Morphological Changes

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Morphological changes in the corpus callosum: A study using a joint Riemannian feature spaces

Morphological changes in the corpus callosum: A study using a joint Riemannian feature spaces

concentration of white matter tracts and we expect it to be disproportionately affected. The study of morphological changes in the CC, which falls under the purview of shape analysis, can be categorized as volume-based or tract-based. With volume-based analysis, two broad approaches have been followed in the literature. The first approach has been to present the CC as an abstraction using a geometric representation such as a fixed topology skeleton or a medial axis description. Classification using a linear discriminant method such as support vector machine (SVM) is then performed. 11, 12 In other studies, different
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Morphological changes in the spiracles of Anopheles gambiae s.l (Diptera) as a response to the dry season conditions in Burkina Faso (West Africa)

Morphological changes in the spiracles of Anopheles gambiae s.l (Diptera) as a response to the dry season conditions in Burkina Faso (West Africa)

Wadaka Mamai 1,2,3,7* , Karine Mouline 1,2 , Jean-Philippe Parvy 4,5 , Jo Le Lannic 6 , Kounbobr Roch Dabiré 1 , Georges Anicet Ouédraogo 3 , David Renault 6 and Frederic Simard 2 Abstract Background: Survival to dry season conditions of sub-Saharan savannahs is a major challenge for insects inhabiting such environments, especially regarding the desiccation threat they are exposed to. While extensive literature about insect seasonality has revealed morphologic, metabolic and physiological changes in many species, only a few studies have explored the responses following exposure to the stressful dry season conditions in major malaria vectors. Here, we explored morphological changes triggered by exposure to dry season conditions in An. gambiae s.l. mosquitoes by comparing females reared in climatic chambers reflecting environmental conditions found in mosquito habitats during the rainy and dry seasons in a savannah area of Burkina Faso (West Africa).
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A model of brain morphological changes related to aging and Alzheimer's disease from cross-sectional assessments

A model of brain morphological changes related to aging and Alzheimer's disease from cross-sectional assessments

prodromal stages. Third, we show that the markers and the generative model can be used in a personal- ized image simulation setting. It allows us to generate smooth and realistic evolutions for several diagnosis conditions. Biological (or here morphological) age estimates were proven to be interesting to analyze the patient condition; here, in addition, the disease score is used to get a simple marker of the disease progression. The joint modeling gives a more complete description of the disease progression than a brain-age metric. The evolution is not seen as a simple accelerated aging process or the divergence from the normal evolution. On the contrary, it seems possible to capture the general worsening with the morphological age while the disease score measures an additional evolution that is more specific to the disease. Both patterns of evolution appeared to be related with the development of Alzheimer’s disease and this approach provides an intuitive interpretation and a simple decomposition of the morphological changes observed in mass-univariate mor- phometric approaches. Further analysis should be conducted to analyze the relation of these complementary patterns to clinical and cognitive variables.
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Long-term morphological changes and evolving human-pig relations in the northern Fertile Crescent from 11,000 to 2000 cal. bc

Long-term morphological changes and evolving human-pig relations in the northern Fertile Crescent from 11,000 to 2000 cal. bc

Title: Long-Term Morphological Changes and Evolving Human-Pig Relations in the Northern Fertile Crescent from 11,000-2000 cal. BC Abstract: The pig (Sus scrofa) was one of the earliest animals in the ancient Middle East to un- dergo domestication. Scholars have long been interested in the pig’s unique history, especially in the northern Fertile Crescent (NFC), the region in which the first steps towards pig domestication took place in the 9 th -8 th millennia cal. BC. Yet, few zooarchaeologists have studied the morpho- logical changes in pigs and other animals over the long term, especially in the periods after the initial appearance of domesticates. We combine Geometric Morphometrics (GMM) and more traditional biometrics to demonstrate how suid morphology evolved over a long timespan: 11,000-2000 cal. BC. Our GMM and biometrical data from Jarmo and Domuztepe, Neolithic sites occupied after the first domestic pigs emerged in the region, show that wild boar continued to play important roles in human-suid relations. More generally, our data show a gradual reduc- tion in size and the attainment of a “morphological plateau” in the 4 th millennium cal. BC. We suggest that these changes reflect 1) the evolution of pig husbandry practices over time in re- sponse to deforestation, intensive agriculture, and urbanism; and 2) a reduction in the frequency of hybridizations between wild boar and domestic pigs.
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Statistical Characterization, Modelling and Classification of Morphological Changes in imp Mutant Drosophila Gamma Neurons

Statistical Characterization, Modelling and Classification of Morphological Changes in imp Mutant Drosophila Gamma Neurons

3 Institute of Biology Valrose, University of Nice Sophia Antipolis, Parc Valrose, Nice, France arazetti@unice.fr, xavier.descombes@inria.fr , {caroline.medioni, florence.besse}@unice.fr Keywords: Gamma neurons, Remodelling, Stochastic models, Likelihood analysis. Abstract: In Drosophila brain, gamma neurons in the mushroom body are involved in higher functions such as olfactory learning and memory. During metamorphosis, they undergo remodelling after which they adopt their adult shape. Some mutations alter remodelling and therefore neuronal final morphology, causing behavioural dysfunctions. The RNA binding protein Imp, for example, was shown to control this remodelling process at least partly by regulating profilin expression. This work aims at precisely characterizing the morphological changes observed upon imp knockdown in order to further understand the role of this protein. We develop a methodological framework that consists in the selection of relevant morphological features, their modelling and parameter estimation. We thus perform a statistical comparison and a likelihood analysis to quantify similarities and differences between wild type and mutated neurons. We show that imp mutant neurons can be classified into two phenotypic groups (called Imp L and Imp Sh) that differ in several morphological aspects. We also demonstrate that, although Imp L and wild-type neurons show similarities, branch length distribution is discriminant between these populations. Finally, we study biological samples in which Profilin was reintroduced in imp mutant neurons, and show that defects in main axon and branch lengths are partially suppressed.
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Response of Vicia faba L. to metal toxicity on mine tailing substrate:Geochemical and morphological changes in leaf and root

Response of Vicia faba L. to metal toxicity on mine tailing substrate:Geochemical and morphological changes in leaf and root

Moreover, on mine tailing substrate, the very high metal and calcium content led to significant ultrastructural changes in plant cells compared to soil. On soils, where translocation was favoured, dense particles of metals were stored in the cell walls. This sug- gests a mechanism of plant defence without cell ultrastructure alteration, within a certain critical limit of metal concentration in substrate. On mine tailings, where metal concentration limits were exceeded, plant growth was reduced by 38% and the cell walls were thickened in roots to limit metal absorption, whereas Pb- and Zn- enriched particles have entered the root damaged cells. In response to high concentrations of toxic metal, phytochelators Pb-complexes might be synthesized in root cells and control metal transport to stems and leaves. Moreover ultrastructure of leaf cells of plants growing on mine tailings was altered particularly for chloroplast and plastogobuli in relation to metal stress. Finally, concretions as Ca–P needle-like crystals close to apatite found in intercellular spaces and at the surface of the cell wall, were identified as another important regulatory mechanism. Zn was detected in those min- eral phases, whereas Pb could not be detected probably in relation to analytical detection limit. These crystals are supposed to be the ultimate phase of plant response to such highly exceeded metal and Ca content, before dying.
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An analysis of morphological changes in visual cortical neurons after knocking down scaffolding proteins of glutamate receptors

An analysis of morphological changes in visual cortical neurons after knocking down scaffolding proteins of glutamate receptors

We show that knocking down these proteins results in a decrease in soma size, an increase in the frequency of dendritic branching, and a reduction in the number of dendr[r]

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Vasopressin-induced morphological changes in polarized rat hepatocyte multiplets: Dual calcium-dependent effects.: calcium and polarized hepatocytes

Vasopressin-induced morphological changes in polarized rat hepatocyte multiplets: Dual calcium-dependent effects.: calcium and polarized hepatocytes

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignemen[r]

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A model of transient unilateral focal ischemia with reperfusion in the P7 neonatal rat: morphological changes indicative of apoptosis.

A model of transient unilateral focal ischemia with reperfusion in the P7 neonatal rat: morphological changes indicative of apoptosis.

Cell Death With the selective Gallyas silver staining, silver-impregnated cell bodies were seen in the cortex at 6 hours after ischemia (Figure 4A and 4B), and they increased with time of recir- culation. TUNEL labeling was detected in a few scattered cells of the sham-operated or control rat pup brains, which corresponds to the programmed cell death that occurs during development. In contrast, TUNEL-positive nuclei appeared as early as 4 hours of reperfusion in the frontoparietal cortex, increased up to 24 hours (Figure 4C and 4D and Figure 5), and remained stable until 96 hours (Figure 5). A progressive decrease in the number of apoptotic cells was observed from 7 to 30 days (Figure 5). The stained nuclei showed the morphological criteria of apoptosis, ie, cytoplasmic shrinkage and cytoplasmic membrane convolutions, chromatin conden- sation below the nuclear membrane, followed by fragmenta- tion of the nucleus into rounded or oval bodies (apoptotic bodies, Figure 4E through 4G). Necrotic cells, detected by diffused nuclear and cytoplasmic staining, 24
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Compositional and morphological changes for ordered PtxFey/C oxygen electroreduction catalysts

Compositional and morphological changes for ordered PtxFey/C oxygen electroreduction catalysts

surface area conversion factor of 210 μC cm -2 . This is the same factor as used by other research groups. [8] This is an estimate and does not take the possible interference of Fe into account. Transmission electron microscopy: The catalysts were characterized by ultrahigh-resolution transmission electron microscopy to extract morphological, size and composition information. High angle annular dark-field (HAADF) imaging and energy dispersive X-ray spectroscopy (EDXS) mapping were carried out using two aberration- corrected FEI Titan 80-300 microscopes operated at 200 keV. One of the instruments (FEI Titan 80-300 Cubed) is equipped with two aberration correctors (one of the probe-forming lens and one of the imaging lens) providing ultrahigh-resolution HAADF-STEM images (better than 0.1 nm resolution) and an EDXS detector (Oxford Instruments Si-Li detector). The other instrument is equipped with an aberration-corrector of the image-forming lens and an EDXS detector (Oxford Instruments Si-Li detector). Additional chemical compositional measurements were carried with a Tecnai Osiris microscope equipped with a high-collection efficiency FEI EDXS detector (ChemiSTEM system).
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Vascular and morphological changes of the optic nerve head following therapeutic intraocular pressure reduction in open angle glaucoma and ocular hypertension

Vascular and morphological changes of the optic nerve head following therapeutic intraocular pressure reduction in open angle glaucoma and ocular hypertension

Purpose: To compare optic nerve head (ONH) and peripapillary retinal blood flow in subjects with open angle glaucoma (OAG), ocular hypertension (OHT), and normal e[r]

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When European meets African honeybees (Apis mellifera L.) in the tropics: Morphological changes related to genetics in Mauritius Island (South-West Indian Ocean)

When European meets African honeybees (Apis mellifera L.) in the tropics: Morphological changes related to genetics in Mauritius Island (South-West Indian Ocean)

Results ). All the analyses mentioned above were conducted with the software MorphoJ ( https://www.R-project.org/ ) [ 54 ]. Congruence between morphological and neutral genetic variation To assess the congruence between morphometric and genetic datasets, we conducted partial least squares (PLS) analyses in MorphoJ using alternatively wings size and shape (i.e., centroid sizes and Procrustes coordinates) against microsatellite allele frequencies. The PLS method is based on a singular value decomposition of the matrix of covariances between two separate blocks of variables [ 55 , 56 ]. It resulted in paired axes uncorrelated and ordered by decreasing singular values, each forming linear combinations of the variables from each dataset and accounting for as much as possible of the overall covariance. The number of axes was equal to the number of dimensions in the smaller dataset (i.e. 1 for size and 34 for shape). The overall association between morphological and genetic datasets was assessed by the Escoufier’s RV coefficient [ 57 ], a multivariate generalization of the squared Pearson correlation coefficient ( r).
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Barrier properties of poly(lactic acid) and its morphological changes induced by aroma compound sorption

Barrier properties of poly(lactic acid) and its morphological changes induced by aroma compound sorption

However, to date, the link between barrier properties and crystallinity has been the subject of only a few studies. No data have been published on the influence of the sorption of volatile organic molecules, such as aroma compounds, in PLA on its morphological and thermomechanical properties, particularly the influence on the glass transition. From an application point of view, this knowledge will be helpful in the design of PLA with efficient barrier properties not only in food packaging applications. Therefore, in the study reported here, PLA samples with various crystallinities were prepared and studied. An industrial sample of PLA film (Biophan) was used as reference. For sample fabrication, the extrusion–thermocompression technique was preferred to the casting technique often used as a model process, in order to avoid a plasticizing effect due to the residual solvent which can affect the gas barrier properties. 20 Ethyl acetate was used as a
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Morphological triggers of syntactic changes: Treebank-based Information Theoretic approach

Morphological triggers of syntactic changes: Treebank-based Information Theoretic approach

2 Loss of morphological case and word order flexibility 2.1 Morphology-syntax tradeoff hypothesis Since both word order and morphological changes manifest themselves as gradual replacements of one alternative by another over the centuries rather than “overnight” categorical shifts, establishing a temporal relation between the two has been virtu- ally impossible until very recently due to the absence of tools for quantifying the relevant changes. Establishing the temporal profiles of the changes is, in turn, in- dispensable for modelling grammatical relations (if any) between the correspond- ing phenomena. These points seem to been overlooked in the debate about the relationship between case and word order, which led to claims such as the follow- ing one from [10, 22]: “a ... complication with the theory that phonetic attrition of the classical Latin case system necessitated a fixed Romance SVO order is that it is simply not true. ... [L]ate Latin and early Romance retained at least a bi- nary case system (nominative vs. oblique) and were characterized by Verb Second constraint, such that SVO was just one of many possible word orders. From this we can only conclude that there is no necessary causal relation between phonetic attrition, in this case acting upon the case system, and the emergence of analytic structural changes.” As we show below, such conclusions are unwarranted by the corpus data, given that the robustness of nominative marking, estimated based on the proportion of nominative marked subjects among all subjects, was different at different points in time (overall decreasing), and so was the robustness of linear position marking (overall increasing). 2 The mere fact that in a given text we find both nominative marked subjects and SVO orders does not necessarily speaks for or against a particular relation between case and order. In the following section we propose a way to track diachronic changes in the distribution of case markers and linear orders and to measure their contribution to the identification of syntactic
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Morphological and Functional Changes of Corneal Nerves and Their Contribution to Peripheral and Central Sensory Abnormalities

Morphological and Functional Changes of Corneal Nerves and Their Contribution to Peripheral and Central Sensory Abnormalities

Chronic pain induced after nerve injury is generally associated with prominent morphological and epigenetic changes within the afferent fibers. After nerve damage, destroyed peripheral nerves start to regenerate and form neuromas that exhibit abnormal responsiveness and spontaneous discharges (ectopic firing) ( Fawcett and Keynes, 1990 ). These functional changes are the consequence of altered expressions of ion channel proteins in the soma and in regenerating nerve terminals. Neuroma structures have emerged as other important morphological changes in corneal nerves and have been suggested as clinical imagining biomarkers (hallmark) of corneal neuropathic pain ( Aggarwal et al., 2019; Bayraktutar et al., 2020; Moein et al., 2020 ). Taken together, these studies suggest that a corneal neuroma may represent an important pathological feature of peripheral nerve abnormalities in patients with ocular pain. Interestingly, topical treatment with autologous serum tears reduced corneal nerve abnormalities, improved corneal nerve regeneration, and alleviated corneal pain ( Aggarwal et al., 2019 ). Future directions are needed to determine when and how the morphological changes occur on the ocular surface and which subpopulations of corneal neurons are hit.
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Anchors of morphological operators and algebraic openings

Anchors of morphological operators and algebraic openings

F IGURE 9. The profile of a function f and one of its threshold sets. In addition, there is a one-to-one correspondence between a function and families of sets X (t). In fact, the function f can be recovered from the series of X (t) by means of f (x) = W {t| x ∈ X(t)}; this is the threshold superposition principle. One interesting application of the correspondence is the possibility to interpret an opening on f as the union of B that fits in the threshold sets. From an implementation point of view, this leads to alternative definitions for morphological opera- tors. Although morphological openings were defined as the cascade of an erosion followed by a dilation [see Eq. ( 12 )], this does not mean that one must implement an opening according to its definition. Examples of the conclusion are, among others, the two implementations of an opening with a line proposed in Van Droogenbroeck (1994) and Vincent (1994). These implementations scans the image line by line and use threshold sets to compute the opening.
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Morphological probabilistic hierarchies for texture segmentation

Morphological probabilistic hierarchies for texture segmentation

3 Morphological texture descriptors We will consider images as domains D in the n dimensional space R n . Every pixel x is described by a set of morphological parameters or transformations building a vector with dimension p in the parameter space R p . For instance in the case of 2D multispectral images, we have n = 2 and p is the number of channels of each spectrum. Many types of transformations can be used. From experience, some standard families of morpho- logical transformations Ψ [21, 31], performed on an initial image, are efficient as texture descriptors [6, 7]: dilations δ ( ρ ), erosions ε ( ρ ), openings γ (r) or closings ϕ ( ρ ) by convex structuring elements with size ρ . These
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Morphological segmentation of hyperspectral images - ICSXII

Morphological segmentation of hyperspectral images - ICSXII

N OYEL G et al.: Morphological segmentation of hyperspectral images gradients are summed with a weight equal to one. After morphological filtering on the gradient, the local minima are used as markers for watershed segmentation. Scheunders (2001) computes a gradient by summation of channels gradients followed by a watershed segmentation. Soille (1996) combines spectral classification on histograms and spatial segmentation. The multidimensional histogram is segmented, using the watershed algorithm, to obtain a classified image. On the classified image the minima of the gradient of the hyperspectral image are imposed. With the gradient and the markers he applies the watershed segmentation.
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Eigenfunctions of Ultrametric Morphological Openings and Closings

Eigenfunctions of Ultrametric Morphological Openings and Closings

If one replaces the addition and multiplication of vectors and matrices by oper- ations of maximum and sum, the corresponding linear algebra is called max plus algebra, which has been extensively studied, including the eigenproblem, see for instance the book [11] for exhaustive list of references. But that prob- lem is out of the scope of this paper. Readers interested on maxplus matrix algebra and spectral analysis from the perspective of mathematical morphology are referred to the excellent survey by Maragos [13]. In the case where one re- places respectively by operations of maximum and minimum, we work on the so-called maxmin algebra (also known as bottleneck algebra [5]). Spectral anal- ysis in maxmin algebra is also relatively classic from their rst interpretation in the eld of hierarchical clustering [8]. Eigenvectors of max-min matrices and their connection with paths in digraphs were widely investigated by Gondran and Minoux, see overview papers [9,12], by Cechlárova [5] and by Gavalec [7]. Spectral analysis in maxmin algebras is also relatively classic in fuzzy reason- ing [15]. This eigenproblem in distributive lattice was studied in [16]. Procedures and ecient algorithms to compute the maximal eigenvector of a given max-min matrix has been also considered [5]. Max-min algebra is also very relevant in several morphological frameworks, such as fuzzy logic, viscous morphology or geodesic reconstruction, see our overview in [1].
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Image Characterization by Morphological Hierarchical Representations

Image Characterization by Morphological Hierarchical Representations

Secondly, one must choose the size of the considered patches in such approaches. Indeed, a sufficiently large patch size can widen the scope of analysis, thus enabling to be attentive to smoothly evolving brightness transitions, which is particularly useful when dealing with out-of-focus images. But if the patches are too large, thin homogeneous regions can be filled with high gradient values, which is not desirable for the detection of contours. In [Bricola et al. ( 2015 )], the authors derive from the regularized gradient [Rivest et al. ( 1992 )] a multi-scale morphological gradient that addresses both those issues. The main idea of the regularized gradient [Rivest et al. ( 1992 )] is to compute a morphological gradient at different scales and retains the highest gradient values across all scales, and then to thin the result using an erosion. In [Bricola et al. ( 2015 )], the authors propose enhancements to this technique: they avoid high gradient values in high frequencies images regions by filtering the input image beforehand, and replace the erosion step by a brightness transitions detection step. An example illustrating its effectiveness is provided in figure 3.36 .
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