bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extracellular adenosine enhances the ability of PMNs to kill Streptococcus pneumoniae by inhibiting IL-10 production
Authors: Siwapornchai Nalat , Lee James N , Tchalla Essi Y I , Bhalla Manmeet , Yeoh Jun Hui , Roggensack Sara E , Leong John M , Bou Ghanem Elsa N 
Published: February 2020

Abstract
Polymorphonuclear leukocytes (PMNs) are crucial for initial control of Streptococcus pneumoniae (pneumococcus) lung infection; however, as the infection progresses their persistence in the lungs becomes detrimental. Here we explored why the antimicrobial efficacy of PMNs declines over the course of infection. We found that the progressive inability of PMNs to control infection correlated with phenotypic differences characterized by a decrease in CD73 expression, an enzyme required for production of extracellular adenosine (EAD). EAD production by CD73 was crucial for the ability of both murine and human PMNs to kill S. pneumoniae. In exploring the mechanisms by which CD73 controlled PMN function, we found that CD73 mediated its antimicrobial activity by inhibiting IL-10 production. PMNs from wild-type mice did not increase IL-10 production in response to S. pneumoniae; however, CD73−/− PMNs up-regulated IL-10 production upon pneumococcal infection in vitro and during lung challenge. IL-10 inhibited the ability of WT PMNs to kill pneumococci. Conversely, blocking IL-10 boosted the bactericidal activity of CD73−/− PMNs as well as host resistance of CD73−/− mice to pneumococcal pneumonia. CD73/IL-10 did not affect apoptosis, bacterial uptake, and intracellular killing or production of antimicrobial neutrophil elastase and myeloperoxidase. Rather, inhibition of IL-10 production by CD73 was important for optimal reactive oxygen species (ROS) production by PMNs. ROS contributed to PMN antimicrobial function as their removal or detoxification impaired the ability of PMNs to efficiently kill S. pneumoniae. This study demonstrates that CD73 controls PMN antimicrobial phenotype during S. pneumoniae infection.
Spatial distribution of the level of return of extreme precipitation events in Northeast Brazil
Authors: Rodrigues Daniele T. , Gonçalves Weber A. , Spyrides Maria H. C. , Santos e Silva Cláudio M. , de Souza Diego O. 
Published: February 2020

AbstractThis study aimed to estimate levels of return of extreme daily precipitation events, associating them with natural disasters in Northeast Brazil (NEB), a region characterized by different climatic conditions and low rates of social and economic development. For this, generalized Pareto distribution (GPD) models were adjusted to the daily extreme precipitation data estimated by the Tropical Rainfall Measuring Mission (TRMM) 3B42 product of the multisatellite precipitation analysis for a period of 16 years (2000–2015). In addition, the estimates of the GPD model were compared using two data sources, TRMM and pluviometer. The investigation showed that the results of the GPD model estimated by means of the extreme data from the rain gauge and the TRMM were statistically the same, with 95% confidence. Thus, using the data referring to the 2,082 grid points of the TRMM, it was possible to map the spatial distribution of the estimates of the levels of return of extreme precipitation to the return periods of 2, 5 and 10 years, per seasonal period. In general, the results indicated that the intensity of expected extreme precipitation depends on the seasonal period and the place of occurrence of precipitation. The eastern NEB stood out as the region where the highest intensities of extreme precipitation are expected. Extreme precipitation values of up to 178 mm are expected in 2 years. The areas where natural disasters occurred in the years 2016, 2017 and 2018 are similar to those in which the highest rainfall intensities are expected. The results of this study can allow the evaluation of the spatial distribution of risks related to extreme precipitation events, and therefore, support the planning of regional public policies and environmental management for the prevention of natural disasters in NEB.
Shape is only a weak predictor of deep knee flexion kinematics in healthy and osteoarthritic knees
Authors: Lynch Joseph T. , Perriman Diana M. , Scarvell Jennie M. , Pickering Mark R. , Warmenhoven John , Galvin Catherine R. , Neeman Teresa , Besier Thor F. , Smith Paul N. 
Published: February 2020

AbstractTibiofemoral shape influences knee kinematics but little is known about the effect of shape on deep knee flexion kinematics. The aim of this study was to examine the association between tibiofemoral joint shape and kinematics during deep kneeling in patients with and without osteoarthritis (OA). Sixty‐one healthy participants and 58 patients with end‐stage knee OA received a computed tomography (CT) of their knee. Participants completed full flexion kneeling while being imaged using single‐plane fluoroscopy. Six‐degree‐of‐freedom kinematics were measured by registering a three‐dimensional (3D)‐static CT onto 2D‐dynamic fluoroscopic images. Statistical shape modeling and bivariate functional principal component analysis (bfPCA) were used to describe variability in knee shape and kinematics, respectively. Random‐forest‐regression models were created to test the ability of shape to predict kinematics controlling for body mass index, sex, and group. The first seven modes of the shape model up to three modes of the bfPCAs captured more than 90% of the variation. The ability of the random forest models to predict kinematics from shape was low, with no more than 50% of the variation being explained in any model. Furthermore, prediction errors were high, ranging between 24.2% and 29.4% of the data. Variations in the bony morphology of the tibiofemoral joint were weakly associated with the kinematics of deep knee flexion. The models only explained a small amount of variation in the data with high error rates indicating that additional predictors need to be identified. These results contribute to the clinical understanding of knee kinematics and potentially the expectations placed on high‐flexion total knee replacement design.
Clinicoradiographic markers of peri‐implantitis in cigarette‐smokers and never‐smokers with type 2 diabetes mellitus at 7‐years follow‐up
Authors: Alqahtani Fawaz , Alqhtani Nasser , Alkhtani Fahad , Devang Divakar Darshan , Al‐Kheraif Abdulaziz A. , Javed Fawad 
Published: February 2020

AbstractBackgroundIt is hypothesized that in the long‐term, (a) peri‐implant inflammatory variables (plaque index [PI], bleeding on probing [BOP], probing depth (PD) and crestal bone loss [CBL]) are worse in cigarette‐smokers (CS) and patients with type‐2 diabetes mellitus (T2DM) than never‐smokers (NS) without T2DM. The aim of the present 7‐year follow‐up clinical observational study was to assess the survival of dental implant in CS and NS with T2DM.MethodsStudy participants were divided into four groups based on glycemic status and self‐reported cigarette‐smoking habit: a) CS with T2DM; b) CS without T2DM; c) NS with T2DM; and d) NS without T2DM. Demographic information was collected using a questionnaire and hemoglobin A1c (HbA1c) levels were measured. Peri‐implant PI, BOP, PD, and CBL were measured. Sample‐size was estimated was statistical analysis was done using analysis of variance. P <0.01 was considered significant.ResultsIn total, 101 male patients were included. There was no significant contrast in age among the groups. Every partaker in the study groups had one dental implant placed in posterior maxilla or mandible. The mean HbA1c levels were significantly higher among CS (P <0.01) and NS (P <0.01) with T2DM than individuals without T2DM. Peri‐implant PI (P <0.01), PD (P <0.01), and CBL (P <0.01) were significantly higher among CS and NS with T2DM and CS without T2DM than NS without T2DM. Peri‐implant BOP was significantly higher among CS and NS with T2DM than CS and NS without T2DM (P <0.01).ConclusionsPeri‐implant inflammatory variables were worse among CS and NS with T2DM than NS without T2DM. A state of chronic hyperglycemia seems to be a stronger mediator of inflammation than cigarette smoking in patients with T2DM.
Differentiating various beef cuts using spatially offset Raman spectroscopy
Authors: Ostovar Pour Saeideh , Fowler Stephanie M. , Hopkins David L. , Torley Peter , Gill Harsharn , Blanch Ewan W. 
Published: February 2020

AbstractThe potential of spatially offset Raman spectroscopy (SORS) for distinguishing different beef cuts was investigated. Six different retail beef cuts (rump, Scotch fillet, round, chuck, tenderloin, and T‐bone) were analysed spectroscopically using SORS. This technique makes it possible to measure the Raman signal 5 mm below the surface of meat muscles, allowing non‐invasive analysis of meat samples that are not readily feasible using conventional Raman spectroscopy. This study has shown for the first time that monitoring of the changes in glycogen, fat, and protein content of muscles can be investigated directly and, most importantly, non‐invasively within various meat cuts. The spectral results reveal differences in structure‐sensitive bands from the amide I and III regions as well as from cysteine, glutamic acid, and phenylalanine vibrations. Statistical analysis confirms these observations based on strong clustering of SORS bands (this was derived from principal component analysis scores of the SORS data) measured for the different cuts.
Use of Supplementary Feeding Dispensers by Arctic Foxes in Norway
Authors: Thierry Anne‐Mathilde , De Bouillane De Lacoste Nathalie , Ulvund Kristine , Andersen Roy , MeÅs Roger , Eide Nina E. , Landa Arild 
Published: February 2020

ABSTRACTSupplementary feeding is often used as a conservation tool to reverse the decline of food‐limited populations. The arctic fox (Vulpes lagopus) is one of the most endangered mammals in Norway and has been the target of several conservation initiatives for almost 3 decades, including supplementary feeding. To measure and improve the efficiency of supplementary feeding as a conservation action, we used passive integrated transponder (PIT)‐tags in arctic foxes and 6 feeding stations equipped with PIT‐tag readers to monitor individual use of supplemental food between 2013 and 2018. We tested hypotheses about the potential influence of temporal and spatial patterns, individual characteristics (i.e., age, sex, reproductive status), and food abundance (abundance of small rodents and amount of food filled) on the frequency and intensity of use of supplementary feeding stations by arctic foxes. The feeding stations were visited ≥1 time by 196 PIT‐tagged individuals. We detected 54% of juveniles born in the study area between 2013 and 2017 at the feeding stations. More arctic foxes used the feeding stations during the pre‐breeding period than during the other seasons, and the visits occurred mostly at night. The closest feeding station to each natal den was systematically used by the established pair and by the juveniles born at this den. Juveniles did not use the feeding stations more than adult foxes. Older foxes, and breeding adults, visited the feeding stations more than younger and non‐breeding adults. Foxes used feeding stations more intensively when prey was scarce and with greater amounts of supplemental food. This study highlights that supplemental feeding is important for breeding adults, especially in periods of low prey abundance. Understanding the use of feeding stations will contribute to the optimization of supplemental feeding as a conservation action and help wildlife managers to carefully plan and manage its discontinuation. © 2020 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.
Linear viscoelastic behavior of asphalt mixes from dynamic frequency response functions
Authors: Carret Jean‐Claude , Di Benedetto Herve , Sauzeat Cedric 
Published: February 2020

SummaryIn the small strain domain, asphalt mixes (AM) have a linear viscoelastic (LVE) behavior that is strongly dependent on frequency and temperature. The maximum ratio of modulus values can be up to 1000, and traditional elastic analyses are not pertinent. The possibility to characterize AM from frequency response functions (FRFs) was studied. A new optimization process using the finite element method (FEM) has been developed to back‐calculate the LVE properties of AM from FRFs. The numerical optimization process was applied to a reference material with averaged LVE properties determined from tension‐compression tests performed on a wide variety of AM types. The LVE properties were modeled considering the 3‐Dim version of the model 2S2P1D (2 Springs, 2 Parabolic elements, and 1 Dashpot). Reference FRFs for the considered reference material were obtained from FEM simulations. Three different configurations that may be of interest for practical tests were studied at five different temperatures. The proposed numerical optimization method consists in performing separate optimizations at each temperature to obtain the LVE properties for the considered temperature. Then values obtained at each temperature are considered to optimize 2S2P1D and Williams Landel Ferry (WLF) Equation constants to simulate the global LVE behavior of the material. The accuracy of the process was assessed regarding both the calculated FRFs and the complex modulus evaluation. Results indicate that the proposed optimization process converges almost perfectly towards the reference FRFs. The simulated complex modulus values are also in very good agreement with the values of the reference material.
On efficient algorithms for finding efficient salvo policies
Authors: van Ee Martijn 
Published: February 2020

AbstractWe consider the salvo policy problem, in which there are k moments, called salvos, at which we can fire multiple missiles simultaneously at an incoming object. Each salvo is characterized by a probability pi: the hit probability of a single missile. After each salvo, we can assess whether the incoming object is still active. If it is, we fire the missiles assigned to the next salvo. In the salvo policy problem, the goal is to assign at most n missiles to salvos in order to minimize the expected number of missiles used. We consider three problem versions. In Gould's version, we have to assign all n missiles to salvos. In the Big Bomb version, a cost of B is incurred when all salvo's are unsuccessful. Finally, we consider the Quota version in which the kill probability should exceed some quota Q. We discuss the computational complexity and the approximability of these problem versions. In particular, we show that Gould's version and the Big Bomb version admit pseudopolynomial time exact algorithms and fully polynomial time approximation schemes. We also present an iterative approximation algorithm for the Quota version, and show that a related problem is NP‐complete.
The role of cold crystallization of homochiral crystallites in the superb heat resistant poly(lactic acid)
Authors: Zhao Caixia , Yu Miaomiao , Fan Qicheng , Zou Guoxiang , Li Jinchun 
Published: February 2020

AbstractThe superb heat resistance poly(lactic acid) (PLA) were prepared by blending PLA and poly(d‐lactic acid) (PDLA) with various molecular weight (Mn). Formation of the stereocomplex in the blends was confirmed by differential scanning calorimetry and wide‐angle X‐ray diffraction. The results of the heat resistance implied it is possible that elevating the Vicat penetration temperature of PLA up to 150°C by blending with PDLA. The cold crystallization of homochiral crystallites is proven to be the critical factor affecting the heat resistance of PLA. While the PLA or PLA/PDLA blends were heated to cold crystallization temperature of samples, both the crystal content and the rigid amorphous region content are increased due to the cold crystallization and tethering effect, and the stiffness and heat resistance of the sample are improved. The cold crystallization homochiral crystallites kinetics of PLA and PLA/PDLA blends was also studied. The results showed the activation energy (∆E) of cold crystallization increased from 120.30 kJ/mol to 144.66 kJ/mol with the increasing of PDLA content from 2% to 10%.
Reutilization of waste printed circuit boards nonmetallic powders in elastomer composites: Significant improvements of curing and mechanical properties
Authors: Hu Dechao , Luo Yuanfang , Lin Jing , Chen Yongjun , Jia Demin 
Published: February 2020

AbstractRecycling of waste printed circuit boards nonmetallic powders (WPCBPs), as one of the significant challenges for sustainable development of resources, has attracted tremendous attentions from scientific and industrial researchers. In this work, the feasibility of WPCBP as curing accelerator and reinforcing filler in styrene‐butadiene rubber (SBR) composites was first explored. Vulcanization parameters and kinetics of SBR compounds were systematically investigated by moving‐die rheometer and differential scanning calorimeter. The results suggested that the incorporation of WPCBP can effectively reduce vulcanization activation energy and shorten the manufacturing cycle of SBR/SiO2 composites, which may be attributed to the activation effect from metal oxide and accelerating effect from residual additives in WPCBP. On the other hand, the coupling interfacial interactions of rubber‐SiO2 and rubber‐WPCBP result in simultaneous enhancements of tensile strength, tensile modulus, and extensibility of SBR/SiO2/WPCBP composites. Moreover, the potential applications and challenges of SBR/SiO2/WPCBP composites were also briefly analyzed. This work offers a green and efficient reutilization approach of WPCBP in elastomer composites, which may be a valuable inspiration for the high‐valued utilization of WPCBP and the preparation of high‐performance and low‐cost elastomer composites.
The effect of Ag@SiO2 core‐shell nanoparticles on the dielectric properties of PVDF based nanocomposites
Authors: Weng Ling , Wang Xiaoming , Zhang Xiaorui , Guan Lizhu , Liu Lizhu , Zhang Hexin , Cui Weiwei 
Published: February 2020

AbstractHigh dielectric properties material has a profound influence on the development of electronic power system, polymer based composites obtained a great number of achievements on it. A new strategy, which covered a layer of insulation on the surface of the inorganic particles to form a core‐shell structure, then used it for composites is a good choice. In this article, a series of PVDF based nanocomposite with different contents were prepared by using PVDF flexible polymer as substrate and core‐shell structure Ag@SiO2 nanoparticles as fillers. The effects of Ag@SiO2 core‐shell nanoparticles on the structure and properties of composites were investigated. Results showed that Ag@SiO2 has a typical core‐shell structure and the diameter size of Ag@SiO2 nanoparticles is 100 nm in average with about 20 nm thickness of SiO2 shell. XRD analysis showed that the addition of Ag@SiO2 nanoparticles induce a transition on crystal structure of PVDF from multiphase to mainly β phase, which result in an improvement on ferroelectric properties of composites. Broadband dielectric spectroscopy results indicate that the dielectric constant and dielectric loss of nanocomposites are positively correlated with the filler's contents. The tested dielectric constant of composites increase from 8.42 (5 wt% fillers content) to 10.1 (20 wt% fillers' content), coupled with an increase on electrical breakdown strength from 21.22 to 31.46 kV/mm. The calculated energy density also increases from 0.016777 to 0.044234 J/cm3.
Further criterion for stochastic stability analysis of semi‐Markovian jump linear systems
Authors: Jiang Baoping , Karimi Hamid Reza 
Published: February 2020

SummaryThis article is devoted to provide further criterion for stochastic stability analysis of semi‐Markovian jump linear systems (S‐MJLSs), in which more generic transition rates (TRs) will be studied. As is known, the time‐varying TR is one of the key issues to be considered in the analysis of S‐MJLS. Therefore, this article is to investigate general cases for the TRs that covered almost all types, especially for the type that the jumping information from one mode to another is fully unknown, which is merely investigated before. By virtue of stochastic functional theory, sufficient conditions are developed to check stochastic stability of the underlying systems via linear matrix inequalities formulation combined with a maximum optimization algorithm. Finally, a numerical example is given to verify the validity and effectiveness of the obtained results.
Numerical simulations of fatigue loads on wind turbines operating in wakes
Authors: Liu Zhenqing , Li Qiuming , Ishihara Takeshi , Peng Jie 
Published: February 2020

AbstractWake effects increase the fatigue loads on wind turbines in operation. However, the wake flow is considerably different from the traditional boundary layer flow, and poses many challenges in determining the fatigue loads on wind turbines operating in a wake. Therefore, in the present study, the actuator‐line model was adopted to numerically simulate the wake flow and an in‐house code named AOWT, which is based on a generalized coordinate method, was developed for analyzing the dynamics of wind turbines under an arbitrary distribution of the turbulent flow field varying in time and space. Using the numerically modeled instantaneous wake flow fields and AOWT, the dynamic response of a wind turbine, located at specified positions in both tandem and staggered arrangements in a wake, was examined, and the fatigue loads were determined. Furthermore, to determine the major contributions to the fatigue loads, the loads induced by the spatial variation of the mean flow fields were predicted. To the best of the authors' knowledge, no such analysis has been conducted thus far. Importantly, it was found that in the near‐wake region, the mean flow field had a significant influence on the fatigue loads, especially in the staggered layout. However, there is no analytical wake model available in the literature capable of predicting the near‐wake mean flow fields. Therefore, in this study, a near‐wake model was proposed, which yielded satisfactory predictions of the mean velocities in the near‐wake region.
Weak–Strong Uniqueness for the Navier–Stokes Equation for Two Fluids with Surface Tension
Authors: Fischer Julian , Hensel Sebastian 
Published: February 2020

AbstractIn the present work, we consider the evolution of two fluids separated by a sharp interface in the presence of surface tension—like, for example, the evolution of oil bubbles in water. Our main result is a weak–strong uniqueness principle for the corresponding free boundary problem for the incompressible Navier–Stokes equation: as long as a strong solution exists, any varifold solution must coincide with it. In particular, in the absence of physical singularities, the concept of varifold solutions—whose global in time existence has been shown by Abels (Interfaces Free Bound 9(1):31–65, 2007) for general initial data—does not introduce a mechanism for non-uniqueness. The key ingredient of our approach is the construction of a relative entropy functional capable of controlling the interface error. If the viscosities of the two fluids do not coincide, even for classical (strong) solutions the gradient of the velocity field becomes discontinuous at the interface, introducing the need for a careful additional adaption of the relative entropy.