334 resultados para Calorimetry, indirect
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The importance of wage structure is frequently interpreted as indirect evidence of the role played by labour market institutions. The current paper follows in this tradition, examining the role of wage structure in explaining the trend in the gender wage gap over the period 1973–91 for both Australia and the UK. The focus is upon whether changes in wage structure (and associated gender wage gap) both across country and over time are compatible with institutional explanations. Combining comparisons both cross-country and over time yields a more stringent, albeit indirect, test of the role of institutions.
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The males of many Bactrocera species (Diptera: Tephritidae) respond strongly and positively to a small number of plant-derived chemicals (=male lures). Males that have imbibed the lures commonly have a mating advantage over unfed males, but no female benefits have been demonstrated for females mating with lure-fed males. It has been hypothesized that the strong lure response is a case of runaway selection, where males receive direct benefits and females receive indirect benefits via 'sexy sons', or a case of sensory bias where females have a lower threshold response to lures. To test these hypotheses we studied the effects of lure feeding on male mating, remating and longevity; while for females that had mated with lure-fed males we recorded mating refractoriness, fecundity, egg viability and longevity. We used Bactrocera tryoni as our test animal and as lures the naturally occurring zingerone and chemically related, but synthetic chemical cuelure. Feeding on lures provided direct male benefits in greater mating success and increased multiple mating. For the first time, we recorded direct female effects: increased fecundity and reduced remating receptivity. Egg viability did not differ in females mated with lure-fed or unfed males. The life span of males and females exposed to lures was reduced. These results reveal direct, current-generation fitness benefits for both males and females, although the male benefits appear greater. We discuss that while lure response is indeed likely to be a sexual selection trait, there is no need to invoke runaway selection to explain its evolution.
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Mathematical descriptions of birth–death–movement processes are often calibrated to measurements from cell biology experiments to quantify tissue growth rates. Here we describe and analyze a discrete model of a birth–death-movement process applied to a typical two–dimensional cell biology experiment. We present three different descriptions of the system: (i) a standard mean–field description which neglects correlation effects and clustering; (ii) a moment dynamics description which approximately incorporates correlation and clustering effects, and; (iii) averaged data from repeated discrete simulations which directly incorporates correlation and clustering effects. Comparing these three descriptions indicates that the mean–field and moment dynamics approaches are valid only for certain parameter regimes, and that both these descriptions fail to make accurate predictions of the system for sufficiently fast birth and death rates where the effects of spatial correlations and clustering are sufficiently strong. Without any method to distinguish between the parameter regimes where these three descriptions are valid, it is possible that either the mean–field or moment dynamics model could be calibrated to experimental data under inappropriate conditions, leading to errors in parameter estimation. In this work we demonstrate that a simple measurement of agent clustering and correlation, based on coordination number data, provides an indirect measure of agent correlation and clustering effects, and can therefore be used to make a distinction between the validity of the different descriptions of the birth–death–movement process.
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Background and significance: Nurses' job dissatisfaction is associated with negative nursing and patient outcomes. One of the most powerful reasons for nurses to stay in an organisation is satisfaction with leadership. However, nurses are frequently promoted to leadership positions without appropriate preparation for the role. Although a number of leadership programs have been described, none have been tested for effectiveness, using a randomised control trial methodology. Aims: The aims of this research were to develop an evidence based leadership program and to test its effectiveness on nurse unit managers' (NUMs') and nursing staff's (NS's) job satisfaction, and on the leader behaviour scores of nurse unit managers. Methods: First, the study used a comprehensive literature review to examine the evidence on job satisfaction, leadership and front-line manager competencies. From this evidence a summary of leadership practices was developed to construct a two component leadership model. The components of this model were then combined with the evidence distilled from previous leadership development programs to develop a Leadership Development Program (LDP). This evidence integrated the program's design, its contents, teaching strategies and learning environment. Central to the LDP were the evidence-based leadership practices associated with increasing nurses' job satisfaction. A randomised controlled trial (RCT) design was employed for this research to test the effectiveness of the LDP. A RCT is one of the most powerful tools of research and the use of this method makes this study unique, as a RCT has never been used previously to evaluate any leadership program for front-line nurse managers. Thirty-nine consenting nurse unit managers from a large tertiary hospital were randomly allocated to receive either the leadership program or only the program's written information about leadership. Demographic baseline data were collected from participants in the NUM groups and the nursing staff who reported to them. Validated questionnaires measuring job satisfaction and leader behaviours were administered at baseline, at three months after the commencement of the intervention and at six months after the commencement of the intervention, to the nurse unit managers and to the NS. Independent and paired t-tests were used to analyse continuous outcome variables and Chi Square tests were used for categorical data. Results: The study found that the nurse unit managers' overall job satisfaction score was higher at 3-months (p = 0.016) and at 6-months p = 0.027) post commencement of the intervention in the intervention group compared with the control group. Similarly, at 3-months testing, mean scores in the intervention group were higher in five of the six "positive" sub-categories of the leader behaviour scale when compared to the control group. There was a significant difference in one sub-category; effectiveness, p = 0.015. No differences were observed in leadership behaviour scores between groups by 6-months post commencement of the intervention. Over time, at three month and six month testing there were significant increases in four transformational leader behaviour scores and in one positive transactional leader behaviour scores in the intervention group. Over time at 3-month testing, there were significant increases in the three leader behaviour outcome scores, however at 6-months testing; only one of these leader behaviour outcome scores remained significantly increased. Job satisfaction scores were not significantly increased between the NS groups at three months and at six months post commencement of the intervention. However, over time within the intervention group at 6-month testing there was a significant increase in job satisfaction scores of NS. There were no significant increases in NUM leader behaviour scores in the intervention group, as rated by the nursing staff who reported to them. Over time, at 3-month testing, NS rated nurse unit managers' leader behaviour scores significantly lower in two leader behaviours and two leader behaviour outcome scores. At 6-month testing, over time, one leader behaviour score was rated significantly lower and the nontransactional leader behaviour was rated significantly higher. Discussion: The study represents the first attempt to test the effectiveness of a leadership development program (LDP) for nurse unit managers using a RCT. The program's design, contents, teaching strategies and learning environment were based on a summary of the literature. The overall improvement in role satisfaction was sustained for at least 6-months post intervention. The study's results may reflect the program's evidence-based approach to developing the LDP, which increased the nurse unit managers' confidence in their role and thereby their job satisfaction. Two other factors possibly contributed to nurse unit managers' increased job satisfaction scores. These are: the program's teaching strategies, which included the involvement of the executive nursing team of the hospital, and the fact that the LDP provided recognition of the importance of the NUM role within the hospital. Consequently, participating in the program may have led to nurse unit managers feeling valued and rewarded for their service; hence more satisfied. Leadership behaviours remaining unchanged between groups at the 6 months data collection time may relate to the LDP needing to be conducted for a longer time period. This is suggested because within the intervention group, over time, at 3 and 6 months there were significant increases in self-reported leader behaviours. The lack of significant changes in leader behaviour scores between groups may equally signify that leader behaviours require different interventions to achieve change. Nursing staff results suggest that the LDP's design needs to consider involving NS in the program's aims and progress from the outset. It is also possible that by including regular feedback from NS to the nurse unit managers during the LDP that NS's job satisfaction and their perception of nurse unit managers' leader behaviours may alter. Conclusion/Implications: This study highlights the value of providing an evidence-based leadership program to nurse unit managers to increase their job satisfaction. The evidence based leadership program increased job satisfaction but its effect on leadership behaviour was only seen over time. Further research is required to test interventions which attempt to change leader behaviours. Also further research on NS' job satisfaction is required to test the indirect effects of LDP on NS whose nurse unit managers participate in LDPs.
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This paper evaluates the efficiency of a number of popular corpus-based distributional models in performing discovery on very large document sets, including online collections. Literature-based discovery is the process of identifying previously unknown connections from text, often published literature, that could lead to the development of new techniques or technologies. Literature-based discovery has attracted growing research interest ever since Swanson's serendipitous discovery of the therapeutic effects of fish oil on Raynaud's disease in 1986. The successful application of distributional models in automating the identification of indirect associations underpinning literature-based discovery has been heavily demonstrated in the medical domain. However, we wish to investigate the computational complexity of distributional models for literature-based discovery on much larger document collections, as they may provide computationally tractable solutions to tasks including, predicting future disruptive innovations. In this paper we perform a computational complexity analysis on four successful corpus-based distributional models to evaluate their fit for such tasks. Our results indicate that corpus-based distributional models that store their representations in fixed dimensions provide superior efficiency on literature-based discovery tasks.
Promoting a more positive traffic safety culture in Australia : lessons learnt and future directions
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Adopting a traffic safety culture approach, this paper identifies and discusses the ongoing challenge of promoting the road safety message in Australia. It is widely acknowledged that mass media and public education initiatives have played a critical role in the significant positive changes witnessed in community attitudes to road safety in the last three to four decades. It could be argued that mass media and education have had a direct influence on behaviours and attitudes, as well as an indirect influence through signposting and awareness raising functions in conjunction with enforcement. Great achievements have been made in reducing fatalities on Australia’s roads; a concept which is well understood among the international road safety fraternity. How well these achievements are appreciated by the general Australian community however, is not clear. This paper explores the lessons that can be learnt from successes in attitudinal and behaviour change in regard to seatbelt use and drink driving in Australia. It also identifies and discusses key challenges associated with achieving further positive changes in community attitudes and behaviours, particularly in relation to behaviours that may not be perceived by the community as dangerous, such as speeding and mobile phone use while driving. Potential strategies for future mass media and public education campaigns to target these challenges are suggested, including ways of harnessing the power of contemporary traffic law enforcement techniques, such as point-to-point speed enforcement and in-vehicle technologies, to help spread the road safety message.
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Background This is an updated version of a Cochrane review first published in Issue 1, 2010 of The Cochrane Library. In many clinical areas, integrated care pathways are utilised as structured multidisciplinary care plans that detail essential steps in caring for patients with specific clinical problems. In particular, care pathways for the dying have been developed as a model to improve care of patients who are in the last days of life. The care pathways were designed with an aim of ensuring that the most appropriate management occurs at the most appropriate time and that it is provided by the most appropriate health professional. There have been sustained concerns about the safety of implementing end-of-life care pathways, particularly in the UK. Therefore, there is a significant need for clinicians and policy makers to be informed about the effects of end-of-life care pathways with a systematic review. Objectives To assess the effects of end-of-life care pathways, compared with usual care (no pathway) or with care guided by another end-of-life care pathway across all healthcare settings (e.g. hospitals, residential aged care facilities, community). In particular, we aimed to assess the effects on symptom severity and quality of life of people who are dying; those related to the care such as families, carers and health professionals; or a combination of these. Search Methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 6, 2013), MEDLINE, EMBASE, PsycINFO, CINAHL, review articles and reference lists of relevant articles.We conducted the original search in September 2009, and the updated search in June 2013. Selection Criteria All randomised controlled trials (RCTs), quasi-randomised trial or high-quality controlled before-and-after studies comparing use versus non-use of an end-of-life care pathway in caring for the dying. Data Collection and Analysis Two review authors assessed the results of the searches against the predetermined criteria for inclusion. Main Results The original review identified 920 titles. The updated search found 2042 potentially relevant titles (including the original 920), but no additional studies met criteria for inclusion in the review update. Authors’ Conclusions With sustained concerns about the safety of the pathway implementation and the lack of available evidence on important patient and relative outcomes, recommendations for the use of end-of-life pathways in caring for the dying cannot be made. Since the last version of this review, no new studies met criteria for inclusion in the review update. With recently documented concerns related to the potential adverse effects associated with Liverpool Care Pathway (the most commonly used end-of-life care pathway), we do not recommend decision making based on indirect or low-quality evidence. All health services using end-of-life care pathways are encouraged to have their use of the pathway, to date, independently audited. Any subsequent use should be based on carefully documented evaluations. Large RCTs or other well-designed controlled studies are urgently required for the evaluation of the use of end-of-life care pathways in caring for dying people in various clinical settings. In future studies, outcome measures should include benefits or harms concerning the outcomes of interest in this review in relation to patients, families, carers and health professionals.
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Objective: To evaluate the economic burden of malignant neoplasms in Shandong province in order to provide scientific evidence for policy-making. Methods: The main sources for this study were the data from the third sampling survey of death cause in 2006 and cancer prevalence survey in 2007 in Shandong province. The direct medical cost was calculated based on the survey data. The indirect cost due to mortality and morbidity were estimated with human capital approach based on the data of disability-adjusted life years derived from the two surveys and gross domestic product (GDP) data. The total economic burden was the sum of direct medical cost and indirect cost. The uncertainty analysis was conducted according to the methodology in global burden of disease study. Results: The total cost of cancer in Shandong province in 2006 estimated was 18 057 million Yuan RMB (95% confidence interval:16 817 - 19 393 million), which accounted for 0. 83% of the total GDP. The direct medical cost,indirect mortality cost and indirect morbidity cost accounted for 17.28%, 78.53%, and 4.20% of total economic burden of malignant neoplasms, respectively. Liver,lung and stomach cancer were the top three tumors with heavier economic burden, with accounted for more than one half (57. 83%) of the total economic burden of all cancers. The uncertainty of total burden estimated was around ± 7%, which mainly derived from the uncertainty of indirect economic burden. Conclusion: The influence of cancers on social economy is dominated by the loss of productivity, especially by the productivity loss due to premature death. Liver, lung and stomach cancer are the major cancers for disease control and prevention in Shandong province. Abstract in Chinese 目的 评价山东省恶性肿瘤经济负担,为卫生决策提供科学依据. 方法 以2006年山东省第3次死因回顾抽样凋查资料和2007年山东省恶性肿瘤现患状况抽样调查资料为基础,测算全省直接医疗成本;采用人力资本法测算死亡间接负担和伤残间接负担;参考全球疾病负担研究的方法对测算结果的不确定性进行分析. 结果 2006年山东省因恶性肿瘤导致的总经济负担为180.57亿元(95%CI=16 817~19 393),占全省GDP总量的0.83%,其中直接医疗成本占总负担的17.28%,死亡造成的间接经济负担占78.53%,伤残所致间接经济负担占4.20%;肝癌、肺癌和胃癌为山东省经济负担最重的3种恶性肿瘤,总经济负担合计占全部恶性肿瘤的57.83%;总经济负担估计结果的不确定性范围在±7%左右,主要取决于间接经济负担的不确定性. 结论 恶性肿瘤对社会经济的影响主要通过生产力的损失产生作用,并以死亡所致生产力损失为主;肝癌、肺癌和胃癌应是山东省恶性肿瘤预防控制的重点.
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Research Question/Issue: Family control in family firms can extend beyond the direct involvement of family members, but identifying these mechanisms is difficult in most markets. We utilize unique disclosures made by Taiwanese firms to examine the role played by family representatives in listed family firms. Family representatives are non-family members that represent the controlling family’s indirect shareholdings in the firm. We examine whether family representatives are used in the same manner as family members and whether they provide net benefits or costs to shareholders. Research Findings/Insights: In our sample of listed family firms, we find that omitting family representatives understates the influence of controlling families by 46 percent. We show that family representatives are associated with net costs to shareholders, but to a lesser extent than family members. We also find that controlling families use family members and family representatives differently. Family members are more involved in older family firms and in firms founded by the family. Family representatives are more involved in acquired and second generation family firms and in larger firms with more fixed assets. Theoretical/Academic Implications: We apply agency theory to the use of family representatives and show that family representatives are being used by controlling families to extend their influence within their firms, increasing agency costs to minority shareholders. Practitioner/Policy Implications: For policymakers, our analysis shows that disclosure of family member and representative relationships within firms is important and value-relevant to investors. Furthermore, our results suggest that firm performance could be improved by limiting the involvement of family members and family representatives in family firms.
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Hong Kong is a densely populated city suffering badly from the urban heat island effect. Green wall offers a means of ameliorating the situation but there are doubts over its suitability in Hong Kong’s unique environment. In this paper, we look at the potential for green walls in Hong Kong first by summarising some of the Chinese green walling systems and associated vegetation in use, then by an introduction to three existing green walls in Hong Kong, and finally through a small experiment aimed at identifying the likely main effects of green walled housing. The results indicate that green walling in Hong Kong is likely to provide enhanced internal house environment in terms of warm weather temperature reduction, stabilisation and damping, with direct energy savings in air-conditioning and indirect district benefits of reduced heat island effect and carbon emissions. The green walling insulation properties also suggest the possibility of warmer homes in winter and/or energy savings in mechanical heating provision.
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Hong Kong is a densely populated city suffering badly from the urban heat island effect. Green wall offers a means of ameliorating the situation but there are doubts over its suitability in Hong Kong’s unique environment. In this paper, we look at the potential for green walls in Hong Kong first by summarizing some of the Chinese green walling systems and associated vegetation in use, then by an introduction to three existing green walls in Hong Kong, and finally through a small experiment aimed at identifying the likely main effects of green walled housing. The results indicate that green walling in Hong Kong is likely to provide enhanced internal house environment in terms of warm weather temperature reduction, stabilization and damping, with direct energy savings in air-conditioning and indirect district benefits of reduced heat island effect and carbon emissions. The green walling insulation properties also suggest the possibility of warmer homes in winter and/or energy savings in mechanical heating provision.
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Aims To integrate existing theoretical perspectives on change management, subjective fit and occupational stress to better understand the effects of change on employee adjustment. Background Although subjective fit with organizational goals and objectives has been shown to have positive effects on employee adjustment, its role in the organizational change–occupational stress context is not understood. This represents a caveat in research when considering the notion that those who feel that they fit with the organization's goals may be better equipped to reconcile and deal with change. Design A cross-sectional survey of nurses from public and non-profit sector hospitals was conducted. Method Data were collected from 252 public and non-profit sector nurses via online surveys. Data were collected from June–October in 2010. Structural equation modelling was used to test the direct and indirect effects among the focal variables. Results The results showed that public and non-profit nurses experience flexibility-limiting and flexibility-promoting change initiatives and that these are differentially related to the perception of administrative stressors and adjustment with these relationships directly and indirectly influenced by perceptions of subjective fit. Flexibility-limiting change initiatives led to lower levels of subjective fit, higher levels of administrative stressors and less favourable adjustment. On the other hand, flexibility-promoting change practices led to higher levels of subjective fit, lower levels of administrative stressors and ultimately better adjustment. Conclusion The results further the theoretical understanding of the role of subjective fit in organizational change and occupational stress theories.
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Background: Microvessel density, an indirect measure of angiogenesis, has been shown to be an independent prognostic marker in many solid tumours including non-small cell lung cancer (NSCLC). Platelets transport and release angiogenic growth factors. Platelets are increasingly likely to adhere to tumour microvessels due to raised expression of platelet-binding proteins and stasis in blood-flow. Increased vascular permeability in tumour microvessels facilitates platelet extravasation into the extracellular matrix. Adherence and extravasation both lead to platelet activation and release of growth factors capable of instigating the angiogenic process. Methods: A total of 181 patients were identified who underwent resection of stage I-IIIa NSCLC with a post-operative survival >60 days. Patients were followed-up for a minimum of 24 months. Sections from the tumour periphery were stained for the endothelial marker CD34 (Novocastra NCL-END) using standard ABC immunohistochemistry. Chalkley counting was used to assess microvessel density. Results: A pre-operative platelet count greater than the median and above the normal range (>400) was associated with a poor outcome (P = 0.01 and P = 0.04, respectively). Tumours with an above median and high Chalkley count (upper tertile) had a worse prognosis (P = 0.007 and P = 0.0006, respectively). There was no association between platelet count and Chalkley count. Conclusions: Platelet and microvessel counts are both potential prognostic markers for NSCLC. The role of platelets in the angiogenic process needs to be further investigated. (C) 2000 Elsevier Science Ireland Ltd.
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Growth and metastatic spread of invasive carcinoma depends on angiogenesis, the formation of new blood vessels. Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic growth factor for a number of solid tumors, including lung, bladder, colorectal, and renal cell cancer. Cervical intraepithelial neoplasia (CIN) is the precursor to squamous cell cervical carcinoma (SCC). Mean vessel density (MVD) increases from normal cervical tissue, through low- and high-grade CIN to SCC. We evaluated PD-ECGF immunoreactivity and correlated its expression with MVD in normal, premalignant, and malignant cervical tissue. PD-ECGF expression was assessed visually within the epithelial tissues and scored on the extent and intensity of staining. MVD was calculated by counting the number of vessels positive for von Willebrand factor per unit area subtending normal or CIN epithelium or within tumor hotspots for SCC. Cytoplasmic and/or nuclear PD-ECGF immunoreactivity was seen in normal epithelium. PD-ECGF expression significantly increased with histologic grade from normal, through low- and high-grade CIN, to SCC (P < .02). A progressive significant increase in the microvessel density was also seen, ranging from a mean of 28 vessels for normal tissue to 57 for SCC (P < .0005). No correlation was found between PD-ECGF expression and MVD (P = .45). We conclude that PD-ECGF expression and MVD increase as the cervix transforms from a normal to a malignant phenotype. PD-ECGF is thymidine phosphorylase, a key enzyme in the activation of fluoropyrimidines, including 5-fluorouracil. Evaluation of PD-ECGF thymidine phosphorylase expression may be important in designing future chemotherapeutic trials in cervical cancer. Copyright (C) 2000 by W.B. Saunders Company.
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Major imperfections in crosslinked polymers include loose or dangling chain ends that lower the crosslink d., thereby reducing elastic recovery and increasing the solvent swelling. These imperfections are hard to detect, quantify and control when the network is initiated by free radical reactions. As an alternative approach, the sol-gel synthesis of a model poly(ethylene glycol) (PEG-2000) network is described using controlled amts. of bis- and mono-triethoxy silyl Pr urethane PEG precursors to give silsesquioxane (SSQ, R-SiO1.5) structures as crosslink junctions with a controlled no. of dangling chains. The effect of the no. of dangling chains on the structure and connectivity of the dried SSQ networks has been detd. by step-crystn. differential scanning calorimetry. The role that micelle formation plays in controlling the sol-gel PEG network connectivity has been studied by dynamic light scattering of the bis- and mono-triethoxy silyl precursors and the networks have been characterized by 29Si solid state NMR, sol fraction and swelling measurements. These show that the dangling chains will increase the mesh size and water uptake. Compared to other end-linked PEG hydrogels, the SSQ-crosslinked networks show a low sol fraction and high connectivity, which reduces solvent swelling, degree of crystallinity and the crystal transition temp. The increased degree of freedom in segment movement on the addn. of dangling chains in the SSQ-crosslinked network facilitates the packing process in crystn. of the dry network and, in the hydrogel, helps to accommodate more water mols. before reaching equil.