A one‐pot approach for the asymmetric synthesis of C2‐tetrasubstituted indolin‐3‐ones from 2‐substituted indoles was developed via merging transition metal catalysis with organocatalysis. This ...strategy involves two processes, including CuI catalyzed oxidative dearomatization of 2‐substituted indoles using O2 as green oxidant, and followed by an proline‐promoted asymmetric Mannich reaction with ketones or aldehydes. A series of C2‐tetrasubstituted indolin‐3‐ones were obtained in 35–86% yields, 2:1‐>20:1 dr and 48–99% ee. Moreover, the synthetic 2‐tetrasubstituted indolin‐3‐ones could be easily transformed into 1H‐1,3 oxazino 3,4‐aindol‐5(3H)‐ones via a 4+1 cyclization process. In addition, the synthetic compound 3 s show certain antibacterial activity against S. aureus ATCC25923 and multi‐drug resistance bacterial strain of S. aureus (20151027077) and its MIC values up to 8 μg/mL and 16 μg/mL, respectively.
With the research of machine learning technology and big data intelligent processing technology in engineering application becoming more and more mature, people gradually combine machine learning ...technology and big data intelligent processing technology. Aiming at the problem of innovative employment in colleges and universities, this paper proposes a dynamic decision tree algorithm based on these two technologies and constructs a dynamic model of graduates’ behavior. Through the analysis of dynamic decision tree algorithm, a big data analysis system is formed. Finally, simulation experiments verify whether the dynamic model can correctly reflect the behavior of college graduates. The results show that the big data integration system based on big data and dynamic decision tree algorithm has high adaptability. Incremental adaptive optimization of the traditional decision tree model can significantly improve the prediction effect and prediction time of dynamic data and provide theoretical support for the industrialization and social significance of big data technology. The dynamic decision tree algorithm of college employment proposed in this paper has good predictability and provides a certain theoretical reference for college graduates’ entrepreneurship.
In this paper, by utilizing Wang's Harnack inequality with power and the Banach fixed point theorem, the weak well-posedness for McKean-Vlasov SDEs with integrable drift is investigated. In addition, ...by Banach's fixed theorem, the existence and uniqueness of invariant probability measure for symmetric McKean-Vlasov SDEs and stochastic Hamiltonian system with integrable drifts are obtained.
•The prevalence of anxiety and depression symptom was 7.7% and 12.2%, respectively.•Having confirmed and suspected cases in family members or relatives was associated with the higher risk of ...depression symptom.•Self-reported health condition was strongly associated with risk of anxiety and depression symptom.
: Although studies have suggested experiencing the epidemic of severe infectious diseases increased the prevalence of mental health problems, the association between COVID-19 epidemic and risk of anxiety and depression symptom in college students in China was unclear.
: A large cross-sectional online survey with 44,447 college students was conducted in Guangzhou, China. The Zung's Self-rating Anxiety Scale (SAS) and the Center for Epidemiologic Studies Depression Scale (CES-D Scale) were used to define the anxiety and depression symptom, respectively. Multivariable logistic regression models were used to analyze the association between COVID-19 epidemic and risk of anxiety and depression symptom.
: The prevalence of anxiety and depression symptom was 7.7% (95% confidence interval CI: 7.5%, 8.0%) and 12.2% (95%CI: 11.9%, 12.5%), respectively. Compared with students who reported have not infected or suspected cases in family members and relatives, students who reported having confirmed (OR=4.06; 95%CI: 1.62, 10.19; P = 0.003), and suspected (OR=2.11; 95%CI: 1.11, 4.00; P = 0.023) cases in family members and relatives had higher risk of depression symptom. Additionally, the proportions of students with anxiety and depression symptom reported more demand of psychological knowledge and interventions than those without (P<0.001).
: All the data in this study was collected through online questionnaire, and we did not evaluate the reliability and validity.
: The prevalence of anxiety and depression symptom was relatively low in college students, but the COVID-19 epidemic-related factors might be associated with higher depression symptom risk.
Acute myocardial ischemia/reperfusion (I/R) injury is a significant, unsolved clinical puzzle. In the disease context of acute myocardial infarction, reperfusion remains the only effective strategy ...to salvage ischemic myocardium, but it also causes additional damage. Myocardial I/R injury is composed of four types of damage, and these events attenuate the benefits of reperfusion therapy. Thus, inventing new strategies to conquer I/R injury is an unmet clinical need. A variety of pathological processes and mediators, including changes in the pH, generation of reactive oxygen radicals, and intracellular calcium overload, are proposed to be crucial in I/R-related cell injury. Among the intracellular events that occur during I/R, we stress the importance of protein phosphorylation signaling and elaborate its regulation. A variety of protein kinase pathways could be activated in I/R, including reperfusion injury salvage kinase and survivor-activating factor enhancement pathways, which are critical to cardiomyocyte survival. In addition to serine/threonine phosphorylation signaling, protein tyrosine phosphorylation is also critical in multiple cell functions and survival. However, the roles of protein kinases and phosphatases in I/R have not been extensively studied yet. By better understanding the mechanisms of I/R injury, we may have a better chance to develop new strategies for I/R injury and apply them in the clinical patient care.
The Harnack inequality for stochastic differential equation driven by
G
-Brownian motion with multiplicative noise is derived by means of the coupling by change of measure, which extends the ...corresponding results derived in Wang (Probab. Theory Related Fields 109:417–424) under the linear expectation. Moreover, we generalize the gradient estimate under nonlinear expectation appeared in Song (Sci. China Math. 64:1093–1108).
In this paper, Wang’s Harnack and shift Harnack inequality for a class of stochastic differential equations driven by
G
-Brownian motion are established. The results generalize the ones in the linear ...expectation setting. Moreover, some applications are also given.
Summary
Vibrio alginolyticus threatens both humans and marine animals, but hosts respond to V. alginolyticus infection is not fully understood. Here, functional metabolomics was adopted to ...investigate the metabolic differences between the dying and surviving zebrafish upon V. alginolyticus infection. Tryptophan was identified as the most crucial metabolite, whose abundance was decreased in the dying group but increased in the survival group as compared to control group without infection. Concurrently, the dying zebrafish displayed excessive immune response and produced higher level of reactive oxygen species (ROS). Interestingly, exogenous tryptophan reverted dying rate through metabolome re‐programming, thereby enhancing the survival from V. alginolyticus infection. It is preceded by the following mechanism: tryptophan fluxed into the glycolysis and tricarboxylic acid cycle (TCA cycle), promoted adenosine triphosphate (ATP) production and further increased the generation of NADPH. Meanwhile, tryptophan decreased NADPH oxidation. These together ameliorate ROS, key molecules in excessive immune response. This is further supported by the event that the inhibition of pyruvate metabolism and TCA cycle by inhibitors decreased D. reiro survival. Thus, our data indicate that tryptophan is a key metabolite for the host to fight against V. alginolyticus infection, representing an alternative strategy to treat bacterial infection in an antibiotic‐independent way.
The Vibrio alginolyticus infection causes D. reiro death through virulence factors and septic shock‐associated oxidative stress. The oxidative stress could be relived by tryptophan, which fluxes into the TCA cycle to increase the ATP production. ATP served as the substrates for the production of NADPH, which antagonized the ROS, thus protecting host death from over‐active immune response like ROS.
A 4+3 annulation of 2‐ylideneoxindoles with crotonate‐derived sulfur ylides has been developed. A series of oxepino3,2‐bindoles were prepared in moderate to excellent yields (62‐93%) under mild ...conditions. Moreover, the synthetic oxepino3,2‐b indoles can be further transformed into more complex cyclopropa5,6oxepino3,2‐bindoles via a 2+1 cyclopropanation. In addition, the synthetic compounds show certain antiproliferative activity against K562 and MCF‐7 cells, and its IC50 values for these two kinds of tumor cells up to 5.40±0.88 μM and 18.41±0.50 μM, respectively.
In this paper, we investigate sufficient and necessary conditions for the comparison theorem of neutral stochastic functional differential equations driven by G-Brownian motion (G-NSFDE). Moreover, ...the results extend the ones in the linear expectation case (Bai and Jiang, 2016) and nonlinear expectation framework (Huang and Yang, 2021).
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