evolutionary characteristic
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2021 ◽  
Vol 3 (9) ◽  
pp. 4-8
Author(s):  
S. V. SOKOLOV ◽  

The article is devoted to the study of human capital as a system. The evolutionary characteristic of the essence of human capital is given on the basis of studying the works of scientists from the middle of the twentieth century to the present time about its nature, components, sources of development and functional features. The conditions of possibility of studying human capital as a system are considered. The presented results of the main methodological provisions of the study of human capital on the basis of a systematic approach can serve as a basis for substantiating the directions of development aimed at increment of human capital of rural areas.



All Life ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 414-427
Author(s):  
Yiwang Tang ◽  
Yunlin Zhao ◽  
Chaoyang Li ◽  
Guiyan Yang ◽  
Jiao Peng ◽  
...  


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Lianghai Jin ◽  
Mei Fang ◽  
Shu Chen ◽  
Wenfan Lei ◽  
Yun Chen

In evacuation, the velocity difference of adjacent pedestrians before and after often leads to tangential change of pedestrian location in channel. This tangential change behavior and its interaction disturb the stable state of crowd evacuation in multiple channels, which can affect the efficiency of crowd evacuation and even cause trampling accidents. This paper considers the dynamic comfort distance and the expected speed and analyzes the relative position changes after pedestrians change lanes. It investigates the conditions of tangential change behavior and defines the rules of tangential change behavior processing. Meanwhile, it investigates the crowd’s tangential change behavior and its interaction process, revealing the crowd evacuation mechanism of tangential change behavior conditions. Simulation results show that as the crowd density gradually increases, pedestrians exhibit the evolutionary characteristic of “no tangential change ⟶ occasional tangential change ⟶ frequent tangential change ⟶ closely following.” The evacuation speed is obviously influenced by pedestrian’s tangential change behavior and crowd density; when the pedestrian density ρ = 2.0 and ρ = 3.0 , the tangential change behavior not only makes the speed difference and fluctuation between different lanes great but also has the same effect on the average speed of pedestrians. The results of this study can provide theoretical insights into the organization of multichannel evacuation and expand the theoretical space of crowd dynamics in an evacuation.



Semantic Web ◽  
2020 ◽  
pp. 1-25
Author(s):  
Andre Gomes Regino ◽  
Julio Cesar dos Reis ◽  
Rodrigo Bonacin ◽  
Ahsan Morshed ◽  
Timos Sellis

RDF data has been extensively deployed describing various types of resources in a structured way. Links between data elements described by RDF models stand for the core of Semantic Web. The rising amount of structured data published in public RDF repositories, also known as Linked Open Data, elucidates the success of the global and unified dataset proposed by the vision of the Semantic Web. Nowadays, semi-automatic algorithms build connections among these datasets by exploring a variety of methods. Interconnected open data demands automatic methods and tools to maintain their consistency over time. The update of linked data is considered as key process due to the evolutionary characteristic of such structured datasets. However, data changing operations might influence well-formed links, which turns difficult to maintain the consistencies of connections over time. In this article, we propose a thorough survey that provides a systematic review of the state of the art in link maintenance in linked open data evolution scenario. We conduct a detailed analysis of the literature for characterising and understanding methods and algorithms responsible for detecting, fixing and updating links between RDF data. Our investigation provides a categorisation of existing approaches as well as describes and discusses existing studies. The results reveal an absence of comprehensive solutions suited to fully detect, warn and automatically maintain the consistency of linked data over time.



2020 ◽  
Vol 14 ◽  
pp. 99-114
Author(s):  
Kesara Anamthawat-Jónsson ◽  
Audrey Pace ◽  
Sigurður H. Árnason

Sea sandwort (Honckenya peploides) was among the first species of vascular plants colonizing Surtsey. It is a member of the carnation family, Caryophyllaceae, a coastal plant with circumpolar distribution. The species is dioecious comprising separate female and hermaphrodite (male) plants. Our previous study of this plant revealed high molecular polymorphism, indicating rapid expansion and multiple origins, but low genetic differentiation, suggesting gene flow on Surtsey. The maintenance and/or expansion of populations with high gene diversity on the island are most likely fostered by several factors, one of them being the polyploid nature of the study species providing fixed heterozygosity. We therefore investigated chromosome number diversity of H. peploides from Surtsey, in comparison with accessions from Heimaey and other locations within and outside Iceland. Seeds were germinated with and without cold stratification. Chromosomes were isolated from root tips using the cellulase-pectinase enzymatic squash method. DAPIstained chromosomes were counted from microscopic images that were taken at 1000x magnification. The results show that the most common 2n somatic chromosome number of this species is 68 (2n=4x=68), but a tetraploid cytotype with 66 chromosomes also exists. The karyotype analysis shows that the species is an autotetraploid, most likely originating via chromosome doubling (whole genome duplication) in a diploid ancestor. Numerous other 2n numbers were discovered, from the diploid number 2n=2x=34 in Heimaey to several different numbers between 40 and 64. The triploid hybrid numbers 2n=3x=51 (50-52) were discovered from both Surtsey and Heimaey, as well as from other regions. Triploid hybrids serve as a bridge promoting gene flow within populations, promoting heterozygosity in the tetraploid species. All other numbers are aneuploids, most likely deriving from back-crossing of triploid hybrids and the euploid parents. The presence of aneuploids across the species distribution range is due to its ability to propagate asexually by clonal expansion. The presence of the lower ploidy levels within species, together with the extensive aneuploidy, may be an evolutionary characteristic of a pioneering plant, with great dispersal ability and genetic diversity, such as sea sandwort.



2018 ◽  
Vol 115 (33) ◽  
pp. E7844-E7853 ◽  
Author(s):  
Hideki Yoshida ◽  
Eiichi Tanimoto ◽  
Takaaki Hirai ◽  
Yohei Miyanoiri ◽  
Rie Mitani ◽  
...  

The plant gibberellin (GA) receptor GID1 shows sequence similarity to carboxylesterase (CXE). Here, we report the molecular evolution of GID1 from establishment to functionally diverse forms in eudicots. By introducing 18 mutagenized rice GID1s into a rice gid1 null mutant, we identified the amino acids crucial for GID1 activity in planta. We focused on two amino acids facing the C2/C3 positions of ent-gibberellane, not shared by lycophytes and euphyllophytes, and found that adjustment of these residues resulted in increased GID1 affinity toward GA4, new acceptance of GA1 and GA3 carrying C13-OH as bioactive ligands, and elimination of inactive GAs. These residues rendered the GA perception system more sophisticated. We conducted phylogenetic analysis of 169 GID1s from 66 plant species and found that, unlike other taxa, nearly all eudicots contain two types of GID1, named A- and B-type. Certain B-type GID1s showed a unique evolutionary characteristic of significantly higher nonsynonymous-to-synonymous divergence in the region determining GA4 affinity. Furthermore, these B-type GID1s were preferentially expressed in the roots of Arabidopsis, soybean, and lettuce and might be involved in root elongation without shoot elongation for adaptive growth under low-temperature stress. Based on these observations, we discuss the establishment and adaption of GID1s during plant evolution.



2016 ◽  
Author(s):  
Richard C. Tillquist ◽  
Lauren G. Shoemaker ◽  
Kevin Bracy Knight ◽  
Aaron Clauset

Body size is a key physiological, ecological, and evolutionary characteristic of species. Within most major clades, body size distributions follow a right-skewed pattern where most species are relatively small while a few are orders of magnitude larger than the median size. Using a novel database of 742 extant and extinct primate species’ sizes over the past 66 million years, we find that primates exhibit the opposite pattern: a left-skewed distribution. We investigate the long-term evolution of this distribution, first showing that the initial size radiation is consistent with plesiadapiformes (an extinct group with an uncertain ancestral relationship to primates) being ancestral to modern primates. We calculate the strength of Cope’s Rule, showing an initial tendency for descendants to increase in size relative to ancestors until the trend reverses 40 million years ago. We explore when the primate size distribution becomes left-skewed and study correlations between body size patterns and climactic trends, showing that across Old and New World radiations the body size distribution initially exhibits a right-skewed pattern. Left-skewness emerged early in Old World primates in a manner consistent with a previously unidentified possible maximum body size, which may be mechanistically related to primates’ encephalization and complex social groups.



2012 ◽  
Vol 204-208 ◽  
pp. 3174-3181
Author(s):  
Ya Fei Ma ◽  
Jian Ren Zhang ◽  
Lei Wang

The prediction of pitting corrosion-induced structural performance degradation is limited by the inspection means and experimental data. Incomplete information and tempral and spatial uncertainties of corrosion are integrated to develop the time-dependent pit depth model. The reinforcement corrosion is divided into two stages in this model. The approach is illustrated by a removed concrete bridge. The evolutionary characteristic of probability density function of the pit depth is analyzed, and the probabilistic distribution pattern and distribution parameters are also obtained. Besides, The sensitivity of input parameters on the pitting model are also discussed. The results show that under appropriate conditions of concrete strength (>25MPa), increase the same percentage of concrete strength is more sensitive to the pit depth than improvement the same percentage of concrete cover thickness. The effects of continuous improvement of concrete strength or increase the thickness on corrosion depth gradually decreases. The proposed procedure can be used to evaluation of existing reinforced concrete bridge.



2010 ◽  
Vol 22 (2) ◽  
pp. 448 ◽  
Author(s):  
Kathleen Roellig ◽  
Frank Goeritz ◽  
Thomas B. Hildebrandt

The European brown hare is one species in which reproduction appears to be particularly complex. Therefore, we studied the reproductive tract and prenatal development using high-resolution ultrasound of 159 pregnancies in 45 captive female hares. Consecutive examination of live hares was particularly useful in evaluating the very early stages of gestation. As such, it was possible to detect corpora lutea by Day 3 and embryonic vesicles, representing the earliest uterine embryonic stages, by Day 6. On Day 11, the heart beat of the embryo was detectable for the first time. We defined ultrasonographic milestones that were characteristic of the different stages of pregnancy. We also calculated growth models using eight different morphological parameters, including development of the corpus luteum. On the basis of these results, it is now possible to estimate the gestational age of a pregnant doe without knowing the date of conception. In contrast with the European rabbit, a distant relative, European hares give birth to precocial young. A comparison of the prenatal growth rate of both species suggests that the precocial state of the hare neonate is a more recently derived evolutionary characteristic, whereas the altricial condition of rabbits represents the ancestral mode.



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