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Slow Process (slow + process)
Selected AbstractsHARMONIZING REGULATIONS FOR BIOMEDICAL RESEARCH: A CRITICAL ANALYSIS OF THE US AND VENEZUELAN SYSTEMSDEVELOPING WORLD BIOETHICS, Issue 3 2008DANNIE DI TILLIO-GONZALEZ ABSTRACT This article aims to compare the national legal systems that regulate biomedical research in an industrialized country (United States) and a developing country (Venezuela). A new international order is emerging in which Europe, Japan and the United States (US) are revising common guidelines and harmonizing standards. In this article, we analyze , as an example , the US system. This system is controlled by a federal agency structured to regulate research funded by the federal government uniformly, either in the US or abroad. In contrast, in Venezuela, a developing country, the creation of a centralized system is a slow process. Different types of ethical committees review research projects using non-uniform criteria. Consequently, various parallel organizations that conduct biomedical research, such as universities, research institutes and private hospitals have diverse regulations operating at a local level. Thus, the most relevant difference between the Venezuelan and the US systems is the degree of standardization. In the US, the review process is performed by institutional review boards (IRBs), which have a similar organization and maintain relationships with a centralized agency, following standard regulations. Although new proposals for establishing national regulations are currently being considered in Venezuela, the success of these initiatives will depend on promoting governmental efforts to create a more structured centralized system supported by a national regulatory framework. This system will need governmental financial support at all levels. This article proposes an integrated system to regulate research with human participants in Venezuela and other developing countries. [source] After Cancún: what next for agricultural subsidies?EUROCHOICES, Issue 3 2003Tim Josling Summary After Cancún: what next for agriculturalsubsidies? The collapse of the Ministerial in Cancún highlighted the enhanced role of the developing countries in the WTO and the reduced ability of the US and the EU to manage the trade system. One aspect of these changes has been that developing countries have taken much more interest in the level of domestic support in developed countries. Developed countries believe that the shift of support from production-linked to decoupled instruments has had a positive impact on trade. Developing countries maintain that this reform has not helped them, and has perpetuated inequities in the trade system. Research suggests that the output effect of decoupled support is limited, if not negligible. Such decoupling may be necessary to reform domestic polices. Additionally, domestic policies are being challenged by developing countries using the trade litigation of the WTO. But such challenges risk undermining support for the WTO. Until agreement is reached on these issues there will be little progress in further agricultural trade reform. A political solution must be found that continues the slow process of improvement of domestic farm policies and at the same time offers hope to developing countries that they will benefit from the improvement in the trade conditions for agricultural products. Après Cancún:quel avenir pour les subventions? L'échec de la conférence ministérielle de Cancun met en évidence !e rôle accru des pays en voie de développement à l'OMC, ainsi que la faible aptitude des Etats-Unis et de l'Europe à gérer le système des échanges internationaux. Ces changements impliquent que les pays en voie de développement s'intéressent de plus en plus aux niveaux de protection internes des pays développés. Les pays développés croient que le glissement des aides vers plus de découplage aura eu un effet positif sur les échanges. Mais les pays en voie de développement continuent à penser que ces réformes ne les ont pas aidés, et qu'elles ont perpétué les inégalités du commerce mondial. Le travail présenté ici semble montrer que l'effet du découplage sur l'offre est très faible, voire nul. Peut-être le decouplage est-il utile pour la réforme des politiques internes. Mais, au delà, ces politiques internes sont mises en cause par les pays en voie de développement, qui utilisent à leur encontre les ressources de procédure mises à leur disposition par l'OMC. De telles mises en cause sont de nature à détruire le soutien de l'opinion à l'OMC. II ne faut pas s'attendre à beaucoup de progrès dans les réformes du commerce international agricole tant qu'on n'aura pas trouve un accord sur ces questions. II est done necessaire d'élaborer des solutions qui confortent le lent progrès des politiques internes des pays developpes, tout en offrant aux pays en voie de développement 1, espoir de bénéficier de l'amélioration des conditions des échanges agricoles. Nach Cancún: Was geschieht als nächstes mitAgrarsubventionen? Das Scheitern des Ministerialtreffensin Cancún hob die verbesserte Position der Entwicklungsländer in der WTO und die verminderte Fähigkeit der USA und der EU hervor, das Handelssystem zu lenken. Finer der Aspekte dieser Veränderungen bestand darin, dass die Entwicklungsländer ein sehr viel größeres Interesse am Ausmaß der Inlandsstützung in Industrieländern gezeigt haben. Die Industrieländer glauben, dass sich der Schritt von einer produktionsgebundenen Inlandsstützung hin zu einer entkoppelten Inlandsstützung positiv auf den Handel ausgewirkt hat. Die Entwicklungsländer behaupten jedoch, dass ihnen diese Reform nicht geholfen habe und dass so Ungerechtigkeiten im Handelssystem aufrecht erhalten würden. Forschungsergebnisse legen es nahe, dass sich die entkoppelte Inlandsstützung sehr begrenzt, möglicherweise nur geringfügig, auf die Produktion auswirkt. Eine solche Entkopplung ist möglicherweise notwendig, urn inländische Politikmaßnahmen zu reformieren. Zusátzlich werden die inländischen Politikmaßnahmen von den Entwicklungsländern zur Zeit im Rahmen der WTO-Verfahren zur Beilegung von Handelsstreitigkeiten angefochten. Solche Anfechtungen bergen jedoch immer das Risiko einer abgeschwächten Unterstützung für die WTO. Bis in diesen Punkten Einigkeit herrscht, wird es nur geringe Fortschritte für die Agrarhandelsreformen geben. Es muss eine politische Lösung gefunden werden, welche den langsamen Verbesserungsprozess bei den inländischen Agrarpolitikmaßnahmen voran treibt und welche die Entwicklungsländer zugleich hoffen lässt, von der Verbesserung der Handelsbedingungen für landwirtschaftliche Erzeugnisse profitieren zu können. [source] Intellectual abilities and white matter microstructure in development: A diffusion tensor imaging studyHUMAN BRAIN MAPPING, Issue 10 2010Christian K. Tamnes Abstract Higher-order cognitive functions are supported by distributed networks of multiple interconnected cortical and subcortical regions. Efficient cognitive processing depends on fast communication between these regions, so the integrity of the connections between them is of great importance. It is known that white matter (WM) development is a slow process, continuing into adulthood. While the significance of cortical maturation for intellectual development is described, less is known about the relationships between cognitive functions and maturation of WM connectivity. In this cross-sectional study, we investigated the associations between intellectual abilities and development of diffusion tensor imaging (DTI) derived measures of WM microstructure in 168 right-handed participants aged 8,30 years. Independently of age and sex, both verbal and performance abilities were positively related to fractional anisotropy (FA) and negatively related to mean diffusivity (MD) and radial diffusivity (RD), predominantly in the left hemisphere. Further, verbal, but not performance abilities, were associated with developmental differences in DTI indices in widespread regions in both hemispheres. Regional analyses showed relations with both FA and RD bilaterally in the anterior thalamic radiation and the cortico-spinal tract and in the right superior longitudinal fasciculus. In these regions, our results suggest that participants with high verbal abilities may show accelerated WM development in late childhood and a subsequent earlier developmental plateau, in contrast to a steadier and prolonged development in participants with average verbal abilities. Longitudinal data are needed to validate these interpretations. The results provide insight into the neurobiological underpinnings of intellectual development. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [source] Vocabulary acquisition: acquiring depth of knowledge through network buildingINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 2 2000Kirsten Haastrup Lexical progression involves a process of network building whereby learners acquire depth of lexical knowledge. This includes the knowledge of a word's different sense relations, paradigmatic as well as syntagmatic, to other words. The focus of this article is a longitudinal study of young foreign language learners'acquisition of English adjectives. A series of tasks were developed to tap lexical relations between adjectives of emotion, e.g. the paradigmatic relations of synonymy and gradation, in order to study how a particular adjective such as thrilled finds its place among other near-synonymous expressions in the subfield HAPPY. Data were collected over a three-year period, so it was possible to study learner performance over time as well as across tasks. Findings revealed that network building is an extremely slow process and that some subfields are much more difficult than others. With the help of qualitative analyses, an account is given of the way in which particular adjectives become enmeshed , or fail to become enmeshed , in the meaning network of related words in the lexical field. [source] Review Article: A new wrinkle on old skin: the role of elastic fibres in skin ageingINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2010A. K. Langton Synopsis Cutaneous ageing is the result of two distinct, biological processes which may occur concurrently: (i) the passage of time, termed intrinsic ageing and (ii) environmental influences, termed extrinsic ageing. Intrinsic ageing of the skin is a slow process which causes changes in tissue structure and impairs function in the absence of additional biological, chemical and physical factors. The clinical features of intrinsically aged skin are not usually evident until old age when, although smooth and unblemished, the skin surface appears pale and is characterized by fine wrinkles with occasional exaggerated expression lines. Functionally, intrinsically aged skin is dry and less elastic than more youthful skin. In contrast, extrinsically aged skin is exemplified by deep, coarse wrinkles, mottled hyperpigmentation and a marked loss of elasticity and recoil. The two major environmental influences which induce extrinsic ageing are: (i) chronic exposure to solar ultraviolet (UV) irradiation (termed photoageing) and (ii) smoking. This review discusses the changes associated with the ageing process in the skin, with particular emphasis on the role played by the elastic fibre network in maintaining dermal function. The review concludes with a discussion of a short-term assay for independent assessment of the efficacy of anti-ageing cosmetic products using the elastic fibre component fibrillin-1 as a biomarker of extracellular matrix repair. Résumé Le vieillissement Cutané est le résultat de deux processus biologiques distincts, qui peuvent se produire concurremment : i) le passage de temps, désigné comme vieillissement intrinsèque et ii) les influences environnementales, désignées comme vieillissement extrinsèque. Le vieillissement intrinsèque de la peau est un processus lent provoquant des changements de la structure et détériorant la fonction tissulaire sans facteurs biologiques, chimiques ou physiques supplémentaires. Les caractéristiques cliniques de la peau intrinsèquement âgée sont peu visibles avant la vieillesse où, bien que lisse et impeccable, la surface de la peau apparaît pâle et marquée par des rides notables et des lignes d'expression exagérées. Au niveau fonctionnel, la peau intrinsèquement âgée est sèche et moins d'élastique que la peau plus jeune. Au contraire, la peau extrinsèquement âgée est caractérisée par des rides profondes, grossières, une hyperpigmentation en taches et une perte marquée d'élasticité. Les deux influences environnementales majeures à l'origine du vieillissement extrinsèque sont : i) l'exposition chronique aux ultra-violets (UV) et ii) l'exposition tabagique. Cette revue envisage les changements associés au processus de vieillissement cutané, avec une attention particulière sur le rôle joué par le réseau élastique dans le maintien de la fonction dermique. Cette analyse se termine par une discussion à propos d'un essai d'évaluation de l'efficacité de produits cosmétiques anti-âges utilisant un composant de fibre élastique la fibrillin-1 comme bio marqueur de la réparation de la matrice extracellulaire. [source] The zebrafish (Danio rerio) caudal complex , a model to study vertebral body fusionJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010A. Bensimon-Brito Summary Impairment of segmentation during embryonic development leads to congenital fusion of vertebrae. Nevertheless, vertebral fusion can also occur during post-embryonic life. Fusion can cause reduction in mobility and may be pathological, but it can also be part of normal development and mechanically required, such as in the teleost caudal skeleton, or in the tetrapod sacrum. Using a series of closely spaced ontogenetic stages of zebrafish, stained for mineralized (Alizarin red) and cartilaginous (Alcian blue) structures, we have characterized all fusions occurring during the formation of the caudal skeleton. The urostyle results from the vertebral fusion of the compound centrum preural1-ural1 [PU1++U1] and ural2 [U2+]. Based on developmental and morphological characters: (i) number of vestigial haemal arches, (ii) occasional presence of a haemal arch rudiment, (iii) occasional individuals with separate centra rudiments or distinct mineralization time points, and (iv) evidence for internal separation, we propose that the urostyle forms as a fusion product of five, and not three vertebral centra, as previously described. The last fusion to occur in development, between the compound centrum [PU1++U1] and U2+, is a relatively slow process that typically occurs in Cypriniformes and Salmoniformes and is therefore considered reliable to monitor the fusion process. The vertebrae adjacent to the urostyle, preurals 2 and 3, are highly susceptible to fusion, and thus inadequate as a negative control to fusion, in contrast to trunk vertebrae, where fusion is never observed. With this we have established the basis for a new model to study vertebral fusion and to unravel cellular and molecular events underlying this process. [source] Absolute measurement of internal volume changes inside the pulse damper: Discrepancy between delay and dwell volumesJOURNAL OF SEPARATION SCIENCE, JSS, Issue 10 2010Eduard Rogatsky Abstract We have developed a novel technique for the absolute determination of the mobile phase volume stored inside of a variable volume pulse damper at different pressures. Using an Agilent HPLC pulse damper we found a linear volume increase of ,1,,L/bar. We found that pump pressurization is a relatively slow process and takes ,1,min to reach 90% and takes ,2,min to reach 99% equilibration at flow rates below 1,mL/min. During pump pressurization, column flow rate will be less than the pre-set, since part of the mobile phase is retained inside of the pulse damper. During our experiments we observed a discrepancy between data obtained by UV techniques and direct absolute measurements. This difference can be explained by a fundamental difference between the gradient delay volume and dead (dwell) volume. [source] Characteristics of sex-biased dispersal and gene flow in coastal river otters: implications for natural recolonization of extirpated populationsMOLECULAR ECOLOGY, Issue 3 2002G. M. Blundell Abstract River otters (Lontra canadensis) were extirpated from much of their historic distribution because of exposure to pollution and urbanization, resulting in expansive reintroduction programmes that continue today for this and other species of otters worldwide. Bioaccumulation of toxins negatively affects fecundity among mustelids, but high vagility and different dispersal distances between genders may permit otter populations to recover from extirpation caused by localized environmental pollution. Without understanding the influence of factors such as social structure and sex-biased dispersal on genetic variation and gene flow among populations, effects of local extirpation and the potential for natural recolonization (i.e. the need for translocations) cannot be assessed. We studied gene flow among seven study areas for river otters (n = 110 otters) inhabiting marine environments in Prince William Sound, Alaska, USA. Using nine DNA microsatellite markers and assignment tests, we calculated immigration rates and dispersal distances and tested for isolation by distance. In addition, we radiotracked 55 individuals in three areas to determine characteristics of dispersal. Gender differences in sociality and spatial relationships resulted in different dispersal distances. Male river otters had greater gene flow among close populations (within 16,30 km) mostly via breeding dispersal, but both genders exhibited an equal, low probability of natal dispersal; and some females dispersed 60,90 km. These data, obtained in a coastal environment without anthropogenic barriers to dispersal (e.g. habitat fragmentation or urbanization), may serve as baseline data for predicting dispersal under optimal conditions. Our data may indicate that natural recolonization of coastal river otters following local extirpation could be a slow process because of low dispersal among females, and recolonization may be substantially delayed unless viable populations occurred nearby. Because of significant isolation by distance for male otters and low gene flow for females, translocations should be undertaken with caution to help preserve genetic diversity in this species. [source] Crystallization and melting behavior of zenite thermotropic liquid crystalline polymers,POLYMER ENGINEERING & SCIENCE, Issue 2 2002K. P. Pramoda The crystallization and melting behavior of a DuPont ZeniteTM series, namely, Z 6000 and Z 8000B, thermotropic liquid crystalline polymer (TLCP) have been investigated by differential scanning calorimetry (DSC). Both, non-isothermal and isothermal crystallizations were carried out. From the non-isothermal experiments, the crystallization temperature was found to be 234°C for a cooling rate of 10°C/min whereas it was only 228°C for 40°C/min for Z 8000B, and was found to be 296°C and 290°C, respectively, for Z 6000. In the isothermal experiment both the thermal and crystallization behaviors were studied as a function of the annealing temperature and annealing time. Two types of transition processes were evidence in the low temperature region of the isothermal crystallization. One is fast transition, which may be regarded as liquid crystal transition, and is characterized by the enthalpy, which is independent of annealing time. The other is slow process, related to crystal perfection, and it shows increases in the transition temperature and enthalpy, which is dependent on annealing time. [source] Microbial systems engineering: First successes and the way aheadBIOESSAYS, Issue 4 2010Sven Dietz Abstract The first promising results from "streamlined," minimal genomes tend to support the notion that these are a useful tool in biological systems engineering. However, compared with the speed with which genomic microbial sequencing has provided us with a wealth of data to study biological functions, it is a slow process. So far only a few projects have emerged whose synthetic ambition even remotely matches our analytic capabilities. Here, we survey current technologies converging into a future ability to engineer large-scale biological systems. We argue that the underlying synthetic technology, de novo DNA synthesis, is already rather mature , in particular relative to the scope of our current synthetic ambitions. Furthermore, technologies towards rationalizing the design of the newly synthesized DNA fragment are emerging. These include techniques to implement complex regulatory circuits, suites of parts on a DNA and RNA level to fine tune gene expression, and supporting computational tools. As such DNA fragments will, in most cases, be destined for operating in a cellular context, attention has to be paid to the potential interactions of the host with the functions encoded on the engineered DNA fragment. Here, the need of biological systems engineering to deal with a robust and predictable bacterial host coincides with current scientific efforts to theoretically and experimentally explore minimal bacterial genomes. [source] How do you initiate oestrogen therapy in a girl who has not undergone puberty?CLINICAL ENDOCRINOLOGY, Issue 1 2009Peter C. Hindmarsh Summary The physiology of puberty needs to be taken into consideration in the induction of puberty. Puberty is a relatively slow process and replacement therapy should mimic this. Long-term maintenance requires careful monitoring and long-term assessment of risk-benefit. This has not been appreciably defined in the adolescent population. Options for fertility need careful consideration and may depend on the adequacy of pubertal induction in terms of uterine development. A number of regimens are available for pubertal induction but the lack of comparisons makes it difficult to advocate for a particular regimen. There remain a number of areas of uncertainty, and future studies need to consider these issues and whether there are cardiovascular risk factor advantages to certain preparations. The long-term risks of breast and gynaecological malignancy remain uncertain. Long-term cohort studies are required to address these issues. [source] | ||||||||||||||||