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11.
As the use of high performance textiles has grown, the need for chemical finishes to provide the fabric properties required in the special applications has grown accordingly. In this project, a series of water dispersible polyurethanes dispersion (CS-PUs) with multipurpose performance profile was developed using isophorone diisocyanate (IPDI), polyethylene glycol (PEG), 2,2-dimethylol propionic acid (DMPA) and chitosan (CS) for textile applications. In two step synthesis process, NCO functional PU prepolymers prepared by reacting IPDI, PEG, and DMPA were extended with varying molar quantities of chitosan followed by structural characterization through FTIR. The prepared CS-PU dispersions were applied onto the dyed and printed poly-cotton blend fabrics. The performance behavior of the treated fabric in terms of crease recovery, tear strength, tensile strength, and antibacterial properties was evaluated by applying standard test methods. These investigations show that the CS-PU dispersions can be applied as antibacterial textile finishes with significant improvement in the physical and mechanical properties of poly-cotton fabrics.  相似文献   
12.
The study presents the first report on biocontrol of brown sheath rot disease of rice caused by Pseudomonas fuscovaginae using rhizo-bacterial isolate Bacillus amyloliquefaciens Bk7. Four potential bioactive antagonists were selected from 120 Bacillus isolates. Results obtained from in vitro laboratory assay showed that rhizosphere bacterial strain Bk7 and its metabolites significantly suppressed the growth of Pseudomonas fuscovaginae with 93 % efficacy. In glasshouse experiments, strain Bk7 exhibited biocontrol efficacy of 76.6 % by reducing the disease incidence to 16.9 %, compared to 72.8 % observed in control treatment. In addition, the isolate Bk7 showed the growth promotion efficacy of plant height (GPE, 46.4 %) and fresh weight (GPE, 84.3 %). Characterization of isolate Bk7 revealed its strong capability for biofilm formation, inorganic phosphate solubilization and production of high amounts of Indole-3 acetic acid, siderophores and ammonia in vitro. Results obtained from multiplex PCR assay confirmed the presence of five lipopeptide biosynthetic gene markers (srfAA, fenD, bmyB, bacA and ituC) in the genome of strain Bk7. Moreover, Real-time qPCR of these genes demonstrated that surfactin, iturin and bacylisin coding genes were highly expressed in response to P. fuscovaginae exposure in vitro. Rhizosphere bacterial strain Bk7 was identified as B. amyloliquefaciens strain Bk7 based on the analysis of 16S rDNA internal transcribed spacer sequences and a fatty acid methyl ester analysis. The results obtained from this study showed the potential usefulness of Bk7 as a biocontrol agent in disease control of rice brown sheath rot.  相似文献   
13.
An experiment was conducted to investigate the effects of three levels (0%, 3% and 6%) of poultry by‐product meal (PBM) with or without protease on broiler growth, carcass characteristics and nutrient digestibility from 1 to 35 days. Two hundred and forty birds (n = 240) were fed equi‐caloric and equi‐nitrogenous (ME 2850 kcal/kg; CP 20%) diets throughout the experiment. The enzyme supplementation increased feed intake (< .01) and body weight gain (< .01), but feed:gain remained unaffected (p > .05) from 1 to 21 days. Increasing level of PBM decreased feed intake (< .05), but body weight gain was improved (< .05) at 3% PBM level during 1 to 21 days. The feed:gain was improved (< .05) in birds fed diets containing 3% PBM. The feed:gain was also improved in birds fed diets containing 3% PBM from 1 to 35 days. However, feed intake and body weight gain in birds fed diets containing PBM remained unaffected. An interaction (< .01) on feed intake between enzyme and PBM was noticed during 1 to 21 days. However, no interaction was recorded for body weight gain and feed:gain. The per cent carcass yield improved (< .01) in birds fed diets supplemented with enzyme. The per cent breast meat yield was depressed (< .005) in birds fed diets containing PBM. Apparent metabolizable energy (< .001), nitrogen retention (< .01), apparent metabolizable energy corrected for nitrogen (< .001), and apparent digestibility coefficient for nitrogen (< .01) improved in birds fed diets containing enzyme; however, a reverse was noticed in those fed diets containing only PBM. In conclusion, inclusion of 3% PBM along with supplementation of exogenous protease improved performance and nutrient digestibility in broilers.  相似文献   
14.
Gesunde Pflanzen - Biochar (BC) is known to enhance plant growth and may activate plant resistance to various soil borne pathogens. In this experiment, the rice husk (RH) BC was combined with...  相似文献   
15.
Simultaneous measurement of the renal clearance of endogenous creatinine and exogenous inulin in eight sheep showed similar mean +/- SD (n = 32) values of 13.8 +/- 1.3 and 13.2 +/- 2.0 ml min-1 (10 kg)-1 bodyweight respectively. These results demonstrate that the renal clearance of endogenous creatinine is a satisfactory measure of glomerular filtration rate (GFR) in sheep. The plasma concentrations of endogenous creatinine and urea were significantly higher because of haemoconcentration during summer, resulting in lower GFR than in winter. Besides glomerular filtration and back diffusion, the renal handling of urea in sheep seems to involve mechanisms analogous to active tubular secretion.  相似文献   
16.
Pharmacokinetics and renal clearance of ampicillin were investigated in 13 sheep, following one single oral dose of 750 mg. A peak concentration in plasma 0.38 +/- 0.04 microgram/ml (mean +/- SEM) was achieved 95.3 +/- 5.95 min after drug administration. Absorption half-life was 44.4 +/- 4.4 min. The area under the plasma concentration curve was 94.6 +/- 4.5 micrograms.hour.ml-1, while in the case of urine it was 370.5 +/- 28.3 micrograms.hour.ml-1. Biological half-life of ampicillin was 110 +/- 3 min, with an elimination rate constant of 0.0064 +/- 0.0002 min-1. The values for volume of distribution and total body clearance were 8.2 +/- 0.71/kg or 52.0 +/- 4.2 ml/kg/min, respectively. The priming and maintenance doses, using MIC as 0.05 microgram/ml, were suggested to be 8.8 or 8.4 mg/kg, respectively, at an 8-h interval. For MIC of 0.5 microgram/ml, this dose should be 10 times higher. Renal clearance of ampicillin seemed to involve active tubular secretion. Renal excretion indicated either extensive metabolism or excretion through routes other than kidneys.  相似文献   
17.
Plants respond to their external environment to optimize their nutrition and production potential to minimize the food security issues and support sustainable agriculture system. Phosphorus (P) is an important nutrient for plants and is involved in plant metabolic processes. It is mostly available as orthophosphate and has a tendency to form complexes with cations. It has low mobility in soil, thus becoming unavailable for plant uptake that causes a reduction in plant growth and yield. Besides free P, phytate is the major form of organic P in soil and plant tissues. Phytases obtained from different sources, that is, plants, animals, and microorganisms, catalyze the hydrolysis of phytate and release available forms of inorganic P. The knowledge of mechanisms involved in catalytic activity of phytase obtained from microorganisms in soil is limited. This review summarizes the role of microbial phytase in releasing organic P by hydrolysis of phytate and factors affecting its activity in the soil.  相似文献   
18.
The present investigation deals with purification and thermal characterization of an acid invertase produced by Fusarium solani in submerged culture. The maximum enzyme activity (9.90 U mL(-1)) was achieved after 96 h of cultivation at pH 5.0 and 30 degrees C in a basal medium containing molasses (2%) as the carbon and energy source supplemented with 1% peptone. Invertase was purified by ammonium sulfate fractionation and column chromatography on DEAE-cellulose and Sephadex G-200. The purified enzyme was proven to be homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular mass of the enzyme was 65 kDa. The optimum pH and temperature for activity were 2.6 and 50 degrees C, respectively. The Km value for sucrose was 3.57 mM with an activation energy of 4.056 kJ mol(-1). Enthalpies of activation (DeltaH) were decreased while entropies (DeltaS) of activation increased at higher temperatures. The effects of alpha-chymotrypsin and 4 M urea were tetraphasic with periodic gain and loss of enzyme activity. A possible explanation for the thermal inactivation of invertase at higher temperatures is also discussed.  相似文献   
19.
Multiparent advanced generation intercross (MAGIC) populations have recently been developed to allow the high-resolution mapping of complex quantitative traits. This article describes the development of one MAGIC population and verifies its potential application for mapping quantitative trait loci (QTLs) in Brassica juncea. A total of 170 RILs were genotyped using 346 intron length polymorphism (ILP) polymorphic markers. The population lacks significant signatures of population structure that are suitable for the analysis of complex traits. Genome-wide association mapping (GWAS) identified three major glucosinolate (GSL) QTLs of QGsl.ig01.1 on J01 for indole GSL (IG), QGsl.atg09.1 on J09 and QGsl.atg11.1 on J11 for aliphatic GSL (AG) and total GSL (TG). The candidate genes for QGsl.ig01.1, QGsl.atg09.1 and QGsl.atg11.1 are GSH1, GSL-ALK and MYB28, which are involved in converting glutamate and cysteine to γ-EC, the accumulation of glucoraphanin and the whole process of AG metabolism, respectively. In addition to its QTL mapping purpose, the MAGIC population could also be potentially utilized in variety development by breeders.  相似文献   
20.
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