bluuebunny/crossref_metadata_2025 huggingface dataset:
Sparse inverse fast Fourier transform‐based channel estimation for millimetre‐wave vector orthogonal frequency division multiplexing systems
Authors: Feng Qi , Zhou Haibo , Zhao Kanglian , Zhang Naitong
Published: April 2017

Millimetre‐wave propagation is a promising broadband transmission technology for future fifth generation mobile communication systems. For a vector orthogonal frequency division multiplexing system, the authors investigate the millimetre‐wave propagation through a sparse multipath channel in a sense that it has a large time delay spread but with only a few non‐zero taps. By exploiting the sparse nature of millimetre‐wave channel, any sparse multipath channel can be characterised by the multipath delays and their corresponding channel coefficients. They first study an ideal case that the pilot signals are transmitted through a sparse channel without noise, and an exactly sparse inverse fast Fourier transform (SIFFT) algorithm is performed to estimate the non‐zero channel taps with reduced complexity. Then, they consider a more practical scenario that the pilot signals through a sparse channel with noise interference, and an approximately SIFFT algorithm is employed to estimate the effective channel taps, while the remaining small coefficients interfered by noise can be wiped out. Through numerical analysis, they demonstrate that the proposed SIFFT algorithms can reduce the computational complexity while keeping the root mean squared error of channel estimation at a low level.
Arthroscopic Scaphoid 3D Test for Scapholunate Instability
Authors: Ocampos Montserrat , Cerro Miguel , Corella Fernando
Published: April 2017

Background Patients with scapholunate instability usually have pain in the dorsal wrist. This pain may occur due to the impingement between the scaphoid and the dorsal rim of the radius when the scaphoid is detached from the lunate. This pain appears as the scaphoid is displaced over the dorsal rim of the radius. The arthroscopic scaphoid 3D (dorsal, dynamic, displacement) test is described here to check this pathologic dorsal displacement of the scaphoid.

Surgical Technique The test should be performed both in the radiocarpal and midcarpal joints. Traction is released and the arthroscope is set under the lunate when tested in the radiocarpal joint and on the lunate when tested in the midcarpal joint. The scaphoid is manually pushed dorsally at the scaphoid tubercle. If there was no scapholunate instability, all the proximal row bones are minimally displaced: a negative test. If there was scapholunate instability, the scaphoid is displaced dorsally while the lunate remains static: evaluated as positive.

Clinical Relevance This test can add information to the arthroscopic classifications of the scapholunate instability, which explore both the proximal to distal displacement of the scaphoid (the step-off) and the ulnar to radial displacement (the gap), as this test explores the volar to dorsal displacement.
Impact of Remote Ischemic Postconditioning during Primary Percutaneous Coronary Intervention on Left Ventricular Remodeling after Anterior Wall ST-Segment Elevation Myocardial Infarction: A Single-Center Experience
Authors: Awad Omar , Raymond Ramy , Badran Haytham , Mostafa Ahmad , Saad Marwan , Elbadawi Ayman
Published: April 2017

The role of remote ischemic postconditioning (RIPostC) in improving left ventricular (LV) remodeling after primary percutaneous coronary intervention (PCI) is not well established. To determine the efficacy and safety of RIPostC in improving LV remodeling and cardiovascular outcomes after primary PCI for anterior ST-elevation myocardial infarction (STEMI). Seventy-one patients with anterior STEMI were randomized to primary PCI with RIPostC protocol (n = 36) versus conventional primary PCI (n = 35). Primary outcomes included LV remodeling and LV ejection fraction (LVEF) at 6 month follow-up using transthoracic echocardiography. Secondary outcomes included infarct size, ST-segment resolution (STR) ≥70%, Thrombolysis in Myocardial Infarction (TIMI) flow grade, and myocardial blush grade (MBG). Major adverse cardiac events (MACEs) were also assessed at 6 months. Safety outcome included incidence of acute kidney injury (AKI) postprimary PCI. Sixty patients completed the study. At 6 months, there was no significant decrease in the incidence of LV remodeling with RIPostC group (p = 0.42). Similarly, RIPostC failed to show significant improvement in LVEF. However, STR ≥ 70% after primary PCI was achieved more in the RIPostC group (p = 0.04), with a trend toward less AKI in the RIPostC group (p = 0.08). All other secondary end points, including MACEs at 6 months, were similar in both groups. RIPostC might be associated with better STR after reperfusion as well as less incidence of AKI in patients undergoing primary PCI for anterior wall STEMI, indicating potential benefit in those patients. Whether this role can be translated to better outcomes after primary PCI warrants further investigation.
Religiöse/spirituelle Bedürfnisse und psychosoziale Belastung von Patienten mit malignem Melanom
Authors: Haußmann Annette , Schäffeler Norbert , Hautzinger Martin , Weyel Birgit , Eigentler Thomas , Zipfel Stephan , Teufel Martin
Published: April 2017

Während einer Krebserkrankung stellen sich Fragen nach Lebenssinn in neuer Prägnanz. Studien zeigen, dass ein Großteil der Patienten spirituelle Bedürfnisse äußern und Religiosität/ Spiritualität eine wichtige Ressource in der Krankheitsbewältigung sein kann. Bislang liegen zur Entwicklung psychischer Belastung und der Rolle spiritueller Bedürfnisse im Krankheits- und Behandlungsverlauf von Patienten mit malignem Melanom wenige Studien vor.

Die Studie untersucht religiöse/spirituelle Bedürfnisse und psychosoziale Belastungen bei n=22 Patienten mit malignem Melanom zu 2 Zeitpunkten: stationärer Aufenthalt zur Entfernung der Wächterlymphknoten (t1) sowie 8 Wochen später (t2). Distress, Angst, Depressivität sowie spirituelle Bedürfnisse und Religiosität wurden mithilfe standardisierter Assessments (HSI, DT, HADS, PHQ; SpNQ; SpREUK) erfasst.

Unabhängig von Belastung und Messzeitpunkt äußerten alle Patienten spirituelle Bedürfnisse. Besonders wichtig waren das Bedürfnis nach ganzheitlichem Heilsein, sozialer Einbindung, Gewissheit von Lebenssinn und Gespräch über Sorgen und Ängste. Es zeigte sich eine geringere psychische Belastung von Patienten, die sich selbst als religiös bezeichneten.

Die Ergebnisse zeigen die Relevanz einer Berücksichtigung von spirituellen Bedürfnissen im klinischen und ambulanten Kontext der Krebsbehandlung. Die Befunde deuten außerdem darauf hin, dass Religiosität/Spiritualität eine wichtige Ressource bei der Krankheitsverarbeitung sein kann.

Spirituelle Bedürfnisse sollten im Behandlungsprozess im Sinne eines integrativen Behandlungskonzepts sowohl von psychoonkologischer als auch von seelsorgerlicher Seite erfragt und berücksichtigt werden.
Surface velocity divergence model of air/water interfacial gas transfer in open-channel flows
Authors: Sanjou M. , Nezu I. , Okamoto T.
Published: April 2017

Air/water interfacial gas transfer through a free surface plays a significant role in preserving and restoring water quality in creeks and rivers. However, direct measurements of the gas transfer velocity and reaeration coefficient are still difficult, and therefore a reliable prediction model needs to be developed. Varying systematically the bulk-mean velocity and water depth, laboratory flume experiments were conducted and we measured surface velocities and dissolved oxygen (DO) concentrations in open-channel flows to reveal the relationship between DO transfer velocity and surface divergence (SD). Horizontal particle image velocimetry measurements provide the time-variations of surface velocity divergence. Positive and negative regions of surface velocity divergence are transferred downstream in time, as occurs in boil phenomenon on natural river free-surfaces. The result implies that interfacial gas transfer is related to bottom-situated turbulence motion and vertical mass transfer. The original SD model focuses mainly on small-scale viscous motion, and this model strongly depends on the water depth. Therefore, we modify the SD model theoretically to accommodate the effects of the water depth on gas transfer, introducing a non-dimensional parameter that includes contributions of depth-scale large-vortex motion, such as secondary currents, to surface renewal events related to DO transport. The modified SD model proved effective and reasonable without any dependence on the bulk mean velocity and water depth, and has a larger coefficient of determination than the original SD model. Furthermore, modeling of friction velocity with the Reynolds number improves the practicality of a new formula that is expected to be used in studies of natural rivers.
Progress on bioinspired, biomimetic, and bioreplication routes to harvest solar energy
Authors: Martín-Palma Raúl J. , Lakhtakia Akhlesh
Published: April 2017

Although humans have long been imitating biological structures to serve their particular purposes, only a few decades ago engineered biomimicry began to be considered a technoscientific discipline with a great problem-solving potential. The three methodologies of engineered biomimicry––viz., bioinspiration, biomimetic, and bioreplication––employ and impact numerous technoscientific fields. For producing fuels and electricity by artificial photosynthesis, both processes and porous surfaces inspired by plants and certain marine animals are under active investigation. Biomimetically textured surfaces on the subwavelength scale have been shown to reduce the reflectance of photovoltaic solar cells over the visible and the near-infrared regimes. Lenticular compound lenses bioreplicated from insect eyes by an industrially scalable technique offer a similar promise.
Fermionic modular categories and the 16-fold way
Authors: Bruillard Paul , Galindo César , Hagge Tobias , Ng Siu-Hung , Plavnik Julia Yael , Rowell Eric C. , Wang Zhenghan
Published: April 2017

We study spin and super-modular categories systematically as inspired by fermionic topological phases of matter, which are always fermion parity enriched and modelled by spin topological quantum field theories at low energy. We formulate a 16-fold way conjecture for the minimal modular extensions of super-modular categories to spin modular categories, which is a categorical formulation of gauging the fermion parity. We investigate general properties of super-modular categories such as fermions in twisted Drinfeld doubles, Verlinde formulas for naive quotients, and explicit extensions of PSU(2)4m+2 with an eye towards a classification of the low-rank cases.
Ripple formation on silver after irradiation with radially polarised ultrashort-pulsed lasers
Authors: Tsibidis George D. , Stratakis Emmanuel
Published: April 2017

We report on the morphological effects induced by the inhomogeneous absorption of cylindrically polarized femtosecond laser irradiation of silver (Ag) in sub-ablation conditions. A theoretical prediction of the role of surface plasmon excitation and thermal effects in the production of self-formed periodic ripples structures is evaluated. To this end, a combined hydrodynamical and thermoelastic model is presented to account for the influence of temperature-related lattice movements in laser beam conditions that are sufficient to produce material melting. The results indicate that material displacements due to hydrodynamics are substantially larger than strain-related movements, which also emphasises the predominant role of fluid transport in surface modification. Moreover, theoretical simulations highlight the influence of the polarisation state in the size of ripple periodicity for a specialized case of cylindrically polarized beams, the radially polarized beams. The results show that the ripple periodicity is larger if linearly polarized beams are used. This is the opposite trend to the behaviour for materials with decreasing electron-phonon coupling constant g with increasing electron temperature, which highlights the significant role of g.
Apparent bandgap shift in the internal quantum efficiency for solar cells with back reflectors
Authors: Steiner M. A. , Perl E. E. , Geisz J. F. , Friedman D. J. , Jain N. , Levi D. , Horner G.
Published: April 2017

We demonstrate that in solar cells with highly reflective back mirrors, the measured internal quantum efficiency exhibits a shift in bandgap relative to the measured external quantum efficiency. The shift arises from the fact that the measured reflectance at the front surface includes a superposition of waves reflecting from the front and back surfaces. We quantify the magnitude of the apparent shift and discuss the errors that can result in determination of quantities such as the photocurrent. Because of this apparent shift, it is important the bandgap be determined from the external quantum efficiency.
Decisive test of the ideal behavior of tetra-PEG gels
Authors: Horkay Ferenc , Nishi Kengo , Shibayama Mitsuhiro
Published: April 2017

The objective of this work is to investigate the thermodynamic and scattering behavior of tetra-poly(ethylene glycol) (PEG) gels. Complementary measurements, including osmotic swelling pressure, elastic modulus, and small angle neutron scattering (SANS), are reported for a series of tetra-PEG gels made from different molecular weight precursor chains at different concentrations. Analysis of the osmotic swelling pressure vs polymer volume fraction curves makes it possible to separate the elastic and mixing contributions of the network free energy. It is shown that in tetra-PEG gels these free energy components are additive. The elastic term varies with the one-third power of the polymer volume fraction and its numerical value is equal to the shear modulus obtained from independent mechanical measurements. The mixing pressure of the cross-linked polymer is slightly smaller than that of the corresponding solution of the uncross-linked polymer of infinite molecular weight but it exhibits similar dependence on the polymer concentration. The observed deviation between the osmotic mixing pressures of the gel and the solution can be attributed to the presence of small amount of structural inhomogeneities frozen-in by the cross-links. SANS reveals that the scattering response of tetra-PEG gel is mainly governed by the thermodynamic concentration fluctuations of the network, i.e., the contribution from static inhomogeneities to the SANS signal is small.
Pressure-induced boron nitride nanotube derivatives: 3D metastable allotropes
Authors: Xiong Mei , Luo Kun , Yu Dongli , Zhao Zhisheng , He Julong , Gao Guoying
Published: April 2017

The high-pressure behaviors of large-diameter single-walled boron nitride nanotubes (BNNTs) are studied by the first-principles method. One sp3-hybridized and three sp2/sp3-hybridized BN allotropes are obtained via compressing large diameter BNNTs. Due to the restricted movement of nonequivalent B and N atoms, the large BN nanotubes have a chance to form B-B and N-N bonds between intertubes under pressure, in addition to the common B-N bonds. The electron localization function and Mulliken's population analysis indicate the covalent nature of the B-B and N-N dimers. The electronic band structure and density of state calculations show a local conducting feature of tP24-BN and superhard semiconducting character of the other three allotropes with indirect band gaps of 1.28 – 3.13 eV.
Equilibrium and stability of a gravitationally bound uniformly charged dust cloud
Authors: Avinash K. , Gaurav Sweta
Published: April 2017

An exactly solvable model of equilibrium and stability of a gravitationally bound low dust density cloud embedded in background plasma is described. The dust is distributed almost homogeneously within the cloud. The corresponding eigen value equation is solved using the Frobenius method to calculate the complete set of radial eigen modes and corresponding frequencies. The low dust density cloud is shown to be stable. This model can be useful in benchmarking simulation codes and modelling dust density distribution in the interstellar cloud in the HII region.
Core–shell Y-substituted Nd–Ce–Fe–B sintered magnets with enhanced coercivity and good thermal stability
Authors: Fan Xiaodong , Chen Kan , Guo Shuai , Chen Renjie , Lee Don , Yan Aru , You Caiyin
Published: April 2017

Although Nd–Ce–Fe–B permanent magnets are inexpensive, they have degraded coercivity and poor thermal stability. To mitigate these disadvantages, in this work, we fabricated a core–shell grain structure with a Y-rich core and a (Nd, Ce)-rich shell in the Nd15.25(Ce1−xYx)15.25FebalAl0.1Cu0.1B (x = 0, 0.05, 0.10, 0.15, and 0.20) system by substituting Y for Ce. Substituting Y increased the coercivity from 7.13 kOe in the Ce1.00Y0.00 (x = 0) magnet to 9.73 kOe in the Ce0.85Y0.15 (x = 0.15) magnet. The thermal stability of its magnetic performance also improved with Y substitution, with lower temperature coefficients of remanence |α| and coercivity |β|. We explained these improvements in magnetic properties by examining the relationship between the microstructure and the properties of the core–shell grain structure.
Time-dependent perpendicular transport of energetic particles in magnetic turbulence with transverse complexity
Authors: Shalchi A.
Published: April 2017

The motion of energetic particles in magnetic turbulence across a mean magnetic field is explored analytically. The approach presented here allows for a full time-dependent description of the transport, including compound sub-diffusion. For the first time it is shown systematically that as soon as there is a transverse structure of the turbulence, diffusion is restored even if no Coulomb collisions are invoked. Criteria for sub-diffusion and normal Markovian diffusion are found as well.
An improved CROPR model for estimating cotton yield under soil aeration stress
Authors: Qian Long , Wang Xiu-Gui , Luo Wen-Bing , Qi Zhi-Ming , Sun Huai-Wei , Luo Yun-Ying
Published: April 2017

Accurate estimation of crop yield under aeration stress is crucial for field water table management. In this study, the CROPR crop model was improved in two aspects: (i) a new aeration factor, which was related to a drainage index, was proposed and used to represent the condition of soil aeration; and (ii) a multiplicative structure, instead of the original additive structure, was used in the calculation of dry matter accumulation to include the after-effect of aeration stress. Four-year lysimeter experiments on cotton (Gossypium hirsutum L.) growth under aeration stress were conducted from 2008 to 2011 to calibrate and validate both the original and improved CROPR. The results indicated that the improved CROPR performed better than the original CROPR and was suitable for simulating cotton yield under aeration stress. In the calibration, with the improved CROPR, the root-mean-squared error (RMSE) of seed cotton yield was 832.84 kg ha–1 with a normalised value (NRMSE) of 15.87%, whereas with the original CROPR, the RMSE was 973.03 kg ha–1 with an NRMSE of 18.55%. In the validation, with the improved CROPR, the RMSE of seed cotton yield was 686.22 kg ha–1 with an NRMSE of 14.87%; with the original CROPR, the RMSE was 1019.02 kg ha–1 with an NRMSE of 22.08%.
Stayin' on Track: the feasibility of developing Internet and mobile phone-based resources to support young Aboriginal fathers
Authors: Fletcher Richard , Hammond Craig , Faulkner Darren , Turner Nicole , Shipley Lisa , Read Donna , Gwynn Josephine
Published: April 2017

Young Aboriginal fathers face social and emotional challenges in the transition to fatherhood, yet culturally appropriate support mechanisms are lacking. Peer mentoring to develop online- and mobile phone-based resources and support may be a viable approach to successfully engage these young men. This feasibility study engaged two trusted Aboriginal mentors and researchers to partner with one regional and two rural Aboriginal communities in New South Wales, Australia. Early in the research process, 20 young Aboriginal fathers were recruited as co-investigators. These fathers were integral in the development of web-based resources and testing of mobile phone-based text messaging and mood-tracking programs tailored to provide fathering and mental health support. Overwhelmingly positive feedback from evaluations reinforced community pride in and ownership of the outcomes. The young men’s involvement was instrumental in not only developing culturally appropriate support, but also in building their capacity as role models for other fathers in the community. The positive results from this feasibility study support the adoption of participatory approaches in the development of resources for Aboriginal communities.
Jung’s Red Book, improvisation, and the mētic spirit
Authors: Fertel Randy
Published: April 2017

UnderstandingThe Red Book as an improvisation and Jung as an improviser offers a new approach to understanding the active imagination and the analytic method that emerged from it. Such an approach uncovers the mētic spirit – the spirit of polytropic intelligence – that informsThe Red Bookand the archetypal figure of Hermes/Mercurius/Trickster that informs all improvisations and will come to dominate Jung’s career. The rhetoric of improvisation inThe Red Bookconveys that, uncontaminated by the directed consciousness or ego, personae and imagoes arise spontaneously from his unconscious and control him, not he them. Such gestures privilege non-rational ways of making art and knowing the self and world, part and parcel of the paradigm shift that characterizes the 20th century. Jung’s Red Book is on the leading edge of that effort to shift from objective rationality to a rationality that can embrace subjective elements: the unconscious and the irrational, not just the “broad highways” but also the “back alleys” of human experience.
The negative-differential-resistance (NDR) mechanism of a hydroelastic microfluidic oscillator
Authors: Xia H M , Wu J W , Wang Z P
Published: April 2017

A microfluidic oscillator is of interest because it converts a stable laminar flow to oscillatory flow, especially in view of the fact that turbulence is typically absent in miniaturized fluidic devices. One important design approach is to utilize hydroelastic effect-induced autonomous oscillations to modify the flow, so to reduce the reliance on external controllers. However, as complex fluid-structure interactions are involved, the prediction of its mechanism is rather challenging. Here, we present a simple equivalent circuit model and investigate the negative-differential-resistance (NDR) mechanism of a hydroelastic microfluidic oscillator. We show that a variety of complex flow behaviors including the onset of oscillation, formation of different oscillation patterns, collapse of the channel, etc can be well explained by this model. It provides a generic approach for construction of microfluidic NDR oscillators, following which a new design is also proposed. Relevant findings give more insights into the hydroelastic instability problems in microfluidics, and enrich the study of microfluidic flow control devices based on the electric circuit theory.
Microtubule dynamics drive enhanced chromatin motion and mobilize telomeres in response to DNA damage
Authors: Lawrimore Josh , Barry Timothy M. , Barry Raymond M. , York Alyssa C. , Friedman Brandon , Cook Diana M. , Akialis Kristen , Tyler Jolien , Vasquez Paula , Yeh Elaine , Bloom Kerry
Published: April 2017

Chromatin exhibits increased mobility on DNA damage, but the biophysical basis for this behavior remains unknown. To explore the mechanisms that drive DNA damage–induced chromosome mobility, we use single-particle tracking of tagged chromosomal loci during interphase in live yeast cells together with polymer models of chromatin chains. Telomeres become mobilized from sites on the nuclear envelope and the pericentromere expands after exposure to DNA-damaging agents. The magnitude of chromatin mobility induced by a single double-strand break requires active microtubule function. These findings reveal how relaxation of external tethers to the nuclear envelope and internal chromatin–chromatin tethers, together with microtubule dynamics, can mobilize the genome in response to DNA damage.
Nanonet force microscopy for measuring forces in single smooth muscle cells of the human aorta
Authors: Hall Alexander , Chan Patrick , Sheets Kevin , Apperson Matthew , Delaughter Christopher , Gleason Thomas G. , Phillippi Julie A. , Nain Amrinder
Published: April 2017

A number of innovative methods exist to measure cell–matrix adhesive forces, but they have yet to accurately describe and quantify the intricate interplay of a cell and its fibrous extracellular matrix (ECM). In cardiovascular pathologies, such as aortic aneurysm, new knowledge on the involvement of cell–matrix forces could lead to elucidation of disease mechanisms. To better understand this dynamics, we measured primary human aortic single smooth muscle cell (SMC) forces using nanonet force microscopy in both inside-out (I-O intrinsic contractility) and outside-in (O-I external perturbation) modes. For SMC populations, we measured the I-O and O-I forces to be 12.9 ± 1.0 and 57.9 ± 2.5 nN, respectively. Exposure of cells to oxidative stress conditions caused a force decrease of 57 and 48% in I-O and O-I modes, respectively, and an increase in migration rate by 2.5-fold. Finally, in O-I mode, we cyclically perturbed cells at constant strain of varying duration to simulate in vivo conditions of the cardiac cycle and found that I-O forces decrease with increasing duration and O-I forces decreased by half at shorter cycle times. Thus our findings highlight the need to study forces exerted and felt by cells simultaneously to comprehensively understand force modulation in cardiovascular disease.
Washes and Hues: Reading for Colour in Marie NDiaye
Authors: Jordan Shirley
Published: April 2017

This article analyses Marie NDiaye’s experimentation with colour and colour values, and argues that she sets out to unsettle the way we think about colour. For the main part colour — and indeed colour blindness — in the author’s work have been explored through scrutiny of her progressively more detailed attentiveness to experiences and perceptions of skin colour in contemporary France. Yet colour is deployed and investigated in numerous distinctive and often painterly ways in her writing; ways which suggest her interest in other than racialized paradigms and which attune us to colour processing and human cognition, to emotional responses to colour, and to an ethical issue that is perpetually at stake in our engagement with her work: empathy. Through analysis of her colour-writing in selected texts, especially
La Naufragée
(1999),
Rosie Carpe
(2001), and
Autoportrait en vert
(2006), this article explores NDiaye’s chromatic experimentation as a linchpin for asking probing questions about emotion, memory, the senses, perception, self-perception, creativity, and mental disorder in modern and contemporary writing in French. Specific dimensions of the author’s colour practice, namely her interest in all-suffusing washes and her declining of hues of a given colour (here, yellow and green) are given detailed attention, and important painterly and literary intertexts are examined.
GSuite HyperBrowser: integrative analysis of dataset collections across the genome and epigenome
Authors: Simovski Boris , Vodák Daniel , Gundersen Sveinung , Domanska Diana , Azab Abdulrahman , Holden Lars , Holden Marit , Grytten Ivar , Rand Knut , Drabløs Finn , Johansen Morten , Mora Antonio , Lund-Andersen Christin , Fromm Bastian , Eskeland Ragnhild , Gabrielsen Odd Stokke , Ferkingstad Egil , Nakken Sigve , Bengtsen Mads , Nederbragt Alexander Johan , Thorarensen Hildur Sif , Akse Johannes Andreas , Glad Ingrid , Hovig Eivind , Sandve Geir Kjetil
Published: April 2017

Background:

Recent large-scale undertakings such as ENCODE and Roadmap Epigenomics have generated experimental data mapped to the human reference genome (as genomic tracks) representing a variety of functional elements across a large number of cell types. Despite the high potential value of these publicly available data for a broad variety of investigations, little attention has been given to the analytical methodology necessary for their widespread utilisation.

Findings:

We here present a first principled treatment of the analysis of collections of genomic tracks. We have developed novel computational and statistical methodology to permit comparative and confirmatory analyses across multiple and disparate data sources. We delineate a set of generic questions that are useful across a broad range of investigations and discuss the implications of choosing different statistical measures and null models. Examples include contrasting analyses across different tissues or diseases. The methodology has been implemented in a comprehensive open-source software system, the GSuite HyperBrowser. To make the functionality accessible to biologists, and to facilitate reproducible analysis, we have also developed a web-based interface providing an expertly guided and customizable way of utilizing the methodology. With this system, many novel biological questions can flexibly be posed and rapidly answered.

Conclusions:

Through a combination of streamlined data acquisition, interoperable representation of dataset collections, and customizable statistical analysis with guided setup and interpretation, the GSuite HyperBrowser represents a first comprehensive solution for integrative analysis of track collections across the genome and epigenome. The software is available at: https://hyperbrowser.uio.no.
Changes in spatial and temporal variability of prey affect functional connectivity of larval and juvenile cod
Authors: Lough R. Gregory , Broughton Elisabeth A. , Kristiansen Trond
Published: April 2017

Changes in structural connectivity as it can affect functional connectivity, the biological and behavioural responses of an organism, has been examined here over 2 contrasting years when the spatial distribution of larval and juvenile cod and their prey shifted from the flank to the crest on Georges Bank. New data on the gut contents of pelagic juvenile cod are compared with known prey distributions, potential growth and how climate warming can change connectivity in this region. Centropages spp. was the most important prey for pelagic juveniles, especially in June 1987 when they had high abundance on the crest and were dominant in the cod stomachs. In June 1986, copepod abundance was low where the juveniles were distributed along the flank. The potential growth of juvenile cod was greater in June 1987, consistent with the higher abundance of Centropages spp., and with higher recruitment survival, compared with June 1986. Annual changes in the spatial distribution of cod early life stages within the environment of cold or warm years can have different impacts on their growth and survival. Whereas the small copepods, Pseudocalanus spp., are primary prey for cod larvae and very abundant in cold years, larger copepods, Calanus finmarchicus and Centropages spp., are important prey for the pelagic juveniles and the latter species can have a high impact in warm years on the crest. The different spatial structure during cold or warm years provides an explanation why different year classes respond differently to environmental change. Depending on the presence or absence of specific prey, the functional connectivity response changes pathways that determine the growth and survival of early life stages and ultimately a role in recruitment.
Assessment of biological maturation
Authors: Malina Robert M
Published: April 2017

The processes of growth and maturation occur concurrently and are related. Chapter 1 discusses indicators of growth status and rate followed by a description of methods for assessment of maturity status and timing. Status refers to the state of maturation at the time of observation. Skeletal age and stages of puberty indicate status. Timing refers to the chronological age at which specific maturational events occur. Ages at peak height velocity (PHV) and at menarche are used most often. Skeletal age is applicable from childhood through adolescence; other indicators of status and timing are limited to the interval of puberty and the growth spurt. Increasingly used non-invasive indicators of maturation include percentage of predicted adult height attained at the time of observation (status) and predicted maturity offset or time before age at PHV (timing). Both have limitations and require further validation.
Developmental biodynamics
Authors: Watkins James
Published: April 2017

From a dynamical systems perspective, coordination of human movement emerges from the intrinsic self-organizing properties of the dynamical system consisting of the individual, the task, and the environment. The movement pattern that emerges depends upon the state of the system components which impose constraints on the types of movement that may emerge. These constraints arise from the anthropometry and functional ability of the individual (individual constraints), the requirements of the task (task constraints), and the prevailing environmental conditions (environmental constraints). Abnormal movement due to cerebral palsy, disease, or injury is likely to be due to abnormal individual constraints in the form of abnormal energy resources. Therapy directed at normalizing the abnormal energy resources is likely to be more effective than therapy directed at normalizing the abnormal kinematics.
Exercise and hormones
Authors: Eliakim Alon , Nemet Dan
Published: April 2017

The complex endocrine response to exercise in children and adolescents includes significant changes in hormones that regulate muscle adaptations and growth. Better understanding of this system makes the possible use of hormonal changes as an objective tool to gauge exercise intensity and duration, to assess training response, and to improve our understanding of the beneficial and deleterious hormonal effects of competitive sports (e.g. on growth and reproduction). Moreover, better understanding of the unique relationship between exercise and the endocrine system is important not only for children and adolescents engaged in competitive sports, but also to those with chronic diseases and disabilities who wish or need to increase their physical activity levels. The effect of a single exercise bout on the endocrine system and in particularly on the GH-IGF-I axis, the reproductive system, and the adrenal gland is discussed.
Maximal-intensity exercise
Authors: Williams Craig A , Ratel Sébastien
Published: April 2017

Maximal intensity is any activity where the exercise-supplying metabolism demonstrates a higher anaerobic ATP yield than the oxidative phosphorylation metabolism. Ethical considerations prevent muscle biopsy techniques in young people, resulting in indirect inferences about anaerobic metabolism during exercise being applied to mostly mechanically derived measurements. These measurements are largely based on cycle ergometry tests like the Wingate test. Compared to aerobic data, maximal-intensity data sets are infrequently published, female data across all age ranges are lacking, and application is limited by a focus on sports performance rather than health. However, regardless of how these data are analysed, children and adolescent performance is inferior to adults. Most studies attempt to explain this from a quantitative muscle (and age) perspective, while explanations of qualitative factors, e.g. hormonal and neuromuscular, have proved elusive. Future studies should focus on the mechanisms underpinning maximal-intensity exercise as an important component of everyday physical activity.
Neuromuscular fatigue
Authors: Ratel Sébastien , Williams Craig A
Published: April 2017

Scientific evidence supports the proposition that prepubertal children fatigue less than adults when performing whole-body dynamic activities like maximal cycling, running bouts, and maximal voluntary isometric/isokinetic muscle contractions. Although the mechanisms underpinning differences in fatigue between children and adults are not all fully understood, there is a consensus that children experience less peripheral fatigue (i.e. muscular fatigue) than their older counterparts. Central factors may also account for the lower fatigability in children. Some studies report a higher reduction of muscle voluntary activation during fatiguing exercise in prepubertal children compared to adults. This could reflect a strategy of the central nervous system aimed at limiting the recruitment of motor units, in order to prevent any extensive peripheral fatigue. Further studies are required to clarify this proposition.
Aerobic fitness
Authors: Armstrong Neil , McManus Alison M
Published: April 2017

Peak oxygen uptake (V̇O2) is the criterion measure of young people's aerobic fitness, and blood lactate accumulation (BLA) is a useful indicator of aerobic fitness with reference to the ability to sustain submaximal exercise. In sport and in everyday life it is the pulmonary (p)V̇O2 kinetics of the non-steady state which best assess the integrated responses of the oxygen delivery system and the metabolic demands of the exercising muscle. Data analysis using sophisticated modelling techniques has enhanced understanding of sexual dimorphism and the independent effects of chronological age, body size, and biological maturity on peak V̇O2 and BLA. The extant data on young people's pV̇O2 kinetic responses to step changes in exercise intensity are sparse, but describe intriguing chronological age and sex differences across exercise domains. However, independent effects of biological maturation are yet to be revealed.
Temperature regulation
Authors: Falk Bareket , Dotan Raffy
Published: April 2017

Under all but the most extreme environmental heat conditions, children control their body temperature (at rest and during exercise) as well as adults. Children, however, use a different thermoregulatory strategy. Compared with adults, children rely more on dry heat dissipation and less on evaporative cooling (sweating). Their larger skin surface-area relative to mass does put children at increasing disadvantage, relative to adults, as ambient temperatures rise above skin temperature. Similarly, they become increasingly disadvantaged upon exposure to decreasing temperatures below the thermo-neutral zone. Like adults, children inadvertently dehydrate while exercising in hot conditions and are often hypohydrated, even before exercise, and their core temperature rises considerably more than adults in response to a given fluid (sweat) loss, which may put them at higher risk for heat-related injury. However, epidemiological data show rates of both heat- and cold-related injuries among children and adolescents as similar or lower than at any other age.
Genetics of physical activity and physical fitness
Authors: Schutte Nienke M , Bartels Meike , de Geus Eco JC
Published: April 2017

Regular physical activity and fitness are key contributors to children’s health. It is important to understand sources of variation in phenotypes seen among children and adolescents. It is important to calculate the relative importance of genetic and environmental factors to observed individual differences. Heritability estimates of physical activity vary, depending on sample size and measurement instrument, but the overall importance of environmental factors seems to decrease in adolescence, whereas genetic effects become more prominent. Twin and family studies show that individual differences in maximal oxygen uptake, muscle strength, flexibility, and balance are affected by genetic factors. Some evidence is found for specific genes coding for physical activity and fitness, but children and adolescent studies are limited. Future research should prioritize these target groups as knowledge of the source of individual differences in physical activity and fitness at different time points can optimize the choice and timing of exercise intervention.
Systematic promotion of physical activity
Authors: Kremers Stef , Meertens Ree M , Ruiter Robert AC
Published: April 2017

Relevant theoretical and empirical insights regarding the development of interventions to promote physical activity in young people are overviewed. It is argued that physical activity-promoting programmes should be based on a systematic approach combining empirical findings, theoretical insights, and practical considerations. Successful health promotion interventions to increase physical activity typically consist of strategies to improve intra-personal determinants of physical activity, as well as environmental strategies that facilitate the behaviour, break unhealthy habits, or sustain healthy ones. The Intervention Mapping protocol can be a helpful tool in the systematic development, implementation, diffusion, and evaluation of interventions aimed at the promotion of physical activity in young people.
Exercise, physical activity, and diabetes mellitus
Authors: van Mil Edgar GAH
Published: April 2017

The main aim for the diabetic child is to live as normal a life as possible via four main targets of management: obtaining good metabolic control, preventing long-term complications, promoting social competence, and self-worth. The main challenges are that the child must receive appropriate insulin subcutaneously and there must be attention given to lifestyle. Participation in sports not only helps to reach those targets, but also forms a great challenge in maintaining good metabolic control as physical activity has an impact on glucose utilization. This chapter discusses the definition of diabetes mellitus, the diagnostic criteria, the aetiology, and the clinical spectrum, as well as all the practical aspects encountered by the child with diabetes mellitus and his/her care givers and how it all relates to sports and physical activity. Finally, it covers strategies to optimize performance and prevent complications.
Exercise, physical activity, and asthma
Authors: Hebestreit Helge , Kriemler Susi , Radtke Thomas
Published: April 2017

The incidence of asthma in children varies among countries and can be estimated to range between 5% and 20%. Exercise-induced asthma (EIA) is common in patients with asthma but can also occur in some children without asthma. Typical symptoms of EIA include cough, chest tightness, and shortness of breath shortly after exercise. The pathophysiology of EIA is not completely understood, but it has been shown that airway cooling and drying with increased ventilation during exercise and airway re-warming after exercise play a pivotal role. In addition, a lack of physical activity may also contribute to EIA. Regular exercise may increase fitness and psychological well-being but may also positively influence airway inflammation in children with asthma. The diagnosis of EIA is based on the typical history and may be verified by an exercise challenge test. Every child with EIA should be able to engage in all type of physical activities.
Exercise, physical activity, and cystic fibrosis
Authors: Kriemler Susi , Radtke Thomas , Hebestreit Helge
Published: April 2017

Cystic fibrosis (CF) is a genetic disease resulting in an impaired mucociliary clearance, chronic bacterial airway infection, and inflammation. The progressive destruction of the lungs is the main cause of morbidity and premature death. Diverse other organ systems such as heart, muscles, bones, gastro-intestinal tract, and sweat glands are often also affected and interfere with exercise capacity. Hence, exercise capacity is reduced as the disease progresses mainly due to reduced functioning of the muscles, heart, and/or lungs. Although there is still growing evidence of positive effects of exercise training in CF on exercise capacity, decline of pulmonary function, and health-related quality of life, the observed effects are encouraging and exercise should be implemented in all patient care. More research is needed to understand pathophysiological mechanisms of exercise limitations and to find optimal exercise modalities to slow down disease progression, predict long-term adherence, and improve health-related quality of life.
Exercise, physical activity, and children with physical or intellectual disabilities
Authors: Zetaruk Merrilee , Mustapha Shareef F
Published: April 2017

Many physical and psychological benefits of exercise and sport participation exist for blind or deaf children, as well as children with disabilities such as cerebral palsy, myelomeningocoele, spinal cord injury, and amputations. There are also a number of challenges these children must face in these endeavours. It is important to understand the injuries to which children with disabilities are predisposed and general strategies for prevention. Some adaptations via adjustments in rules and use of specialized wheelchairs and prosthetic devices allow participation in a more diverse range of athletic activity for this population. Many opportunities exist for children with disabilities, including Down syndrome and other intellectual disabilities, to participate in sports at a local or recreational level, all the way to the elite level in the Paralympic Games and Special Olympic World Games. It is important that health professionals become familiar with the unique challenges faced by these individuals.
Molecular exercise physiology
Authors: Wackerhage Henning , Smith Jonathon , Wisniewski Darren
Published: April 2017

Molecular exercise physiology is the study of exercise physiology using molecular biology methods. The development of differentiated cell types is regulated by transcription factors like the muscle-making MyoD that specifies cell type, while others regulate the development of muscle, tendons, and bones. Maternal nutrition and exercise commonly affect embryonic development through epigenetic mechanisms. Adaptation to exercise involves sensor proteins detecting exercise-related signals, the processing of signals by signalling proteins and networks, and the regulation of the actual adaptations by effector proteins. Many sport- and exercise-related traits depend on both common and rare DNA sequence variations, including the muscle mass-increasing myostatin (GDF8) loss-of-function and the haematocrit-increasing EPOR gain-of-function mutations. Additionally, common DNA sequence variations contribute to the inherited variability of development, body height, strength, and endurance. Finally, in addition to ethical concerns, current genetic performance tests only explain a fraction of the variation of sport and exercise-related traits.
The influence of physical activity and training on growth and maturation
Authors: Malina Robert M
Published: April 2017

Physical activity in the general youth population and systematic training for sport among young athletes seems to have no effect on size attained and rate of growth in height, or on maturity status and timing. However, activity and training may influence body weight and composition. While both favourably influence bone mineral, variable effects are noted in some sports. Activity has a minimal effect on fatness in normal weight youth, but regular training generally has a positive influence on fatness in youth athletes. Data for fat-free/lean tissue mass are suggestive, but limited. Constitutional factors play a central role in the selection and retention of young athletes in a sport.