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Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.

Background: Capsulorrhaphy restricts the motion of the first metatarsophalangeal joint (MTPJ) in hallux valgus surgery. However, changes in motion of the first MTPJ immediately after surgery that resulted from different capsulorrhaphy methods have not been compared. The primary aim of this study was to compare the immediate effect of Y-shaped and inverted L capsulorrhaphy methods on the range of motion (ROM) of the first MTPJ. Methods: Y-shaped and inverted L capsulorrhaphies were performed on 16 human cadaveric feet. Passive dorsiflexion and plantarflexion of the first MTPJ were then compared preoperatively and postoperatively. Results: In this cadaveric study, the inverted L capsulorrhaphy method led to a ROM loss in the first MTPJ; the joint stiffness from the Y-shaped capsulorrhaphy is significantly less than that from the inverted L capsulorrhaphy. Conclusions: The inverted L capsulorrhaphy may lead to a ROM loss in the first MTPJ immediately after surgery. We recommend that surgeons close the capsule of the first MTPJ with a Y-shaped capsulorrhaphy, which is less likely to result in a ROM loss in the first MTPJ in the early postoperative period.

Background Several approaches to spring ligament reconstruction have been reported. However, a comparative study of nonanatomic and anatomic techniques with respect to biomechanical responses, such as kinematics and contact characteristics, has not been previously performed via a finite element analysis. The purpose of this study was to evaluate the biomechanical results of such spring ligament reconstructions via a finite element analysis. Methods A three-dimensional finite element model of the foot was developed and validated, and four reconstruction methods were simulated. The talonavicular dorsiflexion and abduction, hindfoot valgus, and contact characteristics in the Chopart joints were quantified in each model. Results Nonanatomic reconstructions corrected the talonavicular and hindfoot deformities to a greater extent than the anatomic reconstructions. The anatomic techniques also corrected the abduction and dorsiflexion deformities, although they presented insufficient power to correct for hindfoot valgus. None of the procedures restored the contact characteristics of the talonavicular and calcaneocuboid joints to those of a normal condition. Conclusion Nonanatomic reconstruction of the spring ligament complex provided the greatest correction for midfoot and hindfoot misalignments in flatfoot. Severe deformities with large amounts of midfoot pronation and hindfoot valgus may be better treated with nonanatomic reconstruction methods. The spring ligament reconstruction method may mitigate the need for nonanatomic bony procedures associated with complications and allows for the preservation of the triple joint complex.

Background Postoperative wound complication is a major risk factor for the development of Periprosthetic joint infection, thus, it is very important to manage surgical wounds. We innovatively invented a new dressing system to reduce the occurrence of postoperative wound complications and improve the quality of life of patients after an total hip arthroplasty. Besides, this study confirmed the clinical safety and feasibility of the newly invented dressing system. Methods A total of 120 patients who underwent primary unilateral total hip arthroplasty were enrolled in this study. The data collected included the number of dressing changes, costs of the dressings, postoperative hospital stay, The Visual Analogue Scale (VAS) score, The Harris Hip Score (HHS), ASEPSIS score, The Stony Brook Scar Evaluation Scale (SBSES), wound complications, the frequency of showers and satisfaction. Data were statistically analyzed. Results The average number of dressing changes was 0.74 ± 0.46, while the average postoperative hospital stay was 3.67 ± 0.97 days. The average cost of the new dressings throughout a treatment cycle was 57.42 ± 15.18 dollars. The VAS score decreased from 5.63 ± 1.09 before the operation to 0.88 ± 0.54 one month after the operation. The HHS score increased from 70.18 ± 7.84 before the operation to 80.36 ± 4.08 one month after the operation. The results of the four indexes of the ASEPSIS score were all 0. The SBSES score was 3.55 ± 0.61 at two weeks after the operation, and 4.38 ± 0.71 at one month after the operation. No wound complications were recorded until one month after the operation when the satisfaction rate was 92.53 ± 3.62%. Conclusion In this study, we have invented a new dressing system for surgical wounds after total hip arthroplasty and confirmed its clinical safety and feasibility. Trial registration Chinese Clinical Trial Registry, ChiCTR2000033822. Registered 13 June 2020, http://www.chictr.org.cn/showproj.aspx?proj=54735

Inorganic semiconductor-based microscale light-emitting diodes (micro-LEDs) have been widely considered the key solution to next-generation, ubiquitous lighting and display systems, with their efficiency, brightness, contrast, stability, and dynamic response superior to liquid crystal or organic-based counterparts. However, the reduction of micro-LED sizes leads to the deteriorated device performance and increased difficulties in manufacturing. Here, we report a tandem device scheme based on stacked red, green, and blue (RGB) micro-LEDs, for the realization of full-color lighting and displays. Thin-film micro-LEDs (size ∼100 μm, thickness ∼5 μm) based on III–V compound semiconductors are vertically assembled via epitaxial liftoff and transfer printing. A thin-film dielectric-based optical filter serves as a wavelength-selective interface for performance enhancement. Furthermore, we prototype arrays of tandem RGB micro-LEDs and demonstrate display capabilities. These materials and device strategies provide a viable path to advanced lighting and display systems.

Osteoporosis is the most prevailing primary bone disease and a growing health care burden. The aim of this study was to clarify the functional roles and mechanisms of the circ-ITCH regulating osteogenic differentiation of osteoporosis. Circ-ITCH and yes-associated protein 1 (YAP1) levels were downregulated, but the miR‐214 level was upregulated in osteoporotic mice and patients. Knockdown of circ-ITCH inhibited the alkaline phosphatase (ALP) activity, mineralized nodule formation, and expression of runt-related transcription factor 2 (RUNX2), osteopontin (OPN), and osteocalcin (OCN) during osteogenic induction. Furthermore, miR-214 was a target of circ-ITCH, knockdown of miR-214 could impede the regulatory effects of sh-circ-ITCH on osteogenic differentiation. Moreover, miR-214 suppressed hBMSCs osteogenic differentiation by downregulating YAP1. Finally, in vivo experiments indicated that overexpression of circ-ITCH could improve osteogenesis in ovariectomized mice. In conclusion, circ-ITCH upregulated YAP1 expression to promote osteogenic differentiation in osteoporosis via sponging miR-214. Circ-ITCH could act as a novel therapeutic target for osteoporosis.

To investigate the feasibility of quantifying the chemical composition of coronary artery plaque in terms of water, lipid, protein, and calcium contents using dual-energy computed tomography (CT) in a simulation study. A CT simulation package was developed based on physical parameters of a clinical CT scanner. A digital thorax phantom was designed to simulate coronary arterial plaques in the range of 2-5mm in diameter. Both non-calcified and calcified plaques were studied. The non-calcified plaques were simulated as a mixture of water, lipid, and protein, while the calcified plaques also contained calcium. The water, lipid, protein, and calcium compositions of the plaques were selected to be within the expected clinical range. A total of 95 plaques for each lesion size were simulated using the CT simulation package at 80 and 135 kVp. Half-value layer measurements were made to make sure the simulated dose was within the range of clinical dual energy scanning protocols. Dual-energy material decomposition using a previously developed technique was performed to determine the volumetric fraction of water, lipid, protein, and calcium contents in each plaque. For non-calcified plaque, the total volume conservation provides the third constrain for three-material decomposition with dual energy CT. For calcified plaque, a fourth criterion was introduced from a previous report suggesting a linear correlation between water and protein contents in soft tissue. For non-calcified plaque, the root mean-squared error (RMSE) of the image-based decomposition was estimated to be 0.7%, 1.5%, and 0.3% for water, lipid, and protein contents, respectively. As for the calcified plaques, the RMSE of the 5mm plaques were estimated to be 5.6%, 5.7%, 0.2%, and 3.1%, for water, lipid, calcium, and protein contents, respectively. The RMSE increases as the plaque size reduces. The simulation results indicate that chemical composition of coronary arterial plaques can be quantified using dual-energy CT. By accurately quantifying the content of a coronary plaque lesion, our decomposition method may provide valuable insight for the assessment and stratification of coronary artery disease.

The energy density of commercial Li-ion batteries (LIBs) is limited by the specific capacity of intercalation-type cathodes. The Li-O2 batteries based on the conversion reaction of oxygen cathodes can deliver the superhigh specific capacity. Herein, the Li-rich layered-oxide 0.5Li2MnO3·0.5LiNi0.54Co0.16Mn0.16O2 (5/5 LLO) cathodes have been combined with O2 cathodes, in order to examine their synergistic effect on cell performance. It is found that the hybrid cells deliver the discharge capacity of 458 mAh [Formula: see text] at approximately 0.2 C, compared with the specific capacity 200 mAh [Formula: see text] at 0.2 C of 5/5 LLO in LIB. Meanwhile, the cycle life of Li-O2 batteries under 100% depth of discharge increases from a few cycles to more than 20 cycles, attributed to the transition of Ni2+ to Ni4+ upon charging that promotes decomposition of reaction products Li2O2 and by-products Li2CO3. These results demonstrate that the hybrid Li-ion/Li-O2 battery is a powerful way for combining advantages of the intercalation and conversion-type cathodes, promising for construction of future high-energy batteries.

Internet gaming disorder (IGD) is becoming a prevalent mental health concern around the world. However, the relationship among brain gray matter volume (GMV), emotion induced by decision-making and the level of reflection in IGD participants has not been fully elucidated to date. The current study aimed to explore this issue by combining a sequential decision task and voxel-based morphometry. Twenty-six IGD participants and 28 demographically matched healthy controls were recruited. After collecting Rumination-Reflection questionnaire data and high-resolution T1-weighted MRI data, participants were asked to complete a sequential decision task. The results demonstrated that compared to healthy controls, IGD participants exhibited significantly decreased GMV in the superior frontal gyrus (SFG). Moreover, GMV in the SFG of IGD participants fully mediated the impact of reflection level on the emotion of loss outcome during the sequential decision task. These results indicate that IGD is associated with reduced GMV in the SFG, and this structural change in IGD contributes to a particular relationship between the level of reflection and regret emotion for loss outcome in the sequential decision task.

BackgroundA simulation and model (SM) teaching aid using 3D printing was developed to improve a training course for total hip arthroplasty of adult developmental dysplasia of the hip (adult DDH-THA). We named this new method Surgery Simulation Teaching based on a Real Reconstruction Aid (RRA-SST). A prospective randomized comparison was performed with the traditional surgical live teaching method to evaluate the training effectiveness of RRA-SST for adult DDH-THA.MethodsTwenty-six trainees, who were already practicing but were not experienced, participated in the study. We randomly divided the trainees into two groups: Group A (n = 13) received RRA-SST and group B (n = 13) received traditional surgical live teaching. A surgery simulation test and a questionnaire were used for evaluation. Next, each group received training with the other teaching method, and then the test and questionnaire were used again for evaluation.ResultsAfter the first test, the RRA-SST method was shown to produce better results than the traditional surgical live teaching method. After the second test, the results showed the training effect in both groups reached the same level, which was level as Group A RRA-SST results. Analysis of the questionnaire results showed that the training effect of RRA-SST was higher than that of traditional surgical live teaching, from multiple perspectives.ConclusionsThe use of RRA-SST improved participant performance according to simulation assessment. RRA-SST can be helpful for trainees who are already practicing but not experienced when developing proficiency in adult DDH-THA surgical techniques.

Previous research has demonstrated that some false recognitions are accompanied by retrieval of contexts in which the corresponding semantic associates were presented during the study phase. What kind of neural processes support context retrieval in false recognition? Using functional MRI (fMRI), we tested the hypothesis that context retrieval in false recognition might be supported by brain areas in the core recollection network which also support context retrieval in true recognition. During the study, lists of semantically associated words were presented together with scene pictures that served as contexts. During test, participants judged whether the presented word was old or new. If old, they judged which scene picture was its context and rated memory strength for the context. The results revealed that several regions in the core recollection network, including the bilateral hippocampus, left angular gyrus, and left anterior cingulate cortex, showed greater activations for true recognitions with strong context memory than those with weak context memory. More importantly, these same regions also showed greater activations for false recognitions with strong context memory than those with weak context memory. These findings helped account for why some false recognitions are vivid and accompanied by retrieval of context.

Background Traditional methods for minimally invasive internal fixation (MIIF) of calcaneal fractures require extensive intraoperative fluoroscopy, and fracture recovery is usually not ideal. We developed a new surgical procedure using digital surgical simulation and constructed a patient-specific instrument (PSI) for calcaneal fracture that we used during the operation. This study investigated whether PSI-assisted MIIF of calcaneal fracture enables rapid and accurate execution of the preoperative plan. Methods We retrospectively analyzed patients with Sanders type III or IV fresh calcaneal fractures who had undergone PSI-assisted MIIF at our hospital from January 2016 to December 2018. We analyzed perioperative data including intraoperative fluoroscopy time, concurrence of internal fixation actual usage (IFAU) with the preoperative plan, surgery time, and complications. We also compared pre- and postoperative actual measurements from X-ray radiographs and computed tomography images including Böhler, Gissane, and calcaneus valgus angles; subtalar joint width; and calcaneal volume overlap ratio with the preoperative design. All patients had been followed up and their American Orthopedic Foot and Ankle Score (AOFAS) score was available. Results Mean intraoperative fluoroscopy time was 3.95 ± 1.78 h; IFAU in 16 patients (16 ft) was the same as the preoperative plan; mean surgery time was 28.16 ± 10.70 min; and none of the patients developed complications. Böhler, Gissane, and calcaneus valgus angles and subtalar joint width did not differ between pre- and postoperative plans; however, the actual preoperative values of each of these parameters differed significantly from those measured postoperatively. The calcaneal volume overlap ratio with the preoperative design was 91.2% ± 2.3%. AOFAS scores increased with time, with significant differences in the score at each time point. Conclusions The newly developed PSI-assisted calcaneal fracture MIIF method can rapidly and accurately execute the preoperative plan.

Background Over the past seven years, our team has designed a simulated operation combined with patient-specific instrumentation (SO-PSI) assisted supramalleolar osteotomy (SMOT) method and applied it in the clinic. This study aimed to evaluate the differences between SO-PSI technology and conventional operation (CO) technology for SMOT in preoperative planning, intraoperative application, and postoperative curative effect. Methods We retrospectively analyzed SMOT data collected from our hospital between October 2014 and December 2018. Patients (n = 28) were enrolled and divided into CO (n = 17) and SO-PSI (n = 11) groups; mean follow-up time was 33.4 (range, 13 to 59) months. We statistically analyzed and compared perioperative data, accuracy of preoperative planning, and intraoperative application; difference between pre- and post-operative radiologic ankle angles; and changes in American Orthopaedic Foot & Ankle Society (AOFAS) score, visual analogue scale (VAS) score, range of ankle motion, and Takakura stage after surgery. Results All ankle alignments and positions were recovered for both groups. Compared with the CO group, the SO-PSI group had a shorter mean operating time and postoperative hospital stay, a decreased number of fluoroscopy examinations, lower albumin reduction, longer preoperative planning time and preoperative hospital stay, and increased hospitalization expenses. In the SO-PSI group, comparison of ankle angles at preoperative planning and postoperatively revealed good correlation, while this was not the case in the CO group. Mean tibial ankle center discrepancy for the SO-PSI group was 1.86 ± 1.06 mm. On follow-up, all radiologic parameters for the two groups improved significantly; however, the improvement of the tibial anterior surface angle and tibiotalar tilt angle for the SO-PSI group were more obvious than those for the CO group; AOFAS score, VAS score, ankle range of motion, and Takakura stage improved after surgery in both groups; however, the improvements in the SO-PSI group were greater than those in the CO group overall. Conclusions SO-PSI technology can facilitate accurate and rapid preoperative planning for SMOT. In general, compared with conventional technology, SO-PSI has advantages for preoperative planning, intraoperative application, and postoperative curative effect.

Background: Almost all of the traditional calcaneal fracture minimally invasive internal fixations (MIIF) require a lot of intraoperative fluoroscopy, moreover, the fracture recovery of many patients is not considered ideal. Therefore, we designed a new surgical procedure through the digital surgical simulation and made patient-specific instrument (PSI) for calcaneal fracture patients before surgery, and then we manage the operation through the assistance of PSI during the whole process. The purpose of this study is to verify whether the PSI assisted calcaneal fracture minimally invasive internal fixation can carry out preoperative plan accurately and quickly. Methods: We retrospectively analyzed the Sanders type III or IV fresh calcaneal fracture patients who had been performed MIIF assisted by the PSI in our hospital during January 2016 to December 2018. We collected and analyzed perioperative data including intraoperative fluoroscopy times, whether the internal fixation actual usage (IFAU) same as preoperative plan, surgical time and situation of complication; and collected and analyzed the data of preoperative actual measurement, preoperative-plan and postoperative actual measurement from X-rays and CT, including Böhler angle, Gissane angle, subtalar joint width, calcaneus valgus angle and calcaneal volume overlapping ratio. All patients had been followed up and their AOFAS score had been recorded. Then we performed statistical analyses. Results: The intraoperative fluoroscopy times was 3.95±1.78, the condition of IFAU in 16 patients (16 feet) was the same as preoperative plan, the surgery time was 28.16±10.70 min, no patients developed complications. The preoperative plan Böhler angle, Gissane angle, subtalar joint width and calcaneus valgus angle were not significant different from the postoperative; the preoperative Böhler angle, Gissane angle, subtalar joint width and calcaneus valgus angle were all significant different from the postoperative. The calcaneal volume overlapping ratio with preoperative design was 91.2±2.3%. The AOFAS score of all patients gradually increased as time goes on, and difference of the AOFAS scores between all time-points were significant. Conclusions: The new patient-specific instrument assisted calcaneal fracture minimally invasive internal fixation can carry out the preoperative plan accurately and quickly.

Background: Over the past seven years, our team has designed a simulated operation combines patient-specific guide (SO-PSI) assisted supramalleolar osteotomy (SMOT) method and applied it to the clinic. This study aimed to determine the difference between SO-PSI technology and conventional operation (CO) technology for SMOT in preoperative planning, intraoperative application and postoperative curative effect. Methods: We retrospectively analyzed the data of SMOT in our hospital between October 2014 and December 2018; 28 patients were enrolled and divided into CO group (n=17) and SO-PSI group (n=11); the mean follow-up time was 33.4 (range, 13 to 59) months. We analyzed and compared perioperative data, accuracy of preoperative planning and intraoperative application, difference between pre- and post-operative of radiologic ankle angles, and change of AOFAS score, VAS, range of motion of ankle and Takakura stage after operation. Then we performed statistical analyses. Results: All ankle alignments and positions of two groups have been recovered. Compared with CO group, SO-PSI group has a shorter operative time and a postoperative hospital stay, a decreased number of fluoroscopies and a reduction of albumin, a longer preoperative planning time and a preoperative hospital stay and an increased hospitalization expenses. In SO-PSI group, the ankle angles between preoperative planning and postoperative shown good correlation, but not in CO group; the mean tibial ankle center discrepancy of SO-PSI group was 1.86±1.06 mm. After follow-up, all radiologic parameters of two groups significantly improved, but the improvement of tibial anterior surface angle and tibiotalar tilt angle of SO-PSI group were more obvious than that of CO group; AOFAS score, VAS, range of motion of ankle and Takakura stage of two groups improved after operation; but overall the improvements of SO-PSI group were better than the CO group. Conclusions: SO-PSI technology can carry out the preoperative plan accurately and quickly in SMOT; In general, compared with the conventional technology, SO-PSI technology has advantages in preoperative planning, intraoperative application and postoperative curative effect. Keywords: Supramalleolar osteotomy; Simulated operation; Patient-specific guide; Accuracy of preoperative planning; Practicability of application

Background A great deal of research suggests that arthroscopic ankle fusion (AAF) has advantages over open ankle fusion (OAF), but these outcomes would be imprecise because of a selection bias. The purpose of this study is to verify which is better for ankle fusion, AAF or OAF. We regrouped the OAF group into two subgroups according to whether the osseous operation type is the same as AAF group. The goal is to minimize the impact of disease severity, thereby reducing selection bias to some extent. Methods We retrospectively analyzed the data of ankle fusion in our hospital between July 2015 and October 2018. Forty-three patients were enrolled and divided into AAF group (n = 17) and OAF group (n = 26). In order to eliminate selection bias, we divided OAF group into complex osseous operation subgroup (COO subgroup) (n = 15) and simple osseous operation subgroup (SOO subgroup) (n = 11). The osseous operation type of SOO subgroup is the same as AAF group. Then, we compared the differences between these groups. All patients were followed up at least 1 year after operation. We analyzed data, including etiology composition, surgical time, intra-op blood loss, reduction of albumin, total hospital stays, union time, fusion situation, complications, radiological examination, functional score, and questionnaire survey. Then we performed statistical analyses. Results We found that the etiological components of AAF group and OAF group were different; the etiological components of AAF group and SOO subgroup were similar. We found that AAF group has advantages over OAF group and COO subgroup in general. However, except in terms of surgical trauma, hospital stays, and short-term complications occurred, the AAF group has not obvious advantages over SOO subgroup, including intra-op blood loss, fusion condition, postoperative function score, and postoperative patient satisfaction; and AAF group need more surgical time than the SOO subgroup. Conclusions The arthroscopic ankle fusion can bring a good curative effect; however, if the osseous operation type is the same, the arthroscopic ankle fusion only has a limited advantage over the traditional open operation in perioperative soft tissue protection and enhanced recovery after surgery.

Background: A great deal of research suggests that arthroscopic ankle fusion (AAF) has advantages over open ankle fusion (OAF), but these outcomes would be imprecise because of a selection bias. The purpose of this study is to verify which is better for ankle fusion, AAF or OAF. We regrouped the OAF group into two subgroups according to whether the disease condition is similar to AAF group. The goal is to minimize the impact of disease severity, thereby reducing selection bias to some extent. Methods: We retrospectively analyzed the data of ankle fusion in our hospital between July 2015 and October 2018. 43 patients were enrolled and divided into AAF group (n=17) and OAF group (n=26). In order to eliminate selection bias, we divided OAF group into serious condition subgroup (SC subgroup) (n=15) and not serious condition subgroup (NSC subgroup) (n=11). The NSC subgroup condition is similar to AAF group. Then, we compared the differences between these groups. All patients were followed up at least one year after operation. We analyzed data, including etiology composition, surgical time, intra-op blood loss, reduction of albumin, total hospital stays, union time, fusion situation, complications, radiological examination, functional score and questionnaire survey. Then we performed statistical analyses. Results: We found that the etiological components of AAF group and OAF group were different, the etiological components of AAF group and NSC subgroup were similar. We found that AAF group has advantages over OAF group and SC subgroup in general. However, except in terms of surgical trauma, hospital stays and short-term complications occurred, the AAF group has not obvious advantages over NSC subgroup, including intra-op blood loss, fusion condition, postoperative function score and postoperative patient satisfaction; and AAF group need more surgical time than the NSC subgroup. Conclusions: The arthroscopic ankle fusion can bring a good curative effect. However, if the condition is similar, the arthroscopic ankle fusion only has a limited advantage over the open operation in beautiful incision, perioperative soft tissue protection and enhanced recovery after surgery.

Structures are easily corroded in the Salt Lake areas of China, especially in sulfate solution. This study was intended to settle the problem of sulfate corrosion failure of concrete structures, the influences of different contents of super absorbent polymer (abbreviated as SAP) on the working performance, mechanical properties, corrosion resistance and expansion performance of cement mortar were studied. The mechanism of SAP in mortar was analyzed and studied by SEM. The results showed that although SAP could slightly decrease the fluidity and strength of cement mortar, but it could remarkably improve the coefficient of resistance erosion of specimens and the inflation coefficient of cement paste. When the content of SAP was 0.3%, the sulfate corrosion resistance and expansion performance of specimens showed the best (the coefficient of resistance erosion and inflation coefficient of mortar specimens were 0.95 and 0.97, respectively). Besides, SAP could release much water in the hydration process, form irregular holes, and increase the porosity of mortar specimens. There would more hydration products generated and filled in the pores during the hydration process, thereby improving the sulfate resistance of mortar specimens. Therefore, this research provides theoretical guidance and basis for the study of sulfate corrosion damage of concrete structures in the future.

Colloidal quantum dot-polymer hybrid light emitting diodes (QLEDs) that exhibit external quantum efficiencies >12% for all three primary colors (21% from green) have been demonstrated. These high efficiencies result in part from a positive aging effect reported here for the first time, where positive aging means the efficiency of the QLED increased with time. We have achieved 470 h operational life time (T90) at 2550 nits for red QLEDs. At longer times, negative aging phenomena lead to lower luminance and limit the lifetime of the QLEDs. It is concluded that we have reasonable control over the efficiency of QLEDs. The next challenge is to achieve lifetimes sufficiently long for all three primary colors for applications such as in television and illumination.

BackgroundThis study aimed to examine the efficacy and safety of the arthroscopic treatment of osteochondral lesion of talus (OLT) and lateral ankle instability. It was hypothesized that the outcome of all-arthroscopic surgery was no worse than that of the combined open and arthroscopic surgery for treating chronic lateral ankle instability accompanied by OLT.MethodsThe patients diagnosed of chronic lateral ankle instability accompanied by OLT, who were surgically treated between May 2015 and May2017, were targeted for inclusion. Specifically, patients who received the arthroscopic treatment of OLT and lateral ankle instability were enrolled in the all-arthroscopic group, while patients who received the arthroscopic treatment of OLT and open lateral ankle stabilization were enrolled in the combined open and arthroscopic group. All the patients were followed up in terms of the Karlsson Ankle Functional Score, visual analog scale (VAS) score, Tegner activity score, and American Orthopaedic Foot & Ankle Society (AOFAS) score. Meanwhile, the satisfaction and complication rates were evaluated and compared.ResultsThis retrospective study included a total of 67 patients, including 32 patients in the all-arthroscopic group and 35 patients in the combined group. At a minimum of 24-month follow-up, the functional outcomes were significantly improved in both groups in relation to the preoperative condition. However, the two groups did not differ significantly from each other in terms of the Karlsson score (83.1 ± 8.2 vs 81.7 ± 9.1;P= 0.89), the VAS score (1.8 ± 1.6 vs 2.1 ± 1.7;P= 0.73), the Tegner score (5.5 ± 2.3 vs 5.0 ± 2.1;P= 0.72), and the AOFAS score (87.7 ± 7.6 vs 86.9 ± 7.3;P= 0.77). In addition, the satisfaction and complication rates exhibited no significant differences between the two groups.ConclusionIn comparison with the open lateral ankle stabilization and arthroscopic treatment of OLT, the all-arthroscopic procedure showed no difference in clinical outcomes at a minimum of 24-month follow-up. Despite the benefits of minimally invasive arthroscopic procedure combined with a relatively aggressive postoperative rehabilitation protocol, the clinical outcomes for patients with chronic lateral ankle instability accompanied by OLT did not yield significant improvement.Trial registrationThe present study was carried out with the approval issued by the Institutional Review Board of Xiangya Hospital (no. 202002010).

Background aims Osteoporosis (OP) is a common bone metabolic disease with a high incidence. Our study aimed to explore the pseudogene PTENP1/miR-214/PTEN axis to modulate the osteoclast differentiation in osteoporosis. Methods Patients with osteoporosis were recruited in our study, and RANKL-induced osteoclast differentiation and ovariectomy-induced osteoporosis mouse model were established in vitro and in vivo, respectively. Results Pseudogene PTENP1 and PTEN were significantly down-regulated and miR-214 was up-regulated in osteoporosis patients. In addition, overexpression of PTENP1 or silence of miR-214 inhibited the expression levels of osteoclast specific markers and osteoclast differentiation induced by RANKL. Overexpression of PTENP1 or silence of miR-214 also inhibited the levels of phosphorylation of PI3K and AKT, p65 nuclear translocation, IκBα degradation and the expression level of NFATc1. AlsoSilence of PTENP1 or overexpression of miR-214 induced the osteoclast differentiation under normal physiological condition. Pseudogene PTENP1 sponged miR-214 to regulate the expression of PTEN. Conclusions In an ovariectomy-induced osteoporosis mouse model, obvious pathological changes in bone tissues were found, and bone marrow mononuclear cells in this group were more likely to differentiate into osteoclasts. Therefore, pseudogene PTENP1 sponged miR-214 to regulate the expression of PTEN to inhibit osteoclast differentiation and attenuate osteoporosis by suppressing the PI3K/AKT/NF-κB signaling pathway.

Background It is challenging to create an ideal artificial acetabulum during total hip arthroplasty (THA) in adult DDH. Our team developed a new patient-specific instrument (PSI) that uses the superolateral rim of the acetabulum as a positioning mark to assist in the production of an artificial acetabulum in adult Crowe II/III DDH patients. The purpose of this retrospective study is to verify whether this new PSI can be used to implement the preoperative plan accurately and quickly to create an ideal artificial acetabulum during THA in adult Crowe II/III DDH patients. Methods We selected suitable adult Crowe II/III DDH patients from the registration system for artificial joint surgery at our hospital during April 2016 to March 2018 who underwent THA assisted by a PSI using the superolateral rim of the acetabulum as a positioning mark. We retrospectively analyzed data, including preoperative and postoperative anteversion, inclination, postoperative bilateral rotator center discrepancy (BRCD), surgery time, and the incidence of neurovascular injury. All patients underwent follow-up, and their Harris hip score (HHS) and X-ray data were recorded. Then, we performed statistical analyses on the data described above. Results A total of 20 hip surgeries from 17 patients were included in our study. All patients underwent a successful operation assisted by the PSI. The mean anteversion of the cup in our preoperative plan was 15.1° (range, 10.0° to 20.0°), while the mean postoperative anteversion of the cup was 15.3° (range, 7.0° to 28.6°). The mean inclination of the cup in our preoperative plan was 44.7° (range, 40.0° to 50.0°), while the mean postoperative inclination of the cup was 45.6° (range, 35.0° to 57.6°). Paired-samples t test revealed no significant differences in anteversion and inclination between pre- and postoperation times (P > 0.05). The mean BRCD was 3.38 ± 3.0 mm (range, 0.5 to 11.0 mm). The average operation time was 105.1 ± 15.4 min, and no patients had neurovascular injury complications. All patients’ acetabular components appeared clinically and radiologically stable after surgery. The mean HHS values were significantly improved at 12 weeks (P

Background Restoration of the acetabulum during total hip arthroplasty in adults with developmental dysplasia of the hip (DDH-THA) and resumption of hip function remain major challenges. Herein, a new patient-specific instrument (PSI) was developed that uses the superolateral rim of the acetabulum as a positioning marker to assist surgeons in adult DDH-THA. Methods From January 2017 to October 2018, 104 adult DDH patients were randomized to either the PSI group or conventional operation (CO) group, and further divided into eight subgroups by stratified random sampling using Crowe's classification. Complications, Harris hip scores (HHS), and X-ray results were recorded at 3 and 12 months after surgery. Results With the exception of anteversion in CO-Crowe II group patients, there was no difference in the accuracy of cup placement and orientation between the PSI and CO groups in Crowe I and II DDH patients. With the exception of percentage of acetabular cup coverage (PACC) and the qualification rate of Crowe IV PACC patients, among all Crowe III and IV DDH groups, all postoperative indexes of cup orientation and positioning exhibited significant differences between the PSI and CO groups; however, no significant differences were observed in Crowe I and II DDH patients. Conclusions Compared with conventional methods, the new PSI-assisted surgical method improved the accuracy of placement and orientation of the acetabulum and cup prosthesis, optimized the surgical process, reduced complications, and contributed to quicker recovery of hip function after surgery in adults with Crowe III and IV DDH-THA, but little difference was noted for those with Crowe I and II DDH.

Methylammonium lead halide perovskites have been developed as highly promising materials to fabricate efficient solar cells in the past few years. We have investigated degradation of co-evaporated CH3NH3PbI3 films in ambient air, oxygen and water respectively using x-ray photoelectron spectroscopy (XPS), small angle x-ray diffraction (XRD), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The CH3NH3PbI3 film has an excellent atomic ratio and crystallinity. XPS results indicate that the film is not sensitive to oxygen and dry air, while ambient and water exposures achieve similar effects. XRD further indicates a structural conversion to PbI2 and a drastic morphology change from smooth to rough is revealed by AFM and SEM. The experiment indicated that H2O plays a dominated role in the degradation of CH3NH3PbI3 films. The degradation can be characterized by almost complete removal of N, substantial reduction of I, residual of PbI2, C, O, and I compounds on the surface.

Colloidal quantum-dot hybrid light-emitting diodes (QLEDs) have been demonstrated that exhibit external quantum efficiencies >12% for all three colors (21% from green), both positive and negative ageing, and good charge injection. The role of nanoparticles in QLED charge injection was illustrated.

Background Osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is of much significance for bone formation, the imbalance of it would result in osteoporosis and other pathological bone defects. Increasing evidences showed that long non-coding RNAs (lncRNAs) and miRNAs played vital roles in the regulation of osteogenic differentiation. LncRNA KCNQ1OT1 was often regarded as an imprinted lncRNA and was related to tumor progression, while its function in osteogenic differentiation remained unclear. Method qRT-PCR was performed to detect the expression of KCNQ1OT1, miR-214 and osteogenesis-related genes BMP2, Runx2, OPN, and OCN. Western blotting was carried out to detect osteogenesis-related markers. The osteoblastic phenotype was evidenced by alkaline phosphatase (ALP) activity and Alizarin Red S accumulation detection. Bioinformatics and luciferase assays were used to predict and validate the interaction between KCNQ1OT1 and miR-214 as well as BMP2 and miR-214. Results KCNQ1OT1 was significantly up-regulated during the process of osteogenic induction while miR-214 was contrarily down-regulated. Knockdown of KCNQ1OT1 inhibited osteogenic differentiation and down-regulated BMP2 and osteogenesis-related genes. It was also confirmed that KCNQ1OT1 directly interacted with miR-214. Meanwhile, miR-214 could bind to 3′UTR of BMP2 and therefore inhibited its expression. Furthermore, co-transfection of miR-214 inhibitor could rescue the down-regulation of BMP2 and osteogenesis-related genes and osteogenic differentiation suppression induced by KCNQ1OT1 knockdown. Moreover, miR-214 inhibitor significantly reversed the decreased protein levels of p-Smad1/5/8, Runx2 and Osterix induced by shKCNQ1OT1. Conclusions KCNQ1OT1 positively regulated osteogenic differentiation of BMSCs by acting as a ceRNA to regulate BMP2 expression through sponging miR-214.

Can Xu, Mingqing Li, Chenggong Wang, Hui Li, Hua Liu Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, People’s Republic of China Purpose: Hallux valgus surgery often results in significant postoperative pain. Adequate control of pain is essential for patient satisfaction and improves the outcome of the procedure. This study aimed to investigate the perioperative analgesic effect of a buprenorphine transdermal patch in patients who underwent hallux valgus surgery.Patients and methods: A total of 90 patients were randomly divided into the following three groups based on the perioperative analgesic method: flurbiprofen axetil intravenous injection (Group F), oral celecoxib (Group C), and buprenorphine transdermal delivery system (BTDS) (Group BTDS). The pain status, degree of satisfaction, adverse effects, and administration of tramadol hydrochloride for uncontrolled pain were recorded on the night before surgery, postoperative day 1, postoperative day 2, and postoperative day 3.Results: The BTDS could effectively control perioperative pain for patients undergoing ­hallux valgus surgery. The analgesic effect of the BTDS was better than that of oral celecoxib. In addition, statistically significant differences were not observed in the visual analog scale (VAS) scores, adverse effects, and rescue analgesia between the patients who received the BTDS and the patients who received the flurbiprofen axetil intravenous injection. However, the degree of patient satisfaction of the BTDS group was significantly higher (P

Degradation of coevaporated CH3NH3PbI3 thin films were investigated with X-ray photoelectron spectroscopy and X-ray diffraction as the films were subjected to exposure of oxygen, low pressure atmospheric air, atmospheric air, or H2O. The coevaporated thin films have consistent stoichiometry and crystallinity suitable for detailed surface analysis. The results indicate that CH3NH3PbI3 is not sensitive to oxygen. Even after 1013 Langmuir (L, one L equals 10–6 Torr s) oxygen exposure, no O atoms could be found on the surface. The film is not sensitive to dry air as well. A reaction threshold of about 2 × 1010 L is found for H2O exposure, below which no CH3NH3PbI3 degradation takes place, and the H2O acts as an n-dopant. Above the threshold, the film begins to decompose, and the amount of N and I decrease quickly, leaving the surface with PbI2, hydrocarbon complex, and O contamination.

The vacuum propagation of a laser beam is strictly solved on the basis of (1) the wave equation, (2) Gauss’s law, (3) finite power, and (4) a group velocity equal to c. The direct vacuum acceleration of the classic charge is then studied based on the strictly solved vacuum laser field. Different vacuum states of the laser beam are chosen by the physical nature of the interface between the vacuum and the solid optical material.

It is demonstrated that hydroxyapatite, a type of calcium phosphate commonly found in bone tissue, retains surprisingly large stored charge when synthesized electrochemically from aqueous solution. Thin films of hydroxyapatite formed on titanium and stainless steel electrodes were found to display giant polarization with quasi-permanent stored charge in excess of 70 000 microcoulombs per square centimeter. The polarization of the hydroxyapatite film develops during synthesis as a result of field-induced changes in concentration of ionic reactants in the electrical double layer near the electrode surface. This novel mechanism of polarization during synthesis provides much larger stored charge than what is possible by postsynthesis poling of ferroelectric or electret materials. The polarized hydroxyapatite films on titanium are shown through in vitro experiments to hold promise in stimulating bone growth and may enable new applications in ion exchange separations, drug delivery, or energy storage.

Interfacial electronic structures of MoO3 and LiF-modified pentacene (PEN)/fullerene (C60)-based charge generation layer (CGL) have been investigated with photoemission spectroscopy. Important characteristics controlling its functional effectiveness have been analyzed for charge transport properties in tandem organic lighting-emitting diodes (TOLEDs). It is found that a small energy offset at the PEN/C60 heterojunction makes it easy to transfer electrons from PEN to C60 even under a small applied bias, facilitating the occurrence of charge generation. The band bending observed in both PEN and C60 is beneficial to exciton-dissociation and charge transport in opposite directions. At the MoO3/PEN interface, the high work function (WF) of MoO3 brings the highest occupied molecular orbital (HOMO) onset up to the Fermi level (EF) not only for PEN but also for most hole transport layer (HTL) materials of the adjacent electroluminescent (EL) unit as this CGL is connected into TOLED. Therefore, holes can be efficiently injected from PEN into this EL unit. Similarly, at the C60/LiF interface, the low WF of the LiF buffer layer makes the lowest unoccupied molecular orbital (LUMO) to pin close to the EF not only for C60 but also for most electron transport layer (ETL) materials of the other EL unit, which induces the electrons to inject easily from C60 into that EL unit by tunneling through the thin LiF film. The favorable energy level alignment can effectively enhance charge generation, transport, and injection. The advantage of the MoO3/PEN/C60/LiF structure is that thus formed CGL can greatly reduce the voltage drop and thus enhance the power efficiency (PE) of the corresponding TOLED.

The electronic properties of interfaces formed between Au and organometal triiodide perovskite (CH3NH3PbI3) are investigated using ultraviolet photoemission spectroscopy (UPS), inverse photoemission spectroscopy (IPES) and X-ray photoemission spectroscopy (XPS). It is found that the CH3NH3PbI3 film coated onto the substrate of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS)/indium tin oxide (ITO) by a two-step method presents n-type semiconductor behavior, with a band gap of 1.7 eV and a valence band (VB) edge of 1.0 eV below the Fermi energy (EF). An interface dipole of 0.1 eV is observed at the CH3NH3PbI3/Au interface. The energy levels of CH3NH3PbI3 shift upward by ca. 0.4 eV with an Au coverage of 64 Å upon it, resulting in band bending, hence a built-in field in CH3NH3PbI3 that encourages hole transport to the interface. Hole accumulation occurs in the vicinity of the interface, facilitating the hole transfer from CH3NH3PbI3 to Au. Furthermore, the shift of the VB maximum of CH3NH3PbI3 toward the EF indicates a decrease of energy loss as holes transfer from CH3NH3PbI3 to Au.

Ankylosing spondylitis is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the spine and the sacroiliac joints. To date, the disease etiology remains unclear. In the present study, the correlation of T lymphocyte subset changes with the progression of ankylosing spondylitis was investigated. A total of 55 patients with ankylosing spondylitis (22 severe and 23 mild cases) and 20 healthy individuals were selected. Firstly, the punctured cells in the lesions and the serum were collected, and the lymphocytes and the peripheral blood mononuclear cells were prepared. Secondly, quantitative PCR, ELISA and flow cytometry analyses were carried out to detect the levels of a series of immunoglobulins, complements, helper T cells, cytotoxic T cells, regulatory cells and cytokines. The expression levels of α-globulin, γ-globulin, immunoglobulin (Ig)G, IgA, IgM, serum complement C3, and complement C4 were found to be significantly increased in ankylosing spondylitis patients. In addition, the percentage of Th1 and Th17 cells was found to be significantly higher in the ankylosing spondylitis groups (mild and severe) compared with the healthy individuals. As a result, the Th1/Th2 and Th17/Treg ratios were significantly higher in patients with ankylosing spondylitis. In addition, T lymphocyte subset ratio imbalances contributed to an increased expression of immune mediators, including interferon (IFN)-γ and interleukin (IL)-17A. The mRNA and protein expression levels of IFN-γ and IL-17A were found to be higher in the ankylosing spondylitis groups compared with the control group. The present study provided further evidence on the function and underlying mechanism of T lymphocyte subsets, which may be useful in the diagnosis and treatment of ankylosing spondylitis.

Organolead trihalide perovskites are emerging excellent active materials for thin film solar cells. Here, the formation and evolution of methylammonium lead iodide perovskite thin films grown by the low-temperature thermal annealing induced interdiffusion process are investigated. It is found that thermal annealing not only drives the formation of perovskite but also affects the morphology, optoelectronic properties and correlated device performance. Thermal annealing at 105 °C quickly drives the formation of phase-pure perovskite in a short time of 15 min, and continued thermal annealing up to two hours continuously increases the perovskite crystallinity and grain size without losing film continuity or coverage. The measured Hall mobility increases monotonically to 36.0 cm2 V−1 s−1 upon annealing, which is correlated with the increased crystallinity and grain size. Device efficiencies increase with an increased short circuit current density and fill factor with a longer annealing time up to two hours, and the highest device efficiency of 13.4% is achieved. It is found that the reduction of work function in the perovskite films, caused by the increased annealing duration, is linearly correlated with the open circuit voltage loss, which points out a path for the further increase of the device efficiency.

A buffer layer based on a Te/Cu bi-layer useful for forming ohmic contact to p-CdTe has been developed for application in CdS/CdTe solar cells. The bi-layer buffer was prepared by vapor deposition and a thermal annealing (~200 °C) was required for activation. Enhanced efficiency and stability were obtained by optimizing the Cu/Te compositions and the thermal activation conditions. Characterization by XRD, XPS, and PL indicates that under the thermal activation conditions Cu diffuses rapidly in the Te without forming CuxTe compounds. The enhanced stability can be attributed to the mediation of Cu diffusion into CdTe by the Te layer. The Te/Cu buffers are particularly useful for the fabrication of ultra-thin CdS/CdTe solar cells.

β-tricalcium phosphate (β-TCP) and platelet-rich plasma (PRP) are commonly used in bone tissue engineering. In the present study, a new composite combining strengthened β-TCP and PRP was prepared and its morphological and mechanical properties were investigated by scanning electron microscopy (SEM) and material testing. The biocompatibility was evaluated by measuring the adhesion rate and cytotoxicity of bone marrow stromal cells (BMSCs). The strengthened β-TCP/PRP composite had an appearance like the fungus Boletus kermesinus with the PRP gel distributed on the surface of the micropores. The maximum load and load intensity were 945.6±86.4 N and 13.1±0.5 MPa, which were significantly higher than those of β-TCP (110.1±14.3 N and 1.6±0.2 MPa; P96% after 24 h, with a cell cytotoxicity value of zero. SEM micrographs revealed that following seeding of BMSCs onto the composite in high-glucose Dulbecco’s modified Eagle’s medium culture for two weeks, the cells grew well and exhibited fusiform, spherical and polygonal morphologies, as well as pseudopodial connections. The strengthened β-TCP/PRP composite has the potential to be used as a scaffold in bone tissue engineering due to its effective biocompatibility and mechanical properties.