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1.
Genomics ; 115(6): 110723, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804957

RESUMO

Allopolyploids often experience subgenome dominance, with one subgenome showing higher levels of gene expression and greater gene retention. Here, we address the functionality of both subgenomes of allotetraploid common carp (Cyprinus carpio) by analysing a functional network of interferon-stimulated genes (ISGs) crucial in anti-viral immune defence. As an indicator of subgenome dominance we investigated retainment of a core set of ohnologous ISGs. To facilitate our functional genomic analysis a high quality genome was assembled (WagV4.0). Transcriptome data from an in vitro experiment mimicking a viral infection was used to infer ISG expression. Transcriptome analysis confirmed induction of 88 ISG ohnologs on both subgenomes. In both control and infected states, average expression of ISG ohnologs was comparable between the two subgenomes. Also, the highest expressing and most inducible gene copies of an ohnolog pair could be derived from either subgenome. We found no strong evidence of subgenome dominance for common carp.


Assuntos
Carpas , Genoma de Planta , Animais , Humanos , Tetraploidia , Carpas/genética , Duplicação Gênica , Perfilação da Expressão Gênica
2.
Transfus Clin Biol ; 29(3): 198-204, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35987531

RESUMO

OBJECTIVE: Gay, bisexual and other men who have sex with men (gbMSM) were ineligible to donate blood in most countries since the 1980's. In Canada the deferral period has been incrementally decreased from lifetime to male-to-male sex in the last 3 months. Now a few countries have removed the deferral altogether. Risk models have been utilised to estimate the probability of an HIV positive donation being released into the blood supply and to inform incremental changes to the length of the deferral period. Here we use public health data to estimate the risk of HIV if the gbMSM deferral criteria were removed in Canada. MATERIAL AND METHODS: We calculate the risk reduction among heterosexuals based on responses to standard risk questions routinely asked of donors. We assume gbMSM will donate at the same rate as heterosexual males. We apply the same risk reduction principle to HIV incidence and prevalence among gbMSM in the general population to evaluate the HIV risk without gbMSM time deferral. We model three scenarios where risk reduction is varied by assumptions about incidence and compliance with deferral criteria. RESULTS: The estimates for all scenarios were not significantly different to the currently observed scenario which predicts a residual risk of 0.02 HIV positive per million donations (95% CI: 0.000006-0.09). CONCLUSION: The models predict that removing the gbMSM deferral criteria would result in HIV residual risk similar to currently observed.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Doadores de Sangue , Canadá/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Vigilância em Saúde Pública
3.
Phys Rev Lett ; 124(15): 153203, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32357057

RESUMO

We demonstrate a novel method for coherent optical manipulation of individual nuclear spins in the solid state, mediated by the electronic states of a proximal quantum emitter. Specifically, using the nitrogen-vacancy (NV) color center in diamond, we demonstrate control of a proximal ^{14}N nuclear spin via an all-optical Raman technique. We evaluate the extent to which the intrinsic physical properties of the NV center limit the performance of coherent control, and we find that it is ultimately constrained by the relative rates of transverse hyperfine coupling and radiative decay in the NV center's excited state. Possible extensions and applications to other color centers are discussed.

4.
Phys Rev Lett ; 125(26): 265102, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449730

RESUMO

Magnetic reconnection is of fundamental importance to plasmas because of its role in releasing and repartitioning stored magnetic energy. Previous results suggest that this energy is predominantly released as ion enthalpy flux along the reconnection outflow. Using Magnetospheric Multiscale data we find the existence of very significant electron energy flux densities in the vicinity of the magnetopause electron dissipation region, orthogonal to the ion energy outflow. These may significantly impact models of electron transport, wave generation, and particle acceleration.

5.
J Magn Reson ; 286: 138-142, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29241045

RESUMO

Recently, it was observed that protons in non-conducting solids doped with 1,3-bisdiphenylene-2-phenylallyl (BDPA) or its sulfonated derivative (SA-BDPA) can be polarized through Overhauser effects via resonant microwave irradiation. These effects were present under magic angle spinning conditions in magnetic fields between 5 and 18.8 T and at temperatures near 100 K. This communication reports similar effects in static samples at 6.7 T and, more importantly, at temperatures as low as 1.2 K, in a different dynamic regime than in the previous study. Our results provide new information towards understanding the mechanism of the Overhauser effect in non-conducting solids. We discuss possible origins of the fluctuations that can give rise to an Overhauser effect at such low temperatures.

6.
Vox Sang ; 113(2): 95-103, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29238993

RESUMO

We review the history and evolution of blood donor criteria for men who have sex with men (MSM). Deferral policies in many jurisdictions, including Australia, New Zealand, Canada, the United States, Brazil and many western European countries are based on a period of abstinence from MSM, often of 12 months duration. Several countries (Italy, Spain and Portugal) defer donors based on sexual behaviours considered to be at high risk, regardless of whether the partner is same sex or opposite sex. Compliance is a key determinant in the efficacy of any deferral policy. We summarize research themes and strategies discussed at a January 2017 meeting held in Toronto, Canada, to provide an evidence basis for future policy changes.


Assuntos
Bancos de Sangue/normas , Doadores de Sangue , Segurança do Sangue/normas , Homossexualidade Masculina , Segurança do Sangue/tendências , Coleta de Amostras Sanguíneas/normas , Canadá , Congressos como Assunto , Humanos , Masculino
7.
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.

9.
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.

10.
Science ; 352(6290): aaf2939, 2016 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-27174677

RESUMO

Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.

11.
Vox Sang ; 110(2): 185-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26361365

RESUMO

Standard definitions of donor reactions allow each blood establishment to monitor donor adverse events and compare with other organizations to develop best practices. The ISBT Haemovigilance Working Party leads a multi-organizational effort to update the 2008 ISBT standard for surveillance of complications related to blood donation. Revised definitions have been developed and endorsed by the ISBT, AABB, International Haemovigilance Network (IHN) and other international organizations.


Assuntos
Doadores de Sangue/classificação , Segurança do Sangue/normas , Guias como Assunto , Terminologia como Assunto , Reação Transfusional/classificação , Doadores de Sangue/estatística & dados numéricos , Segurança do Sangue/métodos , Humanos , Cooperação Internacional , Sociedades Médicas , Reação Transfusional/epidemiologia
12.
Proc Natl Acad Sci U S A ; 113(17): 4579-84, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-19887640

RESUMO

We developed a "continual engagement" model to better integrate knowledge from policy makers, communities, and researchers with the goal of promoting more effective action to balance poverty alleviation and wildlife conservation in 4 pastoral ecosystems of East Africa. The model involved the creation of a core boundary-spanning team, including community facilitators, a policy facilitator, and transdisciplinary researchers, responsible for linking with a wide range of actors from local to global scales. Collaborative researcher-facilitator community teams integrated local and scientific knowledge to help communities and policy makers improve herd quality and health, expand biodiversity payment schemes, develop land-use plans, and fully engage together in pastoral and wildlife policy development. This model focused on the creation of hybrid scientific-local knowledge highly relevant to community and policy maker needs. The facilitation team learned to be more effective by focusing on noncontroversial livelihood issues before addressing more difficult wildlife issues, using strategic and periodic engagement with most partners instead of continual engagement, and reducing costs by providing new scientific information only when deemed essential. We conclude by examining the role of facilitation in redressing asymmetries in power in researcher-community-policy maker teams, the role of individual values and character in establishing trust, and how to sustain knowledge-action links when project funding ends.


Assuntos
Conservação dos Recursos Naturais , Pradaria , Modelos Teóricos , Formulação de Políticas , África Oriental , Agricultura , Animais , Animais Selvagens , Comportamento Cooperativo , Humanos , Pesquisadores , Características de Residência
14.
Vox Sang ; 109(4): 336-42, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25976025

RESUMO

BACKGROUND AND OBJECTIVES: Mandatory predonation reading materials inform donors about risk factors for transmissible disease, possible complications of donation and changes to the donation process. We aimed to assess the attention to predonation reading materials and factors which may affect attention. MATERIALS AND METHODS: A national survey in 2008 of 18,108 blood donors asked about self-assessed attention to reading the materials. In face-to-face interviews, 441 donors completed additional questions about reading the materials and a literacy test. Qualitative interviews of 27 donors assessed their approach to reading. RESULTS: In the national survey, most of the first-time donors said they read all or most of the materials (90.9% first-time vs. 57.6% repeat donors, P < 0.001) and 66% vs. 23.1% reported reading them carefully (P < 0.001). In face-to-face interviews comparing those who read materials carefully, skimmed or did not read, most knew that donors are informed of positive transmissible disease test results (97.1%, 95.5, 98.0 P > 0.05), but fewer recalled seeing the definition of sex (77.2%, 56.9, 24.2 P < 0.001). Literacy was poor (30.5% frustration level, 60.3% instructional, 9.2% independent) but similar when those who read materials carefully, skimmed or did not read were compared (P > 0.05). Qualitative interviews showed that donors are reluctant to read any more than necessary and decide based on perceived importance or relevance. CONCLUSION: Attention to predonation reading materials tends to be better among first-time donors. The effectiveness is limited by low motivation to read, especially for repeat donors, as well as poor literacy.


Assuntos
Doadores de Sangue/educação , Leitura , Adulto , Atenção , Doadores de Sangue/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Phys Rev Lett ; 114(14): 145502, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25910136

RESUMO

We report direct measurement of population dynamics in the excited state manifold of a nitrogen-vacancy (NV) center in diamond. We quantify the phonon-induced mixing rate and demonstrate that it can be completely suppressed at low temperatures. Further, we measure the intersystem crossing (ISC) rate for different excited states and develop a theoretical model that unifies the phonon-induced mixing and ISC mechanisms. We find that our model is in excellent agreement with experiment and that it can be used to predict unknown elements of the NV center's electronic structure. We discuss the model's implications for enhancing the NV center's performance as a room-temperature sensor.

16.
Minerva Urol Nefrol ; 67(2): 97-102, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25847867

RESUMO

AIM: Acute renal injury may occur after amphotericin B (AmB) administration. The hypothesized injury mechanism is renal vasoconstriction and direct toxic damage. Hyperbaric oxygen therapy (HBO) is indicated for treatment of many ischemic events but not for acute renal failure (ARF). The aim of this study was to investigate the role of HBO therapy in AmB induced ARF. METHODS: ARF was induced in 41 Sprague-Dawley rats by a single dose of 75 mg/kg AmB. The rats were randomly divided into two groups; one group was treated with daily HBO for 3 consecutive days. The control group received no HBO treatment. Parameters of renal function were taken on the 5th day after AmB administration. RESULTS: Forty-one rats were treated with AmB, 21 received HBO and 20 served as controls. Body weight loss following the administration of AmB was 13.5+14.7% in the HBO treated rats, as opposed to 24.6+5% in the control group (P=0.004). Serum creatinine and urea were 0.49+0.13 mg/dL and 200.63+87.82 mg/dL in the treatment group and 0.70+0.22 mg/dL and 368.01+169.35 mg/dL, respectively in the control (P=0.001). CONCLUSION: In this model of AmB-induced ARF, HBO treatment alleviated renal injury as reflected by changes in serum creatinine and urea levels.


Assuntos
Injúria Renal Aguda/terapia , Anfotericina B , Antibacterianos , Oxigenoterapia Hiperbárica , Injúria Renal Aguda/sangue , Injúria Renal Aguda/etiologia , Animais , Biomarcadores/sangue , Creatinina/sangue , Modelos Animais de Doenças , Oxigenoterapia Hiperbárica/métodos , Testes de Função Renal , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ureia/sangue , Redução de Peso/efeitos dos fármacos
17.
Vox Sang ; 106(4): 372-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24877223

RESUMO

Canada now allows donations from men who had sex with men (MSM) if their last sexual contact with a man was more than 5 years ago. We modelled the impact of this policy on supply and safety. Approximately 4500 new donors will be added and assuming compliance to the new policy remains unchanged, the worst-case scenario predicts the introduction of one HIV-contaminated unit in the inventory every 1072 years. This change will entail negligible additional HIV risk to recipients. A five-year deferral will also protect recipients against the theoretical concern that MSM may represent a group at higher risk of sexually transmitted, emerging blood borne pathogens.


Assuntos
Doadores de Sangue/legislação & jurisprudência , Segurança do Sangue , Comportamento Sexual , Adulto , Doadores de Sangue/ética , Transfusão de Sangue , Canadá , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Risco
18.
Phys Rev Lett ; 112(14): 145002, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24765977

RESUMO

Kinetic simulations of magnetotail reconnection have revealed electromagnetic whistlers originating near the exhaust boundary and propagating into the inflow region. The whistler production mechanism is not a linear instability, but rather is Cerenkov emission of almost parallel whistlers from localized moving clumps of charge (finite-size quasiparticles) associated with nonlinear coherent electron phase space holes. Whistlers are strongly excited by holes without ever growing exponentially. In the simulation the whistlers are emitted in the source region from holes that accelerate down the magnetic separatrix towards the x line. The phase velocity of the whistlers vφ in the source region is everywhere well matched to the hole velocity vH as required by the Cerenkov condition. The simulation shows emission is most efficient near the theoretical maximum vφ=half the electron Alfven speed, consistent with the new theoretical prediction that faster holes radiate more efficiently. While transferring energy to whistlers the holes lose coherence and dissipate over a few local ion inertial lengths. The whistlers, however, propagate to the x line and out over many 10's of ion inertial lengths into the inflow region of reconnection. As the whistlers pass near the x line they modulate the rate at which magnetic field lines reconnect.

19.
Thorax ; 69(5): 443-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24595666

RESUMO

BACKGROUND: Although respiratory symptoms are characteristic features of COPD, there is no standardised method for quantifying their severity in stable disease. OBJECTIVE: To evaluate the EXACT-Respiratory Symptom (E-RS) measure, a daily diary comprising 11 of the 14 items in the Exacerbations of Chronic Pulmonary Disease Tool (EXACT). METHODS: Qualitative: patient focus group and interviews to address content validity. Quantitative: secondary data analyses to test reliability and validity. RESULTS: Qualitative: n=84; mean (SD) age 65 (10) years, FEV1 1.2(0.4) L; 44% male. Subject descriptions of their respiratory symptoms were consistent with E-RS content and structure. Quantitative: n=188; mean (SD) age 66 (10) years, FEV1 1.2(0.5) L; 50% male. Factor analysis (FA) showed 3 subscales: RS-Breathlessness, RS-Cough & Sputum, and RS-Chest Symptoms; second-order FA supported a general factor and total score. Reliability (total and subscales): 0.88, 0.86, 0.73, 0.81; 2-day test-retest ICC: 0.90, 0.86, 0.87, 0.82, respectively. VALIDITY: Total scores correlated significantly (p < 0.0001) with SGRQ Total (r=0.75), Symptoms (r=0.66), Activity (r=0.57), Impact (r=0.70) scores; subscale correlations were also significant (r=0.26, p < 0.05 (RS-Chest Symptoms with Activity) to r=0.69, p < 0.0001 (RS-Cough & Sputum with Symptoms). RS-Breathlessness correlated with rescue medication use (r=0.32, p < 0.0001), clinician-reported mMRC (r=0.33, p < 0.0001), and FEV1% predicted (r=-0.17, p < 0.05). E-RS scores differentiated groups based on chronic bronchitis diagnosis (p < 0.01-0.001), smoking status (p < 0.05-0.001), and rescue medication use (p < 0.05-0.0001). CONCLUSIONS: Results suggest the RS-Total is a reliable and valid instrument for evaluating respiratory symptom severity in stable COPD. Further study of sensitivity to change is warranted.


Assuntos
Tosse/diagnóstico , Coleta de Dados/normas , Dispneia/diagnóstico , Indicadores Básicos de Saúde , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Inquéritos e Questionários , Idoso , Tosse/etiologia , Tosse/fisiopatologia , Dispneia/etiologia , Dispneia/fisiopatologia , Feminino , Seguimentos , Volume Expiratório Forçado , Humanos , Masculino , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
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