bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basis set limit computation of dynamic polarizability at near‐resonance region
Authors: Kato Tetsuya , Yokoi Yukina , Sekino Hideo 
Published: May 2012

AbstractWe evaluate dynamic molecular polarizability at near‐resonance region using multiresolution multiwavelet (MRMW) basis set. The results obtained by traditional Gaussian basis sets are compared against the MRMW one. For perpendicular component, d‐aug functions seem to be necessary. Very large Gaussian basis sets beyond d‐aug‐cc‐pvqz can provide the results close to the complete space value obtained by the MRMW even for near‐resonance region. Improvement by enlargement of Gaussian functions is less systematic in the parallel component than in the perpendicular component. The competitiveness of the MRMW method against Gaussian methods in the computational efficiency for property evaluation is also discussed. © 2012 Wiley Periodicals, Inc.
Three‐time scale singular perturbation control and stability analysis for an autonomous helicopter on a platform
Authors: Esteban S. , Gordillo F. , Aracil J. 
Published: May 2012

SUMMARYA three‐time scale singular perturbation control law is designed for a nonlinear helicopter model in vertical flight. The proposed control law is based on time scale decomposition and is able to achieve the desired altitude by selecting a desired angular velocity and the associated collective pitch angle of the blades. The stability of the system is performed by presenting a stability analysis for generic three‐time scale singularly perturbed systems, which allows to construct a composite Lyapunov function for the resultant closed‐loop system by using time scale separation and also providing mathematical expressions for the upper bounds of the singularly perturbed parameters that define the three‐time scale. Numerical results on both, the singular perturbation control strategy and the stability analysis, are also presented for the studied nonlinear highly coupled helicopter model. Copyright © 2012 John Wiley & Sons, Ltd.
Cooperative observers and regulators for discrete‐time multiagent systems
Authors: Hengster‐Movric Kristian , Lewis Frank 
Published: May 2012

SUMMARYThis paper investigates the design of distributed observers for agents with identical linear discrete‐time state‐space dynamics networked on a directed graph interaction topology. The digraph is assumed to have fixed topology and contain a spanning tree. Cooperative observer design guaranteeing convergence of the estimates of all agents to their actual states is proposed. The notion of convergence region for distributed observers on graphs is introduced. It is shown that the proposed cooperative observer design has a robustness property. Application of cooperative observers is made to the synchronization problem. A command trajectory generator and pinning control are employed for synchronizing all the agents to a desired trajectory. Complete knowledge about the agent's state is not assumed. A duality principle is shown for observers and state feedback for distributed discrete‐time systems on graph topologies. Three different observer/controller architectures are proposed for dynamic output feedback regulator design, and they are shown to guarantee convergence of the estimate to the true state and synchronization of all the agents' states to the command state trajectory. This provides design methods for cooperative regulators based on a separation principle. It is shown that the observer convergence region and feedback control synchronizing region for discrete‐time systems are inherently bounded, so that the conditions for observer convergence and state synchronization are stricter than the results for the continuous‐time counterparts. This is in part remedied by using weighting of different feedback coupling gains for every agent. Copyright © 2012 John Wiley & Sons, Ltd.
Real‐time Kalman filtering based on distributed measurements
Authors: Cui Peng , Zhang Huanshui , Lam James , Ma Lifeng 
Published: May 2012

SUMMARYA kind of real‐time Kalman filtering problem is discussed for systems with distributed multichannel measurements. Recursive filters are presented for two cases with correlated and uncorrelated measurement noises. An optimal algorithm is constructed using projection theory in Hilbert space according to a first‐come‐first‐served scheme. An update is generated whenever a new measurement arrives at a central unit. Therefore, the algorithm has the practical advantages of flexibility and the easiness for real‐time implementation. Copyright © 2012 John Wiley & Sons, Ltd.
Invertibility of symmetric random matrices
Authors: Vershynin Roman 
Published: May 2012

AbstractWe study symmetric random matrices H, possibly discrete, with iid above‐diagonal entries. We show that H is singular with probability at most , and . Furthermore, the spectrum of H is delocalized on the optimal scale . These results improve upon a polynomial singularity bound due to Costello, Tao and Vu, and they generalize, up to constant factors, results of Tao and Vu, and Erdös, Schlein and Yau.Copyright © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 44, 135‐182, 2014
Directional spread‐spectrum modulation signal for physical layer security communication applications
Authors: Hong Tao , Song Mao‐zhong , Liu Yu 
Published: May 2012

ABSTRACTIn this paper, we propose a directional spread‐spectrum modulation (DSM) signal transmitted by a switched antenna array for physical layer security communication. The main idea is that the antenna hopping scheme is designed according to a spreading sequence. Fundamental frequency component and all harmonic components generated by antenna hopping are used to form the DSM signal with the characteristic of being directional. This signal is associated with the spreading sequence and the direction of the desired receiver because of DSM signal modulated both in the baseband and the antenna level. In this way, the desired receiver with a single antenna demodulates the receive signal as traditional spread‐spectrum signal, whereas eavesdroppers cannot extract any useful information from the receive signal even if eavesdroppers know the spreading sequence of DSM signal. Finally, simulation results show that the proposed signal offers a more secure transmission method for wireless communication compared with the traditional spread‐spectrum signal. Copyright © 2012 John Wiley & Sons, Ltd.
A more secure and scalable routing protocol for mobile ad hoc networks
Authors: Qabajeh Liana Khamis , Kiah Miss Laiha Mat , Qabajeh Mohammad Moustafa 
Published: May 2012

ABSTRACTAn essential problem in mobile ad hoc networks is finding an efficient and secure route from a source to an intended destination. In this paper, we have proposed a new model of routing protocol named ARANz, which is an extension of the original Authenticated Routing for Ad Hoc Networks (ARAN). ARANz adopts the authentication methods used with ARAN and aims to increase security, achieve robustness and solve the single point of failure and attack problems by introducing multiple local certificate authority servers. Additionally, via dealing with the network as zones and using restricted directional flooding, our new model exhibits better scalability and performance. Through simulation, we evaluated ARANz and compared it with the original ARAN as well as Ad Hoc On‐demand Distance Vector. Simulation results show that ARANz is able to effectively discover secure routes within relatively large networks with large number of mobile nodes, while maintaining the minimum packet routing load. Copyright © 2012 John Wiley & Sons, Ltd.
Firm heterogeneity in growth option value: The role of managerial incentives
Authors: Alessandri Todd M. , Tong Tony W. , Reuer Jeffrey J. 
Published: May 2012

AbstractGrowth option value varies widely across firms. This research explores managerial incentives as a source of firm heterogeneity in growth option value. We argue that when the payoff structure of managerial incentives corresponds to that of growth options, managers will be motivated to pursue actions that increase firms' growth option value, particularly when greater growth opportunities are available in an industry. Results indicate that stock option holdings and managerial stock ownership have a positive effect on growth option value, while short‐term pay has a negative effect. We also find support for a positive interaction effect between equity‐based managerial incentives and industry growth opportunities on growth option value. These findings highlight the critical role of managerial incentives in affecting firms' realization of growth option value. Copyright © 2012 John Wiley & Sons, Ltd.
Bin smoother
Authors: Klemelä Jussi 
Published: May 2012

AbstractBin smoothers, or regressograms, are piecewise constant regression function estimators whose values are averages of the response variable over the sets of a partition of the space of the explanatory variables. First, we review results about bin smoothers whose partition is regular, giving conditions for consistency and for achieving the optimal rate of convergence. Second, we review representative results about bin smoothers whose partition is irregular, again giving conditions for consistency and for achieving the optimal rate of convergence. Third, we give an exposition of recursive partitioning, main examples being greedy partitions and the classification and regression tress (CART) methodology. WIREs Comput Stat 2012 doi: 10.1002/wics.1214This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Classification and Regression Trees (CART)
Statistical and Graphical Methods of Data Analysis > Density Estimation
Statistical and Graphical Methods of Data Analysis > Nonparametric Methods
Evaluating population estimates of mountain goats based on citizen science
Authors: Belt Jami J. , Krausman Paul R. 
Published: May 2012

AbstractCitizen science programs that use trained volunteers may be a cost‐effective method for monitoring wildlife at large scales. However, few studies have compared data collected by volunteers versus biologists. In Glacier National Park (GNP), Montana, USA, we assessed whether citizen science is a useful method to monitor mountain goat (Oreamnos americanus) populations. We compared estimates of mountain goat abundance by volunteers at 32 sites throughout GNP with estimates by biologists and aerial surveys at a subset of 25 and 11 sites, respectively. We used multiple‐observer surveys to calibrate the indices of abundance at each site for observer variation between volunteers and biologists. We used N‐mixture models to obtain estimates of abundance across all sites. Population estimates by citizen scientists overlapped estimates by biologists. Density estimates from aerial surveys were lower than ground estimates. Mean detection probability from multiple‐observer surveys for biologists was significantly higher and less variable than that of volunteers. More frequent site visits balanced out lower detection probability by volunteers and resulted in abundance estimates that were less variable than those of biologists. When large spatial and temporal coverage can be achieved, citizen science can provide mountain goat population estimates that are statistically similar to those of biologists. © 2012 The Wildlife Society.
Simulating carnivore movements: An occupancy–abundance relationship for surveying wolves
Authors: Webb Nathan F. , Merrill Evelyn H. 
Published: May 2012

AbstractWhere carnivore species exist at low densities, are cryptic, and inhabit forested habitats where detection is low, survey approaches commonly rely on observation of tracks. Recent advances in probability sampling for aerial surveys of track networks in snow show promise for improving density estimates, but they are not applicable when continuously following a track network is not possible. Occupancy–abundance modeling is an alternative survey approach for wide‐ranging carnivores, but past models may not be appropriate when using tracks because tracks of one individual or group of individuals may extend across several survey units. We derived an occupancy–abundance relationship by simulating the intersection of wolf (Canis lupus) travel paths and survey grid cells for a range of wolf‐pack densities. Wolf movement paths were simulated using a habitat‐biased, correlated random walk movement model using step lengths and turning angles of 17 Global Positioning System (GPS)‐collared wolves in west‐central Alberta, Canada. We estimated occupancy levels for a range of pack densities found in North America and found that pack density was linearly related to the proportion of occupied survey units. Concurrent movement paths of 5 GPS‐collared wolf packs were used to evaluate the model predictions. While the model overestimated the number of packs by 33%, the difference translated into only 13 wolves across the study area. We discuss improvements for continued development of occupancy surveys as a potential method to determine carnivore abundance where other approaches are not feasible. © 2012 The Wildlife Society.
Systems pharmacology, pharmacogenetics, and clinical trial design in network medicine
Authors: Antman Elliott , Weiss Scott , Loscalzo Joseph 
Published: May 2012

AbstractThe rapidly growing disciplines of systems biology and network science are now poised to meet the fields of clinical medicine and pharmacology. Principles of systems pharmacology can be applied to drug design and, ultimately, testing in human clinical trials. Rather than focusing exclusively on single drug targets, systems pharmacology examines the holistic response of a phenotype‐dependent pathway or pathways to drug perturbation. Knowledge of individual pharmacogenetic profiles further modulates the responses to these drug perturbations, moving the field toward more individualized (‘personalized’) drug development. The speed with which the information required to assess these system responses and their genomic underpinnings is changing and the importance of identifying the optimal drug or drug combinations for maximal benefit and minimal risk require that clinical trial design strategies be adaptable. In this paper, we review the tenets of adaptive clinical trial design as they may apply to an era of expanding knowledge of systems pharmacology and pharmacogenomics, and clinical trail design in network medicine. WIREs Syst Biol Med 2011 DOI: 10.1002/wsbm.1173This article is categorized under:

Physiology > Mammalian Physiology in Health and Disease
Translational, Genomic, and Systems Medicine > Translational Medicine
Tumoral epithelial and stromal expression of SMAD proteins in pancreatic ductal adenocarcinomas
Authors: Handra‐Luca Adriana , Hammel Pascal , Sauvanet Alain , Ruszniewski Philippe , Couvelard Anne 
Published: May 2012

AbstractBackgroundSMAD proteins, intracellular mediators of the transforming growth factor (TGF)‐beta pathway, function within two axes, the SMAD1/5/8 and SMAD2/3, connected to TGF‐beta and bone morphogenetic protein (BMP) ligands. The SMAD proteins of these two axes dimerize with SMAD4 and translocate to the nucleus. SMAD signaling is characterized by a dichotomic functioning, with tumor‐suppressive functions and with loss of normal growth inhibitory responses, depending on the carcinogenesis stage. SMAD proteins also have pro‐tumor effects including abnormal extracellular matrix production. Among tumors, pancreatic cancers harbor SMAD4 inactivation the most frequently and the SMAD proteins are considered to be key factors in pancreatic carcinogenesis.MethodsOur aims were to study the expression patterns of the different types of SMAD proteins in pancreatic ductal adenocarcinomas treated by surgical resection (without neoadjuvant treatment) and their correlations with morphological and clinical characteristics. We examined the immunohistochemical expression of SMAD4, SMAD1/5/8, and SMAD2/3 in 99 pancreatic ductal adenocarcinomas. Antibodies directed against the activated, phosphorylated forms of proteins were used when appropriate (SMAD1/5/8, SMAD2/3). Protein expression in the epithelial tumor cells and in stromal fibroblasts was analyzed with regard to morphological and clinical data.ResultsEpithelial tumor cells showed SMAD1/5/8, SMAD2/3, and, SMAD4 expression in 13, 93, and 45 tumors, respectively, and stromal fibroblast expression in 5, 11, and 22 tumors, respectively. Epithelial SMAD4 was associated with a low, T1 or T2, TNM stage, and with the presence of an abundant stroma (p = 0.05 and <0.01, respectively). Activated stromal fibroblast SMAD2/3 expression was correlated with the presence of a fibrotic focus (p = 0.01), whereas fibroblast SMAD4 was related to a tendency for shorter postsurgical overall survival (p = 0.07). The relationship of stromal, fibroblast SMAD4 to a worse outcome attained statistical significance in the group of patients with T1 and with N1 stage tumors (p < 0.01 and p = 0.04, respectively).ConclusionIn pancreatic ductal adenocarcinomas, SMAD protein expression in epithelial tumor cells or in stromal fibroblasts was related to stromal features and to a shorter postsurgical overall survival. Our results point out that the SMAD proteins play a role in the microenvironment of this highly fibrotic tumor type.
Treatment of Two-Part Proximal Humerus Fractures: Intramedullary Nail Compared to Locked Plating
Authors: Lekic Nikola , Montero Nicole M. , Takemoto Richelle C. , Davidovitch Roy I. , Egol Kenneth A. 
Published: May 2012

Background Two-part proximal humerus fractures are common orthopedic injuries for which surgical intervention is often indicated. Choosing a fixation device remains a topic of debate. Purpose The purpose of this study is to compare two methods of fixation for two-part proximal humerus fractures, locking plate (LP) with screws versus intramedullary nailing (IMN), with respect to alignment, healing, patient outcomes, and complications. To our knowledge, a direct comparison of these two devices in treating two-part proximal humerus fractures has never before been studied. We hope that our results will help surgeons assess the utility of LP versus IMN. Methods A retrospective chart review was performed on 24 cases of displaced two-part surgical neck fractures of the humerus. Twelve shoulders were treated using IMN fixation and 12 others were fixated with LP. Data collected included sociodemographic, operative details, and postoperative care and function. Results Radiographic comparison of fixation demonstrated an average neck-shaft angle of 124° and 120° in the IMN group and LP group, respectively. Adjusted postoperative 6-month follow-up range of motion was 134° of forward elevation in the IMN group and 141 in the LP group. The differences in range of motion and in complication rates were not found to be significant. Conclusions Our results suggest that either LP fixation or IMN fixation for a two-part proximal humerus fracture provides acceptable fixation and results in a similar range of shoulder motion. Although complication rates were low and insignificant between the two groups, a trend toward increased complications in the IMN group is noted.
Steel‐Corrosion Inhibitors Derived from Soybean Oil
Authors: Graiver D. , Dacomba R. , Khawaji M. , Jaros A. , Berglund K. , Narayan R. 
Published: May 2012

AbstractSoybean oil derivatives containing a Schiff‐base (SOS‐B) were prepared and evaluated as microbial corrosion inhibitors against sulfate‐reducing bacteria using the gram‐positive Desulfosporosinus orientis bacteria as a representative bacterium. These SOS‐B compounds were also found to be excellent inhibitors against acidic corrosion of carbon steel. These soybean oil derivatives were prepared by ozonation of soybean oil to yield aldehyde functional intermediates which were then reacted with benzylamine to produce a mixture of imine functional triglycerides and linear compounds. The structure of these soy‐based derivatives was confirmed by FTIR and NMR. It was found that the addition of these SOS‐B compounds to D. orientis culture provided a complete inhibition of this bacterium. Furthermore, almost no corrosion of carbon steel panels was observed when the panels were aged in 2N HCl solution containing 10 ppm of these SOS‐B compounds.
TAL—Template Authoring Language
Authors: Soares Neto Carlos de Salles , Soares Luiz Fernando Gomes , de Souza Clarisse Sieckenius 
Published: May 2012

Abstract
This paper presents TAL (Template Authoring Language), an authoring language for hypermedia document templates. Templates describe document families with structural or semantic similarities among them. TAL supports the description of templates independently of the target hypermedia authoring language. The paper also presents a TAL processor that generates complete hypermedia documents taking as input a template specification in TAL and a data file with the information that makes that document particular in its family.
Orally administered [14C]DPA and [14C]DHA are metabolised differently to [14C]EPA in rats
Authors: Kaur Gunveen , Molero Juan C. , Weisinger Harrison S. , Sinclair Andrew J. 
Published: May 2012

Previous studies have revealed that C20 PUFA are significantly less oxidised to CO2in whole-body studies compared with SFA, MUFA and C18 PUFA. The present study determined the extent to which three long-chain PUFA, namely 20 : 5n-3 EPA, 22 : 5n-3 docosapentaenoic acid (DPA) and 22 : 6n-3 DHA, were catabolised to CO2or, conversely, incorporated into tissue lipids. Rats were administered a single oral dose of 2·5 μCi [1-14C]DPA, [1-14C]EPA, [1-14C]DHA or [1-14C]oleic acid (18 : 1n-9; OA), and were placed in a metabolism chamber for 6 h where exhaled14CO2was trapped and counted for radioactivity. Rats were euthanised after 24 h and tissues were removed for analysis of radioactivity in tissue lipids. The results showed that DPA and DHA were catabolised to CO2significantly less compared with EPA and OA (P< 0·05). The phospholipid (PL) fraction was the most labelled for all threen-3 PUFA compared with OA in all tissues, and there was no difference between C20 and C22n-3 PUFA in the proportion of label in the PL fraction. The DHA and DPA groups showed significantly more label than the EPA group in both skeletal muscle and heart. In the brain and heart tissue, there was significantly less label in the cholesterol fraction from the C22n-3 PUFA group compared with the C20n-3 PUFA group. The higher incorporation of DHA and DPA into the heart and skeletal muscle, compared with EPA, suggests that these C22n-3 PUFA might play an important role in these tissues.
Age, growth and population structure of jumbo flying squid, Dosidicus gigas, off the Costa Rica Dome
Authors: Chen Xinjun , Li Jianhua , Liu Bilin , Chen Yong , Li Gang , Fang Zhou , Tian Siquan 
Published: May 2012

Based on the samples collected in Chinese scientific surveys off the Costa Rica Dome from July to August in 2009, statolith microstructure of the jumbo flying squid, Dosidicus gigas, was analysed for studying their age, growth and population structure. Three typical growth zones (postnuclear, dark and peripheral zones), abnormal increments (checks) and aberrant microstructure (additional centre and additional rings) were found in the statoliths examined. Squid sizes ranged from 205 to 429 mm dorsal mantle length (ML) with ages no more than 10 months for females and 8 months for males. Back-calculated hatching dates were from November 2008 to April 2009. Growth in ML was best described by a linear function for both the sexes, while growth in body weight was best quantified by an exponential function for females and a power curve for males. The maximum absolute daily growth rates and instantaneous growth rate in ML were reached during 181–210 and 151–180 days for females and males, respectively. The Costa Rica Dome and its adjacent waters were considered as a potential spawning ground because of presence of not only high proportion of mature squid but also rhynchoteuthion paralarvae, and high primary productivity from the strong upwelling. This study suggests that D. gigas have complicated intra-specific population structure and large spatial variability in the key life history parameters.