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Wyszukujesz frazę "Zhang, K." wg kryterium: Autor


Wyświetlanie 1-15 z 15
Tytuł:
Dynamic expression profile of DNA methyltransferases in rat testis development
Autorzy:
Xu, H.X.
Qin, J.Z.
Zhang, K.Y.
Zeng, W.X.
Powiązania:
https://bibliotekanauki.pl/articles/31635.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
DNA methyltransferases (Dnmts) are unique and perform specific functions during male germ cell development. To further characterize the significance of Dnmts in the events leading to production of spermatozoa, we investigated whether the expression patterns in Dnmt1, Dnmt3a, Dnmt3b and Dnmt3l were apparent in rat testes at different time points during development. The qRT-PCR results showed that expression levels of Dnmt3a and Dnmt3l were abundant before birth and were present at the highest levels in testes tissue at 18.5 days postcoitus (dpc), and gradually decreased from day 0 postpartum (dpp) to 90 dpp. Expression of Dnmt1 and Dnmt3b reached a peak after birth (P <0.01), and then gradually reduced until adulthood. Western blotting and immunolocalization analysis of Dnmt3a and Dnmt3b further confirmed the differential expression and localization of the two proteins during rat testis development. The dynamic expression profile of Dnmts implies specific and potentially nonredundant roles for each of these enzymes in the developing rat testis.
Źródło:
Polish Journal of Veterinary Sciences; 2015, 18, 3
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and numerical study of the uniaxial compressive stress-strain relationship of a rock mass with two parallel joints
Autorzy:
Xiong, L. X.
Yuan, H. Y.
Zhang, Y.
Zhang, K. F.
Li, J. B.
Powiązania:
https://bibliotekanauki.pl/articles/231076.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
masa skalna łączona
złącze równoległe
siła szczytowa
jointed rock mass
parallel joint
peak strength
Opis:
A “rock bridge”, defined as the closest distance between two joints in a rock mass, is an important feature affecting the jointed rock mass strength. Artificial jointed rock specimens with two parallel joint fractures were tested under uniaxial compression and numerical simulations were carried out to study the effects of the inclination of the rock bridge, the dip angle of the joint, rock bridge length, and the length of joints on the strength of the jointed rock mass. Research results show: (1) When the length of the joint fracture, the length of the rock bridge, and the inclination of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually increases as the inclination of the joint fracture increases from 0° to 90°. (2) When the length of the joint fracture, the length of the rock bridge, and the inclination of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen shows variations in trends with the inclination of the rock bridge increasing from 30° to 150° (3). In the case when the joint is angled from the vertical loading direction, when the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually decreases with an increasing length of joint fracture. When the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen does not show a clear trend with an increase of the length of the rock bridge.
Źródło:
Archives of Civil Engineering; 2019, 65, 2; 67-80
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Establishment of 5-Fluorouracil-resistant canine mammary tumor cell line
Autorzy:
Zhou, B.
Zhang, D.
Pei, S.M.
Zhang, K.
Du, H.C.
Jin, Y.P.
Lin, D.G.
Powiązania:
https://bibliotekanauki.pl/articles/30283.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Canine mammary tumors are the most common neoplasms in intact female dogs. The surgery cannot always solve the problem, chemotherapy are recommend to these patients. However, chemotherapy could always fail because of multidrug resistance (MDR). Through stepwise increasing 5-Fluorouracil (5-FU) concentration in the culture medium, a 5-FU-resistant canine mammary tumor cell line CMT7364/5-FU was established to disclose the molecular mechanism of the drug resistance. Cell morphology, cell sensitivity to drugs, growth curves, expression of proteins, and chemo-sensitivity in vivo were compared between the parental cell line and resistant cell line. As compared it to its parental cell line (CMT7364), CMT7364/5-FU showed different morphology, cross-resistant to other chemo-drugs and a prolonged population doubling time (PDT). The drug efflux pump proteins (ABCB1 and ABCG2) in CMT7364/5-FU were up-regulated. In vivo, the similar result revealed that CMT7364/5-FU cell line was more resistant to 5-FU. In conclusion, a 5-FU-resistant canine mammary tumor cell line (CMT7364/5-FU) was successfully established, it can serve as a good model for researching the mechanism of MDR and screening effective agents to reverse drug resistance.
Źródło:
Polish Journal of Veterinary Sciences; 2017, 20, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Preparation of Soluble Cellouronic Acid Sodium Salt by 4-Acetamide-TEMPO Mediated Oxidation of Ultrasound-Pretreated Parenchyma Cellulose from Bagasse Pith
Autorzy:
Gao, X.
Chen, K.
Zhang, H.
Peng, L.
Powiązania:
https://bibliotekanauki.pl/articles/177150.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ultrasonic pretreatment
bagasse pith
parenchyma cellulose
cellouronic acid sodium salt
4-acetamide-TEMPO
Opis:
The parenchyma cellulose isolated from bagasse pith was used as an alternative resource for preparation of water-soluble cellouronic acid sodium salt (CAS). The influence of ultrasound treatment on the cellulose was investigated for obtaining CAS by regioselective oxidization using 4-acetamide-TEMPO and NaClO with NaClO2 as a primary oxidant in an aqueous buffer at pH 6.0. The yield, carboxylate content and polymerization degree (DP) of CAS were measured as a function of ultrasonic power, agitating time and cellulose consistency by an orthogonal test. The ultrasound-treated conditions were further improved by discussion of ultrasonic power, the most important factor influencing the yield and DP. An optimized CAS yield of 72.9% with DP value (DPv) of 212 was found when the ultrasonic strength is 550 W, agitating time is 3 h and cellulose consistency is 2.0%. The oxidation reactivity of cellulose was improved by ultrasonic irradiation, whereas no significant changes in crystallinity of cellulose were measured after ultrasonic treatment. Moreover, the ultrasound treatment has a greater effect on yielding CAS from parenchyma cellulose than from bagasse fibrous’ one. The CAS was further characterized by Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM).
Źródło:
Archives of Acoustics; 2014, 39, 2; 267-275
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and test of a new high-current electronic current transformer with a Rogowski coil
Autorzy:
Zhang, M.
Li, K.
He, S.
Wang, J.
Powiązania:
https://bibliotekanauki.pl/articles/221051.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Rogowski coil
high-current
electronic current transformers
electrical measurements
Opis:
This paper describes the design and test of a new high-current electronic current transformer based on a Rogowski coil. For better performances, electronic current transformers are used to replace conventional electro-magnetic inductive current transformers based on ferromagnetic cores and windings to measure high-current on the high voltage distribution grids. The design of a new high-current electronic current transformer is described in this paper. The principal schemes of the prototype and partial evaluation results are presented. Through relative tests it is known that the prototype has a wide dynamic range and frequency band, and it can allow high accuracy measurements.
Źródło:
Metrology and Measurement Systems; 2014, 21, 1; 121-132
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple Frequency Ultrasounds Assisted Oil Sands Separation Technology
Autorzy:
Liao, K.
Ge, J.
Zhang, G.
Fu, L.
Powiązania:
https://bibliotekanauki.pl/articles/177718.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
multiple frequency ultrasounds
cavitation effect
oil sands separation
synergistic effect
Opis:
Ultrasound has a wide range of applications in oil sands separation industry due to its green and nopolluting characteristics. The combined ultrasounds technology has been widely used in many industries by virtue of the synergistic effect of cavitation effect; meanwhile, dual-frequency ultrasounds have been reported being used in lotion oil sands technology. Based on this idea, this study focuses on the application of multiple frequency ultrasounds in oil sands separation, and a comparative study has been conducted between the combined ultrasounds systems with the difference in the number of the ultrasound. The results show that the oil production rate of the samples treated by the lotion of sodium dodecyl benzene sulfonate (SDBS) and assisted by multiple frequency ultrasounds (96%) is significantly higher than that of the single frequency ultrasound (76%); the bigger the number of the ultrasound participating in the combination is, the higher the oil production rate of the oil sands is; the lower the frequency of the ultrasounds employed in the combined system is, the higher the oil production rate is. The optimum treating conditions for tri-frequency ultrasounds assisted technology are as follow: the treating time is 10-15 min, the treating temperature is 20-30°C, the concentration of surfactant in the lotion is 1.5 g/l, and the mass ratio of the lotion to oil sands is 1.8. In short, the use of multiple frequency ultrasounds can improve the oil production rate of oil sands, reduce the energy consumption during the separation process, and reduce the environmental contamination; therefore, multiple frequency ultrasounds assisted oil sands separation technology is a promising technology for oil sands resources exploitation with high efficiency.
Źródło:
Archives of Acoustics; 2017, 42, 4; 767-773
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An on-site calibration system for electronic instrument transformers based on LabVIEW
Autorzy:
Zhang, M.
Li, K.
Wang, J.
He, S.
Powiązania:
https://bibliotekanauki.pl/articles/221656.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
calibration system
electronic instrument transformers
data acquisition
data synchronization
LabVIEW
Opis:
Electronic voltage transformers (EVT) and electronic current transformers (ECT) are important instruments in a digital substation. For simple, rapid and convenient development, the paper proposed an on-site calibration system for electronic instrument transformers based on LabVIEW. In the system, analog signal sampling precision and dynamic range are guaranteed by the Agilent 3458A digital multimeter, and data synchronization is also achieved based on a self-developed PCI synchronization card. To improve the measurement accuracy, an error correction algorithm based on the Hanning window interpolation FFT has good suppression of frequency fluctuation and inter-harmonics interference. The human-computer interface and analysis algorithm are designed based on LabVIEW, and the adaptive communication technology is designed based on IEC61850 9-1/2. The calibration system can take into account pairs of digital output and analog output of the electronic voltage/current transformer calibration. The results of system tests show that the calibration system can meet the requirements of 0.2 class calibration accuracy, and the actual type test and on-site calibration also show that the system is easy to operate with convenience and satisfactory stability.
Źródło:
Metrology and Measurement Systems; 2014, 21, 2; 257-270
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of Twinned Dendrites of Al-Zn Alloy with High Zn Content
Autorzy:
Gao, K.
Song, W.
Fan, L.
Ding, Y.
Guo, X.
Zhang, R.
Powiązania:
https://bibliotekanauki.pl/articles/351396.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
directional solidification
twinned dendrite
microstructure
growth orientation
deviation angle
Opis:
Twinned dendrites in Al-Zn alloy with high Zn content (40% wt.%) were successfully prepared by directional solidification. At different directional solidification rates (1000 and 1500 μm/s), microstructures and growth orientation variations of Al twinned dendrite and non-twinned dendrite were characterized. By using the inverted trapezoidal graphite sleeve at 1000 μm/s, Al twinned dendrite were formed to developed feather crystal structures in longitudinal section. Its primary and secondary twinned dendrite were grew along [110] direction. Moreover the deviation angle between [110] direction of Al twinned dendrite and the heat flow direction was about 27.15°. While not using the inverted trapezoidal graphite sleeve at 1000 and 1500 μm/s, Al dendrite was the non-twinned dendrite and the twinned dendrite was not appeared. The experimental results showed that the higher temperature gradient, a certain pulling rate and convection environment were the formation conditions of twinned dendrites.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 4; 1657-1662
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of genistein on the gene expressions of androgen generating key enzymes StAR, P450scc and CYP19 in rat ovary
Autorzy:
Chi, X.X.
Chu, X.L.
Zhang, T.
Cao, L.K.
Powiązania:
https://bibliotekanauki.pl/articles/2087521.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
genistein
steroidogenic acute regulatory protein
side-chain cleavage enzymes
cytochrome P450 aromatase
rat ovary
Źródło:
Polish Journal of Veterinary Sciences; 2019, 2; 279-286
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modulation of virulence genes by the two-component system PhoP - PhoQ in avian pathogenic Escherichia coli
Autorzy:
Tu, J.
Huang, B.
Zhang, Y.
Xue, T.
Li, S.
Qi, K.
Powiązania:
https://bibliotekanauki.pl/articles/30418.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Avian pathogenic Escherichia coli (APEC) infections are a very important problem in the poultry industry. PhoP-PhoQ is a two-component system that regulates virulence genes in APEC. In this study, we constructed strains that lacked the PhoP or PhoQ genes to assess regulation of APEC pathogenicity by the PhoP-PhoQ two-component system. The PhoP mutant strain AE18, PhoQ mutant strain AE19, and PhoP/PhoQ mutant strain AE20 were constructed by the Red homologous recombination method. Swim plates were used to evaluate the motility of the APEC strains, viable bacteria counting was used to assess adhesion and invasion of chick embryo fibroblasts, and Real-Time PCR was used to measure mRNA expression of virulence genes. We first confirmed that AE18, AE19, and AE20 were successfully constructed from the wild-type AE17 strain. AE18, AE19, and AE20 showed significant decreases in motility of 70.97%, 83.87%, and 37.1%, respectively, in comparison with AE17. Moreover, in comparison with AE17, AE18, AE19, and AE20 showed significant decreases of 63.11%, 65.42%, and 30.26%, respectively, in CEF cell adhesion, and significant decreases of 59.83%, 57.82%, and 37.90%, respectively, in CEF cell invasion. In comparison with AE17, transcript levels of sodA, polA, and iss were significantly decreased in AE18, while transcript levels of fimC and iss were significantly decreased in AE19. Our results demonstrate that deletion of PhoP or PhoQ inhibits invasion and adhesion of APEC to CEF cells and significantly reduces APEC virulence by regulating transcription of virulence genes.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Biological characteristics of a new antibacterial peptide and its antibacterial mechanisms against Gram-negative bacteria
Autorzy:
Pei, Z.
Ying, X.
Tang, Y.
Liu, L.
Zhang, H.
Liu, S.
Zhang, D.
Wang, K.
Kong, L.
Gao, Y.
Ma, H.
Powiązania:
https://bibliotekanauki.pl/articles/2087656.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
antimicrobial peptide
biological characteristics
antibacterial mechanism
Gram-negative bacteria
Źródło:
Polish Journal of Veterinary Sciences; 2018, 21, 3; 533-542
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Y Addition Effects on Hot Deformation Behavior of Cu-Zr Alloys with High Zr Content
Autorzy:
Tian, K.
Tian, B.
Volinsky, A. A.
Zhang, Y.
Liu, Y.
Du, Y.
Powiązania:
https://bibliotekanauki.pl/articles/350979.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Cu-1%Zr alloy
high Zr content
yttrium
hot deformation activation energy
dynamic recrystallization
Opis:
Isothermal hot compression experiments were carried out using the Gleeble-1500D thermal mechanical simulator. The flow stress of the Cu-1%Zr and Cu-1%Zr-0.15%Y alloys was studied at hot deformation temperature of 550°C, 650°C, 750°C, 850°C, 900°C and the strain rate of 0.001 s-1, 0.01 s-1, 0.1 s-1, 1 s-1, 10 s-1. Hot deformation activation energy and constitutive equations for two kinds of alloys with and without yttrium addition were obtained by correlating the flow stress, strain rate and deformation temperature. The reasons for the change of hot deformation activation energy of the two alloys were analyzed. Dynamic recrystallization microstructure evolution for the two kinds of alloys during hot compression deformation was analyzed by optical and transmission electron microscopy. Cu-1%Zr and Cu-1%Zr-0.15%Y alloys exhibit similar behavior of hot compression deformation. Typical dynamic recovery occurs during the 550-750°C deformation temperature, while dynamic recrystallization (DRX) occurs during the 850-900°C deformation temperature. High Zr content and the addition of Y significantly improved Cu-1%Zr alloy hot deformation activation energy. Compared with hot deformation activation energy of pure copper, hot deformation activation energy of the Cu-1%Zr and Cu-1%Zr-0.15%Y alloys is increased by 54% and 81%, respectively. Compared with hot deformation activation energy of the Cu-1%Zr alloy, it increased by 18% with the addition of Y. The addition of yttrium refines grain, advances the dynamic recrystallization critical strain point and improves dynamic recrystallization.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 2; 875-882
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement of the Indentation Modulus and the Local Internal Friction in Amorphous SiO2 Using Atomic Force Acoustic Microscopy
Autorzy:
Zhang, B.
Wagner, H.
Büchsenschütz-Göbeler, M.
Luo, Y.
Küchemann, S.
Arnold, W.
Samwer, K.
Powiązania:
https://bibliotekanauki.pl/articles/352901.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
amorphous materials
potential energy landscape
internal friction
atomic force acoustic microscopy
Opis:
For the past two decades, atomic force acoustic microscopy (AFAM), an advanced scanning probe microscopy technique, has played a promising role in materials characterization with a good lateral resolution at micro/nano dimensions. AFAM is based on inducing out-of-plane vibrations in the specimen, which are generated by an ultrasonic transducer. The vibrations are sensed by the AFM cantilever when its tip is in contact with the material under test. From the cantilver’s contactresonance spectra, one determines the real and the imaginary part of the contact stiffness k*, and then from these two quantities the local indentation modulus M' and the local damping factor Qloc-1 can be obtained with a spatial resolution of less than 10 nm. Here, we present measured data of M' and of Qloc-1 for the insulating amorphous material, a-SiO2. The amorphous SiO2 layer was prepared on a crystalline Si wafer by means of thermal oxidation. There is a spatial distribution of the indentation modulus M' and of the internal friction Qloc-1. This is a consequence of the potential energy landscape for amorphous materials.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 9-12
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
SYBR Green-based real-time polymerase chain reaction assay for detection of porcine parvovirus 6 in pigs
Autorzy:
Sun, P.
Bai, C.X.
Zhang, D.
Wang, J.
Yang, K.K.
Cheng, B.Z.
Li, Y.D.
Wang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/2087328.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
porcine parvovirus 6
real-time polymerase chain reaction
SYBR Green
Źródło:
Polish Journal of Veterinary Sciences; 2020, 23, 2; 197-202
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Teaching Machines on Snoring : A Benchmark on Computer Audition for Snore Sound Excitation Localisation
Autorzy:
Qian, K.
Janott, C.
Zhang, Z.
Deng, J.
Baird, A.
Heiser, C.
Hohenhorst, W.
Herzog, M.
Hemmert, W.
Schuller, B.
Powiązania:
https://bibliotekanauki.pl/articles/177964.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
snore sound
obstructive sleep apnea
acoustic features
machine learning
Opis:
This paper proposes a comprehensive study on machine listening for localisation of snore sound excitation. Here we investigate the effects of varied frame sizes, and overlap of the analysed audio chunk for extracting low-level descriptors. In addition, we explore the performance of each kind of feature when it is fed into varied classifier models, including support vector machines, k-nearest neighbours, linear discriminant analysis, random forests, extreme learning machines, kernel-based extreme learning machines, multilayer perceptrons, and deep neural networks. Experimental results demonstrate that, wavelet packet transform energy can outperform most other features. A deep neural network trained with subband Energy ratios reaches the highest performance achieving an unweighted average recall of 72.8% from four types for snoring.
Źródło:
Archives of Acoustics; 2018, 43, 3; 465-475
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-15 z 15

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