scholarly journals A Precise Determination of Some Critical Terms in the Solar System

1979 ◽  
Vol 81 ◽  
pp. 91-93
Author(s):  
Jean Chapront ◽  
Rudolf Dvorak
Keyword(s):  
Perturbation Theory ◽  
Solar System ◽  
High Precision ◽  
Precise Determination ◽  
Small Divisors ◽  
The Mean ◽  
New Form ◽  
Very High

A new form to determine the contribution of some special small divisors in perturbation theory is presented in this paper. We can avoid to calculate all the kλ+k′λ as it has to be done normally (λ and λ′ designate the mean longitudes of the two regarded planets). For a chosen k and k′ we calculate with a very high precision the contribution to the perturbation of the elements with the aid of the Hansen's coefficients.

scholarly journals Orexitropic Signaling Proteins in Obese Children

2007 ◽  
Vol 7 ◽  
pp. 1263-1271 ◽  
Author(s):  
Ljiljana Saranac ◽  
Bojko Bjelakovic ◽  
Hristina Stamenkovic ◽  
Borislav Kamenov
Keyword(s):  
Body Mass ◽  
Central Obesity ◽  
Energy Homeostasis ◽  
Leptin Resistance ◽  
Signaling Proteins ◽  
Obese Children ◽  
Significant Difference ◽  
The Mean ◽  
Very High

Adipose tissue is not only the main organ for energy storage, but it also has endocrine properties, producing “adipokines” responsible for energy homeostasis, insulin sensitivity, and inflammation. Leptin, produced by adipocytes, is the key hormone in appetite regulation and suppression of orexigenic, hypothalamic neuropeptide Y (NPY). We wanted to establish and compare levels of leptin and NPY in different obesity types in childhood, and to investigate their correlations with auxological parameters. Twenty-one obese children (seven girls and 14 boys), divided into two groups, were compared with 14 controls. The mean age of the study group was 10.81 ± 3.69 years and the mean puberty stage was 2.21. The mean body mass index (BMI) was 32.80 kg/m2(range 23.30– 47.02) and the mean overweight 30.73 kg (range 8.00–74.00). The mean leptin level was higher in boys and in the group with central obesity, but was not significant. Leptin/NPY ratio and leptin/BMI ratio was also higher in the central obesity group and there was a more significant difference compared with controls. We found significant correlation of the leptin level with body mass (BM), body mass excess (BME), and BMI (p < 0.05). The mean leptin level in obese children was very high (36.39 ng/ml). Leptin and NPY levels showed inverse values in two different obesity types. Results are suggestive for leptin resistance rather than leptin deficiency in our group of obese children. Orexitropic signaling proteins correlated significantly with auxological parameters. Determination of the leptin and NPY concentrations provided evidence that obesity represents disease with neuroendocrine dysfunction and high leptin/NPY ratio, which could be a useful marker for central obesity.

scholarly journals An experiment with the balance to find if change of temperature has any effect upon weight

1905 ◽  
Vol 76 (512) ◽  
pp. 445-457 ◽  
Keyword(s):  
Low Temperatures ◽  
Secondary Effect ◽  
Boiling Liquid ◽  
The Earth ◽  
Exact Determination ◽  
The Mean ◽  
Very High ◽  
The Ideal

In all the experiments hitherto made to determine the gravitative attraction between two masses, the temperature has not varied more than a few degrees, and there are no results which would enable us to detect with certainty any dependence of attraction upon temperature even if such dependence exists. It is true, as Professor Hicks has pointed out, that Baily’s results for the Mean Density of the Earth, if arranged in the order of the temperature of the apparatus when they were obtained, show a fall in value as the temperature rises. But this is almost certainly some secondary effect, due to errors in the measurements of the apparatus, or to the seasons at which different attracted masses were used. The ideal experiment to find if temperature has an effect on gravitation would consist in one determination of the gravitative attraction between two masses at, say 15°C., and another determination at, say, the temperature of boiling liquid air. But the difficulties of exact determination at ordinary temperatures are not yet overcome, and at any very high or very low temperatures, they would be so much increased that the research seems at present hopeless.

Carbon tetrachloride poisoning in sheep: Effect upon the serum E260 value and plasma volume

1962 ◽  
Vol 13 (6) ◽  
pp. 1073 ◽  
Author(s):  
CH Gallagher
Keyword(s):  
Carbon Tetrachloride ◽  
No Value ◽  
Plasma Volume ◽  
Stomach Tube ◽  
Ccl4 Poisoning ◽  
The Mean ◽  
The One ◽  
Diagnostic Criterion ◽  
Very High

Serum E260 values were determined at intervals in sheep which were given 50 ml carbon tetrachloride (CCl4) by stomach tube into the rumen, and in untreated sheep. After administration of the drug, the mean E260 value fell initially, being minimal at 3 hr. At this time, the circulating plasma volume had increased by one-fifth, and it is considered that this dilution factor largely explained the fall. The group mean for non-fatal cases rose above the pre-administration level at 7 hr, then returned to it by 24 hr. However, in the one sheep that died from CCl4 poisoning, the serum E260 value remained very high until death at 46 hr. In view of the significant variations in serum E260 values between untreated sheep, and the significant random variations in serum E260 values between times of bleeding such sheep, it is concluded that the determination of serum E260 values at isolated times in individual sheep is of no value as a diagnostic criterion of CCl4 poisoning.

Computer determination of thoracic gas volume using plethysmographic "thoracic flow"

1980 ◽  
Vol 48 (5) ◽  
pp. 911-916 ◽  
Author(s):  
H. Lorino ◽  
A. Harf ◽  
G. Atlan ◽  
Y. Brault ◽  
A. M. Lorino ◽  
...  
Keyword(s):  
Regression Line ◽  
Time Derivative ◽  
Thoracic Gas Volume ◽  
Mouth Pressure ◽  
Computer Determination ◽  
The Subject ◽  
The Mean ◽  
Gas Volume ◽  
Very High

Plotting a line to the variables obtained during a panting maneuver, i.e. thoracic volume and mouth pressure, is the conventional way of computing plethysmographic thoracic gas volume (TGV). This procedure is reliable if the magnitude of the thoracic volume changes is large compared to the drift on the signal; this is one of the major problems in volumetric plethysmography. We propose replacing the thoracic volume signal (Vt) by its time derivative (Vt) and similarly mouth pressure (Pm) with its time derivative (Pm). Drift is thus ruled out, and the magnitude of Vt is preserved when the subject fails to carry out noticeable changes in thoracic volume during the panting, since even then the speed of these changes in thoracic volume remains high. The use of Vt and Pm appeared to be necessary when a minicomputer was connected to a pressure-compensated flow plethysmograph to obtain an automatic calculation of TGV. A regression-line technique applied to signals obtained during the panting was used to find the slope of the relation and thus TGV. However, this slope can only be predicted with less than 5% error if the correlation coefficient is very high (i.e., above 0.99). The analysis of 121 recordings from patients showed that the mean r was only 0.954 when Vt and Pm were used. It increased to 0.993 with Vt and Pm. For the same recordings the comparison of hand-calculated TGV and computer-derived TGV showed a much better agreement for the Vt-Pm method (standard error of the estimate (SEE) = 0.14 liter) than for the Vt-Pm method (SEE = 0.34 liter). These results emphasize that, in contrast to the manual technique, the computer does not adequately handle even a small drift of the thoracic signal. The proposed time-derivative method is therefore useful for a hand calculation, but essential to a reliable computer determination of thoracic gas volume.

Studying, Working, and Living in Another EU Country

2000 ◽  
Vol 5 (3) ◽  
pp. 216-227 ◽  
Author(s):  
Etienne Mullet ◽  
Véronique Dej ◽  
Isabelle Lemaire ◽  
Philippe Raïff ◽  
Jolyon Barthorpe
Keyword(s):  
Factor Analysis ◽  
United Kingdom ◽  
Family Influence ◽  
Eu Countries ◽  
The United Kingdom ◽  
Confirmatory Factor ◽  
The Family ◽  
The Mean ◽  
Very High

This study assessed the willingness of French youth to go and study or work for some time in another EU country. We examined three types of questions: (a) What is the overall level of willingness to go in another EU country? Does age, gender or socioeconomic status (SES) of the family influence this overall level? Which country do French youth prefer to go to? (b) Is a four-factor Push-Anti-Push-Pull-Anti-Pull model able to account for data regarding attitudes toward other countries and attitudes toward France? (c) Is this model able to predict willingness to go and study or work in another EU country, both generally and for individual countries? The overall level of willingness to go to other EU countries was not very high. Except for the United Kingdom the mean response was always located closer to the “No” pole than to the “Quite possible” pole. Gender, age, and educational level of the father did not play a role. Participants clearly preferred the United Kingdom and Spain to Germany or The Netherlands. Exploratory factor analysis showed a clearly interpretable Push-Anti-Push-Pull-Anti-Pull solution, and confirmatory factor analysis showed that this structure fits the attitudes data very well according to the usual indices. This general model, however, did not explain much of the “intent-to-go” variance. In addition, specific Pull attractiveness considerations (liking and knowing the country) played, beyond the general Push-Pull model, a notable role in the determination of willingness to go and study or work in each of the 14 EU countries.

UNTERSUCHUNGEN ÜBER DIE TETRAHYDROALDOSTERON AUSSCHEIDUNG IM KINDESALTER DURCH GASCHROMATOGRAPHIE MIT ELEKTRONENEINFANGDETEKTOR (ECD)

1972 ◽  
Vol 70 (3) ◽  
pp. 533-551 ◽  
Author(s):  
J. Solc ◽  
D. Knorr
Keyword(s):  
Sodium Intake ◽  
Active Phase ◽  
Strong Increase ◽  
Gas Liquid Chromatography ◽  
Aldosterone Secretion ◽  
Infancy And Childhood ◽  
The Mean ◽  
Potassium Loading ◽  
Very High

ABSTRACT Tetrahydroaldosterone-(THAldo)-glucuronide is the most important metabolite of aldosterone in the urine. According to Nicolis & Gabrilove (1969) we developed a GLC method for the determination of THAldo. The method includes the following steps: Enzymatic hydrolysis, extraction with ethylacetate, formation of γ-lactone, first TLC, formation of heptafluorobutyrate (HFB), second TLC, gas liquid chromatography (GLC) with electron capture detector (ECD), correction for losses by the internal 3H-THAldo standard. As little as 3 ng/sample can be detected with a coefficient of variation of < 10%. The paper presents more than 300 THAldo determinations during infancy and childhood. At the age of 5–30 days there is a significant (P < 0.01) peak of the THAldo excretion. The biological meaning of these high THAldo values in the early days of life is not clear at the present time. The peak is independent of the nutrition. After the age of 12 months the mean THAldo excretion is about 30 μg/m2/d. There is a circadian rhythm with a peak in the late morning. The dependence of the THAldo excretion on the sodium intake in childhood is the same as in adults. After potassium loading there is likewise a strong increase in the THAldo excretion. In a child suffering from Addison's disease we found about 30% of the substituted aldosterone as THAldo-glucuronide in the urine. As well angiotensin as ACTH induce an increase of the THAldo excretion. After dexamethasone there is a decrease of THAldo excretion indicating again an ACTH dependence of the aldosterone secretion. Children suffering from nephrotic syndrome during the active phase of the disease show very high values of THAldo in the urine. Under treatment with corticosteroids the THAldo excretion decreases depending on the remission. Treatment with both furosemide and potassium induces again a sharp increase of the THAldo excretion.

scholarly journals “Perfecting” pure shift HSQC: full homodecoupling for accurate and precise determination of heteronuclear couplings

2014 ◽  
Vol 50 (99) ◽  
pp. 15702-15705 ◽  
Author(s):  
L. Kaltschnee ◽  
A. Kolmer ◽  
I. Timári ◽  
V. Schmidts ◽  
R. W. Adams ◽  
...  
Keyword(s):  
High Precision ◽  
Precise Determination ◽  
Proton Proton

Full suppression of proton–proton couplings in pure shift HSQC spectra simplifies their analysis, as demonstrated for high precision RDC measurements.

One Step Closer towards a Reliable Tinnitus Pitch-Match Frequency Determination Using Repetitive Recursive Matching

2020 ◽  
Vol 25 (4) ◽  
pp. 190-199 ◽  
Author(s):  
Daniela Korth ◽  
Andreas Wollbrink ◽  
Robert Wunderlich ◽  
Daniela Ivansic ◽  
Orlando Guntinas-Lichius ◽  
...  
Keyword(s):  
Internal Consistency ◽  
Choice Test ◽  
Test Results ◽  
Outlier Identification ◽  
Excellent Internal Consistency ◽  
One Step ◽  
Matching Procedure ◽  
The Mean ◽  
Very High

Introduction: The determination of the tinnitus pitch-match (PM) frequency is not straightforward but an important audiological assessment recommended for clinical and research purposes. We evaluated repetitive recursive matching using an iPod-based matching procedure as a method to estimate a patient’s PM frequency without audiometric equipment. Methods: One hundred and seventeen patients with chronic tonal tinnitus (uni- and bilateral tinnitus) measured their tinnitus in 10 sessions using a self-administered automated iPod-based procedure comprising a recursive 2 interval forced-choice test. Results: Mean SD of the PM frequency of all participants across sessions was 0.41 octaves. The internal consistency measured by Cronbach’s α was very high (0.8–>0.95). As an example, 7 PMs obtained excellent internal consistency (α = 0.93). The exclusion of the first and/or second session led to more definite PMs with a decreased SD. Outliers were identified by PMs departing 2 SDs (i.e., 0.94 octaves) from the mean variability (n = 5). Conclusion: Repetitive recursive matching together with recommendations for the exclusion of initial and redundant sessions as well as outlier identification and treatment can enable a reliable estimation of the PM frequency.

"Zero" and "Off-Zero" Critical Concentrations in Solutions of Polydisperse Polymers with Very High Molar Masses

1995 ◽  
Vol 60 (10) ◽  
pp. 1661-1688 ◽  
Author(s):  
Karel Šolc ◽  
Karel Dušek ◽  
Ronald Koningsveld ◽  
Hugo Berghmans
Keyword(s):  
Perturbation Theory ◽  
Half Plane ◽  
Diphenyl Ether ◽  
Order Perturbation ◽  
Order Perturbation Theory ◽  
Critical Concentrations ◽  
Quadratic Interaction ◽  
Region Ii ◽  
Very High

Polymer solutions with a concentration-dependent interaction parameter g(ϕ) are known to have sometimes critical polymer concentrations ϕc converging to a non-zero value (a so-called "off-zero" limiting critical point (CP)), as the chain length, m, grows to infinity, rather than to zero as usual (a "zero" limiting CP). In this report the criteria for the existence of both types, known for binary solutions with a linear g = g0 + g1ϕ, are extended to cover polydisperse polymers with a quadratic interaction function g(ϕ). Its coefficients g2 and ∆g2 = g2 - g1 determine the number and type of limiting CPs. Accordingly, the plane g2, ∆g2 is divided into the regions I (a zero CP), II (an off-zero CP), and III (a zero + two off-zero CPs). The region II is restricted to the half-plane with ∆g2 < -1/6, whereas the other half-plane with ∆g2 > -1/6 is shared by I and III. By varying the interactions, two limiting CPs may be brought together and merged in a heterogeneous double limiting CP. Such instances define the boundaries between the regions: at the I/III line, two off-zero CPs merge, whereas at the II/III line an off-zero CP coincides with a zero CP. A first-order perturbation theory of the latter double CPs, and a second-order perturbation theory of single "zero" CPs are developed, enabling meaningful extrapolations of data on polymers with high but finite molar masses. The latter theory yields extrapolation formulas for determination of Η-temperature, taking into account the polymer polydispersity and the concentration dependence of g. Solutions of polyisobutene in diphenyl ether and, possibly, in benzene appear to present experimental examples of off-zero limiting critical concentrations.

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