Mesh Type Research Articles

Attempt to re-estimate organ doses of victims in non-homogeneous exposure accident by means of the state-of-the-art Mesh-type Reference Computational Phantom-a case study of an IR-192 source accident.

An attempt was made to estimate organ doses of a victim in a high-dose non-homogeneous exposure accident caused by a sealed 192Ir gamma-ray source. The Gilan accident was selected as a case study. Organ doses including testis, red bone marrow and so on were properly estimated by applying the Monte Carlo calculation with the state-of-the-art adult male Mesh type Reference Computational Phantom. By introducing a complicated exposure scenario, the dose distribution on the right chest of the victim in the Gilan accident could be reproduced to a certain extent.

Mesh-associated complications in minimally invasive ventral mesh rectopexy: a systematic review.

Ventral mesh rectopexy (laparoscopic and robotic) is a common and well established treatment of rectal prolapse. Although described as safe and effective, complications, especially mesh-associated ones are often mentioned. Additionally, there is no consensus regarding the mesh type and fixation method as well as the materials used for this purpose. The aim of this systematic review was to identify the total amount of complications and of those the mesh-associated ones. Pubmed, Web of Science and Cochrane Central Register were screened for complications in general and in detail regarding the mesh(es) and a systematic review was performed. Following qualitative evaluation, 40 studies were identified for further investigation. Across 6269 patients, complications were found in 9.2% (622 patients). Mesh-related complications were described in 1.4% (88 patients) of which 64.8% were erosions, 11.4% fistulas and 13.6% mesh releases. The complication rate according to the different materials were low with 1% in biological and synthetic meshes and 1.8% in not further described or mixed mesh type. Non-absorbable material to fixate the mesh was most frequently used to fixate the mesh. Laparoscopic ventral mesh rectopexy is a safe operation with a low-complication rate, regardless of mesh type.

Mesh-associated pain syndrome: predictors for continence and prolapse mesh removal surgery in a single centre

ObjectiveOver the last two decades one of the main surgical treatment for stress urinary incontinence (SUI) and pelvic organ prolapse (POP) surgery was the insertion of non-absorbable mesh to restore continence and prolapse respectively. Over time complications arose including mesh-associated pain syndrome (MAPS), mesh exposure, mesh, erosion, chronic bladder/vaginal infections, and dyspareunia. Consequently, women chose surgical mesh removal to counter these problems. However, little is known about the demographics, medical co-morbidities, mesh types involved and the timing from mesh insertion to mesh removal. This retrospective study will look at which of these factors may be closely associated with mesh removal surgery.DesignRetrospective evaluation.SettingFemale Pelvic Medicine and Reconstructive Surgery (FPMRS) Clinic at University College London Hospitals NHS Foundation Trust.PopulationAll patients presenting to the FPMRS Clinic between June 2011 to December 2019, requesting mesh removal surgery with a history of MAPS and other mesh complications were included in this study.MethodsPatient demographics including age, ethnicity, obstetric history, and medical co-morbidities; type of mesh/anatomical route used; onset of symptoms; and time from insertion to removal were recorded.Main Outcome MeasuresDetermination of correlation coefficients between patient demographics, patient reported symptoms and mesh removal surgery.ResultsThree hundred and forty-five women with a history of MAPS were included in the study. Women in the 40–60 year old cohort accounted for 54.4% of mesh removal surgery; 54.8% had a BMI under 30 and almost 90% were Caucasian. 96.5% had had children, with over 77% having had a vaginal delivery. 91.9% of patients reported other health conditions including 18.8% with a concomitant history of mental health problems and 15.4% with a history of heart disease. Over 80% of women undergoing mesh removal surgery had a continence mesh (49% retropubic and 32% obturator continence mesh) removed, whereas 20% had an abdominal prolapse and/or vaginal prolapse mesh removed. The average time from mesh insertion to mesh removal was seven years, with the prevalence of mesh removal surgery averaging 85% (range 50–100%) depending on the comorbidity determined.ConclusionsAll women presented to the clinic with a history of MAPS and other comorbidities which may have influenced their decision to pursue mesh removal surgery. There were no specific predictors, other than chronic pain associated with mesh, determining which women underwent surgery, though those with continence mesh were more likely to do so.

Piecewise flat Ricci flow of compact without boundary three-manifolds

Using a recently developed piecewise flat method, numerical evolutions of the Ricci flow are computed for a number of manifolds, using a number of different mesh types, and shown to converge to the expected smooth behavior as the mesh resolution is increased. The manifolds were chosen to have varying degrees of homogeneity, and include Nil and Gowdy manifolds, a three-torus initially embedded in Euclidean four-space, and a perturbation of a flat three-torus. The piecewise flat Ricci flow of the first two are shown to converge to known smooth Ricci flow solutions, with the remaining two flowing asymptotically to flat metrics.

Experimental Study of Stack Porosity on the Performance of Thermoacoustic Refrigerator with Unparalleled Wire Mesh Stacks

The effect of stack porosity on thermoacoustic refrigerator performance with different wire mesh stack designs is investigated experimentally in this paper. Thermoacoustic refrigeration is an innovative technique that employs the principles of thermodynamics and acoustics to achieve cooling effects without the need for hazardous refrigerants or mechanical components. Regardless of their potential, the wire mesh stacks' density and porosity are crucial characteristics that significantly impact the system's performance. The influence of three different types of wire mesh on the performance of thermoacoustic refrigerators was investigated in this study. The meshes used were #14, #16, and #18. The hydraulic radius, porosity, and clear opening differed for each variant. To determine which wire mesh structure was most effective in cooling, we tracked the changes in temperature in both the hot and cold heat exchangers. Based on the experimental results, it was observed that wire mesh #18 had a porosity of 72.6% and a hydraulic radius of 0.211 mm. This wire mesh demonstrated the most notable temperature reduction, decreasing by 4.8 °C and reaching a minimum temperature of 22.3 °C in the prototype model. The results indicate that thermoacoustic refrigerators can be improved with a larger porosity layout, leading to more noticeable temperature differences across the stack and better cooling efficiency. Findings from this study highlight the importance of optimizing parameters and designing stacks for sophisticated thermoacoustic refrigerator systems. These findings highlight the possible advantages of thermoacoustic refrigerators that use stacks of high-porosity wire mesh and give direction for future design considerations.

An energy stable high-order cut cell discontinuous Galerkin method with state redistribution for wave propagation

Cut meshes are a type of mesh that is formed by allowing embedded boundaries to “cut” a simple underlying mesh resulting in a hybrid mesh of cut and standard elements. While cut meshes can allow complex boundaries to be represented well regardless of the mesh resolution, their arbitrarily shaped and sized cut elements can present issues such as the small cell problem, where small cut elements can result in a severely restricted CFL condition. State redistribution, a technique developed by Berger and Giuliani in [1], can be used to address the small cell problem. In this work, we pair state redistribution with a high-order discontinuous Galerkin scheme that is L2 energy stable under arbitrary quadrature. We prove that state redistribution can be added to a provably L2 energy stable discontinuous Galerkin method on a cut mesh without damaging the scheme's L2 stability. We numerically verify the high order accuracy and stability of our scheme on two-dimensional wave propagation problems.

CFD Simulation of Stirling Engines: A Review

Stirling engines (SEs) have long attracted the attention of renewable energy researchers due to their external combustion design and flexibility in operating with various heat sources. The mathematical analysis of these devices is conducted by using a broad range of models ranging from basic zero-order to highly detailed fourth-order models, which are implemented through Computational Fluid Dynamics (CFD) simulations. The unique features of this last approach, combined with the increase in computing power, have promoted the use of CFD as a tool for analyzing SEs in recent years, significantly reducing the costs associated with prototype construction. However, Stirling CFD simulations are sophisticated due to the variety of physical phenomena involved, such as volume change, conjugated heat transfer, turbulent compressible fluid dynamics, and flow through porous media in the regenerator. Furthermore, there is currently no comprehensive review of CFD simulations of SEs in the literature; therefore, this contribution aims to fill that gap. Emphasis has been placed on identifying the type of engine, the physical phenomena modeled, the simplifying assumptions, and specific numerical aspects, such as mesh type, spatial and temporal discretization, and the order of the numerical schemes used. As a result, it has been found that in many cases, CFD numerical reports lack sufficient detail to ensure the reproducibility of the simulations. This work proposes guidelines for reporting CFD studies on Stirling engines to address this issue. Additionally, the need for a sufficiently detailed experimental benchmark database to validate future CFD studies is stressed. Finally, the use of Large Eddy Simulations on coupled key engine components—such as compression and expansion spaces, pistons, displacer, and regenerator—is suggested to provide further insights into the specific flow and heat transfer characteristics in Stirling engines.

Experimental and numerical investigation on RC beams with web openings subjected to pure torsion strengthened by ferrocement technique or GFRP sheets

The main objective of the current experimental and numerical study is to investigate the effect of strengthening by ferrocement layers on the behavior of reinforced concrete (RC) beams with openings subjected to pure torsion and compare it with the beams that were strengthened by Glass Fiber Reinforced Polymer (GFRP). The experimental investigation consists of twelve reinforced concrete (RC) beams that have been divided into four groups. The parameters under investigation included the strengthening technique (ferrocement or External Bonded Glass Fiber Reinforced Polymer EB-GFRP), type of steel mesh (welded wire mesh and expanded metal mesh), number of layers of mesh (1, 2, 3), extension length outside opening (50, 100 or 200) mm, strengthening configuration (full or U-shape) wrapping, and the anchoring system effect. The experimental work consists of one solid beam and eleven beams with openings. The tested beams yielded results such as cracking and ultimate torques, angle of rotation, and mechanism of failure. Creating an opening in the control solid beam resulted in a 38.46 % decrease in ultimate torque, while using different techniques during this research proved efficiency in the strengthening process. Using GFRP U-wrapping and fully wrapping to strengthen the area around the beam's opening increased the ultimate torque by 50 % and 81.25 %, respectively, compared to the un-strengthened beam with an opening. Adding fully wrapped ferrocement layers to the beam with an opening greatly improved its torsional strength. The ultimate torque increased by 40.63 % to 81.25 % compared to the beam with an unreinforced opening. Increasing the number of welded steel mesh layers from 1 to 3 in the ferrocement strengthening technique led to an increase in ultimate torque from 40.63 % to 75 % compared with the un-strengthened beam with the opening. The tests showed that using expanded metal mesh instead of welded wire mesh in strengthened beams with holes led to a 9.43 % higher ultimate torsional capacity, indicating that the expanded metal mesh worked better than the welded wire mesh. Using the U-shape ferrocement wrapping with anchors was better than without anchors, resulting in a 9.1 % increase in the ultimate torsional capacity. Applying a fully wrapped GFRP sheet or expanded metal mesh ferrocement strengthening achieved the highest ultimate torque, 81.25 % more than the un-strengthened beam with an opening. Moreover, a 3D non-linear finite element analysis is conducted using ABAQUS software to forecast the torsional properties of beams strengthened by either ferrocement or EB-GFRP. The numerical model captured the failure patterns, twisting angle, and ultimate load of tested beams. The experimental and analytical results were in good agreement. The research concluded the effectiveness of using the ferrocement reinforced with different steel mesh types in strengthening reinforced concrete beams with openings under pure torsion, the cost-efficiency and simplicity of ferrocement as a solution compared to its results with EB-GFRP techniques.

Bone augmentation using bioresorbable mesh domes containing bone graft granules

Bone graft granules are valuable tools for ridge area bone grafting owing to their ease of manipulation and interconnected porous structure. Guided bone regeneration (GBR) using barrier membranes is commonly used for alveolar ridge augmentation; however, the surgical procedures are technically complicated. In this study, we fabricated bioresorbable mesh domes (BMDs) using two types of Vicryl mesh (woven and knitted types) containing carbonate apatite granules. BMD samples were prepared in three groups: upper sides made from the woven type (UW) and lower sides made from the woven type (LW) (the UW/LW group), upper sides made from the woven type (UW) and lower sides made from the knitted type (LK) (the UW/LK group), and upper sides made from the knitted type (UK) and lower sides made from the knitted type (LK) (the UK/LK group). The samples were subsequently implanted into rabbit calvaria, and radiomorphometric and histological analyses were conducted. The UK/LK group exhibited enhanced appositional bone formation because the knitted mesh on the skin side prevented the infiltration of a substantial amount of fibrous tissue. This increase in bone formation could be attributed to the interaction between granules and osteoprogenitors that pass through the mesh from the host bone. Conversely, the UW/LW and UW/LK groups presented limited appositional bone formation. Compared with knitted mesh, woven mesh might tend to be absorbed over a short span, allowing fibrous tissue invasion and inhibiting new bone formation. Additionally, BMDs could retain granules in a targeted location and avoid displacement of the granules to unintended locations.Graphical

A Comparison of Free and Mapped Meshes for Static Structural Analysis

Abstract This study addresses the challenge faced by Finite Element Analysts when choosing between free and mapped meshes, especially in terms of convergence stability and solution accuracy. The investigation focuses on 3D solid models under static structural loading, analyzed using Ansys® and MSC Patran®. Both free and mapped mesh types, employing equivalent 3D solid elements, are used to assess an aircraft structural component under design load conditions, with fixed boundaries. For free meshes, Tet10 elements in Patran (equivalent to Solid 72 in Ansys) are used, whereas for mapped meshes, CPENTA / CHEXA elements in Patran (equivalent to Wed6 / Hex8 in Ansys) are employed. Mesh convergence studies ensure that discretization does not affect the numerical solution. Notably, a significant stress increase is observed with successive refinement of free meshes, while mapped meshes achieve mesh independence at coarser refinement levels. Comparison of fringe plots indicates the same location for maximum deformation and equivalent stress in both free and mapped mesh models. The findings demonstrate that free meshes tend to underpredict maximum deformation and equivalent stress compared to mapped meshes, with both meshes showing deformation and stress at consistent locations. The findings underscore the importance of carefully choosing the appropriate mesh type, particularly when analyzing critical structural components, to ensure reliability and accuracy in FEA simulations.

Comparative Studies on In-Plane Shear Behavior of Masonry Wallettes Retrofitted with Mortar, UHPC, and ECC Ferrocement: Shotcrete and Prefabricated Panels

Masonry walls, prevalent in many historical and contemporary structures, often require retrofitting to meet modern safety and performance standards. Motivated by the need for efficient and reliable retrofitting solutions, this research investigates the potential of various types of ferrocement, reinforced with high-strength steel meshes, to enhance the in-plane shear behavior of brick masonry walls. Through rigorous diagonal compression tests on nine masonry wallettes, the study evaluated the performance of ferrocement overlays in terms of overlay configuration (asymmetric or symmetric), cementitious material type (mortar, ECC, or UHPC), the presence or absence of steel mesh, and construction method (shotcrete or prefabricated panels). The results indicated that UHPC and ECC overlays significantly enhanced post-cracking deformation capacity. Compared to the asymmetric retrofit, the symmetric retrofit led to more uniform deformation in the retrofitted wallette, effectively improving the maximum shear by up to 119 %. While UHPC shotcrete was more effective in improving the shear strength, ECC shotcrete led to the highest rupture shear strain and pseudo-ductility for the retrofitted wallette, reaching 0.83 % and 17.2, respectively. Moreover, although steel mesh inclusion in the ferrocement overlay was crucial in enhancing post-peak ductility, its impact on shear strength of the retrofitted wallettes was minimal. The test results also demonstrated that the developed prefabricated UHPC panels emerged as an effective retrofitting solution to simultaneously improve the strength, deformation capacity, and ductility for masonry wallettes. In addition to the experimental investigation, a new strength model, accounting for various key design variables, was developed, offering reliable shear strength predictions for the retrofitted wallettes.

Study on the predictions of acoustic characteristics of microspeakers based on the specific airflow resistance of ventilation materials: Mesh type

In this study is presented a method for predicting the acoustic characteristics of microspeakers with mesh-type ventilation materials that combines specific airflow resistance with equivalent circuit model. The specific airflow resistances of eight types of ventilation materials were quantified using a self-made measurement system. These materials were then used to simulate the acoustic properties of 40 φ and 20 φ microspeakers, respectively. The results were compared with simulation results obtained using Dr. Maa’s porous plate acoustic impedance and actual measurements. After applying a stable correction factor, the self-made measurement system accurately determined specific airflow resistance values with high reproducibility and stability. A regression curve based on scanning electron microscope obtained porosity and measured specific airflow resistance effectively predicted the specific airflow resistance of materials with known porosity. Applying these values to acoustic simulations, the proposed method significantly improved accuracy, outperforming Dr. Maa’s method by a factor of six, and closely matched actual measurements. This innovative approach is versatile and applicable to various conditions and types of ventilation materials, as well as enhances predictions of their impact on electro-acoustic product performance.

An Update on Open Inguinal Hernia Repair in Adults: Review Article

Open inguinal hernia repairs are a common general surgical procedure, and it can be divided into mesh-based repairs and sutured based repairs. Mesh-based repairs are the most popular open inguinal hernia repair with the Lichtenstein repair being the most common surgical procedure. The sutured based repairs are not as commonly performed with the Shouldice repair being the most popular repair, but the Desarda repair is slowly emerging as a viable sutured based inguinal hernia repair. We have conducted this review article to look at the varies types of mesh based and sutured based repairs for open inguinal hernia repair including their complications and recurrence rate. We also looked at the effect of chronic pain and the role of antibiotic prophylaxis in open inguinal hernia repair.

Computational Modeling Approach to Profile Hemodynamical Behavior in a Healthy Aorta.

Cardiovascular diseases (CVD) remain the leading cause of mortality among older adults. Early detection is critical as the prognosis for advanced-stage CVD is often poor. Consequently, non-invasive diagnostic tools that can assess hemodynamic function, particularly of the aorta, are essential. Computational fluid dynamics (CFD) has emerged as a promising method for simulating cardiovascular dynamics efficiently and cost-effectively, using increasingly accessible computational resources. This study developed a CFD model to assess the aorta geometry using tetrahedral and polyhedral meshes. A healthy aorta was modeled with mesh sizes ranging from 0.2 to 1 mm. Key hemodynamic parameters, including blood pressure waveform, pressure difference, wall shear stress (WSS), and associated wall parameters like relative residence time (RRT), oscillatory shear index (OSI), and endothelial cell activation potential (ECAP) were evaluated. The performance of the CFD simulations, focusing on accuracy and processing time, was assessed to determine clinical viability. The CFD model demonstrated clinically acceptable results, achieving over 95% accuracy while reducing simulation time by up to 54%. The entire simulation process, from image construction to the post-processing of results, was completed in under 120 min. Both mesh types (tetrahedral and polyhedral) provided reliable outputs for hemodynamic analysis. This study provides a novel demonstration of the impact of mesh type in obtaining accurate hemodynamic data, quickly and efficiently, using CFD simulations for non-invasive aortic assessments. The method is particularly beneficial for routine check-ups, offering improved diagnostics for populations with limited healthcare access or higher cardiovascular disease risk.

Elective complex ventral hernia repair in contaminated fields: A propensity score–matched analysis of long-term quality of life and outcomes between different prostheses

BackgroundRandomized studies have endorsed nonabsorbable prosthetics for contaminated ventral hernia surgery, yet the broader applicability and impact on patient-reported outcomes are still questioned. Here, we evaluated the long-term outcomes of elective contaminated ventral hernia repairs (based on Centers of Disease Control and Prevention [CDC] wound classification) using real-world data from a multicenter US cohort, focusing on quality of life and postoperative pain. MethodsThe Abdominal Core Health Quality Collaborative database was queried for patients undergoing elective contaminated (CDC class II–IV) ventral hernia repair (2013–2023). After propensity matching, we compared long-term differences in patient-reported quality of life and pain scores (by HerQLes and PROMIS questionnaires) among those who underwent repair with nonabsorbable, absorbable synthetic, and biologic mesh. ResultsA total of 1,073 patients were included, of whom 920 (86%), 56 (5%), and 97 (9%) underwent repair with nonabsorbable, absorbable synthetic, and biologic mesh, respectively. Among them, the median age was 62 years (interquartile range [IQR] 53–70), and 523 (49%) were male. The median length and width of the defect were 20 cm (IQR 12–25) and 13 cm (IQR 8–16), respectively. A transversus abdominis release was performed in 716 patients (67% of all cases). In most cases, the mesh was positioned in the retro-rectus (85%) and/or the preperitoneal space (45%). Before and after propensity matching (n = 185), the change from baseline in HerQLes and PROMIS scores at 6 months and at 1, 3, 5, and 6 years was comparable between different types of mesh. Lastly, there were no differences in readmission, surgical site infection, or surgical site occurrence at 30 days. Recurrence at 1 year was also comparable among groups. ConclusionIn the long term, there were no differences in quality of life or pain scores with nonabsorbable, absorbable synthetic, or biologic mesh for elective ventral hernia repair in contaminated fields.

Weighing the benefits: Exploring the differential effects of light-weight and heavy-weight polypropylene meshes in inguinal hernia repair in a retrospective cohort study

BackgroundInguinal hernia repair is a common surgical procedure, with more than 20 million cases yearly. Choice between mesh types varies in clinical practice. To compare light-weight polypropylene (LW-PP, 34–36 g/m2) and heavy-weight polypropylene (HW-PP, 95 ​g/m2) meshes. MethodsData from patients who underwent open inguinal hernia repair between 2020 and 2022. Selection criteria ensured homogeneity. Endpoints were to assess the impact of different mesh weights on overall health-related quality of life (HRQoL), using Short Form 36 (SF-36), and to monitor postoperative complications. ResultsTwo hundred patients were included in both groups. Lateral and direct hernias occurred in 60.5 ​% and 39.5 ​%. According to EHS, 31.5 ​%, 22.3 ​% and 46.2 ​% were classified as size 1, 2, 3. Follow-up showed similar HRQoL at 30-days, with a favorable trend towards LW-PP mesh offering fewer limitations, better comfort, and improved general health after 12-months. No difference in postoperative paresthesia, wound hematoma, and interference with daily activities. Conclusion1-year after surgery HRQoL evaluation highlights the non-inferiority of LW-PP. Mesh selection should be tailored, aiming at improving outcomes and postoperative comfort.

Routing impact of architecture and damage in programmable photonic meshes

Programmable photonic integrated circuits (PPICs) emerge as a novel technology with an enormous potential for ground-breaking innovation. Different architectures are currently being considered that dictate how waveguides should be connected to realize a broadly usable circuit. We focus on the effect of varying connectivity architectures on the routing of light. Three types of uniform meshes are studied, and we introduce a newly developed mesh that is called ring-connected straight lines. We provide an analytical formula to calculate exact distances in these meshes and introduce several metrics relating to routing to compare these meshes. We show that hexagonal tiles are the most promising, but the ring-connected straight lines architecture has a use case as well. Besides this, the effect of defect couplers is also studied. We find that the effects of these failures vary greatly by type and severity on the routability of the mesh.

Microstructure Modeling of Transport and Kinetics in Solid State Batteries with LLZO Solid Electrolyte Fabricated Using the Freeze-Tape-Casting Method

In traditional Li-ion batteries with liquid electrolyte, the transport of lithium ions in the electrolyte and lithium in the active material within a porous electrode are studied extensively. The continuum-scale modeling of these transport phenomena considers a homogenized simulation domain consisting of liquid electrolyte and solid active material with effective transport properties accounting for the heterogeneity [1]. There have been fewer studies that consider digitized versions of the experimentally imaged microstructure in continuum-scale modeling studies, particularly to study mechanics [2]. Despite of the computational challenges, there are inherent advantages in using fully resolved microstructure modeling to improve fundamental understanding of the relevant physical and chemical phenomena in porous electrodes, such as localized degradation and stress concentration. In the case of solid electrolytes, specifically scaffold-type LLZO solid electrolytes, microstructure modeling is of even more relevance, particularly to study anisotropic transport, localized degradation phenomena, stress and deformation leading to loss of contact, and chemo-mechanics. Thus far, microstructure modeling studies on experimentally obtained microstructure consisting of solid electrolyte and active material have been quite limited [3]. The studies that have explored this realm have employed voxel-based mesh to discretize the computation domain [3]. While these methods are sufficient proof of concept, the lack of precision in defining the interface separating active material and electrolyte when using voxel-based mesh provides a source of potentially significant numerical error. Without a highly resolved interface mesh, the total interfacial area increases artificially which leads to inaccuracies in calculations of local reaction rate and overpotential. A highly resolved, smooth interface is also necessary when simulating mechanical deformation and stress field in the microstructure. In the present investigation, we model mass transport and charge transport in the active material/electrolyte microstructure to simulate concentration and potential fields with varying mesh types in order to compare their effectiveness and characterize the error that can be attributed to the mesh type chosen, particularly in the case of voxel-based meshes. Additionally, we study the effect of microstructure domain length chosen in the two directions perpendicular to the shortest length (electrode thickness) as well as boundary condition formulation on the boundaries in these axes on the simulation results. The microstructures studied in this work are derived from the image stacks of the bi/trilayer LLZO solid electrolyte fabricated using freeze-tape-casting method [4]. Overall, the present work aims to develop a better understanding of the best practices in microstructure modeling, particularly when using microstructure image stacks obtained from fabricated samples.

Influence of Some Factors on Propolis Dilution by Honey Bees

Propolis is a sticky resinous substance collected from buds, leaves, stems of wild plants and processed by bees. Currently, bee behaviour during the collection of propolis, its botanical origin and sources of production have been studied. The process of propolis accumulation in bee nests and the factors influencing the intensity and productivity of bee colonies need to be further studied, which will allow to control the propolis productivity of bees in the future. To better understand the behavior of bees when liquefying propolis with enzymes from the mandibular glands, we conducted studies using specially designed collectors. Three different types of mesh were used in the collectors: ethylene vinyl acetate (EVA), polyethylene, and nylon. All three types of meshes had different hole diameters. As a result of the study, we determined the diameter of propolis droplets formed in all collectors, deviations from roundness, and the distance at which the droplets fly away from the edge of the glass substrates. We conclude that the type of mesh materials does not influence the behavior of bees in liquefying propolis. The size of the mesh holes affects the distance from the edge of the glass substrate to the centre of the propolis drops.

A discontinuous Galerkin method for the Brinkman–Darcy-transport problem

In this paper, a weighted discontinuous Galerkin finite element method and an upwind format are presented to solve the coupled Brinkman–Darcy flow and transport model. The flow in a highly permeable region of the model is governed by the Brinkman equations, and the percolation in the porous media is controlled by the Darcy equations, which are coupled by three interface conditions. The permeability coefficients in this model are strongly nonhomogeneous, anisotropic, and discontinuous; the transport equation is a convection-dominated problem; and the velocity field in the porous media domain does not satisfy the divergence-free condition. A weighted discontinuous Galerkin finite element method is used to solve the complex permeability coefficient problem and an upwind scheme is used to solve the convection dominated problem. The interface conditions can be naturally incorporated into the discrete formulation without introducing additional variables. Optimal error estimates are obtained for the semi-discretization and the full discretization with the backward Euler scheme in suitable energy norm. A series of numerical experiments are provided to illustrate the proposed method, including testing the convergence and accuracy of various types of meshes; simulating fluid flow in complex porous media such as obstacles, layered media, and curved interfaces; and studying the coupled flow behavior of surface-subsurface flows with contaminant transport.