bluuebunny/crossref_metadata_2025_split huggingface dataset:
A mesh‐independent method for planar three‐dimensional crack growth in finite domains
Authors: Sheng A. , Ghoniem N. M. , Crosby T. , Po G. 
Published: August 2018

SummaryThe discrete crack mechanics (DCM) method is a dislocation‐based crack modeling technique where cracks are constructed using Volterra dislocation loops. The method allows for the natural introduction of displacement discontinuities, avoiding numerically expensive techniques. Mesh dependence in existing computational modeling of crack growth is eliminated by utilizing a superposition procedure. The elastic field of cracks in finite bodies is separated into two parts: the infinite‐medium solution of discrete dislocations and an finite element method solution of a correction problem that satisfies external boundary conditions. In the DCM, a crack is represented by a dislocation array with a fixed outer loop determining the crack tip position encompassing additional concentric loops free to expand or contract. Solving for the equilibrium positions of the inner loops gives the crack shape and stress field. The equation of motion governing the crack tip is developed for quasi‐static growth problems. Convergence and accuracy of the DCM method are verified with two‐ and three‐dimensional problems with well‐known solutions. Crack growth is simulated under load and displacement (rotation) control. In the latter case, a semicircular surface crack in a bent prismatic beam is shown to change shape as it propagates inward, stopping as the imposed rotation is accommodated.
A combined scheme of generalized finite difference method and Krylov deferred correction technique for highly accurate solution of transient heat conduction problems
Authors: Qu Wenzhen , Gu Yan , Zhang Yaoming , Fan Chia‐Ming , Zhang Chuanzeng 
Published: August 2018

SummaryThis paper presents a numerical framework for the highly accurate solutions of transient heat conduction problems. The numerical framework discretizes the temporal direction of the problems by introducing the Krylov deferred correction (KDC) approach, which is arbitrarily high order of accuracy while remaining the computational complexity same as in the time‐marching of first‐order methods. The discretization by employing the KDC method yields a boundary value problem of the inhomogeneous modified Helmholtz equation at each time step. The meshless generalized finite difference method (GFDM) or meshless finite difference method (MFDM), a meshless method, is then applied to the solution of resulting boundary value problems at each time step. Six numerical experiments in one‐, two‐, and three‐dimensional cases show that the proposed hybrid KDC‐GFDM scheme allows big time step size for a long‐time dynamic simulation and has a great potential for the problems with complex boundaries. In addition, some comparisons are also presented between the present method, the COMSOL software, and the GFDM with implicit Euler method.
Comparing fill and floor: A taphonomic framework for understanding depositional histories in a semi‐subterranean house in north‐west Alaska
Authors: Norman Lauren E.Y. 
Published: August 2018

AbstractCollapsed semi‐subterranean dwelling features are often excellent sources for well‐preserved faunal, artefactual, and architectural material in the Arctic. However, collapsed structures may be reused after house abandonment as storage areas, hunting blinds, refuse areas, or other resource facilities. Despite their reuse and possibly different occupation period, artefacts and faunal material from the fill are often employed, uncritically, to interpret the original house occupation. Within a Thule Inuit house depression, I employ an analytical framework as a heuristic device to compare the social nature of the various faunal deposits and the processes that affected them. Analyses show that the taphonomic processes alter the fill more extensively and intensively than the underlying floor. The floor shows little post‐depositional disturbance and is evidence for a cold‐season occupation. By contrast, the fill is a palimpsest of multiple occupations, some possibly related to the house occupation. Archaeologists need to differentiate fill from floor contexts when talking about the original occupation because the taphonomy of the two contexts indicate each is a distinct set of assemblages with differing operative processes.
Preparation of highly interconnected porous poly(ε‐caprolactone)/poly(lactic acid) scaffolds via supercritical foaming
Authors: Sun Shuhao , Li Qian , Zhao Na , Jiang Jing , Zhang Kangkang , Hou Jianhua , Wang Xiaofeng , Liu Guoji 
Published: August 2018

Highly interconnected porous polymer scaffolds were prepared by gas foaming. Poly(ε‐caprolactone)/poly(lactic acid) blends were melt mixed and batch foamed using CO2 as a physical blowing agent. The effects of the foaming temperature, pressure, and CO2 saturation time on the foam morphology were related to the mechanical properties of the scaffolds. The cell size in cross section of scaffolds decreased and became more homogeneous until CO2 saturation time reached 1.5 hours. With an increase in temperature, the cell size increased markedly and the cell size uniformity decreased gradually, whereas the reverse happened when the foaming pressure was increased. Meanwhile, many open cells can also be detected on the surface of scaffolds. High porosity and an open‐cell content of greater than 90% were obtained. The compressive strength of scaffolds was regulated by controlling the foam architecture. The information gathered in this study may provide a theoretical basis for research into porous tissue engineering scaffolds.
Evaluating automated approaches to anaphylaxis case classification using unstructured data from the FDA Sentinel System
Authors: Ball Robert , Toh Sengwee , Nolan Jamie , Haynes Kevin , Forshee Richard , Botsis Taxiarchis 
Published: August 2018

AbstractIntroductionIn May 2008, the Food and Drug Administration launched the Sentinel Initiative, a multi‐year program for the establishment of a national electronic monitoring system for medical product safety that led, in 2016, to the launch of the full Sentinel System. Under the Mini‐Sentinel pilot, several algorithms for identifying health outcomes of interest, including one for anaphylaxis, were developed and evaluated using data available from the Sentinel common data model.PurposeTo evaluate whether features extracted from unstructured narrative data using natural language processing (NLP) could be used to classify anaphylaxis cases.MethodsUsing previously developed methods, we extracted features from unstructured narrative data using NLP and applied rule‐based and similarity‐based algorithms to identify anaphylaxis among 62 potential cases previously classified by human experts as anaphylaxis (N = 33), not anaphylaxis (N = 27), and unknown (N = 2).ResultsThe rule‐based and similarity‐based approaches demonstrated almost equal performance (recall 100% vs 100%, precision 60.3% vs 57.4%, F‐measure: 0.753 vs 0.729). Reasons for misclassification included the inability of the algorithms to make the same clinical judgments as human experts about the timing, severity, or presence of alternative explanations; and the identification of terms consistent with anaphylaxis but present in conditions other than anaphylaxis.ConclusionsAlthough precision needs to be improved before these algorithms could be used without human review, we demonstrated that applying rule‐based and similarity‐based algorithms to unstructured narrative information from clinical records can be used for classification of anaphylaxis in the Sentinel System. Further development and assessment of these methods in the Sentinel System are warranted.
Side chain length affects backbone dynamics in poly(3‐alkylthiophene)s
Authors: Zhan Pengfei , Zhang Wenlin , Jacobs Ian E. , Nisson David M. , Xie Renxuan , Weissen Albree R. , Colby Ralph H. , Moulé Adam J. , Milner Scott T. , Maranas Janna K. , Gomez Enrique D. 
Published: August 2018

ABSTRACTCharge transport in conjugated polymers may be governed not only by the static microstructure but also fluctuations of backbone segments. Using molecular dynamics simulations, we predict the role of side chains in the backbone dynamics for regiorandom poly(3‐alkylthiophene‐2,5‐diyl)s (P3ATs). We show that the backbone of poly(3‐dodecylthiophene‐2‐5‐diyl) (P3DDT) moves faster than that of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) as a result of the faster motion of the longer side chains. To verify our predictions, we investigated the structures and dynamics of regiorandom P3ATs with neutron scattering and solid state NMR. Measurements of spin‐lattice relaxations (T1) using NMR support our prediction of faster motion for side chain atoms that are farther away from the backbone. Using small‐angle neutron scattering (SANS), we confirmed that regiorandom P3ATs are amorphous at about 300 K, although microphase separation between the side chains and backbones is apparent. Furthermore, quasi‐elastic neutron scattering (QENS) reveals that thiophene backbone motion is enhanced as the side chain length increases from hexyl to dodecyl. The faster motion of longer side chains leads to faster backbone dynamics, which in turn may affect charge transport for conjugated polymers. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1193–1202
Synthesis of Highly Fluorescent Yellow‐Green N‐Doped Carbon Nanorings for pH Variation Detection and Bioimaging
Authors: Xu Quan , Su Rigu , Zhong Jian , Zhang Lipeng , Guo Yongjian , Street Jason , Chen Yusheng , Cai Lulu , Tang Peifu 
Published: August 2018

AbstractA facile and direct chemical route is developed to produce intercrossed N‐doped graphene carbon nanorings (N‐CNRs) with a high yellow‐green photoluminescence emission in both solid and aqueous states. The N‐CNRs are directly synthesized at an elevated temperature in an inert atmosphere without additional pressure using urea and sodium citrate as raw materials. N‐CNRs have a photoluminescence change phenomenon from green to blue when the pH is altered from a neutral to a base value. The luminescence mechanism is analyzed under absorbance and lifetime decay, X‐ray photoelectron spectra, and X‐ray absorption near edge structure spectroscopy. Results indicate how the optical properties are tuned. The fluorescence bioimaging of zebrafish using N‐CNRs as the probe is also studied in terms of zebrafish husbandry, embryo harvesting, and the introduction of N‐CNRs into embryos and juveniles by soaking and microinjection. The prepared N‐CNRs serve as a promising fluorescent probe for pH variation analysis, and bioimaging. The N‐CNTs show potential for use in air purification applications.
TGF‐β receptor I inhibitor enhances response to enzalutamide in a pre‐clinical model of advanced prostate cancer
Authors: Paller Channing , Pu Hong , Begemann Diane E. , Wade Cameron A. , Hensley Patrick J. , Kyprianou Natasha 
Published: August 2018

BackgroundProstate cancer progression is navigated by the androgen receptor (AR) and transforming‐growth factor‐β (TGF‐β) signaling. We previously demonstrated that aberrant TGF‐β signaling accelerates prostate tumor progression in a transgenic mouse model of prostate cancer via effects on epithelial‐mesenchymal transition (EMT), driving castration‐resistant prostate cancer (CRPC).MethodsThis study examined the antitumor effect of the combination of TGF‐β receptor I (TβRI) inhibitor, galunisertib, and FDA‐approved antiandrogen enzalutamide, in our pre‐clinical model. Age‐matched genotypically characterized DNTGFβRII male mice were treated with either galunisertib and enzalutamide, in combination or as single agents in three “mini”‐trials and the effects on tumor growth, phenotypic EMT, and actin cytoskeleton were evaluated.ResultsGalunisertib in combination with enzalutamide significantly suppressed prostate tumor growth, by increasing apoptosis and decreasing cell proliferation of tumor cell populations compared to the inhibitor as a monotherapy (P < 0.05). The combination treatment dramatically reduced cofilin levels, actin cytoskeleton regulator, compared to single agents. Treatment with galunisertib targeted nuclear Smad4 protein (intracellular TGF‐β effector), but had no effect on nuclear AR. Consequential to TGF‐β inhibition there was an EMT reversion to mesenchymal‐epithelial transition (MET) and re‐differentiation of prostate tumors. Elevated intratumoral TGF‐β1 ligand, in response to galunisertib, was blocked by enzalutamide.ConclusionOur results provide novel insights into the therapeutic value of targeting TGF‐β signaling to overcome resistance to enzalutamide in prostate cancer by phenotypic reprogramming of EMT towards tumor re‐differentiation and cytoskeleton remodeling. This translational work is significant in sequencing TGF‐β blockade and antiandrogens to optimize therapeutic response in CRPC.
Measurement and evaluation of the effect of vibration on fruits in transit—Review
Authors: Fernando Indika , Fei Jiangang , Stanley Roger , Enshaei Hossein 
Published: August 2018

Mechanical vibration is a prominent cause of produce damage in many postharvest fruit supply chains. Knowledge on the causes, occurrence, and mechanistic relationship of vibration to produce damage is important for systematic development of remedial actions. This review identifies and discusses the critical factors of vibration, their implications for fruit quality, and possible improvements to addressing the issue of fruit quality deterioration. Frequently reported mechanical damage types caused by vibration on fruits are scuffing, fruit rub, and skin bruising. A wide range of factors can significantly affect the vibration intensity and thus resultant mechanical damage. Critical frequencies of vibration in the range of 0 to 10 Hz, attributed to peak energy levels in the power spectrum, cause substantial damage in fruits. Greater vertical acceleration and transmission of vibration to the higher tiers in a stacked column of packages result in increased mechanical damage. Fruit packages stacked in the rear positions of trucks are also affected more by vibration. Produce transported in leaf spring trucks has a higher risk of damage when compared with air‐ride suspension trucks. Additionally increased road roughness, vehicle speed, and duration of exposure to vibration proliferate fruit damage. The effects of different inner packing methods and different package types on mechanical damage are less frequently investigated. More accurate characterization of mechanical damage caused by vibration and shocks and its reproduction by enhanced simulation methods will contribute to optimizing damage prevention mechanisms and further improving the quality of fruits in transit within the postharvest supply chain.
Development of a detection method for antisense oligonucleotides in mouse kidneys by matrix‐assisted laser desorption/ionization imaging mass spectrometry
Authors: Yokoi Hiroyuki , Kasahara Yuya , Obika Satoshi , Doi Takefumi , Kamada Haruhiko 
Published: August 2018

RationaleOligonucleotide therapeutics have recently gained much attention, but its pharmacokinetic evaluation methods are still not sufficient, and, in particular, more tools are needed to evaluate their tissue distribution and metabolites. We developed a matrix‐assisted laser desorption/ionization imaging mass spectrometry (MALDI‐IMS)‐based method to evaluate the tissue distribution of oligonucleotide therapeutics.MethodsWe used an antisense oligonucleotide containing locked nucleic acids (LNA‐A). Various washing protocols were examined using mouse kidney homogenate sections. Next, we applied a two‐step matrix preparation strategy. As a first step, 3‐hydroxypicolinic acid (3‐HPA) matrix containing citrate and amines was sprayed using an airbrush and subsequently 3‐HPA matrix containing citrate only was sprayed using the ImagePrep. Finally, kidney sections prepared from LNA‐A‐dosed mice were treated with our optimized method and analyzed with MALDI‐IMS.ResultsThe selected washing method made it possible to detect LNA‐A with MALDI‐IMS and, furthermore, our developed matrix pretreatment method enhanced signal intensity approximately two‐fold. MALDI‐IMS revealed that LNA‐A localized in a portion presumed to be the renal cortex. We also obtained information on LNA‐A metabolites, which showed the same distribution profile as LNA‐A in kidneys.ConclusionsThis study shows that MALDI‐IMS can be applied to evaluate the tissue distribution of oligonucleotide therapeutics. Our method can evaluate the tissue distribution along with metabolites and has the potential to help the development of novel oligonucleotide therapeutics.
On‐substrate derivatization for detection of highly volatile G‐series chemical warfare agents via paper spray mass spectrometry
Authors: Mach Phillip M. , Dhummakupt Elizabeth S. , Carmany Daniel O. , McBride Ethan M. , Busch Michael W. , Demond Paul S. , Rizzo Gabrielle M. , Hollinshead Donna E. , Glaros Trevor 
Published: August 2018

RationaleThe analysis of chemical warfare agents (CWAs) from ambient atmosphere presents an analytical challenge due to their ease of degradation and volatility. Herein is described a method for derivatizing CWAs directly onto a paper spray substrate prior to analysis. This derivatization allows for much longer times of analysis without sample degradation and with little to no sample preparation.MethodsDerivatization was performed using 2‐[(dimethylamino)methyl] phenol both in‐vial and directly on paper spray cartridges. Solution studies were carried out over time and samples were analyzed via liquid chromatography/tandem mass spectrometry (LC/MS/MS) operated in positive ion mode. Paper spray substrates impregnated with the derivatizing agent prior to CWA vapor capture were also analyzed over time using a mass spectrometer operated in positive ion mode.ResultsUse of 2‐[(dimethylamino)methyl] phenol as a paper spray substrate dopant enables derivatization of G‐series compounds into lower volatility complexes. The reaction occurs in solution and in the vapor phase. This new technique effectively traps and captures G‐series agents for analysis while extending the time for which the compound remains absorbed. The complex is highly suitable for direct analysis via paper spray mass spectrometry.ConclusionsDerivatization of paper spray substrates was shown to greatly increase the time for analysis of CWAs. This technique, combined with the vapor phase capture stage outlined previously, allows for rapid, quantitative CWA detection by paper spray ionization with little or no sample preparation.
Three‐dimensional numerical simulations of smooth, asymmetrically roughened, and baffled culverts for upstream passage of small‐bodied fish
Authors: Zhang Gangfu , Chanson Hubert 
Published: August 2018

AbstractTraditional box culvert designs lead to development of high velocity zones in the culvert barrel that often impede upstream migration of fish. Herein, three‐dimensional Reynolds‐averaged Navier‐Stokes (RANS)‐ and Large eddy simulation (LES)‐based computational fluid dynamics (CFDs) simulations were performed to compare the effectiveness of smooth, asymmetrically roughened, and corner‐baffled barrels, in creating low‐velocity zones (LVZs) and providing opportunity for upstream passage of small‐bodied fish. The results revealed distinctive benefits provided by the asymmetrically roughened and corner‐baffled barrels relative to the smooth barrel. Cross‐sectional asymmetry, corners, and obstructions are important factors that contribute to the generation of LVZs conducive to fish passage, albeit contiguity of LVZs is required, particularly for weak swimmers. The study demonstrates the adequacy and effectiveness of CFD models to complement traditional laboratory studies in understanding basic mechanisms beneficial to fish passage and to provide insights into future designs.
Effects of natal water dilution on the migration of Pacific salmon in a regulated river
Authors: Bett Nolan N. , Hinch Scott G. , Casselman Matthew T. 
Published: August 2018

AbstractAdult salmon are guided by chemical cues from their natal water during the spawning migration. Consequently, hydroelectric activities can have negative effects on adult salmon navigation if they alter the chemical properties of the homing environment. We conducted riverside experiments to examine the effects of natal water dilution resulting from hydroelectric operations on upstream navigation in a British Columbia river and the efficacy of current dilution management in providing clear migratory cues for two local populations of sockeye salmon (Oncorhynchus nerka) and a population of pink salmon (Oncorhynchus gorbuscha). We found that both sockeye populations exhibited behavioural preferences for pure natal water when compared with various levels of diluted natal water, whereas pink salmon, which spawn throughout the system and exhibit lower levels of natal site fidelity, appeared unaffected by natal water dilution. Our findings confirmed that current management operations were appropriate for ensuring timely migration to spawning grounds and highlight the potential effects of alterations to water odour properties on salmon migrations.
Inhibitors of sustainable consumption: Insights from university academic staff in southern Nigeria
Authors: Ukenna Stephen , Nkamnebe Anayo , Idoko Edwin 
Published: August 2018

AbstractSustainable consumption behavior is increasingly becoming a topical issue in most developing economies. The growing unfavorable ecological footprint of most developing countries, including Nigeria, is becoming of concern and needs to be managed or reduced through strategic policy prescription and marketing strategy. Thus, insight from factors inhibiting sustainable consumption behavior could be a primary source to trigger reductions. Nevertheless, fostering sustainable consumption behavior in southern Nigeria, where the phenomenon is relatively nascent, requires contemporary insights into the factors that inhibit consumers to adopt sustainable consumption behavior. This research examines factors that discourage consumers' adoption of sustainable consumption behavior in southern Nigeria and uses those factors to develop a theory. A self‐administered questionnaire was used to collect data from 3,495 academic staff in nine universities in southern Nigeria. Structural equation modeling with the aid of SmartPLS 2.0 software was used to analyze the causal model. Statistical support was found mainly for sustainability awareness as the most critical inhibitor. Other inhibitors with lesser significance are government regulation, price perception, and religious and social groups. The marketing management and public policy implications are discussed.