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25355. Wenyonia gracilis sp. n. (Cestoda: Caryophyllidea) from Synodontis zambezensis (Siluriformes: Mochokidae): the first native caryophyllidean tapeworm from southern Africa

Creator:
Schaeffner, Bjoern C, Rooyen, Divan van, Gerber, Ruan, Scholz, Tomáš, and Smit, Nico J
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
tasemnice, biodiverzita, biogeografie, tapeworms, biodiversity, biogeography, Afrika jižní, Africa, Southern, fish parasites, new species, molecular characterisation, taxonomy, 2, and 59
Language:
English
Description:
Parasitological examination of freshwater fishes of the Phongolo River in north-eastern KwaZulu-Natal, South Africa resulted in the discovery and morphological and molecular characterisation of a new species of Wenyonia Woodland, 1923 (Cestoda: Caryophyllidea). The new species from the plain squeaker, Synodontis zambezensis Peters (Siluriformes: Mochokidae), is morphologically most similar to Wenyonia acuminata Woodland, 1923, a species reported from three species of Synodontis in north-eastern, western and central Africa (Sudan, Nigeria, Democratic Republic of the Congo). Both these species are markedly different from congeners by having a nematoform body and a digitiform scolex. Wenyonia gracilis sp. n. differs from W. acuminata in its general body size, length and width of main body regions (testicular and uterine regions), a posterior extension of the testes into the uterine region, numerous postovarian vitelline follicles filling the entire medulla, eggs c. 1/3 larger in size, and a scolex with an apical introvert but devoid of longitudinal furrows and a well-defined base. Wenyonia gracilis is the seventh species in the genus and the first autochthonous caryophyllidean ever reported and described from southern Africa (south of the Zambezi River)., Bjoern C. Schaeffner, Divan van Rooyen, Ruan Gerber, Tomáš Scholz, Nico J. Smit., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

25356. Werner Heisenberg, Niels Bohr a příběh kodaňské interpretace

Creator:
Filip Grygar
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Bohr, Niels, 1885-1962, Heisenberg, Werner, 1901-1976, kvantová teorie, quantum theory, Copenhagen Interpretation, Complementarity, 12, and 00
Language:
Czech
Description:
Příspěvek se zaměřuje na zavádějící příběh o tzv. kodaňské interpretaci kvantové mechaniky, již jako údajně nerozpornou či jednotnou vytvořili a sdíleli na základě tzv. kodaňského ducha kvantové teorie její tvůrci v roce 1927. Článek bude vycházet z role, kterou v tomto příběhu sehráli především dva významní fyzikové N. Bohra W. Heisenberg. První část příspěvku seznamuje s variacemi toho, co se v literatuře považuje za kodaňskou interpretaci. Druhá část odhaluje, že zatímco kvantová mechanika vznikla ve dvacátých letech 20. století, kodaňská interpretace je veskrze problematickým a především Heisenbergovým produktem z let padesátých. Jednou z hlavních motivací, kvůli níž vystoupil s tzv. kodaňskou interpretací, byla obrana vůči množícím se kritikám obhájců kvantové teorie. Jelikož mezi členy tzv. kodaňské školy nepanovala žádná jednotná či nerozporná interpretace kvantové mechaniky, zaměřuje se poslední část příspěvku na několik vybraných rozdílů hlavně mezi Bohrovým a Heisenbergovým výkladem kvantové teorie., The article focuses on the misleading story of the so-called Copenhagen interpretation of quantum mechanics. The interpretation was allegedly created as unitary or consistent and shared by its founders in 1927 by virtue of the so-called Copenhagen spirit of quantum theory. The paper is based on the role which two leading figures, Niels Bohr and Werner Heisenberg, played in this story. The first part of the article introduces variations of what is considered to be Copenhagen interpretation. The second part reveals that while quantum mechanics had originated in the 1920s, the Copenhagen interpretation was mainly a problematic Heisenberg’s product of the 1950s. One of his main motivations for the introduction of Copenhagen interpretation was to set up a defence against increasing criticism of the supporters of quantum theory. Since there was no unitary or consistent interpretation of quantum mechanics among members of the so-called Copenhagen school, the last part of the paper focuses on several differences primarily between Bohr and Heisenberg’s interpretation., Filip Grygar., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

25358. What are quantasomes? The background of a nearly forgotten term

Creator:
Ball, R., Richter, M., and Wild, A.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
After the formulation of the photosynthetic unit (PSU) concerning the cooperation of 2400 chlorophyll molecules in the reduction of one molecule of C02 by Emerson and Arnold in 1932, the search for a morphological expression of the functional unit began. The quantasome hypothesis is an attempt to relate the structure visible in the electron microscope, the quantasome, and the PSU. The term 'quantasome' was introduced by Park and Calvin as a name for grana subunits. The quantasomes were regarded as the main integral parts of the grana lamellae in the protein lipid layers. Yet it soon became clear that a morphological mit such as the quantasomes did not exist. Nevertheless, the term was still used in various applications till the eighties.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

25359. What is the role body sway deviation and body sway velocity play in postural stability in older adults

Creator:
Jančová Všetečková, Jitka and Drey, Nicholas
Format:
print, text, and regular print
Type:
model:article, article, Text, časopisecké články, práce podpořená grantem, and TEXT
Subject:
věkové faktory, staří, staří nad 80 let, průřezové studie, ženské pohlaví, lidé, kinestezie--fyziologie, mužské pohlaví, lidé středního věku, pohybová aktivita, posturální rovnováha--fyziologie, and sociální chování
Language:
English
Description:
This cross sectional study focused on how Postural Stability (PS) indicators: body sway deviation (BSD) and body sway velocity (BSV), change with age and their association with levels of social and physical activity. Observational study: 80 older adults (aged: 60-96) were purposefully recruited from two sources: the University of the Third Age (TAU) (n = 35) and a residential care home (CH) (n = 45). Differences in the indicators of PS, approximated through Centre of Pressure (COP) measurements, were assessed by the Romberg Stance Test (Test A) subsequently repeated on 10 cm foam surface (Test B), using a Kistler Dynamometric Platform. The RCH Group was older, had higher BMI and was less socially and physically active, showed more body sway in all indicators compared to TAU group. For all participants body sway velocity (BSV) was significantly correlated with age. The strength of correlation of body sway deviation (BSD) with age was also significant but not as strong. The findings indicate in line with previous studies that deterioration in BSV is associated with poor PS more than deterioration in BSD. and J. Jančová Všetečková, N. Drey
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

25360. What is the role of neurotransmitter systems in cortical seizures?

Creator:
Pavel Mareš and Hana Kubová
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, neurofyziologie, epileptologie, farmakologie, neurophysiology, epileptology, pharmacology, cortical epileptic afterdischarges, GABA, glutamate, immature rats, 14, and 612
Language:
English
Description:
Epileptic afterdischarges (ADs) elicited by electrical stimulation of sensorimotor cortical area were used as a model to study the role of neurotransmitter systems in cortical seizures in three age groups of developing rats. Drugs augmenting inhibition mediated by GABAA receptors were found to suppress ADs in all age groups, their activity was usually more marked in younger than in 25-day-old rat pups. Drugs potentiating GABAB receptors exhibit lower efficacy and more complicated developmental profile than GABAA-ergic drugs. Effects of an antagonist of GABAB receptor – marked prolongation of ADs in all three age groups – suggest an important role of GABAB receptors in arrest of cortical seizures. Drugs affecting glutamate receptors exhibit variable effects, usually better expressed in older animals than in 12-day-old ones. No specific role for ionotropic as well as metabotropic glutamate receptors could be predicted. Activation of adenosinergic inhibitory modulatory system also exhibited anticonvulsant action in the present model. All three neurotransmitter systems probably participate in mechanisms of generation, maintenance and arrest of cortical seizures., P. Mareš, H. Kubová., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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