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Catalysts for warm cloud seeding have significant potential for applications in warm cloud catalytic precipitation and fog elimination. In recent years, numerous innovative materials have been developed, each with the potential to be used in warm cloud catalysis. However, a universally recognized ideal formulation has not yet been established. It is necessary to conduct a scientific analysis on the performance of various hygroscopic catalysts under consistent experimental conditions.Therefore, 9 types of typical powdered hygroscopic catalysts are collected, and experiments involving fog chamber and static testing of catalysts are conducted at CMA Key Laboratory of Cloud-precipitation Physics and Weather Modification in May 2023. Fog elimination capabilities and hygroscopic characteristics of various catalysts are comprehensively evaluated and compared. Results indicate that, under the same fog conditions, salt type catalysts demonstrate the shortest time to eliminate fog, and porous composite materials (PCM-100 and PCM-10) are also effective, while fog elimination effects of modified starch, molecular sieves, organic bentonite and sodium bentonite are not obvious after seeding. In static detection, under normal temperature and humidity conditions, CaCl2 exhibits the strongest static hygroscopicity, followed by porous composite materials such as PCM-100 and PCM-10. Composite salt catalysts exhibit strong hygroscopic absorption, whereas the static hygroscopic absorption capacity of other catalysts is not as pronounced. In high humidity conditions, bentonite and molecular sieve catalysts still do not exhibit moisture absorption characteristics. The hygroscopic abilities of CaCl2, PCM-100, and PCM-10 are significantly higher than those of other catalysts. The performance of various catalysts in the fog chamber experiment and static detection is basically consistent.Microstructures of various catalysts with strong hygroscopic properties do not show significant changes after 30 minutes. PCM-10 primarily exists in the form of liquid droplets after standing for 5 minutes and can continue to provide hydration. PCM-100 remains in irregular crystal form after 5 minutes and transforms into droplets after 30 minutes. CaCl2 absorbs moisture rapidly under the microscope, initially existing as liquid droplets for 5 minutes. Subsequently, there are no significant changes, primarily small droplets. Complex salts always form crystals, while the size of liquid droplets formed is larger.It should be noted that, although the hygroscopicity and the ability of fog elimination of various catalysts are important indicators, the dispersibility, corrosiveness and ease of preparation and storage of the catalyst are also important parameters of whether they can be used as efficient warm cloud catalysts. Follow-up research and evaluation of various catalysts will be conducted.

Background The potential risks of long-term use of proton pump inhibitor (PPI) and the potentially inappropriate medication are gradually being taken into account, and PPI deprescribing has been widely recognised, but the situation of long-term use of PPI and the willingness to deprescribing of PPI among the community residents in our country are not yet clear. Objective To understand the current situation of long-term PPI use and PPI deprescribing among community residents, explore its influencing factors and propose improvement measures. Methods From April 2018 to January 2020, a survey was conducted among 389 residents of the Shichahai Community Health Service Center in Xicheng District, Beijing, who had been taking proton pump inhibitors (PPIs) chronically. Data on participants' demographics, PPI usage patterns, concurrent use of nonsteroidal anti-inflammatory drugs (NSAIDs) and/or antiplatelet agents, presence of comorbid chronic diseases, medication quantities, potential for PPI deprescribing, and polypharmacy status were collected via the community electronic health information system and telephone-administered questionnaires. Subsequently, between June and December 2020, telephone interviews were conducted with 92 residents still using PPIs long-term to assess their perceptions regarding prolonged PPI use and attitudes toward deprescribing. Multivariate Logistic regression analysis was employed to identify factors influencing the continuous PPI use exceeding six months among those deemed eligible for deprescribing. Results After excluding individuals who declined to participate, could not be reached, or had not taken PPIs continuously, the final study population consisted of 318 residents who were chronically using PPIs. The mean age of long-term PPI residents was (63.9±12.5) years, 61.0% were female, the mean number of types of comorbid chronic diseases was (3.3±1.4) , and the mean number of medications was (6.1±3.3) , and the majority of the residents were able to carry out PPI deprescribing (231, 72.6%) . The prescribing indications for PPIs to prevent nonsteroidal anti-inflammatory drugs (NSAIDs) and antiplatelet drugs for gastrointestinal damage were the most frequent (202, 63.5%) . Multifactorial Logistic regression analysis showed that residents' age and number of medications were influential factors for taking PPIs continuously for >6 months[OR=1.044, 95%CI (1.016-1.073) ; OR=1.175, 95%CI (1.009-1.376) , P

The lighting intensity of coal mine water storage roadways is uneven and the structured features are obvious. Traditional vision based robot pose recognition methods are not accurate. The single robot positioning techniques such as Adaptive Monte Carlo localization (AMCL) method have significant cumulative errors in the output pose information with the long-term operation of the cleaning robot. It is easy to encounter situations where the coal slurry is not cleaned thoroughly and collides with both sides of the roadway. In order to solve the above problem, a multi-sensor fusion clearance robot pose recognition method based on extended Kalman filtering is proposed. Firstly, the method builds a multi-sensor fusion algorithm framework and establishes models for odometer, inertial measurement devices, and LiDAR data acquisition. Secondly, based on the principle of extended Kalman filtering, an observation equation is established using the angle information of the inertial measurement device. Combined with the odometer pose information, the first fusion of the clearance robot pose matrix is obtained. Then, the position information of the lidar is iterated with the previous pose matrix to obtain the second fused clearance robot pose matrix. Finally, the complementary filtering algorithm is used to process the pose matrix of the clearance robot after two fusion and output the final pose matrix of the clearance robot. The experimental results show that the maximum position error in linear pose recognition is 0.04 m, and the maximum attitude angle error is 0.05 rad. The maximum position error in the simulated roadway experiment is 0.1 m, and the maximum attitude angle error is 0.085 rad. Compared with the AMCL method, the pose recognition method of the warehouse cleaning robot based on extended Kalman filtering shows significant effectiveness in reducing the cumulative error during the operation of the warehouse cleaning robot.

Objective To study the effect of triptolide(TPL)combined with chemotherapy drug doxorubicin(DOX)on apoptosis of human breast cancer cell line MCF-7 and its molecular mechanism. Methods MCF-7 cells were treated with triptolide and different concentrations of doxorubicin alone or in combination. Cell viability was analyzed by CCK-8 method with the combination index calculated. Cell proliferation was detected by plate cloning formation assay. Cell apoptosis and cell cycle were detected by flow cytometry. The expressions of apoptosis-related proteins Bcl-2, Bax, cleaved caspase-3 and proteins in PI3K/AKT signaling pathway were analyzed by Western blot. Results Triptolide combined with different concentrations of doxorubicin significantly inhibited cell proliferation as compared with the doxorubicin group alone after incubation for 24, 48 and 72 hours(P＜0.05). The clone formation was restrained and the cell apoptosis rate was significantly higher(P＜0.01). The expressions of Bax and cleaved caspase-3 was up-regulated, and the expressions of Bcl-2, p-PI3K, p-AKT was down-regulated(P＜0.05). The cells were blocked in S phase after combination treatment of the two drugs(P＜0.05). Conclusions The combination of triptolide and doxorubicin significantly increases the sensitivity of MCF-7 cells to doxorubicin and promotes the apoptosis of cells, which might be related to the inhibition of PI3K/AKT signaling pathway.