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991.
Responses of narrow‐leafed sweet lupins (Lupinus angustifolius L.) to foliar sprays of different sources of manganese (Mn) were compared in field experiments in three years at six sites in Western Australia. The relative effectiveness of manganese chelate (EDTA; 14% Mn) and manganese sulfate (25% Mn) applied as foliar sprays for alleviating Mn deficiency of lupins was assessed. Each source was sprayed at six levels of Mn (0, 0.125, 0.250, 0.50, 1.0, and 2 kg Mn/ha) when pods on the main stem were 2–3 cm long to define the relationship between seed and the amount of foliar Mn applied for lupins grown on Mn‐deficient soil. Manganese chelate, manganese sulfate, and the Mangasol sprays were equally effective. For all sources, 1.0 kg Mn/ha sprayed on the foliage was required to produce maximum seed yield and reduce split seed to an acceptable level (<4%). In all years, manganese sulfate banded with the seed produced similar seed yields as Mn sprayed on the foliage.  相似文献   
992.
The effects of crop residues alone (Cr+) or combined with inorganic fertilizer (FCr+) sewage sludge (SS) and humentos (H) on soil properties were studied in a five-season wheat–guar rotation. Incorporation of Cr+ and SS significantly decreased pH by 5–9%. Highest organic carbon (OC) was observed in SS plots, whereas Cr+ resulted in values threefold that of the control. The added effect of Cr+ (46%) combined with fertilizer on total nitrogen (TN) was greater than Cr+ by 28%. The fraction of total residue N mineralized was 71%, whereas net N mineralized in Cr+, SS, H and FCr+ plots at 0–20 and 20–40 cm depths were 39.8, 52.3, 11.4, 66.7 mg kg?1 and 21.2, 27.9, 8.2, 41.2 mg kg?1, respectively. Integrated application of Cr+ with fertilizer had a synergistic effect on P content (3.49–3.69 units), but soil levels has never exceeded 13 mg P kg ?1. Sole Cr+ significantly increased topsoil cation-exchange capacity (CEC) compared with the control treatment (9.39–21.59%). Application of SS, FCr+ and Cr+ significantly increased water-holding capacity and decreased bulk density by 9–15% and 8–9%, respectively, suggesting that such practice can restore the productivity of degraded soils and improve crop yields.  相似文献   
993.
A scoping literature review found evidence supporting the hypothesis that a population’s pollution status could help refine classification of emerging infectious disease (EID) hotspots. Systematic literature reviews and studies designed to specifically test the predictive value of pollutant status on EID risk are recommended.  相似文献   
994.
Feline chronic gingivitis/stomatitis (FCGS) is a painful inflammatory disease in cats. Extraction of teeth, including all premolars and molars, has been shown to be the therapy of choice in cats not responding sufficiently to home care (e.g. tooth brushing) and/or medical treatment (corticosteroids and/or antibiotics). In this study, we hypothesize that a cat food with an omega‐6 polyunsaturated fatty acid (ω6 PUFA) to ω3 PUFA ratio of 10:1 reduces inflammation of the FCGS and accelerates soft tissue wound healing of the gingiva after dental extractions, compared to a cat food with a ω6:ω3 PUFA ratio of 40:1. The cats were fed diets with chicken fat and fish oil as sources of fatty acids. In one diet, part of the fish oil was replaced by safflower oil, resulting in two diets with ω6:ω3 PUFA ratios of 10:1 and 40:1. This double‐blinded study in two groups of seven cats revealed that dietary fatty acids influence the composition of plasma cholesteryl esters and plasma levels of inflammatory cytokines. The diet with the 10:1 ratio lowered PGD2, PGE2 and LTB4 plasma levels significantly, compared to the diet with the 40:1 ratio (p = 0.05, p = 0.04, and p = 0.02 respectively). However, feeding diets with dietary ω6:ω3 PUFA ratios of 10:1 and 40:1, given to cats with FCGS for 4 weeks after extraction of all premolars and molars, did not alter the degree of inflammation or wound healing.  相似文献   
995.
A glasshouse study was undertaken to investigate the effects of the copper fungicide Kocide 101 and its residues in soil on the growth, nodulation and nitrogen fixation of beans (Phaseolus vulgaris L.). The soil used was a sandy clay loam classified as Typic Rhodustalf. The bean variety SUA 90 was used as test crop. The bean rhizobia strains CIAT 899, PV, and a local isolate were used. Kocide 101 applied at the recommended rate (equivalent to 1.7 mg kg‐1 soil) had no significant negative effects on the growth, nodulation or nitrogen fixation of bean plants. Higher levels of Kocide 101 significantly (P < 0.05) reduced plant growth, nodulation and nitrogen fixation. The bean plants inoculated with the “local isolate”; rhizobia had the highest dry matter weights, nodule numbers and nodule dry weights, and also had more N fixation. They were followed by those inoculated with the PV, strain and, lastly, those inoculated with CIAT 899. The growth and nodulation of bean plants were still curtailed by the Kocide 101 residues four months after the fungicide was first applied to the soil. Therefore, occurrence of high levels of Kocide 101 in soils can have long‐term effects on the performance of the bean‐rhizobia symbiosis.  相似文献   
996.
Imperfect detection associated with sampling gear presents challenges for wildlife inventory and monitoring efforts. We examined occupancy dynamics and habitat use of juvenile coho salmon, Oncorhynchus kisutch, in shallow lake environments over a summer and early fall season in the Knik River area of south central Alaska using models which control for and estimate sampling gear detection efficiency. In addition, we present statements for the probability that observed absences at a survey site or from a survey area (a collection of sites) are true absences given some amount of sampling effort and analysts' beliefs about site occupancy and sampling gear detection efficiency which can be used to guide inventory and monitoring efforts for juvenile salmon or other wildlife and plant species. Occupancy modelling results demonstrate that minnow traps were effective at sampling juvenile coho in shallow lake environments, with a mean probability of detection across the study period of 0.68 (i.e., probability of detecting the presence of juvenile coho given that they are present at a trap site; SE = 0.03). Juvenile coho salmon migrated into shallow water lakes in late summer and early fall, presumably to seek out overwinter habitat. N‐mixture modelling examination of habitat use demonstrated that once in shallow lake environments, juvenile coho were widely distributed across a range of microhabitats, with some evidence for preference for shallower depths and warmer water temperatures.  相似文献   
997.
998.
Circulating antibodies to larval Argas polonicus antigen detected in the blood of pigeons by means of ELISA reach their highest level 3-6 days post-tick attachment. During 6-8 days post infestation when most larvae detach from their host, there is an abrupt drop of the antibody level in blood followed by second peak at day 10-15. During the secondary and subsequent infestations the dynamics of the antibody production is analogous, but the maximum absorbance values found are higher with each following infestation. This is in direct correlation with the growth of immune resistance of hosts. The transfer of immunoglobulins of resistant pigeons produces in naive hosts a partial resistance in a statistically significant (P less than 0.01) reduction of the number of engorged larvae, in the shortening of larval feeding period and in the decrease of their mean weight after feeding. However this resistance was significantly (P less than 0.01) less expressed than in naturally resistant pigeons during secondary infestation. The protracted effect on the duration of premoulting period and the percentage of moulted larvae manifested in larvae after secondary infestation was not apparent in molecular weight of approximately 19, 21, 23, 27, 45 and 165 kilodaltons, were recognized by serum of resistant pigeons.  相似文献   
999.
In recent years, spotting of ray florets of gerbera flowers has become an important problem. This type of small necrotic lesions may occur before, but especially shortly after harvesting the flowers.Botrytis cinerea was easily isolated from such lesions. Inoculation withB. cinerea only gave typical necrotic lesions, when dry conidia were dusted on the flowers with a short period of high rh after inoculation. At 18–25 °C a high rh for at least 5 hours was necessary. Rotting of ray florets and receptacles byB. cinerea occurred when inoculated flowers were kept wet for a few days. Spots consist of one to several necrotic, usually epidermal cells. A single conidium could give rise to a necrotic lesion after germination. Germination of conidia and lesion formation occurred between 4 and 25 °C; at 30 °C, germination and lesion formation did not occur. Between 18 and 25 °C, many lesions became visible within 1 day after inoculation; at 4 °C it took 2 to 3 days before lesions could be seen. If kept dry, conidia ofB. cinerea remained ungerminated on ray florets of gerbera flowers and could be removed from the ray florets. Within 1 day at high rh, germination occurred and lesions were produced. Conidia ofB. cinerea, stored dry, were able to survive much longer than the lifetime of a gerbera flower. Even after storage at room temperature for up to 14 months, some conidia were able to germinate in vitro and on ray florets and induce the formation of lesions. Addition of gerbera pollen diffusate stimulated germination and lesion formation.  相似文献   
1000.
The word stability is ubiquitous in colloid science but means different things to different people. In a suspension concentrate it is possible to identify three different physical processes which may lead to instability in a particulate system, namely a change in particle size due to Ostwald ripening, particle aggregation and particle sedimentation. Although these processes may occur simultaneously they are here treated separately in order to promote understanding of the physical forces involved.  相似文献   
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