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21.
对污泥茶渣等物料进行堆肥发酵,结果表明:不同物料配比堆肥第3d均进入高温(75℃)降解阶段,持续时间16~18 d.污泥含量40%~50%处理的全氮、速效氮含量高于污泥含量30%的处理;处理D全氮含量最高,达19.17 g·kg-,各处理全氮平均值大小顺序为D>E>C>B>A;处理E速效氮含量最高,为1171mg·kg...  相似文献   
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The effects of successive brassinosteroid analogue (BR) applications (0.1 mg l−1 of brassinosteroid analogue BB-16) were evaluated on commercial yellow passion fruit (Passiflora edulis f. flavicarpa) orchards in the first year of production. The treatments applied were: control, BR-1 (1 BR application shortly after the first flowers appeared), BR-2, BR-3, BR-4 and BR-5 (BR application in two, three, four and five consecutive weeks after the appearance of the first flowers, respectively). The fruits were collected for seven consecutive weeks (105 fruits treatment−1) and fruit mass, length and diameter, soluble solid contents; pulp mass and peel thickness were evaluated in the laboratory. Multivariate analysis was performed in order to determine whether there were differences among the treatments taking into account all the measurements made. BR-3 was the most promising treatment because it produced the highest number of fruits plant−1 (81.5) compared to the control (53.5) and the soluble solid content was 1 °Brix greater than the control. The BR-3 treatment resulted in a 65% increase in the estimated yield of the passion fruit plants, corresponding to 20 t ha−1 compared to the control yield of 12 t ha−1. The results showed that BB-16 sprayed during a period of reproductive development can increase the number of fruits per plant.  相似文献   
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OBJECTIVE: To evaluate the cardiorespiratory and behavioural effects of epidural xylazine (XYL) or clonidine (CLO) in horses. STUDY DESIGN: Blinded, randomized experimental study. ANIMALS: Twelve healthy Arabian yearling horses weighing 117-204 kg were randomly allocated into two groups: XYL (n = 6) and CLO (n = 6). METHODS: An epidural catheter was inserted and a facial arterial catheter was placed and the next day the horses were restrained in stocks. Baseline values for heart (HR) and respiratory (RR) rates, arterial pressure and behavioural responses were evaluated before (T0) and 10, 20, 30, 45, 60, 90 and 120 minutes after epidural injection (T10-T120). The horses received 0.2 mg kg(-1) of XYL or 5 microg kg(-1) CLO; adjusted to (3.4 + (body weight in kg x 0.013) mL with saline. Data were analysed by the Kolmogorov-Smirnov test, one-way anova with repeated measures, and one-way anova followed by a Student-Newman-Keuls test or Fisher's exact test, as necessary. Significance was set at p < or = 0.05. RESULTS: Sedation and ataxia were seen at T10, persisting until T120 in four and three horses, respectively, in XYL and all horses in CLO respectively. Two XYL and one CLO horses became recumbent at T45 and T25 respectively. Penile prolapse occurred in four of five males at T30 and T45, in the XYL and CLO groups, respectively, resolving by T120. Tail relaxation was present from T10 to T120 in all horses in XYL and in four horses in CLO. Head drop was observed from T20 to T60 and from T10 to T120 in XYL and CLO respectively. Respiratory rate decreased significantly only at T45 in the CLO group. Heart rate and arterial blood pressure remained stable. CONCLUSIONS AND CLINICAL RELEVANCE: Epidural CLO and XYL produce similar cardiorespiratory and behavioural changes but neither would be safe to use clinically at the doses used in this study.  相似文献   
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Optically pumped nuclear magnetic resonance (OPNMR) measurements were performed in two different electron-doped multiple quantum well samples near the fractional quantum Hall effect ground state nu = 13. Below 0.5 kelvin, the spectra provide evidence that spin-reversed charged excitations of the nu = 13 ground state are localized over the NMR time scale of about 40 microseconds. Furthermore, by varying NMR pulse parameters, the electron spin temperature (as measured by the Knight shift) could be driven above the lattice temperature, which shows that the value of the electron spin-lattice relaxation time tau1s is between 100 microseconds and 500 milliseconds at nu = 13.  相似文献   
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Fifty strains of Staphylococcus spp. isolated from bovine mastitis cases in several herds from different Argentinian provinces were screened for antimicrobial substances. Twelve strains exhibited a high antagonistic activity against the indicator strain (Corynebacterium fimi) and were chosen for further characterisation. The antimicrobial substances were sensitive to proteolytic enzymes suggesting that they might be bacteriocins (Bac). These strains were identified as S. aureus by the amplification of the femA gene. Plasmid profile analysis of these strains revealed the presence of at least one plasmid. Eleven strains carried a plasmid with a size similar to that of pRJ6 (8.0kb), which encodes aureocin A70, a bacteriocin produced by the Brazilian S. aureus strain A70 isolated from commercial milk. The other strain harboured a much larger plasmid. PCR experiments, using specific primers for amplification of the bacteriocin operon found in pRJ6, showed that all strains had the expected 525bp amplicon, suggesting that the bacteriocin produced may be related to aureocin A70. The genomic DNA of all Bac(+) strains was then analysed by pulsed-field gel electrophoresis (PFGE) in order to investigate clonal relationships amongst strains. Based on the results of PFGE experiments, 10 out of the 12 Bac(+) strains belonged to the same clone. The remaining two strains are possibly related to the prevalent clone. The aureocin A70 producer-strain belonged to a distinct clone.  相似文献   
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Boron (B) deficiency causes a wide array of symptoms, not only among species of palms, but also within a single species (i.e. Cocos nucifera). A better understanding of the effects of B deficiency in coconut will be important to try optimizing a rational fertilization management in coconut plants. Thus, modification of PSII photochemistry (using a group of fluorescence parameters, called the JIP- test, that quantify the stepwise flow of energy through Photosystem II) and gas-exchange in boron deficient green dwarf coconut plants were investigated. Our results suggest that a modification of PSII photochemistry (non-stomatic effects) and gas-exchange (stomatic effects) were induced by boron deficiency. Such modifications are manifested by (1) increase the ratio of total dissipation to the amount of active reaction centers (RCs) [dissipation (DI)/RC] and (2) leaf-to-air vapor pressure difference (VPDleaf-air). These modifications (on PSII photochemistry and gas-exchange) were caused by a decrease in energy absorbed per excited cross-section [absorption flux (ABS)/cross section of the sample (CS0)], density of active reaction centers (RC/CS), maximal trapping rate of an exciton that will lead to QA reduction measured over a cross- section of active and inactive RCs [trapping flux (TR)/CS0], electron transport per excited cross-section [electron transport flux (ET0)/CS)], area above curve (proportional to the pool size of the electron acceptors QA on the reducing side of PSII), photosynthesis (A), stomatal conductance (gs), transpiration (E), chlorophyll concentration (SPAD readings), growth parameters (root DW and height plant). Our results demonstrate that by analyzing fluorescence (JIP test parameters) derived from the polyphasic fluorescence transients measurements were able to estimate the functional changes of PSII in B deficient coconut plants. The results in this study suggest that fluorescence analysis (JIP test) and instantaneous measurements of gas-exchange can be useful tools in assessing the physiological effects of B deficiency in green dwarf coconut.  相似文献   
29.
This study evaluated the effect of in vitro digestion of flaxseed products on Folin-Ciocalteu reagent reducing substances (FCRRS), its antioxidant capacity and prevention of oxidative DNA damage in human monocyte cell line U937. Flaxseed protein isolate was obtained from defatted flaxseed meal and the protein hydrolysate with high antioxidant capacity was obtained from hydrolysis of the protein isolate with Alcalase in a two factor central composite rotatable design (pH 8.5 and enzyme: substrate 1:90, w/w). The FCRRS content and antioxidant capacity measured by FRAP and ORAC in aqueous and 70 % methanol extracts were the highest in protein hydrolysate, followed by protein isolate, while the defatted meal showed the lowest values. After in vitro gastrointestinal digestion, the FCRRS content of protein isolate and hydrolysate reached similar values, however the hydrolysate had the highest antioxidant capacity, measured by FRAP while the isolate had the highest ORAC values. The defatted meal showed the lowest capacity in all assays (p?<?0.05). The hydrolysate did not protect against DNA damage induced by H2O2 in U937 cells under the conditions of the present study. The results suggest that flaxseed protein isolate and hydrolysate are potential functional food ingredients with antioxidant capacity.  相似文献   
30.
In the present study, 188 coagulase-negative Staphylococcus (CNS) strains were isolated from bovine mastitis cases from 56 different Brazilian dairy herds, located in the Southeast region of the country, and were tested for antimicrobial substance production. Twelve CNS strains (6.4%) exhibited antagonistic activity against a Corynebacterium fimi indicator strain. Most antimicrobial substances were sensitive to proteolytic enzymes suggesting that they might be bacteriocins (Bac). Amongst the CNS producers, six were identified as S. epidermidis, two as S. simulans, two as S. saprophyticus, one as S. hominis and one as S. arlettae. Plasmid profile analysis of these strains revealed the presence of at least one plasmid. The Bac(+) strains presented either no or few antibiotic resistance phenotypes. Three strains were shown to produce a bacteriocin either identical or similar to aureocin A70, a bacteriocin previously isolated from an S. aureus strain isolated from food. The remaining Bac(+) strains produce antimicrobial peptides that seem to be distinct from the best characterised staphylococcal bacteriocins described so far. Some of them were able to inhibit Listeria monocytogenes, an important food-borne pathogen, and several strains of Streptococcus agalactiae associated with bovine mastitis, suggesting a potential use of these bacteriocins either in the prevention or in the treatment of streptococcal mastitis.  相似文献   
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