145 research outputs found

    Distribution of micro-amounts of europium in the two-phase water–HCl–nitrobenzene–N,N’-dimethyl-N,N’-diphenyl-2,6-di-picolinamide–hydrogen dicarbollylcobaltate extraction system

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    Extraction of micro-amounts of europium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of N,N’-dimethyl-N,N’-diphenyl-2,6-dipicolinamide (MePhDPA, L) was investigated. The equilibrium data were explained assuming that the species HL+, HL+2, HL3+2 and HL3+3 are extracted into the organic phase. The values of the extraction and stability constants of the species in nitrobenzene saturated with water were determined

    Satellite Technologies in Monitoring of Ecosystems

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    The article provides a description of modern geodetic devices, which are used to solve several problems connected with environmental and hydraulic engineering. In particular, a non-conventional method of area measurement for ecosystems monitoring, which involves the usage of satellite navigation devices, is considered. Nowadays electronic tachymeters, digital levelling instruments, laser scanning systems and satellite systems are widely used for implementation of geodetic engineering works. In full extent it could be also applied to different environmental and hydraulic engineering problems solution.The satellite navigators, especially with GPS+GLONASS system support, are the promising alternative to handle different planimetric tasks, particularly, water surface and drainage area measurement. The paper presents an analysis of the results of research carried out in 2012-2014 years and comparison of them with the new field data. Moreover the obtained results are compared with the theoretical values of quadrates’ areas and the dependence of the relative accuracy versus land plot area is built.Based on a practical research, the accuracy of the method is being estimated. The analysis of different measuring conditions and factors, regarding their effect on accuracy, is made. The suitable areas, where the method could be used, are mentioned. Particularly, the possibility of water surface and drainage area measuring is examined with the usage of previous theoretical base. The paper presents an analysis of the results of research carried out in 2012-2014 years and comparison of them with the new field data. Moreover the obtained results are compared with the theoretical values of quadrates’ areas and the dependence of the relative accuracy versus land plot area is built.Based on a practical research, the accuracy of the method is being estimated. The analysis of different measuring conditions and factors, regarding their effect on accuracy, is made. The suitable areas, where the method could be used, are mentioned. Particularly, the possibility of water surface and drainage area measuring is examined with the usage of previous theoretical base.

    The Study of Species Diversity of Fungi-Litaliano Allocated with Samples of Cement Composites Containing Limestones of Different Origin and Subjected to Aging at Conditions of the Black Sea Climate

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    The article presents the results of a study of the decay resistance of cement composites filled with carbonate and silicate rocks. The investigated composites exhibited for one year under conditions of the black sea climate in the open air under a canopy of sea coast and sea water. Species and generic diversity of fungi-Litvinov on the samples, depending on the origin of carbonate rocks and the conditions of aging. By results of researches it is stated that fouling, the number of species in the community, as well as specific species composition to a greater extent depends on the operating conditions of the material, and to a lesser extent on the mineral composition of the filler. The authors give a classification of biological agents- destructors of building materials in their preferred conditions of growth that may be promising for the further development of approaches to deal with them. Installed rational compositions of concrete composites derived from limestones of different origin

    Mutations in the m-AAA proteases AFG3L2 and SPG7 are causing isolated dominant optic atrophy.

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    OBJECTIVE: To improve the genetic diagnosis of dominant optic atrophy (DOA), the most frequently inherited optic nerve disease, and infer genotype-phenotype correlations. METHODS: Exonic sequences of 22 genes were screened by new-generation sequencing in patients with DOA who were investigated for ophthalmology, neurology, and brain MRI. RESULTS: We identified 7 and 8 new heterozygous pathogenic variants in SPG7 and AFG3L2. Both genes encode for mitochondrial matricial AAA (m-AAA) proteases, initially involved in recessive hereditary spastic paraplegia type 7 (HSP7) and dominant spinocerebellar ataxia 28 (SCA28), respectively. Notably, variants in AFG3L2 that result in DOA are located in different domains to those reported in SCA28, which likely explains the lack of clinical overlap between these 2 phenotypic manifestations. In comparison, the SPG7 variants identified in DOA are interspersed among those responsible for HSP7 in which optic neuropathy has previously been reported. CONCLUSIONS: Our results position SPG7 and AFG3L2 as candidate genes to be screened in DOA and indicate that regulation of mitochondrial protein homeostasis and maturation by m-AAA proteases are crucial for the maintenance of optic nerve physiology

    Ophthalmology

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    To characterize the genotypic and phenotypic spectrum of foveal hypoplasia (FH). Multicenter, observational study. A total of 907 patients with a confirmed molecular diagnosis of albinism, PAX6, SLC38A8, FRMD7, AHR, or achromatopsia from 12 centers in 9 countries (n = 523) or extracted from publicly available datasets from previously reported literature (n = 384). Individuals with a confirmed molecular diagnosis and availability of foveal OCT scans were identified from 12 centers or from the literature between January 2011 and March 2021. A genetic diagnosis was confirmed by sequence analysis. Grading of FH was derived from OCT scans. Grade of FH, presence or absence of photoreceptor specialization (PRS+ vs. PRS-), molecular diagnosis, and visual acuity (VA). The most common genetic etiology for typical FH in our cohort was albinism (67.5%), followed by PAX6 (21.8%), SLC38A8 (6.8%), and FRMD7 (3.5%) variants. AHR variants were rare (0.4%). Atypical FH was seen in 67.4% of achromatopsia cases. Atypical FH in achromatopsia had significantly worse VA than typical FH (P < 0.0001). There was a significant difference in the spectrum of FH grades based on the molecular diagnosis (chi-square = 60.4, P < 0.0001). All SLC38A8 cases were PRS- (P = 0.003), whereas all FRMD7 cases were PRS+ (P < 0.0001). Analysis of albinism subtypes revealed a significant difference in the grade of FH (chi-square = 31.4, P < 0.0001) and VA (P = 0.0003) between oculocutaneous albinism (OCA) compared with ocular albinism (OA) and Hermansky-Pudlak syndrome (HPS). Ocular albinism and HPS demonstrated higher grades of FH and worse VA than OCA. There was a significant difference (P < 0.0001) in VA between FRMD7 variants compared with other diagnoses associated with FH. We characterized the phenotypic and genotypic spectrum of FH. Atypical FH is associated with a worse prognosis than all other forms of FH. In typical FH, our data suggest that arrested retinal development occurs earlier in SLC38A8, OA, HPS, and AHR variants and later in FRMD7 variants. The defined time period of foveal developmental arrest for OCA and PAX6 variants seems to demonstrate more variability. Our findings provide mechanistic insight into disorders associated with FH and have significant prognostic and diagnostic value

    Potential of Core-Collapse Supernova Neutrino Detection at JUNO

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    JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

    Detection of the Diffuse Supernova Neutrino Background with JUNO

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    As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

    Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

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    Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30M⊙M_{\odot} for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

    Long-range angular correlations on the near and away side in p&#8211;Pb collisions at

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    Revisions to the Classification, Nomenclature, and Diversity of Eukaryotes

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    This revision of the classification of eukaryotes follows that of Adl et al., 2012 [J. Euk. Microbiol. 59(5)] and retains an emphasis on protists. Changes since have improved the resolution of many nodes in phylogenetic analyses. For some clades even families are being clearly resolved. As we had predicted, environmental sampling in the intervening years has massively increased the genetic information at hand. Consequently, we have discovered novel clades, exciting new genera, and uncovered a massive species level diversity beyond the morphological species descriptions. Several clades known from environmental samples only have found their home. Sampling soils, deeper marine waters, and the deep sea will continue to fill us with surprises. The main changes in this revision are the confirmation that eukaryotes form at least two domains, the loss of monophyly in the Exavata, robust support for the Haptista and Cryptista. We provide suggested primer sets for DNA sequences from environmental samples that are effective for each clade. We have provided a guide to trophic functional guilds in an appendix, to facilitate the interpretation of environmental samples. This revision of the classification of eukaryotes updates that of the International Society of Protistologists (Adl et al., 2012). Since then, there has been a massive increase in DNA sequence information of phylogenetic relevance from environmental samples. We now have a much better sense of the undescribed biodiversity in our environment (Pawlowski et al., 2012; de Vargas et al., 2015). While significant, it still remains a partial estimation as several continents and soils in general are poorly sampled, and the deeper ocean is hard to reach. This new data clarified phylogenetic relationships and the new information is incorporated in this revision
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