scholarly journals Anterior Part of the Calcarine Fissure

2020 ◽  
Author(s):  
Author(s):  
Len Wen-Yung ◽  
Mei-Jung Lin

Four cone-shaped rectal papillae locate at the anterior part of the rectum in Dacus dorsalis fly. The circular base of the papilla protrudes into the haemolymph (Fig. 1,2) and the rest cone-shaped tip (Fig. 2) inserts in the rectal lumen. The base is surrounded with the cuticle (Fig. 5). The internal structure of the rectal papilla (Fig. 3) comprises of the cortex with the columnar epithelial cells and a rod-shaped medulla. Between them, there is the infundibular space and many trabeculae connect each other. Several tracheae insert into the papilla through the top of the medulla, then run into the cortical epithelium and locate in the intercellular space. The intercellular sinuses distribute in the posterior part of the rectal papilla.The cortex of the base divides into about thirty segments. Between segments there is a radial cell (Fig. 4). Under the cuticle, the apical cell membrane of the cortical epithelium is folded into a regular border of leaflets (Fig. 5).


2020 ◽  
Vol 29 (1) ◽  
pp. 138-154
Author(s):  
R.V. Smirnov ◽  
O.V. Zaitseva ◽  
A.A. Vedenin

A new species of Pogonophora obtained from one station at a depth of 25 m from near the Dikson Island in the Kara Sea is described. Galathealinum karaense sp. nov. is one of the largest pogonophorans, the first known representative of the rare genus Galathealinum Kirkegaard, 1956 in the Eurasian part of the Arctic Ocean and a highly unusual finding for the desalted shallow of the Yenisey Gulf. Several characters occurring in the new species are rare or unique among the congeners: under-developed, hardly discernible frills on the tube segments, extremely thin felted fibres in the external layer of the tube, and very faintly separated papillae in the anterior part of the trunk. Morphological characters useful in distinguishing species within the genus Galathealinum are defined and summarised in a table. Diagnosis of the genus Galathealinum is emended and supplemented by new characters. Additionally, three taxonomic keys are provided to the species of Galathealinum and to the known species of the Arctic pogonophorans using either animals or their empty tubes only, with the brief zoogeographical information on each Arctic species.


Author(s):  
S.A. Moiseev

The question of physiological function variability is of great theoretical interest, since it is a part of the theory of human voluntary movement control. The skeletal muscle control system should probably have a mechanism to reduce or limit the range of its possible variations. Presumably, the organization of the motor system elements according to the principle of muscular synergy is of such a nature. The objective of the work is to study variations and signs of the coordinated bioelectric activity of skeletal muscles in one of the resulting archery phases. Materials and Methods. The study enrolled 5 highly qualified sportsmen (Master of Sport, International Master of Sport). Archers shot 10 series of 3 shots, target distance 18 m, indoors. Simultaneous recording of electrical activity of 12 skeletal muscles of the upper limb girdle and a 3D video sequence was made. The authors analyzed indicators of distribution, descriptive and variation statistics for grouped data. Multiple regression analysis was used to identify signs of consistent muscle activity. Results. Variability magnitudes, characterized by statistical parameters, established for the turn-off-peak characteristics of various muscles, did not have an explicit dependence. Muscles with relatively high scattering parameters in terms of the EMG average amplitude could have a small variation in the average number of EMG turns. The radial flexor of the left hand wrist was a part of muscular synergy in 90 % of cases, the anterior part of the left limb deltoid muscle – in 80 % of cases, the lower and upper beams of the right and left cowl muscle – in 70 % of cases. Other muscles under consideration were their part in less than 60 % of cases. Conclusion. The system of skeletal muscles that are actively involved in the resulting phases of precision movement can be controlled according to the mechanism of functional synergy formation, which probably helps to reduce the range of possible variations in the parameters of muscle electroactivity. Keywords: variability, archery, electromyography, coordination structure, muscle synergy. Вопрос вариативности физиологических функций представляет интерес в теоретическом плане, поскольку является частью теории управления произвольными движениями человека. Система управления скелетными мышцами, вероятно, должна иметь механизм, позволяющий сократить или ограничить диапазон возможных ее вариаций. Таковым, предположительно, является организация элементов моторной системы по принципу мышечных синергий. Цель работы – изучение вариаций и признаков согласованной биоэлектрической активности скелетных мышц в одной из результирующих фаз выстрела из лука. Материалы и методы. В исследованиях приняли участие 5 высококвалифицированных спортсменов (МС, МСМК). Лучники выполняли 10 серий по 3 выстрела с дистанции 18 м в крытом помещении. Производилась синхронная регистрация электрической активности 12 скелетных мышц верхнего плечевого пояса и 3D-видеоряда. Анализировались показатели распределения, описательной и вариационной статистики для сгруппированных данных. Для выявления признаков согласованной активности мышц применялся множественный регрессионный анализ. Результаты. Величины вариативности, характеризуемые статистическими параметрами, установленные для турн-аплитудных характеристик различных мышц, не имели явной зависимости. Мышцы, имеющие относительно высокие параметры разброса значений по показателю средней амплитуды ЭМГ, могли иметь небольшую вариативность среднего числа турнов ЭМГ. Лучевой сгибатель кисти левой руки являлся частью мышечной синергии в 90 % случаев, передняя часть дельтовидной мышцы левой конечности – в 80 %, нижние и верхние пучки трапециевидной мышцы правой и левой сторон – в 70 %. Другие исследуемые мышцы являлись их частью в менее чем 60 % случаев. Выводы. Управление системой скелетных мышц, принимающих активное участие в реализации одной из результирующих фаз точностного движения, может осуществляться по механизму образования функциональных синергий, что, вероятно, способствует снижению диапазона возможных вариаций параметров электроактивности мышц. Ключевые слова: вариативность, стрельба из лука, электромиография, координационная структура, мышечные синергии.


MedAlliance ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 61-68

The pectoralis major is a widely used muscle in reconstruction surgery for replacement soft tissue defects of a head, neck, thorax, upper limbs and restoration of muscle active function. The peculiarities of anatomy of the pectoralis major makes it possible to divide the muscle into several segments with their own innervations and supply and use them independently from each other. This article describes the anatomy of the pectoralis major and the opportunity for clinical applications of different segments of this muscle. The authors demonstrate the result of the restoration of shoulder and elbow flexion in a patient with arthrogryposis due to simultaneous transfer of the proximal part of pectoralis major to the anterior part of the deltoid muscle and the distal part of pectoralis major to the biceps with good functional results. The article will be useful for plastic surgeons, orthopedic surgeons and physiotherapists.


2017 ◽  
Vol 4 (12) ◽  
pp. 171288 ◽  
Author(s):  
Alexander L. Vereshchaka ◽  
Anastasia A. Lunina ◽  
Jørgen Olesen

Species within Gennadas differ from each other largely only in male (petasma) and female (thelycum) copulatory characters, which were restudied in scanning electron microscopy and used as a basis for phylogenetic analyses. Twenty-six petasma characters and 49 thelycum characters were identified. All 16 recognized species of Gennadas and Aristaeomorpha foliacea (outgroup) were included as terminals. Four robust monophyletic clades were retrieved, described and diagnosed as new species groups. The thelycum characters had greater impact on tree topology and supported deeper nodes than did the petasma characters. We hypothesize that features of the thelycum evolved first followed by aspects of the petasma. Relatively more conservative characters include parts of the sternites of the thelycum and of the petasma, while the scuti and protuberances on the thelycum and the shape and subdivisions of the petasma lobes are evolutionarily plastic. We identified two groups of copulatory characters, which are likely coupled functionally and interlinked evolutionarily: (i) the external part of the petasma and the posterior part of the thelycum and (ii) the internal part of the petasma and anterior part of the thelycum. We reconstruct possible mating position during copulation for each of the new species groups presented here. We also present an updated key to genera of Benthesicymidae and key to species of Gennadas .


The author commences his paper by making some observations on the general arrangements of the ossicula auditûs . The malleus and incus being firmly connected together by ligaments, are considered as a single bone, forming an elastic arch, the anterior extremity of which is firmly attached to the Glasserian fissure, the posterior to the anterior part of the mastoid cells. This arch is kept steady by the actions of the tensor tympani. The movement of this arch is that of rotation; and it is effected by the tensor tympani muscle. When this muscle contracts, the lower part of the arch, consisting of the handle of the malleus and the long process of the incus, is drawn inwards; by this action the membrana tympani is rendered tense, and the stapes being pressed towards the cavity of the labyrinth, the fluid in the latter is compressed.


1977 ◽  
Vol 47 (1) ◽  
pp. 50-56 ◽  
Author(s):  
Hiroshi Matsumura ◽  
Yasumasa Makita ◽  
Kuniyuki Someda ◽  
Akinori Kondo

✓ We have operated on 12 of 14 cases of arteriovenous malformation (AVM) in the posterior fossa since 1968, with one death. The lesions were in the cerebellum in 10 cases (three anteromedial, one central, three lateral, and three posteromedial), and in the cerebellopontine angle in two; in two cases the lesions were directly related to the brain stem. The AVM's in the anterior part of the cerebellum were operated on through a transtentorial occipital approach.


1976 ◽  
Vol 69 (1) ◽  
pp. 106-125 ◽  
Author(s):  
D L Brown ◽  
A Massalski ◽  
R Patenaude

The organization of microtubular systems in the quadriflagellate unicell Polytomella agilis has been reconstructed by electron microscopy of serial sections, and the overall arrangement confirmed by immunofluorescent staining using antiserum directed against chick brain tubulin. The basal bodies of the four flagella are shown to be linked in two pairs of short fibers. Light microscopy of swimming cells indicates that the flagella beat in two synchronous pairs, with each pair exhibiting a breast-stroke-like motion. Two structurally distinct flagellar rootlets, one consisting of four microtubules in a 3 over 1 pattern and the other of a striated fiber over two microtubules, terminate between adjacent basal bodies. These rootlets diverge from the basal body region and extend toward the cell posterior, passing just beneath the plasma membrane. Near the anterior part of the cell, all eight rootlets serve as attachment sites for large numbers of cytoplasmic microtubules which occur in a single row around the circumference of the cell and closely parallel the cell shape. It is suggested that the flagellar rootless may function in controlling the patterning and the direction of cytoplasmic microtubule assembly. The occurrence of similar rootlet structures in other flagellates is briefly reviewed.


1991 ◽  
Vol 82 (2) ◽  
pp. 143-181 ◽  
Author(s):  
Lars Ramsköld

ABSTRACTThe systematics of parts of the Odontopleuridae are revised using character analyses tracing homologous structures, and a computerised cladistic analysis. The choice of outgroup is shown to affect the result of the analysis. Several synapomorphies place Selenopeltis, the type genus of the Selenopeltinae Hawle & Corda, 1847 as sister genus to Dicranurus. The latter's close relationship to Miraspis, type genus of the Miraspidinae Richter & Richter, 1917 is confirmed. The Selenopeltinae therefore becomes a senior subjective synonym of the Miraspidinae. The Selenopeltinae includes about 90 of the over 380 named odontopleurid species known to date (excluding accepted synonyms). The Ceratocephalinae is recognised, including about 30 species. The paired, large pygidial border spines present in most odontopleurids are in some species not homologous, and a falsifiable hypothesis is proposed for the homology of the ‘true major border spines’. This structure is the posterior pleural spine of the tenth postcephalic segment in selenopeltines, ceratocephalines and odontopleurines, and in acidaspidines and apianurines it is the serially homologous spine of the eleventh postcephalic segment. The spine belongs to the first pygidial segment in all taxa except ceratocephalines, where it is on the last thoracic segment. The homology in selenopeltines of the progressive restructuring of the cheek border is reviewed, explaining the supramarginal appearance of the genal spine. The presence and homology of the sublobation of L1 in odontopleurids is discussed, and it may be homologous with the sublobation in lichids. The strongly differentiated thoracic segmental lengths (exsag.), with maximum length reached in the anterior part of thorax, and the much reduced length of the posterior segments, are aspects of a single character-complex, uniquely derived within the Selenopeltinae. The ontogenetic origin of the anterior and posterior pleural spines is reviewed. The presence in Ceratocephala of two instars in one meraspid degree is discussed. A cladistic analysis of selenopeltine and ceratocephaline genera does not entirely resolve the topology of the phylogenetic tree of these taxa, but it confirms Selenopeltis as sister taxon to Dicranurus. These two genera belong in a clade also including Miraspis, Selenopeltoides, and Ceratonurus. Two new genera are erected, Ceratocara and Archaeopleura, the latter with type species A. kazakhensis sp. nov.


Sign in / Sign up

Export Citation Format

Share Document