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1.
Phys Rev Lett ; 130(5): 051801, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800472

RESUMO

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νßß) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νßß decay half-life of T_{1/2}^{0ν}>2.3×10^{26} yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

2.
Geophys Res Lett ; 49(14): e2022GL098329, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-36249284

RESUMO

Geospace plasma simulations have progressed toward more realistic descriptions of the solar wind-magnetosphere interaction from magnetohydrodynamic to hybrid ion-kinetic, such as the state-of-the-art Vlasiator model. Despite computational advances, electron scales have been out of reach in a global setting. eVlasiator, a novel Vlasiator submodule, shows for the first time how electromagnetic fields driven by global hybrid-ion kinetics influence electrons, resulting in kinetic signatures. We analyze simulated electron distributions associated with reconnection sites and compare them with Magnetospheric Multiscale (MMS) spacecraft observations. Comparison with MMS shows that key electron features, such as reconnection inflows, heated outflows, flat-top distributions, and bidirectional streaming, are in remarkable agreement. Thus, we show that many reconnection-related features can be reproduced despite strongly truncated electron physics and an ion-scale spatial resolution. Ion-scale dynamics and ion-driven magnetic fields are shown to be significantly responsible for the environment that produces electron dynamics observed by spacecraft in near-Earth plasmas.

3.
J Geophys Res Space Phys ; 127(7): e2022JA030408, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36248013

RESUMO

We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.

4.
J Vet Cardiol ; 43: 101-103, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36116206

RESUMO

A one-year-old neutered, Goldendoodle presented for evaluation. One week prior to presentation, the surgical closure of a peritoneopericardial diaphragmatic hernia was performed via ventral midline celiotomy. Since the procedure, the dog had been lethargic and anorexic at home. Thoracic radiographs revealed a pneumopericardium. Pericardiocentesis was performed which evacuated approximately 100 mL of air from the pericardial sac. The dog recovered well and began eating in the hospital and resumed normal activity. This is the first reported case of a pneumopericardium post-peritoneopericardial diaphragmatic hernia repair requiring pericardiocentesis. Clinicians should be aware of this rare complication in patients with post-operative peritoneopericardial diaphragmatic hernia.


Assuntos
Doenças do Cão , Hérnia Diafragmática , Pneumopericárdio , Animais , Cães , Diafragma , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/etiologia , Doenças do Cão/cirurgia , Hérnia Diafragmática/diagnóstico por imagem , Hérnia Diafragmática/cirurgia , Hérnia Diafragmática/veterinária , Pericárdio , Pneumopericárdio/diagnóstico por imagem , Pneumopericárdio/etiologia , Pneumopericárdio/veterinária
5.
J Vet Cardiol ; 43: 1-9, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35870399

RESUMO

OBJECTIVE: The aim of this paper is to evaluate owners' chronic medication adherence for management of feline cardiovascular disease in the small animal referral setting. ANIMALS, MATERIALS AND METHODS: A questionnaire-based study of owners at five multispecialty, small animal referral centers was conducted. Owners completed a written survey evaluating demographics, degree of medication adherence, and difficulties encountered for medication adherence. Owners were free to decline participation in the study. RESULTS: Fifty-four questionnaires were available for review. The most common diagnosis was hypertrophic cardiomyopathy (n = 31, 57.4%). Clopidogrel was the most cited medication that was difficult to administer consistently (n = 13, 24.0%) although twenty owners (37.0%) reported no difficulty consistently administering medications. "Taste of medication" (n = 14, 25.9%) was the most reported reason for difficulty medicating their cat, and most owners (n = 36, 66.7%) stated twice daily was the highest frequency of heart medications they feel they can consistently administer. Fifty owners (92.6%) met the criteria for medication adherence. CONCLUSIONS: Chronic medication adherence in this study population was high. Clopidogrel was the most difficult medication to consistently administer, and twice a day dosing was the highest frequency of medication administration most owners could achieve. Cardiologists should be aware of these factors when determining optimal treatment protocols for the management of cardiovascular disease in cats.


Assuntos
Doenças Cardiovasculares , Doenças do Gato , Gatos , Animais , Propriedade , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/veterinária , Clopidogrel/uso terapêutico , Inquéritos e Questionários , Adesão à Medicação , Encaminhamento e Consulta , Doenças do Gato/tratamento farmacológico
6.
Phys Rev Lett ; 127(21): 215101, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34860109

RESUMO

We report in situ observations of an electron diffusion region (EDR) and adjacent separatrix region in the Earth's magnetotail. We observe significant magnetic field oscillations near the lower hybrid frequency which propagate perpendicularly to the reconnection plane. We also find that the strong electron-scale gradients close to the EDR exhibit significant oscillations at a similar frequency. Such oscillations are not expected for a crossing of a steady 2D EDR, and can be explained by a complex motion of the reconnection plane induced by current sheet kinking propagating in the out-of-reconnection-plane direction. Thus, all three spatial dimensions have to be taken into account to explain the observed perturbed EDR crossing. These results shed light on the interplay between magnetic reconnection and current sheet drift instabilities in electron-scale current sheets and highlight the need for adopting a 3D description of the EDR, going beyond the two-dimensional and steady-state conception of reconnection.

7.
J Vet Cardiol ; 37: 42-51, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34537674

RESUMO

OBJECTIVE: To evaluate owners' medication adherence for management of cardiovascular disease in the small animal specialty setting. ANIMALS, MATERIALS, AND METHODS: A questionnaire-based study of owners at a single, multispecialty, small animal referral center was conducted. Owners completed a written survey evaluating demographics, degree of medication adherence, and difficulties encountered for medication adherence. Owners were free to decline participation in the study. RESULTS: Ninety-six questionnaires were completed during the study period. Fifty-four respondents (56.3%) reported treating their pet for over one year for cardiovascular disease, and myxomatous mitral valve disease was the most common diagnosis (76.0%). Twenty-nine (30.2%) respondents felt they could consistently administer a maximum of three medications daily, and 46 (47.9%) respondents reported twice-daily dosing was the highest frequency of administration that could be consistently achieved. Twenty-two respondents (22.9%) reported that their pet required daily medications for at least one other chronic condition besides cardiac disease. Seventeen respondents (17.7%) reported at least occasionally missing medications, although only one (1.0%) reported it was more than 20% of medications per week. CONCLUSIONS: Medication adherence was high in this study population. Almost one-half of owners surveyed reported being unable to consistently administer more than three medications daily, and approximately one-quarter of patients were treated for at least one additional chronic condition requiring daily medications, in addition to cardiac disease. Clinicians should be aware of these factors when determining optimal treatment protocols for the management of cardiovascular disease in dogs.


Assuntos
Doenças Cardiovasculares , Doenças do Cão , Animais , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/veterinária , Doenças do Cão/tratamento farmacológico , Cães , Adesão à Medicação , Encaminhamento e Consulta , Inquéritos e Questionários
10.
J Small Anim Pract ; 62(9): 805-809, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33587292

RESUMO

OBJECTIVES: The purpose of this study was to investigate the frequency and perception of veterinary insurance among owners' at a small animal specialty hospital around a large urban city. MATERIALS AND METHODS: A questionnaire evaluated the prevalence and perception of insurance among owners at a small animal specialty hospital over a 2 month period. Respondents provided demographic information including age, sex, educational level and household income. Respondents without insurance were asked reasons for not having insurance, approximate cost of insurance per month desired and percentage of coverage of medical expenses they would want insurance to provide. Respondents with insurance were asked how they chose their current plan, how it affects their medical decisions for their pet and their overall satisfaction. RESULTS: Sixty-seven (28.5%) owners reporting having insurance for at least one pet. Owners most commonly selected their current insurance plan based on online research (27, 40.3%). Fifty-two respondents (77.6%) reported being satisfied with their insurance plan and 49 (73.2%) stated that would recommend their current insurance plan to a friend. CLINICAL SIGNIFICANCE: Insurance had a relatively high prevalence in this study group with most owners being satisfied with their current plan and would be likely to recommend it to a friend. The role of insurance in how it affects owner's medical decisions, care for their pet and interactions with veterinarians in companion animal medicine requires further evaluation.


Assuntos
Seguro , Médicos Veterinários , Animais , Atitude , Hospitais , Humanos , Inquéritos e Questionários
11.
Geophys Res Lett ; 47(13): e2020GL087574, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32999512

RESUMO

At the Earth's low-latitude magnetopause, clear signatures of the Kelvin-Helmholtz (KH) waves have been frequently observed during periods of the northward interplanetary magnetic field (IMF), whereas these signatures have been much less frequently observed during the southward IMF. Here, we performed the first 3-D fully kinetic simulation of the magnetopause KH instability under the southward IMF condition. The simulation demonstrates that fast magnetic reconnection is induced at multiple locations along the vortex edge in an early nonlinear growth phase of the instability. The reconnection outflow jets significantly disrupt the flow of the nonlinear KH vortex, while the disrupted turbulent flow strongly bends and twists the reconnected field lines. The resulting coupling of the complex field and flow patterns within the magnetopause boundary layer leads to a quick decay of the vortex structure, which may explain the difference in the observation probability of KH waves between northward and southward IMF conditions.

12.
Nat Commun ; 11(1): 5049, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028826

RESUMO

Magnetotail reconnection plays a crucial role in explosive energy conversion in geospace. Because of the lack of in-situ spacecraft observations, the onset mechanism of magnetotail reconnection, however, has been controversial for decades. The key question is whether magnetotail reconnection is externally driven to occur first on electron scales or spontaneously arising from an unstable configuration on ion scales. Here, we show, using spacecraft observations and particle-in-cell (PIC) simulations, that magnetotail reconnection starts from electron reconnection in the presence of a strong external driver. Our PIC simulations show that this electron reconnection then develops into ion reconnection. These results provide direct evidence for magnetotail reconnection onset caused by electron kinetics with a strong external driver.

13.
Phys Rev Lett ; 125(2): 025103, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32701350

RESUMO

We report measurements of lower-hybrid drift waves driving electron heating and vortical flows in an electron-scale reconnection layer under a guide field. Electrons accelerated by the electrostatic potential of the waves exhibit perpendicular and nongyrotropic heating. The vortical flows generate magnetic field perturbations comparable to the guide field magnitude. The measurements reveal a new regime of electron-wave interaction and how this interaction modifies the electron dynamics in the reconnection layer.

14.
Br J Surg ; 107(6): 705-711, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32077101

RESUMO

BACKGROUND: Oesophageal squamous cell carcinoma is an aggressive disease owing to early and widespread lymph node metastases. Multimodal therapy and radical surgery may improve prognosis. Few studies have investigated the efficacy of radical lymph node and thoracic duct resection. METHODS: Patients with oesophageal squamous cell carcinoma who underwent transthoracic minimally invasive oesophagectomy (TMIE) for cancer at Keio University Hospital between January 2004 and December 2016 were selected. Between 2004 and 2008, TMIE was performed in the lateral decubitus position without thoracic duct resection (standard TMIE). From 2009 onwards, TMIE with extended lymph node and thoracic duct resection was introduced (extended TMIE). Demographics, co-morbidity, number of retrieved lymph nodes, pathology, postoperative complications and recurrence-free survival (RFS) were compared between groups. RESULTS: Forty-four patients underwent standard TMIE and 191 extended TMIE. There were no significant differences in clinical and pathological tumour stage or postoperative complications. The extended-TMIE group had more lymph nodes removed at nodal stations 106recL and 112. Among patients with cT1 N0 disease, RFS was better in the extended-TMIE group (P < 0·001), whereas there was no difference in RFS between groups in patients with advanced disease. CONCLUSION: Extended TMIE including thoracic duct resection increased the number of lymph nodes retrieved and was associated with improved survival in patients with cT1 N0 oesophageal squamous cell carcinoma.


Assuntos
Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Esofagectomia/métodos , Excisão de Linfonodo/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ducto Torácico/cirurgia , Adulto , Idoso , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Análise de Sobrevida , Ducto Torácico/patologia , Resultado do Tratamento
15.
Phys Rev Lett ; 123(23): 235101, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868466

RESUMO

A 3D fully kinetic simulation shows that the lower-hybrid drift instability disturbs the front of magnetic reconnection outflow jets and additionally causes energy dissipation. The result is very consistent with a disturbance observed at the dipolarization front (DF) in Earth's magnetotail by the Magnetospheric Multiscale (MMS) mission. A fully kinetic dispersion relation solver, validated by the MMS observations, further predicts that the disturbance of the reconnection jet front could occur over different parameter regimes in space plasmas including Earth's DF and solar flares.

16.
J Comp Pathol ; 170: 53-59, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31375159

RESUMO

During the progression of chronic kidney disease (CKD), macrophage infiltration is a crucial event leading to tubulointerstitial fibrosis. In the present study, macrophages infiltrating renal tissue in dogs and cats with CKD were analysed immunohistochemically. Iba-1 was used as a pan-macrophage marker, CD204 was used as a marker of M2 macrophages and tumour necrosis factor (TNF)-α was used as a marker of M1 macrophages. Signals for Iba1 and CD204 were observed in the interstitium of all tested kidney samples. In dogs, the signals were diffusely scattered. In cats, both diffuse and focal signals were observed. Cells that were positive for Iba1 and CD204 were also observed in the tubular lumina in cats. Co-expression of Iba1 and CD204 was also observed in the infiltrating cells by immunofluorescence labelling, and these cells were negative for TNF-α. By quantitative analysis, the indices for Iba1- and CD204-positive cells were significantly correlated with the concentrations of plasma creatinine and/or urea and the extent of interstitial fibrosis in both dogs and cats. These results demonstrated that renal infiltration of M2 macrophages plays an important role in the progression of CKD in dogs and cats. The distribution pattern of the kidney-infiltrating macrophages was unique in cats and may be associated with a cat-specific renal fibrotic process.


Assuntos
Doenças do Gato/patologia , Doenças do Cão/patologia , Macrófagos/patologia , Insuficiência Renal Crônica/veterinária , Animais , Gatos , Cães
17.
J Small Anim Pract ; 60(9): 565-570, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31044427

RESUMO

OBJECTIVE: To determine the effect of atorvastatin on haemostatic parameters as measured by prothrombin time, activated partial thromboplastin time and thromboelastography in apparently healthy dogs administered 2 mg/kg orally once daily for 1 week. MATERIALS AND METHODS: Prospective study of 20 apparently healthy client-owned dogs at a small animal specialty hospital. Dogs had a baseline complete blood count, serum chemistry profile, fibrinogen, platelet count, prothrombin time, activated partial thromboplastin time and thromboelastography performed. Each dog was then administered approximately 2 mg/kg of atorvastatin orally once daily for 1 week, and the laboratory tests were repeated. Adverse effects attributed to atorvastatin were recorded. RESULTS: All 20 enrolled dogs completed the study. Dogs received a median dose of 2.06 mg/kg (range 1.94 to 2.44 mg/kg) atorvastatin once daily, which was associated with a significant increase in pulse rate, mean corpuscular haemoglobin concentration, albumin and a significant decrease in mean corpuscular volume, cholesterol and lipase values compared with baseline. On thromboelastography, there was a significant increase in maximum amplitude, G, coagulation index, amplitude at 30 minutes, amplitude at 60 minutes and significant decrease in percentage of clot lysed at 30 minutes and percentage of clot lysed at 60 minutes values compared with baseline. Six dogs had a noticeable increase in appetite. CLINICAL SIGNIFICANCE: The results of this study suggest that atorvastatin may produce a procoagulant effect in dogs, although the clinical significance is unclear. Polyphagia was the most commonly reported adverse effect.


Assuntos
Doenças do Cão , Hemostáticos , Animais , Atorvastatina , Cães , Estudos Prospectivos , Tempo de Protrombina/veterinária , Tromboelastografia/veterinária
18.
Phys Rev E ; 99(4-1): 043204, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31108651

RESUMO

The electron diffusion region (EDR) is the region where magnetic reconnection is initiated and electrons are energized. Because of experimental difficulties, the structure of the EDR is still poorly understood. A key question is whether the EDR has a homogeneous or patchy structure. Here we report Magnetospheric Multiscale (MMS) spacecraft observations providing evidence of inhomogeneous current densities and energy conversion over a few electron inertial lengths within an EDR at the terrestrial magnetopause, suggesting that the EDR can be rather structured. These inhomogenenities are revealed through multipoint measurements because the spacecraft separation is comparable to a few electron inertial lengths, allowing the entire MMS tetrahedron to be within the EDR most of the time. These observations are consistent with recent high-resolution and low-noise kinetic simulations.

19.
Oecologia ; 189(4): 971-980, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30919108

RESUMO

An important factor controlling tree species diversity is conspecific density dependence (CDD). Adult trees associated with arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM) can exhibit negative and positive CDD effects on conspecific recruitment, respectively. However, the extent to which these mycorrhizal associations affect spatial distributions of individual trees and their relative abundances within forests through CDD remains uncertain. We analysed changes in spatial correlations between adults and conspecific juveniles at different growth stages of five hardwood species in a 6-ha plot of an old-growth forest using a point pattern analysis. The clump sizes of large individuals were also evaluated using the Iδ index (a measure of individual dispersion) in 24 species. In two AM-associated species, juveniles were distributed at greater distances with increasing size or were always distributed at a distance from adults, resulting in small clumps of adults. In contrast, juveniles of two ECM-associated species were distributed close to adults during early or late growth stage, resulting in large clumps of adults. Juveniles of an ECM-associated species disappeared with increasing size, probably due to shade intolerance. In 24 tree species with large numbers of individuals within a plot, the relative basal area was related to both mycorrhizal type and maximum diameter, suggesting that the relative abundance of a species is largely related to its mycorrhizal associations and maximum plant size. This study strongly demonstrated that mycorrhizal associations play an important role in determining the spatial distribution patterns and community structure of tree species through CDD.


Assuntos
Micorrizas , Árvores , Florestas , Plantas
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