Prediction Models of Mechanical Properties of Jute/PLA Composite Based on X-ray Computed Tomography.

The tensile strength and modulus of elasticity of a jute/polylactic acid (PLA) composite were found to vary nonlinearly with the loading angle of the specimen through the tensile test. The variation in these properties was related to the fiber orientation distribution (FOD) and fiber length distribution (FLD). In order to study the effects of the FOD and FLD of short fibers on the mechanical properties and to better predict the mechanical properties of short-fiber composites, the true distribution of short fibers in the composite was accurately obtained using X-ray computed tomography (XCT), in which about 70% of the jute fibers were less than 300 µm in length and the fibers were mainly distributed along the direction of mold flow. The probability density functions of the FOD and FLD were obtained by further analyzing the XCT data. Strength and elastic modulus prediction models applicable to short-fiber-reinforced polymer (SFRP) composites were created by modifying the laminate theory and the rule of mixtures using the probability density functions of the FOD and FLD. The experimental measurements were in good agreement with the model predictions.

Breast-conserving surgery is associated with a lower incidence of suicide among females with breast cancer in the United States: a population-based retrospective cohort study.

BACKGROUND: With comparable overall survival and local recurrence rates with mastectomy, breast-conserving surgery (BCS) has become the cornerstone of therapy for breast cancer; however, the difference in the incidence of suicide between BCS and mastectomy among breast cancer survivors remains unclear. This study evaluated the mortality risk from suicide among breast cancer survivors and compared suicide risk between BCS and mastectomy using a population-based cohort. MATERIALS AND METHODS: Female patients newly diagnosed with first primary breast cancer, recorded in the Surveillance, Epidemiology and End Results database, were included. Standardized mortality ratio (SMR) and cumulative mortality rate from suicide among those who underwent BCS and mastectomy were compared. RESULTS: A total of 1 190 991 patients with newly diagnosed first primary breast cancer were included in the study, of whom 56.5% underwent BCS and 36.1% underwent mastectomy. During the follow-up period, 667 suicides were recorded. Patients who underwent mastectomy exhibited significantly higher suicide mortality than the general population [mortality rate, 8.16 per 100 000 person-years; SMR 1.18 (95% CI 1.05-1.33)], while there was no significant difference in suicide rate between patients who underwent BCS and the general population [SMR 0.92 (95% CI 0.83-1.02)]. Multivariate Cox analysis revealed that BCS, compared with mastectomy, was associated with a significantly decreased risk of suicide among females with breast cancer [hazard ratio 0.80 (95% CI 0.68-0.95); P = 0.009]. CONCLUSION: BCS was associated with a significantly lower incidence of suicide among females with breast cancer. BCS offers a compelling option for improving the quality of life and self-esteem of patients with cancer and provides a novel perspective on cancer management.

Endoscopic excision versus radical nephroureterectomy for non-muscle invasive upper tract urothelial carcinoma: A population-based large cohort study.

Background: As an important kidney-sparing treatment for upper urothelial carcinoma (UTUC), whether endoscopic excision can be performed without sacrificing oncologic outcomes remains indefinite. This study aimed to investigate the prevalence and efficacy of endoscopic excision, in patients with non-muscle invasive UTUC (NMIUTUC) and compare them to those of radical nephroureterectomy (RNU). Methods: Using the Surveillance, Epidemiology, and End Results database, we reviewed 4347 cases with NMIUTUC (cTis/Ta/T1-N0-M0,≤ 5.0 cm) between 2004 and 2020. Surgical treatment modalities included endoscopic excision and RNU. Propensity score matching analysis was used to minimize the selection bias between endoscopic excision and RNU, selecting 1:1 matched patients in the two group. Results: A total of 794 patients with NMIUTUC were included after matching (397:397). Patients who underwent endoscopic excision had worse survival outcomes compared with those of patients who underwent RNU (5-year OS: 65.3 % vs. 80.3 %, p < 0.0001; 5-year DSS: 83.2 % vs. 94.0 %, p = 0.00021). After stratification by anatomical sites, the effect of endoscopic excision for NMI renal pelvis cancer was worse than RNU (5-year OS, 62.9 % vs. 82.8 %; 5-year DSS, 78.8 % vs. 91.6 %), while in NMI ureteral cancer, there is no statistically significant difference in OS and DSS between endoscopic excision and RNU. Further stratification according to tumor grade revealed equivalent tumor control effects of endoscopic excision and RNU in low-grade NMI ureteral cancer (5-year OS: 67.7 % vs. 72.5 %, p = 0.23; 5-year DSS: 87.2 % vs. 93.1 %, p = 0.17); while for renal pelvis tumor and high-grade ureteral tumor, endoscopic excision was related with significantly inferior prognosis. Conclusions: Only for low-grade NMI ureteral cancer, endoscopic excision and RNU are oncologically equivalent, indicating that endoscopic excision might be an effective option for low-grade NMI ureteral cancer. This result needs to be further verified in randomized controlled trials.