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101.

Lack of control options for cool-season broadleaf weeds is a major deterrent to autumn-sown chickpea. Weed control and chickpea tolerance to PRE (pre-emergence) and POST (post-emergence) application of isoxaflutole and oxyflurofen, PRE metribuzin, POST pyridate, and flumetsulam were investigated at three locations, including Kermanshah, Kurdistan, and Hamedan provinces during 2017–2018. Untreated and weed-free checks were added for comparison. Pyridate and PRE oxyflurofen 125?g ai ha?1 caused the minor visual crop injury according to EWRS score (1–1.8), while the highest crop injury occurred with metribuzin (EWRS score 3.5–8.5) in whole locations. The most effective herbicides for weed reduction were pyridate (70–75%), PRE oxyfluorfen (69–76%), and POST oxyfluorfen (65–73%) at Kermanshah, PRE oxyfluorfen at 125 and 175?g ai ha?1 (70–78%), POST oxyfluorfen (70–76%) and pyridate (70–78%) at Kurdistan, PRE oxyfluorfen at 125 and 175?g ai ha?1 (88–96%), metribuzin (91–100%) and Pyridate (80–97%) at Hamedan. Pyridate and PRE oxyfluorfen at 125?g ai ha?1 resulted in the highest chickpea grain yield at the three locations. In general, PRE oxyfluorfen (125?g ai ha?1) was similar to pyridate in terms of efficacy in weed control and grain yield enhancement.

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102.
103.
There are several possible methods by which amine groups can be grafted on the surface of activated carbon (AC) to improve their capacity for CO2 adsorption. Ethylenediamine and diethylenetriamine were selected as amino compounds for anchoring on the surface of an oxidized AC. Oxidation of AC was carried out by concentrated nitric acid. For each amino compound, two “in-solvent” and “solvent-free” methods with a number of grafting times were studied. Nitrogen adsorption–desorption at 77 K and proximate and ultimate analysis were used to determine physical and chemical characteristics of the samples. Temperature-programmed (TP) CO2 adsorption test from 30°C to 120°C were performed to investigate the effect of modification on CO2 capture. The modification clearly had a negative effect on the textural characteristics of the samples, so the samples showed a less CO2 uptake at lower temperatures. However, the decrease of capture capacity with increasing temperature is to somewhat softer for amine-grafted samples, so that they have a capacity comparable to the parent sample or even more than that at elevated temperatures. This property may give the new adsorbents this opportunity to be used at flue gas temperature with a higher efficiency. CO2 capture capacity per unit surface area of all the amine-modified samples, however, was significantly improved, compared to the parent sample presenting a great influence of amino groups on the CO2 capture capacity. Moreover, the used amine compounds and grafting methods were compared in terms of adsorbent characteristics and CO2 uptake curves. Cyclic adsorption–desorption tests showed a satisfactory regeneration for the modified samples.  相似文献   
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105.
To improve the unnatural fade-pigmented skin of cultivated gilthead seabream, Sparus aurata, (if shown) the present study was initiated. The effects of either red bell-pepper (Capsicum annum) meal or carrot (Daucus carota) meal as a natural dietary carotenoid source, on growth and skin coloration of gilthead seabream growers were investigated. A basal/control diet (D1/CTR) was firstly formulated to contain 48% crude protein and 14% lipids, with no added-carotenoids. With this basal diet, two other test diets were similarly prepared and supplemented each with about 40mg/Kg total carotenoids from either red-pepper meal (D2) or carrot meal (D3). In a feeding trial, fish (mean IW, 94.86±0.3g) were fed one of the three diets (D1, D2, D3), in triplicates for each treatment, for 6 weeks in light-blue background PVC tanks supplied with natural seawater flow. Total carotenoids content of skin was determined spectrophotometerically at initiation and end of the experiment. Neither growth nor feed utilization were significantly (P<0.05) affected by the red pepper-added diet (D2) as compared to CTR diet. However, the carrot fed fish recorded the lowest and significant (P<0.05) weight gain (g/fish) and specific growth rate (SGR, %/d) among dietary treatments. There were no considerable (P>0.05) differences in major nutrients composition between fish fed the experimental diets. Total carotenoids content was significantly (P<0.05) increased, in the skin-opercle area, of fish fed the red pepper diet (D2) as compared to initial fish and to either carrot fed fish or CTR fish. Results have suggested that gilthead seabream can effectively bio-absorb natural carotenoid pigments (mainly capsansin and capsorbin) in red-pepper but not in carrot (mainly β-and α-carotene).  相似文献   
106.
Methemoglobin is oxidized hemoglobin that cannot bind to or dissociate from oxygen. In fish, it is most commonly caused by exposure to excess nitrites and can lead to abnormal swimming, buoyancy, or death. The methemoglobin concentration in mammals is determined by the balance of oxidizing agents versus reducing enzymes in erythrocytes. The objective of our studies was to characterize the enzymes that reduce methemoglobin in fish erythrocytes. Whole blood was collected from healthy rainbow trout. Methemoglobin was induced in vitro by NaNO2 exposure. Methemoglobin reduction in controls was compared to reduction in samples with added NADH, NADPH, or NADPH and methylene blue. Rainbow trout whole blood was also fractionated into cytosol, microsomal, and mitochondria/plasma membranes/nuclei fractions. The fractions were compared for NADH-dependent cytochrome b5 reductase (CB5R) activity and for nitrite induction of methemoglobin. The CB5R activity in rainbow trout erythrocytes was compared to the CB5R activity in equine, feline, and canine erythrocytes. Rainbow trout erythrocytes had significant NADPH methemoglobin reductase activity in the presence of methylene blue (P < 0.001). The CB5R activity was greatest (P < 0.001) in the plasma membrane/mitochondria/nuclei fraction. The CB5R activity in rainbow trout erythrocytes was not significantly different than canine or equine activity but was significantly lower than feline CB5R activity (P < 0.0001). Methemoglobin in rainbow trout erythrocytes can be reduced by CB5R or NADPH-dependent methemoglobin reductase. Unlike mammalian anuclear erythrocytes, which are dependent on soluble CB5R, the nucleated RBCs of rainbow trout use membrane-bound CB5R to reduce methemoglobin.  相似文献   
107.
Laser in dermatology   总被引:1,自引:0,他引:1  
The laser is a tool that will augment the surgical techniques available to the veterinarian. When using the laser compared with traditional surgery there are multiple procedures that can be performed with much greater ease, and some procedures that previously could not be performed. Specialty and academic practices have used lasers for photodynamic therapy, lithotripsy of urinary calculi, and percutaneous disk ablation. This article will focus on the lasers use in dermatology. It is essential that the surgeon learn the basics of laser physics, how the laser interacts with tissue and the safety issues one needs to consider during its use. On deciding to use the laser the surgical techniques chosen should always be based on considering the advantages and disadvantages the laser has to offer. The use of biomedical lasers is a "cutting edge" technique now available to our veterinary field.  相似文献   
108.
Electric arc furnace dust (EAFD) is a toxic waste which is mainly rich in iron oxide, zinc, and lead. Hydrometallurgical extraction of zinc from Jordanian EAFD in alkaline medium was investigated; NaOH, NaHCO3, and Na2CO3 were used as leaching agents. The pH values for the prepared solutions were 8.3, 8.2, and 12.55 for NaHCO3, Na2CO3, and NaOH, respectively. The effect of NaOH concentration (1, 3, 5, 7, and 9 M), contact time (5 min to 3 h), temperature (20, 40, and 60), and solid-to-liquid ratio (SLR; 20, 40, 80, and 120 mg/ml) on the leachability of zinc from EAFD were tested. The initial EAFD and the resulting leach residues were characterized using X-ray diffraction (XRD) and X-ray fluorescence (XRF). EAFD contained 25.9% Zn, 18.0% Fe, and 3.2% Pb. A maximum zinc recovery of 92.9% was achieved using 6 M NaOH at 60 °C with solid loading of 20 g/L and 3 h leaching time. NaHCO3 and Na2CO3 were not efficient leaching agents for Zn extraction since the recoveries were only 2.6 and 4.5%, respectively. Zn and Pb were depleted in the residues with an E-factor of 0.5–0.6 and 0.1–0.25, respectively. Iron was enriched in the residues; the E-factor was around 2. The EAFD contained mainly zincite, franklinite, and magnetite. After 3 h leaching, only traces of zincite exist in the residues, while sylvite and halite were completely dissolved.  相似文献   
109.
Contagious yawning is triggered by others yawning, and it has previously been reported in humans, primates and several experimental and companion mammals. Whereas it might be a response to an innate releasing mechanism, contagious yawning is also considered to involve emotional contagion. Here, we demonstrate that sheep, the animal model of livestock animals, also experience contagious yawning. Twelve adult castrated Corriedale sheep were used in this study. Pairs of sheep were adjacently restrained with or without a wooden divider panel to shield them from viewing the other. Their behaviors were video‐recorded for 3 days in each condition. Sheep yawned 2.0 ± 1.1 and 1.2 ± 1.1 times/day/head in the unshielded and shielded conditions, respectively. Unshielded restrained sheep yawned within 1 min after the other one 11.1% of the time, while shielded pairs did not exhibit contagious yawning. Rumination was also highly synchronized under the unshielded condition. These data reveal that contagious yawning and behavioral synchronicity occur in ruminants like sheep, making them a suitable animal model to investigate contagious yawning and the underlying mechanism.  相似文献   
110.
We investigated the effects of silicon (Si) and the levels and sources of salinity on the growth and some physiological properties of wheat (Triticum aestivum cv. Chamran) in a sandy loam soil under greenhouse conditions. Treatments comprised four Si levels (8, 50, 100 and 150 mg kg?1 soil), four salinity levels (0.46, 4, 8 and 12 dS m?1) and two salinity sources (sodium chloride (NaCl) and four-salt combination). Salts combination included NaCl, sodium sulfate (Na2SO4), calcium chloride (CaCl2) and magnesium sulfate (MgSO4) at a molar ratio of 4:2:2:1. The experiment was arranged as a completely randomized design in a factorial manner, with three replications. Increasing salinity level resulted in a significant decrease in shoot dry weight, chlorophyll content and catalase (CAT) activity, and it caused a marked increase in proline and glycine betaine (GB) concentrations and superoxide dismutase (SOD) enzyme activity. The stimulating effect on GB accumulation and SOD activity was more intense in NaCl-treated plants. However, the source of salinity had no significant effect on shoot dry weight, chlorophyll and proline concentrations, and CAT activity. Si application enhanced all the above-mentioned parameters, except for proline. The suppressing effect of salinity on shoot dry weight, chlorophyll concentration and CAT activity was alleviated by Si supplementation. The stimulating effects of Si fertilization on shoot dry weight and chlorophyll concentration became more pronounced at higher salinity levels. It could be concluded that a decrease in soil osmotic potential, nutrient imbalance and increasing reactive oxygen species (ROS) in salt-treated plants caused growth suppression, while Si supply decreased the deleterious effects of excess salt on wheat growth. Consequently, it appears that when wheat plants are to be grown in salt-affected soils, it is highly recommended to supply them with adequate available silicon (Si).  相似文献   
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