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Introduction: In conjunction with impaction bone grafting (IBG), metal meshes have been proposed to minimise defects of the medial and superolateral walls in order to convert combined complex uncontained segmental defects into contained cavitary defects to facilitate IBG. Methods: The US National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews were queried for publications from January 1980 to March 2019 utilising keywords pertinent to total hip arthroplasty (THA), acetabular impaction bone grafting, clinical or functional outcomes, revision THA, or postoperative complications. Results: 7 articles were found to be suitable for inclusion in the present study. The mean modified Coleman methodology score for methodological deficiencies of the studies was 45.3 (range 38–59). Severe acetabular bone loss was present in 56% of cases having moderate bone loss in 18%, and mild in 26%. The all-cause reoperation rate was 7.4%, while the all-cause revision rate of the acetabular component was 6.2%. Conclusions: IBG with mesh is effective for selected patients with acetabular bone defects. Most patients with moderate bone loss as well as selected patients with large superolateral defects can be successfully treated with IBG combined with mesh. There is limited data to show that IBG with mesh might be associated with decreased survival rates in patients with severe lateral defects (Paprosky IIIA) combined with ischial or medial wall osteolysis who require combined medial and lateral meshes. In addition, patients with severe superomedial migration of the cup (Paprosky IIIB) should not be treated with IBG and mesh.

Metallic mesh is particularly advantageous for electromagnetic interference shielding in optical transparent devices. In this letter, we propose an equivalent period method (EPM) to achieve fast and effective shielding effectiveness (SE) simulation for multi-ring metallic meshes under various rotation angles, and experimental results indicate that a clear SE difference is observed with the rotation of multi-ring to verify the validity of EPM. The equivalent period can be obtained for multi-ring under different rotation angles by EPM, and the SE can be calculated by combining the equivalent period with the known SE evaluation models. The role of rotation angle for SE difference can be attributed to selective shielding under different polarization states, which can be explained by the negative correlation between the shielding performance and the equivalent period. The results have certain guiding significance for design and simulation of various metallic meshes with the rotatable basic unit.

Here a novel active ABA metasurface with wideband transmission/absorption is proposed, which consists of a metallic mesh layer (B layer) sandwiched by two layers of metallic layer (A layer). PIN diodes were embedded in the top and bottom A layers to manipulate the transmission/absorption states of the metasurface. Wide-band transmission upper than 80% in the frequency of 5.5 GHz-7.3 GHz and wide-band absorption upper than 80% in the frequency of 5.2 GHz-7.4 GHz have been achieved. The proposed active ABA metasurface have promising applications for the intelligent radome.

The preparation and characterization of superhydrophobic membranes formed on metal meshes (brass and bronze) by coating from stearic acid is presented. The membranes were prepared by two methods: electrolysis and acid etching. The electrolysis process is a one-step method performed by anodizing the mesh in ethanol solutions of stearic acid. Stearic acid concentration, support electrolyte concentration and electrolysis time were systematically varied. Nanostructures, including nanotubes, are induced on the metallic filaments. Analysis by FTIR, XRD, XPS and SEM of surfaces and precipitated material indicate that formed nanostructures are assemblies of metallic stearates on the surface (copper and/or zinc stearates). Superhydrophobicity (contact angles larger than 150°) was only achieved (in the electrolysis method) in cases where the formation of nanotubes was observed. On the other hand, the acid etching process is a two-step method: immersion of the meshes in acid solution of CuCl 2 or FeCl 3 , oxidizing the surface with formation of inorganic salts nano crystals, followed by immersion in stearic acid solution. Organic nanostructures (nanoribbons and/or nanopetals) were observed after the second step. Superhydrophobic surfaces (contact angles between 150 and 170°) were obtained for all the membranes. Both kind of membranes (electrolysis and etching) resulted effective in oil-water separation. Fil: Sosa, Mariana Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Lombardo, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. YPF - Tecnología; Argentina Fil: Rojas, Graciela. YPF - Tecnología; Argentina Fil: Oneto, María Elena. YPF - Tecnología; Argentina Fil: Negri, Ricardo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: D'accorso, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentina

In elderly patients with few remaining teeth, overdenture is a good treatment option. Roots beneath the denture protect the alveolar ridge, offer proprioception and improve retention, stability and masticatory efficiency of dentures. Customization of attachments available is a viable alternative for some patients in which prefabricated attachments cannot be placed or in which cost is a factor; to improve the final outcome of the treatment. Due to competitive commercialization, implant treatment has become the norm in current dentistry and the concept of tooth supported overdentures has eclipsed, but with proper case selection, thorough treatment planning and modifications in the denture such as customization of attachments, amalgam stops, cross-linked teeth, and metallic mesh can be applied to prolong the longevity and success of the attachment overdenture prosthesis.

Lightning strike damage on aircraft composite structure is very difficult to predict. The main source of this damage is the mechanical constraint generated by the lightning in interaction with the structure made of composite, protected with a metallic mesh and painted. The purpose of this paper is to propose a numerical model able to reproduce the surface overpressure generated by the explosion of the lightning strike protection (LSP) and its confinement with the paint. Comparisons of numerical displacements with lightning experimental ones are presented in order to analyse the predictability of the model. This is a first step in order to assess the damage in the composite structure depending on the design configurations (CFRP, LSP and Paint) when combined with a damage model.

This contribution describes the influence of the ratio of polyvinyl alcohol (PVA), TiO 2 and wire opening of metal meshes for the construction of a structured catalyst with a uniform coating, that present high adherence and photocatalytic activity. The best coating results were observed for a PVA/TiO 2 mass ratio of 0.37 and mesh opening of 546 µm. This coating exhibited a uniform distribution, high adherence and the maintenance of anatase and rutile phases. These aspects can be related to three variables: (i) the structure of the stainless-steel metal mesh, (ii) the thermal pretreatment and (iii) the amount of organic additive (PVA/TiO 2 ratio) employed in the suspensions. The most important achievement of this work was the fabrication of a structured catalyst with excellent stability, without losing activity for the degradation of endocrine-disrupting nonylphenol ethoxylate (NP 4 EO) in synthetic solution, without poisoning of the catalytic surface. In fact, the results showed that even with a real wastewater matrix, a high photocatalytic activity for NP 4 EO degradation (91%) was obtained, meaning that this structured catalyst can be applied to solve serious environmental problems as the contamination by endocrine-disrupting NP 4 EO, without subsequent catalyst recovery and recycle steps. Fil: de Moraes Da Trindade, Carolina. Universidade Federal do Rio Grande do Sul; Brasil Fil: da Silva, S.W.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Bortolozzi, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Banus, Ezequiel David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina Fil: Bernardes, Andrea Moura. Universidade Federal do Rio Grande do Sul; Brasil Fil: Ulla, Maria Alicia del H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera". Universidad Nacional del Litoral. Instituto de Investigaciones en Catálisis y Petroquímica "Ing. José Miguel Parera"; Argentina

The authors designed a randomised overlapping ring metallic mesh and built its evaluation model of electromagnetic interference shielding effectiveness. They simulated and analysed the effects of diameter 2R and period g on electromagnetic shielding effectiveness. The simulation and experiment results show that the electromagnetic shielding effectiveness is better than 23 dB in the 10–18 GHz band while its maximum normalised high-order diffraction optical energy is decreased to 0.00134%. The randomised overlapping ring mesh can realise strong shielding effectiveness and low image-degradation simultaneously.

After the inspections to the damage caused by the last earthquake in Ecuador, and considering the construction typologies of reinforced concrete buildings in Guayaquil and Manta (Ecuador), in order to rebuild or repair the masonry walls we must resort to composite materials with inorganic matrix (cementitious). Composite materials in FRP with an organic matrix (epoxy) are not appropriate because, with an increase of strength they have a brittle behavior, therefore without possibility of energy dissipation not having the ductility provided by a metallic mesh or cobalt-metallic mesh, which have the advantage of using it with a cementitious matrix of frequent use in the current technology. Since the photographic records and the design of those masonry structures allow determining in detail the dynamics of the damage, it is possible to add to the theoretical analysis an experimental verification on the behavior of masonry walls with reinforced plastering with FRP or with metallic mesh with inorganic matrix under seismic actions.

The equivalent circuit model based on the average period for periodic overlapping circle metallic mesh is proposed in this paper. The equivalent reactance coefficient b in the equivalent circuit model is revised according to the simulation results of Ansoft designer software. In order to guide the optimization of the electromagnetic shielding effectiveness of periodic overlapping circle mesh, the effects of the diameter 2R and period g on the electromagnetic shielding efficiency were simulated and analyzed. The simulation results show that the electromagnetic shielding effectiveness is better than 22dB in the 2-18GHz band. The periodic overlapping circle mesh can be applied to the area where the strong shielding effectiveness,high optical transmittance and low image-degradation are required simultaneously.

In this work, we proposed an optically transparent double-layer frequency-selective surface (FSS) based on interlaced multiring metallic mesh. By changing the large metal area of a conventional double-layer FSS into triangular-orthogonal distributed basic rings and nested rotated subrings, we achieved an FSS with high optical transmittance and low normalized high-order diffraction intensity while maintaining a flat passband and steep transition band. The results showed that our fabricated FSS had a normalized visible transmittance of 90.31%, stable filtering passband of ∼33.9 GHz, 3 dB bandwidth of 13.4 GHz, and uniform diffraction distribution, which are favorable characteristics for optically transparent FSS applications.

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In order to predict the appearance and porosity of the metallic two-bar warp-knitted mesh, a three-dimensional (3-D) loop model was developed by some key points on loop, and then based on the model meso structure of mesh was simulated. Firstly, a two-dimensional (2-D) loop geometry in metallic warp-knitted mesh was established. The loop geometry was described on the basis of the yarn property effect to loop sharp. And the underlap geometry was taken as an arc. To describe the 2-D loop geometry, coordinates of key points called databases were established. Then databases in 2-D loop geometry were relocated through the loop offset by stress distribution. Secondly, the 3-D loop geometry was ensured according to the yarn diameter, the angle between loop plane and fabric plane as well as the type of loops (front bar loop or back bar loop), etc. Finally, the coordinates of databases were imported to TexGen software to simulate the 3-D meso structures of the metallic mesh. By comparing simulation images with actu...

A solid material possessing identical electromagnetic properties as air has yet to be found in nature. Such a medium of arbitrary shape would neither reflect nor refract light at any angle of incidence in free space. Here, we introduce nonscattering corrugated metallic wires to construct such a medium. This was accomplished by aligning the dark-state frequencies in multiple scattering channels of a single wire. Analytical solutions, full-wave simulations, and microwave measurement results on 3D printed samples show omnidirectional invisibility in any configuration. This invisible metallic mesh can improve mechanical stability, electrical conduction, and heat dissipation of a system, without disturbing the electromagnetic design. Our approach is simple, robust, and scalable to higher frequencies.

In this work, a method for modeling the leaked radiofrequency radiation from electrical appliances is presented, with the aim of obtaining a model for a 3D ray-launching algorithm. The domestic microwave oven is the appliance under analysis, as it radiates a substantial amount of power and it is spread worldwide. The method uses numerical electromagnetic field simulations to obtain the exterior oven radiation. Due to the complexity of the metallic mesh of the oven door, a retrieval process has been implemented in order to accelerate the electromagnetic field simulation. This result is incorporated to a proprietary 3D ray-launching algorithm by obtaining equivalent radiation sources. Finally, the microwave oven leakage is obtained for the complete volume of an indoor scenario. The numerical results are then compared with experimental measurements, with good agreement. The proposed model is useful to predict accurately the leakage of the domestic microwave oven within a complete complex indoor scena...

Recent studies have shown that conventional meshes comprising pure titanium and its alloys can be used to assist the recovery of bone fractures in various parts of the human body, such as the face, jaw, skull and knee. In anticipation of an improved efficiency for these applications and other applications, this work analyses the thermomechanical behaviour of a type of metallic mesh that is fabricated with NiTi shape memory alloys (SMAs), which are smart metals that exhibit functional properties, such as the shape memory effect (SME) and superelasticity (SE). The development of NiTi SMA meshes with different cell designs, good mechanical strength and recoverable deformation to replace titanium meshes and enhance biomedical applications (as well as applications in other fields) can be considered a current technological challenge. In this framework, this study aims to perform the fabrication and mechanical characterization of NiTi SMA meshes produced by investment casting with three different cell geometries (circular, hexagonal and square) in two states (as cast and heat treated). The obtained results show that the manufactured meshes present functional properties even in the as-cast state, as thermoelastic phase transformation and deformation recovery on the order of 6% is demonstrated. The results show that between the heat treatment and mesh cell geometry, the latter factor is the most influential factor in the mechanical behaviour of the meshes. A brief numerical simulation of the tensile behaviour of the meshes is used to deepen the analysis of the influence of cell geometry on their mechanical behaviour. Overall, as-cast meshes with circular and square cells present a high stiffness under tension and bending. The produced meshes show enough thermomechanical features to enhance biomedical applications. These results support the replacement of conventional titanium alloys, which do not possess functional properties, with NiTi SMAs.

In mechanical engineering, truss structures have attracted much attention because of their mechanical strength and light weight. However, electromagnetic properties of truss structures have been rarely reported. We experimentally and numerically investigated a terahertz transmission through a truss structure composed of metallic meshes. In the experiments, a resonant transmission was observed through the metallic mesh truss structure. The frequencies and spatial distributions of the resonant modes were investigated in the numerical simulations. The frequencies of the resonant modes obtained from the numerical simulations agreed well with the observed frequencies. The field distributions of the resonant modes resemble those of the resonant modes of a Fabry–Perot resonator. Because truss structures are practically empty, they could be applied in realizing sensors to detect the chemical reactions of gases or molecular biomaterials in response to their changing refractive index.

Las caídas de rocas son un tipo de inestabilidad usual y frecuente en taludes en roca, la necesidad de protección frente a este tipo de fenómenos ha llevado al desarrollo de diferentes soluciones, entre ellas encontramos la estabilización de taludes mediante el uso de sistemas de malla metálica con pernos o anclajes. Los fabricantes han desarrollado manuales y softwares de diseño de estas mallas, sin embargo, estas herramientas son de uso exclusivo y con fines comerciales. Así mismo el desconocimiento general del diseño e implantación de estas soluciones, relacionado a la falta de claridad en el funcionamiento de estos elementos sobre el macizo rocoso, restringe el diseño y la colocación de este tipo de soluciones únicamente a los fabricantes. Teniendo en cuenta lo anterior, el presente trabajo tiene como objetivo establecer la influencia de las propiedades mecánicas y geométricas de los macizos rocosos y mecánicas de las mallas flexibles en el diseño de sistemas de estabilización para taludes en macizos rocosos, para lo cual se propone una nueva metodología para el diseño de estabilizaciones de taludes en macizos rocosos con mallas metálicas flexibles. Rock falls are a type of instability that is frequent in rock slopes. The need for protection against these types of phenomena has led to the development of different solutions, including stabilization of slopes with the use of wire mesh with bolts or anchors. The manufacturers have developed manuals and design software for these meshes, however, these tools are for commercial purposes. Likewise, the general lack of knowledge about the design and implementation of these solutions, restricts the design and placement of systems to the manufacturers. The present work aims to establish the influence of the mechanical and geometrical properties of the mass of rock and mechanical of the meshes in the design of stabilization systems for slopes, for which a new design methodology is proposed.

为寻求准确评估薄膜型金属网栅电磁屏蔽效能的方法,探索了薄膜型金属网栅在某频段可达到的电磁屏蔽效能.首先,分析了金属网栅膜光电特性常用的计算公式,指出电特性公式中材料无限导电的假定条件与客观事实不符,故其无法准确预估薄膜型金属网栅的电磁屏蔽效能.然后,根据屏蔽效能受感应电压和电阻比控制的理论,借鉴连续导电膜用方块电阻计算屏蔽效能的方法,提出了预估薄膜型金属网栅屏蔽效能的方法并给出了具体步骤.最后,采用激光直写工艺流程制备了薄膜型金属网栅,验证了理论计算结果与实验检测结果的一致性.检测结果显示:薄膜型金属网栅试片在30～1 500 MHz的屏蔽效能最高为30 dB;用检测方块电阻并代入连续膜经验公式计算得到的屏蔽效能为31.2 dB,用金属网栅膜常用公式计算得到的屏蔽效能为75 dB.数据显示用金属网栅膜常用电特性公式无法准确评估薄膜型金属网栅的电磁屏蔽效能,而本文所提方法便捷、准确、可行.

A transparent, hard silica glass SiO2 layer was formed on a conventional protective coat made of silicone [SiOCH32]n on a polycarbonate plate by the 157 nm fluorine F2 laser-induced photochemical modification of silicone into SiO2. Long exposure of the F2 laser to the sample produced cracks on the surface; a metallic mesh mask was set on the sample during F2 laser irradiation to suppress the cracks successfully. As a result, the thickness of the formed SiO2 layer could increase to approximately 1.3 µm without any crack, and the hardness of the sample also increased to approximately 2.8 GPa.

AIMS Avoiding side branch occlusion is challenging when treating bifurcation lesions. A newly designed stent system called the prewire channel stent (PWCS) with a side channel positioned between the metallic mesh material and the balloon is introduced. We aimed to compare the time taken to position the PWCS against that for a conventional stent. METHODS AND RESULTS The PWCS and a conventional stent were used in a pig model. The time taken from the starting point with the stent outside the body to reaching the bifurcation of the vessel ready for further procedures such as balloon dilatation through the stent mesh opening and double kissing balloon technique, etc., was compared in the conventional stent and PWCS groups. The time taken in the PWCS stent group included the time from sending the stent from outside the body to the desired position of the bifurcation of the vessels of the heart, releasing the stent and pulling back the balloon (SB time). The time taken in the conventional stent included the time from sending the stent from outside the body to the desired position of the bifurcation of the vessels of the heart, releasing the stent, pulling back the balloon (SB time), and wire exchange (WE time). The SB times for the PWCS and the conventional stent groups were not different (28.5±3.8 vs. 25.25±0.75 seconds, n=4). The PWCS group did not have "wire exchange," and had no WE time, which was 28.5±5.7 seconds in the conventional stent group. The total time spent in the PWCS group was 28.5±3.8 seconds, which was shorter than the 53.75±6.2 seconds (n=4, p

[EN] The drop impact onto porous surfaces has important applications in many fields, such as painting, paper coating, drug delivery and cosmetic sprays. In most of these applications, the optimisation of the deposition process is carried out empirically, without a proper understanding of the physics and a theoretical modelling of the spreading and the imbibition phenomena. The purpose of this study is to analyse droplet impacts on metallic meshes to define a general modelling strategy of the impact regimen on particular 2D regular porous surfaces. The application of this structure is relevant in process like filtration but also in the medical field, considering for example reconstructive surgery. By analysing the impact of droplets of water, acetone and a mixture of glycerol and water, having a diameter and an impact velocity in a range of 1.5-3mm and 2-4m/s, respectively, on meshes with a pore size ranging between 25 and 400 µm, a regime map was built considering 6 different impact outcomes. The outcomes were characterised by a deposition of the droplet on the substrate, or a partial imbibition, or a total imbibition. By increasing the impact velocity, a splash region was defined, which is still characterised by a final deposition, a partial imbibition and a total imbibition. It is found that the most influencing parameters are closely linked to the liquid properties and the impact velocity, more specifically liquid surface tension plays a major role in defining the impact outcome. In the case of Acetone, the lower surface tension brings to an almost instantaneous total imbibition whereas the experiments conducted using water and glycerol solution, showed a major distribution of the deposition regimes with respect to the other outcomes, due to the effect of a higher viscosity. It was found that the geometrical characteristics of the mesh such as pore size and wire diameter, play an important role as well in defining the total imbibition outcome. Finally, the defined transition maps, shows that for a certain combination of physical properties and initial condition, the outcome of the droplet impact is predictable.

Broadband antireflection coatings for passive terahertz (THz) components are extremely important in the application of THz technology. Metallic nano-films are commonly used for this purpose. Here a new approach to realize polarization independent broadband antireflection in THz range, based on a meta-surface design is experimentally demonstrated. The internal reflection of a broadband THz pulse (spectral bandwidth of 0.06 – 4 THz) at a Si/air interface can be fully suppressed with a Cr square mesh with deep-subwavelength dimensions. Small nonuniformity of the meta-surface structure can enhance the tolerance on structural parameters for achieving the AR condition. The design concept is applicable to other metals and frequency ranges as well, which opens a new window for future AR coatings.

This paper introduces the principle and manufacture process of a film-taped metallic mesh, and the influence of the parameters of metallic mesh film on optical and electromagnetic features has also been analyzed. By using the flexographic printing technology, the metal mesh film with the line widthes of 15, 203040μm and the period of 300μm on PET substrates have been made, and the maximal electromagnetic shield effectiveness is more than 15dB. The results indicate that the optical and electrical performance of the metallic mesh film is inconsistent, and it is better to select a thinner line width and smaller period to obtain optimal shielding effectiveness.