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We use quantum trajectory theory to study the dynamics of the first step in photosynthesis for a single photon interacting with photosystem II (PSII). By considering individual trajectories we are able to look beyond the ensemble average dynamics to compute the PSII system evolution conditioned upon individual photon counting measurements. Measurements of the transmitted photon beam strongly affects the system state, since detection of an outgoing photon confirms that the PSII must be in the electronic ground state, while a null measurement implies it is in an excited electronic state. We show that under ideal conditions, observing the null result transforms a state with a low excited state population to a state with nearly all population contained in the excited states. We study the PSII dynamics conditioned on such photon counting for both a pure excitonic model of PSII and a more realistic model with exciton-phonon coupling to a dissipative phononic environment. In the absence of such coupling, we show that the measured fluorescence rates show oscillations constituting a photon-counting witness of excitonic coherence. Excitonic coupling to the phonon environment has a strong effect on the observed rates of fluorescence, damping the oscillations. Addition of non-radiative decay and incoherent transitions to radical pair states in the reaction center to the phononic model allows extraction of a quantum efficiency of 92.5% from the long-time evolution, consistent with bulk experimental measurements. [ABSTRACT FROM AUTHOR]

We develop a method to simulate the excitonic dynamics of realistic photosynthetic light harvesting systems, including non-Markovian coupling to phonon degrees of freedom, under excitation by N-photon Fock state pulses. This method combines the input–output and the hierarchical equations of motion formalisms into a double hierarchy of density matrix equations. We show analytically that under weak field excitation relevant to natural photosynthesis conditions, an N-photon Fock state input and a corresponding coherent state input give rise to equal density matrices in the excited manifold. However, an N-photon Fock state input induces no off-diagonal coherence between the ground and excited subspaces, in contrast with the coherences created by a coherent state input. We derive expressions for the probability to absorb a single Fock state photon with or without the influence of phonons. For short pulses (or, equivalently, wide bandwidth pulses), we show that the absorption probability has a universal behavior that depends only upon a system-dependent effective energy spread parameter Δ and an exciton–light coupling constant Γ. This holds for a broad range of chromophore systems and for a variety of pulse shapes. We also analyze the absorption probability in the opposite long pulse (narrow bandwidth) regime. We then derive an expression for the long time emission rate in the presence of phonons and use it to study the difference between collective vs independent emission. Finally, we present a numerical simulation for the LHCII monomer (14-mer) system under single photon excitation that illustrates the use of the double hierarchy equations. [ABSTRACT FROM AUTHOR]

Objective: PLWH report using cannabis for both recreational reasons and HIV symptom management (e.g., nausea, pain, depression/anxiety). Recent literature suggests that cannabis may attenuate HIV symptoms and neuroinflammation, which are strongly related to neurocognition. Additionally, older adults who are particularly vulnerable to cognitive impairment experience a decline in the endogenous cannabinoid system with age. Therefore, the aims of the present study were 1) to determine if cannabis use is associated with cognitive performance in PLWH, 2) to determine if age moderates the relationship between cannabis use and cognition in PLWH, and 3) to determine if there are differences in cognition in cannabis non-users, occasional users, and daily users among PLWH. Participants and Methods: The sample included 225 PLWH (78% undetectable; 51% female, Mean age=49.10) who were classified as non-users (n=52), occasional users (n=53), or daily users (n=120). Cannabis use was measured via the Timeline Follow-back (TLFB). Cognition was examined using the NIH Toolbox Cognition Battery, which included measures of attention, working memory, executive function, processing speed, and episodic memory, as well as a fluid cognition composite score. Results: Increased frequency of cannabis use was weakly positively associated with episodic memory performance, r(224) = 0.15, p<0.05. Results of the multiple regression indicate that frequency of cannabis use was not significantly associated with any of the six cognitive domains. However, there was a significant interaction between age and cannabis use in the domains of attention (ß= 0.13, p < 0.05), working memory (ß= 0.12, p < 0.05), and episodic memory (ß= 0.15, p < 0.05), suggesting worse cognitive performance in older adults who use cannabis as compared to younger adults in this sample. When participants were grouped based on use status, there were no significant main effects of group. Conclusions: After controlling for the effects of demographic factors and HIV disease severity, no significant negative associations between cannabis use and cognition were observed, suggesting that cannabis use is not related to cognitive impairment in PLWH. However, results were clarified by a significant interaction, indicating that older adults who use cannabis perform worse in the domains of attention, working memory, and episodic memory compared to younger adults, suggesting synergistic cognitive effects of age and cannabis use. We additionally found preliminary evidence for a potential positive effect of cannabis use on episodic memory in the overall sample. Future studies examining biological and behavioral mechanisms of improvement will be necessary to better examine this relationship. [ABSTRACT FROM AUTHOR]

Studies of viral suppression on first-line antiretroviral therapy (ART) in persons living with human immunodeficiency virus (PLHIV) in Haiti are limited, particularly among PLHIV outside of the Ouest department, where the capital Port-au-Prince is located. This study described the prevalence and risk factors for delayed viral suppression among PLHIV in all geographic departments of Haiti between 2013 and 2017. Individuals who received viral load testing 3 to 12 months after ART initiation were included. Data on demographics and clinical care were obtained from the Haitian Active Longitudinal Tracking of HIV database. Multivariable logistic regression was performed to predict delayed viral suppression, defined as a viral load ≥1000 HIV-1 RNA copies/mL after at least 3 months on ART. Viral load test results were available for 3,368 PLHIV newly-initiated on ART. Prevalence of delayed viral suppression was 40%, which is slightly higher than previous estimates in Haiti. In the multivariable analysis, delayed viral suppression was significantly associated with younger age, receiving of care in the Ouest department, treatment with lamivudine (3TC), zidovudine (AZT), and nevirapine (NVP) combined ART regimen, and CD4 counts below 200 cells/mm3. In conclusion, this study was the first to describe and compare differences in delayed viral suppression among PLHIV by geographic department in Haiti. We identified populations to whom public health interventions, such as more frequent viral load testing, drug resistance testing, and ART adherence counseling should be targeted. [ABSTRACT FROM AUTHOR]

Background: Alcohol consumption is associated with poor health outcomes in women living with HIV (WLWH), but whether medication can help to reduce drinking in non–treatment‐seeking women or whether reduction in drinking improves HIV outcomes is unclear. We conducted a randomized clinical trial (RCT) of daily oral naltrexone (50 mg) versus placebo in WLWH who met criteria for current unhealthy alcohol use. Methods: WLWH with current unhealthy alcohol use (>7 drinks/wk or >3 drinks/occasion) were randomly assigned to daily oral naltrexone 50 mg (n = 96) or placebo (n = 98) for 4 months. Drinking outcomes, including the proportion of women who reduced (

Background: The relationship between lifetime abuse (i.e., childhood abuse, intimate partner violence) and risky behaviors is well established. One proposed mechanism is poor emotion regulation and executive functioning, as a potential mechanism that may explain the relationship between lifetime abuse and risky behaviors. However, research on executive functioning and emotion regulation as mediators of this relationship has been limited. In the present study, we examined this association. We hypothesized that lifetime abuse would be significantly associated with executive function and emotion regulation which in turn would be associated with greater alcohol use and risky sex. Methods: This cross-sectional study included 150 women with a history of lifetime abuse who were assessed for hazardous alcohol use using the AUDIT Score; emotion regulation was measured using the Difficulties with Emotion Regulation Scale (DERS); risky sex was measured using the question: "in the last 90 days, how many people did you have anal or vaginal sex without using a condom? Executive function was assessed using the NIH Toolbox. Results: The mediation model followed the self-regulation theory, which proposes executive function as the higher-order cognitive process. Results showed that executive function deficit and poor emotion regulation significantly mediated the relationship between lifetime abuse and hazardous alcohol use (indirect effect =.097, SE.031, 95% CI =.035 to.158). Conclusion: Our findings suggest a higher-order cognitive process with executive function promoting emotion regulation as a potential mechanism for alcohol problems in women of color who experienced lifetime abuse. [ABSTRACT FROM AUTHOR]

Background Women living with HIV/AIDS who drink alcohol are at increased risk for adverse health outcomes, but there is little evidence on best methods for reducing alcohol consumption in this population. We conducted a pilot study to determine the acceptability and feasibility of conducting a larger randomized clinical trial of naltrexone vs. placebo to reduce alcohol consumption in women living with HIV/AIDS. Methods We designed the trial with input from community and scientific review. Women with HIV who reported current hazardous drinking (> 7 drinks/week or ≥ 4 drinks per occasion) were randomly assigned to daily oral naltrexone (50 mg) or placebo for 4 months. We evaluated willingness to enroll, adherence to study medication, treatment side effects, and drinking and HIV-related outcomes. Results From 2010 to 2012, 17 women enrolled (mean age 49 years, 94% African American). Study participation was higher among women recruited from an existing HIV cohort study compared to women recruited from an outpatient HIV clinic. Participants took 73% of their study medication; 82% completed the final assessment (7-months). Among all participants, mean alcohol consumption declined substantially from baseline to month 4 (39.2 vs. 12.8 drinks/week, p < 0.01) with continued reduction maintained at 7-months. Drinking reductions were similar in both naltrexone and placebo groups. Conclusions A pharmacologic alcohol intervention was acceptable and feasible in women with HIV, with reduced alcohol consumption noted in women assigned to both treatment and placebo groups. However, several recruitment challenges were identified that should be addressed to enhance recruitment in future alcohol treatment trials. [ABSTRACT FROM AUTHOR]

Background: Marijuana use is common among HIV+ individuals, but few studies have examined long-term trends in prevalence and correlates of use.Methods: We evaluated trends (1984-2013) in the annual prevalence of current (past 6-month use) and daily (among current users) marijuana use and determined correlates of use among 2742 HIV-seropositive (HIV+) and 3172 HIV-seronegative (HIV-) men who have sex with men in the Multicenter AIDS Cohort Study (MACS). Poisson regression models were used to estimate prevalence ratios of marijuana use separately for the men who were enrolled before 2001 (early-cohort) and after 2001 (late-cohort).Results: Over the 29 years of the study, the prevalence of current marijuana use declined significantly, whereas daily use among users increased among all men in the early and late-cohorts. A HIV+ status was associated with higher prevalence of marijuana use among the men in the early-cohort (adjusted prevalence ratio [aPR] = 1.53, 95% confidence interval [CI]:1.42, 1.64, p = <0.0001), but not in the men in the late-cohort (aPR = 0.90, 95% CI: 0.79, 1.03, p = 0.1424). Alcohol use and cigarette smoking were being positively associated with marijuana use.Conclusions: Although the annual prevalence of current marijuana use decreased significantly over time in the MACS, daily use among users increased significantly. Further, among the HIV+ men, our study did not show clinically significant adverse effects of marijuana use on highly active antiretroviral therapy use, CD4+ count, or HIV viral load. [ABSTRACT FROM AUTHOR]

Background: Women living with HIV have increased prevalence of medical and psychological comorbidities that could be adversely affected by alcohol consumption. Little is known about their unique motivations for drinking or perceptions of HIV-related consequences. In preparation for an alcohol intervention study, we sought to better understand reasons for drinking and perceived consequences of alcohol consumption among a sample of women living with HIV.Methods: Four focus groups, with a total of 24 adult women (96% African-American, 88% HIV-positive), were conducted in Jacksonville, FL, Washington, DC and Chicago, IL. Focus group discussions were tape-recorded and transcribed verbatim; a conventional content analysis approach was used to identify themes, that were then grouped according to a biopsychosocial model.Results: Regarding reasons for drinking, women described themes that included biological (addiction, to manage pain), psychological (coping, to escape bad experiences, to feel in control), and social (peer pressure, family). Themes related to consequences from alcohol included biological (damage to body, poor adherence to medications), psychological (risky or regrettable behavior, memory loss), and social (jail, loss of respect, poor choices). When discussing how their drinking impacted their health, women focused on broader issues, rather than HIV-specific issues.Conclusion: Many women living with HIV are drinking alcohol in order to self-manage pain or emotions, and their perceived consequences from drinking extend beyond HIV-specific medical issues. Most participants described themes related to psychological issues and situations that are common in women living with HIV. Interventions to address drinking should inquire more specifically about drinking to manage pain or emotion, and help women to recognize the potential adverse impact of alcohol on comorbid health issues, including their own HIV infection. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) is found in most natural waters at concentrations low enough to make DOM isolation methodologies critical to full analytical characterization and preservation. During the last few decades, two major protocols have been developed for the extraction of DOM isolates from natural waters. These methods utilize XAD resins and reverse osmosis (RO). In this work, the hydrophobic acid (May 2012 HPOA) and transphilic acid (May 2012 TPIA) isolates from XAD-8 and XAD-4 resins, respectively, were compared with the RO (May 2012 RO) natural organic matter isolate of the Suwannee River water using 13C nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopies. 13C NMR analysis showed that the May 2012 RO isolate could be viewed as a hybrid of the more hydrophobic May 2012 HPOA isolate and more hydrophilic May 2012 TPIA isolate. The May 2012 HPOA isolate is shown to be higher in alkyl and aromatic moieties, while the May 2012 TPIA isolate is higher in O-alkyl moieties. EPR analysis revealed that the May 2012 TPIA and, in particular, May 2012 HPOA isolates had higher radical concentrations than the May 2012 RO isolate. It is postulated that some of the radical concentrations came from the use of base during the isolation procedures, especially in the XAD method. [ABSTRACT FROM AUTHOR]

Background: Oral human papillomavirus (HPV) is associated with a rising incidence of certain head and neck cancers, and oral sex has been associated with oral HPV. This study sought to identify more specific patterns of oral sexual activity, including self-inoculation, that are associated with oral HPV infections in young women.Methods: A total of 1010 women attending a large university completed a computer-based questionnaire and provided oral specimens that were tested for any oral HPV using a Linear Array assay that detects any HPV as well as 37 HPV genotypes. Twenty-seven women provided additional samples up to 12 months after enrollment. Bivariable and multivariable analyses were conducted to identify oral sexual patterns and other risk factors associated with prevalent oral HPV.Results: Nineteen women had prevalent oral HPV (1.9%), with 10 women (1%) having a type-specific infection. Oral HPV was significantly associated with lifetime coital sex partnership numbers (P = 0.03), lifetime and yearly oral sex partnership numbers (P < 0.01), and hand and/or sex toy transfer from genitals to mouth (P < 0.001). Oral HPV was also associated with greater use of alcohol, cigarettes, marijuana, and sharing of smoking devices, lipstick, or toothbrushes (P < 0.05 for each), with an apparent dose-response for alcohol use and smoking behavior, stratified by number of sexual partners. Of 7 women with prevalent HPV who provided follow-up samples, none had evidence of a persistent type-specific infection.Conclusions: These data provide additional evidence of transmission of oral HPV from oral sexual activity and also suggest possible transmission from self-inoculation or sharing of oral products. [ABSTRACT FROM AUTHOR]

Background: Transdermal alcohol biosensors measure alcohol use continuously, passively, and non‐invasively. There is little field research on the Skyn biosensor, a new‐generation, wrist‐worn transdermal alcohol biosensor, and little evaluation of its sensitivity and specificity and the day‐level correspondence between transdermal alcohol concentration (TAC) and number of self‐reported drinks. Methods: Participants (N = 36; 61% male, Mage = 34.3) wore the Skyn biosensor and completed ecological momentary assessment (EMA) surveys about their alcohol use over 2 weeks. A total of 497 days of biosensor and EMA data were collected. Skyn‐measured drinking episodes were defined by TAC > 5 μg/L. Skyn data were compared to self‐reported drinking to calculate sensitivity and specificity (for drinking day vs. nondrinking day). Generalized estimating equations models were used to evaluate the correspondence between TAC features (peak TAC and TAC‐area under the curve (AUC)) and number of drinks. Individual‐level factors (sex, age, race/ethnicity, body mass index, human immunodeficiency virus status, and hazardous drinking) were examined to explore associations with TAC controlling for number of drinks. Results: Using a minimum TAC threshold of 5 μg/L plus coder review, the biosensor had sensitivity of 54.7% and specificity of 94.6% for distinguishing drinking from nondrinking days. Without coder review, the sensitivity was 78.1% and the specificity was 55.2%. Peak TAC (β = 0.92, p < 0.0001) and TAC‐AUC (β = 1.60, p < 0.0001) were significantly associated with number of drinks. Females had significantly higher TAC levels than males for the same number of drinks. Conclusions: Skyn‐derived TAC can be used to measure alcohol use under naturalistic drinking conditions, additional research is needed to accurately identify drinking episodes based on Skyn TAC readings. [ABSTRACT FROM AUTHOR]

The interaction of humic acids (HAs) with 1-palmitoyl-2-oleoyl-Sn-glycero-3-phosphocholine (POPC) large unilamellar vesicle (LUV) model biomembrane system was studied by fluorescence spectroscopy. HAs from aquatic and terrestrial (including coal) sources were studied. The effects of HA concentration and temperature over environmentally relevant ranges of 0 to 20 mg C/L and 10 to 30 °C, respectively, were investigated. The dosage studies revealed that the aquatic Suwannee River humic acid (SRHA) causes an increased biomembrane perturbation (percent leakage of the fluorescent dye, Sulforhodamine B) over the entire studied concentration range. The two terrestrial HAs, namely Leonardite humic acid (LAHA) and Florida peat humic acid (FPHA), at concentrations above 5 mg C/L, show a decrease or a plateau effect attributable to the competition within the HA mixture and/or the formation of "partial aggregates". The temperature studies revealed that biomembrane perturbation increases with decreasing temperature for all three HAs. Kinetic studies showed that the membrane perturbation process is complex with both fast and slow absorption (sorption into the bilayer) components and that the slow component could be fitted by first order kinetics. A mechanism based on "lattice errors" within the POPC LUVs is put forward to explain the fast and slow components. A rationale behind the concentration and temperature findings is provided, and the environmental implications are discussed. [ABSTRACT FROM AUTHOR]

The effect of low temperature thermal treatment on soils from a former Superfund wood-treating site contaminated with pentachlorophenol (PCP) and the environmentally persistent free radical (EPFR), pentachlorophenoxyl, was determined. The pentachlorophenoxyl EPFRs' and the PCP molecules' chemical behavior were simultaneously monitored at temperatures ranging from 25 to 300 °C via electron paramagnetic resonance (EPR) spectroscopy and GC-MS analysis, respectively. Two types of thermal treatment were employed: a closed heating (oxygen-starved condition) where the soil was heated under vacuum and an open heating system (oxygen-rich conditions), where the soil was heated in ambient air. EPR analyses for closed heating indicated the EPFR concentration was 2-12 × 1018 spins/g of soil, with a g-factor and line width (ΔHp-p) of 2.00311 - 2.00323 and 4.190 - 5.472 G, respectively. EPR analyses for the open heating soils revealed a slightly broader and weaker radical signal, with a concentration of 1-10 × 1018 spins/g of soil, g-factor of 2.00327 - 2.00341, and ΔHp-p of 5.209-6.721 G. This suggested the open heating resulted in the formation of a more oxygen-centered structure of the pentachlorophenoxyl radical or additional, similar radicals. The EPFR concentration peaked at 10 × 1018 spins/g of soil at 100 °C for open heating and 12 × 1018 spins/g at 75 °C for closed heating. The half-lives of the EPFRs were 2-24 days at room temperature in ambient air. These results suggest low temperature treatment of soils contaminated with PCP can convert the PCP to potentially more toxic pentachlorophenoxyl EPFRs, which may persist in the environment long enough for human exposure. [ABSTRACT FROM AUTHOR]

Abstract: Here we present results of an initial assessment of the impacts of a water diversion event on the concentrations and chemical composition of dissolved organic matter (DOM) and bacterioplankton community composition in Barataria Bay, Louisiana U.S.A, an important estuary within the Mississippi River Delta complex. Concentrations and spectral properties of DOM, as reflected by UV/visible absorbance and fluorescence, were strikingly similar at 26 sites sampled along transects near two western and two eastern areas of Barataria Bay in July and September 2010. In September 2010, dissolved organic carbon (DOC) was significantly higher (568.1–1043 μM C, x = 755.6 +/− 117.7 μM C, n = 14) than in July 2010 (249.1–577.1 μM C, x = 383.7 +/− 98.31 μM C, n = 14); conversely, Abs254 was consistently higher at every site in July (0.105–0.314) than in September (0.080–0.221), averaging 0.24 ± 0.06 in July and 0.15 ± 0.04 in September. Fluorescence data via the fluorescence index (FI450/500) revealed that only 30% (8 of 26) of the July samples had an FI450/500 above 1.36, compared to 96% (25 of 26) for the September samples. This indicates a more terrestrial origin for the July DOM. Bacterioplankton from eastern sites differed in composition from bacterioplankon in western sites in July. These differences appeared to result from reduced salinities caused by the freshwater diversion. Bacterioplankton communities in September differed from those in July, but no spatial structure was observed. Thus, the trends in bacterioplankton and DOM were likely due to changes in water masses (e.g., input of Mississippi River water in July and a return to estuarine waters in September). Discharge of water from the Davis Pond Freshwater Diversion (DPFD) through Barataria Bay may have partially mitigated some adverse effects of the oil spill, inasmuch as DOM is concerned. [Copyright &y& Elsevier]

Abstract: The association between background, enduring environmental exposure to polycyclic aromatic hydrocarbons (PAHs) and cardiovascular diseases has not been well studied in the general population. In this study, we used the National Health and Nutrition Examination Survey (NHANES) 2001–2004 to investigate the associations between eight monohydroxy PAHs (OH-PAHs) and self-report CVD. In a logistic regression model adjusting for cigarette smoking and other covariates, phenanthrene metabolite, 2-hydroxyphennathrene (2-PHEN), was significantly associated with self-report CVD. Compared to subjects within the lowest tertile of 2-PHEN, subjects within the middle and highest tertiles had higher self-report CVD (the 2nd tertile: AOR=1.29, 95%CI: 0.97–1.72; the 3rd tertile: AOR=1.45, 95%CI: 1.01–2.07; p for trend=0.04). In addition, fluorene metabolite (i.e. 2-hydroxyfluorene) also showed a marginally significant linear trend with self-report CVD (p for trend=0.07). Further studies are necessary to explore the associations between these highly prevalent pollutants and CVD. [ABSTRACT FROM AUTHOR]

OBJECTIVES: We used the 2001-2004 National Health and Nutrition Examination Survey to examine the association between postnatal environmental tobacco smoke exposure, measured as serum cotinine levels, and attention-deficit/hyperactivity disorder (ADHD) among children 4 to 15 years of age. We further investigated the interactions of race and serum cotinine levels with ADHD. METHODS: Logistic regression models were used to evaluate associations. RESULTS: This study found that the prevalence of ADHD increased as blood cotinine levels increased. The effects of blood cotinine levels on ADHD differed according to race. Compared with children of the same racial group with the lowest blood cotinine levels, the odds ratios were 2.72 (95% confidence interval: 1.25-5.93) for Mexican American children and 5.32 (95% confidence interval: 1.55-1 8.3) for children in other racial groups with the highest blood cotinine levels, with controlling for the effect of maternal smoking during pregnancy. However, no significant associations between blood cotinine levels and ADHD were observed among non-Hispanic white or non-Hispanic black children. CONCLUSIONS: The findings of this study underscore the possibility of racial disparities in the effects of environmental tobacco smoke on behavioral problems in children. These findings warrant further investigation. [ABSTRACT FROM AUTHOR]

One information technology that may be considered by transportation managers, and which is included in the portfolio of technologies that encompass TMS, is artificial neural networks (ANNs). These artificially intelligent computer decision support software provide solutions by finding and recognizing complex patterns in data. ANNs have been used successfully by transportation managers to forecast transportation demand, estimate future transport costs, schedule vehicles and shipments, route vehicles and classify carriers for selection. Artificial neural networks excel in transportation decision environments that are dynamic, complex and unstructured. This article introduces ANNs to transport managers by describing ANN technological capabilities, reporting the current status of transportation neural network applications, presenting ANN applications that offer significant potential for future development and offering managerial guidelines for ANN development. [ABSTRACT FROM AUTHOR]

Background: Health care providers may be concerned that prescribing erectile dysfunction drugs (EDD) will contribute to risky sexual behavior.Objectives: To identify characteristics of men who received EDD prescriptions, determine whether EDD receipt is associated with risky sexual behavior and sexually transmitted diseases (STDs), and determine whether these relationships vary for certain sub-groups.Design: Cross-sectional study.Participants: Two thousand seven hundred and eighty-seven sexually-active, HIV-infected and HIV-uninfected men recruited from eight Veterans Health Affairs outpatient clinics. Data were obtained from participant surveys, electronic medical records, and administrative pharmacy data.Measures: EDD receipt was defined as two or more prescriptions for an EDD, risky sex as having unprotected sex with a partner of serodiscordant or unknown HIV status, and STDs, according to self-report.Results: Overall, 28% of men received EDD in the previous year. Eleven percent of men reported unprotected sex with a serodiscordant/unknown partner in the past year (HIV-infected 15%, HIV-uninfected 6%, P < 0.001). Compared to men who did not receive EDD, men who received EDD were equally likely to report risky sexual behavior (11% vs. 10%, p = 0.9) and STDs (7% vs 7%, p = 0.7). In multivariate analyses, EDD receipt was not significantly associated with risky sexual behavior or STDs in the entire sample or in subgroups of substance users or men who had sex with men.Conclusion: EDD receipt was common but not associated with risky sexual behavior or STDs in this sample of HIV-infected and uninfected men. However, risky sexual behaviors persist in a minority of HIV-infected men, indicating ongoing need for prevention interventions. [ABSTRACT FROM AUTHOR]

Background: Vaginal microbicides have the potential to reduce HIV/STD acquisition when used consistently. Our objectives were to determine product attributes associated with willingness to use a vaginal microbicide and whether product preferences varied according to participant characteristics. Methods: Women ( n = 408) with bacterial vaginosis (BV) were recruited as part of a randomized trial to prevent BV. Participants completed a survey interview that assessed demographic information, sexual history, and douching behavior. To assess microbicide preferences, women rated whether specific product attributes would make them more or less likely to use a vaginal microbicide. Principal components analyses revealed two major groupings for the product attribute items. We determined the relative importance of each group of product attributes and whether the importance of the different groupings varied among subgroups of women. Results: The participants' mean age was 24 years (range 14–45), 64% were black, and 74% were unmarried. Overall, participants reported being most likely to use a vaginal product with protection properties (2.54), whereas they were nearly neutral regarding side effects (0.56). The individual product attributes, could prevent BV, could prevent vaginal odor (2.72), and could prevent vaginal itching and burning (2.61), were rated similarly or slightly higher than could reduce the risk of getting an STD (2.58) or could reduce the risk of getting HIV (2.44). In multivariate analyses, protection attributes were rated significantly higher among older women and marginally higher in women with a greater number of lifetime sexual partners. Younger women were most likely to report that side effects would affect their likelihood of using the product. Conclusions: Women with BV rated potential protection features of a vaginal microbicide higher than side effects. A product's personal hygiene aspects were rated equally or more important than the product's ability to prevent HIV/STD infections. Younger women may respond to different factors that influence product acceptability and adherence. [ABSTRACT FROM AUTHOR]

The article presents a study on the characteristics of sexual partner and sexually transmitted diseases (STD) among young adults and adolescents. It reveals the assessment of sexual partner characteristics, individual sexual activities, and STD diagnosis of clinic attendees. It cites the use of logistic regression to compute the odd ratios (OR) for sexual partner characteristics, demographic profiles, individual sexual activities, and the use of condom. It found out the association of age and history of STD as the prevailing sexual partner characteristics while composite partner risk is related to STD diagnosis. It further asserts the increased risk of prevalent STD in sexual partner characteristics.

Background: Avian influenza is an emerging threat to public health, but little is known about how the public perceives this threat. The objective of this study was to describe beliefs, attitudes and knowledge regarding avian influenza among patients in an internal medicine clinic. Study design: Cross-sectional survey. Methods: Four hundred adult patients in an internal medicine clinic received the survey between April and June 2006. Results: The most common sources of information about avian influenza were local and national television news (74%), came news (51%) and newspapers (50%). The mean percentage of correct answers to seven questions regarding knowledge of avian influenza was 49%. Multivariable linear regression using the percentage of correct answers to these questions as the primary outcome showed that: (1) cortege education, Internet and cable news as sources; (2) income greater than $75,000; and (3) receiving an influenza vaccine in the last influenza season were positively associated with knowledge. Having a viral upper respiratory infection on the day of the survey was negatively associated with knowledge. However, greater knowledge was not associated with more positive attitudes regarding possible public health interventions in a pandemic setting. Although 42% of patients were worried about avian influenza, only 22% trusted the Government to contain its spread. Most patients were wilting to wear a mask (82%), be quarantined (78%) or undergo mandatory vaccination (55%). Conclusion: Knowledge about avian influenza was poor in this mainly college-educated sample, but most patients had positive attitudes towards public health control measures that would be used in a pandemic scenario. Further studies are needed to inform education strategies and pandemic influenza planning. [ABSTRACT FROM AUTHOR]

Background. Despite the introduction of Centers for Disease Control and Prevention guidelines for their use, antiviral medications for influenza remain underutilized. Our objective in this study was to describe beliefs, attitudes, and knowledge regarding antiviral medication and vaccination for influenza among patients in an internal medicine clinic. Methods. We conducted a cross-sectional survey of adult patients in an internal medicine clinic from April through June 2006. Results. Two-hundred eighty patients completed the survey. Fifty-five percent received influenza vaccination for the most recent influenza season. Overall antiviral knowledge was poor. Of 8 antiviral knowledge questions, the mean percentage of correct answers was 40%; 1 (!1%) of the patients answered all questions correctly, and 47 (18%) answered all questions incorrectly. Only 37 (13%) of the patients reported calling their physician within 48 h after the onset of influenza-like symptoms. Patients with conditions associated with a high risk of complications from influenza were no more likely than other patients to be more knowledgeable about antiviral medication, nor were they more likely to report calling their physician within 48 h after symptom onset or to report receipt of influenza vaccination for the previous influenza season. Only 90 (37%) of the respondents were willing to pay 1$20 for antiviral medication, although 205 (84%) were willing to pay something. Conclusions. Patients are ill-informed about antiviral medication and its benefits, and medication costs may present a barrier to treatment. Physicians should discuss antiviral medication with patients who are at high risk for complications from influenza before the influenza season, and education programs for physicians and patients should be developed. [ABSTRACT FROM AUTHOR]

Objectives: To prevent pelvic inflammatory disease (PID), some experts recommend screening for sexually transmitted infection (STI) every 12 months, with more frequent screening suggested in higher-risk women. Nevertheless, the time from STI acquisition to PID development, possibly an important factor to consider in screening interval choice, is unknown and its influence on the effectiveness and cost-effectiveness of screening is unclear. Methods: Using a Markov model, we estimated PID cases averted and the incremental cost-effectiveness resulting from 6- or 12-month screening strategies for high-risk young women (6%/year infection risk, 2.8%/year PID risk with 12-month screening) while varying PID development time from 1 to 12 months after initial infection. Lower-risk women and alternative parameter values were examined in sensitivity analyses. Results: Relative to 12-month screening, 6-month screening decreases PID cases from 6.0% (1 month development time)to 19.4% (12 months); the incremental cost per quality-adjusted life-year (QALY) gained compared with the other strategies varies from $16,600 (12 months development time) to $31,800 (1 month) for high-risk women. In lower-risk women, every 6-month screening is more economically unfavorable, with greater costs per QALY gained at shorter PID development time. Conclusion: From a cost-effectiveness standpoint, uncertainty about PID development time is not a significant factor in choosing a screening interval in high-risk women, but could be important in lower-risk groups. Significant increases in PID cases averted occur with more frequent screening when PID development time is lengthened, which may allow estimation of this interval through the use of more sophisticated modeling techniques. [ABSTRACT FROM AUTHOR]

Objective: Home screening tests could eliminate several barriers to testing sexually transmitted diseases (STDs).Aim: To determine whether offering repeated home screening tests would increase the rate of testing for chlamydia and gonorrhoea in a high-risk sample of young women.Methods: In this randomised controlled trial, 403 young women (mean age 18.9 years, 70% black) with a recent STD or with STD-related risk factors were enrolled. Participants were recruited from clinics and high-prevalence neighbourhoods and then randomly assigned to receive either a home testing kit or an invitation to attend a medical clinic for testing at 6, 12 and 18 months after enrollment. Over 80% of women were followed for 2 years. The trial is registered with ClinicalTrials.gov, number NCT 00177437.Results: Of 197 women in the intervention group, 140 (71%) returned at least one home test and 25 of 249 (10%) home tests were positive. Women who received home screening tests completed significantly more STD tests overall (1.94 vs 1.41 tests per woman-year, p<0.001) and more STD tests in the absence of symptoms (1.18 vs 0.75 tests per woman-year, p<0.001). More women in the intervention group completed at least one test when asymptomatic (162 (82.2%) vs 117 (61.3%), p<0.001). The intervention was most effective among women recruited outside medical clinics. There was no significant difference in the overall rate of STDs detected.Conclusions: Home screening significantly increased the utilisation of chlamydia and gonorrhoea testing in this sample of high-risk young women, and thus represents a feasible strategy to facilitate STD testing in young women. [ABSTRACT FROM AUTHOR]

Quantum mechanics hinders our ability to determine the state of a physical system in two ways: individual measurements provide only partial information about the observed system (because of Heisenberg uncertainty), and measurements are themselves invasive—meaning that little or no refinement is achieved by further observation of an already measured system. Theoretical methods have been developed to maximize the information gained from a quantum measurement while also minimizing disturbance, but laboratory implementation of optimal measurement procedures is often difficult. The standard class of operations considered in quantum information theory tends to rely on superposition-basis and entangled measurements, which require high-fidelity implementation to be effective in the laboratory. Here we demonstrate that real-time quantum feedback can be used in place of a delicate quantum superposition, often called a ‘Schrödinger cat state’, to implement an optimal quantum measurement for discriminating between optical coherent states. Our procedure actively manipulates the target system during the measurement process, and uses quantum feedback to modify the statistics of an otherwise sub-optimal operator to emulate the optimal cat-state measurement. We verify a long-standing theoretical prediction and demonstrate feedback-mediated quantum measurement at its fundamental quantum limit over a non-trivial region of parameter space. [ABSTRACT FROM AUTHOR]

Resuspension of contaminated sediment can lead to the release of toxic compounds to surface waters where they are more bioavailable and mobile. Because the timeframe of particle resettling during such events is shorter than that needed to reach equilibrium, a kinetic approach is required for modeling the release process. Due to the current inability of common theoretical approaches to predict site-specific release rates, empirical algorithms incorporating the phenomenological assumption of biphasic, or fast and slow, release dominate the descriptions of nonpolar organic chemical release in the literature. Two first-order rate constants and one fraction are sufficient to characterize practically all of the data sets studied. These rate constants were compared to theoretical model parameters and functionalities, including chemical properties of the contaminants and physical properties of the sorbents, to determine if the trends incorporated into the hindered diffusion model are consistent with the parameters used in curve fitting. The results did not correspond to the parameter dependence of the hindered diffusion model. No trend in desorption rate constants, for either fast or slow release, was observed to be dependent on KOC or aqueous solubility for six and seven orders of magnitude, respectively. The same was observed for aqueous diffusivity and sediment fraction organic carbon. The distribution of kinetic rate constant values was approximately log-normal, ranging from 0.1 to 50 d-1 for the fast release (average ∼5 d-1) and 0.0001 to 0.1 d-1 for the slow release (average ∼0.03 d-1). The implications of these findings with regard to laboratory studies, theoretical desorption process mechanisms, and water quality modeling needs are presented and discussed. [ABSTRACT FROM AUTHOR]

Home testing for chlamydia and gonorrhea increases screening rates, but the cost consequences of this intervention are unclear. We examined the cost differences between home-based and clinic-based testing and the cost-effectiveness of home testing based on the DAISY study, a randomized controlled trial. Direct and indirect costs were estimated for home and clinic testing, and cost-effectiveness was calculated as cost per additional test performed. In the clinic testing group, direct costs were 49/test and indirect costs (the costs of seeking or receiving care) were 62/test. Home testing cost was 25/test. We found that home testing was cost saving when all testing for all patients was considered. However cost savings were not seen when only asymptomatic tests or when patient subgroups were considered. A home testing program could be cost saving, depending on whether changes in clinic testing frequency occur when home testing is available. [ABSTRACT FROM AUTHOR]

Objective: To assess women's satisfaction with a vaginal capsule containing human-derived, H2O2-producing Lactobacillus crispatus at completion of a randomized, placebo-controlled study for treatment of bacterial vaginosis (BV). Methods: Women aged 14–35 years with BV were randomized to Lactobacillus or placebo intravaginal capsule twice daily for 3 days monthly for 3 months. Attitudes were assessed with a standardized scale at the final follow-up visit, and associations of satisfaction with clinical and gram stain cure of BV were determined. Results: Four hundred twenty-four women were randomized at enrollment, and 232 (55%) provided data on satisfaction at the final visit. Overall, satisfaction with the capsule was high and was independent of subjects' race, age, and prior history of BV. Report of satisfaction with the capsule, belief that it contained healthy bacteria, and belief that its use improved vaginal health were directly related to clinical cure and to improved Nugent score. Except for women who had BV at the final follow-up visit, most subjects believed that the capsule contained healthy bacteria independent of any outcome reflecting cure. Willingness to use the capsule again was not significantly related to whether subjects experienced clinical cure or normalization of Nugent score at either visit. Adverse effects were rare and were largely related to a perceived difference in vaginal discharge. Conclusions: Satisfaction with an intravaginal capsule and positive beliefs about its use for BV treatment were prevalent, especially among women with a clinical and microbiological response to BV therapy. However, most women expressed willingness to use the product again regardless of clinical response. Acceptability of and interest in alternative BV treatments, such as L. crispatus intravaginal applications, are high. [ABSTRACT FROM AUTHOR]

The article describes the patterns of alcohol and drug use disorders among to young persons attending a public STD clinic and to determine their associations with sexual risk behaviors and STDs. Substance use disorders were common than confirmed STDs among young STD clinic attendees. STD clinics may be an appropriate setting to screen for and address substance use disorders in young persons.

Background: Testing of urine samples is noninvasive and could overcome several barriers to screening for chlamydial and gonococcal infections, but most test samples are obtained directly from the cervix or urethra. Purpose: To systematically review studies that assessed the sitivity and specificity of nucleic acid amplification tests for Chlamydia trachomatis and Neisseria gonorrhoeae in urine specimens and to compare test characteristics according to type of assay, site of sample collection, presence of symptoms, disease prevalence, and characteristics of the reference standard. Data Sources: Relevant studies in all languages were identified by searching the MEDLINE database (January 1991 to December 2004) and by hand-searching the references of identified articles and relevant journals. Study Selection: Studies were selected that evaluated 1 of 3 commercially available nucleic acid amplification tests, included data from tests of both a urine sample and a traditional sample (obtained from the cervix or urethra), and used an appropriate reference standard. Data Extraction: From 29 eligible studies, 2 investigators independently abstracted data on sample characteristics, reference standard, sensitivity, and specificity. Data Synthesis: Articles were assessed qualitatively and quantitatively. Summary estimates for men and women were calculated separately for chlamydial and gonococcal infections and were stratified by assay and presence of symptoms. The pooled study specificities of each of the 3 assays exceeded 97% when urine samples were tested, for both chlamydial infection and gonorrhea and in both men and women. The pooled study sensitivities for the polymerase chain reaction, transcription-mediated amplification, and strand displacement amplification assays, respectively, were 83.3%, 92.5%, and 79.9% for chlamydial infections in women; 84.0%, 87.7%, and 93.1 % for chlamydial infections in men; and 55.6%, 91.3%, and 84.9% for gonococcal infections in women. The pooled specificity of polymerase chain reaction to gonococcal infections in men was 90.4%. In subgroup analyses, the sensitivity did not vary according to the prevalence of infection or the presence of symptoms but did vary according to the reference standard used. Limitations: Few published studies present data on the transcription-mediated amplification or strand displacement amplification assays, and few studies report data from asymptomatic patients or low-prevalence groups. Conclusions: Results of nucleic acid amplification tests for C. trachomatis on urine samples are nearly identical to those obtained on samples collected directly from the cervix or urethra. Although all 3 assays can also be used to test for N. gonorrhoeae, the sensitivity of the polymerase chain reaction assay in women is too low to recommend its routine use to test for gonorrhea in urine specimens. [ABSTRACT FROM AUTHOR]

Objective/Goal: The objective of this study was to conduct a systematic review of published literature on the association between problematic alcohol consumption and sexually transmitted diseases (STDs). Design: Using a MEDLINE search (1995–2003) and article references, we identified articles that described measures of alcohol consumption and STDs and presented data on their association. For each eligible study, we classified the alcohol consumption measure as specific (problem drinking) or general, and examined study designs, study populations, STD measures, and results. Results: Of 42 eligible studies, 11 included specific measures of problem drinking, of which 8 found a significant association between alcohol consumption and at least 1 STD. The relationship did not appear to vary according to gender or pattern of alcohol consumption assessed. Conclusions: The literature supports an overall association between problematic alcohol consumption and STDs, although their causal relationship cannot be determined with certainty from these observational studies. The findings have implications for prevention planners, clinicians, and individual patients at risk of STDs. [ABSTRACT FROM AUTHOR]

Objective: To compare the ability of 3 brief alcohol screens (Alcohol Use Disorders Identification Test [AUDIT], CRAFFT, and CAGE) to identify adolescents and young adults with a current alcohol use disorder (AUD) and to determine whether there are gender-based or race-based differences in screening performance.Design, Participants, and Setting: Cross-sectional study of 358 young persons (55% males; 49% blacks; age range, 15-24 years; mean age, 20.6 years) who were attending an urban clinic for sexually transmitted diseases and reported alcohol use during the past year.Measurements: Receiver operating characteristic (ROC) curve analysis was used to determine the ability of the 3 screens to discriminate between participants with and without AUDs detected in the Structured Clinical Interview for DSM-IV (SCID).Results: One third (33%) of participants met Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria for a current AUD (24% with alcohol abuse and 9% with alcohol dependence). The AUDIT performed best at a cut score of 9 (sensitivity, 0.76; specificity, 0.79), CRAFFT at a cut score of 2 (sensitivity, 0.94; specificity, 0.33), and CAGE at a cut score of 1 (sensitivity, 0.69; specificity, 0.63). The AUDIT had the best overall performance (area under the curve [AUC], 0.84), followed closely by CRAFFT (AUC, 0.79) and then CAGE (AUC, 0.70). Performance of screens did not differ by gender. The AUDIT performed slightly better in whites than blacks, but no race-based differences were observed for the CAGE or CRAFFT.Conclusions: Clinicians should use the AUDIT or CRAFFT, rather than the CAGE, to screen young persons for AUDs. The AUDIT performs best, but its length may limit its utility in this setting. The CRAFFT is a suitable alternative, with excellent sensitivity and no gender-based or race-based differences. [ABSTRACT FROM AUTHOR]

This work itemizes and critically assesses several 1D and multi-dimensional nuclear magnetic resonance (NMR) techniques, in both the liquid (solvent suppression, APT, DEPT, INEPT, COSY, TOCSY, HSQC, HMQC, HMBC, NOESY, ROESY and others) and solid states (DP, SACP, RAMP-CP, CP-TOSS, MQ-DEPT, 2D 1H–13C HETCOR and others), which are relevant to the characterization of natural organic matter (NOM). The pros and cons of many of the discussed techniques are compared in an effort to provide guidance to the most beneficial utilization of these NMR instrumental techniques for researchers interested in gaining insight into various aspects of NOM. [ABSTRACT FROM AUTHOR]

Background and Objectives: Few data are available on the prevalence of and risk factors for sexually transmitted diseases (STDs) other than HIV in Brazil. Goal: The goal of this study was to determine the prevalence of HIV infection and other STDs in Brazilian women who seek HIV testing, investigate risk factors for these infections, and assess feasibility of screening in HIV test clinic settings. Study Design: We conducted a cross-sectional study of 200 women, aged 14 to 29 years, who attended an HIV testing site in central Rio de Janeiro. Participants completed a questionnaire and received testing for HIV, syphilis, chlamydia, and gonorrhea. Results: HIV and other STDs were common (HIV 8%, syphilis 6.5%, chlamydial infection 8%, and gonorrhea 9.5%). HIV was significantly associated with lower education and with having an HIVinfected partner. Other STDs were significantly associated with younger age at first intercourse, heavy alcohol consumption, and marijuana use. Conclusion: STDs appear to be substantial health problems among young Brazilian women seeking HIV testing. HIV testing sites in Brazil should consider offering screening and treatment for STDs and substance abuse as part of their HIV prevention services.

The Boreal forest fulvic acid known as Laurentian fulvic acid (LFA) has been interrogated by state of the art heteronuclear and 2D high resolution NMR techniques. It is shown that one can obtain very highly resolved and informative spectra of a traditionally fractionated material. It was possible to observe a proton coupled system of up to seven bonds in the TOCSY spectrum and 329 peaks in the ¹H,[sup 13]C-HSQC spectrum. It is found that the majority of the nitrogen in this sample is in the form of ammonium cations. From the combination of inverse-gated decoupling, APT, and INEPT [sup 13]C spectra of LFA it can be concluded that while the aromatic moieties of LFA are highly unfunctionalized, the carbohydrate moieties are highly functionalized. Proton coupled networks are observed in the TOCSY spectrum between and within the aliphatic, functionalized aliphatic, and heteroatom substituted regions and, to a lesser extent, also between the amine/aromatic and heteroatom substituted regions. The HMBC spectrum confirms that both the aliphatic and heteroatom moieties are highly functionalized with carboxylic and alcoholic functional groups, while the aromatic moieties are very sparsely functionalized with phenolic and carboxylic functionalities. Additionally, specific model molecular structures have been identified which are consistent with experimental evidence and are in full agreement with our previously derived meso-model based on solid-state [sup 13]C NMR data. Finally, some of the shortcomings of 2D liquidstate NMR for the characterization of humic materials are addressed. [ABSTRACT FROM AUTHOR]

This cross-sectional study sought to determine the prevalence of smoking, readiness to quit, and preferences for smoking cessation treatments among a sample of 236 homeless adults attending 9 sites serving homeless persons (mean age 41.8 years; 73% male). Two thirds (69%) were current smokers, of whom 37% reported readiness to quit smoking within the next 6 months. In bivariate analyses, persons were significantly ( P < .05) more likely to be ready to quit if they had tried to quit in the past and if they had social support to quit smoking. Nicotine replacement was the most commonly preferred assistance method (44%), and self-efficacy to quit (10-point scale) was significantly greater if assistance was available (7.3 vs 4.9; P < .001). The findings suggest an urgent need to develop and implement smoking cessation programs for homeless persons. [ABSTRACT FROM AUTHOR]

Evaluates the assessment of primary care physicians toward sexually transmitted diseases-related (STD) issues in Pennsylvania. Improvement of STD-prevention practices; Indication of clinical settings and counseling behaviors; Observation of the demographic characteristics.

Abstract. College students often delay or avoid seeking testing for sexually transmitted infections (STIs), even if the services are readily available. We used in-depth, semistructured interviews to survey 41 college students aged 18 to 23 years about factors that influence decisions about STI testing. We grouped statements into 9 themes that represent influences on the decision. The most frequently mentioned factors were negative consequences of testing and perceived vulnerability to infection; other issues that influenced decision making included perceived benefits, perceived severity of diseases, public knowledge and opinion, social norms, provider characteristics, test-site characteristics, and personal considerations. Social stigmas and negative consequences appear to represent significant barriers to college students' being tested, which could increase the risk of spreading infections to others. Clinicians and health educators should raise students' awareness of the need for screening and should work to reduce the barriers to screening, including social stigmas and negative consequences. [ABSTRACT FROM AUTHOR]

Objective: To examine the relation between problem drinking and medication adherence among persons with HIV infection.Design: Cross-sectional survey.Setting/participants: Two hundred twelve persons with HIV infection who visited 2 outpatient clinics between December 1997 and February 1998.Measurements and Main Results: Nineteen percent of subjects reported problem drinking during the previous month, 14% missed at least 1 dose of medication within the previous 24 hours, and 30% did not take their medications as scheduled during the previous week. Problem drinkers were slightly more likely to report a missed dose (17% vs 12 %, P =.38) and significantly more likely to report taking medicines off schedule (45% vs 26%, P =.02). Among drinking subtypes, taking medications off schedule was significantly associated with both heavy drinking (high quantity/frequency) (adjusted odds ratio [OR], 4.70; 95% confidence interval [95% CI], 1.49 to 14.84; P <.05) and hazardous drinking (adjusted OR, 2.64; 95% CI, 1.07 to 6.53; P <.05). Problem drinkers were more likely to report missing medications because of forgetting (48% vs 35%, P =.10), running out of medications (15% vs 8%, P =.16), and consuming alcohol or drugs (26 % vs 3 %, P <.001).Conclusion: Problem drinking is associated with decreased medication adherence, particularly with taking medications off schedule during the previous week. Clinicians should assess for alcohol problems, link alcohol use severity to potential adherence problems, and monitor outcomes in both alcohol consumption and medication adherence. [ABSTRACT FROM AUTHOR]

Introduction: Illicit drug use is a significant public health problem. Studies have shown a high prevalence of cocaine and cannabis use in transgender women (TGW). Objective: To describe the consumption patterns of cannabis and cocaine/crack use and variables associated with their use in TGW in Central Brazil. Methods: A cross-sectional study was conducted on TGW in Goiás, Brazil. Participants were recruited using a respondent-driven sampling method and were interviewed face-to-face about cannabis and crack-cocaine and the variables associated with them. The Alcohol Smoking and Substance Involvement Screening Test was used to assess substance use. Unweighted logistic regression was used to identify variables associated with cannabis and crack cocaine use. P-values < 0.05 were considered statistically significant. Results: A total of 440 transgender women participated in the study. Their median age was 25 years (interquartile range: 20.5–29.5 years). Most participants were single (85.5%) and had engaged in sex work in their lifetime (58.6%). Cannabis was reported by 68.9% and 53.4% of participants in their lifetime and in the past three months, respectively, and cocaine/crack use was reported by 59.8% and 44.1% of participants in their lifetime and the past three months, respectively. Of the participants, 10.2% reported high-risk cannabis use, and 9.1% reported high-risk cocaine/crack use. Furthermore, 35% of participants reported using both drugs. Previous physical violence (Adjusted Odds Ratio (AOR): 2.37), inconsistent condom uses during anal sex (AOR: 2.17), and moderate-/high-risk cocaine/crack use (AOR: 3.14) were associated with high-risk cannabis use. Previous sexual violence (AOR: 2.84), previous STI (AOR: 2.90), moderate-/high-risk cannabis (AOR: 3.82), and binge drinking (AOR; 3.28) were associated with high-risk cocaine/crack use. Conclusion: Our study found a high frequency, significant overlap in the use of cannabis and cocaine/crack use and violence associated with these drugs consumption among TGW, highlighting the urgent need for health policies for drug disorders among this socially marginalized group. [ABSTRACT FROM AUTHOR]

We used group-based trajectory models to identify 4 distinct trajectory patterns of adherence to preexposure prophylaxis (PrEP) among 20 696 users. Only 44.5% were consistently PrEP adherent, with younger age, being female, or having substance use disorder or depression associated with early discontinuation. Public health efforts are needed to improve PrEP adherence. [ABSTRACT FROM AUTHOR]

Pre-exposure prophylaxis (PrEP) use may be associated with condom use decisions. The current investigation examined sexual decision-making in the context of PrEP among young adult men who have sex with men (MSM) between 18 and 30 years old, using an explanatory sequential mixed methods design. For the quantitative aim, 99 MSM currently taking PrEP (i.e., PrEP-experienced) and 140 MSM not currently taking PrEP (i.e., PrEP-naive) completed an online survey, including the Sexual Delay Discounting Task (SDDT), which captures likelihood of condom use. For the qualitative aim, 15 people from each group were interviewed about their (1) conceptualizations of risky sex and (2) ways they manage their sexual risk. Participants were, on average, 25.69 years old (SD = 3.07) and 64% White. Results from the quantitative aim revealed, controlling for covariates, PrEP-experienced participants exhibited significantly lower likelihood of (1) using an immediately available condom and (2) waiting for a delayed condom (i.e., sexual delay discounting) compared to PrEP-naive participants. Qualitative themes explaining what young adult MSM consider to be risky sex included: (1) any sex as risky sex, (2) risky sex as "sex without a conversation," and (3) risky sex as sex with risk for physical harm. Themes on ways young adult MSM manage sexual risk were classified as proactive, reactive, and passive. Results suggest that PrEP use is related to condom use decisions. Taken together, quantitative differences in sexual delay discounting, but qualitatively similar conceptualizations and management of risky sex, suggest that the SDDT may be a useful tool in sex research to capture processes (i.e., delay discounting) underlying sexual decision-making that may be missed by traditional self-reports. Implications of results, including potentially providing (good quality) condoms with every PrEP prescription, and future research topics are discussed. [ABSTRACT FROM AUTHOR]

Examines Chlamydia trachomatis infection in college women with a polymerase chain reaction (PCR) assay. Factors associated with chlamydial infection; Testing characteristics of a PCR assay for chlamydial infection; Symptoms; Importance of screening young women for chlamydial infection.

Objectives. The purpose of this study was to determine whether county syphilis rates were increased along interstate Highway 95 (I-95) in North Carolina during a recent epidemic. Methods. Ecological data on syphilis cases, demographic data, highway data, and drug activity data were used to conduct a cross-sectional and longitudinal study of North Carolina counties from 1985 to 1994. Crude and adjusted incidence rate ratios (IRRs) were determined by means of standard and longitudinal Poisson regression models adjusted for sociodemographic factors and drug use. Results. Ten year syphilis rates in I-95 counties greatly exceeded rates in non-I-95 counties (38 vs 16 cases per 100 000 persons) and remained higher after adjustment for race, age, sex, poverty, large cities, and drug activity (adjusted IRR = 2.05, 95% confidence interval [CI] 1.84, 2.28). Syphilis rates were stable until 1989, when rates increased sharply in I-95 counties but remained stable in non-I-95 counties. Increased drug activity in I-95 counties preceded the rise in syphilis cases. conclusions. A better understanding of the relationship between highways and the spread of sexually transmitted diseases may guide future prevention interventions. [ABSTRACT FROM AUTHOR]

Application of optical diagnostic techniques and instruments in the high-temperature coal combustion environments of large-scale facilities requires a clear optical path into and out of the particle-laden gas stream for long periods of time. In this paper, we describe devices for making long-term optical measurements in the sonic and supersonic regions of a coal combustion flow where, in general, the gas stream is a high-speed flow at high temperature and pressure. The design and operation of the devices are discussed and schematics are presented. Successful operation of the devices for over 900 h demonstrates their long-term reliability. [ABSTRACT FROM AUTHOR]