IV.—Studies on the Functional Morphology and Feeding Mechanism ofMonodella argentariiStella (Crustacea: Thermosbænacea)

1964 ◽  
Vol 66 (4) ◽  
pp. 49-90 ◽  
Author(s):  
Geoffrey Fryer

SynopsisStructural features related to habits of life are described for the thermosbænaceanMonodella argentarii.Although it can swim, this minute malacostracan is essentially benthic in habits, and its food consists of bottom detritus. The collection and subsequent manipulation of food are described.Monodellais not a filter feeder and no currents are involved in the feeding process which consists essentially of scraping, brushing and pushing. Cephalic appendages only are involved. The structure and mode of action of the mouthparts are described and illustrated in detail, and the functional significance of many structural features is explained.No justification is found for placing the Thermosbænacea in a separate division, the Pancarida, and its position within the Peracarida is discussed.The past history and present distribution of the Thermosbænacea are reconsidered.

1963 ◽  
Vol 65 (14) ◽  
pp. 335-381 ◽  
Author(s):  
Geoffrey Fryer

SynopsisOutstanding structural features related to habits of life in the chydorid cladoceranEurycercus lamellatusare described. Crawling is as important as swimming in this deposit-feeding species. The nature of the food, its collection and subsequent manipulation, are described. Both cephalic and trunk appendages are involved in this process. Their structure and mode of action are described and illustrated in detail. Many hitherto unknown structural features are described and the functional significance of these and other morphological peculiarities is explained.


1964 ◽  
Vol 20 ◽  
pp. 37-37
Author(s):  
R. H. Stoy

Information about the past history of the Galaxy may be obtained from a two-colour diagram, since the present distribution of stars in such a diagram depends on the past rate of star formation and the past metal abundances in the interstellar medium. As an illustration of this, I would like to discuss three diagrams that were recently prepared by Dr. M. E. Dixon from Cape photometric data (Dixon 1963a,b).


1988 ◽  
Vol 62 (01) ◽  
pp. 83-87 ◽  
Author(s):  
Patricia H. Kelley ◽  
Charles T. Swann

The excellent preservation of the molluscan fauna from the Gosport Sand (Eocene) at Little Stave Creek, Alabama, has made it possible to describe the preserved color patterns of 15 species. In this study the functional significance of these color patterns is tested in the context of the current adaptationist controversy. The pigment of the color pattern is thought to be a result of metabolic waste disposal. Therefore, the presence of the pigment is functional, although the patterns formed by the pigment may or may not have been adaptive. In this investigation the criteria proposed by Seilacher (1972) for testing the functionality of color patterns were applied to the Gosport fauna and the results compared with life mode as interpreted from knowledge of extant relatives and functional morphology. Using Seilacher's criteria of little ontogenetic and intraspecific variability, the color patterns appear to have been functional. However, the functional morphology studies indicate an infaunal life mode which would preclude functional color patterns. Particular color patterns are instead interpreted to be the result of historical factors, such as multiple adaptive peaks or random fixation of alleles, or of architectural constraints including possibly pleiotropy or allometry. The low variability of color patterns, which was noted within species and genera, suggests that color patterns may also serve a useful taxonomic purpose.


Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.


Author(s):  
Magdalena Zarzyka-Ryszka

The paper describes the past and present distribution of Colchicum autumnale in the vicinity of Cracow, highlights the role of Stanisław Dembosz (who published the first locality of C. autumnale near Igołomia in 1841). Gives information about the occurrence of C. autumnale in Krzeszowice in the 19th century (reported by Bronisław Gustawicz), presents new localities noted in 2012–2014 in meadows in the north-eastern part of the Puszcza Niepołomicka forest and adjacent area (between the Vistula and Raba rivers), and gives a locality found in Cracow in 2005 (no longer extant).


Author(s):  
Mohamed Ibrahim Elzagheid

: Nucleosides and their analogues have been in use for many years and have become essential for treating patients with viral infections. Many additional nucleoside drugs have been approved over the past decades. This strongly demonstrates how important these compounds are and the crucial role they play. Given that a significant amount of research and literature has been documented regarding nucleoside analogues, this review article mainly focuses the discussion on nucleosides and nucleoside analogous that have proven to play significant role or be emerging in the treatment of known viral infections. This covers the names, structures, applications, toxicity, and mode of action of relevant nucleoside analogues.


Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 330
Author(s):  
Timofey V. Malyarenko ◽  
Alla A. Kicha ◽  
Valentin A. Stonik ◽  
Natalia V. Ivanchina

Sphingolipids are complex lipids widespread in nature as structural components of biomembranes. Commonly, the sphingolipids of marine organisms differ from those of terrestrial animals and plants. The gangliosides are the most complex sphingolipids characteristic of vertebrates that have been found in only the Echinodermata (echinoderms) phylum of invertebrates. Sphingolipids of the representatives of the Asteroidea and Holothuroidea classes are the most studied among all echinoderms. In this review, we have summarized the data on sphingolipids of these two classes of marine invertebrates over the past two decades. Recently established structures, properties, and peculiarities of biogenesis of ceramides, cerebrosides, and gangliosides from starfishes and holothurians are discussed. The purpose of this review is to provide the most complete information on the chemical structures, structural features, and biological activities of sphingolipids of the Asteroidea and Holothuroidea classes.


2021 ◽  
pp. 155708512098763
Author(s):  
Emily M. Wright ◽  
Gillian M. Pinchevsky ◽  
Min Xie

We consider the broad developments that have occurred over the past decade regarding our knowledge of how neighborhood context impacts intimate partner violence (IPV). Research has broadened the concept of “context” beyond structural features such as economic disadvantage, and extended into relationships among residents, collective “action” behaviors among residents, cultural and gender norms. Additionally, scholars have considered how the built environment might foster (or regulate) IPV. We now know more about the direct, indirect, and moderating ways that communities impact IPV. We encourage additional focus on the policy implications of the research findings.


2017 ◽  
Vol 37 (2) ◽  
pp. 51-70 ◽  
Author(s):  
Muhammad Iqbal ◽  
Saqib Ali ◽  
Ali Haider ◽  
Nasir Khalid

AbstractOrganotin complexes are being extensively studied and screened for their therapeutic potential. Although many recent advances and achievements in this field have been made, the exact mode of action of these complexes is yet to be unveiled. In the present review, an attempt has been made to correlate the therapeutic properties of organotin complexes with their structural features and the environment in which these interact with biological systems. The mechanism, various modes of interaction with biological systems, and physiological target sites of organotin complexes have been highlighted as well.


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