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    Synthesis and biological activity of some heterocyclic compounds contains N-benzylidene heterocycle and beta-lactam moiety

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    A number of N-benzylidene heterocycle derivatives have been synthesized and their antibacterial activities tested. The new chemical structures synthesized compounds were verified on the basis of spectral and elemental methods of analyses.the antimicrobial activity of the compounds was done by disc diffusion method We synthesized two different types of compounds, a combination of compounds based on the structure of isatin and other compounds based on the structure of thiazole. Synthesis of thiazole was performed using green chemistry method and a three-step reaction was used in the synthesis of isatin compounds. We used the Stoell-Becker method to synthesize compounds based on the isatin structure. The synthesized product was characterized by its physical properties, melting point, TLC and then subjected to the in vitro antibacterial activities against gram-positive and gram-negative strains of microbe

    The half-lives of biological activity of some pesticides in water

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    In the absence of analytical methods, the half-lives of biological activity of pesticides can be estimated by bioassays. To determine the half-lives of biological acivity of pesticides to fish, static bioassays were conducted in the laboratory with ten different formulations of pesticides using Labeo rohita as a bio-indicator. The half-lives of biological activity for ten different pesticides in soft water at pH 7.5 and 27°C, ranged from 4.6 days to 11.8 days. The half-life of biological activity of Sumithion 50% EC was only 4.6 days. In contrast, Dimecron 50% EC degraded very slowly and its half-life of biological activity on L. rohita was about 11.8 days. Sumithion 50% EC, Padan 50% SP, EPN 45% EC, Diazinon 40% EC and Diazinon 10 G degraded in less than five to seven days indicating that these pesticides are desirable for rice-fish culture. Contamination by pesticides with long-term residual toxicity in waters may eventually cause high levels of fish mortality

    Initial soil structural development under different types of vegetation

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    In September 2007, undisturbed soil cores were taken from experimental fields in The Netherlands and in Northern Sweden that had been under different types of vegetation during four years. From these cores, thin sections were prepared to study the initial soil structural development, changes in organic matter distribution and soil biological activity in relation to plant species growing on the plots. In the Swedish samples, differences between plots with Poa pratensis and Phleum pratense were striking. The Poa plot showed more filled biological burrows, more rounded soil aggregates and also the amount of fine disperse organic matter seemed higher, whereas under Phleum the individual mineral grains more often showed a thin coating of very fine organic matter. Plots with Trifolium repens showed a slightly less pronounced development when compared to the Poa plots. The plots of Trifolium pratense plots and the mixed plot showed highest amounts of biological activity and soil structural development. The samples taken from the clay soils from The Netherlands showed similar biological activity under pure Lolium perenne and binary mixtures of L. perenne with the legumes T. repens, T. pratense and Medicago sativa from a trial that was not fertilized with N. A high activity of Lumbricus festi was shown by common excremental pellets in channels. In contrast, under Achillea millefolium in an adjacent N fertilised experiment, this activity was completely absent

    Biological research of Grabia River - fifty years of activity

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    Grabia, a small still close to natural conditions lowland river, has been an object of special interest for Łódź hydrobiologists for more than 50 years. Over 100 scientific papers and over 100 master theses were produced in the Faculty of Biology and Environmental Protection University of Łódź. The initiator was Prof.L.K. Pawłowski who spent many years conducting research into the river. The ground and the first research objective was to recognize the fauna diversity. The checklist encompass almost 1000 invertebrate and 24 fish species. Taxonomy, biology and ecology of various taxa have made for many decades an essential trend of scientific activity. Special attention was dedicated to rotifers, leeches, branchiobdellids, snails and bivalves, gammarids and copepods as well as aquatic insects, fish and also diatoms. Some aspects of zoobenthos and Zooplankton communities ecology was the subject of 13 Ph.D.theses. The river with its rich animal and plant communities was also the subject of dynamics of river ecosystem research. The study on the structure of invertebrate assemblages on the background of habitat diversity has been recently conducted. The model may be treealed as a reference to the restoration of Europaean rivers and their valleys.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 dofinansowane zostało ze środków MNiSW w ramach działalności upowszechniającej naukę

    Postulates on electromagnetic activity in biological systems and cancer

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    A framework of postulates is formulated to define the existence, nature, and function of a coherent state far from thermodynamic equilibrium in biological systems as an essential condition for the existence of life. This state is excited and sustained by energy supply. Mitochondria producing small packets of energy in the form of adenosine and guanosine triphosphate and strong static electric field around them form boundary elements between biochemical-genetic and physical processes. The transformation mechanism of chemical energy into useful work for biological needs and the excitation of the coherent state far from thermodynamic equilibrium are fundamental problems. The exceptional electrical polarity of biological objects and long-range interactions suggest a basic role of the endogenous electromagnetic field generated by living cells. The formulated postulates encompass generation, properties and function of the electromagnetic field connected with biological activity and its pathological deviations. Excited longitudinal polar oscillations in microtubules in eukaryotic cells generate the endogenous electromagnetic field. The metabolic activity of mitochondria connected with water ordering forms conditions for excitation. The electrodynamic field plays an important role in the establishment of coherence, directional transport, organization of morphological structures, interactions, information transfer, and brain activity. An overview of experimental results and physical models supporting the postulates is included. The existence of the endogenous biological electromagnetic field, its generation by microtubules and supporting effects produced by mitochondria have a reasonable experimental foundation. Cancer transformation is a pathological reduction of the coherent energy state far from thermodynamic equilibrium. Malignancy, i.e. local invasion and metastasis, is a direct consequence of mitochondrial dysfunction, disturbed microtubule polar oscillations and the generated electromagnetic field

    Recent advances in the total synthesis of agelastatins

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    Agelastatins represent an important family of marine alkaloids in terms of both exceptional biological activity and intriguing chemical structure. In this article, the isolation and biological activity of agelastatins are reviewed, and proposed biosynthetic pathways are summarized. The main focus is given to comparative evaluation of recent total syntheses, mainly of agelastatin A. To date, this has been accomplished by 11 research groups. Their synthetic routes are analyzed and summarized, with a view to furnishing the reader with insight into different strategic design approaches to assembly of a densely functionalized and compact structure

    EEG theta and Mu oscillations during perception of human and robot actions.

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    The perception of others' actions supports important skills such as communication, intention understanding, and empathy. Are mechanisms of action processing in the human brain specifically tuned to process biological agents? Humanoid robots can perform recognizable actions, but can look and move differently from humans, and as such, can be used in experiments to address such questions. Here, we recorded EEG as participants viewed actions performed by three agents. In the Human condition, the agent had biological appearance and motion. The other two conditions featured a state-of-the-art robot in two different appearances: Android, which had biological appearance but mechanical motion, and Robot, which had mechanical appearance and motion. We explored whether sensorimotor mu (8-13 Hz) and frontal theta (4-8 Hz) activity exhibited selectivity for biological entities, in particular for whether the visual appearance and/or the motion of the observed agent was biological. Sensorimotor mu suppression has been linked to the motor simulation aspect of action processing (and the human mirror neuron system, MNS), and frontal theta to semantic and memory-related aspects. For all three agents, action observation induced significant attenuation in the power of mu oscillations, with no difference between agents. Thus, mu suppression, considered an index of MNS activity, does not appear to be selective for biological agents. Observation of the Robot resulted in greater frontal theta activity compared to the Android and the Human, whereas the latter two did not differ from each other. Frontal theta thus appears to be sensitive to visual appearance, suggesting agents that are not sufficiently biological in appearance may result in greater memory processing demands for the observer. Studies combining robotics and neuroscience such as this one can allow us to explore neural basis of action processing on the one hand, and inform the design of social robots on the other

    Synthetic chemistry and biological activity of pentafluorosulphanyl (SF5) organic molecules

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    Acknowledgements We thank the European Commission for financial support (Industry Academia Partnerships and Pathways project “PET BRAIN”, Contract No 251482). S.A. thanks the Northern Research Partnership (www.northscotland-research.ac.uk/) and Pharmaness (www.pharmaness.it) for co-funding a PhD studentship.Peer reviewedPostprin
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