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The phosphorus retention ability of soils depends on several factors and influences the effectiveness of fertilization as well as the release of P from soil to water. In the present study the phosphorus supplying and/or retention ability of soils were estimated by two approaches: biological approach (pot experiments) and modelling (by regression analyses). In the course of the biological approach pot experiments were carried out with soils showing significant differences in total and available P contents. Soil samples were collected from selected plots of 9 sites of the National Long-Term Fertilization Trials (NLFT) after 20 years of fertilization, which represents different agro-ecological regions of Hungary. Site characteristics covered a wide range in pH, carbonate and P content, representing typical soil types of the country. With the statistical approach (modelling), the most important soil properties were included and the role of these factors was evaluated by stepwise regression analyses. From the equations, the contribution of important soil parameters to phosphorus supplying and retention ability could be quantified. The objective of the present study was to find a simple way to compare and evaluate the two approaches in P nutrient turnover of soils. Results of the two approaches were correlated. From these results, a rank correlation was also made from the experimental and calculated results. A very close relationship was observed for the P supply and retention of soils (r value was 0.918 for the N 0 P 0 K 0 unfertilized control and 0.927 for the N 200 P 200 K 100 fertilization level). Values obtained with rank correlation were 0.87 and 0.866, respectively, verifying that both methodologies are reliable for estimating the nutrient dynamics in soils and to predict P dynamics in a diverse range of soils.

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The retention (R M) values of nine one-point adsorption model compounds: diphenylamine, indol, 2-naphtol, 1-naphtol, 1-naphtylamine, 4-toluidine, carbazole, 4-chloraniline, and thymol were investigated on silica gel using six modifiers: acetone, dioxane, hexane, isopropanol, methylethylketone, ethyl acetate, and tetrahydrofurane (in hexane). These compounds showed small but visible curvilinearity of dependence of R M vs. modifier concentration. This curvilinearity is very similar among the investigated compounds, so relative differences of extrapolated R M are almost the same (strictly intercorrelated) regardless of the regression technique used. We have compared several robust and weighted regression methods and investigated their impact on extrapolated values. It can be concluded that one should primarily consider weighted regression with 1/x weights during retention extrapolation. It seems to be a better alternative than classical regression (better extrapolation) and also better than polynomial approaches (better stability).

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A szomatosztatinanalóg-kezelés a neuroendokrin daganatok terápiájának egyik sarokköve. A hormontermelés gátlásában hatékonysága jól ismert, de újabb adatok a daganatnövekedést gátló hatását is alátámasztják. A szerzők májáttétet adó 1-es típusú gyomor neuroendokrin daganatban szenvedő nő kórtörténetét ismertetik, akinél a szomatosztatinanalóg-kezelés két éven belül mind a gyomorfolyamat, mind a májáttétek teljes regresszióját váltotta ki. Az eset felhívja a figyelmet arra, hogy a szomatosztatinanalóg-kezelés nemcsak a hormonális tünetek, hanem a daganat növekedésének gátlásában is eredménnyel alkalmazható. Orv. Hetil., 2011, 152, 407–410.

Open access

Abstract  

The aim of this study was to correlate the results of experimental data using DTA method and predictions of artificial neural network (ANN) and multivariate linear regression (MLR). Thermal decomposition of polymers was analyzed by simultaneous DTA method, and kinetic parameters (critical points, the change of enthalpy and entropy) of polymers were investigated. A computer model based on multilayer feed forwarding back propagation and multilayer linear regression model were used for the prediction of critical points, phase transitions of low-density polyethylene (LDPE) and mid-density polyethylene. As a result of our study, we concluded that ANN model is more suitable than MLR about prediction of experimental data.

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Férfi fizikai dolgozók testösszetételének jellemzői: középpontban az életkor

Body compositions characteristic in male manual workers: age as a central factor

Orvosi Hetilap
Authors:
Zsolt Szakály
,
Zsófia Pápai
,
Zsuzsanna Liszkai
,
József Bognár
, and
Csaba András Dézsi

Bevezetés: A hazai morbiditási és mortalitási statisztikák szerint a megbetegedési struktúrában átrendeződés mutatkozik. Napjainkra azok a betegségek lettek egyre gyakoribbak, amelyek kialakulásában az életmód szerepe jelentős. Ezért az egészségkockázati tényezők detektálása a különböző életkori, nemi és egyéb csoportok mentén kiemelt feladat. Célkitűzés: A kutatás célja férfi fizikai dolgozók egészségi állapottal összefüggő antropometriai változóinak életkori csoportok szerinti bemutatása és a kritikus életkori szakaszok kijelölése. Módszer: Vizsgálatunkba önkéntes alapon férfi fizikai dolgozókat vontunk be (n = 179 fő). A testösszetételt Inbody 720 eszközzel vizsgáltuk. A mért és a számított jellemzők közül a testtömegindexet, a relatív izom- és zsírtömeget, a derék-csípő arányt és a zsigeri zsírt vontuk be. A vizsgált változók korfüggését lineáris regressziós analízissel, a változók közötti kapcsolatot korrelációs együtthatóval jellemeztük. Eredmények: Az antropometriai változók jelentős része nem az egészséges tartományon belül helyezkedik el. A változók mindegyikénél kimutatható a korfüggés, kritikusnak mondható életkort vagy életkori szakaszt azonban nem tudtunk kijelölni. Az alkalmazott antropometriai módszerek kapcsolata szignifikáns. Megbeszélés: A férfi fizikai dolgozók között az életkortól függetlenül nagy számban detektálhatók olyanok, akiknek a testösszetétele egyértelmű egészségi kockázatot jelent. Következtetés: A kockázat csökkentése érdekében komplex munkahelyi egészségfejlesztő programok indítása szükséges. A megvalósítás során minden korosztálynál fontos szempont az aktív és egészségtudatos életmód kialakítása. Orv Hetil. 2023; 164(3): 96–103.

Open access

Poetics of infinite regress

Narrative abrogation in Zola’s Nana

Neohelicon
Author:
R.-L. Barnett

Abstract  

Within the tangled skein of Zola’s Nana, malady—metaphysical and metaphorical—yields but violated debris: a disassemblage of annexed marginalia, bits of flesh, disinherited, as it were, and subsisting in the absence of all signifying matter. So with discourse. It, likewise, transpires as a breed of involuted play, a repository of ill-defined wantingness, an interstice, an illusion, oxymoron, annulation, oneiric absence—until it slakes perniciously into silence. To the extent that readability (the infamous “lisible”) is constructed largely upon some brand of referential chain (even in its post-modern, intratextual demeanors), the disintegration of the novel’s nuclear substance un-does, in a very real sense, any brand of integrality. As the inexorable “virus” eviscerates and strips away the actrice, the theater, the stage, the visage of Venus, the play, the script, the auto-referentiality of narcissistic glances, the vituperative glare of those “perdu[s] derrière les jupes,” in sum, the very matter of the exposé (énoncé and énonciation), we, as readers, are extradited to the margins of discourse, left at an end, at the end with none but the somatic vestiges of Zola’s bloat queen, whose deleted marrow is the only marrow that there is, usurping the text and, ultimately, the contours of its own ravaged frame. Yet there lurks, all else effaced, this “monstre de l’Écriture, lubrique, sentant la fauve”: Zola’s epithetic turn of phrase, the genitive pitting of beastliness and textliness, significantly repeals difference and proffers a conjunctive vision of word and world withered.

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The aim of this study was to prove if oxidation-reduction levels in the follicular fluid were new functional indices of follicular health and whether there was a high level of accordance with endocrinological parameters and with the growth stage as detected by ultrasound monitoring of individual follicles during the oestrous cycle in mares. Follicles were classified as growing and regressing follicles using ultrasonography. Altogether 48 follicles with a diameter from 20 to 56 mm were aspirated by transvaginal ultrasound guided follicular aspiration. Follicular concentration of oestradiol and progesterone in relation to the diameter of growing follicles showed correlations of r = 0.64 and r = 0.57, respectively. The redox potential derived index D2 varied from -448 to +431 in the collected fluids of the follicles. The accordance of the judgement of all follicles using both complexes of methods - endocrinological and ultrasonographic parameters vs. analysis of oxidation and reduction levels - reached 72.5%. This finding has shown that parameters of redox reactions do not correlate closely with the stage of follicular growth or regression as determined by in vivoscanning of ovaries or by assessment of follicular steroid concentrations. However, the measurement of redox potentials offers an opportunity to examine the whole process of metabolism in follicular cells and to forecast impairments of cellular performances. Changes of redox parameters in growing follicles enable an earlier prediction of their further development. The data demonstrate that growing and regressing follicles do not represent nonatretic, early atretic and atretic follicles, respectively.

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The quality of bioanalytical data is highly dependent on selection of an appropriate regression model for calibration plots. In bioanalytical assays, variance normally increases with concentration. Use of a traditional approach with heteroscedastic data will lead to impaired accuracy. To take heteroscedasticity into account, transformation and weighting approaches have been used to generate the calibration plots. A new, simple, rapid, sensitive, and accurate HPTLC method has been established for the estimation of aceclofenac in plasma. Protein precipitation with acetonitrile was used for extraction. Chromatography was performed on silica gel 60F 254 plates with toluene-ethyl acetate-methanol-glacial acetic acid 7:2:2:0.1 ( v/v ) as mobile phase. Aceclofenac was quantified in reflectance-absorbance mode at 270 nm. Aceclofenac-to-external standard peak-area ratio, for plasma, was used as a linear function of concentration over the range 0.8 to 14 μg mL −1 . Average relative residual at each point of the calibration plot combined with accuracy and precision for quality-control samples were compared using the parameter rank approach. 1/ x 2 weighted regression model gave better estimates with smaller relative residuals and the best accuracy and precision compared with other models.

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Abstract  

Thermal behavior of nitroguanidine (NQ) has been investigated by TG/DSC-MS-FTIR simultaneous analysis performed under both isothermal and nonisothermal conditions. The isothermal test at 230 °C indicated that the release of gas products can be divided into several stages. The processing of the non-isothermal data, namely 5, 10, 15, and 20 K/min, was performed by using Netzsch Thermokinetics. The dependence of the activation energy evaluated by Friedman’s isoconversional method on the conversion degree shows that the investigated process is complex one, and can be divided into three parts. The mechanism of the process and the corresponding kinetic parameters were determined by Multivariate Non-linear Regression Program. The kinetic results was used to simulate the thermal decomposition of NQ under isothermal condition at 210 °C. The simulated curve is in agreement with the tested curve. The obtained results were also used for prediction of the thermal lifetime of NQ corresponding to a certain temperature.

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This study investigated microhabitat relationships of terrestrial bryophytes in a subalpine forest of coastal British Columbia. Substratum affinities were characterized for dominant bryophytes. Logistic regression analysis was used to gain insight into the ecological determinants of fine scale (0.1 m2) bryophyte distribution by examining the predictive relationship between bryophyte species occurrence and localized environmental conditions, as well as the coverage of other bryophytes. The predictive relationships were compared to evaluate the relative importance of environmental factors versus interspecific interactions in structuring bryophyte communities. The results indicate that bryophytes show unique responses in their relationships to environmental conditions and other bryophytes. Positive feedback appears to be an important process among terrestrial bryophytes in subalpine forests.

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