45 research outputs found
BRAIN-COMPUTER-INTERFACE: VARIOUS SIGNAL ACQUISITION APPROACHES
This article addresses to the fundamental approaches for signal acquisition in Brain-Computer-Interface technology. Signal acquisition approaches are broadly classified into three major categories as Invasive-Approach, Semi-Invasive-Approach and Non-Invasive-Approach. In this context first of all we discussed the invasive approach in which electrical signals to be extracted from gray matter of the brain by neurosurgery, than semi invasive approach discussed in which electrical signals to be extracted from outside the gray matter by using electrocorticography technique. After that we discussed non invasive approach in detail including various techniques as EEG, MEG, EMG, MRI, TMS, PET, CT, NIRS, EROS, fNIRS, and fMRI.
Keywords: Neurosurgery, Craniotomy, SQUID, Radioactive Tracer, Multivariate Calibration
Exploring the impact of using alternative assessments on students' learning during the pandemic
Most of us are aware of the circumstances in which the learning has happened during the COVID-19 affected years. In this research paper we have taken up case study of one module named Data Structure and Algorithms to demonstrate the effects of new policy on this module. The main challenges faced while adopting to the new policy on alternate assessment design was retaining the quality of assessments to the tune of earlier appreciated levels. The appreciated efforts include the design of assignments that avoid similarity issues arising due to plagiarism, memorization, and coding against the clock. An effort has also been made to identify and utilize an on-line evaluation tool which is of immense help for the teachers involved in the evaluation process. A comparative analysis has been done to clearly distinguish between the top performers and the average performers. Further analysis and comparison of overall performance with the respective CGPA have shown exceptionally accurate results, which clearly indicate that the overall learning during the special semester is equally comparable with earlier semesters
How to stop disproportionation of a hydrochloride salt of a very weakly basic compound in a non-clinical suspension formulation
Our objectives were to stabilize a non-clinical suspension for use in toxicological studies and to develop methods to investigate the stability of the formulation in terms of salt disproportionation. The compound under research was a hydrochloride salt of a practically insoluble discovery compound ODM-203. The first of the three formulation approaches was a suspension prepared and stored at room temperature. The second formulation was stabilized by pH adjustment. In the third approach cooling was used to prevent salt disproportionation. 5 mg/mL aqueous suspension consisting of 20 mg/mL PVP/VA and 5 mg/mL Tween 80 was prepared for each of the approaches. The polymer was used as precipitation inhibitor to provide prolonged supersaturation while Tween 80 was used to enhance dissolution and homogeneity of the suspension. The consequences of salt disproportionation were studied by a small-scale in vitro dissolution method and by an in vivo pharmacokinetic study in rats. Our results show that disproportionation was successfully suppressed by applying cooling of the suspension in an ice bath at 2-8 degrees C. This procedure enabled us to proceed to the toxicological studies in rats. The in vivo study results obtained for the practically insoluble compound showed adequate exposures with acceptable variation at each dose level.Peer reviewe
Herbex-kid Inhibits Immediate Hypersensitivity Reactions in Mice and Rats
Herbex-kid (HK), a polyherbal formulation was evaluated in various experimental allergic models of Type I hypersensitivity reactions. Compound 48/80 (C 48/80) has been shown to induce rat mesentery mast cell degranulation and HK (1.07, 10.75 and 107.5 mg ml−1) inhibited the mast cell degranulation in a dose dependent manner. HK (1.07, 10.75 and 107.5 mg kg−1; p.o.) showed dose-dependent protection against C 48/80 induced systemic anaphylaxis in male Balb/C mice. In active anaphylaxis model, male Wistar rats orally administered with 10.75 and 107.5 mg kg−1 of HK showed significant (P < 0.01) protection against mast cell degranulation, while in passive anaphylaxis model, only at 107.5 mg kg−1 showed significant (P < 0.01) reduction in mast cell degranulation. HK at all dose levels was able to significantly decrease the time spent in nasal rubbing in Wistar rats sensitized to ovalbumin, while only at 107.5 mg kg−1 it showed significant (P < 0.01) reduction in number of sneezes. In C 48/80-induced skin itch model, all dose levels of HK significantly (P < 0.001) decreased the time spent in itching and the number of itches. HK did not produce any significant inhibition in histamine induced contraction in guinea pig ileum. From the above findings we conclude that the HK possesses antiallergic activity mediated by reducing of the release mediators from mast cells and also by 5-HT antagonism without the involvement of histamine (H1) receptors
A review on herbal antiasthmatics
In traditional systems of medicine, many plants have been documented to be useful for the treatment of various respiratory disorders including asthma. In the last two decades the use of medicinal plants and natural products has been increased dramatically all over the world. Current synthetic drugs used in pharmacotherapy of asthma are unable to act at all the stages and targets of asthma. However some herbal alternatives employed in asthma are proven to provide symptomatic relief and assist in the inhibition of disease progression also. The herbs have shown interesting results in various target specific biological activities such as bronchodilation, mast cell stabilization, anti-anaphylactic, anti-inflammatory, anti-spasmodic, anti-allergic, immunomodulatory and inhibition of mediators such as leukotrienes, lipoxygenase, cyclooxygenase, platelet activating, phosphodiesterase and cytokine, in the treatment of asthma. This paper is an attempt to classify these pharmacological and clinical findings based on their possible mechanism of action reported. It also signifies the need for development of polyherbal formulations containing various herbs acting at particular sites of the pathophysiological cascade of asthma for prophylaxis as well as for the treatment of asthma
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Enhanced performance of ultrathin n-i-p and p-i-n perovskite solar cells via light trapping: a simulation study employing Lambertian back reflector
In this study, the effectiveness of a Lambertian back reflector for trapping light in a MAPbI _3 perovskite solar cellhas been investigated. The propagation of collimated and diffuse light in the cell has been modelled using the transfer-matrix method and the radiative transfer equation respectively. We show that in the presence of such a reflector, the population of tail states at wavelengths beyond the band-edge of a conventional cell can be substantially increased. As a result of this enhanced light absorption, the power conversion efficiency of a 600 nm thick active layer in a conventional n-i-p (p-i-n) cell is shown to be attainable with a reduced thickness of 300 nm (200 nm) in the presence of light trapping. The effect of photon recycling to increase the open circuit voltage in these structures has also been studied for different thicknesses of the active layer. An increased open circuit voltage in the range 125–145 mV is observed for a Lambertian back reflector as compared to 155–170 mV increase seen in a conventional cell with metallic back reflector
Exploring the impact of using alternative assessments on students' learning during the pandemic
Most of us are aware of the circumstances in which the learning has happened during the COVID-19 affected years. In this research paper we have taken up case study of one module named Data Structure and Algorithms to demonstrate the effects of new policy on this module. The main challenges faced while adopting to the new policy on alternate assessment design was retaining the quality of assessments to the tune of earlier appreciated levels. The appreciated efforts include the design of assignments that avoid similarity issues arising due to plagiarism, memorization, and coding against the clock. An effort has also been made to identify and utilize an on-line evaluation tool which is of immense help for the teachers involved in the evaluation process. A comparative analysis has been done to clearly distinguish between the top performers and the average performers. Further analysis and comparison of overall performance with the respective CGPA have shown exceptionally accurate results, which clearly indicate that the overall learning during the special semester is equally comparable with earlier semesters