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462. Parasite richness in fish larvae from the nearshore waters of central and northern Chile

Creator:
Muñoz, Gabriela, Landaeta, Mauricio F, Palacios-Fuentes, Pamela, López, Zambra, and González, María Teresa
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
ryby, parazitologie, fishes, parasitology, copepods, Pennellidae, Caligidae, fish larva assemblage, intertidal fish, 2, and 59
Language:
English
Description:
In the present study, we determine the presence of parasites in fish larvae collected from nearshore waters along the northern and central coast of Chile. The parasites were identified to the lowest possible taxonomic level based on morphological and molecular analyses. The fish sample was composed of 5 574 fish larvae. Of these, 3% harboured only larval ectoparasitic copepods whereas no endoparasites were found in the 1 141 fish evaluated for this group of parasites. The parasitic copepods collected were initially classified as 'morphotypes' according to differences in morphological characteristics. They were then analysed using molecular techniques based on the 28S and COI genes. Seven morphotypes of parasitic copepods (mostly at chalimus stages) were recognised: two of the morphotypes belonged to Pennellidae Burmeister, 1835, three to Caligidae Burmeister, 1835 and two were not identified. Only five morphotypes of copepods were analysed using molecular sequences, which confirmed the existence of six species: two pennellids of the genus Trifur Wilson, 1917 and two caligids of the genus Caligus Müller, 1785, plus two additional species that were morphologically different from these taxa. The pennellids were present in several fish species, being generally more prevalent than the caligids, in both the central and northern localities of Chile. Multispecies infections in larval fish were infrequent (< 1%). We conclude that fish larvae were rich in parasites, considering that these hosts exhibited small body sizes and were very young. We suggest that fish larvae could play a role, as intermediate hosts, in the life cycle of the parasitic copepods found., Gabriela Muñoz, Mauricio F. Landaeta, Pamela Palacios-Fuentes, Zambra López, María Teresa González., and Obsahuje bibliografii
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463. Parasites of cartilaginous fishes (Chondrichthyes) in South Africa: a neglected field of marine science

Creator:
Schaeffner, Bjoern C and Smit, Nico J
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
příčnoústí, parazitické organismy, parazit a hostitel, Elasmobranchii, parasitic organisms, parasite and host, Holocephali, diversity, host-parasite list, parasite-host list, 2, and 59
Language:
English
Description:
Southern Africa is considered one of the world's 'hotspots' for the diversity of cartilaginous fishes (Chondrichthyes), with currently 204 reported species. Although numerous literature records and treatises on chondrichthyan fishes are available, a paucity of information exists on the biodiversity of their parasites. Chondrichthyan fishes are parasitised by several groups of protozoan and metazoan organisms that live either permanently or temporarily on and within their hosts. Reports of parasites infecting elasmobranchs and holocephalans in South Africa are sparse and information on most parasitic groups is fragmentary or entirely lacking. Parasitic copepods constitute the best-studied group with currently 70 described species (excluding undescribed species or nomina nuda) from chondrichthyans. Given the large number of chondrichthyan species present in southern Africa, it is expected that only a mere fraction of the parasite diversity has been discovered to date and numerous species await discovery and description. This review summarises information on all groups of parasites of chondrichthyan hosts and demonstrates the current knowledge of chondrichthyan parasites in South Africa. Checklists are provided displaying the host-parasite and parasite-host data known to date., Bjoern C. Schaeffner, Nico J. Smit., and Obsahuje bibliografii
Rights:
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464. Parental care and offspring survival in Pterostichus anthracinus (Coleoptera: Carabidae): an experimental study

Creator:
Kolesnikov, Felix N. and Karamyan, Arevik N.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
Coleoptera, Carabidae, ground beetles, Pterostichus anthracinus, parental care, presocial behaviour, subsocial behaviour, predation pressure, fungal attack, parental removal, and offspring survival
Language:
English
Description:
Parental care in which females attend their offspring is recorded in over 30 species of ground beetles. Despite this, there is no quantitative data on the fate of the offspring when the mother is experimentally removed. This paper investigates parental care in Pterostichus anthracinus (Coleoptera: Carabidae). The objectives of the study were to estimate: (1) egg survival when the female is removed; (2) the ability of females to defend their eggs from attack by predators; (3) the ability of females to repair a damaged nest in which egg attendance takes place. In the laboratory, the reproductive activity of P. anthracinus lasted four months (from May till August) and peaked in late June. Mean (± SE) number of eggs in each clutch was 25.25 ± 2.19. All of the egg clutches were guarded by a female. Female attendance had no effect on egg mortality due to microbial attack. The duration of embryonic development lasted on average 5.2–5.3 days, and did not differ between the groups with and without maternal care. In P. anthracinus maternal care is important in preventing egg mortality due to predators. In the laboratory the percentage mortality of eggs without maternal care due to predators was 100%. In the group in which females attended their eggs, percentage mortality of offspring due to predation was about 51%. Female ability to repair damaged nests is important in preventing dehydration and reducing predation pressure. This laboratory study provides the fi rst quantitative data on the importance of maternal care in ground beetles in determining the survival of their offspring.
Rights:
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465. Partitioning evapotranspiration using stable isotopes and Lagrangian dispersion analysis in a small agricultural catchment

Creator:
Hogan, Patrick , Parajka, Juraj , Heng, Lee , Strauss, Peter , and Blöschl, Günter
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
evapotranspiration partitioning, stable isotopes, and Lagrangian dispersion theory
Language:
Slovak
Description:
Measuring evaporation and transpiration at the field scale is complicated due to the heterogeneity of the environment, with point measurements requiring upscaling and field measurements such as eddy covariance measuring only the evapotranspiration. During the summer of 2014 an eddy covariance device was used to measure the evapotranspiration of a growing maize field at the HOAL catchment. The stable isotope technique and a Lagrangian near field theory (LNF) were then utilized to partition the evapotranspiration into evaporation and transpiration, using the concentration and isotopic ratio of water vapour within the canopy. The stable isotope estimates of the daily averages of the fraction of evapotranspiration (Ft) ranged from 43.0–88.5%, with an average value of 67.5%, while with the LNF method, Ft was found to range from 52.3–91.5% with an average value of 73.5%. Two different parameterizations for the turbulent statistics were used, with both giving similar R2 values, 0.65 and 0.63 for the Raupach and Leuning parameterizations, with the Raupach version performing slightly better. The stable isotope method demonstrated itself to be a more robust method, returning larger amounts of useable data, however this is limited by the requirement of much more additional data.
Rights:
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466. Partnerské strachy v období mladé dospělosti

Creator:
Kohoutová, Anežka, Daňsová, Petra, and Lacinová, Lenka
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
partnerské strachy, mladí dospělí, strachy z rozchodu, citová vazba, partnership fears, young adulthood, fear of breaking up, and attachment
Language:
Czech
Description:
Cíl. Cílem studie bylo popsat partnerské strachy typické pro období mladé dospělosti a zjistit, zda existují faktory, které predikují výskyt a intenzitu partnerských strachů v tomto období. Vzorek. Vzorek tvořilo 407 respondentů z longitudinálního projektu „Cesty do dospělosti“ (81 % žen, průměrný věk = 23,53 let; SD = 1,48; Min = 18,7, Max = 33). Metoda. Data byla získávána pomocí online dotazníků. Výpovědi o partnerských straších byly získávány metodou volných výpovědí. Dále byly administrovány tyto dotazníky- ECR-RS, QMI, Ex-bond. Výsledky. Volné výpovědi o subjektivně prožívaných straších byly kategorizovány do sedmi kategorií za pomoci tematické analýzy (Strachy z rozchodu, ze samoty, z nenalezení partnera, z partnerských neshod, s pochybnostmi o sobě v partnerství, z nevěry a generalizované partnerské strachy). Z výsledků regresní analýzy vyplývá, že existuje vztah mezi výskytem partnerských strachů, prožitkem rozchodu a vazbovou úzkostností k partnerovi. Dále byl detekován vztah mezi intenzitou partnerských strachů a pohlavím, existencí partnerského vztahu a opět vazbovou úzkostností k partnerovi. Limity. Limitem studie bylo především složení výzkumného souboru, kde byl významný nepoměr mužů a žen, vysokoškoláků a pracujících a také větší podíl respondentů starší věkové skupiny. and Objectives. The study aims at describe partnership fears in the young adulthood period and to examine the relationship between some factors (age, gender, attachment, break up, relationship with a partner) and presence and intensity of partnership fears. Sample. Overall, this study was participated in by 407 respondents from the longitudinal project “Cesty do dospělosti” (81% of women, the average age of the respondents was 23.53 years SD = 1,48; Min = 18,7, Max = 33). Method. Questionnaires were collected on-line (QMI, ECRRS, Ex-Bond). Partnerships fears were collected by open-ended questions on fears. Results. The open-ended answers were categorized by using thematic analysis, into 7 categories (Fear of breaking up, of remaining alone, of not finding a partner, of partners disagreements, fears associated with a sense of the incompetence in partnership, of infidelity and generalized partnership fears). Multiple regression analysis indicated that the anxious attachment dimension to the partner and the experience of break up were found to be significant predictors of the presence of partnership fears. The gender, the existence of partnership and attachment anxiety to the partner were found to be significant predictors of the intensity of partnership fears. Limits. The study impact is limited by the sample structure. The sample was over-represented by women, students and respondents of older age group.
Rights:
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467. Passive sinking into the snow as possible survival strategy during the off-host stage in an insect ectoparasite

Creator:
Kaunisto, Sirpa, Ylönen, Hannu, and Kortet, Raine
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
klošovití, jelenovití, nízké teploty, morfologie (biologie), kukly (zoologie), Hippoboscidae, Cervidae, low temperatures, morphology (biology), pupas, ectoparasite, invasive species, predation, 2, and 59
Language:
English
Description:
Abiotic and biotic factors determine success or failure of individual organisms, populations and species. The early life stages are often the most vulnerable to heavy mortality due to environmental conditions. The deer ked (Lipoptena cervi Linnaeus, 1758) is an invasive insect ectoparasite of cervids that spends an important period of the life cycle outside host as immobile pupa. During winter, dark-coloured pupae drop off the host onto the snow, where they are exposed to environmental temperature variation and predation as long as the new snowfall provides shelter against these mortality factors. The other possible option is to passively sink into the snow, which is aided by morphology of pupae. Here, we experimentally studied passive snow sinking capacity of pupae of L. cervi. We show that pupae have a notable passive snow sinking capacity, which is the most likely explained by pupal morphology enabling solar energy absorption and pupal weight. The present results can be used when planning future studies and when evaluating possible predation risk and overall survival of this invasive ectoparasite species in changing environmental conditions., Sirpa Kaunisto, Hannu Ylönen, Raine Kortet., and Obsahuje bibliografii
Rights:
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468. Pathological changes in the central nervous system following exposure to ionizing radiation

Creator:
Bálentová, Soňa and Adamkov, Marian
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
irradiation, radiation-induced brain injury, histopathological changes, cognitive impairment, and interventional therapy
Language:
English
Description:
Experimental studies in animals provide relevant knowledge about pathogenesis of radiation-induced injury to the central nervous system. Radiation-induced injury can alter neuronal, glial cell population, brain vasculature and may lead to molecular, cellular and functional consequences. Regarding to its fundamental role in the formation of new memories, spatial navigation and adult neurogenesis, the majority of studies have focused on the hippocampus. Most recent findings in cranial radiotherapy revealed that hippocampal avoidance prevents radiation-induced cognitive impairment of patients with brain primary tumors and metastases. However, numerous preclinical studies have shown that this problem is more complex. Regarding the fact, that the radiation-induced cognitive impairment reflects hippocampal and non-hippocampal compartments, it is highly important to investigate molecular, cellular and functional changes in different brain regions and their integration at clinically relevant doses and schedules. Here, we provide a literature review in order support the translation of preclinical findings to clinical practice and improve the physical and mental status of patients with brain tumors.
Rights:
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469. Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences

Creator:
Stožer, Andraž, Vodopivc, Peter, and Križančić Bombek, Lidija
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
tělesná cvičení, výstřední osobnosti, svaly, patopsychologie, exercises, eccentrics, muscles, pathopsychology, damage, 14, and 612
Language:
English
Description:
Extreme or unaccustomed eccentric exercise can cause exerciseinduced muscle damage, characterized by structural changes involving sarcomere, cytoskeletal, and membrane damage, with an increased permeability of sarcolemma for proteins. From a functional point of view, disrupted force transmission, altered calcium homeostasis, disruption of excitation-contraction coupling, as well as metabolic changes bring about loss of strength. Importantly, the trauma also invokes an inflammatory response and clinically presents itself by swelling, decreased range of motion, increased passive tension, soreness, and a transient decrease in insulin sensitivity. While being damaging and influencing heavily the ability to perform repeated bouts of exercise, changes produced by exercise-induced muscle damage seem to play a crucial role in myofibrillar adaptation. Additionally, eccentric exercise yields greater hypertrophy than isometric or concentric contractions and requires less in terms of metabolic energy and cardiovascular stress, making it especially suitable for the elderly and people with chronic diseases. This review focuses on our current knowledge of the mechanisms underlying exerciseinduced muscle damage, their dependence on genetic background, as well as their consequences at the structural, functional, metabolic, and clinical level. A comprehensive understanding of these is a prerequisite for proper inclusion of eccentric training in health promotion, rehabilitation, and performance enhancement., Andraž Stožer, Peter Vodopivc, Lidija Križančić Bombek., and Obsahuje bibliografii
Rights:
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470. Patterns in the distribution and directional asymmetry of fleas living on the northern white-breasted hedgehog Erinaceus roumanicus

Creator:
Dudek, Krzysztof, Földvári, Gábor, Majláthová, Viktória, Majláth, Igor, Rigó, Krisztina, Molnár, Viktor, Tóth, Mária, Jankowiak, Łukasz, and Piotr Tryjanowski
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
parazitologie, parasitology, morphometrics, Archaeopsylla erinacei, parasite morphology, co-infection, 2, and 59
Language:
English
Description:
Fleas infecting northern white-breasted hedgehogs, Erinaceus roumanicus (Barrett-Hamilton), collected from 2009-2011 in Budapest (Hungary) were studied. A total of 305 white-breasted hedgehogs were captured and 1,251 fleas were collected. The flea community comprised two species, the hedgehog flea Archaeopsylla erinacei (Bouche, 1835) and the dog flea Ctenocephalides canis (Curtis, 1826), although the latter was only found on three hedgehogs. Fleas were found on half of the host specimens (51%; n = 156) where their distribution was strongly aggregated. The sex ratio of A. erinacei was biased towards females and was correlated with host size. Interestingly, the sex ratio of fleas became more equal on heavier hosts. It had been expected that, under high competition, the sex ratio would be female biased because it is known that female ectoparasites dominate on poorer hosts. The body size of a random sample of 200 fleas (100 female and 100 male) was measured under a microscope. The analyses showed directional asymmetry in two features - the distance between the top of the head and the eye, and head length. In this two body traits the left side was significantly greater than right side in both sexes of A. erinacei. Our data shed light on the complex nature of the flea population infecting northern white-breasted hedgehogs in an urban area., Krzysztof Dudek, Gábor Földvári, Viktória Majláthová, Igor Majláth, Krisztina Rigó, Viktor Molnár, Mária Tóth, Łukasz Jankowiak, Piotr Tryjanowski., and Obsahuje bibliografii
Rights:
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