Understanding the formation of lithium-rich pegmatites is critical for meeting global lithium demand.The 509 Daobanxi Li pegmatite deposit,located in the West Kunlun orogenic belt of northwestern China,represents a si...Understanding the formation of lithium-rich pegmatites is critical for meeting global lithium demand.The 509 Daobanxi Li pegmatite deposit,located in the West Kunlun orogenic belt of northwestern China,represents a significant example of an LCT-type(Li-Cs-Ta)pegmatite system.This study investigates the paragenetic sequence of lithium(Li)minerals and the factors controlling their crystallization,providing new insights into the magmatic-hydrothermal evolution of rare-element pegmatites.Pegmatite dikes exhibit distinct zonation,comprising a wall rock zone,a border zone(aplitic layer),and a core zone(pegmatitic layer),with Li mineralization concentrated in the pegmatitic and aplitic layers.The primary Li minerals include spodumene(Spd),montebrasite(Mbs),eucryptite(Ecr),elbaite(Elb),and lepidolite(Lpd),which crystallize in the order of spodumene→montebrasite→elbaite→lepidolite.Spodumene,the dominant Li-bearing mineral,crystallizes from a Li-saturated melt during the magmatic stage.Montebrasite,a Li-phosphate mineral,forms in P-rich environments,coexisting with spodumene and columbite-group minerals(CGM).During the magmatic-hydrothermal transition,elbaite crystallizes from a B-rich melt,exhibiting skeletal and patchy zoning due to undercooling and disequilibrium crystallization.Hydrothermal alteration leads to the breakdown of spodumene and the formation of secondary minerals such as eucryptite and lepidolite,with lepidolite being the final Li-bearing phase,enriched in fluorine.The coupled dissolution-precipitation processes during the magmatic-hydrothermal transition play a critical role in the remobilization and enrichment of rare elements such as Li,Nb,Ta,and Sn.This deposit,characterized by spodumene crystallization in the Spd+Quartz stability field(≥300 MPa,≤725℃)and subsequent alteration to Ecr+quartz assemblages(<270℃,<160 MPa),exhibits broader temperature-pressure conditions exceeding typical global pegmatites like Tanco,with no petalite formation observed due to its persistent exclusion from petalite stability fields throughout mineralization.The shear zone controls the pegmatite emplacement and lithium enrichment in the 509 Daobanxi lithium deposit,and its deformation-fluid coupling mechanism provides new insights for the exploration of LCT pegmatite deposits.The present study highlights the importance of understanding both magmatic and hydrothermal processes in the formation of LCT-type pegmatites and provides valuable insights for the exploration of critical metal resources in similar geological settings.展开更多
The precipitation sequence of η（MgZn2） phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy was investigated by examining samples aged at 135 ℃ for various times from 5 min to 6 h. High resolution transmiss...The precipitation sequence of η（MgZn2） phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy was investigated by examining samples aged at 135 ℃ for various times from 5 min to 6 h. High resolution transmission electron microscopy （HRTEM） observations and energy dispersive X-ray spectroscopy （EDX） analysis indicate that the precipitation sequence of η phase along low-angle grain boundaries should be supersaturated solid solution （SSS）→vacancy-rich clusters （VRC）→GP Ⅱ zones→η＇→η. Based on the theory of non-equilibrium grain boundary segregation （NGS） and non-equilibrium grain boundary co-segregation （NGCS）, the excessive solute elements gradually segregate to the grain boundaries by the diffusion of the solute-vacancy complex during aging treatment. The grain boundary segregation plays an important role in the nucleation and growth of VRC, GP Ⅱ zones, η＇ phase as well as η phase.展开更多
[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. ...[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck.展开更多
Pathogenic Escherichia coli cause chicken colibacillosis, which is economically devastating to the poultry in- dustry worldwide （Bagheri et al., 2014）. Owing to in- creasing antibiotic resistance, phage therapy reag...Pathogenic Escherichia coli cause chicken colibacillosis, which is economically devastating to the poultry in- dustry worldwide （Bagheri et al., 2014）. Owing to in- creasing antibiotic resistance, phage therapy reagents have been developed to treat bacterial infections （Xu et al., 2015）.展开更多
Enterococci bacteria are important in environmental, food and clinical microbiology. Enterococcus faecium is a nosocomial pathogen that causes bacteremia, endocarditis and other infections. It is among the most preval...Enterococci bacteria are important in environmental, food and clinical microbiology. Enterococcus faecium is a nosocomial pathogen that causes bacteremia, endocarditis and other infections. It is among the most prevalent organisms encountered in hospital-associated infections accounting for approximately 12% of nosocomial infections in the USA （Linden and Miller, 1999）. However, certain strains of E. faecium are not only non-pathogenic but also have beneficial effects on human health with probiotic potential. For example, E. faecium T-110 is a consortium member in several probiotic products including BIO-THREE~ which is widely prescribed for human, animal and aqua-cultural use. This strain was originally developed by TOA Pharmaceuticals in Japan, and later used in the probiotic products of several other companies.展开更多
Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. Ho...Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. However, the outcome of.this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen. The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter （DM）, crude protein （CP）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal. Four multiparous Holstein lactating cows fitted with permanent ruminal cannulas were used. The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals （all in-gradually out method; AG） or were placed in the rumen at designated time points and retrieved at once （gradually in-all out method; GA）. Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability （ED） of DM and CP were significantly higher in the AG compared to the GA method （P〈0.05）. Fractional rates of DM and CP degradation was higher in alfalfa haylage samples incubated in the rumen using the AG method compared to that using the GA method （0.138 h-1 vs. 0.073 h-1 and 0.002 h-1 vs. 0.1125 h-1, for DM and CP, respectively; P〈0.05）. Due to a higher fractional rate of degradation （Kd） of DM and CP, the ED of DM and CP at different fractional passage rates were higher in the AG than those in the GA method （P〈0.05）. Potentially degradable fraction and lag time of NDF were higher in the AG method compared to the GA method （P〈0.05）. Placing all bags in the rumen at once and removing them at designated time intervals compared with introduction of bags in reverse sequence and removing them all at once led to a lower undegradable fraction （U） of NDF in alfalfa （1.8% vs. 4.0%, respectively; P〈0.05） and corn silage （3.3% vs. 6.7%, respectively; P〈0.05） samples. Potentially degradable fraction of ADF was significantly higher in the AG method compared with the GA method （P〈0.05）. Bag incubation sequence had profound effects on kinetics of degradation of DM, CP and NDF in situ in the feed samples studied. The effects were more evident in the forages （especially alfalfa haylage） than in the concentrate ingredientsnamely corn grain and soybean meal..This experiment is the first time to investigate effects of two methods under the same experiment conditions, providing basic data for the determination of ED.展开更多
In this paper, an infinite sequence of conservation laws for a generalized variable-coefficient fifth-order Korteweg-de Vries equation in fluids are constructed based on the Backlund transformation. Hirota bilinear fo...In this paper, an infinite sequence of conservation laws for a generalized variable-coefficient fifth-order Korteweg-de Vries equation in fluids are constructed based on the Backlund transformation. Hirota bilinear form and symbolic computation are applied to obtain three kinds of solutions. Variable coefficients can affect the conserved density, associated flux, and appearance of the characteristic lines. Effects of the wave number on the soliton structures are also discussed and types of soliton structures, e.g., the double-periodic soliton, parallel soliton and soliton complexes, are presented.展开更多
The topological pressure for subadditive sequence of discontinuous functions is defined on any invariant subset having a nested family of subsets in the compact metric space. Two subadditive variational principles ass...The topological pressure for subadditive sequence of discontinuous functions is defined on any invariant subset having a nested family of subsets in the compact metric space. Two subadditive variational principles associated with two different relatively weak conditions are developed for the defined topological pressure. As an application, we give an example on systems with nonzero Lyapunov exponents.展开更多
Water is a major limiting factor for food production and many countries fail to produce sufficient food for their population due to severe water scarcity （Jury and Vaux, 2005）. Rice is the main staple food worldwide...Water is a major limiting factor for food production and many countries fail to produce sufficient food for their population due to severe water scarcity （Jury and Vaux, 2005）. Rice is the main staple food worldwide. More than 50% of rice in the world is rain-fed and drought causes severe reduction in rice grain yield in rain-fed environments （Venuprasad et al., 2007; Zhang, 2007; Sandhu et al., 2014）. Therefore, enhancing drought resistance （DR） of rice is important for food security. However, DR is a complex trait, which is controlled by a large number of loci with small effect and is also affected by different genetic background, genotype-by-environment interaction and other stresses such as heat （Hu and Xiong, 2014）.展开更多
The paper aims to reconstruct the eruption sequence of the permanent teeth of Lufengpithecus lufengensis. Eruption sequence here means the order of appearance of the tooth crowns out of the alveolar crypt. The permane...The paper aims to reconstruct the eruption sequence of the permanent teeth of Lufengpithecus lufengensis. Eruption sequence here means the order of appearance of the tooth crowns out of the alveolar crypt. The permanent dental developments of five juvenile mandibles are observed and analyzed via radiograph. Using such records as the stages of crown and root formation, location of the crown occlusion relative to the alveolar margin, and wear degrees of the erupted teeth, the eruption sequence of the mandibular permanent teeth of Lufengpithecus lufengensis is reasonably derived as M1 I1 I2 M2 P3 P4 C M3. This order is seen to differ very markedly from that in modern humans, and to be similar to that in apes.展开更多
The idea of difference sequence spaces was introduced in （Klzmaz, 1981） and this concept was generalized in （Et and Colak, 1995）. In this paper we define some difference sequence spaces by a sequence of Orlicz fun...The idea of difference sequence spaces was introduced in （Klzmaz, 1981） and this concept was generalized in （Et and Colak, 1995）. In this paper we define some difference sequence spaces by a sequence of Orlicz functions and establish some inclusion relations.展开更多
The idea of difference sequence sets X（△） = {x = （xk） ： △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence sp...The idea of difference sequence sets X（△） = {x = （xk） ： △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence spaces and give some inclusion relations.展开更多
A mechanism for proving global convergence in filter-SQP （sequence of quadratic programming） method with the nonlinear complementarity problem （NCP） function is described for constrained nonlinear optimization pro...A mechanism for proving global convergence in filter-SQP （sequence of quadratic programming） method with the nonlinear complementarity problem （NCP） function is described for constrained nonlinear optimization problem.We introduce an NCP function into the filter and construct a new SQP-filter algorithm.Such methods are characterized by their use of the dominance concept of multi-objective optimization,instead of a penalty parameter whose adjustment can be problematic.We prove that the algorithm has global convergence and superlinear convergence rates under some mild conditions.展开更多
In this paper, the complete convergence of weighted sums for ρ＊-mixing sequence of random variables is investigated. By applying moment inequality and truncation methods, the equivalent conditions of complete conver...In this paper, the complete convergence of weighted sums for ρ＊-mixing sequence of random variables is investigated. By applying moment inequality and truncation methods, the equivalent conditions of complete convergence of weighted sums for ρ＊-mixing sequence of random variables are established. We not only promote and improve the results of Li et al. （J. Theoret. Probab., 1995, 8（1）： 49--76） from i.i.d. to ρ＊-mixing setting but also obtain their necessities and relax their conditions.展开更多
Compared to the conventional two-tower suspension bridge, the three-tower suspension bridge has obviously different characteristics in structural performance because of the extra middle tower and main span. The constr...Compared to the conventional two-tower suspension bridge, the three-tower suspension bridge has obviously different characteristics in structural performance because of the extra middle tower and main span. The construction sequence for the stiffening girder is significantly different between the three-tower suspension bridge and the two-tower suspension bridge. The tangential angle of the main cable is one of the controlling factors of the stiffening girder erection stage for a suspension bridge. According to 5 feasible cases for the stiffening girder erection scheme in Taizhou Bridge, the research about the tangential angle in each case mentioned above was made, and some factors that should be taken into account for the erection scheme of stiffening girder were pointed out.展开更多
The Agrobacterium mediated transgenic rice ( Oryza saliva L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T-DNA were analyzed with inverse PC...The Agrobacterium mediated transgenic rice ( Oryza saliva L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T-DNA were analyzed with inverse PCR. Results showed that 65.4% of the T-DNA was integrated in different locations of rice genome, and some T-DNA flanking sequences were located on certain chromosomes. A number of T-DNA was found to have inserted into protein coding regions. In order to induce transposition of the inserted Ds elements, 354 crosses of Ac x Ds and Ds x Ac were constructed. The excision frequency of Ds element trans-activated by Ac transposase was 22.7% in the F-2 populations, and the transposition was confirmed with analyses of DNA sequences flanking the Ds elements. In addition to the transposition due to 'cut-paste' mechanism, Ds can replicate itself and integrate into a new locus, and inaccurate excisions were also found. A proportion of DNA segments flanking the Ds elements showed no homologies to sequences published in GenBank, of which two were registered under the accession numbers AF355153 and AF355770. The strategy of using transposon tagging for rice genomics study was discussed.展开更多
Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of ...Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of consecutive outcomes is generated. This can be seen as a game where m players select one such pattern each and the one whose pattern occurs first wins. We present symbolic formulas for the m probabilities of winning, and for the mean number of trials and the corresponding standard deviation to complete this game. Several numerical examples are presented, including a search for optimal strategy.展开更多
Follow Chen and Duda's model of spectral fall-off of ω~3, the dependence of peak parameters of ground motion, peak displacement d_m, peak velocity vin and peak acceleration a_m, upon the environment stress τ_o-v...Follow Chen and Duda's model of spectral fall-off of ω~3, the dependence of peak parameters of ground motion, peak displacement d_m, peak velocity vin and peak acceleration a_m, upon the environment stress τ_o-values are studied using near source seismic digital recordings for the sequence of the Wuding, Yunnan, M = 6.5 earthquake, in which, as a new thought, the peak parameters are assumed to be related to the medium Q-value. Three formulae for estimating the environment stress τ_o-values by the peak parameters of three types of ground motions are derived. Using these formulae, the environment stress τ_o-values are calculated for the sequence of the Wuding earthquake. The result show that τ_o-values calculated by the three formulae are constant largely, the averages of τ_o are in the range of 5.0-35 MPa for most earthquakes. It belongs to the high-stress earthquakes sequence: the high-stress values are restricted to the relatively small area closely near to the epicenter of the main shock. The fine distribu tion structure for the contours of the environment stress τ_o-values is related closely to the strong aftershocks. The analysis of spatial and temporal feature of To-values suggests that the earthquakes sequence in a rupture process generated at the specific intersection zone of seismo-tectonics under high-stress background.展开更多
Following China's announcement of its completion of the draft genome sequence of the rice indica subspecies on October 12,2001 (page 126, Bulletin of the Chinese Academy of Sciences Vol. 15 No.3), Chinese scie... Following China's announcement of its completion of the draft genome sequence of the rice indica subspecies on October 12,2001 (page 126, Bulletin of the Chinese Academy of Sciences Vol. 15 No.3), Chinese scientists published their findings in the April 5 issue of Science, the journal of the American Association for the Advancement of Science (AAAS). In the same issue, a team of scientists with the Switzerland-based Syngenta company reported a similar achievement for another major rice subspecies,japonica.……展开更多
The 3.0 kb BglⅡ+XbaⅠrestriction fragment of millet(Setaria italica) chloroplast genome containing rbcL gene had been cloned into pBluescript SK (-) vector, then the restriction map and the 1990 bp complete nucleotid...The 3.0 kb BglⅡ+XbaⅠrestriction fragment of millet(Setaria italica) chloroplast genome containing rbcL gene had been cloned into pBluescript SK (-) vector, then the restriction map and the 1990 bp complete nucleotide sequence was determined. The 1431 bp coding region of the gene consists of 476 amino acid residues with a predicted molecular weight of 52679 D. The 389 bp 5′ upstream region has the putative -10 box, -35 box and SD sequence, similar to that of procaryotes. The 170 bp 3′ downstream region contains three stem loop structures. Comparison of the rbcL gene sequences between C 4 plants and several C 3 plants reveals no difference in the coding region, promoter and 3′ downstream region. It might be concluded that the rbcL gene sequence has no relation with its cell specific expression.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42250202,92162323,42272075)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(No.24lgqb01).
文摘Understanding the formation of lithium-rich pegmatites is critical for meeting global lithium demand.The 509 Daobanxi Li pegmatite deposit,located in the West Kunlun orogenic belt of northwestern China,represents a significant example of an LCT-type(Li-Cs-Ta)pegmatite system.This study investigates the paragenetic sequence of lithium(Li)minerals and the factors controlling their crystallization,providing new insights into the magmatic-hydrothermal evolution of rare-element pegmatites.Pegmatite dikes exhibit distinct zonation,comprising a wall rock zone,a border zone(aplitic layer),and a core zone(pegmatitic layer),with Li mineralization concentrated in the pegmatitic and aplitic layers.The primary Li minerals include spodumene(Spd),montebrasite(Mbs),eucryptite(Ecr),elbaite(Elb),and lepidolite(Lpd),which crystallize in the order of spodumene→montebrasite→elbaite→lepidolite.Spodumene,the dominant Li-bearing mineral,crystallizes from a Li-saturated melt during the magmatic stage.Montebrasite,a Li-phosphate mineral,forms in P-rich environments,coexisting with spodumene and columbite-group minerals(CGM).During the magmatic-hydrothermal transition,elbaite crystallizes from a B-rich melt,exhibiting skeletal and patchy zoning due to undercooling and disequilibrium crystallization.Hydrothermal alteration leads to the breakdown of spodumene and the formation of secondary minerals such as eucryptite and lepidolite,with lepidolite being the final Li-bearing phase,enriched in fluorine.The coupled dissolution-precipitation processes during the magmatic-hydrothermal transition play a critical role in the remobilization and enrichment of rare elements such as Li,Nb,Ta,and Sn.This deposit,characterized by spodumene crystallization in the Spd+Quartz stability field(≥300 MPa,≤725℃)and subsequent alteration to Ecr+quartz assemblages(<270℃,<160 MPa),exhibits broader temperature-pressure conditions exceeding typical global pegmatites like Tanco,with no petalite formation observed due to its persistent exclusion from petalite stability fields throughout mineralization.The shear zone controls the pegmatite emplacement and lithium enrichment in the 509 Daobanxi lithium deposit,and its deformation-fluid coupling mechanism provides new insights for the exploration of LCT pegmatite deposits.The present study highlights the importance of understanding both magmatic and hydrothermal processes in the formation of LCT-type pegmatites and provides valuable insights for the exploration of critical metal resources in similar geological settings.
基金Project(51071122)supported by the National Natural Science Foundation of ChinaProject(B08040)supported by the Program of Introducing Talents of Discipline to Universities,China("111"Project)
文摘The precipitation sequence of η（MgZn2） phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy was investigated by examining samples aged at 135 ℃ for various times from 5 min to 6 h. High resolution transmission electron microscopy （HRTEM） observations and energy dispersive X-ray spectroscopy （EDX） analysis indicate that the precipitation sequence of η phase along low-angle grain boundaries should be supersaturated solid solution （SSS）→vacancy-rich clusters （VRC）→GP Ⅱ zones→η＇→η. Based on the theory of non-equilibrium grain boundary segregation （NGS） and non-equilibrium grain boundary co-segregation （NGCS）, the excessive solute elements gradually segregate to the grain boundaries by the diffusion of the solute-vacancy complex during aging treatment. The grain boundary segregation plays an important role in the nucleation and growth of VRC, GP Ⅱ zones, η＇ phase as well as η phase.
基金Supported by National Key Technology R&D program(2006BAD06B06)National Infrastructure of Natural Resources for Science and Technology(2004DKA30460)~~
文摘[Objective] The study was to analyze the phylogenesis of Anas platyrhynchos. [Method] Complete sequence of mitochondrial ND2 gene of 4 Anas platyrhynchos was determined by direct DNA sequencing based on PCR products. Combined with ND2 gene sequences of the Anas Linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [Result] The ND2 gene sequences of 4 Anas platyrhynchos were identical(1 041 bp in length; the nucleotide contents of A, G, T, and C were 28.91%, 13.35%, 20.75% and 36.98% respectively; A+T content approximated to that of C+G). Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ''A". [Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck.
基金supported by grants from the Nature Science Foundation of Shandong Province of China (grant nos.ZR2013CQ024 and ZR2015CM020)
文摘Pathogenic Escherichia coli cause chicken colibacillosis, which is economically devastating to the poultry in- dustry worldwide （Bagheri et al., 2014）. Owing to in- creasing antibiotic resistance, phage therapy reagents have been developed to treat bacterial infections （Xu et al., 2015）.
文摘Enterococci bacteria are important in environmental, food and clinical microbiology. Enterococcus faecium is a nosocomial pathogen that causes bacteremia, endocarditis and other infections. It is among the most prevalent organisms encountered in hospital-associated infections accounting for approximately 12% of nosocomial infections in the USA （Linden and Miller, 1999）. However, certain strains of E. faecium are not only non-pathogenic but also have beneficial effects on human health with probiotic potential. For example, E. faecium T-110 is a consortium member in several probiotic products including BIO-THREE~ which is widely prescribed for human, animal and aqua-cultural use. This strain was originally developed by TOA Pharmaceuticals in Japan, and later used in the probiotic products of several other companies.
基金the financial supports of the National Natural Science Foundation of China(30901030,31372334)the Key Technologies R&D Program of China(2012BAD12B02)the Program for Beijing Excellent Talents,China(2013D009007000003)
文摘Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. However, the outcome of.this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen. The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter （DM）, crude protein （CP）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal. Four multiparous Holstein lactating cows fitted with permanent ruminal cannulas were used. The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals （all in-gradually out method; AG） or were placed in the rumen at designated time points and retrieved at once （gradually in-all out method; GA）. Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability （ED） of DM and CP were significantly higher in the AG compared to the GA method （P〈0.05）. Fractional rates of DM and CP degradation was higher in alfalfa haylage samples incubated in the rumen using the AG method compared to that using the GA method （0.138 h-1 vs. 0.073 h-1 and 0.002 h-1 vs. 0.1125 h-1, for DM and CP, respectively; P〈0.05）. Due to a higher fractional rate of degradation （Kd） of DM and CP, the ED of DM and CP at different fractional passage rates were higher in the AG than those in the GA method （P〈0.05）. Potentially degradable fraction and lag time of NDF were higher in the AG method compared to the GA method （P〈0.05）. Placing all bags in the rumen at once and removing them at designated time intervals compared with introduction of bags in reverse sequence and removing them all at once led to a lower undegradable fraction （U） of NDF in alfalfa （1.8% vs. 4.0%, respectively; P〈0.05） and corn silage （3.3% vs. 6.7%, respectively; P〈0.05） samples. Potentially degradable fraction of ADF was significantly higher in the AG method compared with the GA method （P〈0.05）. Bag incubation sequence had profound effects on kinetics of degradation of DM, CP and NDF in situ in the feed samples studied. The effects were more evident in the forages （especially alfalfa haylage） than in the concentrate ingredientsnamely corn grain and soybean meal..This experiment is the first time to investigate effects of two methods under the same experiment conditions, providing basic data for the determination of ED.
基金Supported by the National Natural Science Foundation of China under Grant No.60772023by the Slpported Project under Grant No.SKLSDE-2010ZX-07 of the State Key Laboratory of Software Development Environment,Beijing University of Aeronautics and As tronautics+2 种基金by the Specialized Research Fund for the Doctoral Program of Higher Educatioi under Grant No.200800130006Chinese Ministry of Education,and by the Innovation Foundation for Ph.D.Graduates under Grant Nos.30-0350 and 30-0366Beijing University of Aeronautics and Astronautics
文摘In this paper, an infinite sequence of conservation laws for a generalized variable-coefficient fifth-order Korteweg-de Vries equation in fluids are constructed based on the Backlund transformation. Hirota bilinear form and symbolic computation are applied to obtain three kinds of solutions. Variable coefficients can affect the conserved density, associated flux, and appearance of the characteristic lines. Effects of the wave number on the soliton structures are also discussed and types of soliton structures, e.g., the double-periodic soliton, parallel soliton and soliton complexes, are presented.
基金Supported by the National Natural Science Foundation of China (10971100)supported by a grant from Postdoctoral Science Research Program of Jiangsu Province (0701049C)+1 种基金the Fundamental Research Funds for the Central Universitiessupported by National Basic Research Program of China (973 Program)(2007CB814800)
文摘The topological pressure for subadditive sequence of discontinuous functions is defined on any invariant subset having a nested family of subsets in the compact metric space. Two subadditive variational principles associated with two different relatively weak conditions are developed for the defined topological pressure. As an application, we give an example on systems with nonzero Lyapunov exponents.
基金supported by grants from the National Program for Basic Research of China(No.2012CB114305)the National Program on High Technology Development(No. 2012AA10A303)the Oversea Graduate Program from Ministry of Education to K.Songyikhangsuthor
文摘Water is a major limiting factor for food production and many countries fail to produce sufficient food for their population due to severe water scarcity （Jury and Vaux, 2005）. Rice is the main staple food worldwide. More than 50% of rice in the world is rain-fed and drought causes severe reduction in rice grain yield in rain-fed environments （Venuprasad et al., 2007; Zhang, 2007; Sandhu et al., 2014）. Therefore, enhancing drought resistance （DR） of rice is important for food security. However, DR is a complex trait, which is controlled by a large number of loci with small effect and is also affected by different genetic background, genotype-by-environment interaction and other stresses such as heat （Hu and Xiong, 2014）.
基金supported by National Science Foundation of China(40002003)
文摘The paper aims to reconstruct the eruption sequence of the permanent teeth of Lufengpithecus lufengensis. Eruption sequence here means the order of appearance of the tooth crowns out of the alveolar crypt. The permanent dental developments of five juvenile mandibles are observed and analyzed via radiograph. Using such records as the stages of crown and root formation, location of the crown occlusion relative to the alveolar margin, and wear degrees of the erupted teeth, the eruption sequence of the mandibular permanent teeth of Lufengpithecus lufengensis is reasonably derived as M1 I1 I2 M2 P3 P4 C M3. This order is seen to differ very markedly from that in modern humans, and to be similar to that in apes.
文摘The idea of difference sequence spaces was introduced in （Klzmaz, 1981） and this concept was generalized in （Et and Colak, 1995）. In this paper we define some difference sequence spaces by a sequence of Orlicz functions and establish some inclusion relations.
文摘The idea of difference sequence sets X（△） = {x = （xk） ： △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence spaces and give some inclusion relations.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.10571137,10771162)
文摘A mechanism for proving global convergence in filter-SQP （sequence of quadratic programming） method with the nonlinear complementarity problem （NCP） function is described for constrained nonlinear optimization problem.We introduce an NCP function into the filter and construct a new SQP-filter algorithm.Such methods are characterized by their use of the dominance concept of multi-objective optimization,instead of a penalty parameter whose adjustment can be problematic.We prove that the algorithm has global convergence and superlinear convergence rates under some mild conditions.
基金Supported by the National Natural Science Foundation of China(Grant Nos.1127102011201004)+2 种基金the Key Project of Chinese Ministry of Education(Grant No.211077)the Natural Science Foundation of Anhui Province(Grant Nos.10040606Q301208085MA11)
文摘In this paper, the complete convergence of weighted sums for ρ＊-mixing sequence of random variables is investigated. By applying moment inequality and truncation methods, the equivalent conditions of complete convergence of weighted sums for ρ＊-mixing sequence of random variables are established. We not only promote and improve the results of Li et al. （J. Theoret. Probab., 1995, 8（1）： 49--76） from i.i.d. to ρ＊-mixing setting but also obtain their necessities and relax their conditions.
基金National Science and Technology Support Program of China(No.2009BAG15B02)Key Programs for Science and Technology Development of Chinese Transportation Industry(No.2008-353-332-190)
文摘Compared to the conventional two-tower suspension bridge, the three-tower suspension bridge has obviously different characteristics in structural performance because of the extra middle tower and main span. The construction sequence for the stiffening girder is significantly different between the three-tower suspension bridge and the two-tower suspension bridge. The tangential angle of the main cable is one of the controlling factors of the stiffening girder erection stage for a suspension bridge. According to 5 feasible cases for the stiffening girder erection scheme in Taizhou Bridge, the research about the tangential angle in each case mentioned above was made, and some factors that should be taken into account for the erection scheme of stiffening girder were pointed out.
文摘The Agrobacterium mediated transgenic rice ( Oryza saliva L.) population with inserts of maize transposon Activator/Dissociation (Ac/Ds) was investigated. DNA sequences flanking the T-DNA were analyzed with inverse PCR. Results showed that 65.4% of the T-DNA was integrated in different locations of rice genome, and some T-DNA flanking sequences were located on certain chromosomes. A number of T-DNA was found to have inserted into protein coding regions. In order to induce transposition of the inserted Ds elements, 354 crosses of Ac x Ds and Ds x Ac were constructed. The excision frequency of Ds element trans-activated by Ac transposase was 22.7% in the F-2 populations, and the transposition was confirmed with analyses of DNA sequences flanking the Ds elements. In addition to the transposition due to 'cut-paste' mechanism, Ds can replicate itself and integrate into a new locus, and inaccurate excisions were also found. A proportion of DNA segments flanking the Ds elements showed no homologies to sequences published in GenBank, of which two were registered under the accession numbers AF355153 and AF355770. The strategy of using transposon tagging for rice genomics study was discussed.
文摘Consider performing a sequence of Bernoulli trials (each resulting in either a success, denoted S, or a failure F, with a probability of p and q := 1 - p respectively) until one of m specific strings (or patterns) of consecutive outcomes is generated. This can be seen as a game where m players select one such pattern each and the one whose pattern occurs first wins. We present symbolic formulas for the m probabilities of winning, and for the mean number of trials and the corresponding standard deviation to complete this game. Several numerical examples are presented, including a search for optimal strategy.
文摘Follow Chen and Duda's model of spectral fall-off of ω~3, the dependence of peak parameters of ground motion, peak displacement d_m, peak velocity vin and peak acceleration a_m, upon the environment stress τ_o-values are studied using near source seismic digital recordings for the sequence of the Wuding, Yunnan, M = 6.5 earthquake, in which, as a new thought, the peak parameters are assumed to be related to the medium Q-value. Three formulae for estimating the environment stress τ_o-values by the peak parameters of three types of ground motions are derived. Using these formulae, the environment stress τ_o-values are calculated for the sequence of the Wuding earthquake. The result show that τ_o-values calculated by the three formulae are constant largely, the averages of τ_o are in the range of 5.0-35 MPa for most earthquakes. It belongs to the high-stress earthquakes sequence: the high-stress values are restricted to the relatively small area closely near to the epicenter of the main shock. The fine distribu tion structure for the contours of the environment stress τ_o-values is related closely to the strong aftershocks. The analysis of spatial and temporal feature of To-values suggests that the earthquakes sequence in a rupture process generated at the specific intersection zone of seismo-tectonics under high-stress background.
文摘 Following China's announcement of its completion of the draft genome sequence of the rice indica subspecies on October 12,2001 (page 126, Bulletin of the Chinese Academy of Sciences Vol. 15 No.3), Chinese scientists published their findings in the April 5 issue of Science, the journal of the American Association for the Advancement of Science (AAAS). In the same issue, a team of scientists with the Switzerland-based Syngenta company reported a similar achievement for another major rice subspecies,japonica.……
文摘The 3.0 kb BglⅡ+XbaⅠrestriction fragment of millet(Setaria italica) chloroplast genome containing rbcL gene had been cloned into pBluescript SK (-) vector, then the restriction map and the 1990 bp complete nucleotide sequence was determined. The 1431 bp coding region of the gene consists of 476 amino acid residues with a predicted molecular weight of 52679 D. The 389 bp 5′ upstream region has the putative -10 box, -35 box and SD sequence, similar to that of procaryotes. The 170 bp 3′ downstream region contains three stem loop structures. Comparison of the rbcL gene sequences between C 4 plants and several C 3 plants reveals no difference in the coding region, promoter and 3′ downstream region. It might be concluded that the rbcL gene sequence has no relation with its cell specific expression.
