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It is suggested that in addition to seismicity deep fluid injection may cause surface uplift and subsidence in oil and gas-producing regions. This study uses the Raton Basin as an example to investigate the hydromechanical processes of surface uplift and subsidence during wastewater injection. The Raton Basin, in southern central Colorado and northern central New Mexico, has experienced wastewater injection related to coalbed methane and gas production starting in 1994. In this study, we estimate the extent and magnitude of total vertical deformation in the Raton Basin from 1994 to 2020 and incremental deformation between the years 2017 to 2020. Results indicate a modeled uplift as much as 15 cm occurring between 1994 and 2020. Between 2017 and 2020, up to 3 cm of uplift occurred, largely near the northwestern injection wells. Most modeled uplift between 1994 and 2020 occurred near the southern wells, where the greatest cumulative volume of wastewater was injected. However, modeled subsidence occurred around the southern and eastern wells between 2017 and 2020, after the rate of injection decreased. Modeling indicates that while the magnitude of modeled uplift corresponds to cumulative injection volume and maximum rate in the long-term, short-term incremental deformation (uplift or subsidence) is controlled by changes in the rate of injection. The number of yearly earthquake events follows periods of rapid modeled uplifting throughout the Basin, suggesting that measurable surface deformation may be caused by the same injection-induced pore pressure perturbations that initiate seismicity.
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Terremotos , Água Subterrânea , Colorado , New Mexico , Modelos Teóricos , Águas Residuárias , Campos de Petróleo e GásRESUMO
2,2'-Bis(4-dimethylaminophenyl)- and 2,2'-dicyclohexyl-1,1',3,3'-tetramethyl-2,2',3,3'-tetrahydro-2,2'-bibenzo[d]imidazole ((N-DMBI)2 and (Cyc-DMBI)2) are quite strong reductants with effective potentials of ca. -2 V vs ferrocenium/ferrocene, yet are relatively stable to air due to the coupling of redox and bond-breaking processes. Here, we examine their use in accomplishing electron transfer-induced bond-cleavage reactions, specifically dehalogenations. The dimers reduce halides that have reduction potentials less cathodic than ca. -2 V vs ferrocenium/ferrocene, especially under UV photoexcitation (using a 365 nm LED). In the case of benzyl halides, the products are bibenzyl derivatives, whereas aryl halides are reduced to the corresponding arenes. The potentials of the halides that can be reduced in this way, quantum-chemical calculations, and steady-state and transient absorption spectroscopy suggest that UV irradiation accelerates the reactions via cleavage of the dimers to the corresponding radical monomers.
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The pervasive nature of plastic and the longevity of plastics leaves a legacy of microplastics (MPs) that contaminate our environment, including drinking water sources. Although MPs have been documented in every environmental setting, a paucity of research has focused on the transport and fate of MPs in groundwater. Previous field and laboratory studies have shown that MPs can migrate through aquifer material and are influenced by environmental factors. This study used controlled column experiments to investigate the influence of polymer type (polyamide, polyethylene, polypropylene, and polyester) and particle shape (fragment, fiber, and sphere) on MP retardation and retention. The results showed that all individual MP types investigated were retarded compared to the NaCl tracer, with a retardation factor ranging from 1.53 to 1.75. While hypothesized that presence of multiple types and shapes could change mobility, the results indicate that this hypothesis is not correct for the conditions tested. This study provides new insights into MP transport in groundwater systems based on the characteristics of MP particles. In addition, this study demonstrates the need for further research on types of MPs and under more conditions, especially in the presence of a mixture of types and shapes of MPs to gauge what is occurring in natural systems where many MPs are present together.
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A simple relation between pore pressure change and one-dimensional surface deformation is presented. The relation is for pore pressure change in a confined aquifer that causes surface deformation. It can be applied to groundwater models of any discretization and is computationally efficient. The estimated surface deformation from model results can be compared to observed surface deformation through geodetic techniques such as Differential Interferometric Synthetic Aperture Radar. Model parameters then are constrained using the observed surface deformation. The validity of this relation is shown through constraint of model parameters for surface uplift due to pore pressure increase caused by wastewater disposal injection.
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Purpose: To explore the relationship between medical mistrust, as measured by the Group-Based Medical Mistrust (GBMM) scale, and HIV care adherence among a cohort of minority women receiving care in a U.S. safety net clinic. Methods: English-, Spanish-, and Haitian Creole (Creole)-speaking patients with a recent history of nonadherence to care were surveyed. Results: English speakers endorsed the highest level of mistrust, followed by Spanish speakers and Creole speakers. Creole speakers endorsed lower mistrust, lower suspicion of providers, and lower levels of "perceived health care disparities." Higher mistrust was associated significantly with lower medication adherence, and lower rates of viral suppression (nonsignificant). Conclusion: Understanding perceptions of medical care and the relationship to HIV care adherence is an important step to addressing negative health outcomes for ethnic minority women with HIV. Clinical Trial Registration Number: NCT03738410.
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Background: Ending HIV/AIDS in the United States requires tailored interventions. This study is part of a larger investigation to design mCARES, a mobile technology-based, adherence intervention for ethnic minority women with HIV (MWH). Objective: To understand barriers and facilitators of care adherence (treatment and appointment) for ethnic MWH; examine the relationship between these factors across three ethnic groups; and, explore the role of mobile technologies in care adherence. Methods: Cross-sectional, mixed-methods data were collected from a cohort of African-American, Hispanic-American and Haitian-American participants. Qualitative data were collected through a focus group (n = 8) to assess barriers and facilitators to care adherence. Quantitative data (n = 48) surveyed women on depressive symptomology (PHQ-9), HIV-related stigma (HSS) and resiliency (CD-RISC25). We examined the relationships between these factors and adherence to treatment and care and across groups. Findings: Qualitative analyses revealed that barriers to treatment and appointment adherence were caregiver-related stressors (25%) and structural issues (25%); routinization (30%) and religion/spirituality (30%) promoted adherence to treatment and care. Caregiver role was both a hindrance (25%) and promoter (20%) of adherence to treatment and appointments. Quantitatively, HIV-related stigma differed by ethnic group; Haitian-Americans endorsed the highest levels while African-Americans endorsed the lowest. Depression correlated to stigma (R = 0.534; p < 0.001) and resiliency (R = -0.486; p < 0.001). Across ethnic groups, higher depressive symptomology and stigma were related to viral non-suppression (p < 0.05)-a treatment adherence marker; higher resiliency was related to viral suppression. Among Hispanic-Americans, viral non-suppression was related to depression (p < 0.05), and among African-Americans, viral suppression was related to increased resiliency (p < 0.04). Conclusion: Multiple interrelated barriers to adherence were identified. These findings on ethnic group-specific differences underscore the importance of implementing culturally-competent interventions. While privacy and confidentiality were of concern, participants suggested additional intervention features and endorsed the use of mCARES as a strategy to improve adherence to treatment and appointments.
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Etnicidade , Infecções por HIV , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Haiti , Humanos , Adesão à Medicação , Grupos Minoritários , Estados Unidos/epidemiologiaRESUMO
Intravaginal practices (IVP) are linked to bacterial vaginosis (BV), obstetric/gynecological complications, and HIV. Late adolescent and young adult (LAYA) women in Zambia have high rates of HIV. Adult and mature (AM) HIV-infected women in Zambia engage in IVP for hygiene, health, and sexuality reasons; however, to our knowledge, IVP use among LAYA women has not been examined. This study compares IVP use between LAYA and AM women to identify age-specific factors to target when developing IVP reduction interventions for LAYA women. LAYA (≤25 years; n = 24) and AM (>25 years; n=124) HIV-infected women completed self-administered demographic, HIV history, sexual risk factor, and IVP measures. LAYA and AM women were then compared. Number of sexual partners, sexual activity, or condom use did not differ between groups. Rates of IVP in the prior month with different products were similar, though LAYA women used soap more frequently (96% versus 74.2%, p = 0.034). LAYA women were more likely to use products for hygiene reasons (soap 83% versus 43%; cloth, paper, or wipes 50% versus 17%, p < 0.05); and AM women to use products to please sexual partners (cloth 20% versus 56%, p = 0.074). Interventions tailored to LAYA women may be needed to reduce IVP and subsequent BV as LAYA women may have different reasons for engaging in IVP, in comparison with AM women. Reduced IVP among LAYA women may decrease the risk for HIV transmission to sexual partners and newborns and is urgently needed in settings with high prevalence of IVP, BV, and HIV infections, such as Zambia.
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Infecções por HIV/complicações , Ducha Vaginal/efeitos adversos , Vaginose Bacteriana/epidemiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Humanos , Ducha Vaginal/psicologia , Adulto Jovem , Zâmbia/epidemiologiaRESUMO
High levels of inflammatory cytokines in the genital tract suggest mucosal vulnerability and increased risk of HIV and sexually transmitted infection (STI) acquisition. Intravaginal douching is associated with bacterial vaginosis (BV) in women in the United States, and both douching and BV are linked to HIV and STI acquisition. This study evaluates inflammatory cytokines in the genital tract to increase understanding of the effects of both BV and intravaginal douching to the vaginal mucosa. A cross-sectional study of participants in the Miami WIHS investigated 72 reproductive age women (45 HIV+ and 27 high-risk HIV-) who completed intravaginal douching questionnaires and underwent collection of vaginal swabs and cervicovaginal lavages (CVLs). BV was assessed using the Nugent score. Inflammatory cytokines in the CVLs (interleukin [IL]-6, IL-8, IL-1α, IL-1ß, soluble intracellular adhesion molecule-1 [sICAM-1], interferon [IFN]α2, chemokine C ligand 5 (CCL5), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP1), tumor necrosis factor alpha (TNFα), and secretory leukocyte protease inhibitor [SLPI]) were measured. Fourteen (19%) women reported intravaginal douching; 24 (33%) had BV. BV, intravaginal douching, and HIV were associated with higher levels of inflammatory cytokines. After controlling for demographic and risk factors and HIV status, women who had BV and douched had higher levels of inflammatory cytokines than those without BV and who did not douche, or who only had BV or only douched. These findings suggest that BV and douching are associated with greater mucosal inflammation and may facilitate HIV acquisition and transmission. Although longitudinal studies are needed to determine temporal associations and causality, interventions to decrease rates of intravaginal douching and BV could significantly decrease women's risks of acquiring STIs and HIV and limit the spread of HIV.