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Michael Herrmann Ulrich Frter‐Barth Manfred A. Bohn Horst Krause Michael Koch Werner Arnold 《Propellants, Explosives, Pyrotechnics》2015,40(6):880-885
Non‐destructive X‐ray diffraction techniques were applied in order to monitor the influence of mechanical and shock‐loading on the microstructure of the plastic‐bonded high explosive KS32. The investigations uncovered damage to embedded coarse HMX crystals and to the binder system HTPB‐IPDI. Damage to the crystals occurred already during the kneading process in terms of deformation twinning. On higher loading between 400 MPa (static) and 480 MPa (dynamic) also crystal fracture was observed. The change in the binder structure was found after both static and dynamic loading, but not in the cured, differently kneaded samples. Moreover, the change in binder structure after dynamic loading was verified by dynamic mechanical analysis, and interpreted as a partial damage of the binder rubber shell around the explosive particles. The results are compared to literature data from imaging techniques. 相似文献
43.
厌氧氨氧化技术用于高氨废水脱氮 总被引:1,自引:0,他引:1
在简要介绍厌氧氨氧化菌生理生化特性的基础上,总结了目前应用厌氧氨氧化的主要工艺及其工程实例,重点分析了厌氧氨氧化技术在处理高氨废水实际工程应用过程中需要解决的关键技术,为厌氧氨氧化技术在污水处理工程中的推广提供技术借鉴. 相似文献
44.
Renata Silvrio Robson Barth Andrea S. Heimann Patrícia Reckziegel Gustavo J. dos Santos Silvana Y. Romero-Zerbo Francisco J. Bermúdez-Silva Alex Rafacho Emer S. Ferro 《International journal of molecular sciences》2022,23(8)
Peptide DIIADDEPLT (Pep19) has been previously suggested to improve metabolic parameters, without adverse central nervous system effects, in a murine model of diet-induced obesity. Here, we aimed to further evaluate whether Pep19 oral administration has anti-obesogenic effects, in a well-established high-fat diet-induced obesity model. Male Swiss mice, fed either a standard diet (SD) or high-fat diet (HFD), were orally administrated for 30 consecutive days, once a day, with saline vehicle or Pep19 (1 mg/kg). Next, several metabolic, morphological, and behavioral parameters were evaluated. Oral administration of Pep19 attenuated HFD body-weight gain, reduced in approximately 40% the absolute mass of the endocrine pancreas, and improved the relationship between circulating insulin and peripheral insulin sensitivity. Pep19 treatment of HFD-fed mice attenuated liver inflammation, hepatic fat distribution and accumulation, and lowered plasma alanine aminotransferase activity. The inguinal fat depot from the SD group treated with Pep19 showed multilocular brown-fat-like cells and increased mRNA expression of uncoupling protein 1 (UCP1), suggesting browning on inguinal white adipose cells. Morphological analysis of brown adipose tissue (BAT) from HFD mice showed the presence of larger white-like unilocular cells, compared to BAT from SD, Pep19-treated SD or HFD mice. Pep19 treatment produced no alterations in mice behavior. Oral administration of Pep19 ameliorates some metabolic traits altered by diet-induced obesity in a Swiss mice model. 相似文献
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The aim of this experiment was to compare social stress, as measured by social behavior and adrenocortical activity, in young dairy goats during the first week after introduction into a herd of adult goats either during the dry period of the herd (i.e., all goats in the herd being pregnant or dry: PD) or shortly after parturition (i.e., all animals lactating or with their kids: LK). Thirty-two young goats that had had no contact with adult goats from the age of 7 wk were introduced into adult goat groups. Adult goats were kept in 2 groups of 36 animals each. Young goats were introduced (in groups of 4 animals each) into each of these 2 groups either during the PD period (2 repetitions) or during LK (2 repetitions); goats with different rearing experience were balanced over introduction periods. Young goats were more often receivers of agonistic social interactions when introduced during PD than during LK. Irrespective of the period of introduction, young goats had other young goats as neighbors more frequently than expected by chance alone, although this was even more distinct during PD. Cortisol metabolite levels increased markedly from baseline during PD, but not after parturition. Rearing showed an effect only on the nearest neighbors, with mother-reared young goats staying closer together. Our results indicate that young goats experience less social stress when being introduced into a herd of adult dairy goats shortly after parturition and with kids still present rather than during the dry period. Whether this effect is due to the period and lactational stage itself or to the presence of kids needs to be tested in future studies. 相似文献
47.
Ligia B. de Almeida‐Muradian Klaus M. Stramm Andreia Horita Ortrud M. Barth Alex da Silva de Freitas Leticia M. Estevinho 《International Journal of Food Science & Technology》2013,48(8):1698-1706
Twenty‐four samples of Apis mellifera honey and twenty‐four samples of Melipona subnitida (Jandaira) honey were collected in the northeast of Brazil. Moisture, hydroxymethylfurfural, free acidity, insoluble solids in water, diastase activity, ashes, electrical conductivity, proteins, lipids, total carbohydrates, energy and sugars were the parameters analysed. The efficiency of the qualitative tests (Fiehe's test, Lugol's reaction, Lund's reaction) was tested. Pollen types and the corresponding plant species were identified in all samples (3 in Apis and 1 in Melipona). Apis mellifera honey samples demonstrated parameters in accordance with the Brazilian Legislation, while the Melipona subnitida honey samples displayed moisture (24.80%) and diastase activity (null) in discordance with the established by the regulation for Apis mellifera honeys. Apis honey samples presented higher values of electric conductivity (284.00 μS cm?1) than the obtained from the Jandaira honey samples (102.77 μS cm?1) as well as a darker colour (26.67 mmPfund) when compared with Jandaira honey (7.00 mmPfund). The concentration of the glucose, fructose and sucrose was higher in the Apis honeys than in the Jandaira honey. The characteristics of the two types of honey were very different, highlighting the need of developing specific legislation for stingless bees' honey. 相似文献
48.
Sudden death is a common complication of myocardial infarction, necrotic pancreatitis and other diseases. Physicians usually neglect the possibility of neurological disorders. 59 cases of sudden death among 314 autopsied cases with neurological diseases were analyzed. The most frequent cause of neurological sudden death was cerebrovascular disease (CVD). It was present in 53 (89.9%) cases. 48 of them had hemorrhagic CVD. 37 of these 48 cases were due to hypothalamic lesions. In 37 cases general autopsy was performed; pathological abnormalities of heart, lungs, stomach etc, were found in 28 of them. In conclusion, the size and location of the lesion correlated with the prognosis of the disease. Concomitant multiple organ damage may deteriorate the lesion. Awareness of sudden death resulting from CVD may elevate the rate of correct diagnosis. 相似文献
49.
CONTEXT: Although blacks receive lower doses of hemodialysis than whites, their survival when receiving dialysis treatment is better than that for whites. Previous studies of the relationship between the dose of dialysis and patient survival have not controlled for differences in patient characteristics. OBJECTIVE: To examine the association of mortality with the dose of hemodialysis for clusters of patients categorized by race and sex. DESIGN: Retrospective analysis of laboratory data and mortality outcomes from 1994, using a national database of hemodialysis patients. PATIENTS: A total of 18144 black and white patients receiving hemodialysis 3 times weekly who either lived the entire year receiving hemodialysis or died. MAIN OUTCOME MEASURES: The fractional reduction of urea in a single dialysis session as the measured hemodialysis dose (urea reduction ratio [URR]) after controlling for race, sex, age, and diabetes mellitus. Mortality was determined by strata of URRs and albumin and creatinine levels. RESULTS: Across all age categories, blacks had lower URRs than whites, and men had lower URRs than women. In an age-adjusted model for evaluating interactions among URRs, race, sex, and diabetes, the association of URR with mortality risk was weak among blacks, particularly black men. After adjustment for age and diabetes, death probability curves were most steep for white women with URR values less than 60%. The death probability curves were least steep for black men. There was no meaningful difference between death probability and albumin or creatinine concentration among the race by sex clusters. CONCLUSION: Using URR, the usual measure of hemodialysis dose, the assumption that the association between dialysis dose and survival is uniform across demographic groups appears incorrect. Comparisons of the quality of dialysis patient care should not rely on URR alone to predict patient survival. 相似文献
50.
WF Bennett 《Canadian Metallurgical Quarterly》1998,14(8):789-796
A historical cohort study was conducted in Misasa town, Tottori prefecture, Japan, where radon spas have been operating for a long time. Misasa town was divided into an elevated radon level area and a control area, with mean indoor radon levels of about 60 and 20 Bq/m3, respectively. In total, 3,083 subjects in the elevated radon level area and 1,248 in the control area, all aged 40 or older on January 1, 1976, were followed up until December 31, 1993, for a mean period of 14 years. The mortality rates from all causes exhibited no difference between the elevated radon level area and the control area for both sexes. No difference was observed in the incidence of all-site cancers (age, period-adjusted rate ratios by Poisson regression, RR = 1.06, 95% confidence interval (CI) 0.79-1.42 for males, RR = 0.90, 95% CI 0.65-1.24 for females), while stomach cancer incidence seemed to decrease for both sexes (RR = 0.70, 95% CI 0.44-1.11 for male, RR = 0.58, 95% CI 0.34-1.00 for female) and lung cancer incidence for males only seemed to increase (RR = 1.65, 95% CI 0.83-3.30 for male, RR = 1.07, 95% CI 0.28-4.14 for female) in the elevated radon level area. Caution is needed in the interpretation of these findings, however, since the individual exposure level was not measured and major confounding factors, such as smoking and diet, could not be controlled in this study. 相似文献