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Abstract [Objective] Callose is a beta-1, 3-bonded glucan that forms a wall structure, which occurs only in certain tissues. When degrading prematurely or delayed, it may lead to pollen abortion. Examining the dynamics of callose deposition is important for understanding the mechanism of male sterility and its application. [Methods] The fertile line ‘Ningqi No.1’ and sterile line ‘Ningqi No.5’ of Lycium barbarum L. were studied using semi-thin section technique, and callose was labeled with aniline blue and periodic acid- Schiff stain (PAS). The dynamic characteristics of callose in fertile and sterile anthers of L. barbarum at different developmental stages were compared under optical microscope, and the influence of callose on anther abortion of sterile line was analyzed. [Results] In the microspore mother stage, the extracellular deposits of fertile and sterile anthers formed an uneven thick callose wall, and the fluorescence reaction showed that the callose wall gradually was thickened after meiosis forming a tetrad. With the further development of anthers, the extracellular callose wall in fertile anthers gradually disintegrated and disappeared, releasing 4 microspores. However, in sterile anthers, the callose wall outside the tetrad was thickened continuously, and there was no sign of degradation. Until flowering, the small spores in the anther chamber still existed in the state of tetrad, and the callose wall was still wrapped around the deformed and disintegrated tetrad. [Conclusion] Abnormal callose degradation was the structural cause of pollen abortion in Ningxia wolfberry. This study further analyzed the reason why the callose wall of the sterile line tetrad did not degrade, and provides a theoretical basis for analyzing the male sterility mechanism of L. barbarum L..

The integrated dual-channel pathway is regarded as an ideal process for photocatalytic H2O2 production. However, it is a key scientific challenge to rationally design photocatalysts for achieving H2O2 production through such a dual-channel pathway. Here, we designed surface oxygen vacancy-modified BiOIO3 (BIO-OVs-x) with spatially separated redox reaction centers by constructing a facet heterojunction for directly utilizing O2 and H2O to photosynthesize H2O2. Under white light irradiation, optimal BIO-OVs-2 exhibited the highest H2O2 production rate of 215.5 μmol g–1 h–1, which was 3 times more than that of BiOIO3, as well as an apparent quantum yield of 5.76% at 350 nm. Photoelectrochemical experiments confirmed that the introduction of oxygen vacancies boosted the efficiency of charge separation and transfer and adjusted the band structure. Control experiments and theoretical studies elucidated photocatalytic reaction active sites and the charge transport mechanism of BIO-OV catalysts. More importantly, the introduction of oxygen vacancies in BiOIO3 reduced the free energy for OH* of the water oxidation reaction and promoted the occurrence of the water oxidation reaction. This work provides a valuable basis for the fine design of a high-performance photocatalyst and for understanding the mechanism of hydrogen peroxide production. [ABSTRACT FROM AUTHOR]

Background: Conventional MRI staging can be challenging in the preoperative assessment of rectal cancer. Deep learning methods based on MRI have shown promise in cancer diagnosis and prognostication. However, the value of deep learning in rectal cancer T‐staging is unclear. Purpose: To develop a deep learning model based on preoperative multiparametric MRI for evaluation of rectal cancer and to investigate its potential to improve T‐staging accuracy. Study Type: Retrospective. Population: After cross‐validation, 260 patients (123 with T‐stage T1‐2 and 134 with T‐stage T3‐4) with histopathologically confirmed rectal cancer were randomly divided to the training (N = 208) and test sets (N = 52). Field Strength/Sequence: 3.0 T/Dynamic contrast enhanced (DCE), T2‐weighted imaging (T2W), and diffusion‐weighted imaging (DWI). Assessment: The deep learning (DL) model of multiparametric (DCE, T2W, and DWI) convolutional neural network were constructed for evaluating preoperative diagnosis. The pathological findings served as the reference standard for T‐stage. For comparison, the single parameter DL‐model, a logistic regression model composed of clinical features and subjective assessment of radiologists were used. Statistical Tests: The receiver operating characteristic curve (ROC) was used to evaluate the models, the Fleiss' kappa for the intercorrelation coefficients, and DeLong test for compare the diagnostic performance of ROCs. P‐values less than 0.05 were considered statistically significant. Results: The Area Under Curve (AUC) of the multiparametric DL‐model was 0.854, which was significantly higher than the radiologist's assessment (AUC = 0.678), clinical model (AUC = 0.747), and the single parameter DL‐models including T2W‐model (AUC = 0.735), DWI‐model (AUC = 0.759), and DCE‐model (AUC = 0.789). Data Conclusion: In the evaluation of rectal cancer patients, the proposed multiparametric DL‐model outperformed the radiologist's assessment, the clinical model as well as the single parameter models. The multiparametric DL‐model has the potential to assist clinicians by providing more reliable and precise preoperative T staging diagnosis. Evidence Level: 3 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

In this paper, FeSm/BC composites were prepared using coconut shell biochar (BC) as the carrier. FeSm on FeSm/BC is preferentially oriented along the (001) crystal plane and exhibits a uniform honeycomb morphology. It has a high specific surface area and a small pore size distribution, which is more suitable as a heavy metal ion removal material. The results show that Cr(VI) can be almost completely removed within 120 min under acidic conditions with an initial concentration of 10 mg/L of Cr(VI), a temperature of 20 °C, and a dosage of 0.6 g/L of adsorbent. Where pH was the main factor influencing the removal of Cr(VI):pH affects Cr(VI) removal by changing the form of Cr(VI) in the solution, adsorption free energy, redox potential, charged species on FeSm/BC surface, and the reduction properties of Fe2+ and S2−, low pH value is more favorable for Cr(VI) removal. Coexisting anions in solution inhibit Cr(VI) removal due to competitive adsorption, but coexisting cations have no effect. The adsorption process of Cr(VI) by FeSm/BC follows the pseudo-second-order kinetics and Langmuir adsorption isotherm model, indicating that the adsorption process is a monolayer surface adsorption controlled by the chemical adsorption mechanism and involves electron sharing or exchange between adsorbent and adsorbate. Thermodynamic study shows that the adsorption process is a spontaneous entropy-increasing process, and raise the temperature is beneficial to the adsorption. The removal of Cr(VI) by FeSm/BC is the synergistic effect of adsorption, reduction, and co-precipitation. [ABSTRACT FROM AUTHOR]

For a domestic copper-sulfur polymetallic ore containing 0.45% Cu, 33.65% S, 1.45 g/t Au and 41.02 g/t Ag, an selective flotation flowsheet consisting of one roughing, two scavengings and two cleanings was adopted in the copper circuit. A copper concentrate with Cu grade of 20.39% and Cu recovery of 81.00% was obtained by using thiourea + MOS-2 as a combined collector. The sulfur loop adopts the flotation flowsheet of one roughing and two scavengings and uses regulator sulfuric acid and collector butyl xanthate. Through the closed-circuit tests, S grade of sulfur concentrate is 49.68% and S recovery is 96.24%, and the comprehensive recovery of associated gold and silver is 91.71% and 95.17% respectively. The test index is good, which has reference significance for the development and utilization of this resource. [ABSTRACT FROM AUTHOR]

Exposure of gingival margin is frequently observed in anterior teeth aesthetic restoration. How to obtain an expected result is a significant challenge during prosthodontic treatment. The present article discussed gingival bio-type, conditions of periodontal tissue, location of margin of restoration, gingival retraction, and provisional restoration, etc. which would affect the final aesthetic outcome of anterior teeth restorations. The aim of this article is to figure out how to effectively avoid the exposure of gingival margin in anterior teeth aesthetic restoration, and to improve the finally aesthetic outcome of anterior teeth restoration. [ABSTRACT FROM AUTHOR]

Exposure of gingival margin is frequently observed in anterior teeth aesthetic restoration. How to obtain an expected result is a significant challenge during prosthodontic treatment. The present article discussed gingival biotype, conditions of periodontal tissue, location of margin of restoration, gingival retraction, and provisional restoration, etc, which would affect the final aesthetic outcome of anterior teeth restorations. The aim of this article is to figure out how to effectively avoid the exposure of gingival margin in anterior teeth aesthetic restoration, and to improve the finally aesthetic outcome of anterior teeth restoration.