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276篇 您的检索式:作者名="Peng Pei"
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1De novo characterization of the root transcriptome of a traditional Chinese medicinal plant Polygonum cuspidatum显示文摘Various active components have been extracted from the root of Polygonum cuspidatum.However,the genetic basis for their activity is virtually unknown.In this study,25600002 short reads (2.3 Gb) of P.cuspidatum root transcriptome were obtained via Illumina HiSeq 2000 sequencing.A total of 86418 unigenes were assembled de novo and annotated.Twelve,18,60 and 54 unigenes were respectively mapped to the mevalonic acid (MVA),methyl-D-erythritol 4-phosphate (MEP),shikimate and resveratrol biosynthesis pathways,suggesting that they are involved in the biosynthesis of pharmaceutically important anthraquinone and resveratrol.Eighteen potential UDP-glycosyltransferase unigenes were identified as the candidates most likely to be involved in the biosynthesis of glycosides of secondary metabolites.Identification of relevant genes could be important in eventually increasing the yields of the medicinally useful constituents of the P.cuspidatum root.From the previously published transcriptome data of 19 non-model plant taxa,1127 shared orthologs were identified and characterized.This information will be very useful for future functional,phylogenetic and evolutionary studies of these plants.HAO DaCheng MA Pei MU Jun CHEN ShiLin XIAO PeiGen PENG Yong HUO Li XU LiJia SUN Chao 2012Science China(Life Sciences)2012,55,5:36
2Natural history of covert hepatic encephalopathy: An observational study of 366 cirrhotic patients显示文摘AIM To explore the natural history of covert hepatic encephalopathy(CHE) in absence of medication intervention.METHODS Consecutive outpatient cirrhotic patients in a Chinese tertiary care hospital were enrolled and evaluated for CHE diagnosis. They were followed up for a mean of 11.2 ± 1.3 mo. Time to the first cirrhosis-related complications requiring hospitalization, including overt HE(OHE), resolution of CHE and death/transplantation, were compared between CHE and no-CHE patients. Predictors for complication(s) and death/transplantation were also analyzed.RESULTS A total of 366 patients(age: 47.2 ± 8.6 years, male: 73.0%) were enrolled. CHE was identified in 131 patients(35.8%). CHE patients had higher rates of death and incidence of complications requiring hospitalization, including OHE, compared to unimpaired patients. Moreover, 17.6% of CHE patients developed OHE, 42.0% suffered persistent CHE, and 19.8% of CHE spontaneously resolved. In CHE patients, serum albumin < 30 g/L(HR = 5.22, P = 0.03) was the sole predictor for developing OHE, and blood creatinine > 133 μmol/L(HR = 4.75, P = 0.036) predicted mortality. Child-Pugh B/C(HR = 0.084, P < 0.001) and OHE history(HR = 0.15, P = 0.014) were predictors of spontaneous resolution of CHE.CONCLUSION CHE exacerbates, persists or resolves without medication intervention in clinically stable cirrhosis. Triage of patients based on these predictors will allow for more cost-effect management of CHE.An-Jiang Wang A-Ping Peng Bi-Min Li Na Gan Li Pei Xue-Lian Zheng Jun-Bo Hong Hai-Ying Xiao Jia-Wei Zhong Xuan Zhu 2017World Journal of Gastroenterology2017,23,34:22
3Bone biomaterials and interactions with stem cells显示文摘Bone biomaterials play a vital role in bone repair by providing the necessary substrate for cell adhesion,proliferation, and differentiation and by modulating cell activity and function. In past decades, extensive efforts have been devoted to developing bone biomaterials with a focus on the following issues:(1)developing ideal biomaterials with a combination of suitable biological and mechanical properties;(2)constructing a cell microenvironment with pores ranging in size from nanoscale to submicro-and microscale;and(3) inducing the oriented differentiation of stem cells for artificial-to-biological transformation. Here we present a comprehensive review of the state of the art of bone biomaterials and their interactions with stem cells. Typical bone biomaterials that have been developed, including bioactive ceramics, biodegradable polymers, and biodegradable metals, are reviewed, with an emphasis on their characteristics and applications. The necessary porous structure of bone biomaterials for the cell microenvironment is discussed,along with the corresponding fabrication methods. Additionally, the promising seed stem cells for bone repair are summarized, and their interaction mechanisms with bone biomaterials are discussed in detail.Special attention has been paid to the signaling pathways involved in the focal adhesion and osteogenic differentiation of stem cells on bone biomaterials. Finally, achievements regarding bone biomaterials are summarized, and future research directions are proposed.Chengde Gao Shuping Peng Pei Feng Cijun Shuai 2017Bone Research2017,5,4:17
4Oral berberine improves brain dopa/dopamine levels to ameliorate Parkinson’s disease by regulating gut microbiota显示文摘The phenylalanine-tyrosine-dopa-dopamine pathway provides dopamine to the brain.Iin this process,tyrosine hydroxylase(TH)isthe rate-limiting enzyme that hydroxylates tyrosine and generates levodopa(L-dopa)with tetranydrobiopterin(BH_(4))as a coenzyme.Here,we show that oral berberine(BBR)might supply H^(·) through dihydroberberine(reduced BBR produced by bacterial nitroreductase)and promote the production of BHl from dihydrobiopterin;the increased BH,enhances TH activity,which accelerates the production of L-dopa by the gut bacteria.Oral BBR acts in a way similar to vitamins.The L-dopa produced by theintestinal bacteria enters the brain through the circulation and is transformed to dopamine.To verify the gut-brain dialog activatedby BBR's effect,Enterococcus foecalis or Enterococcus faecium was transplanted into Parkinson's disease(PD)mice.The bacteriasignificantly increased brain dopamine and ameliorated PD manifestation in mice;additionally,combination of BBR with bacteriashowed better therapeutic effect than that with bacteria alone.Moreover,2,4,6-trimethy-pyranylium tetrafluoroborate(TMP-TFB)-derivatized matrix-assisted laser desorption mass spectrometry(MALDI-MS)imaging of dopamine identihed elevated striataldopamine levels in mouse brains with oral Enterococcus,and BBR strengthened the imaging intensity of brain dopamine.Theseresults demonstrated that BBR was an agonist of TH in Enterococcus and could lead to the production of L-dopa in the gut.Furthermore,a study of 28 patients with hyperlipidemia conhrmed that oral BBR increased bloodfecal L-dopa by the intestinalbacteria.Hence,BBR might improve the brain function by upregulating the biosynthesis of-dopa in the gut microbiota through avitamin-like effect.Yan Wang Qian Tong Shu-Rong Ma Zhen-Xiong Zhao Li-Bin Pan Lin Cong Pei Han Ran Peng Hang Yu Yuan Lin Tian-Le Gao Jia-Wen Shou Xiao-Yang Li Xian-Feng Zhang Zheng-Wei Zhang Jie Fu Bao-Ying Wen Jin-Bo Yu Xuetao Cao Jian-Dong Jiang 2021Signal Transduction and Targeted Therapy2021,6,3:16
5Generation of RAG 1- and 2-deficient rabbits by embryo microinjection of TALENs显示文摘Jun Song Juan Zhong Xiaogang Guo Yongqiang Chen Qingjian zou Jiao Huang Xiaoping Li Quanjun Zhang Zhiwu Jiang Chengcheng Tang Huaqiang Yang Tao Liu Peng Li Duanqing Pei Liangxue Lai 2013Cell Research2013,23,8:15
6Monitoring and Warning of Landslides and Debris Flows Using an Optical Fiber Sensor Technology显示文摘Landslides and debris flows are typical geo-hazards which occur in hilly or mountainous regions. Debris flows may result from landslides. Geotechnical instrumentation plays an important role in monitoring and warning of landslides and resulted debris flows. Traditional technologies for monitoring landslides and debris flows have certain limitations. The new optical fiber sensors presented in this paper can overcome those limitations. This paper presents two new optical fiber sensor systems: one is the Fiber Bragg Grating (FBG)-based in-place inclinometer for monitoring landslides and the other is the FBG-based column-net system for monitoring debris flows. This paper presents the calibration results of FBG-based in-place inclinometers in laboratory. It is found that the calibration results are in good agreement with theoretical results. Both the FBG-based in-place inclinometers and the FBG-based column-net system have been installed at a site in Weijiagou valley, Beichuan County, Sichuan Province of China. Some preliminary results have been obtained and reported in the paper. The advantages of the FBG monitoring systems and their potential applications are also presented.PEI Huafu CUI Peng YIN Jianhua ZHU Honghu CHEN Xiaoqing PEI Laizheng 2011Journal of Mountain Science2011,8,5:12
7Study on the physiological indices of Pinus sibirica and Pinus koraiensis seedlings under cold stress显示文摘Although Pinus sibirica and Pinus koraiensis are resistant to cold or low temperatures in the cold temperate regions of the northern hemisphere,the former has a stronger cold resistance.Research has been limited to the comparison of physiological responses of the two species to cold stress.In this study,5-year-old seedlings of P.sibirica and P.koraiensis were subjected to six temperature treatments,[20℃(control),0℃,-20℃,-40℃,-60℃,and-80℃],under different stress periods(6,12,24,and 48 h).The results showed that differences in each physiological index were significant between P.sibirica and P.koraiensis,except for the permeability of cell membranes,reactive oxygen species,proline and soluble proteins.An ANOVA test indicated that there were extreme differences among the temperatures for each index,stress time and temperature 9 time for most indices.All indices showed a similar trend for P.sibirica and P.koraiensis with decreasing temperature or the extension of stress time.Soluble sugars and proline increased at 0 to-20℃and then remained unchanged with temperature decline.Other indices showed an increase from 20 to-20℃,stable from-20 to-40℃and a decrease from-40 to-80℃.All the indices increased and then declined along with the prolonged cold stress time,except for the control.From 0 to-40℃,the permeability of cell membranes,relative conductivity,reactive oxygen species and malonaldehyde of P.koraiensis seedlings were higher than in P.sibirica,but superoxide dismutase,peroxidase,catalase activity and soluble sugars,proline,and soluble proteins content emerged as opposite.This study compared the physiological mechanism responses to cold stress between P.sibirica and P.koraiensis to provide the basis for the introduction,distribution,and genetic improvement of these coniferous species.Fang Wang Deyang Liang Xiaona Pei Qinhui Zhang Peng Zhang Jianqiu Zhang Zhimin Lu Yuchun Yang Guifeng Liu Xiyang Zhao 2019Journal of Forestry Research2019,30,4:12
8Association of CYP3A polymorphisms with the pharmacokinetics of cyclosporine A in early post- renal transplant recipients in China显示文摘目的: 回顾地评估细胞色素 P450 3A (CYP3A ) 和 ATP 有约束力的盒子亚科 B 的协会成员 1 (ABCB1 ) 有用汉语的 cyclosporine A (CsA ) 的 pharmacokinetics 的基因多型性肾移植病人。Xiang-guang MENG Cheng-xian GUO Guo-qing FENG Ying-chun ZHAO Bo-ting ZHOU Jian-le HAN Xin CHEN Yong SHI Hong-yao SHI Ji-ye YIN Xiang-dong PENG Qi PEI Wei ZHANG Guo WANG Meng HE Min LIU Jing-ke YANG Hong-hao ZHOU 2012Acta Pharmacologica Sinica2012,33,12:11
9Synthesis of a benzoxazine monomer containing maleimide and allyloxy groups显示文摘新奇 benzoxazine 单体 3-(4-allyloxy )phenyl-3,4-dihydro-2H-6-(N-maleimido )-1,3-benzoxazine (AMB ) 被综合,结构被英尺红外证实,(1 ) H NMR。AMB 的热分析(DSC ) 证明烯丙氧基组的介绍减少了熔点并且展出了一扇狭窄、对称的治好的发热的窗户。Yan Tang Qing Lai Zhao Ke Zeng Pei Kai Miao Ke Zhou Wen Rui Tang Hong Fei Zhou Tao Liu Yi Peng Wang Gang Yang 2007Chinese Chemical Letters2007,18,8:10
10Experimental study on operative methods of pancreaticojejunostomy with reference to anastomotic patency and postoperative pancreatic exocrine function显示文摘AIM:To assess the patency of pancreaticoenterostomy and pancreatic exocrine function after three surgical methods. METHODS: A pig model of pancreatic ductal dilation was made by ligating the main pancreatic duct. After 4 wk ligation, a total of 36 piglets were divided randomly into four groups. The piglets in the control group underwent laparotomy only; the others were treated by three anastomoses: (1) end-to-end pancreaticojejunostomy invagination (EEPJ); (2) end-to-side duct-to- mucosa sutured anastomosis (ESPJ); or (3) binding pancreaticojejunostomy (BPJ). Anastomotic patency was assessed after 8 wk by body weight gain, intrapancreatic ductal pressure, pancreatic exocrine function secretin test, pancreatography, and macroscopic and histologic features of the anastomotic site. RESULTS: The EEPJ group had significantly slower weight gain than the ESPJ and BPJ groups on postoperative weeks 6 and 8 (P < 0.05). The animals in both the ESPJ and BPJ groups had a similar body weight gain.Intrapancreatic ductal pressure was similar in ESPJ and BPJ. However, pressure in EEPJ was significantly higher than that in ESPJ and BPJ (P < 0.05). All three functional parameters, the secretory volume, the flow rate of pancreatic juice, and bicarbonate concentration, were significantly higher in ESPJ and BPJ as compared to EEPJ (P < 0.05). However, the three parameters were similar in ESPJ and BPJ. Pancreatography performed after EEPJ revealed dilation and meandering of the main pancreatic duct, and the anastomotic site exhibited a variable degree of occlusion, and even blockage. Pancreatography of ESPJ and BPJ, however, showed normal ductal patency. Histopathology showed that the intestinal mucosa had fused with that of the pancreatic duct, with a gradual and continuous change from one to the other. For EEPJ, the portion of the pancreatic stump protruding into the jejunal lumen was largely replaced by cicatricial fibrous tissue. CONCLUSION: A mucosa-to-mucosa pancreatico- jejunostomy is the best choice for anastomotic patency when compared with EEPJ. BPJ can effectively maintain anastomotic patency and preserve pancreatic exocrine function as well as ESPJ.Ming-Dong Bai Liang-Qun Rong Lian-Chen Wang Hai Xu Rui-Fang Fan Pei Wang Xiao-Peng Chen Liu-Bin Shi Shu-You Peng 2008World Journal of Gastroenterology2008,14,3:9
11Combination of mild therapeutic hypothermia and adipose-derived stem cells for ischemic brain injury显示文摘Mild therapeutic hypothermia has been shown to mitigate cerebral ischemia, reduce cerebral edema, and improve the prognosis of patients with cerebral ischemia. Adipose-derived stem cell-based therapy can decrease neuronal death and infiltration of inflammatory cells, exerting a neuroprotective effect. We hypothesized that the combination of mild therapeutic hypothermia and adipose-derived stem cells would be neuroprotective for treatment of stroke. A rat model of transient middle cerebral artery occlusion was established using the nylon monofilament method. Mild therapeutic hypothermia(33°C) was induced after 2 hours of ischemia. Adipose-derived stem cells were administered through the femoral vein during reperfusion. The severity of neurological dysfunction was measured by a modified Neurological Severity Score Scaling System. The area of the infarct lesion was determined by 2,3,5-triphenyltetrazolium chloride staining. Apoptotic neurons were detected by terminal deoxynucleotidyl transferase-mediated d UTP-biotin nick end labeling(TUNEL) staining. The regeneration of microvessels and changes in the glial scar were detected by immunofluorescence staining. The inflammatory responses after ischemic brain injury were evaluated by in situ staining using markers of inflammatory cells. The expression of inflammatory cytokines was measured by reverse transcription-polymerase chain reaction. Compared with mild therapeutic hypothermia or adipose-derived stem cell treatment alone, their combination substantially improved neurological deficits and decreased infarct size. They synergistically reduced the number of TUNEL-positive cells and glial fibrillary acidic protein expression, increased vascular endothelial growth factor levels, effectively reduced inflammatory cell infiltration and down-regulated the m RNA expression of the proinflammatory cytokines interleukin-1β, tumor necrosis factor-α and interleukin-6. Our findings indicate that combined treatment is a better approach for treating stroke compared with mild therapeutic hypothermia or adipose-derived stem cells alone.Kai Zhao Rui Li Sheng Bi Yu Li Long Liu Yu-Long Jia Peng Han Chang-Cong Gu Xi-Ze Guo Wan-Ping Zhang Chun Wang Chun-Ying Pei Lin-Lu Tian Li-Xian Li 2018Neural Regeneration Research2018,13,10:9
12Multi-target tracking algorithm based on PHD filter against multi-range-false-target jamming显示文摘Multi-range-false-target(MRFT) jamming is particularly challenging for tracking radar due to the dense clutter and the repeated multiple false targets. The conventional association-based multi-target tracking(MTT) methods suffer from high computational complexity and limited usage in the presence of MRFT jamming.In order to solve the above problems, an efficient and adaptable probability hypothesis density(PHD) filter is proposed. Based on the gating strategy, the obtained measurements are firstly classified into the generalized newborn target and the existing target measurements. The two categories of measurements are independently used in the decomposed form of the PHD filter. Meanwhile,an amplitude feature is used to suppress the dense clutter. In addition, an MRFT jamming suppression algorithm is introduced to the filter. Target amplitude information and phase quantization information are jointly used to deal with MRFT jamming and the clutter by modifying the particle weights of the generalized newborn targets. Simulations demonstrate the proposed algorithm can obtain superior correct discrimination rate of MRFT, and high-accuracy tracking performance with high computational efficiency in the presence of MRFT jamming in the dense clutter.TIAN Chen PEI Yang HOU Peng ZHAO Qian 2020Journal of Systems Engineering and Electronics2020,31,5:9
13A flexible capacitive tactile sensor array with micro structure for robotic application显示文摘A flexible capacitive tactile sensor array with micro needle structure is proposed in this paper for robotic application.Micro needle layer made of polydimethylsiloxane(PDMS)is sandwiched between the upper electrode layer made of PDMS and the bottom electrode layer fabricated on polyester(PET)film.The PDMS material renders the device adequate flexibility as it can be rolled into a cylinder.The single cell size in the fabricated 4×4 sensors array is 0.7×0.5 cm2and the initial capacitance of each cell is 0.86 p F.The fabricated cell shows a sensitivity of 3.26%/m N within the full scale range of 1 k Pa.The micro needle structure gives better repeatability and stability.The maximum error during each measurement is about 3.2%,while the minimum error is about 1.2%.HU XiaoHui ZHANG Xu LIU Ming CHEN YuanFang LI Peng PEI WeiHua ZHANG Chun CHEN HongDa 2014Science China(Information Sciences)2014,57,12:9
14Pharmacokinetics of the prototype and hydrolyzed carboxylic forms of ginkgolides A, B, and K administered as a ginkgo diterpene lactones meglumine injection in beagle dogs显示文摘Ginkgo diterpene lactones meglumine injection(GDLI)is a commercially available product used for neuroprotection.However,the pharmacokinetic properties of the prototypes and hydrolyzed carboxylic forms of the primary components in GDLI,i.e.,ginkgolide A(GA),ginkgolide B(GB),and ginkgolide K(GK),have never been fully evaluated in beagle dogs.In this work,a simple,sensitive,and reliable method based on ultra-fast liquid chromatography-tandem mass spectrometry(UFLC-MS/MS)was developed,and the prototypes and total amounts of GA,GB,and GK were determined in beagle dog plasma.The plasma concentrations of the hydrolyzed carboxylic forms were calculated by subtracting the prototype concentrations from the total lactone concentrations.For the first time,the pharmacokinetics of GA,GB,and GK were fully assessed in three forms,i.e.,the prototypes,the hydrolyzed carboxylic forms,and the total amounts,after intravenous administration of GDLI in beagle dogs.It was shown that ginkgolides primarily existed in the hydrolyzed form in plasma,and the ratio of hydrolysates to prototype forms of GA and GB decreased gradually to a homeostatic ratio.All of the three forms of the three ginkgolides showed linear exposure of AUC to the dosages.GA,GB,and GK showed a constant half-life approximately 2.7,3.4,and 1.2 h,respectively,which were consistent for the forms at three dose levels(0.3,1.0,and 3.0 mg·kg^(-1))and after a consecutive injection of GDLI for 7 days(1.0 mg·kg^(-1)).WANG Shu-Yao A Ji-Ye FEI Fei GENG Jian-Liang PENG Ying OUYANG Bing-Chen WANG Pei JIN Xiao-Liang ZHAO Yu-Qing WANG Jian-Kun GENG Ting LI Yan-Jing HUA NG Wen-Zhe WANG Zhen-Zhong XIAO Wei WANG Guang-Ji 2017Chinese Journal of Natural Medicines2017,15,10:9
15A plasmonic route for the integrated wireless communication of subdiffraction-limited signals显示文摘Perfect lenses,superlenses and time-reversal mirrors can support and spatially separate evanescent waves,which is the basis for detecting subwavelength information in the far field.However,the inherent limitations of these methods have prevented the development of systems to dynamically distinguish subdiffraction-limited signals.Utilizing the physical merits of spoof surface plasmon polaritons(SPPs),we demonstrate that subdiffraction-limited signals can be transmitted on planar integrated SPP channels with low loss,low channel interference,and high gain and can be radiated with a very low environmental sensitivity.Furthermore,we show how deep subdiffraction-limited signals that are spatially coupled can be distinguished after line-of-sight wireless transmission.For a visualized demonstration,we realize the high-quality wireless communication of two movies on subwavelength channels over the line of sight in real time using our plasmonic scheme,showing significant advantages over the conventional methods.Hao Chi Zhang Le Peng Zhang Pei Hang He Jie Xu Cheng Qian Francisco J.Garcia-Vidal Tie Jun Cui 2020Light(Science & Applications)2020,9,1:8
16Implementation of an energy-efficient scheduling scheme based on pipeline flux leak monitoring networks显示文摘Flow against pipeline leakage and the pipe network sudden burst pipe to pipeline leakage flow for the application objects,an energy-efficient real-time scheduling scheme is designed extensively used in pipeline leak monitoring. The proposed scheme can adaptively adjust the network rate in real-time and reduce the cell loss rate,so that it can efficiently avoid the traffic congestion. The recent evolution of wireless sensor networks has yielded a demand to improve energy-efficient scheduling algorithms and energy-efficient medium access protocols. This paper proposes an energy-efficient real-time scheduling scheme that reduces power consumption and network errors on pipeline flux leak monitoring networks. The proposed scheme is based on a dynamic modulation scaling scheme which can scale the number of bits per symbol and a switching scheme which can swap the polling schedule between channels. Built on top of EDF scheduling policy,the proposed scheme enhances the power performance without violating the constraints of real-time streams. The simulation results show that the proposed scheme enhances fault-tolerance and reduces power consumption. Furthermore,that Network congestion avoidance strategy with an energy-efficient real-time scheduling scheme can efficiently improve the bandwidth utilization,TCP friendliness and reduce the packet drop rate in pipeline flux leak monitoring networks.ZHOU Peng YAO JiangHe PEI JiuLing 2009Science in China(Series F)2009,52,9:8
17An engraved artifact from Shuidonggou,an Early Late Paleolithic Site in Northwest China显示文摘Cognition and symbolic thinking are viewed as important features of modern human behavior.Engraved objects are seen as a hallmark of cognition and symbolism,and even as evidence for language.Accumulated evidences including engraved bones,ochre,ostrich eggshells and stone artifacts were unearthed from Africa,Europe,Levant even Siberia Paleolithic sites.But the archaeological evidence for this,including beads,ornaments,burials,performed objects and engraved objects,is rarely discovered in the Pleistocene of East Asia.The present paper reports an engraved stone object unearthed in the Early Late Paleolithic levels about 30 ka BP at the Shuidonggou site(SDG) in northwestern China.It was unearthed in the 1980's excavation from Lower culture unit of SDG1 but was identified in 2011 when the first author of this article observed the collection from the 1980's excavations stored in the Institute of Archaeology of Ningxia Hui Autonomous Region for further detailed lithic analysis.This lithic artifact is the first engraved non-organic object of the Paleolithic period found in China.In order to clarify the details of the incisions and to document the human intentional modifications,we used a KEYENCE VHX-600 Digital Microscope to measure and observe all the incisions in 3-dimensional perspective.Comparing the natural cracks and analyzing many details of the incisions,we argue that incisions on this stone artifact are the result of intentional behaviors by ancient humans.Also,we exclude the possible other causes including animal-induced damages,post-depositional phenomenon and unintentional by-products.Combining all these features,we suggest that the incisions were made by an intentional behavior and were probably of a non-utilitarian character.Because the nature of most other engraved objects in China is debate,we cannot get a clear scenario of the emergence and progress of modern human behavior in North China.But we infer the possible existence of a counting or recording system,or other symbolic behaviors,which reflect considerably evolved cognitive capacities or modern human behavior in the Early Late Paleolithic of East Asia.PENG Fei GAO Xing WANG HuiMin CHEN FuYou LIU DeCheng PEI ShuWen 2012Chinese Science Bulletin2012,57,35:8
18Accelerated degradation of HAP/PLLA bone scaffold by PGA blending facilitates bioactivity and osteoconductivity显示文摘The incorporation of hydroxyapatite(HAP)into poly-L-lactic acid(PLLA)matrix serving as bone scaffold is expected to exhibit bioactivity and osteoconductivity to those of the living bone.While too low degradation rate of HAP/PLLA scaffold hinders the activity because the embedded HAP in the PLLA matrix is difficult to contact and exchange ions with body fluid.In this study,biodegradable polymer poly(glycolic acid)(PGA)was blended into the HAP/PLLA scaffold fabricated by laser 3D printing to accelerate the degradation.The results indicated that the incorporation of PGA enhanced the degradation rate of scaffold as indicated by the weight loss increasing from 3.3%to 25.0%after immersion for 28 days,owing to the degradation of high hydrophilic PGA and the subsequent accelerated hydrolysis of PLLA chains.Moreover,a lot of pores produced by the degradation of the scaffold promoted the exposure of HAP from the matrix,which not only activated the deposition of bone like apatite on scaffold but also accelerated apatite growth.Cytocompatibility tests exhibited a good osteoblast adhesion,spreading and proliferation,suggesting the scaffold provided a suitable environment for cell cultivation.Furthermore,the scaffold displayed excellent bone defect repair capacity with the formation of abundant new bone tissue and blood vessel tissue,and both ends of defect region were bridged after 8 weeks of implantation.Cijun Shuai Wenjing Yang Pei Feng Shuping Peng Hao Pan 2021Bioactive Materials2021,6,2:8
19Deep Tectonic Processes and Superaccumulation of Metals Related to Granitoids in the Nanling MetaUogenic Province,China显示文摘The Nanling region is an important nonferrous and rare metal metallogenic province in South China, in which most of the deposits are related to granitoids in genesis. It covers southern Hunan, southern Jiangxi, Guangxi, Guangdong and Fujian provinces, with a total area of about 550,000 km2. This metallogenic province is well known in the world for its rich tungsten and tin resources. In the past 40-odd years, a vast amount of mineral exploration activities and studies of the geology of mineral deposits have been carried out and great achievements obtained in the province. This paper is focused on a discussion about the deep tectonic processes in the orogenic belt during the Mesozoic and their contribution to the superaccumulation of metals. Tectonically, this metallogenic province is composed of three units: (1) the marginal continental orogenic belt in the Southeastern Coast fold system in the Yanshanian; (2) the intercontinental orogenic belt in the collision suture belt between the Yangtze andPEI Rongfu, WANG Ping’an, and PENG Cong Institute of Mineral Deposits, CAGS, 26 Baiwanzhuang Rd., Beijing 100037 Institute of Geomechanics, CAGS, Beijing 100081 1999Acta Geologica Sinica(English Edition)1999,73,2:8
20Preliminary study on the living environment of hominids at the Donggutuo site,Nihewan Basin显示文摘The Donggutuo site, situated in the east margin of Nihewan basin, is one of the most important Paleolithic sites in China, characterized by the longest excavation seasons and the most abundant cultural remains recovered in the region. Based on well-constructed sporopollen, sediment grain size analysis, magnetic susceptibility, and iron oxide analysis of the 2000―2001 excavated section, four stages of environmental change in the Nihewan Beds are identified by the authors. The results indicate four major stages of environment and climate change from 1) warm and humid forest grass to 2) temperate and humid forest grass to 3) temperate and dry forest grass to 4) warm and humid forest, which is suitable for hominid occupation. The changes correspond to the stages of lake transgression and regression. The environment after the lake died out away has been cold and dry boschveld. The hominid activities at the site took place in the Early Pleistocene (1.10 Ma), which corresponds to the early three environmental stages. Therefore, it can be inferred that the early hominids adapted to the relatively low lake level episodes through activities involving sporadic stone tool making, procuring of raw materials for tools, concentrating stone artifacts, and hunting and butchering. In conclusion, the results will be of great significance to research regarding the relationship between hominid occupation and environmental changes as well as the adaptive behaviors of early humans at the Donggutuo site.PEI ShuWen LI XiaoLi LIU DeCheng MA Ning PENG Fei 2009Chinese Science Bulletin2009,54,21:7
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