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Accurate automated extraction of brain vessel centerlines from CTA images plays an important role in diagnosis and therapy of cerebrovascular diseases, such as stroke. However, this task remains challenging due to the complex cerebrovascular structure, the varying imaging quality, and vessel pathology effects. In this paper, we consider automatic lumen segmentation generation without additional annotation effort by physicians and more effective use of the generated lumen segmentation for improved centerline extraction performance. We propose an automated framework for brain vessel centerline extraction from CTA images. The framework consists of four major components: (1) pre-processing approaches that register CTA images with a CT atlas and divide these images into input patches, (2) lumen segmentation generation from annotated vessel centerlines using graph cuts and robust kernel regression, (3) a dual-branch topology-aware UNet (DTUNet) that can effectively utilize the annotated vessel centerlines and the generated lumen segmentation through a topology-aware loss (TAL) and its dual-branch design, and (4) post-processing approaches that skeletonize the predicted lumen segmentation. Extensive experiments on a multi-center dataset demonstrate that the proposed framework outperforms state-of-the-art methods in terms of average symmetric centerline distance (ASCD) and overlap (OV). Subgroup analyses further suggest that the proposed framework holds promise in clinical applications for stroke treatment. Code is publicly available at https://github.com/Liusj-gh/DTUNet.

Identification and detection of thin-cap fibroatheroma (TCFA) from intravascular optical coherence tomography (IVOCT) images is critical for treatment of coronary heart diseases. Recently, deep learning methods have shown promising successes in TCFA identification. However, most methods usually do not effectively utilize multi-view information or incorporate prior domain knowledge. In this paper, we propose a multi-view contour-constrained transformer network (MVCTN) for TCFA identification in IVOCT images. Inspired by the diagnosis process of cardiologists, we use contour constrained self-attention modules (CCSM) to emphasize features corresponding to salient regions (i.e., vessel walls) in an unsupervised manner and enhance the visual interpretability based on class activation mapping (CAM). Moreover, we exploit transformer modules (TM) to build global-range relations between two views (i.e., polar and Cartesian views) to effectively fuse features at multiple feature scales. Experimental results on a semi-public dataset and an in-house dataset demonstrate that the proposed MVCTN outperforms other single-view and multi-view methods. Lastly, the proposed MVCTN can also provide meaningful visualization for cardiologists via CAM.

Transformer is beneficial for image denoising tasks since it can model long-range dependencies to overcome the limitations presented by inductive convolutional biases. However, directly applying the transformer structure to remove noise is challenging because its complexity grows quadratically with the spatial resolution. In this paper, we propose an efficient Dual-branch Deformable Transformer (DDT) denoising network which captures both local and global interactions in parallel. We divide features with a fixed patch size and a fixed number of patches in local and global branches, respectively. In addition, we apply deformable attention operation in both branches, which helps the network focus on more important regions and further reduces computational complexity. We conduct extensive experiments on real-world and synthetic denoising tasks, and the proposed DDT achieves state-of-the-art performance with significantly fewer computational costs., Comment: The code is avaliable at: https://github.com/Merenguelkl/DDT

Identification and detection of thin-cap fibroatheroma (TCFA) from intravascular optical coherence tomography (IVOCT) images is critical for treatment of coronary heart diseases. Recently, deep learning methods have shown promising successes in TCFA identification. However, most methods usually do not effectively utilize multi-view information or incorporate prior domain knowledge. In this paper, we propose a multi-view contour-constrained transformer network (MVCTN) for TCFA identification in IVOCT images. Inspired by the diagnosis process of cardiologists, we use contour constrained self-attention modules (CCSM) to emphasize features corresponding to salient regions (i.e., vessel walls) in an unsupervised manner and enhance the visual interpretability based on class activation mapping (CAM). Moreover, we exploit transformer modules (TM) to build global-range relations between two views (i.e., polar and Cartesian views) to effectively fuse features at multiple feature scales. Experimental results on a semi-public dataset and an in-house dataset demonstrate that the proposed MVCTN outperforms other single-view and multi-view methods. Lastly, the proposed MVCTN can also provide meaningful visualization for cardiologists via CAM., ImPhys/Vos group, ImPhys/Computational Imaging

The classic or deterministic understanding of thermal comfort contends that it is driven exclusively by the physics of the body’s heat exchange with its immediate thermal environment. But in recent decades there has been widespread recognition that a person’s thermal history and adaptation level, including behavioral, physiological and psychological processes operating on various timescales, also influence whether indoor climatic conditions will be deemed comfortable and acceptable, or not, as the case may be. This contextual view of the comfort construct is referred to as the adaptive model, and its empirical basis is an extensive body of field studies conducted in diverse occupancy and building types located across a broad cross-section of the world’s climate zones. The basic research design of the comfort field study consists of paired observations of objective indoor climatic parameters and their subjective evaluation by building occupants using comfort rating scales. The first global adaptive comfort standard, ratified by ASHRAE in 2004, was based on a statistical analysis of approximately 21,000 complete sets of objective indoor climatic observations and their “right-here-right-now” subjective evaluations by the building occupants who were exposed to them. Over a decade has elapsed since ASHRAE Standard 55-2004 was published and since then there has been an escalation in adaptive comfort field research activity around the world. Recently ASHRAE’s thermal comfort technical committee (TC 2.1), in collaboration with the International Energy Agency (Annex 69), have taken on the challenge of systematically collating and harmonizing the raw data collected in recent comfort field studies from around the world into an expanded, quality-assured database. When the project is completed this public-domain resource will underpin myriad inquiries by the thermal comfort community, researchers and practitioners alike. The aim of this presentation is to describe the DB-II proj

The classic or deterministic understanding of thermal comfort contends that it is driven exclusively by the physics of the body’s heat exchange with its immediate thermal environment. But in recent decades there has been widespread recognition that a person’s thermal history and adaptation level, including behavioral, physiological and psychological processes operating on various timescales, also influence whether indoor climatic conditions will be deemed comfortable and acceptable, or not, as the case may be. This contextual view of the comfort construct is referred to as the adaptive model, and its empirical basis is an extensive body of field studies conducted in diverse occupancy and building types located across a broad cross-section of the world’s climate zones. The basic research design of the comfort field study consists of paired observations of objective indoor climatic parameters and their subjective evaluation by building occupants using comfort rating scales. The first global adaptive comfort standard, ratified by ASHRAE in 2004, was based on a statistical analysis of approximately 21,000 complete sets of objective indoor climatic observations and their “right-here-right-now” subjective evaluations by the building occupants who were exposed to them. Over a decade has elapsed since ASHRAE Standard 55-2004 was published and since then there has been an escalation in adaptive comfort field research activity around the world. Recently ASHRAE’s thermal comfort technical committee (TC 2.1), in collaboration with the International Energy Agency (Annex 69), have taken on the challenge of systematically collating and harmonizing the raw data collected in recent comfort field studies from around the world into an expanded, quality-assured database. When the project is completed this public-domain resource will underpin myriad inquiries by the thermal comfort community, researchers and practitioners alike. The aim of this presentation is to describe the DB-II proj

A series of 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives 7a-i were synthesized and evaluated as novel acetylcholinesterase (AChE) inhibitors. All target compounds were evaluated in vitro for the inhibitory activities against AChE via Ellman colorimetric assay. Compound 7c showed an excellent (89.82%) inhibitory activity. The molecular docking studies revealed that 7c, 7d and 7g, with the lateral chain in the para position of the phenyl ring, possessed an optimal docking pose and can perfectly fit into the catalytic active site (CAS) and peripheral anionic site (PAS), simultaneously, and, consequently, exhibited higher inhibitory potency than 7b that bears the same lateral chain as 7g, but in the ortho position of the phenyl ring. © 2014 Elsevier Masson SAS. All rights reserved.

A series of 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives 7a-i were synthesized and evaluated as novel acetylcholinesterase (AChE) inhibitors. All target compounds were evaluated in vitro for the inhibitory activities against AChE via Ellman colorimetric assay. Compound 7c showed an excellent (89.82%) inhibitory activity. The molecular docking studies revealed that 7c, 7d and 7g, with the lateral chain in the para position of the phenyl ring, possessed an optimal docking pose and can perfectly fit into the catalytic active site (CAS) and peripheral anionic site (PAS), simultaneously, and, consequently, exhibited higher inhibitory potency than 7b that bears the same lateral chain as 7g, but in the ortho position of the phenyl ring. © 2014 Elsevier Masson SAS. All rights reserved.

A series of 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives 7a-i were synthesized and evaluated as novel acetylcholinesterase (AChE) inhibitors. All target compounds were evaluated in vitro for the inhibitory activities against AChE via Ellman colorimetric assay. Compound 7c showed an excellent (89.82%) inhibitory activity. The molecular docking studies revealed that 7c, 7d and 7g, with the lateral chain in the para position of the phenyl ring, possessed an optimal docking pose and can perfectly fit into the catalytic active site (CAS) and peripheral anionic site (PAS), simultaneously, and, consequently, exhibited higher inhibitory potency than 7b that bears the same lateral chain as 7g, but in the ortho position of the phenyl ring. © 2014 Elsevier Masson SAS. All rights reserved.

Objective: To design and synthesize nine 6-arylmethyl-3-(4-alkoxyphenyl)-7H-thiazolo[3, 2-b]-1,2,4-triazin-7-one derivatives based on our previous work and molecular modeling, and to determine the acetylcholinesterase (AChE) inhibitory activity, the structure-activity relationship and the influences of group types on C6 arylmethyl and the side chain containing nitrogen at C3 phenyl on the 7H-thiazolo[3, 2-b]-1, 2, 4-triazin-7-one scaffold. Methods: Benzaldehyde or substituted benzaldehyde was reacted with N-acetoglycine by using Erlenmeyer-Plöchl reaction, hydrolyzation reaction and condensation reaction to obtain 6-arylmethyl-3-(4-hydroxyphenyl)-7H-thiazolo[3, 2-b]-1,2,4-triazin-7-one derivatives. Then the derivatives were transferred to nine target compounds 6-arylmethyl-3-(4-alkoxyphenyl)-7H-thiazolo[3, 2-b]-1,2,4-triazin-7-one derivatives by using Williamson reaction. AChE inhibitory activity was determined by the Ellman colorimetric assay with huperzine-A as the positive control. Results: The structures of all of the target compounds were characterized by mass spectra, infrared spectra and proton NMR. All of the target compounds exhibited inhibitory activities against human AChE in vitro, eight of them exhibited more than 40% inhibition at 10 μmol·L-1. Conclusion: 6-Arylmethyl-3-(4-alkoxyphenyl)-7H-thiazolo[3, 2-b]-1,2,4-triazin-7-one derivatives would be a kind of highly active AChE inhibitors. The inhibitory activities of target compounds with electron-donating group are more powerful than those of target compounds with electron-withdrawing group at C6 arylmethyl on the 7H-thiazolo[3, 2-b]-1, 2, 4-triazin-7-one scaffold.

Acetylcholinesterase (AChE) inhibitors play an important role in the treatment of Alzheimer's disease. To study the effect of the presence of a fluoro group on inhibitory activity against AChE, a series of 3-aryl-6-(4-fluorobenzyl)-7H-thiazolo[3,2]-1,2,4-triazin-7-one derivatives have been synthesized, in which a hydrogen atom has been substituted by a fluorine in the aromatic nucleus of 6-arylmethyl-3-phenyl-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives, a series of compounds previously reported by us to have inhibitory activity against acetylcholinesterase. From the molecular docking studies, it was found that, in general, a key hydrogen bond of target compounds to the OH of Tyr341 and a close contact with relevant residues in the catalytic site are prerequisites for high inhibitory activity.

Acetylcholinesterase (AChE) inhibitors play an important role in the treatment of Alzheimer's disease. To study the effect of the presence of a fluoro group on inhibitory activity against AChE, a series of 3-aryl-6-(4-fluorobenzyl)-7H-thiazolo[3,2]-1,2,4-triazin-7-one derivatives have been synthesized, in which a hydrogen atom has been substituted by a fluorine in the aromatic nucleus of 6-arylmethyl-3-phenyl-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives, a series of compounds previously reported by us to have inhibitory activity against acetylcholinesterase. From the molecular docking studies, it was found that, in general, a key hydrogen bond of target compounds to the OH of Tyr341 and a close contact with relevant residues in the catalytic site are prerequisites for high inhibitory activity.

Acetylcholinesterase (AChE) inhibitors play an important role in the treatment of Alzheimer's disease. To study the effect of the presence of a fluoro group on inhibitory activity against AChE, a series of 3-aryl-6-(4-fluorobenzyl)-7H-thiazolo[3,2]-1,2,4-triazin-7-one derivatives have been synthesized, in which a hydrogen atom has been substituted by a fluorine in the aromatic nucleus of 6-arylmethyl-3-phenyl-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives, a series of compounds previously reported by us to have inhibitory activity against acetylcholinesterase. From the molecular docking studies, it was found that, in general, a key hydrogen bond of target compounds to the OH of Tyr341 and a close contact with relevant residues in the catalytic site are prerequisites for high inhibitory activity.

Alzhemier's disease (AD) is a common form of dementia in the ageing population which is characterized by depositions of amyloids and a cholinergic neurotransmission deficit in the brain. Current therapeutic intervention for AD is primarily based on the inhibition of brain acetylcholinesterase (AChE) to restore the brain acetylcholine level. Cryptotanshinone (CT) and dihydrotanshinone (DT) were diterpenoids extracted from Salvia miltiorrhiza Bge. having anti-cholinesterase activity. Here we characterized the inhibition property of these two diterpenoids towards human AChE and butyrylcholinesterase (BChE). Both CT and DT were found to be mixed non-competitive inhibitors for human AChE and an uncompetitive inhibitor for human BChE. The docking analyses of CT and DT into the active sites of both cholinesterases indicate that they interact with the allosteric site inside the active-site gorge mainly by hydrophobic interactions. © 2010 Elsevier Ireland Ltd.

Alzhemier's disease (AD) is a common form of dementia in the ageing population which is characterized by depositions of amyloids and a cholinergic neurotransmission deficit in the brain. Current therapeutic intervention for AD is primarily based on the inhibition of brain acetylcholinesterase (AChE) to restore the brain acetylcholine level. Cryptotanshinone (CT) and dihydrotanshinone (DT) were diterpenoids extracted from Salvia miltiorrhiza Bge. having anti-cholinesterase activity. Here we characterized the inhibition property of these two diterpenoids towards human AChE and butyrylcholinesterase (BChE). Both CT and DT were found to be mixed non-competitive inhibitors for human AChE and an uncompetitive inhibitor for human BChE. The docking analyses of CT and DT into the active sites of both cholinesterases indicate that they interact with the allosteric site inside the active-site gorge mainly by hydrophobic interactions. © 2010 Elsevier Ireland Ltd.

Alzhemier's disease (AD) is a common form of dementia in the ageing population which is characterized by depositions of amyloids and a cholinergic neurotransmission deficit in the brain. Current therapeutic intervention for AD is primarily based on the inhibition of brain acetylcholinesterase (AChE) to restore the brain acetylcholine level. Cryptotanshinone (CT) and dihydrotanshinone (DT) were diterpenoids extracted from Salvia miltiorrhiza Bge. having anti-cholinesterase activity. Here we characterized the inhibition property of these two diterpenoids towards human AChE and butyrylcholinesterase (BChE). Both CT and DT were found to be mixed non-competitive inhibitors for human AChE and an uncompetitive inhibitor for human BChE. The docking analyses of CT and DT into the active sites of both cholinesterases indicate that they interact with the allosteric site inside the active-site gorge mainly by hydrophobic interactions. © 2010 Elsevier Ireland Ltd.