Predicting the Temperature Dependence of Surfactant CMCs Using Graph Neural Networks.

The critical micelle concentration (CMC) of surfactant molecules is an essential property for surfactant applications in the industry. Recently, classical quantitative structure-property relationship (QSPR) and graph neural networks (GNNs), a deep learning technique, have been successfully applied to predict the CMC of surfactants at room temperature. However, these models have not yet considered the temperature dependence of the CMC, which is highly relevant to practical applications. We herein develop a GNN model for the temperature-dependent CMC prediction of surfactants. We collected about 1400 data points from public sources for all surfactant classes, i.e., ionic, nonionic, and zwitterionic, at multiple temperatures. We test the predictive quality of the model for the following scenarios: (i) when CMC data for surfactants are present in the training of the model in at least one different temperature and (ii) CMC data for surfactants are not present in the training, i.e., generalizing to unseen surfactants. In both test scenarios, our model exhibits a high predictive performance of R2 ≥ 0.95 on test data. We also find that the model performance varies with the surfactant class. Finally, we evaluate the model for sugar-based surfactants with complex molecular structures, as these represent a more sustainable alternative to synthetic surfactants and are therefore of great interest for future applications in the personal and home care industries.

Digital Well-being Through the Use of Technology-A Perspective.

"No man is an island unto himself" - John Donne According to the World Health Organization, health is "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity." Our healthcare industry, public behaviors, and environment have grown exponentially with digital technologies in the era of the 4th industrial revolution. Due to rapid digitalization and easy availability of the internet, we are now online round the clock on our digital devices, leaving behind digital traces/information. These digital footprints serve as an increasingly fruitful data source for social scientists, including those interested in demographic research. The collection and use of digital data (quantitative and qualitative) also present numerous statistical and computational opportunities, further motivating the development of new research approaches to address health issues. In this paper, we have described the concept of digital well-being and proposed how we can use digital information for good health.

Performance Analysis of the Dielectrically Modulated Junction-Less Nanotube Field Effect Transistor for Biomolecule Detection.

The design of a high-performance Dielectrically Modulated Field Effect Transistor (DMFET) with smaller device dimension (channel length ≤ 100nm) has recently drawn significant research attention for point-of-care (POC) diagenesis applications. Driven by this paradigm, a Hetero-Gate Metal Dielectrically Modulated Junction-Less Nanotube Field Effect Transistor (DM-JLNFET) architecture is introduced and systematically investigated for label-free electrochemical biosensing application with the help of extensive numerical device simulations. The DM-JLNFET is carefully designed to exploit the advantages of superior gate control over channel electrostatics and electron injection component as well as strong immunity towards the short channel effects that lead to a notably high sensing performance compared to its conventional counterparts. In this context, the underlying physics of the transduction mechanism is analyzed in detail based on the device electrostatics and the carrier transport mechanism. The sensing performance of the proposed biosensor is quantified in terms of the drain current and threshold voltage sensitivities, which represents the relative modulations in these parameters with biomolecule conjugation. Typically, the DM-JLNFET exhibits a drain current and threshold voltage sensitivities as high as 1×10 12 and 0.70, respectively, for biomolecule dielectric constant above 2. Furthermore, the sensing performance demonstrates strong immunities towards non-uniform cavity occupancy. Finally, extensive comparative performance analysis with Dielectrically Modulated Nanowire Field Effect Transistor (DM-NWFET) is performed. The results exhibit that the proposed DM-JLNFET can offer more than 100% and eight orders of magnitude improvements in the threshold voltage and drain current sensitivities, respectively, for a range of small biomolecule dielectric constants.

Artificial intelligence enabled healthcare: A hype, hope or harm.

In this paper, we have described the health care problem (maldistribution of doctors) in India. Later, we have introduced the concept of artificial intelligence and we have described this technology with various examples, how it is rapidly changing the health care scenario across the world. We have also described the various advantages of artificial intelligence technology. At the end of the paper, we have raised some serious concerns regarding complete replacement of human based health care technology with artificial intelligence technology. Lastly, we concluded that we have to use artificial intelligent technology to prevent human sufferings/health care problems with proper caution.

Noninvasive Ventilation-assisted Bronchoscopy in High-risk Hypoxemic Patients.

BACKGROUND AND AIMS: Hypoxemic patients undergoing fiber-optic bronchoscopy (FOB) are at risk of worsening of respiratory failure requiring mechanical ventilation due to FOB procedure itself and its complications. As patients with respiratory failure are frequently managed by non-invasive ventilation (NIV); feasibility of FOB through NIV mask has been evaluated in some studies to avoid intubation. We describe here our own case series. MATERIALS AND METHODS: Clinical data of 28 FOB done through NIV mask in 27 intensive care unit (ICU) patients over 6 years period at our center was collected retrospectively and analysed. RESULTS: Study comprises 27 (17 male; 52±21.6 years age) hypoxemic (PaO2 71.3±14.2, on NIV and oxygen supplementation) patients. All FOB were done at bedside, 15 of them were given sedation for the procedure. Twenty four patients had bronchoalveolar lavage (BAL); three underwent bronchial biopsies, four brush cytology and seven transbronchial biopsies. In 10 patients lung or lobar collapse was reversed. There was no significant change between pre and post bronchoscopy ABG parameters except for improved post FOB PaO2 (p = 0.0032) and SpO2 (p = 0.0046). One patient (3.57%) developed late pneumothorax and 3 patients (10.7%) had bleeding after biopsy. Prior to bronchoscopy 17 (16 BIPAP, 1 CPAP) patients were already on NIV. Two patients required mechanical ventilation 6 hours after FOB due to subsequent clinical deterioration but could be weaned off later. One patient died on third day after FOB from acute myocardial infarction. CONCLUSION: Hypoxemic patients in ICU can safely undergo bedside diagnostic and simple therapeutic bronchoscopy with NIV support while mostly avoiding intubation and with low complication rates. HOW TO CITE THIS ARTICLE: Sircar M, Jha OK, Chabbra GS, Bhattacharya S. Noninvasive Ventilation-assisted Bronchoscopy in High-risk Hypoxemic Patients. Indian J Crit Care Med 2019;23(8):363-367.

Association of angiotensinogen gene SNPs and haplotypes with risk of hypertension in eastern Indian population.

BACKGROUND: Angiotensinogen (AGT) enzyme comprises a vital module of RAAS system that effectively controls the blood pressure and related cardiovascular functions. Ample association studies have reported the importance of AGT variants in cardiovascular and non-cardiovascular adversities. But lately, owing to the complexity of the many anomalies, the haplotype based examination of genetic variation that facilitates the identification of polymorphic sites which are located in the vicinity of the causative polymorphic site, gets greater appreciation. METHODS: In the present study, we have done genotype and haplotype analysis of AGT gene in reference to hypertension to confirm the association of the two in an Indian population. To accomplish this, we performed candidate SNPs analysis and construct possible haplotypes across the AGT promoter and gene region in 414 subjects (256 Hypertensive cases and 158 controls). RESULTS: We found four SNPs (rs11568020: A-152G and rs5050: A-20C in promoter; rs4762 and rs699 in exon2) and 3 haplotypes (H4, H7 and H8) that showed a stronger positive association with hypertension. The haplotype H2 was showing protective association with hypertension. CONCLUSION: The results of the present study confirmed and reestablished the role of AGT gene variants and their haplotypes in the causation of hypertension in Indian population and showed that haplotypes can provide stronger evidence of association.

Strong Reduction of Thermal Conductivity and Enhanced Thermoelectric Properties in CoSbS1-xSex Paracostibite.

In order to reduce the thermal conductivity of CoSbS, a newly developed thermoelectric semiconductor, we have aimed at intentionally induce atomic disorder in its structure. This endeavor was guided by Density Functional Theory(DFT) calculations which indicated that substituting sulfur with selenium might be easily achievable experimentally because of the low formation energy of this point defect. Thereby, CoSbS1-xSex compounds having 0 ≤ x ≤ 1 have been synthesized by solid state reaction. Besides the expected semiconducting paracostibite phase, we have observed the appearance of a semimetallic costibite phase, never reported experimentally before. This cross-fertilized theoretical and experimental approach allowed us to reduce by 50% the thermal conductivity of paracostibite and therefore reach a maximum zT of 0.62 at 730 K. This makes this entirely new CoSbS1-xSex alloy very attractive for further optimizations and potential usage in thermoelectric applications.

Two-Step Phase Transition in SnSe and the Origins of its High Power Factor from First Principles.

The interest in improving the thermoelectric response of bulk materials has received a boost after it has been recognized that layered materials, in particular SnSe, show a very large thermoelectric figure of merit. This result has received great attention while it is now possible to conceive other similar materials or experimental methods to improve this value. Before we can now think of engineering this material it is important we understand the basic mechanism that explains this unusual behavior, where very low thermal conductivity and a high thermopower result from a delicate balance between the crystal and electronic structure. In this Letter, we present a complete temperature evolution of the Seebeck coefficient as the material undergoes a soft crystal transformation and its consequences on other properties within SnSe by means of first-principles calculations. Our results are able to explain the full range of considered experimental temperatures.

Achieving optimum carrier concentrations in p-doped SnS thermoelectrics.

Tin(II)sulfide, SnS, is a commercially viable and environmentally friendly thermoelectric material. Recently it was shown how the carrier concentration and the thermoelectric power factor can be optimized by Ag-doping in a sulphur rich environment. Theoretical calculations lead to a fairly accurate estimation of the carrier concentration, whereas the potential of doping with Li(+) is strongly overestimated. Two principally ubiquitous effects that can result in decreasing the hole concentration, namely the formation of coupled defect complexes and oxidation of the dopant, are discussed as possible origins of this disagreement. It is shown that oxidation limits the chemical potential of Li beyond that already set by the formation of Li2S. This work serves as a comprehensive guide to achieve an efficient p-doped SnS thermoelectric material.

Spin transport properties of triarylamine-based nanowires.

Triarylamine-derivatives can self-assemble upon light irradiation in one-dimensional nanowires with remarkable hole transport properties. We use a combination of density functional theory and Monte Carlo simulations to predict the nanowires spin-diffusion length. The orbital nature of the nanowires valence band, namely a singlet π-like band localised on N, suggests that hyperfine coupling may be weak and that spin-orbit interaction is the primary source of intrinsic spin relaxation. Thus, we construct a model where the spin-orbit interaction mixes the spins of the valence band with that of three degenerate lower valence bands of sp(2) nature. The model includes also electron-phonon interaction with a single longitudinal mode. We find a room temperature spin-diffusion length of the order of 100 nm, which increases to 300 nm at 200 K. Our results indicate that triarylamine-based nanowires are attractive organic semiconductors for spintronics applications.

First principles study of the structural, electronic, and transport properties of triarylamine-based nanowires.

We investigate with state of the art density functional theory the structural, electronic, and transport properties of a class of recently synthesized nanostructures based on triarylamine derivatives. First, we consider the single molecule precursors in the gas phase and calculate their static properties, namely (i) the geometrical structure of the neutral and cationic ions, (ii) the electronic structure of the frontier molecular orbitals, and (iii) the ionization potential, hole extraction potential, and internal reorganization energy. This initial study does not evidence any direct correlation between the properties of the individual molecules and their tendency to self-assembly. Subsequently, we investigate the charge transport characteristics of the triarylamine derivatives nanowires, by using Marcus theory. For one derivative we further construct an effective Hamiltonian including intermolecular vibrations and evaluate the mobility from the Kubo formula implemented with Monte Carlo sampling. These two methods, valid respectively in the sequential hopping and polaronic band limit, give us values for the room-temperature mobility in the range 0.1-12 cm(2)/Vs. Such estimate confirms the superior transport properties of triarylamine-based nanowires, and make them an attracting materials platform for organic electronics.