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1.
IEEE Trans Vis Comput Graph ; 29(4): 1977-1991, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34941511

RESUMO

Maintaining global consistency continues to be critical for online 3D indoor scene reconstruction. However, it is still challenging to generate satisfactory 3D reconstruction in terms of global consistency for previous approaches using purely geometric analysis, even with bundle adjustment or loop closure techniques. In this article, we propose a novel real-time 3D reconstruction approach which effectively integrates both semantic and geometric cues. The key challenge is how to map this indicative information, i.e., semantic priors, into a metric space as measurable information, thus enabling more accurate semantic fusion leveraging both the geometric and semantic cues. To this end, we introduce a semantic space with a continuous metric function measuring the distance between discrete semantic observations. Within the semantic space, we present an accurate frame-to-model semantic tracker for camera pose estimation, and semantic pose graph equipped with semantic links between submaps for globally consistent 3D scene reconstruction. With extensive evaluation on public synthetic and real-world 3D indoor scene RGB-D datasets, we show that our approach outperforms the previous approaches for 3D scene reconstruction both quantitatively and qualitatively, especially in terms of global consistency.

2.
Pest Manag Sci ; 78(5): 2011-2021, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35118797

RESUMO

BACKGROUND: Insect pests seriously decrease the yield and quality of agricultural crops. Resistance to commonly used insecticides is increasingly undermining their effectiveness, and therefore the development of agents with novel modes of action is desirable. Isoxazolines are a new class of insecticides that act on γ-aminobutyric acid (GABA) gated chloride channels. In this work, we used the highly active 4-triazolyphenyl isoxazoline DP-9 as a parent structure to design and synthesize a series of quaternary ammonium salt (QAS) derivatives, and we systematically evaluated their insecticidal and antifungal activities. RESULTS: Many of the synthesized QASs exhibit insecticidal activities equivalent to or higher than that of DP-9. In particular, compounds I-31 (93%, 0.00005 mg/L) and I-34 (80%, 0.00001 mg/L) showed insecticidal activities against diamondback moth larvae that were 2-10 times higher than those of fluralaner (70%, 0.0001 mg/L) and DP-9 (80%, 0.0001 mg/L), in addition to showing excellent activities against oriental armyworm, fall armyworm, cotton bollworm, corn borer, and mosquito larvae. Furthermore, all of the synthesized compounds also showed broad-spectrum fungicidal activities. CONCLUSION: The insecticidal activities of QAS derivatives of DP-9 were the same as or better than the activity of DP-9. Compounds I-31 and I-34 showed better insecticidal activities against diamondback moth larvae than fluralaner and DP-9, and thus are promising new candidates for insecticide research.


Assuntos
Compostos de Amônio , Inseticidas , Mariposas , Animais , Desenho de Fármacos , Inseticidas/química , Larva , Estrutura Molecular , Relação Estrutura-Atividade
3.
IEEE Trans Vis Comput Graph ; 28(4): 1745-1757, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33001804

RESUMO

Accurate camera pose estimation is essential and challenging for real world dynamic 3D reconstruction and augmented reality applications. In this article, we present a novel RGB-D SLAM approach for accurate camera pose tracking in dynamic environments. Previous methods detect dynamic components only across a short time-span of consecutive frames. Instead, we provide a more accurate dynamic 3D landmark detection method, followed by the use of long-term consistency via conditional random fields, which leverages long-term observations from multiple frames. Specifically, we first introduce an efficient initial camera pose estimation method based on distinguishing dynamic from static points using graph-cut RANSAC. These static/dynamic labels are used as priors for the unary potential in the conditional random fields, which further improves the accuracy of dynamic 3D landmark detection. Evaluation using the TUM and Bonn RGB-D dynamic datasets shows that our approach significantly outperforms state-of-the-art methods, providing much more accurate camera trajectory estimation in a variety of highly dynamic environments. We also show that dynamic 3D reconstruction can benefit from the camera poses estimated by our RGB-D SLAM approach.

4.
J Org Chem ; 85(15): 10271-10282, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32664730

RESUMO

Herein, we describe a method for the synthesis of aryl-(het)aryl ketones by Rh(III)-catalyzed direct coupling between quinoline-8-carbaldehydes and (het)arylboronic acids. The method has a broad substrate scope, a high functional group tolerance, and uses commercially available starting materials. Scale-up of the reaction and subsequent synthesis of tubulin polymerization inhibitor demonstrated its utilities. A plausible mechanism was proposed on the basis of the fact that a stable cycloacylrhodium intermediate complex could be used as catalyst, and the complex reacted stoichiometrically with (het)arylboronic acids.


Assuntos
Quinolinas , Ródio , Ácidos Borônicos , Catálise , Cetonas
5.
Pest Manag Sci ; 76(10): 3369-3376, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31756256

RESUMO

BACKGROUND: Food is an important strategic material related to national economy and people's livelihood. Plant diseases seriously affect crop yield and quality. Marine natural products are an important source for novel drugs discovery. In this work, meridianin alkaloids were selected as the parent structure. A series of meridianin alkaloid analogues were rationally designed, synthesized and evaluated for their antiviral activities and fungicidal activities. RESULT: These compounds were found to have good antiviral and fungicidal activities for the first time. The structure-activity relationship (SAR) research revealed that introducing bromine atom at the 5-position of indole ring is beneficial to antiviral activity, but introducing methoxy group is not conducive. Introducing bromine atom at the 6-position of indole ring or nitrogen atom at the 7-position of the indole ring resulted in lower antiviral activity. Most of the meridianin derivatives showed higher anti-TMV activities at 500 µg mL-1 than Ribavirin, especially for compounds 6c, 8a and 10a. All of the compounds also displayed broad spectrum fungicidal activities against 14 kinds of phytopathogenic fungi at 50 µg mL-1 . CONCLUSION: Compound 6c with relatively simple structure and excellent antiviral activity, which is similar to that of Ningnanmycin, emerged as novel anti-TMV lead compound. Compound 5d with broad spectrum and high effect fungicidal activity emerged as a new fungicidal lead compound. Current research lays a solid foundation for the application of meridianin alkaloids in crop protection. © 2019 Society of Chemical Industry.


Assuntos
Antivirais/farmacologia , Alcaloides , Produtos Biológicos , Desinfetantes , Desenho de Fármacos , Fungos , Estrutura Molecular , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco
6.
Org Lett ; 21(14): 5728-5732, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31251074

RESUMO

Herein we report a protocol for visible-light-induced copper-catalyzed decarboxylative coupling reactions between N-heteroarenes and redox-active esters. Various N-hydroxyphthalimide esters reacted with isoquinoline, quinoline, pyridine, pyrimidine, quinazoline, phthalazine, phenanthridine, and pyridazine to give the corresponding products in modest to excellent yields. The reactions proceed under mild conditions and have a broad scope and high functional group tolerance. Mechanistic studies revealed that the catalytic behavior of CuI photocatalyst generated in situ was consistent with that of preformed [Cu(dmp)(xantphos)]BF4.

7.
RSC Adv ; 9(62): 36213-36216, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35540617

RESUMO

Herein, we report an organo-photoredox-based protocol using 2,2-diethoxyacetic acid as the acetal source to achieve acetalation of alkynyl bromides to afford various alkynyl acetal products. In addition to arylethynyl bromides, substrates bearing heteroaryl rings (thiophene, pyridine, and indole) smoothly gave the corresponding acetalation products. This mild protocol has potential utility for the synthesis of aldehydes by further protonization.

8.
IEEE Trans Vis Comput Graph ; 22(8): 2024-36, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26336128

RESUMO

In this work we explore a support-induced structural organization of object parts. We introduce the concept of support substructures, which are special subsets of object parts with support and stability. A bottom-up approach is proposed to identify such substructures in a support relation graph. We apply the derived high-level substructures to part-based shape reshuffling between models, resulting in nontrivial functionally plausible model variations that are difficult to achieve with symmetry-induced substructures by the state-of-the-art methods. We also show how to automatically or interactively turn a single input model to new functionally plausible shapes by structure rearrangement and synthesis, enabled by support substructures. To the best of our knowledge no single existing method has been designed for all these applications.

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