Self-complexification through integral feedback in eusocial paper wasps of various levels of sociality.

We investigate how simple physical interactions can generate remarkable diversity in the life history of social agents using data of social wasps, yielding complex scalable task partitioning. We built and analyzed a computational model to investigate how diverse task allocation patterns found in nature can emerge from the same behavioral blueprint. Self-organizing mechanisms of interwoven behavioral feedback loops, task-dependent time delays and simple material flows between interacting individuals yield an emergent homeostatic self-regulation while keeping the global colony performance scalable.

Physical exercise induces mental flow related to catecholamine levels in noncompetitive, but not competitive conditions in men.

The study aimed to reveal physical exercise conditions and catecholamine response-dependent differences while an individual experiences a flow state (FS) following noncompetitive and competitive running drills. Urine laboratory catecholamine levels were measured using a standard clinical method during pre- and post-physical exercises. The noncompetitive task involved intermittent running drills, from an absolute beginning up through exhaustion.

Reward Dependence-Moderated Noradrenergic and Hormonal Responses During Noncompetitive and Competitive Physical Activities.

The aim of this study was to reveal whether increased reward dependence (RD) plays a role in the catecholamine neurotransmitter release and testosterone hormone regulation during physical activities among healthy trained participants. Twenty-two male participants (mean age: 40.27 ± 5.

Correction: Resilience of honeybee colonies via common stomach: A model of self-regulation of foraging.

[This corrects the article DOI: 10.1371/journal.pone.

Integral feedback control is at the core of task allocation and resilience of insect societies.

Homeostatic self-regulation is a fundamental aspect of open dissipative systems. Integral feedback has been found to be important for homeostatic control on both the cellular and molecular levels of biological organization and in engineered systems. Analyzing the task allocation mechanisms of three insect societies, we identified a model of integral control residing at colony level.

Resilience of honeybee colonies via common stomach: A model of self-regulation of foraging.

We propose a new regulation mechanism based on the idea of the "common stomach" to explain several aspects of the resilience and homeostatic regulation of honeybee colonies. This mechanism exploits shared pools of substances (pollen, nectar, workers, brood) that modulate recruitment, abandonment and allocation patterns at the colony-level and enable bees to perform several survival strategies to cope with difficult circumstances: Lack of proteins leads to reduced feeding of young brood, to early capping of old brood and to regaining of already spent proteins through brood cannibalism. We modeled this system by linear interaction terms and mass-action law.

Task Allocation of Wasps Governed by Common Stomach: A Model Based on Electric Circuits.

Simple regulatory mechanisms based on the idea of the saturable 'common stomach' can control the regulation of construction behavior and colony-level responses to environmental perturbations in Metapolybia wasp societies. We mapped the different task groups to mutual inductance electrical circuits and used Kirchoff's basic voltage laws to build a model that uses master equations from physics, yet is able to provide strong predictions for this complex biological phenomenon. Similar to real colonies, independently of the initial conditions, the system shortly sets into an equilibrium, which provides optimal task allocation for a steady construction, depending on the influx of accessible water.

The Mechanisms of Water Exchange: The Regulatory Roles of Multiple Interactions in Social Wasps.

Evolutionary benefits of task fidelity and improving information acquisition via multiple transfers of materials between individuals in a task partitioned system have been shown before, but in this paper we provide a mechanistic explanation of these phenomena. Using a simple mathematical model describing the individual interactions of the wasps, we explain the functioning of the common stomach, an information center, which governs construction behavior and task change. Our central hypothesis is a symmetry between foragers who deposit water and foragers who withdraw water into and out of the common stomach.

How regulation based on a common stomach leads to economic optimization of honeybee foraging.

Simple regulatory mechanisms based on the idea of the saturable 'common stomach' can control the regulation of protein foraging and protein allocation in honeybee colonies and colony-level responses to environmental changes. To study the economic benefits of pollen and nectar foraging strategies of honeybees to both plants and honeybees under different environmental conditions, a model was developed and analyzed. Reallocation of the foraging workforce according to the quality and availability of resources (an 'adaptive' strategy used by honeybees) is not only a successful strategy for the bees but also for plants, because intensified pollen foraging after rain periods (when nectar quality is low) compensates a major fraction of the pollination flights lost during the rain.

Long-term sub-lethal effects of low concentration commercial herbicide (glyphosate/pelargonic acid) formulation in Bryophyllum pinnatum.

Potential long-term (~7months) sub-lethal impacts of soil-applied low levels of Roundup herbicide formulation were investigated in a greenhouse environment using the vegetative clones of succulent non-crop plant model, Bryophyllum pinnatum (Lam.) Oken. An eleven day LC50 (concentration that killed 50% of the plants) was found to be 6.

Associations Between Attitudes Toward Physical Education and Aerobic Capacity in Hungarian High School Students.

Purpose: The purpose of this study was to create a physical education (PE) attitude scale and examine how it is associated with aerobic capacity (AC).

Method: Participants (n = 961, aged 15-20 years) were randomly selected from 26 Hungarian high schools. AC was estimated from performance on the Progressive Aerobic Cardiovascular and Endurance Run test, and the attitude scale had 31 items measured on a Likert scale that ranged from 1 to 5.

Agreement Between Omron 306 and Biospace InBody 720 Bioelectrical Impedance Analyzers (BIA) in Children and Adolescents.

Purpose: The purpose of this study was to test the convergent validity of Omron 306 using Biospace InBody 720.

Method: A total of 267 participants (145 boys; aged 10.4-17.

Overview of the Hungarian National Youth Fitness Study.

The 2012 Public Act on Education in Hungary made daily physical education (PE) a mandatory part of the school day starting in the 2012-2013 school year. This directive was linked to a significant reorganization of the Hungarian education system including a new National Core Curriculum that regulates the objectives and contents of PE. The Hungarian School Sport Federation (HSSF) recognized the opportunity and created the Strategic Actions for Health-Enhancing Physical Education or Testnevelés az Egészségfejlesztésben Stratégiai Intézkedések (TESI) project.

Establishing Normative Reference Values for Handgrip Among Hungarian Youth.

Purpose: The purpose of this study was to examine age- and sex-related variation in handgrip strength and to determine reference values for the Hungarian population.

Method: A sample of 1,086 Hungary youth (aged 11-18 years old; 654 boys and 432 girls) completed a handgrip strength assessment using a handheld dynamometer. Quantile regression was used to compute separate models for boys and girls and included a linear, cubic, and quadratic term for age to account for nonlinear patterns.

Cross-Validation of FITNESSGRAM® Health-Related Fitness Standards in Hungarian Youth.

Purpose: The purpose of this study was to cross-validate FITNESSGRAM® aerobic and body composition standards in a representative sample of Hungarian youth.

Method: A nationally representative sample (N = 405) of Hungarian adolescents from the Hungarian National Youth Fitness Study (ages 12-18.9 years) participated in an aerobic capacity assessment via treadmill test to maximum to determine peak oxygen consumption (VO2peak) and a bioelectrical impedance assessment to estimate percent body fat (%BF).

Sting, Carry and Stock: How Corpse Availability Can Regulate De-Centralized Task Allocation in a Ponerine Ant Colony.

We develop a model to produce plausible patterns of task partitioning in the ponerine ant Ectatomma ruidum based on the availability of living prey and prey corpses. The model is based on the organizational capabilities of a "common stomach" through which the colony utilizes the availability of a natural (food) substance as a major communication channel to regulate the income and expenditure of the very same substance. This communication channel has also a central role in regulating task partitioning of collective hunting behavior in a supply&demand-driven manner.

Neuromuscular fatigue during 200 m breaststroke.

i) to analyze activation patterns of four upper limb muscles (duration of the active and non-active phase) in each lap of 200m breaststroke, ii) quantify neuromuscular fatigue, with kinematics and physiologic assessment. Surface electromyogram was collected for the biceps brachii, deltoid anterior, pectoralis major and triceps brachii of nine male swimmers performing a maximal 200m breaststroke trial. Swimming speed, SL, SR, SI decreased from the 1(st) to the 3(rd) lap.

Short-term high intensity plyometric training program improves strength, power and agility in male soccer players.

The aim of the present study was to investigate the effects of a short-term in-season plyometric training program on power, agility and knee extensor strength. Male soccer players from a third league team were assigned into an experimental and a control group. The experimental group, beside its regular soccer training sessions, performed a periodized plyometric training program for six weeks.

Time delay implies cost on task switching: a model to investigate the efficiency of task partitioning.

Task allocation, and task switching have an important effect on the efficiency of distributed, locally controlled systems such as social insect colonies. Both efficiency and workload distribution are global features of the system which are not directly accessible to workers and can only be sampled locally by an individual in a distributed system. To investigate how the cost of task switching affects global performance we use social wasp societies as a metaphor to construct a simple model system with four interconnected tasks.

Regulation of task differentiation in wasp societies: a bottom-up model of the "common stomach".

Metapolybia wasps live in small societies (around one hundred adults) and rear their young in nests they construct on flat surfaces from plant materials. For processing nest paper, they must gather plant materials and process it into pulp with water. The water is collected by water foragers and is transferred to pulp foragers indirectly via a "common stomach.

Mentoring interdisciplinary undergraduate students via a team effort.

We describe how a team approach that we developed as a mentoring strategy can be used to recruit, advance, and guide students to be more interested in the interdisciplinary field of mathematical biology, and lead to success in undergraduate research in this field. Students are introduced to research in their first semester via lab rotations. Their participation in the research of four faculty members-two from biology and two from mathematics-gives them a first-hand overview of research in quantitative biology and also some initial experience in research itself.

Force production and spatial arm coordination profile in arm crawl swimming in a fixed position.

This study analyzed the relationship between mechanical force production and spatial arm position of the swimming movement for each side of the swimmer. Eight internationally recognized male swimmers performed fix positioned arm only swimming with a dynamometer synchronized with underwater cameras. The upper arm positions (α in side, β in frontal view) and the elbow angles (γ in 3D) were determined at the moment where the force production reached the peak (Fmax) and the maximal values of rate of force development (RFDmax).

Teacher, peer and parent autonomy support in physical education and leisure-time physical activity: A trans-contextual model of motivation in four nations.

An extended trans-contextual model of motivation for health-related physical activity was tested in samples from four nations. The model proposes a motivational sequence in which perceived autonomy support from teachers in a physical education (PE) context and from peers and parents in a leisure-time physical activity context predict autonomous motivation, intentions and physical activity behaviour in a leisure-time context. A three-wave prospective correlational design was employed.

Emotional intelligence and emotions associated with optimal and dysfunctional athletic performance.

This study investigated relationships between self-report measures of emotional intelligence and memories of pre-competitive emotions before optimal and dysfunctional athletic performance. Participant-athletes (n = 284) completed a self-report measure of emotional intelligence and two measures of pre-competitive emotions; a) emotions experienced before an optimal performance, and b) emotions experienced before a dysfunctional performance. Consistent with theoretical predictions, repeated MANOVA results demonstrated pleasant emotions associated with optimal performance and unpleasant emotions associated with dysfunctional performance.