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2021 ◽  
Author(s):  
Pasquale Alessio Sauchelli ◽  
Greta Botti ◽  
Marco Gesi ◽  
Miriam Rosa

Background and rationale Professional sport physiotherapist profile is characterised by eleven specific competences, defined by standards which are described by the Sports Physiotherapy for All (SPA) project [1]. Among these, performance evaluation and enhancement are fundamental in order to let athletes achieve their specific sport gestures best execution with a relevant impact on functional outcome. They alsoinfluencepositively on the decrease of injury risk [2-4]. Based on this cultural background, it is necessary that professionals evaluate their own clinicalpractice in order to match international standards, increase their work quality satisfying the functional requests of the sport environment, matching the perspective changes driven by the scientific community [2]. Study aim This survey aims to: •assess how Italian sport physiotherapists perform education and enhancement of the athlete performance in their clinical practice. •evaluate confidence of Italian professionals in performing such competence while managing the athlete performance. The average competencies of the analysed sample will be quantified and compared with what is set by the current scientific evidences regarding performance enhancement in athletes. Study design This observational cross-sectional study will be conducted in Italy through a digital questionnaire administration to a sample of 1093 sport physiotherapists [5]. Considering around 65000 Italian physiotherapists as a reference population, a confidence interval of 95% and a relative standard error of 3%, the necessary sample in order to have relevant results for the whole selected population is 1093 professionals [6-7]. This sample composed of Italian professionals will be recruited through social channels and/or newsletters sent by e-mail. The questionnaire will be filled in only after privacy law requirements acceptance and meeting inclusion criteria by the recruited sample. Results from this survey will be reported according to criteria set by STROBE guidelines and will be quantified and interpreted following the above-mentioned study aim. This study will be performed in accordance with the Checklist for Reporting Results of Internet E-survey criteria (CHERRIES) and with ethical principles contained in the Helsinki Declaration [8-10]. Committee on Bioethics of University of Pisa approved the present study.


2021 ◽  
Author(s):  
Hanna Piwowarska-Bilska ◽  
Sara Kurkowska ◽  
Bozena Birkenfeld

Abstract Background99mTc-HYNIC-TOC (Tektrotyd) is a radiopharmaceutical used for the diagnosis of lesions with overexpression of somatostatin receptors. The purpose of this study was to optimise the method and estimate normal ranges for standardized uptake values of Tektrotyd in healthy livers. MethodsAn analysis of SUVs normal ranges was performed for images acquired in a selected “healthy group” of 42 patients evaluated for NET tumours. The “pathological group” comprised 20 patients with liver lesions detected by scintigraphic imaging. Normal ranges for radiopharmaceutical uptake values were estimated based on the quantitative analysis of images acquired with a GE Healthcare NM/CT 850 gamma camera.ResultsThe method for healthy liver segmentation in SPECT/CT was optimized. The normal range of SUVs for the liver was: SUVbw max [5.2-14.0] g/ml and SUVlbm max [3.5-9.5] g/ml. The relative standard error (relative SE) of activity concentration estimated in the phantom study for the largest hot spheres was: ϕ=37mm- 5.9%, ϕ=28mm- 7.1%, ϕ=22mm- 11.4%, and ϕ=17mm- 22%.Conclusions· Segmentation in the mid-coronal CT image, at one-fourth of the height of the liver measured from the top, with a medium-sized VOI outlined on a given transverse SPECT slice was regarded as the optimal method for estimating normal ranges for standardized uptake values.· It is necessary to standardise quantification methods in the SPECT/CT studies. Our work is a step forward in obtaining standardisation of SPECT/CT SUV calculation methods.· Calculations for radiopharmaceutical uptake in tumours with volumes smaller than 5 ml are biased with a significant measurement error.


2021 ◽  
pp. 096703352110187
Author(s):  
Dong Sun ◽  
Jordi Cruz ◽  
Manel Alcalà ◽  
Roser Romero del Castillo ◽  
Silvia Sans ◽  
...  

Fast and massive characterization of quality attributes in tomatoes is a necessary step toward its improvement; for sensory attributes this process is time-consuming and very expensive, which causes its absence in routine phenotpying. We aimed to assess the feasibility of near infrared (NIR) spectroscopy as a fast and economical tool to predict both the chemical and sensory properties of tomatoes. We built partial least squares models from spectra recorded from tomato puree and juice in 53 genetically diverse varieties grown in two environments. Samples were divided in calibration (210 samples for chemical traits, 45 samples for sensory traits) and validation sets (60 and 10, respectively) using the Kennard Stone algorithm. Models from puree spectra gave validation r2 values higher than 0.97 for fructose, glucose, soluble solids content, and dry matter (relative standard error of prediction, RSEP% ranged 3.5–5.8), while r2 values for sensory properties were lower (ranging 0.702–0.917 for taste-related traits (RSEP%: 9.1–20.0), and 0.009–0.849 for texture related traits (RSEP%: 3.6–72.1)). For sensory traits such as explosiveness, juiciness, sweetness, acidity, taste intensity, aroma intensity, and mealiness, NIR spectroscopy is potentially useful for scanning large collections of samples to identify likely candidates to select for tomato quality.


2021 ◽  
Vol 12 ◽  
Author(s):  
Min Zhu ◽  
Mei-xia Wang ◽  
Zi-ran Li ◽  
Wei Wang ◽  
Xia Su ◽  
...  

Objective: To develop a population pharmacokinetic (PK) model for ropeginterferon alfa-2b and to compare its PK properties between Caucasian and Chinese populations.Methods: A population PK model was developed based on data from two phase I clinical trials conducted in Caucasian and Chinese individuals, to evaluate the influence of ethnicity on the PKs of ropeginterferon alfa-2b.Results: We included 456 observations from 30 healthy Caucasian subjects and 438 observations from 27 healthy Chinese subjects in the population PK analysis. The PKs of ropeginterferon alfa-2b were best described by a one-compartment quasi-equilibrium approximated target-mediated drug disposition model with first-order absorption and absorption lag times. The typical value (relative standard error%) of apparent clearance (CL/F) and volume of distribution of ropeginterferon alfa-2b in 70-kg subjects were 0.778 (12%) L/day and 2.32 (14%) L, respectively. Body weight was the only significant factor affecting the CL/F. There were no obvious differences in the PK properties of ropeginterferon alfa-2b, and predicted steady-state exposure was similar in the Chinese and Caucasian populations.Conclusion: No significant ethnic differences in ropeginterferon alfa-2b PKs were observed between the Chinese and Caucasian populations.


2021 ◽  
Author(s):  
Jennifer L Brazeal ◽  
Benjamin N Sacks

Non-invasive genetic sampling and spatially explicit capture-recapture (SCR) models are used increasingly to estimate abundance of wildlife populations, but have not been adequately tested on gregarious animals such as elk (Cervus canadensis), for which correlated space use and movements violate model assumptions of independence. To evaluate the robustness and accuracy of SCR, and to assess the utility of an alternative non-invasive method for estimating density of gregarious ungulates, we utilized a tule elk (Cervus canadensis nannodes) population of known size within a fenced enclosure on the San Luis National Wildlife Refuge in central California. We evaluated fecal genetic SCR to camera trap-based random encounter model (REM) approaches to density estimation based on comparison to the true abundance. We also subsampled the dataset to explore the effects of varying search effort and elk density on the precision and accuracy of results. We found that SCR outperformed REM methods in the full datasets, and reliably provided accurate (relative bias <10%) and reasonably precise (relative standard error ≤20%) estimates of density at moderately low to high densities (6-17 elk/km2), when the subsampling scenarios yielded a minimum average of 20 recaptures. We also found that the number of samples used to construct detection histories was a reliable predictor of precision, and could be used to establish minimum sampling requirements in future population surveys of elk. Although field-testing in free-ranging populations is needed, our results suggest that non-invasive genetic SCR is a promising tool for future population studies and monitoring of elk and potentially other gregarious ungulates. In contrast, the REM estimate of density was highly inaccurate, imprecise, and highly sensitive to camera parameters.


Author(s):  
Abdel Hameed I M Ebid ◽  
Sara M Abdel Motaleb ◽  
Mahmoud I Mostafa ◽  
Mahmoud M A Soliman

Objective: This study aimed to characterize a validated model for predicting oocyte retrieval in controlled ovarian stimulation (COS) and to construct model-based nomograms for assistance in clinical decision-making regarding the gonadotropin protocol and dose.Methods: This observational, retrospective, cohort study included 636 women with primary unexplained infertility and a normal menstrual cycle who were attempting assisted reproductive therapy for the first time. The enrolled women were split into an index group (n=497) for model building and a validation group (n=139). The primary outcome was absolute oocyte count. The dose-response relationship was tested using modified Poisson, negative binomial, hybrid Poisson-Emax, and linear models. The validation group was similarly analyzed, and its results were compared to that of the index group. Results: The Poisson model with the log-link function demonstrated superior predictive performance and precision (Akaike information criterion, 2,704; λ=8.27; relative standard error (λ)=2.02%). The covariate analysis included women’s age (p<0.001), antral follicle count (p<0.001), basal follicle-stimulating hormone level (p<0.001), gonadotropin dose (p=0.042), and protocol type (p=0.002 and p<0.001 for short and antagonist protocols, respectively). The estimates from 500 bootstrap samples were close to those of the original model. The validation group (n=139) showed model assessment metrics comparable to the index model. Based on the fitted model, a static nomogram was built to improve visualization. In addition, a dynamic electronic tool was created for convenience of use.Conclusion: Based on our validated model, nomograms were constructed to help clinicians individualize the stimulation protocol and gonadotropin doses in COS cycles.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Vito Di Bona

Abstract The Fetal–Infant mortality rate (FIMR) is the basic surveillance statistic in perinatal periods of risk (PPOR) analyses. This paper presents a model for the FIMR as the ratio of two Poisson random variables. From this model, expressions for estimators of variance, standard error, and relative standard error are developed. The coverage properties of interval estimators for the FIMR are investigated in a simulation study for both small and large populations and FIMR rates. Results from these studies are applied to a PPOR analysis of NC vital records. Results suggest that the sample size guidance provided in the literature to ensure statistical reliability is overly conservative and interval construction methodology should be selected based on population size.


Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2473
Author(s):  
Liang Zhao ◽  
Chun Liang Liu

The thickness effect of solid dielectrics means the relation between the electric breakdown strength (EBD) and the dielectric thickness (d). By reviewing different types of expressions of EBD on d, it is found that the minus power relation (EBD = E1d−a) is supported by plenty of experimental results. The physical mechanism responsible for the minus power relation of the thickness effect is reviewed and improved. In addition, it is found that the physical meaning of the power exponent a is approximately the relative standard error of the EBD distributions in perspective of the Weibull distribution. In the end, the factors influencing the power exponent a are discussed.


2020 ◽  
Vol 13 (11) ◽  
pp. 5873-5890
Author(s):  
Melodie Lao ◽  
Leigh R. Crilley ◽  
Leyla Salehpoor ◽  
Teles C. Furlani ◽  
Ilann Bourgeois ◽  
...  

Abstract. Atmospheric HONO mixing ratios in indoor and outdoor environments span a range of less than a few parts per trillion by volume (pptv) up to tens of parts per billion by volume (ppbv) in combustion plumes. Previous HONO calibration sources have utilized proton transfer acid displacement from nitrite salts or solutions, with output that ranges from tens to thousands of ppbv. Instrument calibrations have thus required large dilution flows to obtain atmospherically relevant mixing ratios. Here we present a simple universal source to reach very low HONO calibration mixing ratios using a nitrite-coated reaction device with the addition of humid air and/or HCl from a permeation device. The calibration source developed in this work can generate HONO across the atmospherically relevant range and has high purity (> 90 %), reproducibility, and tunability. Mixing ratios at the tens of pptv level are easily reached with reasonable dilution flows. The calibration source can be assembled to start producing stable HONO mixing ratios (relative standard error, RSE ≤ 2 %) within 2 h, with output concentrations varying ≤ 25 % following simulated transport or complete disassembly of the instrument and with ≤ 10 % under ideal conditions. The simplicity of this source makes it highly versatile for field and lab experiments. The platform facilitates a new level of accuracy in established instrumentation, as well as intercomparison studies to identify systematic HONO measurement bias and interferences.


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