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91.
In the present study, an assessment of land suitability potential for agriculture in the study area of IBB governorate, Republic of Yemen has been conducted through close examination of the indicators of land characteristics and qualities. The objective of this study is to evaluate the available land resource and produce the potential map of the study area. Remote sensing data help in mapping land resources, especially in mountainous areas where accessibility is limited. Satellite imagery data used for this study includes data from multi-temporal Landsat TM which dated June 2001. The parameters taken into consideration were 16 thematic maps i.e., slope, DEM, rainfall, soil, land use, land degradation as well as land characteristics maps. Satellite image of the study area has been classified for land use, land degradation and soil maps preparation, while topo sheet and ancillary data have been used for slope and DEM maps and soil properties determination. The land potential of the study area was categorized as very high, high, moderate, low and very low by adopting the logical criteria. These categories were arrived at by integrating the various layers with corresponding weights in a Geographical Information System (GIS). The study demonstrates that the study area can be categorized into spatially distributed agriculture potential zones based on the soil properties, terrain characteristics and analyzing present land use. This approach has the potential as a useful tool for guiding policy decision on sustainable land resource management.  相似文献   
92.
Maize yield is often limited by zinc (Zn) deficiency. The objectives of this study were to (i) evaluate maize yield response to Zn applied at four different rates, (ii) evaluate the yield response and agronomic efficiency of maize to the application of a complex fertilizer, MicroEssentials SZ (12N–40P–0K–10S–1Zn), compared to different rates of monoammonium phosphate (MAP) + ammonium sulfate (AS) + zinc sulfate (ZnSO4), and (iii) evaluate the association between tissue Zn concentration and soil-test Zn with the maize response to Zn fertilizer. Eleven experiments were carried out during the 2010, 2011, and 2012 growing seasons throughout eight states in the USA. Treatments consisted of four Zn rates of a physical blend of MAP + AS + ZnSO4 (0, 2.24, 4.48, 6.72, and 11.2 kg/ha Zn) and MicroEssentials SZ at a Zn rate of 2.24 kg/ha Zn. Nitrogen, phosphorus (P), and sulfur (S) rates were balanced across treatments (40 kg/ha P, 22 kg/ha S) and fertilizers were broadcast and incorporated immediately prior to planting. Treatment and location main effects were significant (P < 0.001) on corn yields, whereas the interaction treatment × location was not (P = 0.33). Maize responded positively to Zn fertilization; average yields across locations increased from 10,540 kg ha?1 without Zn to 11,530 kg ha?1 with 11.21 kg Zn ha?1 applied as a physical blend. The yield response and Zn agronomic efficiency of maize with the application of the complex fertilizer at a rate of 2.24 kg Zn ha?1 averaged 1004 kg ha?1 and 448 kg maize kg Zn?1, respectively, significantly higher (P < 0.1) than the yield response and Zn agronomic efficiency with the application of a physical blend with the same Zn rate, which averaged 293 kg ha?1 and 131 kg maize kg Zn?1, respectively. The Zn concentration in plant tissue of unfertilized plots varied greatly and was not related to the maize response to Zn fertilizer (r = 0.01; P = 0.98). With respect to soil Zn, a negative but nonsignificant relationship was found between maize response to Zn fertilizer and soil-test Zn (r = ?0.51; P = 0.16).  相似文献   
93.
Calcium (Ca) has been considered a key element in maintaining fruit quality and extending the storage period of several fruits. The main blueberry (interspecific hybrids of Vaccinium corymbosum x V. darrowii) market for the Southern Hemisphere production involves a long transport between harvest and consumption. Foliar Ca sprays during the pre-harvest constitutes a common practice for improving Ca concentration [Ca] in fruits and therefore in alleviating the loss of firmness, dehydration and rot decay during postharvest. In this study, two formulations of Ca; Ca-nitrate [Ca(NO3)2] and chelate Ca-oxide (Ca-gluconate; Ca-Glu) were sprayed four times during pre-harvest of blueberry cv. O’Neal. [Ca] in the fruits was followed after each application and fruit quality parameters were determined at harvest and during 28 days of cold storage. Both formulations were ineffective in increasing [Ca] in the berries (or leaves) after any of the four applications. In fruits, [Ca] decreased from 0.32% at 25 days after full bloom (DAFB) to 0.11% Ca at harvest time. Other minerals such as magnesium (Mg), potassium (K), or nitrogen (N) remained unaffected by the treatments. Data shows that foliar pre-harvest applications of Ca, regardless of formula, were ineffective at increasing [Ca] or improving the quality of the fruit.  相似文献   
94.
Five foods have been prepared from water extracts of immature corn (IC), immature corn-milk (CM) and immature corn-whole soybean (CS). The method of preparation followed either the common practice used for the immature corn drink or with certain modifications to increase yield. The protein quality of the three foods (IC, CM and CS) were evaluated and compared with that of casein. They had same digestibility (87–88%) but differed in protein quality. Two other foods, CS-1 and CS-2 were prepared using mechanical pressing of solubles. The corn-soy foods, CS-1 and CS-2, had almost the same digestibility as that of casein. An analysis of costs of materials indicated that the production of corn-soy food will be cheaper than the corn-milk food.  相似文献   
95.
Rat bocavirus (RBoV) and rodent bocavirus (RoBoV) have previously been detected in Rattus norvegicus; however, these viruses have not been reported in rodent populations in Malaysia. We investigated the presence of RBoV and RoBoV in archived rodent specimens. DNA barcoding of the rodent cytochrome c oxidase gene identified five different species: Rattus tanezumi R3 mitotype, Rattus tiomanicus, Rattus exulans, Rattus argentiventer, and Rattus tanezumi sensu stricto. Three spleens were positive for RBoV (1.84%; 3/163), but no RoBoV was detected. Phylogenetic analyzes of the partial non-structural protein 1 gene grouped Malaysian RBoV strains with RBoV strains from China. Further studies among rats from different geographical locations are warranted for this relatively new virus.  相似文献   
96.
In this study, the effects of corona plasma process on the dyeability and certain physical properties of woolen fabric were investigated. For this purpose, acid and 1.2 metal complex dyes, which are the most applicable dyes in the wool market were used. The patterns were examined to assess their dyeability, wettability, pilling resistance, alkali solubility, and strength values. The surface morphology and chemical structures were tested by X-ray photoelectron spectroscopy and alkali solubility analyses and also scanned by electron microscopy. Hydrophility indexes of the dyes that were used were determined. With the results of the experiments, their hydrophobic index is of vital importance, which is a factor for plasma efficiency on color depth. By using plasma treatment on woolen fabric, it is achievable to get a product with high hydrophility and pilling resistance values, dyeability, and less burdened dyeing bath.  相似文献   
97.
ObjectiveTo determine the minimal electrical threshold (MET) necessary to elicit muscle contraction of the pelvic limb or tail when an insulated needle is positioned outside (METout) and inside (METin) the lumbosacral epidural space in cats.Study designProspective, blinded study.AnimalsTwelve mixed-breed healthy adult cats, scheduled for a therapeutic procedure where lumbosacral epidural administration was indicated.MethodsUnder general anesthesia, an insulated needle was advanced through tissues of the lumbosacral interspace until its tip was thought to be just dorsal to the interarcuate ligament. An increasing electrical current (0.1 ms, 2 Hz) was applied through the stimulating needle in order to determine the MET necessary to obtain a muscle contraction of the pelvic limb or tail (METout), and then 0.05 mL kg?1 of iohexol was injected. The needle was further advanced until its tip was thought to be in the epidural space. The MET was determined again (METin) and 0.2 mL kg?1 of iohexol was injected. The cats were maintained in sternal position. Contrast medium spread was determined through lateral radiographic projections.ResultsThe radiographic study confirmed the correct needle placement dorsal to the interarcuate ligament in all cats. When the needle was placed ventrally to the interarcuate ligament, iohexol was injected epidurally in ten and intrathecally in two cats. The METout and METin was 1.76 ± 0.34 mA and 0.34 ± 0.07 mA, respectively (p < 0.0001).Conclusion and clinical relevanceNerve stimulation can be employed as a tool to determine penetration of the interarcuate ligament but not the piercing of the dura mater at the lumbosacral space in cats.  相似文献   
98.
Antioxidant activity of isocytisoside and extracts of Aquilegia vulgaris   总被引:1,自引:0,他引:1  
Two extracts (ethyl acetate and ethanol) and isocytisoside obtained from Aquilegia vulgaris were tested for their antioxidant and free radical scavenging activity in vitro. Inhibition both non-enzymatic (IC50: 150-219 microg/ml) and enzymatic (IC50: 23-60 microg/ml) microsomal lipid peroxidation was observed, the extracts being more active than isocytisoside. The substances tested appeared to be weak hydroxyl radical scavengers, showed very low TEAC values and moderate iron chelation ability. However, all preparations at the concentration 25 microg/ml inhibited superoxide anion formation at the range 47-68%. Despite of the lack of a potent free radical scavenging ability the substances tested demonstrated significant antioxidant activity. Relationship between this parameter and the content of phenolic groups was noticed.  相似文献   
99.
The effects of different tank background colours (green, black and white) on the growth performance and body coloration of juvenile river cafish, Pangasius hypophthalmus, were examined in this study. The experimental fish with an initial body weight (BW) 0.13 ± 0.05 g and total length (TL) 2.54 ± 0.37 cm were used, and groups of 15 fish per tank were randomly distributed. The experiment was conducted for 20 days as a triplicate for each treatment. Survival, growth in BW, body weight gain (BWG), total length (TL), total length gain (TLG), specific growth rate (SGR), condition factor, feed conversion ratio (FCR), swimming speed, body coloration and stress response were evaluated. River catfish reared in white and green tanks attained significantly higher BW, BWG, TL, TLG and SGR compared to the black tank. The white tank attained significantly better FCR compared to the black tank. River catfish showed the most active swimming behaviour in the green tank (5.49 ± 1.32 cm/s) while the least in the white tank (3.37 ± 0.93 cm/s). Body coloration of river catfish in the black tank showed almost pure black body coloration (75.59 ± 9.08), followed by the green tank (126.23 ± 17.46) and the white tank (148.19 ± 10.51). However, there was no significant difference in the stress level of river catfish reared in white and black tanks and insignificant to those reared in the green tank. The findings in this study showed that the white and green background colour tanks can be used for promoting growth of river catfish culture while the black background colour tank can enhance body coloration that is suitable as ornamental fish.  相似文献   
100.
Tuberculosis has become a major health problem globally. This is worsened by the emergence of resistant strains of Mycobacterium tuberculosis showing ability to evade the effectiveness of the current antimycobacterial therapies. Therefore, the efforts carried out to explore new entities from many sources, including marine, are critical. This review summarizes several marine-derived macrolides that show promising activity against M. tuberculosis. We also provide information regarding the biosynthetic processes of marine macrolides, including the challenges that are usually experienced in this process. As most of the studies reporting the antimycobacterial activities of the listed marine macrolides are based on in vitro studies, the future direction should consider expanding the trials to in vivo and clinical trials. In addition, in silico studies should also be explored for a quick screening on marine macrolides with potent activities against mycobacterial infection. To sum up, macrolides derived from marine organisms might become therapeutical options for tackling antimycobacterial resistance of M. tuberculosis.  相似文献   
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