987 resultados para Developmental perspective


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Norms for a battery of instruments, including Denckla's and Garfield's tests of Motor Persistence, Benton's Right-Left Discrimination, two recall modalities (Immediate and Delayed) of the Bender Test, Wechsler's Digit Span, the Color Span Test and the Human Figure Drawing Test, were developed for the neuropsychological assessment of children in the greater Rio de Janeiro area. Additionally, the behavior of each child was assessed with the Composite Teacher Rating Scale (Brito GNO and Pinto RCA (1991) Journal of Clinical and Experimental Neuropsychology, 13: 417-418). A total of 398 children (199 boys and 199 girls balanced for age) with a mean age of 9.3 years (SD = 2.8), who were attending a public school in Niterói, were the subjects of this study. Gender and age had significant effects on performance which depended on the instrument. Nonachievers performed worse than achievers in most neuropsychological tests. Comparison of our data to the available counterparts in the United States revealed that American children outperformed Brazilian children on the Right-Left Discrimination, Forward Digit Span, Color Span and Human Figure Drawing Tests. Further analysis showed that the neurobehavioral data consist of different factorial dimensions, including Human Body Representation, Motor Persistence of the Legs, Orbito-Orobuccal Motor Persistence, Attention-Memory, Visuospatial Memory, Neuropsychomotor Speed, Hyperactivity-Inattention, and Anxiety-Negative Socialization. We conclude that gender and age should be taken into account when using the normative data for most of the instruments studied in the present report. Furthermore, we stress the need for major changes in the Brazilian public school system in order to foster the development of secondary cognitive abilities in our children

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Genetic and environmental factors have been implicated in the development of Alzheimer's disease (AD), the most common form of dementia in the elderly. Mutations in 3 genes mapped on chromosomes 21, 14 and 1 are related to the rare early onset forms of AD while the e4 allele of the apolipoprotein E (APOE) gene (on chromosome 19) is the major susceptibility locus for the most common late onset AD (LOAD). Serotonin (5-hydroxytryptamine or 5-HT) is a key neurotransmitter implicated in the control of mood, sleep, appetite and a variety of traits and behaviors. Recently, a polymorphism in the transcriptional control region upstream of the 5-HT transporter (5-HTT) gene has been studied in several psychiatric diseases and personality traits. It has been demonstrated that the short variant(s) of this 5-HTT gene-linked polymorphic region (5-HTTLPR) is associated with a different transcriptional efficiency of the 5-HTT gene promoter resulting in decreased 5-HTT expression and 5-HT uptake in lymphocytes. An increased frequency of this 5-HTTLPR short variant polymorphism in LOAD was recently reported. In addition, another common polymorphic variation in the 5-HT2A and 5-HT2C serotonin receptor genes previously analyzed in schizophrenic patients was associated with auditory and visual hallucinations in AD. These observations suggest that the involvement of the serotonin pathway might provide an explanation for some aspects of the affective symptoms commonly observed in AD patients. In summary, research on genetic polymorphisms related to AD and involved in receptors, transporter proteins and the enzymatic machinery of serotonin might enhance our understanding of this devastating neurodegenerative disorder.

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At the present time, protein folding is an extremely active field of research including aspects of biology, chemistry, biochemistry, computer science and physics. The fundamental principles have practical applications in the exploitation of the advances in genome research, in the understanding of different pathologies and in the design of novel proteins with special functions. Although the detailed mechanisms of folding are not completely known, significant advances have been made in the understanding of this complex process through both experimental and theoretical approaches. In this review, the evolution of concepts from Anfinsen's postulate to the "new view" emphasizing the concept of the energy landscape of folding is presented. The main rules of protein folding have been established from in vitro experiments. It has been long accepted that the in vitro refolding process is a good model for understanding the mechanisms by which a nascent polypeptide chain reaches its native conformation in the cellular environment. Indeed, many denatured proteins, even those whose disulfide bridges have been disrupted, are able to refold spontaneously. Although this assumption was challenged by the discovery of molecular chaperones, from the amount of both structural and functional information now available, it has been clearly established that the main rules of protein folding deduced from in vitro experiments are also valid in the cellular environment. This modern view of protein folding permits a better understanding of the aggregation processes that play a role in several pathologies, including those induced by prions and Alzheimer's disease. Drug design and de novo protein design with the aim of creating proteins with novel functions by application of protein folding rules are making significant progress and offer perspectives for practical applications in the development of pharmaceuticals and medical diagnostics.

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Norms for the Gardner Steadiness Test and the Purdue Pegboard were developed for the neuropsychological assessment of children in the metropolitan area of Rio de Janeiro. A computer-generated unbiased sample of 346 children with a mean age of 9.4 years (SD = 2.76), who were attending a large normal public school in this urban area, was the subject of this study. Two boys were removed from the study, one for refusing to participate and the other due to severe strabismus. Therefore, the final sample contained 344 children (173 boys and 171 girls). Sex and age of the child and hand preferred for writing, but not ethnic membership or social class, had significant effects on performance in the Gardner Steadiness Test and the Purdue Pegboard. Girls outperformed boys. Older children performed better than younger children. However, the predictive relationship between age of the child and neuropsychological performance included linear and curvilinear components. Comparison of the present results to data gathered in the United States revealed that the performance of this group of Brazilian children is equivalent to that of US children after Bonferroni's correction of the alpha level of significance. It is concluded that sex and age of the child and hand preferred for writing should be taken into account when using the normative data for the two instruments evaluated in the present study. Furthermore, the relevance of neurobehavioral antidotes for the obliteration of some of the probable neuropsychological effects of cultural deprivation in Brazilian public school children is hypothesized.

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This article proposes a comprehensive view of the origin of the mammalian brain. We discuss i) from which region in the brain of a reptilian-like ancestor did the isocortex originate, and ii) the origin of the multilayered structure of the isocortex from a simple-layered structure like that observed in the cortex of present-day reptiles. Regarding question i there have been two alternative hypotheses, one suggesting that most or all the isocortex originated from the dorsal pallium, and the other suggesting that part of the isocortex originated from a ventral pallial component. The latter implies that a massive tangential migration of cells from the ventral pallium to the dorsal pallium takes place in isocortical development, something that has not been shown. Question ii refers to the origin of the six-layered isocortex from a primitive three-layered cortex. It is argued that the superficial isocortical layers can be considered to be an evolutionary acquisition of the mammalian brain, since no equivalent structures can be found in the reptilian brain. Furthermore, a characteristic of the isocortex is that it develops according to an inside-out neurogenetic gradient, in which late-produced cells migrate past layers of early-produced cells. It is proposed that the inside-out neurogenetic gradient was partly achieved by the activation of a signaling pathway associated with the Cdk5 kinase and its activator p35, while an extracellular protein called reelin (secreted in the marginal zone during development) may have prevented migrating cells from penetrating into the developing marginal zone (future layer I).

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The objective of the present study was to examine the effect of green tea polyphenols (GTPs) supplementation during in vitro maturation, in vitro fertilization, and in vitro culture on the developmental competence of bovine oocytes. Cumulus-oocyte complexes aspirated from the ovaries were matured in vitro (38.5ºC for 24 h) and fertilized (38.5ºC for 15-18 h) and embryos were cultured (38.5ºC for 192 h) in a defined conditioned medium with or without GTPs supplementation. The GTPs used in the present study contained 99% catechin derivatives, with the major components being 50% (-)-epigallocatechin gallate, 22% (-)-epicatechin gallate, 18% (-)-epigallocatechin, and 10% (-)-epicatechin. Four replicate trials were done for each type of experiment. GTPs supplementation (15 µM) of the maturation medium led to a significant increase in the rate of blastocyst formation (34.0 vs 21.4%, P < 0.05). However, the rate of blastocyst formation was not improved when higher GTPs concentrations (20 or 25 µM) were added to the in vitro maturation medium. During in vitro fertilization, supplementation with higher GTPs concentrations (20 or 25 µM) significantly reduced the rate of blastocyst formation (P < 0.05). Supplementation of the culture medium with 15 µM GTPs improved the rate of blastocyst formation, while higher GTPs concentrations (25 µM) significantly reduced embryo development (P < 0.05). In conclusion, these results demonstrate that supplementation with GTPs at low concentration (15 µM) during in vitro maturation and in vitro culture improved the developmental competence of bovine oocytes.

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Tämän tutkimuksen tarkoituksena on havainnoida keskittämisen ja hajauttamisen hyötyjä ja haittoja logistiikassa, ja selventää mitä tekijöidä tulee huomioida näiden kahden rakenteen väliltä valitessa. Tutkimus kokoaa molempien rakenteiden hyödyt ja haitat hyödyntämällä sekä haastateltujen työntekijöiden osaamista ja mielipiteitä että aiheeseen liittyvää kirjallisuutta. Päätavoitteena on lisätä ymmärrystä siitä, miten organisaatiorakenne vaikuttaa logistiseen toimintaan.

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Panic disorder patients are vulnerable to recurrent panic attacks. Two neurochemical hypotheses have been proposed to explain this susceptibility. The first assumes that panic patients have deficient serotonergic inhibition of neurons localized in the dorsal periaqueductal gray matter of the midbrain that organize defensive reactions to cope with proximal threats and of sympathomotor control areas of the rostral ventrolateral medulla that generate most of the neurovegetative symptoms of the panic attack. The second suggests that endogenous opioids buffer normal subjects from the behavioral and physiological manifestations of the panic attack, and their deficit brings about heightened suffocation sensitivity and separation anxiety in panic patients, making them more vulnerable to panic attacks. Experimental results obtained in rats performing one-way escape in the elevated T-maze, an animal model of panic, indicate that the inhibitory action of serotonin on defense is connected with activation of endogenous opioids in the periaqueductal gray. This allows reconciliation of the serotonergic and opioidergic hypotheses of panic pathophysiology, the periaqueductal gray being the fulcrum of serotonin-opioid interaction.

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An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.

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On-going process of globalization makes companies all over the world to go beyond the national markets and internationalize. Organizational form of multinational corporation (MNC) has capabilities for establishing the affiliate companies in several countries. Thus, the relocation of resources occurs and particularly, the cross-border transfer of knowledge which possesses the competitive advantage. However, differences in countries` business environments and cultures may constrain this capability. The research aim of this thesis is to investigate the role of subsidiary’s network competence (ability to build and manage the relationships with other local business units) and international business competence in relation to the benefits that MNC receives from a subsidiary. Additionally, subsidiary’s business adaptation, partnerships and knowledge transfer mechanism with parent company and external partners are investigated. This research, conducted in the Finnish-Russian context, consists of theoretical and empirical parts. The qualitative approach in the form of multiple case studies is employed. The empirical data incorporated primary and secondary data in the form of interviews collected in 2013 and 2015 years. Interviews were collected from four Finnish case companies in Saint-Petersburg and Kaluga region and five Russian partner companies. Results are drawn from two cases from Saint-Petersburg. The abductive research approach for the results analysis is adopted. The results indicate that both competencies lead to the subsidiary’s local embeddedness in the form of mutual business activities with local business partners and product adaptation for the local market needs. In addition to the monetary benefits in form of payments or turnover share, local embeddedness brings the knowledge of the local environment which is utilized by an MNC in the long-term planning. Another found tacit benefit is the access to the national market. This is strategically useful benefit not only for parent MNC but also for the subsidiary’s partners, i.e. international suppliers.

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The purpose of this qualitative research is to analyze western-based companies’ social media usage in internationalization into China and to identify social media presence’ impact on the internationalization process. Additionally, the benefits and challenges a western company may face while using social media in China will be illustrated. Competitive advantages, knowledge, networks and relations, and costs and risks could be identified as the key antecedents for successful internationalization. A great social media presence could create a competitive advantage for a western company while competitive advantages may be communicated in social media marketing, knowledge and networks can be enhanced and utilized in internationalization via social media two-way communication. The biggest benefit for internationalization resulted from decreased marketing costs due to cost-effectiveness of social media. The results revealed that cost effective brand awareness was the main benefit from the social media usage in internationalization into China. However, companies struggled with the limited resources and despite of understanding the importance of Chinese social media, lacked sufficient resources for the social media operations. Companies should determine clear strategy and goals that they are willing to achieve via social media in internationalization process, and allocate required resources according to the social media strategy. Localization of the social media operations is important in China, and business-to-consumer companies tend to benefit more from the social media presence. Business-to-business companies may increase the brand’s credibility by successful Chinese social media operations.

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Modern food systems face complex global challenges such as climate change, resource scarcities, population growth, concentration and globalization. It is not possible to forecast how all these challenges will affect food systems, but futures research methods provide possibilities to enable better understanding of possible futures and that way increases futures awareness. In this thesis, the two-round online Delphi method was utilized to research experts’ opinions about the present and the future resilience of the Finnish food system up to 2050. The first round questionnaire was constructed based on the resilience indicators developed for agroecosystems. Sub-systems in the study were primary production (main focus), food industry, retail and consumption. Based on the results from the first round, the future images were constructed for primary production and food industry sub-sections. The second round asked experts’ opinion about the future images’ probability and desirability. In addition, panarchy scenarios were constructed by using the adaptive cycle and panarchy frameworks. Furthermore, a new approach to general resilience indicators was developed combining “categories” of the social ecological systems (structure, behaviors and governance) and general resilience parameters (tightness of feedbacks, modularity, diversity, the amount of change a system can withstand, capacity of learning and self- organizing behavior). The results indicate that there are strengths in the Finnish food system for building resilience. According to experts organic farms and larger farms are perceived as socially self-organized, which can promote innovations and new experimentations for adaptation to changing circumstances. In addition, organic farms are currently seen as the most ecologically self-regulated farms. There are also weaknesses in the Finnish food system restricting resilience building. It is important to reach optimal redundancy, in which efficiency and resilience are in balance. In the whole food system, retail sector will probably face the most dramatic changes in the future, especially, when panarchy scenarios and the future images are reflected. The profitability of farms is and will be a critical cornerstone of the overall resilience in primary production. All in all, the food system experts have very positive views concerning the resilience development of the Finnish food system in the future. Sometimes small and local is beautiful, sometimes large and international is more resilient. However, when probabilities and desirability of the future images were questioned, there were significant deviations. It appears that experts do not always believe desirable futures to materialize.

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Med avstamp i ett satsbegrepp som inspirerats av Ludwig Wittgenstein, där sats och kontext betraktas som internt förbundna och där den verkliga användningen av en sats är central för dess mening, visar avhandlingen hur filosofers olika uppfattning om den filosofiska terminologins roll och möjligheter har följder för deras sätt att uppfatta och behandla filosofiska frågeställningar. Moores paradox fungerar som testfall. Denna kända filosofiska frågeställning har diskuterats sedan 1940-talet och kretsar kring hävdandet av satsen ”Jag tror att det regnar och det regnar inte”. Problemet är att det vore märkligt för en talare att hävda satsen om sig själv: det verkar finnas ett logiskt hinder för att hävda en sats även om den är välformad, kunde vara sann och inte på ett entydigt sätt innehåller en kontradiktion. Moores paradox behandlas genom att granska några lösningsförslag (framförda av bl.a. G.E. Moore, J. L. Austin, J. Searle) och de uppfattningar om språket som de förutsätter. Genom att kontrastera dessa med ett användarperspektiv där språkets användning i meningsfulla sammanhang förväntas spela en central roll i behandlingen av paradoxen visar författaren hur också den intellektuella kontext inom vilken en filosof betraktar paradoxen spelar en avgörande roll för vilka mått som krävs för att upplösa den. Istället för att föreslå en egen lösning presenteras en behandling av paradoxen genom en diskussion och utredning av de grundvillkor som leder till att den uppstår. Här intar satsbegreppet en central plats. Avhandlingen är författad inom traditionen efter den senare Wittgenstein (närmare bestämt den gren som ansluter sig till en s.k. terapeutisk filosofisyn) men går i dialog med filosofiskt arbete som ligger utanför traditionen. Författaren strävar både till att medla mellan, sammanföra och särskilja olika temata som behandlats på ett sätt inom traditionen och på andra sätt utanför den och använder sig här av metaforen att filosofera inifrån i kontrast till utanför språket. Avhandlingens huvudsakliga bidrag är till metafilosofin genom dess fokus på filosofins metod. ------------------------------------------------------------ Mooren paradoksi on tunnettu filosofinen ongelma, josta on keskusteltu 1940-luvulta alkaen. Paradoksin keskeisenä osana esiintyy väitelause ”Uskon, että ulkona sataa, mutta ulkona ei sada”. Ongelman lähtökohta on, että olisi merkillistä jos puhuja esittäisi lauseen itseään koskevana väitteenä: väite näyttää olevan loogisesti mahdoton esittää, vaikka se on hyvinmuodostettu, mahdollisesti tosi, eikä yksiselitteisellä tavalla sisällä kontradiktiota. Tässä väitöskirjassa Mooren paradoksi esiintyy esimerkkinä filosofisesta ongelmasta, jossa mm. lausekäsitteellä on keskeinen rooli ja jonka avulla voidaan muodostella ns. kielensisäinen filosofinen näkökulma. Mooren paradoksia käsitellään tarkastelemalla muutamia ratkaisuehdotuksia (mm. G.E. Mooren, J.L. Austinin, J. Searlen esittämät) ja niitä kielikäsityksiä joita nämä ratkaisuehdotukset edellyttävät. Asettamalla vastakkain ratkaisuehdotukset ja käyttäjänäkymä, jossa kielenkäyttö mielekkäissä konteksteissa asetetaan keskeiseen asemaan paradoksin käsittelyssä, kirjoittaja osoittaa miten myös paradoksin filosofisen tarkastelun intellektuaalinen konteksti on hyväksyttävien toimenpiteiden löytämisen kannalta ratkaisevaa. Uuden ratkaisun sijaan kirjoittaja ehdottaa paradoksin terapeuttista käsittelyä: keskustelua ja selontekoa niistä perusehdoista, jotka johtavat sen syntyyn. Tässä käsittelyssä lausekäsite on keskipisteenä – erityisesti Ludwig Wittgensteinin inspiroima lausekäsitys, jossa lauseen mielekkyyden kannalta sen todellinen käyttö mielekkäässä kontekstissa on ratkaiseva tekijä. Väitöskirja liittyy myöhäisiwittgensteinilaiseen perinteeseen, johon kuuluu ns. terapeuttinen filosofiankäsitys, mutta teos keskustelee myös tradition ulkopuolisten ajattelijoiden kanssa yrittäen yhdistää, sovitella ja myös eritellä teemoja, joita käsitellään yhdellä tavalla tradition sisällä ja toisella tavalla sen ulkopuolella. Väitöskirjan pääasiallinen panos sijoittuu metafilosofiaan, koska sen mielenkiinnon kohteena ovat erityisesti filosofian menetelmät.

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Many internationally adopted children have lived their first years of life in an environment with limited opportunities for primary caregiving. The lack of consistent care increases the prevalence of attachment disorders among them. Less is known about the influences of attachment disorders on a child’s later course of life. This study is part of the Finnish Adoption Study. Parents of all Finnish children who had been internationally adopted by legal adoption organisations between 1985 and 2007 were sent questionnaires (N=1450). Parental evaluations of the children’s symptoms of reactive attachment disorder (RAD) at the time of adoption, their later learning or language problems using a screening scale, and children’s self-reported school bullying experiences were evaluated. Each child’s attachment-related behavioural problems were requested in a follow-up survey 1.9 and 3.8 years after adoption and compared with a Finnish reference group. This study indicated that Finnish internationally adopted children have at least three-fold prevalence of learning and language problems compared with their age-mates. A child’s symptoms of attachment disorders were associated with learning or language problems at school age as well as with his/her school bullying experiences. The adopted children had more attachment-related behavioural problems two years after adoption than their age-mates, but the difference was no longer evident four years after adoption. In conclusion, this study showed that the symptoms of attachment disorder indicate a risk for an adopted child’s later developmental outcome. The findings demonstrate the need for comprehensive clinical examinations and planning of treatment strategies for children with symptoms of RAD.