bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tailored combination prevention packages and PrEP for young key populations
Authors: Pettifor Audrey , Nguyen Nadia L , Celum Connie , Cowan Frances M , Go Vivian , Hightow‐Weidman Lisa 
Published: February 2015

IntroductionYoung key populations, defined in this article as men who have sex with men, transgender persons, people who sell sex and people who inject drugs, are at particularly high risk for HIV. Due to the often marginalized and sometimes criminalized status of young people who identify as members of key populations, there is a need for HIV prevention packages that account for the unique and challenging circumstances they face. Pre‐exposure prophylaxis (PrEP) is likely to become an important element of combination prevention for many young key populations.ObjectiveIn this paper, we discuss important challenges to HIV prevention among young key populations, identify key components of a tailored combination prevention package for this population and examine the role of PrEP in these prevention packages.MethodsWe conducted a comprehensive review of the evidence to date on prevention strategies, challenges to prevention and combination prevention packages for young key populations. We focused specifically on the role of PrEP in these prevention packages and on young people under the age of 24, and 18 in particular.Results and discussionCombination prevention packages that include effective, acceptable and scalable behavioural, structural and biologic interventions are needed for all key populations to prevent new HIV infections. Interventions in these packages should meaningfully involve beneficiaries in the design and implementation of the intervention, and take into account the context in which the intervention is being delivered to thoughtfully address issues of stigma and discrimination. These interventions will likely be most effective if implemented in conjunction with strategies to facilitate an enabling environment, including increasing access to HIV testing and health services for PrEP and other prevention strategies, decriminalizing key populations’ practices, increasing access to prevention and care, reducing stigma and discrimination, and fostering community empowerment. PrEP could offer a highly effective, time‐limited primary prevention for young key populations if it is implemented in combination with other programs to increase access to health services and encourage the reliable use of PrEP while at risk of HIV exposure.ConclusionsReductions in HIV incidence will only be achieved through the implementation of combinations of interventions that include biomedical and behavioural interventions, as well as components that address social, economic and other structural factors that influence HIV prevention and transmission.
Providing comprehensive health services for young key populations: needs, barriers and gaps
Authors: Delany‐Moretlwe Sinead , Cowan Frances M , Busza Joanna , Bolton‐Moore Carolyn , Kelley Karen , Fairlie Lee 
Published: February 2015

IntroductionAdolescence is a time of physical, emotional and social transitions that have implications for health. In addition to being at high risk for HIV, young key populations (YKP) may experience other health problems attributable to high‐risk behaviour or their developmental stage, or a combination of both.DiscussionWe reviewed the needs, barriers and gaps for other non‐HIV health services for YKP. We searched PubMed and Google Scholar for articles that provided specific age‐related data on sexual and reproductive health; mental health; violence; and substance use problems for adolescent, youth or young sex workers, men who have sex with men, transgender people, and people who inject drugs.ResultsYKP experience more unprotected sex, sexually transmitted infections including HIV, unintended pregnancy, violence, mental health disorders and substance use compared to older members of key populations and youth among the general population. YKP experience significant barriers to accessing care; coverage of services is low, largely because of stigma and discrimination experienced at both the health system and policy levels.DiscussionYKP require comprehensive, integrated services that respond to their specific developmental needs, including health, educational and social services within the context of a human rights‐based approach. The recent WHO Consolidated Guidelines on HIV Prevention, Diagnosis, Treatment and Care for Key Populations are an important first step for a more comprehensive approach to HIV programming for YKP, but there are limited data on the effective delivery of combined interventions for YKP. Significant investments in research and implementation will be required to ensure adequate provision and coverage of services for YKP. In addition, greater commitments to harm reduction and rights‐based approaches are needed to address structural barriers to access to care.
Osteopathic Medical Students' Understanding of the Patient Protection and Affordable Care Act: A First Step Toward a Policy-Informed Curriculum
Authors: Beverly Elizabeth Ann , Skinner Daniel , Bianco Joseph A. , Ice Gillian H. 
Published: February 2015

AbstractContext:Current osteopathic medical students will play an important role in implementing, modifying, and advocating for or against the Patient Protection and Affordable Care Act (ACA) of 2010. Accordingly, medical educators will need to address curricular gaps specific to the ACA and medical practice. Research that gauges osteopathic medical students' level of understanding of the ACA is needed to inform an evidence-based curriculum.Objective:To assess first- and second-year osteopathic medical students' beliefs about the ACA.Methods:In this descriptive cross-sectional survey-based study, first- and second-year students were recruited because their responses would be indicative of what, if any, information about the ACA was being covered in the preclinical curriculum. A 30-item survey was distributed in November 2013, after the health insurance exchanges launched on October 1, 2013.Results:A total of 239 first- and second-year osteopathic medical students completed the survey. One hundred ten students (46%) disagreed and 103 (43.1%) agreed that the ACA would provide health insurance coverage for all US citizens. The ACA was predicted to lead to lower wages and fewer jobs (73 students [30.5%]), as well as small business bankruptcy because of employees' health insurance costs (96 [40.2%]). Regarding Medicare recipients, 113 students (47.3%) did not know whether these individuals would be required to buy insurance through the health insurance exchanges. The majority of students knew that the ACA would require US citizens to pay a penalty if they did not have health insurance (198 [82.8%]) and understood that not everyone would be required to purchase health insurance through health insurance exchanges (137 [57.3%]). Although students took note of certain clinical benefits for patients offered by the ACA, they remained concerned about the ACA's impact on their professional prospects, particularly in the area of primary care.Conclusion:These findings build on the existing literature that emphasize the need for incorporating into the osteopathic medical curriculum knowledge of the dynamics of health care policy and reform and for creating opportunities for students to follow health policy developments as they evolve in real time.
Reliability and Precision of Stress Sonography of the Ulnar Collateral Ligament
Authors: Bica David , Armen Joseph , Kulas Anthony S. , Youngs Kevin , Womack Zachary 
Published: February 2015

ObjectivesMusculoskeletal sonography has emerged as an additional diagnostic tool that can be used to assess medial elbow pain and laxity in overhead throwers. It provides a dynamic, rapid, and noninvasive modality in the evaluation of ligamentous structural integrity. Many studies have demonstrated the utility of dynamic sonography for medial elbow and ulnar collateral ligament (UCL) integrity. However, evaluating the reliabilityand precision of these measurements is critical if sonography is ultimately used as a clinical diagnostic tool. The purpose of this study was to evaluate the reliability and precision of stress sonography applied to the medial elbow.MethodsWe conducted a cross‐sectional study during the 2011 baseball off‐season. Eighteen National Collegiate Athletic Association Division I pitchers were enrolled, and 36 elbows were studied. Using sonography, the medial elbow was assessed, and measurements of the UCL length and ulnohumeral joint gapping were performed twice under two conditions (unloaded and loaded) and bilaterally.ResultsIntraclass correlation coefficients (0.72–0.94) and standard errors of measurements (0.3–0.9 mm) for UCL length and ulnohumeral joint gapping were good to excellent. Mean differences between unloaded and loaded conditions for the dominant arms were 1.3 mm (gapping; P < .001) and 1.4 mm (UCL length; P < .001).ConclusionsMedial elbow stress sonography is a reliable and precise method for detecting changes in ulnohumeral joint gapping and UCL lengthening. Ultimately, this method may provide clinicians valuable information regarding the medial elbow's response to valgus loading and may help guide treatment options.
Noninvasive Evaluation of Liver Fibrosis Using Real‐time Tissue Elastography and Transient Elastography (FibroScan)
Authors: Meng Fankun , Zheng Ying , Zhang Qi , Mu Xiaojie , Xu Xiaoluan , Zhang Haiying , Ding Lei 
Published: February 2015

ObjectivesThe purpose of this study was to assess liver fibrosis with real‐time tissue elastography and to compare the results with those of transient elastographic (FibroScan; Echosens, Paris, France) measurements by using liver biopsy as the reference standard.MethodsReal‐time tissue elastography and percutaneous liver biopsy were performed in 166 patients with chronic hepatitis B (estimation group). The relationship between the parameters obtained via real‐time tissue elastography and the hepatic fibrosis stage was evaluated by a stepwise multiple linear regression, and the regression equation was used to calculate the liver fibrosis index. The diagnostic performance of the liver fibrosis index was validated and compared with FibroScan in 121 other patients with chronic hepatitis B (validation group).ResultsThe liver fibrosis index was calculated as follows: liver fibrosis index = 0.043 low‐strain area ratio + 4.520 skewness + 0.033 mean – 1.002 kurtosis. The liver fibrosis index and liver stiffness measured by FibroScan were both significantly associated with the fibrosis stage in the validation group (r= 0.667 and 0.664, respectively; both P< .001). The areas under the receiver operating characteristic curves for the liver fibrosis index and liver stiffness were 0.880 and 0.909 for predicting substantial fibrosis (scores ≥F2), 0.868 and 0.874 for predicting severe fibrosis (≥F3), and 0.752 and 0.815 for predicting cirrhosis (F4), respectively.ConclusionsReal‐time tissue elastography is an effective method for assessing liver fibrosis, with diagnostic performance similar to that of transient elastography.
External Ultrasound for Carotid Atherosclerotic Plaque Treatment
Authors: Zhang Yan , Dong Honglin , Xu Yuming , Shi Runhua , Gu Jingming , Lang Hongzhi , Gao Jianbo , Zhang Wayne W. 
Published: February 2015

ObjectivesThe purpose of this study was to evaluate the efficacy of external ultrasound in the treatment of carotid atherosclerotic plaques.MethodsIn the prospective study, 357 patients with 363 carotid atherosclerotic plaques were divided into an ultrasound treatment group and a control group. For 30 days, conventional medical treatment was conducted on 54 plaques in the control group, whereas irradiation therapy in addition to conventional medical treatment was conducted on 309 plaques in the ultrasound group. Carotid sonography was conducted before and after treatment, and the maximum plaque thickness and area were measured in a longitudinal section.ResultsNo patients withdrew from the treatment because of related side effects. After treatment, the maximum thickness and area of 79.94% of the plaques in the ultrasound group were reduced, whereas in the control group, the thickness and area of 18.52% were reduced. The mean changes in plaque thickness and area ± SD in the ultrasound and control groups were 0.22 ± 0.19 mm (7.61% ± 5.67%) versus 0.02 ± 0.05 mm (0.74% ± 1.64%) and 0.047 ± 0.039 cm2 (13.28% ± 9.8%) versus 0.0044 ± 0.0102 cm2 (1.1% ± 2.46%), respectively. Changes in both plaque thickness and area in the ultrasound group were significantly greater than those in the control group (P< .0001). Furthermore, the plaque echo type was another prognostic factor affecting efficacy (P < .05).ConclusionsExternal ultrasound treatment is safe and effective for carotid atherosclerotic plaques and is worthy of further research and applications. The efficacy in anechoic/hypoechoic plaques is significantly higher than that in mixed echoic and calcified echoic plaques.
Association of Common Carotid Artery Doppler‐Determined Dicrotic Notch Velocity With the Left Ventricular Ejection Fraction
Authors: Polak Joseph F. , Alessi-Chinetti Jean M. , Patel Ayan R. , Estes James M. 
Published: February 2015

ObjectivesThe appearance of the dicrotic notch on blood pressure tracings is associated with impaired cardiac function. Common carotid artery waveforms have similar fiduciary markers, yet they have not been related to cardiac function. We studied associations of common carotid artery dicrotic notch velocities with the left ventricular ejection fraction (LVEF) determined by echocardiography.MethodsWe conducted a retrospective study of 37 patients who had cardiac echocardiography and carotid Doppler evaluations within 1 day of each other. The LVEF was determined by the biplane modified Simpson rule. Doppler parameters were measured from tracings of the left common carotid artery 4 cm from the flow divider. Linear regression and stepwise multivariable linear regression models were used to evaluate any association between the LVEF and the following variables: age, sex, peak systolic velocity (PSV), end‐diastolic velocity (EDV), dicrotic notch velocity, rise time (EDV to PSV), resistive index, and cardiac cycle length.ResultsThe dicrotic notch velocity was the only variable associated with the LVEF (P = .028) in a bivariate analyses. A backward selection stepwise multivariable equation predicting the LVEF had the dicrotic notch (P = .001) and resistive index (P = .01) as significant predictors, whereas the cardiac cycle length (P = .08) and PSV (P = .08) were borderline not significant. Model goodness of fit was R2 = 0.37 (P = .004).ConclusionsDicrotic notch velocities measured from common carotid artery Doppler waveforms are associated with the LVEF and might offer some clinical value in selected cases.
Characterization of Coronary Flow Reserve and Left Ventricular Remodeling in a Mouse Model of Chronic Aortic Regurgitation With Carvedilol Intervention
Authors: Wang Xiangfei , Wu Jian , Zhu Dan , You Jieyun , Zou Yunzeng , Qian Juying , Ge Junbo 
Published: February 2015

ObjectivesWe hypothesized that left ventricular (LV) remodeling might be exaggerated by an impaired coronary flow reserve in mice with chronic severe aortic regurgitation, and carvedilol, a β‐adrenoceptor blocker, could regress the course.MethodsSevere aortic regurgitation was induced by retrograde puncture of the aortic valve leaflets under sonographic guidance in 12‐week‐old male C57BL/6J mice. Four weeks after regurgitation, the mice were treated with carvedilol (30 mg/kg/d) or not treated (control). Before and 4 weeks after carvedilol treatment, the coronary flow reserve and LV structure and function were evaluated by echocardiography. Cardiomyocytes and fibrosis were validated by histologic analysis.ResultsFour‐week aortic regurgitation caused a decreased LV ejection fraction and an increased LV end‐systolic volume index. Regurgitation also impaired the coronary flow reserve due to an increase in the basal coronary peak diastolic velocity and velocity‐time integral combined with the absence of substantial changes in the hyperemic coronary peak diastolic velocity and velocity‐time integral. Four more weeks of regurgitation further deteriorated LV remodeling and coronary perfusion in the control group. In contrast, the carvedilol‐treated group showed attenuated LV remodeling and a higher coronary flow reserve by decreasing the basal peak diastolic velocity and velocity‐time integral without substantial changes in the hyperemic peak diastolic velocity and velocity‐time integral. The coronary flow reserve and its pretreatment versus posttreatment difference were positively correlated with the pretreatment versus posttreatment LV ejection fraction and end‐systolic volume index differences. In the carvedilol‐treated group, subendocardial fibrosis was significantly reduced (P < .05), and the cardiomyocyte cross‐sectional area tended to be smaller.Conclusions—In mice with chronic severe aortic regurgitation, carvedilol therapy significantly improves the impaired coronary flow reserve and sufficiently attenuates adverse LV remodeling. Sustained coronary flow reserve impairment indicates progressive LV remodeling.
Microtopographic and depth controls on active layer chemistry in Arctic polygonal ground
Authors: Newman B. D. , Throckmorton H. M. , Graham D. E. , Gu B. , Hubbard S. S. , Liang L. , Wu Y. , Heikoop J. M. , Herndon E. M. , Phelps T. J. , Wilson C. J. , Wullschleger S. D. 
Published: February 2015

AbstractPolygonal ground is a signature characteristic of Arctic lowlands, and carbon release from permafrost thaw can alter feedbacks to Arctic ecosystems and climate. This study describes the first comprehensive spatial examination of active layer biogeochemistry that extends across high‐ and low‐centered, ice wedge polygons, their features, and with depth. Water chemistry measurements of 54 analytes were made on surface and active layer pore waters collected near Barrow, Alaska, USA. Significant differences were observed between high‐ and low‐centered polygons suggesting that polygon types may be useful for landscape‐scale geochemical classification. However, differences were found for polygon features (centers and troughs) for analytes that were not significant for polygon type, suggesting that finer‐scale features affect biogeochemistry differently from polygon types. Depth variations were also significant, demonstrating important multidimensional aspects of polygonal ground biogeochemistry. These results have major implications for understanding how polygonal ground ecosystems function, and how they may respond to future change.
Turbulent nitrate fluxes in the Lower St. Lawrence Estuary, Canada
Authors: Cyr Frédéric , Bourgault Daniel , Galbraith Peter S. , Gosselin Michel 
Published: February 2015

AbstractTurbulent vertical nitrate fluxes were calculated using new turbulent microstructure observations in the Lower St. Lawrence Estuary (LSLE), Canada. Two stations were compared: the head of the Laurentian Channel (HLC), where intense mixing occurs on the shallow sill that marks the upstream limit of the LSLE, and another station located about 100 km downstream (St. 23), more representative of the LSLE mean mixing conditions. Mean turbulent diffusivities and nitrate fluxes at the base of the surface layer for both stations were, respectively (with 95% confidence intervals):
and
. Observations suggest that the interplay between large isopleth heaving near the sill and strong turbulence is the key mechanism to sustain such high turbulent nitrate fluxes at the HLC (two to three orders of magnitude higher than those at Station 23). Calculations also suggest that nitrate fluxes at the HLC alone can sustain primary production rates of
over the whole LSLE, approximately enough to account for a large part of the phytoplankton bloom and for most of the postbloom production. Surfacing nitrates are also believed to be consumed within the LSLE, not leaving much to be exported to the rest of the Gulf of St. Lawrence.
RACORO continental boundary layer cloud investigations: 3. Separation of parameterization biases single‐column model CAM5 simulations of shallow cumulus
Authors: Lin Wuyin , Liu Yangang , Vogelmann Andrew M. , Fridlind Ann , Endo Satoshi , Song Hua , Feng Sha , Toto Tami , Li Zhijin , Zhang Minghua 
Published: February 2015

AbstractClimatically important low‐level clouds are commonly misrepresented in climate models. The FAst‐physics System TEstbed and Research (FASTER) Project has constructed case studies from the Atmospheric Radiation Measurement Climate Research Facility's Southern Great Plain site during the RACORO aircraft campaign to facilitate research on model representation of boundary‐layer clouds. This paper focuses on using the single‐column Community Atmosphere Model version 5 (SCAM5) simulations of a multi‐day continental shallow cumulus case to identify specific parameterization causes of low‐cloud biases. Consistent model biases among the simulations driven by a set of alternative forcings suggest that uncertainty in the forcing plays only a relatively minor role. In‐depth analysis reveals that the model's shallow cumulus convection scheme tends to significantly under‐produce clouds during the times when shallow cumuli exist in the observations, while the deep convective and stratiform cloud schemes significantly over‐produce low‐level clouds throughout the day. The links between model biases and the underlying assumptions of the shallow cumulus scheme are further diagnosed with the aid of large‐eddy simulations and aircraft measurements, and by suppressing the triggering of the deep convection scheme. It is found that the weak boundary layer turbulence simulated is directly responsible for the weak cumulus activity and the simulated boundary layer stratiform clouds. Increased vertical and temporal resolutions are shown to lead to stronger boundary layer turbulence and reduction of low‐cloud biases.