bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalência de sinais radiográficos de impacto femoroacetabular em indivíduos assintomáticos e não atletas
Authors: Garcia André , Gobetti Murilo , Tatei Anderson , Falótico Guilherme , Arliani Gustavo , Puertas Eduardo
Published: March 2018

O impacto femoroacetabular foi descrito como uma variação anatômica do fêmur proximal e/ou da borda acetabular, causa impacto na articulação do quadril. Uma parcela da população assintomática quanto ao quadril pode apresentar alterações radiográficas de impacto femoroacetabular. O objetivo do estudo é avaliar a prevalência desses sinais em indivíduos do sexo masculino assintomáticos e sedentários.

Estudo clínico, observacional, primário, transversal, controlado. Foram selecionados 32 voluntários masculinos, de 18 a 40 anos, assintomáticos quanto ao quadril, sedentários, atendidos em um Pronto-Socorro de Ortopedia de Hospital Universitário. Todos fizeram radiografias anteroposteriores da pelve padronizadas. Foram analisadas as medidas de ângulo alfa, índice de retroversão, sinal da espinha isquiática e sinal da parede posterior.

A média de idade foi de 29 anos (18–40). A prevalência de sinais radiográficos de impacto femoroacetabular com o uso do ângulo alfa de 67o foi de 53,1%; com o ângulo alfa de 82o, essa prevalência foi de 31,2%. A média do ângulo alfa foi de 67o (52,4–88,2o), 35,9% dos quadris foram classificados como limítrofes e 6,3% como patológicos. A média do ângulo alfa para o lado direito foi de 67,5o (52,5–88,2o) e para o esquerdo, 66,6o (53,1–86,9o). O índice de retroversão médio foi de 0,048 (lado direito – 0,044 e lado esquerdo – 0,052). O sinal da espinha foi positivo em 15,6% e da parede posterior em 20,3%.

O presente estudo demonstrou que a prevalência de sinais radiográficos numa população de homens adultos, assintomáticos e sedentários foi elevada (31,2%). O real significado clínico desse achado ainda carece de novos estudos.
Infectious mononucleosis - not always a benign condition: a case report of infectious mononucleosis–associated acute acalculous cholecystitis
Authors: Cameron Andrew , Akilan Kosalan , Carr David
Published: March 2018

Infectious mononucleosis is typically a self-limited viral infection of adolescence and early adulthood that resolves in a period of weeks, causing no major sequelae. We describe a case of a healthy 18-year-old female diagnosed with infectious mononucleosis who also presented with right upper quadrant abdominal pain, moderate transaminitis, and cholestatic biochemistry. An ultrasound revealed acute acalculous cholecystitis, generally a condition seen in the context of critical illness. Further investigating emergency department patients with infectious mononucleosis is often not indicated, but may be important for those who present atypically.
Turbulence dynamics in separated flows: the generalised Kolmogorov equation for inhomogeneous anisotropic conditions
Authors: Mollicone J.-P. , Battista F. , Gualtieri P. , Casciola C. M.
Published: March 2018

The generalised Kolmogorov equation is used to describe the scale-by-scale turbulence dynamics in the shear layer and in the separation bubble generated by a bulge at one of the walls in a turbulent channel flow. The second-order structure function, which is the basis of such an equation, is used as a proxy to define a scale-energy content, that is an interpretation of the energy associated with a given scale. Production and dissipation regions and the flux interchange between them, in both physical and separation space, are identified. Results show how the generalised Kolmogorov equation, a five-dimensional equation in our anisotropic and strongly inhomogeneous flow, can describe the turbulent flow behaviour and related energy mechanisms. Such complex statistical observables are linked to a visual inspection of instantaneous turbulent structures detected by means of the Q-criterion. Part of these turbulent structures are trapped in the recirculation where they undergo a pseudo-cyclic process of disruption and reformation. The rest are convected downstream, grow and tend to larger streamwise scales in an inverse cascade. The classical picture of homogeneous isotropic turbulence in which energy is fed at large scales and transferred to dissipate at small scales does not simply apply to this flow where the energy dynamics strongly depends on position, orientation and length scale.
Mechanisms of dispersion in a porous medium
Authors: Dentz M. , Icardi M. , Hidalgo J. J.
Published: March 2018

This paper studies the mechanisms of dispersion in the laminar flow through the pore space of a three-dimensional porous medium. We focus on preasymptotic transport prior to the asymptotic hydrodynamic dispersion regime, in which solute motion may be described by the average flow velocity and a hydrodynamic dispersion coefficient. High-performance numerical flow and transport simulations of solute breakthrough at the outlet of a sand-like porous medium evidence marked deviations from the hydrodynamic dispersion paradigm and identify two distinct regimes. The first regime is characterised by a broad distribution of advective residence times in single pores. The second regime is characterised by diffusive mass transfer into low-velocity regions in the wake of solid grains. These mechanisms are quantified systematically in the framework of a time-domain random walk for the motion of marked elements (particles) of the transported material quantity. Particle transitions occur over the length scale imprinted in the pore structure at random times given by heterogeneous advection and diffusion. Under globally advection-dominated conditions, i.e., Péclet numbers larger than 1, particles sample the intrapore velocities by diffusion and the interpore velocities through advection. Thus, for a single transition, particle velocities are approximated by the mean pore velocity. In order to quantify this advection mechanism, we develop a model for the statistics of the Eulerian velocity magnitude based on Poiseuille’s law for flow through a single pore and for the distribution of mean pore velocities, both of which are linked to the distribution of pore diameters. Diffusion across streamlines through immobile zones in the wake of solid grains gives rise to exponentially distributed residence times that decay on the diffusion time over the pore length. The trapping rate is determined by the inverse diffusion time. This trapping mechanism is represented by a compound Poisson process conditioned on the advective residence time in the proposed time-domain random walk approach. The model is parameterised with the characteristics of the porous medium under consideration and captures both preasymptotic regimes. Macroscale transport is described by an integro-differential equation for solute concentration, whose memory kernels are given in terms of the distribution of mean pore velocities and trapping times. This approach quantifies the physical non-equilibrium caused by a broad distribution of mass transfer time scales, both advective and diffusive, on the representative elementary volume (REV). Thus, while the REV indicates the scale at which medium properties like porosity can be uniquely defined, this does not imply that transport can be characterised by hydrodynamic dispersion.
Entrapping an impacting particle at a liquid–gas interface
Authors: Chen Han , Liu Hao-Ran , Lu Xi-Yun , Ding Hang
Published: March 2018

We numerically investigate the mechanism leading to the entrapment of spheres at the gas–liquid interface after impact. Upon impact onto a liquid pool, a hydrophobic sphere is seen to follow one of the three regimes identified in the experiment (Lee & Kim, Langmuir, vol. 24, 2008, pp. 142–145): sinking, bouncing or being entrapped at the interface. It is important to understand the role of wettability in this process of flow–structure interaction with dynamic wetting, and in particular, to what extent the wettability can determine whether the sphere is entrapped at the interface. For this purpose, a diffuse-interface immersed boundary method is adopted in the numerical simulations. We expand the parameter space considered previously, provide the phase diagrams and identify the key phenomena in the impact dynamics. Then, we propose the scaling models to interpret the critical conditions for the occurrence of sphere entrapment, accounting for the wettability of the sphere. The models are shown to provide a good correlation among the impact inertia of the drop, the surface tension, the wettability and the density ratio of the sphere to the liquid.
On the dynamics of a thin viscous film spreading between a permeable horizontal plate and an elastic sheet
Authors: Box F. , Neufeld Jerome A. , Woods Andrew W.
Published: March 2018

The two-dimensional dynamics of a thin film of viscous fluid spreading between a permeable horizontal plate and an overlying thin elastic sheet is explored. We use a lubrication model to describe the balance between the elastic stress, the hydrostatic pressure gradient and the viscous resistance of the flow, as fluid spreads laterally from a source and simultaneously drains through the plate. A family of asymptotic solutions are described in which the flow is dominated by either the hydrostatic pressure gradient or the elastic stress associated with the deformation of the sheet. In these solutions, although the deformation of the sheet above the porous plate arises from the fluid flow below the sheet, the fluid typically separates from the sheet a short distance upstream of the full extent of the draining zone, with the region of flow being driven purely by the hydrostatic pressure gradient. As a result, an air gap develops below the sheet up to the point where it touches back down onto the plate. With a very light or stiff elastic sheet, this touchdown point may extend far beyond the fluid draining zone, but otherwise it is similar to the extent of the draining zone.
Annular swirling liquid layer with a hollow core
Authors: Bardet P. M. , Peterson P. F. , Savaş Ö.
Published: March 2018

A thick turbulent annular liquid layer that swirls inside a fixed pipe is studied by means of surface observations and stereoscopic particle image velocimetry in an index-matched nozzle facility. This flow combines the complexities of swirling and free-surface turbulence. The free surface of the layer changes the boundary condition compared to filled swirling pipes and introduces the equivalent of a hollow core. The liquid layer shares similarities with turbulent open-channel flows, with the high centrifugal force across the layer having a similar effect to that of gravity in channel flows. At the surface, the restoring forces are surface tension and centrifugal acceleration. The particular nozzle under study has been envisioned for inertial confinement fusion, but the flow has relevance to systems such as compact separators or liquid rocket fuel injectors. Data are acquired at five downstream locations from the nozzle exit for four Reynolds numbers for subcritical flows. Injection flow rate and fluid kinematic viscosity are controlled independently, which allows adjusting independently the Reynolds and Taylor–Reynolds numbers. This also enables control of the centrifugal force at the free surface to test the effects of turbulence intensity on the free surface in regimes where air entrainment and droplet ejection occur. The swirl number is fixed by the design of the nozzle. From velocimetry data, mean velocity and turbulence statistics are extracted. For all the conditions tested, three flow regimes are identified: developing, developed, and transitional. The developed regime appears self-similar on the mean; the swirl creates a favourable pressure gradient that sustains the axial flow and confines the boundary layer near the wall. Large coherent vortex structures are identified in the layer. A simple model is proposed to describe the layer thickness and the velocity distribution in it. In the transitional regime, helical varicose waves generated by centrifugal instability are observed on the surface. Additionally, wall effects are visible in the bulk of the flow, and the main flow features are large overturning motions.
On the interaction of very-large-scale motions in a neutral atmospheric boundary layer with a row of wind turbines
Authors: Önder Asim , Meyers Johan
Published: March 2018

Recent experiments have revealed the existence of very long streamwise features, denoted as very-large-scale motions (VLSMs), in the thermally neutral atmospheric boundary layer (ABL) (Hutchins et al., Boundary-Layer Meteorol., vol. 145(2), 2012, pp. 273–306). The aim of our study is to elaborate the role of these large-scale anisotropic patterns in wind-energy harvesting with special emphasis on the organization of turbulent fields around wind turbines. To this end, we perform large-eddy simulation (LES) of a turbine row operating under neutral conditions. The ABL data are produced separately in a very long domain of $240\unicode[STIX]{x1D6FF}$, where $\unicode[STIX]{x1D6FF}$ is the ABL thickness, to ensure a realistic representation for very large scales of $O(10\unicode[STIX]{x1D6FF})$. VLSMs are extracted from the LES database using a cutoff at streamwise wavelength $\unicode[STIX]{x1D706}_{x}=5\unicode[STIX]{x1D6FF}$, or $\unicode[STIX]{x1D706}_{x}=50D$ in terms of turbine diameter. Reynolds averaging of low-pass filtered fields shows that the interaction of VLSMs and turbines produce very-long-wavelength motions in the wake region, which contain approximately $20\,\%$ of the resolved Reynolds shear stress, and $30\,\%$ of the resolved streamwise kinetic energy in the shear layers. To further elucidate these statistics, we conduct a geometrical analysis using conditional averaging based on large-scale low- and high-velocity events. The conditional eddies provide evidence for very long (${\sim}10\unicode[STIX]{x1D6FF}$) and wide (${\sim}\unicode[STIX]{x1D6FF}$) streak–roller structures around the turbine row. Although all of these eddies share the same streak–roller topology, there are remarkable modifications in the morphology of the conditional eddies whose cores are located sideways to the turbines. In these cases, the turbine row pushes the whole low- or high-momentum streak aside, and prevails as a sharp boundary to the low–high-momentum streak pair. In this process, accompanying rollers remain relatively unaffected. This creates a two-way flux towards the turbine row. These observations provide some insights about the high lateral spreading observed in the large-scale Reynolds stress fields.
Resilience by structural entrenchment: Dynamics of single-layer and multiplex networks following sudden changes to tie costs
Authors: SMALDINO PAUL E. , D'SOUZA RAISSA M. , MAOZ ZEEV
Published: March 2018

We examine a model of network formation in single-layer and multiplex networks in which individuals have positive incentives for social ties, closed triangles, and spillover edges. In particular, we investigate the influence of shocks to the network in which the cost of social ties changes after an initial equilibrium. We highlight the emergence ofstructural entrenchment: the retention of structural features, such as closed triangles and spillover edges, which are formed under historically different conditions from those currently driving network evolution. This work has broad implications for understanding path dependence in the structure and dynamics of single-layer and multiplex networks.
Remarkable differences in the presence of the acanthocephalan parasite Echinorhynchus truttae in brown trout (Salmo trutta) captured in two adjacent river basins in Galicia (NW Spain)
Authors: Couso-Pérez Seila , Cañizo-Outeiriño Antonio , Campo-Ramos Rainer , Ares-Mazás Elvira , Gómez-Couso Hipólito
Published: March 2018

This is the first report on the presence of acanthocephalan parasiteEchinorhynchus truttaein brown trout (Salmo trutta) from Spain. A total of 343 fish were captured by local anglers from 19 rivers in the adjacent Tambre and Ulla watersheds in Galicia (north-western Spain). Macroscopic and microscopic analyses of the intestinal contents revealed the presence of adults and/or eggs ofE. truttaein 53 of the 123 trout from Tambre river basin (43.1%). By contrast, parasitic forms of this acanthocephalan were only observed in eight of the 220 fish from Ulla basin (3.6%), showing significant differences between the prevalences obtained in two adjacent watersheds (P< 0.001, odds ratio 19.0). Prevalence was significantly higher in specimens >3 years (length >26.0 cm) than in younger specimens (P< 0.05). The absence ofGammarus pulexin the region suggests that native gammarid species in Galicia (Echinogammarus lusitanicusandEchinogammarus beriyoni) may act as intermediate host in the life cycle ofE. truttae. Different prevalences ofE. truttaeindicate that the presence/abundance of the intermediate crustacean host may be different in the two river basins, probably as a consequence of various abiotic factors and anthropogenic activities.
The efficacy of daily snack replacement with oligofructose-enriched granola bars in overweight and obese adults: a 12-week randomised controlled trial
Authors: Pol Korrie , de Graaf Cees , Meyer Diederick , Mars Monica
Published: March 2018

Oligofructose is a prebiotic dietary fibre obtained from chicory root inulin. Oligofructose supplementation may affect satiety, food intake, body weight and/or body composition. The aim was to examine the efficacy of oligofructose-supplemented granola bars on the following weight management outcomes: satiety, energy intake, body weight and body composition in overweight or obese adults. In all, fifty-five adults with overweight or obesity (thirty-six females/nineteen males; age: 41 (sd12) years; 90·6 (sd11·8) kg; BMI: 29·4 (sd2·6) kg/m2) participated in a parallel, triple-blind, placebo-controlled intervention. A total of twenty-nine subjects replaced their snacks twice a day with an equienergetic granola bar supplemented with 8 g of oligofructose (OF-Bar). Subjects in the control group (n26) replaced their snack with a control granola bar without added oligofructose (Co-Bar). Satiety, 24-h energy intake, body weight and body composition (fat mass and waist circumference) were measured at baseline, weeks 6 and 12. In addition, weekly appetite and gastrointestinal side effects were measured. During the intervention, energy intake, body weight and fat mass remained similar in the Co-Bar and OF-Bar groups (allP>0·05). Both groups lost 0·3 (sd1·2) kg lean mass (P<0·01) and reduced their waist circumference with −2·2 (sd3·6) cm (P<0·0001) after 12 weeks. The OF-Bar group reported decreased hunger in later weeks of the intervention (P=0·04), less prospective food consumption (P=0·03) and less thirst (P=0·003). To conclude, replacing daily snacks for 12 weeks with oligofructose-supplemented granola bars does not differentially affect energy intake, body weight and body composition compared with a control bar. However, there was an indication that appetite was lower after oligofructose bar consumption.
Disparities in the management of cardiovascular risk factors in patients with psychiatric disorders: a systematic review and meta-analysis
Authors: Ayerbe Luis , Forgnone Ivo , Foguet-Boreu Quintí , González Esteban , Addo Juliet , Ayis Salma
Published: March 2018

Background

The high cardiovascular (CV) morbidity and mortality reported for patients with psychiatric disorders may possibly be due to a poorer management of CV risk factors (CVRFs). However, these healthcare disparities remain poorly understood. In this paper, studies comparing the management of smoking, diabetes, hypertension and dyslipidaemia, in patients with and without depression, anxiety, schizophrenia, bipolar or personality disorder, were reviewed.

Methods

Prospective studies comparing rates of screening, diagnosis, treatment and control of CVRFs were searched in PubMed, Embase, PsychInfo, Scopus and Web of Science (inception to January 2017). The Meta-analysis of Observational Studies in Epidemiology (MOOSE) criteria were used. Studies were assessed for quality. Wherever possible, meta-analyses were conducted to summarize the findings.

Results

Twenty studies, out of the 18 333 references initially identified, were included. Most studies were heterogeneous in design. Two areas permitted meta-analyses: the pooled odds ratio for quitting smoking for those with depression was 0.64 (0.49–0.80) p < 0.001; the pooled difference of glycated haemoglobin for patients with type 2 diabetes and depression was 0.18 (0.06–0.31) p = 0.005. Individual studies showed associations between: schizophrenia and lower probability of having smoking habit recorded; schizoid personality disorder and higher probability of remaining non-smokers after quitting; anxiety and poorer control of type I diabetes; depression, anxiety or schizophrenia and lower probability of having a diagnosis of hypertension; schizophrenia or bipolar disorder and lower use of antihypertensive and lipid-lowering drugs.

Conclusions

A proactive clinical management, together with further studies, are needed to reduce the CV morbidity and mortality of patients with psychiatric disorders.
Associations of anabolic-androgenic steroid use with other behavioral disorders: an analysis using directed acyclic graphs
Authors: Kanayama Gen , Pope Harrison G. , Hudson James I.
Published: March 2018

Background

Anabolic-androgenic steroid (AAS) use is known to be associated with other psychiatric disorders, such as body image disorders, conduct disorder/sociopathy, and other substance use disorders (SUD) – but the causal pathways among these conditions remain poorly delineated.

Methods

We created a directed acyclic graph to diagram hypothesized relationships among AAS use and dependence, body image disorder (BID), conduct disorder/sociopathy, and other SUD. Using proportional hazards models, we then assessed potentially causal relationships among these variables, using a dataset of 233 male weightlifters, of whom 102 had used AAS.

Results

BID and conduct disorder/sociopathy both strongly contributed to the development of AAS use, but did not appear to contribute further to the progression from AAS use to AAS dependence. Other SUD beginning prior to first AAS use – whether broadly defined or restricted only to opioids – failed to show an effect on AAS use or progression to AAS dependence. Conversely, AAS use contributed significantly to the subsequent first-time development of opioid use disorders but did not significantly increase the risk for first-time development of non-opioid SUD, taken as a whole.

Conclusions

Our analysis suggests that AAS use and other SUD are mutually attributable to underlying conduct disorder/sociopathy. SUD do not appear to represent a ‘gateway’ to subsequent AAS use. AAS use may represent a gateway to subsequent opioid use disorder, but probably not to other SUD.
Parsing profiles of temperamental reactivity and differential routes to delay of gratification: A person-based approach
Authors: Suor Jennifer H. , Sturge-Apple Melissa L. , Jones-Gordils Hannah R.
Published: March 2018

Informed by a developmental psychopathology perspective, the present study applied a person-based approach to examine whether associations between early sociocontextual experiences (e.g., socioeconomic factors and maternal discipline practices) and preschool-age children's delay of gratification vary across profiles of children's temperamental reactivity. In addition, the study examined the direct and mediating role of children's set shifting in associations with delay of gratification within each profile. The sample consisted of 160 socioeconomically and ethnically diverse mothers and their 5-year-old children drawn from a longitudinal study of mother–child relationships. Latent profile analyses identified three profiles of temperamental reactivity distinguished by sensitivity to reward and punishment and negative affectivity. Multigroup analysis revealed maternal sensitive discipline (observed during a parent–child compliance task) at age 3.5 predicted longer delay of gratification at age 5 in the punishment reactivity/negative affectivity group. Maternal inductive reasoning discipline at age 3.5 predicted longer delay in the low temperamental reactivity group. For children with the reward reactivity/negative affectivity profile, higher family income at age 3.5 predicted longer delay of gratification at age 5, which was mediated by children's set shifting. Findings underscore the utility of person-based approaches for delineating differential developmental routes toward children's delay of gratification.
Beyond Helpless Victims and Survivor Trauma: New Historiography on Jews in the Age of the Holocaust
Authors: LACZÓ FERENC
Published: March 2018

This review essay explores recent scholarship on the history of Jews in the post-Habsburg territories, before and after the Second World War. The impressive wave of scholarship that has emerged in recent decades on European Jewish history shortly before, during and, increasingly, after the Holocaust, has only made historians more aware of how much they have left to do to reconstruct, at least in text, the lives of European Jews – a multilingual and culturally, economically and politically heterogeneous group – that the Holocaust so systematically and brutally destroyed. Aiming to overcome reductionist attempts that either subsume the history of Jews under a national narrative or parcel it into separate national units without comparative or transnational agendas, a growing number of scholars aim to reconceptualise Jewish history as being crucial to European and global history.
Adolescent perspectives of the recreational ice hockey food environment and influences on eating behaviour revealed through photovoice
Authors: Caswell M Susan , Hanning Rhona M
Published: March 2018

Objective

Unhealthy dietary behaviours are prevalent among adolescents. This might relate, in part, to obesogenic environments, including recreation food facilities. The REFRESH Study (Recreation Environment and Food Research: Experiences from Hockey) aimed to explore, from the perspectives of adolescent ice hockey players and parents, broad social and physical environmental influences on adolescent food behaviours associated with hockey participation.

Design

Players used photovoice to describe their food experiences in relation to ice hockey. The approach included photos, individual interviews and focus groups. Exemplar photographs were exhibited for stakeholders, including five parents who were interviewed. Interview and focus group transcripts were thematically analysed.

Setting

Recreational ice hockey environment, Ontario, Canada, 2015–16.

Subjects

Ice hockey players (n24) aged 11–15 years recruited from five leagues.

Results

Dominant influences among players included: their perceived importance of nutrients (e.g. protein) or foods (e.g. chocolate milk) for performance and recovery; marketing and branding (e.g. the pro-hockey aura of Tim Horton’s®, Canada’s largest quick-service restaurant); social aspects of tournaments and team meals; and moral values around ‘right’ and ‘wrong’ food choices. Both players and parents perceived recreational facility food options as unhealthy and identified that travel and time constraints contributed to less healthy choices.

Conclusions

Results indicate recreation facilities are only one of a range of environments that influence eating behaviours of adolescent ice hockey players. Players’ susceptibility to advertising/brand promotion and the value of healthy food choices for performance are findings that can inform policy and interventions to support healthy environments and behaviours.
The Diffusion of Protestantism in Northern Europe: Historical Embeddedness and Complex Contagions in the Adoption of the Reformation
Authors: Wurpts Bernd , Corcoran Katie E. , Pfaff Steven
Published: March 2018

In this article we use network theory to explain the adoption of the Protestant Reformation. We use new historical data on the connections between Hansa towns that allow us to conduct the first social network study of the Protestant Reformation. Based on an analysis of cities in central and Western Europe between 1517 and 1530, we find evidence for diffusion through both simple and complex contagion. Our operationalization of network data based on medieval Hansa Diets points to the complex association between tie weights (i.e., the strength of ties) and numbers of ties in network diffusion. Using optimal tuning parameters for simple adoption models, we show that a combination of strong ties and weak ties fostered Protestant adoption in northern cities.
The Government Sidelines Science, but to What Extent?
Authors: Goldman Gretchen , Carter Jacob , Johnson Charise
Published: March 2018

Anecdotes paint a grim picture about the state of scientific integrity in the current administration. Results from a newly opened and broad survey will show us this problem's full scope.
Soil pH mediates the balance between stochastic and deterministic assembly of bacteria
Authors: Tripathi Binu M , Stegen James C , Kim Mincheol , Dong Ke , Adams Jonathan M , Lee Yoo Kyung
Published: March 2018

Little is known about the factors affecting the relative influences of stochastic and deterministic processes that govern the assembly of microbial communities in successional soils. Here, we conducted a meta-analysis of bacterial communities using six different successional soil datasets distributed across different regions. Different relationships between pH and successional age across these datasets allowed us to separate the influences of successional age (i.e., time) from soil pH. We found that extreme acidic or alkaline pH conditions lead to assembly of phylogenetically more clustered bacterial communities through deterministic processes, whereas pH conditions close to neutral lead to phylogenetically less clustered bacterial communities with more stochasticity. We suggest that the influence of pH, rather than successional age, is the main driving force in producing trends in phylogenetic assembly of bacteria, and that pH also influences the relative balance of stochastic and deterministic processes along successional soils. Given that pH had a much stronger association with community assembly than did successional age, we evaluated whether the inferred influence of pH was maintained when studying globally distributed samples collected without regard for successional age. This dataset confirmed the strong influence of pH, suggesting that the influence of soil pH on community assembly processes occurs globally. Extreme pH conditions likely exert more stringent limits on survival and fitness, imposing strong selective pressures through ecological and evolutionary time. Taken together, these findings suggest that the degree to which stochastic vs. deterministic processes shape soil bacterial community assembly is a consequence of soil pH rather than successional age.
Ischemic preconditioning attenuates ischemia/reperfusion-induced kidney injury by activating autophagy via the SGK1 signaling pathway
Authors: Xie Ying , Jiang Daofang , Xiao Jing , Fu Chensheng , Zhang Zhenxing , Ye Zhibin , Zhang Xiaoli
Published: March 2018

Ischemic preconditioning (IPC) has a strong renoprotective effect during renal ischemia/reperfusion (I/R) injury that is thought to relate to autophagy. However, the role of autophagy during IPC-afforded renoprotection and the precise mechanisms involved are unknown. In this study, an in vitro hypoxia/reoxygenation (H/R) model was established in which oxygen and glucose deprivation (OGD) was applied to renal cells for 15 h followed by reoxygenation under normal conditions for 30 min, 2 h or 6 h; transient OGD and subsequent reoxygenation were implemented before prolonged H/R injury to achieve hypoxic preconditioning (HPC). 3-Methyladenine (3-MA) was used to inhibit autophagy. In a renal I/R injury model, rats were subjected to 40 min of renal ischemia followed by 6 h, 12 h or 24 h of reperfusion. IPC was produced by four cycles of ischemia (8 min each) followed by 5 min of reperfusion prior to sustained ischemia. We found that IPC increased LC3II and Beclin-1 levels and decreased SQSTM/p62 and cleaved caspase-3 levels in a time-dependent manner during renal I/R injury, as well as increased the number of intracellular double-membrane vesicles in injured renal cells. IPC-induced renal protection was efficiently attenuated by pretreatment with 5 mM 3-MA. Pretreatment with IPC also dynamically affected the expression of SGK1/FOXO3a/HIF-1α signaling components. Moreover, knocking down SGK1 expression significantly downregulated phosphorylated-FOXO3a (p-FOXO3a)/FOXO3 and HIF-1α, suppressed LC3II and Beclin-1 levels, increased SQSTM/p62 and cleaved caspase-3 levels, and abolished the protective effect of IPC against I/R-induced renal damage. SGK1 overexpression efficiently increased p-FOXO3a/FOXO3 and HIF-1α levels, promoted the autophagy flux and enhanced the protective effect mediated by HPC. Furthermore, FOXO3a overexpression decreased HIF-1α protein levels, inhibited HIF-1α transcriptional activity and reduced the protective effect of IPC. Our study indicates that IPC can ameliorate renal I/R injury by promoting autophagy through the SGK1 pathway.
Sei-1 promotes double minute chromosomes formation through activation of the PI3K/Akt/BRCA1-Abraxas pathway and induces double-strand breaks in NIH-3T3 fibroblasts
Authors: Tian Xing , Liu Chang , Wang Xin , Wang Fei , Wang Liqun , Xu Lu , Ma Jinfa , Gao Yating , Bao Yantao , Wang Falin , Sun Luyao , Wei Junni , Lin Chuwen , Zhang He , Zhu Gang , Guan Xinyuan , Fu Songbin , Zhang Chunyu
Published: March 2018

Sei-1 is a potential oncogene that plays an important role in promoting genomic instability. Double minute chromosomes (DMs) are hallmarks of gene amplification and contribute to tumorigenesis. Defects in the DNA double-strand break (DSB) repairing pathways can lead to gene amplification. To date, the mechanisms governing the formation of DMs induced by Sei-1 are not fully understood. We established DMs induced by Sei-1 in the NIH-3T3 cell line. RNA-sequencing was used to identify key characteristics of differentially expressed genes. Metaphase spreads were used to calculate DM numbers. Immunofluorescence was employed to detect γH2AX foci. Western blot and Akt pathway inhibition experiments were performed to reveal the role of the PI3K/Akt/BRCA1-Abraxas pathway in Sei-1-induced DMs. Luciferase reporter assay was employed to explore the regulatory mechanisms between Sei-1 and BRCA1. DM formation was associated with a deficiency in DSB repair. Based on this finding, activation of the PI3K/Akt/BRCA1-Abraxas pathway was found to increase the DM population with passage in vivo, and inhibition resulted in a reduction of DMs. Apart from this, it was shown for the first time that Sei-1 could directly regulate the expression of BRCA1. Our results suggest that the PI3K/Akt/BRCA1-Abraxas pathway is responsible for the formation of DMs induced by Sei-1.
Dioscin inhibits stem-cell-like properties and tumor growth of osteosarcoma through Akt/GSK3/β-catenin signaling pathway
Authors: Liu Weihai , Zhao Zhiqiang , Wang Yongqian , Li Wuguo , Su Qiao , Jia Qiang , Zhang Jiajun , Zhang Xuelin , Shen Jingnan , Yin Junqiang
Published: March 2018

Osteosarcoma is the most common primary bone tumor in children and adolescents. Many patients with osteosarcoma always develop drug resistance to current chemotherapy regimens, which induces a poor prognosis. And cancer stem cells (CSCs) have been reported to possess the properties to self-renew and maintain the phenotype of tumor, which may lead to clinical treatment failure. Thus, it is an urgent task to develop several potentially useful therapeutic agents, which could target CSCs in osteosarcoma. This study aims to clarify the in vitro and in vivo anti-osteosarcoma effects of dioscin, the primary component derived from Discorea nipponica Makino, and its molecular mechanism of action. In this study, all the ten human osteosarcoma cell lines were sensitive to dioscin treatment in a dose- and time-dependent manner. Dioscin inhibits proliferation and induces cell cycle arrest as well as apoptotic cell death in osteosarcoma cells. More importantly, oral administration of dioscin (60 mg/kg) showed significant therapeutic effect on osteosarcoma growth without obvious side effects in vivo. In addition, dioscin possesses the ability to suppress stem-cell-like phenotype of osteosarcoma cells. Mechanistically, dioscin inhibits osteosarcoma stem-cell-like properties and tumor growth through repression of Akt/GSK3/β-catenin pathway. Moreover, β-catenin expression in osteosarcoma patients was associated with clinical prognosis. Conclusively, the present study provides comprehensive evidence for the inhibition of dioscin on osteosarcoma stem-cell-like properties and tumor growth through repression of Akt/GSK3/β-catenin pathway, which suggests dioscin as a promising therapeutic regimen. And β-catenin may be a potential therapeutic target as well as a significant prognostic marker for osteosarcoma patients in clinic.
MTSS1 and SCAMP1 cooperate to prevent invasion in breast cancer
Authors: Vadakekolathu Jayakumar , Al-Juboori Shaymaa Ismael Kadhim , Johnson Catherine , Schneider Anne , Buczek Magdalena Elżbieta , Di Biase Anna , Pockley Alan Graham , Ball Graham Roy , Powe Desmond George , Regad Tarik
Published: March 2018

Cell–cell adhesions constitute the structural “glue” that retains cells together and contributes to tissue organisation and physiological function. The integrity of these structures is regulated by extracellular and intracellular signals and pathways that act on the functional units of cell adhesion such as the cell adhesion molecules/adhesion receptors, the extracellular matrix (ECM) proteins and the cytoplasmic plaque/peripheral membrane proteins. In advanced cancer, these regulatory pathways are dysregulated and lead to cell–cell adhesion disassembly, increased invasion and metastasis. The Metastasis suppressor protein 1 (MTSS1) plays a key role in the maintenance of cell–cell adhesions and its loss correlates with tumour progression in a variety of cancers. However, the mechanisms that regulate its function are not well-known. Using a system biology approach, we unravelled potential interacting partners of MTSS1. We found that the secretory carrier-associated membrane protein 1 (SCAMP1), a molecule involved in post-Golgi recycling pathways and in endosome cell membrane recycling, enhances Mtss1 anti-invasive function in HER2+/ER−/PR− breast cancer, by promoting its protein trafficking leading to elevated levels of RAC1-GTP and increased cell–cell adhesions. This was clinically tested in HER2 breast cancer tissue and shown that loss of MTSS1 and SCAMP1 correlates with reduced disease-specific survival. In summary, we provide evidence of the cooperative roles of MTSS1 and SCAMP1 in preventing HER2+/ER−/PR− breast cancer invasion and we show that the loss of Mtss1 and Scamp1 results in a more aggressive cancer cell phenotype.
The distinct roles of mesenchymal stem cells in the initial and progressive stage of hepatocarcinoma
Authors: Zong Chen , Zhang Hangjie , Yang Xue , Gao Lu , Hou Jing , Ye Fei , Jiang Jinghua , Yang Yang , Li Rong , Han Zhipeng , Wei Lixin
Published: March 2018

Increasing evidences suggest that mesenchymal stem cells (MSCs) could migrate to the tumor site and play a vital role in tumorigenesis and progression. However, it is still a lively debate whether MSCs exert a pro- or anticancer action. Cancer development and progression is a multistep process. Therefore, we investigated the effect of MSCs on hepatocarcinoma and whether the role of MSCs depends on the stage of cancer development. In our study, chronically exposing rats to N-diethylnitrosamine (DEN) was employed as hepatocarcinoma model. And to evaluate the effect of MSCs on hepatocarcinoma, the animals were divided into three groups: rats were injected with MSCs in the initial (DEN + MSC (Is) group) or progressive stage (DEN + MSC (Ps) group) of hepatocarcinoma, respectively. Rats injected with PBS were used as control (DEN group). Interestingly, we found that MSCs had a tumor-suppressive effect in the Is of hepatocarcinoma, yet a tumor-promotive effect in the Ps. In the Is, MSCs showed a protective role against drug damage, possibly through reducing DNA damage and ROS accumulation. Meanwhile, MSCs in the Is also exhibited anti-inflammatory and anti-liver fibrosis effect. Further, in the Ps, MSCs facilitated tumor formation not only by enhancing cancer cell proliferation but also through promoting stem cell-like properties and epithelial–mesenchymal transition of liver cancer cells. Taken together, MSCs have a paradoxical role in the different stages of hepatocarcinogenesis, which sheds new light on the role of MSCs in hepatocarcinoma and cautions the therapeutic application of MSCs for liver cancer.
Two-electron spin correlations in precision placed donors in silicon
Authors: Broome M. A. , Gorman S. K. , House M. G. , Hile S. J. , Keizer J. G. , Keith D. , Hill C. D. , Watson T. F. , Baker W. J. , Hollenberg L. C. L. , Simmons M. Y.
Published: March 2018

Substitutional donor atoms in silicon are promising qubits for quantum computation with extremely long relaxation and dephasing times demonstrated. One of the critical challenges of scaling these systems is determining inter-donor distances to achieve controllable wavefunction overlap while at the same time performing high fidelity spin readout on each qubit. Here we achieve such a device by means of scanning tunnelling microscopy lithography. We measure anti-correlated spin states between two donor-based spin qubits in silicon separated by 16 ± 1 nm. By utilising an asymmetric system with two phosphorus donors at one qubit site and one on the other (2P−1P), we demonstrate that the exchange interaction can be turned on and off via electrical control of two in-plane phosphorus doped detuning gates. We determine the tunnel coupling between the 2P−1P system to be 200 MHz and provide a roadmap for the observation of two-electron coherent exchange oscillations.
Genome-wide analysis yields new loci associating with aortic valve stenosis
Authors: Helgadottir Anna , Thorleifsson Gudmar , Gretarsdottir Solveig , Stefansson Olafur A. , Tragante Vinicius , Thorolfsdottir Rosa B. , Jonsdottir Ingileif , Bjornsson Thorsteinn , Steinthorsdottir Valgerdur , Verweij Niek , Nielsen Jonas B. , Zhou Wei , Folkersen Lasse , Martinsson Andreas , Heydarpour Mahyar , Prakash Siddharth , Oskarsson Gylfi , Gudbjartsson Tomas , Geirsson Arnar , Olafsson Isleifur , Sigurdsson Emil L. , Almgren Peter , Melander Olle , Franco-Cereceda Anders , Hamsten Anders , Fritsche Lars , Lin Maoxuan , Yang Bo , Hornsby Whitney , Guo Dongchuan , Brummett Chad M. , Abecasis Gonçalo , Mathis Michael , Milewicz Dianna , Body Simon C. , Eriksson Per , Willer Cristen J. , Hveem Kristian , Newton-Cheh Christopher , Smith J. Gustav , Danielsen Ragnar , Thorgeirsson Gudmundur , Thorsteinsdottir Unnur , Gudbjartsson Daniel F. , Holm Hilma , Stefansson Kari
Published: March 2018

Aortic valve stenosis (AS) is the most common valvular heart disease, and valve replacement is the only definitive treatment. Here we report a large genome-wide association (GWA) study of 2,457 Icelandic AS cases and 349,342 controls with a follow-up in up to 4,850 cases and 451,731 controls of European ancestry. We identify two new AS loci, on chromosome 1p21 near PALMD (rs7543130; odds ratio (OR) = 1.20, P = 1.2 × 10−22) and on chromosome 2q22 in TEX41 (rs1830321; OR = 1.15, P = 1.8 × 10−13). Rs7543130 also associates with bicuspid aortic valve (BAV) (OR = 1.28, P = 6.6 × 10−10) and aortic root diameter (P = 1.30 × 10−8), and rs1830321 associates with BAV (OR = 1.12, P = 5.3 × 10−3) and coronary artery disease (OR = 1.05, P = 9.3 × 10−5). The results implicate both cardiac developmental abnormalities and atherosclerosis-like processes in the pathogenesis of AS. We show that several pathways are shared by CAD and AS. Causal analysis suggests that the shared risk factors of Lp(a) and non-high-density lipoprotein cholesterol contribute substantially to the frequent co-occurence of these diseases.
Ultra-thin enzymatic liquid membrane for CO2 separation and capture
Authors: Fu Yaqin , Jiang Ying-Bing , Dunphy Darren , Xiong Haifeng , Coker Eric , Chou Stanley S. , Zhang Hongxia , Vanegas Juan M. , Croissant Jonas G. , Cecchi Joseph L. , Rempe Susan B. , Brinker C. Jeffrey
Published: March 2018

The limited flux and selectivities of current carbon dioxide membranes and the high costs associated with conventional absorption-based CO2 sequestration call for alternative CO2 separation approaches. Here we describe an enzymatically active, ultra-thin, biomimetic membrane enabling CO2 capture and separation under ambient pressure and temperature conditions. The membrane comprises a ~18-nm-thick close-packed array of 8 nm diameter hydrophilic pores that stabilize water by capillary condensation and precisely accommodate the metalloenzyme carbonic anhydrase (CA). CA catalyzes the rapid interconversion of CO2 and water into carbonic acid. By minimizing diffusional constraints, stabilizing and concentrating CA within the nanopore array to a concentration 10× greater than achievable in solution, our enzymatic liquid membrane separates CO2 at room temperature and atmospheric pressure at a rate of 2600 GPU with CO2/N2 and CO2/H2 selectivities as high as 788 and 1500, respectively, the highest combined flux and selectivity yet reported for ambient condition operation.
Ice-volume-forced erosion of the Chinese Loess Plateau global Quaternary stratotype site
Authors: Stevens T. , Buylaert J.-P. , Thiel C. , Újvári G. , Yi S. , Murray A. S. , Frechen M. , Lu H.
Published: March 2018

The International Commission on Stratigraphy (ICS) utilises benchmark chronostratigraphies to divide geologic time. The reliability of these records is fundamental to understand past global change. Here we use the most detailed luminescence dating age model yet published to show that the ICS chronology for the Quaternary terrestrial type section at Jingbian, desert marginal Chinese Loess Plateau, is inaccurate. There are large hiatuses and depositional changes expressed across a dynamic gully landform at the site, which demonstrates rapid environmental shifts at the East Asian desert margin. We propose a new independent age model and reconstruct monsoon climate and desert expansion/contraction for the last ~250 ka. Our record demonstrates the dominant influence of ice volume on desert expansion, dust dynamics and sediment preservation, and further shows that East Asian Summer Monsoon (EASM) variation closely matches that of ice volume, but lags insolation by ~5 ka. These observations show that the EASM at the monsoon margin does not respond directly to precessional forcing.
A conserved interaction of the dynein light intermediate chain with dynein-dynactin effectors necessary for processivity
Authors: Lee In-Gyun , Olenick Mara A. , Boczkowska Malgorzata , Franzini-Armstrong Clara , Holzbaur Erika L. F. , Dominguez Roberto
Published: March 2018

Cytoplasmic dynein is the major minus-end-directed microtubule-based motor in cells. Dynein processivity and cargo selectivity depend on cargo-specific effectors that, while generally unrelated, share the ability to interact with dynein and dynactin to form processive dynein–dynactin-effector complexes. How this is achieved is poorly understood. Here, we identify a conserved region of the dynein Light Intermediate Chain 1 (LIC1) that mediates interactions with unrelated dynein–dynactin effectors. Quantitative binding studies map these interactions to a conserved helix within LIC1 and to N-terminal fragments of Hook1, Hook3, BICD2, and Spindly. A structure of the LIC1 helix bound to the N-terminal Hook domain reveals a conformational change that creates a hydrophobic cleft for binding of the LIC1 helix. The LIC1 helix competitively inhibits processive dynein–dynactin-effector motility in vitro, whereas structure-inspired mutations in this helix impair lysosomal positioning in cells. The results reveal a conserved mechanism of effector interaction with dynein–dynactin necessary for processive motility.