Star pattern recognition method based on neural network

Star sensor is a sensitive instrument for determina-tion of a spacecraft attitude with high accuracy. The in-strument can determine the spacecraft 3-axis attitude through the recognition of observed stars. It measures star magnitude and star coordinates in the spacecraft coordi-nate frame. The measures are then compared with a refer-ence star catalog to obtain the attitude information of the spacecraft[1,2]. The purpose of star pattern recognition is to identify the corresponding relations bet…     

Pinacidil,a K<Subscript>atp</Subscript> channel opener,identified as a novel agonist for TRPA1

The transient receptor potential Ankyrin 1(TRPA1) cation channel is activated by various pungent and irritant compounds,and it also mediates the perception of noxious cold.Identification of different agonists for this channel is important for understanding its activation mechanism.Therefore,a screen for novel TRPA1 agonists was performed using an agonist-induced calcium influx assay.Out of 90 compounds screened,pinacidil was identified as a novel agonist for this channel.Pinacidil is a known opener of the K atp channel,for which it has an EC50 value of 1-3 μmol/L.In comparison,the EC50 value of pinacidil for TRPA1 is relatively high(260 μmol/L).Recombinant HEK-TRPA1 cells did not respond to P1075,another K atp channel opener,suggesting that the effect of pinacidil on TRPA1 was highly specific.Further studies revealed that the agonist activity of pinacidil could be blocked by the TRP channel inhibitors,ruthenium red and HC-030031.Using glutathione(GSH) and site-specific mutagenesis,we demonstrated that pinacidil could activate TRPA1 by covalent modification of the critical amino acids C619,C639 and C663 in the N-terminus of TRPA1.     

Accurate determination of the plate model based on CCD images with different orientations

The images of the open cluster NGC2168 are taken using the newly-fitted 2k×2k CCD attached to the 1-m telescope at the Yun-nan Observatory with two different orientations. After the catalogue position of a star from UCAC2 is compared with its corresponding measured position, a surprising result shows that a small field of view (about 7′×7′) exhibits an obvious distortion. Spe-cifically, the polynomial between the standard coordinate (ξ,η) and its corresponding measured one (x,y) for a star in each field of view has significant terms as high as 4th order. Accordingly, the positional measurement accuracy of a bright UCAC2 star can be derived as well as ~7 mas in each direction (60 s of exposure time and near the zenith). This new finding would be important for a CCD image to deliver a highly accurate position in its whole field of view.     

Speciation of iron in atmospheric particulate matter by EXAFS

In the atmospheric particulate matter (PM), fractions with a particle size of less than 10 μm (PM10) or evenless than 2.5 μm (PM2.5) in aerodynamic diameter can be inhaled into human body and cause serious health problems[1,2]. The influence of the PM on health is not only related to elemental concentrations, but also to its chemical speciation. The study on elemental speciation in atmospheric PM is significant for evaluating toxicity of PM and providing information about the formation a…     

The Reverse Petty Projection Inequality

It is proved that if K is an origin-symmetric convex body in R~2 and Π*K is the polar projection body of K,then the volumes of K and Π*K satisfy the inequality V(K)V(Π*K)≥2 with equality if K is a parallelogram.     

On the measurement of slip length for liquid flow over super-hydrophobic surface

To design a surface with large slip or larger drag reduction is a pop issue in the fields of liquid transporting and body swimming. In this context, it is a crucial problem to measure the slip length for these surfaces. Here we propose a novel method by using rheometer for this objective. This method is implemented by designing the distribution of the super-hydrophobic area on the sample. Using this method, a slip length of 40 μm for 70 wt% glycerin flow over a super-hydrophobic surface with stripe structure （the period, width and height of ridges are 150 μm, 40 μm and 65 μm, respectively） is measured. The result shows that the slip length measured using this method is in good agreement with former results measured by other methods. This method is fit for measuring the slip length of super-hydrophobic surface whose structure ranges from microto nano-scale.     

Effects of ytterbium on outward K<Superscript>+</Superscript> currents in NIH3T3 cell

Using the whole cell patch-clamp technique, we observed the outward K+ currents and studied for the first time the effects of Yb3+ on the currents and kinetics of activation and inactivation in non-excitable NIH3T3 cell. Our results show that the outward K+ currents were promoted with increasing concentration of Ca2+ in pipette solution and saturated at the concentration of 100 μmol/L Ca2+. Yb3+ in bath solution inhibited the currents in a concentration-dependent manner. At the concentration of 1 μmol/L, Yb...     

Conjugated 8-Hydroxylquinoline-Based Fluorescent Chemosensor for Zn~(2+) and Cd~(2+) and Bioimaging Application in Living Cells

A conjugated 8-hydroxyquinoline( 8-HQ)-based fluorescent chemosensor( 1) for Zinc ion( Zn~(2+)) and Cadmium ion( Cd~(2+)) was developed in aqueous solution and used for Zinc ion living cells bioimaging. The probe 1 was weakly fluorescent,but displayed a strong fluorescence at 580 nm with a large Stokes shift of150 nm in the presence of Zn~(2+) or Cd~(2+). This probe allows the detections of Zn~(2+) in the range of 0. 8-10 μmol/L and Cd~(2+) in the range of 0. 8-8 μmol/L,with the limit of detections of 0. 2 and 0. 6μmol/L for Zn~(2+) and Cd~(2+),respectively. The present probe was successfully used for fluorescence bioimaging of Zn~(2+) or Cd~(2+) in the living cells.     

Apoptosis induced by （DIPP-L-Leu）2-L-Lys-OCH3 in K562 cells

Apoptosis as a mechanism of deleting cells from tissues plays an important role in physiological and varieties of pathological situations, especially cancer conditions. In order to search for tumor cells apoptosis inducers, the inhibition effects on K562 cells of N-phosphoryl dipeptide methyl esters were studied by MTT assays, and (DIPP-L-Leu)2-L-Lys-OCH3 was the compound which had the best activity. From the studies of the typical apoptotic morphologic changes, DNA agarose gel electrophoresis, and flow cytometry analysis, it could be concluded that (DIPP-L-Leu)2-L-Lys-OCH3 could induce apoptosis of K562 cells in a dose-dependent manner, and the IC50 was 22.66 μmol/L according to MTT assays.     

Lead removal from aqueous solution by employing natural brucite

The effect and mechanism of the removal of Pb2+ from an aqueous solution by using brucite as the adsorbent were studied.It was revealed that the increase in pH of brucite suspension, as a result of the release of magnesium hydroxide into the suspension,leads to a sharp rise of the adsorption amount of Pb2+ on brucite. The synergism of buffering and adsorption capacities of brucite is responsible for the removal of Pb2+ from the aqueous solution. The coexistence of Cu2+ with Pb2+ causes a decrease of their adsorption on brucite due to a competition for surface sites and brucite exhibits a higher adsorption capacity for Pb2+ than for Cu2+. The percentage adsorption of Pb2+ on brucite could reach 96.38%, 97.20% and 94.09% respectively with the initial pH of the suspension pH_i = 1.76 (initial Pb2+ concentration [Pb2+]_i = 20 μmol/L), 1.82 ([Pb2+]_i = 100 μmol/L) and 1.84 ([Pb2+]_i = 500 μmol/L). It was concluded that brucite is a very efficient mineral adsorbent for Pb2+ removal from polluted acidic water.     

Preparation and bioactivity of sol-gel macroporous bioactive glass

Bioactive glass is well known for its ability of bone regeneration, and sol-gel bioactive glass has many advantages compared with melt-derived bioactive glass. 3-D scaffold prepared by the sol-gel method is a promising substrate material for bone tissue engineering and large-scale bone repair. Porous sol-gel glass in the CaO-SiO₂-P₂0₅ system with macropores larger than 100 μm was prepared by the addition of stearic acid as a pore former. The diameter of the pore created by the pore former varied from 100 to 300 μm. The formation of a hydroxyapatite layer on the glass was analyzed by studying the surface of the porous glass by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman spectra after they had been immersed in simulated body fluid (SBF) for some time, and the porous glass shows good bioactivity.     

Microstructure,crystalline phase and electrical properties of Li_(0.06)(Na_(0.5)K_(0.5))_(0.94)Nb_(1-2x/5)Mg_xO_3 lead-free piezoelectric ceramics

MgO-modified Li0.06(Na0.5K0.5)0.94NbO3(L6NKN) lead-free piezoelectric ceramics were synthesized by normal sintering at a relatively low temperature of 1000°C.The crystalline phase,microstructure,and electrical properties of the ceramics were investigated with a special emphasis on the influence of MgO content.The addition of MgO effectively improves the sinterability of the L6NKN ceramics.X-ray diffraction analysis indicates that the morphotropic phase boundary(MPB) separating orthorhombic and tetragonal phases for the ceramics lies in the range of Mg doping content(x) from 0.3at% to 0.7at%.High electrical properties of the piezoelectric constant(d33=238 pC/N),planar electromechanical coupling coefficient(kp=41.5%),relative dielectric constant(εr=905),and remanent polarization(Pr=38.3 μC/cm2) are obtained from the specimen with x=0.5at%,which suggests that the Li0.06(Na0.5K0.5)0.94Nb(1-2x/5)MgxO3(x=0.5at%) ceramic is a promising lead-free piezoelectric material.     

Investigation on apoptosis of neuronal cells induced by Amyloid beta-Protein

Objective: To construct a PC12 cell strain with neuronal differentiation, and observe the apoptosis and pro-liferation activity effects induced these cells by Amyloid beta-Protein (Aβ3-43). Methods: 1) PC12 cells in logarithmic growth phase were subcultured for 24 h. After the culture fluid was changed, the cells were treated with Rat-β-NGF and cultured for 9 days. 2) Neuronal differentiation of PC 12 cells in logarithmic growth phase were divided into four groups:control group (0), experimental group (1), experimental group (2) and experimental group (3). The concentrations of Aβ in the four groups were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μmol/L, respectively. The cells were harvested at 24, 48 and 72 h later and stained with AnnexinV-FITC/PI after centrifugation and washing. Then flow cytometry was conducted to examine the apoptosis percentage. 3) NGF-induced PC12 cells were selected and Aβ with different concentrations was added. The final concentrations of Aβ were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μmol/L, respectively. After the cells were incubated in an atmosphere of 5% CO2 at 37 ℃ in an incubator for 72 h, the OD values were examined. Results: 1)Neuronal differentiated PC12 cell lines were successfully established. 2) Flow cytometric examination indicated that Aβ(1.25, 2.5, and 5.0 μmol/L) could effectively induce apoptosis of neuronal-differented cells at the 24 h, 48 h and 72 h time points. 3) Aβ (0-5.00 μmol/L) had no obvious effect on proliferation or restraining of the neuronal differentiation of the PC 12 cells after a 72 h interacting process. Conclusion: This investigation revealed successful neuronal differentiation of the PC12 cell strain. The induction of apoptosis of the neurocytes by various concentrations of Aβ was observed and the in-fluence of Aβ on induced proliferation of PC 12 cells by Rat-β-NGF was revealed. This study may provide basis for future research on the molecular cure of AD and interdiction of AD evolution.     

CHANGES IN BODY WEIGHT AND ORGAN WEIGHTS OF THE HEDGEHOG IN HIBERNATION AND IN FASTING

Under the circumstances of uninterrupted deep hibernation for periods cf three and half months in open air quarters, the body weight loss of the hedgehog proceeds at a rate of 1.04 g p3r day, or 1.37 g per day per kg.During experimental fasting, the body weight suffers at first a rapid decrease for 1-2 days and then a more gradual diminution at a uniform rate, followed sooner or later by a terminating phase of a slow decline concurrent with a fall in body temperature to the level of the ambient temperature. The duration of fasting compatible to life varies with the initial body weight, a few days for the ordinary hedgehogs and a month or more for the exceptionally fat ones. During the period of uniform decrease, the rate of body weight loss is 11-15 g per day, slightly more in the samll animals. However, when the rate of loss is expressed in terms of g per day per kg body weight, it varies from 9 g in the very fat animals of about 1300 g to as much as 54 g in the small ones between 200 and 300 g.In gene     

Electrochromics for Energy Efficiency and Indoor Comfort

1 Results This paper aims at (ⅰ) giving a background and justification for electrochromics (EC) research,(ⅱ) providing a perspective on ongoing research and development,and (ⅲ) attempting to point towards the future importance of EC technology.As to the “whys“,the current precarious energy scene,with growing concerns for the effects of global warming and supply shortage,call for new measures for energy efficiency.An energy guzzler,the significance of which is becoming more and more important,is air cond...     

Human Body Modeling and Posture Simulating Based on 3D Surface Scan Data

This paper presents a new approach for modeling the human body by considering the motion state and the shape of whole body. The body model consists of a skeleton kinematic model and a surface model. The former is used to determine the posture of the body, and the latter is used to generate the body shape according to the given posture. The body surface is reconstructed with multi-segment B-spline surfaces based on the 3D scan data from a real human body. Using only a few joints parameters and the original surface scan data, the various body postures and the shape can be generated easily. The model has a strong potential of being used for ergonomic design, garment design, virtual reality environment, as well as creating human animation, etc.     

Comprehensive test stand for high-intensity cyclotron development

A comprehensive test stand for high-intensity cyclotron development,a 10 MeV 430 μA cyclotron,has been successfully constructed at China Institute of Atomic Energy (CIAE) for the experimental verification of the viability of a 100 MeV high-intensity cyclotron (CYCIAE-100) being constructed at CIAE.The verification includes the overall design technology,detail design and engineering technology for the crucial parts of the machine,e.g.main magnet and beam diagnostics.It will also pave the way for future enhancement of the beam intensity.The test stand consists of a H-ion source,axial injection system,central region,main magnet and coil,RF resonator,stripping extraction,and auxiliary systems,which include the RF power amplifier,high voltage and DC power supplies,electric apparatus,beam diagnostics,control,vacuum,water cooling,pneumatic system,and safety interlock.This paper presents the work regarding the design and sub-system development of the test sand,and the results of the beam commissioning of the machine.     

Inequalities for the radial p-th mean bodies

In this paper, we establish an inequality for the volumes of K and its radial p-th mean body R_pK by L_p-dual mixed volume. Further, the Shephard-type problem and a monotonitic inequality of R_pK are shown when p>0 .     

Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma

Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated, regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition： concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 ℃, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 μg/g and 1516.0 μg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice.     

Determination of Selenium in Water by Vortex-Assisted Cloud-Point Extraction Combination with Fluorescence Detection

A simple vortex-assisted cloud-point extraction( VA-CPE) method combined with the fluorescence( FL)strategy was developed to extract and determine inorganic Se( IV) in environmental water. Toluene was used as an extraction reagent,and Se( VI) was reduced to Se( IV) by subjecting its solution in 4 mol/L HCl to microwave heating for generating a yellow piazselenol complex using 3,3'-diaminobenzidine( DAB) and Se( IV). The concentration of the complex exhibited an excellent linear relation with the FL at 560 nm with an excitation wavelength of 420 nm. In addition,the effects of the toluene volume,p H,and VACPE parameters were investigated and the interference from coexisting ions was also studied. This method was successfully applied to determine the concentration selenium in environmental water samples with a detection limit of0.05 μg/L in the line range from 0.50 μg/L to 50.00 μg/L.