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1.
Heliyon ; 10(12): e32491, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38952357

RESUMO

Purpose: To investigate the physical properties of commercially available multipurpose soft contact lens solutions in Ghana. Methods: pH (Kelilong ICL-099 pH meter, China), osmolality (OSMOMAT 3000, GONOTEC, Germany), surface tension (Sigma 700 Tensiometer, Sweden), and viscosity (CFOC-200 Viscometer, Cannon Company, USA) of various soft contact lens multipurpose solutions (MPS) were measured in triplicates at room temperature. Viscosity measurements were also taken at 34 °C ocular surface temperature. The solutions examined were Opti-Free Replenish (OFR), Trufresh (TF), Avizor (AV), Freshlook (FL), and Refresh (RF). Results: Several solutions were largely hypo-osmotic in the range of 108-231 mOsm/kg, the exception being Avizor, which had osmolality values that were closer to human tears (301 ± 0.58 mOsm/kg). The range of pH values of the solutions (6.33-8.24, mean (SD) = 7.53 ± 0.18) fell within the reported tolerable range for the ocular surface (6.20-9.00). Surface tension values ranged from 35.86 to 42.27 mNm with a mean of 38.49 ± 2.32 mNm. The average viscosity of most solutions at room temperature (25 °C) was 1.44 ± 0.49 cP with a range of 1.04-2.15 cP. Significantly lower values ranging from 0.79 to 1.58 cP were obtained at ocular surface temperature (34 °C), p = 0.0001). Conclusions: The physical properties of many of the solutions used as MPS in Ghana are markedly variable. Nevertheless, pH, surface tension, and viscosity fall within the acceptable limits of ocular physiological tolerance; except for osmolality, which majority were outside the reported tolerable range for the ocular surface. This information may partly explain the reason some patients exhibit strong preferences for certain care systems and should aid clinical decision-making when prescribing eye care systems to patients.

2.
Contemp Clin Trials Commun ; 40: 101314, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38994348

RESUMO

Background: Posttraumatic Stress Disorder (PTSD) impacts both individual and relational functioning. Veteran couples are at increased risk of relationship distress due to military stressors such as deployment, family reintegration, and traumatic stress. Although both Cognitive-Behavioral Conjoint Therapy (CBCT) and its brief version (bCBCT) consistently have large effects on reducing PTSD symptoms, these treatments have more variable effects on relational outcomes. Given the impact of relationship functioning on the overall health of veterans, improving the effect of PTSD treatments on relationship functioning is an essential area of research. One promising path is the role of MDMA (3,4-methylenedioxymethamphetamine)-assisted therapy in augmenting the relational impact of established therapeutic interventions such as bCBCT. Method/Design: This is a single site, open-label study assessing the preliminary efficacy, safety, and acceptability of MDMA-assisted therapy in combination with bCBCT in 8 veterans with PTSD and their intimate partners (N = 16). Therapy teams trained in bCBCT and MDMA-assisted therapy will deliver bCBCT combined with two MDMA sessions and two couple emotion focused integration sessions. PTSD symptom severity and relationship functioning outcomes will be evaluated. Conclusion: This is the first study to examine the efficacy of MDMA-assisted bCBCT for improving PTSD and relationship functioning among a sample of U.S. military veterans and their partners. This project could provide an opportunity to pilot a scalable model of treating PTSD within the Veterans Affairs healthcare system and leverage the benefits of MDMA for veterans with PTSD, as well as the downstream benefits to their partner on both individual and relationship functioning. ClinicalTrials.gov Identifier: NCT05979844.

3.
Phys Rev Lett ; 131(4): 041003, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566859

RESUMO

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03) ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3) events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47} cm^{2} for a WIMP mass of 28 GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

4.
Eur Phys J C Part Fields ; 83(8): 717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576939

RESUMO

The DARWIN observatory is a proposed next-generation experiment with 40 tonnes of liquid xenon as an active target in a time projection chamber. To study challenges related to the construction and operation of a multi-tonne scale detector, we have designed and constructed a vertical, full-scale demonstrator for the DARWIN experiment at the University of Zurich. Here, we present the first results from a several-months run with 343kg of xenon and electron drift lifetime and transport measurements with a 53cm tall purity monitor immersed in the cryogenic liquid. After 88days of continuous purification, the electron lifetime reached a value of (664±23)µs. We measured the drift velocity of electrons for electric fields in the range (25-75) V/cm, and found values consistent with previous measurements. We also calculated the longitudinal diffusion constant of the electron cloud in the same field range, and compared with previous data, as well as with predictions from an empirical model.

5.
Phys Rev Lett ; 130(26): 261002, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450817

RESUMO

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17} GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

6.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306777

RESUMO

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

7.
Eur Phys J C Part Fields ; 82(7): 599, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35821975

RESUMO

The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and 222 Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background ( ∼ 17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected 222 Rn activity concentration in XENONnT is determined to be 4.2 ( - 0.7 + 0.5 )  µ Bq/kg, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system.

8.
AIDS Care ; 27(7): 870-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25650646

RESUMO

Women in their reproductive years make up about 50% of all HIV-positive persons globally. These women, just as their HIV-negative counterparts, wield the right to procreate. However, HIV infection and lack of appropriate information on reproductive options may negatively impact women's procreative decision-making. This study assessed fertility intentions of HIV-positive women receiving antiretroviral therapy (ART) in southern Ghana. Quantitative methods were used to collect data from HIV-positive women receiving ART at four treatment centers. HIV-positive aged 18-49 years, and receiving ART were selected using systematic random sampling technique. Three hundred eighteen women were interviewed after informed consent. We used univariate analysis to generate descriptive tabulations for key variables. Bivariate analysis and logistic regression modeling respectively produced unadjusted and adjusted associations between background attributes of respondents and their childbearing decision-making. All analyses were performed using IBM SPSS Statistics for Windows, Version 20.0. Irrespective of age, reproductive history, and duration of HIV diagnosis, 46% of the women were desirous of procreating. The bivariate level analysis shows that women in their late reproductive ages (30-39 years) had the strongest desire to procreate (p < 0.001). After controlling for a number of covariates, primiparous and secundiparious women were about twice as likely to desire children (aOR = 2.553; 95% CI 1.480-4.401), and so were women aged 30-39 years (aOR = 2.149; 95% CI 1.202-3.843). Of 54% women who do not wish to procreate, achievement of desired family size (64.3%) was more popular a reason than fear of vertical transmission of HIV (7.5%), poor health status (5%), and pregnancy-related complications (1.6%).


Assuntos
Fármacos Anti-HIV/uso terapêutico , Serviços de Planejamento Familiar/estatística & dados numéricos , Soropositividade para HIV/psicologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Comportamento Sexual/psicologia , Adolescente , Adulto , Estudos Transversais , Tomada de Decisões , Escolaridade , Feminino , Gana/epidemiologia , Soropositividade para HIV/transmissão , Humanos , Intenção , Motivação , Gravidez
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