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1.
Sci Rep ; 14(1): 8373, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600262

RESUMO

The spatial response mechanism of hydrology and water quality of large river-connected lakes is very complicated. In this study, we developed a spatial response analysis method that couples wavelet correlation analysis (WTC) with self-organizing maps (SOM), revealing the spatial response and variation of water level and water quality in Poyang Lake, China's largest river-connected lake, over the past decade. The results show that: (1) there was significant spatial heterogeneity in water level and quality during the dry seasons (2010-2018) compared to other hydrological stages. (2) We identified a more pronounced difference in response of water level and quality between northern and southern parts of Poyang Lake. As the distance increases from the northern lake outlet, the impact of rising water levels on water quality deterioration intensified during the dry seasons. (3) The complex spatial heterogeneity of water level and quality response in the dry seasons is primarily influenced by water level fluctuations from the northern region and the cumulative pollutant entering the lake from the south, which particularly leads to the reversal of the response in the central area of Poyang Lake. The results of this study can contribute to scientific decision-making regarding water environment zoning management in large river-connected lakes amidst complex environment conditions.

2.
J Synchrotron Radiat ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656773

RESUMO

Synchrotron-radiation-based techniques are a powerful tool for the investigation of materials. In particular, the availability of highly brilliant sources has opened the possibility to develop techniques sensitive to dynamics at the atomic scale such as X-ray photon correlation spectroscopy (XPCS). XPCS is particularly relevant in the study of glasses, which have been often investigated at the macroscopic scale by, for example, differential scanning calorimetry. Here, we show how to adapt a Flash calorimeter to combine XPCS and calorimetric scans. This setup paves the way to novel experiments requiring dynamical and thermodynamic information, ranging from the study of the crystallization kinetics to the study of the glass transition in systems that can be vitrified thanks to the high cooling rates reachable with an ultrafast calorimeter.

3.
J Hazard Mater ; 471: 134289, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38663294

RESUMO

Wastewater resulting from hydrothermal liquefaction (HTL-AP) of biowaste is gaining attention as an emerging hazardous material. However, there is a lack of specific and systematic ecotoxicity studies on HTL-AP. This study addresses this gap by conducting acute toxicity tests on HTL-AP using typical aquatic species and integrating these results with predicted toxicity values from interspecies correlation estimation models to establish aquatic life criteria. HTL-AP exhibited significant toxicity with LC50 of 956.12-3645.4 mg/L, but demonstrated moderate toxicity compared to common freshwater pollutants like commercial microbicides, personal care products, and insect repellents. The resulting hazardous concentration for 5 % of species (HC5), the criterion maximum concentration, and the short-term water quality criteria for aquatic were 506.0, 253.0, and 168.7 mg/L, respectively. Notably, certain organisms like Misgurnus anguillicaudatus and Cipangopaludina chinensis showed high tolerance to HTL-AP, likely due to their metabolic capabilities on HTL-AP components. The significant decrease in HC5 values for some HTL-AP substances compared to pure compounds could indicate the synergistic inhibition effects among HTL-AP compositions. Furthermore, according to the established criteria, HTL-AP required significantly less diluted water (13 t) than carbendazim (1009 t) to achieve biosafety, indicating a safer release. This research establishes a preliminary water quality criterion for HTL-AP, offering a valuable reference for risk assessment and prediction in the utilization of HTL-AP within environmental contexts.

4.
Physiol Meas ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663434

RESUMO

OBJECTIVE: Electrocardiographic (ECG) lead misplacement can result in distorted waveforms and amplitudes, significantly impacting accurate interpretation. Although lead misplacement is a relatively low-probability event, with an incidence ranging from 0.4% to 4%, the large number of ECG records in clinical practice necessitates the development of an effective detection method. This paper aimed to address this gap by presenting a novel lead misplacement detection method based on deep learning models. APPROACH: We developed two novel lightweight deep learning model for limb and chest lead misplacement detection, respectively. For limb lead misplacement detection, two limb leads and V6 were used as inputs, while for chest lead misplacement detection, six chest leads were used as inputs. Our models were trained and validated using the Chapman database, with an 8:2 train-validation split, and evaluated on the PTB-XL, PTB, and LUDB databases. Additionally, we examined the model interpretability on the LUDB databases. Limb lead misplacement simulations were performed using mathematical transformations, while chest lead misplacement scenarios were simulated by interchanging pairs of leads. The detection performance was assessed using metrics such as accuracy, precision, sensitivity, specificity, and Macro F1-score. MAIN RESULTS: Our experiments simulated three scenarios of limb lead misplacement and nine scenarios of chest lead misplacement. The proposed two models achieved Macro F1-scores ranging from 93.42% to 99.61% on two heterogeneous test sets, demonstrating their effectiveness in accurately detecting lead misplacement across various arrhythmias. SIGNIFICANCE: The significance of this study lies in providing a reliable open-source algorithm for lead misplacement detection in ECG recordings. The source code is available at https://github.com/wjcai/ECG_lead_check.

5.
Int J Biol Macromol ; : 131684, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663695

RESUMO

Cracking, warping, and decaying stemming from wood's poor dimensional stability and durability are the most annoying issues of natural wood. There is an urgent need to address these issues, of which, sustainable and green chemical treatments are favorably welcomed. Herein, we developed a facile method through the incorporation of environmentally friendly biopolymer lignin into wood cells for wood dimensional stability and durability enhancement. Enzymatic hydrolysis lignin (EHL) was dissolved into various solvents followed by impregnation and drying to incorporate lignin into wood cells. Impregnation treatment was developed to incorporate into wood to improve its dimensional stability, durability, and micromechanics. The anti-swelling efficiency reached up to 99.4 %, the moisture absorption decreased down to 0.55 %, the mass loss after brown rot decay decreased to 7.22 %, and the cell wall elasticity as well as hardness increased 8.7 % and 10.3 %, respectively. Analyses acquired from scanning electron microscopy, fluorescent microscopy, and Raman imaging revealed that the EHL was successfully colonized in cell lumen as well as in cell walls, thus improved wood dimensional stability and durability. Moreover, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed EHL interaction with the cell wall components, thus the wood mechanical property was not impaired significantly, whereas nanoindentation data indicated even slight mechanical enhancement on the cell walls. This facile approach can improve the wood properties in multiple aspects and remarkably enhance the outdoor performance of modified wood products. In addition, using lignin as a natural modifying agent to improve wood performance will have a great positive impact on the environment.

6.
J Cheminform ; 16(1): 43, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622648

RESUMO

Multiple metrics are used when assessing and validating the performance of quantitative structure-activity relationship (QSAR) models. In the case of binary classification, balanced accuracy is a metric to assess the global performance of such models. In contrast to accuracy, balanced accuracy does not depend on the respective prevalence of the two categories in the test set that is used to validate a QSAR classifier. As such, balanced accuracy is used to overcome the effect of imbalanced test sets on the model's perceived accuracy. Matthews' correlation coefficient (MCC), an alternative global performance metric, is also known to mitigate the imbalance of the test set. However, in contrast to the balanced accuracy, MCC remains dependent on the respective prevalence of the predicted categories. For simplicity, the rest of this work is based on the positive prevalence. The MCC value may be underestimated at high or extremely low positive prevalence. It contributes to more challenging comparisons between experiments using test sets with different positive prevalences and may lead to incorrect interpretations. The concept of balanced metrics beyond balanced accuracy is, to the best of our knowledge, not yet described in the cheminformatic literature. Therefore, after describing the relevant literature, this manuscript will first formally define a confusion matrix, sensitivity and specificity and then present, with synthetic data, the danger of comparing performance metrics under nonconstant prevalence. Second, it will demonstrate that balanced accuracy is the performance metric accuracy calibrated to a test set with a positive prevalence of 50% (i.e., balanced test set). This concept of balanced accuracy will then be extended to the MCC after showing its dependency on the positive prevalence. Applying the same concept to any other performance metric and widening it to the concept of calibrated metrics will then be briefly discussed. We will show that, like balanced accuracy, any balanced performance metric may be expressed as a function of the well-known values of sensitivity and specificity. Finally, a tale of two MCCs will exemplify the use of this concept of balanced MCC versus MCC with four use cases using synthetic data. SCIENTIFIC CONTRIBUTION: This work provides a formal, unified framework for understanding prevalence dependence in model validation metrics, deriving balanced metric expressions beyond balanced accuracy, and demonstrating their practical utility for common use cases. In contrast to prior literature, it introduces the derived confusion matrix to express metrics as functions of sensitivity, specificity and prevalence without needing additional coefficients. The manuscript extends the concept of balanced metrics to Matthews' correlation coefficient and other widely used performance indicators, enabling robust comparisons under prevalence shifts.

7.
Cureus ; 16(3): e56279, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38623127

RESUMO

Introduction Dental school admissions in Pakistan traditionally rely on Higher Secondary School Certificate (HSSC), University of Health Sciences (UHS), and National Testing Service (NTS) scores, with limited research available on their predictive validity for dental school performance. This study aims to investigate the correlation between a student's first-year dental school performance and their HSSC, UHS, and NTS scores. Methods A total of 282 records, spanning the years 2016 to 2020, were obtained from a single private dental institution. The data included HSSC, UHS, and/or NTS scores, with the first professional examination results as the dependent variable. Statistical analysis was conducted using the Statistical Package for the Social Sciences (IBM SPSS Statistics for Windows, IBM Corp., Version 25.0, Armonk, NY), encompassing descriptive statistics, Pearson's correlation coefficients, and multiple regression analysis. Results Pearson's coefficients revealed weak to moderate positive correlations between the first professional examination and HSSC (r=0.209, p<.01), UHS (r=0.344, p<.01), and NTS (r=0.350, p<.01), all statistically significant at p < 0.01. Multiple regression analysis indicated that UHS scores contributed the highest explanatory power (R² = 0.146) in predicting first professional examination results. Conclusion A positive correlation between HSSC, UHS, and NTS scores with dental students' performance in the first professional examination is observed. However, the correlations are moderate, highlighting the importance of incorporating assessments that consider cognitive, behavioral, and skill-related aspects in admissions processes. Given the evolving landscape of dental education, these findings underscore the need for a holistic approach to identify candidates better equipped to serve the healthcare sector.

8.
BMC Pediatr ; 24(1): 261, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643075

RESUMO

OBJECTIVE: To explore the relationship between body mass index (BMI ) and the severity of tic disorders (TDs) in children 6-14 years old. METHODS: A total of 86 children diagnosed with TDs in a hospital between Jan. 2023 and Sept. 2023 were collected by convenient sampling method, and the general data and TD-specific data were collected and analyzed. RESULTS: Univariate analysis showed that patients with different Yale Global Tic Severity Scale (YGTSS) grades had statistically significant differences in age, BMI, residence, snacking pattern, weekly physical exercise frequency, weekly physical exercise time, and proportion of cesarean birth. Multiple linear regression analysis showed that the YGTSS score grades were related to BMI, snacking pattern, and cesarean birth of the patients. Correlation analysis revealed a positive correlation between BMI grades and the YGTSS score grades, with a higher BMI indicating more severe TDs. Predictive value evaluation showed that BMI, snacking pattern, and cesarean birth had predictive values for TD severity, and the highest value was found in the combined prediction. CONCLUSION: BMI, snacking pattern, and cesarean birth are of predictive values for the severity of TDs. In addition, BMI is positively correlated with the severity of TDs, and a higher BMI suggests more severe TDs.


Assuntos
Transtornos de Tique , Criança , Humanos , Adolescente , Transtornos de Tique/diagnóstico , Índice de Massa Corporal , Índice de Gravidade de Doença , Projetos de Pesquisa , Exercício Físico
9.
BMC Pregnancy Childbirth ; 24(1): 296, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643085

RESUMO

BACKGROUND: Ectopic pregnancies (EP) are a common pregnancy complication that's associated with significant morbidity and rarely mortality if not managed properly. Ultrasound examination forms the cornerstone of diagnosis of EP with some sonographic features occasionally not correlating with intraoperative findings. We set out to conduct an audit of EP managed surgically at our hospital for a 10-year period and discern the correlation and prediction of sonographic findings to intraoperative findings. METHODS: This study was designed as a Retrospective Observational Study based at the Aga Khan University Hospital (AKUH). Study population was all women admitted to AKUH with a diagnosis of ectopic pregnancy that was surgically managed between the period of January 1st 2011 to December 31st 2020. Analysis of data was done against a pre-set checklist. Descriptive statistics for continuous variables was calculated and tabulated in graphs and tables. SPSS version 22 was used for analysis of data. RESULTS: A total of 337 patients in this study had ultrasound findings. 99.7% (n = 336) of these patients had an intraoperatively confirmed EP. The commonest ultrasound finding was an adnexal mass in 97.1% (n = 309) of patients. These were confirmed surgically in 290 patients at the following locations: 76.6% (n = 222) were ampullary in location; 10.7% (n = 31) were fimbrial in location; 8.6%(n = 25) were isthmic in location; 2.4%(n = 7) were interstitial in location; 1%(n = 3) were abdominal in location; while 0.3% were located in the ovary(n = 1) or round ligament(n = 1) each. Interstitial EP on ultrasound were all (100%) confirmed in the same location intraoperatively, with ampullary EP also correlating fairly well with intraoperative location (75%). The distribution of location in the minor hemoperitoneum (HP) versus major HP groups were similar except for interstitial EP that increased from 1.4% in the minor HP group to 9.5% in the major HP group. CONCLUSION: In conclusion, ultrasonography still represents the best imaging modality for EP. The most common finding is usually an adnexal mass with no specific location. Most (99.7%) of the patients with this sonographic finding usually have a confirmed EP. Interstitial EP are the most well localized with ultrasound followed by ampullary EP. Furthermore, the presence of major (> 500mls) hemoperitoneum may act as an adjunct for diagnosis of an interstitial EP.


Assuntos
Laparoscopia , Complicações na Gravidez , Gravidez Intersticial , Gravidez , Humanos , Feminino , Hemoperitônio/etiologia , Ultrassonografia/efeitos adversos , Laparoscopia/métodos , Estudos Retrospectivos
10.
BMC Med Genomics ; 17(1): 95, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643142

RESUMO

NSUN2-intellectual disability syndrome, also known as intellectual disability type 5 (MRT5), is an autosomal recessive disorder that is characterized by intellectual disability (ID), postnatal growth retardation, dysmorphic facies, microcephaly, short stature, developmental delay, language impairment and other congenital abnormalities. The disease is caused by mutations in the NSUN2 gene, which encodes a tRNA cytosine methyltransferase that has an important role in spindle assembly during mitosis and chromosome segregation. In this study, we recruited a family that had two individuals with ID. Whole exome sequencing was performed to identify a homozygous frameshift variant (c.1171_1175delACCAT(p.Thr391fs*18*)) in NSUN2 (NM_017755.5) in the proband. The varint was confirmed as segregating in his affected brother and his parents by Sanger sequencing. The individuals that we described showed a similar dysmorphology profile to that associated with MRT5. To analyze the correlations between genotypes of NSUN2 and phenotypes of individuals with ID, we examined 17 variants and the associated phenotypes from 32 ID individuals in current and previous studies. We concluded that mutations in NSUN2 cause a wide range of phenotypic defects. Although some clinical manifestations were highly variable, the core phenotypes associated with NSUN2 mutations were dysmorphic facies, microcephaly, short stature, ID, growth restriction, language impairment, hypotonia and delayed puberty. Our study expands the genetic spectrum of NSUN2 mutations and helps to further define the genotype-phenotype correlations in MRT5.


Assuntos
Nanismo , Deficiência Intelectual , Transtornos do Desenvolvimento da Linguagem , Microcefalia , Malformações do Sistema Nervoso , Masculino , Humanos , Deficiência Intelectual/genética , Microcefalia/genética , Facies , Mutação , Fenótipo , China , Linhagem , Metiltransferases/genética
11.
Adv Lab Med ; 5(1): 66-74, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38634087

RESUMO

Objectives: Bone mass progressively increases to peak during childhood and adolescence, which determines future bone health. Bone formation-resorption processes are assessed using bone markers. However, studies on the impact of obesity on bone turnover markers at this age are limited, and results are inconsistent. The objective of this study was to examine the potential impact of overweight/obesity on bone metabolism. Methods: A study was performed to compare parameters of bone metabolism in 45 girls and boys with normal weight (controls) and in a group of 612 girls and boys with overweight/obesity (cases) from the Exergames study (University of Zaragoza). Ages ranged from 8 to 12 years. Results: Higher values of phosphorus and IGFBP-3 were observed in children with overweight/obesity, as compared to children with normal weight, (p=0.042) and (p=0.042), respectively. BAP, osteocalcin, magnesium, vitamin D and IGF-I concentrations were lower in the group with overweight/obesity, whereas calcium concentrations were higher in this group, although differences were not statistically significant. A negative correlation was found (r=-0.193) (p=0.049) between BAP and BMI. Conclusions: Although differences did not reach statistical significance, BAP and osteocalcin concentrations were lower in children with overweight/obesity. This added to the negative correlation found between BAP and MIC may demonstrate that overweight/obesity may negatively affect bone health already at a young age.

12.
J Agric Food Chem ; 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634619

RESUMO

Theaflavin-3,3'-digallate (TFDG) in black tea has a strong antioxidant capacity. However, its effect on diabetic liver and kidney injury and the underlying mechanisms remain unclear. In the present study, our findings indicated that TFDG administration effectively lowers the fasting blood glucose and serum lipid concentrations and enhances the functionality and cellular architecture of the liver and kidney in rats with diabetes. The data also showed that TFDG mitigates oxidative harm in the liver and kidney of rats afflicted with diabetes. Additionally, metformin combined with TFDG was significantly more effective in reducing blood glucose and oxidative stress. Further studies suggested that TFDG upregulates the Nrf2 signal pathway and circ-ITCH (hsa_circ_0001141) expression. Silencing of circ-ITCH by transfection of the interfering plasmid apparently reduces the effects of TFDG on the Nrf2 signal pathway and oxidative stress in high-glucose-treated hepatic and renal cells. In conclusion, the present study highlights the great potential of TFDG in ameliorating diabetic liver and kidney injury by up-regulating circ-ITCH to promote the Nrf2 signal pathway and provides a potential option for the prevention and treatment of diabetic complications.

13.
Cell Rep ; 43(4): 114081, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38581682

RESUMO

Narratives can synchronize neural and physiological signals between individuals, but the relationship between these signals, and the underlying mechanism, is unclear. We hypothesized a top-down effect of cognition on arousal and predicted that auditory narratives will drive not only brain signals but also peripheral physiological signals. We find that auditory narratives entrained gaze variation, saccade initiation, pupil size, and heart rate. This is consistent with a top-down effect of cognition on autonomic function. We also hypothesized a bottom-up effect, whereby autonomic physiology affects arousal. Controlled breathing affected pupil size, and heart rate was entrained by controlled saccades. Additionally, fluctuations in heart rate preceded fluctuations of pupil size and brain signals. Gaze variation, pupil size, and heart rate were all associated with anterior-central brain signals. Together, these results suggest bidirectional causal effects between peripheral autonomic function and central brain circuits involved in the control of arousal.


Assuntos
Encéfalo , Frequência Cardíaca , Humanos , Encéfalo/fisiologia , Feminino , Masculino , Frequência Cardíaca/fisiologia , Adulto , Pupila/fisiologia , Adulto Jovem , Nível de Alerta/fisiologia , Percepção Auditiva/fisiologia , Movimentos Sacádicos/fisiologia , Cognição/fisiologia , Sistema Nervoso Autônomo/fisiologia , Estimulação Acústica
14.
Biochim Biophys Acta Gen Subj ; 1868(6): 130618, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38621595

RESUMO

The oligomerization of proteins is an important biological control mechanism and has several functions in activity and stability of enzymes, structural proteins, ion channels and transcription factors. The determination of the relevant oligomeric states in terms of geometry (spatial extent), oligomer size (monomer or dimer or oligomer) and affinity (amounts of monomer, dimer and oligomer) is a challenging biophysical problem. Förster resonance energy transfer and fluorescence fluctuation spectroscopy are powerful tools that are sensitive to proximity and oligomerization respectively. Here it is proposed to combine image-based lifetime-detected Forster resonance energy transfer with image correlation spectroscopy and photobleaching to determine distances, oligomer sizes and oligomer distributions. Simulations for simple oligomeric forms illustrate the potential to improve the discrimination between different quaternary states in the cellular milieu.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Fotodegradação , Transferência Ressonante de Energia de Fluorescência/métodos , Multimerização Proteica , Estrutura Quaternária de Proteína , Humanos , Simulação por Computador
15.
Front Sports Act Living ; 6: 1385721, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38654754

RESUMO

Aim: The aim of this paper is to determine the relationship between the modified agility T-test (change of direction speed ability), 20-meter sprint test (linear speed ability), and countermovement jump test (vertical jumping performance) in U-14 and professional senior team sports players. Methods: The sample included 78 (59 female and 19 male) U-14 athletes (age 11.70 ± 1.33 years, height 153.00 ± 12.20 cm and body mass 47.10 ± 11.20 kg) and 43 (18 female and 25 male) senior professional athletes (age 24.80 ± 6.58 years, height 169.00 ± 9.13 cm and body mass 71.20 ± 15.10 kg). Both samples participated in different team sports including basketball, field hockey, and football. Participants underwent a series of tests to assess their speed, change of direction speed, and explosive power. Speed assessments involved 20-meter sprints (sec), while change of direction speed was measured using the modified agility T-test (sec). Explosive power was evaluated through countermovement jumps (CMJ), where concentric mean force (N), concentric peak force (N), concentric peak velocity (m/s), eccentric peak force (N), jump height (cm), peak power (W), peak power/BM (W/kg), RSI (m/s) and vertical velocity (m/s) were determined. Pearsons product moment-correlation coefficient (r) served to determine correlations and linear regression was conducted to explain the relationship between the dependent variable (CODS) and independent variables (S20 m and CMJ). The level of statistical significance was set at p < 0.05 and the confidence interval was 95%. Results: The Pearson product-moment correlation analysis in the U-14 athletes indicated no correlation (r = 0.11, p = 0.34) between the 20-meter linear sprint speed and the modified change of direction T-test. Additionally, the results revealed that 4 out of 10 CMJ values showed a significant moderate correlation (r = 0.3, p < 0.05) between CMJ and the modified change of direction T-test. In contrast, senior players exhibited statistically significant correlations in all variables. A significant correlation (r = 0.90, p = 0.01) was found between 20-meter linear sprint speed and the modified change of direction T-test, while CMJ values showed a range of correlations from moderate to large. In both competitive categories, according to the linear regression model, only linear sprint speed over 20-meters significantly explained (p < 0.05) the CODS speed ability, while the other CMJ parameters did not reach the significance level (p > 0.05). Conclusion: The study emphasized the influence of explosive power performance (CMJ) and linear speed (S20 m) on agility (CODS) within the sample, particularly among professional senior team sports players. These findings indicate that agility, linear sprinting, and jumping abilities may share common underlying factors.

16.
Heliyon ; 10(8): e29666, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38655361

RESUMO

Additive manufacturing technology has advanced beyond creating optimized features, from strengthening materials to make them lightweight to fabricating multi-material combinations that offer functionalities beyond the capabilities of individual materials. In this study, a lamination method for laser-directed energy deposition (LDED) is developed to achieve dense multi-material features, and a design that combines different and dissimilar materials is developed. To evaluate these novel developments, two materials-AISI 316L stainless steel and Inconel 625-are introduced. Tensile specimens, fabricated via multi-material additive manufacturing using LDED, are subjected to tensile tests that are recorded on video for digital image correlation. After the tests, fracture surface analyses of the fractured specimens are performed via scanning electron microscopy, and optical monitoring analyses are performed on the specimens that are not subjected to the tensile tests. The results indicate that the specimens demonstrate varied mechanical properties due to the influence of lamination direction and order, which affect the formation of critical cracks and pores.

17.
Front Aging Neurosci ; 16: 1369493, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659706

RESUMO

Background: We aimed to examine the association between blood levels of Branched-chain amino acids (BCAAs) - specifically isoleucine, leucine, and valine - and the susceptibility to three neurodegenerative disorders: dementia, Alzheimer's disease (AD), and Parkinson's disease (PD). Methods: Based on data from the UK Biobank, a Cox proportional hazard regression model and a dose-response relationship were used to analyze the association between BCAAs and the risks of dementia, AD, and PD. We also generated a healthy lifestyle score and a polygenic risk score. Besides, we conducted a sensitivity analysis to ensure the robustness of our findings. Results: After adjusting for multiple covariates, blood concentrations of isoleucine, leucine, and valine were significantly associated with a reduced risk of dementia and AD. This association remained robust even in sensitivity analyses. Similarly, higher levels of isoleucine and leucine in the blood were found to be associated with an increased risk of PD, but this positive correlation could potentially be explained by the presence of covariates. Further analysis using a dose-response approach revealed that a blood leucine concentration of 2.14 mmol/L was associated with the lowest risk of dementia. Conclusion: BCAAs have the potential to serve as a biomarker for dementia and AD. However, the specific mechanism through which BCAAs are linked to the development of dementia, AD, and PD remains unclear and necessitates additional investigation.

18.
J Biomed Opt ; 29(4): 046008, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659998

RESUMO

Significance: Optical imaging is a non-invasive imaging technology that utilizes near-infrared light, allows for the image reconstruction of optical properties like diffuse and absorption coefficients within the tissue. A recent trend is to use signal processing techniques or new light sources and expanding its application. Aim: We aim to develop the reflective optical imaging using the chaotic correlation technology with chaotic laser and optimize the quality and spatial resolution of reflective optical imaging. Approach: Scattering medium was measured using reflective configuration in different inhomogeneous regions to evaluate the performance of the imaging system. The accuracy of the recovered optical properties was investigated. The reconstruction errors of absorption coefficients and geometric centers were analyzed, and the feature metrics of the reconstructed images were evaluated. Results: We showed how chaotic correlation technology can be utilized for information extraction and image reconstruction. This means that a higher signal-to-noise ratio and image reconstruction of inhomogeneous phantoms under different scenarios successfully were achieved. Conclusions: This work highlights that the peak values of correlation of chaotic exhibit smaller reconstruction error and better reconstruction performance in optical imaging compared with reflective optical imaging with the continuous wave laser.


Assuntos
Processamento de Imagem Assistida por Computador , Lasers , Imagem Óptica , Imagens de Fantasmas , Espalhamento de Radiação , Imagem Óptica/métodos , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-Ruído , Dinâmica não Linear , Algoritmos , Desenho de Equipamento
19.
Heliyon ; 10(8): e29525, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644850

RESUMO

In this work, a workflow has been developed for the generation of surrogate metamodels to predict and evaluate failure with a confidence above 95 % in initial service conditions of high-performance cylindrical vessels manufactured in composites by Roll Wrapping technology. Currently, there is no specific testing standardization for this type of vessel and to fill this gap probabilistic numerical models were developed, performed by the Finite Element Method, fed with the material characteristics obtained experimentally by 2D digital image correlation from flat specimens. From the initial numerical model, a surrogate metamodel was generated by stochastic approximations. Once the metamodels were obtained by robust engineering, an experimental ring-ring tensile test was developed under service conditions and deformations were measured by high-precision 3D digital image correlation. Parametric and robust tests showed that the results of the metamodel did not show statistically significant differences, with errors in the rupture part of less than 2 % with respect to the results obtained in the test, being proposed as a basis for new test procedures.

20.
bioRxiv ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38645002

RESUMO

High-amplitude co-activation patterns are sparsely present during resting-state fMRI but drive functional connectivity1-5. Further, they resemble task activation patterns and are well-studied3,5-10. However, little research has characterized the remaining majority of the resting-state signal. In this work, we introduced caricaturing-a method to project resting-state data to a subspace orthogonal to a manifold of co-activation patterns estimated from the task fMRI data. Projecting to this subspace removes linear combinations of these co-activation patterns from the resting-state data to create Caricatured connectomes. We used rich task data from the Human Connectome Project (HCP)11 and the UCLA Consortium for Neuropsychiatric Phenomics12 to construct a manifold of task co-activation patterns. Caricatured connectomes were created by projecting resting-state data from the HCP and the Yale Test-Retest13 datasets away from this manifold. Like caricatures, these connectomes emphasized individual differences by reducing between-individual similarity and increasing individual identification14. They also improved predictive modeling of brain-phenotype associations. As caricaturing removes group-relevant task variance, it is an initial attempt to remove task-like co-activations from rest. Therefore, our results suggest that there is a useful signal beyond the dominating co-activations that drive resting-state functional connectivity, which may better characterize the brain's intrinsic functional architecture.

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