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1.
Inorg Chem ; 63(16): 7442-7454, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38606439

RESUMO

As electrocatalysts, molecular catalysts with large aromatic systems (such as terpyridine, porphyrin, or phthalocyanine) have been widely applied in the CO2 reduction reaction (CO2RR). However, these monomeric catalysts tend to aggregate due to strong π-π interactions, resulting in limited accessibility of the active site. In light of these challenges, we present a novel strategy of active site isolation for enhancing the CO2RR. Six Ru(Tpy)2 were integrated into the skeleton of a metallo-organic supramolecule by stepwise self-assembly in order to form a rhombus-fused six-pointed star R1 with active site isolation. The turnover frequency (TOF) of R1 was as high as 10.73 s-1 at -0.6 V versus reversible hydrogen electrode (vs RHE), which is the best reported value so far at the same potential to our knowledge. Furthermore, by increasing the connector density on R1's skeleton, a more stable triangle-fused six-pointed star T1 was successfully synthesized. T1 exhibits exceptional stability up to 126 h at -0.4 V vs RHE and excellent TOF values of CO. The strategy of active site isolation and connector density increment significantly enhanced the catalytic activity by increasing the exposure of the active site. This work provides a starting point for the design of molecular catalysts and facilitates the development of a new generation of catalysts with a high catalytic performance.

2.
BMC Psychiatry ; 24(1): 243, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566037

RESUMO

BACKGROUND: Bipolar disorder (BD) is a severe mental disorder with heavy disease burden. Females with BD are special populations who suffer a lot from childhood trauma, social support, cognitive deficits, and suicidality. In this study, the relationship among childhood trauma, social support, and clinical symptoms of BD was investigated and the risk factors for suicidality were explored in female patients with BD. METHODS: This study included 57 drug-naive female BD patients, 64 female BD patients with long-term medication, and 50 age-matched female healthy controls. Childhood trauma, social support, clinical symptoms, cognition, and suicidality (suicide ideation, suicide plan, suicide attempt, suicide frequency) were measured with scales. RESULTS: Compared with healthy controls, females with BD showed higher levels of childhood trauma and suicidality, and lower levels of social support and cognitive deficits. In the drug-naïve BD group, social support mediated the relationship between childhood trauma and insomnia symptoms (indirect effect: ab = 0.025). In the BD with long-term medication group, mania symptom was associated with suicide plan (OR = 1.127, p = 0.030), childhood trauma was associated with suicide attempt (OR = 1.088, p = 0.018), and years of education (OR = 0.773, p = 0.028), childhood trauma (OR = 1.059, p = 0.009), and delayed memory (OR= 1.091, p= 0.016) was associated with suicide frequency (OR = 1.091, p = 0.016). CONCLUSIONS: This study provides initial evidence that social support partially explains the relationship between childhood trauma and clinical symptoms in females with BD. Additionally, mania symptoms, childhood trauma, and delayed memory were risk factors for suicidality. Interventions providing social support and improving cognitive function may be beneficial for females with BD who are exposed to childhood trauma and with high suicide risk.


Assuntos
Experiências Adversas da Infância , Transtorno Bipolar , Suicídio , Humanos , Feminino , Transtorno Bipolar/complicações , Transtorno Bipolar/psicologia , Mania/complicações , Ideação Suicida , Cognição , Apoio Social
3.
Small ; 20(15): e2311510, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38267811

RESUMO

Zinc-bromine (Zn-Br) redox provides a high energy density and low-cost option for next-generation energy storage systems, and polybromide diffusion remains a major issue leading to Zn anode corrosion, dendrite growth, battery self-discharge and limited electrochemical performance. A dual-functional Alginate-Graphene Oxide (AGO) hydrogel coating is proposed to prevent polybromide corrosion and suppress dendrite growth in Zn-Br batteries through negatively charged carboxyl groups and enhanced mechanical properties. The battery with anode of plain zinc coated with AGO (Zn]AGO) survives a severely corrosive environment with higher polybromide concentration than usual without a membrane, and achieves 80 cycles with 100% Coulombic and 80.65% energy efficiencies, four times compared to plain Zn anode. The promising performance is comparable to typical Zn-Br batteries using physical membranes, and the AGO coating concept can be well adapted to various Zn-Br systems to promote their applications.

4.
Adv Sci (Weinh) ; 11(7): e2307780, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38168899

RESUMO

Batteries dissolving active materials in liquids possess safety and size advantages compared to solid-based batteries, yet the intrinsic liquid properties lead to material cross-over induced self-discharge both during cycling and idle when the electrolytes are in contact, thus highly efficient and cost-effective solutions to minimize cross-over are in high demand. An ultra-low self-discharge aqueous|organic membraneless battery using dichloromethane (CH2 Cl2 ) and tetrabutylammonium bromide (TBABr) added to a zinc bromide (ZnBr2 ) solution as the electrolyte is demonstrated. The polybromide is confined in the organic phase, and bromine (Br2 ) diffusion-induced self-discharge is minimized. At 90% state of charge (SOC), the membraneless ZnBr2 |TBABr (Z|T) battery shows an open circuit voltage (OCV) drop of only 42 mV after 120 days, 152 times longer than the ZnBr2  battery, and superior to 102 previous reports from all types of liquid active material batteries. The 120-day capacity retention of 95.5% is higher than commercial zinc-nickel (Zn-Ni) batteries and vanadium redox flow batteries (VRFB, electrolytes stored separately) and close to lithium-ion (Li-ion) batteries. Z|T achieves >500 cycles (2670 h, 0.5 m electrolyte, 250 folds of membraneless ZnBr2  battery) with ≈100% Coulombic efficiency (CE). The simple and cost-effective design of Z|T provides a conceptual inspiration to regulate material cross-over in liquid-based batteries to realize extended operation.

5.
Ultrasound Q ; 39(4): 228-234, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918027

RESUMO

ABSTRACT: The application of intracavity contrast-enhanced ultrasound in the evaluation of biliary disease has been confirmed valuable among pediatric population. This pictorial essay aims to demonstrate the role of percutaneous ultrasound cholangiography (PUSC) with microbubbles in the diagnosis of different pediatric biliary diseases in our center. The biliary system's morphologic characteristics in PUSC mode of neonatal hepatitis, biliary atresia, choledochal cysts, and biliary complications of hepatobiliary surgery are presented.


Assuntos
Atresia Biliar , Sistema Biliar , Recém-Nascido , Criança , Humanos , Lactente , Microbolhas , Colangiografia , Sistema Biliar/diagnóstico por imagem , Atresia Biliar/diagnóstico por imagem , Atresia Biliar/complicações , Ultrassonografia
6.
Hepatol Res ; 53(11): 1126-1133, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37519259

RESUMO

AIMS: Infants with biliary atresia (BA) are treated with Kasai portoenterostomy (KPE) surgery, but many BA patients need subsequent salvage liver transplants. The aim of this study is to develop a comprehensive gene-clinical model based on two-dimensional shear wave elastography (2DSWE), liver gene expression, and other clinical parameters to predict response to KPE for BA patients. METHODS: Differentially expressed gene patterns between liver samples of BA (n = 102) and non-BA control (n = 14) were identified using RNA sequencing analysis. Biliary atresia patients were then randomly assigned to training and validation cohorts. Gene classifier based on the differentially expressed genes was built in the training cohort. Nomogram models with and without gene classifier were further constructed and validated for predicting native liver survival of BA patients. The utility of the nomograms was compared by C-index. RESULTS: Using the least absolute shrinkage and selection operator model, we generated a nine-gene prognostic classifier. The nomogram based on the nine-gene classifier, age, preoperative 2DSWE, and albumin had the better C-index compared to gene classifier alone in the training cohort (0.83 [0.76-0.90] vs. 0.69 [0.61-0.77], p = 0.003) and the validation cohort (0.74 [0.67-0.82] vs. 0.62 [0.55-0.70], p = 0.001). Using risk scores developed from the nomogram, the 12-month survival rates of BA patients with native liver were 35.7% (95% confidence interval [CI], 22.7-56.3) in the high-risk group and 80.8% (95% CI, 63.4-100.0) in the low-risk group in the validation cohort. CONCLUSIONS: The comprehensive genetic-clinical nomogram based on preoperative 2DSWE, liver gene expression, and other clinical parameters can accurately predict response to KPE.

7.
Eur Radiol ; 33(12): 9328-9335, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37389607

RESUMO

OBJECTIVES: To modify the size cutoff for biopsy for thyroid nodules in patients < 19 years based on the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) and evaluate the performance of the new criteria in two referral centers. METHODS: Patients < 19 years with cytopathologic or surgical pathology results were retrospectively identified from two centers from May 2005 to August 2022. Patients from one center were classified as the training cohort, and those from the other center were classified as the validation cohort. The diagnostic performance, unnecessary biopsy rates, and missed malignancy rates of the TI-RADS guideline, and the new criteria (≥ 35 mm for TR3 and no threshold for TR5) were compared. RESULTS: A total of 236 nodules from 204 patients in the training cohort and 225 nodules from 190 patients in the validation cohort were analyzed. The area under the receiver operating characteristic curve of the new criteria in identifying thyroid malignant nodules was higher (0.809 vs. 0.681, p < 0.001; 0.819 vs. 0.683, p < 0.001), and the unnecessary biopsy rates (45.0% vs. 56.8%; 42.2% vs. 56.8%) and missed malignancy rates (5.7% vs. 18.6%; 9.2% vs. 21.5%) were lower than that of the TI-RADS guideline in the training cohort and validation cohort, respectively. CONCLUSIONS: The new criteria (≥ 35 mm for TR3 and no threshold for TR5) for biopsy based on the TI-RADS may help improve the diagnostic performance and reduce unnecessary biopsy rates and missed malignancy rates for thyroid nodules in patients < 19 years. CLINICAL RELEVANCE STATEMENT: The study developed and validated the new criteria (≥ 35 mm for TR3 and no threshold for TR5) to indicate FNA based on the ACR TI-RADS of thyroid nodules in patients younger than 19 years. KEY POINTS: •The AUC of the new criteria (≥ 35 mm for TR3 and no threshold for TR5) in identifying thyroid malignant nodules was higher than that of the TI-RADS guideline (0.809 vs. 0.681) in patients < 19 years. •The unnecessary biopsy rates and missed malignancy rates of the new criteria (≥ 35 mm for TR3 and no threshold for TR5) in identifying thyroid malignant nodules were lower than that of the TI-RADS guideline in patients < 19 years (45.0% vs. 56.8% and 5.7% vs. 18.6%, respectively).


Assuntos
Radiologia , Nódulo da Glândula Tireoide , Humanos , Estados Unidos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Estudos Retrospectivos , Ultrassonografia/métodos , Biópsia
8.
Fish Shellfish Immunol ; 138: 108839, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37207883

RESUMO

Cromileptes altivelis (humpback grouper) is the main farmed species in the southern coastal area of China owing to its important economic value. Toll-like receptor 9 (TLR9) belongs to the toll-like receptor (TLR) family and functions as a pattern recognition receptor, recognising unmethylated oligodeoxynucleotides containing the CpG motif (CpG ODNs) in bacterial and viral genomes, thereby activating host immune response. In this study, the C. altivelis TLR9 (CaTLR9) ligand CpG ODN 1668 was screened and found to significantly enhance the antibacterial immunity of humpback grouper in vivo and head kidney lymphocytes (HKLs) in vitro. In addition, CpG ODN 1668 also promoted the cell proliferation and immune gene expression of HKLs and strengthened the phagocytosis activity of head kidney macrophages. However, when the CaTLR9 expression was knocked down in the humpback group, the expression levels of TLR9, myeloid differentiation factor 88 (Myd88), tumour necrosis factor-α (TNF-α), interferon γ (IFN-γ), interleukin-1ß (IL-1ß), IL-6, and IL-8 were significantly reduced, and the antibacterial immune effects induced by CpG ODN 1668 were mostly abolished. Therefore, CpG ODN 1668 induced antibacterial immune responses in a CaTLR9-dependent pathway. These results enhance the knowledge of the antibacterial immunity of fish TLR signalling pathways and have important implications for exploring natural antibacterial molecules in fish.


Assuntos
Bass , Receptor Toll-Like 9 , Animais , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Bass/genética , Bass/metabolismo , Adjuvantes Imunológicos/farmacologia , Oligodesoxirribonucleotídeos/farmacologia , Imunidade
9.
Inorg Chem ; 62(17): 6537-6543, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37074131

RESUMO

In the past decades, many supramolecular cages with different sizes and shapes have been achieved through coordination-driven self-assembly. However, the strategy of topology adjustment by using a steric hindrance effect has not been fully developed. In this Article, we report the synthesis of ligand LA with rotatable arms, ligand LB with restricted arms, and their precisely controlled self-assembly to tetramer cage T1 and dimer cage D1, respectively, under the same conditions. By utilizing the steric hindrance of the ligands, the shapes and sizes of metallosupramolecular cages have been successfully adjusted. The metallocages were characterized by NMR spectroscopy (1H, 13C, COSY, NOESY, and DOSY), mass spectrometry (ESI-MS, TWIM-MS), transmission electron microscopy, and atomic force microscopy. This synthetic method would have the potential to be a general strategy for the design and self-assembly of diverse cages with tunable shape, size, and applicable properties.

10.
Intensive Care Med ; 49(4): 401-410, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36892598

RESUMO

PURPOSE: Central venous catheter (CVC)-related thrombosis (CRT) is a known complication in critically ill patients. However, its clinical significance remains unclear. The objective of the study was to evaluate the occurrence and evolution of CRT from CVC insertion to removal. METHODS: A prospective multicenter study was conducted in 28 intensive care units (ICUs). Duplex ultrasound was performed daily from CVC insertion until at least 3 days after CVC removal or before patient discharge from the ICU to detect CRT and to follow its progression. CRT diameter and length were measured and diameter > 7 mm was considered extensive. RESULTS: The study included 1262 patients. The incidence of CRT was 16.9% (95% confidence interval 14.8-18.9%). CRT was most commonly found in the internal jugular vein. The median time from CVC insertion to CRT onset was 4 (2-7) days, and 12% of CRTs occurred on the first day and 82% within 7 days of CVC insertion. CRT diameters > 5 mm and > 7 mm were found in 48% and 30% of thromboses. Over a 7-day follow-up, CRT diameter remained stable when the CVC was in place, whereas it gradually decreased after CVC removal. The ICU length of stay was longer in patients with CRT than in those without CRT, and the mortality was not different. CONCLUSION: CRT is a frequent complication. It can occur as soon as the CVC is placed and mostly during the first week following catheterization. Half of the thromboses are small but one-third are extensive. They are often non-progressive and may be resolved after CVC removal.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Trombose Venosa Profunda de Membros Superiores , Humanos , Cateteres Venosos Centrais/efeitos adversos , Cateterismo Venoso Central/efeitos adversos , Estado Terminal/terapia , Estudos Prospectivos , Sistemas Automatizados de Assistência Junto ao Leito , Trombose Venosa Profunda de Membros Superiores/epidemiologia , Trombose Venosa Profunda de Membros Superiores/etiologia
11.
Angew Chem Int Ed Engl ; 62(1): e202214237, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36323638

RESUMO

Fractal structures with self-similarity are of fundamental importance in the fields of aesthetic, chemistry and mathematics. Here, by taking advantage of constructs the rational geometry-directed precursor design, we report the construction of two fascinating Platonic solids, the Sierpinski tetrahedron ST-T and the Sierpinski octahedron ST-O, in which each possesses a fractal Sierpinski triangle on their independent faces. These two discrete complexes are formed in near-quantitative yield from the multi-component self-assembly of truncated Sierpinski triangular kernel L1 with tribenzotriquinacene-based hexatopic and anthracene-based tetratopic terpyridine ligands (L3 and L4 ) in the presence of metal ions, respectively. The enhanced stabilities of the 3D discrete structures were investigated by gradient tandem mass spectrometry (gMS2 ). This work provides new constructs for the imitation of complex virus assemblies and for the molecular encapsulation of giant guest molecules.


Assuntos
Espectrometria de Massas em Tandem , Ligantes
12.
Sensors (Basel) ; 22(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36298280

RESUMO

In view of the limited number of extracted sound features, the lack of in-depth analysis of applicable sound features, and the lack of in-depth study of the selection basis and optimization process of classification models in the existing broiler sound classification or recognition research, the author proposes a recognition method for broiler sound signals based on multi-domain sound features and classification models. The implementation process is divided into the training stage and the testing stage. In the training stage, the experimental area is built, and multiple segments of broiler sound signals are collected and filtered. Through sub-frame processing and endpoint detection, the combinations of start frames and end frames of multiple sound types in broiler sound signals are obtained. A total of sixty sound features from four aspects of time domain, frequency domain, Mel-Frequency Cepstral Coefficients (MFCC), and sparse representation are extracted from each frame signal to form multiple feature vectors. These feature vectors are labeled manually to build the data set. The min-max standardization method is used to process the data set, and the random forest is used to calculate the importance of sound features. Then, thirty sound features that contribute more to the classification effect of the classification model are retained. On this basis, the classification models based on seven classification algorithms are trained, the best-performing classification model based on k-Nearest Neighbor (kNN) is obtained, and its inherent parameters are optimized. Then, the optimal classification model is obtained. The test results show that the average classification accuracy achieved by the decision-tree-based classifier (abbreviated as DT classifier) on the data set before and after min-max standardization processing is improved by 0.6%, the average classification accuracy achieved by the DT classifier on the data set before and after feature selection is improved by 3.1%, the average classification accuracy achieved by the kNN-based classification model before and after parameter optimization is improved by 1.2%, and the highest classification accuracy is 94.16%. In the testing stage, for a segment of the broiler sound signal collected in the broiler captivity area, the combinations of the start frames and end frames of multiple sound types in the broiler sound signal are obtained through signal filtering, sub-frame processing, endpoint detection, and other steps. Thirty sound features are extracted from each frame signal to form the data set to be predicted. The optimal classification model is used to predict the labels of each piece of data in the data set to be predicted. By performing majority voting processing on the predicted labels of the data combination corresponding to each sound type, the common labels are obtained; that is, the predicted types are obtained. On this basis, the definition of recognition accuracy for broiler sound signals is proposed. The test results show that the classification accuracy achieved by the optimal classification model on the data set to be predicted is 93.57%, and the recognition accuracy achieved on the multiple segments of the broiler sound signals is 99.12%.


Assuntos
Algoritmos , Galinhas , Animais , Som , Processamento de Sinais Assistido por Computador
13.
Viruses ; 14(10)2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36298739

RESUMO

MicroRNAs (miRNAs) could regulate various biological processes. Nervous necrosis virus (NNV) is one of the primary germs of the Humpback grouper (Cromileptes altivelis), a commercial fish of great importance for Asian aquaculture. However, there is limited available information on the host-virus interactions of C. altivelis. miRNAs have been shown to play key roles in the host response to infection by a variety of pathogens. To better understand the regulatory mechanism of miRNAs, we constructed miRNA transcriptomes and identified immune-related miRNAs of C. altivelis spleen in response to NNV infection. Reads from the three libraries were mapped onto the Danio rerio reference genome. As a result, a total of 942 mature miRNAs were determined, with 266 known miRNAs and 676 novel miRNAs. Among them, thirty-two differentially expressed miRNAs (DEmiRs) were identified compared to the PBS control. These DEmiRs were targeted on 895 genes, respectively, by using miRanda v3.3a. Then, 14 DEmiRs were validated by qRT-PCR and showed consistency with those obtained from high-throughput sequencing. In order to study the relationship between viral infection and host miRNA, a cell line from C. altivelis brain (CAB) was used to examine the expressions of five known DEmiRs (miR-132-3p, miR-194a, miR-155, miR-203b-5p, and miR-146) during NNV infection. The results showed that one miRNA, cal-miRNA-155, displayed significantly increased expression in response to the virus infection. Subsequently, it was proved that overexpression of cal-miR-155 enhanced cell apoptosis with or without NNV infection and inhibited virus replication in CAB cells. Oppositely, the cal-miRNA-155 inhibitor markedly suppressed apoptosis in CAB cells. The results of the apoptosis-related genes mRNA expression also showed the regulation of cal-miR-155 on the apoptosis process in CAB cells. These findings verify that miR-155 might exert a function as a pro-apoptotic factor in reply to NNV stimulation in CAB cells and help us further study the molecular mechanisms of the pathogenesis of NNV in C. altivelis.


Assuntos
Bass , MicroRNAs , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Bass/genética , Bass/metabolismo , Perfilação da Expressão Gênica , Replicação Viral , Transcriptoma , RNA Mensageiro , Apoptose/genética , Necrose
14.
Angew Chem Int Ed Engl ; 61(43): e202205851, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-35929575

RESUMO

Coordination-driven self-assembly has led to the formation of various aesthetical polyhedrons and compounds with advanced functions. Whereas two-dimensional supramolecules with complex and giant skeletons are plentiful, the constructions of polyhedrons are limited by using basic polygons as the panels. Herein, we report the modular synthesis of a tessellated triangle and tessellated octahedron with metal-organic modules as the panels and formed via template-driven self-assembly. These architectures have diameters on the order of 10.9 nm and molecular weights greater than 84 kDa. Interestingly, fiber and spherical-like nanostructures could be formed from the tessellated triangles and octahedrons, respectively, through hierarchical self-assembly. In addition, after hybridization with carbon nanotubes, the supramolecules exhibit electrochemical reduction activity for CO2 to CO.

15.
Diagnostics (Basel) ; 12(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35626253

RESUMO

Purpose: To compare the reliability and performance of Supersonic shear wave elastography (S-SWE) and Toshiba shear wave elastography (T-SWE) in the diagnosis of biliary atresia (BA) and assessment of liver fibrosis among jaundiced infants suspected of BA. Material and Methods: A total of 35 patients with suspected BA who underwent both S-SWE and T-SWE examinations were prospectively included. Diagnostic performances of S-SWE and T-SWE in identifying BA were evaluated. The correlation between two types of SWE values and histological liver fibrosis stages by Metavir scores were investigated in 21 patients with pathology results. The intraclass correlation coefficients (ICCs) were calculated in 16 patients for inter- and intra-observer agreement. The area under the receiver operating characteristic curve (AUC) analysis was compared using a DeLong test. Results: There were 22 patients with BA and 13 patients without BA. The diagnostic performance of S-SWE was comparable to that of T-SWE (AUC 0.895 vs. 0.822, p = 0.071) in diagnosing BA. The AUCs of S-SWE in predicting liver fibrosis stages were from 0.676 to 1.000 and showed no statistical differences from that of T-SWE (from 0.704 to 1.000, all p > 0.05). T-SWE provided higher inter-operator agreement (ICC 0.990) and intra-operator agreement (ICCs 0.966−0.993), compared with that of S-SWE in a previous study (ICC 0.980 for inter-operator and 0.930−0.960 for intra-operator). Conclusions: For infants suspected of BA, T-SWE had good performances in the diagnosis of BA and the assessment of liver fibrosis compared with S-SWE. Furthermore, T-SWE showed higher measurement reproducibility than S-SWE.

16.
Sensors (Basel) ; 22(9)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35591257

RESUMO

Existing material identification for loose particles inside sealed relays focuses on the selection and optimization of classification algorithms, which ignores the features in the material dataset. In this paper, we propose a feature optimization method of material identification for loose particles inside sealed relays. First, for the missing value problem, multiple methods were used to process the material dataset. By comparing the identification accuracy achieved by a Random-Forest-based classifier (RF classifier) on the different processed datasets, the optimal direct-discarding method was obtained. Second, for the uneven data distribution problem, multiple methods were used to process the material dataset. By comparing the achieved identification accuracy, the optimal min-max standardization method was obtained. Then, for the feature selection problem, an innovative multi-index-fusion feature selection method was designed, and its superiority was verified through several tests. Test results show that the identification accuracy achieved by RF classifier on the dataset was improved from 59.63% to 63.60%. Test results of ten material verification datasets show that the identification accuracies achieved by RF classifier were greatly improved, with an average improvement of 3.01%. This strongly promotes research progress in loose particle material identification and is an important supplement to existing loose particle detection research. This is also the highest loose particle material identification accuracy achieved to in aerospace engineering, which has important practical value for improving the reliability of aerospace systems. Theoretically, it can be applied to feature optimization in machine learning.


Assuntos
Algoritmos , Aprendizado de Máquina , Reprodutibilidade dos Testes
17.
Org Biomol Chem ; 20(18): 3747-3754, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35448901

RESUMO

α-Branched heteroaryl amines are prevalent motifs in drugs and are typically prepared through C-N bond formation. In contrast, C-C bond-forming approaches to branched amines may dramatically expand available chemical space but are rarely pursued in parallel format due to a lack of established library protocols. Methods for the synthesis of α-branched heteroaryl amines via aldimine addition have been evaluated for compatibility with parallel synthesis. In situ activation of aliphatic carboxylic acids as redox-active esters enables Zn-mediated decarboxylative radical imine addition to access aliphatic-branched heterobenzylic amines. In situ activation of (hetero)aryl bromides via Li-halogen exchange enables heteroaryl-lithium addition to imines to access (hetero)benzhydryl amines. Condensation of heteroaryl amines with heteroaryl aldehydes provides aldimines which may be intercepted with aryl Grignard reagents to provide modular access to (hetero)benzhydryl amines. These protocols minimize synthetic step count and maximize accessible design space, enhancing access to α-branched heteroaryl amines for medicinal chemistry.


Assuntos
Aminas , Química Farmacêutica , Aldeídos/química , Aminas/química , Ácidos Carboxílicos , Iminas/química
18.
Pediatr Radiol ; 52(6): 1075-1085, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35234988

RESUMO

BACKGROUND: Percutaneous ultrasound (US)-guided cholecystocholangiography is effective in diagnosing biliary atresia for infants with a gallbladder >1.5 cm in length on US. However, whether it is still effective for other types of gallbladders needs further clarification. OBJECTIVE: To evaluate the diagnostic performance and safety of percutaneous US-guided cholecystocholangiography combined with liver biopsy in children with suspected biliary atresia and with different types of gallbladders on US. MATERIALS AND METHODS: Sixty-five infants were referred for percutaneous US-guided cholecystocholangiography with microbubbles and liver biopsy after an equivocal (n=39) or highly suspected (n=26) US diagnosis of biliary atresia. Two radiologists evaluated US and percutaneous US-guided cholecystocholangiography images in consensus. One pathologist independently evaluated liver specimens. We used the unpaired t-test, Mann-Whitney U test and chi-square test to analyze the data. RESULTS: Of the 65 infants, 59 (90.8%) underwent a successful percutaneous US-guided cholecystocholangiography, with both sensitivity and specificity of 100%. All six infants for whom puncture failed had contracted gallbladders. The sensitivity and specificity of liver biopsy in the diagnosis of biliary atresia were 89.7% (26/29) and 83.3% (30/36), respectively. When percutaneous US-guided cholecystocholangiography and liver biopsy were combined, all infants gained correct diagnosis, and in 35 infants (97.2%, 35/36) biliary atresia could be excluded without intraoperative cholangiography. Twenty-two of 65 infants (33.8%) had fluid collections around the liver related to puncture. None of these complications needed treatment. CONCLUSION: Percutaneous US-guided cholecystocholangiography combined with liver biopsy appears safe and effective for excluding or confirming biliary atresia in cholestatic infants with a dilated gallbladder on US.


Assuntos
Atresia Biliar , Colestase , Atresia Biliar/complicações , Atresia Biliar/diagnóstico por imagem , Biópsia , Criança , Diagnóstico Diferencial , Humanos , Lactente , Fígado/diagnóstico por imagem , Fígado/patologia , Microbolhas , Ultrassonografia de Intervenção
20.
Animals (Basel) ; 11(8)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34438695

RESUMO

Broiler sounds can provide feedback on their own body condition, to a certain extent. Aiming at the noise in the sound signals collected in broiler farms, research on evaluating the filtering methods for broiler sound signals from multiple perspectives is proposed, and the best performer can be obtained for broiler sound signal filtering. Multiple perspectives include the signal angle and the recognition angle, which are embodied in three indicators: signal-to-noise ratio (SNR), root mean square error (RMSE), and prediction accuracy. The signal filtering methods used in this study include Basic Spectral Subtraction, Improved Spectral Subtraction based on multi-taper spectrum estimation, Wiener filtering and Sparse Decomposition using both thirty atoms and fifty atoms. In analysis of the signal angle, Improved Spectral Subtraction based on multi-taper spectrum estimation achieved the highest average SNR of 5.5145 and achieved the smallest average RMSE of 0.0508. In analysis of the recognition angle, the kNN classifier and Random Forest classifier achieved the highest average prediction accuracy on the data set established from the sound signals filtered by Wiener filtering, which were 88.83% and 88.69%, respectively. These are significantly higher than those obtained by classifiers on data sets established from sound signals filtered by other methods. Further research shows that after removing the starting noise in the sound signal, Wiener filtering achieved the highest average SNR of 5.6108 and a new RMSE of 0.0551. Finally, in comprehensive analysis of both the signal angle and the recognition angle, this research determined that Wiener filtering is the best broiler sound signal filtering method. This research lays the foundation for follow-up research on extracting classification features from high-quality broiler sound signals to realize broiler health monitoring. At the same time, the research results can be popularized and applied to studies on the detection and processing of livestock and poultry sound signals, which has extremely important reference and practical value.

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