Invariance: a Theoretical Approach for Coding Sets of Words Modulo Literal (Anti)Morphisms

Let $A$ be a finite or countable alphabet and let $\theta$ be literal (anti)morphism onto $A^*$ (by definition, such a correspondence is determinated by a permutation of the alphabet). This paper deals with sets which are invariant under $\theta$ ($\theta$-invariant for short).We establish an extension of the famous defect theorem. Moreover, we prove that for the so-called thin $\theta$-invariant codes, maximality and completeness are two equivalent notions. We prove that a similar property holds in the framework of some special families of $\theta$-invariant codes such as prefix (bifix) codes, codes with a finite deciphering delay, uniformly synchronized codes and circular codes. For a special class of involutive antimorphisms, we prove that any regular $\theta$-invariant code may be embedded into a complete one.Comment: To appear in Acts of WORDS 201

The interaction of nanoparticles with mucosal barriers

PhD ThesisThe aim of this thesis was to assess the safety profile of different novel nanoparticles when interacting with lung bronchial epithelial cells in vitro, especially their role in inflammation and cytotoxicity. In addition, the permeation behaviour of self-nanoemulsifying drug delivery systems (SNEDDS) was measured by a novel mucus diffusion model utilizing standardized transwell diffusion plates. Methods: Primary bronchial epithelial and Calu-3 cells were cultured in 24 and 96 well plates. Different formulations of nanoparticles (NPs) were used to measure IL-8 production by cells as a marker of inflammation (measured by sandwich ELISA). The Celltitre blue (CTB) and MTT assays were used to test cell viability. The effect of cell density on the CTB assay was studied (500k, 400k, 300k, 200k, 100k, 50k, 42k, 33k, 25k, 17k, and 8.3k) in 24 well plates. Permeation studies were examined by using a mucus diffusion model. The rheology of the mucus was investigated to evaluate the gel structure of the mucus. Results: The viability of cell exposed to 52nm polystyrene NPs showed no statistical difference between cells with NPs and cells without NPs after 24 hour of exposure. The nanoparticles were shown to interfere with both the CTB and MTT assays. The standard curves in the CTB assay vary as the cell density decreased. Although IL-8 was shown to be slightly increased in human primary cells after exposure to different concentrations of NPs, IL-8 increased significantly after exposures to the same proportion of sterile water as these nanoparticles were delivered in (a control for osmolarity). The composition of SNEDDS might play a major role in their capacity to permeate the mucus such as lauroglycol. The small intestine mucus gels have some degree of frequency dependency; between 0.1 and 1 Hz, there was a decline in both iv G` and Gʺ followed by a rise over 1-10Hz. Gʺ increased relative to G` suggesting a tendency to flow. This change at high frequency is verified by an increase in the phase angle, demonstrating a weaker gel. This biphasic behaviour may be explained by the gel forming interactions having time to break and make at a low frequency but at a high frequency, they do not have time to reform. Conclusion: I have found that both CTB and MTT assays may not be sensitive enough to test viability of cells exposed to nanoparticles. Therefore, other assay systems are required to test these NPs with respect to cytotoxicity. The composition of the SNEDDS played an important role in determining the permeation of the mucus gel layer

Theoretical and experimental studies on torque converters

Lysholm-Smith torques converters has a special importance, due to the fact that this kind of machine can realize a continuously variation of the torque and of the rotational speed to the outlet shaft as function of the resistant torqueand, in the same time, an amortization of the shocks and vibrations. This type of torque converter has three turbine stages, intercalated by two stages of reactors (having stationary blades). The present paper presents theoretical and experimental results obtained on a Lysholm-Smith torque converter CHC-380 in the laboratory of Hydraulic Machinery Departmentfrom POLITEHNICA University of Timişoara, ROMÂNIA. Theoretical, was studied the behavior of the torque converter, expressed by the characteristic curves. Experimentally, was studied the variation of the temperature inside the torque converter with and without the cooling system and, also, the influence of the filling degree on the characteristic curves. The paper discusses, in the same time the definition and the variation of the degree of transparency for this particular torque converter

Solution-processed bilayer photovoltaic devices with nematic liquid crystals

The cross-linking of polymerisable liquid crystalline semiconductors is a promising approach to solution-processable, multilayer, organic photovoltaics. Here we demonstrate an organic bilayer photovoltaic with an insoluble electron-donating layer formed by cross-linking a nematic reactive mesogen. We investigate a range of perylene diimide (PDI) materials, some of which are liquid crystalline, as the overlying electron acceptor layer. We find that carrier mobility of the acceptor materials is enhanced by liquid crystallinity and that mobility limits the performance of photovoltaic devices. © 2013 © 2013 Taylor & Francis

Reaction Dynamics for the Systems 7Be,8B + 208Pb at Coulomb Barrier Energies

In this contribution we describe the first results obtained for the investigation of the elastic scattering process in the reactions induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at Coulomb barrier energies. The experimental data were analyzed within the framework of the optical model in order to extract the total reaction cross section. The comparison with data available in literature for reactions induced on 208Pb by light ions in the mass range A = 6-8 shows that the loosely-bound 8B has the largest reactivity

Nanofibers

Cellulose is the most available biopolymer on earth existent in wood and other lignocellulosic sources, which can be isolated as nanofibers to reinforce composites. The aim of this chapter overview was to explain cellulose nanofibers’ preparation methods from different plant sources. The chemical treatment of cellulose fibers including dilute alkali swelling, acid and base hydrolysis, and bleaching was carried out followed by a mechanical method to isolate nanofibers. In this study, the effect of few palnt source variations and mechanical processes used in extraction procedure on nanofibers morphology, crystallinity, and chemical composition was evaluated. Characteristics of extracted cellulose nanofibers obtained from different plant sources were presented as well

Pheochromocytoma – clinical manifestations, diagnosis and current perioperative management

Pheochromocytoma is a neuroendocrine tumor characterized by the excessive production of catecholamines (epinephrine, norepinephrine, and dopamine). The diagnosis is suspected due to hypertensive paroxysms, associated with vegetative phenomena, due to the catecholaminergic hypersecretion. Diagnosis involves biochemical tests that reveal elevated levels of catecholamine metabolites (metanephrine and normetanephrine). Functional imaging, such as 123I-metaiodobenzylguanidine scintigraphy (123I-MIBG), has increased specificity in identifying the catecholamine-producing tumor and its metastases. The gold-standard treatment for patients with pheochromocytoma is represented by the surgical removal of the tumor. Before surgical resection, it is important to optimize blood pressure and intravascular volume in order to avoid negative hemodynamic events

On the ability of perfluorohexane sulfonate (PFHxS) bioaccumulation by two Pseudomonas sp. strains isolated from PFAS‐contaminated environmental matrices

PFASs (perfluoroalkyl and polyfluoroalkyl substances) are highly fluorinated, aliphatic, synthetic compounds with high thermal and chemical stability as well as unique amphiphilic properties which make them ingredients in a range of industrial processes. PFASs have attracted consideration due to their persistence, toxicity and bioaccumulation tendency in the environment. Recently, attention has begun to be addressed to shorter‐chain PFASs, such as perfluorohexane sulfonate [PFHxS], apparently less toxic to and more easily eliminated from lab animals. However, short‐chain PFASs represent end‐products from the transformation of fluorotelomers whose biotic breakdown reactions have not been identified to date. This means that such emergent pollutants will tend to accumulate and persist in ecosystems. Since we are just learning about the interaction between short‐chain PFASs and microorganisms, this study reports on the response to PFHxS of two Pseudomonas sp. strains isolated from environmental matrices contaminated by PFASs. The PFHxS bioaccumulation potential of these strains was unveiled by exploiting different physiological conditions as either axenic or mixed cultures under alkanothrofic settings. Moreover, electron microscopy revealed nonorthodox features of the bacterial cells, as a consequence of the stress caused by both organic solvents and PFHxS in the culturing substrate