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An efficient alkoxyl radical-triggered ring expansion/cross-coupling cascade was developed under cheap metal catalysis. Through the metal-catalyzed radical relay strategy, a wide range of medium-sized lactones (9-11 membered) and macrolactones (12, 13, 15, 18, and 19-membered) were constructed in moderate to good yields, along with diverse functional groups including CN, N3, SCN, and X groups installed concurrently. Density functional theory (DFT) calculations revealed that reductive elimination of the cycloalkyl-Cu(iii) species is a more favorable reaction pathway for the cross-coupling step. Based on the results of experiments and DFT, a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle is proposed for this tandem reaction.

Abstract The vulnerability of the current network has become an urgent problem to be solved. The focus of network protection should be shifted from traditional network protection to the direction of effective recovery even after being attacked and damaged, and then, the concept of resilience came into being. This paper selects physical explosion attacks to establish damaged network. An improved system resilience recovery strategy is established which considers task importance and time efficiency. Aiming at the initial population is too random, easy to mature and with poor solution, this paper improves genetic algorithm by new greedy model in population initialization and head-to-head mutation operator. Simulation shows that the improved genetic algorithm is better and more stable, the improved quotient model is more effective in system resilience recovery measured by index-E proposed in this paper.

AIM: To investigate the effect and mechanism of matrix metalloproteinase(MMPs)inhibitor AG3340 on the migration and invasion ability of retinal pigment epithelial cells-19(ARPE-19)cultured in high glucose(CHG). METHODS: ARPE-19 cells cultured in vitro were divided into four groups: Control group, the glucose at the concentration of 5.6mmol/L in DMEM/F12 medium; HG group, the glucose at the concentration of 30mmol/L was cultured with DMEM/F12 medium; HG+AG3340 group, the cells were pretreated with AG3340 for 12h, and then cultured in DMEM/F12 medium containing 30mmol/L glucose; The mannitol(MA)group, cultured with DMEM/F12 medium of 5.6mmol/L glucose and 24.4mmol/L mannitol, which used as hypertonic control group. The migration ability of cells was detected by wound healing assay, the invasion ability of cells was detected by Transwell assay, and the relative expression levels of MMP-9, MMP-2, fibronectin and collagen Ⅳ were detected by Western blot.RESULTS: The results of wound healing assay showed that compared with the Control group, the cell migration rate of scratching after 24h and 48h in the HG group was significantly increased(all P

PurposeTo review our single-center surgical outcomes of redo operations after failed Rex shunt procedures.MethodsFrom September 2017 to October 2021, a total of 20 patients (11 males, 9 females; median age: 8.6 years) with Rex shunt occlusions were admitted to our hospital. Two of these patients were previously operated on in our hospital, and the remaining 18 were from other centers. All patients underwent repeat operations after detailed preoperative evaluations.ResultsPreoperative wedged hepatic vein portography (WHVP) was conducted for 18 patients. Thirteen patients exhibited well-developed Rex recessus and intrahepatic portal vein during WHPV examination, consistent with the intraoperative exploration results. Fifteen patients (75%, 15/20) underwent redo-Rex shunt, four underwent Warren shunt and one underwent devascularization surgery. During the redo-Rex shunt operations, the left internal jugular veins (IJV) were used as bypass grafts in 11 patients; the intra-abdominal veins were used in 4 patients. The patients were followed up for 12–59 months (mean, 24.8 months). After redo Rex shunts, the grafts were patent in 14 patients (93.3%, 14/15), but 1 graft had thrombosis (6.7%, 1/15). Three patients suffered from postoperative anastomotic stenosis, and all of the stenosis was relieved with balloon dilatations. After re-Rex shunts, esophageal varices and spleen size were substantially reduced, and the platelet count significantly increased. Postoperative graft thrombosis was found in 1 patient after Warren shunt (1/4, 25%), and there was no graft stenosis. Compared with Warren surgery, patients who underwent re-Rex shunt had a significantly higher rate of platelet increase.ConclusionsRedo-rex shunts can be finished in most patients with failed Rex shunts. Re-Rex shunt is a preferred surgical choice after a failed Rex shunt when a good bypass graft is available, and the surgical success rate can reach more than 90%. A suitable bypass graft is essential for a successful redo Rex shunt. Preoperative WHVP is recommended for the design of a redo surgical plan preoperatively.

Abstract Background Controversial evidence regarding the applicability of the IOM’s gestational weight gain (GWG) targets for women with gestational diabetes mellitus (GDM) has been reported. However, little is known about the weight gain rate (WGR) during the second and third trimesters. Moreover, previous studies failed to assess the effect modification of pre-pregnancy BMI because of the limited sample size. Therefore, we aimed to assess the applicability of the IOM recommendation for the WGR in women with GDM in different pre-pregnancy BMI categories. Methods We conducted this retrospective cohort study of 5275 women with GDM who delivered at Guangzhou Women and Children’s Medical Center (GWCMC) between January 2017 and January 2021. Demographic and clinical information was collected from the electronic medical record system. The primary exposure was the WGR in the late second and third trimesters; they were classified as below, within, and above the IOM standard. The outcomes were fetal growth indicators, including large-for-gestational-age (LGA), macrosomia, small-for-gestational-age (SGA), and low birth weight (LBW). The associations between the WGR and such outcomes were assessed using multiple logistic regression. Results A WGR below the IOM standard was associated with the decreased odds of LGA (adjusted OR 0.74; 95% CI 0.49–1.13) and macrosomia (adjusted OR 0.54, 95% CI 0.32–0.92) for women with GDM in the normal weight BMI class. Such decreases were observed greater for women with GDM in the overweight/obese class, with adjusted ORs of 0.34 (95% CI 0.09–0.88) for LGA and 0.31 (95% CI 0.01–0.84) for macrosomia, respectively. No significant difference was observed in the odds ratios of SGA and LBW across the different WGR groups. Conclusion LGA and macrosomia are the main outcomes associated with the WGR in the late second and third trimesters, and a WGR below the IOM standard was associated with a decreased odds of such outcomes compared with a WGR within the IOM standard in women with GDM in the normal weight and overweight/obese classes. Our findings suggest that a stricter WGR target than that of the current IOM standard may be more beneficial for women with GDM.

The effects of vibratory peening (VP), shot peening (SP), and SP followed by vibratory finishing (SPVF) on the surface and fatigue properties of Ti‐6Al‐4 V were compared to conventional low‐stress grinding (LSG). VP processing produced seven times smoother surface finish than SP and 66% deeper compressive residual stresses (CRS) but with 12% lower magnitudes. SPVF produced optimal surface properties with a perfectly flat surface and CRS‐like SP. All three mechanical surface treatments generated similar fatigue life improvements (108–122%) over LSG when the cyclic stress was below the yield stress. Above the yield stress, most of the CRS relaxed during the first cycle in VP specimens, resulting in up to 97% fatigue life improvement over LSG. The CRS relaxed more gradually in SP specimens leading to larger (up to 239%) fatigue life improvement. This shows the need to amplify CRS magnitudes produced in VP to maximize fatigue life improvement. Highlights: Vibratory peening (VP) provides 7X better surface finish than shot peening (SP).VP generates 66% deeper compressive residual stresses (CRS) compared to SP.VP increases fatigue life up to 122% relative to low‐stress grinding.SP generates higher CRS and longer fatigue life above the yield stress than VP. [ABSTRACT FROM AUTHOR]

Mild and inexpensive copper‐catalyzed aromatization‐driven ring‐opening amination and oxygenation of spiro dihydroquinazolinones are presented, respectively. These protocols provide facile and atom‐economical access to the aminated and the carbonyl‐containing quinazolin‐4(3H)‐ones in good yields with good functional group compatibility, which are difficult to obtain by conventional methods. Remarkably, a telescoped procedure involving the condensation and the ring‐opening/functionalization for simple cycloalkanone was found to be accessible. Mechanistic studies suggest a radical pathway for this transformation. [ABSTRACT FROM AUTHOR]

The seedling retrieval mechanism is a crucial component of fully automatic transplanting machines, significantly influencing the quality, reliability, and efficiency of the transplanting process. Nonetheless, the existing seedling retrieval mechanisms in current transplanting machines exhibit several deficiencies, including substantial damage to seedlings and inadequate retrieval accuracy. To overcome these challenges, we propose an integrated approach combining pneumatic and mechanical techniques to further improve performance. By employing a lower thimble elevation and clamping mechanism, alongside a mathematical model based on the seedling removal process, this method ensures precise seedling extraction and minimizes damage to the root system and substrate. The novelty of this study lies in its ability to reduce the adhesion between seedlings and the holes of the plug plate, thereby minimizing non-destructive extraction of the seedlings and preserving the integrity of the matrix, which is essential for ensuring healthy seedling growth. Moreover, the optimization of the seedling retrieval trajectory enhances the accuracy of the seedling retrieval mechanism while also meeting the requisite speed requirements. Experimental results indicate that at a rate of 72 seedlings per minute, the extraction success rate reached 94.90%, and the casting success rate was 98.53%. The seedling injury rate was only 1.95%, resulting in an overall success rate of 91.69%. These findings confirm that the device meets operational efficiency requirements and delivers effective performance. [ABSTRACT FROM AUTHOR]

AIM:To evaluate the efficacy and safety of dexamethasone intravitreal implant for the treatment of noninfectious refractory uveitis and analyze its influence on application and dose of systemic corticosteroids and immunosuppressive agent.METHODS: This was a retrospective, case series study conducted between January 2018 and September 2019, the patients with noninfectious refractory uveitis and treated with intravitreal implantation of dexamethasone intravitreal implant were included. The best corrected visual acuity(BCVA), central retinal thickness(CRT), vitreous haze score, and intraocular pressure(IOP)at 1mo, 2mo, 4mo and 6mo after the implantation of dexamethasone intravitreal implant were compared with the baseline. Meanwhile, the dosage of corticosteroids and immunosuppressive agent used before and after the implantation of dexamethasone was also evaluated. The data was displayed as mean±standard deviation and analyzed using the paired t-test.RESULTS: A total of 19 patients(21 eyes)were included in the present study. The mean baseline BCVA of the included patients was 0.671±0.469, while the mean CRT was 369.667±177.100μm, and the mean intraocular pressure(IOP)was 14.252±3.181mmHg. One month, 2mo, 4mo and 6mo after the injection of Ozrudex, BCVA was significantly improved compared with the baseline(P