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91.
Heterologous conjugates of wheat arabinoxylan and beta-casein were prepared via enzymatic cross-linking, using sequential addition of the arabinoxylan to a mixture of beta-casein, peroxidase, and hydrogen peroxide. The maximal formation of adducts between the beta-casein and the feruloylated arabinoxylan was reached at a protein-to-arabinoxylan ratio of 10:1, in combination with a molar ratio hydrogen peroxide to substrate of 2:1 and a molar protein-to-enzyme ratio between 10(2) and 10(4). The protein-arabinoxylan adducts were separated from the arabinoxylan homopolymers by size exclusion and anion exchange chromatography. The molar ratio protein:arabinoxylan in the purified conjugates varied between 0.1 and 5.6. This is the first report on the large-scale enzymatic preparation of heterologous protein-arabinoxylan conjugates.  相似文献   
92.
Solís  G. J.  Alonso  E.  Riesco  P. 《Water, air, and soil pollution》2002,140(1-4):139-156
A new European Union legislation on sludge treatment isbeing introduced that will replace the one currently in force.The control of heavy metals is an important aspect of this newlegislation. The most common methodology to examine the metalcontent of sludges is determination of total metal contentafter total or pseudo total digestion of the sludge samples.Nevertheless, this kind of analysis is not informative on theavailability or mobility of the metals; a metal speciationanalysis is therefore required. In this study, sludge samplesfrom conventional activated sludge wastewater treatment plants(WWTP) were collected at different stages of an anaerobicsludge treatment process. In these samples, the total metalcontent and the distribution of metal species were determined(Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ti, Zn) followinga protocol of sequential extraction. Only 14% of the metalwas present in readily available forms in the treated sludges.In composted sludges, this value dropped to 6%.  相似文献   
93.
Nitrogen uptake of kohlrabi, estimated by growth stages and an empirical growth model Some fertilizer recommendation systems for field vegetables are based on estimated nitrogen uptake curves. The estimation of nitrogen uptake should be as accurate as possible. Therefore 3 estimation methods and their accuracy (standard error of difference between measured and estimated values, sd) are compared. Comparisons were carried out with measured nitrogen uptake curves of kohlrabi (Brassica oleracea var. gongylodes L.) from 16 field experiments. The use of observed growth stages resulted in the smallest estimation error (sd = 14 kg N · ha?1). This method is recommendable because it is accurate and easy to use. Estimations by applying an empirical nitrogen uptake model (sd = 16 kg N · ha?1) are more complicated. The estimation based on time after planting is easy to use but showed the largest estimation error (sd = 28 kg N · ha?1).  相似文献   
94.

Purpose

The El Granero reservoir is the last reservoir of the Rio Conchos before it joins the Rio Grande at the Mexico–USA border. This reservoir, together with the San Marcos reservoir, is located in the arid region of Chihuahua, Mexico. High, naturally occurring radioactivity levels, as well as high arsenic (As) concentrations, have been found in both reservoirs. The main goal of this research was to establish the spatial and temporal distribution of trace and radioactive elements in surface sediments and cores collected from these reservoirs.

Materials and methods

Sediment cores were dated using 210Pb and 137Cs measurements and applying the constant rate of supply (CRS) model. Major, trace, and radioactive elements were determined in surface samples and three sediment cores. Radioactive elements were determined by both alpha and gamma spectrometry. Major and trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) using the EPA 3051a method. Enrichment factors (EF), contamination factors (CF), and pollution load indexes (PLI) were calculated in order to identify the human impact in both reservoirs, whereas the chemical index weathering (CIW) was used to assess differences in the degree of weathering.

Results and discussion

High uranium (U) enrichment (EFs?=?24.9–54.7) was observed in core layers at the San Marcos reservoir, while in surface sediments, this enrichment was lower. The high variability of lead (Pb) and As in sediment cores from the Granero reservoir was attributed to human influence. Arsenic and Pb enrichment differences between entry and exit sediment cores were explained by the filtering capabilities of the elongated shape, the topography, and the presence of plants on the reservoir’s bed. The highest PLI was found at the entrance core of the Granero reservoir.

Conclusions

The natural element concentration levels of As, Pb, and U were established at the Granero reservoir. High EFs for As and Pb suggest an anthropogenic origin of these pollutants at specific time intervals. High U concentrations in the San Marcos area are explained as naturally occurring. The concentrations of As in most of the studied sediments could pose a risk to human health by As ingestion, since they are above the probable effect level (PEL).
  相似文献   
95.
With the aim of finding methods that could constitute a solid alternative to melissopalynological and physicochemical analyses to determine the botanical origin (floral or honeydew) of honeys, the free amino acid content of 46 honey samples has been determined. The honeys were collected in a small geographic area of approximately 2000 km(2) in central Spain. Twenty-seven honey samples were classified as floral and 19 as honeydew according to their palynological and physicochemical analyses. The resulting data have been subjected to different multivariant analysis techniques. One hundred percent of honey samples have been correctly classified into either the floral or the honeydew groups, according to their content in glutamic acid and tryptophan. It is concluded that free amino acids are good indicators of the botanical origin of honeys, saving time compared with more tedious analyses.  相似文献   
96.
This investigation studied the evolution of amines in red wines made with Merlot variety, during aging in American oak barrels (Quercus alba) and in French oak barrels (Quercus sessilis) from the Allier and Nevers regions. From the results obtained it was observed that the evolutions of the amines were similar in all three types of oak woods. Histamine and tyramine were produced at the beginning of the aging process, although they were not accumulated in the wines, probably due to their degradation. Putrescine was the most abundant amine in the wines; its concentration increased to an important extent during aging as it did not undergo degradation. The concentration of cadaverine increased slightly at the first stage of aging and, like putrescine, did not degrade at all. The volatile amines showed slight variations during aging, although in no cases were high accumulations observed in the wines. Dimethylamine and isobutylamine were degraded during storage in the barrels.  相似文献   
97.
The nutritional effects in the rat of raw lentil meal or its fractions have been evaluated in three feeding trials. Growth, gain/feed ratio, apparent N digestibility, and N retention were significantly (p < 0.05) reduced by the inclusion of whole lentil meal, dehulled lentil meal, or ethanol-extracted lentil meal as the sole source of protein in the diet. Pure lentil lectin and lectin-depleted albumin proteins had no significant negative effect on nutritional performance. In contrast, growth, gain/feed ratio, protein conversion efficiency, N digestibility, and N retention were significantly (p < 0.05) reduced by diets containing lentil globulins or lentil hulls. The poor nutritional quality of raw lentil meal for rats is therefore likely to be primarily due to the combined effects of these two components.  相似文献   
98.
An indirect sandwich enzyme-linked immunosorbent assay (ELISA) has been used for vesicular stomatitis virus (VSV) typing using sets of monovalent and polyvalent rabbit/guinea pig antisera for identification of VSV types New Jersey (VNJ) and Indiana (VIND). The VIND polyvalent antiserum (VIND-P) detects any strain of the 3 subtypes of the VIND type (VIND-1, VIND-2, and VIND-3) with the same strong reactivity. It is also possible to subtype the VIND strains using VIND-P rabbit antiserum as capture antibody and monovalent VIND-1, VIND-2, or VIND-3 guinea pig antisera as detector. The ELISA proposed has about 10 times more sensitivity and provides 10% more positive results than does the complement fixation 50% (CF50) test when epithelial samples are tested.  相似文献   
99.
In human tuberculosis (Mycobacterium tuberculosis), molecular epidemiology has accurately indicated the risk factors involved in active transmission of the disease, by comparing individuals whose isolates belong to a cluster with patients whose strains are considered unique. Nevertheless, this application has not been used in bovine tuberculosis (Mycobacterium bovis). Our study describes the integration of epidemiological data into molecular classification data on M. bovis isolates. These were isolated from wild ungulates in Extremadura (western Spain) with the objective of detecting the risk factors linked to the association of strains in clades, which are indicators of the active spread of the disease. The molecular markers used were spoligotyping + VNTR typing (loci: VNTR 2165, VNTR 2461, VNTR 0577, VNTR 0580, VNTR 3192 VNTR 2163a and VNTR 2163b) on a population of 59 M. bovis strains isolated from deer (Cervus elaphus), 112 from wild boar (Sus scrofa), six from bovines, 28 from pigs and 2 from goats (n = 207). Epidemiological variables included the animal species from which the strain was isolated, pathological condition of the host (incipient lesion, early and late generalisation), date of sampling (during or after the reproductive period) and hunting season. Bivariant analysis was used to establish the risk factors connected to the association of strains and later, the variables were evaluated by means of logistic regression. Molecular typing grouped a total of 131 strains (64.21%) in 28 clusters and 76 isolates shows unique profiles. The association of strains was connected to the appearance of macroscopic lesions during the reproductive period (O.R. 4.80; 95% CI 1.09–22.99, P < 0.005), showing a possible higher transmission during the courting period. This happened mainly during the last hunting season analysed (2002–2003, O.R. 3.69; 95% CI 1.27–11.9, P < 0.05), clashing with the time of higher prevalence of the disease in wild ungulates. Active spread was not connected to any species in particular, or to any concrete pathological condition.  相似文献   
100.
OBJECTIVE: To evaluate the use of subdermal plexus skin flaps for closing defects after excision of cutaneous and subcutaneous tumors in dogs and to compare outcome of flaps secured with sutures and those secured with butyl-cyanoacrylate and intermittent sutures. STUDY DESIGN: Clinical study. ANIMALS: Fifteen dogs. METHODS: After excision of cutaneous or subcutaneous tumors the skin defect was reconstructed by random flaps based on the subdermal plexus. Flap skin edges were apposed with simple interrupted 4-0 monofilament nylon sutures (group 1; 5 dogs) or nylon sutures alternated with butyl-cyanoacrylate adhesive (group 2; 10 dogs). Flaps were evaluated every 48 hours when bandages were changed, until complete healing. RESULTS: Random flaps based on the subdermal plexus were effectively used to close wound defects; mean flap survival was 89%. Partial flap necrosis occurred in 4 dogs. Wound margins apposed with butyl-cyanoacrylate had thinner and more esthetic scars than sutured margins. CONCLUSION: Random flaps based on the subdermal plexus proved to be versatile for covering limb wounds after excision of cutaneous or subcutaneous tumors. Mean survival rate was comparable to that reported for axial pattern flaps. Butyl-cyanoacrylate adhesive was easy to apply, allowed accurate margin apposition with good cosmetic outcome and reduced sutures needed. CLINICAL RELEVANCE: Cyanoacrylate adhesive should be considered in lieu of suture closure to secure random skin flaps based on the subdermal plexus in dogs.  相似文献   
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