298 research outputs found

    Newly identified YSO candidates towards the LDN 1188

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    We present an analysis of Young Stellar Object (YSO) candidates towards the LDN 1188 molecular cloud. The YSO candidates were selected from the WISE all-sky catalogue, based on a statistical method. We found 601 candidates in the region, and classified them as Class I, Flat and Class II YSOs. Groups were identified and described with the Minimal Spanning Tree (MST) method. Previously identified molecular cores show evidence of ongoing star formation at different stages throughout the cloud complex.Comment: 4 pages, 4 figures, 2 table

    Search for signatures of dust in the Pluto-Charon system using Herschel/PACS observations

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    In this letter we explore the environment of Pluto and Charon in the far infrared with the main aim to identify the signs of any possible dust ring, should it exist in the system. Our study is based on observations performed at 70 um with the PACS instrument onboard the Herschel Space Observatory at 9 epochs between March 14 and 19, 2012. The far-infrared images of the Pluto-Charon system are compared to those of the point spread function (PSF) reference quasar 3C454.3. The deviation between the observed Pluto-Charon and reference PSFs are less then 1 sigma indicating that clear evidence for an extended dust ring around the system was not found. Our method is capable of detecting a hypothetical ring with a total flux of ~3.3 mJy at a distance of ~153 000 km (~8.2 Pluto-Charon distances) from the system barycentre. We place upper limits on the total disk mass and on the column density in a reasonable disk configuration and analyse the hazard during the flyby of NASAs New Horizons in July 2015. This realistic model configuration predicts a column density of 8.7x10^(-10) gcm^(-2) along the path of the probe and an impactor mass of 8.7x10^(-5) g.Comment: 10 pages, 4 figures, 2 table

    Légköri aeroszol vízoldható szerves alkotóinak kémiai jellemzése = Chemical characterization of water Soluble Components of the Atmospheric Aerosol

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    1. Az atmoszférikus aeroszolban előforduló vízoldható szerves komponensek (WSOC) felületaktivitásának polarográfiás vizsgálata - Az ún. finom aeroszol frakció WSOC anyagai eltérő, évszakok szerint változó polarográfiás maximumelnyomó hatást mutattak. - Polarográfiás maximumelnyomás vizsgálatára vonatkozó kísérleteink megerősítették a feltevést, miszerint, az aeroszol oldott szerves anyaga felületaktivitással bír. - Modellvegyületekkel végzett kísérleteink igazolták, hogy a legintenzívebb maximumelnyomó vegyületek a fulvósavakhoz hasonló szerkezettel rendelkezhetnek. A WSOC komponensek között tehát valószínűsíthető huminszerű anyagok (HULIS) előfordulása. 2. A WSOC fémmegkötő kapacitásának és a fém – WSOC komplex stabilitási állandójának meghatározása - Stripping voltammetriás módszert dolgoztunk ki a Cu(II)-WSOC komplexek egyensúlyi állandójának és a WSOC komplexképző kapacitását meghatározására. - Eredményeink szerint az aeroszol WSOC egyes komponensei pH 7.8 oldatban az ismert kelátképző vegyületekhez (pl. EDTA) hasonló erősséggel kötik meg a Cu(II)-ionokat (logK ~ 16). - A WSOC látszólagos komplexképző kapacitását pH 7.8 oldatban 6.6 – 39 nmol Cu(II) / mgC-nek találtuk. Ezen kapacitásértékek nagyságrendileg összevethetőek az esővízben, illetve felszíni vizekben mért irodalmi adatokkal. | 1. Polarographic study of the surface activity of the water soluble organic components (WSOC) of the atmospheric aerosols. - The WSOC components of the so called fine aerosol fraction showed a well defined reproducible suppression activity of the poarographic current maxima. - A study of the effect of maximum suppression proved the hypothesis concerning the surface activity of the WSOC components which plays an important role in the formation of the cloud condensation nuclei and the rain drops. - Study of the maximum suppression effect of several model compounds revealed that the most efficient maximum suppressors are structurally similar to the fulvic acid. Consequently, the occurrence of humic like substances (HULIS) among the WSOC components is very likely. 2. Determination of the metal binding capacity of the WSOC and the apparent binding constant of the metal – WSOC associates. - A stripping voltammetric method was developed for the determination of the binding constant of the Cu(II) – WSOC associates and for the Cu(II) complexing capacity of the WSOC. - Results (obtained at pH=7.8) indicate that certain components of the WSOC bind the metal almost as strongly (logK ~ 16) as the common complexing ligands like e.g. the EDTA. - The apparent complexing capacity of the WSOC (at pH=7.8) changed from 6.6 – 39 nmol Cu/mgC. These capacity values are well compared with the published complexing capacity data obtained for rain and surface waters

    The complex role of physical exercise and reactive oxygen species on brain

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    AbstractReactive oxygen species (ROS) are continuously generated during aerobic metabolism and at moderate level. They play a role in redox signaling, but in significant concentration they cause oxidative damage and neurodegeneration. Because of the enhanced sensitivity of brain to ROS, it is especially important to maintain the normal redox state in different types of neuron cells. In last decade it became clear that regular exercise beneficially affects brain function, and can play an important preventive and therapeutic role in stroke, Alzheimer, and Parkinson diseases. The effects of exercise appear to be very complex and could include neurogenesis via neurotrophic factors, increased capillariszation, decreased oxidative damage, and increased proteolytic degradation by proteasome and neprilysin. Data from our and other laboratories indicate that exercise-induced modulation of ROS levels plays a role in the protein content and expression of brain-derived neurotrophic factor, tyrosine-related kinase B (TrkB), and cAMP response element binding protein, resulting in better function and increased neurogenesis. Therefore, it appears that exercise-induced modulation of the redox state is an important means, by which exercise benefits brain function, increases the resistance against oxidative stress, facilitates recovery from oxidative stress, and attenuates age-associated decline in cognition

    Critical point analysis and biocide treatment in a microbiologically contaminated water purification system of a power plant

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    Many industries use ultrapure water (UPW) for their operation. In spite of purification efforts, microbial contaminations are the major cause of manufacturing problems in these systems. In our experiments, the water purification system of a power plant was investigated: the microbiologically critical points of the ultrapure water purification system were located by checking the number and diversity of bacteria to determine the optimum operational unit for chemical intervention: the most contaminated site was the mixed-bed ion-exchange resin containing unit. Biocides were tested against bacteria previously isolated from the same system; effect of biocides was checked also in laboratory model systems, and based on the results, a biocide treatment was carried out in the mixed-bed ion-exchange resin columns of the working power plant. Kathon WT was the most effective from the studied chemicals, being effective already in low concentration against most studied microorganisms. In case of the handling of the mixed-bed ion-exchange resin, 8-h treatment with 25ppm biocide concentration was effective. Following the treatment, the quality of the produced UPW met the standards (specific electric conductivity was<1.0x10(-3)mu Scm(-1) at 25 degrees C) and water production capacity increased; moreover, the run-down time of the mixed-bed ion-exchange resin significantly grew

    Mitochondrial biogenesis-associated factors underlie the magnitude of response to aerobic endurance training in rats

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    Trainability is important in elite sport and in recreational physical activity, and the wide range for response to training is largely dependent on genotype. In this study, we compare a newly developed rat model system selectively bred for low and high gain in running distance from aerobic training to test whether genetic segregation for trainability associates with differences in factors associated with mitochondrial biogenesis. Low response trainer (LRT) and high response trainer (HRT) rats from generation 11 of artificial selection were trained five times a week, 30 min per day for 3 months at 70 % VO2max to study the mitochondrial molecular background of trainability. As expected, we found significant differential for the gain in running distance between LRT and HRT groups as a result of training. However, the changes in VO2max, COX-4, redox homeostasis associated markers (reactive oxygen species (ROS)), silent mating-type information regulation 2 homolog (SIRT1), NAD+/NADH ratio, proteasome (R2 subunit), and mitochondrial network related proteins such as mitochondrial fission protein 1 (Fis1) and mitochondrial fusion protein (Mfn1) suggest that these markers are not strongly involved in the differences in trainability between LRT and HRT. On the other hand, according to our results, we discovered that differences in basal activity of AMP-activated protein kinase alpha (AMPKα) and differential changes in aerobic exercise-induced responses of citrate synthase, carbonylated protein, peroxisome proliferator-activated receptor gamma coactivator-1α (PGC1-α), nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), and Lon protease limit trainability between these selected lines. From this, we conclude that mitochondrial biogenesis-associated factors adapt differently to aerobic exercise training in training sensitive and training resistant rats

    Enhanced expression of the stemness-related factors OCT4, SOX15 and TWIST1 in ectopic endometrium of endometriosis patients

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    Abstract Background Current evidence suggests that endometrial-derived stem cells, spilled in the peritoneal cavity via retrograde menstruation, are key players in the establishment of endometriotic lesions. The aim of this study was to determine the presence and distribution of the stemness-related factors OCT4, SOX15, TWIST1 and DCAMLK1 in women with and without endometriosis. Methods Immunohistochemical analysis was used to determine stromal and epithelial expression of OCT4, SOX15, TWIST1 and DCAMLK1 in endometriosis patient (EP) endometrium (n = 69) and endometriotic tissue (n = 90) and in control endometrium (n = 50). Quantitative Real-Time PCR of OCT4, SOX15 TWIST1 and DCAMLK1 was performed in paired samples of EP endometrium and endometriotic tissue. Co-immunofluorescence staining was performed for OCT4 and SOX15. For statistical analyses we used unpaired t-test, Fisher combination test and Spearman test. For paired analyses, paired t-test and McNemar test were used. Results We detected a significant correlation between the expression of the established stem cell marker OCT4 and the stemness-related markers SOX15 (p < 0.001) and TWIST1 (p = 0.002) but not DCAMLK1. We showed a colocalization of SOX15 and OCT4 in epithelial and stromal cells of endometriotic tissue by coimmunofluorescence. A concordant expression of OCT4 and SOX15 in the same sample was observed in epithelial cells of the endometriotic tissue (71.7%). The expression of stemness-related factors was not associated with proliferative or secretory phase of the menstrual cycle in endometriosis patients but was found to be differentially expressed during the menstrual cycle in the control group. Increased expression of epithelial OCT4, SOX15 and TWIST1 was detected in endometriotic tissue compared to EP endometrium in paired (p = 0.021, p < 0.001 and p < 0.001) and unpaired analysis (p = 0.040, p < 0.001 and p = 0.001). Conclusion Our findings support the hypothesis that upregulation of stem cell-related factors contribute to the establishment of endometriotic lesions. Trial registration The study was approved by the institutional review board (545/2010 on 6th of May 2014) of the Medical University of Vienna ( http://ethikkommission.meduniwien.ac.at/fileadmin/ethik/media/dokumente/register/alle_2010.pdf )

    SPIRE Point Source Catalog Explanatory Supplement

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    The Spectral and Photometric Imaging Receiver (SPIRE) was launched as one of the scientific instruments on board of the space observatory Herschel. The SPIRE photometer opened up an entirely new window in the Submillimeter domain for large scale mapping, that up to then was very difficult to observe. There are already several catalogs that were produced by individual Herschel science projects. Yet, we estimate that the objects of only a fraction of these maps will ever be systematically extracted and published by the science teams that originally proposed the observations. The SPIRE instrument performed its standard photometric observations in an optically very stable configuration, only moving the telescope across the sky, with variations in its configuration parameters limited to scan speed and sampling rate. This and the scarcity of features in the data that require special processing steps made this dataset very attractive for producing an expert reduced catalog of point sources that is being described in this document. The Catalog was extracted from a total of 6878 unmodified SPIRE scan map observations. The photometry was obtained by a systematic and homogeneous source extraction procedure, followed by a rigorous quality check that emphasized reliability over completeness. Having to exclude regions affected by strong Galactic emission, that pushed the limits of the four source extraction methods that were used, this catalog is aimed primarily at the extragalactic community. The result can serve as a pathfinder for ALMA and other Submillimeter and Far-Infrared facilities. 1,693,718 sources are included in the final catalog, splitting into 950688, 524734, 218296 objects for the 250\mu m, 350\mu m, and 500\mu m bands, respectively. The catalog comes with well characterized environments, reliability, completeness, and accuracies, that single programs typically cannot provide

    Biomassza hasznosítás kémiai alapfolyamatainak tanulmányozása = Study of fundamental chemical processes of biomass utilization

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    (1) Biomassza anyagok széles skáláját vizsgáltuk termikus módszerekkel. A hőbomlásról, az égési folyamatokról, és az elgázosításról nyertünk ismereteket, valamint hozzájárultunk egyes biomassza-hasznosítási eljárások során lejátszódó folyamatok mélyebb megértéséhez. Olyan reakciókinetikai modelleket alkalmaztunk, ill. dolgoztunk ki, melyek nagyobb mérési sorozatokon, a kísérleti körülmények széles tartományában írják le a vizsgált termikus reakciókat, és tükrözték a vizsgált minták szerkezetének és felépítésének komplikált voltát. (2) Bioetanol gyártás tématerületen öt szubsztráton (gőzrobbantással előkezelt cukorcirok bagasz, kender, kender pozdorja és kontrollként két modell szubsztrát) vizsgáltuk a Tween 80 és a PEG 4000 adalékanyagok hatását különböző hőmérsékleteken. Kísérleteinkben kimutattuk, hogy ezen adalékanyagok hozzáadásával növelhető a szubsztrátok enzimes lebontásának hatékonysága. Cukorcirok alapú technológiák anyag- és energiamérlegének modellezésével igazoltuk, hogy a teljes termelési időszak alatt biztosítani lehet az üzem hőigényét a melléktermékek felhasználásával. (3) Bioszorbenseket állítottunk elő lignocellulóz típusú agro-hulladékokból (kipréselt repce pellet, keményítőmentes búzamag) kémiai módosításokkal, amelyek így alkalmasak voltak szervetlen illetve szerves anyagok (szennyezők) megkötésére. | (1) A wide range of biomass materials have been studied by thermal analysis and related methods. New knowledge was obtained on the thermal decomposition, combustion processes and gasification by CO2. The work contributed to a deeper understanding of the reactions taking place during various biomass utilization methods. Such reaction kinetic models were employed and developed that reflected the complexity of the studied materials and described larger series of experiments at various experimental conditions. (2) In the field of bioethanol production the effect of Tween 80 and PEG 4000 additives on five substrates (steam pretreated sweet sorghum bagasse, hemp, hemp hurds and two model substrates) was investigated at various temperatures. It was proven that these additives could increase the efficiency of enzymatic digestibility of these substrates. By modeling the mass and energy balances of sweet sorghum based technologies it was verified that the heat demand of the process can be covered during the whole production period by utilizing the by-products. (3) Biosorbents were prepared from lignocellulosic agricultural wastes (pressed rape seed pellet, starch free wheat seed) by chemical modifications. The products were suitable to bond organic and inorganic pollutants
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