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The latest progress in 2D ultrathin nanomaterials used for photocatalysis has been summarized from a sustainable synthesis perspective. Various synthetic strategies and approaches have been discussed and compared.

The one-dimensional oxidized porous carbon nitride rods via de-aromatization of the heptazine network in bulk g-C3N4 exhibit excellent photocatalytic activity towards the degradation of rhodamine B compared with that of bulk g-C3N4.

Converting sustainable solar energy into hydrogen energy over semiconductor-based photocatalytic materials provides an alternative to fossil fuel consumption. However, efficient photocatalytic splitting of water to realize carbon-free hydrogen production remains a challenge. Heterojunction photocatalysts with well-defined dimensionality and perfectly matched interfaces are promising for achieving highly efficient solar-to-hydrogen conversion. Herein, we report the fabrication of a novel type of protonated graphitic carbon nitride (PCN)/Ti3C2 MXene heterojunctions with strong interfacial interactions. As expected, the two-dimensional (2D) PCN/2D Ti3C2 MXene interface heterojunction achieves a highly improved hydrogen evolution rate (2181 μmol·g−1) in comparison with bulk g-C3N4 (393 μmol·g−1) and protonated g-C3N4 (816 μmol·g−1). The charge-regulated surfaces of PCN and the accelerated charge transport at the face-to-face 2D/2D Schottky heterojunction interface are the major contributors to the excellent hydrogen evolution performance of the composite photocatalyst.

Two-dimensional graphitic carbon nitrides (2D g-C3N4) are promising photocatalysts for water splitting to hydrogen due to their non-toxicity and high stability. However, the bulk g-C3N4 has some intrinsic drawbacks, such as rapid electron–hole recombination and low charge-carrier mobility, resulting in poor photocatalytic activity. Here, 2,4-diamine-6-phenyl-1,3,5-triazine was employed as a precursor to regulating the assembly of melamine and cyanuric acid in water. The resulting g-C3N4 not only improved the visible light absorption and electron–hole separation but also provided more catalytic sites for enhanced photocatalytic hydrogen evolution. The modified g-C3N4 (CNP10-H) showed a hydrogen-releasing rate of 2184 μmol·g−1·h−1, much higher than the bulk g-C3N4.

Two-dimensional polymeric graphitic carbon nitride (2D g-C3N4) nanostructures have emerged as a very promising family of photocatalysts for hydrogen evolution from water. Nonetheless, fast recombination of photogenerated charge carriers and the sluggish kinetics of hydrogen evolution reaction (HER) result in unsatisfied solar-to-hydrogen efficiency. It is thus greatly encouraging to explore low-cost and high-performance co-catalysts to accelerate the charge transport and to improve the catalytic performance. In this work, for the first time, we report on the fabrication of ultra-small zero-dimensional (0D) FeP nanodots anchored on layered 2D g-C3N4 nanosheets with well-defined nanostructures and intimate 0D/2D contact interface. The outstanding feature of the material is that the obtained multidimensional heterojunction photocatalysts reveal highly efficient visible-light-responsive HER performance in the absence of noble metals. Under an optimal percentage of 4 wt. % FeP, the FeP/g-C3N4 hybrid showed a remarkable hydrogen-evolving rate of 215 μmol g−1 h−1 and excellent recycling stability, surpassing noble-metal Pt modified g-C3N4 (155 μmol g−1 h−1). The enhancement in HER activity is attributed to the synergistic effects of FeP nanocrystals on the improvement of light-harvesting property in the visible light region and the acceleration of charge carrier dynamics by well-constructed interfaces.

Pristine graphitic carbon nitride (g-C3N4) suffers from poor photocatalytic activity due to its limited light adsorption, small specific surface area and feasible recombination of photogenerated charge carriers. One practical approach to solve the problem of low solar-to-hydrogen efficiency is nanostructuring the morphology of g-C3N4 to enhance its light-harvesting property and boost the rate of charge-carrier transportation. Here, we present a strategy to optimize the textural properties and catalytic performance of g-C3N4 via using oxamide (OA) as a chemical modifier in the precursor solution, which significantly make the light absorption edge shift from 440 to 650 nm. Moreover, the nanostructure of the resultant g-C3N4 can be easily tuned with increasing the amount of oxamide. The morphological features of g-C3N4 materials change from sheet-like structure to tubular structure, porous nanotube and eventually interconnected porous sheet. More interestingly, the unique g-C3N4 nanostructure offers advantages of a broader solar absorption spectrum and accelerates charge carrier dynamics that are favorable for advancing photocatalytic performance. The findings provide insightful information that can be used to understand the structure-property relationship in g-C3N4 nanostructures for improved solar-to-fuel conversion.

Rationally designing heterojunction photocatalysts with well-defined nanostructures and intimate interfacial contact is highly significant for improving the photocatalytic hydrogen evolution reaction (HER) activity. Here, we report on the fabrication of one-dimensional (1D) CdS/two-dimensional (2D) MoSe2 heterostructure for efficient photocatalytic hydrogen production. It is revealed that layered MoSe2 nanosheets are randomly anchored on CdS nanorods via an in-situ solvothermal process. When the loading content was kept at 10 wt%, the mix-dimensional nanohybrids exhibited a highly improved hydrogen-evolving rate up to 25.8 mmol g −1 h −1, which is 4 times higher than that of pristine CdS nanorods. The apparent quantum efficiency (AQE) of the optimized hybrid catalyst CM-10 is determined to be around 30% at 420 nm. The enhancement of photocatalytic HER activity can be attributed to the synergistic effect between 1D CdS nanorods and 2D MoSe2 nanosheets, which enables the accelerated electron-hole separation and more efficient interfacial charge transport. The findings in this study imply that, through morphology control and interfacial engineering, the efficiency and long-term stability of heterojunction photocatalysts toward hydrogen production from water splitting can be effectively tuned, providing new insights into the development of robust and high-performance visible light photocatalysts.

Environmentally friendly polypyrrole (PPy) catalysts with conjugated nanostructures for superior photophysical and photoelectric applications are developed. The high coplanar structure via α-α connection is benefit for the transferring of photo-induced electron and improving the life of the light generated carrier. Importantly, the energy level structure of conjugated polymers was obtained via theoretical calculation and the photocatalytic mechanism of PPy photocatalyst was illuminated in detail. O2− are the main radical responsible for the degradation of MO. Moreover, conjugated PPy photocatalysts are stable with cycling. Compared to P25 and g-C3N4, PPy showed excellent photocatalytic performance for degradation of organic pollutants in full spectrum and visible light, the reaction rate constants of PPy are 4.27 and 5.31 times as much as the P25, respectively. Furthermore, PPy also exhibited effective photocatalytic performance towards different organic pollutants. These results obviously open interesting perspectives of using conjugated polymer and provide theoretical guidance for designing new organic photocatalysts to solve the energy and environment issues.

Biochar application to agricultural soils has been reported to reduce nutrient leaching and ameliorate degraded soils. However, few studies exist that verify decreased nutrient leaching in biochar-amended riparian soils or that identify the mechanism for nutrient retention. Column leaching experiments were conducted to investigate the effects on nutrient leaching and retention of rice husk biochar additions at varying rates (0%, 1%, 2%, 5%, and 10% by weight) following application of fertilizer (NH4NO3 and KH2PO4) to a subtropical riparian soil from the Taihu Lake watershed of China over a 24-week incubation. We found that increasing levels of biochar decreased cumulative amounts of leachate NH4-N by 28 to 63%, NO3-N by 23% to 84% and dissolved organic nitrogen by 15% to 46%, while increasing leaching of PO4-P by 43% to 108%. Total nitrogen (N) and available phosphorus (P) contents significantly increased in the biochar-amended soil. The significant increase in soil microbial biomass N after biochar addition suggests that fertilizer N was retained by microbial cycling. The decrease in NH4-N and increase in NO3-N in biochar-amended soil imply that nitrification was enhanced with biochar addition. Biochar treatments increased soil available P due either to the release of soluble P from biochar or to enhanced P mineralization by soil microbial biomass. These results indicate that addition of biochar increased the capacity of the riparian soil studied to provide plant available nutrients and reduce N leaching.

With the ambition of solving the challenges of the shortage of fossil fuels and their associated environmental pollution, visible-light-driven splitting of water into hydrogen and oxygen using semiconductor photocatalysts has emerged as a promising technology to provide environmentally friendly energy vectors. Among the current library of developed photocatalysts, organic conjugated polymers present unique advantages of sufficient light-absorption efficiency, excellent stability, tunable electronic properties, and economic applicability. As a class of rising photocatalysts, organic conjugated polymers offer high flexibility in tuning the framework of the backbone and porosity to fulfill the requirements for photocatalytic applications. In the past decade, significant progress has been made in visible-light-driven water splitting employing organic conjugated polymers. The recent development of the structural design principles of organic conjugated polymers (including linear, crosslinked, and supramolecular self-assembled polymers) toward efficient photocatalytic hydrogen evolution, oxygen evolution, and overall water splitting is described, thus providing a comprehensive reference for the field. Finally, current challenges and perspectives are also discussed.

Background Prostate cancer (PCa) is a leading cause of cancer morbidity and mortality in men worldwide; however, PCa incidence and mortality rates vary widely across geographic regions and ethnic groups. The current study was designed to elucidate the pivotal factors involved in PCa occurrence and development. Methods We performed RNA sequencing on the prostate tumor and adjacent normal tissues from Chinese PCa patients. Genes identified via genome‐wide expression profile analysis were validated by quantitative reverse‐transcription polymerase chain reaction and immunohistochemistry. Hypermethylation of CpG islands was assessed by nested methylation‐specific PCR. Whole genome microarray analysis was performed using an Affymetrix GeneChip. Results We identified nine possible abnormally expressed genes (P

It is highly desirable to design an efficient photocatalysis system via manipulating electrons migration pathways for optimal hydrogen production from water splitting. Herein, flower-like MoSe2 has been employed as the co-catalyst to couple with cubic CdS nanoparticles for the in-situ construction of MoSe2/CdS heterojunction photocatalysts. Experimental investigations suggest that the photogenerated electrons can transfer across a space charge region between the MoSe2/CdS through the S–Mo–Se bonding, resulting in faster charge carriers separation and hence more long-lived electrons to participate in the hydrogen evolution reaction (HER). These insights are also supported by density functional theory (DFT)-based theoretical calculation. The dynamics of the photo-excited electrons was also investigated by ultrafast transient absorption spectroscopy. Furthermore, MoSe2 can afford more active sites for absorbing the protons for H2-evolution reactions, thereby accelerating the sluggish hydrogen evolution kinetics. Therefore, under visible-light irradiation, a remarkably enhanced photocatalytic H2 generation has been achieved in the MoSe2/CdS heterojunction (4.7 mmol g−1 h−1) compared to mechanically mixed sample (3.3 mmol g−1 h−1) and Pt-decorated CdS (1.3 mmol g−1 h−1). The external quantum efficiency of the MoSe2/CdS heterojunction toward HER has been determined to be 15.6% at 450 nm. This work not only provides a rational design for utilizing abundant elements to develop high-performance photocatalysts, but also pave the way to understand the photogenerated carriers transfer dynamics.

Objective: Shared genetic variants in ADIPOR1 have been identified as closely related to coronary artery disease (CAD), type 2 diabetes (T2D), and T2D with CAD susceptibility, suggesting that these variants are strong candidates for the common soil hypothesis. Therefore, it is essential to analyze the relationship between ADIPOR1 variants and the susceptibility to CAD, T2D, and T2D with CAD in other populations. Materials and Methods: A case–control study was conducted which included three case cohorts [CAD (n = 316), T2D (n = 295), T2D with CAD (n = 302)], and a control cohort (n = 268) from a population in northeast China. Six ADIPOR1 single-nucleotide polymorphisms were genotyped by high-resolution melting and polymerase chain reaction–restriction fragment length polymorphism. Results: We confirmed that the shared variant, rs3737884*G, in ADIPOR1 is associated with CAD, T2D, and T2D with CAD (p-value range: 6.54E-6–1.82E-5, odds ratio [OR] range: 1.770–1.844) and that rs16850797*C is associated with T2D and T2D with CAD (p-value range: 0.001–0.001, OR range: 1.529–1.571). We also found that a novel shared variant, rs7514221*C, is associated with an increased susceptibility to CAD, T2D, and T2D with CAD (p-value range: 0.002–0.004, OR range: 1.194–2.382) in this population. Conclusions: ADPOR1 variants, rs3737884*G and rs7514221*C, may be shared risk factors associated with CAD, T2D, and T2D with CAD in a population of northeast China.

Developing earth-abundant photocatalysts with high activity and long term-stability for solar-driven hydrogen evolution reaction (HER) is an old but still tough challenge in the photocatalytic water splitting. Despite the remarkable progress that has been made in the preparation and modification of graphitic carbon nitride (g-C3N4), the most popular metal-free photocatalyst, there still exists a need to explore novel synthetic approaches for the controllable synthesis of g-C3N4-based photocatalytic materials toward improved HER performance. Herein, we propose a solvent-mediated supramolecular assembly approach to fabricate modified g-C3N4 nanoarchitectures based on the asymmetric polymerization of three precursors, melamine, cyanuric acid and barbituric acid. The resulting g-C3N4 nanostructure assisted by the supramolecular preorganization of precursors is favorable for visible light harvesting, charge carrier separation and solar HER performance. The hydrogen-evolution rate of the modified g-C3N4 sample derived from ethanol is three times higher than that of g-C3N4 calcined from the symmetric polymerization of melamine and cyanuric acid, implying the important role of barbituric acid. More importantly, the effects of solvent polarity on the morphology, composition, charge carrier dynamics and HER activity were evaluated.

Photocatalytic water splitting by heterojunction nanostructures is considered as one of the most favorable pathways for direct solar-to-hydrogen conversion. High-efficiency solar hydrogen production demands an effective separation of charge carriers and their rapid transport to the interface, whereas the charge-transfer pathway in heterojunction photocatalysts is largely elusive. Herein, 2D CdS/2D MXene Schottky heterojunctions are synthesized via a sequence of electrostatic self-assembly process and solvothermal method. The composite photocatalysts exhibit highly efficient and robust hydrogen-evolving performance, far superior than the pristine CdS nanosheets. Furthermore, density functional theory (DFT) calculations are adopted to unveil the charge-transport pathway. It is revealed that an intimate Schottky contact is constructed between CdS and MXene, which further steers the formation of charge flow and expedites the charge migration from CdS to MXene, thus suppressing the recombination of photogenerated charge carriers and boosting the photocatalytic activity for hydrogen evolution.

To explore an efficient electron extraction cocatalyst remains an ongoing task to address the rapid recombination and low transfer rate of electron–hole pairs in photocatalytic water splitting. Herein, it is demonstrated that 2D MXene (Ti3C2) with high electron conductivity can act as an effective electron transfer and transport medium after being hybridized with Ag3PO4, a well-documented photocatalyst for oxygen evolution. The obtained Ag3PO4/MXene photocatalysts exhibit a significantly high photocatalytic water oxidation activity under visible light illumination. The optimized hybrid shows a remarkable oxygen-evolving concentration (35.8 μmol L−1), which is 2.6 times higher than that of pure Ag3PO4 nanoparticles. Unprecedentedly, the Ag3PO4/MXene hybrid exhibits a further improved oxygen evolution rate without using the electron sacrificial agent, implying that Mxene nanosheets may act as an electron “pool” that in situ consumes the photogenerated electrons. Other characterizations reveal that the hydrophilic functional groups on the surface of MXene favor the interaction of the photocatalyst with water and in the meantime inhibit the self-corrosion of Ag3PO4 under illumination.

Benefiting from excellent metallic conductivity, full-spectrum solar energy absorption and rich active sites on the surface, atomically thin two-dimensional transition metal carbide (2D MXene) shows great promise in improving solar-to-hydrogen efficiency and has drawn intense interest in the field of photocatalysis. However, controllable construction of ultrathin 2D MXene-based heterojunction photocatalysts still remains a significant challenge. Herein, one-dimensional (1D) CdS nanorod/2D MXene nanosheet heterojunctions with well-defined nanostructures and strong interfacial coupling are fabricated by in situ assembling solvothermally-generated CdS nanorods on ultrathin Ti3C2 MXene nanosheets. Due to their specific interface characteristics, 1D/2D Schottky heterojunction is capable of providing accelerated charge separation and a lower Schottky barrier for solar-driven hydrogen evolution from water splitting. As expected, the Schottky-based photocatalyst is 7-fold more active in the illuminated hydrogen evolution reaction (HER) than pristine CdS nanorods, implying the synergistic effects between n-type semiconductor CdS and highly conductive 2D Ti3C2 MXene nanosheets.

Searching for highly efficient photocatalysts for water oxidation is the footstone for the development of overall water splitting systems and has been actively pursued. The construction of artificial Z-scheme heterojunction photocatalysts has been conclusively proven to be effective in boosting charge transport property and in improving the OER performance. Herein, Ag3PO4 particles anchored on modified crispy g-C3N4 flakes have been successfully fabricated. KOH-assisted surface modification of g-C3N4 flakes and intimate interfacial contact favor the accelerated charge transfer and highly improved OER efficiency. Ultrafast spectroscopy results reveal that modified g-C3N4 with crispy nanostructures possesses more trap-induced long-lived photogenerated holes, which are extremely helpful to combine with photo-generated electrons from the conduction band (CB) position of Ag3PO4 via the specific Z-scheme configuration, leaving more holes in the valence band (VB) of Ag3PO4 for the enhanced OER. Superb oxygen-evolving performance highlight the great promise of Z-scheme Ag3PO4-based heterojunctions in solar-driven photocatalytic water splitting.

The photophysical properties of 2,2′-bis-(4-alkoxyphenyl)-bi-1,3,4-oxadiazole (BOXD- n ), have been studied by a combination of spectroscopic techniques and theoretical calculations. Interestingly, strong fluorescence red-shift in polar solvents was observed in this highly symmetric molecule, which indicates an efficient charge transfer (CT) occurred in the excited state. The change of molecular dipole moment between the ground state and CT excited state was calculated to be 9.9 D. Theoretical calculations at Density Functional Theory level revealed that the first singlet excited state of BOXD- n shows both π – π * and CT characters. Clear evidence for charge transfer from alkoxy benzene to the central bi-1,3,4-oxadiazole group can be observed by analysing the atomic charge and electron density change, though it is not significant. Since BOXD-1 retained a planar conformation and became more quinoid-like in the excited state, a planar intramolecular charge transfer is assigned for it. By further comparing these results with the half molecule terminated by CH 3 group (2-tetradecyloxyphenyl, 5-methyl-1,3,4-oxadiazole), it could be concluded that intramolecular charge transfer property was enhanced in this DAAD arrangement of BOXD- n .

Endothelial tight junction is a crucial intracellular junctional structure that controls paracellular permeability across vascular endothelium. Oxidative stress-mediated elevation in endothelial permeability is associated with pathogenesis of several cardiovascular diseases. In the present research, the regulation of farrerol on occludin, a transmembrane proteins associated with endothelial tight junction, was investigated in hydrogen peroxide-induced human endothelium-derived EA.hy926 cells. Western blot analysis demonstrated that H2O2 exposure caused a significant decrease in occludin expression, but had little effect on ZO-1 expression, and the decrease of occludin expression was significantly attenuated by farrerol in a dose-dependent manner. Meanwhile, immunofluorescent staining assay also demonstrated that the loss of occludin expression induced by H2O2 exposure was restored by farrerol pretreatment. Further investigations showed that farrerol prevented H2O2-induced activation of extracellular signal-regulated kinase (ERK) 1/2 in a dose-dependent manner. The use of U0126, a specific inhibitor of MEK1/2, proved that H2O2-induced decrease of occludin in EA.hy926 cells was likely associated with activation of ERK1/2, which indicated that the regulation of farrerol on occludin expression in H2O2-induced EA.hy926 cells was likely related to the modulation of ERK1/2 activation. In conclusion, the present study demonstrates for the first time that farrerol has potential effects on oxidative stress-induced endothelial tight junction disruption and suggests that farrerol is a potential candidate for the intervention of endothelial permeability-associated cardiovascular diseases.

The compound N, N’-bis (4-n-alkylo-xybenzoyl) hydrazine (4D16), containing a dihydrazide unit in the rigid core, had been systematically investigated in view of their gelation behaviors, topological structures, and gelation formation processes. It has been demonstrated that 4D16 shows strong gelation ability in nonpolar solvents such as benzene and toluene. The xerogels consist of entangled ribbons with the width about 5 μm. According to X-ray diffraction (XRD), cubic structure is revealed in the benzene system, whereas layered structure is observed in toluene system. The morphological observations and kinetic studies by fluorescence spectroscopy as well as rheological study further reveal that self-assembly processes during gelation also differs. Radius fibers with a fractal dimension about 1.4 were observed in benzene system; whereas, less open fibrillar structures with fractal dimension approximately 1.1 were revealed for toluene system. The present results appear to represent that the molecular packin...

Background: The single nucleotide polymorphism (SNP) rs1465618 in THADA at 2p21 has been identified as being associated with prostate cancer (PCa) risk in Europeans; however, it is not clear whether the SNP is related to PCa risk in multiple populations. We investigated the association of rs1465618 in THADA with PCa in a Chinese population and carried out a meta-analysis in multiple populations, testing the relevance of this SNP for PCa risk. Patients and Methods: We genotyped the SNP using high resolution melting (HRM) analysis and assessed its association with PCa risk in a case-control study of 289 PCa patients and 288 controls in a Chinese population. A meta-analysis was carried out with 36,313 PCa patients and 36,485 controls to evaluate the association of rs1465618 with PCa risk in multiple populations. Results: rs1465618 in THADA was significantly associated with PCa risk (p = 0.026; odds ratio (OR) 1.327, 95% confidence interval (CI) 1.035-1.700). Furthermore, the rs1465618 variant genotype was associated with PCa aggressiveness (p = 0.044; OR = 2.053, 95% CI = 1.015-6.602) in the Chinese population. The meta-analysis showed that rs1465618 was significantly associated with PCa risk in multiple populations (p = 1.0×10-8; OR = 1.127, 95% CI = 1.085-1.171). Conclusion: Our results showed that rs1465618 in THADA may be a shared susceptibility variant for PCa in multiple populations. THADA gene polymorphisms may impact PCa susceptibility and progression.

A bi-1,3,4-oxadiazole derivative (BOXDH-T12) showed intramolecular charge transition at concentrations lower than 1 × 10 −5 mol/L. The self-assembling behaviors of BOXDH-T12 depended on solvents that it self-assembled into H-aggregates in alcohols and slipped packing aggregates in DMSO. FTIR, 1 H NMR and TGA results revealed that strong gelator–gelator hydrogen bonding interaction induced H-aggregation of BOXDH-T12 in alcohols and the interactions between DMSO and BOXDH-T12 molecules caused a slipped stacking. BOXDH-T12 can gel the mixtures of DMSO and ethanol through a cooperative effect of the hydrogen bonding, van der Waals interaction and π – π stacking forces, furthermore, helical ribbons could be observed in DMSO/ethanol due to DMSO molecule interacting. In alcohols, solvophobic/solvophilic effect plays a critical role in gelation behaviors.

A non-liquid crystal compound (4-POXD-6) containing the 1,3,4-oxadiazole group and pyridyl (py) group was synthesized. And a series of supramolecular mesogenic complexes were obtained by mixing 4-POXD-6 and 4-alkoxybenzoic acids (Cn, n=6, 8, 12). The liquid crystalline properties of 4-POXD-6/Cn (n=6, 8, 12) were investigated by means of differential scanning calorimetry, polarized optical microscopy, and wide-angle X-ray diffraction. It was found that 4-POXD-6/Cn (6, 8) display monotropic nematic and smectic A phases, while 4-POXD-6/C12 exhibits a SmX phase in the heating process and a SmA phase in the cooling run. Variable-temperature FTIR spectroscopic studies revealed hydrogen bonds existed in both crystalline and liquid crystalline phases.

A new series of liquid crystalline hydrazide derivatives N-4-(alkoxyphenyl)-N'-4-[(4-hydroxyphenyl)azophenyl] benzohydrazide (BNB-n, n = 8, 12, 14) was designed and synthesised. Based on the results of variable temperature 1H NMR and FT-IR spectroscopy, a supramolecular assembly motif of BNB-n through both axial intermolecular hydrogen bonds between hydroxyl groups and lateral hydrogen bonds between hydrazide groups was proposed. Interestingly, BNB-n (n = 12, 14) with longer terminal chains displayed anticlinic bilayer smectic C mesophase (SmC2a). In order to reveal the effect of axial hydrogen bonding between hydroxyl groups on the formation of this unique mesophase, the hydroxyl group was replaced by a methoxy group to form N-4-(alkoxyphenyl)-N'-4-[(4-methoxyphenyl)azophenyl] benzohydrazide (BNBC-n, n = 12, 14). However, BNBC-n showed synclinic monolayer smectic C (SmCs) features, suggesting that the hydroxyl groups in BNB-n have an important role in the formation of anticlinic molecular packing in the ...

We report on the self-assembly of a new two-component hydrogel of thymidine (T) and melamine (M) which formed supramolecular complex (≥ 0.1%, w/v) based on intermolecular hydrogen-bonding. The 3D morphologies were tuned by changing the molar ratio of T and M in aqueous medium from 3/1 to 1/3. The xerogels respectively showed rod, sheet and flower structures as observed under SEM. Fourier transform infrared (FT-IR) spectroscopy and wide angle X-ray scattering (WAXD) patterns confirmed that thymidine and melamine form supramolecular complexes through intermolecular hydrogen-bonding. The different structures of the complexes are proposed for the different compositions of the components.

In order to reduce the number of hydrogen bonds in biamide derivatives, one amide group in N-(4-cetyloxybenzoyl)-N'-(4'-nitrobenzoyl) hydrazine (C16-NO2) was replaced by a Schiff base group, forming N-(4-cetyloxybenzoyl)-N'-(4'-nitrobenzylidene) hydrazine (C16-Sch). Computational study on the molecular structure at B3LYP/6–311+G** level revealed that the molecular geometry of C16-NO2 could be well retained by C16-Sch. In addition, C16-Sch exhibited the same mesophase structure (SmA1) as C16-NO2, and the hydrogen bonding was demonstrated to be still interacting in the mesophase. However, compared to C16-NO2, the mesophase stability of C16-Sch is dramatically decreased by the reduction of the number of hydrogen bonds, providing direct evidence that intermolecular hydrogen bonding plays an important role in stabilising the smectic phase.

The mesomorphic dihydrazide derivatives N,N′-bis(4-n-alkyloxybenzoyl) hydrazine (Cn) showed stable liquid crystalline properties and strong gelation ability in organic solvents, and showed environmentally tuned self-assembled structures. On heating, Cn (n = 7, 12, 16) exhibit thermotropic cubic phase with Pn3m symmetry; while in the gel phase, molecules of Cn self-assembled into higher ordered monolayer structure, which is the fundamental of the fibrous aggregates observed by SEM. Intermolecular hydrogen bonding between the dihydrazide groups was demonstrated to be the major driving force for both gelation of organic solvents and stabilization of the liquid crystalline phase.

We studied hydrogen-bonding assemblies in a series of dumbbell-shaped hydrazine derivatives, namely oxalyl N',N'-bis(3,4-dialkoxybenzoyl)-hydrazide (BFH-n, n = 4, 6, 8, 10) and oxalyl N',N'-dibenzoyl-hydrazide (FH-0). It has been demonstrated that NH-1 protons of BFH-n precipitated from tetrahydrofuran (THF) or dimethylformamide (DMF) were involved in intramolecular H-bonding to form 6-membered rings. Meanwhile, NH-2 protons of BFH-n precipitated from THF formed intermolecular hydrogen bonds with C═O groups of neighboring molecules, while NH-2 protons of BFH-n precipitated from DMF formed intermolecular hydrogen bonds with C═O group of neighboring DMF molecules. C═O, -CH(3), and -CH groups of DMF molecules participated in multiple intermolecular hydrogen bonds with the -N-H and -C═O groups of FH-0 molecules in single-crystals formed in DMF, leading to a double helix morphology with a pitch of 24.2 Å along the c direction. Both left- and right-handed helical micrometer-length ribbons with nonuniform helical pitches were observed in an achiral BFH-10 xerogel precipitated from DMF.

Symmetrical four-chained (tetracatenar) di-hydrazine derivatives, namely oxalyl N',N'-bis(3,4-dialkoxybenzoyl)-hydrazide (BFH-n, n = 4, 6, 8, 10), were synthesised. Investigations on the liquid crystalline properties by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and polarising optical microscopy (POM) showed that the di-hydrazine derivatives exhibited columnar mesophases and the symmetry of the mesophase changes from rectangular to hexagonal on increasing the temperature. The rectangular columnar mesophases of BFH-n (n = 6, 8, 10) remained stable down to 10°C during cooling and the subsequent recrystallisation from the Colr phase of BFH-n (n = 6, 8, 10) was observed on the second heating runs. Furthermore, the average number of molecules packing in a column slice was estimated to be three, based on their X-ray diffraction results. Intermolecular hydrogen bonding between –C=O and −N−H groups in crystalline and liquid crystalline phases was confirmed.

A twin-tapered bi-1,3,4-oxadiazole derivative (BOXD-T8) showed a monomeric feature and intramolecular charge transition at concentrations lower than 10(-5) mol/L. BOXD-T8 molecules self-assembled to nanoparticles and further to helical nanofibers with blue fluorescence emission in DMSO, while nanoribbons resulted in an emission-enhanced gel in ethanol. The strong fluorescent emissions of BOXD-T8 in an isolated state in apolar solvents were attributed to the coplanar conformation of the rigid backbone and the strong fluorescent emissions of BOXD-T8 in the aggregation states were attributed to the coplanar conformation of the rigid backbone and J aggregation.

Context: Anexcess circulating uric acid level, even within the normal range, is always comorbid with metabolic syndrome (MS), several of its components, and nonalcoholic fatty liver disease (NAFLD), which was regarded as hepatic manifestation of MS; however, these associations remain controversial. Objective: This study aimed to quantitatively assess the relationship between the serum uric acid (SUA) levels and the MS/NAFLD risk. Design: We searched for related prospective cohort studies including SUA as an exposure and MS/NAFLD as a result in MEDLINE (PubMed) and EMBASE databases up to January 31, 2015 and July 28, 2015, respectively. Pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) were extracted. A random-effects model was used to evaluate dose-response relationships. Main Outcomes: On the basis of 11 studies (54 970 participants and 8719 MS cases), a combined RR of 1.72 (95% CI, 1.45-2.03; P < .0001) was observed for the highest SUA level category compared with the lowest SUA level category. Furthermore, based on nine studies (51 249 participants and 8265 MS cases), dose-response analysis suggested that each 1 mg/dL SUA increment was roughly linearly associated with the MS risk (RR, 1.30; 95% CI, 1.22-1.38; P < .0001). Beyond that, SUA level increased NAFLD risk (RR, 1.46; 95% CI, 1.31-1.63). Each 1 mg/dL SUA level increment led to 21% increase in the NAFLD risk. Conclusions: This meta-analysis suggests that higher SUA levels led to an increased risk of MS regardless of the study characteristics, and were consistent with a linear dose-response relationship. In addition, SUA was also a causal factor for the NAFLD risk. Refereed/Peer-reviewed

The existing analog reordering and folding technology has the following problems: it cause the attenuation of the ultrasonic signal, and it is difficult to achieve beam steering in color Doppler ultrasonic diagnostic instrument. This article proposes a design method to achieve digital reordering of dynamic focusing data. The digital reordering is composed of two parts, bit reordering which is implemented with multiplier and byte reordering using switch selection. The results show that it can meet the design requirements using fewer resources.

The compound N, N’-bis (4-n-alkylo-xybenzoyl) hydrazine (4D16), containing a dihydrazide unit in the rigid core, had been systematically investigated in view of their gelation behaviors, topological structures, and gelation formation processes. It has been demonstrated that 4D16 shows strong gelation ability in nonpolar solvents such as benzene and toluene. The xerogels consist of entangled ribbons with the width about 5 μm. According to X-ray diffraction (XRD), cubic structure is revealed in the benzene system, whereas layered structure is observed in toluene system. The morphological observations and kinetic studies by fluorescence spectroscopy as well as rheological study further reveal that self-assembly processes during gelation also differs. Radius fibers with a fractal dimension about 1.4 were observed in benzene system; whereas, less open fibrillar structures with fractal dimension approximately 1.1 were revealed for toluene system. The present results appear to represent that the molecular packing modes turn out to be solvent-dependent, which is due to unique dynamic processes.

The single nucleotide polymorphism (SNP) rs1465618 in THADA at 2p21 has been identified as being associated with prostate cancer (PCa) risk in Europeans; however, it is not clear whether the SNP is related to PCa risk in multiple populations. We investigated the association of rs1465618 in THADA with PCa in a Chinese population and carried out a meta-analysis in multiple populations, testing the relevance of this SNP for PCa risk.We genotyped the SNP using high resolution melting (HRM) analysis and assessed its association with PCa risk in a case-control study of 289 PCa patients and 288 controls in a Chinese population. A meta-analysis was carried out with 36,313 PCa patients and 36,485 controls to evaluate the association of rs1465618 with PCa risk in multiple populations.rs1465618 in THADA was significantly associated with PCa risk (p = 0.026; odds ratio (OR) 1.327, 95% confidence interval (CI) 1.035-1.700). Furthermore, the rs1465618 variant genotype was associated with PCa aggressiveness (p = 0.044; OR = 2.053, 95% CI = 1.015-6.602) in the Chinese population. The meta-analysis showed that rs1465618 was significantly associated with PCa risk in multiple populations (p = 1.0×10(-8); OR = 1.127, 95% CI = 1.085-1.171).Our results showed that rs1465618 in THADA may be a shared susceptibility variant for PCa in multiple populations. THADA gene polymorphisms may impact PCa susceptibility and progression.

A series of title compounds of type (I) are prepared and their mesomorphic behavior is studied.

To develop an HPLC method for simultaneous determination of rutin, hyperoside, quercetin and kaempferol in Malus prunifolia from Shanxi province in China.The separation was performed on a Hypersil C18 column (4.6 mm x 250 mm, 5 microm), using a gradient elution with methanol-water containing 0.2% phosphoric acid as the mobile phase. The flow rate was 1.0 mL x min(-1), the detection wavelength was 360 nm and the temperature of column was 25 degrees T.The linear ranges of rutin, hyperoside, quercetin and kaempferol were 1.87-46.67 mg x L(-1), 6.40-160.0 mg x L(-1), 3.33-83.33 mg x L(-1), 0.80-20.00 mg x L(-1), respectively. The average recoveries (n=6) of the four constituents were 99.2% (RSD 2.9%), 98.2% (RSD 1.9%), 97.4% (RSD 2.3%), 97.2% (RSD 1.3%), respectively.The method was simple, accurate and can be used to evaluate medicinal value of Malus prunifolia.

In this study, the unsymmetrical π-conjugated gelators, 2-(3,4-bis(alkoxy)phenyl)-5-(pyridine-4-yl)-1,3,4-oxadiazole [4-POXD-Bn (n = 4, 8, 12)], were synthesized and screened for gelation in various solvents. The tendencies of the critical gelation concentration (CGC) and the gel–sol phase transition temperatures (Tgel) of the 4-POXD-B8 gels, as well as the relationship between the end-chain length of gelator and gelation ability, indicated that the solvophobic effect has a critical role in gelation. For the specific gelator that we studied, we observed that the strength of the solvophobic force was related to the solvent properties. The solvent effect on gelation was studied quantitatively using the solvent polarity parameters: polar solubility parameter (δa), dielectric constant (e), and polarity parameter (ET(30)). The results revealed that the favorable δa domain and ET(30) domain for the gelation of 4-POXD-B8 was in the range of 8.1–12.6 (cal cm−3)1/2 and 43.3–55.7 kcal mol−1, respectively. Meanwhile, a decrease of δa and ET(30) in the solvents is unfavorable for gelation. Furthermore, the solvent effect on the microstructure of the gels was studied via scanning electron microscopy (SEM). The SEM images revealed that the gels from 4-POXD-B8 in DMSO and DMF were composed of helical ribbons, whereas those formed in other solvents consisted of flat ribbons.