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Dieser Artikel möchte für die wachsende Bedeutung von systematischen Übersichtsarbeiten in den Human- und Sozialwissenschaften und die diversen Möglichkeiten der Unterstützung solcher Studien von bibliothekarischer Seite sensibilisieren. Er schildert die Entwicklung systematischer Übersichtsarbeiten in den letzten 10 Jahren, analysiert, welche Rollen dabei Fachreferent*innen bzw. Information Specialists zufallen können und gibt Empfehlungen, welchen konkreten Beitrag die Berufsgruppe der wissenschaftlichen Bibliothekar*innen für solche Forschungsprojekte leisten kann. This article aims to raise awareness of the growing importance of systematic reviews in the human and social sciences and the various ways in which libraries can support such studies. It describes the development of Systematic Reviews over the last 10 years, analyzes which roles can be played by subject librarians and information specialists and gives recommendations on the concrete contribution that the professional group of academic librarians can make to such research projects.

Objective: Bipolar disorder is characterized by aberrant neurophysiological responses as measured with electroencephalography (EEG) and magnetoencephalography (MEG), including the 40-Hz auditory steady-state response (ASSR). 40-Hz ASSR deficits are also found in patients with schizophrenia and may represent a transdiagnostic biomarker of neuronal circuit dysfunction. In this systematic review and meta-analysis, we summarize and evaluate the evidence for 40-Hz ASSR deficits in patients with bipolar disorder. Methods: We identified studies from PubMed, EMBASE, and SCOPUS. We assessed the risk of bias, calculated Hedges’ g meta-level effect sizes, and investigated small-study effects using funnel plots and Egger regression. Results: Seven studies, comprising 396 patients with bipolar disorder and 404 healthy controls, were included in the meta-analysis. Studies displayed methodological heterogeneity and an overall high risk of bias. Patients with bipolar disorder showed consistent reductions in 40-Hz ASSR evoked power (Hedges’ g = −0.49; 95% confidence intervals [−0.67, −0.31]) and inter-trial phase coherence (ITPC) (Hedges’ g = −0.43; 95 %CI [−0.58, −0.29]) compared with healthy controls. Conclusions: Our meta-analysis provides evidence that 40-Hz ASSRs are reduced in patients with bipolar disorder compared with healthy controls. Significance: Future large-scale studies are warranted to link 40-Hz ASSR deficits to clinical features and developmental trajectories.

In the last four decades, mental health services for people with Severe Mental Illness (SMI) have seen asylums replaced by a balanced model of Community Mental Healthcare (CMH). Innovative approaches and strategies in the field of CMH have been extensively researched. However, this research has been hampered by issues limiting their capacity to inform clinicians and policymakers. We conducted an overview of meta-analyses of the effectiveness of innovative CMH models focussing on clinical and psychosocial outcomes in comparisons with standard care in adults with SMI. Based on the 12 eligible studies, we appraised, synthesised and graded the resulting evidence. There was moderate quality evidence that case management, Early Intervention Services (EIS) and caregiver-directed interventions were superior to standard care in reducing hospital admission. In relation to psychosocial outcomes, EIS showed high quality evidence of a small effect on global functioning. There was moderate quality evidence for a similar effect of Intensive Case Management, and for a large effect of family intervention. For quality of life, both EIS and self-management education had a small effect, with moderate quality. The level of research about effective CMH models is therefore substantial. However, several gaps related to innovative CMH not yet covered in meta‐analytic synthesis, need to be filled.

National audience; Head and neck cancers comprise a variety of tumours depending on the sub-site, for which target volumes and the prescribed doses need to be individualized according to each patient's history and presentation. This article aims at describing the main factors involved in decision-making regarding dose and volume, as well as ongoing research. Contouring and treatment guidelines, use of altered fractionation, major prognostic factors, the role of Human papillomavirus and of functional imaging will be presented and discussed.

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Background: The present meta-analysis aims to conduct a systematic comparative study of the curative effects of Percutaneous Endoscopic Transforaminal Discectomy (PETD) and Percutaneous Endoscopic Interlaminar Discectomy (PEID) when used to treat Lumbar Disc Herniation (LDH). Methods: The following online databases will be searched to find articles related to treating of LDH using PETD and PEID, namely PubMed, EMBASE, Cochrane databases, China National Knowledge Infrastructure, WanFang Database, and Web of Science. The search will include all articles published from inception until August 2021. Articles will be included according to the inclusion criteria. Two authors will independently screen and assess the quality of each study. RevMan (version 5.3) will be adopted to complete data analysis and evaluate the statistical significance of each operating technique in various outcomes. Results: The present meta-analysis will evaluate the curative effects of using PETD and PEID to treat LDH patients. Conclusion: Compare the clinical efficiency of PETD and PEID as therapy for LDH with postoperative hypoesthesia, complications in surgical site wounds, nerve root injury, transfer to open surgery, recurrence, partial decompression, and other complications. The comparative analysis will help determine the difference between the 2 surgical methods of PETD and PEID for treating LDH. OSF registration number: August 2, 2021.osf.io/hr964. (https://osf.io/hr964/)

Vi setter sammen resultater fra flere studier i en syntetisk database og gjennomfører en såkalt meta-analyse for å gi et sammenfattende bilde av effekter av arbeidsmarkedstiltak rettet mot ungdom. I alt inngår 425 effektestimater fra 44 forskjellige forskningsarbeider fra Finland, Norge, Sverige, Danmark, Tyskland og Storbritannia i meta-analysen. Våre konklusjoner bekrefter at opplæringstiltak, lønnstilskudd og forsterket aktivering er forbundet med mer positive effektestimater enn arbeidspraksis og sysselsettingstiltak i offentlig sektor.

Background and Objective Major depressive disorder is a multidimensional disease, in which demonstrating the efficacy of treatments is difficult. The Hamilton Rating Scale for Depression (HRSD) and the Montgomery–Asberg Depression Rating Scale (MADRS) cover different domains but are used interchangeably as primary measures of the outcome in trials and—with standardized measures—in meta-analyses. We aimed at understanding (i) whether the choice of the outcome measurement tool can influence the outcome of a trial, and if so, (ii) whether one systematically outperforms the other, and (iii) whether using standardized measures of the effect in meta-analysis is justified. Methods Short-term randomized trials in patients with major depressive disorder that used both the scales were systematically searched and the results were collected. To quantify the differences in the results—both in terms of the standardized mean difference (SMD) and odds ratio (OR) for response—and their range, data were analyzed and plotted with the Bland–Altman method. Results 161 comparisons from 80 studies were included, involving a total of 18,189 patients. Neither of the two scales appears systematically more sensitive to the treatment effect than the other in terms of SMDs (P-value = 0.06, 95% CI −0.044 to 0.001) or ORs (P-value = 0.15, 95% CI −0.25 to 0.04). However, the variability of differences between the HRSD and MADRS largely depends on the number of patients included in the comparison. Conclusion No systematic differences between the two scales were found supporting the use of standardized measures in meta-analyses. However, the same trial may give very different results with either scale, especially in small trials. Further research is needed to understand the causes of this variability.

International audience; One of the most debated topics in pig production is the need to study, understand and change the production system in order to improve nutrient efficiency, becoming more environmentally friendly. The nitrogen excretion has highly deleterious effects on the environment, and it is necessary to develop tools that help to reduce the excretion of this compound without compromising productivity. Therefore, two models were generated to estimate the efficiency of weight gain in relation to excreted nitrogen in postweaning piglets. Data for testing these models were obtained from previous master and PhD studies carried out at the Federal University of Rio Grande do Sul, Animal Science Laboratory using piglets in the post-weaning phase with results for performance and digestibility. The database that was constructed was composed of raw data from 10 studies carried out between 2000 and 2016, on a total of 726 piglets weaned at ages between 17 and 28 days, and to which 62 different treatments were applied. An exploratory analysis of the data was done by evaluating scatter plots and histograms, and variables representing different treatments were used in a stepwise multiple linear regression analysis, with the F-test used as the selection criterion. Two models were generated that either considered the nitrogen retained or not, to estimate the ratio between weight gain and excreted nitrogen using generalized linear model procedure. The authors analyzed the behavior of each variable to evaluate whether the equation generated was biologically coherent. Weight gain, dry matter intake, nitrogen intake, metabolizable energy intake, retained nitrogen and urinary nitrogen were all significant (P

Study selection: Randomized controlled trials published after 2007 with (former) healthcare patients ≥ 21 years of age were included if physical activity was measured objectively using a wearable monitor for both feedback and outcome assessment. The main goal of included studies was promoting physical activity. Any concurrent strategies were related only to promoting physical activity. Data extraction: Effect sizes were calculated using a fixed-effects model with standardized mean difference. Information on study characteristics and interventions strategies were extracted from study descriptions. Data synthesis: Fourteen studies met the inclusion criteria (total n = 1,902), and 2 studies were excluded from meta-analysis. The overall effect size was in favour of the intervention groups (0.34, 95% CI 0.23–0.44, p

Las barreras del idioma pueden tener consecuencias negativas para la salud de los pacientes que no hablan inglés y pueden además traer aparejado un aumento de los costes para la salud pública. Una de las soluciones sería recurrir a los servicios de unos intérpretes profesionales. Sin embargo, el hecho de solicitar la participación de dichos profesionales sigue una práctica poco extendida y la razón que se da a menudo es la falta de recursos financieros. ¿Tiene el uso de un intérprete profesional un impacto positivo en la prestación de servicios de salud? ¿Qué tipos de costes supone tal recurso? Para arrojar luz sobre este tema, se llevó a cabo el meta-análisis de 35 estudios científicos realizados en los Estados Unidos que abordan estos temas. La conclusión más destacada es que la gestión médica del alófono se mejora de manera significativa y que los costes incurridos son mínimos en comparación con los beneficios obtenidos., Language barriers can have negative consequences for non-English speaking patients’ health and, what’s more, lead to an increase in costs for public health. One of the solutions would be to use professional interpreters. However, asking for the intervention of these professionals is not common practice yet and the reason often given is the lack of financial resources. Does the use of a professional interpreter positively impact the delivery of health care? What are the costs of such use? In order to shed light on this topic, we proceeded with a meta-analysis of 35 scientific studies conducted in the United States that address these issues. The main result is that the improvement in the medical management of the non-English speaking patient is noticeable and that the costs are minimal compared to the obtained benefits.

Cet article s’intéresse à l’influence du leadership scolaire sur l’efficacité de service public de l’établissement scolaire. Dans cette perspective, des méta-analyses stratifiées et une méta-analyse de régression sont réalisées à partir d’un ensemble de 28 études publiées entre 1993 et 2018. Ces méta-analyses mettent en exergue une forte hétérogénéité des résultats des études sélectionnées et montrent que le leadership scolaire n’a que peu d’effet empirique sur l’efficacité de service public de l’établissement scolaire. Elles soulignent cependant que les effets du leadership scolaire sont majorés dans les pays aux pouvoirs de décision majoritairement dévolus aux établissements scolaires., This article focuses on the influence of school leadership on the effectiveness of the public service provided by schools. In this context, stratified meta-analyses and a meta-regression analysis were carried out based on a series of 28 studies published between 1993 and 2018. The meta-analyses highlight significant heterogeneity of results among the selected studies. They also show that school leadership has little empirical effect on the effectiveness of the public service provided by schools. However, they make it clear that the effects of school leadership are greater in countries where decision-making powers are largely vested in schools., El presente artículo aborda la influencia del liderazgo escolar sobre la eficacia del servicio público del centro escolar. Se realizan metaanálisis estratificados y un metaanálisis de regresión sobre un conjunto de 28 estudios publicados entre 1993 y 2018. Estos metaanálisis revelan que los resultados de los estudios seleccionados son muy heterogéneos y muestran que el liderazgo escolar tiene muy pocos efectos empíricos sobre la eficacia del servicio público del centro escolar. Sin embargo también señalan que los efectos del liderazgo escolar se incrementan en aquellos países en los que el poder de decisión les incumbe predominantemente a los centros escolares.

L’objet de la présente contribution est de dresser un état des lieux de la recherche en management dans le contexte africain. Sur la base d’un ensemble de 221 publications répertoriées entre 2014 et 2018, nous faisons une méta-analyse qui débouche sur trois tendances fortes : la prééminence des problématiques de finance, de GRH et de marketing; une forte propension pour les études confirmatoires dans un contexte où les théories existantes peinent à décrire les réalités organisationnelles et enfin, une inégalité du volume des publications en fonction des espaces culturels. Ces constats amènent à soutenir que les perspectives méthodologiques de recherche sur le management en Afrique méritent d’être repensées, si l’on veut découvrir l’essence d’un management proprement africain., This paper aims to make a roundup of management researches in African context. From the set of recent publications (2014–2018) on the theme, we make a meta-analysis that leads to three main tendencies: the higher interest accorded to finance, Human management resources and marketing problematics; the wide proportion of confirmative studies in a context where available theories don’t describe organizational realities and the unequal volume of publications from one country to another. That situation is calling for a rethinking of some methodological aspects of research in view to access a management practices observed in the continent., El objeto de la presenta contribución es investigar la literatura en management en el contexto africano. Sobre la base de un conjunto de 221 publicaciones grabadas entre 2014 y 2018, efectuamos un meta-análisis que desemboca en tres tendencias fuertes : la preeminencia de las problemáticas de finanzas, de GRH ( gestión de los recursos humanos) y de marketing ; una fuerte propensión para estudios confirmatorios en un contexto del que las teorías existentes encuentran dificultades para describir las realidades organizacionales y, finalmente, una desigualdad del volumen de las publicaciones en función de los espacios culturales. Estas constataciones conducen a sostener que las perspectivas metodológicas de búsqueda sobre el management en África merecen estar pensadas de nuevosi queremos describir la esencia de un management propiamente africano

Background Bacterivores, mostly represented by protists and nematodes, are a key component of soil biodiversity involved in soil fertility and plant productivity. In the current context of global change and soil biodiversity erosion, it becomes urgent to suitably recognize and quantify their ecological importance in ecosystem functioning. Scope Using meta-analysis tools, we aimed at providing a quantitative synthesis of the ecological importance of soil bacterivores on ecosystem functions. We also intended to produce an overview of the ecological factors that are expected to drive the magnitude of bacterivore effects on ecosystem functions. Conclusions Bacterivores in soil contributed significantly to numerous key ecosystem functions. We propose a new theoretical framework based on ecological stoichiometry stressing the role of C:N:P ratios in soil, microbial and plant biomass as important parameters driving bacterivore-effects on soil N and P availability for plants, immobilization of N and P in the bacterial biomass, and plant responses in nutrition and growth.

On pig farms, a high proportion of the cost of production comes from feed costs. However, the use of alternative ingredients such as legume seeds may help to reduce this cost. In fact, legume seeds are an important source of essential amino acids (EAA) and can therefore be an alternative to oilseed meals. However, the accurate use of these legume seeds requires a precise knowledge of the standardized ileal digestibility (SID) of EAA, which may vary depending on its botanical variety. A meta-analysis was performed on a database compiling data from 41 studies published between 1981 and 2013 and 178 dietary treatments. Models of prediction of the SID of EAA as well as the dietary concentration of digestible standardized EAA (dEAA) were obtained, based on the chemical composition of ingredients reported in the publications. The effect of the type of legume seeds (faba bean, lupin, pea and soya bean), surgical procedures (T-cannula, re-entrant cannulas, post valve T-cannulas and ileo-rectal anastomosis), and BW of pigs (BW⩽25 kg BW>25 kg) were also tested in each model. Results showed that dietary CP and crude fibre (CF) were, respectively, the best predictors of each EAA SID for faba bean, lupin and pea (R 2=0.42 to 0.89) and soya bean (R 2=0.32 to 0.77). For the dEAA content, the best prediction models included dietary CP and ADF for faba bean, lupin and pea and soya bean, respectively, with R 2 ranging from 0.66 to 0.98. Models developed in this study allow predicting the digestibility of EAA in these alternatives feedstuffs.

Die Etablierung von Hochdurchsatz-Technologien zur Durchführung von Genexpressionsmessungen führte in den letzten 20 Jahren zu einer stetig wachsende Menge an verfügbaren Daten. Sie ermöglichen durch Kombination einzelner Experimente neue Vergleichsstudien zu kombinieren oder Experimente aus verschiedenen Studien zu großen Datensätzen zu vereinen. Dieses Vorgehen wird als Meta-Analyse bezeichnet und in dieser Arbeit verwendet, um einen großen Genexpressionsdatensatz aus öffentlich zugänglichen T-Zell Experimenten zu erstellen. T-Zellen sind Immunzellen, die eine Vielzahl von unterschiedlichen Funktionen des Immunsystems inititiieren und steuern. Sie können in verschiedene Subtypen mit unterschiedlichen Funktionen differenzieren. Der mittels Meta-Analyse erstellte Datensatz beinhaltet nur Experimente zu einem T-Zell-Subtyp, den regulatorischen T-Zellen (Treg) bzw. der beiden Untergruppen, natürliche Treg (nTreg) und induzierte Treg (iTreg) Zellen. Eine bisher unbeantwortete Frage lautet, welche subtyp-spezifischen gen-regulatorische Mechanismen die T-Zell Differenzierung steuern. Dazu werden in dieser Arbeit zwei spezifische Herausforderungen der Treg Forschung behandelt: (i) die Identifikation von Zelloberflächenmarkern zur Unterscheidung und Charakterisierung der Subtypen, sowie (ii) die Rekonstruktion von Treg-Zell-spezifischen gen-regulatorischen Netzwerken (GRN), die die Differenzierungsmechanismen beschreiben. Die implementierte Meta-Analyse kombiniert mehr als 150 Microarray-Experimente aus über 30 Studien in einem Datensatz. Dieser wird benutzt, um mittels Machine Learning Zell-spezifische Oberflächenmarker an Hand ihres Expressionsprofils zu identifizieren. Mit der in dieser Arbeit entwickelten Methode wurden 41 Genen extrahiert, von denen sechs Oberflächenmarker sind. Zusätzliche Validierungsexperimente zeigten, dass diese sechs Gene die Experimenten beider T-Zell Subtypen sicher unterscheiden können. Zur Rekonstruktion von GRNs vergleichen wir unter Verwendung des erstellten Datensatzes 11 verschiedene Algorithmen und evaluieren die Ergebnisse mit Informationen aus Interaktionsdatenbanken. Die Evaluierung zeigt, dass die derzeit verfügbaren Methoden nicht in der Lage sind den Wissensstand Treg-spezifischer, regulatorsicher Mechanismen zu erweitern. Abschließend präsentieren wir eine Datenintegrationstrategie zur Rekonstruktion von GRN am Beispiel von Th2 Zellen. Aus Hochdurchsatzexperimenten wird ein Th2-spezifisches GRN bestehend aus 100 Genen rekonstruiert. Während 89 dieser Gene im Kontext der Th2-Zelldifferenzierung bekannt sind, wurden 11 neue Kandidatengene ohne bisherige Assoziation zur Th2-Differenzierung ermittelt. Die Ergebnisse zeigen, dass Datenintegration prinzipiell die GRN Rekonstruktion ermöglicht. Mit der Verfügbarkeit von mehr Daten mit besserer Qualität ist zu erwarten, dass Methoden zur Rekonstruktion maßgeblich zum besseren Verstehen der zellulären Differenzierung im Immunsystem und darüber hinaus beitragen können und so letztlich die Ursachenforschung von Dysfunktionen und Krankheiten des Immunsystems ermöglichen werden., Within the last two decades high-throughput gene expression screening technologies have led to a rapid accumulation of experimental data. The amounts of information available have enabled researchers to contrast and combine multiple experiments by synthesis, one of such approaches is called meta-analysis. In this thesis, we build a large gene expression data set based on publicly available studies for further research on T cell subtype discrimination and the reconstruction of T cell specific gene regulatory events. T cells are immune cells which have the ability to differentiate into subtypes with distinct functions, initiating and contributing to a variety of immune processes. To date, an unsolved problem in understanding the immune system is how T cells obtain a specific subtype differentiation program, which relates to subtype-specific gene regulatory mechanisms. We present an assembled expression data set which describes a specific T cell subset, regulatory T (Treg) cells, which can be further categorized into natural Treg (nTreg) and induced Treg (iTreg) cells. In our analysis we have addressed specific challenges in regulatory T cell research: (i) discriminating between different Treg cell subtypes for characterization and functional analysis, and (ii) reconstructing T cell subtype specific gene regulatory mechanisms which determine the differences in subtype-specific roles for the immune system. Our meta-analysis strategy combines more than one hundred microarray experiments. This data set is applied to a machine learning based strategy of extracting surface protein markers to enable Treg cell subtype discrimination. We identified a set of 41 genes which distinguish between nTregs and iTregs based on gene expression profile only. Evaluation of six of these genes confirmed their discriminative power which indicates that our approach is suitable to extract candidates for robust discrimination between experiment classes. Next, we identify gene regulatory interactions using existing reconstruction algorithms aiming to extend the number of known gene-gene interactions for Treg cells. We applied eleven GRN reconstruction tools based on expression data only and compared their performance. Taken together, our results suggest that the available methods are not yet sufficient to extend the current knowledge by inferring so far unreported Treg specific interactions. Finally, we present an approach of integrating multiple data sets based on different high-throughput technologies to reconstruct a subtype-specific GRN. We constructed a Th2 cell specific gene regulatory network of 100 genes. While 89 of these are known to be related to Th2 cell differentiation, we were able to attribute 11 new candidate genes with a function in Th2 cell differentiation. We show that our approach to data integration does, in principle, allow for the reconstruction of a complex network. Future availability of more and more consistent data may enable the use of the concept of GRN reconstruction to improve understanding causes and mechanisms of cellular differentiation in the immune system and beyond and, ultimately, their dysfunctions and diseases.

A single abstract from the DHd-2016 Book of Abstracts., Sofern eine editorische Arbeit an dieser Publikation stattgefunden hat, dann bestand diese aus der Eliminierung von Bindestrichen in Überschriften, die aufgrund fehlerhafter Silbentrennung entstanden sind, der Vereinheitlichung von Namen der Autor*innen in das Schema "Nachname, Vorname" und/oder der Trennung von Überschrift und Unterüberschrift durch die Setzung eines Punktes, sofern notwendig., {"references":["https://doi.org/10.5281/zenodo.3679331","https://github.com/DHd-Verband/DHd-Abstracts-2016"]}

SummaryBackgroundPrevious studies have investigated the relationship between CYP2C19 polymorphism and clinical prognosis in coronary artery disease patients treated with clopidogrel, but the results were inconsistent.AimsTo assess the impact of CYP2C19 polymorphism on the risk of adverse clinical events by performing a meta-analysis of relevant studies in the last few years.MethodsProspective cohort studies or post-hoc analyses of randomized controlled trials were identified from the databases of PubMed/Medline, EMBASE and the Cochrane Library. Endpoints were fatal or non-fatal myocardial infarction, cardiovascular or all-cause death, definite or probable stent thrombosis, target vessel revascularization, target lesion revascularization, urgent revascularization, ischaemic stroke and bleeding. Pooled effects were measured by odds ratios (ORs) with 95% confidence intervals (CIs).ResultsA total of 21 studies involving 23,035 patients were included. Compared with non-carriers of the CYP2C19 variant allele, the carriers were found to have an increased risk of adverse clinical events (OR 1.50, 95% CI 1.21–1.87; P=0.0003), myocardial infarction (OR 1.62, 95% CI 1.35–1.95; P

Objective With increasing maternal antiretroviral treatment (ART), the number of children newly infected with HIV has declined. However, the possible increased mortality in the large number of HIV‐exposed, uninfected (HEU) children may be of concern. We quantified mortality risks among HEU children and reviewed associated factors. Methods Systematic search of electronic databases (PubMed, Scopus). We included all studies reporting mortality of HEU children to age 60 months and associated factors. Relative risk of mortality between HEU and HIV‐unexposed, uninfected (HUU) children was extracted where relevant. Inverse variance methods were used to adjust for study size. Random‐effects models were fitted to obtain pooled estimates. Results A total of 14 studies were included in the meta‐analysis and 13 in the review of associated factors. The pooled cumulative mortality in HEU children was 5.5% (95% CI: 4.0–7.2; I 2 = 94%) at 12 months (11 studies) and 11.0% (95% CI: 7.6–15.0; I 2 = 93%) at 24 months (four studies). The pooled risk ratios for the mortality in HEU children compared to HUU children in the same setting were 1.9 (95% CI: 0.9–3.8; I 2 = 93%) at 12 months (four studies) and 2.4 (95% CI: 1.1–5.1; I 2 = 93%) at 24 months (three studies). Conclusion Compared to HUU children, mortality risk in HEU children was about double at both age points, although the association was not statistically significant at 12 months. Interpretation of the pooled estimates is confounded by considerable heterogeneity between studies. Further research is needed to characterise the impact of maternal death and breastfeeding on the survival of HEU infants in the context of maternal ART, where current evidence is limited.

International audience; This study used the BIF-Beef data warehouse to determine whether semitendinosus (ST) was a muscle with a faster contraction speed and more glycolytic than longissimus thoracis (LT), regardless of the sex and breed of animals. With more than 500 animals from 7 breeds, we confirmed that LT was more oxidative than ST in males and females, but not in steers, and in all the breeds studied except Montbeliard. The LT had more slow oxidative (SO) and fewer fast oxido-glycolytic (FOG) and fast-glycolytic (FG) muscle fibres than the ST muscle, regardless of sex, in all breeds except Montbeliard and Holstein. SO proportion and the oxidative activity were negatively correlated to FG proportion and to the glycolytic activity. Similarly, FOG proportion was positively correlated to the glycolytic activity and negatively to FG proportion. However, these relationships are not consistent across sexes and breeds. In conclusion, differences in muscle types may be affected by sex or breed but to a moderate extent only.

Cette étude vise à déterminer les caractéristiques des objets de recherche en finance corporative des PME. La recherche porte sur 108 articles publiés durant les 10 dernières années dans six revues scientifiques de renom dans le domaine de l’entrepreneuriat et de la gestion des PME : Entrepreneurship Theory and Practice, International Small Business Journal, Journal of Business Venturing, Journal of Small Business Management, Revue internationale PME et Small Business Economics. Tous les objets de recherche ont été identifiés à partir du texte intégral des articles recueillis et classés a posteriori dans l’une ou l’autre des catégories suivantes : le capital de risque, la création d’entreprises, les conditions de financement, l’entre-preneurship, l’évaluation, la gestion financière, l’objectif financier, la performance financière, la recherche, la structure de capital et la structure organisationnelle. Ces objets de recherche ont aussi été analysés en fonction des recommandations de Pettit et Singer (1985) sur ce que devraient être les voies de recherche à emprunter en finance corporative des PME ; les écarts entre les pistes de recherche suggérées et les objets effectivement étudiés sont analysés et discutés. Les résultats font notamment ressortir la grande diversité des auteurs, une forte concentration autour d’un nombre restreint d’objets de recherche et un manque d’intérêt pour certaines autres voies de recherche jugées, par ailleurs, importantes pour le développement des connaissances en finance des PME., The purpose of this study is to determine the characteristics of the topics of study in SME’s corporate finance. This research is based on 108 papers published in the last 10 years in six prestigious scientific journals in the field of entrepreneurship and SME management: Entrepreneurship Theory and Practice, International Small Business Journal, Journal of Business Venturing, Journal of Small Business Management, Revue internationale PME and Small Business Economics. The integral text of the retained articles is the basis to identify its topic of research which is classified a posteriori in one of the following categories : venture capital, business start-up, financing conditions, entrepreneurship, valuation, financial management, financial objective, financial performance, research, capital structure and organi-zational structure. These topics of research are also analyzed relative to Pettit and Singer’s (1985) recommendations as to what should be the research avenues to be followed in SME’s corporate finance ; the gaps between the suggested research paths and the topics that were effectively studied are analyzed and discussed. The results show clearly the great diversity of authors, a strong concentration around a small number of research topics and a lack of interest for other avenues of research that are otherwise considered important for the development of knowledge in SME’s finance., Este estudio tiene como objetivo determinar las características de los tópicos de investigación en finanzas corporativa de las PyMEs. La investigación se basa en 108 artículos publicados, durante los últimos 10 años, en 6 revistas científicas reconocidas en el tópico del empresariado y de la administración de las PyMEs : Entrepreneurship Theory and Practice, International Small Business Journal, Journal of Business Venturing, Journal of Small Business Management, Revue internationale PME y Small Business Economics. Todos los tópicos de estudios son identi-ficados a partir del texto integral de los articulos recogidos y clasificados a posteriori en una u otra de las categorías siguientes : capital de riesgo, creación de empresas, condiciones de financiamiento, espíritu empresarial, evaluación, administración financiera, objetivo financiero, rendimiento financiera, investigación, estructura de capital y estructura organizacional. Estos tópicos de investigación son también analizados en función de las recomendaciones de Pettit et Singer (1985) sobre lo que tendrían que ser las vías de investigación basadas en las finanzas corporativas de las PyMEs ; las brechas entre las pistas de investigación sugeridas y los tópicos efectivamente estudiados son analizadas y discutidas. Los resultos hacen resaltar la grande diversidad de los autores, una fuerte concentración alrededor de un numero pequeño de tópicos de investigación y una falta de interés por ciertas otras vías de investigación juzgadas, por otro lado importantes para el desarrollo de los conocimientos en finanzas de las PyMEs., Diese Untersuchung hat sich zum Ziel gesetzt, die charakteristischen Merkmale von Finanzgenossenschaften bei kleinen und mittleren Unternehmungen zu bestimmen. Die Untersuchung basiert auf 108 publizierten Artikeln, die während den letzten 10 Jahren in sechs renommierten, wissenschaftlichen Zeitschriften im Bereich des Unternehmertums und der Führung von kleinen und mittleren Unternehmen veröffentlicht wurden: Entrepreneurship Theory and Practice, International Small Business Journal, Journal of Business Venturing, Journal of Small Business Management, Revue internationale PME und Small Business Economics.Alle Untersuchungsobjekte wurden unverkürzt aufgenommen und in folgende Kategorien klassiert: Risikokapital, Unternehmungsgründung, Finanzierungsbeding-ungen, Unternehmertum, Bewertung, Finanzielle Führung, Finanzielle Leistung, Forschung, Kapitalstruktur und organisationelle Struktur. Im weiteren wurden in Anlehnung an Pettit et Singer (1995) die Untersuchungsobjekte analysiert. Die Unterschiede zwischen den vorerst wahrgenommenen Forschungswegen und den effektiv studierten Untersuchungsobjekten wurden aufgezeigt und diskutiert.

Der Horizont der Reintegrationsforschung wird in jüngerer Zeit stark erweitert. Während frühere Arbeiten vor allem die Rückanpassung untersuchten, heben neuere Arbeiten andere Facetten des Karriereerfolgs hervor. An diesem Wendepunkt ist eine Konsolidierung der zwanzigjährigen Rückanpassungsforschung angebracht. Der Artikel legt die erste Metaanalyse der Rückanpassung vor und bereinigt die empirischen Primärstudien um Stichprobenfehler und Messfehler. Es bestätigen sich hohe Korrelationen zwischen der Arbeitsrückanpassung und vier zentralen Variablen: (1) Klarheit der Reintegrationsprogramme und -prozesse, (2) Rollenklarheit, (3) Rollenbezogene Entscheidungsfreiheit und (4) Rollenkonflikte. Für die Unternehmenspraxis zeigen die Ergebnisse Faktoren auf, mit denen Unternehmen die Rückanpassung ihrer Repatriates an das Heimatland unterstützen können. Für die Personal- und Managementforschung legt die Metaanalyse nahe, den empirischen Fokus auf andere Konstrukte des Reintegrationserfolgs zu verlagern. The scope of repatriation research has recently been broadened. Whereas previous research focused on readjustment, recent work emphasizes other facets of career success. At this turning point, consolidating two decades of readjustment research is appropriate. This article submits the first meta-analysis of readjustment and corrects the primary studies for sampling error and measurement errors. The results confirm high correlations between work adjustment and four core constructs: (1) clarity of repatriation programs and processes, (2) role clarity, (3) role discretion and (4) role conflicts. For business practice, these results point to key factors which firms can manage to facilitate readjustment. For human resource management research, this meta-analysis suggests shifting the focus of empirical research toward other constructs of repatriation success.

International audience; Les auteurs conduisent une méta-analyse sur la base de 751 élasticités à court terme et 402 à long terme concernant des publicités de marque visant directement le consommateur issues de 56 études publiées entre 1960 et 2008. L'étude met au jour plusieurs nouvelles généralisations à propos de L'élasticité publicitaire. Les plus importantes sont les suivantes: L'élasticité publicitaire à court terme moyenne est de 0,12, ce qui est substantiellement plus bas que la moyenne de la précédente méta-analyse de 0,22; il y a eu un déclin de L'élasticité publicitaire au cours du temps; et L'élasticité publicitaire est plus élevée (1) pour les produits durables plutôt que pour les produits non durables, (2) dans la première phase du cycle de vie plutôt que dans la phase de maturité, (3) pour les données annuelles plutôt que pour les données trimestrielles, et (4) quand L'élasticité est mesurée en points de couverture brute (PCB) plutôt qu'en termes monétaires. La moyenne de L'élasticité à long terme est de 0,24, ce qui est bien plus faible que la moyenne énoncée dans la méta-analyse précédente (0,41). Une grande part des résultats valables pour L'élasticité à court terme l'est pour L'élasticité à long terme, avec quelques exceptions notables. Les auteurs proposent une discussion des implications des ces résultats.

International audience; Trees act as ecosystem engineers and invasions by exotic tree species profoundly impact recipient communities. Recently, research on invasive trees has dramatically increased, enabling the assessment of general trends in tree invasion. Analysing 90 studies dealing with 45 invasive tree species, we conducted a quantitative review and a meta-analysis to estimate the relevance of eight leading hypotheses for explaining tree invasions. We also tested whether species functional traits (growth rate, density/cover, germination, biomass and survival) equally promote tree invasiveness. Overall, our results suggest that several hypotheses, linked to invasibility or invasiveness, are pertinent to explain tree invasions. Furthermore, more than one hypothesis has been supported for a given species, which indicates that multiple factors lead to the success of invasive tree species. In addition, growth rate appears to be the most efficient predictor of invasiveness for invasive trees and could thus be used as a means to identify potential alien tree invasions. We conclude that further investigations are needed to test the consistency of some hypotheses across a broader pool of invasive tree species, whilst experimental studies with the same tree species across a larger range of sites would help to reveal the full suite of factors that affect tree invasions.

International audience; Meta-analyses have been carried out to quantify the effect of dietary vitamin E on α-tocopherol accumulation and on lipid oxidation in porcine M. longissimus. Published results of 13 (vitamin E accumulation) and 10 (lipid oxidation) experiments respectively were used for the analyses. After a number of standardization procedures, a nonlinear relationship was found between the supplementary vitamin E and the accumulation of α-tocopherol in pork which approached a maximum value of 6.4 μg/g tissue. Pork lipid oxidation levels were described in terms of Thiobarbituric Acid Reacting Substances (TBARS) values. The statistical analysis revealed significant effect of vitamin E dose, muscle α-tocopherol concentration and supplementation time on TBARS, resulting in two prediction models for lipid oxidation. Meta-analysis has proven to be a valuable tool for combining results from previous studies to quantify the effects of dietary vitamin E. Further studies, carried out with standardized experimental protocols would be beneficial for model validation and to increase the predictive power of the derived models.

International audience; La perspective structurationniste en SI permet de postuler que les transformations touchent des aspects ? la fois micro, méso et macro-organisationnels et que ces différents niveaux de transformation sont récursifs. Ce cadre théorique est mobilisé dans un nombre croissant de travaux de recherche empiriques contextualisés. Il est alors difficile de dégager des tendances en termes de domaines de transformations induites par des TIC dans des contextes stabilisés (phase de post-implémentation). Cet article a deux objectifs. D'une part, il s'agit de montrer l'intérêt pour appréhender les e-transformations, des méta-analyses et notamment des méta-analyses qualitatives identifiées dans le champ académique sous l'appellation de «méta-synthèse». Cette méthodologie spécifique a été testée ici dans le contexte de la gestion de la relation client ou du Customer Relationship Management (CRM) et permet de dégager des tendances internationales et inter-sectorielles. D'autre part, le second objectif de cet article est d'analyser les domaines et les modes/mécanismes de transformation en jeu dans le contexte du CRM. Cette recherche apporte trois contributions principales: 1) montrer que les transformations socio-organisationnelles en contexte CRM peuvent être regroupées en quatre grands domaines distincts de transformation; 2) montrer le caractère direct/indirect de ces transformations dans chacun de ces quatre domaines et approfondir les mécanismes de transformations indirectes (apprentissage de second niveau versus effets en cascade et systémiques) et 3) montrer l'existence de liens récursifs entre ces quatre domaines de transformation.

Summary Background While there are convergent data suggesting that overall cardiovascular mortality is increased in patients with rheumatoid arthritis, the relative contributions of myocardial infarction and stroke remain unclear. Aims We sought to clarify this issue by conducting a meta-analysis of cohort studies on myocardial infarction and stroke in patients with rheumatoid arthritis. Methods A MEDLINE search from January 1960 to September 2009 and abstracts from international conferences from 2007 to 2009 were searched for relevant literature. All cohort studies reporting on standardized mortality ratio or incidence rate ratio of myocardial or stroke associated with rheumatoid arthritis, with available crude numbers, were included. STATA meta-analysis software was used to calculate pooled risk estimates. Results Seventeen papers fulfilled the inclusion criteria, corresponding to a total of 124,894 patients. Ten studies reported on standardized mortality ratio for fatal myocardial infarction, which ranged from 0.99 to 3.82. The overall pooled estimate was 1.77 (95% confidence interval [CI] 1.65–1.89). Incidence rate ratio for myocardial infarction was reported in five studies; the pooled estimate was 2.10 (95% CI 1.52–2.89). Nine studies reported on fatal stroke, with standardized mortality ratio ranging from 1.08 to 2.00; the pooled estimate was 1.46 (95% CI 1.31–1.63). The pooled incidence rate ratio for stroke (three studies) was 1.91 (95% CI 1.73–2.12). Conclusion Our results show that risks of myocardial infarction and stroke are increased in patients with rheumatoid arthritis. In addition, both account for the observed increased mortality in individuals with rheumatoid arthritis.

International audience; Numerous experiments have studied the use of oilseed supplements in cow diets to alter milk fatty acid (FA) composition, but no quantitative synthesis of these studies is currently available. This article reports a meta-analysis of the response of cow milk FA composition to oilseed lipid supplements from linseed, rapeseed, soybeans, and sunflower seed. First, from a database of 145 oilseed supplementation experiments, we collected the mean FA percentages observed with unsupplemented diets and diets supplemented with the 4 oilseeds given as seeds (after various types of processing), as oils (including Ca salts and amides), or in protected forms. Second, we studied the response of the major milk FA percentages to increasing amounts of supplemental lipids from the 4 oilseeds. Responses were nonsignificant, linear, or quadratic, depending on the FA studied and the supplement. Effects of interfering factors, such as supplement form, forage component of the diet, or lactation stage, were difficult to assess from the available data. Third, we studied the response of the major milk FA percentages to increasing dietary intakes of linoleic or linolenic acids, taken separately. Overall, these results confirm the high plasticity of milk FA composition, with the widest variations being observed in the percentages of medium-chain versus C18 FA, and among the C18 in 18: 0, cis-18:1, and trans-18:1. The percentages of the polyunsaturated FA cis-9 cis-12-18:2 and 18:3 were less variable, except when protected lipids (mostly formaldehyde treated) were supplied. However, trans-18:1 and polyunsaturated FA (including conjugated linoleic acid) exhibited the greatest variations when expressed relative to their respective basal values (for unsupplemented diets). Oils, compared with seeds, induced greater percentages of trans-18: 1 and tended to decrease C6 to C12 FA more. Intakes of 18:2- and 18:3- rich lipid sources did not differ greatly in their effects on short- and medium-chain FA and trans-18:1 percentages, although the profiles of individual 18:1 and 18:2 isomers in milk differed. This meta-analysis provides quantitative estimates, obtained from the extensive literature produced over more than 40 yr, of the impact of oilseed supplements on milk FA composition.

SummaryDementia is one of the most common neurological disorders in the elderly. Aging is associated with a large increase in the prevalence and incidence of degenerative (Alzheimer's disease) and vascular dementia, leading to a devastating loss of independence. In view of increasing longevity of populations worldwide, prevention and treatment of dementia has turned into a major public health challenge. In the past decade, longitudinal studies have shown a close association between high blood pressure in middle age, cognitive decline and dementia, including Alzheimer's disease, in the late life. Pathophysiologically, a summation of cerebrovascular damage, white matter changes and pre-existing asymptomatic Alzheimer's brain lesions may lead to dementia, even when each type of lesion individually is not sufficiently severe to cause it. Longitudinal studies assessing the beneficial role of antihypertensive drugs on cognitive decline and dementia have produced promising results. There are few randomised placebo controlled studies, although some of these have produced positive results. Results of three recent meta-analyses are inconsistent, possibly due to methodological issues. Further long-term randomised trials, designed especially to assess a link between antihypertensive therapy and cognitive decline or dementia are therefore needed.

e-mail: meglecz@up.univ-mrs.fr; International audience; Although microsatellites are ubiquitous in eukaryota, the number of available markers varies strongly among taxa. This meta-analysis was conducted on 32 insect species. Sequences were obtained from two assembled whole genomes, whole genome shotgun (WGS) sequences from 10 species and screening partial genomic libraries for microsatellites from 23 species. We have demonstrated: (1) strong differences in the abundance of microsatellites among species; (2) that microsatellites within species are often grouped into families based on similarities in their flanking sequences; (3) that the proportion of microsatellites grouped into families varies strongly among taxa; and (4) that microsatellite families were significantly more often associated with transposable elements - or their remnants - than unique microsatellite sequences

BackgroundParticularly in developing countries, lower birthweight may be associated with higher neonatal mortality, and deliveries frequently take place at home where scales are not always available. Therefore, surrogate measurements for birthweight are necessary as a primary screening measure. The aim of this study was to determine whether newborn chest and arm circumferences can predict birthweight less than 2000g.MethodsThe selection criteria were studies published in English that could provide all the true- and false-positive and true- and false-negative results with regard to the prediction of birthweight less than 2000g by other anthropometric measurements among apparently healthy neonates. Ten bibliographic databases (e.g., PubMed) were searched and a bivariate meta-analysis was conducted with hierarchical summary receiver operating characteristic (ROC) curves. A total of 36,987 participants in 24 studies for chest circumference and 16,164 participants in 15 studies for arm circumference were included. The study regions were limited to Africa and Asia.ResultsFor chest and arm circumferences (24 and 15 studies, respectively), pooled sensitivity (0.94 and 0.89, respectively) and specificity (0.94 and 0.96, respectively), and diagnostic odds ratios (263 and 174, respectively) were sufficiently high to allow good predictions. The diagnostic odds ratio for chest circumference was significantly higher than for arm circumference (P

Background. A number of parenting programs, aimed at improving parenting competencies,have recently been adapted or designed with the use of online technologies. Although webbased services have been claimed to hold promise for parent support, a meta-analytic review of online parenting interventions is lacking. Method. A systematic review was undertaken of studies (n= 19), published between 2000 and 2010, that describe parenting programs of which the primary components were delivered online. Seven programs were adaptations of traditional, mostly evidence-based, parenting interventions, using the unique opportunities of internet technology. Twelve studies (with in total 54 outcomes, Ntot parents = 1,615 and Ntot children = 740) were included in a meta-analysis. Results. The meta-analysis showed a statistically significant medium effect across parents outcomes (ES = 0.67; se = 0.25) and child outcomes (ES = 0.42; se = 0.15). Conclusions. The results of this review show that webbased parenting programs with new technologies offer opportunities for sharing social support, consulting professionals and training parental competencies. The meta-analytic results show that guided and self-guided online interventions can make a significant positive contribution for parents and children. The relation with other meta-analyses in the domains of parent education and web-based interventions is discussed.

Background: This paper contributes to the evidence-base on prices and alcohol use by presenting meta-analytic summaries of price and income elasticities for alcohol beverages. The analysis improves on previous meta-analyses by correcting for outliers and publication bias. Methods: Adjusting for outliers is important to avoid assigning too much weight to studies with very small standard errors or large effect sizes. Trimmed samples are used for this purpose. Correcting for publication bias is important to avoid giving too much weight to studies that reflect selection by investigators or others involved with publication processes. Cumulative meta-analysis is proposed as a method to avoid or reduce publication bias, resulting in more robust estimates. The literature search obtained 182 primary studies for aggregate alcohol consumption, which exceeds the database used in previous reviews and meta-analyses. Results: For individual beverages, corrected price elasticities are smaller (less elastic) by 28-29 percent compared with consensus averages frequently used for alcohol beverages. The average price and income elasticities are: beer, -0.30 and 0.50; wine, -0.45 and 1.00; and spirits, -0.55 and 1.00. For total alcohol, the price elasticity is -0.50 and the income elasticity is 0.60. Conclusions: These new results imply that attempts to reduce alcohol consumption through price or tax increases will be less effective or more costly than previously claimed.

Background. A number of parenting programs, aimed at improving parenting competencies,have recently been adapted or designed with the use of online technologies. Although webbased services have been claimed to hold promise for parent support, a meta-analytic review of online parenting interventions is lacking. Method. A systematic review was undertaken of studies (n= 19), published between 2000 and 2010, that describe parenting programs of which the primary components were delivered online. Seven programs were adaptations of traditional, mostly evidence-based, parenting interventions, using the unique opportunities of internet technology. Twelve studies (with in total 54 outcomes, Ntot parents = 1,615 and Ntot children = 740) were included in a meta-analysis. Results. The meta-analysis showed a statistically significant medium effect across parents outcomes (ES = 0.67; se = 0.25) and child outcomes (ES = 0.42; se = 0.15). Conclusions. The results of this review show that webbased parenting programs with new technologies offer opportunities for sharing social support, consulting professionals and training parental competencies. The meta-analytic results show that guided and self-guided online interventions can make a significant positive contribution for parents and children. The relation with other meta-analyses in the domains of parent education and web-based interventions is discussed.

Cet article propose de comprendre comment les recherches se saisissent du concept de génération en organisation. Cette méta-analyse repose sur une grille d’analyse conceptuelle qui permet aux auteurs de classer 65 articles selon les niveaux (société, carrière, organisation, et poste) et les dimensions (âge, cohorte, et période/événement) générationnelles auxquels les articles analysés se rapportent. Les résultats laissent apparaître des conceptualisations variées de la notion de génération dans les recherches en management, mais aussi une focalisation sur les dimensions d’âge et de cohorte au niveau sociétal. Des explications peuvent être trouvées dans la désynchronisation récente des dimensions et niveaux générationnels, la jeunesse des modèles théoriques, les raccourcis conceptuels amplifiés par les médias, et par le format des dispositifs méthodologiques employés par les chercheurs. Cet article offre aux chercheurs et praticiens une vision plus « réaliste » car plus complexe du phénomène générationnel en organisation et met en évidence des domaines de recherche qui demeurent inexplorés.

Despite their major contribution to the energy supply of ruminants, the production of volatile fatty acids (VFA) in the rumen is still poorly predicted by rumen models. We have developed an empirical approach, based on the interpretation of large bibliographic databases gathering published in vivo measurements of ruminal VFA production rate (PR), rates of duodenal and faecal digestion and molar percentages of VFA in the rumen. These databases, covering a wide range of intake levels and dietary composition, were studied by meta-analysis using within-experiment models. We established models to quantify response laws of total VFA-PR and individual VFA molar percentages in the rumen to variations in intake level and dietary composition. The rumen fermentable organic matter (RfOM) intake, estimated from detailed knowledge of the chemical composition of diets according to INRA Feed Tables, appears as an accurate explanatory variable of measured total VFA-PR, with an average increment of 8.03 ± 0.64 mol total VFA/kg RfOM intake. Similar results were obtained when total VFA-PR was estimated from measured apparent RfOM (total VFA-PR/RfOM averaging 8.3 ± 1.2 mol/kg). The VFA molar percentages were related to dry matter intake and measured digestible organic matter (OM), digestible NDF and rumen starch digestibility, with root mean square error of 1.23, 1.45, 0.88 and 0.41 mol/100 mol total VFA for acetate, propionate, butyrate and minor VFA, respectively, with no effect of pH on the residuals. Stoichiometry coefficients were calculated from the slopes of the relationships between individual VFA production (estimated from measured apparent RfOM and individual VFA molar percentages) and measured fermented fractions. Coefficients averaged, respectively, 66, 17, 14 and 3 mol/100 mol for NDF; 41, 44, 12 and 4 mol/100 mol for starch; and 46, 35, 13 and 6 mol/100 mol for crude protein. Their use to predict VFA molar percentages appear relevant for most dietary conditions, that is, when the digested NDF/digested OM ratio exceeded 0.12. This study provides a quantitative review on VFA yield in the rumen. It contributes to the development of feed evaluation systems based on nutrient fluxes.

Pollution relative to phosphorus excretion in poultry manure as well as the soaring prices of phosphate, a non-renewable resource, remain of major importance. Thus, a good understanding of bird response regarding dietary phosphorus (P) is a prerequisite to optimise the utilisation of this essential element in broiler diets. A database built from 15 experiments with 203 treatments was used to predict the response of 21-day-old broilers to dietary non-phytate P (NPP), taking into account the main factors of variation, calcium (Ca) and microbial phytase derived from Aspergillus niger, in terms of average daily feed intake (ADFI), average daily gain (ADG), gain to feed (G:F) and tibia ash concentration. All criteria evolve linearly (P < 0.001) and quadratically (P < 0.001) with dietary NPP concentration. Dietary Ca affected the intercept and linear component for ADG (P < 0.01), G:F (P < 0.05) and tibia ash concentration (P < 0.001), whereas for ADF1, it affected only the intercept (P < 0.01). Microbial phytase addition impacted on the intercept, the linear and the quadratic coefficient for ADF1 (P < 0.01), ADG (P < 0.001) and G:F (P < 0.05), and on the intercept and the linear component (P < 0.001) for tibia ash concentration. An evaluation of these models was then performed on a database built from 28 experiments and 255 treatments that were not used to perform the models. Results showed that ADFI, ADG and Tibia ash concentration were predicted fairly well (slope and intercept did not deviate from 0 to 1, respectively), whereas this was not the case for G:F. The increase in dietary Ca concentration aggravated P deficiency for all criteria while phytase addition had a positive effect. The more P deficiency was marked, the more the bird response to ADFI, ADG, G:F and tibia ash concentration was exacerbated. It must also be considered that even if the decrease in dietary Ca may improve P utilisation, it could in turn become limiting for bone mineralisation. In conclusion, this meta-analysis provides ways to reduce dietary P in broiler diets without impairing performance, taking into account dietary Ca and microbial phytase.

Self-control theory is one of the best studied criminological paradigms. Since Gottfredson and Hirschi published their General Theory in 1990 the theory has been tested on more than a million subjects. This meta-study systematizes the evidence, reporting 717 results from 102 different publications that cover 966,364 original data points. The paper develops a methodology that makes it possible to standardize findings although the original papers have used widely varying statistical procedures, and have generated findings of very different precision. Overall, the theory is overwhelmingly supported, but the effect is relatively small, and is sensitive to adding a host of moderating variables.

This paper provides a quantitative review of the empirical evidence on the impact of taxation on corporate debt finance. On the basis of 626 primary estimates taken from 23 studies, we find that the median tax-rate elasticity of debt ratios is around 0.44. The median tax-rate elasticity of incremental debt changes amounts to 2.47. There is, however, considerable variation in estimated tax effects on financial leverage. By means of meta-regressions, the paper aims to systematically explain this variation in terms of underlying study characteristics. The meta-regressions indicate that the heterogeneity in the semi-elasticities from the different studies can be fairly well explained by the characteristics of these studies. We find that the estimated tax elasticities are more pronounced if large firms or holding companies are considered. Moreover, our results suggest significantly higher tax elasticities of intercompany debt supporting the view that tax planning strategies of multinational firms affect debt financing.

Research on the cross-functionality - new product performance relationship reports contradictory results. The meta-analysis highlights some theoretical and methodological moderating variables. If the identification by Troy, Hirunyawipada, and Paswan (2008) of theoretical moderators that affect this relationship seems comprehensive, it is not for methodological factors. We assess the moderating effect of 24 moderators, 16 of which are methodological, which could impact the relationship between cross-functional integration and new product performance., Les recherches consacrées à la relation inter-fonctionnalité - performance d'un nouveau produit font état de résultats contradictoires. Si le recensement des contingences théoriques affectant cette relation par Troy, Hirunyawipada et Paswan (2008) semble exhaustif, celui des facteurs méthodologiques est partiel. Nous évaluons l'effet de 24 modérateurs, dont 16 sont méthodologiques, qui pourraient affecter la relation entre intégration inter-fonctionnelle et performance du nouveau produit.

(VF)Ce papier combine trois types de méta-analyses pour étudier le lien entre la participation budgétaire et la performance managériale. Il permet de mettre en application certaines préconisations du forum international de Potsdam (1994) sur la méta-analyse en contrôle de gestion. Après une présentation des méthodes de méta-analyse utilisées et des articles compilées, trois synthèses ont été réalisées sur le lien entre la participation budgétaire et la performance managériale. Nous mettons en particulier en œuvre la « synthèse des meilleures études » préconisée par Slavin (1995). Cette triangulation de différentes méta-analyses amène à conclure à un lien positif significatif entre la participation budgétaire et la performance managériale. Nous discutons du traitement de l’hétérogénéité persistant dans les résultats de la «synthèse des meilleures études». La présence de contingences culturelles pourrait expliquer cette hétérogénéité.(VA)This paper is a combination of three methodologies of quantitative synthesis to study the link between budgetary participation and managerial performance. It applies some propositions of the Potsdam international congress on meta-analysis in the field of management control. After an overview of the used methods of meta-analysis and a review of literature, three syntheses were realised on the link between budgetary participation and managerial performance. Particularly, we implement the “best-evidence synthesis” recommended by Slavin (1995). The triangulation of various meta-analyses leads to conclude to a significant positive impact of the budgetary participation on the managerial performance. We additionally discuss the treatment of persistent heterogeneity in the result of the “best evidence synthesis”. The presence of cultural contingencies could explain this persistent heterogeneity.

International audience; La messagerie électronique s'est rapidement développée dans les organisations aux cours de ces dix dernières années, par sa facilité d'utilisation et son utilité perçue. Pourtant, Weber publie en 2004 un article dans le MIS Quaterly dans lequel il soulève : " Curieusement, les recherches sur la messagerie électronique sont peu significatives en systèmes d'information ". Il invite alors les chercheurs à publier davantage sur " l'e-mail ". Cet article présente une méta-analyse des travaux de recherche francophones sur la période 2000-2008. Nous étudions l'usage de la messagerie électronique dans les organisations à l'aide d'une analyse statistique des données textuelles. Dans un premier temps, nous expliquons l'originalité de cette démarche et le traitement des données. Dans un deuxième temps, nous présentons les résultats et les profils de classes obtenus par Alceste : quatre classes différentes, correspondant à quatre grands sujets de recherche : " Temps et productivité ", " Choix des médias et productivité " ; " Utilisation/satisfaction ", " Interface homme/machine ". Enfin, nous discutons des résultats, de la validité et des limites de cette démarche. Ceci ouvre des pistes de réflexions et des voies de recherches futures.

Over the last 25 years, more than a hundred dictator game experiments have been published. This meta study summarizes the evidence. Exploiting the fact that most experiments had to fix parameters they did not intend to test, in multiple regression the meta study is able to assess the effect of single manipulations, controlling for a host of alternative explanatory factors. The resulting rich dataset also provides a testbed for comparing alternative specifications of the statistical model for analysing dictator game data. It shows how Tobit models (assuming that dictators would even want to take money) and hurdle models (assuming that the decision to give a positive amount is separate from the choice of amount, conditional on giving) provide additional insights.

The European Commission is working on a revision of its Guidelines on Research and Development Agreements. On this occasion, this note surveys the existing experimental evidence. Experiments add a number of additional arguments to the normative assessment. R&D agreements have a much smaller effect on later competition in the product market if they serve as a substitute for incomplete (legal) protection of innovation effort. They may help firms settle the resulting fairness issue, and stay away from investment wars. Using the results from 107 published experiments on oligopoly, a meta-study shows that clearing an R&D agreement can be beneficial since it removes the additional collusion incentive resulting from fear that, through successful innovation, competitors might gain an advantage. This is the case if the opposite market side has countervailing power, and the more market conditions are stable. By contrast, the meta-data suggests that R&D agreements increase the risk of collusion in the product market if products are substitutes, if capacity cannot immediately be extended, if market participants may communicate, and if they are experienced; the latter two conditions are very likely to hold in the field.

Despite the abundant literature on the impact of subsidies on world cotton prices, there is no consensus on the quantification of that impact. Our article describes a meta-analysis aimed at explaining the lack of consensus. We also identify the key factors needed to describe cotton-price dynamics, and report our results concerning the effect of subsidies. We show that the variations between studies are mainly due to the choice of elasticity values, the size of the subsidies, and inclusion of certain key factors. Effective modeling requires a precise estimation of elasticities and the inclusion of determinants of world cotton prices such as inventory levels and the price of polyester., Malgré le nombre important d’études sur les impacts des subventions sur le prix mondial du coton, il n’existe pas de consensus concernant la quantification de ces effets. L’objectif de cet article est de réaliser une méta-analyse capable d’expliquer la source de l’hétérogénéité des résultats, de donner des indications quant aux variables indispensables à la modélisation, mais aussi de présenter un chiffrage des effets des subventions. Nous montrons que les valeurs des élasticités, les montants des subventions et l'incorporation de certains facteurs-clés sont les sources principales des variations inter-études. Une modélisation appropriée requiert ainsi une estimation précise des élasticités et l’intégration de certains facteurs constitutifs du prix mondial du coton tels que les niveaux de stocks ou le prix du polyester., Guerreiro David. Une méta-analyse de l’impact des subventions sur le prix mondial du coton . In: Économie & prévision, n°195-196, 2010-4-5. pp. 111-125.

L’impact négatif de la distance sur le commerce bilatéral constitue l’un des résultats empiriques les plus robustes en économie internationale. Bien que connu, ce résultat n’a cependant fait l’objet d’aucune analyse systématique. Les auteurs examinent 1 467 effets distance estimés dans 103 articles de recherche. Les informations collectées pour chaque coefficient permettent de tester différentes hypothèses sur les causes de variation de ces effets distance entre les études. L’analyse montre que l’impact négatif de la distance sur le commerce a cru vers le milieu du 20e siècle et est resté élevé depuis., One of the best-established empirical results in international economics is that bilateral trade decreases with distance. Although well known, this result has not been systematically analyzed before. We examine 1,467 distance effects estimated in 103 papers. Information collected on each estimate allows us to test hypotheses about the causes of variation in the estimates. Our most interesting finding is that the estimated negative impact of distance on trade rose around the middle of the century and has remained persistently high since then. This result holds even after controlling for many important differences in samples and methods.

(VF)Les restructurations occupent une place centrale dans la vie des entreprises occidentales. Or, les preuves de leur capacité à améliorer ou redresser les performances restent ténues et la littérature empirique apporte des résultats ambigus et parfois contradictoires. Cet article a pour but d’explorer cette littérature en recourant aux outils de la méta-analyse. Il ressort de l’examen de 52 publications académiques que les restructurations ne se révèlent positives qu’à long terme et lorsque l’opération s’inscrit dans une reconfiguration de l’organisation. Par ailleurs, leur incidence sur les cours boursiers, contrairement à l’idée couramment admise, est plutôt négative, les marchés marquant leur méfiance à l’égard d’opérations trop simplistes et potentiellement révélatrices de difficulté. Il ressort de ces résultats que les restructurations ne sont efficaces qu’à la condition d’être mises en œuvre de façon proactive.(VA)Downsizing is now an important feature of western economies. However, their economic outcomes remain uncertain, as past academic empirical literature leads to ambiguous and sometimes contradictory results. This article aims at examining this literature using meta-analysis. It is shown from a 52-publication sample that downsizing leads to positive outcomes on the long run only, and when it is included in a wide organizational change process. Further, the effects of downsizing on shareholders’ wealth are negative, contrary to popular belief. Investors seem worried about too simplistic operations that may reveal previously unknown difficulties. Finally, our results show that downsizing is more about to be efficient when implemented in a proactive way.

Gaat het wel goed met ons onderwijs? Uit internationaal vergelijkend onderzoek naar leerresultaten (PISA) blijkt dat Nederland op de ranglijst daalt. Dat betekent dat of ons onderwijs achteruitgaat, of dat het onderwijs in het buitenland in vergelijking met ons onderwijs beter wordt. In de media heeft iedereen een mening en wijst lukraak een 'schuldige' aan: het te vaak uitvallen van lessen, gebrek aan vakkennis bij de leraar, feminisering van het onderwijs, tekortkomingen in de opleiding van leraren ... Maar wat is nu echt bekend over de belangrijkste invloeden op de leerresultaten van leerlingen?