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12. Lion-tailed macaques show a stable direction and reinforcement of hand preference in simple reaching tasks over several years
- Creator:
- Kuběnová, Barbora, Lhota, Stanislav, Tomanová, Veronika, Blažek, Vladimír, and Konečná, Martina
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- handedness, hand use, laterality, unimanual behaviour, and Macaca silenus
- Language:
- English
- Description:
- Research on hand preference in non-human primates provides information about the evolutionary origin of population-level bias of human handedness. Human hand preference has been shown to remain stable throughout an individual's lifespan. However, the stability of hand preference and its change with age in non-human primates remains questionable. We recorded hand use in lion-tailed macaques (Macaca silenus) during simple reaching tasks in three time periods over six years. We tested the effect of age and body posture on the direction and strength of hand preference in 23 observed individuals. In a subsample of 13 individuals followed for two or three subsequent time periods, we assessed the stability of hand preference across study periods. The direction of hand preference was highly stable; we detected no individuals changing from a left- to right-, or right- to left- preference and repeated quantitative measures of hand preference were correlated among subsequent study periods. Hand preference was, however, reinforced in older individuals and an individual's hand preference was stronger in postures with both hands free for foraging. Stable hand preference at an individual level, and its reinforcement over an individual's lifetime, is emerging as a robust finding across the primate order.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
13. Mildly (1, 2)∗ -normal spaces and some bitopological functions
- Creator:
- Kayathri, K., Ravi, O., Thivagar, M. L., and Joseph Israel, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- mildly (1, 2)∗ -normal space, (1, 2)∗ -rg-closed set, (1, 2)∗ -rg-continuous function, almost (1, 2)∗ -continuous function, and almost (1, 2)∗ -rg-closed function
- Language:
- English
- Description:
- The aim of the paper is to introduce and study a new class of spaces called mildly (1, 2)∗ -normal spaces and a new class of functions called (1, 2)∗ -rg-continuous, (1, 2)∗ - R-map, almost (1, 2)∗ -continuous function and almost (1, 2)∗ -rg-closed function in bitopological spaces. Subsequently, the relationships between mildly (1, 2)∗ -normal spaces and the new bitopological functions are investigated. Moreover, we obtain characterizations of mildly (1, 2)∗ -normal spaces, properties of the new bitopological functions and preservation theorems for mildly (1, 2)∗ -normal spaces in bitopological spacesThe aim of the paper is to introduce and study a new class of spaces called mildly (1, 2)∗ -normal spaces and a new class of functions called (1, 2)∗ -rg-continuous, (1, 2)∗ - R-map, almost (1, 2)∗ -continuous function and almost (1, 2)∗ -rg-closed function in bitopological spaces. Subsequently, the relationships between mildly (1, 2)∗ -normal spaces and the new bitopological functions are investigated. Moreover, we obtain characterizations of mildly (1, 2)∗ -normal spaces, properties of the new bitopological functions and preservation theorems for mildly (1, 2)∗ -normal spaces in bitopological spaces.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14. Molecular and morphological characterisation of the metacercariae of two species of Cardiocephaloides (Digenea: Strigeidae) infecting endemic South African klipfish (Perciformes: Clinidae)
- Creator:
- Vermaak, Anja, Smit, Nico J., and Kudlai, Olena
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Trematoda, Clinus superciliosus, Clinus cottoides, marine fish parasites, DNA, and morphology
- Language:
- English
- Description:
- South African clinids are a major component of the temperate intertidal regions that are also known to participate in life cycles and transmission of several groups of parasites. However, the knowledge of trematode diversity of these fishes is incomplete. In this study, two species of Clinus Cuvier, the super klipfish Clinus superciliosus (Linnaeus) and the bluntnose klipfish Clinus cottoides Valenciennes, were collected from six localities along the South African coast and examined for the presence of trematodes. Metacercariae of Cardiocephaloides Sudarikov, 1959 were found in the eye vitreous humour and brain of C. superciliosus and in the eye vitreous humour of C. cottoides. Detailed analyses integrating morphological and molecular sequence data (28S rDNA, ITS2 rDNA-region, and COI mtDNA) revealed that these belong to two species, Cardiocephaloides physalis (Lutz, 1926) and an unknown species of Cardiocephaloides. This study provides the first report of clinid fishes serving as intermediate hosts for trematodes, reveals that the diversity of Cardiocephaloides in South Africa is higher than previously recorded, and highlights the need for further research to elucidate the life cycles of these trematode species. The broad geographical distribution of Cardiocephaloides spp. was confirmed in the present study based on molecular sequence data. The host-parasite interactions between clinid fishes and metacercariae of Cardiocephaloides are yet to be explored.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15. Morphological and molecular data for three species of the Microphallidae (Trematoda: Digenea) in Australia, including the first descriptions of the cercariae of Maritrema brevisacciferum Shimazu et Pearson, 1991 and Microphallus minutus Johnston, 1948
- Creator:
- Kudlai, Olena, Cutmore, Scott C, and Cribb, Thomas H
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- morfologie (biologie), sladké vody, morphology (biology), freshwater, larval stages, life cycle, rDNA sequences, Brisbane River, 2, and 59
- Language:
- English
- Description:
- Cercariae and metacercariae of three species of the Microphallidae Travassos, 1920 were found in snails and crustaceans from tributaries of the Brisbane River, Queensland, Australia. Specimens of Maritrema brevisacciferum Shimazu et Pearson, 1991 and Microphallus minutus Johnston, 1948, which have previously been reported in Queensland, were found as cercariae in the tateid gastropod Posticobia brazieri (Smith) and as metacercariae of M. brevisacciferum in the atyid shrimp Caridina indistincta Calman and of M. minutus in the parastacid crayfish Cherax dispar Reik. Combined analysis of morphological and molecular data, based on newly generated ITS2 and partial 28S rDNA data, linked cercariae and metacercariae for both species. This is the first report of the first intermediate hosts of M. brevisacciferum and M. minutus. Infections of another unidentified microphallid metacercariae, Microphallidae gen. sp., were found in P. brazieri and C. indistincta. The sequences of metacercarial isolates from both hosts were identical. The data on the Microphallidae from Australia and species that develop in freshwater invertebrates were examined in detail., Olena Kudlai, Scott C. Cutmore, Thomas H. Cribb., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
16. m∗-fuzzy basically disconnected spaces in smooth fuzzy topological spaces
- Creator:
- Amudhambigai, B., Uma, Mallasamudram Kuppusamy, and Roja, Elango
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- m∗ r-fuzzy ˜g-open Fσ set, m∗ -fuzzy basically disconnected space, and m∗ r-fuzzy open function
- Language:
- English
- Description:
- In this paper, the concepts of m∗ r-fuzzy ˜g-open Fσ sets and m∗ -fuzzy basically disconnected spaces are introduced in the sense of Šostak and Ramadan. Some interesting properties and characterizations are studied. Tietze extension theorem for m∗ -fuzzy basically disconnected spaces is discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17. New species of Guidus Ivanov, 2006 (Cestoda: Phyllobothriidea) from Bathyraja magellanica (Philippi) from the Patagonian Continental Shelf of Argentina
- Creator:
- Menoret, Adriana and Ivanov, Verónica A.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Guidus francoi sp. n., Guidus magellanicus sp. n., morphology, description, SEM, Magellan skate, Arhynchobatidae, Argentinian Continental Shelf, and Southwestern Atlantic Ocean
- Language:
- English
- Description:
- Specimens representing two new species of Guidus Ivanov, 2006 were collected from the Magellan skate (Bathyraja magellanica [Philippi]) in the Patagonian Continental Shelf of Argentina, Southwestern Atlantic Ocean. Guidus francoi sp. n. and Guidus magellanicus sp. n. differ from their congeners by a particular combination of features, including type of bothridia, worm length, number of testes, and distribution of vitelline follicles. Guidus francoi sp. n. is distinguished from G. magellanicus sp. n. by having fewer proglottids, fewer testes and a higher ratio between the cirrus sac length and the proglottid width. The microthrix pattern of species of Guidus from the Southwestern Atlantic is described, based on specimens of G. francoi sp. n., Guidus magellanicus sp. n., and newly collected specimens of Guidus argentinense Ivanov, 2006. These three species share the presence of wide aristate gladiate spinitriches on the proximal bothridial surface, narrow gladiate spinitriches on the bothridial rim, and filitriches on the distal bothridial surface. The diagnosis of Guidus is revised to include several features exhibited by the new species (i.e., presence of bothridial indentations and bothridial stalks, distribution of vitelline follicles, and eggs grouped in cocoons). The discovery of G. francoi sp. n. and G. magellanicus sp. n. from B. magellanica increases the number of species of Guidus collected from batoids in the Southwestern Atlantic from one to three. The specificity exhibited by the species herein described reinforces the tight association between rays in the genera Guidus and Bathyraja.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
18. Occurrence and diversity of anaerobic gut fungi in wild forest elephants and buffaloes inhabiting two separated forest ecosystems in Central West Africa
- Creator:
- Schulz, Doreen, Pšenková-Profousová, Ilona, Červená, Barbora, Procter, Miranda, Fuh Neba, Terence, Modrý, David, Petrželková, Klára J., and Qablan, Moneeb A.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- gut microbiome, mycobiome, wild herbivores, and Neocallimastigomycetes
- Language:
- English
- Description:
- Anaerobic gut fungi of the class Neocallimastigomycetes are of great importance for herbivorous animals. Their immediate colonization and mechanical breakdown of plant particles pave the way for highly efficient enzymatic fermentation of complex plant polysaccharides. Neocallimastigomycetes are found in a variety of herbivores, yet so far studies almost exclusively investigated domestic or captive animals. Here, the occurrence and diversity of Neocallimastigomycetes in two different populations of sympatric, wild African forest elephants and forest buffaloes were determined. In both hosts together, a total of 16 species-equivalent Operational Taxonomic Units (OTUs) (0.05 cut-off level) were generated. Buffaloes harboured four and elephants five anaerobic fungi genera or genus-equivalent taxa, respectively, with four genera occurring in both hosts. In elephants the majority of gut fungi group within a cluster of yet unknown Neocallimastigomycetes. Similarly, some anaerobic fungi found in buffaloes form a genus-equivalent cluster with likewise undescribed gut fungi. Sequences grouping in these two clusters could potentially qualify as representatives of new anaerobic fungi genera. Further, three sequences have not yet been encountered in any study and cannot be assigned to any genus or genus-equivalent Neocallimastigomycetes taxon. Whether these sequences also represent putative new lineages needs further investigation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
19. Osteological description of Indian lepidophagous catfish Pachypterus khavalchor (Siluriformes: Horabagridae) from the Western Ghats of India
- Creator:
- Pise, Manoj, Gosavi, Sachin M., Gorule, Pankaj A., Verma, Chandani R., Kharat, Sanjay S., Kalous, Lukáš, and Kumkar, Pradeep
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- skeletal morphology, lepidophagy, sexual dimorphism, and systematics
- Language:
- English
- Description:
- The present study provides a comprehensive osteological description of Pachypterus khavalchor from the family Horabagridae. Nine individuals of P. khavalchor representing both males and females collected from the type locality were cleared and double-stained to provide a description of osteological characteristics. The presence of an almost straight dorsal roof to the cranium, a long and protruding premaxilla with numerous rows of tiny, villiform teeth, a spoon-like lower jaw with villiform teeth projecting outward, and five long and ossified ceratobranchials, with the 5th ceratobranchial containing a set of 80 to 90 conical teeth, sheds light on the ecomorphological adaptation in P. khavalchor that may have led to the evolution of lepidophagy. Furthermore, a slight difference in the structure of the complex hypurapophysis was observed between males and females. The information on the osteology of the Khavalchor catfish forms a baseline for taxonomic research of the entire Horabagridae family comprising four genera with ten species distributed in Asia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
20. Polarisation of human macrophages towards an M1 subtype triggered by an atypical Brazilian strain of Toxoplasma gondii results in a reduction in parasite burden
- Creator:
- Guimarães Gois, Paula Suellen, Franco, Priscila Silva, Cota Teixeira, Samuel, Guirelli, Pâmela Mendonça, de Araújo, Thádia Evelyn, da Fonseca Batistão, Deivid William, de Oliveira, Fernanda Chaves, Santos Ferreira, Gabriela Lícia, de Oliveira Gomes, Angelica, Favoreto Jr., Silvio, Mineo, José Roberto, de Freitas Barbosa, Bellisa, and Vieira Ferro, Eloisa Amália
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- clonal strains, macrophage polarisation, toxoplasmosis, and TgChBrUD2 strain
- Language:
- English
- Description:
- Toxoplasma gondii Nicolle et Manceaux, 1909, the etiologic agent of toxoplasmosis, was considered a clonal population with three distinct genetic lineages (I, II and III); however, sequence analysis of different strains has revealed distinct atypical genotypes. Macrophages are essential for immunity against toxoplasmosis and differential cell regulation may affect the course of the disease. In this context, our study aims to investigate the infection by TgChBrUD2, a highly virulent atypical Brazilian strain of T. gondii, on the activation and polarisation of human macrophages. Human macrophage-like cells obtained from THP-1 cells were infected with TgChBrUD2, RH or ME49 strains of T. gondii to evaluate the impact of parasite infection on macrophage polarisation. Our results indicate that the TgChBrUD2 and ME49 strains of T. gondii induced a classic activation of human macrophages, which was confirmed by the high rate of spindle-shaped macrophages, low amount of urea and increase in the levels of nitrite, as well as the down-regulation of M2-markers. In contrast, RH strain promoted an alternative activation of macrophages. The polarisation of human macrophages towards an M1 subtype mediated by TgChBrUD2 and ME49 strains resulted in a low parasite burden, with high levels of IL-6 and MIF. Finally, the M2 subtype triggered by the RH strain culminated in a lower intracellular proliferation index. We concluded that the atypical (TgChBrUD2) and clonal (ME49) strains are able to elicit an M1 subtype, which results in parasitism control, partially explained by the high levels of IL-6 and MIF produced during the infection by these genotypes. In contrast, the clonal (RH) strain promoted a macrophage polarisation towards an M2 subtype, marked by a high parasite burden, with a weak modulation of pro-inflammatory cytokines. Thus, atypical strains can present different mechanisms of pathogenicity and transmissibility compared to clonal strains, as well as they can use distinct strategies to evade the host's immune response and ensure their survival.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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