bluuebunny/crossref_metadata_2025 huggingface dataset:
Price‐cap Regulation, Uncertainty and the Price Evolution of New Pharmaceuticals
Authors: Shajarizadeh Ali , Hollis Aidan
Published: July 2014

This paper examines the effect of the regulations restricting price increases on the evolution of pharmaceutical prices. A novel theoretical model shows that this policy leads firms to price new drugs with uncertain demand above the expected value initially. Price decreases after drug launch are more likely, the higher the uncertainty. We empirically test the model's predictions using data from the Canadian pharmaceutical market. The level of uncertainty is shown to play a crucial role in drug pricing strategies. © 2014 The Authors. Health Economics Published by John Wiley & Sons Ltd.
How Do Hospitals Respond to Market Entry? Evidence from a Deregulated Market for Cardiac Revascularization
Authors: Li Suhui , Dor Avi
Published: July 2014

Regulatory entry barriers to hospital service markets, namely Certificate of Need (CON) regulations, are enforced in many US states. Policy makers in other states are considering reinstating CON policies in tandem with service expansions mandated under the Affordable Care Act. Although previous studies examined the volume effects of CON, demand responses to actual entry into local hospital markets are not well understood. In this paper, we empirically examine the demand‐augmenting, demand‐redistribution, and risk‐allocation effects of hospital entry by studying the cardiac revascularization markets in Pennsylvania, a state in which dynamic market entry occurred after repeal of CON in 1996. Results from interrupted time‐series analyses indicate demand‐augmenting effects for coronary artery bypass graft (CABG) and business‐stealing effects for percutaneous coronary intervention (PCI) procedures: high entrant market share mitigated the declining incidence of CABG, but it had no significant effect on the rising trend in PCI use, among patients with coronary artery disease. We further find evidence that entry by new cardiac surgery centers tended to sort high‐severity patients into the more invasive CABG procedure and low‐severity patients into the less invasive PCI procedures. These findings underscore the importance of considering market‐level strategic responses by hospitals when regulatory barriers are rescinded. Copyright © 2014 John Wiley & Sons, Ltd.
Rare case study of a primary carcinoma of the petrous bone and a brief literature review
Authors: Atallah Ihab , Karkas Alexandre , Righini Christian Adrien , Lantuejoul Sylvie , Schmerber Sébastien
Published: July 2014

Background

Temporal bone carcinoma is an aggressive tumor with multiple unconfirmed risk factors.

Methods and Results

Herein, we present a rare case of a primary petrous bone carcinoma in a female patient (65 years old) with an irrelevant medical history. She presented a postauricular swelling that revealed a multilocular osteolytic cystic lesion of the mastoid portion of the temporal bone on the CT scan. The patient underwent resection of the lesion and pathological analysis revealed moderately to well‐differentiated squamous cell carcinoma. Postoperative radiotherapy was carried out. Until the present time, the patient shows complete remission on regular clinical and radiological follow‐up.

Conclusion

Although no widely accepted strategy for managing temporal bone tumors exists, a review of the literature showed that surgery with or without radiotherapy is the treatment of choice. Preoperative assessment and accurate staging are vital in ensuring that the treatment is adequate for each disease stage. © 2014 Wiley Periodicals, Inc. Head Neck 37: E45–E48, 2015
Cost‐effectiveness of positron emission tomography‐CT in the evaluation of cancer of unknown primary of the head and neck
Authors: Smith Kristine A. , Dort Joseph C. , Hall Stephen F. , Rudmik Luke
Published: July 2014

Background

Positron emission tomography (PET)‐CT is a useful diagnostic adjunct for cancer unknown primary (CUP) of the head and neck; however, the increased cost has not been justified with an economic evaluation in this patient population.

Methods

A decision tree analysis was performed from the perspective of the third party payer. Primary outcome was cost per life year gained ($/LYG). The 2 comparative groups were: (1) PET‐CT followed by panendoscopy versus (2) panendoscopy alone.

Results

The incremental cost‐effectiveness ratios for N1, N2, and N3 CUP were $369.83/LYG, $329.43/LYG, and $4900.28/LYG, respectively. The sensitivity analysis demonstrated a 96.8%, 97.1%, and 60.1% certainty that PET‐CT is cost‐effective for CUP with N1, N2, and N3 disease, respectively.

Conclusion

The use of PET‐CT in patients with N1 and N2 CUP is the cost‐effective choice. The cost‐effectiveness in N3 CUP is questionable and should be used on an individual case basis. © 2014 Wiley Periodicals, Inc. Head Neck 37: 1781–1787, 2015
Towards medicines regulatory authorities' quality performance improvement: value for public health
Authors: Pejović Gordana , Filipović Jovan , Tasić Ljiljana , Marinković Valentina
Published: July 2014

The purpose of this article is to explore the possibility of implementing total quality management (TQM) principles in national medicines regulatory authorities in Europe to achieve all public health objectives. Bearing in mind that medicines regulation is a governmental function that serves societal objectives to protect and promote public health, measuring the effective achievement of quality objectives related to public health is of utmost importance. A generic TQM model for meeting public health objectives was developed and was tested on 10 European national medicines regulatory authorities with different regulatory performances. Participating national medicines regulatory authorities recognised all TQM factors of the proposed model in implemented systems with different degrees of understanding. An analysis of responses was performed within the framework of two established criteria—the regulatory authority's category and size. The value of the paper is twofold. First, the new generic TQM model proposes to integrate four public health objectives with six TQM factors. Second, national medicines regulatory authorities were analysed as public organisations and health authorities to develop a proper tool for assessing their regulatory performance. The paper emphasises the importance of designing an adequate approach to performance measurement of quality management systems in medicines regulatory authorities that will support their public service missions. Copyright © 2014 John Wiley & Sons, Ltd.
Contributions of bedrock groundwater to the upscaling of storm‐runoff generation processes in weathered granitic headwater catchments
Authors: Iwasaki Kenta , Katsuyama Masanori , Tani Makoto
Published: July 2014

We examined the contributions of bedrock groundwater to the upscaling of storm‐runoff generation processes in weathered granitic headwater catchments by conducting detailed hydrochemical observations in five catchments that ranged from zero to second order. End‐member mixing analysis (EMMA) was performed to identify the geographical sources of stream water. Throughfall, hillslope groundwater, shallow bedrock groundwater, and deep bedrock groundwater were identified as end members. The contribution of each end member to storm runoff differed among the catchments because of the differing quantities of riparian groundwater, which was recharged by the bedrock groundwater prior to rainfall events. Among the five catchments, the contribution of throughfall was highest during both baseflow and storm flow in a zero‐order catchment with little contribution from the bedrock groundwater to the riparian reservoir. In zero‐order catchments with some contribution from bedrock groundwater, stream water was dominated by shallow bedrock groundwater during baseflow, but it was significantly influenced by hillslope groundwater during storms. In the first‐order catchment, stream water was dominated by shallow bedrock groundwater during storms as well as baseflow periods. In the second‐order catchment, deeper bedrock groundwater than that found in the zero‐order and first‐order catchments contributed to stream water in all periods, except during large storm events. These results suggest that bedrock groundwater influences the upscaling of storm‐runoff generation processes by affecting the linkages of geomorphic units such as hillslopes, riparian zones, and stream channels. Our results highlight the need for a three‐dimensional approach that considers bedrock groundwater flow when studying the upscaling of storm‐runoff generation processes. Copyright © 2014 John Wiley & Sons, Ltd.
Assessing Outcomes: Practical Methods and Evidence
Authors: Moore Jon , Owen Jesse
Published: July 2014

University counseling center clients’ (N = 52) perceptions of precounseling functioning were highly correlated with their actual well‐being scores at intake. The magnitude of change based on perceptions of precounseling functioning to current well‐being was approximately double of what is found from the difference of actual precounseling well‐being to current well‐being scores. Retrospective methods for assessing precounseling functioning are best suited for comparison among clients or counseling processes.
Racial/Ethnic and Socioeconomic Differences in Bone Loss Among Men
Authors: Araujo Andre B , Yang May , Suarez Elizabeth A , Dagincourt Nicholas , Abraham Jonathan R , Chiu Gretchen , Holick Michael F , Bouxsein Mary L , Zmuda Joseph M
Published: July 2014

As men age, they lose bone and are susceptible to fracture. Despite having lower fracture rates than women, men have worse fractures than women do. Racial/ethnic and socioeconomic status (SES) disparities in fracture rates exist, yet data on rates of bone loss by race/ethnicity and SES among men are limited. We examined annualized percentage change in bone mineral density (%ΔBMD) at the hip (N = 681), spine (N = 663), and forearm (N = 636) during 7 years of follow-up among men aged 30–79 years at baseline. Multivariable models tested whether race/ethnicity, income, or genetic ancestry predicted annualized %ΔBMD after controlling for an extensive set of covariates. Annualized %ΔBMD ranged from −0.65(0.04)% (femoral neck) to +0.26(0.03)% (1/3 distal radius), and changes were consistent across age groups with the exception of the ultradistal radius, where annualized declines increased with age. Neither self-identified race/ethnicity nor genetic ancestry were associated with annualized %ΔBMD. In contrast, income was strongly associated (dose-response) with annualized %ΔBMD at total hip (independent of confounders, self-identified race/ethnicity, and genetic ancestry). Fully adjusted least-square mean change in annualized %ΔBMD at the total hip were −0.24(0.12)% and −0.16(0.06)% steeper among men with low and moderate incomes, respectively, than among men with higher incomes (overall p = 0.0293). Results show a linear decline in bone that begins relatively early in life among men, that rates of bone loss do not vary with race/ethnicity (self-identified or “objectively” measured), and that income plays an important role in relation to bone loss at the hip. These data suggest that fracture risk in men may be driven in part by income-related differences in bone loss, but also, that the known higher fracture risk among white men is not the result of racial/ethnic differences in bone loss, but rather, early life exposures that lead to attainment of higher peak bone mass among minorities. © 2014 American Society for Bone and Mineral Research.
Thiazide-Sensitive Na+-Cl− Cotransporter (NCC) Gene Inactivation Results in Increased Duodenal Ca2+ Absorption, Enhanced Osteoblast Differentiation and Elevated Bone Mineral Density
Authors: Hsu Yu-Juei , Yang Sung-Sen , Cheng Chih-Jen , Liu Shu-Ting , Huang Shih-Ming , Chau Tom , Chu Pauling , Salter Donald M , Lee Herng-Sheng , Lin Shih-Hua
Published: July 2014

Inactivation of the thiazide-sensitive sodium chloride cotransporter (NCC) due to genetic mutations in Gitelman's syndrome (GS) or pharmacological inhibition with thiazide diuretics causes hypocalciuria and increased bone mineral density (BMD) with unclear extrarenal calcium (Ca2+) regulation. We investigated intestinal Ca2+ absorption and bone Ca2+ metabolism in nonsense Ncc Ser707X (S707X) homozygous knockin mice (NccS707X/S707X mice). Compared to wild-type and heterozygous knockin littermates, NccS707X/S707X mice had increased intestinal absorption of 45Ca2+ and expression of the active Ca2+ transport machinery (transient receptor potential vanilloid 6, calbindin-D9K, and plasma membrane Ca2+ ATPase isoform 1b). NccS707X/S707X mice had also significantly increased Ca2+ content accompanied by greater mineral apposition rate (MAR) in their femurs and higher trabecular bone volume, cortical bone thickness, and BMD determined by μCT. Their osteoblast differentiation markers, such as bone alkaline phosphatase, procollagen I, osteocalcin, and osterix, were also significantly increased while osteoclast activity was unaffected. Analysis of marrow-derived bone cells, either treated with thiazide or directly cultured from Ncc S707X knockin mice, showed that the differentiation of osteoblasts was associated with increased phosphorylation of mechanical stress-induced focal adhesion kinase (FAK) and extracellular signal-regulated kinase (ERK). In conclusion, NCC inhibition stimulates duodenal Ca2+ absorption as well as osteoblast differentiation and bone Ca2+ storage, possibly through a FAK/ERK dependent mechanism. © 2014 American Society for Bone and Mineral Research.
Exploring chemical reactivity of complex systems with path‐based coordinates: Role of the distance metric
Authors: Zinovjev Kirill , Tuñón Iñaki
Published: July 2014

Path‐based reaction coordinates constitute a valuable tool for free‐energy calculations in complex processes. When a reference path is defined by means of collective variables, a nonconstant distance metric that incorporates the nonorthonormality of these variables should be taken into account. In this work, we show that, accounting for the correct metric tensor, these kind of variables can provide iso‐hypersurfaces that coincide with the iso‐committor surfaces and that activation free energies equal the value that would be obtained if the committor function itself were used as reaction coordinate. The advantages of the incorporation of the variable metric tensor are illustrated with the analysis of the enzymatic reaction catalyzed by isochorismate‐pyruvate lyase. Hybrid QM/MM techniques are used to obtain the free energy profile and to analyze reactive trajectories initiated at the transition state. For this example, the committor histogram is peaked at 0.5 only when a variable metric tensor is incorporated in the definition of the path‐based coordinate. © 2014 Wiley Periodicals, Inc.
Evidence of plaggen soils in SW Norway
Authors: Schnepel Carolin , Potthoff Kerstin , Eiter Sebastian , Giani Luise
Published: July 2014

This study aimed at clarifying whether a notable group of soils of the Jæren region, SW Norway, with deep humus‐rich top soils support a man‐made genesis. Four sites were investigated. The soils are characterized by thick top soils of 45, 70, 80, and 90 cm, which are enriched in soil organic matter and often also in artifacts, like fragments of potter's clay, indicating an anthropogenic origin. Soil pH ranges from 5.4 to 6.2 (H2O) and 4.4 to 5.3 (CaCl2), respectively. Soil organic C (SOC) contents range from 6.4 to 51.6 g kg−1 and N contents vary between 0 and 2.9 g kg−1. Increased P contents of up to 2,924.3 mg kg−1 total P (Pt) and 1,166.4 mg kg−1 citric acid‐soluble phosphorus (Pc) in the humus‐rich top soils support the assumption of an anthropogenic influence. Although many characteristics indicate an anthropogenic genesis, one soil lacks the required depth of 50 cm of a plaggen horizon and cannot be classified as Plaggic Anthrosol (WRB) and Plagganthrept (US Soil Taxonomy). As the requirement is 40 cm in the German system, all soils can be classified as Plaggenesch. The formation of these soils is related to human activity aiming at increasing soil fertility and overcoming the need of bedding material, the basic aims of the plaggen management in Europe. Highest P contents ever found for this kind of soils and references from the literature indicate that the formation of the soils in Norway started at Viking time, hence, being older than most other Plaggic Anthrosols.
Raman investigation of artificial patinas on recent bronze protected by different azole type inhibitors in an outdoor environment
Authors: Kosec Tadeja , Legat Andraž , Ropret Polonca
Published: July 2014

Bronze surfaces, as well as prepatinated surfaces on bronze, undergo chemical and visual changes when exposed to humid and polluted environments. For this reason, it is important to study the effectiveness of corrosion inhibitors on patinated‐bronze surfaces. The aim of this study was to investigate different protection systems for patinated bronze, which are based on the use of two azole type inhibitors: 2‐mercaptobenzimidazole and benzotriazole. The results of our practice confirmed that these inhibitors were very effective when immersed in a corrosive solution containing inhibitor for 24 h. The inhibited layers were then protected by a water‐repellant layer. In the case of the studied patinas, green chloride and green nitrate patinas, applied over the brown artist's patina, were tested, as well as brown patina and the patina that develops on bare bronze. The study was performed after each chemical patination and the application of the two different inhibitors.

The inhibition systems used on the different chemically achieved patinas were characterized by Raman spectroscopy and electrochemical techniques. The results of the Raman studies showed a chemical interaction of both inhibitors with copper and bronze but a versatile interaction between the inhibitors and the different patinas. The chemical interaction of benzotriazole was observed on the nitrate patina, whereas the mercaptobenzimidazole showed interaction also with the chloride‐type patina. Electrochemical tests proved the interaction, which had been detected by Raman spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd.
Multidisciplinary cancer care: Does it improve outcomes?
Authors: Brar Savtaj S. , Hong Nicole Look , Wright Frances C.
Published: July 2014

Multidisciplinary care has been advocated as a solution for increasingly complex treatment decisions in cancer patients. The impact of multidisciplinary care on patient survival has been studied, but evidence is limited by poor methodological quality. Lack of conclusive evidence for increased survival is balanced against improvements in quality of care, guideline adherence, reduction in wait times, and greater satisfaction for patients and care providers. J. Surg. Oncol. 2014 110:494–499. © 2014 Wiley Periodicals, Inc.
Hybrids of the Benzofuran Core from Natural Products and the 2,4‐Dihydroxy‐5‐isopropylbenzene Fragment as Potent Hsp90 Inhibitors: Design, Synthesis and Bioevaluation
Authors: Jia Jian‐Min , Liu Fang , Xu Xiao‐Li , Guo Xiao‐Ke , Jiang Fen , Huang Hao‐Zhe , Pan Yang , Cherfaoui Bahidja , Sun Hao‐Peng , You Qi‐Dong
Published: July 2014

Several chemical fragments have been confirmed as highly efficient cores for the design of Hsp90 inhibitors. Molecular hybridization of potent fragments has been widely used as a rational drug discovery strategy. In this study, a novel class of hybrids of benzofuran, a privileged core from natural products, and 2,4‐dihydroxy‐5‐isopropyl phenyl, an efficient fragment in Hsp90 inhibitors, were designed and synthesized. Subsequent evaluation confirmed they inhibited cell proliferation and regulated the level of client proteins through Hsp90 inhibition. Some of the hybrids can serve as leads to obtain novel chemotypes of Hsp90 inhibitors. The methods reported here may expand the range of known structural types accommodated by the ATP binding site of Hsp90.
Wave‐CAIPI for highly accelerated 3D imaging
Authors: Bilgic Berkin , Gagoski Borjan A. , Cauley Stephen F. , Fan Audrey P. , Polimeni Jonathan R. , Grant P. Ellen , Wald Lawrence L. , Setsompop Kawin
Published: July 2014

Purpose

To introduce the wave‐CAIPI (controlled aliasing in parallel imaging) acquisition and reconstruction technique for highly accelerated 3D imaging with negligible g‐factor and artifact penalties.

Methods

The wave‐CAIPI 3D acquisition involves playing sinusoidal
and
gradients during the readout of each
encoding line while modifying the 3D phase encoding strategy to incur interslice shifts as in 2D‐CAIPI acquisitions. The resulting acquisition spreads the aliasing evenly in all spatial directions, thereby taking full advantage of 3D coil sensitivity distribution. By expressing the voxel spreading effect as a convolution in image space, an efficient reconstruction scheme that does not require data gridding is proposed. Rapid acquisition and high‐quality image reconstruction with wave‐CAIPI is demonstrated for high‐resolution magnitude and phase imaging and quantitative susceptibility mapping.

Results

Wave‐CAIPI enables full‐brain gradient echo acquisition at 1 mm isotropic voxel size and R = 3 × 3 acceleration with maximum g‐factors of 1.08 at 3T and 1.05 at 7T. Relative to the other advanced Cartesian encoding strategies (2D‐CAIPI and bunched phase encoding) wave‐CAIPI yields up to two‐fold reduction in maximum g‐factor for nine‐fold acceleration at both field strengths.

Conclusion

Wave‐CAIPI allows highly accelerated 3D acquisitions with low artifact and negligible g‐factor penalties, and may facilitate clinical application of high‐resolution volumetric imaging. Magn Reson Med 73:2152–2162, 2015. © 2014 Wiley Periodicals, Inc.
In vivo measurement of gas flow in human airways with hyperpolarized gas MRI and compressed sensing
Authors: Collier Guilhem J. , Wild Jim M.
Published: July 2014

Purpose

Hyperpolarized (HP) 3He and 129Xe are two gases with different fluid dynamic properties, which can be used as tracers for airflow measurement in the lungs with phase contrast velocimetry MRI sequences. In this work, in vivo measurements of velocity maps of airflow in the upper airways and first bronchi of healthy volunteers were obtained with both gases and compared.

Theory and Methods

To reduce the acquisition time, a Compressed Sensing (CS) based acquisition and reconstruction algorithm was developed and optimized for flow measurement in three directions by including the sparsity of the complex difference images as prior knowledge.

Results

CS simulations on retrospectively under‐sampled images demonstrated a better reconstruction with the inclusion of the complex difference terms in the cost function. The technique was then validated with a prospective acquisition study providing artifact free maps with acceleration factors up to 3.

Conclusion

The presented technique opens up the possibility to map velocity inside human lungs. The results are of interest for the validation of computational fluid dynamics flow simulations and for understanding the spatio‐temporal evolution of airflow patterns in the airways in vivo with different gas mixtures. Magn Reson Med 73:2255–2261, 2015. © 2014 Wiley Periodicals, Inc.
Cortical depth dependence of the BOLD initial dip and poststimulus undershoot in human visual cortex at 7 Tesla
Authors: Siero Jeroen C.W. , Hendrikse Jeroen , Hoogduin Hans , Petridou Natalia , Luijten Peter , Donahue Manus J.
Published: July 2014

Purpose

Owing to variability in vascular dynamics across cerebral cortex, blood‐oxygenation‐level‐dependent (BOLD) spatial and temporal characteristics should vary as a function of cortical‐depth. Here, the positive response, initial dip (ID), and post‐stimulus undershoot (PSU) of the BOLD response in human visual cortex are investigated as a function of cortical depth and stimulus duration at 7 Tesla (T).

Methods

Gradient‐echo echo‐planar‐imaging BOLD fMRI with high spatial and temporal resolution was performed in 7 healthy volunteers and measurements of the ID, PSU, and positive BOLD response were made as a function of cortical depth and stimulus duration (0.5–8 s). Exploratory analyses were applied to understand whether functional mapping could be achieved using the ID, rather than positive, BOLD signal characteristics

Results

The ID was largest in outer cortical layers, consistent with previously reported upstream propagation of vasodilation along the diving arterioles in animals. The positive BOLD signal and PSU showed different relationships across the cortical depth with respect to stimulus duration.

Conclusion

The ID and PSU were measured in humans at 7T and exhibited similar trends to those recently reported in animals. Furthermore, while evidence is provided for the ID being a potentially useful feature for better understanding BOLD signal dynamics, such as laminar neurovascular coupling, functional mapping based on the ID is extremely difficult. Magn Reson Med 73:2283–2295, 2015. © 2014 Wiley Periodicals, Inc.
Mit Tetraedern zum Ziel
Authors: Heine Johanna , Weinert Bastian , Dehnen Stefanie
Published: July 2014

Multinäre Metallate und intermetalloide Cluster zeigen eine große Vielfalt bei Strukturen und Reaktivitätsmustern. Binäre, tetraedrische Hauptgruppenelement‐Anionen bieten einen effizienten Zugang zu solchen aus drei und mehr Elementen aufgebauten anorganischen Materialien.
Dreidimensionales wächst
Authors: Gottwald Eric , Haug Peter , Truckenmüller Roman
Published: July 2014

Dreidimensionale Zellmodelle bilden die Situation im lebenden Organismus besser ab als zweidimensionale; sie eignen sich aber häufig nicht für Hochdurchsatzverfahren. Neue 3‐D‐Systeme mit fixierter Position der Zellen könnten dies ändern.
Elektrochemischer Nitratsensor
Authors: Plumeré Nicolas
Published: July 2014

Der Stickstoffbedarf von Nutzpflanzen ist bekannt und der Nitratgehalt im Boden analytisch quantifizierbar, sodass Landwirte die Menge an Düngemittel dem Bedarf anpassen könnten. Sie schrecken jedoch vor den für sie aufwendigen Bodenanalysen zurück und setzen Düngemittel im Überschuss ein. Abhilfe schaffen auf dem Feld einsetzbare Testsysteme mit elektrochemischen Sensoren.
Hilft Uniluft‐Schnuppern gegen Studienabbruch?
Authors: Engel Thomas
Published: July 2014

Seit dem Jahr 2006 wählt die Ludwig‐Maximilians‐Universität München Bewerber für den Bachelorstudiengang “Chemie und Biochemie” anhand gewichteter Schulnoten. Seit 2008 überprüfen Studieninteressierte zudem in einem Praktikum vor der Immatrikulation theoretische Kenntnisse sowie praktische Fertigkeiten. Sind durch die beiden Maßnahmen die Studienabbrüche zurückgegangen?
Inventory control and replenishment with flexible delivery‐time upgrade
Authors: Liang Xiaoying , Yan Houmin
Published: July 2014

We consider a capacitated inventory model with flexible delivery upgrades, in which the seller allocates its on‐hand inventory to price‐ and delivery‐time‐sensitive customers. The seller has two decisions: inventory commitment and replenishment. The former addresses how the on‐hand inventories are allocated between the two classes of customers within an inventory cycle. The latter addresses how the inventory is replenished between inventory cycles. We develop optimal inventory allocation, upgrade, and replenishment policies and demonstrate that the optimal policy can be characterized by a set of switching curves. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 418–426, 2014
Oxygen‐enhanced 3D radial ultrashort echo time magnetic resonance imaging in the healthy human lung
Authors: Kruger Stanley J. , Fain Sean B. , Johnson Kevin M. , Cadman Robert V. , Nagle Scott K.
Published: July 2014

The purpose of this work was to use 3D radial ultrashort echo time (UTE) MRI to perform whole‐lung oxygen‐enhanced (OE) imaging in humans.

Eight healthy human subjects underwent two 3D radial UTE MRI acquisitions (TE = 0.08 ms): one while breathing 21% O2 and the other while breathing 100% O2. Scans were each performed over 5 min of free breathing, using prospective respiratory gating. For comparison purposes, conventional echo time (TE = 2.1 ms) images were acquired simultaneously during each acquisition using a radial " outward‐inward" k‐space trajectory. 3D percent OE maps were generated from these images.

3D OE maps showing lung signal enhancement were generated successfully in seven subjects (technical failure in one subject). Mean percent signal enhancement was 6.6% ± 1.8%, near the value predicted by theory of 6.3%. No significant enhancement was seen using the conventional echo time data, confirming the importance of UTE for this acquisition strategy.

3D radial UTE MRI shows promise as a method for OE MRI that enables whole‐lung coverage and isotropic spatial resolution, in comparison to existing 2D OE methods, which rely on a less time‐efficient inversion recovery pulse sequence. These qualities may help OE MRI become a viable low‐cost method for 3D imaging of lung function in human subjects. Copyright © 2014 John Wiley & Sons, Ltd.
Multigrid‐in‐time for sensitivity analysis of chaotic dynamical systems
Authors: Blonigan Patrick , Wang Qiqi
Published: July 2014

The following paper discusses the application of a multigrid‐in‐time scheme to Least Squares Shadowing (LSS), a novel sensitivity analysis method for chaotic dynamical systems. While traditional sensitivity analysis methods break down for chaotic dynamical systems, LSS is able to compute accurate gradients. Multigrid is used because LSS requires solving a very large Karush–Kuhn–Tucker system constructed from the solution of the dynamical system over the entire time interval of interest. Several different multigrid‐in‐time schemes are examined, and a number of factors were found to heavily influence the convergence rate of multigrid‐in‐time for LSS. These include the iterative method used for the smoother, how the coarse grid system is formed and how the least squares objective function at the center of LSS is weighted.
Thermodynamically consistent algorithms for a finite‐deformation phase‐field approach to fracture
Authors: Hesch C. , Weinberg K.
Published: July 2014

Phase‐field approaches to fracture offer new perspectives toward the numerical solution of crack propagation. In this paper, a phase‐field method for finite deformations and general nonlinear material models is introduced using a novel multiplicative split of the principal stretches to account for the different behavior of fracture in tension and compression. An energy‐momentum consistent integrator is developed and applied to the arising nonlinear coupled phase‐field model. This approach is thermodynamically consistent in the sense that the first law of thermodynamics if fulfilled with respect to the dissipation function. The capabilities and the performance of the proposed approach is demonstrated in several representative examples. Copyright © 2014 John Wiley & Sons, Ltd.
A massively parallel implementation of the Optimal Transportation Meshfree method for explicit solid dynamics
Authors: Li B. , Stalzer M. , Ortiz M.
Published: July 2014

Presented is a massively parallel implementation of the Optimal Transportation Meshfree (pOTM) method Li et al., 2010 for explicit solid dynamics. Its implementation is based on a two‐level scheme using Message Passing Interface between compute servers and threaded parallelism on the multi‐core processors within each server. Both layers dynamically subdivide the problem to provide excellent parallel scalability. pOTM is used on three problems and compared to experiments to demonstrate accuracy and performance. For both a Taylor‐anvil and a hypervelocity impact problem, the pOTM implementation scales nearly perfectly to about 8000 cores. Copyright © 2014 John Wiley & Sons, Ltd.
Comparison of the Effects of Combination Diuretic Therapy with Oral Hydrochlorothiazide or Intravenous Chlorothiazide in Patients Receiving Intravenous Furosemide Therapy for the Treatment of Heart Failure
Authors: Kissling Kevin T. , Pickworth Kerry K.
Published: July 2014

Study Objective

To compare the effects of combination diuretic therapy with oral hydrochlorothiazide or intravenous chlorothiazide added to background intravenous loop diuretic therapy among patients hospitalized with heart failure.

Design

Single‐center, retrospective review.

Setting

Cardiovascular hospital within a university‐affiliated teaching institution.

Patients

Eighty‐two patients hospitalized for heart failure between September 1, 2009, and August 31, 2011, who were receiving background intravenous furosemide therapy (total daily dose ≥ 160 mg); of those patients, 28 patients also received oral hydrochlorothiazide (median dose 25 mg [interquartile range 25–50 mg]), and 54 patients also received intravenous chlorothiazide (median dose 500 mg [interquartile range 250–750 mg]).

Measurements and Main Results

The primary outcome was change in 24‐hour urine output. Urine output was recorded from the 24 hours before and after the first administration of either oral hydrochlorothiazide or intravenous chlorothiazide. Baseline characteristics, with the exception of female sex (p=0.01) and home loop diuretic dose (p=0.03), were similar between groups. Twenty‐four–hour urine output before administration of the thiazide diuretic was not significantly different between groups. After treatment, 24‐hour urine output increased in both groups; however, urine output increased to a lesser extent with oral hydrochlorothiazide (from mean ± SD 2104 ± 830 ml to 3038 ± 917 ml) than with intravenous chlorothiazide (from 2342 ± 978 ml to 4128 ± 1755 ml) (p=0.005). Hypokalemia occurred frequently in both groups: 71.4% and 83.3% in the oral hydrochlorothiazide and intravenous chlorothiazide groups, respectively (p=0.21).

Conclusion

Among hospitalized patients with heart failure receiving intravenous loop diuretics, the addition of either oral hydrochlorothiazide or intravenous chlorothiazide augmented diuresis. Urine output increased to a greater extent with intravenous chlorothiazide compared with oral hydrochlorothiazide. However, given the positive response observed, ease of administration, and lower drug cost, oral hydrochlorothiazide should still be considered as an option for combination diuretic therapy in this patient population.
Teilchendynamik fern vom Gleichgewicht
Authors: Liebchen Benno , Schmelcher Peter
Published: July 2014

Fern des thermodynamischen Gleichgewichts kann ungerichtete Bewegung sogar auf atomaren Skalen in gerichtete Bewegung umgewandelt werden. Dieses Phänomen nutzen biologische Organismen seit Urzeiten. Angesichts der beachtlichen Fortschritte der Nanotechnologie und der Miniaturisierung elektronischer Bauteile rücken gerichtete Teilchenströme aber auch zunehmend in den Fokus von Wissenschaft und Technik. Neue Wege zur Kontrolle von Teilchen und gerichteten Teilchenströmen bieten raumzeitlich getriebene Gitter. Insbesondere ermöglichen sie das Sortieren von Teilchen in Mustern und den Transport ganzer Dichtewellen. Teilchen, die untereinander wechselwirken, wie etwa Ionen, zeigen eine nahezu kollektive Konversion von Chaos zu Ordnung. Diese äußert sich in einer überraschenden, selbstständigen Umkehr der Richtung von Teilchenströmen.
ScreenCap3: Improving prediction of caspase‐3 cleavage sites using experimentally verified noncleavage sites
Authors: Fu Szu‐Chin , Imai Kenichiro , Sawasaki Tatsuya , Tomii Kentaro
Published: July 2014

Because of its wide range of substrates, caspase‐3, a main executioner among apoptosis‐related caspases, is thought to have many unknown substrates that have remained unidentified. This report describes our predictive method to facilitate the discovery of novel caspase‐3 substrates. To develop a more reliable prediction method, we specifically examined improvement of the data quantity and quality of caspase‐3 cleavage sites. The ScreenCap3 method is based on machine learning and on information not only of experimentally verified positive examples but also of negative examples, which were not cleaved by caspase‐3. Using information of experimentally verified noncleavage sites, we elucidate novel patterns of amino acids around “actual” cleavage sites. Results show that ScreenCap3 provides substantial improvement in terms of precision, compared with existing methods. Therefore, ScreenCap3 is anticipated for use with proteomic screening and identification of novel caspase‐3 substrates and their cleavage sites. ScreenCap3 is available at http://scap.cbrc.jp/ScreenCap3/.
Role of gemini surfactants (m‐s‐m type; m = 16, s = 4–6) on the reaction of [Zn(II)‐Gly‐Phe]+ with ninhydrin
Authors: Kumar Dileep , Rub Malik Abdul , Akram Mohd. , Kabir‐ud‐Din
Published: July 2014

In the present paper, reaction of zinc‐glycylphenylalanine ([Zn(II)‐Gly‐Phe]+) with ninhydrin has been investigated in gemini (m‐s‐m type; m = 16, s = 4–6) surfactants at temperature (70 °C) and pH (5.0). Monitoring the appearance of product at 400 nm was used to follow the kinetics, spectrophotometrically. The order of the reaction with respect to [Zn(II)‐Gly‐Phe]+ was unity while with respect to [ninhydrin] was fractional. The reaction constants involved in the mechanism were obtained. In addition to the rate constant (kΨ) increase and leveling‐off regions are observed with the geminis, just like as seen with conventional surfactant hexadecyltrimethylammonium bromide (CTAB), the former produced a third region of increasing kΨ at higher concentrations. A close agreement between observed and calculated rate constants was found under varying experimental conditions. A suitable mechanism consistent with the experimental findings has been proposed. Copyright © 2014 John Wiley & Sons, Ltd.
A High‐Performance Anode Material for Li‐Ion Batteries Based on a Vertically Aligned CNTs/NiCo2O4 Core/Shell Structure
Authors: Liu Wenwen , Lu Congxiang , Liang Kun , Tay Beng Kang
Published: July 2014

3D vertically aligned carbon nanotubes (CNTs)/NiCo2O4 core/shell structures are successfully synthesized as binder‐free anode materials for Li‐ion batteries (LIBs) via a facile electrochemical deposition method followed by subsequent annealing in air. The vertically aligned CNTs/NiCo2O4 core/shell structures are used as binder‐free anode materials for LIBs and exhibit high and stable reversible capacity (1147.6 mAhg−1 at 100 mAg−1), excellent rate capability (712.9 mAh g−1 at 1000 mAg−1), and good cycle stability (no capacity fading over 200 cycles). The improved performance of these LIBs is attributed to the unique 3D vertically aligned CNTs/NiCo2O4 core/shell structures, which support high electron conductivity, fast ion/electron transport in the electrode and at the electrolyte/electrode interface, and accommodate the volume change during cycling. Furthermore, the synthetic strategy presented can be easily extended to fabricate other metal oxides with a controlled core/shell structure, which may be a promising electrode material for high‐performance LIBs.
Revisiting the structure of the Vps10 domain of human sortilin and its interaction with neurotensin
Authors: Quistgaard Esben M. , Grøftehauge Morten K. , Madsen Peder , Pallesen Lone T. , Christensen Brian , Sørensen Esben S. , Nissen Poul , Petersen Claus M. , Thirup Søren S.
Published: July 2014

Sortilin is a multifunctional receptor involved in sorting and apoptosis. We have previously reported a 2.0‐Å structure of the Vps10 ectodomain in complex with one of its ligands, the tridecapeptide neurotensin. Here we set out to further characterize the structural properties of sortilin and its interaction with neurotensin. To this end, we have determined a new 2.7 Å structure using a crystal grown with a 10‐fold increased concentration of neurotensin. Here a second peptide fragment was observed within the Vps10 β‐propeller, which may in principle either represent a second molecule of neurotensin or the N‐terminal part of the molecule bound at the previously identified binding site. However, in vitro binding experiments strongly favor the latter hypothesis. Neurotensin thus appears to bind with a 1:1 stoichiometry, and whereas the N‐terminus does not bind on its own, it enhances the affinity in context of full‐length neurotensin. We conclude that the N‐terminus of neurotensin probably functions as an affinity enhancer for binding to sortilin by engaging the second binding site. Crystal packing differs partly from the previous structure, which may be due to variations in the degree and pattern of glycosylations. Consequently, a notable hydrophobic loop, not modeled previously, could now be traced. A computational analysis suggests that this and a neighboring loop may insert into the membrane and thus restrain movement of the Vps10 domain. We have, furthermore, mapped all N‐linked glycosylations of CHO‐expressed human sortilin by mass spectrometry and find that their locations are compatible with membrane insertion of the hydrophobic loops.
Introducing touchstroke: keystroke‐based authentication system for smartphones
Authors: Kambourakis Georgios , Damopoulos Dimitrios , Papamartzivanos Dimitrios , Pavlidakis Emmanouil
Published: July 2014

Keystroke dynamics is a well‐investigated behavioural biometric based on the way and rhythm in which someone interacts with a keyboard or keypad when typing characters. This paper explores the potential of this modality but for touchscreen‐equipped smartphones. The main research question posed is whether ‘touchstroking’ can be effective in building the biometric profile of a user, in terms of typing pattern, for future authentication. To reach this goal, we implemented a touchstroke system in the Android platform and executed different scenarios under disparate methodologies to estimate its effectiveness in authenticating the end‐user. Apart from typical classification features used in legacy keystroke systems, we introduce two novel ones, namely, speed and distance. From the experiments, it can be argued that touchstroke dynamics can be quite competitive, at least when compared to similar results obtained from keystroke evaluation studies. As far as we are aware of, this is the first time this newly arisen behavioural trait is put into focus. Copyright © 2014 John Wiley & Sons, Ltd.
A modeling methodology to facilitate safety‐oriented architecture design of industrial avionics software
Authors: Wu Ji , Yue Tao , Ali Shaukat , Zhang Huihui
Published: July 2014

Ensuring that avionics software meets safety requirements at each development stage is very important to warrant the safe operation of an avionics system. Many safety requirements are imposed by various standards and industrial regulations that must be met by avionics software. One of such standards is DO‐178B/C, which provides guidelines (e.g., development process and objectives to satisfy in development activities) for meeting safety requirements. This paper presents a modeling methodology including a UML profile for specifying safety requirements on a component‐based architecture model and a set of design guidelines on avionics software. These safety requirements were identified from both standards (mainly DO‐178B/C) and current engineering practices in the domain of avionics systems. The methodology automatically enforces these safety requirements. We have applied the methodology on an industrial autopilot system, and several previously uncaught faults were revealed. Copyright © 2014 John Wiley & Sons, Ltd.
Numerical Study about the Influence of Small Casting Speed Variations on the Metallurgical Length in Continuous Casting of Steel Slabs
Authors: Domitner Josef , Wu Menghuai , Ludwig Andreas
Published: July 2014

Numerical simulations are prepared to investigate the influence of small casting speed variations between 715 and 735 mm min−1 on the metallurgical length in continuous casting of 285 mm thick steel slabs. The effect of considering/ignoring the melt flow in the numerical continuous casting model for predicting the metallurgical length is also investigated. The simulations are based on an Eulerian two‐phase solidification model including melt (liquid phase) and columnar dendrites (solid phase). Solidification of a binary Fe–C‐alloy is calculated. Two 25 m long straight strand geometries of industrial scale are modeled. Both of these geometries have waved surfaces to consider periodical strand surface bulging. In order to consider a defined mechanical softreduction (MSR) configuration as well, the cross‐section of one of these geometries decreases at a rate of 1 mm m−1 within a defined length. For a given casting configuration and for defined cooling conditions, the influence of small casting speed variations on the metallurgical length, on the average solid fraction and on the enthalpy flux are determined. The simulation results can be used to optimize the settings for operating continuous casting plants, e.g., to adapt the MSR position.
Effects of secondary electron emission coefficients on Townsend's second ionization coefficient in argon dielectric barrier discharges
Authors: Yoshinaga Tomokazu , Akashi Haruaki
Published: July 2014

One‐dimensional fluid model simulations are performed to investigate how the secondary electron emission arising from ions (γi), metastable atoms (γm), and photons (γp) affect Townsend's second ionization coefficient (γ′) in argon dielectric barrier discharges. Since Townsend's breakdown criterion determines the value of γ′, it is naturally affected by the discharge condition such as the reduced electric field (E/p) as well as the combination of γi, γm, and γp. It also depends on the other contributions from the indirect ionization processes such as cumulative ionizations or metastable–metastable collision ionizations. When the nonionic electron‐yielding processes such as the effects of γm, γp, and the indirect ionizations are considered, the calculated γ′ increases largely under the higher pd (pressure times distance) branch of the Paschen curve. Since the experimental characteristics of γ′, which decreases with E/p, can hardly be explained without such nonionic processes, the contributions of those processes can be quite important in Townsend discharges especially under high pd conditions. These processes tend not to appear and γ′ tends to converge to γi under the lower pd branch of the Paschen curve. The value of γi can possibly be estimated by using γ′ under the lower pd condition. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Unitary coherent strategy for spatial sparsity‐based DOA estimation of wideband signals
Authors: Kahaei Mohammad Hossein , Atashbar Mahmoud
Published: July 2014

The coherent l1‐singular value decomposition (l1‐SVD) uses a non‐unitary coherent strategy for transferring different frequency bin data to a reference bin, which decreases the signal‐to‐error ratio (SER) in transferring, thereby leading to a decrease in accuracy in the direction of arrival (DOA) estimation. To cope with this problem, in this paper we propose a unitary coherent strategy that uses unitary focusing matrices for transferring data. Simulation results show that the proposed method outperforms the coherent l1‐SVD method in accurate DOA estimation. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.