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1.
Nature ; 613(7943): 274-279, 2023 01.
Article in English | MEDLINE | ID: mdl-36631650

ABSTRACT

The development of next-generation electronics requires scaling of channel material thickness down to the two-dimensional limit while maintaining ultralow contact resistance1,2. Transition-metal dichalcogenides can sustain transistor scaling to the end of roadmap, but despite a myriad of efforts, the device performance remains contact-limited3-12. In particular, the contact resistance has not surpassed that of covalently bonded metal-semiconductor junctions owing to the intrinsic van der Waals gap, and the best contact technologies are facing stability issues3,7. Here we push the electrical contact of monolayer molybdenum disulfide close to the quantum limit by hybridization of energy bands with semi-metallic antimony ([Formula: see text]) through strong van der Waals interactions. The contacts exhibit a low contact resistance of 42 ohm micrometres and excellent stability at 125 degrees Celsius. Owing to improved contacts, short-channel molybdenum disulfide transistors show current saturation under one-volt drain bias with an on-state current of 1.23 milliamperes per micrometre, an on/off ratio over 108 and an intrinsic delay of 74 femtoseconds. These performances outperformed equivalent silicon complementary metal-oxide-semiconductor technologies and satisfied the 2028 roadmap target. We further fabricate large-area device arrays and demonstrate lowĀ variability in contact resistance, threshold voltage, subthreshold swing, on/off ratio, on-state current and transconductance13. The excellent electrical performance, stability and variability make antimony ([Formula: see text]) a promising contact technology for transition-metal-dichalcogenide-based electronics beyond silicon.

2.
Nature ; 605(7908): 69-75, 2022 05.
Article in English | MEDLINE | ID: mdl-35508774

ABSTRACT

Two-dimensional transition-metal dichalcogenides (TMDs) are of interest for beyond-silicon electronics1,2. It has been suggested that bilayer TMDs, which combine good electrostatic control, smaller bandgap and higher mobility than monolayers, could potentially provide improvements in the energy-delay product of transistors3-5. However, despite advances in the growth of monolayer TMDs6-14, the controlled epitaxial growth of multilayers remains a challenge15. Here we report the uniform nucleation (>99%) of bilayer molybdenum disulfide (MoS2) on c-plane sapphire. In particular, we engineer the atomic terrace height on c-plane sapphire to enable an edge-nucleation mechanism and the coalescence of MoS2 domains into continuous, centimetre-scale films. Fabricated field-effect transistor (FET) devices based on bilayer MoS2 channels show substantial improvements in mobility (up to 122.6 cm2 V-1 s-1) and variation compared with FETs based on monolayer films. Furthermore, short-channel FETs exhibit an on-state current of 1.27 mA Āµm-1, which exceeds the 2028 roadmap target for high-performance FETs16.

3.
Zhonghua Nan Ke Xue ; 30(4): 368-373, 2024 Apr.
Article in Zh | MEDLINE | ID: mdl-39210425

ABSTRACT

Prostate cancer (PCa) ranks as the second most prevalent malignancy among males worldwide at present, and its prevalence keeps rising. Focal therapy not only results in tumor necrosis but also encourages the release of autoantigens originating from the tumor into the bloodstream and activates the host immune system to effectively fight the tumor. However, focal therapy alone may not achieve the total ablation of cancer cells and may cause locoregional recurrence. Immunotherapy, by boosting the body's immune response, destroys tumor cells and prevents immune escape. Recent studies show that focal therapy combined with immunotherapy can produce a better clinical efficacy by enhancing the initial immune response, especially for low- to intermediate-risk confined PCa. This article offers some fresh perspectives on the management of PCa by reviewing the etiology and progression of the malignancy, focal therapeutic options, and advantages and vista of focal therapy combined with immunotherapy.


Subject(s)
Immunotherapy , Prostatic Neoplasms , Humans , Prostatic Neoplasms/therapy , Prostatic Neoplasms/immunology , Immunotherapy/methods , Male , Combined Modality Therapy
4.
Magn Reson Med ; 89(5): 2062-2075, 2023 05.
Article in English | MEDLINE | ID: mdl-36656129

ABSTRACT

PURPOSE: To improve the MRI reconstruction performance of model-based networks and to alleviate their large demand for GPU memory. METHODS: A model-based neural network with enhanced deep learned regularizers (MEDL-Net) was proposed. The MEDL-Net is separated into several submodules, each of which consists of several cascades to mimic the optimization steps in conventional MRI reconstruction algorithms. Information from shallow cascades is densely connected to latter ones to enrich their inputs in each submodule, and additional revising blocks (RB) are stacked at the end of the submodules to bring more flexibility. Moreover, a composition loss function was designed to explicitly supervise RBs. RESULTS: Network performance was evaluated on a publicly available dataset. The MEDL-Net quantitatively outperforms the state-of-the-art methods on different MR image sequences with different acceleration rates (four-fold and six-fold). Moreover, the reconstructed images showed that the detailed textures are better preserved. In addition, fewer cascades are required when achieving the same reconstruction results compared with other model-based networks. CONCLUSION: In this study, a more efficient model-based deep network was proposed to reconstruct MR images. The experimental results indicate that the proposed method improves reconstruction performance with fewer cascades, which alleviates the large demand for GPU memory.


Subject(s)
Image Processing, Computer-Assisted , Neural Networks, Computer , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Algorithms , Acceleration
5.
Microb Pathog ; 175: 105981, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36642286

ABSTRACT

Vibrio splendidus, a gram-negative bacterium that is ubiquitously present in marine environments, has been increasingly deemed an important opportunistic pathogen of marine animals. In this study, the biofilm formation of V. splendidus was quantitatively determined and morphologically characterized. Three stages of biofilm formation, including adhesion, aggregation and maturation were observed in the biofilm formed by V. splendidus. The inhibitory effect of exogenous bis (3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) on the biofilm formation from the scratch and preformed established biofilms of V. splendidus was determined. When 200Ā Āµmol/L c-di-GMP was added, the quantity of biofilm decreased by 88.1% or 66.7% under the two conditions. To explore the preliminary mechanism of exogenous c-di-GMP on the biofilm formed by V. splendidus, proteomic analysis was performed. GO enrichment analysis showed that exogenous c-di-GMP upregulated biological processes, including the tricarboxylic acid cycle, oxidationĆ¢Ā€Ā’reduction reactions and organonitrogen compound catabolism and significantly downregulated tRNA threonylcarbamoyladenosine modification, protein dephosphorylation, and lactate transmembrane transporter activity. Sequence-specific DNA binding activity was the most markedly downregulated molecular function. KEGG analysis showed that the valine, leucine and isoleucine degradation pathway was the most enriched pathway, followed by nitrogen metabolism, among the 20 upregulated pathways. Among the downregulated pathways, a nonribosomal peptide structure pathway and the streptomycine, polyketide sugar unit, acarbose and validamycin biosynthesis pathways were significantly enriched. Our present study provides basic data for the biofilm formation of V. splendidus and the preliminary inhibitory mechanism of exogenous c-di-GMP on the biofilm formation of V. splendidus.


Subject(s)
Proteomics , Vibrio cholerae , Vibrio cholerae/genetics , Cyclic GMP/metabolism , Biofilms , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Gene Expression Regulation, Bacterial
6.
Appl Microbiol Biotechnol ; 107(7-8): 2533-2546, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36922441

ABSTRACT

Vibrio splendidus is a ubiquitous Gram-negative marine bacterium that causes diseases within a wide range of marine cultured animals. Since iron deprivation is the frequent situation that the bacteria usually encounter, we aimed to explore the effect of iron deprivation on the proteomic profile of V. splendidus in the present study. There were 425 differentially expressed proteins (DEPs) responded to the iron deprivation condition. When the cells were grown under iron deprivation condition, the oxidationĆ¢Ā€Ā’reduction processes, single-organism metabolic processes, the catalytic activity, and binding activity were downregulated, while the transport process, membrane cell component, and ion binding activity were upregulated, apart from the iron uptake processes. Kyoto Encyclopedia of Genes and Genomes analysis showed that various metabolism pathways, biosynthesis pathways, energy generation pathways of tricarboxylic acid cycle, and oxidative phosphorylation were downregulated, while various degradation pathways and several special metabolism pathways were upregulated. The proteomic profiles of cells at a OD600 ≈ 0.4 grown under iron deprivation condition showed high similarity to that of the cells at a OD600 ≈ 0.8 grown without iron chelator 2,2'-bipyridine. Correspondingly, the protease activity, the activity of autoinducer 2 (AI-2), and indole content separately catalyzed by LuxS and TnaA, were measured to verify the proteomic data. Our present study gives basic information on the global protein profiles of V. splendidus grown under iron deprivation condition and suggests that the iron deprivation condition cause the cell growth enter a state of higher cell density earlier. KEY POINTS: Ć¢Ā€Ā¢ Adaptation of V. splendidus to iron deprivation was explored by proteomic analysis. Ć¢Ā€Ā¢ GO and KEGG of DEPs under different iron levels or cell densities were determined. Ć¢Ā€Ā¢ Iron deprivation caused the cell enter a state of higher cell density earlier.


Subject(s)
Proteomics , Vibrio , Animals , Vibrio/genetics , Iron/metabolism , Oxidation-Reduction
7.
Pestic Biochem Physiol ; 195: 105576, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37666602

ABSTRACT

Herbicide resistance is rapidly emerging in Cyperus difformis in rice fields across China. The response of a C. difformis population GX-35 was tested against five acetolactate synthase (ALS)-inhibiting herbicides, auxin herbicide MCPA and photosynthesis II (PSII)-inhibitor bentazone. Population GX-35 evolved multiple resistance to ALS-inhibiting herbicides (penoxsulam, bispyribacĀ­sodium, pyrazosulfuron-ethyl, halosulfuron-methly and imazapic) and auxin herbicide MCPA, with resistance levels of 140-, 1253-, 578-, 18-, 13-, and 21-fold, respectively, compared to the susceptible population. In this population, ALS gene expression was similar to that of the susceptible population. However, an Asp376Glu mutation in ALS gene was observed, leading to reduced inhibition of in-vitro ALS activities by five ALS-inhibiting herbicides. Furthermore, CYP71D8, CYP77A3, CYP78A5 and three ABC transporter genes (cluster-14412.23067, cluster-14412.25321, and cluster-14412.24716) over-expressed in absence of penoxsulam. On the other hand, an UGT73C1 and an ABC transporter (cluster-14412.25038) were induced by penoxsulam. Additionally, both over-expression and induction were observed for CYP74, CYP71A1, UGT88A1 and an ABC transporter (cluster-14412.21723). The GX-35 population has indeed evolved multiple herbicide resistance in China. Therefore, a diverse range of weed control tactics should be implemented in rice field.


Subject(s)
2-Methyl-4-chlorophenoxyacetic Acid , Acetolactate Synthase , Cyperus , Herbicides , Oryza , Oryza/genetics , Herbicide Resistance/genetics , China , ATP-Binding Cassette Transporters , Acetolactate Synthase/genetics , Herbicides/pharmacology , Indoleacetic Acids
8.
World J Microbiol Biotechnol ; 39(5): 116, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36918451

ABSTRACT

Vibrio splendidus is a ubiquitous pathogen that causes various diseases in aquaculture with a wide range of hosts. In our previous studies, we showed that L-glutamic acid was the optimal carbon source that could revive V. splendidus persister cells. In our present study, single cell observation under microscopy showed that V. splendidus could revive using L-glutamic acid as carbon source. A proteomic analysis was carried out to further illustrate the initial wake up of persister cells with L-glutamic acid. To collect the initially revived cells, SDS-PAGE was used to determine the revived time. The total proteins from the persister cells and the revived cells were analyzed using LCĆ¢Ā€Ā’MS/MS. A total of 106 proteins, including 42 downregulated proteins and 64 upregulated proteins, were identified. GO analysis of the differentially expressed proteins (DEPs) showed that biological processes, including protein complex assembly, protein oligomerization, and arginine metabolism; cellular components, including extracellular membrane, plasma membrane and ribosome; and molecular functions, including the activities of arginine binding and structural constituent of ribosome, were enriched. KEGG analysis showed that lipopolysaccharide biosynthesis, porphyrin and chlorophyll metabolism, and peptidoglycan biosynthesis were upregulated, while the ribosome was downregulated. This is the first time to study the initial wake up of persister cells based on proteomic analysis, and the results revealed the main pathways involved in the early resuscitation of V. splendidus persister cells.


Subject(s)
Glutamic Acid , Vibrio , Glutamic Acid/metabolism , Proteomics , Chromatography, Liquid , Tandem Mass Spectrometry , Vibrio/metabolism , Proteins/metabolism , Arginine/metabolism
9.
Biol Reprod ; 106(4): 687-698, 2022 04 26.
Article in English | MEDLINE | ID: mdl-34935917

ABSTRACT

Assisted reproductive technology (ART) has been used globally among infertile couples. However, many epidemiological investigations have indicated that ART is associated with a range of long-term adverse health outcomes in offspring, including cardiovascular disease, obesity, and increased plasma lipid levels. Until now, direct evidence has been limited regarding the pathological changes in vascular function in fetuses with ART. In this study, human umbilical cords were collected from healthy normal pregnancies and in vitro fertilization and embryo transfer (IVF-ET) pregnancies. Vascular functional studies involving acetylcholine (ACh), antagonists of its specific receptors, and L-type calcium channel/PKC-MLC20 phosphorylation pathway specific inhibitors were conducted. Quantitative real-time PCR, Western blotting, and methylation analyses were performed on umbilical vein samples. We found that the umbilical vein constriction induced by ACh in the IVF-ET group was significantly attenuated compared with that in the healthy normal pregnancy group, which was not only associated with the hypermethylation of ACh muscarinic receptor subtype 3 (CHRM3) and decreased expression of CHRM3, PKCƟ, and CaV1.2, but was also related to the reduced phosphorylation of MLC20. This study revealed that the hypermethylation of CHRM3, leading to a reduction in CHRM3 expression and downregulation of the CaV1.2/PKC-MLC20 phosphorylation pathway, was responsible for the decreased sensitivity to ACh observed in the umbilical vein under IVF-ET conditions. The hypermethylation of CHRM3 caused by IVF-ET might play an important role in altered vasoconstriction and impact cardiovascular systems in the long run.


Subject(s)
Embryo Transfer , Receptor, Muscarinic M3 , Reproductive Techniques, Assisted , Acetylcholine , DNA Methylation , Embryo Transfer/methods , Female , Fertilization in Vitro/methods , Humans , Pregnancy , Receptor, Muscarinic M3/metabolism , Umbilical Veins
10.
Ecotoxicol Environ Saf ; 239: 113682, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35643027

ABSTRACT

Fluoride exposure has a detrimental effect on neurodevelopment, while the underlying processes remain unknown. The goal of this study was to investigate how fluoride impacts synaptogenesis, with a focus on the phosphorylation of Creb1 (p-Creb1)-brain-derived neurotrophic factor (BDNF)-tyrosine kinase B (TrkB) pathway. We generated a sodium fluoride (NaF) model using C57 BL/6Ā J mice exposed to 100Ā mg/L NaF from gestation day 1 (GD1) to GD20. It was identified that NaF treatment impaired the learning and memory abilities of the male offspring, reduced dendritic spine density, lowered postsynaptic density protein-95 (PSD95) and synaptophysin (SYN) expression in the male offspring's hippocampus, indicating that synaptic dysfunction may contribute to the cognitive impairment in the NaF model. In addition, in vivo experiment demonstrated that the protein abundance of BDNF and the ratio of p-Creb1 to Creb1 were increased in the hippocampus of NaF offspring, while the level of TrkB was reduced. Similarly, PC12 cells treated with NaF also showed increased expression of BDNF and decreased levels of TrkB. Notably, fluoride treatment increased p-Creb1 in vitro, while inhibiting p-Creb1 by 66615 significantly alleviated the effects of NaF exposure, indicating that p-Creb1 exerts a regulatory function in the BDNF-TrkB pathway. Altogether, these results demonstrated prenatal fluoride exposure triggered neurotoxicity in the male offspring hippocampus was linked to synaptogenesis damage caused by activating p-Creb1, which disrupted the BDNF-TrkB pathway.


Subject(s)
Brain-Derived Neurotrophic Factor , Cyclic AMP Response Element-Binding Protein , Fluorides , Prenatal Exposure Delayed Effects , Receptor, trkB , Animals , Brain-Derived Neurotrophic Factor/metabolism , Cognition , Cyclic AMP Response Element-Binding Protein/metabolism , Female , Fluorides/toxicity , Hippocampus/metabolism , Male , Mice , Mice, Inbred C57BL , Phosphorylation , Pregnancy , Prenatal Exposure Delayed Effects/physiopathology , Protein-Tyrosine Kinases/metabolism , Rats , Receptor, trkB/metabolism , Signal Transduction
11.
Entropy (Basel) ; 23(10)2021 Oct 19.
Article in English | MEDLINE | ID: mdl-34682086

ABSTRACT

Multi-focus image fusion is an important method used to combine the focused parts from source multi-focus images into a single full-focus image. Currently, to address the problem of multi-focus image fusion, the key is on how to accurately detect the focus regions, especially when the source images captured by cameras produce anisotropic blur and unregistration. This paper proposes a new multi-focus image fusion method based on the multi-scale decomposition of complementary information. Firstly, this method uses two groups of large-scale and small-scale decomposition schemes that are structurally complementary, to perform two-scale double-layer singular value decomposition of the image separately and obtain low-frequency and high-frequency components. Then, the low-frequency components are fused by a rule that integrates image local energy with edge energy. The high-frequency components are fused by the parameter-adaptive pulse-coupled neural network model (PA-PCNN), and according to the feature information contained in each decomposition layer of the high-frequency components, different detailed features are selected as the external stimulus input of the PA-PCNN. Finally, according to the two-scale decomposition of the source image that is structure complementary, and the fusion of high and low frequency components, two initial decision maps with complementary information are obtained. By refining the initial decision graph, the final fusion decision map is obtained to complete the image fusion. In addition, the proposed method is compared with 10 state-of-the-art approaches to verify its effectiveness. The experimental results show that the proposed method can more accurately distinguish the focused and non-focused areas in the case of image pre-registration and unregistration, and the subjective and objective evaluation indicators are slightly better than those of the existing methods.

12.
Biochem Biophys Res Commun ; 493(1): 585-591, 2017 11 04.
Article in English | MEDLINE | ID: mdl-28867187

ABSTRACT

Irisin is a newly identified myokine that may be cancer-associated, and its impact on liver cancer is unclear. To understand the roles of irisin in liver cancer, we investigated its effect in HepG2 and SMCC7721 hepatocellular carcinoma cells, and the underlying mechanisms. We determined irisin levels in liver tissues and serum samples obtained from patients by using real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Irisin levels in cancerous livers were significantly upregulated compared with those in control livers, but serum irisin levels remained unchanged. Additionally, we evaluated the effects of different concentrations of human recombinant modified and active (glycosylated) irisin (IM) or human recombinant nonmodified irisin (INM) on cell migration, proliferation, viability, and invasiveness. CCK8, transwell, and scratching assays demonstrated that irisin significantly increased cell proliferation, invasion, and migration through activation of the PI3K/AKT pathway. Irisin-induced cell proliferation, migration, and invasion were blocked by a PI3K inhibitor (LY294002). Irisin also decreased the cytotoxicity of doxorubicin in HepG2 cells. These data indicate that increased irisin levels may have protective roles in liver cancer cells through partial activation of the PI3K/AKT pathway, which may facilitate liver cancer progression and decrease the sensitivity to chemotherapy.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Fibronectins/metabolism , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Proto-Oncogene Proteins c-akt/metabolism , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Neoplasm Invasiveness , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Tumor Cells, Cultured
13.
J Reprod Dev ; 62(5): 487-493, 2016 Oct 18.
Article in English | MEDLINE | ID: mdl-27319751

ABSTRACT

Although a large number of studies show that photo-period disruption potentially affects hormone secretion in mammals, information about the effects of circadian photo-period disruption during pregnancy on fetal blood reproductive hormone levels is scarce. This study used ewes and their fetuses to determine the effects of circadian photo-period disruption (deprivation of darkness) on follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone in maternal and fetal circulation at late gestation. Pregnant ewes (gestational age: 135 Ā± 3 days) were randomly placed into control and dark deprivation groups. The control (N = 5) and dark deprivation (N = 5) groups were exposed to a fixed 12 h light/12 h dark cycle and a 24 h constant light cycle, respectively, for 2 days. Dark deprivation up-regulated follicle-stimulating hormone and estradiol levels and down-regulated progesterone levels in both maternal and fetal circulation, and up-regulated luteinizing hormone levels in fetal but not maternal circulation. These results provide new information about how circadian photo-period disruption during pregnancy could alter the release of certain reproductive hormones into fetal blood, which may influence the development of fetal organs in utero, as well as long-term health.


Subject(s)
Circadian Rhythm , Estradiol/blood , Follicle Stimulating Hormone/blood , Luteinizing Hormone/blood , Photoperiod , Progesterone/blood , Animals , Female , Fetal Blood , Gene Expression Regulation, Developmental , Pregnancy , Pregnancy, Animal , Radioimmunoassay , Random Allocation , Sheep , Sheep, Domestic
14.
Cell Biochem Funct ; 33(2): 51-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25703688

ABSTRACT

Hypoxia could stimulate proliferation of mesenchymal stem cells (MSCs) under certain conditions. This study determined angiotensin II mechanisms and PI3K/AKT pathway in hypoxia-induced proliferation of MSCs. Hypoxia (3% oxygen) induced cellular proliferation in mouse MSCs and upregulated endogenous angiotensin II and angiotensin-converting enzyme in the cell culture and expression of AT1 receptors. The expressions of Sox2, not Oct4 and Rex1, were significantly increased by the hypoxia. The blockade of AT1 receptors, not AT2 receptors, depressed hypoxia induced the proliferative effects. Both hypoxia and exogenous angiotensin II activated p-AKT. Moreover, AT1 receptor inhibitor blocked the effects of hypoxia-mediated p-AKT upregulation. The data demonstrated that the hypoxia at 3% oxygen level could induce mouse MSC proliferation, probably as a result of the activation of PI3K signalling pathways via AT1 receptors.


Subject(s)
Angiotensin II/metabolism , Cell Hypoxia , Cell Proliferation , Mesenchymal Stem Cells/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Animals , Cells, Cultured , Mice , Transcription Factors/metabolism
15.
Ecotoxicol Environ Saf ; 104: 23-7, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24632119

ABSTRACT

The dissipation and residue levels of rotenone with suspension concentrate (SC) as well as water dispersible granule (WDG) formulations in cabbage and soil were investigated under field conditions. The decline curves of rotenone residues in cabbage and soil corresponded with first-order kinetics. The dissipation rate of rotenone in cabbage was faster than that in soil. The half-lives of the SC formulations in cabbage and soil were 1.14d to 1.85d and 2.26d to 3.98d, respectively. For the WDG formulation, the values were 1.33d to 1.96d and 2.41d to 3.38d. Less spraying, lower dosage, and longer pre-harvest intervals could reduce terminal residue levels. Terminal residues below the MRL (0.5mg kg(-1)) were achieved after pre-harvest intervals of 3d at either once (45g a.i. ha(-1)) or twice (90g a.i. ha(-1)) the recommended dosage. The different dissipation processes of rotenone in cabbage and soil under field conditions could be attributed to the different climate and soil properties, and the types of formulation had no apparent effect on half-life. Formulation type affected the initial concentrations and finally led to different terminal residues. Prolonged pre-harvest intervals are necessary to ensure that the products are sufficiently safe for consumption.


Subject(s)
Brassica/chemistry , Pesticide Residues/analysis , Rotenone/analysis , Soil Pollutants/analysis , Soil/chemistry , Climate , Environmental Monitoring , Half-Life
16.
Neural Netw ; 174: 106231, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38521017

ABSTRACT

Collaborative representation-based (CR) methods have become prevalent for pattern classification tasks, achieving formidable performance. Theoretically, we expect the learned class-specific representation of the correct class to be discriminative against others, with the representation of the correct class contributing dominantly in CR. However, most existing CR methods focus on improving discrimination while having a limited impact on enhancing the representation contribution of the correct category. In this work, we propose a novel CR approach for image classification called the elastic competitive and discriminative collaborative representation-based classifier (ECDCRC) to simultaneously strengthen representation contribution and discrimination of the correct class. The ECDCRC objective function penalizes two key terms by fully incorporating label information. The competitive term integrates the nearest subspace representation with corresponding elastic factors into the model, allowing each class to have varying competition intensities based on similarity with the query sample. This enhances the representation contribution of the correct class in CR. To further improve discrimination, the discriminative term introduces an elastic factor as a weight in the model to represent the gap between the query sample and the representation of each class. Moreover, instead of focusing on representation coefficients, the designed ECDCRC weights associated with representation components directly relate to the representation of each class, enabling more direct and precise discrimination improvement. Concurrently, sparsity is also enhanced through the two terms, further boosting model performance. Additionally, we propose a robust ECDCRC (R-ECDCRC) to handle image classification with noise. Extensive experiments on seven public databases demonstrate the proposed method's superior performance over related state-of-the-art CR methods.


Subject(s)
Learning , Databases, Factual
17.
IEEE Trans Image Process ; 33: 4614-4626, 2024.
Article in English | MEDLINE | ID: mdl-39159025

ABSTRACT

In scenarios where identifying face information in the visible spectrum (VIS) is challenging due to poor lighting conditions, the use of near-infrared (NIR) and thermal (TH) cameras can provide viable alternatives. However, the unique data distribution of images captured by these cameras compared to VIS images presents challenges in matching face identities. To address these challenges, we propose a novel image transformation framework. The framework includes feature extraction from the input image, followed by a transformation network that generates target domain images with perceptual fidelity. Additionally, a reconstruction network preserves original information by reconstructing the original domain image from the extracted features. By considering the correlation between features from both domains, our framework utilizes paired data obtained from the same individual. We apply this framework to two well-established image-to-image transformation models, pix2pix and CycleGAN, known as CRC-pix2pix and CRC-CycleGAN respectively. The versatility of our approach allows extension to other models based on pix2pix or CycleGAN architectures. Our models generate high-quality images while preserving the identity information of the original face. Performance evaluation on TFW and BUAA NIR-VIS datasets demonstrates the superiority of our models in terms of generated image face matching and evaluation metrics such as SSIM, MSE, PSNR, and LPIPS. Moreover, we introduce the CQUPT-VIS-TH dataset, which enriches the paired dataset with thermal-visual face data capturing various angles and expressions.

18.
Comput Biol Med ; 173: 108381, 2024 May.
Article in English | MEDLINE | ID: mdl-38569237

ABSTRACT

Multimodal medical image fusion (MMIF) technology plays a crucial role in medical diagnosis and treatment by integrating different images to obtain fusion images with comprehensive information. Deep learning-based fusion methods have demonstrated superior performance, but some of them still encounter challenges such as imbalanced retention of color and texture information and low fusion efficiency. To alleviate the above issues, this paper presents a real-time MMIF method, called a lightweight residual fusion network. First, a feature extraction framework with three branches is designed. Two independent branches are used to fully extract brightness and texture information. The fusion branch enables different modal information to be interactively fused at a shallow level, thereby better retaining brightness and texture information. Furthermore, a lightweight residual unit is designed to replace the conventional residual convolution in the model, thereby improving the fusion efficiency and reducing the overall model size by approximately 5 times. Finally, considering that the high-frequency image decomposed by the wavelet transform contains abundant edge and texture information, an adaptive strategy is proposed for assigning weights to the loss function based on the information content in the high-frequency image. This strategy effectively guides the model toward preserving intricate details. The experimental results on MRI and functional images demonstrate that the proposed method exhibits superior fusion performance and efficiency compared to alternative approaches. The code of LRFNet is available at https://github.com/HeDan-11/LRFNet.


Subject(s)
Image Processing, Computer-Assisted , Wavelet Analysis
19.
Natl Sci Rev ; 11(3): nwae001, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38312376

ABSTRACT

This Perspective aims to provide a concise survey of current progress and outlook future directions in high-performance transistors and integrated circuits (ICs) based on 2D semiconductors.

20.
Comput Biol Med ; 169: 107931, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38181608

ABSTRACT

Colorectal cancer is a common malignant tumor of the digestive tract. Most colorectal cancer is caused by colorectal polyp lesions. Timely detection and removal of colorectal polyps can substantially reduce the incidence of colorectal cancer. Accurate polyp segmentation can provide important polyp information that can aid in the early diagnosis and treatment of colorectal cancer. However, polyps of the same type can vary in texture, color, and even size. Furthermore, some polyps are similar in colour to the surrounding healthy tissue, which makes the boundary between the polyp and the surrounding area unclear. In order to overcome the issues of inaccurate polyp localization and unclear boundary segmentation, we propose a polyp segmentation network based on cross-level information fusion and guidance. We use a Transformer encoder to extract a more robust feature representation. In addition, to refine the processing of feature information from encoders, we propose the edge feature processing module (EFPM) and the cross-level information processing module (CIPM). EFPM is used to focus on the boundary information in polyp features. After processing each feature, EFPM can obtain clear and accurate polyp boundary features, which can mitigate unclear boundary segmentation. CIPM is used to aggregate and process multi-scale features transmitted by various encoder layers and to solve the problem of inaccurate polyp location by using multi-level features to obtain the location information of polyps. In order to better use the processed features to optimise our segmentation effect, we also propose an information guidance module (IGM) to integrate the processed features of EFPM and CIPM to obtain accurate positioning and segmentation of polyps. Through experiments on five public polyp datasets using six metrics, it was demonstrated that the proposed network has better robustness and more accurate segmentation effect. Compared with other advanced algorithms, CIFG-Net has superior performance. Code available at: https://github.com/zspnb/CIFG-Net.


Subject(s)
Algorithms , Colorectal Neoplasms , Humans , Benchmarking , Cognition , Image Processing, Computer-Assisted
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