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1.
Appl Opt ; 56(18): 5274-5294, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047582

RESUMO

The Cassini spacecraft orbiting Saturn carries the composite infrared spectrometer (CIRS) designed to study thermal emission from Saturn and its rings and moons. CIRS, a Fourier transform spectrometer, is an indispensable part of the payload providing unique measurements and important synergies with the other instruments. It takes full advantage of Cassini's 13-year-long mission and surpasses the capabilities of previous spectrometers on Voyager 1 and 2. The instrument, consisting of two interferometers sharing a telescope and a scan mechanism, covers over a factor of 100 in wavelength in the mid and far infrared. It is used to study temperature, composition, structure, and dynamics of the atmospheres of Jupiter, Saturn, and Titan, the rings of Saturn, and surfaces of the icy moons. CIRS has returned a large volume of scientific results, the culmination of over 30 years of instrument development, operation, data calibration, and analysis. As Cassini and CIRS reach the end of their mission in 2017, we expect that archived spectra will be used by scientists for many years to come.

3.
J Radiol Prot ; 35(3): 507-15, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26083976

RESUMO

In recent years there has been growing interest in the use of neutron scanning techniques for security. Neutron techniques with a range of energy spectra including thermal, white and fast neutrons have been shown to work in different scenarios. As international interest in neutron scanning increases the risk of activating cargo, especially foodstuffs must be considered. There has been a limited amount of research into the activation of foods by neutron beams and we have sought to improve the amount of information available. In this paper we show that for three important metrics; activity, ingestion dose and Time to Background there is a strong dependence on the food being irradiated and a weak dependence on the energy of irradiation. Previous studies into activation used results based on irradiation of pharmaceuticals as the basis for research into activation of food. The earlier work reports that (24)Na production is the dominant threat which motivated the search for (24)Na(n,γ)(24)Na in highly salted foods. We show that (42)K can be more significant than (24)Na in low sodium foods such as Bananas and Potatoes.


Assuntos
Comércio , Inocuidade dos Alimentos , Alimentos/efeitos da radiação , Nêutrons , Cacau/efeitos da radiação , Queijo/efeitos da radiação , Contaminação Radioativa de Alimentos/prevenção & controle , Método de Monte Carlo , Musa/efeitos da radiação , Oryza/efeitos da radiação , Prunus dulcis/efeitos da radiação , Doses de Radiação , Risco , Solanum tuberosum/efeitos da radiação , Zea mays/efeitos da radiação
4.
Science ; 293(5537): 2084-7, 2001 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11557891

RESUMO

Transcription factor TFIID, composed of TBP and TAFII subunits, is a central component of the RNA polymerase II machinery. Here, we report that the tissue-selective TAFII105 subunit of TFIID is essential for proper development and function of the mouse ovary. Female mice lacking TAFII105 are viable but infertile because of a defect in folliculogenesis correlating with restricted expression of TAFII105 in the granulosa cells of the ovarian follicle. Gene expression profiling has uncovered a defective inhibin-activin signaling pathway in TAFII105-deficient ovaries. Together, these studies suggest that TAFII105 mediates the transcription of a subset of genes required for proper folliculogenesis in the ovary and establishes TAFII105 as a cell type-specific component of the mammalian transcriptional machinery.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células da Granulosa/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Ovário/fisiologia , Fatores Associados à Proteína de Ligação a TATA , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Células da Granulosa/metabolismo , Hibridização In Situ , Infertilidade Feminina , Masculino , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Tamanho do Órgão , Especificidade de Órgãos , Ovário/citologia , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Ovulação , Subunidades Proteicas , Transdução de Sinais , Fator de Transcrição TFIID , Fatores de Transcrição/genética , Fatores de Transcrição TFII/metabolismo
5.
Appl Radiat Isot ; 110: 224-229, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26749562

RESUMO

The use of neutrons for cargo interrogation has the potential to drastically improve threat detection. Previous research has focussed on the production of (24)Na, based on the isotopes produced in pharmaceuticals and medical devices. For both the total activity and the ingestion dose we show that a variety of isotopes contribute and that (24)Na is only dominant under certain conditions. The composition of the foods has a strong influence on the resulting activity and ingestion dose suggesting that the pharmaceuticals and medical devices considered initially are not a viable analogue for foodstuffs. There is an energy dependence to the isotopes produced due to the cross-sections of different reactions varying with neutron energy. We show that this results in different isotopes dominating the ingestion dose at different energies, which has not been considered in the previous literature.


Assuntos
Nêutrons Rápidos/efeitos adversos , Irradiação de Alimentos/efeitos adversos , Radioisótopos/análise , Simulação por Computador , Crime/prevenção & controle , Alimentos/efeitos da radiação , Análise de Alimentos , Humanos , Radioisótopos de Sódio/efeitos adversos , Radioisótopos de Sódio/análise , Terrorismo/prevenção & controle
6.
Gene ; 242(1-2): 1-13, 2000 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-10721692

RESUMO

Synthesis of messenger RNA by RNA polymerase II requires the combined activities of more than 70 polypeptides. Coordinating the interaction of these proteins is the basal transcription factor TFIID, which recognizes the core promoter and supplies a scaffolding upon which the rest of the transcriptional machinery can assemble. A multisubunit complex, TFIID consists of the TATA-binding protein (TBP) and several TBP-associated factors (TAFs), whose primary sequences are well-conserved from yeast to humans. Data from reconstituted cell-free transcription systems and binary interaction assays suggest that the TAF subunits can function as promoter-recognition factors, as coactivators capable of transducing signals from enhancer-bound activators to the basal machinery, and even as enzymatic modifiers of other proteins. Whether TAFs function similarly in vivo, however, has been an open question. Initial characterization of yeast bearing mutations in particular TAFs seemingly indicated that, unlike the situation in vitro, TAFs played only a minor role in transcriptional regulation in vivo. However, reconsideration of this data in light of more recent results from yeast and other organisms reveals considerable convergence between the models derived from in vitro experiments and those derived from in vivo studies. In particular, there is an emerging consensus that TAFs represent one of several classes of coactivators that participate in transcriptional activation in vivo.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Fatores de Transcrição TFII/fisiologia , Fatores de Transcrição/fisiologia , Animais , Humanos , Modelos Biológicos , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/genética , Proteína de Ligação a TATA-Box , Fator de Transcrição TFIID , Ativação Transcricional
7.
Gene ; 172(2): 199-205, 1996 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-8682303

RESUMO

From libraries made from activated mouse T lymphocytes, we have isolated cDNAs encoding Wnt-10B, a new member of the Wnt family of developmental control genes. This protein appears to be the mammalian orthologue of Wnt-10B, first identified in several non-mammalian vertebrates and recently in mouse. The mRNA expression pattern of mouse Wnt-10B indicates that it is induced following activation of helper T cells, but is also expressed in a variety of other tissues and cells of fetal or adult origin. 93 bp at the 5' end of the cDNA clone are identical to sequences previously reported as 3' flanking genomic DNA adjacent to a mouse mammary tumor virus (MMTV) provirus in the MMTV-induced BR6 mammary tumor, W26. Sequence analysis of tumor-derived genomic DNA confirms that the entire Wnt-10B gene is immediately adjacent to the provirus, suggesting that MMTV integration drives transcription of Wnt-10B, possibly contributing to the oncogenic process. Consistent with this idea is the detection of hybrid MMTV-Wnt-10B transcripts in BR6 tumor cells. T cells which produce abundant Wnt-10B mRNA were also found to produce protein.


Assuntos
Neoplasias Mamárias Animais/genética , Oncogenes , Proteínas Proto-Oncogênicas/genética , Células Th1/metabolismo , Células Th2/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Células Clonais , Expressão Gênica , Humanos , Vírus do Tumor Mamário do Camundongo/genética , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Provírus/genética , Proteínas Recombinantes de Fusão/genética , Células Th1/citologia , Células Th2/citologia
8.
J Neuroimmunol ; 52(1): 9-17, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8207122

RESUMO

To investigate the potential role of cytokines in the development of the central nervous system, we analyzed the production of cytokine mRNA transcripts by S1-nuclease protection analysis in the brains of Swiss-Webster mice during fetal development and after birth. Cytokines studied were interleukin (IL)-1 alpha, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, macrophage-colony stimulating factor (M-CSF), granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage-colony stimulating factor (GM-CSF), and leukemia inhibitory factor (LIF). Only mRNA transcripts for M-CSF were found to be produced constitutively in normal brain tissue. These transcripts were detected continuously from embryonic day (ED) 13 through adulthood. Transcripts encoding the M-CSF receptor (c-fms) were also detected at all of these time points. Despite identification of M-CSF transcripts in the brains of normal mice during development and M-CSF protein in cell cultures, neuropathological examination of the brains of op/op mice, a naturally occurring mouse mutant defective in the production of functional M-CSF, showed no cytoarchitectural abnormalities.


Assuntos
Encéfalo/metabolismo , Fator Estimulador de Colônias de Macrófagos/biossíntese , Receptor de Fator Estimulador de Colônias de Macrófagos/biossíntese , Fatores Etários , Animais , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Citocinas/biossíntese , Feminino , Fator Estimulador de Colônias de Macrófagos/genética , Fator Estimulador de Colônias de Macrófagos/fisiologia , Camundongos , Osteopetrose/metabolismo , Gravidez , RNA Mensageiro/análise
9.
Am J Med Genet ; 51(4): 294-7, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7942990

RESUMO

A 2-year-old boy with manifestations of the fragile X syndrome was found to have a cytogenetically visible deletion of Xq27-q28 including deletion of FMR-1. Molecular analysis of the patient was recently described in Tarleton et al. [1993: Hum Mol Genet 2(11): 1973-1974] and the deletion was estimated to be at least 3 megabases (Mb). His mother had 2 FMR-1 alleles with normal numbers of CGG repeats, 20 and 32, respectively. Thus, the deletion occurred as a de novo event. The patient does not appear to have clinical or laboratory findings other than those typically associated with fragile X syndrome, suggesting that the deletion does not remove other contiguous genes. This report describes the phenotype of the patient, including psychological studies.


Assuntos
Síndrome do Cromossomo X Frágil/genética , Deleção de Genes , Fragilidade Cromossômica , Humanos , Lactente , Cariotipagem , Masculino , Fenótipo
10.
Obstet Gynecol ; 76(5 Pt 2): 949-51, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2216262

RESUMO

A 25-year-old primigravida delivered monozygotic twins discordant for multiple anomalies and partial trisomy 1 mosaicism. The phenotype of partial trisomy 1 includes craniofacial, central nervous system, and ocular anomalies. The most likely explanation for these findings is that the translocation occurred after twinning occurred. This observation emphasizes that monozygotic twins are not necessarily genetically identical. They are identical at conception, but subsequent mutation and rearrangement of the genome may cause substantial phenotypic differences.


Assuntos
Anormalidades Múltiplas/genética , Cromossomos Humanos Par 1 , Doenças em Gêmeos/genética , Trissomia , Gêmeos Monozigóticos/genética , Adulto , Feminino , Humanos , Recém-Nascido , Cariotipagem , Masculino , Mosaicismo/genética , Fenótipo , Gravidez , Translocação Genética/genética , Cromossomo Y
11.
Obstet Gynecol ; 76(5 Pt 2): 969-71, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1699188

RESUMO

Two cases of congenital nephrosis were detected through routine maternal serum alpha-fetoprotein (MSAFP) screening of 95,135 patients. No other cases of congenital nephrosis from this group were reported, resulting in an incidence of approximately one in 47,500 in this low-risk population. In both of these cases, similar to other reported cases of congenital nephrosis having MSAFP screening, the protein concentrations were greater than or equal to 10 multiples of the median (MOM). Therefore, in the case of an MSAFP over 10 MOM and a normal ultrasound examination, congenital nephrosis should be included in counseling regarding the possibility of undetected malformations. Furthermore, in the case of a pregnancy with elevated amniotic fluid AFP with negative acetylcholinesterase and normal ultrasound, the possibility of congenital nephrosis should be mentioned, regardless of family history or ancestry. When a pregnancy is terminated because of these biochemical findings, special and immediate attention to the fetal kidneys using electron microscopy is necessary to evaluate properly the possibility of congenital nephrosis.


Assuntos
Doenças Fetais/prevenção & controle , Nefrose/congênito , Diagnóstico Pré-Natal , alfa-Fetoproteínas/análise , Feminino , Humanos , Recém-Nascido , Funções Verossimilhança , Programas de Rastreamento , Nefrose/prevenção & controle , Gravidez , Fatores de Risco
12.
Obstet Gynecol ; 71(2): 203-7, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2447540

RESUMO

We reviewed our experience with a policy of revising the estimated probability of an open neural tube defect for those cases in which maternal serum alpha-fetoprotein (MSAFP) was elevated and the ultrasound examination was normal. Assuming a sensitivity for the ultrasound diagnosis of neural tube defects of 90%, the risk estimate derived from the MSAFP was reduced by that amount when ultrasound was adequate and normal. When counseled regarding this revised risk estimate, 67% of our patients declined amniocentesis. The sensitivity for the ultrasound diagnosis of anencephaly in our series was 100%; for open spine defects, 80%; and for all open neural tube defects, 91%. The two patients in whom an open spine defect was not detected with ultrasound had elevated revised risk estimates. When appropriate criteria are met, the estimated sensitivity of ultrasound in diagnosing open neural tube defects may be used for counseling patients at risk for a fetus with an open neural tube defect.


Assuntos
Amniocentese , Defeitos do Tubo Neural/diagnóstico , Diagnóstico Pré-Natal , Ultrassonografia , alfa-Fetoproteínas/análise , Líquido Amniótico/análise , Anencefalia/diagnóstico , Árvores de Decisões , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez
13.
Obstet Gynecol ; 72(3 Pt 1): 337-41, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2457190

RESUMO

Nineteen pregnancies evaluated for elevated maternal serum alpha-fetoprotein levels were found to have moderate to severe oligohydramnios. There were no survivors among six fetuses with ultrasound-diagnosed urinary tract anomalies. We followed 11 of the remaining 13 pregnancies with serial ultrasound examinations. When the second ultrasound examination demonstrated severely decreased amniotic fluid, the outcome was always poor (intrauterine death, perinatal death, or fetal deformations). Of the five cases in which the second ultrasound showed normal to moderately decreased fluid, there were four surviving infants. When no primary malformations are seen on the initial ultrasound examination, serial ultrasound evaluations of amniotic fluid volume help predict the pregnancy outcome.


Assuntos
Líquido Amniótico/análise , Doenças Fetais/diagnóstico , Resultado da Gravidez/sangue , Diagnóstico Pré-Natal , Ultrassonografia , alfa-Fetoproteínas/análise , Aborto Induzido , Estudos de Avaliação como Assunto , Feminino , Doenças Fetais/sangue , Humanos , Rim/anormalidades , Gravidez , Segundo Trimestre da Gravidez , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Obstrução Uretral/sangue , Obstrução Uretral/diagnóstico
14.
IEEE Trans Biomed Eng ; 47(7): 902-10, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10916261

RESUMO

The control interface is one of the most critical components of the electric-powered wheelchair (EPW). The control interface must accommodate the user's limitations and maximize the user's abilities. This study extended Fitts' Law for target-acquisition to a continuously updated target. The extended Fitts' Law was used to examine EPW driving with a standard position sensing joystick and a prototype isometric joystick (IJ). The extended Fitts' Law provides insight into the difficulty of performing target-acquisition tasks with an EPW. The test results showed significant differences (p < 0.05) among the two types of joysticks for selected measures of information processing capacity, movement time, root-mean-square-error, and average velocity while performing turning maneuvers. The mean values indicate that the IJ may provide superior turning performance.


Assuntos
Cadeiras de Rodas , Algoritmos , Engenharia Biomédica , Eletricidade , Desenho de Equipamento , Humanos
15.
J Rehabil Res Dev ; 32(3): 255-63, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8592297

RESUMO

The range of a power wheelchair depends on many factors including: battery type, battery state, wheelchair/rider weight, terrain, the efficiency of the drive train, and driving behavior. The purpose of this study was to evaluate the feasibility of three methods of estimating power wheelchair range. Another significant purpose was to compare the current draw on pavement to current draw on an International Standards Organization (ISO) Double Drum tester at one m/sec. Tests were performed on seven different power wheelchairs unloaded, and loaded with an ISO 100 kg test dummy. Each chair was configured according to the manufacturer's specifications, and tires were properly inflated. Experienced test technicians were used for the tennis court tests, and treadmill tests. An ISO 100 kg test dummy was used for the ISO Double Drum test. Energy consumption was measured over a distance of 1500 m for each of the three test conditions. The rolling surface was level in all cases. Repeated measure analysis of variance (ANOVA) revealed a significant difference (p = 0.0001) between the predicted range at maximum speed for the three tests. Post hoc analysis demonstrated a significant difference (p < 0.01) in estimated range at maximum speed between the Double Drum test and the treadmill test, as well as between the Double Drum test and the tennis court test. Our results indicate no significant difference (p > 0.05) between the predicted range at maximal speed between the treadmill and tennis court tests. A simple relationship does not exist between the results of range testing with the Double Drum tester and the tennis court. An alternative would be to permit the use of a treadmill for range testing as simple relationships between all pertinent treadmill and tennis court range data were found. For the Double Drum tester used, the current demand is higher than under normal usage. This presents a problem as current is related to load torque in a power wheelchair. Hence, the Double Drum tester friction must be reduced. The predicted range for the tennis court test at maximum speed ranges from a low of 23.6 km to a high of 57.7 km. The range of the power wheelchair can be improved by the use of wet lead acid batteries in place of gel lead acid batteries.


Assuntos
Cadeiras de Rodas , Fontes de Energia Elétrica , Estresse Mecânico
16.
J Rehabil Res Dev ; 33(1): 45-55, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8868417

RESUMO

The proper selection of a wheelchair requires making several critical decisions, not the least of which is what type of wheelchair is appropriate. The International Organization for Standards (ISO) continues to develop and refine wheelchair standards. Standards allow the objective comparison of products from various sources, permitting consumers or clinicians to assess wheelchairs with which they are not familiar by comparing test results. This study consisted of three components: 1) the comparison of fatigue test results with a planar ANSI/RESNA test dummy to a HERL contoured test dummy; 2) the comparison of fatigue test results for common depot versus common rehabilitation manual wheelchairs; and 3) the comparison of fatigue test results for manual rehabilitation wheelchairs with solid 8-inch casters versus those with pneumatic 8-inch casters. Rehabilitation wheelchairs lasted on average 13.2 times longer than the depot wheelchairs. Both types, tested with the standard ISO-ANSI/RESNA dummy, lasted on average 2.1 times longer than those wheelchairs tested using the contoured dummy. The three rehabilitation wheelchairs equipped with 8-inch pneumatic casters lasted on average 3.2 times longer than the 6 rehabilitation wheelchairs equipped with solid 8-inch casters. The depot wheelchairs cost about 3.4 times as much to operate per cycle or per meter than the rehabilitation wheelchairs. The rehabilitation wheelchairs tended to experience component failures, while the depot wheelchairs tended to experience frame failures. Our testing indicates that the tests in the ISO-ANSI/RESNA standards can relate design features to fatigue test results and durability. Rehabilitation wheelchairs tend to use higher quality materials and better manufacturing practices, and they provide greater mobility for wheelchair users. Purchasers and prescribers of wheelchairs should consider the life-cycle cost and not just the purchase price for wheelchairs.


Assuntos
Manuais como Assunto , Reabilitação/instrumentação , Cadeiras de Rodas/economia , Cadeiras de Rodas/normas , Análise de Variância , Segurança de Equipamentos , Humanos , Reabilitação/economia
20.
J Dermatol Surg Oncol ; 9(3): 231-4, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6826878

RESUMO

A prolonged cure of extensive primary and recurrent cancers of the skin by cryosurgery is reported. The patient had involvement of approximately 95 cm2 of her face with carcinomas, primarily of basal-cell type, which had been refractory to all previous x-ray and conventional surgical therapies rendered during a 6-year span. Aggressive cryosurgery utilizing six systematically designed "overlapping fields" of ice blocks was rendered to this entire area during a 1-month period as office surgical procedures under local anesthesia.


Assuntos
Carcinoma Basocelular/cirurgia , Criocirurgia/métodos , Recidiva Local de Neoplasia/cirurgia , Neoplasias Cutâneas/cirurgia , Idoso , Feminino , Humanos , Fatores de Tempo
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