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Fulltext Chemical composition, antioxidant and antimicrobial potential of essential oils from different parts of Daphne mucronata Royle

Ashraf I, Zubair M, Rizwan K, Rasool N, Jamil M, Khan SA, et al.

Chem Cent J, 2018 Dec 17;12(1):135.
PMID: 30556121 DOI: 10.1186/s13065-018-0495-1

This research work was executed to determine chemical composition, anti-oxidant and anti-microbial potential of the essential oils extracted from the leaves and stem of Daphne mucronata Royle. From leaves and stem oils fifty-one different constituents were identified through GC/MS examination. The antioxidant potential evaluated through DPPH free radical scavenging activity and %-inhibition of peroxidation in linoleic acid system. The stem's essential oil showed the good antioxidant activity as compared to leaves essential oil. Results of Antimicrobial activity revealed that both stem and leaves oils showed strong activity against Candida albicans with large inhibition zone (22.2 ± 0.01, 18.9 ± 0.20 mm) and lowest MIC values (0.98 ± 0.005, 2.44 ± 0.002 mg/mL) respectively. Leaves essential was also active against Escherichia coli with inhibition zone of 8.88 ± 0.01 mm and MIC values of 11.2 ± 0.40 mg/mL. These results suggested that the plant's essential oils would be a potential cradle for the natural product based antimicrobial as well as antioxidant agents.
Fulltext Facile synthesis of N- (4-bromophenyl)-1- (3-bromothiophen-2-yl)methanimine derivatives via Suzuki cross-coupling reaction: their characterization and DFT studies

Rizwan K, Rasool N, Rehman R, Mahmood T, Ayub K, Rasheed T, et al.

Chem Cent J, 2018 Jul 17;12(1):84.
PMID: 30019193 DOI: 10.1186/s13065-018-0451-0

A variety of imine derivatives have been synthesized via Suzuki cross coupling of N-(4-bromophenyl)-1-(3-bromothiophen-2-yl)methanimine with various arylboronic acids in moderate to good yields (58-72%). A wide range of electron donating and withdrawing functional groups were well tolerated in reaction conditions. To explore the structural properties, Density functional theory (DFT) investigations on all synthesized molecules (3a-3i) were performed. Conceptual DFT reactivity descriptors and molecular electrostatic potential analyses were performed by using B3LYP/6-31G(d,p) method to explore the reactivity and reacting sites of all derivatives (3a-3i).
Exploring the factors and barriers of healthcare professionals in tertiary care hospitals towards pharmacovigilance: a multicenter study from Khyber Pakhtunkhwa, Pakistan

Sharif MJH, Farrukh MJ, Khan FU, Khan Q, Ahmed SS, Kousar R, et al.

Curr Med Res Opin, 2022 Feb 15.
PMID: 35166143 DOI: 10.1080/03007995.2022.2042992

BACKGROUND: Spontaneous Adverse drug reactions (ADRs) reporting is a cornerstone for a successful pharmacovigilance program as under-reporting of ADRs remains a major issue around the globe. The current study aimed to assess the knowledge attitude and practices of health care professionals regarding pharmacovigilance along with barriers and factors to encourage ADR reporting at tertiary care hospitals of Khyber-Pakhtunkhwa, Pakistan.
METHODS: A questionnaire-based cross-sectional survey was conducted, using the convenience sampling method to collect the data from doctors, nurses, and pharmacists working in seven tertiary care hospitals from seven districts of Khyber-Pakhtunkhwa province, Pakistan, between July 2019 and March 2020.
RESULTS: During the study, a total of 830 questionnaires were distributed, out of which 669 were returned (response rate 80.6%). Overall, Healthcare professionals exhibited poor knowledge (79.5%) about ADR reporting and pharmacovigilance however, 73.5% of pharmacists were more knowledgeable as compared to 18.7% doctors and 13.8% nurses (p < 0.001). Moreover, poor reporting practices were displayed by 95.6% doctors, 94.4% nurses 94.4% and 75.5% pharmacists (p < 0.001). However, the majority of healthcare professionals showed an overall positive attitude (94%) towards ADR reporting. The most frequently cited barriers were unavailability of reporting forms (92.5%), absence of a professional environment to discuss ADRs (82.5%), and lack of training (81.8%) whereas, most common factors to encourage ADR reporting were obligatory reporting (85.9%) and provision of ADR management guidelines and training (84.3%). A significant relation was found between the healthcare professionals and their professional status with the overall knowledge, attitude, and practice (KAP) scores (p
Fulltext First-principles calculations to investigate structural, electronic, elastic and optical properties of radium based cubic fluoro-perovskite materials

Shahzad MK, Hussain S, Farooq MU, Laghari RA, Bilal MH, Khan SA, et al.

Heliyon, 2023 Feb;9(2):e13687.
PMID: 36873152 DOI: 10.1016/j.heliyon.2023.e13687

Perovskite materials play a vital role in the field of material science via experimental as well as theoretical calculations. Radium semiconductor materials are considered the backbone of medical fields. These materials are considered in high technological fields to be used as controlling the decay ability. In this study, radium-based cubic fluoro-perovskite XRaF3 (where X = Rb and Na) are calculated using a DFT (density functional theory). These compounds are cubic nature with 221 space groups that construct on CASTEP (Cambridge-serial-total-energy-package) software with ultra-soft PPPW (pseudo-potential plane-wave) and GGA (Generalized-Gradient-approximation)-PBE (Perdew-Burke-Ernzerhof) exchange-correlation functional. The structural, optical, electronic, and mechanical properties of the compounds are calculated. According to the structural properties, NaRaF3 and RbRaF3 have a direct bandgap with 3.10eV and 4.187eV of NaRaF3 and RbRaF3, respectively. Total density of states (DOS) and partial density of states (PDOS) provide confirmation to the degree of electrons localized in distinct bands. NaRaF3 material is semiconductors and RbRaF3 is insulator, according to electronic results. The imaginary element dispersion of the dielectric function reveals its wide variety of energy transparency. In both compounds, the optical transitions are examined by fitting the damping ratio for the notional dielectric function scaling to the appropriate peaks. The absorption and the conductivity of NaRaF3 compound is better than the RbRaF3 compound which make it suitable for the solar cell applications increasing the efficiency and work function. We observed that both compounds are mechanically stable with cubic structure. The criteria for the mechanical stability of compounds are also met by the estimated elastic results. These compounds have potential application in field of solar cell and medical.
OBJECTIVES: The band gap, absorption and the conductivity are necessary conditions for potential applications. Here, literature was reviewed to check computational translational insight into the relationships between absorption and conductivity for solar cell and medical applications of novel RbRaF3 and NaRaF3 compounds.
Fulltext Overview of Early ChatGPT's Presence in Medical Literature: Insights From a Hybrid Literature Review by ChatGPT and Human Experts

Temsah O, Khan SA, Chaiah Y, Senjab A, Alhasan K, Jamal A, et al.

Cureus, 2023 Apr;15(4):e37281.
PMID: 37038381 DOI: 10.7759/cureus.37281

ChatGPT, an artificial intelligence chatbot, has rapidly gained prominence in various domains, including medical education and healthcare literature. This hybrid narrative review, conducted collaboratively by human authors and ChatGPT, aims to summarize and synthesize the current knowledge of ChatGPT in the indexed medical literature during its initial four months. A search strategy was employed in PubMed and EuropePMC databases, yielding 65 and 110 papers, respectively. These papers focused on ChatGPT's impact on medical education, scientific research, medical writing, ethical considerations, diagnostic decision-making, automation potential, and criticisms. The findings indicate a growing body of literature on ChatGPT's applications and implications in healthcare, highlighting the need for further research to assess its effectiveness and ethical concerns.
Fulltext Harnessing Machine Learning in Early COVID-19 Detection and Prognosis: A Comprehensive Systematic Review

Dabbagh R, Jamal A, Bhuiyan Masud JH, Titi MA, Amer YS, Khayat A, et al.

Cureus, 2023 May;15(5):e38373.
PMID: 37265897 DOI: 10.7759/cureus.38373

During the early phase of the COVID-19 pandemic, reverse transcriptase-polymerase chain reaction (RT-PCR) testing faced limitations, prompting the exploration of machine learning (ML) alternatives for diagnosis and prognosis. Providing a comprehensive appraisal of such decision support systems and their use in COVID-19 management can aid the medical community in making informed decisions during the risk assessment of their patients, especially in low-resource settings. Therefore, the objective of this study was to systematically review the studies that predicted the diagnosis of COVID-19 or the severity of the disease using ML. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA), we conducted a literature search of MEDLINE (OVID), Scopus, EMBASE, and IEEE Xplore from January 1 to June 31, 2020. The outcomes were COVID-19 diagnosis or prognostic measures such as death, need for mechanical ventilation, admission, and acute respiratory distress syndrome. We included peer-reviewed observational studies, clinical trials, research letters, case series, and reports. We extracted data about the study's country, setting, sample size, data source, dataset, diagnostic or prognostic outcomes, prediction measures, type of ML model, and measures of diagnostic accuracy. Bias was assessed using the Prediction model Risk Of Bias ASsessment Tool (PROBAST). This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO), with the number CRD42020197109. The final records included for data extraction were 66. Forty-three (64%) studies used secondary data. The majority of studies were from Chinese authors (30%). Most of the literature (79%) relied on chest imaging for prediction, while the remainder used various laboratory indicators, including hematological, biochemical, and immunological markers. Thirteen studies explored predicting COVID-19 severity, while the rest predicted diagnosis. Seventy percent of the articles used deep learning models, while 30% used traditional ML algorithms. Most studies reported high sensitivity, specificity, and accuracy for the ML models (exceeding 90%). The overall concern about the risk of bias was "unclear" in 56% of the studies. This was mainly due to concerns about selection bias. ML may help identify COVID-19 patients in the early phase of the pandemic, particularly in the context of chest imaging. Although these studies reflect that these ML models exhibit high accuracy, the novelty of these models and the biases in dataset selection make using them as a replacement for the clinicians' cognitive decision-making questionable. Continued research is needed to enhance the robustness and reliability of ML systems in COVID-19 diagnosis and prognosis.
Fulltext Impact of Cobalt Doping on the Structural, Optical, and Dielectric Properties of MgAl2O4 Spinel Material

Ullah K, Khan SA, Zaman A, Sarker MR, Ali A, Tirth V, et al.

ACS Omega, 2023 Aug 22;8(33):29959-29965.
PMID: 37636967 DOI: 10.1021/acsomega.3c00541

Nanomaterials (NMs) with structural, optical, and dielectric properties are called functional or smart materials and have favorable applications in various fields of material science and nanotechnology. Pure and Co-doped MgAl2O4 were synthesized by using the sol-gel combustion method. A systematic investigation was carried out to understand the effects of the Co concentration on the crystalline phase, morphology, and optical and dielectric properties of Co-doped MgAl2O4. X-ray diffraction confirmed the cubic spinel structure with the Fd3̅m space group, and there was no impurity phase, while the surface morphology of the samples was investigated by scanning electron microscopy. The dielectric properties of the synthesized material are investigated using an LCR meter with respect to the variation in frequency (1-2 GHz), and their elemental composition has been examined through the energy-dispersive X-ray technique. The existence of the metal-oxygen Mg-Al-O bond has been confirmed by Fourier transform infrared spectroscopy. The value of the dielectric constant decreases with the increasing frequency and Co concentration. The optical behaviors of the Co2+-doped MgAl2O4 reveal that the optical properties were enhanced by increasing the cobalt concentration, which ultimately led to a narrower band gap, which make them exquisite and suitable for energy storage applications, especially for super capacitors. This work aims to focus on the effect of cobalt ions in different concentrations on structural, optical, and dielectric properties.
Fulltext Unusual multiple production of N-acylhomoserine lactones a by Burkholderia sp. strain C10B isolated from dentine caries

Goh SY, Tan WS, Khan SA, Chew HP, Abu Kasim NH, Yin WF, et al.

Sensors (Basel), 2014;14(5):8940-9.
PMID: 24854358 DOI: 10.3390/s140508940

Bacteria realize the ability to communicate by production of quorum sensing (QS) molecules called autoinducers, which regulate the physiological activities in their ecological niches. The oral cavity could be a potential area for the presence of QS bacteria. In this study, we report the isolation of a QS bacterial isolate C10B from dentine caries. Preliminary screening using Chromobacterium violaceum CV026 biosensor showed that isolate C10B was able to produce N-acylhomoserine lactones (AHLs). This bacterium was further identified as a member of Burkholderia, an opportunistic pathogen. The isolated Burkholderia sp. was confirmed to produce N-hexanoyl-L-homoserine lactone (C6-HSL), N-octanoyl-L-homoserine lactone (C8-HSL), N-decanoyl-L-homoserine lactone (C10-HSL) and N-dodecanoyl-L-homoserine lactone (C12-HSL).
Renal denervation restores the baroreflex control of renal sympathetic nerve activity and heart rate in Wistar-Kyoto rats with cisplatin-induced renal failure

Khan SA, Sattar MA, Rathore HA, Abdulla MH, Ud Din Ahmad F, Ahmad A, et al.

Acta Physiol (Oxf), 2014 Mar;210(3):690-700.
PMID: 24438102 DOI: 10.1111/apha.12237

There is evidence that in chronic renal failure, the sympathetic nervous system is activated. This study investigated the role of the renal innervation in suppressing high- and low-pressure baroreflex control of renal sympathetic nerve activity and heart rate in cisplatin-induced renal failure.
Fulltext Cystathione gamma lyase/Hydrogen Sulphide Pathway Up Regulation Enhances the Responsiveness of α1A and α1B-Adrenoreceptors in the Kidney of Rats with Left Ventricular Hypertrophy

Ahmad A, Sattar MA, Azam M, Abdulla MH, Khan SA, Hashmi F, et al.

PLoS One, 2016;11(5):e0154995.
PMID: 27191852 DOI: 10.1371/journal.pone.0154995

The purpose of the present study was to investigate the interaction between H2S and NO (nitric oxide) in the kidney and to evaluate its impact on the functional contribution of α1A and α1B-adrenoreceptors subtypes mediating the renal vasoconstriction in the kidney of rats with left ventricular hypertrophy (LVH). In rats the LVH induction was by isoprenaline administration and caffeine in the drinking water together with intraperitoneal administration of H2S. The responsiveness of α1A and α1B to exogenous noradrenaline, phenylephrine and methoxaminein the absence and presence of 5-methylurapidil (5-MeU) and chloroethylclonidine (CEC) was studied. Cystathione gamma lyase (CSE), cystathione β synthase (CBS), 3-mercaptopyruvate sulphar transferase (3-MST) and endothelial nitric oxide synthase (eNOS) were quantified. There was significant up regulation of CSE and eNOS in the LVH-H2S compared to the LVH group (P<0.05). Baseline renal cortical blood perfusion (RCBP) was increased (P<0.05) in the LVH-H2S compared to the LVH group. The responsiveness of α1A-adrenergic receptors to adrenergic agonists was increased (P<0.05) after administration of low dose 5-Methylurapidil in the LVH-H2S group while α1B-adrenergic receptors responsiveness to adrenergic agonists were increased (P<0.05) by both low and high dose chloroethylclonidine in the LVH-H2S group. Treatment of LVH with H2S resulted in up-regulation of CSE/H2S, CBS, and 3-MST and eNOS/NO/cGMP pathways in the kidney. These up regulation of CSE/H2S, CBS, and 3-MST and eNOS/NO/cGMP pathways enhanced the responsiveness of α1A and α1B-adrenoreceptors subtypes to adrenergic agonists in LVH-H2S. These findings indicate an important role for H2S in modulating deranged signalling in the renal vasculature resulting from LVH development.
Functional contribution of α1D-adrenoceptors in the renal vasculature of left ventricular hypertrophy induced with isoprenaline and caffeine in Wistar-Kyoto rats

Ahmad A, Sattar MA, Rathore HA, Abdulla MH, Khan SA, Abdullah NA, et al.

Can J Physiol Pharmacol, 2014 Dec;92(12):1029-35.
PMID: 25403946 DOI: 10.1139/cjpp-2014-0236

This study investigated the role of α1D-adrenoceptor in the modulation of renal haemodynamics in rats with left ventricular hypertrophy (LVH). LVH was established in Wistar-Kyoto (WKY) rats with isoprenaline (5.0 mg · (kg body mass)(-1), by subcutaneous injection every 72 h) and caffeine (62 mg · L(-1) in drinking water, daily for 14 days). Renal vasoconstrictor responses were measured for noradrenaline (NA), phenylephrine (PE), and methoxamine (ME) before and immediately after low or high dose intrarenal infusions of BMY 7378, a selective α1D-adrenoceptor blocker. The rats with LVH had higher mean arterial blood pressure and circulating NA levels, but lower renal cortical blood perfusion compared with the control group (all P < 0.05). In the LVH group, the magnitude of the renal vasoconstrictor response to ME was blunted, but not the response to NA or PE (P < 0.05), compared with the control group (LVH vs. C, 38% vs. 50%). The magnitude of the drop in the vasoconstrictor responses to NA, PE, and ME in the presence of a higher dose of BMY 7378 was significantly greater in the LVH group compared with the control group (LVH vs. C, 45% vs. 25% for NA, 52% vs. 33% for PE, 66% vs. 53% for ME, all P < 0.05). These findings indicate an impaired renal vasoconstrictor response to adrenergic agonists during LVH. In addition, the α1D-adrenoceptor subtype plays a key role in the modulation of vascular responses in this diseased state.
Fulltext Determination of Non-Recrystallization Temperature for Niobium Microalloyed Steel

Akhtar MN, Khan M, Khan SA, Afzal A, Subbiah R, Ahmad SN, et al.

Materials (Basel), 2021 May 18;14(10).
PMID: 34070060 DOI: 10.3390/ma14102639

In the present investigation, the non-recrystallization temperature (TNR) of niobium-microalloyed steel is determined to plan rolling schedules for obtaining the desired properties of steel. The value of TNR is based on both alloying elements and deformation parameters. In the literature, TNR equations have been developed and utilized. However, each equation has certain limitations which constrain its applicability. This study was completed using laboratory-grade low-carbon Nb-microalloyed steels designed to meet the API X-70 specification. Nb- microalloyed steel is processed by the melting and casting process, and the composition is found by optical emission spectroscopy (OES). Multiple-hit deformation tests were carried out on a Gleeble® 3500 system in the standard pocket-jaw configuration to determine TNR. Cuboidal specimens (10 (L) × 20 (W) × 20 (T) mm3) were taken for compression test (multiple-hit deformation tests) in gleeble. Microstructure evolutions were carried out by using OM (optical microscopy) and SEM (scanning electron microscopy). The value of TNR determined for 0.1 wt.% niobium bearing microalloyed steel is ~ 951 °C. Nb- microalloyed steel rolled at TNR produce partially recrystallized grain with ferrite nucleation. Hence, to verify the TNR value, a rolling process is applied with the finishing rolling temperature near TNR (~951 °C). The microstructure is also revealed in the pancake shape, which confirms TNR.
Fulltext Enhancement in Cathodic Redox Reactions of Single-Chambered Microbial Fuel Cells with Castor Oil-Emitted Powder as Cathode Material

Kumbar SS, Jadhav DA, Jarali CS, Talange DB, Afzal A, Khan SA, et al.

Materials (Basel), 2021 Aug 09;14(16).
PMID: 34442980 DOI: 10.3390/ma14164454

Microbial fuel cell (MFC) would be a standalone solution for clean, sustainable energy and rural electrification. It can be used in addition to wastewater treatment for bioelectricity generation. Materials chosen for the membrane and electrodes are of low cost with suitable conducting ions and electrical properties. The prime objective of the present work is to enhance redox reactions by using novel and low-cost cathode catalysts synthesized from waste castor oil. Synthesized graphene has been used as an anode, castor oil-emitted carbon powder serves as a cathode, and clay material acts as a membrane. Three single-chambered MFC modules developed were used in the current study, and continuous readings were recorded. The maximum voltage achieved was 0.36 V for a 100 mL mixture of domestic wastewater and cow dung for an anodic chamber of 200 mL. The maximum power density obtained was 7280 mW/m2. In addition, a performance test was evaluated for another MFC with inoculums slurry, and a maximum voltage of 0.78 V and power density of 34.4093 mW/m2 with an anodic chamber of 50 mL was reported. The present study's findings show that such cathode catalysts can be a suitable option for practical applications of microbial fuel cells.
Hazardous heavy metals contamination of vegetables and food chain: Role of sustainable remediation approaches - A review

Kumar S, Prasad S, Yadav KK, Shrivastava M, Gupta N, Nagar S, et al.

Environ Res, 2019 12;179(Pt A):108792.
PMID: 31610391 DOI: 10.1016/j.envres.2019.108792

This review emphasizes the role of toxic metal remediation approaches due to their broad sustainability and applicability. The rapid developmental processes can incorporate a large quantity of hazardous and unseen heavy metals in all the segments of the environment, including soil, water, air and plants. The released hazardous heavy metals (HHMs) entered into the food chain and biomagnified into living beings via food and vegetable consumption and originate potentially health-threatening effects. The physical and chemical remediation approaches are restricted and localized and, mainly applied to wastewater and soils and not the plant. The nanotechnological, biotechnological and genetical approaches required to more rectification and sustainability. A cellular, molecular and nano-level understanding of the pathways and reactions are responsible for potentially toxic metals (TMs) accumulation. These approaches can enable the development of crop varieties with highly reduced concentrations of TMs in their consumable foods and vegetables. As a critical analysis by authors observed that nanoparticles could provide very high adaptability for both in-situ and ex-situ remediation of hazardous heavy metals (HHMs) in the environment. These methods could be used for the improvement of the inbuilt genetic potential and phytoremediation ability of plants by developing transgenic. These biological processes involve the transfer of gene of interest, which plays a role in hazardous metal uptake, transport, stabilization, inactivation and accumulation to increased host tolerance. This review identified that use of nanoremediation and combined biotechnological and, transgenic could help to enhance phytoremediation efficiency in a sustainable way.
Effect of gasotransmitters treatment on expression of hypertension, vascular and cardiac remodeling and hypertensive nephropathy genes in left ventricular hypertrophy

Ahmad A, Riaz Z, Sattar MA, Khan SA, John EJ, Rashid S, et al.

Gene, 2020 May 05;737:144479.
PMID: 32068124 DOI: 10.1016/j.gene.2020.144479

BACKGROUND: Cardiac and renal dysfunction are often co-morbid pathologies leading to worsening prognosis resulting in difficulty in therapy of left ventricular hypertrophy (LVH). The aim of the current study was to determine the changes in expression of human ortholog genes of hypertension, vascular and cardiac remodeling and hypertensive nephropathy phenotypes under normal, disease and upon treatment with gasotransmitter including H2S (hydrogen sulphide), NO (nitric oxide) and combined (H2S + NO).
METHODS: A total of 72 Wistar Kyoto rats (with equivalent male and female animals) were recruited in the present study where LVH rat models were treated with H2S and NO individually as well as with both combined. Cardiac and renal physical indices were recorded and relative gene expression were quantified.
RESULTS: Both cardiac and renal physical indices were significantly modified with individual as well as combined H2S + NO treatment in control and LVH rats. Expression analysis revealed, hypertension, vascular remodeling genes ACE, TNFα and IGF1, mRNAs to be significantly higher (P ≤ 0.05) in the myocardia and renal tissues of LVH rats, while individual and combined H2S + NO treatment resulted in lowering the gene expression to normal/near to normal levels. The cardiac remodeling genes MYH7, TGFβ, SMAD4 and BRG1 expression were significantly up-regulated (P ≤ 0.05) in the myocardia of LVH where the combined H2S + NO treatment resulted in normal/near to normal expression more effectively as compared to individual treatments. In addition individual as well as combined H2S and NO treatment significantly decreased PKD1 expression in renal tissue, which was up-regulated in LVH rats (P ≤ 0.05).
CONCLUSIONS: The reduction in hemodynamic parameters and cardiac indices as well as alteration in gene expression on treatment of LVH rat model indicates important therapeutic potential of combined treatment with H2S + NO gasotransmitters in hypertension and cardiac hypertrophy when present as co-morbidity with renal complications.
Fulltext Heat Transfer Characteristics of Fullerene and Titania Nanotube Nanofluids under Agitated Quench Conditions

Dennis Quadros J, Khan SA, T P, Iqbal Mogul Y, R H, Abbas M, et al.

ACS Omega, 2022 Dec 27;7(51):47764-47783.
PMID: 36591137 DOI: 10.1021/acsomega.2c05397

Distilled water and aqueous fullerene nanofluids having concentrations of 0.02, 0.2, and 0.4 vol % and titania (titanium dioxide, TiO2) nanofluids of 0.0002, 0.002, and 0.02 vol % were analyzed for heat transfer characteristics. Quenching mediums were stirred at impeller speeds of 0, 500, 1,000, and 1,500 RPMs in a typical Tensi agitation system. During the quenching process, a metal probe made of ISO 9950 Inconel was used to record the temperature history. The inverse heat conduction method was used to calculate the spatial and temporal heat flux. The nanofluid rewetting properties were measured and matched to those of distilled water. The maximum mean heat flux was 3.26 MW/m2, and the quickest heat extraction was 0.2 vol % fullerene nanofluid, according to the results of the heat transfer investigation.
Lignin nanoparticles-reduced graphene oxide based hydrogel: A novel strategy for environmental applications

Sohni S, Hassan T, Khan SB, Akhtar K, Bakhsh EM, Hashim R, et al.

Int J Biol Macromol, 2023 Jan 15;225:1426-1436.
PMID: 36436599 DOI: 10.1016/j.ijbiomac.2022.11.200

In this work, facile fabrication of lignin nanoparticles (LNP)-based three-dimensional reduced graphene oxide hydrogel (rGO@LNP) has been demonstrated as a novel strategy for environmental applications. Herein, LNP were facilely synthesized from walnut shell waste through a direct chemical route. These LNP were incorporated into the continuous porous network of rGO network to fabricate rGO@LNP hydrogel. Characterization studies were carried out using various analytical techniques viz. scanning electron microscopy, Fourier transform IR spectroscopy, X-ray diffraction and thermogravimetric analysis. The efficiency of rGO@LNP hydrogel as adsorptive platform was evaluated by employing methylene blue and Pb2+ as model pollutants, whilst the effect of various experimental parameters was ascertained for optimal performance. Furthermore, Agar well diffusion method was used to check the antibacterial activities of the hydrogel using two bacterial pathogenic strains, i.e. Klebsiella pneumoniae (gram negative) and Enterococcus faecalis (gram positive). Results showed that after the inclusion of LNP into rGO hydrogel, there was a marked improvement in pollutant's uptake ability and compared to bare LNP and rGO, the composite hydrogel showed enhanced bactericidal effect. Overall, this approach is outstanding because of the synergy of functional properties of nano-lignin and rGO due to multi-interaction sites in the resulting hydrogel. The results presented herein support the application of rGO@LNP as innovative water filter material for scavenging broad spectrum pollutants and bactericidal properties.
Fulltext Performance and Emission Analysis of Biodiesel Blends in a Low Heat Rejection Engine with an Antioxidant Additive: An Experimental Study

Venkatesan EP, Rajendran S, Murugan M, Medapati SR, Ramachandra Murthy KVS, Alwetaishi M, et al.

ACS Omega, 2023 Oct 10;8(40):36686-36699.
PMID: 37841135 DOI: 10.1021/acsomega.3c02742

The rapid depletion of crude oil and environmental degradation necessitate the search for alternative fuel sources for internal combustion engines. Biodiesel is a promising alternative fuel for compression ignition (CI) engines due to its heat content and combustion properties. Biodiesel blends are used in various vehicles and equipment, such as cars, trucks, buses, off-road vehicles, and oil furnaces. Biodiesel can reduce emissions from CI engines by up to 75% and improve engine durability due to its high lubricity. However, biodiesel has some drawbacks, including a performance reduction and increased nitrogen oxide emissions. Therefore, this study aims to investigate using environmentally available biodiesel in a low-heat rejection engine and an antioxidant additive to enhance the performance and reduce nitrogen oxide emissions. India currently has several biodiesel sources, including mango seed oil, mahua oil, and pongamia oil, which can be effectively utilized in CI engines by adding l-ascorbic acid. The experimental work involves a single-cylinder 4-stroke water-cooled direct injection CI engine with a power output of 5.2 kW. The engine's cylinder head, piston head, and valves are coated with lanthanum oxide using the plasma spray coating technique, with a thickness of 0.5 mm. The coated and uncoated engines are tested with different proportions of mahua oil, mango seed oil, and pongamia oil. The results show that the engine's performance is significantly improved compared to the baseline engine at all loads. Additionally, these biodiesels exhibit a notable reduction in nitrogen oxide emissions when combined with l-ascorbic acid.
Patients' Readiness Towards Teledentistry in the Malaysian Urban Population Attending an Undergraduate Teaching University

Zain E, Rahman N, Khan SA, Farook MS, Khan E, Jubapu AS, et al.

Telemed J E Health, 2024 Jan;30(1):214-222.
PMID: 37358591 DOI: 10.1089/tmj.2023.0075

Introduction: COVID-19 disease has resulted in suspension of all nonurgent routine dental treatments. In view of COVID-19 situation, social distancing, movement restriction orders, and affected health care systems, there is an urgent need to resume and deliver oral health care remotely. Hence, alternative means of dental care should be available for both patients and dentists. Therefore, this study aims to assess patients' readiness for teledentistry in Malaysian urban population attending an undergraduate teaching university. Methods: A cross-sectional study was conducted among 631 adult patients visiting the Faculty of Dentistry, SEGi University, from January 2020 to May 2021 in Selangor, Malaysia. A validated, self-administered, 5-point Likert scale online questionnaire comprising five domains was administered. (1) Patients' demographics and dental history, (2) patients' access to teledentistry, (3) patients' understanding towards teledentistry, (4) patients' willingness, and (5) barriers in using teledentistry were used to collect the required information. Results: Six hundred and thirty-one (n = 631) participants responded to the questionnaire. Ninety percent of patients were able to connect to Wi-Fi services independently and 77% participants were comfortable using online communication platforms. Seventy-one percent of the participants agreed that video and telephone clinics can reduce chances of infection rather than face-to-face consultation during the pandemic. Fifty-five percent of patients felt that virtual clinics would save time and 60% thought it could reduce travelling costs. Fifty-one percent showed their willingness to use video or telephone clinics when implemented at onsite clinics. Conclusion: Our study shows the readiness of patients to accept teledentistry as an alternative method of oral care if appropriate training and education are provided. The results of this study have prompted an increase in patients' education and shown a need to train clinicians and patients to integrate this technology at SEGi University. This might facilitate unhindered dental consultation and care in all situations.
Fulltext Up Regulation of cystathione γ lyase and Hydrogen Sulphide in the Myocardium Inhibits the Progression of Isoproterenol-Caffeine Induced Left Ventricular Hypertrophy in Wistar Kyoto Rats

Ahmad A, Sattar MA, Rathore HA, Abdulla MH, Khan SA, Azam M, et al.

PLoS One, 2016;11(3):e0150137.
PMID: 26963622 DOI: 10.1371/journal.pone.0150137

Hydrogen sulphide (H2S) is an emerging molecule in many cardiovascular complications but its role in left ventricular hypertrophy (LVH) is unknown. The present study explored the effect of exogenous H2S administration in the regression of LVH by modulating oxidative stress, arterial stiffness and expression of cystathione γ lyase (CSE) in the myocardium. Animals were divided into four groups: Control, LVH, Control-H2S and LVH-H2S. LVH was induced by administering isoprenaline (5mg/kg, every 72 hours, S/C) and caffeine in drinking water (62mg/L) for 2 weeks. Intraperitoneal NaHS, 56μM/kg/day for 5 weeks, was given as an H2S donor. Myocardial expression of Cystathione γ lyase (CSE) mRNA was quantified using real time polymerase chain reaction (qPCR).There was a 3 fold reduction in the expression of myocardial CSE mRNA in LVH but it was up regulated by 7 and 4 fold in the Control-H2S and LVH-H2S myocardium, respectively. Systolic blood pressure, mean arterial pressure, pulse wave velocity were reduced (all P<0.05) in LVH-H2S when compared to the LVH group. Heart, LV weight, myocardial thickness were reduced while LV internal diameter was increased (all P<0.05) in the LVH-H2S when compared to the LVH group. Exogenous administration of H2S in LVH increased superoxide dismutase, glutathione and total antioxidant capacity but significantly reduced (all P<0.05) plasma malanodialdehyde in the LVH-H2S compared to the LVH group. The renal cortical blood perfusion increased by 40% in LVH-H2S as compared to the LVH group. Exogenous administration of H2S suppressed the progression of LVH which was associated with an up regulation of myocardial CSE mRNA/ H2S and a reduction in pulse wave velocity with a blunting of systemic hemodynamic. This CSE/H2S pathway exhibits an antihypertrophic role by antagonizing the hypertrophic actions of angiotensin II(Ang II) and noradrenaline (NA) but attenuates oxidative stress and improves pulse wave velocity which helps to suppress LVH. Exogenous administration of H2S augmented the reduced renal cortical blood perfusion in the LVH state.

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