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Assessment of the phenotypic effects of Platelet Rich Fibrin on Mesenchymal Stem Cells derived from Minced Pulp
Our aim is to investigate the effects of autologous platelet-rich fibrin (PRF) on Mesenchymal Stem cell derived from Minced Pulp (MP-MSCs). We first developed a mouse model of PRF to study the phenotypic effects of PRF in cultured cells. We obtained PRF from the blood and prepared PRF-enriched culture media. The phenotypic effects of PRF on MP-MSCs were determined by assessing the changes in cell proliferation, differentiation and immunophenotypic profiling. The mRNA levels of ALP, OCN, DMP1 and DSPP were determined by qRT-PCR. It was found that PRF increased the proliferation capacity of MP-MSCs and reduced the cell doubling time. With PRF exposure, the MP-MSCs were able to retain their immunophenotypic characteristics defining them as MSCs, as the cells expressing surface markers CD105, CD146 and CD73 were higher. MP-MSCs were able to undergo osteogenic differentiation in the presence of PRF and the mRNA levels of OCN was significantly increased in the presence of PRF. To assess the odontogenic differentiation of cells in response to PRF, we prepared dentin-slice model in which we cultured MP-MSCs embedded in PRF. Histological sections of the dentin slice model revealed that there was increase in the cellularity of the pulp tissue along the edges of the pulp tissue. Based on our findings, PRF can act as a source of growth factors cell proliferation, migration and differentiation
A Symbolic Music Transformer for Real-Time Expressive Performance and Improvisation
With the widespread proliferation of AI technology, deep architectures — many of which are based on neural networks — have been incredibly successful in a variety of different research areas and applications. Within the relatively new domain of Music Information Retrieval (MIR), deep neural networks have also been successful for a variety of tasks, including tempo estimation, beat detection, genre classification, and more. Drawing inspiration from projects like George E. Lewis\u27s Voyager and Al Biles\u27s GenJam, two pioneering endeavors in human-computer interaction, this project attempts to tackle the problem of expressive music generation and seeks to create a Symbolic Music Transformer as a real-time musical improvisation companion, exploring the potential of AI to enhance the human experience of music. We successfully manage to implement the first iteration of a Transformer that can generate musical output. While the model struggles to generalize to a variety of inputs — likely due to limited training resources and data used while training — it can learn the structure of encoded midi-sequences and can generate expressive MIDI performances. We also present a working prototype of a performance environment built with Max/MSP which can parse auditory information in real-time and serve as the interface between the model and the musician.Senior Project submitted to The Division of Science, Mathematics and Computing of Bard College
Manipulating polarized light with a planar slab of Black Phosphorus
Wave polarization contains valuable information for electromagnetic signal
processing and the ability to manipulate it can be extremely useful in photonic
devices. In this work, we propose designs comprised of one of the emerging and
interesting two-dimensional media: Black Phosphorus. Due to substantial
in-plane anisotropy, a single slab of Black Phosphorus can be very efficient
for manipulating the polarization state of electromagnetic waves. We
investigate Black Phosphorus slabs that filter the fields along one direction,
or polarization axis rotation, or convert linear polarization to circular.
These slabs can be employed as components in numerous mid-IR integrated
devices
EFFECT OF SILICA NANOCONFINEMENT OF LIPID BILAYERS ON ITS PHASE TRANSITION AND ON THE COLLOIDAL STABILITY OF SILICA NANOPARTICLES
In this work, we incorporated 4-(N-Boc-aminometyl) phenylboronic acid (BA), at different concentrations, into 1,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC) bilayers confined within nanopores of two different mean pore diameters of 7.4 nm and 11.7 nm of micron sized silica particles. The confinement of DPPC into nanopores resulted in the depression in the main phase transition temperatures compared to the liposomal system. The addition of BA was found to induce disruptions in the acyl chains of the lipid molecules at all concentrations of the solute. The lipid bilayer cooperativity was found to be higher in the confined systems compared to the liposomal systems despite the presence of higher disorder in the hydrophobic acyl chains in the former as suggested by lower main phase transition temperatures. The partition coefficient of BA within the bilayers of DPPC was found to be higher in liposomal systems in comparison to the confined systems. The differences in mean pore sizes of the micron sized silica did not result in any significant differences in the partitioning behaviour of BA within DPPC. The results helped us understand the partitioning of BA in systems in which DPPC was confined into silica nanopores relative to DPPC liposomes. The knowledge of the behaviour of boronic acid in confined systems can help us in designing biomimetic systems, with optimum concentrations of the embedded molecule, to serve the purpose of separation of compounds from dilute aqueous solutions.
Subsequently, the method of evaporation deposition was used to fill the pores of silica nanoparticles with 1,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC) and assess the effect of increasing the mass ratio of lipid to silica nanoparticles on the zeta potential and colloidal stability of the nanoparticles. An increase in the mass ratio resulted in observable reductions in magnitudes of zeta potential of the resulting nanoparticles compared to bare silica nanoparticles. Lipid enveloping of pore filled silica nanoparticles results in zeta potentials comparable to that of DPPC liposomes. The reductions in zeta potentials of the lipid filled silica nanoparticles were hypothesized to be the result of several isolated lipid bilayers covering the exterior surface of the nanoparticles, besides filling the nanopores. The complete assessment of colloidal stability of the system necessitates obtaining of information regarding the changes in hydrodynamic diameters and the settling behaviour, with extended time periods, of the lipid filled particles in conjunction with the obtained values of zeta potential of the system. The determination of the optimal amount of lipids that can be deposited into the silica nanopores would enable the designing of systems involving extraction and sensing of highly lipophilic molecules from dilute solutions
The role of electrical noise in screening transformers prone to failure
Insulation used as a barrier between the high voltage and low voltage windings of a transformer has sites of in- homogeneities like pinholes, cracks or voids, developed during the manufacturing process. Thus, these minute air pockets are stressed much more than the solid dielectric, on the application of a voltage stress, because the dielectric constant of the solid insulation is many times that of the air dielectric. As a result, excitation or ionization takes place in the air (gases). The amount of excited or ionized molecules is proportional to the volume of the inhomogenei- ties within the insulation.
Therefore, experiments were conducted to monitor the electrical noise generated due to partial ionization of the tiny air gaps in the insulation. This was done by placing the transformer in a plexiglas tubing, around which an antenna was wound. The antenna was connected to a highly sensitive Hammerlund receiver, whose carrier level meter was calibrated in S-units. For 5S units of noise to be generated, the voltage stress required to be applied to the insulation was measured for a sample of three hundred transformers.
The voltage readings were analyzed statistically and were found to have a normal distribution.
Seven units which gave high voltage readings and seven units which gave low voltage. readings were subjected to accelerated life tests. This data has been analyzed statistically and has been found to be significant. The coefficient of correlation has been found and a linear regression equation has been formulated. The F-test of significance has been applied to the regression equation and has been found to be statistically significant
Effect of epidural analgesia on the duration of labour and pains: a comparative study
Background: Epidural analgesia is regional anaesthesia that blocks pain in a particular region of the body. The use of Epidural Analgesia (EA) in labor is widespread in modern labor ward practice, and its benefits in terms of pain relief are well-recognized. Objective of this study was to study the effect of epidural analgesia on the duration of labour and pains.Methods: The present study was conducted on 60 women in the department of obstetrics and gynecology at Topiwala National Medical College, Mumbai during a period from October 2014 to January 2017. The women requesting EA were assigned as the study group (Group A - 30 cases) and women not receiving EA were included in the control group (Group B - 30 cases).Results: The duration of active phase of first and second stage of labour was found to be prolonged in patients who received EA as compared to control group. An increase in number of caesarean sections and requirement of oxytocin augmentation was found to be more in Group A as compared to Group B. There was no statistically significant difference in Apgar score of newborns at 1 min and 5 min in both the groups. The patients demanding epidural drug had better pain relief during labour. In Group A, 17% of patients and in Group B, 7% of patients had nausea and vomiting. Other side effects were minimal.Conclusions: Epidural analgesia is not a totally free of disadvantages, it is the most effective mode of pain relief available compared with other techniques. The addition of patient-controlled epidural analgesia and innovations using new technologies enhance patient satisfaction
Distribution and Seasonal Abundance of Macro Benthos of Gangavali Estuary, Uttar Kannada, West Coast of India
Distribution and seasonal abundance of Gangavali estuary was studied for one year from September 2007 to August 2008. The diversity, abundance and biomass of macro-benthos were observed selecting four stations along the Gangavali estuary and eleven benthic organisms were encountered in the present study. Polycheates were observed at all four stations with maximum faunal distribution. The diversity of macro benthos was at maximum numbers towards lower reaches of the estuary. The benthic faunal components exhibit bimodal pattern of distribution with monsoon as a period of minimum density and post-monsoon and early pre-mansion with maximum density
Explaining foreign firms' approaches to corporate political activity in emerging economies: the effects of resource criticality, product diversification, inter-subsidiary integration, and business ties
Despite the increasing scope for transactional approaches to corporate political activity (CPA) in emerging markets and rising concerns about the use of relational approaches, foreign firms in emerging economies appear to be reluctant to adopt transactional approaches to CPA. Using Resource Dependence theory we argue that criticality of resources, product diversification, integration with other foreign subsidiaries, and business ties may explain why foreign firms adopt a transactional or a relational approach to CPA. We test our hypotheses using a sample of 105 subsidiaries of foreign firms in India. We find that unrelated diversification and close integration with other subsidiaries of their parent firm makes subsidiaries more likely to adopt a transactional approach, whereas local resource criticality and ties to local businesses makes subsidiaries less likely to use a transactional approach to CPA. Our findings enhance our understanding of the factors that determine foreign firms’ choice of approaches to CPA in emerging economies
Peak effect in laser ablated DyBa2Cu3O7-d films at microwave frequencies at subcritical currents
In this paper we report the observation of a peak in the microwave surface
resistance (at frequencies ~10GHz) of laser ablated DyBa2Cu3O7-d films in
magnetic field ranging from 2 to 9kOe (||c) close to the superconducting
transition temperature (Tc(H)). The exact nature of peak is sample dependent
but it follows a general behaviour. The peak shifts to lower temperature when
the magnetic field is increased. It has strong frequency dependence and the
peak is pronounced at frequencies close to the depinning frequency of the flux
line lattice. From the observed temperature and field dependence we argue that
this peak is associated with the order disorder transition of the flux line
lattice close to Tc(H).Comment: 8 pages, 2 pages (accepted for publication in JAP, Intermag symposium
proceeding
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