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2022 ◽  
Author(s):  
Dmitry Valerievich Moskovchenko ◽  
Evgeny Babkin ◽  
Maria Pogojeva ◽  
Ruslan Zhostkov ◽  
Aleksandr Ovsyuchenko ◽  
...  

Abstract The composition of soils and their parent materials were studied within one of the most northern land areas of the world – the island of Alexandra Land of the Franz Josef Land archipelago. Contents of 65 trace and major elements were determined using atomic emission spectrometry (ICP-AES) и inductively coupled plasma spectrometry (ICP-MS). Other analyzed characteristics included soil pH, particle-size distribution and contents of carbon and nitrogen. The mineralogical composition of rocks was determined in thin sections. The studied soils were formed on basalts with high contents of MgO, Fe2O3, TiO2, Сu, Co, V, Ni, Cr, Zn, and low contents of Pb and Hg. The composition of soils was generally similar to that of the bedrock. The median concentrations (mg kg-1) of trace elements in the soils were as follows: Cu - 160, Zn - 101, Ni - 74, Pb - 2.9, Cd - 0.14, and Hg - 0.031. The bedrock had an alkaline pH, whereas the soil pH ranged from weakly acid to alkaline. The textural class of the soils predominantly corresponded to sandy loam. The contents of clay and silt increased with depth due to the migration of these fractions with groundwater. The concentrations of ecologically hazardous Hg and Pb were slightly increased in the upper layer of soils and correlated with carbon contents, which was indicative of bioconcentration processes.


Biology Open ◽  
2022 ◽  
Author(s):  
Takuma Kozono ◽  
Miwa Tamura-Nakano ◽  
Yuki I. Kawamura ◽  
Takashi Tonozuka ◽  
Atsushi Nishikawa

Tuft cell is a chemosensory cell, a specific cell type sharing the taste transduction system with a taste cell on the tongue, of which the existence has been known in various tissues such as gastrointestinal tract, gall bladder, trachea, pancreatic duct, etc. To date, electron microscopic approaches have shown various morphological features of the tuft cell such as long and thick microvilli, tubulovesicular network at the apical side, prominent skeleton structures, etc. Recently, it has been reported that the small intestinal tuft cell functions to initiate type2 immunity in response to helminth infection. However, the mechanisms by which such distinguished structures are involved with the physiological functions are poorly understood. To address this question, the combination of physiological study regarding the tuft cells using genetic models and its morphological study using electron microscopy will be required. However, it is a challenge to observe tuft cells by electron microscopy due to their extremely low frequency on the epithelium. Therefore, in this paper, we suggest the advanced protocol to observe the small intestinal tuft cell efficiently by transmission electron microscopy using serial semi-thin sections on the Aclar film.


Author(s):  
Ahmed A. Radwan ◽  
Bassem S. Nabawy

AbstractIn this study, it is aimed to characterize the Early pliocene sandstone (EP-SD) and the Late Miocene-Early Pliocene Mangaa sandstone reservoirs and the efficiency of their sealing cap rocks using the petrographical and petrophysical data of these sandstone zones in northern Taranaki basin, New Zealand. The prospective potential reservoirs were studied using impregnated thin sections, XRD data analysis, and well log data (self-potential, gamma-ray, sonic, density, neutron, shallow\deep resistivity and PEF) to characterize the reservoir zones, in addition to Mercury intrusion capillary pressure data (MICP) to check the efficiency of some potential seals. The EP-SD and the Mangaa sandstone units are typically poorly consolidated very fine sandstone to siltstone, with porosities averaging 25%. The sands are composed of quartz (38.3–57.4%), with common feldspars (9.9–15.2% plagioclase, and 2.7–6.3% K-feldspars) and up to 31.8% mica. In Albacore-1 well to the north of the Taranaki Basin, the Mangaa formation includes three separate for each of the EP-SD zones (EP-SD1, EP-SD2, and EP-SD3), and the Mangaa sequence (Mangaa-0, Mangaa-1, and Mangaa-2). The thin section studies indicate that, the studied samples are grouped into greywackes, arenites and siltstone microfacies with much lithic fragments and feldspars, sometimes with glauconite pellets. From the XRD data, it is achieved that the mineral composition is dominated by quartz, mica/illite, feldspars, and chlorite. The petrophysical investigation revealed absence of pay zones in the EP-SD zones, and presence of thin pay zone with net thickness 5.79 m and hydrocarbon saturation of about 25.6%. The effective porosities vary between 23.6 and 27.7%, while the shale volume lies between 12.3 and 16.9%. Although the shale content is relatively low, the relatively high API (50–112 API of average 75 API) is contributed by the relatively high K-feldspar content and intercalations with thin siltstone and muddy siltstone beds. Sealing units include the intra-formational seals within the Mangaa sequence, mudstones and fine grained units overlying the Mangaa and further intra-formational mudstones, within the shallower EP-SD units. The efficiency of these seals indicates the capability to trap 16.4–40.6 m gas or 17.4–43.0 m oil which is relatively low in correlation with their efficiency in the central parts of the Taranaki Basin Overlying the primary seals, mudstones of the Giant Foresets Formation provide additional regional seal.


2022 ◽  
Vol 29 (1) ◽  
Author(s):  
Alessia Nava ◽  
Patrick Mahoney ◽  
Luca Bondioli ◽  
Alfredo Coppa ◽  
Emanuela Cristiani ◽  
...  

Virtual histology is increasingly utilized to reconstruct the cell mechanisms underlying dental morphology for fragile fossils when physical thin sections are not permitted. Yet, the comparability of data derived from virtual and physical thin sections is rarely tested. Here, the results from archaeological human deciduous incisor physical sections are compared with virtual ones obtained by phase-contrast synchrotron radiation computed microtomography (SRµCT) of intact specimens using a multi-scale approach. Moreover, virtual prenatal daily enamel secretion rates are compared with those calculated from physical thin sections of the same tooth class from the same archaeological skeletal series. Results showed overall good visibility of the enamel microstructures in the virtual sections which are comparable to that of physical ones. The highest spatial resolution SRµCT setting (effective pixel size = 0.9 µm) produced daily secretion rates that matched those calculated from physical sections. Rates obtained using the lowest spatial resolution setup (effective pixel size = 2.0 µm) were higher than those obtained from physical sections. The results demonstrate that virtual histology can be applied to the investigated samples to obtain reliable and quantitative measurements of prenatal daily enamel secretion rates.


Metabolomics ◽  
2022 ◽  
Vol 18 (1) ◽  
Author(s):  
Margaret L. Dahn ◽  
Hayley R. Walsh ◽  
Cheryl A. Dean ◽  
Michael A. Giacomantonio ◽  
Wasundara Fernando ◽  
...  

Abstract Introduction Aldehyde dehydrogenase 1A3 (ALDH1A3) is a cancer stem cell (CSC) marker and in breast cancer it is associated with triple-negative/basal-like subtypes and aggressive disease. Studies on the mechanisms of ALDH1A3 in cancer have primarily focused on gene expression changes induced by the enzyme; however, its effects on metabolism have thus far been unstudied and may reveal novel mechanisms of pathogenesis. Objective Determine how ALDH1A3 alters the metabolite profile in breast cancer cells and assess potential impacts. Method Triple-negative MDA-MB-231 tumors and cells with manipulated ALDH1A3 levels were assessed by HPLC–MS metabolomics and metabolite data was integrated with transcriptome data. Mice harboring MDA-MB-231 tumors with or without altered ALDH1A3 expression were treated with γ-aminobutyric acid (GABA) or placebo. Effects on tumor growth, and lungs and brain metastasis were quantified by staining of fixed thin sections and quantitative PCR. Breast cancer patient datasets from TCGA, METABRIC and GEO were used to assess the co-expression of GABA pathway genes with ALDH1A3. Results Integrated metabolomic and transcriptome data identified GABA metabolism as a primary dysregulated pathway in ALDH1A3 expressing breast tumors. Both ALDH1A3 and GABA treatment enhanced metastasis. Patient dataset analyses revealed expression association between ALDH1A3 and GABA pathway genes and corresponding increased risk of metastasis. Conclusion This study revealed a novel pathway affected by ALDH1A3, GABA metabolism. Like ALDH1A3 expression, GABA treatment promotes metastasis. Given the clinical use of GABA mimics to relieve chemotherapy-induced peripheral nerve pain, further study of the effects of GABA in breast cancer progression is warranted.


2021 ◽  
Vol 54 (2F) ◽  
pp. 36-47
Author(s):  
Amel Nooralddin ◽  
Medhat Nasser ◽  
Aboosh Al-hadidy

The Upper Campanian Hartha Formation represents potential Cretaceous hydrocarbon-bearing reservoir rocks across the Y and J oilfields northwestern Zagros Basin, northern Iraq. The study objective is depositional environment which affects reservoir properties by tool, lithofacies, core, thin section, and logs, using petrel (V.2016) and strat software, facies distribution, grains, and diagenetic processes control and enhance reservoir properties which can plan platform production and minimize risks in choosing production wells location at two fields scale The current study is concerned with lithofacies and microfacies of the Hartha Formation within two fields in northern Iraq. Several subsurface well-log data, core, and cutting samples have been used in order to prepare thin sections that were subjected to sedimentological (lithofacies, and grain-size) examination. The petrography investigation revealed five rock-units including Hr. 1, 2, 3, 4, and 5, the thickness of 89 m in the Y-A field and increasing to up to 140 m in the J-B field might be due to erosion or tectonic uplift of the topography in Y subbasin. Which is locally sub-basin within study fields western banks of Tigris river as gentle slope ramp depositional condition with Spectrum microfacies from lime-mudstone to packstone texture with rudest and benthic debris enhances by diagenesis, dolomitization, dissolution moldic porosity, fracture; dolostone is more effective in the upper section of the formation in A than B Wells. Many factors, such as cementation, compaction, and pore-filling autogenic minerals, decrease reservoir quality, and their effects are similar in wells A and B.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261915
Author(s):  
Rodrigo Leandro Tomassini ◽  
María Dolores Pesquero ◽  
Mariana Carolina Garrone ◽  
María Dolores Marin-Monfort ◽  
Ignacio Alejandro Cerda ◽  
...  

Rancho La Brea (California, USA) is the most emblematic Quaternary fossiliferous locality in the world, since both the high number and diversity of the specimens recovered and their excellent preservational quality. In the last decades, paleobiological and paleoecological knowledge of the different groups of mammals from this site has increased notably; however, some aspects have not yet been inquired or there is little information. In this work we provide information on one of the most abundant mammals of this site, the equid Equus occidentalis, based on the study, from osteohistological and histotaphonomic perspectives, of thin sections of different limb bones. On the one hand, from an osteohistological viewpoint, we observe that the distribution and characterization of bone tissues in the different skeletal elements are, in general lines, similar to that mentioned for other extant and extinct equids. Cyclical growth marks allowed us to propose preliminary skeletochronological interpretations. On the other hand, from a taphonomic viewpoint, we note that all the samples reflect an excellent preservation of the bone microstructure, slightly altered by different pre- and post-burial processes. The variations recorded evidence different taphonomic history and preservation conditions among pits. This is the first study including fossil material from Rancho La Brea exclusively based on the analysis of the bone microstructure features.


2021 ◽  
Vol 30 (4) ◽  
pp. 754-761
Author(s):  
Oleh A. Sukhov

A new species of green paleosiphonocladаl algae Kamaena gigantea from the Lower–lowermost Middle Mississippian sediments of the Donbas has been described. This species was distinguished from other representatives of the genus Kamaena Antropov by its extremely large size, tortuous shape of the thallus and convex partitions. The species belongs to an artificial taxonomic unit of the Kamaenae Shuysky tribe, 1985 , of the family Palaeoberesellaceae Mamet et Roux , a systematic grouping which is still controversial. The attribution of this family to green siphonocladal algae is controversial and quite conditional, the opinions of different authors being based on personal vision, and varying in range from the plant to the animal kingdom. A characteristic feature of the family is the tubular shape , the segments of which are connected by partitions with a large central pore, sometimes with additional small pores. The thallus wall (fossilized remains of the body) is porous or non-porous and has simple or branched pores. It has been emphasized that study of Paleoberezellides in thin sections, the sometimes fuzzy images of the typical material in publications and ignorance of other researchers’ publications have caused confusion and led to the selection of an unreasonably large number of genera and species within the family. It has been noted that in previous works, representatives of this species were mistakenly identified as Anthracoporellopsis Maslov, a genus characteristic of the Lower–Middle Pennsylvanian sediments. This erroneous definition was based mainly on general external similarity, a poorly illustrated description of the type species, and did not take into account the morphological features that were characteristic for the genus. It has been found that representatives of the new species had a rather limited stratigraphic distribution: the Upper Tournaisian (Dokuchaevskian horizon) and the Lower Visean (Hlybokian–Sukhinskian horizons), and the most similar specimens found in the Ural region in underlying Tournaisian sediments were, unfortunately, poorly illustrated and smaller in size and had a narrower thallus. It has been noted that a characteristic feature of the tribe Kamaenae Shuysky, 1985 was the tubular shape, its inter-segmental partitions were perpendicular to the walls and were at the approximately same interval from each other. It has been pointed out that representatives of the new species were found mainly in grainstones, packstones, and wackstones − organogenic-detrital limestones along with such groups of microfauna as echinoderms and ostracods, isolated spicules of sponges and remains of worms. The material for illustrations was mainly taken from the borehole74 (near the village of Rodnikove, Starobeshiv district, Donetsk region) , which most fully revealed the Lower–Middle Pennsylvanian deposits of the southern part of the Donbas. The knowledge of the systematic composition of the Early Carboniferous algoflora has been expanded. This has helped us to conclude that the tribe Kamaeneae Shuysky, 1985 ,includes 6 genera and at least 22 species that were found in the layers from the Early Devonian to the Early Visean of the Lower Carboniferous.


2021 ◽  
pp. 1-49
Author(s):  
Pengyuan Han ◽  
Xindong Diao ◽  
Wenlong Ding ◽  
Liyuan Zang ◽  
Qingxiu Meng ◽  
...  

The main type of oil and gas reservoir in the Xinhenan-Sandaoqiao area is buried hills. The distribution pattern and scale of reservoirs are obviously controlled by pre-Sinian basement strata. However, the lithologic combination and spatial distribution pattern of pre-Sinian basement in this area are still unclear. In this paper, the spatial distribution of pre-Sinian basement volcanic and metamorphic rocks is studied by using the method of multifactor comprehensive analysis. Firstly, the lithology and lithologic combination of igneous and metamorphic rocks are determined according to cores and thin sections. Guided by the seismic reflection characteristics of different lithologic combinations, different lithologic combinations are identified on the profile by combining the seismic reflection characteristics of single well and multiwell. Secondly, using cluster analysis technology, three seismic attributes sensitive to lithology are selected from 10 attributes, crossplots of three seismic attribute values are constructed, and the distribution range of attribute values corresponding to different lithologic combinations is defined for plane lithologic identification. Finally, the plane lithology distribution of the surface layer of pre-Sinian basement is described by combining plane and profile. Six distribution types were identified: deep metamorphic bedrock area in Kuqu depression, dynamic mixed metamorphic rock and intermediate-acidic intrusive rock area, metamorphic bedrock in thrust napple slopes area, thermal contact metamorphic rock area, intermediate-acidic intrusive rock area, dynamic metamorphic rock area and gneiss area in faulted uplift core.


2021 ◽  
Vol 5 (2) ◽  
pp. 150-160
Author(s):  
V. P. Andreev ◽  
◽  
V. M. Tsyrkunov ◽  
I. A. Kondratovich ◽  
◽  
...  

Background. Though thioacetamide (TAA)-induced liver fibrosis (LF) is recognized as a classical model of toxic liver damage, there is no literature data on the description of its successive stages of histological and ultrastructural changes in various cell populations involved in fibrosis. Objective. To conduct morphological monitoring of fibrosis formation in the liver of rats using the TAA model of LF based on histological and ultrastructural changes in hepatocytes and perisinusoidal lipocytes (HSC). Material and methods. The experiment was carried out on 18 sexually mature male rats. LF was modeled by intraperitoneal injection of 2% TAA solution at a dose of 10 ml / kg every other day. Light microscopy of semi-thin sections of the liver was performed, as well as electron microscopy of ultrathin sections. Results. The study of semi-thin sections of rat liver tissue from the control group showed a normal architecture of the parenchyma, a large number of HSCs containing large lipid droplets ("resting" phenotype), a very small amount of cytoplasmic matrix poor in membrane organelles. In the animals that were receiving TAA for 4 weeks, a mesenchymalepithelial transition of HSCs from the "resting" type to a fibrogenic state (fibrogenic phenotype) was recorded, that was accompanied by a gradual decrease in the number of retinol-containing drops and the appearance of fibroblastlike cells (FLC) in HSCs. In the animals, that were receiving TAA for 12 weeks, the pool of fibrogenic cells in the liver increased, a mesothelial-mesenchymal transition occurred, characterized by the mesothelial cell migration deeper into the parenchyma and their acquisition of a mesenchymal phenotype. Lipid containing activated FLC were also found in fibrous tissue around the central vein. Foci of hepatic tissue destruction caused by necrosis and apoptosis of hepatocytes were much more common. Conclusions. Administration of TAA induces liver fibrosis while histological and ultrastructural monitoring of the state of hepatocytes and HSCs allows to monitor all stages of fibrosis, clarifying the mechanisms of damage to intracellular organelles and variants of hepatocyte death. This model of LF in rats can be used to test new antifibrotic drugs.


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