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Mineralized quartz veins within Phanerozoic orogenic belts provide important insights into fluid source and transport, source(s) of S, and genetic implications for ore deposit formation. Here, investigations on mineralized veins hosted by the Hog Mountain tonalite, southernmost Appalachians, were performed using scanned electron microscopy, microprobe analysis, and secondary ion mass spectrometry.The small, reduced Hog Mountain tonalite hosts three different mineralized vein types dominated by Au-bearing quartz veins with a simple base metal sulfide assemblage and spatially associated Au phases (electrum > native gold > maldonite) with Bi phases (native bismuth > unnamed Bi3Te ≈ hedleyite > bismuthinite). In contrast, barren to low-grade arsenopyrite and sphalerite-pyrite-arsenopyrite-galena-chalcopyrite (Zn-Fe-As-Pb-Cu) veinlets are rare. Base metal sulfides are stoichiometrically homogeneous with the exception of sphalerite and galena that have noticeable enrichments in Fe and Cd, and Bi and Ag, respectively. Trace element concentrations (Au, Ag, Bi, Te, Se, and transition metals) in major and minor base metal sulfides are generally low. In situ sulfur isotope analyses on base metal sulfides from different vein types show two distinct populations: (1) δ34Ssulfide = 12.9 ± 1.4‰ in low-grade arsenopyrite and Zn-Fe-As-Pb-Cu veinlets and (2) δ34Ssulfide = 7.7 ± 0.9‰ in mineralized quartz veins.Based on mineral chemistry, two fluid phases were responsible for metal deposition at Hog Mountain. Fluid phase I with low-soluble Au formed rare, barren to low-grade arsenopyrite and Zn-Fe-As-Pb-Cu veinlets from highly acidic, relatively high temperature fluid with moderate ƒS2 and variable ƒO2. In contrast, a reduced, near-neutral, low ƒS2 fluid phase II had higher soluble Au concentrations and created the dominant Au-bearing quartz veins in which Au was deposited via scavenging by Bi melts syngenetic at lower temperatures. Isotopic modeling shows that both fluid phases sourced their S from the metasedimentary rocks hosting the tonalite and adjacent, coeval gold deposits, with the tonalite contributing some S to fluid phase II, resulting in lower δ34S values. Our results are consistent with mineral assemblage, mineral chemistry, and sulfur source(s) from other intrusion-hosted Phanerozoic orogenic gold deposits and support the syngenetic Au scavenging model by Bi melts as a viable Au deposition process in orogenic gold deposits.

The importance and advantages of the hybrid approach developed within the TAIGA project for studying the high-energy section of the spectrum of gamma radiation in the Universe are discussed. The pilot complex of the TAIGA gamma observatory with an area of 1 km $${}^{2}$$ is briefly described along with the lines of its development, and the first results obtained on this basis are given.

Work is currently under way in the Tunka Valley, 50 km from Lake Baikal, to create the TAIGA gamma observatory for studying gamma radiation and cosmic ray fluxes in the 1013–1018 eV range of energies. To detect gamma rays with energies above tens of TeV, a hybrid method of detecting showers is implemented. It is based on data obtained by the TAIGA Imaging Atmospheric Cherenkov Telescope (IACT) and the wide-angle TAIGA-HiSCORE array. The preliminary results from processing the telescope’s data for the low-energy region (>2–3 TeV) are presented. Joint events with energy more than 50 TeV are analyzed and compared to Monte Carlo calculations.

The TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) experiment aims at observing gamma-rays in the energy range from 1 TeV to several 100 TeV. The operation of the observatory is based on a new hybrid approach that combines imaging air Cherenkov telescopes (IACTs) and wide-angle Cherenkov detectors (TAIGA-HiSCORE) for measuring times of extensive air shower (EAS) light front arrival. Monte Carlo simulations are compared to real data to determine the performance of the detector setup. Dedicated software and algorithms are described, model parameters are given, and an overview of the current status of model-based performance studies is presented.

The Tunka-133 Cherenkov complex for recording extensive air showers (EAS) collected data over seven winters from 2009 to 2017. The differential energy spectra of all particles was acquired in the 6 × 1015–3 × 1018 eV range of energies over 2175 h. The TAIGA-HiSCORE complex is continually being expanded and upgraded. Data acquired by 30 first-line stations over 35 days during the period 2017–2018 is analyzed in this work. As at the Tunka-133 setup, the primary particle energies above 1015 eV are measured using the density of the Cherenkov light flux at a distance of 200 m from a shower’s axis. Data on lower energies are collected by determining the energy of the light flux near a shower’s axis. This results in a spectrum of 2 × 1014–1017 eV. The combined spectrum for the two systems covers a range of 2 × 1014–2 × 1018 eV.

The TAIGA astroparticle observatory is progressing with the deployment of new detector stations. The Tunka-Grande — scintillation counter array of the observatory expands with the new TAIGA-Muon stations. Several simulation studies were conducted for optimisation of the new station positioning and performance. Extensive air showers induced by gamma quanta or a proton in the range from 100 TeV to 1 PeV at a zenith angle of 0° were used for these studies. Based on the developed simulation, the capabilities of identification of high energy extensive air showers were studied. The soil thickness, the detector and station positions, the lowest measurable energy range of the cosmic rays, and different methods of air shower identification were investigated.

The TAIGA experiment in Tunka valley is expanding the present scintillation detector array with new TAIGA-Muon detector stations. A simulation model was developed for optimization of the layout of the new stations and study of the identification performance of the array. The extensive air showers (EASs) were simulated with the CORSIKA simulation tool, and the detector response was simulated with the GEANT4 package. EASs induced by gamma quanta or protons in the energy range from 1 PeV to 10 PeV and the zenith angle range from 0° to 45°, are used for these studies. For the identification of high energy extensive air showers, a method based on a neural network was suggested. With this method, the proton identification efficiency is more than 90%, while the gamma identification efficiency not less than 50%.

The TAIGA experiment in the Tunka valley near Lake Baikal is planning an extension with new TAIGA-Muon scintillation detector stations. The main purpose of TAIGA is gamma-ray astronomy in the TeV to PeV energy range and cosmic ray physics. The purpose of the Taiga-Muon detectors is to measure the muon component of air showers for improving cosmic ray composition measurements as well as gamma–hadron separation above 100 TeV. Monte Carlo simulations of the experiment are done with the software packages CORSIKA and GEANT4. Extensive air showers of primary particles in the energy range 100–3000 TeV are created with CORSIKA. The trigger efficiency is calculated and used for optimization. The suppression factor of hadronic showers versus electromagnetic showers is studied, leading to an optimum depth of soil absorber (2 m), at the lowest energy range. Data on the identification efficiency for primary gamma-quanta and proton events are presented as well as the suppression factor.

This paper presents new geochronological and geochemical (whole-rock major and trace elements and Sr–Nd–Pb isotopes) data on intrusive rocks exposed in the Qiongduojiang area, the northern part of the Tethyan Himalaya. The Qiongduojiang intrusive rocks are mainly composed of mafic rocks (diabase and gabbro) with subordinate felsic rocks (monzonite), indicating bimodal component characteristics. In zircon U-Pb dating of monzonite, diabase and gabbro samples, the weighted mean ages of magma emplacement were determined to be 230.5 ± 2.9 Ma to 227.4 ± 4.7 Ma, showing Middle–Late Triassic magmatic activity in the northern part of the Himalayan belt. The monzonitic rocks share most of the geochemical features of A-type granites, and their Nd isotopic compositions are consistent with those of coeval diabase rocks. This suggests that they are likely generated by mantle-derived magmas, which had assimilated significant amounts of continental crust. The gabbro samples exhibit the geochemical composition of ocean island basalt (OIB) features and therefore assumingly originate from a depleted mantle source with insignificant crustal contamination. In contrast, the diabase samples display enriched mid-ocean ridge basalt (E-MORB) features and were derived from spinel bearing peridotite that was metasomatised by OIB-like components with limited crustal contamination. The Qiongduojiang bimodal magmas can be considered as the products of the opening of the Neo-Tethyan ocean. Considering the magmatic petrology, paleomagnetism and paleontology data, we further propose that the Neo-Tethyan ocean began opening before ~230 Ma.

It is planned that new TAIGA-Muon detectors will complement the existing Tunka-GRANDE facility of scintillation detectors of the TAIGA gamma-observatory in the Tunka valley, Russia. The new design of scintillation detector with wavelength shifting bars and PMTs is developed. The first prototype of the counter was installed and tested using infrastructure of the Tunka-GRANDE installation in 2017. The mass production of counters has begun in 2018 at the Novosibirsk State University.

The Tunka-Grande array is part of a single experimental complex, which also includes the Tunka-133 and TAIGA-HiScORE (High Sensitivity COsmic Rays and gamma Explorer) wide-angle Cherenkov arrays, TAIGA-IACT array (Imaging Atmospheric Cherenkov Telescope) and TAGA-MUON scintillation array. This complex is located in the Tunka Valley (Buryatia Republic, Russia), 50 km from Lake Baikal. It is designed to study the energy spectrum and the mass composition of charged cosmic rays in the energy range 100 TeV - 1000 PeV, to search for diffuse gamma rays above 100 TeV and to study local sources of gamma rays with energies above 30 TeV. This report outlines 3 key points. The first is the description of the Tunka-Grande scintillation array. The second one presents the computer simulation strategy of the Tunka Grande array based on the Geant4 software. The third one is devoted to the prospects for future research in the field of cosmic ray physics and gamma-ray astronomy using simulation results.

The Middle Jurassic A6 Anomaly is located 30 km southeast of Eskay Creek, north-central British Columbia and consists of thick, altered felsic igneous rocks overlain by a mafic volcano-sedimentary package. Lithogeochemistry on igneous rocks, X-ray diffraction on altered felsic units, and electron probe microanalysis and secondary ion mass spectrometry on illite and quartz were applied to explore the volcanogenic massive sulfide (VMS) potential, characterize alteration, and determine fluid conditions at the A6 Anomaly. Lithogeochemistry revealed calc-alkaline rhyodacite to trachyte of predominantly FII type, tholeiitic basalts with Nb/Yb &lt, 1.6 (i.e., Group A), and transitional to calc-alkaline basalts and andesites with Nb/Yb &gt, 2.2 (i.e., Group B). The felsic units showed weakly to moderately phyllic alteration (quartz–illite with minor orthoclase and trace chlorite–pyrite–calcite–barite–rutile). Illite ranged in composition from illite/smectite (K = 0.5–0.69 apfu) to almost endmember illite (K = 0.69–0.8 apfu), and formed from feldspar destruction by mildly acidic, relatively low temperature, oxidized hydrothermal fluids. The average δ18O composition was 10.7 ± 3.0‰ and 13.4 ± 1.3‰ relative to Vienna Standard Mean Ocean Water for illite and quartz, respectively. Geothermometry involving illite composition and oxygen isotope composition on illite and quartz yielded average fluid temperatures of predominantly 200–250 °C. Lithogeochemical results showed that the A6 Anomaly occurred in a late-Early to Middle Jurassic evolving back-arc basin, further east then previously recognized and in which transitional to calc-alkaline units formed by crustal assimilation to enriched Mid-Ocean Ridge Basalt (EMORB) (i.e., felsic units, Group B), followed by thinning of the crust resulting in tholeiitic normalized MORB basalts (i.e., Group A) with a minor crustal component. The alteration assemblage is representative of distal footwall alteration, and metal transport in this zone was limited despite favorable temperature, pH, and redox state, indicating a metal depleted source (i.e., felsic units).

The Tunka-Grande and TAIGA-Muon arrays are the part of a single experimental complex, which also includes the Tunka-133 and TAIGA-HiSCORE (High Sensitivity COsmic Rays and gamma Explorer) wide-angle Cherenkov arrays, TAIGA-IACT array (Imaging Atmospheric Cherenkov Telescope) and Tunka-Rex radio antennas array (Tunka Radio Extension). This complex is located in the Tunka Valley (Buryatia Republic, Russia), 50 km from Lake Baikal. It is aimed at investigating the energy spectrum and mass composition of charged cosmic rays in the energy range 100 TeV - 1000 PeV, searching for diffuse gamma rays above 100 TeV and studying local sources of gamma rays with energies above 30 TeV. This report outlines 3 key points. The first is a description of the Tunka-Grande and TAIGA-Muon scintillation arrays. The second part presents preliminary results of the search for diffuse gamma rays with energies above 50 PeV according to the Tunka-Grande data. The third part is devoted to the prospects of the search for diffuse gamma rays with energies above 100 TeV using the TAIGA-Muon array.

The Ming deposit in the northwestern Canadian Appalachians is a metamorphosed, bimodal-mafic, precious-metal (Au, Ag)-bearing and Cu-rich volcanogenic massive sulfide (VMS) deposit consisting of several, spatially proximal lenses in a sericite- to chlorite-altered rhyodacitic footwall. The various lenses (1807 Zone, 1806 Zone, Ming South Up Plunge, Ming South Down Plunge, and the Lower Footwall Zone) have variations in Cu, Au, Ag, and Zn grades that reflect varying physico-chemical conditions of ore formation. This study describes the complex ore mineralogy of the orebodies and constrains the genesis of the deposit using field methods, mineralogy, whole rock sulfide geochemistry, and micro-analytical methods. The orebodies are predominantly pyrite, chalcopyrite, with lesser sphalerite, pyrrhotite, and trace galena and arsenopyrite, with the exception of the Lower Footwall Zone, which consists of a high temperature (> 320 °C) chalcopyrite–pyrrhotite–pyrite ± cubanite assemblage. The other orebodies (1806, 1807, Ming South Up Plunge and Down Plunge) contain trace amounts of tellurides (hessite, altaite, tsumoite, unnamed bismuthtelluride), sulfosalts (Ag-poor and Ag-rich tennantite–tetrahedrite, meneghinite, AgSb phases, stannite), and precious metal phases (electrum, AgHg ± Au alloys). The 1807 Zone is enriched in Te, Bi, and Se, whereas the 1806 Zone is telluride-free and contains As, Sb, Hg, Au, and Ag. Mineral chemistry of sphalerite shows strong variations in Fe content (1.12–11.04 wt.%). Intermediate Fe (4.33–6.33 wt.% Fe) and Fe-rich (7.327–11.04 wt.% Fe) sphalerite are common in all orebodies, whereas Fe-poor sphalerite (1.12–3.57 wt.% Fe) occurs exclusively in the 1807 and 1806 zones. Tennantite-tetrahedrite is typically Ag-poor (0.25–2.19 wt.%) in the 1807 Zone, but is significantly enriched in Ag (up to 29.3 wt.%) in the 1806 Zone. Galena in the 1807 Zone and Ming South orebodies is commonly myrmekitically intergrown with tellurides and has high concentrations of Te, Bi, Se, and Ag. In contrast, galena in the 1806 Zone is less enriched in Te, Bi, and Se, but high in Ag. Variations in mineralogy, epithermal elements (As, Bi, Hg, Sb, Se, Sn, Te) and precious metal (Ag, Au) content, and mineral chemistry between the different orebodies indicate that they were formed from predominantly reduced, acidic hydrothermal fluids with varying ƒTe2/ƒS2, ƒSe2/ƒS2, and mBi/mSb ratios as temperatures steadily decreased from > 300 °C to

Pyrolysis oil produced from forestry residues is used as a low-grade fuel in applications such as heating oil. However, the high water and acid content can lead to fuel instability, phase separation, poor lubrication, and corrosion. In this work, pervaporation has been studied as a process to simultaneously upgrade a pyrolysis oil produced from Canadian softwood bark to meet a boiler fuel standard and extract value-added chemicals. Commercial polyacrylonitrile-supported polyvinyl alcohol membranes from DeltaMem AG were used at temperatures of 60 and 80 °C to separate water and volatile organic components, including methanol, acetic acid, and acetol. A design of experiment study was used to define the range of operating conditions. A temperature of 80 °C and a low feed flow rate of 0.1 mL min−1 resulted in the highest quality oil. The upgraded pyrolysis oil (pervaporation retentate) showed an increased heating value from incomplete combustion to 16.07 MJ kg−1 and the water content was lowered from 70.2 wt% in the feedstock to 21.4 wt%, demonstrating the potential for this process on a larger scale.

The influence of the amount of Pt deposited onto Rh and Ru nanoparticles on the oxidation of methanol and ethanol has been compared in H2SO4(aq) at ambient temperature and in a proton exchange membrane (PEM) cell at 80 °C. In H2SO4(aq), Rh@Pt and Ru@Pt show similar enhancements in activities over Pt for both methanol and ethanol oxidation. However, differences in the optimum Pt coverage indicate that compression of the Pt lattice by Rh plays a dominate role, while ligand effects are more important for Ru@Pt. In the PEM cell, the Ru core enhanced activities significantly for both methanol and ethanol, while activities were suppressed by the Rh core. This may arise from dominance of ligand and/or bifunctional effects for the Ru@Pt catalyst at 80 °C. Data from the PEM cell showed that the stoichiometry for ethanol oxidation at Ru@Pt was higher than for Rh@Pt, indicating a higher selectivity for the complete oxidation to CO2.

Mixed Ru–Sn oxides have been deposited onto a high surface area carbon support by thermal decomposition of Ru and Sn acetylacetonate (acac) complexes. Adsorption of preformed Pt nanoparticles produced catalysts with enhanced low potential activity for the oxidation of ethanol in aqueous sulfuric acid at ambient temperature and in a proton exchange membrane (PEM) cell at 80 °C. Varying the oxide composition between Ru0.38Sn0.62O2 and Ru0.67Sn0.33O2 did not influence the catalyst’s activity greatly but did increase stability in the sulfuric acid solution. Higher stability was observed in the PEM cell, where a Pt/Ru0.55Sn0.45O2/C anode provided much higher currents than a commercial Pt/C catalyst for ethanol oxidation at low potentials. Anodes for direct ethanol fuel cells can be fabricated by coating a carbon fibre paper backing layer consecutively with carbon black, Ru(acac)3 + Sn(acac)2, and Pt nanoparticles, with appropriate thermal processing.

Common fragile sites (cFSs) represent parts of the normal chromosome structure susceptible to breakage under replication stress. Although only a small number of cFSs have been molecularly characterized, genomic damage of cFS genes appears to be critical for the development of various human diseases. In this study, we fine mapped the location of FRA14B and showed that the fragile region spans 765 kb at 14q23.3, containing the large gephyrin (GPHN) gene. The FRA14B sequence is enriched in perfect A/T>24 stretches and R-loop forming sequences (RLFS), and harbors a large palindromic motif in the core region. FRA14B instability is not only limited to lymphocytes, but also occurs in neuroblastoma and breast epithelial cells. Using array comparative genomic hybridization (CGH), we examined copy number alteration patterns within FRA14B in a panel of 180 cancer cell lines and primary tumors. Our CGH data and a survey of 1046 Cancer Cell Line Encyclopedia profiles demonstrate that focal deletions cluster within FRA14B and disrupt the genomic integrity of GPHN in approximately 5% of cancer cells. Moreover, germline CNVs (copy number variants) profiles provided by the Database of Genomic Variants and available literature suggest that germline CNVs and rare pathogenic deletions associated with neurodevelopmental disorders cluster within the core fragile region of GPHN. Overall, our data provide insight into the molecular structure of FRA14B, and identify GPHN, as a large cFS gene in the human genome, whose disruption appears to trigger various neurodevelopmental diseases.

The physics motivations and advantages of the new TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) detector are presented. TAIGA aims at gamma-ray astronomy at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. For the energy range 30 – 200 TeV the sensitivity of 10 km2 area TAIGA array for the detection of local sources is expected to be 5 × 10-14 erg cm-2 sec-1 for 300 h of observations. Reconstruction of the given EAS energy, incoming direction and its core position, based on the timing TAIGA-HiSCORE data, allows one to increase a distance between the IACTs up to 600-1000 m. The low investments together with the high sensitivity for energies ≥ 30-50 TeV make this pioneering technique very attractive for exploring the galactic PeVatrons and cosmic rays. At present the TAIGA first stage has been constructed in Tunka valley, 50 km West from the Lake Baikal. The first experimental results of the TAIGA first stage are presented.

In TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) detector we are commissioning the first Imaging Atmospheric Cherenkov Telescope (IACT). The telescope drive system comprises a motor controller and two stepper motors for axis control. For the pointing calibration of the telescope a CCD-camera is installed on the reflector dish of the telescope. The position of the CCD-camera allows us capturing both the Cherenkov camera and the observed source. In this report we describe the telescope positioning and the drive system software as well as the control of the CCD-camera data acquisition, archiving and processing system.

We report the first ground-based observation of the CATS-LIDAR onboard the ISS by the TAIGA-HiSCORE gamma-ray facility, and the MASTER-Tunka Robotic telescope. HiSCORE detects unscattered laser light directly from the ISS, at up to km-scale distance from the laser beam spot on ground. The ISS-LIDAR turns out to be a unique calibration tool, in particular to verify the absolute astronomical pointing of HiSCORE. We detected the LIDAR for 11 ISS-passages; among these were observations of forward scattering of the laser beam in dense clouds, which might carry information complementary to the LIDAR technique. We expect other air Cherenkov installations like IACTs to benefit from this light source.

The very to ultra high energy gamma-ray regime up to several 100 TeV is the key to spectrally resolve the cutoff regime of the long-sought Pevatrons, the Galactic cosmic-ray PeV accelerators. One component of the TAIGA hybrid detector is the TAIGA-HiSCORE shower-front sampling timing array, which currently consists of 28 wide angle (0.6\,sr) air Cherenkov timing stations distributed on an area of 0.25 km$^{2}$, and which will be doubled in area by fall 2017. We report on the status and first results of the HiSCORE timing array after the first 2 operation seasons, including calibration studies on timing and pointing, cross calibration with data from the first TAIGA-IACT, observations with the timing array of a LIDAR operating on the ISS, a measurement of the Cosmic Ray spectrum, and a systematic search for high energy gamma-rays from Galactic sources such as the Crab.

The Ming deposit, Baie Verte, Newfoundland, Canada, is an Early Ordovician bimodal-mafic, Cu-Au-(Zn-Ag) volcanogenic massive sulfide (VMS) deposit. The deposit consists of a number of ore lenses that are stacked in the uppermost part of the Rambler rhyolite. One of the uppermost lenses, the 1806 zone, is enriched in Au and Ag. The deposit has been affected by Silurian-Devonian greenschist to amphibolite grade metamorphism and polyphase deformation and this has led to debates as to whether the Au-Ag enrichment in the deposit is syngenetic or a product of a later metamorphic and structural overprint. The 1806 zone consists predominantly of discordant sulfide stringer, stratabound semimassive to massive sulfides and a weakly mineralized silicified cap zone. The ore is largely hosted within the footwall Rambler rhyolite that is strongly altered to quartz-sericite ± green mica with sporadic chlorite-biotite. Base and precious metal zoning is developed from the down-plunge portion (Cu-Au) to the up-plunge portion (Cu-Zn-Au-Ag-Pb) of the 1806 zone. The ore mineralogy and mineral chemistry are complex and are interpreted to be of an intermediate sulfidation type. Pyrite and chalcopyrite are the dominant sulfide species with minor to accessory sphalerite, galena, pyrrhotite, and arsenopyrite. Sulfosalts including Ag-bearing tennantite-tetrahedrite, stannite, boulangerite, and loellingite, and precious metal-rich phases are common throughout the deposit. Precious metals occur as (1) mercurian electrum (7.93–20.57 wt % Hg) and (2) various Ag phases (miargyrite, pyrargyrite, mercurian stephanite, unnamed AgCuFeS phase, Ag-Hg ± Au alloys) that are more abundant in the up-plunge portion of the 1806 zone. Tellurides and bismuthides are present in trace amounts. Oxides (cassiterite and magnetite) are present exclusively in the down-plunge portion of the 1806 zone. The deposit geometry, metals distribution, complex ore assemblages, abundant sulfosalts, and the significant concentration of the epithermal suite of elements (e.g., Au, Ag, As, Hg, Sb, Bi) in the ore strongly contrast with those of orogenic Au deposits and support a syngenetic or synvolcanic origin for precious metals in the Ming VMS deposit, including a possible magmatic input into the 1806 zone ore-forming system. Evidence for a late, syndeformation precious metal emplacement via orogenic overprinting is lacking at the 1806 zone and all data point to a syngenetic origin for precious metal enrichment, indicating that Ordovician Appalachian VMS deposits are favorable targets for Au. Nevertheless, Silurian-Devonian metamorphism and deformation have resulted in textural recrystallization and local remobilization of precious metals and the main fabrics largely control the current geometry of the host succession and of the Ming orebody.

Pyrolysis oil from softwood forestry residues (sawdust and bark) often contains too much water to be a useful fuel. Excess water can be removed by distillation or pervaporation to meet the ASTM burner fuel standard, while producing methanol rich aqueous distillates/permeates. This work focuses on electrolysis of the aqueous byproduct stream to produce hydrogen. Short-path vacuum distillation produced the best fuel, but acetic acid, hydroxyacetone, acrolein, and other impurities strongly suppressed the electrolysis of the methanol. However, fractional distillation produced a distillate that could be electrolyzed at 14 mA cm−2 at 0.4 V at a PtRu catalyst, and 220 mA cm−2 at 0.9 V at a Pt catalyst. Pervaporation also produced a standard fuel, while electrolysis of permeates produced current densities as high as 44 mA cm−2 at 0.5 V and 240 mA cm−2 at 0.9 V. There is scope for substantial improvements by decreasing the effect of impurities.

In TAIGA Observatory (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) we are commissioning the first Imaging Atmospheric Cherenkov Telescope (IACT). The telescope has an alt-azimuth mount and 17-bit shaft encoder for each axis, stepper motors are used for axis control. For the pointing calibration of the telescope a CCD-camera is installed on the dish of the telescope and its position allows to capture simultaneously both the Cherenkov camera with LEDs and the sky with observed source. Since October 2017, the telescope has been operating in tracking mode. In this work the TAIGAIACT telescope pointing calibration approach and first results of the tracking operations are described.

Specific patterns of genomic aberrations have been associated with different types of malignancies. In colorectal cancer, losses of chromosome arm 8p and gains of chromosome arm 8q are among the most common chromosomal rearrangements, suggesting that the centromeric portion of chromosome 8 is particularly sensitive to breakage. Genomic alterations frequently occur in the early stages of tumorigenesis at specific genomic regions known as common fragile sites (cFSs). CFSs represent parts of the normal chromosome structure that are prone to breakage under replication stress. In this study, we identified the genomic location of FRA8I, spanning 530 kb at 8q11.21 and assessed the composition of the fragile DNA sequence. FRA8I encompasses KIAA0146, a large protein-coding gene with yet unknown function, as well as CEBPD and part of PRKDC, two genes encoding proteins involved in tumorigenesis in a variety of cancers. We show that FRA8I is unstable in lymphocytes and epithelial cells, displaying similar expression rates. We examined copy number alteration patterns within FRA8I in a panel of 25 colorectal cancer cell lines and surveyed publically available profiles of 56 additional colorectal cancer cell lines. Combining these data shows that focal recombination events disrupt the genomic integrity of KIAA0146 and neighboring cFS genes in 12.3% of colorectal cancer cell lines. Moreover, data analysis revealed evidence that KIAA0146 is a translocation partner of the immunoglobulin heavy chain gene in recurrent t(8;14)(q11;q32) translocations in a subset of patients with B-cell precursor acute lymphoblastic leukemia. Our data molecularly describe a region of enhanced chromosomal instability in the human genome and point to a role of the KIAA0146 gene in tumorigenesis.

The TP53 tumor suppressor pathway is abrogated by TP53 mutations in the majority of human cancers. Increased levels of wild-type TP53 in aggressive neuroblastomas appear paradox but are tolerated by tumor cells due to co-activation of the TP53 ubiquitin ligase, MDM2. The role of the MDM2 antagonist, p14(ARF), in controlling the TP53-MDM2 balance in neuroblastoma is unresolved. In the present study, we show that conditional p14(ARF) expression substantially suppresses viability, clonogenicity and anchorage-independent growth in p14(ARF)-deficient or MYCN-amplified neuroblastoma cell lines. Furthermore, ectopic 14(ARF) expression induced accumulation of cells in the G1 phase and apoptosis, which was paralleled by accumulation of TP53 and its targets. Comparative genomic hybridization analysis of 193 primary neuroblastomas detected one homozygous deletion of CDKN2A (encoding both p14(ARF) and p16(INK4A)) and heterozygous loss of CDKN2A in 22% of tumors. Co-expression analysis of p14(ARF) and its transactivator, E2F1, in a set of 68 primary tumors revealed only a weak correlation, suggesting that further regulatory mechanisms govern p14(ARF) expression in neuroblastomas. Intriguingly, analyses utilizing chromatin immunoprecipitation revealed different histone mark-defined epigenetic activity states of p14(ARF) in neuroblastoma cell lines that correlated with endogenous p14(ARF) expression but not with episomal p14(ARF) promoter reporter activity, indicating that the native chromatin context serves to epigenetically repress p14(ARF) in neuroblastoma cells. Collectively, the data pinpoint p14(ARF) as a critical factor for efficient TP53 response in neuroblastoma cells and assign p14(ARF) as a neuroblastoma suppressor candidate that is impaired by genomic loss and epigenetic repression.

Common fragile sites (cFSs) are non-random chromosomal regions that are prone to breakage under conditions of replication stress. DNA damage and chromosomal alterations at cFSs appear to be critical events in the development of various human diseases, especially carcinogenesis. Despite the growing interest in understanding the nature of cFS instability, only a few cFSs have been molecularly characterised. In this study, we fine-mapped the location of FRA2H using six-colour fluorescence in situ hybridisation and showed that it is one of the most active cFSs in the human genome. FRA2H encompasses approximately 530 kb of a gene-poor region containing a novel large intergenic non-coding RNA gene (AC097500.2). Using custom-designed array comparative genomic hybridisation, we detected gross and submicroscopic chromosomal rearrangements involving FRA2H in a panel of 54 neuroblastoma, colon and breast cancer cell lines. The genomic alterations frequently involved different classes of long terminal repeats and long interspersed nuclear elements. An analysis of breakpoint junction sequence motifs predominantly revealed signatures of microhomology-mediated non-homologous recombination events. Our data provide insight into the molecular structure of cFSs and sequence motifs affected by their activation in cancer. Identifying cFS sequences will accelerate the search for DNA biomarkers and targets for individualised therapies.

Common fragile sites (cFS) represent chromosomal regions that are prone to breakage after partial inhibition of DNA synthesis. Activation of cFS is associated with various forms of DNA instability in cancer cells, and is thought to be an initiating event in the generation of DNA damage in early-stage tumorigenesis. Only a few cFS have been fully characterized despite the growing interest in cFS instability in cancer genomes. In this study, six-color fluorescence in situ hybridization revealed that FRA2C consists of two cFS spanning 747 kb FRA2Ctel and 746 kb FRA2Ccen at 2p24.3 and 2p24.2, respectively. Both cFS are separated by a 2.8 Mb non-fragile region containing MYCN. Fine-tiling array comparative genomic hybridization of MYCN amplicons from neuroblastoma (NB) cell lines and primary tumors revealed that 56.5% of the amplicons cluster in FRA2C. MYCN amplicons are either organized as double minutes or as homogeneously stained regions in addition to the single copy of MYCN retained at 2p24. We suggest that MYCN amplicons arise from extra replication rounds of unbroken DNA secondary structures that accumulate at FRA2C. This hypothesis implicates cFS in high-level gene amplification in cancer cells. Complex genomic rearrangements, including deletions, duplications and translocations, which originate from double-strand breaks, were detected at FRA2C in different cancers. These data propose a dual role for cFS in the generation of gross chromosomal rearrangements either after DNA breakage or by inducing extra replication rounds, and provide new insights into the highly recombinogenic nature of cFS in the human cancer genome.

The problem of chemical composition below the knee in the cosmic-ray energy spectrum has not yet been solved due to low statistics collected from direct experiments. In the HiSCORE experiment the lateral distribution functions (LDF) of Cherenkov light of EASs with energy greater than hundreds of TeV can be measured in detail for millions of individual events. A full steepness of LDF is sensitive to the depth of shower maximum and as a result to primary particle type. In this paper, we developed a parametric method of separation between heavy and light groups of nuclei using the ’knee-like’ approximation of LDF and taking into account measurement uncertainty.

In this paper, the authors present the concept of a system for Distance Object Learning and Evaluation (DOLE), which can be used during the teaching-learning process as a virtual learning environment. The term Distance Object Learning is used here for learning over a computer network or the Internet about real world entities that are distinguishable from others. The DOLE system concept uses standards for Learning Object Metadata (LOM) at different levels of abstraction. The objective of the resulting system is not only the correct and retrievable description of the course material covered by the LOM but also the further use of parts of the LOM data set for the generation of learning materials and students' learning development assessment, which can be represented by quizzes and tests. The Distance Object Learning and Evaluation system concept outlined in this paper is based in part on an earlier version of an E-learning Assessment System for Young learners (EASY). DOLE extends the concept of EASY by a learning component and by posing system generated questions with the help of a forward-chaining inference engine to find out about a specific item (object) of the domain of instruction. As the questioning process is bidirectional ("open" questions can be asked by the system as well as by the learner), DOLE is more targeted at advanced and adult learners than at young learners. The ultimate goal is to use the DOLE system concept as a part of a virtual college or university.

The bibliographic review has a long tradition in“Geostandards Newsletter” and Geostandards andGeoanalytical Research(GGR). Successive reviewshave complied and classified articles from geochemi-cal, cosmochemical, environmental, analytical andgeological journals in which data for reference mate-rials (RMs) of geological and environmental interestwere published. As discussed in the bibliographicreview for 2006 (Jochum 2007) and in Jochum andNohl (2008), the number of geochemical publicationshas increased significantly during recent years. Thistrend continued in 2007. Figure 1 shows the numberof publications containing data for RMs, which havebeen published in the bibliographic reviews for theyears 2001-2007. The number increased slowly from220 to 340 in the five year period from 2001 to2005, then steeply to 540 in 2006 and 710 in 2007(data for 2006 in this figure were corrected becauseeighty-four papers were not considered in Jochum(2007)). The same trend can be observed for someselected RMs (Figure 1), such as the three well-knownUSGS RMs BCR-1, BCR-2 (the replacement for BCR-1)and BCR-2G (a glass made from BCR-2 and mainlyused for microanalytical purposes). Reasons for thisincrease are that the importance of RMs in analyticalwork has been recognised by geochemists (Goldsteinet al.2003, Jochum and Nohl 2008) and that geoa-nalytical laboratories are being confronted with newfields and applications, such as environmental andbiogeochemical research, “non-traditional stable iso-tope” systems and microanalysis.This review contains 710 papers from the publica-tion year 2007. Literature research was performed on

This review surveys the literature on reference materials for geological and environmental research for the two year period 2006–2007. In this time ca. 1200 publications appeared containing analytical data on reference materials, indicating that their importance for analytical work has been recognised by geochemists and environmental scientists. Although many reference materials exist, there remains a pressing need for further samples, especially for certified rock reference materials, homogeneous reference glasses, mineral reference materials and so-called delta-zero materials for normalisation purposes of stable isotopes. This review focuses on six topics: rock reference materials, reference materials for platinum-group elements, reference glasses, mineral reference materials, environmental reference materials (seawater, soil) and isotopic reference materials (radiogenic, stable isotopes). In addition, a short description is given of the GeoReM database for reference materials of geological and environmental interest, which contains analytical data from the publications discussed in this review.

In the current study, an experimental study on two-phase flow at different orientations is carried out at the Fluids Laboratory, Memorial University of Newfoundland (MUN). Three different orientations are used. They are horizontal, vertical and slanted orientation respectively. The experimental unit consists of pipes that are three inches (DN 80) in diameter and are capable of producing many various regimes of gasliquid flows. The experimental unit has sensors to measure the pressure, temperature and volume flow at numerous locations. Experiments are conducted for two-phase flow (bubble and slug flow). The new experimental data can provide valuable insights on the viscous effects with many flow regimes, phase compositions and direction of flow. The results of this research provide valuable new experimental data on two-phase flow characteristics for many flow regimes that can improve the safety and efficiency of wellstream flows.Copyright © 2015 by ASME