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Background: Despite the known interplay between blood flow and function, to our knowledge, there is currently no minimally invasive method to monitor diaphragm hemodynamics. We used contrast-enhanced ultrasound to quantify relative diaphragm blood flow (Q˙ DIA ) in humans and assessed the technique's efficacy and reliability during graded inspiratory pressure threshold loading. We hypothesized that: (1) Q˙ DIA would linearly increase with pressure generation, and (2) that there would be good test-retest reliability and interanalyzer reproducibility., Research Question: Can we validate what is, to our knowledge, the first minimally invasive method to measure relative diaphragm blood flow in humans?, Study Design and Methods: Quantitative contrast-enhanced ultrasound of the costal diaphragm was performed in healthy participants (10 male participants, 6 female participants; mean age 28 ± 5 years; BMI 22.8 ± 2.0 kg/m) during unloaded breathing and three stages of loaded breathing on two separate days. Gastric and esophageal balloon catheters measured transdiaphragmatic pressure. Ultrasonography was performed during a constant-rate IV infusion of lipid-stabilized microbubbles following each stage. Ultrasound images were acquired after a destruction-replenishment sequence and diaphragm specific time-intensity data were used to determine Q˙ DIA by two individuals., Results: Transdiaphragmatic pressure for unloaded and each loading stage were 15.2 ± 0.8, 26.1 ± 0.8, 34.6 ± 0.8, and 40.0 ± 0.8 percentage of the maximum, respectively. Q˙ DIA increased with each stage of loading (3.1 ± 3.1, 6.9 ± 3.6, 11.0 ± 4.9, and 13.5 ± 5.4 acoustic units/s; P < .0001). The linear relationship between diaphragmatic flow and pressure was reproducible from day to day. Q˙ DIA had good to excellent test-retest reliability (0.86 [0.77, 0.92]; P < .0001) and excellent interanalyzer reproducibility (0.93 [0.90, 0.95]; P < .0001) with minimal bias., Interpretation: Relative Q˙ DIA measurements had valid physiological underpinnings, were reliable day-to-day, and were reproducible analyzer-to-analyzer. This study indicated that contrast-enhanced ultrasound is a viable, minimally invasive method for assessing costal Q˙ DIA in humans and may provide a tool to monitor diaphragm hemodynamics in clinical settings., Competing Interests: Financial/Nonfinancial Disclosures None declared., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The near-infrared spectroscopy (NIRS)-derived cerebral oximetry index (COx) has become popularized for non-invasive neuromonitoring of cerebrovascular function in post-cardiac arrest patients with hypoxic-ischemic brain injury (HIBI). We provide commentary on the physiologic underpinnings and assumptions of NIRS and the COx, potential confounds in the context of HIBI, and the implications for the assessment of cerebral autoregulation., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: J.D.B. is an R&D Consultant for Kent Imaging Inc. D.B.M, D.E.G., M.S.S. and R.L.H. report no conflicts of interest, financial or otherwise.

Rationale: Central sleep apnea (CSA) is pervasive during sleep at high altitude, disproportionately impacting men and associated with increased peripheral chemosensitivity. Objectives: We aimed to assess whether biological sex affects loop gain (LGn) and CSA severity during sleep over 9-10 days of acclimatization to 3,800 m. We hypothesized that CSA severity would worsen with acclimatization in men but not in women because of greater increases in LGn in men. Methods: Sleep studies were collected from 20 (12 male) healthy participants at low altitude (1,130 m, baseline) and after ascent to (nights 2/3, acute) and residence at high altitude (nights 9/10, prolonged). CSA severity was quantified as the respiratory event index (REI) as a surrogate of the apnea-hypopnea index. LGn, a measure of ventilatory control instability, was quantified using a ventilatory control model fit to nasal flow. Linear mixed models evaluated effects of time at altitude and sex on respiratory event index and LGn. Data are presented as contrast means with 95% confidence intervals. Results: REI was comparable between men and women at acute altitude (4.1 [-9.3, 17.5] events/h; P  = 0.54) but significantly greater in men at prolonged altitude (23.7 [10.3, 37.1] events/h; P  = 0.0008). Men had greater LGn than did women for acute (0.08 [0.001, 0.15]; P  = 0.047) and prolonged (0.17 [0.10, 0.25]; P  < 0.0001) altitude. The change in REI per change in LGn was significantly greater in men than in women (107 ± 46 events/h/LGn; P  = 0.02). Conclusions: The LGn response to high altitude differed between sexes and contributed to worsening of CSA over time in men but not in women. This sex difference in acclimatization appears to protect females from high altitude-related CSA. These data provide fundamental sex-specific physiological insight into high-altitude acclimatization in healthy individuals and may help to inform sex differences in sleep-disordered breathing pathogenesis in patients with cardiorespiratory disease.

Dead-space-associated rebreathing of expired air and heat trapping with use of surgical masks and N95 respirators may underlie anecdotal reports of adverse symptoms associated with medical face barriers. Limited data exist directly comparing the physiological effects of masks and respirators at rest. We assessed the short-term physiological effects of both barrier types over 60 min at rest, including face microclimate temperature, end-tidal gases, and venous blood acid-base variables. We recruited 34 participants into two trials: surgical masks ( n = 17) and N95 respirators ( n = 17). In a seated position, participants underwent a 10-min baseline without a barrier and then wore a standardized surgical mask or dome-shaped N95 respirator for 60 min, followed by a 10-min washout. We instrumented healthy human participants with a peripheral pulse oximeter ([Formula: see text]) and a nasal cannula connected to a dual gas analyzer for measurement of the pressure of end-tidal [Formula: see text] and [Formula: see text], with an associated temperature probe for face microclimate temperature. Venous (v) blood samples were obtained at baseline and following 60-min mask/respirator wearing to assess [Formula: see text], [HCO 3 - ]v and pHv. Compared with baseline during/following 60 min, temperature, [Formula: see text], [Formula: see text], and [HCO 3 - ]v were mildly but significantly higher, and [Formula: see text] and [Formula: see text] were significantly lower, but [Formula: see text] was unaffected. The magnitude of effects was similar between barrier types. Temperature and [Formula: see text] returned to baseline levels within 1-2 min following removal of the barrier. These mild physiological effects may underlie reports of qualitative symptoms while wearing masks or respirators. However, the magnitudes were mild, not physiologically relevant and reversed immediately with the removal of the barrier. NEW & NOTEWORTHY Anecdotal reports suggest mild physiological effects of wearing surgical masks and/or N95 respirators, including heat trapping and rebreathing of expired air. There are limited data directly comparing the physiological effects of wearing medical barriers at rest. We found that the time course and magnitude of changes to face microclimate temperature, end-tidal gases, and venous blood gases and acid-base variables were mild in magnitude, not physiologically relevant, equivalent between barrier types, and immediately reversible on removal.

Cerebral hypoxia is a serious consequence of several cardiorespiratory illnesses. Measuring the retinal microvasculature at high altitude provides a surrogate for cerebral microvasculature, offering potential insight into cerebral hypoxia in critical illness. In addition, although sex-specific differences in cardiovascular diseases are strongly supported, few have focused on differences in ocular blood flow. We evaluated the retinal microvasculature in males ( n = 11) and females ( n = 7) using functional optical coherence tomography at baseline (1,130 m) ( day 0 ), following rapid ascent ( day 2 ), and prolonged exposure ( day 9 ) to high altitude (3,800 m). Retinal vascular perfusion density (rVPD; an index of total blood supply), retinal thickness (RT; reflecting vascular and neural tissue volume), and arterial blood were acquired. As a group, rVPD increased on day 2 versus day 0 ( P < 0.001) and was inversely related to [Formula: see text] ( R 2  = 0.45; P = 0.006). By day 9 , rVPD recovered to baseline but was significantly lower in males than in females ( P = 0.007). RT was not different on day 2 versus day 0 ( P > 0.99) but was reduced by day 9 relative to day 0 and day 2 ( P < 0.001). RT changes relative to day 0 were inversely related to changes in [Formula: see text] on day 2 ( R 2  = 0.6; P = 0.001) and day 9 ( R 2  = 0.4; P = 0.02). RT did not differ between sexes. These data suggest differential time course and regulation of the retina during rapid ascent and prolonged exposure to high altitude and are the first to demonstrate sex-specific differences in rVPD at high altitude. The ability to assess intact microvasculature contiguous with the brain has widespread research and clinical applications. NEW & NOTEWORTHY Measuring the retinal microvasculature at high altitude provides a surrogate for cerebral microvasculature, offering potential insight into consequence of cerebral hypoxia in critical illness. This study demonstrates dynamic regulation of the retina during rapid ascent and prolonged exposure to high altitude and is the first to demonstrate sex-specific differences in retinal microvasculature at high altitude. The ability to dynamically assess intact microvasculature contiguous with the brain has widespread research and clinical applications.

The central respiratory chemoreceptor complex (CCRC) is comprised of brainstem neurons and surrounding interoceptors, which collectively increase ventilation in response to elevated brainstem tissue CO 2 /[H + ] (i.e., central chemoreflex; CCR). The extent that the CCRC detects/responds to other metabolically related chemostimuli is unknown. We aimed to test the effects of acute oral glucose ingestion on CCR reactivity in heathy human participants (n = 38). We instrumented participants with a pneumotachometer (minute ventilation) and a gas sample line connected to a dual gas analyzer (pressure of end-tidal CO 2 ). Following a baseline (BL) period and capillary blood [glucose] (BG) sample, fasted (F) participants underwent a modified hyperoxic rebreathing test to assess CCR reactivity. Participants then consumed a 75 g standard glucose beverage (glucose loaded; GL). Following 30-min, they underwent a second BL, BG sample and hyperoxic rebreathing test. BG and metabolic rate were higher in GL, confirming the metabolic stimulus. However, the ventilatory recruitment threshold and the CCR responses were unchanged between F and GL states., (Copyright © 2021 Elsevier B.V. All rights reserved.)

High-altitude exposure results in a hyperventilatory-induced respiratory alkalosis followed by renal compensation (bicarbonaturia) to return arterial blood pH (pHa) toward sea-level values. However, acid-base balance has not been comprehensively examined in both lowlanders and indigenous populations-where the latter are thought to be fully adapted to high altitude. The purpose of this investigation was to compare acid-base balance between acclimatizing lowlanders and Andean and Sherpa highlanders at various altitudes (∼3,800, ∼4,300, and ∼5,000 m). We compiled data collected across five independent high-altitude expeditions and report the following novel findings: 1 ) at 3,800 m, Andeans ( n = 7) had elevated pHa compared with Sherpas ( n = 12; P < 0.01), but not to lowlanders ( n = 16; 9 days acclimatized; P = 0.09); 2) at 4,300 m, lowlanders ( n = 16; 21 days acclimatized) had elevated pHa compared with Andeans ( n = 32) and Sherpas ( n = 11; both P < 0.01), and Andeans had elevated pHa compared with Sherpas ( P = 0.01); and 3 ) at 5,000 m, lowlanders ( n = 16; 14 days acclimatized) had higher pHa compared with both Andeans ( n = 66) and Sherpas ( n = 18; P < 0.01, and P = 0.03, respectively), and Andean and Sherpa highlanders had similar blood pHa ( P = 0.65). These novel data characterize acid-base balance acclimatization and adaptation to various altitudes in lowlanders and indigenous highlanders. NEW & NOTEWORTHY Lowlander, Andean, and Sherpa arterial blood data were combined across five independent high-altitude expeditions in the United States, Nepal, and Peru to assess acid-base status at ∼3,800, ∼4,300, and ∼5,000 m. The main finding was that Andean and Sherpa highlander populations have more acidic arterial blood, due to elevated arterial carbon dioxide and similar arterial bicarbonate compared with acclimatizing lowlanders at altitudes ≥4,300 m.

Central sleep apnea (CSA) is characterized by periodic breathing (PB) during sleep, defined as intermittent periods of apnea/hypopnea and hyperventilation, with associated acute fluctuations in oxyhemoglobin saturation (SO 2 ). CSA has an incidence of ∼50% in heart failure patients but is universal at high altitude (HA; ≥2,500 m), increasing in severity with further ascent and/or time at altitude. However, whether PB is adaptive, maladaptive, or neutral with respect to sleeping SO 2 at altitude is unclear. We hypothesized that PB severity would improve mean sleeping SO 2 during acclimatization to HA due to relative, intermittent hyperventilation subsequent to each apnea. We utilized portable sleep monitors to assess the incidence and severity of CSA via apnea-hypopnea index (AHI) and oxygen desaturation index (ODI), and peripheral oxygen saturation ([Formula: see text]) during sleep during two ascent profiles to HA in native lowlanders: 1 ) rapid ascent to and residence at 3,800 m for 9 days/nights ( n = 21) and 2 ) incremental ascent to 5,160 m over 10 days/nights ( n = 21). In both ascent models, severity of AHI and ODI increased and mean sleeping [Formula: see text] decreased, as expected. However, during sleep on the last night/highest altitude of both ascent profiles, neither AHI nor ODI were correlated with mean sleeping [Formula: see text] . In addition, mean sleeping [Formula: see text] was not significantly different between high and low CSA. These data suggest that CSA is neither adaptive nor maladaptive with regard to mean oxygen saturation during sleep, owing to the relative hyperventilation between apneas, likely correcting transient apnea-mediated oxygen desaturation and maintaining mean oxygenation. NEW & NOTEWORTHY Central sleep apnea (CSA) is universal during ascent to high altitude, with intermittent and transient fluctuations in oxygen saturation, but the consequences on mean sleeping blood oxygenation are unclear. We assessed indices of CSA and mean sleeping peripheral oxygen saturation ([Formula: see text]) during ascent to high altitude using two ascent profiles: rapid ascent and residence at 3,800 m and incremental ascent to 5,160 m. The severity of CSA was not correlated with mean sleeping [Formula: see text] with ascent.

Rapid ascent to high altitude imposes an acute hypoxic and acid-base challenge, with ventilatory and renal acclimatization countering these perturbations. Specifically, ventilatory acclimatization improves oxygenation, but with concomitant hypocapnia and respiratory alkalosis. A compensatory, renally mediated relative metabolic acidosis follows via bicarbonate elimination, normalizing arterial pH(a). The time course and magnitude of these integrated acclimatization processes are highly variable between individuals. Using a previously developed metric of renal reactivity (RR), indexing the change in arterial bicarbonate concentration (Δ[HCO 3 - ]a; renal response) over the change in arterial pressure of CO 2 (Δ[Formula: see text]; renal stimulus), we aimed to characterize changes in RR magnitude following rapid ascent and residence at altitude. Resident lowlanders ( n = 16) were tested at 1,045 m ( day [ D ] 0 ) prior to ascent, on D2 within 24 h of arrival, and D9 during residence at 3,800 m. Radial artery blood draws were obtained to measure acid-base variables: [Formula: see text], [HCO 3 - ]a, and pHa. Compared with D0 , [Formula: see text] and [HCO 3 - ]a were lower on D2 ( P < 0.01) and D9 ( P < 0.01), whereas significant changes in pHa ( P = 0.072) and RR ( P = 0.056) were not detected. As pHa appeared fully compensated on D2 and RR did not increase significantly from D2 to D9 , these data demonstrate renal acid-base compensation within 24 h at moderate steady-state altitude. Moreover, RR was strongly and inversely correlated with ΔpHa on D2 and D9 ( r ≤ -0.95; P < 0.0001), suggesting that a high-gain renal response better protects pHa. Our study highlights the differential time course, magnitude, and variability of integrated ventilatory and renal acid-base acclimatization following rapid ascent and residence at high altitude. NEW & NOTEWORTHY We assessed the time course, magnitude, and variability of integrated ventilatory and renal acid-base acclimatization with rapid ascent and residence at 3,800 m. Despite reductions in [Formula: see text] upon ascent, pHa was normalized within 24 h of arrival at 3,800 m through renal compensation (i.e., bicarbonate elimination). Renal reactivity (RR) was unchanged between days 2 and 9 , suggesting a lack of plasticity at moderate steady-state altitude. RR was strongly correlated with ΔpHa, suggesting that a high-gain renal response better protects pHa.

New Findings: What is the central question of this study? What is the relative contribution of a putative tonic splenic contraction to the haematological acclimatization process during high altitude ascent in native lowlanders? What is the main finding and its importance? Spleen volume decreased by -14.3% (-15.2 ml) per 1000 m ascent, with an attenuated apnoea-induced [Hb] increase, attesting to a tonic splenic contraction during high altitude ascent. The [Hb]-enhancing function of splenic contraction may contribute to restoring oxygen content early in the acclimatization process at high altitude., Abstract: Voluntary apnoea causes splenic contraction and reductions in heart rate (HR; bradycardia), and subsequent transient increases in haemoglobin concentration ([Hb]). Ascent to high altitude (HA) induces systemic hypoxia and reductions in oxygen saturation ( S p O 2 ), which may cause tonic splenic contraction, which may contribute to haematological acclimatization associated with HA ascent. We measured resting cardiorespiratory variables (HR, S p O 2 , [Hb]) and resting splenic volume (via ultrasound) during incremental ascent from 1400 m (day 0) to 3440 m (day 3), 4240 m (day 7) and 5160 m (day 10) in non-acclimatized native lowlanders during assent to HA in the Nepal Himalaya. In addition, apnoea-induced responses in HR, S p O 2 and splenic volume were measured before and after two separate voluntary maximal apnoeas (A1-A2) at 1400, 3440 and 4240 m. Resting spleen volume decreased -14.3% (-15.2 ml) per 1000 m with ascent, from 140 ± 41 ml (1400 m) to 108 ± 28 ml (3440 m; P > 0.99), 94 ± 22 ml (4240 m; P = 0.009) and 84 ± 28 ml (5160 m; P = 0.029), with concomitant increases in [Hb] from 125 ± 18.3 g l -1 (1400 m) to 128 ± 10.4 g l -1 (3440 m), 138.8 ± 12.7 g l -1 (4240 m) and 157.5 ± 8 g l -1 (5160 m; P = 0.021). Apnoea-induced splenic contraction was 50 ± 15 ml (1400 m), 44 ± 17 ml (3440 m; P > 0.99) and 26 ± 8 ml (4240 m; P = 0.002), but was not consistently associated with increases in [Hb]. The apnoea-induced bradycardia was more pronounced at 3440 m (A1: P = 0.04; A2: P = 0.094) and at 4240 m (A1: P = 0.037 A2: P = 0.006) compared to values at 1400 m. We conclude that hypoxia-induced splenic contraction at rest (a) may contribute to restoring arterial oxygen content through its [Hb]-enhancing contractile function and (b) eliminates further apnoea-induced [Hb] increases in hypoxia. We suggest that tonic splenic contraction may contribute to haematological acclimatization early in HA ascent in humans., (© 2020 The Authors. Experimental Physiology © 2020 The Physiological Society.)

New Findings: What is the central question of this study? We assessed the utility of a new metric for quantifying ventilatory acclimatization to high altitude, derived from differential ascent and descent steady-state cardiorespiratory variables (i.e. hysteresis). Furthermore, we aimed to investigate whether the magnitude of cardiorespiratory hysteresis was associated with the development of acute mountain sickness. What is the main finding and its importance? Hysteresis in steady-state cardiorespiratory variables quantifies ventilatory acclimatization to high altitude. The magnitude of cardiorespiratory hysteresis during ascent to and descent from high altitude was significantly related to the development of symptoms of acute mountain sickness. Hysteresis in steady-state chemoreflex drive can provide a simple, non-invasive method of tracking ventilatory acclimatization to high altitude., Abstract: Maintenance of arterial blood gases is achieved through sophisticated regulation of ventilation, mediated by central and peripheral chemoreflexes. Respiratory chemoreflexes are important during exposure to high altitude owing to the competing influence of hypoxia and hypoxic hyperventilation-mediated hypocapnia on steady-state ventilatory drive. Inter-individual variability exists in ventilatory acclimatization to high altitude, potentially affecting the development of acute mountain sickness (AMS). We aimed to quantify ventilatory acclimatization to high altitude by comparing differential ascent and descent values (i.e. hysteresis) in steady-state cardiorespiratory variables. We hypothesized that: (i) the hysteresis area formed by cardiorespiratory variables during ascent and descent would quantify the magnitude of ventilatory acclimatization; and (ii) larger hysteresis areas would be associated with lower AMS symptom scores during ascent. In 25 healthy, acetazolamide-free trekkers ascending to and descending from 5160 m, cardiorespiratory hysteresis was measured in the partial pressure of end-tidal CO 2 , peripheral oxygen saturation, minute ventilation, chemoreceptor stimulus index (end-tidal CO 2 /peripheral oxygen saturation) and the calculated steady-state chemoreflex drive (SS-CD; minute ventilation/chemoreceptor stimulus index) using portable devices (capnograph, peripheral pulse oximeter and respirometer, respectively). Symptoms of AMS were assessed daily using the Lake Louise questionnaire. We found that: (i) ascent-descent hysteresis was present in all cardiorespiratory variables; (ii) SS-CD is a valid metric for tracking ventilatory acclimatization to high altitude; and (iii) the highest AMS scores during ascent exhibited a significant, moderate and inverse correlation with the magnitude of SS-CD hysteresis (r s  = -0.408, P = 0.043). We propose that ascent-descent hysteresis is a new and feasible way to quantify ventilatory acclimatization in trekkers during high-altitude exposure., (© 2020 The Authors. Experimental Physiology © 2020 The Physiological Society.)

Professional social work has long been concerned with social justice, social policy, and the relationship between social treatment and social control. However, at times, potential threats to social cohesion become exaggerated in the service of supporting suppressive policies. British sociologist Stanley Cohen referred to such periods as moral panics, which assign unwarranted blame and stigma to sociopolitically weaker, unpopular groups. By constructing those associated with a given social problem as deviant and downplaying underlying structural causes, moral panics foster the enactment of social policies that entrench social disparity and injustice. Understanding how moral panics influence perceptions of social problems and resultant policies will enable social workers to identify whether particular societal groups are unjustly targeted. By synthesizing theoretical and empirical literature on moral panics in U.S. policy arenas relevant to social workers (such as illicit drugs, sexuality, and immigration), this article offers guidance for practitioners, policy advocates, and researchers on assessing their presence., (© 2016 National Association of Social Workers.)

Young, gay, and bisexual men (YGBM) are at increased risk of family rejection, which is related to HIV infection. What remains unknown is how family rejection leads to HIV risk. In this exploratory study, qualitative interviews were conducted with 21 HIV-positive YGBM aged 18 to 24. Most participants reported family rejection, which decreased instrumental and emotional support and resulted in participants using riskier ways to support themselves, such as engaging in survival sex. Conceptualizing the findings using a family systems framework, we present a tentative conceptual model to describe the potential relationships between family rejection and HIV risk for YGBM.

The HIV/AIDS epidemic is a health crisis among Black men who have sex with men (MSM). HIV-related stigma presents a primary barrier to sexual communication and effective HIV prevention. Using in-depth, qualitative interviews conducted with 20 HIV-positive Black MSM between 2007 and 2008 in Chicago, Illinois, we explored the themes related to HIV-related stigma and the underlying messages HIV-positive Black MSM receive regarding their status. Stigmatizing messages stem from family, churches, and the gay community and from negative, internalized, beliefs HIV-positive Black MSM held about infected individuals before their own infection. HIV stigma influences sexual silence around HIV disclosure, especially to sexual partners.

Purpose: There is little research on the impact of role models on health outcomes for lesbian, gay, bisexual, and transgender (LGBT) youth. This exploratory study describes the presence and availability of LGBT-affirming role models, and examines the relationship between the accessibility of role models and health outcomes among a community-based sample of LGBT youth., Methods: A convenience sample of 496 ethnically diverse, 16-24-year-old LGBT youth was recruited to complete a computer-assisted interview, using standardized instruments validated with adolescents. The prevalence and characteristics of role models were described. Differences in subgroup distribution were assessed using Pearson χ(2) test (p < .05). Differences in health outcomes for those with and without role models and the nature of those role models were determined using analysis of covariance models, with post hoc Bonferroni tests to probe significant global findings., Results: Sixty percent of the participants reported having a role model, with younger participants significantly more likely to report having a role model. A majority of the participants reported having inaccessible role models, especially among younger participants. The presence and accessibility of a role model did not have a significant relationship to binge drinking, drug use, or sexually transmitted infection diagnoses; however, participants with inaccessible role models showed increased psychological distress versus those with accessible or no role models., Conclusions: Inaccessible role models may not be sufficient for protecting youth from negative outcomes, and formal mechanisms for connecting LGBT youth with caring adults who can serve as role models, such as mentoring programs, are critical., (Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

This study explores community violence exposures among African American adolescents and whether coping strategies were gendered. In-depth interviews are conducted with a sample of 32 African American high school students. Data are analyzed using a thematic analysis. The primary forms of violence exposures are physical attacks, fighting, and incidents involving police, gun violence, and murders. Boys report more exposure to violence as victims and witnesses, whereas girls are more likely to hear about violent acts. Coping styles range from "getting through," which included both an acceptance of community conditions; "getting along," which included self-defense techniques; "getting away," which included avoidance coping strategies; and "getting back," which consisted of confrontational coping strategies. Boys report more confrontational coping styles than are girls, who utilized more avoidance approaches. Widespread school-based interventions are warranted, given the high prevalence of community violence exposure among these youth and may provide important supports for coping against such trauma.

Little is known about ethnic differences in HIV-disclosure to sexual partners or the relationship between HIV-disclosure and sexual risk. Differences in HIV-disclosure rates between African-American and White men who have sex with men (MSM) were analyzed using data from the Treatment Advocacy Program. In general, the findings suggest that African-Americans are less likely than Whites to disclose their HIV status to sexual partners. The findings also suggest that the African-American participants who disclosed to HIV-negative partners were significantly less likely to engage in unprotected anal sex with HIV-negative partners and partners whose HIV status was unknown than those participants who did not disclosure to HIV-negative partners. Although HIV-disclosure appears to be an important factor to consider in HIV-prevention efforts, there are unique factors that influence HIV-disclosure decisions for African-American MSM. Interventions should consider these unique challenges before focusing on HIV-disclosure as a primary tool for reducing the transmission of HIV.

HIV/AIDS continues to disproportionately impact men who have sex with men (MSM). Advances in highly active antiretroviral therapies (HAART) have successfully helped HIV-infected individuals lead longer, healthier, and presumably more sexually active lives. Consequently, secondary prevention approaches aimed at reducing the rate of HIV transmission have raised important questions about the role of sexual communication, namely HIV disclosure, as a primary target for intervention. This paper proposes a conceptual model of HIV disclosure in casual sexual encounters among MSM informed by Goffman's work on stigma and based on existing empirical research. The article concludes with an agenda for research based in this integrative model.

This study explored the beliefs of African American male adolescents concerning the high rates of HIV infection among their peers and their reasons for those beliefs. In-depth interviews were conducted with a sample of 16 male African Americans, and a thematic analysis of the data was conducted. Half of the participants believed that peers were not becoming infected at higher rates than white youths and reported high rates of sexual risk taking. Conspiracy beliefs and high rates of sexual adventurism for all teenagers were among the reasons offered to support this belief. Participants who believed the uneven incidence rates reported low levels of sexual risk taking. These participants identified early and unsafe sexual activity -- in conjunction with social factors such as negative peer and media influences, poor parental supervision, and dangerous neighborhood environments -- as contributing reasons for these disparate rates. Sexual behaviors were markedly different among both groups. The implications of these findings are discussed in the context of culturally relevant approaches to prevention of HIV infection among this group.