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We present a case of an 84-year-old patient with acquired bilateral superotemporal orbital fat prolapse. The disease occurs when there is dehiscence in Tenon’s capsule, allowing fat to herniate forward spontaneously. This can happen when there is a discontinuity of Tenon’s capsule. We discussed visual symptoms at presentation, surgical technique, and visual and aesthetic outcomes.

Custom 3D printed total talus implants have been used successfully as a functional alternative to arthrodesis or amputation in cases of severe talar destruction or loss. However, the ideal material and construct still remains to be elucidated. Current models have been made from aluminum ceramic, cobalt chrome, stainless steel, titanium, or metal combinations. The implants may be constrained (subtalar arthrodesis) or unconstrained (press fit within mortise). They may also be combined with a tibial prosthesis or used in isolation. The majority of currently published case studies examine unconstrained and isolated implants. This case study presents satisfactory 1-y outcomes in 3 cobalt chrome constrained total talar implants used in combination with a tibial prosthesis, and a literature review of total talus replacements.

Purpose To report our experience using a Tenon's cyst autograft in the management of tube exposure post Ahmed Glaucoma Valve implantation. Methods This is a retrospective case series. Results Four patients who underwent tube exposure repair using Tenon's cyst autograft were identified in our tertiary care center. The duration between initial Ahmed Glaucoma Valve implantation and tube exposure ranged between 3 and 36 months with a mean of 16 months (+/-14.35). All patients were followed post-operatively for a range of 4 to 24 months with a mean of 11.75 months (+/-9.03) and all remain exposure free at last follow-up. Conclusion The use of a Tenon's cyst autograft for the surgical repair of a tube exposure is valuable, as it involves using autologous scar tissue that is available in eyes that have undergone Ahmed Glaucoma Valve implantation. The patch autograft is technically easy to harvest, and represents a significantly lower cost when compared to other available options.

The seismic performance of the precast shear wall was improved by using a newly developed reinforced tenon to strengthen the precast joint, which is used to bear the shear force of the precast joint and reduce the effect of dowel action on the vertical connecting steel bars. The vertical connecting steel bars were only used to bear tensile and compressive stress and consume seismic energy. The seismic performance of reinforced tenon precast shear wall was investigated by quasi-static tests on one reinforced tenon precast shear wall specimen and one ordinary flat seam precast shear wall specimen. This study investigated the crack distribution and failure modes, precast joint slip of the two specimens, and the seismic performance parameters such as bearing capacity, stiffness degradation, ductility performance and energy dissipation capacity. The test results demonstrated that the reinforced tenon effectively reduced the slip of the joint surface and exhibited good ductility and energy dissipation capacity than that of the ordinary flat seam specimen, while the failure mode, bearing capacity, and stiffness were similar to that of the flat seam specimen.

This work verified the direct measuring method of the contact force and its relaxation behavior between mortise and tenon joints through withdrawal load resistance testing of T-shaped mortise-and-tenon joint specimens. Further, it also studied the influence of wood species, beech (Fagus orientalis Lipsky) and Mongolian Scots pine (Pinus sylvestris var. mongolica), interference fitness (0.1, 0.2, 0.3, and 0.4 mm; 0.2, 0.4, 0.6, and 0.8 mm), and wood grain orientation (radial, diagonal, and tangential) on the contact force and its relaxation. The results showed that the direct measuring method had good feasibility for measuring the contact force and its relaxation of the beech and it showed good feasibility on measuring initial contact force of pine. However, it showed low feasibility for measuring the relaxed contact force when the interference was 0.2 mm, but showed good feasibility on measuring the relaxed contact force with larger interference of pine. Interference fitness, wood grain orientation, and wood species had a significant effect on initial contact force and contact force after 5 h relaxation. This study showed feasibility and application scope of the method for direct measuring contact force and provided additional fundamental data to contribute to further study of the internal mechanical mechanism of mortise and tenon joints.

The aim of this study was to examine the effect of tenon and mortise joints on Young's modulus of wooden members and propose a correcting method of Young's modulus. Young's moduli of the specimens with two additional concentrated masses (CMs) and those of the specimens with tenon and mortise joints were obtained using the longitudinal vibration test. The frequency equation for the longitudinal vibration of a specimen with two additional CMs was experimentally proved. The maximum deviation of 17% in Young's modulus was observed when the specimens with tenon and mortise joints were treated as rectangular bars. The mass ratio (mass of a tenon and a mortise/mass of the main body) and the volume ratio (volume of a tenon and a mortise/volume of the main body) could be used for the aforementioned frequency equation. Using this method, it is possible for one to accurately estimate Young's modulus of a wooden member with a tenon and a mortise on a construction site.

The box frame is a common structure in modern furniture, especially for cabinets. Accordingly, the joint contact force of the frame is important in evaluating the stability of classified furniture. In this study, a new type of keyed joint was proposed to alter the dovetail joint used in box frame structures. The tensile strength of the dovetail joint and the keyed joint in the frame were evaluated, and the contact forces and failure modes of these two joints were compared. Three levels (T1, T2, and T3) were proposed for the ratio of groove depth (D) to inclined contact surface height (H), under the condition of the same joint spacing and inclination angle considering the effects of keyed joint size on the contact force. Meanwhile, experimental analysis was performed on both sides (S1 and S2) of the dovetail joint. Results showed that the contact force of the joint under the gluing condition decreased in the order of S2 > T2 > T3 > S1 > T1. In terms of failure modes, the keyed joint could be maintained in good condition, whereas failure of the dovetail joint always occurred at the root of the tenon in the S1 direction.

Purpose To describe the technique of modified adjustable flange scleral fixation using 6-0 polypropylene sutures for repositioning of subluxated intraocular lenses (IOLs). Setting Center for Applied Eye Research, Meir Medical Center, and the Ein-Tal Eye Center, Israel. Design Case series. Methods Subluxated capsular-fixated posterior chamber IOLs are secured to the sclera using 6-0 polypropylene sutures looped around the IOL haptics. This method can be performed for any type of IOL: hydrophobic, hydrophilic, silicone, or poly(methyl methacrylate); 1-piece or 3-piece; and with either closed-loop or open-loop haptics. It can also be used in conjunction with capsular stabilizing devices. Results In the 18 cases performed, successful repositioning with stable and central fixation of the IOLs was achieved. One eye required a repeated surgery due to suture slippage. The eyes recovered relatively quickly with noted quiescence as early as 1 week postoperatively. Patients did not complain of ocular irritation from the subconjunctival flange up to the 6-month follow-up period. In 1 case, a flange was exposed postoperatively but the patient refused additional intervention and developed intraocular infection 7 months postoperatively. Conclusions The adjustable 6-0 polypropylene flanged technique for IOL repositioning and scleral fixation was a relatively quick and simple method for management of subluxated IOLs. Complete coverage of the flange by conjunctiva and Tenon layer must be confirmed at the end of surgery.

With the grouting material as focus, this study aims to guarantee that the joint with tenon and mortise constructing a metro station has the necessary waterproof performance, which shall not be poorer than the mechanical properties of the concrete with joints itself, and fine structural integrity. With groutability at low-temperature and available operational time as basis, low-temperature epoxy was selected as the grouting material for the joints. The silica powder of particular particle size and mass was added for modifying the physical performance of grouting material. A series of physical and mechanical tests were conducted in an attempt to achieve the optimal particle size and mix ratio provided that costs were reduced as practically as possible. Also, the flexural capacity of the joint filled with the above grouting material was demonstrated via the combined equal-proportion joint axial bend test.

To determine the expression of hypoxia-induced factor-1α (HIF-1α) and its downstream factors in human Tenon's capsule fibroblasts (HTFs) and changes in HTFs biological functions, we explored the role of HIF-1α in HTFs under hypoxia to provide a basis for studying the regulation of HIF-1α in wound healing after glaucoma surgery.we established HTFs hypoxia modelHIF-1α protein expression increased under hypoxia, peaked from 4-24 h, and then decreased. The secretion of VEGF and TGF-β increased with prolonged hypoxia time. VH298 and KC7F2 upregulated and downregulated the levels of VEGF and TGF-β, respectively, suggesting that HIF-1α upregulates and downregulates the levels of VEGF and TGF-β in HTFs under hypoxia, respectively. HIF-1α upregulated the proliferation, migration and collagen synthesis of HTFs under hypoxia.Regulating HIF-1α and its downstream factors effectively regulated HTFs proliferation, migration and collagen synthesis. HIF-1α is a promising regulator in the study of wound healing after glaucoma surgery.

This paper investigated the effect of the tenon length on the strength and stiffness of the standard mortise and tenon joints, as well of the double mortise and tenon joints, that were bonded by poly(vinyl acetate) (PVAc) and polyurethane (PU) glues. The strength was analyzed by measuring applied load and by calculating ultimate bending moment and bending moment at the proportional limit. Stiffness was evaluated by measuring displacement and by calculating the ratio of applied force and displacement along the force line. The results were compared with the data obtained by the simplified static expressions and numerical calculation of the orthotropic linear-elastic model. The results indicated that increasing tenon length increased the maximal moment and proportional moment of the both investigated joints types. The analytically calculated moments were increased more than the experimental values for both joint types, and they had generally lower values than the proportional moments for the standard tenon joints, as opposed to the double tenon joints. The Von Mises stress distribution showed characteristic zones of the maximum and increased stress values. These likewise were monitored in analytical calculations. The procedures could be successfully used to achieve approximate data of properties of loaded joints.

Despite decades of research, fibrosis still remains a significant challenge for medicine in many different fields. Although there is a general model of fibrosis, the causes and characteristics of the various pathologies are as diverse as the variety of organs and tissues that can be affected by fibrosis. Moreover, fibrosis also impedes the long-term prospects of success in implantation surgery. One possibility to address this challenge is the development of biocompatible implants featuring drug delivery systems loaded with antifibrotic pharmaceuticals. Due to diverse regulatory mechanisms in organs, tissues and also cell types, these active substances must consequentially be designed for diverse specific applications. Compared to fibrosis in organs like lung or liver, these mechanisms were poorly addressed in ophthalmologic research, but it is known that transforming growth factor beta (TGF-β) plays a key role. This gene expression study revealed 30 genes being upregulated more than two fold in TGF-β1 treated human primary tenon fibroblasts (hTF). Furthermore, 15 genes were found to be downregulated more than two fold. Tumor necrosis factor (TNF), vascular endothelial growth factor A (VEGFA) and inhibin beta (INHBE) were particular strongly regulated in TGF-β1 treated hTFs.

With the goal to restore ankle and foot function also in the long term, custom-made prostheses are becoming more frequently possible solutions for severe bone loss and avascular necrosis of the talus. A young professional rock climber was implanted with a custom-made talonavicular prosthesis, and short-term (30 months) assessment has been published. A thorough assessment at the intermediate term (60 months), with state-of-the-art gait and medical imaging analyses, is reported here. Level walking and more demanding motor tasks were analyzed with both a full-body and a multisegment foot protocol on the operated and contralateral limbs. Cone-beam computer-tomography was also used to obtain 3-dimensional (3D) position and orientation of bone models on the operated ankle. These models were also used for a 3D video fluoroscopy analysis, with the ankle in 3 joint positions at the extremes of motion. Distance map analysis was performed to check for possible changes over time of bone morphology and joint contact areas, in all 3 joint positions. Very satisfactory functional results were observed, with large and symmetric joint motion and physiological muscular recruitment even in demanding motor tasks. Distance map analyses revealed that very small morphologic and contact patterns changes occurred in the replaced ankle between 30 and 60 months. Concerns about possible wear of the cartilage in the tibial mortise are not yet supported by experimental evidence.

Culvert is an important part of roads whose healthy operation is related to the efficiency and safety of road transportation. Therefore, it is very important to evaluate the safety of culvert structure by load test. Four types of prefabricated reinforced concrete box culverts (integral BC, round hinged BC, flat seam BC, and mortise BC) were designed in this paper. By designing a scale model test, the sensor system was used to test the mechanical properties of BC, which included dial indicators, strain gauges, and a pressure sensor. The finite element analysis based on material nonlinearity and contact nonlinearity of round hinged BC and integral BC was carried out. After validating the finite element models, mechanical properties of reinforcement and concrete of BCs were analyzed. The experimental results show that the failure mode of BC was tensile failure of concrete at the bottom of top slab under bending action, and integral BC had the maximum carrying capacity. The contact behaviour of sliding and rotating at hinge joints caused the first principal tensile stress of concrete at the internal surface of the side wall below hinge joints.

Concrete hollow blocks have the advantages of simplified construction, reduced construction time, and better thermal performance, and can thereby achieve energy conservation in building engineering and significantly improved thermal and mechanical performance. A new tenon composite block is presented to achieve better self-thermal insulation and mechanical performance by integrating thermal materials into blocks. The tenon composite block application requires satisfying mechanical and seismic performance. Therefore, to prove the mechanical and seismic performance of the tenon composite block, a low cyclic loading test was performed on two self-thermal insulation wall specimens: the tenon composite block and the “Martha” block (used as the comparison specimen). The crack distributions, failure modes, force–displacement data expressed using hysteresis and skeleton curves, mechanical parameters of strengths, displacements, ductility coefficients, stiffness degradations, and equivalent viscous damping coefficients of the two specimens were analyzed in the low cyclic loading test. By analyzing the specimen crack distributions and failure modes, the tenon composite block was proven capable of effectively connecting the heat insulation and loading bearing parts. The differences in the force–displacement data and the mechanical parameters between the tenon composite block and “Martha” block specimens, such as the higher strength and stiffness of the tenon composite block specimen and similar ductility performance with the widely applied “Martha” specimen, were mainly caused by the size differences between the tenon composite block and “Martha” specimens. Finally, suggestions for tenon composite block applications are proposed to overcome the limitations of the tenon composite block’s ability to consume seismic energy.

The wooden columns in timber structures of ancient buildings have column foot tenons of various sizes. The main reason for these differences is their use for different roof loads. Six full-scale specimens with different sizes of column foot tenon were designed and manufactured. The tree species used for the specimens was larch. The quasi-static test was conducted on the specimens that were used in timber structures of ancient buildings. The effects of column foot tenon size on the mechanical properties of larch wooden columns were studied. The moment-rotational angle hysteretic curves, moment-rotational angle skeleton curves, ductility, stiffness degradation, energy dissipation capacity, slippages between the wooden column and the plinth, and the damage of the column foot tenons were examined. The test results showed that the column foot tenon played an important role in the mechanical behavior of the wooden column under low-cycle reversed cyclic loading. The rotation of the column foot tenon improved the energy dissipation capacity of the wooden column. As the rotational angle of the column base increased, the column foot tenon had different degrees of damage. Different sizes of column foot tenon had their own advantages and hysteretic behavior.

Glue tenon joints are widely used in wood products. The face pressing method of the tenon joint elements is an economical alternative to traditional milling. The industrial implementation of the new method requires a reasonable choice of process operating parameters that ensure high quality processing with minimal resource costs. This multicriteria problem belongs to the field of operations research and is solved by mathematical modeling methods. The goal of the work is to determine the rational values of the parameters of the end face pressing process of rectangular eyes in blanks from wood of typical species: coniferous (pine), broad-leaved diffuse-porous (birch), leaf ring-porous (oak). The development of the objective function for the optimization procedure was carried out on the basis of the principle of fair compromise with the reduction of particular criteria to dimensionless form. To construct the objective function, we used regression models that describe the output parameters of the process: the pressing force, the hardness of eye bottoms, and the depth of the deformed zone. The search for solutions to optimization problems was performed using the generalized reduced gradient method in the Microsoft Excel software package. The rational values of the input parameters (moisture content, depth and width of the eyes) and the expected values of the output parameters for each of the studied species have been determined. Recommended moisture values for blanks from pine wood are 8%, birch - 9.5%, oak - 7%; the depth of the pressed eyes is 11, 8 and 9 mm, respectively, the width of the eyes is 4 mm. The objective function has the potential in the direction of reducing the width of the eyes, which can be used to improve the strength characteristics of adhesive joints on multiple extruded spikes.

Compressive and tensile strengths were considered for a box connected by dovetail keys under different mortise-and-tenon sizes. Poplar wood modified by melamine resin (MF modified poplar wood) was chosen as the experimental material, and the experimental study was carried out on the box using the concentrated loading method. The results showed that the ratio (T) of hole depth to slope height had a significant effect on the structural strength of the box connected by dovetail keys when other dimensional parameters were the same. When T was equal to 75%, the compression and tensile strength of the box was the highest, and the joint had better recovery and deformation ability. When T` was equal to 50%, the box strength was the worst, and the joint damage was the most serious in both types of loading. In addition, the measurement standard of the displacement was determined through preliminary experimentation. The compression quantity was 8 mm, and the stretching quantity was 5 mm. The latter experiment showed the reliability of the pre-experiment.

The main complication of primary pterygium surgery is the recurrence of the pterygium. In the present study, we aimed to compare a classical technique and facilitated tenon-free conjunctival autograft preparation and a limited tenon removal technique in pterygium surgery in terms of recurrence rate, complications, and operation duration.This is a retrospective, comparative, observational study. Group 1 comprised 120 eyes of 115 patients who underwent pterygium excision with a new facilitated tenon-free conjunctival-limbal autograft preparation and limited tenon removal technique between May 2017 and October 2019. Group 2 comprised 117 eyes of 113 patients who underwent pterygium excision with a conventional conjunctival-limbal autograft technique between January 2016 and May 2017.The mean follow-up time after surgery was 18.2 ± 5.8 months in group 1 and 19.1 ± 6.3 months in group 2 (p = 0.25). The mean operation duration was 5.54 ± 1.22 (4 - 7) minutes in group 1 and 8.23 ± 1.26 (8 - 10) minutes in group 2 (p = 0.02). Flap edema was present in 33 eyes (28.2%) in group 2 and in 11 eyes (9.16%) in group 1. Flap edema was significantly higher in group 2 (p 0.001). At the end of the 1-year follow-up of the patients, we observed recurrence in only one (0.83%) eye in group 1 and 14 (11.96%) eyes in group 2. The recurrence rate of group 1 was significantly less than that of group 2 (p 0.001).The simplified technique of tenon-free conjunctival autograft preparation and limited tenon removal yielded better clinical outcomes without serious complications. Additionally, this technique shortened the surgical time and reduced surgeon-dependent factors.ZIEL: Die Hauptkomplikation der primären Pterygiumchirurgie ist das Wiederauftreten des Pterygiums. In der vorliegenden Studie wollten wir die klassische Technik und die erleichterte Technik der Tenon-Kapsel-freien konjunktivalen Autograftpräparation mit der limitierten Technik der Tenon-Kapsel-Entfernung in der Pterygiumchirurgie hinsichtlich Rezidivrate, Komplikationen und Operationsdauer vergleichen.Dies ist eine retrospektive, vergleichende Beobachtungsstudie. Gruppe 1 umfasste 120 Augen von 115 Patienten, die sich zwischen Mai 2017 und Oktober 2019 einer Pterygiumexzision mit einer neuen erleichterten Tenon-Kapsel-freien konjunktival-limbalen Autotransplantatpräparation und einer limitierten Tenon-Kapsel-Entfernungstechnik unterzogen. Gruppe 2 umfasste 117 Augen von 113 Patienten, bei denen zwischen Januar 2016 und Mai 2017 eine Pterygiumexzision mit konventioneller konjunktival-limbaler Autografttechnik durchgeführt wurde.Die mittlere Nachbeobachtungszeit nach der Operation betrug 18,2 ± 5,8 Monate in Gruppe 1 und 19,1 ± 6,3 Monate in Gruppe 2 (p = 0,25). Die mittlere Operationsdauer betrug 5,54 ± 1,22 (4 – 7) Minuten in Gruppe 1 und 8,23 ± 1,26 (8 – 10) Minuten in Gruppe 2 (p = 0,02). Ein Lappenödem war in Gruppe 2 bei 33 Augen (28,2%) und in Gruppe 1 bei 11 Augen (9,16%) vorhanden. In Gruppe 2 war das Lappenödem signifikant höher (p 0,001). Am Ende der 1-jährigen Nachbeobachtung der Patienten beobachteten wir ein Rezidiv in nur 1 (0,83%) Auge in Gruppe 1 und 14 (11,96%) Augen in Gruppe 2. Die Rezidivrate von Gruppe 1 war signifikant geringer als die von Gruppe 2 (p 0,001).Die vereinfachte Technik der Tenon-Kapsel-freien konjunktivalen Autotransplantatpräparation und der begrenzten Entfernung der Tenon-Kapsel führte zu besseren klinischen Ergebnissen ohne schwerwiegende Komplikationen. Darüber hinaus verkürzte diese Technik die Operationszeit und reduzierte die chirurgenabhängigen Faktoren.

This article describes the process of firing aluminum nitride substrates, which is a process that occurs under its characteristic conditions: high temperatures of over 1800°C and a reducing environment. This article also presents the fact that high quality substrates having desirable properties such as high thermal conductivity and parallelism between layers can be achieved. This article also describes how optimal firing modes can be established using a special sagger design based on boron nitride. The designed sagger is a container that consists of a body, which is a rectangular box; a bottom; and plane–parallel separating plates with supports. To create a local (inside the sagger) clean recovery medium, mortise and tenon joints that interlock are provided between the body and bottom and the interlocks are filled with a heat-resistant inert powder.

Background: The quality of ophthalmic anesthesia is an important component of the surgical procedure. There is no absolutely well-tolerated local eye anesthetic technique. However, it is important to choose a technique with high efficacy and safety. Objective: This study aimed to compare the efficacy and safety of peribulbar block using medial canthus single injection and posterior sub-tenon injection techniques. Methods: This prospective observational study was carried out at the Research Institute of Ophthalmology, Cairo, Egypt during the period from March to December 2018. Consecutive 60 patients of both sexes, aged >18 years-old, scheduled for bilateral strabismus surgery were enrolled in this study. In one eye of the sixty patients, medial canthus single injection peribulbar anesthesia was used (Group A), whereas posterior sub-tenon technique was applied in the other eye (Group B). Results: The median total ocular akinesia score was significantly higher in group A than in group B when assessed at 1, 3, and 5 min (p < 0.001). Each of the intraoperative (at 5 min) and postoperative pain scores showed no significant differences between the two groups (p > 0.05). However, the median scores of surgeon and patient satisfaction were significantly higher in group A compared with group B (3 vs. 2 each, p < 0.05). No patient developed occulocardiac reflex or postoperative nausea and vomiting. Conclusion: Peribulbar anesthesia by medial canthus single injection showed better akinesia of the globe than sub-tenon injection technique. Otherwise, both techniques were equally effective and safe.

This article presents an experimental and numerical study on seismic performance of semi-tenon joints reinforced by steel angle in traditional timber buildings. Five specimens with two different reinforced connections and one unreinforced connection subjected to low-cyclic reversed loading on the bending moment are examined. The unreinforced connection consists of left and right beams inserted into the column that has been used in setting up the mortise before assembly. The first type of reinforced connection is formed by bottom steel angles bolted to the column and jointed to the beam by means of bolts. The second type of reinforced connection is made up of top and bottom steel angles bolted to the column and connected to the beam relying on vertical and transverse bolts. Moreover, two reinforcement techniques aimed at enhancing the seismic performance of semi-tenon joints are investigated, including the change of steel angle limb length and the variation of steel angle limb thickness. The test setup, joint connection, reinforced conditions, and material properties are introduced through detailed account of the experimental results and observations. The key behavioral patterns are identified from the experiments and the main response characteristics such as hysteresis, stiffness, flexural capacity, energy dissipation, and the failure mechanism. This article demonstrates that the steel angle can enhance the flexural capacity of the semi-tenon joints significantly. Besides, the use of greater limb thickness steel angle is shown to be an effective detail for adequately increasing the flexural capacity and rotation stiffness of the joints. Finite element simulations of experiments are also conducted, together with a detailed description of the modeling methods, so as to gain further insight into the influence of various factors on the behavior of joints.

The study examines the degree of deviation from the nominal size of the produced open full-width mortise and tenon joint elements for their optimal pairing based on the measured thickness and gap width data. The characteristics of the measuring devices used were analysed by the repeatability and reproducibility test. The compressive strength of the single-glued joints (where only the surfaces of the tenon were glued) and double-glued joints (where the surfaces of both the mortise and tenon elements were glued) for various joint fit categories was also determined. It was found that despite the huge number of produced test specimens and their measurements, the joint fits could be maintained with the milling machine and tools. The thickness of the joint could be characterized by measuring the data at the centre of the tenon, whereas the gap width of the mortise could be characterized by measuring the data on the side of the tool leaving the wood. The double-glued joints showed higher breaking force and displacement values as compared to the single-glued joints. The joints were found to be the strongest at a tight fit of 0.1 mm.

In prefabricated modular steel building, joint plays an important role in the structural behaviour and transfer of load among connected modules. In this paper, a new type of bolted joint with tenon-gusset plate as horizontal connection and long beam bolts as vertical connection has been proposed. The nonlinear structural behaviour of the novel joint was analysed against static and quasi-static cyclic loadings by using finite element (FE) software ABAQUS. Numerical study was carried out to predict the lateral load carrying capacity, bending moment capacity, rotational stiffness, failure modes and seismic behaviour of the joint. Connection was simplified with nonlinear spring connector and 3-D beam elements. Parametric study was carried out on the length of column tenon and gap between adjacent modular units. The results revealed that against lateral loads, the gap was generated between the upper and lower parts of joint which resulted in the bearing failure of floor beam (FB). The length of column tenon has obvious while gap between modules showed marginal effect on load carrying capacity and structural behaviour of joint. The simplified joint accurately mimicked load–displacement curve and structural behaviour of detailed joint. Then, FE analysis was justified by analysing test results of innovative connection in the reference. With these evidences, the veracity of the FE analysis for studying nonlinear behaviour of novel joint was confirmed.

Extraocular muscle pulley bands were described by Tenon in 1805 as "faisceaux tendineux" acting as "poulies de renvoi." The Passive and Active Pulley Hypotheses propose that these connective-tissue bands between muscle and bony orbital rim limit vertical shift of the horizontal rectus muscle belly in up- and downgaze, caused by the muscle's tendency to assume the shortest path from origin to insertion. The band's attachment to the muscle moves 20 mm sagittally when the eye looks from 50° left to 50° right, however, impeding vertical muscle stabilization. Sliding of the muscle in a sleeve would permit sagittal movement, but four anatomical studies could not confirm that. The band would have to be elastic: We measured it after orbital exenteration and found it to be slack, however, and once extended, very stiff. Our research group in Amsterdam suggested in 1984 that the retrobulbar fat and its enveloping connective-tissue sheets including the intermuscular membrane keep muscle bellies in place. We compared horizontal-rectus-muscle positions in up- and down-gaze using frontal CTs through the posterior pole of the eye. The bellies stayed in place while, anteriorly, the tendons bent up- and downward. We also found that the paths of horizontal rectus muscles were curved outwards in horizontal CTs. We surmised that retrobulbar pressure in the fat, resulting from four rectus muscles pulling the eyeball into the orbit, is contained by rectus muscles and connective-tissue sheets and that the resulting tension in the sheets keeps the muscles in place. Years later we repeated the CT study in a Crouzon patient whose bony orbital rim was displaced 2cm posteriorly, preventing pulley-band fixation to the bone: No vertical shift of horizontal rectus muscle bellies occurred in up- and down-gaze. Finally, we developed a mathematical finite-element model of orbit, muscles, fat and eyeball to study whether fat with enveloping connective-tissue sheets could keep eye muscles in place. In simulated eye movements, the retrobulbar fat, with low elasticity as found in vivo, not only kept the eyeball in place but also horizontal rectus muscle bellies in up- and down-gaze and vertical recti in left- and right-gaze.

With the development of electric vehicles, more and more high requirements for the lightweight design on EV body are put forward. This paper aims to study a new structure, aluminum alloy mortise-and-tenon structure, which is used for lightweight EVs. Two new types on aluminium alloy MT-T joint specimens are designed and tested under low-cycle reciprocating loading. And the failure characteristics, hysteretic curve, skeleton curve, restoring force model and energy dissipation curve are obtained by analyzing the experimental data. Moment and rotation angle relationship is conducted by joint geometric deformation and equilibrium relation. Based on theoretical model, a simplified bilinear model has been proposed for engineering calculation. When the beam bending performance is qualitatively analyzed, the theoretical model, simulation model and bilinear model are verified through experiments and finite element method simulations. The results show that mortise-and-tenon T joint main failure modes are plastic deformation caused by the upper contact area squeezed each other and the lower contact area divorced each other. Furthermore, it can be obtained from the theoretical model that MT-T joint deformation process consists of elastic segment and elastoplastic segment. Theoretical model, simulation model and bilinear model agree well with the experimental results. This fruit gives a useful reference to composite material used in EVs.

The existence of gaps between tenon and mortise in traditional timber structures is very common. Accurate estimation of its probability distribution is essential for the stress and reliability analysis. This paper presents the probability distributions for the horizontal and vertical gaps based on measurement. The gap data were collected from four traditional timber buildings in a heritage building complex by manual on-site measurement. Statistical analysis of data for each building was performed. Results show that the statistical features of all four buildings are similar. All the measured gap data were then categorized into two groups in horizontal and vertical directions. The optimal distribution to represent these gap data was obtained using the probability plot correlation coefficient method and Anderson–Darling test. Results demonstrate that the Weibull distribution is the most appropriate model for fitting both the horizontal and vertical gaps. Parameters of the distributions were obtained from the maximum likelihood estimate. A finite-element (FE) numerical investigation for a joint was conducted. Gaps were randomly created using the obtained probability model in the joints. Static analysis results show that the gaps will weaken the mechanical behavior of the tenon–mortise joint, especially the initial stiffness. Compared with the horizontal gaps, the vertical gaps affect the mechanical properties of the joint more directly.

The results of theoretical and experimental investigations of pressure distributions in a shear laminar flow between rotating eccentrically located cylinders are presented. It is shown that a change in the pressure in the slit gap is attributed to two mechanisms: to the "wedge effect" from the eccentrically located rotating tenon in the bearing and to the heat supply due to the adiabatic change of the volume, dissipative processes, and heat transfer.

Milling recessing machines are designed to select mortises with end mills of the rectangular-shaped sockets. To the characteristic features of these machines, distinguishing them from the machines of the milling group is the additional oscillatory movement of the milling cutter on the chain ridged machines. The sockets are selected with the rectangular shape of the milling chain. These machines are operated at constant spindle speeds. Therefore, in these machines there are no multistage gear boxes with a large number of the spindles. These features lead to the fact that the vibrations of the cases of the speed boxes of woodworking machines (unlike metal-cutting machines) are much less and, accordingly, the intensity of their sound radiation is also less. The frequency of the rotation of the cutting tool is significantly higher. Therefore, it can be assumed that the main source of the noise that exceeds sanitary standards is the workpiece cutting tool system. The purpose of theoretical studies with obtained results show the analytical dependencies of the active sound pressure levels created by the cutting tool of the milling recessing and chain mortise machines providing for geometrical, physic-mechanical parameters of the tool and technological cutting conditions. The used acoustic source models are monocle for the tool of the milling recessing machines and a linear source for the milling chain and the noise levels obtained on their basis showed that for engineering calculation it is necessary to determine the oscillation velocities of the sources on their own oscillation modes. The speeds of the oscillations are determined from the differential oscillation equations; the solutions are obtained taking into account the cleat boundary conditions. The calculation of the noise spectra makes it possible at the design stage of both similar equipment and technological processes of the wood processing to determine the magnitudes over the maximum allowable values and in fact at the same stage to design noise protection systems.

Background The purpose of this study was to quantify the effects of rigid syndesmotic fixation on functional talar position and cartilage contact mechanics. Methods Twelve below-knee cadaveric specimens with an intact distal syndesmosis were mechanically loaded in four flexion positions (20° plantar flexion, 10° plantar flexion, neutral, 10° dorsiflexion) with zero, one, or two 3.5-mm syndesmotic screws. Rigid clusters of reflective markers were used to track bony movement and ankle-specific pressure sensors were used to measure talar dome and medial/lateral gutter contact mechanics. Results Screw fixation caused negligible anterior and inferior shifts of the talus within the mortise. Relative to no fixation, mean peak contact pressure decreased by 6%–32% on the talar dome and increased 2.4- to 6.6-fold in the medial and lateral gutters, respectively, depending on ankle position and number of screws. Conclusions Two-way ANOVA indicated syndesmotic screw fixation significantly increased contact pressure in the medial/lateral gutters and decreased talar dome contact pressure while minimally altering talar position.

Chinese woven timber arch bridge is an important part of the precious cultural heritage handed down from ancient times. Its construction technology has been inscribed on the List of Intangible Cultural Heritage in Need of Urgent Protection by UNESCO in 2009, and twenty-two bridges of this kind have been listed in the tentative list of the Chinese World Cultural Heritage since 2012. Made by longitudinal and transverse straight logs woven together with mortises and tenon joints, the main arch is not a planar structure nor a general three-dimensional spatial one, and its mechanical behavior cannot be computed by the traditional structural analysis method. In this study, loading tests and FE analyses on the woven arch, and field tests and FE analyses on a really bridge are carried out. For the woven arch, two joint types, rigid and hinged joints are considered in the tests and analyses. The results show that: (1) the deflection shapes of woven arch models with rigid joints and hinged joints are similar; (2) the deflection of a hinged woven arch is larger than that of a rigid one; (3) the two systems of a woven arch can work together simply by the contact between them, but in some loading cases, some portions of them will separate and no force is transferred between them; (4) the mechanical behavior of the woven arch is similar to that of the two-hinged arch. In other words, it is also subjected to horizontal thrusts under vertical loads, but the compression force is the dominant one; and (5) the modeling method of the woven arch is applicable to Chinese timber arch bridges.

To evaluate the efficacy of dexamethasone (DXM) through sub-tenon sustained controllable drug delivery system (SSCDDS) for treating severe acute experimental uveitis.Rabbits were treated with either DXM (treated group) or normal saline (control group) through SSCDDS. Clinical signs of uveitis were assessed at days 1, 3, 5, 7, and 14 after treatment. Histopathologic examinations were performed to evaluate inflammatory cell infiltration on posttreatment days 7 and 14.All signs of experimental uveitis were reduced by SSCDDS of DXM according to clinical criteria, and the treated group had significantly less inflammation than the control group (Sub-tenon sustained controllable delivery of DXM effectively suppresses severe acute inflammation in a rabbit model of uveitis. The proposed minimal invasive system might be a promising candidate for managing severe ocular diseases.

This paper summarises the regulation mechanism of the traditional and emerging surface strengthening treatments – mechanical shot peening (SP) and laser shock processing (LSP) treatment, re...

Spurred by developments in digital fabrication, there has been an increase in the application of the Integral Mechanical Attachment (IMA) technique in timber plate structures. Despite its increase in popularity, there have been very few systematic investigations of the mechanical characteristics of IMA timber-to-timber connections. Focusing on in-plane shear, the force-deformation response of Through-Tenon joints is experimentally investigated, and their overall performance is assessed. The effect of influential design parameters is studied including the material type (Kerto-Q and Beech-Q), fiber orientation (parallel and perpendicular to the loading direction), and the tab insertion angle (45 degrees, 60 degrees, and 90 degrees). Twelve specimen groups, each with five replicates are tested. For the specimens with fibers oriented parallel to the loading direction (fiber-parallel specimens), a brittle failure is observed due to early rupture in the cross layers. On the other hand, more ductile behavior is observed for the specimens with fibers oriented perpendicular to the loading direction (fiber-perpendicular specimens) due to the compression forces perpendicular to the grains. Among the Kerto-Q specimens, the ones with a 60 degrees tab insertion angle have the greatest in-plane strength. Moreover, an increase in the tab insertion angle results in a decrease in the yield deformation capacity and an increase in the slip modulus, ultimate deformation capacity, and ductility. Among Beech-Q specimens, the fiber-parallel cases and the fiber-perpendicular cases with a tab insertion angle of 60 degrees and 90 degrees have the highest in-plane strength, respectively. Also, the slip modulus increases with the tab insertion angle for the two fiber orientation cases. The ductility of the fiber-parallel Beech-Q specimens is unaffected by a change in the tab insertion angle. Overall, very small differences are observed between the yield and peak strengths and most specimens have been classified as having low ductility. (C) 2019 Elsevier Ltd. All rights reserved.

The purpose of the article is introduction to the scientific turnover of a unique find discovered on the archaeological site of the Isker hillfort – an iron mortise lock. The relevance of the study is conditioned by the fact that mortise locks, as a rule, are poorly preserved and, in general, were not as widespread as padlocks, and in rare publications there is no detailed description of the remaining parts. The lock from Isker is distinguished by good preservation, which made it possible to examine in detail the mechanism of locking device and to make its detailed reconstruction. On the basis of considered analogies, it was concluded that the lock, in its design features, is similar to the locks popular in Eastern Europe and Siberia in the 15th – 18th centuries, differing from the latter by a special latch device. The difference in the latch device led to conclusion that the locks were made by local blacksmiths. Multiple findings of parts of interior locks in Isker show that in everyday life citizens used trunks fitted with locks of two different design schemes. This made it possible to supplement the existing classification by emphasizing two variants of locks, which were previously considered within the framework of a single type of interior all-metal locks.

This paper aims to characterize the force-deformation response of through-tenon wood-wood connections subjected to tensile loads. Four beech LVL timber specimen groups with variations in the fiber orientation, and the tab insertion angle (45°, and 60°) are tested. All of the specimens experienced a brittle failure mode. The 45°-angled specimens provide a more secure interlocking mechanism compared to the 60°-angled specimens. Overall, fiber-parallel 60°-angled specimens have the highest yield and ultimate strengths. Increasing the insertion angle from 45° to 60° decreases the ductility and slip modulus. Changing the fiber orientation from parallel to perpendicular does not have a significant effect on the slip modulus and ductility, however, there is a decrease in the yield and ultimate strengths. Finally, based on the overall results from the experiments, the joints are classified as having low ductility.

The seismic and lateral resistance of column-and-tie wooden buildings was studied in this research. A simple mortise and tenon side joint model and an overall framework model were establish...

Background : Research actuality is determined by the first, the prevalence of refraction errors including progressive myopia among children secondly, high risk and tends to develop complications from the visual organ in refractive disorders. Aims : To investigate tissue reactions occurring in the Tenon’s capsule with anomalies of refraction, including with progressive myopia. Materials and methods : A one-step study of the Tenon’s capsule of 47 samples (25 with hyperopia and 22 with progressive myopia) was carried out. The material of the Tenon’s capsule was obtained during surgical treatment of strabismus and sclera strengthening operations with progressive myopia. The Tenon’s capsule was studied at different levels: tissue, cellular, subcellular. Fragments of Tenon’s capsule were stained with hematoxylin-eosin and picrofuchsin mixture by the method of van Gieson at the tissue level. This allowed obtaining a general picture of the morphology of Tenon’s capsule. Fragments of Tenon’s capsule were stained by toluidine blue in tetraborate sodium at the cellular level. This gave the opportunity to define the scope for ultratome and spend morphometry of cellular composition. A fragment of Tenon’s capsule was studied by transmission electron microscopy (TEM) at the subcellular level and was performed ultrastructural morphometry of fibroblasts, evaluation of the density of the collagen fibers. Results : Were evaluated by qualitative and quantitative characteristics of the structure of Tenon’s capsule with two anomalies of refractions: progressive myopia and hyperopia: with progressive myopia in Tenon’s capsule, in contrast to hyperopia, the following number of fibroblasts (1.56±0.12 per 10 4 µm 2 ), mast cells (0.08±0.0 2 per 10 4 µm2), adipocytes (0.01±0.001 per 10 4 µm 2 ) were observed; ultrastructural features of fibroblasts were represented by such quantitative characteristics: the area of the fibroblast nucleus was 1.60±0.82 in µm 2 , the length of the karyolemma was 6.99±0.189 µm, the number of nucleoli was 0.17±0.015 per 1 µm 2 , the number of mitochondria and lysosome -2.05±0.14 per 1 µm2; 0.64±0.08 per 1 µm 2 , respectively); the density of collagen fiber was 28.72±4.18%, fibrillar fibrillation and fragmentation were recorded. Conclusions: Hyperplasia of fibroblasts and their ultrastructures, mast cells, reduction in the level of adipocytes and the density of collagen fibrils ― these changes are features of the tissue reaction in the tenon capsule and reflect the adaptive nature of the processes occurring during progressive myopia.

The working capacity of the logging and wood processing equipment feeding mechanisms is determined by the achievable coupling of the roller’s working elements with the movable blanks. The coupling stability depends significantly on the geometry specified in the design and implemented in manufacturing and physicochemical properties of the materials of tenons that capture, hold and continuously move the blanks into the processing zone. During operation, the geometrical parameters of tenons are changing due to wearing out, which is a result of a complex set of mechanical, chemical, thermal and other influences that accompany friction and deformation interaction of working elements of feeders and movable wood. Worn down tenons do not provide reliable movement of a blank, due to its slippage, which causes quality reduction of final products and leads to intensification of the cutting tool wearing out. At the same time the features of influence of tenon geometrical form on the mating forces of feeding rollers with movable blanks in conditions of development of the tribotechnical characteristics, which provide their working capacity, are not studied sufficiently for the practical use. Therefore, the research purpose is to clarify the conditions of friction-mechanical interaction of working elements of rollers with wood and to identify patterns of wearing out of tenon working surfaces, which allows theoretically substantiate their rational geometrical shape and requirements for the physicochemical characteristics of recommended materials. The acting load’s principles realized in the zone of contact of the metal surfaces of tenons with wood at displacement of blanks are considered for these purposes. The process of the force interaction change of tenons with blanks is shown beginning with the moment of contact of a certain tenon until it leaves the coupling. Its analysis showed that already at the beginning of the contact the shock bending load begins to act on the top of a tenon. The load in case of peak values often leads to wearing out by crumbling sufficiently large microvolumes of the feeding tenons. The probability of development of such fracture pattern is the greatest with insufficient strength of the using material and pre-sence of structural defects, especially unfavorably located microcracks, and the action of dangerous tensile residual stresses. These factors also significantly affect the corrosion-mechanical wearing out of the working surfaces of tenons and their resistance movement in wood. Thus, the main factor of effective transportation of a blank to the processing zone and achievement of high wearing resistance of feeding rollers is optimization the tenon geometry, properties of the assigned materials and technology of strengthening treatment of the concerned details. For citation: Pamfilov E.A., Pilyushina G.A., Sheveleva E.V., Prozorov Ya.S., Pyrikov P.G. Improving the Feeder’s Working Capacity of Timber Processing Equipment. Lesnoy Zhurnal [Forestry Journal], 2019, no. 2, pp. 102–110. DOI: 10.17238/issn0536-1036.2019.2.102

Introduction Despite the wide prevalence of ankle fractures, no consensus exists on the most accurate radiologic diagnostic tool to indicate medial ligament injury in isolated type B distal fibular fractures. The aim of this study was to evaluate the value of the fibular fracture displacement in predicting medial clear space widening on the gravity stress radiographs, as a parameter of fracture instability. Methods This retrospective cohort study included 192 patients with an isolated type B fibular fracture, for which a regular mortise and gravity stress radiograph were made in our hospital between January 2014 and December 2019. On the regular mortise and lateral radiographs, the medial clear space (MCS), superior clear space (SCS), anteroposterior and lateral fibular displacement were measured. On the gravity stress radiograph, the MCS and SCS were measured. Instability was defined as MCS >= SCS + 3.0 mm on the gravity stress radiograph. A receiver operating characteristic (ROC) curve was constructed to evaluate the predictive value of the fibular displacement. Results Of the 192 included patients, 55 (29%) patients had instable ankle fractures. In predicting instability, fibular displacement demonstrated an area under the curve (AUC) of 0.68 (95% confidence interval 0.60-0.77) and a correlation coefficient of 0.41 with MCS. Conclusion Fibular displacement on regular mortise view is a poor predictor of instability in type B fibular fractures. It should not be advised to use the fracture displacement as parameter for medial injury and thus for operative treatment.

The facade of the old school is registered in the list of cultural monuments and located in the conservation zone of the urban monument reservation. Due to the construction of a new building, it was necessary to reinforce and structurally support (by means of an anchored reinforced concrete wall) the south wing of the old section of the school. No fissures were allowed to develop because they could damage the valuable art nouveau facades. Therefore, great emphasis was given to the technological and structural design of the reinforced concrete gunite wall. Precise geodetic measurements confirmed that the decline of the south wing of the school of the gunite wall was minimum, specifically 1,5 mm, after the completion. No cracks appeared. The building won first place in the “Building of the South Moravian Region” competition in 2018 in the category of public utilities in the Czech Republic – see www.gero.cz.

Chinese traditional wooden structure toys have a long history, and the way of unlocking them is exquisite and ingenious, but they are gradually vanished from modern society, therefore it is necessary to redesign them intelligently. Based on embodied cognition theory, this paper analyzes the contact points of users when using products in specific use scenarios, and explores the design possibility of traditional wooden toys. This design case takes the pagoda shaped wooden board and mortise and tenon blocks of different materials and colors as the main body of the product, with sensors and Arduino circuit boards inside, which are connected to the mobile terminal of the tablet computer to provide help and record the user history of toys. The purpose of this research is to make the traditional wooden toys adapt to the modern society through redesign.