The wild Lepista sordida is a kind of precious and rare edible fungus.An excellent strain of it by artificial domestication was obtained,which was high-yield and high in iron content.In this study,high-throughput comp...The wild Lepista sordida is a kind of precious and rare edible fungus.An excellent strain of it by artificial domestication was obtained,which was high-yield and high in iron content.In this study,high-throughput comparative proteomics was used to reveal the regulatory mechanism of its primordium differentiation in the early fruiting body formation.The mycelium before the primordium differentiation mainly expressed high levels of mitochondrial functional proteins and carbon dioxide concentration regulatory proteins.In young mushrooms,the highly expressed proteins were mainly involved in cell component generation,cell proliferation,nitrogen compound metabolism,nucleotide metabolism,glutathione metabolism,and purine metabolism.The differential regulation patterns of pileus and stipe growth to maturity were also revealed.The highly expressed proteins related to transcription,RNA splicing,the production of various organelles,DNA conformational change,nucleosome organization,protein processing,maturation and transport,and cell detoxification regulated the pileus development and maturity.The proteins related to carbohydrate and energy metabolism,large amounts of obsolete cytoplasmic parts,nutrient deprivation,and external stimuli regulated the stipe development and maturity.Multiple CAZymes regulated nutrient absorption,morphogenesis,spore production,stress response,and other life activities at different growth and development stages.展开更多
The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields o...The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on.展开更多
Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that ...Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that all the three natural popu-lations of the pine were high in genetic diversity but low in inter-population genetic differentiation. The proportion of polymorphic loci is 0.667, with each locus holding 2.13 alleles, averagely. The average expected and observed heterozygosity was 0.288 and 0.197, respectively. The gene differentiation among populations was 0.052, but the mean genetic distance was only 0.015.展开更多
The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K...The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.展开更多
Objective Psoriasis is an immune-mediated inflammatory disease.Despite advances in the study of its pathogenesis,the exact development mechanism of psoriasis remains to be fully elucidated.Hyperproliferative epidermis...Objective Psoriasis is an immune-mediated inflammatory disease.Despite advances in the study of its pathogenesis,the exact development mechanism of psoriasis remains to be fully elucidated.Hyperproliferative epidermis plays a crucial role in psoriasis.This study aimed to investigate the effects of interleukin-36β(IL-36β)on keratinocyte dysfunction in vitro.Methods Human keratinocyte cell lines,HaCaT cells,were treated with 0(control),50 or 100 ng/ml IL-36βrespectively for 24 h.Cell viability was determined with a cell counting kit-8 assay.Flow cytometry was used to assess the effects of IL-36βon apoptosis and cell cycle distribution.Expressions of the differentiation markers,such as keratin 10 and involucrin,were evaluated by quantitative real-time polymerase chain reaction(RT-qPCR).Expressions of the inflammatory cytokines,IL-1βand IL-6 were tested by ELISA.Results CCK8 assay showed the survival rate had no significant difference between the control and treated group(P>0.05).Flow cytometry analysis showed cell cycle arrest at S phase in the IL-36β-treated groups compared with the control group(P<0.05).RT-qPCR verified the decreased mRNA expressions of keratin 10 and involucrin in the IL-36β-treated groups compared with the negative control(P<0.01).ELISA showed 100 ng/ml IL-36βenhanced levels of IL-1βand IL-6 in culture supernatants of HaCaT cells compared with the negative control(P<0.05).Conclusion Taken together,these findings suggest that IL-36βcould induce cell cycle arrest at S phase,inhibit keratin 10 and involucrin expressions and promote inflammatory activity in HaCaT cell lines.展开更多
Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by ...Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX （F IX） gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay.Results The cell line bore a missense mutation in the 6th coding exon （c.676 C〉T） of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% （10/45） and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B.展开更多
Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple se...Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.展开更多
Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small ...Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073g/mL Percoll and propagated in the right cell culturing medium as previously described. The phenotypes of hMSCs were characterized with the use of flow cytometry. The hMSCs were cultured in cell culture medium (as control) and medium mixed with 5-aza for cellular differentiation. We examined by immunohistochemistry at 21 days the inducement of desmin, cardiac-specific cardiac troponin I (cTnI), GATA 4 and connexin-43 respectively. Results The hMSCs are fibroblast-like morphology and express CD44+ CD29+ CD90+ / CD34- CD45- CD31- CD11a. After 5-aza treatment, 20-30% hMSCs connected with adjoining cells and coalesced into myotube structures after 14days. Twenty-one days after 5-aza treatment, immunofluorescence showed that some cells expressed desmin,GATA4, cTnI and connexin-43 in 5,10 μmol/L 5-aza groups, but no cardiac specific protein was found in neither 3μmol/L 5-aza group nor in the control group. The ratio of cTnI positively stained cells in 10 μmol/L group was higher than that in 5 μmol/L group (65.3 ± 4.7% vs 48.2 ± 5.4%, P ＜ 0.05). Electron microscopy revealed that myofilaments were formed. The induced cells expressed cardiac-myosin heavy chain (MyHC) gene by reverse transcription-polymerase chain reaction (RT-PCR). Conclusions Theses findings suggest that hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration. (J Geriatr Cardiol 2004;1(2) :101-107. )展开更多
Objective To observe the expression profiles of osteoblast-related genes in human mesenchymal stem cells(MSCs) derived from bone marrow during osteogenic differentiation. Methods MSCs were induced to differentiate wit...Objective To observe the expression profiles of osteoblast-related genes in human mesenchymal stem cells(MSCs) derived from bone marrow during osteogenic differentiation. Methods MSCs were induced to differentiate with MSC osteogenic differentiation medium for 7, 14, 21 and 28 days respectively. Alizarin Red staining was used to detect matrix mineralization. Expression of osteoblast-related genes, including osteocalcin, osteopontin, Runt-related transcription factor 2(Runx2), alkaline phosphatase and collagen type Ⅰ, was assessed with quantitative reverse transcription-polymerase chain reaction. Results On day 14 after induction of differentiation, cells were stained positively with Alizarin Red. The expression levels of these genes exhibited an upward trend as induction time was prolonged. Exposure to osteogenic differentiation medium less than 21 days did not significantly induce osteocalcin expression; osteocalcin expression levels in the differentiated cells induced for 21 and 28 days were 1.63 and 2.46 times as high as the undifferentiated cells respectively(all P<0.05). Stimulation with MSC osteogenic differentiation medium over 14 days significantly enhanced bone marrow-derived MSCs to express osteopontin and Runx2 genes(all P<0.05). Osteogenic differentiation medium could significantly induce the expressions of alkaline phosphatase and collagen type Ⅰgenes(all P<0.05). Their expressions reached the peak levels on day 21, which were increased more than 4- and 3-fold respectively. Conclusion Human bone marrow-derived MSCs could exhibit the sequential expression pattern of osteoblast marker genes during osteogenic differentiation in vitro.展开更多
Genetic diversities and genetic differentiations of the four Pinus koraiensis populations （Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Hei...Genetic diversities and genetic differentiations of the four Pinus koraiensis populations （Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Heihe City, in China, and the suburb of Vladivostok City in Russia） were analyzed by using ISSR PCR technique. The results of 15 primers amplification showed that the ratio of polymorphic site of P koralensis population was 60.7%. Euch primer had 3.6 polymorphic sites, The diversity levels of the four P. koraiensis populations were rather higher compared with those of other Pinaceae species. The genetic diversity levels of t： koraiensis populations grown in the center region were higher than those grown in the edge zone. The genetic diversity of r3 koraiensis mainly came from the interiot of the population, accounting for 73% of total genetic diversity. There were no positive correlation between genetic distances and geographical distances for the four P koraiensis populations. The gradual decrease of natural distribution region of P. koraiensis was due to anthropic destroy and environmental factors （i.e. fire and wind throw）, rather than the lower genetic diversity.展开更多
We obtain several estimates of the essential norms of the products of differen- tiation operators and weighted composition operators between weighted Banach spaces of analytic functions with general weights. As applic...We obtain several estimates of the essential norms of the products of differen- tiation operators and weighted composition operators between weighted Banach spaces of analytic functions with general weights. As applications, we also give estimates of the es- sential norms of weighted composition operators between weighted Banach space of analytic functions and Bloch-type spaces.展开更多
With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to eva...With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy.展开更多
Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the prod...Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications.展开更多
Let L=-div(A▽) be a second order divergence form elliptic operator, where A is an accretive, n×n matrix with bounded measurable complex coefficients on R^n. Let L^α/2 (0 <α< 1) denotes the fractional dif...Let L=-div(A▽) be a second order divergence form elliptic operator, where A is an accretive, n×n matrix with bounded measurable complex coefficients on R^n. Let L^α/2 (0 <α< 1) denotes the fractional differential operator associated with L and (-△)^α/2b ∈ L^n/α(R^n). In this article, we prove that the commutator[b, L^α/2] is bounded from the homogenous Sobolev space Lα%2 (R^n) to L^2(R^n).展开更多
BackgroundGrowth differentiation factor （GDF）-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression o...BackgroundGrowth differentiation factor （GDF）-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression of heart failure （HF）. HF frequently develops after myocardial infarction （MI）, contributing to worse outcome. The aim of this study is to assess the correlation between GDF-15 levels and markers related to collagen turnover in different stages of HF.MethodsThe study consists of a cohort of 179 patients, including stable angina pectoris patients （AP group,n= 50）, old MI patients without HF （OMI group,n = 56）, old MI patients with HF （OMI-HF group,n= 38） and normal Control group （n = 35）. Both indicators reflecting the synthesis and degradation rates of collagen including precollagen I N-terminal peptide （PINP）, type I collagen carboxy-terminal peptide （ICTP）, precollagen III N-terminal peptide （PIIINP） and GDF-15 were measured using an enzyme-linked inmunosorbent assay.ResultsThe plasma GDF-15 level was higher in OMI-HF group （1373.4 ± 275.4 ng/L） than OMI group （1036.1 ± 248.6 ng/L）, AP group （784.6 ± 222.4 ng/L） and Control group （483.8 ± 186.4 ng/L） （P〈 0.001）. The indi-cators of collagen turnover （ICTP, PINP, PIIINP） all increased in the OMI-HF group compared with Control group （3.03 ± 1.02μg/Lvs. 2.08 ± 0.95μg/L, 22.2 ± 6.6μg/Lvs. 16.7 ± 5.1μg/L and 13.2 ± 7.9μg/Lvs. 6.4 ± 2.1μg/L, respectively;P〈 0.01）. GDF-15 positively cor-related with ICTP and PIIINP （r = 0.302,P〈 0.001 andr= 0.206,P= 0.006, respectively）. GDF-15 positively correlated to the echocardio-graphic diastolic indicators E/Em and left atrial pressure （r= 0.349 and r= 0.358, respectively;P〈 0.01）, and inversely correlated to the systolic indicators left ventricular ejection fraction and the average of peak systolic myocardial velocities （Sm） （r=-0.623 and r=-0.365, respectively;P〈 0.01）.ConclusionPlasma GDF-15 is associated with the indicators of type I and III collagen turnover.展开更多
Objective To investigate proliferation and differentiation of neural stem cells in adult rats after cerebral infarction. Methods Models of cerebral infarction in rats were made and the time-course expression of bromod...Objective To investigate proliferation and differentiation of neural stem cells in adult rats after cerebral infarction. Methods Models of cerebral infarction in rats were made and the time-course expression of bromodeoxyuridine(BrdU), Musashi1, glial fibrillary acidic protein (GFAP), and neuronal nuclear antigen (NeuN) were determined by immunohistochemistry and immunofluorescence staining. BrdU and Musashi1 were used to mark dividing neural stem cells. GFAP and NeuN were used to mark differentiating neural stem cells. Results Compared with controls, the number of BrdU-labeled and BrdU-labeled with Musashi1-positive cells incre-ased strikingly 1 day after cerebral infarction; approximately 6 fold with a peak 7 days later; markedly decreased 14 days later, but was still elevated compared with that of controls; decling to the control level 28 days later. The number of BrdU-labeled with GFAP-positive cells nearly remained unchanged in the hippocampus after cerebral infarction. The nu-mber of BrdU-labeled with NeuN-positive cells increased strikingly 14 days after cerebral infarction, reached maximum peak in the hippocampus 28 days after cerebral infarction in rats. Conclusion Cerebral infarction stimulate proliferation of inherent neural stem cells and most proliferated neural stem cells differentiate into neurons.展开更多
We characterize boundedness and compactness of products of differentiation op- erators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bl...We characterize boundedness and compactness of products of differentiation op- erators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bloch spaces with general weights.展开更多
Picea mongolica W. D. Xu is an endemic and endangered species which is only found in semi-arid areas of northern China. It has been widely used as an afforestation tree in the establishment of the Three-North Shelterb...Picea mongolica W. D. Xu is an endemic and endangered species which is only found in semi-arid areas of northern China. It has been widely used as an afforestation tree in the establishment of the Three-North Shelterbelt System for its adaptation to arid soils and as a virescent tree in urban gardens and streets for its beautiful shape. Due to different microenvironments, P. mongolica populations may differentiate into many ecological groups with different adaptive abilities. Long-term adaptation to a dry environment makes P. mongolica differentiate into different ecotypes. Typical ecotypes are P. mongolica f. purpurea （Fp）, P. mongolica f. rubra （Fr） and P. mongolica f. viridis （Fv）. Our results show that cone size is clearly not uniform among different ecotypes; the largest cones are found in the Fv ecotype and the smallest in Fp. There were also distinct differences between these ecotypes in terms of height and length of squama. At the molecular level, the zymograms of peroxidase and lipase prove the existence of different ecotypes in P. mongolica. The results are useful for investigating and managing this rare spruce species in China.展开更多
periodontal ligament stem cells; aging; proliferation; osteogenic differentiation Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells...periodontal ligament stem cells; aging; proliferation; osteogenic differentiation Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells （PDLSC） derived from different aged donors, and to evaluate the effects of aging on the biological characteristics of PDLSC. Methods Periodontal ligament tissues were obtained from 24 surgically extracted human premolars during orthodontics therapy. The specimens were divided into three groups according to the donor’s age. Group A： 18-20 years, group B： 30-35 years, group C： 45-50 years. PDLSC were isolated and cultured using a tissue-block-based enzymolytic method by limiting dilution assay. The colony forming efficiency of PDLSC for three experimental groups was determined. Senescence-Associated β-Galactosidase （SA-β-G） expression in the three groups was examined using β-galactosidase staining working solution. Cell cycle and apoptosis of the PDLSC were examined by the flow cytometry. Alkaline phosphatase （ALP） activity was evaluated by ALP staining. The expression of osteoplastic differentiation related genes Runt-related transcription factor-2 （Runx-2）, Collagen Type 1 （col-1）, and ALP of PDLSC were examined by quantitative real-time RT-PCR. Results The colony forming efficiency of PDLSC in Group A, B and C was 36.67%, 22.67% and 9.33%, respectively, which decreased with donors’ age （P〈0.05）. SA-β-G expression of the senescent PDLSC in group A, B and C were 4.14%, 16.39%, 50.38%, respectively （P〈0.05）. Cells in G2/S phase was 38.73%, 29.88%, 18.25% （P〈0.05）, and the apoptosis rate was 1.57%, 4.56%, 5.84% （P〈0.05）, in group A, B and C respectively. The ALP staining in the three groups decreased with the increase of donors’ ages, and the expression of Runx-2, col-1 and ALP decreased gradually from group A to group C （all P〈0.05）, which indicated the osteogenic differentiation capacity of PDLSC decreased while donor aging. Conclusion Human PDLSC could be successfully isolated from periodontal ligament tissues of different aged donors. However, the proliferation and osteogenic differentiation capacity of PDLSC decreased while donor aging.展开更多
We experimentally demonstrate the recognition of positional isomers of propyl alcohol vapor through nonlinear fluorescence induced by high-intensity femtosecond laser filaments in air. By measuring characteristic fluo...We experimentally demonstrate the recognition of positional isomers of propyl alcohol vapor through nonlinear fluorescence induced by high-intensity femtosecond laser filaments in air. By measuring characteristic fluorescence of n-propyl and isopropyl alcohol vapors produced by femtosecond filament excitation, it is found that they show identical spectra, that is, those from molecular bands of CH, C2, Nit, OH and CN, while the relative intensities are different. By comparing the ratios of the CH and C2 signals, the two propyl alcohol isomers are differentiated. The different signal intensities are ascribed to different ionization potentials of the two isomer molecules, leading to different production efficiencies of fluorescing fragments.展开更多
基金funded by the Shandong Edible Fungus Agricultural Technology System(SDAIT-07-02)the National Natural Science Foundation of China(Grant No.32000041 and 32272789)+2 种基金the Shandong Provincial Natural Science Foundation,China(ZR2020QC005)the Qingdao Agricultural University Scientific Research Foundation(6631120076)horizontal project:Breeding and property protection of new varieties of factory produced Hypsizygus marmoreus(20183702012614).
文摘The wild Lepista sordida is a kind of precious and rare edible fungus.An excellent strain of it by artificial domestication was obtained,which was high-yield and high in iron content.In this study,high-throughput comparative proteomics was used to reveal the regulatory mechanism of its primordium differentiation in the early fruiting body formation.The mycelium before the primordium differentiation mainly expressed high levels of mitochondrial functional proteins and carbon dioxide concentration regulatory proteins.In young mushrooms,the highly expressed proteins were mainly involved in cell component generation,cell proliferation,nitrogen compound metabolism,nucleotide metabolism,glutathione metabolism,and purine metabolism.The differential regulation patterns of pileus and stipe growth to maturity were also revealed.The highly expressed proteins related to transcription,RNA splicing,the production of various organelles,DNA conformational change,nucleosome organization,protein processing,maturation and transport,and cell detoxification regulated the pileus development and maturity.The proteins related to carbohydrate and energy metabolism,large amounts of obsolete cytoplasmic parts,nutrient deprivation,and external stimuli regulated the stipe development and maturity.Multiple CAZymes regulated nutrient absorption,morphogenesis,spore production,stress response,and other life activities at different growth and development stages.
基金the Natural Science Foundation of Heilongjiang Province (C9726).
文摘The Random Amplified Polymorphism DNA (RAPD) markers were used to stu dy the intra-specific diversity and regional differentiation of the Chinese fore st frogs (Rana chensinensis), which were sampled from the fields of 8 regions in Heilongjiang Province. Totally 78 polymorphic DNA loci were amplified by 10 RAP D primers. By genetic distance analysis and phylogenetic tree reconstruction wit h the Neighbor-Joining (NJ) method the results showed that the populations of Ch inese forest frogs distributed in 8 regions existed great differentiation (Avera ge Fst=0.347, SD=0.235) while there was the paradox between geographic distances and genetic distances. Based on geographic and geological data, a hypothesis wa s posed that it is very possible that the hilly lands in the downstream of the S onghua River and the Heilong River were the center of the origin of the Chinese forest frogs in Heilongjiang Province. And mainly through the Songhua River syst em, the Chinese forest frogs dispersed into the Songneng Plain from the Sanjiang Plain whereas the Fangzheng region became a sub-center for the western dispersi on.
基金his article was supported by the Natural Science Founda-tion of Yunnan Province (No.98C017Q).
文摘Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that all the three natural popu-lations of the pine were high in genetic diversity but low in inter-population genetic differentiation. The proportion of polymorphic loci is 0.667, with each locus holding 2.13 alleles, averagely. The average expected and observed heterozygosity was 0.288 and 0.197, respectively. The gene differentiation among populations was 0.052, but the mean genetic distance was only 0.015.
文摘The genetic diversity and population structure of the Dybowski＇s frog（Rana dybowskii） were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity（HE） was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient（FST） showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains（p〈0.001）.This result was verified further by Nei＇s genetic distance（DA） based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units（MUs） for their protection and management.
基金Supported by the National Natural Science Foundation of China(No.81773331)CAMS Initiative for Innovative Medicine(No.2017-I2M-B&R-01)
文摘Objective Psoriasis is an immune-mediated inflammatory disease.Despite advances in the study of its pathogenesis,the exact development mechanism of psoriasis remains to be fully elucidated.Hyperproliferative epidermis plays a crucial role in psoriasis.This study aimed to investigate the effects of interleukin-36β(IL-36β)on keratinocyte dysfunction in vitro.Methods Human keratinocyte cell lines,HaCaT cells,were treated with 0(control),50 or 100 ng/ml IL-36βrespectively for 24 h.Cell viability was determined with a cell counting kit-8 assay.Flow cytometry was used to assess the effects of IL-36βon apoptosis and cell cycle distribution.Expressions of the differentiation markers,such as keratin 10 and involucrin,were evaluated by quantitative real-time polymerase chain reaction(RT-qPCR).Expressions of the inflammatory cytokines,IL-1βand IL-6 were tested by ELISA.Results CCK8 assay showed the survival rate had no significant difference between the control and treated group(P>0.05).Flow cytometry analysis showed cell cycle arrest at S phase in the IL-36β-treated groups compared with the control group(P<0.05).RT-qPCR verified the decreased mRNA expressions of keratin 10 and involucrin in the IL-36β-treated groups compared with the negative control(P<0.01).ELISA showed 100 ng/ml IL-36βenhanced levels of IL-1βand IL-6 in culture supernatants of HaCaT cells compared with the negative control(P<0.05).Conclusion Taken together,these findings suggest that IL-36βcould induce cell cycle arrest at S phase,inhibit keratin 10 and involucrin expressions and promote inflammatory activity in HaCaT cell lines.
基金Supported by the National Science and Technology Major Project(2011ZX09102-010-04)
文摘Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX （F IX） gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay.Results The cell line bore a missense mutation in the 6th coding exon （c.676 C〉T） of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% （10/45） and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B.
基金supported by the Cooperative Research Program for Agriculture Science & Technology Development(Project no.PJ01117902) of the National Institute of Horticultural and Herbal Science,RDA,Republic of Koreathe Ministry of Education,People’s Republic of China(Program No.MS2012DBLY017 for Foreign Distinguished Scientists of the Ministry of Education)the Research Foundation of Kangwon National University,Republic of Korea
文摘Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.
基金supported by research grants from State 863 high technology R&D Project of China(2002AA205051and 2003AA205160)the National Key Rroject for Basic Research of China(2001CB509906)
文摘Objective To investigate the potential of adult mesenchymal stem cells (MSCs) derived from human bone marrow to undergo cardiomyogenic differentiation after exposure to 5-azacytidine (5-aza) in vitro. Methods A small bone marrow aspirate was taken from the iliac crest of human volunteers, and hMSCs were isolated by 1.073g/mL Percoll and propagated in the right cell culturing medium as previously described. The phenotypes of hMSCs were characterized with the use of flow cytometry. The hMSCs were cultured in cell culture medium (as control) and medium mixed with 5-aza for cellular differentiation. We examined by immunohistochemistry at 21 days the inducement of desmin, cardiac-specific cardiac troponin I (cTnI), GATA 4 and connexin-43 respectively. Results The hMSCs are fibroblast-like morphology and express CD44+ CD29+ CD90+ / CD34- CD45- CD31- CD11a. After 5-aza treatment, 20-30% hMSCs connected with adjoining cells and coalesced into myotube structures after 14days. Twenty-one days after 5-aza treatment, immunofluorescence showed that some cells expressed desmin,GATA4, cTnI and connexin-43 in 5,10 μmol/L 5-aza groups, but no cardiac specific protein was found in neither 3μmol/L 5-aza group nor in the control group. The ratio of cTnI positively stained cells in 10 μmol/L group was higher than that in 5 μmol/L group (65.3 ± 4.7% vs 48.2 ± 5.4%, P ＜ 0.05). Electron microscopy revealed that myofilaments were formed. The induced cells expressed cardiac-myosin heavy chain (MyHC) gene by reverse transcription-polymerase chain reaction (RT-PCR). Conclusions Theses findings suggest that hMSCs from adult bone marrow can be differentiated into cardiac-like muscle cells with 5-aza inducement in vitro and the differentiation is in line with the 5-aza concentration. (J Geriatr Cardiol 2004;1(2) :101-107. )
基金Supported by the National Natural Science Foundation of China(81372007)
文摘Objective To observe the expression profiles of osteoblast-related genes in human mesenchymal stem cells(MSCs) derived from bone marrow during osteogenic differentiation. Methods MSCs were induced to differentiate with MSC osteogenic differentiation medium for 7, 14, 21 and 28 days respectively. Alizarin Red staining was used to detect matrix mineralization. Expression of osteoblast-related genes, including osteocalcin, osteopontin, Runt-related transcription factor 2(Runx2), alkaline phosphatase and collagen type Ⅰ, was assessed with quantitative reverse transcription-polymerase chain reaction. Results On day 14 after induction of differentiation, cells were stained positively with Alizarin Red. The expression levels of these genes exhibited an upward trend as induction time was prolonged. Exposure to osteogenic differentiation medium less than 21 days did not significantly induce osteocalcin expression; osteocalcin expression levels in the differentiated cells induced for 21 and 28 days were 1.63 and 2.46 times as high as the undifferentiated cells respectively(all P<0.05). Stimulation with MSC osteogenic differentiation medium over 14 days significantly enhanced bone marrow-derived MSCs to express osteopontin and Runx2 genes(all P<0.05). Osteogenic differentiation medium could significantly induce the expressions of alkaline phosphatase and collagen type Ⅰgenes(all P<0.05). Their expressions reached the peak levels on day 21, which were increased more than 4- and 3-fold respectively. Conclusion Human bone marrow-derived MSCs could exhibit the sequential expression pattern of osteoblast marker genes during osteogenic differentiation in vitro.
文摘Genetic diversities and genetic differentiations of the four Pinus koraiensis populations （Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Heihe City, in China, and the suburb of Vladivostok City in Russia） were analyzed by using ISSR PCR technique. The results of 15 primers amplification showed that the ratio of polymorphic site of P koralensis population was 60.7%. Euch primer had 3.6 polymorphic sites, The diversity levels of the four P. koraiensis populations were rather higher compared with those of other Pinaceae species. The genetic diversity levels of t： koraiensis populations grown in the center region were higher than those grown in the edge zone. The genetic diversity of r3 koraiensis mainly came from the interiot of the population, accounting for 73% of total genetic diversity. There were no positive correlation between genetic distances and geographical distances for the four P koraiensis populations. The gradual decrease of natural distribution region of P. koraiensis was due to anthropic destroy and environmental factors （i.e. fire and wind throw）, rather than the lower genetic diversity.
文摘We obtain several estimates of the essential norms of the products of differen- tiation operators and weighted composition operators between weighted Banach spaces of analytic functions with general weights. As applications, we also give estimates of the es- sential norms of weighted composition operators between weighted Banach space of analytic functions and Bloch-type spaces.
基金supported in part by the National Key R&D Program of China (No.2017YFE0109000)the project of China Datang Corporation Ltd
文摘With the increasing proportion of wind power integration, the volatility of wind power brings huge challenges to the safe and stable operation of the electric power system. At present, the indexes commonly used to evaluate the volatility of wind power only consider its overall characteristics, such as the standard deviation of wind power, the average of power variables, etc., while ignoring the detailed volatility of wind power, that is, the features of the frequency distribution of power variables. However, how to accurately describe the detailed volatility of wind power is the key foundation to reduce its adverse influences. To address this, a quantitative method for evaluating the detailed volatility of wind power at multiple temporal-spatial scales is proposed. First, the volatility indexes which can evaluate the detailed fluctuation characteristics of wind power are presented, including the upper confidence limit, lower confidence limit and confidence interval of power variables under the certain confidence level. Then, the actual wind power data from a location in northern China is used to illustrate the application of the proposed indexes at multiple temporal(year–season–month–day) and spatial scales(wind turbine–wind turbines–wind farm–wind farms) using the calculation time windows of 10 min, 30 min, 1 h, and 4 h. Finally, the relationships between wind power forecasting accuracy and its corresponding detailed volatility are analyzed to further verify the effectiveness of the proposed indexes. The results show that the proposed volatility indexes can effectively characterize the detailed fluctuations of wind power at multiple temporal-spatial scales. It is anticipated that the results of this study will serve as an important reference for the reserve capacity planning and optimization dispatch in the electric power system which with a high proportion of renewable energy.
基金partially supported by the Australian Research Council (DP160103116)CSIRO’s OCE Science Leadership Schemethe scholarship support from the National Council for Science and Technology Development (CNPq-Brasil)
文摘Nanostructured graphene films were used as platforms for the differentiation of Saos-2 cells into bonelike cells. The films were grown using the plasma-enhanced chemical vapor deposition method, which allowed the production of both vertically and horizontally aligned carbon nanowalls(CNWs). Modifications of the techniqueallowed control of the density of the CNWs and their orientation after the transfer process. The influence of two different topographies on cell attachment, proliferation,and differentiation was investigated. First, the transferred graphene surfaces were shown to be noncytotoxic and were able to support cell adhesion and growth for over 7 days.Second, early cell differentiation(identified by cellular alkaline phosphatase release) was found to be enhanced on the horizontally aligned CNW surfaces, whereas mineralization(identified by cellular calcium production), a later stage of bone cell differentiation, was stimulated by the presence of the vertical CNWs on the surfaces. These results show that the graphene coatings, grown using the presented method, are biocompatible. And their topographies have an impact on cell behavior, which can be useful in tissue engineering applications.
基金supported by NSFC(11471033),NCET of China(NCET-11-0574)the Fundamental Research Funds for the Central Universities(FRF-BR-16-011A)
文摘Let L=-div(A▽) be a second order divergence form elliptic operator, where A is an accretive, n×n matrix with bounded measurable complex coefficients on R^n. Let L^α/2 (0 <α< 1) denotes the fractional differential operator associated with L and (-△)^α/2b ∈ L^n/α(R^n). In this article, we prove that the commutator[b, L^α/2] is bounded from the homogenous Sobolev space Lα%2 (R^n) to L^2(R^n).
基金All authors have no conflict of interest regarding this paper. This work was supported by Grant National Natural Science Foundation of China （81400262） ＆ Backbone Fund of Peking University Third Hospital.
文摘BackgroundGrowth differentiation factor （GDF）-15, a divergent member of the transforming growth factor beta super-family does appear to be up-regulated in response to experimental pressure overload and progression of heart failure （HF）. HF frequently develops after myocardial infarction （MI）, contributing to worse outcome. The aim of this study is to assess the correlation between GDF-15 levels and markers related to collagen turnover in different stages of HF.MethodsThe study consists of a cohort of 179 patients, including stable angina pectoris patients （AP group,n= 50）, old MI patients without HF （OMI group,n = 56）, old MI patients with HF （OMI-HF group,n= 38） and normal Control group （n = 35）. Both indicators reflecting the synthesis and degradation rates of collagen including precollagen I N-terminal peptide （PINP）, type I collagen carboxy-terminal peptide （ICTP）, precollagen III N-terminal peptide （PIIINP） and GDF-15 were measured using an enzyme-linked inmunosorbent assay.ResultsThe plasma GDF-15 level was higher in OMI-HF group （1373.4 ± 275.4 ng/L） than OMI group （1036.1 ± 248.6 ng/L）, AP group （784.6 ± 222.4 ng/L） and Control group （483.8 ± 186.4 ng/L） （P〈 0.001）. The indi-cators of collagen turnover （ICTP, PINP, PIIINP） all increased in the OMI-HF group compared with Control group （3.03 ± 1.02μg/Lvs. 2.08 ± 0.95μg/L, 22.2 ± 6.6μg/Lvs. 16.7 ± 5.1μg/L and 13.2 ± 7.9μg/Lvs. 6.4 ± 2.1μg/L, respectively;P〈 0.01）. GDF-15 positively cor-related with ICTP and PIIINP （r = 0.302,P〈 0.001 andr= 0.206,P= 0.006, respectively）. GDF-15 positively correlated to the echocardio-graphic diastolic indicators E/Em and left atrial pressure （r= 0.349 and r= 0.358, respectively;P〈 0.01）, and inversely correlated to the systolic indicators left ventricular ejection fraction and the average of peak systolic myocardial velocities （Sm） （r=-0.623 and r=-0.365, respectively;P〈 0.01）.ConclusionPlasma GDF-15 is associated with the indicators of type I and III collagen turnover.
基金Supported by the Early-stage Special Fund for Important Basis Rese-arch Project from the Technology Department of China (2002CCAO4400)
文摘Objective To investigate proliferation and differentiation of neural stem cells in adult rats after cerebral infarction. Methods Models of cerebral infarction in rats were made and the time-course expression of bromodeoxyuridine(BrdU), Musashi1, glial fibrillary acidic protein (GFAP), and neuronal nuclear antigen (NeuN) were determined by immunohistochemistry and immunofluorescence staining. BrdU and Musashi1 were used to mark dividing neural stem cells. GFAP and NeuN were used to mark differentiating neural stem cells. Results Compared with controls, the number of BrdU-labeled and BrdU-labeled with Musashi1-positive cells incre-ased strikingly 1 day after cerebral infarction; approximately 6 fold with a peak 7 days later; markedly decreased 14 days later, but was still elevated compared with that of controls; decling to the control level 28 days later. The number of BrdU-labeled with GFAP-positive cells nearly remained unchanged in the hippocampus after cerebral infarction. The nu-mber of BrdU-labeled with NeuN-positive cells increased strikingly 14 days after cerebral infarction, reached maximum peak in the hippocampus 28 days after cerebral infarction in rats. Conclusion Cerebral infarction stimulate proliferation of inherent neural stem cells and most proliferated neural stem cells differentiate into neurons.
基金supported by SQU Grant No.IG/SCI/DOMS/16/12The second author was partially supported by NSFC(11720101003)the Project of International Science and Technology Cooperation Innovation Platform in Universities in Guangdong Province(2014KGJHZ007)
文摘We characterize boundedness and compactness of products of differentiation op- erators and weighted composition operators between weighted Banach spaces of analytic functions and weighted Zygmund spaces or weighted Bloch spaces with general weights.
基金the financial support from the National Nature Science Foundation of China (NSFC) under Grant Nos. 39900019, 30070129 and 30670315the Global Environmental Research Fund of the Ministry of the Environment of Japan
文摘Picea mongolica W. D. Xu is an endemic and endangered species which is only found in semi-arid areas of northern China. It has been widely used as an afforestation tree in the establishment of the Three-North Shelterbelt System for its adaptation to arid soils and as a virescent tree in urban gardens and streets for its beautiful shape. Due to different microenvironments, P. mongolica populations may differentiate into many ecological groups with different adaptive abilities. Long-term adaptation to a dry environment makes P. mongolica differentiate into different ecotypes. Typical ecotypes are P. mongolica f. purpurea （Fp）, P. mongolica f. rubra （Fr） and P. mongolica f. viridis （Fv）. Our results show that cone size is clearly not uniform among different ecotypes; the largest cones are found in the Fv ecotype and the smallest in Fp. There were also distinct differences between these ecotypes in terms of height and length of squama. At the molecular level, the zymograms of peroxidase and lipase prove the existence of different ecotypes in P. mongolica. The results are useful for investigating and managing this rare spruce species in China.
基金Supported by National Natural Science Foundation of China（51473175）, Science and Technology Nova Plan of Beijing City（Z141107001814101）.
文摘periodontal ligament stem cells; aging; proliferation; osteogenic differentiation Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells （PDLSC） derived from different aged donors, and to evaluate the effects of aging on the biological characteristics of PDLSC. Methods Periodontal ligament tissues were obtained from 24 surgically extracted human premolars during orthodontics therapy. The specimens were divided into three groups according to the donor’s age. Group A： 18-20 years, group B： 30-35 years, group C： 45-50 years. PDLSC were isolated and cultured using a tissue-block-based enzymolytic method by limiting dilution assay. The colony forming efficiency of PDLSC for three experimental groups was determined. Senescence-Associated β-Galactosidase （SA-β-G） expression in the three groups was examined using β-galactosidase staining working solution. Cell cycle and apoptosis of the PDLSC were examined by the flow cytometry. Alkaline phosphatase （ALP） activity was evaluated by ALP staining. The expression of osteoplastic differentiation related genes Runt-related transcription factor-2 （Runx-2）, Collagen Type 1 （col-1）, and ALP of PDLSC were examined by quantitative real-time RT-PCR. Results The colony forming efficiency of PDLSC in Group A, B and C was 36.67%, 22.67% and 9.33%, respectively, which decreased with donors’ age （P〈0.05）. SA-β-G expression of the senescent PDLSC in group A, B and C were 4.14%, 16.39%, 50.38%, respectively （P〈0.05）. Cells in G2/S phase was 38.73%, 29.88%, 18.25% （P〈0.05）, and the apoptosis rate was 1.57%, 4.56%, 5.84% （P〈0.05）, in group A, B and C respectively. The ALP staining in the three groups decreased with the increase of donors’ ages, and the expression of Runx-2, col-1 and ALP decreased gradually from group A to group C （all P〈0.05）, which indicated the osteogenic differentiation capacity of PDLSC decreased while donor aging. Conclusion Human PDLSC could be successfully isolated from periodontal ligament tissues of different aged donors. However, the proliferation and osteogenic differentiation capacity of PDLSC decreased while donor aging.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61427816 and 61235003the Research Fund for the Doctoral Program of Higher Education of China under Grant No 20130061110047the Open Fund of the State Key Laboratory of High Field Laser Physics
文摘We experimentally demonstrate the recognition of positional isomers of propyl alcohol vapor through nonlinear fluorescence induced by high-intensity femtosecond laser filaments in air. By measuring characteristic fluorescence of n-propyl and isopropyl alcohol vapors produced by femtosecond filament excitation, it is found that they show identical spectra, that is, those from molecular bands of CH, C2, Nit, OH and CN, while the relative intensities are different. By comparing the ratios of the CH and C2 signals, the two propyl alcohol isomers are differentiated. The different signal intensities are ascribed to different ionization potentials of the two isomer molecules, leading to different production efficiencies of fluorescing fragments.
