will be created to provide seminar material on SAR basics, methods and applications to support both, lecturers and students. The overall intension of the project SAR-EDU is to provide seminar material for higher education in radar remote sensing covering the topic holistically from the very basics to the most advanced methods and applications that are available. The principles of processing and interpreting SAR data are going to be taught using test data sets and open-source as well as commercial software packages. The material that is provided by SAR-EDU will be accessible at no charge from a DLR web portal. The educational tool will have a modular structure, consisting of separate modules that broach the issue of a particular topic. The aim of the implementation of SAR-EDU as application-oriented radar remote sensing educational tool is to advocate the development and wider use of

Cloaked similarity between HIV-1 and SARS-CoV suggests an anti-SARS strategy

Directory of Open Access Journals (Sweden)

Kliger Yossef

2003-09-01

Full Text Available Abstract Background Severe acute respiratory syndrome (SARS is a febrile respiratory illness. The disease has been etiologically linked to a novel coronavirus that has been named the SARS-associated coronavirus (SARS-CoV, whose genome was recently sequenced. Since it is a member of the Coronaviridae, its spike protein (S2 is believed to play a central role in viral entry by facilitating fusion between the viral and host cell membranes. The protein responsible for viral-induced membrane fusion of HIV-1 (gp41 differs in length, and has no sequence homology with S2. Results Sequence analysis reveals that the two viral proteins share the sequence motifs that construct their active conformation. These include (1 an N-terminal leucine/isoleucine zipper-like sequence, and (2 a C-terminal heptad repeat located upstream of (3 an aromatic residue-rich region juxtaposed to the (4 transmembrane segment. Conclusions This study points to a similar mode of action for the two viral proteins, suggesting that anti-viral strategy that targets the viral-induced membrane fusion step can be adopted from HIV-1 to SARS-CoV. Recently the FDA approved Enfuvirtide, a synthetic peptide corresponding to the C-terminal heptad repeat of HIV-1 gp41, as an anti-AIDS agent. Enfuvirtide and C34, another anti HIV-1 peptide, exert their inhibitory activity by binding to a leucine/isoleucine zipper-like sequence in gp41, thus inhibiting a conformational change of gp41 required for its activation. We suggest that peptides corresponding to the C-terminal heptad repeat of the S2 protein may serve as inhibitors for SARS-CoV entry.

Financial Aid to Students in Europe: A Summary Analysis.

Science.gov (United States)

Vorbeck, Michael

1983-01-01

An outline of policies and trends in 21 European countries concerning student financial aid as a form of support for higher education includes a tuition survey, policy purposes and considerations, forms of direct and indirect aid, tax benefits, financial aid systems, and study abroad. (MSE)

Indigenous Knowledge of HIV/AIDS among High School students in Namibia.

Science.gov (United States)

Chinsembu, Kazhila C; Shimwooshili-Shaimemanya, Cornelia N; Kasanda, Choshi D; Zealand, Donovan

2011-06-09

The use of Indigenous Knowledge (IK) can help students to form schemas for interpreting local phenomena through the prism of what they already know. The formation of schemas related to HIV/AIDS risk perception and prevention is important for individuals to form local meanings of the HIV/AIDS epidemic. The objective of this study was to explore the indigenous names and symptoms of HIV/AIDS among High School students in Namibia Focus group discussions were used to collect qualitative data on indigenous names and symptoms of HIV/AIDS from students in 18 secondary schools located in six education regions. Data were grouped into themes. People living with HIV/AIDS were called names meaning prostitute: ihule, butuku bwa sihule, and shikumbu. Names such askibutu bwa masapo (bone disease), katjumba (a young child), kakithi (disease), and shinangele (very thin person) were used to describe AIDS. Derogatory names like mbwa (dog), esingahogo (pretender), ekifi (disease), and shinyakwi noyana (useless person) were also used. Other terms connoted death (zeguru, heaven; omudimba, corpse), fear (simbandembande, fish eagle; katanga kamufifi, (hot ball), and subtle meaning using slang words such as 4 × 4, oondanda ne (four letters), desert soul, and mapilelo (an AIDS service organization). Typical (body wasting) and non-typical (big head, red eyes) symptoms of HIV were also revealed. The study determined students' IK of the names and symptoms of HIV/AIDS. Programmes to prevent/manage adolescent HIV infection and stigma may be strengthened if they take students' indigenous understandings of the disease on board. © 2011 Chinsembu et al; licensee BioMed Central Ltd.

Indigenous knowledge of HIV/AIDS among High School students in Namibia

Directory of Open Access Journals (Sweden)

Zealand Donovan

2011-06-01

Full Text Available Abstract Background The use of Indigenous Knowledge (IK can help students to form schemas for interpreting local phenomena through the prism of what they already know. The formation of schemas related to HIV/AIDS risk perception and prevention is important for individuals to form local meanings of the HIV/AIDS epidemic. The objective of this study was to explore the indigenous names and symptoms of HIV/AIDS among High School students in Namibia Methods Focus group discussions were used to collect qualitative data on indigenous names and symptoms of HIV/AIDS from students in 18 secondary schools located in six education regions. Data were grouped into themes. Results People living with HIV/AIDS were called names meaning prostitute: ihule, butuku bwa sihule, and shikumbu. Names such askibutu bwa masapo (bone disease,katjumba (a young child,kakithi (disease, andshinangele (very thin person were used to describe AIDS. Derogatory names like mbwa (dog, esingahogo (pretender, ekifi (disease, and shinyakwi noyana (useless person were also used. Other terms connoted death (zeguru, heaven; omudimba, corpse, fear (simbandembande, fish eagle; katanga kamufifi, (hot ball, and subtle meaning using slang words such as 4 × 4, oondanda ne (four letters, desert soul, and mapilelo (an AIDS service organization. Typical (body wasting and non-typical (big head, red eyes symptoms of HIV were also revealed. Conclusions The study determined students' IK of the names and symptoms of HIV/AIDS. Programmes to prevent/manage adolescent HIV infection and stigma may be strengthened if they take students' indigenous understandings of the disease on board.

Federal Student Aid Formula: Cost-of-Living Adjustment Could Increase Aid to a Small Percentage of Students in High-Cost Areas but Could Also Further Complicate Aid Process. Report to Congressional Committees. GAO-09-825

Science.gov (United States)

US Government Accountability Office, 2009

2009-01-01

In fiscal year 2008, the Department of Education oversaw the distribution of approximately $96 billion in federal student financial aid, including $14.6 billion in Pell Grants to low- and middle-income students, to help students and their families pay for higher-education expenses. Much of this aid was distributed based on a formula specified in…

State Aid and Student Performance: A Supply-Demand Analysis

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Kinnucan, Henry W.; Zheng, Yuqing; Brehmer, Gerald

2006-01-01

Using a supply-demand framework, a six-equation model is specified to generate hypotheses about the relationship between state aid and student performance. Theory predicts that an increase in state or federal aid provides an incentive to decrease local funding, but that the disincentive associated with increased state aid is moderated when federal…

[Present situation of awareness of acquired immune deficiency syndrome (AIDS) knowledge and AIDS-related behaviors among youth students in gay dating sites].

Science.gov (United States)

2017-06-18

To investigate the awareness of acquired immune deficiency syndrome (AIDS) knowledge and AIDS-related behaviors among youth students in gay dating sites, and to provide evidences for AIDS prevention education through the internet. The students in gay dating sites, selected by a snowball sampling, were interviewed by questionnaires. Chi-square tests were used to analyze the awareness of AIDS knowledge among the students of different characteristics. The Logistic regression was used to analyze the factors associated with ever testing for HIV. In the study, 469 youth students in gay dating sites filled in the questionnaires, and a total of 442 (94.2%) valid samples were collected. The awareness of HIV/AIDS knowledge for the public among the youth students in gay dating sites was 83.9% (371).The awareness of HIV/AIDS knowledge for the youth students was 77.1% (341), and the rate of ever testing for HIV was 52.0% (230). The awareness of HIV/AIDS knowledge for the public in the students were different in different age groups (P=0.001), different marital statuses (Pdating sites was 75.1% (332), and the rate of multiple sexual partnerships among the youth students was 41.3% (137). Compared with homosexual orientation, sexual orientation as heterosexual (OR=0.282, 95%CI: 0.151 to 0.528) and not sure (OR=0.175, 95%CI: 0.035 to 0.885) were risk factors of ever testing for HIV. Multiple sexual partnerships (OR=2.103, 95%CI: 1.278 to 3.462) were promoting factors of ever testing for HIV. The rate of high-risk behaviors among the youth students in gay dating sites was high. The concern should be raised to heterosexual male students who had tendency to homosexual behavior. The AIDS prevention education should be developed in gay dating sites, to improve the self-protection awareness of the youth students.

Teaching advance care planning to medical students with a computer-based decision aid.

Science.gov (United States)

Green, Michael J; Levi, Benjamin H

2011-03-01

Discussing end-of-life decisions with cancer patients is a crucial skill for physicians. This article reports findings from a pilot study evaluating the effectiveness of a computer-based decision aid for teaching medical students about advance care planning. Second-year medical students at a single medical school were randomized to use a standard advance directive or a computer-based decision aid to help patients with advance care planning. Students' knowledge, skills, and satisfaction were measured by self-report; their performance was rated by patients. 121/133 (91%) of students participated. The Decision-Aid Group (n = 60) outperformed the Standard Group (n = 61) in terms of students' knowledge (p satisfaction with their learning experience (p student performance. Use of a computer-based decision aid may be an effective way to teach medical students how to discuss advance care planning with cancer patients.

Student Aid Simplification: Looking Back and Looking Ahead

OpenAIRE

Dynarski, Susan; Wiederspan, Mark

2012-01-01

Each year, 14 million households seeking federal aid for college complete a detailed questionnaire about their finances, the Free Application for Federal Student Aid (FAFSA). With 116 questions, the FAFSA is almost as long as IRS Form 1040 and substantially longer than Forms 1040EZ and 1040A. Aid for college is intended to increase college attendance by reducing its price and loosening liquidity constraints. Economic theory, empirical evidence, and common sense suggest that complexity in appl...

Attitudes of Dental Hygiene Students toward Individuals with AIDS.

Science.gov (United States)

Haring, Joen Iannucci; Lind, Laura J.

1992-01-01

At Ohio State University, 81 dental hygiene students' attitudes toward homosexual and heterosexual patients with acquired immune deficiency syndrome (AIDS) or leukemia were assessed using ratings of prejudice, social interaction, and interpersonal interaction. Negative bias toward individuals with AIDS and unwillingness to engage in everyday…

[Social representation of AIDS among students of Mexico City].

Science.gov (United States)

Flores-Palacios, Fátima; Leyva-Flores, René

2003-01-01

To analyze the social representation of AIDS in a group of high school students aged 16 to 23 years in Mexico City. A non-probabilistic, cross-sectional research was carried out in a public high school in Mexico City. Students of all grades were invited to participate in the study, which took place between 1999 and 2000. Forty-six students participated; 28% male and 72% female. This exploratory field study consisted of three phases, each to address one of three dimensions: cognitive using free association techniques, representational field using semi-structured interviews; and context attitude by means of two discussion groups. In the latter, the information was previously collected for discussion. The cognitive nucleus on AIDS included the association between sex, disease, and death. The representational field of AIDS is constructed around the transmission-prevention unit. Construct elements are virus, contagion, sex, protection, and condom. An ambivalent attitude was identified towards HIV prevention and transmission: "We are only half responsible". Situations such as "rape, blood transfusions, infected syringes" were prominent in the discussion group, deemed beyond their control to prevent transmission, thus explaining the group's ambivalent attitude towards prevention. The usefulness of condoms was associated with prevention of pregnancy rather than with prevention of sexually transmitted infections. The social representation of HIV/AIDS in young students conforms a multidimensional corpus where different elements of scientific order and common sense converge and interact, such as beliefs, myths, taboos, and fears. All of these contribute to construct the meaning of AIDS. The English version of this paper is available at:http://www.insp.mx/salud/index.html.

Ayuda economica: Guia para estudiantes, 2001-2002 (Financial Aid: Student Guide, 2001-2002).

Science.gov (United States)

Office of Student Financial Assistance (ED), Washington, DC.

This guide, written in Spanish, describes federal student aid programs for postsecondary education and how to apply for them. It begins by outlining sources for learning about student aid, such as school financial aid administrators, state higher education agencies, foundations, organizations related to particular fields of interest and toll-free…

An assessment of the knowledge, attitudes, and risk perceptions of pharmacy students regarding HIV/AIDS.

Science.gov (United States)

Ahmed, Syed Imran; Hassali, Mohamed Azmi; Aziz, Noorizan Abdul

2009-02-19

To evaluate the level of knowledge, attitudes, and risk perceptions of University Sains Malaysia final-year pharmacy students regarding human immunodeficiency virus (HIV) and acquired immunity deficiency syndrome (AIDS). A cross-sectional study among pharmacy students. Data were analyzed with Chi-square to find difference at p value AIDS patients. Students recommended HIV testing for health care professionals (69.4%) and patients (75.9%) before surgical procedures. Students knew little about Post Exposure Prophylaxis (18.5%) or about the time for HIV to develop into AIDS (57.4%). About 40% of students were unaware of the inability of antivirals to treat HIV/AIDS. Students had low awareness for opportunistic infections (18.5%), and low agreement on competency to treat and counsel HIV patients (12.9%). The study highlighted students' misconceptions, negative attitudes, and risk perceptions towards HIV/AIDS.

Combined DEM Extration Method from StereoSAR and InSAR

Science.gov (United States)

Zhao, Z.; Zhang, J. X.; Duan, M. Y.; Huang, G. M.; Yang, S. C.

2015-06-01

A pair of SAR images acquired from different positions can be used to generate digital elevation model (DEM). Two techniques exploiting this characteristic have been introduced: stereo SAR and interferometric SAR. They permit to recover the third dimension (topography) and, at the same time, to identify the absolute position (geolocation) of pixels included in the imaged area, thus allowing the generation of DEMs. In this paper, StereoSAR and InSAR combined adjustment model are constructed, and unify DEM extraction from InSAR and StereoSAR into the same coordinate system, and then improve three dimensional positioning accuracy of the target. We assume that there are four images 1, 2, 3 and 4. One pair of SAR images 1,2 meet the required conditions for InSAR technology, while the other pair of SAR images 3,4 can form stereo image pairs. The phase model is based on InSAR rigorous imaging geometric model. The master image 1 and the slave image 2 will be used in InSAR processing, but the slave image 2 is only used in the course of establishment, and the pixels of the slave image 2 are relevant to the corresponding pixels of the master image 1 through image coregistration coefficient, and it calculates the corresponding phase. It doesn't require the slave image in the construction of the phase model. In Range-Doppler (RD) model, the range equation and Doppler equation are a function of target geolocation, while in the phase equation, the phase is also a function of target geolocation. We exploit combined adjustment model to deviation of target geolocation, thus the problem of target solution is changed to solve three unkonwns through seven equations. The model was tested for DEM extraction under spaceborne InSAR and StereoSAR data and compared with InSAR and StereoSAR methods respectively. The results showed that the model delivered a better performance on experimental imagery and can be used for DEM extraction applications.

Turkish and American Undergraduate Students' Attitudes Toward HIV/AIDS Patients: A Comparative Study.

Science.gov (United States)

Atav, A Serdar; Sendir, Merdiye; Darling, Rosa; Acaroglu, Rengin

2015-01-01

Human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) is a complex healthcare problem. Research has demonstrated that negative attitudes affect healthcare provision. The purpose of this study was to compare nursing students' attitudes using the AIDS Attitude Scale (AAS). A descriptive, cross-sectional study was conducted in nursing schools in Istanbul, Turkey, and in Upstate New York (NY). Baccalaureate nursing students (n = 613) from both countries completed the questionnaire. Demographic data, overall AAS attitudes, and attitudes within each subscale were compared. Analyses included frequency and percentages of the grouped variables, arithmetic means and standard deviations, t-test for independent samples, and multiple analysis of variance. Upstate NY students' mean total AAS scores were significantly more positive toward HIV+ patients than Turkish students'. Scores for Professional Resistance and Emotions subscales were significantly more positive for the Upstate NY students, but Fear of Contagion was not. Upstate NY students had more negative attitudes in the contexts of job risk and eating in a restaurant where the chef has AIDS; more professional resistance to referring patients and training specialists for HIV/AIDS patients; and lower tender feelings for people with HIV/AIDS (p < .01 for each). Improvement in students' attitudes is beneficial for promoting nonjudgmental, compassionate care for the HIV+ population. © 2014 Wiley Periodicals, Inc.

HIV/AIDS knowledge among undergraduate university students ...

African Journals Online (AJOL)

EB

Majority of the students reported having received AIDS information from both print and electronic media, but few of them received such information from parents. ... Knowledge and Attitude Inventory 22, 23 were used to gather .... Mother-to-child.

Analyzing Student Aid Packaging To Improve Low-Income and Minority Student Access, Retention and Degree Completion. AIR 1999 Annual Forum Paper.

Science.gov (United States)

Fenske, Robert H.; Porter, John D.; DuBrock, Caryl P.

This study examined the persistence of and financial aid to needy students, underrepresented minority students, and women students, especially those majoring in science, engineering, and mathematics at a large public research university. An institutional student tracking and student financial aid database was used to follow four freshmen cohorts…

Student Financial Aid. High Risk Series.

Science.gov (United States)

General Accounting Office, Washington, DC.

This report discusses the continuing concerns of the U.S. General Accounting Office (GAO) in regard to the Department of Education's management and oversight of postsecondary student financial aid programs, especially the Federal Family Education Loan, the Ford Direct Loan, and the Federal Pell Grant Programs. GAO commends the department for its…

Cracking the Student Aid Code: Parent and Student Perspectives on Paying for College

Science.gov (United States)

College Board Advocacy & Policy Center, 2010

2010-01-01

Paying for college is a challenge for many Americans and navigating the financial aid process can be very difficult, especially for low-income and first-generation college students. The College Board commissioned research to learn more about students' and parents' knowledge, beliefs and attitudes about the importance of a college education and how…

A Self-Instructional Course in Student Financial Aid Administration. Module 15: Internal Aid Office Management and Institutional Quality Control. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The 15th in a 17-module self-instructional course on student financial aid administration (designed for novice financial aid administrators and other institutional personnel) focuses on internal aid office management and institutional quality control. The course provides a systematic introduction to the management of federal financial aid programs…

Investigating the Impact of Financial Aid on Student Dropout Risks: Racial and Ethnic Differences

Science.gov (United States)

Chen, Rong; DesJardins, Stephen L.

2010-01-01

This study focuses on the differences in college student dropout behavior among racial/ethnic groups. We employ event history methods and data from the Beginning Postsecondary Students (BPS) and National Postsecondary Student Aid Study (NPSAS) surveys to investigate how financial aid may differentially influence dropout risks among these student…

Students get wise about AIDS - The acceptability, feasibility and ...

African Journals Online (AJOL)

Objectives. The study assessed the acceptability and feasibility of an AIDS education programme for South African high-school students. Design, setting and sUbjects. A 'before-after' study was conducted in a suburban high school in Cape Town. All 232 standard 8 students were included, and were exposed to the ...

Moral Development, HIV/AIDS Knowledge, and Attitude toward HIV/AIDS among Counseling Students in the United States

Science.gov (United States)

Joe, J. Richelle; Foster, Victoria A.

2017-01-01

People living with HIV/AIDS will likely require services from mental health professionals to address the complex psychosocial effects of the illness. In the United States, counseling students are not likely to be well prepared to serve clients affected by HIV/AIDS, and little is known about their HIV-related knowledge and attitudes. The present…

A Self-Instructional Course in Student Financial Aid Administration. Module 8: Need Analysis. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The eighth module in a 17-module self-instructional program on student financial aid administration (designed for novice student financial aid administrators and other personnel) focuses on need analysis. It provides an introduction to the management of federal financial aid programs authorized by the Higher Education Act Title IV. After…

Renewing and Developing the Partnership: Federal/State/Campus Cooperation in Student Financial Aid.

Science.gov (United States)

Fenske, Robert H., Ed.; Clark, Patricia L., Ed.

The proceedings of the conference are summarized, including a symposium discussion following the formal conference. Contents include: two views of the present advisory structure for student aid (The Case for Maintaining and Expanding the Coalition for the Coordination of Student Financial Aid, by Robert H. Atwell, and The Need for Developing a…

Study Of Knowledge, Attitude And Behaviour Pattern On HIV/AIDS Among Medical Students

Directory of Open Access Journals (Sweden)

Puri K J P S

2003-01-01

Full Text Available A survey of 200 students aged 18 to 23 years attending GGS Medical College and Hospital, Faridkot, assessed their sexual risk practices, AIDS- specific attitudes and beliefs, sexual relationship pattern and preferences and social characteristics. Overall, 39% of students were sexually experienced and these young people had on average, one sexual partner. Only 10% of sexually experienced students said they consistently used condom and 29% said they never did. Unprotected vaginal intercourse was the predominant and preferred sexual practice; it was also the practice that most often occurred with their last sexual partner. In all, 28% of students defined “safer sex” as condom use. Many young people believe that AIDS is a threat only to members of particular “risk groups”; relatively few believed that they could get AIDS (17% or said that AIDS information had influenced their sexual behaviour (29% of those who were sexually experienced. Females were more likely than males to prefer having an exclusive partner and males were more likely to prefer having casual partners.

An elective seminar to teach first-year students the social and medical aspects of AIDS.

Science.gov (United States)

Goldman, J D

1987-07-01

First-year students at a midwestern medical school are introduced to a comprehensive approach to the biological, psychological, and social aspects of acquired immune deficiency syndrome (AIDS). In a seven-week elective seminar (approximately 12 hours in length), the students view a television movie and a documentary film about persons with AIDS and their families and friends, and they participate in roundtable discussions with AIDS patients, volunteers who coordinate support and advocacy for persons with AIDS, and health care professionals involved in the care of AIDS patients. They receive reading materials and lectures on the pathology, epidemiology, and history of AIDS, and they monitor and discuss radio and television reporting on AIDS. In wrap-up sessions and evaluation questionnaires, the students have reported the seminar to be valuable in helping them overcome their fear of the disease, develop empathy for patients with catastrophic diseases, and understand a comprehensive approach to a complex disease.

The effects of computer-aided design software on engineering students' spatial visualisation skills

Science.gov (United States)

Kösa, Temel; Karakuş, Fatih

2018-03-01

The purpose of this study was to determine the influence of computer-aided design (CAD) software-based instruction on the spatial visualisation skills of freshman engineering students in a computer-aided engineering drawing course. A quasi-experimental design was applied, using the Purdue Spatial Visualization Test-Visualization of Rotations (PSVT:R) for both the pre- and the post-test. The participants were 116 freshman students in the first year of their undergraduate programme in the Department of Mechanical Engineering at a university in Turkey. A total of 72 students comprised the experimental group; they were instructed with CAD-based activities in an engineering drawing course. The control group consisted of 44 students who did not attend this course. The results of the study showed that a CAD-based engineering drawing course had a positive effect on developing engineering students' spatial visualisation skills. Additionally, the results of the study showed that spatial visualisation skills can be a predictor for success in a computer-aided engineering drawing course.

TerraSAR-X InSAR multipass analysis on Venice, Italy)

Science.gov (United States)

Nitti, D. O.; Nutricato, R.; Bovenga, F.; Refice, A.; Chiaradia, M. T.; Guerriero, L.

2009-09-01

The TerraSAR-X (copyright) mission, launched in 2007, carries a new X-band Synthetic Aperture Radar (SAR) sensor optimally suited for SAR interferometry (InSAR), thus allowing very promising application of InSAR techniques for the risk assessment on areas with hydrogeological instability and especially for multi-temporal analysis, such as Persistent Scatterer Interferometry (PSI) techniques, originally developed at Politecnico di Milano. The SPINUA (Stable Point INterferometry over Unurbanised Areas) technique is a PSI processing methodology which has originally been developed with the aim of detection and monitoring of coherent PS targets in non or scarcely-urbanized areas. The main goal of the present work is to describe successful applications of the SPINUA PSI technique in processing X-band data. Venice has been selected as test site since it is in favorable settings for PSI investigations (urban area containing many potential coherent targets such as buildings) and in view of the availability of a long temporal series of TerraSAR-X stripmap acquisitions (27 scenes in all). The Venice Lagoon is affected by land sinking phenomena, whose origins are both natural and man-induced. The subsidence of Venice has been intensively studied for decades by determining land displacements through traditional monitoring techniques (leveling and GPS) and, recently, by processing stacks of ERS/ENVISAT SAR data. The present work is focused on an independent assessment of application of PSI techniques to TerraSAR-X stripmap data for monitoring the stability of the Venice area. Thanks to its orbital repeat cycle of only 11 days, less than a third of ERS/ENVISAT C-band missions, the maximum displacement rate that can be unambiguously detected along the Line-of-Sight (LOS) with TerraSAR-X SAR data through PSI techniques is expected to be about twice the corresponding value of ESA C-band missions, being directly proportional to the sensor wavelength and inversely proportional to the

Knowledge and attitudes about HIV/AIDS of dental students from Kuwait and Sri Lanka.

Science.gov (United States)

Ellepola, Arjuna N B; Sundaram, Devipriya B; Jayathilake, Sumedha; Joseph, Bobby K; Sharma, Prem N

2011-04-01

Several studies regarding knowledge and attitudes of dental students towards HIV/AIDS have been reported from various countries. However, to the best of our knowledge, an international comparison between countries with diverse cultural and educational backgrounds has not been reported in the literature. The aim of this study was to compare the knowledge and attitudes towards HIV/AIDS of dental students of Kuwait University (KU), Kuwait and the University of Peradeniya (UP), Sri Lanka, the only dental schools in the respective countries. A cross-sectional survey was conducted among a total of 258 dental students, representing the clinical years of both universities, using a similar structured questionnaire with sixty questions to examine their knowledge of various aspects of HIV/AIDS and thirteen questions to examine their attitudes towards the disease. The mean knowledge and attitude scores were calculated and compared between students from the two universities using t-test with SPSS 17.0. A total of 215 questionnaires were completed and returned, giving a total response rate of 83.3 percent. The KU students were significantly more knowledgeable (p=0.018) regarding HIV/AIDS than the UP students. However, the UP students demonstrated a more highly significant positive attitude (peducation in these countries.

Students' perceptions of a multimedia computer-aided instruction ...

African Journals Online (AJOL)

Objective. To develop an interactive muttimedia-based computer-aided instruction (CAI) programme, to detennine its educational worth and efficacy in a multicuttural academic environment and to evaluate its usage by students with differing levels of computer literacy. Design. A prospective descriptive study evaluating ...

Evaluation of direct and indirect health education in students' knowlege and attitude about AIDS

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Shojaiyzadeh D

1997-08-01

Full Text Available This inverstigation is a quasi-experimental study comparing the effects of two methods of health education on student's knowledge and attitudes about AIDS. The target population consisted of 218 male undergraduates studying in Payame Noor University in Saghez, Iran. A random sample of 106 students was selected using sample random sampling method. The students were randomly divided into two experimental groups. One group was educated about AIDS using a direct method of health education and indirect method was used for the other group. Using pretest/posttest method of data collection, analysis of the data showed a significant difference between each group's knowledge and attitudes before and after the educational programs. Comparison of the two educational methods showed no significant difference on student's knowledge about AIDS. However, method one (using a direct method of health education was significantly more effective in changing student's attitudes towards AIDS than method 2 (using an indirect method of health education.

Factors that influence utilisation of HIV/AIDS prevention methods among university students residing at a selected university campus.

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Ndabarora, Eléazar; Mchunu, Gugu

2014-01-01

Various studies have reported that university students, who are mostly young people, rarely use existing HIV/AIDS preventive methods. Although studies have shown that young university students have a high degree of knowledge about HIV/AIDS and HIV modes of transmission, they are still not utilising the existing HIV prevention methods and still engage in risky sexual practices favourable to HIV. Some variables, such as awareness of existing HIV/AIDS prevention methods, have been associated with utilisation of such methods. The study aimed to explore factors that influence use of existing HIV/AIDS prevention methods among university students residing in a selected campus, using the Health Belief Model (HBM) as a theoretical framework. A quantitative research approach and an exploratory-descriptive design were used to describe perceived factors that influence utilisation by university students of HIV/AIDS prevention methods. A total of 335 students completed online and manual questionnaires. Study findings showed that the factors which influenced utilisation of HIV/AIDS prevention methods were mainly determined by awareness of the existing university-based HIV/AIDS prevention strategies. Most utilised prevention methods were voluntary counselling and testing services and free condoms. Perceived susceptibility and perceived threat of HIV/AIDS score was also found to correlate with HIV risk index score. Perceived susceptibility and perceived threat of HIV/AIDS showed correlation with self-efficacy on condoms and their utilisation. Most HBM variables were not predictors of utilisation of HIV/AIDS prevention methods among students. Intervention aiming to improve the utilisation of HIV/AIDS prevention methods among students at the selected university should focus on removing identified barriers, promoting HIV/AIDS prevention services and providing appropriate resources to implement such programmes.

Knowledge of HIV/AIDS and Risk Behaviour among Students of ...

African Journals Online (AJOL)

This study examined the knowledge and risk behaviours on HIV/AIDS of students in colleges of Education in Osun State. The study sampled 1600 students (male and female) from two colleges of Education. A descriptive survey was adopted for the study using stratified random sampling techniques. A self- developed ...

The knowledge and attitude about HIV/AIDS among Jordanian dental students: (Clinical versus pre clinical students at the University of Jordan

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Shayyab Mohammad H

2011-06-01

Full Text Available Abstract Background The present study aimed to address the suspected deficiency in the level of understanding of HIV/AIDS among clinical and pre clinical dental students at the University of Jordan. In this cross-sectional study, structured questionnaires were distributed to fifth year dental students (n = 121 and to third year dental students (n = 144 in the academic year 2008/2009. Findings Significantly higher percentage of fifth-year students compared to third-year students felt that the teaching they received on cross-infection precautions and barrier dentistry was adequate (P Significantly higher proportion of third-year students compared to fifth-year (39.2% vs. 26.3% thought that HIV patients should be referred to other centers or support groups for treatment (P = 0.04. Conclusions The level of knowledge of Jordanian dental students about HIV and AIDS was generally acceptable; there were inadequacies, however, in their understanding regarding some aspects of AIDS epidemic which demands that dental school curriculum needs some improvement.

SAR matrices: automated extraction of information-rich SAR tables from large compound data sets.

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Wassermann, Anne Mai; Haebel, Peter; Weskamp, Nils; Bajorath, Jürgen

2012-07-23

We introduce the SAR matrix data structure that is designed to elucidate SAR patterns produced by groups of structurally related active compounds, which are extracted from large data sets. SAR matrices are systematically generated and sorted on the basis of SAR information content. Matrix generation is computationally efficient and enables processing of large compound sets. The matrix format is reminiscent of SAR tables, and SAR patterns revealed by different categories of matrices are easily interpretable. The structural organization underlying matrix formation is more flexible than standard R-group decomposition schemes. Hence, the resulting matrices capture SAR information in a comprehensive manner.

Assessing Knowledge of, and Attitudes to, HIV/AIDS among University Students in the United Arab Emirates.

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Haroun, Dalia; El Saleh, Ola; Wood, Lesley; Mechli, Rola; Al Marzouqi, Nada; Anouti, Samir

2016-01-01

The Middle East and North Africa (MENA) region is among the top two regions in the world with the fastest growing HIV epidemic. In this context, risks and vulnerability are high as the epidemic is on the rise with evidence indicating significantly increasing HIV prevalence, new HIV infections and AIDS-related deaths. The aim of the survey was to assess HIV/AIDS knowledge and attitudes related to HIV/AIDS among a wide group of university students in the United Arab Emirates (UAE). In a cross-sectional survey, a total sample of 2,294 students (406 male; 1,888 female) from four universities in three different Emirates in the UAE were approached to take part in the study. Students self-completed a questionnaire that was designed to measure their knowledge and attitudes to HIV/AIDS. The overall average knowledge score of HIV.AIDS was 61%. Non-Emirati and postgraduates demonstrated higher levels of knowledge compared to Emirati and undergraduate students respectively. No significant differences between males and females; and marital status were found. Eighty-five percent of students expressed negative attitudes towards people living with HIV, with Emirati and single students significantly holding more negative attitudes compared to non-Emiratis and those that are married respectively. The findings provide strong evidence that there is a need to advocate for appropriate National HIV/AIDS awareness raising campaigns in universities to reduce the gaps in knowledge and decrease stigmatizing attitudes towards people living with HIV/AIDS.

Perceptual Influence of Ugandan Biology Students' Understanding of HIV/AIDS

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Mutonyi, Harriet; Nashon, Samson; Nielsen, Wendy S.

2010-08-01

In Uganda, curbing the spread of HIV/AIDS has largely depended on public and private media messages about the disease. Media campaigns based on Uganda’s cultural norms of communication are metaphorical, analogical and simile-like. The topic of HIV/AIDS has been introduced into the Senior Three (Grade 11) biology curriculum in Uganda. To what extent do students’ pre-conceptions of the disease, based on these media messages influence students’ development of conceptual understanding of the disease, its transmission and prevention? Of significant importance is the impact the conceptions students have developed from the indirect media messages on classroom instruction on HIV/AIDS. The study is based in a theoretical framework of conceptual change in science learning. An interpretive case study to determine the impact of Ugandan students’ conceptions or perceptions on classroom instruction about HIV/AIDS, involving 160 students aged 15-17, was conducted in four different Ugandan high schools: girls boarding, boys boarding, mixed boarding, and mixed day. Using questionnaires, focus group discussions, recorded biology lessons and informal interviews, students’ preconceptions of HIV/AIDS and how these impact lessons on HIV/AIDS were discerned. These preconceptions fall into four main categories: religious, political, conspiracy and traditional African worldviews. Results of data analysis suggest that students’ prior knowledge is persistent even after biology instructions. This has implications for current teaching approaches, which are mostly teacher-centred in Ugandan schools. A rethinking of the curriculum with the intent of offering science education programs that promote understanding of the science of HIV/AIDS as opposed to what is happening now—insensitivity to misconceptions about the disease—is needed.

Students Talk about Their HIV/AIDS Education Courses: A Case of Addis Ababa, Ethiopia

Science.gov (United States)

Sambe, Mariam M.

2015-01-01

The objective of this research was to explore how Ethiopian high school students experienced the HIV/AIDS education programs offered in their schools. The project also examined gender differences in the way HIV/AIDS education was perceived and the implications for the instructional design of the programs. A total of 15 high school students (eight…

Knowledge of first aid skills among students of a medical college in mangalore city of South India.

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Joseph, N; Kumar, Gs; Babu, Ypr; Nelliyanil, M; Bhaskaran, U

2014-03-01

The adequate knowledge required for handling an emergency without hospital setting at the site of the accident or emergency may not be sufficient as most medical schools do not have formal first aid training in the teaching curriculum. The aim of this study is to assess the level of knowledge of medical students in providing first aid care. This cross-sectional study was conducted during May 2011 among 152 medical students. Data was collected using a self-administered questionnaire. Based on the scores obtained in each condition requiring first aid, the overall knowledge was graded as good, moderate and poor. Only 11.2% (17/152) of the total student participants had previous exposure to first aid training. Good knowledge about first aid was observed in 13.8% (21/152), moderate knowledge in 68.4% (104/152) and poor knowledge in 17.8% (27/152) participants. Analysis of knowledge about first aid management in select conditions found that 21% (32/152) had poor knowledge regarding first aid management for shock and for gastro esophageal reflux disease and 20.4% (31/152) for epistaxis and foreign body in eyes. All students felt that first aid skills need to be taught from the school level onwards and all of them were willing to enroll in any formal first aid training sessions. The level of knowledge about first aid was not good among majority of the students. The study also identified the key areas in which first aid knowledge was lacking. There is thus a need for formal first aid training to be introduced in the medical curriculum.

Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation.

Science.gov (United States)

Nitti, Davide O; Bovenga, Fabio; Chiaradia, Maria T; Greco, Mario; Pinelli, Gianpaolo

2015-07-28

This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system.

Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation

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Davide O. Nitti

2015-07-01

Full Text Available This study explores the potential of Synthetic Aperture Radar (SAR to aid Unmanned Aerial Vehicle (UAV navigation when Inertial Navigation System (INS measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE UAV class, which permits heavy and wide payloads (as required by SAR and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM. A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system.

SARS - Diagnosis

Indian Academy of Sciences (India)

SARS - Diagnosis. Mainly by exclusion of known causes of atypical pneumonia; * X ray Chest; * PCR on body fluids- primers defined by WHO centres available from website.-ve result does not exclude SARS. * Sequencing of amplicons; * Viral Cultures – demanding; * Antibody tests.

Geodetic integration of Sentinel-1A IW data using PSInSAR in Hungary

Science.gov (United States)

Farkas, Péter; Hevér, Renáta; Grenerczy, Gyula

2015-04-01

ESA's latest Synthetic Aperture Radar (SAR) mission Sentinel-1 is a huge step forward in SAR interferometry. With its default acquisition mode called the Interferometric Wide Swath Mode (IW) areas through all scales can be mapped with an excellent return time of 12 days (while only the Sentinel-1A is in orbit). Its operational data policy is also a novelty, it allows scientific users free and unlimited access to data. It implements a new type of ScanSAR mode called Terrain Observation with Progressive Scan (TOPS) SAR. It has the same resolution as ScanSAR but with better signal-to-noise ratio distribution. The bigger coverage is achieved by rotation of the antenna in the azimuth direction, therefore it requires very precise co-registration because even errors under a pixel accuracy can introduce azimuth phase variations caused by differences in Doppler-centroids. In our work we will summarize the benefits and the drawbacks of the IW mode. We would like to implement the processing chain of GAMMA Remote Sensing of such data for mapping surface motion with special attention to the co-registration step. Not only traditional InSAR but the advanced method of Persistent Scatterer InSAR (PSInSAR) will be performed and presented as well. PS coverage, along with coherence, is expected to be good due to the small perpendicular and temporal baselines. We would also like to integrate these measurements into national geodetic networks using common reference points. We have installed trihedral corner reflectors at some selected sites to aid precise collocation. Thus, we aim to demonstrate that Sentinel-1 can be effectively used for surface movement detection and monitoring and it can also provide valuable information for the improvement of our networks.

A Self-Instructional Course in Student Financial Aid Administration. Module 7: Calculating Cost of Attendance. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The seventh module in a 17-module self-instructional course on student financial aid administration (designed for novice student financial aid administrators and other personnel) teaches how to calculate the cost of attendance. It provides a systematic introduction to the management of federal financial aid programs authorized by the Higher…

A Self-Instructional Course in Student Financial Aid Administration. Module 4: The Roles and Responsibilities of the Financial Aid Office. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The fourth module in a self-instructional course for student financial aid administrator neophytes provides an introduction to the management of federal financial aid programs authorized by the Higher Education Act Title IV with an emphasis on the role of the financial aid office. Areas covered in Module 4 include how to recognize the basic areas…

Bistatic sAR data processing algorithms

CERN Document Server

Qiu, Xiaolan; Hu, Donghui

2013-01-01

Synthetic Aperture Radar (SAR) is critical for remote sensing. It works day and night, in good weather or bad. Bistatic SAR is a new kind of SAR system, where the transmitter and receiver are placed on two separate platforms. Bistatic SAR is one of the most important trends in SAR development, as the technology renders SAR more flexible and safer when used in military environments. Imaging is one of the most difficult and important aspects of bistatic SAR data processing. Although traditional SAR signal processing is fully developed, bistatic SAR has a more complex system structure, so sign

Perceptions of Financial Aid: Black Students at a Predominantly White Institution

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Tichavakunda, Antar A.

2017-01-01

This study provides qualitative context for statistics concerning Black college students and financial aid. Using the financial nexus model as a framework, this research draws upon interviews with 29 Black juniors and seniors at a selective, -private, and predominantly White university. The data suggest that students -generally exhibited high…

Market Research on Law School Student Aid Award Letters and Shopping Sheet Information. NASFAA Consumer Information & Law Student Indebtedness Task Force Report

Science.gov (United States)

National Association of Student Financial Aid Administrators, 2016

2016-01-01

"Market Research on Law School Student Aid Award Letters and Shopping Sheet Information" set out to identify through consumer testing what information on the financial aid award letter and U.S. Department of Education's (ED) Shopping Sheet could be modified to create a document that better assists students applying to, or currently…

76 FR 19757 - The Federal Student Aid Programs Under Title IV of the Higher Education Act of 1965, as Amended

Science.gov (United States)

2011-04-08

... institutional verification program, which ultimately makes the financial aid process easier for students, while... institutions to develop and implement their own comprehensive systems to verify student financial aid... institutions have addressed not only the accuracy of student aid awards and payments, but also the management...

A Self-Instructional Course in Student Financial Aid Administration. Module 13: Verification. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

Module 13 of the 17-module self-instructional course on student financial aid administration (designed for novice financial aid administrators and other institutional personnel) focuses on the verification procedure for checking the accuracy of applicant data used in making financial aid awards. The full course provides an introduction to the…

South African Muslim students' attitudes to people with HIV / AIDS

African Journals Online (AJOL)

Winnie

to people with HIV scale, with students indicating positive attitudes to people with HIV. Higher religiosity was ... Whilst research in the 1990s indicated a gender difference in AIDS-related ..... Unpublished doctoral dissertation. University of.

KNOWLEDGE AND ATTITUDES RELATED TO HIV/AIDS AMONG MEDICAL AND ALLIED HEALTH SCIENCES STUDENTS

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Mohammad Akhtar Hussain

2011-12-01

Full Text Available Background: India estimates third highest number of HIV infections in the world, with about 2.4 million people currently living with HIV/AIDS. Adequately trained and sensitized healthcare professionals can play a vital role in combating this epidemic. Limited studies have explored knowledge and attitudes of medical students relating to HIV/AIDS, particularly in the eastern part of India. Methods: The present cross sectional study explored knowledge and attitudes of first year MBBS, BDS & BPT students of Kalinga Institute of Medical Sciences (KIMS, Bhubaneswar, Odisha on HIV/AIDS using a self-administered questionnaire. Data thus collected were analyzedand relevant statistics were calculated. Knowledge and attitude scores were determined and analysis of variance (ANOVA test was used to examine the equality between the groups. Results: All students scored low on the overall knowledge scale (<10/15. Specifically, knowledgewas low on modes of transmission and treatment. Attitudinal scores in the areas of precautions and need for training on HIV was low for all the three streams.The willingness to treat HIV/AIDS patient was found to be high amongst study participants. Conclusion: There is a need and scope to provide correct and detailed information on HIV/AIDS for new entrants in medical and allied health sciences to help them acquire adequate knowledge and develop appropriate attitudes towards HIV/AIDS.

Keynote presentation : SAR systems

NARCIS (Netherlands)

Halsema, D. van; Otten, M.P.G.; Maas, A.P.M.; Bolt, R.J.; Anitori, L.

2011-01-01

Synthetic Aperture Radar (SAR) systems are becoming increasingly important sensors in as well the military environment as in the civilian market. In this keynote presentation an overview will be given over more than 2 decades of SAR system∼ and SAR application development at TNO in the Netherlands.

AIDS knowledge and sexual activity among Flemish secondary school students: a multilevel analysis of the effects of type of education.

Science.gov (United States)

Van Rossem, Ronan; Berten, Hans; Van Tuyckom, Charlotte

2010-01-21

The behavior of adolescents puts them at an increased risk for HIV and other STIs, and their knowledge about HIV/AIDS is often inadequate. An understanding of how AIDS knowledge and sexual activity co-vary among Flemish secondary school students and of how education type, specifically, affects these students is limited. This study addresses the question of whether the effects of education type on HIV/AIDS knowledge and sexual activity are independent of the socio-demographic characteristics of the students. Data from the Flemish Educational Assessment survey, which collected data from a large representative sample of third- and fifth-grade high school students (N = 11,872), were used. Data were analyzed using multilevel logistic and Poisson regression techniques. There is an indication that type of education affects both an adolescent's sexual activity and his/her AIDS knowledge; these effects prove robust for differences in socio-economic backgrounds. Students in lower status education types are more likely to be sexually active and to have poorer AIDS knowledge. The relationship between AIDS knowledge and sexual activity is, however, more complex. Although students in education types with poorer AIDS knowledge are more sexually active, within each of these groups the sexually active have better AIDS knowledge than the non-sexually active. There is also evidence of active information seeking by sexually active students, which leads to improved AIDS knowledge. These findings are consistent with the literature on the role of the educational system in the reproduction of social inequalities. Students from lower status education types are at increased sexual risk compared to those from higher status types. There is also evidence of active information seeking by sexually active students, which leads to improved AIDS knowledge.

Return on the Federal Investment in Student Financial Aid: An Assessment for the High School Class of 1972.

Science.gov (United States)

St. John, Edward P.; Masten, Charles L.

1990-01-01

It is argued that public investment in student financial aid should be evaluated based on tax revenue returns resulting from the expenditure. A model for estimating tax revenue returns from gains in educational attainment attributable to student aid is developed, and impact of aid on access and persistence is examined. (Author/MSE)

Bistatic SAR: Proof of Concept.

Energy Technology Data Exchange (ETDEWEB)

Yocky, David A.; Doren, Neall E.; Bacon, Terry A.; Wahl, Daniel E.; Eichel, Paul H.; Jakowatz, Charles V,; Delaplain, Gilbert G.; Dubbert, Dale F.; Tise, Bertice L.; White, Kyle R.

2014-10-01

Typical synthetic aperture RADAR (SAR) imaging employs a co-located RADAR transmitter and receiver. Bistatic SAR imaging separates the transmitter and receiver locations. A bistatic SAR configuration allows for the transmitter and receiver(s) to be in a variety of geometric alignments. Sandia National Laboratories (SNL) / New Mexico proposed the deployment of a ground-based RADAR receiver. This RADAR receiver was coupled with the capability of digitizing and recording the signal collected. SNL proposed the possibility of creating an image of targets the illuminating SAR observes. This document describes the developed hardware, software, bistatic SAR configuration, and its deployment to test the concept of a ground-based bistatic SAR. In the proof-of-concept experiments herein, the RADAR transmitter will be a commercial SAR satellite and the RADAR receiver will be deployed at ground level, observing and capturing RADAR ground/targets illuminated by the satellite system.

The Seamless SAR Archive (SSARA) Project and Other SAR Activities at UNAVCO

Science.gov (United States)

Baker, S.; Crosby, C. J.; Meertens, C. M.; Fielding, E. J.; Bryson, G.; Buechler, B.; Nicoll, J.; Baru, C.

2014-12-01

The seamless synthetic aperture radar archive (SSARA) implements a seamless distributed access system for SAR data and derived data products (i.e. interferograms). SSARA provides a unified application programming interface (API) for SAR data search and results at the Alaska Satellite Facility and UNAVCO (WInSAR and EarthScope data archives) through the use of simple web services. A federated query service was developed using the unified APIs, providing users a single search interface for both archives. Interest from the international community has prompted an effort to incorporate ESA's Virtual Archive 4 Geohazard Supersites and Natural Laboratories (GSNL) collections and other archives into the federated query service. SSARA also provides Digital Elevation Model access for topographic correction via a simple web service through OpenTopography and tropospheric correction products through JPL's OSCAR service. Additionally, UNAVCO provides data storage capabilities for WInSAR PIs with approved TerraSAR-X and ALOS-2 proposals which allows easier distribution to US collaborators on associated proposals and facilitates data access through the SSARA web services. Further work is underway to incorporate federated data discovery for GSNL across SAR, GPS, and seismic datasets provided by web services from SSARA, GSAC, and COOPEUS.

[Communication between nursing students and patients with Aids].

Science.gov (United States)

de Lima, Ivana Cristina Vieira; Galvão, Marli Teresinha Gimeniz; Costa, Enia; Freitas, Julyana Gomes; Freitag, Lorita Marlena

2011-04-01

This study was performed with the purpose to analyze the communication between nursing students and patients with AIDS during peripheral venous puncture. Video recordings were made of six pairs (student-patient) while performing the venous puncture procedure in May 2009 at a day-hospital in Fortaleza-Ceará. As a group, four judges evaluated the interactions established between the pairs. The analyses were categorized in: Valuing technique over communication; Mask: a barriers to communication; Private space invasion; Interference of the environment in the communication. It was concluded that different factors increase the difficulty establishing an effective communication, especially the need for students to be trained about the importance of establishing communication during care, so as to promote humanized and individual care, in which sensitivity and empathy overlap fear and insecurity.

AWARENESS AND SOCIAL STIGMA ASSOCIATED WITH HIV/AIDS AND TUBERCULOSIS AMONG STUDENTS: A COMPARATIVE STUDY

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Leyanna Susan

2015-11-01

Full Text Available INTRODUCTION Human immunodeficiency virus (HIV and Tuberculosis (TB are two major public health problems that are often seen as co-infections, but are spread via different routes having different treatment strategies and outcomes with one being curable and the other not. However, both these diseases have stigma in common. OBJECTIVES (i To assess the knowledge and social stigma regarding HIV/AIDS. (ii To assess the knowledge and social stigma regarding TB. (iii To study the association between knowledge & social stigma in HIV/AIDS and TB. (ivTo compare the social stigma associated with HIV/AIDS and TB. METHODOLOGY A cross-sectional study was carried out in an urban Arts & Science college situated in Kochi among students aged between 17-24 years. Those students who were not willing to participate and who have/had TB or HIV/AIDS were excluded from the study. A total of 171 students were included in the study by random sampling and a pretested self-administered questionnaire was used.INTRODUCTION Human immunodeficiency virus (HIV and Tuberculosis (TB are two major public health problems that are often seen as co-infections, but are spread via different routes having different treatment strategies and outcomes with one being curable and the other not. However, both these diseases have stigma in common. OBJECTIVES (i To assess the knowledge and social stigma regarding HIV/AIDS. (ii To assess the knowledge and social stigma regarding TB. (iii To study the association between knowledge & social stigma in HIV/AIDS and TB. (ivTo compare the social stigma associated with HIV/AIDS and TB. METHODOLOGY A cross-sectional study was carried out in an urban Arts & Science college situated in Kochi among students aged between 17-24 years. Those students who were not willing to participate and who have/had TB or HIV/AIDS were excluded from the study. A total of 171 students were included in the study by random sampling and a pretested self

AUTOMATIC INTERPRETATION OF HIGH RESOLUTION SAR IMAGES: FIRST RESULTS OF SAR IMAGE SIMULATION FOR SINGLE BUILDINGS

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J. Tao

2012-09-01

Full Text Available Due to the all-weather data acquisition capabilities, high resolution space borne Synthetic Aperture Radar (SAR plays an important role in remote sensing applications like change detection. However, because of the complex geometric mapping of buildings in urban areas, SAR images are often hard to interpret. SAR simulation techniques ease the visual interpretation of SAR images, while fully automatic interpretation is still a challenge. This paper presents a method for supporting the interpretation of high resolution SAR images with simulated radar images using a LiDAR digital surface model (DSM. Line features are extracted from the simulated and real SAR images and used for matching. A single building model is generated from the DSM and used for building recognition in the SAR image. An application for the concept is presented for the city centre of Munich where the comparison of the simulation to the TerraSAR-X data shows a good similarity. Based on the result of simulation and matching, special features (e.g. like double bounce lines, shadow areas etc. can be automatically indicated in SAR image.

Effectiveness of a first-aid intervention program applied by undergraduate nursing students to preparatory school children.

Science.gov (United States)

Wafik, Wagida; Tork, Hanan

2014-03-01

Childhood injuries constitute a major public health problem worldwide. First aid is an effective life-preservation tool at work, school, home, and in public locations. In this study, the effectiveness of a first-aid program delivered by undergraduate nursing students to preparatory school children was examined. This quasi-experimental study was carried out on 100 school children in governmental preparatory schools in Egypt. The researchers designed a program for first-aid training, and this was implemented by trained nursing students. The evaluation involved immediate post-test and follow-up assessment after two months. The results showed generally low levels of satisfactory knowledge and inadequate situational practice among the school students before the intervention. Statistically-significant improvements were shown at the post- and follow-up tests. Multivariate regression analysis identified the intervention and the type of school as the independent predictors of the change in students' knowledge score, while the intervention and the knowledge score were the predictors of the practice score. The study concluded that a first-aid training program delivered by nursing students to preparatory school children is effective in improving their knowledge and practice. © 2013 Wiley Publishing Asia Pty Ltd.

Severe acute respiratory syndrome (SARS)

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SARS; Respiratory failure - SARS ... Complications may include: Respiratory failure Liver failure Heart failure ... 366. McIntosh K, Perlman S. Coronaviruses, including severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). ...

HIV/AIDS awareness and risk behavior among students in Semey, Kazakhstan: a cross-sectional survey

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Ahlm Clas

2008-12-01

Full Text Available Abstract Background Until recently, young people in Kazakhstan have been only moderately affected by the global HIV epidemic. Today, however, the HIV epidemic in Central Asia is one of the most rapidly increasing epidemics in the world. It is mainly concentrated to vulnerable groups such as intravenous drug users, sex workers, the purchasers of sexual services and the financially marginalized. Young, sexually active people may however be the gateway for the epidemic to the general population, and knowledge about their attitudes and behavior is therefore important in planning preventive measures. Methods To gather information about young students and their attitudes and knowledge about HIV/AIDS, we collected 600 structured questionnaires and made 23 semi-structured interviews among three groups of students. Response rate was 99%. Results Almost 99% of the respondents had heard of HIV/AIDS, and 89% could identify ways to protect oneself against sexually transmitted HIV/AIDS. The main routes of transmission, sexual contact without condom and intravenous drug use, were both identified by 97% of the students. Twenty-five percent of the female students and 75% of the male students had had one or more sexual partners. More than 30% of the young men had purchased sex, and homosexuality was widely stigmatized. Conclusion Risks for the spread of HIV/AIDS among young people in Kazakhstan include prostitution as well as stigmatization of the HIV positive and of homosexuals. Protective factors are good knowledge about risks and protection, and opportunities to talk and gather information about sexuality and HIV/AIDS.

Knowledge, attitude and practices of students about first aid epilepsy seizures management in a Northern Indian City.

Science.gov (United States)

Goel, Sonu; Singh, Navpreet; Lal, Vivek; Singh, Amarjeet

2013-10-01

Knowledge about epilepsy and its management is not satisfactory among school students in developing countries. The present study was planned to ascertain the knowledge, attitude and practices (KAP) of students regarding first-aid management of epilepsy seizures in school setting. A total of 177 students of government schools of Chandigarh, a city of northern India, were taken. They were administered with a pre-tested semi-structured questionnaire (for knowledge and attitude assessment) and an observational checklist after role play (for practice assessment) on first-aid management of epilepsy. A scoring system was devised to quantify the knowledge and practices of students. Seventy-one percent of them had either heard or read about epilepsy. Half of the students believed epilepsy as a hindrance to education. Ayurvedic treatment was preferred by more than half of the students; however, many believed that visit to religious places and exorcism as ways to cure epilepsy. Nearly 74% of students would call a doctor as first-aid measure for seizure in a person with epilepsy. We concluded that the knowledge about various aspects of epilepsy was average among school students in Chandigarh. However, there was no significant difference in knowledge, attitude and practice between students who lived in urban, urban slum and rural areas. It is recommended that first-aid management of seizures in epilepsy should be a part of school curriculum.

Mental health first aid training for Australian medical and nursing students: an evaluation study.

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Bond, Kathy S; Jorm, Anthony F; Kitchener, Betty A; Reavley, Nicola J

2015-01-01

The role and demands of studying nursing and medicine involve specific stressors that may contribute to an increased risk for mental health problems. Stigma is a barrier to help-seeking for mental health problems in nursing and medical students, making these students vulnerable to negative outcomes including higher failure rates and discontinuation of study. Mental Health First Aid (MHFA) is a potential intervention to increase the likelihood that medical and nursing students will support their peers to seek help for mental health problems. This study aimed to evaluate the effectiveness of a tailored MHFA course for nursing and medical students. Nursing and medical students self-selected into either a face-to-face or online tailored MHFA course. Four hundred and thirty-four nursing and medical students completed pre- and post-course surveys measuring mental health first aid intentions, mental health literacy, confidence in providing help, stigmatising attitudes and satisfaction with the course. The results of the study showed that both the online and face-to-face courses improved the quality of first aid intentions towards a person experiencing depression, and increased mental health literacy and confidence in providing help. The training also decreased stigmatizing attitudes and desire for social distance from a person with depression. Both online and face-to-face tailored MHFA courses have the potential to improve outcomes for students with mental health problems, and may benefit the students in their future professional careers.

Family communication about HIV/AIDS and sexual behaviour among senior secondary school students in Accra, Ghana.

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Adu-Mireku, Samuel

2003-04-01

Sexually active adolescents in Ghana are increasingly at risk of HIV and other sexually transmitted infections. As a primary agent of socialization, the family can exert a strong influence on adolescent sexual behaviour. Therefore, to aid in the design and implementation of effective prevention programmes, it is important to understand the role of the family in influencing sexual behaviour among school-going adolescents. To evaluate the relationship between family communications about HIV/AIDS and sexual activity and condom use among school-going adolescents in Accra, Ghana. A sample of 894 students (56.9% girls, 43.1% boys; mean age = 17.4 years, SD = 1.40) at two senior secondary schools in Accra completed a modified version of the Youth Risk Behavior Survey (YRBS) questionnaire, a self-administered instrument developed by the Centers for Disease Control and Prevention. Analytical techniques utilized included logistic regression and chi-square. Twenty-five percent of the participants reported being sexually experienced, and 73.6% had talked about HIV/AIDS with parents or other family members. Of the sexually experienced students, 64.7% initiated first sexual intercourse by age 16; and 55.7% did not use a condom at last sexual intercourse. Bivariate analysis showed significant gender differences in sexual activity, condom use, and family communication about HIV/AIDS. Logistic regression analysis showed that student-family communication about HIV/AIDS was not associated with sexual activity. However, communication about HIV/AIDS between students and parents or other family members increased the odds of using a condom at last sexual intercourse. The findings of this study suggest that prevention programmes that seek to educate Ghanaian school-going adolescents about sexual risk behaviour must strongly encourage communication about HIV/AIDS between students and family members.

A Self-Instructional Course in Student Financial Aid Administration. Module 5: Title IV Institutional and Program Eligibility. Second Edition.

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Washington Consulting Group, Inc., Washington, DC.

The fifth module in a 17-module self-instructional course on student financial aid administration teaches novice student financial aid administrators and other personnel about Title IV institutional and program eligibility. This introduction to management of federal financial aid programs authorized by the Higher Education Act Title IV, discusses…

Knowledge and perceptions of sexually transmitted diseases, HIV/AIDS, and reproductive health among female students in Dhaka, Bangladesh

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Sabrina Zaman Mou

2015-01-01

Full Text Available Background: Young people are most vulnerable to sexually transmitted diseases (STDs and human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS in Bangladesh. Lack of knowledge about reproductive health issues is also common in this group. Aims: This study aimed to assess the knowledge and perceptions of STDs, HIV/AIDS, and reproductive health of young female university students (19-27 years in Dhaka, Bangladesh. Methods: A cross-sectional study was carried out among 402 female students from seven universities in Dhaka, Bangladesh. Data were collected through face-to-face interviews using a structured questionnaire on sociodemographic information, knowledge, and perceptions of STDs, HIV/AIDS, and reproductive health. Descriptive analysis was used, and data were presented as frequencies and percentages. Results: The majority of the participants were young, unmarried, undergraduate students. Most of the participants reported that they knew about STDs (79% and HIV/AIDS (66%. However, knowledge about the modes of transmission and prevention of the diseases was poor. HIV/AIDS was considered by 90% participants as a public health threat to Bangladesh, mostly due to illiteracy (76%, increased mortality (20%, existence of risky sexual behavior (18%, and aggression of Western culture (31%. About 65% of the participants mentioned that AIDS can be prevented by safe sexual practice, 55% mentioned prevention through upholding religious values and moral education, and 59% mentioned that education about AIDS would help prevent transmission. Conclusions: Although a majority of young Bangladeshi female students reported knowing about HIV/AIDS, their knowledge regarding transmission and prevention of the diseases was poor. Strategies for creating reproductive health education targeted at young female students are essential for the prevention of STDs and HIV/AIDS.

A Self-Instructional Course in Student Financial Aid Administration. Module 16: Forms and Publications. Second Edition.

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Washington Consulting Group, Inc., Washington, DC.

Module 16 (in a 17-module self-instructional course on student financial aid administration for novice financial aid administrators and other institutional personnel) discusses forms and publications that should be developed and used by the financial aid office. The full course is an introduction to the management of federal financial aid programs…

SAR Target Recognition via Supervised Discriminative Dictionary Learning and Sparse Representation of the SAR-HOG Feature

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Shengli Song

2016-08-01

Full Text Available Automatic target recognition (ATR in synthetic aperture radar (SAR images plays an important role in both national defense and civil applications. Although many methods have been proposed, SAR ATR is still very challenging due to the complex application environment. Feature extraction and classification are key points in SAR ATR. In this paper, we first design a novel feature, which is a histogram of oriented gradients (HOG-like feature for SAR ATR (called SAR-HOG. Then, we propose a supervised discriminative dictionary learning (SDDL method to learn a discriminative dictionary for SAR ATR and propose a strategy to simplify the optimization problem. Finally, we propose a SAR ATR classifier based on SDDL and sparse representation (called SDDLSR, in which both the reconstruction error and the classification error are considered. Extensive experiments are performed on the MSTAR database under standard operating conditions and extended operating conditions. The experimental results show that SAR-HOG can reliably capture the structures of targets in SAR images, and SDDL can further capture subtle differences among the different classes. By virtue of the SAR-HOG feature and SDDLSR, the proposed method achieves the state-of-the-art performance on MSTAR database. Especially for the extended operating conditions (EOC scenario “Training 17 ∘ —Testing 45 ∘ ”, the proposed method improves remarkably with respect to the previous works.

Assessing the Impact of Testing Aids on Post-Secondary Student Performance: A Meta-Analytic Investigation

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Larwin, Karen H.; Gorman, Jennifer; Larwin, David A.

2013-01-01

Testing aids, including student-prepared testing aids (a.k.a., cheat sheets or crib notes) and open-textbook exams, are common practice in post-secondary assessment. There is a considerable amount of published research that discusses and investigates the impact of these testing aids. However, the findings of this research are contradictory and…

The evaluation of first aid and basic life support training for the first year university students.

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Altintaş, Kerim Hakan; Aslan, Dilek; Yildiz, Ali Naci; Subaşi, Nüket; Elçin, Melih; Odabaşi, Orhan; Bilir, Nazmi; Sayek, Iskender

2005-02-01

In Turkey, the first aiders are few in quantity and yet they are required in many settings, such as earthquakes. It was thought that training first year university students in first aid and basic life support (FA-BLS) techniques would serve to increase the number of first aiders. It was also thought that another problem, the lack of first aid trainers, might be addressed by training medical students to perform this function. A project aimed at training first year university students in FA-BLS was conducted at Hacettepe University. In the first phase, medical student first aid trainers (MeSFAT) were trained in FA-BLS training techniques by academic trainers and in the second phase, first year university students were trained in FA-BLS techniques by these peer trainers under the academic trainers' supervision. The purpose of this study was to assess the participants' evaluation of this project and to propose a new program to increase the number of first aiders in the country. In total, 31 medical students were certified as MeSFATs and 12 of these trained 40 first year university students in FA-BLS. Various questionnaires were applied to the participants to determine their evaluation of the training program. Most of the participants and the authors considered the program to be successful and effective. This method may be used to increase the number of first aid trainers and first aiders in the community.

A novel ship CFAR detection algorithm based on adaptive parameter enhancement and wake-aided detection in SAR images

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Meng, Siqi; Ren, Kan; Lu, Dongming; Gu, Guohua; Chen, Qian; Lu, Guojun

2018-03-01

Synthetic aperture radar (SAR) is an indispensable and useful method for marine monitoring. With the increase of SAR sensors, high resolution images can be acquired and contain more target structure information, such as more spatial details etc. This paper presents a novel adaptive parameter transform (APT) domain constant false alarm rate (CFAR) to highlight targets. The whole method is based on the APT domain value. Firstly, the image is mapped to the new transform domain by the algorithm. Secondly, the false candidate target pixels are screened out by the CFAR detector to highlight the target ships. Thirdly, the ship pixels are replaced by the homogeneous sea pixels. And then, the enhanced image is processed by Niblack algorithm to obtain the wake binary image. Finally, normalized Hough transform (NHT) is used to detect wakes in the binary image, as a verification of the presence of the ships. Experiments on real SAR images validate that the proposed transform does enhance the target structure and improve the contrast of the image. The algorithm has a good performance in the ship and ship wake detection.

Knowledge and affective traits of physiotherapy students to provide care for patients living with AIDS.

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Oyeyemi Y. Adetoyeje

2010-02-01

Full Text Available Purpose: This  study  aimed  to  assess  Nigerian physiotherapy students’ knowledge and their affective traits in caring for patients living with AIDS (PWA.Methods: Nigerian students (N=104 in four training programs were surveyed using a 43-item questionnaire that elicited information on the  students’  demographics  characteristics,  knowledge  levels  on AIDS transmission, universal precaution and pathophysiology, their feeling  of  preparedness,  comfort,  ethical  disposition  for  PWA  and their  willingness  to  evaluate  and  provide  care  to  PWA  in  different clinical scenarios.Results: Overall  the  students  showed  unsatisfactory  know ledge  of universal  precaution  and  AIDS  pathophysiology  and  did  not  feel comfortable or prepared to care for PWA. The students did not also show  satisfactory  ethical  disposition  and  may  be  unwilling  to  care for PWA. The students’ knowledge levels on AIDS transmission and willingness were influenced by religious affiliation while feeling of comfort and ethical disposition were influenced by gender and knowing someone living with AIDS. They were more unwilling to provide whirlpool wound care procedures and chest physiotherapy compared to providing gait training, therapeutic exercise and activities of daily living training for PWA.Conclusion: The study identified the need to improve the curriculum on AIDS and recommends clinical clerkship and a methodical and sequential exposure of students to cases during clinical rotations.

Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

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Manabu Watanabe

2010-01-01

Full Text Available We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR σ∘ under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the σ∘ difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that σ∘ and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

Simultaneous Observation Data of GB-SAR/PiSAR to Detect Flooding in an Urban Area

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Shimada Masanobu

2010-01-01

Full Text Available Abstract We analyzed simultaneous observation data with ground-based synthetic aperture radar (GB-SAR and airborne SAR (PiSAR over a flood test site at which a simple house was constructed in a field. The PiSAR under flood condition was 0.9 to 3.4 dB higher than that under nonflood condition. GB-SAR gives high spatial resolution as we could identify a single scattering component and a double bounce component from the house. GB-SAR showed that the difference between the flooding and nonflooding conditions came from the double bounce scattering. We also confirm that the entropy is a sensitive parameter in the eigenvalue decomposition parameters, if the scattering process is dominated by the double bounce scattering. We conclude that and entropy are a good parameter to be used to detect flooding, not only in agricultural and forest regions, but also in urban areas. We also conclude that GB-SAR is a powerful tool to supplement satellite and airborne observation, which has a relatively low spatial resolution.

Knowledge, attitude and practices of students about first aid epilepsy seizures management in a Northern Indian City

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Sonu Goel

2013-01-01

Full Text Available Background: Knowledge about epilepsy and its management is not satisfactory among school students in developing countries. The present study was planned to ascertain the knowledge, attitude and practices (KAP of students regarding first-aid management of epilepsy seizures in school setting. Materials and Methods: A total of 177 students of government schools of Chandigarh, a city of northern India, were taken. They were administered with a pre-tested semi-structured questionnaire (for knowledge and attitude assessment and an observational checklist after role play (for practice assessment on first-aid management of epilepsy. A scoring system was devised to quantify the knowledge and practices of students. Results: Seventy-one percent of them had either heard or read about epilepsy. Half of the students believed epilepsy as a hindrance to education. Ayurvedic treatment was preferred by more than half of the students; however, many believed that visit to religious places and exorcism as ways to cure epilepsy. Nearly 74% of students would call a doctor as first-aid measure for seizure in a person with epilepsy. Conclusion: We concluded that the knowledge about various aspects of epilepsy was average among school students in Chandigarh. However, there was no significant difference in knowledge, attitude and practice between students who lived in urban, urban slum and rural areas. It is recommended that first-aid management of seizures in epilepsy should be a part of school curriculum.

RESEARCH ON COORDINATE TRANSFORMATION METHOD OF GB-SAR IMAGE SUPPORTED BY 3D LASER SCANNING TECHNOLOGY

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P. Wang

2018-04-01

Full Text Available In the image plane of GB-SAR, identification of deformation distribution is usually carried out by artificial interpretation. This method requires analysts to have adequate experience of radar imaging and target recognition, otherwise it can easily cause false recognition of deformation target or region. Therefore, it is very meaningful to connect two-dimensional (2D plane coordinate system with the common three-dimensional (3D terrain coordinate system. To improve the global accuracy and reliability of the transformation from 2D coordinates of GB-SAR images to local 3D coordinates, and overcome the limitation of traditional similarity transformation parameter estimation method, 3D laser scanning data is used to assist the transformation of GB-SAR image coordinates. A straight line fitting method for calculating horizontal angle was proposed in this paper. After projection into a consistent imaging plane, we can calculate horizontal rotation angle by using the linear characteristics of the structure in radar image and the 3D coordinate system. Aided by external elevation information by 3D laser scanning technology, we completed the matching of point clouds and pixels on the projection plane according to the geometric projection principle of GB-SAR imaging realizing the transformation calculation of GB-SAR image coordinates to local 3D coordinates. Finally, the effectiveness of the method is verified by the GB-SAR deformation monitoring experiment on the high slope of Geheyan dam.

Research on Coordinate Transformation Method of Gb-Sar Image Supported by 3d Laser Scanning Technology

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Wang, P.; Xing, C.

2018-04-01

In the image plane of GB-SAR, identification of deformation distribution is usually carried out by artificial interpretation. This method requires analysts to have adequate experience of radar imaging and target recognition, otherwise it can easily cause false recognition of deformation target or region. Therefore, it is very meaningful to connect two-dimensional (2D) plane coordinate system with the common three-dimensional (3D) terrain coordinate system. To improve the global accuracy and reliability of the transformation from 2D coordinates of GB-SAR images to local 3D coordinates, and overcome the limitation of traditional similarity transformation parameter estimation method, 3D laser scanning data is used to assist the transformation of GB-SAR image coordinates. A straight line fitting method for calculating horizontal angle was proposed in this paper. After projection into a consistent imaging plane, we can calculate horizontal rotation angle by using the linear characteristics of the structure in radar image and the 3D coordinate system. Aided by external elevation information by 3D laser scanning technology, we completed the matching of point clouds and pixels on the projection plane according to the geometric projection principle of GB-SAR imaging realizing the transformation calculation of GB-SAR image coordinates to local 3D coordinates. Finally, the effectiveness of the method is verified by the GB-SAR deformation monitoring experiment on the high slope of Geheyan dam.

SAR: Stroke Authorship Recognition

KAUST Repository

Shaheen, Sara

2015-10-15

Are simple strokes unique to the artist or designer who renders them? If so, can this idea be used to identify authorship or to classify artistic drawings? Also, could training methods be devised to develop particular styles? To answer these questions, we propose the Stroke Authorship Recognition (SAR) approach, a novel method that distinguishes the authorship of 2D digitized drawings. SAR converts a drawing into a histogram of stroke attributes that is discriminative of authorship. We provide extensive classification experiments on a large variety of data sets, which validate SAR\\'s ability to distinguish unique authorship of artists and designers. We also demonstrate the usefulness of SAR in several applications including the detection of fraudulent sketches, the training and monitoring of artists in learning a particular new style and the first quantitative way to measure the quality of automatic sketch synthesis tools. © 2015 The Eurographics Association and John Wiley & Sons Ltd.

Bistatic SAR: Imagery & Image Products.

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Yocky, David A.; Wahl, Daniel E.; Jakowatz, Charles V,

2014-10-01

While typical SAR imaging employs a co-located (monostatic) RADAR transmitter and receiver, bistatic SAR imaging separates the transmitter and receiver locations. The transmitter and receiver geometry determines if the scattered signal is back scatter, forward scatter, or side scatter. The monostatic SAR image is backscatter. Therefore, depending on the transmitter/receiver collection geometry, the captured imagery may be quite different that that sensed at the monostatic SAR. This document presents imagery and image products formed from captured signals during the validation stage of the bistatic SAR research. Image quality and image characteristics are discussed first. Then image products such as two-color multi-view (2CMV) and coherent change detection (CCD) are presented.

Methods and Techniques. Student Involvement in the Production of Teaching Aids.

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Fernau, C.

1984-01-01

Indicates that teaching materials used in industrialized countries are not appropriate and often cannot be adapted for the use in developing countries. Having students help with production of teaching aids increases their motivation for using them. (JOW)

Crop Classification by Polarimetric SAR

DEFF Research Database (Denmark)

Skriver, Henning; Svendsen, Morten Thougaard; Nielsen, Flemming

1999-01-01

Polarimetric SAR-data of agricultural fields have been acquired by the Danish polarimetric L- and C-band SAR (EMISAR) during a number of missions at the Danish agricultural test site Foulum during 1995. The data are used to study the classification potential of polarimetric SAR data using...

Undocumented College Students, Taxation, and Financial Aid: A Technical Note

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Olivas, Michael A.

2009-01-01

A surprising amount of litigation and legislation has erupted over undocumented college students. Victims at the federal level are the DREAM Act and immigration reform. Financial aid raises technical issues for undocumented college applicants and for the citizen children of undocumented parents. Generally, the undocumented are ineligible for…

The Effects of Computer-Aided Design Software on Engineering Students' Spatial Visualisation Skills

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Kösa, Temel; Karakus, Fatih

2018-01-01

The purpose of this study was to determine the influence of computer-aided design (CAD) software-based instruction on the spatial visualisation skills of freshman engineering students in a computer-aided engineering drawing course. A quasi-experimental design was applied, using the Purdue Spatial Visualization Test-Visualization of Rotations…

Polarimetric scattering and SAR information retrieval

CERN Document Server

Jin, Ya-Qiu

2013-01-01

Taking an innovative look at Synthetic Aperture Radar (SAR), this practical reference fully covers new developments in SAR and its various methodologies and enables readers to interpret SAR imagery An essential reference on polarimetric Synthetic Aperture Radar (SAR), this book uses scattering theory and radiative transfer theory as a basis for its treatment of topics. It is organized to include theoretical scattering models and SAR data analysis techniques, and presents cutting-edge research on theoretical modelling of terrain surface. The book includes quantitative app

Design and realization of an active SAR calibrator for TerraSAR-X

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Dummer, Georg; Lenz, Rainer; Lutz, Benjamin; Kühl, Markus; Müller-Glaser, Klaus D.; Wiesbeck, Werner

2005-10-01

TerraSAR-X is a new earth observing satellite which will be launched in spring 2006. It carries a high resolution X-band SAR sensor. For high image data quality, accurate ground calibration targets are necessary. This paper describes a novel system concept for an active and highly integrated, digitally controlled SAR system calibrator. A total of 16 active transponder and receiver systems and 17 receiver only systems will be fabricated for a calibration campaign. The calibration units serve for absolute radiometric calibration of the SAR image data. Additionally, they are equipped with an extra receiver path for two dimensional satellite antenna pattern recognition. The calibrator is controlled by a dedicated digital Electronic Control Unit (ECU). The different voltages needed by the calibrator and the ECU are provided by the third main unit called Power Management Unit (PMU).

Bulls, Goats, and Pedagogy: Engaging Students in Overseas Development Aid

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Miles, William F. S.

2009-01-01

This article illustrates the profound learning that occurs--for students and instructor alike--when a class on third-world development attempts to undertake foreign aid. With undergraduate, graduate, and departmental money, I purchased bulls and carts for farmers, and goats for widows, in two West African villages. Such experiential learning…

Estimating the Effect of Student Aid on College Enrollment: Evidence from a Government Grant Policy Reform

DEFF Research Database (Denmark)

Nielsen, Helena Skyt; Sørensen, Torben; Taber, Christopher

In this paper, we investigate the responsiveness of the demand for college to changes in student aid arising from a Danish reform. We separately identify the effect of aid from that of other observed and unobserved variables such as parental income. We exploit the combination of a kinked aid sche...

Medical students' perceptions about the added educational value of student-run HIV/AIDS educational campaigns in the Dominican Republic.

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Chapman, Helena J; Bottentuit-Rocha, Jessica

2016-01-01

This purpose of this report was to examine the perceptions of medical students about the strengths, limitations, and recommendations for improvement of the first known student-run HIV/AIDS educational campaigns in the Dominican Republic (DR), as they relate to the added value applied to their educational training. A retrospective review was conducted on evaluation reports completed by five medical students who coordinated the implementation of three annual HIV/AIDS educational campaigns in five DR communities, between 2012 and 2014. Thematic analysis was used to identify emerging themes related to perceived strengths, limitations, and recommendations for improvement and develop an acronym related to program strengths as value added to medical education. Students highlighted that program strengths were the use of social media technology to facilitate communication and culture-based creativity to capture the attention of target audiences; and limitations were inadequate financial support and HIV-related cultural stigma, due to lack of disease knowledge and awareness or perceived contrasts between the federal system and faith-based community. Recommendations for program improvement, such as comprehensive event preparation and knowing the target audience, were described as key to maximizing the delivery of health messages. Our results highlighted that medical students gained expertise in the effective use of social media technology, culture-based creativity, and team synergy to disseminate HIV/AIDS health information across five DR communities. Students participated in these extracurricular community health campaigns, strengthening skills in communication, health advocacy, and leadership for their medical training. They served as human resources for health and can pave the way as future clinicians and indispensable health educators in local and national health collaborations.

Retention of first aid and basic life support skills in undergraduate medical students

OpenAIRE

Pim A. de Ruijter; Heleen A. Biersteker; Jan Biert; Harry van Goor; Edward C. Tan

2014-01-01

Background: Undergraduate medical students follow a compulsory first aid (FA) and basic life support (BLS) course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in undergraduate medical students.Methods: One hundred and twenty students were randomly selected from first year (n=349) medical students who successfully followed a compulsory FA and BLS course. From thes...

Low-Income Urban High School Students' Use of the Internet to Access Financial Aid

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Venegas, Kristan M.

2006-01-01

This article focuses on the Web-based resources available to low-income students as they build their perceptions, make their decisions, and engage in financial aid activities. Data are gathered from the results of six focus groups with low-income high school students attending urban high schools. Findings suggest that low-income students do have…

Computer-Aided College Algebra: Learning Components that Students Find Beneficial

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Aichele, Douglas B.; Francisco, Cynthia; Utley, Juliana; Wescoatt, Benjamin

2011-01-01

A mixed-method study was conducted during the Fall 2008 semester to better understand the experiences of students participating in computer-aided instruction of College Algebra using the software MyMathLab. The learning environment included a computer learning system for the majority of the instruction, a support system via focus groups (weekly…

Peptide Mimicrying Between SARS Coronavirus Spike Protein and Human Proteins Reacts with SARS Patient Serum

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K.-Y. Hwa

2008-01-01

Full Text Available Molecular mimicry, defined as similar structures shared by molecules from dissimilar genes or proteins, is a general strategy used by pathogens to infect host cells. Severe acute respiratory syndrome (SARS is a new human respiratory infectious disease caused by SARS coronavirus (SARS-CoV. The spike (S protein of SARS-CoV plays an important role in the virus entry into a cell. In this study, eleven synthetic peptides from the S protein were selected based on its sequence homology with human proteins. Two of the peptides D07 (residues 927–937 and D08 (residues 942–951 were recognized by the sera of SARS patients. Murine hyperimmune sera against these peptides bound to proteins of human lung epithelial cells A549. Another peptide D10 (residues 490–502 stimulated A549 to proliferate and secrete IL-8. The present results suggest that the selected S protein regions, which share sequence homology with human proteins, may play important roles in SARS-CoV infection.

Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

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Diego O Andrey

Full Text Available Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1, encoded by tst(H, and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1, RNAIII, rot, and the alternative stress sigma factor sigB (σB. By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

An Elective Seminar to Teach First-Year Students the Social and Medical Aspects of AIDS.

Science.gov (United States)

Goldman, Jonathon D.

1987-01-01

A seven-week seminar Northwestern University introduces medical students to a comprehensive approach to biological, psychological, and social aspects of AIDS. The course includes: a television movie and documentary film; roundtable discussions with AIDS patients, volunteers, and health care professionals; reading materials and lectures; and…

The effects of supplemental online learning aids on student performance and student engagement in Medical Microbiology

Science.gov (United States)

Murray, Kimberly

The purpose of this study was to determine the effects of online learning aids on student performance and engagement. The thirty-five participants of the current study were students enrolled in two sections of a junior level Medical Microbiology laboratory. The experimental section was required to spend ten minutes each week on an online learning aid. The online program, StudyMate(TM), was used to present text and images in the form of flash cards, multiple choice questions, matching, and crossword puzzles. Both groups completed the Index of Learning Style survey, an initial engagement survey at the start of the course, and a final engagement survey at the end of the course. Statistical analysis showed no significant differences between the groups at the start of the course or after the course was completed for learning style, science grade point average, overall grade point average, initial engagement or final engagement. A moderate correlation was found between microbiology course and laboratory grades and a reflective learning style.

Characterizing and estimating noise in InSAR and InSAR time series with MODIS

Science.gov (United States)

Barnhart, William D.; Lohman, Rowena B.

2013-01-01

InSAR time series analysis is increasingly used to image subcentimeter displacement rates of the ground surface. The precision of InSAR observations is often affected by several noise sources, including spatially correlated noise from the turbulent atmosphere. Under ideal scenarios, InSAR time series techniques can substantially mitigate these effects; however, in practice the temporal distribution of InSAR acquisitions over much of the world exhibit seasonal biases, long temporal gaps, and insufficient acquisitions to confidently obtain the precisions desired for tectonic research. Here, we introduce a technique for constraining the magnitude of errors expected from atmospheric phase delays on the ground displacement rates inferred from an InSAR time series using independent observations of precipitable water vapor from MODIS. We implement a Monte Carlo error estimation technique based on multiple (100+) MODIS-based time series that sample date ranges close to the acquisitions times of the available SAR imagery. This stochastic approach allows evaluation of the significance of signals present in the final time series product, in particular their correlation with topography and seasonality. We find that topographically correlated noise in individual interferograms is not spatially stationary, even over short-spatial scales (<10 km). Overall, MODIS-inferred displacements and velocities exhibit errors of similar magnitude to the variability within an InSAR time series. We examine the MODIS-based confidence bounds in regions with a range of inferred displacement rates, and find we are capable of resolving velocities as low as 1.5 mm/yr with uncertainties increasing to ∼6 mm/yr in regions with higher topographic relief.

HIV/AIDS: What do secondary school students know and think ...

African Journals Online (AJOL)

Only 58.1% knew about the condom as a method of prevention. The students demonstrated a poor attitude to HIV/AIDS positive patients as 78.2% would not employ them while 10.6% want them isolated and 36.8% would avoid them. Mass media ;television ( (32.4% ) , radio ( 23.5%)) and health sources ( 26,1% ) were the ...

Assessing ScanSAR Interferometry for Deformation Studies

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Buckley, S. M.; Gudipati, K.

2007-12-01

There is a trend in civil satellite SAR mission design to implement an imaging strategy that incorporates both stripmap mode and ScanSAR imaging. This represents a compromise between high resolution data collection and a desire for greater spatial coverage and more frequent revisit times. However, mixed mode imaging can greatly reduce the number of stripmap images available for measuring subtle ground deformation. Although ScanSAR-ScanSAR and ScanSAR-stripmap repeat-pass interferometry have been demonstrated, these approaches are infrequently used for single interferogram formation and nonexistent for InSAR time series analysis. For future mission design, e.g., a dedicated US InSAR mission, the effect of various ScanSAR system parameter choices on InSAR time series analysis also remains unexplored. Our objective is to determine the utility of ScanSAR differential interferometry. We will demonstrate the use of ScanSAR interferograms for several previous deformation studies: localized and broad-scale urban land subsidence, tunneling, volcanic surface movements and several examples associated with the seismic cycle. We also investigate the effect of various ScanSAR burst synchronization levels on our ability to detect and make quality measurements of deformation. To avoid the issues associated with Envisat ScanSAR burst alignment and to exploit a decade of InSAR measurements, we simulate ScanSAR data by bursting (throwing away range lines of) ERS-1/2 data. All the burst mode datasets are processed using a Modified SPECAN algorithm. To investigate the effects of burst misalignment, a number of cases with varying degrees of burst overlap are considered. In particular, we look at phase decorrelation as a function of percentage of burst overlap. Coherence clearly reduces as the percentage of overlap decreases and we find a useful threshold of 40-70% burst overlap depending on the study site. In order to get a more generalized understanding for different surface conditions

Knowledge, attitudes and perceptions of nurses and nursing students towards HIV/AIDS

Science.gov (United States)

Vallejos, Irma Conejeros; Sánchez, Helga Emig; Lagunas, Lilian Ferrer; Valdés, Báltica Cabieses; Acosta, Rosina Cianelli

2016-01-01

Objective To describe attitudes, knowledge and perceptions of nurses and nursing students towards the people who live with HIV/AIDS (PLWHA). Methodology Bibliographic study in which six electronic databases were searched using the key words: “attitude”, “knowledge”, “nursing”, perceptions”, “HIV/AIDS”. Publications between 1998 and 2007 were considered. Results 560 articles limited by scientific researches or ministerial reports membership were retrieved. Finally a total of 38 publications were selected, the analysis showed that the level of knowledge of nurses and nursing students about PLWHA is good and the attitudes towards HIV/AIDS have improved over time. Nurses and nursing students have been able to identify both positive and negative aspects in the PLWHA care personally and professionally because there is a more favourable perception. Conclusion There are few studies in Latin America and Chile that study the attitudes and knowledge of the studied population towards PLWHA. According to publications found the knowledge and attitudes have improved because the perception is more favourable. PMID:27499563

Policy Analysis Implications of a Model to Improve the Delivery of Financial Aid to Disadvantaged Students. AIR 1983 Annual Forum Paper.

Science.gov (United States)

Fenske, Robert H.; Porter, John D.

The role of institutional research in policy analysis regarding the operation of a computer model for delivery of financial aid to disadvantaged students is considered. A student financial aid model at Arizona State University is designed to develop a profile of late appliers for aid funds and also those who file inaccurate or incomplete…

Science Theatre: Changing South African Students' Intended Behaviour towards HIV AIDS

Science.gov (United States)

Walker, Graham J.; Stocklmayer, Susan M.; Grant, Will J.

2013-01-01

Science centres and other informal learning environments are increasingly becoming venues in which socioscientific issues are presented, sometimes with the aim of influencing attitudes and behaviour. This study investigated the effects of an HIV AIDS science theatre presentation on the behavioural intentions of 697 South African students, a…

[Knowledge about AIDS prevention among professionals and students in health care].

Science.gov (United States)

de Oliveira, A D; Viegas, C R; Sabka, E; Guerra, M; Baltazar, R

1996-07-01

This work is a exploratory research based on the analysis of the answers to the questionnaires of 52 students and health care professionals knowledge about AIDS sexual prevention, biosecurity, diagnosis tests, patients and workers rights and the modifications of nursing and medical care to this kind of disease.

A survey on the knowledge and attitudes among the students of Al-Azhar University to HIV/AIDS, the Gaza Strip-Palestine

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Basil Jabber Kanoa

2015-12-01

Full Text Available Objective: The study assessed the knowledge and attitudes of students’ at a university in Gaza regarding HIV/AIDS and identified differences in knowledge about HIV, and attitudes by gender, locality, and social and economic status. Methods: This descriptive study targeted 492 students of Al-Azhar University-Gaza. The participants completed self-administered questionnaires that included the following dimensions: socio-demographic, measurements of student's knowledge level and measurement of student's attitudes towards HIV/AIDS. Results: Findings showed moderate level of knowledge regarding HIV/AIDS although there was a very low of perception regarding the acceptance and sharing of HIV/AIDS persons. It means that only one third of the study respondents are willingness to be in close touch with people living with HIV or even communication with them, and less than fifty percent thought that it is their right to be engaged in a public or governmental job, stigma and discriminatory attitudes toward HIV/AIDS persons is high only 48% of the students thought it right to employ people living with HIV (PLHIV and 35.5% refused to work in the same place with PLHIV. Conclusion: This study indicates the need for improving the level of knowledge as well as promoting the students' towards positive attitude.Key words: AIDS, Knowledge, attitude, students, HIV, Gaza

SARS-related perceptions in Hong Kong.

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Lau, Joseph T F; Yang, Xilin; Pang, Ellie; Tsui, H Y; Wong, Eric; Wing, Yun Kwok

2005-03-01

To understand different aspects of community responses related to severe acute respiratory syndrome (SARS), 2 population-based, random telephone surveys were conducted in June 2003 and January 2004 in Hong Kong. More than 70% of respondents would avoid visiting hospitals or mainland China to avoid contracting SARS. Most respondents believed that SARS could be transmitted through droplets, fomites, sewage, and animals. More than 90% believed that public health measures were efficacious means of prevention; 40.4% believed that SARS would resurge in Hong Kong; and approximately equals 70% would then wear masks in public places. High percentages of respondents felt helpless, horrified, and apprehensive because of SARS. Approximately 16% showed signs of posttraumatic symptoms, and approximately equals 40% perceived increased stress in family or work settings. The general public in Hong Kong has been very vigilant about SARS but needs to be more psychologically prepared to face a resurgence of the epidemic.

SAR: Stroke Authorship Recognition

KAUST Repository

Shaheen, Sara; Rockwood, Alyn; Ghanem, Bernard

2015-01-01

Are simple strokes unique to the artist or designer who renders them? If so, can this idea be used to identify authorship or to classify artistic drawings? Also, could training methods be devised to develop particular styles? To answer these questions, we propose the Stroke Authorship Recognition (SAR) approach, a novel method that distinguishes the authorship of 2D digitized drawings. SAR converts a drawing into a histogram of stroke attributes that is discriminative of authorship. We provide extensive classification experiments on a large variety of data sets, which validate SAR's ability to distinguish unique authorship of artists and designers. We also demonstrate the usefulness of SAR in several applications including the detection of fraudulent sketches, the training and monitoring of artists in learning a particular new style and the first quantitative way to measure the quality of automatic sketch synthesis tools. © 2015 The Eurographics Association and John Wiley & Sons Ltd.

Perceptions of secondary technical schools students in Assiut, upper Egypt, about AIDS: Effect of an educational intervention

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Mohei El-Din A Selim

2010-01-01

Full Text Available Background and Purpose: Acquired Immunodeficiency Syndrome (AIDS is a great threat to the youth. The aim is to assess the knowledge of secondary technical schools students on AIDS, identify related misconceptions, and measure the effect of a short health education program on their level of knowledge. Materials and Methods: This quasi-experimental study was done on 575 secondary technical schools students in Assiut City, recruited through a two-stage stratified cluster sampling. A self-administered anonymous questionnaire was used to collect data. A health education program was implemented, and its effect assessed through pre-post testing. Results: The age range of the students was 16 to 20 years, with more girls (57.0%. Only 30.8% had satisfactory knowledge about AIDS in the pretest. Statistically significant improvements in knowledge were revealed after program implementation (P<0.001. Students who were Muslim, of urban residence, and had mobile phones had significantly higher scores (P=0.037, 0.004, 0.038 respectively. The most common misconceptions were the definition of AIDS according to transmission, and phobias related to transmission, which decreased after the intervention. Multivariate analysis showed that the statistically significant independent predictors of the change in knowledge score after the intervention were age, religion and the health education program. Conclusion: Secondary technical schools students in Assiut city have a major deficiency in knowledge and many misconceptions regarding AIDS. The educational intervention had a positive impact on their knowledge, but a less marked effect on misconceptions. Knowledge was affected by age and religious belief. It is recommended that more health educational efforts tailored to needs and with approaches suitable to community cultures and values be introduced.

Precision Rectification of Airborne SAR Image

DEFF Research Database (Denmark)

Dall, Jørgen; Liao, M.; Zhang, Zhe

1997-01-01

A simple and direct procedure for the rectification of a certain class of airborne SAR data is presented. The relief displacements of SAR data are effectively removed by means of a digital elevation model and the image is transformed to the ground coordinate system. SAR data from the Danish EMISAR...

Development and Evaluation of Science and Technology Education Program Using Interferometric SAR

Science.gov (United States)

Ito, Y.; Ikemitsu, H.; Nango, K.

2016-06-01

This paper proposes a science and technology education program to teach junior high school students to measure terrain changes by using interferometric synthetic aperture radar (SAR). The objectives of the proposed program are to evaluate and use information technology by performing SAR data processing in order to measure ground deformation, and to incorporate an understanding of Earth sciences by analyzing interferometric SAR processing results. To draft the teaching guidance plan for the developed education program, this study considers both science and technology education. The education program was used in a Japanese junior high school. An educational SAR processor developed by the authors and the customized Delft object-oriented radar interferometric software package were employed. Earthquakes as diastrophism events were chosen as practical teaching materials. The selected events indicate clear ground deformation in differential interferograms with high coherence levels. The learners were able to investigate the ground deformations and disasters caused by the events. They interactively used computers and became skilled at recognizing the knowledge and techniques of information technology, and then they evaluated the technology. Based on the results of pre- and post-questionnaire surveys and self-evaluation by the learners, it was clarified that the proposed program was applicable for junior high school education, and the learners recognized the usefulness of Earth observation technology by using interferometric SAR. The usefulness of the teaching materials in the learning activities was also shown through the practical teaching experience.

Non-U.S. Citizen, Community College Students: Their Federal Student Aid Status, Gender, Achievement, and Persistence at an Emerging HSI

Science.gov (United States)

Sanchez, Jafeth E.; Smith, Jeannette

2017-01-01

This study presents a quantitative, exploratory analysis of 535 students attending Truckee Meadows Community College in Northern Nevada who were eligible or ineligible for federal student aid and were non-U.S. citizens. Within a snapshot of the Fall 2015 through Fall 2016 semesters, we examined the variables of gender, grade point average (GPA),…

SARS: systematic review of treatment effects.

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Lauren J Stockman

2006-09-01

Full Text Available BACKGROUND: The SARS outbreak of 2002-2003 presented clinicians with a new, life-threatening disease for which they had no experience in treating and no research on the effectiveness of treatment options. The World Health Organization (WHO expert panel on SARS treatment requested a systematic review and comprehensive summary of treatments used for SARS-infected patients in order to guide future treatment and identify priorities for research. METHODS AND FINDINGS: In response to the WHO request we conducted a systematic review of the published literature on ribavirin, corticosteroids, lopinavir and ritonavir (LPV/r, type I interferon (IFN, intravenous immunoglobulin (IVIG, and SARS convalescent plasma from both in vitro studies and in SARS patients. We also searched for clinical trial evidence of treatment for acute respiratory distress syndrome. Sources of data were the literature databases MEDLINE, EMBASE, BIOSIS, and the Cochrane Central Register of Controlled Trials (CENTRAL up to February 2005. Data from publications were extracted and evidence within studies was classified using predefined criteria. In total, 54 SARS treatment studies, 15 in vitro studies, and three acute respiratory distress syndrome studies met our inclusion criteria. Within in vitro studies, ribavirin, lopinavir, and type I IFN showed inhibition of SARS-CoV in tissue culture. In SARS-infected patient reports on ribavirin, 26 studies were classified as inconclusive, and four showed possible harm. Seven studies of convalescent plasma or IVIG, three of IFN type I, and two of LPV/r were inconclusive. In 29 studies of steroid use, 25 were inconclusive and four were classified as causing possible harm. CONCLUSIONS: Despite an extensive literature reporting on SARS treatments, it was not possible to determine whether treatments benefited patients during the SARS outbreak. Some may have been harmful. Clinical trials should be designed to validate a standard protocol for dosage

77 FR 48507 - Proposed Information Collection Requests; Federal Student Aid; Foreign School Supplemental...

Science.gov (United States)

2012-08-14

... Application System. OMB Control Number: Pending. Type of Review: New. Total Estimated Number of Annual... Student Aid and who have been issued the required two factor authentication tokens can access the FS SAS...

SARS knowledge, perceptions, and behaviors: a comparison between Finns and the Dutch during the SARS outbreak in 2003

NARCIS (Netherlands)

Vartti, A.M.; Oenema, A.; Schreck, M.; Uutela, A.; Zwart, de O.; Brug, J.; Aro, A.R.

2009-01-01

BACKGROUND: The SARS outbreak served to test both local and international outbreak management and risk communication practices. PURPOSE: The study compares SARS knowledge, perceptions, behaviors, and information between Finns and the Dutch during the SARS outbreak in 2003. METHOD: The participants

MULTI-TEMPORAL SAR INTERFEROMETRY FOR LANDSLIDE MONITORING

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R. Dwivedi

2016-06-01

Full Text Available In the past few years, SAR Interferometry specially InSAR and D-InSAR were extensively used for deformation monitoring related applications. Due to temporal and spatial decorrelation in dense vegetated areas, effectiveness of InSAR and D-InSAR observations were always under scrutiny. Multi-temporal InSAR methods are developed in recent times to retrieve the deformation signal from pixels with different scattering characteristics. Presently, two classes of multi-temporal InSAR algorithms are available- Persistent Scatterer (PS and Small Baseline (SB methods. This paper discusses the Stanford Method for Persistent Scatterer (StaMPS based PS-InSAR and the Small Baselines Subset (SBAS techniques to estimate the surface deformation in Tehri dam reservoir region in Uttarkhand, India. Both PS-InSAR and SBAS approaches used sixteen ENVISAT ASAR C-Band images for generating single master and multiple master interferograms stack respectively and their StaMPS processing resulted in time series 1D-Line of Sight (LOS mean velocity maps which are indicative of deformation in terms of movement towards and away from the satellites. From 1D LOS velocity maps, localization of landslide is evident along the reservoir rim area which was also investigated in the previous studies. Both PS-InSAR and SBAS effectively extract measurement pixels in the study region, and the general results provided by both approaches show a similar deformation pattern along the Tehri reservoir region. Further, we conclude that StaMPS based PS-InSAR method performs better in terms of extracting more number of measurement pixels and in the estimation of mean Line of Sight (LOS velocity as compared to SBAS method. It is also proposed to take up a few major landslides area in Uttarakhand for slope stability assessment.

SARS: Key factors in crisis management.

Science.gov (United States)

Tseng, Hsin-Chao; Chen, Thai-Form; Chou, Shieu-Ming

2005-03-01

This study was conducted at a single hospital selected in Taipei during the SARS (Severe Acute Respiratory Syndrome) outbreak from March to July, 2003 in Taiwan. During this period of time, 104 SARS patients were admitted to the hospital. There were no negative reports related to the selected hospital despite its being located right in the center of an area struck by the epidemic. The purpose of this study was to identify the key factors enabling the hospital to survive SARS unscathed. Data were collected from in-depth interviews with the nursing directors and nursing managers of the SARS units, along with a review of relevant hospital documents. The five key elements identified as survival factors during this SARS crisis are as follows: 1. good control of timing for crisis management, 2. careful decision-making, 3. thorough implementation, 4. effective communication, and 5. trust between management and employees. The results of this study reconfirmed the selected hospital as a model for good crisis management during the SARS epidemic.

UAVSAR and TerraSAR-X Based InSAR Detection of Localized Subsidence in the New Orleans Area

Science.gov (United States)

Blom, R. G.; An, K.; Jones, C. E.; Latini, D.

2014-12-01

Vulnerability of the US Gulf coast to inundation has received increased attention since hurricanes Katrina and Rita. Compounding effects of sea level rise, wetland loss, and regional and local subsidence makes flood protection a difficult challenge, and particularly for the New Orleans area. Key to flood protection is precise knowledge of elevations and elevation changes. Analysis of historical and continuing geodetic measurements show surprising complexity, including locations subsiding more rapidly than considered during planning of hurricane protection and coastal restoration projects. Combining traditional, precise geodetic data with interferometric synthetic aperture radar (InSAR) observations can provide geographically dense constraints on surface deformation. The Gulf Coast environment is challenging for InSAR techniques, especially with systems not designed for interferometry. We use two InSAR capable systems, the L- band (24 cm wavelength) airborne JPL/NASA UAVSAR, and the DLR/EADS Astrium spaceborne TerraSAR X-band (3 cm wavelength), and compare results. First, we are applying pair-wise InSAR to the longer wavelength UAVSAR data to detect localized elevation changes potentially impacting flood protection infrastructure from 2009 - 2014. We focus on areas on and near flood protection infrastructure to identify changes indicative of subsidence, structural deformation, and/or seepage. The Spaceborne TerraSAR X-band SAR system has relatively frequent observations, and dense persistent scatterers in urban areas, enabling measurement of very small displacements. We compare L-band UAVSAR results with permanent scatterer (PS-InSAR) and Short Baseline Subsets (SBAS) interferometric analyses of a stack composed by 28 TerraSAR X-band images acquired over the same period. Thus we can evaluate results from the different radar frequencies and analyses techniques. Preliminary results indicate subsidence features potentially of a variety of causes, including ground water

Student Aids and BBCCS (B'nai B'rith Career and Counseling Service): A New Look at an Old Problem.

Science.gov (United States)

Feingold, S. Norman

Approximately 95 percent of affiliated Jewish youth attend college. Much is happening in student aid today that will probably affect parents and their children. Issues of importance include: (1) legal considerations; (2) sources of financial aid; (3) applying for financial aid; (4) state and federal programs of financial aid; (5) sources of…

SAR Raw Data Generation for Complex Airport Scenes

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Jia Li

2014-10-01

Full Text Available The method of generating the SAR raw data of complex airport scenes is studied in this paper. A formulation of the SAR raw signal model of airport scenes is given. Via generating the echoes from the background, aircrafts and buildings, respectively, the SAR raw data of the unified SAR imaging geometry is obtained from their vector additions. The multipath scattering and the shadowing between the background and different ground covers of standing airplanes and buildings are analyzed. Based on the scattering characteristics, coupling scattering models and SAR raw data models of different targets are given, respectively. A procedure is given to generate the SAR raw data of airport scenes. The SAR images from the simulated raw data demonstrate the validity of the proposed method.

SAR-aided method for rural soil evaluation

Science.gov (United States)

Lay-Ekuakille, Aime; Dellisanti, Carmelo; Pelillo, Vincenza; Tralli, Francesco

2003-03-01

The principal land characteristics that can be estimated by means of airphoto interpretation are bedrock type, landform, soil texture, site drainage conditions, susceptibility to flooding, and depth of unconsolidated materials over bedrock. In addition, the slope of the land surface can be estimated by airphoto interpretation and measured by phptpgrammetric methods. The aim of this paper is to show an experimental use of satellite images in determining soil quality affected by anthropic activities as rock crushing, or scarifying. Scarifying activities began, in Murgia area, Apulia Region, Italy), as land improvement for agriculture uses. Scarifying is defined as loosening (the surface of soil) by using an agricultural tool or a machine with prongs. This kind of activity is facilitated by the availability, on the market, of scarifying machines and the objective is to get a stratum of agriculture-useful loose material on the soil surface. Apulia Region Government has permitted calcareous stone scarifying with Regional Law n.54 (August 31, 1981) according to National Law n.984 (Dicember 27,1977), that provides for encouraging to transform grazing in sown land in order to create new possibility of forage production to increase zootecnical facilities. We have used ERS-2/SAR images as contribution in the process of soil characterization.The area we have considered is in Puglia Region and is subject to soil transformation due to rocks crushed on land for agricultural facilities. European Union, through the same Apulia Region Government, has renewed funds for the improvement of meadow and grazing for an overall surface of 2000 hectares. In this way it is clear to understand the importance of qualitative and quantitative evaluation of rock crushing or scarifying by using airphoto interpretation. We have evaluated the soil quality by introducing a multicriteria, analysis by using a qualitative and quantitative methodology, so that it will be possible to prevent damages on

Perceptions of secondary technical schools students in Assiut, upper Egypt, about AIDS: Effect of an educational intervention.

Science.gov (United States)

Selim, Mohei El-Din A; El-Shereef, Etemad A A

2010-01-01

Acquired Immunodeficiency Syndrome (AIDS) is a great threat to the youth. The aim is to assess the knowledge of secondary technical schools students on AIDS, identify related misconceptions, and measure the effect of a short health education program on their level of knowledge. This quasi-experimental study was done on 575 secondary technical schools students in Assiut City, recruited through a two-stage stratified cluster sampling. A self-administered anonymous questionnaire was used to collect data. A health education program was implemented, and its effect assessed through pre-post testing. The age range of the students was 16 to 20 years, with more girls (57.0%). Only 30.8% had satisfactory knowledge about AIDS in the pretest. Statistically significant improvements in knowledge were revealed after program implementation (PStudents who were Muslim, of urban residence, and had mobile phones had significantly higher scores (P=0.037, 0.004, 0.038 respectively). The most common misconceptions were the definition of AIDS according to transmission, and phobias related to transmission, which decreased after the intervention. Multivariate analysis showed that the statistically significant independent predictors of the change in knowledge score after the intervention were age, religion and the health education program. Secondary technical schools students in Assiut city have a major deficiency in knowledge and many misconceptions regarding AIDS. The educational intervention had a positive impact on their knowledge, but a less marked effect on misconceptions. Knowledge was affected by age and religious belief. It is recommended that more health educational efforts tailored to needs and with approaches suitable to community cultures and values be introduced.

Deep learning for SAR image formation

Science.gov (United States)

Mason, Eric; Yonel, Bariscan; Yazici, Birsen

2017-04-01

The recent success of deep learning has lead to growing interest in applying these methods to signal processing problems. This paper explores the applications of deep learning to synthetic aperture radar (SAR) image formation. We review deep learning from a perspective relevant to SAR image formation. Our objective is to address SAR image formation in the presence of uncertainties in the SAR forward model. We present a recurrent auto-encoder network architecture based on the iterative shrinkage thresholding algorithm (ISTA) that incorporates SAR modeling. We then present an off-line training method using stochastic gradient descent and discuss the challenges and key steps of learning. Lastly, we show experimentally that our method can be used to form focused images in the presence of phase uncertainties. We demonstrate that the resulting algorithm has faster convergence and decreased reconstruction error than that of ISTA.

A Self-Instructional Course in Student Financial Aid Administration. Module 3: The Legislative and Regulatory Processes. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The third of a 17-module self-instructional course on student financial aid administration, this module offers a systematic introduction to the management of federal financial aid programs authorized by Title IV of the Higher Education Act to novice financial aid administrators and other institutional personnel. It teaches the administrator to…

Assessment of the knowledge and attitudes regarding HIV/AIDS among pre-clinical medical students in Israel

Science.gov (United States)

2014-01-01

Background Today’s medical students are the future physicians of people living with HIV/AIDS (PLWHA). It is therefore essential that medical students possess the appropriate knowledge and attitudes regarding PLWHA. This study aims to evaluate knowledge and attitudes of pre-clinical Israeli medical students and to assess whether their knowledge and attitudes change throughout their pre-clinical studies. Methods A cross-sectional study was conducted among all pre-clinical medical students from the four medical schools in Israel during the academic year of 2010/2011 (a total of 1,470 students). A self-administered questionnaire was distributed. The questionnaire sought student responses pertaining to knowledge of HIV transmission and non-transmission routes, basic knowledge of HIV/AIDS treatment and attitudes towards HIV/AIDS. Results The study’s response rate was 62.24 percent. Knowledge among pre-clinical medical students was generally high and showed a statistically significant improvement as students progressed through their pre-clinical studies. However, there were some misconceptions, mostly regarding HIV transmission via breastfeeding and knowledge of HIV prevention after exposure to the virus. Students’ attitudes were found to include stigmatizing notions. Furthermore, the majority of medical students correlated HIV with shame and fear. In addition, students’ attitudes toward HIV testing and providing confidential medical information were contradictory to health laws, protocols and guidelines. Overall, no positive changes in students’ attitudes were observed during the pre-clinical years of medical school. Conclusion The knowledge of pre-clinical medical students in Israel is generally high, although there are some knowledge inadequacies that require more emphasis in the curricula of the medical schools. Contrary to HIV-related knowledge, medical students’ attitudes are unaffected by their progression through medical school. Therefore, medical

A pilot randomised controlled study of the mental health first aid eLearning course with UK medical students.

Science.gov (United States)

Davies, E Bethan; Beever, Emmeline; Glazebrook, Cris

2018-03-21

Medical students face many barriers to seeking out professional help for their mental health, including stigma relating to mental illness, and often prefer to seek support and advice from fellow students. Improving medical students' mental health literacy and abilities to support someone experiencing a mental health problem could reduce barriers to help seeking and improve mental health in this population. Mental Health First Aid (MHFA) is an evidence-based intervention designed to improve mental health literacy and ability to respond to someone with a mental health problem. This pilot randomised controlled trial aims to evaluate the MHFA eLearning course in UK medical students. Fifty-five medical students were randomised to receive six weeks access to the MHFA eLearning course (n = 27) or to a no-access control group (n = 28). Both groups completed baseline (pre-randomisation) and follow-up (six weeks post-randomisation) online questionnaires measuring recognition of a mental health problem, mental health first aid intentions, confidence to help a friend experiencing a mental health problem, and stigmatising attitudes. Course feedback was gathered at follow-up. More participants were lost follow-up in the MHFA group (51.9%) compared to control (21.4%). Both intention-to-treat (ITT) and non-ITT analyses showed that the MHFA intervention improved mental health first aid intentions (p = first aid actions at follow-up (p = .006). Feedback about the MHFA course was generally positive, with participants stating it helped improve their knowledge and confidence to help someone. This pilot study demonstrated the potential for the MHFA eLearning course to improve UK medical students' mental health first aid skills, confidence to help a friend and stigmatising attitudes. It could be useful in supporting their own and others' mental health while studying and in their future healthcare careers. Retrospectively registered ( ISRCTN11219848 ).

Attitude of medical students towards the use of audio visual aids during didactic lectures in pharmacology in a medical college of central India

OpenAIRE

Mehul Agrawal; Rajanish Kumar Sankdia

2016-01-01

Background: Students favour teaching methods employing audio visual aids over didactic lectures not using these aids. However, the optimum use of audio visual aids is essential for deriving their benefits. During a lecture, both the visual and auditory senses are used to absorb information. Different methods of lecture are and ndash; chalk and board, power point presentations (PPT) and mix of aids. This study was done to know the students' preference regarding the various audio visual aids, ...

Marketing Financial Aid

Science.gov (United States)

Huddleston, Thomas, Jr.; Batty, Burt F.

1978-01-01

Student financial assistance services are becoming a major part of the institutional marketing plan as traditional college-age students decline in numbers and price competition among institutions increases. The effect of financial aid on enrollment and admissions processes is discussed along with the role of the financial aid officer. (Author/LBH)

Mental health first aid training for Australian medical and nursing students: an evaluation study

OpenAIRE

Bond, Kathy S; Jorm, Anthony F; Kitchener, Betty A; Reavley, Nicola J

2015-01-01

Background The role and demands of studying nursing and medicine involve specific stressors that may contribute to an increased risk for mental health problems. Stigma is a barrier to help-seeking for mental health problems in nursing and medical students, making these students vulnerable to negative outcomes including higher failure rates and discontinuation of study. Mental Health First Aid (MHFA) is a potential intervention to increase the likelihood that medical and nursing students will ...

Low-SAR metamaterial-inspired printed monopole antenna

Science.gov (United States)

Hossain, M. I.; Faruque, M. R. I.; Islam, M. T.; Ali, M. T.

2017-01-01

In this paper, a low-SAR metamaterial-embedded planar monopole antenna is introduced for a wireless communication system. A printed monopole antenna is designed for modern mobile, which operates in GSM, UMTS, LTE, WLAN, and Bluetooth frequency bands. A metamaterial structure is designed to use in the mobile handset with a multi-band printed monopole antenna. The finite integration technique of the CST microwave studio is used in this study. The measurement of antenna performances is taken in an anechoic chamber, and the SAR values are measured using COMOSAR system. The results indicate that metamaterial structure leads to reduce SAR without affecting antenna performance significantly. According to the measured results, the metamaterial attachment leads to reduce 87.7% peak SAR, 68.2% 1-g SAR, and 46.78% 10-g SAR compared to antenna without metamaterial.

Effectiveness of first-aid training on school students in Singur Block of Hooghly District, West Bengal.

Science.gov (United States)

Bandyopadhyay, Lina; Manjula, M; Paul, Bobby; Dasgupta, Aparajita

2017-01-01

First aid is the helping behavior and initial care provided for an acute illness or injury. Students have the potential for changing the health scenario of the society if properly groomed and educated. The objective of the study is to evaluate the effectiveness of educational intervention on the first aid among middle school students of a rural school in West Bengal. A total of 230, 6 th and 7 th standard students were given a self-administered questionnaire for assessing their baseline knowledge about management of common injuries followed by educational intervention with a systematically devised teaching module during February to March 2016. Post intervention evaluation of their knowledge acquisition was done after 2 weeks with same questionnaire. The baseline knowledge on the management of selected injuries was found to be insufficient among the study subjects. Paired t -test was performed to compare the pre- and post-test scores of knowledge and attitude of the students about first aid, and there was a significant change in knowledge from pretest score (mean = 1.50, standard deviation [SD] =0.47) to posttest score (mean = 6.53, SD = 1.30). To quantify the effectiveness of health education, effect size (Cohen's d) was derived. For knowledge score, Cohen's d was 5.14 with large effect size indicating highly effective impact of the training program. Significant change was also noticed regarding attitude regarding first aid as evident from increase in pretest score (mean = 1.19, SD = 0.96) to posttest score (mean = 3.17, SD = 1.03); Cohen's d was 1.88 with medium effect size. Inculcating first-aid training in the school curriculum can be a fruitful investment in ensuring proper and timely management of illnesses and injuries not only for the school children but also for the community at large.

Effectiveness of first-aid training on school students in Singur Block of Hooghly District, West Bengal

Directory of Open Access Journals (Sweden)

Lina Bandyopadhyay

2017-01-01

Full Text Available Objective: First aid is the helping behavior and initial care provided for an acute illness or injury. Students have the potential for changing the health scenario of the society if properly groomed and educated. The objective of the study is to evaluate the effectiveness of educational intervention on the first aid among middle school students of a rural school in West Bengal. Materials and Methods: A total of 230, 6th and 7th standard students were given a self-administered questionnaire for assessing their baseline knowledge about management of common injuries followed by educational intervention with a systematically devised teaching module during February to March 2016. Post intervention evaluation of their knowledge acquisition was done after 2 weeks with same questionnaire. Results: The baseline knowledge on the management of selected injuries was found to be insufficient among the study subjects. Paired t-test was performed to compare the pre- and post-test scores of knowledge and attitude of the students about first aid, and there was a significant change in knowledge from pretest score (mean = 1.50, standard deviation [SD] =0.47 to posttest score (mean = 6.53, SD = 1.30. To quantify the effectiveness of health education, effect size (Cohen's d was derived. For knowledge score, Cohen's d was 5.14 with large effect size indicating highly effective impact of the training program. Significant change was also noticed regarding attitude regarding first aid as evident from increase in pretest score (mean = 1.19, SD = 0.96 to posttest score (mean = 3.17, SD = 1.03; Cohen's d was 1.88 with medium effect size. Conclusion: Inculcating first-aid training in the school curriculum can be a fruitful investment in ensuring proper and timely management of illnesses and injuries not only for the school children but also for the community at large.

A NEW SAR CLASSIFICATION SCHEME FOR SEDIMENTS ON INTERTIDAL FLATS BASED ON MULTI-FREQUENCY POLARIMETRIC SAR IMAGERY

Directory of Open Access Journals (Sweden)

W. Wang

2017-11-01

Full Text Available We present a new classification scheme for muddy and sandy sediments on exposed intertidal flats, which is based on synthetic aperture radar (SAR data, and use ALOS-2 (L-band, Radarsat-2 (C-band and TerraSAR-X (X-band fully polarimetric SAR imagery to demonstrate its effectiveness. Four test sites on the German North Sea coast were chosen, which represent typical surface compositions of different sediments, vegetation, and habitats, and of which a large amount of SAR is used for our analyses. Both Freeman-Durden and Cloude-Pottier polarimetric decomposition are utilized, and an additional descriptor called Double-Bounce Eigenvalue Relative Difference (DERD is introduced into the feature sets instead of the original polarimetric intensity channels. The classification is conducted following Random Forest theory, and the results are verified using ground truth data from field campaigns and an existing classification based on optical imagery. In addition, the use of Kennaugh elements for classification purposes is demonstrated using both fully and dual-polarization multi-frequency and multi-temporal SAR data. Our results show that the proposed classification scheme can be applied for the discrimination of muddy and sandy sediments using L-, C-, and X-band SAR images, while SAR imagery acquired at short wavelengths (C- and X-band can also be used to detect more detailed features such as bivalve beds on intertidal flats.

Knowledge of First Aid Skills Among Students of a Medical College in Mangalore City of South India

OpenAIRE

Joseph, N; Kumar, GS; Babu, YPR; Nelliyanil, M; Bhaskaran, U

2014-01-01

Background: The adequate knowledge required for handling an emergency without hospital setting at the site of the accident or emergency may not be sufficient as most medical schools do not have formal first aid training in the teaching curriculum. Aim: The aim of this study is to assess the level of knowledge of medical students in providing first aid care. Subjects and Methods: This cross-sectional study was conducted during May 2011 among 152 medical students. Data was collected using a sel...

77 FR 24690 - Notice of Proposed Information Collection Requests; Federal Student Aid; Pell Grant, ACG, and...

Science.gov (United States)

2012-04-25

... DEPARTMENT OF EDUCATION Notice of Proposed Information Collection Requests; Federal Student Aid; Pell Grant, ACG, and National SMART Reporting Under the Common Origination and Disbursement (COD) System SUMMARY: The Federal Pell Grant, ACG, and National SMART Programs are student financial assistance...

Exploring the Effects of Financial Aid on the Gap in Student Dropout Risks by Income Level

Science.gov (United States)

Chen, Rong; DesJardins, Stephen L.

2008-01-01

Using national survey data and discrete-time logit modeling, this research seeks to understand whether student aid mediates the relationship between parental income and student dropout behavior. Our analysis confirms that there is a gap in dropout rates for low-income students compared with their upper income peers, and suggests that some types of…

The SARS-unique domain (SUD of SARS coronavirus contains two macrodomains that bind G-quadruplexes.

Directory of Open Access Journals (Sweden)

Jinzhi Tan

2009-05-01

Full Text Available Since the outbreak of severe acute respiratory syndrome (SARS in 2003, the three-dimensional structures of several of the replicase/transcriptase components of SARS coronavirus (SARS-CoV, the non-structural proteins (Nsps, have been determined. However, within the large Nsp3 (1922 amino-acid residues, the structure and function of the so-called SARS-unique domain (SUD have remained elusive. SUD occurs only in SARS-CoV and the highly related viruses found in certain bats, but is absent from all other coronaviruses. Therefore, it has been speculated that it may be involved in the extreme pathogenicity of SARS-CoV, compared to other coronaviruses, most of which cause only mild infections in humans. In order to help elucidate the function of the SUD, we have determined crystal structures of fragment 389-652 ("SUD(core" of Nsp3, which comprises 264 of the 338 residues of the domain. Both the monoclinic and triclinic crystal forms (2.2 and 2.8 A resolution, respectively revealed that SUD(core forms a homodimer. Each monomer consists of two subdomains, SUD-N and SUD-M, with a macrodomain fold similar to the SARS-CoV X-domain. However, in contrast to the latter, SUD fails to bind ADP-ribose, as determined by zone-interference gel electrophoresis. Instead, the entire SUD(core as well as its individual subdomains interact with oligonucleotides known to form G-quadruplexes. This includes oligodeoxy- as well as oligoribonucleotides. Mutations of selected lysine residues on the surface of the SUD-N subdomain lead to reduction of G-quadruplex binding, whereas mutations in the SUD-M subdomain abolish it. As there is no evidence for Nsp3 entering the nucleus of the host cell, the SARS-CoV genomic RNA or host-cell mRNA containing long G-stretches may be targets of SUD. The SARS-CoV genome is devoid of G-stretches longer than 5-6 nucleotides, but more extended G-stretches are found in the 3'-nontranslated regions of mRNAs coding for certain host-cell proteins

SAR Image Classification Based on Its Texture Features

Institute of Scientific and Technical Information of China (English)

LI Pingxiang; FANG Shenghui

2003-01-01

SAR images not only have the characteristics of all-ay, all-eather, but also provide object information which is different from visible and infrared sensors. However, SAR images have some faults, such as more speckles and fewer bands. The authors conducted the experiments of texture statistics analysis on SAR image features in order to improve the accuracy of SAR image interpretation.It is found that the texture analysis is an effective method for improving the accuracy of the SAR image interpretation.

Financial Aid Policy: Lessons from Research

Science.gov (United States)

Dynarski, Susan; Scott-Clayton, Judith

2013-01-01

In the nearly fifty years since the adoption of the Higher Education Act of 1965, financial aid programs have grown in scale, expanded in scope, and multiplied in form. As a result, financial aid has become the norm among college enrollees. Aid now flows not only to traditional college students but also to part-time students, older students, and…

77 FR 45592 - Notice of Submission for OMB Review; Federal Student Aid; Federal Perkins Loan Program Master...

Science.gov (United States)

2012-08-01

... loans for eligible students to pay the costs of a student's attendance at an eligible institution of... DEPARTMENT OF EDUCATION Notice of Submission for OMB Review; Federal Student Aid; Federal Perkins... technology. Please note that written comments received in response to this notice will be considered public...

Guia para estudiantes: Ayuda economica del Departamento de Educacion de los Estados Unidos, 2003-2004 (The Student Guide: Financial Aid from the U.S. Department of Education, 2003-2004).

Science.gov (United States)

Office of Federal Student Aid (ED), Washington, DC.

This Spanish language publication explains what federal student financial aid is and the types of student financial aid that are available. The guide opens with an overview of federal student financial aid, and then discusses how to find out about student aid. A section of general information discusses eligibility and dependency. Types of federal…

The Ecosystems SAR (EcoSAR) an Airborne P-band Polarimetric InSAR for the Measurement of Vegetation Structure, Biomass and Permafrost

Science.gov (United States)

Rincon, Rafael F.; Fatoyinbo, Temilola; Ranson, K. Jon; Osmanoglu, Batuhan; Sun, Guoqing; Deshpande, Manohar D.; Perrine, Martin L.; Du Toit, Cornelis F.; Bonds, Quenton; Beck, Jaclyn;

FlexSAR, a high quality, flexible, cost effective, prototype SAR system

Science.gov (United States)

Jensen, Mark; Knight, Chad; Haslem, Brent

2016-05-01

The FlexSAR radar system was designed to be a high quality, low-cost, flexible research prototype instrument. Radar researchers and practitioners often desire the ability to prototype new or advanced configurations, yet the ability to enhance or upgrade existing radar systems can be cost prohibitive. FlexSAR answers the need for a flexible radar system that can be extended easily, with minimal cost and time expenditures. The design approach focuses on reducing the resources required for developing and validating new advanced radar modalities. Such an approach fosters innovation and provides risk reduction since actual radar data can be collected in the appropriate mode, processed, and analyzed early in the development process. This allows for an accurate, detailed understanding of the corresponding trade space. This paper is a follow-on to last years paper and discusses the advancements that have been made to the FlexSAR system. The overall system architecture is discussed and presented along with several examples illustrating the system utility.

InSAR Deformation Time Series Processed On-Demand in the Cloud

Science.gov (United States)

Horn, W. B.; Weeden, R.; Dimarchi, H.; Arko, S. A.; Hogenson, K.

2017-12-01

During this past year, ASF has developed a cloud-based on-demand processing system known as HyP3 (http://hyp3.asf.alaska.edu/), the Hybrid Pluggable Processing Pipeline, for Synthetic Aperture Radar (SAR) data. The system makes it easy for a user who doesn't have the time or inclination to install and use complex SAR processing software to leverage SAR data in their research or operations. One such processing algorithm is generation of a deformation time series product, which is a series of images representing ground displacements over time, which can be computed using a time series of interferometric SAR (InSAR) products. The set of software tools necessary to generate this useful product are difficult to install, configure, and use. Moreover, for a long time series with many images, the processing of just the interferograms can take days. Principally built by three undergraduate students at the ASF DAAC, the deformation time series processing relies the new Amazon Batch service, which enables processing of jobs with complex interconnected dependencies in a straightforward and efficient manner. In the case of generating a deformation time series product from a stack of single-look complex SAR images, the system uses Batch to serialize the up-front processing, interferogram generation, optional tropospheric correction, and deformation time series generation. The most time consuming portion is the interferogram generation, because even for a fairly small stack of images many interferograms need to be processed. By using AWS Batch, the interferograms are all generated in parallel; the entire process completes in hours rather than days. Additionally, the individual interferograms are saved in Amazon's cloud storage, so that when new data is acquired in the stack, an updated time series product can be generated with minimal addiitonal processing. This presentation will focus on the development techniques and enabling technologies that were used in developing the time

Convolutional Neural Networks for SAR Image Segmentation

DEFF Research Database (Denmark)

Malmgren-Hansen, David; Nobel-Jørgensen, Morten

2015-01-01

Segmentation of Synthetic Aperture Radar (SAR) images has several uses, but it is a difficult task due to a number of properties related to SAR images. In this article we show how Convolutional Neural Networks (CNNs) can easily be trained for SAR image segmentation with good results. Besides...

Teaching Modules to Build HIV/AIDS Knowledge and Safer Sex Skills among African-American College Students

Science.gov (United States)

Kanekar, Amar; Sharma, Manoj

2011-01-01

The HIV/AIDS epidemic has taken a tremendous toll on the population of the United States. College students, including African-Americans aged 13-24 years, across the nation are susceptible to contracting sexually transmitted diseases including HIV/AIDS as they participate in unsafe sex practices. The purpose of this article is to provide teaching…

Visible Earthquakes: a web-based tool for visualizing and modeling InSAR earthquake data

Science.gov (United States)

Funning, G. J.; Cockett, R.

2012-12-01

InSAR (Interferometric Synthetic Aperture Radar) is a technique for measuring the deformation of the ground using satellite radar data. One of the principal applications of this method is in the study of earthquakes; in the past 20 years over 70 earthquakes have been studied in this way, and forthcoming satellite missions promise to enable the routine and timely study of events in the future. Despite the utility of the technique and its widespread adoption by the research community, InSAR does not feature in the teaching curricula of most university geoscience departments. This is, we believe, due to a lack of accessibility to software and data. Existing tools for the visualization and modeling of interferograms are often research-oriented, command line-based and/or prohibitively expensive. Here we present a new web-based interactive tool for comparing real InSAR data with simple elastic models. The overall design of this tool was focused on ease of access and use. This tool should allow interested nonspecialists to gain a feel for the use of such data and greatly facilitate integration of InSAR into upper division geoscience courses, giving students practice in comparing actual data to modeled results. The tool, provisionally named 'Visible Earthquakes', uses web-based technologies to instantly render the displacement field that would be observable using InSAR for a given fault location, geometry, orientation, and slip. The user can adjust these 'source parameters' using a simple, clickable interface, and see how these affect the resulting model interferogram. By visually matching the model interferogram to a real earthquake interferogram (processed separately and included in the web tool) a user can produce their own estimates of the earthquake's source parameters. Once satisfied with the fit of their models, users can submit their results and see how they compare with the distribution of all other contributed earthquake models, as well as the mean and median

PHARUS : PHased ARray Universal SAR

NARCIS (Netherlands)

Paquay, M.H.A.; Vermeulen, B.C.B.; Koomen, P.J.; Hoogeboom, P.; Snoeij, P.; Pouwels, H.

1996-01-01

In the Netherlands, a polarimetric C-band aircraft SAR (Synthetic Aperture Radar) has been developed. The project is called PHARUS, an acronm for PHased ARray Universal SAR. This instrument serves remote sensing applications. The antenna system contains 48 active modules (expandable to 96). A module

Spaceborne Polarimetric SAR Interferometry: Performance Analysis and Mission Concepts

Directory of Open Access Journals (Sweden)

Shane R. Cloude

2005-12-01

Full Text Available We investigate multichannel imaging radar systems employing coherent combinations of polarimetry and interferometry (Pol-InSAR. Such systems are well suited for the extraction of bio- and geophysical parameters by evaluating the combined scattering from surfaces and volumes. This combination leads to several important differences between the design of Pol-InSAR sensors and conventional single polarisation SAR interferometers. We first highlight these differences and then investigate the Pol-InSAR performance of two proposed spaceborne SAR systems (ALOS/PalSAR and TerraSAR-L operating in repeat-pass mode. For this, we introduce the novel concept of a phase tube which enables (1 a quantitative assessment of the Pol-InSAR performance, (2 a comparison between different sensor configurations, and (3 an optimization of the instrument settings for different Pol-InSAR applications. The phase tube may hence serve as an interface between system engineers and application-oriented scientists. The performance analysis reveals major limitations for even moderate levels of temporal decorrelation. Such deteriorations may be avoided in single-pass sensor configurations and we demonstrate the potential benefits from the use of future bi- and multistatic SAR interferometers.

SARS-related Perceptions in Hong Kong

OpenAIRE

Lau, Joseph T.F.; Yang, Xilin; Pang, Ellie; Tsui, H.Y.; Wong, Eric; Wing, Yun Kwok

2005-01-01

To understand different aspects of community responses related to severe acute respiratory syndrome (SARS), 2 population-based, random telephone surveys were conducted in June 2003 and January 2004 in Hong Kong. More than 70% of respondents would avoid visiting hospitals or mainland China to avoid contracting SARS. Most respondents believed that SARS could be transmitted through droplets, fomites, sewage, and animals. More than 90% believed that public health measures were efficacious means o...

HIV and AIDS related knowledge, sources of information, and reported need for further education among dental students in Sudan- a cross sectional study

Directory of Open Access Journals (Sweden)

Åstrøm Anne

2008-08-01

Full Text Available Abstract Background Information on the HIV and AIDS-related knowledge among dental students provides a crucial foundation for efforts aimed at developing an appropriate dental curriculum on HIV and AIDS, and for attracting the attention of dental school educators towards the subject. Purposes Focusing on a census of dental students attending their 3rd, 4th and 5th study year at publicly – and privately funded dental faculties in Khartoum, this study aimed to assess the prevalence and socio-economic correlates of dental students' knowledge, sources of information and reported need for further education related to HIV and AIDS. Methods At the time of the survey (March–May 2007, the total number of dental students registered was 782 of which 642 (response rate 82%, mean age 21.7 year, 72% girls completed anonymous self-administered questionnaires in supervised class room settings. Results A total of 49% and 86% had correct sum scores with respect to knowledge of transmission through contamination and through shaking hands and eating, respectively. About half the dental students recognized a need for further education across HIV related issues, varying from 75% (basic HIV/AIDS related issues to 84% (patient management. Only 38% of the students had correct sum scores regarding various occupational groups at risk for contacting HIV and AIDS. Multiple logistic regression analysis revealed that compared to privately funded dental school students, publicly funded dental school students were less likely to have correct knowledge about modes of HIV transmission (OR = 0.6 and occupational risk groups (OR = 0.6 and to have received information from lectures/health care workers (OR = 0.5. Conclusion Students attending privately funded schools were more knowledgeable about various HIV related issues than students from publicly funded schools. About half of the students investigated had received HIV/AIDS information from various sources and reported need

Genome organization of the SARS-CoV

DEFF Research Database (Denmark)

Xu, Jing; Hu, Jianfei; Wang, Jing

2003-01-01

Annotation of the genome sequence of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) is indispensable to understand its evolution and pathogenesis. We have performed a full annotation of the SARS-CoV genome sequences by using annotation programs publicly available or devel......Annotation of the genome sequence of the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) is indispensable to understand its evolution and pathogenesis. We have performed a full annotation of the SARS-CoV genome sequences by using annotation programs publicly available...

SARS-coronavirus replication is supported by a reticulovesicular network of modified endoplasmic reticulum.

Directory of Open Access Journals (Sweden)

Kèvin Knoops

2008-09-01

Full Text Available Positive-strand RNA viruses, a large group including human pathogens such as SARS-coronavirus (SARS-CoV, replicate in the cytoplasm of infected host cells. Their replication complexes are commonly associated with modified host cell membranes. Membrane structures supporting viral RNA synthesis range from distinct spherular membrane invaginations to more elaborate webs of packed membranes and vesicles. Generally, their ultrastructure, morphogenesis, and exact role in viral replication remain to be defined. Poorly characterized double-membrane vesicles (DMVs were previously implicated in SARS-CoV RNA synthesis. We have now applied electron tomography of cryofixed infected cells for the three-dimensional imaging of coronavirus-induced membrane alterations at high resolution. Our analysis defines a unique reticulovesicular network of modified endoplasmic reticulum that integrates convoluted membranes, numerous interconnected DMVs (diameter 200-300 nm, and "vesicle packets" apparently arising from DMV merger. The convoluted membranes were most abundantly immunolabeled for viral replicase subunits. However, double-stranded RNA, presumably revealing the site of viral RNA synthesis, mainly localized to the DMV interior. Since we could not discern a connection between DMV interior and cytosol, our analysis raises several questions about the mechanism of DMV formation and the actual site of SARS-CoV RNA synthesis. Our data document the extensive virus-induced reorganization of host cell membranes into a network that is used to organize viral replication and possibly hide replicating RNA from antiviral defense mechanisms. Together with biochemical studies of the viral enzyme complex, our ultrastructural description of this "replication network" will aid to further dissect the early stages of the coronavirus life cycle and its virus-host interactions.

How infectious is SARS virus

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. How infectious is SARS virus. Influenza: 1 patient infects ten people. SARS: 1 patient infects 2-4 people. Incubation period 10 days. Are there `silent´ cases ? Is quarantine enough ? How will it behave if and when it returns ?

Imaging in severe acute respiratory syndrome (SARS)

International Nuclear Information System (INIS)

Antonio, G.E.; Wong, K.T.; Chu, W.C.W.; Hui, D.S.C.; Cheng, F.W.T.; Yuen, E.H.Y.; Chung, S.S.C.; Fok, T.F.; Sung, J.J.Y.; Ahuja, A.T.

2003-01-01

Severe acute respiratory syndrome (SARS) is a highly infectious disease caused by a novel coronavirus, and has become pandemic within a short period of time. Imaging plays an important role in the diagnosis, management and follow-up of patients with SARS. The current status of imaging in SARS is presented in this review

Engaging nurse aide students to develop a survey to improve enrollment and retention in college.

Science.gov (United States)

Boyd, Jamie Kamailani; Hernandez, Jesika Y; Braun, Kathryn L

2011-01-01

Students from lower socioeconomic status (SES) backgrounds have historically experienced high rates of college dropout. Surveys often are used to assess supports and barriers (SB) to college enrollment and completion, and findings drive the design of interventions to improve student recruitment and retention. However, standard surveys may not include questions that solicit the breadth of issues facing low-income minority individuals. We used community-based participatory research (CBPR) principles to develop an SB survey to better reflect the concerns of rural, first-generation college students in Hawai'i. An advisory panel (AP) of students and community partners guided the work. The literature informed the first draft of the SB survey. Then we worked with students who had successfully completed a vocational Nurse Aide (NA) Training Program (NATP) course to refine four versions of the SB survey through multiple cycles of online survey review and focus groups. The final product included questions in new areas and differently phrased questions in standard areas (e.g., transportation, dependent care, housing, financial aid) to better capture reasons for students dropping out. The survey has proven useful as a student assessment tool, and findings are being used by instructors, counselors, and community partners to add resources and modify programs to increase student success in community college. Findings confirm the usefulness of engaging target partners in tool development. An enhanced understanding of SB of students from underrepresented groups will help to improve college recruitment and retention interventions.

Credit supply and the rise in college tuition: evidence from the expansion in federal student aid programs

OpenAIRE

Lucca, David O.; Nadauld, Taylor D.; Shen, Karen

2015-01-01

When students fund their education through loans, changes in student borrowing and tuition are interlinked. Higher tuition costs raise loan demand, but loan supply also affects equilibrium tuition costs - for example, by relaxing students' funding constraints. To resolve this simultaneity problem, we exploit detailed student-level financial data and changes in federal student aid programs to identify the impact of increased student loan funding on tuition. We find that institutions more expos...

PRF Ambiguity Detrmination for Radarsat ScanSAR System

Science.gov (United States)

Jin, Michael Y.

1998-01-01

PRF ambiguity is a potential problem for a spaceborne SAR operated at high frequencies. For a strip mode SAR, there were several approaches to solve this problem. This paper, however, addresses PRF ambiguity determination algorithms suitable for a burst mode SAR system such as the Radarsat ScanSAR. The candidate algorithms include the wavelength diversity algorithm, range look cross correlation algorithm, and multi-PRF algorithm.

Satellite on-board real-time SAR processor prototype

Science.gov (United States)

Bergeron, Alain; Doucet, Michel; Harnisch, Bernd; Suess, Martin; Marchese, Linda; Bourqui, Pascal; Desnoyers, Nicholas; Legros, Mathieu; Guillot, Ludovic; Mercier, Luc; Châteauneuf, François

2017-11-01

A Compact Real-Time Optronic SAR Processor has been successfully developed and tested up to a Technology Readiness Level of 4 (TRL4), the breadboard validation in a laboratory environment. SAR, or Synthetic Aperture Radar, is an active system allowing day and night imaging independent of the cloud coverage of the planet. The SAR raw data is a set of complex data for range and azimuth, which cannot be compressed. Specifically, for planetary missions and unmanned aerial vehicle (UAV) systems with limited communication data rates this is a clear disadvantage. SAR images are typically processed electronically applying dedicated Fourier transformations. This, however, can also be performed optically in real-time. Originally the first SAR images were optically processed. The optical Fourier processor architecture provides inherent parallel computing capabilities allowing real-time SAR data processing and thus the ability for compression and strongly reduced communication bandwidth requirements for the satellite. SAR signal return data are in general complex data. Both amplitude and phase must be combined optically in the SAR processor for each range and azimuth pixel. Amplitude and phase are generated by dedicated spatial light modulators and superimposed by an optical relay set-up. The spatial light modulators display the full complex raw data information over a two-dimensional format, one for the azimuth and one for the range. Since the entire signal history is displayed at once, the processor operates in parallel yielding real-time performances, i.e. without resulting bottleneck. Processing of both azimuth and range information is performed in a single pass. This paper focuses on the onboard capabilities of the compact optical SAR processor prototype that allows in-orbit processing of SAR images. Examples of processed ENVISAT ASAR images are presented. Various SAR processor parameters such as processing capabilities, image quality (point target analysis), weight and

What's wrong with John? a randomised controlled trial of Mental Health First Aid (MHFA) training with nursing students.

Science.gov (United States)

Burns, Sharyn; Crawford, Gemma; Hallett, Jonathan; Hunt, Kristen; Chih, Hui Jun; Tilley, P J Matt

2017-03-23

The prevalence of mental health problems have been found to be higher among university students compared to their non-student peers. Nursing students in particular face a range of additional stressors which may impact their undergraduate performance and their careers. Mental Health First Aid (MHFA) aims to increase mental health literacy and to reduce stigma and may positively impact on the student population. This paper describes a MHFA randomised controlled trial targeting nursing students at a large Australian university. This study aimed to measure the impact of the MHFA course on mental health literacy, mental health first aid intentions, confidence in helping someone with a mental health problem and stigmatising attitudes including social distance. Participants were first year nursing students (n = 181) randomly allocated to the intervention (n = 92) or control (n = 89) group. Intervention group participants received the standardised MHFA course for nursing students. Online self-report questionnaires were completed at three time intervals: baseline (one week prior to the intervention: T 1 ) (n = 140), post intervention (T 2 ) (n = 120), and two months post intervention (T 3 ) (n = 109). Measures included demographics, mental health knowledge, recognition of depression, confidence in helping, mental health first aid intentions and stigmatising attitudes including social distance. Repeated measures ANOVA was computed to measure if the impact of time (T 1 , T 2 , T 3 ) and group (intervention and control) on the outcome variables. There was a significant improvement among intervention compared to control group participants across the three time periods for knowledge scores (p mental health first aid intentions (p mental health literacy and reduce stigmatising attitudes and social distance. While this course has particular salience for nursing and other health science students, there are broader benefits to the general university population that

Institutional Planning: What Role for Directors of Student Admissions and Financial Aid?

Science.gov (United States)

Haines, John R.

1976-01-01

According to the director of Higher Education Management Services for the New York State Education Department, the offices of admissions and student financial aid have long been excluded from the institutional planning process. In an era of projected enrollment declines and increased competition, these offices need to assume a critical new role.…

First aid and basic life support training for first year medical students.

Science.gov (United States)

Altintaş, Kerim Hakan; Yildiz, Ali Naci; Aslan, Dilek; Ozvariş, Sevkat Bahar; Bilir, Nazmi

2009-12-01

We developed 24 and 12-h programs for first aid and basic life support (FA-BLS) training for first-year medical students and evaluated the opinions of both the trainers and trainees on the effectiveness of the programs. The trainees were the first-year students of academic years 2000-2001 (316 students) and 2001-2002 (366 students). The evaluations of the participants were collected from short questionnaires created specifically for the study. For the 24-h training program, most of the students stated that FA-BLS sessions met their expectations (85.9%) and they were satisfied with the training (91.1%). Of the participants, 75.6% stated that they could apply FA confidently in real situations simulating the topics they learned in the FA-BLS sessions. For the 12-h training program, 84.4% of the students felt themselves competent in FA-BLS applications. The trainers considered both of the programs as effective.

Monitoring Building Deformation with InSAR: Experiments and Validation

Science.gov (United States)

Yang, Kui; Yan, Li; Huang, Guoman; Chen, Chu; Wu, Zhengpeng

2016-01-01

Synthetic Aperture Radar Interferometry (InSAR) techniques are increasingly applied for monitoring land subsidence. The advantages of InSAR include high accuracy and the ability to cover large areas; nevertheless, research validating the use of InSAR on building deformation is limited. In this paper, we test the monitoring capability of the InSAR in experiments using two landmark buildings; the Bohai Building and the China Theater, located in Tianjin, China. They were selected as real examples to compare InSAR and leveling approaches for building deformation. Ten TerraSAR-X images spanning half a year were used in Permanent Scatterer InSAR processing. These extracted InSAR results were processed considering the diversity in both direction and spatial distribution, and were compared with true leveling values in both Ordinary Least Squares (OLS) regression and measurement of error analyses. The detailed experimental results for the Bohai Building and the China Theater showed a high correlation between InSAR results and the leveling values. At the same time, the two Root Mean Square Error (RMSE) indexes had values of approximately 1 mm. These analyses show that a millimeter level of accuracy can be achieved by means of InSAR technique when measuring building deformation. We discuss the differences in accuracy between OLS regression and measurement of error analyses, and compare the accuracy index of leveling in order to propose InSAR accuracy levels appropriate for monitoring buildings deformation. After assessing the advantages and limitations of InSAR techniques in monitoring buildings, further applications are evaluated. PMID:27999403

Monitoring Building Deformation with InSAR: Experiments and Validation

Directory of Open Access Journals (Sweden)

Kui Yang

2016-12-01

Full Text Available Synthetic Aperture Radar Interferometry (InSAR techniques are increasingly applied for monitoring land subsidence. The advantages of InSAR include high accuracy and the ability to cover large areas; nevertheless, research validating the use of InSAR on building deformation is limited. In this paper, we test the monitoring capability of the InSAR in experiments using two landmark buildings; the Bohai Building and the China Theater, located in Tianjin, China. They were selected as real examples to compare InSAR and leveling approaches for building deformation. Ten TerraSAR-X images spanning half a year were used in Permanent Scatterer InSAR processing. These extracted InSAR results were processed considering the diversity in both direction and spatial distribution, and were compared with true leveling values in both Ordinary Least Squares (OLS regression and measurement of error analyses. The detailed experimental results for the Bohai Building and the China Theater showed a high correlation between InSAR results and the leveling values. At the same time, the two Root Mean Square Error (RMSE indexes had values of approximately 1 mm. These analyses show that a millimeter level of accuracy can be achieved by means of InSAR technique when measuring building deformation. We discuss the differences in accuracy between OLS regression and measurement of error analyses, and compare the accuracy index of leveling in order to propose InSAR accuracy levels appropriate for monitoring buildings deformation. After assessing the advantages and limitations of InSAR techniques in monitoring buildings, further applications are evaluated.

A survey of a HBCU's senior year nursing students' perception of the HIV/AIDS phenomenon: a follow-up study.

Science.gov (United States)

Adepoju, Joseph A; Watkins, Mary P; Richardson, Agnes

2009-12-01

This study was a follow-up to a previous study that was done among first semester nursing college students at a historically Black college and university in northeastern United States. The original intent was to ascertain their perceptions and knowledge of various aspects of the Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) phenomenon. It involved an anonymous survey questionnaire featuring yes and no answers, a Likert scale, and qualitative response questions concerning prevention behavior. Respondents were asked whether HIV/AIDS could make an individual "sick enough to die", whether they thought that wearing a condom would diminish their feeling during the sexual experience, and whether they would insist their partners use a condom. The original study consisted of 68 students. The follow-up study,four years later, consisted of the 20 remaining nursing students from the original cohort and was undertaken with the intent to appraise their knowledge level and to ascertain whether their attitudes towards the use of condoms as a way to prevent HIV/AIDS and STDs had changed. Findings from this follow-up study indicated that educational attainment of the respondents did not translate into a change in attitudes about responsible sexual behavior. Further findings may suggest that intensive HIV/AIDS education begin at an earlier phase in a students'education. Along with the basics of HIV/AIDS education, students need to learn to be respectful of each others' health and wellbeing. It is essential that a nurturing and protective environment exist so that young women are not afraid of the consequences related to asking partners to wear condoms during sexual encounters.

Como Solicitar la Asistencia Economica Federal para Estudiantes (How To Apply for Federal Student Aid).

Science.gov (United States)

Office of Federal Student Aid (ED), Washington, DC.

This guide, written in Spanish, discusses reasons for going to college, how to pay for college, and how to apply for federal student aid in a series of brief, clear illustrations. Following outlines of financial benefits of college, college costs, and space to note costs for the student's area, the guide outlines these steps in the application…

A Self-Instructional Course in Student Financial Aid Administration. Module 14: Authorization, Fiscal Operations, & Reporting. Second Edition.

Science.gov (United States)

Washington Consulting Group, Inc., Washington, DC.

The 14th of 17 modules in a self-instructional course on student financial aid administration (geared toward novice financial aid administrators and other institutional personnel) focuses on Pell Grants and campus-based authorization, fiscal operations, and reporting. The full course provides an introduction to the management of federal financial…

Molecular mechanisms of severe acute respiratory syndrome (SARS

Directory of Open Access Journals (Sweden)

Zabel Peter

2005-01-01

Full Text Available Abstract Severe acute respiratory syndrome (SARS is a new infectious disease caused by a novel coronavirus that leads to deleterious pulmonary pathological features. Due to its high morbidity and mortality and widespread occurrence, SARS has evolved as an important respiratory disease which may be encountered everywhere in the world. The virus was identified as the causative agent of SARS due to the efforts of a WHO-led laboratory network. The potential mutability of the SARS-CoV genome may lead to new SARS outbreaks and several regions of the viral genomes open reading frames have been identified which may contribute to the severe virulence of the virus. With regard to the pathogenesis of SARS, several mechanisms involving both direct effects on target cells and indirect effects via the immune system may exist. Vaccination would offer the most attractive approach to prevent new epidemics of SARS, but the development of vaccines is difficult due to missing data on the role of immune system-virus interactions and the potential mutability of the virus. Even in a situation of no new infections, SARS remains a major health hazard, as new epidemics may arise. Therefore, further experimental and clinical research is required to control the disease.

Selection of SARS-Coronavirus-specific B cell epitopes by phage peptide library screening and evaluation of the immunological effect of epitope-based peptides on mice

International Nuclear Information System (INIS)

Yu Hua; Jiang Lifang; Fang Danyun; Yan Huijun; Zhou Jingjiao; Zhou Junmei; Liang Yu; Gao Yang; Zhao, Wei; Long Beiguo

2007-01-01

Antibodies to SARS-Coronavirus (SARS-CoV)-specific B cell epitopes might recognize the pathogen and interrupt its adherence to and penetration of host cells. Hence, these epitopes could be useful for diagnosis and as vaccine constituents. Using the phage-displayed peptide library screening method and purified Fab fragments of immunoglobulin G (IgG Fab) from normal human sera and convalescent sera from SARS-CoV-infected patients as targets, 11 B cell epitopes of SARS-CoV spike glycoprotein (S protein) and membrane protein (M protein) were screened. After a bioinformatics tool was used to analyze these epitopes, four epitope-based S protein dodecapeptides corresponding to the predominant epitopes were chosen for synthesis. Their antigenic specificities and immunogenicities were studied in vitro and in vivo. Flow cytometry and ELISPOT analysis of lymphocytes as well as a serologic analysis of antibody showed that these peptides could trigger a rapid, highly effective, and relatively safe immune response in BALB/c mice. These findings might aid development of SARS diagnostics and vaccines. Moreover, the role of S and M proteins as important surface antigens is confirmed

Attitudes of health care students about computer-aided neuroanatomy instruction.

Science.gov (United States)

McKeough, D Michael; Bagatell, Nancy

2009-01-01

This study examined students' attitudes toward computer-aided instruction (CAI), specifically neuroanatomy learning modules, to assess which components were primary in establishing these attitudes and to discuss the implications of these attitudes for successfully incorporating CAI in the preparation of health care providers. Seventy-seven masters degree, entry-level, health care professional students matriculated in an introductory neuroanatomy course volunteered as subjects for this study. Students independently reviewed the modules as supplements to lecture and completed a survey to evaluate teaching effectiveness. Responses to survey statements were compared across the learning modules to determine if students viewed the modules differently. Responses to individual survey statements were averaged to measure the strength of agreement or disagreement with the statement. Responses to open-ended questions were theme coded, and frequencies and percentages were calculated for each. Students saw no differences between the learning modules. Students perceived the learning modules as valuable; they enjoyed using the modules but did not prefer CAI over traditional lecture format. The modules were useful in learning or reinforcing neuroanatomical concepts and improving clinical problem-solving skills. Students reported that the visual representation of the neuroanatomical systems, computer animation, ability to control the use of the modules, and navigational fidelity were key factors in determining attitudes. The computer-based learning modules examined in this study were effective as adjuncts to lecture in helping entry-level health care students learn and make clinical applications of neuroanatomy information.

Spatial distribution of infection risk of SARS transmission in a hospital ward

Energy Technology Data Exchange (ETDEWEB)

Qian, Hua; Li, Yuguo [School of Energy and Environment, Southeast University, Nanjing, JiangSu (China); Nielsen, Peter V. [Department of Civil Engineering, Aalborg University, DK-9000 Aalborg (Denmark); Huang, Xinhua [Institute of Refrigeration and Cryogenics Engineering, Shanghai Jiaotong University, Shanghai (China)

2009-08-15

The classical Wells-Riley model for predicting risk of airborne transmission of diseases assumes a uniform spatial distribution of the infected cases in an enclosed space. A new mathematical model is developed here for predicting the spatial distribution of infection risk of airborne transmitted diseases by integrating the Wells-Riley equation into computational fluid dynamics. We applied our new integrated model to analyze a large nosocomial SARS outbreak in Hong Kong during the 2003 SARS epidemics, which was studied in the literature with regard to the association between airflow and SARS infection. The predicted numbers of infected cases of medical students in the same cubicle, the adjacent cubicle and the distant cubicle were 6.39, 0.78 and 0.2 respectively while the observed numbers of infected medical students in the three cubicles were 7, 0 and 0 respectively during the morning of March 6th, which was the highest attack period. The predicted numbers of infected cases of inpatients during the morning of March 6th in the same cubicle, the adjacent cubic and the distance cubicle were 7.8, 5.1, and 4.8 respectively which also agree well with the observed distribution of the infected inpatients during the entire infection period. The new developed model provides a new modelling tool for investigating the airborne transmission of diseases in enclosed spaces. The model is applicable when the susceptible stays mostly at the same location in an enclosed space during the infectious period, such as inpatients in a hospital ward, passengers in an airplane etc. (author)

Conception of undergraduate nursing students on the practice of health education on first aid

OpenAIRE

Marília Rosa de Oliveira; Ana Rita Arrigo Leonel; Juliana Helena Montezeli; Andréia Bendine Gastaldi; Eleine Aparecida Penha Martins; Cristiano Caveião

2015-01-01

Objective: to present the conception of undergraduate nursing students participating in an integrated project on health education on first aid. Methods: qualitative research conducted at the Universidade Estadual de Londrina with five senior nursing students, participating in the project “Nursing in clinical and surgical urgent and emergency care.” We applied semi-structured interviews with content analysis. Results: the following categories emerged: Health education as a facilitator for acad...

Do Visual Aids Really Matter?

Directory of Open Access Journals (Sweden)

Kristine Fish

2016-01-01

Full Text Available Educational webcasts or video lectures as a teaching tool and a form of visual aid have become widely used with the rising prevalence of online and blended courses and with the increase of web-based video materials. Thus, research pertaining to factors enhancing the effectiveness of video lectures, such as number of visual aids, is critical. This study compared student evaluations before and after embedding additional visual aids throughout video lectures in an online course. Slide transitions occurred on average every 40 seconds for the pre-treatment group with approximately 600 visuals total, compared to slide transitions every 10 seconds for the post-treatment group with approximately 2,000 visuals total. All students received the same audio recordings. Research questions addressed are: (1 Are student perceptions of the effectiveness of examples used to illustrate concepts affected by number of visual aids? (2 Is the extent to which students feel engaged during the lectures affected by number of visual aids? (3 Are students’ perceived overall learning experiences affected by number of visual aids? Surprisingly, results indicate that for questions #1 and #3, student ratings of those who viewed videos with fewer visuals rated their experiences higher than students who viewed more visuals. There was no significant difference found for question #2. Conclusion: Although some visuals have been shown to enhance learning, too many visuals may be a deterrent to learning.

Unsupervised SBAS-DInSAR Processing of Space-borne SAR data for Earth Surface Displacement Time Series Generation

Science.gov (United States)

Casu, F.; de Luca, C.; Lanari, R.; Manunta, M.; Zinno, I.

2016-12-01

During the last 25 years, the Differential Synthetic Aperture Radar Interferometry (DInSAR) has played an important role for understanding the Earth's surface deformation and its dynamics. In particular, the large collections of SAR data acquired by a number of space-borne missions (ERS, ENVISAT, ALOS, RADARSAT, TerraSAR-X, COSMO-SkyMed) have pushed toward the development of advanced DInSAR techniques for monitoring the temporal evolution of the ground displacements with an high spatial density. Moreover, the advent of the Copernicus Sentinel-1 (S1) constellation is providing a further increase in the SAR data flow available to the Earth science community, due to its characteristics of global coverage strategy and free and open access data policy. Therefore, managing and storing such a huge amount of data, processing it in an effcient way and maximizing the available archives exploitation are becoming high priority issues. In this work we present some recent advances in the DInSAR field for dealing with the effective exploitation of the present and future SAR data archives. In particular, an efficient parallel SBAS implementation (namely P-SBAS) that takes benefit from high performance computing is proposed. Then, the P-SBAS migration to the emerging Cloud Computing paradigm is shown, together with extensive tests carried out in the Amazon's Elastic Cloud Compute (EC2) infrastructure. Finally, the integration of the P-SBAS processing chain within the ESA Geohazards Exploitation Platform (GEP), for setting up operational on-demand and systematic web tools, open to every user, aimed at automatically processing stacks of SAR data for the generation of SBAS displacement time series, is also illustrated. A number of experimental results obtained by using the ERS, ENVISAT and S1 data in areas characterized by volcanic, seismic and anthropogenic phenomena will be shown. This work is partially supported by: the DPC-CNR agreement, the EPOS-IP project and the ESA GEP project.

Paying for Default: Change over Time in the Share of Federal Financial Aid Sent to Institutions with High Student Loan Default Rates

Science.gov (United States)

Jaquette, Ozan; Hillman, Nicholas W.

2015-01-01

Both federal spending on financial aid and student loan default rates have increased over the past decade. These trends have intensified policymakers' concerns that some postsecondary institutions-- particularly in the for-profit sector--maximize revenue derived from federal financial aid without helping students to graduate or find employment.…

Dynamic changes of serum SARS-Coronavirus IgG, pulmonary function and radiography in patients recovering from SARS after hospital discharge

Directory of Open Access Journals (Sweden)

Chen Liangan

2005-01-01

Full Text Available Abstract Objective The intent of this study was to examine the recovery of individuals who had been hospitalized for severe acute respiratory syndrome (SARS in the year following their discharge from the hospital. Parameters studied included serum levels of SARS coronavirus (SARS-CoV IgG antibody, tests of lung function, and imaging data to evaluate changes in lung fibrosis. In addition, we explored the incidence of femoral head necrosis in some of the individuals recovering from SARS. Methods The subjects of this study were 383 clinically diagnosed SARS patients in Beijing, China. They were tested regularly for serum levels of SARS-CoV IgG antibody and lung function and were given chest X-rays and/or high resolution computerized tomography (HRCT examinations at the Chinese PLA General Hospital during the 12 months that followed their release from the hospital. Those individuals who were found to have lung diffusion abnormities (transfer coefficient for carbon monoxide [DLCO] Findings Of all the subjects, 81.2% (311 of 383 patients tested positive for serum SARS-CoV IgG. Of those testing positive, 27.3% (85 of 311 patients were suffering from lung diffusion abnormities (DLCO Interpretation The lack of sero-positive SARS-CoV in some individuals suggests that there may have been some misdiagnosed cases among the subjects included in this study. Of those testing positive, the serum levels of SARS-CoV IgG antibody decreased significantly during the 12 months after hospital discharge. Additionally, we found that the individuals who had lung fibrosis showed some spontaneous recovery. Finally, some of the subjects developed femoral head necrosis.

Nano(Q)SAR: Challenges, pitfalls and perspectives.

Science.gov (United States)

Tantra, Ratna; Oksel, Ceyda; Puzyn, Tomasz; Wang, Jian; Robinson, Kenneth N; Wang, Xue Z; Ma, Cai Y; Wilkins, Terry

2015-01-01

Regulation for nanomaterials is urgently needed, and the drive to adopt an intelligent testing strategy is evident. Such a strategy will not only provide economic benefits but will also reduce moral and ethical concerns arising from animal testing. For regulatory purposes, such an approach is promoted by REACH, particularly the use of quantitative structure-activity relationships [(Q)SAR] as a tool for the categorisation of compounds according to their physicochemical and toxicological properties. In addition to compounds, (Q)SAR has also been applied to nanomaterials in the form of nano(Q)SAR. Although (Q)SAR in chemicals is well established, nano(Q)SAR is still in early stages of development and its successful uptake is far from reality. This article aims to identify some of the pitfalls and challenges associated with nano-(Q)SARs in relation to the categorisation of nanomaterials. Our findings show clear gaps in the research framework that must be addressed if we are to have reliable predictions from such models. Three major barriers were identified: the need to improve quality of experimental data in which the models are developed from, the need to have practical guidelines for the development of the nano(Q)SAR models and the need to standardise and harmonise activities for the purpose of regulation. Of these three, the first, i.e. the need to improve data quality requires immediate attention, as it underpins activities associated with the latter two. It should be noted that the usefulness of data in the context of nano-(Q)SAR modelling is not only about the quantity of data but also about the quality, consistency and accessibility of those data.

CONTEMPORARY TEACHING AIDS IN TEACHING MATHEMATICS

OpenAIRE

Sead Rešić; Eldina Atić

2014-01-01

In this research, the application of contemporary teaching aids in Mathematics teaching in elementary school was analyzed from the aspect of teachers, students and parents. The application of contemporary teaching aids in Mathematics teaching was analyzed through a sample of 100 students, and attitudes about the aids were examined from the points of view of students, teachers and parents. In this research, descriptive method, questionnaire and test were used. Results of the resear...

Playback system designed for X-Band SAR

International Nuclear Information System (INIS)

Yuquan, Liu; Changyong, Dou

2014-01-01

SAR(Synthetic Aperture Radar) has extensive application because it is daylight and weather independent. In particular, X-Band SAR strip map, designed by Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, provides high ground resolution images, at the same time it has a large spatial coverage and a short acquisition time, so it is promising in multi-applications. When sudden disaster comes, the emergency situation acquires radar signal data and image as soon as possible, in order to take action to reduce loss and save lives in the first time. This paper summarizes a type of X-Band SAR playback processing system designed for disaster response and scientific needs. It describes SAR data workflow includes the payload data transmission and reception process. Playback processing system completes signal analysis on the original data, providing SAR level 0 products and quick image. Gigabit network promises radar signal transmission efficiency from recorder to calculation unit. Multi-thread parallel computing and ping pong operation can ensure computation speed. Through gigabit network, multi-thread parallel computing and ping pong operation, high speed data transmission and processing meet the SAR radar data playback real time requirement

Playback system designed for X-Band SAR

Science.gov (United States)

Yuquan, Liu; Changyong, Dou

2014-03-01

SAR(Synthetic Aperture Radar) has extensive application because it is daylight and weather independent. In particular, X-Band SAR strip map, designed by Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, provides high ground resolution images, at the same time it has a large spatial coverage and a short acquisition time, so it is promising in multi-applications. When sudden disaster comes, the emergency situation acquires radar signal data and image as soon as possible, in order to take action to reduce loss and save lives in the first time. This paper summarizes a type of X-Band SAR playback processing system designed for disaster response and scientific needs. It describes SAR data workflow includes the payload data transmission and reception process. Playback processing system completes signal analysis on the original data, providing SAR level 0 products and quick image. Gigabit network promises radar signal transmission efficiency from recorder to calculation unit. Multi-thread parallel computing and ping pong operation can ensure computation speed. Through gigabit network, multi-thread parallel computing and ping pong operation, high speed data transmission and processing meet the SAR radar data playback real time requirement.

Retention of first aid and basic life support skills in undergraduate medical students

NARCIS (Netherlands)

Ruijter, P.A. de; Biersteker, H.A.; Biert, J.; Goor, H. van; Tan, E.C.T.H.

2014-01-01

BACKGROUND: Undergraduate medical students follow a compulsory first aid (FA) and basic life support (BLS) course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in

Wave directional spectrum from SAR imagery

Digital Repository Service at National Institute of Oceanography (India)

Fernandes, A.A.; Sarma, Y.V.B.; Menon, H.B.; Vethamony, P.

< 2m and the zero-crossing period during the satellite overpass is small (< 6s, �O�O < 60m). We therefore utilized the visit of one of the authors (Sarma) to the Southampton Oceanographic Centre, U.K., to procure two ERS-1 digital image mode SAR...-dimensional FFT as well as a computer program for downloading SAR data from CCT. Finally we owe a debt of gratitude to J C da Silva, Southampton Oceanographic Centre, U K for sharing some of his SAR data with us. References Allan T. D. (Ed) (1983...

Student Credit Card Debt in the 21st Century: Options for Financial Aid Administrators.

Science.gov (United States)

Oleson, Mark

2001-01-01

Provides multiple workable solutions financial aid offices can offer students throughout their college experience to deal with debt: preventive solutions for avoiding problems with credit card debt, holistic solutions for other related problems, and remedial solutions for existing problems. (EV)

Wave directional spectrum from SAR imagery

Digital Repository Service at National Institute of Oceanography (India)

Fernandes, A.A.; Sarma, Y.V.B.; Menon, H.B.; Vethamony, P.

Gaussian smoothed SAR image spectra have been evaluated from 512 x 512 pixel subscenes of image mode ERS-1 SAR scenes off Goa, Visakhapatnam, Paradeep and Portugal. The two recently acquired scenes off Portugal showed the signature of swell...

The perception amongst a population of high school students in South Africa about ocular manifestations of HIV/AIDS*

Directory of Open Access Journals (Sweden)

I. T. Melwa

2012-12-01

Full Text Available HIV and AIDS can result in visual impairment, therefore it is important that those who have or atrisk of contracting the disease have a basic knowledge of its ocular manifestations, so that they may seek eye care early. This study assessed the per-ceptions of a sample of senior high school students at the Capricorn district, Limpopo Province, South Africa about the ocular manifestations of HIV/AIDS and its management. Questionnaires were distributed to the students in their classrooms after school hours and upon completion were collected the same day. Data analysis revealed that 27.8% of the participants agreed that HIV/AIDS can affect the eyes. Another 27.8% responded that HIV/AIDS could cause dry eyes. Less than a third (31.4% indicated that the disease could cause red eyes, 31.5% and 38.1% respectively indicated that HIV/AIDS could cause cancer of the eyelids and the eyeball.  About half of the respondents (52% agreed that the disease could cause swollen eyelids; while about 46% agreed that vision loss or blindness could occur in HIV/AIDS.  Many (65.6% indicated that an ophthalmologist or an optometrist should be consulted for HIV/AIDS-related eye problems and only 16.5% reported that traditional healers could be consulted. Perception about the ocular manifestations of HIV and AIDS is poor among the participants, suggesting a need for awareness campaigns and education.  (S Afr Optom 2012 71(3 117-122

Image based SAR product simulation for analysis

Science.gov (United States)

Domik, G.; Leberl, F.

1987-01-01

SAR product simulation serves to predict SAR image gray values for various flight paths. Input typically consists of a digital elevation model and backscatter curves. A new method is described of product simulation that employs also a real SAR input image for image simulation. This can be denoted as 'image-based simulation'. Different methods to perform this SAR prediction are presented and advantages and disadvantages discussed. Ascending and descending orbit images from NASA's SIR-B experiment were used for verification of the concept: input images from ascending orbits were converted into images from a descending orbit; the results are compared to the available real imagery to verify that the prediction technique produces meaningful image data.

Improvements of knowledge and perception towards HIV/AIDS among secondary school students after two hours talk.

Science.gov (United States)

Jahanfar, S; Lim, A W; Loh, M A; Yeoh, A G; Charles, A

2008-10-01

Malaysia is confronted with an increasing incidence of HIV and AIDS among adolescents and young adults. The effectiveness of various programs offered to school going teenagers is unknown. The objective of this study is to measure the effectiveness of two hours talk on sex education offered by a non governmental organization (NGO) in improving youngsters' knowledge and perception towards HIV and AIDS. A cross sectional study was conducted among the adolescent students from a secondary school in Ipoh, Perak, a province of Malaysia. A total of 182 students participated in the study. A standard questionnaire consisting of demographic data, knowledge and perception towards HIV/ADIS were distributed before (pre-test) and after the intervention (post-test). Performance of participants was compared to establish the effectiveness of the intervention. Our findings suggests that there was a significant increase in participants' knowledge and perception after the intervention (p = 0.000). Knowledge improvement was found in both genders however, improvement in perception was higher among female students. Interestingly, 80% of participants disagree that sexual education will encourage sex among youngsters. NGOs are playing a supplementary role in providing sex education programs in schools. This program although of short duration but it is effective in enhancing adolescence awareness about HIV/AIDS.

FROM THE EXPERIENCES OF TEACHING AIDS «PHYSICS IN SPORTS» FOR STUDENT-ATHLETES

Directory of Open Access Journals (Sweden)

A. R. Kamаleyeva

2014-10-01

Full Text Available A small number of audience hours (6 hours of lectures and 10 hours of practical training, provided for the study of the discipline «Natural scientific basics of physical culture and sports: Physics» student-athletes who are forced not to attend classes because of their participation in sports events and competitions, is not always enough for a complete mastery of their respective standard competencies.The way out of this situation may be the use of new methodological approaches, remote technologies, innovative teaching tools such as, for example, «Physics in sport» - designed by us as teaching methodical aid. The formulation of this allowance based on the idea of modular integration, the activity, the competency, concentrated, historical, personal and multi-dimensional approaches. As a result, the precise structure of the textbook, each topic which includes specific components (problem, unit upgrades, historical block, the theoretical block, generalization and systematization, block expansion and deepening, block of individual works, literature, allows student-athletes to study the laws physics in relation to the sport that allows you to use and transform the physical culture of the laws of natural science disciplines.The teaching methodical aid can be used with success for students of other directions, for example, «Adaptive physical education».

Reverse genetics of SARS-related coronavirus using vaccinia virus-based recombination.

Directory of Open Access Journals (Sweden)

Sjoerd H E van den Worm

Full Text Available Severe acute respiratory syndrome (SARS is a zoonotic disease caused by SARS-related coronavirus (SARS-CoV that emerged in 2002 to become a global health concern. Although the original outbreak was controlled by classical public health measures, there is a real risk that another SARS-CoV could re-emerge from its natural reservoir, either in its original form or as a more virulent or pathogenic strain; in which case, the virus would be difficult to control in the absence of any effective antiviral drugs or vaccines. Using the well-studied SARS-CoV isolate HKU-39849, we developed a vaccinia virus-based SARS-CoV reverse genetic system that is both robust and biosafe. The SARS-CoV genome was cloned in separate vaccinia virus vectors, (vSARS-CoV-5prime and vSARS-CoV-3prime as two cDNAs that were subsequently ligated to create a genome-length SARS-CoV cDNA template for in vitro transcription of SARS-CoV infectious RNA transcripts. Transfection of the RNA transcripts into permissive cells led to the recovery of infectious virus (recSARS-CoV. Characterization of the plaques produced by recSARS-CoV showed that they were similar in size to the parental SARS-CoV isolate HKU-39849 but smaller than the SARS-CoV isolate Frankfurt-1. Comparative analysis of replication kinetics showed that the kinetics of recSARS-CoV replication are similar to those of SARS-CoV Frankfurt-1, although the titers of virus released into the culture supernatant are approximately 10-fold less. The reverse genetic system was finally used to generate a recSARS-CoV reporter virus expressing Renilla luciferase in order to facilitate the analysis of SARS-CoV gene expression in human dendritic cells (hDCs. In parallel, a Renilla luciferase gene was also inserted into the genome of human coronavirus 229E (HCoV-229E. Using this approach, we demonstrate that, in contrast to HCoV-229E, SARS-CoV is not able to mediate efficient heterologous gene expression in hDCs.

Spaceborne Differential SAR Interferometry: Data Analysis Tools for Deformation Measurement

Directory of Open Access Journals (Sweden)

Michele Crosetto

2011-02-01

Full Text Available This paper is focused on spaceborne Differential Interferometric SAR (DInSAR for land deformation measurement and monitoring. In the last two decades several DInSAR data analysis procedures have been proposed. The objective of this paper is to describe the DInSAR data processing and analysis tools developed at the Institute of Geomatics in almost ten years of research activities. Four main DInSAR analysis procedures are described, which range from the standard DInSAR analysis based on a single interferogram to more advanced Persistent Scatterer Interferometry (PSI approaches. These different procedures guarantee a sufficient flexibility in DInSAR data processing. In order to provide a technical insight into these analysis procedures, a whole section discusses their main data processing and analysis steps, especially those needed in PSI analyses. A specific section is devoted to the core of our PSI analysis tools: the so-called 2+1D phase unwrapping procedure, which couples a 2D phase unwrapping, performed interferogram-wise, with a kind of 1D phase unwrapping along time, performed pixel-wise. In the last part of the paper, some examples of DInSAR results are discussed, which were derived by standard DInSAR or PSI analyses. Most of these results were derived from X-band SAR data coming from the TerraSAR-X and CosmoSkyMed sensors.

Growing of the mathematical thinking imaginative to students in designing of the teaching aids for CWD towards to joyful learning

Science.gov (United States)

Sugiman; Sugiharti, E.; Kurniawati, N. F.

2018-03-01

Government and the private parties had also organized of Special School (SS) and Inclusive School. SS requires of math teachers who were professional in the material, but also master the needs of Children with Disabilities (CwD) in teaching-learning process. The problem: How to design the Teaching Aids for CwD through Extra-Curriculum Training (ECT) activities to Joyful Learning? The purposes of this research: (1) To find new ways how to grow the imaginative in mathematical thinking for students of Mathematics Education. (2) To find a Teaching Aids Design that suitable for CwD who studying in SS. (3) In order to create a Teaching Aids for CwD through activities based on ECT to Joyful Learning. The research method was done by qualitative approach. The research subjects were 6 students of Mathematics Education Study Program of FMIPA UNNES who were interested in attending of the training activities based on ECT. The results: (1) ECT can be a place to grow an Imaginative in Mathematical Thinking of students, (2) created the design of the teaching aids for CwD through activities based on ECT to Joyful Learning as a mirror of the imaginative growth in mathematical thinking for students.

An Adaptive Ship Detection Scheme for Spaceborne SAR Imagery

Directory of Open Access Journals (Sweden)

Xiangguang Leng

2016-08-01

Full Text Available With the rapid development of spaceborne synthetic aperture radar (SAR and the increasing need of ship detection, research on adaptive ship detection in spaceborne SAR imagery is of great importance. Focusing on practical problems of ship detection, this paper presents a highly adaptive ship detection scheme for spaceborne SAR imagery. It is able to process a wide range of sensors, imaging modes and resolutions. Two main stages are identified in this paper, namely: ship candidate detection and ship discrimination. Firstly, this paper proposes an adaptive land masking method using ship size and pixel size. Secondly, taking into account the imaging mode, incidence angle, and polarization channel of SAR imagery, it implements adaptive ship candidate detection in spaceborne SAR imagery by applying different strategies to different resolution SAR images. Finally, aiming at different types of typical false alarms, this paper proposes a comprehensive ship discrimination method in spaceborne SAR imagery based on confidence level and complexity analysis. Experimental results based on RADARSAT-1, RADARSAT-2, TerraSAR-X, RS-1, and RS-3 images demonstrate that the adaptive scheme proposed in this paper is able to detect ship targets in a fast, efficient and robust way.

Pyrimidine and nucleoside gamma-esters of L-Glu-Sar

DEFF Research Database (Denmark)

Eriksson, André H; Elm, Peter L; Begtrup, Mikael

2005-01-01

-tetrahydrofuran-3-yl ester)-Sar (I), l-Glu(thymine-1-yl-methyl ester)-Sar (II) and l-Glu(acyclothymidine)-Sar (III) were synthesised and in vitro stability was studied in various aqueous and biological media. Affinity to and translocation via hPEPT1 was investigated in mature Caco-2 cell monolayers, grown......The aim of the present study was to improve the synthetic pathway of bioreversible dipeptide derivatives as well as evaluate the potential of using l-Glu-Sar as a pro-moiety for delivering three newly synthesised nucleoside and pyrimidine l-Glu-Sar derivatives. l-Glu(trans-2-thymine-1-yl...

Use of SAR data for proliferation monitoring

International Nuclear Information System (INIS)

Lafitte, M.; Robin, J.P.

2013-01-01

Synthetic Aperture Radar (SAR) is an active and coherent system. SAR images are complex data which contain both amplitude and phase information. The analysis of single SAR data required a very good experience and a good understanding of SAR geometry regarding layover, shadowing, texture and speckle. Image analyst can depicts and describes most of the facilities related to nuclear proliferation and weapons of mass destruction (WMD). The Amplitude Change Detection (ACD) technique consists of a combination of two or three SAR amplitude data acquired with similar orbit and frequency parameters on different dates. That technique provides a very good overview of the changes and particularly regarding vehicles activity and constructions ongoing within the area of interest over the monitoring period. One of the particularities of the SAR systems is to be coherent. The phase of a single image is not exploitable. Thus when two or more SAR data have been acquired with identical orbit and frequency parameters, the phases shift are indicators of changes such as structural changes, terrain subsidence or motion. The Multi-Temporal Coherence (MTC) product merged the two type of information previously detailed: the ACD and coherence analysis. It consists of the combination of two amplitude images and the corresponding coherence computed image. The MTC image may highlights changes between two states of a target which on the ACD analysis appeared unchanged. EUSC uses the difference interferometry techniques in order to estimate volumes that have changed between two acquisition dates. The paper is followed by the slides of the presentation. (A.C.)

SAR and LIDAR fusion: experiments and applications

Science.gov (United States)

Edwards, Matthew C.; Zaugg, Evan C.; Bradley, Joshua P.; Bowden, Ryan D.

2013-05-01

In recent years ARTEMIS, Inc. has developed a series of compact, versatile Synthetic Aperture Radar (SAR) systems which have been operated on a variety of small manned and unmanned aircraft. The multi-frequency-band SlimSAR has demonstrated a variety of capabilities including maritime and littoral target detection, ground moving target indication, polarimetry, interferometry, change detection, and foliage penetration. ARTEMIS also continues to build upon the radar's capabilities through fusion with other sensors, such as electro-optical and infrared camera gimbals and light detection and ranging (LIDAR) devices. In this paper we focus on experiments and applications employing SAR and LIDAR fusion. LIDAR is similar to radar in that it transmits a signal which, after being reflected or scattered by a target area, is recorded by the sensor. The differences are that a LIDAR uses a laser as a transmitter and optical sensors as a receiver, and the wavelengths used exhibit a very different scattering phenomenology than the microwaves used in radar, making SAR and LIDAR good complementary technologies. LIDAR is used in many applications including agriculture, archeology, geo-science, and surveying. Some typical data products include digital elevation maps of a target area and features and shapes extracted from the data. A set of experiments conducted to demonstrate the fusion of SAR and LIDAR data include a LIDAR DEM used in accurately processing the SAR data of a high relief area (mountainous, urban). Also, feature extraction is used in improving geolocation accuracy of the SAR and LIDAR data.

A Snapshot: South African University Students' Attitudes, Perceptions and Knowledge of HIV/AIDS

Science.gov (United States)

Raijmakers, L. R.; Pretorius, J. D.

2006-01-01

This article presents the findings of a survey conducted in August 2004 of students' attitudes, perceptions and knowledge about sexually transmitted infections, HIV/AIDS and sexual practices at an Institution of Higher Education. The study was set against the backdrop of the 2004 South African national survey, conducted by the Reproductive Health…

Undergraduates with Employer-Sponsored Aid: Comparing Group Differences

Science.gov (United States)

Faulk, Dagney G.; Wang, Zhenlei

2014-01-01

Tuition assistance offered by employers is an understudied area of financial aid research. The purpose of this study is to compare the demographic, socioeconomic, academic and financial aid characteristics of college students who receive employer-sponsored financial aid with students who receive traditional financial aid (institutional, state, or…

Polarimetric SAR interferometry-based decomposition modelling for reliable scattering retrieval

Science.gov (United States)

Agrawal, Neeraj; Kumar, Shashi; Tolpekin, Valentyn

2016-05-01

Fully Polarimetric SAR (PolSAR) data is used for scattering information retrieval from single SAR resolution cell. Single SAR resolution cell may contain contribution from more than one scattering objects. Hence, single or dual polarized data does not provide all the possible scattering information. So, to overcome this problem fully Polarimetric data is used. It was observed in previous study that fully Polarimetric data of different dates provide different scattering values for same object and coefficient of determination obtained from linear regression between volume scattering and aboveground biomass (AGB) shows different values for the SAR dataset of different dates. Scattering values are important input elements for modelling of forest aboveground biomass. In this research work an approach is proposed to get reliable scattering from interferometric pair of fully Polarimetric RADARSAT-2 data. The field survey for data collection was carried out for Barkot forest during November 10th to December 5th, 2014. Stratified random sampling was used to collect field data for circumference at breast height (CBH) and tree height measurement. Field-measured AGB was compared with the volume scattering elements obtained from decomposition modelling of individual PolSAR images and PolInSAR coherency matrix. Yamaguchi 4-component decomposition was implemented to retrieve scattering elements from SAR data. PolInSAR based decomposition was the great challenge in this work and it was implemented with certain assumptions to create Hermitian coherency matrix with co-registered polarimetric interferometric pair of SAR data. Regression analysis between field-measured AGB and volume scattering element obtained from PolInSAR data showed highest (0.589) coefficient of determination. The same regression with volume scattering elements of individual SAR images showed 0.49 and 0.50 coefficients of determination for master and slave images respectively. This study recommends use of

Federated query services provided by the Seamless SAR Archive project

Science.gov (United States)

Baker, S.; Bryson, G.; Buechler, B.; Meertens, C. M.; Crosby, C. J.; Fielding, E. J.; Nicoll, J.; Youn, C.; Baru, C.

2013-12-01

The NASA Advancing Collaborative Connections for Earth System Science (ACCESS) seamless synthetic aperture radar (SAR) archive (SSARA) project is a 2-year collaboration between UNAVCO, the Alaska Satellite Facility (ASF), the Jet Propulsion Laboratory (JPL), and OpenTopography at the San Diego Supercomputer Center (SDSC) to design and implement a seamless distributed access system for SAR data and derived data products (i.e. interferograms). A major milestone for the first year of the SSARA project was a unified application programming interface (API) for SAR data search and results at ASF and UNAVCO (WInSAR and EarthScope data archives) through the use of simple web services. A federated query service was developed using the unified APIs, providing users a single search interface for both archives (http://www.unavco.org/ws/brokered/ssara/sar/search). A command line client that utilizes this new service is provided as an open source utility for the community on GitHub (https://github.com/bakerunavco/SSARA). Further API development and enhancements added more InSAR specific keywords and quality control parameters (Doppler centroid, faraday rotation, InSAR stack size, and perpendicular baselines). To facilitate InSAR processing, the federated query service incorporated URLs for DEM (from OpenTopography) and tropospheric corrections (from the JPL OSCAR service) in addition to the URLs for SAR data. This federated query service will provide relevant QC metadata for selecting pairs of SAR data for InSAR processing and all the URLs necessary for interferogram generation. Interest from the international community has prompted an effort to incorporate other SAR data archives (the ESA Virtual Archive 4 and the DLR TerraSAR-X_SSC Geohazard Supersites and Natural Laboratories collections) into the federated query service which provide data for researchers outside the US and North America.

SARS – Koch´Postulates proved.

Indian Academy of Sciences (India)

SARS – Koch´Postulates proved. Novel coronavirus identified from fluids of patients. Virus cultured in Vero cell line. Sera of patients have antibodies to virus. Cultured virus produces disease in Macaque monkeys. -produces specific immune response; -isolated virus is SARS CoV; -pathology similar to human.

Attribute Learning for SAR Image Classification

Directory of Open Access Journals (Sweden)

Chu He

2017-04-01

Full Text Available This paper presents a classification approach based on attribute learning for high spatial resolution Synthetic Aperture Radar (SAR images. To explore the representative and discriminative attributes of SAR images, first, an iterative unsupervised algorithm is designed to cluster in the low-level feature space, where the maximum edge response and the ratio of mean-to-variance are included; a cross-validation step is applied to prevent overfitting. Second, the most discriminative clustering centers are sorted out to construct an attribute dictionary. By resorting to the attribute dictionary, a representation vector describing certain categories in the SAR image can be generated, which in turn is used to perform the classifying task. The experiments conducted on TerraSAR-X images indicate that those learned attributes have strong visual semantics, which are characterized by bright and dark spots, stripes, or their combinations. The classification method based on these learned attributes achieves better results.

SAR system development for UAV multicopter platforms

OpenAIRE

Escartin Martínez, Antonio

2015-01-01

SAR system development for UAV multicopter platforms This thesis describes the optimization of a synthetic aperture radar (SAR) at X-band and its integration into an unmanned aerial vehicle (UAV) of type octocopter. For such optimization the SAR system functionality was extended from singlepol to fulpol and it has been optimized at hardware level in order to improve its quality against noise figure. After its integration into the octocopter platform, its features has been used in order to ...

Novel Polarimetric SAR Interferometry Algorithms, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Polarimetric radar interferometry (PolInSAR) is a new SAR imaging mode that is rapidly becoming an important technique for bare earth topographic mapping, tree...

Broadening of neutralization activity to directly block a dominant antibody-driven SARS-coronavirus evolution pathway.

Directory of Open Access Journals (Sweden)

Jianhua Sui

2008-11-01

Full Text Available Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S protein of animal and human SARS coronaviruses (SARS-CoVs during and between two zoonotic transfers (2002/03 and 2003/04 are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID "hot spot" in a light chain CDR (complementarity determining region alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural

Knowledge and attitude of Indian clinical dental students towards the dental treatment of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS).

Science.gov (United States)

Oberoi, Sukhvinder Singh; Marya, Charu Mohan; Sharma, Nilima; Mohanty, Vikrant; Marwah, Mohita; Oberoi, Avneet

2014-12-01

Oral health care of patients with human immunodeficiency virus (HIV)/acquired immune-deficiency syndrome (AIDS) is a growing area of concern. Information on HIV- and AIDS-related knowledge among dental students provides a crucial foundation for efforts aimed at developing an appropriate dental curriculum on HIV and AIDS. The purpose of this study was to assess the knowledge and attitude of Indian clinical dental students towards the treatment of patients with HIV/AIDS and perceived sources of information regarding HIV-related issues. Data were collected from clinical dental students (third year, fourth year and internship) from three dental institutions in Delhi National Capital Region (NCR). The questions assessed the knowledge and attitude towards treatment of patients with HIV and the perceived source of information related to HIV. The willingness to treat HIV-positive patients among dental students was 67.0%, and 74.20% were confident of treating a patient with HIV/AIDS. The potential problems in rendering treatment to these patients were effect on the attitude of other patients (49.90%) and staff fears (52.50%). The correct knowledge regarding the infection-control practice (barrier technique) was found among only 15.50% of respondents. The respondents had sufficient knowledge regarding the oral manifestations of HIV/AIDS. There was no correlation between the knowledge and attitude score, demonstrating a gap between knowledge and attitude among dental students regarding treatment of HIV-infected patients. Appropriate knowledge has to be delivered through the dental education curriculum, which can instil confidence in students about their ability to manage HIV-positive patients. © 2014 FDI World Dental Federation.

The Effects of Financial Aid Policies on Student Persistence in Taiwanese Higher Education

Science.gov (United States)

Lin, Ching-Hui

2014-01-01

The purpose of this study was to examine the effects of financial aid policies on student persistence between the first and second year at a private four-year postsecondary institution in Taiwan. A two-phase sequential research design was employed with priority was given to the quantitative data--structural equation modeling (SEM). While the…

Examining the Effects of Financial Aid on Student Persistence in Taiwanese Higher Education

Science.gov (United States)

Lin, Ching-Hui

2016-01-01

The purpose of this study was to examine the effects of financial aid policies on student persistence between the first and second year at a private four-year postsecondary institution in Taiwan. A two-phase sequential research design was employed with priority was given to the quantitative data-structural equation modeling (SEM). While the…

Knowledge, attitudes and practices regarding HIV/AIDS among senior secondary school students in Fako Division, South West Region, Cameroon

Directory of Open Access Journals (Sweden)

Colins Kingoum Nubed

2016-08-01

Full Text Available Abstract Background Knowledge, attitudes and practices (KAPs regarding HIV/AIDS is one of the corner stones in the fight against the disease. Youths are most vulnerable to infection because they engage in risky practices due to a lack of adequate information. Thus, evaluating their KAPs will help in designing appropriate prevention strategies. This study was aimed at assessing the KAPs of senior secondary school students in Fako Division, Cameroon, on HIV/AIDS. Methods This was a cross-sectional study carried out on 464 students aged 13–25 years, selected by systematic quota random sampling from some secondary schools in Fako, from April to June 2014, to evaluate their KAPs regarding HIV/AIDS. Participants were drawn from one secondary school in each of the four health districts in Fako. Pre-tested questionnaires were administered to the students to obtain information about their KAPs on HIV/AIDS. Data were analyzed using SPSS version 20.0. Results All respondents were aware of HIV/AIDS. Sources of information varied, the most common being sex education in school. The majority of participants demonstrated an adequate understanding of HIV transmission and prevention. However, misconceptions about routes of transmission were observed in 3.4 to 23.3 % of respondents. Risky behaviors were found among participants as about 60 % practice safe sex and 40 % reported not to. Up to 196 (42.2 % respondents had a history of sexual intercourse of which 108 (56.25 % had used a condom during their last three sexual encounters. About half of the respondents had negative views about HIV infected people. Students with medium (34.3 % and high (62.1 % levels of knowledge were more likely to display positive attitudes Although statistically not significant, we found that as knowledge increased the ability of respondents to report safer sex decreased (95 % CI, P = 0.922. Conclusions Students had a satisfactory level of knowledge on HIV/AIDS prevention

Knowledge, attitudes and practices regarding HIV/AIDS among senior secondary school students in Fako Division, South West Region, Cameroon.

Science.gov (United States)

Nubed, Colins Kingoum; Akoachere, Jane-Francis Tatah Kihla

2016-08-22

Knowledge, attitudes and practices (KAPs) regarding HIV/AIDS is one of the corner stones in the fight against the disease. Youths are most vulnerable to infection because they engage in risky practices due to a lack of adequate information. Thus, evaluating their KAPs will help in designing appropriate prevention strategies. This study was aimed at assessing the KAPs of senior secondary school students in Fako Division, Cameroon, on HIV/AIDS. This was a cross-sectional study carried out on 464 students aged 13-25 years, selected by systematic quota random sampling from some secondary schools in Fako, from April to June 2014, to evaluate their KAPs regarding HIV/AIDS. Participants were drawn from one secondary school in each of the four health districts in Fako. Pre-tested questionnaires were administered to the students to obtain information about their KAPs on HIV/AIDS. Data were analyzed using SPSS version 20.0. All respondents were aware of HIV/AIDS. Sources of information varied, the most common being sex education in school. The majority of participants demonstrated an adequate understanding of HIV transmission and prevention. However, misconceptions about routes of transmission were observed in 3.4 to 23.3 % of respondents. Risky behaviors were found among participants as about 60 % practice safe sex and 40 % reported not to. Up to 196 (42.2 %) respondents had a history of sexual intercourse of which 108 (56.25 %) had used a condom during their last three sexual encounters. About half of the respondents had negative views about HIV infected people. Students with medium (34.3 %) and high (62.1 %) levels of knowledge were more likely to display positive attitudes Although statistically not significant, we found that as knowledge increased the ability of respondents to report safer sex decreased (95 % CI, P = 0.922). Students had a satisfactory level of knowledge on HIV/AIDS prevention. Those with adequate knowledge were more likely to display

PHARUS: A C-band Airborne SAR

NARCIS (Netherlands)

Hoogeboom, P.; Koomen, P.J.; Pouwels, H.; Snoeij, P.

1990-01-01

In The Netherlands a plan to design aircraft and build a polarimetric C-band SAR system of a novel design, called PHARUS (PHased Array Universal SAR) is carried out by three institutes. These institutes are the Physics and Electronics Laboratory TNO in The Hague (prime contractor and project

Knowledge, Attitude, and Practice of Clerical Students with Respect to HIV/AIDS in Iran, 2011.

Science.gov (United States)

Shamsipour, Mansour; Khajehkazemi, Razieh; Haghdoost, Ali Akbar; Setayesh, Hamidreza; KarimanMajd, Sajjad; Mostafavi, Ehsan

2016-02-01

In this study, knowledge and attitude of Iranian clerical students toward HIV and AIDS was assessed. Through a cross-sectional study, 367 clerical students were surveyed, in convenience sampling method, in the Qom seminary in 2011, utilizing a self-administered structured questionnaire. The questionnaire was piloted on 20 clerical student volunteers, internal consistency measured with Cronbach's alpha was 0.89. Participants' scores of knowledge and attitude were calculated out of 100. The level of knowledge in 37.33 % of participants was good (scores >80), whereas 46.05 and 16.62 % had moderate (40 levels of knowledge, respectively. The mean score of knowledge and attitude was 58.29 (95 % CI 56.11-60) and 77.26 (95 % CI 75.92-78.59) out of 100, respectively. A significant correlation was observed between level of knowledge and attitude (r = 0.33, P Knowledge score appeared to be significantly higher in women compared to men (p = 0.04). With an increase in age, the level of knowledge significantly decreased (r = -0.10, P = 0.02). We could also detect a statistically significant relationship between attending educational courses on HIV/AIDS and inclusion of HIV/AIDS topics in the individual's sermons (P knowledge still needs to be improved to enable them to deliver more accurate information to the community during the course of their speeches. Having HIV-related courses as part of their curriculum or aside may contribute a lot to this.

Assessing Tuition and Student Aid Strategies: Using Price-Response Measures to Simulate Pricing Alternatives.

Science.gov (United States)

St. John, Edward P.

1994-01-01

A study used price-response measures from recent national studies to assess college and university pricing (tuition and student aid) alternatives in diverse institutional settings. It is concluded that such analyses are feasible. Analysis indicated limits to "Robin Hood" pricing patterns are predominant in private colleges. Consideration…

Personality traits as predictors of intentions to seek online information about STDs and HIV/AIDS among junior and senior college students in Taiwan.

Science.gov (United States)

Lu, Hung-Yi; Palmgreen, Philip C; Zimmerman, Rick S; Lane, Derek R; Alexander, Linda J

2006-10-01

The purpose of this cross-sectional study is to examine how personality traits such as sensation- seeking and impulsive decision-making affect Taiwanese college students' intentions to seek online information about sexually transmitted diseases (STDs) and human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). Five hundred thirty-five (n = 535) junior and senior college students in Taiwan were recruited and completed self-report questionnaires. This study found high sensation-seekers were more likely to seek information about STDs and HIV/AIDS on the Internet than low sensation-seekers. Impulsive decision-makers were less likely than rational decision-makers to seek information about STDs and HIV/AIDS on the Internet. These findings suggest that personality needs to be considered as an exploratory factor which potentially influences intentions to seek STD and HIV/AIDS information on the Internet among Taiwanese college students.

Effectiveness of a knowledge-contact program in improving nursing students' attitudes and emotional competence in serving people living with HIV/AIDS.

Science.gov (United States)

Yiu, Jessie W; Mak, Winnie W S; Ho, Winnie S; Chui, Ying Yu

2010-07-01

This study compared the effectiveness of an AIDS knowledge-only program (knowledge) with a combined program of AIDS knowledge and contact with people having HIV/AIDS (PHA) (knowledge-contact) in reducing nursing students' stigma and discrimination towards PHA and in enhancing their emotional competence to serve PHA. Eighty-nine nursing students from two universities in Hong Kong were randomly assigned to either the knowledge or the knowledge-contact condition. All participants completed measures of AIDS knowledge, stigmatizing attitudes, fear of contagion, willingness to treat, positive affect, and negative affect at pre-test, post-test, and six-week follow-up. Findings showed that in both groups, significant improvement in AIDS knowledge, stigmatizing attitudes, fear of contagion, willingness to treat, and negative affect were found at post-test. The effects on AIDS knowledge, fear of contagion, willingness to treat, and negative affect were sustained at follow-up for both groups. Intergroup comparisons at post-test showed that the effectiveness of knowledge-contact program was significantly greater than knowledge program in improving stigmatizing attitudes. No significant difference between the two groups was found at follow-up. Findings showed the short-term effect of contact in improving nursing students' attitudes and emotional competence in serving PHA. Implications for research and training of nursing staff were discussed. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

How Money Helps Keep Students in College: The Relationship between Family Finances, Merit-Based Aid, and Retention in Higher Education

Science.gov (United States)

Olbrecht, Alexandre M.; Romano, Christopher; Teigen, Jeremy

2016-01-01

In this paper, we leverage detailed, individual-level student data to understand the relationships between family finances, merit-based aid, and first-year student retention. With three cohorts of student data that comprise family financial status, institutional merit scholarships, and many of the other known correlates of student retention, we…

System for Delivering Student Aid Is Flawed, Many Agree, But What's the Solution?

Science.gov (United States)

Burd, Stephen

1997-01-01

Public officials and student aid experts agree that the federal program delivery system is outdated, inefficient, and vulnerable to fraud, but they disagree on how bad the situation is and whether the Education Department has the structure necessary to fix it. A 1995 project to integrate all federal grant and loan programs into one system has not…

HIV/AIDS Educators: The Challenges and Issues for Namibian Bachelor of Education Students

Science.gov (United States)

McGinty, Sara; Mundy, Karen

2009-01-01

The Life Skills course is offered to Namibian students in grades eight through twelve. It includes lessons on HIV/AIDS, imparting information and equipping them with the necessary psycho-social skills to assist in reducing the risk of becoming infected. Teachers are the impetus for the success of the course. As such, research was undertaken to…

Accelerated Scientific InSAR Processing, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Neva Ridge Technologies proposes to develop a suite of software tools for the analysis of SAR and InSAR data, focused on having a robust and adopted capability well...

Polarimetric SAR image classification based on discriminative dictionary learning model

Science.gov (United States)

Sang, Cheng Wei; Sun, Hong

2018-03-01

Polarimetric SAR (PolSAR) image classification is one of the important applications of PolSAR remote sensing. It is a difficult high-dimension nonlinear mapping problem, the sparse representations based on learning overcomplete dictionary have shown great potential to solve such problem. The overcomplete dictionary plays an important role in PolSAR image classification, however for PolSAR image complex scenes, features shared by different classes will weaken the discrimination of learned dictionary, so as to degrade classification performance. In this paper, we propose a novel overcomplete dictionary learning model to enhance the discrimination of dictionary. The learned overcomplete dictionary by the proposed model is more discriminative and very suitable for PolSAR classification.

Family communication about HIV/AIDS and sexual behaviour ...

African Journals Online (AJOL)

Bivariate analysis showed significant gender differences in sexual activity, condom use, and family communication about HIV/AIDS. Logistic regression analysis showed that student-family communication about HIV/AIDS was not associated with sexual activity. However, communication about HIV/AIDS between students ...

Differences in Knowledge, Attitude, and Behavior towards HIV/AIDS and Sexually Transmitted Infections between Sexually Active Foreign and Chinese Medical Students

Directory of Open Access Journals (Sweden)

Martin Kuete

2016-01-01

Full Text Available Although the prevalence of human immunodeficiency virus (HIV decreased in the last decade worldwide, the number of deaths due to HIV/AIDS and communicable diseases including syphilis, hepatitis, and tuberculosis had dramatically increased in developing countries. Education and behavior are incredibly important factors to prevent these diseases’ spread. This study highlights the range of differences in knowledge, attitude, and behavior of 434 sexually active medical students towards HIV/AIDS and sexually transmitted infections (STIs. Because the surveyed population constitutes the forefront of healthcare providers and was originated from different area of the world, this is the first time a study sought to investigate the behavioral attitude of this group of population irrespective of the three levels of their academic and professional knowledge. Several factors including sociodemographic characteristics, sexual behavior, HIV/AIDS, and STIs related patterns play a key role in medical student attitude and behavior towards people infected with HIV/AIDS and STIs. Our findings add consistent value in prior studies which aimed to stop new infections and also imply further investigations on the management of the studied infections by medical students. The present study arouses much interest among participants and provides evidence of reinforcing medical students’ education on HIV/AIDS and STIs.

Satellite SAR interferometric techniques applied to emergency mapping

Science.gov (United States)

Stefanova Vassileva, Magdalena; Riccardi, Paolo; Lecci, Daniele; Giulio Tonolo, Fabio; Boccardo Boccardo, Piero; Chiesa, Giuliana; Angeluccetti, Irene

2017-04-01

This paper aim to investigate the capabilities of the currently available SAR interferometric algorithms in the field of emergency mapping. Several tests have been performed exploiting the Copernicus Sentinel-1 data using the COTS software ENVI/SARscape 5.3. Emergency Mapping can be defined as "creation of maps, geo-information products and spatial analyses dedicated to providing situational awareness emergency management and immediate crisis information for response by means of extraction of reference (pre-event) and crisis (post-event) geographic information/data from satellite or aerial imagery". The conventional differential SAR interferometric technique (DInSAR) and the two currently available multi-temporal SAR interferometric approaches, i.e. Permanent Scatterer Interferometry (PSI) and Small BAseline Subset (SBAS), have been applied to provide crisis information useful for the emergency management activities. Depending on the considered Emergency Management phase, it may be distinguished between rapid mapping, i.e. fast provision of geospatial data regarding the area affected for the immediate emergency response, and monitoring mapping, i.e. detection of phenomena for risk prevention and mitigation activities. In order to evaluate the potential and limitations of the aforementioned SAR interferometric approaches for the specific rapid and monitoring mapping application, five main factors have been taken into account: crisis information extracted, input data required, processing time and expected accuracy. The results highlight that DInSAR has the capacity to delineate areas affected by large and sudden deformations and fulfills most of the immediate response requirements. The main limiting factor of interferometry is the availability of suitable SAR acquisition immediately after the event (e.g. Sentinel-1 mission characterized by 6-day revisiting time may not always satisfy the immediate emergency request). PSI and SBAS techniques are suitable to produce

Forest parameter estimation using polarimetric SAR interferometry techniques at low frequencies

International Nuclear Information System (INIS)

Lee, Seung-Kuk

2013-01-01

Polarimetric Synthetic Aperture Radar Interferometry (Pol-InSAR) is an active radar remote sensing technique based on the coherent combination of both polarimetric and interferometric observables. The Pol-InSAR technique provided a step forward in quantitative forest parameter estimation. In the last decade, airborne SAR experiments evaluated the potential of Pol-InSAR techniques to estimate forest parameters (e.g., the forest height and biomass) with high accuracy over various local forest test sites. This dissertation addresses the actual status, potentials and limitations of Pol-InSAR inversion techniques for 3-D forest parameter estimations on a global scale using lower frequencies such as L- and P-band. The multi-baseline Pol-InSAR inversion technique is applied to optimize the performance with respect to the actual level of the vertical wave number and to mitigate the impact of temporal decorrelation on the Pol-InSAR forest parameter inversion. Temporal decorrelation is a critical issue for successful Pol-InSAR inversion in the case of repeat-pass Pol-InSAR data, as provided by conventional satellites or airborne SAR systems. Despite the limiting impact of temporal decorrelation in Pol-InSAR inversion, it remains a poorly understood factor in forest height inversion. Therefore, the main goal of this dissertation is to provide a quantitative estimation of the temporal decorrelation effects by using multi-baseline Pol-InSAR data. A new approach to quantify the different temporal decorrelation components is proposed and discussed. Temporal decorrelation coefficients are estimated for temporal baselines ranging from 10 minutes to 54 days and are converted to height inversion errors. In addition, the potential of Pol-InSAR forest parameter estimation techniques is addressed and projected onto future spaceborne system configurations and mission scenarios (Tandem-L and BIOMASS satellite missions at L- and P-band). The impact of the system parameters (e.g., bandwidth

Human monoclonal antibody as prophylaxis for SARS coronavirus infection in ferrets

NARCIS (Netherlands)

ter Meulen, Jan; Bakker, Alexander B. H.; van den Brink, Edward N.; Weverling, Gerrit J.; Martina, Byron E. E.; Haagmans, Bart L.; Kuiken, Thijs; de Kruif, John; Preiser, Wolfgang; Spaan, Willy; Gelderblom, Hans R.; Goudsmit, Jaap; Osterhaus, Albert D. M. E.

2004-01-01

SARS coronavirus continues to cause sporadic cases of severe acute respiratory syndrome (SARS) in China. No active or passive immunoprophylaxis for disease induced by SARS coronavirus is available. We investigated prophylaxis of SARS coronavirus infection with a neutralising human monoclonal

Infrastructure monitoring with spaceborne SAR sensors

CERN Document Server

ANGHEL, ANDREI; CACOVEANU, REMUS

2017-01-01

This book presents a novel non-intrusive infrastructure monitoring technique based on the detection and tracking of scattering centers in spaceborne SAR images. The methodology essentially consists of refocusing each available SAR image on an imposed 3D point cloud associated to the envisaged infrastructure element and identifying the reliable scatterers to be monitored by means of four dimensional (4D) tomography. The methodology described in this book provides a new perspective on infrastructure monitoring with spaceborne SAR images, is based on a standalone processing chain, and brings innovative technical aspects relative to conventional approaches. The book is intended primarily for professionals and researchers working in the area of critical infrastructure monitoring by radar remote sensing.

Knowledge, risk perception of AIDS and reported sexual behaviour among students in secondary schools and colleges in Tanzania.

Science.gov (United States)

Maswanya, E S; Moji, K; Horiguchi, I; Nagata, K; Aoyagi, K; Honda, S; Takemoto, T

1999-04-01

A questionnaire survey was carried out among 1041 students in secondary schools and colleges in Dar-es-Salaam, Tanzania to evaluate the relationship between HIV-risky sexual behaviour and anti-condom bias, as well as with AIDS-related information, knowledge, perceptions and attitudes. Self-reportedly, 54% of students (75% of the boys and 40% of the girls) were sexually active, 39% had a regular sexual partner and 13% had multiple partners in the previous year. The condom use rate was higher than previous reports. However, 30% of sexually active respondents did not always use condoms (Risk-1 behaviour) and 35% of those with multiple partners in the previous year did not always use condoms (Risk-2 behaviour). Multiple logistic regression analyses indicated that 'sex partner hates condom' had association with both Risk-1 behaviour (OR 2.47; 95% CI 1.58-3.85) and Risk-2 behaviour (OR 2.47; 95% CI 1.10-5.48). 'Use of condom prevents HIV infection' also had association with both Risk-1 behaviour (OR 2.09; 95% CI 1.19-3.67) and Risk-2 behaviour (OR 3.73; 95% CI 1.28-11.03). Students engaging in risky behaviour were aware of the risk, even though they failed to change their behaviour. Reasons for the AIDS epidemic among Tanzanian students and the importance of more effective AIDS education are also discussed.

Mapping mountain meadow with high resolution and polarimetric SAR data

International Nuclear Information System (INIS)

Tian, Bangsen; Li, Zhen; Xu, Juan; Fu, Sitao; Liu, Jiuli

2014-01-01

This paper presents a method to map the large grassland in the eastern margin of the Tibetan Plateau with the high resolution polarimetric SAR (PolSAR) imagery. When PolSAR imagery is used for land cover classification, the brightness of a SAR image is affected by topography due to varying projection between ground and image coordinates. The objective of this paper is twofold: (1) we first extend the theory of SAR terrain correction to the polarimetric case, to utilize the entire available polarimetric signature, where correction is performed explicitly based on a matrix format like covariance matrix. (2) Next, the orthoectified PolSAR is applied to classify mountain meadow and investigate the potential of PolSAR in mapping grassland. In this paper, the gamma naught radiometric correction estimates the local illuminated area at each grid point in the radar geometry. Then, each element of the coherency matrix is divided by the local area to produce a polarimetric product. Secondly, the impact of radiometric correction upon classification accuracy is investigated. A supervised classification is performed on the orthorectified Radarsat-2 PolSAR to map the spatial distribution of meadow and evaluate monitoring capabilities of mountain meadow

Geometric calibration of ERS satellite SAR images

DEFF Research Database (Denmark)

Mohr, Johan Jacob; Madsen, Søren Nørvang

2001-01-01

Geometric calibration of the European Remote Sensing (ERS) Satellite synthetic aperture radar (SAR) slant range images is important in relation to mapping areas without ground reference points and also in relation to automated processing. The relevant SAR system parameters are discussed...

The Differential Effects of Financial Aid on Degree Completion by Gender

Science.gov (United States)

Gross, Jacob P. K.; Berry, Matthew; Reynolds, Pauline

2015-01-01

Financial aid and student success are interrelated and essential components of strategic enrollment management. From an economic perspective, by reducing the price students pay, financial aid affects student demand for education. However, financial aid also has nonmonetary effects. For example, students receiving institutional scholarships may…

Improved SAR Image Coregistration Using Pixel-Offset Series

KAUST Repository

Wang, Teng

2014-03-14

Synthetic aperture radar (SAR) image coregistration is a key procedure before interferometric SAR (InSAR) time-series analysis can be started. However, many geophysical data sets suffer from severe decorrelation problems due to a variety of reasons, making precise coregistration a nontrivial task. Here, we present a new strategy that uses a pixel-offset series of detected subimage patches dominated by point-like targets (PTs) to improve SAR image coregistrations. First, all potentially coherent image pairs are coregistered in a conventional way. In this step, we propose a coregistration quality index for each image to rank its relative “significance” within the data set and to select a reference image for the SAR data set. Then, a pixel-offset series of detected PTs is made from amplitude maps to improve the geometrical mapping functions. Finally, all images are resampled depending on the pixel offsets calculated from the updated geometrical mapping functions. We used images from a rural region near the North Anatolian Fault in eastern Turkey to test the proposed method, and clear coregistration improvements were found based on amplitude stability. This enhanced the fact that the coregistration strategy should therefore lead to improved InSAR time-series analysis results.

Improved SAR Image Coregistration Using Pixel-Offset Series

KAUST Repository

Wang, Teng; Jonsson, Sigurjon; Hanssen, Ramon F.

2014-01-01

Synthetic aperture radar (SAR) image coregistration is a key procedure before interferometric SAR (InSAR) time-series analysis can be started. However, many geophysical data sets suffer from severe decorrelation problems due to a variety of reasons, making precise coregistration a nontrivial task. Here, we present a new strategy that uses a pixel-offset series of detected subimage patches dominated by point-like targets (PTs) to improve SAR image coregistrations. First, all potentially coherent image pairs are coregistered in a conventional way. In this step, we propose a coregistration quality index for each image to rank its relative “significance” within the data set and to select a reference image for the SAR data set. Then, a pixel-offset series of detected PTs is made from amplitude maps to improve the geometrical mapping functions. Finally, all images are resampled depending on the pixel offsets calculated from the updated geometrical mapping functions. We used images from a rural region near the North Anatolian Fault in eastern Turkey to test the proposed method, and clear coregistration improvements were found based on amplitude stability. This enhanced the fact that the coregistration strategy should therefore lead to improved InSAR time-series analysis results.

URBAN MODELLING PERFORMANCE OF NEXT GENERATION SAR MISSIONS

Directory of Open Access Journals (Sweden)

U. G. Sefercik

2017-09-01

Full Text Available In synthetic aperture radar (SAR technology, urban mapping and modelling have become possible with revolutionary missions TerraSAR-X (TSX and Cosmo-SkyMed (CSK since 2007. These satellites offer 1m spatial resolution in high-resolution spotlight imaging mode and capable for high quality digital surface model (DSM acquisition for urban areas utilizing interferometric SAR (InSAR technology. With the advantage of independent generation from seasonal weather conditions, TSX and CSK DSMs are much in demand by scientific users. The performance of SAR DSMs is influenced by the distortions such as layover, foreshortening, shadow and double-bounce depend up on imaging geometry. In this study, the potential of DSMs derived from convenient 1m high-resolution spotlight (HS InSAR pairs of CSK and TSX is validated by model-to-model absolute and relative accuracy estimations in an urban area. For the verification, an airborne laser scanning (ALS DSM of the study area was used as the reference model. Results demonstrated that TSX and CSK urban DSMs are compatible in open, built-up and forest land forms with the absolute accuracy of 8–10 m. The relative accuracies based on the coherence of neighbouring pixels are superior to absolute accuracies both for CSK and TSX.

InSAR deformation monitoring of high risk landslides

Science.gov (United States)

Singhroy, V.; Li, J.

2013-05-01

During the past year there were at least twenty five media reports of landslides and seismic activities some fatal, occurring in various areas in Canada. These high risk geohazards sites requires high resolution monitoring both spatially and temporally for mitigation purposes, since they are near populated areas and energy, transportation and communication corridors. High resolution air photos, lidar and satellite images are quite common in areas where the landslides can be fatal. Radar interferometry (InSAR) techniques using images from several radar satellites are increasingly being used in slope stability assessment. This presentation provides examples of using high-resolution (1-3m) frequent revisits InSAR techniques from RADARSAT 2 and TerraSAR X to monitor several types of high-risk landslides affecting transportation and energy corridors and populated areas. We have analyses over 200 high resolution InSAR images over a three year period on geologically different landslides. The high-resolution InSAR images are effective in characterizing differential motion within these low velocity landslides. The low velocity landslides become high risk during the active wet spring periods. The wet soils are poor coherent targets and corner reflectors provide an effective means of InSAR monitoring the slope activities.

Financial Aid Tipping Points: An Analysis of Aid and Academic Achievement at a California Community College

Science.gov (United States)

Coria, Elizabeth; Hoffman, John L.

2016-01-01

The purpose of this study was to explore relationships between financial aid awards and measures of student academic achievement. Financial aid and academic records for 11,956 students attending an urban California community college were examined and analyzed using simultaneous linear regression and two-way factorial ANOVAs. Findings revealed a…

Spacial Variation in SAR Images of Different Resolution for Agricultural Fields

DEFF Research Database (Denmark)

Sandholt, Inge; Skriver, Henning

1999-01-01

The spatial variation in two types of Synthetic Aperture Radar (SAR) images covering agricultural fields is analysed. C-band polarimetric SAR data from the Danish airborne SAR, EMISAR, have been compared to space based ERS-1 C-band SAR with respect to scale and effect of polarization. The general...

hPEPT1 Affinity and Translocation of Selected Gln-Sar and Glu-Sar Dipeptide Derivatives

DEFF Research Database (Denmark)

Eriksson, A. H.; Elm, Peter L.; Begtrup, Mikael

2005-01-01

using 14C-labeled Gly-Sar. Translocation was measured as fluorescence ratios induced by the substrates using the fluorescent probe BCECF and an epifluorescence microscope setup. All compounds showed high affinity to hPEPT1, but only the amides l-Gln(N,N-dimethyl)-Sar and l-Gln(N-piperidinyl)-Sar were...... been suggested. However, these are not necessarily predictive of compounds that are actually translocated by hPEPT1. More information on affinity to and translocation via hPEPT1 of side-chain-modified dipeptides may be gained by conducting a study of selected dipeptide derivatives with variety in size...... translocated by hPEPT1. hPEPT1 is very susceptible to modifications of the N-terminal amino acid side chain of dipeptidomimetic substrates, in terms of achieving compounds with high affinity for the transporter. However, as affinity is not predictive of translocation, derivatization in this position must...

The experience of SARS-related stigma at Amoy Gardens.

Science.gov (United States)

Lee, Sing; Chan, Lydia Y Y; Chau, Annie M Y; Kwok, Kathleen P S; Kleinman, Arthur

2005-11-01

Severe Acute Respiratory Syndrome (SARS) possesses characteristics that render it particularly prone to stigmatization. SARS-related stigma, despite its salience for public health and stigma research, has had little examination. This study combines survey and case study methods to examine subjective stigma among residents of Amoy Gardens (AG), the first officially recognized site of community outbreak of SARS in Hong Kong. A total of 903 residents of AG completed a self-report questionnaire derived from two focus groups conducted toward the end of the 3-month outbreak. Case studies of two residents who lived in Block E, the heart of the SARS epidemic at AG, complement the survey data. Findings show that stigma affected most residents and took various forms of being shunned, insulted, marginalized, and rejected in the domains of work, interpersonal relationships, use of services and schooling. Stigma was also associated with psychosomatic distress. Residents' strategies for diminishing stigma varied with gender, age, education, occupation, and proximity to perceived risk factors for SARS such as residential location, previous SARS infection and the presence of ex-SARS household members. Residents attributed stigma to government mismanagement, contagiousness of the mysterious SARS virus, and alarmist media reporting. Stigma clearly decreased, but never completely disappeared, after the outbreak. The findings confirm and add to existing knowledge on the varied origins, correlates, and impacts of stigma. They also highlight the synergistic roles of inconsistent health policy responses and risk miscommunication by the media in rapidly amplifying stigma toward an unfamiliar illness. While recognizing the intrinsically stigmatizing nature of public health measures to control SARS, we recommend that a consistent inter-sectoral approach is needed to minimize stigma and to make an effective health response to future outbreaks.

Estimating Elevation Angles From SAR Crosstalk

Science.gov (United States)

Freeman, Anthony

1994-01-01

Scheme for processing polarimetric synthetic-aperture-radar (SAR) image data yields estimates of elevation angles along radar beam to target resolution cells. By use of estimated elevation angles, measured distances along radar beam to targets (slant ranges), and measured altitude of aircraft carrying SAR equipment, one can estimate height of target terrain in each resolution cell. Monopulselike scheme yields low-resolution topographical data.

Opiniões de jovens universitários sobre pessoas com HIV/AIDS: um estudo exploratório sobre preconceito Opinion of college students about persons with HIV/AIDS: an exploratory study about prejudice

Directory of Open Access Journals (Sweden)

Eliane Maria Fleury Seidl

2010-04-01

Full Text Available O estudo objetivou identificar opiniões de estudantes universitários sobre pessoas vivendo com HIV/AIDS, comparando-as segundo sexo e área de formação. Participaram 503 universitários, 53% mulheres, das áreas de humanas, exatas e da saúde. Afirmativas que versavam sobre pessoas soropositivas foram apresentadas, com respostas em escala Likert de cinco pontos. Com relação às afirmativas que versavam sobre demissão do emprego de pessoa infectada pelo vírus HIV e proibição de crianças soropositivas frequentarem escola, alunos da área de saúde tenderam a discordar, com diferença significativa em relação aos participantes de humanas e exatas. Nas questões "mulheres portadoras do HIV/AIDS deveriam evitar filhos" e "uma pessoa infectada pelo vírus da AIDS é responsável por essa condição de saúde", os grupos se distribuíram de modo equitativo. Não se observaram diferenças relevantes entre homens e mulheres. Há necessidade de maior informação e debate para modificar opiniões preconceituosas em relação a pessoas com HIV/AIDS entre universitários.The aim of this research was to identify the opinion of college students about people living with HIV/AIDS, according to gender and graduation fields. The participants were 503 university students, 53% of which were women, from humanities, exact sciences and health sciences fields. A questionnaire was applied with a Likert scale of five points. The questions: the employer should dismiss an employee and HIV+ children should be forbidden to go to school were answered with disagreement by health sciences students, with significant differences from the other groups of students. The questions: women infected by HIV should avoid pregnancy and a person infected by HIV is responsible for his/her health condition, the agreeing and disagreeing answers had a similar distribution among the groups of students. No differences between genders were found. The results indicate the need to

SAR Study of Mobile Phones as a function of Antenna Q

DEFF Research Database (Denmark)

Bahramzy, Pevand; Svendsen, Simon; Jagielski, Ole

2015-01-01

density associated with high-Q antennas. The higher energy stored in the electric and magnetic near-field components can result in higher SAR. Hence, SAR study of high-Q antennas is necessary which, if not addressed, might not comply with the SAR safety guidelines. In this paper, SAR as a function...

SAR calculation using FDTD simulations

OpenAIRE

Ferro, Francisco Nabais; Pinto, Guilherme Taveira; Pinho, Pedro

2009-01-01

The main intend of this work, is to determinate the Specific Absorption Rate (SAR) on human head tissues exposed to radiation caused by sources of 900 and 1800MHz, since those are the typical frequencies for mobile communications systems nowadays. In order to determinate the SAR, has been used the FDTD (Finite Difference Time Domain), which is a numeric method in time domain, obtained from the Maxwell equations in differential mode. In order to do this, a computational model from the human he...

Using Peer-Mediated Literacy-Based Behavioral Interventions to Increase First Aid Safety Skills in Students With Developmental Disabilities.

Science.gov (United States)

Kearney, Kelly B; Brady, Michael P; Hall, Kalynn; Honsberger, Toby

2017-08-01

Many adolescents with developmental disabilities do not learn the safety skills needed to maintain physical well-being in domestic and community environments. Literacy-based behavioral interventions (LBBIs) that combine print, pictures, and behavioral rehearsal are effective for promoting acquisition and maintenance of self-care skills, but have not been investigated as safety skill intervention. Also, LBBIs have primarily been implemented by teachers and other professionals. In this study, a peer partner was taught to deliver an LBBI story to students so they would learn to perform a basic first aid routine: cleaning and dressing a wound. Results showed that students' accuracy with the first aid routine increased after a peer delivered the LBBI instructional package, and maintained after the peer stopped delivering it. This study demonstrates the effectiveness of the LBBI instructional package for teaching first aid safety skills, and extends previous research showing the efficacy of peers in delivering this intervention.

High-Level Performance Modeling of SAR Systems

Science.gov (United States)

Chen, Curtis

2006-01-01

SAUSAGE (Still Another Utility for SAR Analysis that s General and Extensible) is a computer program for modeling (see figure) the performance of synthetic- aperture radar (SAR) or interferometric synthetic-aperture radar (InSAR or IFSAR) systems. The user is assumed to be familiar with the basic principles of SAR imaging and interferometry. Given design parameters (e.g., altitude, power, and bandwidth) that characterize a radar system, the software predicts various performance metrics (e.g., signal-to-noise ratio and resolution). SAUSAGE is intended to be a general software tool for quick, high-level evaluation of radar designs; it is not meant to capture all the subtleties, nuances, and particulars of specific systems. SAUSAGE was written to facilitate the exploration of engineering tradeoffs within the multidimensional space of design parameters. Typically, this space is examined through an iterative process of adjusting the values of the design parameters and examining the effects of the adjustments on the overall performance of the system at each iteration. The software is designed to be modular and extensible to enable consideration of a variety of operating modes and antenna beam patterns, including, for example, strip-map and spotlight SAR acquisitions, polarimetry, burst modes, and squinted geometries.

Teaching Aids: Struggling with/through Student Resistances in Psychology Curricula in South African Universities

Science.gov (United States)

Wilbraham, Lindy

2016-01-01

African universities have been called to respond to the social issues of trauma, adversity, injustice and inequality that trouble their embedding communities, their staff and their students. The need for South African universities to respond to HIV/Aids (in particular) includes the opening up of new knowledge about and ways of managing the impacts…

Automatic Coregistration for Multiview SAR Images in Urban Areas

Science.gov (United States)

Xiang, Y.; Kang, W.; Wang, F.; You, H.

2017-09-01

Due to the high resolution property and the side-looking mechanism of SAR sensors, complex buildings structures make the registration of SAR images in urban areas becomes very hard. In order to solve the problem, an automatic and robust coregistration approach for multiview high resolution SAR images is proposed in the paper, which consists of three main modules. First, both the reference image and the sensed image are segmented into two parts, urban areas and nonurban areas. Urban areas caused by double or multiple scattering in a SAR image have a tendency to show higher local mean and local variance values compared with general homogeneous regions due to the complex structural information. Based on this criterion, building areas are extracted. After obtaining the target regions, L-shape structures are detected using the SAR phase congruency model and Hough transform. The double bounce scatterings formed by wall and ground are shown as strong L- or T-shapes, which are usually taken as the most reliable indicator for building detection. According to the assumption that buildings are rectangular and flat models, planimetric buildings are delineated using the L-shapes, then the reconstructed target areas are obtained. For the orignal areas and the reconstructed target areas, the SAR-SIFT matching algorithm is implemented. Finally, correct corresponding points are extracted by the fast sample consensus (FSC) and the transformation model is also derived. The experimental results on a pair of multiview TerraSAR images with 1-m resolution show that the proposed approach gives a robust and precise registration performance, compared with the orignal SAR-SIFT method.

3D Monitoring of Buildings Using TerraSAR-X InSAR, DInSAR and PolSAR Capacities

Directory of Open Access Journals (Sweden)

Flora Weissgerber

2017-09-01

Full Text Available The rapid expansion of cities increases the need of urban remote sensing for a large scale monitoring. This paper provides greater understanding of how TerraSAR-X (TSX high-resolution abilities enable to reach the spatial precision required to monitor individual buildings, through the use of a 4 year temporal stack of 100 images over Paris (France. Three different SAR modes are investigated for this purpose. First a method involving a whole time-series is proposed to measure realistic heights of buildings. Then, we show that the small wavelength of TSX makes the interferometric products very sensitive to the ordinary building-deformation, and that daily deformation can be measured over the entire building with a centimetric accuracy, and without any a priori on the deformation evolution, even when neglecting the impact of the atmosphere. Deformations up to 4 cm were estimated for the Eiffel Tower and up to 1 cm for other lower buildings. These deformations were analyzed and validated with weather and in situ local data. Finally, four TSX polarimetric images were used to investigate geometric and dielectric properties of buildings under the deterministic framework. Despite of the resolution loss of this mode, the possibility to estimate the structural elements of a building orientations and their relative complexity in the spatial organization are demonstrated.

77 FR 48970 - Notice of Proposed Information Collection Requests; Federal Student Aid; 2013-2014 Federal...

Science.gov (United States)

2012-08-15

... record for system-generated applicants under this corrections. correction type as these are system-based... change the directly in the CPS system by postsecondary institutions listed on a FSAIC representative... as it relates to the application process for federal student aid. The Applicant Burden Model (ABM...

78 FR 26334 - Agency Information Collection Activities; Comment Request; 2014-2015 Federal Student Aid Application

Science.gov (United States)

2013-05-06

... on their behalf through FOTW. FAA Access Online tool that a Submitted through financial aid www... financial reporting forms as described in this subsection to be used for application and reapplication to determine the need and eligibility of a student for financial assistance . . .''. The determination of need...

Relevant Scatterers Characterization in SAR Images

Science.gov (United States)

Chaabouni, Houda; Datcu, Mihai

2006-11-01

Recognizing scenes in a single look meter resolution Synthetic Aperture Radar (SAR) images, requires the capability to identify relevant signal signatures in condition of variable image acquisition geometry, arbitrary objects poses and configurations. Among the methods to detect relevant scatterers in SAR images, we can mention the internal coherence. The SAR spectrum splitted in azimuth generates a series of images which preserve high coherence only for particular object scattering. The detection of relevant scatterers can be done by correlation study or Independent Component Analysis (ICA) methods. The present article deals with the state of the art for SAR internal correlation analysis and proposes further extensions using elements of inference based on information theory applied to complex valued signals. The set of azimuth looks images is analyzed using mutual information measures and an equivalent channel capacity is derived. The localization of the "target" requires analysis in a small image window, thus resulting in imprecise estimation of the second order statistics of the signal. For a better precision, a Hausdorff measure is introduced. The method is applied to detect and characterize relevant objects in urban areas.

An analytical solution for improved HIFU SAR estimation

International Nuclear Information System (INIS)

Dillon, C R; Vyas, U; Christensen, D A; Roemer, R B; Payne, A

2012-01-01

Accurate determination of the specific absorption rates (SARs) present during high intensity focused ultrasound (HIFU) experiments and treatments provides a solid physical basis for scientific comparison of results among HIFU studies and is necessary to validate and improve SAR predictive software, which will improve patient treatment planning, control and evaluation. This study develops and tests an analytical solution that significantly improves the accuracy of SAR values obtained from HIFU temperature data. SAR estimates are obtained by fitting the analytical temperature solution for a one-dimensional radial Gaussian heating pattern to the temperature versus time data following a step in applied power and evaluating the initial slope of the analytical solution. The analytical method is evaluated in multiple parametric simulations for which it consistently (except at high perfusions) yields maximum errors of less than 10% at the center of the focal zone compared with errors up to 90% and 55% for the commonly used linear method and an exponential method, respectively. For high perfusion, an extension of the analytical method estimates SAR with less than 10% error. The analytical method is validated experimentally by showing that the temperature elevations predicted using the analytical method's SAR values determined for the entire 3D focal region agree well with the experimental temperature elevations in a HIFU-heated tissue-mimicking phantom. (paper)

Influence of a persuasive strategy on nursing students' beliefs and attitudes toward provision of care to people living with HIV/AIDS.

Science.gov (United States)

Valois, P; Turgeon, H; Godin, G; Blondeau, D; Cote, F

2001-11-01

Based on the theory of planned behavior and the elaboration likelihood model, the aim of this study was to verify the effect of persuasive messages on nursing students' beliefs and attitudes regarding provision of care to people living with HIV/AIDS. The assumption was that a persuasive communication strategy induces a constructive change in beliefs and attitudes regarding provision of care. Baseline data collection was performed among a group of 74 nursing students (experimental group = 27; control group = 47). The questionnaire assessed the variables of the theory of planned behavior (i.e., beliefs, attitudes, perceived behavioral control). The results confirmed that persuasive messages generated a change in beliefs and attitudes of the nursing students concerning providing care to people living with HIV/AIDS. It appears that this strategy of modifying behavioral predispositions is effective and generates cognitive and affective changes. Therefore, educational programs should take these observations into consideration to ensure that future nurses are better prepared to provide appropriate care to people living with HIV/AIDS.

High School Students' Written Argumentation Qualities with Problem-Based Computer-Aided Material (PBCAM) Designed about Human Endocrine System

Science.gov (United States)

Vekli, Gülsah Sezen; Çimer, Atilla

2017-01-01

This study investigated development of students' scientific argumentation levels in the applications made with Problem-Based Computer-Aided Material (PBCAM) designed about Human Endocrine System. The case study method was used: The study group was formed of 43 students in the 11th grade of the science high school in Rize. Human Endocrine System…

A patient with asymptomatic severe acute respiratory syndrome (SARS) and antigenemia from the 2003-2004 community outbreak of SARS in Guangzhou, China.

Science.gov (United States)

Che, Xiao-yan; Di, Biao; Zhao, Guo-ping; Wang, Ya-di; Qiu, Li-wen; Hao, Wei; Wang, Ming; Qin, Peng-zhe; Liu, Yu-fei; Chan, Kwok-hong; Cheng, Vincent C C; Yuen, Kwok-yung

2006-07-01

An asymptomatic case of severe acute respiratory syndrome (SARS) occurred early in 2004, during a community outbreak of SARS in Guangzhou, China. This was the first time that a case of asymptomatic SARS was noted in an individual with antigenemia and seroconversion. The asymptomatic case patient and the second index case patient with SARS in the 2003-2004 outbreak both worked in the same restaurant, where they served palm civets, which were found to carry SARS-associated coronaviruses. Epidemiological information and laboratory findings suggested that the findings for the patient with asymptomatic infection, together with the findings from previously reported serological analyses of handlers of wild animals and the 4 index case patients from the 2004 community outbreak, reflected a likely intermediate phase of animal-to-human transmission of infection, rather than a case of human-to-human transmission. This intermediate phase may be a critical stage for virus evolution and disease prevention.

Scattering Mechanism Extraction by a Modified Cloude-Pottier Decomposition for Dual Polarization SAR

Directory of Open Access Journals (Sweden)

Kefeng Ji

2015-06-01

Full Text Available Dual polarization is a typical operational mode of polarimetric synthetic aperture radar (SAR. However, few studies have considered the scattering mechanism extraction of dual-polarization SARs. A modified Cloude-Pottier decomposition is proposed to investigate the performance of the scattering mechanism extraction of dual-polarization SARs. It is theoretically demonstrated that only HH-VV SAR can discriminate the three canonical scattering mechanisms from an isotropic surface, horizontal dipole, and isotropic dihedral. Various experiments are conducted using 21 scenes from real datasets acquired by AIRSAR, Convair-580 SAR, EMISAR, E-SAR, Pi-SAR, and RADARSAT-2. Division of the dual-polarization H-α plane is experimentally obtained. The lack of cross-polarization induces the diffusion of scattering mechanisms and their overlap in the HH-VV H-α plane. However, the performance of HH-VV SAR for extracting scattering mechanisms is acceptable. Thus, HH-VV SAR is a suitable alternative to full-polarization SAR in certain cases. Meanwhile, the extraction performance of the other two dual-polarization SARs is badly degraded due to the lack of co-polarization. Therefore, HH-HV and HV-VV SARs cannot effectively extract the scattering mechanisms in the H-α plane.

Your Most Essential Audiovisual Aid--Yourself!

Science.gov (United States)

Hamp-Lyons, Elizabeth

2012-01-01

Acknowledging that an interested and enthusiastic teacher can create excitement for students and promote learning, the author discusses how teachers can improve their appearance, and, consequently, how their students perceive them. She offers concrete suggestions on how a teacher can be both a "visual aid" and an "audio aid" in the classroom.…

AUTOMATIC COREGISTRATION FOR MULTIVIEW SAR IMAGES IN URBAN AREAS

Directory of Open Access Journals (Sweden)

Y. Xiang

2017-09-01

Full Text Available Due to the high resolution property and the side-looking mechanism of SAR sensors, complex buildings structures make the registration of SAR images in urban areas becomes very hard. In order to solve the problem, an automatic and robust coregistration approach for multiview high resolution SAR images is proposed in the paper, which consists of three main modules. First, both the reference image and the sensed image are segmented into two parts, urban areas and nonurban areas. Urban areas caused by double or multiple scattering in a SAR image have a tendency to show higher local mean and local variance values compared with general homogeneous regions due to the complex structural information. Based on this criterion, building areas are extracted. After obtaining the target regions, L-shape structures are detected using the SAR phase congruency model and Hough transform. The double bounce scatterings formed by wall and ground are shown as strong L- or T-shapes, which are usually taken as the most reliable indicator for building detection. According to the assumption that buildings are rectangular and flat models, planimetric buildings are delineated using the L-shapes, then the reconstructed target areas are obtained. For the orignal areas and the reconstructed target areas, the SAR-SIFT matching algorithm is implemented. Finally, correct corresponding points are extracted by the fast sample consensus (FSC and the transformation model is also derived. The experimental results on a pair of multiview TerraSAR images with 1-m resolution show that the proposed approach gives a robust and precise registration performance, compared with the orignal SAR-SIFT method.

Monitoring of Three Case Studies of Creeping Landslides in Ecuador using L-band SAR Interferometry (InSAR)

Science.gov (United States)

Mayorga Torres, T. M.; Mohseni Aref, M.

2015-12-01

Tannia Mayorga Torres1,21 Universidad Central del Ecuador. Faculty of Geology, Mining, Oil, and Environment 2 Hubert H. Humphrey Fellowship 2015-16 IntroductionLandslides lead to human and economic losses across the country, mainly in the winter season. On the other hand, satellite radar data has cost-effective benefits due to open-source software and free availability of data. With the purpose of establishing an early warning system of landslide-related surface deformation, three case studies were designed in the Coast, Sierra (Andean), and Oriente (jungle) regions. The objective of this work was to assess the capability of L-band InSAR to get phase information. For the calculation of the interferograms in Repeat Orbit Interferometry PACkage, the displacement was detected as the error and was corrected. The coherence images (Figure 1) determined that L-band is suitable for InSAR processing. Under this frame, as a first approach, the stacking DInSAR technique [1] was applied in the case studies [2]; however, due to lush vegetation and steep topography, it is necessary to apply advanced InSAR techniques [3]. The purpose of the research is to determine a pattern of data acquisition and successful results to understand the spatial and temporal ground movements associated with landslides. The further work consists of establishing landslide inventories to combine phases of SAR images to generate maps of surface deformation in Tumba-San Francisco and Guarumales to compare the results with ground-based measurements to determine the maps' accuracy. References[1] Sandwell D., Price E. (1998). Phase gradient approach to stacking interferograms. Journal of Geophysical Research, Vol. 103, N. B12, pp. 30,183-30,204. [2] Mayorga T., Platzeck G. (2014). Using DInSAR as a tool to detect unstable terrain areas in an Andes region in Ecuador. NH3.5-Blue Poster B298, Vol. 16, EGU2014-16203. Austria. [3] Wasowski J., Bovenga F. (2014). Investigating landslides and unstable slopes with

Applications of SAR Interferometry in Earth and Environmental Science Research.

Science.gov (United States)

Zhou, Xiaobing; Chang, Ni-Bin; Li, Shusun

2009-01-01

This paper provides a review of the progress in regard to the InSAR remote sensing technique and its applications in earth and environmental sciences, especially in the past decade. Basic principles, factors, limits, InSAR sensors, available software packages for the generation of InSAR interferograms were summarized to support future applications. Emphasis was placed on the applications of InSAR in seismology, volcanology, land subsidence/uplift, landslide, glaciology, hydrology, and forestry sciences. It ends with a discussion of future research directions.

SARS Risk Perception, Knowledge, Precautions, and Information Sources, the Netherlands

Science.gov (United States)

Aro, Arja R.; Oenema, Anke; de Zwart, Onno; Richardus, Jan Hendrik; Bishop, George D.

2004-01-01

Severe acute respiratory syndrome (SARS)–related risk perceptions, knowledge, precautionary actions, and information sources were studied in the Netherlands during the 2003 SARS outbreak. Although respondents were highly aware of the SARS outbreak, the outbreak did not result in unnecessary precautionary actions or fears. PMID:15496256

SAR antenna design for ambiguity and multipath suppression

DEFF Research Database (Denmark)

Christensen, Erik Lintz; Dich, Mikael

1993-01-01

A high resolution airborne synthetic aperture radar (SAR) has been developed at the Electromagnetics Institute (EMI) for remote sensing applications. The paper considers the radiation of antennas for a SAR system from a systems perspective. The basic specifications of an idealised antenna...... are obtained from the required swath and the azimuth footprint needed for the SAR processing. The radiation from a real antenna causes unwanted signal returns that lead to intensity variations (multipath) and ghost echoes (ambiguity). Additional specifications are deduced by considering these signals...

77 FR 58818 - Notice of Proposed Information Collection Requests; Federal Student Aid; William D. Ford Federal...

Science.gov (United States)

2012-09-24

... DEPARTMENT OF EDUCATION Notice of Proposed Information Collection Requests; Federal Student Aid; William D. Ford Federal Direct Loan Program Regulations-- Servicemembers Civil Relief Act SUMMARY: Upon a... in response to this notice will be considered public records. Title of Collection: William D. Ford...

Bats and SARS

Centers for Disease Control (CDC) Podcasts

Bats are a natural reservoir for emerging viruses, among them henipaviruses and rabies virus variants. Dr. Nina Marano, Chief, Geographic Medicine and Health Promotion Branch, Division of Global Migration and Quarantine, CDC, explains connection between horseshoe bats and SARS coronavirus transmission.

Research on Airborne SAR Imaging Based on Esc Algorithm

Science.gov (United States)

Dong, X. T.; Yue, X. J.; Zhao, Y. H.; Han, C. M.

2017-09-01

Due to the ability of flexible, accurate, and fast obtaining abundant information, airborne SAR is significant in the field of Earth Observation and many other applications. Optimally the flight paths are straight lines, but in reality it is not the case since some portion of deviation from the ideal path is impossible to avoid. A small disturbance from the ideal line will have a major effect on the signal phase, dramatically deteriorating the quality of SAR images and data. Therefore, to get accurate echo information and radar images, it is essential to measure and compensate for nonlinear motion of antenna trajectories. By means of compensating each flying trajectory to its reference track, MOCO method corrects linear phase error and quadratic phase error caused by nonlinear antenna trajectories. Position and Orientation System (POS) data is applied to acquiring accuracy motion attitudes and spatial positions of antenna phase centre (APC). In this paper, extend chirp scaling algorithm (ECS) is used to deal with echo data of airborne SAR. An experiment is done using VV-Polarization raw data of C-band airborne SAR. The quality evaluations of compensated SAR images and uncompensated SAR images are done in the experiment. The former always performs better than the latter. After MOCO processing, azimuth ambiguity is declined, peak side lobe ratio (PSLR) effectively improves and the resolution of images is improved obviously. The result shows the validity and operability of the imaging process for airborne SAR.

RESEARCH ON AIRBORNE SAR IMAGING BASED ON ESC ALGORITHM

Directory of Open Access Journals (Sweden)

X. T. Dong

2017-09-01

Full Text Available Due to the ability of flexible, accurate, and fast obtaining abundant information, airborne SAR is significant in the field of Earth Observation and many other applications. Optimally the flight paths are straight lines, but in reality it is not the case since some portion of deviation from the ideal path is impossible to avoid. A small disturbance from the ideal line will have a major effect on the signal phase, dramatically deteriorating the quality of SAR images and data. Therefore, to get accurate echo information and radar images, it is essential to measure and compensate for nonlinear motion of antenna trajectories. By means of compensating each flying trajectory to its reference track, MOCO method corrects linear phase error and quadratic phase error caused by nonlinear antenna trajectories. Position and Orientation System (POS data is applied to acquiring accuracy motion attitudes and spatial positions of antenna phase centre (APC. In this paper, extend chirp scaling algorithm (ECS is used to deal with echo data of airborne SAR. An experiment is done using VV-Polarization raw data of C-band airborne SAR. The quality evaluations of compensated SAR images and uncompensated SAR images are done in the experiment. The former always performs better than the latter. After MOCO processing, azimuth ambiguity is declined, peak side lobe ratio (PSLR effectively improves and the resolution of images is improved obviously. The result shows the validity and operability of the imaging process for airborne SAR.

Applications of SAR Interferometry in Earth and Environmental Science Research

Science.gov (United States)

Zhou, Xiaobing; Chang, Ni-Bin; Li, Shusun

2009-01-01

This paper provides a review of the progress in regard to the InSAR remote sensing technique and its applications in earth and environmental sciences, especially in the past decade. Basic principles, factors, limits, InSAR sensors, available software packages for the generation of InSAR interferograms were summarized to support future applications. Emphasis was placed on the applications of InSAR in seismology, volcanology, land subsidence/uplift, landslide, glaciology, hydrology, and forestry sciences. It ends with a discussion of future research directions. PMID:22573992

Applications of SAR Interferometry in Earth and Environmental Science Research

Directory of Open Access Journals (Sweden)

Xiaobing Zhou

2009-03-01

Full Text Available This paper provides a review of the progress in regard to the InSAR remote sensing technique and its applications in earth and environmental sciences, especially in the past decade. Basic principles, factors, limits, InSAR sensors, available software packages for the generation of InSAR interferograms were summarized to support future applications. Emphasis was placed on the applications of InSAR in seismology, volcanology, land subsidence/uplift, landslide, glaciology, hydrology, and forestry sciences. It ends with a discussion of future research directions.

Evaluation of the Wishart test statistics for polarimetric SAR data

DEFF Research Database (Denmark)

Skriver, Henning; Nielsen, Allan Aasbjerg; Conradsen, Knut

2003-01-01

A test statistic for equality of two covariance matrices following the complex Wishart distribution has previously been used in new algorithms for change detection, edge detection and segmentation in polarimetric SAR images. Previously, the results for change detection and edge detection have been...... quantitatively evaluated. This paper deals with the evaluation of segmentation. A segmentation performance measure originally developed for single-channel SAR images has been extended to polarimetric SAR images, and used to evaluate segmentation for a merge-using-moment algorithm for polarimetric SAR data....

Mapping Regional Inundation with Spaceborne L-Band SAR

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Bruce Chapman

2015-04-01

Full Text Available Shortly after the launch of ALOS PALSAR L-band SAR by the Japan Space Exploration Agency (JAXA, a program to develop an Earth Science Data Record (ESDR for inundated wetlands was funded by NASA. Using established methodologies, extensive multi-temporal L-band ALOS ScanSAR data acquired bi-monthly by the PALSAR instrument onboard ALOS were used to classify the inundation state for South America for delivery as a component of this Inundated Wetlands ESDR (IW-ESDR and in collaboration with JAXA’s ALOS Kyoto and Carbon Initiative science programme. We describe these methodologies and the final classification of the inundation state, then compared this with results derived from dual-season data acquired by the JERS-1 L-band SAR mission in 1995 and 1996, as well as with estimates of surface water extent measured globally every 10 days by coarser resolution sensors. Good correspondence was found when comparing open water extent classified from multi-temporal ALOS ScanSAR data with surface water fraction identified from coarse resolution sensors, except in those regions where there may be differences in sensitivity to widespread and shallow seasonal flooding event, or in areas that could be excluded through use of a continental-scale inundatable mask. It was found that the ALOS ScanSAR classification of inundated vegetation was relatively insensitive to inundated herbaceous vegetation. Inundation dynamics were examined using the multi-temporal ALOS ScanSAR acquisitions over the Pacaya-Samiria and surrounding areas in the Peruvian Amazon.

New challenges for a SAR toolbox

International Nuclear Information System (INIS)

Loreaux, P.; Quin, G.

2013-01-01

High resolution multi-frequency synthetic aperture radar (SAR) imagery, available since early 2008, brings all weather capability and day/night operability in support of safeguards verification. Today, a combined approach of high resolution optical and radar imagery in monitoring exercise would enable looking at any area of interest on daily basis. One of the challenges is the co-registration of SAR images acquired with different acquisition mode and also with different optical images. We show in this paper the on-going research work to find a general co-register method and an automatic tool to detect changes. Before having an operational co-register tool, a method to find automatically tie points between SAR images acquired with different acquisition mode and with optical images has to be developed. Concerning an automatic change detection method we can conclude that the study of the Harmonic mean, Geometric mean and Arithmetic mean, enables several applications like change detection for SAR imagery. Thus, we developed the MAGMA (Method for Arithmetic and Geometric Means Analysis) change detection method. As shown in this paper, the MAGMA method improves the Maximum Likelihood techniques like GLRT, using Information-Theory concepts to detect changes between SAR amplitude images. The major improvement consists in a lower false detection rate, especially in low amplitude areas. The second improvement consists in a better location of the changes in clearly delimited areas, which enables precise interpretations. Results presented here reveal the potential of high resolution radar imagery for a baseline description of some sites, change detection based on repeat pass imagery acquisitions and site specific constraints in coherent change detection due to cover conditions. (A.C.)

Detection of macroalgae blooms by complex SAR imagery

International Nuclear Information System (INIS)

Shen, Hui; Perrie, William; Liu, Qingrong; He, Yijun

2014-01-01

Highlights: • Complex SAR imagery enables better recognition of macroalgae patches. • Combination of different information in SAR matrix forms new index factors. • Proposed index factors contribute to unsupervised recognition of macroalgae. -- Abstract: Increased frequency and enhanced damage to the marine environment and to human society caused by green macroalgae blooms demand improved high-resolution early detection methods. Conventional satellite remote sensing methods via spectra radiometers do not work in cloud-covered areas, and therefore cannot meet these demands for operational applications. We present a methodology for green macroalgae bloom detection based on RADARSAT-2 synthetic aperture radar (SAR) images. Green macroalgae patches exhibit different polarimetric characteristics compared to the open ocean surface, in both the amplitude and phase domains of SAR-measured complex radar backscatter returns. In this study, new index factors are defined which have opposite signs in green macroalgae-covered areas, compared to the open water surface. These index factors enable unsupervised detection from SAR images, providing a high-resolution new tool for detection of green macroalgae blooms, which can potentially contribute to a better understanding of the mechanisms related to outbreaks of green macroalgae blooms in coastal areas throughout the world ocean

Wavelet Filter Banks for Super-Resolution SAR Imaging

Science.gov (United States)

Sheybani, Ehsan O.; Deshpande, Manohar; Memarsadeghi, Nargess

2011-01-01

This paper discusses Innovative wavelet-based filter banks designed to enhance the analysis of super resolution Synthetic Aperture Radar (SAR) images using parametric spectral methods and signal classification algorithms, SAR finds applications In many of NASA's earth science fields such as deformation, ecosystem structure, and dynamics of Ice, snow and cold land processes, and surface water and ocean topography. Traditionally, standard methods such as Fast-Fourier Transform (FFT) and Inverse Fast-Fourier Transform (IFFT) have been used to extract Images from SAR radar data, Due to non-parametric features of these methods and their resolution limitations and observation time dependence, use of spectral estimation and signal pre- and post-processing techniques based on wavelets to process SAR radar data has been proposed. Multi-resolution wavelet transforms and advanced spectral estimation techniques have proven to offer efficient solutions to this problem.

The economic impact of SARS in Beijing, China.

Science.gov (United States)

Beutels, Philippe; Jia, Na; Zhou, Qing-Yi; Smith, Richard; Cao, Wu-Chun; de Vlas, Sake J

2009-11-01

To document the impact of the severe acute respiratory syndrome (SARS) outbreak in Beijing on indicators of social and economic activity. Associations between time series of daily and monthly SARS cases and deaths and volume of public train, airplane and cargo transport, tourism, household consumption patterns and gross domestic product growth in Beijing were investigated using the cross-correlation function. Significant correlation coefficients were found for all indicators except wholesale accounts and expenditures on necessities, with the most significant correlations occurring with a delay of 1 day to 1 month. Especially leisure activities, local and international transport and tourism were affected by SARS particularly in May 2003. Much of this consumption was merely postponed; but irrecoverable losses to the tourist sector alone were estimated at about US$ 1.4 bn, or 300 times the cost of treatment for SARS cases in Beijing.

INVENTORY OF IRRIGATED RICE ECOSYSTEM USING POLARIMETRIC SAR DATA

Directory of Open Access Journals (Sweden)

P. Srikanth

2012-08-01

Full Text Available An attempt has been made in the current study to assess the potential of polarimetric SAR data for inventory of kharif rice and the major competing crop like cotton. In the process, physical process of the scattering mechanisms occurring in rice and cotton crops at different phonological stages was studied through the use of temporal Radarsat 2 Fine quadpol SAR data. The temporal dynamics of the volume, double and odd bounce, entropy, anisotropy, alpha parameters and polarimertic signatures, classification through isodata clustering and Wishart techniques were assessed. The Wishart (H-a classification showed higher overall as well as rice and cotton crop accuracies compared to the isodata clustering from Freeman 3-component decomposition. The classification of temporal SAR data sets independently showed that the rice crop forecasting can be advanced with the use of appropriate single date polarimetric SAR data rather than using temporal SAR amplitude data sets with the single polarization in irrigated rice ecosystems

Guided SAR image despeckling with probabilistic non local weights

Science.gov (United States)

Gokul, Jithin; Nair, Madhu S.; Rajan, Jeny

2017-12-01

SAR images are generally corrupted by granular disturbances called speckle, which makes visual analysis and detail extraction a difficult task. Non Local despeckling techniques with probabilistic similarity has been a recent trend in SAR despeckling. To achieve effective speckle suppression without compromising detail preservation, we propose an improvement for the existing Generalized Guided Filter with Bayesian Non-Local Means (GGF-BNLM) method. The proposed method (Guided SAR Image Despeckling with Probabilistic Non Local Weights) replaces parametric constants based on heuristics in GGF-BNLM method with dynamically derived values based on the image statistics for weight computation. Proposed changes make GGF-BNLM method adaptive and as a result, significant improvement is achieved in terms of performance. Experimental analysis on SAR images shows excellent speckle reduction without compromising feature preservation when compared to GGF-BNLM method. Results are also compared with other state-of-the-art and classic SAR depseckling techniques to demonstrate the effectiveness of the proposed method.

Prototype Theory Based Feature Representation for PolSAR Images

OpenAIRE

Huang Xiaojing; Yang Xiangli; Huang Pingping; Yang Wen

2016-01-01

This study presents a new feature representation approach for Polarimetric Synthetic Aperture Radar (PolSAR) image based on prototype theory. First, multiple prototype sets are generated using prototype theory. Then, regularized logistic regression is used to predict similarities between a test sample and each prototype set. Finally, the PolSAR image feature representation is obtained by ensemble projection. Experimental results of an unsupervised classification of PolSAR images show that our...

One carbon metabolism in SAR11 pelagic marine bacteria.

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Jing Sun

Full Text Available The SAR11 Alphaproteobacteria are the most abundant heterotrophs in the oceans and are believed to play a major role in mineralizing marine dissolved organic carbon. Their genomes are among the smallest known for free-living heterotrophic cells, raising questions about how they successfully utilize complex organic matter with a limited metabolic repertoire. Here we show that conserved genes in SAR11 subgroup Ia (Candidatus Pelagibacter ubique genomes encode pathways for the oxidation of a variety of one-carbon compounds and methyl functional groups from methylated compounds. These pathways were predicted to produce energy by tetrahydrofolate (THF-mediated oxidation, but not to support the net assimilation of biomass from C1 compounds. Measurements of cellular ATP content and the oxidation of (14C-labeled compounds to (14CO(2 indicated that methanol, formaldehyde, methylamine, and methyl groups from glycine betaine (GBT, trimethylamine (TMA, trimethylamine N-oxide (TMAO, and dimethylsulfoniopropionate (DMSP were oxidized by axenic cultures of the SAR11 strain Ca. P. ubique HTCC1062. Analyses of metagenomic data showed that genes for C1 metabolism occur at a high frequency in natural SAR11 populations. In short term incubations, natural communities of Sargasso Sea microbial plankton expressed a potential for the oxidation of (14C-labeled formate, formaldehyde, methanol and TMAO that was similar to cultured SAR11 cells and, like cultured SAR11 cells, incorporated a much larger percentage of pyruvate and glucose (27-35% than of C1 compounds (2-6% into biomass. Collectively, these genomic, cellular and environmental data show a surprising capacity for demethylation and C1 oxidation in SAR11 cultures and in natural microbial communities dominated by SAR11, and support the conclusion that C1 oxidation might be a significant conduit by which dissolved organic carbon is recycled to CO(2 in the upper ocean.

Mapping and monitoring renewable resources with space SAR

Science.gov (United States)

Ulaby, F. T.; Brisco, B.; Dobson, M. C.; Moezzi, S.

1983-01-01

The SEASAT-A SAR and SIR-A imagery was examined to evaluate the quality and type of information that can be extracted and used to monitor renewable resources on Earth. Two tasks were carried out: (1) a land cover classification study which utilized two sets of imagery acquired by the SEASAT-A SAR, one set by SIR-A, and one LANDSAT set (4 bands); and (2) a change detection to examine differences between pairs of SEASAT-A SAR images and relates them to hydrologic and/or agronomic variations in the scene.

Peer-led versus teacher-led AIDS education for female high-school students in Yazd, Islamic Republic of Iran.

Science.gov (United States)

Baghianimoghadam, M H; Forghani, H; Zolghadr, R; Rahaei, Z; Khani, P

2012-04-01

Peer-led programmes on AIDS prevention have shown a good level of effectiveness when tested among high-risk populations. This study compared peer-led and teacher-led methods of education about HIV/AIDS among female high-school students in Yazd city, Islamic Republic of Iran. In 2009 students in 3 high schools were trained by their classmates (peer-led), by the research team (teacher-led) or had no education (controls); 180 students completed a specially designed questionnaire based on the health belief model, before and after the intervention. Post-intervention mean knowledge scores increased 2-fold in the peer-led group, and this was significantly higher than the increase in the teacher-led group scores (1.5-fold). Control group scores were unchanged. In the peer-led programme all of the components of the model were significantly improved whereas in the teacher-led programme, only perceived severity and perceived barriers scored significantly higher after the intervention.

AWARENESS, KNOWLEDGE, AND BEHAVIOR REGARDING HIV/AIDS AMONG FRESHMAN STUDENTS AT OAKLAND UNIVERSITY

Directory of Open Access Journals (Sweden)

Sean Mackman

2017-05-01

Full Text Available Human immunodeficiency virus (HIV causes a sexually transmitted disease (STD affecting the human immune system. It is mainly transmitted through sexual intercourse, blood transfusions, hypodermic needles, and parenterally. Multiple actions can be taken to prevent the spread of HIV/AIDS, such as condom and sterile needle use and HIV testing for pregnant women. This study aims to assess freshmen students’ awareness, knowledge, attitudes, and behavioral perceptions regarding HIV/AIDS at Oakland University (OU in Michigan. This study is a cross-sectional survey targeting freshman students at OU. The questionnaire is comprised of seven sections including demographics, risk perception, protection measures, alcohol tendencies, health-seeking behaviors, culturally sensitive issues, and methods of dissemination of information. The mean age of respondents was 20. The majority of respondents knew that HIV is transmitted sexually (98% and by sharing needles (98%. Many misconceptions about transmission of HIV were expressed by 53%. Data showed that while there was good knowledge regarding HIV transmission and prevention, some misconceptions still prevailed. Our results indicate the need to develop educational programs with specific interventions to raise awareness about preventive measures, clear misconceptions, and promote healthy lifestyle in order to prevent new HIV infections among young college students.

Comparison of SAR calculation algorithms for the finite-difference time-domain method

International Nuclear Information System (INIS)

Laakso, Ilkka; Uusitupa, Tero; Ilvonen, Sami

2010-01-01

Finite-difference time-domain (FDTD) simulations of specific-absorption rate (SAR) have several uncertainty factors. For example, significantly varying SAR values may result from the use of different algorithms for determining the SAR from the FDTD electric field. The objective of this paper is to rigorously study the divergence of SAR values due to different SAR calculation algorithms and to examine if some SAR calculation algorithm should be preferred over others. For this purpose, numerical FDTD results are compared to analytical solutions in a one-dimensional layered model and a three-dimensional spherical object. Additionally, the implications of SAR calculation algorithms for dosimetry of anatomically realistic whole-body models are studied. The results show that the trapezium algorithm-based on the trapezium integration rule-is always conservative compared to the analytic solution, making it a good choice for worst-case exposure assessment. In contrast, the mid-ordinate algorithm-named after the mid-ordinate integration rule-usually underestimates the analytic SAR. The linear algorithm-which is approximately a weighted average of the two-seems to be the most accurate choice overall, typically giving the best fit with the shape of the analytic SAR distribution. For anatomically realistic models, the whole-body SAR difference between different algorithms is relatively independent of the used body model, incident direction and polarization of the plane wave. The main factors affecting the difference are cell size and frequency. The choice of the SAR calculation algorithm is an important simulation parameter in high-frequency FDTD SAR calculations, and it should be explained to allow intercomparison of the results between different studies. (note)

Evidence of rock slope breathing using ground-based InSAR

Science.gov (United States)

Rouyet, Line; Kristensen, Lene; Derron, Marc-Henri; Michoud, Clément; Blikra, Lars Harald; Jaboyedoff, Michel; Lauknes, Tom Rune

2017-07-01

Ground-Based Interferometric Synthetic Aperture Radar (GB-InSAR) campaigns were performed in summer 2011 and 2012 in the Romsdalen valley (Møre & Romsdal county, western Norway) in order to assess displacements on Mannen/Børa rock slope. Located 1 km northwest, a second GB-InSAR system continuously monitors the large Mannen rockslide. The availability of two GB-InSAR positions creates a wide coverage of the rock slope, including a slight dataset overlap valuable for validation. A phenomenon of rock slope breathing is detected in a remote and hard-to-access area in mid-slope. Millimetric upward displacements are recorded in August 2011. Analysis of 2012 GB-InSAR campaign, combined with the large dataset from the continuous station, shows that the slope is affected by inflation/deflation phenomenon between 5 and 10 mm along the line-of-sight. The pattern is not homogenous in time and inversions of movement have a seasonal recurrence. These seasonal changes are confirmed by satellite InSAR observations and can possibly be caused by hydrogeological variations. In addition, combination of GB-InSAR results, in situ measurements and satellite InSAR analyses contributes to a better overview of movement distribution over the whole area.

Global Rapid Flood Mapping System with Spaceborne SAR Data

Science.gov (United States)

Yun, S. H.; Owen, S. E.; Hua, H.; Agram, P. S.; Fattahi, H.; Liang, C.; Manipon, G.; Fielding, E. J.; Rosen, P. A.; Webb, F.; Simons, M.

2017-12-01

As part of the Advanced Rapid Imaging and Analysis (ARIA) project for Natural Hazards, at NASA's Jet Propulsion Laboratory and California Institute of Technology, we have developed an automated system that produces derived products for flood extent map generation using spaceborne SAR data. The system takes user's input of area of interest polygons and time window for SAR data search (pre- and post-event). Then the system automatically searches and downloads SAR data, processes them to produce coregistered SAR image pairs, and generates log amplitude ratio images from each pair. Currently the system is automated to support SAR data from the European Space Agency's Sentinel-1A/B satellites. We have used the system to produce flood extent maps from Sentinel-1 SAR data for the May 2017 Sri Lanka floods, which killed more than 200 people and displaced about 600,000 people. Our flood extent maps were delivered to the Red Cross to support response efforts. Earlier we also responded to the historic August 2016 Louisiana floods in the United States, which claimed 13 people's lives and caused over $10 billion property damage. For this event, we made synchronized observations from space, air, and ground in close collaboration with USGS and NOAA. The USGS field crews acquired ground observation data, and NOAA acquired high-resolution airborne optical imagery within the time window of +/-2 hours of the SAR data acquisition by JAXA's ALOS-2 satellite. The USGS coordinates of flood water boundaries were used to calibrate our flood extent map derived from the ALOS-2 SAR data, and the map was delivered to FEMA for estimating the number of households affected. Based on the lessons learned from this response effort, we customized the ARIA system automation for rapid flood mapping and developed a mobile friendly web app that can easily be used in the field for data collection. Rapid automatic generation of SAR-based global flood maps calibrated with independent observations from

Analysis of Spatiotemporal Characteristics of Pandemic SARS Spread in Mainland China.

Science.gov (United States)

Cao, Chunxiang; Chen, Wei; Zheng, Sheng; Zhao, Jian; Wang, Jinfeng; Cao, Wuchun

2016-01-01

Severe acute respiratory syndrome (SARS) is one of the most severe emerging infectious diseases of the 21st century so far. SARS caused a pandemic that spread throughout mainland China for 7 months, infecting 5318 persons in 194 administrative regions. Using detailed mainland China epidemiological data, we study spatiotemporal aspects of this person-to-person contagious disease and simulate its spatiotemporal transmission dynamics via the Bayesian Maximum Entropy (BME) method. The BME reveals that SARS outbreaks show autocorrelation within certain spatial and temporal distances. We use BME to fit a theoretical covariance model that has a sine hole spatial component and exponential temporal component and obtain the weights of geographical and temporal autocorrelation factors. Using the covariance model, SARS dynamics were estimated and simulated under the most probable conditions. Our study suggests that SARS transmission varies in its epidemiological characteristics and SARS outbreak distributions exhibit palpable clusters on both spatial and temporal scales. In addition, the BME modelling demonstrates that SARS transmission features are affected by spatial heterogeneity, so we analyze potential causes. This may benefit epidemiological control of pandemic infectious diseases.

Hydrodynamics of the groundwater-fed Sian Ka'an Wetlands, Mexico, From InSAR and SAR Data

DEFF Research Database (Denmark)

Gondwe, Bibi Ruth Neuman; Hong, S.; Wdowinski, S.

2008-01-01

The 5300 km2 pristine Sian Ka'an wetland in Mexico is fed entirely by groundwater from the karst aquifer of the Yucatan Peninsula. The area is undeveloped and hence difficult to access. The inflow through underground rivers and karst structures is hard to observe resulting in difficulties......-changes of the backscattered radar signal, which can be related to the water level changes in vegetated wetlands. SAR data reveals information of surface properties such as the degree of flooding through the amplitude of the backscattered signal. We used RADARSAT-1 InSAR and SAR data to form 36 interferograms and 13 flooding...... maps with 24 to 48 day intervals covering the time span of October 2006 to March 2008. The dataset has a high spatial resolution of ca. 20 to 60 m. Sian Ka'an consists of a mosaic of freshwater sloughs, canals, floodplains and brackish tidally-influenced areas. Throughout most of the year, water level...

AIDS prevention and college students: male and female responses to "fear-provoking" messages.

Science.gov (United States)

Johnson, K; LaTour, M S

1991-01-01

This study was designed to examine the effects of fear appeals in AIDS prevention messages and to determine whether or not males and females differ in their response to these appeals. MANOVA results from a sample of 179 junior and senior business students at a mid-Atlantic urban university indicate that significant differences in message effects were associated with type of appeal, gender of the respondent, and the interaction between appeal and gender.

Methodology of dose calculation for the SRS SAR

International Nuclear Information System (INIS)

Price, J.B.

1991-07-01

The Savannah River Site (SRS) Safety Analysis Report (SAR) covering K reactor operation assesses a spectrum of design basis accidents. The assessment includes estimation of the dose consequences from the analyzed accidents. This report discusses the methodology used to perform the dose analysis reported in the SAR and also includes the quantified doses. Doses resulting from postulated design basis reactor accidents in Chapter 15 of the SAR are discussed, as well as an accident in which three percent of the fuel melts. Doses are reported for both atmospheric and aqueous releases. The methodology used to calculate doses from these accidents as reported in the SAR is consistent with NRC guidelines and industry standards. The doses from the design basis accidents for the SRS reactors are below the limits set for commercial reactors by the NRC and also meet industry criteria. A summary of doses for various postulated accidents is provided

Towards Building a Computer Aided Education System for Special Students Using Wearable Sensor Technologies

Directory of Open Access Journals (Sweden)

Raja Majid Mehmood

2017-02-01

Full Text Available Human computer interaction is a growing field in terms of helping people in their daily life to improve their living. Especially, people with some disability may need an interface which is more appropriate and compatible with their needs. Our research is focused on similar kinds of problems, such as students with some mental disorder or mood disruption problems. To improve their learning process, an intelligent emotion recognition system is essential which has an ability to recognize the current emotional state of the brain. Nowadays, in special schools, instructors are commonly use some conventional methods for managing special students for educational purposes. In this paper, we proposed a novel computer aided method for instructors at special schools where they can teach special students with the support of our system using wearable technologies.

Empirical wind retrieval model based on SAR spectrum measurements

Science.gov (United States)

Panfilova, Maria; Karaev, Vladimir; Balandina, Galina; Kanevsky, Mikhail; Portabella, Marcos; Stoffelen, Ad

The present paper considers polarimetric SAR wind vector applications. Remote-sensing measurements of the near-surface wind over the ocean are of great importance for the understanding of atmosphere-ocean interaction. In recent years investigations for wind vector retrieval using Synthetic Aperture Radar (SAR) data have been performed. In contrast with scatterometers, a SAR has a finer spatial resolution that makes it a more suitable microwave instrument to explore wind conditions in the marginal ice zones, coastal regions and lakes. The wind speed retrieval procedure from scatterometer data matches the measured radar backscattering signal with the geophysical model function (GMF). The GMF determines the radar cross section dependence on the wind speed and direction with respect to the azimuthal angle of the radar beam. Scatterometers provide information on wind speed and direction simultaneously due to the fact that each wind vector cell (WVC) is observed at several azimuth angles. However, SAR is not designed to be used as a high resolution scatterometer. In this case, each WVC is observed at only one single azimuth angle. That is why for wind vector determination additional information such as wind streak orientation over the sea surface is required. It is shown that the wind vector can be obtained using polarimetric SAR without additional information. The main idea is to analyze the spectrum of a homogeneous SAR image area instead of the backscattering normalized radar cross section. Preliminary numerical simulations revealed that SAR image spectral maxima positions depend on the wind vector. Thus the following method for wind speed retrieval is proposed. In the first stage of the algorithm, the SAR spectrum maxima are determined. This procedure is carried out to estimate the wind speed and direction with ambiguities separated by 180 degrees due to the SAR spectrum symmetry. The second stage of the algorithm allows us to select the correct wind direction

Retention of first aid and basic life support skills in undergraduate medical students

Directory of Open Access Journals (Sweden)

Pim A. de Ruijter

2014-11-01

Full Text Available Background: Undergraduate medical students follow a compulsory first aid (FA and basic life support (BLS course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in undergraduate medical students. Methods: One hundred and twenty students were randomly selected from first year (n=349 medical students who successfully followed a compulsory FA and BLS course. From these 120 students, 94 (78% and 69 (58% participated in retention tests of FA and BLS skills after 1 and 2 years, respectively. The assessment consisted of two FA stations and one BLS station. Results: After 1 year, only 2% passed both FA and BLS stations and 68% failed both FA and BLS stations. After 2 years, 5% passed and 50% failed both FA and BLS stations. Despite the high failure rate at the stations, 90% adequately checked vital signs and started cardiopulmonary resuscitation appropriately. Conclusions: The long-term retention of FA and BLS skills after a compulsory course in the first year is poor. Adequate check of vital signs and commencing cardiopulmonary resuscitation retained longer.

Retention of first aid and basic life support skills in undergraduate medical students.

Science.gov (United States)

de Ruijter, Pim A; Biersteker, Heleen A; Biert, Jan; van Goor, Harry; Tan, Edward C

2014-01-01

Undergraduate medical students follow a compulsory first aid (FA) and basic life support (BLS) course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in undergraduate medical students. One hundred and twenty students were randomly selected from first year (n=349) medical students who successfully followed a compulsory FA and BLS course. From these 120 students, 94 (78%) and 69 (58%) participated in retention tests of FA and BLS skills after 1 and 2 years, respectively. The assessment consisted of two FA stations and one BLS station. After 1 year, only 2% passed both FA and BLS stations and 68% failed both FA and BLS stations. After 2 years, 5% passed and 50% failed both FA and BLS stations. Despite the high failure rate at the stations, 90% adequately checked vital signs and started cardiopulmonary resuscitation appropriately. The long-term retention of FA and BLS skills after a compulsory course in the first year is poor. Adequate check of vital signs and commencing cardiopulmonary resuscitation retained longer.

The Need for Organizational Integration in Financial Aid Administration.

Science.gov (United States)

Fischer, Mary L.

1986-01-01

Because of the integral relationship of student financial aid with student recruitment and retention, budgeting, program design and development, student services, and long-range institutional planning, it is useful to review organizational structure periodically to ensure visibility of the financial aid function within the institution. (MSE)

Demonstrator for Automatic Target Classification in SAR Imagery

NARCIS (Netherlands)

Wit, J.J.M. de; Broek, A.C. van den; Dekker, R.J.

2006-01-01

Due to the increasing use of unmanned aerial vehicles (UAV) for reconnaissance, surveillance, and target acquisition applications, the interest in synthetic aperture radar (SAR) systems is growing. In order to facilitate the processing of the enormous amount of SAR data on the ground, automatic

SAR image effects on coherence and coherence estimation.

Energy Technology Data Exchange (ETDEWEB)

Bickel, Douglas Lloyd

2014-01-01

Radar coherence is an important concept for imaging radar systems such as synthetic aperture radar (SAR). This document quantifies some of the effects in SAR which modify the coherence. Although these effects can disrupt the coherence within a single SAR image, this report will focus on the coherence between separate images, such as for coherent change detection (CCD) processing. There have been other presentations on aspects of this material in the past. The intent of this report is to bring various issues that affect the coherence together in a single report to support radar engineers in making decisions about these matters.

Phase correction and error estimation in InSAR time series analysis

Science.gov (United States)

Zhang, Y.; Fattahi, H.; Amelung, F.

2017-12-01

During the last decade several InSAR time series approaches have been developed in response to the non-idea acquisition strategy of SAR satellites, such as large spatial and temporal baseline with non-regular acquisitions. The small baseline tubes and regular acquisitions of new SAR satellites such as Sentinel-1 allows us to form fully connected networks of interferograms and simplifies the time series analysis into a weighted least square inversion of an over-determined system. Such robust inversion allows us to focus more on the understanding of different components in InSAR time-series and its uncertainties. We present an open-source python-based package for InSAR time series analysis, called PySAR (https://yunjunz.github.io/PySAR/), with unique functionalities for obtaining unbiased ground displacement time-series, geometrical and atmospheric correction of InSAR data and quantifying the InSAR uncertainty. Our implemented strategy contains several features including: 1) improved spatial coverage using coherence-based network of interferograms, 2) unwrapping error correction using phase closure or bridging, 3) tropospheric delay correction using weather models and empirical approaches, 4) DEM error correction, 5) optimal selection of reference date and automatic outlier detection, 6) InSAR uncertainty due to the residual tropospheric delay, decorrelation and residual DEM error, and 7) variance-covariance matrix of final products for geodetic inversion. We demonstrate the performance using SAR datasets acquired by Cosmo-Skymed and TerraSAR-X, Sentinel-1 and ALOS/ALOS-2, with application on the highly non-linear volcanic deformation in Japan and Ecuador (figure 1). Our result shows precursory deformation before the 2015 eruptions of Cotopaxi volcano, with a maximum uplift of 3.4 cm on the western flank (fig. 1b), with a standard deviation of 0.9 cm (fig. 1a), supporting the finding by Morales-Rivera et al. (2017, GRL); and a post-eruptive subsidence on the same

Fast Superpixel Segmentation Algorithm for PolSAR Images

Directory of Open Access Journals (Sweden)

Zhang Yue

2017-10-01

Full Text Available As a pre-processing technique, superpixel segmentation algorithms should be of high computational efficiency, accurate boundary adherence and regular shape in homogeneous regions. A fast superpixel segmentation algorithm based on Iterative Edge Refinement (IER has shown to be applicable on optical images. However, it is difficult to obtain the ideal results when IER is applied directly to PolSAR images due to the speckle noise and small or slim regions in PolSAR images. To address these problems, in this study, the unstable pixel set is initialized as all the pixels in the PolSAR image instead of the initial grid edge pixels. In the local relabeling of the unstable pixels, the fast revised Wishart distance is utilized instead of the Euclidean distance in CIELAB color space. Then, a post-processing procedure based on dissimilarity measure is empolyed to remove isolated small superpixels as well as to retain the strong point targets. Finally, extensive experiments based on a simulated image and a real-world PolSAR image from Airborne Synthetic Aperture Radar (AirSAR are conducted, showing that the proposed algorithm, compared with three state-of-the-art methods, performs better in terms of several commonly used evaluation criteria with high computational efficiency, accurate boundary adherence, and homogeneous regularity.

Program Merges SAR Data on Terrain and Vegetation Heights

Science.gov (United States)

Siqueira, Paul; Hensley, Scott; Rodriguez, Ernesto; Simard, Marc

2007-01-01

X/P Merge is a computer program that estimates ground-surface elevations and vegetation heights from multiple sets of data acquired by the GeoSAR instrument [a terrain-mapping synthetic-aperture radar (SAR) system that operates in the X and bands]. X/P Merge software combines data from X- and P-band digital elevation models, SAR backscatter magnitudes, and interferometric correlation magnitudes into a simplified set of output topographical maps of ground-surface elevation and tree height.

The Danish (Q)SAR Database Update Project

DEFF Research Database (Denmark)

Nikolov, Nikolai Georgiev; Dybdahl, Marianne; Abildgaard Rosenberg, Sine

2013-01-01

The Danish (Q)SAR Database is a collection of predictions from quantitative structure–activity relationship ((Q)SAR) models for over 70 environmental and human health-related endpoints (covering biodegradation, metabolism, allergy, irritation, endocrine disruption, teratogenicity, mutagenicity......, carcinogenicity and others), each of them available for 185,000 organic substances. The database has been available online since 2005 (http://qsar.food.dtu.dk). A major update project for the Danish (Q)SAR database is under way, with a new online release planned in the beginning of 2015. The updated version...... will contain more than 600,000 discrete organic structures and new, more precise predictions for all endpoints, derived by consensus algorithms from a number of state-of-the-art individual predictions. Copyright © 2013 Published by Elsevier Ireland Ltd....

First Image Products from EcoSAR - Osa Peninsula, Costa Rica

Science.gov (United States)

Osmanoglu, Batuhan; Lee, SeungKuk; Rincon, Rafael; Fatuyinbo, Lola; Bollian, Tobias; Ranson, Jon

2016-01-01

Designed especially for forest ecosystem studies, EcoSAR employs state-of-the-art digital beamforming technology to generate wide-swath, high-resolution imagery. EcoSARs dual antenna single-pass imaging capability eliminates temporal decorrelation from polarimetric and interferometric analysis, increasing the signal strength and simplifying models used to invert forest structure parameters. Antennae are physically separated by 25 meters providing single pass interferometry. In this mode the radar is most sensitive to topography. With 32 active transmit and receive channels, EcoSARs digital beamforming is an order of magnitude more versatile than the digital beamforming employed on the upcoming NISAR mission. EcoSARs long wavelength (P-band, 435 MHz, 69 cm) measurements can be used to simulate data products for ESAs future BIOMASS mission, allowing scientists to develop algorithms before the launch of the satellite. EcoSAR can also be deployed to collect much needed data where BIOMASS satellite wont be allowed to collect data (North America, Europe and Arctic), filling in the gaps to keep a watchful eye on the global carbon cycle. EcoSAR can play a vital role in monitoring, reporting and verification schemes of internationals programs such as UN-REDD (United Nations Reducing Emissions from Deforestation and Degradation) benefiting global society. EcoSAR was developed and flown with support from NASA Earth Sciences Technology Offices Instrument Incubator Program.

Research on the method of extracting DEM based on GBInSAR

Science.gov (United States)

Yue, Jianping; Yue, Shun; Qiu, Zhiwei; Wang, Xueqin; Guo, Leping

2016-05-01

Precise topographical information has a very important role in geology, hydrology, natural resources survey and deformation monitoring. The extracting DEM technology based on synthetic aperture radar interferometry (InSAR) obtains the three-dimensional elevation of the target area through the phase information of the radar image data. The technology has large-scale, high-precision, all-weather features. By changing track in the location of the ground radar system up and down, it can form spatial baseline. Then we can achieve the DEM of the target area by acquiring image data from different angles. Three-dimensional laser scanning technology can quickly, efficiently and accurately obtain DEM of target area, which can verify the accuracy of DEM extracted by GBInSAR. But research on GBInSAR in extracting DEM of the target area is a little. For lack of theory and lower accuracy problems in extracting DEM based on GBInSAR now, this article conducted research and analysis on its principle deeply. The article extracted the DEM of the target area, combined with GBInSAR data. Then it compared the DEM obtained by GBInSAR with the DEM obtained by three-dimensional laser scan data and made statistical analysis and normal distribution test. The results showed the DEM obtained by GBInSAR was broadly consistent with the DEM obtained by three-dimensional laser scanning. And its accuracy is high. The difference of both DEM approximately obeys normal distribution. It indicated that extracting the DEM of target area based on GBInSAR is feasible and provided the foundation for the promotion and application of GBInSAR.

The effect of severe acute respiratory syndrome (SARS) on emergency airway management.

Science.gov (United States)

Wong, Evelyn; Ho, Khoy Kheng

2006-07-01

From early March 2003 to late May 2003, severe acute respiratory syndrome (SARS) was detected in Singapore. The increase in workload and new infection control procedures were thought to affect resuscitation and airway management. Our aim was to study the effects of wearing of personal protective equipment (PPE) and powered air-purifying respirator (PAPR) and the restriction in the number of resuscitation personnel on airway management during the SARS crisis. Data was collected prospectively through an ongoing emergency airway registry. The data was divided into three periods: (1) before PPE was instituted from 1 November 2002 to 31 March 2003; (2) during SARS (when PPE use was mandatory) from 1 April to 31 July 2003; (3) post-SARs (when PPE use was non-mandatory but encouraged) from 1 August to 31 March 2004. There was no change in patient demographics during the three periods. There were significant increases in the proportion of resuscitation cases and airway interventions during the SARS period compared to the pre-SARS period. The resident medical officer intubation rate decreased from 45.1% pre-SARS to 35.2% during SARS and 17.7% post-SARS. The complication rates were 10.5%, 9.9% and 9.4% in periods 1-3, respectively. Restriction in the number of healthcare staff attending to each patient may have influenced the department's decision to allow only the most confident or experienced personnel to manage the airway. The exposure of junior medical officers in emergency airway management during SARS and the immediate post-SARS period was decreased. This trend should be monitored further and intervention may be necessary should it continue to decline.

Nudging Students beyond the FAFSA: The Impact of University Outreach on Financial Aid Behaviors and Outcomes

Science.gov (United States)

Castleman, Benjamin L.; Meyer, Katharine E.; Sullivan, Zachary; Hartog, William D.; Miller, Scott

2017-01-01

A growing body of research indicates that proactive outreach from high schools and college access organizations about college preparation tasks, and specifically focusing on completing the Free Application for Federal Student Aid (FAFSA), results in increased college enrollment. Comparatively less attention has been paid to the role of colleges…

Synthetic aperture design for increased SAR image rate

Science.gov (United States)

Bielek, Timothy P [Albuquerque, NM; Thompson, Douglas G [Albuqerque, NM; Walker, Bruce C [Albuquerque, NM

2009-03-03

High resolution SAR images of a target scene at near video rates can be produced by using overlapped, but nevertheless, full-size synthetic apertures. The SAR images, which respectively correspond to the apertures, can be analyzed in sequence to permit detection of movement in the target scene.

The Danish polarimetric SAR for remote sensing applications

DEFF Research Database (Denmark)

Christensen, Erik Lintz; Madsen, Søren Nørvang; Dall, Jørgen

1994-01-01

Presents the Danish polarimetric SAR system, EMISAR, and the approach taken in the system design to achieve a reliable high performance system. The design and implementation of the antenna system as well as the analog and digital hardware are discussed. The SAR utilises a dual polarised microstri...

SEGMENTATION OF POLARIMETRIC SAR IMAGES USIG WAVELET TRANSFORMATION AND TEXTURE FEATURES

Directory of Open Access Journals (Sweden)

A. Rezaeian

2015-12-01

Full Text Available Polarimetric Synthetic Aperture Radar (PolSAR sensors can collect useful observations from earth’s surfaces and phenomena for various remote sensing applications, such as land cover mapping, change and target detection. These data can be acquired without the limitations of weather conditions, sun illumination and dust particles. As result, SAR images, and in particular Polarimetric SAR (PolSAR are powerful tools for various environmental applications. Unlike the optical images, SAR images suffer from the unavoidable speckle, which causes the segmentation of this data difficult. In this paper, we use the wavelet transformation for segmentation of PolSAR images. Our proposed method is based on the multi-resolution analysis of texture features is based on wavelet transformation. Here, we use the information of gray level value and the information of texture. First, we produce coherency or covariance matrices and then generate span image from them. In the next step of proposed method is texture feature extraction from sub-bands is generated from discrete wavelet transform (DWT. Finally, PolSAR image are segmented using clustering methods as fuzzy c-means (FCM and k-means clustering. We have applied the proposed methodology to full polarimetric SAR images acquired by the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR L-band system, during July, in 2012 over an agricultural area in Winnipeg, Canada.

Segmentation of Polarimetric SAR Images Usig Wavelet Transformation and Texture Features

Science.gov (United States)

Rezaeian, A.; Homayouni, S.; Safari, A.

2015-12-01

Polarimetric Synthetic Aperture Radar (PolSAR) sensors can collect useful observations from earth's surfaces and phenomena for various remote sensing applications, such as land cover mapping, change and target detection. These data can be acquired without the limitations of weather conditions, sun illumination and dust particles. As result, SAR images, and in particular Polarimetric SAR (PolSAR) are powerful tools for various environmental applications. Unlike the optical images, SAR images suffer from the unavoidable speckle, which causes the segmentation of this data difficult. In this paper, we use the wavelet transformation for segmentation of PolSAR images. Our proposed method is based on the multi-resolution analysis of texture features is based on wavelet transformation. Here, we use the information of gray level value and the information of texture. First, we produce coherency or covariance matrices and then generate span image from them. In the next step of proposed method is texture feature extraction from sub-bands is generated from discrete wavelet transform (DWT). Finally, PolSAR image are segmented using clustering methods as fuzzy c-means (FCM) and k-means clustering. We have applied the proposed methodology to full polarimetric SAR images acquired by the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) L-band system, during July, in 2012 over an agricultural area in Winnipeg, Canada.

Excretion and detection of SARS coronavirus and its nucleic acid from digestive system

Science.gov (United States)

Wang, Xin-Wei; Li, Jin-Song; Guo, Ting-Kai; Zhen, Bei; Kong, Qing-Xin; Yi, Bin; Li, Zhong; Song, Nong; Jin, Min; Wu, Xiao-Ming; Xiao, Wen-Jun; Zhu, Xiu-Mei; Gu, Chang-Qing; Yin, Jing; Wei, Wei; Yao, Wei; Liu, Chao; Li, Jian-Feng; Ou, Guo-Rong; Wang, Min-Nian; Fang, Tong-Yu; Wang, Gui-Jie; Qiu, Yao-Hui; Wu, Huai-Huan; Chao, Fu-Huan; Li, Jun-Wen

2005-01-01

AIM: To study whether severe acute respiratory syndrome coronavirus (SARS-CoV) could be excreted from digestive system. METHODS: Cell culture and semi-nested RT-PCR were used to detect SARS-CoV and its RNA from 21 stool and urine samples, and a kind of electropositive filter media particles was used to concentrate the virus in 10 sewage samples from two hospitals receiving SARS patients in Beijing in China. RESULTS: It was demonstrated that there was no live SARS-CoV in all samples collected, but the RNA of SARS-CoV could be detected in seven stool samples from SARS patients with any one of the symptoms of fever, malaise, cough, or dyspnea, in 10 sewage samples before disinfection and 3 samples after disinfection from the two hospitals. The RNA could not be detected in urine and stool samples from patients recovered from SARS. CONCLUSION: Nucleic acid of SARS-CoV can be excreted through the stool of patients into sewage system, and the possibility of SARS-CoV transmitting through digestive system cannot be excluded. PMID:16038039

Undergraduate teaching in geriatric medicine using computer-aided learning improves student performance in examinations.

Science.gov (United States)

Daunt, Laura A; Umeonusulu, Patience I; Gladman, John R F; Blundell, Adrian G; Conroy, Simon P; Gordon, Adam L

2013-07-01

computer-aided learning (CAL) is increasingly used to deliver teaching, but few studies have evaluated its impact on learning within geriatric medicine. We developed and implemented CAL packages on falls and continence, and evaluated their effect on student performance in two medical schools. traditional ward based and didactic teaching was replaced by blended learning (CAL package combined with traditional teaching methods). Examination scores were compared for cohorts of medical students receiving traditional learning and those receiving blended learning. Control questions were included to provide data on cohort differences. in both medical schools, there was a trend towards improved scores following blended learning, with a smaller number of students achieving low scores (P learning was associated with improvement in student examination performance, regardless of the setting or the methods adopted, and without increasing teaching time. Our findings support the use of CAL in teaching geriatric medicine, and this method has been adopted for teaching other topics in the undergraduate curriculum.

PSInSAR technology and its use for monitoring of the Earth's surface deformation; Technologia PSInSAR a jej vyuzitie na monitorovanie deformacii zemskeho povrchu

Energy Technology Data Exchange (ETDEWEB)

Batorova, K [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra inzinierskej geologie, 84215 Bratislava (Slovakia)

2012-04-25

Method of permanent reflex points (PSInSAR) allows to monitor the time evolution of deformations of the Earth's surface with a millimeter precision. For deformation size determination there are used the maps of movement speed or time delay of line set of data that are obtained by evaluating of SAR images. SAR files must be processed using the basic mathematical calculation presented in the work, with an emphasis on the parameters used in geology. Extensive processing of multiple SAR imagery showed that they can be used during monitoring of the field with an accurate identification of the objects on the Earth's surface, which provide a stable reflection of radar rays transmitted from the satellite. These objects are known as permanent reflection points (PS). PS can be geo-referenced, allowing accurate determination of the movement size of the Earth's surface deformation. In this paper an example of using of PSInSAR technology for monitoring of slope movements on the territory of Slovakia is presented. (authors)

Analysis of Spatiotemporal Characteristics of Pandemic SARS Spread in Mainland China

Directory of Open Access Journals (Sweden)

Chunxiang Cao

2016-01-01

Full Text Available Severe acute respiratory syndrome (SARS is one of the most severe emerging infectious diseases of the 21st century so far. SARS caused a pandemic that spread throughout mainland China for 7 months, infecting 5318 persons in 194 administrative regions. Using detailed mainland China epidemiological data, we study spatiotemporal aspects of this person-to-person contagious disease and simulate its spatiotemporal transmission dynamics via the Bayesian Maximum Entropy (BME method. The BME reveals that SARS outbreaks show autocorrelation within certain spatial and temporal distances. We use BME to fit a theoretical covariance model that has a sine hole spatial component and exponential temporal component and obtain the weights of geographical and temporal autocorrelation factors. Using the covariance model, SARS dynamics were estimated and simulated under the most probable conditions. Our study suggests that SARS transmission varies in its epidemiological characteristics and SARS outbreak distributions exhibit palpable clusters on both spatial and temporal scales. In addition, the BME modelling demonstrates that SARS transmission features are affected by spatial heterogeneity, so we analyze potential causes. This may benefit epidemiological control of pandemic infectious diseases.

Chinese HJ-1C SAR And Its Wind Mapping Capability

Science.gov (United States)

Huang, Weigen; Chen, Fengfeng; Yang, Jingsong; Fu, Bin; Chen, Peng; Zhang, Chan

2010-04-01

Chinese Huan Jing (HJ)-1C synthetic aperture radar (SAR) satellite has been planed to be launched in 2010. HJ-1C satellite will fly in a sun-synchronous polar orbit of 500-km altitude. SAR will be the only sensor on board the satellite. It operates in S band with VV polarization. Its image mode has the incidence angles 25°and 47°at the near and far sides of the swath respectively. There are two selectable SAR modes of operation, which are fine resolution beams and standard beams respectively. The sea surface wind mapping capability of the SAR has been examined using M4S radar imaging model developed by Romeiser. The model is based on Bragg scattering theory in a composite surface model expansion. It accounts for contributions of the full ocean wave spectrum to the radar backscatter from ocean surface. The model reproduces absolute normalized radar cross section (NRCS) values for wide ranges of wind speeds. The model results of HJ-1C SAR have been compared with the model results of Envisat ASAR. It shows that HJ-1C SAR is as good as Envisat ASAR at sea surface wind mapping.

HIV/AIDS Knowledge, Perception of Knowledge and Sources of Information among University Students in USA, Turkey, South Africa and Nigeria

Science.gov (United States)

Abiona, Titilayo; Balogun, Joseph; Yohannes, Eden; Adefuye, Adedeji; Yakut, Yavuz; Amosun, Seyi; Frantz, Jose

2014-01-01

Objective: To examine HIV/AIDS knowledge, perceptions of knowledge and sources of HIV information among university students in four countries with different HIV prevalence rates. Methods: A survey was completed by 2,570 randomly selected university students from the USA, Turkey, South Africa and Nigeria. Logistic regression analysis was used to…

ANALYSIS OF MULTIPATH PIXELS IN SAR IMAGES

Directory of Open Access Journals (Sweden)

J. W. Zhao

2016-06-01

Full Text Available As the received radar signal is the sum of signal contributions overlaid in one single pixel regardless of the travel path, the multipath effect should be seriously tackled as the multiple bounce returns are added to direct scatter echoes which leads to ghost scatters. Most of the existing solution towards the multipath is to recover the signal propagation path. To facilitate the signal propagation simulation process, plenty of aspects such as sensor parameters, the geometry of the objects (shape, location, orientation, mutual position between adjacent buildings and the physical parameters of the surface (roughness, correlation length, permittivitywhich determine the strength of radar signal backscattered to the SAR sensor should be given in previous. However, it's not practical to obtain the highly detailed object model in unfamiliar area by field survey as it's a laborious work and time-consuming. In this paper, SAR imaging simulation based on RaySAR is conducted at first aiming at basic understanding of multipath effects and for further comparison. Besides of the pre-imaging simulation, the product of the after-imaging, which refers to radar images is also taken into consideration. Both Cosmo-SkyMed ascending and descending SAR images of Lupu Bridge in Shanghai are used for the experiment. As a result, the reflectivity map and signal distribution map of different bounce level are simulated and validated by 3D real model. The statistic indexes such as the phase stability, mean amplitude, amplitude dispersion, coherence and mean-sigma ratio in case of layover are analyzed with combination of the RaySAR output.

Early appearance of SARS on chest CT scan

International Nuclear Information System (INIS)

Cheng Xiaoguang; Feng Suchen; Xia Guoguang; Zhao Tao; Gu Xiang; Qu Hui

2003-01-01

Objective: To evaluate the early appearance of SARS on chest CT scan and its role in the early diagnosis. Methods: Forty cases of SARS in keeping with the criteria of the Ministry of Health had chest CT scans within 7 days of onset of symptoms, and CR chest X-ray films were available as well. These chest X-rays and CT images were retrospectively reviewed to determine if there were any abnormalities on the images. The lesions on the chest CT images were then further analyzed in terms of the number, location, size, and density. Results: Positive abnormalities on chest CT scans were revealed in all 40 SARS cases. Positive findings on CR chest films were showed in only 25 cases, equivocal in 6, and normal in 9 cases. The main abnormalities seen on CT and X-rays were pulmonary infiltrations varied markedly in severity. 70 % cases had 1 or 2 lesions on chest CT scan, 30 % cases had 3 or more lesions. The lesions seen on chest CT scan tended to be ground-glass opacification, sometimes with consolidation which was very faint and inhomogeneous, easily missed on chest X-rays. Typically the lesions were located in the periphery of the lung, or both central and peripheral lung, but very rare in a pure central location. They were commonly in the shape of patch or ball. Conclusions: Chest CT scan is much more sensitive in detecting the lesions of the lung in SARS. The early appearance of SARS on chest CT scan is characteristic but non-specific, indicating that chest CT scan plays a very important role in the early diagnosis and differential diagnosis of SARS

Slope Superficial Displacement Monitoring by Small Baseline SAR Interferometry Using Data from L-band ALOS PALSAR and X-band TerraSAR: A Case Study of Hong Kong, China

Directory of Open Access Journals (Sweden)

Fulong Chen

2014-02-01

Full Text Available Owing to the development of spaceborne synthetic aperture radar (SAR platforms, and in particular the increase in the availability of multi-source (multi-band and multi-resolution data, it is now feasible to design a surface displacement monitoring application using multi-temporal SAR interferometry (MT-InSAR. Landslides have high socio-economic impacts in many countries because of potential geo-hazards and heavy casualties. In this study, taking into account the merits of ALOS PALSAR (L-band, good coherence preservation and TerraSAR (X-band, high resolution and short revisit times data, we applied an improved small baseline InSAR (SB-InSAR with 3-D phase unwrapping approach, to monitor slope superficial displacement in Hong Kong, China, a mountainous subtropical zone city influenced by over-urbanization and heavy monsoonal rains. Results revealed that the synergistic use of PALSAR and TerraSAR data produces different outcomes in relation to data reliability and spatial-temporal resolution, and hence could be of significant value for a comprehensive understanding and monitoring of unstable slopes.

Segment-based change detection for polarimetric SAR data

DEFF Research Database (Denmark)

Skriver, Henning; Nielsen, Allan Aasbjerg; Conradsen, Knut

2006-01-01

that is needed compared to single polarisation SAR to provide reliable and robust detection of changes. Polarimetric SAR data will be available from satellites in the near future, e.g. the Japanese ALOS, the Canadian Radarsat-2 and the German TerraSAR-X. An appropriate way of representing multi-look fully...... be split into a number of smaller fields, a building may be removed from or added to some area, hedgerows may be removed/added or other type of vegetated areas may be partly removed or added. In this case, ambiguities may arise when segments have changed shape and extent from one image to another...

Evaluation of a School-Based Train-the-Trainer Intervention Program to Teach First Aid and Risk Reduction among High School Students

Science.gov (United States)

Carruth, Ann K.; Pryor, Susan; Cormier, Cathy; Bateman, Aaron; Matzke, Brenda; Gilmore, Karen

2010-01-01

Background: Farming is a hazardous occupation posing health risks from agricultural exposures for the farm owner and family members. First Aid for Rural Medical Emergencies (F.A.R.M.E.) was developed to support a train-the-trainer (TTT) program to prepare high school students to teach first aid skills and risk reduction through peer interaction.…

Crop Classification Using Short-Revisit Multitemporal SAR Data

DEFF Research Database (Denmark)

Skriver, Henning; Mattia, Francesco; Satalino, Giuseppe

2011-01-01

Classification of crops and other land cover types is an important application of both optical/infrared and SAR satellite data. It is already an import application of present satellite systems, as it will be for planned missions, such as the Sentinels. An airborne SAR data set with a short revisi...

Localized landslide risk assessment with multi pass L band DInSAR analysis

Science.gov (United States)

Yun, HyeWon; Rack Kim, Jung; Lin, Shih-Yuan; Choi, YunSoo

2014-05-01

In terms of data availability and error correction, landslide forecasting by Differential Interferometric SAR (DInSAR) analysis is not easy task. Especially, the landslides by the anthropogenic construction activities frequently occurred in the localized cutting side of mountainous area. In such circumstances, it is difficult to attain sufficient enough accuracy because of the external factors inducing the error component in electromagnetic wave propagation. For instance, the local climate characteristics such as orographic effect and the proximity to water source can produce the significant anomalies in the water vapor distribution and consequently result in the error components of InSAR phase angle measurements. Moreover the high altitude parts of target area cause the stratified tropospheric delay error in DInSAR measurement. The other obstacle in DInSAR observation over the potential landside site is the vegetation canopy which causes the decorrelation of InSAR phase. Thus rather than C band sensor such as ENVISAT, ERS and RADARSAT, DInSAR analysis with L band ALOS PLASAR is more recommendable. Together with the introduction of L band DInSAR analysis, the improved DInSAR technique to cope all above obstacles is necessary. Thus we employed two approaches i.e. StaMPS/MTI (Stanford Method for Persistent Scatterers/Multi-Temporal InSAR, Hopper et al., 2007) which was newly developed for extracting the reliable deformation values through time series analysis and two pass DInSAR with the error term compensation based on the external weather information in this study. Since the water vapor observation from spaceborne radiometer is not feasible by the temporal gap in this case, the quantities from weather Research Forecasting (WRF) with 1 km spatial resolution was used to address the atmospheric phase error in two pass DInSAR analysis. Also it was observed that base DEM offset with time dependent perpendicular baselines of InSAR time series produce a significant error

Science data collection with polarimetric SAR

DEFF Research Database (Denmark)

Dall, Jørgen; Woelders, Kim; Madsen, Søren Nørvang

1996-01-01

Discusses examples on the use of polarimetric SAR in a number of Earth science studies. The studies are presently being conducted by the Danish Center for Remote Sensing. A few studies of the European Space Agency's EMAC programme are also discussed. The Earth science objectives are presented......, and the potential of polarimetric SAR is discussed and illustrated with data collected by the Danish airborne EMISAR system during a number of experiments in 1994 and 1995. The presentation will include samples of data acquired for the different studies...

Potential of TCPInSAR in Monitoring Linear Infrastructure with a Small Dataset of SAR Images: Application of the Donghai Bridge, China

Directory of Open Access Journals (Sweden)

Lei Zhang

2018-03-01

Full Text Available Reliably monitoring deformation associated with linear infrastructures, such as long-span bridges, is vitally important to assess their structural health. In this paper, we attempt to employ satellite interferometric synthetic aperture radar (InSAR to map the deformation of Donghai Bridge over a half of an annual cycle. The bridge, as the fourth longest cross-sea bridge in the world, located in the north of Hangzhou Bay, East China Sea where the featureless sea surface largely occupied the radar image raises challenges to accurately co-register the coherent points along the bridge. To tackle the issues due to co-registration and the limited number of synthetic aperture radar (SAR images, we adopt the termed temporarily-coherent point (TCP InSAR (TCPInSAR technique to process the radar images. TCPs that are not necessarily coherent during the whole observation period can be identified within every two SAR acquisitions during the co-registration procedure based on the statistics of azimuth and range offsets. In the process, co-registration is performed only using the offsets of these TCPs, leading to improved interferometric phases and the local Delaunay triangulation is used to construct point pairs to reduce the atmospheric artifacts along the bridge. With the TCPInSAR method the deformation rate along the bridge is estimated with no need of phase unwrapping. The achieved result reveals that the Donghai Bridge suffered a line-of-sight (LOS deformation rate up to −2.3 cm/year from January 2009 to July 2009 at the cable-stayed part, which is likely due to the thermal expansion of cables.

Knowledge of HIV/AIDS, attitudes towards sexual risk behaviour and perceived behavioural control among college students in Botswana

Directory of Open Access Journals (Sweden)

Gabriel Faimau

2016-12-01

Full Text Available This study examines the knowledge of HIV/AIDS, attitudes towards risky sexual behaviour and perceived behavioural control among students in Botswana. Data were collected from 445 students randomly selected from the University of Botswana and Boitekanelo College. Hundred and seventy three males and 272 females participated in the study. The study established that although more than 90% of students correctly identified routes of HIV transmission, misconceptions regarding HIV/AIDS still exist. This includes the belief that people can be infected with HIV because of witchcraft and that only people who have sex with gay or homosexual partners can be infected with HIV. Majority of students were aware of various sexual risks. However, the percentage of students who indicated that “it is difficult to ask my partner to use a condom” was still relatively high (13.5% based on the assumption that students are supposed to know the consequences of sexual risky behaviour. It was also found that male students were 3.48 times more likely to negotiate sex than their female counterparts (OR = 3.48, 95% CI: 1.09 − 11.13 and students who were 18 years and below were more likely to negotiate sex than students above 18 years of age (OR = 2.78, 95% CI: 1.42 − 18.32. Christians are four times less likely to negotiate sex compared to non-Christians (OR = 0.219, 95% CI: 0.095 − 0.506. More than 80% of students were comfortable discussing HIV or sex and sexuality with their friends, boyfriends/girlfriends or partners but uncomfortable discussing the same issues with their parents.

Life skills as a behaviour change strategy in the prevention of HIV and AIDS: Perceptions of students in an open and distance learning institution.

Science.gov (United States)

Mohapi, B J; Pitsoane, E M

2017-12-01

The prevention of HIV and AIDS, especially amongst young people, is very important, as they are the future leaders. South Africa carries a high burden of the HIV and AIDS disease, and efforts at the prevention of the disease need to be intensified. University students are also at risk, and prevention efforts need to be intensified to ensure that students graduate and enter the world of work to become productive citizens. Failure to pay attention to preventative behaviour amongst university students may have negative socio-economic consequences for the country. The paper presents a quantitative study undertaken amongst students at the University of South Africa, an Open and Distance Learning Institution in South Africa. The aim of the study was to explore the perceptions of students regarding life skills as a behaviour change strategy at Unisa. The study was conducted in the three regions of the University: Midlands region, Gautengregion and Limpopo region. Data were collected by means of self-administered questionnaires and were analysed by using the Statistical Programme for Social Sciences. The findings revealed that students have a need to attend life skills workshops, which are facilitated by trained student counsellors since they believe that the life skills training will assist them to be assertive and practise behaviours which will not make them vulnerable to the HIV and AIDS infection.

Detecting and monitoring UCG subsidence with InSAR

Energy Technology Data Exchange (ETDEWEB)

Mellors, R J; Foxall, W; Yang, X

2012-03-23

The use of interferometric synthetic aperture radar (InSAR) to measure surface subsidence caused by Underground Coal Gasification (UCG) is tested. InSAR is a remote sensing technique that uses Synthetic Aperture Radar images to make spatial images of surface deformation and may be deployed from satellite or an airplane. With current commercial satellite data, the technique works best in areas with little vegetation or farming activity. UCG subsidence is generally caused by roof collapse, which adversely affects UCG operations due to gas loss and is therefore important to monitor. Previous studies have demonstrated the usefulness of InSAR in measuring surface subsidence related to coal mining and surface deformation caused by a coal mining roof collapse in Crandall Canyon, Utah is imaged as a proof-of-concept. InSAR data is collected and processed over three known UCG operations including two pilot plants (Majuba, South Africa and Wulanchabu, China) and an operational plant (Angren, Uzbekistan). A clear f eature showing approximately 7 cm of subsidence is observed in the UCG field in Angren. Subsidence is not observed in the other two areas, which produce from deeper coal seams and processed a smaller volume. The results show that in some cases, InSAR is a useful tool to image UCG related subsidence. Data from newer satellites and improved algorithms will improve effectiveness.

MAPPING THE EXTENT AND MAGNITUDE OF SEVER FLOODING INDUCED BY HURRICANE IRMA WITH MULTI-TEMPORAL SENTINEL-1 SAR AND INSAR OBSERVATIONS

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B. Zhang

2018-04-01

Full Text Available During Hurricane Irma’s passage over Florida in September 2017, many sections of the state experienced heavy rain and sequent flooding. In order to drain water out of potential flooding zones and assess property damage, it is important to map the extent and magnitude of the flooded areas at various stages of the storm. We use Synthetic Aperture Radar (SAR and Interferometric SAR (InSAR observations, acquired by Sentinel-1 before, during and after the hurricane passage, which enable us to evaluate surface condition during different stages of the hurricane. This study uses multi-temporal images acquired under dry condition before the hurricane to constrain the background backscattering signature. Flooded areas are detected when the backscattering during the hurricane is statistically significantly different from the average dry conditions. The detected changes can be either an increase or decrease of the backscattering, which depends on the scattering characteristics of the surface. In addition, water level change information in Palmdale, South Florida is extracted from an interferogram with the aid of a local water gauge as the reference. The results of our flooding analysis revealed that the majority of the study area in South Florida was flooded during Hurricane Irma.

Common SAR Derived from Linear and Non-linear QSAR Studies on AChE Inhibitors used in the Treatment of Alzheimer's Disease.

Science.gov (United States)

Pulikkal, Babitha Pallikkara; Marunnan, Sahila Mohammed; Bandaru, Srinivas; Yadav, Mukesh; Nayarisseri, Anuraj; Sureshkumar, Sivanpillai

2017-11-14

Deficits in cholinergic neurotransmission due to the degeneration of cholinergic neurons in the brain are believed to be one of the major causes of the memory impairments associated with AD. Targeting acetyl cholinesterase (AChE) surfaced as a potential therapeutic target in the treatment of Alzheimer's disease. The present study is pursued to develop quantitative structure activity relationship (QSAR) models to determine chemical descriptors responsible for AChE activity. Two different sets of AChE inhibitors, dataset-I (30 compounds) and dataset-II (20 compounds) were investigated through MLR aided linear and SVM aided non-linear QSAR models. The obtained QSAR models were found statistically fit, stable and predictive on validation scales. These QSAR models were further investigated for their common structure-activity relationship in terms of overlapping molecular descriptors selection. Atomic mass weighted 3D Morse descriptors (MATS5m) and Radial Distribution Function (RDF045m) descriptors were found in common SAR for both the datasets. Electronegativity weighted (MATS5e, HATSe, and Mor17e) descriptors have also been identified in regulative roles towards endpoint values of dataset-I and dataset-II. The common SAR identified in these linear and non-linear QSAR models could be utilized to design novel inhibitors of AChE with improved biological activity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Assessment of knowledge, attitude and risk behaviors towards HIV/AIDS and other sexual transmitted infection among preparatory students of Gondar town, north west Ethiopia

Directory of Open Access Journals (Sweden)

Shiferaw Yitayal

2011-11-01

Full Text Available Abstract Background The first case of HIV in Ethiopia was reported in 1984. Since then, HIV/AIDS has become a major public health concern in the country, leading the Government of Ethiopia to declare a public health emergency in 2002. Although the epidemic is currently stable, HIV/AIDS remains a major development challenge for Ethiopia. The spread of HIV in any community is in part determined by the knowledge of attitude towards sexuality of its members and by their actual sexual practices. The aim of the study was to assess students' knowledge, attitudes and practices regarding HIV/AIDS and STDs in Gondar, North West Ethiopia. Methods A cross sectional study was conducted between February 1 to March 1, 2009 in preparatory high school students. Pre-tested questioner was used to generate the data and analysis was made by SPSS version 15. Chi -square value was calculated and p-value Results All the students had heard about AIDS before the interview. Knowledge on some aspect of the disease was quite low in the study group. Only half of the students knew that at present, AIDs is incurable and that HIV infection can be acquired through sexual contact with a 'familiar' person. Knowledge about STI was also quite low, 39% knew that pus in the urine is a symptom of STI and 45.4% knew that acquisition of other STIs is increases the chance of HIV transmission following unsafe sex with known cases. 25% of the study group had previous sexual intercourse and exposed at least one risk behavior. About 34% of the respondents had negative attitude towards AIDS and STDs. Conclusion Awareness about STDs and methods of prevention of HIV and STDs was low. More risk behavior was observed in male and those with alcohol and drugs of abuse.

Performance Analysis for Airborne Interferometric SAR Affected by Flexible Baseline Oscillation

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Liu Zhong-sheng

2014-04-01

Full Text Available The airborne interferometric SAR platform suffers from instability factors, such as air turbulence and mechanical vibrations during flight. Such factors cause the oscillation of the flexible baseline, which leads to significant degradation of the performance of the interferometric SAR system. This study is concerned with the baseline oscillation. First, the error of the slant range model under baseline oscillation conditions is formulated. Then, the SAR complex image signal and dual-channel correlation coefficient are modeled based on the first-order, second-order, and generic slant range error. Subsequently, the impact of the baseline oscillation on the imaging and interferometric performance of the SAR system is analyzed. Finally, simulations of the echo data are used to validate the theoretical analysis of the baseline oscillation in the airborne interferometric SAR.

Space Radar Image of West Texas - SAR scan

Science.gov (United States)

1999-01-01

This radar image of the Midland/Odessa region of West Texas, demonstrates an experimental technique, called ScanSAR, that allows scientists to rapidly image large areas of the Earth's surface. The large image covers an area 245 kilometers by 225 kilometers (152 miles by 139 miles). It was obtained by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) flying aboard the space shuttle Endeavour on October 5, 1994. The smaller inset image is a standard SIR-C image showing a portion of the same area, 100 kilometers by 57 kilometers (62 miles by 35 miles) and was taken during the first flight of SIR-C on April 14, 1994. The bright spots on the right side of the image are the cities of Odessa (left) and Midland (right), Texas. The Pecos River runs from the top center to the bottom center of the image. Along the left side of the image are, from top to bottom, parts of the Guadalupe, Davis and Santiago Mountains. North is toward the upper right. Unlike conventional radar imaging, in which a radar continuously illuminates a single ground swath as the space shuttle passes over the terrain, a Scansar radar illuminates several adjacent ground swaths almost simultaneously, by 'scanning' the radar beam across a large area in a rapid sequence. The adjacent swaths, typically about 50 km (31 miles) wide, are then merged during ground processing to produce a single large scene. Illumination for this L-band scene is from the top of the image. The beams were scanned from the top of the scene to the bottom, as the shuttle flew from left to right. This scene was acquired in about 30 seconds. A normal SIR-C image is acquired in about 13 seconds. The ScanSAR mode will likely be used on future radar sensors to construct regional and possibly global radar images and topographic maps. The ScanSAR processor is being designed for 1996 implementation at NASA's Alaska SAR Facility, located at the University of Alaska Fairbanks, and will produce digital images from the

Genomic Characterization of Two Novel SAR11 Isolates From the Red Sea, Including the First Strain of the SAR11 Ib clade

KAUST Repository

Jimenez Infante, Francy M.

2017-06-22

The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea, one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain-specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter.

Genomic Characterization of Two Novel SAR11 Isolates From the Red Sea, Including the First Strain of the SAR11 Ib clade

KAUST Repository

Jimenez Infante, Francy M.; Ngugi, David; Vinu, Manikandan; Blom, Jochen; Alam, Intikhab; Bajic, Vladimir B.; Stingl, Ulrich

2017-01-01

The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea, one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain-specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter.

SAR compliance assessment of PMR 446 and FRS walkie-talkies.

Science.gov (United States)

Vermeeren, Günter; Joseph, Wout; Martens, Luc

2015-10-01

The vast amount of studies on radiofrequency dosimetry deal with exposure due to mobile devices and base station antennas for cellular communication systems. This study investigates compliance of walkie-talkies to exposure guidelines established by the International Commission on Non-Ionizing Radiation Protection and the Federal Communications Committee. The generic walkie-talkie consisted of a helical antenna and a ground plane and was derived by reverse engineering of a commercial walkie-talkie. Measured and simulated values of antenna characteristics and electromagnetic near fields of the generic walkie-talkie were within 2% and 8%, respectively. We also validated normalized electromagnetic near fields of the generic walkie-talkie against a commercial device and observed a very good agreement (deviation based on magnetic near field. Finally, we found that SAR of commercial devices is within current SAR limits for general public exposure for a worst-case duty cycle of 100%, that is, about 3 times and 6 times lower than the limit on the 1 g SAR (1.6 W/kg) and 10 g SAR (2 W/kg), respectively. But, an effective radiated power as specified by the Private Mobile Radio at 446 MHz (PMR 446) radio standard can cause localized SAR exceeding SAR limits for 1 g of tissue. © 2015 Wiley Periodicals, Inc.

Estimating soil moisture using the Danish polarimetric SAR

DEFF Research Database (Denmark)

Jiankang, Ji; Thomsen, A.; Skriver, Henning

1995-01-01

The results of applying data from the Danish polarimetric SAR (EMISAR) to estimate soil moisture for bare fields are presented. Fully calibrated C-band SAR images for hh, vv and cross polarizations have been used in this study. The measured surface roughness data showed that classical roughness a...... of surface parameters with the bilinear model, the correlation coefficient between the estimated and measured soil moisture, as well as rms height, is about 0.77. To improve the result, the local incidence angles need to be taken into account......The results of applying data from the Danish polarimetric SAR (EMISAR) to estimate soil moisture for bare fields are presented. Fully calibrated C-band SAR images for hh, vv and cross polarizations have been used in this study. The measured surface roughness data showed that classical roughness...... autocorrelation functions (Gaussian and Exponential) were not able to fit natural surfaces well. A Gauss-Exp hybrid model which agreed better with the measured data has been proposed. Theoretical surface scattering models (POM, IEM), as well as an empirical model for retrieval of soil moisture and surface rms...

First Aid Challenge

Science.gov (United States)

Roman, Harry T.

2011-01-01

This article describes a challenge wherein students will be asked to design a portable first aid kit that is normally carried in a recreational vehicle (RV), but can also be hand-carried or backpacked off road for distances of approximately 1-2 miles. This can be a very practical challenge for the students because it touches everyone. Everybody…

2011-12 National Postsecondary Student Aid Study (NPSAS:12). Price Estimates for Attending Postsecondary Education Institutions. First Look. NCES 2014-166

Science.gov (United States)

Simone, Sean; Radwin, David; Wine, Jennifer; Siegel, Peter; Bryan, Michael

2013-01-01

This First Look publication provides price estimates for attending postsecondary education institutions using data from the 2011-12 National Postsecondary Student Aid Study (NPSAS:12), the most comprehensive, nationally representative survey of student financing of postsecondary education in the United States. The survey includes about 95,000…

SAR11 bacteria linked to ocean anoxia and nitrogen loss

DEFF Research Database (Denmark)

Tsementzi, Despina; Wu, Jieying; Deutsch, Samuel

2016-01-01

Bacteria of the SAR11 clade constitute up to one half of all microbial cells in the oxygen-rich surface ocean. SAR11 bacteria are also abundant in oxygen minimum zones (OMZs), where oxygen falls below detection and anaerobic microbes have vital roles in converting bioavailable nitrogen to N2 gas...... activity. These results link SAR11 to pathways of ocean nitrogen loss, redefining the ecological niche of Earth’s most abundant organismal group....

A practical tablet-based hearing aid configuration as an exemplar project for students of instrumentation

Directory of Open Access Journals (Sweden)

Ricardo Simeoni

2015-06-01

Full Text Available This paper presents the configuration and digital signal processing details of a tablet-based hearing aid transmitting wirelessly to standard earphones, whereby the tablet performs full sound processing rather than solely providing a means of setting adjustment by streaming to conventional digital hearing aids. The presented device confirms the recognized advantages of this tablet-based approach (e.g., in relation to cost, frequency domain processing, amplification range, versatility of functionality, component battery rechargeability, and flags the future wider-spread availability of such hearing solutions within mainstream healthcare. The use of a relatively high sampling frequency was found to be beneficial for device performance, while the use of optional off-the-shelf add-on components (e.g., data acquisition device, high fidelity microphone, compact wireless transmitter/ receiver, wired headphones are also discussed in relation to performance optimization. The easy-to-follow configuration utilized is well suited to student learning/research instrumentation projects within the health and biomedical sciences. In this latter regard, the presented device was pedagogically integrated into a flipped classroom approach for the teaching of bioinstrumentation within an Allied Health Sciences School, with the subsequent establishment of positive student engagement outcomes.

A Practical Tablet-Based Hearing Aid Configuration as an Exemplar Project for Students of Instrumentation.

Science.gov (United States)

Simeoni, Ricardo

2015-06-11

This paper presents the configuration and digital signal processing details of a tablet-based hearing aid transmitting wirelessly to standard earphones, whereby the tablet performs full sound processing rather than solely providing a means of setting adjustment by streaming to conventional digital hearing aids. The presented device confirms the recognized advantages of this tablet-based approach (e.g., in relation to cost, frequency domain processing, amplification range, versatility of functionality, component battery rechargeability), and flags the future wider-spread availability of such hearing solutions within mainstream healthcare. The use of a relatively high sampling frequency was found to be beneficial for device performance, while the use of optional off-the-shelf add-on components (e.g., data acquisition device, high fidelity microphone, compact wireless transmitter/receiver, wired headphones) are also discussed in relation to performance optimization. The easy-to-follow configuration utilized is well suited to student learning/research instrumentation projects within the health and biomedical sciences. In this latter regard, the presented device was pedagogically integrated into a flipped classroom approach for the teaching of bioinstrumentation within an Allied Health Sciences School, with the subsequent establishment of positive student engagement outcomes.

On Signal Modeling of Moon-Based Synthetic Aperture Radar (SAR Imaging of Earth

Directory of Open Access Journals (Sweden)

Zhen Xu

2018-03-01

Full Text Available The Moon-based Synthetic Aperture Radar (Moon-Based SAR, using the Moon as a platform, has a great potential to offer global-scale coverage of the earth’s surface with a high revisit cycle and is able to meet the scientific requirements for climate change study. However, operating in the lunar orbit, Moon-Based SAR imaging is confined within a complex geometry of the Moon-Based SAR, Moon, and Earth, where both rotation and revolution have effects. The extremely long exposure time of Moon-Based SAR presents a curved moving trajectory and the protracted time-delay in propagation makes the “stop-and-go” assumption no longer valid. Consequently, the conventional SAR imaging technique is no longer valid for Moon-Based SAR. This paper develops a Moon-Based SAR theory in which a signal model is derived. The Doppler parameters in the context of lunar revolution with the removal of ‘stop-and-go’ assumption are first estimated, and then characteristics of Moon-Based SAR imaging’s azimuthal resolution are analyzed. In addition, a signal model of Moon-Based SAR and its two-dimensional (2-D spectrum are further derived. Numerical simulation using point targets validates the signal model and enables Doppler parameter estimation for image focusing.

SAR Ambiguity Study for the Cassini Radar

Science.gov (United States)

Hensley, Scott; Im, Eastwood; Johnson, William T. K.

1993-01-01

The Cassini Radar's synthetic aperture radar (SAR) ambiguity analysis is unique with respect to other spaceborne SAR ambiguity analyses owing to the non-orbiting spacecraft trajectory, asymmetric antenna pattern, and burst mode of data collection. By properly varying the pointing, burst mode timing, and radar parameters along the trajectory this study shows that the signal-to-ambiguity ratio of better than 15 dB can be achieved for all images obtained by the Cassini Radar.

Pulse-based internal calibration of polarimetric SAR

DEFF Research Database (Denmark)

Dall, Jørgen; Skou, Niels; Christensen, Erik Lintz

1994-01-01

Internal calibration greatly diminishes the dependence on calibration target deployment compared to external calibration. Therefore the Electromagnetics Institute (EMI) at the Technical University of Denmark (TUD) has equipped its polarimetric SAR, EMISAR, with several calibration loops and devel......Internal calibration greatly diminishes the dependence on calibration target deployment compared to external calibration. Therefore the Electromagnetics Institute (EMI) at the Technical University of Denmark (TUD) has equipped its polarimetric SAR, EMISAR, with several calibration loops...

Multi-look polarimetric SAR image filtering using simulated annealing

DEFF Research Database (Denmark)

Schou, Jesper

2000-01-01

Based on a previously published algorithm capable of estimating the radar cross-section in synthetic aperture radar (SAR) intensity images, a new filter is presented utilizing multi-look polarimetric SAR images. The underlying mean covariance matrix is estimated from the observed sample covariance...

The integration of Human Factors (HF) in the SAR process training course text

International Nuclear Information System (INIS)

Ryan, T.G.

1995-03-01

This text provides the technical basis for a two-day course on human factors (HF), as applied to the Safety Analysis Report (SAR) process. The overall objective of this text and course is to: provide the participant with a working knowledge of human factors-related requirements, suggestions for doing a human safety analysis applying a graded approach, and an ability to demonstrate using the results of the human safety analysis, that human factors elements as defined by DOE (human factors engineering, procedures, training, oversight, staffing, qualifications), can support wherever necessary, nuclear safety commitments in the SAR. More specifically, the objectives of the text and course are: (1) To provide the SAR preparer with general guidelines for doing HE within the context of a graded approach for the SAR; (2) To sensitize DOE facility managers and staff, safety analysts and SAR preparers, independent reviewers, and DOE reviewers and regulators, to DOE Order 5480.23 requirements for HE in the SAR; (3) To provide managers, analysts, reviewers and regulators with a working knowledge of HE concepts and techniques within the context of a graded approach for the SAR, and (4) To provide SAR managers and DOE reviewers and regulators with general guidelines for monitoring and coordinating the work of preparers of HE inputs throughout the SAR process, and for making decisions regarding the safety relevance of HE inputs to the SAR. As a ready reference for implementing the human factors requirements of DOE Order 5480.22 and DOE Standard 3009-94, this course text and accompanying two-day course are intended for all persons who are involved in the SAR

The integration of Human Factors (HF) in the SAR process training course text

Energy Technology Data Exchange (ETDEWEB)

Ryan, T.G.

1995-03-01

This text provides the technical basis for a two-day course on human factors (HF), as applied to the Safety Analysis Report (SAR) process. The overall objective of this text and course is to: provide the participant with a working knowledge of human factors-related requirements, suggestions for doing a human safety analysis applying a graded approach, and an ability to demonstrate using the results of the human safety analysis, that human factors elements as defined by DOE (human factors engineering, procedures, training, oversight, staffing, qualifications), can support wherever necessary, nuclear safety commitments in the SAR. More specifically, the objectives of the text and course are: (1) To provide the SAR preparer with general guidelines for doing HE within the context of a graded approach for the SAR; (2) To sensitize DOE facility managers and staff, safety analysts and SAR preparers, independent reviewers, and DOE reviewers and regulators, to DOE Order 5480.23 requirements for HE in the SAR; (3) To provide managers, analysts, reviewers and regulators with a working knowledge of HE concepts and techniques within the context of a graded approach for the SAR, and (4) To provide SAR managers and DOE reviewers and regulators with general guidelines for monitoring and coordinating the work of preparers of HE inputs throughout the SAR process, and for making decisions regarding the safety relevance of HE inputs to the SAR. As a ready reference for implementing the human factors requirements of DOE Order 5480.22 and DOE Standard 3009-94, this course text and accompanying two-day course are intended for all persons who are involved in the SAR.

Fusion method of SAR and optical images for urban object extraction

Science.gov (United States)

Jia, Yonghong; Blum, Rick S.; Li, Fangfang

2007-11-01

A new image fusion method of SAR, Panchromatic (Pan) and multispectral (MS) data is proposed. First of all, SAR texture is extracted by ratioing the despeckled SAR image to its low pass approximation, and is used to modulate high pass details extracted from the available Pan image by means of the á trous wavelet decomposition. Then, high pass details modulated with the texture is applied to obtain the fusion product by HPFM (High pass Filter-based Modulation) fusion method. A set of image data including co-registered Landsat TM, ENVISAT SAR and SPOT Pan is used for the experiment. The results demonstrate accurate spectral preservation on vegetated regions, bare soil, and also on textured areas (buildings and road network) where SAR texture information enhances the fusion product, and the proposed approach is effective for image interpret and classification.

SIMULATION OF SHIP GENERATED TURBULENT AND VORTICAL WAKE IMAGING BY SAR

Institute of Scientific and Technical Information of China (English)

Wang Aiming; Zhu Minhui

2004-01-01

Synthetic Aperture Radar (SAR) imaging of ocean surface features is studied. The simulation of the turbulent and vortical features generated by a moving ship and SAR imaging of these wakes is carried out. The turbulent wake damping the ocean surface capillary waves may be partially responsible for the suppression of surface waves near the ship track. The vortex pair generating a change in the lateral flow field behind the ship may be partially responsible for an enhancement of the waves near the edges of the smooth area. These hydrodynamic phenomena as well as the changes of radar backscatter generated by turbulence and vortex are simulated.An SAR imaging model is then used on such ocean surface features to provide SAR images.Comparison of two ships' simulated SAR images shows that the wake features are different for various ship parameters.

Risk factors for chronic post-traumatic stress disorder (PTSD) in SARS survivors.

Science.gov (United States)

Mak, Ivan Wing Chit; Chu, Chung Ming; Pan, Pey Chyou; Yiu, Michael Gar Chung; Ho, Suzanne C; Chan, Veronica Lee

2010-01-01

Post-traumatic stress disorder (PTSD) is one of the most prevalent long-term psychiatric diagnoses among survivors of severe acute respiratory syndrome (SARS). The objective of this study was to identify the predictors of chronic PTSD in SARS survivors. PTSD at 30 months after the SARS outbreak was assessed by the Structured Clinical Interview for the DSM-IV. Survivors' demographic data, medical information and psychosocial variables were collected for risk factor analysis. Multivariate logistic regression analysis showed that female gender as well as the presence of chronic medical illnesses diagnosed before the onset of SARS and avascular necrosis were independent predictors of PTSD at 30 months post-SARS. Associated factors included higher-chance external locus of control, higher functional disability and higher average pain intensity. The study of PTSD at 30 months post-SARS showed that the predictive value of acute medical variables may fade out. Our findings do not support some prior hypotheses that the use of high dose corticosteroids is protective against the development of PTSD. On the contrary, the adversity both before and after the SARS outbreak may be more important in hindering recovery from PTSD. The risk factor analysis can not only improve the detection of hidden psychiatric complications but also provide insight for the possible model of care delivery for the SARS survivors. With the complex interaction of the biopsychosocial challenges of SARS, an integrated multidisciplinary clinic setting may be a superior approach in the long-term management of complicated PTSD cases. Copyright © 2010 Elsevier Inc. All rights reserved.

Is Video Podcast Supplementation as a Learning Aid Beneficial to Dental Students?

Science.gov (United States)

Kalludi, Shivananda; Punja, Dhiren; Rao, Raghavendra; Dhar, Murali

2015-12-01

Podcasting has recently emerged as an important information technology tool for health professionals. Podcasts can be viewed online or downloaded to a user computer or a handheld multimedia device like a portable MP3 player, smart phone and tablet device. The principal advantage of the podcast is that the presentation of information need not be linked with any particular time or location. Since students are familiar with newer technology tools and may be using it on a regular basis, video podcast could serve as a convenient tool for students to help remember both conceptual and factual information. The purpose of this study was to assess the attitude of first year dental students towards video podcast supplementation and to assess the efficacy of video podcast as a teaching aid in comparison to text book reading. First year dental students were recruited for this study. A didactic lecture class was conducted for the students (n=100). The students were then randomly divided into two groups. Students present in group A (n=46) underwent a video podcast session followed by a multiple choice question test. This was followed by student feedback to assess the usefulness of video podcast. Students belonging to group B (n=54) had a study session for 20 minutes followed by the MCQ test. Students then underwent the video podcast session followed by feedback to assess the utility of video podcast. Mann-Whitney U test was applied to compare the difference in the median MCQ score between the two groups. The findings revealed a significant gain in the median MCQ score in the intervention group (group A) when compared to control group (Group B). In the feedback form, 89% of students agreed that the video podcast might be useful as it would enable them to view slides and hear the lectures repeatedly. Students who underwent the video podcast session performed significantly better in the MCQ test compared to students who underwent text book reading alone. This demonstrates an

SAR Cross-Ambiguities in SAOCOM-CS Large Baseline Bistatic Configuration

OpenAIRE

Bordoni, Federica; Rodriguez-Cassola, Marc; Younis, Marwan; Prats-Iraola, Pau; Lopez-Dekker, Paco; Krieger, Gerhard

2016-01-01

The evaluation of the ambiguous signal level, the Ambiguity-to-Signal Ratio (ASR), plays a key role in the Synthetic Aperture Radar (SAR) design and performance prediction. In conventional SAR acquisition scenarios, the computation of the ASR is based on the evaluation of the range and azimuth ambiguous contributes. Though appealing for its simplicity, this approach could be inaccurate in case of complex SAR acquisition geometries. In this paper we focus on the ASR performance of the SAOCOM-...

Rice Crop Monitoring and Yield Estimation Through Cosmo Skymed and TerraSAR-X: A SAR-Based Experience in India

OpenAIRE

Pazhanivelan, S.; Kannan, P.; Christy Nirmala Mary, P.; Subramanian, E.; Jeyaraman, S.; Nelson, A.; Setiyono, T.; Holecz, F.; Barbieri, M.; Yadav, M.

2015-01-01

Rice is the most important cereal crop governing food security in Asia. Reliable and regular information on the area under rice production is the basis of policy decisions related to imports, exports and prices which directly affect food security. Recent and planned launches of SAR sensors coupled with automated processing can provide sustainable solutions to the challenges on mapping and monitoring rice systems. High resolution (3m) Synthetic Aperture Radar (SAR) imageries were used...

Integrating interferometric SAR data with levelling measurements of land subsidence using geostatistics

NARCIS (Netherlands)

Zhou, Y.; Stein, A.; Molenaar, M.

2003-01-01

Differential Synthetic Aperture Radar (SAR) interferometric (D-InSAR) data of ground surface deformation are affected by several error sources associated with image acquisitions and data processing. In this paper, we study the use of D-InSAR for quantifying land subsidence due to groundwater

Bats and SARS

Centers for Disease Control (CDC) Podcasts

2006-11-08

Bats are a natural reservoir for emerging viruses, among them henipaviruses and rabies virus variants. Dr. Nina Marano, Chief, Geographic Medicine and Health Promotion Branch, Division of Global Migration and Quarantine, CDC, explains connection between horseshoe bats and SARS coronavirus transmission.  Created: 11/8/2006 by Emerging Infectious Diseases.   Date Released: 11/17/2006.

More than Red Ribbons: AIDS Plays and Schools.

Science.gov (United States)

Sheppard, Mark

1995-01-01

Describes how the inclusion of a scene from Steven Deitz's play "Lonely Planet" can touch those who have lost friends to AIDS. Relates how a group of students went to see a production of "Falsettos" which provided an opportunity for the students to examine their own attitudes about homosexuality and AIDS. (PA)

G0-WISHART Distribution Based Classification from Polarimetric SAR Images

Science.gov (United States)

Hu, G. C.; Zhao, Q. H.

2017-09-01

Enormous scientific and technical developments have been carried out to further improve the remote sensing for decades, particularly Polarimetric Synthetic Aperture Radar(PolSAR) technique, so classification method based on PolSAR images has getted much more attention from scholars and related department around the world. The multilook polarmetric G0-Wishart model is a more flexible model which describe homogeneous, heterogeneous and extremely heterogeneous regions in the image. Moreover, the polarmetric G0-Wishart distribution dose not include the modified Bessel function of the second kind. It is a kind of simple statistical distribution model with less parameter. To prove its feasibility, a process of classification has been tested with the full-polarized Synthetic Aperture Radar (SAR) image by the method. First, apply multilook polarimetric SAR data process and speckle filter to reduce speckle influence for classification result. Initially classify the image into sixteen classes by H/A/α decomposition. Using the ICM algorithm to classify feature based on the G0-Wshart distance. Qualitative and quantitative results show that the proposed method can classify polaimetric SAR data effectively and efficiently.

The Generalized Gamma-DBN for High-Resolution SAR Image Classification

Directory of Open Access Journals (Sweden)

Zhiqiang Zhao

2018-06-01

Full Text Available With the increase of resolution, effective characterization of synthetic aperture radar (SAR image becomes one of the most critical problems in many earth observation applications. Inspired by deep learning and probability mixture models, a generalized Gamma deep belief network (g Γ-DBN is proposed for SAR image statistical modeling and land-cover classification in this work. Specifically, a generalized Gamma-Bernoulli restricted Boltzmann machine (gΓB-RBM is proposed to capture high-order statistical characterizes from SAR images after introducing the generalized Gamma distribution. After stacking the g Γ B-RBM and several standard binary RBMs in a hierarchical manner, a gΓ-DBN is constructed to learn high-level representation of different SAR land-covers. Finally, a discriminative neural network is constructed by adding an additional predict layer for different land-covers over the constructed deep structure. Performance of the proposed approach is evaluated via several experiments on some high-resolution SAR image patch sets and two large-scale scenes which are captured by ALOS PALSAR-2 and COSMO-SkyMed satellites respectively.

a Statistical Texture Feature for Building Collapse Information Extraction of SAR Image

Science.gov (United States)

Li, L.; Yang, H.; Chen, Q.; Liu, X.

2018-04-01

Synthetic Aperture Radar (SAR) has become one of the most important ways to extract post-disaster collapsed building information, due to its extreme versatility and almost all-weather, day-and-night working capability, etc. In view of the fact that the inherent statistical distribution of speckle in SAR images is not used to extract collapsed building information, this paper proposed a novel texture feature of statistical models of SAR images to extract the collapsed buildings. In the proposed feature, the texture parameter of G0 distribution from SAR images is used to reflect the uniformity of the target to extract the collapsed building. This feature not only considers the statistical distribution of SAR images, providing more accurate description of the object texture, but also is applied to extract collapsed building information of single-, dual- or full-polarization SAR data. The RADARSAT-2 data of Yushu earthquake which acquired on April 21, 2010 is used to present and analyze the performance of the proposed method. In addition, the applicability of this feature to SAR data with different polarizations is also analysed, which provides decision support for the data selection of collapsed building information extraction.

Multi-Pixel Simultaneous Classification of PolSAR Image Using Convolutional Neural Networks

Science.gov (United States)

Xu, Xin; Gui, Rong; Pu, Fangling

2018-01-01

Convolutional neural networks (CNN) have achieved great success in the optical image processing field. Because of the excellent performance of CNN, more and more methods based on CNN are applied to polarimetric synthetic aperture radar (PolSAR) image classification. Most CNN-based PolSAR image classification methods can only classify one pixel each time. Because all the pixels of a PolSAR image are classified independently, the inherent interrelation of different land covers is ignored. We use a fixed-feature-size CNN (FFS-CNN) to classify all pixels in a patch simultaneously. The proposed method has several advantages. First, FFS-CNN can classify all the pixels in a small patch simultaneously. When classifying a whole PolSAR image, it is faster than common CNNs. Second, FFS-CNN is trained to learn the interrelation of different land covers in a patch, so it can use the interrelation of land covers to improve the classification results. The experiments of FFS-CNN are evaluated on a Chinese Gaofen-3 PolSAR image and other two real PolSAR images. Experiment results show that FFS-CNN is comparable with the state-of-the-art PolSAR image classification methods. PMID:29510499

Effects of two educational method of lecturing and role playing on knowledge and performance of high school students in first aid at emergency scene.

Science.gov (United States)

Hassanzadeh, Akbar; Vasili, Arezu; Zare, Zahra

2010-01-01

This study aimed to investigate the effects of two educational methods on students' knowledge and performance regarding first aid at emergency scenes. In this semi-experimental study, the sample was selected randomly among male and female public high school students of Isfahan. Each group included 60 students. At first the knowledge and performance of students in first aid at emergency scene was assessed using a researcher-made questionnaire. Then necessary education was provided to the students within 10 sessions of two hours by lecturing and role playing. The students' knowledge and performance was as-sessed again and the results were compared. It was no significant relationship between the frequency distribution of students' age, major and knowledge and performance before the educational course in the two groups. The score of knowledge in performing CPR, using proper way to bandage, immobilizing the injured area, and proper ways of carrying injured person after the education was significantly increased in both groups. Moreover, the performance in proper way to bandage, immobilizing injured area and proper ways of carrying injured person after educational course was significantly higher in playing role group compared to lecturing group after education. Iran is a developing country with a young generation and it is a country with high risk of natural disasters; so, providing necessary education with more effective methods can be effective in reducing mortality and morbidity due to lack of first aid care in crucial moments. Training with playing role is suggested for this purpose.

Evaluation of Polarimetric SAR Decomposition for Classifying Wetland Vegetation Types

Directory of Open Access Journals (Sweden)

Sang-Hoon Hong

2015-07-01

Full Text Available The Florida Everglades is the largest subtropical wetland system in the United States and, as with subtropical and tropical wetlands elsewhere, has been threatened by severe environmental stresses. It is very important to monitor such wetlands to inform management on the status of these fragile ecosystems. This study aims to examine the applicability of TerraSAR-X quadruple polarimetric (quad-pol synthetic aperture radar (PolSAR data for classifying wetland vegetation in the Everglades. We processed quad-pol data using the Hong & Wdowinski four-component decomposition, which accounts for double bounce scattering in the cross-polarization signal. The calculated decomposition images consist of four scattering mechanisms (single, co- and cross-pol double, and volume scattering. We applied an object-oriented image analysis approach to classify vegetation types with the decomposition results. We also used a high-resolution multispectral optical RapidEye image to compare statistics and classification results with Synthetic Aperture Radar (SAR observations. The calculated classification accuracy was higher than 85%, suggesting that the TerraSAR-X quad-pol SAR signal had a high potential for distinguishing different vegetation types. Scattering components from SAR acquisition were particularly advantageous for classifying mangroves along tidal channels. We conclude that the typical scattering behaviors from model-based decomposition are useful for discriminating among different wetland vegetation types.

SAR11 Bacteria: The Most Abundant Plankton in the Oceans.

Science.gov (United States)

Giovannoni, Stephen J

2017-01-03

SAR11 is a group of small, carbon-oxidizing bacteria that reach a global estimated population size of 2.4×10 28 cells-approximately 25% of all plankton. They are found throughout the oceans but reach their largest numbers in stratified, oligotrophic gyres, which are an expanding habitat in the warming oceans. SAR11 likely had a Precambrian origin and, over geological time, evolved into the niche of harvesting labile, low-molecular-weight dissolved organic matter (DOM). SAR11 cells are minimal in size and complexity, a phenomenon known as streamlining that is thought to benefit them by lowering the material costs of replication and maximizing transport functions that are essential to competition at ultralow nutrient concentrations. One of the surprises in SAR11 metabolism is their ability to both oxidize and produce a variety of volatile organic compounds that can diffuse into the atmosphere. SAR11 cells divide slowly and lack many forms of regulation commonly used by bacterial cells to adjust to changing environmental conditions. As a result of genome reduction, they require an unusual range of nutrients, which leads to complex biochemical interactions with other plankton. The study of SAR11 is providing insight into the biogeochemistry of labile DOM and is affecting microbiology beyond marine science by providing a model for understanding the evolution and function of streamlined cells.

Multi-temporal and Dual-polarization Interferometric SAR for Land Cover Type Classification

Directory of Open Access Journals (Sweden)

WANG Xinshuang

2015-05-01

Full Text Available In order to study SAR land cover classification method, this paper uses the multi-dimensional combination of temporal,polarization and InSAR data. The area covered by space borne data of ALOS PALSAR in Xunke County,Heilongjiang Province was chosen as test site. A land cover classification technique of SVM based on multi-temporal, multi-polarization and InSAR data had been proposed, using the sensitivity to land cover type of multi-temporal, multi-polarization SAR data and InSAR measurements, and combing time series characteristic of backscatter coefficient and correlation coefficient to identify ground objects. The results showed the problem of confusion between forest land and urban construction land can be nicely solved, using the correlation coefficient between HH and HV, and also combing the selected temporal, polarization and InSAR characteristics. The land cover classification result with higher accuracy is gotten using the classification algorithm proposed in this paper.

New free Danish online (Q)SAR predictions database with >600,000 substances

DEFF Research Database (Denmark)

Wedebye, Eva Bay; Dybdahl, Marianne; Reffstrup, Trine Klein

Since 2005 the Danish (Q)SAR Database has been freely available on the Internet. It is a tool that allows single chemical substance profiling and screenings based on predicted hazard information. The database is also included in the OECD (Q)SAR Application Toolbox which is used worldwide...... by regulators and industry. A lot of progress in (Q)SAR model development, application and documentation has been made since the publication in 2005. A new and completely rebuild online (Q)SAR predictions database was therefore published in November 2015 at http://qsar.food.dtu.dk. The number of chemicals...... in the database has been expanded from 185,000 to >600,000. As far as possible all organic single constituent substances that were pre-registered under REACH have been included in the new structure set. The new Danish (Q)SAR Database includes estimates from more than 200 (Q)SARs covering a wide range of hazardous...

What is missing? An operational inundation mapping framework by SAR data

Science.gov (United States)

Shen, X.; Anagnostou, E. N.; Zeng, Z.; Kettner, A.; Hong, Y.

2017-12-01

Compared to optical sensors, synthetic aperture radar (SAR) works all-day all-weather. In addition, its spatial resolution does not decrease with the height of the platform and is thus applicable to a range of important studies. However, existing studies did not address the operational demands of real-time inundation mapping. The direct proof is that no water body product exists for any SAR-based satellites. Then what is missing between science and products? Automation and quality. What makes it so difficult to develop an operational inundation mapping technique based on SAR data? Spectrum-wise, unlike optical water indices such as MNDWI, AWEI etc., where a relative constant threshold may apply across acquisition of images, regions and sensors, the threshold to separate water from non-water pixels in each SAR images has to be individually chosen. The optimization of the threshold is the first obstacle to the automation of the SAR data algorithm. Morphologically, the quality and reliability of the results have been compromised by over-detection caused by smooth surface and shadowing area, the noise-like speckle and under-detection caused by strong-scatter disturbance. In this study, we propose a three-step framework that addresses all aforementioned issues of operational inundation mapping by SAR data. The framework consists of 1) optimization of Wishart distribution parameters of single/dual/fully-polarized SAR data, 2) morphological removal of over-detection, and 3) machine-learning based removal of under-detection. The framework utilizes not only the SAR data, but also the synergy of digital elevation model (DEM), and optical sensor-based products of fine resolution, including the water probability map, land cover classification map (optional), and river width. The framework has been validated throughout multiple areas in different parts of the world using different satellite SAR data and globally available ancillary data products. Therefore, it has the potential

Comparing satellite SAR and wind farm wake models

DEFF Research Database (Denmark)

Hasager, Charlotte Bay; Vincent, P.; Husson, R.

2015-01-01

. These extend several tens of kilometres downwind e.g. 70 km. Other SAR wind maps show near-field fine scale details of wake behind rows of turbines. The satellite SAR wind farm wake cases are modelled by different wind farm wake models including the PARK microscale model, the Weather Research and Forecasting...... (WRF) model in high resolution and WRF with coupled microscale parametrization....

Genomic characterization of two novel SAR11 isolates from the Red Sea, including the first strain of the SAR11 Ib clade.

Science.gov (United States)

Jimenez-Infante, Francy; Ngugi, David Kamanda; Vinu, Manikandan; Blom, Jochen; Alam, Intikhab; Bajic, Vladimir B; Stingl, Ulrich

2017-07-01

The SAR11 clade (Pelagibacterales) is a diverse group that forms a monophyletic clade within the Alphaproteobacteria, and constitutes up to one third of all prokaryotic cells in the photic zone of most oceans. Pelagibacterales are very abundant in the warm and highly saline surface waters of the Red Sea, raising the question of adaptive traits of SAR11 populations in this water body and warmer oceans through the world. In this study, two pure cultures were successfully obtained from surface waters on the Red Sea: one isolate of subgroup Ia and one of the previously uncultured SAR11 Ib lineage. The novel genomes were very similar to each other and to genomes of isolates of SAR11 subgroup Ia (Ia pan-genome), both in terms of gene content and synteny. Among the genes that were not present in the Ia pan-genome, 108 (RS39, Ia) and 151 genes (RS40, Ib) were strain specific. Detailed analyses showed that only 51 (RS39, Ia) and 55 (RS40, Ib) of these strain-specific genes had not reported before on genome fragments of Pelagibacterales. Further analyses revealed the potential production of phosphonates by some SAR11 members and possible adaptations for oligotrophic life, including pentose sugar utilization and adhesion to marine particulate matter. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

TOWARDS CHANGE DETECTION IN URBAN AREA BY SAR INTERFEROMETRY AND RADARGRAMMETRY

Directory of Open Access Journals (Sweden)

C. Dubois

2013-04-01

Full Text Available Change detection in urban area is an active topic in remote sensing. However, well-dealt subject in optical remote sensing, this research topic is still at an early stage and needs deeper investigations and improvement in what concerns SAR and InSAR remote sensing. Due to their weather and daylight-independency, SAR sensors allow an all-time observation of the earth. This is determining in cases where rapid change detection is required after a natural – or technological – disaster. Due to the high resolution that can be achieved, the new generation of space-borne radar sensors opens up new perspectives for analysing buildings in urban areas. Moreover, due to their short revisiting cycle, they give rise to monitoring and change detection applications. In this paper, we present a concept for change detection in urban area at building level, relying only on SAR- and InSAR data. In this approach, interferometric and radargrammetric SAR data are merged in order to detect changes. Here, we present the overall workflow, the test area, the required data as well as first findings on the best-suited stereo-configurations for change detection.

Evaluating the Effectiveness of Mental Health First Aid Training among Student Affairs Staff at a Canadian University

Science.gov (United States)

Massey, Jennifer; Brooks, Meghan; Burrow, Jeff

2014-01-01

This study evaluates the effectiveness of providing the Mental Health First Aid training program to student affairs staff. The objective of the training was to increase knowledge of mental health, enhance sensitivity, and raise confidence to intervene and assist individuals experiencing a mental health issue. We found the training successfully met…

"If you don't abstain, you will die of AIDS": AIDS education in Kenyan public schools.

Science.gov (United States)

Njue, Carolyne; Nzioka, Charles; Ahlberg, Beth-Maina; Pertet, Anne M; Voeten, Helene A C M

2009-04-01

We explored constraints of implementing AIDS education in public schools in Kenya. Sixty interviews with teachers and 60 focus group discussions with students were conducted in 21 primary and nine secondary schools. System/school-level constraints included lack of time in the curriculum, limited reach of secondary-school students (because AIDS education is embedded in biology, which is not compulsory), and disapproval of openness about sex and condoms by the Ministry of Education and parents. Alternative strategies to teach about AIDS had their own constraints. Teachers lacked training and support and felt uncomfortable with the topic. They were not used to interactive teaching methods and sometimes breached confidentiality. Teachers' negative attitudes constrained students from seeking information. Training interventions should be provided to teachers to increase their self-confidence, foster more positive attitudes, and stimulate interactive teaching methods. The Ministry of Education needs to have a clear policy toward the promotion of condoms.

SAR China Land Mapping Project: Development, Production and Potential Applications

International Nuclear Information System (INIS)

Zhang, Lu; Guo, Huadong; Liu, Guang; Fu, Wenxue; Yan, Shiyong; Song, Rui; Ji, Peng; Wang, Xinyuan

2014-01-01

Large-area, seamless synthetic aperture radar (SAR) mosaics can reflect overall environmental conditions and highlight general trends in observed areas from a macroscopic standpoint, and effectively support research at the global scale, which is in high demand now across scientific fields. The SAR China Land Mapping Project (SCLM), supported by the Digital Earth Science Platform Project initiated and managed by the Center for Earth Observation and Digital Earth, Chinese Academy of Sciences (CEODE), is introduced in this paper. This project produced a large-area SAR mosaic dataset and generated the first complete seamless SAR map covering the entire land area of China using EnviSat-ASAR images. The value of the mosaic map is demonstrated by some potential applications in studies of urban distribution, rivers and lakes, geologic structures, geomorphology and paleoenvironmental change

Vegetation Parameter Extraction Using Dual Baseline Polarimetric SAR Interferometry Data

Science.gov (United States)

Zhang, H.; Wang, C.; Chen, X.; Tang, Y.

2009-04-01

For vegetation parameter inversion, the single baseline polarimetric SAR interferometry (POLinSAR) technique, such as the three-stage method and the ESPRIT algorithm, is limited by the observed data with the minimum ground to volume amplitude ration, which effects the estimation of the effective phase center for the vegetation canopy or the surface, and thus results in the underestimated vegetation height. In order to remove this effect of the single baseline inversion techniques in some extend, another baseline POLinSAR data is added on vegetation parameter estimation in this paper, and a dual baseline POLinSAR technique for the extraction of the vegetation parameter is investigated and improved to reduce the dynamic bias for the vegetation parameter estimation. Finally, the simulated data and real data are used to validate this dual baseline technique.

Exploring cloud and big data components for SAR archiving and analysis

Science.gov (United States)

Baker, S.; Crosby, C. J.; Meertens, C.; Phillips, D.

2017-12-01

Under the Geodesy Advancing Geoscience and EarthScope (GAGE) NSF Cooperative Agreement, UNAVCO has seen the volume of the SAR Data Archive grow at a substantial rate, from 2 TB in Y1 and 5 TB in Y2 to 41 TB in Y3 primarily due to WInSAR PI proposal management of ALOS-­2/JAXA (Japan Aerospace Exploration Agency) data and to a lesser extent Supersites and other data collections. JAXA provides a fixed number of scenes per year for each PI, and some data files are 50­-60GB each, which accounts for the large volume of data. In total, over 100TB of SAR data are in the WInSAR/UNAVCO archive and a large portion of these are available unrestricted for WInSAR members. In addition to the existing data, newer data streams from the Sentinel-1 and NISAR missions will require efficient processing pipelines and easily scalable infrastructure to handle processed results. With these growing data sizes and space concerns, the SAR archive operations migrated to the Texas Advanced Computing Center (TACC) via an NSF XSEDE proposal in spring 2017. Data are stored on an HPC system while data operations are running on Jetstream virtual machines within the same datacenter. In addition to the production data operations, testing was done in early 2017 with container based InSAR processing analysis using JupyterHub and Docker images deployed on a VM cluster on Jetstream. The JupyterHub environment is well suited for short courses and other training opportunities for the community such as labs for university courses on InSAR. UNAVCO is also exploring new processing methodologies using DC/OS (the datacenter operating system) for batch and stream processing workflows and time series analysis with Big Data open source components like the Spark, Mesos, Akka, Cassandra, Kafka (SMACK) stack. The comparison of the different methodologies will provide insight into the pros and cons for each and help the SAR community with decisions about infrastructure and software requirements to meet their research

Calibration of SAR probes in waveguide at 900 MHz

International Nuclear Information System (INIS)

Jokela, K.; Puranen, L.; Hyysalo, P.

1998-01-01

The radiation safety tests for hand-held mobile phones require precise calibration of the small electric field probes used for the measurement of SAR in phantoms simulating the human body. In this study a calibration based on a rectangular waveguide was developed for SAR calibrations at 900 MHz

Project PHARUS: Towards a polarimetric C-band airborne SAR

NARCIS (Netherlands)

Hoogeboom, P.; Koomen, P.J.; Otten, M.P.G.; Pouwels, H.; Snoeij, P.

1989-01-01

A few years ago three institutes in the Netherlands developed a plan to design and build a polarimetric C-band aircraft SAR system of a novel design, called PHARUS (PHased Array Universal SAR), meant as a replacement for our current digital SLAR system. These institutes are the Physics and

A comparison between the effect of training performed by teachers and by health staff on the knowledge of high school students about AIDS in Bushehr/Iran

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Sherafat Akaberian

2005-02-01

Full Text Available A.I.D.S as a worldwide crisis continues to spread in Iran too. The number of afflicted patients has reached 5780 subjects most of them are between 20 to 40 years of age. Prevention is one of the most effective methods to combat this human hazard. Promotion of general knowledge is thought to be the preliminary measure in this regard. Although, schools have turned to be the most favorable environment for health education, the issue of the group to afford training has remained controversial in our country yet. The aim of this research is a comparison between the effect of training performed by teachers or health staff on the knowledge of students of the first high school grade in Bushehr/ Iran. A total of 684 male and female students of the first high school grade were selected according to cluster random sampling. The selected students were divided into two groups and training for A.I.D.S using the same contents was done by their teachers and health staff separately. Before intervention, the mean knowledge scores of female & male students about A.I.D.S were 16.68 and 15.52, respectively. There was no significant difference in female students in two groups but teacher trained male students showed an increment score of 4.17 while in health staff ones, the score increment was 2.22 (P<0.01. In conclusion, the level of knowledge about A.I.D.S was not satisfactory in the high school students in Bushehr and for education in this group their sex in conjunction to different training methods should be considered.

Relationship between Teachers' Motivation Teaching HIV/AIDS Education and Students' Knowledge and Attitude towards Sexual Behaviour in Secondary Schools in Coast Region, Kenya

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Thuo, Daniel Njane; Nyaga, Veronica K.; Bururia, David N.; Barchok, Hilary K.

2016-01-01

Education plays an important role in curbing the spread of HIV and AIDS among the youth. However, there is little known how teachers' motivation in teaching HIV/AIDS education affects students' knowledge and attitudes towards sexual behaviour. The purpose of the study was to determine the relationship between teachers' level of motivation in…

Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine

International Nuclear Information System (INIS)

Zhao Ping; Cao Jie; Zhao Lanjuan; Qin Zhaolin; Ke Jinshan; Pan Wei; Ren Hao; Yu Jianguo; Qi Zhongtian

2005-01-01

The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DH5α and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobulins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD8 + CTL responses to N protein. The study shows that N protein of SARS-CoV not only is an important B cell immunogen, but also can elicit broad-based cellular immune responses. The results indicate that the N protein may be of potential value in vaccine development for specific prophylaxis and treatment against SARS

Change Detection with Polarimetric SAR Imagery for Nuclear Verification

International Nuclear Information System (INIS)

Canty, M.

2015-01-01

This paper investigates the application of multivariate statistical change detection with high-resolution polarimetric SAR imagery acquired from commercial satellite platforms for observation and verification of nuclear activities. A prototype software tool comprising a processing chain starting from single look complex (SLC) multitemporal data through to change detection maps is presented. Multivariate change detection algorithms applied to polarimetric SAR data are not common. This is because, up until recently, not many researchers or practitioners have had access to polarimetric data. However with the advent of several spaceborne polarimetric SAR instruments such as the Japanese ALOS, the Canadian Radarsat-2, the German TerraSAR-X, the Italian COSMO-SkyMed missions and the European Sentinal SAR platform, the situation has greatly improved. There is now a rich source of weather-independent satellite radar data which can be exploited for Nuclear Safeguards purposes. The method will also work for univariate data, that is, it is also applicable to scalar or single polarimetric SAR data. The change detection procedure investigated here exploits the complex Wishart distribution of dual and quad polarimetric imagery in look-averaged covariance matrix format in order to define a per-pixel change/no-change hypothesis test. It includes approximations for the probability distribution of the test statistic, and so permits quantitative significance levels to be quoted for change pixels. The method has been demonstrated previously with polarimetric images from the airborne EMISAR sensor, but is applied here for the first time to satellite platforms. In addition, an improved multivariate method is used to estimate the so-called equivalent number of looks (ENL), which is a critical parameter of the hypothesis test. (author)

Comparison of Sexual Knowledge, Attitude, and Behavior between Female Chinese College Students from Urban Areas and Rural Areas: A Hidden Challenge for HIV/AIDS Control in China.

Science.gov (United States)

Chen, Min; Liao, Yong; Liu, Jia; Fang, Wenjie; Hong, Nan; Ye, Xiaofei; Li, Jianjun; Tang, Qinglong; Pan, Weihua; Liao, Wanqing

2016-01-01

Currently, research in sexual behavior and awareness in female Chinese college students (FCCSs) is limited, particularly regarding the difference and the influencing factors between students from rural areas and urban areas. To fill the gap in available data, a cross-sectional study using anonymous questionnaires was conducted among 3193 female students from six universities located in Beijing, Shanghai, and Guangzhou, China, from February to June, 2013. Of the 2669 respondents, 20.6% and 20.9% of the students from urban and rural areas, respectively, reported being sexually experienced. The proportion of students who received safe-sex education prior to entering university from rural areas (22.4%, 134/598) was lower ( P knowledge concerning human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) transmission and the risks is insufficient, particularly for those from rural areas, which is a challenge for HIV/AIDS control in China. The Chinese government should establish more specific HIV/AIDS prevention policies for Chinese young women, strengthen sex education, and continue to perform relevant research.

SAR Agriculture Rice Production Estimation (SARPE)

Science.gov (United States)

Raimadoya, M.

2013-12-01

The study of SAR Agriculture Rice Production Estimation (SARPE) was held in Indonesia on 2012, as part of Asia-Rice Crop Estimation & Monitoring (Asia-RiCE), which is a component for the GEO Global Agricultural Monitoring (GEOGLAM) initiative. The study was expected to give a breakthrough result, by using radar technology and paradigm shift of the standard production estimation system from list frame to area frame approach. This initial product estimation system is expected to be refined (fine tuning) in 2013, by participating as part of Technical Demonstration Site (Phase -1A) of Asia-RICE. The implementation period of this initial study was from the date of March 12 to December 10, 2012. The implementation of the study was done by following the approach of the BIMAS-21 framework, which has been developed since 2008. The results of this study can be briefly divided into two major components, namely: Rice-field Baseline Mapping (PESBAK - Peta Sawah Baku) and Crop Growth Monitoring. Rice-fields were derived from the mapping results of the Ministry of Agriculture (Kemtan), and validated through Student Extension Campaign of the Faculty of Agriculture, Bogor Agricultural University (IPB). While for the crop growth, it was derived from the results of image analysis process. The analysis was done, either on radar/Radarsat-2 (medium resolution) or optical/ MODIS (low resolution), based on the Planting Calendar (KATAM) of Kemtan. In this case, the planting season II/2012-2013 of rice production centers in West Java Province (Karawang, Subang and Indramayu counties). The selection of crop season and county were entirely dependent on the quality of the available PESBAK and procurement process of radar imagery. The PESBAK is still in the form of block instead of fields, so it can not be directly utilized in this study. Efforts to improve the PESBAK can not be optimal because the provided satellite image (ECW format) is not the original one. While the procurement process of

Target discrimination method for SAR images based on semisupervised co-training

Science.gov (United States)

Wang, Yan; Du, Lan; Dai, Hui

2018-01-01

Synthetic aperture radar (SAR) target discrimination is usually performed in a supervised manner. However, supervised methods for SAR target discrimination may need lots of labeled training samples, whose acquirement is costly, time consuming, and sometimes impossible. This paper proposes an SAR target discrimination method based on semisupervised co-training, which utilizes a limited number of labeled samples and an abundant number of unlabeled samples. First, Lincoln features, widely used in SAR target discrimination, are extracted from the training samples and partitioned into two sets according to their physical meanings. Second, two support vector machine classifiers are iteratively co-trained with the extracted two feature sets based on the co-training algorithm. Finally, the trained classifiers are exploited to classify the test data. The experimental results on real SAR images data not only validate the effectiveness of the proposed method compared with the traditional supervised methods, but also demonstrate the superiority of co-training over self-training, which only uses one feature set.

Implementing AIDS Education

Directory of Open Access Journals (Sweden)

Grace C. Huerta

1996-08-01

Full Text Available The world has been challenged by the AIDS epidemic for 15 years. In 1985, the U.S. Department of Health and Human Services, Centers for Disease Control, allocated funds to all state departments of education to assist schools in the development of AIDS education policies and programs. Yet, these policies do not ensure that all students receive effective AIDS education. On September 21, 1991, the Arizona Legislature passed Senate Bill 1396, which requires public schools to annually provide AIDS education in grades K-12. The bill was rescinded in 1995. With prohibitive curriculum guidelines, limited teacher training opportunities and tremendous instructional demands, this educational policy was implemented in disparate forms. By examining the perspectives of the Arizona educators (representing three school districts, this qualitative study reveals how teachers ultimately controlled the delivery and nature of AIDS instruction based upon personal values, views of teacher roles, and their interpretation of the mandate itself.

Investigation of the Capability of Compact Polarimetric SAR Interferometry to Estimate Forest Height

Science.gov (United States)

Zhang, Hong; Xie, Lei; Wang, Chao; Chen, Jiehong

2013-08-01

The main objective of this paper is to investigate the capability of compact Polarimetric SAR Interferometry (C-PolInSAR) on forest height estimation. For this, the pseudo fully polarimetric interferomteric (F-PolInSAR) covariance matrix is firstly reconstructed, then the three- stage inversion algorithm, hybrid algorithm, Music and Capon algorithm are applied to both C-PolInSAR covariance matrix and pseudo F-PolInSAR covariance matrix. The availability of forest height estimation is demonstrated using L-band data generated by simulator PolSARProSim and X-band airborne data acquired by East China Research Institute of Electronic Engineering, China Electronics Technology Group Corporation.

Evaluation of SLAR and simulated thematic mapper MSS data for forest cover mapping using computer-aided analysis techniques

Science.gov (United States)

Hoffer, R. M.; Dean, M. E.; Knowlton, D. J.; Latty, R. S.

1982-01-01

Kershaw County, South Carolina was selected as the study site for analyzing simulated thematic mapper MSS data and dual-polarized X-band synthetic aperture radar (SAR) data. The impact of the improved spatial and spectral characteristics of the LANDSAT D thematic mapper data on computer aided analysis for forest cover type mapping was examined as well as the value of synthetic aperture radar data for differentiating forest and other cover types. The utility of pattern recognition techniques for analyzing SAR data was assessed. Topics covered include: (1) collection and of TMS and reference data; (2) reformatting, geometric and radiometric rectification, and spatial resolution degradation of TMS data; (3) development of training statistics and test data sets; (4) evaluation of different numbers and combinations of wavelength bands on classification performance; (5) comparison among three classification algorithms; and (6) the effectiveness of the principal component transformation in data analysis. The collection, digitization, reformatting, and geometric adjustment of SAR data are also discussed. Image interpretation results and classification results are presented.

Social and structural vulnerability as a barrier in HIV and/or AIDS communication campaigns: Perceptions of undergraduate students at a South African tertiary institution

Directory of Open Access Journals (Sweden)

Olivia Kunguma

2018-03-01

Full Text Available The multicultural nature of a higher academic institution comprising students from different backgrounds can either negatively or positively influence student behaviour. Students might engage in high-risk practices, which in turn can make them vulnerable to HIV infection. Higher academic institutions are then tasked with finding strategies that can help to reduce this risk and vulnerability to HIV and/or AIDS. However, there are many issues and barriers, both from the institution and students, which can impede the success of any communication strategy. The University of the Free State’s main campus was selected for this study. A sample of 402 students from a total of 17 591 undergraduate students participated in the study. A structured questionnaire was randomly distributed to the undergraduate students. The sample was compiled across all faculties, as well as on campus and off campus. A transact walk on campus with an observation checklist was also used for triangulation purposes. The observation checklist helped to collect data on the visibility of male and female condoms in toilet facilities, and HIV and/or AIDS information on noticeboards, bins, stationery, billboards, etc. The main finding indicated that students were not knowledgeable about HIV and/or AIDS campaigns rolled out on campus. To support this, the observational transact walk results indicated that there were no visible campaigns on campus. Also, problems with existing communication and organisational barriers were found not only with the students but also with the implementation office. This study recommends that the university needs to engage with the students by identifying the root cause of their vulnerability. The university should explore and make use of all the available resources for a successful intervention, thereby building students’ resilience in preventing HIV infection.

School-Based First Aid Training Programs: A Systematic Review

Science.gov (United States)

Reveruzzi, Bianca; Buckley, Lisa; Sheehan, Mary

2016-01-01

Background: This review examines the breadth of first aid training delivered to school students and the components that are age appropriate to adolescents. Method: Eligible studies included school-based first aid interventions targeting students aged between 10 and 18 years. Online databases were searched, for peer-reviewed publications available…

Information theoretic bounds for compressed sensing in SAR imaging

International Nuclear Information System (INIS)

Jingxiong, Zhang; Ke, Yang; Jianzhong, Guo

2014-01-01

Compressed sensing (CS) is a new framework for sampling and reconstructing sparse signals from measurements significantly fewer than those prescribed by Nyquist rate in the Shannon sampling theorem. This new strategy, applied in various application areas including synthetic aperture radar (SAR), relies on two principles: sparsity, which is related to the signals of interest, and incoherence, which refers to the sensing modality. An important question in CS-based SAR system design concerns sampling rate necessary and sufficient for exact or approximate recovery of sparse signals. In the literature, bounds of measurements (or sampling rate) in CS have been proposed from the perspective of information theory. However, these information-theoretic bounds need to be reviewed and, if necessary, validated for CS-based SAR imaging, as there are various assumptions made in the derivations of lower and upper bounds on sub-Nyquist sampling rates, which may not hold true in CS-based SAR imaging. In this paper, information-theoretic bounds of sampling rate will be analyzed. For this, the SAR measurement system is modeled as an information channel, with channel capacity and rate-distortion characteristics evaluated to enable the determination of sampling rates required for recovery of sparse scenes. Experiments based on simulated data will be undertaken to test the theoretic bounds against empirical results about sampling rates required to achieve certain detection error probabilities

Pixel Classification of SAR ice images using ANFIS-PSO Classifier

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G. Vasumathi

2016-12-01

Full Text Available Synthetic Aperture Radar (SAR is playing a vital role in taking extremely high resolution radar images. It is greatly used to monitor the ice covered ocean regions. Sea monitoring is important for various purposes which includes global climate systems and ship navigation. Classification on the ice infested area gives important features which will be further useful for various monitoring process around the ice regions. Main objective of this paper is to classify the SAR ice image that helps in identifying the regions around the ice infested areas. In this paper three stages are considered in classification of SAR ice images. It starts with preprocessing in which the speckled SAR ice images are denoised using various speckle removal filters; comparison is made on all these filters to find the best filter in speckle removal. Second stage includes segmentation in which different regions are segmented using K-means and watershed segmentation algorithms; comparison is made between these two algorithms to find the best in segmenting SAR ice images. The last stage includes pixel based classification which identifies and classifies the segmented regions using various supervised learning classifiers. The algorithms includes Back propagation neural networks (BPN, Fuzzy Classifier, Adaptive Neuro Fuzzy Inference Classifier (ANFIS classifier and proposed ANFIS with Particle Swarm Optimization (PSO classifier; comparison is made on all these classifiers to propose which classifier is best suitable for classifying the SAR ice image. Various evaluation metrics are performed separately at all these three stages.

77 FR 58819 - Notice of Submission for OMB Review; Federal Student Aid; William D. Ford Federal Direct Loan...

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2012-09-24

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2012-05-21

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Research on Strong Clutter Suppression for Gaofen-3 Dual-Channel SAR/GMTI

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Mingjie Zheng

2018-03-01

Full Text Available In spaceborne synthetic aperture radar (SAR, moving targets are almost buried in ground clutter due to the wide clutter Doppler spectrum and the restricted pulse repetition frequency (PRF, which increases the difficulty of moving target detection. Clutter suppression is one of the key issues in the spaceborne SAR moving target indicator operation. In this paper, we describe the clutter suppression principle and analyze the influence of amplitude and phase error on clutter suppression. In the following, a novel dual-channel SAR clutter suppression algorithm is proposed, which is suitable for the Gaofen-3(GF-3 SAR sensor. The proposed algorithm consists of three technique steps, namely adaptive two-dimensional (2D channel calibration, refined amplitude error correction and refined phase error correction. After channel error is corrected by these procedures, the clutter component, especially a strong clutter component, can be well suppressed. The validity of the proposed algorithm is verified by GF-3 SAR real data which demonstrates the ground moving-target indication (GMTI capability of GF-3 SAR sensor.

Advanced InSAR imaging for dune mapping

Science.gov (United States)

Havivi, Shiran; August, Yitzhak; Blumberg, Dan G.; Rotman, Stanley R.

2015-04-01

Aeolian morphologies are formed in the presence of sufficient wind energy and available particles. These processes occur naturally or are further enhanced or reduced by human intervention. The dimensions of change are dependent primarily on the wind energy and surface properties. Since the 1970's, remote sensing imagery both optical and radar, are used for documentation and interpretation of the geomorphologic changes of sand dunes. Remote sensing studies of Aeolian morphologies is mostly useful to document major changes, yet, subtle changes, occurring in a period of days or months in scales of centimeters, are very difficult to detect in imagery. Interferometric Synthetic Aperture Radar (InSAR) is an imaging technique for measuring Earth's surface topography and deformation. InSAR images are produced by measuring the radar phase difference between two separated antennas that view the same surface area. Classical InSAR is based on high coherence between two images or more. The output (interferogram) can show subtle changes with an accuracy of several millimeters to centimeters. Very little work has been done on measuring or identifying the changes in dunes using InSAR. The reason is that dunes tend to be less coherent than firm, stable, surfaces. This research aims to demonstrate how interferometric decorrelation, or, coherence change detection, can be used for identifying dune instability. We hypothesize and demonstrate that the loss of radar coherence over time on dunes can be used as an indication of the dune's instability. When SAR images are acquired at sufficiently close intervals one can measure the time it takes to lose coherence and associate this time with geomorphic stability. To achieve our goals, the Nitzanim coastal dunes along the Mediterranean, 40 km south of Tel-Aviv, Israel, were chosen as a case study. The dunes in this area are of varying levels of stability and vegetation cover and have been monitored meteorologically, geomorphologically and

Latitudinal dynamics of SAR-arcs relative to the local time

International Nuclear Information System (INIS)

Alekseev, V.N.; Ievenko, I.B.

1991-01-01

In November-December, 1988, January-April, 1989-1990, at the Maymaga station in Yakutia according to spectrophotometric data 47 events of the occurrence of red stable middle-latitudinal arcs (SAR-arcs) were recorded. On the basis of these data the latitudinal dynamics of SAR-arcs was studied depending on the local time and geomagnetic disturbance level. The uniform equatorial shift of SAR arcs in the night time is noticed, and a sharp increase of the speed of this motion can be caused by the nonstationary character of the magnetospheric activity

Alaska Synthetic Aperture Radar (SAR) Facility science data processing architecture

Science.gov (United States)

Hilland, Jeffrey E.; Bicknell, Thomas; Miller, Carol L.

1991-01-01

The paper describes the architecture of the Alaska SAR Facility (ASF) at Fairbanks, being developed to generate science data products for supporting research in sea ice motion, ice classification, sea-ice-ocean interaction, glacier behavior, ocean waves, and hydrological and geological study areas. Special attention is given to the individual substructures of the ASF: the Receiving Ground Station (RGS), the SAR Processor System, and the Interactive Image Analysis System. The SAR data will be linked to the RGS by the ESA ERS-1 and ERS-2, the Japanese ERS-1, and the Canadian Radarsat.

Wind mapping offshore in coastal Mediterranean area using SAR images

DEFF Research Database (Denmark)

Calaudi, Rosamaria; Arena, Felice; Badger, Merete

Satellite observations of the ocean surface from Synthetic Aperture Radars (SAR) provide information about the spatial wind variability over large areas. This is of special interest in the Mediterranean, where spatial wind information is only provided by sparse buoys, often with long periods...... of missing data. Here, we focus on evaluating the use of SAR for offshore wind mapping. Preliminary results from the analysis of SAR-based ocean winds in Mediterranean areas show interesting large scale wind flow features consistent with results from previous studies using numerical models and space borne...

LTE modem power consumption, SAR and RF signal strength emulation

DEFF Research Database (Denmark)

Musiige, Deogratius; Vincent, Laulagnet; Anton, François

2012-01-01

This paper presents a new methodology for emulating the LTE modem power consumption, emitted SAR and RF signal strength when transmitting an LTE signal. The inputs of the methodology are: modem logical/protocol commands, time advance, near-field specifier, and antenna characteristics. The power...... emulation model(s) are computed by a two layer 451 neural network based on physical power measurements. SAR is emulated by polynomial interpolation models based on FDTD simulations. The accuracies of the mathematical function approximations for the emulation models of power and SAR are 5.19% and 3...

Blood donors--Serious adverse reactions (SAR) 2010-2014 EFS Châteauroux, France.

Science.gov (United States)

Riga, A; Sapey, T; Bacanu, M; Py, J-Y; Dehaut, F

2015-06-01

In 2013, the national French incidence of serious adverse reactions (SAR) was 155.7 per 100,000 donations and 82% of SAR were grade 2 (French classification of SAR related to blood donors) The purpose of our study was to describe the profile of blood donator candidate which had a SAR in our center. The study contains all the SAR superior to grade 1 occurred on the site EFS Châteauroux (site and mobile blood collection) from January 2010 to October 31, 2014. We analyzed 37 parameters from the e-fit files (e-site French blood vigilance) and In-log software. We identified 82 SAR for 72,553 blood donations (incidence: 113.02 SAR per 100,000 donations). Forty-one men and 41 women, middle age 39 years (18-66). Average height: 1.68 m (1.49-1.85); average weight: 68 kg (50-98); body mass index (kg/m(2)): 24,13(18.6-31.9). All donors were Caucasian and 30% unemployed. We found 74 vasovagal syncope (VVS), 5 hematomas, 2 arterial injuries and an adverse reaction to citrate. In 90%, the SAR was immediate and of grade 2 in 85% of cases. Thirty-seven percent of SAR were first donation in connection with whole blood in 87% of cases. Regarding the seniority of donors, the number of average donations (whole blood, plasma, platelets) was 16.5. An SAR determined the stop of blood donation in 65% of cases with nearly 80% stoppage if it was a first donation. Seventy-three percent of SAR as a VVS took place during blood collection or within 5 minutes following the end of the donation. Sixty-one percent were men. Forty-four percent of cases were a first donation and 83% occurred in mobile blood collection. Average age was 36 years. The result was a permanent stop of all type of donations in 76% of cases. Twenty-seven percent of SAR as a VVS took place beyond 5 minutes after the end of the donation. Seventy-five percent were women. Thirty percent of cases were a first donation and 95% of SAR occurred in mobile blood collection. Average age was 42 years. The result was a permanent stop of