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Metal-organic frameworks (MOF) materials are promising materials for gas separation, but their application still faces various challenges. A strategy is now reported for introducing subunits of MOFs into traditional zeolite frameworks to obtain applicable adsorbents with advantages of both zeolites and MOFs. The subunits of ZIFs were introduced into zeolite Y and zeolite ZSM-5 for CH4 /N2 separation. Both the molecular simulation and experimental results validated that the IAST CH4 /N2 selectivity of the resulting samples greatly improved (above 8, at 100 kPa and 25 °C) with the incorporation of ZIF subunits into zeolites structure, and the selectivities were obviously higher than that of zeolites and even better than that of ZIFs. This strategy not only gave rise to an efficient adsorbent for CH4 /N2 separation but also provided ideas for design of other adsorption and separation materials.

Aim The growing number of patients suffering from chronic renal disease (CKD) is a challenge for the development of innovative therapies. Researchers have studied the therapeutic effects of cell therapy in acute kidney injury (AKI). However, the therapeutical effect of conditional medium (CM) in the CKD models have been rarely reported. Here, we examined the effects of umbilical cord derived-mesenchymal stem cells (hUC-MSCs) CM on renal fibrosis in a rat model of unilateral ureteral obstruction (UUO). Methods We randomly divided the animals into three groups: sham-operated, UUO, UUO + CM. CM was administered via the left renal artery after total ligation of the left ureter. Rats were killed after 14 days of obstruction. Histological changes and oxidative stress parameters were assessed. Western blotting and immunohistochemistry analysis were used to measure epithelial-mesenchymal transition (EMT) markers, including epithelial cadherin (E-cadherin), α-smooth muscle actin (α-SMA), tumor necrosis factor-α (TNF-α), Collagen-I, and transforming growth factor β1 (TGF-β1). Proliferation and apoptosis of renal tubular epithelial cells (RTEs) were also measured. Results HucMSC-CM significantly reduced the levels of malondialdehyde (MDA) and reactive oxygen species (ROS), and increased the activity of glutathione (GSH) induced by UUO. Moreover, CM significantly reduced the expression of TGF-β1, α-SMA, TNF-α and Collagen-I in UUO kidney, promoted the proliferation of RTEs and inhibited its apoptosis. In addition, the increased expression of E-cadherin also reflects the effective improvement of renal interstitial fibrosis. Conclusion This study shows that CM protects UUO-induced kidney damage and therefore could be a potential tool to prevent CKD progression.

AIM Although human chorionic gonadotropin (hCG) has long been employed in the management of cryptorchidism, its safety and efficacy is still controversial. Hence, in the present study, we conducted a meta-analysis of the treatment of cryptorchidism using hCG. METHODS We searched the Medline, Embase, CINAHL, EBSCO, The Cochrane Library, China National Knowledge Infrastructure and WanFang databases. Data were extracted by two reviewers using the designed extraction form. Data up to July 2015 were obtained using the terms 'cryptorchidism', 'chorionic gonadotropin' and 'randomised controlled trials'. All the publications were downloaded, and the respective authors were contacted for any further details and clarifications, if deemed necessary. The data analysis included randomised controlled trials that compared hCG with other hormone treatments offered to prepubescent males presenting with cryptorchidism. Testicular descent rate was used as the final positive outcome of the treatments offered. The software Review Manager (RevMan 5.3, The Cochrane Collaboration, London, UK) was used to review the management and data analysis. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled with a fixed effect model if no heterogeneity was present. RESULTS A total of seven trials satisfied the selection criteria. The overall quality of the studies downloaded from various databases was low. Data from these seven studies were divided into three subgroups depending on the design of the trials: Two studies compared hCG with a placebo, and three studies compared hCG with gonadotropin-releasing hormone (GnRH) in unilateral cryptorchidism, whereas two other studies compared hCG with GnRH in bilateral cryptorchidism. Analysis of these trials revealed no significant differences between the effectiveness of hCG treatment and GnRH treatment in bilateral (RR 0.05, 95% CI (-0.29-0.40), two trials, n = 104, P = 0.76) as well as unilateral cryptorchidism (RR 0.04, 95% CI (-0.12, 0.21), three trials, n = 81, P = 0.61). A meta-analysis of these studies showed that hCG treatment is not superior to placebo (RR 7.74, 95% CI (0.14-425.72), two trials, n = 31, P = 0.32). CONCLUSION A meta-analysis of the seven studies led us to conclude that hCG treatment is no more effective than placebo, and there were no significant differences in the effectiveness of hCG versus GnRH treatment.

Atomically thin bismuth oxyselenide (Bi2 O2 Se) exhibits attractive properties for electronic and optoelectronic applications, such as high charge-carrier mobility and good air stability. Recently, the development of Bi2 O2 Se-based heterostructures have attracted enormous interests with promising prospects for diverse device applications. Although the electrical properties of Bi2 O2 Se-based heterostructures have been widely studied, the interlayer charge transfer in these heterostructures remains elusive, despite its importance in harnessing their emergent functionalities. Here, a comprehensive experimental investigation on the interlayer charge transfer properties of two heterostructures formed by Bi2 O2 Se and representative transition metal dichalcogenides (namely, WS2 /Bi2 O2 Se and MoS2 /Bi2 O2 Se) is reported. Kelvin probe force microscopy is used to measure the work functions of the samples, which are further employed to establish type-II band alignment of both heterostructures. Photoluminescence quenching is observed in each heterostructure, suggesting high charge transfer efficiency. Time-resolved and layer-selective pump-probe measurements further prove the ultrafast interlayer charge transfer processes and formation of long-lived interlayer excitons. These results establish the feasibility of integrating 2D Bi2 O2 Se with other 2D semiconductors to fabricate heterostructures with novel charge transfer properties and provide insight for understanding the performance of optoelectronic devices based on such 2D heterostructures.

A by-product provided by the producer of 2-methyl-3-furanthiol was characterized by 1D and 2D NMR, GC–MS (EI) and HRMS analyses. It was identified to be 4-(5-methyl-2-furylthio)-5-methyltetrahydrofuran-2-thione and its precursor 2-methyl-5-thioacetylfuran was also determined. 2-Methyl-5-thioacetylfuran was formed by the nucleophilic addition of AcSH to the aldehyde group of 4-oxo-2-pentenal during the industrial production of 2-methyl-3-furanthiol. The hydrolysis of 2-methyl-5-thioacetylfuran under basic conditions gave 5-methyl-2-furanthiol, which underwent autothiylation to lead to the formation of 4-(5-methyl-2-furylthio)-5-methyltetrahydrofuran-2-thione.

In this study, core-shell structured Li3V2(PO4)3/C wrapped in graphene nanosheets has been successfully prepared. The reduction of graphene oxide and the synthesis of Li3V2(PO4)3/C are carried out simultaneously using a chemical route followed by a solid-state reaction. The effects of conducting graphene are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectra and electrochemical measurements. The results reveal that the graphene sheets not only form a compact and uniform coating layer throughout the Li3V2(PO4)3/C, but also stretch out and cross-link into a conducting network around the Li3V2(PO4)3/C particles. Thus, the graphene decorated Li3V2(PO4)3/C electrode exhibits superior high-rate capability and long-cycle stability. It delivers a reversible discharge capacity of 178.2 mAh·g−1 after 60 cycles at a current density of 0.1 C, and the rate performances of 176, 169.3, 156.1 and 135.7 mAh·g−1 at 1, 2, 5 and 10 C, respectively. The superior electrochemical properties make the graphene decorated Li3V2(PO4)3/C composite a promising cathode material for high-performance lithium-ion battery.

What's known on the subject? and What does the study add? Surgical correction of the congenital completely buried penis (CCBP) is a difficult challenge and there is no unanimous consensus about the surgical ‘gold standard’ and patient eligibility for surgery. In the present study, dysgenetic fundiform ligaments were found to be attached to the distal or middle shaft of the penis. This abnormality can be successfully corrected by releasing the fundiform ligament and mobilising the scrotal skin to cover the length of the penile shaft. The study shows that the paucity and traction of the penile skin and an abnormal fundiform ligament are important anatomical defects in CCBP. Dorsal curve and severe shortage of penile skin in erectile conditions are the main indications for surgical correction. Objective To present our experience of anatomical findings for congenital completely buried penis (CCBP), which has no unanimous consensus regarding the ‘gold standard’ for surgical correction and patient eligibility, by providing our surgical technique and illustrations. Patients and Methods Between February 2006 and February 2011, 22 children with a median (range) age of 4.2 (2.5–5.8) years, with CCBP underwent surgical correction by one surgeon. Toilet training and photographs of morning erections by parents were advised before surgery. The abnormal anatomical structure of buried penis during the operation was observed. The technique consisted of the release of the fundiform ligament, fixation of the subcutaneous penile skin at the base of the degloved penis, penoscrotal Z-plasty and mobilisation of the penile and scrotal skin to cover the penile shaft. Results In reflex erectile conditions, CCBP presents varying degrees of dorsal curve and shortage of penile skin. Dysgenetic fundiform ligaments were found to be attached to the distal or middle shaft of the penis in all patients. All wounds healed well and the cosmetic outcome was good at 6-month follow-up after the repair. Conclusion The appearance of the dorsal curve in CCBP mainly results from the traction of penile dorsal skin and the abnormal attachment of the fundiform ligament to the shaft. This abnormality can be successfully corrected by releasing the abnormal fundiform ligament and mobilising scrotal skin to cover the length of the penile shaft.

ZnO is an important wide bandgap compound semiconducting material and exhibits a wide range of novel structures that can be grown by tuning the growth rates along its fast growth directions. Highly ordered macroporous materials by using colloidal crystal template method are of great interest in many fields including photonic crystals and catalysts. In this study, ZnO with highly ordered porous structure was deposited by different electrochemical method. Nanomeshes, inverse opal structures, and spherical/ellipsoidal particles with pore arrays are fabricated by the colloidal crystals with different functional groups. The template effects on the morphology of the macroporous structures for different surface groups are studied. All the nanomeshes grows along the {111} plane family by colloidal crystals without functional groups. Disordered arrangements of the nanomeshes are induced by colloidal crystals with hydroxyl groups. The inverse opal structures fabricated by template with carboxyl groups are smoother in surface.

We present the fabrication and performance studies of organic photovoltaic (OPV) devices with bulk heterojunction (BHJ) structure that use organic solution-processable functionalized graphene (SPFGraphene) as an electron-acceptor material and poly(3-octylthiophene) (P3OT) as a donor material. The structural configuration of the device is ITO/PEDOT:PSS/P3OT:PCBM–SPFGraphene/LiF/Al. After mixing graphene into the device, the performance enhanced significantly. Given illumination at 100 mW/cm2 AM1.5 and P3OT/PCBM (1:1) mixture with 9 wt% of SPFGraphene, we recorded the best performances. The open-circuit voltage (Voc) is 0.67 V. The short-circuit current density (Jsc) is 4.6 mA/cm2. The FF is 0.37. And the power conversion efficiency is 1.14%. In the P3OT:PCBM–SPFGraphene composite, the SPFGraphene acts as exciton dissociation sites and provides the transport pathway of LUMO–graphene–Al. Adding SPFGraphene into P3OT produces an appropriate energetic distance between the HOMO and the LUMO of the donor/acceptor, which leads to a high open-circuit voltage. Besides, doping SPFGraphene provides a higher exciton dissociation volume mobility of carrier transport, which leads to a large short-circuit current density.

ansa-Tetramethyldisiloxane-bridged indenyl, tetrahydroindenyl and cyclopentadienyl zirconium complexes 1-4 were prepared. The pure rac-1-3 and meso-1-2 complexes were separated by fractional crystallization. Indenyl complexes, both rac-1 and meso-1, in the presence of methylaluminoxane (MAO), have very high activities for ethylene polymerization. The molecular weight of polyethylene produced with rac-1 is extremely high and significantly dependent on polymerization temperature. The tern-butyl-substituted cyclopentadienyl complex exhibits low activity and produces polyethylene of low molecular weight.

Ethylene, propylene, and ethylidene norbornene (D) were terpolymerized by Et [Ind]2ZrCl2/MAO in solution and supported on silica. The presence of D decreases the rate of polymerization. EPDM containing between 3 and 22 wt % of D were synthesized which have narrow MW distribution. The supported catalyst produces EPDM with E/P ratio which are similar to the ratio in the feed.