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Reducing the cost of RuO2/TiO2 catalysts is still one of the urgent challenges in catalytic HCl oxidation. In the present work, a Ce-doped TiO2 supported RuO2 catalyst with a low Ru loading was developed, showing a high activity in the catalytic oxidation of HCl to Cl2. The results on some extensive characterizations of both Ce-doped TiO2 carriers and their supported RuO2 catalysts show that the doping of Ce into TiO2 can effectively change the lattice parameters of TiO2 to improve the dispersion of the active RuO2 species on the carrier, which facilitates the production of surface Ru species to expose more active sites for boosting the catalytic performance even under some harsh reaction conditions. This work provides some scientific basis and technical support for chlorine recycling.
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Cério , Ácido Clorídrico , Oxirredução , Titânio , Titânio/química , Catálise , Cério/química , Ácido Clorídrico/química , Compostos de Rutênio/química , Cloretos/química , Modelos Químicos , Cloro/químicaRESUMO
A catalytic asymmetric α-hydroxylation of pyridinone-fused lactones, containing the core structure of camptothecin, is described. Development of a novel spiropyrrolidine amide (SPA) derived triazolium bromide organo-cation catalyst is crucial for a highly enantioselective oxidation, which also accommodates a wide array of lactones with various substituents. The resulting tricyclic tertiary alcohol with an oxa-quaternary carbon center can be further applied in the synthesis of SN-38 and irinotecan, two anti-cancer drugs derived from camptothecin.
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A cascade Nazarov cyclization/dicycloexpansions reaction was developed for the precise synthesis of the angularly fused M/5/N (M = 5, 6; N = 4-9, 13) tricyclic skeletons. The prioritized expansion of the first ring played a critical role in the transformations, due to the release of ring strain, and the nature of the substituents present on the substrate is another influencing factor. This pioneering cascade reaction features broad substrates scope (33 examples), short reaction time, exceptional yields (up to 95%), and remarkable regioselectivities (> 20:1). Exploiting the synthetic application of this cascade reaction, we successfully executed a succinct total synthesis of nominal madreporanone for the first time.
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OBJECTIVE: The purpose of this study was to investigate the efficacy and safety of endoscopic ultrasound (EUS)-guided injection of cyanoacrylate (CYA) and transjugular intrahepatic portal shunts (TIPSs) in the treatment of patients with cirrhosis with ruptured gastric varices. METHODS: In this retrospective study, 105 patients with liver cirrhosis and gastric varicose veins who were admitted to the First Affiliated Hospital of Anhui Medical University between April 2018 and April 2023 without nonselective ß-blockers treatment and no portal vein thrombosis were evaluated. The patients were divided into the transjugular intrahepatic portal shunt (TIPS) group (n = 60) and the EUS-CYA group (n = 45) for the purpose of evaluating postoperative rebleeding rates, complications, survival rates, and other factors. RESULTS: During the follow-up, there was no significant difference in the rebleeding rates between the TIPS group and EUS-CYA group within 3 months (5% vs 2.2%; P= 0.825; 10% vs 20%, P= 0.147). However, the TIPS group had significantly lower rebleeding rates than the EUS-CYA group at 6 months (10% vs 33.3%; P= 0.030) and 1 year or longer (11.7% vs 42.2%; P < 0.01). In terms of hepatic encephalopathy, the incidence rate of the TIPS group was significantly higher than that of the EUS-CYA group (20% vs 2.2%; P= 0.006). In addition, there was no difference in the survival rates between the two groups (93.3% vs 97.8%; P= 0.552). CONCLUSIONS: TIPS is superior to EUS in preventing rebleeding in patients with ruptured varices of the fundus, but it has a higher incidence of hepatic encephalopathy, and there is no difference in long-term survival between the two groups.
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High mountains harbor a considerable proportion of biodiversity, but we know little about how diverse plants adapt to the harsh environment. Here we finished a high-quality genome assembly for Dasiphora fruticosa, an ecologically important plant distributed in the Qinghai-Tibetan Plateau and lowland of the Northern Hemisphere, and resequenced 592 natural individuals to address how this horticulture plant adapts to highland. Demographic analysis revealed D. fruticosa underwent a bottleneck after Naynayxungla Glaciation. Selective sweep analysis of two pairs of lowland and highland populations identified 63 shared genes related to cell wall organization or biogenesis, cellular component organization, and dwarfism, suggesting parallel adaptation to highland habitats. Most importantly, we found that stronger purging of estimated genetic load due to inbreeding in highland populations apparently contributed to their adaptation to the highest mountain. Our results revealed how plants could tolerate the extreme plateau, which could provide potential insights for species conservation and crop breeding.
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Genoma de Planta , Seleção Genética , Adaptação Fisiológica/genética , AltitudeRESUMO
The application of covalent organic frameworks (COFs) for the photocatalytic reduction of CO2 is mostly limited by severe charge recombination and low sunlight utilization. Herein, a triazine-based COF with an electron-rich and large π-conjugated system (TCOF) was employed as a building block and integrated with CuInS2 (CIS) to construct a noble-metal-free and high-efficiency photocatalyst for CO2 reduction. The in situ growth of CIS nanosheets on TCOF creates a p-n heterojunction, named CIS@TCOF. Compared with TCOF, the CIS@TCOF heterostructure exhibits a dramatically boosted photocatalytic performance in the reduction of CO2. The produced HCOOH yield over 10 wt % CIS@TCOF can be up to 171.2 µmol g-1 h-1 under visible light irradiation with good reproducibility, which is about 3 times as high as that over TCOF. Further in-depth studies indicate that the introduction of CIS not only enhances the visible light utilization but also restrains the recombination of photogenerated electron-hole pairs efficiently and facilitates the photoinduced charge transfer via the p-n heterojunction system due to the unique structural and compositional features. This research shows the great potential of COFs as efficient photocatalytic carbon fixation materials and provides a versatile route to construct semiconductor-COF heterostructures for photocatalysis.
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Ecological divergence due to habitat difference plays a prominent role in the formation of new species, but the genetic architecture during ecological speciation and the mechanism underlying phenotypic divergence remain less understood. Two wild ancestors of rice (Oryza rufipogon and Oryza nivara) are a progenitor-derivative species pair with ecological divergence and provide a unique system for studying ecological adaptation/speciation. Here, we constructed a high-resolution linkage map and conducted a quantitative trait locus (QTL) analysis of 19 phenotypic traits using an F2 population generated from a cross between the two Oryza species. We identified 113 QTLs associated with interspecific divergence of 16 quantitative traits, with effect sizes ranging from 1.61% to 34.1% in terms of the percentage of variation explained (PVE). The distribution of effect sizes of QTLs followed a negative exponential, suggesting that a few genes of large effect and many genes of small effect were responsible for the phenotypic divergence. We observed 18 clusters of QTLs (QTL hotspots) on 11 chromosomes, significantly more than that expected by chance, demonstrating the importance of coinheritance of loci/genes in ecological adaptation/speciation. Analysis of effect direction and v-test statistics revealed that interspecific differentiation of most traits was driven by divergent natural selection, supporting the argument that ecological adaptation/speciation would proceed rapidly under coordinated selection on multiple traits. Our findings provide new insights into the understanding of genetic architecture of ecological adaptation and speciation in plants and help effective manipulation of specific genes or gene cluster in rice breeding.
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Oryza , Oryza/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo , Locos de Características Quantitativas/genéticaRESUMO
BACKGROUND: It is uncertain whether adjunctive thrombolysis is beneficial for patients with ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) within 120 minutes of presentation. This study was to determine whether in patients presenting with ST-segment-elevation myocardial infarction a single bolus recombinant staphylokinase (r-SAK) before timely PCI leads to improved patency of the infarct-related artery and reduces the infarct size. METHODS: This is an open-label, prospective, multicenter, randomized study. We enrolled patients aged 18 to 75 years who were within 12 hours of symptom onset of ST-segment-elevation myocardial infarction and expected to undergo PCI within 120 minutes. Patients were administered loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive 5 mg bolus of r-SAK or normal saline intravenously before PCI. The primary end point was Thrombolysis in Myocardial Infarction flow grade 2 to 3 or grade 3 in the infarct-related artery 60 minutes after thrombolysis. The infarct size was detected by cardiac magnetic resonance 5 days after randomization. The safety end point was major bleeding (Bleeding Academic Research Consortium ≥3) during 30-day follow-up. RESULTS: A total of 283 patients were screened from 8 centers and 200 were randomized (median age, 58.5 years; 14% female). The median symptom to thrombolysis time was 252.5 (interquartile range, 142.8-423.8) minutes and thrombolysis to coronary arteriography was 50.0 (interquartile range, 37.0-66.0) minutes. Patients randomized to r-SAK compared with normal saline more often had Thrombolysis in Myocardial Infarction flow grade 2 to 3 (69.0% versus 29.0%; P<0.001) and Thrombolysis in Myocardial Infarction flow grade 3 (51.0% versus 18.0%; P<0.001) and had smaller infarct size (21.91±10.84% versus 26.85±12.37%; P=0.016). There was no increase in major bleeding (r-SAK, 1.0% versus control, 3.0%; P=0.616). CONCLUSIONS: A single bolus r-SAK before primary PCI for ST-segment-elevation myocardial infarction improves infarct-related artery patency and reduces infarct size without increasing major bleeding. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05023681.
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Metaloendopeptidases , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia/induzido quimicamente , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Solução Salina/uso terapêutico , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Resultado do Tratamento , Adolescente , Adulto Jovem , Adulto , IdosoRESUMO
OBJECTIVE: The present study aimed to investigate the accuracy of endoscopic ultrasonography (EUS) combined with Indian ink in locating target vessels of gastric varices (GVs) compared with conventional endoscopic techniques. Additionally, the characteristics of GVs under conventional endoscopy were also explored. METHODS: All 50 cirrhotic patients with GVs between August 2021 and December 2022 were included in the study. Firstly, conventional endoscopy was employed to identify GVs and to record the expected injection sites. Subsequently, EUS was used to locate the perforated vessel and the injection site was them marked with India ink followed by injection with cyanoacrylate (CYA). Finally, conventional endoscopy was used to examine GVs, to identify the marker points of Indian ink and to compare whether the injection points under conventional endoscopy were consistent with those marked with Indian ink. Furthermore, patients with consistent and inconsistent distribution of endoscopic markers and injection sites were divided into two groups. RESULTS: EUS could detect the perforating vessels in real time and intuitively. The distribution of markers using EUS was significantly different compared with the injection points obtained by conventional endoscopy (P < 0.001). Therefore, 20 cases were allocated to the consistent group and 30 cases to the non-consistent group. 16 patients who showed red wale signs were obtained in the consistent group and 11 patients in the non-consistent group (P = 0.048). The diameter of the largest GVs was 13.5 (10-15) mm in the consistent group compared with 10 (7.5-10) mm in the non-consistent group (P = 0.006). CONCLUSION: EUS could provide the exact location of GVs, thus more accurately describing the endoscopic characteristics of the GVs. Furthermore, the red wale signs and diameter of the largest GVs obtained using conventional endoscopy were helpful in determining the location of target GVs.
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Endossonografia , Varizes Esofágicas e Gástricas , Humanos , Endossonografia/métodos , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/etiologia , Tinta , Cianoacrilatos , Endoscopia Gastrointestinal , Hemorragia GastrointestinalRESUMO
[This corrects the article DOI: 10.1039/D3NA90045B.][This corrects the article DOI: 10.1039/D2NA00758D.].
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A photoinduced reductive Reformatsky reaction by cooperative dual-metal catalysis is described. This methodology enables the implementation of this venerable reaction in environmentally friendly conditions, obviating the need for a stoichiometric amount of metals. A broad range of synthetically useful ß-hydroxy esters can be efficiently prepared in moderate to high yields using this protocol.
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This study presents a general framework, namely, Sparse Spatiotemporal System Discovery (S3d), for discovering dynamical models given by Partial Differential Equations (PDEs) from spatiotemporal data. S3d is built on the recent development of sparse Bayesian learning, which enforces sparsity in the estimated PDEs. This approach enables a balance between model complexity and fitting error with theoretical guarantees. The proposed framework integrates Bayesian inference and a sparse priori distribution with the sparse regression method. It also introduces a principled iterative re-weighted algorithm to select dominant features in PDEs and solve for the sparse coefficients. We have demonstrated the discovery of the complex Ginzburg-Landau equation from a traveling-wave convection experiment, as well as several other PDEs, including the important cases of Navier-Stokes and sine-Gordon equations, from simulated data.
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A catalytic enantioselective polycyclization of tertiary enamides with terminal silyl enol ethers has been developed by virtue of Cu(OTf)2 catalysis with a novel spiropyrroline-derived oxazole (SPDO) ligand. This tandem reaction offers an effective approach to assemble bicyclic and tricyclic N-heterocycles bearing both aza- and oxa-quaternary stereogenic centers, which are primal subunits in a range of natural alkaloids. Strategic application of this methodology and a late-stage radical cyclization as key steps have been showcased in the concise total synthesis of (-)-cephalocyclidin A.
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An asymmetric [3+2] cycloaddition of quinone esters with 2,3-dihydrofuran has been realized via a newly developed Cu(II)/SPDO complex. It provides straightforward access to 2,3,3a,8a-tetrahydrofuro[2,3-b]benzofurans (TFB) with high enantioselectivity (up to 97.5:2.5 er) and diastereoselectivity (all >20:1 dr). The resulting adducts contain two adjacent stereocenters and a continuously functionalized benzene ring. Additionally, this transformation could be easily performed on a gram scale, allowing for expedient synthesis of natural dihydroaflatoxin D2 and aflatoxin B2.
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Ultrawide-bandgap semiconductors, possessing bandgaps distinctly larger than the 3.4 eV of GaN, have emerged as a promising class capable of achieving deep ultraviolet (UV) light detection. Based on first-principles calculations, we propose an unexplored two-dimensional (2D) InTeClO3 layered system with ultrawide bandgaps ranging from 4.34 eV of bulk to 4.54 eV of monolayer. Our calculations demonstrate that 2D InTeClO3 monolayer can be exfoliated from its bulk counterpart and maintain good thermal and dynamic stability at room temperature. The ultrawide bandgaps may be modulated by the small in-plane strains and layer thickness in a certain range. Furthermore, the 2D InTeClO3 monolayer shows promising electron transport behavior and strong optical absorption capacity in the deep UV range. A two-probe InTeClO3-based photodetection device has been constructed for evaluating the photocurrent. Remarkably, the effective photocurrent (5.7 A m-2 at photon energy of 4.2 eV) generation under polarized light has been observed in such a photodetector. Our results indicate that 2D InTeClO3 systems have strong photoresponse capacity in the deep UV region, accompanying the remarkable polarization sensitivity and high extinction ratio. These distinctive characteristics highlight the promising application prospects of InTeClO3 materials in the field of deep UV optoelectronics.
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An asymmetric conjugate addition of aldehydes with o-azaxylylene intermediates (indol-2-ones) from 3-bromooxindoles has been developed. The use of a novel spiro-pyrrolidine (SPD)-derived bifunctional N-sulfonylated amide catalyst is essential for a highly diastereo- and enantioselective transformation to provide a wide array of enantioenriched C3 quaternary oxindoles with structurally diverse ß-aldehyde appendages. Further application of this synthetic methodology enables the construction of the tricyclic cores of akuammiline-type alkaloids.
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BACKGROUND AND AIM: First, it has been demonstrated that endoscopic ultrasonography (EUS)-guided cyanoacrylate (CYA) injection (EUS-CYA) has greater efficacy than direct endoscopic injection of cyanoacrylate (DEI-CYA) for treating type 1-isolated gastric varices. However, it is necessary to conduct further studies to determine whether EUS has any advantage over the current guidelines for treating gastroesophageal varices type 1 (GOV1). Second, liver function is an important prognostic factor in patients with liver cirrhosis. Therefore, we evaluated the liver function of patients treated with EUS-CYA. METHODS: In a single-center study, a prospective cohort from February 2021 to September 2022 involving 89 patients with cirrhosis with GOV1 were assigned to undergo EUS-CYA (n = 45) or DEI-CYA (n = 44). The success rate of CYA injection, the rate of overall rebleeding, the rate of reintervention, the complications during the follow-up period, and the liver function were compared. RESULTS: In both groups, 100% of the operations were successful. The follow-up time of the two groups was 290 (153-398) days and 267 (177-416) days, respectively. In the EUS group, the perforating veins had an average diameter of 7.0 ± 2.7 mm, and they had a 100% occlusion rate. A statistically significant difference was found between the two groups regarding the number of sessions needed to eradicate GV (p = 0.005, pairwise comparisons were conducted using the Bonferroni correction method.), the late rebleeding rate after EUS-CYA [n = 3 (6.7%) vs n = 10 (22.7%); p = 0.032], and the incidence of postinjection ulcers [n = 4 (8.9%) vs n = 12 (27.3); p = 0.023)]. Following EUS or DEI-CYA treatment, the patient's liver function did not show any significant deterioration or decline. CONCLUSION: EUS-CYA has a higher eradication success rate and fewer complications, recurrences, and rebleeding episodes than DEI-CYA used for GOV1 treatment. In addition, EUS-CYA did not impair liver function.
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Varizes Esofágicas e Gástricas , Hemostase Endoscópica , Varizes , Humanos , Cianoacrilatos , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/terapia , Endossonografia/métodos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hemostase Endoscópica/métodos , Estudos Prospectivos , Resultado do Tratamento , Estudos Retrospectivos , Cirrose Hepática/complicações , Varizes/complicações , Varizes/terapia , RecidivaRESUMO
A nickel hydride-catalyzed regio- and enantioselective hydroalkylation reaction was developed to give access to a library of chiral ß- or γ-branched aromatic N-heterocycles. This intriguing asymmetric transformation features excellent selectivities, step- and atom-economies, and generating two kinds of chiral products through one synthetic strategy. Furthermore, the possible reaction mechanism was extensively investigated using numerous control experiments and density functional theory calculations.
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When calibrating a line-structured light vision system using a planar target, noise easily affects the solution of the coordinates of light stripe points at the camera coordinate frame. Therefore, the planar target must be placed in the measurement space many times to capture more target images for improving calibration stability and achieving relatively high calibration accuracy. This complicates the calibration process. This paper proposes a calibration method considering the measurement baselines of a planar target. The planar target is placed only two times, and two target images are captured correspondingly. A three-point subset is made up of the two calibration points that form the measurement baseline with the longest 2D projection and any other calibration point. In this way, it is less affected by noise when using the three-point subsets to establish the equations. Then, we use the lengths of the measurement baselines provided by all three-point subsets and their 2D projections to solve the coordinates of light stripe points at the camera coordinate frame more accurately to calibrate the line-structured light vision system. Both the simulation and actual experiment results demonstrate the feasibility of our method. Based on our calibration method, the RMS error is 0.035 mm for length measurement and 0.054 mm for height measurement. Compared with other existing methods, our method needs only two target images. It can also achieve more accurate calibration results than the other methods. In addition, our calibration method increases the applicability of the line-structured light measurement method by reducing the number of target swings.
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The origin of domesticated Asian rice (Oryza sativa L.) has been controversial for more than half a century. The debates have focused on two leading hypotheses: a single domestication event in China or multiple domestication events in geographically separate areas. These two hypotheses differ in their predicted history of genes/alleles selected during domestication. Here we amassed a dataset of 1,578 resequenced genomes, including an expanded sample of wild rice from throughout its geographic range. We identified 993 selected genes that generated phylogenetic trees on which japonica and indica formed a monophyletic group, suggesting that the domestication alleles of these genes originated only once in either japonica or indica. Importantly, the domestication alleles of most selected genes (~80%) stemmed from wild rice in China, but the domestication alleles of a substantial minority of selected genes (~20%) originated from wild rice in South and Southeast Asia, demonstrating separate domestication events of Asian rice.