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Separations ◽  
2022 ◽  
Vol 9 (1) ◽  
pp. 12
Author(s):  
Renli Ma ◽  
John R. Dean

The former St. Antony’s Lead Works site, now the central part of an urban recreational park (Walker Riverside Park) in the east end of Newcastle upon Tyne (England, UK), has been assessed based on the Pb concentration in topsoil according to recently derived Category 4 Screening Level (C4SL) for public open space–park (POSpark, 1300 mg/kg). The site was divided into eight sampling areas following its physical layout. In total 79 soil samples were collected, characterised for acidity and organic matter content, and analysed by energy dispersive X-ray fluorescence (ED-XRF). The Pb levels in most of the samples, particularly those from the fringes of the site, are below the generic guideline value (down to 70 mg/kg). More than 16% of the samples from nearly all sampling areas, especially those sampling points around the former horizontal condenser flue and main chimney, contain levels of Pb significantly exceeding the limit (up to 206,000 mg/kg). No correlation is found between the Pb concentration in soil samples and their acidity (mostly neutral, pH 7.0 ± 0.5) or organic matter content (15.5 ± 4.1%). Using the Contaminated Land Exposure Assessment (CLEA) model (version 1.071), the site-specific risk assessment criteria (SSAC) for Lead (C4SL child), 2862 mg/kg, is obtained based on adjusted exposure frequency and occupancy period. Nearly 9% of the individual sample Pb concentrations (n = 79) across sample locations B, C, D and H are still above the specific value. Further statistical evaluation based on 95% upper confidence limit confirms that the site still represents a potential human health risk. This is because Pb concentrations, from two areas in the centre of the site (sample locations B and C), are greatly over the SSAC specific threshold (sample mean at location B is 12,350 mg/kg and at location C is 11,745 mg/kg).


Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 140
Author(s):  
Yanxia Yang ◽  
Pu Wang ◽  
Xuejin Gao

A radial basis function neural network (RBFNN), with a strong function approximation ability, was proven to be an effective tool for nonlinear process modeling. However, in many instances, the sample set is limited and the model evaluation error is fixed, which makes it very difficult to construct an optimal network structure to ensure the generalization ability of the established nonlinear process model. To solve this problem, a novel RBFNN with a high generation performance (RBFNN-GP), is proposed in this paper. The proposed RBFNN-GP consists of three contributions. First, a local generalization error bound, introducing the sample mean and variance, is developed to acquire a small error bound to reduce the range of error. Second, the self-organizing structure method, based on a generalization error bound and network sensitivity, is established to obtain a suitable number of neurons to improve the generalization ability. Third, the convergence of this proposed RBFNN-GP is proved theoretically in the case of structure fixation and structure adjustment. Finally, the performance of the proposed RBFNN-GP is compared with some popular algorithms, using two numerical simulations and a practical application. The comparison results verified the effectiveness of RBFNN-GP.


2021 ◽  
Vol 7 (1) ◽  
pp. p28
Author(s):  
Timothy T. Kuguyo ◽  
Edson Gandiwa

The study analysed the performance of trophy hunting tourism marketing mix activities in Zimbabwe in an attempt to improve tourism performance. Mixed methodology research comprising of 137 survey stakeholders and survey 274 tourists, one (1) focus group discussion and four (4) in-depth interview key informants was carried out from January 2019 to June 2019.Hunting quotas were based on the three regions, of Zimbabwe and Wildlife Management Authority, namely Southern Region, Western Region and Northern Region showing tourists type and stakeholder classes, and this was done. Quantitative data were analysed by correlation tests and one sample mean test values using the Statistical Package for Social Sciences (SPSS) software. Qualitative data were synthesised using content and narrative analyses. The study indicated that Zimbabwe performed highly in terms of process, product, people and place marketing mix strategies in its trophy hunting activities. The results indicated a weak relationship between perceptions of local and foreign trophy hunting tourists on rating the marketing mix performance of Zimbabwe. Tourists and stakeholders were found to have a significant positive relationship in their perceptions of wildlife tourism performance of Zimbabwe. The test of trophy hunting acceptability showed a statistically significant and above average performance of Zimbabwe on trophy hunting marketing mix. The study concluded that, though Zimbabwe performs high on overall trophy hunting tourism marketing mix strategies, there was need for improvements on promotion and pricing strategies.


2021 ◽  
Vol 10 (4) ◽  
pp. 69-78
Author(s):  
U. V. Nogaeva ◽  
Ju. M. Kotsur ◽  
E. V. Flisyuk ◽  
D. Yu. Ivkin ◽  
E. D. Semivelichenko ◽  
...  

Introduction. Osteoarthritis (OA) is the most common joint disease that affects more than 10 % of the world's population. More than 600 000 people are diagnosed for the first time each year, but these data do not reflect the true prevalence of the disease, since not all patients seek help from hospitals [1, 2].Aim. Pharmaceutical development of the composition and technology of a gel based on meloxicam, a purine derivative and an immunomodulating component for the treatment of OA with pharmacological substantiation of the content of active substances.Materials and methods. A combination of three active pharmaceutical substances was studied: a non-steroidal anti-inflammatory drug – meloxicam, a purine derivative and an original immunomodulator M. Sodium alginate, natrozole and xanthan gum were considered as gelling agents. Were identified two technological modes of obtaining a gel base. The concentrations of active substances were selected based on the results of preclinical studies. OA was modeled by the combined administration of 0.1 ml of a mixture of Freund's complete adjuvant with a 10 % talc suspension in isotonic sodium chloride solution in a ratio of 1 : 10 into the hock (tarsus) joint cavity. The criteria for choosing the optimal composition of the gel were the size of the damaged joint, exercise tolerance and the histological picture in comparison with intact and control animals. For quantitative data, sample mean values (M) and standard deviations (SD) were calculated. The results corresponded to the laws of normal distribution, statistical processing was carried out using one-way analysis of variance (One-Way ANOVA) using the GraphPad Prism 8.0.2 software, USA at the level of statistical significance of differences p < 0,05 и p < 0,001.Results and discussion. The composition was developed and the technology of the topical dosage form based on sodium alginate was proposed. Preclinical data indicate that the highest efficacy is achieved when using a formulation containing 3 % purine derivative, 5 % immunomodulator M and 0.5 % meloxicam. The developed composition for the effectiveness of suppressing the symptoms of OA showed results that exceeded the reference drug.Conclusion. An original combined agent for the treatment of OA has been developed. Due to the selected component composition, with greater efficiency, it was possible to reduce the dosage of meloxicam to 0.5 %, and the use of sodium alginate as a gelling agent contributed to the prolongation of the action of the gel and the subsequent reduction in the number of applications.


Author(s):  
Kitisak Kanjanun ◽  
Yan Bin ◽  
Yao Shuang'ao ◽  
Sakda Katawaethwarag

The General Regression Neural Network (GRNN) is one of the algorithms of artificial neural networks (ANN) that receives much attention in prediction applications. This research used the GRNN to predict the temperatureinduced deformation of unballasted track structures based on experimental data considering external weather conditions, such as sunshine duration, rain conditions, daily maximum temperature, daily minimum temperature, and daily average wind speed. The GRNN network predicts the average absolute error of the prediction results (0.0318 ℃), the maximum absolute error (1.7729 ℃), and the GRNN prediction sample mean squared error (0.070701). The average relative error is 0.32%. The finding of this study shows that the GRNN prediction method has good accuracy and robustness. Furthermore, it can promote the research of unballasted track temperature fields that are related to concrete structures.


Metabolites ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 871
Author(s):  
Lisa Maier ◽  
Ricarda von Krüchten ◽  
Roberto Lorbeer ◽  
Jule Filler ◽  
Johanna Nattenmüller ◽  
...  

Hepatic iron overload can cause severe organ damage; therefore, an early diagnosis and the identification of potential risk factors is crucial. We aimed to investigate the sex-specific distribution of hepatic iron content (HIC) in a population-based cohort and identify relevant associated factors from a panel of markers. We analyzed N = 353 participants from a cross-sectional sample (KORA FF4) who underwent whole-body magnetic resonance imaging. HIC was assessed by single-voxel spectroscopy with a high-speed T2-corrected multi-echo technique. A large panel of markers, including anthropometric, genetic, and laboratory values, as well as behavioral risk factors were assessed. Relevant factors associated with HIC were identified by variable selection based on LASSO regression with bootstrap resampling. HIC in the study sample (mean age at examination: 56.0 years, 58.4% men) was significantly lower in women (mean ± SD: 39.2 ± 4.1 s−1) than in men (41.8 ± 4.7 s−1, p < 0.001). Relevant factors associated with HIC were HbA1c as well as prediabetes for men and visceral adipose tissue as well as age for women. Hepatic fat, alcohol consumption, and genetic risk score for iron levels were associated with HIC in both sexes. In conclusion, there are sex-specific associations of HIC with markers of body composition, glucose metabolism, and alcohol consumption.


2021 ◽  
pp. 337-344
Author(s):  
Daniel-Andrei IORDAN ◽  
George-Dănuț MOCANU ◽  
Mircea-Dan MOCANU ◽  
Constantin MUNTEANU ◽  
Georgiana Bianca CONSTANTIN ◽  
...  

Background: Postural skills are fundamental in motor activities, so far no evidence of a direct relationship has been found, it is therefore recommended to consider the following directions, the higher the level of sports competition, the better the body posture; or better athletes also have a better body posture. Around the age of 11-14 years, it is a period of aggressive development, if the rapid growth of the bone system is not associated and symmetrical with the development of soft tissues serious postural deficiencies may develop in table tennis players. Methods: We used the web camera – photographic method (38) related to the Sensor Medica software that allows the acquisition of images in order to detect postural deficiencies and we considered it necessary to have a clear image of the level of technical-tactical training of female juniors III using 5 tests specific to topspin attack in order to assess the influence of body posture on such tests. Eighteen female juniors III (the mean ± SD age, height and weight were 11.1 ± 0.2 years, 147.7 ± 2.6 cm, 39.0 ± 2.0 kg). Descriptive statistical analysis was performed on the procedures for establishing the normality of data distribution, Levene's Test for Equality of Variances, the t test for independent samples. The confidence interval was set at 95% (p < 0.05), Results and Conclusions: Since Sig. (2-tailed) or p < α = 0.001 and taking into account that the confidence interval limits for the difference between the sample mean and the reference value (95% CI for the mean difference) do not contain the zero value, it is accepted that there are statistically significant differences between the shoulder inclination for the female athletes in the sample studied and the reference value. We identified that at the level of alignment between anatomical landmarks, the percentage of deficiency of the entire lot of female juniors III in the case of shoulders is 100% and at the level of PSIS is 66%, which validates several studies that stated that in this period of aggressive growth correlated with repetitive unilateral executions specific to the topspin attack lead to postural deficiencies. In terms of the influence of body posture on the quality level, we identified that Group 1 – (without PSIS imbalance) has a higher average overall efficiency of the 5 tests (11.33) compared to Group 2 (8.58), even if from a statistical point of view these differences are not significant. Keywords: Body posture, Asimmetry, Topspin attack, Table tennis, Sensor Medica,


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tae-Hwy Lee ◽  
He Wang ◽  
Zhou Xi ◽  
Ru Zhang

Abstract We consider a multiplicative decomposition of the financial returns to improve the density forecasts of financial returns. The multiplicative decomposition is based on the identity that financial return is the product of its absolute value and its sign. Advantages of modeling the two components are discussed. To reduce the effect of the estimation error due to the multiplicative decomposition in estimation of the density forecast model, we impose a moment constraint that the conditional mean forecast is set to match with the sample mean. Imposing such a moment constraint operates a shrinkage and tilts the density forecast of the decomposition model to produce the improved maximum entropy density forecast. An empirical application to forecasting density of the daily stock returns demonstrates the benefits of using the decomposition and imposing the moment constraint to obtain the improved density forecast. We evaluate the density forecast by comparing the logarithmic score (LS), the quantile score (QS), and the continuous ranked probability score (CRPS). We contribute to the literature on the density forecast and the decomposition models by showing that the density forecast of the decomposition model can be improved by imposing a sensible constraint in the maximum entropy framework.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 358-358
Author(s):  
Kristin Levoy ◽  
Eleanor Rivera ◽  
Molly McHugh ◽  
Alexandra Hanlon ◽  
Karen Hirschman ◽  
...  

Abstract As chronically ill adults age, increased fluctuations in health status result in frequent care transitions. Caregiver engagement is often a core component of evidence-based transitional care interventions, yet little is known about the relative contribution of this element to observed outcomes. This meta-analysis aimed to synthesize evidence of caregiver engagement in randomized control trials (RCT’s) of transitional care interventions, estimate the overall intervention effects on all-cause hospital readmissions, and test caregiver engagement as a moderator of interventions’ effects. Relative risk was the effect size, and the overall effect was estimated using inverse variance weighting. Fifty-four studies met criteria, representing 31,399 participants and 65 effect sizes. The weighted sample mean age was 64 years. The majority (64%) of interventions targeted participants with specific diagnoses, such as heart disease, but more than half (54%) lacked caregiver engagement components. Among all reviewed studies of transitional care interventions, the overall effect on all-cause readmissions at 1 month was non-significant (p=.123, k=28). However, intervention effects at 2 or more months were significant (RR=0.89, 95% CI: 0.82, 0.97, p=.007, k=26), indicating a 12% reduction in the relative risk of all-cause readmissions among intervention participants compared to controls. Caregiver engagement was found to moderate intervention effects (p=.05). Specifically, interventions that included caregiver engagement produced more robust effects (RR=0.83, 95% CI: 0.75, 0.92, p=.001), than those without such engagement (RR=0.97, 95% CI: 0.87, 1.08, p=.550). Findings suggest that transitional care interventions need to more explicitly engage caregivers as active partners in order to optimize patient outcomes.


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