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11.
Cryoprotectant is the crucial factor in the cryopreservation process. In general, there are two types of cryoprotectant, permeating and non‐permeating cryoprotectants. Dimethyl sulfoxide (DMSO) and egg yolk are common permeating and non‐permeating cryoprotectants respectively. Hence, the objective of the present study was to determine the best proportion of DMSO and egg yolk for the cryopreservation of Rasbora tawarensis sperm. A completely randomized experimental design was used in this study which involves two types of cryoprotectant and their combination at different concentrations, namely 5% DMSO, 5% egg yolk, 5% DMSO + 5% egg yolk and 2.5% DMSO + 2.5% egg yolk. Every treatment was conducted in three replicates. Combination of 5% DMSO + 5% egg yolk gave the best results cryoprotectant treatment had significant effects on sperm motility, fertilization and hatching rate of the R. tawarensis eggs (p < .05). It is concluded that the best proportion of cryoprotectants for sperm cryopreservation in this species is 5% DMSO + 5% egg yolk.  相似文献   
12.
Low survival at early stage is the bottleneck in seahorse aquaculture, particularly in the feeding aspect since newborn seahorses must feed immediately upon birth to sustain themselves. Seahorses are visual predator, therefore preferred live feed such as zooplankton. In aquaculture, the most common live feed used is Artemia. In this study, two experiments were conducted to determine the effect of different Artemia enrichment on the growth and survival of newborn Hippocampus barbouri. In the first experiment, six treatments using Artemia enriched with Culture Selco Plus? (SELCO), thyroxine (T4), potassium iodide (KI), cod liver oil (CLO), cod liver oil in combination with thyroxine (CLO + T4) and potassium iodide (CLO+KI) were fed to newborn H. barbouri. Newly hatched Artemia were used as control. At the end of first experiment, treatments using CLO + T4 produced juvenile H. barbouri with the best (p < .05) wet weight (0.142 ± 0.000 g), while juvenile in treatment CLO+KI recorded the highest (p < .05) standard length (3.947 ± 0.014 cm). Subsequently, a second experiment was carried out using the two best enrichment (CLO + T4 and CLO + KI) from the first experiment, but given at different frequency (daily, twice a week, once a week, once in 2 weeks). Daily enrichment using both CLO + T4 and CLO + KI showed no significant (p > .05) difference in growth performance and survival of juvenile of H. barbouri. Interestingly, juvenile fed CLO + T4 enriched Artemia at frequency of twice a week also has no significant difference (p > .05) in survival and growth performance (except for final standard length) when compared with treatment CLO + T4 at daily frequency.  相似文献   
13.
The efficacy of antimicrobial treatment of cotton fabrics depends on various parameters of the coating process, such as the chemical nature and concentration of the antimicrobial agent, the composition of the crosslinking formulation, and the curing temperature. The inclusion complex of triclosan with β-cyclodextrin (βCD) was synthesized and characterized by FTIR, XRD, NMR, Raman, SEM, and TGA. The minimum inhibitory concentration and minimum bactericidal concentration of the complex against Klebsiella pneumoniae and Staphylococcus aureus were compared to those of its precursor. A multifactorial study included an evaluation of the effects of triclosan complexation with β-cyclodextrin, a comparison between the glyoxal and tetracarboxylic acid as crosslinkers, an investigation of the effect of crosslinker and catalyst concentrations, and a comparison of curing at 120°C and 180°C. The cotton was characterized by FTIR-ATR, the micrographs of treated samples were obtained by SEM and the weight add-on was calculated. The bactericidal properties were determined according to AATCC-147. The correlation between the coating process parameters and the antimicrobial efficacy was determined. The optimal combination leading to the highest weight add-on and the antimicrobial coating that was most durable to multiple detergent washes at an elevated temperature was the use of complexed triclosan grafted onto the cotton in the presence of tetracarboxylic acid, followed by curing at 180°C. The curing temperatures were 120°C (P=0.002) and 180°C (P=0.008), catalysts were 1 % and 2 % aluminium sulfate and sodium hypophosphite (P<0.001), and the crosslinkers were 5 % and 10 % glyoxal and butanetetracarboxylic acid (P<0.001); these parameters significantly enhanced the antimicrobial properties of the treated fabrics. The study showed that βCD did not have antimicrobial activity, while the βCD/triclosan-treated textile exhibited potential antimicrobial properties. Overall, the bactericidal activity of fabrics can be enhanced by using βCD/triclosan with 10 % butanetetracarboxylic acid as a cross-linker and 5 % sodium hypophosphite as a catalyst at a curing temperature of 180°C.  相似文献   
14.
It is most important to determine areas with recreation potential that can permit sustainable use of forest resources and also meet recreational uses. Under the method described in this study, using the Geographic Information System (GIS), a spatial suitability model for recreational use was combined with a recreational priority perceptual suitability model that depends on principal component analysis (PCA) and is based on the perceptions of both recreational users and experts. Using principal component analysis, five priority components explaining 69.371% of the total variance were identified out of 12 perceptual suitability components. These components are scenic beauty, accessibility, the surface of the landscape, tree type, and forest stand condition. The recreation terrain suitability value of an area with recreational potential was assessed with the assistance of these five priority components. This enabled us to generate a recreation terrain suitability value equation and a recreation terrain suitability value scale for a potential recreation area. This applicability of this approach was demonstrated in the identification of potential recreation areas in Trabzon, Turkey.  相似文献   
15.
Phytoremediation using vetiver grass (Vetiveria zizanioides) has been regarded as an effective technique for removing contaminants in polluted water. This study was conducted to assess the removal efficiency of heavy metals (Cu, Fe, Mn, Pb, Zn) using vetiver grass (VG) at different root lengths and densities and to determine metals uptake rate by plant parts (root and shoot) between treatments (low and high concentration). Removal efficiency for heavy metals in water by VG is ranked in the order of Fe>Pb>Cu>Mn>Zn. Results showed that VG was effective in removing all the heavy metals, but removals greatly depend on root length, plant density and metal concentration. Longer root length and higher density showed greater removals of heavy metals due to increased surface area for metal absorption by plant roots. Results also demonstrated significant difference of heavy metals uptake in plant parts at different concentrations indicating that root has high tolerance towards elevated concentration of heavy metals. However, the effects were less significant in plant shoot suggesting that metals uptake were generally higher in root than in shoot. The findings have shown potential of VG in phytoremediation for heavy metals removal in water thus providing significant implication for treatment of metal-contaminated water.  相似文献   
16.
17.
Brassica oleracea L. includes various types of important vegetables that show extremely diverse phenotypes. To elucidate the genetic diversity and relationships among commercial cultivars derived by different companies throughout the world, we characterized the diversity and genetic structure of 91 commercial B. oleracea cultivars belonging to six varietal groups, including cabbage, broccoli, cauliflower, kohlrabi, kale and kai-lan. We used 69 polymorphic microsatellite markers showing a total of 359 alleles with an average number of 5.20 alleles per locus. Polymorphism information content (PIC) values ranged from 0.06 to 0.73, with an average of 0.40. Among the six varietal groups, kohlrabi cultivars exhibited the highest heterozygosity level, whereas kale cultivars showed the lowest. Based on genetic similarity values, an UPGMA clustering dendrogram and a two-dimensional scale diagram (PCoA) were generated to analyze genetic diversity. The cultivars were clearly separated into six different clusters with a tendency to cluster into varietal groups. Model-based structure analysis revealed six genetic groups, in which cabbage cultivars were divided into two subgroups that were differentiated by their head shape, whereas cauliflower and kai-lan cultivars clustered together into a single group. Furthermore, we identified 18 SSR markers showing 27 unique alleles specific to only one cultivar that can be used to discriminate 22 cultivars from the others. Our phylogenetic and population structure analysis presents new insights into the genetic structure and relationships among 91 B. oleracea cultivars and provides valuable information for breeding of B. oleracea species. In addition, we demonstrate the utility of SSR markers as a powerful tool for discriminating between the cultivars. The SSR markers described herein will also be helpful for Distinctness, Uniformity and Stability (DUS) test of new cultivars.  相似文献   
18.
采用多级采样的方法研究了孟加拉国农村耕作区内棕榈树的传统利用模式和当地的管理经验。农民管理棕榈主要为获取树液产品,生产以糖为主的次生品。树液可直接用作饮料,也可加工成糖蜜或酒精饮料。7块不同地块为棕榈提供生长环境,20.40%的棕榈种植在果园内。尽管中等级的农民拥有多数棕榈(33%),但是主要管理棕榈的是没有土地的农民,他们靠棕榈维持生计。这些农民将自己的智慧应用到棕榈管理当中,从种植到开孔取树液再到产品加工。如果能更科学地管理棕榈,加上农民的智慧,棕榈业将会对当地经济发展起到重要作用,也会丰富当地生物多样性。  相似文献   
19.
为探究单翼迷宫式滴灌带坡度、进水压力和铺设长度对灌水均匀度的影响,以3种单翼迷宫式滴灌带为研究对象,以灌水均匀度作为评价指标,采用UL9(34)均匀正交设计试验,比较了3种不同流量的单翼迷宫滴灌带在进水压力、铺设长度和坡度作用下的灌水均匀度的变化规律.经直观分析、方差分析和多重比较进行综合评价,再由SPSS和PPR对试...  相似文献   
20.
This study was conducted to examine the compatibility between the Sarawak Forest Ordinance and Bidayuh Native Customary Laws in Sarawak and to gather the community members’ opinions on the compatibility of these laws. This study was carried out using two research methods, viz. a literature review and a survey among the Bidayuh community in Bau, Sarawak. The documents reviewed were the Forest Ordinance Chapter 126 (1958) and the Adat Bidayuh Order, 1994. There are several notable differences between the two laws in terms of, forest ownership, losing of rights to forest or inheritance, and the management of forest. A list of statements with six interval scales was presented and a majority of Bidayuh community members neither disagreed nor agreed with the statement, (1) Forest Ordinance respects the Bumiputera people’s rights (37.5 %; SD = 1.259) and (2) Forest Ordinance protects the Bumiputera people’s rights (37.5 %; SD = 1.281). The community members are also not sure about the consistency between these two laws (28.1 %; SD = 1.182). These results indicated the need for the State to respect the natives’ rights toward the forest land and its resources, recognize the Bidayuh Native Customary Laws and for the native people to learn about the constitutional provisions. Further studies are needed because the knowledge of Native Customary Law itself cannot guarantee the natives’ future in terms of economic, social and environmental aspects and there is also a need to review the current laws to achieve the objective to protect and preserve the natives’ rights.  相似文献   
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