Search results for "index"
showing 10 items of 5395 documents
A note on boundary conditions for nonlinear operators
2008
We investigate boundary conditions for strict-$\psi$-contractive and $\psi$-condensing operators. We derive results on the existence of eigenvectors with positive and negative eigenvalues and we obtain fixed point theorems for classes of noncompact opera\-tors.
Development of core-shell colloids to study self-diffusion in highly concentrated dispersions
2007
To study single particle motion in highly concentrated colloidal dispersions, a host-tracer colloid system was developed, consisting of crosslinked polymer micronetwork spheres placed in a good solvent. The host colloid is made invisible to the experimental probe by matching its refractive index to that of the solvent. For the tracer particles a core-shell structure was chosen to ensure the interaction potential to be identical to that of the host particles. Therefore the shell was made of the same polymer as the host. The core differs in refractive index from the solvent and is therefore visible due to scattered light.
On a topological interpretation of electronic and vibrational molecular energies
1998
Abstract A relationship between Randic's connectivity index and various quantum mechanical parameters derived from the Huckel Molecular Orbital (HMO) approach is demonstrated. When applied to conjugated hydrocarbons, this index represents the measure of the global π electron molecular energy and, therefore, of the resonance energy. Moreover, the development of the procedure, allows the introduction of a new definition of the bond order which, in turn, makes possible a better prediction not only for bond lengths of naphtalene but also for the resonance integral and conjugation energy for butadiene. Also, a corrected value for the Randic index is deduced, which allows for the reduction of the…
Lateral magnification matrix from the dioptric power matrix formalism in the paraxial case.
2012
Background Previous studies have highlighted that power matrices fully characterize the concept of dioptric power of any astigmatic surface. Thus, the basic equations in physiological optics can be generalized using the matrix formalism of the dioptric power. Among others, lateral magnification has also been interpreted as a matrix but mainly concerning magnification modification induced by spectacle correction of refractive error. Purpose To provide a fresh look into a novel paraxial formulation for the assessment of the lateral magnification using power matrices and in presence of astigmatism for thin and thick imaging systems in general. Methods Linear optics provides the frame to genera…
Unconventional Reducing Gases Monitoring in Everyday Places
2017
Abstract Air pollution, be it indoors or outdoors, is a major environmental health concern as it can lead to serious health effects, such as respiratory diseases, including asthma and lung cancer. Much progress has been made in Europe in improving outdoor air quality and limit values have been set for several pollutants. However, indoor air quality also requires attention because this is where we spend most of our time. Measurements at appropriate spatial and temporal scales are essential for understanding and monitoring heterogeneous environments with complex and highly variable emission sources, such as in urban areas. However, the costs and complexity of conventional air quality measurem…
Comparison of Crop Trait Retrieval Strategies Using UAV-Based VNIR Hyperspectral Imaging.
2021
Hyperspectral cameras onboard unmanned aerial vehicles (UAVs) have recently emerged for monitoring crop traits at the sub-field scale. Different physical, statistical, and hybrid methods for crop trait retrieval have been developed. However, spectra collected from UAVs can be confounded by various issues, including illumination variation throughout the crop growing season, the effect of which on the retrieval performance is not well understood at present. In this study, four retrieval methods are compared, in terms of retrieving the leaf area index (LAI), fractional vegetation cover (fCover), and canopy chlorophyll content (CCC) of potato plants over an agricultural field for six dates duri…
Semaglutide reduces fat accumulation in the tongue: A randomized single-blind, pilot study
2021
Abstract Aim We evaluated the effect of the latest GLP-1 RA semaglutide on tongue fat storage in obese women. Design. We conducted a randomized single-blind, pilot study. Methods Twenty-five obese women with polycystic ovary syndrome (PCOS) (33.7 ± 5.3 years, body mass index (BMI) 36.1 ± 3.9 kg/m2, mean ± SD) were randomized to semaglutide 1.0 mg or placebo for 16 weeks. We quantified tongue volume and its fat tissue and fat proportion by magnetic resonance imaging. Results Tongue fat tissue and fat proportion significantly reduced after semaglutide vs placebo (-1.94 ± 5.51 vs. + 3.12 ± 4.87 cm3, p = 0.022, and −0.02 ± 0.07 vs. 0.04 ± 0.06, p = 0.010, respectively). Correlation analysis rev…
Body mass index as a predictor of all-cause mortality in nursing home residents during a 5-year follow-up.
2013
Background: Body mass index (BMI) is considered a short-term mortality predictor, but a consensus has not been reached on its role and that of other nutritional parameters in predicting long-term mortality in nursing home residents. Objectives: To correlate BMI, Mini Nutritional Assessment scores, and serum albumin levels with the 5-year mortality rate in institutionalized elderly subjects. Methods: A total of 181 nursing home residents aged ≥70 years were included in a 5-year longitudinal study. Data were collected on all participants' nutritional, health, cognitive, and functional status by means of a comprehensive geriatric assessment. Data on the participants' vital status were obtained…
Functional diversity of decomposer organisms in relation to primary production
1998
Abstract The term `biodiversity' is claimed to lack connections to a serious scientific background. In this work, we approached the concept of biodiversity from a functional point of view by asking: “At what level of the ecological organization (species, trophic species/feeding guilds, trophic levels etc.) should reduction in biodiversity matter to bring about visible changes in ecosystem performance?” We investigate the concepts of `functional diversity' and `ecosystem performance' in relation to feeding habits (such as fungivory, detritivory etc.) of soil fauna and plant growth. After analysing the results of a number of microcosm studies, we came into the following conclusions: (i) troph…
SARS-CoV-2 antibodies, serum inflammatory biomarkers and clinical severity of hospitalized COVID-19 patients
2020
Background The involvement of SARS-CoV-2 antibodies in mediating immunopathogenetic events in COVID-19 patients has been suggested. By using several experimental approaches, we investigated the potential association between SARS-CoV-2 IgGs recognizing the spike (S) protein receptor-binding domain (RBD), neutralizing antibodies (NtAb) targeting S, and COVID-19 severity. Patients and methods This unicenter, retrospective, observational study included 51 hospitalized patients (24 at the intensive care unit; ICU). A total of 93 sera from these patients collected at different time points from the onset of symptoms were analyzed. SARS-CoV-2 RBD IgGs were quantitated by ELISA and NtAb50 titers wer…