Wrocław University of Technology

About: Wrocław University of Technology is a education organization based out in Wrocław, Poland. It is known for research contribution in the topics: Laser & Fuzzy logic. The organization has 13115 authors who have published 31279 publications receiving 338694 citations.

Third-Order Nonlinear Optical Properties of Colloidal Gold Nanorods

Abstract: We have evaluated the third-order nonlinear optical properties of gold nanorods in water solution in a broad range of wavelengths including both the longitudinal and transverse surface plasmon resonance (SPR) bands. On the basis of the analysis of Z-scan measurements performed with femtosecond laser pulses, we conclude that the optical nonlinearity in the longitudinal-SPR absorption range originates mainly from the saturation of the one-photon absorption, whereas a resonant two-photon absorption process is dominant in the transverse-SPR range of wavelengths. The discrepancies in the values of two-photon absorption coefficients reported by various researchers and the methods of reliable comparison of the results are discussed.

Adsorption Kinetics of Ultrathin Polymer Films in the Melt Probed by Dielectric Spectroscopy and Second-Harmonic Generation

Abstract: We studied the adsorption kinetics of supported ultrathin films of dye-labeled polystyrene (l-PS) by combining dielectric spectroscopy (DS) and the interface-specific nonlinear optical second harmonic generation (SHG) technique. While DS is sensitive to the fraction of mobile dye moieties (chromophores), the SHG signal probes their anisotropic orientation. Time-resolved measurements were performed above the glass transition temperature on two different sample geometries. In one configuration, the l-PS layer is placed in contact with the aluminum surface, while in the other one, the deposition is done on a strongly adsorbed layer of neat PS. From the time dependence of the dielectric strength and SHG signal of the l-PS layer in contact with the metal, we detected two different kinetics regimes. We interpret these regimes in terms of the interplay between adsorption and orientation of the adsorbing labeling moieties. At early times, dye moieties get adsorbed adopting an orientation parallel to the surface. When adsorption proceeds to completeness, the kinetics slows down and the dye moieties progressively orient normal to the surface. Conversely, when the layer of l-PS layer is deposited on the strongly adsorbed layer of neat PS, both the dielectric strength and the SHG signal do not show any variation with time. This means that no adsorption takes place.

Nutritional significance of amino acids, vitamins and minerals as nutraceuticals in poultry production and health – a comprehensive review

Abstract: Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals' normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.

Improving the Performance of Sentiment Analysis of Tweets Containing Fuzzy Sentiment Using the Feature Ensemble Model

Abstract: The increase in the volume of user-generated content on Twitter has resulted in tweet sentiment analysis becoming an essential tool for the extraction of information about Twitter users' emotional state. Consequently, there has been a rapid growth of tweet sentiment analysis in the area of natural language processing. Tweet sentiment analysis is increasingly applied in many areas, such as decision support systems and recommendation systems. Therefore, improving the accuracy of tweet sentiment analysis has become practical and an area of interest for many researchers. Many approaches have tried to improve the performance of tweet sentiment analysis methods by using the feature ensemble method. However, most of the previous methods attempted to model the syntactic information of words without considering the sentiment context of these words. Besides, the positioning of words and the impact of phrases containing fuzzy sentiment have not been mentioned in many studies. This study proposed a new approach based on a feature ensemble model related to tweets containing fuzzy sentiment by taking into account elements such as lexical, word-type, semantic, position, and sentiment polarity of words. The proposed method has been experimented on with real data, and the result proves effective in improving the performance of tweet sentiment analysis in terms of the $F_{1}$ score.

A role of GABA analogues in the treatment of neurological diseases.

Abstract: gamma-Amino butyric acid is an extremely important inhibitory neurotransmitter in the mammalian central nervous system and is essential for the overall balance between neuronal excitation and inhibition. It is well documented that GABA deficiency is associated with several important neurological disorders such as Huntington's chorea, Parkinson's and Alzheimer's disease and other psychiatric disorders, like anxiety, depression, pain, panic, or mania. Although, it is known that increasing the brain concentration of GABA prevents convulsions, the high polarity and flexible structure of this compound are probably responsible for its inefficiency as an anticonvulsant when administered orally or intravenously. To resolve this problem, GABA analogues are being designed. Over recent years, there has been increasing interest in the synthesis and pharmacological effect of new GABA derivatives, which can be considered as potent drugs in the treatment of neurodegenerative disorders.