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The surge in urbanization has correspondingly given rise to exacerbated carbon footprint and burgeoning heavy metal (HM) contamination, constituting a critical impediment to the realization of environmentally sustainable urban development pathways. Therefore, it is highly essential to investigate the impacts of urbanization process on soil carbon, heavy metals (HMs), as well as their interrelationships. Employing remote sensing and land use data within a 45 km radius in Chongqing, this study selected 31 sites to assess the variation in urban green spaces (UGSs) carbon sequestration capabilities and associated HM pollution risks across differing urbanization levels. Results showed that urbanization dynamics and land use history play a more decisive role than current anthropogenic management in shaping the distribution of soil carbon and HMs within urban environments. The average soil organic carbon (SOC) distribution of UGSs is 8.47 mg ha−1 (1.50–24.20 mg ha−1), concurrent with moderate HM pollution showing Ni: 32.03–33.50 mg kg−1, Pb: 27.93–29.65 mg kg−1, Cu: 26.97–41.20 mg kg−1, while Cd exhibits the most severe pollution range of 0.23–0.30 mg kg−1. The rate of urbanization significantly influences SOC stocks, exhibiting an increase when the urbanization rate is below 70.79 % and a decrease upon surpassing this threshold. The concentration of HMs is predominantly determined by the historical usage of the land, with a marked escalation correlating with the duration of land utilization history. These relationships were quantitatively modeled through the application of fitted linear functions. The structural equation model demonstrated that UGSs operating without anthropogenic disturbance tend towards degradation, indicating that temporary homeostasis might be sustained via the addition of N and P nutrients and pH modulation. In conclusion, we formulate an Urban Green Spaces Development Hypothesis that aims to shed light on the multifaceted challenges encountered by cities amidst varying degrees of urbanization and, concurrently, to probe potential ameliorative strategies.

Abstract The relaxation time under zero field reflects the memory retention capabilities of single‐molecule magnets (SMMs) when used as storage devices. Intermolecular magnetic dipole interaction is ubiquitous in aggregates of magnetic molecules and can greatly influence relaxation times. However, such interaction is often considered harmful and challenging to manipulate in molecular solids, especially for high‐performance lanthanide single‐ion magnets (SIMs). By an elaborately designed combination of ion pairing and hydrogen bonding, we have synthesized two pseudo‐D5h SIMs with supramolecular arrangements of magnetic dipoles in staggered and side‐by‐side patterns, the latter of which exhibits a 104‐fold slower zero‐field relaxation time at 2 K. Intriguingly, the side‐by‐side complex exhibits a significantly accelerated magnetic relaxation upon diamagnetic dilution, contrary to the general trend observed in the staggered complex. This strongly reveals the presence of aggregation‐induced suppression of quantum tunneling in a side‐by‐side arrangement, which has not been observed in mononuclear SMMs. By leveraging ion‐pairing aggregation and converting to a side‐by‐side pattern, this study successfully demonstrates an approach to transform a harmful intermolecular dipole interaction into a beneficial one, achieving a τQTM of 980 s ranking among the best‐performance SMMs.

This study explored a new model of Prostate Imaging Reporting and Data System (PIRADS) and adjusted prostate-specific antigen density of peripheral zone (aPSADPZ) for predicting the occurrence of prostate cancer (PCa) and clinically significant prostate cancer (csPCa). The demographic and clinical characteristics of 853 patients were recorded. Prostate-specific antigen (PSA), PSA density (PSAD), PSAD of peripheral zone (PSADPZ), aPSADPZ, and peripheral zone volume ratio (PZ-ratio) were calculated and subjected to receiver operating characteristic (ROC) curve analysis. The calibration and discrimination abilities of new nomograms were verified with the calibration curve and area under the ROC curve (AUC). The clinical benefits of these models were evaluated by decision curve analysis and clinical impact curves. The AUCs of PSA, PSAD, PSADPZ, aPSADPZ, and PZ-ratio were 0.669, 0.762, 0.659, 0.812, and 0.748 for PCa diagnosis, while 0.713, 0.788, 0.694, 0.828, and 0.735 for csPCa diagnosis, respectively. All nomograms displayed higher net benefit and better overall calibration than the scenarios for predicting the occurrence of PCa or csPCa. The new model significantly improved the diagnostic accuracy of PCa (0.945 vs 0.830, P < 0.01) and csPCa (0.937 vs 0.845, P < 0.01) compared with the base model. In addition, the number of patients with PCa and csPCa predicted by the new model was in good agreement with the actual number of patients with PCa and csPCa in high-risk threshold. This study demonstrates that aPSADPZ has a higher predictive accuracy for PCa diagnosis than the conventional indicators. Combining aPSADPZ with PIRADS can improve PCa diagnosis and avoid unnecessary biopsies.

An acetate bridged tetranuclear copper(II) complex, [Cu4L2(μ2-η1:η1-CH3COO)6(CH3OH)2] (1), and a chloride, phenolate and azide co-bridged tetranuclear copper(II) complex, [Cu4L2Cl2(μ-Cl)2(μ1,1-N3)2]2CH3OH (2), where L is the deprotonated form of the Schiff base 5-bromo-2-((2-(2-hydroxyethylamino)ethylimino)methyl)phenol (HL), have been synthesized and characterized by elemental analysis, IR and UV spectra, and single crystal X-ray diffraction. Single crystal X-ray analysis revealed that the Cu atoms in both complexes are in square pyramidal geometry. In complex 1, two [CuL] units and [Cu2(μ2-η1:η1-CH3COO)4] core are linked through two acetate ligands. In complex 2, [Cu2LCl(μ-Cl)] units are linked together by two end-on azido ligands. The Schiff base ligand coordinates to the Cu atoms through four N and O donor atoms. The molecules of both complexes are linked through hydrogen bonds to generate three dimensional networks. The catalytic property of the complexes for epoxidation reactions of some alkenes was studied using tert-butylhydroperoxide as the terminal oxidant under mild conditions in acetonitrile.

The first complete mitochondrial genome of Lixus subtilis Boheman is reported in this study. The circular genome is 15,223 bp long, including a standard set of 21 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), 13 protein-coding genes, and a non-coding control region. The trnI gene was not found in the L. subtilis mitogenome. All tRNAs had the typical cloverleaf structure, except for trnS1, which lacked the dihydrouridine arm. The phylogenetic tree of 13 Curculionidae species based on the concatenated nucleotide sequences of complete mitochondrial genomes strongly supported that L. subtilis is closely related to Curculioninae and Molytinae.

Given the limitations of existing therapeutic agents for treatment of postmenopausal osteoporosis, there still remains a need for more options with both efficacy and less adverse effects. Cistanche deserticola Y. C. Ma is known as a popular tonic herb traditionally used to treatment deficiency of kidney energy including muscle weakness in minority area of Asian counties. Based on the theory of “kidney dominate bone,” an ovariectomized (OVX) rat model of postmenopausal osteoporosis was used to evaluate the therapeutic effect of C. deserticola extract (CDE) on bone loss. Forty eight female Sprague-Dawley rats, aged about 12 weeks, were randomly assigned into six groups including sham group orally administrated with 0.5% carboxymethyl cellulose sodium (CMC-Na) (sham), positive group treated with 1 mg/kg of estradiol valerate (EV), low, moderate, and high dosage groups orally administrated with 200, 400, and 800 mg/kg/day of CDE, respectively. After 3 months of continuous intervention, CDE exhibited significant anti-osteoporotic activity evidenced by the enhanced total bone mineral density, ameliorated bone microarchitecture; increased alkaline phosphatase activity; decreased deoxypyridinoline, cathepsin K, tartrate-resistant acid phosphatase, and malondialdehyde levels; whereas the body, uterus, and vagina weights in OVX rats were not influenced by CDE intervention. In addition, a seemed contradictory phenomenon on levels of calcium and phosphorus between OVX and sham rats were observed and elucidated. Mechanistically, CDE significantly down-regulated the levels of TRAF6, RANKL, RANK, NF-κB, IKKβ, NFAT2, and up-regulated the phosphatidylinositol 3-kinase (PI3K), AKT, osteoprotegerin, and c-Fos expressions, which implied CDE could suppress RANKL/RANK-induced activation of downstream NF-κB and PI3K/AKT pathways, and ultimately, preventing activity of the key osteoclastogenic proteins NFAT2 and c-Fos. All of the data suggested CDE possessed potential anti-osteoporotic activity and this effect was, at least in part, involved in modulation of RANKL/RANK/TRAF6-mediated NF-κB and PI3K/AKT signaling as well as c-Fos and NFAT2 levels. Therefore, CDE may represent a useful promising remedy candidate for treatment of postmenopausal osteoporosis.

In the title mononuclear complex, [Zn(C7H4NO4)2(C8H8N2S)2], the ZnII atom is coordinated by two N atoms from two 2-amino-6-methyl-1,3-benzothiazole and by two carboxylate O atoms from two 4-nitrobenzoate ligands, adopting a slightly distorted tetrahedral coordination geometry. In the crystal, intermolecular N—H...O hydrogen bonds between the amino group of 2-amino-6-methyl-1,3-benzothiazole and the carboxylate group of 4-nitrobenzoate link these discrete mononuclear units into a one-dimensional supramolecular chain extending parallel to [100].

The crystal structure of the title complex, [Zn(C7H6NO2S)2(H2O)]n, consists of extended layers parallel to (001) with 2-(pyridin-4-ylsulfanyl)acetate ligands bridging the ZnII atoms. The ZnII atom shows a distorted pentagonal–bipyramidal coordination environment. The ZnII and one O atom are situated on a crystallographic twofold rotation axis. In the crystal, intralayer O—H...O hydrogen-bond interactions help to consolidate the coordination layer.

In the centrosymmetric title complex, [Ni(C7H6NO2S)2(H2O)4], the NiII atom, located on a centre of inversion, is coordinated by two N atoms from two 2-(4-pyridylsulfanyl)acetate ligands and four water O atoms in an octahedral geometry. In the crystal, intermolecular O—H...O hydrogen bonds between the coordinated water molecules and the carboxylate group of the anionic 2-(4-pyridylsulfanyl)acetate ligands link these discrete mononuclear units into a three-dimensional network.

The title compound, C12H8N2O4, crystallizes as a zwitterion in which the pyridyl N atom is protonated. The dihedral angle between the benzene and pyridinium rings is 27.9 (2)°. In the crystal, N—H...O hydrogen bonds link adjacent zwitterions into a three-dimensional structure.

In the crystal structure of the title compound, [Zn(C8H9N2O4)2(H2O)2]·2C3H7NO, the ZnII atom is coordinated by two N,O-bidentate 2-propyl-1H-imidazole-4,5-dicarboxylate anions and two water molecules in a distorted octahedral environment. The asymmetric unit consists of one ZnII atom located on a center of inversion as well as one anion, one water molecule and one additional dimethylformamide molecule that occupy general positions. Between the carboxyl and the carboxylate group an intramolecular hydrogen bond is found in which the hydroxy H atom is disordered. Disorder is also found for the H atoms of one of the three methyl groups. In the crystal structure, additional intermolecular N—H...O and O—H...O hydrogen bonding is found.

The title CuII coordination polymer, {[Cu(C7H10N6)2(H2O)2](NO3)2·H2O}n, was obtained by the reaction of equimolar Cu(NO3)2·4H2O and 1,3-bis(1,2,4-triazol-1-yl)propane (btp) in a water–methanol solvent. The CuII atom is located on a centre of inversion and has an elongated octahedral coordination geometry formed by four N atoms from four symmetry-related btp ligands and two coordinated water molecules. Adjacent CuII atoms are connected by btp ligands, generating a double-stranded chain. The nitrate anion is disordered over two positions in a 0.828 (7):0.172 (2) ratio.

Co-crystallization of 2-amino-6-methyl-1,3-benzothiazole with decanedioic acid under hydrothermal conditions afforded the title 2:1 co-crystal, 2C8H8N2S·C10H18O4. The decanedioic acid molecule is located on an inversion centre. In the crystal, intermolecular N—H...O and O—H...O hydrogen bonds connect the components into a two-dimensional wave-like layer structure extending parallel to (100).

In the mixed ligand title compound, [Cd(C6H11NO2)(C7H4NO4)2(H2O)], which exhibits a discrete mononuclear structure, the CdII atom is in a distorted octahedral geometry, surrounded by five carboxylate O atoms and one coordinated water molecule. The piperdinium ring adopts a chair conformation and the two 4-nitrobenzoate rings are oriented at a dihedral angle of 75.8 (1)°. Intermolecular O—H...O and N—H...O hydrogen bonds link the mononuclear entities into a three-dimensional supramolecular network.

Cocrystallization of 2-aminobenzothiazole with benzene-1,2,4-tricarboxylic acid in a mixed solvent affords the title ternary cocrystal, C7H7N2S+·C9H5O6−·H2O, in which one of the carboxyl groups of the benzenetricarboxylic acid is deprotonated and the heterocyclic N atom of the 2-aminobenzothiazole is protonated. In the crystal, intermolecular N—H...O and O—H...O hydrogen-bonding interactions stabilize the packing.

In the title compound, [Cu(C17H15NO3)(C3H4N2)], the CuII atom is four-coordinated by two O atoms and the N atom of the tridentate Schiff base ligand, and one N atom from the imidazole ligand in a distorted square-planar geometry. In the crystal structure, molecules are linked into dimers by intermolecular N—H...O hydrogen bonds.

Four new fluoro-containing hydrazones were synthesized from 4-fluorobenzaldehyde with chloro- and nitro-substituted benzohydrazides. They are 3-chloro-N'-(4-fluorobenzylidene)benzohydrazide (1), 2-chloro-N'-(4-fluorobenzylidene) benzohydrazide (2), N'-(4-fluorobenzylidene)-4-nitrobenzohydrazide (3), and N'-(4-fluorobenzylidene)-3-nitrobenzohydrazide (4). The compounds have been characterized by IR and 1H NMR spectroscopy, as well as X-ray single crystal determination. Xanthine oxidase (XO) inhibitory activity indicated that the nitro substituted compounds 3 and 4 have effective activity. Docking simulation was performed to insert the compounds into the crystal structure of xanthine oxidase at the active site to investigate the probable binding modes. [ABSTRACT FROM AUTHOR]

Herein, a copper(I)‐catalyzed asymmetric hydrophosphination of 3,3‐disubstituted cyclopropenes is reported. It provides a series of phosphine derivatives in high to excellent diastereo‐ and enantioselectivities. The methodology enjoys broad substrate scope on both 3,3‐disubstituted cyclopropenes and diarylphosphines. The high stereoselectivity is attributed to both the high stability of the Cu(I)‐(R,R)‐QUINOXP* complex in the presence of stoichiometric HPPh2 and the produced phosphines, and the high‐performance asymmetric induction of the Cu(I)‐(R,R)‐QUINOXP* complex. Finally, the method is used for the synthesis of new chiral phosphine‐olefin compounds built on a cyclopropane skeleton, one of which serves as a wonderful ligand in Rh‐catalyzed asymmetric conjugate addition of phenylboronic acid to various α,β‐unsaturated compounds. [ABSTRACT FROM AUTHOR]

Herein, a copper(I)‐catalyzed reaction of diarylphosphines and O‐benzoyl hydroxylamines is developed. In the cases of symmetrical diarylphosphines, a series of aminophosphinites is prepared in high yields. In the cases of unsymmetrical diarylphosphines, an array of P‐chiral aminophosphinites is synthesized in high yields with high enantioselectivity by using a copper(I)‐(R,RP)‐Ph‐FOXAP complex as a chiral catalyst. Based on several control experiments and 31P NMR studies, a two‐electron redox mechanism involving the dynamic kinetic asymmetric transformation of unsymmetrical diarylphosphines is proposed for the copper(I)‐catalyzed asymmetric reaction. Finally, one representative P‐chiral phosphoric amide generated through the oxidation with H2O2 is transformed to a chiral diarylphosphinate in high yield with retained enantioselectivity, which allows further transformations towards various P‐chiral tertiary phosphines. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: A general synthesis of chiral 1,3‐disubstituted allylsilanes is established through copper(I)‐catalyzed asymmetric 1,4‐conjugate silylation of α,β‐unsaturated sulfones and subsequent Julia‐Kocienski olefination. By modification of McQuade's NHC ligand, the catalytic asymmetric conjugate silylation with a broad substrate scope is achieved in high enantioselectivity. The following Julia‐Kocienski olefination proceeds smoothly at room temperature to deliver an array of chiral allylsilanes in moderate yields. More interestingly, a one‐pot asymmetric synthesis with high synthetic efficiency is successfully realized. Utility of the prepared chiral 1,3‐disubsituted allylsilanes is demonstrated in the asymmetric allylation of both aldehyde and aldimine. Finally, an interesting "match and mismatch" phenomenon is observed in the asymmetric allylation of chiral aldehydes. [ABSTRACT FROM AUTHOR]

1,2‐Bisphosphines have been identified as one class of important and powerful chiral ligands in asymmetric catalysis with transition metals. Herein, a copper(I)‐catalyzed asymmetric hydrophosphination of α,β‐unsaturated phosphine sulfides was developed with the assistance of "soft–soft" interaction between copper(I)‐catalyst and the phosphine sulfide moiety, which afforded 1,2‐bisphosphine derivatives with diversified electronic nature and steric hindrance in high to excellent yields with high to excellent enantioselectivity. Moreover, the challenging catalytic asymmetric hydrophosphination/protonation reaction was achieved with excellent enantioselectivity. Strikingly, the dynamic kinetic resolution of racemic diarylphosphines was also successfully carried out with high to excellent diastereo‐ and enantioselectivities. Interestingly, the nucleophilic copper(I)‐diphenylphosphide species was characterized by 31P NMR spectrum and mass spectrum. At last, three products were transformed to chiral 1,2‐bisphosphines, which were employed as ligands in Rh‐catalyzed asymmetric hydrogenation of α‐amino‐α,β‐unsaturated ester. The α‐amino acid derivative was produced in high enantioselectivity, which demonstrated the utility of the present methodology. [ABSTRACT FROM AUTHOR]

The crystallization of polyethylene/fullerene (PE/C60) nanocomposites with different fullerene content was investigated at different temperatures by means of molecular dynamics simulation. It is found that there is a critical temperature for PE/C60 nanocomposite crystallization. The high C60 content makes the low critical temperature. Crystallinity of the equilibrium conformations of PE/5C60 gradually decreases with increasing temperature. Distributions of the dihedral angle along the PE chain, the radius of gyration, and its three Cartesian components are used to characterize changes in the shape and structure of PE chain as temperature increases. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations of polyethylene/fullerene (PE/C60) nanocomposites with different fullerene contents were performed. During the isothermal relaxation process of the PE/C60 nanocomposites, subglobules first appear around C60 molecules and the subglobules coalesce into single globule, then the globule evolves as an ordered structure with the C60 molecules being located at the free surface of the cluster. The simulation results show that the attractive van der Waals interactions control the relaxation process, and as the C60 content increases, the crystallinity of the ultimate structures of PE/C60 nanocomposites decreases. [ABSTRACT FROM AUTHOR]

A series of nine mixed-ligand metal-organic frameworks (MOFs) were prepared by the combination of a bent dipyridyl linker 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole (bpt) and three benzenedicarboxylate isomers respectively. The findings indicate that the isomeric effect of the anionic benzenedicarboxylate is significant in the construction of such network structures which are well regulated by the metal centers.

Novel [Zn.sup.II] and [Cd.sup.II] metal-organic coordination polymers with a versatile building block 5-(4-pyridyl)-1,3,4-oxadiazole-2-thiol (Hpyt) were prepared under different conditions. It is revealed that the versatile anionic ligand pyt behaves as either thioamide or thiolate form and displays a variety of coordination modes in these complexes, which is responsible for their structural diversification.

A new Zn(II)-organic framework with 2,2-bipyridine-5,5-dicarboxylate (bpydc) ligand {[Zn(H2O)(bpydc)]·CH3OH}n has been obtained solvothermally, followed by structural and photophysical characterization. Structural analysis reveals that the distorted Zn2+ octahedra are periodically extended by the ditopic bpydc2- connector, leading to a coplanar grid-like (4 4) layer. The complex exhibits excellent thermal and environmental stability as well as good dispersion in water system. More interestingly, resulting from the efficient ligand to metal charge transfer, the complex has been observed to emit strong blue emission dispersed in water medium enabling the detection of both Cr2 O72- and Fe3+ ions through fluorescence quenching with large quenching constants (1.12×105 M-1 and 2.12×104 M-1) and low limits of detection (0.54 ⛤M and 1.02 μM). These interesting results suggest that the complex can potentially serve as a promising dual-responsive luminescent sensor material for environmental pollutant monitoring. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric vinylogous allylic alkylation of α,β-unsaturated lactones (including coumarins) was achieved with excellent regio- and enantioselectivity. Transformations of the product were carried out by means of the versatile terminal olefin and lactone moieties. The synthetic application of the present methodology was showcased by the asymmetric synthesis of an advanced synthetic Merck intermediate toward a new drug candidate. [ABSTRACT FROM AUTHOR]