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Saccharomyces cerevisiae is an important microbial organization involved in ethanol synthesis. Mutant strains that can withstand multiple pressures during this process are critical to the industrial development of biofuels. In this study, a dual high-throughput screening method of Triphenyl-2H-tetrazoliumchloride (TTC)-based macroscopic observation and the reaction of ferric nitrate with pyruvate (or pyruvate radical ion) in fermentation broth was used. Using this, an S. cerevisiae mutant library that could tolerate 381 g/L sucrose was established by ARTP random mutation and adaptive evolution to select the best strain; its ethanol yield was increased by an additional 20.48%; and the sucrose utilization rate was 81.64%. This method is specific to the selection of strains with increased ethanol production.

In this paper, magnetically actuated tunable liquid lens is fundamentally studied to have further potential application scope in research, industrial, aeronautical and astronautical areas. The magnetic field, which is generated by a magnetic potential applied to the permanent magnet domain, distributes non-uniformly in the computational domain and generates magnetic field force to obtain the deformation of the ferrofluid droplet. Consequently, the light-transmitting droplet deforms due to direct contact with the ferrofluid droplet by a connecting channel. The combined effects of gravitational, frictional, interfacial and pressure-driven force make light-transmissive droplet to be a programmable liquid lens. The light-transmissive droplet exhibits changes in the curvature of the contour, which results in different focal lengths for realizing the variable-focus liquid lens. This work focus on the driven mechanism by the magnetic force for a better understanding. The performance is numerically studied for a magnetically actuated varifocal liquid lens by finite element method. The results are presented individually for the distribution of magnetic and flow field, and light refraction.

A significant growth of research on adaptive liquid lens is achieved over the past decades, and the field is still attracting increasing attentions, focusing on the transition from the current stage to the commercialized stage. The challenges faced are not limited to fabrication, material, small tuning range in focal lengths, additional control systems, limitations in special actuation methods and so on. In addition, the use of external driving parts or systems induce extra problem on bulky appearance, high cost, low reliability etc. Therefore, adaptive liquid lens will be an interesting research focus in both microfluidics and optofluidics science. This review attempts to summarize and focus on the droplet profile deformation under different driving mechanisms in tunable liquid microlens as well as the application in cameras, cell phone and so on. The driving techniques are generally categorized in terms of mechanisms and driving sources.

A gene (gkdA) (741 bp) encoding a putative protein of 247 amino acids was cloned from the Bacillus licheniformis SR01. The protein was expressed in Escherichia coli BL21 with a molecular mass estimated by SDS-PAGE of approximately 28.03 kDa and showed a calculating isoelectric point (pI) of 6.42. Structure analysis and function identification showed that the enzyme was a multifunctional glycosidase. Its specific activity was 0.013 U/μg. The recombinant glycosidase showed a maximum activity at 50°C and pH 7.0. It was very stable below 90°C and may have heat activation at higher temperatures. The relative residual activity was still more than 80% after 120 min at pH 5.0-10.0. The enzyme activity was inhibited by Cu

Little is known about the mechanism(s) by which alpha-interferon (aIFN), when used as a biotherapeutic agent, suppresses the malignant cells and restores the normal phenotype of cells in patients with hairy cell leukemia (HCL). In previous studies using scanning electron microscopy (SEM) we found that alFN induced unique membrane alterations in target hairy cells in vitro. In addition, aIFN was shown to enhance the expression of HLA class II antigens on HCL cells, to induce the production of new proteins in such cells, and to lower the high levels of soluble IL-2 receptors in the serum of HCL patients. In the light of these results, and the fact that restoration of natural killer cell activity occurs in aIFN-treated patients well after the hematologic profile begins to improve, our studies have focused on the hypothesis that IFNs act directly on the target malignant cells, leading to the elimination of these cells either by inhibiting the proliferation of the malignant cells and/or triggering changes in the differentiation status of the malignant cells that lead to suppression (cytoconversion) of the malignant phenotype. We review the current hypotheses regarding alFN action on leukemic cells, with special reference to its potential antagonism with BCGF.

The in vitro antimicrobial activity of the essential oil from needles of Pinus yunnanensis Franch.var tenuifolia was investigated. The essential oil was obtained by hydro-distillation and analyzed by gas chromatography-mass spectrometry (GC-MS) method. The major compound of the essential oil was α-pinene (22.542%), followed by β-caryophyllene (16.636%), 1,2,4a,5,8,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-naphthalene (5.085%), β-cubebene (4.779%), elixene (4.442%), α-cadinol (3.528%),α-caryophyllene (3.459%) and limonene (3.428%). The antimicrobial activity of oil was evaluated by using disc diffusion and agar dilution methods, respectively. The results indicated that the essential oil held moderate antimicrobial activity against tested microorganisms. The essential oil did not differ remarkably in its antibacterial and antifungal activities. The minimum inhibitory concentrations (MICs) were 40 ml/l for bacterial strains, and 80 ml/l for fungal strains.

The purpose of remote sensing images fusion is to produce a fused image that contains more clear, accurate and comprehensive information than any single image. A novel fusion method is proposed in this paper based on nonsubsampled contourlet transform (NSCT) and region segmentation. Firstly, the multispectral image is transformed to intensity-hue-saturation (IHS) system. Secondly, the panchromatic image and the component intensity of the multispectral image are decomposed by NSCT. Then the NSCT coefficients of high and low frequency subbands are fused by different rules, respectively. For the high frequency subbands, the fusion rules are also unalike in the smooth and edge regions. The two regions are segregated in the panchromatic image, and the segmentation is based on particle swarm optimization. Finally, the fusion image can be obtained by performing inverse NSCT and inverse IHS transform. The experimental results are evaluated by both subjective and objective criteria. It is shown that the proposed method can obtain superior results to others.

Psoriasis is a chronic inflammatory skin disease affecting 1-3% of the world's population. Traditional Chinese medicines have been extensively used for treating psoriasis with promising clinical results. Celastrol, a triterpenoid isolated from a Chinese herb Celastrus orbiculatus caulis, has been known to have diverse pharmacological effects such as anti-inflammatory, anti-cancer and antioxidant activities. The present study aimed at evaluating the anti-proliferative action of celastrol on cultured HaCaT cells and elucidating the mechanisms of action involved. Celastrol was shown to inhibit HaCaT cells growth with an IC₅₀ value of 1.1 μM as measured by MTT assay. The ability of celastrol to induce apoptosis was studied by flow cytometric and western blot analyses. Celastrol was found to be capable of inducing apoptosis in HaCaT cells as characterized by phosphatidyl-serine (PS) externalization, depolarization of mitochondrial membrane potential and activation of caspase-3. The apoptosis induced by celastrol could be suppressed by Z-IETD-FMK and Z-LEHD-FMK, the respective caspase-8 and caspase-9 inhibitor. In addition, western blot analysis revealed a significant augmentation in the protein expression of Bax and attenuation in Bcl-2, suggesting that the celastrol-induced apoptosis acts through both death receptor and mitochondrial pathways. Moreover, western blot analysis on the expression of Rel/NF-κB demonstrated that the celastrol-mediated apoptosis on HaCaT cells was associated with the inhibition of the NF-κB pathway. Taken together, the present project has for the first time identified celastrol as a naturally occurring compound with potent apoptogenic action on cultured human keratinocytes, rendering it a promising candidate for further development into an anti-psoriatic agent.

CuO/CeO2 catalysts were prepared via the impregnation of CeO2 nano-particles derived from sol-gel method with Cu(NO3)2 solution. The samples were examined using the methods of XRD, H2-TPR, and XPS. The catalytic properties of the catalysts for CO oxidation were studied by means of a microreactor-GC system.

An aluminium isopolycation heteropolyanion salt with moderate surface area has been prepared and characterized with BET, IR, DTA/TGA, CV and elemental analysis. This solid was used as a catalyst for aromatic alkene epoxidation.

Arbutin was synthesized from glucose by two-step reaction below: (a) 2,3,4,6-tetra-O-acetyl-alpha-D-glucosyl chloride or bromide was prepared by glucose and acetyl halide (chloride or bromide). (b) 2,3,4,6-tetra-O-acetyl-alpha-D-glucosyl halide (Cl, Br) reacted with hydroquinone, methanol as solvent at pH=9.5-10.0.

The title compound, 2-[1,2,3,4,4a,4b,5,6,7,8,8a,9-dodecahydro-7-hydroxy-4b,8,8-trimethylphenanthren-2-yl]propenoic acid, C20H30O3, is a naturally occurring diterpenoid which was isolated from Rabdosia macrocalyx. The hydroxy and carboxy groups, which are located at the two ends of the molecule, both serve as simultaneous hydrogen-bond donors and acceptors. Two intermolecular O-H...O hydrogen bonds are present and link each molecule to four neighbours, thus forming an extensive hydrogen-bond network within the crystal.

Eighteen spleens derived from patients with hairy cell leukemia (HCL) were analyzed by correlative scanning and transmission electron microscopy. In 15 of the cases, the white pulp areas were markedly decreased or absent when compared to normal spleens, although few hairy cells were observed within this region. In only one case did the white pulp appear normal. In all HCL cases, hairy cells were observed within normal, dilated, and abnormal sinuses. The abnormal sinuses contained hairy cells of typical morphology attached to other hairy cells, to endothelial lining, and to erythrocytes. The degree of sinus filling by hairy cells varied from loosely- to tightly-packed. Endothelial cells exhibiting degenerative changes, such as swelling with smooth surfaces and dilated intercellular spaces, were frequently seen. These results indicate that in addition to the previously described overcrowding of the spleen by hairy cells, the splenic tissue itself is considerably altered and sometimes severely damaged in patients with HCL.