906 resultados para Escalonamento multidimensional


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The research analyzes product quality from a customer perspective in the case of the wood products industry. Of specific interest is to understand better how environmental quality is perceived from a customer perspective. The empirical material used comprises four data-sets from Finland, Germany and the UK, collected during 1992 2004. The methods consist of a set of quantitative statistical analyses. The results indicate that perceived quality from a customer perspective can be presented using a multidimensional and hierarchical construct with tangible and intangible dimensions, that is common to different markets and products. This applies in the case of wood products but also more generally at least for some other construction materials. For wood products, tangible product quality has two main sub-dimensions: technical quality and appearance. For product intangibles, a few main quality dimensions seem be detectable: Quality of intangibles related to the physical product, such as environmental issues and product-related information, supplier-related characteristics, and service and sales personnel behavior. Environmental quality and information are often perceived as being inter-related. Technical performance and appearance are the most important considerations for customers in the case of wood products. Organizational customers in particular also clearly consider certain intangible quality dimensions to be important, such as service and supplier reliability. The high technical quality may be considered as a license to operate , but product appearance and intangible quality provide potential for differentiation for attracting certain market segments. Intangible quality issues are those where Nordic suppliers underperform in comparison to their Central-European competitors on the important German markets. Environmental quality may not have been used to its full extent to attract customers. One possibility is to increase the availability of the environment-related information, or to develop environment-related product characteristics to also provide some individual benefits. Information technology provides clear potential to facilitate information-based quality improvements, which was clearly recognized by Finnish forest industry already in the early 1990s. The results indeed indicate that wood products markets are segmented with regard to quality demands

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Some theorems derived recently by the authors on the stability of multidimensional linear time varying systems are reported in this paper. To begin with, criteria based on Liapunov�s direct method are stated. These are followed by conditions on the asymptotic behaviour and boundedness of solutions. Finally,L 2 andL ? stabilities of these systems are discussed. In conclusion, mention is made of some of the problems in aerospace engineering to which these theorems have been applied.

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The major changes that have been witnessed in today's workplaces are challenging the mental well-being of employed people. Stress and burnout are considered to be modern epidemics, and their importance to physical health and work ability has been acknowledged world-wide. The aim of the thesis was to study the concept of burnout as a process proceeding from its antecedents, through the development of the syndrome, and to its outcomes. Several work-related factors considered antecedents of burnout were studied in different occupational groups. The syndrome of burnout is seen as consisting of three dimensions - exhaustion, cynicism and lack of professional efficacy - and different alternatives for the sequential development of these dimensions were tested. Furthermore, several indicators of the severely detrimental health and work ability outcomes of burnout were investigated in a longitudinal study design. The research questions were as follows. 1) Is burnout, as measured with the Maslach Burnout Inventory - General Survey (MBI-GS), a three-dimensional construct and how invariant is the factorial structure across occupations (Finnish) and national samples (Finnish, Swedish and Dutch)? How persistent is exhaustion over time? 2) What is the sequential process of burnout? Is it similar across occupations? How do work stressors relate to the process? 3) How does burnout relate to severe health consequences as well as temporary and chronic work disability according to hospitalization periods, sick-leave episodes and receiving disability pensions? The data were collected between 1986 and 2005. The population of the study consisted of respondents to a company-wide questionnaire survey carried out in 1996-1997 (N=9705, response rate 63%). The participants comprised 6025 blue-collar workers and 3680 white-collar workers. The majority were men (N=7494) and the average age was 43.7 years. In addition, a sample from the population had responded to a questionnaire survey in 1988, which was combined with the 1996 data to form panel data on 713 respondents. The register-based data were collected between 1986 and 2005 from 1) the company's occupational health services' records for a sample of respondents from the 1996 questionnaire survey (sick-leave data), 2) hospitalization records from the Hospital discharge register, and 3) disability pension records from the Finnish Centre for Pensions. These data were combined person by person with the 1996 questionnaire survey data with the help of personal identification numbers which were saved with the study numbers by the researchers. The results showed that burnout consists of three separate but correlating symptoms: exhaustion, cynicism and lack of professional efficacy. As a syndrome, burnout was strongly related to job stressors at work, and seemed to develop from exhaustion through cynicism to lack of professional efficacy in a similar manner among white-collar and blue-collar employees. The results also showed that exhaustion persisted even after eight years of follow-up but did not predict cynicism or lack of professional efficacy after that amount of time. Nor were job stressors longitudinally related to burnout. Longitudinal results were obtained for the severe health-related consequences of burnout. The investigated outcomes represented different phases of health deterioration ranging from sick-leaves and hospitalization periods to receiving work disability pensions. The results showed that burnout syndrome, and its elements of exhaustion and cynicism, were related to future mental and cardiovascular disorders as indicated by hospitalization periods. Burnout was also related to future sick-leave periods due to mental, cardiovascular and musculoskeletal disorders. Of the separate elements, exhaustion was related to the same three categories of disorder, cynicism to mental, musculoskeletal and digestive disorders, and lack of professional efficacy to mental and musculoskeletal disorders. Burnout also predicted receiving disability pensions due to mental and musculoskeletal disorders among initially healthy subjects. Exhaustion was related to receiving disability pensions even when self-reported chronic illness was taken into account. The results suggest that burnout is a multidimensional, chronic, work-related syndrome, which may have serious consequences for health and work ability.

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In daily life, rich experiences evolve in every environmental and social interaction. Because experience has a strong impact on how people behave, scholars in different fields are interested in understanding what constitutes an experience. Yet even if interest in conscious experience is on the increase, there is no consensus on how such experience should be studied. Whatever approach is taken, the subjective and psychologically multidimensional nature of experience should be respected. This study endeavours to understand and evaluate conscious experiences. First I intro-duce a theoretical approach to psychologically-based and content-oriented experience. In the experiential cycle presented here, classical psychology and orienting-environmental content are connected. This generic approach is applicable to any human-environment interaction. Here I apply the approach to entertainment virtual environments (VEs) such as digital games and develop a framework with the potential for studying experiences in VEs. The development of the methodological framework included subjective and objective data from experiences in the Cave Automatic Virtual Environment (CAVE) and with numerous digital games (N=2,414). The final framework consisted of fifteen factor-analytically formed subcomponents of the sense of presence, involvement and flow. Together, these show the multidimensional experiential profile of VEs. The results present general experiential laws of VEs and show that the interface of a VE is related to (physical) presence, which psychologically means attention, perception and the cognitively evaluated realness and spatiality of the VE. The narrative of the VE elicits (social) presence and involvement and affects emotional outcomes. Psychologically, these outcomes are related to social cognition, motivation and emotion. The mechanics of a VE affect the cognitive evaluations and emotional outcomes related to flow. In addition, at the very least, user background, prior experience and use context affect the experiential variation. VEs are part of many peoples lives and many different outcomes are related to them, such as enjoyment, learning and addiction, depending on who is making the evalua-tion. This makes VEs societally important and psychologically fruitful to study. The approach and framework presented here contribute to our understanding of experiences in general and VEs in particular. The research can provide VE developers with a state-of-the art method (www.eveqgp.fi) that can be utilized whenever new product and service concepts are designed, prototyped and tested.

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Financial Help Alone? Financial help as an exponent of professional diaconal work One essential form of helping people in the Evangelical Lutheran Church s diaconal work is providing economic aid. It can be seen as work which is in accordance with the spirit of the Church Order (4:3). One of the tasks of diaconal work, determined by the Church Order, is to help those whose distress is the greatest and who have no other source of help. This financial support has become a permanent and essential working method, which has also created tension of various kinds. Financial support has been criticized, especially when the support has been used to fill a gap in the social services provided by the government. It has been argued that diaconal work has been forced to take on responsibility for tasks that belong to the welfare state. The tensions involved in the financial support of diaconal work do not only concern the patching up and supplementing of the deficiencies in the welfare state s services but also the question of diaconal workers self-understanding of financial support and how it relates to their professionalism. In this thesis, I examine the experiences and visions diaconal workers have concerning financial support in their work with clients. The viewpoint of my work is the diaconal workers own experiences and interpretations of the meaning of financial support in customer service. In the articles of my thesis, I examined the meanings that diaconal workers gave to financial support in the aspects of work motivation, empowerment, expertise and tensions. The research material of my articles consists of three different data, which are theme interviews from diaconal workers, a survey from diaconal workers of Espoo and a diaconal barometer of 2009. I have analysed the theme interviews and the survey using qualitative content analysis. The results of my articles showed that diaconal workers motivation in tasks concerning economic aid was sustained by the nature and spiritual aspects of support activities. Work that supported empowerment through financial assistance meant influencing the client s personal life, community and local ties and structural circumstances of the surrounding society. Diaconal workers expertise in financial support work can be characterised as horizontal, which means that the expertise was built on acknowledging the client s dignity, the uniqueness of the client s life situation and listening to the client s own voice. Diaconal workers were also experts in community and area-based work. The tensions in financial support work are linked to its unofficial and undefined role in the field of social welfare and the inability of other aiding parties to respond to their duties. The results of my thesis on the experiences and visions of financial support reveal that it is multilateral and multidimensional. Diaconal workers used financial support to help the clients, taking into account their individual, communal, social and spiritual context. The professionalism of this financial support is reflectively related to the client s need of help and the spontaneity and unexpectedness of the situation. Support work was deeply bound to diaconal workers experiences of spirituality as the basic value in their work, the foundation of their idea of humanity and their method of helping others. In different tasks of financial support diaconal workers balanced between traditional, individual client work based on caritas and working methods which are based on supporting the individual s empowerment and active citizenship, as in postmodern social work. Diaconal workers experiences of financial support illustrated the transition or turning point in the professionalism of diaconal work, which involves finding one s own, stronger and clearer professional identity than earlier with respect to other helpers in society. Creating a unique identity is part of the empowerment process of diaconal work, in which it must define its professional role by itself. In postmodern pluralism and the fragmented context of diaconal activities, the question arose as to whether the spiritual traditions and traditional values of diaconal work support the modifications and adaptations needed in new, unpredictable situations. Diaconal work is said to be fast to react, able to predict changes and adapt to those changes. To preserve its sensitive reactive ability, also in the complex postmodern world, it must retain its own views and orientations. Otherwise, the distinctive values and traditions of diaconal work might sustain static diaconal work, employee-centeredness and a smug attitude when defining beneficiaries and needs, which highlights the paternalism of diaconal work. Such paternalism may complicate the progress of working methods which are based on empowerment and citizenship.

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In meteorology, observations and forecasts of a wide range of phenomena for example, snow, clouds, hail, fog, and tornados can be categorical, that is, they can only have discrete values (e.g., "snow" and "no snow"). Concentrating on satellite-based snow and cloud analyses, this thesis explores methods that have been developed for evaluation of categorical products and analyses. Different algorithms for satellite products generate different results; sometimes the differences are subtle, sometimes all too visible. In addition to differences between algorithms, the satellite products are influenced by physical processes and conditions, such as diurnal and seasonal variation in solar radiation, topography, and land use. The analysis of satellite-based snow cover analyses from NOAA, NASA, and EUMETSAT, and snow analyses for numerical weather prediction models from FMI and ECMWF was complicated by the fact that we did not have the true knowledge of snow extent, and we were forced simply to measure the agreement between different products. The Sammon mapping, a multidimensional scaling method, was then used to visualize the differences between different products. The trustworthiness of the results for cloud analyses [EUMETSAT Meteorological Products Extraction Facility cloud mask (MPEF), together with the Nowcasting Satellite Application Facility (SAFNWC) cloud masks provided by Météo-France (SAFNWC/MSG) and the Swedish Meteorological and Hydrological Institute (SAFNWC/PPS)] compared with ceilometers of the Helsinki Testbed was estimated by constructing confidence intervals (CIs). Bootstrapping, a statistical resampling method, was used to construct CIs, especially in the presence of spatial and temporal correlation. The reference data for validation are constantly in short supply. In general, the needs of a particular project drive the requirements for evaluation, for example, for the accuracy and the timeliness of the particular data and methods. In this vein, we discuss tentatively how data provided by general public, e.g., photos shared on the Internet photo-sharing service Flickr, can be used as a new source for validation. Results show that they are of reasonable quality and their use for case studies can be warmly recommended. Last, the use of cluster analysis on meteorological in-situ measurements was explored. The Autoclass algorithm was used to construct compact representations of synoptic conditions of fog at Finnish airports.

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Hostility is a multidimensional construct having wide effects on society. In its different forms, hostility is related to a large array of social and health problems, such as criminality, substance abuse, depression, and cardiovascular risks. Identifying and tackling early-life factors that contribute to hostility may have public health significance. Although the variance in hostility is estimated to be 18-50 percent heritable, there are significant gaps in knowledge regarding the molecular genetics of hostility. It is known that a cold and unsupportive home atmosphere in childhood predicts a child s later hostility. However, the long-term effects of care-giving quality on hostility in adulthood and the role of genes in this association are unclear. The present dissertation is part of the ongoing population-based prospective Young Finns study, which commenced in 1980 with 3596 3-18-year-old boys and girls who were followed for 27 years. The specific aims of the dissertation were first to study the antecedents of hostility by looking at 1) the genetic background, 2) the early environmental predictors, and 3) the gene environment interplay behind hostility. As a second aim, the thesis endeavored to examine 4) the association between hostility and cardiovascular risks, and 5) the moderating effect of demographic factors, such as gender and socioeconomic status, on this association. The study found potential gene polymorphisms from chromosomes 7, 14, 17, and 22 suggestively associated with hostility. Of early environmental influences, breastfeeding and early care-giving were found to predict hostility in adulthood. In addition, a serotonin receptor 2A polymorphism rs6313 moderated the effect of early care-giving on later hostile attitudes. Furthermore, hostility was shown to predict cardiovascular risks, such as metabolic syndrome and inflammation. Finally, parental socioeconomic status was found to moderate the association between anger and early atherosclerosis. The new genetic and early environmental antecedents of hostility identified in this research may help in understanding the development of hostility and its health risks, and in planning appropriate prevention. The significance of early influences on this development is stressed. Although the markers studied are individual- and family-related factors, these may be influenced at the societal level by giving accurate information to all individuals concerned and by improving the societal circumstances.

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Simple expansion chambers, the simplest of the muffler configurations, have very limited practical application due to the presence of periodic troughs in the transmission loss spectrum which drastically lower the overall transmission loss of the muffler. Tuned extended inlet and outlet can be designed to nullify three-fourths of these troughs, making use of the plane wave theory. These cancellations would not occur unless one altered the geometric lengths for the extended tube in order to incorporate the effect of evanescent higher-order modes (multidimensional effect) through end corrections or lumped inertance approximation at the area discontinuities or junctions. End corrections of the extended inlet and outlet have been studied by several researchers. However the effect of wall thickness of the inlet/outlet duct on end correction has not been studied explicitly. This has significant effect on the tuning of an extended inlet/outlet expansion chamber. It is investigated here experimentally as well as numerically (through use of 3-D FEM software) for stationary medium. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.

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High food prices can be a barrier to healthy eating because some of the food products may be perceived as expensive. Understanding the role of price in food purchase situations is important, but only a few studies document attitudes towards expensiveness or cheapness in foods. In this thesis, the role of food price in food choice and consumers attitudes towards food prices were investigated and the aim was to measure the food price attitudes. Food price attitudes were hypothesized to have an impact on consumers willingness to pay judgements and their willingness to buy premium-priced food products. First, using qualitative data consisting of 40 thematic interviews the experiences of the expensiveness and cheapness in foods were explored by using functional food products as a target product category. Second, a Food Price Attitude Scale was developed using four quantitative surveys representing Finnish consumers (2001 N=1158; 2002 N=1156; 2004a N=1113; 2004b N=1027). Food price attitudes were confirmed to compose a multidimensional construct and consumers may perceive positive and negative attitudes towards both high and low food prices. Finnish consumers were clustered into four groups based on their food price attitudes. In the first group, 29% of respondents were negative towards high food prices and they were willing to seek low food prices, whereas respondents in another group (22%) were positive towards high food prices. Additionally, in the third group consumers (17%) were willing to pay for high quality but still looked for low food prices. In the fourth group, consumers (32%) were willing to look for low food prices, unwilling to pay for high quality, but high-priced food was appreciated if offered to others. It was found in qualitative data that consumers willingness to accept high prices in foods was connected to price fairness and to justifications. Feelings of fairness or unfairness might be a core element of food price attitudes. Using quantitative methods, it was confirmed that positive attitudes towards high food prices in terms of high quality enhanced consumers willingness to buy food products with certain benefits (e.g., a health claim). Additionally, the favourable attitude towards low food prices lowered the willingness to pay estimates. This type of tendency, however, can create a possible bias in small convenient samples. In the food price-related research, it is advisable to take into account food price attitudes as possible background variables. The Food Price Attitude Scale needs further development to increase construct validity even though, in the present study, it was shown to be a reliable measure with good predictive and discriminant validity. The theoretical and managerial implications of the results for a better understanding of the role of price in consumers food purchases are discussed.

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M.A. (Educ.) Anu Kajamaa from the University of Helsinki, Center for Research on Activity, Development and Learning (CRADLE), examines change efforts and their consequences in health care in the public sector. The aim of her academic dissertation is, by providing a new conceptual framework, to widen our understanding of organizational change efforts and their consequences and managerial challenges. Despite the multiple change efforts, the results of health care development projects have not been very promising, and many developmental needs and managerial challenges exist. The study challenges the predominant, well-framed health care change paradigm and calls for an expanded view to explore the underlying issues and multiplicities of change efforts and their consequences. The study asks what kind of expanded conceptual framework is needed to better understand organizational change as transcending currently dominant oppositions in management thinking, specifically in the field of health care. The study includes five explorative case studies of health care change efforts and their consequences in Finland. Theory and practice are tightly interconnected in the study. The methodology of the study integrates the ethnography of organizational change, a narrative approach and cultural-historical activity theory. From the stance of activity theory, historicity, contradictions, locality and employee participation play significant roles in developing health care. The empirical data of the study has mainly been collected in two projects, funded by the Finnish Work Environment Fund. The data was collected in public sector health care organizations during the years 2004-2010. By exploring the oppositions between distinct views on organizational change and the multi-site, multi-level and multi-logic of organizational change, the study develops an expanded, multidimensional activity-theoretical framework on organizational change and management thinking. The findings of the study contribute to activity theory and organization studies, and provide information for health care management and practitioners. The study illuminates that continuous development efforts bridged to one another and anchored to collectively created new activity models can lead to significant improvements and organizational learning in health care. The study presents such expansive learning processes. The ways of conducting change efforts in organizations play a critical role in the creation of collective new practices and tools and in establishing ownership over them. Some of the studied change efforts were discontinuous or encapsulated, not benefiting the larger whole. The study shows that the stagnation and unexpected consequences of change efforts relate to the unconnectedness of the different organizational sites, levels and logics. If not dealt with, the unintended consequences such as obstacles, breaks and conflicts may stem promising change and learning processes.

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"I will soon understand." The House Planning Program as an Enhancer of Pupils´ Thinking Skills and Learning in Home Economics at Comprehensive School The aim of the research was to build a study program for home economics education in order to enhance pupils´ thinking skills. The program was based on the intervention programs or strategies known as Cognitive Acceleration (CA), which are founded on the theories of Jean Piaget, Lev Vygotsky, and Reuven Feuerstein. In addition, Carl Bereiter s theory of knowledge building was integrated to the research. The viewpoint of home economics was based on the multidimensional foundation of home economics science, particularly household technology and house planning. I first analyzed the kind of body of knowledge home economics science and home economics education provides for enhancing thinking skills in home economics. For the study, a CATE (Cognitive Acceleration through Technology Education) program was adapted and modified and a House Planning program was created for home economics classes. The house planning program consisted of five lessons during which pupils learned how to make functional floor plans as well as choose furniture, household appliances and materials for the home. In order to obtain the required data, various classroom experiments were arranged in 2005 with grade 9 pupils at a comprehensive school in Helsinki. All the experiments were videotaped, and five hours of the videotaped material was edited and transcribed for closer examination. The material consisted of all the video-recorded activity of the selected study group. Interaction study and content analysis were used to analyze the data. Following the experiments, a small survey was conducted to solicit pupils´ and teacher´s opinions of the program. The analysis sheds light on the nature of pupils´ interaction and knowledge building in small group activity. Special attention was given to tracking pupils´ interaction during the socalled construction zone activity. The models and qualities of teacher´s aid and support during the lessons were examined as well. The results revealed the versatility of the pupils social interaction and common knowledge building that occurred during the small group activity. The pupils discussions, including their arguments, their sharing of ideas, and the multiple perspectives that emerged reflected home economics knowledge building. The construction zone activity appeared through expressions of cognitive conflict and metacognition. Cognitive conflict was evident in the pupils´ words and involved questioning, doubting and disputing. The metacognitive activity emerged by thinking aloud, choosing the strategies, and negotiating the results. The pupils also coordinated their activity, allocated the responsibility, and systematized their work. The teacher assisted by preparing new themes for the pupils and by participating in the small group work. The teacher´s help during the small group sessions strengthened the pupils activity in the construction zone. The results showed that one can utilize the wide multidisciplinary basis of home economics, which includes scientific knowledge but also the knowledge derived from practical activity and experience. In this study practical activity was undertaken as a planning project the result of which was a plan or a new vision for the house planning situation. The study showed that the House Planning program was able to enhance the pupils´ social interaction and collaboration. The learning environment challenged the pupils in a way that could be a gateway to further developing their thinking skills. The method of analysis created in the study could be a potential tool for examining social interaction, construction zone activity, and knowledge building in other learning environments as well. Key words: home economics, house planning, classroom experiment, thinking skills,cognitive conflict, metacognition, social interaction, knowledge building

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The catalytic conversion of adenosine triphosphate (ATP) and adenosine monophosphate (AMP) to adenosine diphosphate (ADP) by adenylate kinase (ADK) involves large amplitude, ligand induced domain motions, involving the opening and the closing of ATP binding domain (LID) and AMP binding domain (NMP) domains, during the repeated catalytic cycle. We discover and analyze an interesting dynamical coupling between the motion of the two domains during the opening, using large scale atomistic molecular dynamics trajectory analysis, covariance analysis, and multidimensional free energy calculations with explicit water. Initially, the LID domain must open by a certain amount before the NMP domain can begin to open. Dynamical correlation map shows interesting cross-peak between LID and NMP domain which suggests the presence of correlated motion between them. This is also reflected in our calculated two-dimensional free energy surface contour diagram which has an interesting elliptic shape, revealing a strong correlation between the opening of the LID domain and that of the NMP domain. Our free energy surface of the LID domain motion is rugged due to interaction with water and the signature of ruggedness is evident in the observed root mean square deviation variation and its fluctuation time correlation functions. We develop a correlated dynamical disorder-type theoretical model to explain the observed dynamic coupling between the motion of the two domains in ADK. Our model correctly reproduces several features of the cross-correlation observed in simulations. (C) 2011 American Institute of Physics. doi:10.1063/1.3516588]

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Taman tutkielman tarkoituksena oli selvittaa metsikon rakenteen seka hakkuiden vaikutuksia pintakasvillisuuden lajikoostumukseen ja biomassaan Etela-Suomen lehtomaisilla, tuoreilla ja kuivahkoilla kankailla. Aineistona tassa tyossa on 8. valtakunnan metsien inventoinnin yhteydessa vuosina 1985–86 metsaluonnon ja ympariston tilan seurantaa varten perustetuista noin 3 000 pysyvasta koealasta poimittu otos. Pintakasvillisuuden lajisto muuttuu metsikon kehitysvaiheen mukaan. Hakkuu on huomattava hairio, joka aiheuttaa nopeita ja suuria muutoksia pintakasvillisuudessa. Pintakasvillisuutta on tarkasteltu lahinna lajiryhmittain (heinat, ruohot, varvut, sammalet seka jakalat). Kunkin lajiryhman peittavyyden eroavaisuuksia testattiin varianssianalyysilla kun selittavana muuttujana ovat luokittain metsikon ika ja edellisesta hakkuusta kulunut aika. Lajikohtaisia tarkasteluja on sen sijaan tehty kasvillisuuden ordinaatioanalyyseilla. Tassa kaytetty ordinaatiomenetelma on epametrinen moniulotteinen skaalaus (Non-metric multidimensional scaling, NMDS), jonka avulla voidaan tehda paatelmia kasvillisuuden rakenteen ekologisesta vaihtelusta ymparistomuuttujien suhteen. Harvennus- ja avohakkuiden vaikutuksia pintakasvillisuuteen myos mallinnettiin lajiryhmittain kayttaen yleistettyja lineaarisia malleja (Generalized linear models). Lajiryhmien peittavyyksien kehitysta mallinnettiin puuston pohjapinta-alan funktiona. Metsikon ian kasvaessa heinien ja ruohojen osuus pienenee, kun taas varpujen ja sammalten osuus lisaantyy. Harvennushakkuiden vaikutukset ovat lievempia kuin avohakkuiden eivatka ne useimmiten aiheuttaneet tilastollisesti merkittavia muutoksia pintakasvillisuuden peittavyyksissa. Avohakkuu sen sijaan on voimakkaampi ja aiheuttaa merkittavia muutoksia. Heinia ja ruohoja esiintyy hakkuun jalkeen enemman ja vastaavasti sammalet ja varvut taantuvat. Kasvillisuuden kokonaispeittavyys ja biomassa ovat suurimmillaan hakkaamattomissa metsikoissa. Harvennushakkuun jalkeen peittavyys ja biomassa voi kuitenkin hetkellisesti olla suurimmillaan kun harvennuksesta on kulunut muutama vuosi. Yleistetyt lineaariset mallit kuvasivat pintakasvillisuuden kehitysta metsikon pohjapinta-alan funktiona luotettavasti. Malleja voidaan kayttaa myos ennustamaan miten pintakasvillisuus kehittyy avohakkuun jalkeen. Malleja voidaan soveltaa esimerkiksi laskettaessa pintakasvillisuuden sitoman hiilen maaraa eriikaisissa metsissa. Niiden avulla voidaan myos arvioida esimerkiksi avohakkuuta voimaperaisemman energiapuun korjuun vaikutuksia pintakasvillisuuden runsauteen.

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Multidimensional NMR studies of o-vanillin salicyloylhydrazone at various temperatures have been undertaken in deuterated dimethyl sulfoxide and its cryoprotective mixture in H2O and D2O, acetone and acetonitrile. The molecule is found to exist in two conformers in dimethyl sulfoxide and the cryoprotective mixture. The exchange between the two conformers has been detected from the two-dimensional experiments - information which is not easily obtainable from the normal one-dimensional spectra. Results in the different solvents are interpreted in terms of solvent-solute interactions.

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Electron transfer reactions in large molecules may often be coupled to both the polar solvent modes and the intramolecular vibrational modes of the molecule. This can give rise to a complex dynamics which may in some systems, like betaine, be controlled more by vibrational rather than by solvent effects. Additionally, a significant contribution from an ultrafast relaxation component in the solvation dynamics may enhance the complexity. To explain the wide range of behavior that has been observed experimentally, Barbara et al. recently proposed that a model of an electron transfer reaction should minimally consist of a low-frequency classical solvent mode (X), a low-frequency vibrational mode (Q), and a high-frequency quantum mode (q) (J. Phys. Chem. 1991, 96, 3728). In the present work, a theoretical study of this model is described. This study generalizes earlier work by including the biphasic solvent response and the dynamics of the low-frequency vibrational mode in the presence of a delocalized, extended reaction zone. A novel Green's function technique has been developed which allowed us to study the non-Markovian dynamics on a multidimensional surface. The contributions from the high-frequency vibrational mode and the ultrafast component in the non-Markovian solvent dynamics are found to be primarily responsible for the dramatic increase in charge transfer rate over the prediction of the classical theories that neglect both these factors. These, along with a large coupling between the reactant and the product states, may combine to render the electron transfer rate both very large and constant over a wide range of solvent relaxation rates. A study on the free energy gap dependence of the electron transfer rate reveals that the rates are sensitive to changes in the quantum frequency particularly when the free energy gap is very large.