Wear phenomena on natural stone of the cultural heritage are induced from various sources. Consequently, the development of multifunctional protective materials which combine two or more useful properties is an effective strategy to address the synergistic effects of various wear mechanisms. A multifunctional coating, consisting of a silane-based precursor and zinc oxide (ZnO) nanoparticles (NPs), is produced and tested for the protection of limestone. The hybrid coating combines the following three properties: superhydrophobicity, including water-repellency, photocatalytic self-cleaning and biocidal activity. The relative concentration of the NPs (0.8% w/w), used for the suggested composite coating, is carefully selected according to wetting studies, colourimetric measurements and durability (tape peeling) tests. The non-wetting state is evidenced on the surface of the composite coating by the large contact angle of water drops (≈153°) and the small contact angle hysteresis (≈5°) which gives rise to the physical self-cleaning scenario (lotus effect). The photocatalytic chemical self-cleaning is shown with the removal of methylene blue, induced by the UV-A radiation. Moreover, it is shown that the suggested coating hinders the incubation of E. coli and S. aureus as the inhibition were 94.8 and 99.9 %, respectively. Finally, preliminary studies revealed the chemical stability of the suggested coating.

• Book : ()
• Pub. Date : 2024
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Abstract. Accurate and continuous measurements of atmospheric carbon dioxide (CO2) are essential for climate change research and monitoring of emission reduction efforts. NASA's Orbiting Carbon Observatory (OCO-2/3) satellites have been deployed to measure the column-averaged CO2 dry air mixing ratio (XCO2) with very high precision. Although cloudy measurements are screened out, nearby clouds can still cause retrieval biases because the forward one-dimensional (1D) radiative transfer (RT) model used in the OCO retrieval algorithm does not account for the scattering induced by clouds in the vicinity of the OCO-2/3 footprints. These biases, referred to as the three-dimensional (3D) effects, can be quantified effectively using 3D-RT calculations, but these are computationally expensive, especially for hyperspectral applications (e.g., OCO-2/3). To reduce the prohibitive computational demands of 3D-RT radiance simulations across all three OCO spectral bands, this paper employs a linear approximation with two metrics (called slope and intercept) for each of the OCO bands that represent the 3D-RT perturbations on the OCO-2 spectra and accelerate the radiative transfer by a factor of 100. This is implemented by the Education and Research 3D Radiation Transfer Toolbox for OCO (EaR3T-OCO). EaR3T-OCO estimates OCO-2 satellite radiances using all available footprint-level data and imagery from the Aqua satellite, which orbits in close proximity to the OCO-2 satellite. EaR3T-OCO can calculate 3D-RT spectral perturbations for any OCO-2 footprint. These calculations can be used to spectrally adjust the OCO-2 radiance measurements with scene-dependent EaR3T-OCO perturbation calculations prior to the actual retrieval to undo cloud vicinity effects in the radiance spectra, which can subsequently be processed with the standard OCO-2 retrieval code. We find that this adjustment largely mitigates XCO2 retrieval biases in proximity to clouds over land – the first physics-based correction of 3D-RT effects on OCO-2/3 retrievals. Although the accelerated 3D-RT radiance adjustment step is faster than full 3D-RT calculations for all OCO spectral bands, it still requires at least as much computational effort as the XCO2 retrieval itself. To bypass 3D-RT altogether, the slope and intercept metrics are parameterized as a function of the weighted cloud distance of a footprint and several other scene parameters, all of which can be derived directly from Aqua-MODIS imagery. While this method is fastest and thus feasible for operational use, it requires careful validation for various surface and atmospheric conditions. For the case we analyzed, both the 3D-RT calculation method and the parametric bypass method successfully corrected XCO2 biases, which exceeded 2 ppm at the footprint level, and reached up to 0.7 ppm in the regional average. We find that the biases depend most strongly on the cloud field morphology and surface reflectance, but also on secondary factors such as aerosol layers and sun-sensor geometry.

• Book : ()
• Pub. Date : 2024
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In this letter, we propose a pattern-diversity antenna with different radiation patterns at two different frequency bands (f1 and f2) (f1: broadside radiation pattern, f2: conical radiation pattern). The proposed structure consists of a central circular antenna and two annular ring antennas; each of the three antennas has individual ports. Two of the ports exhibit orthogonal broadside radiation patterns; the other two ports exhibit orthogonal conical radiation patterns. Thus, they have polarization diversity characteristics. To improve isolation between ports, the inner part of the annular ring antennas is shorted via array, and the outermost port is positioned orthogonal to the other ports. Using this configuration, the isolation between ports was measured as -26.7 dB and -30.1 dB at the two frequency bands, respectively. Experimental results based on the fabricated prototype show that the proposed antenna achieves -10 dB bandwidths of 240 MHz (5.71~5.95 GHz) and 210 MHz (7.69~7.9 GHz) at f1 and f2, respectively.

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• Pub. Date : 2024
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AbstractPreserving biodiversity requires an understanding of how natural environments and anthropogenic factors shape the global distribution of biological diversity. Moving beyond a focus on endangered species, conservation needs to also preserve the typical interactions among species that structure communities, such as those found in mixed‐species bird flocks (MSBFs). The objective of this study is to quantify the α and β diversity of MSBFs on a global scale and explore the influence of environmental factors. Based on data compiled from 172 global publications encompassing 2095 MSBF participating bird species, we investigated the distribution patterns and influencing factors of MSBFs at different latitudes globally. The findings revealed that the species diversity of MSBFs is higher at lower latitudes. In terms of β diversity, MSBFs exhibit high‐turnover at mid to low latitudes and nested patterns at higher latitudes. Environmental factors positively influencing α and β species diversity of MSBFs included temperature and solar radiation, while wind speed and human disturbance negatively affected diversity. Based on the wide distribution and conservation significance of MSBFs, we provide quantifiable data on their global diversity patterns and suggest that future animal conservation management strategies should prioritize a community‐based approach focused on interspecific interactions.

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• Pub. Date : 2024
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Приводятся результаты исследований радиационного воздействия на искусственную нефть из нефтебитумной породы месторождения Кирмаку Азербайджана. Нефтебитумная порода это природный материал, образованный из нефти в верхних слоях земной коры в результате испарения из нее легких фракций, природной деасфальтизации нефти и процессов взаимодействия ее компонентов с кислородом. Из 375 г битуминозной породы было получено 50 мл искусственной нефти путем перегонки на аппарате Retort Heating Jacketпри температуре 950 F (510°C). Исследованы образование газов и изменение свойств жидких остатков при переработке искусственной нефти, полученной в лабораторных условиях, а также изучена радиационная стойкость различных фракций нефти из битуминозной породы. Исследования проводились при воздействии γ-излучения Со60 МРХ-γ-30 в широком интервале поглощенной дозы (43‒216 кГр) в воздухе и вакууме при мощности дозы Р=0,5 Гр/с. Представлены результаты хроматографического, хромато-масс-спектроскопического и ИК-спектроскопического исследований образцов искусственной нефти. Результаты таких исследований позволяют оценить возможность получения нефтепродуктов различного назначения радиационно-термическим способом из нефтебитумной породы, а также использование этих материалов для изоляции радиоактивных источников от окружающей среды. The results of studies of the radiation impact on artificial oil from the oil-bitumen rock of the Kirmaku field in Azerbaijan are presented. Petroleum bitumen rock is a natural material formed from oil in the upper layers of the earth's crust as a result of the evaporation of light fractions from it, the natural deasphalting of oil and the processes of interaction of its components with oxygen. From 375 g of bitumen rock, 50 ml of synthetic oil was obtained by distillation on a Retort Heating Jacket at a temperature of 950 F (510°C). The formation of gases and changes in the properties of liquid residues during the processing of artificial oil obtained in laboratory conditions have been studied, as well as the radiation resistance of various fractions of oil from bitumen rock has been studied.The studies were carried out under the influence of γ-radiation Co60 MRKH-γ-30 in a wide range of absorbed doses (43‒216 kGy) in air and vacuum. at dose rate Р=0.5 Gy/s. The results of chromatographic, chromatospectroscopic and IR spectroscopic studies of artificial oil samples are presented. The results of such studies make it possible to evaluate the possibility of obtaining petroleum products for various purposes using the radiation-thermal method from oil-bitumen rock, as well as the use of these materials to isolate radioactive sources from the environment.

• Book : 8(1)
• Pub. Date : 2024
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The purpose of this work is to improve the quality of medical services, to acquire financial benefits for hospitals, and to achieve beneficial social consequences. These are the goals and the motivations that are driving this work. Using the framework of deep learning, it studies the composition of medical linear accelerators, as well as their working principle, acceptance, and the routine quality assurance (QA) and quality control (QC) procedures. Additionally, it examines the acceptability of these applications. This article focuses on the acceptance items and detection procedures of accelerators, as well as common technological failures and solutions. In addition to providing a summary of emergency maintenance experience and analyzing the usual technical failures of medical electronic linear accelerators, it also provides an analysis of the common technical failures and solutions. Given that Chinese radiation institutions are already utilizing medical accelerators, the authors of this study analyze the relevant development state of medical electron linear accelerators as well as the future development trends of these accelerators. This is done in light of the fact that medical accelerators are currently being utilized by Chinese radiation institutes today. It provides further explanation on the unified implementation and refinement of its usage standards, in addition to providing information regarding conventional quality assurance and quality control. The findings provide a theoretical basis as well as a practical significance for the continued development of linear accelerators for use in medical applications in the future.

• Book : 05(03)
• Pub. Date : 2024
• Page : pp.834-846
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Aim: To evaluate patient satisfaction outcomes with respect to pain, discomfort, and quality of life with hematology/oncology referrals undergoing CT-guided bone marrow biopsy and compare these scores with those of patients undergoing in-office biopsy. Methods: A retrospective chart review was performed over 2 years with all patients who underwent CT-guided bone marrow biopsy at our university set-up. Age, gender, BMI, radiation dose (CTDI/DLP), number of in-office biopsies, number of CT-guided biopsies, type/amount of moderate sedation used, technical and pathologic success rates, and complication rates were recorded. All patients who underwent both in-office and CT-guided biopsy were contacted by telephone to answer a brief survey regarding pain, discomfort, quality of life, and future preference with respect to each biopsy. Results: A total of 32 patients underwent CT-guided bone marrow biopsy. Moderate sedation was utilized for all CT patients, and 19 patients underwent both in-office and CT-guided biopsies. Upon surveying the 19 patients who underwent both kinds of biopsies, on a scale of 1–10 (10 = highest discomfort and highest pain), the patients on an average reported 7.8 for in-office vs. 2.1 for CT for the discomfort level (p < 0.001) and 7.9 vs. 1.7 for the pain (p < 0.001). The patients reported an average quality-of-life score of 82 (out of a scale of 100) after CT procedures and 53 for in-office (p < 0.001). All patients reported that they would prefer CT-guided procedures with sedation versus in-office procedures in the future. Conclusion: CT-guided bone marrow biopsy is the preferred and more comfortable procedure, especially in low-pain-tolerant patients, although it involves more cost, conscious sedation, and radiation exposure.

• Book : 4(3)
• Pub. Date : 2024
• Page : pp.224-231
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Peanut (Arachis hypogaea L.), an economically valuable crop, provides protein and oil for human and animal consumption. The transcription factor MYB4 has been identified as a potential drought tolerance gene in peanut. This study aimed to isolate and characterize the MYB4 gene in the L14 peanut cultivar. The isolated AhL14_MYB4 gene was found to be 1.1 kb long, with a 663 bp coding sequence containing 3 exons and 2 introns. In silico analysis showed that AhL14_MYB4 possesses a nuclear localization signal and two DNA-binding domains characteristic of transcription factors. The findings revealed key molecular features of AhL14_MYB4 and provided insights into improving drought resistance in peanut varieties. Further research on AhL14_MYB4 may aid efforts to enhance drought tolerance in local peanut cultivars through molecular breeding or genetic engineering. Overall, this finding about preliminary characterization of the peanut MYB4 gene lays the groundwork for potential genetic improvements to this economically important crop.

• Book : 133(1B)
• Pub. Date : 2024
• Page : pp.5-11
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To safely dispose of nuclear waste in underground facilities, engineered barrier systems are needed to seal shafts and galleries. The material used in these barriers must be adapted to the host rock parameters. Shrinking and cracking must be avoided to provide a barrier with almost zero permeability. For repositories in salt rock environments, several types of salt concrete (SC) are used. Within the project SealWasteSafe, we compared the performance of an innovative alkali-activated material (AAM) with standard SC in their hydration and hardening phase. To monitor the microstructural changes within the two materials SC and AAM, acoustic emission (AE) signals have been recorded for up to ~250 days on 340-liter-cubic specimens. The phenomenon of AE is defined as the emission of elastic waves in materials due to the release of localized internal energy. Such energy release can be caused by the nucleation of micro-fracture, e.g. in concrete while curing or when exposed to load. The occurrence of AE events gives first rough indications of microstructural changes and potentially occurring cracking and thus, provides insights for structural health monitoring (SHM). The results show, that for the first 28 days after casting, less AE activity was detected in the AAM compared to SC. After 61 days, in the AAM material, the number of AE events exceeded those observed in the SC. However, the majority of the AE detected in AAM was related to surface effects, and not to microstructural changes within the matrix. Additionally, the source location analysis indicated, that despite lower activity in SC, we observed some clustering of the events. In contrast, in AAM, the activity inside the specimen is randomly distributed over the whole volume. The monitoring results help to estimate the material’s sealing properties which are crucial to assess their applicability as sealing material for engineered barriers.

• Book : 29(7)
• Pub. Date : 2024
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Background: Metastasis is the most common cause of death in breast cancer and nodal metastasis is one of the most important predictive factors for distance metastasis. One of the intrinsic properties of cancer cells is that they resemble stem cells which are capable of self-renewal, resistance to chemotherapy and radiation, and metastasis. CD90 is a stem cell marker found in several malignancies, including breast carcinoma. The objective of this study was to prove that CD90 can predict the occurrence of axillary nodal metastasis in breast carcinoma. Methods: The study design was a case-control study. The subjects of this study were breast cancer patients at Prof. Dr. I. G. N. G. Ngoerah Hospital who underwent mastectomy and axillary lymphadenectomy in the year 2019. CD90 immunohistochemistry was performed and its association with metastasis, along with various clinicopathological markers, was assessed with chi-square and logistic regression tests with a significance level determined at α=0.05. Results: There were 25 cases of breast carcinoma with axillary nodal metastasis and 25 cases without metastasis. There was a significant relationship between high CD90 expression and the occurrence of nodal metastasis (p=0.010). There was no relationship between patient age, histologic grade, histologic subtype, molecular subtype, and T-stage with axillary nodal metastasis. Breast carcinoma patients with high CD90 expression have a 7.25 times higher nodal metastasis risk compared to patients with low CD90 expression. Conclusion: High CD90 expression could predict axillary nodal metastasis in breast carcinoma.

• Book : 18(2)
• Pub. Date : 2024
• Page : pp.156-161
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