Journals
2018 EN
Firdaus Jannat Ul · Habib Anwar · Siddiqui Nadeem
+4 more
A series of newer benzothiazolotriazine derivatives ( 4a–k ) was designed, synthesized, and characterized as anticonvulsant agents against the two classically used MES and scPTZ animal models. The synthesized derivatives were tested in vivo in both the animal models, followed by a neurotoxicity study by the rotarod method. Compound 4e , 8‐chloro‐4‐(2‐chlorocyclohexa‐1,5‐dien‐1‐yl)‐2‐((4‐methoxybenzyl)thio)‐10a H ‐benzo[4,5]thiazolo[3,2a][1,3,5]triazine was found most promising among the series in both the animal models, with no neurotoxicity. From this it may be confirmed that the presence of a methoxy (OCH 3 ) group at the lipophilic aryl ring was showing high anticonvulsant potency. In the molecular modeling study, compound 4e (docking score = −8.70) showed important hydrogen bond interaction with the amino acids LYS 329, SER 137, GLY 136 and π–π interactions with PHE 189 at the active site of GABA‐AT. These derivatives can be further explored for the development of newer/novel anticonvulsant agents.
Journals
2018 EN
Chandra Soumen · Chowdhuri Angshuman Ray · Laha Dipranjan
+1 more
A facile and novel strategy to synthesize nitrogen‐ and phosphorous‐doped carbon dots (NPCDs) by single step pyrolysis method is described here. Citric acid is used as carbon source and di‐ammonium hydrogen phosphate is used as both nitrogen and phosphorous sources, respectively. Through the extensive study on optical properties, morphology and chemical structures of the synthesized NPCDs, it is found that as‐synthesized NPCDs exhibited good excitation‐dependent luminescence property, spherical morphology and high stability. The obtained NPCDs are stable in aqueous medium and possess a quantum yield of 10.58%. In this work, a new assay method is developed to detect iodide ions using the synthesized NPCDs. Here, the inner filter effect is applied to detect the iodide ion and exhibited a wide linear response concentration range (10–60 μM) with a limit of detection (LOD) of 0.32 μM. Furthermore, the synthesized NPCDs are used for the selective detection of iron(III) (Fe 3+ ) ions and cell imaging. Fe 3+ ions sensing assay shows a detection range from 0.2 to 30 μM with a LOD of 72 nM. As an efficient photoluminescence sensor, the developed NPCDs have an excellent biocompatibility and low cytotoxicity, allowing Fe 3+ ion detection in HeLa cells.
Journals
2018 EN
Budhiraja Gaurav · Sahu Neety · Subramanian Anuradha
Human mesenchymal stem cells (hMSCs) hold great potential for cellular based therapeutics and tissue engineering applications and their expansion is an interesting prospect due to their low availability from in vivo sources. Therefore, this study investigated the effect of continuous‐wave low‐intensity ultrasound (LIUS) at 5.0‐MHz and 14.0‐kPa (<20 mW cm −2 ) on the proliferative capacity, colony‐formation efficiency, genetic stability, and differentiation potential of hMSCs. Additionally, potential signaling pathways involved in LIUS‐mediated proliferation of hMSCs are studied. Compared to non‐stimulated controls, LIUS‐treated hMSCs shows a 1.9‐fold greater colony‐forming efficiency and 2.5‐fold higher rate of cell proliferation, respectively. Differential staining and qRT‐PCR analysis for selective chondrogenic, osteogenic, and adipogenic markers further confirmed that the LIUS treatment did not impact the multipotency of hMSCs. LIUS‐treated hMSCs expressed normal male karyotype. The synthesis of cyclin‐D1, a master regulator of cellular proliferation, is upregulated under LIUS and its enhanced mRNA expression under LIUS is noted to be mediated by the activation of both MAPK/ERK and PI3K/AKT pathways. In conclusion, LIUS promotes proliferation and self‐renewal capacity of hMSCs.
Journals
2018 EN
Parhi Dayal R. · Sahu Chinmaya · Kumar Priyadarshi Biplab
This paper is aimed at designing a navigation strategy for humanoid robots using a hybridised technique consisting of adaptive particle swarm optimisation and adaptive ant colony optimisation. The inputs to the navigational controller are the front obstacle distance, left obstacle distance, and right obstacle distance, and the output is the required final turning angle to reach the target position. Here, the governing parameters of the adaptive ant colony optimisation technique are optimised by using adaptive particle swarm optimisation method. These optimised parameters are subsequently used by the adaptive ant colony optimisation technique to get the final turning angle by which the humanoid navigates in a cluttered environment. Here, navigation is performed in both static and dynamic environments. To avoid the intercollision among the humanoids, a Petri‐net controller has been designed and implemented along with the proposed hybridised method. Humanoid navigation is performed in both simulated and experimental environments, and a comparison is done between them. Finally, the proposed controller is compared with the developed method by other researchers.
Journals
2018 EN
Sahu Gajanan · Gupta Navneet Kumar · Kotha Akhil
+5 more
Depletion of oil reserves, increasing prices of petroleum products, and environmental concerns related to air pollution are the main driving forces for utilizing renewable energy resources to replace fossil fuels. Vegetable oils can be used to produce biodiesel. Biodiesel is obtained by transesterification of vegetable oil with alcohol using homogeneous or heterogeneous catalysts. In the industry, biodiesel is produced by heterogeneous catalysts due to high activity and selectivity, better reusability, reduction in processing steps, and wastes. The catalytic activity of catalysts depends on the strength and type of intrinsic basic or/and acid properties. Biodiesel production using heterogenous catalysts depends on the various reaction parameters such as reaction time, temperature, molar ratio of alcohol to oil, catalyst amount, and stirring speed. In this paper, the catalytic transesterification of various feedstocks such as edible oil, non‐edible oil, and waste using heterogeneous catalysts has been reviewed and optimization parameters for maximum biodiesel production have been summarized.
Journals
2018 EN
Prashanth Billa · Bhandari Mamta · Ravi Satyam
+2 more
New three‐coordinate and electronically unsaturated aluminum hydride [ L AlH] + [HB(C 6 F 5 ) 3 ] − ( L H=[{(2,6‐ i Pr 2 C 6 H 3 N)P(Ph 2 )} 2 N]H) and aluminum methyl [ L AlMe] + [MeB(C 6 F 5 ) 3 ] − cations have been prepared. The quantitative estimation of Lewis acidity by Gutmann–Beckett method revealed [ L AlH] + [HB(C 6 F 5 ) 3 ] − to be better Lewis acid than B(C 6 F 5 ) 3 and AlCl 3 making these compounds ideal catalysts for Lewis acid‐mediated reactions. To highlight that the work is of fundamental importance, catalytic hydroboration of aliphatic and aromatic aldehydes and ketones have been demonstrated. Important steps of the catalytic cycle have been probed by using multinuclear NMR measurements, including successful characterization of the proposed aluminum benzyloxide cationic intermediate, [ L Al‐O‐CH 2 Ph] + [HB(C 6 F 5 ) 3 ] − . The proposed catalytic cycle has been found to be consistent with experimental observations and computational studies clearly indicating the migration of hydride from cationic aluminum center to the carbonyl carbon is the rate‐limiting step of the catalytic cycle.
Journals
2018 EN
Ghosh Arindam · Dash Syamasrit · Srinivasan A.
+3 more
Syntheses of core‐modified 24π pentaphyrin 7 and 20π homoporphyrin 8 are reported. The freebase form of 7 exhibits optical and 1 H NMR spectroscopic behavior corresponding to a 4nπ nonaromatic topology at 298 K. However, upon lowering the temperature to 188 K, 7 exhibits weak aromaticity because of a small conformational change. Protonation of the imine pyrrolic nitrogen atoms results in sharpening of the absorption band with more than 100 nm red shift and two‐fold increase in ϵ values. The 1 H NMR spectra show large shielding and deshielding of specific protons accompanied by twisting of pyrrole and thiophene rings from the mean plane of the macrocycle. These observations suggest a major structural change upon protonation. The single‐crystal X‐ray structure of protonated 7 a reveals a severe twisting of the macrocycle, especially at the ethene bridge, and the two thiophene rings adjacent to the ethene bridge are pointed above and below the plane of the ethene bridge (49.07 ° and 49.08°). The nucleus‐independent chemical shift (NICS) values calculated at the center of the macrocycle for the freebase and protonated derivatives of 7 a and 7 b are −5.6, −8.3 ppm and −5.3, −8.4 ppm, respectively. The anisotropy‐induced current density (AICD) plots suggest a clockwise circulation of π electrons. Taken together, the changes occurring in the optical spectra, 1 H NMR spectra, single‐crystal X‐ray structure and NICS calculation reflect a Möbius aromatic topology for protonated 7 . However, the homoporphyrin 8 remains nonaromatic both in the freebase and protonated form.
Journals
2018 EN
Sahu Dillip Kumar · Pal Tapas · Sahu Kalyanasis
A new phase transfer strategy to convert aqueous phase protein‐protected nanomaterials into fluorescent nanoclusters in the reverse micellar environment is introduced using bovine serum albumin (BSA)‐protected silver nanoclusters (AgNCs) and nanoparticles (AgNPs) as an example. The basic pH employed in the fabrication of protein‐protected nanoclusters induces the the protein capping to be negatively charged and facilitates the transfer process of the nanomaterials from aqueous phase to a cationic gemini surfactant (16‐2‐16)/hexane/hexanol/water reverse micelle (RM) phase. The original fluorescence characteristics of the seed nanocluster is retained after the transfer process. Strikingly, when both the nanomaterials (AgNCs and AgNPs) coexist in the aqueous feed solution, they are exclusively converted into uniform nanoclusters in the RM extract with enhanced fluorescence intensity.
Journals
2018 EN
Shanmukaraj Devaraj · Kretschmer Katja · Sahu Tuhin
+4 more
The development of sodium‐ion batteries has been hindered so far by the large irreversible capacity of hard carbon anodes and other anode materials in the initial few cycles, as sodium ions coming from cathode materials is consumed in the formation of the solid–electrolyte interface (SEI) and irreversibly trapped in anodes. Herein, the successful synthesis of an environmentally benign and cost‐effective sodium salt (Na 2 C 4 O 4 ) is reported that could be applied as additive in cathodes to solve the irreversible‐capacity issues of anodes in sodium‐ion batteries. When added to Na 3 (VO) 2 (PO 4 ) 2 F cathode, the cathode delivered a highly stable capacity of 135 mAh g −1 and stable cycling performance. The water‐stable Na 3 (VO) 2 (PO 4 ) 2 F cathode in combination with a water‐soluble sacrificial salt eliminates the need for using any toxic solvents for laminate preparation, thus paving way for greener electrode fabrication techniques. A 100 % increase in capacity of sodium cells (full‐cell configuration) has been observed when using the new sodium salt at a C‐rate of 2C. Regardless of the electrode fabrication technique, this new salt finds use in both aqueous and non‐aqueous cathode‐fabrication techniques for sodium‐ion batteries.
Journals
2018 EN
Dixit Dharmendra · Sahu P. R.
Summary Performance of dual‐hop decode‐and‐forward relay system with selection‐combining receiver is analyzed over Rice fading channels. The following closed‐form expressions of performance metrics are derived: moment generating function for selection‐combining receiver output signal‐to‐noise ratio, exact average bit error rate of noncoherent modulations, approximate average symbol error rate for coherent modulations, and outage probability. We also obtain simple asymptotic expressions for moment generating function, exact average bit error rate, average symbol error rate, and outage probability, which are useful to characterize the diversity order and the coding gain. The optimal power allocation analysis suggests that the optimal power allocation factor is independent of total signal‐to‐noise ratio and source‐to‐destination link fading parameters. The accuracy of the obtained analytical expressions are supported by computer simulation results.