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1.
Anaesthesia ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110992
2.
Nano Lett ; 24(32): 9916-9922, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39087720

RESUMO

The performance of metal and polymer foams used in inertial confinement fusion (ICF), inertial fusion energy (IFE), and high-energy-density (HED) experiments is currently limited by our understanding of their nanostructure and its variation in bulk material. We utilized an X-ray-free electron laser (XFEL) together with lensless X-ray imaging techniques to probe the 3D morphology of copper foams at nanoscale resolution (28 nm). The observed morphology of the thin shells is more varied than expected from previous characterizations, with a large number of them distorted, merged, or open, and a targeted mass density 14% less than calculated. This nanoscale information can be used to directly inform and improve foam modeling and fabrication methods to create a tailored material response for HED experiments.

3.
Opt Express ; 31(18): 29411-29426, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710742

RESUMO

The stratospheric wind field provides significant information on the dynamics, constituent, and energy transport in the Earth's atmosphere. The measurement of the atmospheric wind field on a global basis at these heights is still lacking because few wind imaging interferometers have been developed that can measure wind in this region. In this paper, we describe an advanced compact static wind imaging Michelson interferometer (SWIMI) developed to measure the stratospheric wind field using near-infrared airglow emissions. The instrument contains a field widened and thermal compensated interferometer with a segmented reflective mirror in one arm, which replace the moving mirror in a conventional Michelson interferometer, to provide interference phase steps. The field widened, achromatic, temperature compensated scheme has been designed and manufactured. The characterization, calibration, inversion software, and test of the instrument have been completed. The capacity of two-dimensional wind, temperature, and ozone measurement of the instrument has been verified in the lab experiment and model simulation. What we believe to be the novel principle, modeling, design, and experiment demonstrated in this paper will offer a significant reference to the static, simultaneous and real-time detection and inversion of the global wind field, temperature, and ozone.

4.
Front Robot AI ; 10: 1099297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37476205

RESUMO

Based on the NASA in-Space Assembled Telescope (iSAT) study (Bulletin of the American Astronomical Society, 2019, 51, 50) which details the design and requirements for a 20-m parabolic in-space telescope, NASA Langley Research Center (LaRC) has been developing structural and robotic solutions to address the needs of building larger in-space assets. One of the structural methods studied involves stackable and collapsible modular solutions to address launch vehicle volume constraints. This solution uses a packing method that stacks struts in a dixie-cup like manner and a chemical composite bonding technique that reduces weight of the structure, adds strength, and offers the ability to de-bond the components for structural modifications. We present in this paper work towards a soft material robot end-effector, capable of suppling the manipulability, pressure, and temperature requirements for the bonding/de-bonding of these conical structural components. This work is done to investigate the feasibility of a hybrid soft robotic end-effector actuated by Twisted and Coiled Artificial Muscles (TCAMs) for in-space assembly tasks. TCAMs are a class of actuator which have garnered significant recent research interest due to their allowance for high force to weight ratio when compared to other popular methods of actuation within the field of soft robotics, and a muscle-tendon actuation design using TCAMs leads to a compact and lightweight system with controllable and tunable behavior. In addition to the muscle-tendon design, this paper also details the early investigation of an induction system for adhesive bonding/de-bonding and the sensors used for benchtop design and testing. Additionally, we discuss the viability of Robotic Operating System 2 (ROS2) and Gazebo modeling environments for soft robotics as they pertain to larger simulation efforts at LaRC. We show real world test results against simulation results for a method which divides the soft, continuous material of the end-effector into discrete links connected by spring-like joints.

5.
Ecotoxicology ; 31(10): 1565-1582, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36462130

RESUMO

We tested lethal and sublethal effects of five commonly applied herbicides on the agrobiont wolf spider Pardosa milvina. Pardosa were collected from two agricultural fields; one kept under continuous crop rotation and sprayed for over twenty years, the other had no pesticide application for the last twelve years. Male and female Pardosa from each site were exposed to one of seven herbicide treatments (atrazine, glyphosate, mesotrione, S-metolachlor, rimsulfuron, a combination of all five herbicides, or a distilled water control; N = 1201) and maintained for 52 days on the treated soil substrate. We recorded mortality, prey capture behavior, weight change, courtship behavior, and egg sac production across treatments. Mesotrione and the five-herbicide combination showed significantly higher mortality than control substrates while atrazine, glyphosate and S-metolachlor showed significantly higher survival than the control. Both male spiders and spiders collected from the conventional field had reduced survival under some herbicide treatments. Prey capture behavior varied significantly by herbicide treatment, sex, and site. We observed significant weight change differences in males and differences in egg sac production in females, with, compared to the control, significant male weight loss in the rimsulfuron treatment collected from the no herbicide field, and a decrease in egg sac production in rimsulfuron and S-metolachlor treatments among females collected from the no herbicide field. Our results show some herbicides may have modest but significant fitness benefits (atrazine, glyphosate, and S-metolachlor) while others strongly increase the mortality of a generalist predator (mesotrione and the combination herbicide treatment).


Assuntos
Herbicidas , Feminino , Masculino , Animais , Herbicidas/toxicidade
6.
Appl Opt ; 61(22): 6627-6641, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255889

RESUMO

The first, to our knowledge, successful laboratory implementation of an approach to image winds using simultaneous (as opposed to sequential) fringe imaging of suitable isolated spectral emission lines is described. Achieving this in practice has been a long-standing goal for wind imaging using airglow. It avoids the aliasing effects of source irradiance variations that are possible with sequential fringe sampling techniques. Simultaneous fringe imaging is accomplished using a field-widened Michelson interferometer by depositing phase steps on four quadrants of one of the mirrors and designing an optical system so that four images of the scene of interest, each at a different phase, are simultaneously produced. In this paper, the instrument characteristics, its characterization, and the analysis algorithms necessary for use of the technique for this type of interferometer are described for the first time, to the best of our knowledge. The large throughput associated with field-widened Michelson interferometers is sufficient for the spatial resolutions and temporal cadences necessary for ground based imaging of gravity waves in wind and irradiance to be achieved. The practical demonstration of this technique also validates its use for proposed monolithic satellite instruments for wind measurements using airglow on the Earth and Mars.

7.
J Hand Surg Am ; 47(3): 290.e1-290.e11, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34266682

RESUMO

PURPOSE: To evaluate the clinical and radiographic outcomes of patients who underwent semiconstrained distal radioulnar joint arthroplasty. METHODS: A retrospective analysis was performed on a series of patients who underwent distal radioulnar joint arthroplasty with more than a 23-month follow up. The quantitative outcome variables included the visual analog scale for pain; Disability of the Arm, Shoulder, and Hand (DASH) score; Patient-Rated Wrist Evaluation (PRWE); and Mayo wrist score. The range of motion, grip strength, torque, and lifting capacity were measured at final follow up and compared with that of the nonsurgical extremity. Complications related to the prosthesis were assessed. RESULTS: Twenty-one patients (mean age 57 years) were assessed at an average 41-month follow up (23-73 months). Fifteen underwent prior hand, wrist, or elbow procedures. Four patients required 5 reoperations. The postoperative median visual analog scale pain score was 0.6 at rest and 2.1 with activity. The median postoperative DASH score was 26.7, PRWE 41, and Mayo wrist score was 65. Upon comparing the supination torque of the operative and intact sides, the operative side was found to average 87% of the intact side on a work simulator and 77% on the simulator's D-ring. Eight of 20 patients had lysis around the collar of the ulnar component (40%), as detected using radiography. Three of 21 (14%) radial plates were malpositioned, with 2 resulting in a fracture. The overall complication rate was 29%. CONCLUSIONS: Distal radioulnar joint arthroplasty using the Scheker prosthesis demonstrated good patient pain scores and the restoration of supination strength. The collar lysis resulted in weaker supination and grip strength. Still, the patients experienced mild levels of pain and moderate disability. A moderate complication rate persisted, as reported by other authors. Accurate radial component placement is important. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Artroplastia de Substituição , Prótese Articular , Artroplastia de Substituição/métodos , Humanos , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/cirurgia
9.
J Trauma Acute Care Surg ; 91(3): 514-520, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33990533

RESUMO

BACKGROUND: Uncontrolled truncal hemorrhage remains the most common cause of potentially preventable death after injury. The notion of earlier hemorrhage control and blood product resuscitation is therefore attractive. Some systems have successfully implemented prehospital advanced resuscitative care (ARC) teams. Early identification of patients is key and is reliant on rapid decision making and communication. The purpose of this simulation study was to explore the feasibility of early identification of patients who might benefit from ARC in a typical US setting. METHODS: We conducted a prospective observational/simulation study at a level I trauma center and two associated emergency medical service (EMS) agencies over a 9-month period. The participating EMS agencies were asked to identify actual patients who might benefit from the activation of a hypothetical trauma center-based ARC team. This decision was then communicated in real time to the study team. RESULTS: Sixty-three patients were determined to require activation. The number of activations per month ranged from 2 to 15. The highest incidence of calls occurred between 4 pm to midnight. Of the 63 patients, 33 were transported to the trauma center. The most common presentation was with penetrating trauma. The median age was 27 years (interquartile range, 24-45 years), 75% were male, and the median Injury Severity Score was 11 (interquartile range, 7-20). Based on injury patterns, treatment received, and outcomes, it was determined that 6 (18%) of 33 patients might have benefited from ARC. Three of the patients died en-route to or soon after arrival at the trauma center. CONCLUSION: The prehospital identification of patients who might benefit from ARC is possible but faces challenges. Identifying strategies to adapt existing processes may allow better utilization of the existing infrastructure and should be a focus of future efforts. LEVEL OF EVIDENCE: Prognostic/Epidemiologic, level III.


Assuntos
Serviços Médicos de Emergência/organização & administração , Hemorragia/mortalidade , Ressuscitação/métodos , Ferimentos e Lesões/mortalidade , Adulto , Alabama/epidemiologia , Serviços Médicos de Emergência/métodos , Feminino , Hemorragia/etiologia , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades/estatística & dados numéricos , Equipe de Assistência ao Paciente/organização & administração , Estudos Prospectivos , Centros de Traumatologia , Ferimentos e Lesões/complicações , Ferimentos e Lesões/terapia , Adulto Jovem
10.
Transfusion ; 61(6): 1980-1986, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33899963

RESUMO

BACKGROUND: Donor-specific antibodies (DSA) to HLA have been associated with graft loss in hematopoietic progenitor cell (HPC) transplantation. Limited data associate therapeutic plasma exchange (TPE) with desensitization and successful engraftment. We report an attempt of desensitization and observed overshooting of DSA during transplantation. CASE REPORT AND RESULTS: A 27-year-old female with cutaneous T cell lymphoma was scheduled for HPC transplantation from her HLA-haploidentical half-sister, who carried the HLA-DRB1*13:03:01 allele. The patient had the corresponding DSA. Lacking an alternative donor option at the time, we attempted a desensitization approach by immunosuppression with tacrolimus and mycophenolate mofetil (MMF). Unexpectedly, DSA increased from a mean fluorescence intensity (MFI) of 1835 on day -63 to 9008 on day -7. The MFI increased further during 3 TPE procedures and intravenous immunoglobulin (IVIG) until day -1. After transplantation, the DSA remained elevated despite 2 more TPE/IVIG procedures and graft-versus-host disease prophylaxis with high-dose cyclophosphamide, sirolimus, and MMF. Flow cytometric crossmatch, initially negative, turned positive after transplantation. Primary graft failure occurred and was attributed to antibody-mediated rejection. A second transplantation from a 7/8 HLA-matched unrelated donor, not carrying DRB1*13:03 allele, resulted in successful engraftment. CONCLUSION: Unexpected and rapid increases of a DSA can occur despite the use of current desensitization approaches. This is problematic when conditioning has already started, as such increases are unlikely to be overcome by TPE or other interventions for desensitization. Overshoot of DSA in HPC transplantation has rarely been reported. Its cause remains unclear and can include underlying disease, immunotherapy, chemotherapy, or TPE.


Assuntos
Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas , Linfoma Cutâneo de Células T/terapia , Troca Plasmática , Adulto , Anticorpos/sangue , Anticorpos/imunologia , Feminino , Antígenos HLA/sangue , Humanos , Terapia de Imunossupressão , Linfoma Cutâneo de Células T/sangue , Linfoma Cutâneo de Células T/imunologia , Doadores de Tecidos
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