380 research outputs found

    Estimating a Treatment Effect with Repeated Measurements Accounting for Varying Effectiveness Duration

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    To assess treatment efficacy in clinical trials, certain clinical outcomes are repeatedly measured for same subject over time. They can be regarded as function of time. The difference in their mean functions between the treatment arms usually characterises a treatment effect. Due to the potential existence of subject-specific treatment effectiveness lag and saturation times, erosion of treatment effect in the difference may occur during the observation period of time. Instead of using ad hoc parametric or purely nonparametric time-varying coefficients in statistical modeling, we first propose to model the treatment effectiveness durations, which are the varying time intervals between the lag and saturation times. Then some mean response models are used to include such treatment effectiveness durations. Our methodologies are demonstrated by simulations and an application to the dataset of a landmark HIV/AIDS clinical trial of short-course nevirapine against mother-to-child HIV vertical transmission during labour and delivery

    Accelerated Hazards Model: Method, Theory and Applications

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    In an accelerated hazards model, the hazard functions of a failure time are related through the time scale-change, which is often a function of covariates and associated parameters. When the hazard functions have special properties, such as monotonicity in time, the parameters may be clinically meaningful in measuring a treatment effect. This paper reviews methodological and theoretical development of this model. Applications of the accelerated hazards model including sample size calculation in clinical trials, are also explored

    Machine Learning Based Probe Skew Correction for High-frequency BH Loop Measurements

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    Experimental characterization of magnetic components has grown to be increasingly important to understand and model their behaviours in high-frequency PWM converters. The BH loop measurement is the only available approach to separate the core loss as an electrical method, which, however, is susceptive to the probe phase skew. As an alternative to the regular de-skew approaches based on hardware, this work proposes a novel machine-learning-based method to identify and correct the probe skew, which builds on the newly discovered correlation between the skew and the shape/trajectory of the measured BH loop. A special technique is proposed to artificially generate skewed images from measured waveforms as augmented training sets. A machine learning pipeline is developed with the Convolutional Neural Network (CNN) to treat the problem as an image-based prediction task. The trained model has demonstrated a high accuracy and generalizability in identifying the skew value from a BH loop unseen by the model, which enables the compensation of the skew to yield the corrected core loss value and BH loop

    Integration and Industrialization of Film and Television Resources and its Significance for China’s Film and Television Work

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    The abundance of Film and Television resources in China is notable, yet the effective amalgamation and industrialization of these resources hold immense importance for the nation's film and television endeavors. Utilizing the full potential of policy, market, talent, and cultural assets, this research achieves the industrialization of Film and Television resources via a comprehensive amalgamation and integration of various capital, cooperation, and industry sectors. The findings of our study indicate that merging and mechanizing Film and Television resources in the realm of film and TV not only enhances their usage efficiency and financial worth, but also elevates their quality and expressive capacity. Consequently, this approach enables efficient education in Film and Television for the film and television sector in China. The research aids in comprehending the significance of incorporating Film and Television resource industrialization into film and TV projects, and also serves as a valuable methodological guide for diverse film and TV endeavors via these resources

    On the Socialist Core and Its Modern and Contemporary Values in How the Steel was Tempered from the Perspective of Education

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    In-depth study of literary appreciation and its educational value for the book "How the Steel was Tempered", interpreted from a pedagogical perspective and in the context of socialist core values. Firstly, starting from the socialist core, the deep relationship between characterization, plot setting and theme is analyzed. Secondly, through the analysis of the growth experience of the hero, Paul Kochagin, the educational significance of his socialist spirit such as adhering to ideals and faiths, unremitting self-improvement and optimism is revealed. Finally, the paper discusses the value of the work in the contemporary content, emphasizing its positive effects on cultivating contemporary youth to take social responsibility, promoting the socialist core values, and upgrading the national moral quality. The research shows that "How the Steel was Tempered", with its profound socialist core and extensive educational value, is of great practical significance for us to deepen the education of socialist core values and guide the youth to establish a correct worldview and values

    Analysis of the Prevalence and Influencing Factors of Chronic Obstructive Pulmonary Disease in Elderly Hospitalized Patients:a Study Based on a Comprehensive Geriatric Assessment System in Yunnan Province

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    BackgroundCurrent studies on chronic obstructive pulmonary disease (hereinafter referred to as COPD) mostly focus on the lung itself, while studies on the extrapulmonary manifestations of COPD are still lacking. Many studies in China and at abroad have shown that COPD is closely related to geriatric syndrome, but it has not been further confirmed.ObjectiveTo investigate the prevalence of COPD in senile inpatients in several hospitals in Yunnan Province in the past three years, and to explore the influencing factors of elderly COPD from the aspect of geriatric syndrome.MethodsA total of 2 182 newly admitted elderly patients (≥60 years old) in several hospitals of Yunnan Province from September 2018 to June 2021 were selected as the research objects and divided into COPD group and non-COPD group according to whether the patients had COPD. The software platform of "Comprehensive Geriatric Assessment System" independently developed by the Geriatrics Department of the First People's Hospital of Yunnan Province was used to collect general data from the patients. At the same time, the scales in the system were used to conduct a comprehensive geriatric evaluation of the patients, including the assessment of anxiety and depression by 15-item geriatric depression scale (GDS-15) , the assessment of insomnia situation by athens insomnia scale (AIS) , the assessment of family support by PAGAR scale, the assessment of fall risk by Morse fall scale, the assessment of cognitive function by mini-mental state examination (MMSE) , the assessment of nutrition status by mini nutritional assessment scale, the assessment of the patients' daily living ability by the basic activities of daily living (BADL) scale, the assessment of frailty state by the Fried Scale, the assessment of swallowing (choking) by swallowing function assessment scale, the assessment of urinary incontinence by incontinence questionnaire simple form (ICI-Q-SF) , the assessment of constipation by Roma Ⅲ scale, the assessment of pain by visual analogue scale (VAS) . The influencing factors of COPD in the elderly hospitalized patients were analyzed by binary Logistic regression.ResultsThere were 1 558 cases (71.4%) in the non-COPD group and 624 cases (28.6%) in the COPD group. The results of binary Logistic regression analysis showed that age ≥75 and <85 years, age≥85 years old, male, anxiety and depression, potential malnutrition, malnutrition, pre-frailty, frailty were independent influencing factors of COPD (P<0.05) .ConclusionElderly hospitalized patients aged ≥60 years have a higher prevalence of COPD and are closely associated with geriatric syndrome

    Correlation of Malnutrition,25-hydroxy Vitamin D and Interleukin-1β with Chronic Obstructive Pulmonary Disease in Elderly Inpatients

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    BackgroundThe specific pathogenesis of chronic obstructive pulmonary disease (COPD) is still not very clear so far, clinical interventions mainly focus on the control of pulmonary symptoms with drugs, however, the influence of extrapulmonary related factors of COPD has not caused enough attention.ObjectiveTo explore the correlation of malnutrition, 25-hydroxy vitamin D and interleukin-1β with COPD in elderly inpatients.MethodsA total of 305 inpatients (≥60 years old) were recruited from Department of Geriatrics, the First People's Hospital of Yunnan Province from November 2020 to August 2021, and divided into COPD group (n=89) and non-COPD group (n=216) according to the incidence of COPD. General information and comprehensive geriatric assessment results were compared between the two groups; binary Logistic regression analysis was used to analyze the influencing factors of COPD in elderly inpatients, and Spearman rank correlation analysis was used to analyze the correlation of malnutrition, 25-hydroxy vitamin D and interleukin-1β with COPD.ResultsThere were significant differences in age, gender, current smoking rate, nutritional status, cognitive function, incidence of anxiety and depression, incidence of disability, sleeping status, frailty status, proportion of multiple drugs, kinds of drugs used, platelet count, C-reactive protein, total protein, albumin, thyroxine, 25-hydroxy vitamin D, estradiol, testosterone, prothrombin time, D-dimer, interleukin-6 and interleukin-1β between the two groups (P<0.05) . The results of binary Logistic regression analysis showed that, current smoking〔OR=2.351, 95%CI (1.053, 5.249) 〕, underlying malnutrition〔OR=2.429, 95%CI (1.118, 5.276) 〕, malnutrition〔OR=3.936, 95%CI (1.355, 11.439) 〕, sleeplessness〔OR=2.584, 95%CI (1.094, 6.102) 〕, C-reactive protein〔OR=0.988, 95%CI (0.978, 0.999) 〕, 25-hydroxy vitamin D〔OR=0.929, 95%CI (0.880, 0.981) 〕and interleukin-1β〔OR=1.025, 95%CI (1.003, 1.047) 〕were independent influencing factors of COPD in elderly inpatients (P<0.05) . The results of Spearman rank correlation analysis showed that, malnutrition (rs=0.280, P<0.001) and interleukin-1β (rs=0.145, P=0.011) were positively correlated with the incidence of COPD in elderly inpatients, while 25-hydroxy vitamin D was negatively correlated with the incidence of COPD (rs=-0.264, P<0.001) .ConclusionMalnutrition, 25-hydroxy vitamin D and interleukin-1β are independent influencing factors of COPD in elderly inpatients. Among them, malnutrition and interleukin-1β are positively correlated with the incidence of COPD, while 25-hydroxy vitamin D is negatively correlated with the incidence of COPD

    Analysis on Flavor Quality of Brassica rapa L. from Different Varieties

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    Analysis the flavor quality of Brassica rapa L. from different varieties, in order to provide theoretical basis, which study on quality evaluation and improvement of flavor quality. The volatile flavor compounds were detected by gas chromatography-ion mobility spectrometry (GC-IMS). The content of 17 kinds of amino acids in Brassica rapa L. was determined by automatic amino acid analyzer, and Brassica rapa L. flavor was evaluated with sensory evaluation method. GC-IMS results showed that 68 volatile flavor components, including testers, alcohols, aldehydes and sulfur, were identified in SFB, RQH, KPZ, and KPB. There were some high aroma compounds such as (Z)-3-hexenol, dimethyl disulfide, 3-pentanone (D), acetone, propionaldehyde and 2-phenylethyl isothiocyanate. Through PCA and GC-IMS, it was good to distinguish among 4 different varieties of Brassica rapa L.. Results showed that the amino acids in 4 different varieties of Brassica rapa L. were all of various kinds, all containing 17 amino acids measured, including 7 essential amino acids for human body. The umami amino acids of SFB accounted for a relatively high proportion, and the sweet amino acids of KPZ accounted for a relatively high proportion. The highest comprehensive score of sensory evaluation was KPZ, followed by RQH. The flavor quality of Brassica rapa L. from different varieties were evaluated based on volatile flavor compounds, flavor amino acids and sensory evaluation, and the differences in flavor and quality among different Brassica rapa L. were clarified

    Incidence and timing of potentially high-risk arrhythmias detected through long term continuous ambulatory electrocardiographic monitoring

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    BACKGROUND: Ambulatory electrocardiographic (ECG) monitoring is the standard to screen for high-risk arrhythmias. We evaluated the clinical utility of a novel, leadless electrode, single-patient-use ECG monitor that stores up to 14 days of a continuous recording to measure the burden and timing of potentially high-risk arrhythmias. METHODS: We examined data from 122,815 long term continuous ambulatory monitors (iRhythm ZIO® Service, San Francisco) prescribed from 2011 to 2013 and categorized potentially high-risk arrhythmias into two types: (1) ventricular arrhythmias including non-sustained and sustained ventricular tachycardia and (2) bradyarrhythmias including sinus pauses >3 s, atrial fibrillation pauses >5 s, and high-grade heart block (Mobitz Type II or third-degree heart block). RESULTS: Of 122,815 ZIO® recordings, median wear time was 9.9 (IQR 6.8–13.8) days and median analyzable time was 9.1 (IQR 6.4–13.1) days. There were 22,443 (18.3 %) with at least one episode of non-sustained ventricular tachycardia (NSVT), 238 (0.2 %) with sustained VT, 1766 (1.4 %) with a sinus pause >3 s (SP), 520 (0.4 %) with a pause during atrial fibrillation >5 s (AFP), and 1486 (1.2 %) with high-grade heart block (HGHB). Median time to first arrhythmia was 74 h (IQR 26–149 h) for NSVT, 22 h (IQR 5–73 h) for sustained VT, 22 h (IQR 7–64 h) for SP, 31 h (IQR 11–82 h) for AFP, and 40 h (SD 10–118 h) for HGHB. CONCLUSIONS: A significant percentage of potentially high-risk arrhythmias are not identified within 48-h of ambulatory ECG monitoring. Longer-term continuous ambulatory ECG monitoring provides incremental detection of these potentially clinically relevant arrhythmic events
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