bluuebunny/crossref_metadata_2025 huggingface dataset:
Age effect v juniorskom tenise
Authors: Agricola Adrián , Zháněl Jiří , Hubáček Ondřej , Zvonař Martin , Psalman Vladimír
Published: February 2018

The first publications about the theory of the age effect (theory of the influence of age) appeared in sports science in the 80´s of the last century. Though it was not as long as the last few years we have encountered with a research of this particular topic more regularly. The theory is based on the assumption that the athletes born at the beginning of the calendar year are, mainly in the junior age, more successful than later born athletes. This has been shown in many studies especially in ice hockey, soccer, tennis but also in other sports. This theme hasn´t been revealed in Czech kinanthropology yet, in priciple of which we aim to present using carried out on the elite junior female players. The purpose of this study was to verify the influence of the age effect on the participants of the World Junior Tennis Finals (WJTF - tennis teams Championships U14) from 2007 to 2011.
Psychomotorika a sebeobrana jako účinná pohybová intervence ovlivňující výkonovou motivaci jedinců se sluchovým postižením
Authors: Dlouhý Martin , Dlouhá Jana , Slezáček Milan , Kuhnová Věra
Published: February 2018

The article deals with the development of achievement motivation of young people with hearing impairment during adolescence through a special intervention program. The aim was to influence the sport specific movement program the achievement motivation of the youth with hearing disabilities.The methodology of the work he was elected a basic empirical approach using a simple experiment. The main factor was the experimental intervention movement program that consisted of the foundations of basic self-defense and psychomotor. The main research method was the aspiration test (Bakalář, 1987). Hypotheses that the effects of the intervention program will increase the level of achievement motivation in the experimental group of young people with hearing disabilities was confirmed. Research confirmed the assumption that the fundamentals of self defense and psychomotor have a significant influence on the development of achievement motivation of the selected group of young people with hearing impairments. This article is part of the sub successfully defended his dissertation on FSpS MU in Brno.
Analýza reakčně-rychlostních schopností u rekreačních hráčů badmintonu (pilotní výzkum)
Authors: Pechová Lenka , Korvas Pavel
Published: February 2018

The main goal of the pilot research was to do an introductory analysis of the changes of the quick reaction abilities of the recreational badminton players which have a different level of the efficiency during the training cycle.There was made an intervention programme which lasted 3 months. In this programme participated an experimental team formed exclusively of recreational badminton players. The Filtro reaction check was used for diagnostics. After completing the intervention programme the results were compared with a testing team which consists exclusively of reacreational players as well and whose members didn´t participate in the intervention programme.The results have shown the differencies between the experimental team in which the impovement was 12,6 % as for men and 14,2 % as for women and the testing team in which as for men the improvement wasn´t significant and the women´s results got worse. The results were compared for statistical significance level of 0,05. While the data collecting is still in progress, the partial results indicates that it is possible to improve the level of the quick reaction abilities of adult recreatinal badminton players in a relatively short training cycle.
Kvalita aktívnej hmoty a segmentálna distribúcia tekutín v tele ako predpoklad výkonu u elitných basketbalistiek
Authors: Malá Lucia , Malý Tomáš , Zahálka František , Teplan Jaroslav , Kaplan Aleš
Published: February 2018

The article presents active mass quality (fat free mass, muscle mass) and segmental distribution of body fluids as a prerequisite of performance in elite female basketball players, silvermedallists at 2010 World Championship. The collected data indicated the level of fat free mass (60.96±5.35 kg) and muscle mass (57.07±5.0 kg) at the level of elite athletes. Fat mass showed lower percentage proportion than it is presented by available literature (14.34±2.37 %). Based on the gained data, it is not possible to definitely express a trend in proportion for individual playing positions. Segmental distribution of body fluids revealed a symmetry in favour of a dominant upper limb (p < 0.01), whichindicatetheneed to perform exercises in order to compensate the detected bilateral deficit. In conclusion, the authors discuss the necessity of continual monitoring changes in body composition quality in terms of monitoring individual components of water or directly and indirectly measurable parameters in bioimpedance measurement, respectively.
Spektrum didaktických řídicích stylů ve výuce tělesné výchovy na 2. stupni základní školy
Authors: Sliacky Jiří , Janíková Marcela
Published: February 2018

In the paper, results are presented of empirical research on teaching styles used in physical education lessons in lower-secondary schools, which aimed to analyse everyday instruction and show which teaching styles are used. The method of video study was employed to generate data, which were later coded by means of a system of categories. The findings show that in the analysed lessons, the teachers only used the “command” and the “practice” styles. These findings are discussed in the context of further analysis of the research results and also in the context of other research carried out outside of the Czech Republic.
Psychosociální aspekty rizikového chování sportujících dětí
Authors: Slepička Pavel , Mudrák Jiří
Published: February 2018

In present overview study, we focus on some possible risk factors in child and youth sport. In the overview of contemporary research focusing on doping, violence and fair play, we show how the norms of contemporary competitive sport emphasizing results, maximal performance and victory at all cost may support risk behavior in sporting children and youth, such as doping abuse, inappropriate aggression, or breaking rules and fair play. It seems that this risk behavior is not limited only to the context of sport but translates also in the life outside sport.
Jak ve sportu pomáhá představivost?
Authors: Kavková Veronika , Malůš Marek , Taušová Jitka , Válková Hana
Published: February 2018

This paper deals with the possibilities of using imagery (imagination) in sports to improve performance by psychological means. This mental technique is often used by athletes to improve their sports performance. It is also used as an intervention technique by sports psychologists and more recently coaches for athletes. Abroad, the Training schedule of imagery in sports psychology training is widely developed. The numbers of researchers dealing with the technique of imagery in sport psychology is rising. The essence is to create a mental image of highest quality, and a vivid picture of successful execution of what we want to improve in our performance. This paper deals with the theoretical aspects of the imagery, its characteristics, structure and detailed aspects of the use in sports.
Aplikované pohybové aktivity v mezinárodním kontextu
Authors: Kudláček Martin
Published: February 2018

Adapted physical activity is a profession focused on providing services to persons with special needs (also those with disabilities) and an academic discipline, which supports acceptance of differences and promotes services and inclusion of persons with disabilities. Adapted physical activity includes above all, physical education, sport, recreation and rehabilitation of persons with disabilities. The purpose of this presentation is to describe basic historical and conceptual position of APA in kinesiology in world, Europe and the Czech Republic. IN the presentation we will focus on following topics: (a) world history of scientific organization IFAPA, EUFAPA and selected national organizations (e. g. PTN-AAF, SNAFA, ČAAPA, NCPERID), (b) scientific conferences and journals, (c) Framework of knowledge and competencies with the focus on APA (projects APENS and EUSAPA), and (d) study programs in the USA, EU and the Czech Republic.
Nabídka a organizace pohybových aktivit u dětí a dospělých se specifickými potřebami ve městě Jyväskylä, Finsko
Authors: Pátek Aleš
Published: February 2018

During the four-months internship, I had the opportunity to gain experience in the sport department of Jyväskylä. This department like in the cities in Czech Republic provides sports activities for citizens and takes care of sport facilities in Jyväskylä. The department is responsible for applied physical activities and health enhancing activities for citizens of all ages and physical capability (children, seniors, disabled people and people with chronical illnesses) and also for people at risk of social exclusion (the unemployed, immigrants). The department employs 20 instructors, 30 peer instructors and 80 part time instructors, who organize the activities for citizens. The system has been operating for more than thirty years and the city of Jyväskylä is a pioneer in this field in Finland. The range of activities includes not only activities in the water, gym and in the playground, but also outdoors, on the snow or on ice. For the unemployed and disabled people there is most of the activities for free and seniors and children have discounts.
Srovnání alternativních pohybových aktivit a her u osob se specifickými nároky v ČR a zahraničí
Authors: Trávníková Dagmar
Published: February 2018

The paper presents various approaches in the field of alternative physical activities in people with special needs based on cooperation of the Faculty of Sports Studies and other institutions dealing with this topic. Within the CZ.1.07/2.4.00/17.0037 project various short-term stays, seminars and consultations between academics and students of the FSpS and the cooperating institutions take place, the main goal of which is to compare the concepts of physical activities in different types of handicaps or special needs and their subsequent introduction into practice in the particular institutions. Both academics and students thus have opportunity to gain new experience and skills from various fields of alternative physical activities such as dramatic activities in the Deaf, Halliwick swimming concept, juggling and psychomotor games, psychomotor therapy, use of compensation tools etc.
Projekt Krtek v síti
Authors: Vyhlídal Tomáš , Holická Kateřina , Ješina Ondřej
Published: February 2018

The allowance introduces the lay and professional public project The mole in the network. This project aims at support the comprehensive care of children with oncological disease, their siblings and parents. The chief aim of the project is to create networks of organizations at the level of nonprofit organizations, educational and health organizations and universities that deal with improving the quality of life of children with oncological disease during and after treatment. It will be created a system of cooperation at the level of Endowment fund pediatric Oncology KRTEK (Czech Republic), Palacky University in Olomouc (Czech Republic) and the Regional youth council of Žilina (Slovak Republic). With the czech-slovak cooperation we want to create an unique system of exchangeable residential programs aimed at adapted physical activity where the children with oncological disease, their parents and siblings from the Czech and Slovak Republic will meet together and attend the programs under professional guidance.
Přístupnost tělesné výchovy pro studenty se specifickými nároky na Masarykově univerzitě
Authors: Zvonek Alexandr
Published: February 2018

As of January 31, 2013, there are 450 special needs students currently studying at Masaryk University. This is the largest number of students with special needs among all Czech universities. These are students with visual, hearing or mobility impairment or other disabilities. As well as others, these students have the right (though the use of the word in this context is disputable) to fully participate in all activities pertaining to their studies, which include Physical Education and sports activities. These rights are not only contained in the general legislature, but they are also embedded in Masaryk University’s internal documents (e. g. Rector’s Directive on the Studies of Persons with Special Needs – Rector’s Directive No. 04/03). A substantial part of the tasks connected with fulfilling these rights (and therefore ensuring accessibility of studies) is provided by Teiresias – the Support Centre for Students with Special Needs at Masaryk University. In the area of Physical Education and sports, this involves providing the conditions for accessibility of standard Physical Education and sports activities and creating alternative solutions if the former proves unsuitable for any reason (technical, methodological etc.). On the average, 37 special needs students a semester have been participating in sports activities (standard or alternative) in recent years; with some of them taking more than one Physical Education course in a semester. Providing accessibility encompasses a number of obstacles; there are personnel issues, issues of material and equipment, accessibility of university buildings or suitable didactic and study materials. Sometimes also intervention into the motivation of special needs students is necessary. The activities of Teiresias are based on internal cooperation with the University Sports Centre of the Faculty of Sports, Masaryk University, and external cooperation with both governmental and non-governmental institutions.
Rozvoj vnitřní motivace ke sportování u dětí školního věku se zaměřením na pozitivní prožitky
Authors: Blažej Adam
Published: February 2018

This article deals with the development of satisfaction and positive feelings and their effect on intrinsic motivation of children participated in physical activities. The author describes some attitudes and methods of trainers which could result to evoke such memories from training session that increases the possibility of creating a positive experience out of it. Which often results into an increase of intrinsic motivation to exercise and need of development in that physical activity. There are several theories about the development of intrinsic motivation and satisfaction of various areas of human being. These are described in detail in the article which includes some examples of their use in sport practice. The article is therefore primarily based on a survey of the theories of other sciences and disciplines (psychology, pedagogy) and their application to kinesiology.
Effect of 6-Month Fascia-Oriented Training on Jump Performance in Elite Female Volleyball Players
Authors: Vychodilová Renáta , Zvonař Martin , Sebera Martin
Published: February 2018

Fascia-oriented training is supposed to enhance physical performance potential. Specifically, the employment of the catapult mechanism, the refinement of the elastic energy storage, remodelling, rehydration and release in fascia tissue are supposed to enable faster and more powerful jump performance. The authors of the present study reviewed that little applied research has been conducted to bring scientific evidence verifying these findings in sports practice. The study was conducted to assess the effect of a 6-month, fascia-oriented training programme, designed in accordance with the principles of the fascia-oriented exercise, on the height of vertical countermovement jump (CMJ) performance in well-trained volleyball players. Sixteen female players (age 17.31 ± 0.98; height 173 ± 5.26; weight 65.25 ± 6.75) competing in the national league were randomly assigned for the training (TG) and control group (CG). TG performed a supervised 25-minute fascia-oriented training twice a week for six months. Measurements were conducted before and after the training intervention; the subjects performed 3 trials of CMJ. The study hypothesized that after the application, the height of CMJ would increase more in TG than in CG. The results show that the height of CMJ in TG increased comparing to CMJ height in CG, though the difference is not statistically significant. The results of the effect size manifest the increase of medium level, by 2.2cm in TG. Thus we conclude that the results of the study indicate that the application of the 6-month, fascia-oriented training aimed to develop the vertical jump performance potential in elite volleyball players is not statistically significantly beneficial.
Correlation Structure of Solar Radio Bursts in Accordance with Solar Activity
Authors: Saifuddin Ahmed Jilani  , Sana Wajih
Published: February 2018

Sun is the nearest star that employs us an opportunity to study the behavior of celestial bodies and their influence on Earth’s atmosphere. This paper investigates the dynamics of Solar Radio Bursts (SRB) with respect to their frequencies type II, type III and Mixed type in accord with Sun Spot Number (SSN) over a span of (1996-2010) base over monthly values. Data from National Oceanic and Atmospheric Administration (NOAA) Space Weather Centre were used in this study. This period covers one full and two partial solar cycles. The ionosphere plays a significant role in radio wave communication, therefore the critical frequency of F2 layer (foF2), Maximum electron density (NmF2) Plasma frequency (fP) and Sudden Ionosphere Disturbance (SID) also been included. In various ionospheres quantifications, solar activity such as SSN and 10.7 cm radio flux were used. However SRB influence being considered as a separate variable has not been investigated. The relationship of SRB with Solar Cycle and a comparative study of the influence of these solar variables on ionosphere F2 layer have investigated. The model equations are developed between those variables that have a significant relationship. These equations may be helpful to forecast perturbations in respect of the solar activity.
Flower visitation by hoverflies (Diptera: Syrphidae) in a temperate plant-pollinator network
Authors: Klecka Jan , Hadrava Jiří , Biella Paolo , Akter Asma
Published: February 2018

Hoverflies (Diptera: Syrphidae) are among the most important pollinators, although they attract less attention than bees. They are usually thought to be rather opportunistic flower visitors, although previous studied demonstrated that they show colour preferences and their nectar feeding is affected by morphological constraints related to flower morphology. Despite the growing appreciation of hoverflies and other non-bee insects as pollinators, there is a lack of community-wide studies of flower visitation by syrphids. The aim of this paper is to provide a detailed analysis of flower visitation patterns in a species rich community of syrphids in a Central European grassland and to evaluate how species traits shape the structure of the plant-hoverfly flower visitation network. We found that different species varied in the level of specialisation, and while some species visited a similar spectre of flowers, others partitioned resources more strongly. There was a consistent difference in both specialisation and flower preferences between three syrphid subfamilies. Eristalinae and Pipizinae were more specialised than Syrphinae. Trait-based analyses showed that relative flower visitation i) increased with plant height, but most strongly in Eristalinae; ii) increased with inflorescence size in small species from all three subfamilies, but was independent of inflorescence size in large species of Eristalinae and Syrphinae; and iii) depended on flower colour, but in a subfamily-specific way. Eristalinae showed the strongest flower colour preferences for white flowers, Pipizinae visited mostly white and yellow flowers, while Syrphinae were less affected by flower colour. Exploration of the structure of the plant-hoverfly flower visitation network showed that the network was both modular and nested. We also found that there were almost no differences in specialisation and relative visitation frequency between males and females. Overall, we showed that flower visitation in syrphids was affected by phylogenetic relatedness, body size of syrphids and several plant traits.
Comprensiones de perdón, reconciliación y justicia en víctimas de desplazamiento forzado en Colombia
Authors: Castrillón-Guerrero Laura , Riveros Fiallo Vanessa , Knudsen María-Luisa , López López Wilson , Correa-Chica Andrea , Castañeda Polanco Juan Gabriel
Published: February 2018

The present study analyzes the concepts of forgiveness, reconciliation and justice, in the context of the Colombian armed conflict, on the part of 68 victims of forced displacement who live in the town of Soacha (Cundinamarca, Colombia). It is based on a qualitative methodology drawn from grounded theory. It found that those victims understood forgiveness to involve a transition from negative to positive emotions, and as a synonym for forgetfulness, while reconciliation was understood as a means to restore broken links. Thus, in the context of an armed conflict, justice (restorative and / or distributive) is a requirement for securing forgiveness and reconciliation. The study also reveals the importance of religious faith in the acceptance of forgiveness and reconciliation by the victims.
Isolating the Meteorological Impact of 21st Century GHG Warming on the Removal and Atmospheric Loading of Anthropogenic Fine Particulate Matter Pollution at Global Scale
Authors: Xu Yangyang , Lamarque Jean‐François
Published: February 2018

Particulate matter with the diameter smaller than 2.5 μm (PM2.5) poses health threats to human population. Regardless of efforts to regulate the pollution sources, it is unclear how climate change caused by greenhouse gases (GHGs) would affect PM2.5 levels. Using century‐long ensemble simulations with Community Earth System Model 1 (CESM1), we show that, if the anthropogenic emissions would remain at the level in the year 2005, the global surface concentration and atmospheric column burden of sulfate, black carbon, and primary organic carbon would still increase by 5%–10% at the end of 21st century (2090–2100) due to global warming alone. The decrease in the wet removal flux of PM2.5, despite an increase in global precipitation, is the primary cause of the increase in the PM2.5 column burden. Regionally over North America and East Asia, a shift of future precipitation toward more frequent heavy events contributes to weakened wet removal fluxes. Our results suggest climate change impact needs to be accounted for to define the future emission standards necessary to meet air quality standard.
Risk, Robustness and Water Resources Planning Under Uncertainty
Authors: Borgomeo Edoardo , Mortazavi‐Naeini Mohammad , Hall Jim W. , Guillod Benoit P.
Published: February 2018

Risk‐based water resources planning is based on the premise that water managers should invest up to the point where the marginal benefit of risk reduction equals the marginal cost of achieving that benefit. However, this cost‐benefit approach may not guarantee robustness under uncertain future conditions, for instance under climatic changes. In this paper, we expand risk‐based decision analysis to explore possible ways of enhancing robustness in engineered water resources systems under different risk attitudes. Risk is measured as the expected annual cost of water use restrictions, while robustness is interpreted in the decision‐theoretic sense as the ability of a water resource system to maintain performance—expressed as a tolerable risk of water use restrictions—under a wide range of possible future conditions. Linking risk attitudes with robustness allows stakeholders to explicitly trade‐off incremental increases in robustness with investment costs for a given level of risk. We illustrate the framework through a case study of London's water supply system using state‐of‐the ‐art regional climate simulations to inform the estimation of risk and robustness.
Global Characteristics of Electromagnetic Ion Cyclotron Waves Deduced From Swarm Satellites
Authors: Kim Hyangpyo , Hwang Junga , Park Jaeheung , Bortnik Jacob , Lee Jaejin
Published: February 2018

It is well known that electromagnetic ion cyclotron (EMIC) waves play an important role in controlling particle dynamics inside the Earth's magnetosphere, especially in the outer radiation belt. In order to understand the results of wave‐particle interactions due to EMIC waves, it is important to know how the waves are distributed and what features they have. In this paper, we present some statistical analyses on the spatial distribution of EMIC waves in the low Earth orbit by using Swarm satellites from December 2013 to June 2017 (~3.5 years) as a function of magnetic local time, magnetic latitude, and magnetic longitude. We also study the wave characteristics such as ellipticity, wave normal angle, peak frequency, and wave power using our automatic wave detection algorithm based on the method of Bortnik et al. (2007, https://doi.org/10.1029/2006JA011900). We also investigate the geomagnetic control of the EMIC waves by comparing with geomagnetic activity represented by Kp and Dst indices. We find that EMIC waves are detected with a peak occurrence rate at midlatitude including subauroral region, dawn sector (3–7 magnetic local time), and linear polarization dominated with an oblique propagating direction to the background magnetic field. In addition, our result shows that the waves have some relation with geomagnetic activity; that is, they occur preferably during the geomagnetic storm's late recovery phase at low Earth orbit.
Thermal Alteration of Pyrite to Pyrrhotite During Earthquakes: New Evidence of Seismic Slip in the Rock Record
Authors: Yang Tao , Dekkers Mark J. , Chen Jianye
Published: February 2018

Seismic slip zones convey important information on earthquake energy dissipation and rupture processes. However, geological records of earthquakes along exhumed faults remain scarce. They can be traced with a variety of methods that establish the frictional heating of seismic slip, although each has certain assets and disadvantages. Here we describe a mineral magnetic method to identify seismic slip along with its peak temperature through examination of magnetic mineral assemblages within a fault zone in deep‐sea sediments cored from the Japan Trench—one of the seismically most active regions around Japan—during the Integrated Ocean Drilling Program Expedition 343, the Japan Trench Fast Drilling Project. Fault zone sediments and adjacent host sediments were analyzed mineral magnetically, supplemented by scanning electron microscope observations with associated energy dispersive X‐ray spectroscopy analyses. The presence of the magnetic mineral pyrrhotite appears to be restricted to three fault zones occurring at ~697, ~720, and ~801 m below sea floor in the frontal prism sediments, while it is absent in the adjacent host sediments. Elevated temperatures and coseismic hot fluids as a consequence of frictional heating during earthquake rupture induced partial reaction of preexisting pyrite to pyrrhotite. The presence of pyrrhotite in combination with pyrite‐to‐pyrrhotite reaction kinetics constrains the peak temperature to between 640 and 800°C. The integrated mineral‐magnetic, microscopic, and kinetic approach adopted here is a useful tool to identify seismic slip along faults without frictional melt and establish the associated maximum temperature.
Quantifying Water and Energy Fluxes Over Different Urban Land Covers in Phoenix, Arizona
Authors: Templeton Nicole P. , Vivoni Enrique R. , Wang Zhi‐Hua , Schreiner‐McGraw Adam P.
Published: February 2018

The impact of urbanization on water and energy fluxes varies according to the characteristics of the urban patch type. Nevertheless, urban flux observations are limited, particularly in arid climates, given the wide variety of land cover present in cities. To help address this need, a mobile eddy covariance tower was deployed at three locations in Phoenix, Arizona, to sample the surface energy balance at a parking lot, a xeric landscaping (irrigated trees with gravel) and a mesic landscaping (irrigated turf grass). These deployments were compared to a stationary eddy covariance tower in a suburban neighborhood. A comparison of the observations revealed key differences between the mobile and reference sites tied to the urban land cover within the measurement footprints. For instance, the net radiation varied substantially among the sites in manners consistent with albedo and shallow soil temperature differences. The partitioning of available energy between sensible and latent heat fluxes was modulated strongly by the presence of outdoor water use, with the irrigated turf grass exhibiting the highest evaporative fraction. At this site, we identified a lack of sensitivity of turbulent flux partitioning to precipitation events, which suggests that frequent outdoor water use removes water limitations in an arid climate, thus leading to mesic conditions. Other urban land covers with less irrigation, however, exhibited sensitivity to the occurrence of precipitation, as expected for an arid climate. As a result, quantifying the frequency and magnitude of outdoor water use is critical for understanding evapotranspiration losses in arid urban areas.
A Numerical Study of Atmospheric Perturbations Induced by Heat From a Wildland Fire: Sensitivity to Vertical Canopy Structure and Heat Source Strength
Authors: Kiefer Michael T. , Zhong Shiyuan , Heilman Warren E. , Charney Joseph J. , Bian Xindi
Published: February 2018

An improved understanding of atmospheric perturbations within and above a forest during a wildland fire has relevance to many aspects of wildland fires including fire spread, smoke transport and dispersion, and tree mortality. In this study, the ARPS‐CANOPY model, a version of the Advanced Regional Prediction System (ARPS) model with a canopy parameterization, is utilized in a series of idealized numerical experiments to investigate the influence of vertical canopy structure on the atmospheric response to a stationary sensible heat flux at the ground (“fire heat flux”), broadly consistent in magnitude with the sensible heat flux from a low‐intensity surface fire. Five vertical canopy structures are combined with five fire heat flux magnitudes to yield a matrix of 25 simulations. Analyses of the fire‐heat‐flux‐perturbed u component of the wind, vertical velocity, kinetic energy, and temperature show that the spatial pattern and magnitude of the perturbations are sensitive to vertical canopy structure. Both vertical velocity and kinetic energy exhibit an increasing trend with increasing fire heat flux that is stronger for cases with some amount of overstory vegetation than cases with exclusively understory vegetation. A weaker trend in cases with exclusively understory vegetation indicates a damping of the atmospheric response to the sensible heat from a surface fire when vegetation is most concentrated near the surface. More generally, the results presented in this study suggest that canopy morphology should be considered when applying the results of a fire‐atmosphere interaction study conducted in one type of forest to other forests with different canopy structures.
Seasonal Dynamics of Dissolved Methane in Lakes of the Mackenzie Delta and the Role of Carbon Substrate Quality
Authors: Cunada C. L. , Lesack L. F. W. , Tank S. E.
Published: February 2018

Dissolved CH4 among lake waters of the Mackenzie River Delta was tracked in 2014 to assess how river‐to‐lake connection times, plus carbon substrate quantity and quality, affects the patterns and dynamics of CH4. An under‐ice survey of 29 lakes, three open‐water surveys of 43 lakes, and weekly surveys of 6 lakes revealed that CH4 among lake‐waters ranged from very high concentrations at the end of winter, with highest concentrations linked to shortest annual river connection times, to considerably lower concentrations as open water progressed, with a limited concentration range among lakes by late summer. Lakes most strongly affected by thermokarst varied irregularly from this pattern and did not have the highest CH4 concentrations. CH4 among lake waters was generally related to measures of carbon substrate quantity, where relations with macrophyte biomass and dissolved organic carbon in lake water were statistically stronger than % organic matter within the lake sediments. CH4 was also directly related to the molecular weight (a[250]:a[365]) of dissolved organic matter at the end of winter, but was inversely related to this measure during open water. Carbon quality per se, after accounting for differences in carbon quantity (macrophyte biomass, dissolved organic carbon concentrations, or organic content of lake sediments), appears to play a significant role in controlling CH4 concentrations among the lake waters, particularly during winter ice cover. Carbon quality in lake sediments and of dissolved organic matter in winter lake waters appears to be as important as thermokarst augmentation of carbon quantity for enhancing methanogenesis in this lake‐rich Arctic system.
Hurricane Impact on Seepage Water in Larga Cave, Puerto Rico
Authors: Vieten Rolf , Warken Sophie , Winter Amos , Schröder‐Ritzrau Andrea , Scholz Denis , Spötl Christoph
Published: February 2018

Hurricane‐induced rainfall over Puerto Rico has characteristic δ18O values which are more negative than local rainfall events. Thus, hurricanes may be recorded in speleothems from Larga cave, Puerto Rico, as characteristic oxygen isotope excursions. Samples of 84 local rainfall events between 2012 and 2013 ranged from −6.2 to +0.3‰, whereas nine rainfall samples belonging to a rainband of hurricane Isaac (23–24 August 2012) ranged from −11.8 to −7.1‰. Cave monitoring covered the hurricane season of 2014 and investigated the impact of hurricane rainfall on drip water chemistry. δ18O values were measured in cumulative monthly rainwater samples above the cave. Inside the cave, δ18O values of instantaneous drip water samples were analyzed and drip rates were recorded at six drip sites. Most effective recharge appears to occur during the wet months (April–May and August–November). δ18O values of instantaneous drip water samples ranged from −3.5 to −2.4‰. In April 2014 and April 2015 some drip sites showed more negative δ18O values than the effective rainfall (−2.9‰), implying an influence of hurricane rainfall reaching the cave via stratified seepage flow months to years after the event. Speleothems from these drip sites in Larga cave have a high potential for paleotempestology studies.
Molecular Genetics of Parkinsonism
Authors: Lesage Suzanne , Brice Alexis
Published: February 2018

Over the past decade, genetic causes of parkinsonism have been elucidated, but they account in most populations, for less than 10% of the cases. Since the discovery of the first gene responsible for Parkinson disease (PD),
SCNA
encoding α‐synuclein, linkage mapping and positional cloning have identified autosomal dominantly or recessively inherited PD‐causing mutations in the genes encoding
parkin
,
PINK1
,
DJ‐1
,
LRRK2
and
ATP13A2
, indicating that PD has a highly heterogeneous aetiology. With the introduction of next‐generation sequencing, rare mutations in
DNAJC6
,
SYNJ1
,
VPS13C
,
VPS35
,
DNAJC13
,
TMEM230
and
CHCHD2
were then discovered to cause inherited parkinsonism. In addition, genetic studies from candidate genes, to unbiased genome‐wide approaches including association and next‐generation sequencing have nominated a number of disease determinants. In this article, we will highlight the current progress and future prospects in the field of PD genetics, since 2010.

Key Concepts

The introduction of next‐generation sequencing technologies associated with exome/genome sequencing has accelerated the discovery of novel causative genes and susceptibility factors in numerous Mendelian disorders.

Integrative approaches combining DNA sequencing with gene expression and methylome data will support and accelerate the identification and functional characterisation of the biological variants and disease genes.

Deep and accurate patient phenotyping is of major importance for the success of gene identification in heterogeneous diseases.

The use of larger and more homogeneous cohorts (endophenotype) will increase the chances of identifying high/intermediate risk variants in whole exome/whole genome sequencing.

Identification of additional PD and parkinsonism‐associated genes will enable further elucidation of the disease mechanisms and the development of disease‐modifying therapeutic strategies.

Meta‐analysis of many genome‐wide association studies improves the power to detect more associations and to investigate the consistency or heterogeneity of these associations across diverse datasets and study populations.
Biomedical Applications of Recombinant Silk‐Based Materials
Authors: Aigner Tamara Bernadette , DeSimone Elise , Scheibel Thomas
Published: February 2018

Silk is mostly known as a luxurious textile, which originates from silkworms first cultivated in China. A deeper look into the variety of silk reveals that it can be used for much more, in nature and by humanity. For medical purposes, natural silks were recognized early as a potential biomaterial for surgical threads or wound dressings; however, as biomedical engineering advances, the demand for high‐performance, naturally derived biomaterials becomes more pressing and stringent. A common problem of natural materials is their large batch‐to‐batch variation, the quantity available, their potentially high immunogenicity, and their fast biodegradation. Some of these common problems also apply to silk; therefore, recombinant approaches for producing silk proteins have been developed. There are several research groups which study and utilize various recombinantly produced silk proteins, and many of these have also investigated their products for biomedical applications. This review gives a critical overview over of the results for applications of recombinant silk proteins in biomedical engineering.
Breaking the Current‐Retention Dilemma in Cation‐Based Resistive Switching Devices Utilizing Graphene with Controlled Defects
Authors: Zhao Xiaolong , Ma Jun , Xiao Xiangheng , Liu Qi , Shao Lin , Chen Di , Liu Sen , Niu Jiebin , Zhang Xumeng , Wang Yan , Cao Rongrong , Wang Wei , Di Zengfeng , Lv Hangbing , Long Shibing , Liu Ming
Published: February 2018

Cation‐based resistive switching (RS) devices, dominated by conductive filaments (CF) formation/dissolution, are widely considered for the ultrahigh density nonvolatile memory application. However, the current‐retention dilemma that the CF stability deteriorates greatly with decreasing compliance current makes it hard to decrease operating current for memory application and increase driving current for selector application. By centralizing/decentralizing the CF distribution, this current‐retention dilemma of cation‐based RS devices is broken for the first time. Utilizing the graphene impermeability, the cation injecting path to the RS layer can be well modulated by structure‐defective graphene, leading to control of the CF quantity and size. By graphene defect engineering, a low operating current (≈1 µA) memory and a high driving current (≈1 mA) selector are successfully realized in the same material system. Based on systematically materials analysis, the diameter of CF, modulated by graphene defect size, is the major factor for CF stability. Breakthrough in addressing the current‐retention dilemma will instruct the future implementation of high‐density 3D integration of RS memory immune to crosstalk issues.
Nanomaterials Safer‐by‐Design: An Environmental Safety Perspective
Authors: Lin Sijie , Yu Tianyu , Yu Zhenyang , Hu Xialin , Yin Daqiang
Published: February 2018

Designing safer nanomaterials and nanostructures has gained increasing attention in the field of nanoscience and technology in recent years. Based on the body of experimental evidence contributed by environmental health and safety studies, materials scientists now have a better grasp on the relationships between the nanomaterials' physicochemical characteristics and their hazard/safety profiles. Therefore, it is expected that an integration of design synthesis and safety assessment will foster nanomaterials safer‐by‐design by considering both applications and implications. From the environmental safety perspective, the most recent advances that demonstrate effective nanomaterials safer‐by‐design are highlighted.
Preferential Charge Generation at Aggregate Sites in Narrow Band Gap Infrared Photoresponsive Polymer Semiconductors
Authors: Sulas Dana B. , London Alexander E. , Huang Lifeng , Xu Lihua , Wu Zhenghui , Ng Tse Nga , Wong Bryan M. , Schlenker Cody W. , Azoulay Jason D. , Sfeir Matthew Y.
Published: February 2018

Infrared organic photodetector materials are investigated using transient absorption spectroscopy, demonstrating that ultrafast charge generation assisted by polymer aggregation is essential to compensate for the energy gap law, which dictates that excited state lifetimes decrease as the band gap narrows. Short sub‐picosecond singlet exciton lifetimes are measured in a structurally related series of infrared‐absorbing copolymers that consist of alternating cyclopentadithiophene electron‐rich “push” units and strong electron‐deficient “pull” units, including benzothiadiazole, benzoselenadiazole, pyridalselenadiazole, or thiadiazoloquinoxaline. While the ultrafast lifetimes of excitons localized on individual polymer chains suggest that charge carrier generation will be inefficient, high detectivity for polymer:PC71BM infrared photodetectors is measured in the 0.6 < λ < 1.5 µm range. The photophysical processes leading to charge generation are investigated by performing a global analysis on transient absorption data of blended polymer:PC71BM films. In these blends, charge carriers form primarily at polymer aggregate sites on the ultrafast time scale (within our instrument response), leaving quickly decaying single‐chain excitons unquenched. The results have important implications for the further development of organic infrared optoelectronic devices, where targeting processes such as excited state delocalization over aggregates may be necessary to mitigate losses to ultrafast exciton decay as materials with even lower band gaps are developed.
Hydroaminomethylation in Aqueous Solvent Systems – An Efficient Pathway to Highly Functionalized Amines
Authors: Faßbach Thiemo A. , Sommer Fridolin O. , Vorholt Andreas J.
Published: February 2018

Tandem‐catalyzed hydroaminomethylation is a useful tool for synthesizing linear amines from olefins and amines in an atom‐efficient manner. To enable the coupling of highly functionalized, hydrosoluble amines with non‐water‐soluble olefins, this reaction must be transferred to aqueous biphasic solvent systems. In this work, we systematically evaluate reaction conditions to provide a selective hydroaminomethylation of 1‐octene with diethanolamine as model substrates. Although water is both the condensation side product and the solvent, yields of 79% were achieved using a catalytic system consisting a rhodium precursor and a sulfonated diphosphine ligand. This approach was applied to other functionalized amines, proving this concept is a suitable tool for the catalytic alkylation of highly functionalized amines.

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Characterization of the Valence and Conduction Band Levels of n = 1 2D Perovskites: A Combined Experimental and Theoretical Investigation
Authors: Silver Scott , Yin Jun , Li Hong , Brédas Jean‐Luc , Kahn Antoine
Published: February 2018

This study presents a combined experimental and theoretical study of the electronic structure of two 2D metal halide perovskite films. Ultraviolet and inverse photoemission spectroscopies are performed on solution‐processed thin films of the n = 1 layered perovskite butylammonium lead iodide and bromide, BA2PbI4 and BA2PbBr4, characterized by optical absorption and X‐ray diffraction, to determine their valence and conduction band densities of states, transport gaps, and exciton binding energies. The electron spectroscopy results are compared with the densities of states determined by density functional theory calculations. The remarkable agreement between experiment and calculation enables a detailed identification and analysis of the organic and inorganic contributions to the valence and conduction bands of these two hybrid perovskites. The electron affinity and ionization energies are found to be 3.1 and 5.8 eV for BA2PbI4, and 3.1 and 6.5 eV for BA2PbBr4. The exciton binding energies are estimated to be 260 and 300 meV for the two materials, respectively. The 2D lead iodide and bromide perovskites exhibit significantly less band dispersion and a larger density of states at the band edges than the 3D analogs. The effects of using various organic ligands are also discussed.
Mitigation of Inflammatory Immune Responses with Hydrophilic Nanoparticles
Authors: Li Bowen , Xie Jingyi , Yuan Zhefan , Jain Priyesh , Lin Xiaojie , Wu Kan , Jiang Shaoyi
Published: February 2018

While hydrophobic nanoparticles (NPs) have been long recognized to boost the immune activation, whether hydrophilic NPs modulate an immune system challenged by immune stimulators and how their hydrophilic properties may affect the immune response is still unclear. To answer this question, three polymers, poly(ethylene glycol) (PEG), poly(sulfobetaine) (PSB) and poly(carboxybetaine) (PCB), which are commonly considered hydrophilic, are studied in this work. For comparison, nanogels with uniform size and homogeneous surface functionalities were made from these polymers. Peripheral blood mononuclear cells (PBMCs) stimulated by lipopolysaccharide (LPS) and an LPS‐induced lung inflammation murine model were used to investigate the influence of nanogels on the immune system. Results show that the treatment of hydrophilic nanogels attenuated the immune responses elicited by LPS both in vitro and in vivo. Moreover, we found that PCB nanogels, which have the strongest hydration and the lowest non‐specific protein binding, manifested the best performance in alleviating the immune activation, followed by PSB and PEG nanogels. This reveals that the immunomodulatory effect of hydrophilic materials is closely related to their hydration characteristics and their ability to resist non‐specific binding in complex media.
Heteroleptic Copper(I)‐Based Complexes for Photocatalysis: Combinatorial Assembly, Discovery, and Optimization
Authors: Minozzi Clémentine , Caron Antoine , Grenier‐Petel Jean‐Christophe , Santandrea Jeffrey , Collins Shawn K.
Published: February 2018

A library of 50 copper‐based complexes derived from bisphosphines and diamines was prepared and evaluated in three mechanistically distinct photocatalytic reactions. In all cases, a copper‐based catalyst was identified to afford high yields, where new heteroleptic complexes derived from the bisphosphine BINAP displayed high efficiency across all reaction types. Importantly, the evaluation of the library of copper complexes revealed that even when photophysical data is available, it is not always possible to predict which catalyst structure will be efficient or inefficient in a given process, emphasizing the advantages for catalyst structures with high modularity and structural variability.
Thermally Rearranged Polymer Membranes Containing Tröger's Base Units Have Exceptional Performance for Air Separations
Authors: Meckler Stephen M. , Bachman Jonathan E. , Robertson Benjamin P. , Zhu Chenhui , Long Jeffrey R. , Helms Brett A.
Published: February 2018

The influence of segmental chain motion on the gas separation performance of thermally rearranged (TR) polymer membranes is established for TR polybenzoxazoles featuring Tröger's base (TB) monomer subunits as exceptionally rigid sites of contortion along the polymer backbone. These polymers are accessed from solution‐processable ortho‐acetate functionalized polyimides, which are readily synthesized as high‐molecular‐weight polymers for membrane casting. We find that thermal rearrangement leads to a small increase in d‐spacing between polymer chains and a dramatic pore‐network reconfiguration that increases both membrane permeability and O2/N2 selectivity, putting its performance above the 2015 upper bound.