The Leverage of Demographic Dynamics on Carbon Dioxide Emissions: Does Age Structure Matter?

This article provides a methodological contribution to the study of the effect of changes in population age structure on carbon dioxide (CO₂) emissions. First, I propose a generalization of the IPAT equation to a multisector economy with an age-structured population and discuss the insights that can be obtained in the context of stable population theory. Second, I suggest a statistical model of household consumption as a function of household size and age structure to quantitatively evaluate the extent of economies of scale in consumption of energy-intensive goods, and to estimate age-specific profiles of consumption of energy-intensive goods and of CO₂ emissions. Third, I offer an illustration of the methodologies using data for the United States. The analysis shows that per-capita CO₂ emissions increase with age until the individual is in his or her 60s, and then emissions tend to decrease. Holding everything else constant, the expected change in U.S. population age distribution during the next four decades is likely to have a small, but noticeable, positive impact on CO₂ emissions.     

Preliminary studies on the respiratory energy loss of a spider,Lycosa pseudoannulata

Summary To elucidate the basic food requirement of spiders, the important polyphagous predators of rice-plant insect pests, an attempt was made to measure the respiratory energy loss of fasting spiders,Lycosa pseudoannulata. Relationship between fresh (y) and dry (x) weights of spiders inhabiting the bottom layer of the rice-plant community was represented by the following allometric equation:y=0.428x ^0.872. The carbon dioxide production by previously fed and unfed females under the dark at 29°C 100% R. H. was measured by a titration technique. The relationship between fresh body weight and CO₂ production by unfed animals could be represented by the equationM=aW ^b, M being the CO₂ output per individual per day andW the fresh body weight. The constantb, which determines the slope of curve, was 0.808. Respiration of the adult female with 100 mg fresh weight was 1.155±0.250 mg CO₂/100 g fresh weight/day or 48.69 mg CO₂/g dry weight/day. This value corresponds to 35.81 cal/g fresh weight/day or 150.94 cal/g dry weight/day. Supposing the calorific content of spiders to be 5820 cal/g dry weight, rate of the respiratory energy loss to total energy of the body was estimated to be 2.60%. This rate did not strongly contradict with the loss of fresh body weight before and after the measurement. The metabolic rate showed remarkable fluctuation with changing food supply. The CO₂ production of starved individuals decreased to 83.63±16.34% as compared with individuals which were fed before the measurement.     

Population and global warming with and without CO2 targets

The sensitivity of future global warming to variable population growth rates is reexamined as part of an ongoing debate over the extent to which climate change should be added to the list of concerns surrounding population growth. The UN 1992 low, medium and high population projections out to the year 2150 are run through an integrated climate-economics model which allows the effect of population variability to be traced through to CO₂ emissions, concentrations, warming and economic growth.We treat separately the cases of population's role in global warming, first without and then with specified atmospheric targets. Without targets, modeled CO₂ concentrations in year 2150 show great variability ranging from 600 ppm (UN low projection) to 1375 ppm (UN high projection). Such numbers suggest the potential effect of variable population growth on climate is large and that population policy options carry with them a significant, longterm, global warming mitigation component. The range of global warming achieved is not as sensitive to population because of weakened radiative absorption at high CO₂ levels. With respect to targets, with low population, stabilization at 650–750 ppm is achieved with relatively modest cuts in carbon intensity. Stabilization at 350–450 ppms requires steep cuts in emissions that are only weakly affected by the full range of variable population growth rates. Stabilization at 550 ppm is thus a transitional point between these end-member roles for population. Future work needs to address cost issues which could change this assessment of the role of population with CO₂ targets.     

Decrease in respiratory rate in a wolf spider,Pardosa astrigera (L. Koch), under starvation

Summary Effects of starvation on the suryival period and the respiratory rate in adults of a wolf spider,Pardosa astrigera (L. Koch), were investigated. The spiders used were divided into four groups: well-fed, starved and two limited food groups; in the latter two, each spider was supplied with one leafhopper every second or third day. Adult males and females ofP. astrigera could survive for a long time; 28.8±2.7 days and 54.4±18.9 days, respectively, without any food. The longevities shown here were 73.8% for males and 78.6% for females of those of well-fed spiders, indicating thatP. astrigera adults have a strong tolerance to starvation. The respiratory rate of well-fed adults showed no tendency to increase or decrease with their aging; the mean respiratory rates were 4.86×10⁻⁴ mg CO₂/mg f.w. (fresh body weight)/hr for males and 3.80×10⁻⁴ mg CO₂/mg f.w./hr for females. The respiratory rates of starved spiders increased during the first two days of starvation but decreased markedly from the third to the twelfth day, and thereafter retained an almost constant level for each sex. The mean respiratory rates after the twelfth day of starvation were 2.49×10⁻⁴ mg CO₂/mg f.w./hr for males and 2.76×10⁻⁴ mg CO₂/mg f.w./hr for females; these values were respectively 48.4% and 63.0% of those prior to starvation. The fresh body weight of starved spiders decreased linearly with time but the rate was small. The respiratory rates of the limited food groups tended to decline with time and thereby their weight losses were minimized. The decrease in the respiratory rate under starvation was considered not to be due to spider exhaustion or senescence but due to an intrinsic change in behaviour and/or metabolism, because when the spiders were supplied with ample food for five days after starvation, the respiratory rate and the body weight rapidly recovered to near the levels prior to starvation. It is suggested that starved spiders use a higher ratio of fat as catabolic substrate than normally fed or satiated ones. Feeding strategies of poikilo-therm predators are discussed. This work was partially supported by the Nippon Life Insurance Foundation Research Fund and Grant-in-Aid (No. 56480039) from the Ministry of Education, Science and Culture, Japan.     

Immigration and environmental emissions: A U.S. county-level analysis

This paper investigates the immigration–environment association using U.S. county-level data, for a subset of counties (N = ~200), and a model inspired by the STIRPAT approach. The analysis makes use of U.S. census data for the year 2000 reflecting U.S.-born and foreign-born populations, combined with county-level data reflecting emissions of CO₂, NO₂, PM₁₀, and SO₂. With a focus on approximately 200 primarily urban counties for which complete data are available, and after controlling for income, employment in the utilities and manufacturing sectors, and coal consumption for SO₂ estimations, few statistically significant associations emerge between population composition and emissions. Counties with a relatively larger U.S.-born population have higher NO₂ and SO₂ emissions. On the other hand, counties with a relatively higher number or share of foreign-born residents have lower SO₂ emissions. Although limited to cross-sectional analyses, the results provide a foundation for future longitudinal research on this important and controversial topic.     

On Development,Demography and Climate Change: The End of the World as We Know it?

This paper comments on the issue of global warming and climate change, in an attempt to provide fresh perspective. Essentially, five main arguments are made. First, that the process of modern economic development has been based on the burning of fossil fuels, and that this will continue to apply for the foreseeable future. Second, that in large part due to momentum in economic and demographic processes, it is inevitable that there will be a major rise in atmospheric CO₂ during the present century. Third, that available data on global temperatures suggest strongly that the coming warming will be appreciably faster than anything that humanity has experienced during historical times. Moreover, especially in a system that is being forced, the chance of an abrupt change in climate happening must be rated as fair. Fourth, that while it is impossible to attach precise probabilities to different scenarios, the range of plausible unpleasant climate outcomes seems at least as great as the range of more manageable ones. The consequences of future climate change may be considerable; indeed, they could be almost inconceivable—with several negative changes occurring simultaneously and to cumulative adverse effect. There is an urgent need to improve ways of thinking about what could happen. Fifth, the paper maintains that the human response to other difficult ‘long’ threats—such as that posed by HIV/AIDS—reveals a broadly analogous sequence of social reactions (e.g. denial, avoidance, recrimination) to that which is unfolding with respect to carbon emissions and climate change. Therefore the view expressed here is that major behavioral change to limit world carbon emissions is unlikely in the foreseeable future, and that the broad sway of future events is probably now set to run its course.This paper is a personal assessment of what is occurring with respect to the subject of global warming and climate change. Nevertheless it is an attempt to examine the topic objectively. The paper tries to concentrate on the essentials—from both the social and the environmental sciences—and, quite deliberately, it presents basic data on the subject for the reader's own consideration. The paper's subtitle is taken from a television program broadcast in January 2005 as part of UK Channel Four's War on Terra season. I thank Tim Forsyth, Chris Wilson, and especially Brian O'Neill for their help and advice. However, and most certainly, the usual disclaimer applies.     

Tobacco smoking and the sex mortality differential

This paper examines the effects of tobacco smoking on the sex mortality differential in the United States. It is found that all forms of smoking combined account for about 47 percent of the female-male difference in ₅₀ e ₃₇ (life expectancy between ages 37 and 87) in 1962,and about 75 percent of the increase in the female-male difference in ₅₀ e ₃₇over the period 1910–62. When these percentage effects of smoking are decomposed each into a sum of contributions by age and immediate medical cause of death, the degenerative diseases acting at the older ages are found to be of primary importance. The above results appear in large part to explain why the degenerative diseases also account for most of the 1910–65 increase in the female-male difference in life expectancy at birth. The analysis assumes that spurious effects due to the correlation of tobacco consumption with other mortality-related factors are small compared to the causal effects of tobacco consumption itself.     

The wealth of nations revisited: Income and quality of life

Does economic prosperity enhance the quality of human life? Across 101 nations, 32 indices were analyzed that reflect a representative sample of universal human values (e.g., happiness, social order, and social justice). Wealth correlated significantly with 26 of the 32 indices, indicating a higher QOL in wealthier nations. Only suicide and CO₂ emissions were worse in wealthier societies. Basic physical needs were met early in economic development, whereas advanced scientific work occurred only when basic physical needs were fulfilled for almost all people in the society. Limitations of the conclusions are discussed.     

Nutritional contribution to females of14C-labeled male secretions transferred during mating inMenida scotti (Heteroptera: Pentatomidae)

Menida scotti (Puton) males have been shown to transfer secretions from their bulbus ejaculatorius and reservoir of ectodermal accessory gland to females by mating during hibernation. In the present study, the major components of the secretions were found to be proteins and lipids. To specify the female organ incorporating the male secretions, a radiotracer experiment in which the male secretions were labeled by [¹⁴C]valine was conducted in nine tissues of females collected in the fall and spring of the hibernation period. Relatively high radioactivities were detected in the haemolymph and the residual carcass (head, legs, air-sacs, exoskeleton, etc.) in the fall females, and in CO₂ gas evolved and carcasses in the spring females. The radioactivities in the fat body were significantly higher in the fall mating females than in the spring mating females, and vice versa in the ovary. The radioactivities in six fractions (lipids, proteins, glycogen, sugars, free amino acids and the residues) were also assayed in the five organs of females that had a relatively high radioactivity. The highest radioactivity was detected in the protein fraction of the haemolymph in fall and spring females. There were significant differences in the radioactivities incorporated into the lipid fractions of the carcass between fall and spring females.     

Energy, population and the environment: exploring Canada’s record on CO2 emissions and energy use relative to other OECD countries

Across the OECD, Canada??s record on CO₂ emissions is particularly poor, with overall emissions up 32% over the 1990?C2007 period. The current paper seeks to better understand this situation by making systematic comparisons of Canada with other OECD countries. For Canada overall, the rapid increase in emissions over the 1990?C2007 period can be explained by several factors, including major population growth, increased affluence (although to a lesser extent than elsewhere in the OECD), a continued dependence on fossil fuels, while continuing to increase its overall demand for energy. While the energy intensity of Canada??s economy has declined somewhat over recent years, it actually lagged behind most OECD countries on this front and remains one of the most energy intense economies in the world (2nd highest in the OECD on our indicator of energy intensity). While there are many factors responsible for this, Canada??s particularly energy-intensive industrial structure is certainly relevant, as is the importance of its primary sector relative to most developed nations.     

Measuring Attitudes About Intimate Partner Violence Against Women: The ATT-IPV Scale

In lower-income settings, women more often than men justify intimate partner violence (IPV). Yet, the role of measurement invariance across gender is unstudied. We developed the ATT-IPV scale to measure attitudes about physical violence against wives in 1,055 married men and women ages 18–50 in My Hao district, Vietnam. Across 10 items about transgressions of the wife, women more often than men agreed that a man had good reason to hit his wife (3 % to 92 %; 0 % to 67 %). In random split-half samples, one-factor exploratory factor analysis (EFA) (N ₁ = 527) and confirmatory factor analysis (CFA) (N ₂ = 528) models for nine items with sufficient variability had significant loadings (0.575–0.883; 0.502–0.897) and good fit (RMSEA = 0.068, 0.048; CFI = 0.951, 0.978, TLI = 0.935, 0.970). Three items had significant uniform differential item functioning (DIF) by gender, and adjustment for DIF revealed that measurement noninvariance was partially masking men’s lower propensity than women to justify IPV. A CFA model for the six items without DIF had excellent fit (RMSEA = 0.019, CFI = 0.994, TLI = 0.991) and an attitudinal gender gap similar to the DIF-adjusted nine-item model, suggesting that the six-item scale reliably measures attitudes about IPV across gender. Researchers should validate the scale in urban Vietnam and elsewhere and decompose DIF-adjusted gender attitudinal gaps.     

Competitive exclusion through reproductive interference

Summary A simple differential equation model was developed to describe the competitive interaction that may occur between species through reproductive interference. The model has the form comparable to Volterra's competition equations, and the graphical analysis of the outcome of the two-species interaction based on its zero-growth isoclines proved that: (1) The possible outcome in this model, as in usual models of resource competition, is either stable coexistence of both species or gradual exclusion of one species by the other, depending critically upon the values of the activity overlapping coefficientc _ij ; (2) but, for the samec _ij -values, competitive exclusion is much more ready to occur here than in resource competition; (3) and moreover, the final result of the competition is always dependent on the initial-condition due to its non-linear isoclines, i.e., even under the parameter condition that generally allows both species to coexist, an extreme bias in intial density to one species can readily cause subsequent complete exclusion of its counterparts. Thus, it may follow that the reproductive interference is likely to be working in nature as an efficient mechanism to bring about habitat partitioning in either time or space between some closely related species in insect communities, even though they inhabit heterogeneous habitats where resource competition rarely occurs so that they could otherwise attain steady coexistence.     

Life table technique for the working ages

Some results of efforts to design an integrated formula system for age-specific death rates, survivals and expectation of life are presented. The report deals only with the active ages 15–80. The system is based on the assumption that the age-specific central mortality rate (m _x ) can be expressed satisfactorily by means of a polynomial m = a ₀ + a ₁ x + a ₂ x ²+ ….     

Causal Ordering of Basic Psychological Needs and Well-Being

What is the relationship between well-being and satisfaction of basic psychological needs overtime? The basic psychological needs theory is a subtheory of the self-determination theory that elaborates the concept of psychological needs and its relations to psychological health and well-being. The goals of this research was to establish the causal ordering between basic psychological needs and three psychological well-being indicators (subjective well-being, self-esteem and satisfaction with life), in a longitudinal study. We used a cross-lagged two-wave design. A total of 272 university students completed the questionnaire at the beginning and at the end of the semester. Relatedness at time 1 (T₁) had a positive and significant effect on all well-being indicators at time 2 (T₂); competence (T₁) had a positive and significant effect on all indicators except for self-esteem (T₂); finally, autonomy (T₁) did not have a significant effect on any of the well-being indicators (T₂). In conclusion, we confirm the causal ordering of competence and relatedness on well-being, according to the basic psychological needs subtheory. Universities, in general, and teachers, in particular, should promote relations between students and support the need of competence.     

Some extensions of the keyfitz momentum relationship

A stable population, such that the total birthrateB(t) =B _o e ^ro^t, is abruptly altered by modifying the age-specific birth rate,m(x). The survivor function remains unaltered. The modified population ultimately settles down to a stable behavior, such thatB(t) =B ₁ e ^r ₁ ^t . It is shown thatB ₁/B ₀ = (R ₀ ?R ₁)/[(r ₀ ?r ₁)R ₀ Z ₁], whereR ₀,R ₁ are the net reproduction rates before and after the change, and \(\bar Z_1 \) expected age giving birth for the stable population after the change. The age structure and transients resulting from the change are also described. The effect of an abrupt change in the survivor functionl(x) is also investigated for the simple case where the change is caused by alteringl(x) toe ^?λx l(x). It is shown that the above ratio becomes \(B_1 /B_0 = N_1 /N_0 = [1 - \smallint _0^\infty e^{ - kx} g(x)dx]/\bar Z_1 \lambda \) , whereN refers to the numbers in the population,k =r ₀ + λ, andg(x) =m(x)l(x), the value before the change. A measure for the reproductive worth of the population is also established.     

Sex-Structured Dynamic of Multi-Group Herpes Simplex Virus 2

A 3(n + l)-dimensional ordinary differential equation for HSV-2 includes l groups of men and n groups of women with different risks of infection. Global Lyapunov functions based on graph theory and on LaSalle invariance principle show that the model dynamics are completely determined by the basic reproduction number ?₀. The disease-free equilibrium is globally asymptotically stable when ?₀ ≤ 1; a unique endemic equilibrium is globally asymptotically stable in the interior of the feasible region when ?₀ > 1.     

Deme formation in gall-making aphidsAdelges japonicus (Homoptera: Adelgidae)

The deme formation hypothesis in herbivorous insects states that herbivores differentiate genetically into small demes, each specialized in the idiosyncratic traits of individual plants. We examined this hypothesis in gall-forming aphids,Adelges japonicus, by reciprocal transfers of aphids among three susceptible clones ofPicea jezoensis standing in proximity. Performance of aphids transferred to their natal clone was compared with that of aphids transferred to other novel clones. ANCOVA showed no significant donor (source of aphids) by receptor (recipient of aphids) interactions for both total aphid performance on the host tree over a life cycle and its three subdivisions(q ₁,q ₂ andq ₃). In addition, the total performance on the natal clone was lowest among those in the three clones, which was explicitly against the prediction from the local adaptation. In contrast, there were significant receptor effects onq ₁ (fecundity of gallicolae multiplied by survivorship of fundatrices while feeding on needles) andq ₃ (fecundity of fundatrices multiplied by survivorship of gallicolae before emergence from the galls), suggesting genetic differences in resistance among clones. The two-fold difference inq ₃ among clones was due to different gall size, which was highly correlated with the number of gallicolae that emerged from the gall. The two-fold difference inq ₁ seemed to be caused by different survivorship of larval fundatrices while feeding on needles.     

Are the affluent prepared to pay for the planet? Explaining willingness to pay for public and quasi-private environmental goods in Switzerland

A large number of ‘environmental justice’ studies show that wealthier people are less affected by environmental burdens and also consume more resources than poorer people. Given this double inequity, we ask, to what extent are affluent people prepared to pay to protect the environment? The analyses are couched within the compensation/affluence hypothesis, which states that wealthier persons are able to spend more for environmental protection than their poorer counterparts. Further, we take into account various competing economic, psychological and sociological determinants of individuals’ willingness to pay (WTP) for both public environmental goods (e.g., general environmental protection) and quasi-private environmental goods (e.g., CO₂-neutral cars). Such a comprehensive approach contrasts with most other studies in this field that focus on a limited number of determinants and goods. Multivariate analyses are based on a general population survey in Switzerland (N = 3,369). Although income has a positive and significant effect on WTP supporting the compensation hypothesis, determinants such as generalized interpersonal trust that is assumed to be positively associated with civic engagement and environmental concern prove to be equally important. Moreover, we demonstrate for the first time that time preferences can considerably influence survey-based WTP for environmental goods; since investments in the environment typically pay off in the distant future, persons with a high subjective discount rate are less likely to commit.     

A probabilistic interpretation of the United Nations’ 1995–2005 population projections

I develop probabilistic interpretations for the United Nations’ 10-year population forecasts by comparing 1995 projections for 212 countries to the population sizes reported for 2005. Errors in the estimation of the intrinsic rate of increase, presumably caused by erroneous assumptions about birth, death and/or immigration rates, appear to be more consequential than errors based on inaccurate estimation of the starting, or ‘jump-off’, population size. For only about 20% of the countries did the ‘actual’ 2005 population size fall between the United Nations’ low- and high-variant projections. I propose prediction intervals for country-specific population sizes 10 years in the future of the form [ N_i^￠ (t+10) / k ,  k ·N_i^￠ (t+10) ],[ N_i^{\prime} (t+10) / k , \, k \cdot N_i^{\prime} (t+10) ], where N _i ′(t + 10) is the medium-variant prediction for year t + 10 made in year t, and k is a number that varies with starting population size. Based on the 1995–2005 United Nations’ data, values of k giving 95% coverage range from 1.11 for countries with a population on the order of 10⁹, to 1.45 for countries with a population of 10⁵.     

Workers, workers’ productivity and the dependency ratio in Germany: analysis with implications for social policy

Retirement is an inevitable rite of passage. Retirees draw income from savings, pensions, and perhaps benefits from state welfare systems. Their economically productive years behind them, older workers become an important component in an interesting social indicator—the dependency ratio, (D _r). The D _r measures not only the social significance the elderly have in society, but also the potential economic burden placed on productive workers. Problems may arise that ratchet up the dependency ratio and create important policy dilemmas. In Germany, a larger and increasing D _r points toward future social problems. The dependency ratio is an aggregate measure that masks a considerable amount of variation. Two issues related to the dependency ratio have not been addressed at length. The dependency ratio is related to the labor force via the denominator; it might be important to recognize that certain segments of the labor force are disproportionately burdened. Identifying those segments of workers can better inform decision makers about what policies to implement in addressing the dilemmas reflected in a high dependency ratio. The dependency ratio is also related to worker productivity—the greater the worker productivity, the less of an issue is the dependency ratio, regardless of its size. At bottom, the issue is whether those in the labor force are able to support the retired population. This paper examines the relationships between workers, productivity, and the dependency ratio. It concludes by providing some policy recommendations.