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• Influence of 60Co gamma-ray irradiation on the Er:LuYSGG crystal was demonstrated. • Maximum average output power of 886 mW is achieved after irradiation. • Maximum output power and slope efficiency are reduced by only 2.5% and 3.7%. • Lifetime ratio between lower and upper laser levels is reduced after irradiation. • Er:LuYSGG crystal is a potential 2.79 μm radiation-resistant laser material. We demonstrate the influence of gamma-ray irradiation on the structure, spectroscopies, and laser performance of Er:LuYSGG crystal. After 100 Mrad 60Co gamma-ray irradiation, the crystal structure remains unchanged, the absorption near 968 nm and emission within 2.7 ∼ 3 μm are almost unaffected, the level lifetimes are reduced, and the maximum output power of 886 mW is achieved with a maximum slope efficiency of 20.8%. The maximum output power and slope efficiency decrease by only 2.5% and 3.7% after irradiation, respectively, and the M 2 factor is little affected by irradiation. The results indicate that the Er:LuYSGG crystal is a potential mid-infrared radiation-resistant laser material applied in radiation environments. [ABSTRACT FROM AUTHOR]

Structure, defects, and spectroscopic properties of a Yb,Ho,Pr:YAlO 3 (Yb,Ho,Pr:YAP) single crystal grown by the Czochralski method were investigated. The effective segregation coefficients of the Yb 3+ , Ho 3+ , and Pr 3+ ions are 1.06, 1.32, and 0.90 in YAP host, respectively. The structural parameters are obtained by the X-ray Rietveld refinement method. A high crystalline quality of the Yb,Ho,Pr:YAP is determined by the X-ray rocking curve. The dislocations of (100), (010), and (001) faces are studied using the chemical etching with the phosphoric acid etchant. The absorption spectra show that there exists strong absorption in the wavelength range of 900–1000 nm, and the fluorescence spectrum excited by 970 nm LD presents that the strongest emission is located at 2853 nm, indicating the Yb 3+ ions can be acted as the sensitizer for the Ho 3+ ions. The level lifetimes indicate that the Pr 3+ ions can play a deactivator role for the Ho 3+ ions. All these results imply that the Yb,Ho,Pr:YAP crystal can be regarded as a promising candidate for realizing 2.8–3.1 μm laser output. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) transfers heat to storage media during the charging period, and releases it at a later stage during the discharging step. It can be usefully applied in solar plants, or in industrial processes, such as metallurgical transformations. Sensible, latent and thermo-chemical media store heat in materials which change temperature, phase or chemical composition, respectively. Sensible heat storage is well-documented. Latent heat storage, using phase change materials (PCMs), mainly using liquid–solid transition to store latent heat, allows a more compact, efficient and therefore economical system to operate. Thermo-chemical heat storage (TCS) is still at an early stage of laboratory and pilot research despite its attractive application for long term energy storage. The present review will assess previous research, while also adding novel treatments of the subject. TES systems are of growing importance within the energy awareness: TES can reduce the LCOE (levelized cost of electricity) of renewable energy processes, with the temperature of the storage medium being the most important parameter. Sensible heat storage is well-documented in literature and applied at large scale, hence limited in the content of the present review paper. Latent heat storage using PCMs is dealt with, specifically towards high temperature applications, where inorganic substances offer a high potential. Finally, the use of energy storage through reversible chemical reactions (thermo-chemical storage, TCS) is assessed. Since PCM and TCS storage media need to be contained in a capsule (sphere, tube, sandwich plates) of appropriate materials, potential containment materials are examined. A heat transfer fluid (HTF) is required to convey the heat from capture, to storage and ultimate re-use. Particle suspensions offer a valid alternative to common HTF, and a preliminary assessment confirms the advantages of the upflow bubbling fluidized bed and demonstrates that particulate suspensions enable major savings in investment and operating costs. Novel treatments of the TES subject in the review involve the required encapsulation of the latent and chemical storage media, the novel development of powder circulation loops as heat transfer media, the conductivity enhancement of PCMs, the use of lithium salts, among others. [ABSTRACT FROM AUTHOR]

A novel application of powders relies on their use as heat transfer medium for heat capture, conveying and storage. The use of powders as heat transfer fluid in concentrated solar systems is discussed with respect to current technologies. The specific application reported upon is the use of powder loops in Solar Power Tower plants. In the proposed receiver technology, SiC powder is conveyed as a dense particle suspension through a multi-tube solar receiver in a bubbling fluidization mode, the upwards flow being established by pressurizing the powder feed. Tests were conducted with a single-tube receiver unit at the 1 MW solar furnace of CNRS (Odeillo Font-Romeu, F). The measured wall-to-suspension heat transfer coefficient is a function of operating temperature, applied air velocity and imposed solid circulation flux: values increased with increasing solids flux from ∼430 to 1120 W/m 2 K. Empirical approaches and a heat transfer model were applied to compare experimental and predicted values of the heat transfer coefficient, with a fair agreement obtained. The research moreover provides initial data concerning the overall economy of the system. The high temperature of the circulating powder leads to an increased power cycle efficiency, an increased storage density, reduced thermal power requirements, reduced heliostat field size, reduced parasitic power consumption and increased plant capacity factor. [ABSTRACT FROM AUTHOR]

New developments of fluidized beds are focusing on their use in powder circulation systems for thermal energy capture, storage and re-use. Although fast particle motion and associated high degree of mixing favor the high rate of heat transfer in fluidized beds, they however cause inter-particle collision and bed-to-wall impacts, both leading to particle attrition. Experimental work on attrition was carried out in batch gas fluidized beds of 6.62 cm and 10 cm I.D. The rate of attrition was determined both for bubbling fluidized bed conditions, and when adding jet-orifices above the distributor. The attrition was determined from the variation in composition of bed material and collected carryover. A literature survey determined the dominant fluidization parameters, including operating superficial gas velocity, orifice velocity and size, bed weight and diameter, and particle characteristics. Analysis of the experimental findings resulted in a correlation that encompasses all relevant operating characteristics. As a result, the attrition rate can be correlated as the sum of the bubble-induced and jet-induced contribution: R t = K 1 γ U − U m f ⋅ W D + K 2 n or ⋅ d or 2 ⋅ U or 2 with K 1 and K 2 , the intrinsic attrition rate constants, being mainly a function of particle characteristics. K 1 is ~ 10 − 5 for soft, ~ 10 − 6 for hard and ~ 10 − 7 for very hard particles, respectively. K 2 is ~ 10 − 5 for silica sand. In general, attrition is negligible at low superficial gas velocities, but significantly increases through the jet-induced contribution if the orifice velocity exceeds ~ 30 m/s. [ABSTRACT FROM AUTHOR]

With the rapid development of network, the peer-to-peer (P2P) traffic has become one of the most important traffics on the Internet; meanwhile, it also brings many security problems to the network management. Thus, nowadays, P2P traffic identification is the hottest topic of P2P traffic management. Much effort has been made on this topic, however, effectiveness remains an issue and the classification performance needs to be further improved. Support vector machine (SVM) has advantages with resolving small samples and high dimension for P2P classification problems. However, the performance of SVM is largely dependent on its kernel and parameters. The traditional kernels are hard to map complicated function with high precision and the traditional parameters tuning methods are of low efficiency and difficult to obtain good parameters. As wavelet kernel function is able to approximate a function with high precision and Particle Swarm Optimization algorithm could tune the optimal parameters for SVM. Hence, in the paper, a novel SVM method based on wavelet kernel and particle swarm optimization algorithm (PSO) is proposed for P2P identification. First, the proposed approach tunes the best parameters for SVM with PSO on training data. Subsequently, the wavelet SVM configured with the best parameters is conducted to identify P2P traffic. Experimental results on campus traffic traces indicate that the proposed method is able to identify popular P2P applications with very high accuracy. [ABSTRACT FROM AUTHOR]

Lu 2.4 Y 0.6 Al 5 O 12 (LuYAG) crystals with three different doping concentrations of Tm 3+ and Ho 3+ were grown successfully by the Czochralski method. The crystals exhibit broad absorption band at 783 nm and the full width at half maximum (FWHM) are about 11 nm. Excited by 783 nm laser diode (LD), strong fluorescence peaks are observed near 2.9 μm, suggesting that the Tm 3+ ions can act as the sensitizer for Ho 3+ ions. The stimulated emission cross-sections at 2.911 μm are calculated to be 5.49 × 10 −18 cm 2 , 3.11 × 10 −18 cm 2 , and 4.04 × 10 −18 cm 2 , respectively. Compared with the Tm,Ho:LuAG, and Tm,Ho:YAG crystals, the Tm,Ho:LuYAG crystal with 3 at.% Tm 3+ and 1 at.% Ho 3+ has a relatively longer lifetime 0.138 ms for the upper level 5 I 6 and a shorter lifetime 7.25 ms for the lower level 5 I 7 , which is advantageous to the population inversion. These results indicate that the Tm,Ho:LuYAG crystal with 3 at.% Tm 3+ and 1 at.% Ho 3+ is a new potential candidate for realizing the 2.911 μm laser output. [ABSTRACT FROM AUTHOR]

A novel Yb,Ho,Pr:LuYAG laser crystal was successfully grown and investigated in detail, which belongs to the cubic system with a space group of I a-3d. The X-ray rocking curve of the as-grown crystal implied high crystalline quality. The dislocation defects were revealed by the chemical method. Moreover, the density, thermal expansion coefficient and thermal conductivity were determined. The absorption coefficient at 935 nm and the emission cross-section at 2.911 μm were obtained to be about 15.18 cm−1 and 2.23 × 10−21 cm2, respectively. The lifetime of the lower laser level 5I 7 was shown to decrease from 7.58 to 5.88 ms, while that of the upper laser level 5I 6 basically remained unchanged, suggesting that the co-doped Pr3+ possessed an efficient deactivation effect and was beneficial in attaining population inversions of Ho3+. The corresponding findings illustrate that the Yb,Ho,Pr:LuYAG crystal can serve as a novel promising gain medium for realizing the 2.911 μm laser pumped by ~ 940 nm high-power InGaAs laser diode. • A novel Yb,Ho,Pr:LuYAG laser crystal was successfully grown by Czochralski method. • The crystal possesses a high thermal conductivity, which is helpful in dissipating heat during laser action. • Yb3+ makes the crystal suitable for 935 nm LD pumping and Pr3+ can inhibit self-termination phenomenon. • High absorption coefficient at 935 nm and large emission cross-section at 2911 nm are beneficial in realizing ∼2.9 μm laser. • The Yb,Ho,Pr:LuYAG crystal is a new promising gain medium for realizing 2.911 μm laser. [ABSTRACT FROM AUTHOR]

Background. Differentiation among types of muscular dystrophy (MD) has remained challenging. In this retrospective study, we sought to develop a methodology for differentiation of MD types using analysis of serum enzyme profiles. Methods. The serum levels of enzymes from 232 patients, including 120 with DMD, 36 with BMD, 36 with FSHD, 46 with LGMD, and 11 with EDMD, were evaluated. Results. The characteristic profiles of serum enzymes facilitated differentiation of these five types of MD. DMD was characterized by simultaneous elevation of ALT, AST, LDH, and ALP; BMD and LGMD were characterized by elevation of ALT, AST, and LDH; and FSHD and EDMD were characterized by a lack of abnormal serum enzyme levels. We further developed discriminant functions to distinguish BMD and LGMD. For LGMD, LGMD2B patients had significantly higher ALP levels than non-LGMD2B patients (98±59 U/L versus 45±9 U/L, resp., p<0.05). Conclusions. Our approach enabled the determination of MD subtypes using serum enzyme profiles prior to genetic testing, which will increase the chance a mutation will be found in the first gene analyzed. [ABSTRACT FROM AUTHOR]

Cocrystallization can improve physical and chemical properties of active pharmaceutical ingredient, and this feature has great potential in pharmaceutical development. In this study, the cocrystal of piracetam and 3-hydroxybenzoic acid under grinding condition has been characterized by Raman and terahertz spectroscopical techniques. The major vibrational modes of individual starting components and cocrystal are obtained and assigned. Spectral results show that the vibrational modes of the cocrystal are different from those of the corresponding parent materials. The dynamic process of such pharmaceutical cocrystal formation has also been monitored directly with Raman and THz spectra. The formation rate is pretty fast in first several 20 min grinding time, and then it becomes slow. After ∼35 min, such process has been almost completed. These results offer us the unique means and benchmark for characterizing the cocrystal conformation from molecule-level and also provide us rich information about the reaction dynamic during cocrystal formation process in pharmaceutical fields. [ABSTRACT FROM AUTHOR]

Background. To improve assessment of dystrophinopathy, the aim of this study was to identify whether serum creatinine (Crn) level reflects disease severity. Methods. Biochemical, Vignos score, and genetic data were collected on 212 boys with dystrophinopathy. Results. Serum Crn level had a strong inverse correlation with Vignos score by simple correlation (r=-0.793) and partial correlation analysis after adjustment for age, height, and weight (r=-0.791; both P<0.01). Serum Crn level was significantly higher in patients with in-frame than out-of-frame mutations (Z=-4.716, P<0.01) and in Becker muscular dystrophy (BMD) patients than Duchenne muscular dystrophy (DMD) patients at ages 4, 5, 7, and 9 yr (all P<0.0125). After adjusting for age, height, and weight, BMD patients still had a significantly higher serum Crn level than DMD patients (β=7.140, t=6.277, P<0.01). Conclusions. Serum Crn level reflected disease severity and may serve as a supplemental index to distinguish DMD from BMD in clinical practice. [ABSTRACT FROM AUTHOR]

Aspergillus flavus produces potent mutagenic and carcinogenic polyketidederived secondary metabolites known as aflatoxins. Development of host plant resistance in peanut and other crops is the most environmentally friendly and cost-effective method to eliminate the serious problem of aflatoxin contamination in grains. To confirm that putative peanut genes identified in a previous microarray study were involved in peanut resistance to A. flavus infection, 14 genes were selected for further investigation through real-time PCR. The results revealed diverse patterns of gene expression during seed germination after A. flavus inoculation. Based on the expression levels and the relative-expression patterns over a 7-day period, the 14 host genes could be classified into six different groups belonging to three main biochemical and genetic defence processes of lipid metabolism, oxidative signalling and cell-wall synthesis during counterattack. A network of gene expression patterns was activated in sequential order in response to A. flavus invasion in both resistant and susceptible peanut lines during seed germination. Understanding gene expression patterns in peanut will be useful to breeders and other scientists interested in incorporating genetic resources of resistance against A. flavus into peanut germplasm and/or commercial cultivars via conventional and/or molecular methods. [ABSTRACT FROM AUTHOR]

Vibrational spectra of hydrated and anhydrous lamivudines, and also the dynamic process of polymorphic transformation have been characterized by Fourier transform infrared (FT-IR) and Raman spectroscopic techniques. The vibrational modes of both polymorphic lamivudines are assigned. FT-IR and Raman spectral results show that the interaction between crystalline water and lamivudine molecular has an important effect on the molecular vibration motions of polymorphic lamivudines. The two characteristic Raman peaks at 783 and 798 cm −1 represent hydrated and anhydrous lamivudine respectively. The relationship between changes of two characteristic peak normalized areas and heating time could be fitted with single exponential functions, and the dynamic information of polymorphic transformation of lamivudine drug is obtained. The decay rate of characteristic peak for hydrated lamivudine and the growth rate of that for anhydrous lamivudine are consistent during dehydration transformation process. The reported results provide us important benchmark for qualitatively monitoring different polymorphic drugs and also establishing the corresponding model for the polymorphic transformation of drugs in related pharmaceutical research fields. [ABSTRACT FROM AUTHOR]

Yb,Ho:YAP and Yb,Ho,Pr:YAP laser crystals with high optical quality are successfully grown using the Czochralski method. The absorption coefficient and band width of the two crystals at 970 nm are increased because of the doping of Yb 3+ sensitizer. The three strongest fluorescence peaks of the two crystals are located at approximately 2844, 2853, and 2912 nm, which correspond to the 5 I 6 → 5 I 7 level transitions of Ho 3+ ions. Lifetime measurements indicate that the deactivator Pr 3+ ions can efficiently decrease the lifetime of the lower level 5 I 7 from 8.848 ms to 1.258 ms. Energy-transfer mechanisms are also studied and analyzed, and up-conversion luminescence spectra provide the further evidence that Pr 3+ ions can efficiently depopulate Ho 3+ ions at the 5 I 7 level. All these results show that Yb,Ho,Pr:YAP crystal may be a promising laser medium for realizing 2.8–3.1 μm lasers pumped using a 970 nm laser diode. [ABSTRACT FROM AUTHOR]

The rapid development of mobile broadband services with continuously increasing traffic volumes has resulted in a number of challenges, including ubiquitous network coverage, high bandwidth, and reliable services for reasonable price, etc. To address these challenges, evolved packet system (EPS) is proposed as the evolution of the packet core network. While resource management and load balancing issues in EPS are discussed in 3GPP standardization, relatively few research works consider mechanism design for load information monitoring and evaluation. Furthermore, even though some load balancing algorithms have been proposed for integrated networks, the load balancing scheme design which achieves the optimization of joint system performance has not been extensively studied. In this paper, an inter-access system anchor based load balancing mechanism is introduced which performs load monitoring and evaluation for access gateways and networks, and an optimal load balancing algorithm is proposed for heterogeneous integrated networks. To characterize the performance of integrated networks, the concept of utility function is introduced and the comprehensive performance of integrated networks which support both single type service and multimedia service is modeled mathematically. Applying vertical handoff as an efficient mechanism for achieving load balancing, the optimal number of handoff users is obtained through solving the optimization problem. Numerical results demonstrate that load balancing between access networks can be achieved, and the optimal number of handoff users corresponding to the maximal joint network utility can be obtained. [ABSTRACT FROM AUTHOR]

Ambient pressure hydro-deoxygenation (HDO) of the phenolic-rich pyrolysis liquid fraction is a complex task due to the presence multiple phenolic compounds and light oxygenates. The phenolic-rich fraction differs from the overall pyrolysis liquid, known to be prone to re-polymerization and coking in the reactor or of the catalyst. In the present research, hydro-deoxygenation of oxygen-containing compounds in the phenolic fraction over Mo-based catalysts was carried out for the first time. It was found that Mo-based catalysts can successfully upgrade the phenolics into aromatics, the conversion rate was nearly 100%. The small amount of light oxygenates in the phenolic-rich fraction had no obvious effect on the hydro-deoxygenation reaction, the phenolic conversion was more than 95%. After assessing the performance for a representative phenolic model compound, the reaction was also successfully carried out on the phenolic fraction of the real pyrolysis liquid. It can be concluded that the catalysts can also be used for the HDO of the real pyrolysis liquid fraction at atmospheric pressure. • A phenolic-rich fraction was solvent-extracted from a pyrolysis liquid (bio-oil). • The phenolics were upgraded into aromatics over Mo-based catalysts by HDO. • The hydro-deoxygenation reaction was carried out at ambient pressure. • The upgrading exhibits good selectivity. • The light oxygenates had little effect on the HDO of phenolics. [ABSTRACT FROM AUTHOR]

Highlights: [•] Photocatalytic activity of the WO3 nanoplates is much higher than commercial WO3. [•] OH is proved the active species responsible for photocatalytic reactions over WO3. [•] The photocatalytic reaction mechanism of the WO3 nanoplates is confirmed. [•] The template-free hydrothermal route is facile, cost effective and can be scaled up. [Copyright &y& Elsevier]

Highlights: [•] A new Cr,Yb,Ho,Eu:YAP laser crystal was grown by the CZ method for the first time. [•] Thermal properties indicate the suitable crystal growth direction is the b axis. [•] Spectroscopic measurements show Cr3+ and Yb3+ can act as sensitizers of Ho3+ ions. [•] Eu3+ ions can act as deactivator in decreasing threshold and increasing efficiency. [ABSTRACT FROM AUTHOR]

• The hydrophobic association PASS was prepared by a base titration method. • PASS with a small amount of lipophilic group could be improving charge neutralization ability. • The crude water containing polymer was effectively treated. • Floc properties were comparatively investigated. The use of oil recovery technologies has resulted in the weakening of interfacial tension between oil and water in oilfield wastewater due to a large amount of polymer present. This leads to the formation of stable emulsified colloidal systems and increases the difficulty of oilfield wastewater treatment. This study investigated hydrophobically-modified polyaluminium silicate sulphate (PASS-C) as a coagulant for oilfield wastewater treatment. PASS-C was prepared by the condensation polymerisation of Al 2 (SO 4) 3 ·18H 2 O with dialysed and hydrolysed KH570 [3-(trimethoxysilyl)propyl methacrylate] under titration with NaAlO 2 and water glass at low temperature. The zeta potential of PASS-C showed that the introduction of hydrophobic groups increased its charge neutralisation ability. Additionally, compared with conventional PASS, PASS-C showed a satisfactory oil removal rate from simulated polymer flooding oily wastewater. When the hydrophobic group content was 1% and the dosage of PASS-C was 140 mg·L–1, the optimal oil removal rate and turbidity removal rate was 95% and 98%, respectively. The particle size and morphology of the coagulated flocs were characterised by laser particle size analysis and SEM. Compared with PASS, PASS-C formed a larger and more compact floc. These findings indicated that the good flocculability of PASS-C for crude oil wastewater was attributable to the synergistic effects of charge neutralisation, hydrophobic associations and adsorption bridging. [ABSTRACT FROM AUTHOR]

Two-dimensional layered semiconductor photocatalysts have attracted much attention due to their excellent performance. Layered photocatalyst, however, generally has low visible-light utilization and is easy to self-polymerize. In this study, layered photocatalyst Ni x Sr 1-x TiO 3 was prepared by doping Nickelin perovskite, and then loaded on RGO with a larger specific surface area. Heterojunction photocatalyst with high performance was successfully prepared. The results show that doping Ni will introduce an occupied energy level between the band gaps, effectively reducing the forbidden bandwidth, and the wavelength of 600 nm still has a high optical response. Much elevated photocatalytic degradation was investigated after further loading Ni x Sr 1-x TiO 3 onto RGO. As a carrier, RGO can improve the self-polymerization of the catalyst and form heterojunction with NixSr1-xTiO 3. The transfer of photogenerated carriers is promoted relying on the potential difference between the two sides of the heterojunction interface and the electron transport channel of RGO. We also noticed that the unique amphoteric molecular properties of RGO can improve the dispersion of Ni x Sr 1-x TiO 3 -RGO in dye wastewater. To sum up, the synergistic effect of reducing band gaps, inhibiting heterojunction structure and improving dispersion are the reasons for more efficient activity. [Display omitted] • 2D lamellar perovskite improves the separation of electron-hole pairs. • The doping of Ni particles broadens the light response range. • NixSr 1-x TiO 3 was successfully loaded on RGO with a larger specific surface area to improve its dispersion. • Heterojunction layered catalysts show better performance. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen sulfide (H2S) is a novel gaseous mediator that plays important roles in atherosclerosis. The present study investigated the effect of a novel H2S-releasing aspirin, ACS14 (2-acetyloxybenzoic acid 4-(3-thioxo-3H-1,2-dithiol-5-yl)phenyl ester), on atherosclerotic plaques in fat-fed apoE–/– mice and the underlying mechanism with respect to CX3C chemokine receptor 1 (CX3CR1) in macrophages. Mouse macrophage cell line RAW264.7 or mouse peritoneal macrophages were preincubated with aspirin (50, 100 or 200μM), ACS14 (50, 100 or 200μM) or vehicle for 6h, and then stimulated with interferon (IFN)-γ (500U/ml) or lipopolysaccharide (LPS; 10μg/ml) for 12h. ACS14, but not aspirin, dose-dependently inhibited IFN-γ or LPS-induced CX3CR1 expression and CX3CR1-mediated chemotaxis in macrophages. The inhibitory effect of ACS14 on CX3CR1 expression was abolished by pretreatment with GW9662, a selective peroxisome proliferator-activated receptor (PPAR)-γ antagonist, suggesting that suppression of macrophage CX3CR1 expression by ACS14 is PPAR-γ dependent. Eight-week-old male apoE–/– mice received intraperitoneal ACS14 (15 or 30μmol/kg/day) or aspirin (15 or 30μmol/kg/day) 4 weeks after fat feeding. Twelve weeks after ACS14 or aspirin treatment, mice were sacrificed to evaluate the extent of atherosclerosis and CX3CR1 expression in brachiocephalic artery (BCA). We found that ACS14, but not aspirin, significantly downregulated CX3CR1 expression in atherosclerotic plaques. ACS14 considerably impeded the formation and development of atherosclerosis as compared to a molar equivalent dose of aspirin. These data indicate that ACS14 may prevent the progression of atherosclerosis by downregulating macrophage CX3CR1 expression via a PPAR-γ-dependent mechanism. [Copyright &y& Elsevier]

Abstract: A new exogenous glutamic acid-independent γ-PGA producing strain was isolated and characterized as Bacillus subtilis C10. The factors influencing the endogenous glutamic acid supply and the biosynthesis of γ-PGA in this strain were investigated. The results indicated that citric acid and oxalic acid showed the significant capability to support the overproduction of γ-PGA. This stimulated increase of γ-PGA biosynthesis by citric acid or oxalic acid was further proved in the 10L fermentor. To understand the possible mechanism contributing to the improved γ-PGA production, the activities of four key intracellular enzymes were measured, and the possible carbon fluxes were proposed. The result indicated that the enhanced level of pyruvate dehydrogenase (PDH) activity caused by oxalic acid was important for glutamic acid synthesized de novo from glucose. Moreover, isocitrate dehydrogenase (ICDH) and glutamate dehydrogenase (GDH) were the positive regulators of glutamic acid biosynthesis, while 2-oxoglutarate dehydrogenase complex (ODHC) was the negative one. [Copyright &y& Elsevier]

Abstract: By using the first-principles calculations based on the density-functional theory (DFT), we study the stability and the nonlinear elasticity of two-dimensional (2D) hexagonal structures of Si and Ge. The reproduced structure optimization and phonon–dispersion curves demonstrate that Si and Ge can form stable 2D hexagonal lattices with low-buckled structures, and provide a good agreement with the previous DFT calculations. The second- and third-order elastic constants are calculated by using the method of homogeneous deformation. The present results of the linear elastic moduli agree well with the previous results. In comparison with the linear approach, the nonlinear effects really matter while strain is larger than approximately 3.5%. The force–displacement behaviors and the breaking strength of 2D hexagonal Si and Ge are discussed using the nonlinear stress–strain relationship. By using the available results of graphene, we reasonably demonstrate that the radius of the atom increases and breaking strength of this element decreases for 2D hexagonal structures of group IV-elements. [Copyright &y& Elsevier]

Poly (β- l-malic acid) (PMLA) is a water-soluble polyester with many attractive properties in chemical industry and medicine development. However, the low titer of PMLA in the available producer strains limits further industrialization efforts and restricts its many potential applications. In order to solve this problem, a new strain with the distinguished high productivity of PMLA was isolated from fresh plants samples. It was characterized as the candidate of Aureobasidium pullulans based on the morphology and phylogenetic analyses of the internal transcribed spacer sequences. After the optimization of culture conditions, the highest PMLA concentration (62.27 g l) could be achieved in the shake flask scale. In addition, the contribution of the carbon flux to exopolysaccharide (EPS) and PMLA could be regulated by the addition of CaCO in the medium. This high-level fermentation process was further scaled up in the 10 l benchtop fermentor with a high PMLA concentration (57.2 g l) and productivity (0.35 g l h), which are the highest level in all the literature. Finally, the suitable acid hydrolysis conditions of PMLA were also investigated with regard to the production of l-malic acid, and the kinetics of PMLA acid hydrolysis was modeled to simulate the whole degradation process. The present work paved the road to produce this multifunctional biomaterial (PMLA) at industrial scale and promised one alternative method to produce l-malic acid in the future. [ABSTRACT FROM AUTHOR]

Abstract: This work proposed a gas sensor for the determination of tert-butyl mercaptan, one of the highly toxic volatile sulfur compounds, which was based on cataluminescence emission during its catalytic oxidation on the surface of nanosized V2O5. The cataluminescence characteristics and the optimum conditions, including the morphology of sensing material, the wavelength of cataluminescence emission, the oxygen flow rate and working temperature were investigated in detail. Under the optimized conditions, the calibration curve of the relative cataluminescence intensity versus the concentration of tert-butyl mercaptan vapor was made, with the linear range of 5.6–196μgmL−1 and the detection limit of 0.5μgmL−1 (S/N =3). The relative standard deviation (R.S.D.) (n =5) of relative cataluminescence intensity for 84μgmL−1 tert-butyl mercaptan was 3.6%. There is no or weak response to some common substances, such as formic acid, alcohol (methanol, ethanol, propanol, isopropanol, n-butanol, isoamyl alcohol), o-dichlorobenzene, acetonitrile, ethyl acetate, aldehyde (formaldehyde, acetaldehyde and propanal), 1,2-dichloroethane and ammonia. Furthermore, the proposed sensor was successfully used for determining tert-butyl mercaptan in four artificial samples, with a good recovery. The results demonstrated that the proposed gas sensor had a promising capability for the tert-butyl mercaptan in routine monitoring. [Copyright &y& Elsevier]

Abstract: The use of electrostatic collection was investigated in quantifying airborne environmental allergens and toxins. The experiments were conducted with two 96-well plates filled with water and placed into the electrostatic sampler designed in this study. The combinations of different electrostatic fields: 0.63, 1.25kV/cm, and different sampling flow rates: 5, 12.5L/min, were tested with the electrostatic sampler. As a reference, a BioSampler operating at 12.5L/min was simultaneously placed in the same environments. The sampling lasted for 40min both for electrostatic sampler and the BioSampler in each test. House dust allergens, endotoxin and (1,3)-β-d-glucans in the air samples collected were analyzed using enzyme-linked immunosorbent assay (ELISA) and Limulus amebocyte lysate (LAL) method, respectively. The entire experiments were conducted both in office environment and hotel rooms. The concentrations of airborne allergens (Der p 1 and Der f 1) and toxins (endotoxin and (1,3)-β-d-glucans) obtained by the electrostatic sampler were shown significantly higher than those by the BioSampler in most cases. Paired t-tests (n=9) indicated that the sampling difference was statistically significant (p-value <0.05). For allergens, the concentration ratio was up to 5.6, and for toxins the concentration ratio was up to 10.8 when the electrostatic sampler was operated at 1.25kV/cm and 5L/min. In general, the concentration ratio decreased for both allergens and toxins when the electrostatic field strength decreased or when the sampling flow rate increased for the electrostatic sampler. Paired t-tests (n=9) also indicated there were statistically significant effects of electrostatic field strength and the sampling flow rates on the performance of the electrostatic sampler when collecting the airborne allergens and toxins. This study presented an airborne environmental allergen and toxin monitoring technology, which holds broad promise for detecting and quantifying low level environmental allergen and toxins. [Copyright &y& Elsevier]

Accumulating evidence has suggested that hydrogen sulfide (H2S) is endogenously generated in many types of mammalian cells. Since H2S plays an important role in cardiovascular, central nervous and gastrointestinal systems, it is currently considered to be the third gaseous mediator. Recently, more and more attention has been paid to the biological functions of H2S in inflammation. In various animal models of inflammatory diseases (such as acute pancreatitis, sepsis and endotoxemia), endogenous H2S has been shown to be overproduced and participate in regulating the severity of inflammatory response and associated organ injury. Inhibition of H2S formation is likely to protect animals against these inflammatory diseases. H2S may exert its effect on inflammation via regulating the function of leukocytes, leukocyte trafficking and immune cell survival. Furthermore, H2S has been suggested to induce the release or production of neuropeptides (substance P and calcitonin gene-related peptide), which are considered to be pro-inflammatory mediators, and therefore contribute to inflammatory response. In addition, some studies reported that low doses of sodium hydrosulfide (NaHS, an H2S donor) exhibited some anti-inflammatory effect on local inflammation (such as non-steroidal anti-inflammatory drug-induced gastric injury). Taken together, all these findings demonstrate that in addition to the vasodilation and neuromodulation activity of H2S, it may contribute to the pathogenesis of inflammatory diseases via regulating the activation of leukocytes. [ABSTRACT FROM AUTHOR]

Angiopoietin-2 (Ang2) promotes tumor growth and metastasis by specifically priming endothelial cells for angiogenesis. Multiple angiogenic factors up-regulate expression of Ang2, suggesting that Ang2 may be the common pathway in growth factor initiated-angiogenesis. Using phage display technology, we generated single chain Fv molecule against human Ang2 (scFv–Ang2) with high affinity (Kd=0.01 μM) from a mouse phage antibody library. Compared with control scFv, the mouse scFv–Ang2 completely inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) treated with vascular endothelial growth factor (VEGF, 10 ng/ml), but not that of the cells treated with either basic fibroblast growth factor, or angiotensin II, or Ang2. Chemotaxis assay showed that scFv–Ang2 could block completely Ang2-induced (100%) and partially VEGF-induced (49%) migration of HUVECs. The results indicate that Ang2 takes part in the VEGF-induced angiogenesis and scFv–Ang2 might be a promising compound in blocking both VEGF and Ang2 induced angiogenesis. [Copyright &y& Elsevier]

As a hybrid of the Parallel Two-stage Flowshop problem and the Multiple Knapsack problem, we investigate the scheduling of parallel two-stage flowshops under makespan constraint, which was motivated by applications in cloud computing and introduced by Chen et al. [3] recently. A set of two-stage jobs are selected and scheduled on parallel two-stage flowshops to achieve the maximum total profit while maintaining the given makespan constraint. We give a positive answer to an open question about its approximability proposed by Chen et al. [3]. More specifically, based on guessing strategies and rounding techniques for linear programs, we present a polynomial time approximation scheme (PTAS) for the case when the number of flowshops is a fixed constant. As the case with two flowshops is already strongly NP-hard, our PTAS achieves the best possible approximation ratio. [ABSTRACT FROM AUTHOR]

Bio-aviation fuels are a major research and development topic, with strong interests from the aviation sector, the public, lawmakers and potential producers. Yet the development and market penetration in the air-transportation sector is slow, despite proven environmental benefits. Bio-fuels can indeed mitigate the environmental impact of the aviation sector mostly due to their low carbon intensity and favourable chemical structure. Such bio-aviation fuels must have "drop-in" characteristics with specifications and compatibility with the combustion behaviour of kerosene. The ASTM approval procedures are an important guarantee in this respect. Additional emission reductions rely on the production pathways, while optimum flight-related strategies are an additional benefit. An analysis of both the production pathways, and the environmental and Life Cycle Assessment findings delineates important research directions to enhance the production and use of bio-aviation fuels. Towards specific environmental issues , target research topics should include various topics. A better quantification of particulate and soot emissions, condensation contrails and NO x are of primary concern. The impact of geographic parameters on the bio-aviation fuel benefits should be investigated towards using bio-aviation fuels primarily in specific climate zones. Emission prediction models should be further developed. LCA approaches should be extended. More on-flight emission patterns should be measured to provide relevant data for the above considerations; Towards bio-aviation fuel characterization , safety and reliability are major criteria of the ASTM approval. Towards production pathways , the technical viability studies of synthesis pathways should be combined with economic assessments. Towards fuel costs, the reason for the high production cost of bio-aviation fuel is at least partly due to the oxygen-rich bio-polymer nature of biomass with unsuitable carbon chain length. In order to reduce the cost of bio-aviation fuel, several research directions are encouraged and discussed in the paper. Image 1 [ABSTRACT FROM AUTHOR]

A Nd3+-doped Y 2.8 ScAl 4.2 O 12 (Nd:YSAG) single crystal was grown successfully via the Czochralski technology. The crystal structure and crystalline quality of the as-grown Nd:YSAG crystal were determined by the X-ray powder diffraction and X-ray rocking curve, respectively. By X-ray fluorescence analysis, the effective segregation coefficient of Nd3+ is calculated to be 0.33 in the YSAG crystal. Using the chemical etching method, the dislocation density on the (111)-crystalline face is obtained to be about 3.45 × 102 cm−2. The large absorption cross-section (2.95 × 10−20 cm2) and wide FWHM (9.8 nm) around 808.8 nm imply a high LD pumping efficiency. The high emission cross-section (3.53 × 10−20 cm2) at 1336.3 nm and long fluorescence lifetime of Nd3+ ions (286.20 μs) are beneficial to realize laser output. Thereby, all the results indicate that the Nd:YSAG crystal is a potentially new gain material pumped by a LD for near-infrared laser at 1336.3 nm. • A Nd3+:Y 2.8 ScAl 4.2 O 12 crystal was grown successfully by the Czochralski method. • Dislocation density on the (111)-crystalline face is obtained to be 3.45 × 102 cm−2. • A large absorption cross-section (2.95 × 10−20 cm2) implies high pumping efficiency. • High emission cross-section (3.53 × 10−20 cm2) is beneficial to realize 1336.3 nm laser. • All results indicate this crystal is a potential gain material for 1336.3 nm laser. [ABSTRACT FROM AUTHOR]

Hydrogen is a common reactant in the petro-chemical industry and moreover recognized as a potential fuel within the next 20 years. The production of hydrogen from biomass and carbohydrate feedstock, though undoubtedly desirable and favored, is still at the level of laboratory or pilot scale. The present work reviews the current researched pathways. Different types of carbohydrates, and waste biomass are identified as feedstock for the fermentative bio-hydrogen production. Although all techniques suffer from drawbacks of a low H 2 yield and the production of a liquid waste stream rich in VFAs that needs further treatment, the technical advances foster the commercial utilization. Bacterial strains capable of high hydrogen yield are assessed, together with advanced techniques of co-culture fermentation and metabolic engineering. Residual VFAs can be converted. The review provides an insight on how fermentation can be conducted for a wide spectrum of feedstock and how fermentation effluent can be valorized by integrating fermentation with other systems, leading to an improved industrial potential of the technique. To boost the fermentation potential, additional research should firstly target its demonstration on pilot or industrial scale to prove the process efficiency, production costs and method reliability. It should secondly focus on optimizing the micro-organism functionality, and should finally develop and demonstrate a viable valorization of the residual VFA-rich waste streams. • Hydrogen is a common reactant in the chemical industry and a potential fuel. • Review of the current researched fermentation bio-hydrogen pathways. • New developments (e.g. metabolic engineering, H 2 separation) are assessed. • Fermentation has low H 2 production yields. The fermentation effluent, rich in VFAs, needs further treatment. [ABSTRACT FROM AUTHOR]

Poly(β-L-malic acid) (PMLA) is a water-soluble, biodegradable, and biocompatible polymer with broad prospective applications and can be hydrolyzed to produce widely used acidulant L-malic acid. In order to meet an increasing demand of PMLA, we employed two effective cell-recycling strategies to produce PMLA from raw cassava hydrolysate by Aureobasidium pullulans ZD-3d. In fed-batch fermentation with raw cassava hydrolysate, 101.9 g/L PMLA was obtained with the productivity and yield of 0.77 g/L/h and 0.40 g/g, respectively. Further, three times of membrane filtration–based cell recycling fermentation was carried out, with a high productivity and yield of 1.04–1.64 g/L/h and 0.5–0.84 g/g achieved, respectively. While harnessing centrifugation-based cell recycling fermentation for five times, the productivity and yield approached 0.98–1.76 g/L/h and 0.78–0.86 g/g, respectively. To our knowledge, the processes showed the highest average PMLA productivity compared with others using low-cost biomass, which offered efficient and economical alternatives for PMLA production. Key points: • PMLA production from raw cassava hydrolysate by Aureobasidium pullulans was studied • High PMLA productivity and yield were obtained via two cell recycling strategies • The highest average PMLA productivity from low-cost biomass to date was achieved [ABSTRACT FROM AUTHOR]

A novel mid-infrared (Er 0.3 Lu 0.1 Y 0.6) 3 Ga 5 O 12 laser crystal is successfully grown by the Czochralski method, the crystal structure, segregation coefficient, thermal performance, spectroscopy and 2.8 μm laser performance are studied systematically. The crystal possesses a pure garnet phase with a thermal conductivity of 4.54 W m−1 K−1. It exhibits a broader absorption band around 966 nm and some strong emission peaks at 2.6–3 μm, corresponding to the absorption cross-section of 1.39 × 10−21 cm2 at 966 nm and emission cross-section of 1.25 × 10−20 cm2 at 2822 nm, respectively. The level lifetimes of 4I 11/2 and 4I 13/2 are fitted to be 0.885 and 3.203 ms. A LD end-pumped Er:LuYGG laser has been demonstrated, achieving a maximum output power of 339 mW and a slope efficiency of 17.77 %. The primary laser wavelength is centered at 2824.76 nm. All the results indicate that the Er:LuYGG crystal is a novel and promising crystal material to realize the 3 μm laser. • A novel Er:LuYGG crystal is successfully grown by the Cz method. • Growth, thermal, spectroscopy and laser performance of Er:LuYGG crystals were studied. • A LD end-pumped Er:LuYGG laser is demonstrated with maximum output power of 339 mW. • The Er:LuYGG crystal is a potential and promising candidate to realize the 3 μm laser. [ABSTRACT FROM AUTHOR]

The fabrication of poly(vinylidene fluoride) (PVDF) based foam with complicated three-dimensional (3D) geometry and excellent piezoelectric property remains great challenge worldwide. In this study, microcellular PVDF/multiwalled carbon nanotube (MWCNT) nanocomposite foaming part was fabricated by supercritical carbon dioxide (scCO 2) bead foaming technology. With the assistance of the ball milling, the good dispersion of MWCNT particles in PVDF matrix was achieved, which promoted the heterogeneous nucleation and enhancement effects of MWCNT on PVDF, resulting in the formation of more unique and denser cells, e.g. from 3.4 × 105 cells/cm3 of pure foam to 1.7 × 106 cells/cm3 of the composite foam when MWCNT content was 1.5%, and high compression strength, i.e. 3.1 MPa with 1.5% MWCNT at 10% compressive strain, about 1.1 MPa higher than that of pure foam. During the bead foaming process, the induced crystallization effect of MWCNT as well as the plasticizing and squeezing effect of scCO 2 on PVDF matrix contributed to the increase of the β-phase crystal in PVDF matrix, thus endowing the composite foaming part with good piezoelectric property, i.e. 6.5 V of output voltage under periodic compression, which lightened 4 LEDs and made the foaming part had wide potential application in smart electronic field. [ABSTRACT FROM AUTHOR]

Yb3+ and Ho3+ co-doped Lu2.55Y0.45Al5O12 (Yb,Ho:LuYAG) crystal with a size of Φ 28 mm × 120 mm was successfully grown by the Czochralski method. The lattice parameters of the as-grown Yb,Ho:LuYAG crystal were obtained by Rietveld refinement with the XRD data. The result of X-ray rocking curve indicated that the grown crystal has a high crystalline quality. From strong absorption band near 935 nm and emission bands within 2700–3000 nm, we found that the Yb3+ ions can be acted as the sensitizer for the activator ions Ho3+. Furthermore, the lifetimes of the 5I6 and 5I7 levels of the Ho3+ ions were 68.25 μs and 7.58 ms, respectively. These results indicated that the Yb,Ho:LuYAG crystal is a promising gain material for 2.91 μm laser pumped by a 940 nm LD. [ABSTRACT FROM AUTHOR]

The control of laccase-catalyzed efficiency often relies on the utilization of modifying enzyme molecules and shielding agents. However, their elevated costs or carcinogenicity led to the inability for large-scale application. To address this concern, we found that a low-cost protein from soybean meal can reduce lignin's ineffective adsorption onto enzymes for improving the efficiency of thymol grafting to lignosulfonate. The results demonstrated that by adding 0.5 mg/mL of additional soybean meal protein, the thymol reaction ratio of the modified lignosulfonate (L-0.5 S) significantly boosted from 18.1 % to 35.0 %, with the minimal inhibitory concentrations of the L-0.5 S against Aspergillus niger dramatically improved from 12.5 mg/mL to 3.1 mg/mL. Multiple characterization methods were employed to better understand the benefit of the modification under the addition of the soybean meal protein. The C O and R 1 -O group content increased from 20.5 % to 37.8 % and from 65.1 % to 75.5 %, respectively. The proposed potential reaction mechanism was further substantiated by the physicochemical properties. The incorporation of soybean meal effectively mitigated the non-specific adsorption of lignosulfonate, resulting in a reduction of the surface area of lignin from 235.0 to 139.2 m2/g. The utilization of soybean meal as a cost-effective and efficient shielding agent significantly enhanced the efficiency of subsequent enzyme catalysis. Consequently, the application of soybean meal in commercial enzyme catalysis holds considerable appeal and amplifies the relevance of this study in preservative industries. [ABSTRACT FROM AUTHOR]

Large lattice constant Y3Al5O12, Gd3Ga5O12 (GGG), Y3Sc2Ga3O12 (YSGG), Gd3Sc2Ga3O12, Ca0.4Mg0.25Zr0.65Gd2.6Ga4.1O12 (CaMgZr:GGG), and Gd1.17Y1.83Sc2Ga3O12 (GYSGG) substrate crystals with 2 in. in diameter are grown by the Czochralski (Cz) method, their physical, chemical, and optical properties are analyzed and compared in details. The X‐ray rocking curves (XRCs) illustrate that the as‐grown crystals possess high crystalline quality. The lattice constants of six crystals are calculated and that of GYSGG can be easily adjusted in the range of 1.2450–1.2565 nm by changing the Gd/Y proportion. The dislocation densities on the (111)‐crystalline face are about 102 cm−2 order of magnitude. The thermal conductivities of six crystals are measured to be 11.72, 8.98, 6.83, 5.45, 4.67, and 4.66 W m−1 K−1, respectively. It is found that the thermal expansion coefficients of six crystals can be reduced by annealing at 1273 K for 60 h. In addition, the transmission spectra show that the six crystals have excellent transparency and the coefficients of the Sellmeier equation are fitted by the calculated refractive indices. These results of the six crystals can provide the necessary parameters and references for the selection of suitable substrate materials or laser host crystals. [ABSTRACT FROM AUTHOR]

• Er,Pr:YAP crystals with two different Pr3+ concentrations are grown by CZ method. • Influence of Pr3+ concentrations on the luminescence and laser properties are investigated contrastively. • Watt-level ∼2.7 μm laser is achieved on the Er,0.1Pr:YAP crystal by LD end-pumping. • ∼2.7 μm laser power can be improved by optimizing the concentrations of deactivating Pr3+. High-quality Er,Pr:YAP crystals with two different Pr3+ concentrations are grown successfully, and the spectra and laser performances are studied in contrast. Both two crystals exhibit a wide absorption band with a central wavelength at 972 nm and high transmittance of over 80% in the wavelength range of 2.5 to 5 μm. The luminescence and laser properties are improved when the concentration of Pr3+ decreased from 0.2 at% to 0.1 at%. The maximum powers of 1040 and 835 mW are achieved in the Er,0.1Pr:YAP, and Er,0.2Pr:YAP crystals, corresponding to slope efficiencies of 13.97% and 10.94%, respectively. All the results indicate that co-doping with an appropriate concentration of deactivating Pr3+ is an effective method to attenuate the self-termination effect of Er3+, and then further improve the laser performance. [ABSTRACT FROM AUTHOR]

Five substituted gadolinium gallium garnet crystals with different Ca2+/Mg2+/Zr4+ stoichiometric ratio concentrations (Zr4+: 13.0, 15.0, 15.3, 16.3, 19.5 at.%, as well as increasing Ca2+ and Mg2+ concentrations in proportion) were grown by Czochralski technique. Their structure, defect, thermal and optical properties were comparatively studied and analyzed. The lattice parameters are achieved to be 12.47–12.54 Å which are 0.7–1.2 % larger than that of Gd 3 Ga 5 O 12. A linear equation with Zr4+ concentration is fitted to adjust the lattice parameter for demand. X-ray rocking curves with narrow FWHMs of 1.67′, 1.97′, 1.75′, 2.12′, 2.99′, respectively, indicating high crystalline quality when the Zr4+ concentration is below 16.3 at.%. The dislocation densities are 62, 47, 63, 315 and 3184 cm−2, suggesting the value increases rapidly when the Zr4+ concentration exceeds 16.3 at.% due to large lattice distortion. The thermal expansion coefficients are about 8.55 × 10−6 to 8.72 × 10−6 K−1, respectively. All the transmittances are above 80 % from visible to infrared wavelengths, and Sellmeier coefficients of refraction index equation were fitted, which is benefit for CaMgZr:GGG as substrate and optics application. The above results suggest that a more suitable substrate can be obtained for the series YIG magnetic-optic thin films by optimizing the Ca2+/Mg2+/Zr4+ concentrations. ● Five SGGG single crystals with different Ca2+/Mg2+/Zr4+ concentrations were successfully grown by Cz method. ● Relationship of concentrations and lattice constants can be described by fitting equation to adjust lattice parameter better. ● The Ca2+/Mg2+/Zr4+ concentrations have significative effect on crystalline quality, dislocation density and thermal expansion. ● Experimental refractive index and energy gaps data for different SGGG single crystals are provided. ● Potential and economic application value of SGGG in laser gain medium or substrate for series YIG magneto-optical thin films. [ABSTRACT FROM AUTHOR]

β-Farnesene is an advanced molecule with promising applications in agriculture, the cosmetics industry, pharmaceuticals, and bioenergy. To supplement the shortcomings of rational design in the development of high-producing β-farnesene strains, a Metabolic Pathway Design-Fermentation Test-Metabolomic Analysis-Target Mining experimental cycle was designed. In this study, by over-adding 20 different amino acids/nucleobases to induce fluctuations in the production of β-farnesene, the changes in intracellular metabolites in the β-farnesene titer-increased group were analyzed using non-targeted metabolomics. Differential metabolites that were detected in each experimental group were selected, and their metabolic pathways were located. Based on these differential metabolites, targeted strain gene editing and culture medium optimization were performed. The overexpression of the coenzyme A synthesis-related gene pantothenate kinase (PanK) and the addition of four mixed water-soluble vitamins in the culture medium increased the β-farnesene titer in the shake flask to 1054.8 mg/L, a 48.5% increase from the initial strain. In the subsequent fed-batch fermentation, the β-farnesene titer further reached 24.6 g/L. This work demonstrates the tremendous application value of metabolomics analysis for the development of industrial recombinant strains and the optimization of fermentation conditions. [ABSTRACT FROM AUTHOR]

A novel series of ocotillol-type triterpenoid derivatives have been synthesized to evaluate for their antibacterial activity, structure-activity relationships (SARs), and antibacterial mechanism. Compound (Vl), which were found to be the most active one, displayed good antibacterial activity with minimum inhibitory concentrations (MICs) of 2–8 μg/mL against Gram+ bacteria and 8–32 μg/mL against Gram– bacteria. Further testing against drug-resistant bacteria also showed that (Vk) and (Vl) exhibited potent antibacterial activity with MICs of 4–32 μg/mL against MRSA and K. pneumonia. The following synergistic antibacterial activity revealed that compound (Vl) significantly improved the susceptibility of MRSA USA300 and E.coli DH5α to kanamycin and chloramphenicol. Further research suggested that (Vl) displayed obvious bactericidal activity against MRSA at 2 MIC while it only showed bacteriostatic effects at MIC. This active molecule (Vl) also induced bacterial resistance more slowly than norfloxacin and chloramphenicol. Moreover, compound (Vl) not only had low toxicity, but also could rapidly inhibit the growth of drug-resistant bacteria by damaging cell membranes, and the incidence of drug resistance was obviously lower than that of positive control group. Additionally, the properties of absorption, distribution, metabolism, and excretion (ADME) of these compounds demonstrated their drug-likeness with moderate oral absorption and blood-brain barrier permeability. Preliminary in vivo results also confirmed that (Vl) could reduce the number of viable colonies in the infected cornea at a high concentration (3.2 mg/mL). These results suggested that ocotillol-type triterpenoid derivatives represent as potential leads for the development of antibacterial agents against antibiotic-resistant superbugs and deserve further attention. [ABSTRACT FROM AUTHOR]

Uncovering mechanisms underlying epileptogenesis aids in preventing further epilepsy progression and to lessen seizure severity and frequency. The purpose of this study is to explore the antiepileptogenic and neuroprotective mechanisms of EGR1 in neuron injuries encountered in epilepsy. Bioinformatics analysis was conducted to identify the key genes related to epilepsy. The mice were rendered epileptic using the kainic acid protocol, followed by measurement of seizure severity, high amplitude and frequency, pathological changes of hippocampal tissues and neuron apoptosis. Furthermore, an in vitro epilepsy model was constructed in the neurons isolated from newborn mice, which was then subjected to loss- and gain-of-function investigations, followed by neuron injury and apoptosis assessment. Interactions among EGR1, METTL3, and VIM were analyzed by a series of mechanistic experiments. In the mouse and cell models of epilepsy, VIM was robustly induced. However, its knockdown reduced hippocampal neuron injury and apoptosis. Meanwhile, VIM knockdown decreased inflammatory response and neuron apoptosis in vivo. Mechanistic investigations indicated that EGR1 transcriptionally activated METTL3, which in turn downregulated VIM expression through m6A modification. EGR1 activated METTL3 and reduced VIM expression, thereby impairing hippocampal neuron injury and apoptosis, preventing epilepsy progression. Taken together, this study demonstrates that EGR1 alleviates neuron injuries in epilepsy by inducing METTL3-mediated inhibition of VIM, which provides clues for the development of novel antiepileptic treatments. [ABSTRACT FROM AUTHOR]

40 small watersheds in the Source Area of the Yellow River were investigated recently to sample surface waters, groundwater and ground ice, and their water isotopic signatures (2H, 18O, 3H, and 222Rn) have been measured. A novel isotope mass balance approach was developed to estimate annual surface and surface flow discharges in catchment combined water age dating. This approach revealed the changing surface and subsurface runoff patterns were along the hydrological trajectory of progressive permafrost degradation. To build up the linkages between the hydrological indictors and environmental and biological features was recommended, which would benefit a better understanding the significant impacts of permafrost degradation on social, ecological and economic developments in cold regions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to obtain large deviations, moderate deviations and normal deviations for the convergence of martingale generated by a supercritical Galton–Watson process with a Poisson process as its time index. Harmonic moments and Shröder index play an important role in the proofs. [ABSTRACT FROM AUTHOR]

In this paper, we study an on-line scheduling problem that is motivated by applications such as carpooling. The ride requests arrive on-line over-list and specify the service locations (among m locations). The goal is to determine a schedule that maximizes the number of satisfied requests using k servers. We consider two variants of the problem with respect to constraints on the service location: in the monotone service direction variant, the service locations of the requests assigned to a server must be monotonic; in the strict monotone service direction variant, the service locations must be strictly monotonic. We present lower bounds on the competitive ratio for both variants. For the monotone service direction variant, we give an optimal straightforward algorithm if k ≥ m and we prove that no deterministic on-line algorithm can achieve a constant competitive ratio if k < m. For the strict monotone service direction variant, we give a lower bound max ⁡ { 2 (m − 1) m , 1 } on the competitive ratio of barely deterministic algorithms if k > 2 , and a lower bound of max ⁡ { m 2 , 1 } if k ≤ 2. We propose a Balanced Interval Algorithm for the strict monotone service direction variant if k > 2 and report some numerical experiments to evaluate the efficiency of this algorithm. • We introduce two on-line algorithm problems with monotone service direction constraints which are applied for carpooling system. • We discuss the lower bounds and upper bounds of these two problems. • We propose a balanced interval algorithm and measure the algorithm performance with numerical experiments. [ABSTRACT FROM AUTHOR]

In this study, the effects of dicyclohexylcarbodiimide (DCC) and disodium succinate (DS) treatments on the pericarp browning (PB) development in postharvest longan were elucidated by measuring PB-related phenotypes and the metabolisms of antioxidants, membrane lipids, and phenolics. Compared to the control, DCC-treated longan displayed the higher levels of PB index, CMP, ROS, PA, DAG, and SFAs, the higher activities of POD, PPO, and MLMEs including PLD, PC-PLC, PI-PLC, lipase, and LOX, and the higher expression levels of DlPPO1 , DlPOD1 , and genes encoding MLMEs. In contrast, the lower levels of chromaticity values, pigments, TP, PC, PI, and USFAs, the lower activities of RSEs including SOD, CAT, and APX, the lower expression levels of genes encoding RSEs, and a lower non-enzymatic antioxidant capacity were also noted in DCC-treated longan. These results imply that the exacerbated PB induced by DCC was associated with the activation of MLMEs by up-regulating the expression of genes encoding MLMEs, which expedited the damage of cell membrane. This membrane damage was also regulated by the accelerated accumulation of ROS triggered by DCC. The increased membrane permeability after the damage prompted an enzymatic oxidation between phenol oxidase and phenolics. However, the opposite effect occurred in the DS-treated longan. • DCC accelerated pericarp browning, but DS delayed pericarp browning in fresh longan. • DCC lowed antioxidant ability, but DS raised antioxidant ability in longan pericarp. • DCC induced ROS accumulation in longan pericarp, but DS showed the reverse effects. • DCC promoted cell membrane damage of longan pericarp, but DS retarded this damage. • DCC raised phenolics oxidation in longan pericarp, but DS delayed this process. [ABSTRACT FROM AUTHOR]

Abstract The advanced treatment of industrial wastewater often calls upon the use of highly-efficient treatment methods to remove hazardous pollutants prior to the effluent discharge. Adsorption can be used towards removing micro-pollutants. Congo Red dye is widely used in the paper and textile industry, and residual quantities are present in the process effluents. Adsorbing metal oxide nanoparticles have abundant pores of appropriate size, a large specific surface area, and can efficiently remove organic pollutants from waste water. Fe x Co 3-x O 4 nanoparticle adsorbents were synthesized. Their magnetic properties facilitate their recovery. Experiments were conducted for different Congo Red concentrations and Fe x Co 3-x O 4 nanoparticles dosage. The maximum Congo Red adsorption capacity of Fe x Co 3-x O 4 nanoparticles at equilibrium was 128.6 mg/g. The adsorption yield of Congo Red decreased from 86.12% to 79.53% when the initial concentration of Congo Red increased from 10 mg/L to 30 mg/L, Adsorption results were modeled to define essential parameters such as the adsorption mechanisms and kinetics. A pseudo-first-order kinetic model fitted the results. The equilibrium adsorption data were moreover fitted by isotherm models, with both the Langmuir and Freundlich equations shown appropriate. The re-use of the nanoparticle adsorbent was moreover investigated for 5 successive adsorption cycles, without loss of adsorption capacity. A case study for the adsorption of Congo Red on the Fe x Co 3-x O 4 nanoparticles demonstrates that the required mass of adsorbent can be calculated for any amount of Congo Red to be removed. It was demonstrated that the fairly cheap and environmentally friendly Fe x Co 3-x O 4 nanoparticles have a strong adsorption and removal ability for dyes and are easy to recycle. Graphical abstract Image 1 Highlights • Fe x Co 3-x O 4 nanoparticles were synthesized and used as adsorbent in water treatment. • Experiments were conducted for different Congo Red concentrations and Fe x Co 3-x O 4 nanoparticles dosage. • Adsorption results were modeled to define essential parameters such as the adsorption mechanisms and kinetics. • Fe x Co 3-x O 4 nanoparticles have strong dye adsorption and removal ability, and are eco-friendly, recyclable and inexpensive. [ABSTRACT FROM AUTHOR]

• Cr,Er:YSGG crystal with thermal bonding and concave end-face is pumped by Xenon lamp. • Thermal distribution simulation shows thermal bonding can improve heat dissipation capability. • Thermal focal length indicates concave end-face can compensate thermal lens effect. • High single pulse energy of 3.48 J obtained for the concave thermal bonding Cr,Er:YSGG at 5 Hz. • Maximum energy of 1.155 J and slope efficiency of 3.65 % are achieved for the concave thermal bonding Cr,Er:YSGG at 20 Hz. We demonstrate the influence of thermal bonding and concave end-face on the 2.79 μm laser performance of Cr,Er:YSGG crystal. The simulation results of temperature distribution suggest that the two pure YSGG crystals bonded on the Cr,Er:YSGG as end-caps are beneficial to improve the heat dissipation capability. The experimental results of thermal focal length show that the thermal effects of un-bonding, planar thermal bonding, and concave thermal bonding Cr,Er:YSGG crystals are in descending tendency. The maximum output energies and slope efficiencies for concave thermal bonding Cr,Er:YSGG crystal are 3.480 J, 3.33 %@5 Hz; 2.126 J, 3.65 %@10 Hz; 1.384 J, 3.63 %@15 Hz; 1.155 J, 3.65 %@20 Hz, respectively, and the beam quality factors M x 2/ M y 2 are determined to be 7.68/8.63. The result is much better than the previous work, indicating that the xenon lamp pumped concave thermal bonding Cr,Er:YSGG crystal is a promising method to realize high energy laser output. All the results indicate that the thermal bonding and concave end-faces are promising methods to reduce the thermal effect and improve the laser performance of Cr,Er:YSGG crystal pumped by the xenon lamp. [ABSTRACT FROM AUTHOR]