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Fulltext The potential of incorporation of binary salts and ionic liquid in P(VP-co-VAc) gel polymer electrolyte in electrochemical and photovoltaic performances

Ming NH, Ramesh S, Ramesh K

Sci Rep, 2016 06 08;6:27630.
PMID: 27273020 DOI: 10.1038/srep27630

In this study, dye-sensitized solar cells (DSSCs) has been assembled with poly(1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) gel polymer electrolytes (GPEs) which have been incorporated with binary salt and an ionic liquid. The potential of this combination was studied and reported. The binary salt system GPEs was having ionic conductivity and power conversion efficiency (PCE) that could reach up to 1.90 × 10(-3) S cm(-1) and 5.53%, respectively. Interestingly, upon the addition of the ionic liquid, MPII into the binary salt system the ionic conductivity and PCE had risen steadily up to 4.09 × 10(-3) S cm(-1) and 5.94%, respectively. In order to know more about this phenomenon, the electrochemical impedance studies (EIS) of the GPE samples have been done and reported. Fourier transform infrared studies (FTIR) and thermogravimetric analysis (TGA) have also been studied to understand more on the structural and thermal properties of the GPEs. The Nyquist plot and Bodes plot studies have been done in order to understand the electrochemical properties of the GPE based DSSCs and Tafel polarization studies were done to determine the electrocatalytic activity of the GPE samples.
Fulltext Hydroxypropyl Cellulose Based Non-Volatile Gel Polymer Electrolytes for Dye-Sensitized Solar Cell Applications using 1-methyl-3-propylimidazolium iodide ionic liquid

Khanmirzaei MH, Ramesh S, Ramesh K

Sci Rep, 2015;5:18056.
PMID: 26659087 DOI: 10.1038/srep18056

Gel polymer electrolytes using imidazolium based ionic liquids have attracted much attention in dye-sensitized solar cell applications. Hydroxypropyl cellulose (HPC), sodium iodide (NaI), 1-methyl-3-propylimidazolium iodide (MPII) as ionic liquid (IL), ethylene carbonate (EC) and propylene carbonate (PC) are used for preparation of non-volatile gel polymer electrolyte (GPE) system (HPC:EC:PC:NaI:MPII) for dye-sensitized solar cell (DSSC) applications. The highest ionic conductivity of 7.37 × 10(-3) S cm(-1) is achieved after introducing 100% of MPII with respect to the weight of HPC. Temperature-dependent ionic conductivity of gel polymer electrolytes is studied in this work. XRD patterns of gel polymer electrolytes are studied to confirm complexation between HPC polymer, NaI and MPII. Thermal behavior of the GPEs is studied using simultaneous thermal analyzer (STA) and differential scanning calorimetry (DSC). DSSCs are fabricated using gel polymer electrolytes and J-V centeracteristics of fabricated dye sensitized solar cells were analyzed. The gel polymer electrolyte with 100 wt.% of MPII ionic liquid shows the best performance and energy conversion efficiency of 5.79%, with short-circuit current density, open-circuit voltage and fill factor of 13.73 mA cm(-2), 610 mV and 69.1%, respectively.
Effect of 1-Hexyl-3-Methylimidazolium Iodide Ionic Liquid on Ionic Conductivity and Energy Conversion Efficiency of Solid Polymer Electrolyte-Based Nano-Crystalline Dye-Sensitized Solar Cells

Khanmirzaei MH, Ramesh S, Ramesh K

J Nanosci Nanotechnol, 2020 Apr 01;20(4):2423-2429.
PMID: 31492257 DOI: 10.1166/jnn.2020.17192

Solid polymer electrolytes (SPEs) were prepared using rice starch as the polymer, sodium iodide (NaI) as the salt and 1-hexyl-3-methylimidazolium iodide (HMII) as the ionic liquid (IL). The solution casting technique was used for preparation of the PEs. The ionic conductivity and temperaturedependent properties of the PEs were measured and all the SPEs were found to follow the Arrhenius thermal activated model. Ionic conductivity increased as the percentage of ILs increased. The SPE containing 20% (wt) of HMII IL showed the highest ionic conductivity of 1.83×10-3 S/cm. Spectral and structural characterization of the PEs were performed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), respectively. The results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) indicate that the decomposition temperature (Tdc), glass transition temperatures (Tg) and melting points (Tm) shifted when complexation with HMII occurred. The PEs were used to fabricate dye-sensitized solar cells (DSSCs) and the DSSCs were analyzed under a 1-sun simulator. The SPE with the highest ionic conductivity displayed a short circuit current density (Jsc) of 9.07 (mA cm-2), open circuit voltage (Voc) of 0.58 (V), a fill factor (FF) of 0.65 and had the highest energy conversion efficiency of 3.42%.
Conducting polymer and its composite materials based electrochemical sensor for Nicotinamide Adenine Dinucleotide (NADH)

Omar FS, Duraisamy N, Ramesh K, Ramesh S

Biosens Bioelectron, 2016 May 15;79:763-75.
PMID: 26774092 DOI: 10.1016/j.bios.2016.01.013

Nicotinamide Adenine Dinucleotide (NADH) is an important coenzyme in the human body that participates in many metabolic reactions. The impact of abnormal concentrations of NADH significantly causes different diseases in human body. Electrochemical detection of NADH using bare electrode is a challenging task especially in the presence of main electroactive interferences such as ascorbic acid (AA), uric acid (UA) and dopamine (DA). Modified electrodes have been widely explored to overcome the problems of poor sensitivity and selectivity occurred from bare electrodes. This review gives an overview on the progress of using conducting polymers, polyelectrolyte and its composites (co-polymer, carbonaceous, metal, metal oxide and clay) based modified electrodes for the sensing of NADH. In addition, developments on the fabrication of numerous conducting polymer composites based modified electrodes are clearly described.
Fulltext pH responsive N-succinyl chitosan/Poly (acrylamide-co-acrylic acid) hydrogels and in vitro release of 5-fluorouracil

Bashir S, Teo YY, Naeem S, Ramesh S, Ramesh K

PLoS One, 2017;12(7):e0179250.
PMID: 28678803 DOI: 10.1371/journal.pone.0179250

There has been significant progress in the last few decades in addressing the biomedical applications of polymer hydrogels. Particularly, stimuli responsive hydrogels have been inspected as elegant drug delivery systems capable to deliver at the appropriate site of action within the specific time. The present work describes the synthesis of pH responsive semi-interpenetrating network (semi-IPN) hydrogels of N-succinyl-chitosan (NSC) via Schiff base mechanism using glutaraldehyde as a crosslinking agent and Poly (acrylamide-co-acrylic acid)(Poly (AAm-co-AA)) was embedded within the N-succinyl chitosan network. The physico-chemical interactions were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and field emission scanning electron microscope (FESEM). The synthesized hydrogels constitute porous structure. The swelling ability was analyzed in physiological mediums of pH 7.4 and pH 1.2 at 37°C. Swelling properties of formulations with various amounts of NSC/ Poly (AAm-co-AA) and crosslinking agent at pH 7.4 and pH 1.2 were investigated. Hydrogels showed higher swelling ratios at pH 7.4 while lower at pH 1.2. Swelling kinetics and diffusion parameters were also determined. Drug loading, encapsulation efficiency, and in vitro release of 5-fluorouracil (5-FU) from the synthesized hydrogels were observed. In vitro release profile revealed the significant influence of pH, amount of NSC, Poly (AAm-co-AA), and crosslinking agent on the release of 5-FU. Accordingly, rapid and large release of drug was observed at pH 7.4 than at pH 1.2. The maximum encapsulation efficiency and release of 5-FU from SP2 were found to be 72.45% and 85.99%, respectively. Kinetics of drug release suggested controlled release mechanism of 5-FU is according to trend of non-Fickian. From the above results, it can be concluded that the synthesized hydrogels have capability to adapt their potential exploitation as targeted oral drug delivery carriers.
Fulltext A new genus and species of arboreal toad with phytotelmonous larvae, from the Andaman Islands, India (Lissamphibia, Anura, Bufonidae)

Chandramouli SR, Vasudevan K, Harikrishnan S, Dutta SK, Janani SJ, Sharma R, et al.

Zookeys, 2016.
PMID: 26877687 DOI: 10.3897/zookeys.555.6522

A new bufonid amphibian, belonging to a new monotypic genus, is described from the Andaman Islands, in the Bay of Bengal, Republic of India, based on unique external morphological and skeletal characters which are compared with those of known Oriental and other relevant bufonid genera. Blythophryne gen. n. is distinguished from other bufonid genera by its small adult size (mean SVL 24.02 mm), the presence of six presacral vertebrae, an absence of coccygeal expansions, presence of an elongated pair of parotoid glands, expanded discs at digit tips and phytotelmonous tadpoles that lack oral denticles. The taxonomic and phylogenetic position of the new taxon (that we named as Blythophryne beryet gen. et sp. n.) was ascertained by comparing its 12S and 16S partial genes with those of Oriental and other relevant bufonid lineages. Resulting molecular phylogeny supports the erection of a novel monotypic genus for this lineage from the Andaman Islands of India.
Facile sonochemical synthesis of nanostructured NiO with different particle sizes and its electrochemical properties for supercapacitor application

Duraisamy N, Numan A, Fatin SO, Ramesh K, Ramesh S

J Colloid Interface Sci, 2016 Jun 01;471:136-144.
PMID: 26995554 DOI: 10.1016/j.jcis.2016.03.013

In this work, we demonstrate the influence of nickel oxides with divergent particle sizes as the working electrodes for supercapacitor application. The nanostructured nickel oxide (NiO) is synthesized via facile sonochemical method, followed by calcination process. The crystallinity and surface purity of prepared samples are clearly examined by X-ray diffraction and Raman analysis. NiO crystallinity is significantly increased with increasing calcination temperatures. The surface analysis confirmed that the calcination at 250°C exhibited nanoclutser like NiO with average particle size of ∼6nm. While increasing the calcination temperature beyond 250°C, hexagonal shaped NiO is observed with enhanced particle sizes. The electrochemical performance confirmed the good redox behavior of NiO electrodes. Moreover, NiO with average particle size of ∼6nm exhibited high specific capacitance of 449F/g at a scan rate of 5mV/s compared to other samples with particle sizes of ∼21nm (323F/g) and ∼41nm (63F/g). This is due to the good ion transfer mechanism and effective electrochemical utilization of the working electrode.
Rheological behavior of biodegradable N-succinyl chitosan-g-poly (acrylic acid) hydrogels and their applications as drug carrier and in vitro theophylline release

Bashir S, Teo YY, Ramesh S, Ramesh K, Mushtaq MW

Int J Biol Macromol, 2018 Oct 01;117:454-466.
PMID: 29807081 DOI: 10.1016/j.ijbiomac.2018.05.182

Novel pH sensitive N-succinyl chitosan-g-poly (acrylic acid) hydrogels were synthesized through free radical mechanism. Rheometer was used to observe the mechanical strength of the hydrogels. In vitro degradation was conducted in SIF (pH 7.4). The effect of concentration of monomers, initiator, and crosslinking agent and pH and ionic strength of NaCl, CaCl2, and AlCl3 on swelling of the hydrogels was observed. The results showed that equilibrium swelling ratio was highly influenced by concentration of monomers, initiator, and crosslinking agent concentration, and pH and salt solutions of NaCl, CaCl2, and AlCl3. The swelling kinetics revealed that swelling followed non-Fickian anomalous transport. Furthermore, theophylline loading (DL %) and encapsulation efficiency (EE %) of the hydrogels was in the range of 15.5 ± 0.15-22.8 ± 0.06% and 62 ± 0.15-91 ± 0.26%, respectively. The release of theophylline in physiological mediums was strongly influenced by the pH. The theophylline release was in the range of 51 ± 0.20-92 ± 0.12% in SIF and 7.4 ± 0.02-14.9 ± 0.03% in SGF (pH 1.2), respectively. The release data fitted well to Korsmeyer-Peppas model. The chemical activity of the theophylline suggested that drug maintained its chemical activity after release in vitro. The results suggest that synthesized hydrogels are excellent drug carriers.
Comparative Evaluation of Dental and Skeletal Fluorosis in an Endemic Fluorosed District, Salem, Tamil Nadu

Ramesh M, Malathi N, Ramesh K, Aruna RM, Kuruvilla S

J Pharm Bioallied Sci, 2017 Nov;9(Suppl 1):S88-S91.
PMID: 29284943 DOI: 10.4103/jpbs.JPBS_77_17

Background: High levels of fluoride in the drinking water, especially ground water, results in skeletal fluorosis which involves the bone and major joints. This study was conducted to assess the prevalence of skeletal fluorosis to compare with dental fluorosis in an endemically fluorosed population in the District of Salem, Tamil Nadu.
Materials and Methods: Institutional ethical clearance was obtained. A total of 206 patients who reported to the Department of Hematology for blood investigations were the participants in this study. Age, sex, place, weight, height, dental fluorosis, and skeletal complaints were noted down. Body mass index was calculated, and statistical analysis was performed.
Results: Dental fluorosis was present in 63.1% and absent in 36.9% of the samples reported. Skeletal fluorosis was present in 24.8% and was absent in 75.2%. A large number of the patients had knee pain and difficulty in bending. Chi-square test was used for statistical analysis. Skeletal fluorosis and age were compared and P value was 0.00 and was significant. Dental fluorosis and skeletal fluorosis were compared and P value was found to be 0.000 and significant.
Discussion and Conclusion: There is a need to take measures to prevent dental and skeletal fluorosis among the residents of Salem district. Calcium balance should be maintained, and fluoride intake should be minimized to reduce the symptoms. The government should provide water with low fluoride level for drinking and cooking. Once the symptoms develop, treatment largely remains symptomatic, using analgesics and physiotherapy.
Fulltext Maternal passive smoking and its effect on maternal, neonatal and placental parameters

Ramesh KN, Vidyadaran MK, Goh YM, Nasaruddin AA, Jammal ABE, Zainab S

Med J Malaysia, 2005 Aug;60(3):305-10.
PMID: 16379184

A study was undertaken to 1) determine the effects of tobacco smoke exposure on maternal and neonatal weight and body mass index (BMI) and placental weight, volume and surface area and 2) establish any correlations between the placental surface area, volume and weight with maternal and neonatal body weight and BMI in mothers exposed to cigarette smoke. A total of 154 full-term placentae, 65 from mothers exposed to tobacco smoke and 89 from non-exposed mothers were collected from Kuala Lumpur Maternity Hospital. The placental surface area was determined using a stereological grid, the volume by Scherle's method and the weight by using an electronic weighing machine. In general there were no differences in maternal, placental and neonatal parameters between the exposed and non-exposed groups. However, there were significant correlations between placental weight with maternal weight and maternal BMI in both exposed (r = 0.315; p = 0.013) and (r = 0.265; p = 0.038), and non-exposed (r = 0.224; p = 0.035) and (r = 0.241; p = 0.023) mothers. It was also found that the maternal weight on admission correlated significantly with placental weight in both Malay (r = 0.405; p = 0.020) and Indian (r = 0.553; p = 0.050) passive smokers. Correcting the placental parameters for the maternal weight had no effect on the results.
Fulltext An Approach to Solid-State Electrical Double Layer Capacitors Fabricated with Graphene Oxide-Doped, Ionic Liquid-Based Solid Copolymer Electrolytes

Fattah NFA, Ng HM, Mahipal YK, Numan A, Ramesh S, Ramesh K

Materials (Basel), 2016 Jun 06;9(6).
PMID: 28773573 DOI: 10.3390/ma9060450

Solid polymer electrolyte (SPE) composed of semi-crystalline poly (vinylidene fluoride-hexafluoropropylene) [P(VdF-HFP)] copolymer, 1-ethyl-3-methylimidazolium bis (trifluoromethyl sulphonyl) imide [EMI-BTI] and graphene oxide (GO) was prepared and its performance evaluated. The effects of GO nano-filler were investigated in terms of enhancement in ionic conductivity along with the electrochemical properties of its electrical double layer capacitors (EDLC). The GO-doped SPE shows improvement in ionic conductivity compared to the P(VdF-HFP)-[EMI-BTI] SPE system due to the existence of the abundant oxygen-containing functional group in GO that assists in the improvement of the ion mobility in the polymer matrix. The complexation of the materials in the SPE is confirmed in X-ray diffraction (XRD) and thermogravimetric analysis (TGA) studies. The electrochemical performance of EDLC fabricated with GO-doped SPE is examined using cyclic voltammetry and charge-discharge techniques. The maximum specific capacitance obtained is 29.6 F∙g(-1), which is observed at a scan rate of 3 mV/s in 6 wt % GO-doped, SPE-based EDLC. It also has excellent cyclic retention as it is able keep the performance of the EDLC at 94% even after 3000 cycles. These results suggest GO doped SPE plays a significant role in energy storage application.
Self-Healing, Flexible and Smart 3D Hydrogel Electrolytes Based on Alginate/PEDOT:PSS for Supercapacitor Applications

Badawi NM, Bhatia M, Ramesh S, Ramesh K, Kuniyil M, Shaik MR, et al.

Polymers (Basel), 2023 Jan 22;15(3).
PMID: 36771872 DOI: 10.3390/polym15030571

Hydrogel electrolytes for energy storage devices have made great progress, yet they present a major challenge in the assembly of flexible supercapacitors with high ionic conductivity and self-healing properties. Herein, a smart self-healing hydrogel electrolyte based on alginate/poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (alginate/PEDOT:PSS)(A/P:P) was prepared, wherein H2SO4 was employed as a polymeric initiator, as well as a source of ions. PEDOT:PSS is a semi-interpenetrating network (IPN) that has been used in recent studies to exhibit quick self-healing properties with the H₂SO₃ additive, which further improves its mechanical strength and self-healing performance. A moderate amount of PEDOT:PSS in the hydrogel (5 mL) was found to significantly improve the ionic conductivity compared to the pure hydrogel of alginate. Interestingly, the alginate/PEDOT:PSS composite hydrogel exhibited an excellent ability to self-heal and repair its original composition within 10 min of cutting. Furthermore, the graphite conductive substrate-based supercapacitor with the alginate/PEDOT:PSS hydrogel electrolyte provided a high specific capacitance of 356 F g-1 at 100 mV/s g-1. The results demonstrate that the A/P:P ratio with 5 mL PEDOT:PSS had a base sheet resistance of 0.9 Ω/square. This work provides a new strategy for designing flexible self-healing hydrogels for application in smart wearable electronics.
Weight, volume and surface area of placenta of normal pregnant women and their relation to maternal and neonatal parameters in Malay, Chinese and Indian ethnic groups

Sivarao S, Vidyadaran MK, Jammal AB, Zainab S, Goh YM, Ramesh KN

Placenta, 2002 10 4;23(8-9):691-6.
PMID: 12361688

This study was conducted to determine the effect of ethnicity on maternal, placental and neonatal parameters. Maternal, placental, and the newborn parameters were corrected for gestational age. The male:female sex ratio was 1:1.03. One hundred and forty-four freshly delivered placentae from 55 Malaysian, 51 Chinese, and 38 Indian normal healthy patients were collected and standard stereological methods used to estimate the placental parameters. Pearson's correlation, Spearman's correlation and 1-way ANOVA were used to test significance of differences. Placental surface area, placental weight and placental volume of Indians were lower than Malays (P< 0.05). Placental weight correlated significantly with neonatal length (r=0.527), birthweight (r=0.665), head circumference (r=0.371) and booking weight (r=0.193) while placental volume correlated with neonatal length (r=0.588), birthweight (r=0.688), head circumference (r=0.384), parity (r=0.202) and booking weight (r=0.219) at P< 0.05. Indian babies weight and length were less than Chinese and Malay babies (P< 0.05) while booking weight of Indian mothers was less than those of Chinese mothers (P< 0.05). Even after being corrected for booking weight, placental parameters of Indian patients were still significantly less than Malays and Chinese (P< 0.05).
Fulltext Anticorrosion, Thermal Degradation, and Hydrophobic Performances of Graphene/TiO2 Nanocomposite Coatings

Kumar SSA, Mohammed NB, Alduhaish O, Ramesh K, Ramesh S, Khan M, et al.

Polymers (Basel), 2023 May 23;15(11).
PMID: 37299227 DOI: 10.3390/polym15112428

Globally, researchers have devoted consistent efforts to producing excellent coating properties since coating plays an essential role in enhancing electrochemical performance and surface quality. In this study, TiO2 nanoparticles in varying concentrations of 0.5, 1, 2, and 3 wt.% were added into the acrylic-epoxy polymeric matrix with 90:10 wt.% (90A:10E) ratio incorporated with 1 wt.% graphene, to fabricate graphene/TiO2 -based nanocomposite coating systems. Furthermore, the properties of the graphene/TiO2 composites were investigated by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), ultraviolet-visible (UV-Vis) spectroscopy, water contact angle (WCA) measurements, and cross-hatch test (CHT), respectively. Moreover, the field emission scanning electron microscope (FESEM) and the electrochemical impedance spectroscopy (EIS) tests were conducted to investigate the dispersibility and anticorrosion mechanism of the coatings. The EIS was observed by determining the breakpoint frequencies over a period of 90 days. The results revealed that the TiO2 nanoparticles were successfully decorated on the graphene surface by chemical bonds, which resulted in the graphene/TiO2 nanocomposite coatings exhibiting better dispersibility within the polymeric matrix. The WCA of the graphene/TiO2 coating increased along with the ratio of TiO2 to graphene, achieving the highest CA of 120.85° for 3 wt.% of TiO2. Excellent dispersion and uniform distribution of the TiO2 nanoparticles within the polymer matrix were shown up to 2 wt.% of TiO2 inclusion. Among the coating systems, throughout the immersion time, the graphene/TiO2 (1:1) coating system exhibited the best dispersibility and high impedance modulus values (Z0.01 Hz), exceeding 1010 Ω cm2.
Fulltext Fabrication and characterization of graphene oxide-based polymer nanocomposite coatings, improved stability and hydrophobicity

Kumar SSA, M NB, Batoo KM, Wonnie Ma IA, Ramesh K, Ramesh S, et al.

Sci Rep, 2023 Jun 02;13(1):8946.
PMID: 37268705 DOI: 10.1038/s41598-023-35154-z

In this study, acrylic-epoxy-based nanocomposite coatings loaded with different concentrations (0.5-3 wt.%) of graphene oxide (GO) nanoparticles were successfully prepared via the solution intercalation approach. The thermogravimetric analysis (TGA) revealed that the inclusion of GO nanoparticles into the polymer matrix increased the thermal stability of the coatings. The degree of transparency evaluated by the ultraviolet-visible (UV-Vis) spectroscopy showed that the lowest loading rate of GO (0.5 wt.%) had completely blocked the incoming irradiation, thus resulting in zero percent transmittance. Furthermore, the water contact angle (WCA) measurements revealed that the incorporation of GO nanoparticles and PDMS into the polymer matrix had remarkably enhanced the surface hydrophobicity, exhibiting the highest WCA of 87.55º. In addition, the cross-hatch test (CHT) showed that all the hybrid coatings exhibited excellent surface adhesion behaviour, receiving 4B and 5B ratings respectively. Moreover, the field emission scanning electron microscopy (FESEM) micrographs confirmed that the presence of the functional groups on the GO surface facilitated the chemical functionalization process, which led to excellent dispersibility. The GO composition up to 2 wt.% showed excellent dispersion and uniform distribution of the GO nanoparticles within the polymer matrix. Therefore, the unique features of graphene and its derivatives have emerged as a new class of nanofillers/inhibitors for corrosion protection applications.
Fulltext Fundamental Concepts of Hydrogels: Synthesis, Properties, and Their Applications

Bashir S, Hina M, Iqbal J, Rajpar AH, Mujtaba MA, Alghamdi NA, et al.

Polymers (Basel), 2020 Nov 16;12(11).
PMID: 33207715 DOI: 10.3390/polym12112702

In the present review, we focused on the fundamental concepts of hydrogels-classification, the polymers involved, synthesis methods, types of hydrogels, properties, and applications of the hydrogel. Hydrogels can be synthesized from natural polymers, synthetic polymers, polymerizable synthetic monomers, and a combination of natural and synthetic polymers. Synthesis of hydrogels involves physical, chemical, and hybrid bonding. The bonding is formed via different routes, such as solution casting, solution mixing, bulk polymerization, free radical mechanism, radiation method, and interpenetrating network formation. The synthesized hydrogels have significant properties, such as mechanical strength, biocompatibility, biodegradability, swellability, and stimuli sensitivity. These properties are substantial for electrochemical and biomedical applications. Furthermore, this review emphasizes flexible and self-healable hydrogels as electrolytes for energy storage and energy conversion applications. Insufficient adhesiveness (less interfacial interaction) between electrodes and electrolytes and mechanical strength pose serious challenges, such as delamination of the supercapacitors, batteries, and solar cells. Owing to smart and aqueous hydrogels, robust mechanical strength, adhesiveness, stretchability, strain sensitivity, and self-healability are the critical factors that can identify the reliability and robustness of the energy storage and conversion devices. These devices are highly efficient and convenient for smart, light-weight, foldable electronics and modern pollution-free transportation in the current decade.
Evaluation of the effect of precursor ratios on the electrochemical performances of binder-free NiMn-phosphate electrodes for supercapattery

Gerard O, Ramesh S, Ramesh K, Numan A, Norhaffis Mustafa M, Khalid M, et al.

J Colloid Interface Sci, 2024 Apr 16;667:585-596.
PMID: 38657542 DOI: 10.1016/j.jcis.2024.04.101

Binary metal phosphate electrodes have been widely studied for energy storage applications due to the synergistic effects of two different transition elements that able to provide better conductivity and stability. Herein, the battery-type binder-free nickel-manganese phosphate (NiMn-phosphate) electrodes were fabricated with different Ni:Mn precursor ratios via microwave-assisted hydrothermal technique for 5 min at 90 °C. Overall, NiMn3P electrode (Ni:Mn = 1:3) showed an outstanding electrochemical performance, displaying the highest specific (areal) capacity at 3 A/g of 1262.4 C/g (0.44 C/cm2), and the smallest charge transfer resistance of 108.8 Ω. The enhanced performance of NiMn3P electrode can be ascribed to the fully grown amorphous nature and small-sized flake and flower structures of NiMn3P electrode material on the nickel foam (NF) surface. This configuration offered a higher number of active sites and a larger exposed area, facilitating efficient electrochemical reactions with the electrolyte. Consequently, the NiMn3P//AC electrode combination was chosen to further investigate its performance in supercapattery. The NiMn3P//AC supercapattery exhibited remarkable energy density of 105.4 Wh/kg and excellent cyclic stability with 84.7% retention after 3000 cycles. These findings underscored the superior electrochemical performance of the battery-type binder-free NiMn3P electrode, and highlight its potential for enhancing the overall performance of supercapattery.
Fulltext Cobalt Oxide Nanograins and Silver Nanoparticles Decorated Fibrous Polyaniline Nanocomposite as Battery-Type Electrode for High Performance Supercapattery

Iqbal J, Numan A, Omaish Ansari M, Jafer R, Jagadish PR, Bashir S, et al.

Polymers (Basel), 2020 Nov 27;12(12).
PMID: 33261072 DOI: 10.3390/polym12122816

In this study, silver (Ag) and cobalt oxide (Co3O4) decorated polyaniline (PANI) fibers were prepared by the combination of in-situ aniline oxidative polymerization and the hydrothermal methodology. The morphology of the prepared Ag/Co3O4@PANI ternary nanocomposite was studied by scanning electron microscopy and transmission electron microscopy, while the structural studies were carried out by X-ray diffraction and X-ray photoelectron spectroscopy. The morphological characterization revealed fibrous shaped PANI, coated with Ag and Co3O4 nanograins, while the structural studies revealed high purity, good crystallinity, and slight interactions among the constituents of the Ag/Co3O4@PANI ternary nanocomposite. The electrochemical performance studies revealed the enhanced performance of the Ag/Co3O4@PANI nanocomposite due to the synergistic/additional effect of Ag, Co3O4 and PANI compared to pure PANI and Co3O4@PANI. The addition of the Ag and Co3O4 provided an extended site for faradaic reactions leading to the high specific capacity. The Ag/Co3O4@PANI ternary nanocomposite exhibited an excellent specific capacity of 262.62 C g-1 at a scan rate of 3 mV s-1. The maximum energy and power density were found to be 14.01 Wh kg-1 and 165.00 W kg-1, respectively. The cyclic stability of supercapattery (Ag/Co3O4@PANI//activated carbon) consisting of a battery type electrode demonstrated a gradual increase in specific capacity with a continuous charge-discharge cycle until ~1000 cycles, then remained stable until 2500 cycles and later started decreasing, thereby showing the cyclic stability of 121.03% of its initial value after 3500 cycles.
First report of the infectious spleen and kidney necrosis virus (ISKNV) infection in ornamental fishes in India

Girisha SK, Kushala KB, Nithin MS, Puneeth TG, Naveen Kumar BT, Vinay TN, et al.

Transbound Emerg Dis, 2021 Mar;68(2):964-972.
PMID: 33448668 DOI: 10.1111/tbed.13793

Infectious spleen and kidney necrosis virus (ISKNV), a member of family iridoviridae, reported for the first time in a wide range of ornamental fish species in India. Significant mortalities during the year 2018-19 were reported from a number of retailers in the region with various clinical signs. The samples of moribund, dead and apparently healthy ornamental fishes were collected from retailers, located in three districts of Karnataka, India. Out of 140 fish samples, 16 samples (11.42%) representing 10 different fish species were found positive to ISKNV by OIE listed primers and same samples were reported to amplify the major capsid protein (MCP) gene of ISKNV. Further, sequence analysis of MCP gene showed that all strains detected in this study were closely related to other documented isolates from different countries with an identity ranging from 98.76% to 100%. Further, they clustered in the clade of ISKNV, during the phylogenetic analysis. The sequence similarity was high (99.94%) to ISKNV strains from Japan, Australia and Malaysia. This is the first report of an ISKNV infection in India. Moreover, out of 10 ISKNV-positive fish species, three species were reported positive to ISKNV for the first time in the world. Further, the in vitro experiment showed the growth of virus in Asian sea bass cell line, which is a natural host of ISKNV. Therefore, considering the lethal nature of megalocytiviruses to infect a vast range of species, proper biosecurity measures need to be taken to control these emerging pathogens.
The malleable brain: plasticity of neural circuits and behavior - a review from students to students

Schaefer N, Rotermund C, Blumrich EM, Lourenco MV, Joshi P, Hegemann RU, et al.

J Neurochem, 2017 Jun 20.
PMID: 28632905 DOI: 10.1111/jnc.14107

One of the most intriguing features of the brain is its ability to be malleable, allowing it to adapt continually to changes in the environment. Specific neuronal activity patterns drive long-lasting increases or decreases in the strength of synaptic connections, referred to as long-term potentiation and long-term depression, respectively. Such phenomena have been described in a variety of model organisms, which are used to study molecular, structural, and functional aspects of synaptic plasticity. This review originated from the first International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Alpbach, Austria (Sep 2016), and will use its curriculum and discussions as a framework to review some of the current knowledge in the field of synaptic plasticity. First, we describe the role of plasticity during development and the persistent changes of neural circuitry occurring when sensory input is altered during critical developmental stages. We then outline the signaling cascades resulting in the synthesis of new plasticity-related proteins, which ultimately enable sustained changes in synaptic strength. Going beyond the traditional understanding of synaptic plasticity conceptualized by long-term potentiation and long-term depression, we discuss system-wide modifications and recently unveiled homeostatic mechanisms, such as synaptic scaling. Finally, we describe the neural circuits and synaptic plasticity mechanisms driving associative memory and motor learning. Evidence summarized in this review provides a current view of synaptic plasticity in its various forms, offers new insights into the underlying mechanisms and behavioral relevance, and provides directions for future research in the field of synaptic plasticity. Read the Editorial Highlight for this article on doi: 10.1111/jnc.14102.

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