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1.
Int J Surg ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38759695

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are found in primary and advanced tumours. They are primarily involved in tumour progression through complex mechanisms with other types of cells in the tumour microenvironment. However, essential fibroblasts-related genes (FRG) in bladder cancer still need to be explored, and there is a shortage of an ideal predictive model or molecular subtype for the progression and immune therapeutic assessment for bladder cancer, especially muscular-invasive bladder cancer based on the FRG. MATERIALS AND METHODS: CAF-related genes of bladder cancer were identified by analyzing single-cell RNA sequence datasets, and bulk transcriptome datasets and gene signatures were used to characterize them. Then, ten types of machine learning algorithms were utilized to determine the hallmark FRG and construct the FRG index (FRGI) and subtypes. Further molecular subtypes combined with CD8+ T-cells were established to predict the prognosis and immune therapy response. RESULTS: 54 BLCA-related FRG were screened by large-scale scRNA-sequence datasets. The machine learning algorithm established a 3-genes FRG index (FRGI). High FRGI represented a worse outcome. Then, FRGI combined clinical variables to construct a nomogram, which shows high predictive performance for the prognosis of bladder cancer. Furthermore, the BLCA datasets were separated into two subtypes - fibroblast hot and cold types. In five independent BLCA cohorts, the fibroblast hot type showed worse outcomes than the cold type. Multiple cancer-related hallmark pathways are distinctively enriched in these two types. In addition, high FRGI or fibroblast hot type shows a worse immune therapeutic response. Then, four subtypes called CD8-FRG subtypes were established under the combination of FRG signature and activity of CD8+ T-cells, which turned out to be effective in predicting the prognosis and immune therapeutic response of bladder cancer in multiple independent datasets. Pathway enrichment analysis, multiple gene signatures, and epigenetic alteration characterize the CD8-FRG subtypes and provide a potential combination strategy method against bladder cancer. CONCLUSIONS: In summary, we established a novel FRGI and CD8-FRG subtype by large-scale datasets and organized analyses, which could accurately predict clinical outcomes and immune therapeutic response of BLCA after surgery.

2.
J Inflamm Res ; 17: 3159-3171, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774448

RESUMO

Background: Sepsis is a life-threatening clinical syndrome caused by dysregulated host response to infection. The mechanism underlying sepsis-induced immune dysfunction remains poorly understood. Natural killer T (NKT) cells are cytotoxic lymphocytes that bridge the innate and adaptive immune systems, the role of NKT cells in sepsis is not entirely understood, and NKT cell cluster differences in sepsis remain unexplored. Methods: Mendelian randomization (MR) analyses were first conducted to investigate the causal relationship between side scatter area (SSC-A) on NKT cells and 28-day mortality of septic patients. A prospective and observational study was conducted to validate the relationship between the percentage of NKT cells and 28-day mortality of sepsis. Then, the single-cell RNA sequencing (scRNA-seq) data of peripheral blood mononuclear cells (PBMCs) from healthy controls and septic patients were profiled. Results: MR analyses first revealed the protective roles of NKT cells in the 28-day mortality of sepsis. Then, 115 septic patients were enrolled. NKT percentage was significantly higher in survivors (n = 84) compared to non-survivors (n = 31) (%, 5.00 ± 3.46 vs 2.18 ± 1.93, P < 0.0001). Patients with lower levels of NKT cells exhibited a significantly increased risk of 28-day mortality. According to scRNA-seq analysis, NKT cell clusters exhibited multiple distinctive characteristics, including a distinguishing cluster defined as FOS+NKT cells, which showed a significant decrease in sepsis. Pseudo-time analysis showed that FOS+NKT cells were characterized by upregulated expression of crucial functional genes such as GZMA and CCL4. CellChat revealed that interactions between FOS+NKT cells and adaptive immune cells including B cells and T cells were decreased in sepsis compared to healthy controls. Conclusion: Our findings indicate that NKT cells may protect against sepsis, and their percentage can predict 28-day mortality. Additionally, we discovered a unique FOS+NKT subtype crucial in sepsis immune response, offering novel insights into its immunopathogenesis.

3.
Int J Med Sci ; 21(6): 1129-1143, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774746

RESUMO

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of immune cells in the intima of arteries. Experimental and clinical evidence shows that both innate and adaptive immunity orchestrate the progression of atherosclerosis. The heterogeneous nature of immune cells within atherosclerosis lesions is important. Studies utilizing high-dimensional mass spectrometry and single-cell RNA sequencing of leukocytes from atherosclerotic lesions show the diversity and adaptability of these immune cell subtypes. Their migration, compositional changes, phenotypic alterations, and adaptive responses are key features throughout atherosclerosis progression. Understanding how these immune cells and their subtypes affect atherogenesis would help to develop novel therapeutic approaches that control atherosclerosis progression. Precise targeting of specific immune system components involved in atherosclerosis, rather than broad suppression of the immune system with anti-inflammatory agents, can more accurately regulate the progress of atherosclerosis with fewer side effects. In this review, we cover the most recent advances in the field of atherosclerosis to understand the role of various immune cells on its development. We focus on the complex network of immune cells and the interaction between the innate immune system and adaptive immune system.


Assuntos
Imunidade Adaptativa , Aterosclerose , Imunidade Inata , Humanos , Aterosclerose/imunologia , Animais , Progressão da Doença
4.
Small Methods ; : e2400436, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38763918

RESUMO

Organ-on-a-chip, also known as "tissue chip," is an advanced platform based on microfluidic systems for constructing miniature organ models in vitro. They can replicate the complex physiological and pathological responses of human organs. In recent years, the development of bone and joint-on-chip platforms aims to simulate the complex physiological and pathological processes occurring in human bones and joints, including cell-cell interactions, the interplay of various biochemical factors, the effects of mechanical stimuli, and the intricate connections between multiple organs. In the future, bone and joint-on-chip platforms will integrate the advantages of multiple disciplines, bringing more possibilities for exploring disease mechanisms, drug screening, and personalized medicine. This review explores the construction and application of Organ-on-a-chip technology in bone and joint disease research, proposes a modular construction concept, and discusses the new opportunities and future challenges in the construction and application of bone and joint-on-chip platforms.

5.
Quant Imaging Med Surg ; 14(5): 3572-3580, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38720868

RESUMO

Background: Endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic biliary balloon dilatation (PTBD) is a challenge in resolving biliary-enteric anastomotic occlusive strictures (BEAOS) and/or coexisting stones. The biliary-enteric anastomosis (BEA) often cannot be seen because of the surgically altered gastrointestinal anatomy. Here, a technique that combined percutaneous compliant-occluded distal cholangiography and the maintenance of a large-bore catheter is described to resolve this issue. Methods: A retrospective review of 10 patients who presented with BEAOS with/without coexisting stones who were treated with percutaneous compliant balloon-occluded distal cholangiography, bile duct stone removal, and the maintenance of a large-bore catheter between February 2017 and January 2021 was performed. Treatment response, laboratory examinations, including hepatic function tests, routine blood tests, and blood electrolytes, complications, and imaging data were evaluated. Paired t-tests were used to investigate the difference of laboratory examinations before and after the procedure. Results: All 10 cases were technically successful. A total of 9 stones in 6 patients were successfully removed by the compliant balloon. All catheters were removed after the patency of the stricture was confirmed by percutaneous transhepatic cholangiography (PTHC) 6 months later. No severe adverse events occurred during the perioperative period. There were 2 patients who experienced episodes of cholangitis during the follow-up period (mean, 17 months; range, 4-24 months), and neither BEAOS nor bile duct stones recurred within 2 years after the procedure. White blood cells (WBC), total bilirubin (TB), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were (6.0±1.4)×109/L and (6.0±1.6)×109/L (P=0.91), 31.4±15.7 and 29.6±10.3 µmol/L (P=0.74), 50.8±20.0 and 85.8±67.0 U/L (P=0.16), and 42.6±15.2 and 71.8±44.9 U/L (P=0.09) pre and postintervention, respectively. Conclusions: Percutaneous transhepatic compliant balloon-occluded distal cholangiography and the maintenance of a large-bore catheter probably provide an effective and safe alternative method for resolving BEAOS and/or coexisting stones.

6.
J Med Chem ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38736187

RESUMO

Although vaccination remains the prevalent prophylactic means for controlling Influenza A virus (IAV) infections, novel structural antivirus small-molecule drugs with new mechanisms of action for treating IAV are highly desirable. Herein, we describe a modular biomimetic strategy to expeditiously achieve a new class of macrocycles featuring oxime, which might target the hemagglutinin (HA)-mediated IAV entry into the host cells. SAR analysis revealed that the size and linker of the macrocycles play an important role in improving potency. Particularly, as a 14-membered macrocyclic oxime, 37 exhibited potent inhibitory activity against IAV H1N1 with an EC50 value of 23 nM and low cytotoxicity, which alleviated cytopathic effects and protected cell survival obviously after H1N1 infection. Furthermore, 37 showed significant synergistic activity with neuraminidase inhibitor oseltamivir in vitro.

7.
IEEE Trans Med Imaging ; PP2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739506

RESUMO

The size of image volumes in connectomics studies now reaches terabyte and often petabyte scales with a great diversity of appearance due to different sample preparation procedures. However, manual annotation of neuronal structures (e.g., synapses) in these huge image volumes is time-consuming, leading to limited labeled training data often smaller than 0.001% of the large-scale image volumes in application. Methods that can utilize in-domain labeled data and generalize to out-of-domain unlabeled data are in urgent need. Although many domain adaptation approaches are proposed to address such issues in the natural image domain, few of them have been evaluated on connectomics data due to a lack of domain adaptation benchmarks. Therefore, to enable developments of domain adaptive synapse detection methods for large-scale connectomics applications, we annotated 14 image volumes from a biologically diverse set of Megaphragma viggianii brain regions originating from three different whole-brain datasets and organized the WASPSYN challenge at ISBI 2023. The annotations include coordinates of pre-synapses and post-synapses in the 3D space, together with their one-to-many connectivity information. This paper describes the dataset, the tasks, the proposed baseline, the evaluation method, and the results of the challenge. Limitations of the challenge and the impact on neuroscience research are also discussed. The challenge is and will continue to be available at https://codalab.lisn.upsaclay.fr/competitions/9169. Successful algorithms that emerge from our challenge may potentially revolutionize real-world connectomics research and further the cause that aims to unravel the complexity of brain structure and function.

8.
J Psychosom Res ; 182: 111691, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38718690

RESUMO

OBJECTIVE: Major depressive disorder (MDD), anxiety disorders, and somatic symptom disorder (SSD) are associated with quality of life (QoL) reduction. This cross-sectional study investigated the relationship between these conditions as categorical diagnoses and related psychopathologies with QoL, recognizing their frequent overlap. METHODS: We recruited a total of 403 clinical patients and healthy individuals, administering diagnostic interviews based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. QoL and psychopathologies were assessed using the WHO Quality of Life-BREF (WHOQOL-BREF) and several self-administered questionnaires, respectively. Multiple linear regression analyses examined the associations between psychiatric diagnoses, psychopathologies, and QoL. RESULTS: SSD and MDD were independently associated with impaired global (ß = -0.318 and - 0.287) and all QoL domains (ß = -0.307, -0.150, -0.125, and - 0.133, in physical, psychological, social, and environmental domains respectively for SSD; ß = -0.278, -0.344, -0.275, and - 0.268 for MDD). The Beck Depression Inventory-II score showed pervasive associations with QoL (ß = -0.390, -0.408, -0.685, -0.463, and - 0.420, in global, physical, psychological, social, and environmental domains). The Patient Health Questionnaire-15 and Health Anxiety Questionnaire scores were associated with global (ß = -0.168 and - 0.181) and physical (ß = -0.293 and - 0.121) QoL domain, while the Cognitions About Body and Health Questionnaire score was only associated with environmental QoL domain (ß = -0.157). CONCLUSION: SSD and MDD were independently associated with QoL impairment. Depressive symptoms were associated with all QoL domains, whereas somatic symptom burden and health anxiety primarily affected the physical QoL domain. Clinicians should consider concomitant psychopathologies when managing patients with depression, anxiety, or somatic symptoms.

9.
Biomed Pharmacother ; 175: 116713, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38735083

RESUMO

Low specificity and hypoxia-induced drug resistance are significant challenges in traditional cancer treatment. To enhance the anticancer efficacy, an injectable hydrogel system is developed through the formation of dynamic covalent bonds in hyaluronic acid, allowing for localized controlled release of drugs. This system also utilizes double-stranded DNA sequences for the intercalation delivery of the chemotherapeutic drug, enabling a multifaceted approach to therapy. Cisplatin not only serves as a chemotherapy drug but also acts as a catalyst for chemodynamic therapy (CDT) to initiate CDT cascades by creating hydrogen peroxide for the Fenton reaction. Hemoglobin, enclosed in PLGA nanoparticles, provides ferrous ions that react with hydrogen peroxide in an acidic environment, yielding hydroxyl radicals that induce cancer cell death. Additionally, oxygen released from hemoglobin mitigates hypoxia-induced chemoresistance, bolstering overall anticancer efficacy. Results demonstrate the shear-thinning properties and injectability of the hydrogel. Cisplatin elevates intracellular hydrogen peroxide levels in tumor cells, while hemoglobin efficiently releases ferrous ions and generates reactive oxygen species (ROS) in the presence of hydrogen peroxide. In in vitro and in vivo study, the combinational use of chemo- and chemodynamic therapies achieves a synergistic anticancer effect on combating glioblastoma. In summary, our CDT-based hydrogel, activated by endogenous cues and mediated by chemo drugs, spontaneously produces ROS and ameliorates the adverse tumor microenvironment with rational and selective antitumor strategies.

10.
Radiol Cardiothorac Imaging ; 6(3): e230234, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38695742

RESUMO

Purpose To compare the tissue adequacy and diagnostic accuracy of US-guided biopsies of peripheral pulmonary lesions (PPLs) with and without contrast agents. Materials and Methods A retrospective study was conducted at four medical centers in patients with PPLs who underwent US-guided percutaneous transthoracic needle biopsy (PTNB) between January 2017 and October 2022. The patients were divided into contrast-enhanced US (CEUS) and US groups based on whether prebiopsy CEUS evaluation was performed. Tissue adequacy and the diagnostic accuracy of PTNB, stratified by lesion size, were analyzed and compared between groups. A propensity score matching (PSM) analysis was conducted using the nearest-neighbor matching method. Results A total of 1027 lesions were analyzed, with 634 patients (mean age, 59.4 years ± 13.0 [SD]; 413 male) in the US group and 393 patients (mean age, 61.2 years ± 12.5; 270 male) in the CEUS group. The CEUS group produced more acceptable samples than the US group (98.2% vs 95.7%; P = .03) and achieved higher diagnostic accuracy (96.9% vs 94.2%; P = .04), with no evidence of a difference in sensitivity (96.7% vs 94.0%; P = .06). PSM and stratified analyses (n = 358 per group) indicated higher tissue adequacy (99.0% vs 95.7%; P = .04) and diagnostic accuracy (98.5% vs 92.9%; P = .006) in the CEUS group compared with the US group for 2-7-cm PPLs but not for lesions larger than 7 cm. Conclusion PTNB with prebiopsy CEUS evaluation demonstrated significantly better tissue adequacy and diagnostic accuracy compared with US guidance alone for PPLs ranging from 2 to 7 cm, with similar biopsy performance achieved between groups for lesions larger than 7 cm. Keywords: Contrast Material, Thoracic Diseases, Ultrasonography, Image-Guided Biopsy © RSNA, 2024.


Assuntos
Meios de Contraste , Biópsia Guiada por Imagem , Ultrassonografia de Intervenção , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Biópsia Guiada por Imagem/métodos , Ultrassonografia de Intervenção/métodos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/patologia , Pulmão/diagnóstico por imagem , Idoso
11.
Comput Biol Med ; 175: 108386, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38691915

RESUMO

Optical Coherence Tomography (OCT) is a commonly used retina imaging technique, and it is capable of revealing the morphology of the choroid. However, the segmentation and quantitative analysis of the sublayers and vessels in choroid are rarely explored, primarily due to the indistinct boundaries of choroidal sublayers, and imbalanced distribution of vessels observed in OCT imagery. In this paper, we propose a novel two-stage architecture called Choroidal Layer Analysis network (CLA), that may be considered the first attempt in this research community for joint segmentation of choroidal sublayers and choroidal vessels in OCT images. CLA employs the encoder-decoder network with the residual U-shape module as the backbone. In order to empower the ability of the segmentation model to identify the inconspicuous boundaries of choroidal sublayers, we introduce an Ambiguous Boundary Attention block (ABA) into the bottleneck of the encoder-decoder network in the first stage. For more accurate segmentation of large choroidal vessels with ambiguous contours and imbalanced spatial distribution, the second stage introduces an active contour-based loss to refine the contours of choroidal vessels simultaneously with precise identification of each vessel via contextual modeling. To train, test and validate the proposed model, we conducted a choroidal segmentation dataset containing 800 OCT images, with their sublayers and large choroidal vessels manually annotated. Experimental results demonstrate the superiority of the proposed approach compared with other state-of-the-art segmentation networks in large margins. It is worth noting that we also reconstructed the large choroidal vessels in three-dimensional (3D) based on the segmentation results, and multiple 3D morphological parameters were calculated. The statistical analysis of these parameters demonstrates significant differences between the healthy control and high myopia group, and this further confirms the proposed work may facilitate subsequent disease understanding and clinical decision-making.


Assuntos
Corioide , Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Humanos , Corioide/diagnóstico por imagem , Corioide/irrigação sanguínea , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
12.
Sci Rep ; 14(1): 10296, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704464

RESUMO

This study combines laboratory experiments and discrete element simulation methods to analyze the mechanism and deterioration patterns of sandstone surrounding rock voiding the bottom of a heavy-haul railway tunnel. It is based on previously acquired measurement data from optical fiber grating sensors installed in the Taihangshan Mountain Tunnel of the Wari Railway. By incorporating rock particle wastage rate results, a method for calculating the peak strength and elastic modulus attenuation of surrounding rock is proposed. Research indicates that the operation of heavy-haul trains leads to an instantaneous increase in the dynamic water pressure on the bottom rock ranging 144.4-390.0%, resulting in high-speed water flow eroding the rock. After 1-2 years of operation, the bottom water and soil pressures increase by 526.5% and 390.0%, respectively. Focusing on sandstone surrounding rock with high observability, laboratory experiments were conducted to monitor the degradation stages of infiltration, particle loss, and voiding of rock under the action of dynamic water flow. The impact of water flow on the "cone-shaped" bottom rock deformation was also clarified. The extent of rock deterioration and voiding was determined using miniature water and soil pressure sensors in conjunction with discrete element numerical simulations. The measured rock particle loss was used as a criterion. Finally, a fitting approach is derived to calculate the peak strength and elastic modulus attenuation of surrounding rock, gaining insight into and providing a reference for the maintenance and disposal measures for the bottom operation of heavy-haul railway tunnels.

13.
J Cancer ; 15(10): 2891-2899, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706904

RESUMO

Breast cancer (BC) is one of the most common cancer types worldwide and the first cause of cancer-related deaths in women. Transient receptor potential vanillin 3 (TRPV3) has been preliminarily discovered to play an important role in various cancers, including BC. Here, we explored the effect of TRPV3 on breast cancer cells and its potential mechanism. TRPV3 level was measured in BC tissue and adjacent noncancerous breast tissue using real-time RT-PCR and Western blot. Wound healing was used to detect cell migration. MTT and EDU were detected cell proliferation. TUNEL and Caspase-3 activity were used to detect cell apoptosis. We found that TRPV3 expression significantly increased in both human BC tissues and breast cells line. TRPV3 siRNA (TRPV3 inhibition) dramatically suppressed cell migration and proliferation, promoted the apoptosis, and decreased [Ca2+]i; whereas Carvacrol (TRPV3 agonist) has opposite effect in MCF-7 cells. We validated EGFR (Epidermal growth factor receptor) is a direct target protein of TRPV3. Mechanism studies have shown that Carvacrol increased phosphorylation levels of EGFR and AKT, and were decreased by suppression of TRPV3. Moreover, Erlotinib (EGFR inhibitor) and LY294002 (PI3K inhibitor) diminished Carvacrol induced cell migration and proliferation, promoted cell apoptosis, and increased [Ca2+]i in Carvacrol group. Our results collectively suggest that TRPV3 siRNA inhibits migration and proliferation, and promoted apoptosis in breast cancer cells by EGFR/AKT pathway. These findings indicate that TRPV3 may represent a novel therapeutic strategy for breast cancer.

14.
Angew Chem Int Ed Engl ; : e202403241, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710651

RESUMO

Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single-cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events, however, the effects of mechanical force on vesicular release has been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4-ethylenedioxythiophene) conductive ink, which achieved real-time quantitation of strain-induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channel in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines release by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide a revealing insight on the regulatory effects of mechanical stimuli on vesicular exocytosis.

15.
Arthrosc Tech ; 13(4): 102898, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38690336

RESUMO

The main method for arthroscopic repair of the subscapularis is repair with suture anchors. The surgeon generally establishes the anterior and anterolateral operation portals to complete anchor implantation and suture passing, respectively. The single-operation portal technique has been developed recently. However, in the traditional single-operation portal technique, the suture device and grasper are difficult to operate simultaneously. In addition, with the traditional rotator cuff suture device, it is easy to cause further iatrogenic injury to the rotator cuff because of its larger diameter. Therefore, we describe a modified single-operation portal technique for suture passing percutaneously with a spinal needle taking into account the shortcomings of existing techniques. Our modified technique avoids the use of traditional suturing devices and effectively avoids further damage to the rotator cuff. The use of a single operation portal makes the operation more minimally invasive and simple and effectively avoids the problem of interference between the suture device and grasper in the same portal. The entire operational process does not require the use of costly consumables, resulting in increased cost-effectiveness and a significantly reduced operating time. In conclusion, our modified technique achieves the use of a single operation portal to suture the subscapularis through spinal needle suture passing, which has good clinical value.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38691288

RESUMO

Deep-sea mining inevitably produces plumes, which will pose a serious threat to the marine environment with the continuous movement and diffusion of plumes along with ocean currents. The terminal settling velocity (wt) of irregular particles is one of the crucial factors for determining the plumes' diffusion range. It is generally calculated by drag coefficient (CD), while most existing CD models only consider single shape characteristic parameter or have a smaller range of Reynolds number (Re). In this study, a new shape factor (γ) of irregular particles is proposed by considering the thickness (one-dimension), the projected area (two-dimension), and the surface area (three-dimension) of irregular particles as well as their coupling effect to establish a modified CD model for calculating the wt. A modified Gaussian plume model is proposed to predict the horizontal diffusion distance of the plume particles by considering the settling velocity and diffusion effect of irregular particles. Research results show that the wt increases nearly linearly, with a gradually decreased slope and slightly then greatly with the increasing of γ, dp (diameter) and ρp (density), respectively. The modified CD model is verified to be more valid with a wider application range (Re < 3×105) than five existing CD models by the test results. The larger the ρp or dp, the larger the wt and thus the smaller the Sh. This study could provide a theoretical basis for calculating the plume diffusion range to further study the impact of deep-sea mining on the ocean environment.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38691434

RESUMO

This article studies an emerging practical problem called heterogeneous prototype learning (HPL). Unlike the conventional heterogeneous face synthesis (HFS) problem that focuses on precisely translating a face image from a source domain to another target one without removing facial variations, HPL aims at learning the variation-free prototype of an image in the target domain while preserving the identity characteristics. HPL is a compounded problem involving two cross-coupled subproblems, that is, domain transfer and prototype learning (PL), thus making most of the existing HFS methods that simply transfer the domain style of images unsuitable for HPL. To tackle HPL, we advocate disentangling the prototype and domain factors in their respective latent feature spaces and then replacing the source domain with the target one for generating a new heterogeneous prototype. In doing so, the two subproblems in HPL can be solved jointly in a unified manner. Based on this, we propose a disentangled HPL framework, dubbed DisHPL, which is composed of one encoder-decoder generator and two discriminators. The generator and discriminators play adversarial games such that the generator embeds contaminated images into a prototype feature space only capturing identity information and a domain-specific feature space, while generating realistic-looking heterogeneous prototypes. Experiments on various heterogeneous datasets with diverse variations validate the superiority of DisHPL.

18.
Opt Lett ; 49(9): 2521-2524, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691759

RESUMO

Quantum key distribution allows secret key generation with information theoretical security. It can be realized with photonic integrated circuits to benefit the tiny footprints and the large-scale manufacturing capacity. Continuous-variable quantum key distribution is suitable for chip-based integration due to its compatibility with mature optical communication devices. However, the quantum signal power control compatible with the mature photonic integration process faces difficulties on stability, which limits the system performance and causes the overestimation of a secret key rate that opens practical security loopholes. Here, a highly stable chip-based quantum signal power control scheme based on a biased Mach-Zehnder interferometer structure is proposed, theoretically analyzed, and experimentally implemented with standard silicon photonic techniques. Simulations and experimental results show that the proposed scheme significantly improves the system stability, where the standard deviation of the secret key rate is suppressed by an order of magnitude compared with the system using traditional designs, showing a promising and practicable way to realize a highly stable continuous-variable quantum key distribution system on chip.

19.
Haematologica ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695130

RESUMO

Venous Thromboembolism (VTE) is a complex disease that can be classified into two subtypes: Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE). Previous observational studies have shown associations between lipids and VTE, but causality remains unclear. Hence, by utilizing 241 lipid-related traits as exposures and data from the FinnGen consortium on VTE, DVT, and PE as outcomes, we conducted two-sample Mendelian randomization (MR) analysis to investigate causal relationships between lipids and VTE, DVT and PE. The MR results identified that fatty acid (FA) unsaturation traits (Ratio of bis-allylic bonds to double bonds in lipids, and Ratio of bis-allylic bonds to total fatty acids in lipids) were associated with VTE (OR [95% CI]: 1.21 [1.15-1.27]; 1.21 [1.13-1.30]), DVT (OR [95%CI]: 1.24 [1.16-1.33]; 1.26 [1.16-1.36]) and PE (OR [95%CI]: 1.18 [1.08-1.29]; 1.18 [1.09-1.27]). Phosphatidylcholines exhibit potential causal effects on VTE and PE. Phosphatidylcholine acyl-alkyl C40:4 (PC ae C40:4) was negatively associated with VTE (OR [95% CI]: 0.79 [0.73-0.86]), while phosphatidylcholine diacyl C42:6 (PC aa C42:6) and phosphatidylcholine acyl-alkyl C36:4 (PC ae C36:4) were positively associated with PE (OR [95%CI]: 1.44 [1.20-1.72]; 1.22 [1.10-1.35]). Additionally, we found that medium LDL had a protective effect on VTE. Our study indicates that higher FA unsaturation may increase the risk of VTE, DVT, and PE. Different types of phosphatidylcholine have either promotive or inhibitory effects on VTE and PE, contributing to a better understanding of the risk factors for VTE.

20.
Biomaterials ; 309: 122593, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38713971

RESUMO

Posterior capsule opacification (PCO) is a predominant postoperative complication, often leading to visual impairment due to the aberrant proliferation and adhesion of lens epithelial cells (LECs) and protein precipitates subsequent to intraocular lens (IOL) implantation. To address this clinical issue, a foldable and antifouling sharp-edged IOL implant based on naturally-derived cellulose hydrogel is synthesized. The mechanical strength and transparency of the hydrogel is enhanced via repeated freeze-thaw (FT) cycles. The incorporated zwitterionic modifications can remarkably prevent the incidence of PCO by exhibiting proteins repulsion and cell anti-adhesion properties. The graft of dopamine onto both the haptic and the periphery of the posterior surface ensures the adhesion of the hydrogel to the posterior capsule and impedes the migration of LECs without compromising transparency. In in vivo study, the zwitterionic modified foldable hydrogel exhibits uveal and capsular biocompatibility synchronously with no signs of inflammatory response and prevent PCO formation, better than that of commercialized and PEG-modified IOL. With foldability, endurability, antifouling effect, and adhesive to posterior capsule, the reported hydrogel featuring heterogeneous surface design displays great potential to eradicate PCO and attain post-operative efficacy after cataract surgery.

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