bluuebunny/crossref_metadata_2025 huggingface dataset:
Why Should Lifelong Education Be Considered a Good for All Humanity? Revisiting UNESCO’s View Through Comenius’ Lens
Authors: Kopecký Martin
Published: June 2020

The article contributes to a vigorous debate on the significance of lifelong education and learning held at the political, practical and academic levels, especially concerning approaches of international organizations ( UNESCO in this case). It represents one of the attempts to restore the thoughts of the philosopher, which may serve as valuable sources of inspiration at the time of transitions and crises of a globalized world. The author’s explicit orientation is on ideas that have long been embraced by UNESCO’s education policy. He views them through a lens that is significantly influenced by Comenius. His philosophy is presented as a strong argument to affirm as well as a reason to partially revisit UNESCO’s position. The article builds on a combination of theoretical inquiry and critical analysis of policy documents. In his work, Comenius formulated key and timeless arguments in favour of a universal approach to education throughout the human lifespan, and he also justified why education is a prerequisite for the ability to act rightly and correct what is wrong. Comenius emphasised the ability “to understand right, to act rightly” as dependent on wisdom, and universal education as a pathway to the wisdom. Consequently, according to Comenius, universalism is bound to appreciate such forms of education that in basic features correspond to the ideal of Bildung. It is argued that what UNESCO refers to as universalism is not genuine universalism because it does not fully appreciate education as a source of inner cultivation – one of the prerequisites of acting rightly.
Teaching Using ICT in an International Perspective: Towards Modern Pedagogy
Authors: Zounek Jiří , Záleská Klára , Juhaňák Libor
Published: June 2020

Digital technologies have become an essential part of the education policy in most European countries. ICT implementation into teaching and learning entails considerable potential to encourage or trigger changes in the field of education, particularly in the work of teachers, which leads to thinking about the so-called modern pedagogy. The aim of the study is, therefore, to explore and explain how ICT-related topics are formulated in the education policy of three European countries. Another goal is to describe how Czech, Slovak and Polish teachers use and perceive digital technologies in their work. We use analysis of educational policy documents of selected countries and analysis of three international comparative surveys as well. It is possible to say that in the educational policy of the three countries there is a visible deviation from the traits of traditional pedagogy, with an emphasis on the development of the skills component of learning, in particular on key competences. The teachers themselves are on an imaginary path from traditional to modern pedagogy, in which the possibilities of digital technologies would be used more and more efficiently. It should be teaching, that is more focused on pupils’ active participation, and learning not confined to classroom space.
Numerical Analysis on the Effect of Wavy Partitions on Natural Convection in Porous Enclosure
Authors: Chordiya Jayesh Subhash , Sharma Ram Vinoy
Published: June 2020

The influence of partitions on natural convection in a differentially heated porous enclosure has been investigated for three different partition shapes, namely, sine-wave, corrugated and square-wave shape. The objective is to identify the best partition shape with regard to achieve maximum reduction in the rate of convection heat transfer. Darcy flow model has been used to describe flow in porous media. Coordinate transformation has been used to formulate the governing equations for sine-wave partition owing to its wavy nature. To assess the effectiveness of various partition shapes, the results are compared with porous enclosure without partition and with straight partition. The governing equations are solved using the successive accelerated replacement scheme for a wide range of parameters like partition amplitude, position, Rayleigh number, enclosure aspect ratio (AR), and inclination angle. One of the findings reveals that for the same amplitude and position, the square-wave partition yields the maximum suppression in the value of Nusselt number.
The Thermal Load and Ablation Mechanism of Piston Subjected to Detonation
Authors: Gao Jian , Yao Anren , Yao Chunde
Published: June 2020

The piston in reciprocating engine would be badly ablated under severe knock. However, the mechanism of the detonation-induced thermal ablation of piston is still unclear. A detonation bomb device (DBD) was used to measure the thermal load of piston under detonation. A test specimen mounted on the detonation bomb acts as a piston to bear the detonation load. Transient thermal numerical analysis was performed using the finite element method. Temperature of the specimen and in-cylinder pressure were collected synchronously. A method for estimating wall heat flux under detonation was proposed. Results showed that the heat received by the specimen accounts for about 20.9% of the total heat released by the mixture in this research. Under continuous detonations, the heat of the surface layer could not be conducted to the interior in a short time, leading to a rapid rise in surface temperature. The overall temperature rise of the specimen limits the heat dissipation of the specimen surface layer, resulting in the specimen being ablated by the over-temperature and over-pressure. Piston thermal ablation by detonation is verified and reappeared in the detonation bomb. The thermal load of the piston is largest under theoretical equivalent ratio.
A Simple Immersed Boundary Method for Modeling Forced Convection Heat Transfer
Authors: Yao Guangfa
Published: June 2020

As nonbody-conforming numerical methods using simple Cartesian mesh, immersed boundary methods have become increasingly popular in modeling fluid–solid interaction. They usually do this by adding a body force term in the momentum equation. The magnitude and direction of this body force ensure that the boundary condition on the solid–fluid interface are satisfied without invoking complicated body-conforming numerical methods to impose the boundary condition. A similar path has been followed to model forced convection heat transfer by adding a source term in the energy equation. The added source term will ensure that thermal boundary conditions on the solid–fluid interface are imposed without invoking a boundary conforming mesh. These approaches were developed to handle the Dirichlet boundary condition (constant wall temperature). Few of them deal with the Neumann boundary condition (constant wall heat flux). This paper presents a simple new immersed boundary method. It can deal with the Dirichlet boundary condition, Neumann boundary condition, and conjugated heat transfer by adding an energy source or sink term in the energy conservation equation. The presented approach is validated against the analytical solutions and a very good match is achieved.
Thermohydraulic Behavior of the Liquid–Vapor Flow in the Receiver Tube of a Solar Parabolic Trough Collector
Authors: Sallam Sara , Taqi Mohamed
Published: June 2020

Liquid–vapor flows are present in many industrial applications. In particular, in the solar field, these flows are encountered in the new generations of solar parabolic trough collectors with direct steam generation (PTCs-DSG). In this technical brief, we compare the two-phase convective transfer and the pressure drop models in the PTC-DSG. The results show that the heat exchange coefficients estimated by Chen–Cooper, Shah, Gungor–Winterton, and Kandlikar models have same trend with difference between them. However, the models of Liu–Winterton and Steiner–Taborek seem inappropriate due to the decrease in the exchange coefficient for moderate and high steam qualities. In addition, a comparison of the models describing pressure drops with experimental data of literature was carried out. The results show that the pressure decreases as the steam quality increases and the differences between these models remain small. Friedel's model is the closest to the experiment for high inlet pressures and flow rates, while Chisholm's model gives the best prediction of the pressure drop for low inlet conditions. Effect analysis of inlet conditions shows that the increase in inlet water mass flow and decrease in pressure favor convective heat transfer. The variation of heat flux on tube wall does not affect the convective boiling heat coefficient evaluated by the Chen–Copper model, whereas it influences the calculating coefficient by Gungor–Winterton model for high heat flux and particularly for low steam qualities. Pressure drops are higher at high flow rates and low pressures.
The Discrete Green's Function for Convective Heat Transfer—Part 1: Definition and Physical Understanding
Authors: Eaton John K.
Published: June 2020

The discrete Green's function (DGF) is a superposition-based descriptor of the relationship between the surface temperature and the convective heat transfer from a surface. The surface is discretized into a finite number of elements and the DGF matrix elements relate the heat transfer out of any element i to the temperature rise on every element j of the surface. For a given flow situation, the DGF is insensitive to the thermal boundary condition so it allows direct calculation of the heat transfer for any temperature distribution and noniterative solution of conjugate heat transfer problems. The diagonal elements of the matrix are determined solely by the local velocity field while the off-diagonals are determined by the spread of the thermal wake downstream of a heated element. An analytical DGF for the laminar flat-plate boundary layers is included as an example.
Potent neutralizing antibodies from COVID-19 patients define multiple targets of vulnerability
Authors: Brouwer Philip J. M. , Caniels Tom G. , van der Straten Karlijn , Snitselaar Jonne L. , Aldon Yoann , Bangaru Sandhya , Torres Jonathan L. , Okba Nisreen M. A. , Claireaux Mathieu , Kerster Gius , Bentlage Arthur E. H. , van Haaren Marlies M. , Guerra Denise , Burger Judith A. , Schermer Edith E. , Verheul Kirsten D. , van der Velde Niels , van der Kooi Alex , van Schooten Jelle , van Breemen Mariëlle J. , Bijl Tom P. L. , Sliepen Kwinten , Aartse Aafke , Derking Ronald , Bontjer Ilja , Kootstra Neeltje A. , Wiersinga W. Joost , Vidarsson Gestur , Haagmans Bart L. , Ward Andrew B. , de Bree Godelieve J. , Sanders Rogier W. , van Gils Marit J.
Published: June 2020

Sites of vulnerability in SARS-CoV-2

Antibodies that neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be an important tool in treating coronavirus disease 2019 (COVID-19). Brouwer
et al.
isolated 403 monoclonal antibodies from three convalescent COVID-19 patients. They show that the patients had strong immune responses against the viral spike protein, a complex that binds to receptors on the host cell. A subset of antibodies was able to neutralize the virus. Competition and electron microscopy studies showed that these antibodies target diverse epitopes on the spike, with the two most potent targeting the domain that binds the host receptor.

Science
, this issue p.
643
Novel Aminoglycoside-Tolerant Phoenix Colony Variants of Pseudomonas aeruginosa
Authors: Sindeldecker Devin , Moore Kelly , Li Anthony , Wozniak Daniel J. , Anderson Matthew , Dusane Devendra H. , Stoodley Paul
Published: June 2020

Pseudomonas aeruginosa
is an opportunistic bacterial pathogen and is known to produce biofilms. We previously showed the emergence of colony variants in the presence of tobramycin-loaded calcium sulfate beads. In this study, we characterized the variant colonies, which survived the antibiotic treatment, and identified three distinct phenotypes—classically resistant colonies, viable but nonculturable colonies (VBNC), and phoenix colonies. Phoenix colonies, described here for the first time, grow out of the zone of clearance of antibiotic-loaded beads from lawn biofilms while there are still very high concentrations of antibiotic present, suggesting an antibiotic-resistant phenotype.
Biophysical Properties of Escherichia coli Cytoplasm in Stationary Phase by Superresolution Fluorescence Microscopy
Authors: Zhu Yanyu , Mustafi Mainak , Weisshaar James C.
Published: June 2020

Bacteria in nature usually lack sufficient nutrients to enable growth and replication. Such starved bacteria adapt into a quiescent state known as the stationary phase. The chromosomal DNA is protected against oxidative damage, and ribosomes are stored in a dimeric structure impervious to digestion. Stationary-phase bacteria can recover and grow quickly when better nutrient conditions arise. The biochemistry of stationary-phase
E. coli
is reasonably well understood. Here, we present results from a study of the biophysical state of starved
E. coli
. Superresolution fluorescence microscopy enables high-resolution location and tracking of a DNA locus and of single copies of RNA polymerase (the transcription machine) and ribosomes (the translation machine) in intact
E. coli
cells maintained in stationary phase. Evidently, the chromosomal DNA remains sufficiently permeable to enable transcription and translation to occur. This description contrasts with the usual picture of a rigid stationary-phase cytoplasm with highly condensed DNA.
Prions from Sporadic Creutzfeldt-Jakob Disease Patients Propagate as Strain Mixtures
Authors: Cassard Hervé , Huor Alvina , Espinosa Juan-Carlos , Douet Jean-Yves , Lugan Severine , Aron Naima , Vilette Didier , Delisle Marie-Bernadette , Marín-Moreno Alba , Peran Patrice , Beringue Vincent , Torres Juan Maria , Ironside James W. , Andreoletti Olivier
Published: June 2020

sCJD occurrence is currently assumed to result from spontaneous and stochastic formation of a misfolded PrP nucleus in the brains of affected patients. This original nucleus then recruits and converts nascent PrP
C
into PrP
Sc
, leading to the propagation of prions in the patient’s brain. Our study demonstrates the coexistence of two prion strains in the brains of a majority of the 23 sCJD patients investigated. The relative proportion of these sCJD strains varied both between patients and between brain areas in a single patient. These findings strongly support the view that the replication of an sCJD prion strain in the brain of a patient can result in the propagation of different prion strain subpopulations. Beyond its conceptual importance for our understanding of prion strain properties and evolution, the sCJD strain mixture phenomenon and its frequency among patients have important implications for the development of therapeutic strategies for prion diseases.
Epstein-Barr Virus LMP1 Promotes Syntenin-1- and Hrs-Induced Extracellular Vesicle Formation for Its Own Secretion To Increase Cell Proliferation and Migration
Authors: Nkosi Dingani , Sun Li , Duke Leanne C. , Patel Nilkumar , Surapaneni Sunil K. , Singh Mandip , Meckes David G.
Published: June 2020

LMP1 is a notable viral protein that contributes to the modification of EV content and tumor microenvironment remodeling. LMP1-modified EVs enhance tumor proliferation, migration, and invasion potential and promote radioresistance. Currently, the mechanisms surrounding LMP1 incorporation into the host EV pathways are not well understood. This study revealed that LMP1 utilizes Hrs, Syntenin-1, and specific components of the ESCRT-III complex for release from the cell, enhancement of EV production, and metastatic properties of cancer cells. These findings begin to unravel the mechanism of LMP1 EV trafficking and may provide new targets to control EBV-associated cancers.
Viral Ecogenomics of Arctic Cryopeg Brine and Sea Ice
Authors: Zhong Zhi-Ping , Rapp Josephine Z. , Wainaina James M. , Solonenko Natalie E. , Maughan Heather , Carpenter Shelly D. , Cooper Zachary S. , Jang Ho Bin , Bolduc Benjamin , Deming Jody W. , Sullivan Matthew B.
Published: June 2020

This study explores viral community structure and function in remote and extreme Arctic environments, including subzero brines within marine layers of permafrost and sea ice, using a modern viral ecogenomics toolkit for the first time. In addition to providing foundational data sets for these climate-threatened habitats, we found evidence that the viruses had habitat specificity, infected dominant microbial hosts, encoded host-derived metabolic genes, and mediated horizontal gene transfer among hosts. These results advance our understanding of the virosphere and how viruses influence extreme ecosystems. More broadly, the evidence that virally mediated gene transfers may be limited by host range in these extreme habitats contributes to a mechanistic understanding of genetic exchange among microbes under stressful conditions in other systems.
Diagnostics of Pulsed Beams of Electrons, Ions, and Atoms (Review)
Authors: Pushkarev A. I. , Prima A. I. , Egorova Yu. I. , Ezhov V. V.
Published: June 2020

A review of methods for diagnosing the most important parameters of pulsed beams of electrons, ions, and accelerated atoms, such as the current density, fluence, total energy per pulse, the energy density distribution over the cross section, the composition of the beam, and its energy spectrum, is presented. The main attention is paid to the methods of diagnostics of beams intended for technological applications with a particle energy of 0.01–1 MeV and an energy density of 0.1–10 J/cm2. This paper contains a description of each diagnostic method, its scope of application, and systematic errors. The thermal imaging diagnostics of the total energy of a particle beam, the energy-density distribution over the cross section, the beam movement in the focal plane in a series of pulses, and the beam divergence during its transport to the target are considered. The time-of-flight diagnostics of ion beams is presented, which allows determining the beam composition, the fluence, and the energy spectrum of each type of ion in a beam of a complex composition (ions with different masses and degrees of ionization). The acoustic (thermoradiation) diagnostics based on the detection of acoustic waves, which are generated by a particle beam in a metal target by a piezoelectric transducer, is described.
Recurrent transient heading disorientation heralding acute posterior cerebral artery (PCA) infarction
Authors: Chee Yong Chuan , Ong Beng Hooi
Published: June 2020

Objective

Heading disorientation is a type of pure topographical disorientation. Reported cases have been very few and its underlying mechanism remains unclear. We report an unusual presentation of a 60-year-old man with recurrent transient heading disorientation heralding an acute posterior cerebral artery infarction.

Design

Case report.

Conclusion

Acquired injury to the right retro-splenial region can result in a specific variant of topographical disorientation known as heading disorientation that may present as an atypical transient ischaemic attack-like symptom heralding acute cerebral infarction.
Characteristics and treatment effectiveness of the nummular headache: a systematic review and analysis of 110 cases
Authors: Patel Urvish K , Saleem Sidra , Anwar Arsalan , Malik Preeti , Chauhan Bindi , Kapoor Ashish , Arumaithurai Kogulavadanan , Kavi Tapan
Published: June 2020

Background/objective

Nummular headache (NH) is a primary headache disorder characterised by intermittent or continuous scalp pain, affecting a small circumscribed area of the scalp. As there are limited data in the literature on NH, we conducted this review to evaluate demographic characteristics and factors associated with complete resolution of the headache, and effectiveness of treatment options.

Methods

We performed a systematic review of cases reported through PubMed database, using Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol and ‘nummular headache’, ‘coin-shaped headache’ and ‘coin-shaped cephalalgia’ keywords. Analysis was performed by using χ2test and Wilcoxon rank-sum test. For individual interventions, the response rate (RR%) of the treatment was calculated.

Results

We analysed a total of 110 NH cases, with median age 47 years and age of pain onset 42 years. Median duration to make correct diagnosis was 18 months after first attack. The median intensity of each attack was 5/10 on verbal rating scale over 4 cm diameter with duration of attack <30 min. Patients with NH had median three attacks per day with frequency of 9.5 days per month. 40 (57.97%) patients had complete resolution of the headache after treatment. Patients with complete resolution were younger, more likely to be female, and were more likely to have diagnosis within year. Patients with complete resolution more likely to have received treatment with onabotulinum toxin A (botulinum toxin type A (BoNT-A)), and gabapentin compared with patients without complete resolution. Most effective interventions were gabapentin (n=34; RR=67.7%), non-steroidal anti-inflammatory drugs (NSAIDs) (n=32; RR=65.6%), BoNT-A (n=12; RR=100%) and tricyclic antidepressant (n=9; RR=44.4%).

Conclusion

Younger patients, female sex and early diagnosis were associated with complete resolution. NSAIDs, gabapentin and BoNT-A were most commonly used medications, with significant RRs.
Carbonate burial dissolution related to faults and fractures in the Triassic Daye Formation of the Huandiqiao Section, Huangshi Area, Hubei, China
Authors: Tang Yu , Zhang Yunfeng , Tang Hongming , Wang Zhenyu , Zhao Jianxin , Yang Xiaochen , Xu Liang
Published: June 2020

Carbonate burial dissolution is generally associated with faults and fractures, accompanied by formation of the fracture–vug system that can provide important reservoir space for oil and gas accumulation. Taking the Lower Triassic Daye Formation in the Huandiqiao Section, Huangshi Area, Middle Yangtze Paraplatform, China, as an example, this study elaborates genetic mechanisms of faults and fractures, features of burial dissolution and cementation, and properties of karst water, accompanied by establishment of a genetic model that illustrates the whole process of burial dissolution and cementation. There are a total of nine reverse faults with dominant northwest dips in the study section. Fractures are selectively developed in hanging walls of the nine faults, with tensile features and dominant north–northeast and north–northwest strikes. Dendritic dissolution and subsequent cementation is prevalent in the hanging wall, while they are rare in the footwall. Most of the cements in the fractures of the hanging walls are calcites, with a fluid inclusion homogenization temperature range of 70∼120 °C, overgrowth bands at the pore edge with different luminous intensities, low contents of Na, Ba, K, and Sr, and high contents of Fe, Mn, and Mg. All these characteristics indicate the karst fluid to originate from calcium-rich formation water with hydrothermal genesis. The formation of the dendritic vug and fracture system is ascribed to the upward migration of hydrothermal fluids along the fault planes and fractures that result in selective dissolution. As the water circulation weakens, CaCO3 is gradually supersaturated in the distal zone with reference to the fault as well as the stagnant and weak-circulation zone, eventually forming a complex vug and fracture system.
Modified gravity with an exponential function of curvature
Authors: Granda L. N.
Published: June 2020

The role of an exponential function of the scalar curvature in the modified gravity is analyzed. Two models are proposed. A toy model that complies with local and cosmological constraints and gives appropriate qualitative description of the cosmic evolution. This model contains a saddle matter-dominant critical point that can evolve towards a late time de Sitter attractor. Initial conditions have been proposed, showing that this toy model has an acceptable matter era and gives an approximate qualitative behavior of cosmic evolution. A second viable model, behaves very close to $$\Lambda $$ΛCDM at early times and can satisfy local and cosmological constraints. It behaves as $$R-2\Lambda $$R-2Λ at $$R\rightarrow \infty $$R→∞ and tends to zero at $$R\rightarrow 0$$R→0, containing flat spacetime solution. The model gives viable cosmological trajectories that, as the first model, connect the matter dominated point with a late time de Sitter attractor. The cosmic evolution of the main density parameters in this model is consistent with current observations with an equation of state very close to $$-1$$-1.
Dynamic Reorganization of the Cortical Functional Brain Network in Affective Processing and Cognitive Reappraisal
Authors: Fang Feng , Potter Thomas , Nguyen Thinh , Zhang Yingchun
Published: June 2020

Emotion and affect play crucial roles in human life that can be disrupted by diseases. Functional brain networks need to dynamically reorganize within short time periods in order to efficiently process and respond to affective stimuli. Documenting these large-scale spatiotemporal dynamics on the same timescale they arise, however, presents a large technical challenge. In this study, the dynamic reorganization of the cortical functional brain network during an affective processing and emotion regulation task is documented using an advanced multi-model electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) technique. Sliding time window correlation and [Formula: see text]-means clustering are employed to explore the functional brain connectivity (FC) dynamics during the unaltered perception of neutral (moderate valence, low arousal) and negative (low valence, high arousal) stimuli and cognitive reappraisal of negative stimuli. Betweenness centralities are computed to identify central hubs within each complex network. Results from 20 healthy subjects indicate that the cortical mechanism for cognitive reappraisal follows a ‘top-down’ pattern that occurs across four brain network states that arise at different time instants (0–170[Formula: see text]ms, 170–370[Formula: see text]ms, 380–620[Formula: see text]ms, and 620–1000[Formula: see text]ms). Specifically, the dorsolateral prefrontal cortex (DLPFC) is identified as a central hub to promote the connectivity structures of various affective states and consequent regulatory efforts. This finding advances our current understanding of the cortical response networks of reappraisal-based emotion regulation by documenting the recruitment process of four functional brain sub-networks, each seemingly associated with different cognitive processes, and reveals the dynamic reorganization of functional brain networks during emotion regulation.
Multiplicity moments using Tsallis statistics in high-energy hadron–nucleus interactions
Authors: Sharma S. , Chaudhary G. , Sandeep K. , Singla A. , Kaur M.
Published: June 2020

The study of higher-order moments of a distribution and its cumulants constitute a sensitive tool to investigate the correlations between the particle produced in high-energy interactions. In our previous work, we have used the Tsallis [Formula: see text] statistics, NBD, Gamma and shifted Gamma distributions to describe the multiplicity distributions in [Formula: see text]-nucleus and [Formula: see text]-nucleus fixed target interactions at various energies ranging from [Formula: see text][Formula: see text]GeV to 800[Formula: see text]GeV. In this study, we have extended our analysis by calculating the moments using the Tsallis model at these fixed target experiment data. By using the Tsallis model, we have also calculated the average charged multiplicity and its dependence on energy. It is found that the average charged multiplicity and moments predicted by the Tsallis statistics are in much agreement with the experimental values and indicates the success of the Tsallis model on data from visual detectors. The study of moments also illustrates that KNO scaling hypothesis holds good at these energies.
Ownership Structure and Tax Avoidance: Evidence from Indian SMEs
Authors: Farooq Omar , Zaher Angie Abdel
Published: June 2020

The paper examines the relationship between ownership concentrations and tax avoidance for small–medium enterprises (SMEs) in India. With a panel dataset built from small- and medium-sized enterprise surveys over the period between 2013 and 2014, we find that SMEs with concentrated ownership have a negative association with tax avoidance. The result is more pronounced for SMEs headquartered in states/provinces with stronger economic and institutional environment. The results also indicate that for any two SMEs with similar levels of ownership concentration, the SME with higher capital needs is more likely to avoid taxes.
Kirchhoff–Schrödinger equations in ℝ2 with critical exponential growth and indefinite potential
Authors: Furtado Marcelo F. , Zanata Henrique R.
Published: June 2020

We prove the existence of ground state solution for the nonlocal problem [Formula: see text] where [Formula: see text] is a Kirchhoff type function, [Formula: see text] may be negative and noncoercive, [Formula: see text] is locally bounded and the function [Formula: see text] has critical exponential growth. We also obtain new results for the classical Schrödinger equation, namely the local case [Formula: see text]. In the proofs, we apply Variational Methods besides a new Trudinger–Moser type inequality.
Averaging principle for impulsive stochastic partial differential equations
Authors: Liu Jiankang , Xu Wei , Guo Qin
Published: June 2020

This paper focuses on systems of stochastic partial differential equations with impulse effects. We establish an averaging principle such that the solution to the complex original nonlinear impulsive stochastic evolution equations can be approximated by that to the more simplified averaged stochastic evolution equations without impulses. By adopting stochastic analysis theory, semigroup approach and inequality technique, sufficient conditions are formulated and the mean square convergence is proved. This ensures that we can concentrate on the averaged system instead of the original system, thus providing a solution for reduction of complexity.
Reducing Aerodynamic Noise in a Rod-Airfoil Using Suction and Blowing Control Method
Authors: Abbasi Sarallah , Souri Mohammad
Published: June 2020

This paper aims at investigating a two-dimensional flow over the rod-airfoil as a simple component of an aircraft using URANS equations. The prediction of the flow-induced noise is performed using F-WH analogy. Since Vortex’s periodic production is the main cause of the noise mechanism, by reducing its effect on the airfoil leading edge, the acoustic propagation reduces as well. To control flow and reduce noise, in this study, the suction and blowing active control method is employed (blowing in the rod, and simultaneous suction and blowing in the airfoil). The range of changes in the intensity (I) of the suction and blowing is (0.1U–0.5U), where [Formula: see text] is the rate of free streamflow. The acoustic study showed that the noise is decreased at [Formula: see text] and [Formula: see text] by 55% and 70%, which is due to the suppression and alleviation of vortices. In addition, by using blowing and suction, the lift force is increased and the drag force is decreased, which is aerodynamically favorable. Strouhal number estimation showed that this parameter was reduced by this control method.
Composite Material Based on Carbon Dots and Molecularly Imprinted Polymers: A Facile Probe for Fluorescent Detection of 4-Nitrophenol
Authors: Wang Min , Gao Manjie , Deng Linlin , Kang Xun , Yang Lijuan , Quan Tian , Xia Zhining , Gao Die
Published: June 2020

A new fluorescence composite material for the sensitive and selective determination of 4-nitrophenol (4-NP) was developed based on molecularly imprinted polymers (MIPs) incorporated with carbon dots (CDs). First, fluorescent CDs with a high quantum yield (QY) of 51.8% were prepared by hydrothermal synthesis method by using anhydrous citric acid as carbon source and AEAPMS as surface modifier. Then, CDs were fabricated with MIPs (CDs@MIPs) by sol–gel method using 4-NP as template, (3-aminopropyl) triethoxysilane (APTES) as functional monomer, tetraethoxysilane (TEOS) as cross-linker and CDs as signal sources, respectively. The CDs@MIPs exhibited strong fluorescence property and high selectivity to 4-NP as it incorporated merits of CDs and MIPs. Under optimized conditions, the relative fluorescence intensity of CDs@MIPs decreased linearly with the concentration of 4-NP from 0.025[Formula: see text][Formula: see text]g[Formula: see text]mL[Formula: see text] to 5[Formula: see text][Formula: see text]g[Formula: see text]mL[Formula: see text]. The limit of detection (LOD) of 4-NP was 5[Formula: see text]ng[Formula: see text]mL[Formula: see text] (35[Formula: see text]nM). Specificity and selectivity experiments showed that CDs@MIPs can selectively detect 4-NP with rare interference of other competitive analogs and metal ions. Finally, CDs@MIPs was successfully used to detect 4-NP in river water samples with the recoveries ranging from 94.0% to 103.4%. The results demonstrated that the prepared CDs@MIPs can be applied to the selective and sensitive detection of trace 4-NP in real samples.
Applications of Raman spectroscopy in two-dimensional materials
Authors: Yin Pengkun , Lin Qingyu , Duan Yixiang
Published: June 2020

At present, two-dimensional (2D) materials have shown great application potential in numerous fields based on their physical chemical and electronic properties. Raman spectroscopy and derivative techniques are effective tools for characterizing 2D materials. Raman spectroscopy conveys lots of knowledge on 2D materials, including layer number, doping type, strain and interlayer coupling. This review summarized advanced applications of Raman spectroscopy in 2D materials. The challenges and possible applied directions of Raman spectroscopy to 2D materials are discussed in detail.
A simple sorting algorithm for compositions
Authors: Blecher Aubrey , Brennan Charlotte , Knopfmacher Arnold , Mansour Toufik
Published: June 2020

We provide a particular measure for the degree to which an arbitrary composition deviates from increasing sorted order. The application of such a measure to the transport industry is given in the introduction. In order to obtain this measure, we define a statistic called the number of pushes in an arbitrary composition (which is required to produce sorted order) and obtain a generating function for this. The concept of a push is a geometrical one and leads naturally to several dependant concepts which are investigated. These are the number of cells which do not move in the pushing process and the number of cells that coincide before and after the pushing process (a number not less than those that do not move). The concept of a push leads to combining certain single pushes in a natural way which we define as a frictionless push. A generating function for these is also developed. The underlying geometry of the process also leads naturally to counting the largest first component of arbitrary compositions that are already in a sorted order. We provide a generating function for this.
Geochemical exploration for lithium in NE Iran using the geochemical mapping prospectivity index, staged factor analysis, and a fractal model
Authors: Saadati Hassan , Afzal Peyman , Torshizian Habibollah , Solgi Ali
Published: June 2020

Geochemical exploration for rare metals, specifically lithium, is essential on a regional scale based on their demand and consumption in recent years. The main objective of this study was to delineate lithium anomalies in regional exploration utilizing the geochemical mapping prospectivity index (GMPI), staged factor analysis (SFA), and a concentration-number (C-N) fractal model based on stream sediments. The case study area is 26000 km
2
and is located in the Khorasan Razavi province (NE Iran). In addition, rock samples were used to validate the Li anomalies identified. Results derived via the SFA show that Li was located on a factor denoted as F1-3 with Be, Cs, F, Nb, Sn, Th, U and W, which was used for calculation of the GMPI values. The GMPI data were classified by the C-N fractal method for determination of the Li anomalies. The main anomalies with GMPI ≥ 0.7 and Li ≥ 48 ppm were situated in the SE, SW, north and south parts of the study region. Li grades of rock samples were categorized by the C-N fractal technique for validation of F2-2 anomalies using a log-ratio matrix. The main anomalies were correlated with related lithological units of Li mineralization types. This correlation indicates that the main GMPI–Li anomalies are associated with granitic–pegmatitic units in the central and SE parts, and overlap with clay minerals in the northern and southern sectors of this region. There is good potential for Li mineralization as demonstrated by this hybrid method.
Dynamic calibration of the Shaikan Jurassic full-field fractured reservoir model through single-well DST and multi-well interference discrete fracture network simulation
Authors: Price Neil , LaPointe Paul , Parmassar Kevin , Shi Chunmei , Diamond Phil , Finnila Aleta , Jensen Ole Krogh
Published: June 2020

The hydraulic behaviour of the fractures in a fractured carbonate reservoir is a function of fracture intensity, aperture, intrinsic permeability, length, height and orientation, all of which influence the scale of connectivity and ultimately storage, productivity and reserves. If a geologically realistic fracture model is not appropriately incorporated into upscaled fracture properties for a dynamic simulation, it may still be possible to match a short production history, but calculations of field-wide fracture pore volumes and forecasts of future reservoir development may be poor and uncertain. To accurately represent the fractures, discrete fracture network (DFN) models were built and used to constrain fracture geometries and their hydraulic properties for use in forecasting, field development options and uncertainty characterization. The workflow illustrated in this paper shows how a DFN may be validated and calibrated through the simulation of transient bottom hole pressures from individual drill stem tests and pressure interference data, followed by upscaling to a full-field dynamic simulation model. This DFN-to-simulation workflow, applicable to most conventional fractured reservoirs, successfully matched reservoir pressure history for the field as a whole and for individual wells without having to locally modify any of the upscaled fracture properties around the wells. Sensitivity analysis identified key fracture drivers having the greatest impact upon the history match, and these were combined to produce history matched Low and High Case models. Production forecasts for the Low, Base and High Cases were used to predict reserves, manage risk and optimize the field development plan.

Supplementary material
: Supplementary figures are available at
https://doi.org/10.6084/m9.figshare.c.5001203

Thematic collection:
This article is part of the The Geology of Fractured Reservoirs collection available at:
https://www.lyellcollection.org/cc/the-geology-of-fractured-reservoirs
Keep the Phone in Your Pocket
Authors: Liu Guanhong , Gu Yizheng , Yin Yiwen , Yu Chun , Wang Yuntao , Mi Haipeng , Shi Yuanchun
Published: June 2020

Previous studies have shown that visually impaired users face a unique set of pain points in smartphone interaction including locating and removing the phone from a pocket, two-handed interaction while holding a cane, and keeping personal data private in a public setting. In this paper, we present a ring-based input interaction that enables in-pocket smartphone operation. By wearing a ring with an Inertial Measurement Unit on the index finger, users can perform gestures on any surface (e.g., tables, thighs) using subtle, one-handed gestures and receive auditory feedback via earphones. We conducted participatory studies to obtain a set of versatile commands and corresponding gestures. We subsequently trained an SVM model to recognize these gestures and achieved a mean accuracy of 95.5% on 15 classifications. Evaluation results showed that our ring interaction is more efficient than some baseline phone interactions and is easy, private, and fun to use.
Extraction and Interpretation of Deep Autoencoder-based Temporal Features from Wearables for Forecasting Personalized Mood, Health, and Stress
Authors: Li Boning , Sano Akane
Published: June 2020

Continuous wearable sensor data in high resolution contain physiological and behavioral information that can be utilized to predict human health and wellbeing, establishing the foundation for developing early warning systems to eventually improve human health and wellbeing. We propose a deep neural network framework, the Locally Connected Long Short-Term Memory Denoising AutoEncoder (LC-LSTM-DAE), to automatically extract features from passively collected raw sensor data and perform personalized prediction of self-reported mood, health, and stress scores with high precision. We enabled personalized learning of features by finetuning the general representation model with participant-specific data. The framework was evaluated using wearable sensor data and wellbeing labels collected from college students (total 6391 days from N=239). Sensor data include skin temperature, skin conductance, and acceleration; wellbeing labels include self-reported mood, health and stress scored 0 - 100. Compared to the prediction performance based on hand-crafted features, the proposed framework achieved higher precision with a smaller number of features. We also provide statistical interpretation and visual explanation to the automatically learned features and the prediction models. Our results show the possibility of predicting self-reported mood, health, and stress accurately using an interpretable deep learning framework, ultimately for developing real-time health and wellbeing monitoring and intervention systems that can benefit various populations.
Exploring LoRa for Long-range Through-wall Sensing
Authors: Zhang Fusang , Chang Zhaoxin , Niu Kai , Xiong Jie , Jin Beihong , Lv Qin , Zhang Daqing
Published: June 2020

Wireless signals have been extensively utilized for contactless sensing in the past few years. Due to the intrinsic nature of employing the weak target-reflected signal for sensing, the sensing range is limited. For instance, WiFi and RFID can achieve 3-6 meter sensing range while acoustic-based sensing is limited to less than one meter. In this work, we identify exciting sensing opportunities with LoRa, which is the new long-range communication technology designed for IoT communication. We explore the sensing capability of LoRa, both theoretically and experimentally. We develop the sensing model to characterize the relationship between target movement and signal variation, and propose novel techniques to increase LoRa sensing range to over 25 meters for human respiration sensing. We further build a prototype system which is capable of sensing both coarse-grained and fine-grained human activities. Experimental results show that (1) human respiration can still be sensed when the target is 25 meters away from the LoRa devices, and 15 meters away with a wall in between; and (2) human walking (both displacement and direction) can be tracked accurately even when the target is 30 meters away from the LoRa transceiver pair.
When Sharing Economy Meets IoT
Authors: Wu Di , Xiao Tao , Liao Xuewen , Luo Jie , Wu Chao , Zhang Shigeng , Li Yong , Guo Yike
Published: June 2020

Air pollution is a serious global issue impacting public health and social economy. In particular, exposure to small particulate matter of 2.5 microns or less in diameter (PM2.5) can cause cardiovascular and respiratory diseases, and cancer. Fine-grained urban air quality monitoring is crucial yet difficult to achieve. In this paper, we present the design, implementation, and evaluation of an ambient environment aware system, namely UbiAir, which can support fine-grained urban air quality monitoring through mobile crowdsensing on a bike-sharing system. We have built specific IoT box configured with multiple pollutant sensors and attached on shared bikes to sample micro-scale air quality data in the monitoring space that is split by a scalable grid structure. Both hardware and software data calibration methods are exploited in UbiAir to make the sampled data reliable. Then, we use Bayesian compressive sensing (BCS) as an inference model that leverages the calibrated samples to recover data points without direct measurements and reconstruct an accurate air quality map covering the entire monitoring space. In addition, red envelope based incentive schemes and differential rewarding strategies have been designed in UbiAir, and an adaptive BCS algorithm is proposed to deploy the red envelopes at the most informative positions to facilitate data sampling and inference. We have tested our system on campus with over 100k data measurements collected by 36 students through 18 days. Our real-world experiments show that UbiAir is a light-weight, low-cost, accurate and scalable system for fine-grained air quality monitoring, as compared with other solutions.
Making It Personal
Authors: Parmar Dhaval , Bickmore Timothy
Published: June 2020

Public-speaking situations such as classroom lectures, seminars, and meetings, where speakers must actively engage the audience, require considerable effort from the speaker in gathering verbal and non-verbal feedback from the audience. Garnering feedback can be made easier by technologies such as augmented reality (AR) capable of displaying information in 3D space surrounding the speaker. We present an AR-enabled presentation display system to provide real-time feedback from the audience to the speaker during a presentation. The feedback includes names and affective states of the audience, icons requesting a change in volume and rate of speech, and annotated questions and comments. The design of the feedback system was informed by findings from an exploratory study with academic professionals experienced in delivering presentations. In a between-subjects study, we evaluated presentations displaying feedback information spatially overlaid above the heads of the audience members in one condition and in the periphery of the presenter's view in another condition, as compared with a no-AR control condition. Results showed that the presenters in the overlay condition called upon the audience by name significantly more often than in the peripheral and the control conditions, and they rated the overlay condition as more reliable, helpful, and wanting to use it for future presentations compared to the peripheral condition. Overall, AR feedback was considered useful by both the presenters and the audience and did not negatively impact speaker confidence and state anxiety of the presenter.
Reflow Soldering-Resistant Solid-State 3D Micro-Supercapacitors Based on Ionogel Electrolyte for Powering the Internet of Things
Authors: Asbani B. , Bounor B. , Robert K. , Douard C. , Athouël L. , Lethien C. , Le Bideau J. , Brousse T.
Published: June 2020

The fabrication of all solid-state 3D micro-supercapacitor is challenging for powering connected and miniaturized emerging electronics devices in the frame of the future Internet of Things paradigm. Here we highlight the design of a specific solid electrolyte based on ethylmethylimidazolium bis(trifluoromethanesulfonate)imide confined within polyvinylidenefluoride which enables to meet the requirements of safety, easy packaging, and leakage free 3D micro-supercapacitors. This ionogel-based microdevice (2 mm × 2 mm footprint area) exhibits good cycling stability over 30 000 cycles with an areal energy density of 4.4 μWh.cm−2 and a power density of 3.8 mW.cm−2. It can also sustain the high temperature reflow soldering process (∼250 °C–5 min) without damage, which is performed to directly bond surface mounted miniaturized devices onto printed circuit boards. This strategy not only provides a reference for the design of high-performance 3D interdigitated micro-supercapacitors, but also paves the way to their further implementation in miniaturized electronic chips for Internet of Things applications.