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Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT [AR] أصالة استخدام مفصلات ذيل الحمامة في السفن المصرية القديمة شهدت الحضارة الفرعونية تنوعًا في صناعة السفن طبقاً للوسط المائي الذي أبحرت فيه السفينة سواء نهر النيل أو البحرين الأحمر والمتوسط، بالإضافة إلى المسطحات المائية مثل البحيرات والقنوات. كان لبناة السفن خصائص خاصة في طرق ربط وتجميع ألواح المراكب، إحداها تُسمى ذيل الحمامة. على الرغم من ظهور طريقة ذيل الحمامة في الاثاث والتوابيت المصرية القديمة في العصور المبكرة، إلا أنها ظهرت لأول مرة في صناعة السفن فى الدولة الوسطى فى سفن دهشور، والتي كثر الجدل بين العلماء حول ماهية استخدام تقنية مفصلات ذيل الحمامة بالدُسرة أم بالخياطة في تلك السفن، حيث اختلفت أراء العلماء حول أصلية استخدام هذه التقنية؛ بعضهم يعتقد إن ذيل الحمامة استُخدم مع الخياطة وأن ما يوجد في الوقت الحاضر من دسُر ما هو إلا تجديد أَضيف بعد اكتشاف السفن في أوائل القرن الماضي عوضاً عن الخياطة، والبعض الأخر يعتقد أنه استُخدم مع الدسُر منذ القدم. مع مطلع القرن الحادي والعشرون، اكتشف علماء الآثار البحرية ألواح سفن تعود إلى فترة الدولة الوسطى في كهوف مرسى وادي جواسيس على ساحل البحر الأحمر، وعلى أحد هذه الألواح ظهرت نقر مفصلات ذيل الحمامة. تناقش هذه الورقة البحثية ماهية طريقة ذيل الحمامة في ربط ألواح السفن وأهميتها، وتستعرض اختلافات آراء العلماء حول استخدامها مع الخياطة أم الدسُرة، وتقديم ملاحظة الباحث التي تؤكد وتُحسم الجدل حول استخدام تلك المفصل مع الخياطة ام الدسُرة في سفن دهشور اعتماداً على مقارنتها بما ظهر في ألواح السفن من مرسى وادي جواسيس. [EN] Ancient Egyptian civilization experienced a variety of ships designed for different bodies of water, including the Mediterranean, the Red Sea, and the Nile River, as well as lakes and canals. Shipbuilders used special fastening methods to assemble their ships, such as the use of dovetail joints. While the dovetail technique was applied in ancient Egyptian furniture and coffins, it was first observed in the Egyptian shipbuilding of Dahshur boats in the Middle Kingdom. The antiquity of dovetail joints with ligatures or tenons in Dahshur boats has long been debated by archaeologists. Thus, different theories have been presented on the originality of using dovetail mortise with ligatures or tenons. Some authors believed that it was originally used with ligatures, but tenons were modified after the boats' discovery in the early 20th century, while others argued that it was used with tenons from ancient times. In the early 21st century, archaeologists discovered the dovetail technique in ship timber at Mersa / Wadi Gawasis on the Red Sea, dating back to the Middle Kingdom. This paper aims to explore the significance of the dovetail technique in ancient Egyptian shipbuilding, as well as the various theories on its use with tenons or ligatures. It presents the author’s analysis and observation to resolve the controversy about its use in Dahshur boats, based on a comparison with the ship timbers of Wadi Gawasis.

To observe the surgical outcome of "Tenon Excision with Fibrin Glue-Assisted Reattachment of Conjunctiva Flap" (T.E.F.A.R.C.) for the treatment of symptomatic conjunctivochalasis (CCH). This is a retrospective case series of CCH patients undergoing T.E.F.A.R.C. from January 2017 to December 2020 were reviewed. Seven patients (14 eyes) with symptomatic CCH received T.E.F.A.R.C. in both eyes. The symptoms before and after the procedures were compared and surgical complication was evaluated. The mean follow-up time was 13.7 ± 2.14 months. After the operation, resolution of the symptoms was reported in 12 eyes (86%). The grade of CCH decreased from 3 to 0 in all 14 eyes, and the restoration of inferior conjunctival surface and fornix within 1 day was also observed in all eyes. Most patients had localized injection and mild chemosis after the operation, which mostly recovered within 3 weeks. No complication or recurrence of CCH was reported after 1 year of follow-up. In conclusion, T.E.F.A.R.C. is a simple and effective treatment option for CCH with less surgical complication. Future larger studies are needed to confirm its clinical applicability. [ABSTRACT FROM AUTHOR]

A systematic research on the fracture failure of the tenon of X20Cr13 blade has been carried out. This research consists of two parts: comprehensive analysis and simulation analysis. The fretting wear produces the failure source which leads to the occurrence and development of cracks. M23C6 carbides damage the continuity of matrix structure and create conditions for the initiation and propagation of cracks. The simulation analysis further confirmed that the stress at the root of blade tenon is too large and the possibility of failure caused by resonance is eliminated. Some constructive suggestions are put forward for this engineering problem. [ABSTRACT FROM AUTHOR]

Glaucoma treatment options as well as its etiology are far from understood. Gene expression (transcriptomics) data of the anterior segment of the eye can help by elucidating the molecular-mechanistic underpinnings, and we present an up-to-date description and discussion of what gene expression data are publicly available, and for which purposes these can be used. We feature the few resources covering all segments of the eye, and we then specifically focus on the anterior segment, and provide an extensive list of the Gene Expression Omnibus data that may be useful. We also feature single-cell data of relevance, particularly three datasets from tissues of relevance to aqueous humor outflow. We describe how the data have been used by researchers, by following up resource citations and data re-analyses. We discuss datasets and analyses pertaining to fibrosis following glaucoma surgery, and to glaucoma resulting from the use of steroids. We conclude by pointing out the current lack and underutilization of ocular gene expression data, and how the state of the art is expected to improve in the future. [ABSTRACT FROM AUTHOR]

Glaucoma treatment options as well as its etiology are far from understood. Gene expression (transcriptomics) data of the anterior segment of the eye can help by elucidating the molecular-mechanistic underpinnings, and we present an up-to-date description and discussion of what gene expression data are publicly available, and for which purposes these can be used. We feature the few resources covering all segments of the eye, and we then specifically focus on the anterior segment, and provide an extensive list of the Gene Expression Omnibus data that may be useful. We also feature single-cell data of relevance, particularly three datasets from tissues of relevance to aqueous humor outflow. We describe how the data have been used by researchers, by following up resource citations and data re-analyses. We discuss datasets and analyses pertaining to fibrosis following glaucoma surgery, and to glaucoma resulting from the use of steroids. We conclude by pointing out the current lack and underutilization of ocular gene expression data, and how the state of the art is expected to improve in the future.

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using finite element method (FEM) has become wide spread in the field of wood mechanics for analyzing difficult problems instead of conventional methods. The objective of this study is to determine the strength properties of wood corner joints using FEM. For this purpose, diagonal compression and diagonal tension experiments were carried out using dowel, mortise and tenon elements. Corner joints (L-type) were prepared with Scotch pine (Pinus sylvestris L.) and Beech (Fagus orientalis Lipsky) woods. Data obtained experimentally were used in FEM computer modeling to determine structural specifi cations of wood materials. The amount of deformation as a result of compression-tension in the corner joints was determined and then simulated with a computer program using FEM (ANSYS Multiphysics/LS-DYNA). As a result, the amount of deformation obtained from experiments was consistent with the FEM computer modeling with 90 to 97 %. It is suggested that strength properties of joints can be forecast by using FEM computer modeling instead of physical experiments that may cause loss of time, increase of cost and destruction of materials.

This study reports the moment resistance, stiffness, and numerical analysis of various sizes of round-end mortise and tenon joints. L-shaped and T-shaped specimens were constructed. Joints were manufactured using three tenon widths and three tenon lengths with 10 replications for each combination. Specimens were constructed of Turkish beech, and the joints were assembled with polyvinylacetate (PVAc) adhesive. Bending tests were carried out in compliance with accepted test methods. Numerical analyses were performed with finite element method (FEM) software. At the end of the study, the joints became stronger and stiffer as either tenon width or length increased. Tenon length had a more significant effect on moment resistance, while tenon width had a more significant effect on stiffness. Ultimate moment resistances were obtained with L-shaped joint construction of 50 × 50 mm tenons and T-shaped joint construction of 40 × 50 mm tenons. Strength of a chair could be increased by considering these results in engineering design process. Results showed that the numerical analyses gave reasonable estimates of mechanical behavior of joints. Analytical calculations and numerical simulations confirmed that the maximum stress in the glue line was concentrated at the edge and corners, and that the modeled joints had a shape-adhesive nature.

The present paper focuses on construction of school seats for developing countries from locally available resources using the local industry and low-end technology. Aim of the work is experimental assessment of mechanical properties of joints flexion in angular plane. Furthermore work considers assessment of joint firmness and comparison between various joint types. Paper encloses the review of various joint manufacturing designs (tenon and mortise), which were proposed for its suitable mechanical properties and simplicity of manufacturing. Designated joint type is easiest form of joint construction and technologically feasible for chair manufacturing. The joints were constructed from fir wood. Further the work introduces design of simple seat construction made from massive wood material manufactured by low-end technology with regards to achieving the due specifications. The task of this work is to design the viable manufacturing process of seats and chairs from raw wood and scrap material. Essential part of work is also manufacturing of seat prototype and simplified model of proposed mortise and tenon drill.

To observe the surgical outcome of "Tenon Excision with Fibrin Glue-Assisted Reattachment of Conjunctiva Flap" (T.E.F.A.R.C.) for the treatment of symptomatic conjunctivochalasis (CCH). This is a retrospective case series of CCH patients undergoing T.E.F.A.R.C. from January 2017 to December 2020 were reviewed. Seven patients (14 eyes) with symptomatic CCH received T.E.F.A.R.C. in both eyes. The symptoms before and after the procedures were compared and surgical complication was evaluated. The mean follow-up time was 13.7 ± 2.14 months. After the operation, resolution of the symptoms was reported in 12 eyes (86%). The grade of CCH decreased from 3 to 0 in all 14 eyes, and the restoration of inferior conjunctival surface and fornix within 1 day was also observed in all eyes. Most patients had localized injection and mild chemosis after the operation, which mostly recovered within 3 weeks. No complication or recurrence of CCH was reported after 1 year of follow-up. In conclusion, T.E.F.A.R.C. is a simple and effective treatment option for CCH with less surgical complication. Future larger studies are needed to confirm its clinical applicability., Competing Interests: Dr. Wei-Li Chen, an editorial board member at Taiwan Journal of Ophthalmology, had no role in the peer review process of or decision to publish this article. The other authors declared no conflicts of interest in writing this paper., (Copyright: © 2023 Taiwan J Ophthalmol.)

This study reports the moment resistance, stiffness, and numerical analysis of various sizes of round-end mortise and tenon joints. L-shaped and T-shaped specimens were constructed. Joints were manufactured using three tenon widths and three tenon lengths with 10 replications for each combination. Specimens were constructed of Turkish beech, and the joints were assembled with polyvinylacetate (PVAc) adhesive. Bending tests were carried out in compliance with accepted test methods. Numerical analyses were performed with finite element method (FEM) software. At the end of the study, the joints became stronger and stiffer as either tenon width or length increased. Tenon length had a more significant effect on moment resistance, while tenon width had a more significant effect on stiffness. Ultimate moment resistances were obtained with Lshaped joint construction of 50 × 50 mm tenons and T-shaped joint construction of 40 × 50 mm tenons. Strength of a chair could be increased by considering these results in engineering design process. Results showed that the numerical analyses gave reasonable estimates of mechanical behavior of joints. Analytical calculations and numerical simulations confirmed that the maximum stress in the glue line was concentrated at the edge and corners, and that the modeled joints had a shape-adhesive nature. [ABSTRACT FROM AUTHOR]

Copyright of Wood Industry / Drvna Industrija is the property of Drvna Industrija and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Keyed-through tenon (KTT) joints are timber frame joints consisting of a key placed through the tenon, creating bearing against the back side of the mortise. This joint allows greater flexibility in key sizing compared with typical pegged mortise and tenon joints. However, no experimental testing is available to estimate the strength capacity of these joints. This paper measured the strength and stiffness of KTT joints considering differences in wood species, protruding tenon length, and number of keys. A tensile load was applied to a KTT joint similar to previous testing conducted on pegged mortise and tenon joints. Shorter tenon lengths produced brittle failures of the tenon, whereas longer tenon lengths produced ductile bending and crushing of the keys. Yield load values using the 5% offset method could not be determined for the shorter tenon length samples, but the ultimate load values could be used for yield load. Two keys were approximately twice as strong as a single key because of the increased bearing area and the number of tenon shear planes for load transfer. KTT joints with two keys and 11-in. (279-mm) protruding tenons were recommended from this experimental study. Results of KTT joints compared with previously tested pegged mortise and tenon joints with two 1-in. (25-mm) diameter pegs demonstrated that KTT joints with two keys produced stiffer and stronger joints with maximum load values 41% greater than previously tested pegged joints of similar composition. Size limitations and protection of the protruding tenon from damage are important considerations in the design of KTT joints in structures. [ABSTRACT FROM AUTHOR]

Existing heritage wooden structures in China have a common structural component which composes of layers of wooden beam to resist the vertical applied load. The performance of this type of component under load is not clear particularly under the seismic effect. This paper presents a nonlinear analytical model of a two-layer wooden beam system based on Euler–Bernoulli beam theory. The proposed model takes into account the effect of the friction–slip–shear between the two individual layers with a specified range of slip. There are four deformation scenarios to provide the load resistance based on the state of friction between the two layers and the state of shear at the connector (tenon). The behavior of the tenon with the friction–slip–shear mechanism is significant to the mechanical behavior of the two-layer beam system. This analytical study aims at evaluating the frictional stiffness of a two-layer wooden beam, and an implicit formulation on the frictional stiffness of the system is presented. Its effect on the lateral deformation when subjected to four kinds of loadings is studied. The hysteresis curve is then plotted for different kinds of pseudo-dynamic external loads to illustrate the energy dissipation capacity of this type of joint in Tibetan structures. [ABSTRACT FROM AUTHOR]

Chinese ancient timber structures are famous worldwide. They are connected with unique joints known as mortise and tenon. Since few studies have addressed the structure of these joints, preserving these structures is difficult. Recent studies based on one kind of joint—the wedged reported its semi-rigid property; however, many more different joints remain to be studied. The present study is based on experiments of 26 wood pieces, five different wood joints, and 13 different crafts. These different joints were widely used in many regions of China. Some data of joints under vertical and horizontal loadings have been recorded. A model based on experimental data was built and can be widely applied in other studies. Three traditional Chinese wood structures were compared and analyzed with experimental data. The reasons and differences of these structures were concluded. Taking all these findings into consideration, the present study aims to be an important help to the protection of current Chinese wood heritages. [ABSTRACT FROM PUBLISHER]

The occlusal forces applied to a fixed partial denture are transmitted to the supporting structures through the pontic, connectors and retainer. Rigid connectors between pontics are preferred way of fabricating most fixed partial dentures as they provide desirable strength and stability to the prosthesis. But it has been theorized that forces are transmitted to the terminal retainers are as a result of the middle abutment acting as a fulcrum, causing failure of the weaker retainer. It has also been suggested that the intrusion of the abutments under the loading could lead to failure between any retainer and its respective abutment. To reduce this hazard, the use of nonrigid connector has been recommended as it acts as broken-stress mechanical union of retainer and pontic, instead of usual rigid connector. [ABSTRACT FROM AUTHOR]