scholarly journals Phenotypic variation in <i>Gyroidinoides altiformis</i> (Stewart & Stewart) and <i>Gyroidinoides subangulatus</i> (Plummer) (Foraminifera)

1991 ◽  
Vol 9 (2) ◽  
pp. 233-238 ◽  
Author(s):  
Roberto Barbieri
Keyword(s):  
Morphological Variation ◽  
Phenotypic Variation ◽  
Morphological Changes ◽  
Northern Italy ◽  
Foraminiferal Species ◽  
Late Neogene ◽  
Different Ages

Abstract. The morphological variation of two benthic foraminiferal species, Gyroidinoides altiformis (Stewart &amp; Stewart) and Gyroidinoides subangulatus (Plummer), are described from Late Neogene - Quaternary, and Palaeogene sequences from northern Italy and Greece. A number of morphotypes, two for each species, are thought to be ecophenotypes. The inferred ecological (bathymetric) conditioning derives from: 1) comparable shape variations occur in species of very different ages; 2) both species exhibit the same morphological changes as a result of a comparable environmental trend.

scholarly journals Rule Based Morphological Variation Removable Stemming Algorithm

2019 ◽  
Vol 8 (4) ◽  
pp. 1809-1814
Keyword(s):  
Feature Selection ◽  
Sentiment Analysis ◽  
Morphological Variation ◽  
Morphological Changes ◽  
The Internet ◽  
Rule Based ◽  
The People ◽  
Stop Word ◽  
Preprocessing Technique ◽  
Better Than

Sentiment analysis is a technique to analyze the people opinion, attitude, sentiment and emotion towards any particular object. Sentiment analysis has the following steps to predict the opinion of a review sentences. The steps are preprocessing, feature selection, classification and sentiment prediction. Preprocessing is the main important step and it consists of many techniques. They are Stop word Removal, punctuation removal, conversion of numbers to number names. Stemming is another important preprocessing technique which is used to transform the words in text into their grammatical root form and is mainly used to improve the retrieval of the information from the internet. It is applied mainly to get strengthen the retrieval of the information. Many morphological languages have immense amount of morphological deviation in the words. It triggered vast challenges. Many algorithms exist with different techniques and has several drawbacks. The aim of this paper is to propose a rule based stemmer that is a truncating stemmer. The new stemming mechanism in this paper has brought about many morphological changes. The new rule based morphological variation removable stemming algorithm is better than the existing other algorithms such as New Porter, Paice/Lovins and Lancaster stemming algorithm

scholarly journals Morphological changes of gastric and colonic mucosa in rats of different ages under the action of nanocrystalline cerium dioxide

2014 ◽  
Vol 68 (3) ◽  
pp. 46-50
Author(s):  
O. Iefimenko ◽  
O. Savchenko ◽  
T. Falalyeyeva ◽  
O. Kyric ◽  
M. Spivak
Keyword(s):  
Cerium Dioxide ◽  
Plasma Cells ◽  
Morphological Changes ◽  
Degenerative Changes ◽  
Control Group ◽  
Gastric Glands ◽  
Different Ages ◽  
Nanocrystalline Cerium Dioxide ◽  
Old Rats ◽  
Differentiation And Proliferation

We have studied the effect of nanocrystalline cerium dioxide (NCD) on the morphological state of the gastric mucosa and colon in rats of different ages. It was found the degenerative changes and dysregeneration (violation the ratio of value of major and parietal cells), atrophic or hyperplastic changes. NCD restored the processes of differentiation and proliferation of epithelial cells of gastric glands. In the control group of old rats mucosa of the colon was focal thinner, the cells had degenerative changes, it was observed the change in nuclear-cytoplasmic ratio of cells, were found foci of infiltration of lymphocytes, macrophages, plasma cells. NCD in old rats caused a decrease in the number of cells in a state of degeneration and apoptosis, increased proliferative activity of cells increased the number of goblet cells. Thus, NCD restored morpho-functional structure of the mucous of the stomach and colon.

Morphological variation within and among six populations of Trillium erectum in southern Ontario

1987 ◽  
Vol 65 (11) ◽  
pp. 2450-2457 ◽  
Author(s):  
Gordon S. Ringius ◽  
Jerry G. Chmielewski
Keyword(s):  
Morphological Variation ◽  
Phenotypic Variation ◽  
Population Differentiation ◽  
Plant Size ◽  
Southern Ontario ◽  
General Symmetry ◽  
Precambrian Rocks ◽  
Aerial Shoot ◽  
Several Variables ◽  
Complex Relationships

Phenotypic variation within populations and among populations was examined in six populations of Trillium erectum from southern Ontario. The general symmetry of the flower was confirmed, although there was a tendency for the lower petals and sepals to be longer than the upper ones. Within populations, variation related to the overall expansion of the aerial shoot after emergence from the soil accounted for most of the variation. However, the expansion of the shoot was not uniform and independent growth components were found for the floral and vegetative variables. Only about one-third of the variation in floral variables was dependent on plant size. Also, within the flower, anthers, and filaments varied independently. Among-population differentiation was high and appeared to be determined by complex relationships among variables that are unique to each population. Several variables showed a correlation with underlying bedrock: populations located on Paleozoic limestone consist of plants that are smaller than those in populations located on Precambrian rocks. Whether the correlation between plant size and parental bedrock is causal is unknown.

scholarly journals Pineal Gland Morphology in Relation to Age and Season in Three Canidae Species

2019 ◽  
Vol 36 (04) ◽  
pp. 247-254
Author(s):  
Svetlana Kalinina ◽  
Viktor Ilyukha ◽  
Lyudmila Uzenbaeva
Keyword(s):  
Pineal Gland ◽  
Morphological Changes ◽  
Nyctereutes Procyonoides ◽  
Raccoon Dog ◽  
Silver Fox ◽  
Reticular Fibers ◽  
Different Ages ◽  
Blue Fox ◽  
Species Specific ◽  
Insight Into

Abstract Introduction The aim of the present study was to determine the morphological features of the pineal gland in three closely related Canidae species (raccoon dog, Nyctereutes procyonoides Gray, 1834; silver fox, Vulpes vulpes L., 1758; and blue fox, Vulpes lagopus L., 1758) of different ages during the breeding (spring) and nonbreeding (winter) periods. Materials and Methods Histological analysis of the pineal glands of canids was performed. Results The morphological changes in the pineal gland detected in the current study are either age-associated, including increase in the reticular fibers and vascularization in the studied species, as well as increase in the amount of the protruding septae in the blue fox, or seasonally related, including an increase in the number and size of blood vessels. The present work reported two types of pigments: lipofuscin (primarily in the silver fox) and melanin (primarily in the raccoon dog and in the blue fox). The pineal gland in the blue fox is characterized by the ability to form corpora arenacea. Conclusions The present study provides the first insight into the morphological changes of the pineal gland in three closely related Canidae species of different ages during the breeding (spring) and nonbreeding (winter) periods, and showed some species-specific features of gland morphology. The aspects concerning the biogenesis of the calcium concretions and the factors influencing the accumulation of pigments need further investigation.

scholarly journals Morphological variation among populations of Hemigrammus coeruleus (Characiformes: Characidae) in a Negro River tributary, Brazilian Amazon

2017 ◽  
Vol 15 (1) ◽  
Author(s):  
Henrique Lazzarotto ◽  
Thiago Barros ◽  
José Louvise ◽  
Érica Pellegrini Caramaschi
Keyword(s):  
Morphological Variation ◽  
Phenotypic Variation ◽  
Population Level ◽  
Brazilian Amazon ◽  
Additional Species ◽  
Geometric Morphometric ◽  
Blackwater River ◽  
Ecological Selection ◽  
Negro River ◽  
Morphological Differences

ABSTRACT We explored patterns of phenotypic variation in Hemigrammus coeruleus from the Unini River basin, a blackwater river in the Brazilian Amazon. Geometric morphometrics was used to evaluate variation in body shape among populations from four tributaries (UN2-UN5). We found no evidence for sexual dimorphism in body size and shape. However, morphological differences among populations were detected as the analyses recovered significant groups corresponding to each sub-basin, with some overlap among them. The populations from UN2, UN3 and UN5 had more elongate bodies than fish from UN4. The most morphologically divergent population belonged to UN4, the tributary with the most divergent environmental conditions and the only one with seasonally-muddy waters. The morphological variation found among these populations is likely due to phenotypic plasticity or local adaptation, arising as a product of divergent ecological selection pressures among sub-basins. This work constitutes one of the first to employ a population-level geometric morphometric approach to assess phenotypic variation in Amazonian fishes. This method was able to distinguish subtle differences in body morphology, and its use with additional species can bring novel perspectives on the evaluation of general patterns of phenotypic differentiation in the Amazon.

scholarly journals Patterns of evolution in North American Neogene mammals

1992 ◽  
Vol 6 ◽  
pp. 146-146
Author(s):  
Louis Jacobs ◽  
Christine Janis
Keyword(s):  
Late Miocene ◽  
North American ◽  
Morphological Changes ◽  
Ground Squirrels ◽  
Deer Mice ◽  
Leg Length ◽  
Vegetational Change ◽  
Late Neogene ◽  
Tree Squirrels

The Neogene of North American represents a time of climatic change from an initially warm, non-arid climate to one with the development of increasing aridity, with warming temperatures through the early part and fluctuating (but basically cooler) temperatures through the later part. This reflects the classic story of a vegetational change from woodland to savanna and eventually to prairie. Note that the transition to true savanna in the Late Miocene was considerably earlier than the first savannas in the Pliocene of the Old World. The evolutionary trends in mammals reflect these climactic and vegetational changes.Some general broad trends are as follows: the replacement of terrestrial and subfossorial moles and geomyid rodents with more specialized fossorial ones; a decrease in the diversity of brachydont rodents and an increase in the diversity of hypsodont ones (including saltatorial forms), and a late Neogene diversification of microtines and deer mice; a decline in the diversity of tree squirrels and terrestrial beavers, and an increase in diversity of ground squirrels and aquatic beavers; the replacement of carnivores belong to more archaic families by more modern types; taxa and an increase in body size, leg length, and hypsodonty in most ungulate taxa, including oreodonts, protoceratids, camelids, antilocaprids, rhinos and equine horses although a couple of taxa show an apparent reversal of these trends: dromomerycids (cervoids) and some anchitherine horses show other morphological changes that suggest progressively more woodland-adapted (rather than savanna-adapted) forms. Tapirs and (to a lesser extent) peccaries seem little affected by the Neogene changes, and persist until the Recent.The Neogene was also punctuated by immigration events (primarily from Asia) and extinctions. The start of the Neogene shows surprisingly little change, with many Paleogene “holdovers”: some new forms appear as either the result of evolution in situ (e.g. equine horses and osteoborine dogs) or as immigrants (e.g. chalicotheres and hemicyonine “dog bears”). The initial major immigrations are during the late Early Miocene, marked by the Asian appearances of true felids (replacing the “false saber-tooths” or nimravids), pecoran ruminants (replacing the hypertragulids), more derived rhinos (replacing the diceratherine rhinos), neomustelids and procyonids. Archaic suoids such as anthracotheres and entelodonts become extinct at this time, and only the more derived ticholeptine oreodonts survive this period. The start of the Middle Miocene is notable for the appearance of proboscideans and deer mice. The Late Miocene sees the decline and eventual disappearance of hedgehogs, archaic carnivores (hemicyonine bears and amphicyonids), most browsing ungulates (oreodonts, protoceratids, many camelids, anchitherine horses, dromomerycids, merycodontine antilocaprids, hornless ruminants, chalicotheres, bunodont gomphotheres), and rhinos. New taxa appearing including ursine bears (immigrants), oversized camels and more derived gomphotheres (in situ evolution). The Pliocene marks a new wave of immigration: microtines, hyenas, true saber-tooths, and cervids come in from Asia; ground sloths (two families appearing in the Late Miocene), glyptodonts, armadillos and capybaras come in from South America. Most mammals that survived the end Miocene extinctions persist, but for many of them (such as horses, camels and antilocaprids) the generic diversity is greatly reduced.

Phenotypic variation in residual food intake of mice at different ages and its relationship with efficiency of growth, maintenance and body composition

1996 ◽  
Vol 63 (1) ◽  
pp. 149-157 ◽  
Author(s):  
J. A. Archer ◽  
W. S. Pitchford
Keyword(s):  
Body Composition ◽  
Body Weight ◽  
Weight Gain ◽  
Food Intake ◽  
Phenotypic Variation ◽  
Growth Efficiency ◽  
Maintenance Requirement ◽  
Different Ages ◽  
Selection For ◽  
Young Mice

AbstractFood intake and body weight of 119 mice was measured from 3 to 18 weeks of age. Residual food intake was calculated for each week as the variation in food intake independent of variation in weight gain, weight maintained and sex. Growth efficiency and maintenance requirement were calculated by fitting curves to data from 3 to 18 weeks. The repeatability of residual food intake was low in young mice, but increased as they matured. Growth efficiency was correlated with residual food intake in very young mice. Residual food intake was not correlated with maintenance requirement in young mice, but as mice matured the correlation of residual food intake with maintenance requirement increased to 0·6. Body composition at maturity was correlated with residual food intake and maintenance requirement of mature mice, but a large proportion of the variation in residual food intake and maintenance requirement was independent of body composition. The results suggest that the age at which residual food intake is measured is important if it is to be used as a criterion for selection for efficiency.

scholarly journals Morphofunctional changes in the rat's liver of different ages after L-methionine administration

2022 ◽  
Vol 12 (1) ◽  
pp. 125-137
Author(s):  
Roman Yanko ◽  
Elena Chaka ◽  
Mikhail Levashov
Keyword(s):  
Succinate Dehydrogenase ◽  
Dehydrogenase Activity ◽  
Protein Concentration ◽  
Morphological Changes ◽  
Liver Parenchyma ◽  
Synthetic Activity ◽  
Standard Diet ◽  
Energy Potential ◽  
Succinate Dehydrogenase Activity ◽  
Different Ages

Background: Literature data on the effect of methionine on functional activity and, especially, on morphological changes in the liver parenchyma in animals of different ages are sporadic, and research results are often ambiguous. Aim: The purpose of this work was to study and compare the morphofunctional changes in the liver of rats of different ages on prolonged administration of L-methionine. Material and Methods: The experiment was performed on 48 male Wistar rats of 3 and 15 months of age. Animals of the experimental group received L-methionine at a dose of 250 mg/kg body weight in addition to the standard diet, daily for 21 days. Histological preparations were prepared from liver tissue by a standard technique. Morphometry was performed on digital images using the computer program «Image J». Succinate dehydrogenase activity and protein concentration were determined in the suspension of hepatocyte mitochondria. Results: It was revealed that 21-day administration of L-methionine to rats led to hypertrophy of the hepatocyte nucleus, an increase in the nuclear-cytoplasmic ratio, the number of binuclear hepatocytes, and the nucleolus in the cell nucleus. The relative area of ​​the sinusoids network increased by 50% in 3-month-old animals. This indicated a better blood filling of the liver parenchyma. The increase in succinate dehydrogenase activity and protein concentration was revealed in the suspension of hepatocyte mitochondria of the experimental rats. This indicated an increase in the mitochondria energy potential and protein-synthetic activity. Conclusions: The administration of prophylactic doses of methionine to healthy rats leads to the appearance of pronounced morphological and functional signs of increased activity of hepatocytes. The severity of this effect has a distinct age-dependent character. In young rats, it is more pronounced than in mature rats. The results of the study are important for practical medicine when using methionine for therapeutic and prophylactic purposes.

scholarly journals Variation in the pelvic and pectoral girdles of Australian Oligo–Miocene mekosuchine crocodiles with implications for locomotion and habitus

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3501 ◽  
Author(s):  
Michael D. Stein ◽  
Adam Yates ◽  
Suzanne J. Hand ◽  
Michael Archer
Keyword(s):  
Morphological Variation ◽  
Middle Miocene ◽  
Iliac Crest ◽  
Morphological Changes ◽  
Parsimony Analysis ◽  
Crown Group ◽  
Hunting Strategies ◽  
Pelvic Limb ◽  
Relationship Of ◽  
Cranial Shape

Australian Oligo–Miocene mekosuchines (Crocodylia; Crocodyloidea) display wide diversity in cranial shape and inferred hunting strategies. Terrestrial habitus has been inferred for these distinctive predators. A direct morphological signal for locomotion can be expected in the postcrania, particularly the pelvic and pectoral girdles. Here we describe fossil materials of the girdles, which chart their morphological variation in the subfamily from Eocene through to Middle Miocene. Over this period, both girdles undergo significant morphological changes. Notably, an enclosed, ventrally orientated acetabulum in the ilium is developed in one lineage. This recapitulates the erect parasagittal configuration of the pelvic limb seen in many Mesozoic crocodylomorph lineages, suggesting consistent use of erect high-walking in these mekosuchines. Other pelves from the same Oligo–Miocene deposits display morphology closer to modern crocodilians, suggesting a partitioning of locomotory strategy among sympatric mekosuchines. Plesiomorphic and derived pelvic girdles are distinguishable by parsimony analysis, and the earliest examples of the mekosuchine pelvis more closely resemble gavialids and alligatorids while latter forms converge on crown group crocodylids in the morphology of the iliac crest. This suggests that a revaluation of the base relationship of Mekosuchinae within Eusuchia is necessary.

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