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1.
Nature ; 587(7833): 205-209, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33106686

RESUMO

An asteroid's history is determined in large part by its strength against collisions with other objects1,2 (impact strength). Laboratory experiments on centimetre-scale meteorites3 have been extrapolated and buttressed with numerical simulations to derive the impact strength at the asteroid scale4,5. In situ evidence of impacts on boulders on airless planetary bodies has come from Apollo lunar samples6 and images of the asteroid (25143) Itokawa7. It has not yet been possible, however, to assess directly the impact strength, and thus the absolute surface age, of the boulders that constitute the building blocks of a rubble-pile asteroid. Here we report an analysis of the size and depth of craters observed on boulders on the asteroid (101955) Bennu. We show that the impact strength of metre-sized boulders is 0.44 to 1.7 megapascals, which is low compared to that of solid terrestrial materials. We infer that Bennu's metre-sized boulders record its history of impact by millimetre- to centimetre-scale objects in near-Earth space. We conclude that this population of near-Earth impactors has a size frequency distribution similar to that of metre-scale bolides and originates from the asteroidal population. Our results indicate that Bennu has been dynamically decoupled from the main asteroid belt for 1.75 ± 0.75 million years.

2.
Nature ; 561(7722): 206-210, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30209369

RESUMO

Earth and its magnetosphere are immersed in the supersonic flow of the solar-wind plasma that fills interplanetary space. As the solar wind slows and deflects to flow around Earth, or any other obstacle, a 'bow shock' forms within the flow. Under almost all solar-wind conditions, planetary bow shocks such as Earth's are collisionless, supercritical shocks, meaning that they reflect and accelerate a fraction of the incident solar-wind ions as an energy dissipation mechanism1,2, which results in the formation of a region called the ion foreshock3. In the foreshock, large-scale, transient phenomena can develop, such as 'hot flow anomalies'4-9, which are concentrations of shock-reflected, suprathermal ions that are channelled and accumulated along certain structures in the upstream magnetic field. Hot flow anomalies evolve explosively, often resulting in the formation of new shocks along their upstream edges5,10, and potentially contribute to particle acceleration11-13, but there have hitherto been no observations to constrain this acceleration or to confirm the underlying mechanism. Here we report observations of a hot flow anomaly accelerating solar-wind ions from roughly 1-10 kiloelectronvolts up to almost 1,000 kiloelectronvolts. The acceleration mechanism depends on the mass and charge state of the ions and is consistent with first-order Fermi acceleration14,15. The acceleration that we observe results from only the interaction of Earth's bow shock with the solar wind, but produces a much, much larger number of energetic particles compared to what would typically be produced in the foreshock from acceleration at the bow shock. Such autogenous and efficient acceleration at quasi-parallel bow shocks (the normal direction of which are within about 45 degrees of the interplanetary magnetic field direction) provides a potential solution to Fermi's 'injection problem', which requires an as-yet-unexplained seed population of energetic particles, and implies that foreshock transients may be important in the generation of cosmic rays at astrophysical shocks throughout the cosmos.

3.
Subst Use Misuse ; 59(7): 1031-1038, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38403989

RESUMO

INTRODUCTION: Although Indian Americans constitute the second-largest immigrant group in the United States, there is a paucity of information about Indian American youth, particularly with respect to substance use risk. We examined the relationship of social factors to permissive substance use beliefs (a proxy for substance use risk since they can lead to adulthood substance use and misuse) and family functioning. METHODS: The study used structural equation modeling to examine the prevalence of permissive substance use beliefs in a sample of Indian American youth ages 12-17 (N = 223) and examined the degree to which discrimination, bicultural identity integration, and endorsement of the model minority stereotype were associated with permissive substance use beliefs. RESULTS: Findings suggest that bicultural identity integration (B = 0.267 [SE = 0.112], p = 0.01) and discrimination (B = 0.294 [SE = 0.087], p = 0.001) are positively associated with permissive substance use beliefs. Bicultural identity integration (B = 0.415 [SE = 0.090], p = 0.0001) was positively associated with family support (B= -0.329 [SE = 0.108], p = 0.002) which, in turn, was associated with less permissive substance use beliefs. In contrast, endorsement of the model minority stereotype (B = 0.351 [SE = 0.090], p = 0.001) was positively associated with family closeness (B = 0.232 [SE = 0.927], p = 0.01) which, in turn, was associated with family support and then with less permissive substance use beliefs. CONCLUSIONS: Discrimination and bicultural identity integration emerged as key constructs related to substance use risk among Indian American youth. These youth could benefit from culturally appropriate prevention programming that addresses the negative impact of discrimination and its effect on permissive substance use beliefs and highlights protective factors.


Assuntos
Comportamento do Adolescente , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Humanos , Grupos Minoritários , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Estados Unidos/epidemiologia , Asiático , Cultura , Criança , Apoio Familiar
4.
Soc Psychiatry Psychiatr Epidemiol ; 58(7): 1075-1085, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36564584

RESUMO

PURPOSE: Rooted in a trans-territorial framework, the present study was designed to provide new evidence regarding the patterns of communication among Hurricane Maria survivors who migrated to the U.S. in the aftermath of the storm. METHODS: A total of 319 Hurricane Maria survivor adults ages 18 and older were recruited into the Adelante Boricua study between August 2020 and October 2021. Most participants had relocated to the U.S. between 2017 and 2018. We used latent profile analysis and multinomial regression to examine the relationship of technology-based communication with depressive symptoms, well-being, cultural connection, and migration stress. RESULTS: We identified a five-class solution, consisting of (1) moderate communication (32%), (2) disengaged (24%), (3) no social media (18%), (4) daily with family in Puerto Rico (6%), and (5) daily trans-territorial (13%) typologies. Participants in the disengaged class were more likely to report elevated depressive symptoms and limited English proficiency, lower prosocial behaviors, lower levels of religiosity, lower attendance at religious services in the U.S., and less engagement in social activities, compared to participants in the Moderate Communication class. CONCLUSION: Roughly one in four individuals in our sample reported very limited technology-based communication with friends/family in their sending and new-receiving communities. As technology and smartphones continue to become integrated into 21st-century life, it is vital that researchers explore how the tremendous potential for connectedness relates to trans-territorial crisis migrants' well-being and adaptation.


Assuntos
Tempestades Ciclônicas , Migrantes , Adulto , Estados Unidos , Humanos , Porto Rico
5.
Rev Sci Tech ; 42: 65-74, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37232318

RESUMO

Environmental exposures can have large impacts on health outcomes. While many resources have been dedicated to understanding how humans are influenced by the environment, few efforts have been made to study the role of built and natural environmental features on animal health. The Dog Aging Project (DAP) is a longitudinal community science study of aging in companion dogs. Using a combination of owner-reported surveys and secondary sources linked through geocoded coordinates, DAP has captured home, yard and neighbourhood variables for over 40,000 dogs. The DAP environmental data set spans four domains: the physical and built environment; chemical environment and exposures; diet and exercise; and social environment and interactions. By combining biometric data, measures of cognitive function and behaviour, and medical records, DAP is attempting to use a big-data approach to transform the understanding of how the surrounding world affects the health of companion dogs. In this paper, the authors describe the data infrastructure developed to integrate and analyse multi-level environmental data that can be used to improve the understanding of canine co-morbidity and aging.


L'impact des expositions environnementales sur la santé est parfois considérable. Si diverses ressources ont été consacrées à décrire l'influence de l'environnement sur les humains, les efforts visant à étudier l'effet des paramètres environnementaux, tant naturels qu'anthropiques, sur la santé animale sont plus rares. Le Dog Aging Project (DAP) est une étude scientifique longitudinale à base communautaire portant sur le vieillissement du chien de compagnie. À partir d'observations notifiées par les propriétaires de chiens et de sources secondaires reliées par des coordonnées de géocodage, le DAP a réuni des variables sur le foyer d'habitation, l'environnement extérieur immédiat et le voisinage de plus de 40 000 chiens. Les séries de données environnementales du DAP couvrent quatre domaines : l'environnement physique et bâti ; l'environnement chimique et les expositions ; le régime alimentaire et la dépense physique ; et les interactions et l'environnement social. En combinant les données biométriques, les mesures du fonctionnement cognitif et comportemental et les dossiers médicaux, le DAP cherche à utiliser l'approche des mégadonnées pour transformer notre perception de la manière dont le monde qui nous entoure affecte la santé des chiens de compagnie. Les auteurs décrivent l'infrastructure des données mise au point pour intégrer et analyser des données environnementales multi-niveaux, afin de mieux comprendre les phénomènes de comorbidité et de vieillissement chez le chien.


La exposición a factores ambientales puede tener muchas e importantes repercusiones en los resultados sanitarios. Si bien se han dedicado cuantiosos recursos a aprehender la influencia del entorno en las personas, poco se ha hecho para estudiar el modo en que las características del medio, tanto natural como artificial, repercuten en la salud de los animales. El proyecto sobre Envejecimiento canino [Dog Aging Project: DAP] es un estudio longitudinal de ciencia ciudadana centrado en el envejecimiento de los perros de compañía. Combinando la información de encuestas realizadas a propietarios y de fuentes secundarias y vinculando los datos a coordenadas geográficas codificadas, el DAP ha permitido reunir información de variables ligadas al hogar, el jardín y el barrio de más de 40 000 perros. El conjunto de datos ambientales del DAP cubre cuatro grandes ámbitos: medio físico y urbanizado; condiciones químicas del entorno y exposición a sustancias químicas; régimen alimentario y ejercicio; y medio e interacciones sociales. Pasando por el uso combinado de datos biométricos, historias clínicas y mediciones de la función cognitiva y el comportamiento, el DAP apunta ahora a emplear técnicas de trabajo con macrodatos para hacer evolucionar nuestras ideas sobre la influencia del mundo que nos rodea en la salud de los perros de compañía. Los autores describen la infraestructura de datos establecida para integrar y analizar datos ambientales multiestratificados que nos ayuden a conocer mejor los procesos de comorbilidad y envejecimiento en el perro.


Assuntos
Envelhecimento , Big Data , Humanos , Cães , Animais , Estudos Longitudinais , Dieta , Animais de Estimação
6.
Rev Geophys ; 58(1): e2019RG000660, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32734279

RESUMO

Aerosols interact with radiation and clouds. Substantial progress made over the past 40 years in observing, understanding, and modeling these processes helped quantify the imbalance in the Earth's radiation budget caused by anthropogenic aerosols, called aerosol radiative forcing, but uncertainties remain large. This review provides a new range of aerosol radiative forcing over the industrial era based on multiple, traceable, and arguable lines of evidence, including modeling approaches, theoretical considerations, and observations. Improved understanding of aerosol absorption and the causes of trends in surface radiative fluxes constrain the forcing from aerosol-radiation interactions. A robust theoretical foundation and convincing evidence constrain the forcing caused by aerosol-driven increases in liquid cloud droplet number concentration. However, the influence of anthropogenic aerosols on cloud liquid water content and cloud fraction is less clear, and the influence on mixed-phase and ice clouds remains poorly constrained. Observed changes in surface temperature and radiative fluxes provide additional constraints. These multiple lines of evidence lead to a 68% confidence interval for the total aerosol effective radiative forcing of -1.6 to -0.6 W m-2, or -2.0 to -0.4 W m-2 with a 90% likelihood. Those intervals are of similar width to the last Intergovernmental Panel on Climate Change assessment but shifted toward more negative values. The uncertainty will narrow in the future by continuing to critically combine multiple lines of evidence, especially those addressing industrial-era changes in aerosol sources and aerosol effects on liquid cloud amount and on ice clouds.

7.
Osteoarthritis Cartilage ; 28(6): 755-765, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32200051

RESUMO

OBJECTIVE: Different exercise types may yield different outcomes in osteoarthritis (OA) subgroups. The objective was to directly compare effectiveness of two exercise programs for people with medial knee OA and co-morbid obesity. DESIGN: We performed a participant- and assessor-blinded randomized controlled trial. 128 people ≥50 years with medial knee OA and body mass index ≥30 kg/m2 were recruited from the community. Interventions were home-based non-weight bearing (NWB) quadriceps strengthening or weight bearing (WB) functional exercise for 12 weeks. Primary outcomes were change in overall knee pain (numeric rating scale, range 0-10) and difficulty with physical function (Western Ontario and McMaster Universities Osteoarthritis Index, 0-68) over 12 weeks. Secondary outcomes included other pain measures, physical function, quality-of-life, global changes, physical performance, and lower-limb muscle strength. RESULTS: 123 (96%) participants were retained. There was no evidence of a between-group difference in change in pain (mean difference 0.73 units (95% confidence intervals (0.05,1.50)) or function (2.80 units (-1.17,6.76)), with both groups reporting improvements. For secondary outcomes, the WB group had greater improvement in quality-of-life (-0.043 units (-0.085,-0.001)) and more participants reporting global improvement (overall: relative risk 1.40 (0.98,2.01); pain 1.47 (0.97,2.24); function 1.43 (1.04,1.98). Although adverse events were minor, more NWB group participants reported ≥1 adverse event (26/66 (39%) vs 14/62 (23%), p = 0.04). CONCLUSIONS: Both exercise types similarly improved primary outcomes of pain and function and can be recommended for people with knee OA and obesity. WB exercise may be preferred given fewer adverse events and potential additional benefits on some secondary outcomes. REGISTRATION: Prospectively registered (Australian New Zealand Clinical Trials Registry #12617001013358, 14/7/2017).


Assuntos
Terapia por Exercício/métodos , Obesidade Mórbida/complicações , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/terapia , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Suporte de Carga
8.
Curr HIV/AIDS Rep ; 17(5): 467-477, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32860150

RESUMO

PURPOSE OF REVIEW: Aligning HIV treatment services with patient preferences can promote long-term engagement. A rising number of studies solicit such preferences using discrete choice experiments, but have not been systematically reviewed to seek generalizable insights. Using a systematic search, we identified eleven choice experiments evaluating preferences for HIV treatment services published between 2004 and 2020. RECENT FINDINGS: Across settings, the strongest preference was for nice, patient-centered providers, for which participants were willing to trade considerable amounts of time, money, and travel distance. In low- and middle-income countries, participants also preferred collecting antiretroviral therapy (ART) less frequently than 1 monthly, but showed no strong preference for 3-compared with 6-month refill frequency. Facility waiting times and travel distances were also important but were frequently outranked by stronger preferences. Health facility-based services were preferred to community- or home-based services, but this preference varied by setting. In high-income countries, the availability of unscheduled appointments was highly valued. Stigma was rarely explored and costs were a ubiquitous driver of preferences. While present improvement efforts have focused on designs to enhance access (reduced waiting time, travel distance, and ART refill frequency), few initiatives focus on the patient-provider interaction, which represents a promising critical area for inquiry and investment. If HIV programs hope to truly deliver patient-centered care, they will need to incorporate patient preferences into service delivery strategies. Discrete choice experiments can not only inform such strategies but also contribute to prioritization efforts for policy-making decisions.


Assuntos
Antirretrovirais/uso terapêutico , Atenção à Saúde/métodos , Infecções por HIV/tratamento farmacológico , Serviços de Saúde , Preferência do Paciente/psicologia , Assistência Centrada no Paciente/métodos , Adulto , Agendamento de Consultas , Comportamento de Escolha , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Relações Médico-Paciente
9.
AIDS Behav ; 23(Suppl 2): 194, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31542878

RESUMO

The article "Leveraging Geospatial Approaches to Characterize the HIV Prevention and Treatment Needs of Out-of-School Adolescent Girls and Young Women in Ethiopia" written by Y. Wang, C. A. Comins, A. Mulu, S. A. Abebe, K. Belete, T. T. Balcha, S. Baral, S. R. Schwartz, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 27th May 2019 without open access. With the author(s)' decision to opt for Open Choice the copyright of the article changed on 19th September 2019 to © The Author(s) 2019 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, duplication, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

10.
AIDS Behav ; 23(Suppl 2): 183-193, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31134462

RESUMO

Adolescent girls and young women (AGYW) remain underserved and at risk for HIV acquisition in Ethiopia. However, there is significant risk heterogeneity among AGYW with limited consensus on optimal strategies of identifying vulnerable AGYW. This study assessed the utility of venue-based sampling approaches to identify AGYW at increased risk for HIV infection. Venue mapping and time-location-sampling (TLS) methods were used to recruit AGYW from three sub-cities of Addis Ababa, February-June 2018. Interviewer-administered surveys captured socio-demographic and behavioral characteristics. Measures of AGYW vulnerability were assessed geographically and described by venue type. A total of 2468 unique venues were identified, of which 802 (32%) were systematically selected for validation and 371 (46%) were eligible including many sites that would traditionally not be included as venues in need of HIV prevention services. Overall, 800 AGYW were enrolled across 81 sampled venues. AGYW reached were largely out-of-school (n = 599, 75%) with high proportions of AGYW reporting transactional sex (n = 101, 12.6%), food insecurity (n = 165, 20.7%) and migration (n = 565, 70.6%). Taken together, these data suggest the utility of TLS methods in reaching vulnerable, out-of-school AGYW in Addis Ababa, Ethiopia.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Programas de Rastreamento , Comportamento Sexual/estatística & dados numéricos , População Suburbana/estatística & dados numéricos , Adolescente , Demografia , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Instituições Acadêmicas , Fatores Socioeconômicos , Adulto Jovem
11.
Phys Rev Lett ; 120(22): 225101, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906189

RESUMO

Electron heating at Earth's quasiperpendicular bow shock has been surmised to be due to the combined effects of a quasistatic electric potential and scattering through wave-particle interaction. Here we report the observation of electron distribution functions indicating a new electron heating process occurring at the leading edge of the shock front. Incident solar wind electrons are accelerated parallel to the magnetic field toward downstream, reaching an electron-ion relative drift speed exceeding the electron thermal speed. The bulk acceleration is associated with an electric field pulse embedded in a whistler-mode wave. The high electron-ion relative drift is relaxed primarily through a nonlinear current-driven instability. The relaxed distributions contain a beam traveling toward the shock as a remnant of the accelerated electrons. Similar distribution functions prevail throughout the shock transition layer, suggesting that the observed acceleration and thermalization is essential to the cross-shock electron heating.

12.
Geophys Res Lett ; 45(10): 4569-4577, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31031447

RESUMO

Magnetospheric Multiscale observations are used to probe the structure and temperature profile of a guide field reconnection exhaust ~100 ion inertial lengths downstream from the X-line in the Earth's magnetosheath. Asymmetric Hall electric and magnetic field signatures were detected, together with a density cavity confined near 1 edge of the exhaust and containing electron flow toward the X-line. Electron holes were also detected both on the cavity edge and at the Hall magnetic field reversal. Predominantly parallel ion and electron heating was observed in the main exhaust, but within the cavity, electron cooling and enhanced parallel ion heating were found. This is explained in terms of the parallel electric field, which inhibits electron mixing within the cavity on newly reconnected field lines but accelerates ions. Consequently, guide field reconnection causes inhomogeneous changes in ion and electron temperature across the exhaust.

13.
Ultrasound Obstet Gynecol ; 52(5): 662-665, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29575202

RESUMO

OBJECTIVE: Intra-abdominal adhesions are associated with an increased risk of complications during repeat Cesarean section (CS), such as bladder and bowel injury, hemorrhage, infection and hysterectomy. We present a simple sonographic marker, the 'sliding sign' of the uterus, for the prediction of intra-abdominal adhesions in the third trimester of pregnancy in women undergoing repeat CS. METHODS: This was a prospective observational study of pregnant women with a history of at least one Cesarean delivery evaluated by transabdominal ultrasound during the third trimester of an ongoing pregnancy. In order to diagnose intra-abdominal adhesions, we assessed a sonographic sign, the sliding of the uterus under the inner part of the fascia of the abdominal muscles during deep breathing. Women were considered to be at high risk for severe adhesions if uterine sliding was absent and at low risk in the presence of obvious or moderate uterine sliding. A comparison between sonographic findings and intra-abdominal adhesions observed during surgery was performed. RESULTS: Of the 63 patients with one or more previous CS examined, 59 completed the study and underwent CS at our institution. In 16 of the 19 cases assigned to the high-risk group for severe adhesions due to absence of sliding of the uterus, the suspicion was confirmed at surgery. The prediction of low risk for adhesions was confirmed in 35 out of 40 patients. The sensitivity and specificity of the sliding sign in predicting presence of intra-abdominal adhesions in women undergoing repeat CS were 76.2% and 92.1%, respectively. Inter- and intraobserver correlation using Cohen's kappa coefficient were 0.52 and 0.77, respectively. CONCLUSION: Our data show that a simple sonographic sign might be able to discriminate between high and low risk for intra-abdominal adhesions in patients with a history of Cesarean delivery. This technique may aid clinical decisions in patients undergoing repeat CS. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Recesariana/efeitos adversos , Aderências Teciduais/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos
14.
Prenat Diagn ; 38(3): 210-218, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29338128

RESUMO

OBJECTIVE: Screening via noninvasive prenatal testing (NIPT) involving the analysis of cell-free DNA (cfDNA) from plasma has become readily available to screen for chromosomal and DNA aberrations through maternal blood. This report reviews a laboratory's experience with follow-up of positive NIPT screens for microdeletions. METHODS: Patients that were screened positive by NIPT for a microdeletion involving 1p, 4p, 5p, 15q, or 22q who underwent diagnostic studies by either chorionic villus sampling or amniocentesis were evaluated. RESULTS: The overall positive predictive value for 349 patients was 9.2%. When a microdeletion was confirmed, 39.3% of the cases had additional abnormal microarray findings. Unrelated abnormal microarray findings were detected in 11.8% of the patients in whom the screen positive microdeletion was not confirmed. Stretches of homozygosity in the microdeletion were frequently associated with a false positive cfDNA microdeletion result. CONCLUSIONS: Overall, this report reveals that while cfDNA analysis will screen for microdeletions, the positive predictive value is low; in our series it is 9.2%. Therefore, the patient should be counseled accordingly. Confirmatory diagnostic microarray studies are imperative because of the high percentage of false positives and the frequent additional abnormalities not delineated by cfDNA analysis.


Assuntos
Ácidos Nucleicos Livres/análise , Testes para Triagem do Soro Materno , Deleção de Sequência , Aberrações Cromossômicas , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos
15.
Ann Oncol ; 27(7): 1207-25, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052648

RESUMO

Infections of the central nervous system (CNS) are infrequently diagnosed in immunocompetent patients, but they do occur in a significant proportion of patients with hematological disorders. In particular, patients undergoing allogeneic hematopoietic stem-cell transplantation carry a high risk for CNS infections of up to 15%. Fungi and Toxoplasma gondii are the predominant causative agents. The diagnosis of CNS infections is based on neuroimaging, cerebrospinal fluid examination and biopsy of suspicious lesions in selected patients. However, identification of CNS infections in immunocompromised patients could represent a major challenge since metabolic disturbances, side-effects of antineoplastic or immunosuppressive drugs and CNS involvement of the underlying hematological disorder may mimic symptoms of a CNS infection. The prognosis of CNS infections is generally poor in these patients, albeit the introduction of novel substances (e.g. voriconazole) has improved the outcome in distinct patient subgroups. This guideline has been developed by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) with the contribution of a panel of 14 experts certified in internal medicine, hematology/oncology, infectious diseases, intensive care, neurology and neuroradiology. Grades of recommendation and levels of evidence were categorized by using novel criteria, as recently published by the European Society of Clinical Microbiology and Infectious Diseases.


Assuntos
Sistema Nervoso Central/fisiopatologia , Doenças Transmissíveis/fisiopatologia , Doenças Hematológicas/microbiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Sistema Nervoso Central/microbiologia , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/microbiologia , Alemanha/epidemiologia , Guias como Assunto , Doenças Hematológicas/tratamento farmacológico , Doenças Hematológicas/epidemiologia , Doenças Hematológicas/fisiopatologia , Hematologia , Humanos , Oncologia , Toxoplasma/patogenicidade , Voriconazol/uso terapêutico
16.
Phys Rev Lett ; 116(10): 102502, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-27015475

RESUMO

The thermonuclear ^{30}P(p,γ)^{31}S reaction rate is critical for modeling the final elemental and isotopic abundances of ONe nova nucleosynthesis, which affect the calibration of proposed nova thermometers and the identification of presolar nova grains, respectively. Unfortunately, the rate of this reaction is essentially unconstrained experimentally, because the strengths of key ^{31}S proton capture resonance states are not known, largely due to uncertainties in their spins and parities. Using the ß decay of ^{31}Cl, we have observed the ß-delayed γ decay of a ^{31}S state at E_{x}=6390.2(7) keV, with a ^{30}P(p,γ)^{31}S resonance energy of E_{r}=259.3(8) keV, in the middle of the ^{30}P(p,γ)^{31}S Gamow window for peak nova temperatures. This state exhibits isospin mixing with the nearby isobaric analog state at E_{x}=6279.0(6) keV, giving it an unambiguous spin and parity of 3/2^{+} and making it an important l=0 resonance for proton capture on ^{30}P.

17.
Phys Rev Lett ; 117(16): 165101, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27792387

RESUMO

Collisionless shock nonstationarity arising from microscale physics influences shock structure and particle acceleration mechanisms. Nonstationarity has been difficult to quantify due to the small spatial and temporal scales. We use the closely spaced (subgyroscale), high-time-resolution measurements from one rapid crossing of Earth's quasiperpendicular bow shock by the Magnetospheric Multiscale (MMS) spacecraft to compare competing nonstationarity processes. Using MMS's high-cadence kinetic plasma measurements, we show that the shock exhibits nonstationarity in the form of ripples.

18.
Phys Rev Lett ; 117(1): 015001, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27419573

RESUMO

We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E_{∥}) that is larger than predicted by simulations. The high-speed (∼300 km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E_{∥} is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.

19.
Phys Rev Lett ; 116(23): 235102, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27341241

RESUMO

We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100 mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.

20.
Gynecol Oncol ; 140(3): 565-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26812021

RESUMO

Obstetrician/gynecologists and gynecologic oncologists serve an integral role in the care of women at increased hereditary risk of cancer. Their contribution includes initial identification of high risk patients, screening procedures like bimanual exam, trans-vaginal ultrasound and endometrial biopsy, prophylaxis via TAH and/or BSO, and chemoprevention. Further, gynecologists also serve a central role in the management of the secondary repercussions of efforts to mitigate increased cancer risks, including vasomotor symptoms, sexual function, bone health, cardiovascular disease, and mental health. The past several years has seen multiple new high and moderate penetrance genes introduced into the clinical care of women at increased risk of gynecologic malignancy. Awareness of these new genes and the availability of new multi-gene panel tests is critical for providers on the front-line of women's health.


Assuntos
Neoplasias da Mama/genética , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Genes BRCA1 , Genes BRCA2 , Testes Genéticos , Neoplasias dos Genitais Femininos/genética , Adulto , Quimioprevenção , Detecção Precoce de Câncer , Feminino , Preservação da Fertilidade , Predisposição Genética para Doença , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Femininos/prevenção & controle , Humanos , Pessoa de Meia-Idade , Mutação , Penetrância , Procedimentos Cirúrgicos Profiláticos , Saúde Reprodutiva , Medição de Risco
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