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1.
Philos Trans A Math Phys Eng Sci ; 382(2275): 20230124, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38910456

RESUMO

Elucidating the role of strange baryons (hyperons) in neutron stars requires detailed knowledge of hyperon-nucleon interactions in the light (u,d,s) quark sector. The structure of the hyperons and their excitation spectra also directly impact, and are an input to, models of big-bang nucleosynthesis. The upcoming K-long Facility will provide a much-needed intense and clean neutral strange meson beam, from which hyperons can be produced at rates where hyperon structure, hyperon-nucleon interactions and higher-order interactions can be studied with a new level of accuracy and for hitherto unreachable measurements. The new facility has the potential to address long-standing questions surrounding the strange sector of the strong force and its relevance to the structure of atomic nuclei, neutron stars and the cosmos at large. This article is part of the theme issue 'The liminal position of Nuclear Physics: from hadrons to neutron stars'.

2.
Pharmacoepidemiol Drug Saf ; 33(6): e5801, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38798093

RESUMO

PURPOSE: Antiretrovirals (ARVs) are life-saving drugs used for the treatment and prevention of HIV infection and antiviral drugs (AVs) for the treatment of chronic HBV infection. ARVs have proven highly effective in reducing perinatal HIV transmission, however the risk of birth defects from prenatal exposure to ARVs/AVs is an ongoing concern. The Antiretroviral Pregnancy Registry (APR), an international, prospective exposure-registration cohort study, monitors ARV and AV use in pregnancy for early signals of teratogenicity. This communication reports results of 30-years' experience of ARV/AV exposure during pregnancy and lessons learned through continuous quality improvement. METHODS AND RESULTS: Birth defect prevalence is estimated and compared to internal and external groups. Statistical inference is based on exact methods for binomial proportions. Between 2006 and 2023, cumulative enrollment more than tripled from 6893 to 25 960 pregnancies and ARVs/AVs monitored increased from 29 to 222. Through January 2023, there were 21 636 live births and 631 outcomes with birth defects, for overall prevalence of 2.9/100 live births (95% CI 2.7, 3.2). The birth defect prevalence was 3.0% (95% CI 2.7%, 3.3%) among first trimester exposures and 2.8% (95% CI 2.5%, 3.2%) among second/third trimester exposures (prevalence ratio 1.04 [95% CI 0.89, 1.21]). CONCLUSIONS: Birth defect prevalence is not statistically significantly different between first trimester ARV/AV pregnancy exposures compared to second/third trimester exposures and is also not different from two population-based surveillance systems: 2.72/100 live births reported in the Metropolitan Atlanta Congenital Defects Program (MACDP); and 4.17/100 live births from the Texas Birth Defects Registry (TBDR).


Assuntos
Anormalidades Induzidas por Medicamentos , Infecções por HIV , Complicações Infecciosas na Gravidez , Sistema de Registros , Humanos , Gravidez , Feminino , Estudos Prospectivos , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Adulto , Prevalência , Recém-Nascido , Antirretrovirais/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Adulto Jovem , Anormalidades Congênitas/epidemiologia , Estudos de Coortes
3.
Dent Mater ; 38(12): 1942-1946, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36347654

RESUMO

OBJECTIVES: The aim was to investigate shear bond strengths and failure modes of four self-etch bonding agents to bovine dentin and enamel and to compare evaluation of data sets with or without exclusion of cohesive failure specimens. METHODS: Composite-cylinders were bonded perpendicularly to bovine dentin and enamel surfaces. Shear-strengths were measured 24 h post-bonding of: Scotchbond Universal® (SBU, 3 M), OptiBond™ XTR (OBXTR, Kerr), OptiBond™ universal (OBU, KaVo-Kerr) and Prime & Bond active® (PBA, Dentsply-Sirona). Analysis of overall data was made via a linear mixed-model. This was repeated after exclusion of specimens associated with cohesive failures. RESULTS: When both adhesive and cohesive failures were considered, OBU and OBXTR showed comparable dentin and enamel bond strengths, whereas lower strengths were found on enamel for SBU (p < 0.001) and PBA (p = 0.015). For OBXTR higher shear strengths were measured for specimens associated with cohesive failures. When cohesive failures were excluded, the majority of shear bond strengths of adhesive failure specimens were only slightly different from overall results. However, uniquely with OBXTR dramatically lower shear bond strengths were found for dentin substrate. SIGNIFICANCE: After exclusion of cases with cohesive failures OBXTR adhesive fell behind other materials in the sequence of average shear strengths. This did not reflect the actual performance of the material. Therefore, in statistical analysis we do not recommend exclusion of data based on a specific fracture mode.


Assuntos
Colagem Dentária , Adesivos Dentinários , Bovinos , Animais , Adesivos Dentinários/química , Colagem Dentária/métodos , Dentina/química , Cimentos Dentários/química , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Resinas Compostas/química
4.
Vaccine ; 40(50): 7255-7261, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36333222

RESUMO

Rift Valley fever virus (RVFV) is an important mosquito-borne pathogen that causes outbreaks of severe disease in people and livestock throughout Africa and the Arabian Peninsula. The development of an effective veterinary and human vaccine to protect against Rift Valley fever (RVF) disease remains a high priority. The live attenuated RVFV MP-12 is a promising vaccine candidate for the prevention of RVF in both human and domestic ruminants. The aim of this study was to determine the onset of protective immunity elicted in mice by a single dose of this vaccine. Groups of CD-1 mice were vaccinated intraperitoneally with RVFV MP-12 vaccine and challenged on days 2, 5, 6 and 7 post-vaccination (PV) with a lethal dose of virulent RVFV. The mice were observed once daily for terminal morbidity and blood samples were obtained from the retro-orbital sinus complex on days 23 and 28 PV of surviving mice to determine RVFV neutralizing antibody titers. In one test, 2 of 3 mice challenged on day 2 PV survived and all 3 mice challenged at days 5 and 7 PV also survived. A second test of 10 mice per group was performed, and half (5) of those challenged at day 2 PV survived while all (10) survived challenge at day 4 and 6 PV. All surviving animals develop antibody that ranged from 1:80 to 1:1,280 PV. In a separate experiment, RVFV MP-12 vaccinated CD-1 mice, but not challenged developed a low viremia for the first 3 days PV and neutralzing antibody was detected on days 5 through day 28 PV. These findings demonstrated that the RVFV MP-12 vaccine elicited a rapid protective immune response in mice as early as 2 days PV, thus further supporting the effectiveness of this vaccine candidate for preventing RVF among humans and domestic ruminants.


Assuntos
Culicidae , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Humanos , Camundongos , Animais , Febre do Vale de Rift/prevenção & controle , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunidade
5.
Dent Mater ; 38(11): 1703-1709, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115700

RESUMO

OBJECTIVE: The aim of this study was to determine whether pretreatment of the dentin surface is beneficial or not by analysis of the bond strengths of four self-adhesive restoratives and four restoration materials where pretreatment of dentin was necessary. METHODS: Bovine incisors (n = 160) were ground flat on the labial surfaces to expose dentin using a grinder and silicon carbide (SiC) abrasive papers under running water. Between preparation and bonding procedures, the crowns were stored in Chloramine-T solution at 4 °C. Eight different restorative materials were studied: Activa BioActive (ABA), Cention Forte (CNF), Ceram.x Spectra ST (CXS), Riva self-cure (RSC), Equia Forte (EQF), Fuji II LC (FJI), Ketac Molar (KTM), Surefil one (SFO). Four materials required pretreatment of the dental hard tissue before placement, whereas the other four were self-adhesive (no pretreatment). The specimens were mounted vertically in plaster. A preload of 5 N was applied and the subsequent cross-head speed was 0.8 mm/min. Shear bond strengths (MPa) were calculated as the failure load divided by the bonding area. Failure modes were recorded as adhesive, cohesive or pretest. Data were statistically analyzed via ordinal regression for inference and Tukey's method to adjust for multiple comparisons. All computations were done using R version 4.1.2 (R Core Team 2021). RESULTS: Smax (failure stress in MPa) of the combined groups with pretreatment were significantly higher than the self-adhesive materials. The highest frequency of pretest-failure was seen with FJI. Glass-ionomer cements without pretreatment were the only restoratives with pretest failures. Amongst materials without pretreatment, SFO had the highest bond strengths. SIGNIFICANCE: The further reduction of the placement steps for materials used as an amalgam alternative, namely the omission of pretreatment of the dentin, results in these self-adhesive materials having lower bond strengths than materials that require pretreatment of the dentin.


Assuntos
Colagem Dentária , Adesivos Dentinários , Animais , Bovinos , Resinas Compostas/química , Colagem Dentária/métodos , Cimentos Dentários , Materiais Dentários , Dentina , Adesivos Dentinários/química , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Água/química
6.
R I Med J (2013) ; 105(4): 63-67, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35476741

RESUMO

BACKGROUND: The COVID-19 pandemic has presented new challenges for physicians, and physician-parents specifically. Few studies have focused on work-life changes in this population. The present study investigated work-life changes in a group of physicians during the first six months of the COVID-19 pandemic. METHODS: A survey was distributed electronically to physicians affiliated with a U.S. medical school inquiring about experiences during the first six months of the COVID-19 pandemic (March 2020 to September 2020). RESULTS: In logistic regression models adjusted for age, significantly more female physician- parents reported increased burnout, increased time with kids, and increased fear of going to work compared to male physician-parents. Around 1 in 2 attendings reported burnout, regardless of parenting status. CONCLUSION: While high rates of burnout were found across all groups in this study, differences were found by gender and parenting status. Further research is needed to understand burnout during the COVID-19 pandemic and to support physician-parents.


Assuntos
Esgotamento Profissional , COVID-19 , Médicos , Esgotamento Profissional/epidemiologia , COVID-19/epidemiologia , Feminino , Humanos , Satisfação no Emprego , Acontecimentos que Mudam a Vida , Masculino , Pandemias , Poder Familiar
7.
Nat Commun ; 12(1): 2646, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976168

RESUMO

Positron Emission Tomography (PET) is a widely-used imaging modality for medical research and clinical diagnosis. Imaging of the radiotracer is obtained from the detected hit positions of the two positron annihilation photons in a detector array. The image is degraded by backgrounds from random coincidences and in-patient scatter events which require correction. In addition to the geometric information, the two annihilation photons are predicted to be produced in a quantum-entangled state, resulting in enhanced correlations between their subsequent interaction processes. To explore this, the predicted entanglement in linear polarisation for the two photons was incorporated into a simulation and tested by comparison with experimental data from a cadmium zinc telluride (CZT) PET demonstrator apparatus. Adapted apparati also enabled correlation measurements where one of the photons had undergone a prior scatter process. We show that the entangled simulation describes the measured correlations and, through simulation of a larger preclinical PET scanner, illustrate a simple method to quantify and remove the unwanted backgrounds in PET using the quantum entanglement information alone.


Assuntos
Algoritmos , Cádmio/química , Modelos Teóricos , Fótons , Tomografia por Emissão de Pósitrons/métodos , Telúrio/química , Zinco/química , Simulação por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/instrumentação
8.
Prev Med ; 144: 106295, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33678226

RESUMO

Women with HIV bear a significant burden of Human Papillomavirus (HPV) related cervical disease, and a have a higher risk of dying from cervical cancer should it occur. WLH have increased acquisition of HPV and decreased clearance, leading to persistent HPV infection: a risk for cervical cancer. The greatest burden of HIV in women occurs in sub-Saharan Africa where diagnostic and treatment services for cervical disease are limited. This paper will describe the epidemiology of HPV related cervical disease in women living with HIV (WLH) and the efforts to treat precursor lesions in HIV treatment programs supported by the President's Emergency Plan for AIDS Relief (PEPFAR.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Neoplasias do Colo do Útero , África Subsaariana/epidemiologia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Papillomaviridae , Neoplasias do Colo do Útero/prevenção & controle
10.
BMC Urol ; 21(1): 23, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579261

RESUMO

BACKGROUND: Voluntary medical male circumcision (VMMC) is an HIV prevention strategy recommended to partially protect men from heterosexually acquired HIV. From 2015 to 2019, the President's Emergency Plan for AIDS Relief (PEPFAR) has supported approximately 14.9 million VMMCs in 15 African countries. Urethrocutaneous fistulas, abnormal openings between the urethra and penile skin through which urine can escape, are rare, severe adverse events (AEs) that can occur with VMMC. This analysis describes fistula cases, identifies possible risks and mechanisms of injury, and offers mitigation actions. METHODS: Demographic and clinical program data were reviewed from all reported fistula cases during 2015 to 2019, descriptive analyses were performed, and an odds ratio was calculated by patient age group. RESULTS: In total, 41 fistula cases were reported. Median patient age for fistula cases was 11 years and 40/41 (98%) occurred in patients aged < 15 years. Fistulas were more often reported among patients < 15 compared to ≥ 15 years old (0.61 vs. 0.01 fistulas per 100,000 VMMCs, odds ratio 50.9 (95% confidence interval [CI] = 8.6-2060.0)). Median time from VMMC surgery to appearance of fistula was 20 days (interquartile range (IQR) 14-27). CONCLUSIONS: Urethral fistulas were significantly more common in patients under age 15 years. Thinner tissue overlying the urethra in immature genitalia may predispose boys to injury. The delay between procedure and symptom onset of 2-3 weeks indicates partial thickness injury or suture violation of the urethral wall as more likely mechanisms of injury than intra-operative urethral transection. This analysis helped to inform PEPFAR's recent decision to change VMMC eligibility policy in 2020, raising the minimum age to 15 years.


Assuntos
Circuncisão Masculina/efeitos adversos , Fístula Cutânea/etiologia , Complicações Pós-Operatórias/etiologia , Doenças Uretrais/etiologia , Fístula Urinária/etiologia , Adolescente , África , Criança , Fístula Cutânea/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Tempo , Doenças Uretrais/epidemiologia , Fístula Urinária/epidemiologia
11.
Transfusion ; 61(3): 851-861, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33506960

RESUMO

BACKGROUND: To quantify the impact of the US President's Emergency Plan for AIDS Relief (PEPFAR) on the risk of HIV transmission through infected blood donations in countries supported by PEPFAR blood safety programs. METHODS: Data reported to the World Health Organization Global Database on Blood Safety were analyzed from 28 countries in sub-Saharan Africa (SSA), Asia, and the Caribbean during 2004-2015. We used the Goals model of Spectrum Spectrum System Software, version 5.53, to perform the modeling, assuming laboratory quality for HIV testing had 91.9% sensitivity and 97.7% specificity irrespective of testing method based on results of two external quality assurance and proficiency testing studies of transfusion screening for HIV in SSA blood centers. We calculated the number of new HIV infections from the number of transfusions and the prevalence of HIV infection acquired from blood transfusions with infected blood donations. We determined the impact of laboratory testing programs by estimating the number of new HIV infections averted since PEPFAR implementation. RESULTS: Assuming that HIV testing would not be performed in any of these countries without PEPFAR funding, the number of new HIV infections acquired from blood transfusions averted by laboratory testing increased over time in all 28 countries. The total number of HIV infections averted was estimated at 229 278 out of 20 428 373 blood transfusions during 2004-2015. CONCLUSION: Our mathematical modeling suggests a positive impact achieved over 12 years of PEPFAR support for blood safety. Standardized HIV testing of donated blood has reduced the risk of HIV transmission through blood transfusions in SSA, Asia, and the Caribbean.


Assuntos
Transfusão de Sangue/normas , Infecções por HIV/transmissão , Programas Nacionais de Saúde/normas , Reação Transfusional/virologia , África Subsaariana/epidemiologia , Ásia , Segurança do Sangue , Região do Caribe/epidemiologia , Testes Diagnósticos de Rotina , Infecções por HIV/sangue , Humanos , Cooperação Internacional , Programas de Rastreamento , Modelos Teóricos , Prevalência , Reação Transfusional/sangue , Organização Mundial da Saúde
12.
Comput Methods Biomech Biomed Engin ; 24(5): 485-495, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33090047

RESUMO

3D tooth models were virtually restored: flowable composite resin + bulk-fill composite (A), glass ionomer cement + bulk-fill composite (B) or adhesive + bulk-fill composite (C). Polymerization shrinkage and masticatory loads were simulated. All models exhibited the highest stress concentration at the enamel-restoration interfaces. A and C showed similar pattern with lower magnitude in A in comparison to C. B showed lower stress in dentine and C the highest cusps displacement. The use of glass ionomer cement or flowable composite resin in combination with a bulk-fill composite improved the biomechanical behavior of deep class II MO cavities.


Assuntos
Adesivos/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Análise de Elementos Finitos , Materiais Restauradores do Canal Radicular/farmacologia , Resinas Compostas/farmacologia , Reparação de Restauração Dentária , Análise do Estresse Dentário , Módulo de Elasticidade/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/farmacologia , Humanos , Teste de Materiais , Modelos Anatômicos , Polimerização , Suporte de Carga
13.
Int J Infect Dis ; 102: 544-553, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33157296

RESUMO

BACKGROUND: Female genital schistosomiasis (FGS) affects up to 56 million women in sub-Saharan Africa and may increase risk of HIV infection. METHODS: To assess the association of schistosomiasis with HIV infection, peer-reviewed literature published until 31 December 2018 was examined and a pooled estimate for the odds ratio was generated using Bayesian random effects models. RESULTS: Of the 364 abstracts that were identified, 26 were included in the summary. Eight reported odds ratios of the association between schistosomiasis and HIV; one reported a transmission hazard ratio of 1.8 (95% CI, 1.2-2.6) among women and 1.4 (95% CI, 1.0-1.9) among men; 11 described the prevalence of schistosomiasis among HIV-positive people (range, 1.5-36.6%); and six reported the prevalence of HIV among people with schistosomiasis (range, 5.8-57.3%). Six studies were selected for quantitative analysis. The pooled estimate for the odds ratio of HIV among people with schistosomiasis was 2.3 (95% CI, 1.2-4.3). CONCLUSIONS: A significant association of schistosomiasis with HIV was found. However, a specific summary estimate for FGS could not be generated. A research agenda was provided to determine the effect of FGS on HIV infection. The WHO's policy on mass drug administration for schistosomiasis may prevent HIV.


Assuntos
Infecções por HIV/complicações , Esquistossomose/complicações , África Subsaariana/epidemiologia , Teorema de Bayes , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Humanos , Masculino , Administração Massiva de Medicamentos , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose/transmissão
14.
Dent Mater ; 36(11): 1388-1396, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933776

RESUMO

OBJECTIVE: The sources of iliac crest bone grafts are limited. Alternatives are evaluated due to the progress in biomaterial sciences. Synthetical hydroxyapatite (HA), ß-tricalcium phosphate (ß-TCP) or biphasic compounds, or even a mélange of HA and ß-TCP will replace bovine ceramics. The goal is maintenance of replica-based-bone formation (RBBF) for bone augmentation. METHODS: 2 female and 2 male patients between 41 and 73 years with 5 sinus elevations were evaluated. Sinus elevations with lateral fenestration, trapezoidal-muco-periosteal flaps and filling with micro-chambered beads (1.5 mm) was performed. A porcine-collagenous membrane and the refixated flap covered the defect. A biopsy program over 20 months was confirm confirm the maintenance of the newly formed bone. RESULTS: A fast bone formation was pronounced. The biopsies revealed mature lamellar bone and full osseointegration of the ß-TCP implant. The biopsy after 20 months showed compact bone with osseointegration of minor rests of the ceramic implant. The defect revealed a mature bone stock already after 5 weeks. SIGNIFICANCE: The introduction of the replica-based-bone formation (RBBF) around micro-chambered beads will change the paradigm of bone augmentation. The next step of the ongoing study has to redefine the interval for implant insertion. The clinical approach confirms the breakthrough to primary mature lamellar bone formation and will permit reduction of placement time for a dental implant.


Assuntos
Substitutos Ósseos , Implantes Dentários , Animais , Materiais Biocompatíveis , Bovinos , Cerâmica , Implantação Dentária Endóssea , Durapatita , Feminino , Humanos , Masculino , Osseointegração , Osteogênese , Suínos
15.
Vaccine X ; 6: 100070, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-32793877

RESUMO

Rift Valley fever (RVF) poses a threat to human and animal health as well as economic losses due to abortion, new-born teratogenic effect and mortality. Safe and effective vaccines are critically needed to prevent the disease in humans and livestock. The objective of this study was to assess safety and immunogenicity of the Rift Valley fever virus (RVFV) arMP-12DNSm21/384 attenuated vaccine in 32 pregnant ewes at different stages of pregnancy including 17 ewes vaccinated during the early stage (G1) of pregnancy (<35 days) and 15 ewes vaccinated during the last two stages (G2) of pregnancy (>35 days). Ewes were monitored for clinical observations, rectal temperature and abortions and lambs were monitored for general health and rectal temperature. Vaccinated ewes and lambs were periodically sampled for their neutralizing antibody response to RVFV vaccination. All ewes were positive for antibody two weeks post-vaccination and 79% of ewes were positive at delivery. None of the 32 ewes aborted during pregnancy and all ewes vaccinated during the G2 stages of pregnancy gave birth to healthy lambs. However, among the 17 ewes vaccinated during the G1 stage of pregnancy, 2 ewes gave birth to 2 lambs with fore limb malformations that died at 1-day of age. One ewe gave birth to 2 punny twins that died at 2 days of age. Another ewe, gave birth to one lamb with a deformed tail that died at 20 days of age. At post-mortem, tissues of dead lambs (spleen, lung, brain and long bone) were negative for RVFV by PCR assay. While the findings did not link the malformed lambs directly to infection by the vaccine virus, these results indicated that pregnant sheep should not be vaccinated with the RVFV arMP-12DNSm21/384 vaccine during the first month of gestation.

16.
Phys Rev Lett ; 124(13): 132001, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302204

RESUMO

We report a measurement of the spin polarization of the recoiling neutron in deuterium photodisintegration, utilizing a new large acceptance polarimeter within the Crystal Ball at MAMI. The measured photon energy range of 300-700 MeV provides the first measurement of recoil neutron polarization at photon energies where the quark substructure of the deuteron plays a role, thereby providing important new constraints on photodisintegration mechanisms. A very high neutron polarization in a narrow structure centered around E_{γ}∼570 MeV is observed, which is inconsistent with current theoretical predictions employing nucleon resonance degrees of freedom. A Legendre polynomial decomposition suggests this behavior could be related to the excitation of the d^{*}(2380) hexaquark.

17.
BMC Urol ; 20(1): 45, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32334596

RESUMO

BACKGROUND: Male circumcision confers partial protection against heterosexual HIV acquisition among men. The President's Emergency Plan for AIDS Relief (PEPFAR) has supported > 18,900,000 voluntary medical male circumcisions (VMMC). Glans injuries (GIs) are rare but devastating adverse events (AEs) that can occur during circumcision. To address this issue, PEPFAR has supported multiple interventions in the areas of surveillance, policy, education, training, supply chain, and AE management. METHODS: Since 2015, PEPFAR has conducted surveillance of GIs including rapid investigation by the in-country PEPFAR team. This information is collected on standardized forms, which were reviewed for this analysis. RESULTS: Thirty-six GIs were reported from 2015 to 2018; all patients were < 15 years old (~ 0·7 per 100,000 VMMCs in this age group) with a decreasing annual rate (2015: 0.7 per 100,000 VMMCs; 2018: 0.4 per 100,000 VMMC; p = 0.02). Most (64%) GIs were partial or complete amputations. All amputations among 10-14 year-olds occurred using the forceps-guided (FG) method, as opposed to the dorsal-slit (DS) method, and three GIs among infants occurred using a Mogen clamp. Of 19 attempted amputation repairs, reattached tissue was viable in four (21%) in the short term. In some cases, inadequate DS method training and being overworked, were found. CONCLUSION: Following numerous interventions by PEPFAR and other stakeholders, GIs are decreasing; however, they have not been eliminated and remain a challenge for the VMMC program. Preventing further cases of complete and partial amputation will likely require additional interventions that prevent use of the FG method in young patients and the Mogen clamp in infants. Improving management of GIs is critical to optimizing outcomes.


Assuntos
Circuncisão Masculina/efeitos adversos , Infecções por HIV/prevenção & controle , Complicações Intraoperatórias/etiologia , Pênis/lesões , Adolescente , África Oriental , África Austral , Criança , Pré-Escolar , Humanos , Lactente , Masculino
18.
Astrophys J ; 889(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32255818

RESUMO

We explore the fundamental limits to which reionization histories can be constrained using only large-scale cosmic microwave background (CMB) anisotropy measurements. The redshift distribution of the fractional ionization x e (z) affects the angular distribution of CMB polarization. We project constraints on the reionization history of the universe using low-noise full-sky temperature and E-mode measurements of the CMB. We show that the measured TE power spectrum, C ^ ℓ TE , has roughly one quarter of the constraining power of C ^ ℓ EE on the reionization optical depth τ, and its addition improves the precision on τ by 20% over using C ^ ℓ EE only. We also use a two-step reionization model with an additional high-redshift step, parameterized by an early ionization fraction x e min , and a late reionization step at z re. We find that future high signal-to-noise measurements of the multipoles 10 ⩽ ℓ < 20 are especially important for breaking the degeneracy between x e min and z re. In addition, we show that the uncertainties on these parameters determined from a map with sensitivity 10 µK arcmin are less than 5% larger than the uncertainties in the noiseless case, making this noise level a natural target for future large sky area E-mode measurements.

19.
J Acquir Immune Defic Syndr ; 82(2): 181-187, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513074

RESUMO

BACKGROUND: Women living with HIV (WLHIV) have increased risk of spontaneous preterm delivery (SPTD). We sought to identify plasma predictors of SPTD and their correlations with factors that increase the risk of SPTD, such as vitamin D deficiency and use of protease inhibitors. DESIGN: Plasma was obtained from 103 WLHIV with SPTD (≤35 weeks gestation) and 205 controls with term deliveries (TDs; ≥37 weeds) matched to cases 2:1 by race and gestational age at blood draw. TNFα, IFNγ, IL6, IL8, IL1ß, IL18, IL17, granulocyte colony stimulating factor (GCSF), MCP1, IP10, sIL2Rα, sCD14, vascular endothelial factor a, monocyte colony stimulation factor, GROα, MMP9, IL10, TGFß, sCTLA4, and eicosanoids were compared between cases adjusting for known SPTD risk factors. RESULTS: Participants had similar demographic characteristics, but cases had higher plasma HIV RNA, lower CD4 cells, and more advanced HIV disease compared with controls. High sIL2Rα was associated with increased risk of SPTD. High sCD14, GCSF, PGF2α, and 5-HEPE were marginally associated with increased risk of SPTD. Women who initiated protease inhibitors-containing antiretroviral treatment before or during the first trimester had higher levels of GCSF and 5-HEPE compared with women without such exposure before plasma collection. Vitamin D insufficiency was associated with higher inflammatory sCD14 and PGF2α, and lower anti-inflammatory 5-HEPE. CONCLUSIONS: The best plasma predictor of SPTD in WLHIV was sIL2Rα, a marker of T-cell activation. Markers of monocyte activation and eicosanoids were marginally increased in WLHIV and SPTD, suggesting that they may also play a role in the pathogenesis of this disorder.


Assuntos
Infecções por HIV/sangue , Inibidores da Protease de HIV/uso terapêutico , Complicações Infecciosas na Gravidez/sangue , Nascimento Prematuro/etiologia , Vitamina D/análogos & derivados , Biomarcadores/sangue , Eicosanoides/sangue , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Subunidade alfa de Receptor de Interleucina-2/sangue , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , RNA Viral/análise , Vitamina D/sangue
20.
Dent Mater ; 35(8): 1166-1172, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31146959

RESUMO

OBJECTIVES: To study the effect of water storage (3 months) on the creep deformation and recovery of CAD/CAM composite materials to determine their viscoelastic stability. MATERIALS AND METHODS: Five CAD/CAM composite blocks, with increasing filler loading, and one polymer-infiltrated ceramic network (PICN) were studied. Six specimens of each material were separated into two groups (n=3) according to their storage conditions (24 h dry storage at 23°C versus 3 months storage in 37°C distilled water). A constant static compressive stress of 20 MPa was applied on each specimen via a loading pin for 2 h followed by unloading and monitoring strain recovery for a further period of 2 h. The maximum creep-strain (%) and permanent set (%) were recorded. Data were analysed via two-way ANOVA followed by one-way ANOVA and Bonferroni post hoc tests (<0.05) for comparisons between the materials. Homogeneity of variance was calculated via Levene's statistics. RESULTS: The maximum creep strain after 24 h dry ranged from 0.45% to 1.09% and increased after 3-month storage in distilled water to between 0.71% and 1.85%. The permanent set after 24 h dry storage ranged from 0.033% to 0.15% and increased after 3-month water storage to between 0.087% and 0.18%. The maximum creep strain also reduced with increasing filler loading. SIGNIFICANCE: The PICN material exhibited superior dimensional stability to all of the pre-cured resin composite blocks in both storage conditions with deformation being predominantly elastic rather than viscoelastic. Notwithstanding, two of the resin-matrix composite blocks approached the PICN performance, when dry, but less so after water storage.


Assuntos
Resinas Compostas , Desenho Assistido por Computador , Cerâmica , Análise do Estresse Dentário , Teste de Materiais , Propriedades de Superfície
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