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91.
This paper addresses a computational procedure to assess the lethality of kinetic energy projectile warheads against tactical ballistic missile payloads with an innovative and rational damage metric. The individual lethality of different projectile geometries impacting at hypervelocity at different configurations is estimated via a numerical damage index computed from hydrocode simulations. The highest count of possible impacts to the payload is achieved by optimizing the warhead’s configuration and time of detonation, a priori knowledge of the target’s location and speed. The total damage to the payload characterizes the warhead’s lethality for the particular engagement conditions. An example shows the application of the process and potential advantages. 相似文献
92.
93.
Lucio Díaz-Flores Ricardo Gutirrez Miriam Gonzlez-Gmez Maria Pino García Lucio Díaz-Flores Jr. Jos Luís Carrasco Pablo Martín-Vasallo 《International journal of molecular sciences》2021,22(7)
Several origins have been proposed for cancer-associated fibroblasts (CAFs), including resident CD34+ stromal cells/telocytes (CD34+SCs/TCs). The characteristics and arrangement of mammary CD34+SCs/TCs are well known and invasive lobular carcinoma of the breast (ILC) is one of the few malignant epithelial tumours with stromal cells that can express CD34 or αSMA, which could facilitate tracking these cells. Our objective is to assess whether tissue-resident CD34+SCs/TCs participate in the origin of CAFs in ILCs. For this purpose, using conventional and immunohistochemical procedures, we studied stromal cells in ILCs (n:42) and in normal breasts (n:6, also using electron microscopy). The results showed (a) the presence of anti-CD34+ or anti-αSMA+ stromal cells in varying proportion (from very rare in one of the markers to balanced) around nests/strands of neoplastic cells, (b) a similar arrangement and location of stromal cells in ILC to CD34+SCs/TCs in the normal breast, (c) both types of stromal cells coinciding around the same nest of neoplastic cells and (d) the coexpression of CD34 and αSMA in stromal cells in ILC. In conclusion, our findings support the hypothesis that resident CD34+SCs/TCs participate as an important source of CAFs in ILC. Further studies are required in this regard in other tumours. 相似文献
94.
M.D. Hernández M.C. Romero-Ternero F. Sivianes A. Carrasco 《Applied Artificial Intelligence》2019,33(2):124-136
This paper describes a multiagent architecture integrated system designed to supervise infrastructures in solar farms. The system enables monitoring the environment by means of sensor networks that are in charge of collecting data. It is designed using a hybrid model composed of an inference engine and an ontology. The former makes the system intelligent, while the latter structures knowledge. We have also developed a tool to configure and use the multiagent system in a simple and intuitive way. 相似文献
95.
S González Gallardo S Mendoza Elvira J Pujols Romeu I Badiola Saiz A Ciprián Carrasco E Hernández Baumgarten 《Canadian Metallurgical Quarterly》1997,28(3):349-354
Four strains of Aujeszky's Disease virus (ADV) were included in this study; three Mexican field isolates (215,145 and C-8) in conjunction with the Shope reference strain of ADV, which has known pathogenic characteristics. All four strains were included in each treatment, which consisted of heat treatment, trypsin treatment and passed ten times on chicken embryo fibroblasts. Both virus titer and plaque size were determined on the first and tenth passage and on treated and untreated strains. On each of the treatments, the plaque size had significant differences (p = 0.001) which had relation to the two factors studied, namely strain and passage level. There was no significant variation related to the type of treatment between strains. With the strains under study, the authors also made rabbit pathogenicity tests, and it was found that on passage one, the strains caused clear nervous symptoms and death, while on the tenth passage level, the Mexican strains produced slight pruritus, few nervous symptoms and allowed the rabbits to survive. The mouse test revealed an increased median death time after the treatments, as well as a large increase in standard deviations. These data are interpreted as an increased heterogeneity of the strains in all of the treatments to the strains of viruses. 相似文献
96.
F Pérez T Lafayette JL Santos M Calivillán E Carrasco 《Canadian Metallurgical Quarterly》1997,125(11):1329-1334
BACKGROUND: Lipoprotein lipase plays a crucial role in plasma lipoprotein metabolism. Several lipoprotein lipase gene polymorphisms have been found associated with lipid levels, premature atherosclerosis and cardiovascular disease. AIM: To investigate, in the Chilean population, the genotype distribution of lipoprotein lipase polymorphisms and its possible association with lipid levels and obesity. PATIENTS AND METHODS: Hind III and Pvu II polymorphism was determined in 45 non-insulin-dependent diabetic patients and in 52 non diabetic controls from Santiago, Chile. RESULTS: Hind III (+/+) polymorphism had a higher frequency in diabetics as compared to controls (0.6 and 0.29 respectively, p = 0.009). The frequency of heterozygous distribution was higher in non diabetic subjects. Controls and diabetics had comparable gene frequencies for the Pvu II genotype distribution. Analyzing the impact of these polymorphisms on plasma lipid levels, Hind III (+/+) genotype was associated with high levels of total cholesterol and triglycerides in both groups. The heterozygote (+/-) or homozygote (-/-) state for Hind III was effectively associated with high levels of HDL cholesterol levels, as compared to the (+/+) genotype. There was no relationship between these genotypes and body mass index and waist to hip ratio. CONCLUSIONS: An association between genetic variation at the lipoprotein lipase locus with high levels of triglycerides and total cholesterol was confirmed. However, no association of these genetic markers with anthropometric measurements was found. 相似文献
97.
2.45 GHz planar inverted-F antenna (PIFA) designs mounted on a 100 mm square ground plane are examined with regard to the feed-element shape influence on the input bandwidth (BW). While the traditional wire-fed PIFA has a BW from about 4 to 12%, the novel PIFAs with diverse feed plates (triangular, bi-triangular, rectangular, rounded-rectangular and U-strip) are designs capable of a much broader BW, between 18 and 25% for some configurations. 相似文献
98.
The mechanisms that regulate the selective infiltration of eosinophils in certain allergic diseases are still poorly understood. The CC chemokine eotaxin is a potent chemoattractant, highly specific for eosinophils. Recent studies have implicated that eotaxin plays an important role in the recruitment of eosinophils in different inflammation processes. A number of other chemokines, cytokines, and chemoattractants also have chemotactic activities for eosinophils and some of them present high selectivity for eosinophils. To further study the role of eotaxin in inflammation, we generated mutant mice with the eotaxin gene disrupted and replaced by the Escherichia coli beta-galactosidase gene. These mice developed normally and had no histologic or hematopoietic abnormalities. Furthermore, our studies showed that the lack of eotaxin did not affect the recruitment of eosinophils in the inflammation models induced by Sephadex beads and thioglycollate, as well as in an experimental lung eosinophilia model induced by ovalbumin aerosol challenge, even at the onset of the inflammatory response. The replacement of the eotaxin gene by the beta-galactosidase gene provided a useful marker to monitor the activity of the eotaxin promoter under normal conditions and after antigen challenges. Immunohistochemical staining suggested that endothelial cells were the major sources of eotaxin expression. 相似文献
99.
To reexamine the role of covert attention in visual search, the authors directly manipulated attention by peripherally cueing the target location and analyzed its effects on the set-size and the eccentricity effects. Observers participated in feature and conjunction tasks. Experiment 1 used precues, and Experiment 2 used postcues in a yes–no task under valid-, invalid-, and neutral-cueing conditions. Experiments 3 and 4 used a 2-interval alternative forced-choice visual-search task under cued and neutral conditions. Precueing the target location improved performance in feature and conjunction searches; postcueing did not. For the cued targets, the eccentricity effect for features and conjunctions was diminished, suggesting that the attentional mechanism improves the quality of the sensory representation of the attended location. The conjunction set-size effect was reduced but not eliminated. This questions serial-search models that attribute a major role to covert attention in visual search. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.