scholarly journals A new method for quantifying heterochrony in evolutionary lineages

Paleobiology ◽  
2020 ◽  
pp. 1-22 ◽  
Author(s):  
James C. Lamsdell
Keyword(s):  
Environmental Gradients ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Environmental Pressures ◽  
Primary Mechanism ◽  
Phylogenetic Framework ◽  
Morphological Variants ◽  
Organismal Development ◽  
Internal Relationships ◽  
Evolutionary Lineages

Abstract The occupation of new environments by evolutionary lineages is frequently associated with morphological changes. This covariation of ecotype and phenotype is expected due to the process of natural selection, whereby environmental pressures lead to the proliferation of morphological variants that are a better fit for the prevailing abiotic conditions. One primary mechanism by which phenotypic variants are known to arise is through changes in the timing or duration of organismal development resulting in alterations to adult morphology, a process known as heterochrony. While numerous studies have demonstrated heterochronic trends in association with environmental gradients, few have done so within a phylogenetic context. Understanding species interrelationships is necessary to determine whether morphological change is due to heterochronic processes; however, research is hampered by the lack of a quantitative metric with which to assess the degree of heterochronic traits expressed within and among species. Here I present a new metric for quantifying heterochronic change, expressed as a heterochronic weighting, and apply it to xiphosuran chelicerates within a phylogenetic context to reveal concerted independent heterochronic trends. These trends correlate with shifts in environmental occupation from marine to nonmarine habitats, resulting in a macroevolutionary ratchet. Critically, the distribution of heterochronic weightings among species shows evidence of being influenced by both historical, phylogenetic processes and external ecological pressures. Heterochronic weighting proves to be an effective method to quantify heterochronic trends within a phylogenetic framework and is readily applicable to any group of organisms that have well-defined morphological characteristics, ontogenetic information, and resolved internal relationships.

scholarly journals The evolutionary assembly of forest communities along environmental gradients: recent diversification or sorting of pre-adapted clades?

2020 ◽  
Author(s):  
Alexander G. Linan ◽  
Jonathan A. Myers ◽  
Christine E. Edwards ◽  
Amy E. Zanne ◽  
Stephen A. Smith ◽  
...  
Keyword(s):  
Environmental Gradients ◽  
Elevational Gradient ◽  
Relative Importance ◽  
Evolutionary Processes ◽  
Peruvian Andes ◽  
Adaptive Diversification ◽  
Primary Mechanism ◽  
Tree Communities ◽  
Phylogenetic Framework ◽  
Ecological Sorting

AbstractHistorical biogeographic events such as mountain orogeny are associated with the creation of environmental gradients, giving rise to the assembly of communities of species observed today. However, key gaps remain in our understanding of the relative importance of different eco-evolutionary processes acting as drivers of community assembly across environmental gradients. In this study, we test two non-exclusive hypotheses of the eco-evolutionary processes that shape tree communities across the Central Andean elevational gradient: Communities are assembled via 1) immigration and ecological sorting of pre-adapted clades, and 2) recent adaptive diversification along the elevational gradient. We used species surveys in the Bolivian and Peruvian Andes and a novel phylogenetic framework to test the relative importance of these hypotheses. Although adaptive diversification has previously been observed in specific clades, immigration and sorting of clades pre-adapted to montane habitats is the primary mechanism shaping communities across elevations.

Characteristics of the course of nephritis associated with Iga-vasculitis Henoch-Schoenlein in children

2020 ◽  
Vol 24 (3) ◽  
pp. 64-71
Author(s):  
A. V. Sukalo ◽  
I. A. Kazyra
Keyword(s):  
Clinical Laboratory ◽  
Morphological Changes ◽  
Pediatric Nephrology ◽  
Morphological Characteristics ◽  
Lymphocyte Activation ◽  
Renal Tissue ◽  
Kidney Damage ◽  
Iga Vasculitis ◽  
Factors Affecting ◽  
Treatment Regimens

INTRODUCTION. Among systemic vasopathies in children, IgA vasculitis Henoch Schoenlein (HS) is the most common, according to various authors, kidney damage is noted in 25-80 % and usually determines the prognosis of the disease.THE AIM of the study was to analyze clinical, laboratory, immunological, morphological characteristics, features of the course and treatment of nephritis associated with IgA vasculitis HS in children, as well as factors affecting the prognosis.PATIENTS AND METHODS. The study included 31 patients with morphologically verified nephritis due to IgA vasculitis HS (18 – boys, 13 – girls) aged 3 to 17 years, who were monitored at the Nephrology Department of the "2nd Children's City Clinical Hospital" of the National Center for Pediatric Nephrology and Renal Replacement therapy in Minsk from 2010 to 2019 yrs.The following parameters were analyzed: the clinical variant of kidney damage, laboratory tests (including the study of BAFF, RANTES lymphocyte activation molecules, pro-inflammatory IL1β, caspase1, TNFα, growth factors VEGF, TGF), 24 hours monitoring and office blood pressure measurements, ECHO cardiography with indicescalculation, ultrasound of the carotid arteries with the thickness of intima-media complex, morphological changes in the renal tissue, as well as treatment regimens.RESULTS. The contribution of deGal-IgA1, markers of T and B lymphocytes activation, pro-inflammatory and profibrotic molecules in the development of the disease is shown. Arterial hypertension was registered in 42 % of children, signs of heart remodeling according to the calculated indices in 19,3 %. Decrease level of adiponectin, vitamin D, leptin, increase concentration of obestatin, Pro-BNP, hs-CRP, and TSAT indicator classify patients with nephritis due to IgA vasculitis HS at moderate risk for the developmentof cardio-vascular disorders, which suggests the need for timely correction.CONCLUSION. In most cases, nephritis with IgA vasculitis HS has a benign course with rare relapses and progression to the end stage of chronic kidney disease (6,5 %).

scholarly journals Myxomatous Mitral Valve Disease with Mitral Valve Prolapse and Mitral Annular Disjunction: Clinical and Functional Significance of the Coincidence

2021 ◽  
Vol 8 (2) ◽  
pp. 9
Author(s):  
Nina C. Wunderlich ◽  
Siew Yen Ho ◽  
Nir Flint ◽  
Robert J. Siegel
Keyword(s):  
Mitral Valve ◽  
Mitral Valve Disease ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Mitral Annulus ◽  
Ventricular Myocardium ◽  
Left Ventricular ◽  
Valve Disease ◽  
Left Ventricular Myocardium ◽  
Basal Portion

The morphological changes that occur in myxomatous mitral valve disease (MMVD) involve various components, ultimately leading to the impairment of mitral valve (MV) function. In this context, intrinsic mitral annular abnormalities are increasingly recognized, such as a mitral annular disjunction (MAD), a specific anatomical abnormality whereby there is a distinct separation between the mitral annulus and the left atrial wall and the basal portion of the posterolateral left ventricular myocardium. In recent years, several studies have suggested that MAD contributes to myxomatous degeneration of the mitral leaflets, and there is growing evidence that MAD is associated with ventricular arrhythmias and sudden cardiac death. In this review, the morphological characteristics of MAD and imaging tools for diagnosis will be described, and the clinical and functional aspects of the coincidence of MAD and myxomatous MVP will be discussed.

REACTION OF CD68-POSITIVE RAT LIVER AND SPLEEN CELLS ON SILICON INTAKE WITH DRINKING WATER

2021 ◽  
pp. 34-43
Author(s):  
Evgeniia A. Grigoreva ◽  
Valentina S. Gordova ◽  
Valentina E. Sergeeva ◽  
Alina T. Smorodchenko
Keyword(s):  
Drinking Water ◽  
Cytoplasmic Membrane ◽  
Unit Area ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Control Group ◽  
Silicon Compound ◽  
Average Cell ◽  
Laboratory Rats ◽  
Experimental Group

The article presents data on the long-term effect (nine months) of a silicon compound supplied with drinking water – nonahydrate sodium metasilicate (10 mg/l in terms of silicon), on CD68-positive macrophages in the liver and spleen of laboratory rats. Changes in the morphological characteristics of this cell population were found. There was a decrease in the average cell area (in the liver of the control group of rats, the average macrophage area was 179.23±5.94 microns2, and in the group receiving silicon with drinking water – 117.04±3.35 microns2; in the spleen-136.02±3.93 microns2 and 103.44±2.8 microns2, respectively). Macrophages in the liver preparations of the experimental group of rats had a fewer processes and a darker cytoplasmic membrane. The number of macrophages in the liver per unit area was comparable, for the control group of rats it was 18.78±1.24, and for the rats that received with water with the addition of silicon – 19.41±0.75 cells. CD68+ macrophages of the red splenic pulp in laboratory rats that received silicon also underwent the following morphological changes: they were located in a denser way and had fewer processes, while the number of macrophages per unit area was 73.7±2.3 for the control group, 91.6±5.0-for the experimental group, respectively. The distance between them did not change. There was a change in the intensity of CD68 expression on the surface of the cytoplasmic membrane and in the cytoplasm of liver and spleen macrophages. These changes can be interpreted as the adaptive ability of liver and spleen macrophages to silicon introduced with drinking water. Given the heterogeneity of the macrophage population in the liver and spleen, further studies using markers for different subpopulations of macrophages are needed to clarify their role in the response of tissues to silicon supplied with drinking water.

Cryptic diversity in the smooth snake (Coronella austriaca)

2019 ◽  
Vol 40 (2) ◽  
pp. 179-192 ◽  
Author(s):  
Daniel Jablonski ◽  
Zoltán T. Nagy ◽  
Aziz Avcı ◽  
Kurtuluş Olgun ◽  
Oleg V. Kukushkin ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Dna Sequences ◽  
Integrative Approach ◽  
Biogeographic Pattern ◽  
Western Palearctic ◽  
The Rich ◽  
Morphological Variants ◽  
Glacial Periods ◽  
Coronella Austriaca ◽  
Evolutionary Lineages

Abstract The smooth snake, Coronella austriaca, is a common snake species widespread in the Western Palearctic region. It does not form conspicuous morphological variants and, although several evolutionary lineages have been distinguished based on the analyses of the mitochondrial DNA sequences, only two subspecies with very limited distribution have been traditionally recognized. Here we present an mtDNA phylogeography of the species using geographically extended sampling while incorporating biogeographically important areas that have not been analyzed before, such as Anatolia, Crimea, and Iran. We find that the smooth snake comprises 14 distinct phylogenetic clades with unclear mutual relationships, characterized by complex genetic structure and relatively deep divergences; some of them presumably of Miocene origin. In general, the biogeographic pattern is similar to other Western Palearctic reptiles and illustrates the importance of the main European peninsulas as well as the Anatolian mountains, Caucasus, and Alborz Mts. in Iran for the evolution of the present-day diversity. Considerable genetic structure present in the smooth snake populations within these large areas indicates the existence of several regional Plio-Pleistocene refugia that served as reservoirs for dispersal and population expansions after the glacial periods. The current taxonomy of C. austriaca does not reflect the rich genetic diversity, deep divergences, and overall evolutionary history revealed in our study and requires a thorough revision. This will only be possible with an even higher-resolution sampling and integrative approach, combining analyses of multiple genetic loci with morphology, and possibly other aspects of the smooth snake biology.

scholarly journals Spatiotemporal Patterns and Morphological Characteristics of Ulva prolifera Distribution in the Yellow Sea, China in 2016–2018

2019 ◽  
Vol 11 (4) ◽  
pp. 445 ◽  
Author(s):  
Yingzhi Cao ◽  
Yichen Wu ◽  
Zhixiang Fang ◽  
Xiaojian Cui ◽  
Jianfeng Liang ◽  
...  
Keyword(s):  
Yellow Sea ◽  
Vegetation Index ◽  
Morphological Changes ◽  
Surface Wind ◽  
Morphological Characteristics ◽  
Ulva Prolifera ◽  
Spatiotemporal Patterns ◽  
The Yellow Sea ◽  
Green Tide ◽  
Sea Surface Wind

The world’s largest macroalgal blooms, Ulva prolifera, have appeared in the Yellow Sea every summer on different scales since 2007, causing great harm to the regional marine economy. In this study, the Normalized Difference of Vegetation Index (NDVI) index was used to extract the green tide of Ulva prolifera from MODIS images in the Yellow Sea in 2016–2018, to investigate its spatiotemporal patterns and to calculate its occurrence probability. Using the standard deviational ellipse (SDE), the morphological characteristics of the green tide, including directionality and regularity, were analyzed. The results showed that the largest distribution and coverage areas occurred in 2016, with 57,384 km2 and 2906 km2, respectively and that the total affected region during three years was 163,162 km2. The green tide drifted northward and died out near Qingdao, Shandong Province, which was found to be a high-risk region. The coast of Jiangsu Province was believed to be the source of Ulva prolifera, but it was probably not the only one. The regularity of the boundary shape of the distribution showed a change that was opposite to the variation of scale. Several sharp increases were found in the parameters of the SDE in all three years. In conclusion, the overall situation of Ulva prolifera was still severe in recent years, and the sea area near Qingdao became the worst hit area of the green tide event. It was also shown that the sea surface wind played an important part in its migration and morphological changes.

Stent-Graft Migration following Endovascular Repair of Aneurysms with Large Proximal Necks: Anatomical Risk Factors and Long-term Sequelae

2002 ◽  
Vol 9 (5) ◽  
pp. 652-664 ◽  
Author(s):  
James T. Lee ◽  
Jason Lee ◽  
Ihab Aziz ◽  
Carlos E. Donayre ◽  
Irwin Walot ◽  
...  
Keyword(s):  
Stent Graft ◽  
Endovascular Repair ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Anatomical Characteristic ◽  
Computed Tomographic ◽  
Aortic Neck ◽  
Distal Migration ◽  
Graft Migration ◽  
Over Time

Purpose: To evaluate the outcome of aortic endografts deployed in large infrarenal necks and to identify any association of preoperative aneurysm characteristics and postoperative morphological changes with the incidence of neck dilatation and device migration in this patient subset. Methods: The records of 47 patients (41 men; mean age 74, range 55–84) with large aortic neck diameters treated with Talent stent-grafts from 1998 to 2001 were reviewed. Patients with anatomical criteria that precluded aneurysm exclusion with currently available devices were preferentially selected. Mean baseline aneurysm morphology included 27.6-mm (range 18–33.4) suprarenal and 28.1-mm (range 24–34) infrarenal neck diameters; the infrarenal neck length was 26 ± 16 mm with angulation of 37° ± 18°. Computed tomographic (CT) angiograms up to 3 years were analyzed using specialized interactive software; migration was defined as >1-cm change in the distance from the lower renal artery to the top of the device. Pre- and postoperative morphological characteristics of the aneurysm were compared between patients with and without migration. Results: Of the 45 patients successfully treated, 40 had complete CT data for analysis. During a mean 17-month follow-up, 7 (17.5%) of the 40 devices exhibited distal migration. Six patients required secondary procedures; 5 were in the migration cohort. No preoperative anatomical characteristic or degree of neck dilatation over time was predictive of stent-graft migration. Aneurysm sac regression was significant at 1 (–0.09 ± 4.90 mm) and 2 (–1.48 ± 2.56 mm) years in endografts without migration (p<0.001). Distal endograft migration >1 cm predicted the need for secondary interventions (p<0.001), with 83% sensitivity and 94% specificity. Conclusions: Endovascular repair is successful in patients with large infrarenal necks and complex neck morphology. Changes in aneurysm remodeling over time were similar to reported observations in patients with more favorable neck criteria. Although no anatomical factor associated with migration could be identified from this analysis, distal displacement >1 cm correlated with the need for a secondary intervention.

Predictors of rapid plaque progression: an optical coherence tomography study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Araki ◽  
T Yonetsu ◽  
O Kurihara ◽  
A Nakajima ◽  
H Lee ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Multivariable Analysis ◽  
Morphological Characteristics ◽  
Critical Threshold ◽  
Rapid Progression ◽  
Plaque Progression ◽  
Plaque Disruption ◽  
Lipid Rich Plaque ◽  
Oct Imaging

Abstract Background Two patterns of plaque progression have been described: slow linear progression and rapid step-wise progression. The former will cause stable angina when the narrowing reaches a critical threshold, while the latter may lead to acute coronary syndromes or sudden cardiac death. Purpose The aim of the study was to identify morphologic predictors for rapid plaque progression. Methods Patients who had OCT imaging during the index procedure and follow-up angiography with a minimum of 6-month interval were selected. Non-culprit lesion was defined as a plaque with a diameter stenosis ≥30% on index angiogram. Lesion progression was defined as the decrease of angiographic minimum lumen diameter ≥0.4 mm at follow-up (mean, 7.1 months). Baseline morphological characteristics of the plaques with rapid progression were evaluated by OCT. In a subgroup with follow-up OCT imaging for plaques with progression, morphological changes from baseline to follow-up were assessed. Results Among 517 lesions, 50 lesions showed progression. These lesions had a significantly higher prevalence of lipid-rich plaque (76.0% vs. 50.5%), thin-cap fibroatheroma (TCFA) (20.0% vs. 5.8%), layered plaque (60.0% vs. 34.0%), macrophage accumulation (62.0% vs. 42.4%), microvessel (46.0% vs. 29.1%), plaque rupture (12.0% vs. 4.7%), and thrombus (6.0% vs. 1.1%), compared to those without progression. The multivariable analysis identified lipid-rich plaque [odds ratio (OR) 2.17, 95% confidence interval (CI) 1.02–4.62, p=0.045], TCFA (OR 5.85, 95% CI 2.01–17.03, p=0.001), and layered plaque (OR 2.19, 95% CI 1.03–4.17, p=0.040) as predictors of subsequent lesion progression. In a subgroup with follow-up OCT, a new layer was detected in 14/41 (34.1%) plaques. Conclusions Lipid-rich plaque, TCFA, and layered plaque were predictors of subsequent rapid plaque progression. A new layer, a signature of rapid progression through plaque disruption and healing, was detected in 1/3 of the cases. Funding Acknowledgement Type of funding source: None

scholarly journals Morphological characteristics of soybean root apexes as indicators of soil compaction

2010 ◽  
Vol 67 (6) ◽  
pp. 707-712 ◽  
Author(s):  
Julio César Ramos ◽  
Silvia Del Carmen Imhoff ◽  
Miguel Ángel Pilatti ◽  
Abelardo Carlos Vegetti
Keyword(s):  
Form Factor ◽  
Soil Compaction ◽  
Morphological Changes ◽  
Root Hairs ◽  
Morphological Characteristics ◽  
Mechanical Impedance ◽  
Soil Bulk Density ◽  
Root Diameter ◽  
Secondary Root ◽  
Plant Soil

Plant soil compaction poses a serious problem to agriculture because it produces different types of changes in plant characteristics. No method has been implemented to date to use root morphological changes as indicators of soil compaction levels. Therefore, the aim of the present study was to evaluate whether or not the morphological changes in root apexes of soybean (Glycine max (L.) Merrill) can be used as indicators of soil compaction levels. To this end, a silt-loamy soil material (from a Typic Argiudoll, Esperanza series), sieved through a 2 mm mesh was used and the following soil bulk density levels were determined: 1.1, 1.3 and 1.5 g cm³ for which the corresponding mechanical resistances were < 0.1, 0.5 and 3.5 MPa, respectively. The distance from the apex to the first tertiary root and the root diameter at 1.5 cm from the apex were measured on the secondary root apexes. A form factor equal to the quotient between these two variables was subsequently calculated. An inverse relationship between soil mechanical impedance and secondary root length and form factor as well as a direct relationship with the secondary root diameter were observed. Changes in rhizodermis cells were also recorded. The following morphological characteristics were found to evidence the highest sensitivity to soil compaction: i) the form factor, ii) rhizodermis papillose cells, iii) apical malformations in root hairs, and iv) root diameter in expansion areas. Taken together, the morphological characteristics of root apexes could be considered to be indicative of soil compaction.

Study on the Plant Protection Effect of Highway Slope

2012 ◽  
Vol 430-432 ◽  
pp. 1573-1576
Author(s):  
Qing Wu ◽  
Yuee Chen ◽  
Lu Zhang
Keyword(s):  
Plant Protection ◽  
Morphological Changes ◽  
Morphological Characteristics ◽  
Site Conditions ◽  
Average Width ◽  
Protection Effect ◽  
Loess Slope ◽  
Design Program ◽  
Plant Configuration ◽  
Heavy Rains

In order to verify the effect of plant protection design program of a highway slope in the western of Henan, the artificial simulating rainfall and runoff scouring test were carried out. The results showed that, under the condition of design frequency heavy rains, if the site conditions and the measures of plant configuration were different, the morphological characteristics of slope erosion were different too. There were some difference among the size, quantity and morphological changes of slope erosion gully. The rill width and depth of brown loess slope was biggest, and the bill average width and depth had a significant relationship with its length.

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