bluuebunny/crossref_metadata_2025_split huggingface dataset:
Smoothed particle hydrodynamic modelling of the cerebrospinal fluid for brain biomechanics: Accuracy and stability
Authors: Duckworth Harry , Sharp David J. , Ghajari Mazdak 
Published: January 2021

AbstractThe Cerebrospinal Fluid (CSF) can undergo shear deformations under head motions. Finite Element (FE) models, which are commonly used to simulate biomechanics of the brain, including traumatic brain injury, employ solid elements to represent the CSF. However, the limited number of elements paired with shear deformations in CSF can decrease the accuracy of their predictions. Large deformation problems can be accurately modelled using the mesh‐free Smoothed Particle Hydrodynamics (SPH) method, but there is limited previous work on using this method for modelling the CSF. Here we explored the stability and accuracy of key modelling parameters of an SPH model of the CSF when predicting relative brain/skull displacements in a simulation of an in vivo mild head impact in human. The Moving Least Squares (MLS) SPH formulation and Ogden rubber material model were found to be the most accurate and stable. The strain and strain rate in the brain differed across the SPH and FE models of CSF. The FE mesh anchored the gyri, preventing them from experiencing the level of strains seen in the in vivo brain experiments and predicted by the SPH model. Additionally, SPH showed higher levels of strains in the sulci compared to the FE model. However, tensile instability was found to be a key challenge of the SPH method, which needs to be addressed in future. Our study provides a detailed investigation of the use of SPH and shows its potential for improving the accuracy of computational models of brain biomechanics.
Gamma — General Abstract Model for Multiset mAnipulation and dynamic dataflow model: An equivalence study
Authors: Mello Rui R. , de Araújo Leandro S. , Alves Tiago A. O. , Marzulo Leandro A. J. , Paillard Gabriel A. L. , França Felipe M. G. 
Published: January 2021

AbstractWith the increase of the search for computational models where the expression of parallelism occurs naturally, some paradigms arise as options for the current generation of computers. In this context, dynamic dataflow and Gamma—GeneralAbstractModel forMultiset mAnipulation—emerge as interesting computational model choices. In dynamic dataflow model, operations are performed as soon as their associated operands are available, without rely on a Program Counter to dictate the execution order of instructions. The Gamma paradigm is based on a parallel multiset rewriting scheme. It provides a nondeterministic execution model inspired by anabstract chemical machinemetaphor, where operations are formulated as reactions that occur freely among matching elements belonging to the multiset. In this work, equivalence relations between the dynamic dataflow and Gamma paradigms are exposed and explored, while methods to convert from dataflow to Gamma paradigm and vice versa are provided. It is shown that vertices and edges of a dynamic dataflow graph can correspond, respectively, to reactions and multiset elements in the Gamma paradigm. This work provides the scientific community with the possibility of taking profit of both parallel programming models, contributing with a versatility component to researchers and developers.
Genetic diversity and agronomic performance of wheat landraces currently grown in Tajikistan
Authors: Husenov Bahromiddin , Muminjanov Hafiz , Dreisigacker Susanne , Otambekova Munira , Akin Beyhan , Subasi Kemal , Rasheed Awais , Shepelev Sergey , Morgounov Alexey 
Published: January 2021

AbstractTajikistan is rich in genetic resources and one of a few countries where farmers still grow wheat (Triticum spp) landraces, which are important for production and breeding. This study undertook morphological description and agronomic and genomic characterization of wheat landraces collected in Tajikistan in 2013 and 2014 to develop opportunities for their use in breeding and on‐farm maintenance. In total, 60 wheat landraces were collected from 40 villages in 14 administrative districts and four regions. They were evaluated for agronomic traits in field trials in Turkey. The study identified six distinct regions where landraces are still grown. The villages growing the landraces were remote, with the distance to the nearest market being 30–100 km. The area allocated to wheat landraces varied from 0.01 to 2 ha. The main reason for maintaining the wheat landraces was their suitability for homemade bread and specific adaptation to high altitude. Overall, 68 distinct lines originating from landraces were identified using morphological and genomic descriptions. A core set of 30 lines was selected and field phenotyped under rain‐fed conditions. Several landraces (Joydori, Safedak, Surkhaki besuk, Shukhak, Surkh‐suk, and Kilaki bartang) that exceeded local check for grain yield and size were identified. Cluster analysis using single nucleotide polymorphism (SNP) array kinship matrix demonstrated relatedness between the landraces from different regions of Tajikistan and from neighboring regions of Uzbekistan. The value of this study for the international community is in conservation of rare and unique wheat landraces that could have been lost in the future.
Investigation of Voltage Range and Self‐Discharge in Aqueous Zinc‐Ion Hybrid Supercapacitors
Authors: Yang Jie , Bissett Mark A. , Dryfe Robert A. W. 
Published: January 2021

AbstractAqueous zinc‐ion hybrid supercapacitors are a promising energy storage technology, owing to their high safety, low cost, and long‐term stability. At present, however, there is a lack of understanding of the potential window and self‐discharge of this aqueous energy storage technology. This study concerns a systematic investigation of the potential window of this device by cyclic voltammetry and galvanostatic charge–discharge. Hybrid supercapacitors based on commercial activated carbon (AC) demonstrate a wide and stable potential window (0.2 V to 1.8 V), high specific capacitances (308 F g−1 at 0.5 A g−1 and 110 F g−1 at 30 A g−1), good cycling stability (10000 cycles with 95.1 % capacitance retention), and a high energy density (104.8 Wh kg−1 at 383.5 W kg−1), based on the active materials. The mechanism involves simultaneous adsorption–desorption of ions on the AC cathode and zinc ion plating/stripping on the Zn anode. This work leads to better understanding of such devices and will aid future development of practical high‐performance aqueous zinc‐ion hybrid supercapacitors based on commercial carbon materials, thus accelerating the deployment of these hybrid supercapacitors and filling the gap between supercapacitors and batteries.
A Complementary Co−Ni Phosphide/Bimetallic Alloy‐Interspersed N‐Doped Graphene Electrocatalyst for Overall Alkaline Water Splitting
Authors: Arunkumar Paulraj , Gayathri Sampath , Han Jong Hun 
Published: January 2021

AbstractEchinops‐like bimetallic CoNiP−CoNi alloy is synthesized from a metal−organic framework (MOF) and serves as an efficient catalyst for the oxygen evolution reaction (OER), with a low overpotential of 300 mV in 1 M KOH at 10 mA cm−2 (η10). The cooperative effect of Ni and Co metal, as well as the interfacial properties of the integrated semiconducting phosphide/metallic alloy and electronic conductivity of the MOF‐derived carbon regulate the performance of the catalyst. Moreover, the bimetallic CoNiP/CoNi alloy catalyst is interspersed with N‐doped graphene, forming a triad catalyst that demonstrates superior activity towards the hydrogen evolution reaction (η10=150 mV) and excellent durability, owing to interfacial effects of the triad catalyst, large electrochemical active surface area, and enhanced conductivity from N‐doped graphene. The stability of the carbon‐containing catalyst during OER (oxidation) is altered by the high reactivity of heteroatom dopant. The assembled CoNiP/CoNi/N−RGO||CoNiP/CoNi water electrolyzer delivers a reasonable cell potential of 1.76 V at 10 mA cm−2. The synthesized bimetallic CoNiP/CoNi alloy‐based triad catalyst thus demonstrates excellent electrocatalytic activity and high durability suitable for efficient alkaline water splitting.
Simulations of filamentary structure in an edge‐localized mode burst on EAST using BOUT++ code
Authors: Wu Y.B. , Xia T.Y. , Zhong F.C. ,   EAST Team
Published: January 2021

AbstractIn this paper, simulation on the filamentary structure for the low‐hybrid wave heating H‐mode on experimental advanced superconducting tokamak (EAST) is carried out for the first time using BOUT++, and the speed and width of edge localized mode (ELM) filaments have been evaluated during the simulation. The evolutions of the ELM filaments are illustrated temporally and spatially. Then the results are compared with the experimental observations. It is found that at the peak gradient region in the outer midplane, the radial speed of the filaments is changed frequently and varied from 0.016 to 0.38 km/s. For the contrast, the poloidal speed oscillates in a narrower range of 0.68–0.88 km/s. The calculation results show the width of ELM filaments oscillates during the simulation, the minimum width is around 8.3 mm, and the maximum value is 41.24 mm. The distributions of the ELM filament widths with the radial position indicate the width is decreased with the radial position. Furthermore, by tracing one single filament, the radial width is decreased gradually when the filament is moving outward, which is also consistent with experiment conclusion. The consistencies also indicate the availability and practicability of the six‐field two‐fluid model of BOUT++ on the study of ELMs.
Better boundaries: identifying the upper extent of fish distributions in forested streams using eDNA and electrofishing
Authors: Penaluna Brooke E. , Allen Jennifer M. , Arismendi Ivan , Levi Taal , Garcia Tiffany S. , Walter Jason K. 
Published: January 2021

AbstractThe management of species that occur in low densities is a conservation concern worldwide across taxa with consequences for managers and policymakers. The distribution boundary at the upper extent of fish in North America receives extra attention because stream reaches with fish are managed differently and often have more protections than fishless reaches. Here, we examine the relative reliability of water environmental DNA (eDNA), polymerase chain reaction (PCR)‐amplified for Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) to detect the upper extent of fish across streams as a potential management tool compared to standard electrofishing methods. We provide estimates of fish detection probabilities from eDNA analyses, and probabilities of detection for both eDNA field samples and quantitative PCR (qPCR) given covariates of habitat characteristics and fish densities from electrofishing. We present a primer and probe based on the cytochrome oxidase I gene using qPCR to detect trout DNA across water samples from 60 forested streams in the Pacific Northwest, USA using high‐resolution spatial sampling. In 28% of streams, the upper extent of fish matches between methods. In over half of the streams, Coastal Cutthroat Trout eDNA was detected above the electrofishing last‐fish boundary. Although some detections could be attributed to false‐positive errors, eDNA results extend the upstream, leading edge of fish by 50–250 m from the electrofishing boundary. In 20% of the streams, detections of last‐fish occurred higher in the stream network with electrofishing rather than eDNA, but generally by only 50 m. Modeled results revealed that the occurrence of trout eDNA was higher in wider‐stream locations and that eDNA detections occurred at lower electrofishing densities (<5 trout per 50 linear m). We also showed that three replicate eDNA samples were sufficient to capture trout eDNA when eDNA was present. Although eDNA constitutes an effective addition to approaches to delimit the upper extent of fish, its effectiveness depends on previous knowledge of the last‐fish boundary to apprise where to start sampling and targeting fish species anticipated to be last‐fish. We present evidence that eDNA is a valuable tool in investigating fish distributions taking its place alongside traditional high‐effort catch–release tools.
Nitrogen acquisition strategies of mature Douglas‐fir: a case study in the northern Rocky Mountains
Authors: Qubain Claire A. , Yano Yuriko , Hu Jia 
Published: January 2021

AbstractNitrogen (N) limits plant growth in temperate ecosystems, yet many evergreens exhibit low photosynthetic N use efficiency, which can be explained in part by their tendency to store more N than to use it in photosynthesis. However, it remains uncertain to what extent mature conifers translocate internal N reserves or take up N from soils to support new growth. In this study, we explored N dynamics within mature Douglas‐fir (Pseudotsuga menziesii var. glauca) trees by linking N uptake in field‐grown trees with seasonal soil available N. We used a branch‐level mass balance approach to infer seasonal changes in total N among multiple needle and stem cohorts and bole tissue, and used foliar δ15N to evaluate N translocation/uptake from soils. Soil resin‐exchangeable N and net N transformation rates were measured to assess whether soils had sufficient N to support new needle growth. We estimated that after bud break, new needle biomass in Douglas‐fir trees accumulated an average of 0.20 ± 0.03 mg N/branch and 0.17 ± 0.03 mg N/branch in 2016 and 2017, respectively. While we did find some evidence of translocation of N from older stems to buds prior to bud break, we did not detect a significant drawdown of N from previous years’ growth during needle expansion. This suggests that the majority of N used for new growth was not reallocated from aboveground storage, but originated from the soils. This finding was further supported by the δ15N data, which showed divergent δ15N patterns between older needles and buds prior to leaf flushing (indicative of translocation), but similar patterns of depletion and subsequent enrichment following leaf expansion (indicative of N originating from soils). Overall, in order to support new growth, our study trees obtained the majority of N from the soils, suggesting tight coupling between soil available N and N uptake in the ecosystem.
Impacts of a drought and hurricane on tropical bird and frog distributions
Authors: Campos‐Cerqueira Marconi , Aide T. Mitchell 
Published: January 2021

AbstractDuring the last few decades, much attention has focused on how global change is affecting the environment and species distributions. Land‐use change is still the major cause of species declines worldwide, but changes in species distributions have been documented even in pristine and protected areas. Here, we document the distribution dynamics of 26 species of frogs and birds within a Caribbean protected area between 2015 and 2019. Specifically, we document species occupancy and detectability in 59 sites along three elevational transects within the El Yunque National Forest in Puerto Rico. Species were sampled using acoustic recorders, species identification algorithms, and post‐classification validation. The study period included a severe drought (2015–2016) and a category 4 hurricane (2017). The distribution of most frog species did not change significantly during the study period. In contrast, the distributions of the bird species contracted between the 2015 and 2016 pre‐hurricane surveys. This contraction coincides with a severe drought that peaked after the 2015 survey. The response of bird species after H. Maria was heterogeneous. Our results suggest that for many species, particularly birds, the 2015–2016 drought in Puerto Rico had a greater negative effect than H. Maria. The difference in the response of the bird and frog communities is likely related to their abundance at the site level, their ability to disperse, and temporal patterns of reproduction. If a site is occupied by a frog species, it could easily include 100s of individuals, and even if condition worsens, over a relatively short period the species will continue to occupy the site. In contrast, a site may only be occupied by one or a few individuals of birds. Birds have also higher dispersal abilities than frogs. Furthermore, Puerto Rican frogs reproduce year‐round, whereas birds concentrate their reproduction during a few months in the wet season. Future climate scenarios predict a decrease in total precipitation and an increase in droughts for the region, which emphasizes the need to consider the diversity of changes that will be associated with future climate change.
Hospitalization for hypoglycaemia in people with diabetes in Denmark, 1997–2017: Time trends in incidence and HbA1c and glucose‐lowering drug use before and after hypoglycaemia
Authors: Bengtsen Mads Bisgaard , Knudsen Jakob Schöllhammer , Bengtsen Maria Bisgaard , Møller Niels , Thomsen Reimar Wernich 
Published: January 2021

AbstractObjectiveTo assess incidence trends of first hospitalization for hypoglycaemia in Denmark and to examine HbA1c levels and glucose‐lowering drug use before and after hospitalization among individuals with type 1 or type 2 diabetes.Research Design and MethodsWe performed a population‐based study linking diagnosis, prescription and laboratory data. Standardized incidence of first hospitalization for hypoglycaemia in Denmark was assessed for each calendar year 1997–2017. HbA1c and glucose‐lowering drug use was compared with age‐ and sex‐matched diabetes comparisons without hospitalization for hypoglycaemia.ResultsThe annual age‐ and sex‐standardized incidence rate of first hospitalization for hypoglycaemia per 100,000 person‐years increased during 1997–2003 (from 17.7 to 30.3 per 100,000 person‐years), remained stable until 2010 (30.4) and gradually declined until 2017 (22.0). During this period, we identified 3,479 people with type 1 diabetes and 15,329 people with type 2 diabetes experiencing first hospitalization for hypoglycaemia. Both diabetes groups experienced a mean HbA1c decrease of ~12%–15% in the months preceding first hospitalization, followed by a gradually increasing HbA1c afterwards. People with type 1 diabetes and hospitalization used similar insulin therapies as those without hospitalization. People with type 2 diabetes and hospitalization more often received insulin (55%) than comparisons (45%), and 45% discontinued insulin or stopped all glucose‐lowering therapy after first hospitalization.ConclusionsIncidence of hospitalizations for hypoglycaemia has declined by one fourth the last decade in the Danish population. A HbA1c decrease precedes first hospitalization for hypoglycaemia in individuals with diabetes, and profound changes in glucose‐lowering drug therapy for type 2 diabetes occur after hospitalization.
Influence of abutment straight backwall fracture on the seismic response of bridges
Authors: Zheng Qiu , Yang Chuang‐Sheng Walter , Xie Yazhou , Padgett Jamie , DesRoches Reginald , Roblee Cliff 
Published: January 2021

AbstractField reconnaissance reports reveal the seismic vulnerability of bridge abutment foundations. To reduce the time and cost of postearthquake repair, modern seismic design specifications allow abutment backwalls to fracture before the supporting abutment foundations reach their maximum strength. This design strategy enables abutment backwalls to function as a fuse, thus protecting the abutment foundations from experiencing excessive forces and damage. This paper introduces a new abutment modeling scheme to capture the shear fracture mechanism of straight backwalls in seat abutments. To this end, a backwall connection spring is developed and incorporated into a spring system that simulates the behavior of various abutment components. The importance of considering the backwall fracture is examined by reviewing conventional modeling methodologies for abutments and building companion numerical models. Static pushover and incremental dynamic analyses (IDAs) were conducted for two bridges (single‐ and two‐span) modeled by both the proposed and conventional abutment modeling schemes. Moreover, component‐level fragility curves are developed using IDA results. The comparisons show that the conventional abutment modeling schemes significantly overestimate abutment foundation damage and underestimate the likelihood of deck unseating, column damage, and bearing displacement in the passive direction. Conversely, the proposed modeling scheme is able to capture the essential seismic responses of various components in seat abutment bridges. The consideration of backwall fracture in the modeling of abutment components enables a more rational seismic response assessment of bridges with backwalls, which are likely to be damaged during earthquakes, particularly for bridges which are seismically designed to protect abutment foundations.
Testing bias in professional forecasts
Authors: Franses Philip Hans 
Published: January 2021

AbstractProfessional forecasters can rely on econometric models, on their personal expertise or on both. To accommodate for adjustments to model forecasts, this paper proposes to use two stage least squares (TSLS) (and not ordinary least squares [OLS]) for the familiar Mincer–Zarnowitz regression when examining bias in professional forecasts, where the instrumental variable is the consensus forecast. An illustration for 15 professional forecasters with their quotes for real gross domestic product (GDP) growth, inflation and unemployment for the United States documents the usefulness of this new estimation method. It also shows that TSLS suggests less bias than OLS does.
Digitalization and globalization in a turbulent world: Centrifugal and centripetal forces
Authors: Autio Erkko , Mudambi Ram , Yoo Youngjin 
Published: January 2021

AbstractResearch SummaryDigitalization has three fundamental characteristics, reprogrammability infrastructural elementality, and intangibility. Based on these characteristics, it is transforming how firms organize for value creation, delivery, and capture. Its intangibility and infrastructural character largely free economic and business activities from the constraints of physical geography like those imposed by transportation and collocation. Digital communication technologies typically reinforce the centrifugal forces that favor dispersing the firm's high knowledge activities. Digital in situ technologies strengthen the centripetal forces toward concentrating the firm's low knowledge activities. Location dependence and product modularity are crucial moderators for tangible products, while institutional barriers are important for intangible ones. Finally, digital technologies increase the resilience of firms during disruptive events that impose restrictions on the movements of people and goods, as during the COVID‐19 pandemic.Managerial SummaryDigitalization is a general purpose technology on the scale of the steam engine and electricity, and affects every aspect of business and society. It is transforming how firms organize for value creation, delivery, and capture. Freeing businesses from the constraints of transportation and collocation, it increases their resiliency in the face of global disruptions like those associated with the COVID‐19 pandemic. Digital communication technologies typically reinforce the centrifugal forces that favor dispersing the firm's high knowledge activities. Digital in situ technologies like advanced robotics strengthen the centripetal forces toward concentrating the firm's low knowledge activities. Location dependence and product modularity are crucial moderators for tangible products, while institutional barriers are important for intangible ones.