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1.
Climacteric ; 27(3): 326-328, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38288691

RESUMEN

The use of compounded bioidentical hormone therapy (cBHT) continues to grow in popularity despite the availability of many US Food and Drug Administration-approved hormone products produced in different formulations and dosages. Numerous claims made by proponents of cBHT are not substantiated by properly designed studies. Valid concerns about purity, efficacy, bioavailability and safety of cBHT have been raised. Since patient welfare is the first duty of health professionals, promoting and prescribing cBHT as first-line therapy violates a number of ethical tenets of medical and pharmacy practice and should be discouraged without a compelling reason.


Asunto(s)
Composición de Medicamentos , Terapia de Reemplazo de Estrógeno , Humanos , Femenino , Menopausia , Estados Unidos , United States Food and Drug Administration
2.
Phys Rev Lett ; 128(18): 185002, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35594117

RESUMEN

Evolution of the hot spot plasma conditions was measured using high-resolution x-ray spectroscopy at the National Ignition Facility. The capsules were filled with DD gas with trace levels of Kr and had either a high-density-carbon (HDC) ablator or a tungsten (W)-doped HDC ablator. Time-resolved measurement of the Kr Heß spectra, absolutely calibrated by a simultaneous time-integrated measurement, allows inference of the electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. By matching the calculated hot spot emission using a collisional-radiative code to experimental observations, the hot spot size and areal density are determined. These advanced spectroscopy techniques further reveal the effect of W dopant in the ablator on the hot spot parameters for their improved implosion performance.

3.
Rev Sci Instrum ; 92(4): 043531, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243385

RESUMEN

This paper describes a new class of focusing crystal forms for the x-ray Bragg crystal spectroscopy of small, point-like, x-ray sources. These new crystal forms are designed with the aid of sinusoidal spirals, a family of curves, whose shapes are defined by only one parameter, which can assume any real value. The potential of the sinusoidal spirals for the design x-ray crystal spectrometers is demonstrated with the design of a toroidally bent crystal of varying major and minor radii for measurements of the extended x-ray absorption fine structure near the Ta-L3 absorption edge at the National Ignition Facility.

4.
Rev Sci Instrum ; 89(10): 10F118, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30399766

RESUMEN

The here-described spectrometer was developed for the extended x-ray absorption fine structure spectroscopy of high-density plasmas at the National Ignition Facility. It employs as the Bragg reflecting element a new type of toroidally bent crystal with a constant and very large major radius R and a much smaller, locally varying, minor radius r. The focusing properties of this crystal and the experimental arrangement of the source and detector make it possible to (a) fulfill the conditions for a perfect imaging of an ideal point source for each wavelength, (b) obtain a high photon throughput, (c) obtain a high spectral resolution by eliminating the effects of source-size broadening, and (d) obtain a one-dimensional spatial resolution with a high magnification perpendicular to the main dispersion plane.

5.
Rev Sci Instrum ; 89(10): 10F125, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30399848

RESUMEN

A high resolution, Diagnostic Instrument Manipulator (DIM)-based x-ray Bragg crystal spectrometer has been calibrated for and deployed at the National Ignition Facility (NIF) to diagnose plasma conditions in ignition capsules near stagnation times. The spectrometer has two conical crystals in the Hall geometry focusing rays from the Kr Heα, Lyα, and Heß complexes onto a streak camera, with the physics objectives of measuring time-resolved electron density and temperature through observing Stark broadening and the relative intensities of dielectronic satellites. A third von Hámos crystal that time-integrates the Kr Heα, Heß and intervening energy range provides in situ calibration for the streak camera signals. The spectrometer has been absolutely calibrated using a microfocus x-ray source, an array of CCD and single-photon-counting detectors, and multiple K- and L-absorption edge filters at the Princeton Plasma Physics Laboratory (PPPL) x-ray laboratory. Measurements of the integrated reflectivity, energy range, and energy resolution for each crystal are discussed. These calibration data provide absolute x-ray signal levels for NIF measurements, enabling precise filter selection and comparisons to simulations.

6.
Phys Rev Lett ; 121(9): 095002, 2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-30230893

RESUMEN

We report on the first multilocation electron temperature (T_{e}) and flow measurements in an ignition hohlraum at the National Ignition Facility using the novel technique of mid-Z spectroscopic tracer "dots." The measurements define a low resolution "map" of hohlraum plasma conditions and provide a basis for the first multilocation tests of particle and energy transport physics in a laser-driven x-ray cavity. The data set is consistent with classical heat flow near the capsule but reduced heat flow near the laser entrance hole. We evaluate the role of kinetic effects, self-generated magnetic fields, and instabilities in causing spatially dependent heat transport in the hohlraum.

7.
Rev Sci Instrum ; 87(11): 11E344, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910374

RESUMEN

A high resolution (E/ΔE = 1200-1800) Bragg crystal x-ray spectrometer is being developed to measure plasma parameters in National Ignition Facility experiments. The instrument will be a diagnostic instrument manipulator positioned cassette designed mainly to infer electron density in compressed capsules from Stark broadening of the helium-ß (1s2-1s3p) lines of krypton and electron temperature from the relative intensities of dielectronic satellites. Two conically shaped crystals will diffract and focus (1) the Kr Heß complex and (2) the Heα (1s2-1s2p) and Lyα (1s-2p) complexes onto a streak camera photocathode for time resolved measurement, and a third cylindrical or conical crystal will focus the full Heα to Heß spectral range onto an image plate to provide a time integrated calibration spectrum. Calculations of source x-ray intensity, spectrometer throughput, and spectral resolution are presented. Details of the conical-crystal focusing properties as well as the status of the instrumental design are also presented.

8.
J Anim Sci ; 91(9): 4553-62, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23825347

RESUMEN

A century ago students were exposed to livestock judging and meat judging, though each was taught as an independent entity. Fifty years ago universities started combining subjects involving the evaluation process, whether characteristics involved traits of the live animal or those related to meat value. Universities developed a meat animal evaluation contest (MAEC) that included breeding livestock, market livestock, and meat products. Using production records, students culled, ranked, priced, and answered questions about breeding and market cattle, swine, and sheep. For market livestock, ranks and values were scored on carcass data after the livestock were harvested. Students graded, ranked, answered questions, and priced meat products. A communications component involved students being given a problem to be discussed as a group presentation. In 1964, the first MAEC was conducted at Rath Packing Co., Waterloo, IA, and included 40 students. In 1967, the contest was held at The Farmbest Co. and IBP of Denison, IA, and included 87 students. In 1968, the MAEC moved to the Knights of Ak-Sar-Ben, Omaha, NE, and by 1988, 187 students (22 universities) competed. In 1995, the MAEC moved to the United Stockyards Co., St. Joseph, MO. Starting in 2004, it moved to various universities (South Dakota State University, Oklahoma State University, University of Nebraska, and Texas Tech University). The MAEC has stimulated students to better learn and understand the details of meat animal evaluation and has encouraged the development of evaluation courses as well as satellite and symposia programs. To date, over 6,000 students representing 40 universities have participated.


Asunto(s)
Crianza de Animales Domésticos/historia , Composición Corporal , Bovinos/fisiología , Carne/análisis , Oveja Doméstica/fisiología , Sus scrofa/fisiología , Crianza de Animales Domésticos/educación , Animales , Historia del Siglo XX , Historia del Siglo XXI , Estados Unidos
9.
Phys Rev Lett ; 106(8): 085003, 2011 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-21405579

RESUMEN

The first soft x-ray radiation flux measurements from hohlraums using both a 96 and a 192 beam configuration at the National Ignition Facility have shown high x-ray conversion efficiencies of ∼85%-90%. These experiments employed gold vacuum hohlraums, 6.4 mm long and 3.55 mm in diameter, heated with laser energies between 150-635 kJ. The hohlraums reached radiation temperatures of up to 340 eV. These hohlraums for the first time reached coronal plasma conditions sufficient for two-electron processes and coronal heat conduction to be important for determining the radiation drive.

10.
J Anim Sci ; 89(7): 2280-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21357452

RESUMEN

The Animal Sciences Academic Quadrathlon (AQ) provides opportunities for teams of undergraduate animal and dairy science students to participate in regional American Society of Animal Science (ASAS)/American Dairy Science Association (ADSA) meetings and to collectively exhibit their knowledge and talents competitively in 4 categories: 1) solving practical, hands-on, laboratory-type problems; 2) providing written answers to essay-type questions about principles and concepts; 3) preparing and communicating orally and extemporaneously topics of current animal science interest; and 4) quickly responding to short-answer questions provided in the form of double-elimination quiz bowls. Each team is selected by winning the local AQ at their university. Overall and individual category winning teams are recognized, but team rankings are not emphasized. The ASAS/ADSA members provide leadership for organizing and conducting the AQ, and ASAS and each university provide travel expenses for students. The ultimate purpose is to stimulate academic excellence among undergraduate students and for the students to attend ASAS/ADSA regional scientific meetings to meet faculty and students and to attend scientific research presentations. The purpose of this document was to provide a history of the event and to make recommendations for its improvement. The AQ was conceived in 1967. During the next 10 yr, an ASAS committee developed procedures for a trial AQ held in 1980 at the ASAS Midwestern Section, Kansas State University-Manhattan, and in the next year the first official AQ was held at the ASAS Midwestern Section at the University of Nebraska-Lincoln. Starting in 1985, AQ programs were initiated at the other 3 ASAS sectional meetings, and an estimated 50,000 students representing 60 universities have participated in AQ programs since that time. If the AQ is to continue its improvement over time, it will greatly depend on sustained ASAS/ADSA faculty interest and support, as well as greater adherence to the original AQ procedures.


Asunto(s)
Crianza de Animales Domésticos/educación , Sociedades Científicas/organización & administración , Crianza de Animales Domésticos/normas , Animales , Educación en Veterinaria/normas , Estados Unidos , Medicina Veterinaria/normas
11.
Rev Sci Instrum ; 81(10): 10D938, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21033965

RESUMEN

On the National Ignition Facility (NIF), hot electrons generated in laser heated Hohlraums are inferred from the >20 keV bremsstrahlung emission measured with the time integrated FFLEX broadband spectrometer. New high energy (>200 keV) time resolved channels were added to infer the generated >170 keV hot electrons that can cause ignition capsule preheat. First hot electron measurements in near ignition scaled Hohlraums heated by 96-192 NIF laser beams are presented.

12.
Rev Sci Instrum ; 81(10): 10E321, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21034019

RESUMEN

The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×10(15) W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14) W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.

13.
Tob Control ; 17(5): 357-60, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18603604

RESUMEN

OBJECTIVE: To examine current tobacco policy in US prisons and explore changes in prison tobacco policies over time. DATA SOURCE: Telephone survey of the 52 US departments of correction. MAIN OUTCOME MEASURES: Current tobacco policy; distribution of free tobacco; availability of smoking cessation programming and cessation aids. PARTICIPANTS: Complete responses were received from 51 of 52 (98%) departments, while one provided partial information. RESULTS: The majority of correctional systems (60%) reported total tobacco bans on prison grounds, with most remaining facilities (27%) having an indoor ban on tobacco use. No prisons distributed free tobacco. No major violence was reported relating to the implementation of stricter tobacco policies; however many respondents noted that tobacco became a major contraband item following the implementation of a total ban. While most prison systems with an indoor tobacco ban (86%) reported having tobacco cessation programmes, few of those with total bans (39%) continued such programmes after the initial transition period. CONCLUSION: Total tobacco bans have often been accompanied by the termination of tobacco cessation programmes. Such actions undermine efforts to promote long-term cessation resulting in a missed public health opportunity.


Asunto(s)
Prisiones/estadística & datos numéricos , Prevención del Hábito de Fumar , Política de Salud/tendencias , Promoción de la Salud/métodos , Encuestas Epidemiológicas , Humanos , Cese del Hábito de Fumar/métodos , Estados Unidos
15.
Phys Rev Lett ; 95(21): 215004, 2005 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-16384150

RESUMEN

The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.

16.
Phys Rev Lett ; 94(5): 055006, 2005 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-15783658

RESUMEN

A series of experiments conducted on the HELEN laser system [M. J. Norman, Appl. Opt.4120023497], into thermal x-ray generation from hohlraum targets using 527 nm (2omega) wavelength laser light, has shown that it is possible to exceed radiation temperatures previously thought limited by high levels of superthermal or hot electron production or stimulated backscatter. This Letter questions whether the assumptions traditionally applied to hohlraum design with respect to hot plasma filling and the use of 2omega light are too conservative.

17.
Phys Rev Lett ; 93(6): 065002, 2004 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-15323638

RESUMEN

We present measurements of the absolute albedos of hohlraums made from gold or from high-Z mixtures. The measurements are performed over the range of radiation temperatures (70-100 eV) expected during the foot of an indirect-drive temporally shaped ignition laser pulse, where accurate knowledge of the wall albedo (i.e., soft x-ray wall reemission) is most critical for determining capsule radiation symmetry. We find that the gold albedo agrees well with calculations using the supertransition array opacity model, potentially providing additional margin for inertial confinement fusion ignition.

18.
Fetal Diagn Ther ; 19(5): 456-61, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15305104

RESUMEN

OBJECTIVE: To compare pregnancy-associated plasma protein-A (PAPP-A) serum levels at 10(+1) to 14(+6) weeks gestation in groups of patients with different obstetrical outcomes. PATIENTS AND METHODS: The medical records of women who had consented to donate blood for biochemical research purposes while their pregnancies were uncomplicated were reviewed to define the clinical groups. After the clinical groups were defined, the donated maternal serum samples were thawed and PAPP-A measured by ELISA. ANOVA was used to compare mean values within groups. RESULT: All groups had similar gestational ages at blood donation (overall mean 12.5 weeks; no difference in gestational age was found within groups, p = 0.18). The overall PAPP-A serum level was 2.01 mIU/ml with only the spontaneous abortion group having a statistical different PAPP-A level (0.09 mIU/ml; p < 0.001). CONCLUSION: These data suggest that those women who experienced spontaneous abortions had significantly different mean PAPP-A serum levels at 10(+1) to 14(+6) weeks gestation. Several lines of evidence suggest that downregulation of insulin-like growth factor-II availability due to a decreased PAPP-A serum level may be the cause of spontaneous abortion in these women.


Asunto(s)
Aborto Espontáneo/sangre , Aborto Espontáneo/etiología , Proteína Plasmática A Asociada al Embarazo/metabolismo , Femenino , Edad Gestacional , Humanos , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Modelos Biológicos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos
19.
J Matern Fetal Neonatal Med ; 12(5): 349-52, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12607769

RESUMEN

A first-trimester primigravid patient presented with hyperemesis and malaise. Work-up was consistent with primary hyperparathryoidism. During acute treatment, she developed generalized motor seizures considered to be secondary to hypercalcemia. Evaluation and treatment of women with primary hyperparathyroidism and hypercalcemia are reviewed, and the pathogenesis of seizures associated with hypercalcemia is discussed.


Asunto(s)
Adenoma/diagnóstico , Hipercalcemia/etiología , Hiperparatiroidismo/etiología , Neoplasias de las Paratiroides/diagnóstico , Complicaciones del Embarazo , Convulsiones/etiología , Adenoma/complicaciones , Adenoma/cirugía , Adulto , Anticonvulsivantes/uso terapéutico , Femenino , Fluidoterapia/métodos , Número de Embarazos , Humanos , Hipercalcemia/terapia , Hiperemesis Gravídica/etiología , Hiperparatiroidismo/cirugía , Hormona Paratiroidea/sangre , Neoplasias de las Paratiroides/complicaciones , Neoplasias de las Paratiroides/cirugía , Paratiroidectomía , Embarazo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/terapia , Primer Trimestre del Embarazo , Convulsiones/tratamiento farmacológico , Resultado del Tratamiento
20.
Arch Pediatr Adolesc Med ; 155(8): 934-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11483122

RESUMEN

BACKGROUND: While cytochrome P4501A2 is the primary pathway for theophylline (aminophylline ethylenediamine) metabolism in adults, it is developmentally immature in the newborn. OBJECTIVE: To report the developmental differences in theophylline toxicokinetics of neonates. DESIGN: Case series. Three premature neonates received inadvertent intravenous overdoses of theophylline for apnea of prematurity while in newborn intensive care. Maximum serum concentrations ranged from 55 to 123 mg/L. Theophylline-derived caffeine levels plateaued at 8.4 to 13 mg/L and did not decline during the sampling period. All newborns experienced sinus tachycardia and agitation. Sequential theophylline and caffeine serum levels were obtained periodically for 62 to 100 hours. In contrast to older children and adults, in whom theophylline disposition follows zero-order kinetics at high concentrations, a monoexponential function best described theophylline elimination in the premature newborn, with half-lives ranging from 24.7 to 36.5 hours and estimated clearance from 0.02 to 0.05 L/kg per hour. These values are consistent with those previously reported in neonates. All patients were treated with supportive care without invasive procedures. No seizures or apparent sequelae occurred. CONCLUSION: Developmental differences in the balance between nonrenal (ie, metabolic) and renal elimination pathways produce the unique toxicokinetics of theophylline in the neonate.


Asunto(s)
Apnea/tratamiento farmacológico , Broncodilatadores/efectos adversos , Enfermedades del Prematuro/tratamiento farmacológico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Taquicardia Sinusal/inducido químicamente , Teofilina/efectos adversos , Apnea/diagnóstico , Broncodilatadores/administración & dosificación , Broncodilatadores/farmacocinética , Relación Dosis-Respuesta a Droga , Estudios de Seguimiento , Humanos , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Infusiones Intravenosas , Unidades de Cuidado Intensivo Neonatal , Masculino , Síndrome de Dificultad Respiratoria del Recién Nacido/diagnóstico , Medición de Riesgo , Taquicardia Sinusal/diagnóstico , Teofilina/administración & dosificación , Teofilina/farmacocinética
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