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1.
Space Sci Rev ; 217(1): 24, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33612866

RESUMO

Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission's Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 µrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 µrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory Curiosity rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover's Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover's traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover's sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions.

2.
Space Sci Rev ; 216(8): 137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33268910

RESUMO

The Mars 2020 Perseverance rover is equipped with a next-generation engineering camera imaging system that represents an upgrade over previous Mars rover missions. These upgrades will improve the operational capabilities of the rover with an emphasis on drive planning, robotic arm operation, instrument operations, sample caching activities, and documentation of key events during entry, descent, and landing (EDL). There are a total of 16 cameras in the Perseverance engineering imaging system, including 9 cameras for surface operations and 7 cameras for EDL documentation. There are 3 types of cameras designed for surface operations: Navigation cameras (Navcams, quantity 2), Hazard Avoidance Cameras (Hazcams, quantity 6), and Cachecam (quantity 1). The Navcams will acquire color stereo images of the surface with a 96 ∘ × 73 ∘ field of view at 0.33 mrad/pixel. The Hazcams will acquire color stereo images of the surface with a 136 ∘ × 102 ∘ at 0.46 mrad/pixel. The Cachecam, a new camera type, will acquire images of Martian material inside the sample tubes during caching operations at a spatial scale of 12.5 microns/pixel. There are 5 types of EDL documentation cameras: The Parachute Uplook Cameras (PUCs, quantity 3), the Descent stage Downlook Camera (DDC, quantity 1), the Rover Uplook Camera (RUC, quantity 1), the Rover Descent Camera (RDC, quantity 1), and the Lander Vision System (LVS) Camera (LCAM, quantity 1). The PUCs are mounted on the parachute support structure and will acquire video of the parachute deployment event as part of a system to characterize parachute performance. The DDC is attached to the descent stage and pointed downward, it will characterize vehicle dynamics by capturing video of the rover as it descends from the skycrane. The rover-mounted RUC, attached to the rover and looking upward, will capture similar video of the skycrane from the vantage point of the rover and will also acquire video of the descent stage flyaway event. The RDC, attached to the rover and looking downward, will document plume dynamics by imaging the Martian surface before, during, and after rover touchdown. The LCAM, mounted to the bottom of the rover chassis and pointed downward, will acquire 90 ∘ × 90 ∘ FOV images during the parachute descent phase of EDL as input to an onboard map localization by the Lander Vision System (LVS). The rover also carries a microphone, mounted externally on the rover chassis, to capture acoustic signatures during and after EDL. The Perseverance rover launched from Earth on July 30th, 2020, and touchdown on Mars is scheduled for February 18th, 2021.

3.
Water Sci Technol ; 64(1): 271-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22053485

RESUMO

The present design of stormwater tanks is based on the creation of storage volume to retain stormwater and the prevention or reduction of stormwater overflows. The treatment of stormwater is often improved with mechanical equipment. The general layout rules do usually not include the appropriate choice of design inflow related to the chosen treatment equipment. In the following investigations it was the task to analyze the hydraulic efficiency and the overflow behaviour of a lamella particle separator inside a stormwater tank under different design approaches regarding the chosen design inflow. Therefore six scenarios with different precipitation yield approaches were chosen and applied to a given constant sized catchment to calculate the design inflows. For a given minimum particle size, the necessary number of lamellas were determined for the scenarios and standard stormwater tanks were dimensioned. These stormwater tanks were modelled in the hydrologic model SMUSI to investigate the overflow behaviour of the different tank sizes. The number of overflow events, their duration and maximum flow rates were the results of the modelling. Comparisons to the design inflows were carried out. The treated particles sizes at the overflow events were determined reversible and compared to the original chosen minimum particle sizes.


Assuntos
Tamanho da Partícula , Esgotos , Eliminação de Resíduos Líquidos/métodos , Chuva , Eliminação de Resíduos Líquidos/instrumentação , Movimentos da Água
4.
Appl Environ Microbiol ; 67(9): 3994-4000, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11525996

RESUMO

Attempts were made to engineer the periplasm of Escherichia coli to an expression compartment of heterologous proteins in their native conformation. As a first approach the low-molecular-size additive L-arginine and the redox compound glutathione (GSH) were added to the culture medium. Addition of 0.4 M L-arginine and 5 mM reduced GSH increased the yield of a native tissue-type plasminogen activator variant (rPA), consisting of the kringle-2 and the protease domain, and a single-chain antibody fragment (scFv) up to 10- and 37-fold, respectively. A variety of other medium additives also had positive effects on the yield of rPA. In a second set of experiments, the effects of cosecreted ATP-independent molecular chaperones on the yields of native therapeutic proteins were investigated. At optimized conditions, cosecretion of E. coli DnaJ or murine Hsp25 increased the yield of native rPA by a factor of 170 and 125, respectively. Cosecretion of DnaJ also dramatically increased the amount of a second model protein, native proinsulin, in the periplasm. The results of this study are anticipated to initiate a series of new approaches to increase the yields of native, disulfide-bridged, recombinant proteins in the periplasm of E. coli.


Assuntos
Dissulfetos/metabolismo , Escherichia coli/metabolismo , Chaperonas Moleculares/metabolismo , Periplasma/metabolismo , Proteínas Recombinantes/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Meios de Cultura , Escherichia coli/genética , Proteínas de Escherichia coli , Glutationa/metabolismo , Proteínas de Choque Térmico HSP40 , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Plasmídeos , Proinsulina/genética , Proinsulina/metabolismo , Ativador de Plasminogênio Tecidual/genética
5.
J Nurs Adm ; 29(9): 43-50, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10491668

RESUMO

An integrated healthcare delivery system requires a consistent patient care delivery model. The authors describe the process used to define common elements of the patient care model. These elements include the roles of chief nurse executives, first-line managers, staff registered nurses, and unlicensed assistive personnel. In addition, the philosophy of nursing and support functions (staff education and nursing dashboard for quality measurement) in place across the system are discussed.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Modelos de Enfermagem , Serviço Hospitalar de Enfermagem/organização & administração , Chicago , Humanos , Illinois , Capacitação em Serviço , Enfermeiros Administradores/organização & administração , Assistentes de Enfermagem/organização & administração , Cuidados de Enfermagem/normas , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Filosofia em Enfermagem , Qualidade da Assistência à Saúde
7.
Biochim Biophys Acta ; 1385(2): 221-8, 1998 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-9655909

RESUMO

Activation of the coenzyme ThDP was studied by measuring the kinetics of deprotonation at the C2 carbon of thiamin diphosphate in the enzymes pyruvate decarboxylase, transketolase, pyruvate dehydrogenase complex, pyruvate oxidase, in site-specific mutant enzymes and in enzyme complexes containing coenzyme analogues by proton/deuterium exchange detected by 1H-NMR spectroscopy. The respective deprotonation rate constant is above the catalytic constant in all enzymes investigated. The fast deprotonation requires the presence of an activator in pyruvate decarboxylase from yeast, showing the allosteric regulation of this enzyme to be accomplished by an increase in the C2-H dissociation rate of the enzyme-bound thiamin diphosphate. The data of the thiamin diphosphate analogues and of the mutant enzymes show the N1' atom and the 4'-NH2 group to be essential for the activation of the coenzyme and a conserved glutamate involved in the proton abstraction mechanism of the enzyme-bound thiamin diphosphate.


Assuntos
Piruvato Descarboxilase/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Piruvato Oxidase/metabolismo , Tiamina Pirofosfato/metabolismo , Transcetolase/metabolismo , Regulação Alostérica , Escherichia coli/enzimologia , Cinética , Lactobacillus/enzimologia , Ressonância Magnética Nuclear Biomolecular , Leveduras/enzimologia
8.
J Virol ; 71(12): 9475-81, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9371609

RESUMO

The sequence variability of viral structure polypeptides has been associated with immune escape mechanisms. The V1 region of simian immunodeficiency virus (SIV) is a highly variable region of the SIVmac env gene. Here, we describe the V1 region as a linear neutralizing epitope. V1 region-specific neutralizing antibodies (NAb) were first demonstrated in a rabbit infected with a recombinant vaccinia virus carrying the env gene of human immunodeficiency virus type 2 strain ben (HIV-2ben). Since we detected in this animal V1 region-specific NAb that were able to neutralize not only human immunodeficiency virus type 2 but also SIVmac32H, we investigated whether a similar immune response is evoked in macaques (Macaca mulatta) either infected with SIVmac or immunized with the external glycoprotein (gp130) of the same virus. Distinctly lower NAb titers were found in the SIVmac-infected animals than in the gp130-immunized macaques. Since the NAb titers in both groups were high enough for competition experiments, we used five overlapping peptides encompassing the whole V1 region for a detailed identification of the epitope. In each of the 12 macaques investigated, we detected a high level of NAb reacting with at least one peptide located in the central part of the V1 region. The relatively high degree of divergence, especially within the central part of the V1 region, which characterized the evolution of the retroviral sequences from the original inoculum in the infected macaques suggests the development of escape mutants. Furthermore, 3 of 12 animals developed NAb directed against the amino-terminal end of the V1 region epitope. Sequence analysis, however, revealed relatively low levels of genetic drift and genetic variability within this part of the V1 region. The induction of V1 env-specific NAb not only in gp130-immunized macaques but also in SIVmac-infected animals in combination with the increased genetic variability of this region in vivo indicates a marked biological significance of this epitope for the virus.


Assuntos
Antígenos Virais/imunologia , Epitopos de Linfócito B/imunologia , Produtos do Gene env/imunologia , Vírus da Imunodeficiência Símia/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Linhagem Celular Transformada , Produtos do Gene env/síntese química , Variação Genética , HIV-2/imunologia , Humanos , Macaca mulatta , Dados de Sequência Molecular , Testes de Neutralização , Peptídeos/síntese química , Peptídeos/imunologia , Provírus/genética , Coelhos , Homologia de Sequência de Aminoácidos , Produtos do Gene env do Vírus da Imunodeficiência Humana
9.
Phys Rev C Nucl Phys ; 53(3): 1416-1429, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9971080
10.
J Nurs Adm ; 25(12): 37-43, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8523142

RESUMO

Cost-effective strategies for delivering primary care require the appropriate mix of healthcare providers. The authors define the scope of practice for the advanced practice nurse. Results of a nationwide survey of 26 large healthcare systems and multispecialty group practices are presented. Findings from these practice settings are contrasted with those previously reported in the literature. Implications for the future are discussed.


Assuntos
Prática de Grupo/organização & administração , Enfermeiros Clínicos/estatística & dados numéricos , Profissionais de Enfermagem/estatística & dados numéricos , Assistentes Médicos/estatística & dados numéricos , Análise Custo-Benefício , Emprego , Prática de Grupo/economia , Humanos , Medicina , Qualidade da Assistência à Saúde , Especialização , Especialidades de Enfermagem , Inquéritos e Questionários , Estados Unidos
11.
Acta Neurol Scand ; 92(3): 213-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7484074

RESUMO

INTRODUCTION: In patients with human T-cell lymphotropic virus type 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis (HAM/TSP), we investigated the significance of HTLV-1 specific antibodies in the cerebrospinal fluid (CSF). MATERIAL AND METHODS: The quantities of HTLV-1 specific immunoglobulin G (IgG) in paired CSF and serum were evaluated by a sensitive enzyme immunoassay (EIA). The specificity of antiviral IgG was determined by radioimmunoprecipitation of HTLV-1 antigens. RESULTS: In 17 of 20 HAM/TSP patients, quantitative evaluation by EIA supplied evidence for antiviral IgG synthesis within the CNS. Radioimmunoprecipitation demonstrated IgG antibodies against HTLV-1 envelope and core proteins in all HAM/TSP CSF and sera tested. Regarding the 3 sample pairs indeterminate in EIA for intrathecal synthesis, 2 showed stronger precipitation of HTLV-1 antigens by CSF IgG than by equal amounts of serum IgG. CONCLUSION: Intrathecal antibody synthesis specific for both HTLV-1 core and envelope antigens is common in HAM/TSP, thus providing conclusive evidence for an immune response to HTLV-1 within the CNS.


Assuntos
Especificidade de Anticorpos/imunologia , Anticorpos Anti-HTLV-I/líquido cefalorraquidiano , Antígenos HTLV-I/imunologia , Imunoglobulina G/líquido cefalorraquidiano , Paraparesia Espástica Tropical/imunologia , Proteínas do Core Viral/imunologia , Proteínas do Envelope Viral/imunologia , Barreira Hematoencefálica/imunologia , Brasil , Humanos , Técnicas Imunoenzimáticas , Irã (Geográfico) , Paraparesia Espástica Tropical/diagnóstico , Ensaio de Radioimunoprecipitação
12.
Am J Vet Res ; 55(9): 1250-5, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7802392

RESUMO

Vaccina virus (VV) infection induces specific antibodies and cytotoxic T cells in various animal species. Therefore, helper T cells also should be induced that stimulate the humoral and cellular immune responses. We determined such helper T-cell activity in 2 species after VV infection. Rabbits and rhesus macaques were infected with the Copenhagen strain of VV or with recombinant VV expressing retroviral proteins. Animals of both species developed antibodies and specific proliferative T-cell response. This reactivity could be enhanced by booster infection with VV. The proliferating macaque cells were CD4+ and major histocompatibility complex class II-restricted. These data confirm the broad immunogenicity of VV. Expression of additional polypeptides expressed from a recombinant VV does not lead to altered immune response to VV antigens. However, strength of the helper T-cell response, as well as clinical reactions, differed between macaques and rabbits. Infection with recombinant VV as delivery vectors offers the opportunity for combined vaccination against recombinant proteins and does not diminish cellular and humoral immune responses to VV itself.


Assuntos
Anticorpos Antivirais/sangue , Linfócitos B/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Vaccinia virus/imunologia , Vacínia/imunologia , Animais , Formação de Anticorpos , Antígenos Virais/imunologia , Ensaio de Imunoadsorção Enzimática , Macaca mulatta , Coelhos , Proteínas Recombinantes/imunologia , Fatores de Tempo , Vacínia/sangue , Vacínia/fisiopatologia
13.
Am J Gastroenterol ; 89(2): 254-6, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8304313

RESUMO

Gastrointestinal adenocarcinoma is a disease seen uncommonly in HIV-infected patients. The present case is that of a 25-yr-old black male who was HIV positive and developed right-sided colon adenocarcinoma. This case is an example of the growing number of adenocarcinomas of the gastrointestinal tract being reported in HIV patients. Cases of gastric, pancreatic, and colonic adenocarcinoma in HIV patients are reviewed herein. It seems possible that HIV may play an etiologic role in the increased chance of developing gastrointestinal adenocarcinoma.


Assuntos
Adenocarcinoma/complicações , Neoplasias do Colo/complicações , Infecções por HIV/complicações , Adulto , Humanos , Masculino
16.
Phys Rev Lett ; 71(9): 1328-1331, 1993 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-10055512
17.
Phys Rev C Nucl Phys ; 46(1): 322-329, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9968112
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