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The heterodimeric structure of heterogeneous nuclear ribonucleoprotein C1/C2 dictates 1,25-dihydroxyvitamin D-directed transcriptional events in osteoblasts

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Bone Research 2014年第2期2卷 110-120页

作者： Thomas s Lisse Kanagasabai Vadivel s Paul Bajaj Rui Zhou Rene F Chun Martin Hewison John s Adams Department of Orthopaedic surgery and the Orthopaedic Hospital Research Center UCLA Los Angeles CA USA Department of Regenerative Biology and Medicine Mount Desert Island Biological Laboratory Bar Harbor ME USA

Heterogeneous nuclear ribonucleoprotein （hnRnP） C plays a key role in RnA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D （1,25（OH）2D） by functioning as a vitamin D response element-binding protein （VDRE-BP）. hnRnPC acts a tetramer of hnRnPC1 （huC1） and hnRnPC2 （huC2）, and organization of these subunits is critical to in vivo nucleic acid-binding. Overexpression of either huC1 or huC2 in human osteoblasts is sufficient to confer VDRE-BP suppression of 1,25（OH）2D-mediated transcription. However, huC1 or huC2 alone did not suppress 1,25（OH）2D-induced transcription in mouse osteoblastic cells. By contrast, overexpression of huC1 and huC2 in combination or transfection with a bone-specific polycistronic vector using a ＂self-cleaving＂ 2A peptide to co-express huC1/C2 suppressed 1,25D-mediated induction of osteoblast target gene expression. structural diversity of hnRnPC between human/nWPs and mouse/rat/rabbit/dog was investigated by analysis of sequence variations within the hnRnP CLZ domain. The predicted loss of distal helical function in hnRnPC from lower species provides an explanation for the altered interaction between huC1/C2 and their mouse counterparts. These data provide new evidence of a role for hnRnPC1/C2 in 1,25（OH）2D-driven gene expression, and further suggest that species-specific tetramerization is a crucial determinant of its actions as a regulator of VDR-directed transactivation.

关键词： gene The heterodimeric structure of heterogeneous nuclear ribonucleoprotein C1/C2 dictates 1,25-dihydroxyvitamin D-directed transcriptional events in osteoblasts Figure EcoRI

Model of tunnelling through periodic array of quantum dots in a magnetic field

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Chinese Physics B 2012年第11期21卷 412-415页

作者： I.Yu.Popov s.A.Osipov st.Petersburg national Research University of Information Technologies Mechanics and OpticsKronverkskiy49St.Petersburg 197101Russia

A two-dimensional periodic array of quantum dots with two laterally coupled leads in a magnetic field is considered. The model of electron transport through the system based on the theory of self-adjoint extensions of symmetric operators is suggested. We obtain the formula for the transmission coefficient and investigate its dependence on the magnetic field.

关键词： tunnelling nanostructure operator extension theory

The singular Kane Oscillator

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Chinese Physics Letters 2006年第1期23卷 10-12页

作者： Babayev A. M. Cakmaktepe s. Institute of Physics Azerbaijan Academy of Sciences 370143 Baku Department of Physics University of Suleyman Demirel Isparta 32260 Turkey

The energy spectrum of carriers in narrow band gap semiconductor nanocrystals are studied theoretically taking into account the nonparabolicity of charge carriers dispersion laws. The confinement potential of nanocrystals is approximated to be λγ^2 ＋ λ1γ^-2, and the dispersion laws are considered within the framework of the three-band Kane model.

关键词： DIRAC OsCILLATOR

Identification and classification of transient pulses observed in magnetometer array data by time-domain principal component analysis filtering

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Earthquake science 2017年第4期30卷 193-207页

作者： Karl n. Kappler Daniel D. schneider Laura s. MacLean Thomas E. Bleier Quake Finder Palo AltoCA 94306USA

A method for identification of pulsations in time series of magnetic field data which are simultaneously present in multiple channels of data at one or more sensor locations is described. Candidate pulsations of interest are first identified in geomagnetic time series by inspection. Time series of these ＂training events＂ are represented in matrix form and transpose-multiplied to generate time- domain covariance matrices. The ranked eigenvectors of this matrix are stored as a feature of the pulsation. In the second stage of the algorithm, a sliding window （approxi- mately the width of the training event） is moved across the vector-valued time-series comprising the channels on which the training event was observed. At each window position, the data covariance matrix and associated eigen- vectors are calculated. We compare the orientation of the dominant eigenvectors of the training data to those from the windowed data and flag windows where the dominant eigenvectors directions are similar. This was successful in automatically identifying pulses which share polarization and appear to be from the same source process. We apply the method to a case study of continuously sampled （50 Hz） data from six observatories, each equipped with three- component induction coil magnetometers. We examine a 90-day interval of data associated with a cluster of four observatories located within 50 km of napa, California, together with two remote reference stations-one 100 km to the north of the cluster and the other 350 km south. When the training data contains signals present in the remote reference observatories, we are reliably able to identify and extract global geomagnetic signals such as solar-generated noise. When training data contains pulsations only observed in the cluster of local observatories, we identify several types of non-plane wave signals having similar polarization.

关键词： Time series Magnetic fields Array data signal processing Principal component analysis

Recovery of coal particles from a tailing dam for environmental protection and economical beneficiations

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International Journal of Coal science & Technology 2018年第2期5卷 253-263页

作者： M. Asghari M. noaparast s. Z. shafaie s. Ghassa s. Chehreh Chelgani school of Mining Engineering University of TehranTehran 16846-13114 Iran Department of Electrical Engineering and Computer science University of Michigan Ann Arbor MI 48109 USA

Considerable amounts of coal particles are accumulated in the tailing dams of washing plants which can make serious environmental problems. Recovery of these particles from tailings has economically and environmentally several advantages. Maintaining natural resources and reducing discharges to the dams are the most important ones. This study was examined the possibility to recover coal particles from a tailing dam with 56.29% ash content by using series of processing techniques. For this purpose, gravity separation （jig, shaking table and spiral） and flotation tests were conducted to upgrade products. Based the optimum value of these processing methods, a flowsheet was designed to increase the rate of recovery for a wide range of coal particles. Results indicated that the designed circuit can recover over 90% of value coal particles and reduce ash content of product to less than 14%. These results can potentially be used for designing an industrial operation as a recycling plant and an appropriate instance for other areas to reduce the environmental issues of coal tailing dams.

关键词： Tailing dams Hazardous issues Jigging shaking table spiral Flotation

Cadmium sulfide thin films growth by chemical bath deposition

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Journal of semiconductors 2018年第3期39卷 50-56页

作者： s.Hariech M.s.Aida J.Bougdira M.Belmahi G.Medjahdi D.Genève n.Attaf H.Rinnert Thin films and Interfaces Laboratory Faculty of Sciences Mentouri University Department of physics Faculty of science King Abdulaziz University Jean Lamour Institute University of Lorraine

Cadmium sulfide（Cd s） thin films have been prepared by a simple technique such as chemical bath deposition（CBD）. A set of samples Cd s were deposited on glass substrates by varying the bath temperature from 55 to 75 °C at fixed deposition time（25 min） in order to investigate the effect of deposition temperature on Cd s films physical properties. The determination of growth activation energy suggests that at low temperature Cd s film growth is governed by the release of Cd^（2＋） ions in the solution. The structural characterization indicated that the Cd s films structure is cubic or hexagonal with preferential orientation along the direction（111） or（002）, respectively. The optical characterization indicated that the films have a fairly high transparency, which varies between55% and 80% in the visible range of the optical spectrum, the refractive index varies from 1.85 to 2.5 and the optical gap value of which can reach 2.2 e V. It can be suggested that these properties make these films perfectly suitable for their use as window film in thin films based solar cells.

关键词： thin films chemical bath cadmium sulfide solar cell

Humidity sensing properties of La^(3+) and K^+ co-doped Ti_(0.9)sn_(0.1)O_2 thin films

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Journal of Rare Earths 2011年第7期29卷 668-672页

作者： Mansoor Anbia s.E Moosavi Fard Research Laboratory of nanoporous Materials Faculty of Chemistry Iran University of Science and Technology Farjam Street Narmak Tehran 16846 Iran

The humidity sensing properties of La^3＋ and K^＋ co-doped Ti0.9sn0.1O2 thin films were investigated. The humidity sensitive thin films were prepared by sol-gel method on alumina substrates. The sensing behaviors of thin films were inspected at different sintering temperatures by constructing a humidity-impedance measuring system. It was found that the addition of rare earth ion La^3＋ and alkali ion K^＋ was beneficial for improving the humidity sensitive properties of the samples and La0.003K0.5Ti0.9sn0.1O2 sintered at 500 ℃ for 4 h showed the best humidity sensing properties. The impedance of this thin film decreased from 109 to 104 Ω with excellent linearity in the humidity range of 11%-95%. narrow hysteresis loop, prominent stability and high sensitivity were obtained. The effects of dopant con-tent and doping mechanism on humidity sensitivity were also discussed in terms of segregation of rare earth ions at grain boundaries and granularity of crystalline and influence of K^＋ on the decrease in the intrinsic resistance of the materials, and increase in the number of wa-ter adsorption sites.

关键词： humidity sensing thin film rare earths La^3+-doped K^+-doped Ti0.9sn0.1O2

Performance analysis of an integrated scheme in optical burst switching high-speed networks

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Chinese Optics Letters 2008年第4期6卷 244-247页

作者： Amit Kumar Garg R.s.Kaler school of Electronics and Communication Engineering shri Mata Vaishno Devi University(J and K) India school of Electronics and Communication Engineering Thapar University Patiala PunjabIndia

A new integrated scheme based on resource-reservation and adaptive network flow routing to alleviate contention in optical burst switching networks is proposed. The objective of the proposed scheme is to reduce the overall burst loss in the network and at the same time to avoid the packet out-of-sequence arrival problem. simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution schemes based on conventional routing. Through extensive simulations, it is shown that the proposed scheme not only provides significantly better burst loss performance than the basic equal proportion and hop-length based traffic routing algorithms, but also is void of any packet re-orderings.

关键词： rate node Performance analysis of an integrated scheme in optical burst switching high-speed networks OBs length

synthesis and luminescence characteristics of terbium(Ⅲ) activated nasrBO_3

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Journal of Rare Earths 2012年第9期30卷 856-859页

作者： P.A. nagpure s.K. Omanwar Department of Physics SGB Amravati University Amravati-444602 (M.S.) India

The thermoluminescence （TL） and photohmainescence （PL） properties of the phosphor nasrBO3：Tb3＋ were reported and discussed. The combustion technique was used for the synthesis of polycrystalline samples of nasrBO3：Th3＋. The TL glow curve of the compound had a simple structure with a single peak at 434 K. TL sensitivity of the phosphor was found to be more than that of （LiF：Mg,Cu,P）. The TL glow curve was studied as a function of concentration of dopant and dose of gamma ray irradiation. The kinetic parameters of the thermolumines- cence of nasrBO3： Tb3＋were calculated employing the peak shape method. The photoluminescence （PL） properties of Tb3＋ doped in nas- rBO3 were studied over the 200-400 nm excitation range. The excitation spectra of nasrBO3：Tb3＋ consisted of single narrow band peaking at about 236 nm. The emission spectra monitored at 236 nm excitation consisted of a series of sharp lines peaking at 489, 544, 586 and 622 nm corresponding to the 5D4→7Fj （j=3,4,5,6） transitions within the 4f8 configurations of Tb3＋.

关键词： thermoluminescence photoluminescence terbium nasrBO3 combustion synthesis rare earths