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With the increasing development of underground engineering, various support systems of foundation pits are emerging, and the pile-anchor support system is widely used in deep foundation pit engineering construction. A series of centrifuge model tests for foundation pit excavation was conducted to investigate the deformation laws of the retaining pile and the soil for pile-anchor support system. Compared with the test results of cantilever pile support system, the horizontal displacement of the retaining pile and the settlement of the retained soil significantly decreased, as well as the deformation mode of the pile and the horizontal and vertical distribution of the deformation of retained soil were different for the pile-anchor support system. The movement of retained soil tended towards the vertical due to the increasing deformation of the entire pile, further leading to the variations of the displacement distributions of the soil. The anchor limited the deflection of the pile and thus resulted in a significant reduction of soil deformation. The direction of tangential relative displacement of the anchor and soil changed during the development of the pile top displacement. Accordingly, the pile-anchor-soil interaction was categorized into three different states, which were affected by inclination angles of the anchor as well. Furthermore, it is concluded that there was an optimal inclination angle of the anchor by comparing the test results of pile-anchor support system with various inclination angles.

In the case of nuclear power plants near end of their design life, a reassessment of the performance of safety-related equipment may be necessary to determine whether to shut down or extend the operation of the power plant. Therefore, it is necessary to evaluate the level of performance decline due to degradation. Electrical cabinets, including MCC and switchgear, are representative safety-related equipment. Several studies have assessed the degradation and seismic performance of nuclear power plant equipment. Most of those researches are limited to individual components due to the size of safety-related equipment and test equipment. However, only a few studies assessed the degradation performance of electrical cabinets. The equipment of various nuclear power plants is anchored to concrete foundations, and crack in concrete foundations is one of the most representative of degradation that could be visually confirmed. However, it is difficult to find a study for analysis through testing the effect of cracks in concrete foundations on the response of electrical cabinet internal equipment fixed by anchors. In this study, using a simple cabinet model considering cast-in-place anchor in uncracked and cracked concretes, a tri-axial shaking table tests were performed and the seismic behavior were observed.

Fiber Reinforced Polymer (FRP) composites have been widely used for the repair and strengthening of the reinforced concrete (RC) structures. One of the main problems encountered in these methods is premature debonding failure of externally bonded FRP strip before reaching the strength capacity. In this study, experimental and finite element (FE) studies have been performed to investigate and improve the bonding performance of FRP strips externally bonded to the notched concrete beam surface. Parameters investigated through the experimental studies are (a) bond length, (c) concrete surface quality, (c) BFRP fan anchor, (d) BFRP U wrap anchor, and (e) a new steel anchor type; and that of numerical studies are (a) bond length, (b) concrete surface quality, and (c) a new steel anchor type. Specimens were tested by four-point flexural test under monotonic loading. The change of crack load, ultimate load, deflections, and failure modes were investigated by the results of the experiment and FE analysis. Then, Parametric studies were performed to determine an effective bond length, an efficient thickness of BFRP strips and an effective steel anchor location. According to the findings from the experimental and FE model study, the debonding failure of the non-anchored specimens is caused by the separation of a few millimeter-thick concrete layers from the concrete surface to which the FRP strips are adhered. The results of the experimental study showed that joining the ends of the BFRP strips with steel anchors increased the load-bearing capacity by 24–26% compared to UW and Fan anchors and by 29–43% compared to non-anchored samples; the developed FE model also confirmed these results. In order to effectively utilize the strength capacity of the BFRP strip, anchoring the end of the strip and evenly distributing the load on the BFRP strip proved to be more effective than solely extending the adhesive length.

Stud plays an important role in the connection of steel-concrete composite bridge (SCCB). The stud is under pull-out load in the negative moment zone of SCCB. Engineered Cementitious Composites (ECC) are a new type of materials with tensile strain hardening and multiple cracking behavior to strengthen SCCBs. In this study, the cyclic pull-out effect on the ECC-stud connection was studied through pull-out tests. The stud diameter (d=13/16 mm) and the embedment depth (hef=40/60/80 mm) are included as design parameters, resulting in a total of 18 specimens of six scenarios. The failure mode, load-bearing capacity, and ductility factor of the specimens under cyclic loading are compared with those under monotonic loading, and the stiffness, energy dissipation capacity, and residual displacement of the specimens under cyclic loading are analyzed. Based on the experimental results, under cyclic loading, the concrete cone failure and splitting failure occur, and the threshold of hef/d between the two failure modes is 3.75–4.62, which is smaller than the threshold of the monotonic scenarios. Both concrete and splitting failure modes show ductile failure characteristics because of the bridging effect of fibers in ECC. The load-bearing capacity and ductility factor under cyclic loading are lower than those under monotonic load. This is because, under cyclic loading, the specimens show cumulative damage, which, however, is weakened due to the strengthening effect of ECC. As d and hef increase, the load-bearing capacity, ductility factor, stiffness, and energy dissipation capacity increase correspondingly, and the residual displacement decreases. The stud with a larger d shows a more obvious ductility holding stage.

Background: Perianchor cyst formation (PCF) can occur after arthroscopic rotator cuff repair with poly-L-lactic acid (PLLA) anchors; however, little is known about PCF after all-suture anchor (ASA) use. Methods: We reviewed patients who underwent double-row arthroscopic rotator cuff repair from 2012 to 2017 with ASAs implanted in the medial row and PLLA anchors in the lateral row. We evaluated PCF (graded on magnetic resonance imaging) and compared physical examination and functional surveys between patients with PCF (WC) and without PCF (WoC) at long-term follow-up. Results: Among twenty-two patients (23 shoulders), 93% of PLLA anchors (vs. 79% ASA) displayed a grade 0 PCF, P = .100. No PLLA anchors had a grade 3 or 4 PCF, compared to 11% of ASAs, P = .158. At a mean postoperative follow-up time of 113 weeks, there was no significant difference between WC and WoC cohorts with regard to range of motion, rotator cuff strength, American Shoulder and Elbow Surgeons survey scores, or retear rates. However, the WoC cohort had a significantly higher University of California at Los Angeles shoulder survey score at final follow-up (34.3 WoC vs. 30.9 WC, P = .024). Conclusion: No difference was found in PCF between ASAs and PLLA anchors. At long-term follow-up, WoC patients had significantly improved functional outcome scores, based on the University of California at Los Angeles survey, but equivalent range of motion and rotator cuff strength examinations compared with WC patients.

Purpose: To explore whether patient position influences a surgeon’s ability to accurately judge anchor position on the glenoid. Materials and Methods: Two anchors were inserted into the glenoid of 8 shoulders. Arthroscopic videos were taken from 3 views (posterior beach chair [pBC], posterior lateral decubitus [pLD], and anterosuperolateral decubitus [asLD]). The shoulders were disarticulated to identify “true” anchor position. Seventeen shoulder surgeons reviewed the videos and indicated anchor positions using the “clock face” method. Accuracy was measured within tolerances, ranging from zero (exact), 0.5 (half-hour), 1.0, and 1.5 hours of “true” position. Intra- and inter-rater agreement was calculated. Post hoc analyses explored for bias dependent on surgical side. Results: The overall accuracy was 34.0%. At tolerances of 0.5, 1.0, and 1.5 hours, accuracy increased to 82.4%, 95.4%, and 98.0%. With a 30° scope, identification of exact position was more accurate in pBC than pLD (odds ratio [OR] = 1.397; P = .029) but not asLD (OR =1.341; P = .197). At a tolerance of 0.5 hour, the 30° scope was more accurate in pBC than both pLD (OR = 1.444; P = .011) and asLD (OR = 1.728; P = .009). In left shoulders, anchors were perceived as more inferior than true position in asLD and pLD. In right shoulders, anchors were perceived as more superior than true position from pBC and pLD. Inter- and intrarater agreement were highest in pBC with a 30° scope (30° scope weighted kappa = 0.783 and 70° scope weighted kappa = 0.853, respectively). Conclusion: Judgment of anchor position on video is most accurate in a pBC view. Inter- and intrarater reliability were also highest from a pBC view.

Recurrent subluxation and dislocation of peroneal tendons due to torn peroneal retinaculum and supporting ligaments are problematic. Surgical management for retinaculum repair include tendon rerouting, anatomic reattachment of the retinaculum, and fibular groove deepening. However, in cases of severe degeneration of the retinaculum and ankle instability, supplementation or augmentation of the retinaculum is needed. Suture tape has been successfully used for anterior talofibular ligament (AFTL) and spring ligament repairs in foot and ankle procedures. In this study, we present a case that illustrates a novel and successful utilization of a fiber tape anchor system in repairing and augmenting an extremely damaged peroneal retinaculum. To our knowledge, this is the first study that describes this application.

Background: The severity of hallux valgus (HV) deformity is associated with recurrence after corrective surgery because of the degenerative change of the medial capsule including the medial collateral ligament (MCL) at the metatarsophalangeal joint. This study aimed to assess the effectiveness of the MCL augmentation using a suture tape anchor of the recurrence of HV and to evaluate the histological changes of the medial joint capsule in HV patients., Methods: Thirty-four feet with severe hallux valgus were included and divided into 2 groups. Seventeen feet had the MCL reconstruction using suture tape anchor with a combination of the corrective osteotomy as the suture tape group (mean age, 64.0 years), and other seventeen feet had the corrective osteotomy without MCL reconstruction as the control group (mean age, 62.0 years). HV angle (HVA) and intermetatarsal angle (IMA) on the weight-bearing radiograms and the Japanese Society for Surgery of the Foot (JSSF) score in both groups were compared at the final follow-up. The medial capsule was harvested from other 20 feet with HV and the relationship between the severity of HV and the histological findings was analyzed., Results: HVA, IMA, and JSSF scores in both groups were significantly improved from preoperatively to the final follow-up (P < 0.01). At the final follow-up, HVA in the suture tape group (9.2°) was significantly smaller than that in the control (15.4°) (P < 0.01). There were no significant differences in the IMA and the JSSF score at the final follow-up between both groups. Histological scores in HV with ≥40° HVA was significantly worse than those in <40°., Conclusion: The medial joint capsule in severe HV deformity showed the degenerative change and the MCL reconstruction using suture tape combined with osteotomy provides a strong medial constraint to prevent the recurrence of the deformity in severe hallux valgus., Level of Clinical Evidence: 3., Competing Interests: Declaration of competing interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright © 2023 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Experimental and numerical investigations have been carried out on behavior of pullout resistance of embedded circular plate with and without geogrid reinforcement layers in stabilized loose and dense sands using a granular trench. Different parameters have been considered, such as the number of geogrid layers, embedment depth ratio, relative density of soil and height ratio of granular trench. Results showed that, without granular trench, the single layer of geogrid was more effective in enhancing the pullout capacity compared to the multilayer of geogrid reinforcement. Also, increasing the soil density and embedment depth ratio led to an increase in the uplift capacity. When soil was improved with the granular trench, the uplift force significantly increased. The granular trench improved the uplift load in dense sand more, as compared to the same symmetrical plate embedded in loose sand. Although it was observed that, in geogrid-reinforced granular trench condition, the ultimate pullout resistance at failure increased as the number of geogrid layers increased up to the third layer, and the fifth layer had a negligible effect in comparison with the third layer of reinforcement. Finite element analyses with hardening soil model for sand and CANAsand constitutive model for granular trench were conducted to investigate the failure mechanism and the associated rupture surfaces utilized. The response of granular material in the proposed model is an elastoplastic constitutive model derived from the CANAsand model, which uses a non-associated flow rule along with the concept of the state boundary surface possessing a critical and a compact state. It was observed that the granular trench might change the failure mechanism from deep plate to shallow plate as the failure surface can extend to the ground surface. The ultimate uplift capacity of anchor and the variation of surface deformation indicated a close agreement between the experiment and numerical model.

Objective: The objective of this study was to investigate the mechanics of ventricular anchor for heart valve repair or replacement. Methods: Thirteen anchors were designed based on six geometric parameters of the anchor teeth: width, thickness, root length, radius of curvature, tip angle, and tip length. Finite element method was applied to simulate the process of the anchor compressing into a sheath. The Von-Mises strain, peak pulling force, and bite depth were evaluated. An experiment was performed to validate the simulation. Results: The maximum Von-Mises strain was at the contact region of the anchor in a sheath where the teeth were compressed against one another and were distorted. The maximum strain increased with an increase in tooth width, thickness, radius of curvature and tip angle. The peak pulling force increased as tooth thickness and width increased, and radius of curvature decreased. Both the radial and axial bite depths increased with an increase in the tip length at the tip length≥3 ​mm. The radial bite depth increased with an increase in the radius of curvature. Conclusion: 1) the maximum strain depends primarily on the tooth width, thickness, radius of curvature and tip angle; 2) the peak pulling force depends primarily on the tooth width, thickness, radius of curvature; 3) the axial bite depth depends primarily on the tip length at the tip length≥3 ​mm. The radial bite depth depends on the radius of curvature and the tip length at the tip length >3 ​mm. The study provides guidance for ventricular anchor design.

Objectives: To compare anchored discrete choice experiment (DCE) utility values using own versus others' time trade-off (TTO) responses in the valuation of SF-6Dv2., Methods: A representative sample of the general population was recruited in China. Through face-to-face interviews, both DCE and TTO data were collected from a randomly selected half of the respondents (own TTO sample), whereas only TTO data were collected from the other half (others' TTO sample). Conditional logit model was used to estimate DCE latent utilities. Three anchoring methods, including using the observed and the modeled TTO values for the worst state, and mapping DCE values onto TTO, were used to scale the latent utilities to health utilities. Prediction accuracy was assessed using intraclass correlation coefficient, mean absolute difference, and root mean squared difference compared with the mean observed TTO values between the anchoring results using the own versus others' TTO data., Results: Demographic characteristics were comparable between the own TTO sample (n = 252) and the others' TTO sample (n = 251). The mean (SD) observed TTO value for the worst state was -0.259 (0.591) for the own TTO sample and -0.236 (0.616) for the others' TTO sample. Anchoring DCE using own TTOs consistently showed a better prediction accuracy than using others' TTOs across the 3 anchoring methods in terms of the intraclass correlation coefficient (0.835-0.873 vs 0.771-0.804), mean absolute difference (0.127-0.181 vs 0.146-0.203), and root mean squared difference (0.164-0.237 vs 0.192-0.270)., Conclusion: When anchoring DCE-derived latent utilities onto the health utility scale, respondents' own TTO data would be preferred to TTO data obtained from a different sample., (Copyright © 2023 International Society for Pharmacoeconomics and Outcomes Research, Inc. Published by Elsevier Inc. All rights reserved.)

Background: A variety of different techniques or methods for treatment of tibial eminence fracture (TEF) have been reported, but there is still controversy on the optimum choice for treating TEFs. The aim of the current work was to compare the clinical outcomes of arthroscopic cannulated screw fixation and a new arthroscopic anchor fixation technique for tibial eminence fracture., Methods: We included 69 isolated tibial eminence fracture patients from June 2012 to February 2017; 36 patients received the cannulated screw fixation and 33 received the transosseous anchor knot (TAK) fixation under arthroscopy. The two techniques were performed by two different high-volume surgeons. The clinical efficacies of the two techniques were assessed by radiographs, extension deficit, flexion deficit, anterior drawer test (ADT), Lachman test, Lysholm scores and International Knee Documentation Committee (IKDC) scores in follow ups., Results: Patients were followed up for 35.8 months on average (range, 24-54 months). There were 40 (58%) males and 29 (42%) females included, and four (6%) patients were ＜18 years old. Asymptomatic grade II laxity was found in two patients in the CS group and three patients in the TAK group from the results of Lachman test. Postoperative radiographs in all patients showed anatomic reductions and bony unions were achieved within 12 weeks. There were no significant differences in extension deficit, flexion deficit, ADT, Lachman test, Lysholm scores and IKDC scores between groups (P > 0.05)., Conclusions: The TAK technique shows satisfactory clinical and radiological outcomes equal to the cannulated screw fixation, which is applicable for TEFs as a reliable effective method., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

The adult Drosophila intestinal epithelium must be tightly regulated to maintain regeneration and homeostasis. The dysregulation of the regenerative capacity is frequently associated with intestinal diseases such as inflammation and tumorigenesis. Here, we showed that the G protein-coupled receptor Anchor maintains Drosophila adult midgut homeostasis by restricting Jun-N-terminal kinase (JNK) and Notch pathway activity. anchor inactivation resulted in aberrant JNK pathway activation, which led to excessive enteroblast (EB) production and premature enterocyte (EC) differentiation. In addition, increased Notch levels promoted premature EC differentiation following the loss of anchor. This defect induced by the loss of anchor ultimately caused sensitivity to stress or environmental challenge in adult flies. Taken together, our results demonstrate that the activity of anchor is essential to coordinate stem cell differentiation and proliferation to maintain intestinal homeostasis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Lateral-row (LR) arthroscopic biceps tenodesis (BT) has been described as a technique using an LR rotator cuff repair (RCR) anchor for biceps fixation. This technique has not been compared with other BT techniques. The purpose of this study was to compare the clinical outcomes of patients undergoing a suprapectoral "in-the-groove" arthroscopic BT and patients treated with an LR tenodesis performed in conjunction with arthroscopic RCR., Methods: Patients undergoing arthroscopic BT in the setting of an arthroscopic RCR were evaluated preoperatively and at a minimum of 12 months' follow-up. Patients who underwent an in-the-groove BT were matched 1:1 to patients who underwent an LR BT based on age at surgery and size of the rotator cuff tear using the Patte classification. Comparisons made included age, sex, body mass index, patient-reported outcome measures, range of motion, and patient satisfaction., Results: There were 82 patients (41 in each group) who met the inclusion criteria, with an average follow-up period of 33 months and average age of 61 years. By use of the Patte classification, there were 20 matched pairs with stage 1 tears, 11 matched pairs with stage 2 tears, and 10 matched pairs with stage 3 tears. Comparisons of the 2 cohorts revealed no differences in preoperative or postoperative motion, patient-reported outcome measures, or patient satisfaction. Furthermore, no differences were found in overall improvements in motion or outcome measures, as well as overall satisfaction., Conclusions: Patients undergoing simultaneous RCR and BT demonstrate similar patient-reported and objective outcomes for both LR tenodesis and in-the-groove tenodesis techniques., (© 2019 The Author(s).)

Objective: The biomechanical study was performed to investigate the effect of a novel pedicle screw anchor in increasing the pullout strength of pedicle screws., Methods: Ten lumbar vertebral bodies with a weighted average T-score of -2.13 were used. Pedicle screws of 4.5 mm diameter and 25 mm length were inserted in to one pedicle randomly and matched with an anchor in the corresponding pedicle. Fatigue testing was performed by applying an axial load of ±200N to the screw tulip, along the axis of the rod, at a rate of 0.5 Hz for 1,000 cycles. After fatigue loading was completed, all screws underwent axial pullout testing at a rate of 0.1 mm/sec until failure. A paired two sample for means t-test was performed to determine a significant difference between the two groups (p ≤ 0.05)., Results: Following fatigue testing, the axial displacement at the 1,000 cycle point for the anchor and non-anchor group was 1.4 ± 0.7mm and 2.9 ± 1.2mm, respectively. The anchor group had significantly lower axial displacement compared to the non-anchor group (p ≤ 0.01). The group with the anchor reached an average maximum load of 702 ± 373N. The average yield load for the non-anchor group was 421 ± 293N. The anchor group yield load was significantly greater than the non-anchor group (p ≤ 0.01)., Conclusions: A novel anchor for standard pedicle screws resulted in significantly less axial movement during fatigue and a greater failure force compared a screw with no anchor. The anchor may provide a stronger bone-to-screw interface, than a non-anchor screw, without the complications of cement augmentation., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objectives: To evaluate the responsiveness of generic and mapped preference-based measures based on the anchor of global change in health condition of colorectal cancer (CRC) patients., Study Design and Setting: A baseline sample of 333 Chinese CRC patients was recruited between September 2009 and July 2010 and was surveyed prospectively at 6-month follow-up. Preference-based indices were derived from the generic SF-6D measure (SF-6DDirect), from the Short Form-12 (SF-6DSF-12), and mapped from the condition-specific Functional Assessment of Cancer Therapy-Colorectal (SF-6DFACT-C). Responsiveness of three measures was assessed using standardized effect size, standardized response mean, responsiveness statistic, and receiver operating characteristic (ROC) curve analysis., Results: The SF-6DSF-12 and SF-6DFACT-C indices were significantly more responsive to detect positive changes than the SF-6DDirect index in improved groups. In worsened group, the SF-6DDirect and SF-6DFACT-C indices showed significant decline from baseline to 6-month follow-up. The areas under the ROC curve for SF-6DDirect and SF-6DFACT-C indices were not statistically different from 0.7. The SF-6DFACT-C index was more responsive to changes in health status compared with other indices., Conclusion: Direct SF-6D measure was more responsive than mapped preference-based measures in improved group but the direction was reversed in worsened group. The use of a preference-based index mapped from a condition-specific measure captures both negative and positive important changes among CRC., (Copyright © 2014 Elsevier Inc. All rights reserved.)