Immobilization of Trichosporon cutaneum R 57 Cells onto Methylcellulose/SiO2 Hybrids and Biosorption of Cadmium and Copper Ions

Methylcellulose/Silica (MC/SiO2) hybrids were synthesized via poly step sol-gel method. SiO2 was included into the hybrids from two silica precursors - methyltriethoxysilane (MTES) and ethyltrimethoxysilane (ETMS) with different quantity of organic part-5, 20 and 50 wt.%. The filamentous yeasts Trichosporon cutaneum strain R 57 was immobilized onto the synthesized MC/SiO2 hybrids. After immobilization the hybrid materials were used in the processes of sorption of cadmium and copper ions. The obtained results of protein content analysis indicated that the amount of protein increased with increasing of MC in the hybrids. It was established that the maximal efficiency of copper and cadmium removal were observed for hybrid materials containing MTES and 50 wt.% MC - 66% and 26% respectively. For ETMS and 50 wt.% MC a high value of copper removal was 56% and for cadmium - 45% removal, respectively. FTIR analysis of free and immobilized cells with metal ions was conducted. SEM images showed successful immobilization of the yeasts cells. Second order model was employed in order to investigate the kinetics of copper and cadmium biosorption

Staggering behavior of the low lying excited states of even-even nuclei in a Sp(4,R) classification scheme

We implement a high order discrete derivative analysis of the low lying collective energies of even-even nuclei with respect to the total number of valence nucleon pairs N in the framework of F- spin multiplets appearing in a symplectic sp(4,R) classification scheme. We find that for the nuclei of any given F- multiplet the respective experimental energies exhibit a Delta N=2 staggering behavior and for the nuclei of two united neighboring F- multiplets well pronounced Delta N=1 staggering patterns are observed. Those effects have been reproduced successfully through a generalized sp(4,R) model energy expression and explained in terms of the step-like changes in collective modes within the F- multiplets and the alternation of the F-spin projection in the united neighboring multiplets. On this basis we suggest that the observed Delta N=2 and Delta N=1 staggering effects carry detailed information about the respective systematic manifestation of both high order alpha - particle like quartetting of nucleons and proton (neutron) pairing interaction in nuclei.PACS number(s):21.10.Re, 21.60.FwComment: 22 pages and 6 figures changes in the figure caption

Born-Infeld black holes coupled to a massive scalar field

Born-Infeld black holes in the Scalar-Tensor Theories of Gravity, in the case of massless scalar field, have been recently obtained. The aim of the current paper is to study the effect from the inclusion of a potential for the scalar field in the theory, through a combination of analytical techniques and numerical methods. The black holes coupled to a massive scalar field have richer causal structure in comparison to the massless scalar field case. In the latter case, the black holes may have a second, inner horizon. The presence of potential for the scalar field allows the existence of extremal black holes for certain values of the mass of the scalar field and the magnetic (electric) charge of the black hole. The linear stability against spherically symmetric perturbations is studied. Arguments in favor of the general stability of the solutions coming from the application of the "turning point" method are also presented.Comment: 26 pages, 16 figure

A comparative study of mental health of medical students in two countries

Results from many studies indicate that throughout medical education students experience high levels of stress and depression. The aim of the current study was to assess and compare Bulgarian and Turkish medical students' levels of stress and depression. A cross-sectional study was conducted with 546 students (276 foreign students from Medical University – Sofia and 270 medical students from several medical universities in Ankara). The study instrument included basic socio-demographic questions, Medical Student Stressor Questionnaire (MSSQ-40 items) and Beck Depression Inventory (BDI). Turkish medical students showed higher levels of stress and depression than foreign students from Bulgaria. We found that all types of stressors in medical students had a relationship with depression. Results of our study imply that medical students need access to psychological support throughout their education

q-Analogue of Am−1⊕An−1⊂Amn−1A_{m-1}\oplus A_{n-1}\subset A_{mn-1}

A natural embedding $A_{m-1}\oplus A_{n-1}\subset A_{mn-1}$ for the corresponding quantum algebras is constructed through the appropriate comultiplication on the generators of each of the $A_{m-1}$ and $A_{n-1}$ algebras. The above embedding is proved in their $q$-boson realization by means of the isomorphism between the $\mathcal{A}_q^{-}$ (mn)$\sim {\otimes} ^n \mathcal{A}_q^{-}$(m)$\sim {\otimes}^m\mathcal{A}_q^{-}$(n) algebras.Comment: 11 pages, no figures. In memory of professor R. P. Rousse

Spectral and polarization effects in deterministically nonperiodic multilayers containing optically anisotropic and gyrotropic materials

Influence of material anisotropy and gyrotropy on optical properties of fractal multilayer nanostructures is theoretically investigated. Gyrotropy is found to uniformly rotate the output polarization for bi-isotropic multilayers of arbitrary geometrical structure without any changes in transmission spectra. When introduced in a polarization splitter based on a birefringent fractal multilayer, isotropic gyrotropy is found to resonantly alter output polarizations without shifting of transmission peak frequencies. The design of frequency-selective absorptionless polarizers for polarization-sensitive integrated optics is outlined

Nutrigenomics: DNA-based individualized nutrition

In the past decade, nutrition research has undergone an important shift from epidemiology and physiology to molecular biology, adipobiology and genetics, thus launching the science of nutrigenomics. To at molecular level study effects of nutrition on health and disease. The completion of several large genome projects has markedly altered the research agenda by drawing attention to the importance of genes in human nutrition. There has been a growing recognition that micronutrients and macronutrients can be potent dietary signals that influencethemetabolic pathways of cells and have an important role in the control of energy, vascular and neuronal homeostasis. Accordingly, nutrition researchers have increasingly started to recognize that gene-environment interactions can be implicated in the pathogenesis of lifestyle-related diseases, particularly cardiometabolic diseases, fatty liver diseases, cancers, and Alzheimer's disease. An adiponutrigenomic insight into life expectancy is also outlined. Overall, the present Dance Round focuses on a mater of nationwide importance for Bulgaria, a country at the epicenter of today's global healthquake, the obesity and related diseases.Biomedical Reviews 2006; 17: 117-122

Developing lab activities for an introductory anatomy course: Reflections and recommendations from a faculty/student partnership.

Students “as partners” challenges the notion that students simply consume knowledge, but rather, they are viewed as co-producers of knowledge (Green, 2019). This approach used in curriculum development is illustrated in this research project. Five undergraduate students and one graduate student collaborated with a faculty member to develop ten lab activities for a first-year anatomy course in Kinesiology. All student partners had taken the course previously and had expressed their passion for the subject matter. With guidance and support from the course instructor, students utilized the knowledge and experiences they had acquired in the course to design lab experiences that aligned with the course content. This approach is consistent with other studies in which students worked with faculty members to adapt curriculum for future students (Spencer et al., 2021). Once the lab activities were created, the students were asked to reflect upon their experience. The instructor encouraged the discussion of various elements in the reflections, such as how the students felt working in the partnership, and their discoveries related to curriculum development. The students were also asked to consider the impact of the partnership on both their well-being and on higher education in general. The analysis revealed seven themes which will be shared in the presentation. Several recommendations, including the importance of maintaining effective communication, fostering group cohesion, and developing a knowledge transfer plan, will also be offered to help inform other students and faculty members who wish to engage in a similarly effective partnership. Bibliography: Green, W. (2019). Engaging “Students as Partners” in global learning: Some possibilities and provocations. Journal of Studies in International Education, 23(1), 10–29. https://doi.org/10.1177/1028315318814266 Spencer, B., Tori, K., & Campbell, R. (2021). Undergraduates as course creators: Reflections on starting and sustaining a student-faculty partnership. International Journal for Students as Partners, 5(1), 138-145. https://doi.org/10.15173/ijsap.v5i1.439