Search results for "Linear Model"
showing 10 items of 598 documents
Evaluation of furanocoumarins from seeds of the wild parsnip (Pastinaca sativa L. s.l.).
2018
Abstract Although the wild parsnip (Pastinaca sativa L. s.l.) fruits are known to contain linear and angular furanocoumarins, the individual components of the seeds have not been fully identified and quantitated, and, in the case of immature seeds, reported. In view of this, the main furanocoumarin compounds were extracted using pyridine, and were isolated using semi-preparative high-performance liquid chromatography. The structural elucidation of isolated compounds was done based on detailed spectral analysis conducted by liquid chromatography–electrospray ionization–mass spectrometry (LC–ESI/MS), 1H and 13C NMR and, where possible, by gas chromatography–mass spectrometry (GC–MS). The quan…
Serum leptin is associated with serum uric acid concentrations in humans.
1999
This cross-sectional study aimed to evaluate the relationship between leptin and the cluster of abnormalities often referred to as the metabolic syndrome. The serum leptin concentration, body mass index (BMI), percent body fat, total fat mass (FM), waist and hip circumference, waist to hip ratio (WHR), prevalence of hypertension, and triglyceride (TG), lipoprotein, and uric acid concentration were determined in 86 type 2 diabetic (n = 59) and healthy (n = 27) subjects. Multiple regression analyses showed that the estimates of total body obesity (BMI, percent body fat, and total FM), sex, and serum uric acid concentration are independently associated with the serum leptin concentration. The …
Climate and land-use changes as determinants of lesser kestrel Falco naumanni abundance in Mediterranean cereal steppes (Sicily)
2010
Monitoring of lesser kestrels Falco naumanni is necessary to promote conservation of this vulnerable species. To this end, 35 colonies of this species located in the NNW and SE of Sicily were monitored from 2003 to 2009. Counts of the active colonies and resident pairs were modelled by loglinear Poisson regressions to assess population trends over the study period. Afterwards, a GLM with an analysis of covariance design and a backward removal stepwise regression was performed to relate the observed trend to local- or global-scale climatic variation and to local land-use changes. Colony counts provided a better fit to the loglinear models than pair counts. Loglinear models separated the incr…
How to validate similarity in linear transform models of event-related potentials between experimental conditions?
2014
Abstract Background It is well-known that data of event-related potentials (ERPs) conform to the linear transform model (LTM). For group-level ERP data processing using principal/independent component analysis (PCA/ICA), ERP data of different experimental conditions and different participants are often concatenated. It is theoretically assumed that different experimental conditions and different participants possess the same LTM. However, how to validate the assumption has been seldom reported in terms of signal processing methods. New method When ICA decomposition is globally optimized for ERP data of one stimulus, we gain the ratio between two coefficients mapping a source in brain to two…
Immune-mediated change in the expression of a sexual trait predicts offspring survival in the wild.
2011
9 pages; International audience; BACKGROUND: The "good genes" theory of sexual selection postulates that females choose mates that will improve their offspring's fitness through the inheritance of paternal genes. In spite of the attention that this hypothesis has given rise to, the empirical evidence remains sparse, mostly because of the difficulties of controlling for the many environmental factors that may covary with both the paternal phenotype and offspring fitness. Here, we tested the hypothesis that offspring sired by males of a preferred phenotype should have better survival in an endangered bird, the houbara bustard (Chlamydotis undulata undulata). METHODOLOGY/PRINCIPAL FINDINGS: We…
Stir bar sorptive-dispersive microextraction for trace determination of triphenyl and diphenyl phosphate in urine of nail polish users
2018
Abstract This work describes a new analytical method useful for monitoring the human exposure to the endocrine-disrupting plasticizer triphenyl phosphate (TPP) via nail polish use. The method allows trace determination of this parent compound and its main metabolite, namely diphenyl phosphate (DPP), in urine samples of nail polish users. The method is based on a novel microextraction technique termed stir bar sorptive-dispersive microextraction (SBSDME) using a magnetic composite made of CoFe2O4 magnetic nanoparticles embedded into a mixed-mode weak anion exchange polymer (Strata™-X-AW), followed by liquid chromatography-tandem mass spectrometry (LC–MS/MS). The main parameters involved in t…
Sex–biased maternal investment in voles: importance of environmental conditions
2004
Adaptive bias in sex allocation is traditionally proposed to be related to the condition of mothers as well as to the unequal fitness values of produced sexes. A positive relationship between mother condition and investment into male offspring is often predicted. This relationship was also recently found to depend on environmental conditions. We studied these causalities experimentally using a design where winter food supply was manipulated in eight outdoor-enclosed populations of field voles Microtus agrestis. At the beginning of the breeding season in spring, food-supplemented mothers seemed to be in a similar condition, measured as body mass, head width, body condition index and parasite…
Severe reduction of blood lysosomal acid lipase activity in cryptogenic cirrhosis: A nationwide multicentre cohort study
2017
Background and aims Blood lysosomal acid lipase (LAL) is reduced in non-alcoholic steatohepatitis, which is the major cause of cryptogenic cirrhosis (CC); few data on LAL activity in CC do exist. We investigated LAL activity in a cohort of patients with liver cirrhosis. Methods This is a multicentre cohort study including 274 patients with liver cirrhosis of different aetiology from 19 centres of Internal Medicine, Gastroenterology and Hepatology distributed throughout Italy. Blood LAL activity (nmol/spot/h) was measured with dried blood spot extracts using Lalistat 2. Results Overall, 133 patients had CC, and 141 patients had cirrhosis by other causes (61 viral, 53 alcoholic, 20 alcoholic …
The Role of Liver in Determining Serum Colon-Derived Uremic Solutes.
2015
Evidence has shown that indoxyl sulfate (IS) and p-cresyl sulfate (PCS) may be alternative predictors of clinical outcomes in chronic kidney disease (CKD). Both toxins are derived from the gastrointestinal tract and metabolised in the liver. However, it is unclear whether the liver affects the production of IS and PCS. Here, we explore the association between IS and PCS levels in liver cirrhosis and a CKD-based cohort (N = 115). Liver and kidney function was assessed and classified by a Child-Pugh score (child A–C) and a modified version of the Modification of Diet in Renal Disease (MDRD) equation (Stages 1–4), respectively. An animal model was also used to confirm the two toxin levels in a…
Health-related quality of life in patients with compensated and decompensated liver cirrhosis.
2019
Compensated (Child-Pugh [CP] A) and decompensated (CP B/C) liver cirrhosis significantly differs in terms of impairment of health-related quality of life (HRQoL). However, sufficient data on potentially treatable factors associated with HRQoL in both stages of the disease are still lacking. Consequently, aims of this study were to determine differences in HRQoL between patients with compensated and decompensated liver cirrhosis and to identify potentially treatable factors associated with HRQoL.218 patients with liver cirrhosis were enrolled into this study. Chronic Liver Disease Questionnaire (CLDQ) was used to assess HRQoL. Covert hepatic encephalopathy (CHE) was diagnosed according to a …