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1.
Biomimetics (Basel) ; 9(5)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38786491

RESUMO

Mechanical stimulation is prevalent within organisms, and appropriate regulation of such stimulation can significantly enhance cellular functions. Consequently, the in vitro construction and simulation of mechanical stimulation have emerged as a research hotspot in biomechanics. In recent years, a class of artificial muscles named electroactive polymers (EAPs), especially ionic EAPs, have shown promising applications in biomechanics. While several techniques utilizing ionic EAPs for cell mechanical stimulation have been reported, further research is needed to advance and enhance their practical applications. Here, we prepared a microactuator array based on ionic EAP artificial muscles for cell mechanical stimulation. As a preliminary effort, we created a 5 × 5 microactuator array on a supporting membrane by employing laser cutting. We evaluated the electro-actuation performance of the microactuators through experimental testing and numerical simulations, affirming the potential use of the microactuator array for cell mechanical stimulation. The devised approach could inspire innovative design concepts in the development of miniaturized intelligent electronic devices, not only in biomechanics and biomimetics but also in other related fields.

2.
ACS Biomater Sci Eng ; 10(4): 2133-2142, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38451467

RESUMO

Hydrogels have gained great attention and broad applications in tissue engineering, regenerative medicine, and drug delivery due to their excellent biocompatibility and degradability. However, accurately and noninvasively characterizing the degradation process of hydrogels remains a challenge. To address this, we have developed a method using soft spring gauges (SSGs) for the in situ weighing of hydrogels. Our approach uses a simple hydrogel-based sacrificial template method to fabricate polydimethylsiloxane (PDMS) SSGs. The SSGs used in this study can characterize hydrogels with a minimum wet weight of approximately 30 mg. Through theoretical derivations, numerical simulations, and experimental characterization, we confirmed that the length change of the SSGs in a buffer solution correlates linearly with the applied hanging weights. This allows us to track and assess the solid mass change of hydrogels during degradation with high feasibility and accuracy. Additionally, we have demonstrated the potential application of SSGs for the in situ characterization of engineered tissue growth. This method represents an advanced approach for in situ hydrogel weighing, holding great promise for advancing the development of hydrogels and other biomaterials in biomedical applications.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Engenharia Tecidual/métodos , Sistemas de Liberação de Medicamentos , Engenharia
3.
Mol Genet Genomics ; 299(1): 35, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489045

RESUMO

Asthenoteratospermia is a significant cause of male infertility. FAM71D (Family with sequence similarity 71, member D), as a novel protein exclusively expressed in the testis, has been found to be associated with sperm motility. However, the association of FAM71D mutation with male infertility has yet to be examined. Here, we conducted whole-exome sequencing and identified a homozygous missense mutation c.440G > A (p. Arg147Gln) of FAM71D in an asthenoteratospermia-affected man from a consanguineous family. The FAM71D variant is extremely rare in human population genome databases and predicted to be deleterious by multiple bioinformatics tools. Semen analysis indicated decreased sperm motility and obvious morphological abnormalities in sperm cells from the FAM71D-deficient man. Immunofluorescence assays revealed that the identified FAM71D mutation had an important influence on the assembly of sperm structure-related proteins. Furthermore, intra-cytoplasmic sperm injection (ICSI) treatment performed on the infertile man with FAM71D variant achieved a satisfactory outcome. Overall, our study identified FAM71D as a novel causative gene for male infertility with asthenoteratospermia, for which ICSI treatment may be suggested to acquire good prognosis. All these findings will provide effective guidance for genetic counselling and assisted reproduction treatments of asthenoteratospermia-affected subjects.


Assuntos
Infertilidade Masculina , Sêmen , Masculino , Humanos , Motilidade dos Espermatozoides , Espermatozoides , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Testículo/metabolismo , Mutação
4.
IEEE Trans Image Process ; 33: 825-839, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38231817

RESUMO

Scene text spotting is a challenging task, especially for inverse-like scene text, which has complex layouts, e.g., mirrored, symmetrical, or retro-flexed. In this paper, we propose a unified end-to-end trainable inverse-like antagonistic text spotting framework dubbed IATS, which can effectively spot inverse-like scene texts without sacrificing general ones. Specifically, we propose an innovative reading-order estimation module (REM) that extracts reading-order information from the initial text boundary generated by an initial boundary module (IBM). To optimize and train REM, we propose a joint reading-order estimation loss ( LRE ) consisting of a classification loss, an orthogonality loss, and a distribution loss. With the help of IBM, we can divide the initial text boundary into two symmetric control points and iteratively refine the new text boundary using a lightweight boundary refinement module (BRM) for adapting to various shapes and scales. To alleviate the incompatibility between text detection and recognition, we propose a dynamic sampling module (DSM) with a thin-plate spline that can dynamically sample appropriate features for recognition in the detected text region. Without extra supervision, the DSM can proactively learn to sample appropriate features for text recognition through the gradient returned by the recognition module. Extensive experiments on both challenging scene text and inverse-like scene text datasets demonstrate that our method achieves superior performance both on irregular and inverse-like text spotting.

5.
Nanotechnology ; 35(18)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38271722

RESUMO

The lack of low-cost methods to synthesize large-area graphene-based materials is still an important factor that limits the practical application of graphene devices. Herein, we present a facile method for producing large-area graphene oxide-metal (GO-M) films, which are size controllable and transferable. The sensor constructed using the GO-M film exhibited humidity sensitivity while being unaffected by pressure. The relationship between the sensor's resistance and relative humidity followed an exponential trend. The GO-Mg sensor was the most sensitive among all the tested sensors. The facile synthesis of GO-M films will accelerate the widespread utilization of graphene-based materials.

6.
Drug Dev Res ; 85(1): e22131, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37943623

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has attracted lots of attention in preventing the clearance of plasma low-density lipoprotein cholesterol (LDL-C). PCSK9 inhibitors are developed to primarily reduce the cardiovascular risk by lowering LDL-C level. Recently, a number of pleiotropic extrahepatic functions of PCSK9 beyond the regulation of cholesterol metabolism, particularly its effects on central nervous system (CNS) diseases have been increasingly identified. Emerging clinical evidence have revealed that PCSK9 may play a significant role in neurocognition, depression, Alzheimer's disease, and stroke. The focus of this review is to elucidate the functions of PCSK9 and highlight the effects of PCSK9 in CNS diseases, with the aim of identifying the potential risks that may arise from low PCSK9 level (variant or inhibitor) in the clinical practice.


Assuntos
Doenças do Sistema Nervoso Central , Pró-Proteína Convertase 9 , Humanos , Pró-Proteína Convertase 9/metabolismo , LDL-Colesterol/metabolismo , Subtilisinas , Doenças do Sistema Nervoso Central/tratamento farmacológico
7.
Front Endocrinol (Lausanne) ; 14: 1279058, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152129

RESUMO

Objective: To assess the causal effect of type 2 diabetes mellitus (T2DM) on male infertility (MI) and erectile dysfunction (ED) by Mendelian randomization (MR) analysis. Methods: Data for T2DM, MI, and ED were obtained from genome-wide association studies (GWAS) involving 298, 957, 73, 479, and 223, 805 Europeans, respectively. We performed univariate MR analysis using MR Egger, Weighted median (WM) and Inverse variance weighted (IVW) methods to assess causal effects among the three. Through the Genotype Tissue Expression (GTEx) database, single-nucleotide polymorphisms (SNPs) that affect the expression levels of T2DM-related genes were located using expression quantitative trait loci (eQTL). Results: MR analysis showed a significant causal relationship between T2DM and ED (WM, OR: 1.180, 95%CI: 1.010-1.378, P = 0.037; IVW, OR: 1.190, 95%CI: 1.084-1.300, P < 0.001). There is also a significant causal relationship between T2DM and MI (MR Egger, OR: 0.549, 95%CI: 0.317-0.952, P = 0.037; WM, OR: 0.593, 95%CI: 0.400, P = 0.010; IVW, OR: 0.767, 95%CI: 0.600-0.980, P = 0.034). ED may not cause MI (P > 0.05). We also found that rs6585827 corresponding to the PLEKHA1 gene associated with T2DM is an eQTL variant affecting the expression of this gene. Conclusion: T2DM has a direct causal effect on ED and MI. The level of PLEKHA1 expression suppressed by rs6585827 is potentially associated with a lower risk of T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Disfunção Erétil , Infertilidade Masculina , Humanos , Masculino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Infertilidade Masculina/genética , Bases de Dados Factuais
9.
Int J Mol Sci ; 24(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37446203

RESUMO

Plant height, petiole length, and the angle of the leaf petiole and branch angles are crucial traits determining plant architecture and yield in soybean (Glycine max L.). Here, we characterized a soybean mutant with super-short petioles (SSP) and enlarged petiole angles (named Gmssp) through phenotypic observation, anatomical structure analysis, and bulk sequencing analysis. To identify the gene responsible for the Gmssp mutant phenotype, we established a pipeline involving bulk sequencing, variant calling, functional annotation by SnpEFF (v4.0e) software, and Integrative Genomics Viewer analysis, and we initially identified Glyma.11G026400, encoding a homolog of Anaphase-promoting complex subunit 8 (APC8). Another mutant, t7, with a large deletion of many genes including Glyma.11G026400, has super-short petioles and an enlarged petiole angle, similar to the Gmssp phenotype. Characterization of the t7 mutant together with quantitative trait locus mapping and allelic variation analysis confirmed Glyma.11G026400 as the gene involved in the Gmssp phenotype. In Gmssp, a 4 bp deletion in Glyma.11G026400 leads to a 380 aa truncated protein due to a premature stop codon. The dysfunction or absence of Glyma.11G026400 caused severe defects in morphology, anatomical structure, and physiological traits. Transcriptome analysis and weighted gene co-expression network analysis revealed multiple pathways likely involved in these phenotypes, including ubiquitin-mediated proteolysis and gibberellin-mediated pathways. Our results demonstrate that dysfunction of Glyma.11G026400 leads to diverse functional consequences in different tissues, indicating that this APC8 homolog plays key roles in cell differentiation and elongation in a tissue-specific manner. Deciphering the molecular control of petiole length and angle enriches our knowledge of the molecular network regulating plant architecture in soybean and should facilitate the breeding of high-yielding soybean cultivars with compact plant architecture.


Assuntos
Anáfase , Glycine max , Glycine max/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Fenótipo
10.
Cancers (Basel) ; 15(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37190330

RESUMO

(1) Background: Biopsies are the gold standard for the diagnosis of musculoskeletal tumors. In this study, we aimed to explore whether indocyanine green near-infrared fluorescence imaging can assist in the biopsy of bone and soft tissue tumors and improve the success rate of biopsy. (2) Method: We recruited patients with clinically considered bone and soft tissue tumors and planned biopsies. In the test group, indocyanine green (0.3 mg/kg) was injected. After identifying the lesion, a near-infrared fluorescence camera system was used to verify the ex vivo specimens of the biopsy in real time. If the biopsy specimens were not developed, we assumed that we failed to acquire lesions, so the needle track and needle position were adjusted for the supplementary biopsy, and then real-time imaging was performed again. Finally, we conducted a pathological examination. In the control group, normal biopsy was performed. (3) Results: The total diagnosis rate of musculoskeletal tumors in the test group was 94.92% (56/59) and that in the control group was 82.36% (42/51). In the test group, 14 cases were not developed, as seen from real-time fluorescence in the core biopsy, and then underwent the supplementary biopsy after changing the puncture direction and the location of the needle channel immediately, of which 7 cases showed new fluorescence. (4) Conclusions: Using the near-infrared fluorescence real-time development technique to assist the biopsy of musculoskeletal tumors may improve the accuracy of core biopsy and help to avoid missed diagnoses, especially for some selected tumors.

11.
J Surg Oncol ; 128(4): 612-627, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37178368

RESUMO

BACKGROUND AND OBJECTIVES: Negative surgical margins are significant in improving patient outcomes. However, surgeons can only rely on visual and tactile information to identify tumor margins intraoperatively. We hypothesized that intraoperative fluorescence imaging with indocyanine green (ICG) could serve as an assistive technology to evaluate surgical margins and guide surgery in bone and soft tissue tumor surgery. METHODS: Seventy patients with bone and soft tissue tumors were enrolled in this prospective, non-randomized, single-arm feasibility study. All patients received intravenous indocyanine green (0.5 mg/kg) before surgery. Near-infrared (NIR) imaging was performed on in situ tumors, wounds, and ex vivo specimens. RESULTS: 60/70 tumors were fluorescent at NIR imaging. The final surgical margins were positive in 2/55 cases, including 1/40 of the sarcomas. Surgical decisions were changed in 19 cases by NIR imaging, and in 7/19 cases final pathology demonstrated margins were improved. Fluorescence analysis showed that the tumor-to-background ratio (TBR) of primary malignant tumors was higher than that of benign, borderline, metastatic, and tumors ≥5 cm in size had higher TBR than those <5 cm. CONCLUSIONS: ICG fluorescence imaging may be a beneficial technique to assist in surgical decision making and improving surgical margins in bone and soft tissue tumor surgery.


Assuntos
Verde de Indocianina , Neoplasias de Tecidos Moles , Humanos , Margens de Excisão , Estudos Prospectivos , Imagem Óptica/métodos , Neoplasias de Tecidos Moles/diagnóstico por imagem , Neoplasias de Tecidos Moles/cirurgia , Tomada de Decisões
12.
Water Res ; 239: 120035, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37172373

RESUMO

In situ chemical oxidation (ISCO) is widely used as an efficient remediation technology for groundwater pollution. However, quantitative studies of its reactive remediation process under coupled thermal desorption technology are scarce. Based on laboratory experiments and site remediation, the chemical oxidation remediation reaction process was quantified, and the apparent reaction equation of the ISCO process was constructed. And then, a numerical model coupled with Hydraulic-Thermal-Chemical (HTC) fields was built to quantitatively describe the remediation process of an actual contaminated site. The simulation results fit well with the site monitoring data, and the results indicated that thermal desorption strengthens the ISCO remediation effect. In addition, the HTC model is expanded to build a conceptual and numerical model of a coupled remediation system, including heating and remediation wells. The results showed that high-temperature conditions enhance the activity of remediation chemicals and increase the rate of remediation reaction to obtain a better remediation effect. The heating wells increase the regional temperature, accelerating the diffusion of pollutants and remediation chemicals, and promoting adequate contact and reaction. Based on this crucial mechanism, thermal desorption coupled with ISCO technology can significantly improve remediation efficiency, shorten the remediation cycle, and precisely control agent delivery with the help of numerical simulation to avoid secondary contamination.


Assuntos
Recuperação e Remediação Ambiental , Água Subterrânea , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Oxirredução , Poluição Ambiental , Modelos Químicos
13.
Artigo em Inglês | MEDLINE | ID: mdl-37022078

RESUMO

Transformers are more and more popular in computer vision, which treat an image as a sequence of patches and learn robust global features from the sequence. However, pure transformers are not entirely suitable for vehicle re-identification because vehicle re-identification requires both robust global features and discriminative local features. For that, a graph interactive transformer (GiT) is proposed in this paper. In the macro view, a list of GiT blocks are stacked to build a vehicle re-identification model, in where graphs are to extract discriminative local features within patches and transformers are to extract robust global features among patches. In the micro view, graphs and transformers are in an interactive status, bringing effective cooperation between local and global features. Specifically, one current graph is embedded after the former level's graph and transformer, while the current transform is embedded after the current graph and the former level's transformer. In addition to the interaction between graphs and transforms, the graph is a newly-designed local correction graph, which learns discriminative local features within a patch by exploring nodes' relationships. Extensive experiments on three large-scale vehicle re-identification datasets demonstrate that our GiT method is superior to state-of-the-art vehicle re-identification approaches.

14.
Biochem Pharmacol ; 212: 115554, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37080437

RESUMO

BACKGROUND: Melanoma has become more common, and its therapeutic management has remained challenging in recent decades. The purpose of our study is to explore new prognostic therapeutic markers of melanoma and to find new therapeutic methods and therapeutic targets of novel drugs, which have great significance. METHOD: First, the arachidonate 5-lipoxygenase (ALOX5) gene associated with both autophagy and ferroptosis was identified by R version 4.2.0. We used human melanoma and para-cancer tissues, human melanoma cell lines, and melanoma-bearing mouse tissues. We used qRT-PCR, Western blotting, immunohistochemistry, immunofluorescence staining, CCK-8, iron ion assay, GSH assay, and MDA assay. In vivo, the ferroptosis activation and antitumor effects of recombinant human ALOX5 protein were evaluated using a xenograft model. RESULT: We report that the downregulation of ALOX5 in melanoma is positively correlated with the prognosis of patients and is an independent prognostic factor. Elevated ALOX5 contributes to autophagy and ferroptosis in vitro and in vivo. At the same time, inhibition of autophagy can reduce ferroptosis enhanced by ALOX5, and autophagy and ALOX5 have a synergistic effect. The results of the mechanistic study showed that the increase in ALOX5 could activate the AMPK/mTOR pathway and inhibit GPX4 expression, promoting the occurrence of autophagy-dependent ferroptosis, while the decrease in p-AMPK/AMPK inhibited the occurrence of ferroptosis. CONCLUSION: ALOX5 deficiency was resistant to autophagy and ferroptosis by inhibiting the AMPK/mTOR pathway. Therefore, it can provide new targets and methods for melanoma drug development.


Assuntos
Ferroptose , Melanoma , Humanos , Camundongos , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Transdução de Sinais , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/metabolismo , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Autofagia
15.
J Exp Bot ; 74(14): 4014-4030, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37074373

RESUMO

Yellow-green variegation leaf phenotype adds more value to ornamental plants, but it is regarded as an undesirable trait in crop plants, affecting their yields. Until recently, the underlying mechanism regulating the yellow-green variegation phenotype has remained largely unexplored in soybean. In the present study, we indentified four Glycine max leaf yellow/green variegation mutants, Gmvar1, Gmvar2, Gmvar3, and Gmvar4, from artificial mutagenesis populations. Map-based cloning, together with the allelic identification test and CRISPR-based gene knockout, proved that mutated GmCS1 controls yellow-green variegation phenotype of the Gmvar mutants. GmCS1 encodes a chorismate synthase in soybean. The content of Phe, Tyr, and Trp were dramatically decreased in Gmcs1 mutants. Exogenous supply of three aromatic amino acid mixtures, or only Phe to Gmvar mutants, leads to recovery of the mutant phenotype. The various biological processes and signalling pathways related to metabolism and biosynthesis were altered in Gmvar mutants. Collectively, our findings provide new insights about the molecular regulatory network of yellow-green variegation leaf phenotype in soybean.


Assuntos
Cloroplastos , Glycine max , Glycine max/genética , Cloroplastos/metabolismo , Mutação , Fenótipo , Folhas de Planta/metabolismo
16.
Sci Total Environ ; 875: 162632, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889411

RESUMO

The composite of phase change material (PCM) and high-viscosity modified asphalt (HVMA) is expected as a new material regulating the temperature of high-performance pavements, thereby ameliorating the urban heat island effect. This study focused on evaluating the roles of two kinds of PCMs, i.e. paraffin/expanded graphite/high-density polyethylene composite material (PHDP) and polyethylene glycol (PEG), on a series of performances of HVMA. Fluorescence microscopy observations, physical rheological properties tests and indoor temperature regulating tests were conducted to determine the morphological, physical, rheological and temperature regulating performances of PHDP/HVMA or PEG/HVMA composites with various PCM contents prepared by fusion blending. Fluorescence microscopy test results revealed that the PHDP and PEG could be uniformly distributed in HVMA, but their distribution size and morphology were obviously different. Physical test results showed an increase in the penetration values of both PHDP/HVMA and PEG/HVMA compared to the HVMA without PCM. Their softening points did not change significantly with increasing PCM content due to the presence of a high-content of polymeric spatial reticulation. Ductility test reflected that the low-temperature properties of PHDP/HVMA were improved. However, the ductility of PEG/HVMA was much reduced due to the presence of large size PEG particles especially at 15 % PEG content. Rheological results from the recovery percent and non-recoverable creep compliance at 64 °C confirmed that the PHDP/HVMA and PEG/HVMA had excellent high-temperature rutting resistance regardless of PCM contents. Notably, the phase angle results reflected that the PHDP/HVMA was more viscous at 5-30 °C and more elastic at 30-60 °C. By contrast, PEG/HVMA was more elastic at the whole temperature range of 5-60 °C. Lastly but not least, compared to HVMA without PCM, the temperature regulating effect was 4 °C during heating of PHDP/HVMA containing 4 % PHDP and PEG/HVMA containing 15 % PEG, and their delay time were 456 s and 1240 s, respectively.

17.
Theor Appl Genet ; 136(3): 56, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36912958

RESUMO

KEY MESSAGE: A novel splice-site mutation in the P. vulgarisgene for TETRAKETIDE α-PYRONE REDUCTASE 2 impairs male fertility, and parthenocarpic pod development can be improved by external application of IAA. Snap bean (Phaseolus vulgaris L.) is an important vegetable crop in many parts of the world, and the main edible part is the fresh pod. Here, we report the characterization of the genic male sterility (ms-2) mutant in common bean. Loss of function of MS-2 accelerates degradation of the tapetum, resulting in a complete male sterility. Through fine-mapping, co-segregation, and re-sequencing analysis, we identified Phvul.003G032100, which encodes the TETRAKETIDE α-PYRONE REDUCTASE 2 (PvTKPR2) protein in common bean, as the causal gene for MS-2. PvTKPR2 is predominantly expressed at the early stages of flower development. A novel 7-bp (+ 6028 bp to + 6034 bp) deletion mutation spans the splice site between the fourth intron and fifth exon, leading to a 9-bp deletion in transcribed mRNA and a 3-amino acid (G210M211V212) deletion in the protein coding sequence of the PvTKPR2ms-2 gene. The 3-D structural changes in the protein due to the mutation may impair the activities of NAD-dependent epimerase/dehydratase and the NAD(P)-binding domains of PvTKPR2ms-2 protein. The ms-2 mutant plants produce many small parthenocarpic pods, and the size of the pods can be doubled by external application of 2 mM indole-3-acetic acid (IAA). Our results demonstrate that a novel mutation in PvTKPR2 impairs male fertility through premature degradation of the tapetum.


Assuntos
Phaseolus , Phaseolus/genética , Pareamento de Bases , NAD/genética , Pironas , Oxirredutases/genética , Fertilidade
18.
Sci Total Environ ; 867: 161368, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36621512

RESUMO

Seawater intrusion is a global coastal environmental issue of great concern and significantly impacts the regional biogeochemical environment and material cycles, including nitrogen cycling. To reveal the mechanism of seawater intrusion altering nitrogen cycling patterns through hydrodynamic behavior and biochemical reactions, the Bayesian mixing model (δ15N-NO3- and δ18O-NO3-) and 16S rDNA gene amplicon sequencing are used to establish nitrogen cycling pathways and microbial functional network. The results show that the nitrate in the coastal groundwater is from manure and septic waste (M&S, over 44 %), soil organic nitrogen (SON, over 20 %), and nitrogen fertilizer (FN, over 16 %). The hydrological interaction has promoted the coupling between material cycling and microbial community in the coastal groundwater systems. Among them, precipitation infiltration has caused the gradual decrease of specific microbes along the flow direction, such as Lactobacillus, Acinetobacter, Bifidobacterium, etc. And seawater intrusion has caused the mutations of specific microbes (Planktomarina, Clade_Ia, Wenyingzhuangia, Glaciecola, etc.) and convergence of microbial community at the salt-freshwater interface in the aquifer. In the coastal intruded aquifer systems, the nitrogen cycling pattern can be divided into oxidation and reduction processes. The oxidation process involves the enhancement of nitrification while the weakening of denitrification and anammox with the increase of aquifer depth. The reduction process consists of the enhancement of denitrification and anammox while the erosion of nitrification and ammonification with increased seawater intrusion. In addition, seawater intrusion can mitigate nitrate contamination by promoting denitrification and anammox in coastal areas.


Assuntos
Água Subterrânea , Nitratos , Nitratos/análise , Teorema de Bayes , Hidrodinâmica , Ciclo do Nitrogênio , Água do Mar , Nitrogênio/análise , Isótopos , Água Subterrânea/microbiologia , Monitoramento Ambiental
19.
IEEE Trans Neural Netw Learn Syst ; 34(4): 1852-1863, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31995502

RESUMO

The point process is a solid framework to model sequential data, such as videos, by exploring the underlying relevance. As a challenging problem for high-level video understanding, weakly supervised action recognition and localization in untrimmed videos have attracted intensive research attention. Knowledge transfer by leveraging the publicly available trimmed videos as external guidance is a promising attempt to make up for the coarse-grained video-level annotation and improve the generalization performance. However, unconstrained knowledge transfer may bring about irrelevant noise and jeopardize the learning model. This article proposes a novel adaptability decomposing encoder-decoder network to transfer reliable knowledge between the trimmed and untrimmed videos for action recognition and localization by bidirectional point process modeling, given only video-level annotations. By decomposing the original features into the domain-adaptable and domain-specific ones based on their adaptability, trimmed-untrimmed knowledge transfer can be safely confined within a more coherent subspace. An encoder-decoder-based structure is carefully designed and jointly optimized to facilitate effective action classification and temporal localization. Extensive experiments are conducted on two benchmark data sets (i.e., THUMOS14 and ActivityNet1.3), and the experimental results clearly corroborate the efficacy of our method.

20.
IEEE Trans Pattern Anal Mach Intell ; 45(3): 2736-2750, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35594227

RESUMO

Arbitrary shape text detection is a challenging task due to the significantly varied sizes and aspect ratios, arbitrary orientations or shapes, inaccurate annotations, etc. Due to the scalability of pixel-level prediction, segmentation-based methods can adapt to various shape texts and hence attracted considerable attention recently. However, accurate pixel-level annotations of texts are formidable, and the existing datasets for scene text detection only provide coarse-grained boundary annotations. Consequently, numerous misclassified text pixels or background pixels inside annotations always exist, degrading the performance of segmentation-based text detection methods. Generally speaking, whether a pixel belongs to text or not is highly related to the distance with the adjacent annotation boundary. With this observation, in this paper, we propose an innovative and robust segmentation-based detection method via probability maps for accurately detecting text instances. To be concrete, we adopt a Sigmoid Alpha Function (SAF) to transfer the distances between boundaries and their inside pixels to a probability map. However, one probability map can not cover complex probability distributions well because of the uncertainty of coarse-grained text boundary annotations. Therefore, we adopt a group of probability maps computed by a series of Sigmoid Alpha Functions to describe the possible probability distributions. In addition, we propose an iterative model to learn to predict and assimilate probability maps for providing enough information to reconstruct text instances. Finally, simple region growth algorithms are adopted to aggregate probability maps to complete text instances. Experimental results demonstrate that our method achieves state-of-the-art performance in terms of detection accuracy on several benchmarks. Notably, our method with Watershed Algorithm as post-processing achieves the best F-measure on Total-Text (88.79%), CTW1500 (85.75%), and MSRA-TD500 (88.93%). Besides, our method achieves promising performance on multi-oriented datasets (ICDAR2015) and multilingual datasets (ICDAR2017-MLT). Code is available at: https://github.com/GXYM/TextPMs.

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