Search results for " variability"

The effects of lasers on bond strength to ceramic materials: A systematic review and meta-analysis

2018

Lasers have recently been introduced as an alternative means of conditioning dental ceramic surfaces in order to enhance their adhesive strength to cements and other materials. The present systematic review and meta-analysis aimed to review and quantitatively analyze the available literature in order to determine which bond protocols and laser types are the most effective. A search was conducted in the Pubmed, Embase and Scopus databases for papers published up to April 2017. PRISMA guidelines for systematic review and meta-analysis were followed. Fifty-two papers were eligible for inclusion in the review. Twenty-five studies were synthesized quantitatively. Lasers were found to increase bo…

Algunos aspectos de la variabilidad de los oogonios en poblaciones actuales del género <i>Chara</i> (Charophyceae). Aplicación paleontoló…

1986

A critical revision of some useful taxonomic criteria in paleontology of Charophytes is carried Out. The results are based in four modern populations ((<i>Chara aculeolata, Chara</i> aff.<i>baltica, Chara delicatula</i> and <i>Chara globularis</i>) and they permit to make some serious objections to these critera. The results are related with three principal aspects: the meaning of the absolute magnitudes of me girogonite, the behaviour of his joint variation and the morphological variability during the calcification process. In general, and for each one of the four populations, an absence of influence of the position of the girogonite over their measureme…

Definition of response to antiviral therapy in chronic hepatitis C

2000

Sun-induced fluorescence - a new probe of photosynthesis: First maps from the imaging spectrometer HyPlant.

2015

Variations in photosynthesis still cause substantial uncertainties in predicting photosynthetic CO2 uptake rates and monitoring plant stress. Changes in actual photosynthesis that are not related to greenness of vegetation are difficult to measure by reflectance based optical remote sensing techniques. Several activities are underway to evaluate the sun-induced fluorescence signal on the ground and on a coarse spatial scale using space-borne imaging spectrometers. Intermediate-scale observations using airborne-based imaging spectroscopy, which are critical to bridge the existing gap between small-scale field studies and global observations, are still insufficient. Here we present the first …

Effects of eight weeks of physical training on physical performance and heart rate variability in children

2017

Kraama, Liisa. 2013. Effects of eight weeks physical training on physical performance and heart rate variability in children. University of Jyvaskyla, Department of Biology of Physical Activity. Master’s Thesis in Exercise Physiology. 52 pp. Physical activity and aerobic capacity have decreased among children and adolescents during the last decades. Physically active adults have been shown to have higher heart rate variability (HRV) than less active adults. In adults training-induced changes in physical performance have been shown to be related to increase in HRV, especially in high frequency component (HF), which is a marker of parasympathetic activity. The purpose of this study was to exa…

Genetic instability in calamondin (Citrus madurensis Lour.) plants derived from somatic embryogenesis induced by diphenylurea derivative

2007

Somatic embryos were regenerated in vitro from calamondin style-stigma explants cultured in the presence of N (6)-benzylaminopurine (BAP) cytokinin and three synthetic phenylurea derivatives, N-(2-chloro-4-pyridyl)-N-phenylurea (4-CPPU), N-phenyl-N'-benzothiazol-6-ylurea (PBU) and N,N'-bis-(2,3-methilendioxyphenyl)urea (2,3-MDPU). The phenylurea derivative compounds tested at micromolar level (12 muM) were able to induce a percentage of responsive explants significantly higher from that obtained with BAP and hormone-free (HF) conditions. In order to verify the genetic stability of the regenerants, 27 plants coming from different embryogenic events were randomly selected from each different …

Clinical relevance of genetic heterogeneity in HCV

2010

Infection by HCV affects an estimated 170 million people worldwide and it represents one of the major causes of liver transplantation and a heavy burden to healthcare systems. As with many other RNA viruses, HCV is characterized by very high levels of genetic variation, which have been associated to differences in disease progression and efficiency of antiviral treatment. Studies show many contradictory results and little consensus on such associations. Nevertheless, some general guidelines translating research results to clinical practice have been postulated. Here, we review the main research results obtained on HCV variation so far and explore the reasons for their lack of congruence und…

Combined approaches to identify genomic regions involved in phenotypic differentiation between low divergent breeds: Application in Sardinian sheep p…

2019

Selective breeding has led to modifications in the genome of many livestock breeds. In this study, we identified the genomic regions that may explain some of the phenotypic differences between two closely related breeds from Sardinia. A total of 44 animals, 20 Sardinian Ancestral Black (SAB) and 24 Sardinian White (SW), were genotyped using the Illumina Ovine 50K array. A total of 68, 38 and 15 significant markers were identified using the case–control genome-wide association study (GWAS), the Bayesian population differentiation analysis (FST) and the Rsb metric, respectively. Comparisons among the approaches revealed a total of 22 overlapping markers between GWAS and FST and one marker bet…

Emiliania huxleyi calcite mass variability during periods of atmospheric CO2 rising in the Mediterranean Sea

2013

The Interaction Between Physical and Psychosocial Stressors

2020

Do physical and psychosocial stressors interact to increase stress in ways not explainable by the stressors alone? A preliminary study compared participants’ stress response while subjected to a physical stressor (reduced or full physical load) and a predetermined social stressor (confronted by calm or aggressive behavior). Salivary cortisol samples measured endocrine stress. Heart rate variability (HRV) and electrodermal activity (EDA) measured autonomic stress. Perceived stress was measured via discomfort and stress state surveys. Participants with a heavier load reported increased distress and discomfort. Encountering an aggressive individual increased endocrine stress, distress levels, …