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91.
A growing literature identifies associations between subjective and biometric indicators of wellbeing. These associations, together with the ability of subjective wellbeing metrics to predict health and behavioral outcomes, have spawned increasing interest in wellbeing as an important concept in its own right. However, some social scientists continue to question the usefulness of wellbeing metrics. We contribute to this literature in three ways. First, we introduce a biometric measure of wellbeing – pulse – that hs been little used. Using nationally representative data on 165,000 individuals from the Health Survey for England and Scottish Health Surveys we show that its correlates are similar in a number of ways to those for happiness, and that it is highly correlated with wellbeing metrics, as well as self-assessed health. Second, we examine the determinants of pulse rates in mid-life (age 42) among the 9000 members of the National Child Development Study, a birth cohort born in a single week in 1958 in Britain. Third, we track the impact of pulse measured in mid-life (age 42) on health and labor market outcomes at age 50 in 2008 and age 55 in 2013. The probability of working at age 55 is negatively impacted by pulse rate a decade earlier. The pulse rate has an impact over and above chronic pain measured at age 42. General health at 55 is lower the higher the pulse rate at age 42, while those with higher pulse rates at 42 also express lower life satisfaction and more pessimism about the future at age 50. Taken together, these results suggest social scientists can learn a great deal by adding pulse rates to the metrics they use when evaluating people’s wellbeing. 相似文献
92.
This study explores the effect on mental health and life satisfaction of working in an automatable job. We utilise an Australian panel dataset (HILDA), and take a fixed effects linear regression approach, to relate a person being in automatable work to proxies of their wellbeing. Overall, we find evidence that automatable work has a small, detrimental impact on the mental health and life satisfaction of workers within some industries, particularly those with higher levels of job automation risk, such as manufacturing. Furthermore, we find no strong trends to suggest that any particular demographic group is disproportionately impacted across industries. These findings are robust to a variety of specifications. We also find evidence of adaptation to these effects after one-year tenure on the job, indicating a limited role for firm policy. 相似文献
93.
《Revista espa?ola de geriatría y gerontología》2019,54(6):329-333
AimSatisfaction with life is a measure of protection in older adults. There lies the importance of providing quality instruments. The aim of the study was to evaluate the invariance of the life satisfaction scale (SWLS) in two samples of older adults in Spain and Peru.MethodThe participants were 857 older adults in Spain (mean age = 68.23 years, SD = 5.93) and 336 older adults in Peru (average age = 72.42, SD = 7.07). All multi-group confirmatory factor analyzes were estimated in Mplus 8.0.ResultsThe results indicate the presence of a strict invariance of the one-dimensional structure of the SWLS in samples of older adults in Spain and Peru, which allows for meaningful comparisons of latent means and covariances. Comparison of latent means showed small differences in the construct between the cultural groups.ConclusionsThe SWLS is a valid instrument for intercultural comparisons between Spanish and Peruvian population. The measurement invariance assessment contributes to a better understanding of life satisfaction in populations from different cultural contexts. 相似文献
94.
A colony of Amblyomma neumanni was started with engorged females collected from cattle in the province of Salta (24° 51S, 65° 33W), Argentina. The larvae and nymphs were fed on rabbits and the adults on calves. The non-parasitic stages were maintained in darkness at 27 ± 1°C and 83–86% RH. The life cycle (pre-feeding period not tested) had a mean duration of 205.7 days. The mean time (days) for the different phases of the cycle were as follows: feeding of females 8.8, pre-oviposition 23.8, oviposition 41.4, minimum egg incubation 76.1, feeding of larvae 8.5, pre-moult to nymphs 16.4, feeding of nymphs 7.9 and pre-moult to adults 22.8. The mean recovery rates of larvae, nymphs and females were 83.8, 85.6 and 89.3%, respectively. The nymphs moulting to females were heavier (8.1 ± 2.34 mg) than those moulting to males (6.0 ± 2.34 mg; p < 0.01), but their range of engorgement weight showed overlap (2.3–16.2 versus 2.2–12.8 mg, respectively). Two gynandromorphs were detected between the nymphs. A comparison of biological parameters of A. neumanni with other American Amblyomma species from mammals is presented. © Rapid Science Ltd. 1998 相似文献
95.
We formulate and analyze two dynamic energy budget models, a net assimilation model with constant allocation strategy and a net production model with a 2-stage allocation strategy, with the objective of determining strategies that maximize the expected lifetime reproductive energy. The per capita death rate depends on the organisms size, as for example when the main cause of death is predation. In the analysis of the net production model, the size at maturity is calculated along with the probability of reaching that size. We show that a small probability of survival to maturity is incompatible with the simple assumption of an exponential survival probability. We demonstrate that when the hazard rate is significantly greater for small individuals than large ones, it is possible for the optimum strategy to be for an individual to grow to a large size in spite of an arbitrarily small probability of survival to maturity. Numerical simulations indicate how the optimal allocation strategies depend on the parameter values. 相似文献
96.
Wulf-Peter?SchmidtEmail author Elisabeth?Dahlqvist Matthias?Finkbeiner Stephan?Krinke Silvia?Lazzari Dirk?Oschmann Sophie?Pichon Christian?Thiel 《The International Journal of Life Cycle Assessment》2004,9(6):405-416
Goal, Scope and Background The automotive industry has a long history in improving the environmental performance of vehicles - fuel economy and emission
improvements, introduction of recycled and renewable materials, etc. The European Union also aims at improving the environmental
performance of products by reducing, in particular, waste resulting from End-of-Life Vehicles (ELVs) for example. The European
Commission estimates that ELVs contribute to approximately 1 % of the total waste in Europe [9]. Other European Union strategies
are considering more life cycle aspects, as well as other impacts including resource or climate change. This article is summarizing
the results of a European Commission funded project (LIRECAR) that aims at identifying the environmental impacts and relevance
for combinations of recycling / recovery and lightweight vehicle design options over the whole life cycle of a vehicle - i.e.
manufacturing, use and recycling/recovery. Three, independent and scientific LCA experts reviewed the study according to ISO
14040. From the beginning, representatives of all Life Cycle Stakeholders have been involved (European materials & supplier
associations, an environmental Non-Governmental Organization, recycler’s association).
Model and System Definition The study compared 3 sets of theoretical vehicle weight scenarios: 1000 kg reference (material range of today’s end-of-life,
mid-sized vehicles produced in the early 1990’s) and 2 lightweight scenarios for 100 kg and 250 kg less weight based on reference
functions (in terms of comfort, safety, etc.) and a vehicle concept. The scenarios are represented by their material range
of a broad range of lightweight strategies of most European car manufacturers. In parallel, three End-of-Life (EOL) scenarios
are considered: EOL today and two theoretical extreme scenarios (100% recycling, respectively, 100% recovery of shredder residue
fractions that are disposed of today). The technical and economical feasibility of the studied scenarios is not taken into
consideration (e.g. 100% recycling is not possible).
Results and Discussion Significant differences between the various, studied weight scenarios were determined in several scenarios for the environmental
categories of global warming, ozone depletion, photochemical oxidant creation (summer smog), abiotic resource depletion, and
hazardous waste. However, these improvement potentials can be only realized under well defined conditions (e.g. material compositions,
specific fuel reduction values and EOL credits) based on case-by-case assessments for improvements over the course of the
life cycle. Looking at the studied scenarios, the relative contribution of the EOL phase represents 5% or less of the total
life cycle impact for most selected impact categories and scenarios. The EOL technology variations studied do not impact significantly
the considered environmental impacts. Exceptions include total waste, as long as stockpile goods (overburden, tailings and
ore/coal processing residues) and EOL credits are considered.
Conclusions and Recommendations LIRECAR focuses only on lightweight/recycling, questions whereas other measures (changes in safety or comfort standards, propulsion
improvements for CO2, user behavior) are beyond the scope of the study. The conclusions are also not necessarily transferable to other vehicle
concepts. However, for the question of end-of-life options, it can be concluded that LIRECAR cannot support any general recommendation
and/or mandatory actions to improve recycling if lightweight is affected. Also, looking at each vehicle, no justification
could be found for the general assumption that lightweight and recycling greatly influence the affected environmental dimension
(Global Warming Potential or resource depletion and waste, respectively). LIRECAR showed that this general assumption is not
true under all analyzed circumstances and not as significant as suggested. Further discussions and product development targets
shall not focus on generic targets that define the approach/technology concerned with how to achieve environmental improvement
(weight reduction [kg], recycling quota [%]), but on overall life cycle improvement). To enable this case-by-case assessment,
exchanges of necessary information with suppliers are especially relevant. 相似文献
97.
Demography parameters of the cereal rust mite Abacarus hystrix (Nalepa) on quack grass were studied to investigate its potential capacity of population increase in conditions of initially low density. The experiment was maintained under laboratory conditions at a constant temperature of 19.5-20.5 degrees C and 94 +/- 1% RH. Life-history data were used to calculate duration of developmental stages, survival of adults and rates of population increase. A new method of estimation of age-dependent fecundity is proposed. On average, eggs required 7.98 (n = 33, 95% CI: 7.68-8.21) days to develop into adults. Life expectancy of females was longer than that of males (9.72 and 5.41 days, respectively). The mean sex ratio, expressed as the proportion of females, was 0.80 (n = 122, CI: 0.71-0.86). The reproductive output for females was age-dependent and daily egg production reached a peak (3.83 eggs/day, CI: 2.50-5.15) on the 5th day, and then decreased steeply. The net reproductive rate (R0) was 10.12 female progeny per female per generation, the generation time (T) was 11.31 days, the intrinsic rate of increase (r) was 0.20 female progeny per female per day, and the finite rate of increase (lambda) was 1.23 female progeny per day. These estimates showed that A. hystrix has a great potential capacity for rapid population increase when colonising new hosts and its density is low. Therefore, we conclude that the population of the cereal rust mite on quack grass may rapidly build up to very high densities and can be a reservoir population, which may easily disperse and infest other, including cultivated, grasses. 相似文献
98.
Zhuang?Li Teruo?Sano Takashi?Fujita Fusaka?Nakai Yukio?HaradaEmail author 《Mycoscience》2004,45(3):200-205
A rust species on Calystegia soldanella in Japan has been treated as Puccinia convolvuli to date. However, morphological characteristics of specimens on C. soldanella collected from Japan are significantly different from those of specimens on other Calystegia and Convolvulus species from different areas of the world. It is proved by inoculation experiment that the rust on C. soldanella is specific to C. soldanella. Based on these results, Puccinia rust on C. soldanella from Japan is described as a new species, Puccinia calystegiae-soldanellae. 相似文献
99.
Charlene?B.?Hubbard David?J.?GarbaryEmail author Kwang?Young?Kim David?M.?Chiasson 《Helgoland Marine Research》2004,58(1):18-25
Kelp gametophytes were previously observed in nature living endophytically in red algal cell walls. Here we examine the interactions of two kelp species and six red algae in culture. Gametophytes of Nereocystis luetkeana (Mertens) Postels et Ruprecht became endophytic in the cell walls of Griffithsia pacifica Kylin and Antithamnion defectum Kylin, and grew epiphytically in high abundance on G. japonica Okamura and Aglaothamnion oosumiense Itono. Alaria esculenta (Linnaeus) Greville from the Atlantic coast of Nova Scotia became endophytic in Aglaothamnion oosumiense, Antithamnion defectum, Callithamnion sp., G. japonica, G. pacifica, and Pleonosporium abysicola Gardner, all from the Pacific Ocean. Some cultures were treated with phloroglucinol before infection to thicken the cell walls. The endophytic gametophytes were smaller and grew more slowly than gametophytes epiphytic on the same host. N. luetkeana failed to become endophytic in some of the potential hosts, and this may reflect host specificity, or culture artifacts. This work improves our understanding of the process of infection of red algae by kelp gametophytes, and broadens our knowledge of host specificity in endophytic symbioses.Communicated by K. Lüning 相似文献
100.