bluuebunny/crossref_metadata_2025_split huggingface dataset:
How we make donors feel: the relationship between premium benefit level and donor identity esteem
Authors: Sargeant Adrian , Shang Jen 
Published: April 2012

Previous studies on promotions have tended to focus on the benefit to the organization of using different promotional benefit levels to incentivize purchase. By contrast, we focus on how perceptions of different benefit levels make individuals feel. We focus on the context of NPR membership where a station uses promotional premiums to incentivize giving to its annual fund. Employing a field survey of 25 895 donors, we find that premium benefit level is positively correlated with the importance of donor identity and negatively correlated with the private donor esteem associated with the organization.Copyright © 2012 John Wiley & Sons, Ltd.
Morphology and properties of biodegradable and biosourced polylactide blends with poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate)
Authors: Han Lijing , Han Changyu , Zhang Huiliang , Chen Shan , Dong Lisong 
Published: April 2012

AbstractBiodegradable polymer blends based on biosourced polymers, namely polylactide (PLA) and poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) (P(3HB‐co‐4HB)), were prepared by melt compounding. The effects of P(3HB‐co‐4HB) on the miscibility, phase morphology, thermal behavior, mechanical properties, and biodegradability of PLA/P(3HB‐co‐4HB) blends were investigated. The blend was an immiscible system with the P(3HB‐co‐4HB) domains evenly dispersed in the PLA matrix. However, the Tg of P(3HB‐co‐4HB) component in the blends decreased compared with neat P(3HB‐co‐4HB), which might be attributed to that the presence of the phase interface between PLA and P(3HB‐co‐4HB) resulted in enhanced chain mobility near interface. The addition of P(3HB‐co‐4HB) enhanced the cold crystallization of PLA in the blends due to the nucleation enhancement of PLA caused by the enhanced chain mobility near the phase interface between PLA and P(3HB‐co‐4HB) in the immiscible blends. With the increase in P(3HB‐co‐4HB) content, the blends showed decreased tensile strength and modulus; however, the elongation at beak was increased significantly, indicating that the inherent brittlement of PLA was improved by adding P(3HB‐co‐4HB). The interesting aspect was that the biodegradability of PLA is significantly enhanced after blends preparation. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Relationship of first‐trimester uterine artery Doppler to late stillbirth
Authors: Iacovella C. , Franchi M. , Egbor M. , Bhide A. , Thilaganathan B. 
Published: April 2012

ABSTRACTObjectiveThe aim of this study was to investigate if increased first‐trimester uterine artery Doppler resistance indices (RI) are related to stillbirth.MethodUterine artery Doppler indices were assessed prospectively during a routine first‐trimester ultrasound scan. Patients were categorised as having a high uterine artery mean Doppler RI if the index was above the 90th centile for gestation. Stillbirth outcomes were ascertained from a mandatory national register of pregnancy losses.ResultsHigh RI uterine artery Doppler (>90th centile) was an independent risk factor for late (≥34 weeks) but not early stillbirth, with a hazard ratio of 2.61 (95% CI 1.13–6.03). The inclusion of uterine artery Doppler indices into Cox proportional hazard model negated the influence of conventional risk factors for stillbirth, such as parity, maternal age and body mass index (BMI), but not Afro‐Caribbean ethnicity or smoking.ConclusionHigh first‐trimester uterine artery Doppler RI is associated with late stillbirth after 34 weeks' gestation. This association supersedes those of conventional risk factors such as maternal age, parity and BMI, implying that these factors result in an increased risk of stillbirth by causing placental dysfunction. © 2012 John Wiley & Sons, Ltd.
Sphenoidal fontanelle area measurement on rendered three‐dimensional ultrasound
Authors: Ioannou Christos , Sarris Ippokratis , Javaid Muhammad K. , Papageorghiou Aris T. 
Published: April 2012

ABSTRACTObjectiveRendered three‐dimensional images of the fetal cranial vault permit the identification of sutures and measurement of the fontanelle surface area. The objective of this study was to establish the feasibility and repeatability of sphenoidal fontanelle area measurement.MethodHead volumes were obtained using the biparietal diameter as the reference plane. These were displayed with maximum rendering and the surface area of the sphenoidal fontanelle was measured by one operator. Feasibility was expressed as the percentage of scans with a successful measurement at different gestational ages. Repeatability was expressed as coefficient of variation (CV), intraclass correlation coefficient (ICC) and Bland–Altman plots.ResultsThirty women underwent 141 scans. Feasibility of sphenoidal fontanelle measurement is over 90% before 26 weeks, but drops gradually thereafter and becomes 0% at 34 weeks. Intraobserver repeatability of measurement on the same scan image demonstrated CV = 17.5% and ICC = 0.883; however, when measuring a newly acquired volume, the repeatability is poor, CV = 30.7% and ICC = 0.649.ConclusionAlthough it is feasible to visualize the sphenoidal fontanelle on rendered three dimensions, its surface area measurement is not reliable for clinical use. There is potential to overestimate repeatability when remeasuring the same volume. © 2012 John Wiley & Sons, Ltd.
Maternal serum human chorionic gonadotropin and pregnancy‐associated plasma protein‐A in pregnancies with fetal homozygous α‐thalassemia‐1 disease
Authors: Tongprasert Fuanglada , Wanapirak Chanane , Tongsong Theera 
Published: April 2012

ABSTRACTObjectiveTo compare the levels of maternal serum free β‐hCG and PAPP‐A between pregnancies with fetal homozygous α‐thalassemia‐1 disease and unaffected pregnancies.Materials and MethodsOne hundred and forty eight pregnancies at risk for fetal homozygous α‐thalassemia‐1 disease scheduled for cordocentesis at 18 to 22 weeks were recruited into the study. Maternal serum free β‐hCG and PAPP‐A concentrations were measured before cordocentesis, and the final fetal diagnosis of homozygous α‐thalassemia‐1 disease was based on fetal Hb typing using high‐performance liquid chromatography.ResultsMaternal serum concentration of free β‐hCG was significantly higher in women with fetal homozygous α‐thalassemia‐1 disease than those with unaffected fetuses (P = 0.018), whereas the concentrations of PAPP‐A was not significantly different (P = 0.184). The median MoM of free β‐hCG in the affected group was 1.38 MoM and in the unaffected group was 0.88 MoM (P = 0.020).ConclusionAt midpregnancy, maternal serum free β‐hCG levels are significantly higher in pregnancies with fetal homozygous α‐thalassemia‐1 disease, signifying that the disease could be a confounder for interpretation free β‐hCG level in Down syndrome screening program. Nevertheless PAPP‐A level seems to be similar in both groups. © 2012 John Wiley & Sons, Ltd.
Curing behavior of Azo‐containing twin liquid crystalline epoxy resins with anhydride
Authors: Zhou Dewen , Lu Mangeng , Liang Liyan , Shen Tengfei , Xiao Wanping 
Published: April 2012

AbstractA series of novel azo‐containing twin liquid crystalline (LC) epoxy monomers were cured with anhydrides without extra catalyst, and the curing kinetics was investigated by non‐isothermal differential scanning calorimetry (DSC) technique. The results showed that the effect of phase behavior on activation energy (Ea) was enormous, which increased first and then decreased quickly with the curing reaction processing. The chemical kinetic control and diffusion‐control mechanisms dominate the curing together, which gives large values of Ea. Azo group also served as a catalyst to accelerate the curing reaction. The curing mechanism was confirmed by the UV–Vis spectra of azo‐doped curing system in which the absorbance values at 366 nm and 475 nm changed with the curing reaction processing. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
The effect of molecular structure of polypropylene on stretchability for biaxially oriented film
Authors: Tamura Satoshi , Kuramoto Itaru , Kanai Toshitaka 
Published: April 2012

AbstractBiaxially oriented polypropylene films are widely used for food packaging and industrial films. Recently, machine speed has been increasing in order to obtain higher production rate, and film thickness has become thinner to reduce the environmental load. The customers' requirements for better production ability and thinner films have been becoming more demanding, but their demands are not always met because of lack of film stretchability in the final product. To meet the demands, research on stretchability has been conducted with the goal of finding the optimum polypropylene molecular structure for developing a new product by analyzing stretching force–strain data using a table tenter, which was thought to be the parameter of stretchability. It was found that low crystallinity and wide molecular weight distribution were effective in improving the stretchability from the table tenter test. By running the test with a sequential and biaxially oriented stretching machine, it was verified that samples produced by the above designed polymer indicated good thickness uniformity, which was considered to be the barometer of stretchability. Furthermore, it was concluded that analyzing the stretching force–strain data obtained from a table tenter is a good method to predict machine speed and film thickness. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Material deformation and fatigue behavior characterization for elastomeric component life predictions
Authors: Zarrin‐Ghalami Touhid , Fatemi Ali 
Published: April 2012

AbstractFailure analysis and prediction of fatigue life of elastomers are important issues due to wide usage of elastomeric components in many applications. Material deformation and fatigue characterization including both crack nucleation and crack growth are typically required for such analysis and predictions. This article discusses relevant material deformation properties obtained from experiments conducted under stress states of simple tension and planar tension. Cyclic transient behavior including Mullin's effect is also discussed. Then, fatigue crack initiation approach and experimental procedure and obtained data are discussed including modeling of the R ratio effect. Finally, based on the fracture mechanics approach, fatigue crack growth test procedure and properties are presented, including a model for R‐ratio effect. It is also shown that using the crack growth approach as a total fatigue life predictor gives reasonable results, as compared with the crack nucleation approach. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
Convex Geometry for the Morphological Modeling and Characterization of Crystal Shapes
Authors: Reinhold Alexander , Briesen Heiko 
Published: April 2012

AbstractTo characterize crystals and other particles not only with respect to their size but also to their shape there has been increasing interest over the last decade. Though there are several studies on the geometric problems for single crystals and studies using morphological population balance equations for specific cases there is a lack of a systematic way to construct models for the growth of crystal populations with arbitrary shape. This is due to the geometrical complexity. The aim of this work is to exploit mathematical theories in the area of convex geometry to overcome this deficiency. By introducing an algebra for convex bodies, any convex crystal shape can be decomposed into a set of simple shapes called structuring elements. The decomposition is a linear combination from which generic equations for the calculation of any measure, like volume, surface area or mean diameter, can be easily derived. Importantly, all the required parameters for these measure calculations can be calculated a priori to any dynamic simulation. Ultimately, this allows the generic construction of morphological population balances to model crystal growth. Additionally, the combinatorial complexity is explored with respect to the computational effort. Although the concepts are developed for faceted crystals only, the framework may apply to a much broader class of convex particles.
Particle Size Management Studies on Spherical 3‐Nitro‐1,2,4‐triazol‐5‐one
Authors: Vijayalakshmi Ramavat , Radhakrishnan Sarangapani , Rajendra Patil S. , Girish Gore M. , Arun Sikder K. 
Published: April 2012

AbstractParticle shape and size of an energetic material play a vital role in achieving explosive formulations with optimal performance that decides the realization of high bulk and theoretical maximum density (TMD) and mix fluidity during their processing. 3‐Nitro‐1, 2, 4‐triazol‐5‐one (NTO) is an insensitive thermally stable high explosive and explored as a potential replacement of RDX in explosive formulations. This study investigates the preparation of spherical NTO in NTO: water: 1‐methyl‐2‐pyrolidone ternary system and the particle size management of spherical NTO by cooling crystallization technique. Crystallization operation variables like cooling rate, agitator configuration, speed, etc. have been systematically studied to understand their effect on the spheroidization process. Synthesized spherical NTO has been characterized by spectral, thermal and microscopic studies. The study established the process parameters to achieve selective particle size distribution ranging from 10 to 200 μm. Bulk density of the spherical NTO has been determined and correlated with particle size distribution.
Synthesis and Characterization of Carbon Nanotubes Wrapped on Anatase Microparticles
Authors: Barone Pasquale , Barberio Marianna , Oliva Antonino , Bonanno Assunta 
Published: April 2012

AbstractIn this work we present a study of growth and characterization of a composite based on TiO2 (anatase form) and carbon nanotubes (CNT). The composite was prepared by the chemical mix techniques suggested in [1], improved by changing the recipe for what concerns solvent type, sonication and heating time to obtain a greater carbon nanotubes solubility. The prepared samples were characterized by SEM analysis, energy dispersed X‐ray measurements (EDX) and X‐ray photoelectron spectroscopy (XPS). The analysis showed that the sample is formed by a direct contact between CNT and anatase, with CNTs wrapped around anatase micrometer particles. XPS analysis shows the typical lines of TiO2 and CNTs (Ti2p and C1s), without any indication for the Ti‐C chemical bond, instead the detection of the O1s line can be attributed to both bonds, Ti‐O and C‐O. Finally the composite was compared with a similar sample obtained by evaporating Ti on a CNT substrate, as discussed in [2]. The two different techniques produce very different composites, the first one (chemical mix) exhibits a strong contact between CNTs and anatase particles which appear uniformly distributed in the sample, while the other technique (evaporation) shows two separated and superimposed films (titanium dioxide on CNT).
Solution structure studies of monomeric human TIP47/perilipin‐3 reveal a highly extended conformation
Authors: Hynson Robert M. G. , Jeffries Cy M. , Trewhella Jill , Cocklin Simon 
Published: April 2012

AbstractTail‐interacting protein of 47 kDa (TIP47) has two putative functions: lipid biogenesis and mannose 6‐phosphate receptor recycling. Progress in understanding the molecular details of these two functions has been hampered by the lack of structural data on TIP47, with a crystal structure of the C‐terminal domain of the mouse homolog constituting the only structural data in the literature so far. Our studies have first provided a strategy to obtain pure monodisperse preparations of the full‐length TIP47/perilipin‐3 protein, as well as a series of N‐terminal truncation mutants with no exogenous sequences. These constructs have then enabled us to obtain the first structural characterization of the full‐length protein in solution. Our work demonstrates that the N‐terminal region of TIP47/perilipin‐3, in contrast to the largely helical C‐terminal region, is predominantly β‐structure with turns and bends. Moreover, we show that full‐length TIP47/perilipin‐3 adopts an extended conformation in solution, with considerable spatial separation of the N‐ and C‐termini that would likely translate into a separation of functional domains. Proteins 2012;. © 2012 Wiley Periodicals, Inc.
Comparative assessment of QSTR models based on density functional, hartree–fock, AM1, and PM3 methods for acute toxicity of aliphatic compounds toward Vibrio fischeri
Authors: Pandith Altaf Hussain , Islam Nasarul 
Published: April 2012

AbstractComparative quantitative‐structure‐toxicity‐relationship models developed using various quantum chemical descriptors calculated at semiempirical (AM1, PM3), Hartree–Fock and density functional theory (DFT) (B3LYP) methods, are compared for predicting the toxicity (pIGC50) of 69 aliphatic compounds toward Vibrio fischeri. The multiple linear regression equations, which can assist in modeling toxicity of these compounds, are developed using molecular descriptor, log P (1‐octanol/water partition coefficient) in conjunction with two quantum chemical descriptors, electrophilicity index (ω) and energy of the lowest unoccupied molecular orbital (ELUMO). The calculated toxicity values (PIGC50) based on the model equations are compared with the experimental data. In general, the stepwise model regression equations based on quantum chemical descriptor ω in combination with molecular descriptor log P, calculated at DFT(B3LYP) with 6‐311G (d,p) and DGDVZP basis sets show better agreement with the experimental data. The electronic origin of the toxicity dependence on descriptors like log P, ω and ELUMO is traced to the cumulative contribution of the lipophilicity and electrophilicity of the chemical moieties to their toxic behavior. © 2012 Wiley Periodicals, Inc.
Non‐orthogonal tool/flange and robot/world calibration
Authors: Ernst Floris , Richter Lars , Matthäus Lars , Martens Volker , Bruder Ralf , Schlaefer Alexander , Schweikard Achim 
Published: April 2012

AbstractBackgroundFor many robot‐assisted medical applications, it is necessary to accurately compute the relation between the robot's coordinate system and the coordinate system of a localisation or tracking device. Today, this is typically carried out using hand‐eye calibration methods like those proposed by Tsai/Lenz or Daniilidis.MethodsWe present a new method for simultaneous tool/flange and robot/world calibration by estimating a solution to the matrix equation AX = YB. It is computed using a least‐squares approach. Because real robots and localisation are all afflicted by errors, our approach allows for non‐orthogonal matrices, partially compensating for imperfect calibration of the robot or localisation device. We also introduce a new method where full robot/world and partial tool/flange calibration is possible by using localisation devices providing less than six degrees of freedom (DOFs).The methods are evaluated on simulation data and on real‐world measurements from optical and magnetical tracking devices, volumetric ultrasound providing 3‐DOF data, and a surface laser scanning device. We compare our methods with two classical approaches: the method by Tsai/Lenz and the method by Daniilidis.ResultsIn all experiments, the new algorithms outperform the classical methods in terms of translational accuracy by up to 80% and perform similarly in terms of rotational accuracy. Additionally, the methods are shown to be stable: the number of calibration stations used has far less influence on calibration quality than for the classical methods.ConclusionOur work shows that the new method can be used for estimating the relationship between the robot's and the localisation device's coordinate systems. The new method can also be used for deficient systems providing only 3‐DOF data, and it can be employed in real‐time scenarios because of its speed. Copyright © 2012 John Wiley & Sons, Ltd.
Adaptive consensus with a virtual leader of multiple agents governed by locally Lipschitz nonlinearity
Authors: Hu Yuebing , Su Housheng , Lam James 
Published: April 2012

SUMMARYThis paper is concerned with the second‐order consensus problem of multi‐agent systems with a virtual leader, where all agents and the virtual leader share the same intrinsic dynamics with a locally Lipschitz condition. It is assumed that only a small fraction of agents in the group are informed about the position and velocity of the virtual leader. A connectivity‐preserving adaptive controller is proposed to ensure the consensus of multi‐agent systems, wherein no information about the nonlinear dynamics is needed. Moreover, it is proved that the consensus can be reached globally with the proposed control strategy if the degree of the nonlinear dynamics is smaller than some analytical value. Numerical simulations are further provided to illustrate the theoretical results. Copyright © 2012 John Wiley & Sons, Ltd.
Computationally efficient simultaneous policy update algorithm for nonlinear H∞ state feedback control with Galerkin's method
Authors: Luo Biao , Wu Huai‐Ning 
Published: April 2012

SUMMARYThe main bottleneck for the application of H∞ control theory on practical nonlinear systems is the need to solve the Hamilton–Jacobi–Isaacs (HJI) equation. The HJI equation is a nonlinear partial differential equation (PDE) that has proven to be impossible to solve analytically, even the approximate solution is still difficult to obtain. In this paper, we propose a simultaneous policy update algorithm (SPUA), in which the nonlinear HJI equation is solved by iteratively solving a sequence of Lyapunov function equations that are linear PDEs. By constructing a fixed point equation, the convergence of the SPUA is established rigorously by proving that it is essentially a Newton's iteration method for finding the fixed point. Subsequently, a computationally efficient SPUA (CESPUA) based on Galerkin's method, is developed to solve Lyapunov function equations in each iterative step of SPUA. The CESPUA is simple for implementation because only one iterative loop is included. Through the simulation studies on three examples, the results demonstrate that the proposed CESPUA is valid and efficient. Copyright © 2012 John Wiley & Sons, Ltd.
Measurement feedback control for a class of feedforward nonlinear systems
Authors: Jo Hyun‐Wook , Choi Ho‐Lim , Lim Jong‐Tae 
Published: April 2012

SUMMARYWe propose a measurement feedback controller for a class of feedforward nonlinear systems under sensor noise. The sensor noise has unknown magnitude, frequency, and phase. Our proposed controller is coupled with a low‐pass filter in such a way that the sensor noise is attenuated. We show that the controlled system results in bounded states whose ultimate bounds are inversely proportional to the minimum frequency of the sensor noise. Our result is further generalized to work in a case where the sensor noise is only required to have a Fourier transform with finite energy. Moreover, if the sensor noise enters only at partial states, depending on the location of the sensor noise, the ultimate bounds of the particular states can be made arbitrarily small via the gain factor of the controller. Copyright © 2012 John Wiley & Sons, Ltd.
Canonical form of para‐Hermitian pencils, generalized spectral factorization, and optimal control over frequency region
Authors: Stefanovski Jovan 
Published: April 2012

SUMMARYWe generalize the J‐spectral factorization of para‐Hermitian proper rational matrix in the case when it has no constant inertia on the imaginary axis. This result and the presented numerical algorithm are based on a canonical form of para‐Hermitian matrix pencils. We apply the new spectral factorization to the optimal control of the proper plant by dynamic measurement feedback over a frequency region. Copyright © 2012 John Wiley & Sons, Ltd.