scholarly journals Clinopyroxene Crystals in Basic Lavas of the Marsili Volcano Chronicle Early Magmatic Stages in a Back-Arc Transcrustal Mush System

Geosciences ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 159
Author(s):  
Teresa Trua ◽  
Michael P. Marani

Constraining the pre-eruptive processes that modulate the chemical evolution of erupted magmas is a challenge. An opportunity to investigate this issue is offered by the interrogation of the crystals carried in lavas. Here, we employ clinopyroxene crystals from back-arc lavas in order to identify the processes driving basalt to andesite magma evolution within a transcrustal plumbing system. The assembled clinopyroxene archive reveals that mantle melts injected at the crust-mantle transition cool and crystalize, generating a clinopyroxene-dominated mush capped by a melt-rich domain. Magma extracted from this deep storage zone fed the eruption of basalt to basaltic andesite lavas. In addition, chemically evolved melts rapidly rising from this zone briefly stalled at shallow crustal levels, sourcing crystal-poor andesite lavas. Over time, hot ascending primitive magmas intercepted and mixed with shallower cooling magma bodies forming hybrid basic lavas. The blended clinopyroxene cargoes of these lavas provide evidence for the hybridization, which is undetectable from a whole-rock chemical perspective, as mixing involved chemically similar basic magmas. The heterogeneity we found within the clinopyroxene archive is unusual since it provides, for the first time, a complete set of mush-related scenarios by which mantle melts evolve from basalt to andesite compositions. Neither the whole-rock chemistry alone nor the record of the mineral phases crystallizing subsequent to clinopyroxene can provide insights on such early magmatic processes. The obtained clinopyroxene archive can be used as a template for interpretation of the record preserved in the clinopyroxene cargoes of basalt to andesite lavas elsewhere, giving insights into the magma dynamics of the feeding plumbing system that are lost when using whole-rock chemistry.

2020 ◽  
Vol 94 ◽  
pp. 14-30 ◽  
Author(s):  
María M. Sampietro-Vattuone ◽  
Walter A. Báez ◽  
José L. Peña-Monné ◽  
Alfonso Sola

AbstractA comprehensive morphostratigraphic and chronological study of the complete set of Holocene tephras from Tafí and Santa María valleys (northwestern Argentina), including analyses of compositional characteristics, is presented. Five ash tephras are recognized: V0 (El Rincón), V1a (Carreras 1a ash), V1b (Carreras 1b ash), V2a (Carreras 2 ash), and V2b (El Paso 3 ash). Two of them (V1b and V2b) are described for the first time in the study area. The new 14C and accelerator mass spectrometry ages presented, along with the previously published information, allows for the establishment of a chronological framework. The V0 tephra was deposited in the Early Holocene (about 10,000 yr BP), V1a and V1b were deposited in the Middle Holocene (about 4200 and 3500 yr BP, respectively), and V2a and V2b were deposited in the Late Holocene (after about 800 yr BP). The mineralogical, textural, and geochemical characterizations of the five tephras suggest that their tephra provenance was mainly from the back-arc region. However, the determination of the exact source of each tephra requires more accurate high-resolution tephrochronological studies. At least five major eruptions affected the Tafí and Santa María valleys in the last 10,000 yr.


Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Carlos Alberto Ríos-Reyes ◽  
German Alfonso Reyes-Mendoza ◽  
José Antonio Henao-Martínez ◽  
Craig Williams ◽  
Alan Dyer

This study reports for the first time the geologic occurrence of natural zeolite A and associated minerals in mudstones from the Cretaceous Paja Formation in the urban area of the municipality of Vélez (Santander), Colombia. These rocks are mainly composed of quartz, muscovite, pyrophyllite, kaolinite and chlorite group minerals, framboidal and cubic pyrite, as well as marcasite, with minor feldspar, sulphates, and phosphates. Total organic carbon (TOC), total sulfur (TS), and millimeter fragments of algae are high, whereas few centimeters and not biodiverse small ammonite fossils, and other allochemical components are subordinated. Na–A zeolite and associated mineral phases as sodalite occur just beside the interparticle micropores (honeycomb from framboidal, cube molds, and amorphous cavities). It is facilitated by petrophysical properties alterations, due to processes of high diagenesis, temperatures up to 80–100 °C, with weathering contributions, which increase the porosity and permeability, as well as the transmissivity (fluid flow), allowing the geochemistry remobilization and/or recrystallization of pre-existing silica, muscovite, kaolinite minerals group, salts, carbonates, oxides and peroxides. X-ray diffraction analyses reveal the mineral composition of the mudstones and scanning electron micrographs show the typical cubic morphology of Na–A zeolite of approximately 0.45 mμ in particle size. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → sodalite → Na–A zeolite. A literature review shows that this is an unusual example of the occurrence of natural zeolites in sedimentary marine rocks recognized around the world.


Author(s):  
Alessandro Chiarini ◽  
Maurizio Quadrio

AbstractA direct numerical simulation (DNS) of the incompressible flow around a rectangular cylinder with chord-to-thickness ratio 5:1 (also known as the BARC benchmark) is presented. The work replicates the first DNS of this kind recently presented by Cimarelli et al. (J Wind Eng Ind Aerodyn 174:39–495, 2018), and intends to contribute to a solid numerical benchmark, albeit at a relatively low value of the Reynolds number. The study differentiates from previous work by using an in-house finite-differences solver instead of the finite-volumes toolbox OpenFOAM, and by employing finer spatial discretization and longer temporal average. The main features of the flow are described, and quantitative differences with the existing results are highlighted. The complete set of terms appearing in the budget equation for the components of the Reynolds stress tensor is provided for the first time. The different regions of the flow where production, redistribution and dissipation of each component take place are identified, and the anisotropic and inhomogeneous nature of the flow is discussed. Such information is valuable for the verification and fine-tuning of turbulence models in this complex separating and reattaching flow.


2020 ◽  
Vol 13 ◽  
pp. 175628482093518 ◽  
Author(s):  
Angélique Saint ◽  
Maxime Benchetrit ◽  
Sébastien Novellas ◽  
Denis Ouzan ◽  
Alexander Tuan Falk ◽  
...  

Introduction: Hepatocholangiocarcinoma (HCC-ICC) is a rare tumor presenting the histologic characteristics of both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). As there is no consensus on it management, the therapeutic strategy rests on the specific treatments for HCC or ICC. Programmed cell death 1 (PD-1) inhibitors showed encouraging results in the second line treatment of HCC after sorafenib but it efficacy in HCC-ICC has never been reported. Methods and results: We present the case of a 72-year-old male patient treated for metastatic HCC-ICC due to a viral hepatitis C cirrhosis in progression after two lines of treatment. Tumor was characterized by a PDL-1 status of 85%. Patient received pembrolizumab at doses of 200 mg every 21 days by intravenous infusion. After one injection he was presented an immediate clinical benefit, a partial response was observed after two months of treatment and a complete response two months later. This response was maintained over time along with toxicity-free tumor control after 18 months treatment. Conclusion: To our knowledge, we reported for the first time the efficacy of a PD1 inhibitor treatment in a patient presenting metastatic HCC-ICC due to viral cirrhosis and overexpressing PDL-1 after failure of two lines of treatment.


Microbiology ◽  
2004 ◽  
Vol 150 (7) ◽  
pp. 2257-2266 ◽  
Author(s):  
Helmuth Adelsberger ◽  
Christian Hertel ◽  
Erich Glawischnig ◽  
Vladimir V. Zverlov ◽  
Wolfgang H. Schwarz

Four extracellular enzymes of the thermophilic bacterium Clostridium stercorarium are involved in the depolymerization of de-esterified arabinoxylan: Xyn11A, Xyn10C, Bxl3B, and Arf51B. They were identified in a collection of eight clones producing enzymes hydrolysing xylan (xynA, xynB, xynC), β-xyloside (bxlA, bxlB, bglZ) and α-arabinofuranoside (arfA, arfB). The modular enzymes Xyn11A and Xyn10C represent the major xylanases in the culture supernatant of C. stercorarium. Both hydrolyse arabinoxylan in an endo-type mode, but differ in the pattern of the oligosaccharides produced. Of the glycosidases, Bxl3B degrades xylobiose and xylooligosaccharides to xylose, and Arf51B is able to release arabinose residues from de-esterified arabinoxylan and from the oligosaccharides generated. The other glycosidases either did not attack or only marginally attacked these oligosaccharides. Significantly more xylanase and xylosidase activity was produced during growth on xylose and xylan. This is believed to be the first time that, in a single thermophilic micro-organism, the complete set of enzymes (as well as the respective genes) to completely hydrolyse de-esterified arabinoxylan to its monomeric sugar constituents, xylose and arabinose, has been identified and the enzymes produced in vivo. The active enzyme system was reconstituted in vitro from recombinant enzymes.


2021 ◽  
pp. 213-222
Author(s):  
Dandan Wu ◽  
Xiaoxia Zhu ◽  
Lu Tan ◽  
Haiqin Zhang ◽  
Lina Sha ◽  
...  

The genera of the tribe Triticeae (family Poaceae), constituting many economically important plants with abundant genetic resources, carry genomes such as St, H, P, and Y. The genome symbol of <i>Roegneria</i> C. Koch (Triticeae) is StY. The St and Y genomes are crucial in Triticeae, and tetraploid StY species participate extensively in polyploid speciation. Characterization of St and Y nonhomologous chromosomes in StY-genome species could help understand variation in the chromosome structure and differentiation of StY-containing species. However, the high genetic affinity between St and Y genome and the deficiency of a complete set of StY nonhomologous probes limit the identification of St and Y genomes and variation of chromosome structures among <i>Roegneria</i> species. We aimed to identify St- and Y-enhanced repeat clusters and to study whether homoeologous chromosomes between St and Y genomes could be accurately identified due to high affinity. We employed comparative genome analyses to identify St- and Y-enhanced repeat clusters and generated a FISH-based karyotype of <i>R. grandis</i> (Keng), one of the taxonomically controversial StY species, for the first time. We explored 4 novel repeat clusters (StY_34, StY_107, StY_90, and StY_93), which could specifically identify individual St and Y nonhomologous chromosomes. The clusters StY_107 and StY_90 could identify St and Y addition/substitution chromosomes against common wheat genetic backgrounds. The chromosomes V_St, VII_St, I_Y, V_Y, and VII_Y displayed similar probe distribution patterns in the proximal region, indicating that the high affinity between St and Y genome might result from chromosome rearrangements or transposable element insertion among V_St/Y, VII_St/Y, and I_Y chromosomes during allopolyploidization. Our results can be used to employ FISH further to uncover the precise karyotype based on colinearity of Triticeae species by using the wheat karyotype as reference, to analyze diverse populations of the same species to understand the intraspecific structural changes, and to generate the karyotype of different StY-containing species to understand the interspecific chromosome variation.


Author(s):  
Л. Х. Пастушкова ◽  
Д. Н. Каширина ◽  
А. Г. Гончарова ◽  
Н. Б. Захарова ◽  
Е. С. Тийс ◽  
...  

Впервые описаны белки, достоверно увеличивающиеся и уменьшающиеся в моче с возрастом в интервале 20-60 лет. Охарактеризованы комбинации белков, связанных с изменением иммунных процессов, нарушением реологии крови, в том числе риском коагулопатии, противоопухолевых защитных механизмов, инсулинового сигнального пути, с изменением характеристик клеточного деления и качества новообразованной ткани. Таким образом, возрастная динамика основных процессов запускает каскад реакций, проявляющихся в замыкании «патологических биохимических кругов», которые формируют предпосылки к развитию заболеваний и, с течением времени, клинические проявления. For the first time proteins are described, reliably increasing and decreasing in urine with age in the range of 20 to 60 years. The combinations of proteins associated with changes in immune processes, violation of blood reology, including the risk of coagulopathy, anticancer defense mechanisms, insulin signaling pathway, changes in cell characteristics are characterized division and quality of the newly formed fabric. Thus, the age dynamics of the main processes triggers a cascade of reactions manifested in the closure of «pathological biochemical circles» that form the prerequisites for the development of diseases and, over time, clinical manifestations.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S27-S28 ◽  
Author(s):  
John DeVincenzo ◽  
Efi Gymnopoulou ◽  
Els De Paepe ◽  
Bryan Murray ◽  
Arangassery Rosemary Bastian ◽  
...  

Abstract Background Despite the high disease burden of RSV in older adults and children, there is currently no approved vaccine. Ad26.RSV.preF, an experimental RSV vaccine, has demonstrated immunogenicity and tolerability in first-in-human clinical studies. The aim of this study was to assess the potential of the Ad26.RSV.preF vaccine to protect against RSV infection and disease in an established RSV human challenge model, used for the first time to evaluate a vaccine. Methods We conducted a randomized, double-blind, placebo-controlled, human challenge study (NCT03334695). Healthy adults received 1 × 1011 vp Ad26.RSV.preF vaccine (active) or placebo (pbo) intramuscularly. After 28 days, volunteers were challenged intranasally with a low-passage clinical strain of RSV-A (0.8 mL of Memphis 37b) and then quarantined for 12 days. Nasal washes were collected twice daily throughout quarantine, starting 2 days post-challenge (viral load [VL] by qRT-PCR and quantitative cultures). Disease severity was recorded thrice daily using symptom diary cards. Results Fifty-three volunteers (active, n = 27; pbo, n = 26) were challenged with RSV-A. Quantitative viral assessments were consistently lower in active than pbo. The primary endpoint of the study was met: the area under the curve (AUC) for RSV VL over time (via qRT-PCR) was significantly lower in active pbo (P = 0.012). Median peak VL was lower for active (0 log10 copies/mL) than pbo (5.4 log10 copies/mL). Median AUC for RSV VL over time (quantitative culture) was lower for active than pbo (0 vs. 109, P = 0.002). Disease severity was lower for active than pbo, with a median AUC total symptom score of 35 (active) vs. 167 (pbo) (P = 0.002). Overall, RSV infection (defined by qRT-PCR alone or combined with symptoms) and disease severity over time were lower in active vs. pbo. Conclusion RSV infections, VL, and RSV disease severity were consistently lower in healthy adults receiving Ad26.RSV.preF vs. placebo, demonstrating promising protection from RSV infection and disease. This was the first time that antiviral prevention was observed against RSV after active immunization. Ad26.RSV.preF warrants further evaluation in field trials for efficacy against natural RSV infections in populations considered at risk of severe RSV disease. Disclosures All Authors: No reported Disclosures.


2019 ◽  
Vol 4 (1) ◽  
pp. 73
Author(s):  
Yayah Rukiah ◽  
Nurulfatmi Amzy ◽  
Angga Kusuma Dawami

<strong>Abstract</strong><br />The Changes of Singgalang Newspaper Logo. Logo becomes an inseparable identity in introducing a brand to society in general. The construction of the shape represents the identity in itself to show the entity and become a characteristic that is finally known to the target audience. Changes to the logo are based on the need for the entity to always make a new appearance to be better known and to imprint the meaning of the<br />entity in the minds of consumers. As one of the National newspapers, the Singgalang daily also changed its logo from the beginning of its publication in 1969. Changes in form that corresponded to Singgalang’s identity brought a different perception between one logo and another. The shapes differ from the first logo to the online media logo, indicating that Singgalang has special characteristics to show himself to the general<br />public. This article discusses the development of the Singgalang Daily logo that was published for the first time, until the logo is displayed in online media. The results of this study used the semiotic-Sumbo Tinarbuko approach, to see logos as symbols that exist and continue to make changes over time. By using semiotic analysis, the results of<br />this study show that logos are important for re-branding to get into the community in general.<br /><br /><strong>Abstrak</strong><br />Perubahan Logo Harian Singgalang. Logo merupakan salah satu identitas yang tidak terpisahkan dalam mengenalkan sebuah merek kepada masyarakat secara umum. Konstruksi bentuk merepresentasikan identitas dalam dirinya untuk menunjukkan entitasnya dan menjadi ciri khas yang akhirnya dikenal kepada target pembacanya. Perubahan logo didasari pada kebutuhan entitas untuk selalu membuat tampilan baru agar lebih dikenal dan lebih menancapkan makna bentuk entitasnya di benak konsumen. Sebagai salah satu koran nasional, Harian Singgalang juga melakukan perubahan logo dari awal terbitnya di 1969. Perubahan bentuk yang sesuai dengan identitas Singgalang membawa persepsi yang berbeda antar satu logo dengan logo yang lain. Bentukbentuknya<br />yang berbeda dari logo pertama sampai logo media daringnya, menandakan Singgalang memiliki ciri khusus untuk menunjukkan dirinya kepada masyarakat umum.Tulisan ini membahas tentang perkembangan logo Harian Singgalang yang terbit pertama kali, sampai logo yang ditampilkan di media daring. Hasil penelitian ini menggunakan pendekatan semiotika-Sumbo Tinarbuko, untuk melihat logo sebagai<br />sebuah simbol yang ada dan terus dilakukan perubahan dari waktu ke waktu. Dengan menggunakan analisis semiotika, hasil penelitian ini memperlihatkan bahwa logo menjadi penting untuk dilakukan desain ulang (re-branding) untuk dapat masuk ke masyarakat secara umum.


2017 ◽  
Vol 754 ◽  
pp. 35-38 ◽  
Author(s):  
S.M.J. Razavi ◽  
M. Peron ◽  
J. Torgersen ◽  
F. Berto

The problem of mixed mode (I+III) brittle fracture of polycrystalline graphite is investigated systematically here for the first time. The present study considers cylindrical specimens weakened by circumferential notches characterized by different acuities. A new complete set of experimental data is provided considering different geometrical configurations by varying the notch opening angle and the notch tip radius. The multiaxial static tests have been performed considering different values of the mode mixity ratio. A criterion based on the local Strain Energy Density previously applied by the same authors only to pure modes of loading is extended here to the case of tension and torsion loadings applied in combination.


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