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1.
Front Microbiol ; 11: 589405, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33363522

RESUMEN

Undergraduate microbiology curriculum should be amenable to periodic changes to incorporate new developments and ideas. The curriculum should be used not merely as a way to disseminate facts but also as a way to allow students to experience the process of science. In the context of undergraduate microbiology education in Osmania University (Hyderabad, India), existing curriculum does not explicitly allow students to engage in deeper understanding of concepts and understanding of the process of science, both in lecture and laboratory courses. The assessment methods that are currently used are limited in scope as they only test factual recall and superficial understanding of the subject and very minimally assess critical thinking skills. Another factor hampering innovation in the broader context of undergraduate education is the unavailability and inaccessibility to adequate resources. To address the issue of resource-limitations in implementing activities that expose undergraduate students to real-world microbiology experiences, a collaboration between a research institute and two teaching colleges was formed. This collaboration involved teacher and student workshops on exploring microbial diversity using 16S rRNA analysis with a view of blending novel research questions with technical skills in the undergraduate microbiology lab. This effort is an example of educators providing students with authentic experiences and, helping them gain critical knowledge and research skills in microbiology even under resource constraints, and students demonstrating motivation to participate in similar activities in the future. The collaborative effort described here can be a broadly sustainable model to improve overall undergraduate education in relatively resource-limited environments.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 233: 118189, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32120290

RESUMEN

The dielectric permittivity of propylene glycol/sulfolane binary mixtures have been determined at various temperatures in the frequency range of 0.02 ˂ν/GHz˂ 20 using open-ended coaxial probe method. The permitivity spectra of propylene glycol/sulfolane mixtures with an asymmetric shape is observed. The experimental dielectric permittivity, relaxation time values are used to obtain remaining excessive parameters such as excess permittivity (εE), deviation in refractive index (ΔnD) excess inverse relaxation time (1/τ)ε, Kirkwood effective correlation factor (geff) and active thermodynamic parameters. Redlich-Kister polynomial equation is used to fit the excessive dielectric parameters. The molecular interaction between propylene glycol and sulfolane binary mixtures is interpreted in terms of short and long-range interactions among the dipoles. The experimental dipole moment values are compared with the theoretical dipole moment values from DFT/B3LYP, MP2 methods. Natural bond orbital (NBO) analysis is performed on the optimized geometrical structure of the above system to understand molecular interaction between the binary mixtures in terms of hydrogen bonding. The chemical stability of the system is studied from the HOMO-LUMO calculations. The energy of H- bond interaction between propylene glycol and sulfolane binary mixture is calculated from the single point energy calculations, and the results are correlated.

3.
Artículo en Inglés | MEDLINE | ID: mdl-22983205

RESUMEN

Fe(3+) doped poly vinyl alcohol (PVA) capped ZnSe nanoparticles have been synthesized by using chemical method at room temperature. The prepared sample is characterized by X-ray diffraction, optical, photoluminescence (PL), electron paramagnetic resonance (EPR) and FT-IR techniques. Different physical parameters are evaluated by using measured values of refractive index and density. From the X-ray diffraction pattern, the average crystallite size is calculated by using Scherrer's formula and it is about 9 nm. Optical absorption spectrum reveals that the Fe(3+) ion enter into the lattice as octahedral symmetry. Crystal field (Dq) and inter-electronic repulsion parameters (B, C) are evaluated for Fe(3+) doped ZnSe nanoparticles as Dq=720, B=720 and C=2500 cm(-1). Photoluminescence spectrum of Fe(3+) doped ZnSe exhibits emission bands in UV and yellow regions. EPR spectrum showed various resonance signals at g=7.3, 3.5 and 2.0. FT-IR spectrum of Fe(3+) doped PVA capped ZnSe indicates the presence of O-H, C-H, C=C and C=O molecular groups.


Asunto(s)
Hierro/química , Nanopartículas/química , Alcohol Polivinílico/química , Compuestos de Selenio/química , Compuestos de Zinc/química , Cationes/química , Espectroscopía de Resonancia por Spin del Electrón , Luminiscencia , Refractometría , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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