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A new copper‐catalyzed sp3‐carbon radical/halogen radical cross‐coupling strategy for the formation of C(sp3)‐X bond is described. This provides a general method for synthesis of α‐halogenated and α,α‐dihalogenated‐1,3‐dicarbonyl compounds using sodium halides as halogen source under mild conditions. [ABSTRACT FROM AUTHOR]

JPZ acknowledges financial support from the National Natural Science Foundation of China (No. 21172163, 21472133), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and Key Laboratory of Organic Synthesis of Jiangsu Province (KJS1749). [ABSTRACT FROM AUTHOR]

Steric hindrance due to bulky groups adjacent to the position of attack by the trifluoromethyl radical decreases the yields. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the use of virtual reality-based infrared pupillometry (VIP) to detect individuals suffering long COVID., Design: Prospective, case-control cross-sectional study., Participants: Participants aged 20-60 were recruited from a community eye screening programme., Methods: Pupillary Light Responses (PLR) were recorded in response to 3 intensities of light stimuli (L6, L7 and L8) using a virtual reality head-mount display (VR-HMD). 9 PLR waveform features for each stimulus, were extracted by 2 masked observers and statistically analyzed. We also use various methods on the whole PLR waveform including trained, validated and tested (6:3:1) by machine learning models including Multi-layer Perceptron, Support Vector Machine, K-nearest Neighbors, Logistic Regression, Decision Tree, Random Forest and Long Short-Term Memory (LSTM) models for two and three-class classification into long-COVID (LCVD), post-COVID (PCVD) or control., Main Outcome Measures: Accuracies/AUC of individual or combination of PLR features and ML models using PLR features or whole pupillometric waveform., Results: PLR from a total of 185 subjects including 112 LCVD, 44 PCVD and 29 age/sex-matched controls were analysed. Models examined the independent effects of age and sex. Constriction Time(CT) after the brightest stimulus(L8) is significantly associated with LCVD status(two-way ANOVA, false discovery rate(FDR)<0.001; multinominal logistic regression, FDR<0.05). The overall accuracy/AUC of CT-L8 alone in differentiating LCVD from control or from PCVD were 0.7808/0.8711 and 0.8654/0.8140 respectively. Using cross-validated backward stepwise variable selection, CT-L8, CT-L6, Constriction Velocity(CV)-L6 were most useful to detect LCVD while CV-L8 for PCVD from other groups. The accuracy/AUC of selected features were 0.8000/0.9000 (control versus LCVD) and 0.9062/0.9710 (PCVD versus LCVD), better than when all 27 pupillometric features were combined. An LSTM model analyzing whole pupillometric waveform achieved the highest accuracy/AUC at 0.9375/1.000 in differentiating LCVD from PCVD and a slightly lower accuracy of 0.7838 for three-class classification (LCVD-PCVD-control)., Conclusions: We reported, for the first time, specific pupillometric signatures in differentiating LCVD from PCVD or control subjects using a VR-HMD. Combining statistical methods to identify specific pupillometric features and ML algorithms to analyse the performance further enhance the performance of VIP as a non-intrusive, low-cost, portable and objective method to detect and monitor long COVID., (Copyright © 2024. Published by Elsevier Inc.)

Background: The diagnosis of small bowel diseases is challenging and device assisted enteroscopy (DAE) is a technique for visualizing the entire small bowel. DAE is considered as a safe procedure and the reported rate of adverse events associated with DAE in the literature is low., Objective: The present study tried to investigate the actual incidence of AP after DAE with a systematic review and meta-analysis of available relevant studies., Methods: Studies were searched through the PubMed, EMBASE, and Cochrane library databases. The following data were extracted from all eligible studies: author, country, publication year, publication type, study design, type of DAE used, route of DAE, number of patients with AP after DAE, and number of patients with hyperamylasemia after DAE.A random-effects model with RStudio version 4.2.0 was performed in all analyses. Heterogeneity was assessed using the I 2 test. The risk of bias was assessed by the Newcastle-Ottawa Scale criteria and the publication bias was assessed by the Egger test., Results: Twenty three studies involving a total of 11145 patients were included in the analysis. The overall, pooled AP rate after DAE was 1% (95% CI:0-1%). There was significant heterogeneity among the studies (I 2 = 65%; P < 0.01).The pooled AP rate was 1% (95% CI:0-2 %)in peroral route group. The pooled proportion of patients having hyperamylasemia after DAE was 29% (95% CI: 16-46%).Among the patients who had hyperamylasemia AP were identified in 2% (95% CI: 0-6%) of patients., Conclusion: The incidence of AP after DAE is about 1%. Hyperamylasemia is a common change in the patients undergoing DAE and only 2% of the patients with hyperamylasemia present with AP., Competing Interests: The authors declare that research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Xiao-Dong Shao MD, Hao-Tian Shao MD, Le Wang MD, Yong-Guo Zhang MD, Ye Tian MD, Cheng-Kun Li MD.)

A Cu I -catalyzed cross-coupling of alkyl- and phosphorus-centered radicals for C(sp 3 )-P bond formation is introduced. Diacyl peroxides, generated in situ from aliphatic acids and H 2 O 2 , serve as a source for alkyl radicals and also an initiator for the generation of phosphorus radicals from H-P(O) compounds.

A copper-catalyzed radical C sp 3 -H/P(OR) 3 cross-coupling reaction for the formation of C sp 3 -P bonds is described. A range of 1,3-dicarbonyl compounds and trialkylphosphites were coupled in this fashion to give the corresponding products in moderate to good yields. This protocol provides direct access to α-phosphonyl 1,3-dicarbonyl compounds.