bluuebunny/crossref_metadata_2025_split huggingface dataset:
Untethered firing fields and intermittent silences: Why grid‐cell discharge is so variable
Authors: Nagele Johannes , Herz Andreas V.M. , Stemmler Martin B. 
Published: February 2020

AbstractGrid cells in medial entorhinal cortex are notoriously variable in their responses, despite the striking hexagonal arrangement of their spatial firing fields. Indeed, when the animal moves through a firing field, grid cells often fire much more vigorously than predicted or do not fire at all. The source of this trial‐to‐trial variability is not completely understood. By analyzing grid‐cell spike trains from mice running in open arenas and on linear tracks, we characterize the phenomenon of “missed” firing fields using the statistical theory of zero inflation. We find that one major cause of grid‐cell variability lies in the spatial representation itself: firing fields are not as strongly anchored to spatial location as the averaged grid suggests. In addition, grid fields from different cells drift together from trial to trial, regardless of whether the environment is real or virtual, or whether the animal moves in light or darkness. Spatial realignment across trials sharpens the grid representation, yielding firing fields that are more pronounced and significantly narrower. These findings indicate that ensembles of grid cells encode relative position more reliably than absolute position.
The effect of CEO incentives on deviations from institutional norms in foreign market expansion decisions: Behavioral agency and cross‐border acquisitions
Authors: Benischke Mirko H. , Martin Geoffrey P. , Gomez‐Mejia Luis R. , Ljubownikow Grigorij 
Published: February 2020

AbstractCEO incentives have been the subject of great interest for human resource scholars. We explore the institutional context within which the CEO makes sense of their incentives. Our theory suggests that CEO equity incentives interact with institutional norms to influence foreign market entry choices. Specifically, we argue that CEOs will weigh the risk bearing created by equity incentives, along with the consequences of legitimacy loss, when deciding whether to deviate from institutional norms when internationalizing. In doing so, we advance human resource literature by demonstrating that CEO responses to incentives are influenced by institutional norms and that CEOs' decisions to deviate from institutional norms are shaped by their incentives. We find support for our framework in the analysis of the stake taken by acquirers in 4,184 cross‐border acquisitions.
m6A RNA methylation regulators contribute to malignant progression in rectal cancer
Authors: Zhuang Jinfu , Lin Chunlin , Ye Jianxin 
Published: February 2020

AbstractN6,2′‐O‐dimethyladenosine (m6A) RNA methylation, which is correlated with cancer initiation and progression, is dynamically regulated by m6A RNA methylation regulators, including writers, erasers, and readers. Two subgroups of rectal cancer, including cluster1 and cluster2, were identified based on consensus clustering to m6A RNA methylation regulators. A protein–protein interaction network was constructed and hub genes were identified. The results demonstrated that the expression of WTAP was significantly associated with YTHDC1 and YTHDF2. The principal component analysis was used to compare the transcriptional profile between cluster1 and cluster2 subgroups. By using two identified m6A RNA methylation regulators, we constructed a risk signature to predict the survival outcomes of rectal cancer. The results revealed that YTHDC2 and YTHDF2 were protective genes with HR < 1. The coefficients obtained from the least absolute shrinkage and selection operator algorithm were used to calculate the risk score. Patients were then divided into low‐ and high‐risk groups based on the median risk score. The survival analysis demonstrated that there were significant differences in overall survival between these two groups (p < .05). The results of the univariate analysis showed that the risk score, AJCC stage, M stage, and age were associated with overall survival. The results of the multivariate Cox regression analysis showed that the risk score and age were still significantly associated with the overall survival (p < .05). To conclude, m6A RNA methylation regulators can be regarded as potentially useful biomarkers for predicting the prognosis and designing a treatment strategy in rectal cancer.
Long‐term effects of grazing management and buffer strips on phosphorus runoff from pastures fertilized with poultry litter
Authors: Anderson Kelsey R. , Moore Philip A. , Pilon Cristiane , Martin Jerry W. , Pote Dan. H. , Owens Phillip R. , Ashworth Amanda J. , Miller David M. , DeLaune Paul B. 
Published: February 2020

AbstractPhosphorus (P) runoff from pastures can cause accelerated eutrophication of surface waters. However, few long‐term studies have been conducted on the effects of best management practices, such as rotational grazing and/or buffer strips on P losses from pastures. The objective of this study was to evaluate the long‐term effects of grazing management and buffer strips on P runoff from pastures receiving annual (5.6 Mg ha−1) poultry litter applications. A 14‐yr study was conducted on 15 small watersheds (0.14 ha) with five treatments: hayed (H), continuously grazed (CG), rotationally grazed (R), rotationally grazed with an unfertilized buffer strip (RB), and rotationally grazed with an unfertilized fenced riparian buffer (RBR). Runoff samples were collected using automatic samplers during runoff events. Average annual runoff volumes from H (40 mm yr−1) and RBR (48 mm yr−1) were lower than CG and RB, which were both 65 mm yr−1, and from R (67 mm yr−1). Rotational grazing alone did not reduce P loads compared with continuous grazing (1.88 and 1.71 kg P ha−1 for R and CG, respectively). However, compared with CG, total P losses from RB pastures were reduced 36% with unfertilized buffer strips (1.21 kg P ha−1), 60% in RBR watersheds with unfertilized fenced riparian buffer strips (0.74 kg P ha−1), and 49% by converting pastures to hayfields (0.97 kg P ha−1). Hence, the use of unfertilized buffer strips, unfertilized fenced riparian buffer strips, or converting pastures to hayfields are effective best management practices for reducing P runoff in U.S. pasture systems.
Dynamics of rainfall extremes over India: A new perspective
Authors: Sooraj KP , Terray Pascal , Shilin Anokha , Mujumdar Milind 
Published: February 2020

AbstractA comprehensive analysis of the role of Indo‐Pakistan arid region (IPAR) in modulating the boreal summer heavy extreme rainfall events over monsoon core zone (MCZ over Indian subcontinent) at subseasonal to daily time scales is presented. The objective is to bring new perspectives on the dynamics of such rainfall extremes. Time‐lagged composite analysis shows the clustering of Monsoon Intra‐Seasonal Oscillation with monsoon rainfall daily extremes. However, our results additionally bring out the distinct role of surface thermal forcing and moist processes over IPAR as another potential and significant precursor, 16–10 days in advance, causing monsoon rainfall daily extremes over MCZ. Further analysis reveals that the warming over IPAR is initially found in the northern part of the domain, 20–15 days before the rainfall events over MCZ and is triggered by subtropical‐midlatitude interactions characterized by the intrusion of a midlatitude (i.e., Eurasian) atmospheric wave train into the Asian domain. Our analysis further reveals strong moist static energy (MSE) build‐up over the IPAR 12 days in advance, which is initially dominated by anomalous warming in the lower atmosphere, but with an incremental contribution of low‐level specific humidity as we moved forward in time towards the rainfall event. Hydrodynamic‐longwave radiative teleconnections are the primary mechanism for the persistence of the surface warming and MSE buildup over IPAR after the initial intrusion of the Eurasian wave train. The persistent warming over IPAR reinforces the land‐sea contrast between the Middle East and western equatorial Indian Ocean to its south, and this subsequently leads to pressure anomalies and monsoon circulation changes through geostrophic wind adjustment, thus enhancing westerlies over Arabian Sea. All these factors lead to the development of a gigantic monsoon trough over central India thus causing the rainfall extremes over MCZ through the genesis of synoptic vortices.
Standoff Raman spectroscopy for future Europa Lander missions
Authors: Sharma S.K. , Porter J.N. , Misra A.K. , Acosta‐Maeda T.E. , Angel S.M. , McKay C.P. 
Published: February 2020

AbstractNear Infrared Mapping Spectrograph data from the Galileo spacecraft and cryogenic laboratory reflectance measurements on hydrated compounds identified the presence of mixtures of hydrous magnesium sulfate, sulfuric acid, and hydrogen peroxide on the surface of Europa. Standoff Raman spectroscopy is ideally suited for exploring terrestrial Europa analog sites and Europa because of its ability to unambiguously identify minerals, organic compounds, and biomarkers inside ice. In the present work, we evaluated the performance of a standoff Raman system at various distances by measuring Raman spectra of hydrogen peroxide, sulfuric acid, and hydrous sulfate minerals, which are predicted to be present on Europa's surface. To simulate Europa's surface environment, Raman spectra of MgSO4·7H2O, FeSO4·7H2O, gypsum (CaSO4·2H2O), dry ice (CO2‐ice), and polycyclic aromatic hydrocarbons (PAHs) naphthalene and anthracene inside crushed H2O‐ice, shaved H2O‐ice, and a clear H2O‐ice block have also been measured. The PAHs were selected in this study because of their presence in the interstellar medium, comets, and meteorites. The results show that it will be possible to map out the non‐ice components on the surface and subsurface of Europa analog sites and Europa up to a distance of 120 m from a static lander and to a depth of ~10 cm inside ice.We have evaluated the performance of a standoff Raman system at various distances by measuring Raman spectra of hydrogen peroxide, sulfuric acid, and hydrous sulfate minerals, which are predicted to be present on Europas surface. To simulate Europas surface environment, Raman spectra of MgSO4·7H2O, FeSO4·7H2O, gypsum (CaSO4·2H2O), dry ice (CO2‐ice), and polycyclic aromatic hydrocarbons (PAHs) naphthalene and anthracene inside crushed H2O‐ice, shaved H2O‐ice, and H2O‐ice block have been measured.
Simultaneous extraction and purification of fucoxanthin from Tisochrysis lutea microalgae using compressed fluids
Authors: Gallego Rocío , Tardif Charles , Parreira Celina , Guerra Tiago , Alves Maria João , Ibáñez Elena , Herrero Miguel 
Published: February 2020

AbstractThe marine microalga Tisochrysis lutea, a Haptophyta with a thin cell wall and currently used mainly in aquaculture is a potential source of several bioactive compounds of interest such as carotenoids. In the present study, the simultaneous extraction and purification of fucoxanthin, the main carotenoid from T. lutea, was optimized using pressurized fluid extraction followed by in‐cell purification. An experimental design was employed to maximize carotenoids’ extraction; the experimental factors chosen were: (i) percentage of ethanol/ethyl acetate (0–100 %), (ii) temperature (40–150°C), and (iii) number of static extraction cycles (1–3). The maximum carotenoids’ recovery, mainly fucoxanthin, was obtained with pure ethyl acetate at 40°C using one extraction cycle, achieving values of 132.8 mg of carotenoids per gram of extract. Once the optimum extraction conditions were confirmed, in‐cell purification strategies using different adsorbents were developed to obtain fucoxanthin‐enriched extracts. Activated charcoal showed potential retention of chlorophylls allowing an effective purification of fucoxanthin in the obtained extracts. Chemical characterization of extracts was carried out by reversed‐phase high‐performance liquid chromatography with diode array detection. Therefore, a selective fractionation of high value compounds was achieved using the proposed green downstream platform based on the use of compressed fluids.
Knowledge hiding in a buyer‐supplier relationship: A pilot study
Authors: Butt Atif S. , Ahmad Ahmad B. , Shah Syed Hamad Hassan 
Published: February 2020

AbstractKnowledge hiding has been the topic of some research in supply chains in the last few years. These studies either identify antecedents of knowledge hiding or its negative consequences. However, studies pertaining to how knowledge hiding adversely affect buyer–supplier relationships are scant. Based on an initial pilot study comprising six semistructured with managers engaged in the process of buying and selling products and services, our results unveil three factors (lack of interpersonal trust, mutual loyalty, and limited interaction), which affect business relationship between managers of buying and supplying firms, when they hide knowledge from each other. This article concludes by discussing its initial contributions to theory. Finally, study limitations and future research direction are articulated.
Recent Advancements in Using Polymers for Intestinal Mucoadhesion and Mucopenetration
Authors: Taipaleenmäki Essi , Städler Brigitte 
Published: February 2020

AbstractOral administration of actives is the most desired form of delivery, but the formulations need to overcome a variety of barriers including the intestinal mucus. This feature article summarizes the developments from the past 2–3 years in this context focusing on polymer‐based formulations. The progress in assembling mucopenetrating nanoparticles is outlined considering coatings using noninteracting polymers as well as virus‐like particles and charge‐shifting particles. Next, polymers and their modification to enhance mucoadhesion are discussed, followed by providing examples of double‐encapsulation systems that aim to combine mucopenetration with mucoadhesion in the same formulation. Finally, a short outlook is provided highlighting a few of the most pressing challenges to address.
Habitat Associations and Co-Occurrence Patterns of Two Estuarine-Dependent Predatory Fishes
Authors: Livernois Mariah C. , Powers Sean P. , Albins Mark A. , Mareska John F. 
Published: February 2020

Abstract
Estuarine-dependent fishes experience a wide range of environmental conditions, and most species exhibit distinct associations with particular habitats. However, similar species or multiple conspecifics often overlap spatiotemporally, which can result in ecological interactions that have consequences for behaviors that can shape the structure and function of ecosystems. We used a long-term gill-net data set (2001–2015) to investigate the habitat associations and co-occurrence patterns of two estuarine-dependent predatory fishes, Red Drum Sciaenops ocellatus and Spotted Seatrout Cynoscion nebulosus, in coastal Alabama, USA. Both species were associated with similar environmental conditions, primarily low dissolved oxygen and low salinity, especially when temperature was low. However, differences emerged between the species with respect to the effects of interacting environmental variables on their habitat use patterns, which were likely driven by physiological, biological, and ecological dissimilarities between them. Concerning their biogenic habitat use, extensive submerged aquatic vegetation (SAV) was an important habitat for both species, but Spotted Seatrout appeared to prefer high-salinity SAV beds, while Red Drum associated with SAV regardless of salinity. Spotted Seatrout were associated with extensive emergent marsh edges, and the positive relationship between Red Drum and SAV was diminished when marsh edge was abundant. Co-occurrence was observed primarily in habitats with which both species were associated, most frequently in shallow, prey-rich marsh edges and high-salinity seagrass beds. These observed habitat use patterns elucidate the subtle differences in resource use that allow these species to coexist and suggest potential areas where interactions between them may shape their roles as predators.
Recovering local equilibrium from three‐dimensional compatible finite element solutions
Authors: Moitinho de Almeida J. P. , Maunder E. A. W. 
Published: February 2020

SUMMARYWe study the application to compressible and incompressible three‐dimensional elasticity problems of the technique that we proposed in 2009 for the recovery of equilibrated stresses from compatible finite element solutions. The case of finite elements with linear displacement approximations, for which the partitioned systems of loads are not initially balanced in terms of rotational equilibrium, addressed in 2012, is also considered. The article includes a presentation of the implementation details, a study of the convergence in terms of the energy of the error, and a characterization of the solutions obtained.
Plasma lipid peroxidation and antioxidant status in patients with oral precancerous lesions and oral cancer
Authors: Shahi Yadvendra , Samadi Fahad M. , Mukherjee Sayali 
Published: February 2020

AbstractObjectiveOral precancerous lesions like oral leukoplakia and oral submucosal fibrosis are very common in north Indian population which often leads to oral squamous cell carcinoma. Chewing of tobacco, pan masala, and betel nut is very common among north Indian women. Reactive oxygen species (ROS) generation is an important outcome of this habit. Imbalance between ROS and antioxidants leads to oxidative stress. The aim of our study was to determine the level of antioxidants in oral precancerous lesions and oral cancer to predict disease susceptibility.MethodThe study group consisted of 120 subjects among which 25 were with histopathologically confirmed oral cancer, 50 with histopathologically confirmed oral precancerous lesions, and 45 were healthy controls. Blood samples were collected for the evaluation of reduced glutathione (GSH) and antioxidant enzymes, catalase, superoxide dismutase (SOD), glutathione reductase (GR) and oxidative stress markers like malondialdehyde (MDA) and nitrite.ResultResults demonstrated a decrease in antioxidant enzymes such as catalase, SOD, and GR in oral precancerous lesion and oral cancer from that of healthy control. An increase in reduced glutathione concentration was observed in oral precancerous lesion and oral cancer as compared to healthy control. Malondialdehyde level was increased significantly in oral cancer. Increase in nitrite concentration was not statistically significant in oral precancerous lesion and oral cancer patients as compared to control.ConclusionOxidative stress and antioxidants have been found to be important indicators in oral cancer and in pre‐malignant lesions which may predict susceptibility of development of oral cancer.
Mechanical properties of electrospun nanofiber reinforced/interleaved epoxy matrix composites—A review
Authors: Shakil Usaid A. , Hassan Shukur B. A. , Yahya Mohd Y. , Nauman Saad 
Published: February 2020

AbstractElectrospinning has by far proved to be the most successful method to spin high aspect and surface area to volume ratio nanofiber for multidisciplinary applications. Its application, however, as reinforcement in fiber reinforced polymer matrix composites (FRPC's) started from interlaminar fracture toughness improvement through interleaving. Since then, its usage both in short fiber and nonwoven mat formation has been phenomenally increased to tailor mechanical properties. This review paper focuses on application of nanofiber in multiscale reinforced epoxy matrix composites for mechanical performance. After a brief overview of electrospinning and spinning parameters, it presents a case for nanofiber as reinforcement with attendant mechanisms to develop insight into nanocomposite performance. Next, it summarizes and shares findings of studies, carried out in last 10 years, seeking to enhance tensile, flexural, interlaminar toughness, impact, and fatigue properties of epoxy composites through electrospun nanofiber reinforcement. Finally, it presents a perspective to gain headways in nanofiber reinforced FRPC's research through a variety of processing and material variables.
Fluorescent reporters for functional analysis in rice leaves
Authors: Luginbuehl Leonie H. , El‐Sharnouby Sherif , Wang Na , Hibberd Julian M. 
Published: February 2020

AbstractFluorescent reporters have facilitated non‐invasive imaging in multiple plant species and thus allowed the analysis of processes ranging from gene expression and protein localization to cellular patterning. However, in rice, a globally important crop and model species, there are relatively few reports of fluorescent proteins being used in leaves. Fluorescence imaging is particularly difficult in the rice leaf blade, likely due to a high degree of light scattering in this tissue. To address this, we investigated approaches to improve deep imaging in mature rice leaf blades. We found that ClearSee treatment, which has previously been used to visualize fluorescent reporters in whole tissues of plants, led to improved imaging in rice. Removing epidermal and subtending mesophyll cell layers was faster than ClearSee and also reduced light scattering such that imaging of fluorescent proteins in deeper leaf layers was possible. To expand the range of fluorescent proteins suitable for imaging in rice, we screened twelve whose spectral profiles spanned most of the visible spectrum. This identified five proteins (mTurquoise2, mNeonGreen, mClover3, mKOκ, and tdTomato) that are robustly expressed and detectable in mesophyll cells of stably transformed plants. Using microparticle bombardment, we show that mTurquoise2 and mNeonGreen can be used for simultaneous multicolor imaging of different subcellular compartments. Overall, we conclude that mTurquoise2, mNeonGreen, mClover3, mKOκ, and tdTomato are suitable for high‐resolution live imaging of rice leaves, both after transient and stable transformation. Along with the rapid microparticle bombardment method, which allows transient transformation of major cell types in the leaf blade, these fluorescent reporters should greatly facilitate the analysis of gene expression and cell biology in rice.
Delay compensated control of the Stefan problem and robustness to delay mismatch
Authors: Koga Shumon , Bresch‐Pietri Delphine , Krstic Miroslav 
Published: February 2020

SummaryThis paper presents a control design for the one‐phase Stefan problem under actuator delay via a backstepping method. The Stefan problem represents a liquid‐solid phase change phenomenon which describes the time evolution of a material's temperature profile and the interface position. The actuator delay is modeled by a first‐order hyperbolic partial differential equation (PDE), resulting in a cascaded transport‐diffusion PDE system defined on a time‐varying spatial domain described by an ordinary differential equation (ODE). Two nonlinear backstepping transformations are utilized for the control design. The setpoint restriction is given to guarantee a physical constraint on the proposed controller for the melting process. This constraint ensures the exponential convergence of the moving interface to a setpoint and the exponential stability of the temperature equilibrium profile and the delayed controller in the norm. Furthermore, robustness analysis with respect to the delay mismatch between the plant and the controller is studied, which provides analogous results to the exact compensation by restricting the control gain.