569 research outputs found
Relationship between cost of equity capital and voluntary corporate disclosures
The relationship between disclosure and cost of equity capital has always been interesting not only for managers, but for investors as well. Economic theory suggests that by increasing the level of corporate reporting firms not only increase their stock market liquidity, but they also decrease the investors’ estimation risk, arising from uncertainty about future returns and payout distributions. Utilizing the Residual Income Valuation Model, the implied cost of capital is estimated for a sample of 121 Swiss listed, non-financial companies adopting a finite horizon version of the residual income valuation model. The results show that firms on the Swiss market can reduce their cost of equity capital by increasing the level of their voluntary corporate disclosures. The results persist even after controlling for various firm specific risks, such as firm size or financial leverage and regardless of company’s reporting strategy (conservative or aggressive)
Short-term effect of non-preserved cationic oil in-water ophthalmic emulsion on tear meniscus parameters of healthy individuals in a prospective, controlled pilot study
Background: This study investigated the effect of instilling a single drop of non-preserved cationic oil-in-water ophthalmic emulsion (Cationorm®) on the lower (LTM) and upper tear meniscus (UTM) parameters of normal eyes.
Methods: In this prospective, single-center, non-randomized, controlled pilot study, optical coherence tomography was used to estimate the UTM and LTM height, depth, and cross-sectional area in participants without a history of dry eye disease. In the right eye (study eye), we instilled one drop of Cationorm® in the lower conjunctival sac. Scans of the tear menisci were acquired at baseline, before the instillation, and at 5, 15, and 30 min thereafter. Control scans of the left eye (control eye) were obtained at the same timepoints. The tear meniscus parameters of the study eye were compared with the control eye at each timepoint.
Results: Twenty subjects (11 male and 9 female; mean ± standard deviation of age: 37.8 ± 10.9 years) were included in the study. Compared to the control eye, instillation of a single drop of Cationorm® resulted in significantly higher LTM parameter values and a higher UTM cross-sectional area up to 30 min after instillation (all P < 0.05). The UTM height and depth were significantly greater in the study eye than in the control eye up to 5 min (P < 0.001 and 0.007, respectively) and 15-min (P = 0.045, and 0.002, respectively) after Cationorm® instillation. In the study eye, Cationorm® resulted in a significant increase in LTM parameter values up to 30 min post-instillation (all P < 0.001). The UTM height was significantly greater up to 15 min post-instillation than at baseline. The UTM depth and area increased significantly from baseline to 5 min after instillation (P = 0.043, and 0.002, respectively).
Conclusions: Cationorm® seems to have a prolonged residence time on the ocular surface of healthy subjects as indicated by LTM parameters and to a lesser extent by UTM parameters
Expression and Localization of Glycosaminoglycans/Proteoglycan in Pterygium: An Immunohistochemical Study
Pterygium is a triangle-shaped fibrovascular hyperplasia of the bulbar conjunctiva on the cornea. The purpose of this study was to analyze Proteoglycans (PGs) by Immunohistochemistry (IHC) in pterygium tissues and to compare the results with normal conjunctiva. Twenty-four patients (14 males) undergoing primary pterygium excision and 17 healthy individuals (10 males), undergoing extracapsular cataract surgery, were included. Pterygium tissues and normal conjunctiva tissues were surgically removed. The tissue sections were fixed in 2% paraformaldehyde and incubated with monoclonal antibodies against PGs anti-mouse IgG. Immunohistochemical study showed stronger expression of keratan sulfate in the stroma of the pterygium compared to normal conjunctiva. An increased expression of heparan sulfate was observed in the epithelial layer and around the pterygium vessels. On the other hand, dermatan sulfate showed an increased expression and localization not only in the sub-epithelial area of the pterygium and normal conjunctiva, yet throughout the stroma of the pterygium. The differences in the expression and localization of the studied extracellular matrix proteoglycans in the pterygium tissue compared to normal conjunctiva may explain the tissue hyperplasia, structure, and the functional properties in pterygium
Microbiology and atmospheric processes: Biological, physical and chemical characterization of aerosol particles
The interest in bioaerosols has traditionally been linked to health hazards for humans, animals and plants. However, several components of bioaerosols exhibit physical properties of great significance for cloud processes, such as ice nucleation and cloud condensation. To gain a better understanding of their influence on climate, it is therefore important to determine the composition, concentration, seasonal fluctuation, regional diversity and evolution of bioaerosols. In this paper, we will review briefly the existing techniques for detection, quantification, physical and chemical analysis of biological particles, attempting to bridge physical, chemical and biological methods for analysis of biological particles and integrate them with aerosol sampling techniques. We will also explore some emerging spectroscopy techniques for bulk and single-particle analysis that have potential for in-situ physical and chemical analysis. Lastly, we will outline open questions and further desired capabilities (e. g., in-situ, sensitive, both broad and selective, on-line, time-resolved, rapid, versatile, cost-effective techniques) required prior to comprehensive understanding of chemical and physical characterization of bioaerosols
An Exercise in Visualizing Colexification on a Semantic Map
This paper aims at investigating the polysemic patterns associated with the
notion ‘soil/earth’ by using the semantic map model as a methodological tool.
We focus on the applicability of the model to the lexicon, since most of past
research has been devoted to the analysis of grammatical morphemes. The most
concise result of our research is a diagrammatic visualization of the semantic
spaces of twenty lexemes in nine different languages, mainly ancient languages
belonging to the Indo-European and the Afro-Asiatic language families. The
common semantic map for the various languages reveals that the semantic spaces
covered by the investigated lexemes are often quite different from one
another, although common patterns can also be detected. Our study highlights
some shortcomings and methodological problems of previous analyses suggesting
that a possible solution to these problems is the control of the data in the
existing sources of the object languages. Finally, drawing upon the cognitive
linguistics literature on the various types of semantic change, we show that
some of the senses of the individual lexemes are the result of the function of
such mechanisms as metaphor, metonymy, and generalization
Heterogeneous ice nucleation activity of bacteria: new laboratory experiments at simulated cloud conditions
The ice nucleation activities of five different <i>Pseudomonas syringae</i>, <i>Pseudomonas viridiflava</i> and <i>Erwinia herbicola</i> bacterial species and of Snomax™ were investigated in the temperature range between &minus;5 and &minus;15&deg;C. Water suspensions of these bacteria were directly sprayed into the cloud chamber of the AIDA facility of Forschungszentrum Karlsruhe at a temperature of &minus;5.7&deg;C. At this temperature, about 1% of the Snomax™ cells induced immersion freezing of the spray droplets before the droplets evaporated in the cloud chamber. The living cells didn't induce any detectable immersion freezing in the spray droplets at &minus;5.7&deg;C. After evaporation of the spray droplets the bacterial cells remained as aerosol particles in the cloud chamber and were exposed to typical cloud formation conditions in experiments with expansion cooling to about &minus;11&deg;C. During these experiments, the bacterial cells first acted as cloud condensation nuclei to form cloud droplets. Then, only a minor fraction of the cells acted as heterogeneous ice nuclei either in the condensation or the immersion mode. The results indicate that the bacteria investigated in the present study are mainly ice active in the temperature range between &minus;7 and &minus;11&deg;C with an ice nucleation (IN) active fraction of the order of 10<sup>&minus;4</sup>. In agreement to previous literature results, the ice nucleation efficiency of Snomax™ cells was much larger with an IN active fraction of 0.2 at temperatures around &minus;8&deg;C
Testing Currency Predictability Using An Evolutionary Neural Network Model
Two alternative learning approaches of a MLP Neural Network architecture are employed to forecast foreign currencies against the Greek Drachma, a Back-Propagation with a hyperbolic tangent activation scheme and an evolutionary trained model. Four major currency data series, namely the U. S. Dollar, the British Pound, the French Franc and the Deutsche Mark, are used in this forecasting experiment. Extended simulations have shown a high predictive ability, which is significantly better when using the actual rates compared to using the logarithmic returns of each series. The genetic algorithm performs best on FF and DM, while the back-propagation on USD and BP
Bacteriology and Antimicrobial Susceptibility Patterns of Childhood Acute Bacterial Conjunctivitis in Western Greece
Acute bacterial conjunctivitis is a common, highly contagious infection in children and is usually treated empirically with broad spectrum topical antibiotics. In the current study we investigated bacteriology and antibiotic susceptibility patterns in childhood acute bacterial conjunctivitis in Western Greece. We conducted a retrospective analysis of presumed acute bacterial conjunctivitis cases in ''Karamandaneio'' Pediatric General Hospital of Patras, Western Greece, between February 1, 2013 and January 31, 2018. Specimens from the lower conjunctiva fornix were isolated from 191 cases and outcomes were analyzed to identify the pathogenic bacteria of acute bacterial conjunctivitis and their corresponding antibiotic susceptibility patterns. Patients were divided into 3 groups; Group A included neonates under 28 days of life, Group B children from 1 month to 2 years and Group C from 2 years to 14 years. Results revealed that Staphylococcus spp., Haemophilus spp. and Streptococcus spp. were the most prevalent pathogens. No significant differences in isolated pathogens were found between the age groups. Antibiotic resistance rates were higher against ampicillin, ceftriaxone, ceftazidime and sulfamethoxazole. Resistance rates to Ciprofloxacin were low while none of the evaluated isolates were resistant to vancomycin. We concluded that predominant pathogens of childhood acute bacterial conjunctivitis in Western Greece were Staphylococcus spp., Haemophilus spp. and Streptococcus spp. Continuous surveillance, focused in distinct geographic areas, is encouraged to prepare more precise protocols of empirical treatment. Epub: October 1, 2019
Modeling And Forecasting Exchange-Rate Shocks
This paper considers the extent to which the application of neural networks methodology can be used in order to forecast exchange-rate shocks. Four major foreign currency exchange rates against the Greek Drachma as well as the overnight interest rate in the Greek market are employed in an attempt to predict the extent to which the local currency may be suffering an attack. The forecasting is extended to the estimation of future exchange rates and interest rates. The MLP proved to be highly successful in predicting the shocks, while exhange-rates and interest-rates forecasts with MLP and RBF optimized by a genetic algorithm resulted in good approximations
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