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1.
River Bifurcation Analysis by Physical and Numerical Modeling   总被引:1,自引:0,他引:1  
In the framework of a river regulation design of the Po River Delta (Northern Italy), a study on a large physical model of the bifurcation Po di Goro-Po di Venezia was conducted with the main objective of determining the discharge subdivision rate at the river node, in order to assess the inflow conditions in the Po di Goro River for flood risk analysis. In this context, a two-dimensional depth averaged numerical model was tested against measured values, with reference to the prototype. In this paper a comprehensive analysis and discussion of the results is reported in order to highlight the applicability of numerical models in comparison with physical ones in river engineering applications.  相似文献   
2.
In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promote malignancy. The detailed study of the biochemical and genetic pathways altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function. Recently, the breakpoint gene TCL1, involved in chromosome translocations observed mostly in mature T-cell proliferations and chronic lymphocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors. The murine Tcl1 gene, is similar in sequence to the murine and human MTCP1 gene also involved in T cell leukemias. The murine Tcl1 gene was shown to reside on mouse chromosome 12 in a region syntenic to human chromosome 14. Furthermore, we show that the murine Tcl1 gene is expressed early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells. Characterization of the murine Tcl1 gene will help in developing a mouse model of CLL and would provide the best opportunity to study and decipher the role of TCL1 in malignant transformation.  相似文献   
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Durum wheat (Triticum durum Desf.) has potential as an adjunct in brewing given its agronomic, chemical and technological properties. The aim of this work were to identify the cultivable microflora and evaluate the technological quality of the durum wheat variety ‘Senatore Cappelli’ grown and used by a craft brewery in Sardinia, Italy. The isolated bacterial strains were mainly rhizospheric (Kocuria rizophila, Microbacterium aerolatum and Bacillus pumilus) and associated with the microbiota of wheat (Staphylococcus spp.). None have been reported previously as spoilage species in brewing. The dominant yeast genera were Cryptococcus spp. and Rhodotorula spp., followed by Saccharomyces cerevisiae. The dominant filamentous fungus genera were Alternaria and Rhizopus. Low levels of mycotoxigenic Fusarium spp., Aspergillus spp. and Penicillium spp. were isolated. However, the levels of deoxynivalenol, T2‐HT2, fumonisin, aflatoxin and ochratoxin detected in the malt and grain were below the thresholds defined by European law. Malt obtained from raw grain showed interesting technological properties, but required specific malting parameters different from those of common wheat and barley. These data suggest that the use of locally grown durum wheat in brewing can increase sustainability and reduce costs, while reinforcing the link with the terroir and promoting reduced mycotoxin levels. © 2019 The Institute of Brewing & Distilling  相似文献   
5.
Experimental analysis concerning supercritical flow over a dentated sill in nonsubmerged conditions and the local scour downstream of this sill is presented. In this case, the energy dissipation is incomplete so that a scour control downstream of the hydraulic structure could be required. The use of this type of dissipation device could be needed in cases where the maximum flow depth upstream of the sill must be limited to satisfy physical or structural conditions. This could happen, for instance, in the restoration of stilling basin in gravity dams and at the outlet of diversion systems. Experimental and theoretical results, useful in the design of this type of stilling basin and scour control, are presented in the paper, with an application to the case of the Molato Dam in Italy.  相似文献   
6.
Our objective was to examine the influence of feeding and endogenous GH secretion on circulating IGF-I in colostrum-deprived newborn pigs fed colostrum (n = 4), formula (control, n = 4), or water (n = 4). In another four formula-fed pigs, GH was ablated (GRF-A) with two intravenous injections of a GH releasing-factor antagonist (N-Ac-Tyr1,D-Arg2)-GRF(1-29)-NH2. Blood was serially sampled in all pigs to measure plasma IGF-I and GH profiles. Feeding increased plasma IGF-I concentration two- to fourfold and decreased GH secretion. Despite a more than 80% decrease in the plasma GH in GRF-A pigs, the circulating IGF-I concentration was similar to that in control pigs. In colostrum-fed pigs, plasma IGF-I was higher than that in control pigs, despite equal nutrient intake and lower circulating GH. There were no differences in plasma IGF binding protein (IGFBP)-3 levels among the treatment groups. However, the relative abundance of plasma IGFBP-4 was lower, and that of IGFBP-1 higher, in unfed pigs than in any of the three fed groups. The plasma insulin concentration was not different among fed pigs, but it was lower in unfed pigs. Our results indicate that the circulating IGF-I concentration is more dependent on nutrient intake than on GH in newborn pigs, despite relatively high GH concentrations. However, because the nutrient content in the formula was designed to match that of colostrum, a factor other than nutrient intake and GH was responsible for the maximal increase in circulating IGF-I concentration observed in colostrum-fed pigs.  相似文献   
7.
Establishing fast, simple, low-cost, and efficient sample preparation procedures to determine elements in foodstuffs is a relevant aspect for nutritional and health purposes. For this reason, the recently proposed closed-vessel conductively heated digestion system (CHDS) was evaluated for the digestion of milk powder, chocolate powder, and soluble coffee samples aiming for Ca, Cu, Fe, K, Mg, Mn, Na, and Zn determinations by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS) and Cd, Mo, and Se determinations by inductively coupled plasma mass spectrometry with tandem configuration (ICP-MS/MS). The accuracy was evaluated by analyzing two milk certified reference materials digested by the CHDS and a microwave oven for comparison. When using the CHDS, recoveries for the analytes varied from 91 to 104 %. For microwave digestions, recoveries within the 94–109 % intervals were obtained. The method was then applied to the samples. For comparative purposes, the analytes were also determined in the samples after microwave digestion, and the results between the two digestion systems showed no differences based on a paired t test at a 95 % confidence level. Similar analytical blanks were obtained because quartz digestion tubes were used in both digestion systems. The CHDS with quartz tubes is an interesting alternative for laboratories dedicated to large-scale routine analysis because volatile elements usually found in very low concentrations in food samples such as Cd and Se can also be determined.  相似文献   
8.
In this paper, we report our investigations on five T30175 analogues, prepared by replacing sequence thymidines with abasic sites (S) one at a time, in comparison to their natural counterpart in order to evaluate their antiproliferative potential and the involvement of the residues not belonging to the central core of stacked guanosines in biological activity. The collected NMR (Nuclear Magnetic Resonance), CD (Circular Dichroism), and PAGE (Polyacrylamide Gel Electrophoresis) data strongly suggest that all of them adopt G-quadruplex (G4) structures strictly similar to that of the parent aptamer with the ability to fold into a dimeric structure composed of two identical G-quadruplexes, each characterized by parallel strands, three all-anti-G-tetrads and four one-thymidine loops (one bulge and three propeller loops). Furthermore, their antiproliferative (MTT assay) and anti-motility (wound healing assay) properties against lung and colorectal cancer cells were tested. Although all of the oligodeoxynucleotides (ODNs) investigated here exhibited anti-proliferative activity, the unmodified T30175 aptamer showed the greatest effect on cell growth, suggesting that both its characteristic folding in dimeric form and its presence in the sequence of all thymidines are crucial elements for antiproliferative activity. This straightforward approach is suitable for understanding the critical requirements of the G-quadruplex structures that affect antiproliferative potential and suggests its application as a starting point to facilitate the reasonable development of G-quadruplexes with improved anticancer properties.  相似文献   
9.
Infectious diseases caused by intestinal protozoan, such as Entamoeba histolytica (E. histolytica) and Giardia lamblia (G. lamblia) are a worldwide public health issue. They affect more than 70 million people every year. They colonize intestines causing primarily diarrhea; nevertheless, these infections can lead to more serious complications. The treatment of choice, metronidazole, is in doubt due to adverse effects and resistance. Therefore, there is a need for new compounds against these parasites. In this work, a structure-based virtual screening of FDA-approved drugs was performed to identify compounds with antiprotozoal activity. The glycolytic enzyme triosephosphate isomerase, present in both E. histolytica and G. lamblia, was used as the drug target. The compounds with the best average docking score on both structures were selected for the in vitro evaluation. Three compounds, chlorhexidine, tolcapone, and imatinib, were capable of inhibit growth on G. lamblia trophozoites (0.05–4.935 μg/mL), while folic acid showed activity against E. histolytica (0.186 μg/mL) and G. lamblia (5.342 μg/mL).  相似文献   
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