DQB1*0202and the newDQB1*0203allele: a fourth pair ofDQB1alleles differing only at codon 57

1997 ◽  
Vol 49 (3) ◽  
pp. 271-273 ◽  
Author(s):  
O. Olerup ◽  
A. Aldener-Cannavá ◽  
A. Fogdell-Hahn ◽  
R. R. Getty ◽  
D. R. Wagenknecht ◽  
...  
Keyword(s):  
Fourth Pair

The Role of the ‘Walking Legs’ in Aquatic and Terrestrial Locomotion of the Crayfish Austropotamobius Pallipes (Lereboullet)

1975 ◽  
Vol 62 (2) ◽  
pp. 447-454 ◽  
Author(s):  
CAROLINE M. POND
Keyword(s):  
The Body ◽  
Hydrodynamic Drag ◽  
Terrestrial Locomotion ◽  
Austropotamobius Pallipes ◽  
The Third ◽  
Fourth Pair

1. The hydrodynamic drag acting on the crayfish Austropotamobius pallipes is measured and it is concluded that, in the range of velocities used in walking, the drag is independent of the posture of the limbs and the direction of motion of the body. At swimming velocities the streamlining caused by promotion of the legs reduces the drag losses to half that of a crayfish moving in the forwards walking posture at the same speed. 2. The forwards walking of intact crayfish is compared with that of the same animal after amputation of one or more pairs of legs. It is concluded that the third and fourth pair of legs provide most of the propulsion under water and the second pair is not essential to locomotion under any of the conditions tried.

Three new genera of zerconid mites (Acari, Gamasida: Zerconidae) from the United States of America

1981 ◽  
Vol 59 (10) ◽  
pp. 2038-2047 ◽  
Author(s):  
C. Błaszak
Keyword(s):  
United States ◽  
United States Of America ◽  
Type Species ◽  
The United States ◽  
New Genera ◽  
The Family ◽  
Single Opening ◽  
Fourth Pair

Three new monotypic genera in the family Zerconidae (Acari: Gamasida) from the United States are described: Krantzas gen.nov. (type species K. mirificus sp.nov.), Lindquistas gen.nov. (type species. L. amyihetes sp.nov.), and Hypozercon gen.nov. (type species. H. macleani sp.nov.). Krantzas is related to genera characterized by absence both of adgenital shields and a single opening of glands gv2, and is also related to genera characterized by peritremal shields terminating truncately behind the fourth pair of coxae. In this genus the additional lateroventral shield is situated between the peritremal and ventroanal shields. Lindquistas is related to genera characterized by the peritremal shield terminating truncately behind the fourth pair of coxae and by having two short, smooth peritremal setae. Members of this genus are similar to those of Macrozercon Błaszak and Bledas Halašková. Hypozercon is related to genera characterized by having the peritremal shields extended posteriorly and having two unequal setae on the peritremal shield. Members of this genus are similar to those of Mesozercon Błaszak and Neozercon Petrova.

The cytogenetics of the differences between some Secale species

1955 ◽  
Vol 46 (3) ◽  
pp. 377-383 ◽  
Author(s):  
Ralph Riley
Keyword(s):  
Secale Cereale ◽  
Chromosome Structure ◽  
Plant Morphology ◽  
Structural Condition ◽  
Evolutionary Significance ◽  
Seed Parent ◽  
Ear Morphology ◽  
The Cross ◽  
Fourth Pair

1. The seed of crosses of Secale cereale with S. montanum and S. dalmaticum germinated only when S. cereale was the seed parent.2. S. cereale was found to differ from S. montanum and S. dalmaticum by two large translocations involving three pairs of chromosomes, and a small translocation involving a fourth pair. The fertility of the F1 plants was low, and in ear morphology and perennial habit they were similar to the S. montanum and S. dalmaticum parents.3. S. montanum and S. dalmaticum were found to be similar in gross chromosome structure and their hybrids were phenotypically intermediate and fertile.4. The F2 of the cross S. cereale x S. dalmaticum consisted of three types, in terms of chromosome structural condition and plant morphology, those like one or other parent and those like the F1.5. The genetic and evolutionary significance of this situation is discussed, together with the problem of the fixation of translocations in populations.

New data on tardigrades of the genus Milnesium (Tardigrada, Eutardigrada, Milnesiidae) from the Russian Far East, obtained using the method of molecular barkoding

2021 ◽  
Vol 32 ◽  
pp. 114-122
Author(s):  
E.V. Maskin ◽  
◽  
P.V. Grebenkin ◽  
L.V. Zheleznova ◽  
D.V. Tumanov ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Russian Far East ◽  
Far East ◽  
Integrative Taxonomy ◽  
Biological Data ◽  
The Third ◽  
Thickened Cuticle ◽  
The Russian Far East ◽  
Fourth Pair

A study of terrestrial tardigrades of the genus Milnesium Doyère, 1840 collected in Russky Island (Primorsky kray, Vladivostok) was carried out using the methods of integrative taxonomy, including the analysis of morphological and molecular biological data. Three species are recorded from this island, of which M. inceptum Morek, Suzuki, Schill, Georgiev, Yankova, Marley et Michalczyk, 2019 is new for the fauna of Russia. New data were obtained on the distribution and genetic diversity of M. tardigradum Doyère, 1840. The third species, Milnesium sp., is similar to M. tardigradum but differs from latter in the presence of a characteristic thickened cuticle zone at the base of the claws of the fourth pair of legs and is probably a new for science species.

Ontogeny of the redlichiid trilobite Metaredlichia cylindrica from the lower Cambrian (Stage 3) of South China

2012 ◽  
Vol 86 (4) ◽  
pp. 646-651 ◽  
Author(s):  
Tao Dai ◽  
Xingliang Zhang
Keyword(s):  
Black Shale ◽  
South China ◽  
Lower Cambrian ◽  
Morphological Changes ◽  
Hubei Province ◽  
Early Cambrian ◽  
Developmental Trends ◽  
Ontogenetic Stages ◽  
Two Stages ◽  
Fourth Pair

A number of immature and mature exoskeletons allow the first detailed description of the ontogeny of the early Cambrian redlichiid trilobite Metaredlichia cylindrica, from black shale of the Shuijingtuo Formation in Hubei Province, South China. The material includes numerous complete protaspides, within which two stages can be differentiated according to the appearance of a shallow furrow that separates the protopygidial area from the protocranidium. Also, identification of the subsequent ontogenetic stages, including meraspides and holaspides, depends on isolated cranidia that display prominent morphological changes such as the contraction of frontal glabellar lobe, appearance of the fourth pair of glabellar furrows, and modification of the facial suture from proparian to opisthoparian. Incorporating the whole ontogenetic sequence allows us not only to trace the developmental trends of various structures with growth, but also to assign the protaspides to their adults correctly, particularly with the help of meraspid specimens.

LINKAGE GROUP IV OF TRIBOLIUM CASTANEUM

1972 ◽  
Vol 14 (3) ◽  
pp. 675-680 ◽  
Author(s):  
Peter S. Dawson
Keyword(s):  
Linkage Group ◽  
Tribolium Castaneum ◽  
Group Iv ◽  
Eye Color ◽  
Flour Beetle ◽  
Color Mutant ◽  
White Locus ◽  
Fourth Pair

A new recessive eye color mutant, hazel, of the flour beetle, Tribolium castaneum, has been mapped in linkage group IV near the white locus, thus establishing the existence of a fourth pair of closely linked eye color genes in this species. A revision of linkage group IV is proposed.

Effect of Extrinsic Rearfoot Post Design on the Lateral-to-Medial Position and Velocity of the Center of Pressure

2006 ◽  
Vol 96 (5) ◽  
pp. 383-392 ◽  
Author(s):  
Joanne S. Paton ◽  
Simon K. Spooner
Keyword(s):  
Center Of Pressure ◽  
Foot Orthoses ◽  
Experimental Conditions ◽  
Period Data ◽  
Fourth Pair ◽  
Center Of Pressure Velocity

Findings from investigations of the effects of external forefoot and rearfoot posts added to foot orthoses have been inconclusive. This study was undertaken to examine the effects of rearfoot post design on the lateral-to-medial position and velocity of the center-of-pressure path. Four identical pairs of neutral-cast polypropylene orthotic shells were constructed; three pairs had a rearfoot post of specified design added. The fourth pair, the control, did not have a post added. Stance period data were broken down into four functional phases, and the statistically significant differences between the experimental conditions were calculated and analyzed. The addition of a rearfoot post to an orthotic shell affects center-of-pressure lateral-to-medial position and velocity. Although the effect of the post designs seemed to provide reasonably predictable changes in center-of-pressure position, the effect on center-of-pressure velocity was variable and inconsistent. The effect of the orthotic post was dependent on design and phase of gait. The addition of a rearfoot post and, specifically, the design of the post can probably be used to alter the center-of-pressure position and velocity. (J Am Podiatr Med Assoc 96(5): 383–392, 2006)

V.—Woodwardian Museum Notes

1896 ◽  
Vol 3 (4) ◽  
pp. 161-166
Author(s):  
F. R. Cowper Reed
Keyword(s):  
The Third ◽  
Stage Of Development ◽  
Last Stage ◽  
Fourth Pair

A Long the branch which is marked earlier by Cyrtometopus and Cheirurus (sens. str.), the last stage of development corresponds with Salter's subgenus Crotalocephalus. This is almost entirely restricted to Devonian beds, but it is linked to Cheirurus (sens. str.) in time and zoological characters by Ch. Sternbergi (Boeck) and Ch. Quenstedti (Barr.), in which the glabellar side-furrows hardly meet in the middle of the glabella. The important subgeneric characters of Crotalocephalus are the continuous first and second side-furrows, the triangular basal lobes which nearly or quite meet in the centre of the glabella at their apices, and the nearly straight obliquely-directed third side-furrows of the glabella. The earlier forms of the subgenus have their triangular basal lobes still separated by a median portion of the glabella, as in Ch. Quenstedti, from Étage E. This species has a rather curiously specialized kind of pygidium, with only two pairs of long spinose pleuræ the third pair is very short and rudimentary, and of the fourth pair there is no trace. It is a noteworthy point that the pygidia of this subgenus are, as a rule, almost identical with those in the group of Cheirurus (sens. str.), with three equal pleuræ with free ends (vide antea), and do not show the enlargement of the first pair, as in the Russian Cheirurus (sens. str.).

Lacking sensory (rather than locomotive) legs affects locomotion but not food detection in the harvestman Holmbergiana weyenberghi

2013 ◽  
Vol 91 (10) ◽  
pp. 726-731 ◽  
Author(s):  
I. Escalante ◽  
A. Albín ◽  
A. Aisenberg
Keyword(s):  
Substrate Recognition ◽  
Subtropical Forest ◽  
Agonistic Interactions ◽  
Field Surveys ◽  
Food Detection ◽  
Detection Speed ◽  
Fourth Pair

The ability to release a leg when forced by predators or during agonistic interactions is widespread and frequent in arthropods. Despite immediate benefits, losing legs may affect locomotion, sensory performance, reproduction, and fitness. The costs of autospasy in arachnids have been scarcely addressed. Therefore, we tested the hypothesis that the number and type of self-amputated legs (sensory or locomotive) affect locomotion and food detection speeds in the harvestman Holmbergiana weyenberghi (Holmberg, 1876) (Sclerosomatidae). With field surveys in a subtropical forest in Uruguay we found that 35% of individuals lacked at least one leg, and sensory legs (second pair) were the most frequently lost. In an indoor setup, we found that individuals missing one sensory leg walked and climbed a trunk slower than individuals lacking a locomotive leg (first, third, or fourth pair), or compared with those with eight legs. Lacking legs did not affect the food detection speed. Additionally, larger individuals with eight legs had greater walking and climbing speeds. Therefore, losing sensory legs affects locomotion in these harvestmen and may confer costs in orientation, balance, and substrate recognition. Finally, we compared our results with the different patterns reported for the effect of autospacy in other harvestman species.

The Jumping Mechanism of Salticid Spiders

1959 ◽  
Vol 36 (4) ◽  
pp. 654-664 ◽  
Author(s):  
D. A. PARRY ◽  
R. H. J. BROWN
Keyword(s):  
Direct Evidence ◽  
Jumping Spider ◽  
Multiple Image ◽  
Extensor Muscles ◽  
The Moment ◽  
Salticid Spiders ◽  
Fourth Pair

1. Photographs of the jumping spider Sitticus pubescens (Salticidae) show that the jump is almost entirely due to the sudden straightening of the fourth pair of legs. Multiple-image photographs show the importance of a silk drag-line in controlling the jump. 2. The torques at the leg joints have been estimated. Extension torques occur at the two hinge joints although these lack extensor muscles. 3. The erection of leg spines at the moment of the jump provides direct evidence that hydraulic forces are involved in the jump. This view is supported by estimates of the pressures involved, which fall within a factor of about two of those previously measured in the legs of the spider Tegenaria.

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