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1.
J Quant Spectrosc Radiat Transf ; 186: 17-39, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32817995

RESUMO

TEMPO was selected in 2012 by NASA as the first Earth Venture Instrument, for launch between 2018 and 2021. It will measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO observes from Mexico City, Cuba, and the Bahamas to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution (~2.1 km N/S×4.4 km E/W at 36.5°N, 100°W). TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry, as well as contributing to carbon cycle knowledge. Measurements are made hourly from geostationary (GEO) orbit, to capture the high variability present in the diurnal cycle of emissions and chemistry that are unobservable from current low-Earth orbit (LEO) satellites that measure once per day. The small product spatial footprint resolves pollution sources at sub-urban scale. Together, this temporal and spatial resolution improves emission inventories, monitors population exposure, and enables effective emission-control strategies. TEMPO takes advantage of a commercial GEO host spacecraft to provide a modest cost mission that measures the spectra required to retrieve ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), formaldehyde (H2CO), glyoxal (C2H2O2), bromine monoxide (BrO), IO (iodine monoxide),water vapor, aerosols, cloud parameters, ultraviolet radiation, and foliage properties. TEMPO thus measures the major elements, directly or by proxy, in the tropospheric O3 chemistry cycle. Multi-spectral observations provide sensitivity to O3 in the lowermost troposphere, substantially reducing uncertainty in air quality predictions. TEMPO quantifies and tracks the evolution of aerosol loading. It provides these near-real-time air quality products that will be made publicly available. TEMPO will launch at a prime time to be the North American component of the global geostationary constellation of pollution monitoring together with the European Sentinel-4 (S4) and Korean Geostationary Environment Monitoring Spectrometer (GEMS) instruments.

2.
Nature ; 448(7157): 1026-8, 2007 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-17728752

RESUMO

Class 0 protostars, the youngest type of young stellar objects, show many signs of rapid development from their initial, spheroidal configurations, and therefore are studied intensively for details of the formation of protoplanetary disks within protostellar envelopes. At millimetre wavelengths, kinematic signatures of collapse have been observed in several such protostars, through observations of molecular lines that probe their outer envelopes. It has been suggested that one or more components of the proto-multiple system NGC 1333-IRAS 4 (refs 1, 2) may display signs of an embedded region that is warmer and denser than the bulk of the envelope. Here we report observations that reveal details of the core on Solar System dimensions. We detect in NGC 1333-IRAS 4B a rich emission spectrum of H2O, at wavelengths 20-37 microm, which indicates an origin in extremely dense, warm gas. We can model the emission as infall from a protostellar envelope onto the surface of a deeply embedded, dense disk, and therefore see the development of a protoplanetary disk. This is the only example of mid-infrared water emission from a sample of 30 class 0 objects, perhaps arising from a favourable orientation; alternatively, this may be an early and short-lived stage in the evolution of a protoplanetary disk.

3.
J Vocat Rehabil ; 33(3): 181-192, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-21818173

RESUMO

Employment difficulties are common among American Indian individuals in substance abuse treatment. To address this problem, the Southwest Node of NIDA's Clinical Trials Network conducted a single-site adaptation of its national Job Seekers Workshop study in an American Indian treatment program, Na'Nizhoozhi Center (NCI). 102 (80% men, 100% American Indian) participants who were in residential treatment and currently unemployed were randomized to (1) a three session, manualized program (Job seekers workshop: JSW) or (2) a 40-minute Job Interviewing Video: JIV). Outcomes were assessed at 3-month follow up: 1) number of days to a new taxed job or enrollment in a job-training program, and 2) total hours working or enrolled in a job-training program. No significant differences were found between the two groups for time to a new taxed job or enrollment in a job-training program. There were no significant differences between groups in substance use frequency at 3-month follow-up. These results do not support the use of the costly and time-consuming JSW intervention in this population and setting. Despite of the lack of a demonstrable treatment effect, this study established the feasibility of including a rural American Indian site in a rigorous CTN trial through a community-based participatory research approach.

4.
Science ; 164(3885): 1271-3, 1969 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-17772564

RESUMO

We have flown a telescope cooled to liquid-helium temperatures and made far-infrared observations of the night sky. A gallium-doped germanium detector, sensitive from 5.2 to 130 micrometers, detected a minimum signal of 10(-9) watt per square centimeter per steradian referred to 100 micrometers. The origin of this signal can be instrumental, atmospheric, interplanetary, or interstellar. We can place a firm upper limit on the color temperature of a dilute cosmic background flux.

5.
Science ; 161(3848): 1361-2, 1968 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-4299808

RESUMO

Confluent monolayers of either mouse or diploid human fibroblasts contained no measurable amounts of either collagenolytic (pH 5.5) or proteolytic (pH 7.5) activities. Within a few hours after exposure of these cells to antiinflammatory drugs, significant amounts of these enzymatic activities were demonstrable extracellularly. These activities were profoundly decreased in cultures simultaneously treated with the anti-inflammatory drugs and cycloheximide or actinomycin D.


Assuntos
Cicloeximida/farmacologia , Dactinomicina/farmacologia , Indução Enzimática , Fibroblastos/enzimologia , Hidrocortisona/farmacologia , Indometacina/farmacologia , Células L , Colagenase Microbiana/biossíntese , Oxifenilbutazona/farmacologia , Peptídeo Hidrolases/biossíntese , Animais , Colágeno/metabolismo , Diploide , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Ratos , Estimulação Química
6.
Science ; 173(4002): 1139-41, 1971 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-5098956

RESUMO

A specific endogenous inhibitor for lymphocyte DNA synthesis that can be isolated from the lymphoid system and which is probably cell specific is described. The inhibitor is thermolabile, is destroyed by trypsin, and has a mass of about 30,000 to 50,000 daltons.


Assuntos
DNA/biossíntese , Linfócitos/metabolismo , Tecido Linfoide/análise , Animais , Isótopos de Carbono , Bovinos , Criança , Fibroblastos/metabolismo , Células HeLa/metabolismo , Humanos , Lectinas/farmacologia , Leucemia Linfoide/metabolismo , Linfonodos/análise , Linfócitos/efeitos dos fármacos , Peso Molecular , Fenilalanina/metabolismo , Ratos , Baço/análise , Timidina/metabolismo , Timo/análise , Extratos de Tecidos/farmacologia , Trítio , Uridina/metabolismo
7.
Science ; 189(4207): 997-9, 1975 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-17789157

RESUMO

The skeletons of living specimens of the scleractinian coral Porites lobata have been found to contain up to 46 +/- 5 percent low-magnesium calcite even though free of gross detrital inclusions and boring or encrusting organisms. The calcite crystals occur in the interior of skeletal structures, have dimensions of 20 micrometers or less, and are surrounded by typical aragonite needles. Biogenic deposition seems to be the most likely source of the calcite, although the evidence does not rule out diagenesis of metastable.

8.
Science ; 204(4391): 404-7, 1979 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17758014

RESUMO

The strontium to calcium ratio of skeletal aragonite in three genera of reef-building corals varies as a simple function of temperature and the strontium to calcium ratio of the incubation water. The strontiumlcalcium distribution coefficients of coral aragonite apparently differ from the corresponding coefficient of inorganically precipitated aragonite. With some care, coral skeletons can be used as recording thermometers.

9.
Science ; 194(4267): 844-6, 1976 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-982046

RESUMO

Cultures of L-929 and WI-38 cells, frozen to 4.2 degrees K and exposed for 4 to 8 hours to 5000-oersted magnetic fields, were markedly inhibited in their growth as compared to controls. In cultures grown on cover slips, approximately 7 days after exposure, morphologically distinct cells emerged and were propagated from generation to generation; 3 weeks later, in flask cultures, contact inhibition was abolished. It is concluded that under certain experimental conditions, strong magnetic fields induce morphological and physiological transformations of target cells.


Assuntos
Divisão Celular , Inibição de Contato , Magnetismo , Linhagem Celular , Eletricidade , Células L , Temperatura
10.
Science ; 207(4426): 78-80, 1980 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-7350643

RESUMO

Acid extract of human placental tissue contain, by both radioimmunoassay and radioreceptor assay, beta-endrophin-like material. Half of this material will not go through a 5000-dalton filter and on Sephadex G-200 has a molecular size between 25,00 and 50,000 daltons. Of the material going through a 5000-dalton ultrafilter, 80 percent is excluded on Sephadex G-25 and held back, very slightly, on Bio-Rad P6, indicating a molecular size of approximately 4500 to 4800 daltons. Thus, placenta appears to have macromolecular precursors from which a beta-endorphin-like material is released, with a size approximately 12 amino acids longer than half of the pituitary hormone.


Assuntos
Endorfinas/metabolismo , Placenta/metabolismo , Feminino , Humanos , Peso Molecular , Gravidez , Radioimunoensaio , Ensaio Radioligante
11.
Science ; 189(4204): 720-2, 1975 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-17792540

RESUMO

Spectral measurements of the thermal radiation from Jupiter in the band from 16 to 40 micrometers are analyzed under the assumption that pressure-broadened molecular hydrogen transitions are responsible for the bulk of the infrared opacity over most of this spectral interval. Both the vertical pressure-temperature profile and the molecular hydrogen mixing ratio are determined. The derived value ofthe molecular hydrogen mixing ratio, 0.89 +/- 0.11, is consistent with the solar value of 0.86.

12.
Science ; 196(4292): 896-7, 1977 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-140460

RESUMO

Experiments with lymphocyte and fibroblast chalones indicate that they are complexed strongly with RNA in tissue extracts; have a molecular weight of less than 10,000 and more than 1,000 daltons, and probably about 5,000 daltons; are strongly cationically charged; and contain mannose and perhaps other carbohydrates.


Assuntos
Fibroblastos , Inibidores do Crescimento , Linfócitos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Glicopeptídeos/análise , Inibidores do Crescimento/isolamento & purificação , Inibidores do Crescimento/farmacologia , Ponto Isoelétrico , Linfócitos/efeitos dos fármacos , Manose/análise , Peso Molecular , RNA/metabolismo
13.
Science ; 231(4740): 807-14, 1986 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17774074

RESUMO

The 250,000 sources in the recently issued Infrared Astronomy Satellite (IRAS) all-sky infrared catalog are a challenge to astronomy. Many of these sources will be studied with existing and planned ground-based and airborne telescopes, but many others can no longer even be detected now that IRAS has ceased to operate. As anticipated by advisory panels of the National Academy of Sciences for a decade, study of the IRAS sources will require the Space Infrared Telescope Facility (SIRTF), a cooled, pointed telescope in space. This instrument may be the key to our understanding of cosmic birth-the formation of planets, stars, galaxies, active galactic nuclei, and quasars. Compared with IRAS and existing telescopes, SIRTF's power derives from a thousandfold gain in sensitivity over five octaves of the spectrum.

14.
Science ; 224(4644): 14-21, 1984 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-17783499

RESUMO

For 10 months the Infrared Astronomical Satellite (IRAS) provided astronomers with what might be termed their first view of the infrared sky on a clear, dark night. Without IRAS, atmospheric absorption and the thermal emission from both the atmosphere and Earthbound telescopes make the task of the infrared astronomer comparable to what an optical astronomer would face if required to work only on cloudy afternoons. IRAS observations are serving astronomers in the same manner as the photographic plates of the Palomar Observatory Sky Survey; just as the optical survey has been used by all astronomers for over three decades, as a source of quantitative information about the sky and as a "roadmap" for future observations, the results of IRAS will be studied for years to come. IRAS has demonstrated the power of infrared astronomy from space. Already, from a brief look at a miniscule fraction of the data available, we have learned much about the solar system, about nearby stars, about the Galaxy as a whole and about distant extragalactic systems. Comets are much dustier than previously thought. Solid particles, presumably the remnants of the star-formation process, orbit around Vega and other stars and may provide the raw material for planetary systems. Emission from cool interstellar material has been traced throughout the Galaxy all the way to the galactic poles. Both the clumpiness and breadth of the distribution of this material were previously unsuspected. The far-infrared sky away from the galactic plane has been found to be dominated by spiral galaxies, some of which emit more than 50 percent and as much as 98 percent of their energy in the infrared-an exciting and surprising revelation. The IRAS mission is clearly the pathfinder for future missions that, to a large extent, will be devoted to the discoveries revealed by IRAS.

15.
Schizophr Res ; 209: 129-134, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31130399

RESUMO

An investigation of differences in dynamic functional network connectivity (dFNC) of healthy controls (HC) versus that of schizophrenia patients (SP) was completed, using eyes-open resting state MEG data. The MEG analysis utilized a source-space activity estimate (MNE/dSPM) whose result was the input to a group spatial independent component analysis (ICA), on which the networks of our MEG dFNC analysis were based. We have previously reported that our MEG dFNC revealed that SP change between brain meta-states (repeating patterns of network correlations which are allowed to overlap in time) significantly more often and to states which are more different, relative to HC. Here, we extend our previous work to investigate the relationship between symptomology in SP and four meta-state metrics. We found a significant correlation between positive symptoms and the two meta-state metrics which showed significant differences between HC and SP. These two statistics quantified 1) how often individuals change state and 2) the total distance traveled within the state-space. We additionally found that a clustering of the meta-state metrics divides SP into groups which vary in symptomology. These results indicate specific relationships between symptomology and brain function for SP.


Assuntos
Encéfalo/fisiopatologia , Magnetoencefalografia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Adulto Jovem
16.
J Frailty Aging ; 7(1): 51-56, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29412443

RESUMO

BACKGROUND: Muscle mass deficits endure after hip fracture. Strategies to improve muscle quality may improve mobility and physical function. It is unknown whether training after usual care yields muscle quality gains after hip fracture. OBJECTIVES: To determine whether muscle quality improves after hip fracture with high-intensity resistance training and protein supplementation. DESIGN: Case series. SETTING: University of Utah Skeletal Muscle Exercise Research Facility. PARTICIPANTS: 17 community-dwelling older adults, 3.6+/-1.1 months post-hip fracture, recently discharged from usual-care physical therapy (mean age 77.0+/-12.0 years, 12 female), enrolled. INTERVENTION: Participants underwent 12 weeks (3x/week) of unilaterally-biased resistance training. METHODS/MATERIALS: Participants were measured via a 3.0 Tesla whole-body MR imager for muscle lean and intramuscular adipose tissue (IMAT) of the quadriceps before and after resistance training. Peak isometric knee extension force output was measured with an isokinetic dynamometer. Muscle quality was calculated by dividing peak isometric knee extension force (N) by quadriceps lean muscle mass (cm2). In addition, common physical function variables were measured before and after training. RESULTS: Surgical and nonsurgical lean quadriceps muscle mass improved among participants (mean change: 2.9 cm2+/-1.4 cm2, and 2.7 cm2+/-1.3 cm2, respectively), while IMAT remained unchanged. Peak force improved in the surgical limb by 43.1+/-23N, with no significant change in the nonsurgical limb. Significant gains in physical function were evident after training. CONCLUSION: Participants recovering from hip fracture demonstrated improvements in muscle mass, muscle strength, and muscle quality in the surgical limb after hip fracture. These were in addition to gains made in the first months after fracture with traditional care. Future studies should determine the impact that muscle quality has on long-term functional recovery in this population.


Assuntos
Fraturas do Quadril/reabilitação , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Idoso , Feminino , Avaliação Geriátrica , Humanos , Imageamento por Ressonância Magnética , Masculino , Modalidades de Fisioterapia , Recuperação de Função Fisiológica , Resultado do Tratamento
17.
J Nutr Health Aging ; 22(3): 431-438, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29484358

RESUMO

OBJECTIVES: Post rehabilitation, older adults with hip fracture display low vertical ground reaction force (vGRF) on the involved lower extremity during a sit-to-stand task and low physical function. The purpose of this study was to test whether muscle performance, involved side vGRF during a sit-to-stand task, and physical function improved following multimodal high-intensity resistance training, when initiated after usual care (2 to 6 months after hip fracture). DESIGN: Case series study, 12 weeks extended high-intensity strength training intervention following hip fracture. SETTING: University hospital outpatient facility. PARTICIPANTS: Twenty-four community-dwelling older adults (mean age 78.4 years (SD 10.4), 16 female/8 male), 3.6 (SD 1.2) months post-hip fracture and discharged from physical therapy participated. Intervention/Measurement: All participants performed sit-to-stand tasks, muscle performance tests, and modified physical performance test (mPPT) before and after 12 weeks (3x/wk) of training. Variables were compared using paired t-tests. RESULTS: The vGRF rate of force development (RFD) and magnitude of discrepancy between limb loading during rising phase of sit-to-stand task (AREA) variables improved post-training (RFD ratio = Pre: 0.78 - Post: 0.82, AREA ratio = Pre: 0.79 - Post: 0.86). Surgical leg extension power gains were large (~65%) while strength gains were moderate (~34%); yielding improved symmetry in both strength (Pre: 0.74 - Post: 0.88) and power (Pre: 0.75 - Post: 0.82). Physical function improved pre-training 25 (SD 5.2) to post training 30 (SD 4.3), (p < 0.001). CONCLUSION: Unique to this study, participants recovering from hip fracture demonstrated improved symmetry in sit-to-stand vGRFs, muscle function, and physical function after training. However, a high percentage of patients continued to experience persistently low vGRF of the involved side compared to previous studies of healthy elderly controls. Developing alternative strategies to improve involved side vGRF may be warranted.


Assuntos
Fraturas do Quadril/fisiopatologia , Fraturas do Quadril/reabilitação , Força Muscular/fisiologia , Modalidades de Fisioterapia , Amplitude de Movimento Articular/fisiologia , Treinamento Resistido/métodos , Idoso , Feminino , Humanos , Extremidade Inferior/fisiologia , Masculino
18.
Rev Sci Instrum ; 78(1): 011302, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17503900

RESUMO

The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991-2000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.


Assuntos
Astronomia/instrumentação , Meio Ambiente Extraterreno , Voo Espacial , United States National Aeronautics and Space Administration , Astronomia/história , História do Século XX , História do Século XXI , Voo Espacial/história , Voo Espacial/instrumentação , Estados Unidos , United States National Aeronautics and Space Administration/história
19.
Neuroinformatics ; 15(4): 343-364, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28812221

RESUMO

In this paper we describe an open-access collection of multimodal neuroimaging data in schizophrenia for release to the community. Data were acquired from approximately 100 patients with schizophrenia and 100 age-matched controls during rest as well as several task activation paradigms targeting a hierarchy of cognitive constructs. Neuroimaging data include structural MRI, functional MRI, diffusion MRI, MR spectroscopic imaging, and magnetoencephalography. For three of the hypothesis-driven projects, task activation paradigms were acquired on subsets of ~200 volunteers which examined a range of sensory and cognitive processes (e.g., auditory sensory gating, auditory/visual multisensory integration, visual transverse patterning). Neuropsychological data were also acquired and genetic material via saliva samples were collected from most of the participants and have been typed for both genome-wide polymorphism data as well as genome-wide methylation data. Some results are also presented from the individual studies as well as from our data-driven multimodal analyses (e.g., multimodal examinations of network structure and network dynamics and multitask fMRI data analysis across projects). All data will be released through the Mind Research Network's collaborative informatics and neuroimaging suite (COINS).


Assuntos
Neuroimagem/métodos , Esquizofrenia/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Disseminação de Informação , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino
20.
J Natl Cancer Inst ; 56(5): 899-902, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-136520

RESUMO

The molecular weight fractions of 10,000-50,000 daltons prepared from "used" medium obtained during cultivation of human colon carcinoma cells (SW-48) in vitro inhibited the proliferation and DNA synthesis of these cells. Fractions exceeding 50,000 daltons were not inhibitory; those less than 10,000 daltons were cytotoxic. The inhibitory fraction did not affect either proliferation of human fibroblasts or transformation of human lymphocytes in vitro. Similar fractions from the colon mucosa of other species inhibited the proliferation of SW-48 cells, whereas extracts of dog jejunum or lung did not. This mitotic inhibition was completely reversible and could be destroyed by preincubation with trypsin. Therefore, colon cells appear to contain a cell- (but not species) specific, endogenous mitotic inhibitor or chalone.


Assuntos
Neoplasias do Colo/análise , Inibidores do Crescimento/isolamento & purificação , Animais , Bovinos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Quimotripsina/farmacologia , Meios de Cultura , DNA de Neoplasias/biossíntese , Cães , Fibroblastos/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Humanos , Linfócitos/efeitos dos fármacos , Peso Molecular , Ribonucleases/farmacologia , Suínos , Tripsina/farmacologia
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