bluuebunny/crossref_metadata_2025 huggingface dataset:
Polycrystalline SnSe with a thermoelectric figure of merit greater than the single crystal
Authors: Zhou Chongjian , Lee Yong Kyu , Yu Yuan , Byun Sejin , Luo Zhong-Zhen , Lee Hyungseok , Ge Bangzhi , Lee Yea-Lee , Chen Xinqi , Lee Ji Yeong , Cojocaru-Mirédin Oana , Chang Hyunju , Im Jino , Cho Sung-Pyo , Wuttig Matthias , Dravid Vinayak P. , Kanatzidis Mercouri G. , Chung In
Published: August 2021

Thermoelectric materials generate electric energy from waste heat, with conversion efficiency governed by the dimensionless figure of merit, ZT. Single-crystal tin selenide (SnSe) was discovered to exhibit a high ZT of roughly 2.2–2.6 at 913 K, but more practical and deployable polycrystal versions of the same compound suffer from much poorer overall ZT, thereby thwarting prospects for cost-effective lead-free thermoelectrics. The poor polycrystal bulk performance is attributed to traces of tin oxides covering the surface of SnSe powders, which increases thermal conductivity, reduces electrical conductivity and thereby reduces ZT. Here, we report that hole-doped SnSe polycrystalline samples with reagents carefully purified and tin oxides removed exhibit an ZT of roughly 3.1 at 783 K. Its lattice thermal conductivity is ultralow at roughly 0.07 W m–1 K–1 at 783 K, lower than the single crystals. The path to ultrahigh thermoelectric performance in polycrystalline samples is the proper removal of the deleterious thermally conductive oxides from the surface of SnSe grains. These results could open an era of high-performance practical thermoelectrics from this high-performance material.
The Upworthy Research Archive, a time series of 32,487 experiments in U.S. media
Authors: Matias J. Nathan , Munger Kevin , Le Quere Marianne Aubin , Ebersole Charles
Published: August 2021

The pursuit of audience attention online has led organizations to conduct thousands of behavioral experiments each year in media, politics, activism, and digital technology. One pioneer of A/B tests was Upworthy.com, a U.S. media publisher that conducted a randomized trial for every article they published. Each experiment tested variations in a headline and image “package,” recording how many randomly-assigned viewers selected each variation. While none of these tests were designed to answer scientific questions, scientists can advance knowledge by meta-analyzing and data-mining the tens of thousands of experiments Upworthy conducted. This archive records the stimuli and outcome for every A/B test fielded by Upworthy between January 24, 2013 and April 30, 2015. In total, the archive includes 32,487 experiments, 150,817 experiment arms, and 538,272,878 participant assignments. The open access dataset is organized to support exploratory and confirmatory research, as well as meta-scientific research on ways that scientists make use of the archive.
Optimal solution of the fractional order breast cancer competition model
Authors: Hassani H. , Machado J. A. Tenreiro , Avazzadeh Z. , Safari E. , Mehrabi S.
Published: August 2021

In this article, a fractional order breast cancer competition model (F-BCCM) under the Caputo fractional derivative is analyzed. A new set of basis functions, namely the generalized shifted Legendre polynomials, is proposed to deal with the solutions of F-BCCM. The F-BCCM describes the dynamics involving a variety of cancer factors, such as the stem, tumor and healthy cells, as well as the effects of excess estrogen and the body’s natural immune response on the cell populations. After combining the operational matrices with the Lagrange multipliers technique we obtain an optimization method for solving the F-BCCM whose convergence is investigated. Several examples show that a few number of basis functions lead to the satisfactory results. In fact, numerical experiments not only confirm the accuracy but also the practicability and computational efficiency of the devised technique.
Distinct mutations in importin-β family nucleocytoplasmic transport receptors transportin-SR and importin-13 affect specific cargo binding
Authors: Kimura Makoto , Imai Kenichiro , Morinaka Yuriko , Hosono-Sakuma Yoshiko , Horton Paul , Imamoto Naoko
Published: August 2021

Importin-(Imp)β family nucleocytoplasmic transport receptors (NTRs) are supposed to bind to their cargoes through interaction between a confined interface on an NTR and a nuclear localization or export signal (NLS/NES) on a cargo. Although consensus NLS/NES sequence motifs have been defined for cargoes of some NTRs, many experimentally identified cargoes of those NTRs lack those motifs, and consensus NLSs/NESs have been reported for only a few NTRs. Crystal structures of NTR–cargo complexes have exemplified 3D structure-dependent binding of cargoes lacking a consensus NLS/NES to different sites on an NTR. Since only a limited number of NTR–cargo interactions have been studied, whether most cargoes lacking a consensus NLS/NES bind to the same confined interface or to various sites on an NTR is still unclear. Addressing this issue, we generated four mutants of transportin-(Trn)SR, of which many cargoes lack a consensus NLS, and eight mutants of Imp13, where no consensus NLS has been defined, and we analyzed their binding to as many as 40 cargo candidates that we previously identified by a nuclear import reaction-based method. The cargoes bind differently to the NTR mutants, suggesting that positions on an NTR contribute differently to the binding of respective cargoes.
Decreased risk of liver and intrahepatic cancer in non-H. pylori-infected perforated peptic ulcer patients with truncal vagotomy: a nationwide study
Authors: Wu Shih-Chi , Cheng Han-Tsung , Wang Yu-Chun , Tzeng Chia-Wei , Hsu Chia-Hao , Muo Chih-Hsin
Published: August 2021

The vagal nervous system is central to the physiological responses and systemic diseases of the liver. We evaluated the subsequent risk of liver and intrahepatic cancer (HCC/ICC) in non-H. pylori (HP)-infected perforated peptic ulcer (PPU) patients with and without vagotomy. Hospitalized PPU patients who underwent simple closure or truncal vagotomy/pyloroplasty (TVP) in the National Health Insurance Research Database from 2000 to 2008 were enrolled. The exclusion criteria included: (1) Multiple surgeries for PPU were received at the same admission; (2) Any cancer history; (3) Previous peptic ulcer-associated surgery; (4) HP infection history; (5) Viral hepatitis infection history; (6) Follow-up duration < 1 year; and (7) Age < 18 years. The risks of developing HCC/ICC in PPU patients with and without vagotomy were assessed at the end of 2013. To balance the baseline condition between groups, we used the propensity score matched method to select study subjects. Cox proportional hazard regression was used to estimate the hazard ratio and 95% confidence interval (CI) of HCC/ICC. Before propensity score matching, 675 simple suture patients and 54 TVP patients had HCC/ICC, which corresponded to incidences of 2.11 and 0.88 per 1000 person-years, respectively. After propensity score matching, 145 simple suture patients and 54 TVP patients experienced HCC/ICC, which corresponded to incidences of 1.45 and 0.88 per 1000 person-years, respectively. The TVP patients had a 0.71 (95% CI 0.54–0.95)- and 0.69 (95% CI 0.49–0.97)-fold risk of developing HCC/ICC compared to simple suture patients before and after propensity score matching. Our findings reported that, in the Asian population, TVP decreases the risk of HCC/ICC in non-HP-infected PPU patients compared to simple closure patients. However, further studies are warranted.
The clinical utility of a comprehensive psychosomatic assessment in the program for colorectal cancer prevention: a cross-sectional study
Authors: Gostoli Sara , Montecchiarini Maria , Urgese Alessia , Ferrara Francesco , Polifemo Anna Maria , Ceroni Liza , Gasparri Asia , Rafanelli Chiara , Cennamo Vincenzo
Published: August 2021

Few studies have investigated psychosocial characteristics and lifestyle behaviors of participants at programs for secondary prevention of colorectal cancer (CRC). This study aimed, through a comprehensive psychosomatic assessment based on clinimetric principles, to evaluate psychosocial characteristics and lifestyle behaviors in participants at CRC secondary prevention program, and to investigate the associations between these variables and endoscopic outcomes. In this cross-sectional study, the first 150 consecutive asymptomatic participants at the CRC prevention program who resulted positive to fecal occult blood test (FOBT) and were thus referred to colonoscopy, underwent a psychosomatic assessment including psychiatric diagnoses (DSM-5), psychosomatic syndromes (DCPR-R), psychological distress, psychological well-being and lifestyle behaviors. Whereas only 5.3% of the sample showed at least one DSM-5 diagnosis, 51.3% showed at least one DCPR syndrome, such as allostatic overload, alexithymia, Type A behavior, and demoralization. Patients affected by psychosomatic syndromes presented with significantly higher psychological distress, lower psychological well-being and unhealthy lifestyle behaviors, such as tobacco smoking and unhealthy diet, in comparison with patients without DCPR syndromes. Among endoscopic outcomes, the presence of adenomas was significantly associated with DCPR irritable mood. In a clinical context of secondary prevention addressing asymptomatic patients with positive FOBT, a comprehensive psychosomatic assessment may provide relevant clinical information for those patients who present certain psychosomatic syndromes associated with high psychological distress, impaired psychological well-being, unhealthy lifestyle behaviors and colorectal precancerous lesions. The results of the present study indicate a road to the practice of “preventive” medicine at CRC screening program.
OCTA reveals remodeling of the peripheral capillary free zones in normal aging
Authors: Arthur Edmund , Alber Jessica , Thompson Louisa I. , Sinoff Stuart , Snyder Peter J.
Published: August 2021

The retinal neurovascular unit consists of blood vessel endothelial cells, pericytes, neurons, astrocytes, and Müller cells that form the inner retinal blood barrier. A peripheral capillary free zone (pCFZ) represents the distance that oxygen and nutrients must diffuse to reach the neural retina, and serves as a metric of retinal tissue oxygenation. The pCFZs are formed based on oxygen saturation in the retinal arterioles and venules. Because retinal arterioles contain a larger concentration of oxygenated blood than venules, there is a reduced need for capillaries to exist closely to arterioles compared to venules. Therefore, in a healthy individual, larger periarteriole CFZs are expected compared to perivenule CFZs. With normal aging, there is atrophy of the inner retinal neurons, and consequently reduced extraction of oxygen and nutrients from the retinal vessels (i.e., increased oxygen saturation). Therefore, we hypothesized that the peripheral CFZ will remodel with normal aging. Using Optical Coherence Tomography Angiography, we showed that the pCFZs do remodel in normal aging with large (perivenule: η2p = 0.56) and moderate (periarteriole: η2p = 0.12) effect sizes, opening the possibility that such changes may be further increased by neurodegenerative diseases that adversely impact the health of the retinal neural cell layers.
Personalised therapeutic management of epileptic patients guided by pathway-driven breath metabolomics
Authors: Singh Kapil Dev , Osswald Martin , Ziesenitz Victoria C. , Awchi Mo , Usemann Jakob , Imbach Lukas L. , Kohler Malcolm , García-Gómez Diego , van den Anker Johannes , Frey Urs , Datta Alexandre N. , Sinues Pablo
Published: August 2021

Background

Therapeutic management of epilepsy remains a challenge, since optimal systemic antiseizure medication (ASM) concentrations do not always correlate with improved clinical outcome and minimal side effects. We tested the feasibility of noninvasive real-time breath metabolomics as an extension of traditional therapeutic drug monitoring for patient stratification by simultaneously monitoring drug-related and drug-modulated metabolites.

Methods

This proof-of-principle observational study involved 93 breath measurements of 54 paediatric patients monitored over a period of 2.5 years, along with an adult’s cohort of 37 patients measured in two different hospitals. Exhaled breath metabolome of epileptic patients was measured in real time using secondary electrospray ionisation–high-resolution mass spectrometry (SESI–HRMS).

Results

We show that systemic ASM concentrations could be predicted by the breath test. Total and free valproic acid (VPA, an ASM) is predicted with concordance correlation coefficient (CCC) of 0.63 and 0.66, respectively. We also find (i) high between- and within-subject heterogeneity in VPA metabolism; (ii) several amino acid metabolic pathways are significantly enriched (p < 0.01) in patients suffering from side effects; (iii) tyrosine metabolism is significantly enriched (p < 0.001), with downregulated pathway compounds in non-responders.

Conclusions

These results show that real-time breath analysis of epileptic patients provides reliable estimations of systemic drug concentrations along with risk estimates for drug response and side effects.
Hyperspectral-enhanced dark field analysis of individual and collective photo-responsive gold–copper sulfide nanoparticles
Authors: Zamora-Perez Paula , Pelaz Beatriz , Tsoutsi Dionysia , Soliman Mahmoud G. , Parak Wolfgang J. , Rivera-Gil Pilar
Published: August 2021

Hyperspectral-enhanced dark field microscopy to correlate Au/CuS NPs’ changes in their physicochemical properties induced by cellular environments with their functionality as photothermal probes by tracking their scattering profile evolution in real time.
An artificial enzyme cascade amplification strategy for highly sensitive and specific detection of breast cancer-derived exosomes
Authors: Xu Huiying , Zheng Lu , Zhou Yu , Ye Bang-Ce
Published: August 2021

An artificial enzyme cascade amplification strategy based on a switchable DNA tetrahedral scaffold was proposed for high sensitivity analysis of exosomes.
Cerium oxide modified iridium nanorods for highly efficient electrochemical water splitting
Authors: Xu Kai , Zhu Zizheng , Guo Wen , Zhang Hongyan , Yu Tingting , Wei Wenxian , Liang Wenjie , Zhang Dongen , He Maoshuai , Yang Tao
Published: August 2021

Ir catalytic activities towards electrochemical oxygen evolution and hydrogen generation were greatly enhanced by Ce incorporation through interfacial electron synergism.
Unveiling anion-induced folding in tripodal imidazolium receptors by ion-mobility mass spectrometry
Authors: Vicent Cristian , Valls Adriana , Escorihuela Jorge , Altava Belén , Luis Santiago
Published: August 2021

The anion-induced folding of tripodal imidazolium receptors is unveiled by Ion mobility mass spectrometry and DFT calculations.
Electrochemical reduction of fluoroalkyl sulfones for radical fluoroalkylation of alkenes
Authors: Zhou Xin , Ni Chuanfa , Deng Ling , Hu Jinbo
Published: August 2021

Radical fluoroalkylation of alkenes has been developed by electrochemical reduction of fluoroalkyl sulfones.
3d–4f Heterometallic cluster incorporated polyoxoniobates with magnetic properties
Authors: Lin Yu-Diao , Ge Rui , Tian Chong-Bin , Sun Cai , Sun Yan-Qiong , Zeng Qing-Xin , Li Xin-Xiong , Zheng Shou-Tian
Published: August 2021

A series of 3d–4f heterometallic cluster incorporated polyoxoniobates (PONbs) were first made and characterized, demonstrating an ideal model to probe how transition-metal ions influence the magnetic properties of PONbs.
Quasi single-crystalline transformation of porous frameworks accompanied by interlayer rearrangements of hydrogen bonds
Authors: Kubo Haruka , Oketani Ryusei , Hisaki Ichiro
Published: August 2021

Quasi single-crystal-to-single-crystal transformation of a hydrogen-bonded organic framework (HOF) was accurately revealed and the mechanism was proposed.
Cu-based metal–organic frameworks for highly sensitive X-ray detectors
Authors: Li Zheng , Chang Shuquan , Zhang Haiqian , Hu Yong , Huang Yulong , An Lu , Ren Shenqiang
Published: August 2021

A high-performance Cu-DABDT-based X-ray detector was fabricated where Cu-DABDT was synthesized by conjugating copper cations and DABDT ligands.
DABCO catalyzed [4+2] annulations of Morita–Baylis–Hillman carbonates with isocyanates
Authors: Cai Wei , Zhou Yiming , He Yanlin , Huang You
Published: August 2021

A series of o-amino-acylation aryl MBH carbonates are designed to be used as 1,4-dipoles to participate in annulation reactions.
Anchoring of a hydrophobic heptapeptide (AFILPTG) on silica facilitates peptide unfolding at the abiotic–biotic interface
Authors: Volkov Victor V. , Heinz Hendrik , Perry Carole C.
Published: August 2021

We describe the interaction of a hydrophobic peptide with silica. Fitting of structures identified by simulation and use of natural transition orbitals to interpret CD data show that anchoring involves functional side groups, water and metal ions.
Sulfonate improves water solubility and cell selective toxicity and alters the lysozyme binding activity of half sandwich Rh(iii) complexes
Authors: Mansour Ahmed M. , Radacki Krzysztof , Shehab Ola R.
Published: August 2021

Introduction of the propyl-sulfonic acid group at N1 of the coordinated 2(pyridyl)benzimidazole ligand (L) in [RhCl(η5-C5Me5)L](CF3SO3) gives rise to a water-soluble complex, which shows comparable antifungal activity to Fluconazole.
Correction: Dinuclear cobalt complexes with a redox active biphenyl bridging ligand [Co2(BP)(tqa)2](PF6)2 (H4BP = 4,4′-bis(3-tert-butyl-1,2-catechol), tqa = tris(2-quinolylmethyl)amine): structure and magnetic properties
Authors: Suenaga Yusaku , Mibu Takuto , Okubo Takashi , Maekawa Masahiko , Kuroda-Sowa Takayoshi , Sugimoto Kunihisa
Published: August 2021

Correction for ‘Dinuclear cobalt complexes with a redox active biphenyl bridging ligand [Co2(BP)(tqa)2](PF6)2 (H4BP = 4,4′-bis(3-tert-butyl-1,2-catechol), tqa = tris(2-quinolylmethyl)amine): structure and magnetic properties’ by Yusaku Suenaga et al., Dalton Trans., 2021, DOI: 10.1039/d1dt00995h.
Sodium caprylate improves intestinal mucosal barrier function and antioxidant capacity by altering gut microbial metabolism
Authors: Zhao Jinbiao , Hu Jinhua , Ma Xi
Published: August 2021

Short-chain fatty acids (SCFA) produced by gut microbial metabolism have been reported to regulate the immunological response and intestinal health of the host by activating G protein-coupled receptors (GPR).
The fragmentation mechanism of gold nanoparticles in water under femtosecond laser irradiation
Authors: Bongiovanni Gabriele , Olshin Pavel K. , Yan Chengcheng , Voss Jonathan M. , Drabbels Marcel , Lorenz Ulrich J.
Published: August 2021

Direct observation of Coulomb fission of plasmonic nanoparticles in water.
Simple preparation of a durable and low-cost load-bearing three-dimensional porous material for emulsion separation
Authors: Fan Mingzhi , Ren Zhiying , Zhang Zhen , Yang Yu , Guo Zhiguang
Published: August 2021

Superhydrophobic MR–C composites were used for the separation of water-in-oil emulsions. Under a load of 500 N with a reciprocating wear, the contact angle was kept at 146 ± 2°. The oil-in-water emulsion can still be separated efficiently.
Squaramide-catalysed asymmetric Michael addition/cyclization cascade reaction of 4-arylmethylidene-2,3-dioxopyrrolidines with 2-isothiocyanato-1-indanones
Authors: Hou Xi-Qiang , Wen Jiang-Bo , Yan Li , Du Da-Ming
Published: August 2021

An efficient squaramide-catalysed asymmetric Michael/cyclization cascade reaction of 4-arylidene-2,3-dioxopyrrolidines with 2-isothiocyanato-1-indanones afforded indanone-derived spiropyrrolidones in excellent yields with high stereoselectivities.
Introduction to Luminogenic bioprobes for personal health technologies
Authors: Tang Youhong , Ding Dan
Published: August 2021

Youhong Tang and Dan Ding introduce the Materials Chemistry Frontiers themed collection on luminogenic bioprobes for personal health technologies.
Silver-catalyzed desulfurizative annulation of 1,2-benzisothiazoles with ynamides to construct multi-substituted isoquinolines
Authors: Fu Rui , Liu Ran , Lv Kang , Zhu Changlei , Bao Xiaoguang
Published: August 2021

An unprecedented silver-catalyzed desulfurizative annulation of 1,2-benzisothiazoles with ynamides to access multi-substituted isoquinoline derivatives is disclosed.
Turning waste into wealth: facile and green synthesis of carbon nanodots from pollutants and applications to bioimaging
Authors: Chen Weifeng , Shen Jialu , Wang Zuo , Liu Xiang , Xu Yanyi , Zhao Haiyu , Astruc Didier
Published: August 2021

The pollutant reactive red 2 was employed to synthesize fluorescent carbon nanodots allowing biological imaging in vitro and in vivo.
MgCo2O4-based electrode materials for electrochemical energy storage and conversion: a comprehensive review
Authors: Wu Runze , Sun Jiale , Xu Chunju , Chen Huiyu
Published: August 2021

In this review, recent advancement on the MgCo2O4-based electrode materials for supercapacitors, Li-ion battery, Mg-ion battery, and some other rechargeable ion batteries is discussed in details.
Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
Authors: Graś Małgorzata , Kolanowski Łukasz , Chen Zhijie , Lota Katarzyna , Jurak Kacper , Ryl Jacek , Ni Bing-Jie , Lota Grzegorz
Published: August 2021

Utilization of activated carbons from coffee waste in the complex borohydride electrooxidation process has great potential in increasing the efficiency of an anode based on the AB5-hydrogen storage alloy, as well as in proper management of waste.
Linear triglycerol-based fluorosurfactants show high potential for droplet-microfluidics-based biochemical assays
Authors: Chowdhury Mohammad Suman , Zheng Wenshan , Singh Abhishek Kumar , Ong Irvine Lian Hao , Hou Yong , Heyman John A. , Faghani Abbas , Amstad Esther , Weitz David A. , Haag Rainer
Published: August 2021

We decoupled the influence of different spatial geometries of oligoglycerol-based head groups and contributed to the goal of rational fluorosurfactant design for droplet microfluidics-based water-in-oil emulsions and suited applications.
Perfluorinated ionomer and poly(3,4-ethylenedioxythiophene) colloid as a hole transporting layer for optoelectronic devices
Authors: Li Wei-Long , Hou Cheng-Hung , Yang Chi-Ming , Tsai Kuen-Wei , Wu Jhao-Lin , Hsiao Yu-Tang , Hanmandlu Chintam , Chu Chih-Wei , Tsai Chia-Hua , Liao Chuang-Yi , Shyue Jing-Jong , Chang Yi-Ming
Published: August 2021

A polymer-based hole-transporting layer (HTL) with a tunable work function and highest occupied molecular orbital (HOMO) position was demonstrated to effectively optimize the anode junctions of optoelectronic devices.
Field emission applications of graphene-analogous two-dimensional materials: recent developments and future perspectives
Authors: Patra Abhinandan , More Mahendra A. , Late Dattatray J. , Rout Chandra Sekhar
Published: August 2021

This review provides the basic working principles of field emission, the advantages of 2D materials and various approaches to further tune the performance for cold field emitter devices.
High-efficiency red perovskite light-emitting diodes based on collaborative optimization of emission layer and transport layers
Authors: Shi Hongfei , Wang Zhibin , Ma Huanyu , Jia Haoran , Wang Fuzhi , Zou Cao , Hu Siqian , Li Hui , Tan Zhan’ao
Published: August 2021

Collaborative optimization of emission layer and transport layers is employed to minimize the energy loss at the interface of all-solution-processed metal halide perovskite light-emitting diodes.
Conductive thermoplastic polyurethane nanocomposite foams derived from a cellulose/MWCNTs aerogel framework: simultaneous enhancement of piezoresistance, strength, and endurance
Authors: Fei Yanpei , Chen Feng , Fang Wei , Hejna Aleksander , Xu Lixin , Liu Tong , Zhong Mingqiang , Yang Jintao , Kuang Tairong
Published: August 2021

Cellulose/MWCNTs/TPU nanocomposite foams were successfully fabricated via a freeze-drying technique and ScCO2 foaming. The microcellular structure of the composite foams showed potential application for polymer composite foams in wearable sensor devices.
Engineering potassium activation into biosynthetic thiolase
Authors: Marshall Andrew C. , Bruning John B.
Published: August 2021

Activation of enzymes by monovalent cations (M+) is a widespread phenomenon in biology. Despite this, there are few structure-based studies describing the underlying molecular details. Thiolases are a ubiquitous and highly conserved family of enzymes containing both K+-activated and K+-independent members. Guided by structures of naturally occurring K+-activated thiolases, we have used a structure-based approach to engineer K+-activation into a K+-independent thiolase. To our knowledge, this is the first demonstration of engineering K+-activation into an enzyme, showing the malleability of proteins to accommodate M+ ions as allosteric regulators. We show that a few protein structural features encode K+-activation in this class of enzyme. Specifically, two residues near the substrate-binding site are sufficient for K+-activation: A tyrosine residue is required to complete the K+ coordination sphere, and a glutamate residue provides a compensating charge for the bound K+ ion. Further to these, a distal residue is important for positioning a K+-coordinating water molecule that forms a direct hydrogen bond to the substrate. The stability of a cation–π interaction between a positively charged residue and the substrate is determined by the conformation of the loop surrounding the substrate-binding site. Our results suggest that this cation–π interaction effectively overrides K+-activation, and is, therefore, destabilised in K+-activated thiolases. Evolutionary conservation of these amino acids provides a promising signature sequence for predicting K+-activation in thiolases. Together, our structural, biochemical and bioinformatic work provide important mechanistic insights into how enzymes can be allosterically activated by M+ ions.
miR-219-5p targets TBXT and inhibits breast cancer cell EMT and cell migration and invasion
Authors: Ye Qin , Wang Xing , Yuan Mei , Cui Shuaishuai , Chen Yuanyuan , Hu Zhaodi , Liu Dandan , Han Conghui , Li Bibo , Chen Dahu
Published: August 2021

miR-219-5p has been reported to act as either a tumor suppressor or a tumor promoter in different cancers by targeting different genes. In the present study, we demonstrated that miR-219-5p negatively regulated the expression of TBXT, a known epithelial–mesenchymal transition (EMT) inducer, by directly binding to TBXT 3′-untranslated region. As a result of its inhibition on TBXT expression, miR-219-5p suppressed EMT and cell migration and invasion in breast cancer cells. The re-introduction of TBXT in miR-219-5p overexpressing cells decreased the inhibitory effects of miR-219 on EMT and cell migration and invasion. Moreover, miR-219-5p decreased breast cancer stem cell (CSC) marker genes expression and reduced the mammosphere forming capability of cells. Overall, our study highlighted that TBXT is a novel target of miR-219-5p. By suppressing TBXT, miR-219-5p plays an important role in EMT and cell migration and invasion of breast cancer cells.
Butyryl/Caproyl-CoA:Acetate CoA-transferase: cloning, expression and characterization of the key enzyme involved in medium-chain fatty acid biosynthesis
Authors: Yang Qingzhuoma , Guo Shengtao , Lu Qi , Tao Yong , Zheng Decong , Zhou Qinmao , Liu Jun
Published: August 2021

Coenzyme A transferases (CoATs) are important enzymes involved in carbon chain elongation, contributing to medium-chain fatty acid (MCFA) biosynthesis. For example, butyryl-CoA:acetate CoA transferase (BCoAT) is responsible for the final step of butyrate synthesis from butyryl-CoA. However, little is known about caproyl-CoA:acetate CoA-transferase (CCoAT), which is responsible for the final step of caproate synthesis from caproyl-CoA. In the present study, two CoAT genes from Ruminococcaceae bacterium CPB6 and Clostridium tyrobutyricum BEY8 were identified by gene cloning and expression analysis. Enzyme assays and kinetic studies were carried out using butyryl-CoA or caproyl-CoA as the substrate. CPB6-CoAT can catalyze the conversion of both butyryl-CoA into butyrate and caproyl-CoA into caproate, but its catalytic efficiency with caproyl-CoA as the substrate was 3.8-times higher than that with butyryl-CoA. In contrast, BEY8-CoAT had only BCoAT activity, not CCoAT activity. This demonstrated the existence of a specific CCoAT involved in chain elongation via the reverse β-oxidation pathway. Comparative bioinformatics analysis showed the presence of a highly conserved motif (GGQXDFXXGAXX) in CoATs, which is predicted to be the active center. Single point mutations in the conserved motif of CPB6-CoAT (Asp346 and Ala351) led to marked decreases in the activity for butyryl-CoA and caproyl-CoA, indicating that the conserved motif is the active center of CPB6-CoAT and that Asp346 and Ala351 have a significant impact on the enzymatic activity. This work provides insight into the function of CCoAT in caproic acid biosynthesis and improves understanding of the chain elongation pathway for MCFA production.
Role of ACE2 in pregnancy and potential implications for COVID-19 susceptibility
Authors: Azinheira Nobrega Cruz Nayara , Stoll Danielle , Casarini Dulce Elena , Bertagnolli Mariane
Published: August 2021

In times of coronavirus disease 2019 (COVID-19), the impact of severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 infection on pregnancy is still unclear. The presence of angiotensin-converting enzyme (ACE) 2 (ACE2), the main receptor for SARS-CoV-2, in human placentas indicates that this organ can be vulnerable for viral infection during pregnancy. However, for this to happen, additional molecular processes are critical to allow viral entry in cells, its replication and disease manifestation, particularly in the placenta and/or feto–maternal circulation. Beyond the risk of vertical transmission, COVID-19 is also proposed to deplete ACE2 protein and its biological actions in the placenta. It is postulated that such effects may impair essential processes during placentation and maternal hemodynamic adaptations in COVID-19 pregnancy, features also observed in several disorders of pregnancy. This review gathers information indicating risks and protective features related to ACE2 changes in COVID-19 pregnancies. First, we describe the mechanisms of SARS-CoV-2 infection having ACE2 as a main entry door and current evidence of viral infection in the placenta. Further, we discuss the central role of ACE2 in physiological systems such as the renin–angiotensin system (RAS) and the kallikrein–kinin system (KKS), both active during placentation and hemodynamic adaptations of pregnancy. Significant knowledge gaps are also identified and should be urgently filled to better understand the fate of ACE2 in COVID-19 pregnancies and the potential associated risks. Emerging knowledge will be able to improve the early stratification of high-risk pregnancies with COVID-19 exposure as well as to guide better management and follow-up of these mothers and their children.
Anti-inflammatory cytokine-eluting collagen hydrogel reduces the host immune response to dopaminergic cell transplants in a rat model of Parkinson’s disease
Authors: Cabré Sílvia , Alamilla Verónica , Moriarty Niamh , Pandit Abhay , Dowd Eilís
Published: August 2021

In cell replacement approaches for Parkinson’s disease, the intracerebral implantation of dopamine neuron-rich grafts generates a neuroinflammatory response to the grafted cells that contributes to its varied outcome. Thus, the aim of the present study was to fabricate an anti-inflammatory cytokine-eluting collagen hydrogel capable of delivering interleukin (IL)-10 to the brain for reduction of the neuroinflammatory response to intracerebral cellular grafts. In vitro assessment revealed that cross-linker concentration affected the microstructure and gelation kinetics of the hydrogels and their IL-10 elution kinetics, but not their cytocompatibility or the functionality of the eluted IL-10. In vivo evaluation revealed that the hydrogels were capable of delivering and retaining IL-10 in the rat striatum, and reducing the neuroinflammatory (microglial) response to hydrogel-encapsulated grafts. In conclusion, IL-10-eluting collagen hydrogels may have beneficial anti-inflammatory effects in the context of cellular brain repair therapies for Parkinson’s disease and should be investigated further.
Minimum error entropy criterion‐based randomised autoencoder
Authors: Ma Rongzhi , Wang Tianlei , Cao Jiuwen , Dong Fang
Published: August 2021

The extreme learning machine‐based autoencoder (ELM‐AE) has attracted a lot of attention due to its fast learning speed and promising representation capability. However, the existing ELM‐AE algorithms only reconstruct the original input and generally ignore the probability distribution of the data. The minimum error entropy (MEE), as an optimal criterion considering the distribution statistics of the data, is robust in handling non‐linear systems and non‐Gaussian noises. The MEE is equivalent to the minimisation of the Kullback–Leibaler divergence. Inspired by these advantages, a novel randomised AE is proposed by adopting the MEE criterion as the loss function in the ELM‐AE (in short, the MEE‐RAE) in this study. Instead of solving the output weight by the Moore–Penrose generalised inverse, the optimal output weight is obtained by the fixed‐point iteration method. Further, a quantised MEE (QMEE) is applied to reduce the computational complexity of. Simulations have shown that the QMEE‐RAE not only achieves superior generalisation performance but is also more robust to non‐Gaussian noises than the ELM‐AE.
A hybrid level shifted carrier‐based PWM technique for modular multilevel converters
Authors: M Aswini Kumar , Gopi Anjana K. , Biswas Jayanta , Barai Mukti
Published: August 2021

This paper presents a hybrid level shifted carrier‐based pulse width modulation (HLSC‐PWM) technique for modular multilevel converters (MMCs). The concept of the proposed HLSC‐PWM method is developed by combining the principles of phase disposition PWM (PD‐PWM), phase opposition disposition PWM (POD‐PWM), and alternate phase opposition disposition PWM (APOD‐PWM) methods. The main aim of the proposed HLSC‐PWM method is to generate an output voltage with half‐wave and quarter‐wave symmetries. The generated symmetrical PWM output voltage based on the proposed HLSC‐PWM method provides less total harmonic distortion (THD) and enhances the DC‐Link voltage utilization (DCLVU). A generalized mathematical model is formulated to develop a single HLSC for MMC with an N number of submodules (SMs) per arm. Theoretical analysis of DCLVU for the proposed method is described. The functionality and performance of the HLSC‐PWM method are carried out on a three‐phase five‐level MMC in MATLAB/Simulink. A hardware prototype of a single‐phase five‐level MMC is designed for experimental validation. The proposed HLSC‐PWM method is implemented on an Altera/Cyclone I series (EP1C12Q240C8N) field‐programmable gate array (FPGA), simulation and experimental results are presented.
Study of different performance measures and their relations in satellite‐based and terrestrial quantum communication
Authors: Mukhopadhyay Avik , Kumar Borah Shantom , Sharma Yashkalp , Bitragunta Sainath , Chamola Vinay
Published: August 2021

Rapid developments in quantum communication are paving the way forward for more advanced technologies. Conventional channels like optical fibres have been a great resource in recent decades. However, they suffer largely from exponential transmissivity decays and are not suitable for very long‐distance communication. Satellite links along with quantum cryptography can be the foundation of modern quantum communication systems. This work presents an overview of the hybrid quantum repeater with a detailed analysis of different parametric relations in satellite‐based communication from experimental data. The link efficiency between the satellite‐based scheme and terrestrial scheme is also compared, emphasising the satellite‐based scheme's importance for quantum communication. Finally, we present a performance analysis of different quantities and derive relations between them.
Molecular gas and star formation within 12 strong galactic bars observed with IRAM-30 m
Authors: Díaz-García S. , Lisenfeld U. , Pérez I. , Zurita A. , Verley S. , Combes F. , Espada D. , Leon S. , Martínez-Badenes V. , Sabater J. , Verdes-Montenegro L.
Published: August 2021

Context.While some galactic bars show recent massive star formation (SF) along them, some others do not. Whether bars with low level of SF are a consequence of low star formation efficiency, low gas inflow rate, or dynamical effects remains a matter of debate.

Aims.In order to study the physical conditions that enable or prevent SF, we perform a multi-wavelength analysis of 12 strongly barred galaxies with total stellar masses log10(M⋆/M⊙)∈[10.2, 11], chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1–0) and CO(2–1) emission within bars with the IRAM-30 m telescope (beam sizes of 1.7–3.9 kpc and 0.9–2.0 kpc, respectively; 7–8 pointings per galaxy on average).

Methods.We estimated molecular gas masses (Mmol) from the CO(1–0) and CO(2–1) emissions. SF rates (SFRs) were calculated from GALEX near-ultraviolet (UV) and WISE 12 μm images within the beam-pointings, covering the full bar extent (SFRs were also derived from far-UV and 22 μm).

Results.We detect molecular gas along the bars of all probed galaxies. Molecular gas and SFR surface densities span the ranges log10(Σmol/[M⊙pc−2]) ∈ [0.4,2.4] and log10(ΣSFR/[M⊙pc−1kpc−2]]) ∈ [−3.25, −0.75], respectively. The star formation efficiency (SFE; i.e., SFR/Mmol) in bars varies between galaxies by up to an order of magnitude (SFE ∈[0.1, 1.8] Gyr−1). On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature (∼0.43 Gyr−1), regardless of whether we estimateMmolfrom CO(1–0) or CO(2–1). Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with the lowest SFE and ΣSFR(NGC 4548 and NGC 5850, SFE ≲ 0.25 Gyr−1, ΣSFR ≲ 10−2.25 M⊙yr−1kpc−2,M⋆ ≳ 1010.7 M⊙) are also those hosting massive bulges and signs of past interactions with nearby companions.

Conclusions.We present a statistical analysis of the SFE in bars for a sample of 12 galaxies. The SFE in strong bars is not systematically inhibited (either in the central, middle, or end parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work.
Bound mass of Dehnen models with a centrally peaked star formation efficiency
Authors: Shukirgaliyev B. , Otebay A. , Sobolenko M. , Ishchenko M. , Borodina O. , Panamarev T. , Myrzakul S. , Kalambay M. , Naurzbayeva A. , Abdikamalov E. , Polyachenko E. , Banerjee S. , Berczik P. , Spurzem R. , Just A.
Published: August 2021

Context. Understanding the formation of bound star clusters with a low star formation efficiency (SFE) is important for improving our knowledge of the star-formation history of galaxies. In N-body models of star-cluster evolution after gas expulsion, the Plummer model with an outer power law density profile has been used in a broad range of studies.

Aims. Here, we study the impact of the density profile slopes on the survivability of the low-SFE star clusters after instantaneous gas expulsion. We compare cases when a stellar cluster exhibits a Plummer profile to those with Dehnen profiles, including cuspy ones of different slopes at the time of formation.

Methods. We determined the corresponding density profile of the residual gas for a given global SFE, assuming that our model clusters formed with a constant efficiency per free-fall time and, hence, with a shallower density profile for the gas than that of the stars. We performed direct N-body simulations of evolution of clusters initially in virial equilibrium within the gas potential following gas removal.

Results. We find that the violent relaxation lasts no longer than 20 Myr, independently of the density profile power law slopes. Dehnen model clusters survive after violent relaxation with significantly lower SFEs when the global SFE measured within the Jacobi radius or within a half-mass radius. Dehnen γ = 0 model clusters show a similar final bound fraction with the Plummer model clusters if the global SFE is measured within ten scale radii. The final bound fraction increases with the γ values for a given global SFE.

Conclusions. We conclude that Dehnen clusters better resist the consequences of the violent relaxation that follows the instantaneous gas expulsion, as compared to the Plummer clusters. Therefore, the shallower the outer density slope of the low-SFE clusters, the better their prospects for survival after gas expulsion. Among the Dehnen clusters, we find that the steeper the inner slope, the higher the bound mass fraction that is retained, following the violent relaxation for a given global SFE.
Tele-Audiology: Ready or Not
Authors: Palmer Catherine V.
Published: August 2021

The use of various forms of tele-audiology exploded during the pandemic. This brief article provides tips and considerations for providing tele-audiology as we move beyond the pandemic. Importantly, audiologists need to document all forms of remote care including audio/visual, telephone (audio only), and email to support movement toward state licensing boards acknowledging that audiologists are qualified to provide this care and for insurers to support reimbursement for care provided via this mechanism. Educators will need to ensure that classroom and clinical education includes tele-audiology.
Polarized we trade? Intraparty polarization and US trade policy
Authors: Friedrichs Gordon M.
Published: August 2021

Research indicates that polarization has led to an increasing dispersion between moderate and more extreme voters within both parties. Intraparty polarization supposedly affects the nature of interparty competition as it creates political space for new political realignments and the rise of anti-establishment candidates. This article examines the extent and impact of intraparty polarization in Congress on US trade policy. Specifically, the article examines whether (and which) trade policy preferences are distributed within and between both parties, as well as how intraparty polarization has influenced the outcome of US trade negotiations. It is theorized that intraparty polarization causes crosscutting legislative coalitions around specific trade policies and political realignments around ideological factions, with consequences for the outcome of trade negotiations. By relying on a unique dataset of congressional letters and co-sponsorship legislation, the article first derives trade policy preferences from members of Congress and computes their ideological means. Two contemporary cases of US trade policy are examined: The Transpacific Partnership Agreement and the US–Mexico–Canada Agreement. Via a structured-focused comparison of both cases, the paper finally assesses under which combinations of preference-based and ideology-based intraparty polarization Congress manages to ratify trade agreements. Findings suggest that both parties are intrinsically polarized between free trade and fair trade preferences yet show variance in their degree of ideology-based intraparty polarization. These findings contribute to existing work on bipartisanship as well as factions in the foreign policy realm, as it shows under which circumstances legislators can build crosscutting coalitions around foreign policies.
High power density laser and wobbling technique improve welding technology in aluminum alloys
Authors: Avachat Sayali S.
Published: August 2021

A profitable approach to enhance welding quality of aluminum alloys while minimizing thermal defects and energy consumption
Emergent behaviors of Cucker–Smale flocks on the hyperboloid
Authors: Ahn Hyunjin , Ha Seung-Yeal , Park Hansol , Shim Woojoo
Published: August 2021

We study emergent behaviors of Cucker–Smale (CS) flocks on the hyperboloid Hd in any dimensions. In a recent work [Ha et al., J. Math. Phys. 61(4), 042701 (2020)], a first-order aggregation model on the hyperboloid was proposed and sufficient conditions for emergent dynamics were proposed in terms of initial configuration and system parameters. In this paper, we are interested in the second-order modeling of CS flocks on the hyperboloid. For this, we derive our second-order model from the abstract CS model on complete and smooth Riemannian manifolds via explicit identifications of geodesic and parallel transport. Velocity alignment has been shown by combining general velocity alignment estimates for the abstract CS model on manifolds and verifications of the a priori estimate of the second derivative of the energy functional. For the two-dimensional case H2, similar to the recent result by Ahn, Ha, and Shim [Kinet. Relat. Models 14(2), 323–351 (2021)], asymptotic flocking admits only two types of asymptotic scenarios, either convergence to a rest state or a state lying on the same plane (coplanar state). We also provide several numerical simulations to illustrate an aforementioned dichotomy on the asymptotic dynamics of the hyperboloid CS model on H2.
Lax connection and conserved quantities of quadratic mean field games
Authors: Bonnemain Thibault , Gobron Thierry , Ullmo Denis
Published: August 2021

Mean field games is a new field developed simultaneously in applied mathematics and engineering in order to deal with the dynamics of a large number of controlled agents or objects in interaction. For a large class of these models, there exists a deep relationship between the associated system of equations and the non-linear Schrödinger equation, which allows us to get new insights into the structure of their solutions. In this work, we deal with the related aspects of integrability for such systems, exhibiting in some cases a full hierarchy of conserved quantities and bringing some new questions that arise in this specific context.
Low-dimensional chaos in the single wave model for self-consistent wave–particle Hamiltonian
Authors: Gomes J. V. , de Sousa M. C. , Viana R. L. , Caldas I. L. , Elskens Y.
Published: August 2021

We analyze nonlinear aspects of the self-consistent wave–particle interaction using Hamiltonian dynamics in the single wave model, where the wave is modified due to the particle dynamics. This interaction plays an important role in the emergence of plasma instabilities and turbulence. The simplest case, where one particle (N=1) is coupled with one wave (M=1), is completely integrable, and the nonlinear effects reduce to the wave potential pulsating while the particle either remains trapped or circulates forever. On increasing the number of particles (N=2, M=1), integrability is lost and chaos develops. Our analyses identify the two standard ways for chaos to appear and grow (the homoclinic tangle born from a separatrix, and the resonance overlap near an elliptic fixed point). Moreover, a strong form of chaos occurs when the energy is high enough for the wave amplitude to vanish occasionally.