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
Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navi...Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.展开更多
From the viewpoint of protocol sequence, analyses are made of the sequence patterns of possible identity authentication protocol under two cases: with or without the trusted third party (TFP). Ten feasible sequence...From the viewpoint of protocol sequence, analyses are made of the sequence patterns of possible identity authentication protocol under two cases: with or without the trusted third party (TFP). Ten feasible sequence patterns of authentication protocol with TIP and 5 sequence patterns without TFP are gained. These gained sequence patterns meet the requirements for identity authentication, and basically cover almost all the authentication protocols with TFP and without TFP at present. All of the sequence patterns gained are classified into unilateral or bilateral authentication. Then, according to the sequence symmetry, several good sequence patterns with TFP are evaluated. The accompolished results can provide a reference to design of new identity authentication protocols.展开更多
The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-...The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-1 genome sequences. By applying the rule inference algorithm RIPPER (Repeated Incremental Pruning to Produce Error Reduction) to multiple sequence alignments of Env sequences from four classes of compiled datasets, we generated four sets of signature patterns. We found that these patterns were able to distinguish southeastern Asian from non- southeastern Asian sequences with 97.5% accuracy, Chinese from non-Chinese sequences with 98.3% accuracy, African from non-African sequences with 88.4% accuracy, and southern African from non-southern African sequences with 91.2% accuracy. These patterns showed different associations with subtypes and with amino acid positions. In addition, some signature patterns were characteristic of the geographic area from which the sample was taken. Amino acid features corresponding to the phylogenetic clustering of HIV-1 sequences were consistent with some of the deduced patterns. Using a combination of patterns inferred from subtypes B, C, and all subtypes chimeric with CRF01_AE worldwide, we found that signature patterns of subtype C were extremely common in some sampled countries (for example, Zambia in southern Africa), which may hint at the origin of this HIV-1 subtype and the need to pay special attention to this area of Africa. Signature patterns of subtype B sequences were associated with different countries. Even more, there are distinct patterns at single position 21 with glycine, leucine and isoleucine corresponding to subtype C, B and all possible recombination forms chimeric with CRF01_AE, which also indicate distinct geographic features. Our method widens the scope of inference of signature from geographic, genetic, and genomic viewpoints. These findings may provide a valuable reference for epidemiological research or vaccine design.展开更多
Within a time distribution of magnitude values, before any mainshock some earthquake triggering patterns with several features develop, under tectonic processes’ influence, through which it is possible to early ident...Within a time distribution of magnitude values, before any mainshock some earthquake triggering patterns with several features develop, under tectonic processes’ influence, through which it is possible to early identify the preparation phase of big earthquakes. The purpose of this article was to identify and classify the warning patterns that develop before a big earthquake by considering space-time seismicity variations. The methodological approach adopted was of graphical type, based on procedures of technical analysis currently used to estimate the financial markets. In the initial phase of the study we have analyzed the seismic sequences types described in the bibliography (type 1: foreshocks-mainshock-aftershocks, type 2: mainshock-aftershock;type 3: swarm) and the main structure of the seismic cycle, within which maximum and minimum magnitude values characterize the pattern that it develops until the main event changes. Then, we assessed the position of foreshocks, mainshock and aftershocks within the seismic cycle in order to identify the warning pattern that characterized the exact time when the energy emission occurs. As to the evolution normally shown over time, we have grouped the warning patterns in 2 categories: 1) progressive earthquake pattern;2) flash earthquake pattern. Finally, we have made a classification of the warning pattern related to the fluctuations of maximum and minimum magnitude values, compared its form with the mainshock’s focal mechanism and suggested some graphic procedures in order to estimate the mainshock magnitude value associated with each warning pattern. The results we obtained unquestionably allow a better comprehension of preparation process of a large earthquake, improving the earthquakes forecasting probability in the next future.展开更多
We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of...We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of beneficial mutations can be high in general and the same mutation can be either advantageous or deleterious depending on the pattern’s context. The model allows to treat positional information as a physical quantity, formulate its conservation law and to model its continuous evolution in a whole genome, with meaningful applications of basic physical principles such as optimal efficiency and channel capacity. A plausible example of optimal solution analytically describes phase transitions-like behavior. The model shows that, in principle, it is possible to store error-free information on sequences with arbitrary low conservation. The described theoretical framework allows one to approach from novel general perspectives such long-standing paradoxes as excessive junk DNA in large genomes or the corresponding G- and C-values paradoxes. We also expect it to have an effect on a number of fundamental concepts in population genetics including the neutral theory, cost-of-selection dilemma, error catastrophe and others.展开更多
Based on 294 earthquake sequences with magnitude greater than or equal to 5.0 occurred in Chinese mainland since 1970, the spatial distribution features of sequence types have been studied. In southwestern China, it t...Based on 294 earthquake sequences with magnitude greater than or equal to 5.0 occurred in Chinese mainland since 1970, the spatial distribution features of sequence types have been studied. In southwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in Chuan-Dian rhombic block and concerned Xianshuihe-Anninghe-Xiaojiang seismic belt, as well as in Jinshajiang-Honghe seismic belt. Multiple mainshock type (MMT) mainly distributes in western Yunnan, and Longlin and Lancang areas in Tengchong-Baoshan block in west of Nujiang-Lancangjiang fault zone. A few isolated earthquake type (IET) mainly occurred in northwestern Sichuan and there is no IET occurred in Yunnan region. In northwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in west segment of South Tianshan in Xinjiang region. Some MMT also occurred in this area in the intersection of Kalpin block and the Puchang fault zone. It takes IET as the major in middle Tianshan in Xinjiang. Along the Qilianshan seismic belt, most of sequences are MAT. In Qinghai region, it takes MAT as the major, but the regional feature of the spatial distribution of sequence types is not very clear. In North China, it takes MAT as the major in Yinshan-Yanshan-Bohai seismic belt, north edge of North China, and in Hebei plain seismic belt, as well as in sub-plate of lower river area of Yangtze River. In intersection of north segment of Shanxi seismic belt and the NW-trending Yinshan-Yanshan-Bohai seismic belt, there are several moderate or strong MMT with magnitude from 5.0 to 6.0 occurred. In south of North China around the latitude line of 35°N, it takes IET as the major. The spatial distribution of sequence types is relevant to the patterns of tectonic movements. MAT is mostly produced by the ruptures of locked units or asperities or the neonatal separating segments inside the fault zones. MMT is generally relevant to the conjugate structures or intersection of many tectonic settings. Further extension of simple fault often produces IET. Spatial distribution of sequence types is also correlative to the regional and deep environment of crustal medium to some extent. MAT mainly distributes in high velocity area in upper crust or in the transition zone between high velocity area and low velocity area, MMT mostly occurred in the low velocity area in upper crust.展开更多
The basin filling geometric pattern of volcanic eruptive rocks depends on both of the eruptive locations in a basin and structural styles of fault terraces. It is divided into three types by eruptive locations and occ...The basin filling geometric pattern of volcanic eruptive rocks depends on both of the eruptive locations in a basin and structural styles of fault terraces. It is divided into three types by eruptive locations and occurrences of eruptive rocks, including the pattern of eruption along fault and occurrence (PEAFO), the pattern of eruption on footwall of a fault and occurrence (PEOFO) and the pattern of eruption on hangingwall of fault and occurrence (PEOHO) in Xujiaweizi fault depression of Songliao basin, Northeast of China. Those basin filling patterns of volcanic eruptive rocks are of specific geometric characteristics controlling or affecting sedimentation, geometry of sedimentary body and sequence architecture during a sequence evolution. The study shows that the volcanic rocks developed at different stages of lowstand, transgressive and highstand can give different controls or affects on the sequence architecture.展开更多
Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accessio...Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice.展开更多
Active Motif Finder (AMF) is a novel algorithmic tool, designed based on mutations in DNA sequences. Tools available at present for finding motifs are based on matching a given motif in the query sequence. AMF descr...Active Motif Finder (AMF) is a novel algorithmic tool, designed based on mutations in DNA sequences. Tools available at present for finding motifs are based on matching a given motif in the query sequence. AMF describes a new algorithm that identifies the occurrences of patterns which possess all kinds of mutations like insertion, deletion and mismatch. The algorithm is mainly based on the Alignment Score Matrix (ASM) computation by com paring input motif with full length sequence. Much of the effort in bioinformatics is directed to identify these motifs in the sequences of newly discovered genes. The proposed bio-tool serves as an open resource for analysis and useful for studying polymorphisms in DNA sequences. AMF can be searched via a user-friendly interface. This tool is intended to serve the scientific community working in the areas of chemical and structural biology, and is freely available to all users, at http://www.sastra.edu/scbt/amf/.展开更多
This paper, first, analyzed the seismic activity patterns of the Datong-Yanggao earthquake sequence by 4 stages,finding that three times earthquakes of Mis were located in a same NNE seismically active zone and two ti...This paper, first, analyzed the seismic activity patterns of the Datong-Yanggao earthquake sequence by 4 stages,finding that three times earthquakes of Mis were located in a same NNE seismically active zone and two times located in 2 NWW seismically active zones. Then the focal-mechanism solutions of 12 earthquakes of M≥4 and 114 earthquakes of M≥1. 0 in various zones were obtained, a tectonic analysis was made for these data, the obtained fracture characteristic of this sequence is: the conjugate fracture combination with the NNE right lateral faults as its trunk and the two NWW left lateral faults as its branches. Finally, it is pointed out that there is an obvious difference between the seismic fracture and the tensile dip-slip tectonic activity of the main body of the seismic region.展开更多
A 3-D electrostatic density map generated using the Wavefront Topology System and Finite Element Method clearly demonstrates the non-uniformity and periodicity present in even a single loop of an α-helix. The four di...A 3-D electrostatic density map generated using the Wavefront Topology System and Finite Element Method clearly demonstrates the non-uniformity and periodicity present in even a single loop of an α-helix. The four dihedral angles (N-C*-C-N, C*-C-N-C*, and C-N-C*-C) fully define a helical shape independent of its length: the three dihedral angles, φ = -33.5°, ω = 177.3°, and Ψ = -69.4°, generate the precise (and identical) redundancy in a one loop (or longer) α-helical shape (pitch = 1.59 /residue;r = 2.25 ). Nevertheless the pattern of dihedral angles within an 11 and a 22-peptide backbone atom sequence cannot be distributed evenly because the stoichiometry in fraction of four atoms never divides evenly into 11 or 22 backbone atoms. Thus, three sequential sets of 11 backbone atoms in an α-helix will have a discretely different chemical formula and correspondingly different combinations of molecular forces depending upon the assigned starting atom in an 11-step sequence. We propose that the unit cell of one loop of an α-helix occurs in the peptide backbone sequence C-(N-C*-C)3-N which contains an odd number of C* plus even number of amide groups. A two-loop pattern (C*-C-N)7-C* contains an even number of C* atoms plus an odd number of amide groups. Dividing the two-loop pattern into two equal lengths, one fraction will have an extra half amide (N-H) and the other fraction will have an extra half amide C=O, i.e., the stoichiometry of each half will be different. Also, since the length of N-C*-C-N, C*-C-N-C*, and C-N-C*-C are unequal, the summation of the number of each in any fraction of n loops of an α-helix in sequence will always have unequal length, depending upon the starting atom (N, C*, or C).展开更多
Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from dupli...Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from duplication. As one of the six popular folds (super-folds) possessing an approximate structural symmetry, the triosephosphate isomerase barrel (TIM-barrel) domain has been widely studied. Using modified recurrent quantification analysis of primary sequences, we identified the same 2-, 3-, and 4-fold symmetry pattern as their tertiary structures. This result indicates that the symmetry in tertiary structure is coded by symmetry in the primary sequence and that the TIM-barrel adopts a 2-, 3-, or 4-fold repeat pattern during evolution. This discovery will be useful for understanding the evolutionary mechanisms of this protein family and the symmetry pattern that may be a clue into the ancient origin of duplication of half-barrels or the β a unit.展开更多
Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an...Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an approach for generating a pseudo-random multi-value sequence (including a binary sequence) by utilizing a primitive polynomial, trace function, and k-th power residue symbol over the sub extension field. All our previous sequences are defined over the prime field, whereas, proposed sequence in this paper is defined over the sub extension field. Thus, it’s a new and innovative perception to consider the sub extension field during the sequence generation procedure. By considering the sub extension field, two notable outcomes are: proposed sequence holds higher linear complexity and more uniform distribution of bit patterns compared to our previous work which defined over the prime field. Additionally, other important properties of the proposed multi-value sequence such as period, autocorrelation, and cross-correlation are theoretically shown along with some experimental results.展开更多
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.
基金Project(2011CB707102)supported by the National Basic Research Program of ChinaProjects(40901220,41001302)supported by the National Natural Science Foundation of China+1 种基金Project(122025)supported by Fok Ying Tong Education Foundation,ChinaProject(N100401009)supported by Fundamental Research Funds for Central Universities,China
文摘Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.
文摘From the viewpoint of protocol sequence, analyses are made of the sequence patterns of possible identity authentication protocol under two cases: with or without the trusted third party (TFP). Ten feasible sequence patterns of authentication protocol with TIP and 5 sequence patterns without TFP are gained. These gained sequence patterns meet the requirements for identity authentication, and basically cover almost all the authentication protocols with TFP and without TFP at present. All of the sequence patterns gained are classified into unilateral or bilateral authentication. Then, according to the sequence symmetry, several good sequence patterns with TFP are evaluated. The accompolished results can provide a reference to design of new identity authentication protocols.
基金the funding by the Chinese Key National Science and Technology Program in the 12th Five-Year Period, grant 2012ZX10001006-002
文摘The epidemiology of HIV-1 varies in different areas of the world, and it is possible that this complexity may leave unique footprints in the viral genome. Thus, we attempted to find significant patterns in global HIV-1 genome sequences. By applying the rule inference algorithm RIPPER (Repeated Incremental Pruning to Produce Error Reduction) to multiple sequence alignments of Env sequences from four classes of compiled datasets, we generated four sets of signature patterns. We found that these patterns were able to distinguish southeastern Asian from non- southeastern Asian sequences with 97.5% accuracy, Chinese from non-Chinese sequences with 98.3% accuracy, African from non-African sequences with 88.4% accuracy, and southern African from non-southern African sequences with 91.2% accuracy. These patterns showed different associations with subtypes and with amino acid positions. In addition, some signature patterns were characteristic of the geographic area from which the sample was taken. Amino acid features corresponding to the phylogenetic clustering of HIV-1 sequences were consistent with some of the deduced patterns. Using a combination of patterns inferred from subtypes B, C, and all subtypes chimeric with CRF01_AE worldwide, we found that signature patterns of subtype C were extremely common in some sampled countries (for example, Zambia in southern Africa), which may hint at the origin of this HIV-1 subtype and the need to pay special attention to this area of Africa. Signature patterns of subtype B sequences were associated with different countries. Even more, there are distinct patterns at single position 21 with glycine, leucine and isoleucine corresponding to subtype C, B and all possible recombination forms chimeric with CRF01_AE, which also indicate distinct geographic features. Our method widens the scope of inference of signature from geographic, genetic, and genomic viewpoints. These findings may provide a valuable reference for epidemiological research or vaccine design.
文摘Within a time distribution of magnitude values, before any mainshock some earthquake triggering patterns with several features develop, under tectonic processes’ influence, through which it is possible to early identify the preparation phase of big earthquakes. The purpose of this article was to identify and classify the warning patterns that develop before a big earthquake by considering space-time seismicity variations. The methodological approach adopted was of graphical type, based on procedures of technical analysis currently used to estimate the financial markets. In the initial phase of the study we have analyzed the seismic sequences types described in the bibliography (type 1: foreshocks-mainshock-aftershocks, type 2: mainshock-aftershock;type 3: swarm) and the main structure of the seismic cycle, within which maximum and minimum magnitude values characterize the pattern that it develops until the main event changes. Then, we assessed the position of foreshocks, mainshock and aftershocks within the seismic cycle in order to identify the warning pattern that characterized the exact time when the energy emission occurs. As to the evolution normally shown over time, we have grouped the warning patterns in 2 categories: 1) progressive earthquake pattern;2) flash earthquake pattern. Finally, we have made a classification of the warning pattern related to the fluctuations of maximum and minimum magnitude values, compared its form with the mainshock’s focal mechanism and suggested some graphic procedures in order to estimate the mainshock magnitude value associated with each warning pattern. The results we obtained unquestionably allow a better comprehension of preparation process of a large earthquake, improving the earthquakes forecasting probability in the next future.
文摘We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of beneficial mutations can be high in general and the same mutation can be either advantageous or deleterious depending on the pattern’s context. The model allows to treat positional information as a physical quantity, formulate its conservation law and to model its continuous evolution in a whole genome, with meaningful applications of basic physical principles such as optimal efficiency and channel capacity. A plausible example of optimal solution analytically describes phase transitions-like behavior. The model shows that, in principle, it is possible to store error-free information on sequences with arbitrary low conservation. The described theoretical framework allows one to approach from novel general perspectives such long-standing paradoxes as excessive junk DNA in large genomes or the corresponding G- and C-values paradoxes. We also expect it to have an effect on a number of fundamental concepts in population genetics including the neutral theory, cost-of-selection dilemma, error catastrophe and others.
基金Joint Seismological Science Foundation of China (105076) and continued subject ″Statistic Features of Aftershock Sequences and Forecast of the Large Aftershocks″ (2004BA601B01-04-02), Ministry of Science and Technology of China in the 10th Five-Year Plan.
文摘Based on 294 earthquake sequences with magnitude greater than or equal to 5.0 occurred in Chinese mainland since 1970, the spatial distribution features of sequence types have been studied. In southwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in Chuan-Dian rhombic block and concerned Xianshuihe-Anninghe-Xiaojiang seismic belt, as well as in Jinshajiang-Honghe seismic belt. Multiple mainshock type (MMT) mainly distributes in western Yunnan, and Longlin and Lancang areas in Tengchong-Baoshan block in west of Nujiang-Lancangjiang fault zone. A few isolated earthquake type (IET) mainly occurred in northwestern Sichuan and there is no IET occurred in Yunnan region. In northwestern China, it takes mainshock-aftershock sequence type (MAT) as the major in west segment of South Tianshan in Xinjiang region. Some MMT also occurred in this area in the intersection of Kalpin block and the Puchang fault zone. It takes IET as the major in middle Tianshan in Xinjiang. Along the Qilianshan seismic belt, most of sequences are MAT. In Qinghai region, it takes MAT as the major, but the regional feature of the spatial distribution of sequence types is not very clear. In North China, it takes MAT as the major in Yinshan-Yanshan-Bohai seismic belt, north edge of North China, and in Hebei plain seismic belt, as well as in sub-plate of lower river area of Yangtze River. In intersection of north segment of Shanxi seismic belt and the NW-trending Yinshan-Yanshan-Bohai seismic belt, there are several moderate or strong MMT with magnitude from 5.0 to 6.0 occurred. In south of North China around the latitude line of 35°N, it takes IET as the major. The spatial distribution of sequence types is relevant to the patterns of tectonic movements. MAT is mostly produced by the ruptures of locked units or asperities or the neonatal separating segments inside the fault zones. MMT is generally relevant to the conjugate structures or intersection of many tectonic settings. Further extension of simple fault often produces IET. Spatial distribution of sequence types is also correlative to the regional and deep environment of crustal medium to some extent. MAT mainly distributes in high velocity area in upper crust or in the transition zone between high velocity area and low velocity area, MMT mostly occurred in the low velocity area in upper crust.
文摘The basin filling geometric pattern of volcanic eruptive rocks depends on both of the eruptive locations in a basin and structural styles of fault terraces. It is divided into three types by eruptive locations and occurrences of eruptive rocks, including the pattern of eruption along fault and occurrence (PEAFO), the pattern of eruption on footwall of a fault and occurrence (PEOFO) and the pattern of eruption on hangingwall of fault and occurrence (PEOHO) in Xujiaweizi fault depression of Songliao basin, Northeast of China. Those basin filling patterns of volcanic eruptive rocks are of specific geometric characteristics controlling or affecting sedimentation, geometry of sedimentary body and sequence architecture during a sequence evolution. The study shows that the volcanic rocks developed at different stages of lowstand, transgressive and highstand can give different controls or affects on the sequence architecture.
文摘Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice.
文摘Active Motif Finder (AMF) is a novel algorithmic tool, designed based on mutations in DNA sequences. Tools available at present for finding motifs are based on matching a given motif in the query sequence. AMF describes a new algorithm that identifies the occurrences of patterns which possess all kinds of mutations like insertion, deletion and mismatch. The algorithm is mainly based on the Alignment Score Matrix (ASM) computation by com paring input motif with full length sequence. Much of the effort in bioinformatics is directed to identify these motifs in the sequences of newly discovered genes. The proposed bio-tool serves as an open resource for analysis and useful for studying polymorphisms in DNA sequences. AMF can be searched via a user-friendly interface. This tool is intended to serve the scientific community working in the areas of chemical and structural biology, and is freely available to all users, at http://www.sastra.edu/scbt/amf/.
文摘This paper, first, analyzed the seismic activity patterns of the Datong-Yanggao earthquake sequence by 4 stages,finding that three times earthquakes of Mis were located in a same NNE seismically active zone and two times located in 2 NWW seismically active zones. Then the focal-mechanism solutions of 12 earthquakes of M≥4 and 114 earthquakes of M≥1. 0 in various zones were obtained, a tectonic analysis was made for these data, the obtained fracture characteristic of this sequence is: the conjugate fracture combination with the NNE right lateral faults as its trunk and the two NWW left lateral faults as its branches. Finally, it is pointed out that there is an obvious difference between the seismic fracture and the tensile dip-slip tectonic activity of the main body of the seismic region.
文摘A 3-D electrostatic density map generated using the Wavefront Topology System and Finite Element Method clearly demonstrates the non-uniformity and periodicity present in even a single loop of an α-helix. The four dihedral angles (N-C*-C-N, C*-C-N-C*, and C-N-C*-C) fully define a helical shape independent of its length: the three dihedral angles, φ = -33.5°, ω = 177.3°, and Ψ = -69.4°, generate the precise (and identical) redundancy in a one loop (or longer) α-helical shape (pitch = 1.59 /residue;r = 2.25 ). Nevertheless the pattern of dihedral angles within an 11 and a 22-peptide backbone atom sequence cannot be distributed evenly because the stoichiometry in fraction of four atoms never divides evenly into 11 or 22 backbone atoms. Thus, three sequential sets of 11 backbone atoms in an α-helix will have a discretely different chemical formula and correspondingly different combinations of molecular forces depending upon the assigned starting atom in an 11-step sequence. We propose that the unit cell of one loop of an α-helix occurs in the peptide backbone sequence C-(N-C*-C)3-N which contains an odd number of C* plus even number of amide groups. A two-loop pattern (C*-C-N)7-C* contains an even number of C* atoms plus an odd number of amide groups. Dividing the two-loop pattern into two equal lengths, one fraction will have an extra half amide (N-H) and the other fraction will have an extra half amide C=O, i.e., the stoichiometry of each half will be different. Also, since the length of N-C*-C-N, C*-C-N-C*, and C-N-C*-C are unequal, the summation of the number of each in any fraction of n loops of an α-helix in sequence will always have unequal length, depending upon the starting atom (N, C*, or C).
文摘Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from duplication. As one of the six popular folds (super-folds) possessing an approximate structural symmetry, the triosephosphate isomerase barrel (TIM-barrel) domain has been widely studied. Using modified recurrent quantification analysis of primary sequences, we identified the same 2-, 3-, and 4-fold symmetry pattern as their tertiary structures. This result indicates that the symmetry in tertiary structure is coded by symmetry in the primary sequence and that the TIM-barrel adopts a 2-, 3-, or 4-fold repeat pattern during evolution. This discovery will be useful for understanding the evolutionary mechanisms of this protein family and the symmetry pattern that may be a clue into the ancient origin of duplication of half-barrels or the β a unit.
文摘Pseudo-random sequences with long period, low correlation, high linear complexity, and uniform distribution of bit patterns are widely used in the field of information security and cryptography. This paper proposes an approach for generating a pseudo-random multi-value sequence (including a binary sequence) by utilizing a primitive polynomial, trace function, and k-th power residue symbol over the sub extension field. All our previous sequences are defined over the prime field, whereas, proposed sequence in this paper is defined over the sub extension field. Thus, it’s a new and innovative perception to consider the sub extension field during the sequence generation procedure. By considering the sub extension field, two notable outcomes are: proposed sequence holds higher linear complexity and more uniform distribution of bit patterns compared to our previous work which defined over the prime field. Additionally, other important properties of the proposed multi-value sequence such as period, autocorrelation, and cross-correlation are theoretically shown along with some experimental results.