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551.
Ginger bagasse from supercritical extraction was hydrolyzed using subcritical water and CO(2) to produce reducing sugars and other low molecular mass substances. Response surface methodology was used to find the best hydrolysis conditions; the degree of hydrolysis and the yield were the two response variables selected for maximization. The kinetic studies of the hydrolysis were performed at 150 bar and temperatures of 176, 188, and 200 degrees C. The higher degree of hydrolysis (97.1% after 15 min of reaction) and higher reducing sugars yield (18.1% after 11 min of reaction) were established for the higher process temperature (200 degrees C). Different mixtures of oligosaccharides with different molecular mass distributions were obtained, depending on the temperature and on the reaction time. The ginger bagasse hydrolysis was treated as a heterogeneous reaction with a first-order global chemical kinetic, in relation to the starch concentration, which resulted in an activation energy of 180.2 kJ/mol and a preexponential factor of 5.79 x 10(17)/s.  相似文献   
552.
The practice of applying seaweed to agricultural fields may provide plant nutrients and improve soil quality in coastal agroecosystems, but little is known about its effects on soil properties or crop production. We conducted a preliminary evaluation of changes in soil biological and chemical properties and sweet corn (Zea mays L.) production using seaweed as a partial source of nitrogen (N) (40–55%) for one growing season, using a preformulated organic fertilizer treatment for comparison. Soil electrical conductivity, potassium (K+), sulfate (SO42-), and active carbon (C) increased with seaweed addition relative to the organic fertilizer, whereas potentially mineralizable N and pH decreased, with effects varying over time. Sweet corn yield and quality were either equivalent to that with the organic fertilizer or improved. The short-term positive (e.g., increased active C) and negative (e.g., increased salt levels) effects on soil quality suggest further evaluation of this practice is justified.  相似文献   
553.
Initial marsh soil development from brackish sediments The initial marsh soil development from brackish sediments was investigated in a transect from the tidal flat to the dike in the southeast Dollart (Lower Saxony, Germany). Oxidized morphological features increased from the tidal flat to the dike. Simultaneously the bulk density increased from 0.57 g cm—3 to 1.12 g cm—3 and the water content decreased from 78.8 % to 54.9 %. The soils closest to the tidal flat were massive, those closest to the dike had a crumble structure. The clay/carbonate ratio increased slightly from 3.3 to 4.8 in the same succession as well as the C/N ratio from 13.9 to 15.6. Likewise the salinity decreased from 7.8 ‰ to 1.5 ‰ and the dominance of Na was replaced by Ca within the pool of exchangeable and soluble cations. The data indicate initial processes of marsh soil development: structure forming, settlement, aeration, salt and lime loss, decomposition and changing ratios of adsorbed cations. Similar to marine developments the soils will enter the terrestrial phase as carbonate containing soils not characterized by the brackish sedimentation conditions. For the initial development of today old marshland soils (”︁Kleimarshes”) from brackish sediments, in contrast, it is likely, that they were already free of carbonate when entering the terrestrial phase. This is explained by long‐term reduction and oxidation of sulfur and low sedimentation rates.  相似文献   
554.
This paper studies the evolution of the determinants of inter‐regional commuting in Italy in the period 1992–2016, during which the labour market has been significantly reformed. To capture the changes in commuting patterns, the analysis of the role of individual, job, firm, and regional characteristics is performed. Specifically, the focus is on the impact of job uncertainty at both micro and macro level, through the analysis of the way the diffusion of temporary contracts has affected the decision to commute for work. The findings suggest that in more recent years workers hired on a temporary contract are more likely to commute to another region. Moreover, the higher the relative share of temporary contracts in the region of residence, the higher the probability of commuting across regions. These findings support the idea that the strong utilisation of (short) temporary contracts represents a push factor, which drives workers away in search of better job opportunities, with potentially negative consequences for poorly performing regions.  相似文献   
555.
556.
The severe mortality of fish due to the infection of megalocytivirus caused significant economic losses. Since 2011, megalocytivirus (giant gourami iridovirus (GGIV)) has become the main pathogen in giant gourami (Osphronemus goramy), particularly in West Java, Central Java and Bali. This study aimed to develop primary cell culture from spleen as the target organ for propagating megalocytivirus in vitro, which was developed by explant method with enzymatic dissociation. Optimization was carried out at incubation temperature, medium and serum concentrations. The origin of the primary cell, cell susceptibility and GGIV pathogenicity were observed. The results showed that the primary cell (GP cells) can grow well in 10% foetal bovine serum L-15 medium at 27°C, which was sufficient for cell growth. PCR and BLAST analyses showed the primary cell was originated from giant gourami. In infected GP cells, cell enlargement and cell rounding were observed. Virus propagated in GP cells was highly virulent when injecting giant gourami in an artificial infection experiment. Intraperitoneal injection of diluted virus supernatant showed 100% mortality in 7–11 days post-injection and 97% mortality in 21 days post-cohabitation, with abnormalities observed in spleen and kidney. In conclusion, GP cell was successfully subcultured for more than 30 passages and susceptible to GGIV.  相似文献   
557.
Mozzarella stretching water (MSW) is a dairy effluent generated from mozzarella cheese production that does not have a real use and is destined to disposal, causing environmental problems and representing a high disposal cost for dairy producers. Spent brewery yeast (SBY) is another promising food waste produced after brewery manufacturing that could be recycled in new biotechnological processes. Aurantiochytrium mangrovei is an aquatic protist known as producer of bioactive lipids such as omega 3 long chain polyunsaturated fatty acids (ω3 LC-PUFA), in particular docosahexaenoic acid (DHA). In this work MSW and SBY have been used to formulate new sustainable growth media for A. mangrovei cultivation and production of DHA in an attempt to valorize these effluents. MSW required an enzymatic hydrolysis to enhance the biomass production. The new media obtained from hydrolysed MSW was also optimized using response surface methodologies, obtaining 10.14 g L−1 of biomass in optimized medium, with a DHA content of 1.21 g L−1.  相似文献   
558.
559.
A 2 year old male mixed breed dog presented with clinical signs of acute cardiac tamponade after being hit by a car. Echocardiography confirmed the presence of pericardial effusion. Pericardiocentesis revealed venous blood that clotted normally, suggestive of an acute lesion involving the right side of the heart. An emergency thoracotomy was performed, and a laceration of the right atrium was identified and repaired. Postoperatively, the dog developed traumatic myocarditis that improved with time and medical management. Six months after surgery, the dog was healthy with no adverse effects of the trauma. The importance of early recognition and the necessity for expeditious surgical management of traumatic right atrial rupture in the dog is illustrated in this report.  相似文献   
560.
The variation within a collection constituted by 36 populations of common bean (Phaseolus vulgarisL.) recently collected in Basilicata region (Southern Italy) was studied. These populations are cultivated in marginal areas of the region mainly for farms' self-consumption. An appreciable variation of seed shape, colour and type of pattern was observed; 34 populations are of climbing growth habit. The frequency of the phaseolin types within the collection was investigated. C, T and S phaseolin types were observed, the type C being predominant (18 of 36 landraces); intra-population variation was detected only for two landraces. Local populations were compared with 28 commercial cultivars widely grown in the Basilicata region and accounting for 80–90% of common bean production. Significant divergences in growth habit and frequency of phaseolin types were observed: 22 cultivars had bush growth habit and 20 showed T phaseolin type. These results stress the urgency of actions devoted to the safeguard of this local germplasm. In fact, the diffusion of alloctonous and not typical germplasm is the first step towards the erosion of useful or valuable genes present in those established local populations.  相似文献   
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