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By using image analysis technology and automatic control technology, the artificial intelligence technology was applied to the detection of unsound wheat kernels. The automatic, rapid and nondestructive detection instrument for unsound wheat kernels was developed. Through the verification of accuracy, repeatability, stability, difference between two instruments and other related performance parameters, the results showed that the instrument had stable performance. The accuracy, repeatability, stability and difference between two instruments met the requirements of industry standards. The operation was simple, and the detection speed was fast. It can overcome the problems of strong subjectivity, poor repeatability and poor inspection consistency among different personnel with manual checking, achieving the automatic and rapid nondestructive testing of unsound wheat kernels, and meeting the testing demand of grain collection and storage enterprises, processing enterprises and inspection agencies.

Objective To investigate the association between whole blood iron, copper and their interaction with cardiovascular diseases (CVD). Methods A cohort-based case control study was conducted. Cases were 93 males with CVD in the Kailuan cohort who participated in the follow-up in 3 hospitals in 2017-2018. During the same period, 372 males with non-CVD who were 1∶4 individual matched by age and labor type were selected as controls. The concentration of blood iron and copper was determined by inductively coupled plasma mass spectrometry. Conditional logistic regression models were used to estimate the association between blood iron and copper and CVD, respectively and elastic-Net regression models to estimates interaction between the two metals and CVD. Results The whole blood iron concentration in the cases was significantly higher than the controls, while blood copper concentration was lower than the controls (both P＜0.001). After adjusting for age, smoking, drinking, overweight, hypertension, diabetes, anemia, hyperlipidemia, and high sensitivity C-reactive protein, the participants with higher iron increase 3.17 times (OR=4.17, 95% CI: 2.23-7.79, P＜0.001) risk of CVD than those with lower iron, and those with lower copper increase 3.26 times (OR=4.26, 95% CI: 1.73-10.45, P＜0.01) risk than those with the higher copper. Adaptive Elastic-net regression analysis showed that it under the simultaneous exposure of higher iron and lower copper, the risk of CVD with environment risk score ＞0.232 was 8.96 times (OR=8.96, 95% CI: 4.47-17.95, P＜0.001) than the score ≤0.232. Conclusions Higher iron and copper deficiency may be independent risk factors for CVD. Environment risk score could be a good indicator of simultaneous exposure of blood iron and copper, which should have a better predictive value of CVD.

Objective To explore the effectiveness of team-based learning(TBL) methods in internal medicine. Methods The study enrolled volunteer medical students of grade 2014 from Peking Union Medical College who were in internal medicine clerkship and had a TBL course every week. After four-month teaching, anonymous questionnaires were used to investigate students' feedback on the learning method, and then statistics and evaluation were conducted. Results A total of 30 valid questionnaires were received, and more than 50% of the students believed that TBL teaching could help them grasp the professional knowledge and improve clinical abilities. Through the students' feedback, TBL in promoting independent thinking, ability to communicate with patients’ families, medical skills, professional knowledge learning, etc., the proportion of definite agreement and agreement were 100%; In team cooperation, expression ability and independent learning ability, etc., the proportion of definite agreement and agreement were 90.0%-96.7%. In addition, the stimulating interest in learning, easy to master the knowledge and skills, totally proportion of definite agreement and agreement were less than 90%, which need to beimproved in the future. Conclusions TBL teaching may not only improve the students' learning enthusiasm and learning outcomes, but also strengthen the students' interpersonal communication capacity and team spirit. This method may be shared by other education institutions.

A total synthesis strategy was developed for the synthesis of luotonin A, B and their analogues using synergistic FeCl3/KI‐catalyzed oxidative cyclization. This protocol utilizes cheap and widely available N‐propargyl 2‐methyl‐quinazolinones and arylamines under mild conditions, and it has a wide substrate scope and high atom economy. Different natural products (luotonin A, B and derivatives) can be synthesized via a unique switchable approach. Further transformations from luotonin B to luotonin E and structural modification of natural products demonstrate the potential applications of this method. Moreover, camptothecin can also be modified with the reported protocol to afford the hydroxyl‐substituted product. [ABSTRACT FROM AUTHOR]

The effect of chlorella vulgaris on corrosion behavior of Mg-3Y-1.5Nd alloy in f/2 culture medium was studied by means of X-ray diffraction, scanning electron microscope, energy dispersive analysis system of X-ray and other electrochemistry test. Results show that the main corrosion products on the surface of alloy with and without chlorella vulgaris are Mg (OH)2,Mg3 (PO4)2 and Mg2 (OH)3Cl; Mg and O are present on the specimen surface, and the content of Mg in culture medium with chlorella vulgaris (29.6%) is lower than that without chlorella vulgaris (39.8%); and corrosive ions invade the loose corrosion product structure and promote further corrosion of the alloy; the high O2 concentration produced by the photosynthesis of chlorella vulgaris results in the increase of local O2 concentration underneath the biofilm, which adds oxygen reduction cathodic currents and enhances corrosion. It is conduded that the average corrosion rate in the presence of chlorella vulgaris is more serious than that in the absence of chlorella vulgaris.

A facile protocol for the synthesis of quinoline formaldehydes via direct oxidative C--H bonds functionalization of methyl-azaheteroarenes in the presence of [I.sub.2]--DMSO has been described. This method is metal-free and easy to operate. This reaction provided a convenient route for the preparation of a range of important quinoline formaldehydes. Key words: metal free, oxidative functionalization, methyl-azaheteroarenes, quinoline formaldehydes, iodine. Nous decrivons une methode de synthese facile pour preparer des formaldehydes derives de la quinoline par fonctionnalisation directe de methylazaheteroarenes via l'oxydation de liaisons C--H en presence d'un melange d'I2 dans le DMSO. Cette methode, simple a realiser, fonctionne sans metaux. La reaction constitue une voie d'acces pratique a une variete de formaldehydes de quinoline importants. [Traduit par la Redaction] Mots-cles : sans metaux, fonctionnalisation oxydante, methylazaheteroarenes, formaldehydes de quinoline, iode., Introduction (Hetero)aryl aldehydes ketones are integral parts of various natural products, and they are widely employed as key synthetic intermediates in pharmaceuticals and organic synthesis. (1) In particular, quinoline formaldehyde [...]

The use of ethephon can achieve early and concentrated the machine-harvested cotton boll opening. The purpose of this study is to analyze the effect of the boll-period shortening on the boll weight, fiber quality, and relationship, when the ethephon was sprayed at different stages of the boll development with a selection of 18 materials. The results showed that when the period of cotton was 47--69 days, spraying ethephon at the age of boll was 40.5--49.7 days, which could advance boll opening by 3.5--5.7 days. It took 64.1--69.7 days for fiber to fully mature under ethephon, while it took 54.8--60.5 days for cotton seed. When boll was opened 1.5--6.2 days earlier, the probability of boll weight and fiber quality decreasing was up to 58.0%--76.5%. To achieve an early opening of the boll, ethephon can be applied at the boll age of 34.8--44.1 days, when the boll weight (< 0.26 g) and fiber quality damage (length reduction < 0.28 mm and fiber strength < 0.30 cN tex--1) at the top of cotton plant are reduced by 5% and 1%, respectively. In addition, the boll period was shortened in some materials, but the boll weight, fiber length, and strength were increased, with the 9.5%--23.5% probability. Therefore, the reasonable use of ethephon in some cotton varieties can shorten the boll period and improve the boll weight and quality. [ABSTRACT FROM AUTHOR]