500 research outputs found
A trajectory generation and system characterization model for cislunar low-thrust spacecraft. Volume 2: Technical manual
The documentation of the Trajectory Generation and System Characterization Model for the Cislunar Low-Thrust Spacecraft is presented in Technical and User's Manuals. The system characteristics and trajectories of low thrust nuclear electric propulsion spacecraft can be generated through the use of multiple system technology models coupled with a high fidelity trajectory generation routine. The Earth to Moon trajectories utilize near Earth orbital plane alignment, midcourse control dependent upon the spacecraft's Jacobian constant, and capture to target orbit utilizing velocity matching algorithms. The trajectory generation is performed in a perturbed two-body equinoctial formulation and the restricted three-body formulation. A single control is determined by the user for the interactive midcourse portion of the trajectory. The full spacecraft system characteristics and trajectory are provided as output
A prospective 7-year survey on central venous catheter-related complications at a single pediatric hospital
A Meta-Analysis on the Effects of Hydroxychloroquine on COVID-19.
Introduction Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread throughout the world with a large medical and economic impact. On March 12, 2020, the World Health Organization (WHO) classified SARS-CoV-2 as a pandemic. As a result of this worldwide public health crisis, politicians, elected officials, and healthcare professionals emergently began trialing hydroxychloroquine (HCQ) in efforts to treat and prevent the transmission of the virus. This meta-analysis was performed to assess the effects of HCQ on patients with COVID-19. Methods This meta-analysis adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRIMA) guidelines. Selected articles published between December 2019 and July 2020 were found utilizing the following search engines: PubMed, Google Scholar, Cochrane Library, DisasterLit, Clinicaltrials.gov, Medrxiv, and Embase. Two independent physician reviewers screened eligible articles that met the inclusion and exclusion criteria of the analysis. The outcome measures analyzed were mortality rate, rate of disease progression/improvement, rate of disease severity, and adverse effects of treatment. Six out of 14 studies that met the study\u27s eligibility criteria were selected and further analyzed, with a total of 381 participants (n= 381). Conclusion From the studies analyzed, it was found that groups treated with HCQ had an overall mortality rate that was 2.5 times greater than that of the control group. HCQ treated patients had higher rates of adverse clinical outcomes and side effects compared with the control populations. Lastly, there was a 1.2 times higher rate of improvement in the group of HCQ treated patients with mild to moderate symptoms as compared to the control group
Combined liver kidney transplantation for primary hyperoxaluria type 1: Will there still be a future? Current transplantation strategies and monocentric experience
Mapping Interactions Between the Amino-Terminal Region of Secretin and its Receptor using Disulfide-Trapping
Recombinant human erythropoietin in the treatment of chemotherapy-induced anemia and prevention of transfusion requirement associated with solid tumors: A randomized, controlled study
Background: Anemia is a common side effect of anticancer chemotherapy. Blood transfusion, previously the only available treatment for chemotherapy-induced anemia, may result insome clinical or subclinical adverse effects in the recipients. Recombinant human erythropoietin (rhEPO) provides a new treatment modality for chemotherapy-induced anemia. Patients and methods: To evaluate the effect of rhEPO onthe need for blood transfusions and on hemoglobin (Hb)concentrations, 227 patients with solid tumors and chemotherapy-induced anemia were enrolled in a randomized, controlled, clinical trial. Of 189 patients evaluable for efficacy, 101 received 5000 IU rhEPO daily s.c, while 88 patients received no treatment during the 12-week controlled phase of the study. Results: The results demonstrate a statistically significant reduction in the need for blood transfusions (28% vs. 42%, P = 0.028) and in the mean volume of packed red blood cells transfused (152 ml vs. 190 ml, p = 0.044) in patients treated with rhEPO compared to untreated controls. This effect was even more pronounced in patients receiving platinum-based chemotherapy (26% vs. 45%, % 0.038). During the controlled treatment phase, the median Hb values increased in the rhEPO patients while remaining unchanged in the control group. The response was seen in all tumor types. Conclusions: RhEPO administration at a dose of 5000 IU daily s.c. increases hemoglobin levels and reduces transfusionrequirements in chemotherapy-induced anemia, especially during platinum-based chemotherap
Tag relatedness in image folksonomies
Folksonomies - networks of users, resources, and tags allow users to easily retrieve, organize and browse web contents. However, their advantages are still limited mainly due to the noisiness of user provided tags. To overcome this issue, we propose an approach for characterizing related tags in folksonomies: we use tag co-occurrence statistics and Laplacian score based feature selection in order to create empirical co-occurrence probability distribution for each tag; then we identify related tags on the basis of the dissimilarity between their distributions. For this purpose, we introduce variant of the Jensen-Shannon Divergence, which is more robust to statistical noise. We experimentally evaluate our approach using WordNet and compare it to a common tag-relatedness approach based on the cosine similarity. The results show the effectiveness of our approach and its advantage over the competing method
Doping and phase segregation in Mn2+- and Co2+-doped lead halide perovskites from Cs-133 and H-1 NMR relaxation enhancement
Lead halide perovskites belong to a broad class of compounds with appealing optoelectronic and photovoltaic properties. Doping with transition metal ions such as Mn2+ and Co2+ has recently been reported to substantially enhance luminescence and stability of these materials. However, so far atomic-level evidence for incorporation of the dopants into perovskite phases has been missing. Here, we introduce a general and straightforward method for confirming the substitutional doping of bulk perovskite phases with paramagnetic dopants. Using Cs-133 and H-1 solid-state MAS NMR relaxation measurements we provide for the first time direct evidence that, consistent with current understanding, Mn2+ is incorporated into the perovskite lattice of CsPbCl3 and CsPbBr3 and does not form clusters. We also show that, contrary to current conviction, Co2+ is not incorporated into the perovskite lattice of MAPbI(3)
Anti-CD3 antibody treatment reduces scar formation in a rat model of myocardial infarction
Introduction: Antibody treatment with anti-thymocyte globulin (ATG) has been shown
to be cardioprotective. We aimed to evaluate which single anti-T-cell epitope antibody alters
chemokine expression at a level similar to ATG and identified CD3, which is a T-cell co-receptor
mediating T-cell activation. Based on these results, the effects of anti-CD3 antibody treatment on
angiogenesis and cardioprotection were tested in vitro and in vivo. Methods: Concentrations of
IL-8 and MCP-1 in supernatants of human peripheral blood mononuclear cell (PBMC) cultures
following distinct antibody treatments were evaluated by Enzyme-linked Immunosorbent Assay
(ELISA). In vivo, anti-CD3 antibodies or vehicle were injected intravenously in rats subjected to acute
myocardial infarction (AMI). Chemotaxis and angiogenesis were evaluated using tube and migration
assays. Intracellular pathways were assessed using Western blot. Extracellular vesicles (EVs) were
quantitatively evaluated using fluorescence-activated cell scanning, exoELISA, and nanoparticle
tracking analysis. Also, microRNA profiles were determined by next-generation sequencing. Results:
Only PBMC stimulation with anti-CD3 antibody led to IL-8 and MCP-1 changes in secretion, similar
to ATG. In a rat model of AMI, systemic treatment with an anti-CD3 antibody markedly reduced
infarct scar size (27.8% (Inter-quartile range; IQR 16.2–34.9) vs. 12.6% (IQR 8.3–27.2); p < 0.01). The
secretomes of anti-CD3 treated PBMC neither induced cardioprotective pathways in cardiomyocytes
nor pro-angiogenic mechanisms in human umbilical vein endothelial cell (HUVECs) in vitro. While
EVs quantities remained unchanged, PBMC incubation with an anti-CD3 antibody led to alterations
in EVs miRNA expression. Conclusion: Treatment with an anti-CD3 antibody led to decreased scar size in a rat model of AMI. Whereas cardioprotective and pro-angiogenetic pathways were unaltered
by anti-CD3 treatment, qualitative changes in the EVs miRNA expression could be observed, which
might be causal for the observed cardioprotective phenotype. We provide evidence that EVs are
a potential cardioprotective treatment target. Our findings will also provide the basis for a more
detailed analysis of putatively relevant miRNA candidates
Métodos y progreso de la conservación de los recursos genéticos de los olmos en Europa
The progress made in the conservation of European elm genetic resources since the 1st International Elm Conference is reviewed, and the complementarity of in situ and ex situ methods is discussed. The financial support of the European Union to RESGEN project CT96-78 has permitted to co-ordinate and rationalize the ex situ conservation of elms. The project, which involved 17 partner institutes in nine west European countries, aimed at a better evaluation, conservation and utilisation of the existing collections of native elm clones. Main achievements are: establishing a common database of about 2,000 clones; characterizing over 500 clones through RAPDs and chloroplast DNA PCR-RFLPs molecular markers; completing and rationalizing the existing collections; establishing a long-term core collection of 850 clones; cryo-preserving a subset of 444 clones; and identifying clones of interest for breeding and prudent use in the reconstruction of countryside hedges. The «Noble Hardwoods» network of the pan-European programme EUFORGEN groups members representative of 31 countries, and promotes the dynamic conservation of the genetic resources of several genera of broadleaf forest trees, including Ulmus spp. Strategies for the conservation of the adaptive potential of elm resources were defined and will be disseminated among foresters and conservationists through «Guidelines» leaflets. Some countries have already started implementing conservation measures for U. laevis, associating in situ preservation and the establishment of seed orchards. Others are undertaking inventories, or acquiring genetic knowledge on target populations.Se discute el progreso realizado en la conservación de los olmos europeos desde la primera conferencia Internacional del Olmo y los métodos complementarios de conservación in situ y ex situ. El apoyo financiero de la Unión Europea al proyecto RESGEN CT96-78 ha permitido coordinar y racionalizar la conservación ex situ de los olmos. El proyecto, en el cual están involucrados 17 instituciones participantes en nueve países de Europa Occidental, tiene por objetivo una mejor evaluación, conservación y utilización de las colecciones actualmente existentes de clones nativos de olmo. Los principales logros son: el establecimiento de una base de datos común de aproximadamente 2.000 clones; la caracterización de más de 500 clones usando RAPD y marcadores moleculares PCR-RFLP de ADN cloroplástico; la finalización y racionalización de las colecciones existentes; el establecimiento a largo plazo de una colección central con 850 clones; la criopreservación de un conjunto de 444 clones; y la identificación de clones de interés para la mejora y para su uso en la restauración de setos en campo. La red «Noble Hardwoods» del programa pan-europeo EUFORGEN agrupa a miembros representantes de 31 países, y promueve la conservación dinámica de los recursos genéticos de varios géneros de árboles planifolios, incluido Ulmus spp.. Las estrategias para la conservación del potencial adaptativo de los recursos de los olmos se definieron y se dieron a conocer entre forestales y conservacionistas a través de folletos guía. Algunos países han comenzado ya a implementar medidas de conservación para U. laevis mediante el uso de la preservación in situ y el establecimiento de huertos semilleros. Otros están elaborando inventarios, o adquiriendo información genética de poblaciones de interés
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