Optimizing speed and agility in a volleyball game – Junior players

The present study aims to identify if and how motor skills such as speed and agility can be improved by using training activities corresponding to performance in volleyball. The experiment included a total of 16 male athletes (17–18 years old), divided into two groups (control and experimental group). The tests applied in the research were the Illinois test and the Hexagon test, since speed, agility and quickness are essential to high performance in volleyball. After the initial tests, the experimental group became part of a 6-week training programme, designed to learn and master speed and agility drills. The results obtained at the final control tests demonstrated that the indicators of motor skills registered a real progress. This confirmed our working hypothesis stating that physical exercises, motor games and other means, specific to the game of volleyball, can influence the development of motor skills. Keywords: Agility, speed, performance sport, Illinois test, Hexagon test, volleyball training.

US-Russian arms talks aim for slow but real progress

Headline US/RUSSIA: Arms talks aim for slow but real progress

Progress outside of paradise: Old and new comparative approaches to contentious politics

Descriptive or ethnographic studies were once the stock-in-trade of the comparative politics of non-Western areas and illiberal states. The last few decades have seen a dramatic growth in quantitative—or at least systematic—studies of these systems. This marks real progress, but, in the process, some of the advantages of ethnographic and “unit-contextual” studies have been lost. The contributors to this symposium have used ethnographic methods—often in combination with other methods—to examine and compare episodes of contentious politics in a number of these countries. Drawing on some of the “classics” of comparative politics, this article emphasizes both the continuities and the departures of the new generation of “ethnography plus” research efforts represented in this symposium.

How Far Have We Progressed in Identifying Self-admitted Technical Debts? A Comprehensive Empirical Study

Background. Self-admitted technical debt (SATD) is a special kind of technical debt that is intentionally introduced and remarked by code comments. Those technical debts reduce the quality of software and increase the cost of subsequent software maintenance. Therefore, it is necessary to find out and resolve these debts in time. Recently, many automatic approaches have been proposed to identify SATD. Problem. Popular IDEs support a number of predefined task annotation tags for indicating SATD in comments, which have been used in many projects. However, such clear prior knowledge is neglected by existing SATD identification approaches when identifying SATD. Objective. We aim to investigate how far we have really progressed in the field of SATD identification by comparing existing approaches with a simple approach that leverages the predefined task tags to identify SATD. Method. We first propose a simple heuristic approach that fuzzily Matches task Annotation Tags ( MAT ) in comments to identify SATD. In nature, MAT is an unsupervised approach, which does not need any data to train a prediction model and has a good understandability. Then, we examine the real progress in SATD identification by comparing MAT against existing approaches. Result. The experimental results reveal that: (1) MAT has a similar or even superior performance for SATD identification compared with existing approaches, regardless of whether non-effort-aware or effort-aware evaluation indicators are considered; (2) the SATDs (or non-SATDs) correctly identified by existing approaches are highly overlapped with those identified by MAT ; and (3) supervised approaches misclassify many SATDs marked with task tags as non-SATDs, which can be easily corrected by their combinations with MAT . Conclusion. It appears that the problem of SATD identification has been (unintentionally) complicated by our community, i.e., the real progress in SATD comments identification is not being achieved as it might have been envisaged. We hence suggest that, when many task tags are used in the comments of a target project, future SATD identification studies should use MAT as an easy-to-implement baseline to demonstrate the usefulness of any newly proposed approach.

Germany’s Energiewende at a Crossroads

This article examines Germany’s current climate and energy policies. Nearly two decades on, Germany’s Energiewende—the transition to a less carbonintensive economy—is at a crossroads. While remarkable advances have been made, the technical difficulties of expanding the energy transition beyond the electricity sector, the mounting costs of the transition itself, and now the covid-19 pandemic are slowing further progress. Maintaining the momentum of the Energiewende would require collaborative action, yet the principal political players have different agendas, making it difficult to reach decisions. In this article, we consider three of those actors: the German public, the opposition parties, and the government. We find that agreements on German climate policy have been diluted in political compromises and that real progress is being blocked. These problems will only increase as Germany deals with the consequences of the pandemic and faces a transition in national leadership in 2021.

Bioactivity—Symphony or Cacophony? A Personal View of a Tangled Field

In the pursuit of better treatments, the concept of a chemically-active material, responding to local conditions by causing reactions, or reacting to produce substances that are deemed beneficial, seems laudable. Ultimately, the goal appears to be to recruit natural biological processes such that a natural ‘repair’ is effected. This goal seems to be the reason for prefixing “bio-” to many terms with a view to advertising the desire, yet without presenting evidence that it has occurred, or indeed that it is capable of occurring, relying instead on non-biological processes to justify the claims. The dogma is such that all work where local ‘responsive’ chemistry is involved must receive the label “bioactive” to legitimize and promote. Nevertheless, the primary evidence adduced is flawed, and the claim must fail. A rethink to restore scientific sense and confidence in the endeavour is essential if real progress is to be made.

Bioactivity – Symphony or Cacophony?

In the pursuit of better treatments, the concept of a chemically-active material, responding to local conditions by causing reactions, or reacting to produce substances that are deemed beneficial, seems laudable. Ultimately, the goal appears to be to recruit natural biological processes such that a natural ‘repair’ is effected. This goal seems to be the reason for prefixing “bio-“ to many terms with a view to advertising the desire, yet without presenting evidence that it has occurred, or indeed that it is capable of occurring, relying instead on non-biological processes to justify the claims. The dogma is such that all work where local ‘responsive’ chemistry is involved must receive the label “bioactive” to legitimize and promote. Nevertheless, the primary evidence adduced is flawed, and the claim must fail. A rethink to restore scientific sense and confidence in the endeavour is essential if real progress is to be made.