18 resultados para Intellectual and development deficit
em Université de Lausanne, Switzerland
Resumo:
Eusociality is taxonomically rare, yet associated with great ecological success. Surprisingly, studies of environmental conditions favouring eusociality are often contradictory. Harsh conditions associated with increasing altitude and latitude seem to favour increased sociality in bumblebees and ants, but the reverse pattern is found in halictid bees and polistine wasps. Here, we compare the life histories and distributions of populations of 176 species of Hymenoptera from the Swiss Alps. We show that differences in altitudinal distributions and development times among social forms can explain these contrasting patterns: highly social taxa develop more quickly than intermediate social taxa, and are thus able to complete the reproductive cycle in shorter seasons at higher elevations. This dual impact of altitude and development time on sociality illustrates that ecological constraints can elicit dynamic shifts in behaviour, and helps explain the complex distribution of sociality across ecological gradients.
Resumo:
Zero correlation between measurement error and model error has been assumed in existing panel data models dealing specifically with measurement error. We extend this literature and propose a simple model where one regressor is mismeasured, allowing the measurement error to correlate with model error. Zero correlation between measurement error and model error is a special case in our model where correlated measurement error equals zero. We ask two research questions. First, we wonder if the correlated measurement error can be identified in the context of panel data. Second, we wonder if classical instrumental variables in panel data need to be adjusted when correlation between measurement error and model error cannot be ignored. Under some regularity conditions the answer is yes to both questions. We then propose a two-step estimation corresponding to the two questions. The first step estimates correlated measurement error from a reverse regression; and the second step estimates usual coefficients of interest using adjusted instruments.
Resumo:
BACKGROUND: To estimate the prevalence of undernutrition among children with profound intellectual and multiple disabilities (PIMD) and to explore its influence on quality of life. METHODS: Seventy-two children with PIMD (47 male; 25 female; age range 2 to 15 years 4 months; mean age 8.6, SD 3.6) underwent an anthropometric assessment, including body weight, triceps skinfold thickness, segmental measures and recumbent length. Undernutrition was determined using tricipital skinfold percentile and z-scores of weight-for-height and height-for-age. The quality of life of each child was evaluated using the QUALIN questionnaire adapted for profoundly disabled children. RESULTS: Twenty-five children (34.7%) were undernourished and seven (9.7%) were obese. Among undernourished children only eight (32 %) were receiving food supplements and two (8%) had a gastrostomy, of which one was still on a refeeding programme. On multivariate analysis, undernutrition was one of the independent predictors of lower quality of life. CONCLUSION: Undernutrition remains a matter of concern in children with PIMD. There is a need to better train professionals in systematically assessing the nutritional status of profoundly disabled children in order to start nutritional management when necessary.
Resumo:
In its fifth decade of existence, the construct of schizotypy is recapturing the early scientific interest it attracted when Paul E. Meehl (1920-2003), who coined the term, pioneered the field of schizotypy research. The International Lemanic Workshop on Schizotypy, hosted at the University of Geneva in December 2013, recently offered an opportunity to address some of the fundamental questions in contemporary schizotypy research and situate the construct in the greater scheme of future scientific projects on schizophrenia and psychological health research. What kind of knowledge has schizotypy research provided in furthering our understanding of schizophrenia? What types of questions can schizotypy research tackle, and which are the conceptual and methodological frameworks to address them? How will schizotypy research contribute to future scientific endeavors? The International Lemanic Workshop brought together leading experts in the field around the tasks of articulating the essential findings in schizotypy research, as well as providing some key insights and guidance to face scientific challenges of the future. The current supplement contains 8 position articles, 4 research articles, and 1 invited commentary that outline the state of the art in schizotypy research today
Resumo:
Aleppo pine (Pinus halepensis Mill.) is a relevant conifer species for studying adaptive responses to drought and fire regimes in the Mediterranean region. In this study, we performed Illumina next-generation sequencing of two phenotypically divergent Aleppo pine accessions with the aims of (i) characterizing the transcriptome through Illumina RNA-Seq on trees phenotypically divergent for adaptive traits linked to fire adaptation and drought, (ii) performing a functional annotation of the assembled transcriptome, (iii) identifying genes with accelerated evolutionary rates, (iv) studying the expression levels of the annotated genes and (v) developing gene-based markers for population genomic and association genetic studies. The assembled transcriptome consisted of 48,629 contigs and covered about 54.6 Mbp. The comparison of Aleppo pine transcripts to Picea sitchensis protein-coding sequences resulted in the detection of 34,014 SNPs across species, with a Ka /Ks average value of 0.216, suggesting that the majority of the assembled genes are under negative selection. Several genes were differentially expressed across the two pine accessions with contrasted phenotypes, including a glutathione-s-transferase, a cellulose synthase and a cobra-like protein. A large number of new markers (3334 amplifiable SSRs and 28,236 SNPs) have been identified which should facilitate future population genomics and association genetics in this species. A 384-SNP Oligo Pool Assay for genotyping with the Illumina VeraCode technology has been designed which showed an high overall SNP conversion rate (76.6%). Our results showed that Illumina next-generation sequencing is a valuable technology to obtain an extensive overview on whole transcriptomes of nonmodel species with large genomes.
Resumo:
Plants are sessile and photo-autotrophic; their entire life cycle is thus strongly influenced by the ever-changing light environment. In order to sense and respond to those fluctuating conditions higher plants possess several families of photoreceptors that can monitor light from UV-B to the near infrared (far-red). The molecular nature of UV-B sensors remains unknown, red (R) and far-red (FR) light is sensed by the phytochromes (phyA-phyE in Arabidopsis) while three classes of UV-A/blue photoreceptors have been identified: cryptochromes, phototropins, and members of the Zeitlupe family (cry1, cry2, phot1, phot2, ZTL, FKF1, and LKP2 in Arabidopsis). Functional specialization within photoreceptor families gave rise to members optimized for a wide range of light intensities. Genetic and photobiological studies performed in Arabidopsis have shown that these light sensors mediate numerous adaptive responses (e.g., phototropism and shade avoidance) and developmental transitions (e.g., germination and flowering). Some physiological responses are specifically triggered by a single photoreceptor but in many cases multiple light sensors ensure a coordinated response. Recent studies also provide examples of crosstalk between the responses of Arabidopsis to different external factors, in particular among light, temperature, and pathogens. Although the different photoreceptors are unrelated in structure, in many cases they trigger similar signaling mechanisms including light-regulated protein-protein interactions or light-regulated stability of several transcription factors. The breath and complexity of this topic forced us to concentrate on specific aspects of photomorphogenesis and we point the readers to recent reviews for some aspects of light-mediated signaling (e.g., transition to flowering).
Resumo:
We report new polymorphic microsatellites for three species of Palearctic green toads (Bufo viridis subgroup): 10 in B. balearicus and seven each in B. siculus and B. boulengeri. Diversity at these loci, measured for 27 B. balearicus, 23 B. siculus and 11 B. boulengeri, ranged from low to high (two to 10 alleles). Mitotyping primers, specific to the control region, which allow fast screening of parapatric Sicilian endemic B. siculus and Italian mainland-origin B. balearicus, were developed.
Resumo:
We have demonstrated that cortical cell autografts might be a useful therapy in two monkey models of neurological disease: motor cortex lesion and Parkinson's disease. However, the origin of the useful transplanted cells obtained from cortical biopsies is not clear. In this report we describe the expression of doublecortin (DCX) in these cells based on reverse-transcription polymerase chain reaction (RT-PCR) and immunodetection in the adult primate cortex and cell cultures. The results showed that DCX-positive cells were present in the whole primate cerebral cortex and also expressed glial and/or neuronal markers such as glial fibrillary protein (GFAP) or neuronal nuclei (NeuN). We also demonstrated that only DCX/GFAP positive cells were able to proliferate and originate progenitor cells in vitro. We hypothesize that these DCX-positive cells in vivo have a role in cortical plasticity and brain reaction to injury. Moreover, in vitro these DCX-positive cells have the potential to reacquire progenitor characteristics that confirm their potential for brain repair.
Resumo:
It has been known for some time that different arbuscular mycorrhizal fungal (AMF) taxa confer differences in plant growth. Although genetic variation within AMF species has been given less attention, it could potentially be an ecologically important source of variation. Ongoing studies on variability in AMF genes within Glomus intraradices indicate that at least for some genes, such as the BiP gene, sequence variability can be high, even in coding regions. This suggests that genetic variation within an AMF may not be selectively neutral. This clearly needs to be investigated in more detail for other coding regions of AMF genomes. Similarly, studies on AMF population genetics indicate high genetic variation in AMF populations, and a considerable amount of variation seen in phenotypes in the population can be attributed to genetic differences among the fungi. The existence of high within-species genetic variation could have important consequences for how investigations on AMF gene expression and function are conducted. Furthermore, studies of within-species genetic variability and how it affects variation in plant growth will help to identify at what level of precision ecological studies should be conducted to identify AMF in plant roots in the field. A population genetic approach to studying AMF genetic variability can also be useful for inoculum development. By knowing the amount of genetic variability in an AMF population, the maximum and minimum numbers of spores that will contain a given amount of genetic diversity can be estimated. This could be particularly useful for developing inoculum with high adaptability to different environments.
Resumo:
Résumé Cette étude examine les changements précoces dans le Style Défensif Maladaptatif (SDM), le développement de l'alliance thérapeutique et la relation entre le SDM et l'alliance au cours d'une psychothérapie psychodynamique ultra-brève. Soixante-huit patients ambulatoires du centre de consultation psychiatrique et psychothérapique ont bénéficié d'une intervention psychodynamique en quatre séances. Les mesures des défenses et de l'alliance étaient effectuées à la première et à la dernière séance. Les patients qui ont débuté l'intervention avec une alliance faible et qui l'ont terminée avec une alliance haute (groupe de patients avec une alliance de croissance linéaire) ont diminué leur utilisation de défenses maladaptatives de manière significative au cours de la thérapie, alors que ce n'a pas été le cas pour les patients des groupes à alliances haute-stable et basse-stable. Les résultats ont montré qu'à la fin de l'intervention, le SDM et l'alliance étaient corrélés pour tous les patients. Cette corrélation intéressait plus particulièrement le groupe avec une alliance de croissance linéaire. Ces résultats suggèrent, que le développement de l'alliance thérapeutique reflètent le travail de collaboration entre le patient et son thérapeute alors qu'ils essayent de mieux comprendre les causes de la crise du patient. Cette compréhension peut aider à réduire les défenses initialement activées pour permettre au patient de se défendre de l'anxiété et d'un sentiment de détresse. Abstract This study examined the early change in Maladaptive Defense Style (MDS), the development of the Therapeutic Alliance, and the relationship between MDS and alliance, in a short psychodynamic intervention. Sixty-eight outpatients from a psychiatric clinic completed a four-session psychodynamic intervention. Defense and alliance measures were collected at the intake and the final session. Patients who began the intervention with a poor alliance but ended with a good alliance (linear growth therapeutic alliance group) significantly decreased their use of maladaptive defenses over the course of therapy, while patients in the high and low alliance groups did not. Results showed that at the end of the intervention, MDS and alliance were related across all patients. This relation concerned particularly the linear growth therapeutic alliance profile. These results suggest that the developing therapeutic alliance might reflect the collaborative work between the patient and the therapist as they try to understand the causes of the crisis. This understanding might help reduce maladaptive defenses that were initially activated to ward off anxiety and distress.
Resumo:
Animal societies vary in the number of breeders per group, which affects many socially and ecologically relevant traits. In several social insect species, including our study species Formica selysi, the presence of either one or multiple reproducing females per colony is generally associated with differences in a suite of traits such as the body size of individuals. However, the proximate mechanisms and ontogenetic processes generating such differences between social structures are poorly known. Here, we cross-fostered eggs originating from single-queen (= monogynous) or multiple-queen (= polygynous) colonies into experimental groups of workers from each social structure to investigate whether differences in offspring survival, development time and body size are shaped by the genotype and/or prefoster maternal effects present in the eggs, or by the social origin of the rearing workers. Eggs produced by polygynous queens were more likely to survive to adulthood than eggs from monogynous queens, regardless of the social origin of the rearing workers. However, brood from monogynous queens grew faster than brood from polygynous queens. The social origin of the rearing workers influenced the probability of brood survival, with workers from monogynous colonies rearing more brood to adulthood than workers from polygynous colonies. The social origin of eggs or rearing workers had no significant effect on the head size of the resulting workers in our standardized laboratory conditions. Overall, the social backgrounds of the parents and of the rearing workers appear to shape distinct survival and developmental traits of ant brood.
The pharmacy of the future : Interdisciplinary collaboration and development of specialized services
Resumo:
RESUME Cette thèse se situe à la frontière de la recherche en économie du développement et du commerce international et vise à intégrer les apports de l'économie géographique. Le premier chapitre s'intéresse aux effets de création et de détournement de commerce au sein des accords régionaux entre pays en développement et combine une approche gravitaire et une estimation non paramétrique des effets de commerce. Cette analyse confirme un effet de commerce non monotone pour six accords régionaux couvrant l'Afrique, l'Amérique Latine et l'Asie (AFTA, CAN, CACM, CEDEAO, MERCO SUR et SADC) sur la période 1960-1996. Les accords signés dans les années 90 (AFTA, CAN, MERCOSUR et SADC) semblent avoir induis une amélioration du bien-être de leurs membres mais avec un impact variable sur le reste du monde, tandis que les accords plus anciens (CEDEAO et CACM) semblent montrer que les effets de commerce et de bien-être se réduisent pour finir par s'annuler à mesure que le nombre d'années de participation des Etats membres augmente. Le deuxième chapitre pose la question de l'impact de la géographie sur les échanges Sud-Sud. Ce chapitre innove par rapport aux méthodes classiques d'estimation en dérivant une équation de commerce à partir de l'hypothèse d'Armington et en intégrant une fonction de coût de transport qui prend en compte la spécificité des pays de l'UEMOA. Les estimations donnent des effets convaincants quant au rôle de l'enclavement et des infrastructures: deux pays enclavés de l'UEMOA commercent 92% moins que deux autres pays quelconques, tandis que traverser un pays de transit au sein de l'espace UEMOA augmente de 6% les coûts de transport, et que bitumer toutes les routes inter-Etat de l'Union induirait trois fois plus de commerce intra-UEMOA. Le chapitre 3 s'intéresse à la persistance des différences de développement au sein des accords régionaux entre pays en développement. Il montre que la géographie différenciée des pays du Sud membres d'un accord induit un impact asymétrique de celui-ci sur ses membres. Il s'agit d'un modèle stylisé de trois pays dont deux ayant conclu un accord régional. Les résultats obtenus par simulation montrent qu'une meilleure dotation en infrastructure d'un membre de l'accord régional lui permet d'attirer une plus grande part industrielle à mesure que les coûts de transport au sein de l'accord régional sont baissés, ce qui conduit à un développement inégal entre les membres. Si les niveaux d'infrastructure domestique de transport sont harmonisés au sein des pays membres de l'accord d'intégration, leurs parts industrielles peuvent converger au détriment des pays restés hors de l'union. Le chapitre 4 s'intéresse à des questions d'économie urbaine en étudiant comment l'interaction entre rendements croissants et coûts de transport détermine la localisation des activités et des travailleurs au sein d'un pays ou d'une région. Le modèle développé reproduit un fait stylisé observé à l'intérieur des centres métropolitains des USA: sur une période longue (1850-1990), on observe une spécialisation croissante des centres urbains et de leurs périphéries associée à une évolution croissante puis décroissante de la population des centres urbains par rapport à leurs périphéries. Ce résultat peut se transférer dans un contexte en développement avec une zone centrale et une zone périphérique: à mesure que l'accessibilité des régions s'améliore, ces régions se spécialiseront et la région principale, d'abord plus importante (en termes de nombre de travailleurs) va finir par se réduire à une taille identique à celle de la région périphérique.