The relationship between collaboration, productivity and publications: an empirical analysis in field of family business

Purpose: It is widely accepted that coauthorship and collaboration promotes intellectual partnerships and improves the quality of publications. This paper examines the relationship between collaboration, productivity and publications in the field of family business. Design/methodology/approach: The authors identify the most prolific authors, affiliations and countries and focus on the evolution of research in the field of family business. In doing so, the authors employ social network analysis to discover the structure of the networks and the ways in which authors, institutions and countries interact. Findings: The empirical results show that collaboration is positively related to productivity, and there is significant evidence that the shaped networks exhibit small-world characteristics, a condition in which collaboration within authors becomes integrated in conjunction with time. Practical implications: The findings highlight the mechanics of collaborative research production and can be useful to understand the importance of collaboration patterns to be followed in the field of family business. Originality/value: The contributions are as follows: (a) application of social network analysis to model the coauthorship patterns among individuals, institutions and countries in family business; (b) distinguishing the most degree-central authors in the social network of collaborating academics; (c) investigation of the academic collaborations in family business that have the characteristics of a small-world social network and (d) suggesting a unique connection, through published keywords, between the research priorities of the most central or prolific authors with the research trends in the family business literature. The authors demonstrate that authors\u27 collaboration becomes integrated in conjunction with time

Obstetric outcomes after treatment of periodontal disease during pregnancy: systematic review and meta-analysis

Objective To examine whether treatment of periodontal disease with scaling and root planing during pregnancy is associated with a reduction in the preterm birth rate

Multi-disciplinary optimization of variable rotor speed and active blade twist rotorcraft: Trade-off between noise and emissions

The concepts of variable rotor speed and active blade twist are emerging technologies for the next generation of civil rotorcraft. Previous research has focused on the optimum implementation of these technologies for improved fuel economy and environmental impact. Within this work, an integrated approach is deployed to quantify the concurrent reductions in rotor noise and NOx emissions. A relaxation-based free-wake inflow model, coupled with unsteady blade aerodynamics modeling, resolves the flow-field around the main rotor. Aero-acoustic predictions are performed through an acoustic-analogy-based formulation. Gaseous emissions are then predicted via stirred-reactor modeling, coupled with zero-dimensional engine performance analysis method. This strategy is incorporated into a multi-disciplinary genetic algorithm optimization process based on surrogate modeling. Optimal schedules of combined variable rotor speed and active blade twist controls are derived for a twin-engine light helicopter in descent. The accrued schedules suggest NOx reductions between 6% and 21%, simultaneously with source-noise reductions of the order of 2–8 dB, relative to the non-morphing rotor case. The developed strategy constitutes an enabling methodology for the holistic and multi-disciplinary assessment of morphing helicopter rotor configurations

Composite macroH2A/NRF-1 Nucleosomes Suppress Noise and Generate Robustness in Gene Expression

SummaryThe histone variant macroH2A (mH2A) has been implicated in transcriptional repression, but the molecular mechanisms that contribute to global mH2A-dependent genome regulation remain elusive. Using chromatin immunoprecipitation sequencing (ChIP-seq) coupled with transcriptional profiling in mH2A knockdown cells, we demonstrate that singular mH2A nucleosomes occupy transcription start sites of subsets of both expressed and repressed genes, with opposing regulatory consequences. Specifically, mH2A nucleosomes mask repressor binding sites in expressed genes but activator binding sites in repressed genes, thus generating distinct chromatin landscapes that limit genetic or extracellular inductive signals. We show that composite nucleosomes containing mH2A and NRF-1 are stably positioned on gene regulatory regions and can buffer transcriptional noise associated with antiviral responses. In contrast, mH2A nucleosomes without NRF-1 bind promoters weakly and mark genes with noisier gene expression patterns. Thus, the strategic position and stabilization of mH2A nucleosomes in human promoters defines robust gene expression patterns

Suspended monolayer graphene under true uniaxial deformation

2D crystals, such as graphene, exhibit the higher strength and stiffness of any other known man-made or natural material. So far, this assertion has been primarily based on modelling predictions and on bending experiments in combination with pertinent modelling. True uniaxial loading of suspended graphene is not easy to accomplish; however such an experiment is of paramount importance in order to assess the intrinsic properties of graphene without the influence of an underlying substrate. In this work we report on uniaxial tension of graphene up to moderate strains of 0.8% ca.. This has been made possible by sandwiching the graphene flake between two polymethylmethacrylate (PMMA) layers and by suspending its central part by the removal of a section of PMMA with e-beam lithography. True uniaxial deformation is confirmed by the measured large phonon shifts with strain by Raman spectroscopy and the indication of lateral buckling (similar to what is observed for thin macroscopic membranes under tension). Finally, we also report on how the stress is transferred to the suspended specimen through the adhesive grips and determine the value of interfacial shear stress that is required for efficient axial loading in such a system

Association between Helicobacter pylori Infection and Nasal Polyps: A Systematic Review and Meta-Analysis.

BACKGROUND Helicobacter pylori (H. pylori) has definite or possible associations with multiple local and distant manifestations. H. pylori has been isolated from multiple sites throughout the body, including the nose. Clinical non-randomized studies with H. pylori report discrepant data regarding the association between H. pylori infection and nasal polyps. The aim of this first systematic review and meta-analysis was the assessment of the strength of the association between H. pylori infection and incidence of nasal polyps. METHODS We performed an electronic search in the three major medical databases, namely PubMed, EMBASE and Cochrane, to extract and analyze data as per PRISMA guidelines. RESULTS Out of 57 articles, 12 studies were graded as good quality for analysis. Male-to-female ratio was 2:1, and age ranged between 17-78 years. The cumulative pooled rate of H. pylori infection in the nasal polyp group was 32.3% (controls 17.8%). The comparison between the two groups revealed a more significant incidence of H. pylori infection among the nasal polyp group (OR 4.12), though with high heterogeneity I$^{2}$ = 66%. Subgroup analysis demonstrated that in European studies, the prevalence of H. pylori infection among the nasal polyp group was significantly higher than in controls, yielding null heterogeneity. Subgroup analysis based on immunohistochemistry resulted in null heterogeneity with preserving a statistically significant difference in H. pylori infection prevalence between the groups. CONCLUSION The present study revealed a positive association between H. pylori infection and nasal polyps

Pooled Analysis of Elderly Patients with Non-small Cell Lung Cancer Treated with Front Line Docetaxel/Gemcitabine Regimen: The Hellenic Oncology Research Group Experience

IntroductionThirty to 40% of patients with non-small cell lung cancer (NSCLC) are older than 70 years and rarely are enrolled in clinical trials. Moreover, in clinical practice, >75% of patients older than 65 years with metastatic NSCLC never receive any kind of chemotherapy.PurposeTo retrospectively evaluate the impact of age on efficacy and toxicity of chemotherapy regimens in patients with advanced NSCLC treated with the docetaxel-gemcitabine combination.Patients and MethodsPooled data from six clinical trials of the Hellenic Oncology Research Group were analyzed. According to their age, patients were divided into two groups: those with age <70 years and those with ≥70 years.ResultsA total of 858 patients were included in this analysis. Six hundred sixty-six (77.6%) patients were younger than 70 years, whereas 192 (22.4%) patients where ≥70-year-old. Overall response rate was 30.3% and 30.2% for patients <70 years and ≥70 years, respectively (p = 0.974). The median time to tumor progression was 4.1 and 4.5 months for patients <70 years and ≥70 years, respectively (p = 0.948). Median overall survival was 9.9 and 9.2 months for patients <70 and ≥70, respectively (p = 0.117). The multivariate analysis revealed performance status (PS) (p = 0.0001) and stage (p = 0.0001) as independent factors with significant impact on the hazard of death. Chemotherapy was well tolerated, but the incidence of grade III/IV mucositis was significantly higher in elderly patients (0.2% versus 1.5% for patients <70 versus ≥70 years, respectively; p = 0.011).ConclusionThe docetaxel/gemcitabine regimen has a comparable efficacy and tolerance in young (<70 years) and elderly (≥70 years) patients

Trimebutine maleate monotherapy for functional dyspepsia: A multicenter, randomized, double-blind placebo controlled prospective trial

Background and Objectives:Functional dyspepsia (FD) is one of the most common functional gastrointestinal disorders; it has a great impact on patient quality of life and is difficult to treat satisfactorily. This study evaluates the efficacy and safety of trimebutine maleate (TM) in patients with FD.Materials and Methods: A multicenter, randomized, double-blind, placebo controlled, prospective study was conducted, including 211 patients with FD. Participants were randomized to receive TM 300 mg twice per day (BID, 108 patients) or placebo BID (103 patients) for 4 weeks. The Glasgow Dyspepsia Severity Score (GDSS) was used to evaluate the relief of dyspepsia symptoms. Moreover, as a pilot secondary endpoint, a substudy (eight participants on TM and eight on placebo) was conducted in to evaluate gastric emptying (GE), estimated using a 99mTc-Tin Colloid Semi Solid Meal Scintigraphy test.Results: Of the 211 patients enrolled, 185 (87.7%) (97 (52.4%) in the TM group and 88 (47.6%) in the placebo group) completed the study and were analyzed. The groups did not differ in their demographic and medical history data. Regarding symptom relief, being the primary endpoint, a statistically significant reduction in GDSS for the TM group was revealed between the first (2-week) and final (4-week) visit (p-value = 0.02). The 99 mTc-Tin Colloid Semi Solid Meal Scintigraphy testing showed that TM significantly accelerated GE obtained at 50 min (median emptying 75.5% in the TM group vs. 66.6% in the placebo group,p= 0.036). Adverse effects of low to moderate severity were reported in 12.3% of the patients on TM.Conclusion: TM monotherapy appears to be an effective and safe approach to treating FD, although the findings presented here warrant further confirmation.Galenica A.E. Pharmaceutical Compan