bluuebunny/crossref_metadata_2025 huggingface dataset:
The Prevalence of Depressive and Anxiety Symptoms in Student-Athletes and the Relationship With Resilience and Help-Seeking Behavior
Authors: Drew Breanna , Matthews James
Published: May 2018

The purpose of this study was to investigate the prevalence of depressive and anxiety symptoms within student-athletes and to examine protective factors which may act as a buffer against mental ill-health. A cross-sectional design was employed. A sample of 185 student-athletes (M = 20.77; SD = .50; 35% female) agreed to take part. Participants completed measures of depression, anxiety, psychological resilience and formal and informal help-seeking behavior. Thirty one percent of student-athletes reported moderate to severe symptoms of depression and/or anxiety. Student-athletes who reported requiring professional help for problems were more likely to record moderate to severe symptoms of depression and anxiety. Student-athletes who did not seek informal support were more likely to report symptom levels for depression outside the normal range. Higher resilience scores were associated with lower symptom reporting for both depression and anxiety. Practical implications for supporting student-athletes’ mental health across institutional, interpersonal and intrapersonal levels are discussed.
Mindful Sport Performance Enhancement: Randomized Controlled Trial of a Mental Training Program With Collegiate Athletes
Authors: Glass Carol R. , Spears Claire A. , Perskaudas Rokas , Kaufman Keith A.
Published: May 2018

College is a stressful time for many students, including student-athletes, who may benefit from mindfulness interventions focusing on present-moment awareness and nonjudgmental acceptance. Mindful sport performance enhancement (MSPE) has shown promise in previous open trials for promoting both athlete well-being and psychological factors related to sport performance, and this first randomized controlled trial of MSPE was conducted with mixed-sport groups of 52 NCAA Division III student-athletes. Each of the six sessions included educational, discussion-based, experiential, and home practice components, with meditation exercises progressing from sedentary mindfulness to mindfulness in motion. Whereas wait-list controls showed significant increases in depressive symptoms, those who received MSPE evidenced non-significant reductions in depressive symptoms over the course of treatment. Furthermore, once controls had also received MSPE, treatment completers (the 41% who attended at least five of six MSPE sessions) demonstrated significant increases in flow, trait mindfulness, satisfaction with life, and self-rated sport performance, along with reductions in worry, with medium to large effect sizes. There were no significant changes for treatment completers from post-treatment to 6-month follow-up, suggesting that improvements were maintained over time.
Relationship Between Motivational Climate to Body Esteem and Social Physique Anxiety Within College Physical Activity Classes
Authors: Miller Sheryl , Fry Mary
Published: May 2018

The purpose of this study was to examine the relationship of students’ perceptions of the motivational climate in their university exercise class to their body esteem (BE) and social physique anxiety (SPA). Students in physical activity classes at a Midwestern university completed a survey measuring their perceptions of the caring, task- and ego-involving features of the exercise class climate, BE (i.e., weight and appearance), and SPA. Canonical correlation analysis revealed one significant function for males and females. Loadings revealed males’ perceptions of a highly caring and task-involving climate with low emphasis on ego-involving climate features were associated with higher weight and appearance BE and lower SPA. Females were similar except the ego-involving climate did not significantly contribute to the model. Continued research may examine the link between motivational climate and BE, but mounting evidence suggests creating positive exercise environments is associated with participants’ adaptive responses, including BE and SPA.
Tunable quantum criticality and super-ballistic transport in a “charge” Kondo circuit
Authors: Iftikhar Z. , Anthore A. , Mitchell A. K. , Parmentier F. D. , Gennser U. , Ouerghi A. , Cavanna A. , Mora C. , Simon P. , Pierre F.
Published: May 2018

A nanostructure quantum simulator

Phase transitions occurring at absolute zero temperature, or quantum phase transitions (QPTs), can be grouped into broad categories called universality classes. The classification is based on the properties of the transition rather than the microscopic details of the underlying system. Iftikhar
et al.
exploited this fact to study QPTs in clean, tunable nanostructures, rather than in complex materials, where they most often occur. Within a single nanostructure, two different classes of QPTs with profoundly different characters were studied and comprehensively characterized.

Science
, this issue p.
1315
Evolution of pallium, hippocampus, and cortical cell types revealed by single-cell transcriptomics in reptiles
Authors: Tosches Maria Antonietta , Yamawaki Tracy M. , Naumann Robert K. , Jacobi Ariel A. , Tushev Georgi , Laurent Gilles
Published: May 2018

Evolution of the brain

Just how related are reptilian and mammalian brains? Tosches
et al.
used single-cell transcriptomics to study turtle, lizard, mouse, and human brain samples. They assessed how the mammalian six-layered cortex might be derived from the reptilian three-layered cortex. Despite a lack of correspondence between layers, mammalian astrocytes and adult neural stem cells shared evolutionary origins. General classes of interneuron types were represented across the evolutionary span, although subtypes were species-specific. Pieces of the much-folded mammalian hippocampus were represented as adjacent fields in the reptile brains.

Science
, this issue p.
881
Polyamide membranes with nanoscale Turing structures for water purification
Authors: Tan Zhe , Chen Shengfu , Peng Xinsheng , Zhang Lin , Gao Congjie
Published: May 2018

Turing structures at the nanoscale

Turing structures arise when imbalances in diffusion rates make a stable steady-state system sensitive to small heterogeneous perturbations. For example, Turing patterns occur in chemical reactions when a fast-moving inhibitor controls the motion of a slower-moving activator. Tan
et al.
grew polyamide membranes by using interfacial polymerization, where the reactions occur at the interface between oil and water layers. The addition of polyvinyl alcohol to the aqueous phase reduced the diffusion of the monomer. This process generates membranes with more bumps, voids, and islands, which prove to be better for water desalination.

Science
, this issue p.
518
Enhanced thermal stability of nanograined metals below a critical grain size
Authors: Zhou X. , Li X. Y. , Lu K.
Published: May 2018

Smaller but more thermally stable

Synthesizing metals with extremely small (nanoscale) grain sizes makes for much stronger materials. However, very small–grained materials start to coarsen at relatively low temperatures, wiping out their most desirable properties. Zhou
et al.
discovered a way to avoid this problem by mechanically grinding copper and nickel at liquid nitrogen temperatures. The processing method creates low-angle grain boundaries between the nanograins, which promotes thermal stability.

Science
, this issue p.
526
Effects of PslG on the Surface Movement of Pseudomonas aeruginosa
Authors: Zhang Jingchao , He Jing , Zhai Chunhui , Ma Luyan Z. , Gu Lichuan , Zhao Kun
Published: May 2018

PslG attracted a lot of attention recently due to its great potential abilities in inhibiting biofilms of
Pseudomonas aeruginosa
. However, how PslG affects biofilm development still remains largely unexplored. Here, we focused on the surface motility of bacterial cells, which is critical for biofilm development. We studied the effects of PslG on bacterial surface movement in early biofilm development at a single-cell resolution by using a high-throughput bacterial tracking technique. The results showed that compared with no exogenous PslG addition, when PslG was added to the medium, bacterial surface movement was significantly (4 to 5 times) faster and proceeded in a more random way with no clear preferred direction. A further study revealed that the fraction of walking mode increased when PslG was added, which then resulted in an elevated average speed. The differences of motility due to PslG addition led to a clear distinction in patterns of bacterial surface movement and retarded microcolony formation greatly. Our results provide insight into developing new PslG-based biofilm control techniques.

IMPORTANCE
Biofilms of
Pseudomonas aeruginosa
are a major cause for hospital-acquired infections. They are notoriously difficult to eradicate and pose serious health hazards to human society. So, finding new ways to control biofilms is urgently needed. Recent work on PslG showed that PslG might be a good candidate for inhibiting/disassembling biofilms of
Pseudomonas aeruginosa
through Psl-based regulation. However, to fully explore PslG functions in biofilm control, a better understanding of PslG-Psl interactions is needed. Toward this end, we examined the effects of PslG on the surface movement of
Pseudomonas aeruginosa
in this work. The significance of our work is in greatly enhancing our understanding of the inhibiting mechanism of PslG on biofilms by providing a detailed picture of bacterial surface movement at a single-cell level, which will allow a full understanding of PslG abilities in biofilm control and thus present potential applications in biomedical fields.
Do schoolbags cause back pain in children and adolescents? A systematic review
Authors: Yamato Tiê Parma , Maher Chris G , Traeger Adrian C , Wiliams Christopher M , Kamper Steve J
Published: May 2018

Objective

To investigate whether characteristics of schoolbag use are risk factors for back pain in children and adolescents.

Data sources

Electronic searches of MEDLINE, EMBASE and CINAHL databases up to April 2016.

Eligibility criteria for selecting studies

Prospective cohort studies, cross-sectional and randomised controlled trials conducted with children or adolescents. The primary outcome was an episode of back pain and the secondary outcomes were an episode of care seeking and school absence due to back pain. We weighted evidence from longitudinal studies above that from cross-sectional. The risk of bias of the longitudinal studies was assessed by a modified version of the Quality in Prognosis Studies tool.

Results

We included 69 studies (n=72 627), of which five were prospective longitudinal and 64 cross-sectional or retrospective. We found evidence from five prospective studies that schoolbag characteristics such as weight, design and carriage method do not increase the risk of developing back pain in children and adolescents. The included studies were at moderate to high risk of bias. Evidence from cross-sectional studies aligned with that from longitudinal studies (ie, there was no consistent pattern of association between schoolbag use or type and back pain). We were unable to pool results due to different variables and inconsistent results.

Summary/conclusion

There is no convincing evidence that aspects of schoolbag use increase the risk of back pain in children and adolescents.
A long way to go: a systematic review to assess the utilisation of sexual and reproductive health services during humanitarian crises
Authors: Singh Neha S , Aryasinghe Sarindi , Smith James , Khosla Rajat , Say Lale , Blanchet Karl
Published: May 2018

Introduction

Women and girls are affected significantly in both sudden and slow-onset emergencies, and face multiple sexual and reproductive health (SRH) challenges in humanitarian crises contexts. There are an estimated 26 million women and girls of reproductive age living in humanitarian crises settings, all of whom need access to SRH information and services. This systematic review aimed to assess the utilisation of services of SRH interventions from the onset of emergencies in low- and middle-income countries.

Methods

We searched for both quantitative and qualitative studies in peer-reviewed journals across the following four databases: EMBASE, Global Health, MEDLINE and PsychINFO from 1 January 1980 to 10 April 2017. Primary outcomes of interest included self-reported use and/or confirmed use of the Minimum Initial Service Package services and abortion services. Two authors independently extracted and analysed data from published papers on the effect of SRH interventions on a range of SRH care utilisation outcomes from the onset of emergencies, and used a narrative synthesis approach.

Results

Of the 2404 identified citations, 23 studies met the inclusion criteria. 52.1% of the studies (n=12) used quasi-experimental study designs, which provided some statistical measure of difference between intervention and outcome. 39.1% of the studies (n=9) selected were graded as high quality, 39.1% moderate quality (n=9) and 17.4% low quality (n=4). Evidence of effectiveness in increasing service utilisation was available for the following interventions: peer-led and interpersonal education and mass media campaigns, community-based programming and three-tiered network of community-based reproductive and maternal health providers.

Conclusions

Despite increased attention to SRH service provision in humanitarian crises settings, the evidence base is still very limited. More implementation research is required to identify interventions to increase utilisation of SRH services in diverse humanitarian crises settings and populations.
Charlie Gard: in defence of the law
Authors: Close Eliana , Willmott Lindy , White Benjamin P
Published: May 2018

Much of the commentary in the wake of the Charlie Gard litigation was aimed at apparent shortcomings of the law. These include concerns about the perceived inability of the law to consider resourcing issues, the vagueness of the best interests test and the delays and costs of having disputes about potentially life-sustaining medical treatment resolved by the courts. These concerns are perennial ones that arise in response to difficult cases. Despite their persistence, we argue that many of these criticisms are unfounded. The first part of this paper sets out the basic legal framework that operates when parents seek potentially life-sustaining treatment that doctors believe is against a child’s best interests, and describes the criticisms of that framework. The second part of the paper suggests an alternative approach that would give decision-making power to parents, and remove doctors’ ability to unilaterally withhold or withdraw life-sustaining treatment that they regard is futile. This proposal is grounded in several values that we argue should guide these regulatory choices. We also contend that the best interests test is justifiable and since the courts show no sign of departing from it, the focus should be on how to better elucidate the underlying values driving decisions. We discuss the advantages of our proposed approach and how it would address some of the criticisms aimed at the law. Finally, we defend the current role that the judiciary plays, as an independent state-sanctioned process with a precedent-setting function.
Why Charlie Gard’s parents should have been the decision-makers about their son’s best interests
Authors: Gillon Raanan
Published: May 2018

This paper argues that Charlie Gard’s parents should have been the decision-makers about their son’s best interests and that determination of Charlie’s best interests depended on a moral decision about which horn of a profound moral dilemma to choose. Charlie’s parents chose one horn of that moral dilemma and the courts, like Charlie Gard’s doctors, chose the other horn. Contrary to the first UK court’s assertion, supported by all the higher courts that considered it, that its judgement was ‘objective’, this paper argues that the judgement was not and could not be ‘objective’ in the sense of objectively correct but was instead a value judgement based on the judge’s choice of one horn of the moral dilemma. While that horn was morally justified so too was the horn chosen by the parents. The court could and should have avoided depriving the parents of their normal moral and legal right and responsibility to decide on their child’s best interests. Instead, this paper argues that the court should have acknowledged the lawfulness of both horns of the moral dilemma and added to its judgement that Charlie Gard’s doctors were not legally obliged to provide treatment that they believed to be against their patient’s best interests the additional judgement that Charlie’s parents could lawfully transfer his care to other doctors prepared to offer the infant a trial of the experimental treatment requested by his parents.
Co-design of water services and infrastructure for Indigenous Canada: A scoping review
Authors: Bradford Lori E.A. , Vogel Tim , Lindenschmidt Karl-Erich , McPhedran Kerry , Strickert Graham E.H. , Fonstad Terrence A. , Bharadwaj Lalita A.
Published: May 2018

There is movement in engineering fields and in Indigenous communities for enhancement of local participation in the design of community infrastructure. Inclusion of community priorities and unique cultural, spiritual, and traditional values harmonize the appearance, location, and functionality of developments with the social and cultural context in which they are built and contribute to holistic wellness. However, co-design processes that align community values and the technical needs of water facilities are difficult to find. A scoping review was conducted to explore the state of knowledge on co-design of water infrastructure in Indigenous Canada to build a knowledge base from which practices and processes could emerge. The scoping results revealed that articles and reports emerged only in recent years, contained case studies and meta-reviews with primary (qualitative) data, and involved community members in various capacities. Overall, 13 articles were reviewed that contributed to understanding co-design for water infrastructure in Indigenous Canada. Barriers to co-design included funding models for Indigenous community infrastructure, difficulties in engineers and designers understanding Indigenous worldviews and paradigms, and a lack of cooperation among stakeholders that contribute to ongoing design failures. A working definition of co-design for Indigenous water infrastructure is presented.
The first two coefficients of the Bergman function expansions for Cartan–Hartogs domains
Authors: Feng Zhiming
Published: May 2018

Let [Formula: see text] be a globally defined real Kähler potential on a domain [Formula: see text], and [Formula: see text] be a Kähler metric on the Hartogs domain [Formula: see text] associated with the Kähler potential [Formula: see text]. First, we obtain explicit formulas of the coefficients [Formula: see text] of the Bergman function expansion for the Hartogs domain [Formula: see text] in a momentum profile [Formula: see text]. Second, using explicit expressions of [Formula: see text], we obtain necessary and sufficient conditions for the coefficients [Formula: see text] to be constants. Finally, we obtain all the invariant complete Kähler metrics on Cartan–Hartogs domains such that their the coefficients [Formula: see text] of the Bergman function expansions are constants.
Modular curves and symmetries of Hecke type
Authors: Heim Bernhard , Kaiser Christian , Murase Atsushi
Published: May 2018

We give a characterization of modular curves by a single symmetry of Hecke type. In the proof, we use the theorem of André, which characterizes modular curves in terms of special points.
Constraint consensus of heterogeneous multi-agent systems
Authors: Liang Quanyi , She Zhikun
Published: May 2018

In this brief paper, we study the constraint consensus problem of heterogeneous multi-agent systems. First, we provide an invariant set, which can be exactly obtained by solving linear equations. Then, a virtual system is defined on this invariant set such that it is the largest common embedded system of all the individual agents. Afterwards, a linear consensus protocol is proposed with the corresponding constraint consensus criterion. In particular, the above virtual system can reveal all the asymptotic dynamical behaviors if heterogeneous multi-agent systems achieve consensus. Finally, an example with numerical simulations is given to illustrate the validity of our criterion.
Glueball spectra from a matrix model of pure Yang–Mills theory
Authors: Acharyya Nirmalendu , Balachandran A. P. , Pandey Mahul , Sanyal Sambuddha , Vaidya Sachindeo
Published: May 2018

We present variational estimates for the low-lying energies of a simple matrix model that approximates SU(3) Yang–Mills theory on a three-sphere of radius R. By fixing the ground state energy, we obtain the (integrated) renormalization group (RG) equation for the Yang–Mills coupling g as a function of R. This RG equation allows to estimate the mass of other glueball states, which we find to be in excellent agreement with lattice simulations.
The size seems to matter or where lies the “asymptopia”?
Authors: Petrov V. A. , Okorokov V. A.
Published: May 2018

We discuss an apparent correlation between the onset of the rising regime for the total cross-sections and the slowdown of the rise of the forward slopes with energy. It is shown that even at highest energies achieved with the large hadron collider (LHC) the proper sizes of the colliding protons comprise the bulk of the interaction region. This seems to witness that the “asymptopia” — a hypothetical “truly asymptotic” regime — lies at energies no less than [Formula: see text] (100 TeV). In the course of reasoning, we also discuss the question of the dependence of the effective sizes of hadrons in collision on the type of their interaction.
Damping of spin waves in high-Tc superconductors in the spin polaron formulation
Authors: Ong Perkins Jon , Yanga Danilo M.
Published: May 2018

The damping of spin waves in high-T[Formula: see text] superconductors is investigated in this paper. We use the spin polaron formulation in the finite temperature (Matsubara) Green’s function method in a representation, where holes are described as spinless fermions (holons) and spins as normal bosons characterized by the hard-core bosonic operators in accordance with the Holstein–Primakoff transformation. The interaction of holes with spin waves is then described by a Hamiltonian, which resembles the conventional polaron problem and came to be known as the spin polaron Hamiltonian. The rate of the damping of spin waves is then obtained from the self-energy term of the spin wave Green’s function at finite temperature. In the limit of zero temperature and low frequency, the spin wave damping was subsequently determined. We evaluated the same quantity by analytic continuation to get the zero temperature result.
Roles of degree, H-index and coreness in link prediction of complex networks
Authors: Zhu Xuzhen , Yang Yujie , Li Lanxi , Cai Shimin
Published: May 2018

Link prediction based on topological similarity attracts more and more interests. Traditionally, researchers almost focus on utility of the paths between two unlinked endpoints, but pay little attention to the influence of the endpoints with only degree considered. Through profound investigations, we find, besides of degree, H-index and coreness also can play important roles in link prediction as the influence of endpoint especially in models based on representative SRW which is for the first time introduce influence into link prediction. In this paper, we mainly research degree, H-index and coreness in SRW-based models to explore their roles in accurate link prediction. Extensive experiments on twelve real benchmark datasets suggest that in most cases H-index serves as a better tradeoff in accurate link prediction than either degree or coreness.
Spatial-Structure Siamese Network for Plant Identification
Authors: Gao Zhi-Yong , Xie Heng-Xing , Li Ji-Feng , Liu Shi-Li
Published: May 2018

Plant identification is now attracting considerable attention due to its important applications in agriculture automation and ecosystems. Recently, deep learning-based plant identification methods have drawn increasing interest and shown favorable performance. However, existing methods do not consider plant spatial structure and their similarities explicitly. In this paper, we propose a robust spatial-structure siamese network (3SN) for plant identification, which has the following advantages: (1) It models the spatial structure of a plant by recurrent neural networks exploiting their capability to capture long-range dependencies among sequential data, which enables it to capture even a slight difference between a specific plant and distractors. (2) The plant similarity modeling is achieved effectively by a siamese network with large numbers of image pairs. In this way, the plant classification task and siamese learning task are learned jointly in a unified framework, where both can enhance and complement each other. Extensive experimental results show that the proposed 3SN method outperforms the state-of-the-art methods consistently.
Fuzzy Logic-Based Pulse Density Modulation Scheme for Mitigating Uncertainties in AC–AC Resonant Converter Aided Induction Heating System
Authors: Vishnuram Pradeep , Ramasamy Sridhar
Published: May 2018

Induction heating (IH) applications aided by power electronic control system have become very attractive in the recent past. The power electronics circuits succumb to severe switching loss, lower power density if proper switching methodology is not adhered. A state of uncertainty is indispensable in IH application as the power required by the load varies depending upon the nature of work piece. This uncertain issue makes the selection of the control algorithm and controller very vital. The mundane controllers may not be compatible to combat the uncertainties and leads to exhibit dynamic problems say transients, peak overshoot and poor response. Henceforth, the IH system requires a superlative converter topology and control scheme in order to have reduced switching loss and to improve the system performance there by negating the uncertainties. Here, in this work, a direct AC–AC boost resonant converter fed by pulse density modulation (PDM) is realized in a single stage mode. A fuzzy logic-based PDM control technique improves the efficiency and provides the versatile power control with reduced time domain specifications for dynamic changes in load. The proposed system has been studied using MATLAB/SIMULINK and validated using a hardware prototype employing dsPIC30F4011 microcontroller. The results reveal that efficient control over power can be accomplished by varying the density of the switching pulses, and thereby the efficiency is enhanced even with reduced component count. Also, the single-stage conversion is effective than its two-stage counterpart.
An Evolutionary Game Theory Strategy for Carbon Emission Reduction in the Electricity Market
Authors: Perera Ryle S.
Published: May 2018

We study how a government can manage a policy of environmental sustainability in a competitive electricity market. We assume that the government plays a Stackelberg game as leader, to study the evolutionary stable equilibria of the problem under this game theory paradigm. We then analyze a bimatrix coordination game to have many equilibria when no single power plant has incentives to deviate when the others reduce carbon emissions. In fact for power plants the adapted behavior is to avoid heavy tariffs, preserve the market share and minimize the environmental impact. We use the notion of quantal response equilibrium (QRE) in the case of bounded rationality to obtain a unique Nash equilibrium known as the centroid-dominant equilibrium of the game. This proposed quantitative framework can be applied by policy makers to determine incentives and tariffs to meet the environmental obligations in the electricity market.
Simulation of Vortex-Induced Vibration of Long-Span Bridges: A Nonlinear Normal Mode Approach
Authors: Xu Kun , Ge Yaojun , Zhao Lin , Du Xiuli
Published: May 2018

Due to the lack of analytic technique for simulating the vortex-induced vibration (VIV) of long-span bridges, a combination of the VIV semi-empirical model with the structural equation of motion is widely employed to calculate the responses of bridge structures. However, the applicability of this method has seldom been investigated before. In this study, the theoretical defects of the conventional combination strategy (i.e. the finite element procedure or the linear normal mode procedure, LNM) are first discussed, a more theoretically reliable approach (the nonlinear norm mode approach, NNM) is then proposed, and the closed-form expression for the NNM of the VIV system is derived. The accuracy of the proposed method is further illustrated by two case studies. This new approach offers a theoretically reliable tool for analyzing the VIV of long-span bridges. It can also be applied to the process of VIV fatigue analysis or control strategy optimization.
Changes in the role of energy conditions in f(R) cosmology by the acceleration of universe
Authors: Sepehri Alireza , Shoorvazi Somayeh , Ghaforyan Hossein
Published: May 2018

Recently, the role of energy conditions in [Formula: see text]-cosmology has been investigated. We generalize these results to BIonic systems in accelerating systems and show that the energy conditions can be changed in this system. We show that [Formula: see text]-gravity produces a wormhole between two universes and forms a BIonic system. On the other hand, the acceleration creates two regions in the Rindler space-time which BIon in each region acts reverse to other in another region. This means that by the expansion of universes of the BIon in one region, universes of another BIon in other regions contract. Also, in this model, by increasing the order of curvatures in [Formula: see text]-gravity, the energy and the entropy of system in one region increases and in other region decreases. Amount of this growth or decrease in the energy depends on the acceleration of universes. Finally, by calculating the dark energy equation of state, we observe that one universe enters to phantom phase and goes toward the big rip singularity and another goes out of phantom state.
Stress Wave Propagation Analysis in One-Dimensional Micropolar Rods with Variable Cross-Section Using Micropolar Wave Finite Element Method
Authors: Mirzajani Mohsen , Khaji Naser , Hori Muneo
Published: May 2018

The wave finite element method (WFEM) is developed to simulate the wave propagation in one-dimensional problem of nonhomogeneous linear micropolar rod of variable cross-section. For this purpose, two kinds of waves with fast and slow velocities are detected. For micropolar medium, an additional rotational degree of freedom (DOF) is considered besides the classical elasticity’s DOF. The proposed method is implemented to solve the wave propagation, reflection and transmission of two distinct waves and impact problems in micropolar rods with different layers. Along with new solutions, results of the micropolar wave finite element method (MWFEM) are compared with some numerical and/or analytical solutions available in the literature, which indicate excellent agreements between the results.
Recent advances in karst research: from theory to fieldwork and applications
Authors: Parise Mario , Gabrovsek Franci , Kaufmann Georg , Ravbar Natasa
Published: May 2018

Karst landscapes and karst aquifers, which are composed of a variety of soluble rocks such as salt, gypsum, anhydrite, limestone, dolomite and quartzite, are fascinating areas of study. As karst rocks are abundant on the Earth's surface, the fast evolution of karst landscapes and the rapid flow of water through karst aquifers present challenges from a number of different perspectives. This collection of 25 papers deals with different aspects of these challenges, including karst geology, geomorphology and speleogenesis, karst hydrogeology, karst modelling, and karst hazards and management. Together these papers provide a state-of-the-art review of the current challenges and solutions in describing karst from a scientific perspective.
Exploration and development in the Carboniferous of the Southern North Sea: a 30-year retrospective
Authors: Besly Bernard
Published: May 2018

A review is presented of the progress of exploration for, and development of, gas fields in the Carboniferous of the UK Southern North Sea in the period since the first significant discoveries were made in 1984. The outcomes of such exploration have generally failed to live up to high initial expectations and exploration targeting of the Carboniferous has declined, the objective having come to be seen by many as difficult and risky. This review includes a summary of the published consensus regarding elements of the Carboniferous petroleum system and discusses the reasons for the decline in interest, which encompass geological complexity, interpretational and operational problems and other non-technical factors. Five areas of Carboniferous petroleum geology are identified in which the currently accepted status quo is open to challenge. More detailed discussion of these leads to the following general conclusions: (1) the distribution of source rocks and their maturation history remains poorly understood, largely as a result of the hitherto unquestioned acceptance that Westphalian coals have acted as the dominant gas source; (2) in many early wells the combination of formation damage and shortcomings in petrophysical data acquisition and evaluation has resulted in a failure to identify potential pay in low permeability formations and an overemphasis on the importance of channel sand bodies as reservoir objectives; (3) the controls on seal capacity and integrity within the Carboniferous succession have been little studied and, as a result, an unduly pessimistic view of intra-Carboniferous sealing potential has prevailed; (4) the distribution of sub-basin depocentres, and thus of basinal shale source rocks and potential hydrocarbon migration paths, remains poorly understood; and (5) conceptual models of the large-scale tectonic history of the Carboniferous basin complex have failed to evolve from early and simplistic rift and sag models, which do not adequately explain the observed distribution of stratigraphic thicknesses and are inconsistent with some published burial histories.
Revised stratigraphic framework of pre-Westphalian Carboniferous petroleum system elements from the Outer Moray Firth to the Silverpit Basin, North Sea, UK
Authors: Kearsey T. I. , Millward D. , Ellen R. , Whitbread K. , Monaghan A. A.
Published: May 2018

Spatially and temporally variable Tournaisian to Namurian Carboniferous fluvial, fluvio-deltaic, platform carbonate and shale-dominated basin sedimentary successions up to 3.5 km thick are preserved in a complex series of basins from the Outer Moray Firth (Quadrant 14) to the Silverpit Basin (Quadrant 44). Differences in stratigraphic nomenclature in the areas surrounding the Mid North Sea High and onshore, combined with sparse biostratigraphic data, have hindered the systematic regional understanding of the timing and controls on stacked source and reservoir rock intervals. Over 125 well reinterpretations, tied to seismic interpretations, provide evidence of the inception and extent of a delta system. Regional time slices highlight a long-lived laterally equivalent basinal, mud-rich succession across Quadrants 41–44. They also show that the area from the Outer Moray Firth to the Silverpit Basin was part of the same sedimentary system up to at least Namurian times. All of this is placed within a simplified stratigraphic framework.
Sediment mass movement of a particle-laden turbidity current based on ultrasound velocity profiling and the distribution of sediment concentration
Authors: Nomura Shun , Hitomi Jumpei , De Cesare Giovanni , Takeda Yasushi , Yamamoto Yuzuru , Sakaguchi Hide
Published: May 2018

Particle-laden flows or turbidity currents along the seafloor are important to the formation and erosion of submarine topography. To understand the mass-transport process, flume tests were carried out with a continuous supply of quartz-laden suspension. The vertical and horizontal velocities were extracted by two pairs of ultrasound Doppler velocity profilers installed at different angles with respect to the bed-normal direction. Due to the head intrusion into the ambient water, the sediment in the suspension was continuously lifted up and mixed, leaving lobes and clefts. The velocity-maximum layer acted as the main sediment conveyor and divided the body into wall and jet regions. The concentration distribution was also quantified based on the relationship between the fluid density and the intensity of light attenuation obtained using a video recording. An area of high sediment concentration was observed just behind the head frontal area. Analysis of the velocity and concentration distribution demonstrated that sediment in the turbidity current was transported mainly by head movement and that continuous sedimentation took place in the wall region. The results indicate that a turbidity current proceeds while maintaining an ordered inner dynamic structure.
Stratal architecture and evolution of a slope mass-transport complex, Isaac Formation, Neoproterozoic Windermere Supergroup, southern Canadian Cordillera, British Columbia, Canada
Authors: Navarro Lilian , Arnott R. William C.
Published: May 2018

Detailed sedimentological and stratigraphic analyses of a
c.
1500 m thick, siliciclastic-dominated slope succession in the Neoproterozoic Isaac Formation at the Castle Creek study area (southern Canadian Cordillera) reveals the occurrence of four well-preserved mass-transport complexes (MTCs) composed principally of slide/slump and debris-flow deposits. The stratigraphically lowest of these complexes is about 60 m thick and crops out for >2.5 km laterally, consisting of slide and debrite. The slide has an irregular erosive base with ramp-and-flat geometry. This is overlain locally by boulder-sized blocks of slightly to moderately deformed strata, bounded by shear surfaces. The slide is overlain by a debrite that pinches and swells laterally, consisting of matrix-supported conglomerate with common metre-scale clasts of mudstone and coarse-grained sandstone embedded in a mudstone-rich matrix with dispersed, pebble quartz grains. Based on its stratigraphic position at the base of the slope, vertical stacking of slide-debrite, lithological distribution, considerable thickness and lateral extent, this MTC is interpreted to be associated with a major episode of continental slope instability and submarine mass-wasting. The close association between the MTC and underlying/overlying mixed carbonate-siliciclastic strata suggests that sea level most likely exerted a key control on sediment supply, which ultimately led to the emplacement of this MTC.
Three modes of isograd formation in the northern Monashee Complex of the Canadian Cordillera
Authors: Gervais Félix
Published: May 2018

This contribution re-examines textural relationships in metapelitic schist from five metamorphic zones separated by four isograds along the west flank of the Frenchman Cap dome in the southeastern Canadian Cordillera. There is a muscovite-out isograd formed by muscovite-dehydration melting in the kyanite-field. Two others, including one coinciding with the muscovite-out isograd, mark the appearance of sillimanite, which was produced along with biotite by garnet breakdown in the presence of melt. Two others mark the disappearance of kyanite: one formed during retrogression, the other coinciding with a shear zone (the Monashee décollement). Only the muscovite-out isograd, therefore, corresponds with the classical definition of an intersection of the topography with a prograde, isogradic-surface. This contribution exemplifies the need to use a descriptive definition of isograd as the trace of a surface across which a specific change in metamorphic mineralogy takes place. It is further proposed to specify their origin whenever possible with terms such as prograde-, retrograde- and structural-isograds. This revised terminology for isograds will improve our understanding of metamorphic terrains by helping to localize cryptic shear zones, gain a better understanding of the retrograde path and put firmer constraints on viable tectonic models.
The role of noncoding RNAs in regulating epithelial responses in COPD
Authors: Chen Yifan , Thomas Paul S. , Kumar Rakesh K. , Herbert Cristan
Published: May 2018

Chronic obstructive pulmonary disease (COPD), one of the leading causes of death in the world, is a chronic inflammatory disease of the airways usually caused by long-term exposure to inhaled irritants. Airway epithelial cells (AECs) play a key role in initializing COPD and driving the exacerbation of this disease through the release of various cytokines. This AEC-derived cytokine response is tightly regulated possibly through the regulatory effects of noncoding RNAs (ncRNAs). Although the importance of ncRNAs in pulmonary diseases has been increasingly realized, little is known about the role of ncRNA in the regulation of inflammatory responses in COPD. This review outlines the features of AEC-derived cytokine responses in COPD and how ncRNAs regulate these inflammatory responses.
Inhibition of Raf1 ameliorates bleomycin-induced pulmonary fibrosis through attenuation of TGF-β1 signaling
Authors: Li Shuang , Liu Jia , Tan Jiangning , Li Lian , Kaltreider Mary J. , Zhao Jing , Kass Daniel J. , Shang Dong , Zhao Yutong
Published: May 2018

Idiopathic pulmonary fibrosis (IPF) is a fatal fibrotic lung disease associated with aberrant activation and differentiation of fibroblasts, leading to abnormal extracellular matrix production. Currently, it is still an untreatable disease (except for lung transplantation). Here, we demonstrate that the Raf1 inhibitor GW5074 ameliorates lung fibrosis in bleomycin-induced pulmonary fibrosis. Posttreatment with GW5074 reduced fibronectin (FN) expression, collagen deposition, and inflammatory cell infiltration in bleomycin-challenged mice, suggesting an antifibrotic property of GW5074. To determine the molecular mechanisms by which inhibition of Raf1 ameliorates lung fibrosis, we investigated the role of Raf1 in TGF-β1 signaling in human lung fibroblasts. GW5074 or downregulation of Raf1 by siRNAs significantly attenuated TGF-β1-induced smooth muscle actin, FN, and collagen I expression, whereas overexpression of Raf1 promoted the effects of TGF-β1 in lung fibroblasts. Furthermore, we found that Raf1-promoted TGF-β1 signaling was through the Raf1/ERK/Smad pathway and contributed to the cell proliferation and migration in human lung fibroblasts. This study provides preclinical and mechanistic evidence for development of Raf1 inhibitors as potential antifibrotic drugs for the treatment of IPF.
miR-142-3p is associated with aberrant WNT signaling during airway remodeling in asthma
Authors: Bartel Sabine , Carraro Gianni , Alessandrini Francesca , Krauss-Etschmann Susanne , Ricciardolo Fabio Luigi Massimo , Bellusci Saverio
Published: May 2018

Asthma is characterized by a chronic inflammation and remodeling of the airways. Although inflammation can be controlled, therapeutic options to revert remodeling do not exist. Thus, there is a large and unmet need to understand the underlying molecular mechanisms to develop novel therapies. We previously identified a pivotal role for miR-142-3p in regulating airway smooth muscle (ASM) precursor cell proliferation during lung development by fine-tuning the Wingless/Integrase I (WNT) signaling. Thus, we here aimed to investigate the relevance of this interaction in asthma. We performed quantitative RT-PCR and immune staining in a murine model for ovalbumin-induced allergic airway inflammation and in bronchial biopsies from patients with asthma and isolated primary fibroblasts thereof. miR-142-3p was increased in hyperproliferative regions of lung in murine and human asthma, whereas this microRNA (miRNA) was excluded from regions with differentiated ASM cells. Increases in miR-142-3p were associated with a decrease of its known target Adenomatous polyposis coli. Furthermore, we observed a differential expression of miR-142-3p in bronchial biopsies from patients with early or late onset severe asthma, which coincided with a differential WNT signature. Our data suggest that miR-142-3p is involved in regulating the balance between proliferation and differentiation of ASM cells in asthma, possibly via controlling WNT signaling. Thus, this miRNA might be an interesting target to prevent ASM hyperproliferation in asthma.
Long-term culture and cloning of primary human bronchial basal cells that maintain multipotent differentiation capacity and CFTR channel function
Authors: Peters-Hall Jennifer R. , Coquelin Melissa L. , Torres Michael J. , LaRanger Ryan , Alabi Busola R. , Sho Sei , Calva-Moreno Jose F. , Thomas Philip J. , Shay Jerry W.
Published: May 2018

While primary cystic fibrosis (CF) and non-CF human bronchial epithelial basal cells (HBECs) accurately represent in vivo phenotypes, one barrier to their wider use has been a limited ability to clone and expand cells in sufficient numbers to produce rare genotypes using genome-editing tools. Recently, conditional reprogramming of cells (CRC) with a Rho-associated protein kinase (ROCK) inhibitor and culture on an irradiated fibroblast feeder layer resulted in extension of the life span of HBECs, but differentiation capacity and CF transmembrane conductance regulator (CFTR) function decreased as a function of passage. This report details modifications to the standard HBEC CRC protocol (Mod CRC), including the use of bronchial epithelial cell growth medium, instead of F medium, and 2% O2, instead of 21% O2, that extend HBEC life span while preserving multipotent differentiation capacity and CFTR function. Critically, Mod CRC conditions support clonal growth of primary HBECs from a single cell, and the resulting clonal HBEC population maintains multipotent differentiation capacity, including CFTR function, permitting gene editing of these cells. As a proof-of-concept, CRISPR/Cas9 genome editing and cloning were used to introduce insertions/deletions in CFTR exon 11. Mod CRC conditions overcome many barriers to the expanded use of HBECs for basic research and drug screens. Importantly, Mod CRC conditions support the creation of isogenic cell lines in which CFTR is mutant or wild-type in the same genetic background with no history of CF to enable determination of the primary defects of mutant CFTR.