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The extracurricular innovation laboratories serve vital expansion and valuable complement to the traditional teaching laboratory and play a crucial role in developing students' innovative abilities. Given the variety of experiments conducted, the open management of these laboratories presents significant challenges. This paper examines the issues faced by chemical extracurricular innovation laboratories which are opening to undergraduate students and explores corresponding management approaches involving the enhancement of institutional safeguards, the clarification of safety responsibilities, the optimization of resource allocation and opening up of new management models from managerial perspective. These efforts aim to provide robust support for the cultivation of innovative talents. [ABSTRACT FROM AUTHOR]

In order to efficiently degrade organic pollutants in the water environment, poly（heptazine） structured K intercalated carbon nitride （CN-K） was prepared using KCl and NH4Cl as structural inducers. The prepared CN-K was characterized by transmission electron microscopy（TEM）, X-ray diffraction（XRD）and so on. The prepared CN-K can be applied as an efficient photocatalyst for the visible-light photocatalytic degradation of endocrine disruptor bisphenol A （BPA）. The CN-K possessed 4 times enhancement photocatalytic performance than bulk g-C3N4, where the degradation ratio of BPA were 99.0% under light irradiation for 20 min. Owing to the K+ uniformly distributed in CN-K, crystalline structure endows the ordered electronic transmission channels in CN-K, thus enhanced the efficiency of photo induced charge carriers separation and migration, as well as visible light capture. In addition, this heterogeneous catalyst can be recycled at least five times and the recovered CN-K after the final cycle displayed unchanged photocatalytic degradation efficiency, demonstrating its excellent stability and outstanding reusability. This study highlighted opportunities for the recycling treatment of wastewater. [ABSTRACT FROM AUTHOR]

Objective: To explore the independent risk factors of internal mammary lymph nodes (IMN) metastasis and the risk assessment method of IMN metastasis preoperatively in breast cancer patients with negative IMN in imaging examination, and guide the radiotherapy of IMN in patients with different risk stratification of IMN metastasis. Methods: The clinical and pathological data of 301 breast cancer patients who underwent internal mammary sentinel node biopsy(IM-SLNB) and/or IMN dissection in Shandong Cancer Hospital with negative IMN on CT and/or MRI from January 2010 to October 2019 were analyzed retrospectively. The independent risk factors were analyzed by univariate and multivariate logistic regression, and the independent risk factors of IMN metastasis were used to risk stratification. Results: Among the 301 patients, 43 patients had IMN metastasis, and the rate of IMN metastasis was 14.3%. Univariate analysis showed that vascular tumor thrombus, progesterone receptor (PR) expression, T stage and N stage were associated with IMN metastasis. Multivariate logistic regression analysis showed that tumor located in medial quadrant, positive PR and axillary lymph node metastasis were independent risk factors for IMN metastasis. The risk of IMN metastasis was assessed according to the independent risk factors of the patients: low-risk group is including 0 risk factor, medium-risk group is including 1 risk factor, and high-risk group is including 2-3 risk factors. According to this evaluation criteria, 301 patients with breast cancer were divided into low-risk group (with 0 risk factors), medium-risk group (with 1 risk factor) and high-risk group (with 2-3 risk factors). The IMN metastasis rates were 0 (0/34), 4.3% (6/140) and 29.1% (37/127), respectively. Conclusions: The risk stratification of IMN metastasis according to three independent risk factors of IMN metastasis including tumor located in medial quadrant, positive PR and axillary lymph node metastasis in breast cancer patients can guide the radiotherapy of IMN in newly diagnosed breast cancer patients. For N1 patients, radiotherapy of IMN is strongly recommended when the primary tumor is located in the medial quadrant and/or PR positive. [ABSTRACT FROM AUTHOR]

Objective To evaluated the unplanned coverage dose to the internal mammary chain (IMC) in patient treated with postmastectomy radiotherapy (PMRT). Methods One hundred and thirty eight patients with breast cancer receiving radiotherapy (RT) in our hospital were retrospectively analyzed. Patients were divided into three groups: three-dimensional conformal radiotherapy (3D-CRT) group, forward intensity-modulated radiotherapy (F-IMRT) group and inverse IMRT (I-IMRT) group. The IMC were contoured according to Radiation Therapy Oncology Group (RTOG) consensus, and were not include into the planning target volume (PTV). The incidental irradiation dose to IMG among the three groups and the first three intercostal spaces IMG (ICS-IMC 1-3) were all compared, and explored the relationship between the mean doses (Dmean) of IMG and the OARs (ipsilateral lung and heart). Results The dose delivered to IMC showed no difference in CRT, F-IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). And 10.42%, 2.04%, and 9.76% patients achieved ≥45 Gy when treated with CRT, F-IMRT and I-IMRT. For the IMC dose in the first three intercostal spaces (ICS 1-3), there was no difference to the three treatment plannings. The Dmean,V20, V30, V40, V50 of the ICS-IMC2 and ICS-IMC3 were all obviously superior than ICS-IMC1 for all these three plannings. Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for left breast cancer patients underwent CRT (H= 0.338, P = 0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V20 for ipsilateral lung for all patients (F-IMRT: r = 0.366,P = 0.010;r = 0.318,P = 0.026;I-IMRT; r = 0.427,P = 0.005;r = 0.411,P= 0.008). Conclusions In 3D-CRT, F-IMRT and I-IMRT planning methods, partial patients get IMC irradiated doses that could achieve therapeutic doses. Compared with 3D-CRT, F-IMRT and I-IMRT further reduced the dose of irradiated organs. However, there is no difference in the dose coverage of IMC for the three planned approaches when the IMC made an unplanned target. [ABSTRACT FROM AUTHOR]

Objective To quantify the setup error (SE) in breast cancer patients treated with intensity modulated radiotherapy (IMRT) based on cone beam CT (CBCT), and to explore the feasibility of using several CBCT scans to presume and correct SE in the treatment for breast cancer patients. Methods Eighteen breast cancer patients after breast conserving surgery who underwent whole breast IMRT were included in this study. Three dimensional interfraction motion before and after on-line CBCT-based corrections were quantified. The on-line CBCT-based corrections were performed using automated greyscale match. The system SE (Σ) and random error (σ) were calculated for each patient based on the consecutive multiple online scanning based on CBCT (≥5). The trends in magnitudes of Σ and σwere assessed during the treatment. Results The magnitude variation of Σ was less than 1 mm before and after on-line CBCT-based corrections. As the CBCT scanning times increase (before 10 times), the Σ in anteroposterior (AP) direction was increased significantly, and σin three dimensional directions was also increased after 7 times of CBCT scanning. After on-line CBCT-based corrections, the Σ showed a steady trend by variation near zero for the first 20 times irradiation; but after 20 times, the Σ in AP and superoinferior (SI) directions was increased slightly (less than 0.5 mm), and σdecreased in three-dimensional directions. There were no significant differences for Σ, σand setup margin (SM) before and after on-line CBCT-based corrections in all three directions (P>0.05). Conclusions For breast cancer patients who underwent IMRT after breast conserving surgery, the setup error is relatively stable during the whole irradiation. The first 5 CBCT scans are suitable to presume and correct SE, and also can be used as the right time for adaptive radiotherapy planning revision. [ABSTRACT FROM AUTHOR]