7,919 research outputs found
Microgravity metal processing: from undercooled liquids to bulk metallic glasses
Bulk metallic glasses (BMGs) are a novel class of metal alloys that are poised for widespread commercialization. Over 30 years of NASA and ESA (as well as other space agency) funding for both ground-based and microgravity experiments has resulted in fundamental science data that have enabled commercial production. This review focuses on the history of microgravity BMG research, which includes experiments on the space shuttle, the ISS, ground-based experiments, commercial fabrication and currently funded efforts
Identification of a novel splice variant of the haloacid dehalogenase: PHOSPHO1
PHOSPHO1, a new member of the haloacid dehalogenase superfamily, has recently been implicated in the mineralization process in both osteoblasts and chondrocytes. In this study we describe the identification of a novel, alternatively spliced PHOSPHO1 transcript (PHOSPHO1-3a). This transcript contains the three exons of the previously published variant, however exon 3 contains a retained, 127bp section of intron 2. This forms an in-frame start site, producing an open reading frame of 879bp and predicting a protein of 292 amino acids. The novel 40 amino acid N-terminal region of PHOSPHO1-3a contains a relatively strong secretory signal, however all three domains of the HAD superfamily are retained in exon 3. The expression of this splice variant was confirmed in both human and mouse osteoblast-like cells and also in the chondrogenic ATDC5 cell line. The data within this study indicate a possible function relating to chondrocyte differentiation/mineralization as with the previously published variant
The Metabolism and Transplacental Transfer of Oseltamivir in the Ex Vivo Human Model
Oseltamivir phosphate is extensively metabolized in the ex vivo
human placenta model, and the transplacental passage of the metabolite oseltamivir
carboxylate is incomplete. Objective. To evaluate the metabolism and transplacental transfer of oseltamivir (Tamiflu) in the ex vivo human placental model.
Study Design. Perfusion studies were performed in six placentas from term, uncomplicated deliveries. Concentrations of oseltamivir phosphate (OP) that were 5-6 fold, 20–30 fold, and 600–800 fold above the therapeutic peak were tested, as neither OP nor its active metabolite, oseltamivir carboxylate (OC),
could be detected at near-therapeutic concentrations. The transplacental transfer and accumulation of OC were
assessed using the 14C antipyrine reference method.
Results. OP was extensively metabolized to OC. In the 4 placentas with the highest concentration of OP, OC had a mean clearance index of 0.13 ± 0.08, suggesting that transplacental passage occurs at a relatively low rate. Measurable fetal accumulation occurred in the two placentas with the highest initial concentrations.
Conclusions. Oseltamivir phosphate was extensively metabolized in the ex vivo model. Transplacental transfer of the metabolite was incomplete and accumulation was minimal
Design study of an integrated aerobraking orbital transfer vehicle
An aerobraking orbital transfer vehicle (AOTV) concept, which has an aerobrake structure that is integrated with the propulsion stage, is discussed. The concept vehicle is to be assembled in space and is space-based. The advantages of aeroassist over an all propulsive vehicle are discussed and it is shown that the vehicle considered is very competitive with inflatable and deployable concepts from mass and performance aspects. The aerobrake geometry is an ellipsoidally blunted, raked-off, elliptical wide-angle cone with a toroidal skirt. Propellant tanks, engines, and subsystems are integrated into a closed, isogrid aerobrake structure which provides rigidity. The vehicle has two side-firing, gimbaled RL-10 type engines and carries 38,000 kg of useable propellant. The trajectory during aerobraking is determined from an adaptive guidance logic, and the heating is determined from engineering correlations as well as 3-D Navier-Stokes solutions. The AOTV is capable of placing 13,500 kg payload into geosynchronous Earth orbit (GEO) or carrying a LEO-GEO-LEO round-trip payload of 7100 kg. A two-stage version considered for lunar missions results in a lunar surface delivery capability of 18,000 kg or a round-trip capability of 6800 kg with 3860 kg delivery-only capability
Springs of Florida
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which documented the major and important springs in the state (Ferguson et al., 1947).
This publication was revised in 1977, with many previously undocumented springs and
many new water-quality analyses being added (Rosenau et al., 1977). The Florida
Geological Survey's report on first magnitude springs (Scott et al., 2002) was the initial step
in once again updating and revising the Springs of Florida bulletin. The new bulletin
includes the spring descriptions and water-quality analyses from Scott et al. (2002). Nearly
300 springs were described in 1977. As of 2004, more than 700 springs have been recognized
in the state and more are reported each year. To date, 33 first magnitude springs (with a
flow greater than 100 cubic feet per second or approximately 64.6 million gallons of water
per day) have been recognized in Florida, more than any other state or country (Rosenau et
al., 1977). Our springs are a unique and invaluable natural resource. A comprehensive
understanding of the spring systems will provide the basis for their protection and wise use.
(Document pdf contains 677 pages
Percutaneous Thrombin Injection for Treatment of a Splenic Artery Aneurysm
AbstractSplenic artery aneurysms are an uncommon entity and are usually asymptomatic when diagnosed. Treatment is based on size, with aneurysms greater than 2 cm usually undergoing surgical repair. We present a case in which percutaneous thrombin injection was used for treatment of a splenic artery aneurysm
Associations between social support, psychological well-being, decision making, empowerment, infant and young child feeding, and nutritional status in Ugandan children ages 0 to 24months
Maternal capabilitiesqualities of mothers that enable them to leverage skills and resources into child healthhold potential influence over mother\u27s adoption of child caring practices, including infant and young child feeding. We developed a survey (n=195) that assessed the associations of 4 dimensions of maternal capabilities (social support, psychological health, decision making, and empowerment) with mothers\u27 infant and young child feeding practices and children\u27s nutritional status in Uganda. Maternal responses were converted to categorical subscales and an overall index. Scale reliability coefficients were moderate to strong ( range=0.49 to 0.80). Mothers with higher social support scores were more likely to feed children according to the minimum meal frequency (odds ratio [OR] [95% confidence interval (CI)]=1.38 [1.10, 1.73]), dietary diversity (OR [95% CI]=1.56 [1.15, 2.11]), iron rich foods, (OR [95% CI]=1.47 [1.14, 1.89]), and minimally acceptable diet (OR [95% CI]=1.55 [1.10, 2.21]) indicators. Empowerment was associated with a greater likelihood of feeding a minimally diverse and acceptable diet. The maternal capabilities index was significantly associated with feeding the minimum number of times per day (OR [95% CI]=1.29 [1.03, 1.63]), dietary diversity (OR [95% CI]=1.44 [1.06, 1.94]), and minimally acceptable diet (OR [95% CI]=1.43 [1.01, 2.01]). Mothers with higher psychological satisfaction were more likely to have a stunted child (OR [95% CI]=1.31 [1.06, 1.63]). No other associations between the capabilities scales and child growth were significant. Strengthening social support for mothers and expanding overall maternal capabilities hold potential for addressing important underlying determinants of child feeding in the Ugandan context
Resolution of Nodular Fasciitis in the Upper Arm
AbstractNodular fasciitis is a benign fibroblastic lesion that was historically misdiagnosed as a malignant neoplasm. Patients present with pain and swelling of relatively brief duration. The clinical presentation is suggestive of an aggressive lesion, usually occurring in muscle fascia. Histologic features can cause it to be mistaken for sarcoma. After the diagnosis is established histologically, observation is the suggested treatment. We present the case of a patient who had a large soft-tissue tumor in the upper arm with a clinical picture indicative of sarcoma, which ultimately was diagnosed as nodular fasciitis. The patient was treated with anti-inflammatory agents and observation. Within 7 months, the mass almost completely resolved, as documented by magnetic resonance imaging
Biomimetic strategies for fracture repair: engineering the cell microenvironment for directed tissue formation
Complications resulting from impaired fracture healing have major clinical implications on fracture management strategies. Novel concepts taken from developmental biology have driven research strategies towards the elaboration of regenerative approaches that can truly harness the complex cellular events involved in tissue formation and repair. Advances in polymer technology and a better understanding of naturally derived scaffolds have given rise to novel biomaterials with an increasing ability to recapitulate native tissue environments. This coupled with advances in the understanding of stem cell biology and technology has opened new avenues for regenerative strategies with true clinical translatability. These advances have provided the impetus to develop alternative approaches to enhance the fracture repair process. We provide an update on these advances, with a focus on the development of novel biomimetic approaches for bone regeneration and their translational potential
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