bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesoscale Simulations of the Rheology of Filled Styrene–Butadiene Compounds
Authors: Fitzgerald Barry W. , den Otter Wouter K. , Luding Stefan , Briels Wim J. 
Published: May 2018

AbstractThe ability of a highly coarse‐grained polymer model is explored to simulate the impact of carbon black (CB) filler concentration on the rheological properties of unvulcanized styrene–butadiene melts—an intermediate stage in the production of styrene–butadiene rubber (SBR) commonly used in tyres. Responsive particle dynamics (RaPiD), previously used to study dilute polymeric systems, models entire polymers as single particles interacting through a combination of conservative interactions and transient entanglement‐mimicking forces. The simulation parameters are tuned to the linear rheology of the unfilled melt, as measured using a rubber process analyzer (RPA). For the filled compounds, only the interaction between the polymers and fillers is varied. On top of excluded volume interactions, a slight attraction (≈0.1kBT) between polymers and fillers is required to attain agreement with RPA measurements. The physical origins of the small strength of this interaction are discussed. This method offers potential for future numerical investigations of filled melts.
pH and Heat Resistance of the Major Celery Allergen Api g 1
Authors: Rib‐Schmidt Carina , Riedl Philipp , Meisinger Veronika , Schwaben Luisa , Schulenborg Thomas , Reuter Andreas , Schiller Dirk , Seutter von Loetzen Christian , Rösch Paul 
Published: May 2018

ScopeThe major celery allergen Api g 1 is a member of the pathogenesis‐related 10 class protein family. This study aims to investigate the impact of heat and pH on the native protein conformation required for Immunoglobulin E (IgE) recognition.Methods and resultsSpectroscopic methods, MS and IgE‐binding analyses are used to study the effects of pH and thermal treatment on Api g 1.0101. Heat processing results in a loss of the native protein fold via denaturation, oligomerization, and precipitation along with a subsequent reduction of IgE recognition. The induced effects and timescales are strongly pH dependent. While Api g 1 refolds partially into an IgE‐binding conformation at physiological pH, acidic pH treatment leads to the formation of structurally heat‐resistant, IgE‐reactive oligomers. Thermal processing in the presence of a celery matrix or at pH conditions close to the isoelectric point (pI = 4.63) of Api g 1.0101 results in almost instant precipitation.ConclusionThis study demonstrates that Api g 1.0101 is not intrinsically susceptible to heat treatment in vitro. However, the pH and the celery matrix strongly influence the stability of Api g 1.0101 and might be the main reasons for the observed temperature lability of this important food allergen.
Polarized x‐ray excitation for scatter reduction in x‐ray fluorescence computed tomography
Authors: Vernekohl Don , Tzoumas Stratis , Zhao Wei , Xing Lei 
Published: May 2018

PurposeX‐ray fluorescence computer tomography (XFCT) is a new molecular imaging modality which uses x‐ray excitation to stimulate the emission of fluorescent photons in high atomic number contrast agents. Scatter contamination is one of the main challenges in XFCT imaging which limits the molecular sensitivity. When polarized x rays are used, it is possible to reduce the scatter contamination significantly by placing detectors perpendicular to the polarization direction. This study quantifies scatter contamination for polarized and unpolarized x‐ray excitation and determines the advantages of scatter reduction.MethodsThe amount of scatter in preclinical XFCT is quantified in Monte Carlo simulations. The fluorescent x rays are emitted isotropically, while scattered x rays propagate in polarization direction. The magnitude of scatter contamination is studied in XFCT simulations of a mouse phantom. In this study, the contrast agent gold is examined as an example, but a scatter reduction from polarized excitation is also expected for other elements. The scatter reduction capability is examined for different polarization intensities with a monoenergetic x‐ray excitation energy of 82 keV. The study evaluates two different geometrical shapes of CZT detectors which are modeled with an energy resolution of 1 keV FWHM at an x‐ray energy of 80 keV. Benefits of a detector placement perpendicular to the polarization direction are shown in iterative and analytic image reconstruction including scatter correction. The contrast to noise ratio (CNR) and the normalized mean square error (NMSE) are analyzed and compared for the reconstructed images.ResultsA substantial scatter reduction for common detector sizes was achieved for 100% and 80% linear polarization while lower polarization intensities provide a decreased scatter reduction. By placing the detector perpendicular to the polarization direction, a scatter reduction by factor up to 5.5 can be achieved for common detector sizes. The image reconstruction showed that for a scatter magnitude decrease by a factor of 2.4, the molecular sensitivity could almost be doubled.ConclusionScatter reduction lowers the amount of noise in the projection datasets and reconstructed images which enhance molecular sensitivity at equal dose. The results support the use of linear polarized x rays to reduce scatter in XFCT imaging.
Technical Note: Harmonic analysis applied to MR image distortion fields specific to arbitrarily shaped volumes
Authors: Stanescu T. , Jaffray D. 
Published: May 2018

PurposeMagnetic resonance imaging is expected to play a more important role in radiation therapy given the recent developments in MR‐guided technologies. MR images need to consistently show high spatial accuracy to facilitate RT‐specific tasks such as treatment planning and in‐room guidance. The present study investigates a new harmonic analysis method for the characterization of complex three‐dimensional (3D) fields derived from MR images affected by system‐related distortions.MethodsAn interior Dirichlet problem based on solving the Laplace equation with boundary conditions (BCs) was formulated for the case of a 3D distortion field. The second‐order boundary value problem (BVP) was solved using a finite elements method (FEM) for several quadratic geometries — that is, sphere, cylinder, cuboid, D‐shaped, and ellipsoid. To stress‐test the method and generalize it, the BVP was also solved for more complex surfaces such as a Reuleaux 9‐gon and the MR imaging volume of a scanner featuring a high degree of surface irregularities. The BCs were formatted from reference experimental data collected with a linearity phantom featuring a volumetric grid structure. The method was validated by comparing the harmonic analysis results with the corresponding experimental reference fields.ResultsThe harmonic fields were found to be in good agreement with the baseline experimental data for all geometries investigated. In the case of quadratic domains, the percentage of sampling points with residual values larger than 1 mm was 0.5% and 0.2% for the axial components and vector magnitude, respectively. For the general case of a domain defined by the available MR imaging field of view, the reference data showed a peak distortion of about 1 mm and 79% of the sampling points carried a distortion magnitude larger than 1 mm (tolerance intrinsic to the experimental data). The upper limits of the residual values after comparison with the harmonic fields showed max and mean of 1.4 and 0.25 mm, respectively, with only 1.5% of sampling points exceeding 1 mm.ConclusionsA novel harmonic analysis approach relying on finite element methods was introduced and validated for multiple volumes with surface shape functions ranging from simple to highly complex. Since a boundary value problem is solved the method requires input data from only the surface of the desired domain of interest. It is believed that the harmonic method will facilitate (a) the design of new phantoms dedicated for the quantitation of MR image distortions in large volumes and (b) an integrative approach of combining multiple imaging tests specific to radiotherapy into a single test object for routine imaging quality control.
A velocity field level set method for shape and topology optimization
Authors: Wang Yaguang , Kang Zhan 
Published: May 2018

SummaryIn this paper, we propose a new implementation of the level set shape and topology optimization, the velocity field level set method. Therein, the normal velocity field is constructed with specified basis functions and velocity design variables defined on a given set of points that are independent of the finite element mesh. A general mathematical programming algorithm can be employed to find the optimal normal velocities on the basis of the sensitivity analysis. As compared with conventional level set methods, mapping the variational boundary shape optimization problem into a finite‐dimensional design space and the use of a general optimizer makes it more efficient and straightforward to handle multiple constraints and additional design variables. Moreover, the level set function is updated by the Hamilton‐Jacobi equation using the normal velocity field; thus, the inherent merits of the implicit representation is retained. Therefore, this method combines the merits of both the general mathematical programming and conventional level set methods. Integrated topology optimization of structures with embedded components of designable geometries is considered to show the capability of this method to deal with general design variables. Several numerical examples in 2D or 3D design domains illustrate the robustness and efficiency of the method using different basis functions.
Equipotent enantiomers of cyclic opioid peptides at μ opioid receptor
Authors: Weltrowska Grazyna , Nguyen Thi M.‐D. , Chung Nga N. , Wilkes Brian C. , Schiller Peter W. 
Published: May 2018

AbstractHead‐to‐tail cyclized analogs of the µ opioid receptor (MOR) agonist tetrapeptides DALDA (H‐Tyr‐D‐Arg‐Phe‐Lys‐NH2 and [Dmt1]DALDA (H‐Dmt‐D‐Arg‐Phe‐Lys‐NH2; Dmt = 2′,6′‐dimethyltyrosine) and their enantiomers (mirror‐image isomers) were synthesized and pharmacologically characterized in vitro. Three pairs of enantiomeric cyclic peptides with both mirror‐image isomers having equipotent MOR binding affinities but different binding affinities at the δ and κ opioid receptors were identified. The cyclic peptide enantiomers c[‐D‐Arg‐Phe‐Lys‐Tyr‐] (1) and c[‐Arg‐D‐Phe‐D‐Lys‐D‐Tyr‐] (2) showed nearly identical MOR binding affinity (1‐2 nM) and equipotent MOR antagonist activity. The results of a MOR docking study indicated a very similar binding mode of the two enantiomers with nearly complete spatial overlap of the peptide ring structures and side chain interactions with the same MOR residues. Compounds 1 and 2 represent the first pair of enantiomeric G‐protein‐coupled receptor (GPCR) ligands having multiple chiral centers, with both optical antipodes showing equal, low nanomolar receptor binding affinity.
Clinical Outcomes with Penicillin Versus Alternative β‐Lactams in the Treatment of Penicillin‐Susceptible Staphylococcus aureus Bacteremia
Authors: Shah Megan D. , Wardlow Lynn C. , Stevenson Kurt B. , Coe Kelci E. , Reed Erica E. 
Published: May 2018

ObjectivesTo identify the impact of penicillin versus alternative β‐lactams on clinical outcomes in patients with penicillin‐susceptible Staphylococcus aureus (PSSA) bacteremia.DesignRetrospective cohort study.SettingAcademic medical center.PatientsAdult patients with PSSA bacteremia treated with a β‐lactam as definitive therapy.MeasurementsThe primary outcome was a composite end point of 30‐day clinical failure (change in PSSA therapy due to persistent or worsening signs and symptoms, PSSA bacteremia recurrence or persistence, and/or infection‐related mortality) in patients treated with penicillin versus alternative β‐lactams. Secondary outcomes included infection‐related and hospital length of stay (LOS), 90‐day recurrence, 90‐day infection‐related readmission, 30‐day all‐cause mortality, adverse drug events (ADEs), and 30‐day change in PSSA therapy due to ADEs. A subgroup analysis comparing penicillin, nafcillin, and cefazolin was also conducted.Main ResultsFor the 122 patients who were included, the most common definitive therapies were nafcillin (37%), cefazolin (29%), and penicillin (21%). No difference was found in 30‐day clinical failure (4% vs 11%, p=0.46), infection‐related LOS (12 days vs 11 days, p=0.39), hospital LOS (12.5 days vs 12 days, p=0.69), 90‐day recurrence (p=1.00), 90‐day infection‐related readmission (p=1.00), or 30‐day all‐cause mortality (p=0.45) between penicillin and other β‐lactams. The prevalence of ADEs was different among penicillin, nafcillin, and cefazolin (p=0.049), with nafcillin requiring more changes in therapy (p=0.005).ConclusionsDefinitive therapy with penicillin had similar efficacy compared with alternative β‐lactams for the treatment of PSSA bacteremia. However, nafcillin was associated with more ADEs requiring a change in therapy.
Implementation of an ICU‐Specific Alcohol Withdrawal Syndrome Management Protocol Reduces the Need for Mechanical Ventilation
Authors: Heavner Jason J. , Akgün Kathleen M. , Heavner Mojdeh S. , Eng Claire C. , Drew Matthew , Jackson Peter , Pritchard David , Honiden Shyoko 
Published: May 2018

Study ObjectiveAlcohol use disorders are prevalent and put patients at risk for developing alcohol withdrawal syndrome (AWS). Treatment of AWS with a symptom‐triggered protocol standardizes management and may avoid AWS‐related complications. The objective of this study was to evaluate whether implementation of a specific intensive care unit (ICU) symptom‐triggered protocol for the management of AWS was associated with improved clinical outcomes and, in particular, would reduce the risk of patients with AWS requiring mechanical ventilation.DesignRetrospective pre‐ and postprotocol implementation study.SettingA 36‐bed closed medical ICU (MICU) at a large tertiary care teaching hospital in an urban setting.PatientsA total of 233 adults admitted to the MICU with any diagnosis of alcohol use disorders based on International Classification of Diseases, Ninth Revision codes and who received at least one dose of any benzodiazepine; of these patients, 139 were in the preprotocol era (August 2009–January 2010 and August 2010–January 2011), and 94 were in the postprotocol era (August 2012–January 2013) after implementation of the Yale Alcohol Withdrawal Protocol (YAWP) in April 2012.Measurements and Main ResultsThe YAWP pairs a modified Minnesota Detoxification Scale with an order set that includes benzodiazepine dosing regimens and suggests adjuvant therapies. AWS was the primary reason for ICU admission (107/233 patients [45.9%]) and did not significantly vary between study eras (p=0.2). Of the 233 patients included, 81.1% were male and 67.0% were white, which did not significantly differ by study era. Severity of illness at MICU admission did not significantly differ between patients in the preprotocol and postprotocol eras (Acute Physiology and Chronic Health Evaluation [APACHE] II median scores of 12 [interquartile range (IQR) 9–17] and 12.5 [IQR 7–16], respectively, p=0.4). Median lorazepam‐equivalent dose per MICU day, duration of benzodiazepine infusion, and use of adjuvant therapy were not significantly different between eras. MICU intubation was less common in the postprotocol era (36/139 patients [25.9%] preprotocol vs 8/94 patients [8.5%] postprotocol, p=0.0009). ICU‐related pneumonia was also decreased in the postprotocol era (30/139 patients [21.6%] preprotocol vs 10/94 patients [10.6%] postprotocol, p=0.03). After adjusting for demographics, adjuvant therapies, and APACHE II scores, protocol implementation was associated with a decreased odds of MICU intubation (odds ratio 0.13, 95% confidence interval 0.04–0.39).ConclusionImplementation of YAWP was associated with a decreased risk of MICU intubation in patients at risk for AWS.
Dynamic mechanical and shape memory properties of copolymers based ono‐allylphenol type benzoxazines and diglycidyl ether of bisphenol‐A
Authors: Shen Shanshan , Li Cuiyun , Yang Huiyun , Zhang Yanyu , Han Fengan , Han Fuxin , Liu Yanfang 
Published: May 2018

AbstractThree benzoxazines based ono‐allylphenol and 1,6‐hexamethylenediamine (HDA) or 4,4′‐diaminodiphenyl methane (DDM) or 4,4′‐diaminodiphenyl ether (DDE) were respectively blended with diglycidyl ether of bisphenol‐A (DGEBA) in various weight ratios followed by thermal polymerization to prepare three series of benzoxazine/DGEBA copolymers. With increasing DGEBA content, the peak temperature of the exothermic peaks in the DSC curves shows a systematic increase for the three series of benzoxazine/DGEBA blends. Each copolymer shows a single glass transition temperature (Tg). As the content of DGEBA is increased,Tgreaches a minimum for the copolymer system based on HDA but a maximum for the two systems based on DDM and DDE. For the same benzoxazine/DGEBA weight ratio, copolymers based on DDM and DDE show highTgvalues over those based on HDA. The three series of benzoxazine/DGEBA copolymers exhibit a one‐way dual shape memory effect based onTg, and the shape memory properties of the copolymers under tensile deformation mode vary with the variation of both diamine bridge structure and DGEBA content. © 2018 Society of Chemical Industry
Functionalization of poly(bis‐thiophene methine)s via facile C–C bulk polymerization and their application as chemosensors for acid detection
Authors: Peng Kai , Pei Tong , Huang Ni , Yuan Liangjie , Liu Xinghai , Xia Jiangbin 
Published: May 2018

ABSTRACTUp to now, 3,4‐ethylenedioxythiophene (EDOT) or its modified analogs are indispensable units or subunits in all successful monomers for polythiophene synthesis through solid‐state polymerization (SSP). Here, a more open thiophene‐(CH(R))‐thiophene platform was developed successfully and corresponding poly(bis‐thiophene methine)s were obtained via C–C SSP or melt‐state polymerization (MSP), that is, bulk polymerization. Meanwhile, the observation of quite long effective Br–Br distance of 5.634 Å, which is more than 50% of halogen's double van der Waals radius (2rw), would help us to understand powerful capability of modulation of molecule movement and reaction under SSP. In addition, these polymers were further employed as acid sensors and they show highly sensitive response to HCl, MeSO3H, BF3‐OEt2, and HNO3. The detailed experiment reveals that P1 has the detection limit of 3.35 × 10−5 M for HCl. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1676–1683
Sampling plans for the zero‐inflated negative binomial distribution in the food industry
Authors: Wang Fu‐Kwun , Hailemariam Shalemu Sharew 
Published: May 2018

AbstractIn this paper, we propose 3 new sampling plans, including resubmitted single sampling plan (RSSP), repetitive group sampling (RGS) plan, and multiple dependent state (MDS) sampling plan to study the zero‐inflated negative binomial distribution in microbiological food safety and quality assurance practices. The unity value approach is used to find optimal plan parameters. The proposed plans are compared with the single sampling plan (SSP). We found that degree of clustering and excess of zeros counts affect the performance of all sampling plans. The MDS plan outperforms the SSP, RSSP, and RGS plans with respect to minimum average sample number in most cases. Both RGS and MDS plans show a comparable performance. The average run length is calculated to evaluate the rejection capability of the plans and signal the deterioration of the quality of lots. An example from 9 Irish abattoirs is used to illustrate the application of the proposed methods.
Higgs and Z assisted stop searches at hadron colliders
Authors: Su Shufang , Zhang Huanian 
Published: May 2018

Abstract

Current searches for the light top squark (stop) mostly focus on the decay channels of

$$ \tilde{t}\to t{\chi}_1^0 $$

t
˜

→
t

χ
1
0

or

$$ \tilde{t}\to b{\chi}_1^{\pm}\to bW{\chi}_1^0 $$

t
˜

→
b

χ
1
±

→
b
W

χ
1
0

, leading to "Image missing" final states for stop pair productions at the LHC. However, in supersymmetric scenarios with light neutralinos and charginos other than the neutralino lightest supersymmetric particle (LSP), more than one decay mode of the stop could be dominant. While those new decay modes could significantly weaken the current stop search limits at the LHC, they also offer alternative discovery channels for stop searches. In this paper, we studied the scenario with light Higgsino next-to-LSPs (NLSPs) and Bino LSP. The light stop decays primarily via

$$ {\tilde{t}}_1\to t{\chi}_2^0/{\chi}_3^0 $$

t
˜

1

→
t

χ
2
0

/

χ
3
0

, with the neutralinos subsequent decaying to a Z boson or a Higgs boson: χ
2
0
/χ
3
0
→ χ
1
0
h/Z. Pair production of light stops at the LHC leads to final states of "Image missing" or "Image missing" . We consider three signal regions: one charged lepton (1ℓ), two opposite sign charged leptons (2 OS ℓ) and at least three charged leptons (≥3ℓ). We found that the 1ℓ signal region of channel "Image missing" has the best reach sensitivity for light stop searches. For 14 TeV LHC with 300 fb−1 integrated luminosity, a stop mass up to 900 GeV can be discovered at 5σ significance, or up to 1050 GeV can be excluded at 95% C.L. Combining all three decay channels for 1ℓ signal region extends the reach for about 100−150 GeV. We also studied the stop reach at the 100 TeV pp collider with 3 ab−1 luminosity, with discovery and exclusion reach being 6 TeV and 7 TeV, respectively.
A new insight into the phase transition in the early Universe with two Higgs doublets
Authors: Bernon Jérémy , Bian Ligong , Jiang Yun 
Published: May 2018

Abstract

We study the electroweak phase transition in the alignment limit of the CP-conserving two-Higgs-doublet model (2HDM) of Type I and Type II. The effective potential is evaluated at one-loop, where the thermal potential includes Daisy corrections and is reliably approximated by means of a sum of Bessel functions. Both 1-stage and 2-stage electroweak phase transitions are shown to be possible, depending on the pattern of the vacuum development as the Universe cools down. For the 1-stage case focused on in this paper, we analyze the properties of phase transition and discover that the field value of the electroweak symmetry breaking vacuum at the critical temperature at which the first order phase transition occurs is largely correlated with the vacuum depth of the 1-loop potential at zero temperature.
We demonstrate that a strong first order electroweak phase transition (SFOEWPT) in the 2HDM is achievable and establish benchmark scenarios leading to different testable signatures at colliders. In addition, we verify that an enhanced triple Higgs coupling (including loop corrections) is a typical feature of the SFOPT driven by the additional doublet. As a result, SFOEWPT might be able to be probed at the LHC and future lepton colliders through Higgs pair production.
Unifying separation logic and region logic to allow interoperability
Authors: Bao Yuyan , Leavens Gary T. , Ernst Gidon 
Published: May 2018

AbstractFraming is important for specification and verification, especially in programs that mutate data structures with shared data, such as DAGs. Both separation logic and region logic are successful approaches to framing, with separation logic providing a concise way to reason about data structures that are disjoint, and region logic providing the ability to reason about framing for shared mutable data. In order to obtain the benefits of both logics for programs with shared mutable data, this paper unifies them into a single logic, which can encode both of them and allows them to interoperate. The new logic thus provides a way to reason about program modules specified in a mix of styles.