Lek mating system and its impact on male annihilation technique

Summary Simulation models were presented which describe the matings inside a lek. The size of the lek was assumed to follow a poisson distribution, the dominance factor of each of the males was drawn from a gamma distribution, and the mating probability for each male was determined by its mating effectiveness raised to female mating factor divided by the sum of all the mating effectivenesses raised to this power. The mating probatility for each male and the actual matings were determined by Monte Carlo simulation. Based on the simulation data, the effects of female mating factor and size of the lek on the frequency of actual matings accomplished by the males inside the lek were discussed. In the case of male annihilation, the mean number of effective matings per male in the lek, calculated from the frequency of actual matings weighted by the effective mating ratio, was used to evaluate the efficiency of male annihilation method.     

Models for mating disruption by means of pheromone for insect pest control

Models are presented to investigate the population dynamic behavior of a pest population with the release of pheromone for mating disruption. Three mechanisms of mating disruption are considered: (i) confusion of males, (ii) competition with female pheromone trails yielding false trail following, (iii) emigration of males prior to mating. In addition, several refinements to confusion are considered. Confusion and emigration of males were found to be very similar both quantitatively and dynamically; also, a combination of both mechanisms was very little more efficient than either one separately. False trail following is difficult to compare with the other two, since competition with wild females is involved and thus the total population size enters the equations. Density dependence of the action of pheromones results in some cases in which mating disruption cannot control the pest population. Similarly, aggregation of the pest population decreases the efficiency of the method unless the pheromone action is density independent. Delayed mating of females makes control easier, and may constitute one mechanism for mating disruption.     

Modelling the effects of population aggregation on the efficiency of insect pest control

Summary A methodology is developed to assess the effects of spatial distribution on the efficiency of insect pest control. This methodology is especially applicable to pest control methods whose efficiency of action depends either positively or negatively on pest density It is applied here to the sterile insect technique and pheromone trapping for male annihilation, which both depend negatively on density. This methodology relies on quantifying clumps of various size and then relating this to efficiency of control and predicting the total pest production given the information on clump sizes and efficiency of control for each clump size. It is found that control is about four times as difficult for a population that is highly clumped (k of the negative binomial distribution=0.25) as for a regularly dispersed population.     

Number of generations necessary to attain eradication of an insect pest with sterile insect release method: A model study

Summary Simulation of the sterile insect release process was carried out based on a system which consisted of a logistic population model and Poisson-binomial model for normal, sterile and combined matings. From the results, relationship between the intrinsic rate of natural increase and the sterile vs. normal ratio necessary to attain eradication of the target pest species were presented. The effects of weakened sperm competitiveness and the increased number of matings per female were not so strong. On the other hand, a given rate of immigration could be a cause of failure of the eradication. A simple method to calculate relationship between hatchability and sterile vs. normal ratio was presented.     

Combining methods of insect pest control: Partitioning mortality and predicting complementarity

Summary An age-structured population model is used as a vehicle for presenting a method for the analysis of interactions between pairs of insect pest control methods. This analysis is based on partitioning the total mortality acting on a population into its constituent components from all known sources. Pairwise critical mortality curves are then constructed which represent the combined mortality required for eradicating the pest population. Effort curves are then constructed from computing the mortality resulting from a given amount of control effort. The convolution of the critical mortality curves and the effort curves then yields the isoclines formed by the effort required of two control methods in combination to achieve eradication. This analysis allows the prediction of either synergism or interference between the control methods and also helps explain patterns observed in previous modelling of such combinations of pest control methods.     

Lifetime mating success of males in a natural population of the papilionid butterfly,Atrophaneura alcinous (Lepidoptera: Papilionidae)

Summary Lifetime mating success of males in a natural population of the papilionid butterfly,Atrophaneura alcinous, was investigated and causes of the variation were examined. The most successful males mated with 5 females, whereas about 73% of the males failed to mate. Body size of males was not correlated with their eclosion date, longevity and lifetime mating success. There was no trade-off between mating success and longevity, and long-lived males had a disproportionately high mating success. Although number of available females per male per day was not variable among males with different longevities, long-lived males had higher mating efficiency. Time interval between matings by non-virgin males was shorter than that from eclosion to the first mating. High lifetime mating success of long-lived males was strongly related to their mating experience, not to their ageper se.     

Spatial relationships between mate acquisition probability and aggregation size in a gregarious coreid bug, (Colpula lativentris): A case of the ideal free distribution under perceptual constraints

Summary Spatial relationships of mate acquisition probability for individuals of both sexes of a gregariously-mating coreid bug,Colpula lativentris, were studied in relation to aggregation size. Operational sex ratio was always strongly male biased. Mate acquisition probability of females was rather constant and independent of aggregation size, as predicted by an ideal free distribution. Moreover laboratory experiments showed that both multiple mating and rearing density little affected female fecundity, suggesting ideal free distribution of females in terms of reproductive success. On the other hand, mate acquisition probability of males was higher in larger aggregations, where more receptive females were available. This male discrepancy from an ideal free distribution was similar to the patterns predicted by an ideal free distribution under perceptual constraints (Abrahams, 1986), but not by that under unequal competitive ability.     

Impact of support networks for breastfeeding: A multicentre study

Background

The rates of breastfeeding worldwide are slowly improving since 1996. Europe is still trailing behind the global breastfeeding incidence and prevalence rates. Thus, breastfeeding promotion, protection, prolongation and support have become an important challenge as breastfeeding sharply decreases in the first six months of life.

Index of intensity of sexual selection: A comment on Nishida's article

Summary An index of intensity of sexual selection proposed by Nishida (1992: Res. Popul. Ecol. 34: 373–382) was examined. Two examples were presented to show that Nishida's index was not free from confounding effect of mortality schedule. Importance of removing the phylogenetic effects in comparative analyses was also discussed.     

人口结构变动对中国碳排放绩效的影响研究

本文首先使用非径向、非角度的SBM-Undesirable模型对我国30个省（市）区2000—2012年的碳排放绩效进行了测度,并利用Tobit模型进一步分析我国人口结构变动对各省（市）区碳排放绩效的影响。结果显示：（1）在样本考察期内,我国的碳排放绩效在逐渐提高,东部地区的碳排放绩效远高于全国及中西部地区的碳排放绩效,中部次之,西部最低;（2）劳动人口数量和受教育程度对我国的碳排放绩效具有正向的驱动作用,家庭规模的小型化、老龄化人口数量、人口城市化水平和经济增长对我国碳排放绩效的提高起阻碍作用。     

我国公共投资对就业影响的实证分析

本文运用向量自回归模型分析了中国的公共投资对就业总量和三次产业就业量的影响。经验分析表明增加公共投资能够带来就业增长,公共投资可调整就业结构。同时,公共投资对就业的影响存在2期滞后。而与非公共投资相比,公共投资在促进就业增长上的作用较小。     

International consensus definition of critical thinking in midwifery practice: A Delphi study

ProblemCurrently there is no discipline-specific definition of critical thinking in midwifery practice.BackgroundCritical thinking in midwifery practice is the cornerstone for safe, evidence based, and woman centred clinical decision-making. Available definitions of critical thinking in other disciplines do not align with midwifery practice which is distinctive, multidimensional and complex.AimTo develop an international consensus definition of critical thinking in midwifery practice.MethodsA two round Delphi study was used. Thirty-two international midwifery experts contributed to the first round which was qualitative in nature. Twenty one of these experts then ranked the relevance and clarity of concepts from round one.FindingsA consensus definition of critical thinking in midwifery practice was achieved. The expert panel identified and defined 14 ‘Habits of Mind’ and 12 Skills that are the core of critical thinking in midwifery practice. Skills included; analysis, constructive application and contextualisation of best available evidence, problem solving, discriminating, predicting, evaluation of care, collect and interpret clinical cues, collaboration/ negotiation, reflexivity, facilitates shared decision-making, communication, and transforming knowledge. Habits of Mind included; intellectual curiosity, reflective, holistic view, intellectual integrity, flexibility, questioning/challenging, participatory, open mindedness, listening with understanding and empathy, cultural humility, woman centred, being brave, confidence, and creativity.Discussion/conclusionThis study is an international first and delineates characteristics of critical thinking in midwifery. Development of a consensus definition provides a common and shared understanding of the skills and attributes required for critical thinking in midwifery practice and can also be applied in education and research.     

Assessing the Impact of Population Dynamics on Poverty Measures: A Decomposition Analysis

Social Indicators Research - Reducing income inequality is one of the seventeen Sustainable Development Goals recently announced by United Nations. A relative poverty concept adopted by...     

人口增长、城市化对环境的影响——以CO2排放为例

基于1978—2007中国宏观经济时间序列数据,利用协整回归方法和误差修正模型(ECM),实证分析了人口增长、城市化水平、人均GDP和能源强度对CO2排放的影响。结果显示,人口总量、城市化水平、人均GDP和能源强度与CO2排放存在长期均衡关系。长期来看,人口总量对CO2排放量的影响最大,城市化水平其次,人均GDP最小。短期来看,能源强度和人均GDP对CO2排放波动影响较大,而人口总量和城市化水平影响不显著。     

A simple method to estimate insect mortality from field census data: A modification of the Kiritani-Nakasuji-Manly method

Various methods have been proposed to estimate demographic parameters such as mortality from field census data. Simple methods proposed earlier are applicable only for limited situations. For example, the Kiritani-Nakasuji-Manly method is applicable only if individuals are observable until their death. Improved methods proposed later are not subject to such limitations, but are not so widely used in the field of applied entomology, probably because of the complexity of the calculations involved. In this paper, I propose an intermediate method that requires only a pocket calculator, considering the practical convenience for field scientists. This method, which is a modification of the Kiritani-Nakasuji-Manly method, gives an estimate of the number of individuals entering a stage from the frequency of two stages when the stage duration is known.     

Impact of the External Debt on Standard of Living: A Case of Asian Countries

Social Indicators Research - This study discusses the basic purpose of external debt: to finance poverty alleviation and bring progress in a country in a time of crisis rather than increase the...     

Risk factors of severity of abuse against older women in the home setting: A multinational European study

ABSTRACT

This article examines the ecological risk factors of abuse against older women. Data from 2,880 older women were randomly collected in five European countries (Austria, Belgium, Finland, Lithuania, and Portugal) using a standardized questionnaire. Results indicate that overall 30.1 % older women had at least one experience of abuse in the past year. The findings demonstrate that a single emphasis on personal risk factors (e.g., health, coping) is important but too simple: Abuse is multifaceted and is embedded in environmental (e.g., loneliness, household income) as well as macrocultural contexts (e.g., old age dependency ratio).     

A comparison of two versus four sterile water injections for the relief of back pain in labour: A multicentre randomised equivalence trial

BackgroundRecent trials demonstrated the safety and efficacy of sterile water injections to provide relief from labour back pain. While four injections is the most common approach variations in technique, such as employing two injections, are also used.AimTo determine if the analgesic effect of two sterile water injections is clinically equivalent to four.Methods238 women in labour with a Visual Analogue Scale pain score (VAS) of 70 millimetres (mm) (0 = no pain; 100 = worst pain imaginable) were randomised to two or four sterile water injections. The primary outcome was pain measured on a VAS at 30 min post treatment. A priori margin of equivalence was set at ±10 mm. Secondary outcomes included the likelihood of achieving an at least 30% and 50% reduction in pain, birth and neonatal outcomes.ResultsAt 30 min post-injection the difference in VAS scores between the techniques was ?5.97 (95% Confidence Interval [CI] ?13.18–1.22). As the lower end of the CI exceeds the margin of ?10 mm equivalence was not demonstrated. Both techniques achieved an at least 30% reduction in pain in over 75% of participants though duration of effect was longer in the four injection group. There was no difference in other birth related secondary outcomes.ConclusionFour injections provided a margin of benefit over two injections in level and duration of analgesia.DiscussionFour injections remains the technique of choice though two injections still provided significant pain relief and would be suitable where it was not possible or desirable to provide four.     

Mental Well-being Among Workers: A Cross-national Analysis of Job Insecurity Impact on the Workforce

Social Indicators Research - Drawing on 2011 and 2016 European Quality of Life Survey data from eight European countries, this paper considers the importance of subjective indicators of employment...