bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population fluctuations and spatial synchrony in an arboreal rodent
Authors: Selonen Vesa , Remm Jaanus , Hanski Ilpo K. , Henttonen Heikki , Huitu Otso , Jokinen Maarit , Korpimäki Erkki , Mäkelä Antero , Sulkava Risto , Wistbacka Ralf 
Published: October 2019

Abstract
Climatic conditions, trophic links between species and dispersal may induce spatial synchrony in population fluctuations. Spatial synchrony increases the extinction risk of populations and, thus, it is important to understand how synchrony-inducing mechanisms affect populations already threatened by habitat loss and climate change. For many species, it is unclear how population fluctuations vary over time and space, and what factors potentially drive this variation. In this study, we focus on factors determining population fluctuations and spatial synchrony in the Siberian flying squirrel, Pteromys volans, using long-term monitoring data from 16 Finnish populations located 2–400 km apart. We found an indication of synchronous population dynamics on a large scale in flying squirrels. However, the synchrony was not found to be clearly related to distance between study sites because the populations seemed to be strongly affected by small-scale local factors. The regularity of population fluctuations varied over time. The fluctuations were linked to changes in winter precipitation, which has previously been linked to the reproductive success of flying squirrels. Food abundance (tree mast) and predator abundance were not related to population fluctuations in this study. We conclude that spatial synchrony was not unequivocally related to distance in flying squirrels, as has been observed in earlier studies for more abundant rodent species. Our study also emphasises the role of climate in population fluctuations and the synchrony of the species.
A Proper Generalized Decomposition (PGD) approach to crack propagation in brittle materials: with application to random field material properties
Authors: Garikapati Hasini , Zlotnik Sergio , Díez Pedro , Verhoosel Clemens V. , van Brummelen E. Harald 
Published: October 2019

Abstract
Understanding the failure of brittle heterogeneous materials is essential in many applications. Heterogeneities in material properties are frequently modeled through random fields, which typically induces the need to solve finite element problems for a large number of realizations. In this context, we make use of reduced order modeling to solve these problems at an affordable computational cost. This paper proposes a reduced order modeling framework to predict crack propagation in brittle materials with random heterogeneities. The framework is based on a combination of the Proper Generalized Decomposition (PGD) method with Griffith’s global energy criterion. The PGD framework provides an explicit parametric solution for the physical response of the system. We illustrate that a non-intrusive sampling-based technique can be applied as a post-processing operation on the explicit solution provided by PGD. We first validate the framework using a global energy approach on a deterministic two-dimensional linear elastic fracture mechanics benchmark. Subsequently, we apply the reduced order modeling approach to a stochastic fracture propagation problem.
Bartter and Gitelman syndromes: Questions of class
Authors: Besouw Martine T. P. , Kleta Robert , Bockenhauer Detlef 
Published: October 2019

AbstractBartter and Gitelman syndromes are rare inherited tubulopathies characterized by hypokalaemic, hypochloraemic metabolic alkalosis. They are caused by mutations in at least 7 genes involved in the reabsorption of sodium in the thick ascending limb (TAL) of the loop of Henle and/or the distal convoluted tubule (DCT). Different subtypes can be distinguished and various classifications have been proposed based on clinical symptoms and/or the underlying genetic cause. Yet, the clinical phenotype can show remarkable variability, leading to potential divergences between classifications. These problems mostly relate to uncertainties over the role of the basolateral chloride exit channel CLCNKB, expressed in both TAL and DCT and to what degree the closely related paralogue CLCNKA can compensate for the loss of CLCNKB function. Here, we review what is known about the physiology of the transport proteins involved in these disorders. We also review the various proposed classifications and explain why a gene-based classification constitutes a pragmatic solution.
Material selection for optimum design of MEMS pressure sensors
Authors: Mehmood Zahid , Haneef Ibraheem , Udrea Florin 
Published: October 2019

AbstractChoice of the most suitable material out of the universe of engineering materials available to the designers is a complex task. It often requires a compromise, involving conflicts between different design objectives. Materials selection for optimum design of a Micro-Electro-Mechanical-Systems (MEMS) pressure sensor is one such case. For optimum performance, simultaneous maximization of deflection of a MEMS pressure sensor diaphragm and maximization of its resonance frequency are two key but totally conflicting requirements. Another limitation in material selection of MEMS/Microsystems is the lack of availability of data containing accurate micro-scale properties of MEMS materials. This paper therefore, presents a material selection case study addressing these two challenges in optimum design of MEMS pressure sensors, individually as well as simultaneously, using Ashby’s method. First, data pertaining to micro-scale properties of MEMS materials has been consolidated and then the Performance and Material Indices that address the MEMS pressure sensor’s conflicting design requirements are formulated. Subsequently, by using the micro-scale materials properties data, candidate materials for optimum performance of MEMS pressure sensors have been determined. Manufacturability of pressure sensor diaphragm using the candidate materials, pointed out by this study, has been discussed with reference to the reported devices. Supported by the previous literature, our analysis re-emphasizes that silicon with 110 crystal orientation [Si (110)], which has been extensively used in a number of micro-scale devices and applications, is also a promising material for MEMS pressure sensor diaphragm. This paper hence identifies an unexplored opportunity to use Si (110) diaphragm to improve the performance of diaphragm based MEMS pressure sensors.
Neural cell responses to wear debris from metal-on-metal total disc replacements
Authors: Lee H. , Phillips J. B. , Hall R. M. , Tipper Joanne L. 
Published: October 2019

Purpose

Abstract
Total disc replacements, comprising all-metal articulations, are compromised by wear and particle production. Metallic wear debris and ions trigger a range of biological responses including inflammation, genotoxicity, cytotoxicity, hypersensitivity and pseudotumour formation, therefore we hypothesise that, due to proximity to the spinal cord, glial cells may be adversely affected.

Methods
Clinically relevant cobalt chrome (CoCr) and stainless steel (SS) wear particles were generated using a six-station pin-on-plate wear simulator. The effects of metallic particles (0.5–50 μm3 debris per cell) and metal ions on glial cell viability, cellular activity (glial fibrillary acidic protein (GFAP) expression) and DNA integrity were investigated in 2D and 3D culture using live/dead, immunocytochemistry and a comet assay, respectively.

Results
CoCr wear particles and ions caused significant reductions in glial cell viability in both 2D and 3D culture systems. Stainless steel particles did not affect glial cell viability or astrocyte activation. In contrast, ions released from SS caused significant reductions in glial cell viability, an effect that was especially noticeable when astrocytes were cultured in isolation without microglia. DNA damage was observed in both cell types and with both biomaterials tested. CoCr wear particles had a dose-dependent effect on astrocyte activation, measured through expression of GFAP.

Conclusions
The results from this study suggest that microglia influence the effects that metal particles have on astrocytes, that SS ions and particles play a role in the adverse effects observed and that SS is a less toxic biomaterial than CoCr alloy for use in spinal devices.

Graphic abstract
These slides can be retrieved under Electronic Supplementary Material.
Revision after failed discectomy
Authors: Mehren Christoph , Wanke-Jellinek Lorenz , Korge Andreas 
Published: October 2019

Abstract

Purpose
Recurrent lumbar disc herniation is the most common complication after discectomy. Due to the altered anatomy with the presence of scar tissue, the surgical revision of already operated patients could be a surgical challenge.

Methods
We describe the microsurgical revision technique step by step with the evaluation of our own clinical results in comparison with primary lumbar disc surgeries. The clinical data are based on a clinical register with 2576 recorded primary surgeries (PD) and 592 cases of revisions (RD) with 12- and 24-month follow-up (FU). The intraoperative dura lesion rates of the surgeries between 2016 and 2018 were recorded retrospectively. Data from 894 primary disc surgeries and 117 revisions were evaluated.

Results
The ODI and the VAS for leg and back pain improved in both groups significantly with slightly inferior outcome of the revision group. The ODI improved from 46.3 (PD) and 45.9 (RD), respectively, to 12.6 (PD) and 22.9 (RD) at the 24-month FU. The VAS dropped down as well in both group [VAS back: 47.8 (PD) and 43.9 (RD) to 19.9 and 32.2 at the 24-month FU; VAS leg: 62.9 (PD) and 65.5 (RD) to 15.6 and 26.8 at the 24-month FU]. During the primary interventions, we observed 1.5% (11/894) and during revisions 7.7% (9/117) of dura lesions.

Conclusions
There is no clear guideline for the surgical treatment of recurrent disc herniations. In most cases, a pure re-discectomy is sufficient and can be performed safely and effectively with the help of a microscope.

Graphic abstract
These slides can be retrieved under Electronic Supplementary Material.
Inception of subsequent stepped leaders in negative cloud-to-ground lightning
Authors: Stolzenburg Maribeth , Marshall Thomas C. , Karunarathne Sumedhe 
Published: October 2019

AbstractTime-correlated high-speed video and electric field change data for 139 natural, negative cloud-to-ground (CG)-lightning flashes reveal 615 return strokes (RSs) and 29 upward-illumination (UI)-type strokes. Among 121 multi-stroke flashes, 56% visibly connected to more than one ground location for either a RS or UI-type stroke. The number of separate ground-stroke connection locations per CG flash averaged 1.74, with maximum 6. This study examines the 88 subsequent strokes that involved a subsequent stepped leader (SSL), either reaching ground or intercepting a former leader to ground, in 61 flashes. Two basic modes by which these SSLs begin are described and are termeddart-then-stepped leadersherein. One inception mode occurs when a dart leader deflects from the prior main channel and begins propagating as a stepped leader to ground. In these ‘divert’ mode cases, the relevant interstroke time from the prior RS in the channel to the SSL inception from that path is long, ranging from 105 to 204 ms in four visible cases. The alternative mode of SSL inception occurs when a dart leader reaches the end of a prior unsuccessful branch—of an earlier competing dart leader, stepped leader, or initial leader—then begins advancing as a stepped leader toward ground. In this more common ‘branch’ mode (85% of visible cases), there may be no portion of the subsequent RS channel that is shared with a prior RS channel. These two inception modes, and variations among them, can occur in different subsequent strokes of the same flash.
Numerical modelling of rough particle contacts subject to normal and tangential loading
Authors: Nadimi S. , Otsubo M. , Fonseca J. , O’Sullivan C. 
Published: October 2019

AbstractOur understanding of the mechanics of contact behaviour for interacting particles has been developed mostly assuming that surfaces are smooth. However, real particles of interest in engineering science are generally rough. While recent studies have considered the influence of roughness on the normal force–displacement relationship, surface roughness was quantified using only a single scalar measure, disregarding the topology of the surface. There are some conflicting arguments concerning the effect of roughness on the tangential or shear force–displacement relationship. In this study, optical interferometry data are used to generate the surface topology for input into a 3D finite element model. This model is used to investigate the sensitivity of the normal force–displacement response to the surface topology by considering different surfaces with similar overall roughness values. The effect of surface roughness on the tangential force–displacement relationship and the influence of loading history are also explored. The results indicate that quantifying roughness using a single value, such as the root mean square height of roughness,Sq, is insufficient to predict the effect of roughness upon stiffness. It is also shown that in the absence of interlocking, rough particle surfaces exhibit a lower frictional resistance in comparison with equivalent smooth surfaces.
Permeability of rock discontinuities and faults in the Triassic Sherwood Sandstone Group (UK): insights for management of fluvio-aeolian aquifers worldwide
Authors: Medici Giacomo , West L. Jared , Mountney Nigel P. , Welch Michael 
Published: October 2019

Abstract
Fluvio-aeolian sedimentary successions host groundwater aquifers at shallow depths (<~0.15 km), which overlie geothermal and shale-gas reservoirs, and nuclear waste repositories at intermediate depths (~0.15–2.0 km). Additionally, such deposits represent petroleum reservoirs at greater depths (~2.0–4.0 km). The need to improve conceptual understanding of the hydraulic behaviour of fluvial-aeolian sandstone successions over a large depth interval (~0–4 km) is important for socio-economic reasons. Thus, the hydraulic properties of the Triassic Sherwood Sandstone aquifer in the UK have been reviewed and compared to similar fluvio-aeolian successions. The ratio between well-scale and core-plug-scale permeability (Kwell-test/Kcore-plug) acts as a proxy for the relative importance of fracture versus intergranular flow. This ratio (which typically varies from ~2 to 100) indicates significant contribution of fractures to flow at relatively shallow depths (<~0.15 km). Here, permeability development is controlled by dissolution of calcite-dolomite in correspondence of fractures. The observed ratio (Kwell-test/Kcore-plug) decreases with depth, approaching unity, indicating that intergranular flow dominates at ~1 km depth. At depths ≥ ~1 km, dissolution of carbonate cement by rock alteration due to groundwater flow is absent and fractures are closed. Aeolian and fluvial deposits behave differently in proximity to normal faults in the Sherwood Sandstone aquifer. Deformation bands in aeolian dune deposits strongly compartmentalize this aquifer. The hydro-structural properties of fluvio-aeolian deposits are also controlled by mineralogy in fault zones. A relative abundance of quartz vs. feldspar and clays in aeolian sandstones favours development of low-permeability deformation bands.
Correction to: Semi-automatic segmentation from intrinsically-registered 18F-FDG–PET/MRI for treatment response assessment in a breast cancer cohort: comparison to manual DCE–MRI
Authors: Andreassen Maren Marie Sjaastad , Goa Pål Erik , Sjøbakk Torill Eidhammer , Hedayati Roja , Eikesdal Hans Petter , Deng Callie , Østlie Agnes , Lundgren Steinar , Bathen Tone Frost , Jerome Neil Peter 
Published: October 2019

The original version of this article unfortunately contained a mistake in Fig. 6.
Opening the black box of selection
Authors: Schreurs Sanne , Cleutjens Kitty , Collares Carlos F. , Cleland Jennifer , oude Egbrink Mirjam G. A. 
Published: October 2019

Abstract
Medical school selection is currently in the paradoxical situation in which selection tools may predict study outcomes, but which constructs are actually doing the predicting is unknown (the ‘black box of selection’). Therefore, our research focused on those constructs, answering the question: do the internal structures of the tests in an outcome-based selection procedure reflect the content that was intended to be measured? Downing’s validity framework was applied to organize evidence for construct validity, focusing on evidence related to content and internal structure. The applied selection procedure was a multi-tool, CanMEDS-based procedure comprised of a video-based situational judgement test (focused on (inter)personal competencies), and a written aptitude test (reflecting a broader array of CanMEDS competencies). First, we examined content-related evidence pertaining to the creation and application of the competency-based selection blueprint and found that the set-up of the selection procedure was a robust, transparent and replicable process. Second, the internal structure of the selection tests was investigated by connecting applicants’ performance on the selection tests to the predetermined blueprint using cognitive diagnostic modeling. The data indicate 89% overlap between the expected and measured constructs. Our results support the notion that the focus placed on creating the right content and following a competency-blueprint was effective in terms of internal structure: most items measured what they were intended to measure. This way of linking a predetermined blueprint to the applicants’ results sheds light into the ‘black box of selection’ and can be used to support the construct validity of selection procedures.
Changing trends in liver cancer incidence by race/ethnicity and sex in the US: 1992–2016
Authors: Salvatore Maxwell , Jeon Jihyoun , Meza Rafael 
Published: October 2019

Abstract

Purpose
Liver cancer incidence continues to increase while incidence of most other cancers is decreasing. We analyze recent and long-term trends of US liver cancer incidence by race/ethnicity and sex to best understand where to focus preventive efforts.

Methods
Liver cancer incidence rates from 1992 to 2016 were obtained from the Surveillance, Epidemiology, and End Results registry. Delay-adjusted age-standardized incidence trends by race/ethnicity and sex were analyzed using joinpoint regression. Age-specific incidence was analyzed using age-period-cohort models. Hepatitis C seroprevalence by cohort was calculated using National Health and Nutrition Examination Survey data.

Results
Liver cancer incidence has peaked in males and Asian or Pacific Islanders. Hispanic males, a high-incidence population, are experiencing a decrease in incidence, although not yet statistically significant. In contrast, incidence continues to increase in females, although at lower rates than in the 1990s, and American Indian/Alaska Natives (AI/ANs). Liver cancer incidence continues to be higher in males. Non-Hispanic Whites have the lowest incidence among racial/ethnic groups. Trends largely reflect differences in incidence by birth-cohort, which increased considerably, particularly in males, for those born around the 1950s, and continues to increase in females and AI/ANs. The patterns in males are likely driven by cohort variations in Hepatitis C infection.

Conclusions
Liver cancer incidence appears to have peaked among males. However, important differences in liver cancer trends by race/ethnicity and sex remain, highlighting the need for monitoring trends across different groups. Preventive interventions should focus on existing liver cancer disparities, targeting AI/ANs, females, and high-incidence groups.
A double dissociative study into the effectiveness of computational thinking
Authors: Calderon Ana C. , Skillicorn Deiniol , Watt Andrew , Perham Nick 
Published: October 2019

Abstract
We propose the first steps towards a rigorous analysis of the effectiveness of an emerging pedagogy, Computational Thinking. We found that two aspects of the pedagogy have a positive effect with regard to enhancing two cognitive processes, namely sequential thinking and in abstract thinking. Our data was gathered experimentally with a cohort of mixed-ability undergraduate students enrolled on three distinct courses. The study employed a mixed 2 × 2 factorial design with type of classroom intervention, measurements were taken at baseline and following delivery of computational thinking methodologies designed to focus on specific components of the pedagogy. The dependent variable was percentage improvement from baseline, and the analyses were conducted using 2 × 2 mixed ANOVA, an alpha criterion of p < .05 was adopted for all analyses. The specific components investigated were algorithmic thinking and abstraction, and we found a positive correlation between enhancements of sequentiality and abstract thinking.
Regularization by Architecture: A Deep Prior Approach for Inverse Problems
Authors: Dittmer Sören , Kluth Tobias , Maass Peter , Otero Baguer Daniel 
Published: October 2019

Abstract
The present paper studies so-called deep image prior (DIP) techniques in the context of ill-posed inverse problems. DIP networks have been recently introduced for applications in image processing; also first experimental results for applying DIP to inverse problems have been reported. This paper aims at discussing different interpretations of DIP and to obtain analytic results for specific network designs and linear operators. The main contribution is to introduce the idea of viewing these approaches as the optimization of Tikhonov functionals rather than optimizing networks. Besides theoretical results, we present numerical verifications.
Snapshot of proton pump inhibitors prescriptions in a tertiary care hospital in Switzerland: less is more?
Authors: Lenoir Camille , El Biali Myriam , Luthy Christophe , Grosgurin Olivier , Desmeules Jules Alexandre , Rollason Victoria 
Published: October 2019

AbstractBackgroundProton pump inhibitors are among the most widely prescribed drugs in the world, but more than half of the indications for prescription are unjustified. The misuse of this therapeutic class has heavy consequences such as additional health costs, adverse drug reactions following long-term use and gastric acid rebound when the proton pump inhibitor is discontinued.ObjectiveThe overprescription of proton pump inhibitors is therefore becoming a public health problem, which led us to evaluate their use within the Geneva University Hospitals.SettingPatients hospitalized in two divisions of the department of internal medicine of the Geneva University Hospitals on a single day.MethodsThis is a register-based cross-sectional study and it collected data about the prescription pattern of proton pump inhibitors by consulting the electronic records of patients included.Main outcome measureTo determine if the proton pump inhibitors prescription is made according to the market authorization and the available guidelines.ResultsHundred-eighty patients were included. 54% of patients were on proton pump inhibitors, 29% of whom had their treatment initiated at hospital. Of the indications for treatment, 72% were not justified and 63% of the justified indications did not have an adequate dosage. Therefore, in all patients with a proton pump inhibitor at hospital, only 11% had a justified indication with an adequate dose. Finally, 87% of known home prescriptions were renewed on admission and among them, 71% did not have a justified or possibly justified indication according to the guidelines.ConclusionIndication for treatment inside the hospital was not justified in 72% of patients and only 11% had a justified indication with an adequate dosage. Precise guidelines with evidence-based indications and adequate daily doses would help to correctly prescribe proton pump inhibitors. Moreover, patients should benefit from a thorough evaluation of their treatment.