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121.
The experimental results of orthogonal cutting of maple and the modeling of the cutting mechanics are presented. The tool cutting forces were measured for different feed rates. A set of equations relating the tangential and feed forces to the tool edge width and feed rate (chip thickness) to calculate the chip and edge cutting force coefficients was developed. Then the chip force and edge force coefficients were calculated from experimentally obtained cutting forces and were plotted in a polar-coordinate system with respect to the fiber orientation of the maple disk. The polar-coordinate presentation of the cutting force results and the calculated cutting force coefficients provides an excellent visual appreciation of the relation between the cutting forces and the wood fiber orientation. Chips were also collected from various sectors of the wood disk. This analysis further identified the effects of fiber orientation and cutting forces on the types of chip formed and hence the cutting mechanics involved. By applying the calculated cutting coefficients for each tool orientation (in respect to the grain) it is possible to predict the feed and tangential forces for any feed rates. There is good agreement between the predicted and measured cutting forces.  相似文献   
122.
The present study was conducted to isolate and characterize rhizobial strains from root nodules of cultivated legumes, i.e. chickpea, mungbean, pea and siratro. Preliminary characterization of these isolates was done on the basis of plant infectivity test, acetylene reduction assay, C-source utilization, phosphate solubilization, phytohormones and polysaccharide production. The plant infectivity test and acetylene reduction assay showed effective root nodule formation by all the isolates on their respective hosts, except for chickpea isolate Ca-18 that failed to infect its original host. All strains showed homology to a typical Rhizobium strain on the basis of growth pattern, C-source utilization and polysaccharide production. The strain Ca-18 was characterized by its phosphate solubilization and indole acetic acid (IAA) production. The genetic relationship of the six rhizobial strains was carried out by random amplified polymorphic DNA (RAPD) including a reference strain of Bradyrhizobium japonicum TAL-102. Analysis conducted with 60 primers discriminated between the strains of Rhizobium and Bradyrhizobium in two different clusters. One of the primers, OPB-5, yielded a unique RAPD pattern for the six strains and well discriminated the non-nodulating chickpea isolate Ca-18 from all the other nodulating rhizobial strains. Isolate Ca-18 showed the least homology of 15% and 18% with Rhizobium and Bradyrhizobium, respectively, and was probably not a (Brady)rhizobium strain. Partial 16S rRNA gene sequence analysis for MN-S, TAL-102 and Ca-18 strains showed 97% homology between MN-S and TAL-102 strains, supporting the view that they were strains of B. japonicum species. The non-infective isolate Ca-18 was 67% different from the other two strains and probably was an Agrobacterium strain.  相似文献   
123.
For the fuel type and water situation in the Middle East, the case is strong for the use of combined cycle technology for power generation and reverse osmosis for potable water production, where each are sited for their maximum economic benefit and interconnected by electric power transmission. Because of the fuel efficiency of Combined Cycle generation technology, its use of liquid/gas fuels and its low need for cooling water, it can be optimized for cost away from cities. Conversely, water desalination by reverse osmosis can be sited in optimal locations to take advantage of its modularity and to minimize water pipeline needs. Electric power transmission provides an inexpensive and flexible means to connect these two technologies. Together these technologies may offer an overall minimum cost approach, better than the combining of electric power and water desalination at one location, where power to water ratios must be fixed, independent of need, for optimum efficiency. The use of reverse osmosis with power generation has other, important ancillary benefits over using distillation and power combinations. These advantages include abatement of environmental pollution, delivery of potable water at reasonable drinking temperatures, lower total energy consumption, more efficient land use and less demanding operator skills.  相似文献   
124.
Acute pancreatitis (AP) is a well known complication of organophosphate (OP) poisoning and the true incidence is unknown; but, may be more common than clinically suspected. Previous studies suggest that Diphenhydramine (DPH) may be useful as an alternative or adjunctive therapy in OP poisoning. The aim of this experimental study was to investigate whether DPH could prevent or diminish pancreatic damage caused by OP poisoning as defined by histologic findings, and serum interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-α) levels. Twenty-four Sprague- Dawley rats were divided into equal three groups. Group 1 did not receive any agent during the experiment. Group 2 received 0.8 g/kg fenthion subcutaneously followed by 3 ml/kg normal saline intramuscularly, 30 min later. Group 3 received 0.8 g/kg fenthion subcutaneously, followed by 30 mg/kg DPH intramuscularly, 30 min later. Twenty-four hours later, pancreatic tissues were excised and blood samples were taken. After blood samples were taken by cardiac puncture, the animals were sacrificed. Treatment with DPH significantly decreased the serum TNF-α and increased the serum IL-10 levels. DPH significantly reduced pancreatic damage, including edema, inflammation, vacuolization and necrosis, as determined by pathologic scoring. The present study show that DPH decreased the severity of OP induced AP in rats. This effects may be related to a decrease of TNF-α level and increase of IL-10 level.  相似文献   
125.
Sunagoke moss Rachomitrium japonicum is a good potential for greening material. One of the primary determinants of Sunagoke moss growth is water availability. Too much or too little water can cause water stress in plants. Water stress in plants can be detected by imaging. This study is part of on-going research aimed at developing machine vision-based precision irrigation system in a closed bio-production system for cultured Sunagoke moss. The objective of this study is to propose nature-inspired feature selection techniques to find the most significant set of Textural Features (TFs) suitable for predicting water content of cultured Sunagoke moss. The proposed Feature Selection (FS) methods include Neural-Intelligent Water Drops (N-IWD), Neural-Simulated Annealing (N-SA), Neural-Genetic Algorithms (N-GAs) and Neural-Discrete Particle Swarm Optimization (N-DPSO). TFs consist of 120 features extracted from grey, RGB, HSV, HSL and Lab colour spaces using ten Haralick’s textural equations. Back-Propagation Neural Network (BPNN) model performance was tested successfully to describe the relationship between water content of Sunagoke moss and TFs. Red Colour Co-occurrence Matrix (CCM) TFs, L CCM TFs, grey CCM TFs, value(HSV) CCM TFs, green CCM TFs and lightness(HSL) CCM TFs are recommended as individual feature-subset to be used for predicting water content of Sunagoke moss using Artificial Neural Networks. However, FS methods improve the prediction performance. The results show a significant difference between model using FS and models using individual feature-subsets or without FS. Comparative analysis shows the superiority of Neural-Intelligent Water Drops (N-IWD) compared to the other FS methods, since it achieve better prediction performance. The best N-IWD’s fitness function converged with the lowest validation-set Root Mean Square Error (RMSE) of 1.07 × 10−2 when using 36 TFs.  相似文献   
126.
【目的】研究库尔勒香梨上可能诱导粗皮果形成的胁迫因子。【方法】基于分析库尔勒香梨粗皮果形成的基础上,对生长期的库尔勒香梨枝条采用50%程度地摘叶、外源喷施250 mmol/L的H2O22种人为逆境处理,在成熟期统计处理枝条上粗皮果率,对不同处理的果实进行组织切片染色,检测生理指标。【结果】库尔勒香梨成熟期对照组的粗皮果比率为18.10%,H2O2喷施和摘叶处理的粗皮果率分别为51.93%、29.52%;3组果实中果皮中的木质素含量分别为3.4%、4.9%、3.9%,果肉中的木质素含量分别为1.5%、1.7%、2.0%,2个处理组均提高了库尔勒香梨的粗皮果率以及果实中的木质素含量。H2O2喷施后外果皮的丙二醛(MDA)和活性氧(H2O2和O-2)含量显著增加,分别为对照的1.7和2.9倍。与之相应,库尔勒香梨果皮可溶性糖、淀粉等渗透调节物质含量也显著增加,分别为对照的1....  相似文献   
127.
The effects of dantrolene against fenthion-induced oxidative stress and muscle injury were investigated in rats. Malondialdehyde (MDA), reduced glutathione (GSH) ascorbic acid, retinol and β-carotene levels in blood were measured. Histopathological alterations and apoptosis in diaphragm were examined. Fenthion increased the level of MDA and decreased the levels of GSH in blood. Dantrolene administration prevented the rise in MDA levels and increased the GSH levels. There was no significant difference between β-carotene levels of experimental groups. However, fenthion toxicity led to decrease in ascorbic acid and retinol levels, dantrolene administration significantly prevented this decrease. Dantrolene significantly decreased the inflammation, edema and muscle necrosis or apoptosis in diaphragm muscle. Results of present study showed that toxicity of organophosphate compound fenthion increases the lipid peroxidation and depresses endogenous antioxidative systems, and leads to muscle injury in organism. Again, dantrolene administration prevents lipid peroxidation, augments antioxidant activity, and decreases muscle injury and apoptosis.  相似文献   
128.
The nutritive value of leaves of four varieties of cassava (MS 6, TMS 30555, Idileruwa and TMS 30572) were studied through analysis of their chemical components and degradability of their dry matter (DM) and crude protein (CP) in the rumen of sheep. Results of the chemical analyses showed that the leaves of the four varieties contained different proportions of organic matter which was significantly (P < 0.05) highest in TMS 30572 with value of 935 g/kg DM, while CP (gramme per kilogramme DM) was significantly highest in TMS 30555 (240), followed by MS 6 (235), TMS 30572 (208) and least in Idileruwa (177). Mean metabolisable energy (megajoules per kilogramme DM) was significantly (P < 0.05) highest in TMS 30572 (8.2) and similar with Idileruwa (8.0) but different from TMS 30555 and MS 6, respectively (7.8 and 7.6). The mineral contents (gramme per kilogramme DM) showed that leaves of MS 6 and Idileruwa had the highest concentrations of K (2.86) and a significantly lowest value (1.83) in TMS 30555. Also, the highest concentration of Ca and Fe (6.81 and 6.23) was recorded in MS 6. The highest Ca:P of 3.20 was obtained in TMS 30555. DM degradation characteristics and effective degradability varied significantly (P < 0.05) and were consistently highest in TMS 30572. The washing loss (a) ranged from 15.9% in MS 6 to 21.3% in TMS 30572. TMS 30572 tended to have higher (P = 0.546) insoluble but fermentable fraction (b) than all other varieties. Moreover, the potential degradability (a + b) tended to be higher (P = 0.041) in TMS 30572 (69.5%) followed by TMS 30555 (67.1%) and the lowest was in Idileruwa (42.7%). The highest effective degradability was recorded in TMS 30572 (63.9%) and the lowest in Idileruwa (40.7%). The degradation rate constants (c) of Idileruwa was significantly higher (P = 0.001) than those of MS6, TMS 30555 and TMS 30572. The results generally indicated that the leaves could be ranked for their potential feeding value as TMS 30572 (71.5%) > MS6 (65.8%) > Idileruwa (63.0%) > TMS 30555 (50.4%). It is therefore concluded from this study that leaves of TMS 30572 and MS 6 have good potential as feed resources for ruminant animals and could be used in ruminant feeding as protein source ingredient.  相似文献   
129.
A total of 304Rhizoctonia solani isolates and 60 binucleateRhizoctonia-like fungi were recovered from stems and tubers of infected potato plants over a 2-yr period in northeast Turkey.R. solani isolates were identified to 11 anastomosis groups (AGs): AG-1 (0.66%), AG-2-1 (5.6%), AG-2-2 (0.99%), AG-3 (83.9%), AG-5 (4.6%), AG-6 (0.66%), AG-8 (1.32%), AG-9 (0.33%), AG-10 (1.32%), AG-12 (0.33%), and AG-13 (0.33%). In the greenhouse tests, most of the AG-3 isolates were significantly more virulent than isolates belonging to other AGs on potato cv. Batum. Isolates of other anastomosis groups differed in their virulence. Results indicated that AG-3 is an important pathogen on potatoes grown in the study area. Five of 22 commercial and local potato cultivars evaluated for their reaction toR. solani AG-3 isolates (TP-2) under greenhouse conditions were highly resistant; the remaining cultivars exhibited different levels of susceptibility to the pathogen isolate. http://www.phytoparasitica.org posting July 14, 2005.  相似文献   
130.
Serdar  Ümit  Gülser  Coşkun  Akyüz  Burak  Balta  Ayşegül  Çil  Yusuf  Yilmaz Figen  Fatma 《Erwerbs-Obstbau》2022,64(2):237-244

The goal of this study was to determine the usability of nitrogen solution for hazelnut sucker management. This study was carried out from 2015 to 2016?at two hazelnut orchards; one established with the shrub (ocak) system in Atakum district and the other established with the multi-stemmed system in the Carsamba district, both in Samsun province. For sucker management, 21% ammonium sulphate (AS) and 26% calcium ammonium nitrate (CAN) fertilizer solutions were used. Doses of 0, 10, 15 and 20% of solutions for both fertilizers were tested. In the study, hazelnut suckers were removed by knife in July 2015 and March 2016. Nitrogen solution applications were started in September 2015 when suckers reached 20–30?cm length. In 2016 four applications were made from April to August. Fifteen days after the applications, the wilting ratio (starting from the tip) and newly emerged suckers per bush were determined. Nitrate, pH, and EC analyses were made with soil samples collected at the beginning of the experiment and compared to those taken 15 days after each application. As a result, a 10% dose of 21% ammonium sulphate fertilizer gave the best results for hazelnut sucker management. Nitrogen solution application should be started 1 to 1.5 months after removal of suckers by cutting with a knife. Suckers should be removed when they reach 15–20?cm length and before they are lignified. For effective sucker management, nitrogen solution application should be applied at least three times in a year.

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