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INTRODUCTION: The management of skull base malignancies continues to evolve with improvements in surgical technique, advances in radiation delivery and novel systemic agents. METHODS: In this review, we aim to discuss in detail the management of common skull base pathologies which typically require multimodality therapy, focusing on the radiotherapeutic aspects of care. RESULTS: Technological advances in the administration of radiation therapy have led to a wide variety of different treatment strategies for the treatment of skull base malignances, with outcomes summarized herein. CONCLUSION: Radiation treatment plays a key and critical role in the management of patients with skull base tumors. Recent advancements continue to improve the risk/benefit ratio for radiotherapy in this setting.
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Radioterapia/métodos , Neoplasias de la Base del Cráneo/radioterapia , Animales , Manejo de la Enfermedad , Humanos , Neoplasias de la Base del Cráneo/patologíaRESUMEN
Accurate measurement of the thermal temperature in inertially confined fusion plasmas is essential for characterizing ignition performance and validating the basic physics understanding of the stagnation conditions. We present experimental results from cryogenic deuterium-tritium implosions on the National Ignition Facility using a differential filter spectrometer designed to measure the thermal electron temperature from x-ray continuum emission from the stagnated plasma. Furthermore, electron temperature measurements, used in conjunction with the Doppler-broadened DT neutron spectra, allow one to infer the partition of energy in the hot spot between internal energy and unconverted kinetic energy.
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Hydrodynamic instabilities can cause capsule defects and other perturbations to grow and degrade implosion performance in ignition experiments at the National Ignition Facility (NIF). Here, we show the first experimental demonstration that a strong unsupported first shock in indirect drive implosions at the NIF reduces ablation front instability growth leading to a 3 to 10 times higher yield with fuel ρR>1 g/cm(2). This work shows the importance of ablation front instability growth during the National Ignition Campaign and may provide a path to improved performance at the high compression necessary for ignition.
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First measurements of the in-flight shape of imploding inertial confinement fusion (ICF) capsules at the National Ignition Facility (NIF) were obtained by using two-dimensional x-ray radiography. The sequence of area-backlit, time-gated pinhole images is analyzed for implosion velocity, low-mode shape and density asymmetries, and the absolute offset and center-of-mass velocity of the capsule shell. The in-flight shell is often observed to be asymmetric even when the concomitant core self-emission is round. A â¼ 15 µm shell asymmetry amplitude of the Y(40) spherical harmonic mode was observed for standard NIF ICF hohlraums at a shell radius of â¼ 200 µm (capsule at â¼ 5× radial compression). This asymmetry is mitigated by a â¼ 10% increase in the hohlraum length.
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Modelos Teóricos , Radiografía/métodos , Simulación por Computador , Germanio/química , Oro/química , Termodinámica , Rayos XRESUMEN
OBJECTIVE: This study examined public perceptions of obesity-related public health media campaigns with specific emphasis on the extent to which campaign messages are perceived to be motivating or stigmatizing. METHOD: In summer 2011, data were collected online from a nationally representative sample of 1014 adults. Participants viewed a random selection of 10 (from a total of 30) messages from major obesity public health campaigns from the United States, the United Kingdom and Australia, and rated each campaign message according to positive and negative descriptors, including whether it was stigmatizing or motivating. Participants also reported their familiarity with each message and their intentions to comply with the message content. RESULTS: Participants responded most favorably to messages involving themes of increased fruit and vegetable consumption, and general messages involving multiple health behaviors. Messages that have been publicly criticized for their stigmatizing content received the most negative ratings and the lowest intentions to comply with message content. Furthermore, messages that were perceived to be most positive and motivating made no mention of the word 'obesity' at all, and instead focused on making healthy behavioral changes without reference to body weight. CONCLUSION: These findings have important implications for framing messages in public health campaigns to address obesity, and suggest that certain types of messages may lead to increased motivation for behavior change among the public, whereas others may be perceived as stigmatizing and instill less motivation to improve health.
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Peso Corporal , Comunicación en Salud/métodos , Promoción de la Salud , Motivación , Obesidad/prevención & control , Salud Pública , Opinión Pública , Estereotipo , Adulto , Australia/epidemiología , Conducta Alimentaria , Femenino , Conductas Relacionadas con la Salud , Comunicación en Salud/ética , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud/ética , Humanos , Estilo de Vida , Masculino , Medios de Comunicación de Masas , Obesidad/epidemiología , Obesidad/psicología , Percepción Social , Reino Unido/epidemiología , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Research demonstrates that health providers express negative attitudes toward overweight and obese patients that can be conveyed through weight-related language, yet little is known about people's perceptions of weight-related language used by providers. The current study examined public preferences and perceptions of weight-based terminology used by health-care providers to describe excess weight. METHOD: A national sample of American adults (N=1064) completed an online survey to assess perceptions and preferences associated with 10 common terms to describe body weight. Participants rated how much they perceived each term to be desirable, stigmatizing, blaming or motivating to lose weight (using five-point Likert scales), and how they would react if stigmatized by their doctor's reference to their weight. RESULTS: The terms 'weight' (3.43, 95% confidence interval (CI) 3.35-3.50) and 'unhealthy weight' (3.24, 95% CI 3.15-3.33) were rated most desirable, and the terms 'unhealthy weight' (3.77, 95% CI 3.69-3.84) and 'overweight' (3.51, 95% CI 3.43-3.58) were rated most motivating to lose weight. The terms 'morbidly obese', 'fat' and 'obese' were rated as the most undesirable (95% CI 1.61-2.06), stigmatizing (95% CI 3.66-4.05) and blaming (95% CI 3.62-3.94) language used by health providers. Notably, participant ratings were consistent across socio-demographic variables and body weight categories. A total of 19% of participants reported they would avoid future medical appointments and 21% would seek a new doctor if they felt stigmatized about their weight from their doctor. CONCLUSION: This study advances our understanding of why individuals prefer particular weight-related terms, and how patients may react if their provider uses stigmatizing language to refer to their weight. It also offers suggestions for practical strategies that providers can use to improve discussions about weight-related health with patients.
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Comunicación , Motivación , Obesidad , Percepción Social , Estereotipo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Peso Corporal , Femenino , Personal de Salud/psicología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/psicología , Relaciones Médico-Paciente , Autoimagen , Clase Social , Terminología como Asunto , Estados UnidosRESUMEN
Negative magnetic shear is found to suppress electron turbulence and improve electron thermal transport for plasmas in the National Spherical Torus Experiment (NSTX). Sufficiently negative magnetic shear results in a transition out of a stiff profile regime. Density fluctuation measurements from high-k microwave scattering are verified to be the electron temperature gradient (ETG) mode by matching measured rest frequency and linear growth rate to gyrokinetic calculations. Fluctuation suppression under negligible E×B shear conditions confirm that negative magnetic shear alone is sufficient for ETG suppression. Measured electron temperature gradients can significantly exceed ETG critical gradients with ETG mode activity reduced to intermittent bursts, while electron thermal diffusivity improves to below 0.1 electron gyro-Bohms.
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This study sought to identify predictors of HIV disclosure and serodiscordant unprotected anal intercourse (SDUAI) among HIV-positive men who have sex with men (MSM). Between January 2005 and April 2006, 675 HIV-positive MSM were recruited into the Positive Connections intervention trial held in six US cities with intentional over-sampling of HIV-positive MSM of Color (74%) and men engaging in unprotected anal intercourse (UAI) in the previous year. Baseline survey data showed 30 and 31%, respectively, of participants disclosed to none or some of their secondary sex partners in the last 90 days. Greater disclosure to secondary partners was associated with having fewer sexual partners, being extremely out as MSM, longer HIV diagnosis, knowledge of CD4 count, detectable viral load and being white. Disclosure to all secondary partners was associated with lower SDUAI. Recommendations for prevention for HIV-positive MSM include the promotion of serodisclosure to all secondary partners and increasing comfort with, and outness about, one's sexuality.
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Síndrome de Inmunodeficiencia Adquirida/psicología , Seropositividad para VIH/psicología , Autorrevelación , Parejas Sexuales/psicología , Sexo Inseguro/estadística & datos numéricos , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Adulto , Seropositividad para VIH/epidemiología , Seropositividad para VIH/transmisión , Conocimientos, Actitudes y Práctica en Salud , Homosexualidad Masculina/psicología , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Revelación de la Verdad , Estados Unidos/epidemiologíaRESUMEN
OBJECTIVES: The aim of this study was to determine the efficacy of implantable cardioverter-defibrillator (ICD) therapy in survivors of sudden cardiac death in whom no ventricular arrhythmias can be induced with programmed electrical stimulation. BACKGROUND: Survivors of sudden cardiac death in whom ventricular arrhythmias cannot be induced with programmed electrical stimulation remain at risk for recurrence of serious arrhythmias. Optimal protection to prevent sudden death in these patients is uncertain. This study compares survival in the subset of survivors of sudden cardiac death with that of patients treated with or without an ICD. METHODS: A retrospective study was performed on 194 consecutive survivors of primary sudden death who had < or = 6 beats of ventricular tachycardia induced with programmed electrical stimulation with at least three extrastimuli. Ninety-nine patients received an ICD and 95 did not. RESULTS: There were no significant differences between the two groups in presenting rhythm, number of prior myocardial infarctions or use of antiarrhythmic agents. Patients treated with an ICD were younger (55 +/- 16 vs. 59 +/- 11 years, p = 0.03) and had a lesser incidence of coronary artery disease (48% vs. 63%, p = 0.04) and a lower ejection fraction (0.43 +/- 0.16 vs. 0.48 +/- 0.18, p = 0.04). There were no significant differences between the groups in the use of revascularization procedures or antiarrhythmic agents after the sudden cardiac death. Patients treated with an ICD had an improvement in sudden cardiac death-free survival (p = 0.04) but the overall survival rate did not differ from that of the patients not so treated (p = 0.91). A multivariate regression analysis that adjusted for the observed differences between the groups did not alter these results. CONCLUSIONS: Survivors of sudden cardiac death in whom no arrhythmias could be induced with programmed electrical stimulation remained at risk for arrhythmia recurrence. Although the proportion of deaths attributed to arrhythmias was lower in the patients treated with an ICD, this therapy did not significantly improve overall survival.
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Desfibriladores Implantables , Paro Cardíaco/terapia , Análisis Actuarial , Adulto , Anciano , Estimulación Cardíaca Artificial , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Femenino , Estudios de Seguimiento , Paro Cardíaco/complicaciones , Paro Cardíaco/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Tasa de Supervivencia , Taquicardia/complicaciones , Taquicardia/etiologíaRESUMEN
We propose a design adjustment to the high foot laser pulse [T. R. Dittrich et al., Phys. Rev. Lett. 112, 055002 (2014)] that is predicted to lower the fuel adiabat, increase compression and neutron production, but maintain similar ablation front growth. This is accomplished by lowering the laser power between the first and the second pulses (the "trough") so that the first shock remains strong initially but decays as it transits the ablator and enters the capsule fuel in a process similar to direct-drive "adiabat shaping" [S. E. Bodner et al., Phys. Plasmas 7, 2298 (2000)]. Integrated hohlraum simulations show that hohlraum cooling is sufficient to launch decaying shocks with adequate symmetry control, suggesting that adiabat shaping may be possible with indirect-drive implosions. Initial experiments show the efficacy of this technique.
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OBJECTIVE: To provide the first data which evaluates an HIV risk reduction intervention designed to reduce HIV high-risk sexual behavior in African-American homosexual and bisexual men. SUBJECTS: Participants (n = 318) were recruited from bars, bathhouses, and erotic bookstores, and through homosexual African-American organizations, street out-reach, media advertisements, and personal referrals of individuals aware of the study. METHODS: Participants were randomized into a single or triple session experimental group or a wait-list control group. Both experimental interventions included AIDS risk education, cognitive-behavioral self-management training, assertion training, and attempts to develop self-identity and social support. Data collection involved assessments of self-reported changes in sexual behavior at 12- and 18-month follow-up. RESULTS: Participants in the triple session intervention greatly reduced their frequency of unprotected anal intercourse (from 46 to 20%) at the 12-month follow-up evaluation and (from 45% to 20%) at the 18-month follow-up evaluation. However, levels of risky behavior for the control group remained constant (from 26 to 23% and from 24 to 18%) at 12- and 18-month follow-up evaluations, respectively. In addition, levels of risky behavior for the single session intervention decreased only slightly (from 47 to 38% and from 50 to 38%) at the 12- and 18-month follow-up evaluations, respectively. CONCLUSIONS: Results were interpreted to demonstrate the superiority of a triple session over a single session intervention in reducing risky sexual behavior in this cohort.
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Bisexualidad , Negro o Afroamericano , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Adulto , Estudios de Evaluación como Asunto , Humanos , Entrevistas como Asunto , Masculino , Factores de RiesgoRESUMEN
Circulating N-terminal PTH-related protein (PTHrP), N-terminal PTH, and 1,25-dihydroxyvitamin D [1,25-(OH)2D] concentrations were measured in normal dogs and dogs with cancer-associated hypercalcemia (CAH), parathyroid adenomas, and miscellaneous tumors. PTHrP was undetectable (less than 1.8 pM) in normal dogs and increased in dogs with CAH due to adenocarcinomas derived from apocrine glands of the anal sac (44.9 +/- 27 pM), lymphoma (8.3 +/- 4.4 pM), and miscellaneous carcinomas (13.3 +/- 11.4 pM). The PTHrP concentration decreased in dogs with lymphoma and anal sac adenocarcinomas after successful treatment of CAH. The PTHrP concentration had a significant linear correlation with total serum calcium in dogs with anal sac adenocarcinomas and hypercalcemia, but not in dogs with lymphoma and hypercalcemia. Serum N-terminal PTH concentrations were usually in the normal range (12-34 pg/ml) for all groups of dogs except dogs with parathyroid adenomas (83 +/- 38 pg/ml). The serum PTH concentration increased after successful treatment of CAH. Serum 1,25-(OH)2D concentrations were decreased, normal, or increased in dogs with CAH, and 1,25-(OH)2D levels decreased after treatment of CAH. In summary, circulating concentrations of PTHrP are consistently increased in dogs with CAH, and PTHrP appears to play an important role in the induction of hypercalcemia.
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Adenoma/veterinaria , Calcitriol/sangre , Enfermedades de los Perros , Hipercalcemia/veterinaria , Neoplasias/veterinaria , Hormona Paratiroidea/sangre , Neoplasias de las Paratiroides/veterinaria , Proteínas/análisis , Adenoma/fisiopatología , Animales , Calcio/sangre , Perros , Hipercalcemia/sangre , Hipercalcemia/etiología , Neoplasias/fisiopatología , Neoplasias/terapia , Proteína Relacionada con la Hormona Paratiroidea , Neoplasias de las Paratiroides/fisiopatología , Valores de Referencia , Análisis de RegresiónRESUMEN
This study compared the performance of three self-rating mania scales, The Internal State Scale (ISS), the Self-Report Manic Inventory (SRMI), and the Altman Self-Rating Mania Scale (ASRM), in a group of patients with acute mania. Forty-four adult inpatients with bipolar disorder, manic or mixed, completed all scales shortly after admission, and 31 patients completed them again after 4-6 weeks of pharmacotherapy. Patients also were rated by clinicians on the Clinician-Administered Rating Scale for Mania (CARS-M). At baseline, scores on the ASRM and the ISS well-being subscale were significantly correlated with CARS-M scores. Posttreatment scores were significantly decreased for the ASRM, SRMI, and the ISS activation subscale. The sensitivities for each scale to correctly identify patients with acute symptoms was 45% for the ISS, 86% for the SRMI, and 93% for the ASRM. Specificities were 73%, 46.6%, and 33%, respectively. The ASRM and SRMI were more sensitive than the ISS in screening patients with acute mania. All three measures were sensitive to treatment effects; however, the item content of the SRMI and the poor sensitivity of the ISS may limit their utility in inpatient settings.
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Trastorno Bipolar/diagnóstico , Autoevaluación (Psicología) , Encuestas y Cuestionarios , Enfermedad Aguda , Adulto , Femenino , Humanos , Masculino , Sensibilidad y EspecificidadRESUMEN
We report on the development, reliability, and validity of the Altman Self-Rating Mania Scale (ASRM). The ASRM was completed during medication washout and after treatment by 22 schizophrenic, 13 schizoaffective, 36 depressed, and 34 manic patients. The Clinician-Administered Rating Scale for Mania (CARS-M) and Mania Rating Scale (MRS) were completed at the same time to measure concurrent validity. Test-retest reliability was assessed separately on 20 depressed and 10 manic patients who completed the ASRM twice during washout. Principal components analysis of ASRM items revealed three factors: mania, psychotic symptoms, and irritability. Baseline mania subscale scores were significantly higher for manic patients compared to all other diagnostic groups. Manic patients had significantly decreased posttreatment scores for all three subscales. ASRM mania subscale scores were significantly correlated with MRS total scores (r = .718) and CARS-M mania subscale scores (r = .766). Test-retest reliability for the ASRM was significant for all three subscales. Significant differences in severity levels were found for some symptoms between patient ratings on the ASRM and clinician ratings on the CARS-M. Mania subscale scores of greater than 5 on the ASRM resulted in values of 85.5% for sensitivity and 87.3% for specificity. Advantages of the ASRM over other self-rating mania scales are discussed.
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Trastorno Bipolar/diagnóstico , Escalas de Valoración Psiquiátrica , Adulto , Trastorno Depresivo/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Índice de Severidad de la EnfermedadRESUMEN
There are currently seven rating scales available to assess manic symptomatology. All, however, have some limitations that could restrict their clinical and research utility. To resolve these deficiencies the Clinician-Administered Rating Scale for Mania (CARS-M) was developed and normed on 96 patients with mixed diagnoses during baseline and following treatment. Interrater reliability was established across multiple raters viewing 14 videotaped interviews and comparing agreement among individual items and total scores. Test-retest reliability was assessed on 36 patients twice during baseline. The mean intraclass correlation coefficient among five raters across items for each of the 14 patients was 0.81, and for total scores 0.93. Principal components analysis of items revealed two factors: mania, and psychosis. Test-retest reliability was significant for both factors (range = 0.78 to 0.95). Internal validity, comparing each item with its respective total factor score, revealed significant correlations for all items. Correlation of CARS-M total scores with mania rating scale (MRS) total scores was 0.94. Results indicate the CARS-M is both a reliable and valid measure of the severity of manic symptomatology, which incorporates a number of methodological improvements leading to greater precision and clinical utility.
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Trastorno Bipolar/diagnóstico , Determinación de la Personalidad/estadística & datos numéricos , Adolescente , Adulto , Trastorno Bipolar/psicología , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Psicometría , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Psicología del EsquizofrénicoRESUMEN
Qualitative data from individual interviews with 18-29 year old African American men, who have sex with men (n = 76) were used to examine the relationship of negative attitudes toward homosexuality, self-esteem, and risk for HIV. Respondents perceived members of their communities as holding negative attitudes toward homosexuality, and many thought the African American community was less accepting of homosexuality than the white community. There was evidence that these negative attitudes are internalized by some of the young African American men themselves. Respondents mentioned several ways that negative attitudes toward homosexuality could lead to lower self-esteem and psychological distress in young gay and bisexual men. In addition, respondents articulated several mechanisms by which low self-esteem and psychological distress might be associated with sexual behaviors that put one at risk for HIV. We concluded that addressing and changing society's negative views of homosexuality are important components of a comprehensive approach to reducing the transmission of HIV, especially among young people in communities of color.
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Síndrome de Inmunodeficiencia Adquirida/transmisión , Negro o Afroamericano , Homosexualidad Masculina , Prejuicio , Autoimagen , Adulto , Chicago , Georgia , Humanos , Masculino , Religión y Sexo , Factores de RiesgoRESUMEN
Help-seeking for AIDS high-risk sexual behavior and its association with HIV status were examined among 318 gay and bisexual men in the San Francisco Bay Area who participated in the African American Men's Health Project, a longitudinal survey of gay and bisexual African-American men. A third (36%) of the sample reported seeking help regarding their concerns about HIV high-risk sexual behavior. Peers and professionals were the most widely sought sources of help and the sources perceived to be the most helpful. Men (39%) who had received the HIV antibody test and who were HIV seropositive were more likely to seek help than men who were HIV seronegative or did not know their HIV status (25%). Furthermore, gay men who were HIV seropositive or who knew their serostatus were more likely to seek help from professionals and peers. Explanations for the differences in help-seeking by HIV-seropositive men are discussed with implications for the development of social support for HIV risk reduction among gay and bisexual African-American men.
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Síndrome de Inmunodeficiencia Adquirida/prevención & control , Bisexualidad , Negro o Afroamericano/psicología , Homosexualidad Masculina , Aceptación de la Atención de Salud , Conducta Sexual , Síndrome de Inmunodeficiencia Adquirida/psicología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Adolescente , Adulto , Bisexualidad/psicología , Seronegatividad para VIH , Seropositividad para VIH/psicología , Seropositividad para VIH/transmisión , Conocimientos, Actitudes y Práctica en Salud , Homosexualidad Masculina/psicología , Humanos , Estudios Longitudinales , Masculino , Grupo Paritario , Factores de Riesgo , San Francisco , Medio Social , Apoyo SocialRESUMEN
Data from 76 qualitative interviews with 18- to 29-year-old African American men who have sex with men (MSM) in Chicago and Atlanta were examined to identify perceptions of "community" and components of a community-level HIV/AIDS intervention. Many men reported feeling marginal to African American and gay White communities because of perceived homophobia and racism. Those who reported feeling part of gay African American communities characterized communities in terms of settings, social structures, and functions, including social support, socialization, and mobility. Despite these positive functions, divisions among groups of MSM, lack of settings for nonsexual interaction with other MSM, lack of leadership, and negative attitudes toward homosexuality may make it difficult for men to participate in activities to alter community contexts that influence behavior. Rather, changing norms, increasing social support, and community building should be part of initial community-level interventions. Community building might identify leaders, create new settings, and create opportunities for dialogue between MSM and African American community groups to address negative perceptions of homosexuality.
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Actitud Frente a la Salud , Negro o Afroamericano/psicología , Servicios de Salud Comunitaria/organización & administración , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Evaluación de Necesidades/organización & administración , Adolescente , Adulto , Negro o Afroamericano/educación , Chicago , Redes Comunitarias , Georgia , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Prejuicio , Identificación Social , Encuestas y Cuestionarios , Población UrbanaRESUMEN
The susceptibility of six indigenous macroinvertebrate species representative of U.S. Pacific Northwest streams (Ameletus sp., Brachycentrus americanus, Calineuria californica, Cinygma sp., Lepidostoma unicolor, Psychoglypha sp. early and late instar) to formulated triclopyr ester (herbicide) and carbaryl (insecticide) was determined using laboratory bioassays. Acute toxicity was expressed as the lethal concentration to 50% (LC50) and 1% (LC1) of the test population based on a 96-h exposure duration. Carbaryl was found to be 1,000 times more toxic than triclopyr for all the organisms tested. The LCI values (7.5, 28.8, 9.0, 3.0, 9.5, 14.8, 33.8 microg/L, respectively, for carbaryl and 1.8, 3.9, 4.0, 4.2, 29.0, 16.1 mg/L, respectively, for triclopyr) were used in the calculation of hazardous concentration to 5% of the stream macroinvertebrate community (HC5) based on the lower 95% confidence limit (HC5/95). The hazardous concentration (HC5/95) for triclopyr was 0.11 mg/L and for carbaryl ranged from 0.43 to 0.66 microg/L, respectively. Triclopyr and carbaryl symptomology were analyzed for two organisms, C. californica and Cinygma sp. Carbaryl symptomology included knockdown and moribund states with severity and time of appearance being a function of dose. In triclopyr poisoning, death occurred suddenly with little or no symptomology. Time to 50% mortality (LT50) values were consistently higher for C. californica than for Cinygma sp. exposed to both chemicals at similar concentrations.