coefficients of variation
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Diagnostics ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 163
Author(s):  
Gerd U. Auffarth ◽  
Tadas Naujokaitis ◽  
Louise Blöck ◽  
Anna Daghbashyan ◽  
Jan Meis ◽  
...  

The aim of this prospective clinical study was to establish and verify an adaptation for axial length (AL) measurement in silicone oil (SO)-filled pseudophakic eyes with a Scheimpflug and partial coherence interferometry (PCI)-based biometer. The AL was measured with a Pentacam AXL (OCULUS Optikgeräte GmbH, Wetzler, Germany) and IOLMaster 700 (Carl Zeiss Meditec, Jena, Germany). The coefficients of variation (CoV) and the mean systematic difference (95% confidence interval (CI)) between the devices were calculated. After implementing a setting for measuring AL in tamponaded eyes with a Pentacam based on data of 29 eyes, another 12 eyes were examined for verification. The mean AL obtained with the Pentacam was 25.53 ± 1.94 mm (range: 21.70 to 30.76 mm), and with IOLMaster, 24.73 ± 1.97 mm (ranged 20.84 to 29.92 mm), resulting in a mean offset of 0.80 ± 0.08 mm (95% CI: 0.77, 0.83 mm), p < 0.001. The AL values of both devices showed a strong linear correlation (r = 0.999). Verification data confirmed good agreement, with a statistically and clinically non-significant mean difference of 0.02 ± 0.04 (95% CI: −0.01, 0.05) mm, p = 0.134. We implemented a specific adaptation for obtaining reliable AL values in SO-filled eyes with the Pentacam AXL.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262278
Author(s):  
Qi Guo ◽  
Yuhan Sun ◽  
Jiangtao Zhang ◽  
Yun Li

To select elite Robinia pseudoacacia L. germplasm resources for production, 13 phenotypes and three physiological indicators of 214 seedlings from 20 provenances were systematically evaluated and analyzed. The leaf phenotypic and physiological coefficients of variation among the genotypes ranged from 3.741% to 19.599% and from 8.260% to 42.363%, respectively. The Kentucky provenance had the largest coefficient of variation (18.541%). The average differentiation coefficients between and within provenances were 34.161% and 38.756%, respectively. These close percentages showed that R. pseudoacacia presented high genetic variation among and within provenances, which can be useful for assisted migration and breeding programs. Furthermore, based on the results of correlations, principal component analysis and cluster analysis, breeding improvements targeting R. pseudoacacia’s ornamental value, food value, and stress resistance of were performed. Forty and 30 excellent individuals, accounting for 18.692% and 14.019%, respectively, of the total resources. They were ultimately screened, after comprehensively taking into considering leaf phenotypic traits including compound leaf length, leaflet number and leaflet area and physiological characteristics including proline and soluble protein contents. These selected individuals could provide a base material for improved variety conservation and selection.


Chemosensors ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Sarizhat D. Tataeva ◽  
Kurban E. Magomedov ◽  
Ruslan Z. Zeynalov ◽  
Naida D. Baygishieva ◽  
Viktorya S. Magomedova ◽  
...  

The technology for manufacturing a film membrane of the metamizole-selective electrode containing ion associate metamizole-octadecylammonium ODAH+MT− as an electrode active component (EAC) has been proposed. The main potentiometric characteristics of the metamizole-selective electrode have been determined. The expediency of the proposed design of the metamizole selective electrode for the determination of metamizole in dosage forms has been substantiated. The best composition of the membrane (wt.%) of the metamizole-selective electrode has corresponded to: ODAH+MT−—5.3; 2-nitrophenyloctylether—63.1; poly(vinyl chloride)—31.6. Electrode-active component in the membrane phase functions as an ion associate ODAH+MT−. Potentiometric characteristics of metamizole-selective electrode have been determined, which corresponded to: linear range 1 × 10−2–1 × 10−4 with limit of detection 4.58 × 10−5 M, electrode function slope −48.5 mV/dec., working interval pH 4.5–7.3, response time 60 s. The potentiometric coefficients of selectivity of the metamizole-selective electrode with respect to various ions have been determined. The possibility of determining metamizole in a medicinal product has been tested. The results of the analyses show good agreement between the two methods (relative error less than 7.0%) with coefficients of variation less than 5% for MT-SE and iodometric methods.


2021 ◽  
Vol 11 (1) ◽  
pp. 91
Author(s):  
Aurélie Truffot ◽  
Thomas Jouve ◽  
Johan Noble ◽  
Béatrice Bardy ◽  
Paolo Malvezzi ◽  
...  

The presence of anti-HLA antibodies is an increasing challenge in kidney transplantation. Tocilizumab (TCZ), a monoclonal antibody targeting the interleukin-6 receptor (IL-6R), has been proposed to complement conventional desensitization therapy. We aimed to describe TCZ plasma trough concentrations and their variability and to investigate the link between TCZ concentration and the evolution of anti-HLA antibodies. Sensitized kidney-transplant candidates treated monthly with TCZ (8 mg/kg) for desensitization were retrospectively included. TCZ concentrations were determined by liquid chromatography-tandem mass spectrometry. Seventy-four TCZ concentrations from 10 patients were analyzed. The TCZ trough concentration ranged from <1.0 to 52.5 mg·L−1, with a median of 25.6 mg·L−1 [25th–75th percentiles: 13.2–35.3 mg·L−1). The inter- and intra-individual coefficients of variation were 55.0% and 33.0%, respectively. The TCZ trough concentration was not related to IL-6 (rho = −0.46, p = 0.792), soluble IL-6R (rho = −0.81, p = 0.65) concentrations or reduction of anti-HLA antibodies (mixed-effects model adjusting, effect of TCZ trough concentration: rho = −0.004, p = 0.26). The individual median TCZ concentration tended to be associated with the number of antibodies, with an initial MFI > 3000 that dropped to <3000 after TCZ treatment (rho = 0.397, p = 0.083). TCZ trough concentrations in kidney-transplant candidates treated for desensitization were highly variable. Further studies on larger cohorts are needed to study the possible link between TCZ concentrations and the reduction of anti-HLA antibodies.


Author(s):  
L.S. Romanyuk

The aim of the research was to study the nature of variability of the main quantitative traits in hybrid populations of the second generation Phaseolus vulgaris L. within the framework of the task 13.00.01.28. F “To study the nature of the inheritance of quantitative traits in hybrids of create a starting material with improved flavoring properties.As a result of the studies carried out, it was found that regardless of the duration of the growing season of the parent components of the crossing, in the hybrid populations of the second generation, the limits of variability for this indicator went beyond the limits of the variability of the parent forms. The average values of the duration of the growing season in hybrids were intermediate between the indicators of the corresponding parent forms. The coefficients of variation in the parent forms were insignificant (1.1 – 1.4%); in hybrid populations they were low – from 4.9% (Line 744-14 / Ukrainka) to 9.2% (Line 741-14 / Suita).In terms of plant height, the limits of variability of hybrid offspring F2 went beyond the limits of variability of the parent components. The average values of the trait in hybrid populations significantly exceeded the corresponding indicators of the parent forms. The degree of variability in plant height of hybrid populations was significant in the combination Line 872-14 / Podolyanka-1 (the parent components differ in the type of plant growth) and was equal to 20.6% versus 3.5% and 4.9% for the corresponding parent forms. In other hybrid populations, the coefficient of variation was average (Ukrainka / Suita-16.5%; Line 741-14 / Suita – 13.5%; Line 744-14 / Ukrainka -10.1%) The degree of variability of the corresponding parental forms was in the range from 2.8% to 3.1%.The widest range of variability was observed according to the characteristics of the mass of seeds from the plant, the number of seeds from the plant, the number of beans from the plant. The degree of variability of the seed mass from the plant in hybrid populations ranged from 30.3% to 39.1% (in the parent forms from 9.1% to 21.7%); the number of seeds from the plant from 22.3% to 40.7% (in the parent forms from 9.8% to 20.1%); the number of beans from the plant from 28.1% to 38.3% (in the parent forms from 4.7% to 16.2%). The degree of variation of the studied traits in hybrid populations was 2–3 times higher than in the parent forms.By the weight of 100 seeds in the offspring of the second generation, the range of variation was much wider than this indicator in the parent forms. The degree of variability on this trait was average for hybrid populations (from 10.6% to 13.4%), and insignificant for parental forms (from 3.7% to 6.6%).It is possible that the most valuable in terms of breeding may be the hybrid combination Line 872-14/Podolyanka, from the widest range of variability in the studied traits in the second generation population.


Diagnostics ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2400
Author(s):  
Yu Jeong Choi ◽  
Juhye Roh ◽  
Sinyoung Kim ◽  
Kyung-A Lee ◽  
Younhee Park

Numerous immunoassays have been developed to measure the levels of chromogranin A (CgA), a useful biomarker for diagnosing and monitoring generally heterogeneous neuroendocrine tumors (NETs). Here, we evaluated the imprecision and linearity of three such assays: KRYPTOR (ThermoFisher Scientific), NEOLISA (EuroDiagnostica), and CgA-RIA (CisBio), using 123 samples for each assay. The correlation coefficients between the assays were 0.932 (CgA-RIA versus NEOLISA), 0.956 (KRYPTOR versus CgA-RIA), and 0.873 (NEOLISA versus KRYPTOR). KRYPTOR showed good precision, with percent coefficients of variation less than 5% for low and high concentration quality controls. Linearity was maintained over a wide concentration range. Comparison of CgA levels from three disease entities (NETs, non-NET pancreatic tumors, and prostate cancer) and healthy controls showed that patients with NETs had significantly higher CgA levels (n = 57, mean: 1.82 ± 0.43 log ng/mL) than healthy individuals (n = 20, mean: 1.51 ± 0.23 log ng/mL; p = 0.018). No other significant differences between groups were observed. All three immunoassays showed strong correlations in measured CgA levels. Because KRYPTOR operation uses a fully automated random-access system and requires shorter incubation times and smaller sample volumes, the KRYPTOR assay may improve laboratory workflow while maintaining satisfactory analytical performance.


2021 ◽  
Vol 6 (48) ◽  
pp. 21-21
Author(s):  
Vitaly Donskih ◽  
Tatiana Aniskina ◽  
Victоria Kryuchkova

The Tsumi apple tree is a valuable crop due to the presence of a gene for resistance to powdery mildew, abundant annual fruiting and a special decorative effect during flowering and fruiting. Its breeding potential has been little studied; therefore, it is necessary to study the morphometric characteristics of a flower and a fruit and establish connections between them. The collection of flowers and fruits of the Tsumi apple tree was carried out in the laboratory of cultivated plants of the Tsytsin Main Botanical Garden in 2021. The coefficients of variation and correlation according to Spearman were determined. It was found that the polymorphism of flower traits is at a very low level (from 4.4% to 14.2%). The number of flowers per inflorescence varies within 15.9%, which corresponds to the average level of polymorphism, as well as in the weight of the fruit (17.3%) and in the weight of seeds (19.5%). Variations in the length of the peduncle, the number of seeds, the length of the fruit, and the diameter of the fruit are at a very low level (6.9-13.6%). A significant number of reliable inverse (negative) correlations were found between signs of moderate strength (0.5 <r <0.6): a strong relationship between fruit weight and anther length (r = -0.73), fruit length and filament length (r = -0.71). A strong positive relationship was found between the following traits: fruit weight and fruit diameter (r = 0.79), seed weight. Keywords: POLYMORPHISM, FLOWER, CRABAPPLES, SORBOMALUS, MALUS ZUMI, TSUMI APPLE TREE, VARIABILITY, MORPHOLOGY


Author(s):  
Theerapong Kaewprasert ◽  
Sa-Aat Niwitpong ◽  
Suparat Niwitpong

Herein, we present four methods for constructing confidence intervals for the ratio of the coefficients of variation of inverse-gamma distributions using the percentile bootstrap, fiducial quantities, and Bayesian methods based on the Jeffreys and uniform priors. We compared their performances using coverage probabilities and expected lengths via simulation studies. The results show that the confidence intervals constructed with the Bayesian method based on the uniform prior and fiducial quantities performed better than those constructed with the Bayesian method based on the Jeffreys prior and the percentile bootstrap. Rainfall data from Thailand was used to illustrate the efficacies of the proposed methods.


2021 ◽  
Vol 14 (12) ◽  
pp. 1284
Author(s):  
Sofia Soares ◽  
Tiago Rosado ◽  
Mário Barroso ◽  
Eugenia Gallardo

The increase in the consumption of antidepressants is a public health problem worldwide, as these are a class of compounds widely used in the treatment of several illnesses, such as depression and anxiety. This work aimed to develop and optimize a method for the quantification of a number of antidepressants and their metabolites (fluoxetine, venlafaxine, O-desmethylvenlafaxine, citalopram, sertraline, and paroxetine) in 100 µL of oral fluid using the dried saliva spots (DSS) sampling approach and gas chromatography coupled with tandem mass spectrometry (GC–MS/MS). The method was validated, presenting linearity within the studied range, with detection and quantification limits ranging between 10 and 100 ng/mL, and coefficients of determination (R2) of at least 0.99 for all analytes. Recoveries were between approximately 13 and 46%. The analysis of precision and accuracy presented acceptable coefficients of variation and relative errors, considering the criteria usually accepted in the validation of bioanalytical procedures. The method herein described is the first to be reported using DSS for the extraction of antidepressants, proving to be a sensitive, simple, and fast alternative to conventional techniques, and capable of being routinely applied in clinical and forensic toxicology scenarios.


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