MATHEMATICAL MODEL AND AREA OF EXISTENCE OF THE FAMILY CRANKS AND MOBILE MECHANISMS WITH THE MAXIMUM TRANSMISSION ANGLE

2020 ◽  
pp. 20-26
Author(s):  
N. A. Sereda
Keyword(s):  
Mathematical Model ◽  
New Family ◽  
Arm Span ◽  
Angle Function ◽  
Straight Line ◽  
Transmission Angle ◽  
Crank Angle ◽  
The Family ◽  
Unit Radius ◽  
Maximum Transmission

The article examines crank-rocker mechanisms. Such mechanisms are used in transport and technological machines. The article is devoted to the search for a new family of crank-rocker mechanisms. A mathematical model of a new family of crank-rocker mechanisms is obtained. In this family, the maximum transmission angle reaches 90 when the crank angle is 75. Thus, the new family of crank-rocker mechanisms differs from the known families by the position of the mechanism in which the maximum of the transmission angle function takes place. It is shown that, with a certain ratio of link lengths, the new family corresponds to the known families KKM-5 and KKM-7. The area of existence of a new family of crank-rocker mechanisms is established. This area is bounded by the arc of the circle of the unit radius and the curve. The mentioned curve is based on a joint solution of a mathematical model of a new family of mechanisms and the famous Kolchin straight line. The dependence for the minimum transmission angle is obtained. A formula for determining the angle of the rocker arm span is proposed. A graphical interpretation of the mentioned dependencies and formulas is constructed. The scope of existence of a new family of crank-rocker mechanisms and graphical interpretations are used in determining the geometric parameters of mechanisms. These mechanisms are part of a new family of mechanisms.

Three new species, two new genera, and new family Biphragmosagittidae (Сhaetognatha) from Southwest Pacific Ocean

2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characters ◽  
The Body ◽  
New Order ◽  
New Genera ◽  
New Family ◽  
The Family ◽  
Three New Species

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.

Correcting a 135-year error: Limulidae Leach, 1819 (Chelicerata, Xiphosura) is the proper authority, not Limulidae Zittel, 1885

2021 ◽  
pp. 1-2
Author(s):  
Philip M. Novack-Gottshall ◽  
Roy E. Plotnick
Keyword(s):  
Horseshoe Crab ◽  
Marine Species ◽  
Limulus Polyphemus ◽  
Junior Synonym ◽  
Living Fossil ◽  
New Family ◽  
The Family ◽  
The World ◽  
Modern Genus

The horseshoe crab Limulus polyphemus (Linnaeus, 1758) is a famous species, renowned as a ‘living fossil’ (Owen, 1873; Barthel, 1974; Kin and Błażejowski, 2014) for its apparently little-changed morphology for many millions of years. The genus Limulus Müller, 1785 was used by Leach (1819, p. 536) as the basis of a new family Limulidae and synonymized it with Polyphemus Lamarck, 1801 (Lamarck's proposed but later unaccepted replacement for Limulus, as discussed by Van der Hoeven, 1838, p. 8) and Xyphotheca Gronovius, 1764 (later changed to Xiphosura Gronovius, 1764, another junior synonym of Limulus). He also included the valid modern genus Tachypleus Leach, 1819 in the family. The primary authority of Leach (1819) is widely recognized in the neontological literature (e.g., Dunlop et al., 2012; Smith et al., 2017). It is also the authority recognized in the World Register of Marine Species (WoRMS Editorial Board, 2021).

scholarly journals Sperm Cryopreservation in American Flamingo (Phoenicopterus Ruber): Influence of Cryoprotectants and Seminal Plasma Removal

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 203
Author(s):  
María Gemma Millán de la Blanca ◽  
Eva Martínez-Nevado ◽  
Cristina Castaño ◽  
Juncal García ◽  
Berenice Bernal ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Genetic Material ◽  
First Year ◽  
Sperm Cryopreservation ◽  
Straight Line ◽  
The Family ◽  
Second Year ◽  
American Flamingo ◽  
Phoenicopterus Ruber

The American flamingo is a useful model for the development of successful semen cryopreservation procedures to be applied to threatened related species from the family Phoenicopteridae, and to permit genetic material banking. Current study sought to develop effective sperm cryopreservation protocols through examining the influences of two permeating cryoprotectants and the seminal plasma removal. During two consecutive years (April), semen samples were collected and frozen from American flamingos. In the first year, the effect of two permeating cryoprotectants, DMA (dimethylacetamide) (6%) or Me2SO (dimethylsulphoxide) (8%), on frozen–thawed sperm variables were compared in 21 males. No differences were seen between DMA and Me2SO for sperm motility, sperm viability, and DNA fragmentation after thawing. In the second year, the role of seminal plasma on sperm cryoresistance was investigated in 31 flamingos. Sperm samples were cryopreserved with and without seminal plasma, using Me2SO (8%) as a cryoprotectant. The results showed that samples with seminal plasma had higher values than samples without seminal plasma for the following sperm variables: Straight line velocity (22.40 µm/s vs. 16.64 µm/s), wobble (75.83% vs. 69.40%), (p < 0.05), linearity (62.73% vs. 52.01%) and straightness (82.38% vs. 73.79%) (p < 0.01); but acrosome integrity was lower (55.56% vs. 66.88%) (p < 0.05). The cryoresistance ratio (CR) was greater in samples frozen with seminal plasma than without seminal plasma for CR-progressive motility (138.72 vs. 54.59), CR-curvilinear velocity (105.98 vs. 89.32), CR-straight line velocity (152.77 vs. 112.58), CR-average path velocity (122.48 vs. 98.12), CR-wobble (111.75 vs. 102.04) (p < 0.05), CR-linearity (139.41 vs. 113.18), and CR-straightness (124.02 vs. 109.97) (p < 0.01). This research demonstrated that there were not differences between Me2SO and DMA to successful freezing sperm of flamingos; seminal plasma removal did not provide a benefit for sperm cryopreservation.

Early Paleozoic Hyolitha from North America: reexamination of Walcott's and Resser's type specimens

1988 ◽  
Vol 62 (2) ◽  
pp. 218-233 ◽  
Author(s):  
John Mark Malinky
Keyword(s):  
North America ◽  
Lower Cambrian ◽  
Type Species ◽  
New Genus ◽  
Early Paleozoic ◽  
Type Specimens ◽  
Middle Cambrian ◽  
Upper Cambrian ◽  
New Family ◽  
The Family

Concepts of the family Hyolithidae Nicholson fide Fisher and the genera Hyolithes Eichwald and Orthotheca Novak have been expanded through time to encompass a variety of morphologically dissimilar shells. The Hyolithidae is here considered to include only those hyolithid species which have a rounded (convex) dorsum; slopes on the dorsum are inflated, and the venter may be flat or slightly inflated. Hyolithes encompasses species which possess a low dorsum and a prominent longitudinal sulcus along each edge of the dorsum; the ligula is short and the apertural rim is flared. The emended concept of Orthotheca includes only those species of orthothecid hyoliths which have a subtriangular transverse outline and longitudinal lirae covering the shell on both dorsum and venter.Eighteen species of Hyolithes and one species of Orthotheca from the Appalachian region and Western Interior were reexamined in light of more modern taxonomic concepts and standards of quality for type material. Reexamination of type specimens of H. similis Walcott from the Lower Cambrian of Newfoundland, H. whitei Resser from the Lower Cambrian of Nevada, H. billingsi Walcott from the Lower Cambrian of Nevada, H. gallatinensis Resser from the Upper Cambrian of Wyoming, and H. partitus Resser from the Middle Cambrian of Alabama indicates that none of these species represents Hyolithes. Hyolithes similis is here included under the new genus Similotheca, in the new family Similothecidae. Hyolithes whitei is designated as the type species of the new genus Nevadotheca, to which H. billingsi may also belong. Hyolithes gallatinensis is referred to Burithes Missarzhevsky with question, and H. partitus may represent Joachimilites Marek. The type or types of H. attenuatus Walcott, H. cecrops Walcott, H. comptus Howell, H. cowanensis Resser, H. curticei Resser, H. idahoensis Resser, H. prolixus Resser, H. resseri Howell, H. shaleri Walcott, H. terranovicus Walcott, and H. wanneri Resser and Howell lack shells and/or other taxonomically important features such as a complete aperture, rendering the diagnoses of these species incomplete. Their names should only be used for the type specimens until better preserved topotypes become available for study. Morphology of the types of H.? corrugatus Walcott and “Orthotheca” sola Resser does not support placement in the Hyolitha; the affinities of these species are uncertain.

scholarly journals Amino acid residues modulating the activities of staphylococcal glutamyl endopeptidases

2010 ◽  
Vol 391 (10) ◽  
Author(s):  
Toshio Ono ◽  
Yuko Ohara-Nemoto ◽  
Yu Shimoyama ◽  
Hisami Okawara ◽  
Takeshi Kobayakawa ◽  
...  
Keyword(s):  
Family Members ◽  
Glutamyl Endopeptidase ◽  
Peptidase Activity ◽  
Amino Acid Residues ◽  
Virulence Determinants ◽  
Cloning And Sequencing ◽  
New Family ◽  
The Family ◽  
N Terminus ◽  
Staphylococcus Epidermis

AbstractThe glutamyl endopeptidase family of enzymes from staphylococci has been shown to be important virulence determinants of pathogenic family members, such asStaphylococcus aureus. Previous studies have identified the N-terminus and residues from positions 185–195 as potentially important regions that determine the activity of three members of the family. Cloning and sequencing of the new family members fromStaphylococcus caprae(GluScpr) andStaphylococcus cohnii(GluScoh) revealed that the N-terminal Val residue is maintained in all family members. Mutants of the GluV8 enzyme fromS. aureuswith altered N-terminal residues, including amino acids with similar properties, were inactive, indicating that the Val residue is specifically required at the N-terminus of this enzyme family in order for them to function correctly. Recombinant GluScpr was found to have peptidase activity intermediate between GluV8 and GluSE fromStaphylococcus epidermisand to be somewhat less specific in its substrate requirements than other family members. The 185–195 region was found to contribute to the activity of GluScpr, although other regions of the enzyme must also play a role in defining the activity. Our results strongly indicate the importance of the N-terminal and the 185–195 region in the activity of the glutamyl endopeptidases of staphylococci.

Palaeonema phyticum gen. n., sp. n. (Nematoda: Palaeonematidae fam. n.), a Devonian nematode associated with early land plants

Nematology ◽  
2008 ◽  
Vol 10 (1) ◽  
pp. 9-14 ◽  
Author(s):  
George Poinar Jr ◽  
Hans Kerp ◽  
Hagen Hass
Keyword(s):  
Early Stage ◽  
Land Plant ◽  
Terrestrial Plants ◽  
Early Devonian ◽  
Plant Parasitism ◽  
New Family ◽  
The Earth ◽  
The Family ◽  
The Face ◽  
Early Land

AbstractNematodes are one of the most abundant groups of invertebrates on the face of the earth. Their extremely poor fossil record hinders our ability to assess just when members of this group invaded land and first became associated with plants. This study reports fossil nematodes from the stomatal chambers of the Early Devonian (396 mya) land plant, Aglaophyton major. These nematodes, which are tentatively assigned to the order Enoplia, are described as Palaeonema phyticum gen. n., sp. n. in the new family Palaeonematidae fam. n. Diagnostic characters of the family are: i) cuticular striations; ii) uniform, cylindrical pharynx with the terminal portion only slightly set off from the remainder; and iii) a two-portioned buccal cavity with the upper portion bearing protuberances. The presence of eggs, juveniles and adults in family clusters within the plant tissues provide the earliest evidence of an association between terrestrial plants and animals and may represent an early stage in the evolution of plant parasitism by nematodes.

Applanodictyosporous Pleosporales: Clathrospora, Comoclathris, GraphyIlium, Macrospora, and Platysporoides

1992 ◽  
Vol 70 (8) ◽  
pp. 1617-1658 ◽  
Author(s):  
R. A. Shoemaker ◽  
C. E. Babcock
Keyword(s):  
Key Words ◽  
New Genus ◽  
New Family ◽  
The Family

Six genera of the order Pleosporales are revised taxonomically. Although five genera have unusual applanate ascospores, they are members of three different families. Clathrospora (10 species, 2 new), Comoclathris (21 species, 7 new), and Macrospora (3 species) are placed in a new family Diademaceae in which the ascoma opening is a characteristic flat circular lid. Diademosa, a new genus with one species with terete ascospores is placed in Diademaceae. Graphyllium (3 species) is placed in the family Hysteriaceae characterized by hysterothecia with a slit-like opening. Platysporoides n.gen. (11 species, 1 new) is maintained in the Pleosporaceae because of the terete pored beak of the ascomata. Key words: Pleosporales, applanate ascospores, Clathrospora, Comoclathris, Macrospora, Diademosa, Graphyllium, Platysporoides.

An Efficient Weighted Residual Time Integration Family

2021 ◽  
pp. 2150106
Author(s):  
Mohammad Rezaiee-Pajand ◽  
S. A. H. Esfehani ◽  
H. Ehsanmanesh
Keyword(s):  
Degrees Of Freedom ◽  
Time Integration ◽  
Nonlinear Damping ◽  
Implicit Methods ◽  
New Family ◽  
Error Analyses ◽  
Damping Behavior ◽  
The Family ◽  
New Strategy ◽  
Time Integration Methods

A new family of time integration methods is formulated. The recommended technique is useful and robust for the loads with large variations and the systems with nonlinear damping behavior. It is also applicable for the structures with lots of degrees of freedom, and can handle general nonlinear dynamic systems. By comparing the presented scheme with the fourth-order Runge–Kutta and the Newmark algorithms, it is concluded that the new strategy is more stable. The authors’ formulations have good results on amplitude decay and dispersion error analyses. Moreover, the family orders of accuracy are [Formula: see text] and [Formula: see text] for even and odd values of [Formula: see text], respectively. Findings demonstrate the superiority of the new family compared to explicit and implicit methods and dissipative and non-dissipative algorithms.

Comments on “Is Copytus Skogsberg, 1939 (Crustacea: Ostracoda) a neocytherideid? With description of a new family and two new species” by Coimbra, Bergue & Ramos (2020)

Zootaxa ◽  
2021 ◽  
Vol 4950 (2) ◽  
pp. 398-400
Author(s):  
OKAN KÜLKÖYLÜOĞLU
Keyword(s):  
New Species ◽  
Integrated Approach ◽  
Taxonomic Position ◽  
New Family ◽  
As Species ◽  
Diagnostic Characteristics ◽  
The Family ◽  
Two New Species

Most recently, Coimbra et al. (2020) published an article in this journal (Zootaxa, 4729 (2): 177–194) questioning the taxonomic position of the genus Copytus Skogsberg, 1939 (Crustacea, Ostracoda) along with proposing it as the type genus of their new family (Copytidae Coimbra et al., 2020), and erecting two new species that were listed by previous authors as Copytus sp. 1 and Copytus sp. 2. The main diagnostic characteristics of their new proposed family (and the genus Copytus) are the hinge type and muscle scars on the carapace and/or valves (see lines 6–8 from the bottom, p. 179 in Coimbra et al. 2020). They also underlined that (p. 179) “...this study is based exclusively on the morphology of the animals’ hard parts”. While the authors considered another genus (Neocopytus) proposed by Külköylüoğlu, Colin & Kılıç (2007) of the family Neocytherididae as invalid, they interestingly transferred some species of Neocopytus to Copytus as species of their new family (Coimbra et al. 2020). Herein, my point with the comments listed below is to clarify that, when possible, both soft and hard parts should be considered in taxonomy, and such an integrated approach clearly indicates that Neocopytus is a valid and taxonomically useful genus. 

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