bluuebunny/crossref_metadata_2025 huggingface dataset:
Análise Da Aprendizagem Dos Estudantes Do Ensino Fundamental Ii E Do Médio De Uma Escola Estadual Do Município De Uruguaiana/Rs A Respeito De Conhecimentos Paleontológicos
Authors: Peres Bruno Peruzzi , Ramos Karina Dos Santos , Silva Ilda Maricle De Castro Da , Pessano Edward Frederico Castro
Published: October 2024

Para a ciência, a Paleontologia é o estudo da evolução da vida, responsável por contribuir muito para a contextualização, não apenas da ciência como um todo, mas também para o ensino da mesma. Por possuir um caráter interdisciplinar esta temática pode servir como um facilitador na formação de uma visão integrada e contextualizada dos estudantes sobre Ciência. Portanto, o objetivo desta pesquisa foi investigar as percepções de estudantes do ensino fundamental II e médio quanto ao tema Paleontologia no ensino de ciências, bem como os meios de divulgação e aprendizagem que os participantes tiveram contato a respeito do tema. O presente trabalho caracteriza-se por um estudo de caso de caráter qualitativo e exploratório-descritivo, através de uma pesquisa de campo, onde o público participante foi composto por estudantes do nono ano dos anos finais do ensino fundamental e terceiro ano do ensino médio de uma escola em questão. Inicialmente os estudantes responderam questionários que focavam em suas percepções quanto a Paleontologia, como o estudante tem contato com o conteúdo e se carece de presença no meio escolar. Os dados obtidos foram analisados seguindo o método de análise de conteúdo de Bardin, constituído por uma série de técnicas para obter maior compreensão de um conteúdo através de indicadores. Dentre as várias respostas, fora visto que mesmo com informações muito básicas a respeito da paleontologia, a maior parte dessas percepções vinham de meios digitais de divulgação ou mídias de entretenimento. Observou-se a grande presença das mídias populares como meio de contato dos estudantes quanto à Paleontologia, representando um padrão que poderia muito bem ser melhor explorado para a devida aprendizagem dos estudantes. Muitos conceitos equivocados e superficiais demonstravam ser baseados em muitas informações de senso comum, provavelmente perpetuado por conta de mídias sociais e de desinformação, algo que acaba não sendo problematizado para que haja algum tipo de reconstrução relacionada ao ensino e aprendizagem da paleontologia nas escolas. Dessa forma, se faz necessário oferecer subsídios para promover a importância do ensino paleontológico em práticas ou projetos educacionais, buscando despertar o interesse dos estudantes por essa importante área e a contextualização da ciência que este conhecimento constrói.
Philosophical Approaches To William Blake’s Revolutionary Vision
Authors: Rahaman Moshiur
Published: October 2024

This article delves into the intellectual facets of William Blake's imaginative universe, examining the numerous perspectives that can be used to understand his deep ideas. By concentrating on the philosophical underpinnings of Blake's unique vision, this study aims to investigate the intricate layers of his works from both a literary and philosophical standpoint. It is believed that the English poet Wordsworth observed, "I know this poor man was insane, but there's something about his madness that interests me more than Walter Scott's and Lord Byron's sanity. Blake's creative and literary works frequently broke free from conventional conventions and provided a visionary viewpoint that went beyond common sense perception. This essay explores Blake's philosophical legacy and the various ways in which his vision addresses creativity, reality, and spiritual expression through a thorough analysis of his works, especially The Marriage of Heaven and Hell and Jerusalem. This essay advances our knowledge of Blake's lasting impact and the great importance of his imaginative vision by examining the philosophical responses to his ideas. Readers are encouraged to discuss Blake's influence and the enduring value of his revolutionary philosophy.
Impact of Resolution on the Representation of Precipitation Variability Associated With the ITCZ
Authors: De Benedetti Marc , Moore G. W. K.
Published: December 2017

The Intertropical Convergence Zone (ITCZ) is responsible for most of the weather and climate in equatorial regions along with many tropical‐midlatitude interactions. It is therefore important to understand how models represent its structure and variability. Most ITCZ‐associated precipitation is convective, making it unclear how horizontal resolution impacts its representation. To assess this, we introduce a novel technique that involves calculation of the precipitation field's decorrelation length scale (DCLS) using model data sets that share a common lineage with horizontal resolutions from 16 to 160 km. All resolutions captured the ITCZ's mean structure; however, imprints of topography, such as Hawaii and sea surface temperature, including the variability associated with upwelling cold water off the coast of South America, are more clearly represented at higher resolutions. The DCLS analysis indicates that there are changes in the spatial variability of the ITCZ's precipitation that are not reflected in its mean structure, thus confirming its utility as a diagnostic.
Aerial Observations of Symmetric Instability at the North Wall of the Gulf Stream
Authors: Savelyev I. , Thomas L. N. , Smith G. B. , Wang Q. , Shearman R. K. , Haack T. , Christman A. J. , Blomquist B. , Sletten M. , Miller W. D. , Fernando H. J. S.
Published: December 2017

An unusual spatial pattern on the ocean surface was captured by thermal airborne swaths taken across a strong sea surface temperature front at the North Wall of the Gulf Stream. The thermal pattern on the cold side of the front resembles a staircase consisting of tens of steps, each up to ∼200 m wide and up to ∼0.3°C warm. The steps are well organized, clearly separated by sharp temperature gradients, mostly parallel and aligned with the primary front. The interpretation of the airborne imagery is aided by oceanographic measurements from two research vessels. Analysis of the in situ observations indicates that the front was unstable to symmetric instability, a type of overturning instability that can generate coherent structures with similar dimensions to the temperature steps seen in the airborne imagery. It is concluded that the images capture, for the first time, the surface temperature field of symmetric instability turbulence.
Intense Harmonic Emissions Observed in Saturn's Ionosphere
Authors: Sulaiman A. H. , Kurth W. S. , Persoon A. M. , Menietti J. D. , Farrell W. M. , Ye S.‐Y. , Hospodarsky G. B. , Gurnett D. A. , Hadid L. Z.
Published: December 2017

The Cassini spacecraft's first Grand Finale orbit was carried out in April 2017. This set of 22 orbits had an inclination of 63° with a periapsis grazing Saturn's ionosphere, thus providing unprecedented coverage and proximity to the planet. Cassini's Radio and Plasma Wave Science instrument repeatedly detected intense electrostatic waves and their harmonics near closest approach in the dayside equatorial topside ionosphere. The fundamental modes were found to both scale and trend best with the H+ plasma or lower hybrid frequencies, depending on the plasma composition considered. The fine‐structured harmonics are unlike previous observations, which scale with cyclotron frequencies. We explore their generation mechanism and show strong evidence of their association with whistler mode waves, consistent with theory. The possibility of Cassini's presence in the ionosphere influencing the resonance and harmonics is discussed. Given their link to the lower hybrid frequency, these emissions may offer clues to constraining Saturn's ionospheric properties.
Social and Structural Patterns of Drought‐Related Water Conservation and Rebound
Authors: Gonzales Patricia , Ajami Newsha
Published: December 2017

Water use practices and conservation are the result of complex sociotechnical interactions of political, economic, hydroclimatic, and social factors. While the drivers of water demand have been extensively studied, they have traditionally been applied to models that assume stationary relationships between these various factors, and usually do not account for potential societal changes in response to increased scarcity awareness. For example, following a period of sustained low demand such as during a drought, communities often increase water use during a hydrologically wet period, a phenomenon known as “rebounding” water use. Previous experiences show the extent of this rebound is not a straightforward function of policy and efficiency improvements, but may also reflect short‐term or long‐lasting change in community behavior, which are not easily captured by models that assume stationarity. In this work, we develop a system dynamics model to represent water demand as a function of both structural and social factors. We apply this model to the analysis of three diverse water utilities in the San Francisco Bay Area between 1980 and 2017, identifying drought response trends and drivers over time. Our model is consistent with empirical patterns and historical context of water use in California, and provides important insights on the rebound phenomenon that can be extended to other locations. This comparative assessment indicates that policies, public outreach, and better data availability have played a key role in raising public awareness of water scarcity, especially with the raise of the internet era in recent years.
miRNAexpression profile of retinal pigment epithelial cells under oxidative stress conditions
Authors: Donato Luigi , Bramanti Placido , Scimone Concetta , Rinaldi Carmela , D'Angelo Rosalia , Sidoti Antonina
Published: December 2017

Deep analysis of regulative mechanisms of transcription and translation in eukaryotes could improve knowledge of many genetic pathologies such as retinitis pigmentosa (RP). New layers of complexity have recently emerged with the discovery that ‘junk’ DNA is transcribed and, among these, miRNAs have assumed a preponderant role. We compared changes in the expression of miRNAs obtained from whole transcriptome analyses, between two groups of retinal pigment epithelium (RPE) cells, one untreated and the other exposed to the oxidant agent oxidized low‐density lipoprotein (oxLDL), examining four time points (1, 2, 4 and 6 h). We found that 23 miRNAs exhibited altered expression in the treated samples, targeting genes involved in several biochemical pathways, many of them associated to RP for the first time, such as those mediated by insulin receptor signaling and son of sevenless. Moreover, five RP causative genes (KLHL7, RDH11, CERKL, AIPL1 and USH1G) emerged as already validated targets of five altered miRNAs (hsa‐miR‐1307, hsa‐miR‐3064, hsa‐miR‐4709, hsa‐miR‐3615 and hsa‐miR‐637), suggesting a tight connection between induced oxidative stress and RP development and progression. This miRNA expression analysis of oxidative stress‐induced RPE cells has discovered new regulative functions of miRNAs in RP that should lead to the discovery of new ways to regulate the etiopathogenesis of RP.
Foot Barriers in Patients With Early Rheumatoid Arthritis: An Interview Study Among Swedish Women and Men
Authors: Björk Mathilda , Thyberg Ingrid , Valtersson Eva , Östlund Gunnel , Stenström Birgitta , Sverker Annette
Published: December 2017

Objective

Foot impairments are related to reduced mobility and participation restrictions in daily activities in patients with established rheumatoid arthritis (RA). The new biologic medications are effective and reduce disease activity, but not disability to the same extent. Foot impairments are assumed to be related to participation restrictions also in patients with early RA, diagnosed after the introduction of biologic medications. Knowledge of foot impairments needs to be explored further after the introduction of biologic disease‐modifying antirheumatic drugs (bDMARDs). The aim of this study was to explore the patients’ perspective of foot impairments related to early RA.

Methods

The sample included 59 patients (ages 20–63 years) who were interviewed about participation dilemmas in daily life using the critical incident technique. The interviews were audio‐recorded and transcribed. Data related to foot impairments were extracted and analyzed thematically. A research partner validated the analysis.

Results

Patients with early RA described a variety of participation restrictions related to foot impairments: foot hindrances in domestic life, foot impairments influencing work, leisure activities restricted by one's feet, struggling to be mobile, and foot impairments as an early sign of rheumatic disease.

Conclusion

There is a need to focus on foot impairments related to early RA, and for health care professionals to understand these signs. A suggestion for future research is to conduct a longitudinal followup of foot impairment related to medication, disease activity, and disability in patients diagnosed after the introduction of bDMARDs.
Strong SERS Performances of Ultrathin α‐Co(OH)2 Nanosheets to the Toxic Organophosphorus Molecules and Hydrogen Bond‐Induced Charge Transfer Mechanism
Authors: Zhao Qian , Liu Guangqiang , Zhang Hongwen , Li Yue , Cai Weiping
Published: December 2017

The ultrathin α‐Co(OH)2 nanosheets are fabricated via homogeneous precipitation from the cobalt nitrate solution. The nanosheet‐built film is used as the substrate for Raman detection of toxic organophosphorus molecules. Such nanosheets are of strong surface enhancement Raman scattering (SERS) effect to the molecules that can be captured by the hydroxyls on the nanosheets. The enhancement factor is up to 2.0 × 103. Typically, for the triphenylphosphine oxide (TPPPO) and 3,3‐diethylthiatricarbocyanine iodide (DTTCI) which both can be used as hydrogen bond acceptors and form hydrogen bonds with α‐Co(OH)2 on the nanosheets' surface, the detection are to 0.35 ppm. The Raman peak intensity shows a linear relation with logarithmic DTTCI concentration, due to Temkin adsorption of DTTCI molecules on the nanosheets, and exhibits a linear double logarithmic relation with TPPPO concentration, due to Freundlich‐type adsorption. Further analysis reveal that such enhancement effect is attributed to the hydrogen bond‐induced formation of new excited state in the test molecules, which induces the charge transfer and hence magnifies the test molecules' polarizability. This work not only provides an effective substrate for SERS‐based detection of toxic organophosphorus molecules but also presents a new approach to design of the highly efficient nonmetal SERS‐active materials.
Synthesis of Carbon Nanotube Incorporated Metal Oxides for the Fabrication of Printable, Flexible Nickel‐Zinc Batteries
Authors: Wang Zhiqian , Meng Xianyang , Chen Kun , Mitra Somenath
Published: December 2017

The development of printable composite electrodes embedded with multiwalled carbon nanotubes (CNTs) for flexible nickel‐zinc batteries is presented. The cathode and the anode comprised of Ni(OH)2‐CNT and ZnO‐CNT respectively are prepared by coprecipitation of the metal oxides on CNTs. High loading ratio of electroactive materials increases the amount of active materials in electrode, but causes a lower material utilization efficiency due to decrease in overall electrode conductivity. The direct loading of active materials onto CNTs enhances contact where the CNTs serve the pathways for electron transport leading to higher performance than physical mixing of active ingredients. The cells show good performance even under bending conditions and the overall technology is scalable by printing methods.
Lithographically Designed Conical Microcarriers for Programed Release of Multiple Actives
Authors: Je Kwanghwi , Kim Ju Hyeon , Shim Tae Soup , Ku Minhee , Yang Jaemoon , Kim Shin‐Hyun
Published: December 2017

The programed release of multiple ingredients is important in the therapeutics and pharmaceutical fields. A variety of core–shell microcarriers have been designed to fulfill the release function; however, encapsulating multiple actives in their own compartments and releasing them in a programed manner remains a challenge due to restrictions on the material sets that may be used to form the compartments. In this work, the development of lithographically featured core–shell microcarriers composed of double cones and a cap that encapsulate and release various combinations of multiactives in a predefined fashion is reported. Active‐free caps are first prepared on a photomask using conventional photolithography. Onto each cap, sequentially, an active‐loaded small cone and large cone in two steps of reaction–diffusion‐mediated photolithography (RDP) are formed. The release kinetics of the actives stored in the inner and outer cones are controlled by tailoring the crosslinking density of the photocured polymers that composed each compartment. The cap prevents direct diffusion from the inner cone to the surrounding. The RDP‐based lithographic means for creating core–shell microcarriers provides new opportunities for delivering synergistic combinations of drugs in pharmacotherapy.
Ultrahigh, Ultrafast, and Self‐Powered Visible‐Near‐Infrared Optical Position‐Sensitive Detector Based on a CVD‐Prepared Vertically Standing Few‐Layer MoS2/Si Heterojunction
Authors: Cong Ridong , Qiao Shuang , Liu Jihong , Mi Jiansong , Yu Wei , Liang Baolai , Fu Guangsheng , Pan Caofeng , Wang Shufang
Published: December 2017

MoS2, as a typical transition metal dichalcogenide, has attracted great interest because of its distinctive electronic, optical, and catalytic properties. However, its advantages of strong light absorption and fast intralayer mobility cannot be well developed in the usual reported monolayer/few‐layer structures, which make the performances of MoS2‐based devices undesirable. Here, large‐area, high‐quality, and vertically oriented few‐layer MoS2 (V‐MoS2) nanosheets are prepared by chemical vapor deposition and successfully transferred onto an Si substrate to form the V‐MoS2/Si heterojunction. Because of the strong light absorption and the fast carrier transport speed of the V‐MoS2 nanosheets, as well as the strong built‐in electric field at the interface of V‐MoS2 and Si, lateral photovoltaic effect (LPE) measurements suggest that the V‐MoS2/Si heterojunction is a self‐powered, high‐performance position sensitive detector (PSD). The PSD demonstrates ultrahigh position sensitivity over a wide spectrum, ranging from 350 to 1100 nm, with position sensitivity up to 401.1 mV mm−1, and shows an ultrafast response speed of 16 ns with excellent stability and reproducibility. Moreover, considering the special carrier transport process in LPE, for the first time, the intralayer and the interlayer transport times in V‐MoS2 are obtained experimentally as 5 and 11 ns, respectively.
A Pickering Emulsion Route to Swimming Active Janus Colloids
Authors: Archer Richard J. , Parnell Andrew J. , Campbell Andrew I. , Howse Jonathan R. , Ebbens Stephen J.
Published: December 2017

The field of active colloids is attracting significant interest to both enable applications and allow investigations of new collective colloidal phenomena. One convenient active colloidal system that has been much studied is spherical Janus particles, where a hemispherical coating of platinum decomposes hydrogen peroxide to produce rapid motion. However, at present producing these active colloids relies on a physical vapor deposition (PVD) process, which is difficult to scale and requires access to expensive equipment. In this work, it is demonstrated that Pickering emulsion masking combined with solution phase metallization can produce self‐motile catalytic Janus particles. Comparison of the motion and catalytic activity with PVD colloids reveals a higher catalytic activity for a given thickness of platinum due to the particulate nature of the deposited coating. This Pickering emulsion based method will assist in producing active colloids for future applications and aid experimental research into a wide range of active colloid phenomena.
Photoinduced Rapid Transformation from Au Nanoagglomerates to Drug‐Conjugated Au Nanovesicles
Authors: Poudel Bijay Kumar , Kim Jong Oh , Byeon Jeong Hoon
Published: December 2017

Gold (Au) agglomerates (AGs) are reassembled using Triton X‐100 (T) and doxorubicin (D) dissolved in ethanol under 185 nm photoirradiation to form TAuD nanovesicles (NVs) under ambient gas flow conditions. The positively charged Au particles are then electrostatically conjugated with the anionic chains of TD components via a flowing drop (FD) reaction. Photoirradiation of the droplets in a tubular reactor continues the photophysicochemical reactions, resulting in the reassembly of Au AGs and TD into TAuD NVs. The fabricated NVs are electrostatically collected onto a polished aluminum rod in a single‐pass configuration. The dispersion of NVs is employed for bioassays to confirm uptake by cells and accumulation in tumors. The chemo‐photothermal activity is determined both in vitro and in vivo. Different combinations of components are also used to fabricate NVs using the FD reaction, and these NVs are suitable for gene delivery as well. This newly designed gaseous single‐pass process results in the reassembly of Au AGs for incorporation with TD without the need of batch wet chemical reactions, modifications, separations, or purifications. Thus, this process offers an efficient platform for preparing biofunctional Au nanostructures that requires neither complex physicochemical steps nor special storage techniques.
Titania‐Coated Gold Nano‐Bipyramids for Blocking Autophagy Flux and Sensitizing Cancer Cells to Proteasome Inhibitor‐Induced Death
Authors: Wan Hong‐Ye , Chen Jian‐Li , Zhu Xingzhong , Liu Liang , Wang Jianfang , Zhu Xiao‐Ming
Published: December 2017

Targeting protein degradation is recognized as a valid approach to cancer therapy. The ubiquitin–proteasome system (UPS) and the autophagy–lysosome pathway are two major pathways for intracellular protein degradation. Proteasome inhibitors such as bortezomib are clinically approved for treating malignancies, but to date, they are still unsatisfactory for cancer therapy. This study identifies titania‐coated gold nano‐bipyramid (NBP/TiO2) nanostructures as an autophagic flux inhibitor, as the smallest NBP/TiO2 nanostructures induce significant autophagosome accumulation in human glioblastoma U‐87 MG cells via blocking the autophagosome–lysosome fusion process and inhibiting lysosomal degradation. Further study indicates that NBP/TiO2 nanostructures reduce the intracellular level of mature cathepsin B and directly inhibit the proteolytic activity of cathepsin B, thereby further inhibiting trypsin‐like proteolytic activity, which is a potential cotarget for UPS inhibition. NBP/TiO2 nanostructures interact synergistically with bortezomib to suppress the viability of U‐87 MG cells, as the combined treatment synergistically induces the intracellular accumulation of ubiquitinated protein and endoplasmic reticulum stress. In addition, photothermal therapy further synergistically reduces the cell viability. In summary, this study suggests that NBP/TiO2 nanostructures function as a promising anticancer agent in combination with proteasome inhibitors.
Stimuli‐Directed Dynamic Reconfiguration in Self‐Organized Helical Superstructures Enabled by Chemical Kinetics of Chiral Molecular Motors
Authors: Sun Jian , Lan Ruochen , Gao Yanzi , Wang Meng , Zhang Wanshu , Wang Ling , Zhang Lanying , Yang Zhou , Yang Huai
Published: December 2017

Dynamic controllability of self‐organized helical superstructures in spatial dimensions is a key step to promote bottom‐up artificial nanoarchitectures and functional devices for diverse applications in a variety of areas. Here, a light‐driven chiral overcrowded alkene molecular motor with rod‐like substituent is designed and synthesized, and its thermal isomerization reaction exhibits an increasing structural entropy effect on chemical kinetic analysis in anisotropic achiral liquid crystal host than that in isotropic organic liquid. Interestingly, the stimuli‐directed angular orientation motion of helical axes in the self‐organized helical superstructures doped with the chiral motors enables the dynamic reconfiguration between the planar (thermostationary) and focal conic (photostationary) states. The reversible micromorphology deformation processes are compatible with the free energy fluctuation of self‐organized helical superstructures and the chemical kinetics of chiral motors under different conditions. Furthermore, stimuli‐directed reversible nonmechanical beam steering is achieved in dynamic hidden periodic photopatterns with reconfigurable attributes prerecorded with a corresponding photomask and photoinduced polymerization.
Extending the range of COSMO‐SAC to high temperatures and high pressures
Authors: Silveira Christian L. , Sandler Stanley I.
Published: December 2017

The range of the predictive Gibbs energy of solvation model, COSMO‐SAC, is extended to large ranges of density, pressure, and temperature for very nonideal mixtures by combining it with an equation of state (EOS) using the Wong‐Sandler mixing rule. The accuracy of isothermal vapor‐liquid equilibria (VLE) calculations based on using the predictive COSMO‐SAC model and separately the correlative NRTL model is compared, each combined with three different forms of the Peng‐Robinson equation of state. All the models considered require the value of the EOS mixing rule binary parameter kij. The NRTL model also requires three other parameters obtained from correlation low pressure VLE data. The PRSV + COSMO‐SAC model is showed, with its one adjustable parameter obtained from low temperature data leads good predictions at much higher temperatures and pressures. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1806–1813, 2018
para‐Xylene Ultra‐selective Zeolite MFI Membranes Fabricated from Nanosheet Monolayers at the Air–Water Interface
Authors: Kim Donghun , Jeon Mi Young , Stottrup Benjamin L. , Tsapatsis Michael
Published: December 2017

The control of membrane morphology and microstructure is crucial to improve the separation performance of molecular‐sieve membranes. This can be enabled by making thin, dense, and uniform seed‐crystal coatings, which are then intergrown into continuous membranes. Herein, we show a novel and simple floating particle coating method can give closely packed monolayers of zeolite nanosheets on nonporous or porous supports. The zeolite nanosheet monolayer is formed at the air–water interface in a conical Teflon trough. As the water in the trough is drained, the monolayer is deposited on a support placed below. Membranes prepared by gel‐free secondary growth of the nanosheets deposited by this method show unprecedented ultra‐selective performance for separation of para‐ from ortho‐xylene (separation factor >10 000).
The Hydrogen Evolution Reaction in Alkaline Solution: From Theory, Single Crystal Models, to Practical Electrocatalysts
Authors: Zheng Yao , Jiao Yan , Vasileff Anthony , Qiao Shi‐Zhang
Published: December 2017

The hydrogen evolution reaction (HER) is a fundamental process in electrocatalysis and plays an important role in energy conversion for the development of hydrogen‐based energy sources. However, the considerably slow rate of the HER in alkaline conditions has hindered advances in water splitting techniques for high‐purity hydrogen production. Differing from well documented acidic HER, the mechanistic aspects of alkaline HER are yet to be settled. A critical appraisal of alkaline HER electrocatalysis is presented, with a special emphasis on the connection between fundamental surface electrochemistry on single‐crystal models and the derived molecular design principle for real‐world electrocatalysts. By presenting some typical examples across theoretical calculations, surface characterization, and electrochemical experiments, we try to address some key ongoing debates to deliver a better understanding of alkaline HER at the atomic level.
Compressive response of PMMA microcellular foams at low and high strain rates
Authors: Zhang Ruizhi , Zhang Lianmeng , Zhang Jian , Luo Guoqiang , Xiao Dawu , Song Zhenfei , Li Meijuan , Xiong Yuanlu , Shen Qiang
Published: December 2017

Microcellular foams are widely applied in various applications in both civil and military applications for barriers and energy absorption materials. Poly(methyl methacrylate) microcellular foams were fabricated via supercritical foaming method. Field emission scanning electron microscopy, differential scanning calorimetry, and mechanical test machine were used to visualize the foam structure and test the quasi‐static compression properties. Moreover, Split Hopkinson Bar (SHPB) setups were adopted to explore the dynamic compression properties. The experimental results show that the microcellular foams have homogeneous cell size distribution and exhibit superior compressive behavior at both quasi‐static and high strain rates. The mechanical properties depend on both foam density and strain rate. Strain rate effects are clearly observed. At quasi‐static strain rate and 7500 S−1 regime, cell wall bucking and folding are the main failure mechanism. However, at high strain rate regime, softening phenomenon is observed. By roughly calculating the energy absorbed and the temperature rise, the temperature of the foams will rise up to as high as 130 °C after conducting high strain rate compression, and it is postulated that the generated heat will destroy the cell structure of the foams. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46044.
Electromagnetic emissivity of hot and dense matter
Authors: Bratkovskaya E.L. , Cassing W. , Linnyk O.
Published: December 2017

The Quantum‐Chromo Dynamics (QCD) matter produced initially in ultrarelativistic nucleus–nucleus collisions is expected to represent a high temperature plasma, which should be evidenced in its electromagnetic radiation. We analyze the production of real and virtual photons from the strongly coupled Quark‐Gluon Plasma (QGP) in the initial stages of the collisions as well as the (“corona”) radiation from the interacting mesons and baryons after hadronization using the parton‐hadron‐string dynamics (PHSD) transport approach. The description of the bulk evolution in the microscopic PHSD approach has been independently controlled by abundances, spectra, and flow of final particles and is found to be in agreement with experimental observation. In this study, we provide a brief description of the relevant physics assumptions within the PHSD approach and give details on the implementation of real and virtual photon radiation in partonic and hadronic interactions and decays. Our calculations have been found to successfully describe the production of photons and dileptons in proton–proton as well as nucleus–nucleus collisions in a wide range of bombarding energies as well.
Boson star solutions of the Einstein–Klein–Gordon equations in the sense of Colombeau–Egorov's theory of generalized functions
Authors: Cabo Montes de Oca A. , Suárez Fontanella D. , Cabo Bizet N. G.
Published: December 2017

We present static, spherically symmetric solutions of the equations of motion of a scalar field interacting with gravity through the Einstein–Klein–Gordon (EKG) equations in the Colombeau–Egorov sense. The scalar fields are confined within the interior region of the solution, and the exterior fields are purely gravitational and coinciding with the Schwarzschild ones. The solution resembles the so‐called gravastars discussed in the literature. The presented solutions of the EKG equations open the possibility for the existence of static boson stars. The argument is based on defining an infinitely differentiable one‐parameter (ϵ‐dependent) family of radial dependencies of the metric and the scalar field. It is shown that in the limit ϵ → 0, the EKG equations are satisfied in the sense of the generalized functions. The solutions exhibit properties that qualitatively support their physical meaning. For example, close to the boundary at the interior, the scalar field energy density piles up toward the limit surface. On the other hand, also close to the separation surface but on the outside, the known “non‐hair” theorem clearly indicates that any scalar field perturbation also tends to be attracted to the boundary. The work also suggests the possibility for obtaining a regular gravastar, after using the singular configuration found as a first step in an iterative solution of the quantum EKG equations.
Extragalactic magnetic fields revealed
Authors: Urban F. R.
Published: December 2017

In this paper, the strongest limits, obtained from rotation measures on cosmological magnetic fields, are presented.
Accuracy of birth certificate head circumference measurements: Massachusetts, 2012–2013
Authors: Somerville Nicholas J. , Chen Xiaoli , Heinke Dominique , Stone Sarah L. , Higgins Cathleen , Manning Susan E. , Pagnano Sharon , Yazdy Mahsa M. , Anderka Marlene
Published: December 2017

Background

Zika virus has recently emerged as a novel cause of microcephaly. CDC has asked states to rapidly ascertain and report cases of Zika‐linked birth defects, including microcephaly. Massachusetts added head circumference to its birth certificate (BC) in 2011. The accuracy of head circumference measurements from state vital records data has not been reported.

Methods

We sought to assess the accuracy of Massachusetts BC head circumference measurements by comparing them to measurements for 2,217 infants born during 2012–2013 captured in the Massachusetts Birth Defects Monitoring Program (BDMP) data system. BDMP contains information abstracted directly from infant medical records and served as the true head circumference value (i.e., gold standard) for analysis. We calculated the proportion of head circumference measurements in agreement between the BC and BDMP data. We assigned growth chart head circumference percentile categories to each BC and BDMP measurement, and calculated the sensitivity and specificity of BC‐based categories to predict BDMP‐based categories.

Results

No difference was found in head circumference measurements between the two sources in 77.9% (n = 1,727) of study infants. The sensitivity of BC‐based head circumference percentile categories ranged from 85.6% (<3rd percentile) to 92.7% (≥90th percentile) and the specificity ranged from 97.6% (≥90th percentile) to 99.3% (<3rd percentile).

Conclusions

BC head circumference measurements agreed with those abstracted from the medical chart the majority of the time. Head circumference measurements on the BC were more specific than sensitive across all standardized growth chart percentile categories.
Total prevention of folic acid‐preventable spina bifida and anencephaly would reduce child mortality in India: Implications in achieving Target 3.2 of the Sustainable Development Goals
Authors: Kancherla Vijaya , Oakley Godfrey P.
Published: December 2017

Background

The potential to reduce child mortality by preventing folic acid‐preventable spina bifida and anencephaly (FAP SBA) is inadequately appreciated. To quantify possible reduction in FAP SBA‐associated child mortality in low‐ and middle‐income countries, we conducted an analysis to demonstrate in India, a country with more than 25 million births and 1.2 million under‐five deaths each year, the decrease in neonatal, infant, and under‐five mortality that would occur through total prevention of FAP SBA.

Methods

We estimated the percent reductions in neonatal, infant, and under‐five mortality that would have occurred in India in 2015 had all of FAP SBA been prevented. We also estimated the contributions of these reductions toward India's Sustainable Development Goals on child mortality indicators. We considered the overall prevalence of spina bifida and anencephaly in India as 5 per 1,000 live births, of which 90% were preventable with effective folic acid intervention.

Results

In the year 2015, folic acid interventions would have prevented about 116,070 cases of FAP SBA and 101,565 under‐five deaths associated with FAP SBA. Prevention of FAP SBA would have reduced annually, neonatal, infant, and under‐five mortality by 10.2%, 8.9%, and 8.3%, respectively. These reductions would have contributed 18.5% and 17.2% to the reductions in neonatal and under‐five mortality, respectively, needed by India to achieve its 2030 Sustainable Developmental Goal Target 3.2 addressing preventable child mortality.

Conclusions

Total prevention of FAP SBA clearly has a significant potential for immediate reductions in neonatal, infant, and under‐five mortality in India, and similarly other countries.
Viability Studies of Cells on Nanostructured Surfaces With Various Feature Sizes
Authors: Kim Geun‐Oh , Lee Hoyeon , Ma Eungyung , Kang Chulhun , Kwon Young‐Uk
Published: December 2017

We demonstrate that the pore size of a nanoporous anodic aluminum oxide (AAO) membrane is critical for cell viability and cell adhesion upon HeLa cell growth on it, while other properties of membranes such as surface wettability and pore fraction show no such effects. After a human cancer cell, HeLa cell line, was seeded on AAO membranes with various pore sizes ranging from 18 to 150 nm, the adhered cell population and 3‐(4,5‐dimethyltiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay were measured. The cell adhesion and viability on the membrane with small pores (18 nm) were similar to those on the nonporous reference; however, they gradually decreased as the pore size increased. The decreased viability involves cell death as well as poor cell adhesion. We found that cyclo(l‐arginylglycyl‐l‐α‐aspartyl‐d‐phenylalanyl‐l‐cysteinyl), a well‐known integrin receptor antagonist, drastically decreased the cell adhesion to the membranes. The data indicate that the cell adhesion to the nanoporous membranes may be mediated by integrin on the cell surface, plausibly explaining the pore size dependence of the cell adhesion and viability. Implications of the present results to related fields such as implants are discussed.
The Effect of Copper Loading on Iron Carbide Formation and Surface Species in Iron‐Based Fischer–Tropsch Synthesis Catalysts
Authors: Peña Diego , Jensen Lise , Cognigni Andrea , Myrstad Rune , Neumayer Thomas , van Beek Wouter , Rønning Magnus
Published: December 2017

The effect of copper as promoter on iron carbide formation and the nature of surface species on iron‐based catalyst during Fischer–Tropsch synthesis (FTS) was investigated. Iron‐based catalysts (15 wt % of Fe) supported on alumina promoted with copper (0, 0.6, 2, and 5 wt %) were characterised in situ at relevant FTS conditions. The catalysts promoted with 2 and 5 wt % of Cu showed higher catalytic activity due to the formation of Hägg carbide (Fe5C2) detected by in situ XANES and XRD. The carbide formation is attributed to a weakening of the iron–alumina mixed‐compound interactions, and hence increasing iron reducibility and dispersion. The in situ XANES measurements indicated a maximum carburization degree (ca. 20–22 %) even at high Cu loading. The catalyst promoted with 5 wt % of Cu exhibited higher water‐gas shift activity. Aliphatic hydrocarbons, formate, and carboxylate species were detected on the catalyst surface during FTS. After exposing the spent catalysts to hydrogenation conditions, the carboxylate species remained strongly adsorbed while aliphatic hydrocarbons and formate species disappeared. The accumulation of oxygenates species on the catalyst surface increased with Cu loading. The interaction of oxygenates with alumina and iron oxide particles (FexOy) were revealed, with the latter being a possible reason for inhibition of further iron carburization.
Crystal Structures and Phase Behavior of Sulfadiazine and a Method for the Preparation of Aggregates with Good Performance
Authors: Wu Songgu , Du Shichao , Chen Mingyang , Li Kangli , Jia Lina , Zhang Dejiang , Macaringue Estevao G. J. , Hou Baohong , Gong Junbo
Published: December 2017

The solvate and the solvent‐free form of sulfadiazine (SD) were investigated. SD was found to exist in one solvent‐free form and the N‐methylpyrrolidone (NMP) solvate form. The NMP solvate was shown to be a channel‐type compound. The intrinsic properties of the solvents were used to evaluate the effects of solubility on the phase transformation of SD and the NMP solvate. The SD phase could transform to the NMP solvate by NMP‐mediated phase transformation, which was governed by crystallization of the NMP solvate. The crystalline NMP solvate could transform to the solvent‐free solid state through solid‐solid transformation upon heating or water penetration‐mediated phase transformation. The rate of this water penetration‐mediated phase transformation of the NMP solvate to SD was unusually fast. It can be used to obtain SD aggregates of well‐defined shape and good powder properties.
An improved plant‐wide fault detection scheme based on PCA and adaptive threshold for reliable process monitoring: Application on the new revised model of Tennessee Eastman process
Authors: Bakdi Azzeddine , Kouadri Abdelmalek
Published: December 2017

An improved process monitoring scheme is presented in this paper, it is based on the integration of multivariate and univariate statistical analysis methods. Instead of conventional fixed control limits, adaptive thresholds are developed for common fault detection indices used with principal component analysis, including the Hotelling T2 statistic and the sum of squared prediction error known as the Q statistic. The thresholds are updated based on a modified exponentially weighted moving average chart with a limited window length. The primary goal of this strategy is to enhance the performance of principal component analysis–based process monitoring method and overcome its shortcomings, by increasing fault detection rate to improve monitoring sensitivity and eliminating false alarms to ensure higher robustness and reliability. Fault detection in the revised model of Tennessee Eastman process benchmark is also investigated. The developed monitoring scheme is tested and compared with conventional fixed threshold technique, and its performance is evaluated across various types of process faults. The obtained results demonstrate the promising capabilities of the developed scheme.
Preparation of a Si/SiO2–Ordered‐Mesoporous‐Carbon Nanocomposite as an Anode for High‐Performance Lithium‐Ion and Sodium‐Ion Batteries
Authors: Zeng Lingxing , Liu Renpin , Han Lei , Luo Fenqiang , Chen Xi , Wang Jianbiao , Qian Qingrong , Chen Qinghua , Wei Mingdeng
Published: December 2017

In this work, an Si/SiO2–ordered‐mesoporous carbon (Si/SiO2–OMC) nanocomposite was initially fabricated through a magnesiothermic reduction strategy by using a two‐dimensional bicontinuous mesochannel of SiO2–OMC as a precursor, combined with an NaOH etching process, in which crystal Si/amorphous SiO2 nanoparticles were encapsulated into the OMC matrix. Not only can such unique porous crystal Si/amorphous SiO2 nanoparticles uniformly dispersed in the OMC matrix mitigate the volume change of active materials during the cycling process, but they can also improve electrical conductivity of Si/SiO2 and facilitate the Li+/Na+ diffusion. When applied as an anode for lithium‐ion batteries (LIBs), the Si/SiO2–OMC composite displayed superior reversible capacity (958 mA h g−1 at 0.2 A g−1 after 100 cycles) and good cycling life (retaining a capacity of 459 mA h g−1 at 2 A g−1 after 1000 cycles). For sodium‐ion batteries (SIBs), the composite maintained a high capacity of 423 mA h g−1 after 100 cycles at 0.05 A g−1 and an extremely stable reversible capacity of 190 mA h g−1 was retained even after 500 cycles at 1 A g−1. This performance is one of the best long‐term cycling properties of Si‐based SIB anode materials. The Si/SiO2–OMC composites exhibited great potential as an alternative material for both lithium‐ and sodium‐ion battery anodes.
Cobalt‐Catalyzed Enantioselective Negishi Cross‐Coupling of Racemic α‐Bromo Esters with Arylzincs
Authors: Liu Feipeng , Zhong Jiangchun , Zhou Yun , Gao Zidong , Walsh Patrick J. , Wang Xueyang , Ma Sijie , Hou Shicong , Liu Shangzhong , Wang Minan , Wang Min , Bian Qinghua
Published: December 2017

The first cobalt‐catalyzed enantioselective Negishi cross‐coupling reaction, and the first arylation of α‐halo esters with arylzinc halides, are disclosed. Employing a cobalt‐bisoxazoline catalyst, various α‐arylalkanoic esters were synthesized in excellent enantioselectivities and yields (up to 97 % ee and 98 % yield). A diverse range of functional groups, including ether, halide, thioether, silyl, amine, ester, acetal, amide, olefin and heteroaromatics is tolerated by this method. This method was suitable for gram‐scale reactions, enabling the synthesis of (R)‐xanthorrhizol with high enantiopurity. Radical clock experiments support the intermediacy of radicals.
Methane gas hydrate kinetics with mixtures of sodium dodecyl sulphate and tetrabutylammonium bromide
Authors: Renault‐Crispo Jean‐Sébastien , Servio Phillip
Published: December 2017

The effect of combining a thermodynamic promoter, tetrabutylammonium bromide (TBAB), with a kinetic promoter, sodium dodecyl sulphate (SDS), to a methane clathrate system was investigated. Kinetic growth experiments were conducted in a semi‐batch stirred tank crystallizer at driving forces of 1500 kPa using a range of 100 to 1500 ppm SDS and 200 to 200 000 ppm TBAB. Solutions containing low concentrations of TBAB in water reduced methane hydrate growth rates up to 55 % for 1250 ppm TBAB compared to pure water. Solutions containing 900 ppm SDS in water enhanced the growth rate by 880 % compared to pure water. Solutions were then tested combining both promoters. The gradual addition of SDS from concentrations between 100 to 1250 ppm to low‐concentration TBAB systems between 200 to 1250 ppm was initially found to reduce growth kinetics, but eventually increased the growth rates once a threshold SDS concentration was reached. In all cases, the promoting effect of the SDS was more pronounced in the absence of the TBAB. The growth kinetics of systems containing 5 and 20 wt% TBAB also followed a similar inhibition‐promotion trend with the SDS concentration. An increase of 177 % in the gas consumption rate was observed when 1500 ppm SDS was added to the 20 wt% TBAB clathrate system. This work demonstrates that SDS can be added to a TBAB‐water‐methane system to enhance gas consumption rates, but care must be taken to ensure that the concentration of the additives places the system in a promotion regime.
Selective Electrogenerative Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Furandialdehyde
Authors: Cao Tao , Wu Mengjia , Ordomsky Vitaly V. , Xin Xi , Wang Hao , Métivier Pascal , Pera‐Titus Marc
Published: December 2017

2,5‐furandialdehyde (DFF) was synthesized by electrogenerative oxidation of 5‐hydroxymethylfurfural (HMF) over a PtRu catalyst with 89 % selectivity at 50 °C after 17 h. This approach opens an avenue for a selective, energy‐efficient and green oxidation of biomass‐derived platform alcohols to added‐value chemicals.