Assigning and combining probabilities in single-case studies

There is currently a considerable diversity of quantitative measures available for summarizing the results in single-case studies. Given that the interpretation of some of them is difficult due to the lack of established benchmarks, the current paper proposes an approach for obtaining further numerical evidence on the importance of the results, complementing the substantive criteria, visual analysis, and primary summary measures. This additional evidence consists of obtaining the statistical significance of the outcome when referred to the corresponding sampling distribution. This sampling distribution is formed by the values of the outcomes (expressed as data nonoverlap, R-squared, etc.) in case the intervention is ineffective. The approach proposed here is intended to offer the outcome"s probability of being as extreme when there is no treatment effect without the need for some assumptions that cannot be checked with guarantees. Following this approach, researchers would compare their outcomes to reference values rather than constructing the sampling distributions themselves. The integration of single-case studies is problematic, when different metrics are used across primary studies and not all raw data are available. Via the approach for assigning p values it is possible to combine the results of similar studies regardless of the primary effect size indicator. The alternatives for combining probabilities are discussed in the context of single-case studies pointing out two potentially useful methods one based on a weighted average and the other on the binomial test.

Understanding expertise in teaching : case studies of second language teachers.

Se analiza desde el punto de vista crítico una amplia literatura sobre la cognición docente, para mostrar cómo las teorías de los profesores, sus conocimientos, su experiencia y sus objetivos determinan su práctica docente y su aptitud ante ella, tanto en el profesor principiante como en el experto. A partir de casos prácticos estudiados en las aulas se clarifica en qué consiste la pericia en la enseñanza de la lengua y cuales son los factores que determinan e influyen en su desarrollo y cómo los profesores de lengua la utilizan para la docencia.

The energy cycle and structural evolution of cyclones over southeastern South America in three case studies

In this paper, the Lorenz energy cycle over a limited area was applied for three cyclones with different origins and evolutions, where each of them was formed in an important cyclogenetic region near southeastern South America. The synoptic conditions and energetics were analyzed during each system`s life cycle and showed important relationships between their energy cycle and the evolution of their vertical structure. In the case of the weak baroclinic cyclone which formed on Brazil`s south-southeastern coast, the analysis showed that it originated through a midlevel cutoff low with contribution from barotropic instability. Its evolution would indicate potential transition to a hybrid system if the convective activity were stronger. The system that occurred in the La Plata River mouth had features of an oceanic bomb-type cyclogenesis and showed an important contribution from the available potential energy generation term through the latent heat release by the convection. Meanwhile, the system of the southern Argentina coast presented a classical baroclinic development of extratropical cyclogenesis in the energy cycle, from the wave amplification up to the final occlusion of the associated frontal system. These analyses revealed that the development of some cyclones that occur in eastern South America can present different mechanisms that are not related to the classical extratropical cyclogenesis.

Restructuring in manufacturing: case studies in Chile, Mexico and Venezuela

Includes bibliography

Restructuring in manufacturing: case studies of Chile, Mexico and Venezuela

Includes bibliography

Evolutionary stages of environmental management in computer companies located in Brazil: case studies

This study aims at identifying which environmental management practices computer companies located in Brazil are adopting, and classifying these companies according to the evolutionary stages of environmental management. For such, the case study research method was used at three companies. Results show that environmental management in the sector is geared towards compliance with laws and eco-efficiency, aimed at cutting costs. It was concluded that classification does not occur in a linear manner with defined borders, and that the multinational companies located in Brazil are greatly influenced by their foreign head offices, which are at more advanced evolutionary stages.

Identification of success and failure factors for technology transfer in biotechnology: case studies and surveys from Academic Sinica in Taiwan

Academia Sinica is the leading research institute in Taiwan founded in 1928. Its Office of Technology Transfer (OTT) was established in 1998. It made great efforts to dramatically turn around the technology transfer activity of Academia Sinica, especially in biotechnology. Academia Sinica has more than 80 cases of experience in biotechnology transfer with companies in Taiwanese industry in the past five years. The purpose of this study is to identify potential success and failure factors for biotechnology transfer in Taiwan. Eight cases were studied through in-depth interview. The results of the analysis were used to design two surveys to further investigate 81 cases (48 successful and 33 failure cases) of biotechnology transfer in Academia Sinica from 1999–2003. The results indicated that 10 of the 14 success factors were cited in more than 40% of the cases as contributing to the success of technology transfer. By contrast, only 5 out of 16 key factors were present in more than 30% of the failure cases.

Emerging Structures of Farmer Cooperatives in Vietnam: Case studies from the Mekong Delta

Four farmer groups for mango production and marketing were formed in 2002 in southern Vietnam in response to government support for the creation of market oriented farmer cooperatives. The role and structure of these groups is considered in terms of the degree to which they conform to internationally recognised principles for cooperative formation. Each of the farmer groups studied has evolved in different ways and their degree of compliance with the principles of cooperation varies widely. It is evident that state intervention and market forces may give rise to cooperative structures that differ from that intended under the principles surrounding cooperative law.

Delayed presentation of blunt duodenal injuries in children. Case report and review of literature

Background. Duodenal injuries are rare in children and classically present following a fall over the handle bar. Retroperitoneal location of the duodenum may lead to delay in diagnosis, and missed injuries are associated with increased morbidity and mortality. Case report. A 5-year-old child was admitted to the National Trauma Center, in Tirana (Albania), 28 hours after a Motor Vehicle Crash (MVC), complaining of mild abdominal pain. He was febrile (39°C) and had a white blood cells count of 18,000 mm3. On physical exam he had mild tenderness. Plain abdominal X-rays and Focused Abdominal Sonography for Trauma (FAST) were negative for free air or free fluid. The CT scan of the abdomen demonstrated free air and fluid in the retroperitoneal space. At laparatomy, a perforation of the second portion of the duodenum was found. A single layer suture repair of the duodenum with wide drainage was performed. The patient was discharged from the hospital tolerating oral feeding 8 days later. Conclusion. Duodenal injuries in children are rare. Most duodenal hematomas are managed non-operatively. This is a case of MCV with delayed presentation that was treated surgically for perforation successfully.

Genes involved in the metabolism of fatty acids and risk for Crohn's disease in children: a candidate gene study

Contexte - La prévalence de la maladie de Crohn (MC), une maladie inflammatoire chronique du tube digestif, chez les enfants canadiens se situe parmi les plus élevées au monde. Les interactions entre les réponses immunes innées et acquises aux microbes de l'hôte pourraient être à la base de la transition de l’inflammation physiologique à une inflammation pathologique. Le leucotriène B4 (LTB4) est un modulateur clé de l'inflammation et a été associé à la MC. Nous avons postulé que les principaux gènes impliqués dans la voie métabolique du LTB4 pourrait conférer une susceptibilité accrue à l'apparition précoce de la MC. Dans cette étude, nous avons exploré les associations potentielles entre les variantes de l'ADN des gènes ALOX5 et CYP4F2 et la survenue précoce de la MC. Nous avons également examiné si les gènes sélectionnés montraient des effets parent-d'origine, influençaient les phénotypes cliniques de la MC et s'il existait des interactions gène-gène qui modifieraient la susceptibilité à développer la MC chez l’enfant. Méthodes – Dans le cadre d’une étude de cas-parents et de cas-témoins, des cas confirmés, leurs parents et des contrôles ont été recrutés à partir de trois cliniques de gastro-entérologie à travers le Canada. Les associations entre les polymorphismes de remplacement d'un nucléotide simple (SNP) dans les gènes CYP4F2 et ALOX5 ont été examinées. Les associations allélique et génotypiques ont été examinées à partir d’une analyse du génotype conditionnel à la parenté (CPG) pour le résultats cas-parents et à l’aide de table de contingence et de régression logistique pour les données de cas-contrôles. Les interactions gène-gène ont été explorées à l'aide de méthodes de réduction multi-factorielles de dimensionnalité (MDR). Résultats – L’étude de cas-parents a été menée sur 160 trios. L’analyse CPG pour 14 tag-SNP (10 dans la CYP4F2 et 4 dans le gène ALOX5) a révélé la présence d’associations alléliques ou génotypique significatives entre 3 tag-SNP dans le gène CYP4F2 (rs1272, p = 0,04, rs3093158, p = 0.00003, et rs3093145, p = 0,02). Aucune association avec les SNPs de ALOX5 n’a pu être démontrée. L’analyse de l’haplotype de CYP4F2 a montré d'importantes associations avec la MC (test omnibus p = 0,035). Deux haplotypes (GAGTTCGTAA, p = 0,05; GGCCTCGTCG, p = 0,001) montraient des signes d'association avec la MC. Aucun effet parent-d'origine n’a été observé. Les tentatives de réplication pour trois SNPs du gene CYP4F2 dans l'étude cas-témoins comportant 225 cas de MC et 330 contrôles suggèrent l’association dans un de ceux-ci (rs3093158, valeur non-corrigée de p du test unilatéral = 0,03 ; valeur corrigée de p = 0.09). La combinaison des ces deux études a révélé des interactions significatives entre les gènes CYP4F2, ALOX et NOD2. Nous n’avons pu mettre en évidence aucune interaction gène-sexe, de même qu’aucun gène associé aux phénotypes cliniques de la MC n’a pu être identifié. Conclusions - Notre étude suggère que la CYP4F2, un membre clé de la voie métabolique LTB4 est un gène candidat potentiel pour MC. Nous avons également pu mettre en évidence que les interactions entre les gènes de l'immunité adaptative (CYP4F2 et ALOX5) et les gènes de l'immunité innée (NOD2) modifient les risques de MC chez les enfants. D'autres études sur des cohortes plus importantes sont nécessaires pour confirmer ces conclusions.