93 research outputs found
Slower Visuomotor Corrections with Unchanged Latency are Consistent with Optimal Adaptation to Increased Endogenous Noise in the Elderly
We analyzed age-related changes in motor response in a visuomotor compensatory tracking task. Subjects used a manipulandum to attempt to keep a displayed cursor at the center of a screen despite random perturbations to its location. Cross-correlation analysis of the perturbation and the subject response showed no age-related increase in latency until the onset of response to the perturbation, but substantial slowing of the response itself. Results are consistent with age-related deterioration in the ratio of signal to noise in visuomotor response. The task is such that it is tractable to use Bayesian and quadratic optimality assumptions to construct a model for behavior. This model assumes that behavior resembles an optimal controller subject to noise, and parametrizes response in terms of latency, willingness to expend effort, noise intensity, and noise bandwidth. The model is consistent with the data for all young (n = 12, age 20–30) and most elderly (n = 12, age 65–92) subjects. The model reproduces the latency result from the cross-correlation method. When presented with increased noise, the computational model reproduces the experimentally observed age-related slowing and the observed lack of increased latency. The model provides a precise way to quantitatively formulate the long-standing hypothesis that age-related slowing is an adaptation to increased noise
Caloric restriction counteracts age-dependent changes in prolyl-4-hydroxylase domain (PHD) 3 expression
Caloric restriction remains the most reproducible measure known to extend life span or diminish age-associated changes. Previously, we have described an elevated expression of the prolyl-4-hydroxylase domain (PHD) 3 with increasing age in mouse and human heart. PHDs modulate the cellular response towards hypoxia by regulating the stability of the α-subunit of the transcriptional activator hypoxia inducible factor (HIF). In the present study we demonstrate that elevated PHD3, but not PHD1 or PHD2, expression is not restricted to the heart but does also occur in rat skeletal muscle and liver. Elevated expression of PHD3 is counteracted by a decrease in caloric intake (40% caloric restriction applied for 6 months) in all three tissues. Age-associated changes in PHD3 expression inversely correlated with the expression of the HIF-target gene macrophage migration inhibitory factor (MIF), which has been previously described to be involved in cellular HIF-mediated anti-ageing effects. These data give insight into the molecular consequences of caloric restriction, which influences hypoxia-mediated gene expression via PHD3
CSR, co-optation and resistance: the emergence of new agnostic relations between business and civil society
This article examines the theoretical implications of the changing relationships between NGOs and businesses that have emerged as a response to the evolving agenda around CSR and sustainable development. In particular, it focuses upon examining whether greater engagement from non-governmental organisations (NGOs) in this area reflects a process of appropriation and co-optation of protest by the business community. To examine this process, the article considers two forms of appropriation—appropriation of language and appropriation via participation—as a basis for discussion. While co-optation pressures are identified within both areas, the article argues that co-optation is identified almost as an inevitable outcome of engagement without significant consideration of the ability of movements to identify and respond to these processes. In identifying an alternative approach, the article utilises Mouffe’s framework of agonistic pluralism. Mouffe’s framework, it is argued, provides an understanding of the way in which agonistic relationships are emerging between NGOs and businesses while highlighting the continuance of conflict between parties struggling to influence the contested interpretations of responsible business
Applications of microarray technology in breast cancer research
Microarrays provide a versatile platform for utilizing information from the Human Genome Project to benefit human health. This article reviews the ways in which microarray technology may be used in breast cancer research. Its diverse applications include monitoring chromosome gains and losses, tumour classification, drug discovery and development, DNA resequencing, mutation detection and investigating the mechanism of tumour development
Working passionately does not always pay off : the negative moderating role of passion on the relationship between deliberate practice and venture performance
Deliberate practice, an iterative process that leads to expertise, is found to be positively associated with superior performance in domains such as sports, education, and entrepreneurship. At the same time, deliberate practice is also seen as being less than enjoyable and difficult to pursue consistently. As such, passion is considered to be a vital motivator of engagement in and maintenance of deliberate practice. Despite the evident importance of passion, the relationship between passion and deliberate practice in entrepreneurship has not been subject to sufficient empirical evaluation. Therefore, in this study, we consider the way in which passion moderates the relationship between deliberate practice and venture performance. We hypothesize that deliberate practice is positively related to venture performance and that passion positively moderates this relationship. We find support for our first hypothesis, in line with previous studies. However, contrary to our second hypothesis, we find that entrepreneurial passion negatively moderates the deliberate practice-venture performance relationship. In response to this finding, we provide possible explanations as to why this negative moderation effect was observed by drawing on Kolb’s experiential learning cycle
Corporate social responsibility in Europe, North American and Asia: 2004 Survey Results
This paper builds on previous work of the author in assessing policies on corporate social responsibility (CSR) based on 20 elements. The elements are based on international conventions, codes of conduct and industry best practice. In a second survey of current priorities for CSR among large listed companies, the paper examines the written policies of companies in 15 countries in Europe, North America and Asia. The second survey demonstrates an increased emphasis on ethics, bribery and corruption and increased policies among companies on child labour compared with the first survey. It shows that one cannot assume that Asian countries are less developed than their Western counterparts and points to a growing trend of CSR in Japan, in particular. Nevertheless, it is demonstrated that there is a link between the development of CSR and the economic development of countries and that many CSR policies are based on localised issues and cultural traditions at a country level. Supply chain aspects of CSR are growing in importance, particularly among countries with a strong trading tradition
Corporate Social Responsibility in Europe and Asia: Critical Elements and Best Practice
This paper maps out 20 elements of corporate social responsibility (CSR) that businesses can adopt. The elements are based on international conventions, codes of conduct and industry best practice. The usefulness of the elements is tested in a survey of the written policies of companies in 12 countries in Europe and Asia. Results point to an emphasis on internal aspects of CSR and supply chain management. However, wider ethical, accountability and citizenship aspects of CSR are less well developed, and the paper points to a need for more action from the business community in this respect. With respect to many elements, Asian companies seem to be doing less than are European companies. However, there are some notable exceptions to this when it comes to elements associated with trade. Moreover, some significant differences in priorities can, in part, reflect issues that are identified as more important in specific countries. Although European companies are usually ahead of Asian companies with respect to their CSR agendas, there is great scope for companies to learn from each other
Commentary: Regional Environmental Management Systems: Lessons and Challenges for Industrial Ecology Research
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