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We calculated extraction and production rates of bushmeat species in two main tropical, moist-for- est regions, the Amazon and Congo basins. Extraction was estimated from the average number of animals consumed per person per year from anthropological studies that reported animal kills brought into settle- ments in the regions. We calculated extraction rates (kg/km 2 /year) for 57 and 31 mammalian taxa in the Congo and Amazon, respectively. We then examined the sustainability of these extraction rates by basin and by taxa, using extraction-to-production ( E:P ) mass-balance equations. Production (tonnes/year) was calculated as the product of r max (the intrinsic rate of natural increase), mammal biomass, and total area of forest in each region. Species exploitation rates at specific body masses were significantly greater in the Congo than in the Amazon. The E:P ratio for the Congo was 2.4, 30 times the Amazon's ratio of 0.081. Thus, Congo Basin mammals must annually produce approximately 93% of their body mass to balance current extraction rates, whereas Amazonian mammals must produce only 4% of their body mass. We calculated sustainability levels derived from Robinson and Redford's harvest model for each taxa. On a basin-wide level, 60% and none of the mammal taxa in the Congo and Amazon basins, respectively, were exploited unsustainably. To evaluate the effect of error on the estimates of E:P , we conducted a sensitivity analysis, which suggests that the mass- balance was most sensitive to error in standing stock but that our results are robust. We estimated that over 5 million tons of wild mammal meat feed millions in Neotropical (0.15 million) and Afrotropical (4.9 mil- lion) forests annually. Our Congo basin estimates are four times higher than those calculated for the region by other workers, and we conclude that the current situation of bushmeat extraction in African rain forests is more precarious than previously thought.

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is a major polyphagous pest with the potential to seriously damage various crops. A better understanding of FAW's performance on different hosts may help to predict which plants will be attacked when the preferred host is absent, and facilitate the development of effective pest management practices. We compared the larval performance of FAW fed on maize with that of FAW fed on potato and tobacco, which are important crops in China, using an age-stage two-sex life table and adult female oviposition preference experiments. In cage experiments with potato, tobacco, or maize as the host, FAW reared on maize exhibited the strongest performance with shorter developmental time in the larval stage, longer longevity, and a higher reproductive rate in adults. Females oviposited on maize in preference to potato or tobacco. Compared with larvae fed on maize, those fed on potato and tobacco exhibited significantly lower survival, with only 31.61% and 8.13% developing to the adult stage, respectively. Several life table parameters, including the mean generation time (T), net reproductive rate (R0 ), finite rate of increase (λ), and intrinsic rate of natural increase (r) were negatively affected in FAW fed on potato and tobacco. Our results support the preference-performance hypothesis, that is, that herbivore females maximize fitness by choosing host plants associated with strong larval performance. Although larvae and adults performed poorly on potato and tobacco, their offspring will be capable of establishing populations on them, posing a potential threat to these crops in China.

Planktonic Oikopleura dioica respond almost instantly to opportunistic algal blooms, but it is unknown whether the population increase can change from an exponential to a logistic model to avoid a final sudden collapse. To test the hypothesis that intraspecific competition regulates the intrinsic rate of natural increase (r), density-dependent effects on growth and reproduction performance were investigated in O. dioica via laboratory incubations. Over a large food concentration range, batch maturation was observed above the per capita food supply (PFS) of 8.1 μg C/ind. in 4.5 d. Somatic growth was saturated beyond this PFS value, whereas gonad length increased continuously. Below this threshold, individuals reached small body and gonad lengths, and maturation was rarely observed during the incubation period. The gonad/body volume and maturation ratios also increased with the PFS. Instead of the food concentration, the r values were regulated by competition pressure via variability in maturation duration and the proportion of mature individuals in the cohorts. When the minimum food demand was satisfied in the designated generation time, the r value tended to be regulated by the spawning proportion in the population. Otherwise, prolonged development duration and decreased r values were expected.

This article "Socio-economic Aspects of European Union Migration Policy" is devoted to exploring the features, prerequisites and socio-economic factors that encourage developed EU countries to implement measures to attract third-country migrants. For this purpose, a brief overview of the geography of migration processes that took place in Europe from the time of the formation of the European Union to the time of its full functioning was carried out. Following the final formation of the Union in 1992, basic legal acts were adopted that outlined the general rules and procedures for migration, but each country resolves the main issues related to the economic aspects of migration. In 2015, one of the most important issues that will affect the future development of the EU was raised, namely the demographic crisis that affected almost all countries, and the importance of which began to be discussed at a high political level. Through numerous studies of the population and labor markets, it has emerged that the rate of natural increase of population in Europe is extremely low, and because of the increase in life expectancy of Europeans, the retirement age may exceed the economically active population in the near future, which will put a heavy strain on the pension, tax and social systems. The largest recipients of migrant workers in the EU Poland and Germany have long been aware of the need to respond to the growing demographic crisis and implement appropriate policies. Poland has undertaken a range of measures to minimize bureaucratic and permitting procedures for the employment of foreigners, and has introduced numerous economic incentives and benefits for migrants studying and working in Poland. As a result, millions of migrants support the Polish economy and the competitiveness of Polish businesses in European markets, and the contribution of migrants to GDP growth is highlighted by the country's leading economic institutions. Germany is pursuing a slightly different policy, but the adoption of the new migration law has proved that the country is already suffering from a shortage of manpower. Major forecasts from leading scientific institutions in the labor market indicate that Germany needs 200-400 thousand migrants annually to support economic growth. Although the analysis of the law shows that only skilled workers can obtain a work permit, but the situation may change in the near future, as the policy is prudent and gradually giving access to markets. General scientific methods were used in the article: analysis, synthesis, induction, deduction, statistical analysis.

In order to investigate the effect of Wolbachia on fitness of their hosts, the biological characteristics of a primarily parthenogenetic line and a bisexual restored line (obtained by antibiotic treatment) of Trichogramma pretiosum were compared in the laboratory. Results indicated that both the mean longevity and fecundity of parthenogenetic line (14.2 d and 165 eggs/female) were significantly higher than those in bisexual restored line (8.4 d and 124.2 eggs/female). Both lines of T. pretiosum had the highest daily fecundity (23.3 eggs/female for parthenogenetic line and 19.8 eggs/female for bisexual restored line) on the first day during their reproduction period, and their survival rate and daily fecundity decreased gradually with age; however, the survival rate and daily fecundity of the parthenogenetic line were always higher than those of bisexual restored line, during the entire experimental period. There was no significant difference in emergence rate and deformity rate between the two T. pretiosum lines. The life-table parameter results indicated that net reproduction rate (R0) and mean generation time (T) in parthenogenetic line (133 and 16.8) were significantly higher than those in bisexual restored line (61.7 and 15.5); intrinsic rate of natural increase (rm) and finite rate of increase (λ) in parthenogenetic line (0.29 and 1.34) were higher than those in bisexual restored line (0.26 and 1.3). Based on these results, it can be confirmed that the removal of Wolbachia in the parthenogenetic line had an adverse effect on fitness of T. pretiosum.

The clover mite, Bryobia praetiosa Koch (Acari: Tetranychidae), is an agricultural pest, as well as a frequent invader of hospitals and homes. However, its adaptability to different temperatures is not well understood. We used age- and stage-specific life tables to investigate the effects of temperature on demographic parameters of B. praetiosa from 15 to 35°C under a long-day photoperiod (16:8 [L:D] h). The clover mite is a thelytokous species (consisting of only females) due to its infection with the symbiotic bacterium Wolbachia. The egg-to-adult development time of female B. praetiosa decreased as the temperature increased from 15 to 32.5°C. At 35°C, females laid eggs, but no eggs hatched. The lower thermal threshold (t0) and the thermal constant (K) for egg-to-adult females were 8.7°C and 274.1 degree-days, respectively. The intrinsic optimum temperature (TØ) was 22.4°C. The oviposition period decreased with increasing temperature. Fecundity was highest at 20°C and extremely low at 30°C. The net reproductive rate (R0) decreased as the temperature increased from 15 to 30°C, but no significant difference was observed between 15 and 20°C. The intrinsic rate of natural increase (r) varied from 0.0721/d at 15°C to 0.1679/d at 25°C, and then decreased to 0.1203/d at 30°C. These results should be useful in developing management strategies for B. praetiosa.

Life history theory predicts that animals should increase their current reproductive effort as the probability of survival to the next reproductive opportunity decreases. We studied the effects of food depletion on life history and oviposition behavior in the egg parasitoid Paratelenomus saccharalis (Hymenoptera: Platygastridae) to determine if the parasitoid alters its reproductive strategy based on life expectancy. We first examined survivorship and reproductive effort of females provided only with water (i.e. starved) and females fed honey. Fed females lived up to 40 days, whereas starved females lived only up to 4 days. Fed females produced more offspring during life and had a higher net reproductive rate, i.e. R0, compared to starved females. Starved females did produce more offspring on the first day of emergence, however, and the intrinsic rate of natural increase, i.e. rm, did not differ between honey-fed and starved females. We further observed oviposition behavior in response to food availability during 24 h on the first day of emergence to determine the mechanism by which starved females increased reproductive output. Results showed that starved females oviposited more frequently than honey-fed females, and that the time required for a single oviposition was shorter for starved females. These results revealed that starved females had higher oviposition rates on the first day of emergence, leading to the similar rm of starved and fed females. This indicates that P. saccharalis altered their oviposition behavior to maximize their fitness under food-depleted conditions.

Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), one of the most destructive pests of tomato, has recently invaded India. Before recommending any bio-control agent for its control, it is important to study the demographic parameters of the bio-agent on the pest. The present study evaluates the demographic parameters of indigenous trichogrammatids namely Trichogramma achaeae Nagaraja and Nagarkatti, T. pretiosum Riley, T. chilonis (Ishii), and T. pieridis Nagaraja and Prashanth against this pest, aiming to select the most effective egg parasitoid species. Significant differences were observed among the demographic parameters of different Trichogramma spp. Parasitization potential of a thelytokous strain of T. pretiosum was the highest, followed by T. achaeae, T. chilonis, and T. pieridis. Population growth parameters net reproductive rate, intrinsic rate of natural increase, finite rate of increase, and weekly multiplication rate were highest, and generation time and doubling period were shortest for T. pretiosum, followed by T. achaeae, T. chilonis, and T. pieridis. The study concluded that T. pretiosum could be considered a potential candidate for biological control of T. absoluta; however, field evaluation is required before final recommendation.

The objectives of this study were to evaluate the impacts of infant and elderly underenumeration and age estimation error on previously reported measures derived from the D0–14/D ratio, specifically total fertility rate and the rate of natural increase. This study used data from the United Nations database for the year 1960. A two-step approach was taken: to test the stability of the relationship we examined the correlation between the D0–14/D ratio and population dynamics of interest with data omitted or misclassified to simulate a range of sample underrepresentation and age estimation error scenarios. To evaluate the practical implications, we used our existing equations to estimate total fertility and natural increase rates using the simulated differentially represented samples and calculated the standard error of the estimate. Correlations remained robust until a small number of infants and the elderly were represented. Where both infants and the elderly were underrepresented, as much as 75% of these age categories could be removed before accuracy of the equations was significantly compromised. Where either infant underenumeration or elderly underenumeration is suspected, our palaeodemographic measures maintain accuracy when up to 25% of the sample is missing. Age estimation error had a negligible impact. These measures demonstrated robusticity in a range of sample underenumeration scenarios, particularly for sources of bias that impact both infants and the elderly equally, and age estimation error. Where either infants or the elderly have been significantly underrepresented or omitted from the burial site, alternative measures may be required.

Populations are permanently evolving and their evolution will influence their survival and reproduction, which will then alter demographic parameters. Several phenotypic, life history and environmental variables are known to be related to fitness measures. The goal of this article was to look into the possible types of those relationships in insects of the subfamily Triatominae, vectors ofTrypanosoma cruzi, the causative agent of Chagas disease. After an exhaustive literature review of 7,207 records of publications referring exclusively to all possible features of the triatomines, using 15 keywords those records were reduced to 2,968 publications, that were analyzed individually; after deleting those publications that did not have the data in quantitative form as needed for the objective of this article, I found that 171 papers were adequate for the present analysis. From them I compiled a dataset of 11 variables and 90 cases from 36 triatomine species. Those variables included four environmental, two life cycle, and four morphological variables, and one demographic parameter: a fitness measure (the population intrinsic rate of natural increase,r0), used as dependent variable. However, the relationship betweenT. cruziand its vector host was not included in this analysis despite triatomine-T. cruziinteractions constitute an important factor in the evolution of triatomine’s life history. I resorted to the Random Forest method as a machine learning approach for the analysis of this dataset, and found that –in addition to the triatomine species themselves– only the two life cycle variables (mean development time from egg to adult, and mean fecundity, expressed as the average number of female eggs laid per female per day) were statistically significant in determining fitness (r0). The machine learning approach used in the analysis provided a similar but deeper insight into these relationships than classical regression. Except for an analysis on senescence, this is the first study in triatomines addressing these questions. These results will be useful for other theoretical optimization approaches (frequency-dependence, density-dependence, evolutionary game theory, and adaptive dynamics), thus contributing to the theoretical framework for interpreting the succession of stages in insect adaptations, a framework yet to be constructed.

The process of demographic transition changes the demographic characteristics of any country, this transitions have had economic and social implications, whether long or short-term. Sudan is now in the second phase of demographic transition. This paper aims to studies the impact of demographic transition on economic growth of Sudan. The study used short time series from 1990 to 2019 and the data have collected from Central Bureau of Statistics (Sudan). The Autoregressive Distributed Lag (ARDL) model has been applied. The study results showed a positively impact for the demographic transition on economic growth in Sudan in the long run and negatively in the short run, {"references":["Ahmed, H. M. (2014). The Socio-Economic and Political Impacts of Youth Bulge: The Case of Sudan, Journal of Social Science Studies, 1(2), pp. 224-235","An, C. B., Jeon, S. H. (2006). Demographic changes and economic growth in Korea. In APEA Conference, pp. 103-113.","Benamra, A., Aznag, F. (2020). The main sources of domestic inflation in the short term The Case of Algeria. Journal of Economic Growth and Entrepreneurship, 5(1), pp.115-128. https://www.asjp.cerist.dz/en/article/138994","Bloom, D. E., Canning, D., Sevilla, J. (2001). Economic growth and the demographic transition (No. w8685), National Bureau of Economic Research. . http://www.nber.org/papers/w8685","Fekir, K. Yousfat, A. (2020). The Impact Of Diversification In Income Sources On Economic Growth. Journal of Economic Growth and Entrepreneurship, 4(2), pp.59-72. https://www.asjp.cerist.dz/en/article/128316","Feng, W. (2011). The future of a demographic overachiever: Long-term implications of the demographic transition in China. Population and development review, 37, pp. 173-190.","Feyrer, J. (2007). Demographics and productivity. The Review of Economics and Statistics, 89(1), pp100-109.","Galor, O. (2005). The demographic transition and the emergence of sustained economic growth. Journal of the European Economic Association, 3(2), pp. 494-504.","Greenwood, J., Seshadri, A. (2002). The US demographic transition. American Economic Review, 92(2), pp. 153-159.","Hussain, S., Malik, S., Hayat, M. K. (2009). Demographic transition and economic growth in Pakistan. European Journal of Scientific Research, 31(3), pp. 491-499.","Iqbal, K., Yasmin, N., Yaseen, M. R. (2015). Impact of demographic transition on economic growth of Pakistan. Journal of Finance and Economics, 3(2), pp. 44-50.","Kuznets, S. (1973). Modern economic growth: findings and reflections. The American economic review, 63(3), pp. 247-258.","Mboup, G., Saha, T. (1998). Fertility Levels, Trends, and Differentials: Demographic and Health Surveys. Comparative Study, (28), pp. 77.","Razika, M. (2020). Entrepreneurship as a mechanism for national economy growth. Journal of Economic Growth and Entrepreneurship, 4(2), pp.1-14. https://www.asjp.cerist.dz/en/article/128312","United Nations. (2019). World Population Prospects 2019: the 2019 Revision, Department of Economic and Social Affairs, Population Dynamics. Accessed 10/12/20 at «https://population.un.org/wpp/»."]}

Life history theory examines how characteristics of organisms, such as age and size at maturity, may vary through natural selection as evolutionary responses that optimize fitness. Here we ask how predictions of age and size at maturity differ for the three classical fitness functions-intrinsic rate of natural increase r, net reproductive rate R0, and reproductive value Vx-for semelparous species. We show that different choices of fitness functions can lead to very different predictions of species behavior. In one's efforts to understand an organism's behavior and to develop effective conservation and management policies, the choice of fitness function matters. The central ingredient of our approach is the maturation reaction norm (MRN), which describes how optimal age and size at maturation vary with growth rate or mortality rate. We develop a practical geometric construction of MRNs that allows us to include different growth functions (linear growth and nonlinear von Bertalanffy growth in length) and develop two-dimensional MRNs useful for quantifying growth-mortality trade-offs. We relate our approach to Beverton-Holt life history invariants and to the Stearns-Koella categorization of MRNs. We conclude with a detailed discussion of life history parameters for Great Lakes Chinook Salmon and demonstrate that age and size at maturity are consistent with predictions using R0 (but not r or Vx) as the underlying fitness function.

Dactylopius opuntiae is the most important pest of cactus (Opuntia ficus-indica) around the world. Recently the scale-supping pest have become an increasing threat to the cultivation of prickly pear in many Mediterranean areas. The life cycle of D. opuntiae was carried out under field and semi-field in Winter-Spring and Spring-Summer Morocco conditions. The results showed that the duration of life cycle of D. opuntiae under field and semi-field conditions was temperature dependent. It was long (133.52±3.82 days) in Winter-Spring when temperature was between 2.3°C and 25°C than in Spring-Summer (127.85±2.15 days) when the temperature was between 13.5°C and 47°C. Duration of male life cycle was significantly long under field conditions in Winter-Spring (74.57±4.05 days) and short (37.10±3.0 days) under semi-field conditions in Spring-Summer. For the duration of female life cycle it was significantly long (133.52±3.82 days) under field conditions in Winter-Spring, and no significant difference was observed between field conditions in Spring-Summer, semi-field conditions in Spring-Summer, and semi-field conditions in Winter-Spring. The effect of the availability of food on reproduction and population growth parameters was also evaluated under laboratory conditions at 25 ±2°C and the results indicated that the females pre-oviposition, and post-oviposition periods were significantly long without food than in the presence of food, however oviposition period, females longevity, fecundity, fertility, and growth index were significantly higher in the presence of food than without food. Also the net reproductive rate (R0), and generation time (T) were significantly higher for females with food, and no significant difference was observed between females with food and females without food for intrinsic rate of natural increase (rm), doubling time (DT), and finite rate of increase (λ).

The life history features of the invasive snail Physa acuta occurring in Kolkata was assessed emphasizing the growth and the life table parameters. The growth observed in terms of the weekly changes in the shell length and body weight for a cohort complied with the von Bertalanffy growth equations (for shell length: Lt = 13.651 * (1 − exp(−0.161(t−0.55)) and for body weight Wt = 86.30 * (1 − exp(−0.161(t−0.55))1.811. The generation time (Tc), the net reproductive rate (R0), the intrinsic rate of natural increase (rm) and the finite rate of increase (λ), were respectively, 47.36 days, 644.64, 0.13 and 1.14, which are comparable to the findings made on the P. acuta in other parts of the world. Variations in the life history of P. acuta may be possible if considered over the newly invaded habitats in West Bengal, India. Although the snails are restricted to the sewage drain habitats, in Kolkata, India, the results are indicative of the prospective invasion of the snails to other freshwater habitats, if appropriate measures to control the population are not adopted.

The aim of this study was to provide a verifiable measure of population increase from age-at-death data. It was anticipated that the D0-14/D ratio would be a good predictor of the rate of natural increase (births minus deaths) due to its strong relationship with the total fertility rate. United Nations age-at-death data for 58 countries was used to calculate the rate of natural population increase and evaluate its relationship to the D0-14/D ratio. Additionally, the impact of migration on both the rate and the ratio was measured. A correlation of r = 0.863 (95% CI 0.777–0.917) between the D0-14/D ratio and rate of natural population increase was found. Linear regression provided a simple equation for calculating the rate of population increase. The rate of natural population increase accounts for the disparity (or lack of) between births and deaths, and provides a valuable measure for evaluating ancient population variability. While the rate does not factor in migration, we believe migration should be measured independently as it is not always of interest to bioarcheological research questions and has a negligible impact on the rate of natural increase and the D0-14/D ratio. Estimating the rate of natural population increase has the potential to provide significant insights into past populations and the human response to change.

The aim of the article is to highlight how demographic changes in Poland and projections for the coming years can affect the operation of and the need for changes in formal education establishments run by gminas (municipalities), especially rural ones. Trends concerning changes in population growth, especially in terms of birthrate and rate of natural increase, affect the emerging baby booms and busts in different age groups of children and youth attending schools at each grade. It is important that all grades of education take into account the changing age structure of the population, the need for teachers to make their students aware of the need for lifelong learning because of changes in future labor resources, and to provide quality education in response to labor market challenges. Demographic changes also affect the structure of expenditures earmarked by a gmina for education. The funds available to most gminas from education subsidies do not cover the costs of educational establishment operation. If the number of pupils falls, the amount of the educational subsidy decreases, the costs of running a school remaining at a constant level, which exacerbates its financial standing. The role of gmina authorities is to take into account demographic challenges in managing the network of schools and other educational establishments. This involves consolidation activities. Institutions running educational establishments should also take into account other social risks resulting from population projections, such as the aging process, including aging of the teachers’ group and a declining number of youth pursuing studies at tertiary education establishments.

In order to gain insights into the seasonal dynamics of genetic variation in insecticide resistance within a natural population of Drosophila melanogaster during population growth, which we considered the most important ecological factor there, we conducted a series of genetic analyses of resistance factors involved in that population and compared individual-based intrinsic rates of natural increase among resistance genotypes. However, some researchers have argued that it is a misconception to apply the intrinsic rate of natural increase to individuals, because it is a population parameter. We consider that their criticisms were incorrect. In this article, I described our research briefly and set forth the reasons why we conducted these studies.

The study aimed to detect the expectations of life expectancy of women since birth according to the diversity of the communities and to examine the most important social, cultural, economic, and demographic determinants. These have been identified as: the proportion of annual population increase, rates of infant mortality, the rate of the crude death, the rate of population density per cubic meter, the population of the state, the period during which the population doubles, the total fertility rate, the rate of birth control use, the level of individual income, the proportion of youth in the community (population less than 15 years), and the rate of urbanization. The study relied on the annual global data for 242 countries provided by the United Nations for all countries in the world which is known as the World Population Data Sheet. The study found that females live longer than males, and variables such as infant mortality, the proportion of youth in a community, the rate of crude mortality, total fertility of women and rate, and the relative use of birth control methods in the community, all play an influential role in determining the levels of the woman’s life expectancy.

The tomato fruitfly, Bactrocera tau (Walker) (Diptera: Tephritidae) is one of the most important pests of the family Cucurbitaceae. Toinvestigate local adaptation, we measured the variations in life-histories and life-table parameters among populations from five different geographical regions of North India, Ludhiana (262 mt amsl), Solan (1,502 mt amsl), Hisar (215 mt amsl), Pantnagar (344 mt amsl) and Jaach (733 mt amsl). The principal components analysis showed the life-history and life-table parameters of B. tau differed among the five geographical populations. The highest fecundity of 233.20 eggs/female was recorded in the Jaach population and was statistically at par with Hisar (209.21 eggs/female) followed by Solan (202.60 eggs/female), Pantnagar (178.60 eggs/female) and Ludhiana population (105.88 eggs/female). The total developmental period among the five populations of B. tau was the longest for the Pantnagar population (16.20 days) followed by Solan (13.90 days), Hisar (12.60 days), Ludhiana (12.30 days) and Jaach (11.60 days). The true intrinsic rate of natural increase (rm) was 0.120, 0.138, 0.140, 0.116 and 0.153 for the respective geographical regions while the finite rate of increase (λ) was 1.13, 1.15, 1.15, 1.12 and 1.16, thus indicating that the fruit fly from Jaach location is more reproductive than the other five geographical regions of North India. Since the study will be useful in knowing the multiplication rate of fruit fly in specific area, accordingly the management practices for this species can be formulated on the bases of these studies. The results thus indicated the geographical variations among different populations of B. tau.

Several aspects of the population dynamic of Fannia pusio (Wiedemann, 1830) were studied in the laboratory. Adults were collected at granja Capuavinha, located in the municipality of Monte-Mor, approximately 30 km from Campinas, and in the vicinity of the Department of Parasitology, Universidade Estadual de Campinas. Adults were kept in the laboratory and were fed with powdered milk, sugar and brewers yeast. Water was offered in separate vials. Fermented food for laboratory animals was used as oviposition medium. The percentages of eclosion eggs was high at 20C, with 69,25% and 33C , with 72,5%. The development time decreased with the increase of temperature from 132 h at 10C to 19 h at 33C. F. pusio showed synchronization in the eclosion of its eggs. Larvae presented a sigmoid growth curve, with a fast rate of growth at the beginning. At 20C the larvae attained the maximun weight between 138 and 162 hs; at 27C and 33C, between 90 and 114 hours; the average time for larval development at 20C was 96,5 hs; and at 27C and 33C, this time was 63 hours. There were no significant weight and development time differences at the three temperatures. Pupation began between 210 and 234 hours at 20C, and between 138 and 162 hours at 27C and 33C. Development times of pupas were significantly different for the three temperatures. Adult longevity was greater at 20C, followed by 27 C. Longevity decreased with temperature increase and, at all temperatures, females lived longer than males. Fecundity also varied with temperature, and the greater fecundity occurred at 27C. Most oviposition peaks were observed in the first few days. The reproductive rate (RO) and the rate of natural increase (Rm) were higher at 27C, with rates of 48,18 and 0.1849, respectively. The greater generation time occurred at 20C, but the population growth was positive at all temperatures. F. pusio presented a pattern of adult emergence, with males emerging first. Most adults emerged during the light period 37% of the individuals emerging between 10 and 12 hours. Key words: Diptera, fly, manure of chicken, biology. Source: Arquivos de Ciencias Veterinarias e Zoologia da UNIPAR (Impresso). , v.7, p.187 - 188, 2004.

The life table of the indigenous Neoseiulus californicus was studied at different temperatures and 65 ± 5% relative humidity under conditions of 16 h light : 8 h dark (LD 16:8). The total developmental period from egg to adult varied from 3.0 to 14.0 days at 15 to 35°C. Survival to adulthood ranges from 86.21 to 93.94%, with the highest rate at 25°C. The lower threshold temperature from egg to adult stages of females and males was 10.84 and 10.72°C, respectively, and the thermal constant was 57.14 degree-days (DD) for females and 56.18 DD for males. Total number of eggs laid by each female was the highest (70.38 eggs) at 25°C, whereas average daily fecundity was the highest (3.69 eggs/female/day) at 30°C. The net reproductive rate was the highest (48.49) at 25°C and lowest (26.18) at 30°C. Mean generation time decreased from 19.04 to 11.47 days with increasing temperature from 20 to 30°C. Both intrinsic rate of natural increase (0.284) and finite rate of increase (1.32) were maximum at 30°C. Adult longevity was the highest (42.75 days for females and 32.60 days for males) at 20°C and lowest (22.70 days for females and 15.30 days for males) at 30°C. Sex ratio was female biased and was the highest (78.08) at 25°C and lowest (70.24) at 30°C. Developmental data of five constant temperatures, temperature thresholds and thermal requirements may be used to predict the occurrence, number of generations and population dynamics of N. californicus as an important biocontrol agent of Tetranychus urticae.

The article looks at regional segment in the demographic processes in Kazakhstan during the decade of 1999-2009. The author uses method of cluster analysis to study demographic zones that includes specific weights of: a) Russian and Kazakh population in the total structure of the population, b) urban population in the total structure of population, c) people over 65, d) women of fertile age between 15 and 44, e) cumulative rate of natality, f) general mortality rate, g) rate of natural increase and h) crude marriage and divorce. These criteria enabled to distinguish several clusters using the concept of ‘ethnic and demographic area’ denoting a territory with relatively homogenous demography. Five clusters described comprise 1) Mangystau region, 2) region that includes East and North Kazakhstan with Akmola and Kokshetau, 3) South Kazakhstan with Atyrau and Kyzylorda, 4) Karaganda and Pavlodar regions (oblasts), 5) Aktobe, Almaty, Zhambyl and Western Kazakhstan region. Analysis of these areas made it possible to reveal their specific features. Differences between regions turned out to be substantial. While demographic situation in Mangystau and South Kazakhstan with Akmola and Kokshetau was favorable, demographic trends were negative in Eastern, Northern Kazakhstan and Akmola and Kokshetau regions as well as Karaganda and Pavlodar regions. Demographic trends in Aktobe, Almaty, Zhambyl regions and Western Kazakhstan can be characterized as transitional one from negative to positive extremes revealed between other two groups of clusters. The study of fertility in various regions of Kazakhstan allowed distinguishing two periods the first one being the 1989-1999s, when fertility declined dramatically and the period of its rise during the 1999-2009s. The article also discusses regional particularities of morality and reproduction in Kazakhstan, which are also determined by ethnic composition of these regions.

This study considers the spatial and temporal dimensions of demographic trends in Serbia between 1961 and 2010. Using appropriate spatial autocorrelation statistics, spatial patterns of common demographic indicators including changes in population size, the rate of natural increase and infant mortality rate are investigated across municipalities of Serbia. Also, the impact of differential demographic rates according to ethnic origin on forming spatial clusters is implicitly considered. Different stages of demographic transition across municipalities at the start of the analyzed period determined the spatial pattern of clustered subregions; ethnic origin appeared to be a strong factor of differentiation regarding population dynamics. The two opposed areas regarding the transition of rates of natural increase and infant mortality were clustered; the southern included Kosovo and the least developed subregions of Central Serbia. The City of Belgrade and Kosovo have been the two hubs of population growth in Serbia over the past 50 years, while the strongest depopulation refers to the north and east border regions.

Ephestia kuehniella Zeller, is a major pest in stored products, and a host resurgence for rear natural enemies. Understanding the relation between temperature variations and the life table parameters of E. kuheniella is necessary to predicting its population dynamics and improve the efficiency of mass rearing through determining the optimal temperature. The influence of seven temperatures (15, 17.5, 20, 22.5, 25, 27.5 and 30 °C) on the development, reproduction and survival of E. kuehniella were tested under laboratory conditions. Development time of almost all immature stages in E. kuheniella was the shortest at temperatures of 30, while the longevity of male and female decreased with increasing temperatures. At 27.5 °C E. kuheniella females had the highest intrinsic rate of natural increase (0.07111 d−1), and finite rate of increase (1.077 d−1). All demographic parameters showed a parabolic relation with temperature. The consequences of the present research showed that the temperatures between 25 °C to 27 °C, were most favorable for the reproduction and development of E. kuheniella and that for mass rearing in this species and predict E. kuheniella population phenology and dynamics.

The dramatic 1988–1996 fertility decline and negative rate of natural increase in Russia after 1992 shocked public officials and many others around the world. In Russia, family procreative plans are modified by individual proclivities, state of health, and specific circumstances. The transition from abortion as the means of birth control to more modern means of family planning in Russia is in an early stage. It is clear that beginning in the 1970s, the earlier convergence of demographic processes between Russia and other economically advanced countries reversed. Demographic changes that occurred in developed countries over the last two decades were so substantial as to be labeled the second demographic transition. The hypothesis regarding the commencement of the second demographic transition in Russia was a point of departure for a fertility forecast prepared as part of a 1994 general demographic forecast by the Center for Demography and Human Ecology.

Triatoma infestans (Klug, 1834) (Hemiptera: Reduviidae), the main vector of Chagas disease in South America, feeds primarily on humans, but ethical reasons preclude carrying out demographical studies using people. Thus, most laboratory studies of T. infestans are conducted using bird or mammal live hosts that may result in different demographic parameters from those obtained on human blood. Therefore, it is of interest to determine whether the use of an artificial feeder with human blood would be operational to rear triatomines and estimate population growth rates. We estimated life history traits and demographic parameters using an artificial feeder with human blood and compared them with those obtained on live hens. Both groups of T. infestans were kept under constant conditions [28 6 1C, 40 6 5% relative humidity, a photoperiod of 12:12 (L:D) h] and fed weekly. On the basis of age-specific survival and age-specific fecundity, we calculated the intrinsic rate of natural increase (r), the finite rate of population growth (k), the net reproductive rate (Ro), and the mean generation time (Tg). Our results show differences in life history traits between blood sources, resulting in smaller population growth rates on human blood than on live hens. Although demographic growth rate was smaller on human blood than on hens, it still remains positive, so the benefit/cost ratio of this feeding method seems relatively attractive. We discuss possibility of using the artificial feeder with human blood for both ecological and behavioral studies. Fil: Medone, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentina Fil: Balsalobre, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentina Fil: Rabinovich, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentina Fil: Marti, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentina Fil: Frédéric, Menu. Laboratory Of Biometry And Evolutionary Biology; Francia. Claude Bernard University; Francia

We present a general and flexible mathematical model (called SANDY) that can be used to describe many biological phenomena, including the phenology of arthropods. In this paper, we demonstrate how the model can be fitted to vital rates (i.e., rates associated with development, survival, hatching, and oviposition) of the two-spotted spider mite (Tetranychus urticae (Koch)) exposed to different constant temperatures ranging from 15°C to 37.5°C. SANDY was incorporated into an age-, stage- and sex-structured dynamic model, which was fitted to cohort life-tables of T. urticae conducted at five constant temperatures (15, 20, 25, 30, and 35°C). Age- and temperature-dependent vital rates for the three main stages (eggs, immatures, and adults) constituting the life-cycle of mites were adequately described by the SANDY model. The modeling approach allows for simulating the growth of a population in a variable environment. We compared the predicted net reproductive rate (R0) and intrinsic rate of natural increase (rm) at fluctuating temperatures with empirical values obtained from life-table experiments conducted at temperatures that changed with a daily amplitude (±0, ±3, ±6, ±9, and ±12°C) around an average of 22°C. Results show that R0 decreases with increasing amplitude, while rm is more robust to variable temperatures. An advantage of SANDY is that the same simple mathematical expression can be applied to describe all the vital rates. Besides, the approach is not confined to modeling the influence of a single factor on population growth but allows for incorporating the combined effect of several limiting factors, provided that the combined effect of the factors is multiplicative.

We used data on number of carcasses of wildlife species sold in 79 bushmeat markets in a region of Nigeria and Cameroon to assess whether species composition of a market could be explained by anthropogenic pressures and environmental variables around each market. More than 45 mammal species from 9 orders were traded across all markets; mostly ungulates and rodents. For each market, we determined median body mass, species diversity (game diversity), and taxa that were principal contributors to the total number of carcasses for sale (game dominance). Human population density in surrounding areas was significantly and negatively related to the percentage ungulates and primates sold in markets and significantly and positively related to the proportion of rodents. The proportion of carnivores sold was higher in markets with high human population densities. Proportion of small-bodied mammals ( 10 kg) decreased as human population density increased. We calculated an index of game depletion (GDI) for each market from the sum of the total number of carcasses traded per annum and species, weighted by the intrinsic rate of natural increase (rmax ) of each species, divided by individuals traded in a market. The GDI of a market increased as the proportion of fast-reproducing species (highest rmax ) increased and as the representation of species with lowest rmax (slow-reproducing) decreased. The best explanatory factor for a market's GDI was anthropogenic pressure-road density, human settlements with >3000 inhabitants, and nonforest vegetation. High and low GDI were significantly differentiated by human density and human settlements with >3000 inhabitants. Our results provided empirical evidence that human activity is correlated with more depleted bushmeat faunas and can be used as a proxy to determine areas in need of conservation action.

Key words: Growth, rates, poor, population, richAbstract. Human populations have grown at an unprecedented rate over the past three centuries. By 2001, the world population stood at 6.2 billion people. If the current trend of 1.4 % per year persists, the population will double in 51years. Most of that growth will occur in the less developed countries of Asia, Africa, and Latin America. There is a serious concern that the number of humans in the world and our impact on the environment will overload the life support systems of the earth. The crude birth rate is the number of births in a year divided by the average population. A more accurate measure of growth is the general fertility rate, which takes into account the age structure and fecundity of the population. The crude birth rate minus the crude death rate gives the rate of natural increase. When this rate reaches a level at which people are just replacing themselves, zero population growth is achieved. In the more highly developed countries of the world, growth has slowed are even reversed in recent years so that without immigration from other areas, population would be declining. The change from high birth and death rates that accompanies in industrialization is called a demographic transition. Many developing nations have already begun this transition. Death rates have fallen, but birth rates remain high. Some demographers believe that as infant mortality drops and economic development progresses so that people in these countries can be sure of secure future, they will complete the transition to a stable population or a high standard living. While larger populations bring many problems, they also may be a valuable resource of energy, intelligence, and enterprise that will make it possible to overcome resource limitation problems. A social just view argues that a more equitable distribution of wealth might reduce both excess population growth and environmental degradation. We have many more options now for controlling fertility than were available to our ancestors. Some techniques are safer than those available earlier; many are easier and more pleasant to use. Sometimes it takes deep changes in a culture to make family planning programs successful. Among these changes are improved social, educational, and economic status for women; higher values on individual children; accepting responsibility for our own lives; social security and political stability that give people the means and confidence to plan for the future; and knowledge, availability, and use of effective and acceptable means of birth control.Palabras claves: Crecimiento, poblacion, pobre, rico, tasaResumen. La poblacion humana ha crecido a una tasa inprecedente en los ultimos tres siglos. Para 2001 la poblacion mundial llego a 6.2 billiones. A una tasa actual de crecimiento de 1.4% annual, la poblaciona se duplicara en 51 anos. La mayoria del crecimiento ocurrira en los paises en via de desarrollo de Asia, Africa, y Latino America. Hay una preocupacion de que la poplacion humana y su impacto negativo sobre el medio ambiente pondra en peligro la existencia de los sytemas de soporte vital del mundo. La tasa cruda de nacimineto es el numero de nacimientos entre el promedio de la poblacion. Una medida mas exacta de crecimiento poblacional es la tasa general de fertilidad que toma en cuenta la estructura de la poblacion y la fecundidad poblacional. La diferencia entre la tasa cruda de nacimiento y la mortalidad nos da la tasa natural de incremento. Cuando esta tasa alcanza el nivel al cual la gente solamente remplaza a si mismo numericamente, se obtiene la tasa cero de crecimiento poblacional. En los países avanzadas del mundo, el crecimiento ha sido reducido o ha puesto en forma negativa, de tal modo que sin inmigracion en estos paises, la poblacion estará disminuyendo. El cambio de las tasas altas de nacimiento y mortalidad a las tasa bajas se denomina la transición demografica. Muchos países desarrolldos han empezado esta transición demográfica. La tasa de mortanda ha bajado en estos países sin que disminuyera la tasa de nacimiento. A medida que la tasa de mortalidad infantil se reduzca en estos países y la economía progresa mas y trae seguridad económico para la gente, entonces será possible una transición demográfica a una poblacion estable o un estandard de vida mas alta. Mientras que las poblaciones grandes traen muchos problemas, tamien pueden servir como recursos de enegia e inteligencia que permiten controlar el problema de la limitación de los recursos. Una idea de la justicia social argumenta que una distribución mas equitativa del capital puede reducir tanto el crecimiento excesivo poblacional como problemas ambientales. Hay muchos métodos de control de fertilidad en comparación con antes. Algunas técnicas son mas seguros, mas fácil de usar y mas placenteras que antes. Se requiere de cambios profundos culturales, como mejoramiento de estatus social, educacional, y económico, valores mas altos de los jóvenes, aceptar la responsabilidad en la vida, seguridad social, estabilidad política, el conocimiento, y el uso efectivo de medidas de control de natalidad, para permitir que la gente planea con seguridad hacia el futuro.

Information on the effect of temperature on biological parameters of phytophagous insects is one of the tools in IPM programs, as it allows prediction of risk situations in the field. This work reports the effect of temperature on reproductive parameters and longevity of one of the most important current pests of almond orchards in the Mediterranean basin, the poplar lace bug, Monosteira unicostata (Mulsant & Rey) (Hemiptera: Tingidae). The temperatures tested were 22, 25, 28, 31, 34 and 37ºC, always at 60 ± 10% relative humidity and under a L16:D8 photoperiod. Extreme temperatures had an adverse effect on preoviposition period, total fecundity and daily fecundity while increasing values of oviposition period and adults longevity were registered for decreasing temperatures. Male longevity was higher than female longevity, and mortality pattern differed between sexes for all temperatures but 37ºC. The nonlinear Lactin model described accurately the effect of temperature on the intrinsic rate of natural increase of M. unicostata populations and predicted the optimum temperature for population increase at 34.1ºC, at which the population doubling time is 3.6 days. Produced values of lower and upper thresholds for M. unicostata populations were 14.8 and 38.8ºC, respectively. This characterizes the poplar lace bug as a very important pest in the Mediterranean basin, with an increasing potential risk in a global warming scenario.

The demographic parameters of brown mite, Bryobia rubrioculus Scheuten were carried out in order to characterize the population growth potential at five constant temperatures: 20, 22.5, 25, 27.5 and 30 o C, 60 ± 5 % RH and 16: 8 (L: D) h. The highest intrinsic rate of natural increase ( r m = 0.0243/day), net reproductive rate ( R 0 = 2.4 ♀/♀/T) and finite rate of increase (λ = 1.0245 day -1 ) values were determined at 22.5°C. The mean generation time (T) of the population ranged from 22.7 days at 30°C to 45.8 days at 20°C. The maximum and minimum survival rates ( l x ) were recorded at 22.5oC and 30oC. Survivorship data ( lx ) of adult females were summarized and compared using the shape and scale parameters of the Weibull frequency distribution model across. The age specific fecundity data ( m x ) was modeled as a function of time by using Polynomial model. The lower temperature threshold ( t ) and thermal constant ( k ) of the immature stages were estimated using Ikemoto and Takai linear model to be 12.85 o C and 279.7 degree days (DD), respectively. Of the non-linear models, the Analitis-1, Analitis-2, Analitis-3 and Analitis/Allahyari models were found to be the best for the modeling development rate of immature stages of B. rubrioculus . The optimal temperature for population growth of brown mite on apple was found at 22.5°C.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a fruit pest of Asian origin that invaded North America in 2008. Despite the widespread economic impact of this species, much of the biology and general life history of this pest remains largely unknown. Under optimal laboratory conditions (22 degrees C, approximately 25% relative humidity), we measured development, survival, fecundity, hatch rate, and sex ratio of a North American ecotype of D. suzukii. Life history traits were used to construct a life table and reproductive schedule, and to calculate the intrinsic rate of population increase. The mean (+/- SE) total lifespan (egg to adult mortality) was 86.1 +/- 4.25 d, with a maximum value of 153.7 d. On average, females produced 5.7 +/- 0.24 eggs per day, with a mean total lifetime production of 635.6 eggs. The gross reproductive rate was 317.8 daughter eggs per female and the net reproductive rate was 240.4 daughter eggs per female. The intrinsic rate of natural increase was 0.179. The stable age distribution (c(x)) was comprised of 51% larvae, 25% eggs, 16% pupae, and 8% adults. The sex ratio over time was approximately 1:1. We conclude with a comparison of our data with previous work on D. suzukii and other Drosophila, and discuss the implications for control and monitoring of this pest.

The biology of the afrotropical Conchyloctenia hybrida Boheman on Solanum campylacanthum subsp. panduriforme was studied under laboratory conditions in South Africa. Papery oothecae contained between 2 and 10 eggs. Adults displayed vigorous feeding, high fertility, longevity, as well as careful choice of oviposition site. Construction of oothecae was highest at the junctions of main and lateral veins on abaxial leaf surfaces facing upwards or downwards and adaxial surfaces facing downwards. The period from oviposition to adult eclosion ranged between 37 and 42 d at 25°C. Adults had an even sex ratio. After a preoviposition period of 34 d, females deposited 3 to 48 oothecae in 4 to 91 d. The mean longevity of females and males was 168 and 165 d, respectively. The net replacement rate was 50.14, the intrinsic rate of natural increase was 0.97 per month, the mean generation time was 4 mo, and doubling time was 0.71 mo. Daily consumption rate of leaves increased rapidly in late larval instars and was highest for adults. Adults underwent a series of elytral color changes corresponding with age and physiological state. Mature adults characterized by hardened metallic-colored elytra had a higher winter survival rate than young adults with soft, nonmetallic elytra.

Successful SIT trials against mosquitoes in the 1960-70s were achieved by sterilizing male mosquitoes using chemosterilants. Their use was discontinued after concerns were raised about the effect of residues on non-target organisms, although scant evidence has been published. Irradiation is an expensive process; chemosterilization could be an affordable option for implementing SIT programs in developing countries. We compare life table parameters of three Aedes aegypti populations comprising different ratios of thiotepa-treated and non-treated males in order to identify the impact on reproductive potential of the presence of sterile males. No difference was observed in the survival of the treated and untreated males. The release of thiotepa sterilized males into caged Ae. aegypti populations had no effect on death or survival probability of the individuals in the cages but the fecundity of females was significantly reduced, as evaluated by hatch rate and stable age structure parameters. The significant decreases in net reproduction rate, finite rate of natural increase and intrinsic rate of natural increase in populations including sterile males are sufficient to indicate that such populations would not be able to proliferate in natural conditions. This suggests that release of Ae. aegypti thiotepa-treated males could be effective in reducing the reproductive capability of the target population and consequently contribute to vector control.

The effect of temperature on the biology and life table of Caloglyphus manuri Eraky & Osman fed on egg masses of the root knot nematode, Meloidogyne sp. was determined at 20, 25 and 30 oC. Its life cycle durated 13.50, 7.92 and 7.42 days for female and 12.65, 7.82 and 7.11 for male when fed at 20, 25 and 30oC, respectively. Female life span averaged 40.70, 28.47 and 24.37 days; while that of male was 29.50, 26.22 and 16.41 days reared. The mean generation time (T) averaged 21.85,1 2.27 and 11.23 days; while the net reproductive rate (R0) value was 106.51, 94.53 and 58.16 at the aforementioned temperature, respectively. The net rate of natural increase (rm) was 0.213, 0.370 and 0.361 individual / ♀ / day, whereas the finite rate of increase (erm) averaged 1.23, 1.44 and 1.43 time / ♀ / day at 20, 25 and 35 oC, respectively.

For decades now, the Republic of Srpska has been affected by the natural depopulation process and starting with 2002 it has been manifested through negative rate of natural increase resulting from natality decrease and mortality increase. During the target period, the number of the live-born declined by 28% whereas the number of the dead increased by 25%. Clearly, negative demographic figures along with negative migrations resulted in the total depopulation. Negative migration balance additionally complicates negative demographic trend, which results in total depopulation of large proportions. Major issue of the Republic of Srpska population is the phenomenon of low fertility resulting from a whole range of negative factors. Therefore, the implementation of population policy measures is fundamental for both society and population in the country.

Problems of urban environmental degradation and inadequacy of housing and basic infrastructural facilities in the Niger Delta cities are well known. The discovery of petroleum oil in the Niger Delta region in the 1950s, is particularly remarkable for very rapid growth of the population of the region, which has increased and greatly intensified problems arising from the inadequacy of urban infrastructural facilities. The rapidity of overall population growth arises from a combination of a high rate of natural increase and a much higher rate of migration. This paper attempts an empirical analysis of slum characteristics in four leading cities in the Niger Delta region, Nigeria. Findings reveal that slum dwellers in these four cities live in subhuman conditionssubstandard dwelling units and protracted lack of community amenities and services. “Upgrading” rather than “clearance”, among others, were recommended for sustainable management of slum areas in the Niger Delta cities in particular and Nigerian cities in general.

Scapsipedus icipe Hugel and Tanga (Orthoptera: Gryllidae) is a newly described edible cricket species. Although, there is substantial interest in mass production of S. icipe for human food and animal feed, no information exists on the impact of temperature on their bionomics. Temperature-dependent development, survival, reproductive and life table parameters of S. icipe was generated and integrated into advanced Insect Life Cycle Modeling software to describe relative S. icipe population increase and spatial spread based on nine constant temperature conditions. We examined model predictions and implications for S. icipe potential distribution in Africa under current and future climate. These regions where entomophagy is widely practiced have distinctly different climates. Our results showed that S. icipe eggs were unable to hatch at 10 and 40°C, while emerged nymphs failed to complete development at 15°C. The developmental time of S. icipe was observed to decrease with increased in temperature. The lowest developmental threshold temperatures estimated using linear regressions was 14.3, 12.67 and 19.12°C and the thermal constants for development were 185.2, 1111.1- and 40.7-degree days (DD) for egg, nymph and pre-adult stages, respectively. The highest total fecundity (3416 individuals/female/generation), intrinsic rate of natural increase (0.075 days), net reproductive rate (1330.8 female/female/generation) and shortest doubling time (9.2 days) was recorded at 30°C. The regions predicted to be suitable by the model suggest that S. icipe is tolerant to a wider range of climatic conditions. Our findings provide for the first-time important information on the impact of temperature on the biology, establishment and spread of S. icipe across the Africa continent. The prospect of edible S. icipe production to become a new sector in food and feed industry is discussed.

This paper attempts to derive model for population projection under gradual change in fertility schedule on stability conditions using birth trajectory at time t for 0 < t ? a . The projected population can be obtained when the data of the rate of natural increase, net reproduction rate, age variance of the net maternity function, birth rate of the initial stable population along with its age distribution are available of the population.Journal of Institute of Science and Technology, 2014, 19(2): 86-88

O artigo apresenta o desenvolvimento, validação e experimentação de um modelo de simulação utilizando a metodologia System Dynamics, a qual permite avaliar e analisar cenários acerca da geração e disposição final dos resíduos sólidos urbanos (RSU). Para tanto, levou-se em consideração: a taxa de crescimento vegetativo populacional (nascimentos e mortes), percentual de resíduo sólido urbano enviado para cada tipo de destino final e a quantidade de resíduos gerada por habitante. A validação do modelo foi através da análise de cenários futuros para um determinado município da região sul do Brasil. Para a modelagem e execução do sistema foi utilizado o software Vensim, da Ventana Systems. Com os resultados gerados pelo modelo de simulação, os gestores da área podem, antecipadamente, discutir, avaliar e decidir possíveis medidas necessárias para melhorias ou adaptações na gestão de resíduos sólidos urbanos. This paper presents the development, validation and application of a simulation model using a systems dynamics methodology, which allows users and managers to evaluate and analyze scenarios in the context of urban solid waste generation and disposal. The developed model accounts for the following rates and parameters: rate of natural increase (birth rates and death rates), percentage of urban solid waste sent to each type of final disposal site and the amount of waste generated per capita. The simulated scenarios consider three distinct situations: (a) the current scenario with varying rates, (b) the current scenario with fixed rates and (c) a scenario with rates similar to those of the Netherlands. The model was validated through the analysis of future scenarios for a municipality in southern Brazil. Vensim- Ventana Systems was employed for the system modeling and development.

a volume of essays on topics in demography honoring Paul demeny would be incomplete without asking why large parts of the european civilization that produced Paul, a gentleman and a scholar in the finest sense of both words, have decided, through the aggregate decisions of women and men, to commit gradual “demographic suicide.” one would think that potential mothers and fathers, facing the promise of peace and relative prosperity, would choose to have children. But, puzzlingly, many people across europe are choosing to have fewer children than will produce stable, much less growing, populations. demography is destiny. the consequences of shifts in fertility (even as moderated or even partially reversed in the future) will have substantial consequences on many aspects of life: aging, health care costs, marital and family relationships, labor markets, immigration, the fiscal sustainability of social insurance programs, and schooling. if anything like the current fertility trends persists, the outcome will have profound consequences for what it means to be a “nation” and what are acceptable social relationships within a nation-state. Current projections of the rate of natural increase imply either unsustainably large reductions in the working-age population or substantially higher levels of the influx of “non-nationals” (or a little of both). the fact that women and men are making choices that result in lifetime childlessness must be symptomatic of a revolution in human affairs. leaving a posterity has, for thousands of years of human history, been an integral part of the very definition of prosperity and happiness for the typical person. those who remained childless—priests and nuns, monks and eunuchs—were recognized as choosing radically different paths to human meaning and happiness or were regarded as unfortunate.

Biological aspects, thermal requirement, predation rate and life table parameters of the phytoseiid predatory mite Euseius scutalis (A.– H.) fed on nymphs of Tetranychus urticae Koch was determined at four temperature degrees, 15, 20, 25 and 30 °C. The total developmental durations of female was correlated negatively with increasing temperature. Minimum developmental thresholds (To) of egg, larva, protonymph, deutonymph, total immature stages and life cycle of E. scutalis female averaged, 4.26, 10.98, 6.90, 1.20, 2.49 and 2.89; respectively. On the other hand E. scutalis female required 208.33 DD to reach adulthood. The net rate of natural increase (rm) was 0.008, 0.126, 0.166 and 0.193, whereas the finite rate of increase (erm) averaged 1.092, 1.134, 1.181 and 1.213 at 15, 20, 25 and 30 o C; respectively.

Impacts of Malthusian positive checks are investigated using data compiled by the United Nations Development Program. We show how the intensity of Malthusian positive checks are correlated with indicators describing the standard of living such as ecological footprint, income per capita, severe poverty, access to pure water and access to sanitation facilities. We then show that mortality increases exponentially with the intensity of Malthusian positive checks (adult mortality, under-five mortality, maternal mortality and deaths by polluted water). However, total fertility rate also increases exponentially. The surprising result of our analysis is that the growth rate and the rate of natural increase are directly proportional to the intensity of Malthusian positive checks. The regenerating impacts triggered by Malthusian positive checks do not just keep the growth undisturbed – they stimulate growth and make it even faster. Using data for Africa, we show that while the death rate increases with the intensity of hunger, total fertility rate, birth rate and the rate of natural increase also increase. Records from China also show that Malthusian positive checks of wars and famines triggered the intensified growth of population. Thus, contrary to the generally promoted interpretations, hunger and famines do not necessarily suppress the growth of population. Similar patterns of stress-induced growth are also observed in nature. This study is closely related to the problem of controlling the growth of human population.Keywords. Malthusian positive checks, Population growth, Income per capita, Birth and death rates, Total fertility rate, Growth rate, Rate of natural increaseJEL. A12, C12, Y80.

This paper uses Logistic model for renewable energy markets under different ownership systems were studied. Logistic model is one of the core theoretical ecology Population Growth Model. According to the market characteristics of renewable energy, our coverage under different ownership system of renewable resources is into the oligopoly market. Through the establishment of a linear dynamic system, the Logistic model was added thereto, analyzed under different ownership systems dynamic Nash equilibrium, and numerical simulation test. Conclusion: (1) Under private ownership, while alive fixation rate of natural increase, the equilibrium point (0,0); endogenous natural growth rate is variable: the overall image offset occurs. In the numerical simulation, changes from 0 to 0.8333, changes from 0 to 1.3333, indicating that in a changing market, the impact of the dynamics of the natural growth rate of renewable resources market equilibrium can not be ignored, and the increase in the number of manufacturer resources sustainable use of both the potential positive effects, may bring negative effects. (2) Under public ownership, within the natural growth rate of raw fixed discount rate of two intersection (2.5,3.1); changes and is declining. In the numerical simulation, from the intersection of (2.5,3.1) down to (1.2,0.7), indicating an increase in the number of manufacturers will give sustainable use of resources brought about negative effects, and when it reaches a certain number, the ecological disaster will be inevitable.

In the article, the theoretical and economic aspects of the category "security" are considered, the distinction between philosophical and socio-economic approaches to the understanding of social security is drawn. From the point of view of the system approach, the place of social security for national security protection is determined. The theoretical content of the category "social security" is shown; in the authors' treatment, the specifying concepts such as "social risks", "danger", "threat" are given. For the purpose of risks identification (deviations) and the revealing of the factors of inefficient financing, the methodological tools for the assessment of the social security of a region are proposed. These tools are based on the integrated assessment of the regional socio-economic indexes and the indexes assessing the budgetary financing of the territory. The methodical approach offered by the authors is based on the detection of dependencies between the social and financial security of a region. As estimates, the indicators reflecting the level of social security in the territory of residence are chosen: income, expenses of the consolidated budget of a region, growth rate of gross regional product, rate of natural population growth, level of unemployment, population share with the income below living level. This approach is approved on the example of Perm Krai and Sverdlovsk region; the regularities, the favourable and adverse periods for social security of the region are revealed. The received estimates are ranged depending on a temporary log of growth (fall), elasticity and sensitivity to the budget financing. The results of the assessment have shown that, from the point of view of social security protection, Perm Krai has entered a stage of deep recession, which started in 2012. Similar tendencies are observed in the Sverdlovsk region. Nevertheless, considering both a visible variety and the dominating influence of Perm Krai and Sverdlovsk region on the social and economic development of the Volga and Ural Federal Districts respectively, the given comparison is of scientific and practical interest. Рассмотрены теоретические и экономические аспекты безопасности региона. Предложен методический инструментарий, который базируется на выявление зависимостей между социальной и финансовой безопасностью. Проанализирована методика оценки социальной безопасности на примере Пермского края и Свердловской области. The research has been supported by the Grant of the Russian Science Foundation (the Project No 14-18-00574 "The information-analytical system "Anticrisis:" diagnostics of the regions, threat assessment and scenario forecasting for the preservation and strengthening of economic security and well-being of Russia).