Network Analysis of Organizations Providing HIV Services in Chicago: Toward an Integrated Response to the HIV Epidemic.

CONTEXT: The public health response to the HIV epidemic has increasingly centered on the uptake of and adherence to biomedical interventions (eg, pre-exposure prophylaxis [PrEP], treatment as prevention [TasP]). Traditionally, various community and health care organizations have worked to address different stages of PrEP or TasP care. OBJECTIVE: To understand the importance of how HIV prevention organizations providing these services interact to provide the comprehensive care needed for successful HIV and PrEP continuum outcomes. DESIGN: Utilizing an Organizational Network Survey, network ties were examined between formal and informal partnerships among community agencies. SETTING: This study examined community agencies in the current HIV prevention system in Chicago. PARTICIPANTS: Seventy-two community agencies across the Chicago metropolitan area. MAIN OUTCOME MEASURES: Using network analysis, this study examined ties between community agencies and assessed perceptions of collaboration and competitiveness in the current HIV prevention system in Chicago. RESULTS: Overall, respondents reported that the current environment of HIV prevention in Chicago was extremely (18.8%), moderately (37.5%), or somewhat collaborative (37.5%) and extremely (68.8%) or moderately competitive (25.0%). The majority of partnerships reported were informal, with less than a quarter being formalized. That said, those who reported formal partnerships reported being satisfied with those relationships. There was a significantly negative association between density and perceived collaboration-grantees experiencing a more collaborative also reported less dense networks. CONCLUSION: These findings indicate that, despite perceived competitiveness, agencies are willing to work together and create a cohesive HIV prevention and treatment system. However, more work should be done to foster an environment that can support the formation of partnerships, to improve a coordinated response to providing HIV care, and sustain mutually beneficial relationships.

Factors Associated with PrEP Support and Disclosure Among YMSM and Transgender Individuals Assigned Male at Birth in Chicago.

Pre-exposure prophylaxis (PrEP) is one of the best biomedical HIV prevention tools available. However, uptake, particularly in communities of men who have sex with men (MSM) and transgender individuals assigned male at birth (AMAB), remains low. Further, the role of an individual's social support structure on PrEP uptake and adherence remains largely understudied. Understanding MSM and AMAB transgender individuals' perceptions of PrEP use as well as support and patterns of disclosure of (or intent to disclose) their PrEP status may offer key insights into how best to improve uptake in vulnerable communities. Further, the influence of one's social connections on other factors, such as perceptions of and conversations about PrEP deserves attention as well, as these factors may be key to improved knowledge and uptake. Therefore, we assessed perceptions of PrEP use, disclosure of or intent to disclose PrEP status, and social support and associated factors among a cohort of MSM and AMAB transgender individuals in a large Midwestern city. Results demonstrated that, among those not taking PrEP, bisexual participants and those unsure of their sexual identity were less likely to be comfortable with the idea of disclosing PrEP use were they ever to start taking it. Encouragingly however, we found that individuals who reported disclosing their PrEP status had high rates of support among friends and relatives. We also observed that knowing someone else who was on PrEP was associated with increased likelihood of discussing PrEP with one's medical provider, as was increased age. Other findings and implications for research, policy, and practice are discussed within.

Development and characterisation of a silicon PIN diode array based highly sensitive portable continuous radon monitor.

This paper discusses the development and characterisation of a portable and highly sensitive continuous radon monitor (CRM) based on an array of in-house developed silicon PIN diode detectors. The development of this system was initiated in view of the limitations of the available similar radon measurement systems with regards to low sensitivity. The system utilises a hemispherical metal chamber (1 L capacity) for active air sampling. A quantitative estimation of radon concentration is carried out through alpha spectroscopy of electro-deposited (222)Rn decay products on the detector surface. The system was successfully tested and characterised in laboratory conditions. The characterisation experiments included optimisation of sensitivity, calibration with respect to linearity and a study of the influence of humidity on its performance. The novel PIN diode array design yields a high sensitivity of 1.76 ± 0.003 counts h(-1)/(Bq m(-3)) at a relative humidity level of 10% in the sampled air, which is more than two times as high as that reported for similar commercial systems. This instrument displayed a minimum detectable activity level of 0.80 Bq m(-3).

PrEP4Love: The Role of Messaging and Prevention Advocacy in PrEP Attitudes, Perceptions, and Uptake Among YMSM and Transgender Women.

BACKGROUND: Despite high efficacy, use of pre-exposure prophylaxis (PrEP) remains low among young men who have sex with men (MSM) and transgender women (TW), primarily because of barriers such as stigma and resource awareness. We evaluated a social marketing campaign known as PrEP4Love that works to eliminate PrEP stigma; and awareness gaps through targeted advertising. SETTING: Chicago, Illinois. METHODS: Participants were enrolled within a cohort study of young MSM and TW (RADAR). Data were collected between June 2017 and April 2018 from HIV-negative individuals attending a follow-up visit. Surveys assessed demographics, PrEP attitudes and perceptions, and PrEP4Love campaign awareness. Associations between PrEP4Love awareness and PrEP perceptions, uptake, and behaviors were assessed using multiple logistic regression controlling for age, race/ethnicity, gender, sexual identity, and ever having used PrEP. RESULTS: Of 700 participants, the majority (75.9%) indicated seeing PrEP4Love ads in Chicago. Those who had seen ads were more likely to be out to their providers (odds ratio = 1.95; 95% confidence interval: 1.17 to 3.23) than those who had not, and those who had conversations were significantly more likely to have initiated the conversation themselves. Individuals who had seen ads were more likely to have taken PrEP in the last 6 months (odds ratio = 1.87; 95% confidence interval: 1.15 to 3.16) and more likely to believe their friends and the general public approved of and used PrEP. CONCLUSION: Social marketing campaigns are promising interventions that have the potential to alleviate barriers to HIV prevention, particularly among MSM and TW. Future research should evaluate the impact of these initiatives at multiple time points.

Geospatial perspectives on health: The PrEP4Love campaign and the role of local context in health promotion messaging.

Pre-exposure prophylaxis (PrEP) remains one of the most effective biomedical interventions for the prevention of HIV transmission. However, uptake among populations most impacted by the HIV epidemic remains low. La rge-scale awareness and mobilization campaigns have sought to address gaps in knowledge and motivation in order to improve PrEP diffusion. Such campaigns must be cognizant of the historical, physical, and structural contexts in which they exist. In urban contexts, neighborhood segregation has the potential to impact health outcomes and amplify disparities. Therefore, we present novel geospatial approaches to the evaluation of a Chicago-based PrEP messaging campaign (PrEP4Love) in a 2018 cohort of men who have sex with men and transgender women, contextualizing results within the localized infrastructure and public health landscape, and examining associations between geographic location and campaign efficacy. Results revealed notable variance in rates of PrEP uptake associated with campaign exposure by Chicago planning area, which are likely explained by the historical and contemporary impacts of racist structures on physical environment and city infrastructure. Findings have important implications for the evaluation and implementation of future messaging campaigns, which should take the unique historical, structural, and geospatial factors of their particular settings into account in order to achieve maximum impact.

Lyoluminescence and ESR correlation studies of trehalose dihydrate.

ESR studies of irradiated lyoluminescence (LL) phosphor, trehalose dihydrate showed a linear free radical growth up to a dose of 11 kGy. The LL output measured under oxygen equilibrated conditions showed an extension of the dosimetric response from 0.6 to 6 kGy. ESR spectral analysis indicates the formation of two radical species viz., 'a' and 'b' and their involvement in the LL process. The estimated free radical concentrations of radicals 'a' and 'b' were found to be 6.81 x 10(15) and 1.35 x 10(16) g(-1), respectively, for a gamma dose of 10.8 kGy.

Assessment of calibration parameters for an aerial gamma spectrometry system using Monte-Carlo technique.

During a radiation emergency subsequent to a nuclear accident or weapon fallout, quick assessment of the ground contamination and the resulting exposure is of prime importance in planning and execution of effective counter measures. For an online assessment of ground contamination, it is essential to calibrate the detector system for several parameters viz. the source energy, source deployment matrix, the flight altitude and position above the contaminated surface. This article discusses the methodology to predict all the necessary parameters like photon fluence at various altitudes, the photo-peak counts in different energy windows, Air to Ground Correlation Factors IAGCF) and the dose rate at any height due to air scattered gamma ray photons. The methodology includes generation of theoretically simulated gamma spectra at a required detector position for a given source distribution on the ground using Monte-Carlo method provided by general purpose coupled neutron/photon transport code (MCNP CCC-200). Thus generated gamma spectra are analyzed to arrive at the required parameters mentioned above.