323 research outputs found
Ethical issues in the release of animals from captivity
For the general public, there is an intuitive appeal to an animal's living in the wild rather than in captivity. Rarely is it an appeal informed by careful scientific or ethical analysis, however. This paper discusses how animal release projects ought to be conducted, guided by the question, "what are the duties of humans toward animals that are to be released?" It studies the ethical responsibilities of caretakers, practical elements of a responsible release, and proper selection of candidate animals for release, and what marine science tells us about how best these requirements might be achieved
Large-scale Complex IT Systems
This paper explores the issues around the construction of large-scale complex
systems which are built as 'systems of systems' and suggests that there are
fundamental reasons, derived from the inherent complexity in these systems, why
our current software engineering methods and techniques cannot be scaled up to
cope with the engineering challenges of constructing such systems. It then goes
on to propose a research and education agenda for software engineering that
identifies the major challenges and issues in the development of large-scale
complex, software-intensive systems. Central to this is the notion that we
cannot separate software from the socio-technical environment in which it is
used.Comment: 12 pages, 2 figure
RDN-Include: Re-branding Remote Resources
The Resource Discovery Network (RDN) has developed tools that allow educational institutions and other organizations to access and display the output from its Web services with their own branding and look-and-feel. This paper describes the need for such tools and the architectural approach to their development. A potential application of this approach to the incorporation of news feeds is also given
Prevalence of HIV-1 Drug Resistance among Women Screening for HIV Prevention Trials in KwaZulu-Natal, South Africa (MTN-009)
Background:A major concern with using antiretroviral (ARV)-based products for HIV prevention is the potential spread of drug resistance, particularly from individuals who are HIV-infected but unaware of their status. Limited data exist on the prevalence of HIV infection or drug resistance among potential users of ARV-based prevention products.Methods:A cross-sectional study of reproductive-aged women who presented to screen for an HIV prevention trial was conducted at 7 clinical sites in Durban, South Africa. CD4+T cell counts, HIV-1 RNA levels and population sequencing of the protease and reverse transcriptase genes were performed for all women with 2 positive HIV rapid tests. Resistance mutations were identified using the Stanford Calibrated Population Resistance Tool.Results:Of the 1073 evaluable women, 400(37%) were confirmed as HIV-infected. Of those, plasma HIV-1 RNA was detectable in 365/400(91%) and undetectable(200 copies/ml) analyzed for drug resistance, 26(7.4%) had nucleoside reverse transcriptase inhibitor (NRTI), non-nucleoside reverse transcriptase inhibitor (NNRTI) or protease inhibitor (PI) drug resistance mutations. Among those with resistance, 18/26 participants(62%) had single-class NNRTI resistance and 5/26(19%) had dual-class NRTI/NNRTI. Major mutations in reverse transcriptase included K65R(n = 1), L74I(n = 1), K103N(n = 19), V106M(n = 4), Y181C(n = 2), M184V(n = 4), and K219E/R(n = 2). Major PI-resistance mutations were rare: M46L(n = 1) and I85V(n = 1). All participants were infected with subtype C virus, except one infected with subtype A.Conclusions:In women from Durban, South Africa screening for an HIV prevention trial, the HIV prevalence was high (37%) and HIV drug resistance prevalence was above 5%. This study highlights the potential challenges faced when implementing an ARV-based prevention product that overlaps with first-line antiretroviral therapy. Effective screening to exclude HIV infection among women interested in uptake of ARV-based HIV prevention will be essential in limiting the spread of ARV resistance
Motivating Persons with Schizophrenia to Exercise: Rationale and Design
Persons with schizophrenia spectrum disorders (SSDs) are not only at risk because of disabling disease symptoms but because necessary medications create health risks associated with high rates of obesity. Despite the well-known benefits of exercise, persons with SSDs rarely adhere to such regimens; few interventions to motivate exercise behavior have been tested in this group.
The purpose of this study is to examine effects of the Walk, Address sensations, Learn about exercise, Cue exercise behavior for persons with SSDs (WALC-S) motivational intervention upon exercise behavior. We will recruit a total of eighty outpatients 18–68 years, meeting these criteria: 1) chart diagnosis of schizophrenia, any subtype, schizoaffective disorder or schizophreniform disorder, according to the criteria described in the Diagnostic and Statistical Manual for Mental Disorders, 2) English speaking, 3) Stable medication regimen (defined as no medication changes within the last month), and 4) medical clearance for moderate exercise in writing from primary care provider. Participants will be randomly assigned to the experimental (4-week WALC-S motivational intervention), or the control group (4-week time and attention control). After the first 4 weeks, all participants will attend a 16-week walking group.
The primary measures of the effectiveness of the WALC-S are attendance, persistence and compliance to the 16-week walking group. The study will be completed in approximately January 2010. In addition to hypothesis testing, this study will provide information to estimate effect sizes to calculate power and determine appropriate sample sizes for future inquiries. This paper describes the rationale and design of the study
The Grizzly, February 13, 2003
Iraqi Speaker Describes his Country as a Prison of Suffering • Ursinus Student Heroes 30 Years Ago • To Fight or not to Fight: You May not Have the Option • Opinions: Skiing Fun Close to Home; Lonely this Valentine\u27s Day? • Female Pride, Guerrilla Warfare • First of Pew Fellows Speaks • Francis Moore Lappe to Visit Ursinus on February 19th • Ursinus Swimmers Look Towards Champions Meet • Men\u27s Basketball Dominate Centennial Conference • Track Handling Business Indoors • Women\u27s Basketball Can\u27t Find the Right Touchhttps://digitalcommons.ursinus.edu/grizzlynews/1529/thumbnail.jp
Compact high-quality CdSe–CdS core–shell nanocrystals with narrow emission linewidths and suppressed blinking
High particle uniformity, high photoluminescence quantum yields, narrow and symmetric emission spectral lineshapes and minimal single-dot emission intermittency (known as blinking) have been recognized as universal requirements for the successful use of colloidal quantum dots in nearly all optical applications. However, synthesizing samples that simultaneously meet all these four criteria has proven challenging. Here, we report the synthesis of such high-quality CdSe–CdS core–shell quantum dots in an optimized process that maintains a slow growth rate of the shell through the use of octanethiol and cadmium oleate as precursors. In contrast with previous observations, single-dot blinking is significantly suppressed with only a relatively thin shell. Furthermore, we demonstrate the elimination of the ensemble luminescence photodarkening that is an intrinsic consequence of quantum dot blinking statistical ageing. Furthermore, the small size and high photoluminescence quantum yields of these novel quantum dots render them superior in vivo imaging agents compared with conventional quantum dots. We anticipate these quantum dots will also result in significant improvement in the performance of quantum dots in other applications such as solid-state lighting and illumination.National Institutes of Health (U.S.) (Grant 5-U54-CA119349)National Institutes of Health (U.S.) (Grant 5R01CA126642)Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies (W911NF-07-D-0004)National Science Foundation (U.S.) (Collaborative Research in Chemistry Program CHE-0714189)National Science Foundation (U.S.) (Award DMR-08-19762)National Science Foundation (U.S.) (Grant CHE-9808061)National Science Foundation (U.S.) (Grant DBI-9729592
Applying the 'no-one worse off' criterion to design Pareto efficient HIV responses in Sudan and Togo
Lateral flow test performance in children for SARS-CoV-2 using anterior nasal and buccal swabbing: sensitivity, specificity, negative and positive predictive values
ObjectiveTo determine if the sensitivity of the lateral flow test is dependent on the viral load and on the location of swabbing in the respiratory tract in children.DesignPhase 1: Routinely performed reverse transcriptase PCR (RT-PCR) using nose and throat (NT) swabs or endotracheal (ET) aspirates were compared with Innova lateral flow tests (LFTs) using anterior nasal (AN) swabs. Phase 2: RT-PCR-positive children underwent paired AN RT-PCR and LFT and/or paired AN RT-PCR and buccal LFT.SettingTertiary paediatric hospitals.PatientsChildren under the age of 18 years. Phase 1: undergoing routine testing, phase 2: known SARS-CoV-2 positive.ResultsPhase 1: 435 paired swabs taken in 431 asymptomatic patients resulted in 8 positive RT-PCRs, 9 PCR test failures and 418 negative RT-PCRs from NT or ET swabs. The test performance of AN LFT demonstrated sensitivity: 25% (4%-59%), specificity: 100% (99%-100%), positive predictive value (PPV): 100% (18%-100%) and negative predictive value (NPV): 99% (97%-99%).Phase 2: 14 AN RT-PCR-positive results demonstrated a sensitivity of 77% (50%-92%) of LFTs performed on AN swabs. 15/16 paired buccal LFT swabs were negative.ConclusionThe NPV, PPV and specificity of LFTs are excellent. The sensitivity of LFTs compared with RT-PCR is good when the samples are colocated but may be reduced when the LFT swab is taken from the AN. Buccal swabs are not appropriate for LFT testing. Careful consideration of the swabbing reason, the tolerance of the child and the requirements for test processing (eg, rapidity of results) should be undertaken within hospital settings.Trial registration numberNCT04629157
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