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本文研究了木本植物的不同部位即叶片、枝条和树皮以及植物的生理指标如气孔阻力对大气S02、TSP和重金属污染的指示和监测作用,并用树木年轮指示大气污染的历史和程度。结果认为: 承德市大气污染自1703年城市化以来开始出现,但达到严重污染水平则出现在本世纪50年代以来尤其是最近10-20年城市化与工业化的加剧,主要污染物以S02为主,从避暑山庄修建前的<0.1μg m-3达到目前的30μg m-3,重金属污染Fe自1927-45大庙铁矿开采后出现,Mn、Ni、Pb等出现在工业化以来的最近40-50年中,上述污染物含量在木质部年轮中明显升高,如S增加了10倍以上,Pb增加了560% (P<0.00l)。 不同城市功能区树皮pH和气孔阻力不同,主要与大气中的S02和TSP有关,据此可监测大气S02和TSP污染。前者以榆树、加拿大杨、垂柳和国槐最佳,相关系数分别可达-0.8384 (P<0.0l),-0.7447、-0.6904和-0.6552 (P<0.05);后者则以白腊和旱柳下表皮最好,相关系数达0.9968和0.9951 (P<0.00l)。在扫描电镜下发现气孔受大气TSP影响出现不同程度的堵塞现象,主要有2种途径,小型颗粒物(<5μm)进入气孔腔,大型颗粒物(>30μm)可将气孔封盖。 植物不同器官部位污染物含量以树皮为最高,其次是枝条或叶,因而适宜的指示或监测部位是叶或枝条。主分量分析认为:承德市大气污染物以S为主,重金属Fe、Zn、Mn也有一定的贡献,Pb仅出现在繁忙道路区。不同季节污染物含量变化以休眠期最高,生长初期次之,生长旺盛期最低,如S和Pb分别从0.75 mg g-1和0.7 mg g-1上升到1.5 mg g-1和2.0 mg g-1(P<0.001)。植物不同季节污染物含量的变化反应了大气污染物季节变化特点,因而可以指示或监测大气污染尤其是S02污染。其中刺槐多部位复相关模型监测效果最佳,复相关系数可达0.987;某些植物单一部位的监测作用也较好,叶以珍珠梅最佳,相关系数为0.8695 (P<0.001),枝以油松、珍珠梅、垂柳为好(r≥0.8,P <0.001),树皮以刺槐为佳,r=0.8615 (P<0.0l)。植物不同部位的污染物含量还可用来评价大气环境质量,其中复合污染指数可以 评价总的大气环境质量,S污染指数和重金属污染指数可以评价S02、重金属和TSP污染,与直接利用污染物浓度法基本一致。油松不同部位对于大气S02的指示作用可表现为年轮对大气污染历史的指示或监测,针叶对现状S02污染的预测,并利用针叶对于S02的监测结果,绘制了大气S02污染分布图。 总之,本文利用古松年轮和现状城市植物的枝条、叶和树皮中的污染物含量以及树皮酸度等不同方面的指标,对承德市大气污染的历史和现状进行了指示与监测,即承德市大气污染从过去到现在均以S02为主,植物不同部位可以非常有效地进行大气S02污染的监测与评价,其中多部位的复相关模型预测效果极佳。另外,由植物监测而绘制的大气S02分布图,较准确地揭示了承德市大气S02现状分布规律。

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EXTRACT (SEE PDF FOR FULL ABSTRACT): Pollen analysis and 5 radiocarbon dates for a 687-cm core provide a detailed chronology of environmental change for San Joaquin Marsh at the head of Newport Bay, Orange County, California. Sediment deposition kept pace with sea level rise during the mid-Holocene, but after 4500 years BP, sea water regularly reached the coring site, and salt marsh was the local vegetation. Brief periods of dominance by fresh-water vegetation 3800, 2800, 2300 and after 560 years BP correlate global cooling events and (except the 3800-year BP event) with carbon-14 production anomalies. The coincidence of climate change and carbon-14 anomalies support a causal connection with solar variability, but regardless of the causal mechanism(s) the delta-carbon-14 curves provide a chronology for global, high-frequency climatic change comparable to that of Milankovitch cyclicity for longer time scales.

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An experiment was conducted to study the effect of different feeds on growth survival and production of African catfish (C. gariepinus) in six cemented tanks (3m² each) over a period of 120 days. Three different feeds namely Feed A (Saudi-Bangla fish feed, 33.43% protein), Feed B (formulated feed, 40.12% protein) and Feed C (chicken raw intestine, 59.58% protein) were applied to treatments I, II and III respectively. Each of the tanks was stocked with 24 fry with mean initial body weight of 2.56±0.06 g. Feeds were supplied to the fish ad-libitum daily in two instalments. Significantly highest weight gain was obtained in treatment III, however, survival rate was low compared to other treatments. The feed conversion ratio (FCR) values ranged from 2.52-6.4. Survival rate of fish varied between 83 and 96%. Treatment II yielded the highest (5000 kg/ha/120 days) production with the highest survival rate of fish. On the basis of survival rate and production, it is suggested that the formulated feed (Feed B) is suitable for the culture of C. gariepinus in cemented tanks.

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Marine by-products coming under the ancillary products group found many applications in pharmaceutical and industrial sectors. Although many of these products are fetching very high price at the export market, adequate statistics regarding their current production, marketing and utilisation is lacking. The present analysis deals with the production potential, level of exploitation, uses, export growth rate and potential for the future of some of these marine by-products. The analysis revealed that an estimated quantity of 205 t. of shells, 10 t. of gastropod operculum, 4,932 t. of shark liver oil and 4,384 t. of shark cartilage could be produced annually in India with the current landings. The production potential of chitin is estimated as 3,560 t. from shrimp shell wastes and 1,354 t. from crab shell wastes. The high unit value of different products clearly indicates the scope for their development by evolving appropriate utilisation and marketing strategies.

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本发明涉及大蹼铃蟾缓激肽及其制备方法和其基因,属于生物医学领域。其缓激肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由19个氨基酸组成的一种单链多肽,分子量2180,等电点11.7,多肽氨基酸全序列一级结构为:DLPKINRKGPRPPGFSPFR。制备方法是收集大蹼铃蟾皮肤分泌物,离心去除沉淀、冷冻干燥后,经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码大蹼铃蟾缓激肽基因核苷酸序列由cDNA由829个核苷酸组成,编码成熟大蹼铃蟾缓激肽为第140-196,224-280,308-364,392-448,476-532,560-616位6个核苷酸重复单元片断,从两栖类动物皮肤中得到的缓激肽基因作为基因工程制备缓激肽的应用。

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The objective was to study dynamic changes of ovaries in rhesus macaques stimulated by gonadotropins to identify an indicator for predicting ovarian response to stimulation. Twenty-one cycling monkeys were given 36 IU/d recombinant human follicle-stimulat

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The genetic structure of pikeperch (Sander lucioperca) and perch (Perca fluviatilis) populations was studied using microsatellite technique. A total of 207 specimens of adult pikeperch were collected from Aras dam (57 specimens), Anzali wetland (50 specimens), Talesh (50 specimens) and Chaboksar (50 specimens) coasts. Also a total of 158 specimens of adult perch were collected from Anzali (Abkenar (50 specimens)and Hendekhale(48 specimens)) and Amirkolaye(60 specimens) wetlands. About 2 g of each specimen's dorsal fin was removed, stored in 96% ethyl alcohol and transferred to the genetic laboratory of the International Sturgeon Research Institute. Genomic DNA was extracted using ammonium-acetate method. The quality and quantity of DNA was assessed using 1% agarose gel electrophoresis. Polymerase Chain Reaction (PCR) was conducted on the target DNA using 15 pairs of microsatellite primers. PCR products were electrophoresed on poly acryl amide gels (6%) that were stained that were stained using silver nitrate. DNA bands were analyzed with BioCapt software. Allele count and frequency, genetic diversity, expected and observed heterozygosity , allele number and the effective allele number, genetic similarity and genetic distance, Fst, Rst, Hardy Weinberg Equilibrium based on X2 and Analysis of Molecular Variance (AMOVA) at 10% confidence level was calculated using the Gene Alex software. Dendogram for genetic distances and identities were calculated using TFPGA program for any level of hierarchy. The results for P. fluviatilis showed that from 15 pair of primers that were examined 6 polymorphic and 7 monomorphic loci were produced, while 2 loci didn't produce any DNA bands. Mean allele number was 4.1±1.1 and mean observed and expected heterozygosity was 0.56±0.12 and 0.58±0.14 respectively. It was also seen that specimens from all regions were not in Hardy Weinberg Equilibrium in some of loci (P<0.001). Highest Fst (0.095) with Nm=2.37 was observed between Hendekhale and Amirkolaye and the lowest Fst (0.004) with Nm=59.31 was observed between Abkenar and Hendekhale. According to AMOVA Significant difference (P<0.05) was observed between recorded Rst in the studied regions in Anzali and Amirkolaye lagoons. In another words there are two distinct populations of this species in Anzali and Amirkolaye lagoons. The highest genetic distance (0.181) and lowest genetic resemblance (0.834) were observed between specimens from Hendekhale and Amirkolaye and the lowest genetic distance (0.099) and highest genetic 176 resemblance (0.981) were observed between specimens from Abkenar and Hendekhale. Based on the genetic dendogram tree derived by applying UPGMA algorithm, specimens from Anzali and Amirkolaye wetlands have the same ancestor. On the other hand there is no noticeable genetic distance between the specimens of these two regions. Also the results for S. lucioperca showed that from 15 pair of primers that were examined 6 polymorphic and 7 monomorphic loci were produced, while 2 loci didn't produce any DNA bands. Mean allele number was 3.0±0.6 and mean observed and expected heterozygosity was 0.52±0.21 and 0.50±0.14 respectively. It was also seen that specimens from all regions were not in Hardy Weinberg Equilibrium in some of loci (P<0.001). Highest Fst (0.093) with Nm=2.43 was observed between Aras dam and Anzali wetland and the lowest Fst (0.022) with Nm=11.27 was observed between Talesh and Chaboksar coasts. Significant differences (P<0.05) were observed between recorded Rst in the studied regions exept for Talesh and Chaboksar Coasts. In another words there are three distinct populations of this species in Caspian sea, Anzali wetland and Aras dam. Highest genetic distance (0.110) and lowest genetic resemblance (0.896) were observed between specimens from Aras dam and Anzali wetland and the lowest genetic distance (0.034) and highest genetic resemblance (0.966) were observed between specimens from Talesh and Chaboksar coasts. Based on the genetic dendogram tree derived by applying UPGMA algorithm, specimens from Talesh and Chaboksar coasts have the lowest genetic distance. On the other hand the main population of this species belongs to Anzali wetland. Phylogenetic relationship of these two species was inferred using mitochondrial cytochrome b gene sequencing. For this purpose 2 specimens of P. fluviatilis from Anzali wetland, 2 specimens of S. lucioperca from Aras dam and 2 specimens of S. lucioperca from Anzali wetland were sequenced and submitted in Gene Bank. These sequences were aligned with Clustal W. The phylogenic relationships were assessed with Mega 4. The results of evolutionary history studies of these species using Neighbor-Joining and Maximum Parsimony methods showed that the evolutionary origin of pikeperch in Aras Dam and Anzali wetland is common. On the other hand these two species had common ancestor in about 4 million years ago. Also different sequences of any region specimens are supposed as different haplotypes. 177 As a conclusion the results of this study showed that microsatellite and mtDNA sequencing methods respectively are effective in genetic structure and phylogenic studies of P. fluviatilis and S. lucioperca.

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采用引进的杜泊羊冷冻胚胎, 以云南当地绵羊为受体进行胚胎移植。同期发情处理了158 只受体 羊, 同期发情率为82191 %; 对102 只进行了胚胎移植, 实际移植率为77186 % , 3 个情期内移植妊娠率达 7415 %; 出生68 只, 产羔率达6617 %。分析表明, 胚胎发育阶段及级别、卵巢黄体情况、以及胚胎移植技术 熟练程度直接影响胚胎移植成功率; 此外, 受体羊的处理程序及移植后的饲养管理、移植时机的把握、移植季 节以及胚胎冷冻及解冻方法也会影响杜泊羊移植妊娠率, 进而影响产羔率。

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14周龄雄性昆明种小白鼠颌下腺摘除后第4周开始,附睾内精子数量呈显著减少趋势,第5和第6周的精子数分别为0.56±0.26×10~(7)和0.50±0.13×10~(7),与对照相比分别有显著差异( P<0.05)和非常显著差异( P<0.01)。摘除颌下腺手术后5周内小鼠的体重与对照相比无显著变化,但第6周的体重下降有明显的统计学差异( P<0.01)。

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External, prestressed carbon fiber reinforced polymer (CFRP) straps can be used to enhance the shear strength of existing reinforced concrete beams. In order to effectively design a strengthening system, a rational predictive theory is required. The current work investigates the ability of the modified compression field theory (MCFT) to predict the behavior of rectangular strap strengthened beams where the discrete CFRP strap forces are approximated as a uniform vertical stress. An unstrengthened control beam and two strengthened beams were tested to verify the predictions. The experimental results suggest that the MCFT could predict the general response of a strengthened beam with a uniform strap spacing < 0.9d. However, whereas the strengthened beams failed in shear, the MCFT predicted flexural failures. It is proposed that a different compression softening model or the inclusion of a crack width limit is required to reflect the onset of shear failures in the strengthened beams.

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Tracking methods have the potential to retrieve the spatial location of project related entities such as personnel and equipment at construction sites, which can facilitate several construction management tasks. Existing tracking methods are mainly based on Radio Frequency (RF) technologies and thus require manual deployment of tags. On construction sites with numerous entities, tags installation, maintenance and decommissioning become an issue since it increases the cost and time needed to implement these tracking methods. To address these limitations, this paper proposes an alternate 3D tracking method based on vision. It operates by tracking the designated object in 2D video frames and correlating the tracking results from multiple pre-calibrated views using epipolar geometry. The methodology presented in this paper has been implemented and tested on videos taken in controlled experimental conditions. Results are compared with the actual 3D positions to validate its performance.