bluuebunny/crossref_metadata_2025 huggingface dataset:
NR4A1 enhances MKP7 expression to diminish JNK activation induced by ROS or ER-stress in pancreatic β cells for surviving
Authors: Pu Ze-qing , Yu Tian-fu , Liu Dong , Jin Cheng-wen , Sadiq Esha , Qiao Xiaofei , Li Xiaojie , Chen Yuxuan , Zhang Jinsong , Tian Mingzhong , Li Siying , Zhao Ru-xing , Wang Xiang-dong
Published: June 2021

Under adverse conditions, such as sustained or chronic hyperglycemia or hyperlipidemia, ROS (reactive oxygen species) or/and ER-stress (endoplasmic reticulum stress) will be induced in pancreatic β cells. ROS or ER-stress damages β-cells even leads to apoptosis. Previously we found ROS or ER-stress resulted in JNK activation in β cells and overexpressing NR4A1 in MIN6 cells reduced JNK activation via modulating cbl-b expression and subsequent degrading the upstream JNK kinase (MKK4). To search other possible mechanisms, we found the mRNA level and protein level of MKP7 (a phosphatase for phospho-JNK) were dramatic reduced in pancreatic β cells in the islets from NR4A1 KO mice compared with that from wild type mice. To confirm what we found in animals, we applied pancreatic β cells (MIN6 cells) and found that the expression of MKP7 was increased in NR4A1-overexpression MIN6 cells. We further found that knocking down the expression of MKP7 increased the p-JNK level in pancreatic β cells upon treatment with TG or H2O2. After that, we figured out that NR4A1 did enhance the transactivation of the MKP7 promoter by physical association with two putative binding sites. In sum, NR4A1 attenuates JNK phosphorylation incurred by ER-stress or ROS partially via enhancing MKP7 expression, potentially decreases pancreatic β cell apoptosis induced by ROS or ER-stress. Our finding provides a clue for diabetes prevention.
Radiative properties of quantum emitters in boron nitride from excited state calculations and Bayesian analysis
Authors: Gao Shiyuan , Chen Hsiao-Yi , Bernardi Marco
Published: June 2021

Point defects in hexagonal boron nitride (hBN) have attracted growing attention as bright single-photon emitters. However, understanding of their atomic structure and radiative properties remains incomplete. Here we study the excited states and radiative lifetimes of over 20 native defects and carbon or oxygen impurities in hBN using ab initio density functional theory and GW plus Bethe-Salpeter equation calculations, generating a large data set of their emission energy, polarization and lifetime. We find a wide variability across quantum emitters, with exciton energies ranging from 0.3 to 4 eV and radiative lifetimes from ns to ms for different defect structures. Through a Bayesian statistical analysis, we identify various high-likelihood charge-neutral defect emitters, among which the native VNNBdefect is predicted to possess emission energy and radiative lifetime in agreement with experiments. Our work advances the microscopic understanding of hBN single-photon emitters and introduces a computational framework to characterize and identify quantum emitters in 2D materials.
Gapless quantum spin liquid in a honeycomb Γ magnet
Authors: Luo Qiang , Zhao Jize , Kee Hae-Young , Wang Xiaoqun
Published: June 2021

A family of spin–orbit coupled honeycomb Mott insulators offers a playground to search for quantum spin liquids (QSLs) via bond-dependent interactions. In candidate materials, a symmetric off-diagonal Γ term, close cousin of Kitaev interaction, has emerged as another source of frustration that is essential for complete understanding of these systems. However, the ground state of honeycomb Γ model remains elusive, with a suggested zigzag magnetic order. Here we attempt to resolve the puzzle by perturbing the Γ region with a staggered Heisenberg interaction which favours the zigzag ordering. Despite such favour, we find a wide disordered region inclusive of the Γ limit in the phase diagram. Further, this phase exhibits a vanishing energy gap, a collapse of excitation spectrum, and a logarithmic entanglement entropy scaling on long cylinders, indicating a gapless QSL. Other quantities such as plaquette-plaquette correlation are also discussed.
New evidence from exceptionally “well-preserved” specimens sheds light on the structure of the ammonite brachial crown
Authors: Smith C. P. A. , Landman N. H. , Bardin J. , Kruta I.
Published: June 2021

Ammonite soft body remains are rarely preserved. One of the biggest enigmas is the morphology of the ammonite brachial crown that has, up till now, never been recovered. Recently, mysterious hook-like structures have been reported in multiple specimens of Scaphitidae, a large family of heteromorph Late Cretaceous ammonites. A previous examination of these structures revealed that they belong to the ammonites. Their nature, however, remained elusive. Here, we exploit tomographic data to study their arrangement in space in order to clarify this matter. After using topological data analyses and comparing their morphology, number, and distribution to other known cephalopod structures, in both extant and extinct taxa, we conclude that these hook-like structures represent part of the brachial crown armature. Therefore, it appears that there are at least three independent evolutionary origins of hooks: in belemnoids, oegospids, and now in ammonites. Finally, we propose for the first time a hypothetical reconstruction of an ammonite brachial crown.
Deep denoising for multi-dimensional synchrotron X-ray tomography without high-quality reference data
Authors: Hendriksen Allard A. , Bührer Minna , Leone Laura , Merlini Marco , Vigano Nicola , Pelt Daniël M. , Marone Federica , di Michiel Marco , Batenburg K. Joost
Published: June 2021

Synchrotron X-ray tomography enables the examination of the internal structure of materials at submicron spatial resolution and subsecond temporal resolution. Unavoidable experimental constraints can impose dose and time limits on the measurements, introducing noise in the reconstructed images. Convolutional neural networks (CNNs) have emerged as a powerful tool to remove noise from reconstructed images. However, their training typically requires collecting a dataset of paired noisy and high-quality measurements, which is a major obstacle to their use in practice. To circumvent this problem, methods for CNN-based denoising have recently been proposed that require no separate training data beyond the already available noisy reconstructions. Among these, the Noise2Inverse method is specifically designed for tomography and related inverse problems. To date, applications of Noise2Inverse have only taken into account 2D spatial information. In this paper, we expand the application of Noise2Inverse in space, time, and spectrum-like domains. This development enhances applications to static and dynamic micro-tomography as well as X-ray diffraction tomography. Results on real-world datasets establish that Noise2Inverse is capable of accurate denoising and enables a substantial reduction in acquisition time while maintaining image quality.
Microarray analysis reveals ONC201 mediated differential mechanisms of CHOP gene regulation in metastatic and nonmetastatic colorectal cancer cells
Authors: Al Madhoun Ashraf , Haddad Dania , Al Tarrah Mustafa , Jacob Sindhu , Al-Ali Waleed , Nizam Rasheeba , Miranda Lavina , Al-Rashed Fatema , Sindhu Sardar , Ahmad Rasheed , Bitar Milad S. , Al-Mulla Fahd
Published: June 2021

The imipramine ONC201 has antiproliferative effects in several cancer cell types and activates integrated stress response pathway associated with the induction of Damage Inducible Transcript 3 (DDIT3, also known as C/EBP homologous protein or CHOP). We investigated the signaling pathways through which ONC201/CHOP crosstalk is regulated in ONC201-treated nonmetastatic and metastatic cancer cell lines (Dukes' type B colorectal adenocarcinoma nonmetastatic SW480 and metastatic LS-174T cells, respectively). Cell proliferation and apoptosis were evaluated by MTT assays and flow cytometry, gene expression was assessed by Affymetrix microarray, signaling pathway perturbations were assessed in silico, and key regulatory proteins were validated by Western blotting. Unlike LS-174T cells, SW480 cells were resistant to ONC201 treatment; Gene Ontology analysis of differentially expressed genes showed that cellular responsiveness to ONC201 treatment also differed substantially. In both ONC201-treated cell lines, CHOP expression was upregulated; however, its upstream regulatory mechanisms were perturbed. Although, PERK, ATF6 and IRE1 ER-stress pathways upregulated CHOP in both cell types, the Bak/Bax pathway regulated CHOP only LS-174T cells. Additionally, CHOP RNA splicing profiles varied between cell lines; these were further modified by ONC201 treatment. In conclusion, we delineated the signaling mechanisms by which CHOP expression is regulated in ONC201-treated non-metastatic and metastatic colorectal cell lines. The observed differences could be related to cellular plasticity and metabolic reprogramming, nevertheless, detailed mechanistic studies are required for further validations.
Changing trends in dialysis modalities utilization and mortality in children, adolescents and young adults with acute kidney injury, 2010–2017
Authors: Tain You-Lin , Kuo Hsiao-Ching , Hsu Chien-Ning
Published: June 2021

The aim of the study was to assess trends in the relative use of dialysis modalities in the hospital-based pediatric cohort and to determine risk factors associated with in-hospital morality among pediatric patients receiving dialysis for acute kidney injury (AKI). Patients aged < 20 years who received dialysis between 2010 and 2017 were identified from electronic health records databases of a Taiwan’s healthcare delivery system. The annual uses of intermittent hemodialysis (HD), continuous and automated peritoneal dialysis (PD) and continuous kidney replacement therapy (CKRT) were assessed using Cochran-Armitage Tests for trend. Among patients who received their first dialysis as inpatients for AKI, a multivariate logistic regression model was employed to assess mortality risks associated with dialysis modalities, patient demographics, complexity of baseline chronic disease, and healthcare service use during their hospital stays. Kidney dialysis was performed 37.9 per patient per year over the study period. Intermittent hemodialysis (HD) (73.3%) was the most frequently used dialysis modality. In the inpatient setting, the relative annual use of CKRT increased over the study period, while HD use concomitantly declined (P < 0.0001). The overall in-hospital mortality rate after dialysis for AKI was 33.6%, which remained steady over time (P = 0.2411). Patients aged < 2 years [adjusted odds ratio: (aOR) 3.36; 95% confidence interval (CI) 1.34–8.93] and greater vasoactive regimen use (aOR: 17.1; 95% CI: 5.3–55.21) were significantly associated with dialysis-related mortality. Overall treatment modality used for dialysis in pediatric patients increased slowly in the study period, and HD and CRKT modality uses largely evolved in the inpatient setting. Younger ages and use of more vasoactive medication regimens were independently associated with increased early mortality in patients on AKI-dialysis.
Research on automatic labeling of imbalanced texts of customer complaints based on text enhancement and layer-by-layer semantic matching
Authors: Tang Xiaobo , Mou Hao , Liu Jiangnan , Du Xin
Published: June 2021

Due to its potential impact on business efficiency, automated customer complaint labeling and classification are of great importance for management decision making and business applications. The majority of the current research on automated labeling uses large and well-balanced datasets. However, customer complaint labels are hierarchical in structure, with many labels at the lowest hierarchy level. Relying on lower-level labels leads to small and imbalanced samples, thus rendering the current automatic labeling practices inapplicable to customer complaints. This article proposes an automatic labeling model incorporating the BERT and word2vec methods. The model is validated on electric utility customer complaint data. Within the model, the BERT method serves to obtain shallow text tags. Furthermore, text enhancement is used to mitigate the problem of imbalanced samples that emerge when the number of labels is large. Finally, the word2vec model is utilized for deep text analysis. Experiments demonstrate the proposed model's efficiency in automating customer complaint labeling. Consequently, the proposed model supports enterprises in improving their service quality while simultaneously reducing labor costs.
Clinical implication of bactibilia in moderate to severe acute cholecystitis undergone cholecystostomy following cholecystectomy
Authors: Yoon Je Ho , Paik Kwang Yeol , Chung Hoo Young , Oh Ji Seon
Published: June 2021

There is little evidence of clinical outcome in using antibiotics during the perioperative phase of acute cholecystitis with bactibilia. The aim of current study is to examine the effect of bactibilia on patients with acute cholecystitis and their perioperative clinical outcome. We performed a retrospective cohort analysis of 128 patients who underwent cholecystectomy for acute cholecystitis with moderate and severe grade. Patients who were positive for bactibilia were compared to bactibilia-negative group in following categories: morbidity, duration of antimicrobial agent use, in-hospital course, and readmission rate. There was no difference in morbidity when patients with bactibilia (n = 70) were compared to those without (n = 58) after cholecystectomy. The duration of antibiotics use and clinical course were also similar in both groups. In severe grade AC group (n = 18), patients used antibiotics and were hospitalized for a significantly longer period of time than those in the moderate grade AC group. The morbidity including surgical site infection, and readmission rates were not significantly different in moderate and severe grade AC groups. In moderate and severe AC groups, bactibilia itself did not predict more complication and worse clinical course. Antibiotics may be safely discontinued within few days after cholecystectomy irrespective of bactibilia when cholecystectomy is successful.
Body dynamics of gait affect value-based decisions
Authors: Grießbach Eric , Incagli Francesca , Herbort Oliver , Cañal-Bruland Rouwen
Published: June 2021

Choosing among different options typically entails weighing their anticipated costs and benefits. Previous research has predominantly focused on situations, where the costs and benefits of choices are known before an action is effectuated. Yet many decisions in daily life are made on the fly, for instance, making a snack choice while walking through the grocery store. Notably, the costs of actions change dynamically while moving. Therefore, in this study we examined whether the concurrent action dynamics of gait form part of and affect value-based decisions. In three experiments, participants had to decide which lateral (left vs. right) target (associated with different rewards) they would go to, while they were already walking. Results showed that the target choice was biased by the alternating stepping behavior, even at the expense of receiving less reward. These findings provide evidence that whole-body action dynamics affect value-based decisions.
Peptide-guided JC polyomavirus-like particles specifically target bladder cancer cells for gene therapy
Authors: Lai Wei-Hong , Fang Chiung-Yao , Chou Ming-Chieh , Lin Mien-Chun , Shen Cheng-Huang , Chao Chun-Nun , Jou Yeong‐Chin , Chang Deching , Wang Meilin
Published: June 2021

The ultimate goal of gene delivery vectors is to establish specific and effective treatments for human diseases. We previously demonstrated that human JC polyomavirus (JCPyV) virus-like particles (VLPs) can package and deliver exogenous DNA into susceptible cells for gene expression. For tissue-specific targeting in this study, JCPyV VLPs were conjugated with a specific peptide for bladder cancer (SPB) that specifically binds to bladder cancer cells. The suicide gene thymidine kinase was packaged and delivered by SPB-conjugated VLPs (VLP-SPBs). Expression of the suicide gene was detected only in human bladder cancer cells and not in lung cancer or neuroblastoma cells susceptible to JCPyV VLP infection in vitro and in vivo, demonstrating the target specificity of VLP-SPBs. The gene transduction efficiency of VLP-SPBs was approximately 100 times greater than that of VLPs without the conjugated peptide. JCPyV VLPs can be specifically guided to target particular cell types when tagged with a ligand molecule that binds to a cell surface marker, thereby improving gene therapy.
Enhancement of protein thermostability by three consecutive mutations using loop-walking method and machine learning
Authors: Yoshida Kazunori , Kawai Shun , Fujitani Masaya , Koikeda Satoshi , Kato Ryuji , Ema Tadashi
Published: June 2021

We developed a method to improve protein thermostability, “loop-walking method”. Three consecutive positions in 12 loops of Burkholderia cepacia lipase were subjected to random mutagenesis to make 12 libraries. Screening allowed us to identify L7 as a hot-spot loop having an impact on thermostability, and the P233G/L234E/V235M mutant was found from 214 variants in the L7 library. Although a more excellent mutant might be discovered by screening all the 8000 P233X/L234X/V235X mutants, it was difficult to assay all of them. We therefore employed machine learning. Using thermostability data of the 214 mutants, a computational discrimination model was constructed to predict thermostability potentials. Among 7786 combinations ranked in silico, 20 promising candidates were selected and assayed. The P233D/L234P/V235S mutant retained 66% activity after heat treatment at 60 °C for 30 min, which was higher than those of the wild-type enzyme (5%) and the P233G/L234E/V235M mutant (35%).
Atomic force microscopy analysis of native infectious and inactivated SARS-CoV-2 virions
Authors: Lyonnais Sébastien , Hénaut Mathilde , Neyret Aymeric , Merida Peggy , Cazevieille Chantal , Gros Nathalie , Chable-Bessia Christine , Muriaux Delphine
Published: June 2021

SARS-CoV-2 is an enveloped virus responsible for the Coronavirus Disease 2019 (COVID-19) pandemic. Here, single viruses were analyzed by atomic force microscopy (AFM) operating directly in a level 3 biosafety (BSL3) facility, which appeared as a fast and powerful method to assess at the nanoscale level and in 3D infectious virus morphology in its native conformation, or upon inactivation treatments. AFM imaging reveals structurally intact infectious and inactivated SARS-CoV-2 upon low concentration of formaldehyde treatment. This protocol combining AFM and plaque assays allows the preparation of intact inactivated SARS-CoV-2 particles for safe use of samples out of level 3 laboratory to accelerate researches against the COVID-19 pandemic. Overall, we illustrate how adapted BSL3-AFM is a remarkable toolbox for rapid and direct virus analysis based on nanoscale morphology.
Establishment and assessment of an amplicon sequencing method targeting the 16S-ITS-23S rRNA operon for analysis of the equine gut microbiome
Authors: Kinoshita Yuta , Niwa Hidekazu , Uchida-Fujii Eri , Nukada Toshio
Published: June 2021

Microbial communities are commonly studied by using amplicon sequencing of part of the 16S rRNA gene. Sequencing of the full-length 16S rRNA gene can provide higher taxonomic resolution and accuracy. To obtain even higher taxonomic resolution, with as few false-positives as possible, we assessed a method using long amplicon sequencing targeting the rRNA operon combined with a CCMetagen pipeline. Taxonomic assignment had > 90% accuracy at the species level in a mock sample and at the family level in equine fecal samples, generating similar taxonomic composition as shotgun sequencing. The rRNA operon amplicon sequencing of equine fecal samples underestimated compositional percentages of bacterial strains containing unlinked rRNA genes by a fourth to a third, but unlinked rRNA genes had a limited effect on the overall results. The rRNA operon amplicon sequencing with the A519F + U2428R primer set was able to detect some kind of archaeal genomes such asMethanobacterialesandMethanomicrobiales, whereas full-length 16S rRNA with 27F + 1492R could not. Therefore, we conclude that amplicon sequencing targeting the rRNA operon captures more detailed variations of equine microbiota.
Fluorescent detection of target proteins via a molecularly imprinted hydrogel
Authors: Kubo Takuya , Watanabe Naoki , Ikari Seiji , Liu Chenchen , Kanao Eisuke , Naito Toyohiro , Sano Tomoharu , Otsuka Koji
Published: June 2021

A molecularly imprinted hydrogel with a PEG-fluorescent monomer was used for the selective detection of a target protein.
Heat conduction of electrons and phonons in thermal interface materials
Authors: Zhao Yunshan , Zeng Xiangliang , Ren Linlin , Xia Xinnian , Zeng Xiaoliang , Zhou Jun
Published: June 2021

Investigation on the thermal transport of heat carriers in TIMs will aid in promoting the advancement of TIMs with high performance.
Glutaredoxin1 knockout promotes high-fat diet-induced obesity in male mice but not in female ones
Authors: Zou Xiaoyu , Ahmad Muhammad Ijaz , Zhao Di , Zhang Min , Li Chunbao
Published: June 2021

Glrx1 deficiency aggravated high-fat-diet-induced hyperlipidemia, liver injury and oxidative stress. Diet altered the gut microbiota composition. The results provide a new insight into the susceptibilities to obesity between males and females.
Regulating the Bi NIR luminescence behaviours in fluorine and nitrogen co-doped germanate glasses
Authors: Chen Fuguang , Wang Yafei , Chen Weiwei , Xiong Puxian , Jiang Bofan , Zhou Shifeng , Ma Zhijun , Peng Mingying
Published: June 2021

The structure of the germanate glasses was depolymerized by introducing different types of alkaline earth metal fluorides from MgF2 to BaF2, which resulted in different luminescence behaviours of Bi-related NIR centers.
Optimization of brain-penetrant picolinamide derived leucine-rich repeat kinase 2 (LRRK2) inhibitors
Authors: Gulati Anmol , Yeung Charles S. , Lapointe Blair , Kattar Solomon D. , Gunaydin Hakan , Scott Jack D. , Childers Kaleen K. , Methot Joey L. , Simov Vladimir , Kurukulasuriya Ravi , Pio Barbara , Morriello Greg J. , Liu Ping , Tang Haiqun , Neelamkavil Santhosh , Wood Harold B. , Rada Vanessa L. , Ardolino Michael J. , Yan Xin Cindy , Palte Rachel , Otte Karin , Faltus Robert , Woodhouse Janice , Hegde Laxminarayan G. , Ciaccio Paul , Minnihan Ellen C. , DiMauro Erin F. , Fell Matthew J. , Fuller Peter H. , Ellis J. Michael
Published: June 2021

The evolution of picolinamide derived LRRK2 inhibitors with improved kinase off target selectivity and de-risked for AMES mutagenicity.
β-Adrenoceptor regulation of metabolism in U937 derived macrophages
Authors: Peterson Amanda L. , Siddiqui Ghizal , Sloan Erica K. , Creek Darren J.
Published: June 2021

Proteomics and metabolomics reveal a shifted metabolism to support elevated ROS and cytoskeletal protein changes in β-adrenergic stimulated macrophages.
3D-Assembled rutile TiO2spheres withc-channels for efficient lithium-ion storage
Authors: Hao Zhongkai , Tian Miao , Ren Yinjuan , Dai Wenrui , Wang Meng , Chen Wei , Xu Guo Qin
Published: June 2021

Benefiting from the synergistic effect of 3D architecture and the presence of c-Channels, flower-like rutile TiO2 spheres with radially organized subunit nanorods achieve the remarkable electrochemical performance and long-term cycling stability.
K2Pb(H2C3N3O3)4(H2O)4: a potential UV nonlinear optical material with large birefringence
Authors: Chen Yan , Hu Chunli , Fang Zhi , Mao Jianggao
Published: June 2021

K2Pb(H2C3N3O3)4(H2O)4 (I) features a 2D [K2PbO8(H2O)4]12- anionic layer and reveals a moderate SHG signal of approximately 2.6 × KDP.
Visible light induced deaminative alkylation of difluoroenoxysilanes: a transition metal free strategy
Authors: Huang Qi-Ping , Huang Yang , Wang An-Jun , Zhao Liang , Jia Jia , Yu Yanbo , Tong Jie , Gu Jiwei , He Chun-Yang
Published: June 2021

Visible-light-promoted deaminative alkylation of difluoroenoxysilanes utilizing Hantzsch ester as a catalyst or through substrate-induced pathway have been demonstrated.
[4 + 2] Cycloaddition of trifluoromethyl ketimines with 2-alkenyl azaarenes through selective C–F bond cleavage of CF3
Authors: Fu Yiwei , Qin Cong , Zhang Zhiqiang , Shi Haoyu , Zhao Jianbo , Gong Xueqing , Shi Lei , Li Hao
Published: June 2021

A transition-metal-free [4 + 2] cycloaddition of trifluoromethyl ketimines with 2-alkenyl azaarenes through selective C–F bond cleavage of CF3 has been developed to afford cis-tetrahydroxypyridine products in moderate yields under mild conditions.
Exploiting coordination geometry to tune the dimensions and processability of metallosupramolecular polymers
Authors: Bäumer Nils , Kartha Kalathil K. , Buss Stefan , Palakkal Jasnamol P. , Strassert Cristian A. , Fernández Gustavo
Published: June 2021

The increase in preorganization associated with coordination geometry changes is exploited to regulate solvation effects and, in turn, processability of metallosupramolecular polymers exhibiting close metal–metal contacts.
Mechanistic insights into the insertion and addition reactions of group 13 analogues of the six-membered N-heterocyclic carbenes: interplay of electrophilicity, basicity, and aromaticity governing the reactivity
Authors: Zhang Zheng-Feng , Su Ming-Der
Published: June 2021

On the basis of sophisticated theoretical models, the theoretical study demonstrated that the atomic radius of a group 13 element in a six-membered-ring NHC analogue plays an important role in determining its chemical reactivity.
A conductive polymer composed of a cellulose-based flexible film and carbon nanotubes
Authors: Yang Lechen , Wu Yan , Yang Feng , Wang Wenhao
Published: June 2021

A conductive polymer composed of cellulose-based flexible film and carbon nanotubes, which has good conductivity and flexibility, and shows good perception ability under a certain range of strain/stress or human activity conditions.
A color-tunable single-component luminescent molecule with multiple emission centers
Authors: Chen Junru , Chen Xiaojie , Liu Yanyan , Li Yang , Zhao Juan , Yang Zhiyong , Zhang Yi , Chi Zhenguo
Published: June 2021

Color tunable luminescent materials with multiple emission centers showing delayed fluorescence, single molecular phosphorescence and aggregated molecular phosphorescence are achieved, along with time-dependent and excitation-dependent properties.
Supramolecular packing of alkyl substituted Janus face all-cis 2,3,4,5,6-pentafluorocyclohexyl motifs
Authors: Clark Joshua L. , Taylor Alaric , Geddis Ailsa , Neyyappadath Rifahath M. , Piscelli Bruno A. , Yu Cihang , Cordes David B. , Slawin Alexandra M. Z. , Cormanich Rodrigo A. , Guldin Stefan , O'Hagan David
Published: June 2021

Theory and Langmuir isotherm analysis was used to explore the conformations and molecular packing of alkyl all-cis 2,3,4,5,6-pentafluorocyclohexyl motifs, which are prepared by direct aryl hydrogenations from alkyl- or vinyl-pentafluoroaryl benzenes.
Damming an electronic energy reservoir: ion-regulated electronic energy shuttling in a [2]rotaxane
Authors: Yu Shilin , Kupryakov Arkady , Lewis James E. M. , Martí-Centelles Vicente , Goldup Stephen M. , Pozzo Jean-Luc , Jonusauskas Gediminas , McClenaghan Nathan D.
Published: June 2021

Delayed emission due to reversible electronic energy transfer (REET) between chromophores in the axle and macrocycle components of a rotaxane is demonstrated. The REET process can be modulated by metal ion binding in the cavity of the rotaxane.
Sacrificial species approach to designing robust transition metal phosphide cathodes for alkaline water electrolysis in discontinuous operation
Authors: Kim Ik-Sun , Cho Hyun-Seok , Kim MinJoong , Oh Hyun-Jung , Lee Sang-Yeon , Lee Yong-Kul , Lee Changsoo , Lee Jae Hun , Cho Won Chul , Kim Sang-Kyung , Joo Jong Hoon , Kim Chang-Hee
Published: June 2021

The degradation of amorphous cobalt phosphides (CoPx) as an electrocatalyst for the hydrogen evolution reaction (HER) is studied in the discontinuous operation of alkaline water electrolysis cells (AWEs).
Interfacing RuO2with Pt to induce efficient charge transfer from Pt to RuO2for highly efficient and stable oxygen evolution in acidic media
Authors: Kwon Taehyun , Yang Heesu , Jun Minki , Kim Taekyung , Joo Jinwhan , Kim Jun , Baik Hionsuck , Kim Jin Young , Lee Kwangyeol
Published: June 2021

Efficient charge transfer fromin situformed PtOxto catalytically active RuO2in hetero-interfaced Au@Pt/RuO2nanowires effectively prevents the overoxidation of RuO2to soluble species during OER, leading to durable OER catalysis.
Deeply reconstructed hierarchical and defective NiOOH/FeOOH nanoboxes with accelerated kinetics for the oxygen evolution reaction
Authors: Yan Ping , Liu Qian , Zhang Hui , Qiu Luchun , Wu Hao Bin , Yu Xin-Yao
Published: June 2021

Hollow nanostructuring can facilitate the deep reconstruction of NiFeP into low-crystalline and defective heterostructured NiOOH/FeOOH with superior OER performance. In situ Raman spectroscopy shows evidence of the deep reconstruction process.
Electrospun regenerated Antheraea pernyi silk fibroin scaffolds with improved pore size, mechanical properties and cytocompatibility using mesh collectors
Authors: Zou Shengzhi , Wang Xinru , Fan Suna , Yao Xiang , Zhang Yaopeng , Shao Huili
Published: June 2021

An electrospun RASF scaffold was fabricated from its aqueous solution; the pore size, mechanical properties and cytocompatibility could be simultaneously improved by suitable mesh collectors.
A novel coating with universal adhesion and inflammation-responsive drug release functions to manipulate the osteoimmunomodulation of implants
Authors: He Min , Yang Bo , Huo Fangjun , Xie Li , Yang Mo , Tian Weidong
Published: June 2021

The immune response elicited by the bone endoprosthesis is currently considered an important factor that affects its interfacial osteointegration.
Selective detection of mercury ions based on tin oxide quantum dots: performance and fluorescence enhancement model
Authors: Liu Jianqiao , Bai Yu , Shi Jingcheng , Yu Qing , Liu Jifei , Yang Jiayu , Fu Ce , Zhang Qianru
Published: June 2021

The synthesized SnO2 QDs show excellent selective sensing performances in the detection of Hg2+ ions. An adsorption model is established for the mathematical description of fluorescence response of the SnO2 QDs sensor.
Blends of polymer semiconductor and polymer electrolyte for mixed ionic and electronic conductivity
Authors: Frankenstein Hadar , Stein Eyal , Stolov Mikhail , Koifman Khristosov Maria , Freger Viatcheslav , Frey Gitti L.
Published: June 2021

Mixed ionic and electronic conductivity is achieved by blending a semiconducting polymer, P3HT, with a polymer electrolyte, PEO. Blend composition and PEO Mw direct the blend morphology and tune the mixed conductivity.
Solution-processing of semiconducting organic small molecules: what we have learnt from 5,11-bis(triethylsilylethynyl)anthradithiophene
Authors: Yu Liyang , Portale Guiseppe , Stingelin Natalie
Published: June 2021

Processing strategies and methodologies are reviewed that allow the control and assessment of polymorph formation in semiconducting small molecules using 5,11-bis(triethylsilylethynyl) anthradithiophene (TES ADT) as a model material system.
Non-classical temperature-dependent phase sequence: long-lived metastable piezoelectric helical columnar liquid crystalline polymorph
Authors: Nguyen Manh Linh , Byun Jaeduk , Shin Tae Joo , Cho Byoung-Ki
Published: June 2021

Two individual polymorphs corresponding to piezoelectrically-active helical columnar LC and thermodynamically stable crystalline phases can be engineered at room temperature.
Serum CYR61 as a potential biomarker for the diagnosis of esophagogastric junction tumor
Authors: Chu Ling-Yu , Zhou Jian-Yuan , Zhao Yi-Xuan , Ou Yan-Ting , Yang Tian , Peng Yu-Hui , Fang Wang-Kai , Xu Yi-Wei , Xie Jian-Jun
Published: June 2021

Background: Esophagogastric junction tumor (EGJ) is a rare but fatal disease with a rapid rising incidence worldwide in the late 20 years, and it lacks a convenient and safe method for diagnosis. The present study aimed to evaluate the potential of serum CYR61 as a biomarker for the diagnosis of EGJ tumor.

Methods: Enzyme-linked immunosorbent assay (ELISA) was used to estimate CYR61 levels in sera of 152 EGJ tumor patients and 137 normal controls. Receiver operating characteristics (ROC) was carried out to evaluate the diagnostic accuracy. The Mann–Whitney’s U test was used to compare the difference of serum levels of CYR61 between groups. And chi-square tests were employed to estimate the correlation of the positive rate of serum CYR61 between/among subgroups.

Results: Serum CYR61 levels were statistically lower in EGJ tumor and early-stage EGJ tumor patients than those in normal controls (P<0.0001). The sensitivity, specificity and the area under the curve (AUC) of this biomarker in EGJ tumor were 88.2%, 43.8% and 0.691, respectively, and those for early stage of EGJ tumor were 80.0%, 66.4% and 0.722, respectively. Analyses showed that there was no correlation between the clinical data and the levels of CYR61 (P>0.05).

Conclusion: The present study showed that CYR61 might be a potential biomarker to assist the diagnosis of EGJ tumor.
Finite‐element calculation of electromagnetic characteristics and steady‐state stability of dual‐excited synchronous generator
Authors: Xu Guorui , Wang Zhenzhen , Liu Bingchen , Zhan Yang , Li Weili , Zhao Haisen , Huang Hao , Yu Honghao
Published: June 2021

The Dual‐Excited Synchronous Generator (DESG) has two sets of field windings. The magnitudes and directions of the two field currents can be regulated, so that the excitation magneto‐motive force can be in any direction. The electromagnetic characteristics of the DESG may be different with those of the Traditional Synchronous Generator (TSG) for the different rotor structures of the two generators. To obtain better electromagnetic characteristics, a time‐stepping finite element model (T‐S FEM) of the DESG is established. The air‐gap radial flux density, saturation, active and reactive power of the DESG in single‐ and dual‐axis excitation modes are calculated and compared with those of the TSG. The electromagnetic characteristics affected by the different ratio of q‐axis field current to d‐axis field current are studied. On this basis, an excitation control strategy that can enhance the steady‐state stability is proposed, and the steady‐state stability limits with and without excitation control are calculated by the T‐S FEM. A 10‐kW DESG is developed to verify the correctness of the simulation results. The results show that the DESG with dual‐axis excitation has better electromagnetic characteristics and stronger reactive power ability, and the steady‐state stability limit of the DESG is increased obviously through the excitation control.
Green synthesis of fly ash‐based zeolite Y by mixed alkali fusion method
Authors: Shi Bin , Chang Qing
Published: June 2021

A solvent‐free process was used to synthesize high‐purity zeolite Y from fly ash. Different from the traditional two‐step method, fly ash was activated efficiently by mixed alkali of NaOH and Na2CO3 at 750 °C for 2 h. For prepared zeolite Y, the composition, phase structure, morphology, specific surface areas and ammonium adsorption were evaluated comprehensively. The results show that a single phase zeolite Y with octahedral structure and an average diameter of 2.5 μm is obtained. The Brunauer–Emmett–Teller surface area is as high as 503.34 m2/g. Ammonium adsorption isotherm model on obtained zeolite Y was more consistent with the Langmuir model (R2 > 0.99). And the maximum adsorption capacity is 18.6 mg/g. It can be concluded that the study provides an economic process to utilize fly ash for the synthesis of zeolite Y, which is an excellent adsorbent to remove ammonium. In addition, this study provides an eco‐friendly approach to synthesize low‐cost zeolite Y from solid waste, which is of excellent adsorption for ammonium removal.
A simplified space vector modulation implementation for modular multilevel converter by grouping submodules
Authors: Bai Zhihong , Chen Haoqi , Li Yifei , Dong Yinuo , Ma Hao
Published: June 2021

Modulation strategy plays an important role in the good performance of modular multilevel converter (MMC). Since MMC has a special structure as well as a large number of submodules (SMs), it is almost impossible to apply the conventional multilevel space vector modulation (SVM) algorithm in it. In this study, a simplified SVM implementation method is proposed by grouping SMs. With the presented method, the high‐level SVM process for MMC can be easily done by implementing multiple two‐level or three‐level SVM algorithm, while the complicated offline or online efforts/tasks about mapping switching states or sequences in the conventional multilevel SVM are not necessary any more. In order to improve the harmonic characteristics, the sampling time of different subunits (SUs), each of which is formed by grouping a few SMs, is staggered evenly, which helps to achieve a higher equivalent switching frequency and less low‐order harmonics. Further, the capacitor voltage balance of SMs is improved by rotation strategies between SUs or inside each SU even without any capacitor voltage detecting or sorting. Since the presented method is independent of the number of SMs, it can be very easily expanded into a high‐level MMC. These propositions are verified by experiment.
Radar target classification considering unknown classes using deep convolutional neural network ensemble
Authors: Lee Byeong–ho , Lee Seongwook , Kang Seokhyun , Kim Seong–Cheol , Kim Yong–Hwa
Published: June 2021

The target classification of unknown classes using radar sensor data is discussed. The neural network‐based classifier shows high classification accuracy for the learned class targets. However, there is a risk of false decision for the untrained class target owing to an overconfidence problem. The output confidence of the classifier is calibrated using the deep convolutional neural network ensemble structure to propose a method to set the proper threshold for output confidence to decide unknown class targets. When using the proposed method, the accuracy of the learned target is maintained similar to that of the existing single neural network‐based classifier, whereas the unknown class target is better identified. Further analysis verifies the effectiveness of the proposed method using commercial automotive radar. The proposed method can classify learned targets with an accuracy of 95% and distinguish unknown class targets with an accuracy of at least 85%. Based on the interaction with other sensors, individual sensors need to make reserved decisions about uncertain information. It is expected that the proposed ensemble network will be efficient in designing the classifier to perform target classification including unknown class decision.
Interior heating and outgassing of Proxima Centauri b: Identifying critical parameters
Authors: Noack L. , Kislyakova K. G. , Johnstone C. P. , Güdel M. , Fossati L.
Published: June 2021

Context. Since the discovery of a potentially low-mass exoplanet around our nearest neighbour star Proxima Centauri, several works have investigated the likelihood of a shielding atmosphere and therefore the potential surface habitability of Proxima Cen b. However, outgassing processes are influenced by several different (unknown) factors such as the actual planet mass, mantle and core composition, and different heating mechanisms in the interior.

Aims. We aim to identify the critical parameters that influence the mantle and surface evolution of the planet over time, as well as to potentially constrain the time-dependent input of volatiles from mantle into the atmosphere.

Methods. To study the coupled star–planet evolution, we analysed the heating produced in the interior of Proxima Cen b due to induction heating, which strongly varies with both depth and latitude. We calculated different rotation evolutionary tracks for Proxima Centauri and investigated the change in its rotation period and magnetic field strength. Unlike the Sun, Proxima Centauri possesses a very strong magnetic field of at least a few hundred Gauss, which was likely even stronger in the past. We applied an interior structure model for varying planet masses (derived from the unknown inclination of observation of the Proxima Centauri system) and iron weight fractions, that is, different core sizes, in the range of observed Fe-Mg variations in the stellar spectrum. We used a mantle convection model to study the thermal evolution and outgassing efficiency of Proxima Cen b. For unknown planetary parameters such as initial conditions, we chose randomly selected values. We took heating in the interior due to variable radioactive heat sources and induction heating into account and compared the heating efficiency to tidal heating.

Results. Our results show that induction heating may have been significant in the past, leading to local temperature increases of several hundreds of Kelvin. This early heating leads to an earlier depletion of the interior and volatile outgassing compared to if the planet had not been subject to induction heating. We show that induction heating has an impact comparable to tidal heating when assuming latest estimates on its eccentricity. Furthermore, we find that the planet mass (linked to the planetary orbital inclination) has a first-order influence on the efficiency of outgassing from the interior.
Cumulene carbenes in TMC-1: Astronomical discovery of l-H2C5
Authors: Cabezas C. , Tercero B. , Agúndez M. , Marcelino N. , Pardo J. R. , de Vicente P. , Cernicharo J.
Published: June 2021

We report the first detection in space of the cumulene carbon chain l-H2C5. A total of eleven rotational transitions, with Jup = 7−10 and Ka = 0 and 1, were detected in TMC-1 in the 31.0–50.4 GHz range using the Yebes 40 m radio telescope. We derived a column density of (1.8 ± 0.5)×1010 cm−2. In addition, we report observations of other cumulene carbenes detected previously in TMC-1 in order to compare their abundances with the newly detected cumulene carbene chain. We find that l-H2C5 is ∼4.0 times less abundant than the larger cumulene carbene l-H2C6, while it is ∼300 and ∼500 times less abundant than the shorter chains l-H2C3 and l-H2C4. We discuss the most likely gas-phase chemical routes to these cumulenes in TMC-1 and stress that chemical kinetics studies able to distinguish between different isomers are needed to shed light on the chemistry of CnH2 isomers with n > 3.
Approximation of null controls for semilinear heat equations using a least-squares approach
Authors: Lemoine Jérôme , Marín-Gayte Irene , Münch Arnaud
Published: June 2021

The null distributed controllability of the semilinear heat equation∂ty− Δy+g(y) =f1ωassuming thatg∈C1(ℝ) satisfies the growth condition lim sup|r|→∞g(r)∕(|r|ln3∕2|r|) = 0 has been obtained by Fernández-Cara and Zuazua (2000). The proof based on a non constructive fixed point theorem makes use of precise estimates of the observability constant for a linearized heat equation. Assuming thatg′ is bounded and uniformly Hölder continuous on ℝ with exponentp∈ (0, 1], we design a constructive proof yielding an explicit sequence converging strongly to a controlled solution for the semilinear equation, at least with order 1 +pafter a finite number of iterations. The method is based on a least-squares approach and coincides with a globally convergent damped Newton method: it guarantees the convergence whatever be the initial element of the sequence. Numerical experiments in the one dimensional setting illustrate our analysis.
Use of the water-swellable polymers (WSP) for wellbore stabilization in intensely fractured rock intervals
Authors: Sadykov M.I. , Blinov P.A. , Nutskova M.V.
Published: June 2021

Current research on the stability of well walls when drilling in fractured rocks and also when drilling inclined sections of the well profile are based on the assessment of the effect of drilling fluid filtrate. The novelty of this work lies in studying the complex effect of a water-swellable polymer on the stability of well wall, on the one hand, and on the controlled loss of circulation on the other. For preparing rock samples, a method was used based on standard laboratory equipment fordrilling fluid properties. The well wall stability tests are performedon a direct shear apparatus.The WSP composition based on alcohol, ether, and surfactant (Polyecanol Flora) showed its efficiency by increasing the stability coefficient with the engagement of less and more internal friction angle.PHPA-based viscoelastic composition showed the best result by increasing the stability coefficient in the hazardous areas by 50-60%.
Static model of oil viscosity reduction for automatic pulse current exposure regulation system
Authors: Sasarov V. A. , Yudin A. V. , Fedorova M. A.
Published: June 2021

The article considers an open automatic control system (ACS) with compensation based on a model of the viscosity reduction process. The model is implemented in the MATLAB system and takes into account the initial kinematic viscosity of the oil, its temperature, and density. Modeling of each block of the proposed ACS is performed. An example of the functioning of the ACS to compensate for temperature effect is considered.
A brief comparative study of the potentialities and limitations of machine-learning algorithms and statistical techniques
Authors: Eckart Li , Eckart Sven , Enke Margit
Published: June 2021

Machine learning is a popular way to find patterns and relationships in high complex datasets. With the nowadays advancements in storage and computational capabilities, some machine-learning techniques are becoming suitable for real-world applications. The aim of this work is to conduct a comparative analysis of machine learning algorithms and conventional statistical techniques. These methods have long been used for clustering large amounts of data and extracting knowledge in a wide variety of science fields. However, the central knowledge of the different methods and their specific requirements for the data set, as well as the limitations of the individual methods, are an obstacle for the correct use of these methods. New machine learning algorithms could be integrated even more strongly into the current evaluation if the right choice of methods were easier to make. In the present work, some different algorithms of machine learning are listed. Four methods (artificial neural network, regression method, self-organizing map, k-means al-algorithm) are compared in detail and possible selection criteria are pointed out. Finally, an estimation of the fields of work and application and possible limitations are provided, which should help to make choices for specific interdisciplinary analyses.
Increasing the depth of apatite processing by extracting rare-earth elements
Authors: Lukyantseva E.S. , Sergeev V.V.
Published: June 2021

Currently, most high-technology productions are impossible without rare-earth elements (REE). The heavy rare-earth elements are of great interest as they have the highest market value and are in demand in the vast majority of knowledge-intensive industries. The main recourse of REE in Russia is apatite ore which is used in the production of fertilizers. As a result of its leaching, about 15-20% of REE goes to wet-process phosphoric acid. To enhance the depth of apatite processing, it is necessary to develop a technology which will allow obtaining rare-earth elements as by-products. The method of extraction and concentration of REE discussed in this paper was conducted by using the extractant based on di-(2-ethylhexyl) phosphoric acid (D2EHPA). The mechanism of extraction was studied, as well as the impact of the extractant concentration, phase ratio and the number of stages on the extraction process.