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Cylindrical Invisibility Cloak with Simplified Material Parameters is Inherently Visible
Min Yan,Zhichao Ruan,Min Qiu
Physics , 2007, DOI: 10.1103/PhysRevLett.99.233901
Abstract: It was proposed that perfect invisibility cloaks can be constructed for hiding objects from electromagnetic illumination (Pendry et al., Science 312, p. 1780). The cylindrical cloaks experimentally demonstrated (Schurig et al., Science 314, p. 997) and proposed (Cai et al., Nat. Photon. 1, p. 224) have however simplified material parameters in order to facilitate easier realization as well as to avoid infinities in optical constants. Here we show that the cylindrical cloaks with simplified material parameters inherently allow the zeroth-order cylindrical wave to pass through the cloak as if the cloak is made of a homogeneous isotropic medium, and thus visible. To all high-order cylindrical waves, our numerical simulation suggests that the simplified cloak inherits some properties of the ideal cloak, but finite scatterings exist.
Coordinate transformation makes perfect invisibility cloak with arbitrary shape
Wei Yan,Min Yan,Zhichao Ruan,Min Qiu
Physics , 2007, DOI: 10.1088/1367-2630/10/4/043040
Abstract: By investigating wave properties at cloak boundaries, invisibility cloaks with arbitrary shape constructed by general coordinate transformations are confirmed to be perfectly invisible to the external incident wave. The differences between line transformed cloaks and point transformed cloaks are discussed. The fields in the cloak medium are found analytically to be related to the fields in the original space via coordinate transformation functions. At the exterior boundary of the cloak, it is shown that no reflection is excited even though the permittivity and permeability do not always have a perfect matched layer form. While at the inner boundary, no reflection is excited either, and in particular no field can penetrate into the cloaked region. However, for the inner boundary of any line transformed cloak, the permittivity and permeability in a specific tangential direction are always required to be infinitely large. Furthermore, the field discontinuity at the inner boundary always exists; the surface current is induced to make this discontinuity self-consistent. For a point transformed cloak, it does not experience such problems. The tangential fields at the inner boundary are all zero, implying no field discontinuity exists
Hepatic Myelopathy with Painful Tonic Spasm: A Case Report  [PDF]
Huanquan Liao, Zhichao Yan, Guidian Li, Hua Hong
Open Access Library Journal (OALib Journal) , 2015, DOI: 10.4236/oalib.1102078
Abstract: Hepatic myelopathy (HM) is a rare neurological complication of chronic liver disease, causing progressive spastic paraplegia or quadriplegia in the extremities with minimal sensory or sphincter impairment. In this article, the authors present one additional case with HM, with an exceptional clinical picture of painful tonic spasms within both thighs as the main complaint. A reduction in pain coinciding with a reduction in spasticity from treatments such as baclofen suggests a causal relationship between the two. We stress the importance of early recognizing this symptom before the spinal cord damage becomes irreversible.
Confirmation of Cylindrical Perfect Invisibility Cloak Using Fourier-Bessel Analysis
Zhichao Ruan,Min Yan,Curtis W. Neff,Min Qiu
Physics , 2007, DOI: 10.1103/PhysRevLett.99.113903
Abstract: A cylindrical wave expansion method is developed to obtain the scattering field for an ideal two-dimensional cylindrical invisibility cloak. A near-ideal model of the invisibility cloak is set up to solve the boundary problem at the inner boundary of the cloak shell. We confirm that a cloak with the ideal material parameters is a perfect invisibility cloak by systematically studying the change of the scattering coefficients from the near-ideal case to the ideal one. However, due to the slow convergence of the zero$^{th}$ order scattering coefficients, a tiny perturbation on the cloak would induce a noticeable field scattering and penetration.
Serum Neopterin as a Novel Marker for Carotid Artery Stenosis in Community Subjects  [PDF]
Huanquan Liao, Zhichao Yan, Hongxuan Wang, Hua Hong
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1105083
Abstract:
Background: Carotid artery stenosis (CAS) is one of the major high-risk mechanisms of stroke. Neopterin, an immune modulator secreted by macro-phages, has been reported to be elevated in patients with cerebrovascular dis-ease. However, an association between serum neopterin level and CAS has not been firmly established. Objective: To investigate the cross-sectional relation-ship between serum neopterin levels and CAS assessed by ultrasound. Meth-ods: The study participants were volunteers in a community-based cohort aim-ing to prevent stroke in Guangzhou. Bilateral carotid artery ultrasonography was performed to assess the carotid atherosclerosis. After participant criterion screening and random sampling, finally 140 subjects were studied in our pre-sent study. Enzyme-linked immunosorbent assay was performed to measured serum neopterin concentrations. Results: Neopterin level in the CAS and con-trol group was 5.4 (3.3 - 7.3) nmol/L and 4.6 (3.6 - 5.4) nmol/L respectively, with a significant difference (P < 0.05). After multivariate adjusted, neopterin levels remained an independent factor. With per 1.0 nmol/L (approximately 1 IQR) increasing, the OR value was 1.84 (95% CI: 1.25 - 2.71, P < 0.05). ROC curve of serum neopterin concentrations for the prediction of CAS revealed that the area under curve was 0.665 (P < 0.01). The cutoff value of 5.1 nmol/L had a sensitivity of 68.6% and specificity of 61.5% in detecting CAS. Conclusion: These findings demonstrate that circulating neopterin level is increased in subclinical carotid atherosclerosis population with CAS and reinforce the key roles of inflammatory response in the pathogenesis.
Performance Comparison of Three Algorithms Applied to UM2000 Signal Demodulation  [PDF]
Zhichao Qiao, Fuping Wang
Journal of Signal and Information Processing (JSIP) , 2013, DOI: 10.4236/jsip.2013.43B010
Abstract:

UM2000 signal is a type of multi-audio frequency-modulated signal which is widely used for railway blocking. Principles of three typical demodulating algorithms are presented in details in this paper. Bit error rates of the three methods at different SNRs are achieved by Monte Carlo simulation experiments. Among the three algorithms, the quadrature demodulation has the best performance at the real working environment. However, the three methods have the same problem of phase hopping when noise is too strong.

Downregulation of SPARC Expression Inhibits the Invasion of Human Trophoblast Cells In Vitro
Yahong Jiang, Yan Zhu, Yan Shi, Yaping He, Zhichao Kuang, Zhaogui Sun, Jian Wang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069079
Abstract: Successful pregnancy depends on the precise regulation of extravilloustrophoblast (EVT) invasion into the uterine decidua. SPARC (secreted protein acidic and rich in cysteine) is a matricellular glycoprotein that plays critical roles in the pathologies associated with obesity and diabetes, as well as tumorigenesis. The objective of this study was to investigate the role of SPARC in the process of trophoblast invasion which shares many similarities with tumor cell invasion. By Western blot, higher expression of SPARC was observed in mouse brain, ovary and uterus compared to other mouse tissues. Immunohistochemistry analysis revealed a spatio-temporal expression of SPARC in mouse uterus in the periimplantation period. At the implantation site of d8 pregnancy, SPARC mainly accumulated in the secondary decidua zone (SDZ), trophoblast cells and blastocyst. The expression of SPARC was also detected in human placental villi and trophoblast cell lines. In a Matrigel invasion assay, we found SPARC-specific RNA interference significantly reduced the invasion of human extravilloustrophoblast HTR8/SVneo cells. Microarray analysis revealed that SPARC depletion upregulated the expression of interleukin 11 (IL11), KISS1, insulin-like growth factor binding protein 4 (IGFBP4), collagen type I alpha 1 (COLIA1), matrix metallopeptidase 9 (MMP9), and downregulated the expression of the alpha polypeptide of chorionic gonadotropin (CGA), MMP1, gap junction protein alpha 1 (GJA1), et al. The gene array result was further validated by qRT-PCR and Western blot. The present data indicate that SPARC may play an important role in the regulation of normal placentation by promoting the invasion of trophoblast cells into the uterine decidua.
Association of MyF5, MyF6 and MyOG Gene Polymorphisms with Carcass Traits in Chinese Meat Type Quality Chicken Populations
Huadong Yin,Zhichao Zhang,Xi Lan,Xiaoling Zhao,Yan Wang,Qing Zhu
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.704.708
Abstract: The MyoD gene family has been proposed to profoundly modulate muscle development and carcass performance in farm animals. In this study, researchers examined Single Nucleotide Polymorphisms (SNPs) in the exons of the Myf5, Myf6 and MyoG genes using Polymerase Chain Reaction (PCR)-Single Strand Conformation Polymorphisms (SSCP) and DNA sequencing methods in 360 individuals from 6 commercial pure lines of Sichuan Daheng meat type quality chickens. About 2 SNPs (87T>C and 96C>T) in exon 1 of Myf5, 1 SNP (154T>C) in exon 1 of MyoG and no variation in Myf6 were detected. The 96C>T SNP in Myf5 was a rare variant and was not analyzed further. The association analysis of genotypes with carcass traits revealed that the genotypes of SNP (87T>C) in Myf5 were significantly associated with Live Weight (LW), Carcass Weight (CW), Semi-Eviscerated Weight (SEW) and Eviscerated Weight (EW) (p<0.05). The SNP genotypes (154T>C) in MyoG were significantly associated with Live Weight (LW), Carcass Weight (CW), Eviscerated Weight (EW) and Breast Muscle Weight (BMW) (p<0.05). The results suggested that Myf5 and MyoG genes are potential major genes or are in close linkage disequilibrium with the QTL affecting carcass traits in this population of chickens. The 2 SNPs may potentially have use as markers for Marker-Assisted Selection (MAS) in chicken breeding.
Effect Analysis of Heart Fatty Acid-Binding Protein Gene Assisted Selection on Intramuscular Fat Content in Chicken
Huadong Yin,Yan Wang,Xiaoling Zhao,Shiyi Chen,Zhichao Zhang,Yiping Liu,Qing Zhu
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.1595.1600
Abstract: Fatty deposition in organism is an important factor which influences meat quality. Previously, Heart Fatty Acid-Binding Protein (H-FABP) gene was studied as a candidate gene which having effect on Intramuscular Fat content (IMF). In current study, we chose four SNPs loci (g.260T>C, g.675G>A, g.783C>T and g.1198T>C) of H-FABP which have been proved to have distinct correlation with IMF as molecular markers to scan SNPs in a new breeding Chinese yellow-feather broiler population. Researchers allocated adaptive individuals into high-IMF group and low-IMF group according to the haplotypes which were constructed of genotypes at four SNP sites of each individual in F1 generation and these haplotypes had been proved to be the preponderant or recessive haplotype. The core group was chose from the F1 generation based on the traditional breeding method. And then, we detected the genotypes of the four loci by SNPs screening and analyzed the selection effect in F2 generation which were obtained from mating and crossing within each group. Results indicated that the preponderance alleles were changed at Locus 1, 3 and 4 in the three groups of F2 and there were no significant differences in IMF among the three groups (p>0.05). However, the IMF of the core group and the low fat group was higher than which of high fat group. The result of variance analysis showed that there were no significant difference in the effect of the different genotypes of the four SNPs on IMF (p>0.05). The four loci on the H-FABP gene in the research were not suitable as candidate markers to select IMF in this yellow-feather broiler strain.
Winter Hibernation and UCHL1-p34cdc2 Association in Toad Oocyte Maturation Competence
Zhichao Kuang, Yuwei Yao, Yan Shi, Zheng Gu, Zhaogui Sun, Jiake Tso
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0078785
Abstract: Currently, it is believed that toad oocyte maturation is dependent on the physiological conditions of winter hibernation. Previous antibody-blocking experiments have demonstrated that toad ubiquitin carboxyl-terminal hydrolase L1 (tUCHL1) is necessary for germinal vesicle breakdown during toad oocyte maturation. In this paper, we first supply evidence that tUCHL1 is highly evolutionarily conserved. Then, we exclude protein availability and ubiquitin carboxyl-terminal hydrolase enzyme activity as factors in the response of oocytes to winter hibernation. In the context of MPF (maturation promoting factor) controlling oocyte maturation and to further understand the role of UCHL1 in oocyte maturation, we performed adsorption and co-immunoprecipitation experiments using toad oocyte protein extracts and determined that tUCHL1 is associated with MPF in toad oocytes. Recombinant tUCHL1 absorbed p34cdc2, a component of MPF, in obviously larger quantities from mature oocytes than from immature oocytes, and p13suc1 was isolated from tUCHL1 with a dependence on the ATP regeneration system, suggesting that still other functions may be involved in their association that require phosphorylation. In oocytes from hibernation-interrupted toads, the p34cdc2 protein level was significantly lower than in oocytes from toads in artificial hibernation, providing an explanation for the different quantities isolated by recombinant tUCHL1 pull-down and, more importantly, identifying a mechanism involved in the toad oocyte’s dependence on a low environmental temperature during winter hibernation. Therefore, in toads, tUCHL1 binds p34cdc2 and plays a role in oocyte maturation. However, neither tUCHL1 nor cyclin B1 respond to low temperatures to facilitate oocyte maturation competence during winter hibernation.
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