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61.
62.
Gian Mario Bragallini Maria Pia Cavatorta Philippe Sainsot 《Tribology International》2003,36(12):935-941
A strain approach for the design of coated contacts is described, allowing a simple evaluation of the risk of coating failure, once the elastic modulus of the coating and the substrate and the coating thickness are known. Examples are provided for hard and soft coatings. The approach is shown to be particularly useful for hard coatings, where failure is mainly related to tensile longitudinal stresses at the interface. Results from the proposed strain approach compare well with data from a standard stress analysis. Finally, the level of approximation introduced by evaluating the strain field for the reference Hertzian case is discussed, showing that the error introduced is not acceptable. 相似文献
63.
Anna?Pia?Benke Ann-Marleen?Rieps Iris?Wollmann Ioana?Petrova Sabine?Zikeli Kurt?M?llerEmail authorView authors OrcID profile 《Nutrient Cycling in Agroecosystems》2017,107(3):395-411
In temperate regions, legume-based green manures are a key element of organic rotations. However, specialized farms lack sufficient mobile organic fertilizers. To gain a better understanding of the N flows and the nitrogen (N) and phosphorus (P) fertilizer value of different clover-grass-based fertilizers (biogas digestate, compost, silage and fresh clover-grass obtained from clover-grass ley biomass), we assessed their fertilizer value. Nitrogen and P offtake by the ryegrass was used to assess the short-term effects. The data were completed using model calculations to assess the field-to-field N-transfer efficiencies and the overall N-transfer efficiencies. The greatest plant N offtake was achieved with digestates (64%) and the lowest from the compost (6%) and solid farmyard manure (14%). The mineralization rate was positively related to the NH4 +–N/total N ratio (P < 0.01, r2 = 0.82). The model calculations indicate that the overall short-term N-transfer efficiencies are driven by the field-to-field N-transfer efficiency and the field-to-crop transfer efficiency. However, in the long term, model calculations indicate that a high field-to-field N-transfer efficiency is the key strategic approach when aiming to achieve cropping systems with a high overall long-term N-transfer efficiency. Consequently, the results showed that aerobic decomposition (composting) significantly lowered field-to-field as well as field-to-crop N-transfer rates. The relative P use efficiency strongly differed among the fertilizers. In particular, freshly cut clover-grass and solid manure increased P availability and led to an increase of plant P offtake that was higher than the amount of P supplied. 相似文献
64.
Ghiggeri GM Bruschi M Musante L Candiano G Boccardi C Citti L Rastaldi MP Mangraviti S Rosso G Larti A Rosati A Urbani A Gusmano R Bertoni E Salvadori M 《Proteomics. Clinical applications》2008,2(9):1327-1337
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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66.
Nicola Costantino Mariagrazia Dotoli Marco Falagario Maria Pia Fanti Agostino Marcello Mangini Fabio Sciancalepore Walter Ukovich 《Computers & Industrial Engineering》2013
The paper addresses the optimal design of the last supply chain branch, i.e., the Distribution Network (DN), starting from manufacturers till the retailers. It considers a distributed system composed of different stages connected by material links labeled with suitable performance indices. A hierarchical procedure employing direct graph (digraph) modeling, mixed integer linear programming, and the Analytic Hierarchy Process (AHP) is presented to select the optimal DN configuration. More in detail, a first-level DN optimization problem taking into account the definition and evaluation of the distribution chain performance provides a set of Pareto optimal solutions defined by digraph modeling. A second level DN optimization using the AHP method selects, on the basis of further criteria, the DN configuration from the Pareto face alternatives. To show the method effectiveness, the optimization model is applied to a case study describing an Italian regional healthcare drug DN. The problem solution by the proposed design method allows improving the DN flexibility and performance. 相似文献
67.
Jussi Loponen Pia Laine Tuula Sontag-Strohm Hannu Salovaara 《European Food Research and Technology》2007,225(1):105-110
Oat bran fermentation (OBF) is used to produce non-dairy yogurt-type products. Such products may be designed being rich in
probiotic bacteria and/or dietary-fibre. Oat bran is, however, also rich in proteins, especially 12 S globulins. Understanding
the behaviour of globulins in OBF would thus offer a basis for further exploitation of proteins in the product design. The
behaviour of oat globulins was monitored during a model OBF in order to study changes in protein solubility and possible protein
hydrolysis. Proteins were extracted from OBF samples with a buffered and a non-buffered extraction procedure. The extracts
were analyzed with SDS-PAGE and a Lowry assay. Combined effect of pH and NaCl-concentration on the solubility of oat globulin
isolate was studied. The solubility of oat globulins decreased during OBF; this appeared as their shift from the salt-soluble
fraction to the residual protein fraction. The shift in oat globulin solubility was due to the acidifying conditions present
in OBF, which lead to the unfolding of globulins and also apparently induced protein aggregation. No major protein hydrolysis
was observed during OBF. 相似文献
68.
69.
70.
Peter Lindblad Kjell Christensson Pia Lindberg Alexander Fedorov Fernando Pinto Anatoly Tsygankov 《International Journal of Hydrogen Energy》2002,27(11-12)
We have analyzed the filamentous cyanobacterium Anabaena PCC 7120 (wildtype) containing one nitrogenase, one uptake hydrogenase and one bidirectional hydrogenase and its hydrogen uptake deficient mutant AMC 414 for their H2 production capacities. Anabaena PCC 7120 and AMC 414 had similar growth rates in turbidostat mode with increased growth rates at higher light intensity. Rates of C2H2 reduction were similar for both strains. In contrast to the wildtype, AMC 414 produced H2 in a PhotoBioReactor (PhBR) using air as the lifting gas. The rate of H2 production increased with light intensity and was not even saturated at 456 μEm−2 s−1. H2 production increased significantly when replacing the air with argon. The maximal H2 production during outdoor conditions was recorded using AMC 414 with a peak at 14.9 ml H2 h−1 l−1. Despite the relatively high production, maximal efficiency of solar energy to H2 conversion was only 0.042%. A molecular method was developed to analyze the relative abundancies of weight and mutant in competition experiments in the PhBR. 相似文献