bluuebunny/crossref_metadata_2025_split huggingface dataset:
MR safety: Fast T1 thermometry of the RF‐induced heating of medical devices
Authors: Gensler D. , Fidler F. , Ehses P. , Warmuth M. , Reiter T. , Düring M. , Ritter O. , Ladd M. E. , Quick H. H. , Jakob P. M. , Bauer W. R. , Nordbeck P. 
Published: January 2012

AbstractDetermining the MR compatibility of medical implants and devices is becoming increasingly relevant. In most cases, the heating of conductive implants due to radiefrequency (RF) excitation pulses is measured by fluoroptic temperature sensors in relevant tests for approval. Another common method to determine these heating effects is MR thermometry using the proton resonance frequency. This method gives good results in homogeneous phantoms. However in many cases, technical shortcomings such as susceptibility artifacts prohibit exact proton resonance frequency thermometry near medical implants. Therefore, this work aimed at developing a fast T1‐based method which allows controlled MR‐related heating of a medical implant while simultaneously quantifying the spatial and temporal temperature distribution. To this end, an inversion recovery snapshot Fast Low‐Angle Shot (FLASH) sequence was modified with additional off‐resonant heating pulses. With an accelerated imaging method and a sliding‐window technique, every 7.6 s a new temperature map could be generated with a spatial in‐plane resolution of 2 mm. The temperature deviation from calculated temperature values to reference fluoroptic probe was found to be smaller than 1 K. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Informed RESTORE: A method for robust estimation of diffusion tensor from low redundancy datasets in the presence of physiological noise artifacts
Authors: Chang Lin‐Ching , Walker Lindsay , Pierpaoli Carlo 
Published: January 2012

AbstractPhysiological noise artifacts, especially those originating from cardiac pulsation and subject motion, are common in clinical Diffusion tensor‐MRI acquisitions. Previous works show that signal perturbations produced by artifacts can be severe and neglecting to account for their contribution can result in erroneous diffusion tensor values. The Robust Estimation of Tensors by Outlier Rejection (RESTORE) method has been shown to be an effective strategy for improving tensor estimation on a voxel‐by‐voxel basis in the presence of artifactual data points in diffusion‐weighted images. In this article, we address potential instabilities that may arise when using RESTORE and propose practical constraints to improve its usability. Moreover, we introduce a method, called informed RESTORE designed to remove physiological noise artifacts in datasets acquired with low redundancy (less than 30–40 diffusion‐weighted image volumes)—a condition in which the original RESTORE algorithm may converge to an incorrect solution. This new method is based on the notion that physiological noise is more likely to result in signal dropouts than signal increases. Results from both Monte Carlo simulation and clinical diffusion data indicate that informed RESTORE performs very well in removing physiological noise artifacts for low redundancy diffusion‐weighted image datasets. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Microscopic diffusion anisotropy in formalin fixed prostate tissue: Preliminary findings
Authors: Bourne Roger M. , Kurniawan Nyoman , Cowin Gary , Sved Paul , Watson Geoffrey 
Published: January 2012

AbstractDiffusion tensor microimaging at 16.4 T with 40 μm isotropic voxels was used to investigate anisotropic water diffusion in prostate tissue at spatial resolution approaching the cellular scale. Nine normal glandular tissue samples were collected from the peripheral zone of six formalin fixed radical prostatectomy specimens. Fibromuscular stromal tissue exhibited microscopic diffusion anisotropy (mean fractional anisotropy range 0.47–0.66) significantly higher (P < 0.01, Student's t‐test) than in epithelium‐containing voxels (mean fractional anisotropy range 0.31–0.54) in six of the seven normal tissue samples in which both compartments could be measured. Fiber tracking demonstrated principle stromal fiber directions consistent with myocyte orientation seen on light microscopy of the same sample. Diffusion tensor microimaging may be valuable for investigation of variable results from attempts to measure diffusion anisotropy in the prostate in vivo. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Cohesive and non‐cohesive fracture by higher‐order enrichment of XFEM
Authors: Zamani Arash , Gracie Robert , Reza Eslami M. 
Published: January 2012

SUMMARYA comprehensive study is performed on the use of higher‐order terms of the crack tip asymptotic fields as enriching functions for the eXtended FEM (XFEM) for both cohesive and traction‐free cracks. For traction‐free cracks, the Williams asymptotic field is used to obtain highly accurate stress intensity factors (SIFs), directly from the enriched degrees of freedom without any post‐processing. The low accuracy of the results of the original research on this subject by Liu et al. [Int. J. Numer. Meth. Engng., 2004; 59:1103–1118] is remedied here by appropriate modifications of the enrichment scheme. The modifications are simple and can be easily included into an XFEM computer code. For cohesive cracks, the relevant asymptotic field is used, and two widely used criteria including the SIFs criterion and the stress criterion are examined for the crack growth simulation. Both linear and nonlinear cohesive laws are used. For the stress criterion, averaging is avoided due to the highly accurate crack tip approximation because of the higher‐order enrichment. Then, a modified stress criterion is proposed, which is shown to be applicable to a wider class of problems. Several numerical examples, including straight and curved cracks, stationary and growing cracks, single and multiple cracks, and traction‐free and cohesive cracks, are studied to investigate in detail the robustness and efficiency of the proposed enrichment scheme. Copyright © 2012 John Wiley & Sons, Ltd.
Glucocorticoid regulation of a novel HPV–E6–p53–miR‐145 pathway modulates invasion and therapy resistance of cervical cancer cells
Authors: Shi Ming , Du Libin , Liu Dan , Qian Lu , Hu Meiru , Yu Ming , Yang Zhengyan , Zhao Mingzhen , Chen Changguo , Guo Liang , Wang Lina , Song Lun , Ma Yuanfang , Guo Ning 
Published: January 2012

AbstractGlucocorticoids are stress‐responsive neuroendocrine mediators and play an important role in malignant progression, especially in solid tumours. We demonstrate a novel mechanism by which glucocorticoids modulate p53‐dependent miR‐145 expression in HPV‐positive cervical cancer cells through induction of E6 proteins. We found that expression of miR‐145 was reduced in cervical cancer tissues. Cortisol induced HPV‐E6 expression and suppressed p53 and miR‐145 in cervical cancer cells. MiR‐145 expression in cervical cancer cells was wild‐type p53‐dependent, and cortisol‐induced down‐regulation of miR‐145 expression prevented chemotherapy‐induced apoptosis, whereas over‐expression of miR‐145 enhanced sensitivity to mitomycin and reversed the chemoresistance induced by glucocorticoids. We also show that miR‐145 augments the effects of p53 by suppressing the inhibitors of p53 in cervical cancer cells, suggesting that miR‐145 plays a role in p53 tumour suppression. Finally, we demonstrate that miR‐145 inhibits both the motility and invasion of cervical cancer cells. Our findings identify a novel pathway through which the neuroendocrine macroenvironment affects cervical tumour growth, invasion and therapy resistance and show that miR‐145 may serve as a target for cervical cancer therapy. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Predictive factors of internalized and externalized behavioral problems in children treated for acute lymphoblastic leukemia
Authors: Marcoux Sophie , Robaey Philippe , Krajinovic Maja , Moghrabi Albert , Laverdière Caroline 
Published: January 2012

AbstractBackgroundPediatric cancer survivors are at increased risk of various neurological and psychological problems. The prevalence of behavioral problems was assessed in a longitudinal study in pediatric patients with an acute lymphoblastic leukemia (ALL). Multilevel modeling was used to identify associated predictive factors.ProcedureALL patients and their parents (n = 138) took part to this study. Patients were treated according to the Dana‐Farber Cancer Institute (DFCI) consortium protocols 91‐01 or 95‐01. Mothers filled out questionnaires providing a measure of behavioral problems for their child at diagnosis and during the subsequent 4 years, and of their perceived familial stress at diagnosis and post‐induction.ResultsPrevalence of internalized behavioral problems at diagnosis was increased [42% above 1 standard deviation (SD); P < 0.001], but it normalized over time. Internalized problems resolved more slowly in the presence of medical variables associated with increased stress related to the disease (hospitalization duration, P < 0.001; relapse risk at diagnosis, P < 0.001). Externalized behavioral problems were within the expected normal range, but more sustained over time with the 95‐01 than with the 91‐01 treatment protocols (P < 0.05), likely due to the type of corticosteroid (CS) used (dexamethasone vs. prednisone).ConclusionsAssessment of both internalized and externalized problems is required in this population. The impact of pharmacological variables on externalized behavioral problems is likely related to CS use. Pediatr Blood Cancer 2012; 58: 971–977. © 2012 Wiley Periodicals, Inc.
Generalised geometry and type II supergravity
Authors: Coimbra A. , Strickland‐Constable C. , Waldram D. 
Published: January 2012

AbstractTen‐dimensional type II supergravity can be reformulated as a generalised geometrical analogue of Einstein gravity, defined by an O(9,1) × O(1,9) ⊂ O(10,10) × ℝ+ structure on the generalised tangent space. To leading order in the fermion fields, this allow one to rewrite the action, equations of motion and supersymmetry variations in a simple, manifestly Spin(9,1) × Spin(1,9)‐covariant form.
Vacua analysis in extended supersymmetry compactifications
Authors: Dibitetto G. , Guarino A. , Roest D. 
Published: January 2012

AbstractWe analyse geometric type IIA flux compactifications leading to 𝒩 = 4 gauged supergravities in four dimensions. The complete landscape of isotropic vacua is presented, which turns out to belong to a unique theory. The solutions admit an uplift to maximal supergravity due to the vanishing of the flux‐induced tadpoles for all the supersymmetry‐breaking branes. Such an uplift is sketched out and the full 𝒩 = 8 mass spectra are discussed. We find the interesting presence of a non‐supersymmetric and nevertheless stable minimum.
Structural features that predict real‐value fluctuations of globular proteins
Authors: Jamroz Michal , Kolinski Andrzej , Kihara Daisuke 
Published: January 2012

AbstractIt is crucial to consider dynamics for understanding the biological function of proteins. We used a large number of molecular dynamics (MD) trajectories of nonhomologous proteins as references and examined static structural features of proteins that are most relevant to fluctuations. We examined correlation of individual structural features with fluctuations and further investigated effective combinations of features for predicting the real value of residue fluctuations using the support vector regression (SVR). It was found that some structural features have higher correlation than crystallographic B‐factors with fluctuations observed in MD trajectories. Moreover, SVR that uses combinations of static structural features showed accurate prediction of fluctuations with an average Pearson's correlation coefficient of 0.669 and a root mean square error of 1.04 Å. This correlation coefficient is higher than the one observed in predictions by the Gaussian network model (GNM). An advantage of the developed method over the GNMs is that the former predicts the real value of fluctuation. The results help improve our understanding of relationships between protein structure and fluctuation. Furthermore, the developed method provides a convienient practial way to predict fluctuations of proteins using easily computed static structural features of proteins. Proteins 2012; © 2012 Wiley Periodicals, Inc.
Evidence of induced structural and conduction anisotropy in scandia‐stabilized zirconia ceramics
Authors: Barbashov Vladimir , Nesova Elizaveta , Pismenova Natalia , Radionova Olga 
Published: January 2012

AbstractEvidence of current induced structural and conduction anisotropy was experimentally established in scandia‐stabilized zirconia ceramics. It was found that these effects are observed only when the material is in the rhombohedral phase. It was shown using conductivity measurements and X‐ray phase analysis that anisotropic behavior of polycrystalline ZrO2‐Sc2O3 ceramics is induced by a low‐amplitude alternating current in the temperature range corresponding to a rhombohedral‐to‐cubic phase transition.
Light extraction improvement by forming volcanic crater on N‐polar GaN emitting surface
Authors: Chang You‐Hsien , Yang Chun‐Ting , Liu Cheng‐Yi 
Published: January 2012

AbstractBy lifting‐off the patterned sapphire substrate of flip‐chip GaN‐based light emitting diodes, a 2‐D periodic pattern of inverted circular cavities was created on the N‐polar GaN (N‐GaN) surface. The inverted circular cavities on the N‐GaN surface evolve to discrete volcanic craters by wet etching in hot KOH solution. The formation of volcanic craters greatly enhances the light extraction efficiency on the patterned GaN surface by 27%. In addition, a correlation is observed between the threading dislocation distribution and the etching pattern on the N‐GaN surface, which implies that the threading dislocation seemingly guides the etching on the N‐GaN surface. A dislocation‐orientated etching mechanism on the N‐GaN surface is proposed in this study.
Piezoelectric properties of PbHfO3–PbTiO3–Pb(Mg1/3Nb2/3)O3 ternary ceramics
Authors: Wang Dawei , Cao Maosheng , Zhang Shujun 
Published: January 2012

Abstract(1 – x)Pb(Hf1–yTiy)O3–x Pb(Mg1/3Nb2/3)O3 (x = 0.1 ∼ 0.25, y = 0.555) ternary piezoelectric ceramics were prepared using the two‐step precursor method. Morphotropic phase boundary (MPB) compositions, located at x = 0.18 ∼ 0.22, were confirmed using X‐ray diffraction and by their dielectric, piezoelectric and ferroelectric properties. The optimum dielectric and piezoelectric properties were achieved for the MPB composition 0.8Pb(Hf0.445Ti0.555)O3–0.2Pb(Mg1/3Nb2/3)O3, with dielectric permittivity εr, piezoelectric coefficient d33, planar electromechanical coupling kp and Curie temperature TC being on the order of 2800, 680 pC/N, 70% and 276 °C, respectively. Of particular significance is that the new ternary ceramics exhibit comparable piezoelectric and electromechanical properties to commercial PZT5H ceramics, but with much improved TC, showing a potential for applications at elevated temperature. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐linearity cannot help RFID resist full‐disclosure attacks and terrorist fraud attacks
Authors: Chien Hung‐Yu , Yang Chu‐Sing , Hou Hung‐Pin 
Published: January 2012

ABSTRACTAs the concept of radio‐frequency identification (RFID) relay attack has been successfully implemented and demonstrated, the research of RFID distance‐bounding protocols to deter RFID relay attacks has drawn much attention from both the industry and academia. Conventionally, researchers adopted linear composition of secrets to resist terrorist fraud attacks. Recently, Peris‐Lopez et al. studied the weaknesses of previous RFID distance‐bounding protocols and proposed that non‐linear composition of secrets and inclusion of more random nonce could help RFID resist key disclosure attack and terrorist fraud attack. In this paper, we will show that non‐linear composition of secrets cannot help enhance the security actually. Copyright © 2012 John Wiley & Sons, Ltd.
XFPM‐RBAC: XML‐based specification language for security policies in multidomain mobile networks
Authors: Unal Devrim , Caglayan M. Ufuk 
Published: January 2012

ABSTRACTWe present XFPM‐RBAC (XML‐based formal policy language for mobility with role‐based access control), an XML‐based specification language for specification of domain and interdomain security policies with location and mobility constraints based on role‐based access control. XFPM‐RBAC supports specification of locations, mobility, interdomain access rights, role mapping, and separation of duty (SOD) aspects of security policies. XFPM‐RBAC builds upon the FPM‐RBAC security policy model that we have recently proposed. XFPM‐RBAC consists of XML schemas, which define domain security policy, interdomain security policy, locations, mobility, and SOD constructs. A Security Policy Management Interface application is also developed for specification and administration of security policies as a prototype implementation of XFPM‐RBAC. XFPM‐RBAC supports extraction of formal specifications from security policies for the purpose of automated verification of security policies. Automated extraction of formal specifications is based on XSLT (Extensible Stylesheet Language Transformations). Formal specification of security policies together with location and mobility constraints within security policy rules are based on ambient calculus and ambient logic. Copyright © 2012 John Wiley & Sons, Ltd.
Improvement on the fault‐tolerant group key agreement protocol of Zhao et al.
Authors: Wang Zhiwei 
Published: January 2012

AbstractIn 2010, Zhao et al. proposed a fault‐tolerant group key agreement protocol based on RSA cryptosystem. In their protocol, malicious participants can be detected in the fault detection phase. Thus, they do not disrupt the key agreement process. However, there exists a drawback in the protocol of Zhao et al. After two rounds of trying, an adversary can impersonate any other group member in the third round. We propose an improved protocol to overcome this drawback. The efficiency and security analysis of our improved protocol are also provided in detail. Copyright © 2012 John Wiley & Sons, Ltd.
Revisiting network scanning detection using sequential hypothesis testing
Authors: Alsaleh Mansour , van Oorschot Paul C. 
Published: January 2012

ABSTRACTNetwork scanning is a common, effective technique to search for vulnerable Internet hosts and to explore the topology and trust relationships between hosts in a target network. Given that the purpose of scanning is to search for responsive hosts and network services, behavior‐based scanning detection techniques based on the state of inbound connection attempts remain effective against evasion. Many of today's network environments, however, feature a dynamic and transient nature with several network hosts and services added or stopped (either permanently or temporarily) over time. In this paper, working with recent network traces from two different environments, we re‐examine the Threshold Random Walk (TRW) scan detection algorithm, and we show that the number of false positives is proportional to the transiency of the offered services. To address the limitations found, we present a modified algorithm (Stateful Threshold Random Walk (STRW) algorithm) that utilizes active mapping of network services to take into account benign causes of failed connection attempts. The STRW algorithm eliminates a significant portion of TRW false positives (e.g., 29% and 77% in two datasets studied). Copyright © 2012 John Wiley & Sons, Ltd.
Performance enhancement of TinyECC based on multiplication optimizations
Authors: Seo Hwajeong , Shim Kyung‐Ah , Kim Howon 
Published: January 2012

ABSTRACTBecause wireless sensor network (WSN), which is composed of a large number of low‐cost and resource‐constrained devices, communicates on the basis of wireless protocols such as IEEE 802.15.4, ZigBee, and DASH‐7, it is easily vulnerable to eavesdropping, illegal modification, privacy infringement and denial‐of‐service attacks. These attacks destroy the data integrity, confidentiality, and authentication of the basic WSN security requirements and then the reliability and security of the WSN‐based applications are deteriorated. There have been many research efforts to make secure WSN environments. Among these efforts, TinyECC is one of outstanding works. It provides several security protocols such as Elliptic Curve Diffie–Hellman, Elliptic Curve Digital Signature Algorithm, and Elliptic Curve Integrated Encryption Scheme, based on the Elliptic Curve Cryptography (ECC). TinyECC is basically a well‐written TinyOS‐based code and is optimized to resource‐constrained environments. The Barrett reduction, hybrid multiplication, and several optimization techniques are also used for high performance even with low‐energy consumption. However, the hybrid multiplication technique used in TinyECC is known to be not suitable for 16‐bit processor, MSP430, which is a familiar processor for sensor node. This is due to the fact that the MSP 430 processor does not provide enough number of registers for hybrid multiplication techniques. Because the multiplication operation over the finite field is a major operation of the ECC, it causes a high latency of multiplication operations and eventually degrades the performance of the ECC operation. In this paper, we propose a novel multiplication operation based on the cached operands and reordered partial products. The proposed method shows that the latency of the polynomial multiplication, which is the core operation of the ECC, is 6% smaller than previously known results. Copyright © 2012 John Wiley & Sons, Ltd.
Environmental capabilities and corporate strategy: exploring acquisitions among US manufacturing firms
Authors: Berchicci Luca , Dowell Glen , King Andrew A. 
Published: January 2012

AbstractIn this article, we investigate whether environmental capabilities influence firms' corporate strategies, a topic that has received little attention to date. We hypothesize that firms are more likely to acquire facilities when ownership facilitates the transfer of capabilities either to or from the facility. Using a panel from the U.S. government's Toxics Release Inventory Program, we find firms with superior environmental capabilities are significantly more likely to acquire physically proximate facilities with inferior environmental capabilities and vice versa. Our results extend theories of both corporate and environmental strategy. Copyright © 2012 John Wiley & Sons, Ltd.
Understanding Dissipative Tip–Molecule Interactions with Submolecular Resolution on an Organic Adsorbate
Authors: Langewisch Gernot , Kamiński Wojciech , Braun Daniel‐Alexander , Möller Rolf , Fuchs Harald , Schirmeisen André , Pérez Rubén 
Published: January 2012

AbstractThree‐dimensional force spectroscopy measurements on 3,4,9,10‐perylene‐tetra‐carboxylic dianhydride adsorbed on Ag(111) are combined with first‐principles calculations to characterize the dissipative tip–molecule interactions with submolecular resolution. The experiments reveal systematic differences between the energy dissipation at the end groups and the center of the molecules that change with the tip–sample distance. Guided by the strength of the experimental conservative forces, an Ag‐contaminated Si tip is identified as the likely tip termination in the experiments. Based on this tip configuration, the energy dissipation in the tip–sample contact is determined from the approach and retraction force curves calculated as a function of distance for different molecule sites. These calculations provide an explanation for the experimental trends in terms of the competition between localized dissipation mechanisms involving the quite mobile oxygen atoms on the sides of the molecule, and global molecular deformations involving the more rigid perylene core. The results confirm that the observed dissipation can be explained in terms of adhesion hysteresis and show the power of combined experimental–theoretical spectroscopy studies in the characterization of the underlying microscopic mechanisms.