Regression Coefficients Research Articles

The Distinction of Evaluation on Companies in Different Fields

This paper explores the variations in Return on Equity (ROE) and Price-to-Sales Ratio among publicly traded companies across different time periods and market capitalizations. The analysis employs Linear Regression and Correlation Coefficients to examine the relationships between ROE, Price-to-Sales Ratio, Market Capitalization, and economic conditions during these periods. The findings reveal that Price-to-Sales Ratio serves as a reliable indicator of a company's market capitalization. Furthermore, companies within the same industry exhibit substantial disparities in Market Capitalization, ROE, Price-to-Sales Ratio, Price-to-Earnings (P/E) Ratio, and PEG Index due to differing corporate strategies and backgrounds. For instance, in the new energy sector, both BYD and NIO display a negative correlation between market capitalization, while Tesla contradicts this trend. This discrepancy is attributed to internal factors such as asset composition, liabilities, and shareholder structure, which significantly influence a company's financial performance. The Market Capitalization of these new energy companies is predicted to rise due to global interest in AI technology, with technology companies being at the forefront of AI development. In the technology sector, companies like Google have solidified their positions by advancing AI concepts. New entrants, like Apple, combining Artificial Intelligence and Robotics, are gaining consumer support, indicating potential Market Cap. growth. The fashion industry also demonstrates distinctive strategies, with companies like NIKE, Adidas, and Anta focusing on sustainability and carbon neutrality. Therefore, future company evaluations should consider both financial indices and a company's long-term vision and sustainability practices to predict their future value effectively.

Knowledge of urinary incontinence among women 6 weeks to 1 year after delivery.

Urinary incontinence (UI) is common among postpartum women, but many do not seek medical help due to limited knowledge. Understanding the level of knowledge about UI in this population is essential for improving care-seeking behaviors and implementing targeted interventions. The objective was to examine knowledge regarding UI among postpartum women with UI within 6 weeks to 1 year after delivery. A cross-sectional study was conducted at obstetric clinic in two level-three grade A hospitals in Shenzhen, China, from January 2023 to June 2023. Women in their 6 weeks to 1 year after delivery with UI were asked to complete a questionnaire comprising three sections: (1) demographic variable; (2) International Consultation on Incontinence Questionnaire Short Form (ICIQ-UI SF); and (3) The Urinary Incontinence Quiz (UIQ). A total of 1228 women completed the questionnaire. Their mean UIQ score was 6.63 ± 3.51 (minimum = 2, maximum = 15), indicating the deficiency of UI knowledge among Chinese postpartum women. A total of 86.4% of participants experienced slight or moderate postpartum UI. The results of multivariate linear regression models for UIQ reveal significant independent associations between questionnaire scores and two variables: experience in pelvic floor muscle training (PFMT) (p < 0.001) and UI treatment in the past (p < 0.001). The overall model fit was R2 = 0.559 (p < 0.001). The regression coefficients for the experience in PFMT and UI treatment in the past were 2.301 and 4.916, respectively. However, no other discernible factors were identified to distinguish between those with and without adequate knowledge. Postpartum women with UI within 6 weeks to 1 year after delivery had poor knowledge of UI. Targeted educational interventions focusing on PFMTand early treatment for UI are essential.

Limb Volume Measurements: A Comparison of Circumferential Techniques and Optoelectronic Systems against Water Displacement

Background. Accurate measurements of limb volumes are important for clinical reasons. We aimed to assess the reliability and validity of two centimetric and two optoelectronic techniques for limb volume measurements against water volumetry, defined as the gold standard. Methods. Five different measurement methods were executed on the same day for each participant, namely water displacement, fixed-height (circumferences measured every 5 (10) cm for the upper (lower limb) centimetric technique, segmental centimetric technique (circumferences measured according to proportional height), optoelectronic plethysmography (OEP, based on a motion analysis system), and IGOODI Gate body scanner technology (which creates an accurate 3D avatar). Results. A population of 22 (15 lower limbs, 11 upper limbs, 8 unilateral upper limb lymphoedema, and 6 unilateral lower limb lymphoedema) participants was selected. Compared to water displacement, the fixed-height centimetric method, the segmental centimetric method, the OEP, and the IGOODI technique resulted in mean errors of 1.2, 0.86, −16.0, and 0.71%, respectively. The corresponding slopes (and regression coefficients) of the linear regression lines were 1.0002 (0.98), 1.0047 (0.99), 0.874 (0.94) and 0.9966 (0.99). Conclusion. The centimetric methods and the IGOODI system are accurate in measuring limb volume with an error of &lt;2%. It is important to evaluate new objective and reliable techniques to improve diagnostic and follow-up possibilities.

Effects of Land-Use Type and Salinity on Soil Carbon Mineralization in Coastal Areas of Northern Jiangsu Province

Sea level rise due to glacier melting caused by climate warming is a major global challenge, but the mechanism of the effect of salinity on soil carbon (C) mineralization in different land types is not clear. The pathways by which salinity indirectly affects soil carbon mineralization rates need to be investigated. Whether or not the response mode is consistent among different land-use types, as well as the intrinsic links and interactions between soil microbial resource limitation, environmental stress, microbial extracellular enzyme activity, and soil carbon mineralization, remain to be demonstrated. In this paper, three typical land-use types (wetland, forest, and agroforestry) were selected, and different salinity levels (0‰, 3‰, 6‰, and 32‰) were designed to conduct a 125-day laboratory incubation experiment to determine the soil CO2 release rate, soil physicochemical properties, and soil enzyme activities, and to correlate C mineralization with biotic and abiotic factors. A correlation analysis of soil physical and chemical properties, extracellular enzyme activities, and carbon mineralization rates was conducted to investigate their intrinsic linkages, and a multiple linear regression of C mineralization at different sites was performed to explore the variability of mineralization among different site types. Structural equation models were established in the pre- and post-incubation stages to study the pathways of soil C mineralization at different incubation times, and the mechanism of mineralization was further verified by enzyme stoichiometry. The results showed that, at the end of 125 days of incubation, the 32‰ salinity addition reduced the cumulative mineralization of forest and agroforestry types by 28.41% and 34.35%, respectively, compared to the 0‰ salinity addition. Soil C mineralization in the three different land-use types was highly correlated with the active C fractions of readily oxidizable C (ROC), dissolved organic C, and microbial biomass C (MBC) in the soil, with the standardized coefficients of multivariate linear regression reaching 0.67 for MBC in the wetland and −0.843 for ROC in the forest. Under long-term salinity additions, increased salinity would reduce the microbial respiratory quotient value by inhibiting β-glucosidase activity, thus indirectly affecting the rate of CO2 release. With added salinity, the mineralization of non-saline soil was more susceptible to the inhibitory effect of salinity, whereas the mineralization of salinized soil was more controlled by soil C pools.

The Effect of Tax Avoidance on Cost of Debt with Institutional Ownership as a Moderating Variable (Empirical Study of Energy Sector Companies Listed on The IDX 2020-2022)

This research aims to test the effect of tax avoidance on the cost of debt with institutional ownership as a moderating variable. In this research, tax avoidance is measured by the effective tax rate. The population in this research is energy sector companies listed on the Indonesia Stock Exchange for the 2020-2022 period. This type of research is quantitative research. The sample in this research was obtained using purposive sampling, namely selecting samples using predetermined criteria. Based on the purposive sampling method, 57 samples were obtained from 82 energy sector companies listed on the Indonesia Stock Exchange for the 2020-2022 period. The analytical methods used are simple linear regression analysis, Moderated Regression Analysis, partial test (t), and coefficient of determination test (R2) using the SPSS version 16 program. The results of this research show that tax avoidance has a significant negative influence on cost of debt. Institutional ownership can strengthen the tax avoidance and cost of debt variables.

The Influence of Parental Motivation on The Achievement of Senior High School Students

This study aimed to determine the significant relationship between parental motivation and achievement of senior high school students. A simple random sampling technique was used to include 56 respondents. Through non-experimental quantitative descriptive-correlational research technique, validated questionnaire, Mean, Pearson-Product Moment Correlation Coefficient (Pearson-r) and Simple Linear Regression; results showed that the level of parental motivation was high or oftentimes manifested. It was also found that the level of achievement was high or very satisfactory. There was a significant relationship between parental motivation and achievement. This implies that when parents show motivation towards their children’s education, the students tend to perform better academically. Accordingly, parental motivation significantly influences student’s achievement. It was recommended that future researchers broaden their scope beyond parental motivation and consider other influential factors on student achievement, such as peer influence, teaching quality, and personal motivation. Longitudinal and intervention studies were also recommended to be conducted.

Development and Validation of Novel HPLC Methods for Quantitative Determination of Vitamin D3 in Tablet Dosage Form

In the present work, an efficient isocratic HPLC method was developed for the precise and accurate estimation of vitamin D3 in tablet form. The chromatographic conditions comprised an L3 silica column (5 µm in particle size, 4.6 mm × 250 mm) with a mobile phase n-hexane/ethyl acetate (85:15 v/v) with a flow rate of 2.0 mL/min and a detection wavelength of 292 nm. The new methodology was validated for accuracy, precision, specificity, robustness, and quantification limits according to an official monograph of USP/BP and ICH guidelines. The peak areas of the six replicates of the homogeneous sample were recorded. The mean value obtained was 67,301, and the relative standard deviation (RSD) was 0.1741. The linearity and range were in the acceptable bounds, i.e., 0.999, which was calculated using regression line analysis. The results show that the method is truly acceptable as the RSD, as the flow rate was 0.81%, while for the mobile phase composition, it was 0.72%, which lies in the acceptable range. The limit of detection (LOD) and the limit of quantification (LOQ) values were 0.0539 µg/mL and 0.1633 µg/mL, respectively. The % RSD of the intra and inter-day precision of the method was deemed acceptable according to the international commission for harmonization guidelines. The developed method has potential to be used for the detection and quantification of vitamin D3 during routine analysis for tablets in dosage form.

Effect of physical frailty on maximum phonation time in community-dwelling older individuals who visited a neurology outpatient clinic.

Maximum phonation time (MPT) is used to assess speech and other oral rehabilitation-related issues. Various factors contribute to MPT decline in older individuals. Although the impact of physical frailty on MPT has been suggested, this has not been conclusively determined. To examine the relationship between MPT and physical frailty in community-dwelling individuals aged ≥60 years who were independently mobile. MPT-associated factors were investigated. This cross-sectional study analysed the clinical data of 122 patients (age [interquartile range]: 80.0 [74.0-83.0] years) without dementia who visited a neurology department between 1 February 2021 and 31 January 2023. Investigated factors included age, sex, weight, height, body mass index, smoking history, grip strength, functional independence measure, vital capacity, oral diadochokinesis, MPT and the Japanese Cardiovascular Health Study score. Physical frailty was assessed based on the total score from five items (weight loss, weakness, exhaustion, slowness and low physical activity). The relationship between MPT and physical frailty was examined using Spearman's rank correlation coefficient and hierarchical multiple regression analysis. The MPT was negatively correlated with age (r = -0.347, p < .01) and physical frailty (r = -0.681, p < .01) and positively correlated with vital capacity (r = 0.474, p < .01) and height (r = 0.248, p < .01). The hierarchical multiple regression analysis, conducted with MPT as the dependent variable, demonstrated that physical frailty (β = -.59, 95% confidence interval: -0.74 to 0.43, p < .001) had a strong influence on MPT. In older individuals, MPT is associated with physical frailty. When assessing MPT in clinical settings, it is advisable to perform a concurrent assessment of physical frailty.

Development and Validation of UV Spectroscopic method for the estimation of favipiravir in bulk and tablet dosage form

Simple, precise and accurate area under curve spectroscopic method has been developed and validated for the estimation of Favipiravir in bulk and pharmaceutical dosage form. The drug shows maximum absorption (λ max) at 361nm in 0.1N NaOH solution and Area under Curve [AUC] in absorption spectra were measured between the wavelength range 356 to 366nm which obeys Beer’s law in the concentration range of 2-10µg/ml. The linearity study carried and regression coefficient was found to be 0.9982 and it has showed good linearity, precision during this concentration range. The % recovery was found to be 98.6-101.1. The LOD and LOQ were found to be 0.055 and 0.168µg/ml. The % relative standard deviation were found less than 2. According to ICH guidelines the method has been validated for linearity, precision, accuracy, robustness, ruggedness, LOD and LOQ. The developed and validated method can be successfully applied for reliable quantification of Favipiravir in bulk form and pharmaceutical dosage form.

Starch-Grafted Polyacrylic Acid Copolymer with Acrylamide: An Advanced Adsorbent for Victoria Green B Dye Removal and Environmental Remediation

AbstractA new adsorbent, starch grafted polyacrylic acid copolymer with polyacrylamide (SG@AA-co-AM), was synthesized using free radical polymerization techniques. Proton nuclear magnetic resonance (1H NMR), Fourier-transform infrared spectrophotometry (FTIR), X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), particle size distribution (PSD), and fluorescent electron microscopy (FEM) were employed to elucidate the structure, crystalline nature, thermal stability, and surface morphology of SG@AA-co-AM. SG@AA-co-AM was utilized as an adsorbent for the removal of Victoria green B (VGB) dye from wastewater. SG@AA-co-AM exhibited a removal percentage (% R) of 97.6% towards VGB under optimized conditions: a contact time of 30 min, temperature of 25 °C, adsorbent dose of 20 mg, pH of 8, concentration of dye solution of 20 ppm, and volume of dye solution of 30 mL. The point of zero charge (PZC) for SG@AA-co-AM was determined to be 5.2. Nonlinear pseudo-second-order (PSO) and Langmuir adsorption isotherm models best fitted to the experimental data, with regression coefficients (R2) of 0.95 and 0.99, respectively. The results confirmed the chemi-sorption and monolayer adsorption of VGB onto SG@AA-co-AM. Thermodynamic studies revealed that the adsorption of VGB onto SG@AA-co-AM is endothermic and spontaneous. Furthermore, the regeneration experiment showed a decline of 3.9% after five cycles, confirming the economical and reusable nature of SG@AA-co-AM.

Experimental assessment of square-wave spatial spanwise forcing of a turbulent boundary layer

We present an experimental realisation of spatial spanwise forcing in a turbulent boundary layer flow, aimed at reducing the frictional drag. The forcing is achieved by a series of spanwise running belts, running in alternating spanwise direction, thereby generating a steady spatial square-wave forcing. Stereoscopic particle image velocimetry in the streamwise–wall-normal plane is used to investigate the impact of actuation on the flow in terms of turbulence statistics, drag performance characteristics, and spanwise velocity profiles, for a non-dimensional wavelength of λx+=397\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\lambda _x^+ = 397$$\\end{document}. In line with reported numerical studies, we confirm that a significant flow control effect can be realised with this type of forcing. The scalar fields of the higher-order turbulence statistics show a strong attenuation of stresses and production of turbulence kinetic energy over the first belt already, followed by a more gradual decrease to a steady-state energy response over the second belt. The streamwise velocity in the near-wall region is reduced, indicative of a drag-reduced flow state. The profiles of the higher-order turbulence statistics are attenuated up to a wall-normal height of y+≈100\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$y^+ \\approx 100$$\\end{document}, with a maximum streamwise stress reduction of 45% and a reduction of integral turbulence kinetic energy production of 39%, for a non-dimensional actuation amplitude of A+=12.7\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$A^+ = 12.7$$\\end{document}. An extension of the classical laminar Stokes layer theory is introduced, based on the linear superposition of Fourier modes, to describe the non-sinusoidal boundary condition that corresponds to the current case. The experimentally obtained spanwise velocity profiles show good agreement with this extended theoretical model. The drag reduction was estimated from a linear fit in the viscous sublayer in the range 2≤y+≤5\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$2 \\le y^+\\le 5$$\\end{document}. The results are found to be in good qualitative agreement with the numerical implementations of Viotti et al. (Phys Fluids 21, 2009), matching the drag reduction trend with A+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$A^+$$\\end{document}, and reaching a maximum of 20%.Graphical abstract

The association of maternal gestational weight gain with cardiometabolic risk factors in offspring: a systematic review and meta-analysis.

Gestational weight gain (GWG) is known to be a risk factor for offspring obesity, a precursor of cardiometabolic diseases. Accumulating studies have investigated the association of GWG with offspring cardiometabolic risk factors (CRFs), leading to inconsistent results. This study synthesized available data from cohort studies to examine the effects of GWG on offspring CRFs. Four electronic databases, including PubMed, Web of Science, Scopus, and Embase, were searched through May 2023. Cohort studies evaluating the association between GWG and CRFs (fat mass [FM], body fat percentage [BF%], waist circumference [WC], systolic blood pressure [SBP] and diastolic blood pressure, high-density-lipoprotein cholesterol [HDL-C] and low-density-lipoprotein cholesterol, triglyceride [TG], total cholesterol, fasting blood glucose, and fasting insulin levels) were included. Regression coefficients, means or mean differences with 95% confidence intervals [CIs], or standard deviations were extracted. Thirty-three cohort studies were included in the meta-analysis. Higher GWG (per increase of 1 kg) was associated with greater offspring FM (0.041 kg; 95% CI, 0.016 to 0.067), BF% (0.145%; 95% CI, 0.116 to 0.174), WC (0.154 cm; 95% CI, 0.036 to 0.272), SBP (0.040 mmHg; 95% CI, 0.010 to 0.070), and TG (0.004 mmol/L; 95% CI, 0.001 to 0.007), and with lower HDL-C (-0.002 mmol/L; 95% CI, -0.004 to 0.000). Consistently, excessive GWG was associated with higher offspring FM, BF%, WC, and insulin, and inadequate GWG was associated with lower BF%, low-density lipoprotein cholesterol, total cholesterol, and TG, compared with adequate GWG. Most associations went non-significant or attenuated with adjustment for offspring body mass index or FM. Higher maternal GWG is associated with increased offspring adiposity, SBP, TG, and insulin and decreased HDL-C in offspring, warranting a need to control GWG and to screen for cardiometabolic abnormalities of offspring born to mothers with excessive GWG. PROSPERO registration no. CRD42023412098.

Quantitative measurement of internal quality of carrots using hyperspectral imaging and multivariate analysis

The study aimed to measure the carotenoid (Car) and pH contents of carrots using hyperspectral imaging. A total of 300 images were collected using a hyperspectral imaging system, covering 472 wavebands from 400 to 1000 nm. Regions of interest (ROIs) were defined to extract average spectra from the hyperspectral images (HIS). We developed two models: least squares support vector machine (LS-SVM) and partial least squares regression (PLSR) to establish a quantitative analysis between the pigment amounts and spectra. The spectra and pigment contents were predicted and correlated using these models. The selection of EWs for modeling was done using the Successive Projections Algorithm (SPA), regression coefficients (RC) from PLSR models, and LS-SVM. The results demonstrated that hyperspectral imaging could effectively evaluate the internal attributes of carrot cortex and xylem. Moreover, these models accurately predicted the Car and pH contents of the carrot parts. This study provides a valuable approach for variable selection and modeling in hyperspectral imaging studies of carrots.

Geographic, Sociodemographic, and Clinical Factors Associated With Parental Self-Efficacy in Pediatric Patients With Hearing Loss.

To identify geographic, sociodemographic, and clinical factors associated with parental self-efficacy in a diverse cohort of deaf or hard-of-hearing (DHH) children. Cross-sectional study. Tertiary children's hospital. Four hundred forty parents of DHH children aged 0 to 17 completed the 25-item Scale of Parental Involvement and Self-Efficacy (SPISE) survey from 2014 to 2022. Residential addresses were geocoded and assigned Area Deprivation Index and Social Vulnerability Index rankings, and univariable and multivariable analyses were conducted using sociodemographic and clinical variables, including sex, race/ethnicity, insurance type, survey language, age at the survey, comorbidities, newborn hearing screening results, and hearing loss laterality and severity. Compared to English and Spanish-speaking parents, Chinese-speaking parents were associated with overall lower parental self-efficacy and involvement (regression coefficient = -0.518, [-0.929, -0.106]), Cohen's d = 0.606) and lower scores on items related to their ability to affect multiple aspects of their child's development and expression of thoughts as well as competency in checking and putting on their child's sensory device. Across univariable and multivariable analyses, besides Chinese language, all other sociodemographic, clinical, and geographic variables were not associated with SPISE score. To achieve the best patient outcomes, care teams can use the SPISE to evaluate parental self-efficacy and provide targeted support to parents at risk for having lower knowledge and confidence scores about critical skills necessary to facilitate their child's auditory access and language development. Notably, this study found similar reports of parental efficacy across various sociodemographic, clinical, and geographic variables but significantly lower SPISE scores in Chinese-speaking families.

Influence of moderate-to-high intensity physical activity on depression levels: a study based on a health survey of Chinese university students

ObjectiveThe study aims to examine how moderate-to-vigorous physical activity (MVPA) affects the severity of depression symptoms among Chinese college students. Additionally, it seeks to analyze the mediating mechanisms involving self-rated health and general self-efficacy.MethodsThe study utilized data from the 2023 Chinese College Health Tracking Survey and employed multiple linear regression and structural equation modeling techniques to investigate the impacts of MVPA on depression levels and its underlying mediating mechanisms among college students. The primary cohort comprised 49,717 enrolled college students from 106 universities in China.ResultsA total of 41,620 valid questionnaires were collected (response rate: 83.7%), with females accounting for 58.6%. In the past month, approximately 30.2% of college students engaged in MVPA. Self-rated health (B = − 0.282, P < 0.001) and general self-efficacy (B = − 0.133, P < 0.001) significantly influenced college students’ depression scores. Even after controlling for other variables, participating in MVPA remained significantly associated with reduced depression scores (B = − 0.062, P = 0.002). The results of the structural equation model showed that MVPA not only directly decreased college students’ depression scores but also indirectly reduced the likelihood of depression occurrence by improving their physical health status and general self-efficacy.ConclusionThe lack of physical activity among Chinese college students is evident. Engaging in MVPA can reduce the likelihood of depression among college students. MVPA achieves this reduction by enhancing college students’ general self-efficacy and improving their physical health. The factors influencing depression levels among college students are multifaceted. For future interventions targeting college students’ mental health, comprehensive approaches that incorporate behavioral and psychological factors should be emphasized.

Hydrodesulfurization of Dibenzothiophene: A Machine Learning Approach.

The hydrodesulfurization (HDS) process is widely used in the industry to eliminate sulfur compounds from fuels. However, removing dibenzothiophene (DBT) and its derivatives is a challenge. Here, the key aspects that affect the efficiency of catalysts in the HDS of DBT were investigated using machine learning (ML) algorithms. The conversion of DBT and selectivity was estimated by applying Lasso, Ridge, and Random Forest regression techniques. For the estimation of conversion of DBT, Random Forest and Lasso offer adequate predictions. At the same time, regularized regressions have similar outcomes, which are suitable for selectivity estimations. According to the regression coefficient, the structural parameters are essential predictors for selectivity, highlighting the pore size, and slab length. These properties can connect with aspects like the availability of active sites. The insights gained through ML techniques about the HDS catalysts agree with the interpretations of previous experimental reports.

Optimization of the QuEChERS Extraction of Mycotoxins in Maize Using Response Surface Methodology (RSM)

AbstractSeveral methods have been developed for the analysis and detection of mycotoxins in food; however, most do not make use of critical statistics and mathematical tools for precise optimization. This study developed, optimized, and validated a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction procedure for the extraction of multiple mycotoxins in maize and subsequent validation using liquid chromatography tandem mass spectrometry (LC–MS/MS). Central composite design (CCD) was used to optimize extraction conditions. Data analysis of full factorial screening experiments revealed that MeCN (%), FA (%), and extraction time significantly affected the mycotoxins recovery. Assessment of the statistical significance of the generated model using analysis of variance (ANOVA), coefficient tables, and surface plots showed the relative interactions of factors and the adequacy of the model. Thus, P values from the lack of fit (LOF) test ranged from 0.137– 0.467 and a composite desirability function of 0.91 was obtained. Using the optimum extraction conditions of 0.1% (v/v) FA in 80.2% MeCN for 74 min, 10 mycotoxins were effectively extracted with satisfactory recoveries (85–114%), coefficients of regression (R2 &gt; 0.98), coefficients of variation (CVs &lt; 15%), limit of quantifications (LOQs) (0.33–60.45 µg/kg), and other associated method validation parameters. The method validation was carried out according to Commission Implementing Regulation 2021/808 and Commission Regulation (EC) No 401/2006 of 23 February 2006. Application of this method to 20 maize samples collected from markets in Botswana showed detectable mycotoxins in 13 samples, with 2 exceeding the European Union (EU) maximum aflatoxin B1 (AFB1) limit, suggesting potential exposure to high levels of toxic mycotoxins in Botswana.

Association of cardiovascular risk factors and myocardial hypertrophy in women with preeclampsia history

AimsA historic of preeclampsia (PE) has been associated with cardiovascular disease (CVD) in women. There are substantial evidences that cardiovascular changes resulting from PE can persist even after pregnancy end. Therefore, the aims was to evaluate the prevalence of myocardial hypertrophy in young women 12 months after PE event as well as try to identify risk factors for these changes. Materials and methodsSingle-center observational prospective cross-sectional study that included 118 consecutive patients after 12 months of PE. Clinical and laboratory evaluations, echocardiogram were performed. Myocardial hypertrophy (LVH) was defined as an index myocardial mass ≥ 45 g/m2.7, for women. Classical risk factors for CVD were considered. Analysis included linear or logistic regression and Spearman's correlation coefficient. Significance level of 5 %. Key findingsSystemic arterial hypertension (SAH) was identified in 52 patients (44 %), overweight/obesity (OOB) in 82 (69 %), dyslipidemia in 68 (57 %) and metabolic syndrome in 47 patients (40 %). LVH was present in 35 cases (29 %) and associated with OOB (OR = 4.51; CI95%:1.18–17.17, p < 0.001), in a model corrected for age and SAH diagnosis. When only the metabolic syndrome components were analyzed, in the multiple logistic regression model, the abdominal circumference was the only clinical variable associated with LVH (OR = 17.65; CI95%:3.70–84.17; p < 0.001). SignificanceIt was observed a high prevalence of ventricular hypertrophy in young women with a history of pre-eclampsia. This condition was associated with the presence of obesity.

Research on Short Term Prediction of Electricity Demand in Hubei Province

The balance of electricity supply and demand is the basic condition for promoting the economic development of our country and improving the living standards of the people, and scientific forecasting of electricity demand is the premise of ensuring the balance of electricity supply and demand. Hubei Province is superior in geographical location, and its electricity demand and economic aggregate both rank high in the country, but due to the direct impact of the epidemic, its electricity demand has been affected. This paper uses OLS regression to obtain the linear regression equation of the three indicators of GDP and the proportion of the secondary industry structure before the epidemic from 2005 to 2018, and uses the Gray Forecast Model-assisted scenario analysis method to analyze the electricity consumption of Hubei Province under the influence of multiple factors, and predicts the electricity consumption of Hubei Province from 2019 to 2021 after removing the impact of the epidemic, and makes a short-term forecast of the electricity demand of the province from 2024 to 2029.

Elevation-related variations of soil disintegration and its driving forces in the water level fluctuation zone of the Three Gorges Reservoir, China

Soil disintegration is a key process of the early stages of soil erosion. The water level fluctuation zone (WLFZ) in reservoirs undergoes seasonal changes involving periodic alternations in inundation and exposure that can affect soil disintegration. In this study, we conducted experiments on pre-wetted undisturbed soil samples obtained from different elevations ranging from 155 to 180 m a.s.l. and different soil depths (0–10 and 10–20 cm) in the WLFZ of the Three Gorges Reservoir (TGR), upper Yangtze River, China. We investigated how soil disintegration varies depending on elevation within the WLFZ and used principal component analysis (PCA) and stepwise regression to identify the dominant variables affecting soil disintegration. Results show the following: (1) The disintegration ratio, which is a measure of the amount of soil disintegration that occurs during experiments, varied in the range of 0.45 %–4.79 % over 60 min, with 79 %–100 % of the disintegration occurring within the first 30 min. The disintegration ratio increases with decreasing elevation in the WLFZ. Soil samples from a depth of 0–10 cm disintegrated 0.43 % less on average than those from a depth of 10–20 cm. The relationship between disintegration rate and elevation can be expressed using an exponential function with R2 > 0.80. (2) The main variables loading onto the first three principal components (explain 91.4 % of the variation in all variables) identified by PCA were those involving soil aggregates, the plant root system, and soil particle-size, respectively. (3) Stepwise regression identified >0.25 mm water-stable aggregate content (Ws0.25) and root mean diameter (Droot) as the strongest predictors of soil disintegration and yielded a linear regression equation with R2 = 0.88. Ws0.25 and Droot were the most influential variables on the elevation-dependent occurrence/degree of disintegration. Such information is essential for understanding the occurrence and prevention of bank erosion in reservoir areas.