Effects of targeted remediation in anatomy for first year medical students

Nachiket Shankar,Nachiket Shankar,Yogitha Ravindranath,Roopa Ravindranath,Henal Shah 대한해부학회 2019 Anatomy & Cell Biology Vol.52 No.1

The aim of this study was to assess the effectiveness of a questionnaire to guide targeted remediation among undergraduate medical students in anatomy. Seventy-five students from a medical college in South India who failed in the first internal theory examination were administered a validated 35-item questionnaire. The total and domain specific questionnaire scores were calculated. Specific weekly interventions for each student based on the questionnaire scores were conducted by appointed academic mentors for three months prior to the second internal examination. The dependent variable was performance in the second internal examination. The students were re-administered the questionnaire after the second internal examination. The independent variables were the marks obtained in the first internal examination, domain specific and total questionnaire scores, sex, and regularity of the student in attending the remedial sessions. Inferential statistical tests used were the chi-square test, independent sample t test, paired t test, multiple regression and binomial logistic regression. Of the 75 students who underwent remediation, 54 (72%) passed in the second internal examination. The scores in the second internal examination among these students was found to be significantly higher as compared to the first internal examination. The total, subject related and study skills questionnaire score were significantly lower after remediation. Students who were irregular had a significantly lower pass rate. The multivariate analysis showed that only the first internal marks added significantly to the prediction about second internal performance. This study provides evidence to show that struggling students perceive a benefit from targeted remediation.

Antimicrobial wrapping paper coated with a ternary blend of carbohydrates (alginate, carboxymethyl cellulose, carrageenan) and grapefruit seed extract

Shankar, Shiv,Rhim, Jong-Whan Elsevier 2018 Carbohydrate Polymers Vol.196 No.-

<P><B>Abstract</B></P> <P>A functional biopolymer-coated paper was prepared by coating a ternary blend of the alginate, carboxymethyl cellulose, and carrageenan with grapefruit seed extract (GSE) for the substitute use of synthetic polymer-coated paper. The microstructure of the surface and cross-section of the coated paper analyzed by field emission scanning electron microscope (FE-SEM) indicated that the biopolymer was compatible with the base paper and filled the pores of the porous fiber to make a smooth-surfaced coating paper. The properties of the biopolymer-coated paper, such as water and oil resistance, water vapor barrier, surface hydrophobicity, and mechanical properties, increased significantly compared with not only the base paper but also commercially used PE-coated paper. The blended biopolymer coating material exhibited strong antibacterial activity against food-borne pathogenic bacteria, <I>Listeria monocytogenes</I> and <I>Escherichia coli</I>, which were destroyed completely within 3 and 9 h, respectively. The packaging test for a minced fish cake packed with the biopolymer-coated paper showed the complete destruction of surface inoculated bacteria in 6–9 days. The biopolymer-coated paper showed a high potential for disposable food packaging applications to increase the shelf-life of packaged food.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A ternary blend of the alginate, carboxymethyl cellulose, and carrageenan with grapefruit seed extract (GSE) was used for coating of paper. </LI> <LI> Water and oil resistance properties of paper increased after coating. </LI> <LI> Water vapor barrier, surface hydrophobicity, and mechanical properties, increased significantly after coating. </LI> <LI> Blended biopolymer coating material exhibited strong antibacterial activity. </LI> <LI> The biopolymer-coated paper showed a high potential for disposable food packaging applications. </LI> </UL> </P>

Design and Analysis of a Low-Vibration Cryogenic Dewar Module for Optical Testing of Infrared Detectors

Shankar Bhattarai,Youngsoo Jo,Hoyeon Yang,Seungcheol Bang,Woong-Seob Jeong 한국천문학회 2023 天文學會報 Vol.48 No.2

Preparation and properties of carbohydrate-based composite films incorporated with CuO nanoparticles

Shankar, Shiv,Wang, Long-Feng,Rhim, Jong-Whan Applied Science Publishers 2017 Carbohydrate Polymers Vol.169 No.-

<P><B>Abstract</B></P> <P>The present study aimed to develop the carbohydrate biopolymer based antimicrobial films for food packaging application. The nanocomposite films of various biopolymers and copper oxide nanoparticles (CuONPs) were prepared by solvent casting method. The nanocomposite films were characterized using SEM, FTIR, XRD, and UV–vis spectroscopy. The thermal stability, UV barrier, water vapor permeability, and antibacterial activity of the composite films were also evaluated. The surface morphology of the films was dependent on the types of polymers used. The XRD revealed the crystallinity of CuONPs in the composite films. The addition of CuONPs increased the thickness, tensile strength, UV barrier property, relative humidity, and water vapor barrier property. The CuONPs incorporated composite films exhibited strong antibacterial activity against <I>Escherichia coli</I> and <I>Listeria monocytogenes</I>. The developed composite films could be used as a UV-light barrier antibacterial films for active food packaging.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanocomposite films of biopolymers and CuO nanoparticles were prepared. </LI> <LI> Mechanical, UV barrier, and water vapor barrier properties increased. </LI> <LI> Different biopolymer interacted with CuO nanoparticles differently. </LI> <LI> CuO nanoparticles incorporated films exhibited strong antibacterial activity. </LI> </UL> </P>

Preparation of antibacterial poly(lactide)/poly(butylene adipate-<i>co</i>-terephthalate) composite films incorporated with grapefruit seed extract

Shankar, Shiv,Rhim, Jong-Whan Elsevier 2018 INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES Vol.120 No.1

<P><B>Abstract</B></P> <P>Antimicrobial poly(lactide) (PLA)/poly(butylene adipate-<I>co</I>-terephthalate) (PBAT) blend films incorporated with grapefruit seed extract (GSE) were prepared using a solvent casting method. Effect of GSE on the morphological, water vapor barrier, thermostability, color, optical, and antimicrobial properties of PLA/PBAT composite films was investigated. The composite films showed a yellowish tint after incorporation of GSE and exhibited a high UV-light barrier property. Incorporation of GSE increased the flexibility and tensile strength of the composite films. Films incorporated with 7 wt% of GSE exhibited potent antibacterial activity against <I>Listeria monocytogenes</I>, but they showed only bacteriostatic activity against <I>Escherichia coli</I>. The PLA/PBAT-GSE composite film with UV-light barrier and antibacterial properties has a high potential for an active food packaging application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PLA/PBAT blend film was prepared using a solvent casting method. </LI> <LI> Grapefruit seed extract was incorporated into the PLA/PBAT blend films. </LI> <LI> Incorporation of GSE increased mechanical and light barrier properties. </LI> <LI> The composite film showed strong antibacterial activity against <I>L. monocytogenes</I>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Incorporation of zinc oxide nanoparticles improved the mechanical, water vapor barrier, UV-light barrier, and antibacterial properties of PLA-based nanocomposite films

Shankar, Shiv,Wang, Long-Feng,Rhim, Jong-Whan Elsevier 2018 Materials science & engineering. C, Materials for Vol.93 No.-

<P><B>Abstract</B></P> <P>Zinc oxide nanoparticles (ZnO NPs) were synthesized using zinc chloride and NaOH and they were incorporated to prepare PLA/ZnO NPs composite films. The SEM images showed that the ZnO NPs were cubical in shape with size ranged from 50 to 100 nm, and the PLA/ZnO NPs composite films were smooth and compact. The composite films exhibited strong UV-light barrier property with a slight decrease in the transparency. The thickness, tensile strength, and water vapor barrier property of the films increased significantly after incorporation of ZnO NPs. The TS of PLA films increased by 37.5%, but the WVP decreased by 30.5% from 3.11 × 10<SUP>−11</SUP> to 2.16 × 10<SUP>−11</SUP> g m/m<SUP>2</SUP>·Pa·s when 0.5 wt% of ZnO NPs was incorporated. The composite films exhibited potent antibacterial activity against food-borne pathogenic bacteria, <I>Escherichia coli</I> and <I>Listeria monocytogenes.</I> The developed films were applied to the packaging of a minced fish paste and showed strong antibacterial function. The prepared composite films could be used as antibacterial and UV-light barrier films for food packaging and biomedical applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ZnO NPs were prepared using zinc chloride and NaOH. </LI> <LI> PLA/ZnO NPs composite films were prepared by a solvent casting method. </LI> <LI> PLA/ZnO NPs composite films exhibited strong antibacterial activity. </LI> <LI> PLA/ZnO NPs packaging increased the shelf-life of minced fish cake. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Preparation of sulfur nanoparticles and their antibacterial activity and cytotoxic effect

Shankar, Shiv,Pangeni, Rudra,Park, Jin Woo,Rhim, Jong-Whan Elsevier 2018 Materials Science and Engineering C Vol.92 No.-

<P><B>Abstract</B></P> <P>Sulfur nanoparticles (SNPs) were prepared using sodium thiosulfate and hydrochloric acid, and the UV–visible spectrum showed the formation of nanoparticulate sulfur. The SNPs were characterized by UV–visible spectrophotometer, transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The antibacterial activity and the cytotoxic effects of the SNPs on the human lung carcinoma (A549), mouse colon carcinoma (CT26), Caco-2, and human fibroblast (CCD-986sk) cells were tested. In addition, the inhibitory effect of the SNPs on the cancer cell migration was evaluated. The SNPs capped with chitosan (SNP2) exhibited strong antibacterial activity against <I>Escherichia coli</I> and <I>Staphylococcus aureus.</I> SNP2 also effectively inhibited the proliferation and migration of cancer cells with minimal toxic effect on normal cells. SNP2 therefore has potential for medical applications, including those used as antibacterial and chemotherapeutic agents.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Sulfur nanoparticles (SNPs) were prepared by sodium thiosulphate and hydrochloric acid. </LI> <LI> Chitosan and ultrasonication reduced the size of SNPs. </LI> <LI> SNPs capped with chitosan (SNP2) showed strong antibacterial activity. </LI> <LI> SNP2 exhibited strong cytotoxic activity and inhibitory effect on the cancer cell migration. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of Concentration of ZnO Nanoparticles on Mechanical, Optical, Thermal, and Antimicrobial Properties of Gelatin/ZnO Nanocomposite Films

Shankar, Shiv,Teng, Xinnan,Rhim, Jong-Whan Korea Society of Packaging Science and Technology 2014 한국포장학회지 Vol.20 No.2

This study illustrates the synthesis of gelatin based zinc oxide nanoparticle (ZnONPs) incorporated nanocomposite films using different concentrations of ZnONPs. The ZnONPs were oval in shape and the size ranged from 100- 200 nm. The nanocomposite films were characterized by UV-visible, FE-SEM, FT-IR, and XRD. The concentrations of ZnONPs greatly influenced the properties of nanocomposite films. The absorption peaks around 360 nm increased with the increasing concentrations of ZnONPs. The surface color of film did not change while transmittance at 280 nm was greatly reduced with increase in the concentration of ZnONPs. FTIR spectra showed the interaction of ZnONPs with gelatin. XRD data demonstrated the crystalline nature of ZnONPs. The thermostability, char content, water contact angle, water vapor permeability, moisture content, and elongation at break of nanocomposite films increased, whereas, tensile strength and modulus decreased with increase in the concentrations of ZnONPs. The gelatin/ZnONPs nanocomposite films showed profound antibacterial activity against both Gram-positive and Gram-negative food-borne pathogenic bacteria. The gelatin/$ZnONP^{1.5}$ nanocomposite film showed the best UV barrier and antimicrobial properties among the tested-films, which indicated a high potential for use as an active food packaging films with environmentally-friendly nature.

Evaluation of biochar-ultrafiltration membrane processes for humic acid removal under various hydrodynamic, pH, ionic strength, and pressure conditions

Shankar, Vaibhavi,Heo, Jiyong,Al-Hamadani, Yasir A.J.,Park, Chang Min,Chu, Kyoung Hoon,Yoon, Yeomin Academic Press 2017 Journal of Environmental Management Vol. No.

<P>The performance of an ultrafiltration (UF)-biochar process was evaluated in comparison with a UF membrane process for the removal of humic acid (HA). Bench-scale UF experiments were conducted to study the rejection and flux trends under various hydrodynamic, pH, ionic strength, and pressure conditions. The resistance-in-series model was used to evaluate the processes and it showed that unlike stirred conditions, where low fouling resistance was observed (28.7 x 10(12) m(-1) to 32.5 x 10(12) m(-1)), higher values and comparable trends were obtained for UF-biochar and UF alone for unstirred conditions (28.7 x 10(12) m(-1) to 32.5 x 10(12) m(-1)). Thus, the processes were further evaluated under unstirred conditions. Additionally, total fouling resistance was decreased in the presence of biochar by 6%, indicating that HA adsorption by biochar could diminish adsorption fouling on the UF membrane and thus improve the efficiency of the UF-biochar process. The rejection trends of UF-biochar and UF alone were similar in most cases, whereas UF-biochar showed a noticeable increase in flux of around 18-25% under various experimental conditions due to reduced membrane fouling. Three-cycle filtration tests further demonstrated that UF-biochar showed better membrane recovery and antifouling capability by showing more HA rejection (3-5%) than UF membrane alone with each subsequent cycle of filtration. As a result of these findings, the UF-biochar process may potentially prove be a viable treatment option for the removal of HA from water. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Aromatase Inhibition and Capecitabine Combination as 1^st or 2^nd Line Treatment for Metastatic Breast Cancer - a Retrospective Analysis

Shankar, Abhishek,Roy, Shubham,Rath, Goura Kishor,Julka, Pramod Kumar,Kamal, Vineet Kumar,Malik, Abhidha,Patil, Jaineet,Jeyaraj, Pamela Alice,Mahajan, Manmohan K Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.15

Background: Preclinical studies have shown that the combination of an aromatase inhibitor (AI) and capecitabine in estrogen receptor (ER)- positive cell lines enhance antitumor efficacy. This retrospective analysis of a group of patients with metastatic breast cancer (MBC) evaluated the efficacy and safety of combined AI with capecitabine. Materials and Methods: Patients with hormone receptor-positive metastatic breast cancer treated between 1st January 2005 and 31st December 2010 with a combination of capecitabine and AI were evaluated and outcomes were compared with those of women treated with capecitabine in conventional dose or AI as a monotherapy. Results: Of 72 patients evaluated, 31 received the combination treatment, 22 AI and 19 capecitabine. The combination was used in 20 patients as first-line and 11 as second-line treatment. Mean age was 46.2 years with a range of 28-72 years. At the time of progression, 97% had a performance status of <2 and 55% had visceral disease. No significant difference was observed between the three groups according to clinical and pathological features. Mean follow up was 38 months with a range of 16-66 months. The median PFS of first-line treatment was significantly better for the combination (PFS 21 months vs 8.0 months for capecitabine and 15.0 months for AI). For second-line treatment, the PFS was longer in the combination compared with capecitabine and Al groups (18 months vs. 5.0 months vs. 11.0 months, respectively). Median 2 year and 5 year survival did not show any significant differences among combination and monotherapy groups. The most common adverse events for the combination group were grade 1 and 2 hand-for syndrome (69%), grade 1 fatigue (64%) and grade 1 diarrhoea (29%). Three grade 3 hand-foot syndrome events were reported. Conclusions: Combination treatment with capecitabine and AI used as a first line or second line treatment was safe with much lowered toxicity. Prospective randomized clinical trials should evaluate the use of combination therapy in advanced breast cancer to confirm these findings.