Search

To investigate the effects of curcumin on the proliferation, apoptosis, and cell cycle of human acute myeloid leukemia cell line K562.MTT method was used to detect the proliferation inhibition of logarithmic growth phase human acute myeloid leukemia K562 cells, flow cytometry was used to detect the cell cycle, Annexin V-FITC was used to detect the apoptosis rate, and real-time fluorescent quantitative PCR and Western blot were used to detect the expression of Bax, BCL-2 and caspase-3 mRNA and protein, respectively.The inhibition rate of cell proliferation in curcumin 10, 20, and 40 μmol/L group for 24 h and 48 h were higher than that in the control group (curcumin 0 μmol/L), and the cell proliferation inhibition rate was concentration-time dependent (r=0.879, r=0.914). The proportion of GCurcumin can inhibit the proliferation of human acute myeloid leukemia cell line K562 cells, block the cell cycle at G姜黄素对人急性髓系白血病细胞株K562增殖、凋亡及细胞周期的影响.探讨姜黄素对人急性髓系白血病细胞株K562增殖、凋亡及细胞周期的影响。.取对数生长期人急性髓系白血病K562细胞，用MTT法测定细胞增殖抑制情况，流式细胞术检测细胞周期，Annexin V-FITC检测细胞凋亡率，实时荧光定量PCR法和Western blot分别检测Bax、BCL-2和Caspase-3 mRNA和蛋白的表达。.姜黄素10、20和40 μmol/L组培养24 h和48 h细胞增殖抑制率均高于对照组（姜黄素0 μmol/L），且细胞增殖抑制率呈浓度-时间依赖性（r=0.879，r=0.914）。姜黄素10、20和40 μmol/L组G姜黄素可抑制人急性髓系白血病细胞株K562细胞增殖，将细胞周期阻滞于G

To investigate the expression and correlation of miR-211, miR-155, and C-myc in acute T lymphocytic leukemia (T-ALL), aiming to provide evidence for the diagnosis and treatment.A total of 96 T-ALL patients who were diagnosed and treated in People's Hospital of Zhengzhou from June 2014 to June 2017 were selected, and 69 healthy volunteers who had a physical examination were selected as control group in the same period. Real-time fluorescent quantitative PCR (RT-PCR) was used to determine the expression levels of miR-211, miR-155, and C-myc in peripheral blood mononuclear cells in each group. Kaplan-Meier was used to analyze the survival of T-ALL patients and correlation of miR-211, miR-155, and C-myc with prognosis. Pearson correlation analysis was used to evaluate the correlation of miR-211, miR-155, and C-myc with disease risk.The expression levels of miR-211 mRNA, miR-155 mRNA, and C-myc mRNA in T-ALL group were higher than those in the control group (P0.01), those in non-remission group were higher than those in remission group (P0.01), and those in high-risk group were also higher than those in low-risk group and intermediate-risk group (P0.01). The survival time of T-ALL patients with low miR-211 expression was longer than that with high miR-211 expression (P0.01), that with low miR-155 expression was longer than that with high miR-155 expression (P0.01), and that with low C-myc expression was also longer than that with high C-myc expression (P0.01). The high expression of miR-211, miR-155, and C-myc was linearly positively correlated with high risk of disease (r=0.749, 0.781, 0.804).The expressions of miR-211, miR-155, and C-myc are up-regulated in T-ALL patients, closely related to prognosis, and linearly positively correlated with disease risk.急性T淋巴细胞白血病的miR-211、miR-155、C-myc表达水平及相关性研究.分析并探讨急性T淋巴细胞白血病（T-ALL）的miR-211、miR-155、C-myc表达及相关性，旨在为早期诊断及预后监测提供依据.选择2014年6月-2017年6月于郑州人民医院接受诊治的T-ALL患者96例，另选同期体检健康的志愿者69例为对照组，采用实时荧光定量PCR测定各组外周血单个核细胞中miR-211、miR-155、C-myc表达水平，通过Kaplan-Meier分析T-ALL患者生存情况及miR-211、miR-155和C-myc与预后的关系，Pearson相关分析评价miR-211、miR-155和C-myc与疾病危险度的相关性.T-ALL组miR-211 mRNA、miR-155 mRNA、C-myc mRNA表达水平均明显高于对照组（P0.01），未缓解组均明显高于缓解组（P0.01），高危组亦明显高于低危组和中危组（P0.01）。miR-211低表达患者生存时间明显长于高表达患者（P0.01），miR-155低表达患者生存时间明显长于高表达患者（P0.01），C-myc低表达患者生存时间亦明显长于高表达患者（P0.01）。miR-211、miR-155和C-myc高表达与疾病高危呈线性正相关(r=0.749、0.781、0.804).T-ALL患者miR-211、miR-155、C-myc表达上调，其表达水平与预后密切相关，且与疾病危险度呈线性正相关.

Carbon fiber reinforced plastic (CFRP) composites are extremely attractive in the manufacturing of structural and functional components in the aircraft manufacturing field due to their outstanding properties, such as good fatigue resistance, high specific stiffness/strength, and good shock absorption. However, because of their inherent anisotropy, low interlamination strength, and abrasive characteristics, CFRP composites are considered difficult-to-cut materials and are prone to generating serious hole defects, such as delamination, tearing, and burrs. The advanced longitudinal–torsional coupled ultrasonic vibration assisted drilling (LTC-UAD) method has a potential application for drilling CFRP composites. At present, LTC-UAD is mainly adopted for drilling metal materials and rarely for CFRP. Therefore, this study analyzes the kinematic characteristics and the influence of feed rate on the drilling performance of LTC-UAD. Experimental results indicate that LTC-UAD can reduce the thrust force by 39% compared to conventional drilling. Furthermore, LTC-UAD can decrease the delamination and burr factors and improve the surface quality of the hole wall. Thus, LTC-UAD is an applicable process method for drilling components made with CFRP composites.

The surface quality of tungsten heavy alloy parts has an important influence on its service performance. The accurate on-line prediction of surface roughness in ultra-precision cutting of tungsten heavy alloy has always been the difficulty of research. In this paper, the ultrasonic elliptical vibration cutting technology is used for ultra-precision machining of tungsten heavy alloy. Based on the idea of deep learning, the surface roughness is discretized, and the fitting problem in surface roughness is transformed into a classification problem. The generalization ability of the prediction model is improved by introducing batch standardization and Dropout. The relationship between the vibration signal and the surface roughness is established. Experimental results show that the model can achieve on-line prediction of cutting surface roughness. The prediction accuracy rate can be improved by more than 10% compared with the direct fitting method.

A ultrasonic elliptical vibration cutting (UEVC) technique, as an advanced cutting method, has been successfully applied to machine difficult-to-cut materials for the last decade. In this study, the mechanism of the elliptical vibration locus caused by the “asymmetric structure” on the horn was analyzed theoretically first, and the corresponding relationship between the degree of asymmetry and the elliptical vibration locus was determined based on the finite element method (FEM). Then, an efficient single-excitation UEVC device with “asymmetric structure” was developed and optimized. The resonant frequency of the device was 40.8 kHz, and the amplitude reached 14 µm, which effectively broke the limitation of cutting speed in UEVC. Finally, the UEVC device’s performance was tested, and the advantages in improving the tungsten alloy surface quality and reducing diamond cutting tool wear validated the technical capability and principle of the proposed device.

In vitro assays of enzymes involved in the biosynthesis of maleidrides from polyketides in fungi were performed. The results show that the enzymes are closely related to primary metabolism enzymes of the citric acid cycle in terms of stereochemical preferences, but with an expanded substrate selectivity. A key citrate synthase can react both saturated and unsaturated acyl CoA substrates to give solely anti substituted citrates. This undergoes anti-dehydration to afford an unsaturated precursor which is cyclised in vitro by ketosteroid-isomerase-like enzymes to give byssochlamic acid.

In this paper, we propose a map which connects nucleons bound in nuclei and Ising spins in Ising model. This proposal is based on the fact that the description of states of nucleons and Ising spins could share the same type of observables. We present a nuclear model as a correspondence to an explicit modified Ising model and qualitatively confirm the correctness of this map by simulation on a two-dimensional square lattice. This map would help us understand the profound connections between different physical systems., Comment: 8 pages, 6 figures

Das Hauptaugenmerk der vorgestellten Arbeit lag auf dem Verständnis des Biosynthesewegs von Viridofungin, der Untersuchung der enzymatischen Eigenschaften der Schlüsselenzyme aus dem Byssochlaminsäure-Weg und der Entwicklung der PKS von Tenellin. In einer kombination aus genetischen und chemischen experimenten Ansatz wurden der Biosyntheseweg von Viridiofungin und die Funktionen von Enzymen aus dem Byssochlaminsäure-Weg sowie die Programmierung des Tenellin-PKS (TENS) -Systems aufgeklärt. Das Trichoderma-virid MF5628 wurde zunächst durch Illumina- und Oxford-Nanoporen-Sequenzierung genomsequenziert. Es wurde unter Verwendung einer Kombination aus gezielter Gen-Knockout- und RNA-Interference-basierter Stummschaltung im nativen Organismus ein neuer, nicht veröffentlicht Biosyntheseweg identifiziert, an dem eine tRNA-Ligase beteiligt ist. Es wurde festgestellt, dass ein Citrat-Synthase-ähnliches Enzym und ein tRNA-Ligase-ähnliches Enzym für die Biosynthese von Viridiofungin essentiell sind. Die Biosynthese von Byssochlaminsäure wurde durch Proteinexpression und in-vitro-Studie enukleiert. Eine Hydrolase, Citrat-Synthase, zwei 2-Methylcitrat-Dehydratase, zwei KSIs und zwei PEBPs-Proteine wurden in E. coli und Hefe exprimiert. Während der Maleinsäureanhydridmonomer Biosynthese kann eine Hydrolase die Hexaketidform vom ACP hydrolysieren. Die Citrat-Synthase kann Hexaketid-CoA und Oxalacetat als Substrat verwenden, um (2S, 3R) -Citrat zu bilden. 2-Methylcitrat-Dehydratase nimmt (2S, 3R) -Citrat-Diasteroisomer als Substrat, um ein 2, 3-Alken im Produkt zu bilden, und das Produkt kann ein spontan cyclisiertes Maleinsäureanhydridmonomer bilden. Zwei KSI verwenden schließlich Maleinsäureanhydrid-monomer, um das dimerisierte Produkt Byssochlaminsäure zu bilden. PEBP-Enzyme sind nicht der Katalyse der Dimerisierung beteiligt. Basierend auf dem KR-Domain-Swap-Experiment mit TenS wurde die Kettenlängenprogrammierung in TenS aufgeklärt. Sechs KR-Domänen-Subfragmente, die mit den homologen Fragmenten der Hexaketid-Desmethylbassianin-Synthase (DMBS) und drei mit der Heptaketid-Militarinon-Synthase (MILS) ausgetauscht wurden, führten zur Synthese unterschiedlicher Kettenlängen von Polyketid-Produkten. Insbesondere der MILS KR-Domänenaustausch führte zur Synthese von Penta, Hexa und Heptaketiden. Die Ergebnisse dieser und vorherger Experimente in unserer Gruppe werden einbezogen, indem die Existenz einer Konkurrenz zwischen den CMeT- und KR-Domänen berücksichtigt wird.

Improvement in the management of biofouling on ship hull can help to enhance the operational performance of ships and reduce cost of shipping. It can also effectively minimize the environmental impact e.g. spread of invasive aquatic species of international shipping. The operation of the newly developed hydroblasting cleanup system indicates that angles and types of nozzles have apparent effects on the effectiveness of biofouling removal. With a distance of 6 mm from nozzle tip to specimen surface, the biofouling removal rates were 41%, 59%, and 71% for 25° flat, 65° flat, and rotating jet, respectively. The results obtained in the study demonstrate that the growth of biofilms can be interrupted effectively by using the developed system. We determined the extent to which the proposed technology can be used to prevent the buildup of biofouling on international vessels, to reduce the global transfer of nonindigenous species, and to contribute to the future development of useful solutions. We suggest that future studies use this cleaning system periodically while monitoring the status of biofouling to determine the effectiveness of the interference. The results can also be used to establish parameters (e.g., cleaning cycle duration) for a strategic plan.

This study consists of the partial result of the High Scope Plan "The Study of the Teaching of Dig-itized Project-Based Learning in the Atayal Indige-nous High School" of the Ministry of Science and Technology, ROC. This is a quantitative study. The participants were 24 indigenous high school students in Yilan. Through the teaching procedures, the students' visual design abilities of cultural and creative goods in 3D printing experience were studied. The students had best performance in "novelty" and "singularity".

A complete three-dimensional finite difference scheme has been developed and used to analyze the nonlinear hydrodynamic pressures on arch dam during earthquakes. Both free-surface waves and nonlinear convective acceleration are included in the analysis. Various dam shapes and reservoir banks were studied and the characteristic of nonlinear contribution due to curved geometry and free-surface waves are discussed. Numerical experiments have been made to determine the desirable mesh size arrangements and time increments. The effects of surface wave and convective acceleration on hydrodynamic pressure could augment the hydrodynamic pressure to 10% larger than that of a linear analysis. For an earthquake with large ground displacement, a large rise of the water surface could probably happen and be a severe threat to human safety in recreational areas and even cause overflow to affect the safe operation of the arch dam. An empirical formula is given to predict approximate hydrodynamic force.

The composites of Fe/Al2O3 gradient coatings on steel substrate were prepared by spraying and sol-gel method, and the microstructure and performances of the composites were analyzed. The results show that the adhesion strength of Fe/Al2O3 gradient coatings with FeAlNi transitional layers reaches 25.3MPa when the sintering temperature is 1220°C, and the surface hardness of coatings is four times higher than that of steel substrate. The coatings are mainly composed of α-Al2O3, AlFeO3 and NiFe2O4. There is no obvious hole or macro-interface, while some organization similar to the branch appears in the coatings. The bonding of Fe/Al2O3 gradient coatings and steel substrate mainly depends on adsorption, diffusion and chemical combination.