Recycling and high-value utilization of polyethylene terephthalate wastes: A review.

Polyethelene terephthalate (PET) is a well-known thermoplastic, and recycling PET waste is important for the natural environment and human health. This study provides a comprehensive overview of the recycling and reuse of PET waste through energy recovery and physical, chemical, and biological recycling. This article summarizes the recycling methods and the high-value products derived from PET waste, specifically detailing the research progress on regenerated PET prepared by the mechanical recycling of fiber/yarn, fabric, and composite materials, and introduces the application of PET nanofibers recycled by physical dissolution and electrospinning in fields such as filtration, adsorption, electronics, and antibacterial materials. This article explains the energy recovery of PET through thermal decomposition and comprehensively discusses various chemical recycling methods, including the reaction mechanisms, catalysts, conversion efficiencies, and reaction products, with a brief introduction to PET biodegradation using hydrolytic enzymes provided. The analysis and comparison of various recycling methods indicated that the mechanical recycling method yielded PET products with a wide range of applications in composite materials. Electrospinning is a highly promising recycling strategy for fabricating recycled PET nanofibers. Compared to other methods, physical recycling has advantages such as low cost, low energy consumption, high value, simple processing, and environmental friendliness, making it the preferred choice for the recycling and high-value utilization of waste PET.

The Application of Sesamoid Position in Diagnosing Thumb Metacarpophalangeal Joint Dorsal Dislocation: A Retrospective Study.

OBJECTIVES: The position of sesamoid of thumb metacarpophalangeal (MCP) joint changed clearly when the joint was dislocated dorsally. However, the significance of sesamoid location in diagnosing joint dislocation was unclear. The present study aimed to explore the positional relationship between sesamoid bone and thumb metacarpophalangeal joint in normal and dorsal dislocation joints. METHODS: Between January 2018 and August 2023, we collected 60 isometric plain films from sixty outpatients and reviewed 56 anisometric plain films from twenty-eight emergency patients with dorsal dislocation of thumb MCP joint at Tianjin Hospital, then took measurements on the hand X-ray images. The sesamoid length on its longitudinal axis was defined as DP, the distance between the distal edge of sesamoid and thumb MCP joint was defined as DJ, and the ratio of DJ and DP was R. An independent-samples t-test and paired-samples t-test was utilized to analyze difference among data groups. RESULTS: The 60 isometric images were from 30 male and 30 female outpatients with normal bone structure in their hands, and the 56 anisometric images of the 28 emergency patients included both preoperative and postoperative materials. Among the outpatients, the actual distance between the distal edge of sesamoid and thumb MCP joint space (DJ) was 2.09 mm and 1.40 mm in males and females, respectively. The authentic average length of sesamoid (DP) was 4.46 mm in males and 4.22 mm in females. The average value of R (the ratio of DJ and DP) in males and females was 0.49 and 0.34, respectively. There were gender-related statistical differences in DJ (p < 0.01) and R (p=0.01), but no statistical difference in DP (p > 0.05). For the 28 emergency patients, the mean value of R was -0.47 before joint reduction and 0.58 after joint reduction, with statistical difference between them (p < 0.01). CONCLUSIONS: There was significant difference in the relative position between sesamoid and thumb MCP joint when joint dislocation and joint reduction. The distal edge of sesamoid beyond thumb MCP joint could be an evidence in diagnosing joint dorsal dislocation. The distal edge of sesamoid below thumb MCP joint could be an evidence of joint reduction.

Application of WALANT technique for repairing finger skin defect with a random skin flap.

BACKGROUND: Wide-awake local anesthesia no tourniquet (WALANT) technique has emerged among hand surgeons with other indications. Surgeries involving pedicled flap and revascularization are no longer used as contraindications. The present study aimed to evaluate the feasibility and merits of the WALANT technique in random skin flap surgery. METHODS: From May 2018 to March 2019, 12 patients with finger skin defects repaired with random skin flaps were reviewed. Abdominal skin flaps or thoracic skin flaps were used to cover the wound. Both the fingers and the donor sites were anesthetized by the WALANT technique. A 40-mL conventional volume consisted of a mixture of epinephrine and lidocaine. A volume of 5 mL was injected at the distal palmar for nerve block, the other 5 mL was injected around the wound for hemostasis, and the remaining was injected at the donor site of flaps for both analgesia and hemostasis. Baseline data with respect to sex, age, side, type of finger, donor sites, flap size, dosage of anesthetics, usage of finger tourniquet, intraoperative and postoperative pain, hemostasis effect, operation time, Disabilities of the Arm, Shoulder, and Hand Questionnaire (QuickDASH) score, and hospitalization expense, were collected. RESULTS: All patients tolerated the procedure, and none of them needed sedation. Single finger skin defect in 8 patients and double finger skin defect occurred in 4 patients; 5 patients were repaired by abdominal skin flaps, and 7 patients were repaired by thoracic skin flaps. The good surgical field visibility was 91.7%. All flaps survived adequately, without necrosis, pulling fingers out, and other complications. The average visual analog scale (VAS) score of the maximal pain was 1.1 in fingers vs. 2.1 in donor sites during the operation. On postoperative day one, the average VAS score of the maximal pain in fingers and donor sites was 1.3 and 1.1, respectively. The average hospitalization expense before reimbursement of the whole treatment was 11% less expensive compared to the traditional method. The average QuickDASH score was 9.1. CONCLUSIONS: Under wide-awake anesthesia, patients have the ability to control their injured upper extremities consciously, avoiding the complications due to pulling flap pedicles. With the merits of safety, painlessness, less bleeding, and effectivity, the WALANT technique in random skin flaps is feasible and a reliable alternative to deal with finger skin defect.

Development and Validation of Prognostic Nomogram in Patients With WHO Grade III Meningioma: A Retrospective Cohort Study Based on SEER Database.

INTRODUCTION: World Health Organization (WHO) Grade III meningioma is a central nervous system tumor with a poor prognosis. In this retrospective cohort study, the authors constructed a nomogram for predicting the prognosis of WHO Grade III meningioma. METHODS: The patients of this nomogram were based on the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2018. All patients were randomly divided into a development cohort (964 patients) and a validation cohort (410 patients) in a 7:3 ratio. The least absolute shrinkage and selection operator (LASSO) regression was used to screen the predictors. The Cox hazards regression model was constructed and the prognosis was visualized by nomogram. The performance of the prognostic nomogram was determined by consistency index (C-index), clinical net benefit, and calibration. RESULTS: Eight variables were included in the nomogram: gender, race, age at diagnosis, histology, tumor site, tumor size, laterality, and surgical method. The C-index of the training set and verification set were 0.654 and 0.628. The calibration plots showed that the nomogram was in good agreement with the actual observation. The clinical decision curve indicates that the nomogram has a good clinical net benefit in WHO Grade III meningioma. CONCLUSIONS: A prognostic nomogram of a large cohort of WHO Grade III meningioma was established and verified based on the SEER database. The nomogram we established may help clinicians provide personalized treatment services and clinical decisions for patients.

Development and validation of prognostic nomogram in ependymoma: A retrospective analysis of the SEER database.

BACKGROUND: The prognostic factors for survival in patients with ependymoma (EPN) remain controversial. The aim of this study was to establish a prognostic model for 5- and 10-year survival probability nomograms for patients with EPN. METHODS: Clinical data from the Surveillance, Epidemiology, and End Results (SEER) database were used for patients diagnosed with ependymoma between 2000 and 2018 and were randomized 7:3 into a development set and a validation set. Factors significantly associated with prognosis were screened out using the least absolute shrinkage and selection operator (LASSO) regression. The calibration chart and consistency index (C-index) are used to evaluate the discrimination and consistency of the prediction model. Decision curve analysis (DCA) was used to further evaluate the established model. Finally, prognostic factors selected by LASSO regression were evaluated using Kaplan-Meier (KM) survival curves. RESULTS: A total of 3820 patients were included in the prognostic model. Seven survival predictors were obtained by LASSO regression screening, including age, gender, morphology, location, size, laterality, and resection. The prognostic model of the nomogram showed moderate discriminative ability in the development group and the validation group, with a C-index of 0.642 and 0.615, respectively. In the development set and validation set survival curves, the prognosis index of high risk was less effective than low risk (p < 0.001). CONCLUSIONS: Our nomograms may play an important role in predicting 5 and 10-year outcomes for patients with ependymoma. This will help assist clinicians in personalized medicine.

Synthesis and Study of Zinc Orotate and Its Synergistic Effect with Commercial Stabilizers for Stabilizing Poly(Vinyl Chloride).

Zinc orotate (ZnOr2), which is a new kind of poly(vinyl chloride) (PVC) stabilizer, is prepared in this work through the precipitation method, and its impact on the thermal stability of PVC is measured by thermogravimetric analysis (TG), Congo red test, and discoloration test. The results exhibit that the thermal stability of PVC is positively enhanced after the addition of ZnOr2. In contrast with a commercial thermal stabilizer, zinc stearate (ZnSt2), a noteworthy improvement was observed that ZnOr2 could postpone the "zinc burning" of PVC. This is principally ascribed to the Or anion in the structure of ZnOr2 being able to absorb the HCl released by PVC, and to supersede unstable chlorine atoms in the structure of PVC. In addition, blending ZnOr2 with calcium stearate (CaSt2) in diverse mass ratios can significantly accelerate the thermal stability of PVC. Optimum performance was achieved with a CaSt2:ZnOr2 ratio of 1.8:1.2. Moreover, an outstanding synergistic effect can be observed when CaSt2/ZnOr2 is coupled with other commercial auxiliary stabilizers. The initial color and long-term stability of PVC including CaSt2/ZnOr2 is significantly increased when pentaerythritol (PER) is added, while dibenzoylmethane (DBM) can only improve its long-term thermal stability.

[Evaluation of reconstruction of extensor pollicis function by transfer of extensor indicis].

OBJECTIVE: To assess the long-time results of reconstruction of the extensor pollicis longus (EPL) function by transfer of the extensor indicis (EI). METHODS: From August 1978 to March 2003, 46 cases of loss of the EPL function were treated by transfer of the extensor indicis. Of 46 cases, there were 32 males and 14 females, aged 16-51 years with an average of 36 years; there were 24 cases of old traumatic rupture and 22 cases of secondary rupture. The disease course was 2 days to 5 months, averaged 74 days. A specific EI-EPL evaluation method (SEEM) was used to measure the EPL function after transfer. RESULTS: Forty-one cases were followed up 9 years and 3 months on average (7 months to 23 years). Based on the SEEM, the results were excellent and good in 39 of 41 patients. The elevation deficit and combined flexion deficit were 0-2.2 cm (1.8 cm on average) and 0-3 cm (1.6 cm on average); the independent extension deficit was 0 degrees-8 degrees (5 degrees on average). CONCLUSION: Restoration of the extensor pollicis function by transfer of the extensor indicis is an effective and safe treatment option and the SEEM is a valid method for assessing EPL function.

[Treatment of old scaphoid fracture with Russe technique].

OBJECTIVE: To report the effect of Russe technique in treating old scaphoid fracture. METHODS: From January 1987 to February 1999, 11 cases of old scaphoid fractures were treated with Russe technique. The follow-up period averaged 5 years and 7 months. RESULTS: The fracture healing rate was 100%, and wrist pain was completely relieved in all cases. The ranges of motion averaged 41.2 degrees of flexion, 40.5 degrees of extension, 8.7 degrees of radial deviation, and 15.4 degrees of ulnar deviation. The grip strength reached 82.9% of the normal side. CONCLUSION: Russe technique is an effective and safe method of treatment for old scaphoid fracture.