scholarly journals Evidence for general size‐by‐habitat rules in actinopterygian fishes across nine scales of observation

2021 ◽  
Author(s):  
John T. Clarke
Keyword(s):  
Actinopterygian Fishes ◽  
General Size

Ultrastructural Alterations in Sinusoidal Endothelial Fenestrae as a Result of Hypoxia

1976 ◽  
Vol 34 ◽  
pp. 168-169
Author(s):  
Waykin Nopanitaya ◽  
Raeford E. Brown ◽  
Joe W. Grisham ◽  
Johnny L. Carson
Keyword(s):  
Endothelial Cells ◽  
Experimental Model ◽  
Hepatic Lobule ◽  
Ultrastructural Alterations ◽  
Large Type ◽  
Sinusoidal Endothelial Fenestrae ◽  
General Size ◽  
Sem Studies

Mammalian endothelial cells lining hepatic sinusoids have been found to be widely fenestrated. Previous SEM studies (1,2) have noted two general size catagories of fenestrations; large fenestrae were distributed randomly while the small type occurred in groups. These investigations also reported that large fenestrae were more numerous and larger in the endothelial cells at the afferent ends of sinusoids or around the portal areas, whereas small fenestrae were more numerous around the centrilobular portion of the hepatic lobule. It has been further suggested that under some physiologic conditions small fenestrae could fuse and subsequently become the large type, but this is, as yet, unproven.We have used a reproducible experimental model of hypoxia to study the ultrastructural alterations in sinusoidal endothelial fenestrations in order to investigate the origin of occurrence of large fenestrae.

Some new and known species of Bomolochidae (Copepoda, Cyclopoida) parasitic on Japanese actinopterygian fishes, 3

Crustaceana ◽  
2021 ◽  
Vol 94 (4) ◽  
pp. 447-465
Author(s):  
Kunihiko Izawa
Keyword(s):  
Male Specimen ◽  
Actinopterygian Fishes ◽  
Dorsal Process ◽  
First Time ◽  
Respective Species ◽  
Copepoda Cyclopoida

Abstract Orbitacolax bispinus sp. nov., Orbitacolax leptoscari (Yamaguti, 1953), Paraorbitacolax sphyraenae Izawa, 2021, and one male specimen of a Bomolochidae sp. are (re)described. The male and copepodid V female of O. leptoscari, and the male and copepodid V male of P. sphyraenae are described for the first time for the respective species. A description performed in Izawa (2020, 2021) that the maxilliped of the female bears a dorsal process in Orbitacolax and Paraorbitacolax spp., was wrong and is herein corrected.

Prosopanche cocuccii (Hydnoraceae): a new species from Southern Brazil

Phytotaxa ◽  
2021 ◽  
Vol 521 (3) ◽  
pp. 177-192
Author(s):  
JORDANO D. TAVARES DE CARVALHO ◽  
CATARINE MARKUS ◽  
ALDO MEROTTO JUNIOR ◽  
RENATO A. ZÁCHIA ◽  
MARILIA SCHUCH ◽  
...  
Keyword(s):  
New Species ◽  
Nicotiana Tabacum ◽  
Host Plant ◽  
Morphological Characteristics ◽  
Southern Brazil ◽  
Habitat Ecology ◽  
Single Host ◽  
Flower Organs ◽  
General Size ◽  
A New Species

Prosopanche cocuccii is described as a new species from Southern Brazil. It resembles P. bonacinae due to the trigonous rhizome and by the general size of the flower organs. Nevertheless, P. cocuccii is distinguished by the main floral morphological characteristics used to differentiate species. In addition, the new species presents some rare characters for the genus, such as a highly branched rhizome and flowers usually grouped in fascicles. We provide a description, illustrations, field photographs, morphological details under the stereomicroscope, and comments on habitat, ecology, distribution, and conservation of the new species, as well as an updated key for the genus Prosopanche. In addition, we identified that P. cocuccii produces a large number of rhizomes and fruits for each single host specimen of tobacco (Nicotiana tabacum), which resulted in a decrease in height and growth of its only known host plant.

Pectoral and Pelvic Muscles of Actinopterygian Fishes

2018 ◽  
pp. 293-304
Author(s):  
Rui Diogo ◽  
Janine M. Ziermann ◽  
Julia Molnar ◽  
Natalia Siomava ◽  
Virginia Abdala
Keyword(s):  
Actinopterygian Fishes ◽  
Pelvic Muscles

scholarly journals VAIZDO FORMOS SUVOKIMO APRAŠOMASIS MODELIS

Psichologija ◽  
2005 ◽  
Vol 31 ◽  
pp. 113-123
Author(s):  
Rimantas Grikšas
Keyword(s):  
Crucial Role ◽  
Form Perception ◽  
Descriptive Model ◽  
Perception System ◽  
Mathematical Algorithms ◽  
Linear Module ◽  
General Size ◽  
Frontal Projection ◽  
Main Module

Straipsnyje nagrinėjamas daikto (objekto) formos suvokimas. Daikto forma suvokiama (determinuojama) sulyginant atskirus jo parametrus. Išskirti trys pagrindiniai suvokimo būdai: 1) kampinių dydžių; 2) linijinių dydžių (atstumų); 3) kreivių.Visais atvejais, suvokiant formą, atskiri parametrai lyginami su moduliu. Kampinių dydžių suvokimo modulis yra 90° (status) kampas ir jo kartotiniai, t. y. 180°, 270° ir 360° kampai. Kitais dviem atvejais modulis yra didžiausias objekto gabarito matmuo, lygiagretus su simetrijos ašimi. Parametras suvokiamas kaip artimas matmeniui modulio dalmuo. Pagrindinis objekto modulis turi lemiamą reikšmę išskiriant objektą iš aplinkos, tai yra suvokimo procese atliekant fragmentaciją ir sujungiant atskirus fragmentus į visumą. Suvokiamų proporcijų dydžiai yra suapvalinami iki artimų nedidelių sveikųjų skaičių santykių. Taip sumažinamas apdorojamos informacijos kiekis. Duomenys analizei gauti atliekant bandymus ir analizuojant vaizduojamojo meno kūrinius, padarius prielaidą, kad vaizduojamasis menas atspindi formos suvokimo sistemą, t. y. menininkas vaizduoja daikto formą jau supaprastintomis parametrų proporcijomis. Straipsnyje išnagrinėtas frontalinėje projekcijoje esančių (arba plokštuminių) objektų formos suvokimas pasitelkus parametrų proporcijas. THE DESCRIPTIVE MODEL OF PERCEPTION OF IMAGE FORMRimantas Grikšas SummaryThere is a descriptive model of form perception being analyzed in the article, and there has been used a small number of invariant samples for it. These are the samples that would not depend on various image transformations.The data for analysis has been received through tests and analysis of works of imitative arts after there had been an assumption made that imitative arts reflect the system of form perception. It means that the artist expresses the form of thing in already simplified proportions of dimensions. The article analyzes just the perception of form of the objects that are in the frontal projection, or that are plane.There was one of the features analyzed – orientation of outline fragments and their situation in the space. There were ignored such factors as texture, color of object, etc. Besides, while making the model of image formation, we have ignored such an effect of normalization, where the orientation of the object in space is corrected with respect to vertical and horizontal axes.In the perception system that is analyzed in the article the form of the thing is perceived (determined) by the comparison of particular parameters. There have been excluded three main ways of determination: 1) determination of angular values; 2) determination of linear values (distances); 3) determination of curves. In all the cases separate parameters are compared with a module. The determination module of angular values is angle of 90° (right) and its multiples, i.e. angles of 180°, 270° and 360°. In other cases the module is the biggest value of object’s gabarit that is parallel to the symmetric axis. The parameter is determined (perceived) as the ratio of value and module. The main module of the object plays a crucial role in excluding the object from environment.The recognition process consists of fragmentation of figure (separation to single parts), while the figure is defined by the set of fundamental elements. However, the question remains how to perform fragmentation and to join separate fragments into one set that makes the object. If the fragmentation is performed by attributing separate lines (parameters) to some adequation type, then the crucial role in fragmentjoining to one-piece object is played by main linear module. The exclusion of main module and its usage in the proportions while perceiving the image are the items that allow seeing the object as one set.The values of determined proportions are round down the close ratios of small whole numbers. In such a way the amount of processed information is diminished as well. Thus when the form of the object is perceived, any parameter is perceived as its closest parameter that forms a ration with main module, which is expressed in the smallest possible nature numbers.The model of form perception that is introduced in the article is close to the structuralism – one of the oldest hypotheses of perception. The main drawback of this system is the usage of big amount of the elements that form an image. The elements that form an image are the regular geometrical figures. These are traditional figures: spheres, cylinders, cones. When their image is being made their form cannot change a lot. Only the general size and proportions of gabarits may change. The authors describe these figures in purely mathematical algorithms that do not have any connection to the image. Therefore it is difficult to assemble various forms from these figures. Besides, a big number of variants of elements is needed for such a purpose.The elements that are presented in the article as the ones that form an image are dynamic figures made from the types of differently determined lines. The values that describe the figures are the parameters that are clearly perceived in the image. Moreover, main module – a parameter that integrates the object’s image – is used in the adequation of parameters. It allows describing any form of especially small amount of samples. 

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