bluuebunny/crossref_metadata_2025_split huggingface dataset:
Green Thermochromic Materials: A Brief Review
Authors: Crosby Patrice H. N. , Netravali Anil N. 
Published: July 2022

AbstractGreen thermochromic materials are of great interest in many applications. Thermochromic and phase change materials are commonly used as smart devices to facilitate temperature sensing and passive heating/cooling systems, respectively. Since most of the current thermochromic materials are nondegradable, toxic, and/or nongreen, there is great opportunity to develop greener materials with high performance considering the wide range of materials that can exhibit thermochromism. This concise review distinguishes the different forms, phases, and chemical structures of thermochromic materials. A brief history of thermochromism is reviewed and a general distinction between reversible and irreversible thermochromism is provided. A general definition of green materials is provided, recent advances in the emerging field are critically discussed as well as future applications. This review also provides brief but thorough understanding of mechanistic pathways of this phenomenon in materials and the constituent requirements of green materials such that new systems can be designed using nontoxic, biobased, and/or biodegradable materials. Such green thermochromic materials will expand their use significantly.
Fluid Layered Ferroelectrics with Global C∞v Symmetry
Authors: Kikuchi Hirotsugu , Matsukizono Hiroyuki , Iwamatsu Koki , Endo Sota , Anan Shizuka , Okumura Yasushi 
Published: July 2022

AbstractFerroelectricity in fluid materials, which allows free rotation of molecules, is an unusual phenomenon raising cutting‐edge questions in science. Conventional ferroelectric liquid crystals have been found in phases with low symmetry that permit the presence of spontaneous polarization. Recently, the discovery of ferroelectricity with high symmetry in the nematic phase has attracted considerable attention. However, the physical mechanism and molecular origin of ferroelectricity are poorly understood and a large domain of macroscopically oriented spontaneous polarization is difficult to fabricate in the ferroelectric nematic phase. This study reports new fluid layered ferroelectrics with the C∞v symmetry in which nearly complete orientation of the spontaneous polarization remains stable under zero electric field without any orientation treatment. These ferroelectrics are obtained by simplifying the molecular structure of a compound with a known ferroelectric nematic phase, although the simplification reduced the dipole moment. The results provide useful insights into the mechanism of ferroelectricity due to dipole–dipole interactions in molecular assemblies. The new ferroelectric materials are promising for a wide range of applications as soft ferroelectrics.
Bubble breakup and boiling heat transfer in Y‐shaped bifurcating microchannels
Authors: Yan Zhe , Huang Haoxiang , Pan Zhenhai 
Published: July 2022

AbstractThree‐dimensional simulations are performed to study the bubble breakup and boiling heat transfer in Y‐shaped bifurcating microchannels with different heat fluxes and bifurcating angles. Results show that the breakup regime for continuously growing bubble changes from tunnel breakup to obstructed breakup as the heat flux increases. Interestingly, the pinch‐off stage of bubble breakup becomes inconspicuous in small acute‐angle bifurcating microchannel. The flow structure changes from smooth mode to twining mode as the bifurcating angle increases. The bubble transit leads to the shrink or disappearance of vortex. The heat transfer is tightly associated with bubble dynamics. The negative heat transfer enhancement is observed at low heat flux and it is eliminated at high heat flux. The heat transfer is enhanced with the increase in heat flux, while the effect of bifurcating angle is relatively complex. The present study provides new insights into the two‐phase flow in bifurcating structures.
Paid sick leave among US private sector employees
Authors: Johnson Candice Y. , Said Kristen , Price Ashley E. , Darcey Dennis , Østbye Truls 
Published: July 2022

AbstractBackgroundInequities in US employees' access to paid sick leave are known, but it is not clear whether they are increasing or decreasing over time. More than two dozen state and local paid sick leave laws were recently enacted, many with the stated goal of reducing inequities in access to paid sick leave. We examined how inequities in access to paid sick leave have changed over time, focusing on the years when these laws were coming into effect.MethodsPrivate sector employees participating in the National Health Interview Survey between 2006 (before laws came into effect) and 2018 (after most came into effect) reported if they had paid sick leave in their main job. We examined how differences in access to paid sick leave by Census region, race/ethnicity, work hours, and educational attainment changed over time.ResultsThe percentage of employees with access to paid sick leave increased from 56% in 2006 to 61% in 2018, with most of the increases in access occurring in the West. Inequities by race/ethnicity decreased substantially between 2015 and 2018, the years when most paid sick leave laws came into effect. This change was driven by Hispanic and Latino workers rapidly gaining access to paid sick leave during this time. Differences in access to paid sick leave by work hours and education attainment remained stable over time.ConclusionsInequities in access to paid sick leave remain. Paid sick leave laws could be effective means to increase access to paid sick leave and equalize access.
Iodocyclization of 2‐Methylthiophenylacetylenes to 3‐Iodobenzothiophenes and their coupling Reactions under More Sustainable Conditions
Authors: Mancuso Raffaella , Lettieri Melania , Strangis Romina , Russo Patrizio , Piccionello Antonio Palumbo , De Angelis Sara , Gabriele Bartolo 
Published: July 2022

AbstractWe report the first example of iodocyclization of readily available 2‐methylthiophenylacetylenes in a deep eutectic solvent (ChCl/urea 1/2, mol/mol) as recyclable and more sustainable solvent with respect to the classical VOCs employed so far. The process successfully afforded a variety of 3‐iodobenzothiophenes in good to high yields starting from differently substituted substrates, with the possibility to recycle the DES several times without appreciable lowering of the product yield. The 3‐iodothiophenes thus synthesized are known to be important precursors of biologically active molecules and functionalized heterocycles, and were successfully employed for performing representative Sonogashira and Suzuki cross‐coupling reactions. The solvent‐catalyst system could be conveniently recycled several times without any loss of activity in both coupling processes, thus further demonstrating the practical usefulness of our approach.
Blood‐based bioenergetic profiling reveals differences in mitochondrial function associated with cognitive performance and Alzheimer's disease
Authors: Mahapatra Gargi , Gao Zhengrong , Bateman James R. , Lockhart Samuel Neal , Bergstrom Jaclyn , DeWitt Amber Renee , Piloso Jemima Elizabeth , Kramer Philip Adam , Gonzalez‐Armenta Jenny L. , Amick Kimberly Allison , Casanova Ramon , Craft Suzanne , Molina Anthony J. A. 
Published: July 2022

AbstractIntroductionDespite evidence for systemic mitochondrial dysfunction early in Alzheimer's disease (AD) pathogenesis, reliable approaches monitoring these key bioenergetic alterations are lacking. We used peripheral blood mononuclear cells (PBMCs) and platelets as reporters of mitochondrial function in the context of cognitive impairment and AD.MethodsMitochondrial function was analyzed using complementary respirometric approaches in intact and permeabilized cells from older adults with normal cognition, mild cognitive impairment (MCI), and dementia due to probable AD. Clinical outcomes included measures of cognitive function and brain morphology.ResultsPBMC and platelet bioenergetic parameters were lowest in dementia participants. MCI platelets exhibited higher maximal respiration than normocognitives. PBMC and platelet respiration positively associated with cognitive ability and hippocampal volume, and negatively associated with white matter hyperintensities.DiscussionOur findings indicate blood‐based bioenergetic profiling can be used as a minimally invasive approach for measuring systemic bioenergetic differences associated with dementia, and may be used to monitor bioenergetic changes associated with AD risk and progression.Highlights
Peripheral cell bioenergetic alterations accompanied cognitive decline in older adults with mild cognitive impairment (MCI) and Alzheimer's disease (AD) and related dementia (DEM).
Peripheral blood mononuclear cells (PBMC) and platelet glucose‐mediated respiration decreased in participants with dementia compared to normocognitive controls (NC).
PBMC fatty‐acid oxidation (FAO)‐mediated respiration progressively declined in MCI and AD compared to NC participants, while platelet FAO‐mediated respiration exhibited an inverse‐Warburg effect in MCI compared to NC participants.
Positive associations were observed between bioenergetics and Modified Preclinical Alzheimer's Cognitive Composite, and bioenergetics and hippocampal volume %, while a negative association was observed between bioenergetics and white matter hyperintensities.
Systemic mitochondrial dysfunction is associated with cognitive decline.
Regulatory effect of gut microbes on blood pressure
Authors: Yan Dong , Sun Ye , Zhou Xiaoyue , Si Wenhao , Liu Jieyu , Li Min , Wu Minna 
Published: July 2022

AbstractHypertension is an important global public health issue because of its high morbidity as well as the increased risk of other diseases. Recent studies have indicated that the development of hypertension is related to the dysbiosis of the gut microbiota in both animals and humans. In this review, we outline the interaction between gut microbiota and hypertension, including gut microbial changes in hypertension, the effect of microbial dysbiosis on blood pressure (BP), indicators of gut microbial dysbiosis in hypertension, and the microbial genera that affect BP at the taxonomic level. For example, increases in Lactobacillus, Roseburia, Coprococcus, Akkermansia, and Bifidobacterium are associated with reduced BP, while increases in Streptococcus, Blautia, and Prevotella are associated with elevated BP. Furthermore, we describe the potential mechanisms involved in the regulation between gut microbiota and hypertension. Finally, we summarize the commonly used treatments of hypertension that are based on gut microbes, including fecal microbiota transfer, probiotics and prebiotics, antibiotics, and dietary supplements. This review aims to find novel potential genera for improving hypertension and give a direction for future studies on gut microbiota in hypertension.
A novel n‐type poly(sulfonic acid diphenyl aniline) and its nanocomposites with large Seebeck coefficient enhanced with external magnetic fields
Authors: Huner Keziban , Karaman Ferdane 
Published: July 2022

AbstractMost of the polymeric thermoelectric materials represent p‐type conductivity; however, those of n‐type are very few. We report some novel n‐type polymeric materials, which are poly(sulphonic acid diphenyl aniline) (PSDA) and its nanocomposites with polythiophene (PTh). They were synthesized in aqueous media using chemical oxidation polymerization process under the external magnetic field where the flux intensities are 0, 1.5, 2.5, and 4.6 kGauss. As the magnetic flux density increases, absolute values of Seebeck coefficient of PSDA and PSDA/PTh nanocomposite films increased however their conductivity did not changed. The negative sign of Seebeck coefficients indicated that PSDA and PSDA/PTh nanocomposites have n‐type conductivity. The highest Seebeck coefficient and power factor were obtained as −2535 μV/K and 0.031 μW/mK2, respectively, for PSDA synthesized under 4.6 kGauss magnetic flux. Changes of the Seebeck coefficient were examined in detail with XPS analysis. FTIR, UV–vis spectroscopy, DLS, and XRD analyzes were also performed for the characterization of the polymers. Their surface morphologies were examined by STEM.
Modified hydroxyapatite improves the corrosion resistance of the epoxy coating
Authors: Peng Bokai , Yu Zongxue , Chen Legang , Liao Kexi , Chen Haidong , Guo Yuchi , Liu Yucheng 
Published: July 2022

AbstractIn this study, HAp(hydroxyapatite) was prepared by hydrothermal method and was successfully modified by APTES (aminopropyltriethoxysilane) to obtain APTES‐HAp nanomaterial. Firstly, the microstructure and surface morphology of HAp and APTES‐HAp were studied by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM), and it was confirmed that HAp and APTES‐HAp composites were successfully synthesized. Secondly, SEM analysis is used to study the dispersion of APTES‐HAp in epoxy resin, and it is proved that the dispersion of HAp modified by APTES is greatly improved. Finally, the corrosion resistance of the composite coating was studied in detail by electrochemical impedance spectroscopy (EIS). The results show that the APTES‐HAp /EP composite coating impedance modulus remains 107. The breakpoint frequency (fb) is always the minimum after 30 days of immersion, which proves that the corrosion resistance of APTES‐HAp /EP composite coating is significantly improved APTES‐HAp/EP. The improvement of corrosion resistance is mainly attributed to the following two points: APTES‐HAp has good uniform dispersion and interfaces compatibility in epoxy resin, forming an effective barrier network. On the other hand, layered HAp forms physical barriers and maze effects on corrosive media.
Preparation of a water‐dispersible nano‐photoinitiator oriented towards 3D printing hydrogel with visible light
Authors: Gu Xiang , Shi Xiaokun , Wu Jiadong , Zhang Yiming , Dong Lize , Gong Yuxuan , Meng Qinghua , Zhang Chongyin 
Published: July 2022

AbstractIn this article, a preparation method of a water‐dispersible photoinitiator, which can be used for three‐dimensional (3D) printing of the hydrogel and can be initiated under visible light is proposed. The oil‐soluble photoinitiator 2,4,6‐trimethylbenzoyl‐diphenylphosphine oxide (TPO) is nano‐wrapped with surfactant Tween 20 to obtain the oil‐in‐water (O/W) miniemulsion, and then it is successfully transformed into water‐dispersible nanospheres without the use of organic solvents or crystallization inhibitors. The morphology and optical properties were characterized by transmission electron microscopy (TEM), particle size analysis and ultraviolet–visible (UV–Vis) spectroscopy. Subsequently, the water‐dispersible nano‐photoinitiator was used to realize the photopolymerization of acrylamide/N,N′‐methylenebisacrylamide hydrogel under visible light (405 nm). Then, the micromorphology of the photocuring process of the hydrogel was observed by TEM and the photocuring activity of the initiator was evaluated. Finally, a viscosifier suitable for AM/MBA hydrogel system was screened out, and the direct ink writing (DIW) 3D printing of the hydrogel was successfully realized by using this nano‐photoinitiator.
Microencapsulation of bisphenol A‐bis(diphenyl phosphate) by Pickering emulsions polymerization and its application in water‐borne polyacrylic acid coatings
Authors: Zhao Yunting , Gao Jing , Dong Chen , Ning Kegong , He Yongjun 
Published: July 2022

AbstractFor improving the compatibility of oil‐based flame retardants and waterborne substrates, Bisphenol A‐bis(diphenyl phosphate) (BDP) is used as the dispersed phase, sodium alginate (SA) solution as the continuous phase, and hydrophilic silica as the emulsifier in the preparation of stable oil‐in‐water (O/W) Pickering emulsions. Then, the emulsions are added into CaCl2 solution in the atomized form to polymerize the aqueous phase to calcium alginate (CA) and to obtain BDP/SiO2/CA microcapsules. BDP/SiO2/CA microcapsules are used as a flame retardant to improve the fire safety of waterborne polyacrylic acid (PAA) coatings. To verify that BDP/SiO2/CA is successfully prepared, Fourier‐transform infrared spectra (FTIR) and scanning electron microscopy (SEM) are used after microencapsulation. The results show that the physical barrier formed by the SiO2 particle layer has successfully stabilized the BDP in the CA gel network. Subsequently, the flame retardance of PAA with BDP/SiO2/CA is tested using limiting oxygen index (LOI) test and cone calorimeter(CONE) test. Compared with pure PAA, when BDP/SiO2/CA (4:6) microcapsules are added at 20 wt %, the LOI of the PAA coating is increased from 18.6% to 28.4%, the peak heat release rate (PHRR) value of that is reduced by 52.66%. The microcapsules endow oily BDP hydrophilicity and good compatibility with waterborne PAA coatings.
Enhanced thermal conductivity of polycarbonate‐based composites by constructing a dense filler packing structure consisting of hybrid boron nitride and flake graphite
Authors: Bai Yang , Zhou Shengtai , Lei Xue , Zou Huawei , Liang Mei 
Published: July 2022

AbstractIn this work, thermally conductive yet electrically insulative polycarbonate (PC)‐based composites with hybrid boron nitride (BN) and flake graphite (Gt) network structure were prepared by high shear injection molding process. A synergy in improving the thermal conductivity of PC was observed with the hybrid loading of BN and Gt. Results showed that the in‐plane thermal conductivity of PC/BN 30 wt%/Gt 16 wt% composite reached as high as 4.08 W/mK, which were 189% and 358% higher than that of PC/BN 30 wt% and PC/Gt 16 wt% composites, respectively. The preferred orientation of planar fillers and interconnection between added fillers were indispensable to the significant increase of in‐plane thermal conductivity, as corroborated by X‐ray diffraction, rheology and scanning electron microscope observations. Moreover, the electrical resistivity of PC/BN 30 wt%/Gt composites was higher than 1014 Ω cm, which shows potential application in thermal management areas such as advanced electronic devices and battery units among others.
Superior stretchable and tough P(AA‐co‐AAm)/silica hybrid hydrogels enabled by acid‐mediated radiation polymerization
Authors: Tian Yukun , Hong Yongzhi , Wang Yunlong , Tian Yuan , Wang Zhihao , Ai Meixing , Ma Jun 
Published: July 2022

AbstractThe emerging stretchable and tough hydrogels find their extraordinary contributions in widespread use. However, the applicability of existing tough hydrogels in harsh environments like highly acidic stomachs has remained a challenge. Here, we develop superior stretchable and tough P(AA‐co‐AAm)/SiO2 hybrid hydrogels through radiation‐induced polymerization and crosslinking in the presence of acids. The performance of the nanocomposite gels was optimized by altering fabrication variables including acid concentration, monomer composition and absorbed dose. The mechanic tests show that the protonated hybrid hydrogels displayed a high elongation at break (1919%), fracture strength (117 kPa), and compressive strength at 50% strain (126 kPa). These values are superior to those of conventional polyelectrolyte hydrogels and expect to significantly broaden the application. The proposed strategy is quite general and offers an alternative strategy to develop tough hydrogels.
Feedback‐Error Learning for time‐effective gait trajectory tracking in wearable exoskeletons
Authors: Figueiredo Joana , Fernandes Pedro Nuno , Moreno Juan C. , Santos Cristina P. 
Published: July 2022

AbstractThe use of exoskeletons in gait rehabilitation implies user‐oriented and efficient responses of exoskeletons' controllers with adaptability for human‐robot interaction. This study investigates the performance of a bioinspired hybrid control, the Feedback‐Error Learning (FEL) controller, to time‐effectively track user‐oriented gait trajectories and adapt the exoskeletons' response to dynamic changes due to the interaction with the user. It innovates with a controller benchmarking analysis. FEL combines a proportional‐integral‐derivative (PID) feedback controller with a three‐layer neural network feedforward controller that learns the inverse dynamics of the exoskeleton based on real‐time feedback commands. FEL validation involved able‐bodied subjects walking with knee and ankle exoskeletons at different gait speeds while considering gait disturbances. Results showed that the FEL control accurately (tracking error <7%) and timely (delay <30 ms) tracked gait trajectories. The feedforward controller learned the inverse dynamics of the exoskeletons in a time compliant for clinical use and adapted to variations in the gait trajectories, such as speed and position range, while the feedback controller compensated for random disturbances. FEL was more accurate and time‐effective controller for tracking gait trajectories than a PID control (error <27%, delay <260 ms) and a lookup table feedforward combined with PID control (error <17%, delay >160 ms). These findings aligned with FEL's time‐effectiveness favors its use in wearable exoskeletons for repetitive gait training.
Design and Synthesis of Ag‐based Catalysts for Electrochemical CO2 Reduction: Advances and Perspectives
Authors: Yang Hu , Huang Jialu , Yang Hui , Guo Qiyang , Jiang Bei , Chen Jinxing , Yuan Xiaolei 
Published: July 2022

AbstractAg‐based nanocrystals have emerged as an important candidate for CO2 reduction reaction (CO2RR) owing to the increasing amount of CO2 in the atmosphere, which has shown a propensity to alleviate environmental problems and produce high value‐added chemicals. This paper reviews the surface and interface engineering of Ag‐based catalysts towards CO2RR, which involve in the morphology control, composition manipulation, and support effects. Various synthesis approaches are presented to discuss their influence on the size, crystal structure and morphology of Ag‐based catalysts, including pure Ag NPs, Ag‐based alloys, Ag/metal oxides composites as well as Ag/carbon materials. Next, the development of Ag‐based surface and interface engineering that is essential to accelerate the formation of CO and its further conversion to C1 or even multicarbon products is systematically discussed. Finally, we give a short conclusion, and perspectives on the rational design of Ag‐based catalysts based on surface and interface engineering will be discussed.