Geothermal power generation and positive impact in the greater bay area: a case study of Huizhou City, Guangdong Province.

Geothermal resources, as abundant renewable and clean natural resources on Earth, have been utilized for geothermal power generation in 29 countries. Guangdong Province, as one of the most developed, economically vibrant, and attractive investment regions in China, has experienced rapid economic growth. However, further development is constrained by resource limitations and severe ecological environmental pressures. The issue of energy consumption and economic growth imbalance needs to be urgently addressed. Geothermal energy, as a clean and stable form of energy, can reduce reliance on fossil fuels, decrease dependence on imported energy, and enhance national energy security. In this study, geological survey, geophysical survey, geochemical survey, remote sensing detection and drilling were carried out in the Shiba-Huangshadong area of Huizhou, and by analyzing the data on geothermal energy reserves in the study area, the available geothermal energy and its potentials in the study area were identified and its impact on the current energy consumption in Huizhou City was assessed, to validate the feasibility of the detailed application of the geothermal energy in the Greater Bay Area, which will enable the energy structure of Huizhou City optimize the energy structure.

Human Mesenchymal Stem Cells-Derived Exosome Mimetic Vesicles Regulation of the MAPK Pathway and ROS Levels Inhibits Glucocorticoid-Induced Apoptosis in Osteoblasts.

Background: Long-term extensive use of glucocorticoids will lead to hormonal necrosis of the femoral head, and osteoblasts play an important role in the prevention of osteonecrosis. However, there is no complete cure for necrosis of the femoral head. Mesenchymal stem cell- (MSCs-) derived exosomes are widely used for the repair of various tissue lesions. Therefore, the aim of this study was to investigate the mechanism of dexamethasone- (DEX-) induced osteoblast apoptosis and the therapeutic effect of human umbilical cord MSC- (hucMSC-) derived exosome mimetic vesicles (EMVs) on osteoblast-induced apoptosis by DEX. Methods: The viability and apoptosis of primary MC3T3-E1 cells were determined by the Cell Counting Kit-8 (CCK-8), FITC-Annexin V/PI staining and immunoblot. The intracellular levels of reactive oxygen species (ROS) after DEX treatment were measured by 2', 7' -dichlorodihydrofluorescein diacetate (DCFH-DA) staining. In this study, hucMSC-EMVs and N-acetyl-l-cysteine (NAC) were used as therapeutic measures. The expression of B-cell lymphoma 2-associated X, Bcl 2, HO-1, and nuclear factor erythroid-derived 2-like 2 and MAPK- signaling pathway in osteogenic cell MC3T3-E1 cells treated with Dex was analyzed by the immunoblotting. Results: DEX significantly induced osteoblasts MC3T3-E1 apoptosis and ROS accumulation. MAPK-signaling pathway was activated in MC3T3-E1 after DEX treatment. hucMSC-EMVs intervention significantly downregulated DEX-induced MAPK-signaling pathway activation and ROS accumulation. In addition, hucMSC-EMVs can reduce the apoptosis levels in osteoblast MC3T3-E1 cells induced by DEX. Conclusions: Our study confirmed that hucMSC-EMVs regulates MAPK-signaling pathway and ROS levels to inhibit DEX-induced osteoblast apoptosis.

Novel method for the treatment of congenital pseudarthrosis of the tibia using the gastrocnemius flap: A preliminary study.

Purpose: Congenital pseudarthrosis of the tibia is a rare disease that is particularly difficult to treat; the most difficult complications include nonunion of the tibia, refracture, and failed surgery. This study aimed to evaluate the efficiency of transposing gastrocnemius flaps for the treatment of congenital pseudarthrosis of the tibia. Methods: Nine patients (aged 6.2 ± 3.6 years) diagnosed with congenital pseudarthrosis of the tibia in our hospital between March 2013 and March 2018 were enrolled. The tibial pseudarthrosis and thickened periosteum were completely removed, and intramedullary nails were used to fix the tibia. Bone harvest from the iliac, mixed with allogenic bone, was filled in the gap created by excision of the pseudarthrosis site and the surrounding periosteum; the gastrocnemius flap was then used to wrap the pseudoarthrosis site. The plaster cast was fixed postoperatively. The tibial union was evaluated via radiograph, and the plaster cast was removed after 12-24 weeks. Patients began walking approximately 12-14 weeks postoperatively. Results: Anatomical reduction was achieved in all the patients; the mean bone healing time was 10.1 ± 2.1 months. Bone nonunion was observed in one patient, and no neurovascular injury or wound infection occurred. Limb length discrepancy was in the range 3.2 ± 1.8 cm at 1 year and 4.7 ± 2.7 cm at 2 years after surgery. Two patients underwent replacement of the intramedullary nail, and eight patients exhibited good functional and radiographic outcomes. Conclusion: This preliminary study proved that using the gastrocnemius muscle flap to cover the pseudarthrosis site was an effective method to promote the tibial union and treat congenital pseudarthrosis of the tibia.

Retrospective analysis of traumatic triradiate cartilage injury in children.

BACKGROUND: To summarize and analyze the epidemiological characteristics, treatment and corresponding curative effect of triradiate cartilage injury(TCI) in children after trauma, to provide a theoretical basis for early diagnosis and improvement of treatment. METHODS: The TCI was classified according to Bucholz classification, and the final curative effect was evaluated with Harris Hip Score and imaging examination during follow-up. Finally, a comprehensive analysis was made by reviewing the cases in the literature combined with the patients in our hospital. RESULTS: A total of 15 cases (18 hips) of triradiate cartilage injuries were collected in our hospital. There was 1 hip with type I injury, nine hips with type II injury, two hips with type IV injury, one hip with type V injury and five hips with type VI injury. Among the 12 cases with complete follow-up, the bone bridge was found in or around the triradiate cartilage in 8 cases, early fusion of triradiate cartilage occurred in 5 patients, 3 cases had hip dysplasia, 4 cases had a subluxation of the femoral head, and HHS was excellent in 8 cases and good in 4 cases. CONCLUSION: The early diagnosis of TCI is still a difficult problem. Conservative treatment is often the first choice. The overall prognosis of acetabular fractures involving triradiate cartilage is poor. The formation of the bone bridge in triradiate cartilage usually indicates the possibility of premature closure, which may lead to severe complications of post-traumatic acetabular dysplasia and subluxation of the femoral head.

Comparison of non-surgical and surgical treatment using absorbable screws in anterior-superior iliac spine avulsion fractures with over 1.5cm displacement.

INTRODUCTION: There is some debate over the best treatment for anterior-superior iliac spine (ASIS) avulsion fractures, although non-surgical treatment can achieve the same results as open surgery. HYPOTHESIS: Absorbable screws can be safely used for ASIS avulsion fractures in children and adolescents. AIM OF THE STUDY: Here, we compared patients on whom no surgery was performed with those who underwent open surgery and investigated the feasibility of using absorbable screws as a new fixation material for treating ASIS avulsion fractures in children and adolescents. PATIENTS AND METHODS: We retrospectively analyzed the data of 59 patients diagnosed with ASIS avulsion fractures in our hospital between January 2009 and December 2016. Based on the clinical data, these patients were assigned into group A (non-surgical group) and group B (absorbable screws group). After the inclusion and exclusion criteria were applied, patients' clinical records, including radiographs, were analyzed. All patients were assessed for range of motion (ROM) and by X-ray as they returned to activity. Evaluation of hip function was done by calculating the American Academy of Orthopedic Surgeons (AAOS) lower limb and hip scores. RESULTS: According to AAOS scores, there were significant differences between the two groups at the first and third months postoperatively (p=0.003), but by the sixth and twelfth months, there was no significant difference (p=0.42). Significant differences were also observed between both groups regarding callus growth on radiographs, time to resume sporting activities, and occurrence of complications such as meralgia paresthetica. All complications resolved by 6 months follow-up. CONCLUSION: Our study agrees with previous reports, absorbable screws can be safely used for ASIS avulsion fractures with greater than 1.5cm displacement in children and adolescents. In comparison with non-surgical therapy, our results indicate that absorbable screws are associated with shorter recovery time and lesser early complications. LEVEL OF EVIDENCE: IV, retrospective study with control group.

Internal Fixation With Absorbable Rods for the Treatment of Displaced Radial Neck Fractures in Children.

BACKGROUND: The treatment of radial neck fractures with complete displacement or severe displacement and an angle of >30 degrees is controversial. The currently used methods, including the Metaizeau technique, are associated with drawbacks such as imperfect reduction, epiphyseal damage, and delayed functional recovery. To overcome these drawbacks, we used absorbable rod fixation followed by early functional training for the treatment of displaced radial neck fractures in children. METHODS: In this study, 68 patients (age, 4 to 12 y; average, 8.4 y; average angle, 58 degrees; average displacement, 53%) with radial neck fractures with Salter-Harris grades II to IV underwent lateral elbow open reduction and absorbable rod fixation. At 3 weeks postoperatively, the patients' plaster casts were removed, and functional training was started. RESULTS: Anatomic reduction was achieved in all patients. We followed-up 68 patients for 6 months to 4 years (average, 41 mo). No cases of radial nerve injury, radial bone necrosis, myositis ossificans, and postoperative infection were observed. The functional recovery was "excellent" in 43 patients, "good" in 13 patients, "average" in 12 patients, and "bad" in 0 patients, according to the Morrey evaluation standard. CONCLUSION: Open reduction with absorbable rod fixation for the treatment of displaced radial neck fractures in children was feasible and was a choice in children. LEVEL OF EVIDENCE: Therapeutic II.

[Soft tissue reconstruction for secondary deformity after correction of Wassel type IV-D thumb duplication].

OBJECTIVE: To investigate an effective therapeutic method for the secondary deformity after the correction of the Wassel type IV thumb duplication. METHODS: 9 cases of Wassel W-D Complex thumb deformities in children with postoperative secondary deformity, including 6 males and 3 female, were treated. The age ranged from 2.0 to 14 years old with an average of 5.3 years old. During the operation, the anatomical structure was dissected to observe the structure and alignment of the flexor tendon as well as anatomical structure of the joint. In the meantime, the flexor pollicis longus tendon was shifted, A2 pulley was reconstructed, joint capsule was released and contracted, the end point of thenar was shifted. Kirschner wires fixation were used for about 4-5 weeks, the brace fixation for about 3 months. RESULTS: All the patients had radial side skin contracture of the interphalangeal joint, radial deviation of the thumb tip, radial side contracture and ulnar relaxation of the joint capsule. Flexor hallucis longus tendon was located in front of the radial side of the proximal phalanx, with no wrapped sheath or A2 pulley. Flexor hallucis longus tendon was attached to the thumb tip substrate, of which 1/3 was located in the center and 2/3 in the radial side. The thumb tip rotated about 10 degrees-15 degrees to the radial side. The patients were followed up for 6-38 months, with an average of 24 months. We adopted Tada standard to evaluate the follow-up results as excellent in 7 cases, good in 1 case, poor in 1 case. CONCLUSIONS: Soft tissue reconstruction for the secondary deformity after the correction of the Wassel type IV-D thumb duplication is an effective method. Application of the brace after removal of Kirschner wires has an important role in preventing the secondary deformity.