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1.
Rev Sci Instrum ; 94(2): 023507, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859040

RESUMEN

The PROBIES diagnostic is a new, highly flexible, imaging and energy spectrometer designed for laser-accelerated protons. The diagnostic can detect low-mode spatial variations in the proton beam profile while resolving multiple energies on a single detector or more. When a radiochromic film stack is employed for "single-shot mode," the energy resolution of the stack can be greatly increased while reducing the need for large numbers of films; for example, a recently deployed version allowed for 180 unique energy measurements spanning ∼3 to 75 MeV with <0.4 MeV resolution using just 20 films vs 180 for a comparable traditional film and filter stack. When utilized with a scintillator, the diagnostic can be run in high-rep-rate (>Hz rate) mode to recover nine proton energy bins. We also demonstrate a deep learning-based method to analyze data from synthetic PROBIES images with greater than 95% accuracy on sub-millisecond timescales and retrained with experimental data to analyze real-world images on sub-millisecond time-scales with comparable accuracy.

2.
Phys Rev E ; 101(3-1): 031201, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32289929

RESUMEN

Relativistic electron temperatures were measured from kilojoule, subrelativistic laser-plasma interactions. Experiments show an order of magnitude higher temperatures than expected from a ponderomotive scaling, where temperatures of up to 2.2 MeV were generated using an intensity of 1×10^{18}W/cm^{2}. Two-dimensional particle-in-cell simulations suggest that electrons gain superponderomotive energies by stochastic acceleration as they sample a large area of rapidly changing laser phase. We demonstrate that such high temperatures are possible from subrelativistic intensities by using lasers with long pulse durations and large spatial scales.

3.
Healthc Manage Forum ; 30(2): 107-110, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28929892

RESUMEN

The model established at Orillia Soldiers Memorial Hospital involves family physicians as the most responsible physician. They act as "admission gatekeeper" for all unattached patients who are admitted to the psychiatry in-patient unit. A PubMed, EBSCO, OVID Medline, Embase, CINAHL, and Web of Science database review of the last 10 years (2006-2016) was undertaken. A satisfaction survey was undertaken. An intensive literature review found this model to be unique. The model has proved to be extremely efficient and cost-effective.


Asunto(s)
Modelos Organizacionales , Servicio de Psiquiatría en Hospital/organización & administración , Análisis Costo-Beneficio , Médicos Hospitalarios/organización & administración , Humanos , Tiempo de Internación , Ontario , Satisfacción del Paciente , Servicio de Psiquiatría en Hospital/economía , Servicio de Psiquiatría en Hospital/normas
4.
Neuroscience ; 290: 31-40, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25595994

RESUMEN

Anesthetic doses of ketamine induce apoptosis, as well as gene expression of activity-dependent neuroprotective protein (ADNP), a putative homeodomain transcription factor in rat pups (P7). This study investigated if ketamine induced ADNP protein in a dose-dependent manner in vitro and in vivo using primary cultures of cortical neurons and neonatal pups (P7). In vivo immunohistochemistry demonstrated a sub-anesthetic dose of ketamine increased ADNP in the somatosensory cortex (SCC) which was previously identified to be damaged by repeated exposure to anesthetic doses of ketamine. Administration of low-dose ketamine prior to full sedation prevented caspase-3 activation in the hippocampus and SCC. Primary cultures of cortical neurons treated with ketamine (10 µM-10mM) at 3 days-in vitro (3 DIV) displayed a concentration-dependent decrease in expanded growth cones. Furthermore, neuronal production and localization of ADNP varied as a function of both ketamine concentration and length of exposure. Taken together, these data support the model that ADNP induction may be partially responsible for the efficacy of a low-dose ketamine pre-treatment in preventing ketamine-induced neuronal cell death.


Asunto(s)
Ketamina/farmacología , Proteínas del Tejido Nervioso/metabolismo , Neuronas/efectos de los fármacos , Neuronas/fisiología , Fármacos Neuroprotectores/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Western Blotting , Caspasa 3/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Conos de Crecimiento/efectos de los fármacos , Conos de Crecimiento/patología , Conos de Crecimiento/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/patología , Hipocampo/fisiología , Inmunohistoquímica , Neuronas/patología , Ratas Sprague-Dawley , Corteza Somatosensorial/efectos de los fármacos , Corteza Somatosensorial/patología , Corteza Somatosensorial/fisiología
5.
Rev Sci Instrum ; 85(10): 103504, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25362390

RESUMEN

A compact, step range filter proton spectrometer has been developed for the measurement of the absolute DD proton spectrum, from which yield and areal density (ρR) are inferred for deuterium-filled thin-shell inertial confinement fusion implosions. This spectrometer, which is based on tantalum step-range filters, is sensitive to protons in the energy range 1-9 MeV and can be used to measure proton spectra at mean energies of ∼1-3 MeV. It has been developed and implemented using a linear accelerator and applied to experiments at the OMEGA laser facility and the National Ignition Facility (NIF). Modeling of the proton slowing in the filters is necessary to construct the spectrum, and the yield and energy uncertainties are ±<10% in yield and ±120 keV, respectively. This spectrometer can be used for in situ calibration of DD-neutron yield diagnostics at the NIF.

6.
Rev Sci Instrum ; 85(11): 11D623, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430199

RESUMEN

Recently developed diagnostic techniques at LLNL require recording backlit images of extremely dense imploded plasmas using hard x-rays, and demand the detector to be sensitive to photons with energies higher than 50 keV [R. Tommasini et al., Phys. Phys. Plasmas 18, 056309 (2011); G. N. Hall et al., "AXIS: An instrument for imaging Compton radiographs using ARC on the NIF," Rev. Sci. Instrum. (these proceedings)]. To increase the sensitivity in the high energy region, we propose to use a combination of two MCPs. The first MCP is operated in a low gain regime and works as a thick photocathode, and the second MCP works as a high gain electron multiplier. We tested the concept of this dual MCP configuration and succeeded in obtaining a detective quantum efficiency of 4.5% for 59 keV x-rays, 3 times larger than with a single plate of the thickness typically used in NIF framing cameras.

7.
Rev Sci Instrum ; 85(11): 11D624, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430200

RESUMEN

Compton radiography is an important diagnostic for Inertial Confinement Fusion (ICF), as it provides a means to measure the density and asymmetries of the DT fuel in an ICF capsule near the time of peak compression. The AXIS instrument (ARC (Advanced Radiography Capability) X-ray Imaging System) is a gated detector in development for the National Ignition Facility (NIF), and will initially be capable of recording two Compton radiographs during a single NIF shot. The principal reason for the development of AXIS is the requirement for significantly improved detection quantum efficiency (DQE) at high x-ray energies. AXIS will be the detector for Compton radiography driven by the ARC laser, which will be used to produce Bremsstrahlung X-ray backlighter sources over the range of 50 keV-200 keV for this purpose. It is expected that AXIS will be capable of recording these high-energy x-rays with a DQE several times greater than other X-ray cameras at NIF, as well as providing a much larger field of view of the imploded capsule. AXIS will therefore provide an image with larger signal-to-noise that will allow the density and distribution of the compressed DT fuel to be measured with significantly greater accuracy as ICF experiments are tuned for ignition.

8.
Rev Sci Instrum ; 85(11): 11D901, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430279

RESUMEN

A magnetic particle time-of-flight (MagPTOF) diagnostic has been designed to measure shock- and compression-bang time using D(3)He-fusion protons and DD-fusion neutrons, respectively, at the National Ignition Facility (NIF). This capability, in combination with shock-burn weighted areal density measurements, will significantly constrain the modeling of the implosion dynamics. This design is an upgrade to the existing particle time-of-flight (pTOF) diagnostic, which records bang times using DD or DT neutrons with an accuracy better than ±70 ps [H. G. Rinderknecht et al., Rev. Sci. Instrum. 83, 10D902 (2012)]. The inclusion of a deflecting magnet will increase D(3)He-proton signal-to-background by a factor of 1000, allowing for the first time simultaneous measurements of shock- and compression-bang times in D(3)He-filled surrogate implosions at the NIF.

9.
Rev Sci Instrum ; 85(4): 043302, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24784597

RESUMEN

CR-39 solid-state nuclear track detectors are widely used in physics and in many inertial confinement fusion (ICF) experiments, and under ideal conditions these detectors have 100% detection efficiency for ∼0.5-8 MeV protons. When the fluence of incident particles becomes too high, overlap of particle tracks leads to under-counting at typical processing conditions (5 h etch in 6N NaOH at 80 °C). Short etch times required to avoid overlap can cause under-counting as well, as tracks are not fully developed. Experiments have determined the minimum etch times for 100% detection of 1.7-4.3-MeV protons and established that for 2.4-MeV protons, relevant for detection of DD protons, the maximum fluence that can be detected using normal processing techniques is ≲3 × 10(6) cm(-2). A CR-39-based proton detector has been developed to mitigate issues related to high particle fluences on ICF facilities. Using a pinhole and scattering foil several mm in front of the CR-39, proton fluences at the CR-39 are reduced by more than a factor of ∼50, increasing the operating yield upper limit by a comparable amount.

10.
Rev Sci Instrum ; 84(4): 043506, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23635195

RESUMEN

The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

11.
Rev Sci Instrum ; 83(10): 10D902, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23126906

RESUMEN

The particle-time-of-flight (pTOF) diagnostic, fielded alongside a wedge range-filter (WRF) proton spectrometer, will provide an absolute timing for the shock-burn weighted ρR measurements that will validate the modeling of implosion dynamics at the National Ignition Facility (NIF). In the first phase of the project, pTOF has recorded accurate bang times in cryogenic DT, DT exploding pusher, and D(3)He implosions using DD or DT neutrons with an accuracy better than ±70 ps. In the second phase of the project, a deflecting magnet will be incorporated into the pTOF design for simultaneous measurements of shock- and compression-bang times in D(3)He-filled surrogate implosions using D(3)He protons and DD-neutrons, respectively.

12.
Rev Sci Instrum ; 83(10): 10D901, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23126905

RESUMEN

The compact Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the National Ignition Facility (NIF) as a National Ignition Campaign diagnostic. The WRF measures the spectrum of protons from D-(3)He reactions in tuning-campaign implosions containing D and (3)He gas; in this work we report on the first proton spectroscopy measurement on the NIF using WRFs. The energy downshift of the 14.7-MeV proton is directly related to the total ρR through the plasma stopping power. Additionally, the shock proton yield is measured, which is a metric of the final merged shock strength.

13.
Rev Sci Instrum ; 81(10): 10D319, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21033845

RESUMEN

The first 3 of 18 neutron time-of-flight (nTOF) channels have been installed at the National Ignition Facility (NIF). The role of these detectors includes yield, temperature, and bang time measurements. This article focuses on nTOF data analysis and quality of results obtained for the first set of experiments to use all 192 NIF beams. Targets produced up to 2×10(10) 2.45 MeV neutrons for initial testing of the nTOF detectors. Differences in neutron scattering at the OMEGA laser facility where the detectors were calibrated and at NIF result in different response functions at the two facilities. Monte Carlo modeling shows this difference. The nTOF performance on these early experiments indicates that the nTOF system with its full complement of detectors should perform well in future measurements of yield, temperature, and bang time.

14.
Rev Sci Instrum ; 81(10): 10D325, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21033848

RESUMEN

The National Ignition Facility (NIF) successfully completed its first inertial confinement fusion (ICF) campaign in 2009. A neutron time-of-flight (nTOF) system was part of the nuclear diagnostics used in this campaign. The nTOF technique has been used for decades on ICF facilities to infer the ion temperature of hot deuterium (D(2)) and deuterium-tritium (DT) plasmas based on the temporal Doppler broadening of the primary neutron peak. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the yield with high accuracy. The NIF nTOF system is designed to measure neutron yield and ion temperature over 11 orders of magnitude (from 10(8) to 10(19)), neutron bang time in DT implosions between 10(12) and 10(16), and to infer areal density for DT yields above 10(12). During the 2009 campaign, the three most sensitive neutron time-of-flight detectors were installed and used to measure the primary neutron yield and ion temperature from 25 high-convergence implosions using D(2) fuel. The OMEGA yield calibration of these detectors was successfully transferred to the NIF.

15.
Med J Armed Forces India ; 63(2): 144-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27407971

RESUMEN

BACKGROUND: There is a paucity of Indian studies on psychiatric morbidity in children. Present work was undertaken in a child guidance clinic in armed forces. METHODS: Retrospective analysis of 213 patients who attended a child guidance clinic was done. RESULTS: Majority (n=138) were boys. 55.9% were referred from paediatric outpatient department while medical officers in periphery referred 38.5%. The diagnoses was mental retardation in 30.97%, behavioral and emotional disorders in 23.06% and neurotic, stress related and somatoform disorders in 15.98% cases.

16.
Physiol Behav ; 68(3): 285-90, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10716537

RESUMEN

Exposure to novel males can disrupt intrauterine implantation of fertilized ova in inseminated female mice, an effect established to involve androgen-dependent male excretions. These experiments were designed to examine potential roles of vesicular and coagulating glands, independently or in conjunction with preputial glands. Inseminated females were randomly assigned to conditions of housing below (1) no males; (2) males with vesicular-coagulating gland removal; (3) males with preputial, vesicular, and coagulating gland removal; or (4) males subjected to sham surgery. Males with accessory glands removed disrupted pregnancy to the same extent as did sham-operated males. Long-term testosterone replacement permitted pregnancy disruption in castrated males with vesicular-coagulating and preputial glands removed. Fertility was not disrupted by preputialectomy, but half of the males without vesicular-coagulating glands could not inseminate females. We suggest that males' capacity to disrupt pregnancy could derive from androgen metabolism that is independent of actions on major accessory glands.


Asunto(s)
Nivel de Alerta/fisiología , Implantación del Embrión/fisiología , Feromonas/fisiología , Vesículas Seminales/fisiología , Atractivos Sexuales/fisiología , Medio Social , Animales , Copulación/fisiología , Femenino , Masculino , Ratones , Embarazo
17.
Appl Opt ; 39(25): 4540-6, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-18350042

RESUMEN

We performed a direct side-by-side comparison of a Shack-Hartmann wave-front sensor and a phase-shifting interferometer for the purpose of characterizing large optics. An expansion telescope of our own design allowed us to measure the surface figure of a 400-mm-square mirror with both instruments simultaneously. The Shack-Hartmann sensor produced data that closely matched the interferometer data over spatial scales appropriate for the lenslet spacing, and much of the <20-nm rms systematic difference between the two measurements was due to diffraction artifacts that were present in the interferometer data but not in the Shack-Hartmann sensor data. The results suggest that Shack-Hartmann sensors could replace phase-shifting interferometers for many applications, with particular advantages for large-optic metrology.

18.
J Child Psychol Psychiatry ; 39(5): 653-62, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9690929

RESUMEN

This study examined the effects of a student-mediated conflict resolution program on primary school (junior kindergarten to grade 5) playground aggression. Mediation teams of grade 5 students (approximately age 10) participated in 15 hours of training according to the model developed by Cunningham, Cunningham, and Martorelli (1997). Following baseline observations, mediation was introduced onto the playgrounds of three schools according to a multiple baseline design. Mediators successfully resolved approximately 90% of the playground conflicts in which they intervened. Direct observations suggest that the student mediation program reduced physically aggressive playground behavior by 51% to 65%. These effects were sustained at 1-year follow-up observations. Teacher and mediator satisfaction questionnaires provided strong support for impact, feasibility, and acceptability of this program.


Asunto(s)
Agresión/psicología , Conflicto Psicológico , Negociación , Grupo Paritario , Juego e Implementos de Juego , Medio Social , Estudiantes/psicología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Resultado del Tratamiento
19.
J Reprod Fertil ; 106(2): 269-74, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8699410

RESUMEN

Inseminated female CF-1 mice (Mus musculus) were exposed on days 1 to 5 of pregnancy to unfamiliar outbred males. In the first experiment, inseminated females were each housed directly with the sire, a preputialectomized male, or an intact male. Both types of novel male attempted to mate with the female during this period, unlike the sire. Reinsemination occurred in a significant proportion of the females that were exposed to novel males; this effect was equivalent for preputialectomized and intact males. In two subsequent experiments, we refined a paradigm of indirect exposure to novel males through a wire-mesh grid, which prevents mating and reinsemination. Two or three males housed directly above each female through a grid disrupt pregnancy in most cases, but housing the males below the females is much less likely to do so. In a final experiment, each inseminated female was housed below two males that were either preputialectomized or sham-preputialectomized. Whereas 29 of 33 undisturbed controls were parturient, only eight of 32 females exposed to sham-preputialectomized males and six of 32 exposed to preputialectomized males were parturient. These results suggest that nonvolatile pheromones are involved in novel-male-induced pregnancy disruptions, but that preputial gland emissions are not necessary for such disruptions.


Asunto(s)
Mantenimiento del Embarazo/fisiología , Glándulas Sebáceas/fisiología , Atractivos Sexuales/fisiología , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos , Pene , Embarazo , Glándulas Sebáceas/cirugía
20.
Prenat Diagn ; 15(4): 363-7, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7617578

RESUMEN

Mitochondrial acetoacetyl-coenzyme A (CoA) thiolase deficiency is an organic aciduria which affects isoleucine and ketone body catabolism. GK16 (the index patient) was affected with this disorder and previous studies had revealed that GK16 was a compound heterozygote with IVS8(+1) gt to tt and A301P mutations. In a subsequent pregnancy, prenatal diagnosis was performed and the fetus's amniocytes were analysed by the polymerase chain reaction (PCR) followed by the heteroduplex detection method on a Mutation Detection Enhancement gel. The fetus was identified as a carrier of the IVS8(+1) mutation. We confirmed the diagnosis by immunoblot analysis of extracted amniocytes and gene analysis with blood filter paper after delivery. This is the first report of prenatal diagnosis of this disorder at the gene level.


Asunto(s)
Acetil-CoA C-Acetiltransferasa/deficiencia , Mitocondrias/enzimología , Ácidos Nucleicos Heterodúplex/análisis , Reacción en Cadena de la Polimerasa/métodos , Diagnóstico Prenatal , Acetil-CoA C-Acetiltransferasa/genética , Dermatoglifia del ADN , Análisis Mutacional de ADN , Exones , Femenino , Humanos , Mutación , Polimorfismo de Longitud del Fragmento de Restricción , Embarazo
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