Collaboration in sensor network research: an in-depth longitudinal analysis of assortative mixing patterns

Many investigations of scientific collaboration are based on statistical analyses of large networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustrate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a relatively small network of scientific collaboration (N = 291) constructed from the bibliographic record of a research center involved in the development and application of sensor network and wireless technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortative mixing of selected node characteristics, unveiling the researchers' propensity to collaborate preferentially with others with a similar academic profile. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.Comment: Scientometrics (In press

Systematic review and network meta-analysis with individual participant data on cord management at preterm birth (iCOMP): study protocol

Introduction Timing of cord clamping and other cord management strategies may improve outcomes at preterm birth. However, it is unclear whether benefits apply to all preterm subgroups. Previous and current trials compare various policies, including time-based or physiology-based deferred cord clamping, and cord milking. Individual participant data (IPD) enable exploration of different strategies within subgroups. Network meta-analysis (NMA) enables comparison and ranking of all available interventions using a combination of direct and indirect comparisons. Objectives (1) To evaluate the effectiveness of cord management strategies for preterm infants on neonatal mortality and morbidity overall and for different participant characteristics using IPD meta-analysis. (2) To evaluate and rank the effect of different cord management strategies for preterm births on mortality and other key outcomes using NMA. Methods and analysis Systematic searches of Medline, Embase, clinical trial registries, and other sources for all ongoing and completed randomised controlled trials comparing cord management strategies at preterm birth (before 37 weeks’ gestation) have been completed up to 13 February 2019, but will be updated regularly to include additional trials. IPD will be sought for all trials; aggregate summary data will be included where IPD are unavailable. First, deferred clamping and cord milking will be compared with immediate clamping in pairwise IPD meta-analyses. The primary outcome will be death prior to hospital discharge. Effect differences will be explored for prespecified participant subgroups. Second, all identified cord management strategies will be compared and ranked in an IPD NMA for the primary outcome and the key secondary outcomes. Treatment effect differences by participant characteristics will be identified. Inconsistency and heterogeneity will be explored. Ethics and dissemination Ethics approval for this project has been granted by the University of Sydney Human Research Ethics Committee (2018/886). Results will be relevant to clinicians, guideline developers and policy-makers, and will be disseminated via publications, presentations and media releases

Measuring co-authorship and networking-adjusted scientific impact

Appraisal of the scientific impact of researchers, teams and institutions with productivity and citation metrics has major repercussions. Funding and promotion of individuals and survival of teams and institutions depend on publications and citations. In this competitive environment, the number of authors per paper is increasing and apparently some co-authors don't satisfy authorship criteria. Listing of individual contributions is still sporadic and also open to manipulation. Metrics are needed to measure the networking intensity for a single scientist or group of scientists accounting for patterns of co-authorship. Here, I define I1 for a single scientist as the number of authors who appear in at least I1 papers of the specific scientist. For a group of scientists or institution, In is defined as the number of authors who appear in at least In papers that bear the affiliation of the group or institution. I1 depends on the number of papers authored Np. The power exponent R of the relationship between I1 and Np categorizes scientists as solitary (R>2.5), nuclear (R=2.25-2.5), networked (R=2-2.25), extensively networked (R=1.75-2) or collaborators (R<1.75). R may be used to adjust for co-authorship networking the citation impact of a scientist. In similarly provides a simple measure of the effective networking size to adjust the citation impact of groups or institutions. Empirical data are provided for single scientists and institutions for the proposed metrics. Cautious adoption of adjustments for co-authorship and networking in scientific appraisals may offer incentives for more accountable co-authorship behaviour in published articles.Comment: 25 pages, 5 figure

A polymorphism in the gene encoding carnosinase (CNDP1) as a predictor of mortality and progression from nephropathy to end-stage renal disease in type 1 diabetes mellitus

Aims/hypothesis Homozygosity for a five leucine repeat (5L-5L) in the carnosinase gene (CNDP1) has been found to be cross-sectionally associated with a low frequency of diabetic nephropathy (DN), mainly in type 2 diabetes. We prospectively investigated in patients with type I diabetes whether: (1) 5L-5L is associated with mortality; (2) there is an interaction of 5L-5L with DN or sex for prediction of mortality; and (3) 5L-5L is associated with progression to end-stage renal disease (ESRD). Methods In this prospective study in white European patients with type 1 diabetes, individuals with DN were defined by persistent albuminuria >= 300 mg/24 h. Controls without nephropathy were defined by persistent (>15 years) normoalbuminuria Results The study involved 916 patients with DN and 1,170 controls. During follow-up for 8.8 years, 107 patients (14%) with 5L-5L died compared with 182 patients (13.8%) with other genotypes (p=0.99). There was no significant interaction of 5L-5L with DN for prediction of mortality (p=0.57), but a trend towards interaction with sex (p=0.08). In patients with DN, HR for ESRD in 5L-5L vs other genotypes was not constant over time, with increased risk for 5L-5L beyond 8 years of follow-up (p=0.03). Conclusions/interpretation CNDP1 polymorphism was not associated with mortality, and nor was there an interaction of this polymorphism with DN for prediction of mortality in patients with type 1 diabetes. CNDP1 polymorphism predicts progression to ESRD in patients with DN, but only late after baseline measurements

Is Lactoferrin More Effective in Reducing Late-Onset Sepsis in Preterm Neonates Fed Formula Than in Those Receiving Mother&apos;s Own Milk? Secondary Analyses of Two Multicenter Randomized Controlled Trials

Background: Lactoferrin is the major antimicrobial protein in human milk. In our randomized controlled trial (RCT) of bovine lactoferrin (BLF) supplementation in preterm neonates, BLF reduced late-onset sepsis (LOS). Mother's own milk (MM) contains higher concentrations of lactoferrin than donor milk or formula, but whether BLF is more effective in infants who receive formula or donor milk is uncertain. Aim: To evaluate the incidence of LOS in preterm infants fed MM and in those fed formula and/or donor milk. Study Design: This is a (A) post hoc subgroup analysis, in our RCT of BLF, of its effects in preterm infants fed MM, with or without formula, versus those fed formula and/or donor milk (no-MM) and (B) post hoc meta-analysis, in our RCT of BLF and in the ELFIN (Enteral Lactoferrin in Neonates) RCT, of the effect of BLF in subgroups not exclusively fed MM. Results (A) Of 472 infants in our RCT, 168 were randomized to placebo and 304 were randomized to BLF. Among MM infants, LOS occurred in 22/133 (16.5%) infants randomized to placebo and in 14/250 (5.6%) randomized to BLF (relative risk or risk ratio (RR): 0.34; relative risk reduction (RRR): 0.66; 95% confidence interval (95% CI) for RR: 0.18-0.64; p &lt; 0.0008). Among no-MM infants, LOS occurred in 7/35 (20.0%) randomized to placebo and in 2/54 (3.7%) randomized to BLF (RR: 0.19; RRR: 0.81; 95% CI for RR: 0.16-0.96; p = 0.026). In multivariable logistic regression analysis, there was no interaction between BLF treatment effect and type of feeding (p = 0.628). (B) In 1,891 infants not exclusively fed MM in our RCT of BLF and in the ELFIN RCT, BLF reduced the RR of LOS by 18% (RR: 0.82; 95% CI: 0.71-0.96; p = 0.01). Conclusion: Adequately powered studies should address the hypothesis that BLF is more effective in infants fed formula or donor milk than those fed MM. Such studies should evaluate whether a specific threshold of total lactoferrin intake can be identified to protect such patients from LOS

The CTGF -945GC polymorphism is not associated with plasma CTGF and does not predict nephropathy or outcome in type 1 diabetes

The -945GC polymorphism (rs6918698) in the connective tissue growth factor gene promoter (CTGF/CCN-2) has been associated with end organ damage in systemic sclerosis. Because CTGF is important in progression of diabetic kidney disease, we investigated whether the -945GC polymorphism is associated with plasma CTGF level and outcome in type 1 diabetes