Mécanismes neuronaux médullaires, coordination musculaire et fonction motrice chez les sujets hémiparétiques

Dans l’hémiparésie consécutive à un AVC, une coactivation anormale des extenseurs du genou et de la cheville est souvent observée à la jambe atteinte lorsque la personne tente de bouger ou encore lors de la marche. Les mécanismes sous-jacents à cette coactivation sont mal compris. Bien que l’AVC entraîne une lésion supraspinale, des évidences démontrent le dysfonctionnement de certains circuits spinaux dans l’hémiparésie. Ce projet de doctorat visait à évaluer : 1) l’excitabilité des circuits spinaux intersegmentaires projetant des extenseurs du genou aux extenseurs de la cheville et 2) si un éventuel dysfonctionnement de ces circuits dans l’hémiparésie est associé à une coactivation anormale des extenseurs du genou et de la cheville lors de contractions statiques et au cours de la marche. La première étude compare la modulation de l’activité réflexe du soléaire suite à la stimulation du nerf fémoral entre des sujets hémiparétiques et sains. Une augmentation de la facilitation hétéronyme de courte latence et une diminution de l’inhibition ultérieure du réflexe H du soléaire ont été observées chez les sujets hémiparétiques. Ces résultats démontrent un dysfonctionnement des circuits intersegmentaires propriospinaux liant le quadriceps au soléaire suite à l’AVC. La deuxième étude démontre que ces changements dans la modulation hétéronyme des sujets hémiparétiques, évaluée au moyen de la méthode complexe basée sur l’activité réflexe du soléaire, sont similaires à ceux observés lorsque la modulation est évaluée en utilisant une méthode plus simple, soit celle de l’activité volontaire du soléaire. De plus, la modulation hétéronyme évaluée par les deux méthodes est corrélée avec l’atteinte motrice à la jambe parétique. La troisième étude a permis de quantifier une augmentation de la coactivation entre les extenseurs du genou et de la cheville lors de contractions volontaires statiques chez des personnes hémiparétiques par rapport à des personnes saines. De plus, le niveau accru de la coactivation involontaire des extenseurs de la cheville lors de l’activation volontaire des extenseurs du genou s’avère corrélé avec la modulation intersegmentaire du côté parétique. La quatrième étude a utilisé un indice temporel, soit l’intervalle entre les pics d’activation électromyographique (PAI), et un indice d’amplitude de coactivation (CAI) pour quantifier une augmentation de la coactivation entre les extenseurs du genou et de la cheville lors de la marche chez des personnes hémiparétiques par rapport à des personnes saines. Ces indices sont corrélés, pour certains groupes musculaires, avec la modulation intersegmentaire modifiée du côté parétique. Finalement, des résultats préliminaires montrent que la vibration mécanique du tendon rotulien (80 Hz) réduit la facilitation intersegmentaire accrue des sujets hémiparétiques. Ce projet doctoral a permis de mettre en lumière un dysfonctionnement de circuits spinaux liant le quadriceps et le soléaire dans l’hémiparésie consécutive à un AVC. Ce changement dans les mécanismes neurophysiologiques de la moelle épinière est corrélé avec des changements fonctionnels. Ainsi, ce dysfonctionnement pourrait contribuer à la coactivation involontaire entre les extenseurs du genou et de la cheville qui fait partie intégrante de la synergie pathologique en extension souvent rencontrée à la jambe parétique lors d’efforts en statique et pendant la marche. Finalement, une étude préliminaire suggère que la vibration mécanique serait une modalité sensorielle prometteuse pour réguler l’hyperexcitabilité des circuits spinaux qui contribuerait aux atteintes motrices chez les personnes hémiparétiques.

Synthèse des connaissances de l’évaluation clinique de la marche en physiothérapie

Travail d'intégration réalisé dans le cadre du cours PHT-6113.

A Synergistic Approach to Human Rights and Public Health Ethics: Effective or a Source of Conflict?

Commentaire / Commentary

Capturing Emergent Semantics from Social Annotation Systems

The ongoing growth of the World Wide Web, catalyzed by the increasing possibility of ubiquitous access via a variety of devices, continues to strengthen its role as our prevalent information and commmunication medium. However, although tools like search engines facilitate retrieval, the task of finally making sense of Web content is still often left to human interpretation. The vision of supporting both humans and machines in such knowledge-based activities led to the development of different systems which allow to structure Web resources by metadata annotations. Interestingly, two major approaches which gained a considerable amount of attention are addressing the problem from nearly opposite directions: On the one hand, the idea of the Semantic Web suggests to formalize the knowledge within a particular domain by means of the "top-down" approach of defining ontologies. On the other hand, Social Annotation Systems as part of the so-called Web 2.0 movement implement a "bottom-up" style of categorization using arbitrary keywords. Experience as well as research in the characteristics of both systems has shown that their strengths and weaknesses seem to be inverse: While Social Annotation suffers from problems like, e. g., ambiguity or lack or precision, ontologies were especially designed to eliminate those. On the contrary, the latter suffer from a knowledge acquisition bottleneck, which is successfully overcome by the large user populations of Social Annotation Systems. Instead of being regarded as competing paradigms, the obvious potential synergies from a combination of both motivated approaches to "bridge the gap" between them. These were fostered by the evidence of emergent semantics, i. e., the self-organized evolution of implicit conceptual structures, within Social Annotation data. While several techniques to exploit the emergent patterns were proposed, a systematic analysis - especially regarding paradigms from the field of ontology learning - is still largely missing. This also includes a deeper understanding of the circumstances which affect the evolution processes. This work aims to address this gap by providing an in-depth study of methods and influencing factors to capture emergent semantics from Social Annotation Systems. We focus hereby on the acquisition of lexical semantics from the underlying networks of keywords, users and resources. Structured along different ontology learning tasks, we use a methodology of semantic grounding to characterize and evaluate the semantic relations captured by different methods. In all cases, our studies are based on datasets from several Social Annotation Systems. Specifically, we first analyze semantic relatedness among keywords, and identify measures which detect different notions of relatedness. These constitute the input of concept learning algorithms, which focus then on the discovery of synonymous and ambiguous keywords. Hereby, we assess the usefulness of various clustering techniques. As a prerequisite to induce hierarchical relationships, our next step is to study measures which quantify the level of generality of a particular keyword. We find that comparatively simple measures can approximate the generality information encoded in reference taxonomies. These insights are used to inform the final task, namely the creation of concept hierarchies. For this purpose, generality-based algorithms exhibit advantages compared to clustering approaches. In order to complement the identification of suitable methods to capture semantic structures, we analyze as a next step several factors which influence their emergence. Empirical evidence is provided that the amount of available data plays a crucial role for determining keyword meanings. From a different perspective, we examine pragmatic aspects by considering different annotation patterns among users. Based on a broad distinction between "categorizers" and "describers", we find that the latter produce more accurate results. This suggests a causal link between pragmatic and semantic aspects of keyword annotation. As a special kind of usage pattern, we then have a look at system abuse and spam. While observing a mixed picture, we suggest that an individual decision should be taken instead of disregarding spammers as a matter of principle. Finally, we discuss a set of applications which operationalize the results of our studies for enhancing both Social Annotation and semantic systems. These comprise on the one hand tools which foster the emergence of semantics, and on the one hand applications which exploit the socially induced relations to improve, e. g., searching, browsing, or user profiling facilities. In summary, the contributions of this work highlight viable methods and crucial aspects for designing enhanced knowledge-based services of a Social Semantic Web.

Finding Spaces for Urban Food Production – Matching Spatial and Stakeholder Analysis with Urban Agriculture Approaches in the Urban Renewal Area of Dortmund-Hörde, Germany

Using the case of an economically declined neighbourhood in the post-industrial German Ruhr Area (sometimes characterized as Germany’s “Rust Belt”), we analyse, describe and conclude how urban agriculture can be used as a catalyst to stimulate and support urban renewal and regeneration, especially from a socio-cultural perspective. Using the methodological framework of participatory action research, and linking bottom-up and top-down planning approaches, a project path was developed to include the population affected and foster individual responsibility for their district, as well as to strengthen inhabitants and stakeholder groups in a permanent collective stewardship for the individual forms of urban agriculture developed and implemented. On a more abstract level, the research carried out can be characterized as a form of action research with an intended transgression of the boundaries between research, planning, design, and implementation. We conclude that by synchronously combining those four domains with intense feedback loops, synergies for the academic knowledge on the potential performance of urban agriculture in terms of sustainable development, as well as the benefits for the case-study area and the interests of individual urban gardeners can be achieved.

Strategies towards evaluation beyond scientific impact

Various research fields, like organic agricultural research, are dedicated to solving real-world problems and contributing to sustainable development. Therefore, systems research and the application of interdisciplinary and transdisciplinary approaches are increasingly endorsed. However, research performance depends not only on self-conception, but also on framework conditions of the scientific system, which are not always of benefit to such research fields. Recently, science and its framework conditions have been under increasing scrutiny as regards their ability to serve societal benefit. This provides opportunities for (organic) agricultural research to engage in the development of a research system that will serve its needs. This article focuses on possible strategies for facilitating a balanced research evaluation that recognises scientific quality as well as societal relevance and applicability. These strategies are (a) to strengthen the general support for evaluation beyond scientific impact, and (b) to provide accessible data for such evaluations. Synergies of interest are found between open access movements and research communities focusing on global challenges and sustainability. As both are committed to increasing the societal benefit of science, they may support evaluation criteria such as knowledge production and dissemination tailored to societal needs, and the use of open access. Additional synergies exist between all those who scrutinise current research evaluation systems for their ability to serve scientific quality, which is also a precondition for societal benefit. Here, digital communication technologies provide opportunities to increase effectiveness, transparency, fairness and plurality in the dissemination of scientific results, quality assurance and reputation. Furthermore, funders may support transdisciplinary approaches and open access and improve data availability for evaluation beyond scientific impact. If they begin to use current research information systems that include societal impact data while reducing the requirements for narrative reports, documentation burdens on researchers may be relieved, with the funders themselves acting as data providers for researchers, institutions and tailored dissemination beyond academia.

Dispute resolution and “environmental” provisions in the WTO: promising developments for environmental matters

En la actualidad, la política internacional tiende hacia la unificación económica y cultural (globalización), en la cual la totalidad de las naciones se encuentran vinculadas por interacciones comerciales. Para que los compromisos adquiridos en materia de protección ambiental sean respetados, el derecho ambiental debe dejar de ser considerado como una disciplina separada y buscar sinergias que le permitan convertirse en un actor importante en las relaciones comerciales. En el presente ensayo se argumenta que el comercio internacional y el derecho ambiental han coevolucionado en las últimas tres décadas, hasta llegar a un balance en el concepto de desarrollo sostenible.Este artículo explora esta coevolución, mientras propone que la Organización Mundial del Comercio (OMC) puede jugar un importante rol en el cumplimiento de los objetivos internacionales de protección ambiental si sus disposiciones “verdes” y su sistema de resolución de conflictos son utilizados para promoverlos, tal como está sucediendo. Para ilustrar este punto, se presenta un breve resumen de los tratados comerciales y ambientales suscritos desde los años setenta, seguido de una explicación de las disposiciones legales de la OMC que pueden ser consideradas como “verdes”, con el fin de hallar puntos de convergencia que puedan ser utilizados por los países miembros no solo para justificar la adopción de normativas domésticas de protección ambiental, sino también para instar a los otros signatarios en el cumplimiento de sus obligaciones en esta área.

El Outsourcing en la dinámica de sistemas hacia mercados extranjeros

Este trabajo recopila literatura académica relevante sobre estrategias de entrada y metodologías para la toma de decisión sobre la contratación de servicios de Outsourcing para el caso de empresas que planean expandirse hacia mercados extranjeros. La manera en que una empresa planifica su entrada a un mercado extranjero, y realiza la consideración y evaluación de información relevante y el diseño de la estrategia, determina el éxito o no de la misma. De otro lado, las metodologías consideradas se concentran en el nivel estratégico de la pirámide organizacional. Se parte de métodos simples para llegar a aquellos basados en la Teoría de Decisión Multicriterio, tanto individuales como híbridos. Finalmente, se presenta la Dinámica de Sistemas como herramienta valiosa en el proceso, por cuanto puede combinarse con métodos multicriterio.

Estudio de caso: La Marcha Patriótica como movimiento social y político: Análisis de la naturaleza de un actor en construcción a partir de su accionar y sus reivindicaciones. 2010 - 2012.

La presente investigación tiene como objetivo realizar una aproximación interpretativa a la Marcha Patriótica [MP] a través de tres ejes, a saber, Partido Político, Movimiento Político y Movimiento Social. Para desarrollarlo, se realizó una caracterización del contexto con el interés de identificar las situaciones contributivas a la génesis de la MP. En este contexto, se logró establecer que la situación más importante y determinante fueron los diálogos de paz de La Habana entre el gobierno de Colombia y la guerrilla de las Fuerzas Armadas Revolucionarias de Colombia. Posteriormente, se realizó la descripción de los tres ejes de interpretación y la definición de cómo serían entendidos para efectos del estudio de caso. Finalmente, se procedió con una caracterización de la MP a través de los ejes y se concluyó con una explicación amplia que dio como resultado la incorporación de nuevos elementos de análisis. Lo anterior, permitió explicar a la MP a partir de sus sectores, sus reivindicaciones, su accionar, los movimientos que la componen y los actores con los que se relaciona.

Integració de sistemes estandarditzats de gestió: anàlisi empírica

Els sistemes de gestió permeten millorar l'eficiència de les organitzacions i en aquest context, una organització pot tenir implantats múltiples sistemes. La forma preferible de gestionar-los és integrant-los, perquè s'aprofiten les sinèrgies existents entre sistemes. Existeixen molt pocs estudis empírics que analitzin la integració de sistemes. Així, l'objectiu d'aquesta tesi és conèixer i analitzar empíricament com integren les empreses els sistemes i com realitzen les auditories d'aquests. Les conclusions de l'anàlisi empírica realitzada són que les empreses:(1)integren majoritàriament els sistemes a un determinat nivell, i sembla que els models de gestió utilitzats i l'ordre d'implantació dels sistemes, condicionen aquest nivell,(2)duen a terme, majoritàriament, auditories del sistema integrades, essent el nivell d'integració de les internes superior al de les externes, i(3)en alguns aspectes, sembla que la integració de les auditories externes, està relacionada amb el nivell d'integració dels sistemes.

Determinants of portuguese wine & enotourism consumer behaviour

This study tries to understand what needs to be done to improve value perceptions and wine usage (1) Change the Portuguese wine and enotourism industry profile to adjust to huge competitive marketplace because it is still production-based; more sales than marketing oriented and the market data are less important then production and sales ones; (2) Enhance strongly the relationship between the wine and enotourism company and final consumers by “management synergies”; high “innovativeness to market”;“marketing research” and by an effective brand strategy. In this line, this paper provides an overview about strategic factors that determine the Portuguese wine and enotourism decision making process. The results of this research enable the essential features of a consumer profile of purchase and consumption to be obtained with respect to: (1) the structure of attributes - intrinsic and extrinsic - that Portuguese still wine consumers best recognise and value in determining its quality, (2) the motivational structures that encourage and guide them in their decision making process when purchasing and consuming wine and enotourism services, (3) the anticipated effect of interaction between different situations of consumption with different price bands.

O empreendedorismo e a inovação na saúde, factores potenciadores de novos projetos

O objetivo geral deste trabalho é investigar o empreendedorismo e a inovação, assim como a forma como estes instrumentos se têm ligado, ou podem vir a ligar-se, à atividade da saúde potenciando novos projetos empresariais inovadores com elevados níveis de competitividade e rentabilidade, numa lógica de criação de um modelo que sintetize estes instrumentos e os potencie para resultados noutros projetos empresariais. No seu desenvolvimento, pretende-se compreender e melhorar a influência positiva que o empreendedorismo e a inovação têm na área da saúde e compreender a influência destes instrumentos como fatores potenciadores de novos projetos contribuindo para a regeneração dos tecidos empresariais, quer ao nível da criação de novas empresas inovadoras, quer ao nível da modernização, reposicionamento ou reorientação de empresas existentes. O objetivo específico desta investigação sobre empreendedorismo e inovação na saúde, como fatores potenciadores de novos projetos, pode evidenciar sinais de êxito mais evidentes, que permita tirar ilações da importância das sinergias entre empreendedorismo e inovação, nas suas várias vertentes da saúde, que alavanquem novas oportunidades para projetos empresariais, sustentáveis e com forte probabilidade de sucesso, muitos deles já identificados, mas ainda não desenvolvidos quer por potenciais empreendedores ou investidores.

Exporting construction professional services in a global service economy

Globalisation has prompted increasing numbers of construction profes-sional services (CPS) firms to internationalise and export their services. The driver has been twofold; firstly to increase turnover/profits and sec-ondly, to minimise the risk of a reliance on working in a single domestic market which has a fluctuating demand. Secondly, where firms have out-grown their domestic market, and in order to expand, they must export overseas. There has been little research into the way CPS firms operate overseas, yet construction represents approximately 10% of global GDP; this means that understanding CPS firms is important. This paper investigates how CPS firms internationalise and the drivers that impact their decisions and operations overseas. A survey was undertaken and interviews conducted that showed CPS firms are project driven, in-vesting heavily in the process of seeking work/bidding for projects, and are very focused on delivering projects with minimum risk. Increasing foreign ownership, changing procurement approaches and more consolidation of CPS firms in the global marketplace present a changing business land-scape. The research develops a framework of tangible and intangible factors, such as competencies, business organisation culture, leadership and reputation in order to better understand how CPS firms export their ser-vices. Whilst all CPS firms share the same framework of factors, the re-sulting synergies are different not only for each firm but also for each pro-ject. The knowledge-intensive and project-based nature of CPS firms presents a challenge in understanding the way they operate in the global service economy.

Farmer experience of pluralistic agricultural extension, Malawi

Purpose: Malawi’s current extension policy supports pluralism and advocates responsiveness to farmer demand. We investigate whether smallholder farmers’ experience supports the assumption that access to multiple service providers leads to extension and advisory services that respond to the needs of farmers. Design/methodology/approach: Within a case study approach, two villages were purposively selected for in-depth qualitative analysis of available services and farmers’ experiences. Focus group discussions were held separately with male and female farmers in each village, followed by semi-structured interviews with 12 key informants selected through snowball sampling. Transcripts were analysed by themes and summaries of themes were made from cross case analysis. Findings: Farmers appreciate having access to a variety of sources of technical advice and enterprise specific technology. However, most service providers continue to dominate and dictate what they will offer. Market access remains a challenge, as providers still emphasize pushing a particular technology to increase farm productivity rather than addressing farmers’ expressed needs. Although farmers work in groups, providers do not seek to strengthen these to enable active interaction and to link them to input and produce markets. This limits farmers’ capacity to continue with innovations after service providers pull out. Poor coordination between providers limits exploitation of potential synergies amongst actors. Practical implications: Services providers can adapt their approach to engage farmers in discussion of their needs and work collaboratively to address them. At a system level, institutions that have a coordination function can play a more dynamic role in brokering interaction between providers and farmers to ensure coverage and responsiveness. Originality/value: The study provides a new farmer perspective on the implementation of extension reforms.

Terrestrial biogeochemical feedbacks in the climate system

The terrestrial biosphere is a key regulator of atmospheric chemistry and climate. During past periods of climate change, vegetation cover and interactions between the terrestrial biosphere and atmosphere changed within decades. Modern observations show a similar responsiveness of terrestrial biogeochemistry to anthropogenically forced climate change and air pollution. Although interactions between the carbon cycle and climate have been a central focus, other biogeochemical feedbacks could be as important in modulating future climate change. Total positive radiative forcings resulting from feedbacks between the terrestrial biosphere and the atmosphere are estimated to reach up to 0.9 or 1.5 W m−2 K−1 towards the end of the twenty-first century, depending on the extent to which interactions with the nitrogen cycle stimulate or limit carbon sequestration. This substantially reduces and potentially even eliminates the cooling effect owing to carbon dioxide fertilization of the terrestrial biota. The overall magnitude of the biogeochemical feedbacks could potentially be similar to that of feedbacks in the physical climate system, but there are large uncertainties in the magnitude of individual estimates and in accounting for synergies between these effects.