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81.
Because quantitative field estimates of potato (Solarium tuberosum L.) yield losses attributable to ozone (O3) air pollution damage in California need to be assessed, the antioxidant compound N-[-2-(2-oxo-l-imidazolidiny l)ethyl]-N′-phenylurea (EDU or DPX-4891) was evaluated for suitability in estimating these yield losses and in differentiating O3-susceptible from O3-resistant cultivars. Differential susceptibility of two cultivars, ‘Centennial Russet’ (O3sensitive) and ‘White Rose’ (O3-resistant), to O3 was confirmed in greenhouse experiments. Five weekly 5-hour treatments with 25 parts per hundred million O3 reduced tuber yield of Centennial Russet by 32% but did not reduce the yield of White Rose. In the absence of O3 under greenhouse conditions, EDU had no observable effect on shoot dry weight, tuber number, or tuber yield of either cultivar, suggesting that EDU does not materially affect plant growth in the absence of O3 at the treatment levels used and under the conditions herein. In field experiments conducted at the University of California at Riverside (UCR) and in commercial fields of Kern County (KC), untreated Centennial Russet and White Rose plants produced total tuber yields of 174 and 512 q/ha, respectively at UCR and 268 and 498 q/ha, respectively, at KC. At UCR, EDU applied at the highest rate—17.8 kg/ha—increased marketable and total tuber yields of Centennial Russet by 208 and 188 q/ha, respectively, and increased specific gravity by 0.013. White Rose was not affected by EDU. Averaged over four KC experiments, EDU application at 8.9 kg/ha increased Centennial Russet marketable and total tuber yields by 40 (from 214) and 45 (from 268) q/ha, respectively, whereas White Rose was not affected and averaged 398 (marketable) and 491 (total) q/ha.  相似文献   
82.
The environmental behavior and fate of tributyltin (TBT) in the northern Ariake Sea, resulting from the use of TBT-containing antifouling paints on hulls of ships, pleasure crafts and docking facilities, was assessed by numerical simulations. First, a mathematical model was devised on the basis of a non-steady state equilibrium, one box multi-compartment model consisting of the surface micro-layer, the water column, the mud-layer, and the bottom sediment compartments. The movement of TBT among the four compartments was modeled by resuspension of bottom mud, deposition of suspended sediment, film penetration and water advection in each compartment. Furthermore, a one-dimensional diffusion equation was introduced into the bottom sediment compartment to calculate profile distribution of TBT. The reactivity of TBT considered within the compartments included biological degradation, adsorption to particulate matter and diffusion. Next, the optimal amount of past TBT loads, reflecting the recent observations of TBT concentration in the waters and sediments of the northern Ariake Sea, was searched by a simple genetic algorithm. The relative sensitivity of various model parameters were also determined to identify the more important parameters for estimating the environmental behavior and fate of TBT. Finally, the future status of TBT contamination of the northern Ariake Sea was predicted assuming the discontinued use of TBT-containing antifouling paints. Despite its simple model structure relative to hydraulics, it was concluded that this multi-compartment model adequately estimated the environmental behavior and fate of TBT.  相似文献   
83.
Journal of General Plant Pathology - Burkholderia is a genus of aerobic gram-negative bacteria belonging to the phylum Proteobacteria. B. gladioli causes rot symptoms in economically important...  相似文献   
84.
1. The histochemical properties and the collagen content and architecture of the iliotibialis lateralis (ITL) and puboischiofemoralis (PIF) muscles were assessed in Red Cornish x New Hampshire cockerels reared on a high nutrient plane for 80 d (H80d), or a low nutrient plane for 80 d (L80d) or 95 d (L95d). 2. Final live weights were 3410 g in H80d, 2810 g in L80d and 3467 g in L95d. Both ITL and PIF muscle weights were lowest in L80d and did not differ between H80d and L95d. 3. ITL muscle was composed of fast-twitch myofibres such as IIA (high reduced nicotinamide adenine dinucleotide dehydrogenase, NADH-DH activity), IIB (low NADH-DH activity) and IIC (intermediate NADH-DH activity). The high percentage of type IIB myofibres in H80d (76.6%) and L95d (76.2%) birds were reflected in low percentages of type IIC myofibres (12.2%) in H80d birds and type IIA myofibres (8.2%) in L95d birds. Percentages of IIA, IIB and IIC myofibres in L80d cockerels were 12.4, 69.8 and 17.6%, respectively. 4. The myofibres in PIF muscle were divided into two basic types, I and IIA, and a transitional form (I-tr) from IIA to I. In the caudal region, all myofibres in H80d and L95d cockerels were type I but in L80d cockerels 15% of myofibres were categorised as type I-tr. In the cranial region, the great majority (52 to 63%) of myofibres were type IIA. Type I myofibres occurred at a higher percentage in H80d (30.5%) than L95d (21.8%) and type I-tr in L95d (15.7%) than H80d (7.3%) and L80d (11.5%). 5. The total amount of collagen was higher in ITL than PIF muscle in every bird group. In both muscles the highest collagen content was in L95d cockerels but the content did not differ between H80d and L80d birds. The thickness of thick and thin perimysia increased with muscle size. The circular collagen fibre in the thick perimysium was larger in ITL (6.1 to 7.0 microm) than PIF (3.7 to 3.8 microm) muscle but did not differ among the bird groups. 6. From these results, it was concluded that feeding on a high nutritional plane promotes growth of the thigh muscles, with accompanying enlargement of the perimysial thickness, no increase in collagen content and various changes of histochemical properties.  相似文献   
85.
We established an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of bovine macrophage colony-stimulating factor (M-CSF) and used it to measure the serum M-CSF levels in bovine fetuses and calves. The average serum M-CSF level was 2.7+/-1.5 ng/ml in 39 calves under 100 days old, and 1.8+/-0.8 ng/ml in 15 cattle between 101 and 418 days old. Fetal sera samples (n = 6) prepared from cattle between 150 and 280 days of gestational age had a higher average level of M-CSF (8.8+/-1.4 ng/ml). Alteration in serum M-CSF levels in each individual calf was also measured. The serum levels of M-CSF in calves at 0-1 day after birth ranged from 0.52 to 7.3 ng/ml. During the period 113-125 days after birth, serum levels were around 1.4+/-0.39 ng/ml. Although serum M-CSF levels generally decreased as the age of calves advanced, differences among individuals, especially among newborn calves, were observed.  相似文献   
86.
This study aims to estimate the mitochondrial genetic diversity and structure of Japanese Polled and Kuchinoshima feral cattle, which are maintained in small populations. We determined the mitochondrial DMA (mtDNA) displacement loop (D‐loop) sequences for both cattle populations and analyzed these in conjunction with previously published data from Northeast Asian cattle populations. Our findings showed that Japanese native cattle have a predominant, Asian‐specific mtDNA haplogroup T4 with high frequencies (0.43–0.81). This excluded Kuchinoshima cattle (32 animals), which had only one mtDNA haplotype belonging to the haplogroup T3. Japanese Polled showed relatively lower mtDNA diversity in the average sequence divergence (0.0020) than other Wagyu breeds (0.0036–0.0047). Japanese Polled have been maintained in a limited area of Yamaguchi, and the population size is now less than 200. Therefore, low mtDNA diversity in the Japanese Polled could be explained by the decreasing population size in the last three decades. We found low mtDNA diversity in both Japanese Polled and Kuchinoshima cattle. The genetic information obtained in this study will be useful for maintaining these populations and for understanding the origin of Japanese native cattle.  相似文献   
87.
Changes in the modulus of elasticity (MOE), modulus of rupture (MOR), and stress relaxation in the radial direction of wood (hinoki:Chamaecyparis obtusa) moisture-conditioned by the adsorption process from a dry state and by the desorption process from a moisture content slightly below the fiber saturation point were investigated. The MOE and MOR of wood conditioned by the adsorption process showed significant increases during the later stages of conditioning when the moisture content scarcely changed. However, with the desorption process they did not increase as much during later stages of conditioning, though they increased during early stages of conditioning when the moisture content greatly decreased. The stress relaxation of wood decreased with an increase in the conditioning period with both the adsorption and desorption processes. These results suggest that wood in an unstable state, caused by the existing state of moisture differed from that in a true equilibrium state shows lower elasticity and strength and higher fluidity than wood in a true equilibrium state. Furthermore, the present study demonstrates that the unstable states of wood induced during the course of drying, desorption, and possibly adsorption of moisture are slowly modified as wood approaches a true equilibrium state.  相似文献   
88.
ABSTRACT:   Variations in trawl dimension, bottom contact, and catch with differing warp lengths during walleye pollock surveys conducted by the Fisheries Research Agency were examined. The ratio of warp length to fishing depth (scope ratio) was set at 2.5, 3.0 and 3.5 at depths of 110 m. At a 2.5 scope ratio, the net mouth shape and footgear contact fluctuated, as the trawl door did not contact the bottom. Footgear contact was complete when the scope ratio was 3.0 or more. Walleye pollock, sculpins and flatfishes were the main catch in all tows, and the catch increased with scope ratio. There was no difference in the length frequency of walleye pollock ( n  = 300) captured at 2.5 and 3.0 scope ratio. However, the length frequency at 3.5 was significantly different from that of other scope ratios. These results suggest that at a scope ratio of 3.0 or more, the trawl door will not leave the bottom at any depths. To compliment echo surveys for walleye pollock, a 3.0 scope ratio would be optimal, since the catch data for a 3.5 scope ratio was dissimilar from that of scope ratios.  相似文献   
89.
Previously, we cloned a putative osmosensing histidine kinase gene (BcOS1) and revealed that a single amino acid substitution, isoleucine to serine at codon 365, conferred dicarboximide resistance in field isolates of Botrytis cinerea. This point mutation (type I) occurred within the restriction enzyme TaqI site of the wild-type BcOS1 gene. Thus, a procedure was developed for detecting the type I mutation of the BcOS1 gene using a polymerase chain reaction (PCR) in combination with restriction fragment-length polymorphism (RFLP). Diagnosis by PCR-RFLP was conducted on the 105 isolates isolated from 26 fields in Japan. All dicarboximide-sensitive isolates (49 isolates) had the wild-type BcOS1 gene, and the 43 isolates with the type I mutation were resistant to dicarboximides without exception. These data indicate that dicarboximide-resistant isolates with type I mutation are widespread throughout Japan. However, other types of dicarboximide resistance were detected among isolates from Osaka; among the 24 resistant isolates from Osaka, 12 had the BcOS1 gene without the type I mutation. BcOS1 gene sequencing of these resistant isolates classified them into two groups, type II and type III. The type II isolates have three amino acid substitutions within BcOS1p (368Val to Phe, 369Gln to His, and 447Thr to Ser). The type III isolates have two amino acid substitutions within BcOS1p (369Gln to Pro and 373Asn to Ser). These amino acid changes are located on the amino acid repeat domain in BcOS1p. The three types of resistant isolates were all moderately resistant to dicarboximides without significant osmotic sensitivity, and their pathogenicity on cucumber leaves was also very similar to that of the wild-type isolate.  相似文献   
90.
Gonadotropin-inhibiting hormone (GnIH), observed in quail as a member of the RFamide neuropeptide family, suppresses luteinizing hormone (LH) secretion from the avian pituitary. Rats and cattle have an active gene of another member of the RFamide neuropeptide family, termed RFamide-related peptide-3 (RFRP-3), although bovine RFRP-3 is different from that of rats in both length and amino-acid sequence. A single injection of GnIH or RFRP-3 inhibited LH secretion in rodents, which continued for various periods. This study was conducted to evaluate the effects of bovine C-terminal octapeptide of RFRP-3 (RFRP-3-8) on LH secretion from cultured anterior pituitary (AP) cells of cattle, and the effects of RFRP-3-8 injections on pulsatile LH secretion in castrated male calves. The suppressive effect of RFRP-3-8 on LH secretion from AP cells was observed in the presence of gonadotropin-releasing hormone (GnRH), but not in the absence of GnRH in culture media. In another experiment collecting blood samples serially from castrated male calves with repeated intravenous injections of RFRP-3-8 (n = 6) or saline (n = 6), the RFRP-3-8 group showed suppressed LH pulse frequency during the injection period (P < 0.05); however, the RFRP-3-8 group showed no difference from the saline group in all measures of LH secretion in the postinjection period. In conclusion, our results suggested that RFRP-3-8 suppresses LH secretion from cultured AP cells, as well as LH pulse frequency in cattle.  相似文献   
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