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Single‐atom catalysts (SACs) attract intensive attention owing to their unmatched catalytic activities and high atom utilization. Besides metal species themselves, the substrates play a key role for the improvement of their catalytic performance by optimizing metal–support interactions and coordination structures. In the past years, various 2D nanomaterials have been employed to anchor single metal atoms for renewable energy technologies and other important industrial processes. Tremendous progress has been achieved in the development of 2D supported SACs for advanced energy conversion reactions. This article provides a comprehensive and critical review of up‐to‐date advances in the field of 2D supported SACs. The state‐of‐the‐art characterizations including ex/in situ microscopic and spectroscopic techniques are summarized with the emphasis on their specific superiorities in identifying the reactive sites and reaction mechanisms, combined with theoretical calculations and experimental results. A brief overview of various reactions including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), two‐electron oxygen reduction reaction (2e‐ORR), carbon dioxide reduction (CO2RR), and nitrogen reduction reaction (NRR) under the framework of electrocatalysis and photocatalysis, is presented on basis of versatile 2D nanomaterial supports. Last, the key challenges and opportunities in this rising field are highlighted. [ABSTRACT FROM AUTHOR]

2D Bi2O2Se has recently attracted widespread research interest due to its high electron mobility and good air stability with tunable bandgap. However, the direct and controllable growth of large‐size, high‐quality ultrathin Bi2O2Se with tunable electronic properties remains a great challenge. Here, an organic ion template‐guided solution growth method, is developed using water as a solvent to efficiently obtain high‐quality 2D Bi2O2Se. Significantly, the thicknesses and morphologies of 2D Bi2OxSe with various oxygen deficiencies; are also achieved. Optical spectroscopic results indicate that oxygen defects can dramatically tune the electronic properties of Bi2O2Se, such as work function, band gap, and energy‐band positions. As a result, the optimized Bi2O2Se devices exhibit a high photoresponsivity of 842.91 A W−1, photo‐detectivity of 8.18 × 1012 Jones under 532 nm laser, and electron mobility of 334.7 cm2 V−1 s−1. This work proposes a new green solution method to synthesize large‐sized, high‐quality Bi2O2Se with tunable electronic structures that can be extended for various applications and provides a new possibility of transfer‐free large‐scale device manufacturing. [ABSTRACT FROM AUTHOR]

Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries. However, the low theoretical capacities, kinetics and stability of anode materials have limited their developments and commercializations. In this study, we propose a novel method to produce two‐dimensional layered bismuth oxide selenium (Bi2O2Se) and reduced graphene oxide (rGO) composites via a one‐step hydrothermal method. The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 mAh g−1 at a current density of 0.5 A g−1. The Bi2O2Se/rGO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04% after 5000 cycles. More importantly, the Bi2O2Se/rGO nanosheet composite is used as the anode electrode material with MnCo2O4.5@Ni(OH)2 as the cathode electrode material in aqueous alkaline battery. When the energy density is 76.16 W h kg−1, the power density reaches 308.65 W kg−1. At a power density of 10.21 kW kg−1, the energy density remains as high as 33.86 W h kg−1. The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials. [ABSTRACT FROM AUTHOR]

To meet the requirement of clean and efficient energy storage system for practical applications, supercapacitors (SCs), which are promising candidates for the next‐generation energy storage devices, have received tremendous attention. Herein, a hybrid electrode consisting of copper nanowires (Cu NWs) and carbon nanotubes (CNTs) is prepared by simple vacuum‐filtration method. Both Cu NWs and CNTs have excellent conductivities, high aspect ratios, and large surface areas, in which the two kinds of materials are evenly dispersed and are entangled with each other. The electrochemical performance characterization of the Cu@CuO NWs/CNTs hybrid electrode shows high specific capacitance of 1.7 F cm−2 and excellent cycling characteristics of 97.4% after 5000 cycles. The hybrid electrode of Cu@CuO NWs/CNTs with one‐dimensional (1D) structure provides significant advantages in terms of electron/ion transport pathways. The SC devices with excellent electrochemical performance and stability clearly demonstrate their broad applications as low‐cost, high‐performance power supplies for electronic devices. [ABSTRACT FROM AUTHOR]

New 2D bismuth oxychalcogenide nanosheets have excellent theoretical properties such as high electronic mobility and excellent oxidation resistance, which have good application prospective for optoelectronic devices. In this paper, during the synthesis process via mild hydrothermal route, ammonium bismuth citrate (C6H13BiN2O7·H2O) is selected as Bi source. Both Bi2O2S and Bi2O2Se nanosheets (lateral size: over 2.0 µm, thickness: ≈ 5.0 nm) are synthesized successfully using thiourea (CH4N2S) as S source, and sodium selenite (Na2O3Se) as Se source, respectively. The as‐synthesized Bi2O2S and Bi2O2Se materials have desirable nanosheet‐like morphologies. After adding C6H13BiN2O7·H2O, [(NH3)2C6H7O7]3‐ can intercalate between the interlayers of Bi2O2S or Bi2O2Se, limiting the growth along c‐axis direction, so that 2D sheets can be obtained. Finally, the photodetectors are fabricated based on Bi2O2S and Bi2O2Se films coated by thermal spraying. The experimental results show that the maximum responsivity and detectivity of Bi2O2S‐based photodetector are 0.059 A W‐1 and 6.77 × 109 Jones, respectively. As to Bi2O2Se‐based photodetector, the maximum responsivity and detectivity can reach 75.14 A W‐1 and 3.95 × 1012 Jones, respectively. The mild hydrothermal synthesis using ammonium bismuth citrate as Bi source is a universal and facile method to obtain Bi2O2S and Bi2O2Se nanosheets for optoelectronic applications. [ABSTRACT FROM AUTHOR]

An electrical method for junction temperature estimation of insulated-gate bipolar transistors (IGBTs) is presented in this study. Owing to the parasitic inductance between bond wire and main emitter terminal LE. The temperature-dependent falling collector current during turn-off transition would cause a negative voltage drop in the gate-main emitter voltage waveform vgE. Therefore, this negative voltage drop VgE-np is proportional to the junction temperature. A double-pulse test circuit is developed to verify the accuracy and feasibility of the proposed method. The impacts of collector-emitter voltage Vce, collector current Ic and bond-wires cut-off are also be discussed theoretically and experimentally. The experimental results show that the proposed VgE-np has a linear relationship with junction temperature as theoretical analysis and it is a bond-wires cut-off independent parameter in some special test point, which offers an effective way to estimate junction temperature without package destruction. The advantages of the proposed method include good linearity, bond-wires failure immunity and adequate sensitivity with junction temperature. [ABSTRACT FROM AUTHOR]

Study Type - Therapy (individual cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Gleason score is an important clinical characteristic for treatment decisions in patients with prostate cancer. Gleason score ≤6 are generally considered low-risk tumours with favourable clinical outcome. In this study we report long-term data on the actual recurrence risk and survival in patients with Gleason score ≤6 tumours. We were able to demonstrate that while recurrence rates are relatively low, 18% of patients experience PSA recurrence, and 6% experience overt clinical metastases at 15-year follow-up. OBJECTIVE • To determine the actual recurrence risk of patients with a Gleason score (GS) ≤6 treated with radical retropubic prostatectomy (RRP) and bilateral lymphadenectomy in a cohort with long-term follow-up. PATIENTS AND METHODS • The USC/Norris Comprehensive Cancer Center database included 3235 consecutive patients who underwent RRP for prostate cancer between January 1972 and December 2005. We identified 1383 patients with a GS ≤ 6 in prostatectomy specimens. Median follow-up was 8.3 years. Data on pathological and clinical characteristics and outcome were prospectively recorded. • Statistical analysis was performed using the stratified log-rank test and stepwise Cox regression analysis. RESULTS • A GS of 6 was present in 66%, 5 in 27%, 4 in 5% and 3 or 2 in 3% of cases. Tumour classification was pT2N0 (83%), pT3N0 (14%), pT4N0 (0.1%) and any TN1 (2%). • Positive margins were seen in 18%. Estimated PSA and clinical recurrence rate were 14% and 4% after 10 years and 18% and 6% after 15 years, respectively. In multivariate analysis, N-stage ( P < 0.001), T-stage ( P= 0.02) and margin status ( P < 0.001) were associated with PSA recurrence. • N-stage ( P < 0.001) and T-stage ( P= 0.01) were associated with clinical recurrence. • Overall, patients with a GS ≤ 6 accounted for 26% of all PSA recurrences and for 20% of all patients with clinical recurrences in the database. CONCLUSION • A relatively small proportion of patients with a GS ≤ 6 cancer developed PSA recurrence and/or overt metastasis. However, these patients account for a substantial minority of those who experienced recurrence and metastasis. [ABSTRACT FROM AUTHOR]

Degradations of reactive brilliant red X-3B solution by both conventional UV irradiation and microwave electrodeless UV irradiation were investigated. Degradation processes were studied by UV-VIS spectrophotometry, total organic carbon (TOC), high performance capillary electrophoresis (HPCE), conductivity, pH value, and ion chromatography. The results of color removal (%) and TOC removal (%) showed that the degradation by microwave electrodeless UV irradiation was more effective than by conventional UV irradiation. The results of UV-VIS absorption spectra and HPCE analyses indicated that the degradation of reactive brilliant red X-3B was occurred at the conjugation system first, the benzene ring and the naphthalene ring later. The reactive brilliant red X-3B was cleaved into some new small compounds and eventually most of the organic substances were mineralized to CO and HO. The results of the conductivity analysis suggested that the degradation has mainly occurred in the first 40 min of reaction. The pH value of reactive brilliant red X-3B solution was decreased first and then was increased. The results of inorganic anions analysis hinted that many of the N, Cl, and S elements from reactive brilliant red X-3B were still attached in organic molecules. Degradation processes were studied by UV-VIS spectrophotometry. The results indicate that the dye was cleaved into small compounds and that most of the organic substances were mineralized to CO and HO. [ABSTRACT FROM AUTHOR]

Recently, three independent laboratories reported the generation of induced pluripotent stem cells (iPSCs) from pig (Sus scrofa). This finding sums to the growing list of species (mouse, human, monkey, and rat, in this order) for which successful reprogramming using exogenous factors has been achieved, and multiple others are possibly forthcoming. But apart from demonstrating the universality of the network identified by Shinya Yamanaka, what makes the porcine model so special? On one side, pigs are an agricultural commodity and have an easy and affordable maintenance compared with nonhuman primates that normally need to be imported. On the other side, resemblance (for example, size of organs) of porcine and human physiology is striking and because pigs are a regular source of food the ethical concerns that still remain in monkeys are not applicable. Besides, the prolonged lifespan of pigs compared with other domestic species can allow exhaustive follow up of side effects after transplantation. Porcine iPSCs may thus fill the gap between the mouse model, which due to its ease is preferred for mechanistic studies, and the first clinical trials using iPSCs in humans. However, although these studies are relevant and have created significant interest they face analogous problems that we discuss herein together with potential new directions. © 2010 IUBMB IUBMB Life, 62(4): 277–282, 2010 [ABSTRACT FROM AUTHOR]

The effect of various additives such as TiB2, HfB2, CrB2, TaB, TaSi2, LaB6, La2O3, and AlN on the oxidation behavior of ZrB2-based ultra-high-temperature ceramics (UHTCs) at 1800°C was investigated. The additions of CrB2 and HfB2 to the ZrB2–SiC composites have minor effect on the structure evolution of the oxide scale and oxidation resistance. However, all the other additives, especially for Ti and Ta compounds, have changed the oxidation mechanism resulting in a marked detrimental effect on the oxidation resistance of ZrB2-based UHTCs. [ABSTRACT FROM AUTHOR]

Oxidation of ZrB2-based ultrahigh-temperature ceramic composites containing 10, 20, and 30 vol% SiC was performed at 1900°C for 1 h in air. ZrB2–20 vol% SiC exhibited the highest oxidation resistance at this temperature and formed a dense coherent oxide scale after oxidation, whereas a strong degradation was observed for both ZrB2–10 vol% SiC and ZrB2–30 vol% SiC. In addition, cracks and spallation in the oxide scale were also detected for the latter materials. The oxidation behaviors of ZrB2–SiC composites were investigated. The effect of SiC content was analyzed and oxidation models were proposed to describe the observed microstructures. [ABSTRACT FROM AUTHOR]

I investigate the information content of S&P 500 index changes by examining the price and volume reaction of the industry and size matched firms. Using a sample of S&P 500 additions between 1976-2001, I find a significantly positive price reaction, but no volume reaction, for the matching firms. In addition, the matching-firm price reaction is negatively related to the added firm's weight in its industry. These findings suggest that the index addition conveys favorable information about the added firm and its industry. [ABSTRACT FROM AUTHOR]

The distribution of pores and the mechanical properties of materials are the key factors in preparing satisfactory low‐k films. In the present study, a kind of silsesquioxane‐polyethylene glycol (SSQ‐PEG) was synthesized and used as a template to make the distribution of pores more even in the low‐k films. The crosslinking density of films could be adjusted by the sol‐gel of tetramethoxysilane/dimethoxydimethylsilane with various proportions. The porosity of films could also be adjusted with different proportions of pendant PEG chains introduced. A dielectric constant as low as 2.1 had been achieved for nanoporous polyorganosilicate films with good tenacity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1238–1243, 2007 [ABSTRACT FROM AUTHOR]

TiB2-Cu ceramic-metal composites were prepared by combustion synthesis of elemental titanium, boron, and copper ponders. The synthesized product consisted of two phases: TiB2 and copper. The addition of copper improved the strength and fracture toughness, thermal expansion coefficient, and thermal conductivity of TiB2. Thermal shock and ablation resistances of TiB2-Cu composites were studied using a plasma torch are heater. Monolithic TiB2 failed catastrophically when the plasma arc How reached the specimen surface. However, no cracks were found on the ablation surface of the TiB2-Cu ceramic-metal composites. The fractional mass loss was 4.09% for a TiB2- 40Cu composite, which was close to the traditional W/Cu alloys. Volatilization of metal binder and mechanical erosion of TiB2 were observed the be the major ablation mechanisms. An ablation process model is proposed for the TiB2-Cu composites. [ABSTRACT FROM AUTHOR]

A dipeptide, L-glutamyl L-tryptophan (L-glu-L-trp), was identified in a screen for immunomodulators in the soluble fraction of the thymus. L-glu-L-trp inhibits tumor growth in mice without showing direct cellular toxicity in a variety of human tumor cell lines. L-glu-L-trp antitumor activity in vivo requires the presence of natural killer (NK) cells. Defective trafficking of cytoplasmic granules caused by the Lyst mutation also resulted in loss of antitumor activity of the dipeptide. The effect of L-glu-L-trp on tumor growth in mice with targeted gene mutations demonstrated the absolute requirement for perforin for antitumor activity. The requirement of 2 major modulators of NK cell activity, gamma interferon (IFNγ) and interleukin (IL)-12, were also tested. L-glu-L-trp had full antitumor activity in IFNγ knockout mice, but had significantly diminished activity in IL-12 knockout mice. These data show that L-glu-L-trp antitumor activity in mice is dependent on cytolytic cell activity of NK or NKT cells. L-glu-L-trp in vivo regulates NK cell function independent of IFNγ but partly dependent on IL-12. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Poly(dimethylsiloxane) (PDMS) is commonly used as the negative friction layer of triboelectric nanogenerator (TENG) which can harvest ubiquitous mechanical energy. However, it is essential to improve the energy output of PDMS‐based TENGs with high visible transmittance for transparent flexible TENG. In this study, a simple, cost‐effective and efficient approach is demonstrated to modify PDMS without degrading high transparency. The novel flexible TENG based on PDMS‐PTFE composite film exhibits high output voltage and large transfer charge quantity of 95 V and 85 nC respectively, which are enhanced more than threefold in the output compared with pristine PDMS‐based TENG. And the TENG device generates average power output of 3.0 W m−2 across the matched optimal load resistance. The enhancement is attributed to PTFE particles dispersed in PDMS matrix, which can increase surface potential and reduce work function. Moreover, the TENG device also remains good transparency and flexibility, which satisfies the demands of transparent and flexible electronic devices. The proposed PDMS/PTFE based TENG shows good application prospects for various power sensors and even wearable energy suppliers. High‐performance transparent and flexible triboelectric nanogenerators (TENG) based on PDMS‐PTFE composite films are fabricated by a facile approach in this paper. The TENG exhibits admirable properties which have been attributed to PTFE particles dispersed in PDMS matrix. This work shows good application prospects for various power sensors and even wearable energy suppliers. [ABSTRACT FROM AUTHOR]

In the structure of the title compound, C14H24N2O2, the two benzene rings are linked by a 1,6-dioxyhexyl chain to form a centrosymmetric nonplanar structure, the dihedral angle between the two rings being 0.00 (9)°. The structure displays an intramolecular N—H...O hydrogen bond and the molecular packing is controlled by N—H...π and C—H...π interactions. [ABSTRACT FROM AUTHOR]