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271.
Sediment transport from agricultural land into rivers and reservoirs is a problem within the Czech Republic. This problem was highly accelerated almost 50 years ago during the communist period. At that time strong collectivization was undertaken leading to destruction of traditional landscape patterns, surface outflow, erosion processes intensification and surface water quality deterioration. Thirteen years after political changes erosion problems remain.At the Department of Irrigation, Drainage and Landscape Engineering at the CTU Prague there has been continuous research undertaken in the field of erosion and sediment transport assessment. There are several modelling tools available for this purpose. One of them—USLE (Universal Soil Loss Equation) is commonly used in the Czech Republic for many years at a plot-scale but modern GIS (geographical information systems) tools in computer science allow using it at larger scales. Very important is the validation of this model for two-dimensional topography and GIS routines. Moreover USLE produces only local erosion amount values and has to be completed by another tool to get sediment amounts. For this purpose SDR (sediment delivery ratio) is usually used, applying a lumped approach—total erosion of every watershed is reduced by SDR and by pond’s trapping efficiency. Another available approach is using the Watem/SEDEM model that puts together RUSLE (Revised USLE) and a distributive approach to sediment transport modelling. This has already been used for estimating sediment amount in several catchments of the Czech Republic, but has to be validated as well.At the Dept. of Drainage, Irrigation and Landscape Engineering there are datasets of sediment amount from different reservoirs available and other reservoirs are to be measured soon. As the dataset of various watersheds is expanded, a methodology for sediment amount measurements is needed. The main objective of this paper is to propose a simple methodology to measure the sediment amount within reservoirs as well as to present a review of available methods. The application of the methodology at Vrchlice Catchments (97 km2) case study is presented. Total sediment amounts between 125 000140 000 m3 were measured in Vrchlice reservoir and values of 110 976 m3 (using USLE), resp. 105833 m3 (using Watem/SEDEM) were predicted by the erosion models. For catchments of this scale it is a sufficient validation. 相似文献
272.
Puppo C Chapleau N Speroni F De Lamballerie-Anton M Michel F Añón C Anton M 《Journal of agricultural and food chemistry》2004,52(6):1564-1571
Changes induced by high pressure (HP) treatment (200-600 MPa) on soybean protein isolates (SPI) at pH 3 (SPI3) and pH 8 (SPI8) were analyzed. Changes in protein solubility, surface hydrophobicity (Ho), and free sulfhydryl content (SH(F)) were determined. Protein aggregation and denaturation and changes in secondary structure were also studied. An increase in protein Ho and aggregation, a reduction of free SH, and a partial unfolding of 7S and 11S fractions were observed in HP-treated SPI8. Changes in secondary structure were also detected, which led to a more disordered structure. HP-treated SPI3 was partially denatured and presented insoluble aggregates. A major molecular unfolding, a decrease of thermal stability, and an increase of protein solubility and Ho were also detected. At 400 and 600 MPa, a decrease of the SH(F) and a total denaturation were observed. 相似文献
273.
Urea was split applied to transplanted rice in a greenhouse experiment with two-thirds applied as labeled 15N urea at 15 days after transplanting (DAT) and one-third (not labeled) at 42 DAT to determine the effect of the urease inhibitors phenyl phosphorodiamidate (PPDA) and N-(n-butyl) thiophosphoric triamide (NBPT) on urea hydrolysis, plant uptake, yield, and loss of fertilizer N. An acidifying agent [Al2(SO4)3] and an algicide were used to reduce the floodwater pH and thus slow the degradation of PPDA, keeping it effective for a longer period. Algicide addition extended the effectiveness of PPDA inhibition by about 2 days and increased plant uptake and grain yield significantly over that with urea use alone. Al2(SO4)3 addition extended the effectiveness of PPDA only about 1 day, increased N uptake slightly, but failed to increase grain yield. NBPT effectively slowed urea hydrolysis, more than doubled plant uptake over that with urea alone, and increased grain yield by 38%. Percolation at 0.5 cm per day caused plant N uptake to increase by about 6% in all treatments but it was not essential for the inhibitors to have a beneficial effect. For the first split application, fertilizer losses of 50% from urea were decreased to about 10% by use of NBPT and to 28% with PPDA alone, and by combination of PPDA with the algicide losses were 22%. 相似文献
274.
Anton E. Goodwin Dale K. Cabbiness Horacio A. Mottola 《Water, air, and soil pollution》1977,8(4):467-478
The usefulness of rate information coupled to COD determinations is discussed. A multiparameter system is presented which reflects changes in both the quantity and the overall nature of the oxidizable material. The insight gained by utilization of systems such as the one presented here is illustrated with model compounds and a few samples taken from reactor effluents from a sewage plant. The gain in information is believed to be potentially of use in the planning and improvement of treatments for waste waters. 相似文献
275.
Romero A Beaumal V David-Briand E Cordobés F Guerrero A Anton M 《Journal of agricultural and food chemistry》2011,59(17):9466-9474
Interfacial and emulsifying properties of potato protein isolate (PPI) have been studied to evaluate its potential application to stabilize oil/water emulsions at two pH values (2 and 8). The amount, type, and solubility of proteins and the size of aggregates have been determined in aqueous dispersion. Air-water and oil-water interfacial properties (adsorption, spreading, and viscoelastic properties) have been determined as a function of concentration and pH using soluble phases of PPI. The behavior of PPI stabilized oil/water emulsions has been then analyzed by droplet size distribution measurements and interfacial concentration. PPI exhibits low solubility over a wide range of pH values, with the presence of submicrometer aggregates. The pH value exerts a negligible effect on interfacial tension (oil-water) or surface pressure (air-water) but displays very important differences in viscoelastic properties of the interfacial films formed between oil and water. In this sense, pH 8 provides a major elastic response at oil-water interfaces as compared to pH 2. In relation with this result, a much higher ability to produce fine and stable emulsions is noticed at pH 8 as compared to pH 2. Consequently, there is an evident relationship between the rheological properties of the oil-water interfacial films and the macroscopic emulsion behavior. 相似文献
276.
277.
Anton I Kovács K Fésüs L Várhegyi J Lehel L Hajda Z Polgár JP Szabó F Zsolnai A 《Acta veterinaria Hungarica》2008,56(2):181-186
The objective of this study was to estimate the effect of the thyroglobulin (TG) locus on beef quality traits in some beef cattle breeds and to investigate the effect of the DGAT1 locus on milk production traits in the Hungarian Holstein Friesian population. TG and DGAT1 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. At the TG locus TT bulls showed the highest fat percentage values in the longissimus dorsi muscle (m. longissimus dorsi); the difference between CC and TT genotypes was significant. DGAT1 GC/GC cows had the highest milk, fat and protein yield values. Due to the relatively small number of GC/GC cows the difference proved to be significant only between AA/AA and AA/GC genotypes. 相似文献
278.
Kuemmerle JM Auer JA Rademacher N Lischer CJ Bettschart-Wolfensberger R Fürst AE 《Veterinary surgery : VS》2008,37(2):193-200
Objective— To describe short incomplete sagittal fractures of the proximal phalanx (type Ia P1 fractures) in horses not used for racing and report outcome.
Study Design— Retrospective study.
Animals— Horses (n=10) with type Ia P1 fractures.
Methods— Retrieved data of horses with type Ia P1 fractures were signalment, history and results of orthopedic examination. Radiographs were re-evaluated for position and length of the fracture line, presence of osteoarthritis or subchondral cystic lesions (SCL), periosteal new bone formation and subchondral sclerosis. Conservative treatment (n=4) included box confinement for 2 months followed by 1 month of hand walking. Surgical therapy (n=6) consisted of internal fixation by screws inserted in lag fashion in 5 horses. Concurrent SCL were debrided by curettage via a transcortical drilling approach. In 1 horse, only SCL curettage but not internal fixation was performed. Outcome was assessed on a clinical and radiographic follow-up examination in all horses.
Results— Mean follow-up time was 27 months (median, 13.5 months; range, 9 months to 9 years). All horses treated with internal fixation were sound at follow-up and had radiographic fracture healing. Of the 4 horses managed conservatively, 3 remained lame and only 1 horse had radiographic evidence of fracture healing. Catastrophic fracture propagation occurred in 2 horses not treated by internal fixation, 20 and 30 months after diagnosis, respectively.
Conclusions— Horses with a type Ia P1 fracture treated surgically had a better outcome than those managed conservatively and lack of fracture healing seemingly increases the risk of later catastrophic fracture.
Clinical Relevance— Surgical repair of type Ia P1 fractures should be considered to optimize healing and return to athletic use. 相似文献
Study Design— Retrospective study.
Animals— Horses (n=10) with type Ia P1 fractures.
Methods— Retrieved data of horses with type Ia P1 fractures were signalment, history and results of orthopedic examination. Radiographs were re-evaluated for position and length of the fracture line, presence of osteoarthritis or subchondral cystic lesions (SCL), periosteal new bone formation and subchondral sclerosis. Conservative treatment (n=4) included box confinement for 2 months followed by 1 month of hand walking. Surgical therapy (n=6) consisted of internal fixation by screws inserted in lag fashion in 5 horses. Concurrent SCL were debrided by curettage via a transcortical drilling approach. In 1 horse, only SCL curettage but not internal fixation was performed. Outcome was assessed on a clinical and radiographic follow-up examination in all horses.
Results— Mean follow-up time was 27 months (median, 13.5 months; range, 9 months to 9 years). All horses treated with internal fixation were sound at follow-up and had radiographic fracture healing. Of the 4 horses managed conservatively, 3 remained lame and only 1 horse had radiographic evidence of fracture healing. Catastrophic fracture propagation occurred in 2 horses not treated by internal fixation, 20 and 30 months after diagnosis, respectively.
Conclusions— Horses with a type Ia P1 fracture treated surgically had a better outcome than those managed conservatively and lack of fracture healing seemingly increases the risk of later catastrophic fracture.
Clinical Relevance— Surgical repair of type Ia P1 fractures should be considered to optimize healing and return to athletic use. 相似文献
279.
Eva Kovacikova Anton Kovacik Marek Halenar Katarina Tokarova Lubica Chrastinova Lubomir Ondruska Rastislav Jurcik Eduard Kolesar Jozef Valuch Adriana Kolesarova 《Journal of animal physiology and animal nutrition》2019,103(2):695-703
Amygdalin is one of the most studied secondary metabolites of Prunus genus. It is a cyanogenic glycoside which was initially obtained from the bitter almonds seeds and is a major component of the seeds of plants, such as apricots, almonds, peaches, apples and other rosaceous plants. The views of scientists on the use of amygdalin have been contradictory for many years, partly because toxicokinetics and metabolism of amygdalin still have not been adequately explored. The present in vivo study was designed to reveal whether pure amygdalin intramuscularly injected or apricot seeds oral consumption induce changes in overall health status of rabbit as a biological model. A total of 60 adult rabbits were randomly divided into five groups. The control group received no amygdalin while the two experimental groups E1 and E2 received a daily intramuscular injection of amygdalin at doses 0.6 and 3.0 mg/kg bw. The experimental groups E3 and E4 were fed crushed bitter apricot seeds (Prunus armeniaca L.), at doses 60 and 300 mg/kg bw, mixed with commercial feed for rabbits. Blood collection was carried out after 14 days. Biochemical, haematological and antioxidant enzymes activity analysis were performed and statistically evaluated. A short‐term amygdalin administration had negligible impact on biochemical parameters—mainly level of urea, bilirubin, cholesterol. Haematological profile of rabbits was influenced very slightly—non‐significant platelet count and platelet percentage increase, erythrocytes count and haemoglobin decrease. SOD activity of rabbits decreased significantly (p > 0.05) after apricot seeds consumption (102.3 U/ml) in comparison to control (117.4 U/ml). Differences might be connected to diverse metabolism by different administration routes and at the same time by the presence of other substances in apricot seeds (phytosterols, polyphenols, fatty acids). However, a short‐term consumption had only slight effect on health status of rabbits and at recommended doses did not represent risk for their health. 相似文献
280.
Mayra Anton Dib Saleh Luan Sousa dos Santos Dirlei Antonio Berto Alessandro Borges Amorim Marcos Lívio Panhoza Tse Vladimir Eliodoro Costa 《Journal of animal physiology and animal nutrition》2019,103(3):906-914
Early weaning of piglets causes stress characterized by a decrease in feed intake followed by a decline in growth rates; thus, a fast recovery represents an essential step for proper growth of these animals. Considering that IRMS is a potential tool for non‐destructive sampling and the fact that it provides time‐integrated estimate of assimilated and not just ingested nutrients turned possible its application to evaluate the effects of dietary nucleotides and glutamate on carbon turnover (δ13C) in organs of weanling piglets. At day 0, three piglets were slaughtered (prior to diet switch), the remaining eighty‐four piglets weaned at 21‐day‐old were randomly assigned in a complete block design with a 2 × 2 factorial arrangement of treatments (two Nu levels: 0 and 0.1% and two Glu levels: 0 and 1%), being three piglets per treatment slaughtered on trial days 3, 6, 9, 14, 21, 35 and 49. The samples were analysed by IRMS and adjusted to first‐order equation by a non‐linear regression analysis using NLIN of SAS, in order to establish exponential graphics. After that, the turnover data were submitted to analysis of variance using GLM of SAS. The turnover value (t95%) verified for spleen was faster (p < 0.05) when glutamate was supplemented in diets. For pancreas and liver, the turnover rates were faster (p < 0.05) for the mixture of additives. However, for renal tissue, the turnover rate (t95%) was greater (p < 0.05) for the free additive diet. The results obtained suggest that the mixture of additives was more efficient to develop the digestive tract at post‐weaning phase, taking into account the functional importance of pancreas and liver for nutrients’ digestion and processing. 相似文献