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The development of facile tailoring approach to adjust the intrinsic activity and stability of atomically-precise metal nanoclusters catalysts is of great interest but remians challenging. Herein, the well-defined Au8 nanoclusters modified by single-atom sites are rationally synthesized via a co-eletropolymerization strategy, in which uniformly dispersed metal nanocluster and single-atom co-entrenched on the poly-carbazole matrix. Systematic characterization and theoretical modeling reveal that functionalizing single-atoms enable altering the electronic structures of Au8 clusters, which amplifies their electrocatalytic reduction of CO2 to CO activity by ~18.07 fold compared to isolated Au8 metal clusters. The rearrangements of the electronic structure not only strengthen the adsorption of the key intermediates *COOH, but also establish a favorable reaction pathway for the CO2 reduction reaction. Moreover, this strategy fixing nanoclusters and single-atoms on cross-linked polymer networks efficiently deduce the performance deactivation caused by agglomeration during the catalytic process. This work contribute to explore the intrinsic activity and stability improvement of metal clusters.Tailoring catalytic performance of atomically-precise metal nanoclusters catalysts is of great interest but remains challenging. Here, the authors report a co-eletropolymerization strategy to modify well-defined Au8 nanoclusters by single-atom sites to enhance its electrocatalytic activity for the reduction of CO2 towards CO. [ABSTRACT FROM AUTHOR]

New 2D cobalt(II) coordination polymer {[Co3(μ3-dppa)2(4,4'-bipy)2(H2O)4]·7H2O}n (1) was constructed hydrothermally using H3dppa, 4,4'-bipy (H3dppa is 5-(3,4-dicarboxylphenyl) picolinic acid, 4,4'-bipy is 4,4'-bipyridine), and cobalt acetate. Single-crystal X-ray diffraction analyses revealed that compound 1 crystallizes in the monoclinic system, space group P21/c. The adjacent Co(II) ions are bridged by μ3-dppa ligands forming a Co(II) chain subunit. These chain subunits are further linked by 4,4'-bipy ligands into 2D coordination polymers, which are connected through O–H···O hydrogen bonds to form an overall 3D supramolecular structure. Magnetic studies for compound 1 revealed an antiferromagnetic coupling between the adjacent Co(II) centers. [ABSTRACT FROM AUTHOR]

In this study, one Cd(II)-based complex, [Cd3(L)2(bpy)2]n (1) (L3− = 1,3,5-tris(carboxymethoxy)benzene acid), has been hydrothermally synthesized, which displayed three-dimensional (3D) supramolecular framework. The result of fluorescence quenching experiments revealed that complex 1 showed good quenching effect on nitroaromatic compounds, such as p-nitroaniline (4-NA), o-nitroaniline (2-NA), p-nitrophenol (4-NP), and the quenching effect of 4-NA were particularly significant. According to the density functional theory, the remarkable quenching efficiency of 4-NA was caused by an effective electron transport. As a fluorescent probe, Complex 1 can be used to find nitroaromatic chemicals. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two coordination polymers, [Zn(L)(DMF)]n (1) and [Cd(L)(DMF)]n (2), (H2L = 5-(benzimidazole-1-yl)isophthalic acid), have been solvothermally synthesized through reaction of H2L with d10 metal (Zn and Cd) salts. Coordination polymer 1 exhibits a 2D metal–organic structure with [ZnO3N] polyhedron, while coordination polymer 2 possesses a 3D net with [CdO5N]2 cluster. Both coordination polymers exhibit strong fluorescence properties in water, and are capable of being applied to detect the existence of antibiotics by means of fluorescence quenching in aqueous solution. In addition, inhibitory activity was observed for 1 against the Gram-positive staphylococcus epidermidis and the Gram-negative bacteria escherichia coli. [ABSTRACT FROM AUTHOR]

Change detection (CD) is one of the most important application in remote sensing domain. The difference image (DI) generated by traditional change detection methods are sensitive to several factors, such as atmospheric condition changes, illumination variations, sensor calibration, and speckle noise, greatly affecting the detection performance. To avoid the aforementioned problem, in this paper, a novel approach based on superpixel segmentation and image regression is proposed to detect changes between bitemporal synthetic aperture radar (SAR) images. Specifically, the bitemporal images are firstly divided into a number of superpixel pairs under the guidance of segmentation result of a pre-DI. Next, each pixel in pre-event image is reconstructed utilizing its nearest neighbor to reduce the influence of noise. Then, a set of preselected unchanged sample are selected to learn the local regression model and to estimate the post-event image. After that, the final DI can be obtained by measuring the difference between estimated post-event image and the actual one. Finally, the fuzzy c-means (FCM) clustering algorithm is adopted to generate the binary change map. Adequate experiments on four SAR datasets have been tested, and the experimental results compared with the state-of-the-art methods have proved the superiority of the proposed method. [ABSTRACT FROM AUTHOR]

Two coordination polymers, namely {[Mn2(HL)2(bpe)(H2O)8]·5H2O}n (1) and {[Ni3(L)2(bpe)3(H2O)6]·3H2O}n (2) (H3L = 1,3,5-tris(carboxymethoxy)benzene, bpe = 1,2-bis(4-pyridyl)ethylene), have been hydrothermally synthesized. In compound 1, two Mn2+ ions are linked by two HL2− ligands into rings. Adjacent rings are linked through hydrogen bonding between carboxylic groups and water molecules to produce a three-dimensional supramolecular network, which shows channels along the b axis that are occupied by the free bpe molecules. Compound 2 possesses a 3D architecture, constructed from Ni-bpe chains and L3− linkers. The 3D architecture is further consolidated by the hydrogen-bonding interactions. The magnetic properties of complexes 1 and 2 have been investigated. Antiferromagnetic interactions were observed for complexes 1 and 2. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The aim of this study was to investigate the association between specific contraceptives use and reproductive tract infections (RTIs). Study design: Participants consisted of 52,481 rural married women of reproductive age identified from a cross-sectional study in Anhui Province of China. The questionnaire, gynecological examination, and laboratory inspection were used to collect data. The subgroup analysis was performed to estimate the effect of the specific contraceptives on the specific RTIs. Results: A total of 49,970 (95.2 %) women used contraceptive methods and 31,390 (59.8 %) women had at least one RTI. Overall, use of intrauterine device (IUD), condom, female sterilisation, rhythm method, and oral contraceptive (OC) were associated with RTIs. In the subgroup analysis, IUD use was a risk factor for endocervicitis, bacterial vaginosis (BV), and trichomoniasis; condom, rhythm method, and OC were associated with endocervicitis; female sterilisation was associated with endocervicitis and trichomoniasis. Moreover, male sterilisation was associated with endocervicitis; withdrawal was a protective factor for endocervicitis and a risk factor for trichomoniasis; subdermal implant was associated with candidiasis and pelvic inflammatory disease (PID). Conclusions: All the contraceptive methods may lead to the RTIs. A properly assessment for contraceptive methods use is needed for female reproductive health. [ABSTRACT FROM AUTHOR]

Four new coordination polymers [Zn(3-Nbdc)(bpa)] ( 1), [Cd(3-Nbdc)(bpa)(HO)] ( 2), [Zn(3-Nbdc)(bpp)] ( 3) and {[Zn(3-Nbdc)(bpe)]·1.5HO} ( 4) (3-Nbdc = 3-nitrobenzene-1,2-dicarboxylate, bpa = 1,2-bi(4-pyridyl)ethane, bpp = 1,3-bis(4-pyridyl)propane and bpe = 1,2-bi(4-pyridyl)ethene), were synthesized hydrothermally and characterized structurally by single crystal X-ray diffractions, elemental analysis and infrared spectroscopy. Complexes 1 and 3 exhibit three-dimensional (3D) metal-organic frameworks with the (6) dia topology and (6·8) cds topology, respectively, and both of them contain metal-carboxylate helix chains. Compounds 2 and 4 show 2D → 3D interpenetrated networks with (4,4) grid layers and 2D layer, respectively, and both of them contain metal-carboxylate binuclear units. The thermal stabilities and fluorescence properties for complexes 1- 4 are investigated. The blue-shift of the luminescent wavelength in 2 may be due to the absence of interligand π··· π effects compared with that of other three compounds, but there exist the strong face-to-face π··· π interactions in 1 and edge-to-face π··· π interactions in 3 and 4, showing a certain degree of interchromophore coupling interaction. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and the third most common cause of cancer-related deaths. The objective of our research was to develop effective agents against HCC. Here, we have synthesized a series of anilinoquinoline derivatives. Based on a MTT assay and qRT-PCR in human Huh-7 hepatoma cells, we observed that 2-(2,6-dimethylanilino)quinoline ( 9) and 2-(3-benzenecarbonylanilino)quinoline ( 23) exhibited good antitumor activity. Besides, the polo-like kinase 1 (PLK1) positively correlated with aggressiveness of tumors and polo-like kinase 3 (PLK3) regarded as a tumor suppressor gene are serine/threonine kinases that play an essential role in carcinogenesis. Our results indicated that 2-anilinoquinoline ( 6) and 2-(3,5-dimethoxyanilino)quinoline ( 16) may decrease the expression levels of PLK1 gene, as well as increase the expression levels of PLK3 gene. We suggested this series of synthesized anilinoquinolines be promising to develop as novel regulating PLK molecular. Further, structural modification and the molecular mechanism of these compounds as a candidate are underway. [ABSTRACT FROM AUTHOR]

Intracytoplasmic sperm injection (ICSI) is commonly used to solve male infertility problems. Previous studies showed that early environmental exposure of an embryo may influence postnatal development. To detect whether ICSI operations affect the reproductive health of a male or his offspring, we established assisted reproductive technologies (ART) conceived mouse models, and analyzed gene expression profiles in the testes of both ICSI and naturally conceived (NC) newborn F mice using micro-array analysis. Among the differentially expressed genes, we focused on the expression of eight male reproduction-related genes. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) was used to analyze the expression of these genes in the testes of both adult and old F generation mice and adult F generation mice. Our results showed that down-regulated and somatic cell-expressed genes in newborn mice retained their differential expression patterns in adult and old F generation individuals, implying the persistence and fetal origin of the alteration in the expression of these genes. The intergenerational transmission of differential gene expression was observed, but most changes tended to be reduced in adult F generations. Controlled ovarian hyperstimulation (COH) and in vitro fertilization (IVF) mice models were added to explore the precise factors contributing to the differences in ICSI offspring. The data demonstrated that superovulation, in vitro culture, and mechanical stimulation involved in ICSI had a cumulative effect on the differential expression of these male reproductive genes. [ABSTRACT FROM AUTHOR]

An association between assisted reproductive technology (ART) and neurobehavioral imprinting disorders has been reported in many studies, and it seems that ART may interfere with imprint reprogramming. However, it has never been explored whether epigenetic errors or imprinting disease susceptibility induced by ART can be inherited transgenerationally. Hence, the aim of this study was to determine the effect of in vitro fertilization and embryo transfer (IVF-ET) on transgenerational inheritance in an inbred mouse model. Mice derived from IVF-ET were outcrossed to wild-type C57BL/6J to obtain their female and male line F2 and F3 generations. Their behavior, morphology, histology, and DNA methylation status at several important differentially methylated regions (DMRs) were analyzed by Morris water maze, hematoxylin and eosin (H&E) staining, and bisulfite genomic sequencing. No significant differences in spatial learning or phenotypic abnormality were found in adults derived from IVF (F1) and female and male line F2 and F3 generations. A borderline trend of hypomethylation was found in H19 DMR CpG island 3 in the female line-derived F3 generation (0.40±0.118, P=0.086). Methylation status in H19/Igf2 DMR island 1, Igf2 DMR, KvDMR, and Snrpn DMR displayed normal patterns. Methylation percentage did not differ significantly from that of adults conceived naturally, and the expression of the genes they regulated was not disturbed. Transgenerational integrity, such as behavior, morphology, histology, and DNA methylation status, was maintained in these generations, which indicates that exposure of female germ cells to hormonal stimulation and gamete manipulation might not affect the individuals and their descendents. [ABSTRACT FROM AUTHOR]

A new chelating radical ligand, IMMeBzIm (IMMeBzIm = 2-{2′-[(l′-methyl)benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl) and its copper(II) complex [Cu(IMMeBzIm)2(ClO4)]·(ClO4) have been prepared and characterized by IR, magnetic and single-crystal X-ray analysis. In the crystal structures, both free IMMeBzIm and the complex crystallize in monoclinic space groups P2(1)/c and C2/c, respectively. The structure of IMMeBzIm consists of mononuclear molecules. In the complex, the coordination geometry around copper is a distorted square pyramid, and the apical position is occupied by one oxygen atom of ClO4 − anion. A 1-D polymer is formed through intermolecular H-bond interactions. The variable-temperature magnetic susceptibility of the free IMMeBzIm suggests weak antiferromagnetic coupling with J = −1.12 cm−1 where the spin Hamitonian is defined as Ĥ = −2 JŜ 1 Ŝ 2 between radical and radical. [ABSTRACT FROM AUTHOR]

Oocyte quality has long been considered as a main limiting factor for in vitro fertilization (IVF). In the past decade, extensive observations demonstrated that the mitochondrion plays a vital role in the oocyte cytoplasm, for it can provide adenosine triphosphate (ATP) for fertilization and preimplantation embryo development and also act as stores of intracellular calcium and proapoptotic factors. During the oocyte maturation, mitochondria are characterized by distinct changes of their distribution pattern from being homogeneous to heterogeneous, which is correlated with the cumulus apoptosis. Oocyte quality decreases with the increasing maternal age. Recent studies have shown that low quality oocytes have some age-related dysfunctions, which include the decrease in mitochondrial membrane potential, increase of mitochondrial DNA (mtDNA) damages, chromosomal aneuploidies, the incidence of apoptosis, and changes in mitochondrial gene expression. All these dysfunctions may cause a high level of developmental retardation and arrest of preimplantation embryos. It has been suggested that these mitochondrial changes may arise from excessive reactive oxygen species (ROS) that is closely associated with the oxidative energy production or calcium overload, which may trigger permeability transition pore opening and subsequent apoptosis. Therefore, mitochondria can be seen as signs for oocyte quality evaluation, and it is possible that the oocyte quality can be improved by enhancing the physical function of mitochondria. Here we reviewed recent advances in mitochondrial functions on oocytes. [ABSTRACT FROM AUTHOR]

Customer requirements analysis is the key step for product variety design of mass customization(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD process and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

Many existing product family design methods assume a given platform, However, it is not an intuitive task to select the platform and unique variable within a product family. Meanwhile, most approaches are single-platform methods, in which design variables are either shared across all product variants or not at all. While in multiple-platform design, platform variables can have special value with regard to a subset of product variants within the product family, and offer opportunities for superior overall design. An information theoretical approach incorporating fuzzy clustering and Shannon’s entropy was proposed for platform variables selection in multiple-platform product family. A 2-level chromosome genetic algorithm (2LCGA) was proposed and developed for optimizing the corresponding product family in a single stage, simultaneously determining the optimal settings for the product platform and unique variables. The single-stage approach can yield improvements in the overall performance of the product family compared with two-stage approaches, in which the first stage involves determining the best settings for the platform and values of unique variables are found for each product in the second stage. An example of design of a family of universal motors was used to verify the proposed method. [ABSTRACT FROM AUTHOR]

A stainless steel fiber was coated with a gate-opening controlled metal-organic framework ZIF-7 via a sol-gel method and applied to the solid-phase microextraction of aldehydes (hexanal, heptanal, octanal, nonanal, decanal) from exhaled breath by lung cancer patients. The effects of temperature and time on the sorption and desorption were optimized. Under optimum condition, the modified fiber displays enrichment factors (typically ranging from 300 to 10,000), low limits of detection (0.61-0.84 μg L−1), and wide linear ranges of hexanal, heptanal (5-500 μg L−1) and octanal, nonanal, decanal (10-1000 μg L−1). The high extraction capability for aldehydes is thought to result from (a) the combined effects of the large surface area and the unique porous structure of the ZIF-7, (b) the hydrophobicity and gate-opening effect of the sorbent, (c) the high selectivity of the window, and (d) the presence of unsaturated metal-coordination sites. The coated fiber is thermally stable and can be re-used >150 times. The relative standard deviation (RSD) for six replicate extractions using a single fiber ranged from 1.4-15.3% for intra-day and 2.4-16.1% for inter-day. The fiber-to-fiber reproducibility for three fibers prepared in parallel was in the range of 2.4-12.6% (RSD). The method was applied to the extraction of aldehydes from real samples and to the quantitation by gas chromatography. Recoveries from spiked samples ranged from 84 to 113%.A metal-organic framework ZIF-7 coated stainless steel fiber was prepared via sol-gel method. The self-made fiber was applied in the solid phase microextraction of aldehydes from exhaled breath of lung cancer patients. [ABSTRACT FROM AUTHOR]

We have performed an unbiased structure search for a series of neutral and anionic FeL4 (L = BO2, CN, NO2, NO3, OH, CH3, NH2, BH4 and Li2H3) clusters using the CALYPSO (Crystal structure Analysis by Particle Swarm Optimization) structure search method. To probe the superhalogen properties of neutral and anionic FeL4 clusters, we used density-functional theory with the B3LYP functional to examine three factors, including distribution of extra electron, pattern of bonding and the nature of the ligands. Theoretical results show that Fe(BO2)4, Fe(NO3)4 and Fe(NO2)4 can be classified as magnetic superhalogen due to that their electron affinities even exceed those of the constituent ligands. The magnetic moment of Fe atom is almost entirly maintained when it is decorated with various ligands except for neutral and anionic (Li2H3)4. Moreover, the current work is also extended to the salt moieties formed by hyperhalogen/superhalogen anion and Na+ ion. It is found that these salts against dissociation into Na + FeL4 are thermodynamic stable except for Na[Fe(OH)4]. These results provides a wealth of electronic structure information about FeL4 magnetic superhalogens and offer insights into the synthesis mechanisms. [ABSTRACT FROM AUTHOR]