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61.
LiF:Mg,Cu,Ag is a new dosimetry material that is similar to LiF:Mg,Cu,P in terms of dosimetric properties. The effect of the annealing temperature in the range of 200 to 350°C on the thermoluminescence (TL) sensitivity and the glow curve structure of this material at different concentrations of silver (Ag) was investigated. It has been demonstrated that the optimum values of the annealing temperature and the Ag concentration are 240°C and 0.1 mol% for better sensitivity, respectively. The TL intensity decreases at annealing temperatures lower than 240°C or higher than 240°C, reaching a minimum at 300°C and then again increases for various Ag concentrations. It was observed that the glow curve structure altered and the area under the low temperature peak as well as the area under the main dosimetric peak decreased with increasing annealing temperature. The position of the main dosimetric peak moved in the direction of higher temperatures, but at 320 and 350°C annealing temperatures, it shifted to lower temperatures. It was also observed that the TL sensitivity could partially be recovered by a combined annealing procedure.  相似文献   
62.
The predator Adalia bipunctata (Coleoptera: Coccinellidae) and the entomopathogenic fungus Lecanicillium muscarium, have been considered as potential biological control against aphids. While it can be difficult to achieve a high control level of Aphis fabae Scopoli (Hemiptera: Aphididae) using only a single beneficial agent, the research presented here aimed to determine the interaction between L. muscarium and A. bipunctata potential for control against A. fabae. Lecanicillium muscarium was found to cause about 30% mortality in A. bipunctata and with a reduction in feeding by about 15%. However, co-application of A. bipunctata and L. muscarium can cause an addititive effect in reducing aphid populations, resulting in about 90% reduction in aphid populations compared with control treatment. Thus, these two biocontrol agents have the potential to be complementary. This research study demonstrates that it is possible to combine A. bipunctata with L. muscarium to provide a sustainable method for management of A. fabae on broad bean cropping system and that field studies are required.  相似文献   
63.
Pink bollworm (Pectinophora gossypiella) is recognized as an important pest of cotton and can damage flowers and bolls of both Bt and non-Bt cultivars. Cry-1Ac in Bt cultivars is considered very effective in controlling lepidopterous larvae; therefore, the present study was carried out to investigate the impact of Cry1-Ac and the earliness index on the natural incidence of P. gossypiella at the Cotton Research Institute, Faisalabad. During 2015–2016, ten cultivars were used to determine the incidence of pink bollworm infestation. The experiment was repeated for 2 years. During the next year, Cry1-Ac and earliness traits of selected cultivars were also observed to determine their impact on pink bollworm. Correlation coefficient results regarding days to first flower (r value = 0.66) as well as the earliness index (r value = ? 0.62) exhibited a strong association with pink bollworm, but Cry1-Ac had a weak association (r value = ? 0.058) with pink bollworm. The coefficient of determination (R 2) explained that variability of pink bollworm due to Cry1-Ac, the earliness index, and days to first flower was 18.0, 38.5, and 43.5%, respectively. Principal component analysis results showed that the first two PCs expressed 87% of the total variability. Clusters made on the basis of the studied parameters revealed that clusters 2 and 3 comprised the cotton cultivars possessing earliness traits compared with cluster 1. Therefore, it can be concluded that the earliness index in cotton is an important component for the sustainable management of pink bollworm infestation, the need for which is endless to evade the pink bollworm problem in the era of climate change.  相似文献   
64.
We measured the PCO2 apneic threshold in preterm and term infants. We hypothesized that, compared with adult subjects, the PCO2 apneic threshold in neonates is very close to the eupneic PCO2, likely facilitating the appearance of periodic breathing and apnea. In contrast with adults, who need to be artificially hyperventilated to switch from regular to periodic breathing, neonates do this spontaneously. We therefore measured the apneic threshold as the average alveolar PCO2 (PaCO2) of the last three breaths of regular breathing preceding the first apnea of an epoch of periodic breathing. We also measured the PaCO2 of the first three breaths of regular breathing after the last apnea of the same periodic breathing epoch. In preterm infants, eupneic PaCO2 was 38.6 +/- 1.4 Torr, the preperiodic PaCO2 apneic threshold was 37.3 +/- 1.4 Torr, and the postperiodic PaCO2 was 37.2 +/- 1.4 Torr. In term infants, the eupneic PaCO2 was 39.7 +/- 1.1 Torr, the preperiodic PaCO2 apneic threshold was 38.7 +/- 1.0 Torr, and the postperiodic value was 37.9 +/- 1.2 Torr. This means that the PaCO2 apneic thresholds were 1.3 +/- 0.1 and 1.0 +/- 0.2 Torr below eupneic PaCO2 in preterm and term infants, respectively. The transition from eupneic PaCO2 to PaCO2 apneic threshold preceding periodic breathing was accompanied by a minor and nonsignificant increase in ventilation, primarily related to a slight increase in frequency. The findings suggest that neonates breathe very close to their PCO2 apneic threshold, the overall average eupneic PCO2 being only 1.15 +/- 0.2 Torr (0.95-1.79, 95% confidence interval) above the apneic threshold. This value is much lower than that reported for adult subjects (3.5 +/- 0.4 Torr). We speculate that this closeness of eupneic and apneic PCO2 thresholds confers great vulnerability to the respiratory control system in neonates, because minor oscillations in breathing may bring eupneic PCO2 below threshold, causing apnea.  相似文献   
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67.
Levels of Mo, As, Se, Fe, Cu, Zn, Ni, and Pb were determined in a vegetable commonly consumed in Pakistan. Samples were collected from three different sites (Ratokala, Phularwan, and Mailowal) supplied with three different water sources. Mo and Pb in water and Mo and As in C. sativum were higher than the suggested standards at the international level. Lower bioconcentration factor and pollution load index were seen at Site-I than at other sites. A positive association was found between the rhizosphere metals and those of the vegetable at all three sites. Enrichment factor at three sites ranged from 0.28 to 10.39. The highest value of daily intake of metals was found for Fe (0.245 mg/kg/day) and of the health risk index for As (70.41) at the wastewater inundated site. It is inferred that uptake of Mo, As, Cu, Ni, and Pb through C. sativum represents a high health danger to the individuals using this vegetable.  相似文献   
68.
Accumulation of different metals and metalloids was assessed in two vegetables radish (Raphanus sativus L.) and spinach (Spinacea oleracea L.) irrigated with domestic wastewater in the peri-urban areas of Khushab City, Pakistan. In general, the metal and metalloid concentrations in radish and spinach were higher at site-II treated with sewage water than those found at site-I treated with canal water. In case of radish at both sites the levels of metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, and Pb) were below the permissible level except those of Mn, Ni, Mo, Cd, and Pb. At both sites, the transfer factor ranged from 0.047–228.3 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: As > Fe > Ni > Zn > Cd > Mo > Se > Co > Pb > Mn > Cr > Cu, respectively. While in case of spinach at both sites, the concentrations of metals and metalloids in vegetable samples irrigated with canal and sewage water were observed below the permissible level except Mn, Ni, Zn, Mo, and Pb. At both sites, the transfer factor ranged from 0.038–245.4 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: Cd > Ni > Co > Se > Mn > Zn > Mo > Pb > Fe > Cr > As > Cu, respectively.  相似文献   
69.
Background: Pregnancy-related risk factors for necrotizing fasciitis are poorly understood. We investigated pregnancy-related characteristics associated with the long-term risk of developing necrotizing fasciitis, a rare life-threatening infectious disease. Methods: We analyzed a longitudinal cohort of 1,344,996 parous women in Quebec, Canada between 1989 and 2020. The main exposure measures included complications of pregnancy such as gestational diabetes, preterm delivery, metabolic disorder, and other maternal characteristics. We followed the women over time to identify future hospitalizations for necrotizing fasciitis up to three decades after delivery. We estimated adjusted hazard ratios (HR) and 95% confidence intervals (CI) for the association of pregnancy characteristics with risk of necrotizing fasciitis in time-varying Cox proportional hazards regression models. Results: A total of 420 women were hospitalized for necrotizing fasciitis during follow-up, including 83 (19.8%) with diabetes-related necrotizing fasciitis. The incidence of necrotizing fasciitis was elevated for women with gestational diabetes (2.9 per 100,000 person-years), preterm delivery (3.2 per 100,000 person-years), and metabolic disorders (5.4 per 100,000 person-years), compared with no pregnancy complication (1.1 per 100,000 person-years). Compared with no pregnancy complication, gestational diabetes was associated with 1.87 times the risk (95% CI 1.38-2.53), preterm delivery with 2.10 times the risk (95% CI 1.65-2.66), and metabolic disorder with 3.72 times the risk (95% CI 2.92-4.74) of developing necrotizing fasciitis over time. Pregnancy complications were more strongly associated with the risk of necrotizing fasciitis 5 years or more after delivery. Conclusions: Complications of pregnancy may be associated with the long-term risk of necrotizing fasciitis in women.  相似文献   
70.
Terminal heat stress causes irreversible damage to wheat crop productivity. It reduces the vegetative growth and flowering period that consequently declines the efficiency to capture available stem reserves (carbohydrates) in grains. Markers associated with thermotolerant traits ease in marker assisted selection (MAS) for crop improvement. It identifies the genomic regions associated with thermotolerant traits in wheat, but the scarcity of markers is the major hindrance in crop improvement. Therefore, 158 wheat genotypes were subjected to genotyping with 165 simple sequence repeat markers dispersed on three genomes (A, B and D). Allelic frequency and polymorphic information content values were highest on genome A (5.34 (14% greater than the lowest value at genome D) and 0.715 (3% greater than the lowest value at genome D)), chromosome 4 (5.40 (16% greater than the lowest value at chromosome 2) and 0.725 (5% greater than the lowest value at chromosome 6)) and marker xgwm44 (13.0 (84% greater than the lowest value at marker xbarc148) and 0.916 (46% greater than the lowest value at marker xbarc148)). Bayesian based population structure discriminated the wheat genotypes into seven groups based on genetic similarity indicating their ancestral origin and geographical ecotype. Linkage disequilibrium pattern had highest significant (P < 0.001) linked loci pairs 732 on genome A at r2 > 0.1 whereas, 58 on genome B at r2 > 0.5. Linkage disequilibrium decay (P < 0.01 and r2 > 0.1) had larger LD block (5–10 cM) on genome A. Highly significant MTAs (P < 0.000061) under heat stress conditions were identified for flag leaf area (xwmc336), spikelet per spike (xwmc553), grains per spike (cxfa2147, xwmc418 and xwmc121), biomass (xbarc7) and grain yield (xcfa2147 and xwmc671). The identified markers in this study could facilitate in MAS and gene pyramiding against heat stress in wheat.  相似文献   
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