pattern of variation
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2021 ◽  
Vol 14 (1) ◽  
pp. 117-129
Author(s):  
Cs. Orbán ◽  
É. Kis ◽  
Cs. Albert ◽  
É. Molnos

Abstract The antioxidant capacity is the combined free radical scavenging effect of all antioxidant compounds found in the studied system. There is a growing need for accurate, numerical determination of this capacity (for easier comparison), so there are many analytical procedures, methods, and measurement systems available to researchers. Neither one is able to model the totality of real, naturally occurring reactions; therefore, conclusions about the antioxidant power of the studied sample can be drawn only after using several methods. In this work, the total phenolic content (TPC) of blackcurrant leaves and buds was determined, and the antioxidant capacity was tested using the DPPH and FRAP assays. 80% methanol was the most effective in the extraction of phenolics followed by 80% ethanol, while for the antioxidant capacity the acetone (50%)/water/acetic acid (2%) mixture proved to be the best. Significant differences were observed between cultivars and sampling dates, but the pattern of variation during the harvest period was similar for all cultivars.


Author(s):  
D. O. Akpootu ◽  

In this study, the monthly averaged daily mean temperature, relative humidity and surface pressure data obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF) during the period of thirty eight (1979 – 2016) years were used to estimate the monthly variation of geopotential and scale heights for Iseyin located in the South Western region of Nigeria. The variations of geopotential and scale heights with the meteorological parameters were investigated. The results revealed that the highest and lowest values of geopotential height were found in the months of March and July with 194.2424 m and 157.3922 m respectively while the highest and lowest values of scale height were found in the months of March and August with 8.8946×〖10〗^3 m and 8.7825×〖10〗^3 m respectively. Furthermore, it is obvious that high values of geopotential height were recorded during the dry season and low values during the rainy season; the scale height shows almost close observation. The variation of geopotential and scale heights with mean temperature depicts a direct relationship while the variation of geopotential and scale heights with atmospheric pressure depicts an inverse relationship. In addition, the variation of geopotential and scale heights with relative humidity shows that an almost opposite pattern of variation was observed in the months from May to October.


2021 ◽  
Author(s):  
Ruipeng Chai ◽  
Jinyan Wang ◽  
Xing Wang ◽  
Jianqiang Wen ◽  
Xuemei Ye ◽  
...  

Abstract Background: Rice blast (causative agent the fungus Pyricularia oryzae) represents a major constraint over the productivity of one of the world’s most important staple foods. Genes encoding resistance have been identified in both the indica and japonica subspecies genepools, and combining these within new cultivars represents a rational means of combating the pathogen.Results: In this research, a deeper allele mining was carried out on Pid-2, Pid-3, and Pid-4 by their specific FNP markers in the three panels consisting of 70 indica and 58 japonica cultivars. Within Pid-2, three functional and one non-functional alleles were identified; the former were only identified in indica type entries. At Pid-3, four functional and one non-functional alleles were identified, and once again, all of the former were present in indica type entries. However, the pattern of variation at Pid-4 was rather different: here, the five functional alleles uncovered were dispersed across the japonica type germplasm. Among all the 12 candidate functional alleles, both Pid2-ZS and Pid3-ZS were predominant.Conclusions: Variation in both Pid-2 and Pid-3 appears to have evolved in response to pathogen pressure exerted on indica type cultivars, while that in Pid-4 reflects the interaction between the fungus and the host in japonica type crops. Owning to the founder lineage, ‘Zhenzhuai 11-ZS97’, rather limited genotypes of the Pid family have been effective in both indica and japonica rice groups, of which Pid2-ZS+Pid3-ZS is present in a large proportion of Chinese indica cultivars released since the 1960s.


2021 ◽  
Vol 14 ◽  
pp. 45-50
Author(s):  
Adel Moatti ◽  
Mohammad Reza Amin-Nasseri ◽  
Hamid Zafarani

Earthquakes has been known as a destructive natural disaster. Due to high human casualties and economical losses, earthquake prediction appears critical. The b-value of Gutenberg Richter law has been considered as precursor to earthquake prediction. Temporal variation of b-value before earthquakes equal or greater than Mw = 6.0 has been examined in the south of Iran, the Qeshm island and around of this from 1995 to 2012. Clustering method by the k-means algorithm has been performed to find pattern of variation of b-value. Three clusters are obtained as optimum number of clusters by the Silhouette Index. Before all mentioned earthquakes greater than Mw = 6.0, cluster 1, which is known as a decrease in b-value has been seen. so decreasing b-value before main shocks as distinctive pattern has been considered. Also an approximate time of decrease has been determined.


2021 ◽  
Vol 11 (4) ◽  
pp. 1874
Author(s):  
Rongjun Shu ◽  
Lingwei Kong ◽  
Bingheng Liu ◽  
Juntao Wang

Granite residual soil is one of the most frequently encountered problem soils in tropical regions, whose mechanical behavior heavily depends on the pattern of variation of mean effective stress (p’) during shearing, which can be classified into three categories: increasing-p’, constant-p’, and decreasing-p’. Unfortunately, so far, the stress–strain strength characteristics of granite residual soils have been studied mainly under increasing-p’ stress paths, although it is very likely to encounter stress paths with decreasing p’ in practice, especially in excavation engineering. Moreover, most pertinent research has focused on remolded granite residual soils, whereas undisturbed specimens have not yet received enough attention. In this paper, stress path triaxial tests considering different patterns of variation of mean effective stress were conducted on an undisturbed granite residual soil. Subsequently, a variable termed loading angle was introduced to quantitatively represent stress path. The influences of stress path on the Mohr–Coulomb strength parameters, deformation characteristics, ductility, and shearing stiffness were analyzed, with an emphasis on the role of pattern of variation of mean effective stress. The experimental results show that friction angle of the soil increases while cohesion decreases with the increase in loading angle. The increase in loading angle leads to less volume contraction and smaller failure strain. During shearing, the soil exhibited a less brittle response under stress paths with smaller loading angles. The initial secant shear modulus first decreased and then increased as the loading angle increased, with the minimum shearing stiffness occurring at a certain loading angle lying between 90° and 123.7°.


2021 ◽  
Author(s):  
Deng Xiaoxia ◽  
Buatois Bruno ◽  
Peng Yan-Qiong ◽  
Hui Yu ◽  
Cheng Yufen ◽  
...  

Abstract BackgroundFloral volatiles play an important role in pollinator attraction. This is particularly true in obligate brood site pollination mutualisms. The plants generally produce inconspicuous flowers and depend on odours to attract to their inflorescences specialised pollinators that breed in their floral structures. Little is known about the processes shaping the micro-evolution of these floral odours. Here, we investigate geographic variation of floral odour in an obligate host-specific brood site pollination mutualism where plant and pollinator genetic structures are different, Ficus hirta and its specialised pollinators.ResultsWe evidence progressive geographic divergence of floral odours. The pattern of variation fits plant genetic structure but differs from pollinating insect structuring into species and populations. In our study system, the evolution of receptive floral odour presents a pattern that is not distinguishable from neutral drift that is not canalised by the insects.ConclusionWe propose that this pattern characterises obligate brood site pollination mutualisms in which pollinators are host specific and dispersal is limited. Insects with their short generation times and large population sizes track variation in host receptive inflorescence odours. Plants are the drivers and insects the followers. Strict sense plant-insect co-evolution is not involved. In contrast, stabilizing selection may be at work in more dispersive brood site pollination mutualisms, while pollinators may mediate local interspecific plant floral odour convergence when plant species share local pollinators.


Author(s):  
Martín Fuchs ◽  
María Mercedes Piñango ◽  
Ashwini Deo

AbstractWe present a cognitively grounded analysis of the pattern of variation that underlies the ​use of two aspectual markers in Spanish (the Simple-Present marker, Ana baila ‘Ana dances’, and the Present-Progressive marker, Ana está bailando ‘Ana is dancing’) when they express an event-in-progress reading. This analysis is centered around one fundamental communicative goal, which we term perspectivealignment: the bringing of the hearer’s perspective closer to that of the speaker. Perspective alignment optimizes the tension between two nonlinguistic constraints: Theory of Mind, which gives rise to linguisticexpressivity, and Common Ground, which gives rise to linguisticeconomy. We propose that, linguistically, perspectivealignment capitalizes on lexicalized meanings, such as the progressive meaning, that can bring the hearer to the “here and now”. In Spanish, progressive meaning can be conveyed with the Present-Progressive marker regardless of context. By contrast, if the Simple-Present marker is used for that purpose, it must be in a context of shared perceptual access between speaker and hearer; precisely, a condition that establishes perspectivealignment non-linguistically. Support for this analysis comes from a previously observed yet unexplained pattern of contextually-determined variation for the use of the Simple-Present marker in Iberian and Rioplatense (vs. Mexican) Spanish—in contrast to the preference across all three varieties for the use of the Present-Progressive marker—to express an event-in-progress reading.


2020 ◽  
Vol 12 (4) ◽  
pp. 661-669
Author(s):  
Sharali Sharma ◽  
Sumit Kumar ◽  
Deepak Singh

Fish is an irreplaceable, highly nutritious aquatic food in a balanced diet. On the contrary, fish can also be a source of metal contamination when ingested in excess through food and water. The aim of the present study was to determine the seasonal variations in the proximate body composition and levels of Na, K, Ca, Fe, Zn, Cu, and Pb in the muscle tissue of three fish species namely, Schizothorax plagiostomus, Schizothorax progastus and Barilius bendelisis dwelling in Central Himalayan river Alaknanda at Srinagar (Garhwal)  in Garhwal Himalaya. The protein (21.01-21.74%) and carbohydrates (2.31-2.69%) were found maximum in summer season in all the studied fishes while lipid was found to be highest during monsoon season in S. plagiostomus (2.73%) and S. progastus (2.70%) and lowest (1.62-1.68%) in the winter season. B. bendelisis showed a different pattern of variation in lipid content being highest (6.32%) during summer and lowest (3.34%) in monsoon season. Significantly (F=5.69, p<0.04) high content of lipid was found in B. bendelisis as compared to S. plagiostomus and S. progastus during the three seasons. Na, Ca, K, and Fe were detected highest during monsoon, Pb, and Cu during summer and Zn during the winter season. However, Pb was not detected in all the fish samples during monsoon season. B. bendelisis was significantly (p<0.001)rich in Na and Ca, S. plagiostomus in K (p<0.01), and S. progastus in Fe (p<0.001) content during all three seasons. Ca was rich among macroelements while Fe among microelements in all the studied fishes. The amount of Zn (1.48-4.55 mg/100g), Cu (0.429-0.869 mg/100g), and Pb (0.117-0.447 mg/100g) were within the permissible limits of International food safety guidelines. The seasonal variations in the parameters are attributed to food availability, temperature changes, fish metabolism, and prevailing environmental conditions. Thus, these cyprinid species were regarded as safe and useful for human consumption.


Author(s):  
EV Balanovska ◽  
VS Petrushenko ◽  
SM Koshel ◽  
EA Pocheshkhova ◽  
DK Chernevskiy ◽  
...  

The lack of information about the frequency of pharmacogenetic markers in Russia impedes the adoption of personalized treatment algorithms originally developed for West European populations. The aim of this paper was to study the distribution of some clinically significant pharmacogenetic markers across Russia. A total of 45 pharmacogenetic markers were selected from a few population genetic datasets, including ADME, drug target and hemostasis-controlling genes. The total number of donors genotyped for these markers was 2,197. The frequencies of these markers were determined for 50 different populations, comprised of 137 ethnic and subethnic groups. A comprehensive pharmacogenetic atlas was created, i.e. a systematic collection of gene geographic maps of frequency variation for 45 pharmacogenetic DNA markers in Russia and its neighbor states. The maps revealed 3 patterns of geographic variation. Clinal variation (a gradient change in frequency along the East-West axis) is observed in the pharmacogenetic markers that follow the main pattern of variation for North Eurasia (13% of the maps). Uniform distribution singles out a group of markers that occur at average frequency in most Russian regions (27% of the maps). Focal variation is observed in the markers that are specific to a certain group of populations and are absent in other regions (60% of the maps). The atlas reveals that the average frequency of the marker and its frequency in individual populations do not indicate the type of its distribution in Russia: a gene geographic map is needed to uncover the pattern of its variation.


Probus ◽  
2020 ◽  
Vol 32 (2) ◽  
pp. 271-302
Author(s):  
Chiara Gianollo

AbstractI analyze the Romance descendants of Latin aliquis ‘some or other’, which are characterized by a complex pattern of variation in the contemporary Romance languages. I account for this variation in terms of diverging diachronic paths, tracing their determinants back to a process taking place between Classical and late Latin. Classical Latin only used aliquis as an epistemic indefinite, expressing ignorance about the identity of the referent. In late Latin a distributional extension is observed, and aliquis starts to be consistently found as an NPI in negative contexts. This multiplicity of uses is transmitted to medieval Romance and represents the prerequisite for contemporary variation. In their further history, some languages continue only one of the two uses. Other languages maintain both, but the meaning contrast comes to be related to a word-order difference. I analyze this difference as a syntactic DP-internal inversion operation, motivated by focus and connected to polarity sensitivity. Significantly, the diachronic path of the Romance descendants of aliquis contributes to our understanding of general mechanisms of semantic change, since it instantiates a cline of development that can be related to varying (hence, diachronically changing) constraints on quantificational domains.


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