Indian Institute of Technology Indore

About: Indian Institute of Technology Indore is a education organization based out in Indore, Madhya Pradesh, India. It is known for research contribution in the topics: Computer science & Chemistry. The organization has 1606 authors who have published 4803 publications receiving 66500 citations.

Ultrafast Charge-Separation in Triphenylamine-BODIPY-Derived Triads Carrying Centrally Positioned, Highly Electron-Deficient, Dicyanoquinodimethane or Tetracyanobutadiene Electron-Acceptors.

Abstract: A series of new triphenylamine (TPA)-substituted BODIPYs 1-3 have been designed and synthesized through the Pd-catalysed Sonogashira cross-coupling and [2+2] cycloaddition-retroelectrocyclization reactions in good yields. This procedure yielded highly electron-deficient tetracyanobutadiene (TCBD) or dicyanoquinodimethane (DCNQ) electron-acceptor units centrally located at the TPA-BODIPY system. As a consequence, significant perturbation of the photonic and electronic properties was observed. The triads 2 and 3 showed red-shifted absorption, in addition to a strong charge-transfer-type absorption in the case of 3. The electrochemical studies revealed multi-redox processes involving the TPA, TCBD or DCNQ and BODIPY entities. The computational studies were performed at the B3LYP/6-31G** level to elucidate the geometry and electronic structures. An energy level diagram established for triads 2 and 3 revealed that the photoinduced charge-separation from the 1 BODIPY* is thermodynamically possible. In addition, charge transfer from TPA to TCBD in 2 and DCNQ in 3 was also possible. These charge transfer mechanisms were confirmed by photochemical studies performed using time-resolved emission and femtosecond-transient-absorption studies in solvents of varying polarity. Ultrafast charge-separation has been witnessed in these closely spaced, strongly interacting triads. The charge-separated state returned to the ground state without populating the 3 BODIPY*.

Separation of Rhythms of EEG Signals Based on Hilbert-Huang Transformation with Application to Seizure Detection

Abstract: We present a new method for separation of the rhythms of the electroencephalogram (EEG) signal. The proposed method is based on the Hilbert-Huang transform (HHT). The HHT consists two steps namely empirical mode decomposition (EMD) and the Hilbert transform (HT). The EMD decomposes EEG signal into set of narrow-band intrinsic mode functions (IMFs), and the Hilbert transformation of these IMFs provide instantaneous frequency estimation of the IMFs. The instantaneous frequency estimation of IMFs have been used as a feature to identify the IMFs in order to separate rhythms of EEG signal. The central tendency measure (CTM) has been used to quantify the variability in second order difference (SOD) plots of rhythms of the EEG signal. The CTM parameter is very effective to discriminate epileptic seizure EEG signals from the seizure-free EEG signals. The experimental results show the effectiveness of the proposed method for epileptic seizure detection.

Heat transfer augmentation in double pipe water to air counter flow heat exchanger with helical surface disc turbulators

Abstract: Present investigation reports the effect of helical surface disc turbulators (HSDTs) on heat transfer and pressure drop characteristics in double pipe heat exchanger (DPHE). HSDTs has been utilized in the annulus region. Tests are conducted by insertion of HSDTs with various operating parameters including three different diameter ratios (DR = do/Di = 0.42, 0.475 and 0.54), three different helix angles (ɸ = 20°, 30° and 40°) and varied range of Reynolds Number (3500–10500). Water, used as hot fluid, flows in the inner tube, while air, used as cold fluid, flows through the annulus. The tests are conducted for air for uniform wall temperature condition. The heat exchanger with least diameter ratio and increased helix angle is found to exhibit the highest Nusselt number and friction factor. Results indicate that maximum enhancement is obtained for smallest diameter ratio (DR = 0.42) and helix angle (ɸ = 40°). The thermal performance factor is found to be greater than unity for each configuration studied with DPHE using HSDTs. Correlations have been developed Nusselt number, friction factor and thermal performance factor for Reynolds number varying between 3500–10,500.

Comorbidity Assessment Is Essential During COVID-19 Treatment

Abstract: Coronavirus disease 2019 (COVID-19) caused by SARS-CoV2 is associated with various comorbidities; cardiovascular diseases, hypertension, diabetes, liver, lung diseases, and neurological ailments. The majority of the dysfunctions mentioned above are often associated with endothelial deterioration, indicating that endothelium can be the target of SARS-CoV2. Our study is an exclusive observational study that quantitatively analyses COVID-19 related comorbidities. We retrieved the data of % population of COVID-19 hospitalized and deceased patients with associated comorbidities from publicly accessible portals of the five European countries. A two tailed t-test enabled us to determine the significant proportions of deaths compared to hospitalized patients with associated comorbidity. Our study revealed that deaths associated with cardiovascular diseases and diabetes are highly significant (p < 0.0001) compared to hospitalized in countries like Italy, France, and Spain unlike the Netherlands. Deaths from kidney diseases (Italy- p < 0.0001; Sweden- p < 0.0001; Netherlands- p = 0.0001; France- p = 0.0033) and neurological ailments (France- p = 0.0001; Netherlands- p < 0.0001) are significantly higher than the total hospitalized patients affected by the particular comorbidity. We have noted that deaths due to liver diseases are least associated with COVID-19 among all comorbidities. Intriguingly, immunodeficiency shows mixed outcomes in death proportions compared to the hospital admitted individuals. Besides, the treatment regime involves drugs like losartan, ACE inhibitors, angiotensin-receptor blockers, Remdesivir, Chloroquine, Hydroxychloroquine, etc. may modulate the severity of the comorbidities. These comorbidities can create chaos in the existing healthcare system and may worsen the disease outcome.

Delay regulated explosive synchronization in multiplex networks

Abstract: It is known that explosive synchronization (ES) in an isolated network of Kuramoto oscillators with inertia is significantly enhanced by the presence of time delay. Here we show that time delay in one layer of the multiplex network governs the transition to synchronization and ES in the other layers. We found that a single layer with time-delayed intra-layer coupling may experience a different type of transition to synchronization, e.g. ES or continuous, depending on the values of time delay. Importantly, the same type of transition is incorporated simultaneously in other layer(s) as well, irrespective of the intra-layer delay values. Hence, a suitable choice of time-delay in only one layer of a multiplex network can lead to a desired (either ES or continuous) transition simultaneously in the other layers, either directly or remotely connected to the delayed layer. These results offer a platform for a better understanding of the dynamics of those complex systems which are represented by the multilayered framework and contain time delays in the communication processes.