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Static Analysis and Verification of Steel Fibre Reinforced Concrete Foundation Slabs according to the Austrian Guideline “Fibre reinforced concrete” and DBV (German Concrete Association) Recommendations “Steel fibre reinforced concrete” Steel fibre reinforced concrete is used for foundation slabs of housing structures since many years. The Austrian guideline [1] and the DBV recommendations [2] provide material properties and design values for calculation and verification of steel fibre reinforced concrete structural members. This paper provides a comparative study on foundation slabs taking both guidelines into account. A nonlinear finite element parameter study has been performed in order to verify a simplified static calculation and verification method. This calculation method is based on the yield line theory. This paper concludes with a sample calculation for steel fibre reinforced foundation slabs according to the Austrian and German design recommendations.  相似文献   
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Extracts of Trypanosoma brucei and Trypanosoma congolense were incubated in vitro with nonimmune lymphocytes of mice, rats, guinea pigs, and rabbits in order to test for mitogenic effects or for other characteristics of polyclonal B lymphocyte activators. Trypanosome extracts (TE) were not mitogenic for spleen cells of mice, rats, and guinea pigs in vitro, nor did the parasite extracts alter the mitogenic responses of lymphocytes from these animals to known B- and T-cell mitogens. TE also failed to induce polyclonal antibody synthesis in mouse spleen cell cultures in an in vitro antibody response system, in contrast to the effects of bacterial lipopolysaccharide, a known polyclonal B cell activator. Rabbit spleen cell and peripheral blood lymphocyte cultures, however, were stimulated by TE to undergo blastogenesis in vitro. Incubation of rabbit lymphocytes with phytohemagglutinin (PHA) and TE or anti-rabbit immunoglobulin serum and TE revealed an additive effect only in terms of the TE-plus-PHA culture responses; these findings suggest that a non-PHA responsive lymphocyte population, possibly B lymphocytes, is stimulated by TE in rabbits. The relationship of trypanosome-induced lymphocyte mitogenic stimulation to other immunological dysfunctions occurring in chronic African trypanosomiasis is discussed.  相似文献   
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Protocols for microbial source tracking of fecal contamination generally are able to identify when a source of contamination is present, but thus far have been unable to evaluate what portion of fecal-indicator bacteria (FIB) came from various sources. A mathematical approach to estimate relative amounts of FIB, such as Escherichia coli, from various sources based on the concentration and distribution of microbial source tracking markers in feces was developed. The approach was tested using dilute fecal suspensions, then applied as part of an analytical suite to a contaminated headwater stream in the Rocky Mountains (Upper Fountain Creek, Colorado). In one single-source fecal suspension, a source that was not present could not be excluded because of incomplete marker specificity; however, human and ruminant sources were detected whenever they were present. In the mixed-feces suspension (pet and human), the minority contributor (human) was detected at a concentration low enough to preclude human contamination as the dominant source of E. coli to the sample. Without the semi-quantitative approach described, simple detects of human-associated marker in stream samples would have provided inaccurate evidence that human contamination was a major source of E. coli to the stream. In samples from Upper Fountain Creek the pattern of E. coli, general and host-associated microbial source tracking markers, nutrients, and wastewater-associated chemical detections—augmented with local observations and land-use patterns—indicated that, contrary to expectations, birds rather than humans or ruminants were the predominant source of fecal contamination to Upper Fountain Creek. This new approach to E. coli allocation, validated by a controlled study and tested by application in a relatively simple setting, represents a widely applicable step forward in the field of microbial source tracking of fecal contamination.  相似文献   
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Product design is a cutting-edge area of research. Over the last few years, many papers have been presented dealing with product design. The review focuses on processing of crystalline solids with a particular filed of application in mind and shows how crystallization can be used as tool to generate materials with particular properties and how to tailor these properties by crystallization. The fact that crystallization is a tool for product design will be highlighted by 4 selected examples, dealing with roughness and shelf life of fertilizer granules (case 1 and 2), with micro container as carrier system and, finally, with an alternative tablet forming technique for heat sensitive materials.  相似文献   
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PURPOSE: The primary objectives of the study were to evaluate the efficacy and safety of prolonged oral (PO) etoposide as part of cisplatin-based chemotherapy plus concurrent chest/brain irradiation induction, followed by CAV consolidation, in the treatment of patients with limited-stage small cell lung cancer (SCLC-LD) within a cooperative group setting. METHODS AND MATERIALS: Fifty-six eligible patients with SCLC-LD received three 28-day cycles of cisplatin 50 mg/m2 i.v. (days 1, 8; 29, 36; and 57, 64), PO etoposide 50 mg/m2 (days 1-14, 29-42, and 57-70), and vincristine 2 mg i.v. (days 1, 29, and 57). Thoracic irradiation (TRT) was administered at 1.8 Gy in 25 daily fractions to a total dose of 45 Gy via an AP:PA arrangement, to begin concomitantly with induction chemotherapy. Prophylactic cranial irradiation (PCI) was started on day 15 of induction therapy. Fifteen daily fractions of 2.0 Gy were administered to the entire brain to a total dose of 30 Gy to finish at approximately the same time as TRT. Two 21-day cycles of consolidation cyclophosphamide 750 mg/m2 i.v., doxorubicin 50 mg/m2 i.v., and vincristine 2 mg i.v. (all on days 1 and 22), were given beginning on day 106 or week 16, from the start of induction therapy. RESULTS: Among 56 eligible patients, 93% had SWOG performance status 0-1. All had adequate organ function and had not received prior therapy. The overall confirmed response rate was 46%, including 16% complete responders and 30% partial responders. After a minimum follow-up duration of 17 months, the Kaplan-Meier median progression-free (PFS) and overall survival (OS) were 10 and 15 months, respectively. Two-year survival is 28%. Only 28 of 56 patients (50%) completed chemotherapy per protocol, while 52 of 56 patients (93%) completed radiation per protocol. Eleven patients (20%) discontinued secondary to toxicity and two patients died from treatment. The major toxicity was hematologic. The two deaths were secondary to infection. Of the nonhematologic toxicities, there were 10 cases of pulmonary fibrosis (including one Grade 3) and six cases of pneumonitis (including one Grade 3). CONCLUSION: Concomitant chemoradiation with oral etoposide as part of a platinum-based chemotherapy and TRT induction regimen is toxic. The CR rate is not better than our prior best group-wide experience. The progression-free and overall survival are similar to published trials utilizing short-course i.v. etoposide. As in chemotherapy for extensive-stage SCLC, there is no apparent advantage to prolonged exposure to etoposide, and toxicity resulted in an inferior therapeutic index compared to programs with shortened exposure.  相似文献   
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