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  1. Fulltext Malaysia-ACute CORonary syndromes Descriptive study (ACCORD): evaluation of compliance with existing guidelines in patients with acute coronary syndrome
    Ahmad WA, Ramesh SV, Zambahari R
    Singapore Med J, 2011 Jul;52(7):508-11.
    PMID: 21808962
    The ACute CORonary syndromes Descriptive study (ACCORD) is a prospective observational study that evaluates the management of acute coronary syndrome (ACS) in clinical practice and the use of antiplatelet agents in acute settings and after discharge. The secondary objective of this study was to obtain information on risk factors in a large cohort of patients with ACS.
    Comment in: Sachithanandan A. Malaysia-ACCORD study: tip of the cardiovascular iceberg--we must do better. Singapore Med J, 2011 Sep;52(9):702;
  2. Fulltext Prediction of conductivity by adaptive neuro-fuzzy model
    Akbarzadeh S, Arof AK, Ramesh S, Khanmirzaei MH, Nor RM
    PLoS One, 2014;9(3):e92241.
    PMID: 24658582 DOI: 10.1371/journal.pone.0092241
    Electrochemical impedance spectroscopy (EIS) is a key method for the characterizing the ionic and electronic conductivity of materials. One of the requirements of this technique is a model to forecast conductivity in preliminary experiments. The aim of this paper is to examine the prediction of conductivity by neuro-fuzzy inference with basic experimental factors such as temperature, frequency, thickness of the film and weight percentage of salt. In order to provide the optimal sets of fuzzy logic rule bases, the grid partition fuzzy inference method was applied. The validation of the model was tested by four random data sets. To evaluate the validity of the model, eleven statistical features were examined. Statistical analysis of the results clearly shows that modeling with an adaptive neuro-fuzzy is powerful enough for the prediction of conductivity.
  3. Fulltext Role of Natural Cross Linkers in Resin-Dentin Bond Durability: A Systematic Review and Meta-Analysis
    Anumula L, Ramesh S, Kolaparthi VSK, Kirubakaran R, Karobari MI, Arora S, et al.
    Materials (Basel), 2022 Aug 17;15(16).
    PMID: 36013786 DOI: 10.3390/ma15165650
    BACKGROUND: The role of endogenous Matrix Metallo Proteinases in resin dentin bond deterioration over time has been well documented. The present study aimed to systematically review the literature; in vitro and ex vivo studies that assessed the outcomes of natural cross-linkers for immediate and long-term tensile bond strength were included.

    METHODS: The manuscript search was carried out in six electronic databases-PubMed/MEDLINE, LILACS, SciELO, Cochrane, Web of Science and DOAJ, without publication year limits. Only manuscripts in English (including the translated articles) were selected, and the last search was performed in December 2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was followed.

    RESULTS: From the 128 potentially eligible studies, 48 full-text articles were assessed for eligibility. After eligibility assessment and exclusions, 14 studies were considered for systematic review and seven studies for meta-analysis. Amongst the selected studies for meta-analysis, three had a medium and four had a low risk of bias.

    CONCLUSIONS: It was evidenced by the available data that Proanthocyanidin is the most efficient natural cross-linker to date, in preserving the bond strength even after ageing.

  4. 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.
  5. Development of a bone substitute material based on alpha-tricalcium phosphate scaffold coated with carbonate apatite/poly-epsilon-caprolactone
    Bang LT, Ramesh S, Purbolaksono J, Long BD, Chandran H, Ramesh S, et al.
    Biomed Mater, 2015 Aug;10(4):045011.
    PMID: 26225725 DOI: 10.1088/1748-6041/10/4/045011
    Interconnected porous tricalcium phosphate ceramics are considered to be potential bone substitutes. However, insufficient mechanical properties when using tricalcium phosphate powders remain a challenge. To mitigate these issues, we have developed a new approach to produce an interconnected alpha-tricalcium phosphate (α-TCP) scaffold and to perform surface modification on the scaffold with a composite layer, which consists of hybrid carbonate apatite / poly-epsilon-caprolactone (CO3Ap/PCL) with enhanced mechanical properties and biological performance. Different CO3Ap combinations were tested to evaluate the optimal mechanical strength and in vitro cell response of the scaffold. The α-TCP scaffold coated with CO3Ap/PCL maintained a fully interconnected structure with a porosity of 80% to 86% and achieved an improved compressive strength mimicking that of cancellous bone. The addition of CO3Ap coupled with the fully interconnected microstructure of the α-TCP scaffolds coated with CO3Ap/PCL increased cell attachment, accelerated proliferation and resulted in greater alkaline phosphatase (ALP) activity. Hence, our bone substitute exhibited promising potential for applications in cancellous bone-type replacement.
  6. Biological responses of MC3T3-E1 on calcium carbonate coatings fabricated by hydrothermal reaction on titanium
    Bang LT, Shi R, Bui Duc L, Ramesh S, Shi X, Sugiura Y, et al.
    Biomed Mater, 2020 Jan 08.
    PMID: 31914435 DOI: 10.1088/1748-605X/ab6939
    Titainum (Ti) implants have been successfully used in orthopaedic and dental surgery. However, the poor early bone tissue integration is still a common failure. This could be modulated by improving material bonding or adhesion directly to bone though a surface roughening and/or a bioresorbable and osteoconductive coating. In this study, we report on the biological behavious of the Ti substrate with modified surface roughness and/or bioactive coating. The roughened Ti surface was prepared by acid etching reaction, and the calcium carbonate (CaCO3) coating on the substrates was synthesized by hydrothermal treatment of Ti in calcium citrate complexes. The study demonstrated that surface roughing of Ti alone did not improve the biological reponse of the MC3T3-E1 cells, however, CaCO3 coating on smooth Ti surface increased cell responses, and the affects were further enhanced in combination with Ti surface roughening. Larger cell area, greater cell proliferation and increased bone-like nodule formation were obtained on the CaCO3 coating of the roughened Ti surface. This was also supported by a higher ALP value obtained for the the coatings of roughened Ti surface. The cell behaviours found in the current study support further development of calcium carbonate coatings towards clinical application.
  7. 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.
  8. 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.
  9. 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.
  10. Fulltext Ultrasonication-mediated nitrogen-doped multiwalled carbon nanotubes involving carboxy methylcellulose composite for solid-state supercapacitor applications
    Basivi PK, Ramesh S, Kakani V, Yadav HM, Bathula C, Afsar N, et al.
    Sci Rep, 2021 May 10;11(1):9918.
    PMID: 33972653 DOI: 10.1038/s41598-021-89430-x
    In this study, a novel nanohybrid composite containing nitrogen-doped multiwalled carbon nanotubes/carboxymethylcellulose (N-MWCNT/CMC) was synthesized for supercapacitor applications. The synthesized composite materials were subjected to an ultrasonication-mediated solvothermal hydrothermal reaction. The synthesized nanohybrid composite electrode material was characterized using analytical methods to confirm its structure and morphology. The electrochemical properties of the composite electrode were investigated using cyclic voltammetry (CV), galvanic charge-discharge, and electrochemical impedance spectroscopy (EIS) using a 3 M KOH electrolyte. The fabricated composite material exhibited unique electrochemical properties by delivering a maximum specific capacitance of approximately 274 F g-1 at a current density of 2 A g-1. The composite electrode displayed high cycling stability of 96% after 4000 cycles at 2 A g-1, indicating that it is favorable for supercapacitor applications.
  11. A facile ultrasonic-aided biosynthesis of ZnO nanoparticles using Vaccinium arctostaphylos L. leaf extract and its antidiabetic, antibacterial, and oxidative activity evaluation
    Bayrami A, Alioghli S, Rahim Pouran S, Habibi-Yangjeh A, Khataee A, Ramesh S
    Ultrason Sonochem, 2019 Jul;55:57-66.
    PMID: 31084791 DOI: 10.1016/j.ultsonch.2019.03.010
    The synthesis of nanoparticles often result in the generation of harmful chemical pollutants. As such, many researchers have focused on developing green processes, which include the biosynthesis. In this research, ZnO nanoparticles were prepared using the leaf extract of whortleberry (Vaccinium arctostaphylos L.) via a simple ultrasonic-assisted method. The morphology, crystal size and structure, surface, thermal, and optical properties of the bio-mediated ZnO sample (ZnOext) were analyzed and compared with that produced without incorporating the extract (ZnOchem). The ZnO samples were evaluated for their antidiabetic, antibacterial, as well as their sono- and photo-catalytic performances. Initially, the samples were intraperitoneal injected to alloxan-diabetic rats to examine their treatment efficiency in terms of effects on fasting blood glucose, insulin, cholesterol, high-density lipoprotein, and total triglyceride levels. The ZnOext showed significantly higher efficiency for improving the health status of alloxan-diabetic rats in contrast with other tested treatments, vis. ZnOchem, insulin, and only leaf extract. In addition, both the ZnO samples were assessed against gram-negative and gram-positive bacteria and through sono- and photo-catalytic processes for removing rhodamine B, respectively. The results of this study indicated that not only the ZnOext sample was pollution free, it also exhibited higher potentials for treating diabetic rats, bacterial decontamination, and also oxidative removal of organic compounds under the influences of ultrasound and UV irradiations when compared with ZnOchem sample.
  12. Fulltext Research on Cartilage 3D Printing Technology Based on SA-GA-HA
    Chen Y, Gong Y, Shan L, Tan CY, Al-Furjan MS, Ramesh S, et al.
    Materials (Basel), 2023 Jul 28;16(15).
    PMID: 37570016 DOI: 10.3390/ma16155312
    Cartilage damage is difficult to heal and poses a serious problem to human health as it can lead to osteoarthritis. In this work, we explore the application of biological 3D printing to manufacture new cartilage scaffolds to promote cartilage regeneration. The hydrogel made by mixing sodium alginate (SA) and gelatin (GA) has high biocompatibility, but its mechanical properties are poor. The addition of hydroxyapatite (HA) can enhance its mechanical properties. In this paper, the preparation scheme of the SA-GA-HA composite hydrogel cartilage scaffold was explored, the scaffolds prepared with different concentrations were compared, and better formulations were obtained for printing and testing. Mathematical modeling of the printing process of the bracket, simulation analysis of the printing process based on the mathematical model, and adjustment of actual printing parameters based on the results of the simulation were performed. The cartilage scaffold, which was printed using Bioplotter 3D printer, exhibited useful mechanical properties suitable for practical needs. In addition, ATDC-5 cells were seeded on the cartilage scaffolds and the cell survival rate was found to be higher after one week. The findings demonstrated that the fabricated chondrocyte scaffolds had better mechanical properties and biocompatibility, providing a new scaffold strategy for cartilage tissue regeneration.
  13. 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.
  14. 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.
  15. 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.
  16. Evaluation of functional severity of coronary artery disease and fluid dynamics' influence on hemodynamic parameters: A review
    Govindaraju K, Badruddin IA, Viswanathan GN, Ramesh SV, Badarudin A
    Phys Med, 2013 May;29(3):225-32.
    PMID: 22704601 DOI: 10.1016/j.ejmp.2012.03.008
    Coronary Artery Disease (CAD) is responsible for most of the deaths in patients with cardiovascular diseases. Diagnostic coronary angiography analysis offers an anatomical knowledge of the severity of the stenosis. The functional or physiological significance is more valuable than the anatomical significance of CAD. Clinicians assess the functional severity of the stenosis by resorting to an invasive measurement of the pressure drop and flow. Hemodynamic parameters, such as pressure wire assessment fractional flow reserve (FFR) or Doppler wire assessment coronary flow reserve (CFR) are well-proven techniques to evaluate the physiological significance of the coronary artery stenosis in the cardiac catheterization laboratory. Between the two techniques mentioned above, the FFR is seen as a very useful index. The presence of guide wire reduces the coronary flow which causes the underestimation of pressure drop across the stenosis which leads to dilemma for the clinicians in the assessment of moderate stenosis. In such condition, the fundamental fluid mechanics is useful in the development of new functional severity parameters such as pressure drop coefficient and lesion flow coefficient. Since the flow takes place in a narrowed artery, the blood behaves as a non-Newtonian fluid. Computational fluid dynamics (CFD) allows a complete coronary flow simulation to study the relationship between the pressure and flow. This paper aims at explaining (i) diagnostic modalities for the evaluation of the CAD and valuable insights regarding FFR in the evaluation of the functional severity of the CAD (ii) the role of fluid dynamics in measuring the severity of CAD.
  17. Electrocoagulation treatment of raw landfill leachate using iron-based electrodes: Effects of process parameters and optimization
    Huda N, Raman AAA, Bello MM, Ramesh S
    J Environ Manage, 2017 Dec 15;204(Pt 1):75-81.
    PMID: 28865309 DOI: 10.1016/j.jenvman.2017.08.028
    The main problem of landfill leachate is its diverse composition comprising many persistent organic pollutants which must be removed before being discharge into the environment. This study investigated the treatment of raw landfill leachate using electrocoagulation process. An electrocoagulation system was designed with iron as both the anode and cathode. The effects of inter-electrode distance, initial pH and electrolyte concentration on colour and COD removals were investigated. All these factors were found to have significant effects on the colour removal. On the other hand, electrolyte concentration was the most significant parameter affecting the COD removal. Numerical optimization was also conducted to obtain the optimum process performance. Under optimum conditions (initial pH: 7.73, inter-electrode distance: 1.16 cm, and electrolyte concentration (NaCl): 2.00 g/L), the process could remove up to 82.7% colour and 45.1% COD. The process can be applied as a pre-treatment for raw leachates before applying other appropriate treatment technologies.
  18. 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.
  19. Fulltext Intramuscular injection of botulinum toxin for the treatment of wrist and finger spasticity after stroke
    Jahangir AW, Tan HJ, Norlinah MI, Nafisah WY, Ramesh S, Hamidon BB, et al.
    Med J Malaysia, 2007 Oct;62(4):319-22.
    PMID: 18551937 MyJurnal
    Botulinum toxin is effective in reducing spasticity post stroke. As there are limited data on post stroke spasticity in Asia, we undertake this study to determine the effectiveness and safety of intramuscular injection of botulinum toxin type-A (BTX-A), in the treatment of chronic focal post-stroke hand spasticity, and the impact of BTX-A on the activities of daily living and quality of life, in comparison to placebo, in Malaysian stroke patients. This was a randomized, double-blind, placebo-controlled study to assess the efficacy and safety of BTX-A in 27 subjects with wrist and finger spasticity after a stroke. The outcome measures were assessed with the Modified Ashworth Scale (MAS) to assess spasticity of the flexor muscles, Barthel Index (BI) for activities of daily living and EQ-5D and EQ VAS for quality of life. Assessments were performed at baseline and 1 and 3 months after injection. Compared to placebo, the BTX-A group had greater improvement in the flexor tone of the wrist and fingers (p = 0.001 and p < 0.001, respectively), at first month follow-up visit and sustained the improvement through to three months. Although there was an improvement in the measures of global function and quality of life in the BTX-A group, there was no significant improvement in between the two groups. No serious BTX-A related adverse effects were reported. The results of this study demonstrate that intramuscular injection of botulinum toxin A is safe and effective in the treatment of chronic focal post-stroke spasticity of the hand.
  20. Fulltext Hydrothermal synthesis of CuO@MnO2 on nitrogen-doped multiwalled carbon nanotube composite electrodes for supercapacitor applications
    Kakani V, Ramesh S, Yadav HM, Bathula C, Basivi PK, Palem RR, et al.
    Sci Rep, 2022 Sep 20;12(1):12951.
    PMID: 36127493 DOI: 10.1038/s41598-022-16863-3
    Nitrogen-doped multiwalled carbon nanotubes (N-MWCNTs) have been used to fabricate nanostructured materials for various energy devices, such as supercapacitors, sensors, batteries, and electrocatalysts. Nitrogen-doped carbon-based electrodes have been widely used to improve supercapacitor applications via various chemical approaches. Based on previous studies, CuO@MnO2 and CuO@MnO2/N-MWCNT composites were synthesized using a sonication-supported hydrothermal reaction process to evaluate their supercapacitor properties. The structural and morphological properties of the synthesized composite materials were characterized via Raman spectroscopy, XRD, SEM, and SEM-EDX, and the morphological properties of the composite materials were confirmed by the nanostructured composite at the nanometer scale. The CuO@MnO2 and CuO@MnO2/N-MWCNT composite electrodes were fabricated in a three-electrode configuration, and electrochemical analysis was performed via CV, GCD, and EIS. The composite electrodes exhibited the specific capacitance of ~ 184 F g-1 at 0.5 A g-1 in the presence of a 5 M KOH electrolyte for the three-electrode supercapacitor application. Furthermore, it exhibited significantly improved specific capacitances and excellent cycling stability up to 5000 GCD cycles, with a 98.5% capacity retention.
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