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The Ganzi‐Yushu fault (GYF) is one of the most seismically active fault systems in eastern Tibet, having experienced five M > 7.0 earthquakes over the past 300 years. Here, we use Sentinel‐1 InSAR data spanning from 2014 to 2023 to derive the interseismic velocity fields along the GYF. We calculate the strain rate fields for the entire fault system, which reveal localized strain accumulation along the GYF as well as along two secondary faults within the Bayan Har block. The inversion results obtained from the elastic block model indicate left‐lateral strike slip rates of 4.0–6.5 mm/yr along the GYF and five locked segments distributed along strike. Furthermore, we identify two shallow creeping segments on the InSAR velocity maps. Based on the locations of the creeping sections and their temporal decay characteristics, we infer that the shallow creep along the GYF is afterslip of the 2010 Yushu earthquake. Plain Language Summary: The 500 km‐long Ganzi‐Yushu fault is a main fault system in eastern Tibet. Investigating its slip behavior is crucial for assessing earthquake potential and understanding the deformation patterns in the region. Using space geodetic observations, we investigate the slip rate distribution along the Ganzi‐Yushu fault. The energy accumulation along the fault can be divided into five segments, which correspond remarkably well with the historical events. Besides the Ganzi‐Yushu fault, we find that two secondary faults within the Bayan Har block, which had not received much attention before, also exhibit significant seismic hazard. We identify two shallow creeping sections along the fault. By analyzing the spatio‐temporal characteristics of the shallow creeping sections, we confirm that they are associated with postseismic activity of the 2010 Yushu earthquake. Our results give insights into the regional deformation mode and seismic hazard. Key Points: Our large‐scale high‐resolution InSAR velocity fields reveal strain accumulation within the Bayan Har blockThere are five locked segments distributed along the Ganzi‐Yushu fault, which corresponds well with historical eventsWe identify two transient shallow creeping segments associated with afterslip of the 2010 Yushu earthquake [ABSTRACT FROM AUTHOR]

GeTe has been considered as a promising mid‐temperature thermoelectric (TE) candidate, but its zT value is severely limited by the excessive hole concentration and high thermal conductivity. Here, it is demonstrated that the TE properties of GeTe can be significantly improve by defect engineering of Sb‐Pb and AgCuTe codoping. The Sb‐Pb codoping is adopted to optimize the carrier concentration and manipulate the rhombohedral lattice distortion, leading to valence band convergence and enhanced power factor. The AgCuTe alloying introduces multiscale phonon scattering centers including dislocations and nano‐precipitates to reduce the lattice thermal conductivity in GeTe. Consequently, a maximum zT of 2.3 at 773 K and an average zT of 1.43 (300–773 K) are obtained in (Ge0.84Sb0.06Pb0.1Te)0.99(AgCuTe)0.01. Moreover, the fabricated thermoelectric module exhibits a high output power density of 0.59 W cm–2 and an energy conversion efficiency of 7.9% at ΔT = 500 K, suggesting hierarchical defect engineering is an effective strategy to realize high‐performance GeTe‐based thermoelectric. [ABSTRACT FROM AUTHOR]

Antibiotic resistance has been threatening public health for a long period, while the COVID pandemic aggravated the scenario. To combat antibiotic resistance strains, host defense peptides (HDPs) mimicking molecules have attracted considerable attention. Herein, we reported a series of polycarbonates bearing cationic lysine amino acid residues that could mimic the mechanism of action of HDPs and possess broad‐spectrum antimicrobial activity. Moreover, those polymers had negligible toxicity toward red blood cells and mammalian cells. The membrane‐disruption mechanism endows the lysine‐containing polycarbonates with low possibility of resistance development and the fast killing kinetics, making them promising candidates for antimicrobial development. [ABSTRACT FROM AUTHOR]

The 2021 MW 7.4 Maduo event occurred within the Bayan Har block in eastern Tibet, which provides an opportunity to investigate the stress conditions and rheology of faults within the block. Here, we perform dynamic rupture simulations based on the finite element method to explore the physical conditions underlying this earthquake and the factors that controlled the rupture process. We construct the model with a nonplanar fault inferred from the Interferometric Synthetic Aperture Radar (InSAR) data and aftershocks sequence relocation. Our dynamic model is controlled by slip‐weakening friction law with initial stress on fault resolved from a uniform regional stress field. The preferred model produces an average slip of ∼2.2 m with a maximum slip of ∼4.0 m. There are three asperities distributed along the strike, which have captured the main features of the Maduo event. The simulation results are consistent with the static GPS coseismic surface displacements, InSAR data, and displacement waveforms recorded by high‐rate GNSS stations. By comparing the results with the planar fault model and rotated stress fields, we find that the fault geometry and regional stress field are the primary factors that control the rupture process of the event. Moreover, we infer that the unfavorable orientation and fault bend lead to minor slips on the branch fault. Furthermore, we investigate the potential mechanisms of supershear rupture on the eastern fault segment. Plain Language Summary: The 2021 Maduo event ruptured on an intra‐block fault of the Bayan Har block in the Tibetan Plateau, which has aroused widespread interest among the scientific community. In this study, we perform physics‐based numerical simulations based on a nonplanar fault to reproduce the source process of the event. The surface displacements obtained from our dynamic model are in good agreement with the observations. As the other parameters are relatively simple in our model, the source process of the event is mainly controlled by the geometric fault complexities. Our results also help to constrain the orientation of the regional stress field. We find that the branch fault of the earthquake is unfavorably oriented in the regional stress field as well as the fault bend also impedes the rupture to propagate on it, which leads to a minor slip on the branch fault. Furthermore, we infer that the supershear rupture may be induced by the free surface in the earthquake. Key Points: Our dynamic model reproduced the first‐order rupture characteristics of the Maduo earthquakeThe main factor that controls the multipeak slip pattern of the Maduo event is fault geometryThe orientation of the regional stress field was determined through numerical experiments [ABSTRACT FROM AUTHOR]

Bismuth telluride is the only commercially applied thermoelectric material. The n‐type material is usually prepared by the method of zone melting; however, the utilization ratio of the ingot is relatively low, owing to the bad thermoelectric performance of the two ends. Herein, the waste of n‐type bismuth telluride is recovered by the second zone melting and PbBr2 doping. It is shown that the second zone melting can improve the grain alignment, leading to the increase of carrier mobility. When PbBr2 doping is introduced, lattice thermal conductivity is largely reduced by the high dense dislocations. As a result, the peak power factor and maximum ZT reach 53 μW cm−1 K−2 and 1.15, respectively, which are even higher than the values of the original commercial material. This work provides an economic and applicable strategy to recover the waste of bismuth telluride thermoelectric materials. [ABSTRACT FROM AUTHOR]

Employees have their own understandings of corporate social responsibility (CSR) motives. This study investigated whether employees' different perceptions of CSR motives, including substantive CSR attribution and symbolic CSR attribution, influence their work attitudes, job satisfaction, and turnover intention. Moreover, we explore the mediating role of person‐organization fit in the relationships among CSR attribution, job satisfaction, and turnover intention. We collected 687 responses for an overall response rate of 16%. The results of structural equation model (SEM) analyses show that substantive CSR attribution decreases employee turnover intention and that symbolic CSR attribution increases employee turnover intention. Based on these results, we provide relevant theoretical and managerial implications. [ABSTRACT FROM AUTHOR]

This study examines the comparative effects of internal and external CSR perceptions on organizational citizenship behavior (OCB) and focuses on two consequences to compare CSR perception types. It also attempts to develop logical linkages between CSR perceptions and OCB through individual‐level psychological mechanisms, perceived external prestige, and affective commitment. The study is centered around the Chinese manufacturing and service industries using an online data‐collection platform similar to Qualtrics. The structural equation modeling technique was based on 200 supervisor/subordinate dyads. The quantitative analysis utilized SPSS and AMOS software. Results demonstrate that internal CSR perception has more benefits for OCB than external CSR perception. Since internal CSR inputs are often neglected by companies, results provide scholars and managers with a new view to pay attention to the potential of internal CSR inputs. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 is still wreaking havoc all over the world with surging morbidity and high mortality. The main protease (Mpro) is essential in the replication of SARS‐CoV‐2, enabling itself an active target for antiviral development. Herein, we reported the design and synthesis of a new class of peptidomimetics‐constrained α, γ‐AA peptides, based on which a series of aldehyde and ketoamide inhibitors of the Mpro of SARS‐CoV‐2 were prepared. The lead compounds showed excellent inhibitory activity in the FRET‐based Mpro enzymatic assay not only for the Mpro of SARS‐CoV‐2 but also for SARS‐CoV and MERS‐CoV, along with HCoVs like HCoV‐OC43, HCoV‐229E, HCoV‐NL63 and HKU1. The X‐ray crystallographic results demonstrated that our compounds form a covalent bond with the catalytic Cys145. They also demonstrated effective antiviral activity against live SARS‐CoV‐2. Overall, the results suggest that α, γ‐AA peptide could be a promising molecular scaffold in designing novel Mpro inhibitors of SARS‐CoV‐2 and other coronaviruses. [ABSTRACT FROM AUTHOR]

One of the most critical and yet unsolved issues is the effective monitoring of multiple heavy metal ions in complex systems through their specific function in fluorescence detection. In this work, luminescence‐active cadmium base metal‐organic frameworks (Cd‐MOFs) based on the planar and rigid π‐conjugated structure ligand benzo‐(1,2;3,4;5,6)‐tris (thiophene‐2'‐carboxylic acid) (H3BTTC) was chosen. A series of sensing experiments demonstrated that the Cd‐MOFs exhibits selective and sensitive response for Fe3+ and Eu3+ through fluorescence "turn off" and "antenna effect" respectively. In addition, the encapsulation of Eu3+ inside the Cd‐MOFs (Eu3+@Cd‐MOFs) led to an excellent probe with dual emission. To this end, a programmable fluorescence platform was developed to detect Fe3+ and Cu2+, in which the emission peaks of both the ligand and Eu3+ are completely quenched by Fe3+. The ratiometric detection of Cu2+ leads to a decrease in Eu3+ emission, while the ligand emission remains stable. To demonstrate the strategy, the fluorescence (Output) of Cd‐MOFs, Eu3+@Cd‐MOFs, and the analytes (Eu3+, Fe3+, and Cu2+, input) achieved elementary Boolean logic operations (OR, NOR, AND) and they constitute a logic fluorescent chemosensor to analyze Fe3+ and Cu2+ synchronously. [ABSTRACT FROM AUTHOR]

PbSe has been expected to be a competitor of the excellent thermoelectric material PbTe, whereas its performance has proved to be limited by its intrinsic electronic structure. In this work, the improved thermoelectric performance of PbSe originating in the novel spin‐orbit coupling effect is reported. By alloying with NaSbSe2, valence band convergence and bandgap enlargement are achieved in PbSe, resulting in a significantly enlarged Seebeck coefficient. Theoretical calculations indicate that a modified electronic structure by spin‐orbit coupling would lead to exotic thermoelectric properties and that it prefers a lower carrier concentration than the known optimal value for PbSe. When Cd‐doping is introduced to decrease the carrier concentration, a high peak ZT of 1.6 at 850 K and a remarkable average ZT of 0.95 are obtained in Pb0.8Na0.1Sb0.08Cd0.02Se. Among the reported high ZT PbSe‐based compounds, the sample exhibits the highest Seebeck coefficient and lowest thermal conductivity. This study provides an insight into band structure tuning of Lead chalcogenides and promotes a new strategy for the optimization of thermoelectric performance. [ABSTRACT FROM AUTHOR]

Through continuous efforts in developing a new class of foldamers, homogeneous sulfono‐γ‐AApeptides have been designed and synthesized using tetraphenylethylene (TPE) moieties attached to the backbone as luminogenic sidechains. Based on previous crystal structures, it is found that these foldamers adopted a left‐handed 414‐helix. Due to the constraint of the helical scaffold, the rotation of the TPE moieties is restricted, leading to fluorescent emissive properties with high quantum yields not only at the aggregate state but also in solution. Investigation of the relationship between the structure and fluorescence behavior reveals that emission is induced by the combined effect of the aggregation‐induced emission and the rotated restriction from the backbone. Furthermore, as the packing mode of the luminogens can be precisely adjusted by the helical backbone, these foldamers are found to be circularly polarizable with relatively large luminescence dissymmetry factor. Interestingly, possessing cationic amphipathic structures similar to that of host‐defense peptides, these sulfono‐γ‐AApeptides are able to inhibit the growth of Gram‐positive bacteria, methicillin‐resistant Staphylococcus aureus through membrane interactions. [ABSTRACT FROM AUTHOR]

Herein, the enantiomeric separation of simendan by high‐performance liquid chromatography with ultraviolet detection using polysaccharide‐based chiral stationary phases in polar organic mode is described. Three chiral columns (Chiralpak AD‐H, Chiralcel OD‐H, and Chiralpak AS) were screened using pure methanol and acetonitrile without additives under isocratic conditions. A reversed elution order was observed on the Chiralpak AD‐H column when the methanol content in the mobile phase (methanol–acetonitrile mixtures) was above 10%, whereby levosimendan eluted prior to dextrosimendan. Further, it was found that increasing temperature effectively improved the enantioresolution on the Chiralpak AD‐H column. Van't Hoff analysis was performed to evaluate the contribution of enthalpy and entropy to the chiral discrimination process. The best enantioseparation (α = 3.00, Rs = 12.85) was obtained on the Chiralpak AD‐H column with methanol as the mobile phase at 40°C. Thus, a quantitative method for the resolution of dextrosimendan was established and validated, which could be used as a reference for the determination of dextrosimendan in levosimendan products. [ABSTRACT FROM AUTHOR]

Metal‐organic framework (MOF) compounds ZIF‐8 and Uio‐66 were synthesized by the solvent‐thermal method; then loaded with silver nanoparticles and studied to determine their adsorption of formaldehyde gas. The results showed that when the loading of silver nanoparticles was 2.5 wt%, Ag NPs@ZIF‐8 had the highest adsorption rate for formaldehyde gas, with the adsorption capacity 8.2‐11.5 times greater than that of ZIF‐8. When the loading of silver nanoparticle was 5 wt%, the adsorption capacity of Ag NPs@Uio‐66 for formaldehyde gas was 1.75 times higher than that of Uio‐66. [ABSTRACT FROM AUTHOR]

A new photoresponsive bis (crown ether) 1 was synthesized from carboxylic crown ethers and 4,4′ ‐ hydroxy azobenzene, and its ability for the extraction of alkali metal, alkaline earth metal, and partial transition metal ions was also studied. Intriguingly, our results showed that the extraction rate of metal ions by compound 1 after light irradiation was generally more efficient than in the ambient light. Particularly, compound 1 displayed excellent selectivity for Sr2+ under UV light irradiation, as a result of the formation of a sandwich complex with metal ions, suggesting its promising potential application to selectively extract strontium ions. [ABSTRACT FROM AUTHOR]

The low cytotoxic Zr‐based MOF PCN‐221, which exhibited the ability to entrap β‐estradiol model drug, was studied as a drug delivery system. As a comparison, another drug carrier, halloysite nanotubes, was also investigated. Both PCN‐221 and halloysite nanotubes were characterized by IR spectroscopy, powder X‐ray diffraction (PXRD), and transmission electron microscopy (TEM). β‐estradiol was loaded mainly on skeleton and partially on the external surface of PCN‐221. We show that controlled release of β‐estradiol from PCN‐221 was observed over more than 31 days, compared with the 20 days release period from halloysite nanotubes, indicating PCN‐221 are a superior carriers of β‐estradiol. [ABSTRACT FROM AUTHOR]

6‐(4‐Aminophenyl)‐5‐methyl‐4,5‐dihydro‐3(2H)‐pyridazinone is a key synthetic intermediate for cardiotonic agent levosimendan. Very few studies address the use of chiral stationary phases in chromatography for the enantioseparation of this intermediate. This study presents two efficient preparative methods for the isolation of (R)(−)‐6‐(4‐aminophenyl)‐5‐methyl‐4,5‐dihydro‐3(2H)‐pyridazinone in polar organic solvent chromatography and supercritical fluid chromatography using polysaccharide‐based chiral stationary phases and volatile organic mobile phases without additives in isocratic mode. Under optimum conditions, Chiralcel OJ column showed the best performance (α = 1.71, Rs = 5.47) in polar organic solvent chromatography, while Chiralpak AS column exhibited remarkable separations (α = 1.81 and Rs = 6.51) in supercritical fluid chromatography with an opposite enantiomer elution order. Considering the sample solubility, runtime and solvent cost, the preparations were carried out on Chiralcel OJ column and Chiralpak AS column (250 × 20 mm i.d.; 10 µm) in polar organic mode and supercritical fluid chromatography mode with methanol and CO2/methanol as mobile phases, respectively. By utilizing the advantages of chromatographic techniques and polysaccharide‐based chiral stationary phases, this work provides two methods for the fast and economic preparation of (R)(−)‐6‐(4‐aminophenyl)‐5‐methyl‐4,5‐dihydro‐3(2H)‐pyridazinone, which are suitable for the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Peptide‐mediated self‐assembly is a prevalent method for creating highly ordered supramolecular architectures. Herein, we report the first example of orthogonal C−X⋅⋅⋅X−C/C−X⋅⋅⋅π halogen bonding and hydrogen bonding driven crystalline architectures based on synthetic helical peptides bearing hybrids of l‐sulfono‐γ‐AApeptides and natural amino acids. The combination of halogen bonding, intra‐/intermolecular hydrogen bonding, and intermolecular hydrophobic interactions enabled novel 3D supramolecular assembly. The orthogonal halogen bonding in the supramolecular architecture exerts a novel mechanism for the self‐assembly of synthetic peptide foldamers and gives new insights into molecular recognition, supramolecular design, and rational design of biomimetic structures. [ABSTRACT FROM AUTHOR]

Abstract: The development of peptidomimetic helical foldamers with a wide repertoire of functions is of significant interest. Herein, we report the X‐ray crystal structures of a series of homogeneous l‐sulfono‐γ‐AA foldamers and elucidate their folding conformation at the atomic level. Single‐crystal X‐ray crystallography revealed that this class of oligomers fold into unprecedented dragon‐boat‐shaped and unexpected left‐handed helices, which are stabilized by the 14‐hydrogen‐bonding pattern present in all sequences. These l‐sulfono‐γ‐AApeptides have a helical pitch of 5.1 Å and exactly four side chains per turn, and the side chains lie perfectly on top of each other along the helical axis. 2D NMR spectroscopy, computational simulations, and CD studies support the folding conformation in solution. Our results provide a structural basis at the atomic level for the design of novel biomimetics with a precise arrangement of functional groups in three dimensions. [ABSTRACT FROM AUTHOR]

As a common traditional Chinese medicine, Fructus Arctii has important clinical medical values. Its main components are lignans, which are difficult to separate and analyze because of the complex composition, similar chemical structures, and close properties. In this study, an off-line two-dimensional supercritical fluid chromatography/reversed-phase liquid chromatography method, as well as an effective sample pretreatment method based on hydrophilic interaction chromatography material, was developed to enrich the minor lignan fractions and obtain high-purity compounds. In total, 12 high-purity compounds were isolated from Fructus Arctii. Their structures were identified by using high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy, which showed that all were lignans and that most of them were isomers. The results demonstrated the effective off-line twodimensional supercritical fluid chromatography/reversed-phase liquid chromatography method for the purification of lignans from Fructus Arctii. The separation protocol established here will be beneficial for the separation of complex samples from other kinds of natural products. [ABSTRACT FROM AUTHOR]

An orthogonal (71.9%) off-line preparative two-dimensional normal-phase liquid chromatography/reversed-phase liquid chromatography method coupled with effective sample pretreatment was developed for separation and purification of flavonoids from licorice. Most of the nonflavonoids were firstly removed using a self-made Click TE-Cys (60 μm) solid-phase extraction. In the first dimension, an industrial grade preparative chromatography was employed to purify the crude flavonoids. Click TE-Cys (10 μm) was selected as the stationary phase that provided an excellent separation with high reproducibility. Ethyl acetate/ethanol was selected as the mobile phase owing to their excellent solubility for flavonoids. Flavonoids co-eluted in the first dimension were selected for further purification using reversed-phase liquid chromatography. Multiple compounds could be isolated from one normal-phase fraction and some compounds with bad resolution in one-dimensional liquid chromatography could be prepared in this two-dimensional system owing to the orthogonal separation. Moreover, this two-dimensional liquid chromatography method was beneficial for the preparation of relatively trace flavonoid compounds, which were enriched in the first dimension and further purified in the second dimension. Totally, 24 flavonoid compounds with high purity were obtained. The results demonstrated that the off-line two-dimensional liquid chromatography method was effective for the preparative separation and purification of flavonoids from licorice. [ABSTRACT FROM AUTHOR]

In this study, two mixed-mode chromatography stationary phases (C8SAX and C8SCX) were evaluated and used to establish a two-dimensional liquid chromatography system for the separation of traditional Chinese medicine. The chromatographic properties of the mixed-mode columns were systematically evaluated by comparing with other three columns of C8, strong anion exchanger, and strong cation exchanger. The result showed that C8SAX and C8SCX had a mixed-mode retention mechanism including electrostatic interaction and hydrophobic interaction. Especially, they were suitable for separating acidic and/or basic compounds and their separation selectivities could be easily adjusted by changing pH value. Then, several off-line 2D-LC systems based on the C8SAX in the first dimension and C8SAX, C8SCX, or C8 columns in the second dimension were developed to analyze a traditional Chinese medicine- Uncaria rhynchophylla. The two-dimensional liquid chromatography system of C8SAX (pH 3.0) × C8SAX (pH 6.0) exhibited the most effective peak distribution. Finally, fractions of U. rhynchophylla prepared from the first dimension were successfully separated on the C8SAX column with a gradient pH. Thus, the mixed-mode stationary phase could provide a platform to separate the traditional Chinese medicine in practical applications. [ABSTRACT FROM AUTHOR]

Sequence-specific peptidomimetics are molecules that mimic the structure and function of peptides and proteins. With new backbones and molecular frameworks, peptidomimetics are of considerable interest in addressing challenges encountered in chemical biology and biomedical sciences. Based on the γ-PNA backbone, a new class of peptidomimetics - 'γ-AApeptides' were recently developed. Both linear and cyclic γ-AApeptides can be synthesized with high efficiency. Compared with α-peptides, γ-AApeptides are resistant to enzymatic degradation, and amendable to diversification with a variety of chemical groups. Moreover, they could mimic primary and secondary structure, as well as the function of peptides, and show promise in biological applications, such as the development of new agents combating bacteria, cancer, and Alzheimer's disease. A few research outcomes of γ-AApeptides are highlighted in this Concept article, and a future perspective is also proposed. [ABSTRACT FROM AUTHOR]

A bispyrene fluorescence probe with the cavitand linkage (compound 1) was synthesized, which was proved to be a versatile platform due to the ability of adopting two spatially well‐defined conformations: a closed vase and an expanded kite. vase‐1 was switched to kite‐1 upon addition of TFA or cooling, whereas kite‐1 was isomerized to vase‐1 in the presence of NEt3 or through heating. The interconversion in this molecular switch was tightly associated with the change of fluorescence as we found that changing the temperature and pH of the system‐ a bispyrene compound 1 and gelator 2 led to the sol ‐ gel transformation and reversible intramolecular excimer emission. Briefly, the results show that the fluorescence decreases in the gelation phase and is enhanced in the solution due to variations in temperature and pH. we thus concluded that 1 could be a useful fluorescence probe to determine the multiple states of organogel. [ABSTRACT FROM AUTHOR]

Continuous and intergrown metal-organic framework (MOF) membranes, MIL-100(In) (MIL represents Materials Institute Lavoisier), were prepared directly on porous anodic alumina oxide (AAO) membranes using an in situ crystallization method. The pore surface of MIL-100(In) is conferred with polarity due to the presence of the 1, 3,5-benzenetricarboxylic acid. The thickness of MIL-100(In) membranes was tuned by varying the reactant concentration of indium chloride and 1, 3,5-benzenetricarboxylic acid. Single gas permeation measurements on this MOF membrane indicate the large permeances of 0.90 × 10-6 and 0.81 × 10-6 mol ·m-2·s-1·Pa-1 for CO2 and CH4, and relatively high ideal selective factors of 3.75 and 3.38 for CO2/N2 and CH4/N2, respectively. [ABSTRACT FROM AUTHOR]

Foldamers offer an attractive opportunity for the design of novel molecules that mimic the structures and functions of proteins and enzymes including biocatalysis and biomolecular recognition. Herein we report a new class of nonnatural helical sulfono-γ-AApeptide foldamers of varying lengths. The crystal structure of the sulfono-γ-AApeptide monomer S6 illustrates the intrinsic folding propensity of sulfono-γ-AApeptides, which likely originates from the bulkiness of tertiary sulfonamide moiety. The two-dimensional solution NMR spectroscopy data for the longest sequence S1 demonstrates a 10/16 right-handed helical structure. Optical analysis using circular dichroism further supports well- defined helical conformation of sulfono-γ-AApeptides in solution containing as few as five building blocks. Future development of sulfono-γ-AApeptides may lead to new foldamers with discrete functions, enabling expanded application in chemical biology and biomedical sciences. [ABSTRACT FROM AUTHOR]

The C9-position of quinine was modified by meta- or para-substituted benzo-18-crown-6, and immobilized on 3-mercaptopropyl-modified silica gel through the radical thiol-ene addition reaction. These two chiral stationary phases were evaluated by chiral acids, amino acids, and chiral primary amines. The crown ether moiety on the quinine anion exchanger provided a ligand-exchange site for primary amino groups, which played an important role in the retention and enantioselectivity for chiral compounds containing primary amine groups. These two stationary phases showed good selectivity for some amino acids. The complex interaction between crown ether and protonated primary amino group was investigated by the addition of inorganic salts such as LiCl, NH4Cl, NaCl, and KCl to the mobile phase. The resolution results showed that the simultaneous interactions between two function moieties (quinine and crown ether) and amino acids were important for the chiral separation. [ABSTRACT FROM AUTHOR]

Linguistic fuzzy preference relations are commonly used in decision-making problems. The recent proposal of comparative linguistic expressions has been introduced to deal with the situation that decision makers hesitate among several linguistic terms to express their assessments. To apply this idea to linguistic fuzzy preference relations, we propose the linguistic fuzzy preference relations based on the comparative linguistic expressions. We then transform the linguistic fuzzy preference relations into linguistic 2-tuple fuzzy preference relations, and introduce an iterative method to measure and improve the additive consistency of the linguistic 2-tuple fuzzy preference relations. An illustrative example is finally presented to clarify the computational processes. [ABSTRACT FROM AUTHOR]

Herein we report a highly efficient new method for preparing γ-AApeptides capable of theoretically containing any functionality; the method uses a few common N-alloc γ-AApeptide building blocks. More importantly, using the same approach, new classes of peptidomimetics bearing novel backbone scaffolds can also be readily generated. Our results not only demonstrate the versatility of this new synthetic method, but also highlight the possibility that the resulting novel peptidomimetics may find discrete biomedical/biomaterial applications in the future. [ABSTRACT FROM AUTHOR]

Crystal engineering of the nbo metal-organic framework (MOF) platform MOF-505 with a custom-designed azamacrocycle ligand (1,4,7,10-tetrazazcyclododecane- N, N′, N′′, N′′′-tetra- p-methylbenzoic acid) leads to a high density of well-oriented Lewis active sites within the cuboctahedral cage in MMCF-2, [Cu2(Cu-tactmb)(H2O)3(NO3)2]. This MOF demonstrates high catalytic activity for the chemical fixation of CO2 into cyclic carbonates at room temperature under 1 atm pressure. [ABSTRACT FROM AUTHOR]

Norcantharidin ( NCTD), the demethylated form of Cantharidin, a reagent isolated from blister beetles, has been shown to be an anti-tumor agent capable of inhibiting proliferation as well as inducing apoptosis in many cancer cell lines. However, little is known about the effect of NCTD in tumor angiogenesis. In this study, we demonstrated that NCTD inhibited vascular endothelial growth factor ( VEGF)-induced cell proliferation, migration, invasion, and capillary tube formation of primary human umbilical vein endothelial cells ( HUVECs) in a dose-dependent manner. Furthermore, we showed NCTD inhibited tumor growth and angiogenesis of colon cancer cells ( LOVO) in vivo. We then mechanistically described that NCTD specifically abrogated the phosphorylation/activation of vascular endothelial growth factor receptor-2 ( VEGFR2)/ MEK/ ERK pathway kinases, with little effect on the phosphorylation of p38 MAPK and Akt, and on Cox-2 expression. In summary, our results indicate that NCTD is a potential inhibitor of tumor angiogenesis by blocking VEGFR2/ MEK/ ERK signaling. [ABSTRACT FROM AUTHOR]

In this paper, VHESH, which was a novel set of amino acid descriptors including hydrophobic, electronic, steric, and hydrogen bond contribution properties, were proposed to characterize the structures of the decapeptides binding the human amphiphysin-1 Src homology 3 (SH3) domains, and QSAR model was constructed by partial least square (PLS) with genetic algorithm-variable selection. It was found that diversified properties of the residues between P2 and P−3 (including P2 and P−3) of the decapeptide (P4P3P2P1P0P−1P−2P−3P−4P−5) may contribute remarkable effect to the interactions between the SH3 domain and decapeptides. Particularly, hydrogen bond and steric properties of P2 and electronic properties, steric properties of P−3 may provide relatively large positive contributions to the interactions. Based on the GA-PLS model, a series of decapeptides, with relatively high binding affinities were designed. These results showed that VHESH descriptors can well represent the decapeptides. Furthermore, the model obtained, which showed low computational complexity, correlated VHESH descriptors with the binding affinities as well as that VHESH may also be applied in QSAR studies of peptides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Due to the high intrinsic zT of≈1.0 by multi‐band valleys, GeTe‐based thermoelectric materials are promising for medium‐temperature applications. In this work, the extraordinary role of the new dopant Hg on the electro‐phonon transport of GeTe is comprehensively elucidated. According to the first‐principles calculations, Hg doping can effectively reduce the energy offset between light and heavy valence bands, and increase the density‐of‐states effective mass md∗$m_d^*$ from 1.45 m0 to 2.58 m0. Experimentally, the (GeTe)1‐x(HgTe)x samples are demonstrated to possess an enhanced room‐temperature Seebeck coefficient from 30.3 to 59.9 µV K−1, plus an outstanding average power factor (300–773 K) of 28.8 µW cm−1 K−2. The Pb‐Bi codoping further optimizes the hole concentration and significantly suppresses the lattice thermal conductivity to 0.47 W m−1 K−1 by the induced various phonon scattering centers including dense point defects, grain boundaries, dislocations, and nano‐precipitates. Consequently, a high zTmax of 2.31 at 650 K and an average zTavg of 1.52 between 300 and 773 K are obtained in (Ge0.89Pb0.08Bi0.03Te)0.97(HgTe)0.03. Utilizing the optimized materials, achieving a high energy conversion efficiency of 10.8% at a temperature difference of 500 K in the fabricated 7‐pair thermoelectric module. This study clarifies the multiple benefits of Hg doping in GeTe‐based derivatives and provides a framework for designing high‐performance medium‐temperature thermoelectric materials. [ABSTRACT FROM AUTHOR]