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Evolution of the Madrean-Tethyan disjunctions and the North and South American amphitropical disjunctions in plants 被引量:11
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作者 Jun WEN Stefanie M. ICKERT-BOND 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期331-348,共18页
The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- T... The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- Tethyan disjunctions); and (ii) between the temperate regions of North and South America (the amphitropical disjunctions). Both disjunct patterns have multiple times of origin. The amphitropical disjunctions have largely resulted from long-distance dispersal, primarily from the Miocene to the Holocene, with available data indicating that most lineages dispersed from North to South America. Results of recent studies on the Mediterranean disjuncts between the deserts of Eurasia and western North America support the multiple modes of origin and are mostly consistent with hypotheses of long-distance dispersal and the North Atlantic migration. Axelrod's Madrean-Tethyan hypothesis, which implies vicariance between the two regions in the early Tertiary, has been favored by a few studies. The Beringian migration corridor for semiarid taxa is also supported in some cases. 展开更多
关键词 amphitropical disjunctions BIOGEOGRAPHY Madrean-Tethyan disjunctions Mediterranean disjuncts North-South American disjunctions.
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Phylogenetic analysis of Toxicodendron(Anacardiaceae) and its biogeographic implications on the evolution of north temperate and tropical intercontinental disjunctions 被引量:6
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作者 Ze-Long NIE Hang SUN +1 位作者 Ying MENG Jun WEN 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期416-430,共15页
Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America, extending to southeastern Asia and the neotropics. Nuclear (internal transcribed spac... Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America, extending to southeastern Asia and the neotropics. Nuclear (internal transcribed spacer, external transcribed spacer, and NIA-i3) and chloroplast (ndhF and trnL-F) sequences were used to construct phylogenetic relationships of Toxicodendron. Phylogenetic analysis of these data strongly support Toxieodendron as a monophyletic group distinct from other genera of the Rhus complex, and the phylogeny does not fully corroborate classification at the sectional level. Two temperate disjunct lineages were detected, one from section Toxicodendron and the other between the eastern North American Toxicodendron vernix and the eastern Asian Toxicodendron vernieifluum. Their divergence times were estimated to be 13.46 (7.95-19.42) and 7.53 (2.76-12.86) mya, respectively. The disjunction between section Griffithii (taxa from warm temperate to tropical Asia) and Toxieodendron striatum (from the neotropics) was supported and their divergence time was estimated to be 20.84 (11.1 6-30.52) mya in the early Miocene. Our biogeographic results and the paleontological data support the Bering land bridge as the most likely route to explain the temperate disjunctions, yet the tropical disjunction in Toxicodendron seems to be best explained by the North Atlantic land bridge hypothesis. 展开更多
关键词 ANACARDIACEAE biogeography DISJUNCTION eastern Asia NEOTROPICS North America PHYLOGENETICS Toxicodendron.
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Symphyseal Disjunction after Dystocic Vaginal Delivery: About Two Cases at the SourôSanou University Hospital of Bobo-Dioulasso (CHUSS)
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作者 Millogo Jean De La Croix Sanou Jean de Dieu +7 位作者 Gadigbé Akofa Méré Godé Sabi Tokobou William Ouédraogo André Togbé Eric Serge Alihonou Yaméogo Rélwendé Barnabé Dembélé Adama Somé Der Adolphe Ouattara Souleymane 《Open Journal of Obstetrics and Gynecology》 2024年第1期1-6,共6页
Diastasis of the symphysis pubis is a rare postpartum complication. We report two cases of symphysis diastasis after dystocic delivery, in two patients who presented in the postpartum period with functional impotence,... Diastasis of the symphysis pubis is a rare postpartum complication. We report two cases of symphysis diastasis after dystocic delivery, in two patients who presented in the postpartum period with functional impotence, pubalgia and acute urine retention. A frontal radiograph of the pelvis confirmed the diagnosis, showing a symphyseal separation of 12 mm and 18 mm. In our case, management was mainly medical, with a favorable clinical outcome. 展开更多
关键词 PELVIS Symphyseal Disjunction/Diastasis POST-PARTUM Burkina Faso
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Phylogenetic diversity of eastern Asia-eastern North America disjunct plants is mainly associated with divergence time
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作者 Han-Yang Lin Miao Sun +6 位作者 Ya-Jun Hao Daijiang Li Matthew A.Gitzendanner Cheng-Xin Fu Douglas E.Soltis Pamela S.Soltis Yun-Peng Zhao 《Plant Diversity》 SCIE CAS CSCD 2023年第1期27-35,共9页
The underlying causes of biodiversity disparities among geographic regions have long been a fundamental theme in ecology and evolution.However,the patterns of phylogenetic diversity(PD) and phylogenetic beta diversity... The underlying causes of biodiversity disparities among geographic regions have long been a fundamental theme in ecology and evolution.However,the patterns of phylogenetic diversity(PD) and phylogenetic beta diversity(PBD) of congeners that are disjunctly distributed between eastern Asia-eastern North America(EA-ENA disjuncts) and their associated factors remain unknown.Here we investigated the standardized effect size of PD(SES-PD),PBD,and potentially associated factors in 11natural mixed forest sites(five in EA and six in ENA) where abundant EA-ENA disjuncts occur.We found that the disjuncts in ENA possessed higher SES-PD than those in EA at the continental scale(1.96vs-1.12),even though the number of disjunct species in ENA is much lower than in EA(128 vs 263).SESPD of the EA-ENA disjuncts tended to decrease with increasing latitude in 11 sites.The latitudinal diversity gradient of SES-PD was stronger in EA sites than in ENA sites.Based on the unweighted unique fraction metric(UniFrac) distance and the phylogenetic community dissimilarity,PBD showed that the two northern sites in EA were more similar to the six-site ENA group than to the remaining southern EA sites.Based on the standardized effect size of mean pairwise distances(SES-MPD),nine of eleven studied sites showed a neutral community structure(-1.96 ≤SES-MPD ≤1.96).Both Pearson’s r and structural equation modeling suggested that SES-PD of the EA-ENA disjuncts was mostly associated with mean divergence time.Moreover,SES-PD of the EA-ENA disjuncts was positively correlated with temperaturerelated climatic factors,although negatively correlated with mean diversification rate and community structure.By applying approaches from phylogenetics and community ecology,our work sheds light on historical patterns of the EA-ENA disjunction and paves the way for further research. 展开更多
关键词 EA-ENA disjuncts Climatic factors Community assembly processes Diversification rate Divergence time Phylogenetic diversity
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Comparative transcriptomes reveal the disjunction adaptive strategy of Thuja species in East Asia and North America
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作者 Ermei Chang Xue Liu +3 位作者 Jiahui Chen Jingyi Sun Shaowei Yang Jianfeng Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1963-1974,共12页
The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis... The genus Thuja is ideal for investigating the genetic basis of the East Asia-North America disjunction.The biogeographical background of the genus is debatable and an adaptive strategy is lacking.Through the analysis and mining of comparative transcriptomes,species differentiation and positively selected genes(PSGs)were identified to provide information for understanding the environmental adaptation strategies of the genus Thuja.De novo assembly yielded 44,397-74,252 unigenes of the five Thuja species with contig N50length ranging from 1,559 to 1,724 bp.Annotations revealed a similar distribution of functional categories among them.Based on the phylogenetic trees constructed using the transcriptome data,T.sutchuenensis was divided first,followed by T.plicata and T.occidentalis.The final differentiation of T.koraiensis and T.standishii formed a clade.Enrichment analysis indicated that the PSGs of the North American Thuja species were involved in plant hormone signal transduction and carbon fixation of photosynthetic organisms pathways.The PSGs of East Asian Thuja were related to phenolic,alkaloid,and terpenoid synthesis,important stress-resistant genes and could increase plant resistance to external environmental stresses.This study discovered numerous aroma synthetic-related PSGs including terpene synthase(TPS)genes and lipid phosphate phosphatase 2(LPP2),associated with the synthetic aroma of T.sutchuenensis.Physiological indicators,such as the contents of soluble sugars,total chlorophyll,total phenolics,and total flavonoids were determined,which are consistent with the PSGs enrichment pathways associated with adaptive strategies in the five Thuja species.The results of this study provide an important basis for future studies on conservation genetics. 展开更多
关键词 Thuja species Comparative transcriptomes East Asia-North America disjunction Specific gene Positively selected gene
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Phylogenetic biogeography and taxonomy of disjunctly distributed bryophytes 被引量:1
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作者 Jochen HEINRICHS Jrn HENTSCHEL +2 位作者 Kathrin FELDBERG Andrea BOMBOSCH Harald SCHNEIDER 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期497-508,共12页
More than 200 research papers on the molecular phylogeny and phylogenetic biogeography ofbryophytes have been published since the beginning of this millenium. These papers corroborated assumptions of a complex genetic... More than 200 research papers on the molecular phylogeny and phylogenetic biogeography ofbryophytes have been published since the beginning of this millenium. These papers corroborated assumptions of a complex genetic structure of morphologically circumscribed bryophytes, and raised reservations against many morphologically justified species concepts, especially within the mosses. However, many molecular studies allowed for corrections and modifications of morphological classification schemes. Several studies reported that the phylogenetic structure of disjunctly distributed bryophyte species reflects their geographical ranges rather than morphological disparities. Molecular data led to new appraisals of distribution ranges and allowed for the reconstruction of refugia and migration routes. Intercontinental ranges of bryophytes are often caused by dispersal rather than geographical vicariance. Many distribution patterns of disjunct bryophytes are likely formed by processes such as short distance dispersal, rare long distance dispersal events, extinction, recolonization and diversification. 展开更多
关键词 BRYOPHYTES cryptic speciation disjunctions divergence time estimates Diversity Arrays Technology DNA sequence variation ISOZYMES molecular phylogeny.
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On Daniel Bell's The Cultural Contradictions of Capitalism 被引量:1
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作者 郭春娟 《海外英语》 2016年第10期118-120,共3页
This article makes a brief introduces to Daniel Bell's The Cultural Contradictions of Capitalism which explores how a bourgeois economy coexists with an anti-bourgeois culture. This article is comprised of four pa... This article makes a brief introduces to Daniel Bell's The Cultural Contradictions of Capitalism which explores how a bourgeois economy coexists with an anti-bourgeois culture. This article is comprised of four parts including the concept of culture、the disjunction of three realms(economics, politics and culture)、the cultural contradictions of capitalism and the evaluation on Daniel Bell's theory. It offers a close look into the inner relation between different spheres in the capitalist society illustrated in Bell's book, and Bell's theory in terms of cultural contradictions of capitalism will be concretely elaborated. 展开更多
关键词 DANIEL BELL The Cultural CONTRADICTIONS of CAPITALISM culture MODERNISM CAPITALISM DISJUNCTION of th
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Evolution of biogeographic disjunction between eastern Asia and North America in Chamaecyparis:Insights from ecological niche models 被引量:2
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作者 Ping Liu Jun wen Tingshuang Yi 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第3期111-116,共6页
The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long deb... The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long debated. Chamaecyparis is a good model to test previous hypotheses about the formation of this disjunct pattern as it contains six species disjunctly distributed in EA, western North America(WNA)and eastern North America(ENA). In this study, we applied ecological niche models to test the formation of the disjunct pattern of Chamaecyparis. The model calibrated with the EA species was able to predict the distribution of eastern NA species well, but not the western NA species. Furthermore, the eastern Asian species were shown to have higher niche overlap with the eastern North American species. The EA species were also shown to share more similar habitats with ENA species than with WNA species in the genus. Chamaecyparis species in WNA experienced a significant niche shift compared with congeneric species. Chamaecyparis had a low number of suitable regions in Europe and the middle and western NA during the Last Glacial Maximum(LGM) period, and became extinct in the former region whereas it retains residual distribution in the latter. The extirpations in western NA and Europe in response to the late Neogene and Quaternary climatic cooling and the more similar habitats between ENA and EA ultimately shaped the current intercontinental disjunct distribution of Chamaecyparis. Both current hypotheses may be also jointly applied to explain more eastern Asian and eastern North American disjunctions observed today. 展开更多
关键词 DISJUNCTION Eastern Asia North America CHAMAECYPARIS Ecological niche models MAXENT
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Review of plant biogeographic studies in Brazil 被引量:1
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作者 Pedro FIASCHI José R.PIRANI 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期477-496,共20页
Molecular phylogenetic studies have become a major area of interest in plant systematics, and their impacts on historical biogeographic hypotheses are not to be disregarded. In Brazil, most historical biogeographic st... Molecular phylogenetic studies have become a major area of interest in plant systematics, and their impacts on historical biogeographic hypotheses are not to be disregarded. In Brazil, most historical biogeographic studies have relied on animal phylogenies, whereas plant biogeographic studies have largely lacked a phylogenetic component, having a limited utility for historical biogeography. That country, however, is of great importance for most biogeographic studies of lowland tropical South America, and it includes areas from a number of biogeographic regions of the continent. Important biogeographic reports have been published as part of phylogenetic studies, taxonomic monographs, and regional accounts for small areas or phytogeographic domains, but the available information is subsequently scattered and sometimes hard to find. In this paper we review some relevant angiosperm biogeographic studies in Brazil. Initially we briefly discuss the importance of other continents as source areas for the South American flora. Then we present a subdivision of Brazil into phytogeographic domains, and we cite studies that have explored the detection of biogeographic units (areas of endemism) and how they are historically related among those domains. Examples of plant taxa that could be used to test some biogeographic hypotheses are provided throughout, as well as taxa that exemplify several patterns of endemism and disjunction in the Brazilian angiosperm flora. 展开更多
关键词 ANGIOSPERMS BIOGEOGRAPHY Brazil DISJUNCTION distribution patterns endemism.
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Effects of taxon sampling on molecular dating for within-genus divergence events,when deep fossils are used for calibration 被引量:1
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作者 Richard I.MILNE 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期383-401,共19页
A universal method of molecular dating that can be applied to all families and genera regardless of their fossil records, or lack thereof, is highly desirable. A possible method for eudicots is to use a large phylogen... A universal method of molecular dating that can be applied to all families and genera regardless of their fossil records, or lack thereof, is highly desirable. A possible method for eudicots is to use a large phylogeny calibrated using deep fossils including tricolpate pollen as a fixed (124 mya) calibration point. This method was used to calculate node ages within three species-poor disjunct basal eudicot genera, Caulophyllum, Podophyllum and Pachysandra, and sensitivity of these ages to effects such as taxon sampling were then quantified. By deleting from one to three accessions related to each genus in 112 different combinations, a confidence range describing variation due only to taxon sampling was generated. Ranges for Caulophyllum, Podophyllum and Pachysandra were 8.4-10.6, 7.6-20.0, and 17.6-25.0 mya, respectively. However, the confidence ranges calculated using bootstrapping were much wider, at 3-19, 0-32 and 11-32 mya, respectively. Furthermore, deleting 10 adjacent taxa had a large effect in Pachysandra only, indicating that undersampling effects are significant among Buxales. Changes to sampling density in neighboring clades, or to the position of the fixed fossil calibration point had small to negligible effects. Non-parametric rate smoothing was more sensitive to taxon sampling effects than was penalized likelihood. The wide range for Podophyllum, compared to the other two genera, was probably due to a high degree of rate heterogeneity within this genus. Confidence ranges calculated by this method could be narrowed by sampling more individuals within the genus of interest, and by sequencing multiple DNA regions from all species in the phylogeny. 展开更多
关键词 basal eudicots fossil calibration molecular dating North America-East Asia disjunction taxon sampling Tertiary relict tricolpate pollen.
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Phylogeny and biogeography of Maianthemum(Asparagaceae:Nolinoideae)revisited with emphasis on its divergence pattern in SW China
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作者 Ran Meng Ying Meng +1 位作者 Yong-Ping Yang Ze-Long Nie 《Plant Diversity》 SCIE CAS CSCD 2021年第2期93-101,共9页
Maianthemum is a genus with more than 35 species from the tribe Polygonateae(Asparagaceae),widely distributed between North to Central Americas and eastern Asia with high diversity in the easternHimalayas to the Hengd... Maianthemum is a genus with more than 35 species from the tribe Polygonateae(Asparagaceae),widely distributed between North to Central Americas and eastern Asia with high diversity in the easternHimalayas to the Hengduan Mountains of SW China.Although most species from SW China form a well-supported clade,phylogenetic relationships within this clade remain unclear.With a broad level of taxon sampling and an extensive character sampling fromeight DNA regions,this study intends to revisit the phylogeny and biogeography of the genus to better understand the divergence patterns of species from SW China.Phylogenetic results suggested the monophyly of Maianthemum with recognition of nine strongly supported clades,but backbone relationships among these clades remained largely uncertain.For the SWChina clade,individuals from the same species are grouped into different lineages.Our results revealed that the fast radiation of the SWChina cladewas occurred in the eastern Himalayas,followed by subsequent radiation in the Hengduan Mountains in the Pliocene.Intercontinental disjunctions of Maianthemum in the Northern Hemisphere appear to have occurred multiple times during the late Miocene to the Pliocene,likely resulted by a combination of both vicariance and long-distance dispersal events. 展开更多
关键词 BIOGEOGRAPHY Eastern Asia Hengduan mountains Intercontinental disjunction Maianthemum North America
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Structure and dendroecology of Thuja occidentalis in disjunct stands south of its contiguous range in the central Appalachian Mountains, USA
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作者 Joshua A. Kincaid 《Forest Ecosystems》 SCIE CSCD 2017年第1期55-65,共11页
Background: Information on forest structure, growth, and disturbance history is essential for effective forest management in a dynamic landscape. Because most of our research concerning the ecology and growth of Thuj... Background: Information on forest structure, growth, and disturbance history is essential for effective forest management in a dynamic landscape. Because most of our research concerning the ecology and growth of Thujo ocddenralis comes from sites in northern portions of its range, highly contextual biotic and abiotic factors that affect the species in more southern locales may not be fully accounted for. This research characterized the structural attributes and growth dynamics of Thuja occidentolis in disjunct forest stands south of its contiguous range margin. Methods: The Thujo occidentalis forests examined in this research were located in the central Appalachian Mountains, USA, approximately 440 km south of the contiguous range margin of the species. Forest structural attributes were characterized in two Thujo occidentalis forest stands, which are rare in the region. Tree-ring chronologies were used to examine the influences of disturbance and climate on the growth of Thuja occidentolis. Results: The forests contained a total of 13 tree species with Thuja occidentalis contributing substantially to the basal area of the sites. Thujo occidentalis stems were absent in the smallest size class, while hardwood species were abundant in the smallest classes. Thuja occidentalis stems also were absent from the 〈 70 years age class. By contrast, Thuja occidentalis snags were abundant within stands. Growth-release events were distributed across the disturbance chronology and generally affected a small number of trees. The Thujo occidentolis tree-ring chronology possessed an interseries correlation of 0.62 and mean sensitivity of 0.25. The correlation between mean temperature and Thuja occidentalis growth was weak and variable. Growth and moisture variables were more strongly correlated, and this relationship was predominantly positive. Conclusions: Structural attributes indicate the forests are in the understory reinitiation stage of forest development. Silvicultural manipulations may be necessary to promote Thujo occidentalis establishment. The sensitivity of Thujo occidentalis to climate appears similar throughout its range, but geographical variation in the growth response to climate factors is apparent. More research is necessary to expand the geographical and ecological scope of our knowledge concerning Thuja occidentalis, particularly at more southern and disjunct sites. 展开更多
关键词 Northern white cedar DISTURBANCE Climate RANGE DISJUNCT Radial growth Regeneration
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Simplicial Indicator Kriging
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作者 R Tolosana-Delgado V Pawlowsky-Glahn J J Egozcue 《Journal of China University of Geosciences》 SCIE CSCD 2008年第1期65-71,共7页
Indicator kriging (IK) is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. The result is a discrete approximation, and its correspondi... Indicator kriging (IK) is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. The result is a discrete approximation, and its corresponding estimated probability density function can be viewed as a composition in the simplex. This fact suggested a compositional approach to IK which, by construction, avoids all its standard drawbacks (negative predictions, not-ordered or larger than one). Here, a simple algorithm to develop the procedure is presented. 展开更多
关键词 Aitchison geometry compositional data disjunctive kriging log-ratio approach simplex.
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An Approach for Handling Conflicts in Authorization
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作者 ZHANG Mingsheng ZHANG Mingyi 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期626-630,共5页
Based on logic programs, authorization conflicts and resolution strategies are analyzed through the explanation of some examples on the health care sector. A resolution scheme for handling conflicts in high level auth... Based on logic programs, authorization conflicts and resolution strategies are analyzed through the explanation of some examples on the health care sector. A resolution scheme for handling conflicts in high level authorization specification by using logic program with ordered disjunction (LPOD) is proposed. The scheme is useful for solving conflicts resulted from combining positive and negative authorization, complexity of authorization management, and less clarity of the specification. It can well specify kinds of conflicts (such as exceptional conflicts, potential conflicts), and is based on literals and dependent contexts. Thus it is expressive and available. It is shown that authorizations based on rules LPOD is very important both in theory and practice. 展开更多
关键词 AUTHORIZATION authorization conflict conflict resolution schema logic program with ordered disjunction
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Modified Shifting Bottleneck Heuristic for Scheduling Problems of Large-Scale Job Shops
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作者 周炳海 彭涛 《Journal of Donghua University(English Edition)》 EI CAS 2016年第6期883-887,共5页
A modified shifting bottleneck algorithm was proposed to solve scheduling problems of a large-scale job shop.Firstly,a new structured algorithm was employed for sub-problems so as to reduce the computational burden an... A modified shifting bottleneck algorithm was proposed to solve scheduling problems of a large-scale job shop.Firstly,a new structured algorithm was employed for sub-problems so as to reduce the computational burden and suit for large-scale instances more effectively.The modified cycle avoidance method,incorporating with the disjunctive graph model and topological sort algorithm,was applied to guaranteeing the feasibility of solutions with considering delayed precedence constraints.Finally,simulation experiments were carried out to verify the feasibility and effectiveness of the modified method.The results demonstrate that the proposed algorithm can solve the large-scale job shop scheduling problems(JSSPs) within a reasonable period of time and obtaining satisfactory solutions simultaneously. 展开更多
关键词 shifting bottleneck algorithm large-scale job shop scheduling disjunctive graph model delayed precedence constraint(DPC) cycle avoidance method
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Some Results on Generalized Degree Distance
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作者 Asma Hamzeh Ali Iranmanesh Samaneh Hossein-Zadeh 《Open Journal of Discrete Mathematics》 2013年第3期143-150,共8页
In [1], Hamzeh, Iranmanesh and Hossein-Zadeh and M. V. Diudea recently introduced the generalized degree distance of graphs. In this paper, we present explicit formulas for this new graph invariant of the Cartesian pr... In [1], Hamzeh, Iranmanesh and Hossein-Zadeh and M. V. Diudea recently introduced the generalized degree distance of graphs. In this paper, we present explicit formulas for this new graph invariant of the Cartesian product, composition, join, disjunction and symmetric difference of graphs and introduce generalized and modified generalized degree distance polynomials of graphs, such that their first derivatives at x = 1 are respectively, equal to the generalized degree distance and the modified generalized degree distance. These polynomials are related to Wiener-type invariant polynomial of graphs. 展开更多
关键词 Generalized Degree DISTANCE CARTESIAN Product JOIN SYMMETRIC DIFFERENCE Composition DISJUNCTION
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A Fuzzy Logic Based Resolution Principal for Approximate Reasoning
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作者 Alex Tserkovny 《Journal of Software Engineering and Applications》 2017年第10期793-823,共31页
In this article, we present a systemic approach toward a fuzzy logic based formalization of an approximate reasoning methodology in a fuzzy resolution, where we derive a truth value of A from both values of B → A and... In this article, we present a systemic approach toward a fuzzy logic based formalization of an approximate reasoning methodology in a fuzzy resolution, where we derive a truth value of A from both values of B → A and B by some mechanism. For this purpose, we utilize a t-norm fuzzy logic, in which an implication operator is a root of both graduated conjunction and disjunction operators. Furthermore by using an inverse approximate reasoning, we conclude the truth value of A from both values of B → A and B, applying an altogether different mechanism. A current research is utilizing an approximate reasoning methodology, which is based on a similarity relation for a fuzzification, while similarity measure is utilized in fuzzy inference mechanism. This approach is applied to both generalized modus-ponens/modus-tollens syllogisms and is well-illustrated with artificial examples. 展开更多
关键词 FUZZY Logic Deduction FUZZY RESOLVENT Implication DISJUNCTION Conjunction ANTECEDENT Consequent Modus-Ponens Modus-Tollens FUZZY Conditional Inference Rule
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三类乘积图的peripheral Wiener指标
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作者 董哈微 《闽南师范大学学报(自然科学版)》 2020年第2期8-12,共5页
顶点v的离心率是v到图中其它顶点的最大距离.Peripheral顶点是具有最大离心率的顶点,图G的peripheral Wiener指标为G中所有peripheral顶点的距离和.给出3种图运算的乘积图的peripheral Wiener指标的计算公式.
关键词 peripheral Wiener指标 corona乘积图 disjunction乘积图 对称差乘积图
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Some Considerations about Fuzzy Logic Based Decision Making by Autonomous Intelligent Actor
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作者 Alex Tserkovny 《Journal of Software Engineering and Applications》 2022年第2期19-58,共40页
The article presents an approach toward an implementation of a fuzzy logic-based decision-making process by Autonomous Intelligent Actor (AIA) (© A. Tserkovny), when an input information is defined for its “stra... The article presents an approach toward an implementation of a fuzzy logic-based decision-making process by Autonomous Intelligent Actor (AIA) (© A. Tserkovny), when an input information is defined for its “strategic targeting” by a human operator in terms of a fuzzy incident geometry, whereas its “tactical” behavior (a navigation in space) is directed by fuzzy conditional inference rules. For implementing both elements of AIA decision-making a fuzzy logic [1] for formal geometric reasoning with extended objects is used. This fuzzy logic based fuzzification of axioms of an incidence geometry and a predicate apparatus [2] for AIA space orientation are also presented. The approach, offered in the article, extends predicates of a counter positioning of two objects and their mutual navigation into their fuzzy counterparts. The latter allows AIA to make certain “tactical” decisions. 展开更多
关键词 Fuzzy Logic Implication Conjunction DISJUNCTION Fuzzy Predicate Degree of Indiscernibility Discernibility Measure Extended Lines Sameness AIA Orientation Principles
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Into Africa via docked India: a fossil climbing perch from the Oligocene of Tibet helps solve the anabantid biogeographical puzzle 被引量:6
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作者 Feixiang Wu Dekui He +1 位作者 Gengyu Fang Tao Deng 《Science Bulletin》 SCIE EI CAS CSCD 2019年第7期455-463,共9页
The northward drift of the Indian Plate and its collision with Eurasia have profoundly impacted the evolutionary history of the terrestrial organisms, especially the ones along the Indian Ocean rim. Climbing perches(A... The northward drift of the Indian Plate and its collision with Eurasia have profoundly impacted the evolutionary history of the terrestrial organisms, especially the ones along the Indian Ocean rim. Climbing perches(Anabantidae) are primary freshwater fishes showing a disjunct south Asian-African distribution,but with an elusive paleobiogeographic history due to the lack of fossil evidence. Here, based on an updated time-calibrated anabantiform phylogeny integrating a number of relevant fossils, the divergence between Asian and African climbing perches is estimated to have occurred in the middle Eocene(ca.40 Ma, Ma: million years ago), a time when India had already joined with Eurasia. The key fossil lineage is ?Eoanabas, the oldest anabantid known so far, from the upper Oligocene of the Tibetan Plateau.Ancestral range reconstructions suggest a Southeast Asian origin in the early Eocene(ca. 48 Ma) and subsequent dispersals to Tibet and then India for this group. Thereby we propose their westbound dispersal to Africa via the biotic bridge between India and Africa. If so, climbing perch precursors had probably followed the paleobiogeographical route of snakehead fishes, which have a slightly older divergence between African and Asian taxa. As such, our study echoes some recent molecular analyses in rejecting the previously held ‘‘Gondwana continental drift vicariance" or late Mesozoic dispersal scenarios for the climbing perches, but provides a unique biogeographical model to highlight the role of the preuplift Tibet and the docked India in shaping the disjunct distribution of some air-breathing freshwater fishes around the Indian Ocean. 展开更多
关键词 CLIMBING PERCHES Asian-African DISJUNCT distribution Biogeography Indian subcontinent TIBET
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