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The moving deformation of the strata and the redistribution of stope stress after mining show asymmetrical characteristics, which do not conform to the symmetrical structural characteristics of the original rock beam fracture. To further analyze the deformation of rock beams and the asymmetry law of stope pressure distribution after strata caving, the detailed process of instability and deformation of composite rock beams before failure was revealed through similar material simulation, theoretical analysis, and numerical simulation. Through similar simulation experiments, the structural characteristics of strata caving were observed. After excavation, the caving angle near the open-off cut side of the model is greater than that on the stop-mining line side. The maximum bending moment of the rock beam is located at the open-off cut side. The rock beam fracture is located on the partial open-off cut side in the middle of the rock beam. The rock beam on the open-off cut side is easy to shear slip and not easy to hinge. The rock beam in front of the advancing direction of the working face is easily hinged. Based on the structural characteristics of strata caving, considering the thickness of the composite rock beam, the two-hinged arch mechanical model for rock beam fracture is established. On this basis, the key parameters of rock beam instability and fracture such as limit load, additional horizontal stress, limit break distance, and break position are analyzed. Based on the deformation characteristics of two hinged arches, the caving structure and the asymmetric distribution mechanism of stress redistribution during the deformation of overburden in stope are explained. Finally, the deformation of rock beam and the asymmetry of stress distribution in stope are verified by numerical calculation. The results show that the concentrated stress value of the coal pillar at the open-off cut side is greater than that in front of the working face. There is a pressure relief area behind the working face, and the pressure relief area has a certain range. The range of stress concentration area, pressure relief area, and stress value tend to be stable, and only the range of the original rock stress zone expands when the working face is advanced to a certain distance. The asymmetric distribution of compaction stress in goaf is related to the buckling deformation of strata. [ABSTRACT FROM AUTHOR]

Cashmere and wool are both natural animal fibers used in the textile industry, but cashmere is of superior quality, is rarer, and more precious. It is therefore important to distinguish the two fibers accurately and effectively. However, challenges due to their similar appearance, morphology, and physical and chemical properties remain. Herein, a terahertz electromagnetic inductive transparency (EIT) metasurface biosensor is introduced for qualitative and quantitative identification of cashmere and wool. The periodic unit structure of the metasurface consists of four rotationally symmetric resonators and two cross−arranged metal secants to form toroidal dipoles and electric dipoles, respectively, so that its effective sensing area can be greatly improved by 1075% compared to the traditional dipole mode, and the sensitivity will be up to 342 GHz/RIU. The amplitude and frequency shift changes of the terahertz transmission spectra caused by the different refractive indices of cashmere/wool can achieve highly sensitive label−free qualitative and quantitative identification of both. The experimental results show that the terahertz metasurface biosensor can work at a concentration of 0.02 mg/mL. It provides a new way to achieve high sensitivity, precision, and trace detection of cashmere/wool, and would be a valuable application for the cashmere industry. [ABSTRACT FROM AUTHOR]

Objectives. A more accurate preoperative prediction of lymph node metastasis (LNM) plays a decisive role in the selection of treatment in patients with laryngeal carcinoma (LC). This study aimed to develop a machine learning (ML) prediction model for predicting LNM in patients with LC. Methods. We collected and retrospectively analysed 4887 LC patients with detailed demographical characteristics including age at diagnosis, race, sex, primary site, histology, number of tumours, T-stage, grade, and tumour size in the National Institutes of Health (NIH) Surveillance, Epidemiology, and End Results (SEER) database from 2005 to 2015. A correlation analysis of all variables was evaluated by the Pearson correlation. Independent risk factors for LC patients with LNM were identified by univariate and multivariate logistic regression analyses. Afterward, patients were randomly divided into training and test sets in a ratio of 8 to 2. On this basis, we established logistic regression (LR), k-nearest neighbor (KNN), support vector machine (SVM), extreme gradient boosting (XGBoost), random forest (RF), and light gradient boosting machine (LightGBM) algorithm models based on ML. The area under the receiver operating characteristic curve (AUC) value, accuracy, precision, recall rate, F1-score, specificity, and Brier score was adopted to evaluate and compare the prediction performance of the models. Finally, the Shapley additive explanation (SHAP) method was used to interpret the association between each feature variable and target variables based on the best model. Results. Of the 4887 total LC patients, 3409 were without LNM (69.76%), and 1478 had LNM (30.24%). The result of the Pearson correlation showed that variables were weakly correlated with each other. The independent risk factors for LC patients with LNM were age at diagnosis, race, primary site, number of tumours, tumour size, grade, and T-stage. Among six models, XGBoost displayed a better performance for predicting LNM, with five performance metrics outperforming other models in the training set (AUC: 0.791 (95% CI: 0.776–0.806), accuracy: 0.739, recall rate: 0.638, F1-score: 0.663, and Brier score: 0.165), and similar results were observed in the test set. Moreover, the SHAP value of XGBoost was calculated, and the result showed that the three features, T-stage, primary site, and grade, had the greatest impact on predicting the outcomes. Conclusions. The XGBoost model performed better and can be applied to forecast the LNM of LC, offering a valuable and significant reference for clinicians in advanced decision-making. [ABSTRACT FROM AUTHOR]

Tonotopic differences in the structure and physiological function, e.g., synapse number, membrane properties, Ca2+ channels, Ca2+ dependence of exocytosis and vesicle pool replenishment of inner hair cells (IHCs) along the longitudinal cochlear axis have recently been discovered, suggesting different gene expression patterns of IHCs. To determine whether IHCs present different gene expression patterns along the longitudinal cochlear axis, apical and basal IHCs were collected separately using the suction pipette technique from adult mouse cochleae for RNA-seq and genome-wide transcriptome analysis. We found 689 annotated genes showed more than 2-fold increase in expression. Interestingly, 93.4% of the differentially expressed genes (DEGs) was upregulated in apical IHCs. Although a subset of genes that related to IHC machinery and deafness were found to be differentially expressed, a gradient of gene expression was indeed detected in Ocm, Pvalb, Prkd1, Fbxo32, Nme2 , and Sncg , which may play putative roles in the Ca2+ buffering and survival regulation. The expression of these genes was validated by real-time quantitative PCR (RT-qPCR) or immunostaining. We conclude that IHCs from different mouse cochlear longitudinal position have different gene expression profiles. Our data might serve as a valuable resource for exploring the molecular mechanisms underlying different biological properties as well as the survival regulation of IHCs. [ABSTRACT FROM AUTHOR]

The excited state intramolecular proton transfer (ESIPT) dynamics and photophysical properties of 4-( N , N -dimethylamino)-3-hydroxyflavone (DMAF) in acetonitrile (ACN) and ethanol (EtOH) were investigated by density-functional theory (DFT) and time-dependent density-functional theory (TDDFT) methods at B3LYP/6-31G (d,p) level. The calculation results show that hydrogen bond in the first excited state (S 1 ) is strengthened, which can facilitate the process of proton transfer. The absorption and emission spectra obtained through the vertical excitation energies agree well with the experiment, which confirm the rationality of the choice of theoretical methods. In addition, the frontier molecular orbitals (MOs) analysis indicates the intramolecular charge transfer, which can reveal the tendency of ESIPT reaction. In order to explore the mechanism of the ESIPT process, the potential energy curves of the ground state (S 0 ) and the S 1 state have been constructed. Based on the energy potential barrier of 3.48 kcal/mol for DMAF molecule and 5.48 kcal/mol for 4-( N , N -dimethylamino)-3-hydroxyflavone/ethanol (DMAF-EtOH) complex in the S 1 state, we can find that the proton transfer occurs more easily in acetonitrile solvent. [ABSTRACT FROM AUTHOR]

Developing drugs that can effectively block STAT3 activation may serve as one of the most promising strategy for cancer treatment. Currently, there is no putative STAT3 inhibitor that can be safely and effectively used in clinic. In the present study, we investigated the potential of dihydroartemisinin (DHA) as a putative STAT3 inhibitor and its antitumor activities in head and neck squamous cell carcinoma (HNSCC). The inhibitory effects of DHA on STAT3 activation along with its underlying mechanisms were studied in HNSCC cells. The antitumor effects of DHA against HNSCC cells were explored both in vitro and in vivo. An investigation on cooperative effects of DHA with cisplatin in killing HNSCC cells was also implemented. DHA exhibited remarkable and specific inhibitory effects on STAT3 activation via selectively blocking Jak2/STAT3 signaling. Besides, DHA significantly inhibited HNSCC growth both in vitro and in vivo possibly through induction of apoptosis and attenuation of cell migration. DHA also synergized with cisplatin in tumor inhibition in HNSCC cells. Our findings demonstrate that DHA is a putative STAT3 inhibitor that may represent a new and effective drug for cancer treatment and therapeutic sensitization in HNSCC patients. [ABSTRACT FROM AUTHOR]

Although the expression of tumor necrosis factor receptors (TNFRs) has been associated with clinicopathologic features of some other cancers, their roles in hypopharyngeal squamous cell carcinoma (HPSCC) have not been documented. Forty-five HPSCC specimens were analyzed for the expression of TNFR1 and TNFR2 and its relationship with clinicopathologic factors. Interaction between the two receptors and its effects on TNF-α was investigated by neutralizing TNFR1 and upregulation of TNFR2. The results indicated that, in HPSCC specimens, the expression of TNFR1 but not TNFR2 is associated with clinical staging, T stage, cervical lymph node metastasis, and histologic grade in HPSCC. In Fadu cells, when conjugating with its receptors, TNF-α mediates proliferation effects, and neutralizing TNFR1 and/or upregulating TNFR2 evokes proliferation-inhibiting and apoptosis-inducing effects and potentiates cisplatin (DDP)-induced growth inhibition and apoptosis induction. In conclusion, interaction of TNFR1 with TNFR2 determines the biological characters of HPSCC, and TNFR1 may dominate this process. Moreover, interaction between the two receptors plays important roles in determining the fates of HPSCC cells and thus may serve as a therapeutic target for developing new therapeutic strategies for HPSCC. [ABSTRACT FROM AUTHOR]

To explore the information seeking behaviors in microblogosphere, the microblog track at TREC 2011 introduced a real-time ad-hoc retrieval task that aims at ranking relevant tweets in reverse-chronological order. We study this problem via a two-phase approach: 1) retrieving tweets in an ad-hoc way; 2) utilizing the temporal information of tweets to enhance the retrieval effectiveness of tweets. Tweets can be categorized into two types. One type consists of short messages not containing any URL of a Web page. The other type has at least one URL of a Web page in addition to a short message. These two types of tweets have different structures. In the first phase, to address the structural difference of tweets, we propose a method to rank tweets using the divide-and-conquer strategy. Specifically, we first rank the two types of tweets separately. This produces two rankings, one for each type. Then we merge these two rankings of tweets into one ranking. In the second phase, we first categorize queries into several types by exploring the temporal distributions of their top-retrieved tweets from the first phase; then we calculate the time-related relevance scores of tweets according to the classified types of queries; finally we combine the time scores with the IR scores from the first phase to produce a ranking of tweets. Experimental results achieved by using the TREC 2011 and TREC 2012 queries over the TREC Tweets2011 collection show that: (i) our way of ranking the two types of tweets separately and then merging them together yields better retrieval effectiveness than ranking them simultaneously; (ii) our way of incorporating temporal information into the retrieval process yields further improvements, and (iii) our method compares favorably with state-of-the-art methods in retrieval effectiveness. [ABSTRACT FROM AUTHOR]

Adenoid cystic carcinoma (ACC) of the external auditory canal (EAC) is a rare tumor. The present study aimed to describe the clinical features and survival of patients with ACC of the EAC. The present retrospective study included 23 patients (mean age, 51.4±15.4 years; 12 males) diagnosed with ACC of the EAC between January 2010 and September 2017 at The First Affiliated Hospital of The Third Military Medical University (Chongqing, China). The median disease course was 24 months. The presenting features were earache in 16 patients, otorrhea in 7 patients, hearing loss in 5 patients, feeling of aural fullness in 2 patients and EAC mass in 4 patients. Tumor stage was T1 in 13 patients, T2 in 3 patients, T3 in 3 patients and T4 in 4 patients. Among patients with T1 tumors, 5 underwent en bloc external EAC resection; 3 underwent local EAC resection; 1 underwent en bloc EAC resection and superficial parotidectomy; 1 underwent subtotal temporal bone resection for postoperative recurrence; Among patients with T4 tumors, 1 underwent extended temporal bone resection, right parotidectomy, right resection of middle cranial fossa tumors and right resection of temporomandibular joint capsule. 1 underwent subtotal temporal bone resection. Among these 15 patients who underwent surgery, 2 received postoperative radiotherapy, 1 received postoperative chemotherapy, 5 received postoperative chemo-radiotherapy, and 7 did not receive postoperative chemo-radiotherapy. The 3- and 5-year cumulative survival rates of the 23 patients were 47.8% and 17.4%, respectively. Survival may have been improved in patients who received postoperative chemo-radiotherapy and early diagnosis may be the key to improving survival., (Copyright: © Jiang et al.)

Background/aim: Lymph node density is a parameter used to more accurately predict tumor recurrence and patient survival. However, its association with surgical outcome in pyriform sinus carcinoma remains unclear. The purpose of this study was to assess the prognostic value of lymph node density in advanced pyriform sinus carcinoma., Patients and Methods: A total of 87 patients with pyriform sinus carcinoma treated between 2008 and 2015 were enrolled. Then, 5-year overall survival, 5-year disease-specific survival, 5-year disease-free survival, and 5-year regional recurrence-free survival were utilized to assess the prognostic significance of lymph node density., Results: With a median follow-up period of 31.8 months, 5-year overall survival, disease-specific survival, disease-free survival, and regional recurrence-free survival were 37.9%, 46.0%, 41.4%, and 54.0%, respectively. Univariate analysis revealed that lymph node density ≥ 0.093 was a significant predictor of poor 5-year overall survival ( P = .005), disease-specific survival ( P = .008), disease-free survival ( P = .0013), and regional recurrence-free survival ( P = .003). Furthermore, multivariate analysis demonstrated that lymph node density was negatively associated with adverse 5-year overall survival (hazard ratio = 1.62, 95% CI: 1.15-2.29, P = .006), disease-specific survival (hazard ratio = 1.86, 95% CI: 1.24-2.80, P = .003), disease-free survival (hazard ratio = 0.45, 95% CI: 0.24-0.85, P = .014), and regional recurrence-free survival (hazard ratio = 2.97, 95% CI: 1.43-6.17, P = .004)., Conclusion: Taken together, these results reveal that lymph node density is a powerful prognostic factor for patients with T3 and T4 pyriform sinus carcinoma, and the median lymph node density cutoff values ≥ 0.093 are associated with a greater risk of recurrence and poorer survival.

Although the expression of tumor necrosis factor receptors (TNFRs) has been associated with clinicopathologic features of some other cancers, their roles in hypopharyngeal squamous cell carcinoma (HPSCC) have not been documented. Forty-five HPSCC specimens were analyzed for the expression of TNFR1 and TNFR2 and its relationship with clinicopathologic factors. Interaction between the two receptors and its effects on TNF-α was investigated by neutralizing TNFR1 and upregulation of TNFR2. The results indicated that, in HPSCC specimens, the expression of TNFR1 but not TNFR2 is associated with clinical staging, T stage, cervical lymph node metastasis, and histologic grade in HPSCC. In Fadu cells, when conjugating with its receptors, TNF-α mediates proliferation effects, and neutralizing TNFR1 and/or upregulating TNFR2 evokes proliferation-inhibiting and apoptosis-inducing effects and potentiates cisplatin (DDP)-induced growth inhibition and apoptosis induction. In conclusion, interaction of TNFR1 with TNFR2 determines the biological characters of HPSCC, and TNFR1 may dominate this process. Moreover, interaction between the two receptors plays important roles in determining the fates of HPSCC cells and thus may serve as a therapeutic target for developing new therapeutic strategies for HPSCC.