684 research outputs found

    Biosorption of Selected Heavy Metals by Green Algae, Spirogyra Species and Its Potential as a Pollution Biomonitor

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    In this paper, adsorption features of freshwater green algae as a function of contact time, initial pH and initial metal ion concentrations were studied using model solutions of metal ions with subsequent determination by flame atomic absorption spectrometry (FAAS). Green algae samples were employed as bioindicators of selected heavy metals in environmental water samples with determination using FAAS and ICP-OES (inductively-coupled plasma-optical emission spectrometry). The optimum pH for cadmium (Cd), chromium (Cr), copper (Cu) and lead (Pb) biosorption were found to be 5.5, 5.8, 5.9 and 5.0, respectively. The biosorption process follows second order kinetics and is well described by the Langmuir isotherm model. Adsorption capacities were found to be 22.52, 38.19, 35.59 and 94.34 mg/g for Cd, Cr, Cu and Pb, respectively, at contact times of 15-50 minutes and initial metal ion concentrations of 500-700 mg/L. Biomonitoring studies revealed great potential for freshwater green algae as a bioindicator with mean concentration factors in the range of 367-7154 for the selected elements, the uptake being mainly via a metabolically mediated pathway. This work has demonstrated the potential of freshwater green algae as both a biosorbent and a bioindicator for heavy metal pollution in water systems. Keywords: Green algae, Biosorption, Biomonitoring, Toxic metals, FTIR, ICP-OES

    Hubungan Infestasi Cacing Yang Ditularkan Melalui Tanah Dan Eosinofilia Pada Siswa SD Gmim Buha Manado

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    : Infestation of soil transmitted helminth is often found among communities in developing countries. This helminthic infestation can affect nutritional state, physical growth, mental, cognition, and intellectual deterioration in children. Increased eosinophils (eosinophilia) is often associated with diseases caused by worms and allergy. This study aimed to determine the links between investastion of soil transmitted helminth and esinophilia among students in SD GMIM Buha Manado. This was a prospective observational study with a cross-sectional approach. According to exclusive and inclusive criteria, 80 samples were obtained. Data were analyzed by using the Fisher Exact and Phy correlation coefficient analysis. The resluts showed that 17.5 % students were infected by Ascaris lumbricoides, meanwhile Trichuris trichiura and hookworm were not evident. The corelation test showed that there was a significant relationship between infestation of soil transmitted helminth and eosinophilia with a P-value = 0.001. Conclusion: There was a high significant relationship between infestation of soil transmitted helminth and eosinophilia among students of SD GMIM Buha Manado. The most frequent found was Ascaris lumbricoides and its infestation was marked by eosinophilia

    Meritocratic aspects concerning civil servant career: comparative study in Central and Eastern European countries

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    Central and Eastern Europe has known in the last 20 years profound changes. The shift from a dictatorial system to a democratic system forced the states from this area to adopt structural measures for all public institutions. In this context, the institution of "civil servant" could not remain unaffected. In the period of communist regimes, the institution of "civil servant" did not exist, the civil servant being just a simple employee of the state. Work relations were the same as for any employee. The shift to another political system, the democratic one, determined the reconsideration the role and the place of public administration, and implicit of civil servant in the framework of the state system. In this context, it has been a shift from the statute of simple employee to that of civil servant, representing the power of the state. In the process of accession to the European Union, the states from Central and Eastern Europe have been permanently pressured to clearly define a strategy concerning the competitiveness of public administration, concerning the statute and the career of civil servant. In the context of democratisation, we can notice that the principle of meritocracy has become a key principle in the civil servant's career. The term "meritocracy" is often used in order to describe a type of society in which wealth and social position are obtained mainly through competition or through ability or proved competences. A position invested with responsibilities and social prestige has to be acquired and not inherited or obtained by arbitrary criteria. Meritocracy represents also the term used to describe or to criticise a society in competition that accepts inequitable disparities of income, wealth and social position. Taking into account the above considerations, the present paper aims to achieve an analysis of meritocratic aspects in the systems of planning and promotion of civil servant's career in Central and Eastern Europe

    Responses to Drought and Salinity in the Endangered Species Ligularia sibirica (L.) Cass

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    [EN] The negative effects of environmental stress factors on plant distribution and survival are increasing due to climate change and anthropogenic activities. We have analysed some responses to abiotic stress in Ligularia sibirica, a postglacial relict that is critically endangered in Europe. L. sibirica seedlings were subjected to water or salt stress treatments in the greenhouse. After the treatments, plant material was harvested and several growth parameters were measured; leaf contents of common osmolytes, the degree of oxidative stress affecting the plants and the level of antioxidant phenolic compounds were also determined. Both, drought and, especially, salt stress had a negative effect on the growth of L. sibirica plants. Treated plants showed an increase in proline (Pro) and total soluble sugars (TSS) levels, stronger under salt stress. Malondialdehyde (MDA, an oxidative stress biomarker) contents almost doubled, and antioxidant phenolics increased significantly in salt-stressed, but not in water-stressed plants. Pro accumulation can be used as a salt and drought stress biomarker in L. sibirica and, together with TSS, likely contributes to osmotic adjustment under stress. Increase of antioxidant phenolics appears to partly compensate the salt-induced generation of oxidative stressMatei, AN.; Al Hassan, M.; Boscaiu Neagu, MT.; Alexiu, V.; Vicente Meana, Ó. (2016). Responses to Drought and Salinity in the Endangered Species Ligularia sibirica (L.) Cass. BULLETIN OF UNIVERSITY OF AGRICULTURAL SCIENCES AND VETERINARY MEDICINE. 73(2):252-253. doi:10.15835/buasvmcn-hort:12286S25225373

    RESEARCH REGARDING LABORATORY TESTING OF SOIL PROCESSING EQUIPMENT USING THE EFFECT OF ELECTRO-OSMOSIS

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    Electro-osmosis principle consists of the application of a direct current voltage for an anode-cathode system introduced into soil. The soil water transported from the anode to cathode, on the tool-soil contact surface will produce a lubrification of an active surface and through this a great decreasing of the friction forces and implicit of the energy needed for displacing the tool through the soil. The active surface of the tilling tool is chosen in order to minimize the frictions, respective the mechanic energies needed for tilling. This paper aims to increase the popularization of the electro-osmosis technique, highlighting the advantages of using such a method for soil improvements, as well as in view of optimizing the functional parameters of the soil tillage equipment

    Neural-immune-effector (NIE) cross-talk in vascular trophobiology: proposal for new and not yet exploited purinergic regulatory mechanisms

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    In a state-of-the-art approach, Dr. Hasséssian presents purinoceptor-mediated vasoconstriction/vasodilation mechanisms of the pulmonary circulation. He focuses on P2 purinoceptors of smooth muscle cells, endothelial cells, platelets and mast cells, without addressing P1 (adenosine) purinoceptors. Recently, the Burnstock's purinoceptorology is "arborizing" into a variety of members of P1 and P2 purinoceptor families classified by the International Union of Pharmacology. Here we would like to add some possible, new and not yet exploited, purinergic regulatory mechanisms to the Hasséssian's work. Accordingly, we shall briefly focus on the involvement of connective tissue (adventitial) mast cells and their interactions with perivascular nerves and medial smooth muscle cells.Biomedical Reviews 1994; 3: 81-86

    GENERAL CONSIDERATIONS CONCERNING THE EFFECTS OF ELECTRO-OSMOSIS ON DECREASING THE FORCES AND THE ENERGY NEEDED FOR TILLING THE SOIL

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    Electro-osmosis principle consists in the application of a direct current voltage for an anode-cathode system introduced into soil. The effect of this system consists of the mobilization of water particles from the soil and their transport, in a very short time, from the anode to cathode. The soil water transported from the anode to cathode, on the tool-soil contact surface, in consequence, will produce a lubrication of the active surface and thereby a considerable reduction of the friction forces and implicitly of the energy necessary to move the tool through the soil

    NF-κB-HOTAIR axis links DNA damage response, chemoresistance and cellular senescence in ovarian cancer.

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    The transcription factor nuclear factor kappa B (NF-κB) and the long non-coding RNA (lncRNA) HOTAIR (HOX transcript antisense RNA) play diverse functional roles in cancer. In this study, we show that upregulation of HOTAIR induced platinum resistance in ovarian cancer, and increased HOTAIR levels were observed in recurrent platinum-resistant ovarian tumors vs. primary ovarian tumors. To investigate the role of HOTAIR during DNA damage induced by platinum, we monitored double-strand breaks and show that HOTAIR expression results in sustained activation of DNA damage response after platinum treatment. We demonstrate that ectopic expression of HOTAIR induces NF-κB activation during DNA damage response and MMP-9 and IL-6 expression, both key NF-κB target genes. We show that HOTAIR regulates activation of NF-κB by decreasing Iκ-Bα (NF-κB inhibitor) and establish that by inducing prolonged NF-κB activation and expression of NF-κB target genes during DNA damage, HOTAIR plays a critical role in cellular senescence and platinum sensitivity. Our findings suggest that
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