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Background and purpose: The standard therapy for locally advanced rectal cancer (LARC) is neoadjuvant chemoradiotherapy (nCRT) followed by surgery. NCRT can make the tumor regress and downstage, and increase the R0 resection rate. However, individual differences in rectal cancer are large, and some patients respond poorly to nCRT and cannot benefit from nCRT. Therefore, it is necessary to establish effective screening measures to identify patients with poor response to nCRT. This study aimed to analyze the influencing factors of nCRT for LARC and construct the tumor regression prediction model. Methods: Data of 158 LARC patients who underwent total mesenteric resection after receiving nCRT at the First Hospital Affiliated to Air Force Medical University from January 2016 to December 2020 were collected. Baseline clinical indicators before nCRT were collected, including laboratory examination, tumor markers and magnetic resonance imaging (MRI). According to the tumor size reported by MRI before and after nCRT, Response Evaluation Criteria in Solid Tumors (RECIST) was used to evaluate the extent of tumor regression after nCRT. After receiver operating characteristic (ROC) curve was used to standardize the clinical baseline indicators, logistic regression analysis was carried out to screen the factors affecting the tumor regression. The tumor regression prediction model was constructed by logistic regression, and the performance of the model was evaluated based on decision curve analysis (DCA) and the calibration curve. The accuracy of the model was tested by 10-fold cross-validation. Results: This retrospective cohort study enrolled 158 patients, in which, 98 patients achieved complete response (CR) or partial response (PR). The objective response rate was 62%. Sixty patients had poor response to nCRT, either stable disease (SD) or progressive disease (PD). Multivariate logistic regression analysis showed that tumor diameter before treatment (P

The effects of 200 keV and 10 MeV electron-irradiation accelerators on the eradication of lasioderma serricorne and bacteria in tobacco and on the quality of tobacco leaf are investigated. By controlling the parameters of electron-beam irradiation, all lasioderma serricorne and bacteria inside tobacco can be eradicated efficiently and rapidly. The irradiated tobacco exhibits good retention based on a validation experiment, and no colonies are detected within 38 d. The irradiation has no significant effects on the basic physical and chemical indexes or the organic-acid and mineral-element contents of tobacco. Excessive energy levels reduce the volatilization loss of neophytadiene in tobacco from 589.91 to 418.64 μg/g, which indicates that the aroma quality of the tobacco deteriorates to a certain extent. Fluka simulation results show that a 3 MeV electron beam is sufficient to penetrate a full box of stored tobacco at existing tobacco stacking densities.

In this investigation, we employed the anharmonic phonon renormalization method to analyze the thermal conductivity of two-dimensional (2D) carbon materials, while also examining the influence of quartic (fourth-order) scattering on heat transport within this class of materials. Our study centered on a representative silicon–carbon (Si–C) 2D system, Si4C8. Notably, conventional Boltzmann transport equation (BTE) calculations with harmonic phonons are inadequate for estimating the thermal conductivity of these materials due to the emergence of imaginary frequencies. Consequently, to elucidate the primary contributors to its heat transport, we employed an integrated yet novel computational framework rooted in a first-principles methodology. This approach combines self-consistent phonon (SCP) theory and the BTE to scrutinize the thermal conduction behavior; the BTE is resolved in conjunction with SCP theory to comprehensively address the quartic anharmonic effects, encompassing both four-phonon (4ph) scatterings and the temperature-induced shift of phonon frequencies. Based on the calculation results, it is evident that the meticulous incorporation of anharmonicity renormalization is pivotal for precise evaluation of the thermal conductivity of 2D Si4C8 and establishing coherent temperature dependency. Through this comprehensive examination, we aim to establish a systematic methodology for investigating the thermal transport mechanisms of 2D Si–C phases with similar bonding networks, offering insights into the intricate relationships between their structural, mechanical, electronic, and thermal properties. [ABSTRACT FROM AUTHOR]