U-Pb Geochronology of the Miocene Peach Spring Tuff Supereruption And Precursor Cook Canyon Tuff, Western Arizona, USA

The 18.8 Ma Peach Spring Tuff, Arizona, is a \u3e600 km3 ignimbrite formed from the Miocene supereruption of Silver Creek caldera, Black Mountains, Arizona, and is an important Miocene stratigraphic bed in the southwestern United States. Peach Spring Tuff overlies the undated and less-voluminous Cook Canyon Tuff. Ion-microprobe and high-precision thermal ionization U-Pb dating of chemically abraded zircon crystals from Peach Spring Tuff and Cook Canyon Tuff reveal the crystallization history of both magma systems leading to eruption. A spread of U-Pb dates from ca. 18.1 to 22.0 Ma for Peach Spring Tuff relative to its 40Ar/39Ar age indicates variable Pb loss, with potential additional uncertainty due to complexities associated with 40Ar/39Ar dating. The youngest U-Pb crystallization date for Cook Canyon Tuff zircon crystals constrains the maximum eruption age to ca. 18.9 Ma, and indicates that eruption of the Cook Canyon Tuff preceded the Peach Spring Tuff eruption by no more than 2-3 x 105 years. The complex U-Pb zircon age spectra for both units indicate several 105 years of pre-eruptive magma residence, likely in a crystal mush state. When combined, the ages and trace elements for Peach Spring Tuff and Cook Canyon Tuff zircon crystals suggest that these two silicic magmas were derived from discrete but temporally and spatially overlapping magma systems

Investigating the Toxicity and Accumulation of 2,4-Dichlorophenoxyacetic Acid (2,4-D) and Glyphosate in Eisenia fetida

Glyphosate, the main ingredient in Roundup®, is the most widely used herbicide in the world. It is also used in combination with another effective herbicide, 2,4-D, in the formulation called Enlist Duo®. The EPA approved the use of Enlist Duo® on certain crops including those genetically modified to be resistant to both herbicides. The predicted significant increase in the use of these herbicides raised concerns from the general public because both compounds have been classified as possibly or probably carcinogenic. Since herbicides are applied directly to vegetation, the safety of organisms that come in contact with the herbicides is at risk. In this toxicity study, the responses of earthworms exposed to various concentrations of 2,4-D, glyphosate, or both were investigated. Results of direct contact studies show severe effects of 2,4-D on worms, including death. Despite seeing ill effects in direct contact trials, we saw no significant difference in the mortality rates, reproductive health, and weight of the earthworms treated via ingestion of contaminated soil or vegetation. As earthworms constitute a food source for other organisms, bioaccumulation is possible. An HPLC method to detect herbicide uptake in earthworm tissues was also developed. These methods were suitable for analyzing worms obtained from soil and plants treated with 2,4-D, glyphosate, or both. HPLC analysis showed uptake of both 2,4-D and glyphosate but no evidence indicating that the presence of 2,4-D changed the uptake of glyphosate

Multiple novel non-canonically transcribed sub-genomic mRNAs produced by avian coronavirus infectious bronchitis virus

Funding: This work was supported by Biotechnology and Biological Sciences Research Council (BBSRC) grants BB/L003988/1 and 1645891, and strategic funding to The Pirbright Institute, BBS/E/I/00007035, BBS/E/I/00007034, BBS/E/I/00007037 and BBS/E/I/00007039.Coronavirus sub-genomic mRNA (sgmRNA) synthesis occurs via a process of discontinuous transcription involving complementary transcription regulatory sequences (TRSs), one (TRS-L) encompassing the leader sequence of the 5' untranslated region (UTR), and the other upstream of each structural and accessory gene (TRS-B). Several coronaviruses have an ORF located between the N gene and the 3'-UTR, an area previously thought to be non-coding in the Gammacoronavirus infectious bronchitis virus (IBV) due to a lack of a canonical TRS-B. Here, we identify a non-canonical TRS-B allowing for a novel sgmRNA relating to this ORF to be produced in several strains of IBV: Beaudette, CR88, H120, D1466, Italy-02 and QX. Interestingly, the potential protein produced by this ORF is prematurely truncated in the Beaudette strain. A single nucleotide deletion was made in the Beaudette strain allowing for the generation of a recombinant IBV (rIBV) that had the potential to express a full-length protein. Assessment of this rIBV in vitro demonstrated that restoration of the full-length potential protein had no effect on viral replication. Further assessment of the Beaudette-derived RNA identified a second non-canonically transcribed sgmRNA located within gene 2. Deep sequencing analysis of allantoic fluid from Beaudette-infected embryonated eggs confirmed the presence of both the newly identified non-canonically transcribed sgmRNAs and highlighted the potential for further yet unidentified sgmRNAs. This HiSeq data, alongside the confirmation of non-canonically transcribed sgmRNAs, indicates the potential of the coronavirus genome to encode a larger repertoire of genes than has currently been identified.Publisher PDFPeer reviewe

Verification of the Hydrogeological Map of Poland (HMP), 1:50 000, exemplified by the Gdańsk region

Gdański system wodonośny wyróżnia się złożonym systemem hydrostrukturalnym, obejmującym trzy piętra wodonośne: czwartorzędowe, paleogeńsko-neogeńskie i kredowe. Pełną charakterystykę czwartorzędowego piętra wodonośnego przedstawiono na poszczególnych arkuszach Mapy Hydrogeologicznej Polski w skali 1:50 000. W artykule zaprezentowano rozkład najważniejszych parametrów hydrogeologicznych palegeńsko-neogeńskiego i kredowego piętra wodonośnego w centralnej części gdańskiego systemu wodonośnego. Specjalnie opracowane mapy ilustrują zasięg, hydrodynamikę i wydajność potencjalną studzien ujmujących mioceński, oligoceński i kredowy poziom wodonośny. Przedstawione dane mogą być pomocne przy weryfikacji zasobów dyspozycyjnych wód podziemnych gdańskiego systemu wodonośnego.The Gdańsk hydrogeological system comprises a multiaquifer hydrostructural system that includes Quaternary, Neogene-Paleogene and Cretaceous water-bearing strata periods. The characteristics of the Quaternary aquifer is presented in the Hydrogeological Map of Poland (HMP), 1:50 000. This article presents distribution of the main hydrogeological parameters in the Neogene-Paleogene and Cretaceous multiaquifer formations in the central part of the Gdańsk hydrogeological system. The special maps illustrate the dynamics, potential discharge of wells and extents of the Miocene, Oligocene and Cretaceous aquifers. Hydrogeological maps of the Neogene-Paleogene and Cretaceous multiaquifer formations will be useful to asses groundwater resources of this hydrogeological system

Identification of groundwater circulation system during assessment renewable resources for example of the Reda and Zagórska Struga catchment

The study area of about 1,000 km2 include northern part of Cashubian Lake District. The objective of the task was to recognition of groundwater circulation system and renawable resources. Detailed system of groundwater circulation was exemplified for Reda drainage basin. This work presents results of numerical models of groundwater in Reda and Zagórska Struga catchment and results of hydrological investigation. Results of numerical model estimated recharge and recharge of groundwater treatment for eliminated groundwater layers reduced in numerical models to 8 layers and groundwater balance regions. This evaluation, made according to three-dimensional filtration model on the assumption that a steady groundwater flow. The results of model simulation show that recharge area occur Kashubian Lake District and discharge area occur Reda ice marginal valley. It means that the total disposable groundwater resources for the specified area equals 520,605 m324h