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2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Johannes Müller ◽  
Walter Plöchl ◽  
Paul Mühlbacher ◽  
Alexandra Graf ◽  
Anne-Margarethe Kramer ◽  
...  

AbstractA high number of trauma patients are under the influence of alcohol. Since many of them need immediate surgical procedures, it is imperative to be aware of the interaction of alcohol with general anesthesia. To counter challenges that arise from clinical studies, we designed an animal experiment in which 48 adult Wistar rats either received 1 g · kg−1 ethanol, 2 g · kg−1 ethanol or placebo via intraperitoneal application. Subsequently, they were anesthetized with an individual concentration of sevoflurane. The minimum alveolar concentration (MAC) of the different groups was assessed using Dixon’s up-and-down design and isotonic regression methods. The bootstrap estimate of the MAC of sevoflurane in the placebo group was 2.24 vol% (95% CI 1.97–2.94 vol%). In the low dose ethanol group, the bootstrap estimate was 1.65 vol% (95% CI 1.40–1.98 vol%), and in the high dose ethanol group, it was 1.08 vol% (95% CI 0.73–1.42 vol%). We therefore report that intraperitoneal application of 1 g · kg−1 or 2 g · kg−1 ethanol both resulted in a significant reduction of the MAC of sevoflurane in adult Wistar rats: by 26.3% and 51.8% respectively as compared to placebo.


2021 ◽  
Vol 9 (2) ◽  
pp. 381
Author(s):  
Robert Starke ◽  
Maysa Lima Parente Fernandes ◽  
Daniel Kumazawa Morais ◽  
Iñaki Odriozola ◽  
Petr Baldrian ◽  
...  

Revealing the relationship between taxonomy and function in microbiomes is critical to discover their contribution to ecosystem functioning. However, while the relationship between taxonomic and functional diversity in bacteria and fungi is known, this is not the case for archaea. Here, we used a meta-analysis of 417 completely annotated extant and taxonomically unique archaeal genomes to predict the extent of microbiome functionality on Earth contained within archaeal genomes using accumulation curves of all known level 3 functions of KEGG Orthology. We found that intergenome redundancy as functions present in multiple genomes was inversely related to intragenome redundancy as multiple copies of a gene in one genome, implying the tradeoff between additional copies of functionally important genes or a higher number of different genes. A logarithmic model described the relationship between functional diversity and species richness better than both the unsaturated and the saturated model, which suggests a limited total number of archaeal functions in contrast to the sheer unlimited potential of bacteria and fungi. Using the global archaeal species richness estimate of 13,159, the logarithmic model predicted 4164.1 ± 2.9 KEGG level 3 functions. The non-parametric bootstrap estimate yielded a lower bound of 2994 ± 57 KEGG level 3 functions. Our approach not only highlighted similarities in functional redundancy but also the difference in functional potential of archaea compared to other domains of life.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
Felipe Vieira Guimarães ◽  
Tiago Medeiros de Souza ◽  
Richard Rangel Rodrigues ◽  
Rosana Souza-Lima

Abstract The large number of less-known coastal drainages in the Atlantic Forest still represents an important gap in the knowledge of ichthyofauna. It is evaluated the taxonomic diversity, frequency and constancy of occurrence, and the distribution of species in the various segments of the Perequê-Açu river basin, state of Rio de Janeiro, Brazil. Twelve sampling campaigns resulted in 13,423 individuals, belonging to seven orders, 10 families, 21 genera, and 23 native species. Cyprinodontiformes and Siluriformes represented about 87.2% of the total abundance, mainly due to the contribution of Phalloceros anisophallos and Schizolecis guntheri, which account for 63.2% of the total sampled individuals. The analysis of constancy of occurrence reveals that 78.3% of the drainage species are residents, with approximately 93% of the residents of the Carrasquinho River sub-basin. The Sertões River sub-basin had the largest number of species in total: 18. The rarefaction curve did not reach an asymptote, although Chao 2 and bootstrap estimate the richness of 23.9 species and 23.7 species, respectively. The results of PERMANOVA, PCoA, and SIMPER indicate that the fish composition along the catchment is not homogeneous. The conservation status of species is also discussed, regionally, nationally, and globally.


2020 ◽  
Author(s):  
Robert Starke ◽  
Maysa Lima Parente Fernandes ◽  
Daniel Kumazawa Morais ◽  
Iñaki Odriozola ◽  
Nico Jehmlich ◽  
...  

AbstractUnveiling the relationship between taxonomy and function in microbiomes is crucial to determine their contribution to ecosystem functioning. However, while the relationship between taxonomic and functional diversity in bacteria and fungi was reported, this is not the case for archaea. Here, we used a meta-analysis of completely annotated extant genomes of 417 taxonomically unique archaeal species to describe intergenome and intragenome redundancy of functions and to predict the extent of microbiome functionality on Earth contained within archaeal genomes using accumulation curves of all known functions from the level 3 of KEGG Orthology. We found that intergenome redundancy as functions present in multiple genomes was inversely related to intragenome redundancy as multiple copies of a gene in one genome, implying the trade of between additional copies of functionally important genes or a higher number of different genes. A logarithmic model described the relationship between functional diversity and species richness better than both the unsaturated and the saturated model, which suggests a limited total number of archaeal functions in contrast to the potential of bacteria and fungi. Using a global archaeal species richness estimate of 13,159, the logarithmic model predicts a total of 4,164.1 ±2.9 KEGG level 3 functions while the non-parametric bootstrap estimate yields a lower bound of 2,994 ±57 KEGG level 3 functions. Our approach not only highlights similarities in functional redundancy but also the difference in functional potential of archaea compared to other domains of life.


Author(s):  
M. Kumar ◽  
K. C. Siju

This paper presents the Bayesian analysis of the stress–strength reliability of a parallel system with active and mixed standby components. The Bayesian estimators of the parameters of exponential and Weibull stress–strength distributions are obtained by assuming informative and noninformative prior for the parameters of the respective distributions. The Gibbs sampling procedure is used to compute the Bayesian stress–strength reliability. The asymptotic distributions, of the maximum likelihood estimators of the parameters of the corresponding distributions, and of the respective system reliabilities are presented. The bootstrap estimate and confidence interval are also obtained. The procedures are illustrated based on certain datasets.


Author(s):  
L. Alfonso ◽  
F. Caleyo ◽  
J. M. Hallen ◽  
J. Araujo

The approach proposed by Najjar and coworkers for the prediction of maximum pit depth is applied and validated through direct comparison with real pipeline steel pitting corrosion data. This methodology combines the Generalized Lambda Distribution (GLD) and the Bootstrap Method (BM) in order to estimate both the maximum pit depth and confidence intervals associated with the estimation. Samples are drawn from real-life pitting corrosion data and the GLD is used to obtain modeled pit depth distributions emulating the experimental ones. In order to estimate the maximum pit depth over an N-times larger area, simulated distributions, N-times larger than the experimental ones, are generated 104 times. The deepest pit depth is extracted from each simulated bootstrap sample to obtain a dataset of 104 extreme pit-depth values. An estimate of the maximum pit depth for the N-times larger surface can be obtained from this dataset by calculating the average of the 104 extreme values. The uncertainty in the estimation is derived from the 95% confidence interval of the bootstrap estimate. In this report, the results of the application of the GLD-BM framework are compared with extreme pit depth values observed in real pitting corrosion data. The agreement between the estimated and actual maximum pit depths points to the applicability of the GLD-BM as an alternative in estimating the maximum pit depth when only a small number of samples are available. The main advantage of the combined methodology over the Gumbel method is its great simplicity, since fast and reliable estimations can be made with at least only two experimental samples.


2009 ◽  
Vol 27 (34) ◽  
pp. 5707-5712 ◽  
Author(s):  
Gabrielle Werkoff ◽  
Eric Lambaudie ◽  
Eric Fondrinier ◽  
Jean Levêque ◽  
Fréderic Marchal ◽  
...  

Purpose Three models have been developed to predict four or more involved axillary lymph nodes (ALNs) in patients with breast cancer with one to three involved sentinel lymph nodes (SLNs). Two scores were developed by Chagpar et al (Louisville scores excluding or including method of detection), and a nomogram was developed by Katz et al. The purpose of our investigation was to compare these models in a prospective, multicenter study. Patients and Methods Our study involved a cohort of 536 patients having one to three involved SLNs who underwent ALN dissection. We evaluated the area under the receiver operating characteristic curve (AUC), calibration (for the Katz nomogram only), false-negative (FN) rate, and clinical utility of the three models. Results were compared with the optimal logistic regression (OLR) model that was developed from the validation cohort. Results Among the 536 patients, 57 patients (10.6%) had ≥ four involved ALNs. The AUC for the Katz nomogram was 0.84 (95% CI, 0.81 to 0.86). The Louisville score excluding method of detection was 0.75 (95% CI, 0.72 to 0.78). The Louisville score including method of detection was 0.77 (95% CI, 0.74 to 0.79). The FN rates were 2.5% (eight of 321 patients), 1.8% (two of 109 patients), and 0% (zero of 27 patients) for the Katz nomogram and the Louisville scores excluding and including method of detection, respectively. The Katz nomogram was well calibrated. Optimism-corrected bootstrap estimate AUC of the OLR model was 0.86. Using this result as a reasonable target for an external model, the performance of the Katz nomogram was remarkable. Conclusion We validated the three models for their use in clinical practice. The Katz nomogram outperformed the two other models.


2009 ◽  
Vol 39 (2) ◽  
pp. 677-689
Author(s):  
Huijuan Liu ◽  
Richard Verrall

AbstractThis paper considers the bootstrapping approach for measuring reserve uncertainty when applying the model of Schnieper for reserves which separate Incurred But Not Reported (IBNR) and Incurred But Not Enough Reserved (IBNER) claims. The Schnieper method has been explored in Liu and Verrall (2009), and the Mean Square Errors of Prediction (MSEP) derived. This paper takes this further by deriving the full predictive distribution, using bootstrapping. Numerical examples are provided and the MSEP from the bootstrapping approach are compared with those obtained analytically.


2007 ◽  
Vol 55 (1) ◽  
pp. 124-146
Author(s):  
N. Lalitha ◽  
D.N. Rao

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