bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of immobilized zinc oxide photocatalysts for wastewater treatment: Application to methylene blue degradation
Authors: Karavasilis Michalis V. , Tsakiroglou Christos D. 
Published: May 2021

AbstractZinc‐oxide (ZnO) nanoparticles were immobilized on borosilicate glass spheres with treatment of zinc acetate dihydrate (ZAC) solution, and calcination at 400–450°C. The isotherm and kinetic parameters of methylene blue (MB) sorption on ZnO‐coated glass beads were estimated from batch sorption tests in darkness. An ultraviolet (UV)‐lamp with nominal power of 6 W and emission peak at 375 nm was used as a light source. Batch experiments of MB photodegradation were performed in a double‐wall glass reactor. Continuous flow tests were conducted in a poly(methyl methacrylate) (PMMA) annular photoreactor by recirculating the MB solution between it and a feed tank. All results were interpreted with dynamic models based on a two‐step process consisting of MB adsorption/desorption, and adsorbed MB surface reaction. The intense stirring caused by air bubbling or aqueous phase flow triggers the detachment of catalyst mass from substrate, the partial renewal of immobilized catalyst surface exposed to UV‐radiation, and the enhancement of the apparent maximum MB sorption capacity by total ZnO mass. The fast MB adsorption leads to an almost constant concentration of adsorbed MB at equilibrium, while the surface photocatalytic reaction is the MB degradation rate‐controlling step. Comparable values of the kinetic constant of surface reaction are estimated from batch and continuous flow tests, for repeated cycles of photocatalysis.
Reprogramming oral epithelial keratinocytes into a pluripotent phenotype for tissue regeneration
Authors: Bazina Fayrouz , Brouxhon Sabine M. , Kyrkanides Stephanos 
Published: May 2021

AbstractObjectivesWe set out to reprogram adult somatic oral epithelial keratinocytes into pluripotent cells for regenerative dentistry.Setting and Sample populationImmortalized murine oral keratinocyte cell (IMOK) line raised from adult mouse mucosa were cultured in vitro in our studies.Materials and MethodsAdult murine oral epithelial keratinocytes were chronically treated with TGF‐β1 in vitro, and the expression of Oct4, Nanog, Sox2 and Nestin, as well as specific homeobox Gata and Pax gene family members were investigated.ResultsWe documented the induction of stem factors linked with pluripotency and/or the maintenance and regulation of stem‐cell self‐renewal in oral epithelial keratinocytes by TGFβ1. Moreover, we discovered that this TGF‐β1‐induced increase in Oct4, Nanog, Sox2 and Nestin was inhibited by SB431542, suggesting that TGF‐β1 signals via the TGF‐βRI receptor to induce pluripotency and stemness.ConclusionsAdult oral epithelial keratinocytes treated chronically with TGF‐β1 acquired phenotypic characteristics consistent with pluripotent stem cells, highlighting the facileness of reprogramming adult oral keratinocytes into an unlimited supply of pluripotent stem cells.
Peace education in secondary schools of Mizoram
Authors: Mishra Lokanath 
Published: May 2021

AbstractPeace education aims to equip future citizens with the necessary knowledge, attitudes, and skills to acknowledge and respect all kinds of diversity and understanding with human dignity. This article is based on empirical research to examine the practices of peace‐related activities in secondary schools of Mizoram. Mixed method was employed in this study. The secondary school students and the teachers of Mizoram were the target populations of the study. The total sample of the study comprised of 200 students: 100 boys and 100 girls of class IX; 100 teachers from 20 government secondary schools of Mizoram were drawn through a simple random sampling technique. A self‐made questionnaire consisting of 23 items, semi‐structured interview, and Focus Group Discussion were used as the techniques of data collection. The study showed that peace education components embedded in the existing curriculum were being taught through cocurricular and extracurricular activities. This article concludes by suggesting that teachers need to consider and include the guiding principles of peace and should encourage students to develop their critical thinking, reasoning, awareness of societal problems and issues, broadening their outlook, and concentrating on studies and to be associated with cocurricular activities.
A novel RANKL‐targeted flavonoid glycoside prevents osteoporosis through inhibiting NFATc1 and reactive oxygen species
Authors: Hong Guoju , Chen Zhenqiu , Han Xiaorui , Zhou Lin , Pang Fengxiang , Wu Rishana , Shen Yingshan , He Xiaoming , Hong Zhinan , Li Ziqi , He Wei , Wei Qiushi 
Published: May 2021

AbstractBackground and purposeOsteoporosis is characterized by excessive bone resorption due to enhanced osteoclast activation. Stimulation of nuclear factor of activated T cells 1 (NFATc1) and accumulation of reactive oxygen species (ROS) are important mechanisms underlying osteoclastogenesis. Robinin (Rob) is a flavonoid glycoside that has shown anti‐inflammatory and antioxidative effects in previous studies, but little is known about its effects on bone homeostasis. The purpose of our research was to investigate whether Rob could prevent bone resorption in ovariectomized (OVX) mice by suppressing osteoclast production through its underlying mechanisms.MethodsThe docking pose of Rob and RANKL was identified by protein‐ligand molecular docking. Rob was added to bone marrow macrophages (BMMs) stimulated by nuclear factor‐κB (NF‐κB) ligand (RANKL). The effects of Rob on osteoclastic activity were evaluated by positive tartrate resistant acid phosphatase (TRAcP) staining kit and hydroxyapatite resorption assay. RANKL‐induced ROS generation in osteoclasts was detected by H2DCFDA and MitoSox Red staining. The classic molecular cascades triggered by RANKL, such as NF‐κB, ROS, calcium oscillations, and NFATc1‐mediated signaling pathways, were investigated using Fluo4 staining, western blot, and quantitative real‐time polymerase chain reaction. In addition, an OVX mouse model mimicking estrogen‐deficient osteoporosis was created to evaluate the therapeutic effects of Robin vivo.ResultsComputational docking results showed that Rob could bind specifically to RANKL's predicted binding sites.In vitro, Rob inhibited RANKL‐mediated osteoclastogenesis dose‐dependently without obvious cytotoxicity at low concentrations. We also found that Rob attenuated RANKL‐induced mitochondrial ROS production or enhanced activities of ROS‐scavenging enzymes, and ultimately reduced intracellular ROS levels. Rob abrogated the RANKL‐induced mitogen‐activated protein kinase (MAPK) and NF‐κB signaling pathways, and subsequently blocked NFATc1 signaling and TRAcP expression. In addition, Rob inhibited osteoclast proliferation by downregulating the expression of osteoclast target genes (Acp5,Cathepsin K,Atp6v0d2, Nfact1,c‐Fos, andMmp9) and reducing Ca2+oscillations. Ourin vivoresults showed that Rob reduced bone resorption in OVX animal model by repressing osteoclast activity and function.ConclusionsRob inhibits the activation of osteoclasts by targeting RANKL and is therefore a potential osteoporosis drug.
Interaction of CSF α‐synuclein and amyloid beta in cognition and cortical atrophy
Authors: Lee Young‐gun , Jeon Seun , Kang Sung Woo , Park Mincheol , Baik Kyoungwon , Yoo Han Soo , Chung Seok Jong , Jeong Seong Ho , Jung Jin Ho , Lee Phil Hyu , Sohn Young Ho , Evans Alan C. , Ye Byoung Seok ,   and the Alzheimer's Disease Neuroimaging Initiative
Published: May 2021

AbstractIntroductionLewy body–related pathology is commonly observed at autopsy in individuals with dementia, but in vivo biomarkers for α‐synucleinopathy are lacking.MethodsBaseline cerebrospinal fluid (CSF) biomarkers, polygenic risk score (PRS) for Parkinson's disease (PRS‐PD) and Alzheimer's disease (PRS‐AD), longitudinal cognitive scores, and magnetic resonance imaging were measured in 217 participants from the Alzheimer's Disease Neuroimaging Initiative. Linear mixed models were used to find the relationship of CSF biomarkers and the PRS with cognition and cortical atrophy.ResultsHigher PRS‐PD and PRS‐AD were associated with lower CSF α‐synuclein and amyloid beta (Aβ), respectively. Lower CSF α‐synuclein and the interaction of CSF α‐synuclein and Aβ were associated with lower cognitive scores and global cortical atrophy most prominently in the occipital cortex.DiscussionLower CSF α‐synuclein could be a biomarker for α‐synucleinopathy, and the simultaneous evaluation of CSF biomarkers for AD and CSF α‐synuclein could reveal the independent and interactive effects on cognition and cortical atrophy.
Valorization of CO2 into N‐alkyl Oxazolidin‐2‐ones Promoted by Metal‐Free Porphyrin/TBACl System: Experimental and Computational Studies
Authors: Damiano Caterina , Sonzini Paolo , Manca Gabriele , Gallo Emma 
Published: May 2021

AbstractThe cycloaddition of CO2 to N‐alkyl aziridines was efficiently promoted by the convenient TPPH2/TBACl binary catalytic system. The metal‐free procedure was effective for the synthesis of differently substituted N‐alkyl oxazolidin‐2‐ones in yields up to 100 % and excellent regioselectivities (up to 99 %). The mechanism of the reaction was proposed based on a DFT study which indicated the formation of an adduct between TPPH2 and TBACl as the effective catalytic active species.
Stereoselective Visible‐Light Catalyzed Cyclization of Bis(enones): A Viable Approach to the Synthesis of Enantiomerically Enriched Cyclopentane Rings
Authors: Medici Fabrizio , Resta Simonetta , Presenti Piero , Caruso Lucia , Puglisi Alessandra , Raimondi Laura , Rossi Sergio , Benaglia Maurizio 
Published: May 2021

AbstractPhotoredox catalytic cyclization of aryl enones in the presence of visible light, promoted either by metals or organic dyes, represent a valuable strategy for the synthesis of cycloalkanes. The development of a stereoselective version of such transformation, in the presence of the metal‐free catalyst Eosin Y was studied, with the aim to realize an efficient protocol for the in‐flow synthesis of enantiomerically enriched functionalized cyclopentane rings, taking advantage of the flow reactors technology. The use of a chiral auxiliary on the bisenone to be cyclized offers a straightforward and convenient option to exert a stereocontrol on the light‐driven cyclization. By exploiting Evans’ oxazolidinones, the stereoselective light‐driven cyclization affords, after the removal of the chiral auxiliary, a functionalized 1,2‐trans cyclopentane ring in up to 83/17 enantiomeric ratio. When the reaction was performed in continuo, in a homemade coil photoreactor, high yields were observed. The cyclization was also successfully realized in a 3D‐printed mesoreactor, without any change in the diastereoseletctivity of the process.
Visible Light‐Induced Metal‐Free and Oxidant‐Free Radical Cyclization of (2‐Isocyanoaryl)(methyl)sulfanes with Ethers
Authors: Xie Xiao‐Yu , Li Yang , Xia Yun‐Tao , Luo Kai , Wu Lei 
Published: May 2021

AbstractA novel cascade cyclization of (2‐isocyanoaryl) (methyl)sulfanes and ethers is developed. With 4CzIPN as a photocatalyst and the irradiation of blue LED light, ether radicals are efficiently generated without adding any oxidant, endowing the strategy with features of oxidant‐free, metal‐free, mild reaction conditions, and operational simplicity. This strategy provides efficient approach to access various ether‐containing benzothiazoles in acceptable to good yields.
Dynamic rocking response of a rigid planar block on a nonlinear hysteretic Winkler foundation
Authors: Lu Yang , Xiong Feng , Ge Qi 
Published: May 2021

AbstractA new design philosophy termed “rocking isolation” has been advocated in recent studies on soil–structure interaction (SSI) toward utilizing nonlinear foundation response for seismic protection of structures. Allowing structures to rock on their foundation enables nonlinearities arising from base uplifting and soil yielding to limit seismic actions on structures, contributing to resilient SSI systems with controllable residual deformation. The current work presents an improved Winkler‐based rocking foundation model as an efficient practical tool to calculate the dynamic response of a rocking isolation system idealized as a rigid rectangular block rocking on a nonlinear hysteretic foundation allowing for base uplift. Compared with existing Winkler models where coupled shear‐compressive soil behavior is usually ignored, improvements are made by using smooth biaxial hysteretic elements to describe the point‐wise constitutive relation between tractions and displacements at the base. The foundation model is calibrated and validated against published experimental and numerical simulation data on clayey foundations. Analytical expressions are derived to estimate foundation rocking stiffness and failure envelope which describes the interaction between ultimate resultant forces developed on the foundation. The free‐vibrational and seismic responses of a class of flexibly supported rigid rocking blocks are examined using the proposed model through nonlinear response‐history analyses. It is found that sliding due to the coupled shear‐compressive soil behavior tends to reduce free‐vibrational rocking response of blocks with smaller slenderness ratios, while it may increase or decrease seismic overturning potential of blocks on heavily loaded foundations.
Structural optimal hybrid control strategies employing dynamic dual units: inerter and spring
Authors: Liang Qigang , Li Luyu , Zhang Yu 
Published: May 2021

AbstractThe concepts of optimal hybrid control strategies in the time and frequency domains are proposed herein. The time‐domain optimal hybrid control (also called GangGang strategy) consists of two dynamic units, an inerter and a spring, which work with different force mechanisms at different time phases of vibrations. The inerter acts on the structure when the vibration phase is accelerated, whereas the spring works when the structure deviates from its initial position. The combination of the two piecewise working units achieves better performance than their individual full‐time operations. The working time phases of the two units are complementary, covering the entire vibration period. The hysteresis loops of them are also complementary in the quadrant coordinate system. Owing to the piecewise properties of the two units, the equivalent linearization system (ELS) of such systems is formulated, and a statistical linearization procedure is developed to obtain the equivalent linearization parameters. Then, a parametric study on the equivalent damping is performed through sensitivity analysis and a comparative analysis of the ELS was performed in terms of the standard deviation and peak displacement levels under stationary stochastic excitations. The frequency‐domain optimal hybrid control conforms with the concept of intelligent isolation. The inerter and spring units can be switched according to the excitation frequency by an on–off control benefitting structures subjected to excitations with definite frequency range.
On stock volatility forecasting based on text mining and deep learning under high‐frequency data
Authors: Lei Bolin , Liu Zhengdi , Song Yuping 
Published: May 2021

AbstractFew existing literatures used the text information of the public opinions as the input index for volatility forecasting. This paper uses the text comment information of stockholders to construct a text sentiment factor that integrates the influence of comments and then combines other transaction information on volatility forecasting based on high‐frequency finance data with the deep learning model long short‐term memory (LSTM). The study finds that under the framework of the LSTM model, the forecasting accuracy for the volatility with the sentiment index is better than that of the LSTM model without the sentiment index and 10 traditional econometric models under the six loss functions. When compared with the traditional econometric model for multistep forecasting, the LSTM model is robust. With the addition of the public opinion index, the accuracy of LSTM is improved by 9.3%, 4.7%, 6.2%, 9.2%, 7.9%, and 16.9%, respectively, under the six evaluation criteria. The research in this article provides a more accurate, robust, and sustainable method for volatility forecasting in the context of big data.
Stock markets and exchange rate behavior of the BRICS
Authors: Salisu Afees A. , Cuñado Juncal , Isah Kazeem , Gupta Rangan 
Published: May 2021

AbstractRelying on the uncovered equity parity (UEP), we formulate a predictive model that links movements in exchange rate to stock return differential between the domestic market and the foreign (US) market. We also test for any probable asymmetric relationship between the two variables while also accounting for the role of observed common (global) factor such as oil price. We find a positive relationship between stock return differential and exchange rate return for three of the BRICS countries namely Brazil, India and South Africa, thus validating the UEP hypothesis, whereas a contrasting evidence is observed for China and Russia. We further establish the out‐of‐sample predictability of stock return differential for exchange rates of the BRICS while accounting for the role of observed common (global) factor, and asymmetry may further improve the forecast accuracy. The implications of our findings for portfolio diversification and foreign exchange management are highlighted.
Neural evidence for recognition of naturalistic videos in monkey hippocampus
Authors: Sakon John J. , Suzuki Wendy A. 
Published: May 2021

AbstractThe role of the hippocampus in recognition memory has long been a source of debate. Tasks used to study recognition that typically require an explicit probe, where the participant must make a response to prove they remember, yield mixed results on hippocampal involvement. Here, we tasked monkeys to freely view naturalistic videos, and only tested their memory via looking times for two separate novel versus repeat video conditions on each trial. Notably, a large proportion (>30%) of hippocampal neurons differentiated these videos via changes in firing rates time‐locked to the duration of their presentation on screen, and not during the delay period between them as would be expected for working memory. Many of these single neurons (>15%) contributed to both retrieval conditions, and differentiated novel from repeat videos across trials with trial‐unique content, suggesting they detect familiarity. The majority of neurons contributing to the classifier showed an enhancement in firing rate on repeat compared with novel videos, a pattern which has not previously been shown in hippocampus. These results suggest the hippocampus contributes to recognition memory via familiarity during free‐viewing.
Assessment of CHADFDM satellite‐based input dataset for the groundwater recharge estimation in arid and data scarce regions
Authors: Salehi Siavashani Nafiseh , Jimenez‐Martinez Joaquin , Vaquero Guillermo , Elorza Francisco J. , Sheffield Justin , Candela Lucila , Serrat‐Capdevila Aleix 
Published: May 2021

AbstractAquifer natural recharge estimations are a prerequisite for understanding hydrologic systems and sustainable water resources management. As meteorological data series collection is difficult in arid and semiarid areas, satellite products have recently become an alternative for water resources studies. A daily groundwater recharge estimation in the NW part of the Lake Chad Basin, using a soil–plant‐atmosphere model (VisualBALAN), from ground‐ and satellite‐based meteorological input dataset for non‐irrigated and irrigated land and for the 2005–2014 period is presented. Average annual values were 284 mm and 30°C for precipitation and temperature in ground‐based gauge stations. For the satellite‐model‐based Lake Chad Basin Flood and Drought Monitor System platform (CHADFDM), average annual precipitation and temperature were 417 mm and 29°C, respectively. Uncertainties derived from satellite data measurement could account for the rainfall difference. The estimated mean annual aquifer recharge was always higher from satellite‐ than ground‐based data, with differences up to 46% for dryland and 23% in irrigated areas. Recharge response to rainfall events was very variable and results were very sensitive to: wilting point, field capacity and curve number for runoff estimation. Obtained results provide plausible recharge values beyond the uncertainty related to data input and modelling approach. This work prevents on the important deviations in recharge estimation from weighted‐ensemble satellite‐based data, informing in decision making to both stakeholders and policy makers.
Ecohydrological modelling in a deciduous boreal forest: Model evaluation for application in non‐stationary climates
Authors: Marshall Adrienne M. , Link Timothy E. , Flerchinger Gerald N. , Nicolsky Dmitry J. , Lucash Melissa S. 
Published: May 2021

AbstractSoil moisture is an important driver of growth in boreal Alaska, but estimating soil hydraulic parameters can be challenging in this data‐sparse region. Parameter estimation is further complicated in regions with rapidly warming climate, where there is a need to minimize model error dependence on interannual climate variations. To better identify soil hydraulic parameters and quantify energy and water balance and soil moisture dynamics, we applied the physically based, one‐dimensional ecohydrological Simultaneous Heat and Water (SHAW) model, loosely coupled with the Geophysical Institute of Permafrost Laboratory (GIPL) model, to an upland deciduous forest stand in interior Alaska over a 13‐year period. Using a Generalized Likelihood Uncertainty Estimation parameterisation, SHAW reproduced interannual and vertical spatial variability of soil moisture during a five‐year validation period quite well, with root mean squared error (RMSE) of volumetric water content at 0.5 m as low as 0.020 cm3/cm3. Many parameter sets reproduced reasonable soil moisture dynamics, suggesting considerable equifinality. Model performance generally declined in the eight‐year validation period, indicating some overfitting and demonstrating the importance of interannual variability in model evaluation. We compared the performance of parameter sets selected based on traditional performance measures such as the RMSE that minimize error in soil moisture simulation, with one that is designed to minimize the dependence of model error on interannual climate variability using a new diagnostic approach we call CSMP, which stands for Climate Sensitivity of Model Performance. Use of the CSMP approach moderately decreases traditional model performance but may be more suitable for climate change applications, for which it is important that model error is independent from climate variability. These findings illustrate (1) that the SHAW model, coupled with GIPL, can adequately simulate soil moisture dynamics in this boreal deciduous region, (2) the importance of interannual variability in model parameterisation, and (3) a novel objective function for parameter selection to improve applicability in non‐stationary climates.