Experimental Procedure Research Articles

Interlaboratory Study Toward Combining Gait Kinematics Data Sets of Long-Distance Runners.

The limited sample size in gait studies has hampered progress in the field. This challenge could be addressed through multicenter studies, thereby leveraging data sets from different laboratories. This study compared 3-dimensional lower-extremity running kinematics between the Biomechanics and Motor Control Laboratory, Federal University of ABC (Brazil), and the Running Injury Clinic, University of Calgary (Canada). Three-dimensional lower-extremity kinematics from 23 male runners were collected from each laboratory using comparable instrumentation and experimental procedures. The 3-dimensional hip, knee, and ankle angles were compared within and between centers using root-mean-square deviation. Two-sample t tests Statistical Parametric Mapping tested the hypothesis that the data from both laboratories were not different. The sagittal plane hip, knee, and ankle angles were similar between laboratories, while notable differences were observed for frontal (hip and ankle) and transverse (hip and knee) plane angles. The average interlaboratory root-mean-square deviation (2.6°) was lower than the intralaboratory root-mean-square deviation (Biomechanics and Motor Control = 4.8°, Running Injury Clinic = 5.6°), with the ankle transverse angle displaying the smallest, and the knee transverse angle displaying the largest variability. This study demonstrates the potential of combining gait kinematics data from different laboratories to increase sample size, but frontal and transverse plane data should be considered with caution.

Cutting Finite Element Simulation of Quenched Steel GCr15 Based on ABAQUS

Background: The substantial cutting force and elevated cutting temperature during the machining of hardened steel GCr15 exacerbate tool wear. Objective: In this study, the influence of cutting parameters on cutting force and cutting temperature in the process of hard-cutting GCr15 was studied, the cutting parameters were optimized, and the cutting force and cutting temperature were predicted. Methods: The cutting simulation model was constructed using ABAQUS software, and the cutting force and cutting temperature were investigated under various cutting parameters through range analysis, variance analysis, and signal-to-noise ratio transformation analysis. Results: The simulation and experimental results demonstrated that the cutting force could be optimized by utilizing cutting speed vc=140 m/min, feed rate f=0.1 mm/r, and cutting depth ap=0.1 mm. Under these conditions, the cutting force in the x-direction was measured as 78.560N, while the cutting force in the y-direction was 32.423N. Moreover, for achieving the optimal cutting temperature, the recommended cutting parameters were cutting speed vc=120 m/min, feed rate f=0.1 mm/r, and cutting depth ap=0.4 mm. Conclusion: Compared to the conventional analytical method, which is burdened with high costs and low efficiency, the patent leverages finite element simulation technology to replicate the hardcutting process and its underlying cutting mechanism. This innovation simplifies the otherwise complex and laborious experimental and measurement procedures. By studying cutting force and cutting temperature, the optimization of cutting parameters can be achieved, thus offering valuable theoretical insights for practical production.

Electrochemical hydrogen storage using SrFe12O19 surface-immobilized polyoxometalate

A tri-nickel substituted Keggin-type polyoxometalate (PMo9Ni3O37) was synthesized and subsequently immobilized on the surface of the M-type strontium hexaferrite (SrFe12O19) via the sol-gel method. The investigation of hydrogen storage capacity for the synthesized PMo9Ni3O37@SrFe12O19 nanocomposite was conducted through electrochemical methodologies employing chronopotentiometry (CP). A conventional three-electrode configuration employing copper foam coated with PMo9Ni3O37@SrFe12O19 served as the working electrode and was examined across a current range of ±1.5 mA. The charge and discharge of the experimental procedure indicated the substantial potential of the PMo9Ni3O37@SrFe12O19 nanocomposite in the hydrogen storage process, which was determined 3125 mAh/g during the discharge phase. The successful synthesis was corroborated thorough FT-IR, UV-vis, XRD, SEM, EDX, and BET surface area analysis techniques by examining the characteristic absorption wavelengths or reflection patterns. The size of the nanoparticles was determined through SEM analysis yielding a diameter of 36.76 nm, and using the Scherrer equation, a diameter of 29.22 nm was obtained.

Lagrangian particle tracking at large Reynolds numbers.

In the study of fluid turbulence, the Lagrangian frame of reference represents the most appropriate methodology for investigating transport and mixing. This necessitates the tracking of particles advected by the flow over space and time at high resolution. In the past, the purely spatial counterpart, the Eulerian frame of reference, has been the subject of extensive investigation utilizing hot wire anemometry that employs Taylor's frozen flow hypotheses. Measurements were reported for Taylor scale Reynolds number Rλ > 104 in atmospheric flows, which represent the highest strength of turbulence observed on Earth. The inherent difficulties in accurately tracking particles in turbulent flows have thus far constrained Lagrangian measurements to Taylor scale Reynolds numbers up to approximately Rλ = 103. This study presents the Lagrangian particle tracking setup in the MaxPlanck Variable Density Turbulence Tunnel (VDTT), where Taylor scale Reynolds numbers between 100 and 6000 can be reached. It provides a comprehensive account of the imaging setup within the pressurized facility, the laser illumination, the particles used, and the particle seeding mechanism employed, as well as a detailed description of the experimental procedure. The suitability of KOBO Cellulobeads D-10 particles as tracers within the VDTT is illustrated. The results demonstrate that there is no significant charge exhibited by the particles and that the impact of their inertia on the results is negligible across a wide range of experimental conditions. Typical data are presented, and the challenges and constraints of the experimental approach are discussed in detail.

Enhanced VCA Storage: A Pilot Study Demonstrating Supercooling in Orthotopic Rodent Hindlimb Transplantation

The field of vascularized composite allograft (VCA) transplantation has seen steady, rapid growth, with new innovations driving the evolution from experimental procedures to more standardized therapies. With this expansion comes challenges with graft allocation, preservation, and postoperative graft rejection. Here, we outline the first example of subzero nonfreezing (SZNF), supercooled storage of a whole rat hindlimb with orthotopic transplantation. Rat hindlimbs were procured, loaded, and supercooled for 48 hours at -4°C (n = 4), after which, they were recovered. The loading and recovery phase were performed using subnormothermic machine perfusion (SNMP) during which viability markers (glucose and oxygen consumption, lactate, and resistance) were tracked. Control limbs underwent static cold storage (SCS). After ex vivo validation, the model was piloted in a transplant model, comparing 48 hours of SZNF (n = 1), 48 hours of SCS (n = 1), and 72 hours of SCS (n = 1), which demonstrated no survival beyond postoperative day 4 in the SCS models, and survival until the end of study (postoperative day [POD] 28) in the SZNF model. This study demonstrates the promise of this model in future studies on long-term VCA preservation.

Effects and Mechanisms of Andrographolide for COVID-19: A Network Pharmacology-Based and Experimentally Validated Study

Objective: This study aimed to elucidate the therapeutic effects and underlying mechanisms of andrographolide against COVID-19 through a network pharmacology approach and experimental validation. Methods: Network pharmacology approaches were employed to elucidate potential targets of andrographolide, investigating their overlap with proteins implicated in SARS-CoV-2 infection. The identified targets underwent further analysis through protein-protein interaction (PPI) mapping, gene ontology (GO) categorization, and pathway enrichment within the framework of the Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequent molecular docking studies provided insights into the binding dynamics between andrographolide and the relevant protein targets. To validate these findings, a series of experimental procedures were conducted, including cytotoxicity assays, quantitative PCR analyses, and the deployment of a SARS-CoV-2 pseudovirus system, using BEAS-2B lung epithelial cells as a model. Results: Bioinformatics analysis revealed that andrographolide potentially modulates proinflammatory cytokines, JAK-STAT signaling, and antiviral immunity pathways in COVID-19. Molecular docking showed favorable binding interactions between andrographolide and its putative targets. In vitro studies confirmed that andrographolide suppressed the mRNA expression of IL-6, TNF-α, IL-1β, and STAT3 and inhibited pseudovirus entry and infection at pharmacologically relevant concentrations. Conclusion: The findings suggest that andrographolide could be a promising candidate for the treatment of COVID-19 due to its capacity to both inhibit SARS-CoV-2 and modulate harmful inflammation. Our findings highlight the potential therapeutic value of andrographolide in treating COVID-19, warranting further exploration in clinical trials.

Response surface methodology and process optimization of spark plasma sintered parameters of Ti20Al20Cr5Nb5Ni19Cu12Co19 high entropy alloy

Study was carried out on the effect of milling and sintering process parameters on the relative density and microhardness property of a septenary non-equiatomic Ti20Al20Cr5Nb5Ni19Cu12Co19 high entropy alloy fabricated via spark plasma sintering (SPS) process at 100 °C/min constant heating rate, 5 min dwell time, and at a pressure of 50 MPa. A predictive model was developed through response surface methodology (RSM) using the SPS sintering temperature (ST) and milling time (MT) as the process variables. In order to reduce the number of experimental runs, the design of experiment (DOE) technique was used, to eventually avoid the trial-and-error process associated with conventional experimental procedures. The user-defined design (UDD) of the RSM was used to forecast the optimal operating parameters, and the outcome was validated by experiments. Findings indicate that MT and ST are important in achieving high densification, which leads to high densification and mechanical properties. Optimization model shows that, at MT of 7.20115 h and ST of 899.742 °C, desirable responses of 99.9 % relative density, percentage porosity of 0.0999994 % and a micro-hardness value of 835.21 HV can be attained.

Expeditious and selective synthesis of 2,4,5-trialkyl-1H-imdazoles and benzimidazoles via multicomponent one-pot reaction catalyzed by Schiff base dioxomolybdenum(VI) complex

Imidazoles and benzimidazoles are privileged heterocyclic compounds that can be extensively found in medicinal and materials chemistry, however, the experimental procedures for their synthesis are limited to multicomponent condensation reactions and normally are strongly dependent upon the desired substitution pattern, consequently several procedures with different conditions and catalysts are available in literature. Accordingly, the development of synthetic methodologies to afford these compounds remains a very attractive research problem. In this regard, dioxomolybdenum based catalysts are emerging as versatile and non-expensive reagents for a myriad of chemically relevant transformations. Within this context, an expedient and efficient synthesis of 2,4,5-trialkyl-1H-imidazoles and benzimidazoles from a multicomponent one-pot condensation has been developed with a tridentate Schiff base dioxomolybdenum(VI) complex, resulting in an efficient, simple and readily available catalyst to promote the aforementioned reaction. This reaction offers advantages such as good to excellent yields, good selectivity of products, low catalyst loadings and simple reaction work-up.

A pulsed power facility for studying the warm dense matter regime.

A pulsed power facility has been designed for studying the warm dense matter regime. It is based on the pulsed Joule heating technique, originally proposed by Korobenko and Rakhel [Int. J. Thermophy. 20, 1257 (1999)], where a 3.96µF capacitor bench is used for inducing a solid to plasma phase transition to metallic foils confined into a sapphire cell. The first experiments have been conducted on pure aluminum. Experimental data have been collected using electrical and optical diagnostics. Direct measurements of tension, current, pressure, and particle velocity allow us to evaluate the equation of state (EOS) and the DC conductivity of expanded aluminum. The results are compared to hydrodynamic simulations performed with various EOS models. As a result, collected data on aluminum highlight the relevance of our experimental procedure for improving EOS modeling in the warm dense matter regime.

Theoretical modeling of feedstock-laser energy interaction in directed energy deposition with simultaneous wire and powder feeding

The Laser-based Directed Energy Deposition (L-DED) process is widely employed for the fabrication of numerous metallic parts. It also stands out as a crucial additive manufacturing (AM) technique for creating metal matrix composites (MMCs) reinforced with ceramic particles. The simultaneous deposition of wire and powder feedstocks into the created melt pools on the substrate surface proves advantageous in overcoming the limitations associated with mixed powders in powder deposition alone. The strategy of coaxial wire and powder deposition (CWP-DED) allows for more efficient construction of MMCs with complex geometries and desirable properties. Nevertheless, CWP-DED is a complex multi-phase deposition process that involves highly dynamic interactions among laser beams, wire, and powder particles, influencing laser energy distribution and absorption during the process. This work aims to develop a theoretical model to advance the fundamental understanding of the absorbed and lost laser beam energy by the fed wire and powders in CWP-DED before entering the melt pool. Laser energy absorption coefficients can be calculated based on the Step Wise Heating method to determine the final temperature of the powder particles and wire before entering the melt pool. The experimental validation of the proposed model requires a power meter that fits the CWP-DED system with six inclined laser beams, which is not commercially available so far, to measure the actual output power with and without wire and powder feeding. Consequently, this work presents a detailed explanation of the experimental procedure desired to measure the absorption coefficients of the wire and powder feedstocks and how to validate the proposed model as a future research endeavor. This model plays a vital role in predicting and understanding the amount of heat transferred into the melt pool, which lays a foundation for understanding the complicated melt pool thermodynamics that directly govern the microscopic characteristics and macroscopic properties of the as-built parts.

Recombinant Influenza A Viruses Expressing Reporter Genes from the Viral NS Segment.

Studying influenza A viruses (IAVs) requires secondary experimental procedures to detect the presence of the virus in infected cells or animals. The ability to generate recombinant (r)IAV using reverse genetics techniques has allowed investigators to generate viruses expressing foreign genes, including fluorescent and luciferase proteins. These rIAVs expressing reporter genes have allowed for easily tracking viral infections in cultured cells and animal models of infection without the need for secondary approaches, representing an excellent option to study different aspects in the biology of IAV where expression of reporter genes can be used as a readout of viral replication and spread. Likewise, these reporter-expressing rIAVs provide an excellent opportunity for the rapid identification and characterization of prophylactic and/or therapeutic approaches. To date, rIAV expressing reporter genes from different viral segments have been described in the literature. Among those, rIAV expressing reporter genes from the viral NS segment have been shown to represent an excellent option to track IAV infection in vitro and in vivo, eliminating the need for secondary approaches to identify the presence of the virus. Here, we summarize the status on rIAV expressing traceable reporter genes from the viral NS segment and their applications for in vitro and in vivo influenza research.

Estimation of CZM Parameters for Investigating the Interface Fracture of Adhesively Bonded Joints Under Mode I, Mode II, and Mixed‐Mode (I/II) Loading

ABSTRACTThe mechanical performance of joints for any engineering applications requires accurate characterization of joint interfaces. This paper presents a simplified experimental procedure to estimate the cohesive zone model (CZM) parameters for predicting the interface failure of adhesively bonded joints subjected to mode I (opening) and mode II (shear) loading. The novelty of this procedure lies in predicting all CZM parameters—cohesive stiffness, strength, and cohesive energy (fracture toughness), of the bonded interface using one common experimental setup. It is observed that the cohesive strength and cohesive energy in shear loading are approximately 3.8 and 11.6 times, respectively, compared to the opening loading condition. Employing a triangular cohesive law, the CZM parameters are combined with appropriate damage initiation (quadratic stress) and evolution (power law) criteria. The proposed methodology is verified against experimental load–displacement responses of the bonded interface under mixed‐mode I/II (opening/shear) loading across a wide range of mode mixity (α = 0°, 15°, 30°, 45°, 60°, 75°, and 90°). The maximum error between the experimental and the numerical peak load is 5.11%. The acceptable agreement between the numerical and experimental results confirms the effectiveness of this method in investigating interface fracture in adhesively bonded joints under different loading conditions.

Influence of Continuous Rotation and Optimal Torque Reverse Kinematics on the Cyclic Fatigue Strength of Endodontic NiTi Clockwise Cutting Rotary Instruments.

Objectives: The objective of the present study was to evaluate the cyclic fatigue strength of clockwise cutting rotary endodontic instruments when subjected to two different kinematics: continuous clockwise rotation and clockwise reciprocation movement under optimum torque reverse (OTR) motion. Methods: New ProTaper Next X1 (n = 20) and X2 (n = 20) instruments were randomly divided into two subgroups (n = 10) based on kinematics (continuous rotation or OTR). The specimens were tested using a custom-made device with a non-tapered stainless-steel artificial canal measuring 19 mm in length, featuring a 6 mm radius and an 86-degree curvature. All instruments were tested with a lubricant at room temperature until a fracture occurred. The time to fracture and the length of the separated fragment were recorded. Subsequently, the fractured instruments were inspected under a scanning electron microscope for signs of cyclic fatigue failure, plastic deformation, and/or crack propagation. The subgroup comparisons for time to fracture and instrument length were performed using the independent samples t-test, with the level of statistical significance set at 0.05. Results: When using OTR movement, the ProTaper Next X1 increased the time to fracture from 52.9 to 125.8 s (p < 0.001), while the ProTaper Next X2 increased from 45.4 to 66.0 s (p < 0.001). No subgroup exhibited plastic deformations, but both showed dimpling marks indicative of cyclic fatigue as the primary mode of failure. Additionally, OTR movement resulted in more metal alloy microcracks. Conclusions: The use of OTR motion extended the lifespan of the tested instruments and resulted in a higher number of metal microcracks. This suggests that OTR motion helped to distribute the mechanical stress more evenly across the instrument, thereby relieving localized tension. As a result, it delayed the formation of a single catastrophic crack, enhancing the overall performance of the instruments during the experimental procedures.

Modelling and Experimental Validation of the Flame Temperature Profile in Atmospheric Plasma Coating Processes on the Substrate

This work presents a characterisation model for the temperature distribution at different substrate depths during the atmospheric plasma spray (APS) coating process. The torch heat flow in this model is simulated as forced convection defined by a surface, a temperature profile, and a convection coefficient. The simulation model considers three plasma temperature profiles of the Al2O3 coating on a 5 mm thickness flat aluminium substrate. The simple and low-cost experimental procedure, based on a thermocouple, measures the plasma plume temperature distribution of the APS coating system, and their results are used to obtain the parameter values of each of the three proposed plasma temperature profiles. The experimental method for in situ non-contact temperature measurements inside the substrate is based on an infrared pyrometry technique and validates the simulation results. The Gaussian temperature profile shows excellent accuracy with the measured temperatures. The Gaussian approach could be a powerful tool for predicting residual stress through a coupled one-way thermal-mechanical analysis of the APS process.

Optically driven ultraviolet-C glowing from an in situ trapping-detrapping approach.

In recent years, the world has witnessed rapid progress in research on ultraviolet luminescent materials, ranging from high-level anticounterfeiting and solar-blind optical tagging to antibacterial applications. In particular, a background-signal free solar-blind surveillance of ultraviolet-C photons provides an opportunity in bright indoor and outdoor environments. However, ambient daylight or inevitable external photostimulation is always eliminated or underestimated in the research of persistent phosphors. Herein, an in situ trapping-detrapping experimental procedure is employed to reveal more information on the total trap energy and trap modulations after photostimulation. Our findings reveal the presence of optically active trapping defects with photostimulated detrapping and retrapping behavior. This work provides a fundamental advance in revealing the trap distribution and trap reshuffling during glowing-in-the-daylight events, offering what we believe to be new insights into manipulating traps.

Water as a Reactant: DABCO-Catalyzed Hydration of Activated Alkynes for the Synthesis of Divinyl Ethers.

A practical and efficient addition of water to readily available activated alkynes delivering divinyl ethers is reported. The reaction proceeds with full atom economy in a very straightforward experimental procedure. Additionally, of all the tertiary amines studied to catalyze the reaction, the best and most efficient is clearly DABCO (1,4-diazabicyclo[2.2.2]octane). Finally, the solvent choice is crucial for the efficiency of this process and we have found that the reaction is best performed in wet dichloromethane for propiolic esters and alkynones, and in wet acetonitrile for propiolamides.

Enhanced Hydrophobicity and Oleophilicity of Modified Activated Carbons Derived from Agro-Wastes Biomass for the Removal of Crude Oil from Aqueous Medium

Crude oil spillage has tremendous environmental impacts and poses severe pollution problems worldwide due to the continuous activities and operations in the oil and gas sector. This has resulted in the urgent need for clean-up techniques such as the use of natural adsorbents which is considered a relatively low-cost, readily-available, efficient, eco-friendly, and easy-to-deploy mode of addressing oil spillage due to its high oil sorption capacity/efficiency, high oil selectivity, oleophilic, enduring, reusability and biodegradable properties. Empty palm fruit bunch and coconut coir were used as precursors to produce activated carbons for oil spill remediation. The influence of varying parameters was investigated using a batch experimental procedure resulting in the crude oil adsorption capacity increasing with a corresponding increase in contact time, initial oil concentration, temperature, agitation speed, and particle size but decreasing in adsorbent dosage. The combination of surface morphological modification and hydrophobicity enhancement resulted in significantly improved adsorption capacity for crude oil removal (2710.0 mg/g and 4859.5 mg/g for EPFBAC&amp;lt;SUB&amp;gt;LA&amp;lt;/SUB&amp;gt; and CCAC&amp;lt;SUB&amp;gt;L.A&amp;lt;/SUB&amp;gt; respectively), as evidenced by both FTIR and SEM analyses. The experimental isotherm data were analysed using various isotherm models and the best-fitted isotherm model was the Freundlich model with a correlation coefficient (R&amp;lt;sup&amp;gt;2 &amp;lt;/sup&amp;gt;= 0.991 and R&amp;lt;sup&amp;gt;2 &amp;lt;/sup&amp;gt;= 0.999) for EPFB&amp;lt;SUB&amp;gt;L.A&amp;lt;/SUB&amp;gt; and CCAC&amp;lt;SUB&amp;gt;L.A&amp;lt;/SUB&amp;gt; respectively. The kinetic behaviour of the adsorption process was best described by pseudo-second order with R&amp;lt;sup&amp;gt;2&amp;lt;/sup&amp;gt; values of 0.970 and 0.999 for EPFBAC&amp;lt;SUB&amp;gt;LA&amp;lt;/SUB&amp;gt; and CCAC&amp;lt;SUB&amp;gt;L.A&amp;lt;/SUB&amp;gt; respectively while Boyd model revealed that the adsorption was controlled by an internal transport mechanism and film diffusion was the rate-limiting step. The crude oil adsorption was chemisorption and endothermic owing to the positive enthalpy values (ΔH&amp;lt;sup&amp;gt;o&amp;lt;/sup&amp;gt; = 183.890 KJ/mol for EPFBAC&amp;lt;SUB&amp;gt;L.A &amp;lt;/SUB&amp;gt;and ΔH&amp;lt;sup&amp;gt;o&amp;lt;/sup&amp;gt; = 69.656 KJ/mol for CCAC&amp;lt;SUB&amp;gt;L.A&amp;lt;/SUB&amp;gt;), the positive value of entropy suggested that the adsorption process was accompanied by an increase in the degree of randomness or disorder at the interface between the adsorbent and the adsorbate. A temperature rise led to a decline in Gibbs energy (ΔG&amp;lt;sup&amp;gt;o&amp;lt;/sup&amp;gt;), suggesting that adsorption became more feasible and spontaneous at higher temperatures and the significant activation energies indicated the existence of a substantial energy barrier that must be overcome to initiate the reaction. The results showed the significant capability of the prepared adsorbents to be used as a low-cost, re-generable and eco-friendly adsorbent in oil spill clean-up and is recommended to exploit its usage on a large scale.

Ovarian tissue cryopreservation and transplantation as a natural means to delay menopause.

Ovarian tissue cryopreservation and transplantation (OTCT) offers hope for preserving fertility and endocrine functions in patients undergoing gonadotoxic treatments. Advancements in techniques for the procedure have transformed OTCT from an experimental procedure into a viable option. There is a growing interest in utilizing OTCT to delay menopause and alleviate associated health issues. Menopausal transition affects women globally, leading to symptoms and long- term health risks. OTCT has the potential to restore endocrine functions, reducing menopause-related symptoms while mitigating health consequences such as osteoporosis and cardiovascular diseases. Although the use of OTCT for delaying menopause is not clinically proven, the discussion around shows potential for future utilization. In essence, the remarkable advancements in OTCT have bestowed upon us the ability to safeguard fertility and sustain the delicate endocrine functions of the ovaries. However, it is the tantalizing prospect of utilizing this technique to postpone menopause and alleviate its associated symptoms that truly captivates the imagination. Further research is imperative to substantiate the clinical efficacy of OTCT; nonetheless, its potential in menopausal therapy is both promising and warrants comprehensive exploration. This review highlights advancements and the feasibility of OTCT to postpone menopause as an alternative approach to currently used conventional menopause therapy methods.

Experimental study on the parameters affecting the performance of spiral tube pump

This experimental study delves into the critical parameters influencing the performance of spiral tube pumps—a centuries-old technology attributed to H.A. Wirtz in 1746. The Spiral Tube Pump system, constructed using a transparent flexible tube wound spirally on a waterwheel, harnesses the kinetic energy of a river, offering a simple, cost-effective, and emission-free irrigation solution using locally available materials. Operating on the principles of a manometer, water and air plugs are pushed into the pipe alternately by the pump. Key factors crucial to enhancing the performance of this technology are investigated, focusing on submergence ratio, rotational speed, outer diameter, and the number of turns of the spiral tube. The experimental setup involves a prototype featuring a 4-meter-long, ¾-inch diameter transparent flexible tube spirally wound on a 1.5-meter-wide water wheel, achieving a maximum output of approximately 30 L per minute discharge and a 3.3-meter head. Through a series of rigorous experimental procedures, it becomes evident that wheel speed and submergence ratio significantly impact the pump’s discharge. For 600% increase in wheel speed, up to about 500% discharge increase was observed. Also for 300% increase in submergence ratio, up to about 275% increase in discharge was observed. The number of spiral turns predominantly influences the pump’s head. For 100% increase in spiral turn, up to about 33% increment in head was observed. And the outer diameter affects both discharge and head. For 87% increase in outer diameter, up to about 80% of increase in discharge and up to about 163% increase in head was observed. These findings underscore the adaptability of the Spiral Tube Pump design to specific irrigation field conditions. For instance, in scenarios where the irrigation field is elevated relative to the river, incorporating a greater number of spiral tube turns can enhance the pump’s efficiency in transporting water to the desired location.

The Allium cepa comet assay for environmental sample assessment: a scoping review.

The purposes of this review were to investigate the application of the comet assay in Allium cepa root cells to assess the genotoxicity of environmental samples and to analyse the experimental procedures employed. A literature search was performed selecting articles published between January 2000 and October 2023 from online databases using the combined search terms 'comet assay' and 'A. cepa'. Only 18 papers met the inclusion criteria. None of these were published in the first eight years (2000-2007), highlighting the increasing interest in using the comet assay on A. cepa to analyse environmental samples over the last decade. The majority of the selected studies (15/18, 83%) were performed on samples belonging to the water compartment on onion bulbs. Half of the selected studies (9/18) were conducted to demonstrate the DNA damaging effect of the sample, while the other half of the studies not only recognized the presence of genotoxic agents but also addressed possible remediation measures. Detailed analysis of the experimental procedures revealed heterogeneity in many key steps, such as exposure time, test controls, nuclei isolation solutions, duration of electrophoresis, and number of nuclei scored. This literature review has shown that the comet assay on A. cepa, although recognized as an appropriate tool, is underutilized in environmental toxicology. Greater standardization could lead to its more widespread use, providing valuable information on the genotoxicity of environmental samples and the ability of different processes to mitigate their negative effects on plants.