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Luo R.,Xiangtan Vocational and Technical College | Luo R.,Central South University | Mao D.,Central South University | Shi C.,Central South University
Petroleum Processing and Petrochemicals | Year: 2011

Tribological properties of nano-WS 2 particles in green lubricating oil, PAO-6 and rapeseed oil, were analyzed through a series of four-ball friction tests. Results show that adding nano-WS 2 particles into PAO-6 or rapeseed oil with an optimum dosage of 2% can significantly improve the extreme pressure antiwear and antifriction properties of the base oil. Furthermore, the excellent anti-wear and antifriction properties of lubricating oil having nano-WS 2 particles could be maintained in a wider range of temperature, load and speed. Source

Lu D.,Central South University | He L.,Central South University | He L.,Changde Vocational College | Xiang W.,Central South University | And 9 more authors.
Anatomical Record | Year: 2013

The CA3 area serves a key relay on the tri-synaptic loop of the hippocampal formation which supports multiple forms of mnemonic processing, especially spatial learning and memory. To date, morphometric data about human CA3 pyramidal neurons are relatively rare, with little information available for their pre- and postnatal development. Herein, we report a set of developmental trajectory data, including somal growth, dendritic elongation and branching, and spine formation, of human CA3 pyramidal neurons from midgestation stage to middle childhood. Golgi-impregnated CA3 pyramidal neurons in fetuses at 19, 20, 26, 35, and 38 weeks of gestation (GW) and a child at 8 years of age (Y) were analyzed by Neurolucida morphometry. Somal size of the impregnated CA3 cells increased age-dependently among the cases. The length of the apical and basal dendrites of these neurons increased between 26 GW to 38 GW, and appeared to remain stable afterward until 8 Y. Dendritic branching points increased from 26 GW to 38 GW, with that on the apical dendrites slightly reduced at 8 Y. Spine density on the apical and basal dendrites increased progressively from 26 GW to 8 Y. These data suggest that somal growth and dendritic arborization of human CA3 pyramidal neurons occur largely during the second to third trimester. Spine development and likely synaptogenesis on CA3 pyramidal cells progress during the third prenatal trimester and may continue throughout childhood. © 2012 Wiley Periodicals, Inc. Source

Liu C.,Central South University | Yang Y.,Central South University | Yang Y.,Xiangtan Vocational and Technical College | Hu X.,Central South University | And 5 more authors.
Frontiers in Neuroanatomy | Year: 2015

In mammalian cerebrum there exist two distinct types of interneurons expressing nitric oxide synthase (NOS). Type I neurons are large in size and exhibit heavy nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemical reaction, while type II cells are small with light NADPH-d reactivity. The time of origin of these cortical neurons relative to corticogenesis remains largely unclear among mammals. Here we explored this issue in guinea pigs using cell birth-dating and double-labeling methods. Bromodeoxyuridine (BrdU) pulse-chasing (2 doses at 50 mg/kg, 12 h apart) was given to time-pregnant mothers, followed by quantification of NADPH-d/BrdU colocalization in the parietal and temporal neocortex in offspring at postnatal day 0 (P0), P30 and P60. Type I neurons were partially colabeled with BrdU at P0, P30 and P60 following pulse-chasing at embryonic day 21 (E21), E28 and E35, varied from 2-11.3% of total population of these neurons for the three time groups. Type II neurons were partially colabeled for BrdU following pulse-chasing at E21, E28, E35 and E42 at P0 (8.6%-16.5% of total population for individual time groups). At P60, type II neurons were found to co-express BrdU (4.8-11.3% of total population for individual time groups) following pulse-chasing at E21, E28, E35, E42, E49, E56 and E60/61. These results indicate that in guinea pigs type I neurons are generated during early corticogenesis, whereas type II cells are produced over a wide prenatal time window persisting until birth. The data also suggest that type II nitrinergic neurons may undergo a period of development/differentiation, for over 1 month, before being NADPH-d reactive. © 2015 Liu, Yang, Hu, Li, Zhang, Cai, Li and Yan. Source

Yang J.,Central South University | Ren Y.,Xiangtan Vocational and Technical College | Liu M.,Central South University | Wang Q.,Central South University | Tang S.,Central South University
Journal of Central South University (Medical Sciences) | Year: 2014

Objective: To investigate the criterion-related validity of Menopause-Specific Quality of Life Questionnaire (MENQQL)-Chinese version and to evaluate the effect of menopausal symptoms on health related quality of life. Methods: This study was a cross-sectional survey. Three communities were randomly chosen in Changsha, and then 340 menopausal women aged 45-55 years were randomly chosen from the documented data of the 3 community health service centers. They were required to fill out 4 questionnaires: demographic questionnaire, MENQOL-Chinese version, Kupperman Index (KI) and World Health Organization Quality of Life (WHQOL)-BREF. Correlation analysis was used to measure the criterion-related validity. Results: MENQOL-Chinese version subscales (vasomotor, psycho-social, sexual and physical) and KI total score were positively correlated (r=0.800, 0.751, 0.607,0.906 respectively); while negatively correlated with WHOQOL-BREF total score (r =-0.694, -0.851, -0.585, -0.873 respectively); MENQOL-Chinese version subscales (vasomotor, psycho-social, sexual and physical) were significantly correlated with WHOQOL-BREF subscales (physical, psychological, social relationship, environment), and the physical domain was the highest among the correlation coefficients (r=-0.915). Conclusion: MENQOL-Chinese version shows relatively high criterion-related validity compared with KI and WHOQOL-BREF, which can be widely used to measure the quality of life of menopause women in China. Source

Chen H.-X.,Hunan University | Li F.,Hunan University | Xiao J.-N.,Hunan University | Cao Z.-Z.,Hunan University | And 3 more authors.
Guangdianzi Jiguang/Journal of Optoelectronics Laser | Year: 2011

The direct-detection optical orthogonal frequency division multiplexing (O-OFDM) system with companding transform (CT) technique is investigated by simulation and experiment to reduce the peak-to-average power ratio (PAPR) of OFDM signals and improve the sensitivity of the receiver. The simulation results show that when increasing the companding coefficient μ, the PAPR of the OFDM signal decreases and the bit error rate (BER) of the system firstly decreases and then increases. We can choose a proper μ according to the PAPR and BER of the system. The experimented results confirm that the PAPR of the OFDM signal is decreased by 3 dB, and the receiver sensitivity is improved by 2.5 dB at BER of 10-4 after transmission over a 100-km single-mode fiber when μ is 2. Source

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