bluuebunny/crossref_metadata_2025_split huggingface dataset:
About water degumming and the hydration of non‐hydratable phosphatides
Authors: Dijkstra Albert J. 
Published: April 2017

Although we have been degumming and neutralizing oils for over a century, we still do not know the mechanisms of these reactions in detail. The present “Hypothesis Paper” reviews a number of outstanding questions, raises a number of further questions but also provides some answers. The main outstanding question concerns the hydration of phosphatides during water degumming: is this thermodynamically or kinetically controlled? Crucial experiments show it to be controlled by the thermodynamically determined partition coefficients. One of the further questions concerns the compounds present in oil that contain phosphorus but differ from the known phosphatides. One of the suggested answers concerns the “charge balance” of the water degumming process. By assuming that the phosphatidic acid that is removed during water degumming is removed as its potassium salt and that the calcium that is removed is removed as calcium soap, the positive and negative charges involved in the water degumming process can be made to balance. The paper also confirms that complete removal of phosphatides requires a really strong and concentrated basePractical applications: Almost all oil produced worldwide is either degummed or neutralized or both. Gaining insight in the chemistry involved must surely lead to practical applications and savings which, given the scale of operation, will be quite substantial.Crude oil contains various phosphatides that are removed during the degumming and the refining processes. It has now been found that this removal is thermodynamically controlled rather than kinetically as reported in the literature. The removal of non‐hydratable phosphatides on prolonged exposure to water has been found to be by autocatalytic hydrolysis. It has also been found that by assuming that the calcium that is removed during water degumming leaves the oil as calcium soaps, the positive and negative molecules that disappear on degumming are in balance. Even so, the question by what mechanism the non‐hydratable phosphatides are removed during alkali refining still has to be resolved.
Dendrogeomorphic chronologies of landslides: Dating of true slide movements?
Authors: Šilhán Karel 
Published: April 2017

AbstractDendrogeomorphic chronologies of landslide movements are frequently used to investigate past landslide activity. Slide areas are often affected by other slope movements (e.g. creep) simultaneously. Trees growing on landslides record all types of ground movements, which potentially creates significant noise in tree ring based chronologies of landslide movements. The effect of creep movements on dendrogeomorphic landslide chronologies was evaluated in a block‐type landslide in the south‐western foreland of the Orlické hory Mountains. In total, 272 trees (Picea abies and Fagus sylvatica) were sampled (1088 increment cores) on the sub‐horizontal surfaces of rotated slide blocks, which were presumably created only by slide movements, and on the steep internal scarps separating landslide blocks, which were presumably created and affected by a combination of slide and creep movements. Ground movements were dated based on growth disturbances identified in an analysis of eccentric tree growth.The trees growing on the internal landslide scarps separating the rotated blocks exhibited a significantly higher number and frequency of growth disturbances than those growing on the sub‐horizontal block surfaces. All eight dated block surface movements were also identified on the internal scarps. Creep‐based events represented as many as 70% of the dated movement events on the internal scarps. Varying the It thresholds did not filter out more than 40% of the noise without significantly reducing the number of true dated slide events. A significant difference was observed between the ability of P. abies and F. sylvatica to record ground movements by eccentric growth. Probably due to its shallower roots (and weaker anchoring of the tree to landslide blocks), P. abies appears to be more sensitive to surficial ground movement, which potentially increases the proportion of dated creep events (noise). Thus, the careful selection of sampled tree species with different physiologies should be considered during dendrogeomorphic field sampling. Copyright © 2017 John Wiley & Sons, Ltd.
Moving immersed boundary method
Authors: Cai Shang‐Gui , Ouahsine Abdellatif , Favier Julien , Hoarau Yannick 
Published: April 2017

SummaryA novel implicit immersed boundary method of high accuracy and efficiency is presented for the simulation of incompressible viscous flow over complex stationary or moving solid boundaries. A boundary force is often introduced in many immersed boundary methods to mimic the presence of solid boundary, such that the overall simulation can be performed on a simple Cartesian grid. The current method inherits this idea and considers the boundary force as a Lagrange multiplier to enforce the no‐slip constraint at the solid boundary, instead of applying constitutional relations for rigid bodies. Hence excessive constraint on the time step is circumvented, and the time step only depends on the discretization of fluid Navier‐Stokes equations, like the CFL condition in present work. To determine the boundary force, an additional moving force equation is derived. The dimension of this derived system is proportional to the number of Lagrangian points describing the solid boundaries, which makes the method very suitable for moving boundary problems since the time for matrix update and system solving is not significant. The force coefficient matrix is made symmetric and positive definite so that the conjugate gradient method can solve the system quickly. The proposed immersed boundary method is incorporated into the fluid solver with a second‐order accurate projection method as a plug‐in. The overall scheme is handled under an efficient fractional step framework, namely, prediction, forcing, and projection. Various simulations are performed to validate current method, and the results compare well with previous experimental and numerical studies.
A dissipation‐free numerical method to solve one‐dimensional hyperbolic flow equations
Authors: Cao Zhiwei , Liu Zhifeng , Wang Xiaohong , Shi Anfeng , Luo Haishan , Noetinger Benoît 
Published: April 2017

SummaryIn this paper, a numerical method to capture the shock wave propagation in 1‐dimensional fluid flow problems with 0 numerical dissipation is presented. Instead of using a traditional discrete grid, the new numerical method is built on a range‐discrete grid, which is obtained by a direct subdivision of values around the shock area. The range discrete grid consists of 2 types: continuous points and shock points. Numerical solution is achieved by tracking characteristics and shocks for the movements of continuous and shock points, respectively. Shocks can be generated or eliminated when triggering entropy conditions in a marking step. The method is conservative and total variation diminishing. We apply this new method to several examples, including solving Burgers equation for aerodynamics, Buckley‐Leverett equation for fractional flow in porous media, and the classical traffic flow. The solutions were verified against analytical solutions under simple conditions. Comparisons with several other traditional methods showed that the new method achieves a higher accuracy in capturing the shock while using much less grid number. The new method can serve as a fast tool to assess the shock wave propagation in various flow problems with good accuracy.
Evaluating the hydrological and hydrochemical responses of a High Arctic catchment during an exceptionally warm summer
Authors: Lamhonwah Daniel , Lafrenière Melissa J. , Lamoureux Scott F. , Wolfe Brent B. 
Published: April 2017

AbstractThe Arctic has experienced substantial warming during the past century with models projecting continued warming accompanied by increases in summer precipitation for most regions. A key impact of increasing air surface temperatures is the deepening of the active layer, which is expected to alter hydrological processes and pathways. The aim of this study was to determine how one of the warmest and wettest summers in the past decade at a High Arctic watershed impacted water infiltration and storage in deeply thawed soil and solute concentrations in stream runoff during the thaw period. In June and July 2012 at the Cape Bounty Watershed Observatory, we combined active layer measurements with major ion concentrations and stable isotopes in surface waters to characterize the movement of different runoff sources: snowmelt, rainfall, and soil water. Results indicate that deep ground thaw enhanced the storage of infiltrated water following rainfall. Soil water from infiltrated rainfall flowed through the thawed transient layer and upper permafrost, which likely solubilized ions previously stored at depth. Subsequent rainfall events acted as a hydrological flushing mechanism, mobilizing solutes from the subsurface to the surface. This solute flushing substantially increased ion concentrations in stream runoff throughout mid to late July. Results further suggest the importance of rainfall and soil water as sources of runoff in a High Arctic catchment during mid to late summer as infiltrated snowmelt is drained from soil following baseflow. Although there was some evaporation of surface water, our study indicates that flushing from solute stores in the transient layer was the primary driver of increased ion concentrations in stream runoff and not evaporative concentration of surface water. With warmer and wetter summers projected for the Arctic, ion concentrations in runoff (especially in the late thaw season), will likely increase due to the deep storage and subsurface flow of infiltrated water and subsequent flushing of previously frozen solutes to the surface.
Impact of shared care program in follow‐up of childhood cancer survivors: An intervention study
Authors: Ducassou Stéphane , Chipi Maïté , Pouyade Aurélie , Afonso Mélanie , Demeaux Jean‐Louis , Ducos Gérard , Pérel Yves , Ansoborlo Sophie 
Published: April 2017

AbstractBackgroundWith the growing rate of childhood cancer cure and the risks of sequelae, long‐term follow‐up (FU) of survivors is a central issue. Several models have been proven far from satisfactory. Shared care FU is the result of collaboration between general practitioners (GPs) and cancer centers. We sought to demonstrate the feasibility of setting up a shared care program based on the patient‐centered education of GPs and to evaluate the impact of this model in an intervention study.MethodsWe compared the FU care achievement in two childhood cancer survivor cohorts in the same pediatric oncology center, (i) control group (n = 134) and (ii) intervention study cohort (n = 137), after setting up the program.ResultsThe rate of survivors answering the survey and the rate of patients involved in FU by their GPs were higher in intervention study cohort than in baseline one (132/137 vs. 72/134 and 110/132 vs. 13/72; P ≤ 0.0001). The lack of any FU was definitely lower (10/132 vs. 18/72; P = 0.001) in the intervention study cohort.ConclusionIn this shared care program, survivors overcame distrust in their GP's knowledge and entered the FU program after their GPs had been involved in patient‐centered education. Personalized and incentive‐based guidance was very useful in helping survivors to adhere to FU. Support of a dedicated long‐term FU team was very useful. A nationwide organization, consideration of special needs in subgroups of survivors and sustained funding are needed to adjust the program in the very long term.
Effectiveness of a pragmatic school‐based universal intervention targeting student resilience protective factors in reducing mental health problems in adolescents
Authors: Dray Julia , Bowman Jenny , Campbell Elizabeth , Freund Megan , Hodder Rebecca , Wolfenden Luke , Richards Jody , Leane Catherine , Green Sue , Lecathelinais Christophe , Oldmeadow Christopher , Attia John , Gillham Karen , Wiggers John 
Published: April 2017

ABSTRACTWorldwide, 10–20% of adolescents experience mental health problems. Strategies aimed at strengthening resilience protective factors provide a potential approach for reducing mental health problems in adolescents. This study evaluated the effectiveness of a universal, school‐based intervention targeting resilience protective factors in reducing mental health problems in adolescents. A cluster randomised controlled trial was conducted in 20 intervention and 12 control secondary schools located in socio‐economically disadvantaged areas of NSW, Australia. Data were collected from 3115 students at baseline (Grade 7, 2011), of whom 2149 provided data at follow up (Grade 10, 2014; enrolments in Grades 7 to 10 typically aged 12–16 years; 50% male; 69.0% retention). There were no significant differences between groups at follow‐up for three mental health outcomes: total SDQ, internalising problems, and prosocial behaviour. A small statistically significant difference in favour of the control group was found for externalising problems. Findings highlight the continued difficulties in developing effective, school‐based prevention programs for mental health problems in adolescents.Trial registrationANZCTR (Ref no: ACTRN12611000606987).
Effect of long‐term storage in biobanks on cerebrospinal fluid biomarker Aβ1‐42, T‐tau, and P‐tau values
Authors: Willemse Eline A.J. , van Uffelen Kees W.J. , van der Flier Wiesje M. , Teunissen Charlotte E. 
Published: April 2017

AbstractIntroductionWe studied the effect of long‐term storage at −80°C on cerebrospinal fluid (CSF) biomarker levels. Our approach assumed consistency of mean biomarker levels in a homogenous Alzheimer's disease patient cohort over time.MethodsWe selected 148 Alzheimer's disease samples that had inclusion dates equally distributed over the years 2001 to 2013 from our biobank. The concentrations of CSF biomarkers, amyloid β1–42 (Aβ1–42), total tau (T‐tau), and phosphorylated tau181 (P‐tau), were measured with one enzyme‐linked immunosorbent assay lot. Results were compared with historical results obtained at biobank inclusion.ResultsLinear regression analyses showed that the levels of CSF biomarkers, Aβ1–42, T‐tau, and P‐tau, were not related to storage time at −80°C (β = 0.015, 0.048, and 0.0016 pg/mL per day, not significant). However, the differences between remeasured concentrations of Aβ1–42 and concentrations at biobank inclusion measured for more than 30 assay batches increased with increasing time difference.DiscussionThe levels of CSF biomarkers, Aβ1–42, T‐tau, and P‐tau, did not significantly change during the maximum period of 12 years of storage at −80°C. Batch variation for Aβ1–42 is a factor that should be controlled for when using historical cohorts.
eTumorType, An Algorithm of Discriminating Cancer Types for Circulating Tumor Cells or Cell-Free DNAs in Blood
Authors: Zou Jinfeng , Wang Edwin 
Published: April 2017

Abstract
With the technology development on detecting circulating tumor cells (CTCs) and cell-free DNAs (cfDNAs) in blood, serum, and plasma, non-invasive diagnosis of cancer becomes promising. A few studies reported good correlations between signals from tumor tissues and CTCs or cfDNAs, making it possible to detect cancers using CTCs and cfDNAs. However, the detection cannot tell which cancer types the person has. To meet these challenges, we developed an algorithm, eTumorType, to identify cancer types based on copy number variations (CNVs) of the cancer founding clone. eTumorType integrates cancer hallmark concepts and a few computational techniques such as stochastic gradient boosting, voting, centroid, and leading patterns. eTumorType has been trained and validated on a large dataset including 18 common cancer types and 5327 tumor samples. eTumorType produced high accuracies (0.86–0.96) and high recall rates (0.79–0.92) for predicting colon, brain, prostate, and kidney cancers. In addition, relatively high accuracies (0.78–0.92) and recall rates (0.58–0.95) have also been achieved for predicting ovarian, breast luminal, lung, endometrial, stomach, head and neck, leukemia, and skin cancers. These results suggest that eTumorType could be used for non-invasive diagnosis to determine cancer types based on CNVs of CTCs and cfDNAs.
Strategies for14C Dating the Oxtotitlán Cave Paintings, Guerrero, Mexico
Authors: Russ Jon , Pohl Mary D. , von Nagy Christopher L. , Steelman Karen L. , Hurst Heather , Ashby Leonard , Schmidt Paul , Padilla Gutiérrez Eliseo F. , Rowe Marvin W. 
Published: April 2017

ABSTRACTOxtotitlán Cave paintings have been considered among the earliest in Mesoamerica on stylistic grounds, but confirmation of this hypothesis through absolute dating has not been attempted until now. We describe the application of advanced radiocarbon strategies developed for situations such as caves with high carbon backgrounds. Using a low-temperature plasma oxidation system, we dated both the ancient paint and the biogenic rock coatings that cover the paint layers at Oxtotitlán. Our research has significantly expanded the time frame for the production of polychrome rock paintings encompassing the Early Formative and Late Formative/Early Classic periods, statistically spanning a long era from before ca. 1500 cal B.C. to cal A.D. 600.
Asymptotic results for the multiple scan statistic
Authors: Boutsikas M. V. , Koutras M. V. , Milienos F. S. 
Published: April 2017

AbstractThe contribution of the theory of scan statistics to the study of many real-life applications has been rapidly expanding during the last decades. The multiple scan statistic, defined on a sequence of n Bernoulli trials, enumerates the number of occurrences of k consecutive trials which contain at least r successes among them (r≤k≤n). In this paper we establish some asymptotic results for the distribution of the multiple scan statistic, as n,k,r→∞ and illustrate their accuracy through a simulation study. Our approach is based on an appropriate combination of compound Poisson approximation and random walk theory.
On occupation times of the first and third quadrants for planar Brownian motion
Authors: Ernst Philip A. , Shepp Larry 
Published: April 2017

AbstractIn Bingham and Doney (1988) the authors presented the applied probability community with a question which is very simply stated, yet is extremely difficult to solve: what is the distribution of the quadrant occupation time of planar Brownian motion? In this paper we study an alternate formulation of this long-standing open problem: let X(t), Y(t) t≥0, be standard Brownian motions starting at x, y, respectively. Find the distribution of the total time T=Leb{t∈[0,1]: X(t)×Y(t)>0}, when x=y=0, i.e. the occupation time of the union of the first and third quadrants. If two adjacent quadrants are used, the problem becomes much easier and the distribution of T follows the arcsine law.
Local limits of Galton–Watson trees conditioned on the number of protected nodes
Authors: Abraham Romain , Bouaziz Aymen , Delmas Jean-François 
Published: April 2017

AbstractWe consider a marking procedure of the vertices of a tree where each vertex is marked independently from the others with a probability that depends only on its out-degree. We prove that a critical Galton–Watson tree conditioned on having a large number of marked vertices converges in distribution to the associated size-biased tree. We then apply this result to give the limit in distribution of a critical Galton–Watson tree conditioned on having a large number of protected nodes.
Large deviations of means of heavy-tailed random variables with finite moments of all orders
Authors: Lehtomaa Jaakko 
Published: April 2017

AbstractLogarithmic asymptotics of the mean process {Sn∕n} are investigated in the presence of heavy-tailed increments. As a consequence, a full large deviations principle for means is obtained when the hazard function of an increment is regularly varying with index α∈(0,1). This class includes all stretched exponential distributions. Thus, the previous research of Gantert et al. (2014) is extended. Furthermore, the presented proofs are more transparent than the techniques used by Nagaev (1979). In addition, the novel approach is compatible with other common classes of distributions, e.g. those of lognormal type.
Stochastic comparisons of interfailure times under a relevation replacement policy
Authors: Sordo Miguel A. , Psarrakos Georgios 
Published: April 2017

AbstractWe provide some results for the comparison of the failure times and interfailure times of two systems based on a replacement policy proposed by Kapodistria and Psarrakos (2012). In particular, we show that when the first failure times are ordered in terms of the dispersive order (or, the excess wealth order), then the successive interfailure times are ordered in terms of the usual stochastic order (respectively, the increasing convex order). As a consequence, we provide comparison results for the cumulative residual entropies of the systems and their dynamic versions.
Nonuniversality of weighted random graphs with infinite variance degree
Authors: Baroni Enrico , van der Hofstad Remco , Komjáthy Júlia 
Published: April 2017

AbstractWe prove nonuniversality results for first-passage percolation on the configuration model with independent and identically distributed (i.i.d.) degrees having infinite variance. We focus on the weight of the optimal path between two uniform vertices. Depending on the properties of the weight distribution, we use an example-based approach and show that rather different behaviours are possible. When the weights are almost surely larger than a constant, the weight and number of edges in the graph grow proportionally to log logn, as for the graph distances. On the other hand, when the continuous-time branching process describing the first-passage percolation exploration through the graph reaches infinitely many vertices in finite time, the weight converges to the sum of two i.i.d. random variables representing the explosion times of the continuous-time processes started from the two sources. This nonuniversality is in sharp contrast to the setting where the degree sequence has a finite variance, Bhamidiet al.(2012).
From coin tossing to rock-paper-scissors and beyond: a log-exp gap theorem for selecting a leader
Authors: Fuchs Michael , Hwang Hsien-Kuei , Itoh Yoshiaki 
Published: April 2017

AbstractA class of games for finding a leader among a group of candidates is studied in detail. This class covers games based on coin tossing and rock-paper-scissors as special cases and its complexity exhibits similar stochastic behaviors: either of logarithmic mean and bounded variance or of exponential mean and exponential variance. Many applications are also discussed.
Dynkin games with heterogeneous beliefs
Authors: Ekström Erik , Glover Kristoffer , Leniec Marta 
Published: April 2017

AbstractWe study zero-sum optimal stopping games (Dynkin games) between two players who disagree about the underlying model. In a Markovian setting, a verification result is established showing that if a pair of functions can be found that satisfies some natural conditions then a Nash equilibrium of stopping times is obtained, with the given functions as the corresponding value functions. In general, however, there is no uniqueness of Nash equilibria, and different equilibria give rise to different value functions. As an example, we provide a thorough study of the game version of the American call option under heterogeneous beliefs. Finally, we also study equilibria in randomized stopping times.