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In order to solve the toxic and hazardous issues of the agents in the chemical reduction process of graphene oxide (GO), disodium guanosine 5′-monophosphate (GMP-2Na) was used as an ideal reducing agent for the synthesis of functionalized GO (FGO) for lipase immobilization. At the condition of low amount adsorption of GMP-2Na indicated by the N1s spectra of X-ray photoelectron spectroscopy (XPS), the C/O atomic ratio of the FGO increased from 2.09 to 3.12, indicating the reduction of GO. As the amount of GMP-2Na increased, the intensity of the characteristic peak of GO in the XRD pattern decreased, and the I D /I G peak intensity of Raman spectra increased during the functionalization process. It was found that when the concentration of GMP-2Na is 0.20 mg/mL, the degree of hydrophobicity of FGO is conducive to the formation of optimal conformation of lipase. After immobilization, the activity of the immobilized enzyme reaches twice the value of free enzyme. At the same time, the protein loading reaches to 600 mg/g. The immobilized enzyme showed enhanced durability since no obvious decrease was observed after incubation for 8 h at pH 6.0 and pH 7.0. After storage for 35 days, the activity of GO-G@ enzyme was 54.47% higher than that of free enzyme. GO reduced by GMP-2Na provides a possibility to obtain a highly efficient lipase immobilization carrier.

In this note, we propose a modulated free energy combination of the methods developed by P.-E. Jabin and Z. Wang [Inventiones (2018)] and by S. Serfaty [Proc. Int. Cong. Math. (2018) and references therein] to treat more general kernels in mean-field limit theory. This modulated free energy may be understood as introducing appropriate weights in the relative entropy developed by P.-E. Jabin and Z. Wang (in the spirit of what has been recently developed by D. Bresch and P.-E. Jabin [Ann. of Math. (2) (2018)]) to cancel the most singular terms involving the divergence of the flow. Our modulated free energy allows us to treat singular potentials that combine large smooth part, small attractive singular part, and large repulsive singular part. As an example, a full rigorous derivation (with quantitative estimates) of some chemotaxis models, such as the Patlak–Keller–Segel system in subcritical regimes, is obtained.

To achieve efficient one-step production of gluconic acid, cascade reactions of glucose oxidase (GOD) and catalase (CAT) have been advocated in the biocatalysis system. In this work, the methodology of co-immobilization of GOD and CAT was investigated in details for obtaining improved enzyme loading and activity. The maximum adsorption capability of GOD and CAT was 24.18 and 14.33 mg·g−1, respectively. The matching between dimensions of enzymes and hierarchical pore sizes of carriers are critical to the success of immobilization process. The simultaneous self-assembly on glutaraldehyde cross-linked mesoporous carriers exhibited favorable properties in comparison with sequential immobilization of GOD and CAT. The conversion of glucose under adequate air by co-localized GOD&CAT sustained the activity more than 90% after repeated utilization in the production of sodium gluconate and gluconic acid, suggesting that the co-immobilized GOD&CAT could be a promising catalyst for gluconate and gluconic acid production in some chemical and food industries.

Surface amine modification could not only improve the microenvironment near the active sites of enzyme, but also enhance the multi-point chemical crosslinking between the enzyme and carrier. The linear structured polymer of e-poly- l -lysine (EPL) is an ideal donor of amino with much more exposed on the surface for enzyme attachment. Analysis of the result of dynamic light scattering (DLS) and circular dichroism (CD) demonstrated the favorable electrostatic interactions and negligible impact on the conformation of enzymes, Glucose Oxidase and Catalase (GOx&CAT). Titration and dissociation curve together with Zeta-potential characterization revealed that enzymes (EPL@GOx&CAT) under the protection of EPL had more stable structure and better activity and stability in acidic reaction environment. Meanwhile, the activity recovery of immobilized EPL@GOx&CAT increased to 1.56 times higher than that of GOx&CAT, and the acid resistance was improved by 1.44 times with the optimum pH shifting to acidic by 0.50 unit. The substrate affinity was raised with the decrease of Km from 5.98 to 4.35 mg mL−1. Thus, the gluconic acid production in low pH system could be increased by pH-engineering of the enzyme microenvironment via conjugation with positively charged polyelectrolyte.

The continuous-wave 100 W-class 808 nm laser diode arrays with extremely high power conversion efficiency of 68% were reported at the heatsink temperature of 25 °C. To the best of our knowledge, this was the highest power conversion efficiency at continuous-wave 106 W 808 nm laser diode array with 50% fill factor so far. An asymmetric broad waveguide epitaxial structure with very low internal optical loss of 0.5 cm −1 was presented. In order to improve the efficiency, various fill factor devices were studied. The 50 W laser diode array with 30% fill factoir and 1.0 mm cavity length demonstrated power conversion efficiency of 71% at heatsink temperature of 15 °C.

Broad-area diode lasers with high output power and low lateral divergence angle are highly desired for extensive scientific and industrial applications. Here, we report on the epitaxial design for higher output power and a flared waveguide design for reduced divergence, which leads to high power operation with a low lateral divergence angle. A vertically asymmetric epitaxial structure was employed and optimized for low internal optical loss and high efficiency to realize high output power operation. Using a flared waveguide design, the lateral divergence angle was efficiently reduced by decreasing the number of high-order lateral optical modes significantly. The flared waveguide design introduces a smooth modification of the ridge width along the cavity without deteriorating laser performance. Based on the optimized epitaxial and waveguide design, we scaled the waveguide width to realize high continuous-wave power of 34.5 W at 25 °C. A low lateral divergence angle of 8° and high power conversion efficiency of 60% were achieved at the operating power level of 25 W. The life test data (30 A at 45 °C for 39 units, 0 failures in 1000 h) demonstrated reliable operation illustrating the efficient design for reduced lateral divergence angle and high operating power.

The report presents the high power mode-locking operation in an anomalous-dispersion fiber laser with a novel WS 2 saturable absorber (SA) based on fluorine mica (FM) substrate. Compared to organic host material such as polymer, FM has higher softening temperature, heat dissipation and laser damage threshold. By employing the SA, a stable mode-locked fiber laser is achieved. The duration of the pulse broadens from 2.816 ns to 3.654 ns almost linearly with increasing pump power. The average output power and single pulse energy can increase up to 33.5 mW and 4 nJ at the maximum pump power respectively. The results indicate that WS 2 /FM material is an ideal SA for high power Er-doped fiber (EDF) lasers.

Compared to the traditional chemical reduction method, a green and efficient strategy was successfully applied to regulate the surface heterogeneity of graphene oxide (GO). In this work, different kinds of amino acids were used to reduce and modify GO. The reduction and adsorption disparities of amino acids contributed to the difference of structural heterogeneity in terms of density, thermal tolerance and disorder of the oxygen-containing groups of GO. The modification also resulted in discrepancies in surface properties of the GO samples, such as hydrophobicity and surface charge. The functionalized GO was employed as a carrier for the immobilization of lipase from Thermomyces lanuginosus (lipase TL). The storage stability, the temperature and pH sensitivity of the immobilized biocatalysts and the free lipase TL were studied. Lipase immobilized on functionalized GO demonstrates superior enzymatic loading and relative activity compared to GO, with a maximum increase of 70% and 47%, respectively. The relative activity of lipase immobilized on functionalized GO was 19.21 times more than that of commercial immobilized lipase TLIM. Through molecular dynamics simulations we concluded that the increase in the relative activity of lipase TL is mainly related to its adsorption orientation and slight conformational change. Thus, our research offered a green and effective strategy to regulate the heterogeneity of nanomaterials for a suitable microenvironment to enhance the performance of immobilized lipase.

Summary Background Acute kidney injury (AKI) has become a worldwide public health problem, but little information is available about the disease burden in China. We aimed to evaluate the burden of AKI and assess the availability of diagnosis and treatment in China. Methods We launched a nationwide, cross-sectional survey of adult patients who were admitted to hospital in 2013 in academic or local hospitals from 22 provinces in mainland China. Patients with suspected AKI were screened out on the basis of changes in serum creatinine by the Laboratory Information System, and we reviewed medical records for 2 months (January and July) to confirm diagnoses. We assessed rates of AKI according to two identification criteria: the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) AKI definition and an increase or decrease in serum creatinine by 50% during hospital stay (expanded criteria). We estimated national rates with data from the 2013 report by the Chinese National Health and Family Planning Commission and National Bureau of Statistics. Findings Of 2 223 230 patients admitted to the 44 hospitals screened in 2013, 154 950 (7·0%) were suspected of having AKI by electronic screening, of whom 26 086 patients (from 374 286 total admissions) were reviewed with medical records to confirm the diagnosis of AKI. The detection rate of AKI was 0·99% (3687 of 374 286) by KDIGO criteria and 2·03% (7604 of 374 286) by expanded criteria, from which we estimate that 1·4–2·9 million people with AKI were admitted to hospital in China in 2013. The non-recognition rate of AKI was 74·2% (5608 of 7555 with available data). Renal referral was done in 21·4% (1625 of 7604) of the AKI cases, and renal replacement therapy was done in 59·3% (531 of 896) of those who had the indications. Delayed AKI recognition was an independent risk factor for in-hospital mortality, and renal referral was an independent protective factor for AKI under-recognition and mortality Interpretation AKI has become a huge medical burden in China, with substantial underdiagnosis and undertreatment. Nephrologists should take the responsibility for leading the battle against AKI. Funding National 985 Project of China, National Natural Science Foundation of China, Beijing Training Program for Talents, International Society of Nephrology Research Committee, and Bethune Fund Management Committee.

A 980 nm bottom-emitting vertical-cavity surface-emitting laser (VCSEL) array with a nonuniform linear arrangement is reported to realize high power with a Gaussian far-field distribution. This array is composed of five symmetrically-arranged elements of 200 μm, 150 μm, and 100 μm diameters, with the center spacing of 300 μm and 250 μm respectively. This structure makes it possible to discriminate against the higher order array supermodes. The theoretical simulation of the far-field distribution is in good agreement with the experimental result. An output power of 880 mW with a power density of 1 KW/cm2 is obtained. The divergence angle is below 20° in the range of operating current from 0 A to 4 A. The comparison between this nonuniform linear array and the conventional two-dimensional array is carried out to demonstrate the good performance of the linear array. A peak power of over 20 W is achieved under a short pulsed operation with a repetition frequency of 1 kHz.

Eight commercially harvested apple cultivars were analysed by gas chromatography and high-performance liquid chromatography, in particular the composition and level of sugars, organic acids, amino acids, phenolic compounds and fatty acids. The results showed great quantitative differences in the composition of the apple cultivars, particularly in their phenolic contents. Fructose was the most dominant sugar in the different apple cultivars, followed by glucose and sucrose, while malic acid was the principal organic acid. The C16:0, C18:0, C18:1, C18:2 and C18:3 fatty acids were the most abundant fatty acids, and the C18 family accounted for more than 70% of the total fatty acids content. Asparagine and serine were the principal amino acids. Chlorogenic acid and protocatechuic acid were the dominating phenolic compounds. The results provide important information on how to make the best use of the apple cultivars investigated, for both technological research and processing practice.

Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Wangfujing, Beijing 100730, China Department of Neurology, Huashan Hospital Affiliated to Fudan University, Shanghai, China Department of Neurology, Beijing Tiantan Hospital Affiliated to Capital MU, Beijing, China Department of Neurology, Ruijin Hospital affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China Department of Neurology, The Chinese PLA General Hospital, Beijing, China Department of Neurology, The Second Affiliated Hospital Zhejiang University College Of Medicine, Zhejiang Province, China Department of Neurology, The 2nd Affiliated Hospital of Soochow University, Jiangsu, China Department of Neurology, The 1st Affiliated Hospital of Xi’an Jiaotong Univ, Shanxi, China Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China GlaxoSmithKline (China) R&D Company Limited, Shanghai, China GlaxoSmithKline (China) Investment Co, Ltd, Shanghai, China