Quantitative characterization, classification and reconstruction of oocyst shapes of Eimeria species from cattle

Parasitology ◽  
1998 ◽  
Vol 116 (1) ◽  
pp. 21-28 ◽  
Author(s):  
C. SOMMER

This study reports on morphological variability of Eimeria species, which may be given either by drawings or as quantitative data. The drawings may be used to facilitate identification by eye of ‘unknown’ Eimeria specimens, whereas quantitative data may serve as a reference set for identification by multivariate statistical techniques. The morphology of 810 Eimeria specimens was defined in binary (b/w) digital images by pixels of their oocyst outline. A Fourier transform of pixel positions yielded size and shape features. To classify coccidia, the quantitative data were employed in an agglomerative clustering by average linkage algorithm with equal weight assigned to size and shape. An inverse Fourier transform served to reconstruct oocyst outlines, i.e. outlines of average shape and size, from mean values of features in resulting clusters. Clusters were subsequently identified based on their average morphology by comparison with drawings of species in an earlier taxonomical work. Five hundred oocyst outlines were simulated for each cluster representing a species, and shape/size variability was presented in contour diagrams. Differences in species shapes, and correspondence in length and width, were seen after reconstruction by inverse Fourier transform and comparison with earlier studies.

Paleobiology ◽  
10.1666/12001 ◽  
2013 ◽  
Vol 39 (3) ◽  
pp. 323-344 ◽  
Author(s):  
Carlo Meloro ◽  
Sarah Elton ◽  
Julien Louys ◽  
Laura C. Bishop ◽  
Peter Ditchfield

Mammalian carnivores are rarely incorporated in paleoenvironmental reconstructions, largely because of their rarity within the fossil record. However, multivariate statistical modeling can be successfully used to quantify specific anatomical features as environmental predictors. Here we explore morphological variability of the humerus in a closely related group of predators (Felidae) to investigate the relationship between morphometric descriptors and habitat categories. We analyze linear measurements of the humerus in three different morphometric combinations (log-transformed, size-free, and ratio), and explore four distinct ways of categorizing habitat adaptations. Open, Mixed, and Closed categories are defined according to criteria based on traditional descriptions of species, distributions, and biome occupancy. Extensive exploratory work is presented using linear discriminant analyses and several fossils are included to provide paleoecological reconstructions.We found no significant differences in the predictive power of distinct morphometric descriptors or habitat criteria, although sample splitting into small and large cat guilds greatly improves the stability of the models. Significant insights emerge for three long-canine cats:Smilodon populator,Paramachairodus orientalis, andDinofelissp. from Olduvai Gorge (East Africa).S. populatorandP. orientalisare both predicted to have been closed-habitat adapted taxa. The false “sabertooth”Dinofelissp. from Olduvai Gorge is predicted to be adapted to mixed habitat. The application of felid humerus ecomorphology to the carnivoran record of Olduvai Gorge shows that the older stratigraphic levels (Bed I, 1.99–1.79 Ma) included a broader range of environments than Beds II or V, where there is an abundance of cats adapted to open environments.


2014 ◽  
Vol 2014 ◽  
pp. 1-24 ◽  
Author(s):  
David W. Pravica ◽  
Njinasoa Randriampiry ◽  
Michael J. Spurr

The family ofnth orderq-Legendre polynomials are introduced. They are shown to be obtainable from the Jacobi theta function and to satisfy recursion relations and multiplicatively advanced differential equations (MADEs) that are analogues of the recursion relations and ODEs satisfied by thenth degree Legendre polynomials. Thenth orderq-Legendre polynomials are shown to have vanishingkth moments for0≤k<n, as does thenth degree truncated Legendre polynomial. Convergence results are obtained, approximations are given, a reciprocal symmetry is shown, and nearly orthonormal frames are constructed. Conditions are given under which a MADE remains a MADE under inverse Fourier transform. This is used to construct new wavelets as solutions of MADEs.


2021 ◽  
Vol 13 (13) ◽  
pp. 7178
Author(s):  
Višnja Mihajlović ◽  
Nenad Grba ◽  
Jan Suđi ◽  
Diane Eichert ◽  
Smilja Krajinović ◽  
...  

This work presents the results of the first Serbian monitoring campaign performed to assess the occupational exposure of petrochemical industry workers to benzene (B), toluene (T), ethylbenzene (E), and xylene (X), known collectively as BTEX. The following urinary biomarkers were investigated: phenol, hippuric acid, o-Cresol, p-Cresol, and creatinine. BTEX compounds were collected in 2014 using Casella passive samplers. Multivariate statistical analysis was performed to put in evidence the correlation between the BTEX measured in air and the concentration of urinary biomarkers. While the results indicate an elevated presence of benzene in the air in the working environment studied that surpasses the national and European Occupational Exposure Limits (OEL), the levels of the remaining (TEX) parameters measured were below the OEL. The high relative standard deviations (RSD) for the concentrations of each BTEX compound (68–161 mg m−3) point toward an intensive occupational exposure to BTEX. This was confirmed by relevant urine biomarkers, particularly by the mean values of phenol, which were ten and fourteen times higher than the ones found in the control group (14–12 mg g−1 of creatinine). On average, workers are at a higher risk of developing cancer (6.1 × 10−3), with risk levels exceeding the US EPA limits. Benzene levels should therefore be maintained under tight controls and monitored via proper urinary biomarkers.


Author(s):  
Sen Zhang ◽  
Dingxi Wang ◽  
Yi Li ◽  
Hangkong Wu ◽  
Xiuquan Huang

Abstract The time spectral method is a very popular reduced order frequency method for analyzing unsteady flow due to its advantage of being easily extended from an existing steady flow solver. Condition number of the inverse Fourier transform matrix used in the method can affect the solution convergence and stability of the time spectral equation system. This paper aims at evaluating the effect of the condition number of the inverse Fourier transform matrix on the solution stability and convergence of the time spectral method from two aspects. The first aspect is to assess the impact of condition number using a matrix stability analysis based upon the time spectral form of the scalar advection equation. The relationship between the maximum allowable Courant number and the condition number will be derived. Different time instant groups which lead to the same condition number are also considered. Three numerical discretization schemes are provided for the stability analysis. The second aspect is to assess the impact of condition number for real life applications. Two case studies will be provided: one is a flutter case, NASA rotor 67, and the other is a blade row interaction case, NASA stage 35. A series of numerical analyses will be performed for each case using different time instant groups corresponding to different condition numbers. The conclusion drawn from the two real life case studies will corroborate the relationship derived from the matrix stability analysis.


Author(s):  
Yeansu Kim ◽  
Loren Spice ◽  
Sandeep Varma

Abstract Let ${\text G}$ be a reductive group over a $p$-adic field $F$ of characteristic zero, with $p \gg 0$, and let $G={\text G}(F)$. In [ 15], J.-L. Kim studied an equivalence relation called weak associativity on the set of unrefined minimal $K$-types for ${\text G}$ in the sense of A. Moy and G. Prasad. Following [ 15], we attach to the set $\overline{\mathfrak{s}}$ of good $K$-types in a weak associate class of positive-depth unrefined minimal $K$-types a ${G}$-invariant open and closed subset $\mathfrak{g}_{\overline{\mathfrak{s}}}$ of the Lie algebra $\mathfrak{g} = {\operatorname{Lie}}({\text G})(F)$, and a subset $\tilde{{G}}_{\overline{\mathfrak{s}}}$ of the admissible dual $\tilde{{G}}$ of ${G}$ consisting of those representations containing an unrefined minimal $K$-type that belongs to $\overline{\mathfrak{s}}$. Then $\tilde{{G}}_{\overline{\mathfrak{s}}}$ is the union of finitely many Bernstein components of ${G}$, so that we can consider the Bernstein projector $E_{\overline{\mathfrak{s}}}$ that it determines. We show that $E_{\overline{\mathfrak{s}}}$ vanishes outside the Moy–Prasad ${G}$-domain ${G}_r \subset{G}$, and reformulate a result of Kim as saying that the restriction of $E_{\overline{\mathfrak{s}}}$ to ${G}_r\,$, pushed forward via the logarithm to the Moy–Prasad ${G}$-domain $\mathfrak{g}_r \subset \mathfrak{g}$, agrees on $\mathfrak{g}_r$ with the inverse Fourier transform of the characteristic function of $\mathfrak{g}_{\overline{\mathfrak{s}}}$. This is a variant of one of the descriptions given by R. Bezrukavnikov, D. Kazhdan, and Y. Varshavsky in [8] for the depth-$r$ Bernstein projector.


2021 ◽  
Vol 7 ◽  
pp. 327-343
Author(s):  
Stjepan Kvesić ◽  
Mirzeta Memišević Hodžić ◽  
Matijaž Čater ◽  
Dalibor Ballian

Morphologic variability from 25 populations of Acer campestre L. in Bosnia and Herzegovina was analyzed. Morphometric structure of variability and between-population variability was performed based on 10 fruit-parameter characteristics and 19 leaf-parameter characteristics using multivariate statistical analysis. Results confirmed the separation of three submediterranean populations as a group in relation to other tested populations, from which the Banja Luka population is different. Measured leaf parameters were confirmed as a predominant carrier of the morphologic separation between populations. In other Acer species populations within A. monspessulanum and A. intermedium species are separated mainly by fruit and much less by leaf parameters. The southernmost submediterranean populations from Trebinje, Ljubu&scaron;ki, and Mostar regions have smaller leaf areas, which consequently places them within the same morphologic group; their variability is in tight connection with eco-geo-graphical factors, where the ecological distance is a much better predictor of morphological variability compared to geographical distance. The air temperature had the biggest influence on morphological variability regarding the highest in-between correlation. Achieved results may serve for the continuation of the research in other areas of Acer campestre to determine the interactive effect of ecological, geographical, climatic, and migrational factors on their morphologic population plasticity.


Author(s):  
Alireza Jamali

After proposing a natural metric for the space in which particles spin which implements the principle of maximum frequency, E=hf is generalised and its inverse Fourier transform is calculated.


2021 ◽  
Author(s):  
Danrlei Menezes ◽  
Masato Kobiyama

&lt;p&gt;The aim of the present study was to characterize the size and shape of sediments along a reach of a mountain river in Maquin&amp;#233; municipality, southern Brazil, to establish an efficient methodology in river sediments analysis. In Brazil, this might be a pioneering study of mountain rivers characterized by the presence of gravel, cobble, and boulders sediments. The study catchment, covered by Dense and Mixed Rain Forest and high-altitude grasslands (Campos de Cima da Serra), has an altitude difference of 900 m. Its geology is characterized by the Serra Geral Formation (basaltic rocks) and pedology by Cambisols and Neossols. The mean annual rainfall is 1200 mm. According to the K&amp;#246;ppen classification, the regional climate is humid subtropical with hot summers (Cfa) in lower areas and humid subtropical with mild summers and cold winters (Cfb) in higher areas. The catchment outlet has a fluviometric station, and at its headwater, there is a rainfall gauge, both of which perform automatic measurements every 10 min. For the bed sediments diameter analysis, 500 grains were sampled, following the Wolman Pebble Count methodology. The measurements were carried out along the same reach (100 m) in five stages (December 2019; February, May, August, and November 2020) to observe sediment dynamics over time. During these measurements, the mean values of water depth and discharge were 0.4 m and 0.8 m&amp;#179;/s, respectively. To determine the size and shape, the three axes A (longest), B (intermediate), and C (shortest) were measured by using the tree caliper. With the axes&amp;#8217; values, the sediment shape was classified into four types: sphere, rod, disc, and blade. Linear correlation and multiple regression analyses were performed to evaluate the influence of each sediment axis on determining the nominal diameter (D&lt;sub&gt;n&lt;/sub&gt;). The mean values of D&lt;sub&gt;max&lt;/sub&gt;, D&lt;sub&gt;90&lt;/sub&gt;, D&lt;sub&gt;84&lt;/sub&gt;, D&lt;sub&gt;50&lt;/sub&gt;, D&lt;sub&gt;16,&lt;/sub&gt; and D&lt;sub&gt;10&lt;/sub&gt; of all the sampled sediments were 290.61, 114.40, 103.52, 56.27, 35.89, 28.0, and 18.40, respectively. Preliminary results indicate that 38% of the sampled sediments corresponded to the disc format and did not vary over the year. The characteristic diameters remained constant throughout the monitoring period, even though strong rainfall-runoff events sometimes occurred (~ maximum runoff was 33 m&amp;#178;/s in July 2020). The D&lt;sub&gt;n&lt;/sub&gt; values calculated with the multiple regression model based on the analysis of the axes (D&lt;sub&gt;n&lt;/sub&gt; = f (A, B, f (A, B))) were very close (R&amp;#178; = 0.95) to those calculated through an original definition of D&lt;sub&gt;n&lt;/sub&gt;, i.e., D&lt;sub&gt;n&lt;/sub&gt; = (A&amp;#183;B&amp;#183;C)&lt;sup&gt;1/3&lt;/sup&gt;. During the monitoring period, notable changes in the size and shape of the sediments were not observed. The axes analysis confirms that the D&lt;sub&gt;n&lt;/sub&gt; value can be estimated only with the measurement of axes A and B, without axis C. Therefore, this methodology (without the axis C) may be recommended to characterize the size and shape of bed sediments in mountain rivers. Finally, the present study highlights the importance of fieldwork to advance basic river sciences in Brazil.&lt;/p&gt;


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