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Improving polarizability is an important strategy for designing high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials. The substitution of equivalent or aliovalent atoms can manipulate the polarizability by adjusting the symmetry of the polyhedron. Herein, the Li+ and Cd2+ are introduced into the Cu3PS4 as the equivalent and aliovalent dopants for the Cu site. As a result, Li+ can significantly improve the bandgap (Eg) of LixCu3−xPS4 from 2.38 to 2.88 eV, leading to a higher laser‐induced damage threshold (LIDT) of 4.9 times than AgGaS2 (AGS) with a comparable second harmonic generation (SHG) response of AGS (26−45 µm). Interestingly, Cd2+ can improve the SHG response and enlarge the Eg simultaneously. As a result, Cd0.4Cu2.2PS4 has a large SHG response of 10 × AGS at 2050 nm (26−45 µm) and a LIDT of 2.6 × AGS. Theoretical calculations reveal that lattice vacancies induced by Cd2+ significantly boost polarizability compared to LixCu3−xPS4 with no vacancy, leading to a strong NLO response. [ABSTRACT FROM AUTHOR]

Although orthorhombic GeSe is predicted to have an ultrahigh figure of merit, ZT ≈ 2.5, up to now, the highest experimental value is ≈0.2 due to the low carrier concentration (nH ≈ 1018 cm−3). Improving symmetry is an effective approach for enhancing the ZT of GeSe‐based materials. With Te‐alloying, Ge4Se3Te displays the two‐dimensional hexagonal structure and high nH ≈ 1.23 × 1021 cm−3. Interestingly, Ge4Se3Te transformed from the hexagonal into the rhombohedral phase with only ≈2% I–V–VI2‐alloying (I = Li, Na, K, Cu, Ag; V = Sb, Bi; VI = Se, Te). According to the calculated results of Ge0.82Ag0.09Bi0.09Se0.614Te0.386 single‐crystal grown via AgBiTe2‐alloying, it exhibits a higher valley degeneracy than the hexagonal Ge4Se3Te. For instance, AgBiTe2‐alloying induces a strong band convergence and band inversion effect, resulting in a significantly enhanced Seebeck coefficient and power factor with a similar nH from 17 µV K−1 and 0.63 µW cm−1 K−2 for pristine Ge4Se3Te to 124 µV K−1 and 5.97 µW cm−1 K−2 for 12%AgBiTe2‐alloyed sample, respectively. Moreover, the sharply reduced phonon velocity, nano‐domain wall structure, and strong anharmonicity lead to low lattice thermal conductivity. As a result, a record‐high average ZT ≈0.95 over 323–773 K with an excellent ZT ≈ 1.30 is achieved at 723 K. [ABSTRACT FROM AUTHOR]

This study investigates Ga‐doped n‐type PbTe thermoelectric materials and the dynamic phase conversion process of the second phases via Cu2Se alloying. Introducing Cu2Se enhances its electrical transport properties while reducing its lattice thermal conductivity (κlat) via weak electron–phonon coupling. Cu2Te and CuGa(Te/Se)2 (tetragonal phase) nanocrystals precipitate during the alloying process, resulting in Te vacancies and interstitial Cu in the PbTe matrix. At room temperature, Te vacancies and interstitial Cu atoms serve as n‐type dopants, increasing the carrier concentration and electrical conductivity from ≈1.18 × 1019 cm−3 and ≈1870 S cm−1 to ≈2.26 × 1019 cm−3 and ≈3029 S cm−1, respectively. With increasing temperature, the sample exhibits a dynamic change in Cu2Te content and the generation of a new phase of CuGa(Te/Se)2 (cubic phase), strengthening the phonon scattering and obtaining an ultralow κlat. Pb0.975Ga0.025Te‐3%CuSe exhibits a maximum figure of merit of ≈1.63 at 823 K, making it promising for intermediate‐temperature device applications. [ABSTRACT FROM AUTHOR]

From the dried root and rhizomes of Atalantia buxifolia afford 11 compounds, one new compound 1 and ten known compounds 2–11 were isolated and identified. The novel compound 1 was alkaloid glycoside. Its mother nuclear was the acridone, which was relatively rare. The structure of compound 1 was established identified by spectrum and elucidated as β-D-Glu-4,5-dimethoxy-1,6-dihydroxy-10-methyl-acridone. The compound 1 enriched the compound library and laid the material foundation for the subsequent study of pharmacological activities. [ABSTRACT FROM AUTHOR]

Improving polarizability is an important strategy for designing high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials. The substitution of equivalent or aliovalent atoms can manipulate the polarizability by adjusting the symmetry of the polyhedron. Herein, the Li+ and Cd2+ are introduced into the Cu3PS4 as the equivalent and aliovalent dopants for the Cu site. As a result, Li+ can significantly improve the bandgap (Eg) of LixCu3−xPS4 from 2.38 to 2.88 eV, leading to a higher laser‐induced damage threshold (LIDT) of 4.9 times than AgGaS2 (AGS) with a comparable second harmonic generation (SHG) response of AGS (26−45 µm). Interestingly, Cd2+ can improve the SHG response and enlarge the Eg simultaneously. As a result, Cd0.4Cu2.2PS4 has a large SHG response of 10 × AGS at 2050 nm (26−45 µm) and a LIDT of 2.6 × AGS. Theoretical calculations reveal that lattice vacancies induced by Cd2+ significantly boost polarizability compared to LixCu3−xPS4 with no vacancy, leading to a strong NLO response. [ABSTRACT FROM AUTHOR]

Three new phenolic compounds, acutacoside C (1), acutacoside D (2) and acutacoside E (3) were isolated from the aerial part of Argyreia acuta. The oligosaccharide chain was composed of two glucoses and three rhamnoses, and the aglycone was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). The core of the three compounds was operculinic acid B, which was rare in resin glycosides. Their structures were established by a combination of spectroscopic and chemical methods. Compounds 1-3 have been evaluated for inhibitory activity against α-glucosidase, which all showed weak inhibitory activities. From the aerial parts of Argyreia acuta, three new pentasaccharide compounds were isolated, identified and evaluated for their a-glucosidase inhibition activity. [ABSTRACT FROM AUTHOR]

Two new compounds of acutacosides 1 and 2, pentasaccharide resin glycosides were isolated from the aerial parts of Argyreia acuta. The core of the two compounds was operculinic acid A, and they were esterfied at the same position, just one substituent group was linked at C-2 of Rha. The absolute configuration of the aglycone in the two compounds was established by Mosher's method, which was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). Their structures were established by a combination of spectroscopic and chemical methods. [ABSTRACT FROM AUTHOR]

Context: Since AMP-activated protein kinase (AMPK) activation in skeletal muscle of obese rodents stimulates fatty acid oxidation, it is reasonable to hypothesize that pharmacological activation of AMPK might be of therapeutic benefit in obesity. Objective: To investigate the effects of the traditional Korean anti-obesity drug GGEx18, a mixture of three herbs, Laminaria japonica Aresch (Laminariaceae), Rheum palmatum L. (Polygonaceae), and Ephedra sinica Stapf (Ephedraceae), on obesity and the involvement of AMPK in this process. Materials and methods: After high fat diet-induced obese mice were treated with GGEx18, we studied the effects of GGEx18 on body weight, fat mass, skeletal muscle lipid accumulation, and the expressions of AMPK, peroxisome proliferator-activated receptor άά (PPARα), and PPARα target genes. The effects of GGEx18 and/or the AMPK inhibitor compound C on lipid accumulation and expression of the above genes were measured in C2C12 skeletal muscle cells. Results: Administration of GGEx18 to obese mice for 9 weeks significantly ( p < 0.05) decreased body and adipose tissue weights compared with obese control mice ( p < 0.05). Lipid accumulation in skeletal muscle was inhibited by GGEx18. GGEx18 significantly ( p < 0.05) increased skeletal muscle mRNA levels of AMPKα1 and AMPKα2 as well as PPARα and its target genes. Consistent with the in vivo data, GGEx18 inhibited lipid accumulation, and similar activation of genes was observed in GGEx18-treated C2C12 cells. However, compound C inhibited these effects in C2C12 cells. Discussion and conclusion: These results suggest that GGEx18 improves obesity through skeletal muscle AMPK and AMPK-stimulated expression of PPARα and its target enzymes for fatty acid oxidation. [ABSTRACT FROM AUTHOR]

Two new triterpenoids, 3-oxotirucalla-7,9(11),24-trien-21-oic acid (1) and 18Hα,3β,20β-ursanediol (2), along with 15 known triterpenes, α-amyrin, α-boswellic acid, β-boswellic acid, acetyl α-boswellic acid, acetyl β-boswellic acid, 9,11-dehydro-β-boswellic acid, 9,11-dehydro-α-boswellic acid, acetyl 11α-methoxy-β-boswellic acid, 11-keto-β-boswellic acid, acetyl 11-keto-β-boswellic acid, acetyl α-elemolic acid, 3β-hydroxytirucalla-8,24-dien-21-oic acid, elemonic acid, 3α-hydroxytirucalla-7,24-dien-21-oic acid, and 3α-hydroxytirucall-24-en-21-oic acid, were isolated from the resin of Boswellia carterii Birdw. [ABSTRACT FROM AUTHOR]

SnTe is an intriguing alternative to PbTe for midtemperature thermoelectric applications. Despite steady progress, its performance is lagging, in part because of the large energy difference(Δ E L-Σ ) between the light (L-band) and heavy (Σ-band) valence bands and higher lattice thermal conductivity (κ L ). Previous studies have shown that applying pressure can enhance the Seebeck coefficient ( S ) and power factor ( PF ) of SnTe. Inspired by this study, we showcase how the high-pressure effect can be emulated under ambient pressure by substituting Sn with atoms possessing smaller atomic radii. Specifically, Sb- and Ge-doping combined with CdTe- or CdS-alloying induce lattice shrinkage, also referred to as "chemical pressure", raising the energy of the Σ-band. Additionally, these substituted atoms lower the contribution of Sn 5s-Te 5p antibonding states to the L-band, thereby reducing its energy and dispersion. These combined effects decrease Δ E L-Σ from 0.36 to 0.09 eV, leading to the enhanced S and average PF avg . Notably, the PF avg , ranging from 323 to 873 K, increases from 8.1 μW cm -1 K -2 for pristine SnTe to 21.6 μW cm -1 K -2 for Sn 0.79 Ge 0.15 Sb 0.06 Te-5% CdTe. Furthermore, the intensified phonon scattering resulting from discordant nature of Ge and Cd atoms, creating point defects soften phonon modes, and the presence of Ge-rich nanoprecipitates lead to a substantial 62% reduction in κ L at 873 K. This strong valence band convergence and enhanced phonon scattering collectively contribute to a high peak ZT of 1.5 (873 K) and high average ZT avg = 0.81 over the temperature range of 323-873 K.

This study was purposed to clarify the difference of microRNA (miRNA) expression in the peripheral blood cells of patients with primary immune thrombocytopenia (ITP) and normal controls. Exqion miRCURY(TM) microarray was used to investigate differentially expressed miRNA of peripheral blood cells obtained from affected ITP patients and the healthy controls. Cluster analysis was used to identify miRNA expression profile between the ITP patients and the healthy controls. Real-time PCR was used for validation. The results showed that a total of 159 miRNA were found to be differentially expressed in ITP patients compared to the controls, with 79 up-regulated and 80 down-regulated. Based on these differentially expressed miRNA, a tree with clear distinction between the controls and ITP patients was generated by cluster analysis. Real-time PCR confirmed microarray analysis results. It is concluded that differentially expressed miRNA were found in the peripheral blood cells from ITP patients, which may be potential novel biomarkers for ITP as well as help to elucidate pathogenic mechanisms of ITP.

Objective: To clone and express the gene of Hgp44 in adhesin domains of gingipains from Porphyromonas gingivalis (Pg) and to purify the protein., Methods: The genomic DNA of Pg was isolated from PgATCC33277. The Hgp44 gene fragment was amplified by polymerase chain reaction (PCR) and then inserted into the cloning vector pMD18-T and sequenced. The correct fragment was linked with a prokaryotic expression vector pET-22b to construct the recombinant expression plasmid pET22b-Hgp44. The pET22b-Hgp44 confirmed by enzyme digestion was transformed into competent Escherchia coli (Ec) BL21 (DE3) cells. Expression of fusion protein was induced by isopropyl-β-D-thiogalactoside (IPTG), and purified by immobilized metal-chelating affinity chromatography (IMAC) using a Ni(2+) matrix column. SDS-polyaerylamide gel electrophoresis (SDS-PAGE) and Western blotting analysis were used to examine the fusion protein., Results: A 1 100 bp fragment was successfully amplified and verified by the agarose gel electrophoresis and sequencing. The generated recombinant expression vectors pET22b-Hgp44 were verified by enzyme digestion and agarose gel electrophoresis. The expression of fusion protein in Ec BL21 (DE3) cells was examined by SDS-PAGE and Western blotting analyses, and the data showed that the protein was 44 000 in size and expressed mostly in the form of inclusion body. The purification of fusion protein was achieved using Ni(2+) affinity chromatography. About 3.5 mg/L fusion protein was obtained., Conclusions: Hgp44 was successfully expressed in the prokaryotic expression system and purified by IMAC using a Ni(2+) matrix column.

Objective: To establish a method used for optimization of harvesting time and determine the best time for harvesting Rumex gmelini., Method: An HPLC method was applied to determinate the contents of seven active constituents(resveratrol, polydatin, chrysophanol 1-glucoside, nepodin, emodin, chrysophanol and physcion)of R. gmelini at different development stage. The result was analyzed by principal component analysis., Result: The accumulation of active constituents showed a regular pattern., Conclusion: The best harvesting time of R. gmelini is early July.