125 resultados para Climatic Groups


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A commercially available coconut-shell-derived active carbon was oxidized with nitric acid, and both the original and oxidized active carbons were treated with ammonia at 1073 K to incorporate nitrogen functional groups into the carbon. An active carbon with very high nitrogen content (similar to9.4 wt % daf) was also prepared from a nitrogen-rich precursor, polyacrylonitrile (PAN). These nitrogen-rich carbons had points of zero charge (pH(pzc)) similar to H-type active carbons. X-ray absorption near-edge structure (XANES) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and temperature-programmed desorption (TPD) were used to characterize the nitrogen functional groups in the carbons. The nitrogen functional groups present on the carbon surface were pyridinic, pyrrolic (or indolic), and pyridonic structures. The adsorption of transition metal cations Cd2+, Ni2+, and Cu2+ from aqueous solution on the suite of active carbons showed that adsorption was markedly higher for carbons with nitrogen functional groups present on the surface than for carbons with similar pH(pzc) values. In contrast, the adsorption characteristics of Ca2+ from aqueous solution were similar for all the carbons studied. Flow microcalorimetry (FMC) studies showed that the enthalpies of adsorption of Cd2+(aq) on the active carbons with high nitrogen contents were much higher than for nitric acid oxidized carbons studied previously, which also had enhanced adsorption characteristics for metal ion species. The enthalpies of adsorption of Cu2+ were similar to those obtained for Cd2+ for specific active carbons. The nitrogen functional groups in the carbons act as surface coordination sites for the adsorption of transition metal ions from aqueous solution. The adsorption characteristics of these carbons are compared with those of oxidized carbons.

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This article reports upon results from a European Union funded project on the integration of children of international migrants in Britain, France and Germany. It provides both a descriptive and a multivariate analysis of the factors that determine attitudes towards ideal family size. The results reveal that there are large differences between ethnic groups in Britain: Indian and Pakistani respondents in Britain expressed a preference for significantly larger families. However, many children of international migrants expressed a desire for smaller families than the autochthonous population in both countries. This was particularly the case for Portuguese respondents in France and Turks in Germany. Religious affiliation also had a significant effect, above and beyond ethnicity per se. Both Moslems and Christians preferred larger families than those with no religious affiliation. The article concludes that ethnic differences in attitudes towards fertility behaviour will remain important in the foreseeable future in western Europe, particularly in Britain.

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We give a necessary and sufficient condition for two ax+b-like groups to have isomorphic C*-algebras. In particular, we show that there are many non-isomorphic ax+b -like Lie groups having isomorphic group C*-algebras.

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We describe the C*-algebras of " ax+b" -like groups in terms of algebras of operator fields defined over their dual spaces.

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Time-resolved DRIFTS, MS, and resistance measurements were used to study the interaction of undoped and Pd-doped SnO2 with H-2 in air and argon at 300 degrees C. Using first-order kinetics, we compare the time constants for the resistance drop and its partial recovery with those of the surface hydroxyl evolution and water formation in the gas phase upon exposure to hydrogen. In the case of the undoped oxide, resistance and bridging hydroxyls (BOHs) evolve similarly, manifesting a fast main drop followed by recovery at a similar rate. The rate of water formation for this material was found to be much slower than that of the main drop in both the resistance and BOHs. In contrast, the resistance change for SnO2-Pd appeared to be similar to that of water formation, and no correlation was found between the evolution of resistance and surface OHs. Isotopic exchange on both materials revealed that water formation occurs via fast and slow hydrogen transfer to surface oxygen species. While the former originates from just-adsorbed hydrogen, the latter appears to proceed from the preadsorbed OHs. Both surfaces exhibit close interaction between chemisorbed oxygen and existing bridging OH groups, indicating that the latter is an intermediate in the hydrogen oxidation and generation of donor states on the surface.

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Introduction: Poor nutritional status among older people is well documented with 40% of older people reported as malnourished on hospital admission. Poor nutrition contributes to increased infection, poorer patient outcomes and death and longer hospital stays. In this study, we assessed the ‘nutrition narrative’ from older hospital patients together with nutrition knowledge among nursing and medical staff and students.
Methods: The study used a convenience sample of older people (30, mean age 82 years) in two large geographically separate city hospitals. Patients mentally alert and consenting, gave a recorded ‘nutrition narrative’ to get a sense of how they felt their nutritional needs were being met in hospital. Main themes were identified by grounded analysis framework. Focus groups were recruited from medical/nursing teachers and students to assess their working knowledge of nutrition and the nutritional needs of the older patient group.
Results: Analysis of the ‘nutrition narrative’ suggested several themes (i) staff should listen to patients' needs/wishes in discussion with themselves and family members (ii) staff should continue to encourage and progress a positive eating experience (iii) staff should monitor food eaten/or not eaten and increase regular monitoring of weight. The focus groups with medical and nursing students suggested a limited knowledge about nutritional care of older people and little understanding about roles or cross-talk about nutrition across the multidisciplinary groups.
Conclusions: The ‘nutrition narrative’ themes suggested that the nutritional experience of older people in hospital can and must be improved. Nursing and medical staff providing medical and nursing care need better basic knowledge of nutrition and nutritional assessment, an improved understanding of the roles of the various multidisciplinary staff and of hospital catering pathways. Care professionals need to prioritise patient nutrition much more highly and recognise nutritional care as integral to patient healing and recovery

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Our review of paleoclimate information for New Zealand pertaining to the past 30,000 years has identified a general sequence of climatic events, spanning the onset of cold conditions marking the final phase of the Last Glaciation, through to the emergence to full interglacial conditions in the early Holocene. In order to facilitate more detailed assessments of climate variability and any leads or lags in the timing of climate changes across the region, a composite stratotype is proposed for New Zealand. The stratotype is based on terrestrial stratigraphic records and is intended to provide a standard reference for the intercomparison and evaluation of climate proxy records. We nominate a specific stratigraphic type record for each climatic event, using either natural exposure or drill core stratigraphic sections. Type records were selected on thebasis of having very good numerical age control and a clear proxy record. In all cases the main proxy of the type record is subfossil pollen. The type record for the period from ca 30 to ca 18 calendar kiloyears BP (cal. ka BP) is designated in lake-bed sediments from a small morainic kettle lake (Galway tarn) in western South Island. The Galway tarn type record spans a period of full glacial conditions (Last Glacial Coldest Period, LGCP) within the Otira Glaciation, and includes three cold stadials separated by two cool interstadials. The type record for the emergence from glacial conditions following the termination of the Last Glaciation (post-Termination amelioration) is in a core of lake sediments from a maar (Pukaki volcanic crater) in Auckland, northern North Island, and spans from ca 18 to 15.64±0.41 cal. ka BP. The type record for the Lateglacial period is an exposure of interbedded peat and mud at montane Kaipo bog, eastern North Island. In this high-resolution type record, an initial mild period was succeeded at 13.74±0.13 cal. ka BP by a cooler period, which after 12.55±0.14 cal. ka BP gave way to a progressive ascent to full interglacial conditions that were achieved by 11.88±0.18 cal. ka BP. Although a type section is not formally designated for the Holocene Interglacial (11.88±0.18 cal. ka BP to the present day), the sedimentary record of Lake Maratoto on the Waikato lowlands, northwestern North Island, is identified as a prospective type section pending the integration and updating of existing stratigraphic and proxy datasets, and age models. The type records are interconnected by one or more dated tephra layers, the ages of which are derived from Bayesian depositional modelling and OxCal-based calibrations using the IntCal09 dataset. Along with the type sections and the Lake Maratoto record, important, well-dated terrestrial reference records are provided for each climate event. Climate proxies from these reference records include pollen flora, stable isotopes from speleothems, beetle and chironomid fauna, and glacier moraines. The regional composite stratotype provides a benchmark against which to compare other records and proxies. Based on the composite stratotype, we provide an updated climate event stratigraphic classification for the New Zealand region. © 2013 Elsevier Ltd.

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The inclusion of community activists in policy planning is increasingly recognized at the highest international level. This article shows how the use of Participatory Action Research (PAR) can present a deeper and more holistic picture of the experiences of Civil Society Organizations (CSOs) in shaping national-level social policy. By utilizing action-based research, the Community and Voluntary Pillar (CVP) of Ireland’s system of social partnership is shown to be an important agent in deliberating national bargaining outcomes (known as the Towards 2016 national agreement). The key contribution of this research is the reflective methodological considerations in terms of PAR design, execution and participant integration in the research process as a way to enrich and develop a deeper and more informed community of practice.

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The thriving and well-established field of Law and Society (also referred to as Socio-legal Studies) has diverse methodological influences; it draws on social-scientific and arts-based methods. The approach of scholars researching and teaching in the field often crosses disciplinary borders, but, broadly speaking, Law and Society scholarship goes behind formalism to investigate how and why law operates, or does not operate as intended, in society. By exploring law’s connections with broader social and political forces—both domestic and international—scholars gain valuable perspectives on ideology, culture, identity, and social life. Law and Society scholarship considers both the law in contexts, as well as contexts in law.
Law and Society flourishes today, perhaps as never before. Academic thinkers toil both on the mundane and the local, as well as the global, making major advances in the ways in which we think both about law and society. Especially over the last four decades, scholarly output has rapidly burgeoned, and this new title from Routledge’s acclaimed Critical Concepts in Law series answers the need for an authoritative reference collection to help users make sense of the daunting quantity of serious research and thinking.
Edited by the leading scholars in the field, Law and Society brings together in four volumes the vital classic and contemporary contributions. Volume I is dedicated to historical antecedents and precursors. The second volume covers methodologies and crucial themes. The third volume assembles key works on legal processes and professional groups, while the final volume of the collection focuses on substantive areas. Together, the volumes provide a one-stop ‘mini library’ enabling all interested researchers, teachers, and students to explore the origins of this thriving sub discipline, and to gain a thorough understanding of where it is today.

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1. Quantitative reconstruction of past vegetation distribution and abundance from sedimentary pollen records provides an important baseline for understanding long term ecosystem dynamics and for the calibration of earth system process models such as regional-scale climate models, widely used to predict future environmental change. Most current approaches assume that the amount of pollen produced by each vegetation type, usually expressed as a relative pollen productivity term, is constant in space and time.
2. Estimates of relative pollen productivity can be extracted from extended R-value analysis (Parsons and Prentice, 1981) using comparisons between pollen assemblages deposited into sedimentary contexts, such as moss polsters, and measurements of the present day vegetation cover around the sampled location. Vegetation survey method has been shown to have a profound effect on estimates of model parameters (Bunting and Hjelle, 2010), therefore a standard method is an essential pre-requisite for testing some of the key assumptions of pollen-based reconstruction of past vegetation; such as the assumption that relative pollen productivity is effectively constant in space and time within a region or biome.
3. This paper systematically reviews the assumptions and methodology underlying current models of pollen dispersal and deposition, and thereby identifies the key characteristics of an effective vegetation survey method for estimating relative pollen productivity in a range of landscape contexts.
4. It then presents the methodology used in a current research project, developed during a practitioner workshop. The method selected is pragmatic, designed to be replicable by different research groups, usable in a wide range of habitats, and requiring minimum effort to collect adequate data for model calibration rather than representing some ideal or required approach. Using this common methodology will allow project members to collect multiple measurements of relative pollen productivity for major plant taxa from several northern European locations in order to test the assumption of uniformity of these values within the climatic range of the main taxa recorded in pollen records from the region.

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This paper contributes to the literature on centrality measures in economics by defining a team game and identifying the key players and key groups
in the game. We extend the work of Ballester et al. (Econometrica, 2006) by incorporating a network outcome component in the players' payoff functions and prove that there is a unique interior Nash Equilibrium in pure strategies. We develop a team intercentrality measure based on alternative scenarios that capture the externality created by teammates on each player.

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This paper investigates a series of dendrons based on the Newkome dendritic scaffold that displays a naturally occurring polyamine (spermine) on their surface. These dendrons have previously been shown to interact with DNA in a generation dependent manner with the more highly branched dendrons exhibiting a strong multivalency effect for the spermine surface groups. In this paper, we investigate the ability of these dendrons to transfect DNA into cells (human breast carcinoma cells, MDA-MB-231, and murine myoblast cells, C2C12) as determined by the luciferase assay. Although the dendrons are unable to transfect DNA in their own right, they are capable of delivering DNA in vitro when administered with chloroquine, which assists with escape from endocytic vesicles. The cytotoxicity of the dendrons was determined using the XTT assay, and it was shown that the dendrons were nontoxic either alone or in the presence of DNA. However, when administered with DNA and chloroquine, the most highly branched dendron did exhibit some cytotoxicity. This paper elucidates the relationship between in vitro transfection efficiency and toxicity. While transfection efficiencies are modest, the low toxicity of the dendrons, both in their own right, and in the presence of DNA, provides encouragement that this type of building block, which has a relatively high affinity for DNA, will provide a useful starting point for the further synthetic development of more effective gene transfection agents.

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The motor points of the skeletal muscles, mainly of interest to anatomists and physiologists, have recently attracted much attention from researchers in the field of functional electrical stimulation. The muscle motor point has been defined as the entry point of the motor nerve branch into the epimysium of the muscle belly. Anatomists have pointed out that many muscles in the limbs have multiple motor points. Knowledge of the location of nerve branches and terminal nerve entry points facilitates the exact insertion and the suitable selection of the number of electrodes required for each muscle for functional electrical stimulation. The present work therefore aimed to describe the number, location, and distribution of motor points in the human forearm muscles to obtain optimal hand function in many clinical situations. Twenty three adult human cadaveric forearms were dissected. The numbers of primary nerves and motor points for each muscle were tabulated. The mean numbers and the standard deviation were calculated and grouped in tables. Data analyses were performed with the use of a statistical analysis package (SPSS 13.0). The proximal third of the muscle was the usual part of the muscle that received the motor points. Most of the forearm muscles were innervated from the lateral side and deep surface of the muscle. The information in this study may also be usefully applied in selective denervation procedures to balance muscles in spastic upper limbs. Copyright © 2007 Via Medica.

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This case describes a qualitative social science research project that was conducted in 2009 and that examined the experiences of recent migrants to Northern Ireland. While background to the research and key findings are presented, the topic forms a backdrop to the case. The following aspects of the study are presented: the theoretical context; formulating the research question, design and methodology; key methodological issues; data collection and analysis; project dissemination; and research funding and reporting. The case pays particular attention to the needs and impact of different groups including the researcher, the funding body, the researcher’s employer and the researched. The significance of access, language and ethics to this study are examined. Finally, the way in which the research unfolded in an often-unpredictable way throughout the implementation process is highlighted in the narrative.