bluuebunny/crossref_metadata_2025 huggingface dataset:
Power Tool or Dull Blade? Selectorate Theory for Autocracies
Authors: Gallagher Mary E. , Hanson Jonathan K.
Published: March 2015

This article assesses the utility of selectorate theory as a tool for understanding authoritarian politics. We start by discussing the intellectual history of the selectorate concept and its original usage in the authoritarian context. We then turn our focus to the selectorate theory as developed in The Logic of Political Survival (LPS) ( Bueno de Mesquita et al. 2003 ), identifying three problematic aspects of the theory and its application to authoritarian politics. First, the utility of the theory's key concepts of the selectorate and winning coalition is questionable in authoritarian systems where formal institutions to structure political transitions are absent or inconsequential. Second, measurement of the sizes of the selectorate and winning coalition is flawed, calling into question the empirical findings in LPS, such as its central claims about the survival of rulers. Third, the assumptions in the LPS version of the theory are restrictive in ways that reduce the utility of the selectorate concept relative to earlier works. We conclude that selectorate theory is a blunt instrument for understanding authoritarian rule.
Statistical Foundations for Model-Based Adjustments
Authors: Greenland Sander , Pearce Neil
Published: March 2015

Most epidemiology textbooks that discuss models are vague on details of model selection. This lack of detail may be understandable since selection should be strongly influenced by features of the particular study, including contextual (prior) information about covariates that may confound, modify, or mediate the effect under study. It is thus important that authors document their modeling goals and strategies and understand the contextual interpretation of model parameters and model selection criteria. To illustrate this point, we review several established strategies for selecting model covariates, describe their shortcomings, and point to refinements, assuming that the main goal is to derive the most accurate effect estimates obtainable from the data and available resources. This goal shifts the focus to prediction of exposure or potential outcomes (or both) to adjust for confounding; it thus differs from the goal of ordinary statistical modeling, which is to passively predict outcomes. Nonetheless, methods and software for passive prediction can be used for causal inference as well, provided that the target parameters are shifted appropriately.
Regulating Chemicals: Law, Science, and the Unbearable Burdens of Regulation
Authors: Silbergeld Ellen K. , Mandrioli Daniele , Cranor Carl F.
Published: March 2015

The challenges of regulating industrial chemicals remain unresolved in the United States. The Toxic Substances Control Act (TSCA) of 1976 was the first legislation to extend coverage to the regulation of industrial chemicals, both existing and newly registered. However, decisions related to both law and science that were made in passing this law inevitably rendered it ineffectual. Attempts to fix these shortcomings have not been successful. In light of the European Union's passage of innovative principles and requirements for chemical regulation, it is no longer possible to deny the opportunity and need for reform in US law and practice.
Incorporating Both Randomized and Observational Data into a Single Analysis
Authors: Kaizar Eloise E.
Published: March 2015

Although both randomized and nonrandomized study data relevant to a question of treatment efficacy are often available and separately analyzed, these data are rarely formally combined in a single analysis. One possible reason for this is the apparent or feared disagreement of effect estimates across designs, which can be attributed both to differences in estimand definition and to analyses that may produce biased estimators. This article reviews specific models and general frameworks that aim to harmonize analyses from the two designs and combine them via a single analysis that ideally exploits the relative strengths of each design. The development of such methods is still in its infancy, and examples of applications with joint analyses are rare. This area would greatly benefit from more attention from researchers in statistical methods and applications.
Functional Regression
Authors: Morris Jeffrey S.
Published: March 2015

Functional data analysis (FDA) involves the analysis of data whose ideal units of observation are functions defined on some continuous domain, and the observed data consist of a sample of functions taken from some population, sampled on a discrete grid. Ramsay & Silverman's (1997) textbook sparked the development of this field, which has accelerated in the past 10 years to become one of the fastest growing areas of statistics, fueled by the growing number of applications yielding this type of data. One unique characteristic of FDA is the need to combine information both across and within functions, which Ramsay and Silverman called replication and regularization, respectively. This article focuses on functional regression, the area of FDA that has received the most attention in applications and methodological development. First, there is an introduction to basis functions, key building blocks for regularization in functional regression methods, followed by an overview of functional regression methods, split into three types: (a) functional predictor regression (scalar-on-function), (b) functional response regression (function-on-scalar), and (c) function-on-function regression. For each, the role of replication and regularization is discussed and the methodological development described in a roughly chronological manner, at times deviating from the historical timeline to group together similar methods. The primary focus is on modeling and methodology, highlighting the modeling structures that have been developed and the various regularization approaches employed. The review concludes with a brief discussion describing potential areas of future development in this field.
Chronic overeating impairs hepatic glucose uptake and disposition
Authors: Coate Katie C. , Kraft Guillaume , Shiota Masakazu , Smith Marta S. , Farmer Ben , Neal Doss W. , Williams Phil , Cherrington Alan D. , Moore Mary Courtney
Published: March 2015

Dogs consuming a hypercaloric high-fat and -fructose diet (52 and 17% of total energy, respectively) or a diet high in either fructose or fat for 4 wk exhibited blunted net hepatic glucose uptake (NHGU) and glycogen deposition in response to hyperinsulinemia, hyperglycemia, and portal glucose delivery. The effect of a hypercaloric diet containing neither fructose nor excessive fat has not been examined. Dogs with an initial weight of ≈25 kg consumed a chow and meat diet (31% protein, 44% carbohydrate, and 26% fat) in weight-maintaining (CTR; n = 6) or excessive (Hkcal; n = 7) amounts for 4 wk (cumulative weight gain 0.0 ± 0.3 and 1.5 ± 0.5 kg, respectively, P < 0.05). They then underwent clamp studies with infusions of somatostatin and intraportal insulin (4× basal) and glucagon (basal). The hepatic glucose load was doubled with peripheral (Pe) glucose infusion for 90 min (P1) and intraportal glucose at 4 mg·kg−1·min−1plus Pe glucose for the final 90 min (P2). NHGU was blunted ( P < 0.05) in Hkcal during both periods (mg·kg−1·min−1; P1: 1.7 ± 0.2 vs. 0.3 ± 0.4; P2: 3.6 ± 0.3 vs. 2.3 ± 0.4, CTR vs. Hkcal, respectively). Terminal hepatic glucokinase catalytic activity was reduced nearly 50% in Hkcal vs. CTR ( P < 0.05), although glucokinase protein did not differ between groups. In Hkcal vs. CTR, liver glycogen was reduced 27% ( P < 0.05), with a 91% increase in glycogen phosphorylase activity ( P < 0.05) but no significant difference in glycogen synthase activity. Thus, Hkcal impaired NHGU and glycogen synthesis compared with CTR, indicating that excessive energy intake, even if the diet is balanced and nutritious, negatively impacts hepatic glucose metabolism.
Cognitive and perceptual responses during passive heat stress in younger and older adults
Authors: Schlader Zachary J. , Gagnon Daniel , Adams Amy , Rivas Eric , Cullum C. Munro , Crandall Craig G.
Published: March 2015

We tested the hypothesis that attention, memory, and executive function are impaired to a greater extent in passively heat-stressed older adults than in passively heat-stressed younger adults. In a randomized, crossover design, 15 older (age: 69 ± 5 yr) and 14 younger (age: 30 ± 4 yr) healthy subjects underwent passive heat stress and time control trials. Cognitive tests (outcomes: accuracy and reaction time) from the CANTAB battery evaluated attention [rapid visual processing (RVP), choice reaction time (CRT)], memory [spatial span (SSP), pattern recognition memory (PRM)], and executive function [one touch stockings of Cambridge (OTS)]. Testing was undertaken on two occasions during each trial, at baseline and after internal temperature had increased by 1.0 ± 0.2°C or after a time control period. For tests that measured attention, reaction time during RVP and CRT was slower ( P ≤ 0.01) in the older group. During heat stress, RVP reaction time improved ( P < 0.01) in both groups. Heat stress had no effect ( P ≥ 0.09) on RVP or CRT accuracy in either group. For tests that measured memory, accuracy on SSP and PRM was lower ( P < 0.01) in the older group, but there was no effect of heat stress ( P ≥ 0.14). For tests that measured executive function, overall, accuracy on OTS was lower, and reaction time was slower in the older group ( P ≤ 0.05). Reaction time generally improved during heat stress, but there was no effect of heat stress on accuracy in either group. These data indicate that moderate increases in body temperature during passive heat stress do not differentially compromise cognitive function in younger and older adults.
The influence of cochlear spectral processing on the timing and amplitude of the speech-evoked auditory brain stem response
Authors: Nuttall Helen E. , Moore David R. , Barry Johanna G. , Krumbholz Katrin , de Boer Jessica
Published: March 2015

The speech-evoked auditory brain stem response (speech ABR) is widely considered to provide an index of the quality of neural temporal encoding in the central auditory pathway. The aim of the present study was to evaluate the extent to which the speech ABR is shaped by spectral processing in the cochlea. High-pass noise masking was used to record speech ABRs from delimited octave-wide frequency bands between 0.5 and 8 kHz in normal-hearing young adults. The latency of the frequency-delimited responses decreased from the lowest to the highest frequency band by up to 3.6 ms. The observed frequency-latency function was compatible with model predictions based on wave V of the click ABR. The frequency-delimited speech ABR amplitude was largest in the 2- to 4-kHz frequency band and decreased toward both higher and lower frequency bands despite the predominance of low-frequency energy in the speech stimulus. We argue that the frequency dependence of speech ABR latency and amplitude results from the decrease in cochlear filter width with decreasing frequency. The results suggest that the amplitude and latency of the speech ABR may reflect interindividual differences in cochlear, as well as central, processing. The high-pass noise-masking technique provides a useful tool for differentiating between peripheral and central effects on the speech ABR. It can be used for further elucidating the neural basis of the perceptual speech deficits that have been associated with individual differences in speech ABR characteristics.
Intrinsic excitability of human motoneurons in biceps brachii versus triceps brachii
Authors: Wilson Jessica M. , Thompson Christopher K. , Miller Laura C. , Heckman Charles J.
Published: March 2015

The intrinsic excitability of spinal motoneurons is mediated in part by the presence of persistent inward currents (PICs), which amplify synaptic input and promote self-sustained firing. Studies using animal models have shown that PICs are greater in extensor motoneurons over flexor motoneurons, but this difference has not yet been demonstrated in humans. The primary objective of this study was to determine whether a similar difference exists in humans by recording from motor units in biceps and triceps brachii during isometric contractions. We compared firing rate profiles of pairs of motor units, in which the firing rate of the lower-threshold “control” unit was used as an indicator of common drive to the higher-threshold “test” unit. The estimated contribution of the PIC was calculated as the difference in firing rate of the control unit at recruitment versus derecruitment of the test unit, a value known as the delta-F (ΔF). We found that ΔF values were significantly higher in triceps brachii (5.4 ± 0.9 imp/s) compared with biceps brachii (3.0 ± 1.4 imp/s; P < 0.001). This difference was still present even after controlling for saturation in firing rate of the control unit, rate modulation of the control unit, and differences in recruitment time between test and control units, which are known to contribute to ΔF variability. We conclude that human elbow flexor and extensor motor units exhibit differences in intrinsic excitability, contributing to different neural motor control strategies between muscle groups.
Long-range intralaminar noise correlations in the barrel cortex
Authors: Reyes-Puerta Vicente , Amitai Yael , Sun Jyh-Jang , Shani Itamar , Luhmann Heiko J. , Shamir Maoz
Published: March 2015

Identifying the properties of correlations in the firing of neocortical neurons is central to our understanding of cortical information processing. It has been generally assumed, by virtue of the columnar organization of the neocortex, that the firing of neurons residing in a certain vertical domain is highly correlated. On the other hand, firing correlations between neurons steeply decline with horizontal distance. Technical difficulties in sampling neurons with sufficient spatial information have precluded the critical evaluation of these notions. We used 128-channel “silicon probes” to examine the spike-count noise correlations during spontaneous activity between multiple neurons with identified laminar position and over large horizontal distances in the anesthetized rat barrel cortex. Eigen decomposition of correlation coefficient matrices revealed that the laminar position of a neuron is a significant determinant of these correlations, such that the fluctuations of layer 5B/6 neurons are in opposite direction to those of layers 5A and 4. Moreover, we found that within each experiment, the distribution of horizontal, intralaminar spike-count correlation coefficients, up to a distance of ∼1.5 mm, is practically identical to the distribution of vertical correlations. Taken together, these data reveal that the neuron's laminar position crucially affects its role in cortical processing. Moreover, our analyses reveal that this laminar effect extends over several functional columns. We propose that within the cortex the influence of the horizontal elements exists in a dynamic balance with the influence of the vertical domain and this balance is modulated with brain states to shape the network's behavior.
Characterization of Strong and Crystalline Polyvinyl Alcohol/Montmorillonite Films Prepared by Layer-by-Layer Deposition Method
Authors: Gaidukov S. , Danilenko I. , Gaidukova G.
Published: March 2015

The preparation of a high-strength and highly crystalline nanocomposite with a layered structure by the use of layer-by-layer deposition (LbL) method from polyvinyl alcohol (PVOH) and montmorillonite (MMT) platelets is reported. The crystallinity and interactions between the components were studied by the use of Fourier transform infrared spectroscopy (FT-IR), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The nanocomposite film structure was investigated by the use of scanning electron microscope (SEM) and atomic force microscopy (AFM). The stiffness of the LbL PVOH/MMT film was significantly higher compared to pure PVOH and conventional PVOH/MMT nanocomposite. The structural and thermal studies on thin PVOH/MMT films indicated the enhanced crystallinity of the polymer.
Analysis of Human Standing Balance by Largest Lyapunov Exponent
Authors: Liu Kun , Wang Hongrui , Xiao Jinzhuang , Taha Zahari
Published: March 2015

The purpose of this research is to analyse the relationship between nonlinear dynamic character and individuals’ standing balance by the largest Lyapunov exponent, which is regarded as a metric for assessing standing balance. According to previous study, the largest Lyapunov exponent from centre of pressure time series could not well quantify the human balance ability. In this research, two improvements were made. Firstly, an external stimulus was applied to feet in the form of continuous horizontal sinusoidal motion by a moving platform. Secondly, a multiaccelerometer subsystem was adopted. Twenty healthy volunteers participated in this experiment. A new metric, coordinated largest Lyapunov exponent was proposed, which reflected the relationship of body segments by integrating multidimensional largest Lyapunov exponent values. By using this metric in actual standing performance under sinusoidal stimulus, an obvious relationship between the new metric and the actual balance ability was found in the majority of the subjects. These results show that the sinusoidal stimulus can make human balance characteristics more obvious, which is beneficial to assess balance, and balance is determined by the ability of coordinating all body segments.
Assessment of Cell-Cycle Arrest Biomarkers to Predict Early and Delayed Acute Kidney Injury
Authors: Bell Max , Larsson Anders , Venge Per , Bellomo Rinaldo , Mårtensson Johan
Published: March 2015

Purpose. To assess urinary tissue inhibitor of metalloproteinases-2 and insulin-like growth factor binding protein 7 ([TIMP-2]·[IGFBP7]), urinary neutrophil gelatinase-associated lipocalin (NGAL), and urinary cystatin-C as acute kidney injury predictors (AKI) exploring the association of nonrenal factors with elevated biomarker levels.Methods. We studied 94 patients with urine collected within 48 hours of ICU admission and no AKI at sampling. AKI was defined by the Kidney Disease: Improving Global Outcomes criteria. Predictive performance was assessed by the area under the receiver operating characteristics (ROC) curve. Associations between biomarkers and clinical factors were assessed by multivariate linear regression.Results. Overall, 19 patients (20%) developed AKI within 48 hours. [TIMP-2]·[IGFBP7], NGAL, or cystatin-C admission levels did not differ between patients without AKI and patients developing AKI. [TIMP-2]·[IGFBP7], NGAL, and cystatin-C were poor AKI predictors (ROC areas 0.34–0.51). Diabetes was independently associated with higher [TIMP-2]·[IGFBP7] levels (P=0.02) but AKI was not (P=0.24). Sepsis was independently associated with higher NGAL (P<0.001) and cystatin-C (P=0.003) levels.Conclusions. Urinary [TIMP-2]·[IGFBP7], NGAL, and cystatin-C should be used cautiously as AKI predictors in general ICU patients since urine levels of these biomarkers are affected by factors other than AKI and their performance can be poor.
Twenty-Four-Hour Urine Osmolality as a Physiological Index of Adequate Water Intake
Authors: Perrier Erica T. , Buendia-Jimenez Inmaculada , Vecchio Mariacristina , Armstrong Lawrence E. , Tack Ivan , Klein Alexis
Published: March 2015

While associations exist between water, hydration, and disease risk, research quantifying the dose-response effect of water on health is limited. Thus, the water intake necessary to maintain optimal hydration from a physiological and health standpoint remains unclear. The aim of this analysis was to derive a 24 h urine osmolality (UOsm) threshold that would provide an index of “optimal hydration,” sufficient to compensate water losses and also be biologically significant relative to the risk of disease. Ninety-five adults (31.5 ± 4.3 years, 23.2 ± 2.7 kg·m−2) collected 24 h urine, provided morning blood samples, and completed food and fluid intake diaries over 3 consecutive weekdays. A UOsmthreshold was derived using 3 approaches, taking into account European dietary reference values for water; total fluid intake, and urine volumes associated with reduced risk for lithiasis and chronic kidney disease and plasma vasopressin concentration. The aggregate of these approaches suggest that a 24 h urine osmolality ≤500 mOsm·kg−1may be a simple indicator of optimal hydration, representing a total daily fluid intake adequate to compensate for daily losses, ensure urinary output sufficient to reduce the risk of urolithiasis and renal function decline, and avoid elevated plasma vasopressin concentrations mediating the increased antidiuretic effort.
A DE-Based Scatter Search for Global Optimization Problems
Authors: Li Kun , Tian Huixin
Published: March 2015

This paper proposes a hybrid scatter search (SS) algorithm for continuous global optimization problems by incorporating the evolution mechanism of differential evolution (DE) into the reference set updated procedure of SS to act as the new solution generation method. This hybrid algorithm is called a DE-based SS (SSDE) algorithm. Since different kinds of mutation operators of DE have been proposed in the literature and they have shown different search abilities for different kinds of problems, four traditional mutation operators are adopted in the hybrid SSDE algorithm. To adaptively select the mutation operator that is most appropriate to the current problem, an adaptive mechanism for the candidate mutation operators is developed. In addition, to enhance the exploration ability of SSDE, a reinitialization method is adopted to create a new population and subsequently construct a new reference set whenever the search process of SSDE is trapped in local optimum. Computational experiments on benchmark problems show that the proposed SSDE is competitive or superior to some state-of-the-art algorithms in the literature.
The Relationship between Estimated Glomerular Filtration Rate and Diabetic Retinopathy
Authors: Wu Jingyang , Geng Jin , Liu Limin , Teng Weiping , Liu Lei , Chen Lei
Published: March 2015

Diabetic retinopathy (DR) is the leading cause of visual impairment and blindness in working-aged people. Several studies have suggested that glomerular filtration rate (GFR) was correlated with DR. This is a hospital-based study and the aim of it was to examine the relationship between the GFR and DR in patients with type 2 diabetes mellitus (T2DM). We used CKD-EPI equation to estimate GFR and SPSS 19.0 and EmpowerStats software to assess their relationship. Among the 1613 participants (aged 54.75 ± 12.19 years), 550 (34.1%) patients suffered from DR. The multivariate analysis revealed that the risk factors for DR include age (P<0.001, OR = 0.940), duration of diabetes (P<0.001, OR = 1.163), hemoglobin A1c (P=0.007, OR = 1.224), systolic blood pressure (P<0.001, OR = 1.032), diastolic blood pressure (P=0.007, OR = 0.953), high density lipoprotein cholesterol (P=0.024, OR = 3.884), and eGFR (P=0.010, OR = 0.973). Through stratified analysis and saturation effect analysis, our data suggests that eGFR of 99.4 mL/min or lower might imply the early stage of DR in diabetic patients. Thus, the evaluation of eGFR has clinical significance for the early diagnosis of DR.
A Study on the Enhanced Best Performance Algorithm for the Just-in-Time Scheduling Problem
Authors: Chetty Sivashan , Adewumi Aderemi O.
Published: March 2015

The Just-In-Time (JIT) scheduling problem is an important subject of study. It essentially constitutes the problem of scheduling critical business resources in an attempt to optimize given business objectives. This problem is NP-Hard in nature, hence requiring efficient solution techniques. To solve the JIT scheduling problem presented in this study, a new local search metaheuristic algorithm, namely, the enhanced Best Performance Algorithm (eBPA), is introduced. This is part of the initial study of the algorithm for scheduling problems. The current problem setting is the allocation of a large number of jobs required to be scheduled on multiple and identical machines which run in parallel. The due date of a job is characterized by a window frame of time, rather than a specific point in time. The performance of the eBPA is compared against Tabu Search (TS) and Simulated Annealing (SA). SA and TS are well-known local search metaheuristic algorithms. The results show the potential of the eBPA as a metaheuristic algorithm.
Naturally Occurring Anthraquinones: Chemistry and Therapeutic Potential in Autoimmune Diabetes
Authors: Chien Shih-Chang , Wu Yueh-Chen , Chen Zeng-Weng , Yang Wen-Chin
Published: March 2015

Anthraquinones are a class of aromatic compounds with a 9,10-dioxoanthracene core. So far, 79 naturally occurring anthraquinones have been identified which include emodin, physcion, cascarin, catenarin, and rhein. A large body of literature has demonstrated that the naturally occurring anthraquinones possess a broad spectrum of bioactivities, such as cathartic, anticancer, anti-inflammatory, antimicrobial, diuretic, vasorelaxing, and phytoestrogen activities, suggesting their possible clinical application in many diseases. Despite the advances that have been made in understanding the chemistry and biology of the anthraquinones in recent years, research into their mechanisms of action and therapeutic potential in autoimmune disorders is still at an early stage. In this paper, we briefly introduce the etiology of autoimmune diabetes, an autoimmune disorder that affects as many as 10 million worldwide, and the role of chemotaxis in autoimmune diabetes. We then outline the chemical structure and biological properties of the naturally occurring anthraquinones and their derivatives with an emphasis on recent findings about their immune regulation. We discuss the structure and activity relationship, mode of action, and therapeutic potential of the anthraquinones in autoimmune diabetes, including a new strategy for the use of the anthraquinones in autoimmune diabetes.
Adult Vascular Wall Resident Multipotent Vascular Stem Cells, Matrix Metalloproteinases, and Arterial Aneurysms
Authors: Amato Bruno , Compagna Rita , Amato Maurizio , Grande Raffaele , Butrico Lucia , Rossi Alessio , Naso Agostino , Ruggiero Michele , de Franciscis Stefano , Serra Raffaele
Published: March 2015

Evidences have shown the presence of multipotent stem cells (SCs) at sites of arterial aneurysms: they can differentiate into smooth muscle cells (SMCs) and are activated after residing in a quiescent state in the vascular wall. Recent studies have implicated the role of matrix metalloproteinases in the pathogenesis of arterial aneurysms: in fact the increased synthesis of MMPs by arterial SMCs is thought to be a pivotal mechanism in aneurysm formation. The factors and signaling pathways involved in regulating wall resident SC recruitment, survival, proliferation, growth factor production, and differentiation may be also related to selective expression of different MMPs. This review explores the relationship between adult vascular wall resident multipotent vascular SCs, MMPs, and arterial aneurysms.
Location of Bioelectricity Plants in the Madrid Community Based on Triticale Crop: A Multicriteria Methodology
Authors: Romero L. , Romero M. S. , Cuadrado M. L. , Fernández J.
Published: March 2015

This paper presents a work whose objective is, first, to quantify the potential of the triticale biomass existing in each of the agricultural regions in the Madrid Community through a crop simulation model based on regression techniques and multiple correlation. Second, a methodology for defining which area has the best conditions for the installation of electricity plants from biomass has been described and applied. The study used a methodology based on compromise programming in a discrete multicriteria decision method (MDM) context. To make a ranking, the following criteria were taken into account: biomass potential, electric power infrastructure, road networks, protected spaces, and urban nuclei surfaces. The results indicate that, in the case of the Madrid Community, the Campiña region is the most suitable for setting up plants powered by biomass. A minimum of 17,339.9 tons of triticale will be needed to satisfy the requirements of a 2.2 MW power plant. The minimum range of action for obtaining the biomass necessary in Campiña region would be 6.6 km around the municipality of Algete, based on Geographic Information Systems. The total biomass which could be made available in considering this range in this region would be 18,430.68 t.
Intelligent Topical Sentiment Analysis for the Classification of E‐Learners and Their Topics of Interest
Authors: Ravichandran M. , Kulanthaivel G. , Chellatamilan T.
Published: March 2015

Every day, huge numbers of instant tweets (messages) are published on Twitter as it is one of the massive social media for e‐learners interactions. The options regarding various interesting topics to be studied are discussed among the learners and teachers through the capture of ideal sources in Twitter. The common sentiment behavior towards these topics is received through the massive number of instant messages about them. In this paper, rather than using the opinion polarity of each message relevant to the topic, authors focus on sentence level opinion classification upon using the unsupervised algorithm named bigram item response theory (BIRT). It differs from the traditional classification and document level classification algorithm. The investigation illustrated in this paper is of threefold which are listed as follows: (1) lexicon based sentiment polarity of tweet messages; (2) the bigram cooccurrence relationship using naïve Bayesian; (3) the bigram item response theory (BIRT) on various topics. It has been proposed that a model using item response theory is constructed for topical classification inference. The performance has been improved remarkably using this bigram item response theory when compared with other supervised algorithms. The experiment has been conducted on a real life dataset containing different set of tweets and topics.
Coupled Scalar Fields Oscillons and Breathers in Some Lorentz Violating Scenarios
Authors: Correa R. A. C. , Dutra A. de Souza
Published: March 2015

We discuss the impact of the breaking of the Lorentz symmetry on the usual oscillons, the so-called flat-top oscillons, and the breathers. Our analysis is performed by using a Lorentz violation scenario rigorously derived in the literature. We show that the Lorentz violation is responsible for the origin of a kind of deformation of the configuration, where the field configuration becomes oscillatory in a localized region near its maximum value. Furthermore, we show that the Lorentz breaking symmetry produces a displacement of the oscillon along the spatial direction; the same feature is present in the case of breathers. We also show that the effect of a Lorentz violation in the flat-top oscillon solution is responsible by the shrinking of the flat-top. Furthermore, we find analytically the outgoing radiation; this result indicates that the amplitude of the outgoing radiation is controlled by the Lorentz breaking parameter, in such a way that this oscillon becomes more unstable than its symmetric counterpart; however, it still has a long living nature.
Aeroservoelastic Pitch Control of Stall-Induced Flap/Lag Flutter of Wind Turbine Blade Section
Authors: Liu Tingrui
Published: March 2015

The aim of this paper is to analyze aeroelastic stability, especially flutter suppression for aeroelastic instability. Effects of aeroservoelastic pitch control for flutter suppression on wind turbine blade section subjected to combined flap and lag motions are rarely studied. The work is dedicated to solving destructive flapwise and edgewise instability of stall-induced flutter of wind turbine blade by aeroservoelastic pitch control. The aeroelastic governing equations combine a flap/lag structural model and an unsteady nonlinear aerodynamic model. The nonlinear resulting equations are linearized by small perturbation about the equilibrium point. The instability characteristics of stall-induced flap/lag flutter are investigated. Pitch actuator is described by a second-order model. The aeroservoelastic control is analyzed by three types of optimal PID controllers, two types of fuzzy PID controllers, and neural network PID controllers. The fuzzy controllers are developed based on Sugeno model and intuition method with good results achieved. A single neuron PID control strategy with improved Hebb learning algorithm and a radial basic function neural network PID algorithm are applied and performed well in the range of extreme wind speeds.
Three-Point Boundary Value Problems for Conformable Fractional Differential Equations
Authors: Batarfi H. , Losada Jorge , Nieto Juan J. , Shammakh W.
Published: March 2015

We study a fractional differential equation using a recent novel concept of fractional derivative with initial and three-point boundary conditions. We first obtain Green's function for the linear problem and then we study the nonlinear differential equation.
Treatment of Nonalcoholic Steatohepatitis in Adults: Present and Future
Authors: Gitto S. , Vitale G. , Villa E. , Andreone P.
Published: March 2015

Nonalcoholic steatohepatitis has become one of the most common liver-related health problems. This condition has been linked to an unhealthy diet and weight gain, but it can also be observed in nonobese people. The standard of care is represented by the lifestyle intervention. However, because this approach has several limitations, such as a lack of compliance, the use of many drugs has been proposed. The first-line pharmacological choices are vitamin E and pioglitazone, both showing a positive effect on transaminases, fat accumulation, and inflammation. Nevertheless, vitamin E has no proven effect on fibrosis and on long-term morbidity and mortality and pioglitazone has a negative impact on weight. Other drugs have been studied such as metformin, ursodeoxycholic acid, statins, pentoxiphylline, and orlistat with only partially positive results. Among the emerging treatments, telmisartan is particularly interesting as it seems to have an impact on insulin resistance, liver steatosis, inflammation, and fibrosis. However, the pathogenesis of steatohepatitis is highly complex and is determined by different parallel hits; indeed, the association of different drugs that act on various levels has been suggested. In conclusion, lifestyle intervention should be optimised and the associations of different drugs should be tested in large studies with long-term outcomes.
Changes in the Conformational State of Hemoglobin in Hemodialysed Patients with Chronic Renal Failure
Authors: Pieniazek Anna , Gwozdzinski Krzysztof
Published: March 2015

The aim of this study was to evaluate the properties of internal components of erythrocytes in chronic renal failure (CRF) patients undergoing hemodialysis (HD) in comparison to control subjects. For investigation of conformational state of hemoglobin and nonheme proteins (NHP) the maleimide spin label (MSL) in electron paramagnetic resonance (EPR) was applied. The studies were performed using MSL in whole cells and hemolysate as well as proteins separated by ion exchange chromatography and checked by electrophoresis. Additionally the level of –SH groups in hemolysate and isolated internal proteins of CRF erythrocytes was determined using 4,4′-dithiodipyridine. All measurements were performed before and after hemodialysis. Oxidative stress accompanying CRF/hemodialysed patients caused a significant decrease in the mobility of internal components inside erythrocytes indicated by MSL (P< 0.02). The significant decrease in mobility of spin labeled HbA1cand HbA both before and after HD (P< 0.0002) as well as in nonheme proteins before hemodialysis (P< 0.05) versus control was indicated. Decrease in mobility of internal components of erythrocytes was accompanied by loss of thiols before and after hemodialysis versus control in NHP (P< 0.05), HbA1c(P< 0.0002), and HbA (P< 0.0005). These findings showed oxidative influence of hemodialysis on hemoglobins and internal nonheme proteins in erythrocytes of CRF patients.
Trichostatin A-Mediated Epigenetic Transformation of Adult Bone Marrow-Derived Mesenchymal Stem Cells Biases theIn VitroDevelopmental Capability, Quality, and Pluripotency Extent of Porcine Cloned Embryos
Authors: Samiec Marcin , Opiela Jolanta , Lipiński Daniel , Romanek Joanna
Published: March 2015

The current research was conducted to explore thein vitrodevelopmental outcome and cytological/molecular quality of porcine nuclear-transferred (NT) embryos reconstituted with adult bone marrow-derived mesenchymal stem cells (ABM-MSCs) that were epigenetically transformed by treatment with nonspecific inhibitor of histone deacetylases, known as trichostatin A (TSA). The cytological quality of cloned blastocysts was assessed by estimation of the total cells number (TCN) and apoptotic index. Their molecular quality was evaluated by real-time PCR-mediated quantification of gene transcripts for pluripotency- and multipotent stemness-related markers (Oct4, Nanog, andNestin). The morula and blastocyst formation rates of NT embryos derived from ABM-MSCs undergoing TSA treatment were significantly higher than in the TSA-unexposed group. Moreover, the NT blastocysts generated using TSA-treated ABM-MSCs exhibited significantly higher TCN and increased pluripotency extent measured with relative abundance ofOct4andNanogmRNAs as compared to the TSA-untreated group. Altogether, the improvements in morula/blastocyst yields and quality of cloned pig embryos seem to arise from enhanced abilities for promotion of correct epigenetic reprogramming of TSA-exposed ABM-MSC nuclei in a cytoplasm of reconstructed oocytes. To our knowledge, we are the first to report the successful production of mammalian high-quality NT blastocysts using TSA-dependent epigenomic modulation of ABM-MSCs.
Gambogic Acid Lysinate Induces Apoptosis in Breast Cancer MCF-7 Cells by Increasing Reactive Oxygen Species
Authors: Zhen Yong-Zhan , Lin Ya-Jun , Li Kai-Ji , Yang Xiao-Shan , Zhao Yu-Fang , Wei Jie , Wei Jing-Bo , Hu Gang
Published: March 2015

Gambogic acid (GA) inhibits the proliferation of various human cancer cells. However, because of its water insolubility, the antitumor efficacy of GA is limited.Objectives.To investigate the antitumor activity of gambogic acid lysinate (GAL) and its mechanism.Methods.Inhibition of cell proliferation was determined by MTT assay; intracellular ROS level was detected by staining cells with DCFH-DA; cell apoptosis was determined by flow cytometer and the mechanism of GAL was investigated by Western blot.Results.GAL inhibited the proliferation of MCF-7 cells with IC50values 1.46 μmol/L comparable with GA (IC50, 1.16 μmol/L). GAL promoted the production of ROS; however NAC could remove ROS and block the effect of GAL. GAL inhibited the expression of SIRT1 but increased the phosphorylation of FOXO3a and the expression of p27Kip1. At knockdown of FOXO3a, cell apoptosis induced by GAL can be partly blocked. In addition it also enhanced the cleavage of caspase-3.Conclusions.GAL inhibited MCF-7 cell proliferation and induced MCF-7 cell apoptosis by increasing ROS level which could induce cell apoptosis by both SIRT1/FOXO3a/p27Kip1 and caspase-3 signal pathway. These results suggested that GAL might be useful as a modulation agent in cancer chemotherapy.
Chemosensitivity of Anaplastic Thyroid Cancer Based on a Histoculture Drug Response Assay
Authors: Uruno Takashi , Masaki Chie , Akaishi Junko , Matsuzu Kenichi , Suzuki Akifumi , Ohkuwa Keiko , Shibuya Hiroshi , Kitagawa Wataru , Nagahama Mitsuji , Sugino Kiminori , Ito Koichi
Published: March 2015

The chemosensitivity of anaplastic thyroid cancer (ATC) to some cytotoxic agents was investigated by the histoculture drug response assay (HDRA). Thirty specimens from 22 patients with ATC were obtained from surgically resected subjects. The drugs tested were paclitaxel (PTX), docetaxel (DOC), adriamycin (ADM), nedaplatin (254-S), cisplatin (CDDP), carboplatin (CBDCA), etoposide (VP-16), 5-fluorouracil (5-FU), mitomycin C (MMC), and cyclophosphamide (CPA). PTX was the most effective agent, and 25 of 29 cases (86.2%) had high inhibition rates (IRs; over 70%), while DOC, another taxane, had lower IRs (median, 32.6%). 254-S had the second highest IR (median 68.1%), higher than other platins, CDDP (median 47.3%) and CBDCA (median 27.4%). The IR of 50% dose PTX (20 μg/mL, median 30.6%) was markedly decreased, while that of 50% dose 254-S (10 μg/mL, median 63.3%) still retained its inhibition effect compared to 100% dose. Most recurrent samples had higher IRs than primary lesions, but the IRs of different drugs differed between primary and recurrent lesions, even with samples from the same patients. PTX has a higher IR to ATC tissues in the HDRA, which suggests that it may be a key drug for the treatment of patients with ATC.
Evolutionary Game-Based Secrecy Rate Adaptation in Wireless Sensor Networks
Authors: Jiang Guanxiong , Shen Shigen , Hu Keli , Huang Longjun , Li Hongjie , Han Risheng
Published: March 2015

Physical layer security, whose aim is to maximize the secrecy rate of a source while keeping eavesdroppers ignorant of data transmitted, is extremely suitable for Wireless Sensor Networks (WSNs). We therefore, by developing the classical wire-tap channel, construct an approach to compute the secrecy rate between a sensor node and its responsible cluster head in the clustered WSNs. A noncooperative secrecy rate game towards WSNs is formulated to solve contradictions between maximizing the secrecy rate of a sensor node and minimizing power consumed for data transmission. Using evolutionary game theory, we set up a selection dynamics upon which a power level can be adaptively selected by a sensor node. Thus, the objective of secrecy rate adaptation for maximizing the fitness of member sensor nodes is achieved. We also prove the game is stable; that is, there exist evolutionarily stable strategies (ESSs) that explain which strategies will be selected by a sensor node in the end. Moreover, a corresponding algorithm of secrecy rate adaptation is given. Numerical experiments show our proposed approach can adaptively adjust the secrecy rate of a sensor node, which provides a novel way to guarantee the confidentiality of WSNs.
Effects of Sildenafil on Ventricular and Vascular Function in Heart Failure With Preserved Ejection Fraction
Authors: Borlaug Barry A. , Lewis Gregory D. , McNulty Steven E. , Semigran Marc J. , LeWinter Martin , Chen Horng , Lin Grace , Deswal Anita , Margulies Kenneth B. , Redfield Margaret M.
Published: March 2015

Background—

Early studies showed beneficial effects of phosphodiesterase 5 inhibitors on cardiovascular function in heart failure (HF) patients, but the RELAX trial observed no improvement in exercise capacity with sildenafil treatment in subjects with HF and preserved ejection fraction.

Methods and Results—

A subgroup of participants in the RELAX trial (n=48) underwent comprehensive noninvasive cardiovascular assessment before and after treatment with sildenafil or placebo in a prospective ancillary study. Left ventricular contractility was assessed by peak power index and stroke work index. Systemic arterial load was assessed by arterial elastance (Ea) and right ventricular afterload by pulmonary artery systolic pressure. Endothelial function was assessed by reactive hyperemia index after upper arm cuff occlusion. Compared with placebo (n=25), sildenafil (n=23) decreased Ea (−0.29±0.28 mm Hg/mL versus +0.02±0.29,
P
=0.008) and tended to improve reactive hyperemia index (+0.30±0.45 versus −0.17±0.30,
P
=0.054). In contrast, left ventricular contractility was reduced by 11% to 16% with sildenafil compared with placebo (ΔPWR/EDV −52±70 versus +0±40 mm Hg/s,
P
=0.006; ΔSW/EDV +0.3±5.8 versus −6.0±5.1 mm Hg,
P
=0.04). Sildenafil had no effect on pulmonary artery systolic pressure.

Conclusions—

In subjects with HF and preserved ejection fraction, sildenafil displayed opposing effects on ventricular and vascular function. We speculate that beneficial effects of phosphodiesterase 5 inhibitors in the systemic vasculature and endothelium were insufficient to improve clinical status or that the deleterious effects on left ventricular function offset any salutary vascular effects, contributing to the absence of benefit observed with sildenafil in subjects with HF and preserved ejection fraction in the RELAX trial.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00094302.
Fixed-Dose Combination Treatment After Stroke for Secondary Prevention in China
Authors: Longde Wang , Ling Yin , Yang Hua , Yi Zuo , Yongjun Wang , Xunming Ji , Xiaoyuan Niu , Qiumin Qu , Li He , Yuming Xu , Mei Li , Jiayi Sun , Jing Liu , Dong Zhao
Published: March 2015

Background and Purpose—

There is evidence and international consensus on the advantages and potential of a polypill for established cardiovascular disease patients to improve adherence in the secondary prevention of cardiovascular disease. This study aimed to estimate the numbers of stroke patients who would be eligible for the polypill strategy in China, and the suitable composition of a polypill, based on data of the China National Stroke Prevention Project.

Methods—

A total of 717 620 residents aged ≥40 years from 6 Chinese representative provinces were screened for prevalent stroke from 2011 to 2012 with an 84.4% response rate. Participants with a history of stroke received further investigation of risk factors and treatments. The potential need for treatment was classified according to the guidelines. Rates were standardized using the population composition of the Sixth National Population Census of China.

Results—

The standardized prevalence rate of stroke was 1.9%. Up to 93.1% of stroke patients were eligible for a polypill containing at least 2 types of medications, with 75.3% eligible for a statin and antiplatelet agent and 70.6% for antihypertensive and antiplatelet medications. Considering 3 therapies, 54% were eligible for antihypertensive, statin, and antiplatelet medications. The current treatment rate with all required combinations of separate pills was only 6.9%.

Conclusions—

A huge number of stroke patients in China require preventive therapy and would be eligible for a polypill. This study indicates that it would be reasonable to consider and assess the value of a polypill strategy to improve secondary prevention of stroke in China.
Paralasianthus (Rubiaceae), a new genus from Southeast Asia
Authors: Hua Zhu
Published: March 2015

The new genus Paralasianthus is described from South-East Asia. Five species are recognised in the genus, four of which required new combinations, P. brevipes, P. dichotomus, P. lowianus and P. hainanensis, and one is described as a new species, P. zhengyianus. A key to the species is presented.
Homalopetalum joinvillense (Epidendreae; Epidendroideae; Orchidaceae): a new species from Southern Brazil
Authors: Mancinelli Werner Siebje , DE CAMARGO SMIDT ERIC
Published: March 2015

Homalopetalum joinvillense (Orchidaceae) is a new species found in Joinville (Brazil). This species presents morphological similarity with Homalopetalum alticolum, but it differs from that and another species of this genus by a combination of an oblong-obovate lip with a slightly denticulate lip margin, a callus divided in two parts, globose in the internal part and conical in the external part, and an erose clinandrium. This article presents the complete description and the illustration of the new species, as well as an identification key for the genus.