Abstract
With the development of smart grid and energy Internet, power electronic transformer has become one of the key equipment in power system. Its characteristic research and structure design ...have become a hot topic in related research fields. In order to take into account, the access of traditional AC motor system and renewable energy system, a three-stage power electronic transformer simulation model based on Simulink platform is built in this paper, and the key characteristics are analyzed and verified. With the application of power electronic transformer, the AC voltage can be adjusted quickly, and the AC / DC interface can be taken into account in the transmission system.
There is a complex high-dimensional nonlinear mapping relationship between the compressive strength of High-Performance Concrete (HPC) and its components, which has great influence on the accurate ...prediction of compressive strength. In this paper, an efficient robust software calculation strategy combining BP Neural Network (BPNN), Support Vector Machine (SVM) and Genetic Algorithm (GA) is proposed for the prediction of compressive strength of HPC. 8 features were extracted from the previous literature, and a compressive strength database containing 454 sets of data was constructed. The model was trained and tested, and the performance of 4 Machine Learning (ML) models, namely BPNN, SVM, GA-BPNN and GA-SVM, was compared. The results show that the coupled model is superior to the single model. Moreover, because GA-SVM has better generalization ability and theoretical basis, its convergence speed and prediction accuracy are better than GA-BPNN. Then Grey Relational Analysis (GRA) and Shapley analysis were used to verify the interpretability of the GA-SVM model, which showed that the water-binder ratio had the most significant influence on the compressive strength. Finally, the combination of multiple input variables to evaluate the compressive strength supplemented this research, and again verified the significant influence of water-binder ratio, providing reference value for subsequent research.
Abstract Background Consumption of low-calorie sweeteners (LCSs) has increased markedly during the past several decades, yet the prevalence of LCS consumption in recent years is currently unknown. ...Objective The aim of this study was to describe LCS consumption in the United States and to characterize consumption by sociodemographic subgroups, source, frequency, eating occasion, and location. Design Cross-sectional study using National Health and Nutrition Examination Survey data from 2009 to 2012. The prevalence of LCS consumption was assessed using two 24-hour dietary recalls, while the frequency (number of times per day), occasion (meal vs snack vs alone), and location of LCS consumption (at home vs away from home) was assessed using data from the one, in-person, 24-hour dietary recall. Participants National Health and Nutrition Examination Survey participants (2 years old or older) either in 2009-2010 (n=9,047) or in 2011-2012 (n=7,939). After excluding participants with implausible energy intake (n=44), the final sample size was 16,942. Main outcome measures The primary outcome was the proportion of individuals consuming one or more foods, beverages, or packets containing LCSs during at least one of their two dietary recalls. Statistical analyses performed Data were weighted to provide national estimates and Stata frequency procedures for complex survey design were used for all analyses. Results Our findings were that 25.1% of children and 41.4% adults reported consuming LCSs. Most LCS consumers reported use once daily (80% of children, 56% of adults) and frequency of consumption increased with body weight in adults. LCS consumption was higher in females compared with males among adults, and in obese individuals, compared with overweight and normal-weight individuals. Individuals of non-Hispanic white race/ethnicity also had higher prevalence of consumption compared with non-Hispanic blacks and Hispanics and those in the highest tertile of income had higher LCS consumption compared with individuals of middle or low income across LCS product categories in adults, and for LCS beverages and LCS foods in children. Most LCS consumers reported consuming LCS with meals (64% of adults, 62% of children) and the majority of LCS consumption occurred at home (71% and 72% among adults and children, respectively). Conclusions LCS consumption is highly prevalent in the United States, among both children and adults. Well-controlled, prospective trials are required to understand the health impact of this widespread LCS exposure.
A broad family of the nowadays studied low-dimensional systems, including 2D materials, demonstrate many fascinating properties, which however depend on the atomic composition as well as on the ...system dimensionality. Therefore, the studies of the electronic correlation effects in the new 2D materials is of paramount importance for the understanding of their transport, optical and catalytic properties. Here, by means of electron spectroscopy methods in combination with density functional theory calculations we investigate the electronic structure of a new layered van der Waals FePX3 (X: S, Se) materials. Using systematic resonant photoelectron spectroscopy studies we observed strong resonant behavior for the peaks associated with the 3dn-1 final state at low binding energies for these materials. Such observations clearly assign FePX3 to the class of Mott–Hubbard type insulators for which the top of the valence band is formed by the hybrid Fe-S/Se electronic states. These observations are important for the deep understanding of this new class of materials and draw perspectives for their further applications in different application areas, like (opto)spintronics and catalysis.
The dynamic HIV/AIDS epidemic significantly impacts China, particularly affecting injection drug users (IDUs), former plasma donors (FPDs), men who have sex with men (MSM), and those engaging in ...high-risk heterosexual behavior (HRHB). This study specifically focuses on identifying the risk factors and influences that drive the spread of HIV among these population groups by performing a comprehensive analysis of contact histories of individuals diagnosed with HIV.
Data for this research were gathered from China's HIV/AIDS Comprehensive Response Information Management System (CRIMS). Contact histories were described using bar and venn diagram. Trend in engaging in HBRB among MSM were identify potential change using the Cochran-Armitage test. Logistic regression was employed to analyze the factors influencing HBRB in MSM.
From 1989 through to 2022, a total of 1,457,218 individuals aged 15 years or older in China, who reported being infected with HIV, indicated they had one or more types of contact histories including injecting drug use, male homosexual behavior, commercial plasma donation, and high-risk heterosexual behavior. Among these, 97.0% reported a single type of contact history, while 3.0% reported having multiple contact histories. Of those with multiple contact histories, 98.0% (42,258 individuals) had engaged in HRHB. Among all HIV-infected IDUs, MSM, and FPDs, their respective proportions of engagement in HRHB were 11.8%, 5.7% and 6.2%. Prior to 2012, most were reported to be IDUs; however, subsequent to this, most reported being MSM. Factors that heightened the risk of engaging in HRHB among HIV-infected MSM included being of age between 25-34 years adjusted odds ratio (AOR) = 1.29 or 35-44 years (AOR = 1.22), marital status such as being married (AOR = 1.23) or being divorced/widowed (AOR = 1.17), belonging to an ethnic minority (AOR = 1.29), receiving diagnosis in hospitals (AOR = 1.81), residing in rural areas (AOR = 1.12), among others. However, the risk of HRHB decreased when age ≥ 55 years (55-64 years: AOR = 0.82; ≥ 65 years: AOR = 0.64).
The potential for HIV transmission among diverse populations is substantial. As such, it is imperative that strategies are implemented to mitigate the propagation of HIV to the general populace via heterosexual intercourse.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
While numerous studies have highlighted an increased prevalence of depression in individuals with narcolepsy, their conclusions are often clouded by potential confounding factors, leaving the causal ...relationship uncertain. This study posits that narcolepsy might heighten the risk of depression and employs a two-sample Mendelian randomization analysis to investigate this hypothesis.
Summary statistics were obtained from genome-wide association studies databases and performed a two-sample MR analysis. The inverse-variance weighted method was employed as the primary approach to evaluate causality. Additionally, supplementary methods were conducted, including MR-Egger, simple median, maximum likelihood, weighted median, penalized weighted median, and weighted mode, to complement the IVW results. Finally, sensitivity analyses were undertaken to assess heterogeneity, horizontal pleiotropy, and stability of the results.
The inverse-variance weighted analysis revealed an odds ratio of 1.055 with a 95% confidence interval of 1.015 to 1.097, indicating a significant positive association between narcolepsy and depression. Although significant heterogeneity was observed (Q = 56.22, p = 0.0005), no evidence of horizontal pleiotropy was detected (intercept = −0.00027, p = 0.69). Results from the additional methods were in agreement with those obtained from the inverse-variance weighted analysis. The reverse causality of depression on narcolepsy was not detected (p = 0.11).
This study suggests a potential causal association between narcolepsy and depression. While the findings offer insights into this relationship, they should be interpreted with caution, especially considering the limitations of the data. Further research is needed to better understand the underlying mechanisms and to explore potential interventions.
•Causal link found: Narcolepsy associated with increased depression risk.•Mendelian randomization reveals narcolepsy-depression connection.•Robust MR approach supports narcolepsy's role in depression.•Genetic evidence supports narcolepsy's influence on depression.•Key study: Narcolepsy's impact on depression warrants further inquiry.
Socioeconomic status may influence childhood obesity prevalence and children's fitness level. The purpose of this study was to assess the association between family income and children's physical ...fitness level and obesity prevalence for 8 racial/ethnic groups.
Data for 1,617,400 fifth-, seventh-, and ninth-grade children who took a physical fitness test from 2010 through 2012 in California were used in this cross-sectional study. Multiple linear and log-binomial regressions were used to test whether low family income (as indicated by eligibility for National School Lunch Program) was associated with physical fitness level or obesity prevalence. Differences were tested by race/ethnicity while adjusting for age and sex. Fitness score was measured on a scale from 0 (least healthy) to 6 (most healthy).
Average fitness score was 4.45 (standard deviation, 1.47). Prevalence of obesity was 20.3%, and 56% of children were classified as having lower family income. Lower family income (vs higher) was associated with lower fitness score (coefficient = -0.57; 95% confidence interval CI, -0.62 to -0.53). Lower-income children had higher prevalence of obesity (relative risk = 1.81; 95% CI, 1.72-1.89) compared with higher-income children. These inverse associations were seen among American Indian, Asian, Pacific Islander, Filipino, Hispanic/Latino, African American, and white children and among children who were identified as being of 2 or more races/ethnicities.
Children with lower family incomes tend to have less healthy physical fitness status and have higher risk of obesity than children with higher family incomes. This information can be used to help set policies and provide programs aimed at improving fitness and decreasing obesity risk among low-income children.
Liquid biopsy has been widely researched for early diagnosis, prognostication and disease monitoring in lung cancer, but there is a need to investigate its clinical utility for early-stage non-small ...cell lung cancer (NSCLC).
We performed a meta-analysis and systematic review to evaluate diagnostic and prognostic values of liquid biopsy for early-stage NSCLC, regarding the common biomarkers, circulating tumor cells, circulating tumor DNA (ctDNA), methylation signatures, and microRNAs. Cochrane Library, PubMed, EMBASE databases, ClinicalTrials.gov, and reference lists were searched for eligible studies since inception to 17 May 2022. Sensitivity, specificity and area under the curve (AUC) were assessed for diagnostic values. Hazard ratio (HR) with a 95% confidence interval (CI) was extracted from the recurrence-free survival (RFS) and overall survival (OS) plots for prognostic analysis. Also, potential predictive values and treatment response evaluation were further investigated.
In this meta-analysis, there were 34 studies eligible for diagnostic assessment and 21 for prognostic analysis. The estimated diagnostic values of biomarkers for early-stage NSCLC with AUCs ranged from 0.84 to 0.87. The factors TNM stage I, T1 stage, N0 stage, adenocarcinoma, young age, and nonsmoking contributed to a lower tumor burden, with a median cell-free DNA concentration of 8.64 ng/ml. For prognostic analysis, the presence of molecular residual disease (MRD) detection was a strong predictor of disease relapse (RFS, HR, 4.95; 95% CI, 3.06-8.02; p < 0.001) and inferior OS (HR, 3.93; 95% CI, 1.97-7.83; p < 0.001), with average lead time of 179 ± 74 days between molecular recurrence and radiographic progression. Predictive values analysis showed adjuvant therapy significantly benefited the RFS of MRD + patients (HR, 0.27; p < 0.001), while an opposite tendency was detected for MRD - patients (HR, 1.51; p = 0.19). For treatment response evaluation, a strong correlation between pathological response and ctDNA clearance was detected, and both were associated with longer survival after neoadjuvant therapy.
In conclusion, our study indicated liquid biopsy could reliably facilitate more precision and effective management of early-stage NSCLC. Improvement of liquid biopsy techniques and detection approaches and platforms is still needed, and higher-quality trials are required to provide more rigorous evidence prior to their routine clinical application.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Identifying modifying protective factors to promote healthy aging is of utmost public health importance. The frailty index (FI) reflects the accumulation of health deficits and is one widely used ...method to assess health trajectories in aging. Adherence to a Mediterranean-type diet (MTD) has been associated with favorable health trajectories. Therefore, this study explored whether adherence to a MTD is negatively associated with FI in the InCHIANTI study. Participants (
= 485) included individuals over 65 years of age at baseline with complete data over a follow-up period of 10 years. MTD was computed on a scale of 0-9 and categorized based on these scores into three groups of low (≤3), medium (4-5), and high (≥6) adherence. Being in a high or medium adherence group was associated with 0.03 and 0.013 unit lower FI scores over the follow-up period, compared to the low adherence group. In participants with a low FI at baseline, being in a high or medium MTD-adherence group had 0.004 and 0.005 unit/year slower progression of FI compared to the low adherence group. These study results support adherence to a MTD as a protective strategy to maintain a lower FI.