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Search Results: 1 - 10 of 15572 matches for " Ran Hao "
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LIN Hao,ran,

动物学研究 , 2000,
Abstract: Interaction between growth and reproduction occurs in many vetebrates.The endocrine factors which regulate growth and metabolism are also affected on puberty and gonadal development.Similarly,the hormones which effect on reproduction are also influ encedongrowthandmetabolism.Recentstudiesonfish revealed the neuroendocrine interactions between the gonadotropic axis and the somatotropic axis.For example,gonadotropin releasing hormone (GnRH) and dopamine could stimulate the release of growth hormone,sex steroid could modulate growth hormone secretion;also,growth hormone could accelerate gonadal development and maturation.Some new findings from studies on fish have not yet been obtained in mammals and other vertebrates are remains to be further investigated.
Graphene Embedded Modulator with Extremely Small Footprint and High Modulation Efficiency
Ran Hao,Jia-Min Jin
Journal of Photonics , 2014, DOI: 10.1155/2014/309350
Abstract: By embedding graphene sheet in the silicon waveguide, the overall effective mode index displays unexpected symmetry and the electrorefraction effect has been significantly enhanced near the epsilon-near-zero point. An eight-layer graphene embedded Mach-Zehnder Modulator has been theoretically demonstrated with the advantage of ultracompact footprint (4 × 2?μm2), high modulation efficiency (1.316?V·μm), ultrafast modulation speed, and large extinction ratio. Our results may promote various on-chip active components, boosting the utilization of graphene in optical applications. 1. Introduction Electrooptical modulator, which transfers electronic signals into high bit-rate photonic data, is the key component in on-chip interconnection and integrated optoelectronic circuits [1]. By applying an electric field to a material, the real and imaginary part of the refractive indices can be changed. A change in the real part of the refractive index caused by the applied voltage is known as the electrorefraction (ER) effect, whereas a change in the imaginary part of the refractive index is known as the electroabsorption (EA) effect [1]. However, these two effects are too weak in pure silicon at the communication wavelengths so that it usually needs an extremely large length to reach the required modulation; for example, a 50?Gbit/s modulator has the length of 1 millimeter [2]. The large footprint of optical modulator makes it impossible to be integrated into a single chip. To fill the demands of next generation on-chip communication, minimizing the size and improving the speed of modulator become the urgent goals but remain a challenge. Recently, graphene-based modulators have attracted much attention due to their unprecedented ability to enhance the material’s EA effect; thus, they can greatly reduce the modulator length to achieve the same effect [2–5]. In [5], Lu and Zhao reported a graphene embedded modulator having a length of only 1?μm. However, limited by the inbuilt drawback from the EA modulator, the extinction ratio is low and background noise cannot be ignored. In this paper, we point out that graphene can also have significant enhancement to the ER effect of the background material. By embedding duplicated graphene layers into a silicon substrate, we demonstrated that the variation of effective mode index can be as large as 0.4057 corresponding to a Mach-Zender modulation arm length of only 1.9?μm. Note that caused by ER effect is only at the level of 10?4 for conventional semiconductor modulators [6–8]. To our knowledge, this is the largest and smallest
A 180-Day Subchronic Oral Toxicity Study of Total Flavones of E. leptorrhizum Stearn in Rats  [PDF]
Ting Liu, Lianqiang Hui, Chunyu Cao, Ran Hao, Shuangrong Gao, Rong He, Baoqiang Dai, Lifang Wang
Chinese Medicine (CM) , 2015, DOI: 10.4236/cm.2015.61005
Abstract: A subchronic oral toxicity was conducted to evaluate the safety of total flavones of E. leptorrhizum Stearn in Sprague-Dawley rats. The test article was administered once daily by gavage in male and female rats at dose levels of 24, 48, and 96 mg/kg body weight/day for 180 days. 90 and 180 days after administration, ten and tweedy animals (each half of male and female) of each group were tested. 28 days after withdrawal, five male and female rats were tested. There were no significant toxicological changes shown in daily clinical signs, body weight, food consumption, hematology parameters, blood biochemistry, organ weights and histopathological examination except leukocyte differential count. It was concluded that the no-observed-effect level (NOEL) for total flavones of E. leptorrhizum Stearn was >96 mg/kg in SD rats.
Application of Precision-Cut Rat Liver Slice to Study the Influence of Monocrotaline, Tussilago farfara Alkaloids on the Expression of Cytochrome P450 Enzymes  [PDF]
Hailin Wang, Lianqiang Hui, Chun Li, Ting Liu, Chang’an Yu, Chunyu Cao, Ran Hao, Yi Zhang
Health (Health) , 2016, DOI: 10.4236/health.2016.84039
Abstract: Precision-cut liver slice has been successfully used to study the mechanism of drug-induced hepatotoxicity, the prediction of liver toxicity, the discovery of early hepatic toxicity biomarker and the metabolism of drug in liver. We detected the expression of CYP3A4, CYP2B1 + CYP2B2 and CYP2E1 in precision-cut liver slice after co-cultured with monocrotaline or Tussilago farfara alkaloids to investigate the hepatotoxicity mechanism of those drugs. After co-culturing with monocrotaline or Tussilago farfara alkaloids for 6 hours, the expression of CYP3A4 in the microsome of precision-cut liver slices was detected by Western blot, and the expressions of CYP2B1 + CYP2B2 and CYP2E1 were detected by immunofluorescence. The results showed that monocrotaline induced the expression of CYP3A4 and CYP2B1 + CYP2B2, and Tussilago farfara alkaloids obviously up-regulated the expression of CYP2E1 and CYP3A4. Thus, we conclude that the up-regulation of CYP3A4, CYP2B1 + CYP2B2 and CYP2E1 may be one of the toxic mechanisms of liver injury of those drugs.
In Vitro Study of the Nephrotoxicity of Tripterygium Tablet Extract and Triptolide in Monolayer HK-2 Cells Cultured in a Transwell Chamber  [PDF]
Ran Hao, Lianqiang Hui, Chun Li, Chunyu Cao, Yifei Yang, Jiyuan Zhang, Ting Liu, Yi Zhang
Chinese Medicine (CM) , 2018, DOI: 10.4236/cm.2018.91003
Abstract: We established a monolayer polarized cell model using human kidney 2 (HK-2) cells cultured in a transwell chamber to examine the changes in the morphology and physiological functions of human-derived renal proximal tubular epithelial cells caused by tripterygium tablet extract (TTE) and triptolide. HK-2 cells were cultured on PCF membranes to form a complete monolayer of cells. A MTT assay was used to select 10, 40, 160, 640 μg·ml-1 TTE or 4, 16, 64, 256 ng·ml-1 triptolide to treat HK-2 monolayer cells. After 24 hours, a FITC permeability assay was performed; GGT, LDH and NAG secretion on the apical (AP) and basolateral (BL) sides of the cells by HK-2 cells were examined. The morphology and the monolayer structure of HK-2 cells was observed via optical microscope and scanning electron microscope, respectively. The effect on the cytoskeleton of HK-2 cells was observed under a fluorescence microscope. The IC50 of TTE was 277.122 μg·ml-1, and the IC50 of triptolide was 148.035 ng·ml-1. Compared with the DMSO group, the FITC leakage rate with TTE 160, 640 μg·ml-1 treated group and 4 - 256 ng·ml-1 triptolide dose group exhibited statistically significant increase. TTE significantly increased secretion of GGT and LDH at 160, 640 μg·ml-1, meanwhile, dramatically increased the AP/BL ratio of LDH at 160 μg·ml-1; triptolide significantly increased secretion and AP/BL ratio of GGT and LDH at 256 ng·ml-1. The morphological observations via optical and electron
A Study of Myocardial Ischemia Model Induced by Left Coronary Artery Ligation in Rats  [PDF]
Hailin Wang, Chunyu Cao, Lianqiang Hui, Ting Liu, Yanli Wang, Shuangrong Gao, Yi Zhang, Ran Hao, Chun Li, Chen Zang
World Journal of Cardiovascular Diseases (WJCD) , 2016, DOI: 10.4236/wjcd.2016.65014
Abstract: Objective: Coronary artery was ligated to study the characteristics of myocardial ischemia in rats. Methods: The left anterior descending artery was ligated to establish the rat model of acute myocardial ischemia. All animals were divided into normal control group, sham operation group and model group. 1, 2 and 4 weeks after modeling, ECG (II lead) was recorded, the weight of whole heart and left ventricle were recorded and organ indexes were calculated; myocardial infarct size was determined by TTC; CK, CK-MB, LDH, AST contents of serum were detected; cardiac function was determined by left ventricular intubation via carotid artery and left ventricular was taken to perform pathological observation. Results: 1 week after modeling, compared with the sham operation group, the ECG and heart function index of rats model had significant change, but the myocardial enzymes did not change significantly; 4 weeks after modeling, the ECG and cardiac function of animal models had a recovery trend, but the myocardial enzymes, including CK, CK-MB, LDH, AST, were significantly increased; 1 week after modeling, the left ventricular indexes of model rats were increased; the infarct size was about 30%, myocardial cell necrosis and granulation tissue hyperplasia could be observed in infarction area; with the modeling time extended, from 2 to 4 weeks, the left ventricular and heart indexes of model group were significantly increased; the infarct size was relatively constant, left ventricular became thickly, and fibrous or granulation tissue was significantly proliferated in infarction area under microscope. Conclusion: The indexes of myocardial ischemia induced by coronary artery ligation in rats are different at different time points. The results suggest that the time point should be selected to observe the anti-myocardial ischemia effect of the subjects from different aspects.
Testing for Heteroscedasticity in Semiparametric Random Effect Model

Zhu Zhongyi,Ran Hao,

数学物理学报(A辑) , 2006,
Abstract: It is of considerable interest in testing for heteroscedasticity in many practical studies. In this paper, the authors discuss this type of problem in framework of semiparametric mixed models. A global score test is proposed for the null hypothesis that all the variance components are zero. The test is based on the approaches of Lin (1997), the authors examine its performance in a simulation study, illustrate the test methods by using the progesterone data. The test can be easily implemented by using existing statistical softwares.
Statefinder diagnosis for the Palatini $f(R)$ gravity theories
Song Li,Hao-Ran Yu,Tong-Jie Zhang
Physics , 2010,
Abstract: The Palatini $f(R)$ gravity, is able to probably explain the late time cosmic acceleration without the need for dark energy, is studied. In this paper, we investigate a number of $f(R)$ gravity theories in Palatini formalism by means of statefinder diagnosis. We consider two types of $f(R)$ theories: (i) $f(R)=R+\alpha R^{m}-\beta R^{-n}$ and (ii) $f(R)=R+\alpha ln R+\beta$. We find that the evolutionary trajectories in the $s-r$ and $q-r$ planes for various types of the Palatini $f(R)$ theories reveal different evolutionary properties of the universe. Additionally, we use the observational $H(z)$ data to constrain models of $f(R)$ gravity.
Nonparametric reconstruction of dynamical dark energy via observational Hubble parameter data
Hao-Ran Yu,Shuo Yuan,Tong-Jie Zhang
Physics , 2013, DOI: 10.1103/PhysRevD.88.103528
Abstract: We study the power of current and future observational Hubble parameter data (OHD) on non-parametric estimations of the dark energy equation of state, $w(z)$. We propose a new method by conjunction of principal component analysis (PCA) and the criterion of goodness of fit (GoF) criterion to reconstruct $w(z)$, ensuring the sensitivity and reliability of the extraction of features in the EoS. We also give an new error model to simulate future OHD data, to forecast the power of future OHD on the EoS reconstruction. The result shows that current OHD, despite in less quantity, give not only a similar power of reconstruction of dark energy compared to the result given by type Ia supernovae, but also extend the constraint on $w(z)$ up to redshift $z\simeq2$. Additionally, a reasonable forecast of future data in more quantity and better quality greatly enhances the reconstruction of dark energy.
Influence of Fermion Velocity Renormalization on Dynamical Mass Generation in QED$_3$
Hao-Ran Chang,Jing-Rong Wang,Jing Wang
Physics , 2012, DOI: 10.1088/0256-307X/29/5/057401
Abstract: We study dynamical fermion mass generation in (2+1)-dimensional quantum electrodynamics with a gauge field coupling to massless Dirac fermions and non-relativistic scalar bosons. We calculate the fermion velocity renormalization and then examine its influence on dynamical mass generation by using the Dyson-Schwinger equation. It is found that dynamical mass generation takes place even after including the scalar bosons as long as the bosonic compressibility parameter $\xi$ is sufficiently small. In addition, the fermion velocity renormalization enhances the dynamically generated mass.
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