Calcareous Concretions Research Articles

Comment on Gazi et al. (2020): Detecting Coral Reef Degradation on St. Martin’s Island, Bangladesh?

St. Martin’s Island is a small sedimentary island situated at the southernmost part of Bangladesh (20°37.6′ N and 92°19.3′ E). The island is surrounded by rocky reefs composed of Neogene bedrock consisting of moderately hard and soft sandstones and conglomerates belonging to the Tipam Sandstone (Islam in Bangladesh J Univ Sheffield Geol Soc 7:269–275, 1980). The rocky reefs are covered by fields of conglomerate boulders and calcareous concretions that provide a suitable substrate for coral settlement and the establishment of coral communities. Before 1997 it was reported that St. Martin’s Island was a coral island surrounded by coral reefs (Ahmed in Bangladesh J Environ Sci 1:67–73, 1995; Anwar in National workshop on coastal area resource development and management, Part II. CARDMA, BRAC Printers Bangladesh, Dhaka, pp 36–66, 1988; UNEP/IUCN in Indian Ocean, Red Sea and Gulf. UNEP regional seas and bibliographies. IUCN, Gland, 1988). However, the first underwater survey conducted in 1997 did not find any evidence of coral reefs (Tomascik in Management plan for coral resources of Narikel Jinjira (St. Martin's Island). National Conservation Strategy Implementation Project-1, Ministry of Environment and Forest, Government of the People’s Republic of Bangladesh, p 125, 1997). The island has become an important tourism destination and concerns have been raised about the impact of local development on its coral resources (Tomascik 1997). Recently a paper was published on the degradation of coral reefs on St. Martin’s Island (Gazi et al. in Ocean Sci J 55(3):419–431, 2020) that makes many factually incorrect assertions. The rocky reefs that surround the island have been misclassified by Gazi et al. (2020) as “coral reefs”. Here, we discuss Gazi et al. (2020) and examine if the results and conclusions provide factual evidence of spatiotemporal coral reef degradation.

Comparison of in-source solid bitumen with migrated solid bitumen from Ediacaran-Cambrian rocks in the Upper Yangtze region, China

In-source solid bitumen was found in some cracks within the calcareous concretion in an overmature (Rbitumen > 3.5%) black shale of the Lower Cambrian Niutitang Formation from Songtao, Guizhou, China. The solid bitumen (grain size >2 cm) concentrated in source rock, which was formed by the transformation of petroleum-like substances that have not been expelled from source rock. This provides a substitute for studying the physical and chemical properties of in-situ solid bitumen, which usually occurs as finely dispersed particles in black shale. On the other hand, Ediacaran-Cambrian carbonate rocks (which serve as reservoir in the area) contain pyrobitumen derived from petroleum that migrated from the black shale of the Niutitang Formation.A comparative petrological and geochemical analysis was conducted on the in-source solid bitumen from the Lower Cambrian Niutitang Formation and the migrated solid bitumen in the Ediacaran-Cambrian carbonate rocks. The in-source solid bitumen displays a relatively homogeneous optical structure with very weak anisotropy and is visibly different from the migrated bitumen in the Ediacaran-Cambrian carbonate reservoir. This migrated bitumen in the reservoir displays strong anisotropy and optical structure similar to that of coke. Considering a strata like the lower Palaeozoic in South China, which has no vitrinite and is highly over mature, the in-source solid bitumen is likely to be the most suitable organic component for measuring the reflectance and subsequently determining the thermal maturity of organic matter.Interestingly, the in-source solid bitumen displays some inheritance of its parent material. The stable carbon isotope ratios are very similar to those of kerogen in the black shales (approximately −34‰ to −33‰), and the distribution pattern of the trace elements and rare earth elements (REEs) is consistent with that of the Niutitang black shales. The distribution patterns of the trace elements and REEs in the migrated bitumen are basically consistent with those of in-source solid bitumen, however, their stable carbon isotope composition is slightly heavier (−33.6‰ to −31.2‰) than that in the source rocks. In other words, as a key link in the chain, the in-source solid bitumen could connect the migrated bitumen in the reservoir with its source rock. This provides direct support for tracing oil and gas sources in the area by using the element geochemical characteristics of migrated solid bitumen in reservoir.

Origin, growth, and characteristics of calcareous concretions in the varved sediments of a Glacial Lake

A comprehensive study is presented of the characteristics of calcareous concretions in the Connecticut Valley varved clay (CVVC), a glacial lake sediment, probed by an array of investigations, including compositional analyses via X-ray powder diffraction and energy-dispersive X-ray spectroscopy, mechanical property mapping by nanoindentation, selective dissolution, microstructure examination by optical and electron microscopy, and stable isotope analyses, with an objective to resolve some long-standing questions on their origin and growth mechanisms. Results show that these concretions are of a biogenic origin and consist of ~40 wt% primary host sediments and ~ 60 wt% secondary calcite post-depositionally precipitated as pore infills and inter-particle cement. The highly consistent layering and dry density between the carbonate-free host sediments in the concretions and in-situ varved sediments manifest that the precipitated calcite causes no disturbance to the original stratification and structure of the varved sediments. Moreover, both the mechanical properties (i.e., Young's modulus and hardness) and calcite concentration in concretions exhibit a radially decreasing pattern slightly disturbed by the sediments' layered textures. Further supported by the radial distribution patterns of stable carbon and oxygen isotopes, the CVVC concretions grow in a concentric pattern. A conceptual ion transport model is proposed to further interpret the growth mechanisms. These concretions grow radially in a nearly closed sediment system with diffusion-controlled transport of HCO3− from decaying organic matter and Ca2+ from porewater at direction-dependent rates dominated by the pore characteristics of the local host sediments. The diverse concretion morphologies are attributed to the different growth rates in different directions affected by the heterogeneous layering and pore sizes of the host sediments.

Taphonomy and systematics of decapod crustaceans from the Aptian (Lower Cretaceous) in the Oliete Sub-basin (Teruel, Spain)

Decapod crustaceans from the Forcall Formation (Aptian, Lower Cretaceous) of the Oliete Sub-basin (Maestrazgo Basin) are recorded, specimens having been collected from the localities of Josa and Obón (Teruel) in the Aragonese branch of the Iberian Cordillera, northeast Spain. The glypheid lobster Atherfieldastacus magnus is by far the commonest species at several stratigraphical levels. Minor components of the decapod crustacean fauna include axiidean shrimps (Aptaxiopsis longimanus gen. et sp. nov., Crosniera forcallensis sp. nov., Meticonaxius gracilis sp. nov., Aptanacalliax enigma gen. et sp. nov.), a glypheidean lobster (Meyeria ornata), a hermit crab (Cretacocalcinus josaensis gen. et sp. nov.) and a brachyuran, Mithracites vectensis Gould, 1859. Meticonaxius gracilis nov. sp. represents the oldest fossil record of this genus to date. Aptanacalliax enigma gen. et sp. nov. and Crosniera forcallensis sp. nov. are considered to be the earliest occurrences of the families Anacalliacidae and Callianideidae, respectively, at this date. The specimens studied document two different modes of preservation, which also have an impact on the diversity of each assemblage. Our collections include specimens preserved within calcareous concretions and those preserved in mudstones. The assemblages studied are considered parautochthonous, i.e., were preserved within or close to their habitat and were entombed by obrution events that accumulated sediment and bioclastic material within an offshore setting.

Calcite-Mineralized Fossil Wood from Vancouver Island, British Columbia, Canada

Calcite-mineralized wood occurs in marine sedimentary rocks on Vancouver Island, British Columbia at sites that range in age from Early Cretaceous to Paleocene. These fossil woods commonly have excellent anatomical preservation that resulted from a permineralization process where calcite infiltrated buried wood under relatively gentle geochemical conditions. Wood specimens typically occur in calcareous concretions in feldspathic clastic sediment. Other concretions in the same outcrops that contain abundant mollusk and crustacea fossils are evidence that plant remains were fluvially transported into a marine basin. Fossiliferous concretions commonly show zoning, comprising an inner region of progressive precipitation where calcite cement developed as a concentric halo around the organic nucleus. An outer zone was produced by pervasive cementation, which was produced when calcite was simultaneously precipitated in pore spaces over the entire zone.

Trace fossils and palynomorphs in Holocene calcareous concretions from Lake Selbusjøen, Mid-Norway: Post-glacial environmental records

Trace fossils and palynomorphs are recorded for the first time in Holocene calcareous concretions from Lake Selbusjøen, Central Norway. The described trace fossils can be assigned to the Mermia ichnofacies, characterizing lake deposits with good oxygenation and low depositional energy. The predominance of simple grazing trails and shallow burrows (e.g. Cochlichnus, Helminthoidichnites and Treptichnus) in silty and sandy concretions possibly represent relatively low-energy sublittoral parts of the lake, while the occurrence of Vagorichnus and Arenicolites in sandy substrate points to littoral and shallow sublittoral areas with moderate depositional energy. The trace fossils and palynomorph assemblages from Lake Selbusjøen appear to relate to periods of climatic warming during Pre-Boreal times, and possibly also Atlantic times.

Sialolithiasis leading to sialadenitis- A case report

Sialolithiasis is the obstruction of salivary gland due to blockage of its excretory duct in response to the formation of calcareous concretions which causes the dilation of salivary gland. Sialadenitis is an acute infection of salivary gland. Sialadenitis is seen mostly in parotid gland and sialolith is mostly reported in sub-mandibular gland. We hereby report a case of elderly female with an acute pain on left sub-mandibular region which was diagnosed as sub-mandibular sialolithiasis leading to sialadenitis. Keywords: Sialolithiasis, Sialadenitis, Calculi, Conservative management.

Hydrocarbon-seep deposits in the lower Permian Angie Formation, Central Lhasa Block, Tibet

Methane seepage along continental margins has been linked to climatic warming, yet it is uncertain whether such seepage took place during the Permian, a period that witnessed a transition from an icehouse to a greenhouse world. To address this issue, we investigated calcareous concretions and layers within mudstones/shales of the Kungurian Angie Formation in the Xainza area, central Tibet. A combination of petrographic, mineralogical, elemental, and carbon‑sulfur isotopic analyses provide strong evidence for a hydrocarbon-seep origin of these carbonates, with thermogenic methane and crude oil being the most likely carbon sources. Our dataset also indicates that, although fueled by a common deep-buried hydrocarbon reservoir, these layers and concretions experienced different biogeochemical processes due to variable rates of cold-seep fluid flux combined with persistently low sulfate concentrations in bottom waters of the Bangong-Nujiang Tethyan Ocean. A biogeochemical switch from sulfate-dependent to iron oxide-coupled anaerobic oxidation of methane in the sulfate-methane transition zone, likely triggered by sulfate exhaustion, was inferred to affect carbonate layer formation near the sediment-water interface. If true, this switch, together with common vent structures, would have resulted in escape of large amounts of methane directly to the ocean-atmosphere system. The hydrocarbon seeps in the central Lhasa Block was approximately coeval with rapid climate warming in the peri-Gondwanan region during the early Kungurian. Although further investigations are required in the future, this study demonstrates a possible causal relationship between regional tectonic evolution, hydrocarbon seepage, and global climate change.

In situ observations on the dentition and oral cavity of the Neanderthal skeleton from Altamura (Italy).

The Neanderthal specimen from Lamalunga Cave, near Altamura (Apulia, Italy), was discovered during a speleological survey in 1993. The specimen is one of the most complete fossil hominins in Europe and its state of preservation is exceptional, although it is stuck in calcareous concretions and the bones are mostly covered by calcite depositions. Nevertheless, it is possible to carry out some observations on craniodental features that have not previously been described. In this work, we present an account of the oral cavity, made possible by the use of a videoscope, which allowed us to reach some hidden parts of the mandible and palate. This is the first detailed overview of the teeth and maxillary bones of the Neanderthal skeleton from Altamura. The dentition is almost complete. However, two teeth (upper right P3 and upper left M1) were lost ante mortem and four teeth (lower right I1 and P3 and lower left I1 and I2) were lost most probably post mortem. Dental wear is marked. The erupted M3s and the inversion of the compensating curve of Wilson in the M1s and M2s but not in the M3s suggest that the individual is fully adult, but not old. Although most of the teeth have their roots exposed for several millimeters, the periodontal bone appears to be in good condition overall, except in correspondence of the two ante-mortem tooth losses. X-rays of the anterior teeth show a periapical lesion, probably linked to the advanced dental wear. We also observed a weak expression of taurodontism in the posterior dentition and the presence of a retromolar space, features consistent with an attribution to the Neanderthal hypodigm; this attribution is also supported by aspects of the cranial morphology, the morphometric analysis of the scapula and preliminary mtDNA data. There is also a well-developed palatine torus, to the best of our knowledge a feature not previously described in Neanderthals.

Geo-environmental suitability assessment for tunnel in sub-deep layer in Zhengzhou

ABSTRACT In order to better provide geological basis for the rail transport planning in Zhengzhou, the geo-environmental suitability assessment for tunnel in sub-deep layer was carried out. In the study, the multi-objective linear weighted function method and analytic hierarchy process were used to evaluate the suitability of geological environment. The results show that the index affecting the geological environment suitability of tunnel in sub-deep layer in the study area mainly include the enriched layer of calcareous concretions, the weighted average compressive modulus, the standard deviation of compression modulus and the content of chloride ion in groundwater. The area with poor suitability of geological environment is mainly distributed in the southeast of the study area. During the construction in this area, the influence of the enriched layer of calcareous concretions and the stratum with poor uniformity on operation should be considered. The moderate suitability of geological environment is mainly consistent with the distribution of the enriched layer of calcareous concretions. Other areas in the study area are the good suitability of geological environment. In the future, the data precision in the evaluation should be improved, utilization of underground space should be got by remote sensing, and a relative-independent evaluation index system and dynamic evaluation model should be established.

U–Pb dating of calcite in ancient carbonates for age estimates of syn- to post-depositional processes: a case study from the upper Ediacaran strata of Finnmark, Arctic Norway

AbstractResults of in situ U–Pb dating of calcite spherulites, cone-in-cone (CIC) calcite and calcite fibres from a calcareous concretion of the upper Ediacaran of Finnmark, Arctic Norway, are reported. Calcite spherulites from the innermost layers of the concretion yielded a lower intercept age of 563 ± 70 Ma, which, although imprecise, is within uncertainty of the age of sedimentation based on fossil assemblages. Non-deformed CIC calcite from the bottom part of the concretion yielded an age of 475 ± 25 Ma, which is interpreted as the age of CIC calcite formation during a period of fluid overpressure induced during burial of the sediments. Deformed CIC calcite from the top part of the concretion yielded an age of 418 ± 23 Ma, which overlaps with a known Caledonian tectono-metamorphic event, and indicates a potential post-depositional overprint at this time. Calcite fibres that grew in small fissures along spherulite rims, which are interpreted as a recrystallization feature during deformation and formation of a cleavage, gave an imprecise age of 486 ± 161 Ma. Our results show that U–Pb dating of calcite can provide age constraints for ancient carbonates and syn- to post-depositional processes that operated during burial and metamorphic overprinting.

First articulated stalked crinoids from the Mesozoic of South America: two new species from the Lower Cretaceous of the Neuquén Basin, west-central Argentina

AbstractTwo new isocrinids are described from the Lower Cretaceous Agrio Formation of the Neuquén Basin, west-central Argentina. Isocrinus (Chladocrinus) covuncoensis new species is based on several beautifully preserved specimens from Valanginian beds of the Pilmatué Member. It is characterized by a small size, multiramose crown with six arm divisions, 240 arm tips, mostly isotomous branching, seven (or rarely eight) secundibrachials, smooth and stout column, short noditaxis, and pentalobate columnals. The species occurs in a 30 m thick interval of cross-bedded sandstones and mixed clastic-carbonate sediments that represent the migration of large, tidally influenced, subaqueous dunes developed in the offshore. Sudden burial of crinoids that dwelled on the dune toes and interdunes, possibly by the acceleration of the lee face migration, provided the exceptional preservation of specimens and thus this finding can be considered as a local crinoid Konservat Lagerstätte. Isocrinus (Chladocrinus) pehuenchensis new species is described from a single articulated specimen preserved in a silty calcareous concretion collected from a late Hauterivian concretion level of the Agua de la Mula Member. It is characterized by isotomous branching, eight or nine secundibrachials (IIBr), slender column ornamented with medial ridge of fine tubercles, interradius acuminated with fine tubercles on its tip, short noditaxis, and pentastellate columnals. It is associated with low-energy fall-out deposits in the offshore. The excellent state of preservation was due to an early cementation process by carbonate that enhanced lithification around the specimen.UUID: http://zoobank.org/4763ae70-9d0a-4015-b1c9-6a7ceeedfb1a

Sialolithiasis in a 19 year old male: A case report

Sialolithiasis is a condition characterized by the obstruction of a salivary gland or its excretory duct due to the formation of calcareous concretions, resulting in salivary ectasia and subsequent dilatation of the salivary gland. This disease is mostly seen in adults or young adults, and seldom develops in children with submandibular gland duct being the most common site. This case report describes a 19 year old patient presenting with pain and swelling in right side of floor of mouth. Sialolithiasis of right submandibular gland was diagnosed based on clinical and radiographic examination. The sialolith was removed under local anesthesia. Keywords: Sialolithiasis, Submandibular gland, Intraductal, Intraglandular, Sialo-MRI, Lithotripsy.

Rare earth element (REE) enrichment of the late Ediacaran Kalyus Beds (East European Platform) through diagenetic uptake

The Kalyus Beds of the late Ediacaran Nagoryany Formation occurring in the northeastern part of the Republic of Moldova are dominated by black argillites with phosphorites and calcareous concretions. Four lithological groups were examined with respect to their rare earth element (REE), major and trace element geochemistry: phosphorites, enriched argillites, pure argillites and carbonates. Phosphorites and enriched argillites exhibit a pronounced middle-REE bulge suggesting a strong diagenetic uptake of REEs. Y/Ho ratios are mostly <35, values that are consistent with derivation of >90% of REEs from lithogenous sources. Pure argillites show a flat REE distribution similar to that of average upper continental crust (UCC), indicating that REEs are likely related to detrital siliciclastics derived from felsic to mafic source rocks of the adjacent regions of Baltica, which was isolated within paleo-oceans during the late Ediacaran. Carbonates show a light-REE depleted pattern with relatively high Y/Ho ratios (up to 53) that suggests the preservation of a predominantly hydrogenous (seawater-derived) REE signal. Ce/Ce* ratios of ∼0.80–1.02 reflect suboxic to anoxic seawater conditions. This is a locally and temporally constrained anoxic event, since widespread oxic conditions were specific for the continental margins of Baltica. The phosphorites and enriched argillites groups of the Kalyus Beds show high middle-REE enrichment comparable to those of other known world phosphorite deposits. Their total REE contents are high (793–1735 ppm) and are of potential economic interest. These results provide insights for expanding global REE exploration targets and may have implications for a better understanding of the depositional environments during the late Ediacaran.

Rhinolith causing unilateral chronic rhinosinusitis: a case report

&lt;p class="abstract"&gt;Rhinolith or nasal stone is formed by mineralization within nasal cavity. They are calcareous concretions that are formed by the deposition of salts on an intranasal foreign body. It is an uncommon disease that may present asymptomatically or cause symptoms like nasal obstruction, consecutive sinusitis with or without purulent rhinitis, post nasal discharge, epistaxis, anosmia, nasal malodour and headache. They are usually diagnosed incidentally on radiographic examinations or depending on the symptoms. In this paper we report a 28-year-old woman admitted in the ENT department of GGS Medical College and Hospital, Faridkot with a calcified mass in the right nasal cavity causing long standing unilateral nasal obstruction for 3 years, rhinorrhoea (usually malodourous foetid), post nasal discharge and headache for 1 year. The calcified mass was thought to contain the air cell and removed by endonasal approach. The aim of this study is to report a case of rhinolith with chronic maxillary sinusitis along with a review of literature.&lt;/p&gt;

Análise da ação de ácidos sobre ictiólitos da Formação Santana, Cretáceo Inferior da Bacia do Araripe, Nordeste do Brasil

Fossils are of great importance for building knowledge of the history of life on Earth. However, it demands a careful handling from its collecting at the field to curatorship in laboratory and its incorporation in a collection. Preparation, a part of that process, evolves the removal of the fossils from the rock matrix, through mechanic and/or chemical attrition. Despite the relevance of such procedure, the access to its knowledge keeps itself relatively restricted to paleontology laboratories, lacking such type of publications. Then, this work was realized aiming to test the utilization of different types and concentrations of acids in preparation process of calcareous fossils. The tests with acetic, hydrochloric, phosphoric and sulfamic acids were executed in twelve fragments of calcareous concretions (ichthyolites) of the Santana Formation, Lower Cretaceous of the Araripe Basin. Acetic acid had showed itself the most appropriated for the treatment of calcareous concretions for its elongated and soft action.

Thermally-induced cracks and their effects on natural and industrial geomaterials

Thermal stress can result in significant changes in the mechanical and transport properties of building materials, especially in terms of cracking. Three building materials were studied: two concretes, a siliceous and a calcareous one, and a natural calcareous rock, the Tuffeau. The samples were subjected to thermal shock, repetitive heating-cooling cycles, and high temperature heating in order to analyze the effects of maximum temperature, cooling rate, and repetitive heating on the three materials. The induced cracks were then characterized by physical and hydraulic measurements, namely elastic wave velocities, porosity and effective thermal conductivity. Elastic wave velocities were used to determine crack density while effective thermal conductivity was used to determine crack connectivity. Cracks were also quantitatively described through direct microstructural observations using scanning electron microscopy. Results show the effectiveness of the different protocols in inducing cracks. Unexpectedly, repetitive heating-cooling cycles caused the most significant sample damage, whatever the sample. A second main result is based on the comparison of the different materials. It was found that the behavior of the two concretes was very similar: the stronger the thermal treatment, the more the crack density and connectivity increased, albeit with a slight difference in that the siliceous concrete appeared to be less resistant to sharp thermal variations. This is interpreted as being linked to microstructural effects: in the siliceous concrete, we observed cracks that nucleated around and inside grains, but not in the calcareous concrete. Lastly, the behavior of the Tuffeau limestone was different from that of the concretes: when crack density increased, the crack connectivity and the porosity both decreased. This different behavior is interpreted in the light of microstructural observations of the crack apertures: the thermally induced cracks in Tuffeau are too small to influence the effective thermal connectivity measurement and to allow fluid flow during the porosity measurement, whereas in the concretes, cracks were observed to be much more open. As an outlook, we discuss a possible equivalent test to the normalized fire protocol, performed at high temperature, to test the fire resistance of materials.

Physicochemical investigation of shrimp fossils from the Romualdo and Ipubi formations (Araripe Basin).

The Ipubi and Romualdo Formations are Cretaceous units of the Araripe Basin (Santana Group). The first and most ancient was deposited in a lake environment, and some fossils were preserved in shales deposited under blackish conditions. The second was deposited in a marine environment, preserving a rich paleontological content in calcareous concretions. Considering that these two environments preserved their fossils under different processes, in this work we investigated the chemical composition of two fossilized specimens, one from each of the studied stratigraphic units, and compared them using vibrational spectroscopy techniques (Raman and IR), X-ray diffraction and large-field energy-dispersive X-ray spectroscopy (EDS) mappings. Calcite was observed as the dominant phase and carbon was observed in the fossils as a byproduct of the decomposition. The preservation of hydroxide calcium phosphate (Ca10(PO4)6(OH)2, hydroxyapatite) was observed in both fossils. In addition, it was observed that there was a smaller amount of pyrite (pyritization) in the Romualdo Formation sample than in the Ipubi one. Large-field EDS measurements showed the major presence of the chemical elements calcium, oxygen, iron, aluminum and fluoride in the Ipubi fossil, indicating a greater influence of inorganic processes in its fossilization. Our results also suggest that the Romualdo Formation fossilization process involved the substitution of the hydroxyl group by fluorine, providing durability to the fossils.

Hystrix brachyura Bezoar Characterization, Antioxidant Activity Screening, and Anticancer Activity on Melanoma Cells (A375): A Preliminary Study.

Porcupine bezoars (PBs) are masses of undigested calcareous concretions formed within the gastrointestinal tract. There are undocumented claims that PBs have antioxidant activity and can treat cancers. However, limited scientific study has been carried out to verify these traditional claims. Hence, this study was conducted to characterize the chemical profile and validate the antioxidant and anticancer activity against melanoma cells (A375). PB extract was initially subjected to Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GCMS), total phenolic content (TPC), and total flavonoid content (TFC) analyses. The bioautography of antioxidant assays, namely 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH), and β-carotene was performed. An in vitro A375 cell viability assay, apoptosis assay, cell cycle arrest assay, and gene expression assay were carried out as well. The experimental finding revealed 5,10-diethoxy-2,3,7,8-tetrahydro-1H,6H-dipyrrolo[1,2-a:1′,2′-d]pyrazine, ursodeoxycholic acid, and cholest-5-en-3-ol (3 beta)-, carbonochloridate are major compounds detected in PB extract. PB extract has low phenolic content, viz. 698.7 ± 0.93 (µg GAE/5 mg dry weight). The bioautography antioxidant assays revealed a potent antioxidant effect (ABTS > DPPH > β-carotene), with free radical scavenging activity. Furthermore, PB extract exhibited dose- and time-dependent inhibition of cancer activity on A375 cells due to the exhibition of apoptosis via an intrinsic pathway.

Physical and Mechanical Properties of Sandstone and Calcareous Concretions at the Wave-Cut Bench in Iwami-tatamigaura, a Natural Monument in Shimane, Japan

Physical and Mechanical Properties of Sandstone and Calcareous Concretions at the Wave-Cut Bench in Iwami-tatamigaura, a Natural Monument in Shimane, Japan