bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative comparison of delayed ferumoxytol T1 enhancement with immediate gadoteridol enhancement in high grade gliomas
Authors: Horváth Andrea , Varallyay Csanad G. , Schwartz Daniel , Toth Gerda B. , Netto Joao P. , Barajas Ramon , Várallyay Péter , Szidonya László , Firkins Jenny , Youngers Emily , Fu Rongwei , Ambady Prakash , Bogner Péter , Neuwelt Edward A. 
Published: December 2017

PurposeDelayed ferumoxytol enhancement on T1‐weighted images appears visually similar to gadoteridol enhancement. The purpose of this study was to quantitatively compare ferumoxytol T1 enhancement to gadoteridol enhancement with an objective, semi‐automated method.Methods206 sets of post‐gadoteridol and 24 h post‐ferumoxytol T1‐weighted scans from 58 high grade glioma patients were analyzed (9 pre‐chemoradiation, 111 < 90 days post‐chemoradiation, 21 > 90 days post‐chemoradiation, 65 post‐bevacizumab scans). Enhancement volumes and signal intensities normalized to normal appearing tissue proximal to enhancement were calculated with a semi‐automated method. Enhancement cube root volumes (D) and signal intensities (SI) were compared between the 2 contrast agents, and relative difference of D and SI were compared in different treatment groups with multivariate analysis. Within patient differences in D and SI before and after treatment with bevacizumab or steroid were assessed in 26 patients in each treatment group.ResultsWhen compared to gadoteridol, ferumoxytol D was 13.83% smaller and SI was 7.24% lower (P < 0.0001). The relative differences in D and SI between the 2 contrast agents were not significantly different between treatment groups (P > 0.05). Relative difference in D and SI did not change significantly in response to bevacizumab (P = 0.5234 and P = 0.2442, respectively) or to steroid (P = 0.3774, P = 0.0741) in the within patient comparison.ConclusionThe correlation between the 2 contrast agents’ enhancement size and signal intensity and their similar behavior in response to therapy suggest that ferumoxytol can be used for revealing enhancement in high grade glioma patients. Magn Reson Med 80:224–230, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
A z‐gradient array for simultaneous multi‐slice excitation with a single‐band RF pulse
Authors: Ertan Koray , Taraghinia Soheil , Sadeghi Alireza , Atalar Ergin 
Published: December 2017

PurposeMulti‐slice radiofrequency (RF) pulses have higher specific absorption rates, more peak RF power, and longer pulse durations than single‐slice RF pulses. Gradient field design techniques using a z‐gradient array are investigated for exciting multiple slices with a single‐band RF pulse.Theory and MethodsTwo different field design methods are formulated to solve for the required current values of the gradient array elements for the given slice locations. The method requirements are specified, optimization problems are formulated for the minimum current norm and an analytical solution is provided. A 9‐channel z‐gradient coil array driven by independent, custom‐designed gradient amplifiers is used to validate the theory.ResultsPerformance measures such as normalized slice thickness error, gradient strength per unit norm current, power dissipation, and maximum amplitude of the magnetic field are provided for various slice locations and numbers of slices. Two and 3 slices are excited by a single‐band RF pulse in simulations and phantom experiments.ConclusionThe possibility of multi‐slice excitation with a single‐band RF pulse using a z‐gradient array is validated in simulations and phantom experiments. Magn Reson Med 80:400–412, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
HeS‐CoP: Heuristic switch‐controller placement scheme for distributed SDN controllers in data center networks
Authors: Kim Woojoong , Li Jian , Hong James Won‐Ki , Suh Young‐Joo 
Published: December 2017

SummarySoftware‐defined networking (SDN) has been widely researched and used to manage large‐scale networks such as data center networks (DCNs). An early stage of SDN controller experienced low responsiveness, low scalability, and low reliability. To solve these problems, distributed SDN controllers have been proposed. The concept of distributed SDN controllers distributes control messages among multiple SDN controllers. However, distributed SDN controllers must assign a master controller for each networking devices. Most previous studies, however, did not consider the characteristics of DCNs. Thus, they are not suitable to operate in DCNs. In this paper, we propose HeS‐CoP, a heuristic switch‐controller placement scheme for distributed SDN controllers in DCNs. With the control traffic load and CPU load, HeS‐CoP decides when our scheme should be performed in DCNs. To show the feasibility of HeS‐CoP, we designed and implemented an orchestrator that contains our proposed scheme and then evaluated our proposed scheme. As a result, our proposed scheme well distributes the control traffic load, decreases the average CPU load, and reduces the packet delay.
Computational certification under limited experiments
Authors: Fish Jacob , Yuan Zifeng , Kumar Rajesh 
Published: December 2017

SummaryA computational certification framework under limited experimental data is developed. By this approach, a high‐fidelity model (HFM) is first calibrated to limited experimental data. Subsequently, the HFM is employed to train a low‐fidelity model (LFM). Finally, the calibrated LFM is utilized for component analysis. The rational for utilizing HFM in the initial stage stems from the fact that constitutive laws of individual microphases in HFM are rather simple so that the number of material parameters that needs to be identified is less than in the LFM. The added complexity of material models in LFM is necessary to compensate for simplified kinematical assumptions made in LFM and for smearing discrete defect structure. The first‐order computational homogenization model, which resolves microstructural details including the structure of defects, is selected as the HFM, whereas the reduced‐order homogenization is selected as the LFM. Certification framework illustration, verification, and validation are conducted for ceramic matrix composite material system comprised of the 8‐harness weave architecture. Blind validation is performed against experimental data to validate the proposed computational certification framework.
A Fourier transformation‐based method for gradient‐enhanced modeling of fatigue
Authors: Kindrachuk Vitaliy M. , Titscher Thomas , Unger Jörg F. 
Published: December 2017

SummaryA key limitation of the most constitutive models that reproduce a degradation of quasi‐brittle materials is that they generally do not address issues related to fatigue. One reason is the huge computational costs to resolve each load cycle on the structural level. The goal of this paper is the development of a temporal integration scheme, which significantly increases the computational efficiency of the finite element method in comparison to conventional temporal integrations. The essential constituent of the fatigue model is an implicit gradient‐enhanced formulation of the damage rate. The evolution of the field variables is computed as a multiscale Fourier series in time. On a microchronological scale attributed to single cycles, the initial boundary value problem is approximated by linear BVPs with respect to the Fourier coefficients. Using the adaptive cycle jump concept, the obtained damage rates are transferred to a coarser macrochronological scale associated with the duration of material deterioration. The performance of the developed method is hence improved due to an efficient numerical treatment of the microchronological problem in combination with the cycle jump technique on the macrochronological scale. Validation examples demonstrate the convergence of the obtained solutions to the reference simulations while significantly reducing the computational costs.
Time finite element based Moreau‐type integrators
Authors: Capobianco G. , Eugster S. R. 
Published: December 2017

SummaryWith the postulation of the principle of virtual action, we propose, in this paper, a variational framework for describing the dynamics of finite dimensional mechanical systems, which contain frictional contact interactions. Together with the contact and impact laws formulated as normal cone inclusions, the principle of virtual action directly leads to the measure differential inclusions commonly used in the dynamics of nonsmooth mechanical systems. The discretization of the principle of virtual action in its strong and weak variational form by local finite elements in time provides a structured way to derive various time‐stepping schemes. The constitutive laws for the impulsive and nonimpulsive contact forces, ie, the contact and impact laws, are treated on velocity‐level by using a discrete contact law for the percussion increments in the sense of Moreau. Using linear shape functions and different quadrature rules, we obtain three different stepping schemes. Besides the well‐established Moreau time‐stepping scheme, we can present two alternative integrators referred to as symmetric and variational Moreau‐type stepping schemes. A suitable benchmark example shows the superiority of the newly proposed integrators in terms of energy conservation properties, accuracy, and convergence.
A mortar finite element approach for point, line, and surface contact
Authors: Farah P. , Wall W. A. , Popp A. 
Published: December 2017

SummaryAn approach for investigating finite deformation contact problems with frictional effects with a special emphasis on nonsmooth geometries such as sharp corners and edges is proposed in this contribution. The contact conditions are separately enforced for point contact, line contact, and surface contact by employing 3 different sets of Lagrange multipliers and, as far as possible, a variationally consistent discretization approach based on mortar finite element methods. The discrete unknowns due to the Lagrange multiplier approach are eliminated from the system of equations by employing so‐called dual or biorthogonal shape functions. For the combined algorithm, no transition parameters are required, and the decision between point contact, line contact, and surface contact is implicitly made by the variationally consistent framework. The algorithm is supported by a penalty regularization for the special scenario of nonparallel edge‐to‐edge contact. The robustness and applicability of the proposed algorithms are demonstrated with several numerical examples.
Political will and government anti‐corruption efforts: What does the evidence say?
Authors: Ankamah Samuel Siebie , Manzoor E Khoda S M 
Published: December 2017

Summary“Political will” is oft‐cited as the major obstacle to government's anti‐corruption efforts. Notwithstanding, there is remarkably little systematic analysis of the concept, with some scholars describing it as the “slipperiest concept in the policy lexicon,” whereas others are calling for its empirical relevance. This paper tries to unpack the “black box” of political will by making it an empirically relevant concept drawing on evidence from two Asian countries; Singapore and Bangladesh. Four key indicators based on the works of earlier scholars are used including origin of the initiative; comprehension and extent of analysis; credible sanctions; and resource dedication and sustenance are used. The paper also uses Transparency International's Corruption Perception Index, World Bank's World Governance Indicators (Control of Corruption and Government Effectiveness), and Political, Economic and Risk Consultancy's annual survey in Asia, as outcome measures. Based on the empirical evidence from the two countries, the paper shows that political will indeed has a positive influence on government's anti‐corruption efforts. Although political will may not be sufficient, it is a necessary condition to fight corruption, and that the difference between the positions of Singapore and Bangladesh on various global corruption league tables may be attributed to political will.
Anti‐oncostatin M antibody inhibits the pro‐malignant effects of oncostatin M receptor overexpression in squamous cell carcinoma
Authors: Kucia‐Tran Justyna A , Tulkki Valtteri , Scarpini Cinzia G , Smith Stephen , Wallberg Maja , Paez‐Ribes Marta , Araujo Angela M , Botthoff Jan , Feeney Maria , Hughes Katherine , Caffarel Maria M , Coleman Nicholas 
Published: December 2017

AbstractThe oncostatin M (OSM) receptor (OSMR) shows frequent gene copy number gains and overexpression in cervical squamous cell carcinomas (SCCs), associated with adverse clinical outcomes. In SCC cells that overexpress OSMR, the major ligand OSM induces multiple pro‐malignant effects, including invasion, secretion of angiogenic factors, and metastasis. Here, we demonstrate, for the first time, that OSMR overexpression in SCC cells activates cell‐autonomous feed‐forward signalling, via further expression of OSMR and OSM and sustained STAT3 activation, despite expression of the negative regulator suppressor of cytokine signalling 3 (SOCS3). The pro‐malignant effects associated with OSMR overexpression are critically mediated by JAK–STAT3 activation, which is induced by exogenous OSM and also by autocrine OSM–OSMR interactions. Importantly, specific inhibition of OSM–OSMR interactions by neutralizing antibodies significantly inhibits STAT3 activation and feed‐forward signalling, leading to reduced invasion, angiogenesis, and metastasis. Our findings are supported by data from 1254 clinical SCC samples, in which OSMR levels correlated with multiple cognate genes, including OSM, STAT3, and downstream targets. These data strongly support the development of OSM–OSMR‐blocking antibodies as biologically targeted therapies against SCCs of the cervix and other anatomical sites. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Donor‐derived, metastatic urothelial cancer after kidney transplantation associated with a potentially oncogenic BK polyomavirus
Authors: Müller David C , Rämö Maarit , Naegele Klaudia , Ribi Sebastian , Wetterauer Christian , Perrina Valeria , Quagliata Luca , Vlajnic Tatjana , Ruiz Christian , Balitzki Beate , Grobholz Rainer , Gosert Rainer , Ajuh Elvis T , Hirsch Hans H , Bubendorf Lukas , Rentsch Cyrill A 
Published: December 2017

AbstractBK polyomavirus has been linked to urothelial carcinoma in immunosuppressed patients. Here, we performed comprehensive genomic analysis of a BK polyomavirus‐associated, metachronous, multifocal and metastatic micropapillary urothelial cancer in a kidney transplant recipient. Dissecting cancer heterogeneity by sorting technologies prior to array‐comparative genomic hybridization followed by short tandem repeat analysis revealed that the metastatic urothelial cancer was of donor origin (4‐year‐old male). The top 50 cancer‐associated genes showed no key driver mutations as assessed by next‐generation sequencing. Whole genome sequencing and BK polyomavirus‐specific amplification provided evidence for episomal and subgenomic chromosomally integrated BK polyomavirus genomes, which carried the same unique 17‐bp deletion signature in the viral non‐coding control region (NCCR). Whereas no role in oncogenesis could be attributed to the host gene integration in chromosome 1, the 17‐bp deletion in the NCCR increased early viral gene expression, but decreased viral replication capacity. Consequently, urothelial cells were exposed to high levels of the transforming BK polyomavirus early proteins large tumour antigen and small tumour antigen from episomal and integrated gene expression. Surgery combined with discontinuation of immunosuppression resulted in complete remission, but sacrificed the renal transplant. Thus, this report links, for the first time, BK polyomavirus NCCR rearrangements with oncogenic transformation in urothelial cancer in immunosuppressed patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Cyclic AMP‐dependent protein kinase catalytic subunit A (PRKACA): the expected, the unexpected, and what might be next
Authors: Stratakis Constantine A 
Published: December 2017

AbstractProtein kinase A (PKA) or cyclic‐AMP (cAMP)‐dependent kinase was among the first serine–threonine kinases to be molecularly and functionally characterized. For years, it was investigated as the enzyme that mediates cAMP functions in almost all cell systems and organisms studied to date. Despite PKA's critical role in signaling and the long history of investigations of cAMP in oncogenesis (dating back to the 1970s), it was not until relatively recently that PKA defects were found to be directly involved in tumor predisposition. First, PKA's main regulatory subunit, PRKAR1A, was found to be mutated in Carney complex, a genetic syndrome that predisposes to heart tumors (cardiac myxomas) and a variety of other lesions of the endocrine system, including the adrenal cortex, and several cancers, including liver carcinoma. Then, PKA's main catalytic subunit, PRKACA, was found to be mutated in sporadic adrenal tumors and fibrolamellar liver carcinoma. Not surprisingly, therefore, a new research study published in The Journal of Pathology showed PRKACA mutations in sporadic cardiac myxomas. The real question is what other pathologies will be found to be due to PRKACA (or other PKA subunit) defects. The possibilities abound and may show the way for a totally new class of medications that target cAMP signaling to be useful in fighting the corresponding tumors. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Atomistic insights on the LCST behavior of PMEO2MA in water by molecular dynamics simulations
Authors: Dalgakiran Eray , Tatlipinar Hasan 
Published: December 2017

ABSTRACTFully atomistic molecular dynamics simulations of poly(2‐[2‐methoxyethoxy]ethyl methacrylate) (PMEO2MA) in water at temperatures below and above its lower critical solution temperature (LCST) were performed to improve the understanding of its LCST behavior. Atomic trajectories were used to calculate various structural and dynamic properties. Simulation results show that PMEO2MA undergo a distinct coil‐to‐globule transition above LCST. Detailed analyses of the number of first hydration shell water molecules around various atomic regions are revealed that the water solubility of PMEO2MA below LCST is mainly provided by the hydrophobic hydration around the side chain carbon atoms. This is achieved by the cage‐like water network formations which are disrupted when the temperature is increased above LCST, accompanied by significant amount of water molecule release and local water‐ordering reduction, which leads to the LCST phase transition. Furthermore, other analyses such as the number of hydrogen bonds and hydrogen bond lifetimes suggest that intermolecular hydrogen bondings between polymer and water molecules have little effect on the phase transition. Our results will contribute to a better understanding on the LCST phase transition of oligo(ethylene glycol) methyl ether methacrylate (OEGMA)‐based homopolymers at atomistic level that will be useful when designing homo‐ and co‐polymers of OEGMAs with desired properties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 429–441
Validation of simulated temperature profiles at rock walls in the eastern alps (Dachstein)
Authors: Schnepfleitner H. , Rode M. , Sass O. 
Published: December 2017

AbstractWhile rock temperature is a key factor for many geomorphic phenomena in high mountains, assessing the small‐scale temperature distribution remains challenging. We adapted the program package WUFI®, originally designed to calculate energy and moisture fluxes in building walls, for modeling natural rock faces. We determined physical rock properties and local meteorological parameters as input data for the simulations at rock walls in the Dachstein Mountains, Austria, and calculated annual temperature fluctuations at the surface and at 3, 10, 30, 50 and 100 cm depth, including different elevations, aspects and slope angles. Thirty‐seven temperature sensors inserted into drillholes of different depths at ten locations (altitudes from 2300 to 2700 m) were used to validate the simulation. Additionally, surface temperatures were determined from infrared images; these were calibrated for surface emissivity using further temperature sensors. Simulated temperatures and sensor data show very good agreement, with a mean correlation coefficient of 0.94, and the validation of surface temperatures by thermal imaging also delivered good results (r > 0.9). This means that the WUFI software can be used to model complex temperature distributions in natural rock wall settings, thus making it a valuable tool for geomorphological investigations.
Exploring the effects of sparse restraints on protein structure prediction
Authors: Mandalaparthy Varun , Sanaboyana Venkata Ramana , Rafalia Hitesh , Gosavi Shachi 
Published: December 2017

AbstractOne of the main barriers to accurate computational protein structure prediction is searching the vast space of protein conformations. Distance restraints or inter‐residue contacts have been used to reduce this search space, easing the discovery of the correct folded state. It has been suggested that about 1 contact for every 12 residues may be sufficient to predict structure at fold level accuracy. Here, we use coarse‐grained structure‐based models in conjunction with molecular dynamics simulations to examine this empirical prediction. We generate sparse contact maps for 15 proteins of varying sequence lengths and topologies and find that given perfect secondary‐structural information, a small fraction of the native contact map (5%‐10%) suffices to fold proteins to their correct native states. We also find that different sparse maps are not equivalent and we make several observations about the type of maps that are successful at such structure prediction. Long range contacts are found to encode more information than shorter range ones, especially for α and αβ‐proteins. However, this distinction reduces for β‐proteins. Choosing contacts that are a consensus from successful maps gives predictive sparse maps as does choosing contacts that are well spread out over the protein structure. Additionally, the folding of proteins can also be used to choose predictive sparse maps. Overall, we conclude that structure‐based models can be used to understand the efficacy of structure‐prediction restraints and could, in future, be tuned to include specific force‐field interactions, secondary structure errors and noise in the sparse maps.
Cucurbitacin B acts a potential insect growth regulator by antagonizing 20‐hydroxyecdysone activity
Authors: Zou Chuanshan , Liu Guifen , Liu Suning , Liu Shumin , Song Qisheng , Wang Jian , Feng Qili , Su Yunlin , Li Sheng 
Published: December 2017

AbstractBACKGROUND20‐Hydroxyecdysone (20E), a crucial insect steroid hormone, can bind to its cognate nuclear receptor composed of ecdysone receptor (EcR) and ultraspiracle (USP) to activate expression of 20E‐response genes, enabling subsequent metamorphosis. In this study, we tried to find out which steroid‐like compounds can block insect metamorphosis effectively and provide useful information for biopesticide study. For this purpose, we screened 126 steroid‐like compounds for possible 20E antagonists using a dual‐luciferase reporter assay with Drosophila melanogaster Kc and Bombyx mori Bm12 cells.RESULTSAmong 126 steroid‐like compounds, three cucurbitacins (CucB, D and E) were identified as 20E antagonists in both Kc and Bm12 cells. Notably, CucB caused significant molting defects and mortality in both B. mori and D. melanogaster larvae, and dramatically hindered larval growth of Helicoverpa armigera by its anti‐feeding activity.CONCLUSIONIn vivo and in vitro experiments demonstrate that CucB acts as a potential insect growth regulator by antagonizing 20E activity and thus blocking molting and metamorphosis induced by 20E signaling. © 2017 Society of Chemical Industry