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1.
Rev Sci Instrum ; 91(4): 043508, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357683

RESUMEN

A line VISAR (Velocity Interferometer System for Any Reflector) has been designed and commissioned at the Sandia National Laboratory's Z-machine. The instrument consists of an F/2 collection system, beam transport, and an interferometer table that contains two Mach-Zehnder type interferometers and an eight channel Gated Optical Imaging (GOI) system. The VISAR probe laser operates at the 532 nm wavelength, and the GOI bandpass is 540-600 nm. The output of each interferometer is passed to an optical streak camera with four selectable sweep speeds. The system is designed with three interchangeable optics modules to select a full field of view of 1 mm, 2 mm, or 4 mm. The optical beam transport system connects the target image plane to the interferometers and the gated optical imagers. The target is integrated into a sacrificial final optics assembly that is integral to the transport beamline.

2.
Int J Obes (Lond) ; 41(6): 831-834, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28077861

RESUMEN

This paper elucidates the challenges surrounding the economics of some popular obesity-related policy proposals. Solid economic justifications for anti-obesity policies are often lacking, and evidence suggests policies like fat and soda taxes or restrictions on food stamp spending are unlikely to substantively affect obesity prevalence. In short, many of the same factors that make obesity such a complicated and multifaceted issue extend to the economic analysis of public health policies.


Asunto(s)
Promoción de la Salud/economía , Política Nutricional , Obesidad/prevención & control , Formulación de Políticas , Impuestos/economía , Bebidas Gaseosas/economía , Comercio/economía , Comercio/legislación & jurisprudencia , Comida Rápida/economía , Conducta Alimentaria , Asistencia Alimentaria/economía , Asistencia Alimentaria/legislación & jurisprudencia , Programas de Gobierno , Humanos , Obesidad/economía , Obesidad/epidemiología , Salud Pública , Estados Unidos
4.
Mol Psychiatry ; 21(3): 357-63, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26324104

RESUMEN

Methylation of the SKA2 (spindle and kinetochore-associated complex subunit 2) gene has recently been identified as a promising biomarker of suicide risk. Based on this finding, we examined associations between SKA2 methylation, cortical thickness and psychiatric phenotypes linked to suicide in trauma-exposed veterans. About 200 trauma-exposed white non-Hispanic veterans of the recent conflicts in Iraq and Afghanistan (91% male) underwent clinical assessment and had blood drawn for genotyping and methylation analysis. Of all, 145 participants also had neuroimaging data available. Based on previous research, we examined DNA methylation at the cytosine-guanine locus cg13989295 as well as DNA methylation adjusted for genotype at the methylation-associated single nucleotide polymorphism (rs7208505) in relationship to whole-brain cortical thickness, posttraumatic stress disorder symptoms (PTSD) and depression symptoms. Whole-brain vertex-wise analyses identified three clusters in prefrontal cortex that were associated with genotype-adjusted SKA2 DNA methylation (methylation(adj)). Specifically, DNA methylation(adj) was associated with bilateral reductions of cortical thickness in frontal pole and superior frontal gyrus, and similar effects were found in the right orbitofrontal cortex and right inferior frontal gyrus. PTSD symptom severity was positively correlated with SKA2 DNA methylation(adj) and negatively correlated with cortical thickness in these regions. Mediation analyses showed a significant indirect effect of PTSD on cortical thickness via SKA2 methylation status. Results suggest that DNA methylation(adj) of SKA2 in blood indexes stress-related psychiatric phenotypes and neurobiology, pointing to its potential value as a biomarker of stress exposure and susceptibility.


Asunto(s)
Proteínas Cromosómicas no Histona/genética , Metilación de ADN/genética , Polimorfismo de Nucleótido Simple/genética , Corteza Prefrontal/patología , Trastornos por Estrés Postraumático/genética , Trastornos por Estrés Postraumático/prevención & control , Adulto , Depresión/etiología , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Guerra de Irak 2003-2011 , Modelos Lineales , Masculino , Neuroimagen , Escalas de Valoración Psiquiátrica , Trastornos por Estrés Postraumático/complicaciones , Veteranos , Adulto Joven
5.
Transbound Emerg Dis ; 63(2): 203-14, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25052324

RESUMEN

This study evaluates the economic consequences of a Rift Valley Fever outbreak, a virus that spreads from livestock to humans, often through mosquitoes. Developing a 'one health' economic framework, economic impacts on agricultural producers and consumers, government costs of response, costs and disruptions to non-agricultural activities in the epidemiologically impacted region, and human health costs (morbidity and mortality) are estimated. We find the agricultural firms bear most of the negative economic impacts, followed by regional non-agricultural firms, human health and government. Further, consumers of agricultural products benefit from small outbreaks due to bans on agricultural exports.


Asunto(s)
Brotes de Enfermedades/veterinaria , Fiebre del Valle del Rift/epidemiología , Vigilancia de Guardia/veterinaria , Zoonosis/epidemiología , Animales , Culicidae/virología , Brotes de Enfermedades/economía , Brotes de Enfermedades/prevención & control , Humanos , Insectos Vectores/virología , Ganado/virología , Estados Unidos/epidemiología , Zoonosis/economía , Zoonosis/prevención & control
6.
J Anim Sci ; 93(5): 2045-55, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26020300

RESUMEN

Although genetic tests for many economically important beef cattle traits are commercially available, additional information is needed to help the industry better understand how the results from these tests translate into phenotypic outcomes. This information has important implications for marker-assisted management. The objective of this research was to determine the relationship between molecular breeding values (MBV) characterizing yield grade and marbling and distributions of phenotypic outcomes for yield grade and quality grade. Using data collected from commercially-fed cattle, mixed-model regression equations were estimated for yield grade and quality grade outcomes for both the full sample of commercial cattle (n= 8,995) and a subsample of black-hided steers (n = 4,790). Significant yield grade (P < 0.01) and marbling (P < 0.01) MBV effects were found. However, the yield grade MBV held up better at predicting phenotypic outcomes than the marbling MBV. Estimated conditional probability mass functions of yield and quality grade outcomes for the general population and black-hided steers were similar. Since distributions for black-hided steers were expected to be more applicable from a management perspective, we focused our analysis on these animals. For example, black-hided steers with "low" genetic potential for yield grade and marbling had about a 29% chance of achieving the base price or better on a price grid (yield grade 3 or lower and quality grade Low Choice or better). Increasing genetic potential for marbling increased the likelihood of achieving this same outcome. However, increasing genetic potential for yield grade was unlikely to increase overall carcass quality given its large deleterious effect on quality grade outcomes. Instead, simultaneous improvements in genetic potential for yield grade and marbling offered much more reliable improvements in overall carcass quality. For example, an animal with "moderate" genetic potential for both yield grade and marbling had a 46% chance of achieving the base price or better on a price grid, and an animal with the maximum observed MBV for these traits had a 66% chance of achieving this same outcome. Although the yield grade MBV held up better at predicting phenotypic outcomes, shifts in the distributions of yield grade and quality grade suggested that these increases were largely determined by the marbling MBV.


Asunto(s)
Cruzamiento/métodos , Bovinos/crecimiento & desarrollo , Bovinos/genética , Carne/normas , Fenotipo , Animales , Análisis de Regresión , Especificidad de la Especie
7.
J Anim Sci ; 92(7): 3142-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24802037

RESUMEN

This study was designed to explore consumers' perceptions about and knowledge of USDA beef quality grades. Data were collected from over 1,000 consumers in online surveys in November and December 2013, and estimates were weighted to force the sample to mirror the U.S. population in terms of age, gender, education, and region of residence. When asked to rank Prime, Choice, and Select grades in terms of leanness, only 14.4% provided the correct ranking with 57.1% of respondents incorrectly indicating steaks grading Prime were the leanest. Despite perceptions that the Prime name indicated the leanest product, in a subsequent question, 55.6% of respondents thought Prime grade to be the juiciest of the 3 grades. In addition to inquiring about perceptions of the grade names, respondents also indicated perceptions of pictures of steaks. Only 14.5% of respondents correctly matched the steak pictures with their corresponding USDA quality grade name, an outcome that is statistically worse than would have occurred through pure random matching (P = 0.03). When asked to match pictures of steaks with expected prices, 54.8% of respondents incorrectly matched the picture of the Prime steak with the lowest price level. More highly educated consumers with greater preferences for steak consumption were more likely to provide correct answers. Results reveal substantial confusion over quality grading nomenclature and suggest the need for more education or for a transition toward more descriptive terminology at the retail level.


Asunto(s)
Comportamiento del Consumidor , Calidad de los Alimentos , Carne/normas , United States Department of Agriculture/normas , Adolescente , Adulto , Factores de Edad , Anciano , Animales , Bovinos , Comportamiento del Consumidor/estadística & datos numéricos , Escolaridad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estados Unidos , Adulto Joven
8.
J Anim Sci ; 89(5): 1260-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21278104

RESUMEN

Although several previous studies have identified associations between cattle carcass characteristics and various SNP, comparatively little work has sought to validate the marker panels currently sold and marketed by commercial genotyping companies. Panels typically use a handful of SNP, but these range from as few as 2 to more than 100. Data from 764 commercially fed steers and heifers were used to assess the relationships of growth and carcass traits and Igenity panel scores for ADG, marbling (or percentage of USDA Choice), rib-eye area (REA), tenderness, fat thickness, and USDA Yield grade (YG). Results revealed statistically significant, but low, correlations between carcass measurements and corresponding Igenity panel scores. Genetic correlations were computed among the various Igenity panels and demonstrated either that several common markers existed across the panels or that markers across panels were in high linkage disequilibrium. Across all breeds, the genotypic correlations between the Igenity panel scores for ADG, REA, marbling, and YG with observed ADG, REA, USDA Quality grade, and YG at slaughter were 0.51, 0.38, 0.63, and 0.59 (P < 0.01), respectively. The partial effects of the Igenity marbling panel persisted in a multivariate regression model. Net return was significantly affected only by marbling panel score; a 1-unit increase in marbling panel score increased the net return by an estimated $7.53 per animal.


Asunto(s)
Composición Corporal/fisiología , Bovinos/fisiología , Carne/normas , Animales , Composición Corporal/genética , Bovinos/genética , Femenino , Marcadores Genéticos , Masculino , Análisis Multivariante , Polimorfismo de Nucleótido Simple , Análisis de Regresión
9.
J Anim Sci ; 85(8): 1865-72, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17431048

RESUMEN

Previous research has identified differences in carcass characteristics across SNP in the bovine leptin gene at slaughter, but before feedlot operators implement selection and sorting strategies, more information is needed to determine how carcass characteristics change over time. The objective of this study was to investigate the effect of 2 leptin SNP on growth curve parameters for BW and backfat. Two SNP (UASMS2 and R25C) were genotyped on 1,653 cross-bred steers and heifers in a commercial feedlot. Up to 4 serial measures of BW and ultrasound estimates of backfat thickness were taken for each animal from the time of placement on feed to slaughter. The measures were used to estimate growth models that describe changes in BW and backfat thickness as a function of days on feed. Data analysis was carried out by estimating nonlinear mixed models to determine the individual and joint effect of each SNP on growth curve parameters. Brody growth curves were fit to the BW data. Variations in the R25C SNP did not significantly affect growth parameters individually or in combination with the UASMS2 SNP. Variations in the UASMS2 SNP were significant in Brody growth curve parameters for BW growth (P < 0.001). The genotype UASMS2-CC was the heaviest at the beginning of the feeding period and exhibited the largest asymptotic mature BW, but UASMS2-TT cattle exhibited the fastest rate of BW growth. A modified power function was fit to the serial ultrasound backfat measures. Models that included the combined effect of the R25C and UASMS2 SNP provided the best fit to the data. Genotypes differed significantly in power function parameters for backfat growth (P < 0.001). The R25C-CC/UASMS2-TT cattle had the smallest backfat thickness at placement. The genotype R25C-CC/UASMS2-TT exhibited the fastest backfat growth rate, whereas backfat in R25C-CC/UASMS2-CC cattle grew at the slowest rate. The association between leptin genotype and growth in BW and backfat presents opportunities to identify genetically distinct cattle and to differentially optimize feeding times accordingly.


Asunto(s)
Tejido Adiposo/crecimiento & desarrollo , Peso Corporal/genética , Bovinos/crecimiento & desarrollo , Bovinos/genética , Leptina/genética , Polimorfismo de Nucleótido Simple/genética , Animales , Femenino , Genotipo , Leptina/fisiología , Funciones de Verosimilitud , Masculino , Modelos Biológicos
10.
Leuk Lymphoma ; 18(3-4): 329-34, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8535201

RESUMEN

Granulocyte transfusions may be beneficial in neutropenic patients with progressive infections despite appropriate antibiotics. In order to evaluate both the feasibility of granulocyte collection in normal donors receiving granulocyte colony-stimulating factor (G-CSF) and the efficacy of infusing these cells into neutropenic patients with progressive sepsis, four donors received between 5-10 micrograms/kg G-CSF per day and underwent leucapheresis within a day of the first dose. Different red cell sedimenting agents and interface settings were evaluated to determine the optimal method of granulocyte collection. The number of granulocytes collected, the peripheral blood granulocyte level in the recipient at various time points after infusion, and the clinical response were evaluated. Results showed that G-CSF and the leucaphereses caused mild to moderate fatigue in two donors and profound fatigue and a brief episode of hypoxia in one donor. Efficient granulocyte collections were only obtained using dextran 40 or dextran 70 as the sedimenting agent and a deep interface setting which extended sampling into the upper red cell layer. Infusion of granulocytes obtained with this technique resulted in a sustained increase in circulating granulocyte numbers in three recipients, one of whom gained significant clinical benefit. In conclusion, granulocyte transfusions from donors given G-CSF are feasible and may be clinically beneficial, particularly if given early in the course of infection in neutropenic patients.


Asunto(s)
Donantes de Sangre , Factor Estimulante de Colonias de Granulocitos/farmacología , Transfusión de Leucocitos , Neutropenia/terapia , Infecciones Oportunistas/complicaciones , Sepsis/complicaciones , Adulto , Progresión de la Enfermedad , Resultado Fatal , Femenino , Granulocitos/efectos de los fármacos , Humanos , Masculino , Neutropenia/complicaciones , Estimulación Química
12.
Chest ; 100(5): 1293-9, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1935284

RESUMEN

The purpose of this article is to describe the spectrum and frequency of diseases presenting as unexplained dyspnea and to develop a logical diagnostic approach to such patients. Seventy-two consecutive physician-referred patients had dyspnea greater than one-month duration unexplained by the initial history, physical examination, chest roentgenogram, and spirometry. Patients underwent a standard diagnostic evaluation. A definite cause for dyspnea was recognized in 58 patients, and no answer was found in 14. Twenty-two diseases were recognized in the patient group. Dyspnea was due to pulmonary disease in 26 (36 percent) patients, cardiac disease in ten (14 percent) patients, hyperventilation in 14 (19 percent) patients, and only 3 patients had extrathoracic disease causing dyspnea. Age younger than 40 years, intermittent dyspnea, and normal alveolar-arterial oxygen pressure difference (P[A-a]O2) at rest breathing room air was strongly predictive of bronchial hyperreactivity or hyperventilation. No patient diagnosed as having disease of the lung parenchyma or vasculature had a P(A-a)O2 less than or equal to 20 mm Hg. The differential diagnosis to explain dyspnea in patients with nondirective histories, normal findings from physical examinations, normal chest roentgenograms, and normal spirograms is extensive. The patient's age and measurement of gas exchange at rest help to formulate a diagnostic approach.


Asunto(s)
Disnea/etiología , Adulto , Anciano , Obstrucción de las Vías Aéreas/complicaciones , Estudios de Seguimiento , Reflujo Gastroesofágico/complicaciones , Cardiopatías/complicaciones , Humanos , Hiperventilación/complicaciones , Enfermedades Renales/complicaciones , Enfermedades Pulmonares/complicaciones , Anamnesis , Examen Físico , Radiografía Torácica , Hipersensibilidad Respiratoria/complicaciones , Espirometría , Enfermedades de la Tiroides/complicaciones
13.
Lancet ; 2(8668): 891-5, 1989 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-2477656

RESUMEN

Granulocyte colony-stimulating factor (G-CSF) was administered by continuous subcutaneous infusion to 15 patients with non-myeloid malignancies treated by high-dose chemotherapy and autologous bone marrow infusion. G-CSF was given at variable dosage based on neutrophil count. Sustained serum levels of G-CSF were achieved. Neutrophil recovery was accelerated in G-CSF treated patients compared with 18 historical controls and exceeded 0.5 x 10(9)/l at a mean of 11 days after marrow infusion compared with 20 days for controls, a significant difference. This reduction led to significantly fewer days of parenteral antibiotic therapy, 11 versus 18 days in controls, and less isolation in reverse-barrier nursing, 10 versus 18 days.


Asunto(s)
Trasplante de Médula Ósea/métodos , Busulfano/administración & dosificación , Factores Estimulantes de Colonias/farmacología , Ciclofosfamida/administración & dosificación , Enfermedad de Hodgkin/terapia , Linfoma no Hodgkin/terapia , Neoplasias de Células Germinales y Embrionarias/terapia , Neutropenia/tratamiento farmacológico , Agranulocitosis , Examen de la Médula Ósea , Busulfano/uso terapéutico , Ensayos Clínicos como Asunto , Factores Estimulantes de Colonias/efectos adversos , Factores Estimulantes de Colonias/sangre , Terapia Combinada , Ciclofosfamida/uso terapéutico , Esquema de Medicación , Evaluación de Medicamentos , Factor Estimulante de Colonias de Granulocitos , Enfermedad de Hodgkin/sangre , Humanos , Bombas de Infusión , Infusiones Parenterales , Recuento de Leucocitos/efectos de los fármacos , Linfoma no Hodgkin/sangre , Neoplasias de Células Germinales y Embrionarias/sangre , Neutropenia/inducido químicamente , Proteínas Recombinantes/farmacocinética , Factores de Tiempo
16.
Bests Rev Life Health Insur Ed ; 82(4): 32, 36, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10252111
17.
Ophthalmic Surg ; 11(10): 722-4, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6969874

RESUMEN

Since it is impossible to sterilize the surgical field in ocular surgery, postoperative endophthalmitis remains a serious complication of intraocular surgery. The surgeon should take all reasonable precautions to avoid this disaster. We believe that this includes isolating the skin and eyelids from the operative field with the incise drape.


Asunto(s)
Ropa de Cama y Ropa Blanca , Oftalmología/instrumentación , Endoftalmitis/prevención & control , Humanos , Esterilización , Infección de la Herida Quirúrgica/prevención & control
18.
Ann Ophthalmol ; 12(9): 1017-8, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6927211

RESUMEN

Cavernous hemangioma of the optic disc and retina is a vascular hamartoma composed of clusters of thin-walled saccular aneurysms partially filled with dark venous blood. It is now considered a neuro-oculo-cutaneous syndrome whose mode of inheritance is probably autosomal dominant. This report describes a cavernous hemangioma of the optic disc in a patient without skin or neurological findings. Its clinical appearance, generally benign ocular nature, and occasional association with central nervous system or cutaneous lesions is emphasized.


Asunto(s)
Neoplasias del Ojo/diagnóstico , Hemangioma Cavernoso/diagnóstico , Disco Óptico , Adulto , Neoplasias del Ojo/genética , Angiografía con Fluoresceína , Hemangioma Cavernoso/genética , Humanos , Masculino , Síndrome
20.
Biophys Chem ; 11(1): 9-16, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7357065

RESUMEN

The kinetics of an elementary reaction step are discussed from the viewpoint of the stochastic theory of chemical kinetics. The general form of the rate constant found in the stochastic approach is described and compared with the expression from transition state theory. Whereas the stochastic theory predicts a rate enhancement in cases which are not adiabatic (in the quantum mechanical sense), transition state theory, which is essentially an adiabatic theory of reaction rates, does not permit inclusion of the effect. This effect can be expected to be of greater importance in cases of catalysis by structures, such as enzymes, containing large numbers of vibrational degrees of freedom (particularly low frequency ones) than in cases lacking such structures. The stochastic theory is more general than the transition state theory, the rate constant expression given by the latter being obtainable from the former when restrictive assumptions, including that of adiabaticity, are made. Interpretations of enzyme catalysis based on the transition state theory must thus be viewed as speculative.


Asunto(s)
Enzimas/metabolismo , Cinética , Matemática , Modelos Biológicos , Termodinámica
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