bluuebunny/crossref_metadata_2025 huggingface dataset:
Perspective: Ionomer Research and Applications
Authors: Zhang Longhe , Brostowitz Nicole R. , Cavicchi Kevin A. , Weiss R. A.
Published: December 2013

Ionomers are polymers with bonded ionic species that are used under conditions where the salt groups are in a condensed state. This Feature Article discusses the state of our understanding of ionomers and the historical applications of these nanostructured polymers. It also discusses modern methods for synthesizing new ionomers and describes a number of relatively new applications for ionomers and the potential use of these materials in contemporary technologies, including, shape memory and self‐healing materials and supramolecular polymer systems.
A finite element approach combining a reduced‐order system, Padé approximants, and an adaptive frequency windowing for fast multi‐frequency solution of poro‐acoustic problems
Authors: Rumpler R. , Göransson P. , Deü J.‐F.
Published: December 2013

In this work, a solution strategy is investigated for the resolution of multi‐frequency structural‐acoustic problems including 3D modeling of poroelastic materials. The finite element method is used, together with a combination of a modal‐based reduction of the poroelastic domain and a Padé‐based reconstruction approach. It thus takes advantage of the reduced‐size of the problem while further improving the computational efficiency by limiting the number of frequency resolutions of the full‐sized problem. An adaptive procedure is proposed for the discretization of the frequency range into frequency intervals of reconstructed solution. The validation is presented on a 3D poro‐acoustic example. Copyright © 2013 John Wiley & Sons, Ltd.
A high‐order approach for modelling transient wave propagation problems using the scaled boundary finite element method
Authors: Chen D. , Birk C. , Song C. , Du C.
Published: December 2013

A high‐order time‐domain approach for wave propagation in bounded and unbounded domains is proposed. It is based on the scaled boundary FEM, which excels in modelling unbounded domains and singularities. The dynamic stiffness matrices of bounded and unbounded domains are expressed as continued‐fraction expansions, which leads to accurate results with only about three terms per wavelength. An improved continued‐fraction approach for bounded domains is proposed, which yields numerically more robust time‐domain formulations. The coefficient matrices of the corresponding continued‐fraction expansion are determined recursively. The resulting solution is suitable for systems with many DOFs as it converges over the whole frequency range, even for high orders of expansion. A scheme for coupling the proposed improved high‐order time‐domain formulation for bounded domains with a high‐order transmitting boundary suggested previously is also proposed. In the time‐domain, the coupled model corresponds to equations of motion with symmetric, banded and frequency‐independent coefficient matrices, which can be solved efficiently using standard time‐integration schemes. Numerical examples for modal and time‐domain analysis are presented to demonstrate the increased robustness, efficiency and accuracy of the proposed method. Copyright © 2013 John Wiley & Sons, Ltd.
A direct search approach to optimization for nonlinear model predictive control
Authors: Gibson James D.
Published: December 2013

Nonlinear model predictive control (NMPC) depends on performing a constrained nonlinear optimization, based on predictions of future system behavior, during a sampling interval to determine the control action to be applied to the system during the next time step. The difficulty in designing an optimization procedure to solve a constrained NMPC problem is due to the finite time horizon to which the predictive model is evaluated, the state and control actuator constraints, and sampling interval length. The resulting objective function, which is to be optimized is typically not differentiable. Although there are many commercial, shareware, and open‐source optimization packages available that can perform a nonlinear constrained optimization for most cases, there are NMPC implementations requiring embedded code or that must meet stringent timing requirements that preclude the use of off‐the‐shelf packages. In cases where the predictive model is known, such as aerodynamic or hydrodynamic systems, a direct‐search optimization algorithm can perform well enough in a real‐time environment. Direct search algorithms are simple to implement and can be made more efficient by applying differential geometric techniques to the search methodology. The typical smoothness of the equations of motion for vehicular systems allows the objective function's stationarities to be handled in a straight‐forward way. Copyright © 2013 John Wiley & Sons, Ltd.
Childhood acute lymphoblastic leukemia in Nicaragua: Long‐term results in the context of an international cooperative program
Authors: Pacheco Carlos , Lucchini Giovanna , Valsecchi Maria Grazia , Malta Alberto , Conter Valentino , Flores Andronica , Biondi Andrea , Tognoni Gianni , Arguello Mercedes , Cavalli Franco , Silvestri Daniela , Lacayo Fulgencio Baez , Masera Giuseppe
Published: December 2013

Background

The aim of this paper is to describe the results of acute lymphoblastic leukemia (ALL) treatment in Nicaragua from 1995 to 2005 in the context of an international cooperation program.

Procedures

Patients <18 years with ALL were treated with two consecutive protocols (1995 and 2000). After a steroid prophase, a three‐drug induction was administered in protocol 1995, and a four‐drug induction, including asparaginase, was administered in protocol 2000. In protocol 2000, a modified BFM phase IB with cyclophosphamide, 6‐mercaptopurine and cytosine arabinoside was administered to patients at high risk (HR), who also received IV methotrexate (500 mg/m2) in the consolidation phase. Reinduction consisted of dexamethasone, vincristine, doxorubicin, cytosine arabinoside, and 6‐thioguanine administered over 7 (protocol 1995) or 4 (protocol 2000) weeks; reinduction was repeated twice for patients at HR. Maintenance consisted of p.o. 6‐mercaptopurine and methotrexate, and vincristine and dexamethasone pulses were added in the 2000 study. The total duration of therapy was 24 months.

Results

In total, 540 patients were treated. Overall, 7% of patients died during induction, and 9% abandoned treatment. At 5 and 10 years from diagnosis, event‐free survival (EFS) rates of 38.1% and 36.6%, respectively, and overall survival rates of 48.0% and 39.6%, respectively, were obtained, considering abandonment as an event.

Conclusions

In our experience, a 10‐year EFS of 36.6% was achieved in a country with limited resources. Factors limiting a higher success rate were treatment abandonment and a high relapse rate. Pediatr Blood Cancer 2014;61:827–832. © 2013 Wiley Periodicals, Inc.
Effect of interfacial properties on the thermophysical properties of 3D braided composites: 3D multiscale finite element study
Authors: Lu Zixing , Wang Chengyu , Xia Biao , Zhou Yuan
Published: December 2013

In this article, a new three‐dimensional (3D) finite element modeling is developed to investigate the effect of interfacial properties on the thermophysical properties of 3D braided composites. The yarn is considered as uniaxial fiber‐reinforced composites, and its effective thermophysical properties are obtained by a representative volume cell constructed using the collision algorithm. In addition, based on the periodic nonadiabatic temperature boundary conditions and displacement boundary conditions, the thermophysical properties of 3D braided composites are predicted and compared with the experimental results, in which a good agreement is achieved. A comparison is conducted between the effect of interfacial properties on the thermophysical properties of 3D four‐directional (4D) braided composites and that of 3D5D braided composites. The results acquired show that the interfacial properties are significant factors that affect the thermophysical properties of 3D4D braided composites, but they have no obvious effects on the thermophysical properties of 3D5D braided composites. POLYM. COMPOS., 35:1690–1700, 2014. © 2013 Society of Plastics Engineers
Mechanical and thermal properties of thermoplastic polyurethane‐toughened polylactide‐based nanocomposites
Authors: Liu Zheng‐Wei , Chou Hung‐Chia , Chen Szu‐Hsien , Tsao Ching‐Ting , Chuang Ching‐Nan , Cheng Li‐Chiun , Yang Chen‐Han , Wang Chih‐Kuang , Hsieh Kuo‐Huang
Published: December 2013

The crystallinity and mechanical and thermal properties of polylactide (PLA)‐based biodegradable‐engineered plastic nanocomposites were determined. The nanocomposites were composed of thermoplastic polyurethane (TPU)‐toughened PLA, Talcum (Talc) and organic modified clay (montmorillonite; OMC). The tensile and flexural tests showed that PLA blended with 10 wt% TPU, 4 wt% Talc powder and 2 wt% OMC had the highest modulus and strength without a loss of elongation. The heat distortion temperature (HDT) tests demonstrated that the thermally treated PLA‐based nanocomposites had an HDT of nearly double the HDT for untreated specimens. An analysis of the polymer using scanning electron microscopy demonstrated that the incorporation of inorganic fillers altered the heterogeneous morphology of the PLA/TPU blend. This study investigated the feasibility of using PLA‐based nanocomposites for practical use, including applications in the automotive and furniture industries. POLYM. COMPOS., 35:1744–1757, 2014. © 2013 Society of Plastics Engineers
Mechanical, thermal conductive, and dielectric properties of fluoroelastomer/reduced graphene oxide composites in situ prepared by solvent thermal reduction
Authors: Xing Yan , Bai Xin , Zhang Yong
Published: December 2013

Fluoroelastomer (FKM)/reduced graphene oxide (rGO) composites are in situ prepared by solvent thermal reduction method in N,N‐dimethylformamide (DMF) solution. The reduction of graphene oxide (GO) is characterized by X‐Ray photoelectron (XPS), ultraviolet–visible (UV–vis), and Fourier transform infrared (FTIR) spectra. GO and rGO are both efficient fillers to improve the mechanical properties of FKM. The dispersibility of rGO is improved after solvent thermal reduction which is confirmed by scanning electron micrograph (SEM) and X‐ray diffraction (XRD). The homogenous suspension of FKM/rGO composites in DMF can stay stable for more than a month. The dielectric permittivity of FKM/rGO (5 phr) is 26.4 at the frequency of 10−1 Hz, higher than the pure FKM (8.1). The thermal conductivity of rGO/FKM composites increases. POLYM. COMPOS., 35:1779–1785, 2014. © 2013 Society of Plastics Engineers
Coronal approach for measuring both fetal lateral ventricles: is there an advantage over the axial view?
Authors: Katorza Eldad , Duvdevani Nir , Jacobson Jeffrey‐Michael , Gilboa Yinon , Hoffmann Chen , Achiron Reuven
Published: December 2013

Objective

This study aimed to compare measurement of the lateral cerebral ventricular diameter using either the traditional axial view or the coronal plane.

Materials and methods

We performed a prospective study on 144 fetuses, 77 evaluated as part of a routine fetal scan and 67 referred for a neurosonogram. Distal lateral ventricles were measured both in axial and coronal plane.

Results

Good visualization of the ventricles was achieved in 91% of the cases using the coronal plane (both ventricles) and in 95% of the cases using the axial plane (only the distal ventricle) (p > 0.001). The mean width of the distal lateral ventricle in the axial plane was 7.9 ± 1.9 mm versus 8.2 ± 1.9 mm on the coronal plane (p < 0.001). This larger diameter by 0.3 mm was not dependent on the indication for the scan or the gestational age. Slight asymmetry was present on coronal images in the routine group (0.2 mm), and that was even larger in the referral group (1.6 mm) (p < 0.001).

Conclusion

Coronal measurement of both ventricles is feasible and has the advantage over measurement in the axial view in which only the distal ventricle is clearly visible and measurable. © 2013 John Wiley & Sons, Ltd.
Dual length morphological model for bulk‐heterojunction, polymer‐based solar cells
Authors: Shen Hao , Zhang Wenluan , Mackay Michael E.
Published: December 2013

We present a dual length morphological model for the active layer of bulk‐heterojunction, polymer‐based solar cells using results from neutron and X‐ray scattering techniques. Two critical characteristic lengths are found in the mixtures composed of poly(3‐hexylthiophene) (P3HT) and [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM). A characteristic length at 15 nm is the local characteristic of the P3HT crystals and PCBM agglomerations, which is independent of the bulk composition upon relaxation by thermal annealing. Conversely, a larger bicontinuous structure described by Teubner–Strey model with phase distances between 23 and 35 nm forms only after thermal annealing, which is highly correlated to the bulk compositions. These results suggest phase separation between the polymer and fullerene can only be partially manipulated by simple processing techniques such as coating conditions and annealing, and a more rigorous design of the morphology should be implemented in the future. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2014, 52, 387–396
Pd@SnO2 and SnO2@Pd Core@Shell Nanocomposite Sensors
Authors: Gyger Fabian , Sackmann André , Hübner Michael , Bockstaller Pascal , Gerthsen Dagmar , Lichtenberg Henning , Grunwaldt Jan‐Dierk , Barsan Nicolae , Weimar Udo , Feldmann Claus
Published: December 2013

Pd@SnO2 and SnO2@Pd core@shell nanocomposites are prepared via a microemulsion approach. Both nanocomposites exhibit high‐surface, porous matrices of SnO2 shells (>150 m2 g−1) with very small SnO2 crystallites (<10 nm) and palladium (Pd) nanoparticles (<10 nm) that are uniformly distributed in the porous SnO2 matrix. Although similar by first sight, Pd@SnO2 and SnO2@Pd are significantly different in view of their structure with Pd inside or outside the SnO2 shell and in view of their sensor performance. As SMOX‐based sensors (SMOX: semiconducting metal oxide), both nanocomposites show a very good sensor performance for the detection of CO and H2. Especially, the Pd@SnO2 core@shell nanocomposite is unique and shows a fast response time (τ90 < 30 s) and a very good response at low temperature (<250 °C), especially under humid‐air conditions. Extraordinarily high sensor signals are observed when exposing the Pd@SnO2 nanocomposite to CO in humid air. Under these conditions, even commercial sensors (Figaro TGS 2442, Applied Sensor MLC, E2V MICS 5521) are outperformed.
Versatile Graphene Quantum Dots with Tunable Nitrogen Doping
Authors: Dai Yunqian , Long Huan , Wang Xiaotian , Wang Yueming , Gu Qing , Jiang Wei , Wang Youcheng , Li Cancan , Zeng Tingying Helen , Sun Yueming , Zeng Jie
Published: December 2013

This paper reports a facile fabrication of N‐doped graphene quantum dots (N‐GQDs) showing controllable chemical properties through a hydrothermal treatment. The N‐GQDs have a uniform size of 3.06 ± 0.78 nm and prefer the equilibrium shapes of circle and ellipse due to the minimization of edge free energy. The N/C atomic ratio in N‐GQDs can be precisely tailored in a range from 8.3 at% to 15.8 at% by simply controlling the concentration of N source (ammonium hydroxide). One order of magnitude quantum yield of 34.5% is achieved by N‐GQDs, compared with the N‐free GQDs, as the substitutional N has an essential role in more effective radiative emission. Excessive N dopants in N‐GQDs can lead to photoluminescence quenching, through nonradiative transition back to the ground state. The N‐GQDs are further found to be suitable as photocurrent conversion materials due to benign energy matching with anatase nanofibers, the ultrafast electron injection at their interface, and efficient electron transfer. This work provides an efficient and inspiring approach to engineering both chemical components and physical properties of N‐GQDs, and will therefore promote their basic research and applications in energy conversion.
Study of incorporation efficiency of different precursor salts in fabrication of rare‐earth doped optical fibers
Authors: Dhar Anirban , Das Shyamal , Paul Mukul Chandra , Pal Atasi , Sen Ranjan
Published: December 2013

A comparative study on the influence of different precursor salts of Er and Al for fabrication of rare‐earth‐doped optical fibers by modified chemical vapor deposition‐solution doping is presented. Experimental results reveal that among the different precursor salts under investigation halide precursors exhibit the highest incorporation efficiency. A plausible explanation of the observed result is proposed. The results of a model conductivity experiment support our proposition.
Electrical characteristics of lead iodide crystal devices on flexible substrate under mechanical tensile strain
Authors: Sun Hui , Zhu Xinghua , Yang Dingyu , Yang Jun , Gao Xiuying , Li Xu
Published: December 2013

We report the experimental study on the electrical characteristics of a flexible device based on PbI2 crystal. It is found that the ohmic contact characteristics remain the same, but the dark current decreased with increasing mechanical tensile strain. The value of the bandgap Eg = 2.28 eV obtained from optical absorption spectra is kept in a steady state during bending, but a widening of the band‐tail state occurs.
Luminescence centers and spectrum characteristics of a novel Eu2+‐activated hexa‐aluminate CaZrBAl9O18
Authors: Yu Ruijin , Li Hongjuan , Ma Hailong , Wang Caifeng , Wang Huan
Published: December 2013

A new blue‐emitting phosphor of Eu2+‐activated hexa‐aluminate CaZrBAl9O18 was synthesized by a conventional solid‐state reaction method. The crystalline phase formation was confirmed by X‐ray powder diffraction (XRD) measurements. The photoluminescence excitation and emission spectra, the luminescence decay curves and the time‐resolved spectra of CaZrBAl9O18:Eu2+ were taken to investigate the luminescence characteristics. The dependence of CaZrBAl9O18:Eu2+ luminescence intensity on the Eu2+ doping concentrations was investigated. This phosphor can be efficiently excited by UV light and presents blue luminescence. There is one kind of Eu2+ luminescence center in the lattices, which was confirmed by the time‐resolved luminescence spectra. The temperature‐dependent luminescence intensity was measured and the activation energy (ΔE) for thermal quenching was reported. The phosphor shows high luminescence intensity and an excellent thermal stability on temperature quenching.

Eu2+‐doped hexa‐aluminate CaZrBAl9O18 presents bright blue‐emitting luminescence with high thermal quenching; only one Eu2+ center was confirmed in this hexa‐aluminate lattices.
Electronic structure and band gap of oxygen bearing c‐Zr3N4 and of c‐Hf3N4 by soft X‐ray spectroscopy
Authors: Yablonskikh Mikhail , Dzivenko Dmytro , Bourguille Judith , Riedel Ralf , Magnano Elena , Parmigiani Fulvio , Zerr Andreas
Published: December 2013

Electronic band structures of two novel semiconducting nitrides of the group‐IV elements of Th3P4‐type crystal structure, c‐M3N4, where MZr or Hf, is investigated using an element specific soft X‐ray spectroscopy for the first time. From the pairs of N 1s X‐ray absorption and N 2p → 1s resonant X‐ray emission spectra partial densities of states (PDOS) of nitrogen, predicted to be strongly hybridized with those of the metals, are obtained for both compounds. From these data the electronic band gaps of oxygen bearing c‐Zr3N4 and of c‐Hf3N4, predicted before to be direct or nearly direct, are derived to be Eg = 1.6 eV and Eg = 1.8 eV, respectively. While the experimentally determined Eg for c‐Hf3N4 agrees with the theoretical one obtained using the local density approximation (LDA) method, the Eg measured for oxygen bearing c‐Zr3N4 is significantly higher than those calculated using both the LDA and the generalized gradient approximation method. The examined compounds, having high hardness, elastic moduli and oxidation resistance, appear to be multifunctional materials suitable also for applications as (opto)electronic materials.

Band gap evolution in c‐M3N4 nitrides as a function of the cation type, Zr or Hf.
Perspectives on point defect thermodynamics
Authors: Rogal Jutta , Divinski Sergiy V. , Finnis Mike W. , Glensk Albert , Neugebauer Jörg , Perepezko John H. , Schuwalow Sergej , Sluiter Marcel H. F. , Sundman Bo
Published: December 2013

We review and discuss methods for including the role of point defects in calculations of the free energy, composition and phase stability of elements and compounds. Our principle aim is to explain and to reconcile, with examples, the perspectives on this problem that are often strikingly different between exponents of CALPHAD, and others working in the overlapping fields of physics, chemistry and materials science. Current methodologies described here include the compound energy formalism of CALPHAD, besides the rather different but related canonical and grand‐canonical formalisms. We show how the calculation of appropriate defect formation energies should be formulated, how they are included in the different formalisms and in turn how these yield equilibrium defect concentrations and their contribution to free energies and chemical potentials. Furthermore, we briefly review the current state‐of‐the‐art and challenges in determining point defect properties from first‐principles calculations as well as from experimental measurements.
Ginsenoside Rg3 Up‐regulates the Expression of Vascular Endothelial Growth Factor in Human Dermal Papilla Cells and Mouse Hair Follicles
Authors: Shin Dae Hyun , Cha Youn Jeong , Yang Kyeong Eun , Jang Ik‐Soon , Son Chang‐Gue , Kim Bo Hyeon , Kim Jung Min
Published: December 2013

Crude Panax ginseng has been documented to possess hair growth activity and is widely used to treat alopecia, but the effects of ginsenoside Rg3 on hair growth have not to our knowledge been determined. The aim of the current study was to identify the molecules through which Rg3 stimulates hair growth. The thymidine incorporation for measuring cell proliferation was determined. We used DNA microarray analysis to measure gene expression levels in dermal papilla (DP) cells upon treatment with Rg3. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF) in human DP cells were measured by real‐time polymerase chain reaction and immunohistochemistry, respectively. We also used immunohistochemistry assays to detect in vivo changes in VEGF and 3‐stemness marker expressions in mouse hair follicles. Reverse transcription polymerase chain reaction showed dose‐dependent increases in VEGF mRNA levels on treatment with Rg3. Immunohistochemical analysis showed that expression of VEGF was significantly up‐regulated by Rg3 in a dose‐dependent manner in human DP cells and in mouse hair follicles. In addition, the CD8 and CD34 were also up‐regulated by Rg3 in the mouse hair follicles. It may be concluded that Rg3 might increase hair growth through stimulation of hair follicle stem cells and it has the potential to be used in hair growth products. Copyright © 2013 John Wiley & Sons, Ltd.
Daily Inhalation of α‐Pinene in Mice: Effects on Behavior and Organ Accumulation
Authors: Satou Tadaaki , Kasuya Hikaru , Maeda Kazumi , Koike Kazuo
Published: December 2013

In phytotherapy, essential oils tend to be used daily for a period of days or weeks, rather than in a single application. However, the literature contains very little information on repeated use of essential oils. In this study, we investigated the effects on behavior and the accumulation in the brain and liver of α‐pinene, an essential oil component, when inhaled by mice. Animals were individually housed in cages for 1 week. Mice inhaled α‐pinene or water vapor (negative control) for 90 min/day for 1 day, 3 days, or 5 days, and they were then submitted to the elevated plus maze test for 10 min. We used gas chromatography with flame ionization detection to quantify concentrations of α‐pinene in the brain and liver. There was significant anxiolytic‐like activity, which remained constant for the 5 days' inhalation of α‐pinene. On the other hand, the accumulation of α‐pinene in the brain and liver peaked on the third day of inhalation. The existence of stress related to the new environment appears to have affected the change in the accumulation of α‐pinene in the internal organs, keeping the anxiolytic‐like action constant. Copyright © 2013 John Wiley & Sons, Ltd.
The roles of diurnal forcing and large‐scale moisture transport for initiating rain over northwest Australia in a GCM
Authors: Ackerley D , Berry G. , Jakob C. , Reeder M. J.
Published: December 2013

The representation of rainfall, and in particular its diurnal cycle, is generally poor in general circulation models (GCMs). Nonetheless, studies make use of GCMs in future climate projections in regions where precipitation has a strong diurnal cycle. In this study we evaluate whether one GCM (ACCESS1.3) can represent the rainfall in such a region (Australia) where the diurnal cycle of rainfall is produced as a result of both the destabilisation of the boundary layer (convection) and a larger‐scale reorganisation of the low‐level flow, the latter of which may be resolved by a GCM. In northern and eastern Australia, where the diurnal cycle of rainfall is controlled by convective processes, the GCM produces rain 3 to 6 h too early in the day. Nevertheless, the model represents the continental‐scale reorganisation of the low‐level circulation that results from the diurnal cycle of surface heating and cooling. A nocturnal low‐level jet forms over the western half of the continent with strong convergence at the jet exit, which initiates rain overnight in the continental northwest, in agreement with previous work. The model also captures the change in the air‐flow direction, from a southeasterly to a northeasterly, responsible for bringing the necessary moisture for precipitation to occur. Thus, while the model may have a tendency to initiate convection too early, it is able to represent the larger‐scale nocturnal reorganisation of the flow and the associated rainfall.
Robust Control Charts for Monitoring Process Variability in Phase I Multivariate Individual Observations
Authors: Variyath Asokan Mulayath , Vattathoor Jayasankar
Published: December 2013

Multivariate control charts are widely used in various industries to monitor the shifts in process mean and process variability. In Phase I monitoring, control limits are computed using the historical data, and control charts based on classical estimators (sample mean and the sample covariance) are highly sensitive to the outliers in the data. We propose robust control charts with high breakdown robust estimators based on the re‐weighted minimum covariance determinant and the re‐weighted minimum volume ellipsoid to monitor the process variability of multivariate individual observations in Phase I data under multivariate exponentially weighted mean square error and multivariate exponentially weighted moving variance schemes. The control limits are computed empirically, and the performance of the proposed charts is assessed with Monte Carlo simulations by considering different data scenarios. The proposed robust control charts are shown to perform better than charts based on classical estimators. Copyright © 2013 John Wiley & Sons, Ltd.
Using Fuzzy Cost‐Based FMEA, GRA and Profitability Theory for Minimizing Failures at a Healthcare Diagnosis Service
Authors: Abbasgholizadeh Rahimi Samira , Jamshidi Afshin , Ait‐Kadi Daoud , Ruiz Angel
Published: December 2013

This paper proposes an integrated approach to identify, evaluate and improve the potential failures in a service setting. This integrated approach combines Fuzzy cost‐based service‐specific FMEA (FCS‐FMEA), Grey Relational Analysis (GRA) and profitability theory for better prioritization of the service failures by considering cost as an important issue and using the profitability theory in a way that the corrective actions costs are taken into account. Considering profitability with FCS‐FMEA and GRA reduces the losses caused by failure occurrence. Besides, a maximization linear mathematical problem is used to select the best mix of failures to be repaired. We apply our approach to an academic example concerning the potential failures diagnosis of the Internal Medicine service of a hospital located in Seoul, Korea. We applied our approach and solved the associated maximization problem by a commercial solver, producing an optimal solution which indicates the most convenient mix of failures to be repaired by considering available budget. Copyright © 2013 John Wiley & Sons, Ltd.
Metabolite identification studies on amiodarone in in vitro (rat liver microsomes, rat and human liver S9 fractions) and in vivo (rat feces, urine, plasma) matrices by using liquid chromatography with high‐resolution mass spectrometry and multiple‐stage mass spectrometry: Characterization of the diquinone metabolite supposedly responsible for the drug's hepatotoxicity
Authors: Varkhede Ninad Ramesh , Jhajra Shalu , Ahire Deepak Suresh , Singh Saranjit
Published: December 2013

RATIONALE

Several mechanisms have been anticipated for the toxicity of amiodarone, such as oxidative stress, lipid peroxidation, phospholipidosis, free radical generation, etc. Amiodarone is structurally similar to benzbromarone, an uricosuric agent, which was withdrawn from European markets due to its idiosyncratic hepatotoxicity. A proposed reason behind the toxicity of benzbromarone was the production of a reactive ortho‐diquinone metabolite, which was found to form adducts with glutathione. Therefore, taking a clue that a similar diquinone metabolite of amiodarone may be the reason for its hepatotoxicity, metabolite identification studies were carried out on the drug using liquid chromatography/mass spectrometry (LC/MS) tools.

METHODS

The studies involved in vitro (rat liver microsomes, rat liver S9 fraction, human liver S9 fraction) and in vivo (rat feces, urine, plasma) models, wherein the samples were analyzed by employing LC/HRMS, LC/MSn and HDE‐MS.

RESULTS AND CONCLUSIONS

A total of 26 metabolites of amiodarone were detected in the investigated in vitro and in vivo matrices. The suspected ortho‐diquinone metabolite was one of them. The formation of the same might be an added reason for the hepatotoxicity shown by the drug. Copyright © 2013 John Wiley & Sons, Ltd.
Lake Louise Water (USGS47): A new isotopic reference water for stable hydrogen and oxygen isotope measurements
Authors: Qi Haiping , Lorenz Jennifer M. , Coplen Tyler B. , Tarbox Lauren , Mayer Bernhard , Taylor Steve
Published: December 2013

RATIONALE

Because of the paucity of isotopic reference waters for daily use, a new secondary isotopic reference material has been prepared from Lake Louise water from Alberta, Canada, for international distribution.

METHODS

This water was filtered, homogenized, loaded into glass ampoules, sealed with a torch, autoclaved to eliminate biological activity, and measured by dual‐inlet isotope‐ratio mass spectrometry. This isotopic reference water is available by the case of 144 glass ampoules containing 5 mL of water in each ampoule.

RESULTS

The δ2H and δ18O values of this reference water are −150.2 ± 0.5 ‰ and −19.80 ± 0.02 ‰, respectively, relative to VSMOW, on scales normalized such that the δ2H and δ18O values of SLAP reference water are, respectively, –428 and −55.5 ‰. Each uncertainty is an estimated expanded uncertainty (U = 2uc) about the reference value that provides an interval that has about a 95 % probability of encompassing the true value.

CONCLUSIONS

This isotopic reference material, designated as USGS47, is intended as one of two isotopic reference waters for daily normalization of stable hydrogen and stable oxygen isotopic analysis of water with a mass spectrometer or a laser absorption spectrometer. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.
Identification of unusual butanetriol dialkyl glycerol tetraether and pentanetriol dialkyl glycerol tetraether lipids in marine sediments
Authors: Zhu Chun , Meador Travis B. , Dummann Wolf , Hinrichs Kai‐Uwe
Published: December 2013

RATIONALE

Glycerol serves as the principal backbone moiety bound to various acyl/alkyl chains for membrane lipids of Eukarya, Bacteria, and Archaea. In this study, we report a suite of unusual tetraether lipids in which one of the two conventional glycerol backbones is substituted by butanetriol or pentanetriol.

METHODS

Identification of these lipids was achieved via diagnostic fragments and their expected acetylation products using liquid chromatography/mass spectrometry (LC/MS), and their diagnostic ether cleavage products using gas chromatography/mass spectrometry (GC/MS).

RESULTS

We observed structural variations in the polyol backbones and alkyl chains and term these core lipid derivatives: isoprenoidal butanetriol dialkyl glycerol tetraethers (iso‐BDGTs), isoprenoidal pentanetriol dialkyl glycerol tetraethers (iso‐PDGTs), and hybrid isoprenoidal/branched BDGTs and PDGTs (ib‐BDGTs, ib‐PDGTs). Of these, iso‐BDGTs were the most abundant with a methylation at either the sn‐1 or sn‐3 position of glycerol and were also found as part of intact polar lipids, adjoined to mono‐ or diglycosidic headgroups. Iso‐BDGTs and iso‐PDGTs are likely produced by Archaea, as indicated by the presence of the characteristic biphytanyl moieties.

CONCLUSIONS

Butanetriol‐ and pentanetriol‐based tetraether lipids occur in modern estuarine and deeply buried subseafloor sediments, suggesting the presence of alternative backbones in archaeal lipids. Copyright © 2013 John Wiley & Sons, Ltd.
A mixed cluster ion beam to enhance the ionization efficiency in molecular secondary ion mass spectrometry
Authors: Wucher Andreas , Tian Hua , Winograd Nicholas
Published: December 2013

RATIONALE

Chemical modification of a rare gas cluster ion beam (GCIB) to increase the intensity of desorbed molecular ions in secondary ion mass spectrometry experiments relative to the pure Ar cluster.

METHODS

Doping of the GCIB by mixing small concentration levels (1–3% relative partial pressure) of CH4 into the Ar gas driving the cluster ion source.

RESULTS

Mass spectra measured on a trehalose film using the doped GCIB exhibit enhanced molecular ion signals. From depth profiling experiments, the results are shown to arise from an increase in the ionization efficiency of the sputtered molecules rather than a change in the sputtering yield of neutral species.

CONCLUSIONS

Tuning of the chemistry of mixed clusters is suggested as a general approach to enhancing the ionization probability of sputtered molecules. Copyright © 2013 John Wiley & Sons, Ltd.
Stability and stabilization of piecewise‐affine slab systems subject to Wiener process noise
Authors: Raouf Jamila , Rodrigues Luis
Published: December 2013

The main contribution of this paper is to propose a convex formulation of sufficient conditions for both stability analysis and synthesis of stabilizing controllers for stochastic piecewise affine (PWA) systems with multiplicative noise. One of the main difficulties in PWA systems is the fact that the affine terms in the dynamics make it extremely difficult to formulate the synthesis problem as a convex optimization or even convex feasibility program. The presence of multiplicative noise modeled as a Wiener process adds an additional level of difficulty to the analysis and synthesis procedures. Sufficient conditions for stability of stochastic PWA slab systems in the mean square sense are developed first using a stochastic globally quadratic Lyapunov function. Second, PWA state feedback controllers are designed such that the closed‐loop system is stochastically exponentially mean square stable. The conditions for both stability and stabilization are formulated as LMIs, which can then be solved efficiently using currently available software packages. A numerical example shows the effectiveness of the approach. Copyright © 2013 John Wiley & Sons, Ltd.
Automatic Driving on Ill‐defined Roads: An Adaptive, Shape‐constrained, Color‐based Method
Authors: Ososinski Marek , Labrosse Frédéric
Published: December 2013

Autonomous following of ill‐defined roads is an important part of visual navigation systems. This paper presents an adaptive method that uses a statistical model of the color of the road surface within a trapezoidal shape that approximately corresponds to the projection of the road on the image plane. The method does not perform an explicit segmentation of the images but instead expands the shape sideways until the match between shape and road worsens, simultaneously computing the color statistics. Results show that the method is capable of reactively following roads, at driving speeds typical of the robots used, in a variety of situations while coping with variable conditions of the road such as surface type, puddles, and shadows. We extensively evaluate the proposed method using a large number of datasets with ground truth (available from http://www.aber.ac.uk/en/cs/research/ir/dss/). We moreover evaluate many color spaces in the context of road following, and we find that the color spaces that separate luminance from color information perform best, especially if the luminance information is discarded.
The study of paramagnetic self‐assembled monolayers formed by nitroxide radical (TEMPO)3O3P on HOPG
Authors: Naruszewicz Michal , Busiakiewicz Adam , Grabowski Grzegorz , Olejniczak Wielislaw
Published: December 2013

The studies of (TEMPO)3O3P molecules (tri‐(2,2,6,6‐tetramethyl‐1‐oxyl‐4‐piperidyl) phosphite) and their monolayers formed on highly oriented pyrolytic graphite (HOPG) are presented. (TEMPO)3O3P is synthesized from TEMPOL precursor (4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐1‐oxyl). We focused on electron paramagnetic resonance (EPR) and scanning tunnelling microscopy (STM) investigations. The EPR experiments demonstrate the paramagnetism of (TEMPO)3O3P in powdered form and in solution. Furthermore, these paramagnetic properties of (TEMPO)3O3P are preserved after the deposition on HOPG substrate. The STM studies show that (TEMPO)3O3P molecules have a strong tendency to form self‐assembled monolayers (SAMs). The detailed STM images let us to explore the structure of (TEMPO)3O3P on HOPG and propose a structural model for the observed SAMs. Copyright © 2013 John Wiley & Sons, Ltd.
The social underpinnings of absorptive capacity: The moderating effects of structural holes on innovation generation based on external knowledge
Authors: Tortoriello Marco
Published: December 2013

Building on absorptive capacity and social network research, in this paper I investigate how individuals inside the organization use external knowledge to generate innovations. Through original sociometric data collected from 276 scientists, researchers, and engineers from the Research and Development division of a large multinational high‐tech company, I show that the effects of external knowledge on individuals' innovativeness are contingent upon individuals' position in the internal social structure. In particular, results indicate that the positive effects of external knowledge on innovation generation become more positive when individuals sourcing external knowledge span structural holes in the internal knowledge‐sharing network. Copyright © 2013 John Wiley & Sons, Ltd.
Dynamic Recrystallization (DRX) Analysis of Heavy Reduction Process with Extra‐Thickness Slabs
Authors: Zhao Xinkai , Zhang Jiongming , Lei Shaowu , Wang Yuanning
Published: December 2013

Limited by reduction radio, heavy plates manufactured from slabs are always subjected to deterioration of soundness and mechanical properties. For overcoming these defects, in the current works, a new approach, named Heavy Reduction Process to Improve Segregation and Porosity (HRPISP), was presented. The aim this study was to investigate the process of rear heavy reduction, felling only one segment, at the end of slab solidification (about 0.85 solid fraction in the centerline). According to the real production condition of superheat, casting speed and spray intensity, a two‐step strategy was preceded using software THERCAST3D firstly. Then, a special forging simulation product FORGE3D had been used, based on the end results of THERCAST3D, to simulate the rear heavy reduction process. Results showed the distribution of temperature, strain and strain rate under both types of segment. Interestingly, something valuable had been found. After the analysis of dynamic recrystallization (DRX) model, derived from the slabs hot uniaxial compressive tests, it revealed that a certain degree of XDRX was existed. In addition, there were significant differences in distribution of XDRX volume fraction and grain size. The results of such studies provided some valuable information on the parameters of heavy reduction and the design of reduction segment.
Numerical and Physical Modeling of Liquid Steel Active Flow in Tundish with Subflux Turbulence Controller and Dam
Authors: Cwudziński Adam
Published: December 2013

This paper presents the results of a computer simulation and laboratory experiments carried out to describe the hydrodynamics of steel active flow in the tundish. One of the parameters describing the correct influence of FCDs on the tundish operation is the description of the active flow zone (dispersed plug flow and well mixed volume flow). The facility under investigation is a single‐nozzle tundish designed for casting concast slabs. Computer simulations of liquid steel flow were performed using the commercial program Ansys‐Fluent. For the validation of the numerical model and verification of the hydrodynamic conditions occurring in the examined tundish furniture variants, obtained from the computer simulations, a physical model of the tundish was employed. During laboratory tests simulating the process of steel flowing through the tundish, E type RTD curves were recorded, which were then juxtaposed with results obtained from computer simulations. In order to obtain a complete hydrodynamic picture in the tundish furniture variants tested, the computer simulations were performed for both isothermal and non‐isothermal conditions.
Fundamental Investigations on the Corrosion of ZrO2–CRefractories during Interaction with a Casting Mould Meniscus Slag
Authors: Kumar Anup , Khanna Rita , Spink John , Sahajwalla Veena
Published: December 2013

The degradation behavior of Zirconia – 20% carbon refractory was investigated during high temperature (1550 °C) contact with a casting mould meniscus slag containing 50% MnO, 25% SiO2, and 25% Al2O3. Using the sessile drop approach, the transient progress of corrosion reactions was investigated as a function of time; in‐depth characterization and analysis of reacted assemblies was carried out using optical and scanning electron microscopy. Optical micrographs showed a significant penetration of slag within the refractory substrate, with very little slag remaining behind after 15 min of contact. In situ carbothermic reduction of zirconia and the presence of reducible oxides in the slag significantly depleted carbon from the substrate further aiding the penetration of slag. Interaction between slag and zirconia resulted in the depletion of phase‐stabilizing Y2O3from zirconia granules resulting in their fragmentation and subsequent diffusion in slag rich regions. An aggressive all‐round corrosion was observed with extensive refractory degradation over a period of time; a number of reaction products such as Mn5Si3were also observed. These experimental investigations were supplemented with thermodynamic investigations using FactSage.
Desulfurization of Hot Metal Through In Situ Generation of Magnesium in 30‐kg Molten Iron Bath‐Influence of Inert Gas Flow Rate
Authors: Kumar Anil , Chacko Zachariah Elanjickal , Malathi Madurai , Godiwalla Kesri Mino , Ajmani Satish Kumar , Ranganathan Srinivasan
Published: December 2013

In situ generation of magnesium has been used for desulfurizing 30‐kg liquid iron bath. The experiments were carried out under conditions close to industrial operation. This is the first experimental investigation of this scale ever to be reported. The influence of the flow rate of inert gas on the generation of magnesium and the desulfurization process was studied. The degree of desulfurization was modeled in terms of efficiency of generation of magnesium in a reactor designed for this purpose and the efficiency of utilization of magnesium in the bath for desulfurization. The generation of magnesium in the reactor is controlled by mass transfer kinetics in the porous tablets of (MgO + Al) mixture. It is not influenced by the flow rate of inert gas through the reactor. The degree of utilization of magnesium in the liquid iron bath, for desulfurization, is significantly influenced by the flow rate of inert gas. The predictions of the model are consistent with experimental observations. The efficiency of utilization of magnesium for desulfurization in the bath is comparable to that of the current industrial practice where a mixture of CaO and Mg is used for desulfurization.
Internationalization in Marketing—From Theory to Practice by Means of a Delphi Study
Authors: Czinkota Michael R. , Pinkwart Andreas
Published: December 2013

International marketing matters to firms and consumers when going abroad. Given the general limitation of resources, it is important to set priorities as to one's international marketing engagement. The articles presented in this special edition reflect the research presented at the annual conference of the Global Marketing Special Interest Group of the American Marketing Association, which took place in 2012 in Cancun, Mexico. The participants focused on ideas and alternatives for the exploration of developing knowledge in international marketing from both an academic and a practitioner perspective. In addition to the leading presentations offered in this volume, there was also a key effort made to develop, with the use of a Delphi research study, which is presented in this article, insights into the future role of international marketing and its cross‐disciplinary and cross‐national opportunities. © 2013 Wiley Periodicals, Inc.
Questioning Western Knowledge Transfer Methodologies: Toward a Reciprocal and Intercultural Transfer of Knowledge
Authors: Bengoa Dolores Sanchez , Kaufmann Hans Ruediger
Published: December 2013

The rapid development of western European knowledge‐based societies has a drastic effect on the development of eastern European societies. Special attention should be paid to the past three years of economic crisis, where a shift of existing economic paradigms has occurred. In order to navigate through these turbulent times, many companies, as an option to survive or expand, have formed cross‐border alliances and cooperations. Due to these cross‐border initiatives, the geographic movement of employees and, implicitly, the flow of intellectual capital, play an important role. Paradoxically, however, the process of knowledge transfer has been affected by several shortcomings, for example, the knowledge receiver's lack of absorptive capacity or cognitive learning, a knowledge applicability gap, or the rise of knowledge sharing barriers.

The reason for this situation lies in the flawed knowledge transfer process. This approach is characterized by a unidirectional flow of knowledge from the West, reflecting an ethnocentric approach; inappropriate attitudes on behalf of the knowledge transmitter and the knowledge receiver; by knowledge not being culturally embedded, which leads to an alienation of knowledge; and, finally, to a lack of cultural awareness and preparedness on behalf of the westerners.

This article applies a phenomenological approach. By using grounded theory, it contributes to a better understanding of the complexity of the problems and its implications on management from a multidisciplinary perspective. It provides solutions to improve the knowledge transfer process between eastern and western European cooperations based on an intercultural and reciprocal methodology and a new conducive learning environment. © 2013 Wiley Periodicals, Inc.