bluuebunny/crossref_metadata_2025 huggingface dataset:
Long‐term experience of steroid‐free pediatric renal transplantation: Effects on graft function, body mass index, and longitudinal growth
Authors: Wittenhagen Per , Thiesson Helle C. , Baudier François , Pedersen Erik B. , Neland Mette
Published: November 2013

Increased focus on the potential negative side effects of steroid usage in pediatric transplantation has led to steroid minimization or steroid‐free transplantation. In this study, we report results after complete steroid avoidance in renal transplantation in the period 1994–2009. We evaluate the effects of complete steroid avoidance on allograft function, BMI, and linear growth. The majority of transplanted children were induced with antithymocyte globulin and immunosuppressed with a calcineurin inhibitor and mycophenolate mofetil. Steroids were given only when rejection occurred or due to comorbidities. Anthropometric data were collected from 65 transplantations in 60 children. Patient survival was 93%; graft survival was 81% after five yr (N = 42) and 63% after 10 yr (N = 16). Acute rejection within the first year of transplantation was 9%. The distribution of the children's BMI before transplantation was normal; the mean BMI‐SDS was 0.21 before transplantation, and this value remained stable during the next five yr. Post‐transplantation the children demonstrated significant improved growth as the mean height‐SDS increased significantly from −1.7 to −1.1. Catch‐up growth was most pronounced in the youngest (< six yr). Steroid‐free immunosuppression in pediatric renal transplantation is safe and protects against steroid‐induced obesity and short stature.
Theorizing the US Racial State: Sociology Since Racial Formation
Authors: Jung Moon‐Kie , Kwon Yaejoon
Published: November 2013

This article reviews theoretical developments in the sociology of the US racial state since the publication of Michael Omi and Howard Winant's groundbreaking Racial Formation in the United States. After briefly outlining their theory, it surveys the still diminutive literature and concludes by pointing to promising future directions, drawing on insights from other disciplines and incipient stirrings from within sociology. Destabilizing the unquestioned assumption that the United States is and has been a nation‐state, the article reconceptualizes it as an empire‐state. This turn establishes a firmer footing for the claim that the United States is intrinsically a racial state and yields a generative framework for reconsidering and stimulating scholarship toward more effective analysis and critique.
Studying Social Movements: Challenges and Opportunities for Participant Observation
Authors: Uldam Julie , McCurdy Patrick
Published: November 2013

The research method of participant observation has long been used by scholars interested in the motivations, dynamics, tactics and strategies of social movements from a movement perspective. Despite participant observation being a common research method, there have been very few efforts to bring together this literature, which has often been spread across disciplines. This makes it difficult to identify the various challenges (and their interrelation) facing participant observers. Consequently, this article first reviews how participant observation roles have been conceptualised in general and then draws specific links to how the method has been used in the study of activism and social movements. In doing so, this article brings together key academic debates on participant observation, which have been considered separately, such as insider/outsider and overt/covert, but not previously been brought together.
A Modified Particle Swarm Optimization Algorithm for the Design of a Double-Pad Aerostatic Bearing With a Pocketed Orifice-Type Restrictor
Authors: Chang S. H. , Jeng Y. R.
Published: November 2013

The performance of an aerostatic bearing with a pocketed orifice-type restrictor is affected by the bearing size, pocket size, orifice design, supply pressure, and bearing load. This study proposes a modified particle swarm optimization (MPSO) algorithm to optimize a double-pad aerostatic bearing. In bearing optimization, the upper and lower bearing designs are independent and several design variables that affect bearing performance must be considered. This study also applies the concept of mutation from a genetic algorithm. The results show that the MPSO algorithm has a global search capability and high efficiency to optimize a problem with several design variables and that the mutation can provide an avenue for particles to escape from a local optimal value.
Response of Fractional Oscillators With Viscoelastic Term Under Random Excitation
Authors: Xu Yong , Li Yongge , Liu Di
Published: November 2013

A system with fractional damping and a viscoelastic term subject to narrow-band noise is considered in this paper. Based on the revisit of the Lindstedt–Poincaré (LP) and multiple scales method, we present a new procedure to obtain the second-order approximate analytical solution, and then the frequency–amplitude response equations in the deterministic case and the first- and second-order steady-state moments in the stochastic case are derived theoretically. Numerical simulation is applied to verify the effectiveness of the proposed method, which shows good agreement with the analytical results. Specially, we find that the new method is valid for strongly nonlinear systems. In addition, the influences of fractional order and the viscoelastic parameter on the system are explored, and the results indicate that the steady-state amplitude will increase at a fixed point with the increase of fractional order or viscoelastic parameter. At last, stochastic jump is investigated via the received Fokker–Planck–Kolmogorov (FPK) equation to compute the stationary solution of probability density functions with its shape changing from one peak to two peaks with the increase of noise intensity, and the phenomena of stochastic jump is consistent with the solution of frequency–amplitude response equations.
Knitting Up the Raveled Sleave of Care
Authors: Yang Guangrui , Paschos Georgios , Curtis Anne M. , Musiek Erik S. , McLoughlin Sarah C. , FitzGerald Garret A.
Published: November 2013

Recent advances in our understanding of molecular clocks highlight their relevance to human physiology and disease.
Evidence for an Early Pleistocene glaciation in the Okanagan Valley, southern British Columbia
Authors: Roed Murray A. , Barendregt René W. , Benowitz Jeff A. , Smith C.A.S. , Sanborn P.T. , Greenough John D. , Huscroft Crystal , Layer Paul W. , Mathewes Rolf W. , Tessler Dez
Published: November 2013

Depositional evidence of Early Pleistocene glaciations in British Columbia are documented at only a few sites. Near Kelowna, in southern British Columbia, a construction project exposed glacial sediments beneath Lambly Creek Basalt, providing a minimum age for this glaciation. The basalt is composed of a number of flows yielding ages that range from 0.76 ± 0.11 to 1.5 ± 0.1 Ma. The sediments consist of a diamicton, interpreted to be till, up to 3 m thick mantled by a weakly developed paleosol. The diamicton is underlain by fluvial sands up to 5 m thick, in places revealing injection features, and minor faulting. A unit of stratified gravel underlain by grey clay is inferred to underlie the exposed sediments, based on nearby outcrops and excavations. Sediments and overlying basalts are normally magnetized and are assigned to the Jaramillo normal subchron (1.069–0.987 Ma). The till is here referred to as the Westbank First Nation Till. It is Early Pleistocene in age and represents the earliest evidence of glaciation in the Okanagan Valley. Stone fabric analysis and clast lithologies suggest that ice movement was from northwest to southeast, and is here referred to as the West Kelowna Advance; we infer that this advance was part of a larger regional glaciation. Other Early Pleistocene glaciations in the Cordillera are briefly reviewed.
IMPROVED ESTIMATORS FOR THE RELIABILITY OF A SERIES SYSTEM
Authors: MAHAPATRA AJAYA KUMAR , KUMAR SOMESH , VELLAISAMY P.
Published: November 2013

The estimation of the reliability of a series system of k(≥ 2) independent components, where the life time of each component is exponentially distributed, has been considered. First, sufficient conditions for obtaining improvements over scale equivariant estimators for the one-parametric model are derived. As a consequence, we derive estimators that improve upon the maximum likelihood estimator (MLE), an analog of the uniformly minimum variance unbiased estimator (UMVUE) and the best-scale equivariant estimator (BSEE). Bayes and generalized Bayes estimators are also obtained and are shown to be admissible. We consider also the case where the lifetimes follow two-parametric exponential distributions and derive the UMVUE of the system reliability. Further, the MLE and the modified MLE (MMLE) are discussed for this case. Finally, the risks of these estimators are compared numerically for the case k = 2.
OPTIMAL COMPONENT SELECTION APPROACH FOR FAULT-TOLERANT SOFTWARE SYSTEM UNDER CRB INCORPORATING BUILD-OR-BUY DECISION
Authors: JHA P. C. , KAUR RAMANDEEP , BALI SHIVANI , MADAN SUSHILA
Published: November 2013

Application Package Software (APS) has emerged as a ready-to-use solution for the software industry. The software system comprises of a number of components which can be either purchased from the vendor in the form of COTS (Commercial Off-the-Shelf) or can be built in-house. Such a decision is known as Build-or-Buy decision. Under the situations wherein the software has the responsibility of supervising life-critical systems, the inception of errors in software due to inadequate or incomplete testing, is not acceptable. Such life-critical systems enforces upon meeting the quality standards of the software as unforbiddenable. This can be achieved by incorporating a fault-tolerant design that enables a system to continue its intended operation rather than failing completely when some part of the system fails. Moreover, while designing a fault-tolerant system, it must be apprehended that 100% fault tolerance can never be achieved and the closer we try to get to 100%, the more costly the system will be. The proposed model shall incorporate consensus recovery block scheme of fault tolerant techniques. Through this paper, we shall focus on build-or-buy decision for an APS in order to facilitate optimal component selection thereby, maximizing the reliability and minimizing the overall cost and source lines of code of the entire system. Further, since the proposed problem has incompleteness and unreliability of input information such as execution time and cost, hence, the environment in the proposed model is taken as fuzzy.
Weighted L2-invariants and applications to knot theory
Authors: Dubois Jérôme , Wegner Christian
Published: November 2013

This paper deals with the study of a new family of knot invariants: the L2-Alexander invariant. A main result is to give a method of computation of the L2-Alexander invariant of a knot complement using any presentation of default 1 of the knot group.
SYNTHESIS OF ZnS:Mn/SILICA CORE/SHELL MICROSPHERES WITH A COMBINATION OF SOL–GEL AND SELF-TEMPLATING TECHNIQUES
Authors: ZHANG QING
Published: November 2013

Core/shell microspheres with functional Mn -doped ZnS microspheres ( ZnS : Mn ) as core and with nanosilica particles as shell were prepared by a combination of sol–gel and self-templating techniques. The characteristic of this novel method was that the whole process required neither additional surfactant nor stabilizer, which exempted from removing the template and reduced reaction steps compared to the conventional process. The morphologies, structure and particle size distribution of the resulting ZnS : Mn / SiO 2 microspheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively. Surface chemical composition and optical properties were determined with X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) spectroscopy, respectively. In addition, the effects of reaction conditions on the structure and morphologies were investigated. Experimental results indicated that the resulting ZnS : Mn / SiO 2 microspheres were perfectly spherical with distinct core/shell structures, and exhibited stronger fluorescence emission.
BIAXIALLY ORIENTED POLYPROPYLENE FILM FOR AFM TIP CHARACTERIZATION
Authors: HAN GUOQIANG , CHEN YUQIN , HE BINGWEI
Published: November 2013

Atomic force microscopy (AFM) investigating the sample morphology is the process of direct interaction between tip and surface features. The geometry of probe tip is a determining factor in correcting AFM images distorted by tip size itself. A quantitative knowledge of the current tip shape is needed to improve the reliability of AFM images. The biaxially oriented polypropylene (BOPP) film was fabricated and used as tip characterizer to estimate the morphology of AFM Si tip based on the blind reconstruction algorithm. The surface of the BOPP film was covered by nanometer-scale-sized structures which ensure that the tip profile can be determined accurately. Without independent knowledge of the sample, the three-dimensional (3D) shape of Si probe tip was obtained with high aspect ratio. BOPP film is not only a simple, cheap material but also a soft one which can also avoid tip damage in scanning. It was demonstrated reliable and suitable for tip characterization.
TiO2 nanobelts: Acid corrosion, enhanced photocatalytic activity and CeO2 deposition
Authors: He Haiyan , Jia Changchao , Yang Ping
Published: November 2013

TiO 2 nanobelts are synthesized via a hydrothermal procedure. The rough surface can be obtained by sulfuric acid corrosion and TiO 2 nanoparticles were attached on the surface of the nanobelts. The concentration of sulfuric acid and corrosion temperature play important roles on the morphology and photocatalytic activity of TiO 2 nanobelts. The TiO 2 nanoparticles on the nanobelts enhanced the photocatalytic activity. TiO 2 nanobelts etched with sulfuric acid of 0.03 M at 120°C show the highest photocatalytic activity and the degradation rate of methyl orange reaches 84.64% after irradiated by the UV light for 2.5 h. With high concentration of sulfuric acid and corrosion temperature treated, belt-like structure would be broken, and even aggregated together, which weaken the photocatalytic activity. In addition, CeO 2/ TiO 2 nanobelt heterostructure is prepared through the process of chemical coprecipitation. The rough surface provides the nucleation sites for CeO 2, and the nanoparticles with small size can distribute on the surface of TiO 2 nanobelts.
Study of the Residual Strength of an RC Shear Wall with Fractal Crack Taking into Account Interlocking Interface Phenomena
Authors: Panagouli O. , Iordanidou K.
Published: November 2013

In the present paper, the postcracking strength of an RC shear wall element which follows the construction practices applied in Greece during the 70s is examined by taking into account the complex geometry of the crack of the wall and the mixed friction-plastification mechanisms that develop in the vicinity of the crack. Due to the significance of the crack geometry, a multiresolution analysis based on fractal geometry is performed, taking into account the size of the aggregates of concrete. The materials (steel and concrete) are assumed to have elastic-plastic behaviour. For concrete, both cracking and crushing are taken into account in an accurate manner. On the interfaces of the crack, unilateral contact and friction conditions are assumed to hold. For every structure corresponding to each resolution of the interface, a classical Euclidean problem is solved. The obtained results lead to interesting conclusions concerning the influence of the simulation of the geometry of the fractal crack on the mechanical interlock between the two faces of the crack, a factor which seems to be very important to the postcracking strength of the lightly reinforced shear wall studied here.
Strategy of Starting Sensorless BLDCM with Inductance Method and EMF Integration
Authors: Dafang Wang , Ji Qi , Cheng Zhu , Jiangmin Liao , Yechen Yuan
Published: November 2013

In, conventional 3-stage start-up method of sensorless brushless direct current motor (BLDCM), the rotor is likely to jitter because rotor position cannot be obtained, and the motor is apt to lose step when it starts with load. These defects limit its use in engineering applications. In order to achieve smooth start in specific direction and guarantee start-up success rate with load, a start-up method based on improved inductance method and electromotive force (EMF) integration is proposed applying different voltage vectors according to rotor position interval judged by inductance method and determining integrator start-up time according to rotor initial position and the EMF. Experiments show that the method guarantees smooth acceleration and increases start-up success rate with load.
Factorial Analysis of Welding Current Influence on Heat Affected Zone Hardness of Cast Iron, Aluminium, and Mild Steel Weldments Cooled in Palm Oil
Authors: Nwoye C. I. , Odo J. U. , Ameh E. M. , Nwakpa S. O.
Published: November 2013

Factorial analysis of heat affected zone hardness of some metals was evaluated. Three models were derived and used as tools for evaluating the welding current influence on the predictability of HAZ hardness in aluminium, cast iron, and mild steel weldments similarly cooled in palm oil. It was discovered that on welding these materials, and similarly cooling their respective weldments in palm oil, the model predicts aluminium weldment HAZ hardness by multiplying the determined general current product rule (GCPR) with the ratio: HAZ hardness product of cast iron and mild steel/HAZ hardness sum of cast iron and mild steel . Computational analysis of experimental and model-predicted results indicates that aluminium, cast iron, and mild steel weldment HAZ hardness per unit welding current as evaluated from experiment and derived model are 3.3917, 4.8333, and 2.7944 and 3.3915, 4.8335, and 2.7946 (VHN) A−1, respectively. Deviational analysis shows that the maximum deviation of model-predicted HAZ hardness from the experimental results is less than 0.007%. This invariably implies over 99.99 % confidence level for the derived models.
Evaluation of Serum 25-Hydroxyvitamin D as a Predictor of Carotid Intima-Media Thickness and Carotid Total Plaque Area in Nonsmokers: The Tromsø Study
Authors: Kamycheva Elena , Johnsen Stein Harald , Wilsgaard Tom , Jorde Rolf , Mathiesen Ellisiv B.
Published: November 2013

Objective. Altered calcium homeostasis has been linked to increased intima-media thickness (IMT) and plaques. We aimed to investigate whether serum 25-hydroxyvitamin D (25(OH)D) and serum calcium are associated with IMT and plaques in nonsmoking population.Methods. Ultrasound of the right carotid artery with the measurements of IMT and plaques was performed in 4194 nonsmoking subjects with available measurements of serum 25(OH)D and total calcium. Linear regression was applied to study the linear relationships between variables. Multinomial logistic regression was used to evaluate predictors of increased IMT and total plaque area (TPA), adjusted for age, body mass index, systolic blood pressure, and total cholesterol.Results. There was no significant linear relationship between mean IMT, TPA, and either serum 25(OH)D or total serum calcium. One SD increase in serum 25(OH)D was independently associated with increased odds of being in the highest quartile of IMT in men (OR 1.30, 95% CI 1.12, 1.51). In women, 1 SD increase in serum 25(OH)D was independently associated with increased risk of being in the upper tertile of TPA (OR 1.15, 95% CI 1.01, 1.33).Conclusions. Impaired calcium homeostasis has no consistent association with mean IMT and TPA; however, increased serum 25(OH)D may predict subclinical atherosclerosis in nonsmokers.
Experimental Study on Formation Characteristics and Laws of Dislocation and Stacking Fault during Cutting of Titanium Alloy
Authors: Yang Y. , Llu B.
Published: November 2013

Formation characteristics and laws of dislocation and stacking fault during cutting of titanium alloy were investigated by TEM. Several crucial aspects of experiment, such as sample cutting, mechanical reduction of thickness, dimpling, and ion reduction of thickness, were carefully designed and implemented. Further, electron diffraction pattern, diffraction contrast image, and high resolution electron photomicrograph ofαphase andβphase were observed and analyzed. Following those analyses, the formation characteristics and laws of dislocation and stacking fault were made clear. Research results show that the edge dislocations exist commonly in the diffraction contrast images and high resolution electron photomicrographs ofαphase andβphase. The stacking fault energy is higher inβphase than inαphase. In addition, the extended dislocation is difficult to be seen inβphase, but it is easier to be produced inαphase.
New Concept for Assessment of Tidal Current Energy in Jiangsu Coast, China
Authors: Zhang Ji-Sheng , Wang Jun , Tao Ai-Feng , Zheng Jin-Hai , Li Hui
Published: November 2013

Tidal current energy has attracted more and more attentions of coastal engineers in recent years, mainly due to its advantages of low environmental impact, long-term predictability, and large energy potential. In this study, a two-dimensional hydrodynamic model is applied to predict the distribution of mean density of tidal current energy and to determine a suitable site for energy exploitation in Jiangsu Coast. The simulation results including water elevation and tidal current (speed and direction) were validated with measured data, showing a reasonable agreement. Then, the model was used to evaluate the distribution of mean density of tidal current energy during springtide and neap tide in Jiangsu Coast. Considering the discontinuous performance of tidal current turbine, a new concept for assessing tidal current energy is introduced with three parameters: total operating time, dispersion of operating time, and mean operating time of tidal current turbine. The operating efficiency of tidal current turbine at three locations around radial submarine sand ridges was taken as examples for comparison, determining suitable sites for development of tidal current farm.
Some Convergence Theorems for Contractive Type Mappings inCAT(0) Spaces
Authors: Kim Kyung Soo
Published: November 2013

We establish theorems of strong convergence, for the Ishikawa-type (or two step;cf. Ishikawa, 1974) iteration scheme, to a fixed point of a uniformlyL-Lipschitzian asymptotically demicontractive mapping and a uniformlyL-Lipschitzian hemicontractive mapping inCAT(0) space. Moreover, we will propose some open problems.
Robust Adaptive PID Control of Robot Manipulator with Bounded Disturbances
Authors: Xu Jian , Qiao Lei
Published: November 2013

To solve the strong nonlinearity and coupling problems in robot manipulator control, two novel robust adaptive PID control schemes are proposed in this paper with known or unknown upper bound of the external disturbances. Invoking the two proposed controllers, the unknown bounded external disturbances can be compensated and the global asymptotical stability with respect to the manipulator positions and velocities is able to be guaranteed. As compared with the existing adaptive PD control methods, the designed control laws can enlarge the tolerable external disturbances, enhance the accuracy in finite-time trajectory tracking control, and improve the dynamic performance of the manipulator systems. The stability and convergence properties of the closed-loop system are analytically proved using Lyapunov stability theory and Barbalat’s lemma. Simulations are performed for a planner manipulator with two rotary degrees of freedom to illustrate the viability and the advantages of the proposed controllers.
Evaluation of Anxiolytic-Like Effect of Aqueous Extract ofAsparagusStem in Mice
Authors: Cheng Long , Pan Guo-feng , Sun Xiao-bo , Huang Yun-xiang , Peng You-shun , Zhou Lin-yan
Published: November 2013

There are few studies on the neuropharmacological properties of asparagus, which was applied in Chinese traditional medicine as a tonic and heat-clearing agent. The present study was designed to investigate the anxiolytic-like activity of the aqueous extract of asparagus stem (AEAS) using elevated plus maze (EPM) and Vogel conflict tests (VCT) in mice. AEAS significantly increased the percentage of time spent in open arms in EPM, when compared with control group. In the Vogel conflict drinking test, the numbers of punished licks increased to 177% and 174% by the treatment of AEAS at the doses of 1.5 and 3.0 g/kg (250 and 500 mg sarsasapogenin per kilogram of body weight), compared with control group. The serum cortisol level decreased significantly, at the same time. In conclusion, these findings indicated that the aqueous extract of asparagus stem exhibited a strong anxiolytic-like effect at dose of 1.5 and 3.0 g/kg (250 and 500 mg sarsasapogenin per kilogram of body weight) in experimental models of anxiety and may be considered an alternative approach for the management of anxiety disorder.
A Note on the Square Roots of a Class of Circulant Matrices
Authors: Zhang Ying , Zhang Huisheng , Chen Guoyan
Published: November 2013

We prove that anyk-circulant matrix and any even order skewk-circulant matrix are diagonalizable for anyk∈ℂ. Then, we propose two algorithms for computing the square roots of thek-circulant matrix and the skewk-circulant matrix, respectively. In particular, we show that the square roots of thek-circulant matrix are stillk-circulant matrices. Both the theoretical analysis and the numerical experiments show that our algorithms are faster than the standard Schur method.
A Multiplier Theorem for Herz-Type Hardy Spaces Associated with the Dunkl Transform
Authors: Gasmi A.
Published: November 2013

The main purpose of this paper is to establish a Hörmander multiplier theorem for Herz-type Hardy spaces associated with the Dunkl transform.
Control Design for Discrete-Time Fuzzy Systems with Disturbance Inputs via Delta Operator Approach
Authors: Zhou Qi , Gao Yabin , Li Hongyi , Karimi Hamid Reza
Published: November 2013

This paper is concerned with the problem of passive control design for discrete-time Takagi-Sugeno (T-S) fuzzy systems with time delay and disturbance input via delta operator approach. The discrete-time passive performance index is established in this paper for the control design problem. By constructing a new type ofLyapunov-Krasovskii function (LKF) in delta domain, and utilizing some fuzzy weighing matrices, a new passive performance condition is proposed for the system under consideration. Based on the condition, a state-feedback passive controller is designed to guarantee that the resulting closed-loop system is very-strictly passive. The existence conditions of the controller can be expressed by linear matrix inequalities (LMIs). Finally, a numerical example is provided to demonstrate the feasibility and effectiveness of the proposed method.
A Collaborative Optimization Model for Ground Taxi Based on Aircraft Priority
Authors: Jiang Yu , Liao Zhihua , Zhang Honghai
Published: November 2013

Large hub airports have gradually become the “bottleneck” of the air transport network. To alleviate the “bottleneck” effect, optimizing the taxi scheduling is one of the solutions. This paper establishes a scheduling optimization model by introducing priority of aircraft under collaborative decision-making mechanism, and a genetic algorithm is designed to verify the scheduling model by simulating. Optimization results show that the reliability of the model and the adjusted genetic algorithm have a high efficiency. The taxiing time decreases by 2.26% when compared with an empirical method and the flights with higher priorities are assigned better taxi routes. It has great significance in reducing flight delays and cost of operation.
Real-Time Dry Beach Length Monitoring for Tailings Dams Based on Visual Measurement
Authors: Hu Jun , Hu Shan , Kang Fei , Zhang Jianhua
Published: November 2013

The length of dry beach is an important factor that influences the safety of tailings dams. However, there still is no accurate and reliable method that can conveniently measure the length of dry beach. In this paper, the authors focus on developing a novel method for dry beach length determination. The proposed method can effectively measure the dry beach length through an ordinary camera and four marking rods placed on the dry beach. Experimental results show that the proposed method can conveniently measure the dry beach length with high accuracy, and therefore it can be adopted as an effective method in tailings dam real-time health monitoring.
Effects of Pretreatment with a Combination of Melatonin and Electroacupuncture in a Rat Model of Transient Focal Cerebral Ischemia
Authors: Liu Lingguang , Cheung R. T. F.
Published: November 2013

Both melatonin and electroacupuncture (EA) have been suggested to be effective treatments against stroke. However, it is unknown whether a combination of these two therapies could be beneficial against transient focal cerebral ischemia. The present study investigated the effects of pretreatment of a combination of melatonin and EA in a rat model of transient middle cerebral artery occlusion (MCAO). After pretreatment of melatonin plus EA (MEA), transient MCAO was induced for 90 minutes in male Sprague-Dawley (SD) rats. The neurological deficit score, brain infarct volume, cerebral edema ratio, neuronal inflammation, and apoptosis were evaluated 24 hours after transient MCAO. The expression of related inflammatory and apoptotic mediators in the brain was also investigated. The results showed that MEA improved neurological outcome, reduced brain infarct volume, and inhibited neuronal inflammation as well as apoptosis 24 hours after transient MCAO. The beneficial effects may derive from downregulation of proinflammatory and proapoptotic mediators and upregulation of antiapoptotic mediators. Thus, these results suggest a preventive effect of pretreatment of MEA on transient focal cerebral ischemia.
Optimal Investment and Consumption Decisions under the Constant Elasticity of Variance Model
Authors: Chang Hao , Rong Xi-min , Zhao Hui , Zhang Chu-bing
Published: November 2013

We consider an investment and consumption problem under the constant elasticity of variance (CEV) model, which is an extension of the original Merton’s problem. In the proposed model, stock price dynamics is assumed to follow a CEV model and our goal is to maximize the expected discounted utility of consumption and terminal wealth. Firstly, we apply dynamic programming principle to obtain the Hamilton-Jacobi-Bellman (HJB) equation for the value function. Secondly, we choose power utility and logarithm utility for our analysis and apply variable change technique to obtain the closed-form solutions to the optimal investment and consumption strategies. Finally, we provide a numerical example to illustrate the effect of market parameters on the optimal investment and consumption strategies.
What Proportion of Chronic Obstructive Pulmonary Disease Outpatients Is Eligible for Inclusion in Randomized Clinical Trials?
Authors: Scichilone Nicola , Basile Marco , Battaglia Salvatore , Bellia Vincenzo
Published: November 2013

Background and Objective: We aimed to explore to what extent an unselected population of chronic obstructive pulmonary disease (COPD) outpatients would be eligible for inclusion in randomized clinical trials (RCTs). Methods: Retrospective analysis of the clinical records of outpatient subjects with an ascertained diagnosis of COPD. COPD outpatients were assessed against the following inclusion criteria: 40 < age < 80 years, current or former smokers, forced expiratory volume in the first second (FEV1) <70% predicted, no long-term oxygen therapy, no other concomitant lung diseases and absence of major extrapulmonary comorbidities. The study consisted of 2 phases; in phase 1, the criteria for inclusion in RCTs on COPD were selected, and in phase 2, the above criteria were applied to an unselected outpatient COPD population. Results: A total of 578 subjects (83% of the whole group) failed at least one of the inclusion criteria. Lung diseases other than COPD (occurring in 30% of our population, mostly bronchiectasis), long-term oxygen therapy (31%), FEV1 (19%), age (14%) and extrapulmonary comorbidities such as cognitive impairment (14%), arrhythmias (17%) and congestive heart disease (13%) would have been the most frequent causes for exclusion from RCTs. Conclusions: In real-life settings, more than 80% of COPD subjects are currently treated by protocols based on results of RCTs for which they would not have been eligible. We encourage a more extensive use of pragmatic trials in COPD to better modulate the application of results of RCTs to patients encountered in daily practice.
Anti-Apoptotic Pathways in Bone Marrow and Megakaryocytes in Myeloproliferative Neoplasia
Authors: Koopmans Suzanne M. , Schouten Harry C. , van Marion Arienne M.W.
Published: November 2013

Objective: Proliferative activity contributes to bone marrow cellularity in myeloproliferative neoplasia (MPN). Megakaryocytes are the most important cells in MPN bone marrow pathology. JAK2V617F mutation constitutively activates JAK2, pErk (phosphorylating extracellular signal-regulated kinase) and PI3K (phosphatidylinositol 3-kinase)-Akt signaling. Erk is involved in megakaryocyte differentiation, PI3K-Akt inhibits megakaryocyte apoptosis via Bcl-xL and two downstream effectors (p70S6k and Bnip3). Immunohistochemic expression of phosphorylated Erk, Akt, p70S6k and Bnip3 was studied along with microvessel density (MVD) in MPN bone marrow and megakaryocytes. Methods: 36 essential thrombocythemia (ET), 25 polycythemia vera and 45 primary myelofibrosis patients were analyzed for pErk, pAkt, Bnip3, p70S6k and MVD expression by immunostaining bone marrow biopsy sections followed by automated image analysis. JAK2V617F was analyzed through real-time PCR in blood samples. Results: pErk and pAkt were significantly higher expressed in MPN megakaryocytes, mainly in ET patients, compared to controls. Bnip3 was higher expressed in bone marrow of control patients and in MPN megakaryocytes. Mainly in ET patients, MPN megakaryocytes showed higher p70S6k expression compared to controls. Conclusion: Increased bone marrow cellularity in MPN patients might be influenced by increased pErk, pAkt and decreased Bnip3 expression. A dominant role for megakaryocytes in ET patients was shown. Increased amounts of megakaryocytes in MPN patients can be due to increased pAkt and p70S6k.
Impact of Stroke Care Unit on Patient Outcomes in a Community Hospital
Authors: Tamm Alexander , Siddiqui Muzaffar , Shuaib Ashfaq , Butcher Ken , Jassal Rajive , Muratoglu Mikael , Buck Brian H.
Published: November 2013

Background and Purpose—

Geographically distinct multidisciplinary stroke care units (SCUs) have been shown by systematic reviews to have superior patient outcomes compared with conventional care in general medical wards. However, the effectiveness of SCUs in smaller North American community hospitals is less well defined. The objective of this study was to determine the impact of establishing a specialized SCU at a community hospital on patient outcomes.

Methods—

This is a retrospective cohort study of 805 patients with stroke admitted to 2 community hospitals in Edmonton, Canada, from 2003 to 2009 using an administrative database. Stroke was identified by
International Classification of Disease, 10th Edition
, codes. One of the community hospitals established a SCU on January 1, 2007. This date was used to subdivide the patient population into 2 cohorts: phase 1 from 2003 to 2006 and phase 2 from 2007 to 2009. Outcomes measured were mortality, discharge disposition, length of stay, and complications and were adjusted for age, sex, and medical comorbidities.

Results—

Patient mortality decreased significantly from 17.1% to 8.3% (adjusted odds ratio [OR], 0.54; 95% confidence interval [CI], 0.31–0.95) after SCU implementation, whereas it remained ≈19% at the control hospital. SCU also increased the odds that patients would be discharged home independently (adjusted OR, 2.17; 95% CI, 1.49–3.15;
P
<0.001] without increasing length of stay.

Conclusions—

Establishing a SCU in a community hospital not only increases the survival of stroke patients, but also the proportion of patients discharged home to live independently. The benefits of SCU reported in larger tertiary centers extend to smaller community hospitals with more limited resources.
Quality of Care and Outcomes for In-Hospital Ischemic Stroke
Authors: Cumbler Ethan , Wald Heidi , Bhatt Deepak L. , Cox Margueritte , Xian Ying , Reeves Mathew , Smith Eric E. , Schwamm Lee , Fonarow Gregg C.
Published: November 2013

Background and Purpose—

Analysis of quality of care for in-hospital stroke has not been previously performed at the national level. This study compares patient characteristics, process measures of quality, and outcomes for in-hospital strokes with those for community-onset strokes in a national cohort.

Methods—

We performed a retrospective cohort study of the Get With The Guidelines-Stroke (GWTG-Stroke) database of The American Heart Association from January 2006 to April 2012, using data from 1280 sites that reported ≥1 in-hospital stroke. Patient characteristics, comorbid illnesses, medications, quality of care measures, and outcomes were analyzed for 21 349 in-hospital ischemic strokes compared with 928 885 community-onset ischemic strokes.

Results—

Patients with in-hospital stroke had more thromboembolic risk factors, including atrial fibrillation, prosthetic heart valves, carotid stenosis, and heart failure (
P
<0.0001), and experienced more severe strokes (median National Institutes of Health Stroke Score 9.0 versus 4.0;
P
<0.0001). Using GWTG-Stroke achievement measures, the proportion of patients with defect-free care was lower for in-hospital strokes (60.8% versus 82.0%;
P
<0.0001). After accounting for patient and hospital characteristics, patients with in-hospital strokes were less likely to be discharged home (adjusted odds ratio 0.37; 95% confidence intervals [0.35–0.39]) or be able to ambulate independently at discharge (adjusted odds ratio 0.42; 95% confidence intervals [0.39–0.45]). In-hospital mortality was higher for in-hospital stroke (adjusted odds ratio 2.72; 95% confidence intervals [2.57–2.88]).

Conclusions—

Compared with community-onset ischemic stroke, patients with in-hospital stroke experienced more severe strokes, received lower adherence to process-based quality measures, and had worse outcomes. These findings suggest there is an important opportunity for targeted quality improvement efforts for patients with in-hospital stroke.
Redescription of Alatina alata (Reynaud, 1830) (Cnidaria: Cubozoa) from Bonaire, Dutch Caribbean
Authors: LEWIS CHERYL , BENTLAGE BASTIAN , YANAGIHARA ANGEL , GILLAN WILLIAM , BLERK JOHAN VAN , KEIL DANIEL P. , BELY ALEXANDRA E. , COLLINS ALLEN G.
Published: November 2013

Here we establish a neotype for Alatina alata (Reynaud, 1830) from the Dutch Caribbean island of Bonaire. The species was originally described one hundred and eighty three years ago as Carybdea alata in La Centurie Zoologique—a monograph published by René Primevère Lesson during the age of worldwide scientific exploration. While monitoring monthly reproductive swarms of A. alata medusae in Bonaire, we documented the ecology and sexual reproduction of this cubozoan species. Examination of forty six A. alata specimens and additional archived multimedia material in the collections of the National Museum of Natural History, Washington, DC revealed that A. alata is found at depths ranging from surface waters to 675 m. Additional studies have reported it at depths of up to 1607 m in the tropical and subtropical Atlantic Ocean. Herein, we resolve the taxonomic confusion long associated with A. alata due to a lack of detail in the original description and conflicting statements in the scientific literature. A new cubozoan character, the velarial lappet, is described for this taxon. The complete description provided here serves to stabilize the taxonomy of the second oldest box jellyfish species, and provide a thorough redescription of the species.
Adrenal adenoma and metastasis from clear cell renal cell carcinoma: can they be differentiated using standard MR techniques?
Authors: Woo Sungmin , Cho Jeong Yeon , Kim Sang Youn , Kim Seung Hyup
Published: November 2013

Background

Chemical-shift magnetic resonance imaging (MRI) has been known to successfully differentiate adenomas from metastases. However, there has been concern that metastasis from extra-adrenal primary malignancies which contain high lipid content such as clear cell renal cell carcinoma (RCC) could mimic adrenal adenomas.

Purpose

To evaluate the ability of MR to differentiate adrenal adenoma from metastasis using chemical-shift imaging and MR feature analysis in patients with clear cell RCC.

Material and Methods

This study was institutional review board-approved; informed consent was waived. Eleven patients with 13 metastases and 13 patients with 15 adrenal adenomas in patients with clear cell RCC for evaluation of an adrenal mass underwent MR. Signal intensity on in- and opposed-phases, signal intensity index (SII), size, T2 SI, cystic change, necrosis, and hemorrhage were evaluated. Statistical analyses included Student t-test and Fisher exact test. If available, precontrast CT attenuation of the adrenal adenomas was measured. SII was correlated with attenuation using Pearson correlation coefficient.

Results

Mean size of adenomas was smaller than that of metastases ( P < 0.002). Mean SII of adenomas (45.0% ± 24.6) was significantly greater than that of metastases (6.6% ± 4.7; P < 0.001). With a threshold of 16.5% for SII, the sensitivity, specificity, and accuracy for adenomas were 80%, 100%, and 89.2%, respectively. All six lipid-rich adenomas were diagnosed as adrenal adenoma. Three of eight (37.5%) lipid-poor adenomas were misdiagnosed as metastases. While up to 53.8% (7/13) of the metastases demonstrated cystic change, necrosis, or hemorrhage, only one (6.7%) adenoma exhibited cystic change or necrosis ( P < 0.05 for all). Precontrast attenuation and SII were significantly correlated: r = –0.810 ( P < 0.001).

Conclusion

In patients with clear cell RCC who underwent MR for adrenal masses, SII and MR features such as cystic change, necrosis, and hemorrhage were helpful in differentiating adenomas from metastases.
Becoming researchers: A narrative study of Chinese university EFL teachers’ research practice and their professional identity construction
Authors: Xu Yueting
Published: November 2013

This article reports on a narrative study of university EFL (English as a foreign language) teachers’ research practices and their identity construction as researchers in China. Drawing upon data from narrative frames among 104 teachers and in-depth interviews with four teachers, the study reveals that teachers’ increased research engagement, as well as mixed attitudes towards and external drives for research, are mediated by their mixed contexts of supporting policies and practical constraints. It also recounts four scenarios of teachers’ identity construction as researchers and explores the reasons why their identities as researchers are more or less fragmented at different times, which may be attributed to academic competence signaled by research interests and publications, institutional and peer support in the workplace, and the professional life cycles in which they are involved. It concludes with implications for promoting research and teachers’ becoming researchers as paths for empowerment and professional excellence through joint efforts from university administrators, mentors, teacher educators and teachers.
Diverse T-cell responses characterize the different manifestations of cutaneous graft-versus-host disease
Authors: Brüggen Marie-Charlotte , Klein Irene , Greinix Hildegard , Bauer Wolfgang , Kuzmina Zoya , Rabitsch Werner , Kalhs Peter , Petzelbauer Peter , Knobler Robert , Stingl Georg , Stary Georg
Published: November 2013

Key Points

Distinct T-cell patterns characterize the acute and chronic forms of cutaneous GVHD. Increased TSLP expression is an indicator of acute cutaneous GVHD development.
Reconciliation-based detection of co-evolving gene families
Authors: Chan Yao-ban , Ranwez Vincent , Scornavacca Celine
Published: November 2013

Background

Genes located in the same chromosome region share common evolutionary events more often than other genes (e.g. a segmental duplication of this region). Their evolution may also be related if they are involved in the same protein complex or biological process. Identifying co-evolving genes can thus shed light on ancestral genome structures and functional gene interactions.

Results

We devise a simple, fast and accurate probability method based on species tree-gene tree reconciliations to detect when two gene families have co-evolved. Our method observes the number and location of predicted macro-evolutionary events, and estimates the probability of having the observed number of common events by chance.

Conclusions

Simulation studies confirm that our method effectively identifies co-evolving families. This opens numerous perspectives on genome-scale analysis where this method could be used to pinpoint co-evolving gene families and thus help to unravel ancestral genome arrangements or undocumented gene interactions.
TTG2-regulated development is related to expression of putative AUXIN RESPONSE FACTOR genes in tobacco
Authors: Zhu Qian , Li Baoyan , Mu Shuyuan , Han Bing , Cui Runzhi , Xu Manyu , You Zhenzhen , Dong Hansong
Published: November 2013

Background

The phytohormone auxin mediates a stunning array of plant development through the functions of AUXIN RESPONSE FACTORs (ARFs), which belong to transcription factors and are present as a protein family comprising 10–43 members so far identified in different plant species. Plant development is also subject to regulation by TRANSPARENT TESTA GLABRA (TTG) proteins, such as NtTTG2 that we recently characterized in tobacco Nicotiana tabacum. To find the functional linkage between TTG and auxin in the regulation of plant development, we performed de novo assembly of the tobacco transcriptome to identify candidates of NtTTG2-regulated ARF genes.

Results

The role of NtTTG2 in tobacco growth and development was studied by analyzing the biological effects of gene silencing and overexpression. The NtTTG2 gene silencing causes repressive effects on vegetative growth, floral anthocyanin synthesis, flower colorization, and seed production. By contrast, the plant growth and development processes are promoted by NtTTG2 overexpression. The growth/developmental function of NtTTG2 associates with differential expression of putative ARF genes identified by de novo assembly of the tobacco transcriptome. The transcriptome contains a total of 54,906 unigenes, including 30,124 unigenes (54.86%) with annotated functions and at least 8,024 unigenes (14.61%) assigned to plant growth and development. The transcriptome also contains 455 unigenes (0.83%) related to auxin responses, including 40 putative ARF genes. Based on quantitative analyses, the expression of the putative genes is either promoted or inhibited by NtTTG2.

Conclusions

The biological effects of the NtTTG2 gene silencing and overexpression suggest that NtTTG2 is an essential regulator of growth and development in tobacco. The effects of the altered NtTTG2 expression on expression levels of putative ARF genes identified in the transcriptome suggest that NtTTG2 functions in relation to ARF transcription factors.