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31.
Broadcast (distributing a message from a source node to all other nodes) is a fundamental problem in distributed computing. Several solutions for solving this problem in mobile wireless networks are available, in which mobility is dealt with either by the use of randomized retransmissions or, in the case of deterministic delivery protocols, by using conflict-free transmission schedules. Randomized solutions can be used only when unbounded delays can be tolerated. Deterministic conflict-free solutions require schedule recomputation when topology changes, thus becoming unstable when the topology rate of change exceeds the schedule recomputation rate. The deterministic broadcast protocols we introduce in this paper overcome the above limitations by using a novel mobility-transparent schedule, thus providing a delivery (time) guarantee without the need to recompute the schedules when topology changes. We show that the proposed protocol is simple and easy to implement, and that it is optimal in networks in which assumptions on the maximum number of the neighbors of a node can be made  相似文献   
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Little is known on both the composition and mechanism(s) of proteinuria associated with the use of mTOR inhibitors, in particular of Everolimus (E). We characterized urinary proteins utilizing an integrated proteomics approach (quantitative essays, 2‐DE, MALDI‐TOF, Western blot) in 48 renal transplant recipients who were alternatively treated with E (n = 31) or with enteric coated mycophenolic acid (EC‐MPA) (n = 17). Twelve E patients (39%) developed high (>3 g/day) or intermediate proteinuria (1–3 g) compared to four (23%) of the EC‐MPA group. Urinary proteins (p<0.001), β2 microglobulin (p<0.001) and α1microglobulin (p<0.025) were higher in E than in EC‐MPA, appeared more rapidly and were inversely correlated with the day of treatment. Proteomics showed a marked increase of all urinary components in E and EC‐MPA patients, major changes involving typical components of glomerular damage (albumin, α1‐Zn glycoprotein, α2HS glycoprotein, leucin‐richα2‐glycoprotein) and specific bio‐markers for E (clusters of α1‐antitrypsin fragments and monoclonal λ chains). Finally, inter‐α‐trypsin‐inhibitor heavy chain H4 precursor was decreased in E and EC‐MPA urine compared to normal urine. In conclusion, E induced massive and generalized proteinuria of mixed glomerular and tubular origin that was correlated with the start of treatment and reached a nephrotic range in few cases. Specific urinary markers reflect renal alterations related to the transplant or specific alterations associated with the drug.  相似文献   
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Proteinuria is the hallmark of renal diseases and the characterization of the urinary protein composition may become an important source of information for diagnosis and research. So far, protein analysis in urine has been utilized for a generic individuation of site-specific defects (glomerular vs. tubular) but there is a need for an extension of proteomics to specific urinary biomarkers in selected clinical conditions. The identification of fragments of proteins in plasma and urine may increase the spectrum of urinary biomarkers. The unique speculative application so far proposed for protein fragments is nephrotic syndrome, and specifically focal segmental glomerulosclerosis, in which case they reflect intrinsic proteolysis occurring in plasma and represent surrogate biomarkers of the disease activity. Albumin is probably the most studied protein. Several of the albumin fragments present a peculiar distribution of the fingerprint peptide pattern containing both the N-terminal region and the C-terminal domain with a complete lack of any MS signals for the internal sequence region. Their characterization utilizing new strategies based on 2-D nondenaturing electrophoresis is now in progress. Studies on a direct characterization of proteases in plasma and urine will also define the participation of proteases to the genesis of renal diseases.  相似文献   
34.
A compact package for integrated silicon thermal gas flow meters   总被引:1,自引:1,他引:0  
An original packaging method suitable for integrated thermal mass flow sensors is presented. The method is based on a polymethyl-methacrylate (PMMA) adapter, used to convey the fluid flow to the chip areas where the sensing structures are located. Sealing of the adapter was obtained by heating the chip itself to the PMMA glass transition temperature, in order to soften the adapter front surface and improve adhesion. The proposed approach was applied to the packaging of thermal flow meters obtained by post-processing standard integrated circuits. The resulting compact devices have been characterized by measuring the response to a nitrogen flow. Fabrication and testing of a very compact flow sensor is described.  相似文献   
35.
Physical Simulation of Longitudinal Welding in Porthole-Die Extrusion   总被引:2,自引:0,他引:2  
In porthole-die extrusion, the metal flowing through the die has to split up around the webs and then rejoin creating longitudinal welds that extend along the whole profile. The formation and quality of these welds depend on the metal flow around the webs and a number of process parameters such as the thermal and mechanical history stored in the material in the welding area and the temperature and pressure in the welding chamber.The paper presents a new laboratory test principle based on physical-simulation experiments on real materials that proves to be particularly suitable for investigating and modelling longitudinal welds in hot extrusion. In the test, the conditions governing the formation of longitudinal welds in the real industrial process are accurately reproduced and the process parameters affecting the quality of the welds can be individually controlled as well. The results achieved in applications of the test to aluminum alloy AA 6060 are presented with a focus on the operating conditions in the welding chamber that determine the transition from partial to complete longitudinal welding.  相似文献   
36.
The aim of this work was the nutritional evaluation of reformulated dairy products (caciotta-type cheese) and manufactured either with a low-sodium chloride content (different salting time and/or composition of the brine) or low-fat content (different partially skimmed milks). These cheeses were intended for people on low-energy or low-sodium diets. A comparison was made between these new products and three typical Italian cheeses (Provolone, Taleggio and Pecorino Romano). The nutrient content of the products was determined. Amino acids by chromatographic methods, protein digestibility by an enzymatic method and lysine availability determined spectrophotometrically were shown not to be influenced by the salt reduction. The salt reduction also did not affect vitamin contents (riboflavin, retinols, carotenes and tocopherols) measured by HPLC methods, while the reduced fat contents (310 g kg-1, 160 g kg-1 and 87 g kg-1) led to significant decreases in concentrations of fat-soluble vitamins (38% for tocopherols and 7% for total retinols) and a decrease in riboflavin (13%) due to the loss of riboflavin enzymes located on the fat globules (ie xanthine oxidase). Both the typical cheeses and the new formulations represent good sources of calcium and protein. Protein digestibility was affected by the ripening time; in fact, in Pecorino Romano, ripened for 6–9 months it reached 62% in 6 h, whereas in Taleggio and in all caciotta–cheeses it reached only 32–37%. The nutritional profiles of the reformulated caciotta cheese showed that these products could represent a good choice in low-energy and low-sodium diets, but an enrichment of fat-soluble vitamins is advisable in the low-fat products. © 1997 SCI.  相似文献   
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Next-generation malware will adopt self-mutation to circumvent current malware detection techniques. The authors propose a strategy based on code normalization that reduces different instances of the same malware into a common form that can enable accurate detection.  相似文献   
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