bluuebunny/crossref_metadata_2025 huggingface dataset:
Job stressors and burnout among nurses and primary‐care physicians working at a dedicated outpatient respiratory center for patients with suspected or confirmed COVID‐19
Authors: Nedić Olesja , Belkić Karen
Published: April 2023

Background

High burnout is reported among health professionals providing in‐patient care to patients with coronavirus disease 2019 (COVID‐19). Data are lacking on job stressors and burnout among health providers working in dedicated outpatient facilities for patients with suspected or confirmed COVID‐19.

Methods

This cross‐sectional study, using a parallel mixed‐methods design, was carried out in 2021−2022 among 22 nurses and 22 primary‐care physicians working at a COVID Outpatient Respiratory Center (CORC) (100% participation). Work conditions were assessed via the nurse‐ and physician‐specific Occupational Stressor Index (OSI) and occupational records. Measures of the outcome included the Copenhagen Burnout Index and current tobacco use.

Results

Time working in CORC displayed significant multivariate associations with personal, work‐ and patient‐related burnout among physicians and current tobacco use among nurses. Total OSI scores showed adjusted odds ratios for work‐related (1.35 (1.01 ± 1.79))(1.31 (0.99 ± 1.75)) and patient‐related burnout (1.35 (1.01 ± 1.81))(1.34 (1.01 ± 1.78)) among physicians and nurses, respectively. Numerous work stressors showed significant multivariate associations with burnout and smoking. Among the stressors were: being contacted outside work hours about patients, inadequate rest breaks, many patients/shifts, difficulty taking time off, insufficient pay, frequently listening to emotionally disturbing accounts, interruptions, increased workload, time pressure, and responsibility. Heavy patient burden/time pressure was most often cited as the hardest part of work in CORC. Increased employment of staff was the most frequently suggested workplace modification. Integrative assessment reveals that increased staff could ameliorate many work stressors associated with burnout and smoking in this cohort.

Conclusions

Working in CORC is an extra burden. In crisis situations such as the COVID pandemic, more staff is needed. Lowering the total job stressor load is vital.
Apolipoprotein E Recognizes Alzheimer's Disease Associated 3‐O Sulfation of Heparan Sulfate
Authors: Mah Dylan , Zhu Yanan , Su Guowei , Zhao Jing , Canning Ashely , Gibson James , Song Xuehong , Stancanelli Eduardo , Xu Yongmei , Zhang Fuming , Linhardt Robert J. , Liu Jian , Wang Lianchun , Wang Chunyu
Published: April 2023

Apolipoprotein E (ApoE)’s ϵ4 alle is the most important genetic risk factor for late onset Alzheimer's Disease (AD). Cell‐surface heparan sulfate (HS) is a cofactor for ApoE/LRP1 interaction and the prion‐like spread of tau pathology between cells. 3‐O‐sulfo (3‐O‐S) modification of HS has been linked to AD through its interaction with tau, and enhanced levels of 3‐O‐sulfated HS and 3‐O‐sulfotransferases in the AD brain. In this study, we characterized ApoE/HS interactions in wildtype ApoE3, AD‐linked ApoE4, and AD‐protective ApoE2 and ApoE3‐Christchurch. Glycan microarray and SPR assays revealed that all ApoE isoforms recognized 3‐O‐S. NMR titration localized ApoE/3‐O‐S binding to the vicinity of the canonical HS binding motif. In cells, the knockout of HS3ST1‐a major 3‐O sulfotransferase‐reduced cell surface binding and uptake of ApoE. 3‐O‐S is thus recognized by both tau and ApoE, suggesting that the interplay between 3‐O‐sulfated HS, tau and ApoE isoforms may modulate AD risk.
Chemically Fueled Autonomous Sol→Gel→Sol→Gel→Sol Transitions
Authors: Hermans Thomas M. , Singh Nishant
Published: April 2023

Complex non‐equilibrium phase behaviors are a hallmark of natural self‐assembling systems. Here we show how intricate phase transitions can be achieved through a chemically fueled reaction cycle to yield autonomous sol→gel→sol→gel→sol transitions. A relay of chemical transformations based on thiazinane metathesis leads to two consecutive transient gelations in a closed system. Within seconds of fuel addition to deactivated thiazinane monomers, an imine‐based hydrogel forms that consists of fibrillar microspheres. This gel quickly loses its mechanical strength and forms a solution, from which a second aldehyde‐based gel nucleates and remains stable for over one day. Overall, our reaction cycle gives rise to two consecutive re‐entrant phase transitions without any experimental intervention.
A Strong‐Acid‐Resistant [Th6] Cluster‐Based Framework for Effectively and Size‐Selectively Catalyzing Reductive Amination of Aldehydes with N,N‐Dimethylformamide
Authors: Tian Xue‐Rui , Jiang Zhi‐Yu , Hou Sheng‐Li , Hu Han‐Shi , Li Jun , Zhao Bin
Published: April 2023

Utilization of N,N‐dimethylformamide (DMF) as an amine source and reductant for synthesizing tertiary amines is a promising way to replace the substrates formaldehyde and dimethylamine, and it is desirable to seek porous acid‐resistant catalysts for heterogeneous catalysis of this reaction. Herein, a robust metal–organic framework (MOF) {[Th6O4(OH)4(H2O)6(BCP)3]⋅10 DMF}n (1) containing stacked nanocages with a diameter of 1.55 nm was constructed. Compound 1 can maintain its single‐crystal structure even kept in air at 400 °C for 3 h, and in DMF or water at 200 °C for 7 days. Density functional theory (DFT) calculations suggested that the high interaction energy between the [Th6O4(OH)4(H2O)6]12+ clusters and ligands was responsible for the excellent stability of 1. Catalytic investigations revealed that 1 can effectively and size‐selectively catalyze the reductive amination of aldehydes with DMF, and it can be reused at least five times without obvious loss in catalytic activity.
Inducing Covalent Atomic Interaction in Intermetallic Pt Alloy Nanocatalysts for High‐Performance Fuel Cells
Authors: Liu Xuan , Zhao Zhonglong , Liang Jiashun , Li Shenzhou , Lu Gang , Priest Cameron , Wang Tanyuan , Han Jiantao , Wu Gang , Wang Xiaoming , Huang Yunhui , Li Qing
Published: April 2023

The harsh working environments of proton exchange membrane fuel cells (PEMFCs) pose huge challenges to the stability of Pt‐based alloy catalysts. The widespread presence of metallic bonds with significantly delocalized electron distribution often lead to component segregation and rapid performance decay. Here we report L10−Pt2CuGa intermetallic nanoparticles with a unique covalent atomic interaction between Pt−Ga as high‐performance PEMFC cathode catalysts. The L10−Pt2CuGa/C catalyst shows superb oxygen reduction reaction (ORR) activity and stability in fuel cell cathode (mass activity=0.57 A mgPt−1 at 0.9 V, peak power density=2.60/1.24 W cm−2 in H2‐O2/air, 28 mV voltage loss at 0.8 A cm−2 after 30 000 cycles). Theoretical calculations reveal the optimized adsorption of oxygen intermediates via the formed biaxial strain on L10−Pt2CuGa surface, and the durability enhancement stems from the stronger Pt−M bonds than those in L11−PtCu resulted from Pt−Ga covalent interactions.
Co0−Coδ+ Interface Double‐Site‐Mediated C−C Coupling for the Photothermal Conversion of CO2 into Light Olefins
Authors: Ning Shangbo , Ou Honghui , Li Yaguang , Lv Cuncai , Wang Shufang , Wang Dingsheng , Ye Jinhua
Published: April 2023

Solar‐driven CO2 hydrogenation into multi‐carbon products is a highly desirable, but challenging reaction. The bottleneck of this reaction lies in the C−C coupling of C1 intermediates. Herein, we construct the C−C coupling centre for C1 intermediates via the in situ formation of Co0−Coδ+ interface double sites on MgAl2O4 (Co−CoOx/MAO). Our experimental and theoretical prediction results confirmed the effective adsorption and activation of CO2 by the Co0 site to produce C1 intermediates, while the introduction of the electron‐deficient state of Coδ+ can effectively reduce the energy barrier of the key CHCH* intermediates. Consequently, Co−CoOx/MAO exhibited a high C2–4 hydrocarbons production rate of 1303 μmol g−1 h−1; the total organic carbon selectivity of C2–4 hydrocarbons is 62.5 % under light irradiation with a high ratio (≈11) of olefin to paraffin. This study provides a new approach toward the design of photocatalysts used for CO2 conversion into C2+ products.
Chemo‐, Stereo‐ and Regioselective Fluoroallylation/Annulation of Hydrazones with gem‐Difluorocyclopropanes via Tunable Palladium/NHC Catalysis
Authors: Qian Huijun , Nguyen Hieu D. , Lv Leiyang , Chen Shuming , Li Zhiping
Published: April 2023

Defluorinative manipulation of polyfluorinated molecules has shown great promise due to its granting of synthetic versatility to inert C−F bonds. The development of chemo‐, stereo‐ and regioselective strategies to realize highly efficient formation of either the linear/branched or E/Z products from gem‐difluorocyclopropanes (gem‐F2CPs) is a challenging task. Herein, we have realized palladium/NHC‐catalyzed fluoroallylation/annulation of hydrazones with gem‐F2CPs that incorporate the hydrazone N2 moiety into the products. The thermodynamically unstable fluorinated E‐allylation products with aryl ketone hydrazones were obtained for the first time, while the di‐alkyl ketone hydrazones yielded the monofluorinated products with branched selectivity under similar reaction conditions. With aldehyde hydrazones, two kinds of pyrazoles were obtained via a defluorinative allylation/annulation cascade, in which different carbon atoms of gem‐F2CPs could be incorporated into the pyrazole rings regiospecifically. DFT calculations revealed that the divergent selectivity was kinetically controlled and the final C−C bond formation proceeded through a 7‐membered TS.
Discovery of the Lanthipeptide Curvocidin and Structural Insights into its Trifunctional Synthetase CuvL
Authors: Sigurdsson Arnar , Martins Berta M. , Düttmann Simon A. , Jasyk Martin , Dimos‐Röhl Benjamin , Schöpf Felix , Gemander Manuel , Knittel Caroline H. , Schnegotzki Romina , Schmid Bianca , Kosol Simone , Pommerening Lea , Gonzáles‐Viegaz María , Seidel Maria , Hügelland Manuela , Leimkühler Silke , Dobbek Holger , Mainz Andi , Süssmuth Roderich D.
Published: April 2023

Lanthipeptides are ribosomally‐synthesized natural products from bacteria featuring stable thioether‐crosslinks and various bioactivities. Herein, we report on a new clade of tricyclic class‐IV lanthipeptides with curvocidin from Thermomonospora curvata as its first representative. We obtained crystal structures of the corresponding lanthipeptide synthetase CuvL that showed a circular arrangement of its kinase, lyase and cyclase domains, forming a central reaction chamber for the iterative substrate processing involving nine catalytic steps. The combination of experimental data and artificial intelligence‐based structural models identified the N‐terminal subdomain of the kinase domain as the primary site of substrate recruitment. The ribosomal precursor peptide of curvocidin employs an amphipathic α‐helix in its leader region as an anchor to CuvL, while its substrate core shuttles within the central reaction chamber. Our study thus reveals general principles of domain organization and substrate recruitment of class‐IV and class‐III lanthipeptide synthetases.
meta‐Selective C−H Functionalization of Pyridines
Authors: Cao Hui , Cheng Qiang , Studer Armido
Published: April 2023

The pyridine moiety is an important core structure for a variety of drugs, agrochemicals, catalysts, and functional materials. Direct functionalization of C−H bonds in pyridines is a straightforward approach to access valuable substituted pyridines. Compared to the direct ortho‐ and para‐functionalization, meta‐selective pyridine C−H functionalization is far more challenging due to the inherent electronic properties of the pyridine entity. This review summarizes currently available methods for pyridine meta‐C−H functionalization using a directing group, non‐directed metalation, and temporary dearomatization strategies. Recent advances in ligand control and temporary dearomatization are highlighted. We analyze the advantages as well as limitations of current techniques and hope to inspire further developments in this important area.
Rapid chemical characterization of Danggui Buxue decoction using processed Astragali Radix and Angelicae Sinensis Radix based on diagnostic ion and molecular network
Authors: Cui Xiaojing , Qin Xuemei , Du Guanhua , Liu Yuetao
Published: April 2023

Danggui Buxue decoction (DBD), a classic prescription of traditional Chinese medicine (TCM) for invigorating qi and generating blood, contains honey‐processed Astragali Radix (HAR) and wine‐processed Angelicae Sinensis Radix (WDG) in its original prescription. In this study, the compositions of DBD, WDG, and HAR were characterized using ultra‐high‐performance liquid chromatography coupled with the quadrupole‐time‐of‐flight tandem mass spectrometry technique in combination with molecular network and diagnostic ion strategies. Finally, 200 compounds were identified in DBD, 114 compounds were identified in WDG, and 180 compounds were identified in HAR; there were 48 common compounds in total. The results demonstrated that compatibility led to changes in the chemical composition of TCM, and the qualitative method used in this study provided an effective data processing strategy for the characterization of components and the database for the study of the compounding mechanism of TCM.
Four New Polyhydroxy Cyclohexanes from the Stems of Fissistigma tientangense
Authors: Wu Mei‐Zhu , Chen Ming‐Chang , Zhang Xiao‐Zheng , Sun Chen , Chen Guang‐Ying , Yang Zi‐Han , Zheng Cai‐Juan , Luo You‐Ping , Zhou Xue‐Ming
Published: April 2023

Four undescribed polyhydroxy cyclohexanes, fissoxhydrylenes A–D (1–4), together with two known biogenetically related polyhydroxy cyclohexanes (5 and 6) were isolated from the stems of Fissistigma tientangense Tsiang et P. T. Li. Their structures were elucidated by detailed analysis of NMR, HR‐ESI‐MS, IR, UV and Optical rotations data. The absolute configuration of 1 was confirmed by X‐ray crystallographic. The absolute configurations of 2–4 were confirmed by chemical reaction and optical rotations. Compound 4 represent the first example of a no substituent polyhydroxy cyclohexanes from natural products. All isolated compounds were evaluated for their anti‐inflammatory activities against the lipopolysaccharide‐induced nitric oxide (NO) production in mouse macrophage RAW 264.7 cells in vitro. Compounds 3 and 4 showed inhibitory activities with the IC50 values of 16.63±0.06 μM and 14.38±0.08 μM, respectively.
Factors Influencing the Chemoselectivity of Pd(OAc)2‐Catalyzed Cyclization Reactions Involving 1,6‐Enynes as a Substrate and PhI(OAc)2 as a Reagent
Authors: Shiri Farshad , Ariafard Alireza
Published: April 2023

It is well documented in the literature that 1,6‐enynes are cyclized using PhI(OAc)2 (PIDA) in the presence of Pd(OAc)2 as a catalyst to yield cyclopropyl ketones. In contrast, it has been reported that when 1,6‐enynes are substituted by a hydroxy group at the α‐position to the alkyne, the chemoselectivity of the cyclization reaction is altered, and polycyclic oxa‐heterocycles are formed. This suggests that the hydroxy substituent plays a crucial role in changing the mechanism of the reaction. The aim of this study is to use density functional theory (DFT) calculations at the SMD/M06‐D3/def2TZVP//SMD/M06/SDD,6‐31G(d) level of theory to shed light on the reason for this change by investigating the detailed mechanistic aspects of these transformations. This study demonstrates that the electronic nature of the Pd catalyst changes from π‐philicity to oxophilicity during the catalytic cycle, and this change plays an essential role in controlling the chemoselectivity of the cyclization reactions. In addition, it was found that (1) the hypervalent iodine reagent PIDA serves not only as an oxidant for the oxidation of Pd(II) to Pd(IV), but also as a nucleophile that drives the acetoxypalladation step of the reaction, (2) the oxidation of Pd(II) to Pd(IV) by the iodonium ion [PhIOAc]+ occurs via an interesting mechanism involving coordination of [PhIOAc]+ to the Pd(II) centre, followed by a twist in the hypervalent iodine, and (3) Pd π‐complexes are not very susceptible to oxidation. (4) A Pd(II) complex can be six coordinate if the Pd centre is partially oxidized.
Esterase Specific Fluorescent Probe: Mechanistic Understanding Using QM/MM Calculation and Cell States Discrimination
Authors: Yadav Rashmi , Munan Subrata , Kardam Vandana , Dutta Dubey Kshatresh , Samanta Animesh
Published: April 2023

Esterases enzymes regulate the body's homeostasis by catalyzing the hydrolysis of various esters. These are also involved in protein metabolism, detoxification, and signal transmission. Most importantly, esterase plays a significant role in cell viability and cytotoxicity assays. Hence, developing an efficient chemical probe is essential for monitoring the esterase activity. Several fluorescent probes for esterase have also been reported targeting cytosol and lysosomes. However, the ability to create efficient probes is constrained due to a lack of understanding of the esterase‘s active site for hydrolyzing the substrate. In addition, the fluorescent turn‐on may limit efficient monitoring. Herein, we have developed a unique fluorescent probe, PM‐OAc, to monitor mitochondrial esterase enzyme activity ratiometrically. This probe exhibited a bathochromic wavelength shift with esterase enzyme in alkaline pH (pH∼8.0) due to an intramolecular charge transfer (ICT) process. The phenomenon is well supported by TD‐DFT calculation. Moreover, the substrate (PM‐OAc) binding at the active site of esterase and its catalytic mechanism to hydrolyze the ester bond are elucidated by molecular dynamics (MD) simulation and QM/MM (Quantum mechanics/molecular mechanics) calculations, respectively. Fluorescent image‐based analysis of the cellular environment reveals that our probe can distinguish between live and dead cells based on esterase enzyme activity.
Photoredox Synthesis of Thio‐Functionalized Cyclic Ethers Using N‐Sulfenyl Phthalimides as a Thiyl‐Radical Precursor
Authors: Lu Maojian , Liang Rong‐Bin , Zhu Can‐Ming , Tong Qing‐Xiao , Zhong Jian‐Ji
Published: April 2023

Comprehensive Summary

A visible‐light mediated exclusively regioselective synthesis of 2,2‐disubstituted thio‐functionalized tetrahydrofurans, tetrahydro‐ pyrans and oxepanes has been described through an operationally simple and mild photoredox protocol. Thiyl radical generated from N‐phenylsulfenyl phthalimide by photoredox catalysis was proven to be the key reactive intermediate in this reaction.
Cattle preference in Paspalum atratum and its relationship with morphological and anatomical leaf characteristics
Authors: Marcón Florencia , Di Lorenzo Elio L. , Peichoto Myriam C. , Acuña Carlos A.
Published: April 2023

New atra paspalum (Paspalum atratum Swallen) accessions were found to be differentially grazed by cattle, without differences in herbage accumulation and nutritive value. This study aimed to evaluate cattle preference, morphological and anatomical leaf traits, and their relationships at four sampling events. Five new atra paspalum accessions and the cultivar Cambá were used. The experimental unit was a 2 m × 2 m plot. Treatments were replicated four times in a completely randomized design. Cattle preference was determined in spring (December 2016 and 2017), summer (March 2017), and autumn (May 2017) using six steers Bos spp. that grazed the plots for 4 h on two consecutive days. Plant height, leaf‐blade length, leaf‐blade width, and the proportions of five leaf tissues at three leaf regions were measured at each date. The proportion of the leaf that is curved was measured in December 2017. Cattle preference was variable among accessions and sampling events. Some accessions were shorter, with shorter and more flexible leaves than Cambá (p < 0.05). The proportion of lignified tissues was greater during the spring (2016 and 2017) and summer (7%–23%) than in the autumn. One accession had the lowest proportion of lignified tissue in the warm season (8%–12%) but the highest during the fall (around 15%). The same accession had the fewest primary vascular bundles in the warm season. Cattle preference was negatively correlated with the proportion of lignified tissues, the number of primary vascular bundles, plant height, and leaf‐blade length. Cattle preference was affected by the growing season and reduced by greater presence of leaf structural tissue.
Sustainability reporting in Africa: A systematic review and agenda for future research
Authors: Igwe Monday Nweke , Khatib Saleh F. A. , Bazhair Ayman Hassan
Published: April 2023

This study provides a comprehensive systematic review of the sustainability reporting research focused on Africa. Using a systematic literature review approach, we synthesized 179 high‐quality journal articles obtained from the Scopus database. The study revealed that the extent and quality of SDGs and sustainability reporting in Africa are still very low and unsatisfactory. Also, we found that the existing studies mainly concentrated on the determinants of sustainability reporting, while limited research addressed the outcomes and sustainability assurance. Furthermore, the review indicates that firms in Africa predominantly focused on reporting their economic and social impacts while paying less attention to environmental protection. The study contributes to knowledge by providing an up‐to‐date and comprehensive review of sustainability reporting studies from important research contexts such as Africa. In doing so, we offer a more nuanced understanding of sustainability research in the region. We equally identified inconsistencies, gaps, and opportunities for future research.
Organic Redox Targeting Flow Battery Utilizing a Hydrophilic Polymer and Its In‐Operando Characterization via State‐of‐Charge Monitoring of The Redox Mediator
Authors: Schröter Erik , Stolze Christian , Meyer Jakob , Hager Martin D. , Schubert Ulrich S.
Published: April 2023

The hydrophilic poly(2,2,6,6‐tetramethylpiperdinyloxy‐4‐yl‐methacrylamide) (PTMAm) was utilized as redox target material in an aqueous organic redox targeting flow battery (RTFB). This polymer is processed into granules, which contain a conductive agent and an alginate binder. By this, a hydrophilic, yet water‐insoluble redox target can be obtained. The target was combined with the redox mediator molecule N,N,N‐trimethyl‐2‐oxo‐2‐[(2,2,6,6‐tetramethylpiperidin‐4‐yloxyl)amino]ethan‐1‐ammonium chloride (TEMPOAmide), that has been reported earlier as flow battery active material. This target/mediator combination has been characterized electrochemically and flow battery testing has been done. Furthermore, in‐operando characterization of the redox target via electrolyte state‐of‐charge (SOC) monitoring has been performed for the first time. The approach provides estimates for the redox target's SOC changes during cycling. In addition, a figure of merit – the “redox targetivity” – is proposed, which provides insights into the efficiency of the targeting reaction and supports the future optimization of materials, cell designs, and operational parameters for RTFBs.
Continuous Flow Hydrogenation of Lignin‐model Aromatic Compounds over Carbon‐supported Noble Metals
Authors: Polidoro Daniele , Selva Maurizio , Luque Rafael
Published: April 2023

An efficient continuous‐flow (CF) protocol was designed for the hydrogenation of lignin‐derived aromatics to the corresponding cycloalkanes derivatives. A parametric analysis of the reaction was carried out by tuning the temperature, the H2 pressure and the flow rate, and using diphenyl ether (DPE) as a model substrate, commercial Ru/C as a catalyst, and isopropanol as a solvent: at 25 °C, 50 bar H2, and a flow rate of 0.1 mL min−1, dicyclohexyl ether was achieved in an 86 % selectivity, at quantitative conversion. By‐products from the competitive C−O bond cleavage of DPE, cyclohexanol and cyclohexane, did not exceed 14 % in total. Remarkably, prolonged experiments demonstrated an excellent stability of the catalyst whose performance was unaltered for up to 420 min of time‐of‐stream. A substrate scope evaluation proved that under the same conditions used for DPE, a variety of substrates including alkoxy‐, allyl‐, and carbonyl‐functionalized phenols, biphenyl, aryl benzyl‐ and phenethyl ethers (10 examples) yielded the ring‐hydrogenated products with selectivity up to 99 % at complete conversion.
Morphologies and potential roles of telocytes in nervous tissue
Authors: Zhang Xu , Lu Ping , Shen Xiaorong
Published: April 2023

Structurally similar cells have been found and termed telocytes (TCs) since the first characterisation of interstitial Cajal‐like cells in 1911. TCs are a novel and peculiar interstitial cell type with a small cellular body, markedly long cell processes named telopodes and a wide distribution in numerous tissues throughout the body. Besides specific morphological characteristics and immunohistochemical profiles, TCs build three‐dimensional mixed networks through homocellular (connection to each other) and/or heterocellular contacts (connection with other cell types), interaction with extracellular matrix and their vicinity to nerve endings, and thus might play, as part of an integrated system, roles in maintaining organ/tissue function. In this mini‐review, we summarise physical properties, general characteristics and distribution of TCs in diverse organs and tissues, focusing on their potential functions in nervous tissue and current challenges in investigating TCs as a distinct cell type.
Intermolecular Acid–Base‐Pairs Containing Poly (p‐Terphenyl‐co‐Isatin Piperidinium) for High Temperature Proton Exchange Membrane Fuel Cells
Authors: Hao Xiaofeng , Li Zhen , Xiao Min , Huang Zhiheng , Han Dongmei , Huang Sheng , Liu Wei , Wang Shuanjin , Meng Yuezhong
Published: April 2023

How to optimize and regulate the distribution of phosphoric acid in matrix, and pursuing the improved electrochemical performance and service lifetime of high temperature proton exchange membrane (HT‐PEMs) fuel cell are significant challenges. Herein, bifunctional poly (p‐terphenyl‐co‐isatin piperidinium) copolymer with tethered phosphonic acid (t‐PA) and intrinsic tertiary amine base groups are firstly prepared and investigated as HT‐PEMs. The distinctive architecture of the copolymer provides a well‐designed platform for rapid proton transport. Protons not only transports through the hydrogen bond network formed by the adsorbed free phosphoric acid (f‐PA) anchored by the tertiary amine base groups, but also rely upon the proton channel constructed by the ionic cluster formed by the t‐PA aggregation. Thorough the design of the structure, the bifunctional copolymers with lower PA uptake level (<100%) display prominent proton conductivities and peak power densities (99 mS cm−1, 812 mW cm−2 at 160 °C), along with lower PA leaching and higher voltage stability, which is a top leading result in disclosed literature. The results demonstrate that the design of intermolecular acid–base‐pairs can improve the proton conductivity without sacrificing the intrinsic chemical stability or mechanical property of the thin membrane, realizing win‐win demands between the mechanical robustness and electrochemical properties of HT‐PEMs.
Portable smartphone‐based microfluidic electrochemical immunosensor for ultrasensitive detection of alpha‐fetoprotein in human serum
Authors: Shen Yanyun , Lu Wenhui , Fu Tengfei , Zhang Keying , Zhuo Xin , Wang Hongyan , Liu Chao , Xie Xusheng , Zhang Qing , Ma Shangshang
Published: April 2023

Rapid and accurate tracing of biomarkers is essential for early detecting and diagnosing of cancer. Therefore, a valid and convenient strategy needs to be developed for efficient monitoring of cancer biomarkers. Herein, we constructed a portable microfluidic electrochemical immunosensor based on three‐dimensional reduced graphene oxide (3D rGO) doped with gold nanoparticles (Au NPs) for ultrasensitive determination of alpha‐fetoprotein (AFP). The designed microfluidic chip, with the advantages of small injection volume, detachable structure and high integration, was fabricated by 3D printing, which only needed 9 μL of reagent to realize the high sensitivity detection. In addition, the 3D Au NPs‐rGO composites with high specific surface area and electrons transfer capacity can effectively increase electroactive sites and enhance electrochemical signals. Benefiting from these features, the 3D Au NPs‐rGO microfluidic electrochemical immunochip showed a wide detection range between 0.1 pg/mL–200 ng/mL and a best detection limit of 0.045 pg/mL with the high sensitivity of 175.008 μA (ng/mL)−1 cm−2. Meanwhile, the proposed immunosensor exhibited reliable AFP detection in human serum samples, which demonstrated that this portable smartphone‐based microfluidic electrochemical immunosensor hold great promises in clinical detection and huge potential in personalized healthcare.
A Novel Population of Slow Magnetosonic Waves and a Method for the Observation of the Roots of Plasma Bubbles in the Lower Ionosphere
Authors: Bennett Charles Lougheed
Published: April 2023

Using data from the Van Allen Probe and Swarm-Bravo satellites, evidence
for a persistent population of slow magnetosonic waves in the ionosphere
is presented. Dispersion relations from two-fluid analyses of waves in
warm plasma are used to interpret and explicate these observations.
These waves appear to be continuously present and globally distributed.
Their amplitudes systematically decrease with increasing altitude. The
amplitudes are also correlated with longitude in a manner consistent
with the global distribution of lightning strikes. Evidence for narrow
resonances in the Swarm data consistent with doppler shifted Schumann
resonance frequencies is presented. In addition, nearly dispersionless
fast magnetosonic waves are sometimes also seen. A new method for the
analysis of these waves suggests they show the existence of “foamy”
plasma bubble “roots” at the base of the ionosphere.
In Vitro–In Vivo Extrapolation of Hepatic Biotransformation Data for Fish. III. An In-depth Case Study with Pyrene
Authors: Nichols John W. , Fitzsimmons Patrick N. , Hoffman Alex D. , Wong Kameron
Published: April 2023

Computational models that predict chemical bioaccumulation in fish generally account for biotransformation using an apparent first-order whole-body rate constant (kB; d–1). The use of such models requires, therefore, that methods exist for estimating kB, ideally without the need to expose live animals. One promising approach for estimating kB involves the extrapolation of measured in vitro intrinsic clearance (CLIN VITRO,INT) to the whole animal (in vitro–in vivo extrapolation, [IVIVE]). To date, however, the accuracy of such predictions has been difficult to assess due to uncertainties associated with one or more extrapolation factors and/or a mismatch between fish used to generate in vitro data and those used to conduct in vivo exposures. In the present study we employed a combined in vitro and in vivo experimental approach to evaluate the IVIVE procedure using pyrene (PYR) as a model chemical. To the extent possible, measured rates of CLIN VITRO,INT were extrapolated to estimates of kB using extrapolation factors based on measured values. In vitro material (liver S9 fraction) was obtained from fish exposed to PYR in a controlled bioconcentration study protocol. Fish from the same study were then used to estimate in vivo kB values from an analysis of chemical depuration data. Averaged across four study groups, kB values estimated by IVIVE underestimated those determined from in vivo data by 2.6-fold. This difference corresponds to a 4.1-fold underestimation of true in vivo intrinsic clearance, assuming the liver is the only site of biotransformation. These findings are consistent with previous work performed using mammals and have important implications for use of measured CLIN VITRO,INT values in bioaccumulation assessments with fish. Environ Toxicol Chem 2023;42:1501–1515. Published 2023. This article is a U.S. Government work and is in the public domain in the USA.
Electricity price forecasting using hybrid deep learned networks
Authors: N. Krishna Prakash , Singh Jai Govind
Published: April 2023

This paper presents a novel hybrid model integrating maximal overlap discrete wavelet transform (MODWT) denoising and empirical mode decomposition (EMD) with sequence‐to‐sequence (seq2seq) long short‐term memory (LSTM) neural networks for day‐ahead electricity price forecasting. The nonstationary and nonlinear time series electricity price data are first denoised using MODWT. The resulting signal is decomposed into several intrinsic mode functions (IMF) with different resolutions by EMD. The extracted IMF is then introduced into seq2seq LSTM to obtain an aggregated predicted value for electricity price. The proposed method is examined using the Nord pool Elspot energy market data. Empirical results show that the proposed model outperformed the other forecasting models like LSTM and stacked LSTM. The performance measures indicate that data denoising can significantly improve the prediction stability and the generalization ability of the LSTM model.
Trading around the clock: Revisit volatility spillover between crude oil and equity markets in different trading sessions
Authors: Hao Jing , He Feng , Ma Feng , Fu Tong
Published: April 2023

We investigate the volatility spillover between the crude oil (West Texas Intermediate) and G7 countries' equity markets with high‐frequency data. Considering the trading period difference among different countries, the volatility spillover of oil market intraday and overnight sessions is studied with G7 countries, respectively. The empirical findings suggest that the US stock market dominates intraday volatility spillover to the oil market, while the European and Asian stock markets dominate overnight spillovers. The asymmetric spillover result shows that stock markets mainly spillover bad volatility to the oil market in the intraday trading session, and spillover good volatility to the oil market in the overnight trading session. Our results provide empirical evidence that crude oil market overnight trading information is also important for understanding information diffusion and volatility forecasting.
A Late Palaeozoic disconformity in the Moqinwula area: Insights into the tectonic evolution and basement nature of the Junggar Block, NW China
Authors: Wang Wei , Wang Guo‐Can , Zhang Pan , Zhang Meng , Wang An , Chen Yue , Sotiriou Paul
Published: April 2023

The recognition of unconformities is important for stratigraphic subdivision and correlation and for determining the timing of tectonic activity and the ocean‐continent transition process. Here, we have identified a Late Palaeozoic disconformity in the Moqinwula area of the northern Junggar Block, NW China. Integrated field relationship observations and sedimentological, biostratigraphical, geochemical and detrital zircon geochronological data, suggest that the underlying Hongliugou Formation is of Devonian age and was deposited in a passive continental margin setting. The overlying Tamugang Formation formed in the Early Carboniferous and was deposited in a foreland basin setting. Integrating the published data and our new work, we suggest a new tectonic evolution model related to the Karamaili ocean‐continent transition process. During the Early Devonian, northward subduction of the Karamaili Ocean plate beneath the East Junggar Belt formed the Yemaquan arc. At this time, a passive margin sequence was deposited on the northern Junggar Block. During the Early Carboniferous, the closure of the Karamaili Ocean resulted from the collision between the Junggar Block and the East Junggar Belt. Foreland basins subsequently developed, forming an extensive unconformity in the accretionary wedge to the north and a disconformity in the relatively rigid and stable Junggar Block to the south. This significant difference in stratigraphic contact relationships confirms that regional convergence‐induced shortening deformation had no significant influence on the northern margin of the Junggar Block, suggesting the existence of a relatively rigid basement, probably an oceanic plateau, under the cover sediments of the Junggar Block.
Refractory florid cystic endosalpingiosis: A case report with 5 years follow up and literature review
Authors: Zhan Hong , Zhang Hongyun , Sun Jin , Wang Wenwen , Zhu Jiang , Huang Xiufeng
Published: April 2023

Endosalpingiosis is characterized by the presence of ectopic, benign glands with a fallopian tube‐like ciliated epithelium. Florid cystic endosalpingiosis (FCE) is a rare type of endosalpingiosis and presents with tumor‐like lesions. In general, FCE has no specific clinical features. In this case, extensive pelvic multiple Müllerian cysts were first observed and removed during the patient's second cesarean section. Lesions relapsed after a year. Therefore, the patient underwent total hysterectomy and bilateral salpingectomy; pathology revealed that the patient had FCE. According to imaging studies during the follow up, recurrent and progressive multiple pelvic and extra‐pelvic cysts were observed. The patient had no obvious symptoms, and the results of her laboratory tests were within normal limits. Ultrasound‐guided aspiration and lauromacrogol sclerotherapy were performed, and in the past year, the cysts have stabilized without progression. This is the first reported case of recurrent FCE after total hysterectomy and bilateral salpingectomy with a 5‐year follow up. A literature review and novel ideas for diagnosing and managing FCE based on this case are also presented.
The dual and emerging role of physical exercise‐induced TFEB activation in the protection against Alzheimer's disease
Authors: Morais Gustavo Paroschi , de Sousa Neto Ivo Vieira , Marafon Bruno Brieda , Ropelle Eduardo R. , Cintra Dennys E. , Pauli José R. , Silva Adelino S. R. da
Published: April 2023

The mechanisms of autophagy have been related to Alzheimer's disease (AD) pathogenesis by the endosomal‐lysosomal system, having a critical function in forming amyloid‐β (Aβ) plaques. Nevertheless, the exact mechanisms mediating disease pathogenesis remain unclear. The transcription factor EB (TFEB), a primary transcriptional autophagy regulator, improves gene expression, mediating lysosome function, autophagic flux, and autophagosome biogenesis. In this review, we present for the first time the hypothesis of how TFEB, autophagy, and mitochondrial function are interconnected in AD, providing a logical foundation for unraveling the critical role of chronic physical exercise in this process. Aerobic exercise training promotes Adiponectin Receptor 1 (AdipoR1)/AMP‐activated protein kinase (AMPK)/TFEB axis activation in the brain of the AD animal model, which contributes to alleviated Aβ deposition and neuronal apoptosis while improving cognitive function. Moreover, TFEB upregulates Peroxisome proliferator‐activated receptor gamma coactivator 1‐alpha (PGC‐1α) and nuclear factor erythroid 2‐related factor 2 (NRF‐2), improving mitochondrial biogenesis and redox status. In addition, tissue contraction activates calcineurin in skeletal muscle, which induces TFEB nuclear translocation, raising the hypothesis that the same would occur in the brain. Thus, a deep and comprehensive exploration of the TFEB could provide new directions and strategies for preventing AD. We conclude that chronic exercise can be an effective TFEB activator, inducing autophagy and mitochondrial biogenesis, representing a potential nonpharmacological strategy contributing to brain health.
MRI‐Based Breast Cancer Classification and Localization by Multiparametric Feature Extraction and Combination Using Deep Learning
Authors: Cong Chao , Li Xiaoguang , Zhang Chunlai , Zhang Jing , Sun Kaixiang , Liu Lianluyi , Ambale‐Venkatesh Bharath , Chen Xiao , Wang Yi
Published: April 2023

Background

Deep learning (DL) have been reported feasible in breast MRI. However, the effectiveness of DL method in mpMRI combinations for breast cancer detection has not been well investigated.

Purpose

To implement a DL method for breast cancer classification and detection using feature extraction and combination from multiple sequences.

Study Type

Retrospective.

Population

A total of 569 local cases as internal cohort (50.2 ± 11.2 years; 100% female), divided among training (218), validation (73) and testing (278); 125 cases from a public dataset as the external cohort (53.6 ± 11.5 years; 100% female).

Field Strength/Sequence

T1‐weighted imaging and dynamic contrast‐enhanced MRI (DCE‐MRI) with gradient echo sequences, T2‐weighted imaging (T2WI) with spin‐echo sequences, diffusion‐weighted imaging with single‐shot echo‐planar sequence and at 1.5‐T.

Assessment

A convolutional neural network and long short‐term memory cascaded network was implemented for lesion classification with histopathology as the ground truth for malignant and benign categories and contralateral breasts as healthy category in internal/external cohorts. BI‐RADS categories were assessed by three independent radiologists as comparison, and class activation map was employed for lesion localization in internal cohort. The classification and localization performances were assessed with DCE‐MRI and non‐DCE sequences, respectively.

Statistical Tests

Sensitivity, specificity, area under the curve (AUC), DeLong test, and Cohen's kappa for lesion classification. Sensitivity and mean squared error for localization. A P‐value <0.05 was considered statistically significant.

Results

With the optimized mpMRI combinations, the lesion classification achieved an AUC = 0.98/0.91, sensitivity = 0.96/0.83 in the internal/external cohorts, respectively. Without DCE‐MRI, the DL‐based method was superior to radiologists' readings (AUC 0.96 vs. 0.90). The lesion localization achieved sensitivities of 0.97/0.93 with DCE‐MRI/T2WI alone, respectively.

Data Conclusion

The DL method achieved high accuracy for lesion detection in the internal/external cohorts. The classification performance with a contrast agent‐free combination is comparable to DCE‐MRI alone and the radiologists' reading in AUC and sensitivity.

Evidence Level

3.

Technical Efficacy

Stage 2.
Chemical burns generated by chlorine gas
Authors: Norimatsu Yuta , Goto Taeko , Kogure Asako , Kuwano Yoshihiro
Published: April 2023

We present the case of a 40‐year‐old woman exposed for 4 h and 30 min to chlorine gas generated by mixing detergents containing hydrochloric acid and hypochlorous acid to commit suicide in the bathroom. Acute respiratory failure, chemical burns all over the face and a corneal erosion occurred. Despite skin chemical burns have not been reported after exposure to chlorine gas, this report suggests that chemical burns may occur due to prolonged exposure even at relatively low concentration of chlorine gas.
Temporal and spatial distribution of dorcas and slender‐horned gazelles in a Saharan habitat
Authors: Meliane Mohamed Khalil , Saidi Amira , Petretto Marie , Gilbert Tania , Nasri‐Ammar Karima
Published: April 2023

Saharan ungulates have suffered from poaching across their range leading to population declines. Low abundance and habitat inaccessibility have limited the availability of empirical data on desert ungulate ecology in the wild. Our objective was to evaluate temporal and spatial distribution, and home‐range sizes of wild dorcas gazelles (Gazella dorcas) and slender‐horned gazelles (Gazella leptoceros) under natural conditions using observations from 14,398 camera‐days collected between April 2019 and October 2021 in the 7,700‐ha fenced area of Jbil National Park (Jbil NP), Tunisia. We individually identified gazelles in Jbil NP using unique horn morphology. Both gazelle species exhibited nocturnal activity patterns in summer, but diurnal activity patterns dominated in winter. We also detected both species more frequently in the plains than in mountains. Water presence was influential in determining distribution only for dorcas gazelles. Minimum convex polygons (MCPs) were 2,062 ha for both the male and female of the most frequently detected dorcas gazelle pair and 1,527 ha for another solitary male. For slender‐horned gazelles, MCPs were 2,280 ha and 2,041 ha, respectively, for a male and a female detected in Jbil NP. The decline and rarity of gazelles in the Sahara Desert have limited the sample size of our observed populations. Our study provides hitherto unknown data on wild populations of rapidly declining gazelle species and contributes to ongoing conservation efforts.
dl‐Methionine‐Mediated Reversible Deactivation Radical Polymerization of Styrene and Methyl Methacrylate
Authors: Lv Hanyu , An Jiaqi , Li Fanfan , Zhang Yanwu
Published: April 2023

Reversible deactivation radical polymerization (RDRP) is a facile and highly efficient technique for the synthesis of well‐defined polymer with precise structure. dl‐Methionine (Met) as a RDRP control agent is described and assessed for RDRP of styrene (St) and methyl methacrylate (MMA) with AIBN as radical initiator at 75 °C, which enables excellent control of this polymerization. The addition of dl‐Methionine significantly decreased the dispersity (Đ) of the polymers for both monomers and first‐order linear kinetic plots of polymethyl methacrylate (PMMA) are observed in DMSO. Considering the heat resistance of dl‐Methionine, kinetic studies indicate that polymerization develops at a faster rate at higher reaction temperature (100 °C) with the same dl‐Methionine content. Well‐defined polymethyl methacrylate‐block‐polystyrene (PMMA‐block‐PSt) is successfully achieved by the chain extension reaction that demonstrates the high end fidelities of this polymerization approach. The system allows the use of dl‐Methionine, a rich source and easily synthesized agent, to mediate RDRP strategy.
miR‐132‐3p promotes heat stimulation‐induced esophageal squamous cell carcinoma tumorigenesis by targeting KCNK2
Authors: Wang Jing , Li Jiaqiong , Cheng Dan , Zhang Keke , Liu Wenting , Xue Qianqian , Du Ruijuan , Zhou Liting , Yeung Yiu To , Bai Ruihua , Huang Hui , Cui Jie , Xiang Pu , Zhi Yafei , Liu Kangdong , Li Xiang , Dong Zigang
Published: April 2023

Epidemiological evidence supports that consumption of high‐temperature food and beverages is an important risk factor for esophageal squamous cell carcinoma (ESCC); however, the underlying mechanism still remains unclear. Here, we established a series of animal models and found that drinking 65°C water can promote esophageal tumor progression from preneoplastic lesions to ESCC. RNA sequencing data showed that miR‐132‐3p was highly expressed in the heat stimulation group compared with controls. Further study verified that miR‐132‐3p were upregulated in human premalignant lesion tissues of the esophagus, ESCC tissues, and cells. Overexpression of miR‐132‐3p could promote ESCC cell proliferation and colony formation, whereas knockdown of miR‐132‐3p could inhibit ESCC progression in vitro and in vivo. Importantly, dual‐luciferase reporter assays showed that miR‐132‐3p could bind with the 3′‐untranslated region of KCNK2 and inhibit KCNK2 gene expression. Knockdown or overexpression of KCNK2 could promote or suppress ESCC progression in vitro. These data suggest that heat stimulation can promote ESCC progression and miR‐132‐3p mediated this process by directly targeting KCNK2.