22 research outputs found

    Enhancing hourly heat demand prediction through artificial neural networks: a national level case study

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    Meeting the goal of zero emissions in the energy sector by 2050 requires accurate prediction of energy consumption, which is increasingly important. However, conventional bottom-up model-based heat demand forecasting methods are not suitable for large-scale, high-resolution, and fast forecasting due to their complexity and the difficulty in obtaining model parameters. This paper presents an artificial neural network (ANN) model to predict hourly heat demand on a national level, which replaces the traditional bottom-up model based on extensive building simulations and computation. The ANN model significantly reduces prediction time and complexity by reducing the number of model input types through feature selection, making the model more realistic by removing non-essential inputs. The improved model can be trained using fewer meteorological data types and insufficient data, while accurately forecasting the hourly heat demand throughout the year within an acceptable error range. The model provides a framework to obtain accurate heat demand predictions for large-scale areas, which can be used as a reference for stakeholders, especially policymakers, to make informed decisions

    Impact of within-visit systolic blood pressure change patterns on blood pressure classification : the Cardiovascular Risk in Young Finns Study

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    AIMS: Most international guidelines recommend that repeat blood pressure (BP) readings are required for BP classification. Two international guidelines diverge from this by recommending that no further BP measurements are required if the first clinic BP is below a hypertension threshold. The extent to which within-visit BP variability patterns change over time, and whether this could impact BP classification is unknown. We sought to examine this. METHODS AND RESULTS: Data were from the Cardiovascular Risk in Young Finns Study, a prospective cohort study. Up to 2799 participants were followed from childhood (9-15 years) to adulthood (18-49 years) over up to six visits. Patterns of within-visit systolic BP (SBP) variability were defined as no-change, decrease, increase between consecutive readings (with 5 mmHg change thresholds). Classification of SBP (normal, high-normal, hypertension) using the first reading was compared with repeat readings. On average, SBP decreased with subsequent measures, but with major individual variability (no-change: 56.9-62.7%; decrease: 24.1-31.6%; increase: 11.5-16.8%). Patterns of SBP variability were broadly similar from childhood to adulthood, with the highest prevalence of an increase among participants categorized with normal SBP (12.6-20.3%). The highest prevalence of SBP reclassification occurred among participants with hypertension (28.9-45.3% reclassified as normal or high-normal). The prevalence of reclassification increased with the magnitude of change between readings. CONCLUSION: There is a major individual variation of within-visit SBP change in childhood and adulthood and can influence BP classification. This highlights the importance of consistency among guidelines recommending that repeat BP measurements are needed for BP classification.publishedVersionPeer reviewe

    Within-visit SBP variability from childhood to adulthood and markers of cardiovascular end-organ damage in mid-life

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    Background: Within-visit SBP variability is associated with age and SBP, but its long-term clinical significance is unknown. We examined the association between child, adult, and life-time within-visit SBP variability with markers of end-organ damage using data from a 31-year longitudinal study.Methods: Within-visit SBP variability was calculated as the standard deviation of three sitting SBP readings among up to 3010 participants aged 6-18 years (childhood) who were re-measured up to seven times to mid-adulthood. Markers of cardiovascular end-organ damage in adulthood were carotid intima-media thickness, brachial flow-mediated dilatation, carotid distensibility, pulse wave velocity, left ventricular mass index, carotid plaque, and coronary artery calcification.Results: The mean (standard deviation) cumulative within-visit SBP variability was 2.7 (1.5) mmHg in childhood, 3.9 (1.9) mmHg in adulthood and 3.7 (1.5) mmHg across the observed life-time. Childhood within-visit SBP variability was not correlated with its subsequent values measured from 3 to 31 years later. With adjustment for age, sex, cumulative SBP, BMI and serum lipids, neither child, adult, or life-time cumulative within-visit SBP variability associated with markers of cardiovascular end-organ damage. However, higher child, adult, and life-time cumulative SBP significantly associated with higher carotid intima-media thickness, higher pulse wave velocity, lower brachial flow-mediated dilatation, lower carotid distensibility in adulthood.Conclusion: Within-visit SBP variability from childhood to adulthood does not provide additional predictive utility over SBP over the same period of the life course.</p

    Impact of within-visit systolic blood pressure change patterns on blood pressure classification: the Cardiovascular Risk in Young Finns Study

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    Aims Most international guidelines recommend that repeat blood pressure (BP) readings are required for BP classification. Two international guidelines diverge from this by recommending that no further BP measurements are required if the first clinic BP is below a hypertension threshold. The extent to which within-visit BP variability patterns change over time, and whether this could impact BP classification is unknown. We sought to examine this.Methods and results Data were from the Cardiovascular Risk in Young Finns Study, a prospective cohort study. Up to 2799 participants were followed from childhood (9-15 years) to adulthood (18-49 years) over up to six visits. Patterns of within-visit systolic BP (SBP) variability were defined as no-change, decrease, increase between consecutive readings (with 5 mmHg change thresholds). Classification of SBP (normal, high-normal, hypertension) using the first reading was compared with repeat readings. On average, SBP decreased with subsequent measures, but with major individual variability (no-change: 56.9-62.7%; decrease: 24.1-31.6%; increase: 11.5-16.8%). Patterns of SBP variability were broadly similar from childhood to adulthood, with the highest prevalence of an increase among participants categorized with normal SBP (12.6-20.3%). The highest prevalence of SBP reclassification occurred among participants with hypertension (28.9-45.3% reclassified as normal or high-normal). The prevalence of reclassification increased with the magnitude of change between readings.Conclusion There is a major individual variation of within-visit SBP change in childhood and adulthood and can influence BP classification. This highlights the importance of consistency among guidelines recommending that repeat BP measurements are needed for BP classification.</p

    Bi-Directionality between Physical Activity within School and Fundamental Movement Skills in School-Aged Students: A Cross-Lagged Study

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    Background: Evidence has indicated the health importance of fundamental movement skills (FMS) and physical activity (PA) in children and their relationships seems bidirectional. However, their bidirectional relationship has not yet been fully answered in the literature. Aim: This study sought to determine bidirectional relationship between FMS and PA in children using cross-lagged study design. Methods: A total of 183 second-level students (8.8 &plusmn; 1.1 years old) from three primary schools in Henan Province, China were selected as subjects. The average number of steps per school day was used as the amount of PA in the school environment; the third edition of the test of gross motor development was used for FMS testing. The baseline data (T1) and tracking data (T2) were collected at the beginning and end of the fall semester, respectively. The two tests were separated by 3 months (11 weeks), and a cross-lag model analysis was performed. Based on the hypothetical model, we tested the cross-lag effect of children&rsquo;s PA and FMS. Results: The model fit index was &chi;2/df = 2.861 (p &lt; 0.001, n = 183); goodness of fit index GFI = 0.900; NFI = 0.909; CFI = 0.931 and the 95%CI was between 0.071&ndash;0.192. The RMSEA = 0.063, and the standardized residual root mean square SRMR = 0.029. The T1 FMS can be used to predict the number of steps in the T2 teaching days with statistical significance (&beta; = 0.22, 95% CI: 0.07&ndash;0.38, p = 0.003). However, the T1 steps cannot be used to predict the T2 FMS (&beta; = 0.05, 95% CI: 0.07&ndash;0.13, p = 0.475). Further analysis shows that the main contributor to these relationships are ball skills in the FMS. Conclusions: The relationship between children&rsquo;s fundamental movement skills and PA is not two-way. Students with higher FMS are expected to reach higher levels of PA after undergoing school PA in a teaching cycle. The PA of the students can be improved by improving their motor skills, which further improves their physical and mental health

    Side Null Analysis of the Main-Auxiliary Antenna Array for Noncooperative Interference Cancellation

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    In interference cancellation, the null at the angle of arrival (AoA) of interference can suppress interference. However, due to the large spacing between array elements and the periodicity of the array, some small nulls at the angles of noninterference are formed inevitably. When the AoA of the desired signal is in these small nulls, they impair the effectiveness of interference cancellation by attenuating the desired signal. This paper proposes the concept of a side null to represent these nulls in the noninterference direction. And the cancellation ratio of the desired signal (SCR) is deduced to quantitatively characterize the side null. The spatial noncooperative interference cancellation model based on the main-auxiliary antenna array is established. Based on this, the SCR is derived to evaluate the amount of desired signal attenuation. Then the simulation, respectively, in two-dimensional plane and three-dimensional space, describes the side null visually. Moreover, the method of side null reduction is discussed by modulation of the array. Finally, the existence of side null and its influence on interference cancellation are verified through the experiments. The results of the simulation and experiment are in good agreement, and both support the theoretical analysis

    Modeling and analysis for group delay mismatch effect on wideband adaptive spatial interference cancellation

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    Abstract The adaptive interference cancellation technique has been widely utilized in radar, GPS, data link, etc., systems to address challenges from external interference, such as co-site and hostile interference. Since the anti-jamming performance of the adaptive interference cancellation technique is sensitive to group delay mismatch between channels, the group delay mismatch becomes one of the main factors that limit the system’s anti-jamming capability. However, the traditional adaptive interference cancellation system’s mathematical model cannot quantitatively characterize the group delay mismatch effect on the wideband interference cancellation performance. In this paper, the mathematical model of the wideband adaptive spatial interference cancellation (ASIC) system is established, which considers the group delay mismatch, to quantitatively analyze the impact of group delay mismatch on the hostile interference cancellation. The mathematical model utilizes the weighted multi-tone signals to fit the wideband interference, and then, delay differences are attached to each tone signal to simulate the group delay mismatch. Then, the analytic expressions of weight and interference cancellation ratio are derived, which consider the interference bandwidth and group delay mismatch, to quantitatively analyze the group delay mismatch effect on the anti-jamming performance of the wideband ASIC system. Simulation results indicate that the theoretical analysis based on the mathematical model of wideband ASIC system are accurate, which can achieve the quantitative analysis of the group delay mismatch effect on the WIC performance

    Increased expression of Gp96 by HBx-induced NF-κB activation feedback enhances hepatitis B virus production.

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    Elevated expression of heat shock protein gp96 in hepatitis B virus (HBV)-infected patients is positively correlated with the progress of HBV-induced diseases, but little is known regarding the molecular mechanism of virus-induced gp96 expression and its impact on HBV infection. In this study, up-regulation of gp96 by HBV replication was confirmed both in vitro and in vivo. Among HBV components, HBV x protein (HBx) was found to increase gp96 promoter activity and enhance gp96 expression by using a luciferase reporter system, and western blot analysis. Further, we found that HBx-mediated regulation of gp96 expression requires a NF-κB cis-regulatory element on the gp96 promoter, and chromatin immunoprecipitation results demonstrated that HBx promotes the binding of NF-κB to the gp96 promoter. Significantly, both gain- and loss-of-function studies showed that gp96 enhances HBV production in HBV-transfected cells and a mouse model based on hydrodynamic transfection. Moreover, up-regulated gp96 expression was observed in HBV-infected patients, and gp96 levels were correlated with serum viral loads. Thus, our work demonstrates a positive feedback regulatory pathway involving gp96 and HBV, which may contribute to persistent HBV infection. Our data also indicate that modulation of gp96 function may represent a novel strategy for the intervention of HBV infection

    Effect of Mobile Phone Addiction on Physical Exercise in University Students: Moderating Effect of Peer Relationships

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    Objective: The influence of mobile phone addiction (MPA) on physical exercise in university students was explored, and peer relationships were introduced as a moderating variable. Methods: A cross-sectional study design was adopted, and an online survey questionnaire was conducted to investigate two universities in Nantong City, Jiangsu Province, and Chongzuo City, Guangxi Zhuang Autonomous Region. A total of 4959 university students completed the questionnaire. Measurement tools included the Mobile Phone Addiction Tendency Scale, the Physical Activity Rating Scale, and the Peer Rating Scale of university students. Results: University students scored 39.322 &plusmn; 15.139 for MPA and 44.022 &plusmn; 7.735 for peer relationships, with 87.8% of their physical exercise, in terms of exercise grade, being classified as medium or low intensity. The MPA of the university students was negatively correlated with peer relationships (r = &minus;0.377, p &lt; 0.001) and physical exercise behavior (r = &minus;0.279, p &lt; 0.001). The moderating effect of peer relationships on the MPA-physical exercise behavior relationship was significant (&Delta;R2 = 0.03, p &lt; 0.001). Conclusions: The physical exercise of university students was at a medium or low intensity. The more serious the university students&rsquo; addiction to mobile phones was, the lower the amount of physical exercise. The physical activity of males was higher than that of females. MPA and peer relationships were the limiting factors of the physical exercise behavior of university students. Under the lower effect of peer relationship regulation, MPA had a greater negative impact on physical exercise behavior. The data from this research can provide theoretical support to improve the participation of university students in physical activities

    Reaction Behaviors and Mechanism of Isobutane/Propene Alkylation Catalyzed by Composite Ionic Liquid

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    Alkylation performance of isobutane with propene catalyzed by composite ionic liquid (CIL) was deeply investigated. Critical components of alkylate were C7 isoparaffins, which Alkylation mainly 2,3-dimethylpentane and 2,4-dimethylpentane. The optimal reaction conditions were as follows: reaction temperature of 15 degrees C, reaction time of 5 s, stirring rate of 1500 rpm, IL/HC ratio of 1.0, and I/O ratio of 68. Under these conditions, the yield of C7 isoparaffins was 78.9 wt %, and the research octane number of alkylate was 86.2. The reaction mechanism and pathway of isobutane/propene alkylation were proposed on the basis of component distribution. C7 isoparaffins were mainly from direct alkylation, and C8 isoparaffins were mainly from disproportionation. Compared with traditional concentrated sulfuric acid and hydrofluoric acid catalysts, more direct alkylation and less self-alkylation occurred, and the yield of propane was much lower when CIL was used. It was also proved that propene could be used in the CIL-catalyzed alkylation industrial unit due to the low propane production
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