Stone Samples Research Articles

The aryl hydrocarbon receptor pathway is a marker of lung cell activation but does not play a central pathologic role in engineered stone-associated silicosis.

Engineered stone-associated silicosis is characterised by a rapid progression of fibrosis linked to a shorter duration of exposure. To date, there is lack of information about molecular pathways that regulates disease development and the aggressiveness of this form of silicosis. Therefore, we compared transcriptome responses to different engineered stone samples and standard silica. We then identified and further tested a stone dust specific pathway (aryl hydrocarbon receptor [AhR]) in relation to mitigation of adverse lung cell responses. Cells (epithelial cells, A549; macrophages, THP-1) were exposed to two different benchtop stone samples, standard silica and vehicle control, followed by RNA sequencing analysis. Bioinformatics analyses were conducted, and the expression of dysregulated AhR pathway genes resulting from engineered stone exposure was then correlated with cytokine responses. Finally, we inhibited AhR pathway in cells pretreated with AhR antagonist and observed how this impacted cell cytotoxicity and inflammation. Through transcriptome analysis, we identified the AhR pathway genes (CYP1A1, CYP1B1 and TIPARP) that showed differential expression that was unique to engineered stones and common between both cell types. The expression of these genes was positively correlated with interleukin-8 production in A549 and THP-1 cells. However, we only observed a mild effect of AhR pathway inhibition on engineered stone dust induced cytokine responses. Given the dual roles of AhR pathway in physiological and pathological processes, our data showed that expression of AhR target genes could be markers for assessing toxicity of engineered stones; however, AhR pathway might not play a significant pathologic role in engineered stone-associated silicosis.

Enhancing hyperspectral imaging through macro and multi-modal capabilities

Hyperspectral imaging (HSI) has emerged as an effective tool to obtain spatially resolved spectral information of artworks by combining optical imaging with spectroscopy. This technique has proven its efficacy in providing valuable information both at the large and microscopic scale. Interestingly, the macro scale has yet to be thoroughly investigated using this technology. While standard HSI methods include the use of spatial or spectral filters, alternative methods based on Fourier-transform interferometry have also been utilised. Among these, a hyperspectral camera employing a birefringent common-path interferometer, named TWINS, has been developed, showing a high robustness and versatility. In this paper, we propose the combination of TWINS with a macro imaging system for the study of cultural heritage (CH). We will show how the macro-HSI system was designed, and we will demonstrate its efficient capabilities to collect interferometric images with high visibility and good signal of both reflectance and fluorescence on the same field of view, even on non-flat samples. Our hyperspectral camera for macro studies of both reflectance and fluorescence data is a completely new asset in the CH panorama and beyond. The relevance of the macro technology is demonstrated in two case studies, aiding in the analysis of biofilms on stone samples and of the degradation of dyed textiles.

The influence of multi-scale tough liquid fiber toughening agent on the mechanical properties of oil well cement-based composite materials

Cementing is a key process in drilling engineering, and the cement sheath in cementing can sometime have problems such as significant brittleness, low toughness, and low resistance to impact damage, especially in perforation and fracturing environments where the cement sheath is more susceptible to damage. In response to the above issues, three types of inorganic carbon fibers, including 1 mm carbon fiber, 2 mm carbon fiber, and nanocarbon fiber, were studied indoors to investigate the influence of their ratios on the mechanical properties of cement paste. The optimal mixture of 1 mm carbon fiber, 2 mm carbon fiber, and nanocarbon fiber in a ratio of 3:2:1 was selected, and a multi-scale liquid fiber toughening agent BS-54 was obtained through special liquefaction process treatment. The liquid fiber toughening agent BS-54 has good water dispersibility and can evenly disperse in the slurry water, effectively improving the dispersion and addition of multi-scale fibers in cement slurry. The cement slurry prepared with multi-scale dispersed liquid fiber toughening agent has good rheological properties, water loss, and thickening properties. The addition of multi-scale dispersed liquid fiber toughening agent to cement slurry significantly increases the tensile strength, impact strength, and compressive strength of cement paste, effectively reduces the elastic modulus of cement paste, improves the strength of cement paste, and achieves toughening effect. Microscopic analysis shows that the active nanoparticles dispersed by multi-scale dispersed liquid fiber toughening agents can interweave between gaps, and the dense cross-linked structure formed by their multi-scale micro nano structure improves the toughness and strength of cement slurry. Moreover, the multi-scale dispersed liquid fiber toughening agent cement slurry ensures that the cement stone sample has good integrity under external impact, which is conducive to improving the impact resistance of the cement stone.

REMEDIATION OF OIL-CONTAMINATED SOILS WITH COMPOSITIONS BASED ON HUMIC ACIDS

In addition to conventional methods, nowadays new approaches and technologies based on combined application of sorbents and microorganisms are intensively developed for efficient control of oil contaminations. As a biotechnological solution for remediation of various oil-contaminated soils, biocompositions based on an organic matrix – humic acids of peat, and a biological component – a single strain/or an association of oil degrading microorganisms of the genera Rhodococcus and Pseudomonas, have been studied. The efficiency assessment of oil contamination biodegradation using biocompositions was carried out on different types of model oil-contaminated soils with different levels of contamination: grey forest soil, Black Sea pebbles (fraction 20-50mm), constructional broken stone (fraction 10-20mm). Natural soil contaminated with oil products and samples of railroad broken stone (fractions 5-30mm and 35-50mm) were also used. It has been shown that the biocompositions based on three strains of microorganisms – ‘HA R. X5 R. S67 Ps. NF142' – possessed the highest capability of degrading oil hydrocarbons in all systems under study. Biodegradation of oil hydrocarbons upon addition of this biocompositions varied between 62 and 82% depending on the type of oil-contaminated soil, the level of contamination being very high. Monobacterial biocomposition ‘HA Ps.NF142’ has proven to be promising for remediation of oil-contaminated soil ecosystems with a high and very high level of contamination. The increase of the level of biodegradation of oil contamination of soils appears to be due to the combined action of humic acids comprising both the stimulating effect of humic acids on microorganisms – the components of biocompositions and indigenous microflora of model systems, and the detoxifying effect of humic acids in respect of oil hydrocarbons. For citation: Grechishcheva N.Yu., Dmitrieva E.D., Starodubtseva K.A. Remediation of oil-contaminated soils with compositions based on humic acids. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 136-143. DOI: 10.6060/ivkkt.20246707.6927.

Combined activity of blue vitriol, brimstone and black stone on clinical Candida species isolates using fractional inhibitory concentration Index

Combination antimicrobial therapy (CAT) involves intentional addition of two or more antimicrobial agents for better therapeutic outcome. CAT is normally applied for treatment of polymicrobial infections, life-threatening infections and prevention of the emergence of resistance. This research aimed at determining the combined activity of blue vitriol, brimstone and black stone on clinical Candida species isolates using Fractional Inhibitory Concentration Index. The brimstone, blue vitriol and black stone samples were purchased from a community market in southeastern Nigeria. The isolates were obtained from high vaginal swab samples of patients attending a Teaching hospital in Nigeria and identified based on their morphological, physiological and molecular characteristics. The minimal inhibitory concentrations (MIC) of the samples were determined using the broth dilution method. The fractional inhibitory concentration indexes (FICI) of the samples against the isolates were obtained from their individual FIC values. FICI of <1 indicates synergism; 1 to 2 (Indifference); while >2 (antagonism). All the test agents were synergistic against C. albicans (FICI < 1). All the test agents were indifferent against C. tropicalis (FICI 1 - 2). Brimstone + black stone combination was indifferent (FICI 1 - 2) against C. glabrata; while all the test agents were antagonistic against the isolate (FICI > 2). Blue vitriol + Black stone combination was antagonistic (FICI > 2) against C. parapsilosis; Blue vitriol + brimstone was indifferent (FICI 1 - 2); while brimstone + black stone was synergistic (FICI < 1). The findings have revealed that antimicrobial combination outcome could be synergistic, antagonistic or indifferent; thus the need for proper in vitro screening before combination therapy.

The key role of major and trace elements in the formation of five common urinary stones

BackgroundUrolithiasis has emerged as a global affliction, recognized as one of the most excruciating medical issues. The elemental composition of stones provides crucial information, aiding in understanding the causes, mechanisms, and individual variations in stone formation. By understanding the interactions between elements in various types of stones and exploring the key role of elements in stone formation, insights are provided for the prevention and treatment of urinary stone disease.MethodsThis study collected urinary stone samples from 80 patients in Beijing. The chemical compositions of urinary stones were identified using an infrared spectrometer. The concentrations of major and trace elements in the urinary stones were determined using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), respectively. The data were processed using correlation analysis and Principal Component Analysis (PCA) methods.ResultsUrinary stones are categorized into five types: the calcium oxalate (CO) stone, carbonate apatite (CA) stone, uric acid (UA) stone, mixed CO and CA stone, and mixed CO and UA stone. Ca is the predominant element, with an average content ranging from 2.64 to 27.68% across the five stone groups. Based on geochemical analysis, the high-content elements follow this order: Ca > Mg > Na > K > Zn > Sr. Correlation analysis and PCA suggested significant variations in the interactions between elements for different types of urinary stones. Trace elements with charges and ionic structures similar to Ca may substitute for Ca during the process of stone formation, such as Sr and Pb affecting the Ca in most stone types except mixed stone types. Moreover, the Mg, Zn and Ba can substitute for Ca in the mixed stone types, showing element behavior dependents on the stone types.ConclusionThis study primarily reveals distinct elemental features associated with five types of urinary stones. Additionally, the analysis of these elements indicates that substitutions of trace elements with charges and ion structures similar to Ca (such as Sr and Pb) impact most stone types. This suggests a dependence of stone composition on elemental behavior. The findings of this study will enhance our ability to address the challenges posed by urinary stones to global health and improve the precision of interventions for individuals with different stone compositions.

Monitoring changes in hydric properties of treated stone material with conservation products by time-sequential IR thermography

A methodological approach for a semi-quantitative non-destructive testing (NDT) of the effects on hydric properties after the application of different conservation treatments (commercial ethylsilicate and siloxane compounds with consolidant, water repellent or consolidant + water repellent properties) is presented in this study. The NDT used for this purpose is a simplified method of time-sequential infrared thermography (IRT) on stone (granite and marble, treated and untreated) from the Roman theatre of Merida (Spain), which was listed by UNESCO as World Heritage Site in 1993.As water evaporation modifies temperature intensely, IRT enables monitoring the response of the stone samples during water absorption-evaporation processes. The comparative analysis between treated and non-treated specimens was performed by calculating the rate of surface apparent temperature change (ΔoC/h) value. The capillary rising test, monitored by IRT, clearly showed a different response of the samples treated with water-repellent treatments, proving their efficiency. Samples treated with organosilicic compounds showed a large and rapid drop in apparent surface temperature, indicating that water accesses rapidly.Results from the evaporation test also show this difference. The surface apparent temperature increased immediately in samples with water-repellent treatments, in which water does not enter inside stone, but remains on the surface. Samples with ethyl silicate, again, show a greater difference with respect to untreated samples, taking longer to recover surface apparent temperature, because the water is retained inside the stone for longer.This study proved simplified time-sequential IRT as a reliable technique for assessing the efficacy of conservation treatments applied to stone materials in laboratory.

Dystrophic calcinosis: structural and morphological composition, and evaluation of ethylenediaminetetraacetic acid (‘EDTA’) for potential local treatment

BackgroundTo perform a detailed morphological analysis of the inorganic portion of two different clinical presentations of calcium-based deposits retrieved from subjects with SSc and identify a chemical dissolution of these deposits suitable for clinical use.MethodsChemical analysis using Fourier Transform IR spectroscopy (‘FTIR’), Raman microscopy, Powder X-Ray Diffraction (‘PXRD’), and Transmission Electron Microscopy (‘TEM’) was undertaken of two distinct types of calcinosis deposits: paste and stone. Calcinosis sample titration with ethylenediaminetetraacetic acid (‘EDTA’) assessed the concentration at which the EDTA dissolved the calcinosis deposits in vitro.ResultsFTIR spectra of the samples displayed peaks characteristic of hydroxyapatite, where signals attributable to the phosphate and carbonate ions were all identified. Polymorph characterization using Raman spectra were identical to a hydroxyapatite reference while the PXRD and electron diffraction patterns conclusively identified the mineral present as hydroxyapatite. TEM analysis showed differences of morphology between the samples. Rounded particles from stone samples were up to a few micron in size, while needle-like crystals from paste samples reached up to 0.5 µm in length.Calcium phosphate deposits were effectively dissolved with 3% aqueous solutions of EDTA, in vitro. Complete dissolution of both types of deposit was achieved in approximately 30 min using a molar ratio of EDTA/HAp of ≈ 300.ConclusionsStone and paste calcium-based deposits both comprise hydroxyapatite, but the constituent crystals vary in size and morphology. Hydroxyapatite is the only crystalline polymorph present in the SSc-related calcinosis deposits. Hydroxyapatite can be dissolved in vitro using a dosage of EDTA considered safe for clinical application. Further research is required to establish the optimal medium to develop the medical product, determine the protocol for clinical application, and to assess the effectiveness of EDTA for local treatment of dystrophic calcinosis.

ВЛИЯНИЕ СУПЕРПЛАСТИФИЦИРУЮЩИХ ДОБАВОК НА ОСНОВЕ ЭФИРА ПОЛИКАРБОКСИЛАТА НА ТЕХНОЛОГИЧЕСКИЕ И ФИЗИКО-ТЕХНИЧЕСКИЕ СВОЙСТВА ГИПСОЦЕМЕНТНО-ПУЦЦОЛАНОВОГО ВЯЖУЩЕГО

Effective modifiers of the structure and properties of concrete based on gypsum-cement-pozzolanic binder are chemical additives. Among a wide range of chemical additives, superplasticizing additives can be distinguished. The most effective in terms of water-reducing effect, increasing the mobility and strength of concrete based on gypsum-cement-pozzolanic binder are superplasticizers based on polycarboxylate ethers. The paper presents studies of the influence of superplasticizing additives on the physical and technical properties of gypsum-cement-pozzolanic binder based on low-grade gypsum and cement binders, and a binary active mineral additive consisting of zeolite-containing marl and microsilica. It has been shown that the introduction of the studied modifiers makes it possible to improve the performance properties of products based on gypsum-cement-pozzolanic binder, which is expressed in an increase in compressive strength and an increase in water resistance. Patterns of changes in water demand, setting time, and water-reducing effect of the gypsum-cement-pozzolanic binder mixture were obtained when it is modified with polycarboxylate additives of the following grades:“Melflux 2651 F”, “Polyplast type S”, “Polyplast type R”, “SPS-06”, “SPS-08”, “DK-100” and C-3 in comparison with unmodified HCPV, the change in strength with compression and softening coefficient of gypsum-cement-pozzolanic binder stone with these additives. It has been established that reducing the water requirement of the gypsum-cement-pozzolanic binder mixture by 60 % increases the compressive strength of gypsum-cement-pozzolanic binder stone samples by 33.5 MPa compared to the control composition. It has been shown that the most effective modifiers among those studied are “Polyplast type S” and “DK-100”.

Strength characteristics and energy evolution of cement stone under true-triaxial loading conditions

Oil well cement is a commonly used cementing material in oil and gas extraction engineering. Due to the change of stress conditions, it is prone to microcracks or micro annular gaps, leading safety concerns. To study the strength characteristics and energy evolution of oil well cement stone under three-dimensional stress states, a series of true-triaxial compression tests were carried out. Based on the experimental results, the mechanical properties and energy evolution mechanisms during the true-triaxial compression process of cement stone under different stress states were explored. The research results indicate that there is an intermediate principal stress effect on the true-triaxial compressive strength of cement stone specimens. When the minimum principal stress remains constant, the strength of cement stone first increases and then decreases with the increase of intermediate principal stress. When the minimum principal stress is 5 MPa, the specimen exhibits brittle failure, with ε1 at peak stress approximately 0.015. As the minimum principal stress increases to 20 MPa, the specimen gradually transits to plastic failure, with ε1 at failure exceeding 0.04. The type of failure is determined by the energy ratio at the time of failure; when there is more elastic energy, it results in brittle failure, otherwise it leads to ductile failure. Due to the high porosity of cement stone samples, most of the input energy is converted into dissipated energy. At minimum principal stresses of 5 MPa, 10 MPa and 20 MPa, the ratio of peak dissipated energy to total input energy fluctuates around 0.55, 0.73 and 0.85, respectively. There is a strong linear relationship between the peak elastic energy, peak dissipated energy, and total input energy, with fitting correlation coefficients of 0.847 and 0.996, indicating that the cement stone sample also follows the linear energy storage law. A strength criterion for cement stone was established based on the modified Lade criterion, which is more suitable for describing the strength of high porosity materials compared to traditional strength criteria. Finally, based on the interaction mechanism between energy accumulation and energy dissipation, a nonlinear model of energy evolution in cement stone was established. The results of the theoretical model are in good agreement with the experimental data.

Microbiomic association between the saliva and salivary stone in patients with sialolithiasis

Salivary stones, known as sialoliths, form within the salivary ducts due to abnormal salivary composition and cause painful symptoms, for which surgical removal is the primary treatment. This study explored the role of the salivary microbial communities in the formation of sialoliths. We conducted a comparative analysis of microbial communities present in the saliva and salivary stones, and sequenced the 16S rRNA gene in samples obtained from patients with sialoliths and from healthy individuals. Although the diversity in the saliva was high, the essential features of the microbial environment in sialoliths were low diversity and evenness. The association of microbial abundance between stones and saliva revealed a positive correlation between Peptostreptococcus and Porphyromonas, and a negative correlation for Pseudomonas in saliva. The functional potential differences between saliva and stones Bacterial chemotaxis and the citrate cycle were negatively correlated with most genera found in salivary stone samples. However, the functions required for organic compound degradation did not differ between the saliva samples. Although some microbes were shared between the sialoliths and saliva, their compositions differed significantly. Our study presents a novel comparison between salivary stones and salivary microbiomes, suggesting potential preventive strategies against sialolithiasis.

Characterization of biliary and duodenal microbiota in patients with primary and recurrent choledocholithiasis.

To explore the biliary and duodenal microbiota features associated with the formation and recurrence of choledocholithiasis (CDL). We prospectively recruited patients with primary (P-CDL, n = 29) and recurrent CDL (R-CDL, n = 27) for endoscopic retrograde cholangiopancreatography (ERCP). Duodenal mucosa (DM), bile and bile duct stones (BDS) samples were collected in P- and R-CDL patients. DM samples were also collected in 8 healthy controls (HC). The microbiota profile analysis was performed with 16S rRNA gene sequencing. Short-course antibiotic application before ERCP showed no significant effects in alpha and beta diversities of the biliary and duodenal microbiota in CDL. Alpha diversity showed no difference between DM and bile samples in CDL. The duodenal microbial richness and diversity was lower in both P- and R-CDL than HC. The biliary microbiota composition showed a high similarity between P- and R-CDL. Fusobacterium and Enterococcus were higher abundant in DM, bile, and BDS samples of R-CDL than P-CDL, as well as Escherichia and Klebsiella in bile samples of R-CDL. The enriched duodenal and biliary bacteria in CDL were closely associated with cholecystectomy, inflammation and liver dysfunction. The bile-associated microbiota of R-CDL expressed enhanced capacity of D-glucuronide and D-glucuronate degradation, implicating an elevated level of β-glucuronidase probably produced by enriched Escherichia and Klebsiella in bile. The duodenal microbiota was in an imbalance in CDL. The duodenal microbiota was probably the main source of the biliary microbiota and was closely related to CDL formation and recurrence. Enterococcus, Fusobacterium, Escherichia and Klebsiella might contribute to CDL recurrence. The study was registered at the Chinese Clinical Trial Registry (https://www.chictr.org.cn/index.html,ChiCTR2000033940). The online version contains supplementary material available at 10.1007/s13755-023-00267-2.

Community-Acquired Infection among the Hospitalized Renal Stone Patients

Abstract Background One of the most prevalent long-term kidney disorders in high-blood-pressure patients is nephrolithiasis. This study involves collecting urine and renal stones from patients with urinary tract infection (UTI) to analyze how hospitalized patients with UTI contract community infections. The samples were collected at the Sulaimaniyah Surgical Teaching Hospital urology and extracorporeal shock wave lithotripsy (ESWL) staff. It is understood that UTIs contribute to the formation of kidney stones. Methods Screened and cultured urine requires careful collection, transport, and interpretation. Urine samples were collected from the patients with UTI at the Sulaimaniyah teaching hospital for culturing. Urine cultures containing pyuria and bacteria indicate UTIs. Microorganisms were studied, inoculated on blood, MacConkey, and mannitol salt agar, and biochemically identified. A bacterial and microbiological examination of kidney stones was conducted at the Sulaymaniyah Surgical Teaching Hospital's ESWL and urology departments. Clean renal stone samples with ethanol for 1 minute, crush using sterile tongs, then culture in 37°C thioglycolate broth for 48 hours. Specimens inoculated on blood, MacConkey, and mannitol salt agars resulted in isolation of staphylococci, streptococci, and Staphylococcus spp. Results In this study, 17 of 48 samples showed microbial growth. Each of Enterococcus and Micrococcus spp. comprised 12.5% of eight renal intact stone samples. Three of 14 renal intact stone samples showed microbial growth with 7 and 14% for Enterococcus and Escherichia coli, respectively. From eight urine samples before and after ESWL procedure, E. coli isolation incidents doubled from 12.5 to 25%, while Staphylococcus spp. remained the same at 12.5%. Out of 10 UTI urine samples, 20% Staphylococcus spp., E. coli, and 10% Pseudomonas spp. were isolated. Conclusion This study related renal stones to E. coli, enterococci, Micrococcus luteus, and staphylococci. After ESWL, the urine samples revealed E. coli growth, whereas comparable urine samples before ESWL did not. Thus, urinary infections can cause kidney stones. Eighteen of 48 kidney stone samples tested positive for E. coli, 22 for staphylococci, 11 for enterococci, 5 for Pseudomonas, 5 for Proteus, and 5 for micrococci.

Study of the Determination of Three-Point Flexural Strength Loading in Resin and Reinforcing Ornamental Stones

Theoretical framework: Brazil is one of the world's largest producers of ornamental stones, and is therefore the richest country in granite diversity in the world. Improvements in processing and production techniques have been developed over the years to add value to the final product. The resistance of stones is a preponderant factor for their application in certain environments. Some stone industries try to improve the resistance of the material by resining or reinforcing (resin plus fiberglass mesh) on their material. Method/project/approach: the work studied the behavior of resined and reinforced stones (resin plus fiberglass mesh). three-point flexural strength tests were carried out on pegmatite stones and quartzites. They were divided into groups with just resin and others with resin plus fiberglass mesh. Results and conclusion: The results showed that in the group of Pegmatite stones it was possible to obtain a gain of up to 44% in material resistance when resined and reinforced. However, the Quartzites did not have a significant gain, in some cases they obtained a lower value when reinforced. Only one of the quartzites achieved a 14% gain in resistance. Therefore, it is necessary to carry out a preliminary study with laboratory tests before resining and reinforcing the ornamental stones for sold. Research implications: Compare the three-point flexural strength between samples of pegmatic and quartzite stones and evaluate the resistance of reinforced (resin plus fiberglass mesh) and resin (resin) stones. Originality/value: analyze the influence of resin and fiberglass mesh on the three-point flexural strength of ornamental stones.

Physical and γ-ray shielding properties of Vietnam's natural stones: An extensive experimental and theoretical study

The current work deals with investigation of the gamma ray shielding properties for various natural stones from Vietnam to be applied in the radiation shielding applications. The physical and chemical properties affecting the γ-ray shielding performance were examined. The MH-300A density meter was utilized to measure the density (ρ, g/cm3) of stone samples, as well as the chemical composition of Vietnamese natural stones was measured using the X-ray fluorescence analyzer (Olympus X-5000). The study shows that the increase in Fe + Ca concentrations within the stone samples increases their density (from 2.48 to 2.86 g/cm3) accompanied with a reduction in the porosity (Φ, %) (from 8.23 to 0.15%) and water absorption (K, %) (from 3.42 to 0.05%) factors. Additionally, the increase in Fe + Ca concentrations increases the linear attenuation coefficient (μ, cm−1) of the studied stones, where the Vietnamese marble stone (M 3.1) with the highest Fe + Ca concentration (65.97 wt%) has the highest linear attenuation coefficient which varied between 3.781 and 0.155 cm−1 with raising the gamma ray energy between 0.040 and 1.332 MeV.

Investigation on radiation attenuation properties of natural stone samples traded in Turkey

Although radioprotection is globally regulated for high radiation exposure, formal guidelines concerning natural radiation exposure that causes stochastic radiation effects have not been established. The commonly used absorbers lead, tungsten and bismuth are not appropriate for the radioprotection of the public. The primary barrier against natural radiation is the structural components of buildings, where humans spend approximately 80 % of their lifetime. Natural stones are secondary materials, which are applied to walls and floors as coating. This study focuses on the radiation shielding properties of natural stones. Herein, the samples of marble, granite and sedimentary rock traded in Turkey were examined to determine whether they can serve as passive or alternative radioprotection materials. Notable gamma absorption rates were obtained when an intense gamma source with an energy of 662 keV was used. The calculated mass attenuation coefficients were comparable with those of copper and aluminium. The mean mass attenuation coefficient was 0.082 cm2/g for marbles and granites and 0.080 cm2/g for sedimentary rocks. Considering the stochastic effects, the use of the natural stones as construction materials is anticipated to significantly reduce the natural radiation level in inhabitable regions. Furthermore, natural stones can be used in clinics as secondary radiation shields against low-energy gamma and x-rays.

Relative and absolute difference in soil organic carbon stocks in grassland soils in Ireland: Impact of rock fragments, bulk density and calculation methods

On-farm management measures can sequester carbon by removing carbon dioxide from the atmosphere and storing it securely for long periods, in our soils. Estimates of soil organic carbon (SOC) stocks differ by calculation methods in terms of how they account for the coarse >2 mm fraction (i.e. rock fragments) of the soil. Irish grassland soils have variable volumetric stone contents and the extent of overestimation is unknown. Without best practice guidance, calculations of SOC in these soils are vulnerable to overestimation. The objectives of the present study for grassland soils in Ireland were to: 1) calculate mean SOC stocks using different methods by soil horizon and volumetric stone content class; 2) highlight relative differences in SOC stocks between these calculation methods and 3) compare normalised layer (Ly, fixed depth) versus horizon (Hz) type derived sampling data in terms of SOC stocks, to establish a best practice standardised sampling protocol. Five methods (M, 1–3 overestimate SOC stocks, whereas 4–5 are equivalent and are closest to reality) to calculate SOC stocks were used in combination with three soil databases i.e. Irish Soil Information System (I-SIS), the Heavy Soils Programme (HSP) and the Soil Quality Assessment Research Project (SQUARE). Objectives 1 and 2 were assessed using all three databases across methods, whereas objective 3 used the SQUARE database and M4. These data were sorted into volumetric stone content (%) classes (< 5%, 5–10%, 10–20%, 20–30% and > 30%) and sampling horizon (O, A, E, A/B, B, B/C, and C) with SOC stocks calculated using M1–5 equations. Results confirmed the high volumetric stone content assumption of grassland soils in Ireland (exception O horizons). Volumetric stone contents ranged from 0% to 36% for all horizons. When M1–5 are considered the average relative difference in SOC stocks between M1 and M5 was 18.9% (max: 388%), M2 and M5 was 7.7% (max: 60.7%) and M3 and M5 was 8.9 (max: 310%). In terms of Ly versus Hz sampling, no significant differences were found for the A horizons sampled. However, in Ireland, best practice should still utilise elements from both Ly (using an auger to get fixed depth soil samples; analysed for organic C) and Hz (using a soil profile pit to extract representative BD cores and to gather bulk samples for volumetric stone content analysis) approaches in the field. Laboratory methods used must fit with the needs and assumptions of equations M4/5 to calculate SOC stocks (thereby minimising overestimation and indeed underestimation).

Natural Deep Eutectic Solvents as Rust Removal Agents from Lithic and Cellulosic Substrates.

The peculiar physicochemical features of deep eutectic solvents (DESs), in particular their tunability, make them ideal media for various applications. Despite their ability to solubilize metal oxides, their use as rust removers from valuable substrates has not yet been thoroughly investigated. In this study, we chose three known DESs, consisting of choline chloride and acetic, oxalic or citric acid for evaluating their ability to remove corrosion products from a cellulose-based material as linen fabric and two different lithotypes, as travertine and granite. The artificial staining was achieved by placing a rusty iron grid on their surfaces. The DESs were applied by means of cellulose poultice on the linen fabrics, while on the rusted stone surfaces with a cotton swab. Macro- and microscopic observations, colorimetry and SEM/EDS analysis were employed to ascertain the cleaning effectiveness and the absence of side effects on the samples after treatment. Oxalic acid-based DES was capable of removing rust stains from both stone and cellulose-based samples, while choline chloride/citric acid DES was effective only on stone specimens. The results suggest a new practical application of DESs for the elimination of rust from lithic and cellulosic substrates of precious and artistic value.

The effect of glycerin-painted wax pattern on surface quality of dental stone mold

Aim: The aim of this study was to examine the effects of glycerin-coated wax patternon dental stone surface quality in terms of surface roughness and micro airbubble formation.Method: In this study, a total of 20 modeling wax samples were used for thehydrophilicity test (the contact angle test) divided into 2 groups (control andglycerin-painted). A total of 20 dental stone samples were also prepared forvisual and microscopic analysis divided into 2 groups (control and glycerinpainted).Results and conclusion: The contact angle data showed a significant decrease insurface hydrophilicity for the glycerin-painted group (P-value &lt; 0.05). However,the visual and microscopical analysis did not show a prominent distinction insurface quality between the two groups, so there is no noticeable effect on dentalstone surface caused by glycerin-modified wax pattern.

Factors effecting the success of retrograde intrarenal surgery in pediatric patients with renal stones: The experience of two tertiary centres with 368 renal units

Currently, in the field of pediatric urology, the primary aim of surgical approaches for the treatment of renal stone disease is to provide a stoneless state through minimally invasive methods, and to prevent the damage that such stones may cause in the urinary system and stone recurrence. The aim of this study was to evaluate the efficacy and safety of RIRS and the factors affecting its success in the surgical treatment of renal stones in pediatric patients. Data from 357 pediatric and 368 renal units were collected retrospectively. The recorded parameters were age, gender, location and burden of the stone, and presence of postoperative residual stones. The stone location was the upper pole in 28 (7.6%) patients, the middle pole in 44 (12%), the pelvis in 98 (26.6%), the lower pole in 139 (37.8%), and multiple locations in 59 (16%) patients. A stoneless state was achieved in 277 (75.3%) units, while 91 units (24.7%) had residual stones at the end of the first month. In the multivariate analysis, the development of residual stones was found to be significantly associated with age (odds ratio [OR], 1.123; p=0.012) and stone location (OR, 3.142; p=0.018). RIRS is an endourological procedure with a high success rate in the achievement of a stoneless state in both pediatric and adult age groups, with an 82-100% success rate reported in various studies. A full stoneless state was achieved in 277 (75.3%) units after the initial RIRS in the present study, and full stone clearance was achieved in 304 units after the second RIRS session, with a success rate of 82.6%. A limitation of our study is that it was not performed by a single surgeon, and stone samples could not be taken from all patients for stone analysis. RIRS has also been associated with a high success rate in the endoscopic treatment of renal stones and is an efficient and safe method with a minimal rate of complications, especially in the pediatric age group.