Environmental factors affecting mayfly assemblages in tufa-depositing habitats of the Dinaric Karst

Remarkably, unlike other parts of Europe, the ecology of mayflies in the southeastern regions is still poorly known. Here we present the first comprehensive study of Ephemeroptera in the tufa-depositing habitats of the Dinaric Karst. The study was conducted in Plitvice Lakes National Park monthly during a one-year period (2007–2008) in different types of habitats (springs, streams, mountainous rivers, tufa barriers). The aims of the study were to determine mayfly composition, abundance, spatial distribution and habitat preferences, and to examine the environmental factors important for the structuring of mayfly assemblages in Plitvice Lakes National Park. The mayfly fauna of tufa-depositing habitats was composed of 14 species (20 taxa). Water temperature, pH and ammonium concentration were the most important environmental variables explaining mayfly assemblages. Mayfly assemblages grouped according to habitat type. Generally, the most favourable habitat type was mountainous stream, tufa barriers were less favourable, and the least favourable were springs. Our results confirmed that mayflies are a powerful tool as descriptors of their environment, as the presence or absence of certain mayflies was strongly influenced by physico-chemical water properties

The effect of the FKBP5 polymorphisms, childhood trauma and neuroticism on psychotic disorders.

Spektar psihotičnih poremećaja, od kojih je najteže oboljenje shizofrenija, čine složene nasledne poligenske bolesti kod kojih, pored genetičkih faktora, bitnu ulogu u etiologiji bolesti imaju psihosocijalni faktori rizika, kao što su trauma u detinjstvu i neuroticizam. Neurobiološki mehanizam kojim bi se objasnio uticaj psihosocijalnih faktora rizika na obolevanje od psihotičnog poremećaja još uvek nije poznat. Jedan od ponuđenih modela bolesti kojim bi se pokazala njihova veza jeste dijateza-stres model. Ovaj model ističe značaj interakcije biološke vulnerabilnost na stres (povišena stres-senzitivnost) i nepovoljnih životnih događaja u ranom životnom dobu (trauma u detinjstvu) na podložnost za nastanak psihotičnog poremećaja. Takođe, psihološki faktor rizika (neuroticizam) uključen je u ovaj model s obzirom da je neuroticizam marker stresvulnerabilnosti, odnosno fenotip kojim se opisuje povišena senzitivnost na stres. Interesantno je da je povišena senzitivnost na stres uočena ne samo kod pacijenata sa psihotičnim poremećajem, već i kod njihovih prvostepenih srodnika, što govori u prilog nasledne osnove stres-senzitivnosti. Najprihvaćeniji neurobiološki mehanizam dijateza-stres modela jeste poremećaj aktivnosti hipotalamo-hipofizno-adrenalne (HPA) osovine. Molekularna osnova disregulacije HPA osovine proučava se najviše u domenu poremećene glukokortikoidne signalizacije, gde glavnu ulogu ima glukokortikoidni receptor (GR). Ključni regulator GR jeste protein FK506-binding protein 51(FKBP51), ko-šaperon (co-chaperone) heatschock proteina 90 (hsp90), koji posreduje u translokaciji kortizol-GR kompleksa iz citoplazme u nukleus, a time i u GR-posredovanoj genskoj transkripciji. Gen koji kodira ovaj protein jeste FKBP5 gen. Ispitivanja polimorfizama u FKBP5 genu pokazala su da određeni rizični aleli imaju funkcionalni uticaj na ekspresiju FKBP51, kao i da u interakciji sa stresnim događajima predstavljaju značajne prediktore za različitu psihopatologiju indukovanu stresom, među kojima su i psihotični pormećaji...Psychotic disorders and schizophrenia, as the most severe psychotic disorder, are complex, heritable and polygenic diseases in which, beside genetics influence, psyschosocial risk factors, such as childhood trauma and neuroticism, play important roles. Neurobiological mechanisms which could explain relationship between psychosocial risk factors and psychotic disorders are still unknown. One of the proposed model is diathesisstres model of psychosis. This model suggests that interaction between biological vulnerability to stress (increased stress-sensitivity) and stressful life events is crucial for the development of psychotic disorders. Additionally, this model highlights the role of psychological risk factor (neuroticism) as the most promising marker for stressvulnerability, and thus phenotype for increased stress-sensitivity. Notably, increased stress-sensitivity is observed not only in patients with psychotic dirorders but also in their healthy siblings, suggesting that stress-sensitivity could be heritable marker. The most accepted neurobiological mechanism of diathesis-stress model is altered activity of the hypothalamic-pituitary-adrenal (HPA) axis. Molecular pathway for dysregulation of the HPA axis is studied mostly in the domain of impaired glucocorticoid signalization, where the glucocorticoid receptor (GR) has the main role. A key regulator of the GR activity is FK506-binding protein 51 (FKBP51), co-chaperone (co-chaperone) of heat-schock protein 90 (hsp90), which mediates the translocation of cortisol-GR complex from the cytoplasm to the nucleus, and thus in the GR-mediated gene transcription. The gene encoding this protein is FKBP5 gene. Studies of the FKBP5 polymorphisms have shown that certain risk alleles have functional significance on the expression of FKBP51, and interact with stressful life events to predict stress-induced psychopathology such as psychotic disorders. Given that the role of FKBP5 gene in diathesis-stress model of psychotic disorders is a new topic in psychotic research field, further investigation of the impact of the FKBP5 genetic variants and childhood trauma on the disease, as well as its potential effect on the phenotype of stress-sensitivity (neuroticism) are warranted..

Projekt terenskog pregleda područja grada Nove Gradiške

U proljeće 1997. godine Odsjek za arheologiju Filozofskog fakulteta Sveučilišta u Zagrebu proveo je u suradnji sa Zavičajnim muzejom Nova Gradiška projekt sustavnog terenskog pregleda područja grada Nova Gradiška. Projekt je obuhvaćao teritorij katastarskih općina Nova Gradiška, rešetari, Cernik, Baćin Dol i Šumetlica, a istraživanja su registrirala 24 nalazišta iz prapovijesnog i srednjovjekovnog perioda

Defining of the Kinetics of Microbial Oxidation Process Events with Reference to L-Sorbose Formation in a Large Range of Culture Conditions

This work refers to the study of the batch and fed batch cultures of an industrially applicable microbial strain termed Gluconobacter suboxydans S-22, capable of converting D-sorbitol into L-sorbose and D-glucose into D-gluconic acid at extremely high substrate mass concentrations. Media based on CSL-filtrate and containing different D-sorbitol concentrations were applied to performexperim ents. Studied were the effects of D-sorbitol and L-sorbose concentrations on the kinetics of microbial growth and D-sorbitol conversion into L-sorbose, and of microbial cell metabolism on the oxygen solubility and water activity, on the oxygen transfer and uptake rates and on the bioprocess final L-sorbose yield. In order to define the process relationships and describe the kinetics of all relevant process events in a large range of reaction conditions, a mathematical model based on corresponding differential equations was developed. The applicability of the mathematical model was tested by computer simulation. Data of computer simulations fitted well to experimental data. Changes of biomass, D-sorbitol, L-sorbose and dissolved oxygen concentrations during the batch and fed batch cultures can be well explained by applied mathematical model regardless of whether they refer to the reaction system of commonly dissolved substance mass concentration (close to 200 g L–1) or to the reaction systemof extremely highly dissolved and total substance concentrations (above 700 g L–1). Excellent correlation coefficients (0.99693 – 0.99995) expressing the agreement of the theoretical with experimental data were found for compared biomass, D-sorbitol, L-sorbose and dissolved oxygen concentrations. Results confirmed the hypothesis that the water activity can be expressed as a function of oxygen solubility in the investigated reaction system

Influence of Different Yeast Strains on Metabolism of Tryptophan and Indole-3-Acetic Acid During Fermentation

The effect of supplementation of Riesling (Vitis vinifera L.) must with ammonium sulphate (AS) ontryptophan (Trp) and indole-3-acetic acid (IAA) metabolism during alcoholic fermentation with fourcommercial yeast strains (Uvaferm CEG, Lalvin Cross Evolution, Anchor VIN 13 and Anchor exoticSPH) were examined. AS addition reduced Trp uptake by yeasts from 1% to 15%. Wines produced byAnchor VIN 13 and Uvaferm CEG yeasts with AS addition had the highest concentrations of Trp (0.60and 0.59 mg/L respectively). Concentrations of total and bound IAA decreased during all treatments. Atthe end of fermentation the highest concentration of free IAA was measured in the control must inoculatedwith Anchor VIN 13 yeast (35.83 μg/L) and the lowest in the sample inoculated with Uvaferm CEG yeast(13.08 μg/L). Anchor VIN 13 yeast showed the strongest change in metabolism due to AS addition duringfermentation. 2-Aminoacetophenone (2-AAP) formation was not observed in all the studied wines

Microhabitat selection and distribution of functional feeding groups of mayfly larvae (Ephemeroptera) in lotic karst habitats

Research examining mayfly ecology in karst streams and rivers has increased in recent years, though microhabitat preferences remain poorly characterized. We examined mayfly assemblage taxonomy, functional feeding groups and microhabitat preferences in two contrasting lotic Dinaric karst catchments, one pristine and one anthropogenically impacted. At monthly intervals over a one-year period, all major microhabitats (i.e. dominated by boulders, cobbles, sand, silt, mosses, or angiosperms) were sampled at sites spanning springs, upper, middle and lower river reaches, and tufa barriers. In both catchments, mayfly species richness was comparable among microhabitats, while mayfly abundance was highest on mosses and lowest on silt. NMDS ordination did not group assemblages according to microhabitat type, which may reflect the greater influence of physical and chemical water properties. In both catchments and all microhabitats, mayfly assemblages were dominated by grazers/scrapers at upstream sites and by detritivores at downstream sites. Active filter feeders were more abundant in microhabitats with silt substrates and lower current velocities. This study demonstrated that certain mayfly species strongly preferred a specific microhabitat type, reflecting their water current preferences and feeding strategies, while other species shifted between microhabitats, likely in search of food resources and shelter. The results emphasize the importance of habitat heterogeneity in supporting diverse communities in karst rivers