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21.
Yong Kit Chin Nurhidayu Al‐saari Zarirah Zulperi Aslizah Mohd‐Aris Annas Salleh Santha Silvaraj Aslah Mohamad JingYie Lee Mohd Zamri-Saad Md Yasin Ina-Salwany 《Aquaculture Research》2020,51(1):389-399
Vibrio harveyi causes vibriosis in various marine aquaculture fish species, especially when they are young. The infection subsequently leads to significant economic losses for aquaculture farms. Vaccination is recommended to control this disease. This study describes the efficacy of a live attenuated V. harveyi strain MVh_vhs (LAVh) as a vaccine candidate in controlling infection by wild‐type V. harveyi (WTVh) in Lates calcarifer. A total of 240 fingerlings were divided into four groups. Group 1 was not vaccinated and was not challenged, Group 2 was vaccinated with a formalin‐killed V. harveyi (FKVh), Group 3 was vaccinated with the LAVh before challenge and Group 4 was not vaccinated and was challenged. Bath vaccination was employed for one hour before the LAVh distribution was determined in the fish mucus, gill, liver, gut, kidney and spleen. The gills, livers, kidneys and skins were also sampled for gene expression analysis. To challenge the fish, skin abrasion was conducted before the fish were challenged by immersion with WTVh. The results revealed an extensive distribution of the LAVh in the liver and kidneys of the fish in Group 3 for the first 12 hr, resulting in mild lesions compared with Group 1. Similarly, there were significantly (p < .05) higher expressions of the Chemokine ligand 4 and major histocompatibility complex I genes in the skin and liver of the fish in Group 3 in comparison with other groups. Vaccination with LAVh resulted in a significantly high rate of survival (68%) of the fingerlings after being challenged with WTVh. 相似文献
22.
The experimental results obtained from scratching a semicrystalline poly (ether ether ketone) surfaces, (PEEK), and its composites are presented in this paper. A semicrystalline PEEK and a carbon fiber oriented PEEK were scratched using conical indenters on a pendulum sclerometer. The carbon fiber oriented PEEK composites were scratched in the parallel, the orthogonal and the transverse direction to the fiber orientation. Subsequent deformations of the surfaces were assessed through subjective evaluation of the images obtained from a scanning electron microscope (SEM). The semicrystalline PEEK samples were found to be deformed by ductile ploughing and brittle deformation mechanism. In addition a fibrillation of the crystalline lamella of the polymer was also seen to be formed in case of severe brittle deformations. Fiber matrix debonding, matrix material debris formation, and fiber breakage were observed to be the dominant deformation mechanisms of the carbon fiber oriented composites. The scratch deformations of fiber oriented polymers were found to be highly dependent on fiber orientation angle relative to the scratching direction. 相似文献
23.
I. Lalarukh M. Arslan Ashraf M. Azeem M. Hussain M. Akbar M. Yasin Ashraf 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):501-510
Plant growth regulator, kinetin, is known to modulate the key physiological processes under abiotic stresses in different crops. However, kinetin-mediated response at different growth stages of crop plants is lagging behind. Therefore, a field experiment was conducted to appraise the potential role of exogenously applied kinetin in alleviating the effects of water scarcity on wheat. Three levels of kinetin (0, 75, and 150 mg/L) were used either as seed treatment or foliar spray at the vegetative or the post-anthesis stage. Water deficit markedly reduced shoot fresh mass, plant chlorophyll level, flag leaf photosynthesis, stomatal conductance, and transpiration rate. Degradation of chlorophyll a was greater in plants subjected to post-anthesis water-deficit conditions. However, plants growing under continuous water-deficit conditions had significantly lower concentration of chlorophyll b than those treated with water scarcity at the post-anthesis stage or receiving normal irrigation. Inhibited photosynthesis of wheat in response to post-anthesis water-deficit conditions was largely due to non-stomatal factors. In contrast, stomatal factors were the main constraints for photosynthesis in plants growing under continuous scarcity of water. Plants subjected to continuous water starvation had markedly lower grain yield than those subjected to water-deficit conditions at post-anthesis stage. Application of kinetin before seed sowing or at the post-anthesis stage significantly reduced the negative effects of drought on flag leaf chlorophyll and stomatal conductance. Lower level of kinetin (75 mg/L) was found to be more effective in mitigating the inhibitory effects of water shortage on photosynthesis and growth, and improved grain yield under water scarcity. 相似文献
24.
[目的]鉴定特色饮料"生命营养液"内源菌株CICC 10822并了解其生物学特性。[方法]采用传统微生物学分离培养方法对30℃条件下分离得到的新疆埃杜升"生命营养液"细菌CICC 10822进行多相分类鉴定。[结果]菌株CICC 10822接触酶反应阴性,硝酸盐还原阴性,淀粉水解阴性,精氨酸双水解酶阴性;能利用葡萄糖、果糖、核糖和半乳糖,不能利用麦芽糖、木糖、甘油、乳糖、甘露糖、山梨醇、纤维二糖、鼠李糖、阿拉伯糖,不液化明胶。利用基于形态学观察、生理生化特征分析及16S r DNA和phe S基因序列系统发育分析的微生物多相分类鉴定技术,将菌株CICC 10822鉴定为酸鱼乳杆菌(Lactobacillus acidipiscis)。[结论]试验结果为今后开展针对该菌的生物学功能研究奠定了基础。 相似文献
25.
M. Yasin Ashraf Mahnaz Roohi Zafar Iqbal M. Ashraf Münir Öztürk 《Communications in Soil Science and Plant Analysis》2016,47(4):405-413
Addition of cadmium, lead, and cadmium + lead (Cd, Pb, and Cd+Pb) to growth medium leads to a reduction in seed germination, length, fresh and dry biomass of shoots and roots, total chlorophyll, chlorophyll a, chlorophyll b, and soluble proteins in plants. This study was undertaken on two mungbean cultivars (MN-92 and MN-98). Application of these metals in the growth medium reduced the bioabsorption of calcium (Ca), magnesium (Mg), and potassium (K). Concentrations of all the metals were greater in the roots than in the shoots except for K, which was greater in the shoots. Mungbean cultivar NM-98 performed better than NM-92 in response to heavy-metal toxicity. Overall, the metal-induced physiobiochemical changes resulted in reduced growth of both mungbean cultivars. 相似文献
26.
Ramazan Özçelik Yasin Karatepe Nevzat Gürlevik Isabel Cañellas Felipe Crecente-Campo 《林业研究》2016,27(1):101-117
Estimating individual tree volume is one of the essential building blocks in forest growth and yield models.Ecologically based taper equations provide accurate volume predictions and allow classification by merchantable sizes, assisting in sustainable forest management.In the present study, ecoregion-based compatible volume systems for brutian pine and black pine in the three ecoregions of southern Turkey were developed. Several well-known taper functions were evaluated. A secondorder continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierarchical data, allowing the model to be applied to irregularly spaced and unbalanced data. The compatible segmented model of Fang et al.(For Sci 46:1–12, 2000) best described the experimental data. It is therefore recommended for estimating diameter at a specific height, height to a specific diameter, merchantable volume, and total volume for the three ecoregions and two species analyzed. The nonlinearextra sum of squares method indicated differences in ecoregion and tree-specific taper functions. A different taper function should therefore be used for each pine species and ecoregion in southern Turkey. Using ecoregionspecific taper equations allows making more robust estimations and, therefore, will enhance the accuracy of diameter at different heights and volume predictions. 相似文献
27.
Muhammad Asif Shehzad Muhammad Maqsood Fahim Nawaz Tasawer Abbas Sanaullah Yasin 《Journal of plant nutrition》2018,41(8):943-955
Terminal drought stress (drought at reproductive growth stage) has been considered a severe environmental threat under changing climatic scenarios and undoubtedly inhibits sunflower production. A field study was conducted to explore the potential role of foliar applied boron (B) (0, 15, 30, 45 mg L?1) at late growth periods of sunflower in alleviating the adversities of terminal drought stress (75, 64, 53 mm DI) grown from inflorescence emergence to maturity stages. The plant water relations such as leaf relative water content (RWC), water potential (Ψw), osmotic potential (Ψs), and turgor pressure (Ψp) were increased significantly with B foliar sprays while exposed to terminal drought stress. Foliar B application considerably improved the nitrogen and B concentrations in leaf and seed tissues, and also chlorophyll a and b pigments under terminal drought stress conditions. Drought-induced proline accumulation prevented the damages caused by drought stress, nevertheless, B foliar spray increased its contents. Compared to well-watered conditions, terminal drought stress substantially declined the growth performance in terms of reduced leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), and total dry matter (TDM) production; however, foliar B supply (30 mg L?1) might be helpful for improving drought tolerance in sunflower with reduced growth losses. 相似文献
28.
Muhammad Naeem Muhammad Shahbaz Naeem Rashid Ahmad Muhammad Zahid Ihsan Muhammad Yasin Ashraf Yasir Hussain 《Archives of Agronomy and Soil Science》2018,64(1):116-131
Water and nutrient restrictions are the factors that limiting growth of maize in arid/semi-arid climate. Calcium (Ca2+) uptake is affected severely under drought stress (DS). The objectives of this study were to investigate the effects of DS and foliar applied Ca2+ on growth, physiological, biochemical, yield and grain-nutrient content in two maize cultivars i.e. drought-tolerantDekalb-6525 and drought-sensitive Yousafwala-hybrid. The study comprised of two phases; firstly the best rate of Ca2+ (20, 40 and 60 mg L?1) was evaluated. Secondly, optimized rate of Ca2+ (40 mg L?1) was used to assess physio-biochemical and yield responses of maize under DS. The applied DS caused significant reduction in maize growth, water-status, photosynthesis and grain nutrient contents. Foliar Ca2+ markedly improved plant growth, water-potential (18%), turgor-potential (75%), photosynthesis (45%), stomatal-conductance (47%), transpiration rate (43%) and accumulation of total soluble sugars (20%) along with decline in H2O2 content (23%) in both cultivars under DS. Furthermore, optimized rate of Ca2+ improved maize grain yield and quality under water-deficit conditions. Cultivar Dekalb-6525 presented significant response to Ca2+ over Yousafwala-hybrid. Results of the study surmise that foliar supply of Ca2+ is an effective approach to make plants vigorous to thrive under limited-water supply. 相似文献
29.
Yasin Tuluce 《Pesticide biochemistry and physiology》2006,86(2):85-92
This study describes the subacute and subchronic effects of two plant growth regulators (PGRs) [abcisic acid (ABA) and gibberellic acid (GA3)] on serum marker enzymes [aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH), γ-glutamil transpeptidase (GGT)], antioxidant defense systems [reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT)] and lipid peroxidation level (Malondialdehyde = MDA) in various tissues of rats. Rats (Sprague-Dawley albino) were exposed to 75 ppm (parts per million) of ABA and GA3. Seventy-five parts per million of PGRs as drinking water was administered orally ad libitum for 25 and 50 days continuously. The PGRs treatments caused different effect on the serum marker enzymes, antioxidant defense systems and the content of MDA in comparison to those of control rats. Results show that ABA caused a significant decrease in serum LDH and CPK activity with both periods. Also, GA3 significantly decreased serum AST, CPK, and LDH activity with subacute and decreased serum ALT, CPK, LDH, and GGT treated with subchronic periods. The lipid peroxidation end product MDA significantly increased in the erythrocyte, liver, brain, and muscle of rats treated with both the period of GA3 without significantly change in the erythrocyte and muscle of rats treated with the subacute period of ABA. The GSH levels were significantly depleted in the erythrocyte and brain of rats treated with both the period of GA3 without any change in the erythrocyte, liver, brain, and muscle of rats treated with both the period of ABA. Also GSH levels in the muscle significantly depleted with the subchronic period of GA3. Antioxidant enzyme activities such as SOD significantly decreased in the erythrocyte, liver and brain tissues but increased in the muscle tissue of rats treated with both the periods of GA3. Meanwhile, SOD significantly decreased in liver and brain, and increased in muscle of rats treated with both the period of ABA. While CAT significantly decreased in the all tissues of rats treated with both the period of GA3, decreased in the liver and muscle of rats treated with both the periods of ABA too. On the other hand, the ancillary enzyme GPx and GR activity in the erythrocytes, liver, brain and muscle were either significantly depleted or not changed with two periods of PGRs. The drug metabolizing enzyme GST activity significantly decreased in the brain of rats treated with subacute period of PGRs but increased in the erythrocytes of rats treated with subacute period of GA3. As a conclusion, ABA and GA3 had significantly increased the activity of hepatic damage enzymes. Also the rats resisted to oxidative stress via antioxidant mechanism. However, the antioxidant mechanism could not prevent the increases in lipid peroxidation in rat’s tissues. These data, along with changes, suggest that PGRs produced substantial systemic organ toxicity in the erythrocyte, liver, brain, and muscle during the period of a 25-day subacute and 50-day subchronic exposure. 相似文献
30.
Recent studies have shown that propolis has on the oral cavity appreciable antibacterial, antifungal and antiviral actions, as well as anti-inflammatory, anaesthetic and cytostatic properties. In light of these studies, an assessment of the diffusion and permeation of caffeic acid phenetyl ester (CAPE) through porcine buccal mucosa was considered useful as a possible application in the stomatological field. To do so, a mucoadhesive topical gel was prepared to apply to the buccal mucosa. The gel was formulated in such a way as to improve the solubility of the propolis, conducting to an increase of the flux. The mucosal permeation of CAPE from the formulation was evaluated using Franz cells, with porcine buccal mucosa as septum between the formulation (donor compartment) and the receptor phase chamber. The diffusion through the membrane was determined by evaluating the amount of CAPE present in the receiving solution, the flux and the permeation coefficient (at the steady state) in the different formulations at set intervals. Qualitative and quantitative determinations were done by HPLC analysis. From the results, CAPE allowed a high permeability coefficient in comparison to the coefficient of other molecules, as expected from its physical-chemical structure. Moreover, the developed gel improved the CAPE flux approximately 35 times more with respect to an ethanol solution formulated at the same gel concentration. The developed gel was also tested in order to evaluate the mucoadhesive behaviour and comfort in vivo on 10 volunteers in a period of 8 h. The in vivo evaluation of mucoadhesive gel revealed adequate comfort and non-irritancy during the period of study and it was well accepted by the volunteers. 相似文献