886 resultados para Quantitative structure-property relationship


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UNLABELLED: Bone microarchitecture by high-resolution peripheral quantitative computed tomography (HR-pQCT) was assessed in adult patients with mild, moderate, and severe osteogenesis imperfecta (OI). The trabecular bone score (TBS), bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA), and dual X-ray and laser (DXL) at the calcaneus were likewise assessed in patients with OI. Trabecular microstructure and BMD in particular were severely altered in patients with OI. INTRODUCTION: OI is characterized by high fracture risk but not necessarily by low BMD. The main purpose of this study was to assess bone microarchitecture and BMD at different skeletal sites in different types of OI. METHODS: HR-pQCT was performed in 30 patients with OI (mild OI-I, n = 18 (41.8 [34.7, 55.7] years) and moderate to severe OI-III-IV, n = 12 (47.6 [35.3, 58.4] years)) and 30 healthy age-matched controls. TBS, BMD by DXA at the lumbar spine and hip, as well as BMD by DXL at the calcaneus were likewise assessed in patients with OI only. RESULTS: At the radius, significantly lower trabecular parameters including BV/TV (p = 0.01 and p < 0.0001, respectively) and trabecular number (p < 0.0001 and p < 0.0001, respectively) as well as an increased inhomogeneity of the trabecular network (p < 0.0001 and p < 0.0001, respectively) were observed in OI-I and OI-III-IV in comparison to the control group. Similar results for trabecular parameters were found at the tibia. Microstructural parameters were worse in OI-III-IV than in OI-I. No significant differences were found in cortical thickness and cortical porosity between the three subgroups at the radius. The cortical thickness of the tibia was thinner in OI-I (p < 0.001), but not OI-III-IV, when compared to controls. CONCLUSIONS: Trabecular BMD and trabecular bone microstructure in particular are severely altered in patients with clinical OI-I and OI-III-IV. Low TBS and DXL and their significant associations to HR-pQCT parameters of trabecular bone support this conclusion.

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Forensic laboratories mainly focus on the qualification and the quantitation of the illicit drug under analysis as both aspects are used for judiciary purposes. Therefore, information related to cutting agents (adulterants and diluents) detected in illicit drugs is limited in the forensic literature. This article discusses the type and frequency of adulterants and diluents detected in more than 6000 cocaine specimens and 3000 heroin specimens, confiscated in western Switzerland from 2006 to 2014. The results show a homogeneous and quite unchanging adulteration for heroin, while for cocaine it could be characterised as heterogeneous and relatively dynamic. Furthermore, the results indicate that dilution affects more cocaine than heroin. Therefore, the results provided by this study tend to reveal differences between the respective structures of production or distribution of cocaine and heroin. This research seeks to promote the systematic analysis of cutting agents by forensic laboratories. Collecting and processing data related to the presence of cutting agents in illicit drug specimens produces relevant information to understand and to compare the structure of illicit drug markets.

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BackgroundBipolar disorder is a highly heritable polygenic disorder. Recent enrichment analyses suggest that there may be true risk variants for bipolar disorder in the expression quantitative trait loci (eQTL) in the brain.AimsWe sought to assess the impact of eQTL variants on bipolar disorder risk by combining data from both bipolar disorder genome-wide association studies (GWAS) and brain eQTL.MethodTo detect single nucleotide polymorphisms (SNPs) that influence expression levels of genes associated with bipolar disorder, we jointly analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls) and a genome-wide brain (cortical) eQTL (193 healthy controls) using a Bayesian statistical method, with independent follow-up replications. The identified risk SNP was then further tested for association with hippocampal volume (n = 5775) and cognitive performance (n = 342) among healthy individuals.ResultsIntegrative analysis revealed a significant association between a brain eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes factor = 5.48; bipolar disorder P = 5.85×10(-5)). Follow-up studies across multiple independent samples confirmed the association of the risk SNP (rs6088662) with gene expression and bipolar disorder susceptibility (P = 3.54×10(-8)). Further exploratory analysis revealed that rs6088662 is also associated with hippocampal volume and cognitive performance in healthy individuals.ConclusionsOur findings suggest that 20q11.22 is likely a risk region for bipolar disorder; they also highlight the informative value of integrating functional annotation of genetic variants for gene expression in advancing our understanding of the biological basis underlying complex disorders, such as bipolar disorder.

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This study main purpose was the validation of both French and German versions of a Perceived Neighborhood Social Cohesion Questionnaire. The sample group comprised 5065 Swiss men from the "Cohort Study on Substance Use Risk Factors." Multigroup Confirmatory factor analysis showed that a three-factor model fits the data well, which substantiates the generalizability of Perceived Neighborhood Social Cohesion Questionnaire factor structure, regardless of the language. The Perceived Neighborhood Social Cohesion Questionnaire demonstrated excellent homogeneity (α = 95) and split-half reliability (r = .96). The Perceived Neighborhood Social Cohesion Questionnaire was sensitive to community size and participants' financial situation, confirming that it also measures real social conditions. Finally, weak but frequent correlations between Perceived Neighborhood Social Cohesion Questionnaire and alcohol, cigarette, and cannabis dependence were measured.

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Illicit drug analyses usually focus on the identification and quantitation of questioned material to support the judicial process. In parallel, more and more laboratories develop physical and chemical profiling methods in a forensic intelligence perspective. The analysis of large databases resulting from this approach enables not only to draw tactical and operational intelligence, but may also contribute to the strategic overview of drugs markets. In Western Switzerland, the chemical analysis of illicit drug seizures is centralised in a laboratory hosted by the University of Lausanne. For over 8 years, this laboratory has analysed 5875 cocaine and 2728 heroin specimens, coming from respectively 1138 and 614 seizures operated by police and border guards or customs. Chemical (major and minor alkaloids, purity, cutting agents, chemical class), physical (packaging and appearance) as well as circumstantial (criminal case number, mass of drug seized, date and place of seizure) information are collated in a dedicated database for each specimen. The study capitalises on this extended database and defines several indicators to characterise the structure of drugs markets, to follow-up on their evolution and to compare cocaine and heroin markets. Relational, spatial, temporal and quantitative analyses of data reveal the emergence and importance of distribution networks. They enable to evaluate the cross-jurisdictional character of drug trafficking and the observation time of drug batches, as well as the quantity of drugs entering the market every year. Results highlight the stable nature of drugs markets over the years despite the very dynamic flows of distribution and consumption. This research work illustrates how the systematic analysis of forensic data may elicit knowledge on criminal activities at a strategic level. In combination with information from other sources, such knowledge can help to devise intelligence-based preventive and repressive measures and to discuss the impact of countermeasures.

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Organizing is a general problem for global firms. Firms are seeking a balance between responsiveness at the local level and efficiency through worldwide integration. In this, supply management is the focal point where external commercial supply market relations are connected with the firm's internal functions. Here, effective supplier relationship management (SRM) is essential. Global supply integration processes create new challenges for supply management professionals and new capabilities are required. Previous research has developed several models and tools for managers to manage and categorize different supplier relationship types, but the role of the firm's internal capability of managing supplier relationships in their global integration has been a clearly neglected issue. Hence, the main objective of this dissertation is to clarify how the capability of SRM may influence the firm's global competitiveness. This objective is divided into four research questions aiming to identify the elements of SRM capability, the internal factors of integration, the effect of SRM capability on strategy and how SRM capability is linked with global integration. The dissertation has two parts. The first part presents the theoretical approaches and practical implications from previous research and draws a synthesis on them. The second part comprises four empirical research papers addressing the research questions. Both qualitative and quantitative methods are utilized in this dissertation. The main contribution of this dissertation is that it aggregates the theoretical and conceptual perspectives applied to SRM research. Furthermore, given the lack of valid scales to measure capability, this study aimed to provide a foundation for an SRM capability scale by showing that the construct of SRM capability is formed of five separate elements. Moreover, SRM capability was found to be the enabler in efforts toward value chain integration. Finally, it was found that the effect of capability on global competitiveness is twofold: it reduces conflicts between responsiveness and integration, and it creates efficiency. Thus, by identifying and developing the firm's capabilities it is possible to improve performance, and hence, global competitiveness.

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Since the classic study of Simon J. Keay published in 1984, knowledge of late Roman amphorae has progressed markedly, thanks to scholars such as Michel Bonifay and Paul Reynolds, amongst others. The area studied by Keay was Catalonia, the ancient Eastern Tarraconensis. The overview here offered for this same region reveals the central role played by African imports in late Antique times, with a minor presence of the Eastern-Mediterranean and South-Hispanic (both Baetican and Lusitanian) productions. Progress in research in the last 25 years has been centred on a series of new and well-dated contexts: the data they have yielded has clarified more precisely the chronology and the proportions of the different imports. On occasion a quantitative approach may even be applied. At the same time the relationship between town and country with respect to the late Roman amphorae is proving of interest and providing results of significance.

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This is a study of team social networks, their antecedents and outcomes. In focusing attention on the structural configuration of the team this research contributes to a new wave of thinking concerning group social capital. The research site was a random sample of Finnish work organisations. The data consisted of 499 employees in 76 teams representing 48 different organisations. A systematic literature review and quantitative methods were used in conducting the research: the former primarily to establish the current theoretical position on the relationships among the variables and the latter to test these relationships. Social network analysis was the primary method used in identifying the social-network relations among the work-team members. The first and key contribution of this study is that it relates the structuralnetwork properties of work teams to behavioural outcomes, attitudinal outcomes and, ultimately, team performance. Moreover, it shows that addressing attitudinal outcomes is also important in terms of team performance; attitudinal outcomes (team identity) mediated the relationship between the team’s performance and its social network. The second contribution is that it examines the possible antecedents of the social structure. It is thus one response to Salancik’s (1995) call for a network theory in that it explains why certain network characteristics exist. Itdemonstrates that irrespective of whether or not a team is heterogeneous in terms of age or gender, educational diversity may protect it from centralisation. However, heterogeneity in terms of gender turned out to have a negative impact on density. Thirdly, given the observation that the benefits of (team) networks are typically theorised and modelled without reference to the nature of the relationships comprising the structure, the study directly tested whether team knowledge mediated the effects of instrumental and expressive network relationships on team performance. Furthermore, with its focus on expressive networks that link the workplace to a more informal world, which have been rather neglected in previous research, it enhances knowledge of teams andnetworks. The results indicate that knowledge sharing fully mediates the influence of complementarities between dense and fragmented instrumental network relationships, thus providing empirical validation of the implicit understanding that networks transfer knowledge. Fourthly, the study findings suggest that an optimal configuration of the work-team social-network structure combines both bridging and bonding social relationships.

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A photometric procedure was developed for determination of aflatoxin B1 in peanuts by TLC-CCD technique. The quantification and detection limit were 1.2 μg kg-1 and 0.4 ng per spot, respectively, with mean recovery of 98%. The CCD camera is sufficiently sensitive to detect small changes in spots fluorescence intensity and the results for performance confirmed the efficiency of the method. Another important property of CCD detector is its linearity for a wide range of luminous stimulus determined by analysis of five-point calibration curves using the intensity of AFB1 fluorescence versus AFB1 concentration (0.8 to 4.8 ng per spot). The method was applied to the analysis of thirty nine peanut samples and aflatoxin B1 levels ranged from 16 to 115 μg kg-1. The TLC-CCD and the photometric procedure developed in this study demonstrated to be a simple and efficient tool for quantitative analyses of AFB1 in peanut samples.

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The atomic shell structure can be observed by inspecting the experimental periodic properties of the Periodic Table. The (quantum) shell structure emerges from these properties and in this way quantum mechanics can be explicitly shown considering the (semi-)quantitative periodic properties. These periodic properties can be obtained with a simple effective Bohr model. An effective Bohr model with an effective quantum defect (u) was considered as a probe in order to show the quantum structure embedded in the Periodic Table. u(Z) shows a quasi-smoothed dependence of Z, i.e., u(Z) ≈ Z2/5 - 1.

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Leadership is essential for the effectiveness of the teams and organizations they are part of. The challenges facing organizations today require an exhaustive review of the strategic role of leadership. In this context, it is necessary to explore new types of leadership capable of providing an effective response to new needs. The presentday situations, characterized by complexity and ambiguity, make it difficult for an external leader to perform all leadership functions successfully. Likewise, knowledge-based work requires providing professional groups with sufficient autonomy to perform leadership functions. This study focuses on shared leadership in the team context. Shared leadership is seen as an emergent team property resulting from the distribution of leadership influence across multiple team members. Shared leadership entails sharing power and influence broadly among the team members rather than centralizing it in the hands of a single individual who acts in the clear role of a leader. By identifying the team itself as a key source of influence, this study points to the relational nature of leadership as a social construct where leadership is seen as social process of relating processes that are co-constructed by several team members. Based on recent theoretical developments concerned with relational, practice-based and constructionist approaches to the study of leadership processes, this thesis proposes the study of leadership interactions, working processes and practices to focus on the construction of direction, alignment and commitment. During the research process, critical events, activities, working processes and practices of a case team have been examined and analyzed with the grounded theory –approach in the terms of shared leadership. There are a variety of components to this complex process and a multitude of factors that may influence the development of shared leadership. The study suggests that the development process of shared leadership is a common sense -making process and consists of four overlapping dimensions (individual, social, structural, and developmental) to work with as a team. For shared leadership to emerge, the members of the team must offer leadership services, and the team as a whole must be willing to rely on leadership by multiple team members. For these individual and collective behaviors to occur, the team members must believe that offering influence to and accepting it from fellow team members are welcome and constructive actions. Leadership emerges when people with differing world views use dialogue and collaborative learning to create spaces where a shared common purpose can be achieved while a diversity of perspectives is preserved and valued. This study also suggests that this process can be supported by different kinds of meaning-making and process tools. Leadership, then, does not reside in a person or in a role, but in the social system. The built framework integrates the different dimensions of shared leadership and describes their relationships. This way, the findings of this study can be seen as a contribution to the understanding of what constitutes essential aspects of shared leadership in the team context that can be of theoretical value in terms of advancing the adoption and development process of shared leadership. In the real world, teams and organizations can create conditions to foster and facilitate the process. We should encourage leaders and team members to approach leadership as a collective effort that the team can be prepared for, so that the response is rapid and efficient.

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The loss of large areas of Cerrado (Brazilian savanna) in Brazil can lead to reduced biodiversity and to the extinction of species. Therefore, the present study aimed to investigate the genetic fragility of populations of Copaifera langsdorffii Desf exposed to different anthropic conditions in fragments of Cerrado in the state of São Paulo. The study was carried out in two Experimental Stations operated by the Forest Institute (Assis and Itirapina), in one fully protected conservation unit (Pedregulho) and in one private property (Brotas). Analyses were conducted using leaf samples from 353 adult specimens and eight pairs of microsatellite loci. The number of alleles per locus ranged from 13 to 15 in all populations, but the mean number of effective alleles was approximately half this value (7.2 to 9-1). Observed heterozygosity was significant and lower than the expected in all populations. Consequently, all populations deviated from Hardy-Weinberg expected frequencies. Fixation indexes were significant for all populations, with the Pedregulho population having the lowest value (0.189) and Itirapina having the highest (0.283). The analysis of spatial genetic structure detected family structures at distance classes of 20 to 65 m in the populations studied. No clones were detected in the populations. Estimates of effective population size were low, but the area occupied by each population studied was large enough for conservation, medium and long term. Recent reductions or bottlenecks were detected in all four populations. Mean Gst’ (genetic divergence) indicated that most of the variation was within populations. Cluster structure analysis based on the genotypes detected K= 4 clusters with distinct allele frequencies patterns. The genetic differentiation observed among populations is consistent with the hypothesis of genetic and geographic isolation. Therefore, it is essential to adopt conservation strategies that raise the gene flow between fragments.

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This study aimed to describe the probabilistic structure of the annual series of extreme daily rainfall (Preabs), available from the weather station of Ubatuba, State of São Paulo, Brazil (1935-2009), by using the general distribution of extreme value (GEV). The autocorrelation function, the Mann-Kendall test, and the wavelet analysis were used in order to evaluate the presence of serial correlations, trends, and periodical components. Considering the results obtained using these three statistical methods, it was possible to assume the hypothesis that this temporal series is free from persistence, trends, and periodicals components. Based on quantitative and qualitative adhesion tests, it was found that the GEV may be used in order to quantify the probabilities of the Preabs data. The best results of GEV were obtained when the parameters of this function were estimated using the method of maximum likelihood. The method of L-moments has also shown satisfactory results.

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Tämän tutkimuksen tarkoituksena oli tutkia Päijät-Hämeen sosiaali- ja terveydenhuollon kuntayhtymän Tukipalvelukeskuksen teknisten palveluiden tulosalueen tuotteistamista ja tuottaa kustannusten laskutuksen periaatteellinen toteutusmalli. Työssä otetaan kantaa palveluiden hinnoittelumalleihin eli kuinka kiinteistöistä ja teknisistä ylläpitopalveluista syntyvät kustannukset voidaan osoittaa niitä käyttäville tulosalueille. Palveluiden jäsentäminen ja suoritteiden yhdistäminen muodostavat palvelutuotteen, jota palveluita käyttävälle asiakkaalle tarjotaan. Tuotekäsitteelle on tyypillistä, että sitä voidaan tuottaa saman sisältöisenä nyt ja tulevaisuudessa. Tuotteita tarjoavan palveluiden tuottajan tuotekriteerit sisältävät selkeät tuoteryhmät, tuotteiden määrällisen mitattavuuden, kuvaavat tuotenimikkeet ja tuotteilla on ostajan näkökulmasta selkeä sisältö ja hinnoittelu. Tuotteistamisen tärkein hyöty on organisaation kustannusrakenteen selkeytyminen, jonka vuoksi tuotteiden määrä, laatu ja hinta tulee olla määriteltävissä. Asiakkaalle voidaan tarjota valmiiksi hinnoiteltuja palveluosia, jolloin palveluiden räätälöinti ja modulointi ovat mahdollisia palveluiden niputtamisella. Ei-kaupallisten instanssien, kuten kuntayhtymien sisäinen laskutus ja tuotteistus mahdollistavat palveluiden standardoimisen ja johdon päätöksenteko toimialakohtaisen kustannustietoisuuden vuoksi paranee. Tutkimuksen alkuosassa paneudutaan palvelun alle kuuluviin käsitteisiin, kuten tuotteistamisajatteluun, palvelupaketteihin, palveluiden laadun mittaamiseen ja palveluiden hinnoitteluun. Lisäksi tutkimuksessa käsitellään teknisten palveluiden hinnoitteluun käytettävän toimintoperusteisen kustannuslaskennan sekä sisäisen vuokraamisen periaatteita. Teoreettisessa viitekehyksessä käsiteltyjä asioita käytettiin hyödyksi sairaanhoitopiireille laadittuun kyselytutkimukseen. Yhdessä teorian ja kyselytutkimuksen kanssa kohdeorganisaatiolle luotiin malli palveluiden tuotteistamiseksi.

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The purpose of this study is to examine and explain firm`s growth impact on capital structure decision-making in research and development intensive companies. Many studies claim that R&D has a pivotal impact on capital structure decisions, but corporate finance theories have often failed to explain these observed patterns. As sales growth is an important concept and objective for R&D firms, it is logical to assume that it plays a vital role in capital structure decisions. This study applies nomothetic research approach. The theoretical part employs a formal conceptual analysis in order to develop the propositions that are tested with empirical data. The empirical part consists of the analysis of three companies; the data is obtained from the annual reports over the period 2003 – 2008. The companies operate in IT- or ICT-industry and are publicly listed. The method for analyzing the case data is based on the financial indicators, which are obtained from the financials of the case companies. These economic indicators describe the capital structure and the financial decision-making of the firms. The method relates to the quantitative studies. Yet, this study extends the analysis beyond the indicators. Specifically, this study addresses the question of what is behind the economic indicators, therefore combining aspects of quantitative and qualitative analysis. The firms examined in this study seem to prefer internal finance during growth. However, external finance seems to be a catalyst for sales growth. Firms strongly prefer equity financing. In growth, the use of equity per capital either increases or stays in a constant level. Over the period 2003 – 2008, the firms were often associated to equity related transactions and short-term debt. Short-term debt was used as a substitute of long-term debt and equity. The case firms also adjusted their capital structure – these adjustments were carried out with short-term debt or equity. The case data also provides implications for the growth signal theory that was developed in this study. Based on the econometric indicators, arguments can be made that equity investors are `attracted` to growing R&D firms. This is because growth helps investors perceive the true type of firm. The findings of this study are best explained by the trade-off theory and the pecking order theory. These corporate finance theories are considered as mainstream. Little support can be found to the implications of the signaling theory and market timing theory.