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Structural Influences (structural + influence)
Selected AbstractsLow-Temperature Restructuring Processes in PolyhydrosilanesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 13 2006Liviu Sacarescu Abstract Summary: This paper presents the structural influence of the SiH functionality on the physicochemical properties of polysilanes. New low-temperature restructuring processes were discovered using thermal analysis (TGA, DSC). Photoluminescent (FL) and X-ray photoelectron spectroscopy (XPS) measurements revealed the optoelectronic properties-chemical structure relationship of the synthesized polymers. Highly reactive SiH groups lead to restructuring of the main polysilane chain. [source] Chemical structure-based predictive model for methanogenic anaerobic biodegradation potentialENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2007William Meylan Abstract Many screening-level models exist for predicting aerobic biodegradation potential from chemical structure, but anaerobic biodegradation generally has been ignored by modelers. We used a fragment contribution approach to develop a model for predicting biodegradation potential under methanogenic anaerobic conditions. The new model has 37 fragments (substructures) and classifies a substance as either fast or slow, relative to the potential to be biodegraded in the "serum bottle" anaerobic biodegradation screening test (Organization for Economic Cooperation and Development Guideline 311). The model correctly classified 90, 77, and 91% of the chemicals in the training set (n = 169) and two independent validation sets (n = 35 and 23), respectively. Accuracy of predictions of fast and slow degradation was equal for training-set chemicals, but fast-degradation predictions were less accurate than slow-degradation predictions for the validation sets. Analysis of the signs of the fragment coefficients for this and the other (aerobic) Biowin© models suggests that in the context of simple group contribution models, the majority of positive and negative structural influences on ultimate degradation are the same for aerobic and methanogenic anaerobic biodegradation. [source] Network structural influences on the adoption of evidence-based prevention in communities,,JOURNAL OF COMMUNITY PSYCHOLOGY, Issue 7 2009Kayo Fujimoto This study examined the impact of key variables in coalition communication networks, centralization and density, on the adoption of evidence-based substance abuse prevention. Data were drawn from a network survey and a corresponding community leader survey that measured leader attitudes and practices toward substance abuse prevention programs. Two types of coalition networks were measured: advice-seeking and discussion relations. For each community, we computed network-level measurements (n=20), and then used multiple linear regression. Results showed that adoption outcomes were associated with a decrease in centralization for the advice network and an increase in centralization for the discussion network, controlling for density. This suggests that community coalitions might consider decreasing their network density in such a manner that distributes power and influence among a broader base of coalition members to seek advice about programs while simultaneously discussing these programs in a more concentrated group to facilitate decisions about which programs to adopt. © 2009 Wiley Periodicals, Inc. [source] A Unique Set of Interactions: The MSU Sustained Partnership Model of Nurse Practitioner Primary CareJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 2 2004FNP Assistant Professor, Katherine Dontje MSN Purpose To present a unified conceptual model that identifies the integral processes of nurse practitioner (NP) care delivery and that integrates major structural influences and potential outcomes. The model is further characterized to delineate the unique and "value-added" nature of NP primary care and to describe how this nature may be correlated with specific clinical outcomes. Data Sources Extensive review of the literature, relevant conceptual models, clinical experiences of the authors, and two sets of qualitative data exploring differences between NP practice and other practices. Conclusions The basis of NP primary care is the unique provider-client relationship that develops within the primary care setting. This relationship is oriented toward (a) helping clients become empowered to more appropriately manage their own care in a way that will best meet their needs, (b) encouraging mutual decision making, (c) ensuring clients' continuity of care, and (d) providing a holistic approach to primary care. The major structural influences are NP role components, interdisciplinary practice relationships, budget resources and payer mix, and environmental characteristics. The potential outcomes are increased healthpromoting behaviors, improved utilization of care, higher client satisfaction levels, and improved health status. Implications for Practice NPs can use this model to articulate the unique contribution of NP practice and its interrelationships within the broader primary care setting. Practicing NPs can use this framework to better understand the complexities of their current and future primary care practices. Faculty can utilize the concepts to help guide students' understanding of their prospective roles as advanced practice nurses. Finally, this conceptual framework can inform research about specific NP processes and related outcomes. A clearly delineated model that accurately depicts structures, processes, and outcomes relevant to NP primary care can strengthen NP education, distinguish NP practice, and advance evidenced-based research linking NP practice and outcomes. [source] Extended Car,Parrinello molecular dynamics and electronic g -tensors study of benzosemiquinone radical anion,MAGNETIC RESONANCE IN CHEMISTRY, Issue S1 2005James R. Asher Abstract Car-Parrinello molecular dynamics simulations of benzoquinone and benzosemiquinone radical anion in both aqueous solution and the gas phase have been carried out at ambient conditions. Hydrogen bonding is considerably more extensive to the anionic than to the neutral aqueous system. In addition to the conventional hydrogen bonding to the carbonyl oxygen atoms, T-stacked hydrogen bonding to the , -system is statistically and energetically significant for the semiquinone anion but not for the neutral quinone. EPR g -tensors have been calculated at DFT level for snapshots taken at regular intervals from the gas-phase and solution semiquinone anion trajectories. Different criteria for extraction of semiquinone/water clusters from the solution trajectory give insight into the effects of different interactions on the g -tensor, as does correlation of the g -tensor with statistically significant hydrogen-bond configurations identified along the trajectories. Comparison of gas-phase and solution results indicates opposite directions of direct electronic and indirect structural influences of hydrogen bonding on g -tensors. Short-time oscillations in gx along the trajectory are due mainly to CO bond vibrations. Copyright © 2005 John Wiley & Sons, Ltd. [source] A critical analysis of UK public health policies in relation to diet and nutrition in low-income householdsMATERNAL & CHILD NUTRITION, Issue 2 2006Pamela Attree phd Abstract Diet and nutrition, particularly among low-income groups, is a key public health concern in the UK. Low levels of fruit and vegetable consumption, and obesity, especially among children, have potentially severe consequences for the future health of the nation. From a public health perspective, the UK government's role is to help poorer families make informed choices within healthy frameworks for living. However, the question is , to what extent are such policies in accordance with lay experiences of managing diet and nutrition on a low-income? This paper critically examines contemporary public health policies aimed at improving diet and nutrition, identifying the underlying theories about the influences on healthy eating in poor families, and exploring the extent to which these assumptions are based on experiential accounts. It draws on two qualitative systematic reviews , one prioritizing low-income mothers' accounts of ,managing' in poverty; and the other focusing on children's perspectives. The paper finds some common ground between policies and lay experiences, but also key divergencies. Arguably, the emphasis of public health policy on individual behaviour, coupled with an ethos of empowered consumerism, underplays material limitations on ,healthy eating' for low-income mothers and children. Health policies fail to take into account the full impact of structural influences on food choices, or recognize the social and emotional factors that influence diet and nutrition. In conclusion, it is argued that while health promotion campaigns to improve low-income families' diets do have advantages, these are insufficient to outweigh the negative effects of poverty on nutrition. [source] Political History and Disparities in Safe Motherhood Between Guatemala and HondurasPOPULATION AND DEVELOPMENT REVIEW, Issue 1 2006Jeremy Shiffman Each year, worldwide, more than 500,000 women die of complications from childbirth, making this a leading cause of death globally for adult women of reproductive age. Nearly all studies that have sought to explain the persistence of high maternal mortality levels have focused on the supply of and demand for particular health services. We argue that inquiry on health services is useful but insufficient. Robust explanations for safe motherhood outcomes require examination of factors lying deeper in the causal chain. We compare the cases of Guatemala and Honduras to examine historical and structural influences on maternal mortality. Despite being a poorer country than Guatemala, Honduras has a superior safe motherhood record. We argue that four historical and structural factors stand behind this difference: Honduras's relatively stable and Guatemala's turbulent modern political history; the presence of a marginalized indigenous population in Guatemala, but not in Honduras, that the state has had difficulty reaching; a conservative Catholic Church that has played a larger role in Guatemala than Honduras in blocking priority for reproductive health; and more effective advocacy for maternal mortality reduction in Honduras than Guatemala in the face of this opposition. [source] | ||||||||||