bluuebunny/crossref_metadata_2025 huggingface dataset:
Partial volume mapping using magnetic resonance fingerprinting
Authors: Deshmane Anagha , McGivney Debra F. , Ma Dan , Jiang Yun , Badve Chaitra , Gulani Vikas , Seiberlich Nicole , Griswold Mark A.
Published: March 2019

Magnetic resonance fingerprinting (MRF) is a quantitative imaging technique that maps multiple tissue properties through pseudorandom signal excitation and dictionary‐based reconstruction.

The aim of this study is to estimate and validate partial volumes from MRF signal evolutions (PV‐MRF), and to characterize possible sources of error.

Partial volume model inversion (pseudoinverse) and dictionary‐matching approaches to calculate brain tissue fractions (cerebrospinal fluid, gray matter, white matter) were compared in a numerical phantom and seven healthy subjects scanned at 3 T. Results were validated by comparison with ground truth in simulations and ROI analysis in vivo. Simulations investigated tissue fraction errors arising from noise, undersampling artifacts, and model errors. An expanded partial volume model was investigated in a brain tumor patient.

PV‐MRF with dictionary matching is robust to noise, and estimated tissue fractions are sensitive to model errors. A 6% error in pure tissue T1 resulted in average absolute tissue fraction error of 4% or less. A partial volume model within these accuracy limits could be semi‐automatically constructed in vivo using k‐means clustering of MRF‐mapped relaxation times. Dictionary‐based PV‐MRF robustly identifies pure white matter, gray matter and cerebrospinal fluid, and partial volumes in subcortical structures. PV‐MRF could also estimate partial volumes of solid tumor and peritumoral edema.

We conclude that PV‐MRF can attribute subtle changes in relaxation times to altered tissue composition, allowing for quantification of specific tissues which occupy a fraction of a voxel.
Cyclic poly(lactide)s via the ROPPOC method catalyzed by alkyl‐ or aryltin chlorides
Authors: Kricheldorf Hans R. , Weidner Steffen M. , Scheliga Felix
Published: March 2019

A comparison of tributyltin chloride, dibutyltin dichloride, and butyltin trichloride as catalysts of ring‐opening polymerizations (ROPs) of l‐lactides at 160 °C in bulk reveals increasing reactivity in the above order, but only the least reactive catalysts, Bu3SnCl, yield a uniform reaction product, namely cyclic poly(L‐lactide)s with weight average molecular weights (Mw's) in the range of 40,000–80,000. A comparison of dimethyltin , dibutyltin , and diphenyltin dichlorides resulted in the following order of reactivity: Me2SnCl2 < Bu2SnCl2 < <Ph2SnCl2. In this series also, the most reactive catalyst yields cyclic polylactides, but the extent of cyclization varies with the molecular weight. The formation of cyclic polylactides is explained by ROP combined with simultaneous polycondensation involving end‐to‐end cyclization (ROPPOC method). ROP of meso‐lactide at 80 or 60 °C yields even‐numbered linear chains as main products, a result supporting the ROPPOC mechanism. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 952–960
Electrical Properties of Vertical p‐NiO/n‐Ga2O3 and p‐ZnCo2O4/n‐Ga2O3 pn‐Heterodiodes
Authors: Schlupp Peter , Splith Daniel , von Wenckstern Holger , Grundmann Marius
Published: March 2019

Vertical β‐Ga2O3‐based pn‐heterostructures are investigated by current–voltage measurements and thermal admittance spectroscopy. The β‐Ga2O3 thin films are grown by pulsed laser deposition (PLD) on (00.1)ZnO:Ga/(11.0)Al2O3 substrates at 670 °C. Two different p‐type oxides are used to fabricate pn‐heterodiodes which are investigated with respect to rectification, temperature stability, and breakdown behavior. For that, p‐NiO and p‐ZnCo2O4 are grown by PLD at room temperature on top of a β‐Ga2O3 thin film, respectively. The rectification ratio at room temperature is about nine orders of magnitude, the ideality factor is about 2 and the on‐resistance is below 1 Ω cm2. Both diode types did not show degradation for temperatures up to 100 °C. Thermal admittance spectroscopy revealed defects in β‐Ga2O3 with thermal activation energy Ea of about 200 meV for both diode types. Additionally, a level with Ea ≈ 240 meV is detected for the NiO/Ga2O3 diodes only. In general, both diode types are suited to realize pn‐heterodiodes with high rectification, but NiO is especially interesting for defect characterization by deep‐level optical spectroscopy due to its transparency up to about 3.7 eV.
Temperature‐Dependent Raman Study of Nanostructured and Multifunctional Materials
Authors: Šćepanović Maja , Grujić‐Brojčin Mirjana , Lazarević Nenad , Popović Zoran V.
Published: March 2019

The scope of this paper is temperature dependence of Raman spectra in several nanocrystalline materials and iron‐based single‐crystals. The Raman results presented and analyzed here are related to TiO2 nanopowders (with dominant anatase and brookite phase) and ZnxCd1−xSe single layers measured at different temperatures. Temperature‐dependent Raman spectra of iron‐based sulphides and selenides (BaFe2S3 and BaFe2Se3), as well as alkali‐doped iron selenides (KxFe2−ySe2 and K0.8Fe1.8Co0.2Se2) are also analyzed. A physical model, including thermal expansion as well as three‐ and four‐phonon anharmonic effects, is used to quantitatively analyze temperature evolution of the characteristic Raman mode self‐energies for the materials of interest. It is demonstrated how this model can be used as a tool for predicting the temperature of structural and phase transitions, with critical scrutany of its limitations.
Interstitial Li+ Controls the UV Transmission and the Radiation Hardness in YAG
Authors: Derdzyan Marina V. , Hovhannesyan Karine L. , Novikov Artur , Auffray Etiennette , Petrosyan Ashot G. , Dujardin Christophe
Published: March 2019

Optical absorption spectra measured in as‐grown and gamma‐ray irradiated un‐doped YAG, Li‐doped YAG, and Ca‐doped YAG single crystals are compared for characterization of effects introduced by impurities. The studies are conducted on single crystals grown by the vertical Bridgman method. Basing on the Li+ incorporation mechanism, clarification is done regarding the optimal amounts of Li+ for preparation of YAG:Li crystals with low concentration of anion vacancies and related defects giving rise to absorption in the UV range. Differences in behavior are recorded in variously doped crystals subjected to gamma‐ray irradiation; in comparison to un‐doped YAG, the induced absorption coefficient in Li‐doped YAG of optimal composition is lower more than six times. High transmission in the UV and high radiation tolerance are important for most applications of YAG, especially when operated in high radiation fields.
A nanoparticle co‐matrix for multiple charging in matrix‐assisted laser desorption ionization imaging of tissue
Authors: Banstola Bijay , Murray Kermit K.
Published: March 2019

Rationale

A two‐component matrix of 2‐nitrophloroglucinol (2‐NPG) and silica nanoparticles was used for matrix‐assisted laser desorption ionization (MALDI) mass spectrometry imaging of high‐charge‐state biomolecules in tissue. Potential advantages include increased effective mass range and efficiency of fragmentation.

Methods

A mixture of 2‐NPG matrix and silica nanoparticles was applied to cyrosectioned 10 μm thick mouse brain tissue. The mixture was pipetted onto the tissue for profiling and sprayed for tissue imaging. MALDI images were obtained under high vacuum in a commercial time‐of‐flight mass spectrometer.

Results

The combined 2‐NPG and nanoparticle matrix produced highly charged ions from tissue with high‐vacuum MALDI. Nanoparticles of 20, 70, 400, and 1000 nm in diameter were tested, the 20 nm particles producing the highest charge states. Images of mouse brain tissue obtained from highly charged ions show similar spatial localization.

Conclusions

The combined 2‐NPG and nanoparticle matrix produces highly charged ions from tissue through a mechanism that may rely on the high surface area of the particles which can dry the tissue, and their ability to bind analyte molecules thereby assisting in crystal formation and production of multiply charged ions on laser irradiation.
Innovative applications of subgrade biogeochemical reactors: Three case studies
Authors: Gamlin Jeff , Cox Jeremy , Castor Andrew
Published: March 2019

Subgrade biogeochemical reactors (SBGRs) are an in situ remediation technology shown to be effective in treating contaminant source areas and groundwater hot spots, while being sustainable and economical. This technology has been applied for over a decade to treat chlorinated volatile organic compound source areas where groundwater is shallow (e.g., less than approximately 30 feet below ground surface [ft bgs]). However, this article provides three case studies describing innovative SBGR configurations recently developed and tested that are outside of this norm, which enable use of this technology under more challenging site conditions or for treatment of alternative contaminant classes. The first SBGR case study addresses a site with groundwater deeper than 30 ft bgs and limited space for construction, where an SBGR column configuration reduced the maximum trichloroethene (TCE) groundwater concentration from 9,900 micrograms per liter (μg/L) to <1 μg/L (nondetect) within approximately 15 months. The second SBGR is a recirculating trench configuration that is supporting remediation of a 5.7‐acre TCE plume, which has significant surface footprint constraints due to the presence of endangered species habitat. The third SBGR was constructed with a new amendment mixture and reduced groundwater contaminant concentrations in a petroleum hydrocarbon source area by over 97% within approximately 1 year. Additionally, a summary is provided for new SBGR configurations that are planned for treatment of additional classes of contaminants (e.g., hexavalent chromium, 1,4‐dioxane, dissolved explosives constituents, etc.). A discussion is also provided describing research being conducted to further understand and optimize treatment mechanisms within SBGRs, including a recently developed sampling approach called the aquifer matrix probe.
Nuclear magnetic resonance logging: Example applications of an emerging tool for environmental investigations
Authors: Spurlin Matthew S. , Barker Brent W. , Cross Bradley D. , Divine Craig E.
Published: March 2019

Nuclear magnetic resonance (NMR) geophysical tools have been widely used in the petroleum exploration industry since the 1960s and have improved significantly in the last two decades. These tools can provide estimates of bulk porosity and fluid content, quantification of bound versus mobile fluids, and estimates of hydraulic conductivity (K). Although the size and cost of oil‐field tools historically limited their use for near‐surface applications, smaller and more economical downhole NMR logging tools are now available for detecting and characterizing the formation water content and K to support environmental and groundwater resource investigations. These tools can be deployed using direct‐push drilling techniques or they can be lowered into existing open borings or wells with nonconductive polyvinyl chloride casings and screens. In many cases, using the tool in existing wells offers a safer and more cost‐effective alternative compared to drilling new boreholes. For environmental investigations, NMR can provide useful high‐resolution quantitative hydrostratigraphic information that can provide additional valuable data to further inform and refine the conceptual site model. This paper highlights several NMR field investigations that demonstrate the viability of this technology as a site characterization tool for near‐surface investigations. NMR measurements were compared to data from lithologic logs, cone penetrometer testing data, and prior field hydraulic tests. Use of NMR to detect vadose zone water, including previously unidentified perched groundwater zones, provided hydrostratigraphic details that could not be gleaned from historical well drilling logs and were used to evaluate drainable pore water versus pore water bound in small pores by capillary forces or electrochemically clay‐bond water. NMR also produced K estimates similar to those from conventional hydraulic tests, but the improved vertical resolution from NMR provided additional information regarding the vertical heterogeneity of the formation along the entire length of the well or borehole. Additionally, bench‐scale tests are presented that confirm the capability for NMR to reliably detect and quantify light nonaqueous phase liquid saturation (specifically diesel fuel and weathered gasoline) in situ. The field tests combined with bench‐scale testing results affirm the applicability and potential for NMR as a practical characterization tool that should increasingly be utilized in environmental investigations.
In situ chemical oxidation: Lessons learned at multiple sites
Authors: Pac Timothy J. , Baldock James , Brodie Brendan , Byrd Jennifer , Gil Beatriz , Morris Kevin A. , Nelson Denice , Parikh Jaydeep , Santos Paulo , Singer Miguel , Thomas Alan
Published: March 2019

This paper compiles a detailed set of in situ chemical oxidation (ISCO) lessons learned pertaining to design, execution, and safety based on global experiences over the last 20 years. While the benefits of a “correct” application are known (e.g., cost effectiveness, speed, permanence of treatment), history also provides examples of a variety of “incorrect” applications. These provide an opportunity to highlight recurring themes that resulted in failures. ISCO is, and will continue to provide, an important remedial tool for site remediation, particularly as a component of a multifaceted approach for addressing large and complex sites. Future success, however, requires an objective understanding of both the benefits and the limitations of the technology. The ability to learn from the mistakes of the past provides an opportunity to eliminate, or at least minimize, them in the future. Over the last 25 years of ISCO application, process understanding and knowledge have improved and evolved. This paper combines a thorough discussion of lessons learned through decades of ISCO implementation throughout all aspects of ISCO projects with an analysis of changes to the ISCO remediation market. By discussing the interplay of these two themes and providing recommendations from collective lessons learned, we hope to improve the future of safe, cost‐effective, and successful applications of ISCO.
Evaluating the longevity of a PFAS in situ colloidal activated carbon remedy
Authors: Carey Grant R. , McGregor Rick , Pham Anh Le‐Tuan , Sleep Brent , Hakimabadi Seyfollah Gilak
Published: March 2019

The remediation of per‐ and polyfluoroalkyl substances by injection of colloidal activated carbon (CAC) at a contaminated site in Central Canada was evaluated using various visualization and modeling methods. Radial diagrams were used to illustrate spatial and temporal trends in perfluoroalkyl acid (PFAA) concentrations, as well as various redox indicators. To assess the CAC adsorption capacity for perfluorooctane sulfonate (PFOS), laboratory Freundlich isotherms were derived for PFOS mixed with CAC in two solutions: (1) PFOS in a pH 7.5 synthetic water that was buffered by 1 millimolar NaHCO3 (Kf = 142,800 mg1‐a La/kg and a = 0.59); and (2) a groundwater sample (pH = 7.4) containing PFOS among other PFAS from a former fire‐training area in the United States (Kf = 4,900 mg1‐a La/kg and a = 0.24). A mass balance approach was derived to facilitate the numerical modeling of mass redistribution after CAC injection, when mass transitions from a two‐phase system (aqueous and sorbed to organic matter) to a three‐phase system that also includes mass sorbed to CAC. An equilibrium mixing model of mass accumulation over time was developed using a finite‐difference solution and was verified by intermodel comparison for prediction of CAC longevity in the center of a source area. A three‐dimensional reactive transport model (ISR‐MT3DMS) was used to indicate that the CAC remedy implemented at the site is likely to be effective for PFOS remediation for decades. Model results are used to recommend remedial design and monitoring alternatives that account for the uncertainty in long‐term performance predictions.
Edge‐coloring linear hypergraphs with medium‐sized edges
Authors: Faber Vance , Harris David G.
Published: March 2019

Motivated by the Erdos̋‐Faber‐Lovász (EFL) conjecture for hypergraphs, we consider the list edge coloring of linear hypergraphs. We show that if the hyper‐edge sizes are bounded between i and inclusive, then there is a list edge coloring using colors. The dependence on n in the upper bound is optimal (up to the value of Ci,ϵ).
Multifunctional Ternary Nanocomposites of Ni/Polypyrrole/Reduced Graphene Oxide as Supercapacitor and Electrocatalyst in Methanol Oxidation
Authors: Sarkar Chandrama , Nath Jayashree , Bhuyan Shilpa , Dolui Swapan K.
Published: March 2019

In this work the concurrent electrochemical energy storage and conversion characteristics of Ni nanoparticles supported on polypyrrole‐reduced graphene oxide (Ni/PPy/rGO) nanocomposite is reported. Ni/PPy/rGO nanocomposite was synthesized by mixing its precursors PPy/rGO and NiCl2.6H2O, where Ni2+ was reduced to Ni at pH 10.5. The obtained nanocomposite is characterized using FTIR, XRD, Raman Spectroscopy, SEM and dynamic light scattering methods. The electrochemical energy storage properties of the nanocomposite are investigated using cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy tests. Electrochemical analysis reveals that Ni/PPy/rGO nanocomposite has high specific capacitance of 763.49 Fg−1 at 1.31 Ag−1 current density with capacity retention of 96.75% after 200 cycles Ni/PPy/rGO nanocomposite is also used as electrode in methanol electro‐oxidation. Cyclic voltammetry and chronoamperometry are carried out to study the electrochemical energy conversion properties of the composite towards methanol electro‐oxidation. The anodic current density of the Ni/PPy/rGO nanocomposite is much higher than that of Ni/rGO and PPy/rGO. Moreover, the onset potential of Ni/PPy/rGO nanocomposite is much lower than that of Ni/rGO and PPy/rGO. The results show that the Ni/PPy/rGO nanocomposite is electro‐catalytically active and highly stable.
Single and Binary Adsorption of Zn (II) and Cr (VI) Heavy Metals onto Synthesized Silica ‐Based MCM‐41
Authors: Toor Sehaspreet Kaur , Kushwaha Jai Prakash , Sangal Vikas Kumar
Published: March 2019

Effluents from numerous Industries like textile, paint, pharmaceutical, steel and electroplating industries liberate both Zinc [Zn (II)] and Chromium [Cr (VI)] heavy metals. In this work, adsorptive interaction of toxic Zn (II) heavy metal in aqueous solution with synthesized mesoporous silica based MCM‐41 was investigated. Further, the effects of presence of Cr (VI) heavy metal on the adsorption of Zn (II) and vice versa were investigated by simultaneous competitive binary adsorption from Cr (VI) and Zn (II) aqueous binary solution. Batch experiments were executed to see the effects of parameters like pH, adsorbent dose (m), adsorbate concentration and adsorption time (t). Optimum conditions for Zn (II) treatment were obtained as: initial pH (pHi) =7, m=0.1 g/L and t=2 h. Competitive adsorption of both Cr (VI) and Zn (II) from their binary solution was studied at 288− 308 K temperatures. Obtained equilibrium data were then fitted to different competitive multicomponent isotherm models like Langmuir (extended), Freundlich isotherm (extended), Sheindrof‐Rebuhn‐Sheintuch (SRS) isotherm and Redlich‐Peterson isotherm (modified) models, and various isotherm interaction parameters were calculated.
Aza‐Michael Addition of 5‐Substituted Tetrazole Catalysed By a Novel Nanoparticle Solid Base Catalyst Involving a Layered Zinc Hydroxide Supported on a Ferrite Core
Authors: Pazoki Farzane , Mehraban Jamshid Azarnia , Shamsayei Maryam , Bakhshi Bita , Esfandiarpour Razieh , Miraki Maryam Kazemi , Heydari Akbar
Published: March 2019

Fe3O4@SiO2@layered Zinc hydroxide (LZH) (0.85 mol %) efficiently was catalyzed the aza‐Michael reaction of 5‐substituted tetrazoles derivatives with α, β‐unsaturated carbonyl compound under reflux in acetonitrile to produce the new compounds. These new compounds were investigated for antibacterial activity and studied for the structural properties by theoretical calculations.
An Anthracene Excimer Fluorescence Probe on Mesoporous Silica for Dual Functions of Detection and Adsorption of Mercury (II) and Copper (II) with Biological In Vivo Applications
Authors: Chatterjee Sobhan , Gohil Hardipsinh , Raval Ishan , Chatterjee Shruti , Paital Alok Ranjan
Published: March 2019

Dual functional activity by the same organic–inorganic hybrid material toward selective metal ion detection and its adsorption has drawn more attraction in the field of sensing. However, most of the hybrid materials in the literature are either for sensing studies or adsorption studies. In this manuscript, a fluorescent active hybrid material SiO2@PBATPA is synthesized by covalent coupling of anthracene‐based chelating ligand N,N′‐(propane‐1,3‐diyl) bis(N‐(anthracen‐9‐ylmethyl)‐2‐((3‐(triethoxysilyl)propyl) amino) acetamide) (PBATPA) within the mesopores of newly synthesized cubic mesoporous silica. The synthetic strategy is designed to form an exclusively intramolecular excimer on a solid surface, which is then used as a sensory tool for selective detection of metal ions through fluorescence quenching by the destruction of excimer upon metal ion binding. The dual functions of sensing and adsorption studies show selectivity toward Hg2+ and Cu2+ among various metal ions with detection limits of 37 and 6 ppb, respectively, and adsorption capacities of 482 and 246 mg g−1, respectively. This material can be used as a sensory cum adsorbent material in real food samples and living organisms such as the brine shrimp Artemia salina without any toxic effects from the material.
Silica‐Mediated Formation of Nickel Sulfide Nanosheets on CNT Films for Versatile Energy Storage
Authors: Lu Pengyi , Wang Xiaowei , Wen Lei , Jiang Xiaotong , Guo Wenlei , Wang Lei , Yan Xiao , Hou Feng , Liang Ji , Cheng Hui‐Ming , Dou Shi Xue
Published: March 2019

An effective, nondestructive, and universal strategy to homogeneously modify freestanding carbon nanotube (CNT) films with various active species is essential to achieve functional electrodes for flexible electrochemical energy storage, which is challenging and has attracted considerable research interest. In this work, a generalizable concept, to utilize silicon oxide as the intermediate to uniformly decorate various metal sulfide nanostructures throughout CNT films is reported. Taking nickel sulfide nanosheet/CNT (NS/CNT) films, in which the NS nanosheets are homogeneously attached on the intact few‐walled CNTs, as an example, the sheet‐like NS provides sufficient active sites for redox reactions and the CNT network acts as an efficient electron highway, maintaining the structural integrity of the composite and also buffering volume changes. These merits enable NS/CNT films to meet the requirements of versatile energy storage applications. When used for supercapacitors, a high specific capacitance (2699.7 F g−1/10 A g−1), outstanding rate performance at extremely high rates (1527 F g−1/250 A g−1), remarkable cycling stability, and excellent flexibility can be achieved, among the best performance so far. Moreover, it also delivers excellent performance in the storage of Li and Na ions, meaning it is also potentially suitable for Li/Na ion batteries.
A Directional Strain Sensor Based on Anisotropic Microhoneycomb Cellulose Nanofiber‐Carbon Nanotube Hybrid Aerogels Prepared by Unidirectional Freeze Drying
Authors: Wang Cong , Pan Zheng‐Ze , Lv Wei , Liu Bilu , Wei Jie , Lv Xiaohui , Luo Yi , Nishihara Hirotomo , Yang Quan‐Hong
Published: March 2019

Aerogels are one of the most popular composite reinforcement materials because of their high porosity and their continuous and homogeneous network. Most aerogels are isotropic, thus leading to isotropic composites when they are used as fillers. This fundamentally limits their applications in areas where anisotropy is needed. Here, an anisotropic microhoneycomb cellulose nanofiber‐ (CellF)‐carbon nanotube (CNT) aerogel (denoted MCCA) is reported that contains unidirectionally aligned penetrating microchannels, which is prepared by a unidirectional freeze‐drying method, using the structure‐directing function of the CellFs. Due to its anisotropic nature, MCCA‐reinforced polydimethylsilexane (denoted MCCA/PDMS) shows distinct anisotropic behavior, with the electrical conductivity and Young's modulus along the direction of penetrating microchannels being approximately twice those in the orthogonal direction. MCCA/PDMS is used to make “directional” strain sensors with electrical resistance as the output signal. They demonstrate a 92% sensitivity difference between the microchannel direction and its orthogonal direction. This approach can be used to prepare anisotropic MCCA‐based composites with other polymers for different applications.
Tailoring Electronic Properties of SnO2 Quantum Dots via Aluminum Addition for High‐Efficiency Perovskite Solar Cells
Authors: Wang Enqi , Chen Peng , Yin Xingtian , Wu Yutao , Que Wenxiu
Published: March 2019

Owing to its splendid electrical and optical properties, tin oxide (SnO2) has been proven to be an effective electron transport layer (ETL) material for high‐efficiency perovskite solar cells (PSCs). However, the surface coverage, conductivity, and energy loss at the SnO2/perovskite interface still have room for improvement. Herein, a facile method by mixing a SnO2 QD solution with an aluminum (Al) chloride precursor solution at room temperature to achieve the addition of Al into the SnO2 QD (Al: SnO2) precursor is proposed. Based on this strategy, conductivity, electron mobility, and band alignment with the perovskite layer have been significantly improved. Besides, the introduction of Al also increases the coverage of the SnO2 film, consequently contribute to improving the capability to block the charge transfer from FTO to the ETL. Furthermore, fewer defect states are also demonstrated for the perovskite films deposited on Al: SnO2 films than the control samples. With the optimized addition ratio of 5%, the devices exhibit an average efficiency (PCE) of 17.01%, which is superior to that of the control device of 15.80%. The champion device using Al: SnO2 ETL delivers an impressive PCE of 18.20%. This research indicates that the low‐temperature solution‐processed Al: SnO2 is a promising ETL for high‐efficiency PSCs.
Intelligent sentiment analysis approach using edge computing‐based deep learning technique
Authors: Sankar H. , Subramaniyaswamy V. , Vijayakumar V. , Arun Kumar Sangaiah , Logesh R. , Umamakeswari A.
Published: March 2019

Sentiment analysis and opinion mining has become a major tool for collecting information from customer reviews on user sentiments and emotions, especially for online video streaming services and social networks. The increasing use of smartphones has popularized subscription to various streaming services that provide streaming media and video‐on‐demand. These applications offer a gateway to analyze user reviews by introducing sentiment analysis in the mobile environment. Online user reviews can hold a lot of useful information and help predict user interests. Analysis of user reviews can provide substantive information for business processing. Sentiment classification of these reviews is a commonly used analysis technique. Usually, these reviews are given in a text format, with every word in each considered a feature, so selection should focus on optimal features from all available features present in the reviews. This study employs machine learning algorithms to extract the best features from the training review data set. Then, the selected features are fed into the convolutional neural network and other fully connected layers for further processing. The proposed approach is evaluated with the standard evaluation metrics, such as precision, accuracy, recall, and f‐measure, using three distinct benchmark data sets: polarity, Rotten Tomatoes, and IMDb. This work has also employed a pretrained sentiment analysis model over an Android application framework to classify reviews on a Smartphone without the need for any cloud or server‐side API.
Race and Racism in Fraternity and Sorority Life: A Historical Overview
Authors: Gillon Kathleen E. , Beatty Cameron C. , Salinas Cristobal
Published: March 2019

This chapter briefly explores the history of race and racism in fraternity/sorority (F&S) life through the themes of exclusion, racial uplift, and cultural relevance.
The Property Functions of Whiteness Within Fraternity and Sorority Culture and Its Impact on Campus
Authors: Harris Jessica C. , Barone Ryan P. , Finch Hunter
Published: March 2019

In this chapter, the authors outline the property functions of whiteness within fraternity and sorority culture from both a historical and present‐day perspective.
Understanding and Supporting Historically Native American Fraternities and Sororities
Authors: Still Corey M. , Faris Breanna R.
Published: March 2019

In this chapter, the authors provide perspectives and recommendations for student affairs practitioners who work with Native Students and Historically Native American Fraternities and Sororities.
Model‐based protocol specification
Authors: Mordecai Yaniv
Published: March 2019

We propose a holistic Model‐Based Protocol Specification (MBPS) framework. Standards, procedures, and protocols are important anchors for interconnected systems: they facilitate the connectivity of billions of devices around the world, commodify advanced technologies and solutions, and enable efficient services involving trillions of transactions in aviation, medicine, e‐commerce, transportation, infrastructure, and other domains. Domain protocols allow for conventional interactions within a domain among ecosystem entities and humans (eg, airline ticketing, financial transactions, etc). Protocol specifications must be formal, consistent, and verifiable. Nevertheless, most current standard protocols are text‐based, unverifiable, and often inconsistent with themselves and with other standards. Text‐based standards are difficult to manage, track, control, and adopt. MBPS includes three critical enablers: a modeling language, a modeling process, and a model‐supported standardization process. This paper employs Object‐Process Methodology (OPM), a model‐based systems engineering framework, endorsed as ISO‐19450, for modeling and simulation of the generic protocol specification process and for two examples: (a) a Kerberos authentication protocol revision based on a previous Kerberos model and on a recently discovered vulnerability and (b) a domain‐specific Publish—Subscribe protocol application for selective information distribution.
Catalytic Asymmetric Synthesis of Spiropyrazolones and their Application in Medicinal Chemistry
Authors: Xie Xin , Xiang Li , Peng Cheng , Han Bo
Published: March 2019

Chiral spiropyrazolones are unique frameworks widely found in a large family of medicinally relevant compounds with various biological activities. Substantial research efforts have been invested toward stereoselectively by constructing spiro‐cyclic structures. Over the past years, remarkable progress has been made in the organo‐ and metal‐catalyzed asymmetric synthesis of spiropyrazolones through the utilization of accessible simple pyrazolone derivatives as raw materials. This review is organized according to the size of the spiro‐ring fused at the 4‐position of the pyrazolone framework. In the last part, the bio‐evaluations of chiral spiropyrazolones for drug discovery are summarized.
The SMFA program for quantum chemistry calculations on large molecules
Authors: Kobayashi Rika , Addicoat Matthew A. , Gilbert Andrew T.B. , Amos Roger D. , Collins Michael A.
Published: March 2019

SMFA is a general program package for performing quantum chemistry calculations on large molecules, using an energy‐based fragmentation approach. The program can calculate electronic energies, energy gradients and second derivatives; perform geometry optimization; find first order saddle points (transition states); perform energy optimized scans along a user‐defined path; and evaluate various molecular properties. The program can use any of the following quantum chemistry packages: GAMESS(US), GAUSSIAN, NWChem and Q‐Chem. In addition, SMFA provides a number of utility programs that,inter alia, calculate vibrational frequencies and infrared spectra with isotopic substitutions, the electrostatic potential on the solvent‐accessible‐surface, and isodesmic and higher order near‐iso‐energetic reaction schemes. Calculations of the electronic energy and related properties can be carried out using a scheme that provides a computation time that is linearly dependent on the size of the molecule or, if the user has enough processing units available, in a walltime that is independent of the size of the molecule.

This article is categorized under:

Software > Quantum Chemistry

Electronic Structure Theory > Ab Initio Electronic Structure Methods

Structure and Mechanism > Computational Biochemistry and Biophysics
From modelling of systems with constraints to generalized geometry and back to numerics
Authors: Salnikov Vladimir , Hamdouni Aziz
Published: March 2019

In this note we describe how some objects from generalized geometry appear in the qualitative analysis and numerical simulation of mechanical systems. In particular we discuss double vector bundles and Dirac structures. It turns out that those objects can be naturally associated to systems with constraints – we recall the mathematical construction in the context of so called implicit Lagrangian systems. We explain how they can be used to produce new numerical methods, that we call Dirac integrators.

On a test example of a simple pendulum in a gravity field we compare the Dirac integrators with classical explicit and implicit methods, we pay special attention to conservation of constrains. Then, on a more advanced example of the Ziegler‐type system we show that the choice of numerical methods can indeed affect the conclusions of qualitative analysis of the dynamics of mechanical systems. We also tell why we think that Dirac integrators are appropriate for this kind of systems by explaining the relation with the notions of geometric degree of non‐conservativity and kinematic structural stability.
Challenging Methods and Results Obtained from User-Generated Content in Barcelona’s Public Open Spaces
Authors: Pallares-Barbera Montserrat , Masala Elena , Jokovic Jugoslav , Djukic Aleksandra , Albacete Xavier
Published: March 2019

User-generated content (UGC) provides useful resources for academics, technicians and policymakers to obtain and analyse results in order to improve lives of individuals in urban settings. User-generated content comes from people who voluntarily contribute data, information, or media that then appears in a way which can be viewed by others; usually on the Web. However, to date little is known about how complex methodologies for getting results are subject to methodology-formation errors, personal data protection, and reliability of outcomes. Different researches have been approaching to inquire big data methods for a better understanding of social groups for planners and economic needs. In this chapter, through UGC from Tweets of users located in Barcelona, we present different research experiments. Data collection is based on the use of REST API; while analysis and representation of UGC follow different ways of processing and providing a plurality of information. The first objective is to study the results at a different geographical scale, Barcelona’s Metropolitan Area and at two Public Open Spaces (POS) in Barcelona, Enric Granados Street and the area around the Fòrum de les Cultures; during similar days in two periods of time - in January of 2015 and 2017. The second objective is intended to better understand how different types of POS’ Twitter-users draw urban patterns. The Origin-Destination patterns generated illustrate new social behaviours, addressed to multifunctional uses. This chapter aims to be influential in the use of UGC analysis for planning purposes and to increase quality of life.
Social Implications of New Mediated Spaces: The Need for a Rethought Design Approach
Authors: Zammit Antoine , Kenna Therese , Maksymiuk Gabriela
Published: March 2019

Departing from the traditional understanding of the social implications of urban design and the underlying notion of ‘place’, the chapter first questions its current relevance vis-à-vis the mediated city. It examines whether ICT has given rise to the establishment of new notions of space and place, identifying new design challenges for cities and rethought approaches to the production of space. In view of the latter, the chapter subsequently questions the manner with which digital media may facilitate inclusive design of public spaces. In order to address this objective, the chapter illustrates some interesting empirical data emanating from literature and research projects based in the UK, Poland and Malta. The case studies in the literature illustrate how ICTs are being used as tools within participatory processes for the inclusive design of urban public and recreational spaces and in order to gauge citizen/user expectations towards urban space. The chapter finally attempts to redefine public participation through ICT and to frame the above discussion within the potentially newly redefined role of urban designers involved in such processes. The underlying question to be addressed in this chapter, therefore, has to deal with the manner with which urban professionals may effectively achieve inclusive participatory design, particularly in light of new phenomena brought about by the mediated city and with the potential of this newly obtained and enriched data.
Using ICT in the Management of Public Open Space as a Commons
Authors: Artopoulos Georgios , Arvanitidis Paschalis , Suomalainen Sari
Published: March 2019

The chapter defines public open space as a commons and explores innovative ways for its management and sustainable development through the use of new information and communication technologies. It argues that hybrid conglomerates of space and technological interfaces provide this possibility. Section 2 defines common pool resources and discusses issues of its management, before it moves to identify public open space as a commons and to outline key directives for governance. Section 3 outlines the new ICT and considers practices and technologies that can be used in order to enhance community identity, social interaction and user engagement in the governance of the public open space as a commons. Finally, the last section concludes this chapter with some remarks on the conditions under which the hybrid of a public open space with ICT features could be approached as yet another kind of ‘soft’ type of common pool resource.
Heterotopic Landscapes: From GreenParks to Hybrid Territories
Authors: Patrício Catarina , Breser Christoph , Ioannidis Konstantinos
Published: March 2019

This chapter develops an interest in clarifying the meaning of cyberparks through an interrogation beyond its material preconditions. A cyberpark, as a fold in space generated by a hybrid emergent form of co-mediated space, is a disjunctive combination: it presupposes an encounter between open public urban places and the use of ICT tools. Outstretched beyond its physical manifestation as a place of encounter, a «heterotopic» reading might reveal that the subject is displaced in many different ways, from the analogue to the digital landscape, and from the specificity of the local to the universal of the global web. It is in such transferences that several worlds blend, both in its symbolic function and social significance. Impacts of such «Other Spaces» on the nature of human being’s behaviours can be critically reflected by the consideration of the social role of ICTs as tools of alienation through reinforced governances. Hence the question of creating «non-places» arouses, affording both a consensual appropriation process and the representative commodity networks, that henceforth includes natural, technical and human aspects and at the same time constitutes hybrid identities at the interfaces of its users, subjects, objects and places.
Modelling Co-creation Ecosystem for Public Open Spaces
Authors: Skarzauskiene Aelita , Maciuliene Monika , Ivanova-Radovanova Petja
Published: March 2019

Co-creation can be defined as the involvement of citizens in the initiation and/or the design process of public services in order to (co)create beneficial outcomes and value for society. Mediated public open spaces are ideal environments for co-creation to emerge due to the involvement of the community and ICT in the knowledge creation. The aims of the research presented in the chapter are two-fold: to conduct a mapping activity in order to collect the insights on civic technologies promoting the creation of open public spaces through the use of ICT and to define the critical dimensions in designing co-creative ecosystems. The mapping strategy was conducted by evaluating the civic technologies in Lithuania and Bulgaria. The insights from the empirical exercise allow to draw managerial and organizational recommendations for strengthening the collective efforts of citizens, IT developers, public and governmental institutions in creating open, inclusive and reflective open public spaces.
Using ICTs for the Improvement of Public Open Spaces: The Opportunity Offered by CyberParks Digital Tools
Authors: Osaba Eneko , Pierdicca Roberto , Duarte Tiago , Bahillo Alfonso , Mateus Diogo
Published: March 2019

In the last decade, the potential of mobile devices for augmenting outdoor experience opened up new solutions, whose value is twofold. On one hand, users can experience new forms of interaction with space. On the other, stakeholders can have access to the so-called User Generated Data, that is different types of information related to public spaces that could be used to improve their conception of space. In line with this, several digital tools have been developed and tested within the framework of CyberParks COST Action TU-1306 with the intention of exploring how information and communication technologies (ICTs) can contribute to the improvement of Public Open Spaces (POS). In this way, this chapter aims to study the relationship between ICTs and POS, focused on the opportunities offered by three different digital tools: the WAY-CyberParks, the EthnoAlly, and the CyberCardeto. The main advantages of using these digital tools are: (1) the real-time data gathering, (2) maintaining an updated database, (3) collecting traces of different activities and users’ groups “at the same time and space”, and (4) recording their opinion and preferences, via text, video, sound or pictures. Furthermore, the chapter attempts to analyse distinct types of results produced by their use, based on different study cases where the digital tool has been tested. The data obtained in these places serve to demonstrate the features and type of data gathered. With these case studies, the chapter attempts to highlight the main potential of each platform as related to different stakeholders and users.
A Pedagogical Model for CyberParks
Authors: Bonanno Philip , Klichowski Michal , Lister Penelope
Published: March 2019

This chapter discusses the recent conceptual developments about CyberParks and their educational potential. Key learning characteristics and pedagogical principles will be identified through a review of learning theories and studies from cognitive neuroscience. Relevant pedagogical models are reviewed to develop one that describes learning in CyberParks, which will be used to design and evaluate learning in such context. An innovative connectivist-inspired process-oriented pedagogical model is proposed to serve as a signpost in the process of developing adaptive expertise through which new pedagogies and innovative uses of CyberParks address the evolving needs of citizens.
Teenagers’ Perception of Public Spaces and Their Practices in ICTs Uses
Authors: Menezes Marluci , Arvanitidis Paschalis , Smaniotto Costa Carlos , Weinstein Zvi
Published: March 2019

The new information and communications technologies are expanding human connectivity, reconfiguring urban spatialities and generating a kind of social space that spans real and virtual, personal and impersonal, private and public. As a result, the space and time boundaries become blurred, giving rise to novel needs for, and practices of, public space usage. However, the ways in which these new practices affect public space engagement and public life in general, remain yet unclear. In addition, variations might exist due to differences in local culture and conditions, or due to specific lifestyles and behaviours favouring isolation and privatism or, at best, interaction only with close friends and kin. The above issues become even more critical for young people, who born in a digital era are able to handle new technologies with utmost ease. This chapter sheds light on the related perceptions and practices of adolescents. Structured interviews were applied to eight teenagers living in Hannover (Germany), Lisbon (Portugal), Tel Aviv (Israel) and Volos (Greece) to gather focused, qualitative and textual data. It examines how young people of distinct sociocultural contexts perceive and use both public spaces and digital technologies. This enables to identify emergent logics, needs and patterns of socialization and public space engagement placing specific emphasis on the role information technologies can play in them.
Enhanced di-Higgs production in the two Higgs doublet model
Authors: Babu K. S. , Jana Sudip
Published: March 2019

Abstract

We show that the rate for di-Higgs production at the LHC can be enhanced by a factor as large as 25 compared to the Standard Model value in the two Higgs doublet model, while being consistent with the known properties of the observed Higgs boson h. There are correlated modifications in

$$ t\overline{t}h $$

t

t
¯

h

and resonant Zh production rates, which can serve as tests of this model. Our framework treats both Higgs doublets on equal footing, each with comparable Yukawa couplings to fermions. The Cheng-Sher ansatz for multi-Higgs doublet model is shown to be strongly disfavored by current experiments. We propose a new ansatz for the Yukawa couplings of the Higgs doublets Φ
a
is proposed, where Y

ij

(a)
 = C

ij

(a)
 · min{m

i
, m

j
}/v, with C

ij

(a)
being order one coefficients, mi the mass of fermion i and v the electroweak vacuum expectation value. Such a pattern of couplings can explain the observed features of fermion masses and mixings and satisfies all flavor violation constraints arising from the exchange of neutral Higgs bosons. The rate for μ → eγ decay and new contributions to CP violation in

$$ {B}_s-{\overline{B}}_s $$

B
s

−

B
¯

s

mixing are predicted to be close to the experimental limits.
Instability of BTZ black holes in parity-even massive gravity
Authors: Jafari Ghadir , Soltanpanahi Hesam
Published: March 2019

Abstract

We investigate the linearized equations of motion in three dimensional Born-Infeld gravity theory. Motivated by this model, we calculate the quasinormal modes of BTZ black hole solutions of parity-even gravity theories in three dimensions by using numerical methods. The results are classified in three families and they are so accurate such that it allows us to propose analytical form for the quasinormal frequencies. We find new quasinormal modes which have been missing in the literature of the analytical studies of three dimensional massive gravitons. These new modes do not have the known tower structure and they are purely imaginary for any value of the angular momenta. Considering the complete set of the quasinormal modes, we show that the BTZ black hole solutions are unstable for any value of the parameters of the theory. We confirm our numerical results by computing the new eigenmodes analytically at zero angular momentum.