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1.
J Sleep Res ; : e14010, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37621222

RESUMO

Mornings are salient times for disrupted affect that may be impacted by prior sleep. The current study extends work linking sleep disruptions with negative affect by examining how nightly changes in sleep duration, timing, and quality relative to a person's average impact morning affect. We further tested whether depression severity moderated the relationship between nightly variations in sleep and morning affect. This is a secondary analysis of participants ages 18-65 years with varying levels of depression (N = 91) who wore an Actiwatch for 3-17 days (n = 73) while reporting morning affect using a visual analogue scale. Multilevel models tested the previous night's sleep duration, timing, or quality as a predictor of morning affect. Sleep measures were group-mean centred to account for nightly variation in participants' sleep. A cross-level interaction between depression severity and nightly sleep was entered. Sleeping longer (b = 0.1; p < 0.001) and later (b = 1.8; p = 0.01) than usual were both associated with better morning mood. There was a significant interaction between nightly actigraphic sleep duration and depression severity on morning affect (b = 0.003; p = 0.003). Participants with higher depression severity reported worse affect upon waking after sleeping less than their usual. In comparison, sleeping less than usual did not affect morning affect ratings for participants with lower depression. A similar interaction was found for sleep quality (b = 0.02; p < 0.001). There was no interaction for midsleep timing. Sleeping less than usual impacted morning affect in individuals with greater depression, potentially suggesting a pathway by which sleep disturbances perpetuate depression.

2.
Psychol Med ; 43(10): 2215-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23286303

RESUMO

BACKGROUND: Sleep loss produces abnormal increases in reward seeking but the mechanisms underlying this phenomenon are poorly understood. The present study examined the influence of one night of sleep deprivation on neural responses to a monetary reward task in a sample of late adolescents/young adults. METHOD: Using a within-subjects crossover design, 27 healthy, right-handed late adolescents/young adults (16 females, 11 males; mean age 23.1 years) underwent functional magnetic resonance imaging (fMRI) following a night of sleep deprivation and following a night of normal sleep. Participants' recent sleep history was monitored using actigraphy for 1 week prior to each sleep condition. RESULTS: Following sleep deprivation, participants exhibited increased activity in the ventral striatum (VS) and reduced deactivation in the medial prefrontal cortex (mPFC) during the winning of monetary reward, relative to the same task following normal sleep conditions. Shorter total sleep time over the five nights before the sleep-deprived testing condition was associated with reduced deactivation in the mPFC during reward. CONCLUSIONS: These findings support the hypothesis that sleep loss produces aberrant functioning in reward neural circuitry, increasing the salience of positively reinforcing stimuli. Aberrant reward functioning related to insufficient sleep may contribute to the development and maintenance of reward dysfunction-related disorders, such as compulsive gambling, eating, substance abuse and mood disorders.


Assuntos
Corpo Estriado/fisiopatologia , Neuroimagem Funcional/métodos , Córtex Pré-Frontal/fisiopatologia , Recompensa , Privação do Sono/fisiopatologia , Sono/fisiologia , Actigrafia , Adolescente , Adulto , Corpo Estriado/fisiologia , Estudos Cross-Over , Feminino , Neuroimagem Funcional/instrumentação , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/fisiologia , Adulto Jovem
3.
Science ; 264(5155): 101-4, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8140412

RESUMO

Transforming growth factor-beta (TGF-beta) and activin exert their effects by binding to heteromeric complexes of type I and type II receptors. The type II receptors for TGF-beta and activin are transmembrane serine-threonine kinases; a series of related receptors, denoted activin receptor-like kinase (ALK) 1 to 5, have recently been identified, and ALK-6 is described here. ALK-5 has been shown to be a functional TGF-beta type I receptor. A systematic analysis revealed that most ALKs formed heteromeric complexes with the type II receptors for TGF-beta and activin after overexpression in COS cells; however, among the six ALKs, only ALK-5 was a functional TGF-beta type I receptor for activation of plasminogen activator inhibitor-1, and only ALK-2 and ALK-4 bound activin with high affinity.


Assuntos
Inibinas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Receptores de Ativinas , Ativinas , Sequência de Aminoácidos , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I , Linhagem Celular , Ligantes , Camundongos , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases/química , Receptores de Fatores de Crescimento/química , Receptores de Fatores de Crescimento Transformadores beta/química
4.
J Vet Intern Med ; 23(3): 636-42, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19645847

RESUMO

BACKGROUND: Anaplasma phagocytophilum infects several mammalian species, and can persist in sheep, dogs, and calves. However, whether this organism persists in horses or induces long-term clinical abnormalities is not known. OBJECTIVES: To evaluate whether A. phagocytophilum can persist in horses and to document clinical findings for 3 months after complete recovery from acute disease. ANIMALS: Five clinically normal adult horses that had recovered spontaneously from experimentally induced acute disease caused by a Swedish equine isolate of A. phagocytophilum. METHODS: Horses were monitored for up to 129 days post inoculation (PI) by daily clinical examination and at least alternate day blood sampling for evidence of A. phagocytophilum on polymerase chain reaction (PCR) and blood smears. All horses were euthanized and underwent postmortem examination. RESULTS: All horses were periodically PCR positive after recovery from acute infection. Before day 66 PI 2 horses were persistently PCR negative whereas 3 horses were intermittently PCR positive. Subsequently, 4 of 5 horses were intermittently PCR positive, particularly after stress mimicking interventions. One animal was positive immediately before postmortem examination. Clinical abnormalities related to persistence of anaplasma were not observed. No specific changes were found at postmortem examination, and all sampled tissues from all horses were negative on PCR for A. phagocytophilum. CONCLUSIONS AND CLINICAL IMPORTANCE: Infection with A. phagocytophilum can persist in the horse for at least 129 days. However, the continued presence of the organism is not associated with detectable clinical or pathological abnormalities.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Anaplasmose/microbiologia , Doenças dos Cavalos/microbiologia , Animais , Doença Crônica , DNA Bacteriano/isolamento & purificação , Cavalos , Técnicas de Diagnóstico Molecular
5.
Rev Sci Instrum ; 79(2 Pt 2): 02C108, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315234

RESUMO

IPP Garching is heavily involved in the development of the rf driven H(-)/D(-) ion source for the ITER NBI. After the successful demonstration of the required physical parameters, the experimental conditions have been extended to long pulses and large area beam extraction. This paper contains descriptions of the source and power supply modifications necessitated for long pulses as well as the latest results including the first 1 h pulse. Suppression of the coextracted electron current is a key issue. Experiments with potential control, different magnetic filter fields, and cesium handling to suppress the electrons and stabilize the currents are also reported.

6.
Rev Sci Instrum ; 79(2 Pt 2): 02A511, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315132

RESUMO

The international fusion experiment ITER requires for the plasma heating and current drive a neutral beam injection system based on negative hydrogen ion sources at 0.3 Pa. The ion source must deliver a current of 40 A D(-) for up to 1 h with an accelerated current density of 200 Am/(2) and a ratio of coextracted electrons to ions below 1. The extraction area is 0.2 m(2) from an aperture array with an envelope of 1.5 x 0.6 m(2). A high power rf-driven negative ion source has been successfully developed at the Max-Planck Institute for Plasma Physics (IPP) at three test facilities in parallel. Current densities of 330 and 230 Am/(2) have been achieved for hydrogen and deuterium, respectively, at a pressure of 0.3 Pa and an electron/ion ratio below 1 for a small extraction area (0.007 m(2)) and short pulses (<4 s). In the long pulse experiment, equipped with an extraction area of 0.02 m(2), the pulse length has been extended to 3600 s. A large rf source, with the width and half the height of the ITER source but without extraction system, is intended to demonstrate the size scaling and plasma homogeneity of rf ion sources. The source operates routinely now. First results on plasma homogeneity obtained from optical emission spectroscopy and Langmuir probes are very promising. Based on the success of the IPP development program, the high power rf-driven negative ion source has been chosen recently for the ITER beam systems in the ITER design review process.

7.
Vet Rec ; 160(4): 122-5, 2007 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-17259454

RESUMO

A 19-year-old horse that was one of a group of six horses infected experimentally with Anaplasma phagocytophilum for a study of the pathogenesis of equine granulocytic ehrlichiosis died suddenly two days after first showing clinical signs of disease. The clinical signs and laboratory findings observed before its death were similar to all those of the other infected horses, and to previous reports of this disease. A postmortem examination revealed widespread haemorrhaging in its internal organs, and vasculitis and thrombosis in the kidneys. These changes are consistent with disseminated intravascular coagulation, which has previously been reported in human beings infected with the presumably identical agent of human granulocytic ehrlichiosis.


Assuntos
Anaplasma phagocytophilum/patogenicidade , Ehrlichiose/veterinária , Doenças dos Cavalos/microbiologia , Animais , Ehrlichiose/microbiologia , Cavalos , Masculino
8.
Sleep Health ; 2(2): 167-174, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27525300

RESUMO

OBJECTIVES: We conducted a pilot study of a sleep health promotion program for college students. The aims of the study were to 1) determine the feasibility of the program, and 2) explore changes in sleep knowledge and sleep diary parameters. DESIGN: Open trial of a sleep health promotion program for college students. SETTING: A small liberal arts university in southwestern Pennsylvania. PARTICIPANTS: University students (primarily female). INTERVENTION: Active intervention components included individualized email feedback based on each participant's baseline sleep diary and an in-person, group format presentation on sleep health. MEASUREMENTS: Participants completed online questionnaires and sleep diaries before and after the health promotion intervention. Online questionnaires focused on sleep knowledge and attitudes toward sleep, as well as Patient Reported Outcomes Measurement Information System (PROMIS) sleep and psychosocial assessments. RESULTS: Of participants who completed some aspect of the study, 89% completed at least one intervention component (in-person lecture and/or sleep diary). Participants reported significant improvement in sleep knowledge and changes in sleep diary parameters (decreased sleep onset latency and time spent in bed, resulting in greater sleep efficiency). Sleep duration also increased by 30 minutes among short sleepers who obtained <7 hours sleep at baseline. CONCLUSIONS: Preliminary evaluation of a brief program to promote sleep health suggests that it is feasible and acceptable to implement, and that it can favorably alter sleep knowledge and behaviors reported on the sleep diary in college students. Controlled trials are warranted.

9.
Oncogene ; 8(10): 2879-87, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8397373

RESUMO

Human cDNA clones encoding four novel putative transmembrane protein serine/threonine kinases, denoted activin receptor-like kinase (ALK) -1, -2, -3 and -4, were obtained using a polymerase chain reaction (PCR)-based strategy. The PCR primers were designed based upon the sequence similarity between the activin receptor type II and Daf-1. The cDNA clones for ALK-1, -2 and -3 encode complete proteins of 503, 509 and 532 amino acids respectively. The ALK-4 cDNA is incomplete and the predicted protein of 383 amino acids has a truncated extracellular domain. The ALKs share similar domain structures, comprising predicted signal sequences at the N-terminals, followed by hydrophilic cysteine-rich ligand-binding domains, single hydrophobic transmembrane regions and C-terminal intracellular portions that consist almost entirely of putative serine/threonine kinase domains. The ALKs have approximately 40% sequence identity to activin receptors type II and IIB, transforming growth factor-beta (TGF-beta) type II receptor and Daf-1 in the kinase domains. However, the sequence identities are higher (60-79%) between ALK-1, -2, -3 and -4, suggesting that they form a subfamily among the putative receptor serine/threonine kinases. The extracellular domains of ALKs show only little sequence identity to other putative receptor serine/threonine kinases, but the cysteine residues are conserved. Their structural properties suggest that ALK-1 to -4 are receptors that may bind ligands that are members of the TGF-beta superfamily. The expression of mRNA in human tissues varied for the different ALKs; ALK-2 and ALK-4 showed ubiquitous tissue expression patterns, whereas the distribution of ALK-1 and ALK-3 varied strongly between different tissues with more restricted expression patterns. These results suggest that each ALK may have different in vivo functions.


Assuntos
Proteínas Serina-Treonina Quinases/isolamento & purificação , Receptores de Superfície Celular/isolamento & purificação , Receptores de Ativinas , Sequência de Aminoácidos , Sequência de Bases , Receptores de Proteínas Morfogenéticas Ósseas Tipo I , Códon/química , Códon/genética , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Receptores de Superfície Celular/genética , Análise de Sequência de DNA
10.
J Vet Intern Med ; 19(2): 232-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15822569

RESUMO

Six horses were experimentally infected by administration of horse blood containing a Swedish strain of Anaplasma phagocytophilum. The polymerase chain reaction (PCR) signal was consistently detected 2-3 days before appearance of clinical signs and persisted 4-9 days beyond abatement of clinical signs, whereas diagnostic inclusion bodies were 1st noted on average 2.6 +/- 1.5 (SD) days after onset of fever. Clinical signs and hematologic changes were largely indistinguishable from those previously reported for diseases caused by A phagocytophilum (formerly Ehrlichia equi--"Californian agent") and the human-derived human granulocytic ehrlichiosis agent. Horses 1st demonstrated antibody response 12-16 days after inoculation, 2 cases of which were still febrile, and serotiters rapidly peaked within 3-7 days of clinical illness. One horse died during the acute stage of disease, but initial clinical signs and hematologic changes were similar to those of other infected horses. This report shows that, despite minor genetic differences, a European equine-derived strain of A. phagocytophilum may be similar in pathogenicity to the Californian agent. The PCR used holds promise to widen the diagnostic window and would also be diagnostic during the initial days of clinical disease when inclusions in neutrophils in blood smears are not yet apparent.


Assuntos
Anaplasma phagocytophilum , Ehrlichiose/veterinária , Doenças dos Cavalos/fisiopatologia , Anaplasma phagocytophilum/imunologia , Anaplasma phagocytophilum/isolamento & purificação , Animais , Anticorpos Antibacterianos/sangue , Contagem de Células Sanguíneas/veterinária , Temperatura Corporal , Ehrlichiose/sangue , Ehrlichiose/imunologia , Ehrlichiose/fisiopatologia , Doenças dos Cavalos/sangue , Doenças dos Cavalos/imunologia , Cavalos , Reação em Cadeia da Polimerase/veterinária
11.
Neuropsychologia ; 29(7): 695-702, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1944871

RESUMO

Regional cerebral blood flow (rCBF) was assessed by means of HMPAO-SPECT in two experimental groups. In a control condition both groups listened to abstract words, in the experimental condition they heard five names of objects. One group was advised to form visual images of the objects, the other group was advised to form acoustic images of the sounds made by these objects. Post-experimental questionnaires revealed that most of the subjects in the acoustic imagery condition had had visual images in addition to the acoustic ones. Both imagery conditions lead to approximately equal increases of rCBF in the left inferior occipital region and in the left thalamus. Flow increases in both hippocampal regions and the right inferior and superior temporal regions were larger in the acoustic than in the visual imagery condition. It is concluded that only the activation of left inferior occipital and left thalamic regions can be interpreted as being related to modality-specific visual aspects of imagery.


Assuntos
Circulação Cerebrovascular/fisiologia , Imaginação/fisiologia , Lobo Occipital/fisiologia , Lobo Temporal/fisiologia , Percepção Auditiva/fisiologia , Feminino , Hipocampo/fisiologia , Humanos , Masculino , Inquéritos e Questionários , Tálamo/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único , Percepção Visual/fisiologia
12.
Immunol Lett ; 41(1): 59-66, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7959904

RESUMO

In a total of 22 failing hearts from human transplant recipients, the expression of major histocompatibility complex (MHC) molecules, the CD phenotype of infiltrating mononuclear cells, and the number of fibroblasts were analyzed by immunohistochemistry. Compared with 10 non-failing control hearts, significantly higher morphometric area fractions of HLA-ABC and HLA-DR with a concomitant increase of CD3-, CD4- and CD8-positive cells were found to be comparable in 12 patients with idiopathic dilated cardiomyopathy and in 10 patients with secondary heart failure. Furthermore, the similarity of T-cell activation in idiopathic and secondary variants of the disease were substantiated by the following observations: (1) the site-specific distribution of MHC molecules and mononuclear cells in the myocardium was comparable in idiopathic and secondary dilated cardiomyopathy; (2) 6 individuals with lymphocytic aggregates in their myocardium in association with the highest levels of HLA-ABC expression were equally distributed among idiopathic and secondary patient subsets; and (3) expression of HLA-ABC and HLA-DR correlated with that of an endothelial cell marker, von Willebrand factor, in failing myocardia of both study groups. In conclusion, no difference was found in increased MHC molecule expression in failing myocardium of idiopathic and secondary variants of dilated cardiomyopathy, and these entities were not differentially associated with infiltration by increased numbers of T lymphocytes. Hence, we postulate that these immunopathological features are consequences rather than causative factors of myocardial degeneration and dilatation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Cardiomiopatia Dilatada/imunologia , Endocárdio/imunologia , Antígenos HLA/biossíntese , Miocárdio/imunologia , Cardiomiopatia Hipertrófica/imunologia , Feminino , Fibroblastos/imunologia , Transplante de Coração , Humanos , Técnicas Imunoenzimáticas , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
13.
Am J Cardiol ; 75(14): 913-8, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7733000

RESUMO

Circulating levels of extracellular matrix components were measured by radioimmunoassays and tested if they were useful for clinical staging in chronic heart failure. In 41 patients with dilated cardiomyopathy (33 idiopathic and 8 ischemic cases), the serum concentrations of procollagen type III aminoterminal peptide (PIIINP), type I collagen telopeptide (ICTP), and basement membrane laminin were significantly higher than in 30 healthy controls regardless of the underlying etiology. Patients with serum values of PIIINP, ICTP, and laminin > 7 micrograms/L, 7.6 micrograms/L, and 2.3 U/ml, respectively, were at higher relative risk for advanced clinical stage, poor hemodynamic condition, hyponatremia, heart transplantation, and death during follow-up than patients with low levels, with the exception that serum laminin > 2.3 U/ml was not significantly associated with hyponatremia and heart transplantation. Despite their interdependence on liver function, circulating levels of PIIINP and ICTP were independent predictors of mortality. In 17 of the 41 patients with cardiomyopathy whose explanted hearts were available for histologic evaluation, serum PIIINP, ICTP, and laminin significantly correlated with the myocardial area fractions of their tissue analogues (PIIINP vs myocardial collagen type III, r = 0.784, p = 0.0013; serum ICTP vs myocardial collagen type I, r = 0.603, p = 0.0527; and serum laminin vs myocardial laminin, r = 0.605, p = 0.0411). In conclusion, the increase in extracellular matrix turnover, which may partially be derived from fibrosis in the myocardium, can be measured in the serum of patients with dilated cardiomyopathy, and has an impact on risk stratification and prognosis.


Assuntos
Cardiomiopatia Dilatada/sangue , Matriz Extracelular/metabolismo , Cardiomiopatia Dilatada/classificação , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/mortalidade , Colágeno/análise , Colágeno/sangue , Colágeno Tipo I , Feminino , Fibrose/sangue , Fibrose/diagnóstico , Seguimentos , Humanos , Laminina/análise , Laminina/sangue , Masculino , Pessoa de Meia-Idade , Miocárdio/química , Miocárdio/patologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Prognóstico , Risco , Taxa de Sobrevida
14.
Neurosci Lett ; 124(2): 256-9, 1991 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2067724

RESUMO

In early blind mammals, the deprived visual cortex undergoes anatomical and functional alterations. Its functional role was investigated in the early human blind by using patterns of cortical activation as measured by scalp-recorded event-related slow negative DC potential shifts. The blind showed higher occipital negativity than did sighted persons both during a tactile reading task and a non-reading tactile control task. Results point to a possible role for the blind's visual cortex in tactile processes.


Assuntos
Cegueira/fisiopatologia , Córtex Cerebral/fisiopatologia , Lobo Occipital/fisiopatologia , Visão Ocular/fisiologia , Adulto , Eletrofisiologia , Feminino , Humanos , Masculino , Tato/fisiologia
15.
Neurosci Lett ; 150(2): 162-4, 1993 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-8469415

RESUMO

Cerebral flow indices were measured in 7 early blind and 13 sighted persons twice, during a task of passive and of active touch. In the blind, inferior occipital and cerebellar indices were higher. But they were not significantly modified by the kind of tactile task.


Assuntos
Cegueira/fisiopatologia , Cerebelo/irrigação sanguínea , Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Lobo Occipital/irrigação sanguínea , Adulto , Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Feminino , Glucose/metabolismo , Humanos , Masculino , Lobo Occipital/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único
16.
Prev Vet Med ; 49(3-4): 191-208, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11311953

RESUMO

A cross-sectional study of the seroprevalence to Borrelia burgdorferi sensu lato and granulocytic Ehrlichia spp. in Swedish horses was conducted to evaluate associations with demographic, clinical and tick-exposure factors. From September 1997-1998, blood samples from 2018 horses were collected from the animals presented to veterinary clinics affiliated with the Swedish Horserace Totalizator Board (regardless of the primary cause for consultation). Standardized questionnaires with information both from owners and attending veterinarians accompanied each blood sample. The apparent seroprevalences to B. burgdorferi s. l. and granulocytic Ehrlichia spp. were 16.8 and 16.7%, respectively. The northern region had the lowest seroprevalences. Four logistic models were developed (controlling for demographic variables). In the disease model of seropositivity to B. burgdorferi s. l., age, breed, geographic region, the serologic titer to granulocytic Ehrlichia spp., season and the diagnosis coffin-joint arthritis were significant. In the tick-exposure model of B. burgdorferi s. l., pasture access the previous year and gender were significant. Age, racing activity, geographic region, season and the serologic titer to B. burgdorferi s. l. were associated with positivity to granulocytic Ehrlichia spp. In the tick-exposure model of granulocytic Ehrlichia spp., pasture access was a risk factor. An interaction between racing activity and geographic region showed that the risk of positive serologic reactions to Ehrlichia spp. was increased in the horse population in the south and middle of Sweden, but only among horses not used for racing. Except for the positive association between coffin-joint arthritis and serologic reactions to B. burgdorferi s. l., there were no significant associations in the multivariable models between non-specific or specific clinical sign or disease with seropositivity to either of these agents.


Assuntos
Grupo Borrelia Burgdorferi/imunologia , Ehrlichia/imunologia , Ehrlichiose/veterinária , Doenças dos Cavalos/epidemiologia , Doença de Lyme/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Animais , Anticorpos Antibacterianos/sangue , Estudos Transversais , Demografia , Ehrlichiose/epidemiologia , Ehrlichiose/imunologia , Feminino , Doenças dos Cavalos/imunologia , Doenças dos Cavalos/microbiologia , Cavalos , Doença de Lyme/epidemiologia , Doença de Lyme/imunologia , Masculino , Estações do Ano , Estudos Soroepidemiológicos , Suécia/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/imunologia , Carrapatos
17.
Rev Sci Instrum ; 85(2): 02B305, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593582

RESUMO

An important step in the European R&D roadmap towards the neutral beam heating systems of ITER is the new test facility ELISE (Extraction from a Large Ion Source Experiment) for large-scale extraction from a half-size ITER RF source. The test facility was constructed in the last years at Max-Planck-Institut für Plasmaphysik Garching and is now operational. ELISE is gaining early experience of the performance and operation of large RF-driven negative hydrogen ion sources with plasma illumination of a source area of 1 × 0.9 m(2) and an extraction area of 0.1 m(2) using 640 apertures. First results in volume operation, i.e., without caesium seeding, are presented.

18.
Rev Sci Instrum ; 85(2): 02B301, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593578

RESUMO

Decreasing the co-extracted electron current while simultaneously keeping negative ion (NI) current sufficiently high is a crucial issue on the development plasma source system for ITER Neutral Beam Injector. To support finding the best extraction conditions the 3D Particle-in-Cell Monte Carlo Collision electrostatic code ONIX (Orsay Negative Ion eXtraction) has been developed. Close collaboration with experiments and other numerical models allows performing realistic simulations with relevant input parameters: plasma properties, geometry of the extraction aperture, full 3D magnetic field map, etc. For the first time ONIX has been benchmarked with commercial positive ions tracing code KOBRA3D. A very good agreement in terms of the meniscus position and depth has been found. Simulation of NI extraction with different e/NI ratio in bulk plasma shows high relevance of the direct negative ion extraction from the surface produced NI in order to obtain extracted NI current as in the experimental results from BATMAN testbed.

19.
Rev Sci Instrum ; 85(11): 11D864, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430277

RESUMO

Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understand neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes.

20.
Rev Sci Instrum ; 85(2): 02A736, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593470

RESUMO

The Source for Production of Ion of Deuterium Extracted from Rf plasma (SPIDER) test facility is under construction in Padova to optimise the operation of the beam source of ITER neutral beam injectors. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon-fibre-carbon-composite tiles. A small-scale version of the entire system has been employed in the BAvarian Test MAchine for Negative ions (BATMAN) testbed by arranging two prototype tiles in the vertical direction. The paper presents a description of the mini-STRIKE system and of the data analysis procedures, as well as some results concerning the BATMAN beam under varying operating conditions.

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