接种稀释水的空白对BOD5测定的影响

从接种液种类、空白ＢＯＤ５大小、接种液最佳添加范围等方面对ＢＯＤ５测定进行探讨，提出以接纳工业废水的河水作为最佳接种液，雨季时以土壤浸取液更适合。探讨了接种液空白值对ＢＯＤ５标液和工业废水的影响，结果表明，河水空白应控制在０．１－０．８ｍｇ／Ｌ土壤浸取液空白控制在０．０１－０．１０ｍｇ／Ｌ为宜。     

对BOD5分析方法中计算公式的探讨

对BOD5分析方法中计算公式存在的误差进行了分析，并提出了可消除计算误差的修正建议。     

Routine cytogenetic prenatal diagnosis using dynamic banding (RBG-GBG): A highly reproducible method for amniocytes,fetal cord blood,and chorionic villus investigations

Dynamic banding (RBG-GBG) using pulse 5-bromodeoxyuridine (5-BrdU) incorporation during part of the last S-phase before harvesting has been used in prenatal investigations. This method has already been routinely applied in 1344 cytogenetic investigations. GBG and RBG bandings produced almost identical patterns to classical G- and R-banding methods except for heterochromatic portions and some euchromatic segments. Nevertheless, these discordances may be somewhat helpful for cytogenetic diagnosis (i.e., X numerical abnormalities). The results showed particularly good contrast and staining; 5-BrdU incorporation did not prevent additional staining. Likewise, previous RBG or GBG disclosure allowed further chromosomal identification with C-banding or nucleolar organizer staining. Simplicity and reproducibility were very helpful in cases with a low mitotic index. 5-BrdU had no significant effect on in-vitro damage because only 0.31 per cent of cells were affected; so, we believe that dynamic banding should be used more extensively in cytogenetic investigations. Moreover, the staining and contrast qualities were very suitable for automatic methods of analysis now in use: i.e., metaphase finding and computer-assisted karyogram creation.     

Effect of the appetite stimulant cyproheptadine on deoxynivalenol ‐ induced reductions in feed consumption and weight gain in the mouse 1

Abstract

Deoxynivalenol (DON, vomitoxin), a Fusarium mycotoxin, is suspected of inducing its anorectic/feed refusal activity through a serotoninergic (5HT) mechanism, possible via 5HT₂‐receptors. In this study the efficiency of cyproheptadine (CYP), a serotonin antagonist and known appetite stimulant, to attenuate the adverse effect of DON was investigated in mice. CYP was administered in the feed for two days before animals began receiving the DON, which was also added to the feed. Both agents were administered concurrently thereafter for a 12‐day period. Dosing levels included various combinations of the two compounds, ranging from 0–16 ppm DON and 0–20 ppm CYP.

Results showed that CYP could effectively offset the reduction in feed intake caused by dietary DON, but only when dose levels were optimized (CYP appeared to have a narrow effective dose range, which was also dependent on the DON concentration). In fact, optimum CYP doses were able to enhance feed intake in DON‐fed mice above control levels, indicating that more than just a direct block of the toxin's effect was occurring. Conversely though, the effect of CYP on weight gain (WG) was ambiguous. At the lower CYP doses (≤ 5 ppm), alone or in combination with the lowest DON level tested (4 ppm), a modest positive effect was noted, but at the higher DON concentrations (≥ 8 ppm) the overall WG generally remained depressed, and tended to be reduced further by increasing doses of CYP.

These results provide additional support that serotoninergic mechanisms probably play a role in mediating DON‐induced reduction in feed intake. Where and how DON actually initiates its anorectic effect, however, has not been resolved.     

不同土地利用类型的地表特征参量的遥感反演研究——以猫跳河流域为例

利用2007年5月Lansat5 TM数据,运用单通道算法,基于全国遥感监测土地利用/覆盖分类体系,对贵州省猫跳河流域的地表特征参量进行了反演,得到不同土地利用类型下的典型地表特征参数值。在3种主要的土地利用类型中,林地的植被指数最高、地表温度最低,农田的植被指数最低而地表温度最高,草地介乎林地和农田之间。城镇建设用地主要表现为热岛效应,而水域则主要表现为地表温度（LST）和归一化植被指数（NDVI）的双低特征。进一步对二级土地利用类型的分析表明,由于结构、功能的不同,土地利用二级类在地表特征参量方面也表现出了有规律地变化。有助于深入认识不同土地利用类型的物理特征,可以丰富主要土地利用类型的影像分类的先验知识,有望将不同土地利用方式的生态环境效应研究推进一步     

Revealing life‐history traits by contrasting genetic estimations with predictions of effective population size

Effective population size, a central concept in conservation biology, is now routinely estimated from genetic surveys and can also be theoretically predicted from demographic, life‐history, and mating‐system data. By evaluating the consistency of theoretical predictions with empirically estimated effective size, insights can be gained regarding life‐history characteristics and the relative impact of different life‐history traits on genetic drift. These insights can be used to design and inform management strategies aimed at increasing effective population size. We demonstrated this approach by addressing the conservation of a reintroduced population of Asiatic wild ass (Equus hemionus). We estimated the variance effective size (N_ev) from genetic data () and formulated predictions for the impacts on N_ev of demography, polygyny, female variance in lifetime reproductive success (RS), and heritability of female RS. By contrasting the genetic estimation with theoretical predictions, we found that polygyny was the strongest factor affecting genetic drift because only when accounting for polygyny were predictions consistent with the genetically measured N_ev. The comparison of effective‐size estimation and predictions indicated that 10.6% of the males mated per generation when heritability of female RS was unaccounted for (polygyny responsible for 81% decrease in N_ev) and 19.5% mated when female RS was accounted for (polygyny responsible for 67% decrease in N_ev). Heritability of female RS also affected N_ev; (heritability responsible for 41% decrease in N_ev). The low effective size is of concern, and we suggest that management actions focus on factors identified as strongly affecting , namely, increasing the availability of artificial water sources to increase number of dominant males contributing to the gene pool. This approach, evaluating life‐history hypotheses in light of their impact on effective population size, and contrasting predictions with genetic measurements, is a general, applicable strategy that can be used to inform conservation practice.     

基于建筑信息模型的铁路工程安全管理体系研究

为解决铁路施工现行安全管理强度大、施工准备不足、部门间协作性与联系性较弱、信息滞后、施工保障不足等问题,充分考虑建筑信息模型的优势,结合建筑信息模型对铁路施工进行全生命周期安全管理。利用Revit对工程项目进行建模,结合三维模型对人员进行技术交底与安全教育,导入广联达BIM5D软件对工程项目的即时性管理。研究结果表明:该安全管理体系可以通过可视化设计、施工模拟在施工前充分准备,预先采取针对性安全措施;同时实现信息的全程实时共享,增强各部门之间的协调性和管理的及时性;结合建筑信息模型与云平台充分保障后期的运行与维护,达到对铁路工程进行高效、可行的全生命周期信息化安全管理的目的。     

对二乙氨基苯基亚甲基若丹宁固相萃取光度法测定银

研究了对二乙氨基苯基亚甲基若丹宁(DEABR)与银的显色反应,在柠檬酸—氢氧化钠缓冲介质(pH=2 5)中,乳化剂-OP存在下,DEABR与银反应生成2∶1稳定络合物,该络合物可用C18固相萃取小柱富集,小柱上富集的络合物用乙醇(含5%乙酸)洗脱后用光度法测定。在乙醇介质中λmax=545nm,ε=6.89×104L·mol-1·cm-1。银含量在0 01～2mg/L内符合比耳定律,方法用于环境水样中银含量的测定,结果令人满意。     

Refuse-derived fuel as a secondary energy in Taiwan—Using Hotelling space allocation model

Most Taiwanese farmers usually blend rice straws into the soil after harvest. However, rice straws possess great thermal energy, which can be used to produce refuse-derived fuel (RDF-5). As Taiwan faces energy shortage, the development benefits of the RDF-5 industry are tempting. This study employs the Hotelling model to design the locations and the optimal numbers of RDF-5 plants. From the technology and material supply point of view, turning waste rice straws into RDF-5 is feasible in Taiwan. Nevertheless, from the business operation perspective, even if the RDF-5 plant is willing to lower its profit rate, its selling price is still hard to compete with imported RDF-5. If the Taiwanese government decides to pursue RDF-5 as an alternative energy, they might need to take a step further to subsidize entrepreneurs or provide appropriate tax benefits. Otherwise, the RDF-5 industry is hard to survive in Taiwan.