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121.
Changes in the structural composition of fulvic acids were followed during composting of tannery solid waste after neutralization of its acidity by ammonium or by lime. Different techniques (elemental analysis, Fourier transform infrared (FTIR), 13C-NMR spectroscopy) were applied. During both trials of composting, a decrease of carbon and increase of oxygen occurred, which originated from strong microbial oxidation and preservation of some structures during composting. In fact, Nuclear Magnetic Resonance (NMR) spectra showed the preservation of anomeric or tannin structures around 105 ppm. The infrared (IR) spectral data showed a decrease in the intensity of COO? group bands (1623 and 1399.5 cm?1); this is correlated with a decrease of fulvic acid levels. The variations observed in NMR spectra could be explained by the involvement of COO? groups of certain structures in polycondensing to form humic acids. The fulvic acids remain composed of less polycondensed structures with a –COOH extremity, as supported by a decrease of the C/H ratio. In contrast, in the trial with addition of ammonia a slight increase in N content occurred, a decrease in absorbance in the 1730–1000 cm?1 regions compared to the absorbance around 3400 cm?1, and a strong decrease of carboxyl carbon in the 13C-NMR spectra.  相似文献   
122.
Vernalization and photoperiodism are two important physiological processes related to yield of many cool-season annual crops. The flowering response of 20 flax (Linum usitatissimum L.) genotypes to two vernalization regimes (vernalized and unvernalized) and two photoperiod treatments (10 and 14 h) was evaluated in a growth chamber study in 2010 and 2011. The results suggest that photoperiod, vernalization, and genotype all had an effect on earliness as measured by days to anthesis. Unlike flax grown in the Upper US Midwest and Canada, Texas flax is grown in the fall due to high spring and summer temperatures. Genotype interaction was observed with both vernalization and photoperiod. Specifically, flax genotypes from Texas (winter type) were sensitive to both vernalization and photoperiods for flowering. Texas genotypes delayed anthesis for 7 days or more in unvernalized seedlings, whereas flowering time of most other spring grown flax genotypes was unaffected by the vernalization treatments. Texas genotypes also delayed anthesis for 12 days or more under vernalized and short day conditions, whereas most other genotypes were not influenced by photoperiodism in vernalized seedlings. The selection for vernalization and photoperiodic sensitivity in Texas genotypes and introgression of these traits into recently adapted spring grown genotypes is needed for development of high yielding flax genotypes for southern Great Plains production areas.  相似文献   
123.
Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of Johne's disease in dairy cattle. Genotyping of MAP is useful to gain a better understanding of the origin of infection, to evaluate regional control programs, to improve diagnostics, and to develop vaccines. In this study 91 MAP isolates mainly from symptomatic dairy cattle in Rhineland-Palatinate (RP, Germany), its neighbor federal states, and Luxembourg were genotyped using Mycobacterial Interspersed Repetitive Units-Variable Number Tandem Repeat (MIRU-VNTR) and Multilocus Short Sequence Repeats (MLSSR). MIRU-VNTR and MLSSR produced 11 and 6 different genotypes among the 91 isolates, respectively. The combined analysis of both methods produced 25 genotypes with an index of discrimination (D) of 0.93 (95% CI: 0.91-0.95). The results revealed the genetic diversity of MAP and the dominance of two MAP genotypes commonly found in Europe, showed the usefulness of MAP genotyping in studies at a regional scale, and provided useful information for control initiatives in RP.  相似文献   
124.
Traditionally, high amylose starch (HAS) from maize (Zea mays L.) has been mainly used as an ingredient in gum candies and as an adhesive for corrugated cardboard. Two recent advances have increased interest in the use of HAS. The first one has been the development of starch-based biodegradable thermo plastics. Second, high amylose maize is a source of resistant starch (RS), a type of starch that resists digestion. As a food additive, consumers can benefit from added RS since it will lower the glycemic index and the risk of colon cancer in accordance with recent research in food science. Normal maize has about 25% amylose starch. A maize inbred line, GEMS-0067 (Reg. no GP-550, PI 643420) possesses high amylose modifier gene(s) that, together with the recessive amylose extender (ae) gene, raises the starch amylose percentage to at least 70%. The objective of this study was to determine the gene effects, non-allelic interactions and heritability of high amylose content in maize using Bogyo’s triploid model. Nine populations were derived from a cross between H99ae, a maize inbred line with 55% amylose starch, and GEMS-0067. Data were collected from two locations in Missouri (MO) and South Dakota (SD) over 2 years (2005 and 2006). Incomplete dominance explained some of the inheritance of HAS. Maternal effects were also detected. The triploid models for MO and SD were separately established based on the corresponding data in 2005 and 2006. The additive and type 1 dominance effects in MO, and the additive, type 1 dominance, type 2 dominance, and additive × additive in SD were significantly different from zero meaning that those effects played an important role in amylose synthesis. Both broad-sense and narrow-sense heritabilities were high indicating that high amylose content could be effectively selected for in a segregating population.  相似文献   
125.
Egyptian broomrape is a root holoparasitic plant that causes severe damage to tomato in Iran. Experiments were conducted in 2013 to investigate the effect of silicon (Si) nutrition on broomrape response in tomato. Si concentration significantly delayed first appearance of broomrape and decreased number of tubercles in both cultivars, although the magnitude of reduction varied with cultivar and Si concentration. Broomrape infection significantly decreased root and shoot dry weights of tomato cultivars. However, Si nutrition at high concentration considerably reduced damage severity of broomrape compared to the treatment that received no Si. Infection of tomato with broomrape resulted in significant increase in peroxidase and catalase activity in the roots of resistant cultivar which led to enhanced crop resistance to oxidative stress and improved growth in this cultivar.  相似文献   
126.
The thermal treatment method was employed to achieve higher homogeneity of calcium ferrite (CaFe2O4) and Poly (vinyl alcohol) (PVA) nanocomposites. The influences of phase transformation on physical and biological properties of calcined specimens were investigated by various experimental techniques including X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), high resolution Field emission scanning electron microscope (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Heat treatment was conducted at temperatures between 723 and 923 K, so that a phase transformation occurred from cubic to orthorhombic spinel structure at 923 K. The chemical analysis of the PVA/CaFe2O4 nanocomposite was performed by energy dispersion X-ray analysis (EDXA), demonstrated the PVA/CaFe2O4 nanocomposites contained the elements of C, Ca, Fe, and O. The formed nanocomposites exhibited ferromagnetic behaviors which were confirmed by using a vibrating sample magnetometer (VSM). The calcined specimens were carried out to an antimicrobial or antifungal test.  相似文献   
127.
Heat stress adversely affects wheat production in many regions of the world and is particularly detrimental during reproductive development and grain-filling. The objective of this study was to identify quantitative trait loci (QTL) associated with heat susceptibility index (HSI) of yield components in response to a short-term heat shock during early grain-filling in wheat. The HSI was used as an indicator of yield stability and a proxy for heat tolerance. A recombinant inbred line (RIL) population derived from the heat tolerant cultivar ‘Halberd’ and heat sensitive cultivar ‘Cutter’ was evaluated for heat tolerance over 2 years in a controlled environment. The RILs and parental lines were grown in the greenhouse and at 10 days after pollination (DAP) half the plants for each RIL received a three-day heat stress treatment at 38°C/18°C day/night, while half were kept at control conditions of 20°C/18°C day/night. At maturity, the main spike was harvested and used to determine yield components. A significant treatment effect was observed for most yield components and a HSI was calculated for individual components and used for QTL mapping. QTL analysis identified 15 and 12 QTL associated with HSI in 2005 and 2006, respectively. Five QTL regions were detected in both years, including QTL on chromosomes 1A, 2A, 2B, and 3B. These same regions were commonly associated with QTL for flag leaf length, width, and visual wax content, but not with days to flowering. Pleiotropic trade-offs between the maintenance of kernel number versus increasing single kernel weight under heat stress were present at some QTL regions. The results of this study validate the use of the main spike for detection of QTL for heat tolerance and identify genomic regions associated with improved heat tolerance that can be targeted for future studies.  相似文献   
128.
ObjectiveTo determine the effects of ketamine-diazepam and ketamine-acepromazine combinations on intraocular pressure (IOP) in rabbits.Study designRandomized clinical trial.AnimalsSixteen adult New Zealand white rabbits approximately one year old, weighing 2.3 ± 0.2 kg were used in this study.MethodsThe animals were randomly divided into two groups of eight each (KA and KD). The pre-treatment IOPs were recorded in both groups (T0). All rabbits in group KA received intramuscular ketamine-acepromazine (ketamine 30 mg kg?1+ acepromazine 0.5 mg kg?1). Ketamine-diazepam (ketamine 30 mg kg?1 + diazepam 1 mg kg?1) was administered intramuscularly in members of group KD. The IOP values were measured at 5 (T5), 15 (T15), and 20 (T20) minutes after drug administration in both treatment groups.ResultsSignificant increases in IOP values were observed in both treatment groups at T5, T15, and T20 in comparison to the baseline values. In group KA the mean ± SD IOP at T5, T15, and T20 were 37 ± 13 (p < 0.001), 35 ± 4 (p < 0.001) and 34 ± 4 mmHg (p < 0.001). The post-treatment mean ± sd values in group KD were 23 ± 8 (p = 0.002), 23 ± 5 (p < 0.001) and 23 ± 6 mmHg (p = 0.001) at 5, 15, and 20 minutes respectively.Conclusion and clinical relevanceBoth ketamine-diazepam and ketamine-acepromazine combinations increased IOP after intramuscular administration in rabbits.  相似文献   
129.
Harovinton, a variety of tofu type soybean, and 11 derived null soybean genotypes lacking specific glycinin (11S) and beta-conglycinin (7S) protein subunits were investigated to determine whether changes in protein composition affected the protein recovery in soymilk and its soluble fractions after various centrifugation steps. As both heating and homogenization have a marked effect on the increase in protein solubility, the changes occurring during these processing steps were studied for each soybean genotype. Harovinton and 11S-null genotypes showed significantly higher protein yields than the other genotypes evaluated. Subunits of group I (A(1), A(2)) of glycinin had a negative impact on protein solubility in all treatments, but this effect was the greatest in unheated soymilk samples. Samples containing a high beta-conglycinin to glycinin ratio showed an effect of heating on the solubility of the protein, as beta-conglycinin subunits aggregate with heating. The presence of the alpha' subunit of beta-conglycinin aids in the recovery of protein in the supernatant prepared from lines containing group I (A(1,4) A(2)) glycinin. The results of this study will help determine which specific protein composition will confer an increased stability in soymilk and soymilk-derived products.  相似文献   
130.
The 16S r RNA gene of 49 streptococci of serological group B isolated from various origins was amplified by polymerase chain reaction (PCR) and subsequently digested with the restriction enzymes Rsa I and Msp I. The restriction profiles of all group B streptococci appeared to be identical indicating no intraspecies sequence variations of this gene. A fragment of the gene of two group B-streptococcal reference strains, including the hypervariable V2 region, could be amplified by PCR and sequenced. The sequence appeared to be identical and allowed the design of species-specific oligonucleotide primers. The primer pair used produced an amplicon with a size of 1250 bp and correctly identified all 49 group B-streptococci investigated but none of the control strains of various species and serogroups. This primer could be used in a multiplex PCR and allowed a rapid identification of bacteria of this species.  相似文献   
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