bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acoustic measurements of marine sediments with pebbles and cobbles
Authors: Holland Charles W. , Dettmer Jan , Steininger Gavin , Dosso Stan E. , Lowrie Allen 
Published: December 2019

ABSTRACTThe majority of sediment acoustics research has focused to date on sediments with sand‐sized particles or smaller; measurements for sediments containing cobbles (6–26 cm) are rare. This paper presents the first measurements (to the authors’ knowledge) over a wide frequency range of compressional‐wave velocity and bulk density for a sediment with cobbles. The in situ velocity from inversion from wide‐angle reflection‐coefficient data at 0.4–2 kHz for cobbles suspended in sand is found here to be 1800 m/s with 95% credibility interval bounds of [1787–1828] m/s and for cobbles suspended in clay 1532 [1528–1536] m/s. Measured core velocities at 50 kHz and 200 kHz are lower for each sediment due to multiple scattering. The in situ bulk density for cobbles suspended in sand is 2.25 [2.21–2.28] g/cm3 and for cobbles suspended in clay 1.83 [1.78–1.87] g/cm3. Though cobbles in the upper few metres of sediment may be considered unusual on the mid‐shelf at mid‐latitudes, they appear to be present over tens of square kilometres on the Malta Plateau in a several metre thick layer starting at about 1 m below seafloor. In fact, geologic process considerations suggest that cobbles may be generally more common in mid to outer shelf environments than the paucity of measurements would suggest. Increased interest in the Arctic continental shelf environment, where pebbles and cobbles are expected to be prevalent, provides an additional motivation for this work.
Polypropylene–nano‐silica nanocomposite foams: mechanisms underlying foamability, and foam microstructure, crystallinity and mechanical properties
Authors: Kumar Anish , Patham Bhaskar , Mohanty Smita , Nayak Sanjay Kumar 
Published: December 2019

AbstractWe investigate the production and characterization of foams prepared from polypropylene (PP) as well as PP–silica nanocomposites containing different loadings of nano‐silica. This study was carried out to investigate the mechanisms underlying the production of foams with a regular cell structure through the use of nano‐scale fillers. Foaming was carried out in batch mode using an autoclave with CO2 as the physical blowing agent; high pressures of the order of 14 MPa were achieved through a combination of active pressurization and the use of high foaming temperatures. The resulting PP nanocomposite foams were characterized in detail to quantify the effect of the nano‐silica loading on the foam density and mechanical, morphological and thermal properties. The addition of nano‐silica in PP resulted in the improvement of foam quality – as assessed from the well‐defined and regular cell structures with absence of cell coalescence – as well as an increase in expansion ratio and decrease in foam density. Careful analyses of trends in cell size, cell density and expansion ratio of the foams were correlated with measurements of melt rheology and nano‐filler morphology of the unfoamed specimens in order to identify subtle details regarding the role of silica nanoparticles in improving foam quality. © 2019 Society of Chemical Industry
Design and Damage Performance Ability of Supercavitation Projectile with Shaped Charge
Authors: Wang Kang‐Jian , Rong Guang , Yi Wen‐Jun 
Published: December 2019

AbstractThe traditional supercavitation projectile depends on its kinematics to damage targets. However, the bullet penetration ability is greatly restrained by the range. To improve the damage performance of underwater projectiles, the shaped charge and supercavitation technology are combined in this paper, which called shaped charge supercavitation projectile. The projectile is designed and analyzed through ANSYS/LS‐DYNA software in the preliminary stage. The simulation results turn out that the structures have many advantages with reasonable design. The paper divides the design into three steps: the first step is to design the shaped charge according to the requirements or shaped charge structure designed; the second step is to determine the optimum stand‐off that is obtained by numerical analysis. The stand‐off is set as the length of the projectile head; the third step is to calculate the cavitator diameter by the Logvinovich equation. These results will provide a new idea for the design of underwater weapons.
Improvement of m/z accuracy for linear matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometer
Authors: Yu Jiajun , Chudinov Alexey , Li Lei , Liu Jinzhao , Gao Wei , Huang Zhengxu , Zhou Zhen , Nikiforov Sergey , Kozlovskiy Viatcheslav 
Published: December 2019

RationaleLinear matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) is widely used in analytical and biomedical applications. The use of delayed extraction increases the resolution, but the roughness of the matrix crystals and the misalignment of the target plate in the order of a few micrometers cause a substantial spread in the ion TOF values and a decrease in mass accuracy.MethodsThe method of mass spectra correction based on the correlation of matrix fragment peaks in MALDI mass spectra was used. Experiments were performed using the MALDI‐TOF instrument CMI‐1600. SIMION 8.1 and MATLAB were used for ion motion simulations. Data analysis was done using the home‐built custom‐developed software and MATLAB.ResultsIt was shown that the peak position drift in the MALDI‐TOF mass spectra depends linearly on the TOF in a wide mass range. While using the linear correction of the TOF scale, an increase in m/z accuracy of more than 10 times was achieved. The mass accuracy was limited by the resolution of the fast Analog‐to‐Digital Converter (ADC) used.ConclusionsIt is expected that the proposed method will significantly increase the dynamic range, since it becomes possible to sum up corrected individual mass spectra without a significant loss of resolution. Timescale adjusting can be used for both linear TOF instruments and reflector systems of various configurations.
State‐limiting PID controller for a class of nonlinear systems with constant uncertainties
Authors: Konstantopoulos George C. , Baldivieso‐Monasterios Pablo R. 
Published: December 2019

SummaryProportional Integral Derivative (PID) controllers still represent the core control method for achieving output regulation of either linear or nonlinear systems in the majority of industrial applications. However, conventional PID control cannot guarantee specific state constraint requirements for the plant, when the system introduces uncertainties. In this paper, a novel nonlinear PID control that achieves output regulation and guarantees a desired state limitation below a given value for a wide class of nonlinear systems with constant uncertainties is proposed. Using nonlinear ultimate boundedness theory, it is shown that the proposed state‐limiting PID (sl‐PID) control maintains a given bound for the desired system states at all times, ie, even during transients, whereas an analytic method for selecting the controller gains is also presented to ensure closed‐loop system stability and convergence at the desired equilibrium. Two nonlinear engineering examples that include an electric motor and a dc/dc converter are investigated using the conventional PID and the proposed sl‐PID to validate the superiority of the proposed controller in achieving the desired output regulation with a given bounded state requirement.
Detecting northern peatland vegetation patterns at ultra‐high spatial resolution
Authors: Räsänen Aleksi , Aurela Mika , Juutinen Sari , Kumpula Timo , Lohila Annalea , Penttilä Timo , Virtanen Tarmo 
Published: December 2019

AbstractWithin northern peatlands, landscape elements such as vegetation and topography are spatially heterogenic from ultra‐high (centimeter level) to coarse scale. In addition to within‐site spatial heterogeneity, there is evident between‐site heterogeneity, but there is a lack of studies assessing whether different combinations of remotely sensed features and mapping approaches are needed in different types of landscapes. We evaluated the value of different mapping methods and remote sensing datasets and analyzed the kinds of differences present in vegetation patterns and their mappability between three northern boreal peatland landscapes in northern Finland. We utilized field‐inventoried vegetation plots together with spectral, textural, topography and vegetation height remote sensing data from 0.02‐ to 3‐m pixel size. Remote sensing data included true‐color unmanned aerial vehicle images, aerial images with four spectral bands, aerial lidar data and multiple PlanetScope satellite images. We used random forest regressions for tracking plant functional type (PFT) coverage, non‐metric multidimensional scaling ordination axes and fuzzy k‐medoid plant community clusters. PFT regressions had variable performance for different study sites (R2 −0.03 to 0.69). Spatial patterns of some spectrally or structurally distinctive PFTs could be predicted relatively well. The first ordination axis represented wetness gradient and was well predicted using remotely sensed data (R2 0.64 to 0.82), but the other three axes had a less straightforward explanation and lower mapping performance (R2 −0.09 to 0.53). Plant community clusters were predicted most accurately in the sites with clear string‐flark topography but less accurately in the flatter site (R2 0.16–0.82). The most important remote sensing features differed between dependent variables and study sites: different topographic, spectral and textural features; and coarse‐scale and fine‐scale datasets were the most important in different tasks. We suggest that multiple different mapping approaches should be tested and several remote sensing datasets used when maps of vegetation are produced.
Study on the Movements of Organometallic Halide Perovskite Crystals on their Films
Authors: Song Tingyu , Bi Huan , Wei Qi , Yan Su , Wang Shiwei 
Published: December 2019

AbstractRecently, organometallic halide perovskites (OMHPs) have attracted significant attention due to their high light absorption coefficient, high charge carrier mobility, and long carrier lifetime. One of the key shortcomings of the OMHP device application is its poor stability under humid conditions. Thus, it is important to study the relationship between humidity and OMHP crystals in their thin films. In this work, the large‐scale movement behavior of CH3NH3PbI3‐xClx crystals in their films is discovered. It is concluded that the number of moving CH3NH3PbI3‐xClx crystals can be controlled by the humidity of the external environment. The movement behavior of the perovskite grains is attributed to the asymmetric decomposition of perovskite under high relative humidity (RH) conditions.
How does family support facilitate job satisfaction? Investigating the chain mediating effects of work–family enrichment and job‐related well‐being
Authors: Chan Xi Wen , Kalliath Parveen , Chan Christopher , Kalliath Thomas 
Published: December 2019

AbstractWhile a direct relationship between family support and job satisfaction has received empirical support, few work–family studies have examined how family support leads to job satisfaction. Drawing on the work–home resources model, we investigate the chain mediating roles of work‐to‐family enrichment (WFE), family‐to‐work enrichment (FWE), and job‐related well‐being on the relationship between family support and job satisfaction. Based on data collected from 439 social workers across Australia, structural equation modeling results revealed that the chain mediating effects of WFE and job‐related well‐being were supported. Our findings emphasize the important combination of work–family enrichment and job‐related well‐being in helping employees to harness support from their family members to achieve job satisfaction. We discuss both the theoretical and practical implications of the WFE, FWE, and job‐related well‐being mechanisms underlying the family support–job satisfaction relationship.
The Regulatory Functionality of Exosomes Derived from hUMSCs in 3D Culture for Alzheimer's Disease Therapy
Authors: Yang Lingyan , Zhai Yuanxin , Hao Ying , Zhu Zhanchi , Cheng Guosheng 
Published: December 2019

AbstractReducing amyloid‐β (Aβ) accumulation could be a potential therapeutic approach for Alzheimer's disease (AD). Particular functional biomolecules in exosomes vested by the microenvironment in which the original cells resided can be transferred to recipient cells to improve pathological conditions. However, there are few reports addressing whether exosomes derived from cells cultured on scaffolds with varying dimension can reduce Aβ deposition or ameliorate cognitive decline for AD therapy. Herein, both 3D graphene scaffold and 2D graphene film are used as the matrix for human umbilical cord mesenchymal stem cell culture, from which the supernatants are obtained to isolate exosomes. The levels of 195 kinds of miRNAs and proteins, including neprilysin, insulin‐degrading enzyme and heat shock protein 70, in 3D‐cultured exosomes (3D‐Exo) are dramatically different from those obtained from 2D culture. Hence, 3D‐Exo could up‐regulate the expression of α‐secretase and down‐regulate the β‐secretase to reduce Aβ production in both AD pathology cells and transgenic mice, through their special cargo. With rescuing Aβ pathology, 3D‐Exo exerts enhanced therapeutic effects on ameliorating the memory and cognitive deficits in AD mice. These findings provide a novel clinical application for scaffold materials and functional exosomes derived from stem cells.
Regulation of rhythmic behaviors by astrocytes
Authors: Jackson F. Rob , You Samantha , Crowe Lauren B. 
Published: December 2019

AbstractGlial astrocytes of vertebrates and invertebrates are important modulators of nervous system development, physiology, and behavior. In all species examined, astrocytes of the adult brain contain conserved circadian clocks, and multiple studies have shown that these glial cells participate in the regulation of circadian behavior and sleep. This short review summarizes recent work, using fruit fly (Drosophila) and mouse models, that document participation of astrocytes and their endogenous circadian clocks in the control of rhythmic behavior.This article is categorized under:
Gene Expression and Transcriptional Hierarchies > Regulatory Mechanisms
Nervous System Development > Flies
Statistical post‐processing of turbulence‐resolving weather forecasts for offshore wind power forecasting
Authors: Gilbert Ciaran , Messner Jakob W. , Pinson Pierre , Trombe Pierre‐Julien , Verzijlbergh Remco , van Dorp Pim , Jonker Harmen 
Published: December 2019

AbstractAccurate short‐term power forecasts are crucial for the reliable and efficient integration of wind energy in power systems and electricity markets. Typically, forecasts for hours to days ahead are based on the output of numerical weather prediction models, and with the advance of computing power, the spatial and temporal resolutions of these models have increased substantially. However, high‐resolution forecasts often exhibit spatial and/or temporal displacement errors, and when regarding typical average performance metrics, they often perform worse than smoother forecasts from lower‐resolution models. Recent computational advances have enabled the use of large‐eddy simulations (LESs) in the context of operational weather forecasting, yielding turbulence‐resolving weather forecasts with a spatial resolution of 100 m or finer and a temporal resolution of 30 seconds or less. This paper is a proof‐of‐concept study on the prospect of leveraging these ultra high‐resolution weather models for operational forecasting at Horns Rev I in Denmark. It is shown that temporal smoothing of the forecasts clearly improves their skill, even for the benchmark resolution forecast, although potentially valuable high‐frequency information is lost. Therefore, a statistical post‐processing approach is explored on the basis of smoothing and feature engineering from the high‐frequency signal. The results indicate that for wind farm forecasting, using information content from both the standard and LES resolution models improves the forecast accuracy, especially with a feature selection stage, compared with using the information content solely from either source.
On the Frequency and Severity of Interstate Wars
Authors: Clauset Aaron 
Published: December 2019

AbstractLewis Fry Richardson argued that the frequency and severity of deadly conflicts of all kinds, from homicides to interstate wars and everything in between, followed universal statistical patterns: their frequency followed a simple Poisson arrival process and their severity followed a simple power-law distribution. Although his methods and data in the mid-20th century were neither rigorous nor comprehensive, his insights about violent conflicts have endured. In this chapter, using modern statistical methods and data, I show that Richardson’s original claims are largely correct, with a few caveats. These facts place important constraints on our understanding of the underlying mechanisms that produce individual wars and periods of peace and shed light on the persistent debate about trends in conflict.
The Decline of War Since 1950: New Evidence
Authors: Spagat Michael , van Weezel Stijn 
Published: December 2019

AbstractFor the past 70 years, there has been a downward trend in war sizes, but the idea of an enduring ‘long peace’ remains controversial. Some recent contributions suggest that observed war patterns, including the long peace, could have resulted from a long-standing and unchanging war-generating process, an idea rooted in Lewis F Richardson’s pioneering work on war. Focusing on the hypothesis that the war sizes after the Second World War are generated by the same mechanism that generated war sizes before the Second World War, recent work failed to reject this ‘no-change’ hypothesis. In this chapter, we transform the war-size data into units of battle deaths per 100,000 of world population rather than absolute battle deaths – units appropriate for investigating the probability that a random person will die in a war. This change tilts the evidence towards rejecting no-change hypotheses. We also show that sliding the candidate break point slightly forward in time, to 1950 rather than 1945, leads us further down the path toward formal rejection of a large number of no-change hypotheses. We expand the range of wars considered to include not just inter-state wars, as is commonly done, but also intra-state wars. Now we do formally reject many versions of the no-change hypothesis. Finally, we show that our results do not depend on the choice of war dataset.
On the Equality of Bajraktarević Means to Quasi-Arithmetic Means
Authors: Páles Zsolt , Zakaria Amr 
Published: December 2019

AbstractThis paper offers a solution of the functional equation$$\begin{aligned}&\big (tf(x)+(1-t)f(y)\big )\varphi (tx+(1-t)y)\\&\quad =tf(x)\varphi (x)+(1-t)f(y)\varphi (y) \qquad (x,y\in I), \end{aligned}$$(tf(x)+(1-t)f(y))φ(tx+(1-t)y)=tf(x)φ(x)+(1-t)f(y)φ(y)(x,y∈I),where$$t\in \,]0,1[\,$$t∈]0,1[,$$\varphi :I\rightarrow \mathbb {R}$$φ:I→Ris strictly monotone, and$$f:I\rightarrow \mathbb {R}$$f:I→Ris an arbitrary unknown function. As an immediate application, we shed new light on the equality problem of Bajraktarević means with quasi-arithmetic means.
A stabilized finite element method for inverse problems subject to the convection–diffusion equation. I: diffusion-dominated regime
Authors: Burman Erik , Nechita Mihai , Oksanen Lauri 
Published: December 2019

AbstractThe numerical approximation of an inverse problem subject to the convection–diffusion equation when diffusion dominates is studied. We derive Carleman estimates that are of a form suitable for use in numerical analysis and with explicit dependence on the Péclet number. A stabilized finite element method is then proposed and analysed. An upper bound on the condition number is first derived. Combining the stability estimates on the continuous problem with the numerical stability of the method, we then obtain error estimates in local $$H^1$$H1- or $$L^2$$L2-norms that are optimal with respect to the approximation order, the problem’s stability and perturbations in data. The convergence order is the same for both norms, but the $$H^1$$H1-estimate requires an additional divergence assumption for the convective field. The theory is illustrated in some computational examples.
Outcome of primary deltoid ligament repair in acute ankle fractures: a meta-analysis of comparative studies
Authors: Salameh Motasem , Alhammoud Abduljabbar , Alkhatib Nedal , Attia Ahmed K. , Mekhaimar Mohamed M. , D’Hooghe Pieter , Mahmoud Karim 
Published: December 2019

Abstract
Purpose
The indications of deltoid ligament repair in ankle injuries with widened medial clear space in the absence of medial malleolus fracture remain controversial. Many authors reported no difference in long-term functional outcomes, while others stated that persistent medial clear space widening and malreduction are higher when deltoid ligaments went without repair. This meta-analysis aims to report the current published evidence about the outcomes of deltoid ligament repair in ankle fractures.

Methods
Several databases were searched through May 2018 for comparative studies. The primary outcome was the medial clear space correction, while secondary outcomes included maintenance of medial clear space reduction, pain scores, functional outcome, and total complications if any. Three comparative studies met the inclusion criteria for the meta-analysis. The analysis included a total of 192 patients, 81 in the deltoid ligament repair group and 111 in the non-repair group.

Results
The medial clear space correction and maintenance of the said correction on final follow-up radiographs were superior in the deltoid ligament repair group. Although the pain scores were better in the repair group at the final follow-up, this did not result in a better functional outcome, with similar total complication rates.

Conclusion
In conclusion, those who had their deltoid ligament repaired had superior early and late radiological correction of the medial clear space, an indicator of the quality of ankle reduction with better pain scores. However, no differences in the functional outcome and complications rate were reported.
Patient Experience and Outcomes of the Locally Organized ApriDec Medical Outreach Group
Authors: Katz Micah G. , Tabiri Stephen , Gyedu Adam , Price Raymond R. , Abantanga Francis A. 
Published: December 2019

AbstractBackgroundAccess to safe and effective surgery is limited in low and middle‐income countries. Short‐term surgical missions are a common platform to provide care, but the few published outcomes suggest unacceptable morbidity and mortality. We sought to study the safety and effectiveness of the ApriDec Medical Outreach Group (AMOG).MethodsData from the December 2017 and April 2018 outreaches were prospectively collected. Patient demographics, characteristics of surgery, complications of surgery, and patient quality of life were collected preoperatively and on postoperative days 15 and 30. Data were analyzed to determine complication rates and trends in quality of life.Results260/278 (93.5%) of patients completed a 30‐day follow‐up. Of these, surgical site infection was the most common complication (8.0%), followed by hematoma (4.1%). Rates of urinary tract infection were 1.2% while all other complications occurred in less than 1% of patients. There were no mortalities. With increasing time after surgery (0 to 15 days to 30 days), there was a significant improvement across each of the dimensions of quality of life (p < 0.001). All patients reported satisfaction with their procedure.ConclusionThis study demonstrated that the care provided by AMOG group to the underserved populations of northern Ghana, yielded complication rates similar to others in low‐resourced communities, leading to improved quality of life.