151 research outputs found
Thermal Environment Modeling Practices for the Descent Trajectory of Lunar Landers
With the current push to send landers back to the moon, properly modeling the thermal environment for the descent is critical. Descent in this paper is described as: descending from low lunar orbit to touch down on surface. There are several challenges during this period, including: many electronics (such as battery, avionics, transponder, etc) have higher heat loads due to higher power levels, a significant portion of the view factor to space has been blocked out by the moon making heat rejection less efficient, components that normally do not have direct line of sight to the sun may get exposure due to the lander rotating to align for descent, and thruster firing will dump more heat into the lander. All of these factors combine during the most critical phase of a lander mission make it essential that the thermal environment has been properly set up during design and analysis. This paper presents one method of setting up the thermal environment during descent in Thermal Desktop and will also include some tips and tricks
Protocol to Evaluate and Load Rate Existing Bridges
Load tests can be used to verify component and system performance under a known live load and provide an alternative evaluation methodology to analytically computed the load rating of a bridge. Procedures for nondestructive load testing, which involves field observations and measurements of in- service bridges and field testing often can revel additional capacity since analytical bridge rating tend to be fairly conservative. The goal of presented research was to develop a data-driven rating process to assess and rate bridges. This data-driven rating system reduces the subjective judgment of the bridge inspectors through the use of computer models and field load testing, and results in load rating based on field test data. The report discusses procedures to complete a successful field test and acquire the data needed to analyze the results. Developed procedures are illustrated by field testing results for five different types of bridges
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The Influence of Very Low Doses of Cisplatin on Tumor Cell Proliferation In Vitro and on Some Hematological and Enzymatic Parameters of Healthy Rats
Healthy rats had been treated for 2 or 6 weeks with 1.0 mL of 10-8 and 10-16 mg/mL of cisplatin. After 2 weeks of treatment, a significant increase in leukocyte and erythrocyte count and also in hematocrit was observed. Among leukocytes the number of neutrophils and eosinophils significantly increased. Biochemical analyses indicated a decrease in the glycogen content in the liver and kidneys after 2 weeks of treatment with low doses of cisplatin but at the end of the experiment (8th week of experiment) the stores of glycogen increased significantly. Biochemical analyses concerning the activity of some enzymes in the liver revealed a significant increase of peroxidase and acid phosphatase as well as catalase activities after 2 weeks of treatment. However, catalase was induced by a very low concentration of cisplatin, 10-16 mg/mL. After the cessation of cisplatin treatment the activity of enzymes returned to normal values. Human lung carcinoma cell line A549 (ECACC No 86012804) was also studied after treatment with the same doses of cisplatin and inhibition of its growth was observed. The results of these experiments strongly indicated that low doses of cisplatin could be stimulating for healthy cells but cytostatic for tumor cells. Possible mechanisms involved in the biological activity of very low cisplatin concentrations are discussed
Thermal Environment Modeling Practices for the Descent Trajectory of Lunar Landers
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The audio/visual mismatch and the uncanny valley: an investigation using a mismatch in the human realism of facial and vocal aspects of stimuli
Indiana University-Purdue University Indianapolis (IUPUI)Empirical research on the uncanny valley has primarily been concerned with visual elements. The current study is intended to show how manipulating auditory variables of the stimuli affect participant’s ratings. The focus of research is to investigate whether an uncanny valley effect occurs when humans are exposed to stimuli that have an incongruity between auditory and visual aspects. Participants were exposed to sets of stimuli which are both congruent and incongruent in their levels of audio/visual humanness. Explicit measures were used to explore if a mismatch in the human realism of facial and vocal aspects produces an uncanny valley effect and attempt to explain a possible cause of this effect. Results indicate that an uncanny valley effect occurs when humans are exposed to stimuli that have an incongruity between auditory and visual aspects
Reliability analysis of moment redistribution in reinforced concrete beams
Design codes allow a limited amount of moment redistribution in continuous reinforced concrete beams and often make use of lower bound values in the procedure for estimating the moment redistribution factors. Here, based on the concept of demand and capacity rotation, and by means of Monte Carlo simulation, a probabilistic model is derived for the evaluation of moment redistribution factors. Results show that in all considered cases, the evaluated mean and nominal values of moment redistribution factor are greater than the values provided by the ACI code. On the other hand, the 5th percentile value of moment redistribution factor could be lower than those specified by the code. Although the reduction of strength limit state reliability index attributable to uncertainty in moment redistribution factors is not large, it is comparable to the reduction in reliability index resulting from increasing the ratio of live to dead load
A novel curcumin-based vaginal cream Vacurin selectively eliminates apposed human cervical cancer cells
Objective. Human papillomavirus (HPV) infections remain a leading cause of mortality worldwide. In the U.S. strategies via screening and vaccination prevent HPV-associated cervical neoplasms, but consume im- mense healthcare costs. The spice component curcumin has potent anticancer and antiviral properties, which have been difficult to harness as a treatment, due to its poor systemic bioavailability. This project tests the possibility of developing a curcumin-based therapy for cervical cancer.
Methods. Using four HPV(+) cervical cancer cell lines and normal fibroblasts we first tested the selectivity and potency of curcumin in eliminating HPV(+) cells. Subsequently, we developed a curcumin-based cervical cream and tested its efficacy in eliminating apposed HPV(+) cells and also its possible side effects on the vaginal epithelium of healthy mice.
Results. Curcumin selectively eliminates a variety of HPV(+) cervical cancer cells (HeLa, ME-180, SiHa, and SW756), suppresses the transforming antigen E6, dramatically inhibits the expression of the pro-cancer protein epidermal growth factor receptor (EGFR), and concomitantly induces p53. Additionally, Vacurin, a uniform colloidal solution of curcumin in a clinically used amphipathic vaginal cream, eliminates apposed HeLa cells while suppressing the expression of EGFR. In mice, daily intravaginal application of Vacurin for three weeks produced no change in body weight and when the mice were sacrificed, the vaginal tract epithelium showed no Vacurin-evoked adverse effects.
Conclusion. We have developed a curcumin-based vaginal cream, which effectively eradicates HPV(+) cancer cells and does not affect non-cancerous tissue. Our preclinical data support a novel approach for the treatment of cervical HPV infection
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