oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 11 )

2018 ( 100 )

2017 ( 105 )

2016 ( 112 )

Custom range...

Search Results: 1 - 10 of 7374 matches for " Lijun Mao "
All listed articles are free for downloading (OA Articles)
Page 1 /7374
Display every page Item
Research on the Geological Sourcing of Raohe Honey by Inductively Coupled Plasma Mass Spectrometry with Primary Composite Analysis and Forecasting Models  [PDF]
Lijun Mao
American Journal of Analytical Chemistry (AJAC) , 2015, DOI: 10.4236/ajac.2015.65046
Abstract: Raohe honey (Honey in Raohe) is the only product which has obtained China’s national geographical mark for honey; however, it is always counterfeited by some producers due to its excellent quality. In this research, Raohe honey was identified by geographical sourcing, where the detection on 166 Raohe honey samples and 31 non-Raohe honey samples was conducted with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Additionally, the method of Primary Composite Analysis accomplished dimensionality reduction by transforming the abundance ratios variables of 13 isotopes to 4 primary composites, and could explain 91.17% of the total variables. There were five models: Decision Tree, Naive Bayes, Neural Network, Partial Least Square Discriminate and Support Vector Machine, built on the four new variables of primary composites with the Agilent MPP Software. The validation of the models was performed with 11 Raohe honey samples and 5 non-Raohe honey samples randomly selected. The accuracies of the Decision Tree and Support Vector Machine models were both 93.97%, and those of the Naive Bayes and Neural Network models were both 87.5%, while the contribution rate of the Partial Least Square Discriminate model was only 75%. It was concluded that the Decision Tree and Support Vector Machine models could be used for indentifying Raohe honey, and the Naive Bayes and Neural Network models could work as references, while the Partial Least Square Discriminate model was not suitable for identifying Raohe honey.
Application of Portable Near-Infrared Spectrometer for Analysis of Organic Carbon in Marine Sediments  [PDF]
Jing Yu, Jiangmei Mao, Tao Pan, Pimao Chen, Lijun Yao
Journal of Geoscience and Environment Protection (GEP) , 2017, DOI: 10.4236/gep.2017.55008
Abstract: The performance of a portable near-infrared (NIR) spectrometer to determine organic carbon (OC) in marine sediments was evaluated. The NIR reflection spectra of 180 samples in the range 950 - 1650 nm were acquired using an ultra-compact spectrometer. NIR spectroscopy combined with the partial least squares (PLS) regression and Savitzky-Golay (SG) smoothing was successfully applied to rapid and reagent-free determination of OC. Using the PLS-SG model with 1nd order derivative, 2th polynomial and eleven smoothing points, the root-mean-square errors (RMSEPM) and correlation coefficients (RP,M) of prediction for modeling were 0.073% and 0.894, respectively, the root-mean-square errors (RMSEPV) and correlation coefficients (RP,V) of prediction for validation were 0.075% and 0.883, respectively. Results showed that the small portable NIR instrument achieved well prediction effect for the analysis of OC in marine sediments, which had advantages of rapid, easy to carry and operate suitable for large-scale applications to analyze marine sediments.
Central cholinergic signal-mediated neuroendocrine regulation of vasopressin and oxytocin in ovine fetuses
Lijun Shi, Caiping Mao, Fanxing Zeng, Yuying Zhang, Zhice Xu
BMC Developmental Biology , 2008, DOI: 10.1186/1471-213x-8-95
Abstract: Chronically prepared near-term ovine fetuses (0.9 gestation) received an i.c.v. carbachol (3 μg/kg). Fetal blood samples were collected for AVP and OT assay, and brains were used for c-fos mapping studies. I.c.v. carbachol significantly increased fetal plasma AVP and OT concentrations. Intense FOS immunoreactivity (FOS-ir) was observed in the fetal supraoptic nuclei (SON) and paraventricular nuclei (PVN) in the hypothalamus. Double labeling demonstrated that a number of AVP- and OT-containing neurons in the fetal SON and PVN were expressing c-fos in response to central carbachol.The results indicate that the central cholinergic mechanism is established and functional in the regulation of the hypothalamic neuropeptides during the final trimester of pregnancy. This provides evidence for a functional link between the development of central cholinergic mechanisms and hypothalamic neuropeptide systems in the fetus.The central nervous system (CNS) contains extensive cholinergic components [1], and central cholinergic pathways play an important role in the control of cardiovascular and body fluid homeostasis [2-6]. Carbachol, as a cholinergic agonist elicits a variety of neurobiological and physiological responses, including pressor responses, thirst, natriuresis as well as secretion and release of arginine vasopressin (AVP) in adult models [1,7-11].AVP and oxytocin (OT) are two major neuropeptides synthesized and released by magnocellular neurosecretory neurons in the hypothalamus. Both of them are involved in vascular functions and hydromineral homeostasis [12]. A variety of signals, including the central cholinergic stimulation, can cause release of AVP and OT in adults [13,14]. It is unknown however whether central cholinergic mechanisms have been developed in utero in the control of AVP and OT systems in the fetal hypothalamus. Addressing this question is important to both prenatal and postnatal health problems. Despite this, our recent study has shown that intracereb
Density Functional Study of Excess Fe in Fe$_{1+x}$Te: Magnetism and Doping
Lijun Zhang,D. J. Singh,Mao-Hua Du
Physics , 2008, DOI: 10.1103/PhysRevB.79.012506
Abstract: The electronic and magnetic properties of the excess Fe in iron telluride Fe$_{(1+x)}$Te are investigated by density functional calculations. We find that the excess Fe occurs with valence near Fe$^{+}$, and therefore provides electron doping with approximately one carrier per Fe, and furthermore that the excess Fe is strongly magnetic. Thus it will provide local moments that interact with the plane Fe magnetism, and these are expected to persist in phases where the magnetism of the planes is destroyed for example by pressure or doping. These results are discussed in the context of superconductivity.
Fe K lines in the nuclear region of M82
Jiren Liu,Lijun Gou,Weimin Yuan,Shude Mao
Physics , 2013, DOI: 10.1093/mnrasl/slt145
Abstract: We study the spatial distribution of the Fe 6.4 and 6.7 keV lines in the nuclear region of M82 using the Chandra archival data with a total exposure time of 500 ks. The deep exposure provides a significant detection of the Fe 6.4 keV line. Both the Fe 6.4 and 6.7 keV lines are diffuse emissions with similar spatial extent, but their morphology do not exactly follow each other. Assuming a thermal collisional-ionization-equilibrium model, the fitted temperatures are around 5-6 keV and the Fe abundances are about 0.4-0.6 solar value. We also report the spectrum of a point source, which shows a strong Fe 6.7 keV line and is likely a supernova remnant or a superbubble. The fitted Fe abundance of the point source is 1.7 solar value. It implies that part of the iron may be depleted from the X-ray emitting gases as the predicted abundance is about 5 solar value assuming complete mixing. If this is a representative case of the Fe enrichment, a mild mass-loading of a factor of 3 will make the Fe abundance of the point source in agreement with that of the hot gas, which then implies that most of the hard X-ray continuum (2-8 keV) of M82 has a thermal origin. In addition, the Fe 6.4 keV line is consistent with the fluorescence emission irradiated by the hard photons from nuclear point sources.
Study on the Seismogenic Mechanism of the Earthquake Mw6.9 in 2014 in the Aegean Sea Seismic Cone  [PDF]
Lijun Chen
International Journal of Geosciences (IJG) , 2016, DOI: 10.4236/ijg.2016.75052
Abstract: In accordance with the Seismo-Geothermics theory about methods of intracrustal strong earthquake and volcano prediction, we use the ANSS earthquake catalogue from the Northern California earthquake data center and the EMSC earthquake catalogue from the European-Mediterranean Seismological Centre to study the seismic activities of the Turkish Branch Seismic Cone in the Mediterranean Seismic Cone and the following Aegean Sea Seismic Cone, and show reproduction through graphics and animation, the seismogenic process and seismogenic mechanism of the earthquake Mw6.9 on May 24,2014 innorthern Aegean Sea. It was concluded that the energy of strong earthquake of magnitude around7 inAegean Seawas probably from energy transfer and accumulation in deep mantle and incentive lithosphere in the way of wave pattern, and then the strong earthquake occurs suddenly in search of the weak parts of the surface structure. The purpose of this paper is to open a hole in the traditional seismic genesis, and it is beneficial to the further research on the theory and method of earthquake prediction. It is our first attempt to study this case and it needs further examination. In this paper, we divide the Turkish Branch Seismic Cone of the Mediterranean Seismic Cone into 4 tertiary seismic cones, and we show a preliminary seismo-tectonic model of Aegean region. It will be conducive to seismic monitoring and earthquake prediction research inGreece,Turkey,RomaniaandPolandregions. At present, the world’s earthquake prediction has little effect, and it even tends to be not cognitive. Innovative thinking is the only way out.
Introducing antisense waxy gene into rice seeds reduces grain amylose contents using a safe transgenic technique
Jianyue Li,Wanxia Mao,Lijun Yang,Genyu Zhou,Jia Liu,Qitao Yan,Dong Mi
Chinese Science Bulletin , 2005, DOI: 10.1360/982004-378
Abstract: An agrobacterium tumefaciensmediated co-transformation method was established and successfully used to transfer an antisense waxy gene into rice. The binary vector pl3W4 contains an antisense waxy gene, a hygromycin resistance gene (hpt) and a report gene (gus). The other binary vector pl3W8 contains only an antisense waxy gene in the T-DNA region. Two separate strains of A. tumefaciens, containing pl3W4 and pl3W8 mixed at a ratio of 1: 9, were used to transform a high-yield rice strain Chao 2–10. A total of 34 transgenic plants were obtained. PCR analysis showed that 15 of them were co-transformed. After GUS staining, the T1 seeds with GUS positive were eliminated. The GUS negative T1 seeds were germinated, and the seedlings were analyzed for the existence of antisense waxy gene. The transgenic T1 plants with only antisense waxy gene further were confirmed through Southern blot analysis. The T2 seeds collected from marker-free T1 plants were used for amylose content analysis. The results showed that the amylose content in marker-free transgenic seeds reduced by up to 28.61% over the wild type rice. This marker-free transgenic rice with low amylose contents obtained in this project could be used to screen soft grain, and could also be used as a new rice resource for eating quality improvement.
How Well Can Centenarians Hear?
Zhongping Mao, Lijun Zhao, Lichun Pu, Mingxiao Wang, Qian Zhang, David Z. Z. He
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0065565
Abstract: With advancements in modern medicine and significant improvements in life conditions in the past four decades, the elderly population is rapidly expanding. There is a growing number of those aged 100 years and older. While many changes in the human body occur with physiological aging, as many as 35% to 50% of the population aged 65 to 75 years have presbycusis. Presbycusis is a progressive sensorineural hearing loss that occurs as people get older. There are many studies of the prevalence of age-related hearing loss in the United States, Europe, and Asia. However, no audiological assessment of the population aged 100 years and older has been done. Therefore, it is not clear how well centenarians can hear. We measured middle ear impedance, pure-tone behavioral thresholds, and distortion-product otoacoustic emission from 74 centenarians living in the city of Shaoxing, China, to evaluate their middle and inner ear functions. We show that most centenarian listeners had an “As” type tympanogram, suggesting reduced static compliance of the tympanic membrane. Hearing threshold tests using pure-tone audiometry show that all centenarian subjects had varying degrees of hearing loss. More than 90% suffered from moderate to severe (41 to 80 dB) hearing loss below 2,000 Hz, and profound (>81 dB) hearing loss at 4,000 and 8,000 Hz. Otoacoustic emission, which is generated by the active process of cochlear outer hair cells, was undetectable in the majority of listeners. Our study shows the extent and severity of hearing loss in the centenarian population and represents the first audiological assessment of their middle and inner ear functions.
Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
Alaska Subedi,Lijun Zhang,David J. Singh,Mao-Hua Du
Physics , 2008, DOI: 10.1103/PhysRevB.78.134514
Abstract: We report density functional calculations of the electronic structure, Fermi surface, phonon spectrum, magnetism and electron-phonon coupling for the superconducting phase FeSe, as well as the related compounds FeS and FeTe. We find that the Fermi surface structure of these compounds is very similar to that of the Fe-As based superconductors, with cylindrical electron sections at the zone corner, cylindrical hole surface sections, and depending on the compound, other small hole sections at the zone center. As in the Fe-As based materials, these surfaces are separated by a 2D nesting vector at ($\pi$,$\pi$). The density of states, nesting and Fermi surface size increase going from FeSe to FeTe. Both FeSe and FeTe show spin density wave ground states, while FeS is close to an instability. In a scenario where superconductivity is mediated by spin fluctuations at the SDW nesting vector, the strongest superconductor in this series would be doped FeTe.
Possible Superconductivity in Fe-Sb Based Materials: Density Functional Study of LiFeSb
Lijun Zhang,Alaska Subedi,D. J. Singh,Mao-Hua Du
Physics , 2008, DOI: 10.1103/PhysRevB.78.174520
Abstract: We investigate the electronic and other properties of the hypothetical compound LiFeSb in relation to superconducting LiFeAs and FeSe using density functional calculations. The results show that LiFeSb in the LiFeAs structure would be dynamically stable in the sense of having no unstable phonon modes, and would have very similar electronic and magnetic properties to the layered Fe based superconductors. Importantly, a very similar structure for the Fermi surface and a spin density wave related to but stronger than that in the corresponding As compound is found. These results are indicative of possible superconductivity analogous to the Fe-As based compounds if the spin density wave can be suppressed by doping or other means. Prospects for synthesizing this material in pure form or in solid solution with FeTe are discussed.
Page 1 /7374
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.