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Improved Isolation of Ultra-High Genomic Dna Suitable for Third-Generation Sequencing
No full textAlthough a variety of protocols to isolate high-molecular-weight genomic DNA exist, the isolation and preservation of ultra-high-molecular-weight genomic DNA of sufficient quality and length for error-free third-generation sequencing remains challenging. Inspired by the isolation of high-molecular-weight DNA in agarose plugs suitable to be separated by pulsed-field gel electrophoresis, we report the construction of an incubation chamber for DNA isolation. The chamber is flanked by semi-permeable polycarbonate membranes of variable pore size for the selective diffusion of compounds and components, which allows efficient cell lysis and the subsequent isolation of ultra-high-molecular-weight genomic DNA without shearing. The designed experimental approach is simple, but effective in isolating high-quality ultra-long genomic DNA that is suitable for third-generation sequencing by Oxford Nanopore Technology from challenging bacterial samples. We envisage that genomic DNA isolation using the incubation chamber, or variations thereof, will facilitate the regular sequencing of megabasepair-long DNA fragments, with a multitude of applications in microbiology, immunology, oncology, paleontology and forensic science
Papercraft Doppler Radar Measurements Based on Covariance Eigenvalue Spectrum-Assisted Empirical Mode Decomposition
No full textDoppler radar systems encounter challenges due to their high costs, cumbersome designs, and heavy weights, especially in resource-limited environments. As a promising alternative, papercraft Doppler radar has emerged, offering a lightweight, easily deployable and cost-effective solution. However, despite many advantages, papercraft-based radar faces inherent challenges due to the material used, which leads to vulnerability to external stimuli. In this article, a novel method is proposed demonstrating that papercraft Doppler radar can achieve high performance comparable to its aluminum counterparts and perform multitarget detection even in noisy environment with multiple stimuli. For the first time, we integrate a papercraft Doppler radar with the proposed covariance eigenvalue spectrum (CES)-assisted empirical mode decomposition (EMD) method, significantly improving the performance of the papercraft radar system. Single and multitarget detection, exploiting proper intrinsic mode function (IMF) selection, is achieved through the CES algorithm, which distinguishes between the target and unwanted components via proper windowing and weighting of the decomposed radar signal. According to the results, the proposed method significantly enhances multitarget movement detection and outperforms existing methods
Homogeneity Enhancement of Oxide Additives in Boron Carbide by Precipitation Method
No full textThis study elucidates the use of the precipitation method to enhance the uniformity of oxide additives in boron carbide ceramics. Achieving a homogeneous distribution of additives is critical, as higher additive content tends to degrade the mechanical properties of boron carbide. In this research, yttrium and aluminium hydroxide salts were dispersed and incorporated into boron carbide slurry under highly alkaline conditions. The mixture was aged and subsequently calcined to produce metal oxide layers around the boron carbide particles. The additive-to-boron carbide ratio and calcination conditions were systematically varied and the resulting powders were characterized using SEM, EDX and zeta potential analyses. The precipitation method effectively improved additive dispersion, achieving a uniform distribution. Furthermore, samples processed through precipitation exhibited higher densities compared to conventional benchmark samples. © 2025 University of Novi Sad, Faculty of Technology. All rights reserved
Derivation of Soil Hydraulic Properties (SHPS) Using a Physics-Based Inverse Calibration Method and International Soil Moisture Network Database
No full textThis study used extensive soil moisture records to estimate "inverse-calibrated Soil Hydraulic Properties (SHPs)" using a multi-processing technique via high-performance computing clusters. Within this objective, a mass conservative numerical model was developed to solve the one-dimensional Richards Equation incorporating two different soil hydraulic models: the well-known van Genuchten Mualem (VGM) model and the relatively new Fredlund-Xing-Wang (FXW). A multiprocessing version of the Differential Evolution Algorithm (DEA) optimization technique was used for inverse calibration of the soil hydraulic parameters. For FXW, calibration statistics were calculated as means of the KGE' (0.89 f 0.1 and 0.83 f 0.23), R (0.89 f 0.1 and 0.85 f 0.21) and ubRMSE (0.017 f 0.01 and 0.015 f 0.02) for the depths 50 and 100 cm, respectively. For VGM, calibration statistics were found as means of the KGE' (0.87 f 0.11 and 0.78 f 0.22), R (0.90 f 0.08 and 0.86 f 0.17) and ubRMSE (0.019 f 0.01 and 0.017 f 0.01) for the same depths, respectively. The employed methodology had highly promising statistical performance for both FXW and VGM to derive SHPs. A comprehensive validation methodology was used to evaluate the reliability of derived SHPs. Correlation analysis showed that derived SHPs strongly correlated with the soil properties and environmental variables. Further, as a validation procedure, initial investigations were also conducted to explore the spatial transferability of the parameters. Despite the use of basic k-means clustering, the resulting soil hydraulic datasets showed statistical similarity or even improvement to hyper-resolution maps used in the literature. While the simulation model of the methodology has certain assumptions and limitations, this study proves that the ISMN database can be used to derive soil hydraulic properties and transfer these parameters to locations other than the calibration points. This study shows that FXW is a promising hydraulic model for the determination of soil moisture at root zone within the complete moisture range. The methodology can also be readily extended to other established soil moisture monitoring networks and potentially extended versions of "inverse-calibrated SHPs" and trained pedotransfer functions are considered to be valuable tools to estimate soil moisture profiles at the root zone
Experimental Study of Evolution of Breach Resulting From Piping at Upper Part of Earth-Fill Dam
No full textPiping and overtopping are the most important causes of earth-fill dam failure. Such dams may erode under seepage, causing a reduction in the structural strength. The aim of this study was to investigate the temporal evolution of the breach and flow rate from the breach resulting from the piping in earth-fill dams. The experiments were carried out at Hydraulics Laboratory of Civil Engineering Department of İzmir University of Economics. The dam was constructed by using a mixture consisting of 85 % sand and 15 % fine (low plasticity clay). In the first scenario a circular tunnel with a diameter of 2 cm was created along the centreline at 6 cm below the dam crest whereas in the second one it was located at the upper edge. Six cameras at different locations recorded the evolution of the progress of the breach formation. The pump flow rate was measured by magnetic flow meter, and the continuity equation was used to calculate the flow rate values from the breach. The time-varied values of the total breach areas were determined using the Gauss Area formula. The image processing method was also applied in the determination of the breach areas. The time-dependent changes of water depth in the channel were also recorded. The obtained experimental findings are presented and commented, together with the universal dimensionless curves. The failure of the dams occurred mainly because of the head cut erosion developed from downstream to upstream. When breaching started, the orifice flow was converted to open channel flow where breach bottom behaved like a broad crested weir. In the second scenario, the rigid lateral side considerably influenced the flow rate and the development of the breach. The peak flow rate corresponding to the first scenario was found approximately 2.3 times greater than that of the second one. The maximum values of all the breach parameters were reached earlier in the case of the seepage along the centerline. The ratios between the values corresponding to the first and the second scenarios were found as 3.25 and 1.75 for maximum breach areas at downstream and at upstream sides, respectively. These ratios were 2.44 and 1.37 for the average breach widths at downstream and upstream sides, respectively. A very good agreement was found between the area values obtained from Gauss area method and image processing technique, in both scenarios. This fact demonstrated that either of these two approaches can be used to determine the time-dependent breach areas. These experimental findings provide the opportunities for the calibration and validation of the numerical models used in the relevant numerical investigations. This study also offers guidance for the strategies concerning emergency action plans related to the failure of homogeneous earth-fill dams when the piping starts at upper part of the homogeneous earth-fill dams
Correction To: Effect of Mechanical Pre-Treatment on the Recovery Potential of Rare-Earth Elements and Gold From Discarded Hard Disc Drives (journal of Material Cycles and Waste Management, (2025), 27, 1, (257-269), 10.1007/S10163-024-02108-0
No full textIn this article the affiliation details for Mertol Gökelma were incorrectly given as “Department of Environmental Engineering, İzmir Institute of Technology, Izmir 35433, Turkey” and should have been deleted. © The Author(s), under exclusive licence to Springer Nature Japan KK, part of Springer Nature 2024
Optimizing Inhibitor Injection in Geothermal Wells With Electrical Submersible Pump
No full textElectrical submersible pump (ESP) is a reliable artificial lift method to extend productive lifespan of geothermal wells. In the geothermal industry a common practice involves installing ESPs below the well's flashing depth. This placement approach aims to mitigate the risk of mineral precipitation, which can occur when hot geothermal fluids transition to a two-phase state (liquid and vapor) as pressure decreases. Positioning the pump below the flashing depth also prevents pump's underloading and gas cavitation. The inhibitor injection line usually integrated around the ESP string and installed downstream of the ESP motor. However, this standard practice introduces a challenge regarding inhibitor performance. While this placement ensures effective distribution of inhibitors throughout the production flow, the extended travel time from the surface to the point of application at the ESP can diminish inhibitor effectiveness due to continuous exposure to high temperatures throughout the wellbore. This study proposes relocating the inhibitor injection point within the production tubing closer to the flashing depth. This reduces inhibitor travel time from 108 min to 48 min and has the potential to significantly improve inhibitor effectiveness. Consequently, the implementation of capillary tubing is anticipated to yield annual cost savings per wellbore of approximately USD 10,000, coupled with the mitigation of mineral deposits within the studied well equipped with ESP. To evaluate this approach, a wellbore simulation tool and PHREEQC were employed to dynamically model the pressure and temperature profiles alongside the geochemical evolution of the produced fluids in the wellbore. This modeling approach offers significant value by potentially enabling the optimization of inhibitor usage and reducing the length of required inhibitor injection line. © 2024 Elsevier Lt
A Room Temperature Chemical Process for Homogeneous Mixing of Precursor Phases for Low Temperature Tetracalcium Phoshate Preparation
No full textThe aim of this study was to prepare phase pure tetracalcium phosphate (TTCP) from the precursor phase mixtures homogeneous at the nano/microscale level at lower heat treatment temperatures in much shorter dwell times. Two different precursor powder mixtures were prepared by reacting CaCO3 with H3PO4 in ethanol or water. The resultant precursor powder mixtures were heat treated at temperatures in the 1200-1350 degrees C range for 2 and 5 h. Phase structures of the powders were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopy analysis. Scanning electron microscopy (SEM) was used for the investigation of powder particle sizes and morphology. Powders synthesized by the heat treatment of both of the starting powder mixtures prepared in ethanol or water with 2 and 5 h of dwell times at 1350 degrees C were determined to be phase pure TTCP. SEM analysis along with the phase identification showed that the precursor powder prepared in ethanol had micron sized plates formed by aggregation of sub-micron sized thin CaHPO4 plates covering CaCO3 particles. The precursor powder prepared in water contained large aggregates of sub-micron sized CaCO3 particles whose surface was covered by precipitated nano-sized hydroxyapatite. TTCP powders were composed of large irregularly shaped particles formed by sintering of smaller equiaxed grains. Average grain and particles sizes of the TTCP powders synthesized from the precursor powder prepared in ethanol were 3.2-3.9 and 8.1-8.4 mu m, respectively. Average grain and particle sizes of the TTCP powders synthesized from the precursor powder prepared in water however were measured to be 3.3-5.1 and 11.2-11.6 mu m, respectively. The TTCP preparation method presented in this study provides homogeneous and well-mixed precursor powders prepared from cheap and commonly available precursors without milling and decreases the heat treatment time to 2 h at 1350 degrees C
Pressureless Joining of Soda Lime Silicate Glass Using Polysilazane-Derived Silica at Near-Room Temperature
No full textPerhydropolysilazane (PHPS) pre-ceramic polymer was used to join soda lime silicate glass at temperatures below 200 degrees C under pressureless conditions. The results show that: (i) the junction material is largely converted to silica at 100 degrees C and fully converted to glass at 150 degrees C; (ii) the samples treated at room temperature and 100 degrees C show a perfectly dense and clean bond, whereas porosity develops starting from 150 degrees C as a result of the hydrolysis reactions and solvent evaporation; (iii) a maximum tensile bond strength of about 5-6 MPa is obtained after treatments at 100 degrees C. Remarkably, after treatment at 500 degrees C, the junction remains intact. These preliminary findings provide the first successful attempt regarding the use of PHPS as a joining material to produce inorganic and transparent bonds for glass at relatively low temperatures
Data Driven Modeling and Design of Cellulose Acetate-Polysulfone Blend Ultrafiltration Membranes Based on Artificial Neural Networks
No full textThis study aimed to develop and validate an Artificial Neural Networks (ANNs) model for the design and optimization of cellulose acetate-polysulfone blend ultrafiltration membranes, produced via the Non-Solvent Induced Phase Separation method. After some data science applications on a comprehensive dataset obtained from literature studies, the ultimate ANNs model exhibited superior predictive capabilities and effectively captured complex nonlinear relationships in the data. The optimum model configuration with a single hidden layer containing six neurons provided reliable predictions by avoiding overfitting and underfitting risks and significantly reducing error metrics. The model analyzed the effects of input variables on outputs, revealing that different stages of the membrane preparation process had varying impacts on performance metrics. This finding emphasized the importance of systematically optimizing the preparation process to enhance overall membrane performance. The model's predictions showed strong agreement with experimental data, further validating its accuracy. The optimum production conditions identified by the model offered significant improvements in membrane performance. Moreover, the model accelerated the membrane development process by reducing the required number of experimental trials and promoting efficient resource utilization. This approach contributed to both economic and environmental sustainability by reducing production costs and energy consumption. This study highlighted the significant potential of machine learning techniques for future innovations and advancements in this field by enabling precise, efficient, and sustainable membrane design and synthesis. © 2025 Elsevier Ltd