Invasive species Lemna L. (Lemnaceae) in the flora of Bulgaria

Background and Purpose: During the investigations of flora of Bulgaria new species from genus Lemna have been found in Bulgaria. Materials and methods: They were conducted during the period 2010 - 2015 for which purpose we explored diverse pools in different parts of Bulgaria (hot and cold swamps, spillages of rivers and streams, hot mineral waters). The species were determined by Flora of North America. Results: In the flora of Bulgaria we found the following new (invasive) species L. minuta KUNTH., L. obscura (AUSTIN) Daubs, L. perpusilla TORR. and L. valdiviana PHILIPI. Their morphology, chorology and ecology was recorded and data about the accompanying species are also given. Conclusion: Finding these Lemna species in several distant locations in our country is a clear indication that the species is transferred on the territory of Bulgaria a long time ago. The species are most likely invading from neighboring fields in Southeast Europe - Greece, Romania, Turkey and others

Sex- and injury-dependent nociceptive C-fibre temporal relay

Chronic pain is a debilitating condition, affecting significantly more females than males. It poses a significant clinical burden due to the currently limited effective treatments, reflecting limited understating of the mechanism underlying chronic pain states. Chronic pain symptoms include increased sensitivity to noxious heat stimuli (heat hypersensitivity), which is known to involve changes in the function of the pain-sensing C-fibres. It can also cause pain triggered by innocuous stimuli (allodynia), which is thought to involve central plasticity driven by the ongoing C-fibre activity. Given that majority of the studies investigating chronic pain mechanisms have been conducted primarily in males, it is therefore important to study the function of the pain-sensing C-fibres in both sexes. C-fibres display a unique phenomenon termed activity-dependent slowing (ADS) whereby repetitive stimulation results in a progressive slowing of action potential conduction velocity, which manifests as a progressive increase in response latency in both humans and animals. It has been shown to also alter the temporal relay of pain signals to the spinal cord, where pain processing occurs. In addition, C-fibre ADS has been demonstrated to be altered in neuropathic pain states and following tissue inflammation in a sex-dependent manner. Given the accumulating evidence for sex difference in acute and chronic pain sensitivity along with the recent findings of sex differences in the temporal relay of C-fibre mediated pain signals to the spinal cord in inflammatory pain states, this thesis aimed to study C-fibre ADS in both sexes in normal physiology and under pathological conditions. In addition, it aimed to determine the impact of C-fibre ADS on spinal heat pain processing in both sexes. C-fibre ADS was investigated, using compound action potential recordings in dorsal roots ex vivo, in normal physiology and in the incision-induced model of postoperative pain in juvenile rats of both sexes, with findings of incision-induced enhancement of ADS, which was more pronounced in females. This is proposed to contribute to the less pronounced reduction in peak heat hypersensitivity observed following incision in females. Given that the voltage-gated sodium (NaV) channels are implicated in C-fibre ADS, the impact of NaV channels on ADS in normal physiology and in the pathology of postoperative pain was explored in both sexes. Pharmacological manipulation of the tetrodotoxin-sensitive NaV channels suggests sex- and incision-dependent changes in NaV functional expression in different C-fibre subtypes. It has been previously demonstrated that blood plasma levels of the glycolytic metabolite methylglyoxal (MG) differentiate between diabetic neuropathy patients with or without pain symptoms, with one proposed mechanism of the MG-induced pain involving post-translational modifications of the NaV channels, which are also implicated in C-fibre ADS. Chronic but not acute application of MG was found to alter C-fibre ADS in a sex-dependent manner in juvenile rats, with females showing enhancement of ADS and males showing a reduction in ADS. These ADS findings can potentially contribute to the observed MG-induced heat hypersensitivity in males only. ADS has been suggested to provide a ‘memory’ of previous levels of activity, which could in turn influence responses to subsequent high-frequency stimuli, such that ADS induced by prolonged low-level firing, similar to spontaneous C-fibre firing observed in pain states, could impact subsequent responses to high frequency inputs by altering their ADS profile. This thesis has shown that prolonged low-frequency C-fibre stimulation could alter ADS levels in juvenile rats and adult mice in a sex-dependent manner. Given the fact that sex differences in thermal pain sensitivity have been shown to be strain- and species-dependent, the findings in this thesis of a more pronounced ADS in juvenile female Sprague-Dawley (SD) rats and in adult male C57BL/6 mice suggest that these may contribute to the previously observed higher heat thresholds in female SD rats and in male C57BL/6 mice. Patch clamp recording from noxious heat sensitive superficial dorsal horn neurons in adult mouse spinal cord slices, in both sexes, was used to assess the impact of ADS and dynamic memory on noxious heat processing on an individual spinal neuron level. In line with the observed more pronounced C-fibre ADS in the male C57BL/6 mice, there was more ADS in monosynaptic C-fibre inputs to the heat sensitive spinal neurons, which, however, was associated with an overall less pronounced evoked activity in those neurons in males. This finding likely reflects the initial less pronounced evoked activity of the heat sensitive spinal neurons in males, independent of C-fibre ADS. Using the length-dependency of ADS, it was demonstrated that pronounced ADS in monosynaptic C-fibre inputs is associated with less pronounced reduction in the activity of the heat sensitive spinal neurons in both sexes, suggesting C-fibre ADS as a potential mechanism involved in maintaining the activity of the heat sensitive spinal neurons following repetitive simulation. Dynamic memory significantly altered monosynaptic C-fibre input to noxious heat sensitive superficial dorsal horn neurons in both sexes, increasing the number of C-fibre synaptic input failures, which was reflected in the pronounced reduction of the activity of the heat sensitive spinal neurons in both sexes, suggesting that dynamic memory may act as an intrinsic self-inhibitory mechanism to limit the activity of the heat sensitive spinal neurons. This thesis proposes a role for C-fibre ADS in modulating noxious heat sensitivity in a sex-dependent manner in normal physiology and in different pain pathologies. In addition, this work highlights the potential influence of ADS on spinal circuits involved in noxious heat processing

The Seminar as a Site of Critical Pedagogy: Progressing Equity, Diversity, and Inclusion Across EUt+

A concern for inclusivity has become a strategic planning of higher education institutions throughout Europe. The purpose of this A key mechanism through which this concern for inclusivity can be realised is through an approach to processes of curriculum design and teaching practice that are informed by the core commitments of critical pedagogy. The purpose of this paper is to reflect on the extent to which seminars organised around the themes of inclusivity successfully enacted a critical pedagogical approach in each of our respective contexts. Our paper reflects on our experiences organising and engaging in these seminars with the view to offering ‘lessons learned’ for future seminars within EUt+

Vers un procédé Fenton hétérogène pour le traitement en continu d’eau polluée par des polluants pharmaceutiques

Ce travail a pour objectif de développer un procédé couplant séparation membranaire et oxydation (photo-) Fenton hétérogène pour l’élimination du paracétamol dans l’eau. La réaction a d’abord été étudiée avec le fer en solution à pH acide (2,6) pour servir de référence aux études hétérogènes ultérieures. La méthodologie des plans d’expériences a permis de déterminer les paramètres influents (parmi température, concentrations d’oxydant et de catalyseur) et leurs interactions, et de modéliser les performances du procédé homogène. Des oxydes de fer sous la forme de particules nano- et micro-structurées (hématite, maghémite et magnétite) ou supportés sur zéolithes (type MFI ou BEA) ont ensuite été testés comme catalyseurs de l’oxydation Fenton. Pour chaque système étudié, on a évalué la conversion du polluant et du Carbone Organique Total (COT), mais aussi la stabilité du catalyseur : quantité de fer lixivié et activité du métal passé en solution (pour découpler la contribution du mécanisme homogène associé). L’effet des paramètres opératoires a ensuite été à nouveau évalué pour les catalyseurs sélectionnés (magnétite nanostructurée et Fe/MFI). Pour l’oxyde non supporté, l’étude met en évidence le rôle positif d’une augmentation de la température. A température et pH donnés, le rapport initial [oxyde de fer] / [H2O2] apparaît aussi comme le paramètre essentiel qui contrôle le taux de minéralisation, avec une inhibition de la réaction lorsque H2O2 est en trop large excès. Au contraire, pour le catalyseur Fe/MFI, une augmentation de la concentration d’oxydant se révèle bénéfique (sa consommation étant pratiquement totale dans tous les cas), et il y a peu d’effet de la température. Par ailleurs, la magnétite se révèle efficace à pH acide uniquement, tandis que le catalyseur supporté présente la même activité avec ou sans acidification préalable. L’irradiation UV améliore les performances de ces deux catalyseurs avec un abattement du COT en solution jusqu’à 70% en 5 heures, contre 98% pour le système homogène dans des conditions similaires. Les premiers tests en continu avec des particules de Fe/MFI retenues par une membrane d’ultrafiltration immergée sont prometteurs, puisque l’activité est restée stable pendant plus de 40 h. ABSTRACT : This work aims to develop a process coupling membrane separation and heterogeneous (photo-) Fenton oxidation for the elimination of paracetamol in water. The reaction was first studied with dissolved iron in acidic solution (pH 2.6), as a reference for the subsequent heterogeneous studies. The methodology of experimental design was used to determine the significant parameters (including temperature, oxidant and catalyst concentrations) and their interactions, and to model the performance of the homogeneous process. Iron oxides as nano- and micro-structured particles (hematite, maghemite and magnetite) or supported on zeolites (MFI or BEA type) were then tested as catalysts for the Fenton oxidation. For each studied system the conversions of pollutant and Total Organic Carbon (TOC) were evaluated, as well as the catalyst stability: amount and activity of leached iron (in order to decouple the contribution of homogeneous mechanism). The effect of process parameters was then again evaluated for the selected catalysts (nanostructured magnetite and Fe/MFI). For magnetite, the study reveals a positive effect of temperature. At given temperature and pH, the initial ratio of [iron oxide] to [H2O2] also appears as a key parameter that controls the mineralization yield, with an inhibition of the reaction when H2O2 is in large excess. Conversely, for Fe/MFI catalyst, the increase in oxidant concentration is beneficial (oxidant being almost fully consumed in all cases), and temperature has a poor effect. Furthermore, magnetite is only effective at acidic pH, while supported catalyst exhibits same activity with or without prior acidification. UV irradiation improves the performance of these catalysts with a reduction of TOC in solution up to 70% within 5 hours, against 98% for the homogeneous system under similar conditions. The results of the first continuous test, performed with Fe/MFI particles retained by a submerged ultrafiltration membrane, are promising: a stable activity has been observed for over 40 h

Ефект на Acorus calamus L. екстракт върху растежа и кръвните параметри на обикновен шаран (Cyprinus carpio L.), отглеждан в рециркулационна система

The aim of this study was to determine the effect of the sweet flag (A. calamus L.) extract addition of growth performance, haematological (white blood cells, red blood cells, hemoglobin, hematocrit) and biochemical (glucose, urea, creatinine, total protein, albumin, ASAT, ALAT, Ca, P, Mg, triglycerides, cholesterol) blood parameters of common carp (Cyprinus carpio L.) cultivated in recirculation system. Carps were randomly selected and distributed into four concrete tanks for the growth trial (8 fish/tank). Fish were divided into experimental (E) and control groups (C), each of them with two replicates and mean initial weight 908.5±171.2 g and 913.8±147.4 g, respectively. They were fed with pelleted carp feed with 25% crude protein, produced by the "Top mix" company, having a granule size of 6 mm. To the fish feed on the experimental group (E) was added 1% aqueous extract of A. calamus root, as well as oiling the pellets with 5 mL of sunflower oil for every 100 g of feed. Carps from control group (C) were fed with feed only greased with the same amount of sunflower oil. The daily ration that the studied fish received was 1.8% of their live weight. The duration of the trial period was 45 days. At the end of the experiment with 5.2% was measured a higher average live weight in the fish receiving the sweet flag supplement compare to the value of this parameter of carps from control group, and the differences were statistically significant (P0.05).Better blood biochemical and haematological parameters were measured in carp fed with sweet flag supplement.Целта на това проучване е да се определи ефектът от добавянето на екстракт от блатен аир (A. calamus L) върху растежа, хематологични (бели кръвни клетки, червени кръвни клетки, хемоглобин, хематокрит) и биохимични (глюкоза, урея, креатинин, общ протеин, албумин, ASAT, ALAT, Ca, P, Mg, триглицериди, холестерол) кръвни параметри на обикновен шаран (Cyprinus carpio L.), отглеждан в рециркулационна система. Рибите се разделят на експериментални (Е) и контролни групи (С), всяка от тях с две повторения и средно тегло 908.5 ± 171.2 g и 913.8 ± 147.4 g, съответно. Те са хранени с гранулиран фураж за шарани с 25% суров протеин, произведен от фирма "Top mix", с размер на гранулите 6 mm. Към храната за рибите от експерименталната група (Е) се прибавя 1% воден екстракт от корен на A. calamus, както и омасляване на пелетите с 5 мл слънчогледово масло на всеки 100 г фураж. Шараните от контролната група (С) са хранени с фураж, само омаслен със същото количество слънчогледово масло. Дневната дажба на изследваната риба е 1.8% от тяхното живо тегло. Продължителността на експерименталния период е 45 дни. В края на експеримента с 5.2% се измерва по-високо средно живо тегло на рибата, получаваща добавката с блатен аир, в сравнение със стойността на този параметър за шараните от контролната група, като разликите са статистически значими (Р0,05). По-високи биохимични и хематологични параметри на кръвта са измерени при шараните, хранени с добавка на блатен аир

Treatment of wastewater originating from aquaculture and biomass production in laboratory algae bioreactor using different carbon sources

The aim of present study was to explore the effect of different carbon sources on biomass accumulation in microalgae Nannochloropsis oculata and Tetraselmis chuii and their ability to remove N and P compounds during their cultivation in aquaculture wastewater. Microalgae cultivation was performed in laboratory bioreactor consisted from 500 mL Erlenmeyer flasks, containing 250 mL wastewater from semi closed recirculation aquaculture system. The cultures were maintained at room temperature (25-27ºC) on a fluorescent light with a light: dark photoperiod of 15 h: 9 h. The microalgae species were cultivated in wastewater with different carbon sources: glucose, lactose and saccharose. The growth of strains was checked for 96 h period. In the present study, N. oculata and T. chuii showed better growth in wastewater from aquaculture with saccharose carbon source during the experiment. The most effective reduce of nitrate and total nitrogen was proved in N. oculata cultivated in wastewater with glucose as carbon source. T. chuii cultivated in wastewater containing glucose showed 8.27% better cleaning effect in ammonium compared with N. oculata. T. chuii grew in wastewater with glucose as carbon source showed 19.5% better removal effect in phosphate compared with N. oculata strain

Treatment of wastewater originating from aquaculture and biomass production in laboratory algae bioreactor using different carbon sources

The aim of present study was to explore the effect of different carbon sources on biomass accumulation in microalgae Nannochloropsis oculata and Tetraselmis chuii and their ability to remove N and P compounds during their cultivation in aquaculture wastewater. Microalgae cultivation was performed in laboratory bioreactor consisted from 500 mL Erlenmeyer flasks, containing 250 mL wastewater from semi closed recirculation aquaculture system. The cultures were maintained at room temperature (25-27ºC) on a fluorescent light with a light: dark photoperiod of 15 h: 9 h. The microalgae species were cultivated in wastewater with different carbon sources: glucose, lactose and saccharose. The growth of strains was checked for 96 h period. In the present study, N. oculata and T. chuii showed better growth in wastewater from aquaculture with saccharose carbon source during the experiment. The most effective reduce of nitrate and total nitrogen was proved in N. oculata cultivated in wastewater with glucose as carbon source. T. chuii cultivated in wastewater containing glucose showed 8.27% better cleaning effect in ammonium compared with N. oculata. T. chuii grew in wastewater with glucose as carbon source showed 19.5% better removal effect in phosphate compared with N. oculata strain