3,739 research outputs found
How local crustal thermal properties influence the amount of denudation derived from low-temperature thermochronometry: Reply
No abstract available
Estimation of reference intervals from small samples: an example using canine plasma creatinine
Background: According to international recommendations, reference intervals should be determined from at least 120 reference individuals, which often are impossible to achieve in veterinary clinical pathology, especially
for wild animals. When only a small number of reference subjects is available, the possible bias cannot be known and the normality of the distribution cannot be evaluated. A comparison of reference intervals estimated by different methods could be helpful.
Objective: The purpose of this study was to compare reference limits determined from a large set of canine plasma creatinine reference values, and large subsets of this data, with estimates obtained from small samples selected randomly.
Methods: Twenty sets each of 120 and 27 samples were randomly selected from a set of 1439 plasma creatinine results obtained from healthy dogs in another study. Reference intervals for the whole sample and for the large
samples were determined by a nonparametric method. The estimated reference limits for the small samples were minimum and maximum, mean +/-2 SD of native and Box–Cox-transformed values, 2.5th and 97.5th percentiles by a robust method on native and Box–Cox-transformed values,
and estimates from diagrams of cumulative distribution functions.
Results: The whole sample had a heavily skewed distribution, which approached Gaussian after Box–Cox transformation. The reference limits estimated from small samples were highly variable. The closest estimates to
the 1439-result reference interval for 27-result subsamples were obtained by both parametric and robust methods after Box–Cox transformation but were grossly erroneous in some cases.
Conclusion: For small samples, it is recommended that all values be reported graphically in a dot plot or histogram and that estimates of the reference limits be compared using different methods
Centrality Dependence of Bulk Fireball Properties at RHIC
We explore the centrality dependence of properties of the dense hadronic
matter created in \sqrt{s_{NN}}=200 GeV Au--Au collisions at RHIC. Using the
statistical hadronization model we fit particle yields known for 11 centrality
bins. We present the resulting model parameters, rapidity yields of physical
quantities and the physical properties of bulk matter at hadronization as
function of centrality. We discuss the production of strangeness and entropy.Comment: 7 pages including 5 figures, 1 table: more information provided:
figure 1 in lieu of work in progress defines phi-data, table for statistical
parameters for all models as function of centrality, additional references
and reference update, section captions, PRC `nearly to be published'.... look
out for further updates, referees run amoc
Validation of the Medonic CA620/530 Vet 20-ml microcapillary sampler system for hematology testing of feline blood
The aim of the current study was to compare feline hematologic variables in blood collected in
microcapillary tubes (20 ml) and conventional blood tubes with the Medonic CA620/530 Vet in-house
hematologic analyzer. A comparison of results obtained in 60 cats presented at the clinics of the veterinary
school showed that the correlations between the 2 methods were 0.97 for white blood cell, 0.95 for red blood
cell, and 0.93 for platelet counts; 0.92 for hemoglobin concentration; and 0.99 for mean corpuscular volume.
No clinically relevant differences between the 2 blood sampling techniques were observed for any variable,
which suggests that both techniques are interchangeable in cats. Moreover, microcapillary tubes would allow
easier repeated sampling in the same cat and would likely be useful in other small species
Reference values: a review
Reference values are used to describe the dispersion of variables in healthy individuals. They are usually reported as population-based reference intervals (RIs) comprising 95% of the healthy population. International recommendations
state the preferred method as a priori nonparametric determination from at least 120 reference individuals, but acceptable alternative methods include transference or validation from previously established RIs. The most critical steps in the determination of reference values are the selection of reference individuals based on extensively documented inclusion and exclusion criteria and the use of quality-controlled analytical procedures. When only small numbers of values are available, RIs can be estimated by
new methods, but reference limits thus obtained may be highly imprecise. These recommendations are a challenge in veterinary clinical pathology, especially when only small numbers of reference individuals are available
Strangeness Chemical Equilibration in QGP at RHIC and LHC
We study, in the dynamically evolving QGP fireball formed in relativistic
heavy ion collisions at RHIC and LHC, the growth of strangeness yield toward
and beyond the chemical equilibrium. We account for the contribution of the
direct strangeness production and evaluate the thermal-QCD strangeness
production mechanisms. The specific yield of strangeness per entropy, s/S, is
the primary target variable. We explore the effect of collision impact
parameter, i.e., fireball size, on kinetic strangeness chemical equilibration
in QGP. Insights gained in study the RHIC data with regard to the dynamics of
the fireball are applied to the study strangeness production at the LHC. We use
these results and consider the strange hadron relative particle yields at RHIC
and LHC in a systematic fashion. We consider both the dependence on s/S and
directly participant number dependence.Comment: 21 pages, 13 figures, PRC in press. Strangeness production recomputed
with K-factor K=1.7. Particle yields recomputed with SHARE 2.
Canine reference intervals for coagulation markers using the STA Satellite and the STA-R Evolution analyzers
The aim of the current study was to determine canine reference intervals for prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, and antithrombin (AT) according to international recommendations. The STA Satellite coefficients of variation of within-laboratory imprecision were 3.9%, 1.3%, 6.9%, and 5.1% for PT, APTT, fibrinogen, and AT, respectively. At 4uC, citrated specimens were stable up to 8 hr for whole blood and 36 hr for plasma, except for APTT, which increased slightly (<1 sec). Nonparametric reference intervals determined in citrated plasma from 139 healthy fasting purebred dogs were 6.9–8.8 sec, 13.1–17.2 sec, 1.24–4.30 g/l, and 104–188% for PT, APTT, fibrinogen, and AT, respectively. Based on Passing–Bablok comparison between STA Satellite and STA-R Evolution using 60 frozen specimens from a canine plasma bank, the corresponding reference intervals were transferred to the STA-R Evolution: 7.1–9.2 sec, 12.9–17.3 sec, 1.20–4.43 g/l, and 94–159% for PT, APTT, fibrinogen, and AT, respectively
Half-Reeb components, Palais-Smale condition and global injectivity of local diffeomorphisms in R3
Let F = (F1, F2, F3): R3 → R3 be a C∞ local diffeomorphism. We prove that each of the following conditions are sufficient to the global injectivity of F: A) The foliations FFi made up by the connected components of the level surfaces Fi = constant, consist of leaves without half-Reeb components induced by Fj , j ∈ {1, 2, 3} \ {i}, for i ∈ {1, 2, 3}.B) For each i 6= j ∈ {1, 2, 3}, Fi $l : L → R satisfy the Palais-Smale condition, for all L ∈ FFj. We also prove that B) implies A) and give examples to show that the converse is not true. Further, we give examples showing that none of these conditions is necessary to the global injectivity of F
- …