Demographic transformation in Poland

The author presents a general review of the demographic transition in Poland from 1750 to the present day. Official data are used to describe the fluctuations in birth and death rates over this period.     

A gold key to initiate a new situation in family planning work]

Because of the popularization of a responsible agricultural production system, the livilihood of peasants has been improving greatly, while the demands and needs of the general public are also increasing at the same time. Still under the influence of the traditional belief of carrying on one's family line and emphasis on having male children, married people prefer to have more childre, and the birth rate is now rising again. In order to solve this new problem, we need to teach the peasants national policies on population, land utilization, and food supply. In order to initiate a new situation in family planning work, we need to control this "gold key" of ideological education and propaganda. The emphasis should be placed on ideological education for cadres at all levels as well as the general public in order that they may understand the Party's strategy. Education on the national strategy should be combined with material interests of the peasants, and reward and punishment in production should also be linked up with that of family planning. Social measures are needed to reduce economic burdens of the peasants, offer better treatment for single-child households, and provide adequate care for old and retired people. Family planning projects should be consolidated and improved. Scientific management, facilities and techniques for birth control, compensation for working personnel in family planning, and other practical problems deserve immediate attention and solution.     

Determination of recovery effort for a probabilistic recovery system under various inventory control policies

In this study we investigate the desired level of recovery under various inventory control policies when the success of recovery is probabilistic. All the used and returned items go into a recovery process that is modelled as a single stage operation. The recovery effort is represented by the expected time spent for it. The effect of increasing recovery effort on the success probability together with unit cost of the operation is included by assuming general forms of dependencies. Alternative to recovered items, demand is satisfied by brand-new items. Four inventory control policies that differ in timing of and information used in purchasing decision are proposed. The objective is to find the recovery level together with inventory control parameter that minimize the long-run average total cost. A numerical study covering a wide range of system parameters is carried out. Finally computational results are presented with their managerial implications.     

Assessing Risk‐Based Upper Limits of Melamine Migration from Food Containers

Melamine contamination of food has become a major food safety issue because of incidents of infant disease caused by exposure to this chemical. This study was aimed at establishing a safety limit in Taiwan for the degree of melamine migration from food containers. Health risk assessment was performed for three exposure groups (preschool children, individuals who dine out, and elderly residents of nursing homes). Selected values of tolerable daily intake (TDI) for melamine were used to calculate the reference migration concentration limit (RMCL) or reference specific migration limit (RSML) for melamine food containers. The only existing values of these limits for international standards today are 1.2 mg/L (0.2 mg/dm²) in China and 30 mg/L (5 mg/dm²) in the European Union. The factors used in the calculations included the specific surface area of food containers, daily food consumption rate, body weight, TDI, and the percentile of the population protected at a given migration concentration limit (MCL). The results indicate that children are indeed at higher risk of melamine exposure at toxic levels than are other groups and that the 95th percentile of MCL (specific surface area = 5) for children aged 1–6 years should be the RMCL (0.07 mg/dm²) for protecting the sensitive and general population.     

Is Tattooing a Risk Factor for Adolescents’ Criminal Behavior? Empirical Evidence from an Administrative Data Set of Juvenile Detainees in Taiwan

Juvenile crime affects not only the victims of the crime but also the delinquents’ future. How to prevent adolescent criminal behavior has become an important public policy issue. This study contributes to this interesting issue by examining the relationship between tattooing and adolescents’ criminal behavior. In particular, this study investigates whether or not having a tattoo/tattoos is connected to the incidence of various criminal activities, including: larceny, robbery, fraud, assault, drug use, and homicide. A unique sample of 973 juvenile detainees drawn from the administrative profiles in Taiwan and the coarsened exact matching method were utilized. Results show that compared to their nontattooed counterparts, tattooed juvenile detainees were significantly more likely to commit fraud, assault, drug abuse, and homicide by 3%, 13%, 9%, and 9%, respectively. In contrast, tattooing was not significantly associated with larceny or robbery. From a policy perspective, given the significant link between tattooing and criminal behavior, the presence of a tattoo in adolescents may serve as a valuable indicator regarding adolescents’ high probability of committing crimes.     

被神经性毒剂染毒的蛋白IgG中有机磷加合物的研究

本文对IgG与神经性毒剂的加合物进行了研究。用过量的神经性毒剂(沙林、梭曼、VX、环沙林)对IgG(人、大鼠IgG)进行体外染毒,用胰蛋白酶进行酶解,所得样品用Q Exactive LC-MS/MS方法进行分析鉴定,发现了IgG与神经性毒剂的加合物肽段。其中,从人的IgG中发现了4个被标记的肽段,从大鼠的IgG中发现了1个被标记的肽段,另外,还从肽段的二级谱图中发现了酪氨酸加合物的特征离子碎片。本文首次发现了被神经性毒剂标记的IgG肽段,进而说明IgG是鉴定神经性毒剂中毒的一类重要的标记蛋白。     

干渴的梯田:王金庄村水资源的分配与管理

河北省涉县旱作梯田系统是中国重要农业文化遗产。 其核心保护区域王金庄村位于太行山东麓,地形条件复杂,缺土少水、旱涝频发,但梯田系统因独特的人文智慧延续近八百年而不衰。 文章以水为切入点,阐释水资源短缺情形下百姓的生存逻辑与生计策略。 村庄作为一个系统对自然环境进行着补救性适应、抗风险适应与常态适应,这些文化适应性举措使旱作梯田的可持续发展得以实现,也展示出古老农耕智慧对于农业永续发展的重要意义。 因此,保护农业文化遗产不仅是对传统文化与社会系统的保护,更是对现代农业后果的生态补救,对农业与农村发展的现实反思,对可持续发展之路的探寻。     

水平井中砂泥岩互层的双侧向测井响应研究

摘要：针对砂泥岩互层的复杂测井环境，采用三维有限元数值模拟方法，计算了多层介质模型的水平井双侧向测井响应。结果表明，井眼半径、泥浆电阻率和围岩（砂岩、泥岩）的电阻率及侵入半径与电阻率对水平井双侧向测井响应都有不同程度的影响。在砂泥岩地层中，井眼尺寸越大，泥浆电阻率越高，对视电阻率的影响越严重；当目的层厚大于8 m 后，视电阻率受围岩（砂岩、泥岩）影响很小，基本上反映地层的真实电阻率，并且曲线变化规律大致相同，此时可近似为三层介质模型；对于低阻侵入，侵入越深，视电阻率越偏离真实地层电阻率。