The genetic diversity of the populations for 14 wild green peafowls (Pavo muticus) and 18 captive green pea-fowls was investigated by using the technology of random amplified polymorphic DNA (RAPD). Totally 161 and 16...The genetic diversity of the populations for 14 wild green peafowls (Pavo muticus) and 18 captive green pea-fowls was investigated by using the technology of random amplified polymorphic DNA (RAPD). Totally 161 and 166 ampli-fied bands were obtained by using 23 arbitrary primers to amplify the genomic DNA of wild and captive green peafowls re-spectively. The results showed that the average relative genetic distance of the wild and captive green peafowls popula-tions was 0.0555 and 0.1355, respectively, and difference of the average relative genetic distances between the two popu-lations was 0.1635. The Shannon diversity index for the wild and captive green peafowl populations was 0.4348 and 1.0163, respectively, which means that there exists significant difference in genetic diversity between the two populations, and the genetic diversity of wild green peafowl was low. The two populations originated from two different families according to analysis by the UPGMA method. This research can provide the theoretical basis for supervising genealogies management of peafowl populations.展开更多
The current Internet has evolved during the last decade to a global provider of diverse applications. However, the underlying structure of routing and addressing has not evolved in the same pace and is somewhat inflex...The current Internet has evolved during the last decade to a global provider of diverse applications. However, the underlying structure of routing and addressing has not evolved in the same pace and is somewhat inflexible. How to provide diverse routing services, support emerging communication paradigms based on limited and definite network resources has become an urgent challenge. This paper investigates the adaptive matching between routing and application through network function decomposition and composition, and proposes a polymorphic routing model to support diverse applications and emerging communication paradigms. The model splits complex routing functions into its constituents, and derives customized routing mechanisms supporting various applications by composing the routing constituents. The derivation process is modeled as a Markov Decision Process (MDP), and a polymorphic derivation algorithm is also proposed to derive customized routing instances for diverse applications. The model enables the network to self-adjust routing services dynamically to adapt to the different requirements of applications, supports coexistence of multiple routing modes and communication paradigms, and provides a feasible solution for the network compatibility and evolvement. We describe the key design and demonstrate the feasibility of polymorphic derivation by simulations. We also present case studies that demonstrate key functionalities the polymorphic routing model enables.展开更多
The high-pressure polymorphs and structural transformation of Sn were experimentally investigated using angle- dispersive synchrotron x-ray diffraction up to 108.9 GPa. The results show that at least at 12.8 GPa β-Sn...The high-pressure polymorphs and structural transformation of Sn were experimentally investigated using angle- dispersive synchrotron x-ray diffraction up to 108.9 GPa. The results show that at least at 12.8 GPa β-Sn→bct structure transformation was completed and no two-phase coexistence was found. By using a long-wavelength x-ray, we resolved the diffraction peaks splitting and discovered the formation of a new distorted orthorhombic structure bco from the bct structure at 31.8 GPa. The variation of the lattice parameters and their ratios with pressure further validate the observation of the bco polymorph. The bcc structure appears at 40.9 GPa and coexists with the bco phase throughout a wide pressure range of 40.9 GPa-73.1 GPa. Above 73.1 GPa, only the bcc polymorph is observed, The systematically experimental investigation confirms the phase transition sequence of Sn asβ-Sn→bct→bco→bco ＋ bcc→bcc upon compression to 108.9 GPa at room temperature.展开更多
In this work, comprehensive studies of 2,4-dinitroanisole(2,4DNAN) were carried out using powder thermorentgenography of the internal standard. The time of the complete polymorphic transition in the solid phase β→a ...In this work, comprehensive studies of 2,4-dinitroanisole(2,4DNAN) were carried out using powder thermorentgenography of the internal standard. The time of the complete polymorphic transition in the solid phase β→a in 2,4DNAN under various combinations of conditions has been determined. It has been established that, regardless of the season of manufacture of the substance, when it is stored for 8-9months, with a change in ambient temperature from minus 30℃ to plus 30℃, a complete polymorphic transition β→a occurs. When stored in conditions below minus 5℃, polymorphic transition does not occur. When stored in conditions above plus 30℃ in a closed container, polymorphic transition occurs within 3 weeks. The polymorphic transition is accompanied by a decrease in density by 1.3%-1.5% and an increase in melting temperature by 10-12℃, depending on the degree of purity of the starting substance. The activation energy of the molecular rearrangement was 68-70 k J/mol(16.5 ± 3 kcal/mol). The mechanism of polymorphic transition has been evaluated, which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the product. The average activation energy of the polymorphic transition process was 110 ± 6.2 k J/mol(26.2 kcal/mol). In an open container, reactions proceed by a homogeneous mechanism, and in a closed container by a heterogeneous mechanism involving the gas phase.展开更多
To investigate the levels of polymorphisms and Mendelian segregation ratio in clone “TB01” (P. tomentosa×P. bolleana) ×clone “LM50” (P. tomentosa) BC 1 population at the entire genome level, ampl...To investigate the levels of polymorphisms and Mendelian segregation ratio in clone “TB01” (P. tomentosa×P. bolleana) ×clone “LM50” (P. tomentosa) BC 1 population at the entire genome level, amplified fragment length polymorphisms (AFLPs) analysis was conducted for both parents and 120 progenies. Forty one pairs of selective primers were used to detect 2?707 bands, of which 712 (26.4%) were polymorphic. Chi\|square tests were performed to examine if the observed genotypic frequencies of AFLP loci deviated from expected 1∶1 Mendelian segregation ratio ( P <0.01) in BC 1 population. Among the 712 loci 571 (80.2%) fit to Mendelian 1∶1 segregation ratio, corresponding to DNA polymorphisms heterozygous in one parent and a null in the other. The result shows that the AFLP markers are very suitable for fingerprinting and genetic mapping in the Chinese white poplar (Populus tomentosa Carr.).展开更多
The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragm...The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA （RAPD） technique. In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors, and a correlative segment BFLR-16 was obtained. The correlation coefficient between BFLI-16 and FLT was 0.6144, with the significant level of 1%. BFLI-16 was then cloned, sequenced and transformed into SCAR marker. The percentage of identifying long fiber birches by this SCAR was more than 92. The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length, and its existence is significantly correlative with the increase in the fiber length.展开更多
Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAP...Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions （SCAR） marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex （MHC） class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference （p〈0.01） in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.展开更多
Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic div...Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for T.wallichiana, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.展开更多
This study was conducted to determine the parent-off spring genetic structure of the pedunculate oak(Quercus robur L.),sessile oak(Q.petraea[Matt.]Liebl.)and their hybrids.Forty half-sib Quercus families and their mat...This study was conducted to determine the parent-off spring genetic structure of the pedunculate oak(Quercus robur L.),sessile oak(Q.petraea[Matt.]Liebl.)and their hybrids.Forty half-sib Quercus families and their maternal trees originating from one tree stand in southern Lithuania were analyzed using SSR and RAPD markers.Based on a preliminary study of leaf morphological traits,the individuals separated into six groups.The studied halfsib oak families were also compared for allelic diversity,including group variations;genotypic structure;genetic diversity;and the degree of genetic subdivision and diff erentiation.The level of genetic variation and subdivision was lower in the hybrid families than in the families of the parental species.Genotypic analysis of the half-sibling off spring showed the asymmetric nature of interspecifi c hybridization processes of pedunculate and sessile oaks in mixed stands.展开更多
Molecular genetic maps were commonly constructed by analyzing the segregation of restriction fragment length polymorphisms (RFLPs). Here we described methodology-marker sequences in a new mapping based on recent docum...Molecular genetic maps were commonly constructed by analyzing the segregation of restriction fragment length polymorphisms (RFLPs). Here we described methodology-marker sequences in a new mapping based on recent documents. With the methods they were unique sequences detected by the polymerase chain reaction (PCR). Each of the methods had its Iimitations and the current trend was to integrate the maps produced by the different methods. Marker sequences contained mainly expressed sequence tags (ESTs),polymorphie sequence-tagged sites (STSs), randomly amplified polymorphic DNA (RAPDs), cIeaved amplified polymorphic sequences (CAPS), amplified fragment Iength pofymorphism (AFLPs), genorne sequence sampling (GSS) and sequence-tagged connectors (STCs) in this paper.展开更多
A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA (RAPD), amplified fragme...A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers in establishing genetic relationships among 29 almond cultivars and three related wild species. SSRs presented a high level of polymorphism and greater information content, as assessed by the expected hetrozygosity, compared to AFLPs and RAPDs. The lowest values of expected hetrozygosity were obtained for AFLPs; however AFLPs showed the highest efficiency, owing to their capacity to reveal large numbers of bands per reaction, which led to high values for various types of indices of diversity. All the three techniques discriminated almond genotypes very effectively, except that SSRs failed to discriminate between ‘Monagha’ and ‘Sefied’ almond genotypes. The correlation coefficients of similarity were statistically significant for all the three marker systems, but were lower for the SSR data than for RAPDs and AFLPs. For all the markers, high similarity in dendrogram topologies was obtained, although some differences were observed. All the dendrograms, including that obtained by the combined use of all the marker data, reflect relationships for most of cultivars according to their geographic diffusion. AMOVA detected more variation among cultivated and related wild species of almond within each geographic group. Bootstrap analysis revealed that the number of markers used was sufficient for reliable estimation of genetic similarity and for meaningful comparisons of marker types.展开更多
Random Amplified Polymorphic DNA （RAPD） polymor- phism was employed to assess the genetic diversity in the elite germplasm＇of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, origi...Random Amplified Polymorphic DNA （RAPD） polymor- phism was employed to assess the genetic diversity in the elite germplasm＇of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity （Ht） varied between 0.01 and 0.37, with an average of 0.19. Shannon＇s Information index （I） varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content （PIC）, Marker Index （MI） and Effective Multiplex Ratio （EMR） values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.展开更多
Organogenesis was induced in callus derived from mature zygotic embryos of six families (J-56, S-1003, E-22, E-311, E-440, and Mc) of loblolly pine (Pinus taeda L.) within 24 weeks of culture. Elongation of adventitio...Organogenesis was induced in callus derived from mature zygotic embryos of six families (J-56, S-1003, E-22, E-311, E-440, and Mc) of loblolly pine (Pinus taeda L.) within 24 weeks of culture. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg·L?1 indole-3-butyric acid (IBA) and 1 mg/l 6-benzyladenine (BA). The most suitable medium for root formation proved to be TE medium supplemented with 0.5 mg·L?1 IBA, 2mg·L?1 BA and 0.5 mg/l gibberellic acid (GA3). 169 regenerated plantlets were transferred to a perlite: peatmoss: vermiculite (1∶1∶1) soil mixture, and 98 plantlets survived in the field. Total DNA was extracted from the needles of the regenerated plantlets of the six families of loblolly pine. Analysis of random amplified polymorphic DNA (RAPD) using 20 arbitrary oligonucleotide 10-mers, show that amplification products were monomorphic for all the plantlets of family J-56, S-1003, E-22, E-311, E-440, and Mc of loblolly pine. These results suggested that organogenesis can be used for clonal micropropagation of some families of loblolly pine.展开更多
Objective To investigate the association between total homocysteine(tHcy)level in plasma and methylenetetrahydrofblate reductase(MTHFR)C677T and A1298C genetic polymorphisms in a Chinese Han nationality population wit...Objective To investigate the association between total homocysteine(tHcy)level in plasma and methylenetetrahydrofblate reductase(MTHFR)C677T and A1298C genetic polymorphisms in a Chinese Han nationality population with type 2 diabetes mellitus(T2DM)accompanied by dyslipidemia.Methods This case-control study enrolled T2DM patients with dyslipidemia and without dyslipidemia respectively.Sanger dideoxy-mediated chain-termination method was used to detect the gene polymorphisms of MTHFR C677T and A1298C.Plasma tHcy and lipid levels were measured as well.The genotype frequency and allele frequency between the dyslipidemia and non-dyslipidemia groups were compared by using Chi-square test.Plasma tHcy level ofT2DM patients who carried the different genotypes was compared by Student's t test.Results Finally,82 T2DM patients with dyslipidemia and 94 ones without dyslipidemia were included in this study.There was a significant correlation between tHcy level and MTHFR C677T gene polymorphism inT2DM patients(t=2.27,P=0.02).Moreover,the plasma tHcy level in the dyslipidemia patients who carried MTHFR 677TT genotype was significantly higher than that in those with CT+CC genotype(13.62+6.97 vs.10.95+3.62pmol/L,t=2.2O,P=0.03);while for patients without dyslipidemia,comparison of the tHcy level between those who carried the above two alleles showed no significantly difference(13.34±6.03 vs.12.04±5.09μmol/L,t=1.08,P=0.29).Conclusion MTHFR 677TT genotype might associate with higher tHcy level in T2DM patients with dyslipidemia.展开更多
Objective To examine the relationship between apolipoprotein E (Apo E) gene polymorphism and risk of coronary artery disease (CAD), analyzing association of polymorphism with classical risk factors. Methods A total of...Objective To examine the relationship between apolipoprotein E (Apo E) gene polymorphism and risk of coronary artery disease (CAD), analyzing association of polymorphism with classical risk factors. Methods A total of 124 patients (including 84 Han population and 40 Uygur population) with angiographically verified CAD or myocardial infarction were prospectively evaluated. Data referring to hypertension, diabetes, and tobacco consump-tion were recorded. The levels of total cholesterol (TC), high density lipoprotein (HDL) cholesterol, Apo A1 and B, and triglycerides (TG) were determined. DNA was obtained from 124 patients and 70 controls. In order to determine Apo E genotypes, DNA was PCR amplified and digested with HhaI. The genetic polymorphism of Apo E is due to three common alleles, epsilon(ε) 2, ε3, ε4, at a single autosomal gene locus. These alleles determine the six phenotypes E2/2, E3/3, E4/4, E4/2, E4/3, and E3/2. Results In Uygur population, the frequency of the ε2, ε3, and ε4 was 0.155, 0.648, and 0.197 respectively. In Han po-pulation, the frequency of the ε2, ε3, and ε4 was 0.081, 0.772, and 0.146 respectively. In the patient group, the frequency of the ε2, ε3, and ε4was 0.060, 0.758, and 0.182 respectively. In the control group, the frequency of the ε2, ε3, and ε4 was 0.193, 0.671, and 0.136 respectively. ε2 frequency of Uygur’ patients and controls was 0.050 and 0.290 respectively. Serum low density lipoprotein (LDL) cholesterol, TC, and TG values tended to decrease from the Apo E-4 phenotypes to Apo E-2 phenotypes. When deletion polymorphism of ε2 was compared with the common risk factors for CAD, its risk ratio (RR) is 4.38. Conclusions These studies confirm and find that Apo E phenotype distribution in Uygur population differs significantly from that in Han population in Xinjiang. CAD patients have significantly lower ε2 allele and slightly higher ε3 or ε4 allele frequency than controls, especially in Uygur population. It shows protective effects of ε2 on CAD.展开更多
Objective To analyze the relationship between tumor necrosis factor-alpha (TNFα) gene promoter -308 polymorphism and myasthenia gravis (MG) in Chinese and analyze secretion of TNFα in peripheral blood mononuclear ce...Objective To analyze the relationship between tumor necrosis factor-alpha (TNFα) gene promoter -308 polymorphism and myasthenia gravis (MG) in Chinese and analyze secretion of TNFα in peripheral blood mononuclear cells (PBMC) in MG patients. Methods A biallelic polymorphism at position -308 in the promoter of TNFα gene was screened by PCR amplification and NcoI recognition site. One hundred and twenty-three MG cases and 115 healthy controls were included in this study. MG patients were classified to different groups according to clinical type, age at onset, and sex respectively. PBMC were isolated from 20 patients and 20 healthy controls, and then cultured in the presence or absence of phytohemag- glutinin (PHA) and acetycholine receptors (AchR). The supernatants were harvested after incubation and stored until TNFα was assayed by enzyme-linked immunosorbent assay. Results The frequency of TNFα-308 allele 2 (A) was found significantly increase in MG patients and showed a trend especially in late onset (≥ 40 years) and male patients (P < 0.05). The allele A had no relationship with thymic pathogenesis in MG patients. But frequency of allele A was significantly higher in general type than in ocular type (P < 0.05). MG patients had a higher inducible level of TNFα by PHA and AchR, and could be down regulated after treatment. Conclusion Polymorphism in TNFα gene promoter -308 is associated with onset of MG. The microsatellite allele TNFα2 confer risk for the development of MG in Chinese patients. MG patients have a higher inducible level of TNFα.展开更多
The klotho gene has been identified as an aging suppressor that encodes a protein involved in cardiovascular disease （CVD）. The inac- tivation of the klotho gene causes serious systemic disorders resembling human ag...The klotho gene has been identified as an aging suppressor that encodes a protein involved in cardiovascular disease （CVD）. The inac- tivation of the klotho gene causes serious systemic disorders resembling human aging, such as atherosderosis, diffuse vascular calcification and shortened life span. Klotho has been demonstrated to ameliorate vascular endothelial dysfunction and delay vascular calcification. Fur- thermore, klotho gene polymorphisms in the human are associated with various cardiovascular events. Recent experiments show that klotho may reduce transient receptor potential canonical6 （TRPC6） channels, resulting in protecting the heart from hypertrophy and systolic dys- function. Fibroblast growth factor23 （FGF23） is a bone-derived hormone that plays an important role in the regulation of phosphate and vi- tamin D metabolism. FGF23 accelerates urinary phosphate excretion and suppresses 1,25-dihydroxy vitaminD3 （1,25（OH）2D3）synthesis in the presence ofFGF receptorl （FGFR1） and its co-receptor ldotho, principally in the kidney. The hormonal affects of circulating klotho pro- tein and FGF23 on vascular and heart have contributed to an understanding of their roles in the pathophysiology of arterial stiffness and left ventricular hypertrophy. Klotho and FGF23 appear to play a critical role in the pathogenesis of vascular disease, and may represent a novel potential therapeutic strategy for clinical intervention.展开更多
Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at...Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.展开更多
文摘The genetic diversity of the populations for 14 wild green peafowls (Pavo muticus) and 18 captive green pea-fowls was investigated by using the technology of random amplified polymorphic DNA (RAPD). Totally 161 and 166 ampli-fied bands were obtained by using 23 arbitrary primers to amplify the genomic DNA of wild and captive green peafowls re-spectively. The results showed that the average relative genetic distance of the wild and captive green peafowls popula-tions was 0.0555 and 0.1355, respectively, and difference of the average relative genetic distances between the two popu-lations was 0.1635. The Shannon diversity index for the wild and captive green peafowl populations was 0.4348 and 1.0163, respectively, which means that there exists significant difference in genetic diversity between the two populations, and the genetic diversity of wild green peafowl was low. The two populations originated from two different families according to analysis by the UPGMA method. This research can provide the theoretical basis for supervising genealogies management of peafowl populations.
基金supported in part by the Cernet Network (NGII20160103)National Natural Science Foundation of China, National Natural Science Foundation of China(No.61672471)+3 种基金Fundamental Research Funds for the He’nan Province University (No.17KYYWF0202)He’nan Province University science and technology innovation team(No.18IRTSTHN012)Plan For Scientific Innovation Talent of Henan Province (No.184200510010)Zhengzhou University of Light Industry Doctoral Fund (2016BSJJ041) funding
文摘The current Internet has evolved during the last decade to a global provider of diverse applications. However, the underlying structure of routing and addressing has not evolved in the same pace and is somewhat inflexible. How to provide diverse routing services, support emerging communication paradigms based on limited and definite network resources has become an urgent challenge. This paper investigates the adaptive matching between routing and application through network function decomposition and composition, and proposes a polymorphic routing model to support diverse applications and emerging communication paradigms. The model splits complex routing functions into its constituents, and derives customized routing mechanisms supporting various applications by composing the routing constituents. The derivation process is modeled as a Markov Decision Process (MDP), and a polymorphic derivation algorithm is also proposed to derive customized routing instances for diverse applications. The model enables the network to self-adjust routing services dynamically to adapt to the different requirements of applications, supports coexistence of multiple routing modes and communication paradigms, and provides a feasible solution for the network compatibility and evolvement. We describe the key design and demonstrate the feasibility of polymorphic derivation by simulations. We also present case studies that demonstrate key functionalities the polymorphic routing model enables.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11304294 and 11274281)the Science Fund from the National Laboratory of Shock Wave and Detonation Physics of China(Grant Nos.9140C670201140C67281 and 9140C670102150C67288)
文摘The high-pressure polymorphs and structural transformation of Sn were experimentally investigated using angle- dispersive synchrotron x-ray diffraction up to 108.9 GPa. The results show that at least at 12.8 GPa β-Sn→bct structure transformation was completed and no two-phase coexistence was found. By using a long-wavelength x-ray, we resolved the diffraction peaks splitting and discovered the formation of a new distorted orthorhombic structure bco from the bct structure at 31.8 GPa. The variation of the lattice parameters and their ratios with pressure further validate the observation of the bco polymorph. The bcc structure appears at 40.9 GPa and coexists with the bco phase throughout a wide pressure range of 40.9 GPa-73.1 GPa. Above 73.1 GPa, only the bcc polymorph is observed, The systematically experimental investigation confirms the phase transition sequence of Sn asβ-Sn→bct→bco→bco ＋ bcc→bcc upon compression to 108.9 GPa at room temperature.
基金supported by the Ministry of Science and Higher Education of the Russian Federation(Agreement with Zelinsky Institute of Organic Chemistry RAS Grant No.075-15-2020-803).
文摘In this work, comprehensive studies of 2,4-dinitroanisole(2,4DNAN) were carried out using powder thermorentgenography of the internal standard. The time of the complete polymorphic transition in the solid phase β→a in 2,4DNAN under various combinations of conditions has been determined. It has been established that, regardless of the season of manufacture of the substance, when it is stored for 8-9months, with a change in ambient temperature from minus 30℃ to plus 30℃, a complete polymorphic transition β→a occurs. When stored in conditions below minus 5℃, polymorphic transition does not occur. When stored in conditions above plus 30℃ in a closed container, polymorphic transition occurs within 3 weeks. The polymorphic transition is accompanied by a decrease in density by 1.3%-1.5% and an increase in melting temperature by 10-12℃, depending on the degree of purity of the starting substance. The activation energy of the molecular rearrangement was 68-70 k J/mol(16.5 ± 3 kcal/mol). The mechanism of polymorphic transition has been evaluated, which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the product. The average activation energy of the polymorphic transition process was 110 ± 6.2 k J/mol(26.2 kcal/mol). In an open container, reactions proceed by a homogeneous mechanism, and in a closed container by a heterogeneous mechanism involving the gas phase.
文摘To investigate the levels of polymorphisms and Mendelian segregation ratio in clone “TB01” (P. tomentosa×P. bolleana) ×clone “LM50” (P. tomentosa) BC 1 population at the entire genome level, amplified fragment length polymorphisms (AFLPs) analysis was conducted for both parents and 120 progenies. Forty one pairs of selective primers were used to detect 2?707 bands, of which 712 (26.4%) were polymorphic. Chi\|square tests were performed to examine if the observed genotypic frequencies of AFLP loci deviated from expected 1∶1 Mendelian segregation ratio ( P <0.01) in BC 1 population. Among the 712 loci 571 (80.2%) fit to Mendelian 1∶1 segregation ratio, corresponding to DNA polymorphisms heterozygous in one parent and a null in the other. The result shows that the AFLP markers are very suitable for fingerprinting and genetic mapping in the Chinese white poplar (Populus tomentosa Carr.).
基金supported by the National 863 Program (2002BA515B0401)National Natural Science Foundation of China (30571513)Foundation of Heilongjiang Province (GA06B301)
文摘The fiber length trait （FLT） of 538 individuals from nature birch population in Maorshan region, Heilongjang, China were measured, of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA （RAPD） technique. In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors, and a correlative segment BFLR-16 was obtained. The correlation coefficient between BFLI-16 and FLT was 0.6144, with the significant level of 1%. BFLI-16 was then cloned, sequenced and transformed into SCAR marker. The percentage of identifying long fiber birches by this SCAR was more than 92. The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length, and its existence is significantly correlative with the increase in the fiber length.
文摘Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions （SCAR） marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex （MHC） class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference （p〈0.01） in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.
基金supported by a research project(No.Z111021402)of Northwest A&F Universitythe Ministry of Natural Resources and Environment,Vietnam government,Hanoiand IDEA WILD equipment to Vu Dinh Duy,Bui Thi Tuyet Xuan
文摘Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for T.wallichiana, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.
基金partly supported by the long-term research programme Sustainable Forestry and Global Changes implemented by the Lithuanian Research Centre for Agriculture and Forestry
文摘This study was conducted to determine the parent-off spring genetic structure of the pedunculate oak(Quercus robur L.),sessile oak(Q.petraea[Matt.]Liebl.)and their hybrids.Forty half-sib Quercus families and their maternal trees originating from one tree stand in southern Lithuania were analyzed using SSR and RAPD markers.Based on a preliminary study of leaf morphological traits,the individuals separated into six groups.The studied halfsib oak families were also compared for allelic diversity,including group variations;genotypic structure;genetic diversity;and the degree of genetic subdivision and diff erentiation.The level of genetic variation and subdivision was lower in the hybrid families than in the families of the parental species.Genotypic analysis of the half-sibling off spring showed the asymmetric nature of interspecifi c hybridization processes of pedunculate and sessile oaks in mixed stands.
文摘Molecular genetic maps were commonly constructed by analyzing the segregation of restriction fragment length polymorphisms (RFLPs). Here we described methodology-marker sequences in a new mapping based on recent documents. With the methods they were unique sequences detected by the polymerase chain reaction (PCR). Each of the methods had its Iimitations and the current trend was to integrate the maps produced by the different methods. Marker sequences contained mainly expressed sequence tags (ESTs),polymorphie sequence-tagged sites (STSs), randomly amplified polymorphic DNA (RAPDs), cIeaved amplified polymorphic sequences (CAPS), amplified fragment Iength pofymorphism (AFLPs), genorne sequence sampling (GSS) and sequence-tagged connectors (STCs) in this paper.
文摘A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers in establishing genetic relationships among 29 almond cultivars and three related wild species. SSRs presented a high level of polymorphism and greater information content, as assessed by the expected hetrozygosity, compared to AFLPs and RAPDs. The lowest values of expected hetrozygosity were obtained for AFLPs; however AFLPs showed the highest efficiency, owing to their capacity to reveal large numbers of bands per reaction, which led to high values for various types of indices of diversity. All the three techniques discriminated almond genotypes very effectively, except that SSRs failed to discriminate between ‘Monagha’ and ‘Sefied’ almond genotypes. The correlation coefficients of similarity were statistically significant for all the three marker systems, but were lower for the SSR data than for RAPDs and AFLPs. For all the markers, high similarity in dendrogram topologies was obtained, although some differences were observed. All the dendrograms, including that obtained by the combined use of all the marker data, reflect relationships for most of cultivars according to their geographic diffusion. AMOVA detected more variation among cultivated and related wild species of almond within each geographic group. Bootstrap analysis revealed that the number of markers used was sufficient for reliable estimation of genetic similarity and for meaningful comparisons of marker types.
文摘Random Amplified Polymorphic DNA （RAPD） polymor- phism was employed to assess the genetic diversity in the elite germplasm＇of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated frorri six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity （Ht） varied between 0.01 and 0.37, with an average of 0.19. Shannon＇s Information index （I） varied between 0102 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content （PIC）, Marker Index （MI） and Effective Multiplex Ratio （EMR） values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.
文摘Organogenesis was induced in callus derived from mature zygotic embryos of six families (J-56, S-1003, E-22, E-311, E-440, and Mc) of loblolly pine (Pinus taeda L.) within 24 weeks of culture. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg·L?1 indole-3-butyric acid (IBA) and 1 mg/l 6-benzyladenine (BA). The most suitable medium for root formation proved to be TE medium supplemented with 0.5 mg·L?1 IBA, 2mg·L?1 BA and 0.5 mg/l gibberellic acid (GA3). 169 regenerated plantlets were transferred to a perlite: peatmoss: vermiculite (1∶1∶1) soil mixture, and 98 plantlets survived in the field. Total DNA was extracted from the needles of the regenerated plantlets of the six families of loblolly pine. Analysis of random amplified polymorphic DNA (RAPD) using 20 arbitrary oligonucleotide 10-mers, show that amplification products were monomorphic for all the plantlets of family J-56, S-1003, E-22, E-311, E-440, and Mc of loblolly pine. These results suggested that organogenesis can be used for clonal micropropagation of some families of loblolly pine.
基金the National Key Development Plan for Precision Medicine Research(2017YFC0910004)Jinan Science Project(201602171),and Jinan Science and Technology Plan Project(201503009).
文摘Objective To investigate the association between total homocysteine(tHcy)level in plasma and methylenetetrahydrofblate reductase(MTHFR)C677T and A1298C genetic polymorphisms in a Chinese Han nationality population with type 2 diabetes mellitus(T2DM)accompanied by dyslipidemia.Methods This case-control study enrolled T2DM patients with dyslipidemia and without dyslipidemia respectively.Sanger dideoxy-mediated chain-termination method was used to detect the gene polymorphisms of MTHFR C677T and A1298C.Plasma tHcy and lipid levels were measured as well.The genotype frequency and allele frequency between the dyslipidemia and non-dyslipidemia groups were compared by using Chi-square test.Plasma tHcy level ofT2DM patients who carried the different genotypes was compared by Student's t test.Results Finally,82 T2DM patients with dyslipidemia and 94 ones without dyslipidemia were included in this study.There was a significant correlation between tHcy level and MTHFR C677T gene polymorphism inT2DM patients(t=2.27,P=0.02).Moreover,the plasma tHcy level in the dyslipidemia patients who carried MTHFR 677TT genotype was significantly higher than that in those with CT+CC genotype(13.62+6.97 vs.10.95+3.62pmol/L,t=2.2O,P=0.03);while for patients without dyslipidemia,comparison of the tHcy level between those who carried the above two alleles showed no significantly difference(13.34±6.03 vs.12.04±5.09μmol/L,t=1.08,P=0.29).Conclusion MTHFR 677TT genotype might associate with higher tHcy level in T2DM patients with dyslipidemia.
文摘Objective To examine the relationship between apolipoprotein E (Apo E) gene polymorphism and risk of coronary artery disease (CAD), analyzing association of polymorphism with classical risk factors. Methods A total of 124 patients (including 84 Han population and 40 Uygur population) with angiographically verified CAD or myocardial infarction were prospectively evaluated. Data referring to hypertension, diabetes, and tobacco consump-tion were recorded. The levels of total cholesterol (TC), high density lipoprotein (HDL) cholesterol, Apo A1 and B, and triglycerides (TG) were determined. DNA was obtained from 124 patients and 70 controls. In order to determine Apo E genotypes, DNA was PCR amplified and digested with HhaI. The genetic polymorphism of Apo E is due to three common alleles, epsilon(ε) 2, ε3, ε4, at a single autosomal gene locus. These alleles determine the six phenotypes E2/2, E3/3, E4/4, E4/2, E4/3, and E3/2. Results In Uygur population, the frequency of the ε2, ε3, and ε4 was 0.155, 0.648, and 0.197 respectively. In Han po-pulation, the frequency of the ε2, ε3, and ε4 was 0.081, 0.772, and 0.146 respectively. In the patient group, the frequency of the ε2, ε3, and ε4was 0.060, 0.758, and 0.182 respectively. In the control group, the frequency of the ε2, ε3, and ε4 was 0.193, 0.671, and 0.136 respectively. ε2 frequency of Uygur’ patients and controls was 0.050 and 0.290 respectively. Serum low density lipoprotein (LDL) cholesterol, TC, and TG values tended to decrease from the Apo E-4 phenotypes to Apo E-2 phenotypes. When deletion polymorphism of ε2 was compared with the common risk factors for CAD, its risk ratio (RR) is 4.38. Conclusions These studies confirm and find that Apo E phenotype distribution in Uygur population differs significantly from that in Han population in Xinjiang. CAD patients have significantly lower ε2 allele and slightly higher ε3 or ε4 allele frequency than controls, especially in Uygur population. It shows protective effects of ε2 on CAD.
文摘Objective To analyze the relationship between tumor necrosis factor-alpha (TNFα) gene promoter -308 polymorphism and myasthenia gravis (MG) in Chinese and analyze secretion of TNFα in peripheral blood mononuclear cells (PBMC) in MG patients. Methods A biallelic polymorphism at position -308 in the promoter of TNFα gene was screened by PCR amplification and NcoI recognition site. One hundred and twenty-three MG cases and 115 healthy controls were included in this study. MG patients were classified to different groups according to clinical type, age at onset, and sex respectively. PBMC were isolated from 20 patients and 20 healthy controls, and then cultured in the presence or absence of phytohemag- glutinin (PHA) and acetycholine receptors (AchR). The supernatants were harvested after incubation and stored until TNFα was assayed by enzyme-linked immunosorbent assay. Results The frequency of TNFα-308 allele 2 (A) was found significantly increase in MG patients and showed a trend especially in late onset (≥ 40 years) and male patients (P < 0.05). The allele A had no relationship with thymic pathogenesis in MG patients. But frequency of allele A was significantly higher in general type than in ocular type (P < 0.05). MG patients had a higher inducible level of TNFα by PHA and AchR, and could be down regulated after treatment. Conclusion Polymorphism in TNFα gene promoter -308 is associated with onset of MG. The microsatellite allele TNFα2 confer risk for the development of MG in Chinese patients. MG patients have a higher inducible level of TNFα.
文摘The klotho gene has been identified as an aging suppressor that encodes a protein involved in cardiovascular disease （CVD）. The inac- tivation of the klotho gene causes serious systemic disorders resembling human aging, such as atherosderosis, diffuse vascular calcification and shortened life span. Klotho has been demonstrated to ameliorate vascular endothelial dysfunction and delay vascular calcification. Fur- thermore, klotho gene polymorphisms in the human are associated with various cardiovascular events. Recent experiments show that klotho may reduce transient receptor potential canonical6 （TRPC6） channels, resulting in protecting the heart from hypertrophy and systolic dys- function. Fibroblast growth factor23 （FGF23） is a bone-derived hormone that plays an important role in the regulation of phosphate and vi- tamin D metabolism. FGF23 accelerates urinary phosphate excretion and suppresses 1,25-dihydroxy vitaminD3 （1,25（OH）2D3）synthesis in the presence ofFGF receptorl （FGFR1） and its co-receptor ldotho, principally in the kidney. The hormonal affects of circulating klotho pro- tein and FGF23 on vascular and heart have contributed to an understanding of their roles in the pathophysiology of arterial stiffness and left ventricular hypertrophy. Klotho and FGF23 appear to play a critical role in the pathogenesis of vascular disease, and may represent a novel potential therapeutic strategy for clinical intervention.
基金Supported by National Natural Science Foundation of China (30393130, 30470651)National Basic Research Program of China (973 Program) (2006BAI19B07, 2006CB504103)National Key Laboratory Specific Fund (2060204)
文摘Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.
