Human capital, schooling and health

A consensus has been forged in the last decade that recent periods of sustained growth in total factor productivity and reduced poverty are closely associated with improvements in a population's child nutrition, adult health, and schooling, particularly in low-income countries. Estimates of the productive returns from these three forms of human capital investment are nonetheless qualified by a number of limitations in our data and analytical methods. This paper reviews the problems that occupy researchers in this field and summarizes accumulating evidence of empirical regularities. Social experiments must be designed to assess how randomized policy interventions motivate families and individuals to invest in human capital, and then measure the changed wage opportunities of those who have been induced to make these investments. Statistical estimation of wage functions that seek to represent the relationship between wage rates and a variety of human capital stocks may yield biased estimates of private rates of return from these investments for a variety of reasons. The paper summarizes several of these problems and illustrates how data and statistical methods can be used to deal with some of them. The measures of labor productivity and the proxies specified for schooling and adult health are first discussed, and then the functional relationships between human capital and wages are described. Three types of estimation problem are discussed: (1) bias due to omitted variables, such as ability or frailty; (2) bias due to the measurement of an aggregation of multiple sources of human capital, e.g. genetic and socially reproducible variation, which may contribute to different gains in worker productivity; and (3) errors in measurement of the human capital stocks. Empirical examples and illustrative estimates are surveyed.     

Solvent proton relaxation of aqueous solutions of the serum proteins alpha 2-macroglobulin, fibrinogen, and albumin.

The longitudinal, transverse, and spin-locked rotating frame relaxation rates have been measured for water protons in aqueous solutions of the human serum proteins albumin, fibrinogen, and alpha 2-macroglobulin in the physiological concentration range below 50 g/liter, corresponding to an upper limit for molarity of 725, 147, and 69 microM, respectively. The linear concentration dependence of all the relaxation rates measured at 100 MHz was used to provide the molar sensitivities of each relaxation process for each of the protein solutes. Both the solute dependence and the relaxation-process dependence of the molar sensitivities have been analyzed in terms of a model that has emerged from previous R1 dispersion measurements. This analysis demonstrates consistency between our data and that model for the active motions and their motional rates.     

The effects of ultraviolet irradiation on a coccoid blue-green alga: survival, photosynthesis, and photoreactivation

The effects of UV irradiation (254 mμ) on a coccoid blue-green alga Agmenellum quadruplicatum, Strain PR-6, have been examined in terms of the survival curve and measurement of short time photosynthetic rates. From study of survival evidence has been found for a strong photoreactivation centered near 430 mμ. Measurements of photosynthetic rate suggest that there is a correlation between decay of photosynthesis and survival after UV exposure. The UV induced decay in photosynthetic activity is reversed by the identical photoreactivation conditions that increase the survival level. The photosynthetic data are interpreted as demonstrating a photoreactivation of photosynthesis in blue-green algae.     

Short-term versus long-term effects of food intake on reproductive output in a viviparous snake, Vipera aspis

Feeding rates influence reproductive output in many kinds of animals, but we need to understand the timescale of this influence before we can compare reproductive energy allocation to energy intake. A central issue is the extent to which reproduction is fuelled by long-term energy stores ("capital" breeding) versus recently-acquired resources ("income" breeding). Our data on free-living aspic vipers show that there is no simple answer to this question: reproductive frequency is determined by long-term energy stores, offspring size is influenced by maternal food intake immediately before ovulation, and litter size is influenced by both long-term stores and short-term energy acquisition. Thus, offspring size in free-living vipers reflects the mother's energy balance over the preceding year (via a trade-off between litter size and offspring size) as well as her energy balance in the current breeding season. Hence, different components of a given reproductive output (litter) are not only functionally linked, but also respond to different temporal scales of prey availability. A female's body size has little effect on her reproductive output. Attempts to quantify reproductive energy allocation must take into account the fact that different reproductive traits (such as offspring size versus number) may respond to energy availability over different timespans. Thus, although the aspic viper is a typical "capital breeder" in terms of its reliance on stored reserves for maternal "decisions" concerning reproductive frequency, it is to some degree a facultative "income breeder" with respect to the determination of offspring size and litter size.     

基于改进三维生态足迹的沈阳市自然资本动态

利用改进后的三维生态足迹模型,对沈阳市1995—2014年自然资本动态变化趋势进行分析.结果表明: 1995—2014年,沈阳市人均生态承载力整体呈小幅波动,人均生态足迹、人均生态赤字、人均足迹广度和足迹深度整体上呈波动式增加;足迹广度和足迹深度的变化率逐渐趋向稳定;耕地自然资本利用从2004年开始由资本流量过渡为资本存量,资本存量取代资本流量成为区域耕地自然资源需要的来源,且存量流量利用比逐渐增大;林地一直在利用资本流量,资本流量占用率基本保持不变;草地和水域一直在利用资本存量,且存量流量利用比逐渐增大;沈阳市的发展处于不可持续状态.协调好自然资本存量消耗与存量流量利用之间的关系是实现沈阳市可持续发展的关键途径之一.可通过开发新能源、合理规划土地和提高土地利用率来减少对自然资本的消耗,同时加强对生态环境的保护,以实现沈阳市的可持续发展.     

Wealth as a source of density dependence in human population growth

In modern industrialized countries, human birth rates have been declining persistently for decades. In many cases they have now fallen below the replacement threshold. However, unlike in natural populations where population growth is constrained by limited resources, birth rates in modern industrialized countries are negatively correlated with resource availability. Here, declining birth rates in human populations are shown to be a manifestation of density‐dependent population growth brought on by socioeconomic development. This is demonstrated by combining empirical power law relations between population size, gross domestic product (GDP) per capita, and fertility in a simple theoretical model describing population dynamics in developed countries. For a closed population, the model exhibits growth to a globally stable equilibrium population size, for both national and city populations. A version of the model that is open with respect to immigration and the influence of foreign technology and capital exhibits a good fit to long‐term time series data on population size, GDP per capita, and birth rates for the United States, France and Japan.     

Social Capital, Narratives of Fragmentation, and Schizophrenia: An Ethnographic Exploration of Factors Shaping African-Caribbeans’ Social Capital and Mental Health in a North London Community

Recent research studies have proposed the concept of social capital—broadly defined as social networks, community cohesion, and participation—as a social risk factor for health disparities and the high rates of schizophrenia among individuals of Caribbean heritage in England. However, many of the existing studies lack sociohistorical contexts and do not capture the experiential dimensions of individuals’ social capital. This paper adds to the debate by examining the mechanisms and sociocultural processes that shape the understandings and experiences of social capital in a sample of British African-Caribbeans. Drawing on ethnographic and survey data collected over 2 years in a North London community, the paper focuses on participants’ every day experiences and the stories they tell about their community and social fragmentation. These stories suggest that social changes and historical forces interact to affect the social capital and emotional well-being of local African-Caribbean residents. I argue that my participants’ collective narratives about their social environment contribute to the emotional tone of the community, and create added stressors that may impact their mental health.     

Impact of body reserves on energy expenditure, water flux, and mating success in breeding male northern elephant seals

In capital breeders, individual differences in body size and condition can impact mating effort and success. In addition to the collateral advantages of large body size in competition, large nutrient reserves may offer advantages in endurance rivalry and enable the high rates of energy expenditure associated with mating success. We examined the impacts of body reserves and dominance rank on energy expenditure, water flux, mating success, and breeding tenure in the adult male northern elephant seal, a polygynous, capital breeder. Adult males expended energy at a rate of 159 ± 49 MJ d (-1), which is equivalent to 3.1 times the standard metabolic rate predicted by Kleiber's equation. Despite high rates of energy expenditure and a long fasting duration, males spared lean tissue effectively, deriving a mean of 7% of their metabolism from protein catabolism. Body composition had a strong impact on the ability to spare lean tissue during breeding. When controlling for body size, energy expenditure, depletion of blubber reserves, and water efflux were significantly greater in alpha males than in subordinate males. Large body size was associated with increased reproductive effort, tenure on shore, dominance rank, and reproductive success. Terrestrial locomotion and topography appeared to strongly influence energy expenditure. Comparisons with conspecific females suggest greater total seasonal reproductive effort in male northern elephant seals when controlling for the effects of body mass. In polygynous capital breeding systems, male effort may be strongly influenced by physiological state and exceed that of females.     

An allometric method for the projection of eelgrass leaf biomass production rates

We demonstrate that an allometric model for eelgrass leaf-growth rates can be derived from data on leaf architecture and growth form. Using this construct, we produced indirect assessments of growth rates of leaves that we call projections, which can be easily obtained in terms of allometric parameters and proxy values for leaf area, expressed as the product of leaf length and width. These projections of leaf-growth rates displayed a high level of correspondence with values observed in our data, as well as with other sets of reference data. A comparison with growth rates obtained by using the plastochrone index method showed that our model provides more accurate estimations while using a simpler methodology. Our results also show that whenever allometric parameters for the scaling of eelgrass leaf dry weight in terms of leaf area are available, the proposed model provides an accurate, cost-effective and non-destructive alternative to assessments based on traditional or plastochrone methods.     

Are Kirindy sifaka capital or income breeders? It depends

The capital and income breeding framework has only recently been used to explain variation in female reproductive strategies in primates. The application of this framework to primates and other mammals with long reproductive cycles has not been consistent. We evaluated data on Verreaux's sifaka (Propithecus verreauxi verreauxi) in the Kirindy Forest of western Madagascar to determine whether they are capital or income breeders. We found that Verreaux's sifaka can be classified as either capital or income breeders, depending on how these concepts are operationalized. These conflicting findings highlight why the capital/income framework is currently problematic and must be standardized if it is to be a useful framework for primatologists.     

Productivity,obesity, and human capital: Panel data evidence

The consequences of obesity for adults and children are well documented in the extant literature. We use panel data of 105 countries from 1990 to 2019 to estimate the effect of obesity on economic performance. We predict obesity using lagged values of child obesity as instruments. Predicted obesity has a negative and significant effect on productivity. This effect is independent of the effect of human capital and other macroeconomic determinants of economic performance. There is only weak evidence that this effect operates through the deterioration of human capital formation caused by childhood obesity.     

生态创新系统功能、过程和可持续评估

不同国家生态创新水平有高低,生态创新系统有差异。生态创新系统是由一系列参与者通过相互作用形成的网络,目的是推动有助于生态环境和社会经济协调发展的知识和技术的生产、传播和应用。为比较不同国家生态创新系统的发展状况和可持续性,分析不同国家生态创新系统的优势和不足,提出生态创新系统两步评估法和整体分析框架。把生态创新系统的功能和过程结合起来,对生态创新系统的发展水平进行评价。重点关注系统的长期发展,即系统可持续性。基于资本的角度,包括知识、经济、人力和社会资本,建立生态创新系统可持续评估模型,考察相关资本存量、流量和风险因素。根据创新系统理论、文献回顾和国际研究比较,遴选出30个关键指标,构建涵盖2个指标矩阵的综合评价指标体系。采用主成分分析和综合评价方法,对不同国家生态创新系统的功能-过程和可持续性分别进行评价。研究表明,法国、德国、韩国、西班牙和挪威生态创新系统的功能-过程表现最强,韩国、德国、奥地利、挪威、捷克生态创新系统的可持续性表现最强。根据生态创新系统的现状和可持续性,主要生态创新国家可以分为四种类型,据此采用不同发展策略。如韩国系统现状水平和可持续性都较高,属于生态创新先进国。...     

Pulp Nonfiction: Regionalized Dynamic Model of the U.S. Pulp and Paper Industry

This article presents a modeling framework that enhances our ability to analyze the implications of policy for future sustainability of industrial systems. The framework quantifies the relationship between physical input and waste flows, capital vintage, and investment behavior in the U.S. pulp and paper industry. A regional vintage model is developed that simultaneously incorporates investment decisions, vintage structure of the capital stock, and physical material and energy flows, in addition to paper demand. Each capital vintage is specified by size, output structure, and age-specific retirement rates, as well as fiber use and energy intensities. Both embodied and disembodied technological change are incorporated, as well as greenhouse gas emissions from fuel use, and decomposition and incineration of waste. Estimated equations are used to simulate industrial futures until 2020, from a system of nonlinear differential equations.
Our results demonstrate the economic and physical inter-dependence between material and energy flows and the central role energy prices have in decision-making. For instance, an increase in average energy prices, ceteris paribus , will on average discourage paper recycling, which has implications for greenhouse gas emissions as well as for changes in energy intensity. The analysis of the data reveals diminishing rates of energy self-generation, and the immense longevity of capital, which hampers rapid change in input and carbon intensity. This stresses the importance of investment-led strategies in facilitating faster capital turnover to enhance future sustainability of the system.     

The origins of monetary income inequality: Patience,human capital,and division of labor

We present an explanation about the origins of monetary income inequality when an economically self-sufficient society opens to a market economy. The chain of associations runs from patience, to the accumulation of different forms of human capital, to self-selection into different occupations, and to the division of labor, which contributes to monetary income inequality. In a self-sufficient society, patience is exogenously determined and people rely on folk knowledge as the only form of human capital. With the establishment of schools, patient and impatient people sort themselves out by the type of human capital they begin to accumulate. Impatient people do not acquire folk knowledge because return to schooling takes many years to bear fruit. Schooling opens opportunities in occupations outside the village, whereas folk knowledge enhances employment opportunities that draw on farming or foraging. Self-selection into different occupations with different earnings potential spawns monetary income inequality. To test the explanation, we draw on data from a foraging–farming society in the Bolivian Amazon, the Tsimane'. We collected data during four consecutive quarters in 1999–2000 and a follow-up interview (2004). Data came from 151 adults (age, 16 years or more) from all households (n=48) in two villages with different levels of market exposure. During 1999–2000, impatience was associated with (a) greater folk knowledge and fewer years of schooling, (b) lower likelihood of working in wage labor, and (c) greater likelihood of working in rural subsistence occupations. People who had been patient in 1999–2000 had greater wage earnings and more modern physical assets in 2004.     

Hui family migration in Northwest China: patterns,experiences and social capital

Based on an extensive questionnaire survey in three cities in Northwest China, this article identifies the factors influencing the sole, couple and family migration of Han and Hui. We find that Han migrants are more utility-oriented and tend to circulate among different places in order to maximize their utility. Hui migrants are more likely to seek opportunities to settle in destinations with their families. They rely on Hui communities and dedicate themselves to creating networks and accumulating social capital for their families. We suggest that the accumulation of bonding capital does not necessarily suggest the increase or decrease of bridging capital. Moreover, the ethnic community should be regarded neither in negative nor positive terms but rather as a coin with two sides, pro and con. The ethnic community is a vessel, which migrants can use for minimizing risks, improving livelihoods and fostering the settlement of families.     

自然资本价值核算研究综述

目前国内外对自然资本价值核算的理论与方法尚未取得共识,无疑制约了自然资本核算在生态环境保护中积极作用的发挥。基于此,本文分别从自然资本内涵及其价值核算理论基础、国内外自然资本存量与流量核算方法实证研究、自然资本货币化价值核算的合理性等方面对已有文献进行梳理与分析,发现目前自然资本核算研究主要集中在生态产品的功能量与价值量核算而缺少生态资产货币价值量核算的研究;当前采用的生态产品价值量核算的生态系统类型系数表、本地化生态过程模型、能值当量替换三种方法在精度适用性、应用推广性和计算便捷性上各有优劣,尚待进一步的深入研究;最后对自然资本货币核算的一些争论进行了分析。通过上述研究和分析,提出如下新认识：（1）自然资本相关概念尚不统一,已经形成的认识包括：自然资本具有一定的稀缺性和使用价值,资本可分为存量资本（又称生态资产）和流量资本（又称生态系统服务）;（2）自然资本核算技术繁多,研究成果的横向比较性较差,需要通过标准化核算技术方法和建立生态环境资源数据库等措施,进一步提高核算结果的准确性和可比性;（3）相比于基于生态系统类型价值系数方法和基于非市场化货币的当量替代方法,基于本地化参数的生态系统服务过程方法更能够反映本地生态环境特征,评估分析的准确度更高,生态管理抓手更多;（4）尽管自然资本货币核算理论和实践应用仍存在一些争论,但各国政府和各类组织都在推动自然资本核算工作,自然资本的探索性核算成果已在各国生态补偿和生态损害修复等方面发挥积极作用。     

Optimal exploitation for a commercial fishing model

A two non-linear dynamic models, first one in two state variables and one control and the second one with three state variables and one control, are presented for the purpose of finding the optimal combination of exploitation, capital investment and price variation in the commercial fishing industry. This optimal combination is determined in terms of management policies. Exploitation, capital and price variation are controlled through the utilization rate of available capital. A novel feature in this model is that the variation of the capital depends on the income.     

Covid-19 in Brazil: A sad scenario

The main contribution of this article is to report general statistics about COVID-19 in Brazil, based on analysis of accumulated series of confirmed cases, deaths and lethality rates, in addition to presenting graphs of moving averages for states and municipalities. The data show that the pandemic in Brazil has grown rapidly since February 25th (date of the first reported case). Furthermore, the lethality rate of COVID-19 in Brazil is greater than in many other Latin American countries (Chile, Argentina, Uruguay and Paraguay). However, the number of new confirmed cases in Brazil has little statistical relevance because only a small part of the population has been tested. In relation to Brazilian municipalities, we highlight the 10 states with the highest lethality rates, ranked from highest to lowest. Also, predictions about the increaseor decrease innew cases and deaths for states and capital cities are presented. These results can help managers and researchers to better guide their decisions regarding COVID-19.     

Race,Community and Conflict fifty years on

This review focuses on John Rex and Robert Moore's study of migrant settlement and community relations in the Sparkbrook area of Birmingham, UK in the early 1960s. The review argues that this study, now almost fifty years old, anticipated a number of the key themes that characterize and preoccupy the current debates on migration and complex urban communities such as migrant networks and social capital, super-diversity, patterns of residence and transnationlism. The review suggests that the study has enduring value not only as a historical sociological text but in terms of the ways in which its findings resonate with contemporary urban environments and theoretical concerns.