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1.
Rev Sci Instrum ; 92(5): 053543, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243308

RESUMO

Neutron-yield diagnostics at the NIF have been upgraded to include 48 detectors placed around the NIF target chamber to assess the DT-neutron-yield isotropy for inertial confinement fusion experiments. Real-time neutron-activation detectors are used to understand yield asymmetries due to Doppler shifts in the neutron energy attributed to hotspot motion, variations in the fuel and ablator areal densities, and other physics effects. In order to isolate target physics effects, we must understand the contribution due to neutron scattering associated with the different hardware configurations used for each experiment. We present results from several calibration experiments that demonstrate the ability to achieve our goal of 1% or better precision in determining the yield isotropy.

2.
Rev Sci Instrum ; 87(11): 11D821, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910447

RESUMO

The installation of a neutron imaging diagnostic with a polar view at the National Ignition Facility (NIF) required design of a new aperture, an extended pinhole array (PHA). This PHA is different from the pinhole array for the existing equatorial system due to significant changes in the alignment and recording systems. The complex set of component requirements, as well as significant space constraints in its intended location, makes the design of this aperture challenging. In addition, lessons learned from development of prior apertures mandate careful aperture metrology prior to first use. This paper discusses the PHA requirements, constraints, and the final design. The PHA design is complex due to size constraints, machining precision, assembly tolerances, and design requirements. When fully assembled, the aperture is a 15 mm × 15 mm × 200 mm tungsten and gold assembly. The PHA body is made from 2 layers of tungsten and 11 layers of gold. The gold layers include 4 layers containing penumbral openings, 4 layers containing pinholes and 3 spacer layers. In total, there are 64 individual, triangular pinholes with a field of view (FOV) of 200 µm and 6 penumbral apertures. Each pinhole is pointed to a slightly different location in the target plane, making the effective FOV of this PHA a 700 µm square in the target plane. The large FOV of the PHA reduces the alignment requirements both for the PHA and the target, allowing for alignment with a laser tracking system at NIF.

3.
Vet Rec ; 179(22): 572, 2016 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-27646049

RESUMO

The objective of this study was to determine the frequency of recommendation of adjuvant chemotherapy by UK-based general veterinary practitioners (GVPs) for canine patients with high-grade mast cell tumours (HGMCTs), splenic haemangiosarcomas (SHSs) and appendicular osteosarcomas (AOSs); to determine which chemotherapeutic protocols are used by GVPs; and to evaluate reasons why chemotherapy may or may not be recommended postoperatively. An internet survey was created in 2013 using an online programme and was distributed to GVPs. Questions relating to the use of adjuvant chemotherapy for three tumours were selected. In total, 300 responses were generated. Surgery was seen as primary therapy by most GVPs for HGMCT (91 per cent) and SHS (88 per cent), but less frequently for AOS (59 per cent). Also, 90, 40 and 57 per cent of respondents recommended adjuvant chemotherapy for HGMCT, SHS and AOS, respectively. Of these, an appropriate chemotherapy protocol was not known by 25, 51 and 36 per cent of GVPs for HGMCT, SHS and AOS, respectively. From the GVPs not recommending chemotherapy, 29, 64 and 66 per cent did not believe chemotherapy to be efficacious for these tumours. The frequency of recommendation regarding postoperative chemotherapy is variable by tumour type. Reasons given why postoperative chemotherapy is not recommended also vary by tumour type.


Assuntos
Atitude do Pessoal de Saúde , Doenças do Cão/tratamento farmacológico , Doenças do Cão/cirurgia , Médicos Veterinários/psicologia , Adulto , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Apêndice/tratamento farmacológico , Neoplasias do Apêndice/cirurgia , Neoplasias do Apêndice/veterinária , Quimioterapia Adjuvante , Cães , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/cirurgia , Hemangiossarcoma/veterinária , Humanos , Mastocitose/tratamento farmacológico , Mastocitose/patologia , Mastocitose/cirurgia , Mastocitose/veterinária , Pessoa de Meia-Idade , Gradação de Tumores , Osteossarcoma/tratamento farmacológico , Osteossarcoma/cirurgia , Osteossarcoma/veterinária , Neoplasias Esplênicas/tratamento farmacológico , Neoplasias Esplênicas/cirurgia , Neoplasias Esplênicas/veterinária , Inquéritos e Questionários , Reino Unido , Médicos Veterinários/estatística & dados numéricos
4.
Phys Rev Lett ; 106(8): 085004, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21405580

RESUMO

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 µm diameter hot core.

5.
Soc Psychiatry Psychiatr Epidemiol ; 34(2): 111-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10189818

RESUMO

Patient satisfaction can be a useful marker in evaluating the quality of psychiatric care. However, this form of measurement has been hampered by the lack of attention paid to the psychometric properties of instruments devised. The Psychiatric Care Satisfaction Questionnaire (PCSQ) was developed and tests of acceptability, validity and reliability were undertaken using 52 inpatients. Content validity was assessed by surveying psychiatrists, other mental health professionals, MIND workers and patient groups. Thirty-six (67.9%) of all mental health professionals felt that the questionnaire was a useful measure of patients' satisfaction with their care, and many comments also suggested high consensual validity. In terms of content validity, responses from patient groups indicated that the majority (63.6%) felt it to be a useful measure of patient satisfaction and 70.5% felt all the areas covered were important. Concurrent and criterion validity were also good, with high correlations with existing scales and with those on a section being significantly less satisfied on the PCSQ (F = 13.3, P = 0.0004). Test-retest reliability was adequate (Cohen's kappa 0.48-0.80) and the internal consistency of the PCSQ was good, at 0.82 (Cronbach's alpha). The PCSQ performed well in all aspects of validity and reliability, indicating that it has good psychometric properties and can be a useful tool for measuring patient satisfaction. However, there remains the need to analyse more closely the concept of satisfaction and its determinants.


Assuntos
Serviços de Saúde Mental/normas , Satisfação do Paciente , Inquéritos e Questionários , Humanos , Reprodutibilidade dos Testes , Reino Unido
6.
J Comp Neurol ; 393(2): 210-30, 1998 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-9548698

RESUMO

We have examined the development of parvalbumin immunoreactivity in the superior colliculi (SC) of the perinatal and mature rats and rabbits. In mature animals, parvalbumin-expressing cells (PECs) and neuropil in the retinorecipient layers were distributed in a continuous single band extending throughout the entire extent of the colliculus, whereas those in the intermediate layers formed distinct, radially oriented patches. Parvalbumin was expressed for the first time on postconceptional day 34 (PCD 34, postnatal day 12) and PCD 42 (postnatal day 11) in the SC of rat and rabbit, respectively. During ensuing development, both the thickness of the parvalbumin-expressing band in the retinorecipient layers and the numbers of PECs in this band gradually increased, reaching adultlike values by PCD 44 and PCD 50 in the rat and rabbit, respectively. In the rat, monocular eye enucleations on PCD 23 resulted in approximately 55% reduction in the number of PECs in the retinorecipient layers of the contralateral colliculi examined on PCD 44 or PCD 50. Unilateral ablations of the entire visual cortex on PCD 23 (before the first corticotectal fibers from visual cortices reach the SC) or on PCD 28 (when about half of the corticotectal fibers have reached colliculus) resulted in, respectively, approximately 55% and approximately 25% relative reduction in the number of PECs in the retinorecipient layers of the ipsilateral colliculi examined on PCD 44 or PCD 50. We conclude that the ontogenetic expression of parvalbumin in most of PECs in the retinorecipient collicular layers is induced by the activity of the contralateral retinotectal and/or the activity of the ipsilateral corticotectal afferents.


Assuntos
Parvalbuminas/biossíntese , Coelhos/fisiologia , Ratos Sprague-Dawley/fisiologia , Colículos Superiores/crescimento & desenvolvimento , Colículos Superiores/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Anticorpos Monoclonais , Proteínas de Ligação ao Cálcio/análise , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/imunologia , Denervação , Enucleação Ocular , Neurônios Aferentes/química , Parvalbuminas/análise , Parvalbuminas/imunologia , Ratos , Colículos Superiores/citologia , Córtex Visual/cirurgia
7.
J Comp Neurol ; 376(2): 223-40, 1996 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-8951639

RESUMO

Using an antibody against calbindin-28kD, we have studied the spatial pattern of expression of this protein in the superior colliculi (SC) of four strains of mature laboratory rats. In all four strains, calbindin-expressing cells (CECs) formed horizontally oriented tiers in the retinorecipient and intermediate gray layers but were diffusely distributed throughout the deep layers. Ontogenetically, calbindin-28kD was expressed for the first time in the retinorecipient layers at postconceptional day 20 (PCD 20), by cells located in the rostrolateral region where the first born retinal ganglion cells (RGCs) are represented. Although on the day of birth (PCD 22/23), the CECs were distributed more widely, they were still absent in the most medial part of the SC, that is, the region where the latest born RGCs are represented. The spatial distribution of CECs became adultlike only by PCD 29, that is, at the end of the period of the naturally occurring death of the RGCs. Monocular eye enucleations on PCD 23 prevented the expression of calbindin in the medial fifth of the retinorecipient layers of the contralateral SC, while the unilateral removal of the visual cortices had no discernable effect on the numbers and distribution of the CECs in either SC. Thus, the spatiotemporal pattern of ontogenetic expression of calbindin-28kD in the retinorecipient layers of SC reflects the spatiotemporal pattern of generation of the RGCs, and the retinal input appears to induce neuronal expression of calbindin-28kD in these layers.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteína G de Ligação ao Cálcio S100/biossíntese , Colículos Superiores/metabolismo , Animais , Animais Recém-Nascidos , Calbindinas , Tamanho Celular , Enucleação Ocular , Proteínas Fetais/biossíntese , Proteínas Fetais/genética , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Células Ganglionares da Retina/fisiologia , Proteína G de Ligação ao Cálcio S100/genética , Colículos Superiores/citologia , Colículos Superiores/embriologia , Colículos Superiores/crescimento & desenvolvimento , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Córtex Visual/lesões , Córtex Visual/fisiopatologia
8.
Br J Psychiatry ; 168(5): 641-6, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8733806

RESUMO

BACKGROUND: Measurement of the quality of psychiatric care including assessment of patients' views have become increasingly important as expectations of the standard of care rises. METHODS: Attitudes and satisfaction of acute psychiatric in-patients were investigated using a questionnaire looking at satisfaction, patients' views on personal and professional qualities of psychiatrists, empowerment and insight. RESULTS: The response rate was 79.2% (137 out of 173). Patients with a diagnosis of a non-affective psychotic illness, particularly those lacking insight were significantly less satisfied with their care. Respondents were more satisfied with the personal rather than the professional qualities of the doctors, and less satisfied with their empowerment and doctors' availability. CONCLUSIONS: In-patients' attitudes towards their psychiatric care involves a complex relationship between clinical and sociocultural characteristics. Satisfaction studies can serve as an important monitor and reminder of patient dissent.


Assuntos
Satisfação do Paciente , Relações Médico-Paciente , Psiquiatria , Transtornos Psicóticos/psicologia , Garantia da Qualidade dos Cuidados de Saúde , Adulto , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Internato e Residência , Londres , Masculino , Pessoa de Meia-Idade , Participação do Paciente , Poder Psicológico , Psiquiatria/educação , Transtornos Psicóticos/reabilitação
9.
Appl Opt ; 14(5): 1165-8, 1975 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20154790

RESUMO

The projection method of solving a set of linear equations was used to restore linearly degraded images. The advantages of this method are that it always converges, it can readily make use of a priori information about the image, and it does not need excessive computation time. Experimental results indicate that this method could potentially achieve superresolution.

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