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1.
J Xray Sci Technol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38995762

RESUMO

BACKGROUND: Due to the incomplete projection data collected by limited-angle computed tomography (CT), severe artifacts are present in the reconstructed image. Classical regularization methods such as total variation (TV) minimization, ℓ0 minimization, are unable to suppress artifacts at the edges perfectly. Most existing regularization methods are single-objective optimization approaches, stemming from scalarization methods for multiobjective optimization problems (MOP). OBJECTIVE: To further suppress the artifacts and effectively preserve the edge structures of the reconstructed image. METHOD: This study presents a multiobjective optimization model incorporates both data fidelity term and ℓ0-norm of the image gradient as objective functions. It employs an iterative approach different from traditional scalarization methods, using the maximization of structural similarity (SSIM) values to guide optimization rather than minimizing the objective function.The iterative method involves two steps, firstly, simultaneous algebraic reconstruction technique (SART) optimizes the data fidelity term using SSIM and the Simulated Annealing (SA) algorithm for guidance. The degradation solution is accepted in the form of probability, and guided image filtering (GIF) is introduced to further preserve the image edge when the degradation solution is rejected. Secondly, the result from the first step is integrated into the second objective function as a constraint, we use ℓ0 minimization to optimize ℓ0-norm of the image gradient, and the SSIM, SA algorithm and GIF are introduced to guide optimization process by improving SSIM value like the first step. RESULTS: With visual inspection, the peak signal-to-noise ratio (PSNR), root mean square error (RMSE), and SSIM values indicate that our approach outperforms other traditional methods. CONCLUSIONS: The experiments demonstrate the effectiveness of our method and its superiority over other classical methods in artifact suppression and edge detail restoration.

2.
Sci Rep ; 14(1): 5540, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448568

RESUMO

Social integration, a huge issue triggered by migration, leads to potential social fragmentation and confrontation. Focusing on the precise enhancement of "inner" subjective social integration is the ultimate urbanization solution to enhance people-centered well-being and promote full social integration. This article used data from the China Migrants Dynamic Survey 2017 (CMDS 2017) to reveal the spatial patterns and mechanisms of subjective social integration in Chinese cities. We make an innovative attempt to introduce multiscale geographically weighted regression (MGWR) to address the appropriateness of policy formulation by addressing the spatial variation in the factors. The results demonstrate that the influences on subjective social integration have a strong spatial heterogeneity in China, a vast and unevenly developed country. Expanding on the typical factors, household registration and political participation affect North China more than other regions; and housing and marriage have a greater impact in South China, especially in the Pearl River Delta and the Eastern Seaboard. Income, welfare, and healthcare are indiscriminately sweeping through most of China. Such a conclusion reminds the Chinese government that it needs to consider not only addressing some of the national constraints to subjective social integration but also imposing precise, site-specific changes for different regions.


Assuntos
Migrantes , Humanos , Cidades , Urbanização , Povo Asiático , Integração Social
3.
Phys Med Biol ; 69(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38518384

RESUMO

Objective. Limited-angle x-ray computed tomography (CT) is a typical ill-posed inverse problem, leading to artifacts in the reconstructed image due to the incomplete projection data. Most iteration CT reconstruction methods involve optimization for a single object. This paper explores a multi-objective optimization model and an interactive method based on multi-objective optimization to suppress the artifacts of limited-angle CT.Approach. The model includes two objective functions on the dual domain within the data consistency constraint. In the interactive method, the structural similarity index measure (SSIM) is regarded as the value function of the decision maker (DM) firstly. Secondly, the DM arranges the objective functions of the multi-objective optimization model to be optimized according to their absolute importance. Finally, the SSIM and the simulated annealing (SA) method help the DM choose the desirable reconstruction image by improving the SSIM value during the iteration process.Main results. Simulation and real data experiments demonstrate that the artifacts can be suppressed by the proposed method, and the results were superior to those reconstructed by the other three reconstruction methods in preserving the edge structure of the image.Significance. The proposed interactive method based on multi-objective optimization shows some potential advantages over classical single object optimization methods.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Artefatos , Imagens de Fantasmas , Humanos , Algoritmos
4.
Acad Radiol ; 31(5): 1792-1798, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38307790

RESUMO

RATIONALE AND OBJECTIVES: To identify the risk factors for contrast media (CM) extravasation and provide effective guidance for reducing its incidence. MATERIALS AND METHODS: We observed adult inpatients (n = 38 281) who underwent intravenous contrast-enhanced computed tomography between January 1, 2018, and December 31, 2022. Risk factors for CM extravasation were evaluated using univariate and multivariate logistic regression. RESULTS: Among the 38 281 inpatients who underwent enhanced computed tomography angiography, 3885 received peripherally inserted central venous catheters (PICCs) and 34 396 received peripheral short catheters. In 3885 cases of PICCs, no CM extravasation occurred, but in five cases, ordinary PICCs that are unable to withstand high pressure were mistakenly used; three of those patients experienced catheter rupture, and eventually, all five patients underwent unplanned extubation. Among 34 396 cases of peripheral short catheters, 224 (0.65%) had CM extravasation. Female sex (odds ratio [OR]=1.541, 95% confidence interval [CI]: 1.111-2.137), diabetes (OR=2.265, 95% CI: 1.549-3.314), venous thrombosis (OR=2.157, 95% CI: 1.039-4.478), multi-site angiography (OR=9.757, CI: 6.803-13.994), and injection rate ≥ 3 mL/s (OR=6.073, 95% CI: 4.349-8.481) were independent risk factors for CM extravasation. Due to peripheral vascular protection measures in patients with malignant tumor, there was a low incidence of CM extravasation (OR=0.394, 95% CI: 0.272-0.570). CONCLUSION: Main risk factors for CM extravasation are female, diabetes, venous thrombosis, multi-site angiography, and injection rate ≥ 3 mL/s. However, patients with malignant tumor have a low incidence of CM extravasation. CLINICAL IMPACT: Analysis of these risk factors can help reduce the incidence of CM extravasation.


Assuntos
Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos , Humanos , Extravasamento de Materiais Terapêuticos e Diagnósticos/prevenção & controle , Extravasamento de Materiais Terapêuticos e Diagnósticos/epidemiologia , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Feminino , Masculino , Meios de Contraste/administração & dosagem , Meios de Contraste/efeitos adversos , Fatores de Risco , Pessoa de Meia-Idade , Idoso , Adulto , Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso de 80 Anos ou mais , Estudos de Coortes , Incidência
5.
Sci Rep ; 14(1): 3023, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321080

RESUMO

The optimization of railway construction schemes is a complexity system engineering task with multiple dimensions, diverse conditional constraints, and multifaceted objective assessments. The decision-making and scheme evaluation entail subjectivity, randomness, and fuzziness. To address the comprehensive optimization challenge in construction schemes effectively and efficiently, we investigate an optimization method for railway construction schemes. This method is based on multi-dimensional combination weighting and improved grey theory. After analyzing the primary influencing factors, we established a railway construction plan optimization index system comprising 4 dimensions and 18 factors. The weight combination coefficient is determined using the pros and cons solution distance method, and the optimal weight set for the index is determined through the multi-dimensional combination weighting approach. Utilizing the method of superior and inferior solution distance coupled with grey theory, we ascertain the order of advantages and disadvantages for each construction scheme, subsequently achieving construction scheme optimization. To illustrate this, we employ the optimization process for a high-speed railway section in Guangxi as an exemplar. The verification results indicate that the gray relative closeness values for schemes A, B, and C are 0.7089, 0.4813, and 0.4463, respectively. Scheme A has the highest gray relative closeness value, thus making it the optimal route scheme. The optimal results obtained through this method align with the outcomes of expert validation and existing research, thereby validating the effectiveness and practicality of the model. By employing a multidimensional combination weighting method, the deficiencies of traditional indicator weight calculations are mitigated, resulting in indicator weights that are more reflective of the actual circumstances. At the same time, the application of improvements in the grey theory comprehensive evaluation method enables the integration and computation of indicator data for each construction plan. Through the intuitive representation of grey relative closeness, the advantages and disadvantages of each plan are effectively characterized. This enhances the scientific rigor and applicability of the railway construction plan optimization process. The research findings can serve as a reference for similar railway construction scheme selection problems in the future.

6.
J Agric Food Chem ; 72(7): 3800-3813, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38327020

RESUMO

Folate was enriched during quinoa germination, while molecular mechanisms were not well understood. In this study, three quinoa varieties were selected for germination, and changes in substrate content and enzyme activity of the folate biosynthesis pathway were monitored. 5-Methyltetrahydrofolate (5-CH3-THF) and 5-formyltetrahydrofolate (5-CHO-THF) were significantly enriched in quinoa sprouts. Among the selected varieties, QL-2 exhibited the lowest content of the oxidation product MeFox and the highest total folate content. Based on transcriptome analysis, the p-ABA branch was found to be crucial for folate accumulation, while the pterin branch served as a key control point for the one carbon pool by folate pathway, which limited further folate biosynthesis. In the one carbon pool by folate pathway, genes CqMTHFR and CqAMT significantly contributed to the enrichment of 5-CH3-THF and 5-CHO-THF. Findings gained here would facilitate the potential application of quinoa sprouts as an alternative strategy for folate supplementation.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/genética , Chenopodium quinoa/química , Ácido Fólico , Sementes/genética , Sementes/química , Perfilação da Expressão Gênica , Carbono/análise
7.
Eur J Med Res ; 28(1): 458, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880738

RESUMO

OBJECTIVE: To identify the risk factors for moderate and severe contrast media extravasation and provide effective guidance to reduce the degree of extravasation injuries. METHODS: We observed 224 adult patients who underwent contrast media extravasation at Xiangya Hospital of Central South University, Hunan Provincial Maternal and Child Healthcare Hospital, and Xiangya Changde Hospital, Hunan Province between January 1, 2018 and December 31, 2022. Risk factors for moderate extravasation injuries were evaluated using univariate and multivariate logistic regression. RESULTS: Among 224 patients, 0 (0%) had severe, 18 (8.0%) had moderate, and 206 (92.0%) had mild contrast media extravasation injury. Multivariate logistic regression analysis revealed malignant tumors (odds ratio [OR] = 6.992, 95% confidence interval [CI]: 1.674-29.208), Iohexol (OR = 9.343, 95% CI 1.280-68.214), large-volume (> 50 mL) extravasation (OR = 5.773, 95% CI 1.350‒24.695), and injection site (back of the hand) (OR = 13.491, 95% CI 3.056-59.560) as independent risk factors for moderate injury. CONCLUSION: Risk factors for moderate contrast media extravasation injury are malignant tumors, iohexol, large-volume (> 50 mL) extravasation, and back-of-the-hand injection. Analysis of these risk factors can help reduce the degree of injury after extravasation. CLINICAL RELEVANCE STATEMENT: High-risk patients with extravasation support should choose the appropriate contrast media type, avoiding back-of-the-hand injections. We recommend that patients with cancer be implanted with a high-pressure resistant central venous catheter and receive effective measures to timely detect and reduce extravasation.


Assuntos
Extravasamento de Materiais Terapêuticos e Diagnósticos , Neoplasias , Adulto , Humanos , Meios de Contraste/efeitos adversos , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Iohexol/efeitos adversos , Estudos Prospectivos , Tomografia Computadorizada por Raios X
8.
Micromachines (Basel) ; 14(10)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37893394

RESUMO

The MEMS gyroscope is one of the basic units of inertial navigation, whose performance and accuracy is noteworthy. Because of the limitations of processing technology and other factors, the relative manufacturing error of MEMS gyroscopes is usually large. Errors directly lead to a frequency mismatch of resonant structures and consequently restrict the performance improvement of the gyroscope. This study proposes a mechanical trimming technique combining the addition and removal of gold in a ring MEMS gyroscope. Firstly, the analysis of the gyroscope dynamics and error model and trimming theory provides theoretical guidance for the trimming process. Secondly, the method of adjusting the mass is investigated, and the ablation threshold of femtosecond laser parameters on gold is analyzed, which provides the process with parameters for the trimming experiment. Finally, the frequency trimming process is conducted in three steps, including the addition of gold spheres and the removal of gold spheres and gold film, which are applicable to the trimming process at different rates of frequency split. The results shows that the proposed method can reduce the frequency split of the gyroscope from 4.36 to 0.017 Hz.

9.
Gene ; 888: 147752, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37661029

RESUMO

Isatis indigotica Fortune is a plant species containing lignan compounds of significant economic value. Its root plays a crucial role in treating viruses and exhibits antitumor, anti-inflammatory, antibacterial, and other biological activities. Now, I. indigotica has been included in Isatis tinctoria Linnaeus. In this study, the roots of diploid I. indigotica, tetraploid I. indigotica, and Isatis tinctoria Linnaeus were analyzed using metabolome and transcriptome analysis. The metabolomic analysis detected 48 lignan metabolites, including Lirioresinol A, Vladinol A, Syringaresinol, Arctigenin, Acanthoside B, and Sesamin as characteristic compounds, without significant variations among the remaining metabolites. The transcriptomic analysis identified 41 differentially expressed phenylpropanoid synthase genes, which were further analyzed for variations in lignan transcriptome profiles across different samples. RT-qPCR analysis also revealed differential genes expression related to lignan biosynthesis pathway among the three sample groups. The analysis of transcription factors showed that the AP2-EREBP family (Iin24319), MYB family (Iin24843), and WRKY family (Iin08158) displayed expression patterns similar to Iin14549. Phylogenetic analyses also indicate that Iin14549 may play a role in lignan synthesis. These transcription factor families exhibited high expression in tetraploid I. indigotica, moderate expression in diploid I. indigotica, and low expression in I. tinctoria. The findings of this study can serve as a reference for improving the quality of I. indigotica and developing germplasms with high lignan content. Additionally, these results lay a foundation for the functional characterization of UGTs in lignan biosynthesis pathway.

10.
Intensive Crit Care Nurs ; 79: 103491, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37480701

RESUMO

OBJECTIVES: This study aimed to investigate the prevalence and risk factors for carbapenem-resistant Enterobacterales colonisation/infection at admission and acquisition among patients admitted to the intensive care unit. RESEARCH METHODOLOGY/DESIGN: A prospective and multicentre study. SETTING: This study was conducted in 24 intensive care units in Anhui, China. MAIN OUTCOME MEASURES: Demographic and clinical data were collected, and rectal carbapenem-resistant Enterobacterales colonisation was detected by active screening. Multivariate logistic regression models were used to analyse factors associated with colonisation/infection with carbapenem-resistant Enterobacterales at admission and acquisition during the intensive care unit stay. RESULTS: There were 1133 intensive care unit patients included in this study. In total, 5.9% of patients with carbapenem-resistant Enterobacterales colonisation/infection at admission, and of which 56.7% were colonisations. Besides, 8.5% of patients acquired carbapenem-resistant Enterobacterales colonisation/infection during the intensive care stay, and of which 67.6% were colonisations. At admission, transfer from another hospital, admission to an intensive care unit within one year, colonisation/infection/epidemiological link with carbapenem-resistant Enterobacterales within one year, and exposure to any antibiotics within three months were risk factors for colonisation/infection with carbapenem-resistant Enterobacterales. During the intensive care stay, renal disease, an epidemiological link with carbapenem-resistant Enterobacterales, exposure to carbapenems and beta-lactams/beta-lactamase inhibitors, and intensive care stay of three weeks or longer were associated with acquisition. CONCLUSION: The prevalence of colonisation/infection with carbapenem-resistant Enterobacterales in intensive care units is of great concern and should be monitored systematically. Particularly for the 8.5% prevalence of carbapenem-resistant Enterobacterales acquisition during the intensive care stay needs enhanced infection prevention and control measures in these setting. Surveillance of colonisation/infection with carbapenem-resistant Enterobacterales at admission and during the patient's stay represents an early identification tool to prevent further transmission of carbapenem-resistant Enterobacterales. IMPLICATIONS FOR CLINICAL PRACTICE: Carbapenem-resistant Enterobacterales colonization screening at admission and during the patient's stay is an important tool to control carbapenem-resistant Enterobacterales spread in intensive care units.


Assuntos
Carbapenêmicos , Unidades de Terapia Intensiva , Humanos , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Prevalência , Estudos Prospectivos , Fatores de Risco
11.
Int J Genomics ; 2023: 8437898, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056786

RESUMO

Vascular smooth muscle cells (VSMCs) are critical elements of the vascular wall and play a crucial role in the genesis and development of atherosclerosis (AS). Increasingly, studies have indicated that long noncoding RNAs (lncRNAs) regulate VSMC proliferation, apoptosis, and other biological processes. Nevertheless, the role of lncRNA NFIA-AS1 (hereinafter referred to as NFIA-AS1) in VSMCs and AS remains unclear. Quantitative real-time PCR (qRT-PCR) was performed to analyze the messenger RNA (mRNA) levels of NFIA-AS1 and miR-125a-3p. CCK-8 and EdU staining were performed to detect VSMC proliferation. VSMC apoptosis was evaluated by flow cytometry. The expression of various proteins was detected using western blotting. The levels of inflammatory cytokines secreted by VSMCs were measured by enzyme linked immunosorbent assay (ELISA). The binding sites of NFIA-AS1 and miR-125a-3p, as well as miR-125a-3p and AKT1, were analyzed using bioinformatics methods and validated using a luciferase reporter assay. The function of NFIA-AS1/miR-125a-3p/AKT1 in VSMCs was clarified through loss- and gain-of-functional experiments. We confirmed that NFIA-AS1 was highly expressed in AS tissues and VSMCs induced by oxidized low-density lipoprotein (Ox-LDL). Knockdown of NFIA-AS1 restrained the exceptional growth of Ox-LDL-induced VSMCs, promoted their apoptosis, and decreased the secretion of inflammatory factors and expression of adhesion factors. In addition, NFIA-AS1 regulated the proliferation, apoptosis, and inflammatory response of VSMCs through the miR-125a-3p/AKT1 axis, suggesting that NFIA-AS1 may be a potential therapeutic target for AS.

12.
J Ethnopharmacol ; 313: 116481, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37072090

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The combined prescription of two classical decoctions (Ma-Xing-Shi-Gan decoction with Xiao-Chai-Hu decoction), named as San-Yang-He-Zhi (SYHZ) decoction, has been widely used for the treatment of influenza virus (IFV) infections for decades. AIM OF THE STUDY: This study aimed to evaluate the anti-influenza effect of SYHZ decoction and explore the underlying mechanism. MATERIALS AND METHODS: The ingredients of SYHZ decoction were analyzed by mass spectrometry. An animal model of IFV infection was established by challenging C57BL/6J mice with PR8 virus. Three groups of mice were infected with lethal or non-lethal doses of IFV, then followed by oral administration of phosphate-buffered saline (PBS), or SYHZ, or oseltamir; blank control mice (without IFV infection) were treated with PBS. Survival rate, Lung index, colon length, body weight loss and IFV viral load were measured 7 days post infection; histology and electron-microscopy examinations of lung tissue were performed; cytokine and chemokine levels in lung and serum were measured; and the intestinal metagenome, the cecum metabolome, and the lung transcriptome were analyzed. RESULTS: SYHZ treatment significantly improved survival rate compared with PBS (40% vs 0%); improved lung index, colon length, and body weight loss; and alleviated lung histological damage and viral load. SYHZ-treated mice had significantly lower levels of IL-1ß, TNF-α, IL-6, CCL2, CXCL10 in lung and serum, and increased levels of multiple bioactive components in cecum. Pro-inflammatory cytokines, Toll- and NOD-like receptors, pro-apoptosis molecules, and lung-injury-related proteins were downregulated in SYHZ mice, whereas surfactant protein and mucin were upregulated. The NOD-like receptor pathway, Toll-like receptor pathway, and NF-κB pathway were downregulated by SYHZ treatment. CONCLUSIONS: SYHZ decoction alleviated IFV infection in a mouse model. Multiple bioactive ingredients of SYHZ may inhibit replication of IFV and suppress excessive immune response.


Assuntos
Medicamentos de Ervas Chinesas , Infecções por Orthomyxoviridae , Orthomyxoviridae , Camundongos , Animais , Camundongos Endogâmicos C57BL , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Pulmão , Citocinas/metabolismo , Orthomyxoviridae/metabolismo , Replicação Viral , Redução de Peso
13.
Biomed Pharmacother ; 162: 114660, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37058819

RESUMO

Multidrug-resistance (MDR) Pseudomonas aeruginosa (P. aeruginosa) is a lethal gram-negative pathogen causing hospital-acquired and ventilator-associated pneumonia, which is difficult to treat. Our previous studies confirmed that baicalin, an essential bioactive component in Scutellaria baicalensis Georgi, exhibited anti-inflammatory effects in an acute pneumonia rat model induced by MDR P. aeruginosa. However, this effect of baicalin in constrast its low bioavailability, and its mechanism of action is still unknown. Thus, this study investigated whether the therapeutic effects of baicalin against MDR P. aeruginosa acute pneumonia are owing to the regulation of gut microbiota and their metabolites using pyrosequencing of the 16S rRNA genes in rat feces and metabolomics. As a result, baicalin attenuated the inflammation by acting directly on neutrophils and regulated the production of the inflammatory cytokines TNF-α, IL-1ß, IL-6, and IL-10. The mechanisms were through down-regulation of TLR4 and inhibition of NF-κB. Furthermore, pyrosequencing of the 16S rRNA genes in rat feces revealed that baicalin regulated the composition of gut microbial communities. At the genus level, baicalin efficiently increased the abundance of Ligilactobacillus, Lactobacillus and Bacteroides, but decreased the abundance of Muribaculaceae and Alistipes. Further, arginine biosynthesis was analyzed as the core pathway regulated by baicalin via combination with predicting gut microbiota function and targeted metabolomics. In conclusion, this study has demonstrated that baicalin relieved inflammatory injury in acute pneumonia rat induced by MDR P. aeruginosa via arginine biosynthesis associated with gut microbiota. Baicalin could be a promising and effective adjunctive therapy for lung inflammation caused by MDR P. aeruginosa infection.


Assuntos
Pneumonia , Pseudomonas aeruginosa , Ratos , Animais , RNA Ribossômico 16S , Inflamação/tratamento farmacológico , Pneumonia/tratamento farmacológico , Flavonoides/farmacologia , Arginina/farmacologia
14.
J Xray Sci Technol ; 31(3): 463-482, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776028

RESUMO

BACKGROUND: The Mueller, Siddon and Joseph weighting algorithms are frequently used for projection and back-projection, which are relatively complicated when they are implemented in computer code. OBJECTIVE: This study aims to reduce the actual complexity of the projection and back-projection. METHODS: First, we neglect the exact shape of the pixel, so that its shadow is a rectangle projecting precisely to a detector bin, which implies that all the pixel weights are exactly 1 for each ray through them, otherwise are exactly 0. Next, a one-to-one reversible image rotation algorithm (RIRA) is proposed to compute the projection and back-projection, where two one-to-one mapping lists namely, U and V, are used to store the coordinates of a rotated pixel and its corresponding new coordinates, respectively. For each 2D projection, the projection is simply the column sum in each orientation according to the lists U and V. For each 2D back-projection, it is simply to arrange the projection to the corresponding column element according to the lists U and V. Thus, there is no need for an interpolation in the projection and back-projection. Last, a rotating image computed tomography (RICT) based on RIRA is proposed to reconstruct the image. RESULTS: Experiments show the RICT reconstructs a good image that is close to the result of filtered back-projection (FBP) method according to the RMSE, PSNR and MSSIM values. What's more, our weight, projection and back-projection are much easier to be implemented in computer code than the FBP method. CONCLUSION: This study demonstrates that the RIRA method has potential to be used to simplify many computed tomography image reconstruction algorithms.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Rotação , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos
15.
Small ; 19(15): e2206742, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36617521

RESUMO

High-entropy alloys (HEAs) are attracting increased attention as an alternative to noble metals for various catalytic reactions. However, it is of great challenge and fundamental importance to develop spatial HEA heterostructures to manipulate d-band center of interfacial metal atoms and modulate electron-distribution to enhance electrocatalytic activity of HEA catalysts. Herein, an efficient strategy is demonstrated to construct unique well-designed HEAs spatial heterostructure electrocatalyst (HEA@Pt) as bifunctional cathode to accelerate oxygen reduction and evolution reaction (ORR/OER) kinetics for Li-O2 batteries, where uniform Pt dendrites grow on PtRuFeCoNi HEA at a low angle boundary. Such atomically connected HEA spatial interfaces engender efficient electrons from HEA to Pt due to discrepancy of work functions, modulating electron distribution for fast interfacial electron transfer, and abundant active sites. Theoretical calculations reveal that electron redistribution manipulates d-band center of interfacial metal atoms, allowing appropriate adsorption energy of oxygen species to lower ORR/OER reaction barriers. Hence, Li-O2 battery based on HEA@Pt electrocatalyst delivers a minimal polarization potential (0.37 V) and long-term cyclability (210 cycles) under a cut-off capacity of 1000 mAh g-1 , surpassing most previously reported noble metal-based catalysts. This work provides significant insights on electron-modulation and d-band center optimization for advanced electrocatalysts.

16.
Front Oncol ; 12: 959502, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408132

RESUMO

Lung adenocarcinoma, the most common subtype of lung cancer, has been always imposed serious threat to human health. Congenital pulmonary dysplasia (CPD) lacking typical clinical manifestations is a rare developmental anomaly. Pulmonary aplasia, the rarest subtype of CPD, may present with a variety of symptoms and is frequently associated with other abnormalities. This report describes an 81-year-old woman who presented with an irritant cough. Chest computed tomography (CT) and three-dimensional (3D) reconstruction revealed an irregular mass with a diameter of 5 cm in right lower lobe adjacent to the hilum. CT also indicated a rightward mediastinal shift and the complete absence of ipsilateral upper lobar tissue with bronchus ending in a terminal cecum, resulting in a diagnosis of pulmonary aplasia. The patient accepted lobectomy and lymph node dissection without complication, histopathologic examination combined HE staining with immunohistochemistry identified the tumor as adenocarcinoma. Three months after surgery, the patient was free of respiratory symptoms without chest pain. This report highlights the necessity of comprehensive evaluation for lung malignancy concurrent with CPD and the importance of identifying the diagnosis of pulmonary dysplasia.

17.
Adv Mater ; 34(41): e2205575, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36028217

RESUMO

Developing quasi-solid-state electrolytes with superior ionic conductivity and high mechanical strength is urgently desired to improve the safety and cycling stability of lithium-metal batteries. Herein, a novel solid-like electrolyte (SLE) with enhanced Li+ interfacial transfer kinetics is rationally designed by soaking bulk nanostructured silica-polymer composites in liquid electrolytes. Benefiting from the high content of inorganic silica and abundant interfaces for fast Li+ -transport channels, the prepared SLE exhibits superb ionic conductivity and high mechanical strength. Furthermore, fumed silica with a high specific area in the SLE can homogenize Li+ flux and electrical field gradient. More importantly, a Li2 S-rich solid electrolyte interphase (SEI) is constructed on the lithium metal due to the intimate ion coordination in the SLE. Therefore, the lithium-metal anode exhibits excellent electrochemical performance in symmetric Li-Li cells due to the merits of superior ionic conductivity, high modulus, Li2 S-rich SEI, as well as the homogeneous Li+ flux. Full cells with LiFePO4 cathode can still display a capacity retention of 98% at 0.2 C after 400 cycles. The proposed strategy on quasi-solid-state electrolytes provides a promising avenue for next-generation metal-based batteries.

18.
Micromachines (Basel) ; 13(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35888867

RESUMO

MEMS gyroscopes play an important role in inertial navigation measurements, which mainly works in n = 2 mode. However, mode matching is the basis for high-precision detection, which can improve the sensitivity, resolution, and signal-to-noise ratio of the gyroscopes. An initial frequency split is inevitably generated during the manufacturing process. There are two methods to eliminate the frequency split and to achieve mode matching for the gyroscopes, which are electrostatic tuning and mechanical trimming, respectively. In this paper, we report a novel ring MEMS resonator and a novel method of mechanical frequency tuning. The most prominent characteristic of the resonator is that 16 raised mass blocks are increased in the circumferential positions of the ring uniformly. This structural design can achieve mass-stiffness decoupling, which means that punching holes on the mass blocks only affects the mass distribution but the stiffness is almost unchanged for the resonator. We verify the mass-stiffness decoupling by way of comparing the simulation with the conventional resonator. In addition, we put up an online tuning platform based on a femtosecond laser and reduce a resonator's frequency split from 23.3 Hz to 0.4 Hz, which reveals that the frequency split is linearly related to the removed mass. These findings will have a referential significance for other transducers.

19.
Dis Markers ; 2022: 1832241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35872696

RESUMO

Esophageal cancer (EC) is a common malignant tumor of the digestive system. Exploring the molecular biological mechanism of EC will help to clarify its carcinogenesis mechanism, find important molecular targets in the process of carcinogenesis, and provide new ideas for the diagnosis and treatment of EC. Phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway is one of the signal transduction pathways most closely related to cell proliferation and apoptosis. The regulation of various downstream molecules affects the proliferation and growth of tumor cells. In this study, we determined the effect of different concentrations of afuresertib on cell viability by MTT assay and determined the effect of afuresertib on cell apoptosis by Annexin V-FITC/PI dual staining. Animal experiments verified the effects of afuresertib on VEGF, bFGF, and PI3K/Akt. Our results indicated that afuresertib is closely related to the survival, proliferation, and apoptosis of esophageal cancer cell lines. More importantly, we found that afuresertib could reduce tumor volume and mass in EC rats through in vivo experiments. In conclusion, afuresertib may exert its antitumor effect by inhibiting the expression of PI3K and Akt-related proteins in rat tumor tissues.


Assuntos
Neoplasias Esofágicas , Proteínas Proto-Oncogênicas c-akt , Animais , Apoptose , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis , Ratos , Tiofenos
20.
Front Pharmacol ; 13: 874068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677448

RESUMO

Influenza virus-caused lung infection and its pandemic outbreaks are a persistent public health challenge. The H1N1 subtype is the most common type of influenza infection observed in humans. Maxingshigantang decoction, a classic formula of Chinese herbal medicine, has been used for the prevention and treatment of respiratory infection for many centuries. Qingfeiyin decoction, based on Maxingshigantang, has been used in the clinic for decades. To explore the underlying mechanisms, according to the traditional Chinese medicine theory "the lung and the large intestine are interior-exterior," which can be translated to the "gut-lung axis" in a contemporary term, the composition of gut microbiota was determined using 16S rRNA and the transcriptome of the colon was determined by RNA sequencing. The results showed that Qingfeiyin decoction decreased the viral load, alleviated the lung injury, increased the survival rate, partly restored the shortening of the colon caused by the H1N1 virus, and downregulated inflammatory pathways including MAPK, TNFα, and JAK-STAT signaling pathways. Qingfeiyin decoction increased the relative abundance of the genera of Coprococcus , Ruminococcus, Lactobacillus, and Prevotella and prevented the H1N1 virus-induced decrease in the abundance of the genera of Escherichia, Parabacteroides, Butyricimonas, and Anacrotruncus. These results will help better understand the mechanisms for Qingfeiyin decoction's protective effect against influenza virus infection.

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