Great Changes (great + change)

Distribution by Scientific Domains

Selected Abstracts

Social and Ecological Structures Supporting Adolescent Connectedness to School: A Theoretical Model

Stacey K. Waters MSc
ABSTRACT BACKGROUND: Adolescence is a time of great change. For most young people, this is a healthy and happy experience; however, for some it is characterized by many health, social, and academic challenges. A student's feeling of connectedness to school helps meet these challenges. Little is known, however, about the school characteristics that promote this connection and, more importantly, how this connection occurs. This article reviews the connectedness literature and integrates health promotion, adolescent development, and ecological frameworks to describe how a school context fosters this connection. METHOD: A systematic search and review process was used to retrieve scholarly articles pertaining to the research topic. RESULTS: Each retrieved article was summarized, and a subsequent model was developed to define a school ecology and describe how this ecology influences a student's need to feel connected to school and the positive influence this connection has on adolescent health and well-being. CONCLUSIONS: Integrating developmental, ecological, and health promotion intervention theories and frameworks assists in the identification of interpersonal and organizational aspects of a school environment, which satisfy an individual's needs to feel autonomous, competent, and connected, and to improve health and well-being outcomes for adolescents. [source]

The 29°N latitudinal line: an important division in the Hengduan Mountains, a biodiversity hotspot in southwest China

Da-Cai Zhang
This paper aimed to explore the division of the southern and northern Hengduan Mountains based on gradients in species similarity and richness, and to analyze species richness in each sub-region. The Hengduan Mountain region was divided into nine latitudinal belts using one degree of latitude to define the belt after which distribution of seed plants within each latitudinal belt was recorded. Latitudinal patterns of species similarity were measured using the Jaccard similarity index for each pair of adjacent latitudinal belts. Non-metric multidimentional scaling (NMDS) was also used to analyze the similarity in species composition among the nine latitudinal belts. The latitudinal pattern of species similarity and the NMDS ordination both showed a great change in species composition across the 29°N latitudinal line, essentially dividing the Hengduan Mountain region into southern and northern sub-regions. Species richness, shown by the c-value of the species,area power function, and species,area ratio along a latitudinal gradient both showed a sharp decrease across the latitudinal belt from 29°0, to 29°59,N. The southern sub-region occupied 40% of the total area of the Hengduan Mountain region, but contained more than 80% of all the seed plants in the region. The higher species richness and endemism in the southern sub-region showed it to be the core of the Hengduan biodiversity hotspot, a result not unexpected because of the greater extremes of topography and wider diversity of habitats in the southern portion. [source]

In times of great change, there is also great consistency

Dr Maureen Coombs MBE
No abstract is available for this article. [source]

Transitioning from brick layer to cathedral builder: Performance consulting and the power of one

Darlene Van Tiem CPT
In this time of great change, there are unprecedented opportunities for performance consultants to influence organizations to tie projects to Mega outcomes. To accomplish this, we must expand our thinking and view ourselves as transitioning from a focus on models, techniques, and interventions to a focus on improving a company's financial condition, saving jobs, and having an impact on the local economy. This article describes how four certified performance technologist standards can be applied to make this transition. [source]

Changes in the Labor Market and Occupational Prestige Scores

Junsuke Hara
Abstract, In spite of the great changes in the structures of industry as well as work and occupation in postwar Japan as a result of rapid industrialization, occupational prestige scores as an index of people's evaluation of occupations did not reveal the corresponding changes. They maintained consistent stability since the mid 1950s aside from parallel upward movements, which might be a result of the permeation of an egalitarian ideology. Three kinds of occupational prestige scores calculated from data in the SSM survey of 1955, 1975 and 1995 had very high correlation with each other. The scores also showed a strong correlation between levels of education and income for each occupation, and no relation with labor market situation. And the unchanged order of occupations in Japan might be one of the reasons for the stability. The fact that people's evaluation of occupations revealed by prestige scores has scarcely changed and such scores has been associated with differences in the level of education makes us suspect that Japan's "credentialism" might be weakened in the near future. [source]

Accident not intention: Llyn Cerrig Bach, Isle of Anglesey, Wales,site of an Iron Age shipwreck

Owain T. P. Roberts
The assemblage recovered fortuitously from Llyn Cerrig Bach in 1942 has been assumed without evidence to be the result of a Late Iron Age casting of votive offerings into that lake. The circumstances of its recovery and a consideration of the natural forces that have worked great changes to the coastline of south-west Anglesey suggest an alternative origin for the assemblage, that of its being the remains of cargo from a trading vessel lost about 50 BC. [source]

The Role of Fish Communities in Water Quality Management of a Large Shallow Lake

István Tátrai
Abstract Management measures of Lake Balaton such as wetland reconstruction at the main inflow to the lake along with the "unplanned" commercial fishery led to great changes in the density and biomass of fish populations. There was no significant difference in CPUE data between the two, eastern and western, basins. Biomass of total fish stock in Lake Balaton has decreased substantially, 2,3 times between 1991,1999, and ranges between 120,194 kg ha,1. Bottom-up effects are more important than the top-down effects due to the impact of internal nutrient load. Changes in the biomass and thus the activity of omnivorous fish in the lake lowered the intensity of various indirect effects and feedback mechanisms causing changes in the nutrient metabolism of the lake. Intensified fishery effort in Lake Balaton did not result in an increased stock of piscivores. The ratio of piscivores and omnivores remained at 5% during the whole study period. Despite this low piscivores to omnivores ratio, the water quality has improved in all basins. [source]

Interfacial structure of poly(methyl methacrylate)/TiO2 nanocomposites prepared through photocatalytic polymerization

Jiao Wang
Abstract Poly(methyl methacrylate)/TiO2 nanocomposites have been prepared by the polymerization with photoexcited TiO2 nanoparticles as initiator. To reveal the interfacial structure, the composites obtained are investigated by FTIR and XPS analysis. The bound PMMA displays triply split IR bands attributed to the carbonyl stretching mode, meanwhile great changes also occur in the IR range closely related to the conformation of PMMA. Based on the area of the nonassociated and associated PMMA carbonyl stretching peaks in the FTIR spectrum, it is calculated out that the bound PMMA is constituted of 70% repeating units in nonassociated state and 30% units associated to TiO2 inorganic nanoparticles. Moreover, XPS analysis show that Ti2p doublet of the composites shift to lower binding energy by 1.0 eV, indicating the interaction between Ti atoms of TiO2 and oxygen atoms of PMMA. According to the observation that the interaction involves both carboxyl and carbonyl groups of PMMA, a bidentate complex is approved. In addition, compared with the extracted PMMA, certain backbone chains of bound PMMA have to change their rotational conformations from gauche to trans so as to bond to the surface active centers at TiO2 nanoparticles. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]

Forty-five years in climatology,a personal odyssey

This article presents a personal perspective on an academic and research vocation spanning a period of over 45 years. It starts with my early involvement in geography and climatology and terminates with my recent experience in a large interdisciplinary research venture. The presentation highlights, with specific examples, the importance of mentors. Also emphasized is the indispensable input of colleagues and graduate students to successful research endeavours. Most of my career has been centred on McMaster University, and I naturally draw on my experiences there. There have been great changes in the research world over the past few decades. Although the number of faculty and graduate students at McMaster remained relatively constant, the research output per person more than doubled. This is attributed in large part to the accelerating technological advancements in our ability to measure and our ability to process and manipulate data. In the environmental sciences, this has revolutionized the spatial and temporal scope of the scientific questions that can be addressed. Such major changes have stimulated a marked trend towards interdisciplinary research that has evolved from mainly wishful talking to active pursuit in a search to understand complex environmental interactions. Important among these is gaining insights into the processes and feedbacks driving climate change, whether natural or anthropologically induced. Equally important is gaining an understanding of the potential impacts resulting from climate change. My perception of my successes, failures and near misses divides chronologically into three periods that cover research in the early years, research in the central subarctic and research in the Mackenzie River Basin. Quarante-cinq ans en climatologie , une odyssée personnelle Cet article propose un regard personnel sur une carrière universitaire et en recherche échelonnée sur plus de 45 ans, de mes premières contributions à la géographie et la climatologie à mes expériences actuelles au sein d'un projet de recherche interdisciplinaire. L'importance du rôle des mentors est illustrée par des exemples. Le concours indispensable apporté par les collègues et les étudiants des cycles supérieurs au succès des démarches de recherche est également souligné. La majeure partie de mes expériences professionnelles s'est déroulée à l'université McMaster et c'est pourquoi il est naturel pour moi d'y faire référence. De grands changements ont bouleversé le monde de la recherche depuis quelques décennies. Malgré le fait que le nombre de professeurs et d'étudiants des cycles supérieurs soit demeuré relativement stable, la publication de résultats de recherche par personne a plus que doublé. Ceci est attribuable en grande partie au développement rapide des technologies qui nous permettent d'évaluer, de traiter et de manipuler les données. Nous assistons donc à une révolution dans le domaine des sciences environnementales au niveau des dimensions spatiales et temporelles des questions scientifiques que nous pouvons aborder. Ces changements d'envergure alimentent une tendance nette en faveur de la recherche interdisciplinaire qui a évolué d'un v,u pieux à une entreprise active visant à comprendre les interactions environnementales d'un haut niveau de complexité. Il est essentiel de mieux prendre conscience des processus et rétroactions qui interviennent dans les changements climatiques naturels ou d'origine anthropiques. Il est aussi très important de mieux comprendre les effets induits par les changements climatiques. Ma manière de percevoir mes réussites, échecs et quasi-succès se divise chronologiquement en trois époques: les recherches durant les premières années, les recherches menées dans le subarctique, et les recherches sur le bassin du fleuve Mackenzie. [source]

Temporal-Spatial Structure of Intraplate Uplift in the Qinghai-Tibet Plateau

Dewei LI
Abstract: The intraplate uplift of the Qinghai-Tibet Plateau took place on the basis of breakup and assembly of the Precambrian supercontinent, and southward ocean-continent transition of the Proto-, Paleo-, Meso- and Neo-Tethys during the Caledonian, Indosinian, Yanshanian and Early Himalayan movements. The intraplate tectonic evolution of the Qinghai-Tibet Plateau underwent the early stage of intraplate orogeny characterized by migrational tectonic uplift, horizontal movement and geological processes during 180,7 Ma, and the late stage of isostatic mountain building characterized by pulsative rapid uplift, vertical movement and geographical processes since 3.6 Ma. The spatial-temporal evolution of the intraplate orogeny within the Qinghai-Tibet Plateau shows a regular transition from the northern part through the central part to the southern part during 180,120 Ma, 65,35 Ma, and 25,7 Ma respectively, with extensive intraplate faulting, folding, block movement, magmatism and metallogenesis. Simultaneous intraplate orogeny and basin formation resulted from crustal rheological stratification and basin-orogen coupling that was induced by lateral viscous flow in the lower crust. This continental dynamic process was controlled by lateral flow of hot and soft materials within the lower crust because of slab dehydration and melted mantle upwelling above the subducted plates during the southward Tethyan ocean-continent transition processes or asthenosphere diapirism. Intraplate orogeny and basin formation were irrelevant to plate collision. The Qinghai-Tibet Plateau as a whole was actually formed by the isostatic mountain building processes since 3.6 Ma that were characterized by crust-scale vertical movement, and integral rapid uplift of the plateau, accompanied by isostatic subsidence of peripheral basins and depressions, and great changes in topography and environment. A series of pulsative mountain building events, associated with gravity equilibrium and isostatic adjustment of crustal materials, at 3.6 Ma, 2.5 Ma, 1.8,1.2 Ma, 0.9,0.8 Ma and 0.15,0.12 Ma led to the formation of a composite orogenic belt by unifying the originally relatively independent Himalayas, Gangdisê, Tanghla, Longmenshan, Kunlun, Altyn Tagh, and Qilian mountains, and the formation of the complete Qinghai-Tibet Plateau with a unified mountain root after Miocene uplift of the plateau as a whole. [source]

Writing through time: longitudinal studies of the effects of new technology on writing

James Hartley
This paper contributes to the discussion about the effects of new technology on writing by assessing whether or not people's writing styles and ways of thinking change when new technologies are introduced. The writing styles of the three authors, prolific writers in their own fields, were assessed by comparing materials written by each author over a thirty-year period. During this time there were, for each author, great changes in the ways that they used new technology to help them to write. Nonetheless, the results indicated that, although the writing styles of each author differed from each other, their individual styles were remarkably consistent over time. These results thus suggest that although the new technologies may change the ways that individual writers work, they do not alter the styles of their resulting products. [source]

When brains expand: mind and the evolution of cortex

Matthew T. K. Kirkcaldie
Objective:, To critically examine the relationship between evolutionary and developmental influences on human neocortex and the properties of the conscious mind it creates. Methods:, Using PubMed searches and the bibliographies of several monographs, we selected 50 key works, which offer empirical support for a novel understanding of the organization of the neocortex. Results:, The cognitive gulf between humans and our closest primate relatives has usually been taken as evidence that our brains evolved crucial new mechanisms somehow conferring advanced capacities, particularly in association areas of the neocortex. In this overview of neocortical development and comparative brain morphometry, we propose an alternative view: that an increase in neocortical size, alone, could account for novel and powerful cognitive capabilities. Other than humans' very large brain in relation to the body weight, the morphometric relations between neocortex and all other brain regions show remarkably consistent exponential ratios across the range of primate species, including humans. For an increase in neocortical size to produce new abilities, the developmental mechanisms of neocortex would need to be able to generate an interarchy of functionally diverse cortical domains in the absence of explicit specification, and in this respect, the mammalian neocortex is unique: its relationship to the rest of the nervous system is unusually plastic, allowing great changes in cortical organization to occur in relatively short periods of evolution. The fact that even advanced abilities like self-recognition have arisen in species from different mammalian orders suggests that expansion of the neocortex quite naturally generates new levels of cognitive sophistication. Our cognitive and behavioural sophistication may, therefore, be attributable to these intrinsic mechanisms' ability to generate complex interarchies when the neocortex reaches a sufficient size. Conclusion:, Our analysis offers a parsimonious explanation for key properties of the human mind based on evolutionary influences and developmental processes. This view is perhaps surprising in its simplicity, but offers a fresh perspective on the evolutionary basis of mental complexity. [source]