Sprint running: how changes in step frequency affect running mechanics and leg spring behaviour at maximal speed

The purpose of this study was to investigate the changes in selected biomechanical variables in 80-m maximal sprint runs while imposing changes in step frequency (SF) and to investigate if these adaptations differ based on gender and training level. A total of 40 athletes (10 elite men and 10 women, 10 intermediate men and 10 women) participated in this study; they were requested to perform 5 trials at maximal running speed (RS): at the self-selected frequency (SF_s) and at SF ±15% and ±30%SF_s. Contact time (CT) and flight time (FT) as well as step length (SL) decreased with increasing SF, while k_vert increased with it. At SF_s, k_leg was the lowest (a 20% decrease at ±30%SF_s), while RS was the largest (a 12% decrease at ±30%SF_s). Only small changes (1.5%) in maximal vertical force (F_max) were observed as a function of SF, but maximum leg spring compression (ΔL) was largest at SF_s and decreased by about 25% at ±30%SF_s. Significant differences in F_max, Δy, k_leg and k_vert were observed as a function of skill and gender (P < 0.001). Our results indicate that RS is optimised at SF_s and that, while k_vert follows the changes in SF, k_leg is lowest at SF_s.     

Haemoglobin A1c-based screening for prediabetes and diabetes mellitus: a multi-center study in Croatian adult population

IntroductionBased on the hypothesis that there is a substantial rate of adults with prediabetes and undiagnosed diabetes mellitus (DM), our aim was to perform haemoglobin A1c (HbA_1c)-based screening in a cohort of Croatian adults and estimate the prevalence of prediabetes and undiagnosed DM according to American Diabetes Association criteria.Materials and methodsThis multi-center, cross-sectional study performed in six Croatian hospitals included 5527 patients aged 40 to 70 years admitted to the Emergency Department or undergoing a primary care check-up. Haemoglobin A1c was measured from leftover whole blood samples using the enzymatic method on either Alinity c or Architect c-series analyser (Abbott Laboratories, Chicago, USA). Haemoglobin A1c between 39-47 mmol/mol was classified as prediabetes, while ≥ 48 mmol/mol as undiagnosed DM.ResultsAfter exclusion of 435 patients with known DM, the final cohort included 5092 patients (median age 57; 56% males). A total of 882 (17.3%) patients had HbA_1c values between 39 and 47 mmol/mol. There were 214 (4.2%) patients with HbA_1c ≥ 48 mmol/mol. Prediabetes prevalence ranged from 14.2% to 20.5%, while undiagnosed DM from 3.3% to 7.3%, with statistically significant differences among settings (P < 0.001). Age-stratified analysis showed that prediabetes and undiagnosed DM prevalence increase with age (P < 0.001), being 25.4% and 5.8%, respectively, in patients aged 60 to 70 years.ConclusionUnderlying impairment of glucose metabolism was identified in about one in five adults, with significant number of patients with already overt DM. These results should serve as a starting point for further steps directed towards promotion of preventive measures for DM in Croatia.     

Comparison of diagnostic accuracy for eight SARS-CoV-2 serological assays

IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus.Materials and methodsThe comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)-negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA).ResultsAgreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001).ConclusionThere is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.     

An integrated and automated segmentation approach to deteriorated regions recognition on 3D reality-based models of cultural heritage artifacts

In the field of Cultural Heritage, image analysis represents an indispensable practice for restorers to collect information about the state of preservation of monuments and artifacts and plan restoration interventions. In addition, during the last two decades, the wide spread of remote sensing technologies and the possibility to build 3D reality-based models of artifacts allow the extension of image analysis to 3D environments. In this context, the purpose of this contribution is to show the results of investigations held in order to provide a methodology for the automatic detection of deteriorated areas within architectures and artifacts using colour images as a field of examination. Using both 2D and 3D segmentation approaches, our methodology aims at speeding and efficiently performing the automatic detection of deteriorated zones within Cultural Heritage and therefore segment 3D digital models acquired using different survey technologies. Within our investigations, we selected case studies concerning recurrent deteriorations, such as, for example, detachments, cracks and chromatic alterations; we run them both to manual and to automatic recognition and selection tests, in order to compare the results obtained using these approaches and evaluate the reliability of the automatic one. Results comparison included computational and user time, quantification of the deteriorated area error between manual and automatically detected zones. Additional parameters characterizing the specific type of deteriorations were also computed for each case study. Comparison between the automatic and the manual procedure showed that the automatic detection is faster and reliable in all our selected case studies, with evident improvements in the efficient evaluation of the entity and extension of deteriorated areas on 3D geometry.     

Academic engagement: A review of the literature 2011-2019

We provide a systematic review of the literature on academic engagement from 2011 onwards, which was the cut-off year of a previous review article published in Research Policy. Academic engagement refers to knowledge-related interactions of academic scientists with external organisations. It includes activities such as collaborative research with industry, contract research, consulting and informal ties. We consolidate what is known about the individual, organisational and institutional antecedents of academic engagement, and its consequences for research, commercialisation, and society at large. Our results suggest that individual characteristics associated with academic engagement include being scientifically productive, senior, male, locally trained, and commercially experienced. Academic engagement is also socially conditioned by peer effects and disciplinary characteristics. In terms of consequences, academic engagement is positively associated with academics’ subsequent scientific productivity. We propose new areas of investigation where evidence remains inconclusive, including individual life cycle effects, the role of organisational contexts and incentives, cross-national comparisons, and the impact of academic engagement on the quality of subsequent research as well as the educational, commercial and society-wide impact.     

Applicability assessment of Semantic Web technologies

The Semantic Web is one of the fastest developing fields within the Information and Communication Technology sector and, as such, under constant examination by scientists and IT professionals. This article aims to provide a better understanding of the applicability of Semantic Web tools and technologies in practice. This aim will be achieved by surveying the recommended and emerging W3C standards, presenting an overview of the state-of-the-art in the Semantic Web research in the European Union, analysing the W3C collection of Case studies and Use Cases, and discussing the extent of adoption of Semantic Web technologies. The overall technology maturity level assessment has shown that Semantic Web technologies are finding their ways into real-world applications, and that, rather than being merely a fashionable research issue, the Semantic Web, slowly but surely, becomes our reality.     

Apples and oranges: Educational enrollment and attainment across countries in Latin America and the Caribbean

This paper uses household survey data to rank LAC countries’ performance in two areas: (i) getting children into school on time and keeping them there, and (ii) turning their contact with the educational system into years of schooling. It presents multiple rankings because most countries’ performance is not uniform across these dimensions. For instance, the Dominican Republic performs almost as well as the richest countries when it comes to keeping children in school, but as badly as the poorest few in terms of turning attendance into years of schooling. Further, the rankings, which are based on conventional and new measures of educational systems’ performance, are occasionally quite different from those obtained using more widely available administrative data.     

The effects of two different correction strategies on the snatch technique in weightlifting

Improving motor skills represents one of the major issues in motor control and motor learning literature. The aim of this study was to investigate which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction of the snatch technique. Thirty well-trained male weightlifters were randomly assigned to one of three training conditions (MAE, DI and Control). The experiment took place in only one practice session in which each lifter performed 3 pretraining trials, 8 training intervention trials, and 3 post-training trials, and a retention test session after 1 week. An optoelectronic motion capture system was used to measure the kinematic parameters of the weightlifting performance. After the training intervention, data showed that the MAE group revealed a greater improvement in several kinematic parameters when compared to the DI and Control groups, and the benefits derived from its application were still present 1 week later in the retention test. Nevertheless, the findings of the present study should be interpreted with caution due to the relatively small sample size; further research will also be necessary to evaluate the effects of MAE with different ability levels and other sport skills. The present findings could have practical implications for sport psychology and physical education because while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners’ motivation and sport enjoyment.