Precisely-controlled synthesis of mesoporous Pt particles and films with various nanoarchitectures

制度:新 ; 報告番号:甲3721号 ; 学位の種類:博士(工学) ; 授与年月日:2012/9/15 ; 早大学位記番号:新6091Waseda Universit

Enhanced Microwave Absorption Properties of α-Fe2O3-Filled Ordered Mesoporous Carbon Nanorods

A novel kind of α-Fe2O3-filled ordered mesoporous carbon nanorods has been synthesized by a facial hydrothermal method. Compared with dendritic α-Fe2O3 micropines, both a broader effective absorption range—from 10.5 GHz to 16.5 GHz with reflection loss (RL) less than −10 dB—and a thinner matching thickness of 2.0 mm have been achieved in the frequency range 2–18 GHz. The enhanced microwave absorption properties evaluated by the RL are attributed to the enhanced dielectric loss resulting from the intrinsic physical properties and special structures

Synchronous MDADT-Based Fuzzy Adaptive Tracking Control for Switched Multiagent Systems via Modified Self-Triggered Mechanism

In this paper, a self-triggered fuzzy adaptive switched control strategy is proposed to address the synchronous tracking issue in switched stochastic multiagent systems (MASs) based on mode-dependent average dwell-time (MDADT) method. Firstly, a synchronous slow switching mechanism is considered in switched stochastic MASs and realized through a class of designed switching signals under MDADT property. By utilizing the information of both specific agents under switching dynamics and observers with switching features, the synchronous switching signals are designed, which reduces the design complexity. Then, a switched state observer via a switching-related output mask is proposed. The information of agents and their preserved neighbors is utilized to construct the observer and the observation performance of states is improved. Moreover, a modified self- triggered mechanism is designed to improve control performance via proposing auxiliary function. Finally, by analysing the re- lationship between the synchronous switching problem and the different switching features of the followers, the synchronous slow switching mechanism based on MDADT is obtained. Meanwhile, the designed self-triggered controller can guarantee that all signals of the closed-loop system are ultimately bounded under the switching signals. The effectiveness of the designed control method can be verified by some simulation results

Epigenetics in ovarian cancer: premise, properties, and perspectives.

Malignant ovarian tumors bear the highest mortality rate among all gynecological cancers. Both late tumor diagnosis and tolerance to available chemical therapy increase patient mortality. Therefore, it is both urgent and important to identify biomarkers facilitating early identification and novel agents preventing recurrence. Accumulating evidence demonstrates that epigenetic aberrations (particularly histone modifications) are crucial in tumor initiation and development. Histone acetylation and methylation are respectively regulated by acetyltransferases-deacetylases and methyltransferases-demethylases, both of which are implicated in ovarian cancer pathogenesis. In this review, we summarize the most recent discoveries pertaining to ovarian cancer development arising from the imbalance of histone acetylation and methylation, and provide insight into novel therapeutic interventions for the treatment of ovarian carcinoma

Selection of the Composition with High Glass Forming Ability in Zr-Cu-Ni-Al Bulk Metallic Glasses

Three new Zr-Cu-Ni-Al bulk metallic glasses were developed through appropriate mixing of three binary eutectics Zr38.2Cu61.8, Zr51Al49, and Zr64Ni36. By suppressing solidification of competing crystalline phases, a new glass forming alloy Zr51Cu24.22Ni14.06Al10.72 with the critical diameter of up to 10 mm is obtained

Hypoxia-inducible transcription factor-1α promotes hypoxia-induced A549 apoptosis via a mechanism that involves the glycolysis pathway

BACKGROUND: Hypoxia-inducible transcription factor-1α (HIF-1α), which plays an important role in controlling the hypoxia-induced glycolysis pathway, is a "master" gene in the tissue hypoxia response during tumor development. However, its role in the apoptosis of non-small cell lung cancer remains unknown. Here, we have studied the effects of HIF-1α on apoptosis by modulating HIF-1α gene expression in A549 cells through both siRNA knock-down and over-expression. METHODS: A549 cells were transfected with a HIF-1α siRNA plasmid or a HIF-1α expression vector. Transfected cells were exposed to a normoxic or hypoxic environment in the presence or absence of 25 mM HEPES and 2-deoxyglucose (2-DG) (5 mM). The expression of three key genes of the glycolysis pathway, glucose transporter type 1(GLUT1), phosphoglycerate kinase 1(PGK1), and hexokinase 1(HK1), were measured using real-time RT-PCR. Glycolysis was monitored by measuring changes of pH and lactate concentration in the culture medium. Apoptosis was detected by TUNEL assay and flow cytometry. RESULTS: Knocking down expression of HIF-1α inhibited the glycolysis pathway, increased the pH of the culture medium, and protected the cells from hypoxia-induced apoptosis. In contrast, over-expression of HIF-1α accelerated glycolysis in A549 cells, decreased the pH of the culture medium, and enhanced hypoxia-induced apoptosis. These effects of HIF-1α on glycolysis, pH of the medium, and apoptosis were reversed by treatment with the glycolytic inhibitor, 2-DG. Apoptosis induced by HIF-1α over-expression was partially inhibited by increasing the buffering capacity of the culture medium by adding HEPES. CONCLUSION: During hypoxia in A549 cells, HIF-1α promotes activity of the glycolysis pathway and decreases the pH of the culture medium, resulting in increased cellular apoptosis

MeJA regulates the accumulation of baicalein and other 4’-hydroxyflavones during the hollowed root development in Scutellaria baicalensis

The dried roots of Scutellaria baicalensis are important traditional Chinese medicine used to treat liver and lung inflammation. An anomalous structure, hollowed root, was discovered in perennial cultivated Scutellaria baicalensis. The presence of the hollow may change the contents of bioactive metabolites, such as baicalein, and other 4’-hydroxyflavones in Scutellaria baicalensis roots, but the relationship between the hollowed root and bioactive metabolite contents is poorly understood. In this study, we identified the anatomical structure of the hollowed root and detected differentially accumulating flavonoid metabolites and enzymes related to 4’-hydroxyflavone biosynthesis in 3-year-old roots with a hollow. We confirmed that methyl jasmonate (MeJA) induced the accumulation of 4’-hydroxyflavones and the expression of enzymes related to 4’-hydroxyflavone biosynthesis in hydroponically cultured Scutellaria baicalensis roots. The development of the hollowed root were divided into 4 stages. The 4’-hydroxyflavone contents and expression of enzymes related to 4’-hydroxyflavone biosynthesis increased synchronously with the content of MeJA during the development of hollowed root. Pathogen and programed-cell-death related genes were induced during hollowed root development. Taken together, our results provide novel insight into the importance of MeJA in the development of hollowed root and the accumulation of 4’-hydroxyflavones in Scutellaria baicalensis roots. Our results suggest that a pathogen and senescence are the two major causes for the development of hollowed root in Scutellaria baicalensis roots

Hydrological modeling in the Manas River Basin using soil and water assessment tool driven by CMADS

Hidrološka simulacija u meteorološki neispitanim područjima oduvijek je težak problem u proučavanju atmosferskih i hidroloških odnosa; to je također jedan od važnih faktora koji ograničavaju razvoj modela i spoznaju o izvoru vode u porječju. U svrhu analize atmosferskih i hidroloških odnosa; u radu se daje kvantitativna procjena promjene vodotokova u porječjima prekrivenim ledenjacima i snijegom, te je izabrano porječje rijeke Manas (Manas River Basin - MRB) u Kini kao tipično područje istraživanja u svrhu provjere prilagodljivosti meteoroloških podataka u Kini (China Meteorological Assimilation Driving Datasets) – CMADS, za model alata za procjenu tla i vode - Soil and Water Assessment Tool model (SWAT). Taj se model prvenstveno koristio za simulaciju izvora vode, a zatim smo ga kalibrirali s podacima CMADS-a, lokalizirali u porječje rijeke Manas (MRB), Kina, te konačno kalibrirali simulirano oticanje s dobivenim podacima SWAT-CUP (SWAT Calibration and Uncertainty Programs). Uz to, u ovo je istraživanje također uključena analiza osjetljivosti parametara te ocjena i kalibriranje parametara. Rezultati su pokazali da se modelom SWAT može dobro reproducirati proces oticanja vode na dva položaja istraživanog područja (Kenswat i Hongshanzui) primjenom podataka iz CMADS-a. Simulacija se pokazala uspješnom na osnovu podataka od mjesec dana na oba položaja gdje su R2 = (0,556÷0,999) i NSE = (0,937÷0,998), i dala zadovoljavajuće rezultate kod R2 = (0,927÷0,993) i NSE = (0,836÷0,997). Naše istraživanje pokazuje da se modelom SWAT mogu dobiti zadovoljavajući rezultati kalibriranjem parametara u područjima s visokim dotokom vode s vodenjaka. Uz to, CMADS može osigurati potrebne meteorološke podatke za SWAT simulacije i pomoći kod kalibriranja parametara i analize prikupljenih podataka s površine.Hydrological simulation in meteorological ungauged areas has always been a difficult problem for the study on atmospheric and hydrological coupling; meanwhile, it is also one of the important factors that restrict model development and basin water resource knowledge. To analyze the mechanism of atmospheric and hydrological coupling, this study quantitatively evaluated water cycle situation in basins covered with glaciers and snow, and chose the Manas River Basin (MRB) in China as the typical research area to verify the adaptability of the China Meteorological Assimilation Driving Datasets for the Soil and Water Assessment Tool model (CMADS). The SWAT model was firstly built to simulate water resources, then we calibrated the model with CMADS dataset and started localization in the Manas River Basin (MRB), China, and finally calibrated simulated runoff with observed data SWAT-CUP (SWAT Calibration and Uncertainty Programs). In addition, parameter sensitivity analysis, and parameter calibration and validation were also included in the present study. Results showed that the SWAT model could well reproduce the runoff process of two stations (Kenswat and Hongshanzui) in the research area by using data from CMADS. The simulation performed well on monthly scale in both stations, where R2 = (0,556÷0,999) and NSE = (0,937÷0,998), and also showed satisfactory effects, where R2 = (0,927÷0,993) and NSE = (0,836÷0,997).Our research suggests that the SWAT model can show satisfactory results through parameter calibration in areas with high glacial recharge rate. Moreover, CMADS can provide necessary meteorological data for SWAT simulations, and support parameter calibration and historical surface data analysis