120 research outputs found
ToksiÄni uÄinci patulina na timus muĹžjaka ĹĄtakora u razvoju
Patulin is a mycotoxin produced by several Penicillium, Aspergillus, and Byssachlamys species growing on food products. In this study, we investigated the effects of patulin on the thymus of growing male rats aged fi ve to six weeks. The rats were receiving it orally at a dose of 0.1 mg kg-1 bw a day for either 60 or 90 days. At the end of the experiment, the thymus was examined for histopathology by light microscopy and for epidermal growth factor (EGF) and its receptor (EGFR) by immunolocalisation. For morphometry we used the Bs200prop program to analyse images obtained with the Olympus BX51 light microscope. Cell ultrastructure was studied by electron microscopy. In rats treated with patulin, the thymus showed
haemorrhage, plasma cell hyperplasia, a dilation and fi brosis in the cortex, enlarged interstitial tissue between the thymic lobules, enlarged fat tissue, thinning of the cortex, and blurring of the cortico-medullary demarcation. Electron microscopy showed signs of cell destruction, abnormalities of the nucleus and organelles, and loss of mitochondrial cristae. However, no differences were observed in thymus EGF and EGFR immunoreactivity between treated and control rats.Patulin je mikotoksin koji proizvode plijesni sojeva Penicillium, Aspergillus i Byssachlamys na razliÄitim prehrambenim proizvodima kao podlozi. UÄinke patulina istraĹžili smo na timusu muĹžjaka ĹĄtakora u
razvoju (dobi 5 do 6 tjedana). Mikotoksin je Ĺživotinjama davan per os u dnevnoj dozi 0,1 mg kg-1 tj. t. 60 odnosno 90 dana. Na kraju pokusa ĹĄtakori su Ĺžrtvovani, timus je podvrgnut histoloĹĄkim analizama s pomoÄu svjetlosne mikroskopije, a imunocitokemijskim je metodama istraĹžena staniÄna lokalizacija epidermalnog faktora rasta (EGF) i njegova receptora (EGFR). Morfometrijska analiza provedena je s pomoÄu raÄunalnog programa Bs200prop povezanog u sustav sa svjetlosnim mikroskopom Olympus BX51. Elektronskomikroskopski je istraĹžena ultrastruktura stanica timusa. UtvrÄeno je da patulin izaziva krvaranja u timusu, hiperplaziju plazma-stanica, dilataciju i fi brozu u kortikalnoj regiji timusa, ĹĄirenje
intersticijskog tkiva izmeÄu reĹžnjeva timusa, poveÄanje masnih stanica, smanjenje debljine kore timusa te nestanak kortiko-medularne demarkacije. Elektronskomikroskopski u tkivu timusa ĹĄtakora tretiranih patulinom uoÄeni su znakovi raspadanja stanica, abnormalnosti jezgre i organela te gubitak mitohondrijskih krista. UnatoÄ navedenomu, na presjecima tkiva kontrolnih ĹĄtakora i ĹĄtakora tretiranih patulinom nismo utvrdili razlike u imunoreaktivnosti EGF i EGFR, ĹĄto bi trebalo dodatno istraĹžiti osjetljivijim molekularnim
metodama
Early anthropogenic transformation of the Danube-Black Sea system
Š The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Reports 2 (2012): 582, doi:10.1038/srep00582.Over the last century humans have altered the export of fluvial materials leading to significant changes in morphology, chemistry, and biology of the coastal ocean. Here we present sedimentary, paleoenvironmental and paleogenetic evidence to show that the Black Sea, a nearly enclosed marine basin, was affected by land use long before the changes of the Industrial Era. Although watershed hydroclimate was spatially and temporally variable over the last ~3000 years, surface salinity dropped systematically in the Black Sea. Sediment loads delivered by Danube River, the main tributary of the Black Sea, significantly increased as land use intensified in the last two millennia, which led to a rapid expansion of its delta. Lastly, proliferation of diatoms and dinoflagellates over the last five to six centuries, when intensive deforestation occurred in Eastern Europe, points to an anthropogenic pulse of river-borne nutrients that radically transformed the food web structure in the Black Sea.This study was supported by grants OISE 0637108, EAR
0952146, OCE 0602423 and OCE 0825020 from the National Science Foundation and
grants from the Woods Hole Oceanographic Institution
Recommended from our members
(In)Complete acquisition of Turkish among Turkish German bilinguals in Germany and Turkey: an analysis of complex embeddings in narratives
Although most researchers recognise that the language repertoire of bilinguals can mvary, few studies have tried to address variation in bilingual competence in any
detail. This study aims to take a first step towards further understanding the way in which bilingual competencies can vary at the level of syntax by comparing the use of syntactic embeddings among three different groups of Turkish/German bilinguals.
The approach of the present paper is new in that different groups of bilinguals are compared with each other, and not only with monolingual speakers, as is common in most studies in the field. The analysis focuses on differences in the use of embeddings in Turkish, which are generally considered to be one of the more complex aspects of Turkish grammar. The study shows that young Turkish/German
bilingual adults who were born and raised in Germany use fewer, and less complex embeddings than Turkish/German bilingual returnees who had lived in Turkey for
eight years at the time of recording. The present study provides new insights in the nature of bilingual competence, as well as a new perspective on syntactic change in immigrant Turkish as spoken in Europe
Mechanisms for primordial black hole production in string theory
We consider mechanisms for producing a significant population of primordial black holes (PBHs) within string inspired single field models of inflation. The production of PBHs requires a large amplification in the power spectrum of curvature perturbations between scales associated with CMB and PBH formation. In principle, this can be achieved by temporarily breaking the slow-roll conditions during inflation. In this work, we identify two string setups that can realise this process. In string axion models of inflation, subleading non-perturbative effects can superimpose steep cliffs and gentle plateaus onto the leading axion potential. The cliffs can momentarily violate the slow-roll conditions, and the plateaus can lead to phases of ultra slow-roll inflation. We thus achieve a string motivated model which both matches the Planck observations at CMB scales and produces a population of light PBHs, which can account for an order one fraction of dark matter. In DBI models of inflation, a sharp increase in the speed of sound sourced by a steep downward step in the warp factor can drive the amplification. In this scenario, discovery of PBHs could indicate non-trivial dynamics in the bulk, such as flux-antibrane annihilation at the tip of a warped throat
Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age.
The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research. [Abstract copyright: Copyright Š 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.
Cosmology with the Laser Interferometer Space Antenna
The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational wave observations by LISA to probe the universe
The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats
The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yetâundescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well
Structure of Dark Triad Dirty Dozen Across Eight World Regions
The Dark Triad (i.e., narcissism, psychopathy, Machiavellianism) has garnered intense attention over the past 15 years. We examined the structure of these traitsâ measureâthe Dark Triad Dirty Dozen (DTDD)âin a sample of 11,488 participants from three W.E.I.R.D. (i.e., North America, Oceania, Western Europe) and five non-W.E.I.R.D. (i.e., Asia, Middle East, non-Western Europe, South America, sub-Saharan Africa) world regions. The results confirmed the measurement invariance of the DTDD across participantsâ sex in all world regions, with men scoring higher than women on all traits (except for psychopathy in Asia, where the difference was not significant). We found evidence for metric (and partial scalar) measurement invariance within and between W.E.I.R.D. and non-W.E.I.R.D. world regions. The results generally support the structure of the DTDD
- âŚ