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1.
Mol Biol Evol ; 41(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38768215

RESUMO

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.


Assuntos
Genoma de Planta , Seleção Genética , Adaptação Fisiológica/genética , Altitude
2.
J Am Chem Soc ; 146(37): 25445-25450, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39235150

RESUMO

To date, it remains challenging to precisely and efficiently construct structurally intriguing polycarbocycles with densely packed stereocenters in organic synthesis. Niduterpenoid B, a naturally occurring ERα inhibitor, exemplifies this complexity with its intricate polycyclic network comprising 5 cyclopentane and 1 cyclopropane rings, featuring 13 contiguous stereocenters, including 4 all-carbon quaternary centers. In this work, we describe the first total synthesis of niduterpenoid B using a structural reorganization strategy. Key features include the following: (1) an efficient methoxy-controlled cascade reaction that precisely forges a highly functionalized tetraquinane (A-D rings) bearing sterically hindered contiguous quaternary stereocenters; (2) a rhodium-catalyzed [1 + 2] cycloaddition that facilitates the construction of a strained 3/5 bicycle (E-F rings) angularly fused with ring D.

3.
Mol Ecol ; 33(5): e17268, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38230514

RESUMO

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.


Assuntos
Oryza , Oryza/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo , Locos de Características Quantitativas/genética
4.
Chemistry ; : e202402757, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242340

RESUMO

The direct hydrogenation of 2-nitroacylbenzene to 2,1-benzisoxazole presents a significant challenge in the pharmaceutical and fine chemicals industries. In this study, a defect engineering strategy is employed to create bifunctional single-atom catalysts (SACs) by anchoring Pt single atoms onto metal vacancies within MgO(Al) nanosheets. The resultant Pt1/MgO(Al) SAC displays an exceptional catalytic activity and selectivity in the hydrogenation-cyclization of 2-nitroacylbenzene, achieving a 97.5% yield at complete conversion and a record-breaking turnover frequency of 458.8 h-1 under the mild conditions. The synergistic catalysis between the fully exposed single-atom Pt sites within a unique Pt-O-Mg/Al moiety and the abundant basic sites of the MgO(Al) support is responsible for this outstanding catalytic performance. The current work, therefore, paves the way for developing bifunctional or multifunctional SACs that can enhance efficient organocatalytic conversions.

5.
J Org Chem ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291865

RESUMO

Based on rich sulfur-involving chemical transformations, a novel spokewise synthetic strategy, a subclass of the collective strategies, has been developed to concisely synthesize four erythrina alkaloids through a single-step transformation from a common synthetic precursor. Moreover, six additional erythrina alkaloids have also been synthesized by subsequent 1-2 steps chemical transformations. The current synthetic approaches provide a valuable platform for collective total syntheses of erythrina alkaloids and pseudo-natural erythrina alkaloids.

6.
Surg Endosc ; 38(2): 633-639, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012437

RESUMO

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.


Assuntos
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 Gastrointestinal
7.
Dig Endosc ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39253829

RESUMO

OBJECTIVES: Although the incidence of isolated gastric varices type 1 (IGV1) bleeding is low, the condition is highly dangerous and associated with high mortality, making its treatment challenging. We aimed to compare the safety and efficacy of endoscopic clipping combined with cyanoacrylate injection (EC-CYA) vs. transjugular intrahepatic portosystemic shunt (TIPS) in treating IGV1. METHODS: In a single-center, randomized controlled trial, patients with IGV1 bleeding were randomly assigned to the EC-CYA group or TIPS group. The primary end-points were gastric variceal rebleeding rates and technical success. Secondary end-points included cumulative nonbleeding rates, mortality, and complications. RESULTS: A total of 156 patients between January 2019 and April 2023 were selected and randomly assigned to the EC-CYA group (n = 76) and TIPS group (n = 80). The technical success rate was 100% for both groups. The rebleeding rates were 14.5% in the EC-CYA group and 8.8% in the TIPS group, showing no significant difference (P = 0.263). Kaplan-Meier analysis revealed that the cumulative nonbleeding rates at 6, 12, 24, and 36 months for the two groups lacked statistical significance (P = 0.344). Similarly, cumulative survival rates at 12, 24, and 36 months for the two groups were not statistically significant (P = 0.916). The bleeding rates from other causes were 13.2% and 6.3% for the respective groups, showing no significant difference (P = 0.144). No instances of ectopic embolism were observed in either group. The incidence of hepatic encephalopathy (HE) in the TIPS group was statistically higher than that in the EC-CYA group (P = 0.001). CONCLUSION: Both groups are effective in controlling IGV1 bleeding. Notably, EC-CYA did not result in ectopic embolism, and the incidence of HE was lower than that observed with TIPS.

8.
Angew Chem Int Ed Engl ; : e202412337, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106111

RESUMO

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.

9.
J Am Chem Soc ; 145(40): 22122-22134, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37749771

RESUMO

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.

10.
J Am Chem Soc ; 145(49): 26550-26556, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38019148

RESUMO

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.

11.
Am Heart J ; 265: 31-39, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37369268

RESUMO

BACKGROUND: Time to reperfusion is the key to the treatment of patients with ST-elevation myocardial infarction (STEMI). It is uncertain whether adjunctive thrombolytic therapy combined with contemporary antiplatelet agent ticagrelor improves outcomes as administered prior to primary percutaneous coronary intervention (PCI) expected to be performed within 120 minutes. METHODS: OPTIMA-6 is a multicenter, randomized, double-blind, placebo-controlled, and superiority trial to evaluate the efficacy of a bolus of half-dose recombinant staphylokinase (r-SAK) vs placebo prior to timely primary PCI in patients with STEMI. Enrollment began in April 2023 and is expected to enroll 2,260 patients at approximately 50 centers. Patients with acute STEMI presenting ≤12 hours of symptom onset and expected to undergo primary PCI within 120 minutes but more than 30 minutes are to be randomized to a bolus of half-dose r-SAK or placebo. All recruited patients will be mandatory to take aspirin and ticagrelor and receive a bolus of loading dose heparin before the thrombolytic therapy. The primary efficacy endpoint is major adverse cardiovascular events (MACE) within 90 days, and the MACE is defined as a composite of all-cause death, reinfarction, unplanned target vessel revascularization, heart failure or cardiogenic shock, and major ventricular arrhythmia. The primary safety endpoints are major bleeding events (BARC 3, 5) within 90 days. CONCLUSIONS: OPTIMA-6 will reveal the efficacy and safety of a contemporary facilitated PCI with a bolus of half-dose r-SAK in combination with ticagrelor in patients with STEMI.

12.
Opt Express ; 31(6): 9872-9885, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157548

RESUMO

Compressive sensing makes it possible to explore two-dimensional spatial information using a single-point detector. However, the reconstruction of the three-dimensional (3D) morphology using a single-point sensor is largely limited by the calibration. Here we demonstrate a pseudo-single-pixel camera calibration (PSPC) method using pseudo phase matching in stereo, which can perform 3D calibration of low-resolution images with the help of a high-resolution digital micromirror device (DMD) in the system. In this paper, we use a high-resolution CMOS to pre-image the DMD surface and successfully calibrate the spatial position of a single-point detector and the projector with the support of binocular stereo matching. Our system achieved sub-millimeter reconstructions of spheres, steps, and plaster portraits at low compression ratios with a high-speed digital light projector (DLP) and a highly sensitive single-point detector.

13.
Opt Lett ; 48(8): 2034-2037, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37058635

RESUMO

There is an increasing demand for high-precision gas absorption spectroscopy in basic research and industrial applications, such as gas tracking and leak warning. In this Letter, a novel, to the best of our knowledge, high-precision and real-time gas detection method is proposed. A femtosecond optical frequency comb is used as the light source, and a broadening pulse containing a range of oscillation frequencies is formed after passing through a dispersive element and a Mach-Zehnder interferometer. Four absorption lines of H13C14N gas cells are measured at five different concentrations within a single pulse period. A single scan detection time of only 5 ns is obtained along with a coherence averaging accuracy of 0.0055 nm. High-precision and ultrafast detection of the gas absorption spectrum is accomplished while overcoming complexities related to the acquisition system and light source that are encountered in existing methods.

14.
J Org Chem ; 88(6): 3954-3964, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36881939

RESUMO

A novel tandem oxidative Ritter reaction/hydration/aldol condensation of α-arylketones with substituted propiolonitriles has been developed. This protocol conveniently affords a wide range of functionalized 3-acyl-3-pyrrolin-2-ones through the efficient construction of four chemical bonds, a C-N bond, a C═C bond, and two C═O bonds, and the formation of one ring bearing an aza-quaternary center, which is ascribed to the strategical introduction of functionalized nitriles to this transformation. A reaction mechanism was proposed based on some control experiments.

15.
J Org Chem ; 88(20): 14670-14675, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37815481

RESUMO

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.

16.
Phys Chem Chem Phys ; 25(8): 6112-6120, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752084

RESUMO

One-dimensional nanowires have emerged as compelling ideal materials due to their characteristic structure, properties, and applications in nanodevices. Herein, based on experimental vdW-chain bulk crystals, a series of one-dimensional (1D) XVYVIZVII (X = As, Sb, Bi; Y = S, Se, Te; Z = Cl, Br, I) ternary nanowires are theoretically investigated. Such exfoliated 1D nanowires possess excellent stability and moderate band gaps (1.76-3.16 eV). The calculated electron mobilities were found to reach a magnitude of 102 cm2 V-1 s-1 and even up to 322.95 cm2 V-1 s-1 for 1D BiSeI nanowires, which are much larger than those of the previously reported 1D materials. Furthermore, the appropriate band edge alignments and considerable optical absorption endow 1D XVYVIZVII nanowires with prospective photocatalytic properties for water splitting. Notably, AsSI and AsSeI nanowires possess a unique non-centrosymmetric structure and exhibit promising 1D ferroelectricity. Large spontaneous polarization values, Ps, of 11.31 × 10-10 and 6.92 × 10-10 C m-1 are obtained for 1D AsSI and AsSeI nanowires, respectively, and such 1D ferroelectricity can be regulated by intra-chain strains. Our calculations not only broaden the family of 1D materials but also reveal their great potential applications in electronic, optoelectronic, and ferroelectric devices.

17.
Phys Chem Chem Phys ; 25(42): 29241-29248, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37874031

RESUMO

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.

18.
Surg Endosc ; 37(11): 8277-8284, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37674054

RESUMO

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.


Assuntos
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 , Recidiva
19.
J Opt Soc Am A Opt Image Sci Vis ; 40(7): 1397-1408, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706741

RESUMO

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.

20.
Chaos ; 33(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37967264

RESUMO

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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