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81.
Genetic Resources and Crop Evolution - Zea mays ssp. parviglumis is the progenitor of maize and assume to have tolerance against various biotic and abiotic stresses. It...  相似文献   
82.
Antibody production was studied in cattle infected with rinderpest vaccine virus. Vaccinated cattle produced both IgM and IgG serum antibodies. The IgG antibodies were mainly those of IgG2 subclass. No IgA antibody response was detected in vaccinated animals.  相似文献   
83.
This study estimated the monetary value of urban forests’ non-priced benefits to tourists. Data collected by a face-to-face self-administered survey of urban tourists in Savannah, Georgia, USA were used to estimate tourists’ willingness to pay (WTP) for urban forests by the contingent valuation method. Individual WTP was found higher among tourists with graduate school education. Results suggested that WTP for urban forests also increased significantly with income and destination loyalty of the tourists. Estimated mean and median WTP values were $11.25 (95% confidence interval: $7.34, $15.16) and $2.10 (95% confidence interval: $1.38, $2.82), respectively. Based on the estimated mean WTP, annual value of urban forests to tourists in Savanna in 2009 ranged from a minimum of $81 million to a maximum of $167 million with a 95% confidence interval. The annual value was $11.55 million (95% confidence interval: $7.59 million, $15.51 million) based on the estimated median WTP and assuming at least 50% of the tourists in Savannah would pay the median amount. As the mean was greatly influenced by extreme WTP values in the data, the annual value based on the median value was a more conservative estimate.  相似文献   
84.
Isolated pairs ofH. nigrorepletus did not show hastened mating behaviour like those in the crowd. The early mating points towards an expedited secretion of certain sex hormones responsible for inducing early mating under crowding stress.Insects in cages put permanently in open air appeared healthy and vigorous while those in cages in rooms appeared run down. It was found that oxygen consumption in insects of open air cages was 13.3 × 10–4 ml./sec/adult in average. But there was no significant difference between crowded and isolated insects regarding oxygen consumption.  相似文献   
85.
Response of neuroendocrines to a chemisterilant in Acheta domesticus L. InAcheta domesticus administration of hemel — a chemosterilant — introduced neurosecretory changes coupled with hampered growth of the oocytes in ovarioles. A reduction in the haemolymphal acid and alkaline phosphatases activity was observed. It indicated that hemel led to reduction in protein and nucleic acid synthesis.  相似文献   
86.
The methanol extract of stem barks of Alianthus excelsa was partitioned with chloroform. The chloroform extract showed fungistatic and fungicidal activity against Aspergillus niger, A. fumigatus, Penicillium frequentence, P. notatum and Botrytis cinerea.  相似文献   
87.
OBJECTIVE: To assess rates of initiation of breast-feeding and exclusive breast-feeding within 2 months after delivery and to determine the factors influencing exclusive breast-feeding. DESIGN: A health worker-administered questionnaire survey was carried out during the time period 1 August-30 September 2005. SETTING: Immunisation clinics of Pokhara, a submetropolitan city in western Nepal. SUBJECTS: Three hundred and eighty-five mothers who had delivered a child within the previous 2 months. RESULTS: The rates of initiation within 1 h and within 24 h of delivery were 72.7 and 84.4%, respectively. Within 2 months after delivery, exclusive breast-feeding was practised by 82.3% of the mothers. Breast milk/colostrum was given as the first feed to 332 (86.2%) babies but 17.2% of them were either given expressed breast milk or were put to the breast of another lactating mother. Pre-lacteal feeds were given to 14% of the babies. The common pre-lacteal feeds given were formula feeds (6.2%), sugar water (5.9%) and cow's milk (2.8%). Complementary feeds were introduced by 12.7% of the mothers. By logistic regression analysis, friends' feeding practices, type of delivery and baby's first feed were the factors influencing exclusive breast-feeding practice of the mothers. CONCLUSIONS: Despite the higher rates of initiation and exclusive breast-feeding, practices such as pre-lacteal feeds and premature introduction of complementary feeds are of great concern in this urban population. There is a need for promotion of good breast-feeding practices among expectant mothers and also the community, especially the families, taking into account the local traditions and customs.  相似文献   
88.
The mineral mobilisation in ground water due to rock water interaction largely depends on the localized subsurface geo-chemical environment. During this work, traces of uranium were measured by adsorptive stripping voltametry (AdSV) in groundwater having various level of dissolved minerals. Experimental solutions were prepared in the laboratory by spiking natural groundwater with standard solutions of major cations (Ca2+, Mg2+, K+), anions (Cl?1, F?1, and $ {\text{PO}}^{{3 - }}_{4} $ ), trace metal ions (Cu and Pb) and DOC (Dissolved Organic Carbon). The concentrations of these anions, cations and DOC in subsurface water changes due to changes in the geo-chemical environment at different locations. Experimental results show that major anions do not have any pronounced impact on the analysis of uranium. In the case of cations, only Cu2+ shows strong interferences. However addition of 2% Ethylene Diammine Tetra-acetic Acid (EDTA) solution in the ratio of 1:25 removes interference due to copper upto a concentration of <0.2 ppm. Interference with copper was also studied by varying the accumulation potential, pH and concentration of chloroanilic acid. Though no interferences were observed in ground water having dissolved organic carbon (DOC) in the range of 0.01–15 ppm, between 15–16 ppm of DOC, the ability to detect uranium by AdSV decreases sharply. Further, if DOC exceeded 16 ppm it was not possible to do the analysis of uranium by AdSV without destruction of DOC, as DOC is a surface active organic compound and accumulates on Hg electrode preferentially over uranium-chloroanilic complex.  相似文献   
89.
ABSTRACT Analyses of multiple field experiments indicated that the incidence and relative abundance of root-colonizing phlD+ Pseudomonas spp. were influenced by crop rotation, tillage, organic amendments, and chemical seed treatments in subtle but reproducible ways. In no-till corn plots, 2-year rotations with soybean resulted in plants with approximately twofold fewer phlD+ pseudomonads per gram of root, but 3-year rotations with oat and hay led to population increases of the same magnitude. Interestingly, tillage inverted these observed effects of cropping sequence in two consecutive growing seasons, indicating a complex but reproducible interaction between rotation and tillage on the rhizosphere abundance of 2,4-diacetlyphloroglucinol (DAPG) producers. Amending conventionally managed sweet corn plots with dairy manure compost improved plant health and also increased the incidence of root colonization when compared with nonamended plots. Soil pH was negatively correlated to rhizosphere abundance of phlD+ pseudomonads in no-till and nonamended soils, with the exception of the continuous corn treatments. Chemical seed treatments intended to control fungal pathogens and insect pests on corn also led to more abundant populations of phlD in different tilled soils. However, increased root disease severity generally was associated with elevated levels of root colonization by phlD+ pseudomonads in no-till plots. Interestingly, within a cropping sequence treatment, correlations between the relative abundance of phlD and crop stand or yield were generally positive on corn, and the strength of those correlations was greater in plots experiencing more root disease pressure. In contrast, such correlations were generally negative in soybean, a difference that may be partially explained by difference in application of N fertilizers and soil pH. Our findings indicate that farming practices can alter the relative abundance and incidence of phlD+ pseudomonads in the rhizosphere and that practices that reduce root disease severity (i.e., rotation, tillage, and chemical seed treatment) are not universally linked to increased root colonization by DAPG-producers.  相似文献   
90.
Dynamic modulation of ion channels by phosphorylation underlies neuronal plasticity. The Kv2.1 potassium channel is highly phosphorylated in resting mammalian neurons. Activity-dependent Kv2.1 dephosphorylation by calcineurin induces graded hyperpolarizing shifts in voltage-dependent activation, causing suppression of neuronal excitability. Mass spectrometry-SILAC (stable isotope labeling with amino acids in cell culture) identified 16 Kv2.1 phosphorylation sites, of which 7 were dephosphorylated by calcineurin. Mutation of individual calcineurin-regulated sites to alanine produced incremental shifts mimicking dephosphorylation, whereas mutation to aspartate yielded equivalent resistance to calcineurin. Mutations at multiple sites were additive, showing that variable phosphorylation of Kv2.1 at a large number of sites allows graded activity-dependent regulation of channel gating and neuronal firing properties.  相似文献   
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