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1.
Appl Opt ; 63(3): 823-830, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294397

RESUMO

Silicon nanostructure colors have rapidly developed in recent years, offering high resolution and a broad color gamut that traditional pigments cannot achieve. The reflected colors of metasurfaces are determined by the geometric structure of the unit cell and the refractive index matching layer parameters. It is evident that the design of specific colors involves numerous parameters, making it challenging to achieve through conventional calculations. Therefore, the tandem network instead of conventional electromagnetic simulation is natural. The forward part of the network incorporates feature cross terms to improve accuracy, enabling high-precision predictions of structural colors based on structural parameters. The average color difference between the predicted and actual color values in the L,a,b color space is 1.38. The network has been proven to accurately predict the refractive index and height of the refractive index matching layer during the dynamic tuning process. Additionally, the issue of the inverse network converging to incorrect solutions was addressed by leveraging the characteristics of the activation function. The results show that the color difference between the colors designed by the inverse network compared to the actual colors in the L,a,b color spaces is only 2.22, which meets the requirements for commercial applications.

2.
JAMA Neurol ; 81(1): 81-82, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37983040

RESUMO

This case report describes reversible cortical and basal ganglia lesions in late-onset methylmalonic aciduria in a man in his mid-40s.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Humanos , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Gânglios da Base/diagnóstico por imagem
3.
Materials (Basel) ; 16(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37959656

RESUMO

This study investigates the microstructures and deformation mechanism of hetero-structured pure Ti under different high strain rates (500 s-1, 1000 s-1, 2000 s-1). It has been observed that, in samples subjected to deformation, the changes in texture are minimal and the rise in temperature is relatively low. Therefore, the influence of these two factors on the deformation mechanism can be disregarded. As the strain rate increases, the dominance of dislocation slip decreases while deformation twinning becomes more prominent. Notably, at a strain rate of 2000 s-1, nanoscale twin lamellae are activated within the grain with a size of 500 nm, which is a rarely observed phenomenon in pure Ti. Additionally, martensitic phase transformation has also been identified. In order to establish a correlation between the stress required for twinning and the grain size, a modified Hall-Petch model is proposed, with the obtained value of Ktwin serving as an effective metric for this relationship. These findings greatly enhance our understanding of the mechanical responses of Ti and broaden the potential applications of Ti in dynamic deformation scenarios.

4.
Sensors (Basel) ; 23(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37837071

RESUMO

Road defect detection is a crucial aspect of road maintenance projects, but traditional manual methods are time-consuming, labor-intensive, and lack accuracy. Leveraging deep learning frameworks for object detection offers a promising solution to these challenges. However, the complexity of backgrounds, low resolution, and similarity of cracks make detecting road cracks with high accuracy challenging. To address these issues, a novel road crack detection algorithm, termed Road Defect Detection YOLOv5 (RDD-YOLOv5), was proposed. Firstly, a model was proposed to integrate the transformer structure and explicit vision center to capture the long-distance dependency and aggregate key characteristics. Additionally, the Sigmoid-weighted linear activations in YOLOv5 were replaced with the Gaussian Error Linear Units to enhance the model's nonlinear fitting capability. To evaluate the algorithm's performance, a UAV flight platform was constructed, and experimental freebies were provided to boost inspection efficiency. The experimental results demonstrate the effectiveness of RDD-YOLOv5, achieving a mean average precision of 91.48%, surpassing the original YOLOv5 by 2.5%. The proposed model proves its ability to accurately identify road cracks, even under challenging and complex traffic backgrounds. This advancement in road crack detection technology has significant implications for improving road maintenance and safety.

5.
Ann Hematol ; 102(9): 2365-2373, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37453949

RESUMO

Many clinical features, besides cytogenetic and molecular abnormalities, can affect the prognosis of the patients with acute myeloid leukemia (AML). Within this context it remains unclear if and how platelet counts affect the outcome of AML patients. In the present study, we examined the platelet counts at diagnosis in 633 newly diagnosed adult patients with AML from January 2010 to April 2021, and divided the cases into the group with low level of platelet counts (≤30×109/L, n=316) and high level of platelet counts (>30×109/L, n=317) according to the median platelet counts. We then validated the prognostic significance and potential mechanism of platelet counts on the relevance of spectral features for diagnostic risk stratification, initial induction therapy response, treatment effect maintenance, long-term survival, leukemia stem cells (LSCs) proportion, immunomodulatory cytokines level and immune cell subsets proportion. The results suggested that AML patients with a high level of platelet counts at diagnosis were associated with a high-risk molecular cytogenetic stratification, low complete remission (CR) rate, poor leukemia free survival (LFS), high proportion of LSCs, high level of transforming growth factor-ß (TGF-ß) and interleukin-1ß (IL-1ß), high proportion of regulatory T cells (Tregs) and monocytic myeloid-derived suppressor cells (M-MDSCs). It was demonstrated that platelet might be an unfavorable prognostic biomarker and was associated with LSCs and immunomodulatory cytokines as well as immune cell subsets in AML.


Assuntos
Citocinas , Leucemia Mieloide Aguda , Adulto , Humanos , Prognóstico , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Biomarcadores , Células-Tronco
6.
J Org Chem ; 88(14): 9811-9822, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37401110

RESUMO

Catalytic selective annulation of 2H-azirines constitutes a general and modular strategy for the generation of molecular complexity. By using Pd-catalyzed ring opening/heterocyclization associated with direct cleavage of C-N and C-C bonds under appropriate conditions, the formation of imidazoles is presented. Alternatively, the silver-catalyzed radical [3 + 2] cycloannulation of 2H-azirines and 1,3-dicarbonyl compounds provides highly functionalized pyrrole derivatives. Both aliphatic cyclic and acyclic diketones are tolerated with good regioselectivity. Moreover, a radical capture experiment was carried out to determine the proposed mechanism, providing support for a facile radical process.

7.
Immunogenetics ; 75(4): 395-401, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37347248

RESUMO

Wilms tumor gene 1 (WT-1 gene) is overexpressed in most patients with acute myeloid leukemia (AML) and is an indicator for minimal residual disease (MRD) monitoring, but because the WT-1 gene has relatively low specificity, further studies of the prognostic value of a combination of the WT-1 and other genes are needed. The aim of this study was to explore the prognostic value of the WT-1 gene combined with recurrent cytogenetic genes in AML. In AML, the transcript expression of the WT-1 gene was closely related to leukemic tumor burden and acted as an accurate molecular indicator for MRD detection. Most patients with low expression levels of the WT-1 gene after induction and consolidation therapy were significantly associated with favorable relapse-free survival (RFS) and overall survival (OS), but 17.6% of patients relapsed and died of primary disease. However, when analyzing the WT-1 gene combined with recurrent cytogenetic genes, none of the patients with low expression levels of the WT-1 gene and recurrent cytogenetic genes negative relapsed and died in the median follow-up time of 19 months (range: 3-94 months). Thus, the combination of the WT-1 gene and recurrent cytogenetic genes is a more accurate indicator for MRD monitoring and prognosis evaluation in AML patients.


Assuntos
Genes do Tumor de Wilms , Leucemia Mieloide Aguda , Humanos , Prognóstico , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Recidiva , Neoplasia Residual/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/patologia , Análise Citogenética
8.
Cell Rep ; 42(5): 112480, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37163375

RESUMO

The cerebellum is essential for motor control and cognitive functioning, engaging in bidirectional communication with the cerebral cortex. The common marmoset, a small non-human primate, offers unique advantages for studying cerebello-cerebral circuits. However, the marmoset cerebellum is not well described in published resources. In this study, we present a comprehensive atlas of the marmoset cerebellum comprising (1) fine-detailed anatomical atlases and surface-analysis tools of the cerebellar cortex based on ultra-high-resolution ex vivo MRI, (2) functional connectivity and gradient patterns of the cerebellar cortex revealed by awake resting-state fMRI, and (3) structural-connectivity mapping of cerebellar nuclei using high-resolution diffusion MRI tractography. The atlas elucidates the anatomical details of the marmoset cerebellum, reveals distinct gradient patterns of intra-cerebellar and cerebello-cerebral functional connectivity, and maps the topological relationship of cerebellar nuclei in cerebello-cerebral circuits. As version 5 of the Marmoset Brain Mapping project, this atlas is publicly available at https://marmosetbrainmapping.org/MBMv5.html.


Assuntos
Callithrix , Cerebelo , Animais , Imageamento por Ressonância Magnética , Mapeamento Encefálico , Córtex Cerebelar/diagnóstico por imagem
10.
Environ Int ; 153: 106524, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33773143

RESUMO

BACKGROUND AND OBJECTIVE: The growing impact of the COVID-19 pandemic has heightened the urgency of identifying individuals most at risk of infection. Per- and poly-fluoroalkyl substances (PFASs) are manufactured fluorinated chemicals widely used in many industrial and household products. The objective of this case-control study was to assess the association between PFASs exposure and COVID-19 susceptibility and to elucidate the metabolic dysregulation associated with PFASs exposure in COVID-19 patients. METHODS: Total 160 subjects (80 COVID-19 patients and 80 symptom-free controls) were recruited from Shanxi and Shandong provinces, two regions heavily polluted by PFASs in China. Twelve common PFASs were quantified in both urine and serum. Urine metabolome profiling was performed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). RESULTS: In unadjusted models, the risk of COVID-19 infection was positively associated with urinary levels of perfluorooctanesulfonic acid (PFOS) (Odds ratio: 2.29 [95% CI: 1.52-3.22]), perfluorooctanoic acid (PFOA) (2.91, [1.95-4.83], and total PFASs (∑ (12) PFASs) (3.31, [2.05-4.65]). After controlling for age, sex, body mass index (BMI), comorbidities, and urine albumin-to-creatinine ratio (UACR), the associations remained statistically significant (Adjusted odds ratio of 1.94 [95% CI: 1.39-2.96] for PFOS, 2.73 [1.71-4.55] for PFOA, and 2.82 [1.97-3.51] for ∑ (12) PFASs). Urine metabolome-PFASs association analysis revealed that 59% of PFASs-associated urinary endogenous metabolites in COVID-19 patients were identified to be produced or largely regulated by mitochondrial function. In addition, the increase of PFASs exposure was associated with the accumulation of key metabolites in kynurenine metabolism, which are involved in immune responses (Combined ß coefficient of 0.60 [95% CI: 0.25-0.95, P = 0.001]). Moreover, alternations in PFASs-associated metabolites in mitochondrial and kynurenine metabolism were also correlated with clinical lab biomarkers for mitochondrial function (serum growth/differentiation factor-15) and immune activity (lymphocyte percentage), respectively. CONCLUSION: Elevated exposure to PFASs was independently associated with an increased risk of COVID-19 infection. PFASs-associated metabolites were implicated in mitochondrial function and immune activity. Larger studies are needed to confirm our findings and further understand the underlying mechanisms of PFASs exposure in the pathogenesis of SARS-CoV2 infection.


Assuntos
Ácidos Alcanossulfônicos , COVID-19 , Poluentes Ambientais , Fluorocarbonos , Ácidos Alcanossulfônicos/toxicidade , Caprilatos/toxicidade , Estudos de Casos e Controles , China/epidemiologia , Cromatografia Líquida , Poluentes Ambientais/toxicidade , Fluorocarbonos/análise , Fluorocarbonos/toxicidade , Humanos , Pandemias , RNA Viral , SARS-CoV-2 , Espectrometria de Massas em Tandem
11.
Environ Toxicol Pharmacol ; 60: 202-208, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29738946

RESUMO

Gut microbiome dysbiosis plays a profound role in the pathogenesis of obesity and tributyltin (TBT) has been found as an environmental obesogen. However, whether TBT could disturb gut microbiome and the relationship between obesity induced by TBT exposure and alteration in gut microbiota are still unknown. In order to assess the association between them, mice were exposed to TBTCl (50 µg kg-1) once every three days from postnatal days (PNDs) 24 to 54. The results demonstrated that TBT exposure resulted in increased body weight gain, lager visceral fat accumulation and dyslipidemia in male mice on PND 84. Correspondingly, 16S rRNA gene sequencing revealed that TBT treatment decreased gut microbial species and perturbed the microbiome composition in mice. Furthermore, Pearson's corelation coefficient analysis showed a significantly negative correlation between the body weight and the alpha diversity of gut microbiome. These results suggested that TBT exposure could induce gut microbiome dysbiosis in mice, which might contribute to the obesity pathogenesis.


Assuntos
Bactérias/classificação , Disbiose/induzido quimicamente , Dislipidemias/induzido quimicamente , Obesidade/induzido quimicamente , Compostos de Trialquitina/toxicidade , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Disbiose/microbiologia , Dislipidemias/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Obesidade/microbiologia , RNA Bacteriano , RNA Ribossômico 16S/genética , Análise de Sequência de RNA
12.
Environ Toxicol ; 33(7): 752-758, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29675927

RESUMO

Tributyltin (TBT), a proven environmental obesogen, functions as a nanomolar agonist of the peroxisome proliferator activated receptor-γ (PPARγ). However, the adverse effects of TBT on metabolism are incompletely understood. In this study, male ICR mice were administered TBT (5 and 50 µg·kg-1 ) by an intraperitoneal injection once every 3 days for 30 days from 28 days of age and bred for another 30 days after the last administration of TBT. We analyzed the effects of these exposures on the fat depot weights, serum lipid profile, serum leptin and adiponectin, hepatic lipid accumulation, and activity of AKT in the liver and skeletal muscle isolated from mice 8 mins after receiving an insulin injection. Pubertal exposure to TBTCl resulted in a higher body weight, increased epididymal and liver fat accumulation, hyperlipidemia, an elevated low-density lipoprotein/high-density lipoprotein ratio, serum adiponectin deficiency, worse glucose tolerance, and lower insulin-dependent AKT phosphorylation in the liver and muscle in mice. These results showed that TBT exposure induced peripheral insulin resistance and metabolic syndrome in mice.


Assuntos
Adiponectina/sangue , Síndrome Metabólica/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Compostos de Trialquitina/toxicidade , Animais , Fígado Gorduroso/etiologia , Teste de Tolerância a Glucose , Insulina/farmacologia , Leptina/sangue , Lipídeos/sangue , Masculino , Síndrome Metabólica/veterinária , Camundongos , Camundongos Endogâmicos ICR , PPAR gama/agonistas , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos
13.
Sensors (Basel) ; 17(11)2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29077017

RESUMO

In wireless sensor and actor networks, when an event is detected, the sensor node needs to transmit an event report to inform the actor. Since the actor moves in the network to execute missions, its location is always unavailable to the sensor nodes. A popular solution is the search strategy that can forward the data to a node without its location information. However, most existing works have not considered the mobility of the node, and thus generate significant energy consumption or transmission delay. In this paper, we propose the trail-based search (TS) strategy that takes advantage of actor's mobility to improve the search efficiency. The main idea of TS is that, when the actor moves in the network, it can leave its trail composed of continuous footprints. The search packet with the event report is transmitted in the network to search the actor or its footprints. Once an effective footprint is discovered, the packet will be forwarded along the trail until it is received by the actor. Moreover, we derive the condition to guarantee the trail connectivity, and propose the redundancy reduction scheme based on TS (TS-R) to reduce nontrivial transmission redundancy that is generated by the trail. The theoretical and numerical analysis is provided to prove the efficiency of TS. Compared with the well-known expanding ring search (ERS), TS significantly reduces the energy consumption and search delay.

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