Then, each group was divided into 4 sub-groups according to priming and cement used (n  = 20 each): conventional self-adhesive resin cement, MDP-silane Primer, MDP primer both with conventional self-adhesive resin cement, and MDP contained cement. Shear bond strength (SBS) was measured after thermocycling. Failure mode was analyzed using stereomicroscope. Contact angle and surface topography were investigated using other fully sintered samples (n  = 30) constructed for that sole purpose, divided into control . Two-way ANOVA was performed for SBS and failure mode was analyzed. The use of Alumina-sandblasting showed higher SBS compared to Glass-bead pre-treatment for MDP-silane primer (p = 0.034) and MDP primer (p < 0.001). While MDP contained cement showed higher but insignificant SBS when pre-treated with glass-beads. Alumina-sandblasting and glass-bead pre-treatments improve bond strength of zirconia combined using primers before cementation with conventional resin cement. Also, self-adhesive MDP contained cement along with surface pre-treatment showed the highest achievable bond strength. It was concluded that both alumina-sandblasting and glass-bead blasting improved SBS combined with MDP containing self-adhesive resin cement reducing the required clinical steps during cementation of zirconia restorations.In fact, bonding of zirconia restorations is still a big challenge in clinical situations and many bonding protocols discussed in literature might be still controversial. The aim of this was to study assess the bond strength of zirconia after alumina and glass-bead pre-treatments with two different primers in combination with conventional resin cement and 10-methacryloyloxydecyl dihydrogen phosphate (MDP) containing self-adhesive resin cement without priming. Fully sintered high translucent zirconia samples ( That leads to increase the range of indications in the field of fixed prosthodontics and indirect restorations, but earlier zirconia generations suffered from lower translucency, higher opacity and hence, less superior esthetics as it is composed of dense polycrystalline structure with no glass matrix when compared to glass ceramics limiting its use to posterior region2. To improve the optical properties, increasing the yttria content to 5 mol% yttria-stabilized tetragonal zirconia polycrystals (5Y-TZP) resulting in 50% cubic phase compared to conventional 3 mol% yttria stabilized tetragonal zirconia5 thus improving the overall aesthetics and resulted in the introduction of new class of ultra-translucent zirconia.Nowadays, the demand for highly esthetic restorations is increasing in everyday dental practice owing to the fast-paced evolvement and innovation in digital dentistry. Dental zirconia is considered one of the most commonly used restorative materials due to its high mechanical properties compared to glass ceramics6. The incidence of loss of retention for zirconia restorations was 4.7% over the 5-year observation period7, and it is the directly caused by the deboning between the various adhesive interfaces within that structure8.The bonding of zirconia to tooth tissues or other synthetic materials is controversial when compared to silica-based ceramic material due to its chemical inertness and resistance to aggressive chemical agents  molecule and its salt were proposed to alter the zirconia surface chemistry17.There are many ways for increasing the bond strength between zirconia ceramic and resin cement had been investigated in literature, either mechanical, chemical, and/or chemico-mechanical surface pre-treatment methods18. However, that alumina air abrasion produces surface defects such as flaws, plastic deformation, embedded abrasive alumina, and microcracks, which can compromise the mechanical properties of zirconia and decrease fracture strength19. To decrease the defect to zirconia surface, the use of glass beads as a softer material than sharp and hard alumina was suggested by Khanlar et al., in 2022, followed by 10-MDP & silane primer which reported a desirable bonding performance without creating surface microcracks on zirconia20.The air abrasion method with alumina particles showed the highest bond strength in comparison with other surface conditioning methodsThere are scarce reports on the effect of glass-beads blasting as a mechanical bonding method either alone or combined chemically with different zirconia primers. Hence, this in vitro study was conducted to evaluate the effect of alumina-sandblasting and glass-bead blasting on bond strength of high translucent (5Y-TZP) zirconia solely or combined with different formulations of zirconia primers and MDP contained self-adhesive resin cement without subsequent priming. The null hypotheses tested were that 1. sandblasted zirconia either with alumina- and/or glass-beads will show similar bond strength, 2. different MDP-primers will not affect the bond strength to zirconia 3. MDP containing self-adhesive resin cement will show a similar result to other MDP-primers tested.The tested substrate is a high translucent yttria-stabilized tetragonal zirconia polycrystals specimens . An MDP-Silane primer  and an MDP-BPDM primer  were used. For cementation, conventional resin cement  and self-adhesive resin cement  were used in the current study. The full compositions of used materials are listed in Table A total of 160 squares samples of 5Y-PSZ (10 × 10 × 3 mm before sintering) using a low-speed precision saw machine  in a dry condition without water coolant. Another 160 disc shaped samples of a 4 mm dimeter and 3 mm thickness were used to be cemented to each other for shear bond strength evaluation. For surface roughness and contact angle measurements, another 30 square samples with previously mentioned dimensions were utilized. All samples were sintered utilizing a 7-stages cycle at 1450℃ following the manufacturer instruction in zirconia furnace . Sintering process parameters are listed in Table n = 160 each)] were divided equally into two groups according to the pre-treatment protocol (n  = 80 each); Alumina-sandblasting (AB) and Glass-beads (GB) groups. Each group was further sub-divided into 4 sub-groups according to the cementation protocol (n  = 20 each); 1. no priming + conventional resin cement, 2. MDP-silane primer + conventional resin cement, 3. MDP-BPDM primer + conventional resin cement and 4. MDP containing resin cement without subsequent priming. A graphical presentation of the methodology is presented in Fig. For shear bond strength analysis, the fully sintered samples [both square and disc shaped n = 60 each] 2O3  and 75 µm Glass-beads particles respectively. The blasting time for both groups were 20 s at a pressure of 25 psi at a 10 mm distance and 90° angle using a sandblasting device . Afterwards, all samples were cleaned using ultrasonic cleaner  filled with distilled water for two minutes and then completely dried with oil-free air.A 600-grit silicon carbide paper was used to polish all samples before cementation. AB and GB groups were blasted with 50 µm Al12 and cement curing were initiated using LED light with a curing intensity of 1500 mW /cm2  for 40 s.Each large square-shaped sample was bonded to the smaller disc-shaped sample. For the conventional resin cement groups, a dual cured resin cement  was applied after alumina & glass-beads sandblasting respective to each group with no prior priming. For MDP-silane primer group: MDP-Silane primer  was applied by a micro-brush and left to dry for 60 s and air dried, then conventional resin cement was applied. For MDP-BPDM primer groups, samples were primed with 2 coats of MDP-BPDM primer  for 5 s then gentle air jet was applied followed by conventional resin cement. For MDP-containing self-adhesive resin cement group, all samples were cemented with dual-cured MDP-containing self-adhesive resin cement  with no prior priming. A static standard load of 5 kg was applied to all samples during cementation with the aid of a loading device13. A universal testing machine  was used to measure and record the shear bond strength values with a crosshead speed of 1 mm/min. For the mode of failure analysis, a stereomicroscope  was used at a magnification of 20 × to examine the de-bonded interface and failure was categorized as; adhesive failure “A”, cohesive failure “C” and mixed failure “M”.All samples were aged by the aid of a thermocycler  to induce hydro-thermal stresses within the tested material and the cement interface. The bonded samples were subjected to 10,000 cycles by immersing in distilled water bath of 5 °C and 55 °C with a dwell time of 20 s and a lag time of 10 s simulating one year of clinical service in the oral cavityn = 10 each), into control group , Alumina-sandblasting (AB) and Glass-beads (GB).The samples were analyzed using a 3D confocal laser scanning microscope  with a 50 × magnification (scanning area 205 × 273.3 μm) and a MultiFile Analyzer software  was used to analyze obtained scans. Arithmetical mean height (Sa), developed interfacial area ratio (Sdr) and texture aspect ratio (Str) values were recorded and analyzed.For surface roughness, 30 square fully sintered samples were divided into 3 groups according to type of pre-treatment . For each sample, 3 readings were recorded for 3 different drops and the average value was considered the mean reading for every tested sample. All mean values were reported for statistical analysis.20. A minimum of 20 samples in each group will be sufficient to detect a power of 95% when α = 0.05. The mean for control was 9.2 and for AB was 11.7 with a standard deviation equals to 2 resulted in an effect size (d) of 1.2. Sample size was calculated using G*Power version 3.1.9. Data explored for normality using Shapiro–Wilk test. Two-way ANOVA used to compare between tested pre-treatment and primer/cement followed by Tukey’s HSD test for pairwise comparison. Additional, shear bond strength data were analyzed using Weibull analysis . Weibull parameters were calculated using Wald estimation, and 95% confidence intervals were calculated with Monte Carlo simulations. The different groups were compared at the characteristic strength (63.2% and 10% probability of failure). For surface roughness parameters and contact angle measurements, one-way ANOVA used to compare between tested groups followed by Tukey’s HSD test for pairwise comparison. (α = 0.05). Statistical analysis was performed with IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp.Sample size was calculated based on data extracted from Khanlar et. al. 2022p = 0.003 and p < 0.001, respectively. The interaction between both variables resulted in a significant effect on shear bond strength at p = 0.002 as shown in Table p = 0.034) and MDP-BPDM (p < 0.001) groups. While for both conventional resin cement groups and MDP containing self-adhesive resin cement showed insignificant difference when pre-treated with AB and GB. For AB pre-treated groups, conventional resin cement showed the lowest significant shear bond strength compared to all other groups and insignificant difference resulted between MDP-silane primer, MDP-BPDM primer, and MDP containing cement. For GB pre-treated groups, conventional resin cement showed the lowest significant shear bond strength and MDP containing resin cement showed the highest shear bond strength compared to all other groups. Insignificant difference between MDP-silane primer and MDP-BPDM primer. Shear bond strength values for different tested groups are presented in Table Pre-treatment and primer/cement groups resulted in significant effect on shear bond strength at Weibull analysis results presented in Table For glass beads (GB) pre-treatment, all the tested groups showed 100% adhesive failure. While for alumina sandblasting (AB) pre-treatment, all groups showed both mixed failure and adhesive failure. No group showed cohesive failure for both GB and AB. The mode of failure analysis is represented in Fig. p < 0.001. While for Sdr, Control group (1.20 ± 0.11) and AB (1.36 ± 0.70) showed the highest significant Sdr values compared GB (0.74 ± 0.14) at p < 0.001. For Str, Control group (0.85 ± 0.03) showed the lowest significant str values compared AB (0.77 ± 0.10) at p = 0.044. GB (0.79 ± 0.07) showed insignificant difference with both control and AB for Str values. Contact angle measurements showed that control group (50.53 ± 4.29) had the highest significant values compared AB (44.94 ± 2.12) at p = 0.038. GB (47.60 ± 2.34) showed insignificant difference with both control and AB for contact angle measurement.Results of surface roughness parameters and contact angle are presented in Fig. Over the last decades zirconia was introduced in dentistry to be used as a stronger alternative replacing weaker silica-based ceramics and increasing the range of its indications as a restorative alternative. However, bonding to zirconia has always been a major problem even with the development of more translucent monolithic alternatives since most of bonding protocols are based upon bonding to the glass matrix that can be eroded by the effect of a strong acid which is not the case with zirconia as it lacks the presence of the glassy matrix due to its polycrystalline nature.This study investigated the bond strength to zirconia after alumina and glass-bead blasting with two different MDP-primers in combination with conventional resin cement, in addition to an MDP containing self-adhesive resin cement without priming. The tested null hypotheses were rejected as alumina- and glass-beads sandblasting combined with priming before cementation and MDP contained cement used solely showed higher bond strength when compared to sandblasted groups that were cemented with conventional resin cement with no priming.21.The bond strength created between zirconia and the adhesive cement plays a major role in the success and longevity of dental restorations. A weak adhesion might be a major cause in crack formation in the restorative material that may reach the cement interface causing failure of a restoration23. As for glass-beads the increase of bond strength may be attributed to the incorporation of silica to the bonded surface resulting in stable chemical bonds between the hydroxyl groups (OH) of the silica of the glass surface and the primer/resin cement24. Another study evaluated the effect of different silicatization protocols  with various silane treatment methods on bond strength of translucent zirconia and they found that both alumina and glass-beads air blasting improved bond strength. Their finding was supported by Energy Dispersive Spectroscopy (EDS) and X-ray Photoelectron Spectroscopy (XPS)analysis which confirmed the deposition high silica content at the surface of cemented samples even that was not washed out by ethanol or ultrasonic cleaning10.The results of this study revealed that alumina or glass-beads sandblasting combined with chemical surface treatments (primer) resulted in a significant increase in shear bond strength of 5Y-PSZ zirconia. In previous studies, it was found that air abrasion with alumina particles is the most preferred and reliable surface treatment method for high strength ceramics as it increases surface roughness resulting in an in-creased surface energy, improving wettability, and may decontaminate bonding surfaces20, who revealed that air abrasion with alumina particles had an effect of increasing the surface roughness while glass-beads had no effect. Moreover, their SEM/EDS investigations found that alumina created grooves and surface flowers while glass-beads resulted in the deposition of silica particles without affecting the surface roughness20. On the other hand, Mehari et al.25, found that alumina increased the bond strength while glass-beads and no treatment showed almost the same results for three different types of zirconia which may be attributed to the increased surface roughness to alumina blasted surface.Surface roughness of the cemented zirconia may play a role in the adhesion as it may increase surface area of the cemented substrate. The surface roughness after alumina-blasting was higher compared to glass-beads blasted surface. The findings of this study were in agreement with Khanlar et al.26. Moreover, alumina sandblasting led to formation of micro-mechanical means in terms of increased roughness enhancing surface energy and more resin flow in those micro-retentive features resulting in higher bond strength27. In previous studies, it was suggested that sandblasting may be responsible for generating hydroxyl groups on the zirconia surfaces, leading to the increase of zirconia reactivity with phosphate monomers in MDP affecting bond strength29. This was not the situation with glass-beads, as the low hardness nature of glass-bead cannot alter surface roughness of zirconia. Instead, its effect was limited embedding the surface of zirconia with silica particles resulting in decreased contact angle and enhanced surface energy which improve the bonding20.Alumina sandblasting showed the lowest significant contact angle and the highest surface roughness when compared to glass-beads and control group, both factors that led to high bond strength as per outcomes of our study. Translucent zirconia has larger grains size resulting in grains being pulled out readily during the alumina sandblasting causing surface defects and in succession increased zirconia surface roughness16. However, Pure-MDP primers are not available in the market and the commercially available primers combine more than one primer for universal application and compatibility with various substrates.The results of this study regardless of the pre-treatment method showed that MDP containing self-adhesive resin cement had the highest bond strength regardless of the pre-treatment method utilized followed by MDP-BPDM primer followed by MDP-silane primer for alumina air abrasion. As for groups with glass-beads pre-treatment, MDP-silane and MDP-BPDM containing primers had a similar bond strength value. Pure MDP results in better bonding performance to zirconia surface and addition of silane in one-bottle with MDP can decrease the bonding30. MDP containing primers has a hydrophobic phosphoric group that reacts with the hydroxyl groups on the surface of the translucent zirconia enhancing bond strength31. Additionally, MDP prevents the penetration of water between the hydrophobic phosphate layer and the oxide layer of zirconia by the action of decyl group in MDP32.The phosphate easter groups in the MDP molecule in theory react with one or two zirconium atoms, forming two bonding configurations either “double coordinate” or “single coordinate”33. This may be attributed to the fact that MDP contains both a polymerizable methacrylate terminal end that adheres to resin and a hydrophilic phosphate terminal end that chemically adheres to zirconia enhancing the bond strength21.According to the literature, the presence of MDP in the resin luting agent forms a stable bond to airborne pre-treated zirconia even after thermocycling35. Also, with GB group the higher bond strength values are justified by chemical interaction between the silane and silica from the glass beads remaining on the zirconia surface20. However, the bond strength was lower than that of MDP containing self-adhesive resin cement. This may be attributed to silanols in the MDP-silane containing primer, which may result in that decrease in bond strength between MDP and zirconia surface36.The use of MDP-silane containing primer increased the bond strength between resin cement and zirconia ceramics as per findings in previous studies39. A previous study disagreed with our study finding, attributing the reason to the presence of carboxylic acid monomer in BPDM that may have a determinantal effect on the connection between this primer and self-adhesive resin cement methacrylate40.In previous studies, it was found that MDP-BPDM containing primer had a positive effect on bond strength of cemented zirconiaThus, based on that study the use of alumina air abrasion was always considered as the golden standard for bonding to zirconia, it worthy to mention that glass-beads can offer a promising alternative to enhance bonding to zirconia both in conjunction with a primer or MDP cement contained. From the limitations of this study, masticatory forces and anatomical fixed partial denture designs should be valuated to mimic the oral condition rather than the simplified design implanted in the current work. Additionally, further in-vivo studies are required to evaluate the efficacy of the proposed bonding protocols.Within the limitations of the current study and based on the findings, the following can be concluded:1. Alumina-sandblasting and glass-bead pre-treatments improve bond strength of zirconia using MDP-primers or with MDP containing self-adhesive resin cement solely without prior priming.2. MDP containing self-adhesive resin with no prior priming can be used as a successful cementation protocol with less clinical steps for successful zirconia cementation.3. Sandblasting should be combined with a proper chemical treatment strategy to enhance bond strength to zirconia.Supplementary Information.


In this study, a comprehensive approach for sensing object stiffness through the pincer grasping of soft pneumatic grippers (SPGs) is presented. This study was inspired by the haptic sensing of human hands that allows us to perceive object properties through grasping. Many researchers have tried to imitate this capability in robotic grippers. The association between gripper performance and object reaction must be determined for this purpose. However, soft pneumatic actuators (SPA), the main components of SPGs, are extremely compliant. SPA compliance makes the determination of the association challenging. Methodologically, the connection between the behaviors of grasped objects and those of SPAs was clarified. A new concept of SPA modeling was then introduced. A method for stiffness sensing through SPG pincer grasping was developed based on this connection, and demonstrated on four samples. This method was validated through compression testing on the same samples. The results indicate that the proposed method yielded similar stiffness trends with slight deviations in compression testing. A main limitation in this study was the occlusion effect, which leads to dramatic deviations when grasped objects greatly deform. This is the first study to enable stiffness sensing and SPG grasping to be carried out in the same attempt. This study makes a major contribution to research on soft robotics by progressing the role of sensing for SPG grasping and object classification by offering an efficient method for acquiring another effective class of classification input. Ultimately, the proposed framework shows promise for future applications in inspecting and classifying visually indistinguishable objects. One of the most important components of robotic systems is the gripper, performing as system hand to conduct grasping ,2,3,4. WThe human hand is always an extraordinary inspiration for impactive grippers in various aspects ,11,12,13Evidence shows that many researchers have studied the sensing of object properties through impactive grasping. However, available techniques for this function are for conventional impactive grippers with rigid links, broadly known as mechanical grippers. A variety of sensors were integrated into mechanical grippers to determine their internal states, external inputs, and loads ,25,26,27During the recent decades, a new gripper type, widely called a soft gripper, has increasingly obtained considerable interest ,35,36. SOnly a few relevant works were found. Homberg et al.  examinedA comprehensive framework for stiffness sensing through SPG pincer grasping is presented in this study. The presented framework includes the association of the deformation and force on the grasped object and their equivalents on SPAs, a new concept of SPA modeling, and a method for sensing object stiffness through SPG pincer grasping. The importance and originality of this study are that it explicates the combination of stiffness sensing and SPG grasping in a single action. The findings make an important contribution to the field of soft robotics, specifically extending the role of sensing for SPG grasping and object classification for complementing a new domain of classification data with an efficient framework of data acquisition. Future applications of the proposed framework could involve object inspection and classification for objects that cannot be discriminated based solely on their visual appearance.When an object is subjected to external force in the direction normal to its surface, it deforms in the same direction according to the force . Stiffne tensile  and comp tensile  testing.Impactive grasping can be basically categorized, based on morphology, into two main types, including pincer  and enveThis work focuses only on SPG pincer grasping . In SPG ed by FS , as folled by δS , is equited by G , as follThe infinite-DOF structures of SPAs not only complicate the connection of urvature ,59. NoneAccording to published works on SPA modeling, solving Equation (5) is demanding. There is no straightforward analytical method for it, and available simulation solvers are not suitable because of the large deformation and nonlinear characteristics of SPAs. An empirical investigation on an SPA was consequently conducted to obtain its performance curves, serving as an SPA model for comprehensive demonstration. Note that the SPA is an industrial bending type, and its operating rization  was thenThe proposed method of sensing  sensing ,61. Currx-axis intersection point at (Stiffness sensing through SPG pincer grasping on four testing samples, subsequently called thin, slim, medium, and thick sample, was carried out. The testing samples were elastic elastomer hollow tubes , 3D-prinocessing ,63 and socessing ,65. FromIn particular, the workflow of image processing and stereo computer vision began with the image undistortion  on a paiTo validate the proposed method of stiffness sensing, a compression-testing experiment was conducted on the testing samples. Each sample was compressed individually using a load cell driven with a motorized linear stage . SpecifiThe empirically-investigated model of an SPA was first obtained. It contains 10 performance curves , describA length  when FS The experiment of stiffness sensing through SPG pincer grasping was completed. Eleven stereo photographs of SPG pincer grasping , capturepolation . ThroughO curves  were plo plotted , and theCompression testing on the testing samples was successful, and four ollected . The val plotted . The rescomputed . The comIn the cases of the thin and slim samples, n effect , which oThe sensing of stiffness through the pincer grasping of SPGs is presented in this study. The main objective of this study was to clarify the sensing of object stiffness via SPG grasping. The challenge of the study was that the deformation and force on the grasped objects must be associated with their equivalents on SPAs, but SPA structure basically has infinite DOF with nonlinear characteristics. According to SPA compliance, the modeling and sensor installation on SPAs are also sophisticated and novel. We first clarified how object stiffness is conventionally measured, and then presented the connection between stiffness measurement and SPG grasping. The analysis on SPG grasping was completed. Next, the association of the deformation and force on grasped objects to those on SPAs during SPG pincer grasping was formulated. Because SPA curvature is practically inconsistent along SPA length in SPG pincer grasping, available methods of SPA modeling are unfunctional in this case. A new concept of SPA modeling was consequently introduced. Afterwards, a method for stiffness sensing through SPG pincer grasping was proposed and demonstrated on four testing samples. An experiment of compression testing was later implemented to validate the results of the proposed method. The results show that the stiffness of all of the samples perceived with this proposed method slightly deviated from that obtained from compression testing; however, it was still functional for classifying the samples. The contribution and novelty of this study are combining stiffness sensing and SPG grasping into a single action. This study contributes to the fields of soft robotics by leading to the role extension of SPG grasping for sensing applications and object classification by offering an efficient framework for acquiring a new class of classification inputs. The proposed framework has potential for future applications in object inspection and classification, especially for visually indistinguishable objects. A limitation of this study is that the resulting deviation dramatically increased when the deformation of a sample yielded a large value. This phenomenon could be explained by the occlusion effect during the process of visual inspection for SPA deformation. Further studies regarding the direct sensing of SPA deformation should be carried out to overcome the occlusion effect and substantially improve the resulting accuracy of the proposed method. The accuracy improvement is expected to make the outputs of the proposed method viable for higher level tasks, such as identifying grasped objects.


Latarjet procedure is often preferred in recurrent shoulder dislocations accompanied by glenoid bone loss. It is observed that the superiority of bone graft fixation methods is still controversial. The aim of this study is to biomechanically compare the bone graft fixation methods in the Latarjet procedure. 15 third-generation scapula bone models were divided into 3 groups. Graft was fixated in the first group with fully-threaded cortical screws of 3.5mm diameter, in the second group two 16 mm partially-threaded cannulated screws of 4.5mm diameter, and in the third group via a mini plate and screw. The hemispherical humeral head was placed on the tip of the cyclic charge device, and thus, the charge applied to the coracoid graft was homogeneous. No statistically significant difference was found between paired comparisons (p>0.05). The forces in 5 mm displacement in total vary between 502-857N. Total stiffness measurements ranged between 105 and 625; the mean value was 258.13±53.54 with no statistically significant difference by groups (p = 0.958). This biomechanical study showed that there is no difference between three coracoid fixation options in terms of fixation strength. Unlike previous assumptions, plate fixation is not biomechanically superior to screw fixation. Surgeons should consider their personal preferences and experience in choosing fixation methods. However; in the setting of recurrent anterior shoulder instability, caution should be paid to osseous structure of the glenoid as it is an important factor for clinical outcomes. Isolated capsulolabral repair in management of recurrent shoulder instability with significant glenoid bone loss is associated with high recurrence rates. Presence of bony defects on glenoid and humeral head or insufficiency of soft tissue which is required to perform a capsulolabral repair are main indications for coracoid bone block transfer procedures which have become the gold standard for treatment of recurrent anterior shoulder instability with various techniques described.Capsulolabral repair procedures, so called Bankart repair, and coracoid bone block transfer procedures are two options for surgical management of anterior shoulder instability that are currently used in clinical practice. This procedure consists of transfer of coracoid process, like Bristow procedure, along with conjoined tendon through a split of subscapularis muscle to anteroinferior portion of the glenoid and has been demonstrated to be very successful in treatment of shoulder instability in young athletes with bony defects or in patients with hyperlaxity.Latarjet procedure has been used with an increasing frequency and has become the gold standard treatment for treatment of recurrent shoulder instability with glenoid bone defect since its first description in 1954. Despite multiple modifications; rationale of this procedure mostly remains the same. Fixation of the coracoid process most commonly performed using two parallel screws with good long-term outcomes and high fusion rates. Different implants for fixation have also been proposed such as interference screws or plates. Many previous studies comparing different fixation methods have been conducted as the importance of the initial stability and strength of coracoid fixation was understood. Fixation of coracoid graft using mini-plate has been favored by some authors with consideration of stronger initial fixation, better stability, uniform load distribution between graft and glenoid and therefore faster union. However; to our knowledge, there are no biomechanical study comparing fixation strength of mini-plate to other fixation implants in current literature.Stable and strong initial fixation of transferred bone block is a prerequisite for success of this procedure in order to minimize the risk of non-union and to initiate a reliable rehabilitation with early mobilization. Non-union was reported to be one of the most common causes of recurrence and it has been shown that failure mechanism was triggered by non-union in 42.3% and by graft resorption in 23.1% of the cases.The purpose of this biomechanical study was to compare strength of initial fixation, load-to-failure and mode of failure of Latarjet procedure performed by two cortical screws, two partially-threaded cannulated screws and mini-plate. We hypothesized that there would be no significant biomechanical difference among three fixation methods. Afterwards, each bone model underwent coracoid transfer procedure according to the technique described by Latarjet. Coracoid osteotomy was performed using a 10x0.5 mm cutting saw at coracoid base with graft length 20-25 mm. The concave inferior surface of the coracoid process was rasped and flattened in order to obtain a better fixation into the defective region of glenoid.This study was approved by the institutional review board and was performed in accordance with the principles of the Declaration of Helsinki. The ethics committee protocol approval number is 2017-475636. Fifteen third-generation scapula bone models (Selbone®) were obtained. A bony defect which covers 25% of the articular surface of glenoid on anteroinferior portion was created by cutting saws using a template adapted to glenoid surface of each bone model similarly as described by Itoi et al.Fifteen samples were allocated into 3 groups. Group 1 consisted of fixation using two 3.5mm fully threaded cortical screws . In second group, fixations were performed using two 16 mm partially threaded cannulated screws with 4.5mm diameter  and in third group, mini plate and screws  were used for fixation.In group 1, following the creation of glenoid defect and coracoid osteotomy, two holes were drilled through coracoid graft using a 3.5mm cannulated drill bit over two parallel Kirschner wires. Then, the coracoid graft was positioned onto defective glenoid area flush with or slightly embedded (<1mm) to articular surface and two glenoid holes were drilled through two holes which were drilled on coracoid graft using a 2.5mm drill bit while holding the graft in correct position. Fixation was then performed using two 3.5 mm fully threaded cortical screws at appropriate length following length measurements and specimens were prepared for tests.   In group 2, coracoid graft was positioned in a similar way to group 1 and temporarily fixed to glenoid using two parallel Kirschner wires. Then both coracoid graft and glenoid holes were drilled using a 3.2mm cannulated drill bit over these K-wires. Following length measurements, fixation was performed using two 16 mm partially threaded cannulated screws of 4.5mm diameter. After ensuring that the threads of cannulated screws are attached to the glenoid neck, which is the most distal cortex, in order to avoid rotational displacement, K-wires were removed and specimens were prepared for tests.   In group 3, osteotomized coracoid graft was positioned to the defective area similarly to group 1 and group 2 and temporarily fixed using two parallel K-wires paying attention to plate hole positions. Then, both graft and glenoid holes were drilled using a 3.2mm cannulated drill bit. Following length measurements, plate was inserted over K-wires and fixation was performed using two 4.5 mm partially-threaded cannulated screws. Attention was paid that notches of the plate were in contact with graft cortex and compressed the coracoid.   Each specimen was inserted into a round-shaped, polyvinyl chloride container filled with polyester paste and benzoyl peroxide, which is a hardener and accelerator, and held in adequate position until the specimen is solidified.    The hemispherical stainless-steel part that would simulate the humeral head was placed on the tip of cyclic charge device thus, homogeneous load distribution to graft was aimed. The prepared samples were inserted to test device so that a vertical load to coracoid graft would be applied in order to simulate the worst-case scenario. . The test protocol has been prepared according to previous biomechanical studies.enario.    failure was determined as 5mm displacement of the graft relative to its initial position. The primary outcome was determined as load required in Newton (N) for 5mm of graft displacement (load-to-failure). Load-to-failure results and mode of failure were documented for data analysis.In order to precondition the construct, 100 cycles of load were performed between 0 and 20N and a break of 30 minutes was carried out following preconditioning. Then the constructs were tested to failure with static load applied to all specimens with loading speed set to 1 mm/minute until macroscopic failure occurs. A load-displacement graph    was obtAll analyses were performed using GraphPad Prism Software for Windows . Mean, standard deviation, median, range, minimum and maximum were used as descriptive statistical methods in order to analyse the data. Distribution of variables was tested using Shapiro-Wilk test and Kolmogorov-Smirnov test. Comparisons between three study groups were performed using analysis of variance (ANOVA). Post-hoc pairwise comparisons between groups were performed using Tukey’s. The significance level was at p=0.05 for all analyses. A post-hoc power analysis was performed on to primary outcome (load-to-failure) using .The mode of failure in group 1 was complete screw pull-out without screw deformation in four cases (80%) and glenoid fracture in one case (20%). In group 2, mode of failure was screw pull-out in three cases (60%) and glenoid fracture in two cases (40%). The mode of failure with plate fixation was screw pull-out in two cases (40%) and glenoid fracture in three cases (60%)   . None oOverall load-to-failure ranged between 502-857 N with a mean of 700±109N. Mean load-to-failure was 707.8±116.9 N (range: 545-800N), 687.8±99.3N (range: 587-810N) and 705.2±132.1N (range: 502-857N) respectively in three study groups. No statistically significant difference was observed between three groups (p=0.958).   ,  Tabl Two-tailed post-hoc power analysis revealed that the power of the study was 81.9% for load-to-failure with 15 samples and α=٠.٠٥.The main finding of the present study was that accordingly to our hypothesis, initial strength and stability of the coracoid fixation did not differ biomechanically between cortical screws, cannulated screws and mini-plate. These findings implicate that surgeons may choose the fixation methods based on their experience and preference without significantly altering the construct biomechanically. However; complication rate following bone block transfer procedures has been reported to be between 15 and 30%. Reported complications include infection, nerve injuries, glenoid fracture, graft non-union or osteolysis and recurrent instability. Accurate positioning and proper fixation of the coracoid graft have been reported to be essential for clinical success of this procedure in order to withstand the axial and shear forces of the glenoid joint and to avoid fixation failure which can lead to graft non-union and recurrent instability. Therefore, choosing the optimal fixation method plays an important role for success of this procedure.The Latarjet procedure is being more frequently used in recent years and successful results have been reported in management of recurrent shoulder instability. Another cadaveric study by Weppe et al. compared the initial fixation strength of two metal bicortical screws and a bioabsorbable interference screw and showed that metal screws provided stronger fixation. A recent biomechanical study by Alvi et al. biomechanically compared solid and cannulated screws and consistently found no significant difference in terms of load or cycles to failure.Screw fixation is the most commonly used technique for fixation of coracoid graft and studied by many previous biomechanical or clinical studies. In their cadaveric study, Shin et al. did not find significant biomechanical difference between different screw types  and fixation methods . Therefore, fixation with two unicortical screws has been proposed in order to avoid possible nerve injury. However; in contrast to previous study by Shin et al. Schmiddem et al. recently showed that monocortical fixation was significantly weaker compared to bicortical fixation. In our study, we performed bicortical fixation, which is a prerequisite in order to obtain sufficient initial fixation strength to our opinion and consistently to previous data, we found no biomechanical difference between cortical and cannulated screws.Anatomical proximity of the suprascapular nerve to exit sites of the screws in bicortical fixation method poses the possibility of an iatrogenic injury of the suprascapular nerve due to drilling or to the prominence of the screws. configuration of the plate provides a better torsional orientation and four spikes of the plate improves the stability in plate-graft interface. Consequently, these properties are believed to allow even distribution of the load to the bone compared to conventional screw fixation methods. A retrospective case series by Chaudhary et al. reported outcomes of 24 patients with failed arthroscopic Bankart repair and who were treated with Latarjet procedure using mini-plate fixation. Authors reported good clinical outcomes and no recurrence of instability. Another study by Di Giacomo et al. clinically and radiologically compared their results with mini-plate fixation to the results of their previous study without using mini-plate. They divided the coracoid bone graft into eight parts and evaluated for osteolysis using post-operative computed tomography scans. Their results showed that only deep part of the distal coracoid was significantly less involved in osteolysis with mini-plate fixation without any clinical difference. Authors concluded that mini-plate fixation did not provide reduced risk for graft osteolysis but they recommended its use to improve graft stability. However; there is a paucity of data concerning biomechanical properties of mini-plate fixation in Latarjet procedure and to our knowledge, our study is the first biomechanical study comparing mini-plate fixation to different screw fixation methods. The findings of our study revealed that mini-plate fixation was biomechanically comparable to fixation with two cortical or cannulated screws.The Latarjet mini-plate has been developed in order to obtain better biomechanical properties and is thought to enhance compression of the graft to glenoid bone surface. The plate has a wedge profile and allows medial rotation of the coracoid graft with applied compression and therefore improves the contact between coracoid graft and glenoid bone surface. The figure of eightThere are several limitations to the present study which are inherent to a biomechanical bone model study. Inability of the biomechnical test setup to reflect in vivo mechanics may be listed as a limitation of our study. Eventhough our test setup aimed to assess strength of graft fixation rather than glenohumeral joint stability, effects of soft tissue structures such as sling effect of conjoined tendon, capsular repair and subscapularis muscle could not be represented in a biomechanical test setup with bone models. Another limitation is that all native forces effecting coracoid graft, such as counter pull force produced by biceps muscle which is a contributing factor for fixation failure especially in early post-operative period, could not be reproduced in our test model. The load was applied in a single direction, perpendicular to coracoid graft which may not accurately represent in vivo graft loading after Latarjet procedure. Also due to our test mechanism we have been tested only load-to-failure loading. Absence of cyclical loading, which is known as another failure mechanism of Latarjet procedure, is another limitation of our study. However, we simulated the worst-case scenario which allowed better standardization of the load magnitude acting on the graft. Finally, the study was conducted as time-zero analysis therefore post-union biomechanics could not be evaluated.There are also some strengths of the study. Due to homogeneity of the used bone models, possible standardization problems related to cadavers  have been avoided. A uniform surgical technique was performed and biomechanical testing was designed and standardized to simulate the worst-case scenario.Strength of initial fixation is essential for the success of Latarjet procedure and the findings of this biomechanical study showed that no difference exists between three coracoid fixation options  in terms of fixation strength. Unlike previous assumptions, plate fixation is not biomechanically superior to screw fixation. Surgeons should consider their personal preference and experience choosing fixation methods but further research with high evidence are needed.


The global spice trade has played an essential role in world history. However, because of poor preservation conditions, archaeobotanical remains of spices have been limited in archaeological contexts until now. This study reports evidence for spice processing from the archaeological site of Oc Eo in southern Vietnam, an entrepôt of the state of Funan that was occupied during the early centuries CE. Analysis of plant microremains recovered from the surfaces of Oc Eo grinding stone tools thought to be of South Asian origin has identified culinary spices that include turmeric, ginger, fingerroot, sand ginger, galangal, clove, nutmeg, and cinnamon. These spices are indispensable ingredients used in the making of curry in South Asia today. We suggest that South Asian migrants or visitors introduced this culinary tradition into Southeast Asia during the period of early trade contact via the Indian Ocean, commencing about 2000 years ago. Understanding of the ancient spice trade is expanded through analysis of 2000-year-old processing tools from Vietnam. Curcuma), cinnamon (Cinnamomum), and black pepper (Piper nigrum) from South Asia to the Mediterranean during the second millennium BCE (Before the Common era) , clove (Syzygium aromaticum), nutmeg (Myristica fragrans), and cardamom (Elettaria cardamomum) (Piper longum) . The whole site complex covers an area of some 2,500 ha, including the lower slopes and summit of Mount Ba The and an adjacent floodplain to its southeast that has several natural but low-lying mounds  came from a charcoal sample collected from slightly below our largest grinding slab (sample code OE18.LLO.B.H1.M1.L3.3)  (SupplemOryza sativa)  having five subtypes (Ia to Ie). Thus, we recognized a total of eight different spices, together with a presence of rice ( sativa)  (Supplemn = 604), 514 granules could be identified as coming from eight different identified spices. Of these, 316 belonged to Zingiberaceae species  account for the largest proportion of these and are elongated and ovate in shape with an eccentric protruding hilum  (Boesenbergia rotunda)  are quite unique, with a sub-rounded shape and a highly eccentric and convex hilum  (Among the five main types  of identified starch  . Thirty-rotunda) . The staex hilum . Forty ngalanga) .In addition to Zingiberaceae, starch grains from three other plant families were found on the Oc Eo processing tools. They include clove seeds (Type II) that have ovate starch grains with an eccentric hilum and visible lamellae . SeveralCinnamomum sp.). Thirty-seven starch grains of Type IV can be identified as nutmeg (M. fragrans); these are characterized by round shapes and radiating or linear fissures  were also found in our samples, together with the spheroid echinate phytoliths from palms (Cocos nucifera), according to comparisons with modern reference samples (Musa (Starch grains (Type V)  and phytom palms . Notablyom palms . They we samples . Eleven es , fingerroot (B. rotunda), and sand ginger —are all native to tropical Asia and widely cultivated today in Southeast Asia. Their precise origins are uncertain  have been recovered from Kantharodai (ca. 200 BCE) and Kirinda (ca. 260 to 900 CE) in Sri Lanka (Alpinia officinarum) is reported from the Mawangdui Western Han Tomb (second century BCE) in Hunan province, China (B. rotunda) and sand ginger —are used today as seasonings and herbal medicines and also have a long history of utilization in Southeast Asia  completed ca. 200 CE, the Han Dynasty court had a rule that ministers should suck cloves to sweeten their breath before speaking to the emperor , often termed the “Spice Islands” . The comBefore this study, the earliest potential evidence for cloves, dated to ca. 1700 BCE, came from the Middle Bronze Age site of Terqa in Syria, but the identification remains controversial , and this is so far the oldest nutmeg specimen in Mainland Southeast Asia.Cinnamomum (Cinnamomum verum) and is native to Sri Lanka (Cinnamomum cassia), Saigon cinnamon (Cinnamomum loureiroi), Indonesian cassia (Cinnamomum burmannii), and Indian cassia   at specific densities of 1.9 and 2.35 were added to isolate the starch grains, phytoliths, and other microfossils. Among the 40 stone implements, 12 produced good samples of starch remains, while the rest produced less than five starch grains each.The starch grain samples were then each mounted on a glass slide in a solution of 10% glycerine and 90% water and scanned under an Olympus microscope at magnifications of ×200 and ×400 with both white and cross-polarized light. The phytolith samples were mounted on slides with Canada Balsam and scanned at ×400 magnification. The starch grains, phytoliths, and other microbotanical remains such as pollen grains, vessels, and fibers were counted, photographed, and measured with regard to their morphological characteristics.The ancient starch identifications are based on comparisons with the starch grains of more than 200 Asian species (Phytoliths were identified following previously published references and criteria (


Introduction: Synthetic vascular grafts have been widely used in clinical practice for aortic replacement surgery. Despite their high rates of surgical success, they remain significantly less compliant than the native aorta, resulting in a phenomenon called compliance mismatch. This incompatibility of elastic properties may cause serious post-operative complications, including hypertension and myocardial hypertrophy.Methods: To mitigate the risk for these complications, we designed a multi-layer compliance-matching stent-graft, that we optimized computationally using finite element analysis, and subsequently evaluated in vitro.Results: We found that our compliance-matching grafts attained the distensibility of healthy human aortas, including those of young adults, thereby significantly exceeding the distensibility of gold-standard grafts. The compliant grafts maintained their properties in a wide range of conditions that are expected after the implantation. Furthermore, the computational model predicted the graft radius with enough accuracy to allow computational optimization to be performed effectively.Conclusion: Compliance-matching grafts may offer a valuable improvement over existing prostheses and they could potentially mitigate the risk for post-operative complications attributed to excessive graft stiffness. Synthetic vascular grafts are widely used in clinical practice for vascular and cardiac surgery for over 50 years . One of Although there have been major improvements in synthetic grafts for large arteries to facilitate the application and reduce the operation time, little has been done to address their inability to mimic the elastomechanical properties of the native aorta. Elasticity is a major concern with regards to the aorta, because it is its compliance that allows the aorta to act as a buffer to accommodate the pressure oscillations during the cardiac cycle and to propel the blood to the periphery. This function is known as the “Windkessel effect.” When synthetic grafts, that are multiple times stiffer that the native tissue, replace the aorta, the aortic compliance is decreased substantially . This, iThe difference in elastomechanical properties between the healthy aortic tissue and the aortic grafts is often termed as “compliance mismatch.” The absence of compliant aortic grafts has dissatisfied clinicians and it has led scientists to question the ability of existing grafts to mimic the physiological function of the aorta . Researcin vitro via simultaneous acquisition of pressure, volume, and radial displacement. Thereby, we validated the FEM simulation and verified that the prosthesis manifests the specified compliance in typical implantation conditions.Here, we aimed to design a biomimetic and biocompatible vascular graft that is matching the compliance of healthy human aortas. We optimized the graft’s properties computationally based on finite element method (FEM) simulations. Consequently, we fabricated the graft and measured its properties To design the compliance-matching (CM) graft, we drew inspiration from the natural structure of large elastic arteries. Their medial layer consists of a network of interconnected elastin fibers, stiffer collagen fibers, and smooth muscle cells. In the unloaded state, both the elastin and collagen fibers are undulated and wavy. However, at physiological pressure, the elastin fibers are mostly disentangled, while the collagen fibers are only partially engaged . This alImportantly, the compliance or equivalently, the deformability of a construction does not depend solely on its material, but also on its shape and structure. It may seem counterintuitive that the metallic stents are more compliant that the woven graft, but it is a feature that could be achieved by appropriate design. A thin metallic tube, for example, could be more compliant that a thicker plastic one, even if the elastic modulus of the metal is much higher than that of the plastic. This can be easily proven by using the Moens-Korteweg equation:  Einch . In our f) and the martensite deformation temperature (Md), resulting in superelastic elastic behavior. The stent diameter was smaller than the diameter of the PET graft (inner layer), to achieve the necessary compression. The stents were inserted over the inner layer with a custom mandrel and were secured using 2-0 non-absorbable silk sutures with two suture points per stent. We fabricated grafts of three diameters to verify that the design approach could work for grafts of varying sizes.The inner layer consisted of a pleated, woven, commercial graft , which was made of polyethylene terephthalate (PET) and was impregnated with gelatin. The inner layer was one of the current gold-standard aortic grafts, which are recognized for their mechanical strength, ease of manipulation and their long-term size retention . The nomWe created a detailed FEM simulation of the composite graft, aiming to predict its behavior and specifically, its area compliance. We designed a generalized stent model completely parametrically, so that we can control the design with a small set of parameters, including the stent diameter, strut length, stent spacing, circumferential step, strut width, radius of curvature, and strut thickness . Then, wWe imposed the same FEM modelling parameters to all the designs. The PET graft was modelled as an isotropic, hyperelastic, third-order Ogden material  with neaInitially, we performed a sensitivity analysis to determine the subgroup of stent design parameters that had a major effect on the compliance of the graft. These parameters consisted of the stent dimensions and the thermal properties of the material. We excluded parameters that we would not be able to control during the manufacturing. We selected the six parameters with the largest main effects on compliance and we created a 6-factor Box-Behnken design  to calcuTo estimate the material properties of the graft and stent, we performed uniaxial tensile strength measurements on an ElectroPuls E3000 fatigue testing machine  with standard methodology . We impoThe compliance of the assembled grafts was then measured in a hydraulic circuit, that was specifically built for this application . The cirThe testing protocol consisted of ten preconditioning and ten experimental stress-controlled cycles of inflating the prosthesis in the 50–200 mmHg pressure range with a loading frequency of 0.2–0.5 Hz. The magnitude of the volume flow rate was kept constant throughout each experiment, resulting in non-linear loading due to the nature of the experiment, which consisted in inflating a cylindrical sample. The applied testing and measurement procedure was similar to the standard testing procedure for vascular prostheses . Using tWe recorded the signal from all sensors simultaneously on a PowerLab  data acquisition device at 1 kHz. All measured signals were filtered using a low-pass filter with cut-off frequency of 50 Hz to remove the utility frequency and higher frequency noise. The sampling and cut-off frequencies were sufficiently higher than the inflation frequency. First, we used the measured pressure and the imposed volume flow rate of the programmable pump to create the pressure-volume curve. Since woven grafts have minimal axial rigidity, they bend and deviate from the centerline as the transmural pressure increases. We accounted for the pressure-induced bending by assuming that the graft will adopt the shape of a beam fixed at both ends under a bending load. Therefore, we derived analytically a function that provides the length of the bent graft based on the measured maximum radial deflection. With this function, we adjusted the volume of the graft so that it corresponded only to the radial inflation, without the change of volume caused by the elongation due to bending.Based on the experimental measurements, we calculated the volume compliance as t-test or with Welch’s t-test as appropriate. Multiple comparisons were corrected with the Holm-Bonferroni procedure. Correlations were evaluated using linear regression analysis and the Pearson’s correlation coefficient (r). The level of statistical significance for all analyses was set to 0.05. Values are reported as mean (SD).We programmed the optimization algorithm, the experimental data processing code and the statistical analysis in Matlab . Means were compared with paired samples The relationship between pressure and diameter of both CM and PET grafts was measured experimentally in the hydraulic circuit . The rad2/mmHg and 0.025 mm2/mmHg for the same pressure ranges, respectively. Additionally, we assessed the accuracy of the FEM simulation with linear regression analysis  of 0.022 mm over the physiological aortic pressure range (80–120 mmHg) and with a RMSE of 0.018 mm over the extended pressure range (50–200 mmHg). The RMSE in the estimation of area compliance was 0.018 mmanalysis . The slo rapidly , and the−3 mmHg−1 (SD 0.17 × 10−3) at a reference pressure of 100 mmHg under the expected implantation conditions . The CM graft distensibility was within the reference range of aortic distensibility of healthy, normotensive adults (p < .001) the distensibility of both compliant and PET grafts (p < .001) when we introduced a 10% longitudinal prestretch, while the same prestretch caused a 56% reduction (p < .001) in the distensibility of PET grafts. At all tested levels of prestretch, the distensibility of CM grafts was higher than that of PET grafts (p < .001). An increase in temperature resulted in a significant increase  in the maximum distensibility of both graft types in the 80–140 mmHg pressure range (p < .001).A radial compression of 10%–15% was enough to increase the compliance without introducing excessive folding in the inner layer. The optimized CM grafts reached a distensibility of 1.60 × 10e adults  up untile adults . Taking e adults . PET graT grafts . The disre range . HoweverThe results of our study suggest that our novel graft can reach the compliance of healthy human aortas, even that of young adults. Our CM graft could reach physiological levels of compliance for most of the aortic pressure range expected in adults. This accomplishment separates our CM graft from gold-standard aortic grafts, whose compliance is multiple times lower than the physiological range. The experiments presented here show that it is possible to increase and regulate the compliance of a graft by compressing it with optimally designed stents. To the best of our knowledge, the proposed prosthesis is the first that could solve the issue of compliance mismatch, utilizing a biocompatible design that could retain its properties after implantation, without sacrificing the remaining characteristics of existing gold-standard grafts. The CM graft compliance is within the reference values for aortic stiffness based on pulse wave velocity measurements , and wit−5 mmHg−1, which is two orders of magnitude lower than the CM graft and the physiological range. These findings are contrary to the role of the stents in the CM graft, which is primarily to increase the compliance, although they could be used additionally for endovascular delivery. The endovascular delivery of the CM graft could be easily achieved by compressing the CM graft with a retractable sheath. Given that the nitinol stents are designed to be in their superelastic region at body temperature, the CM graft would behave as a self-expanding stent-graft, after the removal of the retractable sheath.The concept of stent-grafts has already been introduced for endovascular aortic reconstruction. Contrary to the proposed solution, the stents are utilized in the existing prostheses only for applicability purposes to allow for endovascular repairs. In fact, the stents reduced the compliance of the prosthesis and increased the pulse wave velocity, a clinical measure of aortic stiffness, at the abdominal aorta . ExistinWe showed that it is possible to increase the compliance up to approximately six times by introducing radial compression. The compression was small enough to allow the prosthesis to function properly but without altering the implantation procedure compared to a standard graft. Due to the minimal rigidity of thin fiber-based tubes in the compressed state, the compression method is expected to work not only with PET but also with other types of synthetic and even biological grafts. The stent parameters would have to be re-optimized based on the specific material combination. The concept of compression has been investigated previously, utilizing springs and compression plates , a solutThe effect of the unfolding and gradual engagement of the compressed fibers of the inner layer can be clearly seen in the pressure-dependent behavior of the graft , 7. As e−3 mmHg−1) to our graft, but it quickly diminished to non-physiological levels with increasing pressure. The stented version of the same graft had even lower distensibility (0.5 × 10−3 mmHg−1). It is also expected that as the knitted fibers of that or of similar grafts extend in the axial direction, they could quickly lose their ability to extend circumferentially, thereby reducing their compliance further.As shown, it is important for the prostheses to have the desired properties at the expected implantation conditions. That is because conditions, such as longitudinal prestretch and temperature, greatly affect the properties of the prostheses . Longituin vitro, while the effects were more prominent in larger grafts (Another aspect of implantation conditions, that is often overlooked, is how the organism’s reaction to the prosthesis will affect its long-term properties. Woven dacron grafts, similar to the inner layer of the CM graft, were found to maintain their diameter after the implantation, showing only a 5.5% diameter increase after a mean period of 13 years . This war grafts . The resr grafts . The latr grafts , while tThe FEM simulation and the computational optimization aided and accelerated the development of the compliant grafts. We validated successfully the results of the FEM simulation using experimental data of the whole stent-graft . The FEMIn the literature there is a notable absence of validated models that could estimate the pressure-dependent properties of vascular prostheses. We found FEM simulations that were constructed for fiber-based grafts and they produced very accurate results . SimilarAs for the computational optimization, its use is still limited in the field of vascular prostheses and, especially, stent-grafts, in spite of the many advantages the method has to offer. Researchers have used computational fluid dynamics to find the optimal volume ratio and diameters of abdominal endoprostheses to reduce thrombosis risk . Multi-lin vitro and in silico approach allows. Future experiments in suitable animal models will be necessary to prove that the proposed graft could offer augmented compliance in vivo, and to verify if the augmented compliance translates to improved clinical outcomes and clinical significance. The animal experiments would also be appropriate to assess whether the addition of stents could lead to problems such as graft delamination or rupture, although based on existing stent-grafts, this is a rare complication. Furthermore, to reduce computational time we optimized and evaluated the compliance in quasi-static simulations and experiments, while the matching compliance was assessed by neglecting the effects of anisotropy, viscoelasticity, and prestress of the arterial wall. Additional optimization would be required to design CM grafts that could be compressed to the desired diameter for endovascular repairs, and anchor stents would be mandatory at the proximal and distal ends to secure the graft on the aorta.Our findings are limited to the extent of validation that a combined in vivo experiments to prove the beneficial effects of increased graft compliance on the cardiovascular system. The methodology, that was developed in this study, not only enables the optimization of stent-graft properties, but it also unlocks the potential for personalized vascular prostheses in the future. We believe that the compliant grafts could reduce the post-operative complications that are caused by current prostheses, thereby improving the quality of life and life expectancy of patients submitted to aortic replacement surgery.We conclude that the proposed compliance-matching graft can attain the compliance of healthy, human aortas and it could mitigate the phenomenon of compliance mismatch along with the associated risks. The proposed grafts retain their compliance within physiological levels in a wide range of operating conditions, contrary to existing prostheses that are multiple times stiffer than the aorta. The selected materials are biocompatible, thus enabling the potential for


Many techniques have been described for reconstruction of the acetabular labrum, but the procedure is known to be technically rigorous leading to lengthy procedure times and traction times. Increasing efficiency of the procedure with respect to graft preparation and delivery remain areas for potential improvement. We describe a simplified procedure for arthroscopic segmental labral reconstruction using peroneus longus allograft and a single working portal to shuttle the graft into the joint via suture anchors placed at the terminal extents of the graft defect. This method allows for efficient preparation, placement and fixation of the graft that can be completed in under 15 minutes. This technique demonstrates segmental reconstruction of an acetabular labrum with the use of a single working portal in a right hip. Two standard anterolateral (AL) and modified midanterior (MA) portals are established with the AL used as the viewing portal and the MA the single working portal. A peroneus longus allograft, 5-6 mm in diameter is the preferred graft choice. There are many different approaches, and these techniques typically involve either the creation of a third arthroscopic portal and/or the use of various complex intra-articular suture management techniques to secure the graft. For example, the knotless pull-through technique published by Perets et al. requires the creation of a distal lateral anterior portal (DLAP) in order to introduce the graft into the joint.As arthroscopic labral reconstruction is known to be a technically challenging procedure, the goal of this article is to present a simplified and reproducible technique for acetabular labral reconstruction that minimizes procedural steps, thus reducing operative time and traction time which is important for reducing risk for complications.,Diagnostic arthroscopy is first performed to evaluate the viability of the labral tissue. In this case, a degenerative and diminutive labrum was identified A, and a Once ready to proceed with labral reconstruction, we begin by assessing the size of the defect. Multiple methods are available for arthroscopic measurement; we prefer using the end of an arthroscopic probe A, which The graft is then prepared, which can be performed by an assistant once the size of the labral defect has been determined. We prefer the use of a peroneus longus allograft that is 5-6 mm in diameter, similar in size to an intact and normal labrum. The tubular/triangular distal end of the graft will be used for the reconstruction A. A ruleThis technique for segmental labral reconstruction is performed through an 8x90mm disposable cannula in the MAP without switching working portals and can be efficiently completed in under 15 minutes. This technique can also be utilized for varying defect lengths and a variety of locations around the acetabulum. Longer segmental graft reconstructions can be accomplished, as seen in this example of a reconstruction that used four suture anchors A, 6B. ItAdvantages and disadvantages  as well Arthroscopic labral reconstruction is well-known to be a challenging procedure, as multiple techniques published over the last decade involve either the creation of a third arthroscopic working portal and/or complex suture management techniques to secure the graft. The “Kite Technique” is one method of labral reconstruction that requires both an additional portal and intricate suture management.In contrast to these techniques, we have found that by using the suture-anchor based shuttling method in our current technique, the graft can be reliably delivered into the central compartment through a single working portal. By shuttling the graft via suture anchors placed at the terminal edges of the labral defect, the need for complex suture passing and management is minimized, thus simplifying the delivery of the graft into the joint. After the terminal anchors are tied, additional anchors can then be placed in between and tied one at a time similar to a simple labral repair, eliminating excessive suture passing and opportunities for entanglement. In addition, the single working portal technique presented in this article allows the surgeon to address both anterior and posterior labral defects by utilizing the MA or the AL portal respectively, as the primary working portal.In our review of the literature, we found previously published techniques for labral reconstruction using the standard AL and MA portal. However, the strategies for graft delivery and fixation varied substantially from the method presented here. Park et al. described a two-portal technique using quadriceps tendon autograft.In conclusion, we present a technique for arthroscopic segmental acetabular labral reconstruction using a single working portal and peroneus longus allograft that can be completed in under 15 minutes. This simplified technique improves the efficiency of the procedure by delivering both ends of the graft through a single working portal with anchors placed at the anterior and posterior extents of the labral defect followed by routine labral repair between the terminal anchors after graft docking.


In this study, starch ferulate was synthesized employing a mechanoenzymatic method, specifically based on the twin screw extrusion technique and lipase catalysis. The research then primarily centered on optimizing process parameters and conducting structural analysis. Optimal conditions were determined to be 8.2% ferulic acid addition, 66 °C extrusion temperature, and 3.2% lipase (N435) addition. The enzyme-catalyzed time was 30 s. The degree of substitution for starch ferulate was quantified at 0.005581 under these specific conditions. The presence of C=O bonds in the synthesized starch ferulate proved that the synthesis process was efficient. Additionally, the crystal structure underwent reconstruction. Observations through Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM) demonstrated that the mechanoenzymatic method led to an augmentation in the specific surface area of starch molecules, thereby facilitating the exposure of active sites. This breakthrough underscores the vast potential of mechanoenzymatic techniques to revolutionize the rapid and sustainable synthesis of starch ferulate, marking a pioneering stride in ester synthesis. The insights garnered from this study transcend theory, offering a visionary roadmap for the development and real-world deployment of advanced modified starch esters. Starch-based materials are now often used to meet individualized nutritional needs. Their unique physicochemical characteristics have also been shown to facilitate the precise delivery and release of active substances . Corn stIn recent years, within the food and beverage industries, ferulic acid has frequently been incorporated as a health-promoting factor into various products, thereby enhancing their functional benefits . NeverthThe synthesis of starch ferulate (SF) effectively addresses the challenge of ferulic acid’s limited ability to reach the colon for functional impact. Starch ferulate, as an innovative variant of modified starch (esterified starch), demonstrates a diverse array of functionalities encompassing anti-depressant, hypoglycemic, anti-colorectal cancer, cardiovascular disease treatment, antioxidant, and thrombosis regulation properties . FurtherIn view of the advantage that mechanoenzymatic catalysis possessed in terms of high efficiency and lack of dependence on organic solvents, we have undertaken the utilization of twin screw extrusion (TSE) technology to synthesize starch ferulate. Twin screw extrusion employs mechanical shear forces, high-frequency vibrations, and frictional forces under high-temperature and high-pressure conditions to induce physical and chemical changes in materials ,10. As aCorn starch, as a resistant starch, also has excellent physiological activity and immunomodulatory potential. Therefore, its further modification and application is essential . This stCorn starch (food grade) was sourced from China National Cereals, Oils and Foodstuffs Corporation (COFCO) Biochemical & Energy Co., Ltd. . Ferulic acid (99%) was purchased from Aladdin Biochemical Technology Co., Ltd. . Lipase  was supplied by Bide Pharmaceutical Technology Co., Ltd. . The rest of the reagents  were provided by Sinopharm .w/w), and this starch solution was combined with the iso-octane solution (20 mL) of lipase. Upon the addition of ferulic acid, the mixture was processed using a twin screw extruder  at a speed of 20 Hz [Corn starch was mixed with water , 3% lipase dosage, and an extrusion temperature of 65 °C, the evaluation was carried out to assess the influence of different levels of ferulic acid  on the degree of substitution.Under the conditions of a screw rotation speed of 20 Hz, a water addition rate of 20% (w/w), ferulic acid dosage of 8%, and lipase dosage of 3%, the evaluation was performed to analyze the impact of different extrusion temperatures  on the degree of substitution.Under the conditions of a screw rotation speed of 20 Hz, a water addition rate of 20% (w/w), ferulic acid dosage of 8%, and an extrusion temperature of 65 °C, the assessment was conducted to analyze the influence of different levels of lipase dosage  on the degree of substitution.Under the conditions of a screw rotation speed of 20 Hz, a water addition rate of 20% (Using ferulic acid dosage (A), extrusion temperature (B), and lipase dosage (C) as individual factors, and degree of substitution (Y) as the response value, a three-factor three-level response surface experiment was designed. It should be noted that since the degree of substitution was a measure of the degree of modification, it was used as a criterion for response surface optimization. The Design-Expert software (v 8.0.6) and the principles of Box–Behnken design were employed to determine the optimal modification process parameters for preparing starch ferulate using twin screw extrusion.The degree of substitution of starch ferulate was determined by a TU-1950 UV-Vis spectrophotometer . Following the extraction of the hydrolyzed starch ferulate solution using ethyl acetate, the absorbance value of alkali-dissolved ferulic acid was determined. Subsequently, the degree of substitution was calculated using a linear regression equation to ascertain the concentration of ferulic acid .2 = 0.9993.Standard solutions of ferulic acid were prepared with mass concentrations of 0, 1, 2, 3, 4, 5, and 6 μg/mL. The absorbance values of these solutions were subsequently measured at 320 nm. Using the absorbance values as the vertical coordinates and the mass concentrations of ferulic acid solutions as the horizontal coordinates, standard curves were plotted A. The liA mass of 0.10 g of starch ferulate was placed within a conical flask and combined with a 1 mol/L NaOH solution. Stirring was conducted magnetically at 50 °C for a duration of 3 h to induce hydrolysis. Subsequently, the pH was adjusted to 2 with a 1 mol/L HCl solution while maintaining the elevated temperature. After a defined time interval, the hydrolyzed solution was subjected to extraction using ethyl acetate, a procedure that was repeated four times. The resulting extracted solution was set aside for subsequent utilization.W (%) is the mass fraction of ferulic acid in starch ferulate; C (mg/L) is the mass concentration of ferulic acid calculated from the standard curve; V (mL) is the volume of the extraction solution; m0 (g) is the mass of starch ferulate; M (194.19) is the relative molecular mass of ferulic acid; 162 (g/mol) is the molar mass of one glucose unit; and DS is the amylose substitution degree.The absorbance value of the extract was measured at 320 nm and the ferulic acid content in the starch ferulate was calculated from the standard curve. The degree of substitution was calculated according to the following equations .(1)W=C×Before calculating the degree of substitution, it is essential to perform a washing step on the reaction product obtained after twin screw extrusion. This washing process involves centrifugation with anhydrous ethanol, followed by the analysis of the supernatant using thin-layer chromatography (TLC). Specifically, an appropriate amount of unfolding agent (hexane: ether: benzene: dichloromethane = 1: 10: 15: 25) was pipetted into the unfolding cylinder. The centrifugation supernatant was then dipped into a spotting capillary and spotted on a silica gel thin-layer plate. And ferulic acid standard was utilized as a control at the same horizontal position. Once the silica gel thin-layer plate had been impregnated and penetrated by the elution solvent to a distance of 3 cm from the upper edge, it was carefully extracted and subjected to air-drying. Subsequently, the silicone thin-layer plate was exposed to ultraviolet lamp irradiation. If only a singular discernible fluorescent sample spot manifested, it signified successful purification, and the plate was deemed clean and ready for the final drying process, preparing it for subsequent applications.The samples were scanned by UV full wavelength (200–800 nm) spectroscopy  while anhydrous ethanol was used as a control .−1, resolution: 4 cm−1, number of scans: 32 times.A total of 0.001 g of each sample  was individually weighed alongside 0.1 g of dried KBr. These components were subsequently placed within an onyx mortar and meticulously ground, maintaining a sample to KBr ratio of 1:100. The resulting mixture was then compressed using a tablet press at 20 MPa for a duration of 5 min. The pressed sample tablet was placed into the infrared detector, and the pure KBr tablet was used as a blank . ScanninA 2 g sample was pressed and analyzed with an X-ray diffractometer using Cu-Kα rays as an excitation source. The scanning range was 5°~50° (2θ) and the scanning rate was 4 (°)/min .Double-sided conductive adhesive was securely attached to the sample stage, and a cotton swab was immersed in the sample powder, subsequently affixed to the conductive adhesive. Following this, the sample stage was positioned within the ion sputtering instrument for the purpose of vacuum-coating with gold. This procedure aimed to enhance the conductivity of the sample, thereby facilitating the enhancement of resolution . Probe: The samples (4 mg) were mixed with 15 μL of FITC acetone solution (0.1 mg/mL) protected from light. After 20 min, the suspension was dropped on a slide and observed at an excitation wavelength of 498 nm and an emission wavelength of 517 nm .p < 0.01 or 0.05.All experiments were conducted in triplicate. The results are expressed as the mean ± standard deviation and were statistically analyzed for significance using SPSS software at the significance levels of It should be noted at the outset that due to the high cost of ferulic acid and lipase as well as the high energy consumption due to heating, we prioritized the effects of ferulic acid, lipase and temperature on the degree of substitution.The right amount of ferulic acid had an essential effect on the esterification reaction. According to the principle of chemical reaction equilibrium, increasing the amount of ferulic acid promoted the forward rate of the reaction, thus increasing the amount of product generation . ExcessiSuitable extrusion temperature was favorable for the esterification reaction and could accelerate the pasteurization of corn starch and the increase in active sites. Nevertheless, excessively high extrusion temperatures can result in rapid volume expansion and molecular degradation of corn starch, thereby adversely impacting the esterification reaction. As illustrated in The concentration of lipase played a pivotal role in the esterification reaction involving corn starch, significantly influencing the catalytic efficiency of the entire reaction system. Inadequate lipase concentration failed to ensure the completion of the esterification reaction, while an excessively high lipase concentration led to unwarranted wastage, primarily due to the saturation of the esterification process. As shown in After multiple regression fitting, ANOVA, and significance testing of A significance test for this model yielded the results of the ANOVA in R2 = 0.9923 with p-value < 0.0001, indicating that the regression model was highly significant. And the Lack of fit was not significant , indicating that the predicted values of the regression model fit the actual values with high reliability. From the F-value, it could be seen that the effect of each factor on the degree of substitution was extrusion temperature (B) > lipase addition (C) > ferulic acid addition (A).As shown in From In order to determine the optimal process parameters, the triple quadratic equations were derived by calculating the first partial derivatives of the fitted regression equations, respectively:The optimal process parameters were 8.21% ferulic acid addition (A), 66.49 °C extrusion temperature (B) and 3.16% lipase addition (C). Under these conditions, the degree of substitution was 0.005581. Considering the realistic production, the optimal factor conditions were adjusted to 8.2% ferulic acid addition, 66 °C extrusion temperature and 3.2% lipase addition. After three parallel experiments, the degree of substitution was 0.005581.Based on the aforementioned discoveries, it is evident that the mechanoenzymatic synthesis of starch esters presents significant advantages. The process was characterized by eco-friendly attributes, avoiding the need for organic solvents and elevated temperatures. High selectivity was achieved, minimizing unwanted side reactions. Remarkably controlled under mild conditions, the method exhibited strong adaptability to diverse substrates. Limited catalyst usage reduced costs and waste. The feasibility of precise control over reactions was highlighted, achieved through strategic adjustments of parameters. Furthermore, the scope of application extended across a diverse range of substrates, highlighting its extensive versatility. This methodology serves as an exemplar of the synergy between environmental sustainability, controlled synthesis, and adaptability, thus propelling the development of sustainable and effective avenues within the realm of ester synthesis.As shown in The detergent of the product was subjected to UV full wavelength scanning to identify the presence of ferulic acid in the detergent. The detection results were displayed in The hydrolysate of starch ferulate underwent extraction employing ethyl acetate, and ferulic acid was subsequently characterized through UV spectral scanning. As discerned from −1, which corresponded to the stretching vibration of starch –OH [−1, while the peaks appearing at 1157.462 cm−1, 1082.831 cm−1, and 1000.110 cm−1 corresponded to the C=O peak of starch. For EXCS, the absorption peaks coincide with those of CS, indicating that twin screw extrusion was a physical process that only caused damage to the structure of starch granules and did not involve changes in the moiety. For SF, a new absorption peak appeared at 1726.113 cm−1, which corresponded to the ester carbonyl C=O (1660–1850 cm−1). The remaining three spectra did not show a similar sharp absorption peak type around 1726.113 cm−1, which demonstrated that –OH on the amylose glucose residue (AGU) generated amyl ferulate ester and produced a new functional group (C=O) after twin screw extrusion and enzymatic hydrolysis.FTIR was an important technical tool for the structural characterization of products. According to the different vibration frequencies, the absorption peaks of different groups were analyzed to obtain information about the structure and composition of the substance . The infarch –OH . The peaXRD was an effective tool for assessing the crystallinity of crystals. Typically, diffuse peaks indicated that the sample had an amorphous structure, while sharp peaks represented crystalline material . Figure As depicted in CLSM images of different samples were presented in In this study, starch ferulate was prepared using the extruded enzymatic complex method and the optimum process parameters and structure were optimized and characterized, respectively. The main conclusions were as follows: (1) The optimal process conditions were 8.2% ferulic acid addition, 66 °C extrusion temperature, and 3.2% lipase addition. The degree of substitution of starch ferulate under this condition was 0.005581. (2) The presence of C=O inside the synthesized starch ferulate meant that the synthesis was successful. Its crystal structure was also reconstructed. (3) The twin screw extrusion technique and the esterification reaction could induce an increase in the specific surface area of starch molecules and the exposure of active sites, which was undoubtedly favorable for the synthesis of starch ferulate. This advancement quietly signifies the immense promise of mechanoenzymatic methods in enhancing the swift and eco-friendly synthesis of starch ferulate, unveiling a fresh perspective in ester research. The insights gleaned from this study extend beyond theory, discreetly guiding the evolution and practical application of modified starch esters.


Magnesium–lithium alloys are popular in the lightweight application industry for their very low density. However, as the lithium content increases, the strength of the alloy is sacrificed. Improving the strength of β-phase Mg–Li alloys is urgently needed. The as-rolled Mg-16Li-4Zn-1Er alloy was multidirectionally rolled at various temperatures in comparison to conventional rolling. The results of the finite element simulations showed that multidirectional rolling, as opposed to conventional rolling, resulted in the alloy effectively absorbing the input stress, leading to reasonable management of stress distribution and metal flow. As a result, the alloy’s mechanical qualities were improved. By modifying the dynamic recrystallization and dislocation movement, both high-temperature (200 °C) and low-temperature (−196 °C) rolling greatly increased the strength of the alloy. During the multidirectional rolling process at −196 °C, a large number of nanograins with a diameter of 56 nm were produced and a strength of 331 MPa was obtained. Li further decreases the density of Mg alloys. Additionally, the crystal lattice’s c/a value is decreased; that is, it gradually evolves from the hcp structure to the bcc structure [Magnesium (Mg) alloys have emerged as one of the industry’s most popular options to accommodate the demand for lower weight. Mg alloys have excellent specific strength and stiffness because of their low density. J. Wang et al. studied the use of accumulative roll bonding (ARB) to strengthen the electromagnetic shielding performance of a duplex-phase Mg–9Li–3Al–1Zn alloy, which inspired the future design of lightweight and high-strength electromagnetic shielding structural materials ,3. Becautructure . When pltructure ,8. To obtructure ,11.It is common practice to use plastic deformation methods such as extrusion, rolling, and torsion to improve the strength of β-phase Mg–Li alloys ,12. For The aim of this research, based on the LZE1641 alloy processed by conventional rolling at room temperature, was to further increase the alloy’s strength using multidirectional (MD) rolling and altering the rolling temperature under the condition of the same equivalent strain. The alloy underwent MD rolling as opposed to conventional rolling. The microstructure and mechanical characteristics of the alloy were examined in different states.3. The as-cast specimen was cut into 20 × 20 × 20 mm3 blocks for the ensuing rolling. The samples were subjected to conventional and MD rolling, respectively. The reduction of each pass was 0.8 mm. The specifics are displayed in The composition of the alloy was Mg–16Li–4Zn–1Er (wt.%). The ingots for the alloy were Mg (>99.9 wt.%), Li (>99.9 wt.%), Zn (>99.9 wt.%), and Mg-20 wt.% Er. The ingots were melted in a medium-frequency vacuum induction furnace under the protection of an Ar environment. Then, the melt was poured into a permanent mold. The dimensions of the as-cast specimen were 120 × 110 × 40 mmThe equivalent strain of MD rolling was the same as that of conventional rolling, The samples were rolled at three different temperatures: 25, 200, and −196 °C . SpecimeScanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the specimens’ microstructures. The SEM and TEM equipment models were the FEI Talos F200X G2  and TEM-2100EX , respectively. Wire electrical discharge machining was used to cut off samples with a thickness of 0.5 mm, and then the thin slices were polished with 3000# sandpaper to achieve a thickness of 45 μm. Finally, a wafer of The average grain and second-phase diameters were determined using a mean linear intercept approach.−2 s−1, and the engineering strain was 70%. Five compression samples were made and evaluated for alloy in each state and averaged as the final result.Because of the dimension limitations of rolled samples, particularly the MD rolled samples, tensile tests were challenging to conduct. We used a compression test to compare the strength of the six alloys. In this study, gleeble-3500 hot compression was used to test the compressive properties of the alloys. The size of the compression sample was ϕ8 mm × 12 mm. The location of the compression sample within the rolled sample is depicted in σy) and compressive strengths (σbc) of the alloys are displayed as histograms in The valid portions of the compressive accurate strain-true stress curves are shown in Among various deformation techniques, MD rolling can considerably improve the uniform distribution of primary second-phase fragments with an acceptable size in the matrix. According to the SEM results in In order to remove the interference of the primary second phase on the growth trend of grains and the movement behavior of dislocations, the areas without second-phase fragments were studied using bright-field TEM, as shown in (1)The compressive strength of the alloy is proportional to the grain size. When nanoscale grains form in an alloy, the compressive strength of the alloy dramatically increases.(2)Whether or not the dislocations inside the grains are released does not depend on the temperature or the method of deformation but only depends on the grain size. When the grain size is below a micrometer-scale level, dislocations are prevented from being released and the alloy’s strength is quite high.Based on the results presented above, the following relationships can be described:In conclusion, the DRX grains were responsible for the effects of both rolling temperature and direction on the microstructure. As a result, we split the discussion into two sections: (1) the control of rolling temperature on DRX grains and (2) the control of MD rolling on DRX grains.A is the Arrhenius constant; T is the absolute temperature; and R is the molar gas constant. It is evident that T; that is, elevated rolling temperature causes elevated DRX speed. In this study, the strengthening impact of 25 and 200 °C on the alloy mainly depended on the grain boundary growth brought on by DRX with the proliferation and migration of activated dislocations. The critical driving force needed to trigger DRX in β-phase Mg–Li alloys was low [The initial grain size of Mg–Li alloys is very large, and DRX is frequently seen during plastic deformation. As a result, grain refining is one of the most effective methods of improving strength. Controlling the nucleation and growth of DRX grains is particularly crucial. The DRX speed ( formula :(2)VDRX=High-temperature deformation leads to the storage of energy and is the driving force for the alloy to prematurely reach the critical value. The interface energy of DRX grains in the early process of nucleation is high, and the driving force of grain boundary movement is significant . Driven Cryogenic rolling greatly slowed down DRX in the alloy . Externah is the thickness of the sample.The equivalent stress distribution of the alloy during deformation is depicted in After the current phase of the stress, input was finished. Structures such as DRX, dislocations, and vacancies were formed in the matrix. The non-uniform nucleation features caused variations in the DRX state of the grains, the quantity, the degree of plugging of dislocations, and the concentration of vacancies in various regions of the alloy ,32. The σ) of various microscopic regions and the driving force The relationship between the stress level F( follows :(4)Fσ=σsntations . The disσ A) caused by metal lateral flow when the B-side carried the primary stress input of rolling. Low stress lowers DRX levels. Due to the heterogeneity of the microstructures on the A-side, each microscopic area’s capacity to withstand stress input differed. A region in a low-stress state will absorb additional stress more easily than an area of high-stress concentration (F(σ) < σ A), and weak stress encourages DRX or DRV nucleation and a negligible amount of dislocation proliferation in the matrix. It is not, however, sufficient to achieve the necessary driving power for the significant junction area needed for DRV and dislocation slippage [The contact surface switched from the A-side to the B-side for MD rolling. After initial rolling of the A-side’s surface, the B-side’s surface was the weakly stressed surface. The internal stress concentration of the microstructures on the B-side was low, allowing for higher stress input. The A-side only bore minor stress  surface, the metal flow directions on the A-side and B-side surfaces were opposite to the previous deformation. No macro fractures were discovered in this material due to its extraordinary flexibility. The development of vacancies, on the other hand, was encouraged in the periphery of areas with varied deformation resistance. A sizable portion of vacancies existed as dislocations and DRX nucleation defects, which enhanced the alloy’s boosted strength . AdditioRolling temperature and direction can both be used to maximize the alloy strengthening effect. The alloy gained maximum strength, increasing from 204 to 331 MPa, when MD rolled at −196 °C.Multidirectional rolling broke the second phase of the alloy into finer sized and more uniformly distributed pieces than conventional rolling.A large number of nanograins with a size of about 56 nm appeared in cryogenic multidirectional rolling. This facilitated the contribution of fine grain strengthening.The low temperature effectively maintained the rate of DRX while considerably reducing the DRX grain growth rate, which was far lower than the nucleation rate. The grain refinement and dislocation effects were further optimized.The results of the stress analysis showed that the modification of conventional rolling to MD rolling prevented the relaxation of high-stress areas while reinforcing weak-stress areas. A small amount of force applied in the microscopic area resulted in high-efficiency stress input.