962 resultados para Back analysis


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2 Centre of Research, Education, Innovation and Intervention In Sport, Faculty of Sport, University of Porto, Portugal Background: Regarding children aged _10 years, only a few international studies were conducted to determine the prevalence of and risk factors for back pain. Although other studies on the older Portuguese children point to prevalence between 17% and 39%, none exists for this specific age-group. Thus, the aim of this study was conducted to establish the prevalence of and risk factors for back pain in schoolchildren aged 7–10 years. Methods: A cross-sectional survey among 637 children was conducted. A self-rating questionnaire was used to verify prevalence and duration of back pain, life habits, school absence, medical treatments or limitation of activities. For posture assessment, photographic records with a bio-photogrammetric analysis were used to obtain data about head, acromion and pelvic alignment, horizontal alignment of the scapulae, vertical alignment of the trunk and vertical body alignment. Results: Postural problems were found in 25.4% of the children, especially in the 8- and 9-year-old groups. Back pain occurs in 12.7% with the highest values among the 7- and 10-year-old children. The probability of back pain increased 7 times when the children presented a history of school absences, 4.3 times when they experienced sleeping difficulties, 4.4 times when school furniture was uncomfortable, 4.7 times if the children perceived an occurrence of parental back pain and 2.5 times when children presented incorrect posture. Conclusions: The combination of school absences, parental pain, sleeping difficulties, inappropriate school furniture and postural deviations at the sagittal and frontal planes seem to prove the multifactorial aetiology of back pain.

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RESUMO: Um dos principais resultados das intervenções de Fisioterapia dirigidas a utentes com Dor Lombar Crónica (DLC) é reduzir a incapacidade funcional. A Quebec Back Pain Disability Scale (QBPDS) é um instrumento amplamente aceite a nível internacional na medição do nível de incapacidade funcional reportada pelos indivíduos com DLC. O objetivo deste estudo é dar um contributo para a adaptação cultural da versão portuguesa da QBPDS (QBPDS-VP) e investigar o poder de resposta e interpretabilidade da escala. Metodologia: Realizou-se um estudo metodológico, multicentro, baseado num coorte prospetivo de 132 utentes com DLC. Os utentes foram recrutados a partir da lista de espera de 16 serviços de Medicina Física e de Reabilitação/Fisioterapia de várias áreas geográficas de Portugal. A QBPDS- VP foi administrada 3 vezes, em 3 momentos de recolha de dados distintos: T0 - momento inicial (utentes em lista de espera); T1 - 1 semana de intervalo (início dos tratamentos de Fisioterapia); e T2 - 6 semanas de intervalo (pós-intervenção de Fisioterapia). Os dados recolhidos em T0 foram utilizados para a análise fatorial e para o estudo da consistência interna (n=132); os dados da amostra emparelhada de T0 e T1 (n=132) para a fiabilidade teste-reteste; e os dados da amostra emparelhada de T0 e T2 (n=120) para a análise do poder de resposta e interpretabilidade. A âncora externa utilizada foi a perceção global de mudança, neste caso a PGIC- VP, que foi respondida em T1 e T2. O nível de significância para o qual os valores se consideraram satisfatórios foi de p≤ 0,05. O tratamento dos dados foi realizado no software IBM SPSS Statistics (versão 20). Resultados: A QBPDS- VP é uma escala unidimensional, que revela uma excelente consistência interna (α de Cronbach= 0,95) e uma fiabilidade teste-reteste satisfatória (CCI= 0,696; IC 95%: 0,581–0,783). Esta escala demonstrou um poder de resposta moderado, quando aplicada em utentes com DLC ( = 0,426 e AAC= 0,741; IC 95%: 0,645 – 0,837). A Diferença Mínima Detetável (DMD) estimada foi de 19 pontos e as estimativas da Diferença Mínima Clinicamente Importante (DMCI) variaram entre 7 (pelo método curva ROC) e 8 pontos (pelo método “diferença média de pontuação”). A estimativa pela curva ROC deriva do ponto ótimo de corte de 6,5 pontos, com Área Abaixo da Curva (AAC)= 0,741, sensibilidade de 72%, e especificidade de 71%. Uma análise complementar da curva ROC baseada nas diferenças de pontuações da QBPDS, expressa em percentagem, revelou um ponto ótimo de corte de - 24% (AAC= 0,737, sensibilidade de 71%, e especificidade de 71%). Para pontuações iniciais da QBPDS- VP mais altas (≥34 pontos), foi encontrado um ponto ótimo de corte de 10,5 pontos (AAC= 0,738, sensibilidade de 73%, e especificidade de 67%). Conclusão: A QBPDS-VP demonstrou bons níveis de fiabilidade e poder de resposta, recomendando-se o seu uso na medição e avaliação da incapacidade funcional de utentes com DLC. A DMD estimada, de 19 pontos, determinou uma amplitude válida da QBPDS-VP de 19 a 81 pontos. Este estudo propõe estimativas de DMCI da QBPDS- VP numa aplicação específica da escala (em utentes com DLC que são referidos para a intervenção de Fisioterapia). A pontuação inicial da QBPDS- VP deve ser considerada na interpretação de mudanças de pontuação, após a intervenção de Fisioterapia.------------ ABSTRACT: One of the main results of physiotherapy interventions for patients with Chronic Low Back Pain (CLBP) is decrease the functional disability. The Quebec Back Pain Disability Scale (QBPDS) is an instrument widely accepted internationally, in measuring the level of disability reported by individuals with CLBP. The purpose of this study is to contribute to the cultural adaptation of the Portuguese version of QBPDS (QBPDS - PV) and investigate the Responsiveness and Interpretability of QBPDS-PV. Methodology: This was a methodological and multicenter study, based on a sample of 132 subjects with CLBP. The patients were recruited from the waiting lists of 16 medicine rehabilitation service, in many Portugal districts. The Quebec Back Pain Disability Scale was administered in three different moments: T0 – baseline (patients in the waiting list); T1- one week after T0 (the beginning of treatment); and T2 – six weeks after T1 (the posttreatment). The data collected at T0 were used for factor analysis and to study the internal consistency (n = 132); paired sample data of T0 and T1 (n=132) were used for test-retest reliability, and sample data paired for T0 and T2 (n=120) used for responsiveness and interpretability analysis. The external anchor was the global perception of change, measured by the Portuguese version of Patient’s Global Impression of Change (PGIC) Scale. The minimal level of significance established was p ≤ 0,05. Data analysis was performed using the IBM SPSS Statistics software (version 20). Results: The QBPDS-PV is a unidimensional scale, demonstrates an excellent internal consistency (Cronbach's α=0.95) and satisfactory test-retest reliability (ICC= 0.696, 95% CI: 0.581–0.783). The scale revealed moderate responsiveness when applied to patients with CLBP ( = 0.426 and AUC= 0.741, 95% CI: 0.645 - 0.837). The Smallest Detectable Change (SDC) was 19 points, whereas the Minimal Clinically Important Change (MCIC) ranged between 7 (ROC curve method) and 8 points (by the "mean difference score"). The estimate was derived from the ROC curve by an optimal cutoff point of 6.5 points, with Area Under the Curve (AUC)= 0.741, sensitivity 72%, and specificity of 71%. A complementary analysis of the ROC curve based on differences in QBPDS scores from baseline, expressed in percentage, revealed an optimal cutoff point of -24% (AUC= 0.737, sensitivity of 71%, and specificity of 71%). For the highest initial scores of QBPDS-PV (≥ 34 points) was found an optimal cutoff of 10.5 points (AUC= 0.738, sensitivity of 73%, and specificity 67%). Conclusion: The QBPDS-PV demonstrated good levels of reliability and responsiveness, being recommended its use in the measurement and evaluation of disability of patients with CLBP. The SDC of 19 points determined the QBPDS‟ scale width of 19 to 81. This study proposes MCIC values for QBPDS –PV for this specific setting (in CLBP patients who are referred for physiotherapy intervention). The QBPDS –PV baseline score have to be taken into account while interpreting the score change after physiotherapy intervention.

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The action of fenthion was studied in a 15% epicutaneous formulation upon Rhipicephalus sanguineus, which may transmit pathogens to men and other animals, such as Ehrlichia, Babesia and Ricketsia. Dogs were artificially infected for the trial. The fenthion bioassays were begun four months after artificial infestation. The test group, having a mean of 186 ticks per dog, received the formulation dosage according to body weight on the neck region. Tick counts were performed, considering diameters > or = 2mm, during 11 days of treatment, in the most affected body areas: back, ears and paws. Before the application of fenthion in the dogs, it were observed an average 43.3% ticks in the ears, 38.1% in the back area and 17.6% in the paws. The number of ticks in dogs decreased by 36.2%, 63.8%, 82.7%, 67%, 40% and 4.9%, respectively on days 1, 2, 3, 5, 7, 9 and 11 after treatment. R. sanguineus anti-tick activity, lower than that officially recommended, was verified. The number of ticks increased progressively after the 5th day, demonstrating residual insecticide inefficacy. The results obtained did not indicate the use of this formulation, at the tested dosage, as an elective measure for R. sanguineus control.

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A Zero waste management is believed to be one of methods to gain sustainability in urban areas. Take advantages of resources as enough as the needs and process it until the last part to be wasted is a contribution to take care the environment for the next generation. Reduce, reuse, and recycle are three simplesactivities which are until nowadays consideredas the back bone of zero waste. Jonggolgreen city is a new urban area in Indonesia with a 100 ha of surface area zoned as education tourism area. It is an independent area with pure natural resources of water, air, and land to be managed and protected. It is planned as green city through zero waste management since2013. In this preliminary period, a monitoring tool is being prepared by applying a Life Cycle Analysis (LCA) for urban areas [1]. This paper will present an explanatory assessment ofthe zero waste management for Jonggolgreen city. The existing situation will be examined through LCA and afterwards,the new program and the proposed green design to gain the next level of zero waste will be discussed. The purpose is to track the persistence of the commitment and the perception of the necessary innovationsin order to achieve the ideal behavior level of LCA.

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The purpose of this paper is to highlight the curiously circular course followed by mainstream macroeconomic thinking in recent times. Having broken from classical orthodoxy in the late 1930s via Keynes’s General Theory, over the last three or four decades the mainstream conventional wisdom, regressing rather than progressing, has now come to embrace a conception of the working of the macroeconomy which is again of a classical, essentially pre-Keynesian, character. At the core of the analysis presented in the typical contemporary macro textbook is the (neo)classical model of the labour market, which represents employment as determined (given conditions of productivity) by the terms of labour supply. While it is allowed that changes in aggregate demand may temporarily affect output and employment, the contention is that in due course employment will automatically return to its ‘natural’ (full employment) level. Unemployment is therefore identified as a merely frictional or voluntary phenomenon: involuntary unemployment - in other words persisting demand-deficient unemployment - is entirely absent from the picture. Variations in aggregate demand are understood to have a lasting impact only on the price level, not on output and employment. This in effect amounts to a return to a Pigouvian conception such as targeted by Keynes in the General Theory. We take the view that this reversion to ideas which should by now be obsolete reflects not the discovery of logical or empirical deficiencies in the Keynes analysis, but results rather from doctrinaire blindness and failure of scholarship on account of which essential features of the Keynes theory have been overlooked or misrepresented. There is an urgent need for a critical appraisal of the current conventional macroeconomic wisdom.

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Genuine Savings has emerged as a widely-used indicator of sustainable development. In this paper, we use long-term data stretching back to 1870 to undertake empirical tests of the relationship between Genuine Savings (GS) and future well-being for three countries: Britain, the USA and Germany. Our tests are based on an underlying theoretical relationship between GS and changes in the present value of future consumption. Based on both single country and panel results, we find evidence supporting the existence of a cointegrating (long run equilibrium) relationship between GS and future well-being, and fail to reject the basic theoretical result on the relationship between these two macroeconomic variables. This provides some support for the GS measure of weak sustainability. We also show the effects of modelling shocks, such as World War Two and the Great Depression.

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ABSTRACT Objectives: Patients with failed back surgery syndrome (FBSS) and chronic neuropathic pain experience levels of health-related quality of life (HRQoL) that are considerably lower than those reported in other areas of chronic pain. The aim of this article was to quantify the extent to which reductions in (leg and back) pain and disability over time translate into improvements in generic HRQoL as measured by the EuroQoL-5D and SF-36 instruments. Methods: Using data from the multinational Prospective, Randomized, Controlled, Multicenter Study of Patients with Failed Back Surgery Syndrome trial, we explore the relationship between generic HRQoL-assessed using two instruments often used in clinical trials (i.e., the SF-36 and EuroQol-5D)-and disease-specific outcome measures (i.e., Oswestry disability index [ODI], leg and back pain visual analog scale [VAS]) in neuropathic patients with FBSS. Results: In our sample of 100 FBSS patients, generic HRQoL was moderately associated with ODI (correlation coefficient: -0.462 to -0.638) and mildly associated with leg pain VAS (correlation coefficient: -0.165 to -0.436). The multilevel regression analysis results indicate that functional ability (as measured by the ODI) is significantly associated with HRQoL, regardless of the generic HRQoL instrument used. On the other hand, changes over time in leg pain were significantly associated with changes in the EuroQoL-5D and physical component summary scores, but not with the mental component summary score. Conclusions: Reduction in leg pain and functional disability is statistically significantly associated with improvements in generic HRQoL. This is the first study to investigate the longitudinal relationship between generic and disease-specific HRQoL of neuropathic pain patients with FBSS, using multinational data.

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BACKGROUND: Adequate pain assessment is critical for evaluating the efficacy of analgesic treatment in clinical practice and during the development of new therapies. Yet the currently used scores of global pain intensity fail to reflect the diversity of pain manifestations and the complexity of underlying biological mechanisms. We have developed a tool for a standardized assessment of pain-related symptoms and signs that differentiates pain phenotypes independent of etiology. METHODS AND FINDINGS: Using a structured interview (16 questions) and a standardized bedside examination (23 tests), we prospectively assessed symptoms and signs in 130 patients with peripheral neuropathic pain caused by diabetic polyneuropathy, postherpetic neuralgia, or radicular low back pain (LBP), and in 57 patients with non-neuropathic (axial) LBP. A hierarchical cluster analysis revealed distinct association patterns of symptoms and signs (pain subtypes) that characterized six subgroups of patients with neuropathic pain and two subgroups of patients with non-neuropathic pain. Using a classification tree analysis, we identified the most discriminatory assessment items for the identification of pain subtypes. We combined these six interview questions and ten physical tests in a pain assessment tool that we named Standardized Evaluation of Pain (StEP). We validated StEP for the distinction between radicular and axial LBP in an independent group of 137 patients. StEP identified patients with radicular pain with high sensitivity (92%; 95% confidence interval [CI] 83%-97%) and specificity (97%; 95% CI 89%-100%). The diagnostic accuracy of StEP exceeded that of a dedicated screening tool for neuropathic pain and spinal magnetic resonance imaging. In addition, we were able to reproduce subtypes of radicular and axial LBP, underscoring the utility of StEP for discerning distinct constellations of symptoms and signs. CONCLUSIONS: We present a novel method of identifying pain subtypes that we believe reflect underlying pain mechanisms. We demonstrate that this new approach to pain assessment helps separate radicular from axial back pain. Beyond diagnostic utility, a standardized differentiation of pain subtypes that is independent of disease etiology may offer a unique opportunity to improve targeted analgesic treatment.

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Factor analysis as frequent technique for multivariate data inspection is widely used also for compositional data analysis. The usual way is to use a centered logratio (clr)transformation to obtain the random vector y of dimension D. The factor model istheny = Λf + e (1)with the factors f of dimension k & D, the error term e, and the loadings matrix Λ.Using the usual model assumptions (see, e.g., Basilevsky, 1994), the factor analysismodel (1) can be written asCov(y) = ΛΛT + ψ (2)where ψ = Cov(e) has a diagonal form. The diagonal elements of ψ as well as theloadings matrix Λ are estimated from an estimation of Cov(y).Given observed clr transformed data Y as realizations of the random vectory. Outliers or deviations from the idealized model assumptions of factor analysiscan severely effect the parameter estimation. As a way out, robust estimation ofthe covariance matrix of Y will lead to robust estimates of Λ and ψ in (2), seePison et al. (2003). Well known robust covariance estimators with good statisticalproperties, like the MCD or the S-estimators (see, e.g. Maronna et al., 2006), relyon a full-rank data matrix Y which is not the case for clr transformed data (see,e.g., Aitchison, 1986).The isometric logratio (ilr) transformation (Egozcue et al., 2003) solves thissingularity problem. The data matrix Y is transformed to a matrix Z by usingan orthonormal basis of lower dimension. Using the ilr transformed data, a robustcovariance matrix C(Z) can be estimated. The result can be back-transformed tothe clr space byC(Y ) = V C(Z)V Twhere the matrix V with orthonormal columns comes from the relation betweenthe clr and the ilr transformation. Now the parameters in the model (2) can beestimated (Basilevsky, 1994) and the results have a direct interpretation since thelinks to the original variables are still preserved.The above procedure will be applied to data from geochemistry. Our specialinterest is on comparing the results with those of Reimann et al. (2002) for the Kolaproject data

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Purpose: To evaluate the diagnostic value and image quality of CT with filtered back projection (FBP) compared with adaptive statistical iterative reconstructed images (ASIR) in body stuffers with ingested cocaine-filled packets.Methods and Materials: Twenty-nine body stuffers (mean age 31.9 years, 3 women) suspected for ingestion of cocaine-filled packets underwent routine-dose 64-row multidetector CT with FBP (120kV, pitch 1.375, 100-300 mA and automatic tube current modulation (auto mA), rotation time 0.7sec, collimation 2.5mm), secondarily reconstructed with 30 % and 60 % ASIR. In 13 (44.83%) out of the body stuffers cocaine-filled packets were detected, confirmed by exact analysis of the faecal content including verification of the number (range 1-25). Three radiologists independently and blindly evaluated anonymous CT examinations (29 FBP-CT and 68 ASIR-CT) for the presence and number of cocaine-filled packets indicating observers' confidence, and graded them for diagnostic quality, image noise, and sharpness. Sensitivity, specificity, area under the receiver operating curve (ROC) Az and interobserver agreement between the 3 radiologists for FBP-CT and ASIR-CT were calculated.Results: The increase of the percentage of ASIR significantly diminished the objective image noise (p<0.001). Overall sensitivity and specificity for the detection of the cocaine-filled packets were 87.72% and 76.15%, respectively. The difference of ROC area Az between the different reconstruction techniques was significant (p= 0.0101), that is 0.938 for FBP-CT, 0.916 for 30 % ASIR-CT, and 0.894 for 60 % ASIR-CT.Conclusion: Despite the evident image noise reduction obtained by ASIR, the diagnostic value for detecting cocaine-filled packets decreases, depending on the applied ASIR percentage.

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Purpose: Collaboration and interprofessional practices are highly valued in health systems everywhere, partly based on the rationale that they improve outcomes of care for people with complex health problems, such as low back pain. Research in the area of low back pain also supports the involvement of different health professionals in the interventions for people who present this condition. The aim of this studywas to identify factors influencing the interprofessional practices of physiotherapists working in private settings with people with low back pain. Relevance: Physiotherapists, like other health professionals, are encouraged to engage in interprofessional practices in their dailywork. However, to date, very little is known of their interprofessional practices, especially in private settings. Understanding physiotherapists' interprofessional practices and their influencing factors will notably advance knowledge relating to the organisation of physiotherapy services for people with low back pain. Participants: Participants in this study were 13 physiotherapists including 10 women and 3 men, having between 3 and 22 years of professional experience, and working in one of 10 regions of the Province of Quebec (Canada). In order to obtain maximal variation in the perspectives, participants were selected using a recruitment matrix including three criteria: duration of professional experience, work location, and physical proximity with other professionals. Methods: Thiswas a descriptive qualitative study using faceto- face semi-structured interviews as the main method of data collection. An interview guide was developed based on an evidence-derived frame of reference. Each interview lasted between 55 and 95 minutes and was transcribed verbatim. Analysis: Qualitative analyses took the form of content analysis, encompassing data coding and general thematic regrouping. NVivo version 8 was used to assist data organisation and analysis. Results: Multiple factors influencing the interprofessional practices of physiotherapists were identified. The main factors include the consulting person's health condition, the extent of knowledge on health professionals' roles and fields of practice, the proximity and availability of professional resources, as well as daily work schedules. Conclusions: Our findings highlight the influence of multiple factors on physiotherapists' interprofessional practices, including professional practice and organisational issues. However, further research on the interprofessional practices of physiotherapists is still required. Research priorities targeting the views of other health professionals, as well as those of services users, would enhance our comprehension of interprofessional practices of physiotherapists. Implications: This study provides new insights that improve our understanding of the interprofessional practices of physiotherapists working in private settings with people with low back pain, more specifically on the factors influencing these practices. Based on our findings, implementing changes such as improving current and future health professionals' knowledge of the fields and roles of other health professionals through training may contribute to positively influencing interprofessional practices. Keywords: Interprofessional practices; Private practice; Low back pain Funding acknowledgements: This research was supported in part by a B.E. Schnurr Memorial Fund Research Grant administered by the Physiotherapy Foundation of Canada, as well as from a clinical research partnership in physiotherapy between the Quebec Rehabilitation Research Network (REPAR) and the Ordre professionnel de la physiothérapie du Québec (OPPQ). KP received doctoral-level scholarships from the Canadian Institutes of Health Research (CIHR) and the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). CE Dionne is a FRSQ senior Research Scholar. Ethics approval: This project was approved by the ethics research committee of the Institut de réadaptation en déficience physique de Québec.

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First: A continuous-time version of Kyle's model (Kyle 1985), known as the Back's model (Back 1992), of asset pricing with asymmetric information, is studied. A larger class of price processes and of noise traders' processes are studied. The price process, as in Kyle's model, is allowed to depend on the path of the market order. The process of the noise traders' is an inhomogeneous Lévy process. Solutions are found by the Hamilton-Jacobi-Bellman equations. With the insider being risk-neutral, the price pressure is constant, and there is no equilibirium in the presence of jumps. If the insider is risk-averse, there is no equilibirium in the presence of either jumps or drifts. Also, it is analised when the release time is unknown. A general relation is established between the problem of finding an equilibrium and of enlargement of filtrations. Random announcement time is random is also considered. In such a case the market is not fully efficient and there exists equilibrium if the sensitivity of prices with respect to the global demand is time decreasing according with the distribution of the random time. Second: Power variations. it is considered, the asymptotic behavior of the power variation of processes of the form _integral_0^t u(s-)dS(s), where S_ is an alpha-stable process with index of stability 0&alpha&2 and the integral is an Itô integral. Stable convergence of corresponding fluctuations is established. These results provide statistical tools to infer the process u from discrete observations. Third: A bond market is studied where short rates r(t) evolve as an integral of g(t-s)sigma(s) with respect to W(ds), where g and sigma are deterministic and W is the stochastic Wiener measure. Processes of this type are particular cases of ambit processes. These processes are in general not of the semimartingale kind.

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ABSTRACTIn contrast to animals, plants cannot move from their place of birth and, therefore, need to adapt to their particular habitat in order to survive. Thus, plant development is remarkably plastic, making plants an ideal system for the isolation of genes that account for intraspecific natural variation and possibly environmental adaptation. However, to date, this approach mostly identified null alleles and missed mutations with subtle effects. For instance, BREVIS RADIX (BRX) has been isolated as a key regulator of root growth through a naturally occurring loss-of-function allele in the Arabidopsis thaliana accession Uk-1 and is the founding member of a highly-conserved plant-specific gene family.In this work, we show that a strong selective pressure is acting on the BRX gene family and dates back before the monocot-dicot divergence. However, functional diversification is observed mainly in dicotyledon BRX family genes and is correlated with acceleration in the evolutionary rates in the N-terminal regions. Population genetic data revealed that BRX is highly conserved across Arabidopsis accessions and presents signatures of adaptation. Interestingly, a seven amino acid deletion polymorphism in BRX sequence was found in a few accessions, which seems to be responsible for their enhanced primary root growth. Nevertheless, BRX might not only be active in the root, as suggested by its expression in the shoot. Indeed, leaves and cotyledons of brx mutants are significantly smaller than wild- type. This phenotype is a direct consequence of the absence of BRX function in the shoot rather than an indirect effect of an altered root system growth. Interestingly, cotyledons of brx plants reflect the same physiological defects as the root. Moreover, phenotypes in BRX gain-of-function plants, such as epinastic leaves and increased epidermal cell size, could be associated with an increase in leaf brassinosteroid content.Collectively, these results indicate that BRX contributes to local adaptation by ubiquitously regulating plant growth, probably through the modulation of brassinosteroid biosynthesis.RÉSUMÉContrairement à la plupart des animaux, les plantes ne peuvent se mouvoir et doivent ainsi s'adapter à leur environnement pour survivre. Pour cette raison, elles représentent un système idéal pour l'identification de gènes contribuant à la variation naturelle intra- spécifique, ainsi qu'à l'adaptation. Cependant, cette approche a, jusqu'à présent, surtout permis d'isoler des allèles nuls et non des mutations conférant des effets plus subtiles. C'est le cas du gène Β REVIS RADIX (BRX), un régulateur clé de la croissance racinaire, qui a été identifié grâce à un allèle non-fonctionnel présent dans l'accession naturelle d'Arabidopsis thaliana Uk-1. BRX et ses homologues des plantes mono- et dicotylédones forment une famille très conservée et spécifique aux plantes.Dans ce travail, nous démontrons que la famille de gènes BRX est soumise à une forte pression de sélection qui remonte avant la divergence entre mono- et dicotylédones. Cependant, une diversification fonctionnelle a été observée chez les gènes des dicotylédones et corrèle avec une accélération de la vitesse d'évolution dans leur région N- terminale. Une analyse génétique de différentes accessions naturelles d'Arabidopsis a révélé que BRX est hautement conservé et présente des signatures d'adaptation. Remarquablement, un polymorphisme de délétion de sept acides aminés a été détecté dans quelques accessions et a pour conséquence une plus forte croissance de la racine primaire. Néanmoins, il semble que le rôle de BRX ne se limite pas qu'à la racine, comme indiqué par son expression dans les parties aériennes de la plante. En effet, les mutants brx présentent des cotylédons et des feuilles significativement plus petits que le type sauvage, une conséquence directe de l'absence d'activité de BRX dans ces organes. Nous avons aussi noté que les cotylédons des mutants brx, à l'instar des racines, ont une perception altérée de l'auxine et peuvent être complémentés par l'application exogène de brassinostéroïdes. De plus, dans des plantes présentant un gain de fonction BRX, les feuilles sont épinastiques et les cellules de leur épiderme plus grandes. Ces phénotypes sont accompagnés d'une augmentation de la concentration de brassinostéroïdes dans les feuilles. Conjointement, ces résultats démontrent que BRX contribue à une adaptation locale de la plante par la régulation générale de sa croissance, probablement en modulant la biosynthèse des brassinostéroïdes.

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BACKGROUND Low back pain and its associated incapacitating effects constitute an important healthcare and socioeconomic problem, as well as being one of the main causes of disability among adults of working age. The prevalence of non-specific low back pain is very high among the general population, and 60-70% of adults are believed to have suffered this problem at some time. Nevertheless, few randomised clinical trials have been made of the efficacy and efficiency of acupuncture with respect to acute low back pain. The present study is intended to assess the efficacy of acupuncture for acute low back pain in terms of the improvement reported on the Roland Morris Questionnaire (RMQ) on low back pain incapacity, to estimate the specific and non-specific effects produced by the technique, and to carry out a cost-effectiveness analysis. METHODS/DESIGN Randomised four-branch controlled multicentre prospective study made to compare semi-standardised real acupuncture, sham acupuncture (acupuncture at non-specific points), placebo acupuncture and conventional treatment. The patients are blinded to the real, sham and placebo acupuncture treatments. Patients in the sample present symptoms of non specific acute low back pain, with a case history of 2 weeks or less, and will be selected from working-age patients, whether in paid employment or not, referred by General Practitioners from Primary Healthcare Clinics to the four clinics participating in this study. In order to assess the primary and secondary result measures, the patients will be requested to fill in a questionnaire before the randomisation and again at 3, 12 and 48 weeks after starting the treatment. The primary result measure will be the clinical relevant improvement (CRI) at 3 weeks after randomisation. We define CRI as a reduction of 35% or more in the RMQ results. DISCUSSION This study is intended to obtain further evidence on the effectiveness of acupuncture on acute low back pain and to isolate the specific and non-specific effects of the treatment.

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Pounamu (NZ jade), or nephrite, is a protected mineral in its natural form following thetransfer of ownership back to Ngai Tahu under the Ngai Tahu (Pounamu Vesting) Act 1997.Any theft of nephrite is prosecutable under the Crimes Act 1961. Scientific evidence isessential in cases where origin is disputed. A robust method for discrimination of thismaterial through the use of elemental analysis and compositional data analysis is required.Initial studies have characterised the variability within a given nephrite source. This hasincluded investigation of both in situ outcrops and alluvial material. Methods for thediscrimination of two geographically close nephrite sources are being developed.Key Words: forensic, jade, nephrite, laser ablation, inductively coupled plasma massspectrometry, multivariate analysis, elemental analysis, compositional data analysis