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Six new polyoxygenated seco-cyclohexenes, artahongkongenes A–F ( 1–6 ), together with six known analogues ( 7–12 ) were isolated from the stems and leaves of Artabotrys hongkongensis . Their structures were elucidated by extensive spectroscopic methods. All new compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro . New seco-cyclohexenes 1–6 showed significant inhibitory effects against various human cancer cell lines with IC 50 values ranging from 0.26 to 16.58 μM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel eye-sensitive Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :Tb3+/Mn4+ were synthesized by simple co-precipitation strategy. • Red phosphor presents extremely strong ZPL at ∼ 625 nm and high color purity. • Red and green phosphors exhibit inherently outstanding thermal stability and moisture resistance. • Red and green phosphors coated directly on UV chip can achieve white emission. • The fabricated WLED devices show excellent electroluminescent properties. Novel eye-sensitive Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :Tb3+ green and Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :Mn4+ red oxyfluoride phosphors with extremely strong absorption in the UV region were designed and synthesized by simple co-precipitation strategy. Particularly, Tb3+ ions were doped in this matrix for the first time, which greatly improves their absorption efficiency in the near ultraviolet region (367 nm) and emits sharp green light (544 nm). In addition, the Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :Mn4+ red phosphors have strong zero phonon line (ZPL) emission at 625 nm, which is conducive to improving the sensitivity of human eye and color purity. Meanwhile, the optical properties of the red phosphor are significantly enhanced via doping K+ cations as charge compensators. Crystal field environment and nephelauxetic effect of the as-prepared phosphors before and after K+ cation doping were systematically analyzed. Moreover, these synthesized red/green phosphors have good thermal stability and moisture resistance. Remarkably, the as-prepared Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :5%Mn4+ or K 0.9 Ba 2.1 Nb 2 O 2 F 12 (H 2 O) 2 :5%Mn4+ red phosphors can be directly mixed with the as-synthesized Ba 3 Nb 2 O 2 F 12 (H 2 O) 2 :13%Tb3+ green phosphor coating on 365 nm near-ultraviolet LED chip to package WLED devices with excellent electroluminescence performance. These findings are conducive to opening an avenue for screening the unique structure of optical materials. [ABSTRACT FROM AUTHOR]

Abstract: In plants, ZnF-AN1 genes are part of a multigene family with 13 members in Arabidopsis thaliana, 19 members in Populus trichocarpa, 17 members in Oryza sativa, at least 11 members in Zea mays, and 2 members in Chlamydomonas reinhardtii. All ZnF-AN1 genes contain the ZnF-AN1 domain. According to the phylogenetic analysis of the ZnF-AN1 domain, we divided plant ZnF-AN1 genes into two types. The coding sequences of most type I members do not possess any introns, while most type II members do possess intron(s). Through Northern blot analysis of maize members and digital Northern analysis of Arabidopsis members, we found that most ZnF-AN1 genes are involved in responses to abiotic stresses. The evolutionary analysis indicated that the expansion rate of type I was higher than that of type II. After expansion, some ZnF-AN1 genes may have gained new functions, some may have lost their functions, and some were specialized to perform their functions in stress-specific or tissue-specific modes. In addition, we propose an evolutionary model of type II ZnF-AN1 genes in plants. [Copyright &y& Elsevier]

Mate choice copying refers to an agent copying the choice for a potential sexual/romantic partner made by a relevant model and has been observed across many species. This study investigated the neural profiles of two copying strategies in humans – acceptance and rejection copying – using functional magnetic resonance imaging (fMRI). Female participants observed female models accepting, rejecting, or being undecided about (control), males as potential romantic partners before and after rating their own willingness to choose the same males. We found that observing acceptance shifted participants' own choices towards acceptance, while observing rejection shifted participants' choices towards rejection. A network of motivation-, conflict- and reinforcement learning related brain regions was activated for observing the models' decisions. The rostral anterior cingulate gyrus (rACCg) and the caudate in particular were activated more strongly when observing acceptance. Activation in the inferior parietal lobe directly scaled with the magnitude of changes in choices after observing acceptance, while activation in the ACCg also scaled with changes after observing rejection. These findings point to partly dissociable neural profiles for copying strategies that might be linked to different contributions of incentive-driven and vicarious motivation, potentially reflecting the presence or absence of internalised reward experiences. [ABSTRACT FROM AUTHOR]

[Display omitted] Fine-tuning the surface structure of transition metal oxides at the atomic level is a promising way to improve the catalytic properties of materials. However, the influence of crystal surface structure on electrode reaction kinetics is still limited. In this study, we propose an in-situ synthesis strategy to obtain two-dimensional carbon/cerium oxide core–shell nanosheets by thermal decomposition of Ce-MOF nanosheets grown on the surface of carbon nanostructures, and fine-tuning the surface structure by introducing oxygen vacancies through defect engineering during the oxide nucleation process is conducted to obtain controllable exposed {1 1 1} and {1 1 0} surface CeO 2 @C composites. Both experiments and theoretical calculations show that the {1 1 0} -dominated nanocomplex (CeO 2 @C-350S) has better kinetic behavior and catalytic activity due to its abundant surface defects, which is manifested in higher active surface area, richer carrier concentration, and better promotion of diffusion and adsorption. In addition, CeO 2 @C-350S electrode has an extremely wide linear range and good stability in the electrochemical detection of nitrite. After 1000 times of the accelerated cycle experiments, CeO 2 @C-350S electrode still maintains 79.3 % of its initial current response, and recovers to 87.3 % after 10 min of stopping the test. The electrode stability is excellent, which is attributed to the clever carbon shell structure of the material. This synthesis strategy can be extended to other carbon-based oxide composite catalysts to improve the electrocatalytic performance and overall stability by adjusting the surface structure. [ABSTRACT FROM AUTHOR]

A hierarchical virtual screening was applied to identify natural products as new prototypes of PTP1B inhibitors. Ten compounds exhibited IC 50 values at the micromolar level, and nine of them demonstrated evident selectivity to PTP1B over four other PTPs. • Natural hits were identified as PTP1B inhibitors by virtual screening. • Ten hits demonstrated excellent potency with IC 50 at micromolar level against PTP1B. • Several hits showed evident selectivity to PTP1B over four other PTPs, including TCPTP. • A linear furancoumarin skeleton was recognized as a new prototype for PTP1B inhibitors. Protein tyrosine phosphatase 1B (PTP1B) is emerging as a promising yet challenging target for drug discovery. To identify natural products as new prototypes for PTP1B inhibitors, we employed a hierarchical protocol combining ligand-based and structure-based approaches for virtual screening against natural product libraries. Twenty-six compounds were prioritized for enzymatic evaluation against PTP1B, and ten of them were recognized as potent PTP1B inhibitors with IC 50 values at the micromolar level. Notably, nine compounds demonstrated evident selectivity to PTP1B over four other PTPs, including the most homologous T -cell protein tyrosine phosphatase (TCPTP). The results implicated that the structural uniqueness of the natural products might be a potential solution to the selectivity issue associated with the target PTP1B. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow sphere structure of poly(ionic liquid)s (HPILs) was fabricated as nanoreactor. • HPILs nanoreactor efficiently enhanced the activity of metal catalysts and showed high selectivity of AA. • HPILs could storage and stabilize catalysts during reaction with high activity for 7 times. • HPILs could promote the generation of free radicals to enhance the reaction. • The reaction process of HPILs was theoretically calculated to verify high activity and selectivity. Hollow structure nanoreactors take advantage of catalyst loading and enhanced activity by shell construction. In this work, functionalized poly(ionic liquid)s (PILs) with hollow spherical structures were synthesized by polymerization- and quaternization-based approaches. These hollow structure PILs (HPILs) could be controllable designed from IL monomer easily, giving HPILs various properties. In the subsequent selective oxidation of cyclohexane, the HPILs acting as nanoreactors could efficiently improve the activity of metal salt catalysts (CoCl 2) and displayed adjustable selectivity for cyclohexanone, cyclohexanol (KA) or adipic acid (AA) by different types of HPILs. In kinetic study, it follows first-order reaction kinetics which CoCl 2 /HPIL-C12 had a lower the activation energy of 29.1 kJ/mol. Importantly, these nanoreactors storing the catalysts could be recovered and reused more than 7 times without significant loss of activity. A theoretical model for the hollow spherical reactor was further established to support the advance of the HPILs reactor, which could also help to predict reaction process in other core-shell catalytic system. Due to controlled substrate transfer and enhanced radical generation in HPILs, the reaction process could be adjusted to enhance the conversion of cyclohexane and selective oxidation to AA. [ABSTRACT FROM AUTHOR]

Two novel γ -lactone derivatives, trigoheterophines A ( 1 ) and B ( 2 ), together with four known furan derivatives ( 3 – 6 ), were isolated from the stems and leaves of Trigonostemon heterophyllus . The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparing with the data reported in literature. Among them, trigoheterophines A ( 1 ) and B ( 2 ) represent an unusual type of γ -lactone derivatives, possessing 21 carbon atoms on the carbon skeleton, and known compouds ( 3 – 6 ) are rare furan derivatives in the plant kingdom with diverse long-chain hydrocarbyl groups as substituents at C-4. All isolated compounds were evaluated for their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro . Compounds 1 – 6 showed significant antiproliferative effects against various human cancer cell lines with IC 50 values ranging from 0.28 to 12.06 μM. These findings suggest that the discoveries of these novel γ -lactone derivatives and furan derivatives with significant antiproliferative activities isolated from T. heterophyllus could be of great importance to the development of new anticancer agents. [ABSTRACT FROM AUTHOR]

[Display omitted] PTP1B plays an important role as a key negative regulator of tyrosine phosphorylation associated with insulin receptor signaling in the therapy for diabetes and obesity. In this study, the anti-diabetic activity of dianthrone derivatives from Polygonum multiflorum Thunb., as well as the structure–activity relationships, mechanism, and molecular docking were explored. Among these analogs, trans -emodin dianthrone (compound 1) enhances insulin sensitivity by upregulating the insulin signaling pathway in HepG2 cells and displays considerable anti-diabetic activity in db/db mice. By using photoaffinity labeling and mass spectrometry-based proteomics, we discovered that trans -emodin dianthrone (compound 1) may bind to PTP1B allosteric pocket at helix α6/α7, which provides fresh insight into the identification of novel anti-diabetic agents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six new oligostilbenes obtained from the stems of Caragana sinica. • Natural tetrastilbenes were determined as absolute configuration for the first time. • Obvious inhibition of α -glucosidase in vitro with IC 50 values of 0.1 ∼ 0.4 μ M. • Leachianol (7) showed significant inhibition (88.8%, 10 μ M) of protein tyrosine phosphatase (PTP1B) with IC 50 value of 1.1 μ M in vitro. Six new oligostilbenes, carastilphenols A-E (1 – 5) and (–)-hopeachinol B (6), with three reported oligostilbenes were obtained from the stems of Caragana sinica. The structures of compounds 1 – 6 were determined by comprehensive spectroscopy analysis, and their absolute configurations were determined by electronic circular dichroism calculations. Thus, natural tetrastilbenes were determined as absolute configuration for the first time. Also, we did several pharmacological essays. In the antiviral tests, compounds 2 , 4 and 6 showed moderate anti-coxsackie virus B3 type (CVB3) effect on Vero cells activities in vitro with IC 50 values of 19.2 ∼ 69.3 μ M; and compounds 3 and 4 showed different levels of anti-respiratory syncytial virus (RSV) effect on Hep2 cells activities in vitro with IC 50 values of 23.1 and 33.3 μ M, respectively. As for hypoglycemic activity, compounds 6 – 9 (10 μ M) showed the inhibition of α -glucosidase in vitro with IC 50 values of 0.1 ∼ 0.4 μ M; and compound 7 showed significant inhibition (88.8%, 10 μ M) of protein tyrosine phosphatase 1B (PTP1B) with IC 50 value of 1.1 μ M in vitro. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nine undescribed monoterpene phenol dimers bisbakuchiols D-L (1 – 9) were isolated from the fruits of Psoralea corylifolia L. • A single crystal of compound 1 was obtained, and the absolute configurations of 1 was established by X-ray diffraction. • Compounds 5 and 9 exhibited significant PTP1B inhibitory activities with IC 50 values of 0.69 and 0.73 μ M. • A Molecular docking simulation of PTP1B and compounds 5 and 9 exhibited that these active compounds possess low binding affinities ranging from −6.9 to −7.1 kcal/mol. Nine undescribed monoterpene phenol dimers, bisbakuchiols D-L (1 – 9), were isolated from the fruits of Psoralea corylifolia L. Their structures were elucidated based on extensive spectral analysis. The absolute configurations of 1 – 9 were specified by experimental and quantum chemical calculations of ECD spectra, and that of 1 was further established by X-ray diffraction analysis using Cu Kα radiation. Bisbakuchiols (1 – 4) were composed of two bakuchiols, one of which was cyclized via a C-7′/ C-12′ single bond to form a six-member ring, and connect to each other by C–4–O–C–13 ' bonds. Bisbakuchiols (7 – 9) had a pyran ring by linkage of C–8–O–C–12. In the enzyme assay, compounds 5 and 9 exhibited significant PTP1B inhibitory activities with IC 50 values of 0.69 and 0.73 μ M, and compounds 1 and 3 showed moderate PTP1B inhibitory activities. Furthermore, a molecular docking simulation of PTP1B and active compounds 5 and 9 showed that these active compounds possess low binding affinities ranging from −6.9 to −7.1 kcal/mol. [ABSTRACT FROM AUTHOR]

Forest ecosystem conservation practice frequently sacrifices human livelihood, since there exists a structural conflict between both aspects in the degraded forest ecosystem. To reconcile the conflict has been widely viewed as a core issue, in which the payment of ecosystem service (PES) may play a critical role in solving this issue. In order to better understand the practical effectiveness of PES and explore the solution to reconcile the contradiction between conservation and livelihood, we investigated the decadal changes in the Sloping Land Conversion Program as a PES strategy in the Qilian Mountains, a degraded forest ecosystem of northwest China, and its effects on natural and social systems across the 10-year implementation period (2001–2011). The regional NDVI of study site was promoted from 46.24% to 61.28%, showing that vegetation cover had a massive increase during the whole implementation period. Also, the PES strategy had impelled more labor forces as migrant workers into the non-agricultural industries or urban areas. The migration dynamics in three industries demonstrated that the population of primary industry followed a gradually declining trend, and its percentage in total population was lowered from 33.44% to 19.82%. According to our household survey, local farmers reduced the economic investment in agriculture, and this enabled more labor forces to be released from agricultural industry. Interestingly, the attitudes towards the PES program for local inhabitants were gradually shifted from negative at initial stage to acceptable at middle stage, and finally to positive at late stage, as a consequence of PES application. In such case, the PES-led vegetation restoration strategy has been effectively implemented, which can reconcile the contradiction between conservation and livelihood, and ultimately achieve a win-win consequence. Our study provided a successful practical paradigm of coupled human and natural system (CHANS) in forest ecosystem restoration. • We analyzed the dilemma between forest conservation and human livelihood in China. • Sloping Land Conversion Program acted as the Payment for Ecosystem Service (PES). • The PES strategy accelerated the transfer of labors into non-agricultural industries. • Livelihood improvements promoted a fine shift of farmers' attitudes towards PES. • We established a CHANS model to highlight the role of PES in forest conservation. [ABSTRACT FROM AUTHOR]