Publications by authors named "Pooja Devi"

16 Publications

  • Page 1 of 1

Alleviation of heat stress by Chlorophytum borivilianum: impact on stress markers, antioxidant, and immune status in crossbred cows.

Trop Anim Health Prod 2021 Jun 8;53(3):351. Epub 2021 Jun 8.

Animal Physiology Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.

Eighteen crossbred Karan Fries (KF) cows in mid-lactation (av. 130 days) were selected from the livestock herd of the institute. The treatment for the experimental cows was as follows: no supplement (control), a low dose of Chlorophytum borivilianum (CB) at a dose rate of 40 mg/kg BW/day (T1, n = 6), and a high dose of CB at a dose rate of 80 mg/kg BW/day (T2, n = 6) for a period of 90 days in hot-humid season. Physiological responses like respiration rate (RR), pulse rate (PR), and rectal temperature (RT) were recorded in the morning (8.00 A.M.) and afternoon (2.30 P.M.) at weekly intervals. The expression of pro-inflammatory (IL-1β and TNF-α) and anti-inflammatory cytokine (IL-10) in PBMCs, the plasma level of antioxidants (SOD, catalase, TBARS, and TAC), hormones (cortisol, prolactin), and energy metabolites (glucose, NEFA, urea, and creatinine) were determined. Dry and wet bulb temperatures and minimum and maximum temperatures were recorded, and the THI was calculated. The values of PR and RT were decreased (p < 0.01) in the T2 group in comparison to T1. Plasma glucose level was lower, and NEFA, urea, and creatinine level were higher (p < 0.01) in the control group as compared to T2 and T1 groups, respectively. Plasma cortisol and prolactin levels were significantly higher (p < 0.01) in the control group and were lower in T1 and T2 groups. Feeding of CB in high dose decreased (p < 0.01) plasma SOD, catalase, TBARS, and improved TAC levels in T2 over the T1 group. The dietary supplementation of CB at a dose rate of 80 mg/kg BW/day was more effective in lowering the stress level and augments the immunity by downregulating pro-inflammatory and anti-inflammatory cytokine levels. Therefore, dietary CB supplementation could be used as an effective heat stress ameliorator in dairy cows.
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http://dx.doi.org/10.1007/s11250-021-02796-yDOI Listing
June 2021

Effect of Chlorophytum borivilianum supplementation on milk production, composition and fatty acid profile in crossbred cows during hot-humid season.

Trop Anim Health Prod 2021 Apr 30;53(2):300. Epub 2021 Apr 30.

Animal Physiology Division, ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.

The present investigation was carried out to test the efficacy of Chlorophytum borivilianum (CB) supplementation on milk production, composition, and fatty acid profile in crossbred (KF) cows. Eighteen crossbred cows were selected randomly from the institute herd and divided as control (n = 6), treatment 1 (T1, n = 6) and treatment 2 (T2, n = 6) based on body weight (av. 410.45, 424.47, 414.45 kg) and milk yield (av. 15.17, 15.80, 15.95 kg/d), respectively. The CB was supplemented at low dose at a dose rate of 40 mg/kg BW/day (T1) and high dose at a dose rate of 80 mg/kg BW/day (T2) during hot-humid (HH) season. The parameters like milk yield, dry matter intake (DMI), and body weight were recorded and milk composition viz., milk fat, solid not fat (SNF), protein, and fatty acid profile, somatic cell count (SCC), and plasminogen were estimated. Temperature humidity index (THI) was calculated to assess the level of heat stress on animals during hot-humid (HH) season. Body weight of crossbred cows did not vary between the groups during HH season. C. borivilianum supplementation in higher dose (80 mg/kg BW/day) increased DMI (per 100 kg BW) (p < 0.01) in T2 group KF cows in comparison to T1 and control group. The supplementation of CB in high dose increased milk yield, milk fat, protein, plasminogen and decreased SCC in comparison to low dose and control. Further, ratio of saturated to unsaturated fatty acids (SFAs:UFAs) was significantly reduced (p < 0.01) due to CB supplementation at higher dose in comparison to lower dose. It was concluded that supplementation of C. borivilianum at a dose rate of 80 mg/kg BW/day was found effective to augment milk production. The reduced saturated fatty acid, milk SCC, and the increase in unsaturated fatty acid content of milk, milk plasminogen suggest that its supplementation could be used in improving the mammary health and quality of milk production in dairy animals.
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http://dx.doi.org/10.1007/s11250-021-02747-7DOI Listing
April 2021

Nanostructures derived from expired drugs and their applications toward sensing, security ink, and bactericidal material.

Sci Total Environ 2021 Apr 24;764:144260. Epub 2020 Dec 24.

CSIR-Central Scientific Instruments Organisation, Chandigarh 160030, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.

In this research, a facile and economical route is introduced for the transformation of pharmaceutical waste (i.e., expired medicines) into value-added fluorescent carbon quantum dots (pharmaceutically derived CQDs abbreviated as 'P-CQDs'). The synthesized P-CQDs were identified to have surface functionalities of -OH, C=O, and C=C with an average size of ~2-3 nm and a high quantum yield of 35.3%. The photoluminescence of P-CQDs recorded a maximum optical emission intensity at 2.8 eV (425 nm). The binding of Cu (II) ions by -COOH functionalities on the surface of P-CQDs led to its fluorescence quenching (turn-off) over a wide Cu (II) concentration range of 0.25-50 ppm. The P-CQDs exhibited the detection limit of 0.66 ppm (well below the WHO permissible limit of 2 ppm). The fluorescence intensity of the P-CQDs-Cu (II) complex was recovered from NaHCOHence, their "off-on" behavior was also explored for security ink applications for information encryption and decryption. Moreover, the rich oxygenated groups on the surface of the P-CQDs were utilized for green synthesis of plasmonic [email protected] nanostructures, which were also demonstrated to have enhanced potential as bactericidal materials (e.g., against both E. coli and S. aureus). The overall results of this study are demonstrated to help create new and diverse routes for converting expired drugs into value-added nanostructures.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144260DOI Listing
April 2021

Chlorophyll()/Carbon Quantum Dot Bio-Nanocomposite Activated Nano-Structured Silicon as an Efficient Photocathode for Photoelectrochemical Water Splitting.

ACS Appl Mater Interfaces 2020 Aug 7;12(33):37218-37226. Epub 2020 Aug 7.

School of Materials Science, Indian Association for the Cultivation of Science, Kolkata 700032, India.

Solar-driven water splitting is considered as a futuristic sustainable way to generate hydrogen and chemical storage of solar energy. Further, considering the technological competence, silicon is one of the potential materials for developing large-scale and cost-effective photocathodes (PCs), but it lacks efficacy and stability. Here, we show that chlorophyll()/carbon quantum dots (Chl/CQDs) bio-nanocomposite (b-NC)-decorated Si-nanowires (SiNWs) as PC can surpass the reported efficiency for photoelectrochemical (PEC) hydrogen generation along with stability. The optimized heterojunction (Chl/CQDs_SiNW) significantly enhances broad-band solar absorption and protects Si surface from corrosion. Further, the appropriate band alignment enforces efficient photogenerated charge separation and possesses directional exciton transport property via the Förster resonance energy transfer (FRET) mechanism. This synergic effect demonstrates an ∼18 times increase in photocurrent density (26.36 mA/cm) compared to pristine SiNW PC at 1.07 V vs reversible hydrogen electrode (RHE). The efficiency reaches ∼7.86%, which is comparably the highest reported for hybrid Si-based photocathodes. Hydrogen evaluation rate was measured to be ∼113 μmol/h at 0.8 V vs RHE under 1 sun illumination. With Si-process line compatibility, this new finding opens a new direction toward the development of Si-based efficient and stable PCs at a large scale for commercial applications.
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http://dx.doi.org/10.1021/acsami.0c10279DOI Listing
August 2020

Surface Plasmon-Enhanced Carbon Dot-Embellished Multifaceted Si(111) Nanoheterostructure for Photoelectrochemical Water Splitting.

ACS Appl Mater Interfaces 2020 Jun 12;12(25):28792-28800. Epub 2020 Jun 12.

School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.

Because of the excellent electronic properties, Si is a well-established semiconducting material for PV technology. However, slow kinetics and a fast corroding nature make Si inefficient for the hydrogen evolution reaction (HER) in photoelectrochemical (PEC) applications. Herein, we demonstrate a multifacet Si nanowire (SiNW) decorated with surface plasmon-enhanced carbon quantum dots (AuCQDs) as efficient, stable, economical, and scalable photocathodes (PCs) for HER. The PEC performance of SiNW_AuCQDs has more than a fourfold efficiency enhancement than the pristine SiNW, which we have attributed to the combined effect of enhanced solar absorption and efficient carrier transport. The optimized PC SiNW_AuCQDs results in the highest photocurrent ∼1.7 mA/cm, an applied bias photon-to-current conversion efficiency of ∼0.8%, and H gas evolution rate of ∼182.93 μmol·h. Furthermore, these SiNW_AuCQDs PCs provide extraordinary stability under continuous operating conditions with 1 sun illumination (100 mW/cm). The process-line compatible fabrication process of these PCs will open a new direction at the wafer-level designing of a heterostructure for large-scale solar-fuel conversion.
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http://dx.doi.org/10.1021/acsami.0c05591DOI Listing
June 2020

Papillary Thyroid Carcinoma in Struma Ovarii.

Cureus 2020 Apr 7;12(4):e7582. Epub 2020 Apr 7.

Pathology, Rutgers Robert Wood Johnson Medical School, New Brunswick, USA.

Struma ovarii is a variant of a germ cell tumor composed predominantly of thyroid tissue. It is most often unilateral. The incidence of malignancy arising in patients with struma ovarii is rare. Here, we present a case of struma ovarii in a female presented with abdominal distension. The patient was treated with a total hysterectomy and bilateral salpingo-oophorectomy, which revealed an enlarged cystically dilated ovary. Histopathologic examination showed mature thyroid follicles with abundant colloid consistent with struma ovarii and focal area with nuclear features of papillary thyroid carcinoma. No other teratomatous elements were identified. Thyroid hormone levels were within their respective reference ranges. A diagnosis of struma ovarii should be considered in the differential diagnosis of pelvic masses in peri- and postmenopausal patients.
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http://dx.doi.org/10.7759/cureus.7582DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7205381PMC
April 2020

Modified p-GaN Microwells with Vertically Aligned 2D-MoS for Enhanced Photoelectrochemical Water Splitting.

ACS Appl Mater Interfaces 2020 Mar 13;12(12):13797-13804. Epub 2020 Mar 13.

School of Materials Sciences, Indian Association for the Cultivation of Science, Kolkata 700030, India.

Photoelectrochemical (PEC) water splitting has been considered as the future technology for storing solar energy in the chemical bonds. However, due to the search of ideal heterostructured materials for photoanode/cathode, the full potential of this technology has not been realized yet. Herein we present, the nanotextured hexagonal microwell of p-GaN [p-GaN(Et)] synthesized via wet chemical etching route as a photocathode (PC) for PEC water splitting. The p-GaN(Et) was further modified by interconnected nanowall network of two-dimensional (2D) transition metal dichalcogenide (MoS) [2D-MoS/p-GaN(Et)]. Both PCs were characterized for their morphology, structures, and optical and electronic properties. The overall PEC performance was validated through photocurrent values followed by the amount of hydrogen and oxygen evolution. This combination of 2D-MoS/p-GaN(Et) outplayed pristine p-GaN(Et) by several orders of magnitude in overall PEC performance. The extraordinary stability under a continuous operating condition with 1 sun illumination (100 mW/cm) provides the much-needed flavor of an efficient photocathode. The optimized photocathode [2D-MoS/p-GaN(Et)] shows the highest applied bias photon-to-current conversion efficiency of ∼3.18% with hydrogen evolution rate of 89.56 μmol/h at -0.3 V vs RHE. This wafer-level cost-effective synthesis of 2D-MoS/GaN heterostructure based PCs opens a new way for large-scale solar-fuel conversion.
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http://dx.doi.org/10.1021/acsami.9b20969DOI Listing
March 2020

Pulmonary Carcinosarcoma: A Case Report of Biphasic Lung Tumor.

Cureus 2019 Sep 13;11(9):e5643. Epub 2019 Sep 13.

Pathology, Saint Barnabas Medical Center, Robert Wood Johnson Barnabas Health, Livingston, USA.

Pulmonary carcinosarcoma is an unusual biphasic tumor of the lung with carcinomatous and sarcomatous components. We report a case in a 71-year-old female who presented with a 13-cm lung mass. Microscopic examination revealed squamous cell carcinoma and chondrosarcoma with focal spindle cell atypia. In the most recent version of the World Health Organization (WHO) classification, carcinosarcoma is included in the category of sarcomatous neoplasms with a poorer prognosis than non-small cell lung carcinoma.
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http://dx.doi.org/10.7759/cureus.5643DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6822921PMC
September 2019

Invasive versus Non-invasive Positive Pressure Ventilation In Chronic Obstructive Pulmonary Disease Complicated By Acute Respiratory Failure.

Cureus 2019 Aug 18;11(8):e5418. Epub 2019 Aug 18.

Internal Medicine, Jinnah Postgraduate Medical Center, Karachi, PAK.

Introduction Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is frequently encountered as a medical emergency. AECOPD is the third leading medical cause of hospitalization due to acute respiratory failure (ARF). The utilization of ventilators for patients with ARF secondary to AECOPD has increased. There has been a major inclination towards utilization of non-invasive positive pressure ventilation (NIPPV) and sparing invasive positive pressure ventilation (IPPV) for life-threatening respiratory distress and/or in patients where NIPPV failure is observed. The aim of this observational study was to compare the clinical and laboratory parameters patients with chronic obstructive pulmonary disease (COPD) complicated by ARF admitted in the intensive care unit (ICU). Methods In the prospective observational study with known cases of COPD complicated by ARF, patients were grouped into NIPPV and IPPV groups based on their clinical and laboratory parameters. Thirty patients were included in each group. Demographic data was collected. Clinical and laboratory parameters were evaluated at baseline and at 24 hours of ventilation. The outcome was assessed in terms of duration of ventilation, hospital and ICU stay and overall mortality. Data was entered and analyzed using SPSS version 22.0 (IBM Corp., Armonk, NY). Results Both IPPV and NIPPV groups demonstrated marked reduction in partial pressure of carbon dioxide (PaCO) with 24 hours of ventilation (for IPPV: 78.1 ± 20.2 vs. 69.1 ± 20.2; p=0.08) (for NIPPV: 68.1 ± 17.8 vs. 57.2 ± 21.5; p=0.03). In NIPPV group, there was significant improvement in partial pressure of oxygen (PaO) (p=0.009), respiratory rate (p=0.008), heart rate (p<0.0001), systolic blood pressure (p=0.03), and diastolic blood pressure (p<0.0001). These parameters did not improve significantly in the IPPV group except for systolic blood pressure (p=0.008). The NIPPV failure rate was 20%. NIPPV patients had a significantly shorter duration of ventilation, ICU stay, and hospital stay. In-ICU mortality was significantly lower in the NIPPV group as compared to IPPV (13% vs. 40%; p=0.01). There was no difference in post-ICU in-hospital mortality between the two groups (6.7% vs. 16.7%; p=0.13). Conclusion Both NIPPV and IPPV are effective in normalizing acidosis and hypercapnia in patients with COPD complicated by ARF. Patients managed with non-invasive mode of ventilation have a shorter duration of ICU as well as hospital stay. Survival rates are also better as compared to patients managed with invasive ventilation.
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http://dx.doi.org/10.7759/cureus.5418DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6795366PMC
August 2019

The advanced role of carbon quantum dots in nanomedical applications.

Biosens Bioelectron 2019 Sep 7;141:111158. Epub 2019 Mar 7.

Department of Civil & Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul 04763, Republic of Korea. Electronic address:

Carbon quantum dots (CQDs) have emerged as a potential material in the diverse fields of biomedical applications due to their numerous advantageous properties including fluorescence, water solubility, biocompatibility, low toxicity, small size and ease of modification, inexpensive scale-up production, and versatile conjugation with other nanoparticles. Thus, CQDs became a preferable choice in various biomedical applications such as nanocarriers for drugs, therapeutic genes, photosensitizers, and antibacterial molecules. Further, their potentials have also been verified in multifunctional diagnostic platforms, cellular and bacterial bio-imaging, development of theranostics nanomedicine, etc. This review provides a concise insight into the progress and evolution in the field of CQD research with respect to methods/materials available in bio-imaging, theranostics, cancer/gene therapy, diagnostics, etc. Further, our discussion is extended to explore the role of CQDs in nanomedicine which is considered to be the future of biomedicine. This study will thus help biomedical researchers in tapping the potential of CQDs to overcome various existing technological challenges.
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http://dx.doi.org/10.1016/j.bios.2019.02.059DOI Listing
September 2019

Development of novel gastroretentive salbutamol sulfate-loaded sodium alginate-pectin bubble beads prepared by co-axial needle air-injection method and in vivo clinical evaluation by ultrasound studies.

Eur J Pharm Sci 2018 Sep 12;122:359-373. Epub 2018 Jul 12.

College of Pharmacy, PGIMS, University of Health Sciences, Rohtak 124001, Haryana, India. Electronic address:

In the present study, the salbutamol sulfate-loaded sodium alginate-pectin (SS-loaded SA-PEC) bubble beads have been optimized and evaluated for drug loading, in vitro drug release, in vivo floating behavior in the stomach, etc. Nine batches (F1-F9) of bubble beads with different SA and PEC contents were prepared by novel co-axial needle air-injection method and related to their percent drug loading efficiency (%DLE) and percent drug release at 4 h (%R) as response factors. The multivariate analysis has shown the effect of SA/PEC ratio, total polymer content, as well as their interaction on %DLE and %R. In the quantitative modeling, the satisfactory adjustment of the linear models (along with interaction terms) with the experimental data for both %DLE and %R has confirmed the findings of the multivariate analysis. The optimized SS-loaded SA-PEC bubble beads based on 2D (contours), 3D, desirability, and overlay plots has exhibited %DLE of 87.35 ± 2.48% (n = 3 and error = 2.94%) and %R of 85.79 ± 2.98% (n = 3 and error = 0.25%). The in vitro drug release studies have shown almost complete (≥85%) SS release from all the batches within 4-6 h in simulated gastric fluid (SGF) pH 1.2. The in vivo clinical findings by ultrasound studies have shown excellent floatation (>6 h) behavior of bubble beads in the upper gastrointestinal tract (GIT) and efficient stomach-specific gastroretention.
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http://dx.doi.org/10.1016/j.ejps.2018.07.019DOI Listing
September 2018

Waste derivitized blue luminescent carbon quantum dots for selenite sensing in water.

Talanta 2017 Aug 23;170:49-55. Epub 2017 Mar 23.

Central Scientific Instruments Organisation, Chandigarh 160030, India.

Herein, we report an environmental friendly, facile, and completely green synthetic method for producing carbon quantum dots (CQDs) from whey, a major dairy waste. The as-prepared monodispersed diameter CQDs exhibit blue luminescence with noteworthy quantum yield (~11.4%) and excitation dependent emission behaviour. Nuclear magnetic resonance (NMR) analysis reveals the presence of aromatized carbon peaks, leading to polymerized CQDs diameter architecture during whey pyrolysis. The X-ray and selected area electron diffraction patterns confirm their amorphous nature. Further, we demonstrate, these CQDs as an effective sensor probe for selective selenite monitoring in water upon functionalization with appropriate ligand. The functionalized GCQDs probe is shown to detect selenite with high sensitivity in 10-1000ppb detection range. Further it is selective for selenite over other relevant ions (such as Cu, As, As, Pb, Ni, Se, Cl, Br, NO, NO and F) and displays a sub-ppb detection limit at 1.1% relative standard deviation.
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http://dx.doi.org/10.1016/j.talanta.2017.03.069DOI Listing
August 2017

Ultrasensitive and Selective Sensing of Selenium Using Nitrogen-Rich Ligand Interfaced Carbon Quantum Dots.

ACS Appl Mater Interfaces 2017 Apr 6;9(15):13448-13456. Epub 2017 Apr 6.

Academy of Scientific and Innovative Research (AcSIR), Council of Scientific and Industrial Research , New Delhi 110001, India.

This work reports a label-free, ultrasensitive, and selective optical chemosensory system for trace level detection of selenite (SeO), the most toxic form of selenium, in water. The probe, i.e., carbon quantum dots (CQDs), is designed from citric acid by means of pyrolysis and is interfaced with a newly synthesized nitrogen-rich ligand to create a selective sensor platform (functionalized CQDs, fCQDs) for selenite in a water matrix. Spectral (NMR, UV-vis, photoluminescence, Raman, and Fourier transform infrared analyses) and structural (high-resolution transmission electron microscopy) characteristics of the designed new probe were investigated. The developed sensor exhibits high sensitivity (limit of detection = 0.1 ppb), a wide detection range (0.1-1000 ppb range, relative standard deviation: 3.2%), and high selectivity even in the presence of commonly interfering ions reported to date, including Cl, NO, NO, Br, F, As(V), As(III), Cu, Pb, Cd, Zn, Sr, Rb, Na, Ca, Cs, K, Mg, Li, NH, Co, etc. The observed selectivity is due to designed ligand characteristics in terms of strong Se-N chemistry. Ultrafast spectroscopic analysis of the fCQDs in the absence and presence of selenite was studied to understand the sensing mechanism. The sensor was successfully exemplified for real water samples and exhibits comparative performance to conventional ion channel chromatography as well as flame atomic absorption spectroscopy for selenite analysis. The promising results pave ways for realization of a field deployable device based upon a developed probe for selenite quantification in water.
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http://dx.doi.org/10.1021/acsami.7b00991DOI Listing
April 2017

Selective electrochemical sensing for arsenite using rGO/FeO nanocomposites.

J Hazard Mater 2017 Jan 2;322(Pt A):85-94. Epub 2016 Mar 2.

Central Scientific Instruments Organisation, Sector-30 C, Chandigarh 160030, India.

Herein, we report rGO/FeO nanocomposites (NCs) free from noble metals, synthesized by facile one step chemical reduction method, for electrochemical detection of arsenite in water by square wave anodic stripping Voltammetry (SWASV). The synthesized NCs were characterized for its optical, morphological and structural properties. The NCs modified glassy carbon (GCE), NCs/GCE, electrodes showed a higher sensitivity (0.281μA/ppb) and lower LOD (0.12ppb) under optimized experimental conditions. The proposed NCs/GCE electrodes show no interference towards arsenite species in the presence of common cationic interferants, namely, Cu(II), Pb(II), Ni(II), Co(II), Cd(II), Cr(II), Zn(II), etc. In addition, the proposed electrode demonstrates a good stability, reproducibility and potential practical application in electrochemical detection of arsenite.
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http://dx.doi.org/10.1016/j.jhazmat.2016.02.066DOI Listing
January 2017

Isotopic composition of atmospheric moisture from pan water evaporation measurements.

Isotopes Environ Health Stud 2015 ;51(3):426-38

a Department of Physics , Indian Institute of Technology Roorkee , Roorkee , India.

A continuous and reliable time series data of the stable isotopic composition of atmospheric moisture is an important requirement for the wider applicability of isotope mass balance methods in atmospheric and water balance studies. This requires routine sampling of atmospheric moisture by an appropriate technique and analysis of moisture for its isotopic composition. We have, therefore, used a much simpler method based on an isotope mass balance approach to derive the isotopic composition of atmospheric moisture using a class-A drying evaporation pan. We have carried out the study by collecting water samples from a class-A drying evaporation pan and also by collecting atmospheric moisture using the cryogenic trap method at the National Institute of Hydrology, Roorkee, India, during a pre-monsoon period. We compared the isotopic composition of atmospheric moisture obtained by using the class-A drying evaporation pan method with the cryogenic trap method. The results obtained from the evaporation pan water compare well with the cryogenic based method. Thus, the study establishes a cost-effective means of maintaining time series data of the isotopic composition of atmospheric moisture at meteorological observatories. The conclusions drawn in the present study are based on experiments conducted at Roorkee, India, and may be examined at other regions for its general applicability.
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http://dx.doi.org/10.1080/10256016.2015.1037301DOI Listing
June 2016

Synthesis, characterization and bactericidal activity of silica/silver core-shell nanoparticles.

J Mater Sci Mater Med 2014 May 11;25(5):1267-73. Epub 2014 Feb 11.

Academy of Scientific and Innovative Research, Central Scientific Instruments Organisation, Sector 30 C, Chandigarh, 160030, India.

Silica/silver core-shell nanoparticles (NPs) were synthesized by coating silver NPs on silica core particles (size ~300 ± 10 nm) via electro less reduction method. The core-shell NPs were characterized for their structural, morphological, compositional and optical behavior using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and UV-Visible spectroscopy, respectively. The size (16-35 nm) and loaded amount of silver NPs on the silica core were found to be dependent upon reaction time and activation method of silica. The bactericidal activity of the NPs was tested by broth micro dilution method against both Bacillus subtilis (gram positive) and Escherichia coli ATCC25922 (gram negative) bacterium. The bactericidal activity of silica/silver core-shell NPS is more against E. coli ATCC25922, when compared to B. subtilis. The minimal inhibitory concentration of the core-shell NPs ranged from 7.8 to 250 μg/mL and is found to be dependent upon the amount of silver on silica, the core. These results suggest that silica/silver core-shell NPs can be utilized as a strong substitutional candidate to control pathogenic bacterium, which are otherwise resistant to antibiotics, making them applicable in diverse medical devices.
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http://dx.doi.org/10.1007/s10856-014-5165-9DOI Listing
May 2014