1,566 research outputs found
High colloidal stability of gold nanorods coated with a peptide-ethylene glycol: Analysis by cyanide-mediated etching and nanoparticle tracking analysis
The stability of gold nanorods was assessed following coating with various charged or uncharged ligands, mostly peptides. Highly stable monodispersed gold nanorods were obtained by coating CTAB-stabilized gold nanorods with a pentapeptide with C-terminal ethylene glycol units (peptide-EG). UV-vis spectroscopy of these nanorods suspended in saline solutions indicated no signs of aggregation, and they were easily purified using size-exclusion chromatography. A more stringent measure of nanorod stability involved observing changes in the UV-vis absorbance of gold nanorods subjected to etching with cyanide. The max absorbance of peptide-EG coated nanorods red-shifted in etchant solution. The hypothesis that changes in the nanorod aspect ratio led to this red-shift was confirmed by TEM analysis, which showed pit formation along the transverse axis. The etching process was followed in solution using nanoparticle tracking analysis. The red-shift was shown to occur while the particles remained mono-dispersed, and so was not due to aggregation. Adding both etchant solution and peptide-EG to the nanorods was further shown to allow modulation of the max red-shift and increase the etchant resistance of peptide-EG nanorods. Thus, very stable gold nanorods can be produced using the peptide-EG coating approach and their optical properties modulated with etchant
A systematic review of randomised controlled trials of interventions promoting effective condom use
BACKGROUND: Effective condom use can prevent sexually transmitted infections (STIs) and unwanted pregnancy. We conducted a systematic review and methodological appraisal of randomised controlled trials (RCTs) of interventions to promote effective condom use. METHODS: We searched for all RCTs of interventions to promote effective condom use using the Cochrane Infectious Diseases Group's trials register (Oct 2006), CENTRAL (Issue 4, 2006), MEDLINE (1966 to Oct 2006), EMBASE (1974 to Oct 2006), LILACS (1982 to Oct 2006), IBSS (1951 to Oct 2006) and Psychinfo (1996 to Oct 2006). We extracted data on allocation sequence, allocation concealment, blinding, loss to follow-up and measures of effect. Effect estimates were calculated. RESULTS: We identified 139 trials. Seven out of ten trials reported reductions in 'any STI' with five statistically significant results. Three out of four trials reported reductions in pregnancy, although none was statistically significant. Only four trials met all the quality criteria. Trials reported a median of 11 (IQR 7-17) outcome measures. Few trials used the same outcome measure. Altogether, 10 trials (7%) used the outcome 'any STI', 4 (3%) self-reported pregnancy and 22 (16%) used 'condom use at last sex'. CONCLUSIONS: The results are generally consistent with modest benefits but there is considerable potential for bias due to poor trial quality. Because of the low proportion of trials using the same outcome the potential for bias from selective reporting of outcomes is considerable. Despite the public health importance of increasing condom use there is little reliable evidence on the effectiveness of condom promotion interventions
UTILIZING STUDENT ORGANIZATONS AT HISTORICALLY BLACK COLLEGES AND UNIVERSITIES IN THE RURAL SOUTH TO FACILITATE HIV/AIDS EDUCATION
AbstractHIV/AIDS among students at Historically Black Colleges and Universities (HBCU) in the rural South is a growing public health concern. Lack of basic HIV/AIDS knowledge, underestimating risky behaviors, and lack of discussions relating to sexuality are some factors that contribute to the spread of HIV/AIDS within the HBCU population. Objectives of the study included the following: 1) To examine how the issue of HIV/AIDS is viewed by student leaders and organizations on campus; 2) To examine what student organizations and administrators are doing to educate the student body on HIV/AIDS; 3) To identify barriers that student organizations and administrators face when providing education to students; and 4) To examine how student leaders rate their leadership influence when interacting with their peers.This study utilized a qualitative research design in which student leaders and administrators were interviewed and asked a series of questions related to HIV/AIDS education on their campus. Student leader participants were recruited from a university site located in the rural South. Interviews were collected through a 30 minute tape-recorded session on campus. Interview data were analyzed using principles of grounded theory. The findings of the study suggest that student organizations could be a useful vehicle for HIV/AIDS peer-led interventions if their members are well trained and first address underlying issues such as cultural homophobia, sexuality, and stigma relating to HIV/AIDS. Administrators of the university should encourage students to be creative when addressing their peers about issues surrounding HIV/AIDS. Researchers and public health officials must create appropriate interventions to address issues surrounding HIV/AIDS before effective education of HIV/AIDS can take place. Public health significance: Improving HIV education among HBCU students presents a potentially effective strategy that addresses the larger issue of HIV/AIDS among African Americans by focusing their efforts and targeting a smaller sub-population first. The public health relevance of improving education among HBCU campuses is evident when considered in light of this promising possibility. This sub-population is particularly important because many of these individuals will become leaders of the African American community, and influence community behavior and attitudes towards HIV/AIDS
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Can Internet-Based Sexual Health Services Increase Diagnoses of Sexually Transmitted Infections (STI)? Protocol for a Randomized Evaluation of an Internet-Based STI Testing and Results Service.
BACKGROUND: Ensuring rapid access to high quality sexual health services is a key public health objective, both in the United Kingdom and internationally. Internet-based testing services for sexually transmitted infections (STIs) are considered to be a promising way to achieve this goal. This study will evaluate a nascent online STI testing and results service in South East London, delivered alongside standard face-to-face STI testing services. OBJECTIVE: The aim of this study is to establish whether an online testing and results services can (1) increase diagnoses of STIs and (2) increase uptake of STI testing, when delivered alongside standard face-to-face STI testing services. METHODS: This is a single-blind randomized controlled trial. We will recruit 3000 participants who meet the following eligibility criteria: 16-30 years of age, resident in the London boroughs of Lambeth and Southwark, having at least one sexual partner in the last 12 months, having access to the Internet and willing to take an STI test. People unable to provide informed consent and unable to read and understand English (the websites will be in English) will be excluded. Baseline data will be collected at enrolment. This includes participant contact details, demographic data (date of birth, gender, ethnicity, and sexual orientation), and sexual health behaviors (last STI test, service used at last STI test and number of sexual partners in the last 12 months). Once enrolled, participants will be randomly allocated either (1) to an online STI testing and results service (Sexual Health 24) offering postal self-administered STI kits for chlamydia, gonorrhoea, syphilis, and HIV; results via text message (short message service, SMS), except positive results for HIV, which will be delivered by phone; and direct referrals to local clinics for treatment or (2) to a conventional sexual health information website with signposting to local clinic-based sexual health services. Participants will be free to use any other interventions or services during the trial period. At 6 weeks from randomization we will collect self-reported follow-up data on service use, STI tests and results, treatment prescribed, and acceptability of STI testing services. We will also collect objective data from participating STI testing services on uptake of STI testing, STI diagnoses and treatment. We hypothesise that uptake of STI testing and STI diagnoses will be higher in the intervention arm. Our hypothesis is based on the assumption that the intervention is less time-consuming, more convenient, more private, and incur less stigma and embarrassment than face-to-face STI testing pathways. The primary outcome measure is diagnosis of any STI at 6 weeks from randomization and our co-primary outcome is completion of any STI test at 6 weeks from randomization. We define completion of a test, as samples returned, processed, and results delivered to the intervention and/or clinic settings. We will use risk ratios to calculate the effect of the intervention on our primary outcomes with 95% confidence intervals. All analyses will be based on the intention-to-treat (ITT) principle. RESULTS: This study is funded by Guy's and St Thomas' Charity and it has received ethical approval from NRES Committee London-Camberwell St Giles (Ref 14/LO/1477). Research and Development approval has been obtained from Kings College Hospital NHS Foundation Trust and Guy's and St Thomas' NHS Foundation Trust. Results are expected in June 2016. CONCLUSIONS: This study will provide evidence on the effectiveness of an online STI testing and results service in South East London. Our findings may also be generalizable to similar populations in the United Kingdom. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 13354298; http://www.isrctn.com/ISRCTN13354298 (Archived by WebCite at http://www.webcitation.org/6d9xT2bPj)
Inter- and intra-annual bacterioplankton community patterns in a deepwater sub-Arctic region:Persistent high background abundance of putative oil degraders
Oil spills at sea are one of the most disastrous anthropogenic pollution events, with the Deepwater Horizon spill providing a testament to how profoundly the health of marine ecosystems and the livelihood of its coastal inhabitants can be severely impacted by spilled oil. The fate of oil in the environment is largely dictated by the presence and activities of natural communities of oil-degrading bacteria
Deriving nutrient criteria to support 'good' ecological status in European lakes: An empirically based approach to linking ecology and management
European water policy has identified eutrophication as a priority issue for water management. Substantial progress has been made in combating eutrophication but open issues remain, including setting reliable and meaningful nutrient criteria supporting ʽgoodʼ ecological status of the Water Framework Directive. The paper introduces a novel methodological approach - a set of four different methods - that can be applied to different ecosystems and stressors to derive empirically-based management targets. The methods include Ranged Major Axis (RMA) regression, multivariate Ordinary Least Squares (OLS) regression, logistic regression, and minimising the mismatch of classifications. We apply these approaches to establish nutrient (nitrogen and phosphorus) criteria for the major productive shallow lake types of Europe: high alkalinity shallow (LCB1; mean depth 3–15 m) and very shallow (LCB2; mean depth
An analysis of the factors involved in the formation of a cluster of honeybees
It has been found that the stimuli of scent, vibration, and heat, which are produced by a cluster of bees, can each, provided they are of sufficient magnitude, attract individual bees to join it. 2. Bees can be attracted by sight alone towards actively moving bees. 3. Hungry bees prefer to join a cluster of bees from whom they can obtain food; and well-fed bees are more attractive to individual bees than are hungry bees, even when the individual bees are unable to obtain food from well-fed ones
Collaborative Database to Track Mass Mortality Events in the Mediterranean Sea
Postdoctoral contract Juan de la Cierva [IJCI-2016-29329]Ministerio de Ciencia, Innovacion y Universidades PTA2015-10829-IInterreg Med Programme MPA-Adapt 1MED15_3.2_M2_337European Regional Development Fund - Foundation Albert II MonacoEuropean Union’s Horizon 2020Ministry of Education, Spain FPU15/0545
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