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Synthesis of celastrol derivatives as potential non-nucleoside hepatitis B virus inhibitors

CHEMICAL BIOLOGY & DRUG DESIGN 2020年第6期96卷 1380-1386页

作者： Zhang, He Lu, Gongxi Beijing BeiqinBiotech Co Ltd Xinggu Econ Dev Zone Beijing 101200 Peoples R China

A series of para-quinone methide (pQM) moiety and C-20- modified derivatives of celastrol were synthesized and evaluated for their inhibitory effect on the secretion of HBsAg and HBeAg as well as the inhibitory effect against HBV DNA replication. The results suggested that amidation of C-20 carboxylic group could generate derivatives with good anti-HBV profile, among them compound14showed the best inhibitory activity on the secretion of HBsAg (IC50 = 11.9 mu mu) and HBeAg (IC50 = 13.1 mu mu) with SI of 3.3 and 3.0, respectively. In addition,14also showed potent inhibitory effect against HBV DNA replication (48.5 +/- 15.1%, 25 mu M). This is, to our knowledge, the first report of celastrol derivatives as potential non-nucleoside HBV inhibitors.

关键词： celastrol hepatitis virus B inhibitor Tripterygium wilfordii Hook f

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Martensitic transformation and elastocaloric effect of Co51.5+xV31.5-xGa17 (x=0.1, 0.2, 0.3) alloys

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INTERMETALLICS 2021年 139卷 107348-107348页

作者： He, Jing Wei, Zhiyang Sun, Wen Lu, Xiang Ma, Shengcan Liu, Jian Jiangxi Univ Sci & Technol Fac Mat Met & Chem Jiangxi Key Lab Rare Earth Magnet Mat & Devices Ganzhou 341000 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn CAS Key Lab Magnet Mat & Devices Ningbo 315201 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn Zhejiang Prov Key Lab Magnet Mat & Applicat Techn Ningbo 315201 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Jiangxi Univ Sci & Technol Coll Rare Earths Ganzhou Key Lab Rare Earth Magnet Funct Mat & Phy Ganzhou 341000 Peoples R China

Co-V-Ga alloy, a newly discovered multifunctional material based on martensitic transformation (MT), has promising application prospects in spintronics and solid-state refrigeration fields. In this work, we investigated the MT behaviors and the elastocaloric effect (eCE) of Co51.5+xV31.5-xGa17 (x = 0.1, 0.2, 0.3) alloys. The alloys undergo a MT from paramagnetic austenite to paramagnetic martensite, accompanying by a large latent heat (about 6-9 J g-1). The MT temperature increases with the increase of the ratio of Co to V. The digital image correlation (DIC) combined with infrared thermography (IR) techniques were utilized to in situ characterize the stress-induced MT and temperature change of the sample. for the sample of x = 0.2, at a testing temperature of 301 K, it heats with a giant adiabatic temperature change up to 13.4 K upon loading, while cools only 2.4 K when stress releasing, showing an irreversible eCE. Raising the test temperature (319, 327 and 333 K) can greatly improve the reversibility of the eCE. Such an asymmetric elastocaloric temperature change at 301 K is closely related to the irreversibility of stress-induced MT, which can be attributed to several factors including the selfcooling effect, heat dissipative mechanism and the valence bond structure of Co-V-Ga alloys.

关键词： A functional alloys B Martensitic transformation Elastocaloric effect f Digital image correlation

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Bio-production of silica nanoparticles from rice husk and their impact on rice bakanae disease and grain yield

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ARCHIVES Of PHYTOPATHOLOGY AND PLANT PROTECTION 2020年第9-10期53卷 459-478页

作者： Elamawi, Rabab M. Tahoon, Abdelaziz M. Elsharnoby, Dalia E. El-Shafey, Rabie A. Agr Res Ctr Plant Pathol Res Inst Rice Pathol Dept Sakha 33717 Kafrelsheikh Egypt Agr Res Ctr Field Crops Res Inst Rice Res & Training Ctr Kafrelsheikh Egypt

The present study aimed to use silica nanoparticles for bakanae disease management after appearance of symptoms. Preparation of silica nanoparticles from milled and/or acid leaching rice husk prior to calcination were estimated to determine optimal methods. Characterisation using XRD, TEM and DLS showed amorphous SiNPs with high purity, sphere particles with diameter of 15 nm and stability of SiNPs, respectivelly. At laboratory, SiNPs led to significant reductions in sporulation of fusarium fujikuroi. In contrast, mycelial growth and colony-forming units (CfU) were increased. At greenhouse, Disease Severity Index (DSI) decreased with application of different SiNPs concentrations as seed treatment. SiNPs at 50 mg/L improved rice plants silica content, electrolyte leakage and peroxidase activity. At field, foliar application of SiNPs after disease symptoms appearance significantly reduced the disease incidence and increased grain yield. The current results suggested that controlling f. fujikuroi once appearing of bakanae disease symptoms considered a new effective management practices.

关键词： Silica nanoparticles f fujikuroi Disease Severity Index foliar application silica content electrolyte leakage and peroxidase activity

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Two Strawsonian strategies for accounting for morally responsible agency

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PHILOSOPHICAL STUDIES 2020年第8期177卷 2341-2364页

作者： Beglin, David Univ Calif Los Angeles Los Angeles CA 90095 USA

It is common for theorists, drawing on P. f. Strawson, to account for morally responsible agency in terms of the nature of the emotions and feelings that characterize our responsibility practices, in terms of the nature of the so-called "reactive attitudes." Here, I argue against this attitude-based Strawsonian strategy, and I argue in favor of an alternative, which I call the "concern-based Strawsonian strategy." On this alternative, rather than account for morally responsible agency in terms of the nature of the reactive attitudes, one accounts for such agency in terms of the concern that leaves us susceptible to those attitudes in the first place. This, I believe, is a more promising way to develop the Strawsonian approach than the attitude-based strategy. The concern-based strategy allows us to better countenance the number and variety of the reactive attitudes that characterize our responsibility practices;it shares the attitude-based strategy's virtues;and it seems to position us to better understand the distinctive social and moral significance associated with being and being regarded as a morally responsible agent.

关键词： P f Strawson Responsibility Moral psychology free will Agency Reactive attitudes

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Precipitation morphology and kinetics of T-Al6Mg11Zn11 intermetallic phase in Al-Mg-Zn ternary alloys

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INTERMETALLICS 2021年 139卷 107364-107364页

作者： Takata, Naoki Takagi, Rikito Li, Ruoqi Ishii, Hiroki Suzuki, Asuka Kobashi, Makoto Nagoya Univ Grad Sch Engn Dept Mat Proc Engn Chikusa Ku Furo Cho Nagoya Aichi 4648603 Japan

This study was undertaken to understand the fundamentals of T-Al6Mg11Zn11 intermetallic phase precipitation in heat-resistant Al-Mg-Zn ternary alloys, with the goal of further strength improvements. The thermodynamic assessment involved three alloy compositions, Al-4Mg-4.5Zn, Al-5Mg-3.5Zn, and Al-7Mg-1.5Zn (at%), with the T phase in a fixed fraction (approximately 6-7.5%) in equilibrium with the alpha-Al phase at 300 degrees C. The alloy compositions were set on different tie-lines between the alpha-Al and T phases in the two-phase region, resulting in varied compositions of each phase. In the three experimental alloys aged at 300 degrees C, the T phase precipitated on the grain boundaries of the alpha-Al matrix, and granular precipitates were homogeneously dispersed intragranularly. There was no significant difference in the precipitation morphology. It was demonstrated that the lattice parameters of the T and alpha-Al phases could be controlled based on the alloy composition and applied heat treatments. However, the lattice parameters have no significant effect on the precipitation morphologies of the thermodynamically stable T phase in the Al-Mg-Zn ternary alloys. The Zn-rich Al-4Mg-4.5Zn alloy exhibited a pronounced softening behavior after 10 h of aging due to the enhanced coarsening of precipitates in the alpha-Al matrix. The thermal instability of the precipitates was responsible for the transformation sequence from the initially formed metastable phases (eta-Zn2Mg associated phases) to the stable T phase. These results provided a fundamental insight that alloy strengthening by introducing thermodynamically stable intermetallic phases is essential for sustaining the strength of heat-resistant Al-Mg-Zn ternary alloys after long-term treatment at elevated temperatures.

关键词： A intermetallics (aluminides Silicides) B age-hardening Alloy design C heat treatment D microstructure E phase stability Prediction f electron microscopy Transmission G automotive uses Including engines (and other transportation uses)

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Whatever happened to reversion?

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STUDIES IN HISTORY AND PHILOSOPHY Of SCIENCE 2022年 92卷 97-108页

作者： Pence, Charles H. Catholic Univ Louvain Inst Super Philosoph Pl Cardinal Mercier 14Bte L3-06-01 B-1348 Louvain La Neuve Belgium

The idea of 'reversion' or 'atavism' has a peculiar history. for many authors in the late-nineteenth and early twentieth centuries - including Darwin, Galton, Pearson, Weismann, and Spencer, among others - reversion was one of the central phenomena which a theory of heredity ought to explain. By only a few decades later, however, fisher and others could look back upon reversion as a historical curiosity, a non-problem, or even an impediment to clear theorizing. I explore various reasons that reversion might have appeared to be a central problem for this first group of figures, focusing on their commitment to a variety of conceptual features of evolutionary theory;discuss why reversion might have then ceased to be an interesting phenomenon;and, finally, close with some more general thoughts about the death of scientific problems.

关键词： Reversion Atavism Charles Darwin francis Galton Karl Pearson W f R Weldon A fisher

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Periodic and aperiodic contributions to theta-beta ratios across adulthood

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PSYCHOPHYSIOLOGY 2022年第11期59卷 14113-14113页

作者： finley, Anna J. Angus, Douglas J. van Reekum, Carien M. Davidson, Richard J. Schaefer, Stacey M. Univ Wisconsin Ctr Hlth Minds Madison WI USA Bond Univ Sch Psychol Gold Coast Qld Australia Univ Reading Sch Psychol & Clin Language Sci Reading Berks England

The ratio of fronto-central theta (4-7 Hz) to beta oscillations (13-30 Hz), known as the theta-beta ratio, is negatively correlated with attentional control, reinforcement learning, executive function, and age. Although theta-beta ratios have been found to decrease with age in adolescents and young adults, theta has been found to increase with age in older adults. Moreover, age-related decrease in individual alpha peak frequency and flattening of the 1/f aperiodic component may artifactually inflate the association between theta-beta ratio and age. These factors lead to an incomplete understanding of how theta-beta ratio varies across the lifespan and the extent to which variation is due to a conflation of aperiodic and periodic activity. We conducted a partially preregistered analysis examining the cross-sectional associations between age and resting canonical fronto-central theta-beta ratio, individual alpha peak frequency, and aperiodic component (n = 268;age 36-84, M = 55.8, SD = 11.0). Age was negatively associated with theta-beta ratios, individual peak alpha frequencies, and the aperiodic exponent. The correlation between theta-beta ratios and age remained after controlling for individual peak alpha frequencies, but was nonsignificant when controlling for the aperiodic exponent. Aperiodic exponent fully mediated the relationship between theta-beta ratio and age, although beta remained significantly associated with age after controlling for theta, individual peak alpha, and aperiodic exponent. Results replicate previous observations and show age-related decreases in theta-beta ratios are not due to age-related decrease in individual peak alpha frequencies but primarily explained by flattening of the aperiodic component with age.

关键词： 1 f aging beta individual peak alpha frequency theta theta-beta ratio

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Synthesis and (fluoro)solvatochromism of two 3-styryl-2-pyrazoline derivatives bearing benzoic acid moiety: A spectral, crystallographic and computational study

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JOURNAL Of MOLECULAR LIQUIDS 2021年 331卷 115737-115737页

作者： Matiadis, Dimitris Nowak, Katarzyna E. Alexandratou, Eleni Hatzidimitriou, Antonios Sagnou, Marina Papadakis, Raffaello Natl Ctr Sci Res Demokritos Inst Biosci & Applicat Athens 15310 Greece Uppsala Univ Dept Chem Angstrom S-75120 Uppsala Sweden Univ Lodz Fac Biol & Environm Protect Dept Mol Biophys Pomorska St 141-143 PL-90236 Lodz Poland Natl Tech Univ Athens Sch Elect & Comp Engn Lab Biomed Opt & Appl Biophys Zografou Campus Athens 15780 Greece Aristotle Univ Thessaloniki Dept Chem Lab Inorgan Chem Thessaloniki 54124 Greece

In this work we report the synthesis of two fluorescent 2-pyrazoline derivatives exhibiting remarkable (fluoro) solvatochromic behavior. The pyrazolines were synthesized in one step from the corresponding monocarbonyl curcuminoids and 4-hydrazinobenzoic acid in high yield and purity and were fully characterized by means of NMR and fT-IR spectroscopy and HRMS spectrometry. The structure of the novel derivative 2was also characterized by means of X-ray crystallography. Both compounds were studied computationally in the gas phase. Additionally, the effects of solvent polarity on the absorption and fluorescence spectra of these derivatives were investigated in a solvent group consisting of various neat molecular solvents exhibiting hydrogen bond donating (HBD), hydrogen bond accepting (HBA), and/or dipolar behavior. The solvent effects observed were quantified and rationalized by employing suitable multiparametric Linear Solvation Energy Relationships (LSERs) involving dipolarity, HBD-acidity and HBA-basicity terms. The contribution of each of these parameters provided insights on the predominant solute-solvent interactions occurring in solution. Importantly, some differences in the (fluoro)solvatochromic aptitude/behavior were revealed among the derivatives and they were rationalized on the basis of their structural diversity. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Symbol/Abbreviation Meaning/definition A Onsager's Cavity term α HBD-acidity term in KAT equation a Coefficient of α term β HBA-basicity term in KAT equation b Coefficient of β term c 0 Speed of light in vacuum %C( i ) Relaltive contribution of parameter i δ NMR Chemical shift Δ v ~ v ~ abs − v ~ em ε Relative permittivity ε Molar extinction coefficient ε 0 Absolute permittivity of vacuum E f Maximum fluorescence energy E T H Maximum transition energy (high energy feature see Table 5) E T L Maximum transition energy (low energy feature see Table 5) E T (30) Reichardt's polarity scale f ( ε , n ) Solvent Polarity function involved in Lippert–Mataga model (Eq. 6) g ( ε , n ) Solvent Polarity function involved in Bilot–Kawski model (Eq. 10) h Planck's constant HBA Hydrogen Bond Acceptor HBD Hydrogen Bond Donor KAT Kamlet Abboud Taft (Equation) log ε Logarithm of Molar extinction coefficient LSER Linear Solvation Energy Relation μ e Dipole moment of the excited state μ g Dipole moment of the ground state v ~ f fluorescence maximum wavenumber v ~ abs Absorption maximum wavenumber n Refractive index π Dipolarity/polarizability term in KAT equation r Square root of the correlation coefficient R f Retention factor (TLC) r Si Relative contribution of parameter i rse Residual Sum of Squeres σ Hammett's substituent parameter s Coefficient of π term Σ v ~ v ~ em + v ~ ex S ap Aprotic solvent S p Protic Solvent φ ( ε , n ) Solvent Polarity function involved in Bilot–Kawski model (Eq. 9)

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Comparing the Effects of N and P Deficiency on Physiology and Growth for fast- and Slow-Growing Provenances of fraxinus mandshurica

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fORESTS 2021年第12期12卷 1760页

作者： Zhao, Xingtang Zhang, Xu Liu, Zhang Lv, Yipin Song, Tingting Cui, Jinghong Chen, Tianchi Li, Jianxia Zeng, fansuo Zhan, Yaguang Northeast Forestry Univ Natl Key Lab Tree Genet & Breeding Harbin 150040 Peoples R China Northeast Forestry Univ Coll Life Sci Harbin 150040 Peoples R China Northeast Forestry Univ Heilongjiang Touyan Innovat Team Program Tree Genet & Breeding Innovat Harbin 150040 Peoples R China

With the continuous increase in atmospheric carbon dioxide emissions, nitrogen (N) and phosphorus (P) as mineral elements increasingly restrict plant growth. To explore the effect of deficiency of P and N on growth and physiology, fraxinus mandshurica (hereafter "f. mandshurica") Rupr. annual seedlings of Wuchang (WC) provenance with fast growth and Dailing (DL) provenance with slow growth were treated with complete nutrition or starvation of N (N-), P (P-) or both elements (NP-). Although P- and N- increased the use efficiency of P (PUE) and N (NUE), respectively, they reduced the leaf area, chlorophyll content and activities of N assimilation enzymes (NR, GS, GOGAT), which decreased the dry weight and P or N amount. The free amino acid content and activities of Phosphoenolpyruvate carboxylase (PEPC) and acid phosphatase enzymes were reduced by N-. The transcript levels of NRT2.1, NRT2.4, NRT2.5, NRT2.7, AVT1, AAP3, NIA2, PHT1-3, PHT1-4 and PHT2-1 in roots were increased, but those of NRT2.1, NRT2.4, NRT2.5, PHT1-3, PHT1-4, PHT2-1 and AAP3 in leaves were reduced by P-. WC was significantly greater than DL under P- in dry weight, C amount, N amount, leaf area, PUE, NUE, which related to greater chlorophyll content, PEPC enzyme activity, N assimilation enzyme activities, and transcript levels of N and P transporter genes in roots and foliage, indicating a greater ability of WC to absorb, transport and utilize N and P under P-. WC was also greater than DL under N- in terms of the above indicators except the transcript levels of N and P assimilation genes, but most of the indicators did not reach a significant level, indicating that WC might be more tolerant to N- than DL, which requires further verification. In summary, WC was identified as a P-efficient provenance, as the growth rate was greater for the genetic type with high than low tolerance to P-.

关键词： nitrogen phosphorus carbon physiology f mandshurica

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Spaceflight breeding could improve the volatile constituents of Andrographis paniculata

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INDUSTRIAL CROPS AND PRODUCTS 2021年 171卷 113967-113967页

作者： Xia, Pengguo Li, Qianqian Liang, Zongsuo Zhang, Xuemin Yan, Kaijing Zhejiang Sci Tech Univ Coll Life Sci & Med Key Lab Plant Secondary Metab & Regulat Zhejiang Hangzhou 310018 Peoples R China Tasly Pharmaceut Grp Co Ltd Tianjin 300410 Peoples R China

The seeds of Andrographis paniculata carried by the Chinese recoverable satellite named "Chang Zheng", "Shen Zhou" and from the parallel ground-based seeds were selected as the samples. Seeds were flown under the space condition for 22 h and 33 days respectively. After returning to earth, the seeds carried by the different satellites and the parallel-ground control were cultivated for three consecutive generations under the same conditions. In this study, a chromatogram was obtained and contents of the volatile constituents in the samples were investigated on a gas chromatography-mass spectrometry (GC-MS). In addition, the main components of A. paniculata were analyzed by principal component analysis (PCA) and the relationship between four different strains and different generations of A. paniculata was evaluated by hierarchical cluster analysis (HCA) based on contents (%) of volatile constituents in A. paniculata. The results not only showed that displayed the contents of the volatile compounds (2-methyl-butanal, 3-methyl-butanal, 2-methyl-propanal) increasing with the number of generations in the spaceflight samples but showed the variation of the kinds of volatile constituents. The changes in the kind of volatile components of A. paniculata after spaceflight were firstly reported. There were 43 chemical constituents, which included aldehydes, acids, furans, ketones and alcohols were identified according to their mass spectra determined in both negative and positive ion modes. The CK and H118, D85 and H99 strains exhibited high similarity of volatile composition. The research provided the scientific data for spaceflight breeding of medicinal plants and indicated that space technology may be a new and effective way for the breeding and cultivation of A. paniculata.

关键词： Spaceflight Volatile constituents GC-MS HCA PCA Andrographis paniculata (Burm f ) Nees

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