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1.
October 5,the ninth day of the ninth lunar month,was the day of the traditional Double Ninth Festival.Sanshui District of Foshan City in Guangdong organized a 1000-old-men feast that day.More than 1000 local senior citizens joined a series of activities during the Cultural Festival of Longevity.During the feast,Guangdong Committee on Ageing told our reporter that Guangdong would establish the old-age allowance (OAA) system throughout the province by 2015. 相似文献
2.
Population and Environment - 相似文献
3.
基于新陈代谢GM(1,1)模型的重庆市人口老龄化预测研究 总被引:2,自引:0,他引:2
重庆市老龄化率居全国之首,老年人口数继续呈上升趋势,解决养老问题,发展养老产业势在必行。文章对重庆市65岁及以上老年人口数进行预测,通过GM(1,1)基础模型和新陈代谢GM(1,1)模型,在充分考虑扰动因素和驱动因素等新信息影响的基础上,借助Matlab软件编程计算和检验,对重庆市2015~2020年65岁及以上老年人口进行预测。预测结果表明:2015~2020年间重庆市65岁及以上老年人口数不断增长,2020年将突破400万人,说明重庆未来养老形势异常严峻,并对此针对性提出对策建议。模型精度检验表明模型精度为一级,模型预测结果可靠性高、可信度强,模型适合人口中长期预测。 相似文献
4.
Following four hypotheses on the production of soldiers were tested in thePheidole fervida colonies collected in the natural field:
The present test suggested that the last idea was most likely to the wild colonies ofP. fervida. 相似文献
1. | The proportion of new soldiers is primarily dependent on the population size of old workers. |
2. | The abundance of old soldiers reduces the proportion of new soldiers. |
3. | The production of sexuals reduces the proportion of new soldiers. |
4. | The number of soldiers is correlated with the size of defense zone. |
5.
Jan Eichhorn 《Social indicators research》2014,119(1):389-404
A negative effect of unemployment on subjective well-being has been demonstrated in many studies casting substantial doubt about assumptions of decisions of individuals to choose unemployment voluntarily as the utility-maximising option. These studies have been extended to take into account national-level context factors which have been shown to moderate the relationship between unemployment and life-satisfaction. So far most studies focussed mainly on economic indicators, although demographic and cultural differences between countries also affect how unemployment is perceived. An important variable that is not included in the majority of proper multilevel studies is the extent of unemployment benefits. Traditional micro-economic approaches argue that more extensive provisions should reduce the cost of unemployment and therefore reduce the motivation to regain employment—reflected in a reduction of the negative impact of unemployment. This study investigates this claim by using European Values Study data from all European Union countries and Norway as well as harmonised macroeconomic statistics from Eurostat. It finds that the effect of unemployment on life-satisfaction is indeed moderated by economic and demographic national-level factors, but not by unemployment benefits. To what extent unemployment reduces life-satisfaction varies greatly between countries, but appears to not be influenced by the extent of state unemployment provisions. 相似文献
6.
Summary The population dynamics of an epilachnine beetle, which is closely related toEpilachna sparsa
Dieke (henceforth called “sp. C”) and feeds on bitter cucumberMomordica charantia, was studied by mark-recapture of adults and the construction of life tables. The study was repeated three times, i.e., March–May,
July–September and October–December in 1982, in Padang, Sumatra, Indonesia. After the establishment of the host plants, adults
of “sp. C” soon colonized, and each study period ended in the death of the plants due to defoliation by the larvae and adults.
The estimated mean length of residence of adults ranged from 6–11 days, but this was probably much shorter than the actual
longevity, because the adults were so active that they flew away, or dropped off the plants, when they were approached or
slightly disturbed. Life tables indicated that egg mortality ranged from 17.8–53.9%, and a parasitic waspTetrastichus sp. B made up 41.1–64.2% of egg mortality. Two wasps,Tetrastichus sp. C andPediobius foveolatus killed 1.2–19.4% (7.6–100%)* of 4th instars and only the latter species attacked the pupae, killing 24.6–59.1% (45.1–72.4%). Parasitism and starvation
by overcrowding contributed most to the total mortality from egg to adult emergence, which ranged from 89.4–99.5%. “Sp. C”
had a higher diversity and level of parasitism than the Japanese species,E. vigintioctopunctata. The high dispersal power of “sp. C”, coupled with the prolongedl
x−mx schedules shown under laboratory conditions, was advantageous for exploiting the food plant which was available throughout
the year, but was rather patchily distributed in space. 相似文献
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Summary Field populations of blue alfalfa aphid and pea aphid on alfalfa were sampled during 1985 and 1986 to determine the association
of co-occurrence, interspecific interactions and comparative temporal variations in the spatial dispersion patterns of these
species in Oklahoma. Relative abundance of these species is discussed in the light of above analyses.Cole's coefficient revealed a high degree of association between these species in terms of their occurrence on the same alfalfa
stems in the field. Regression analyses indicated that the species populations tended to increase in concert on the same stems
without evidence of competitive displacement. Spatial dispersion patterns of both species were highly aggregated at low population
densities early in the season. Over time, both species tended to disperse and became less aggregated as numbers increased.
It was concluded that magnitude of interspecific interactions between the blue alfalfa aphid and the pea aphid were not of
a nature that they could be termed as competing species. On the contrary, a concept of an “ecospecies” is proposed for practical
applications such as sampling plans and economic threshold determinations. 相似文献
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11.
Demographic crisis: The impact of the Bangladesh civil war (1971) on births and deaths in a rural area of Bangladesh 总被引:1,自引:0,他引:1
Summary In Matlab Bazaar Thana the Cholera Research Laboratory has registered the births, deaths and migrations in a population of approximately 125,000 since 1966. Although this rural area was not the scene of any significant armed encounters, striking changes in birth and death rates were registered during and after the conflict. Birth rates did not change during the relatively brief period of the civil war, but a small decline was registered for one year after the war. Fertility rates which had been declining slightly and irregularly in the pre-war baseline period may have increased slightly during the war and fell substantially in all age groups in the year following the war. The crude death rate, which rose by 37 per cent during the war, was a very sensitive reflection of the administrative and economic problems. Overall infant mortality rose by only 15 per cent over pre-war levels because all of the increase was observed in the post-neo-natal component, which traditionally accounts for less than one-third of the total infant mortality in Bangladesh. Children and older adults accounted for the majority of excess deaths which were largely attributed to acute diarrhoeas and other gastro-intestinal causes. The death rate at ages 1-4 rose by 43 per cent and at ages 5-9 soared to 208 per cent above pre-war baseline rates. All increases in age-specific mortality rates fell to baseline levels during the year following the war, except the 5-9-year age group, in which rates continued to be high largely because of deaths due to dysentery. 相似文献
12.
Samples of shoots ofPistacia lentiscus carrying galls of the aphid,Aploneura lentisci, were collected at three localities in Israel.
Shoots growing near pruning scars carried more galls than elsewhere on the plant, but these galls weighed less and contained
fewer aphids (smaller clones). The proportion of empty galls increased with gall density. Crowding of galls at such sites
may be due to the early burst of buds at the time of aphid emergence from the overwintering eggs, and not to active search
for preferred sites. 相似文献
13.
Naoya Osawa 《Researches on Population Ecology》1989,31(1):153-160
Summary Sibling (cannibalism among siblings) and non-sibling cannibalism (cannibalism among non-siblings) were studied in a natural
population of a lady beetle,Harmonia axyridis
Pallas.
Of all the eggs laid (n=2269), 24.76% (n=562) were killed by sibling cannibalism and 36.10% (n=819) were killed by non-sibling cannibalism. Sibling cannibalism occurred constantly and intensively in most egg batches
throughout the entire oviposition period. On the other hand, non-sibling cannibalism was more intense in the middle and late
oviposition periods, and when the egg batches were close to an aphid colony. This may be due to the high density ofH. axyridis larvae relative to aphid density in the middle and late oviposition periods and also the larvae searching intensively near
an aphid colony. 相似文献
14.
The Anamnestic Comparative Self Assessment (ACSA) measure of subjective well-being (SWB) aims to reduce the problems of cultural
bias and relativity to external standards by allowing people to define the endpoints or ‘anchors’ of the measurement scale.
In medical terminology anamnestic denotes ‘based on memory’. The ACSA uses subjects’ memories of the best and worst periods
in their lives to define the anchors of the scale. They then assess their current quality of life relative to these personal
anchors. The South African pilot study tested the match between self-assessment of SWB with ACSA and the conventional single-item
measures of life satisfaction and happiness used in the South African Quality of Life Trends Study and analysed the narratives
of the best and worst times of life. The quota sample of 46 consisted of 26 residents of Makana district in the Eastern Cape
Province, South Africa, and 20 patients undergoing treatment in the local TB hospital. Mean SWB ratings with all three measures
of life satisfaction, happiness and ACSA were between 5 and 6 on a 0–10-point scale. Ratings on all three scales were positively
correlated. However, on ACSA the TB patients rated their current SWB 1.84 points lower than the community respondents, suggesting
a greater sensitivity of this measure. It was observed that the starting points of the life stories produced by respondents
to define the anchor periods for ACSA were related to their current assessment of SWB. A typology was developed that combined
the starting point of the life stories with current SWB. The majority of community respondents matched the ‘Achiever’ type
who scored positively on ACSA (i.e., above the mid-point of the scale) and whose life stories started with the worst period
of their lives and proceeded to the best period. The TB patients were the only respondents to represent the ‘Survivor’ type
whose morale had recovered after misfortune in life. ‘Survivors’ started their narratives with the best period in their lives,
then moved to the worst (often health-related) one, and gave positive ACSA ratings. Based on the qualitative analysis of narratives,
it is concluded that ACSA is a sensitive measurement instrument and therefore particularly useful for monitoring the effects
of treatments and social interventions in longitudinal studies. However, further research is required to verify its cross-cultural
validity.
相似文献
Jan BernheimEmail: |
15.
本文采用地理信息系统(GIS)的空间分析技术,利用地理信息系统分析软件(ARCView GIS)、探索性空间分析技术软件(GeoDA)、社会科学统计软件包(SPSS)等软件,对1982年、1990年和2000年三次全国人口普查的县域截面数据进行了分析。通过空间分析,识别出我国高出生性别比聚集的热点区域,并进一步对其分布、演变特点和成因进行了较深入研究,试图找到热点区域分布及变化的规律性特点。在此基础上,提出了热点区治理和跨区域治理相结合的政策思路。 相似文献
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The contributors to this discussion were invited to submit comments, each from a different standpoint, on the paper by John Caldwell and Thomas Schindlmayr that appeared in the preceding issue of the journal. The invitation was issued with the approval of these authors, and the journal is grateful to them for allowing their paper to be used to generate debate on the issues they had raised. The discussion is followed by the authors' response to it. 相似文献
18.
本文选取1996—2011年我国的省际面板数据,利用动态面板数据模型广义矩(GMM)分析方法,对 FDI 对我国就业影响的动态效应与区域差异进行了实证分析.研究结果发现,FDI 对我国就业影响的区域差异显著,整体上具有显著的挤出效应;仅滞后1期 FDI 对中部地区当年就业的创造效应显著,而其他时域的 FDI 对当年就业的影响均是负向的.因此,引进 FDI 无法吸纳更多的劳动力,依靠 FDI 很难缓解国内的就业压力. 相似文献
19.
This paper describes the conceptual development of a self-enumerated scale of quality of life (CASP-19) and presents an empirical
evaluation of its structure using a combination of exploratory and confirmatory factor analytic approaches across three different
survey settings for older people living in England and Wales in the new millennium. All evaluations are conducted using MPlus
which allows the analyst to evaluate the properties of the scale for a set of multivariate categorical items which are subject
to item non-response. CASP-19 is a subjective measure of well-being derived from an explicit theory of human need spanning
four life domains: control, autonomy, self-realisation and pleasure. Put formally, CASP-19 is a self-reported summative index
consisting of 19 Likert scale items. The three survey settings include a postal survey of 263 people in early old age followed
up from childhood when the respondents were first interviewed in the 1930's, the first wave (2002) of the English Longitudinal
Study of Ageing (ELSA_1) and the eleventh wave of the British Household Panel Survey (BHPS_11) also conducted in 2002. These
nationally representative surveys consisted of 9300 and 6471 respondents aged 55 years and older. The Boyd-Orr sample provides
an exploratory context for the evaluation and ELSA_1 together with BHPS_11 provide the opportunity for confirmatory analyses
of three measurement models. There is some support for the use of CASP-19 as a stand alone summative index. However, the analysis
reveals that a shortened 12-item scale which combines the life domains 'control and autonomy' in a second order measurement
model is the recommended model for analysts. The work was funded under the UK's Economic and Social Research Council's Growing
Older Programme and their Priority Network on Human Capability and Resilience. Grant Nos. L480254016 & L326253061.
相似文献
R. D. WigginsEmail: |
20.
Shefali Begum Ritsuko Tsukuda Kenji Fujisaki Fusao Nakasuji 《Researches on Population Ecology》1996,38(2):257-263
The wild crucifers,Rorippa indica andLepidium virginicum, are known to serve as host plants for the diamondback moth (DBM),Plutella xylostella, but they are less suitable than the preferred cultivated cruciferous plant, cabbage, in terms of adult body size and fecundity.
The life history traits and flight activity of DBM adults grown on various host plants were investigated. The adults thus
reared on each host plant were divided into three size groups (small, medium and large). In general, female adults grown on
the wild crucifers were less fecund and lived longer than those reared on cabbage. Flight activity was higher in adults grown
on wild crucifers than in those reared on cabbage. Male adults flew longer than females. Fecundity, longevity, flight activity
and morphometrical characters of adults were positively correlated with pupal weight in individuals reared on the same host
plant. A negative relationship was found between fecundity and flight activity in females of the same size group, but a positive
one was observed in females reared on the same host plant. 相似文献