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1.
Occup Med (Lond) ; 69(4): 251-257, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31049572

RESUMO

BACKGROUND: Despite the substantial personal and economic consequences of mental ill-health, and the relationship between mental ill-health and poor management provision, further work is needed to provide a robust evaluation of employment interventions to address mental ill-health in the workplace. AIMS: To provide a pilot service evaluation of a UK organization's mental health awareness for managers' training provision. METHODS: Participants were 93 employees at a UK-based organization who attended one of the three different types of, independently facilitated, half-day training courses designed to raise managers' awareness and understanding of mental health. All participants were asked to complete three questionnaires (one prior to the training session, one immediately following the training session and one 3 months after the training session). Each questionnaire contained six questions concerning participants' awareness of mental ill-health, and their confidence in dealing with mental ill-health among employees. RESULTS: Participants reported feeling more aware of mental ill-health at work and more confident in their ability to address mental ill-health among their employees after attending mental health awareness for managers' training. CONCLUSIONS: Although further work is needed to explore the efficacy of different types of training, the results of our pilot evaluation alongside the extant literature suggest that workplace interventions can have positive implications for good mental health.


Assuntos
Transtornos Mentais , Saúde Ocupacional/educação , Gestão de Recursos Humanos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Projetos Piloto , Inquéritos e Questionários , Reino Unido
2.
Phys Rev Lett ; 120(20): 204801, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29864368

RESUMO

A dual ion species plasma expansion scheme from a novel target structure is introduced, in which a nanometer-thick layer of pure deuterium exists as a buffer species at the target-vacuum interface of a hydrogen plasma. Modeling shows that by controlling the deuterium layer thickness, a composite H^{+}/D^{+} ion beam can be produced by target normal sheath acceleration (TNSA), with an adjustable ratio of ion densities, as high energy proton acceleration is suppressed by the acceleration of a spectrally peaked deuteron beam. Particle in cell modeling shows that a (4.3±0.7) MeV per nucleon deuteron beam is accelerated, in a directional cone of half angle 9°. Experimentally, this was investigated using state of the art cryogenic targetry and a spectrally peaked deuteron beam of (3.4±0.7) MeV per nucleon was measured in a cone of half angle 7°-9°, while maintaining a significant TNSA proton component.

3.
Proc Biol Sci ; 284(1857)2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28637860

RESUMO

To sample information optimally, sensory systems must adapt to the ecological demands of each animal species. These adaptations can occur peripherally, in the anatomical structures of sensory organs and their receptors; and centrally, as higher-order neural processing in the brain. While a rich body of investigations has focused on peripheral adaptations, our understanding is sparse when it comes to central mechanisms. We quantified how peripheral adaptations in the eyes, and central adaptations in the wide-field motion vision system, set the trade-off between resolution and sensitivity in three species of hawkmoths active at very different light levels: nocturnal Deilephila elpenor, crepuscular Manduca sexta, and diurnal Macroglossum stellatarum. Using optical measurements and physiological recordings from the photoreceptors and wide-field motion neurons in the lobula complex, we demonstrate that all three species use spatial and temporal summation to improve visual performance in dim light. The diurnal Macroglossum relies least on summation, but can only see at brighter intensities. Manduca, with large sensitive eyes, relies less on neural summation than the smaller eyed Deilephila, but both species attain similar visual performance at nocturnal light levels. Our results reveal how the visual systems of these three hawkmoth species are intimately matched to their visual ecologies.


Assuntos
Olho , Mariposas/fisiologia , Neurônios/fisiologia , Visão Ocular , Animais , Luz , Fenômenos Fisiológicos Oculares
4.
Geosynth Int ; 24(2): 184-197, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28740357

RESUMO

The new applications for carbon nanotubes (CNTs) in various fields and consequently their greater production volume have increased their potential release to the environment. Landfills are one of the major locations where carbon nanotubes are expected to be disposed and it is important to ensure that they can limit the release of CNTs. Diffusion of multiwall carbon nanotubes (MWCNTs) dispersed in an aqueous media through a high-density polyethylene (HDPE) geomembrane (as a part of the landfill barrier system) was examined. Based on the laboratory tests, the permeation coefficient was estimated to be less than 5.1×10-15 m2/s. The potential performance of a HDPE geomembrane and geosynthetic clay liner (GCL) as parts of a composite liner in containing MWCNTs was modelled for six different scenarios. The results suggest that the low value of permeation coefficient of an HDPE geomembrane makes it an effective diffusive barrier for MWCNTs and by keeping the geomembrane defects to minimum during the construction (e.g., number of holes and length of wrinkles) a composite liner commonly used in municipal solid waste landfills will effectively contain MWCNTs.

5.
Phys Rev Lett ; 113(18): 185001, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25396375

RESUMO

The influence of lattice-melt-induced resistivity gradients on the transport of mega-ampere currents of fast electrons in solids is investigated numerically and experimentally using laser-accelerated protons to induce isochoric heating. Tailoring the heating profile enables the resistive magnetic fields which strongly influence the current propagation to be manipulated. This tunable laser-driven process enables important fast electron beam properties, including the beam divergence, profile, and symmetry to be actively tailored, and without recourse to complex target manufacture.

6.
J Dairy Sci ; 97(3): 1782-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24418279

RESUMO

The objective of this clinical trial was to compare conception and newborn calf sex ratios among Jersey heifers and lactating cows inseminated with either standard sex-sorted semen (low-dose, high-sort; LDHS) containing 2.1 × 10(6) sorted sperm at 90% purity or high-dose, low-sort (HDLS) semen containing 10 × 10(6) sorted sperm at 75% purity. After a specified voluntary waiting period (VWP), female subjects, consisting of nulliparous heifers (VWP 10 mo of age) and lactating cows (VWP 50d in milk), received their first service and were systematically allocated to each treatment group in the order in which they presented for artificial insemination (AI). Females were bred to the same sire and type of sex-sorted semen for up to 2 additional services. Animals that were not pregnant after 3 breeding attempts were excluded. A total of 1,846 services were performed on 1,011 eligible females (LDHS; n=494, HDLS; n=517), which consisted of 516 nulliparous heifers and 495 lactating cows. Study groups were comparable with respect to the mean age at first AI for nulliparous heifers and the mean days in milk at first AI for parous cows. Insemination with HDLS semen did not result in a higher proportion of pregnancies per AI (P/AI) compared with LDHS semen for either nulliparous heifers (P/AI=43 vs. 38%) or parous cows (P/AI=47 vs. 43%). Insemination of nulliparous heifers using HDLS resulted in a lower proportion of newborn female calves compared with those bred to LDHS (76% vs. 87%). Similarly, lactating cows bred to HDLS gave birth to a lower proportion of newborn female calves compared with those bred to LDHS (79 vs. 90%). The odds ratio for a female calf to be born to an animal inseminated with HDLS compared with LDHS was 0.32 for nulliparous heifers and 0.19 for parous cows. Overall, the use of HDLS resulted in fewer females compared with LDHS, which may be explained by the lower concentration of X-bearing spermatozoa in HDLS compared with LDHS.


Assuntos
Bovinos , Indústria de Laticínios/métodos , Fertilização , Sêmen/fisiologia , Razão de Masculinidade , Espermatozoides/fisiologia , Animais , California , Feminino , Lactação , Modelos Logísticos , Masculino
7.
Eur J Drug Metab Pharmacokinet ; 39(2): 139-46, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23797843

RESUMO

The 8-aminoquinoline drug primaquine (PQ) is currently the only drug in use against the persistent malaria caused by the hypnozoite-forming strains P. vivax and P. ovale. However, despite decades of research, its complete metabolic profile is still poorly understood. In the present study, the metabolism of PQ was evaluated by incubating the drug with pooled human hepatocytes cultured in vitro as well as with recombinant cytochrome P450 (CYP) iso- enzymes, monoamine oxidases (MAO), and flavin-containing monooxygenases (FMO). Targeted LC-MS/MS analysis of hepatocyte incubations using chemical inhibitors indicated that PQ was predominantly metabolized by CYPs 3A4, 1A2 and 2D6, MAO-A, -B and FMO-3. Confirmation of these results was sought by incubation of PQ with the corresponding recombinant enzymes. Small amounts of carboxyprimaquine (CPQ), the major observed PQ metabolite in vivo, were detected in recombinant MAO-A incubations along with another peak at m/z 261, and no significant formation of CPQ with any other recombinant enzymes was observed. Incubations with all recombinant enzymes identified as potentially active towards PQ from the hepatocyte-based assay resulted in significant parent loss over the course of 1 h. These results suggest that several enzymes, including CYPs in combination with FMOs and MAOs, play a role in the overall metabolism of PQ and indicate a major role for MAO-A. Future studies to elucidate the potential role in cytotoxicity and/or efficacy of the PQ metabolite observed at m/z 261, as observed in MAO-A isoenzyme studies, are needed.


Assuntos
Antimaláricos/metabolismo , Hepatócitos/metabolismo , Primaquina/metabolismo , Células Cultivadas , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
8.
Toxicon ; : 107825, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908526

RESUMO

Mushroom poisonings are common in the United States. Gyromitrin (acetaldehyde N-methyl-N-formylhydrazone) is a clinically significant mycotoxin primarily associated with the lorchel (i.e. the false morel) Gyromitra esculenta. Resemblance between 'true and false morels' has resulted in misidentification of Gyromitra spp. as edible and sought after Morchella spp., resulting in toxicity. Despite literature evidence outlining toxic sequalae, Gyromitra spp. mushrooms are commonly consumed and prepared for culinary purposes. Classic clinical teachings emphasize significant neurotoxicity, including seizures, associated with ingestion of gyromitrin-containing mushrooms, stemming from gyromitrin's terminal metabolite monomethylhydrazine. We performed a longitudinal descriptive review of the clinical toxicity associated with ingestion of mushroom species known or suspected to contain gyromitrin in cases reported to the Michigan Poison & Drug Information Center between January 1, 2002, to December 31, 2020. Our 19-year descriptive case series of gyromitrin-containing mushroom ingestions reported to our Center demonstrated a preponderance of gastrointestinal signs and symptoms, including hepatotoxicity. Of 118 identified cases, 108 (91.5%) of the reported ingestions involved Gyromitra esculenta. The most frequent clinical findings associated with symptomatic ingestions (n= 83) were the aforementioned gastrointestinal symptoms (n=62; 74.7%). Neurological symptoms were less frequent (n=22, 26.5%) while hepatotoxicity occurred in fewer patients (n=14; 16.9%). Of symptomatic patients, most were treated with symptomatic and supportive care (n=58; 70%). Pyridoxine was used in a total of seven patients (n=7; 8.4%) with either hepatotoxicity or neurotoxicity. Medical outcomes ranged from minor to major, with no reported deaths. Patient presentations (i.e. GI vs. neurotoxic symptoms) following ingestion of gyromitrin-containing mushrooms may be highly variable and multifactorial, owing to differences in dose ingested, geographical distribution, genetic variability of both patient and mushroom species, and species-specific differences in toxin composition. Future research warrants species-level identification of ingested gyromitrin-containing mushrooms and investigating the contribution of genetic polymorphisms to differences in clinical toxidromes.

9.
Phys Rev Lett ; 111(9): 095001, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-24033041

RESUMO

Fast electron transport in Si, driven by ultraintense laser pulses, is investigated experimentally and via 3D hybrid particle-in-cell simulations. A transition from a Gaussian-like to an annular fast electron beam profile is demonstrated and explained by resistively generated magnetic fields. The results highlight the potential to completely transform the beam transport pattern by tailoring the resistivity-temperature profile at temperatures as low as a few eV.

10.
ScientificWorldJournal ; 2013: 357341, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24391460

RESUMO

Sixty-four looked after and accommodated males aged 13-16 had an assessment of their quality of life using Paediatric Quality of Life Inventory (PedsQL) and Quality of Life in Care (QOLIC). The participants were from a Scottish residential centre for young people with severe emotional and behavioural difficulties. The total sample of 64 participants consists of two distinct groups: residential group (n = 33) and a secure care group (n = 31). Over 3 observations the aim of the study was to identify similarities and differences between the groups and to establish the sensitivity of the PedsQL and the PedsQL in care module (QOLIC) as a measurement instrument for Quality of Life (QoL) in adolescent males. Overall there was a nonsignificant increase in the quality of life of these young people at the centre as measured by PedsQL and QOLIC over 3 observations. No significant differences were detected in the quality of life scores between the two groups using the QOLIC.


Assuntos
Sintomas Afetivos/psicologia , Transtornos Mentais/psicologia , Qualidade de Vida/psicologia , Instituições Residenciais/estatística & dados numéricos , Adolescente , Sintomas Afetivos/epidemiologia , Comorbidade , Humanos , Masculino , Transtornos Mentais/epidemiologia , Prevalência , Fatores de Risco , Escócia
11.
J Virol ; 85(15): 7683-98, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21632764

RESUMO

The 2003 monkeypox virus (MPXV) outbreak and subsequent laboratory studies demonstrated that the black-tailed prairie dog is susceptible to MPXV infection and that the ensuing rash illness is similar to human systemic orthopoxvirus (OPXV) infection, including a 7- to 9-day incubation period and, likely, in some cases a respiratory route of infection; these features distinguish this model from others. The need for safe and efficacious vaccines for OPVX in areas where it is endemic or epidemic is important to protect an increasingly OPXV-naïve population. In this study, we tested current and investigational smallpox vaccines for safety, induction of anti-OPXV antibodies, and protection against mortality and morbidity in two MPXV challenges. None of the smallpox vaccines caused illness in this model, and all vaccinated animals showed anti-OPXV antibody responses and neutralizing antibody. We tested vaccine efficacy by challenging the animals with 10(5) or 10(6) PFU Congo Basin MPXV 30 days postvaccination and evaluating morbidity and mortality. Our results demonstrated that vaccination with either Dryvax or Acambis2000 protected the animals from death with no rash illness. Vaccination with IMVAMUNE also protected the animals from death, albeit with (modified) rash illness. Based on the results of this study, we believe prairie dogs offer a novel and potentially useful small animal model for the safety and efficacy testing of smallpox vaccines in pre- and postexposure vaccine testing, which is important for public health planning.


Assuntos
Modelos Animais , Monkeypox virus/imunologia , Vacina Antivariólica/imunologia , Animais , DNA Viral/sangue , Relação Dose-Resposta Imunológica , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Monkeypox virus/genética , Testes de Neutralização , Sciuridae , Vacina Antivariólica/administração & dosagem
12.
Opt Lett ; 37(9): 1409-11, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22555687

RESUMO

The authors report the development of an electric oxygen-iodine laser with higher output using a larger product of gain and gain length, g0L. A factor of 4.4 increase in laser power output on the 1315 nm atomic iodine transition was achieved with a factor of 3 increase in gain length. I(2P1/2) is pumped using energy transferred from O2(a1Δ) produced by flowing a gas mixture of O2-He-NO through three coaxial geometry radio-frequency discharges. Continuous wave (CW) average total laser power of 481 W was extracted with g0L=0.042.

13.
Nat Commun ; 13(1): 518, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35082304

RESUMO

Urban greening can potentially help mitigate heat-related mortality and flooding facing the >4 billion urban population worldwide. However, the geographical variation of the relative combined hydrological and thermal performance benefits of such interventions are unknown. Here we quantify globally, using a hydrological model, how climate-driven trade-offs exist between hydrological retention and cooling potential of urban greening such as green roofs and parks. Using a Budyko framework, we show that water retention generally increases with aridity in water-limited environments, while cooling potential favors energy-limited climates. Our models suggest that common urban greening strategies cannot yield high performance simultaneously for addressing both urban heat-island and urban flooding problems in most cities globally. Irrigation, if sustainable, may enhance cooling while maintaining retention performance in more arid locations. Increased precipitation variability with climate change may reduce performance of thinner green-infrastructure more quickly compared to greened areas with thicker soils and root systems. Our results provide a conceptual framework and first-order quantitative guide for urban development, renewal and policymaking.

14.
Sci Rep ; 12(1): 1910, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115579

RESUMO

Increasing the intensity to which high power laser pulses are focused has opened up new research possibilities, including promising new approaches to particle acceleration and phenomena such as high field quantum electrodynamics. Whilst the intensity achievable with a laser pulse of a given power can be increased via tighter focusing, the focal spot profile also plays an important role in the interaction physics. Here we show that the spatial-intensity distribution, and specifically the ratio of the intensity in the peak of the laser focal spot to the halo surrounding it, is important in the interaction of ultraintense laser pulses with solid targets. By comparing proton acceleration measurements from foil targets irradiated with by a near-diffraction-limited wavelength scale focal spot and larger F-number focusing, we find that this spatial-intensity contrast parameter strongly influences laser energy coupling to fast electrons. We find that for multi-petawatt pulses, spatial-intensity contrast is potentially as important as temporal-intensity contrast.

15.
Phys Rev Lett ; 106(22): 225003, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21702607

RESUMO

By using a thick (250 µm) target with 350 µm radius of curvature, the intense proton beam driven by a petawatt laser is focused at a distance of ∼1 mm from the target for all detectable energies up to ∼25 MeV. The thickness of the foil facilitates beam focusing as it suppresses the dynamic evolution of the beam divergence caused by peaked electron flux distribution at the target rear side. In addition, reduction in inherent beam divergence due to the target thickness relaxes the curvature requirement for short-range focusing. Energy resolved mapping of the proton beam trajectories from mesh radiographs infers the focusing and the data agree with a simple geometrical modeling based on ballistic beam propagation.

16.
Phys Rev Lett ; 106(18): 185004, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21635098

RESUMO

The effect of lattice structure on the transport of energetic (MeV) electrons in solids irradiated by ultraintense laser pulses is investigated using various allotropes of carbon. We observe smooth electron transport in diamond, whereas beam filamentation is observed with less ordered forms of carbon. The highly ordered lattice structure of diamond is shown to result in a transient state of warm dense carbon with metalliclike conductivity, at temperatures of the order of 1-100 eV, leading to suppression of electron beam filamentation.

17.
Phys Rev Lett ; 105(19): 195008, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21231179

RESUMO

The use of two separate ultraintense laser pulses in laser-proton acceleration was compared to the single pulse case employing the same total laser energy. A double pulse profile, with the temporal separation of the pulses varied between 0.75-2.5 ps, was shown to result in an increased maximum proton energy and an increase in conversion efficiency to fast protons by up to a factor of 3.3. Particle-in-cell simulations indicate the existence of a two stage acceleration process. The second phase, induced by the main pulse preferentially accelerates slower protons located deeper in the plasma, in contrast to conventional target normal sheath acceleration.

18.
J Cell Biol ; 138(6): 1303-11, 1997 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-9298985

RESUMO

Although inositol trisphosphate (IP3) functions in releasing Ca2+ in eggs at fertilization, it is not known how fertilization activates the phospholipase C that produces IP3. To distinguish between a role for PLCgamma, which is activated when its two src homology-2 (SH2) domains bind to an activated tyrosine kinase, and PLCbeta, which is activated by a G protein, we injected starfish eggs with a PLCgamma SH2 domain fusion protein that inhibits activation of PLCgamma. In these eggs, Ca2+ release at fertilization was delayed, or with a high concentration of protein and a low concentration of sperm, completely inhibited. The PLCgammaSH2 protein is a specific inhibitor of PLCgamma in the egg, since it did not inhibit PLCbeta activation of Ca2+ release initiated by the serotonin 2c receptor, or activation of Ca2+ release by IP3 injection. Furthermore, injection of a PLCgamma SH2 domain protein mutated at its phosphotyrosine binding site, or the SH2 domains of another protein (the phosphatase SHP2), did not inhibit Ca2+ release at fertilization. These results indicate that during fertilization of starfish eggs, activation of phospholipase Cgamma by an SH2 domain-mediated process stimulates the production of IP3 that causes intracellular Ca2+ release.


Assuntos
Cálcio/metabolismo , Isoenzimas/metabolismo , Interações Espermatozoide-Óvulo/fisiologia , Estrelas-do-Mar/fisiologia , Fosfolipases Tipo C/metabolismo , Animais , Feminino , Glutationa Transferase/química , Glutationa Transferase/farmacologia , Masculino , Microinjeções , Oócitos/citologia , Oócitos/enzimologia , Fosfolipase C gama , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Sensibilidade e Especificidade , Transdução de Sinais/fisiologia , Domínios de Homologia de src/fisiologia
19.
Science ; 201(4360): 1020-3, 1978 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-684422

RESUMO

The flame retardant, tris(2,3-dibromopropyl)phosphate (tris-BP), which is a mutagen and causes cancer and sterility in animals is absorbed from fabric by people. 2,3-Dibromopropanol, a metboloite of tris-BP and a mutagen itself, has been found in the urine samples of ten children who were wearing or who had worn tris-BP-treated sleepwear. Eight of these children were wearing well-washed sleepwear and the possibility of absorption of tris-BP from well-washed sleepwear discussed. 2,3-Dibromopropanol was not found in the urines of one child and one adult who had never worn tris-BP-treated garments.


Assuntos
Vestuário , Retardadores de Chama/metabolismo , Mutagênicos/metabolismo , Organofosfatos/metabolismo , Propanóis , Absorção Cutânea , 1-Propanol/urina , Criança , Cromatografia Gasosa , Feminino , Humanos , Hidrocarbonetos Bromados/metabolismo , Espectrometria de Massas/métodos
20.
Neuron ; 28(2): 595-606, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11144367

RESUMO

In many species, including humans, exposure to high image velocities induces motion adaptation, but the neural mechanisms are unclear. We have isolated two mechanisms that act on directionally selective motion-sensitive neurons in the fly's visual system. Both are driven strongly by movement and weakly, if at all, by flicker. The first mechanism, a subtractive process, is directional and is only activated by stimuli that excite the neuron. The second, a reduction in contrast gain, is strongly recruited by motion in any direction, even if the adapting stimulus does not excite the cell. These mechanisms are well designed to operate effectively within the context of motion coding. They can prevent saturation at susceptible nonlinear stages in processing, cope with rapid changes in direction, and preserve fine structure within receptive fields.


Assuntos
Adaptação Fisiológica/fisiologia , Sensibilidades de Contraste/fisiologia , Dípteros/fisiologia , Percepção de Movimento/fisiologia , Neurônios/fisiologia , Animais , Olho/inervação , Fusão Flicker/fisiologia , Técnicas In Vitro , Potenciais da Membrana/fisiologia , Estimulação Luminosa , Limiar Sensorial/fisiologia
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