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Gupta M, Bansal A, Chakrapani V, Jaiswal N, Kiran T. The effectiveness of prenatal and postnatal home visits by paramedical professionals and women's group meetings in improving maternal and child health outcomes in low and middle-income countries: a systematic review and meta-analysis. Public Health 2023; 215:106-117. [PMID: 36682079 DOI: 10.1016/j.puhe.2022.11.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 01/21/2023]
Abstract
OBJECTIVE To assess the effectiveness of prenatal and postnatal home visits (HVs) and women group meetings (WGMs) by paramedical professionals to improve maternal and child health outcomes in low- and middle-income countries (LMICs). STUDY DESIGN Systematic review and meta-analysis. METHODS We conducted a systematic review of trials published till December 2020, as per registered protocol in The International Prospective Register of Systematic Reviews (PROSPERO) (CRD42018091968). Outcomes were neonatal mortality rate (NMR), maternal mortality ratio (MMR), the incidence of low birth weight, and still birth rate (SBR). The Cochrane Pregnancy and Childbirth Group's Trials Register, Cochrane Central Register of Controlled Trials, PubMed, and Excerpta Medica Database (EMBASE) were searched. Pooled results were estimated using random-effects meta-analysis in RevMan version 5.2. RESULTS Twenty-five trials met the inclusion criteria. HVs were the key intervention in 12, WGMs in 11, and both interventions in 2 trials. The pooled estimates have shown that NMR was significantly reduced by HVs (OR 0.77, confidence interval [CI]: 0.67-0.90, P = 0.0007, I2 = 77%) and WGMs (OR 0.76, CI: 0.65-0.90, P = 0.001, I2 = 71%). SBR was significantly reduced by HVs (OR 0.77, CI: 0.70-0.85; P < 0.001, I2 = 0%). Subgroup analysis of studies in which more than 10% of pregnant women participated in the WGMs showed significant reduction in NMR (OR 0.67, CI 0.58-0.77, P = 0.00001, I2 = 31%) and MMR (OR 0.55, CI 0.36-0.84, P = 0.005, I2 = 27%). Two studies reported improvement in birth weight by HVs. CONCLUSIONS HVs and WGMs (with >10% pregnant women) by paramedical professionals are effective strategies in reducing the NMR and MMR in LMICs. HVs were also effective in reducing SBR.
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Affiliation(s)
- M Gupta
- Postgraduate Institute of Medical Education and Research, Chandigarh, India.
| | - A Bansal
- Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - V Chakrapani
- Centre for Sexuality and Health Research and Policy (C-SHaRP), Chennai, India
| | - N Jaiswal
- Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - T Kiran
- Postgraduate Institute of Medical Education and Research, Chandigarh, India
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Chakrapani V, Wang C, Wang Q, Smieszek N. Direct Determination of Mn Valence States in Mixed‐valent Manganates by Photoluminescence Spectroscopy. SURF INTERFACE ANAL 2022. [DOI: 10.1002/sia.7144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering Rensselaer Polytechnic Institute Troy New York United States
| | - Chenying Wang
- Howard P. Isermann Department of Chemical and Biological Engineering Rensselaer Polytechnic Institute Troy New York United States
| | - Qi Wang
- Howard P. Isermann Department of Chemical and Biological Engineering Rensselaer Polytechnic Institute Troy New York United States
| | - Nicholas Smieszek
- Howard P. Isermann Department of Chemical and Biological Engineering Rensselaer Polytechnic Institute Troy New York United States
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Roy I, Wang C, Smieszek N, Li X, Tsapatsaris L, Chakrapani V. Formation of the Metastable Mn III Water Oxidation Intermediate in Birnessite is Controlled by a Dissolution-Deposition Process Involving Labile Mn II. ChemSusChem 2022; 15:e202200062. [PMID: 35253389 DOI: 10.1002/cssc.202200062] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/25/2022] [Indexed: 06/14/2023]
Abstract
Birnessite, the closest naturally occurring analog of the Mn4 CaO5 cluster of photosystem II, is an important model compound in the development of bio-inspired electrocatalysts for the water oxidation reaction. The present work reports the formation mechanism of the key MnIII intermediate realized through the study of the effects of several electrolyte anions and cations on the catalytic efficiency of birnessite. In situ spectroelectrochemical measurements show that the activity is controlled by a dynamic dissolution-oxidation process, wherein MnIII is formed through the oxidation of labile uncomplexed MnII that reversibly shuttles between the birnessite and the electrolyte in a manner similar to the photoactivation in photosystem II. The role of electrolyte cations of different ionic radii and hydration strengths is to control the interlayer spacing, whereas electrolyte anions control the extent of deprotonation of complexed MnII in the lattice. Both in turn govern the shuttling efficiency of uncomplexed MnII and its subsequent electro-oxidation to MnIII .
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Affiliation(s)
- Indroneil Roy
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
| | - Chenying Wang
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
| | - Nicholas Smieszek
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
| | - Xinran Li
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
| | - Leonidas Tsapatsaris
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA
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Joshi S, Smieszek N, Chakrapani V. Effects of charge fluctuation and charge regulation on the phase transitions in stoichiometric VO 2. Sci Rep 2020; 10:17121. [PMID: 33051507 PMCID: PMC7553960 DOI: 10.1038/s41598-020-73447-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 09/17/2020] [Indexed: 11/09/2022] Open
Abstract
Detailed electrical and photoemission studies were carried out to probe the chemical nature of the insulating ground state of VO2, whose properties have been an issue for accurate prediction by common theoretical probes. The effects of a systematic modulation of oxygen over-stoichiometry of VO2 from 1.86 to 2.44 on the band structure and insulator-metal transitions are presented for the first time. Results offer a different perspective on the temperature- and doping-induced IMT process. They suggest that charge fluctuation in the metallic phase of intrinsic VO2 results in the formation of e- and h+ pairs that lead to delocalized polaronic V3+ and V5+ cation states. The metal-to-insulator transition is linked to the cooperative effects of changes in the V-O bond length, localization of V3+ electrons at V5+ sites, which results in the formation of V4+-V4+ dimers, and removal of [Formula: see text] screening electrons. It is shown that the nature of phase transitions is linked to the lattice V3+/V5+ concentrations of stoichiometric VO2 and that electronic transitions are regulated by the interplay between charge fluctuation, charge redistribution, and structural transition.
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Affiliation(s)
- Siddharth Joshi
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Nicholas Smieszek
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA. .,Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
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Chakrapani V. Probing Active Sites and Reaction Intermediates of Electrocatalysis Through Confocal Near-Infrared Photoluminescence Spectroscopy: A Perspective. Front Chem 2020; 8:327. [PMID: 32411668 PMCID: PMC7199742 DOI: 10.3389/fchem.2020.00327] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022] Open
Abstract
Electrocatalytic reactions such as oxygen evolution (OER) and oxygen reduction reactions (ORR) are one of the most complex heterogeneous charge transfer processes because of the involvement of multiple proton-coupled-electron transfer steps over a narrow potential range and the formation/breaking of oxygen-oxygen bonds. Obtaining a clear mechanistic picture of these reactions on some highly active strongly-correlated oxides such as MnOx, NiOx, and IrOx has been challenging due to the inherent limitations of the common spectroscopic tools used for probing the reactive intermediates and active sites. This perspective article briefly summarizes some of the key challenges encountered in such probes and describes some of unique advantages of confocal near-infrared photoluminescence (NIR-PL) technique for probing surface and bulk metal cation states under in-situ and ex-situ electrochemical polarization studies. Use of this technique opens up a new avenue for studying changes in the electronic structure of metal oxides occurring as a result of perturbation of defect equilibria, which is crucial in a broad range of heterogeneous systems such as catalysis, photocatalysis, mineral redox chemistry, and batteries.
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Affiliation(s)
- Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States.,Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY, United States
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Bhattacharya S, Roy I, Tice A, Chapman C, Udangawa R, Chakrapani V, Plawsky JL, Linhardt RJ. High-Conductivity and High-Capacitance Electrospun Fibers for Supercapacitor Applications. ACS Appl Mater Interfaces 2020; 12:19369-19376. [PMID: 32275134 DOI: 10.1021/acsami.9b21696] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Electrospinning is a simple method for producing nanoscale or microscale fibers from a wide variety of materials. Intrinsically conductive polymers (ICPs), such as polyaniline (PANI), show higher conductivities with the use of secondary dopants like m-cresol. However, due to the low volatility of most secondary dopants, it has not been possible to electrospin secondary doped ICP fibers. In this work, the concept of secondary doping has been applied for the first time to electrospun fibers. Using a novel design for rotating drum electrospinning, fibers were efficiently and reliably produced from a mixture of low- and high-volatility solvents. The conductivity of electrospun PANI-poly(ethylene oxide) (PEO) fibers prepared was 1.73 S/cm, two orders of magnitude higher than the average value reported in the literature. These conductive fibers were tested as electrodes for supercapacitors and were shown to have a specific capacitance as high as 3121 F/g at 0.1 A/g, the highest value reported, thus far, for PANI-PEO electrospun fibers.
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Affiliation(s)
- Somdatta Bhattacharya
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Indroneil Roy
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Aaron Tice
- Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, United States
| | - Caitlyn Chapman
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, United States
| | - Ranodhi Udangawa
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, United States
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Joel L Plawsky
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Robert J Linhardt
- Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, United States
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Adarsh KS, Chandrasekaran N, Chakrapani V. In-situ Spectroscopic Techniques as Critical Evaluation Tools for Electrochemical Carbon dioxide Reduction: A Mini Review. Front Chem 2020; 8:137. [PMID: 32266204 PMCID: PMC7099648 DOI: 10.3389/fchem.2020.00137] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 02/14/2020] [Indexed: 11/13/2022] Open
Abstract
Electrocatalysis plays a crucial role in modern electrochemical energy conversion technologies as a greener replacement for conventional fossil fuel-based systems. Catalysts employed for electrochemical conversion reactions are expected to be cheaper, durable, and have a balance of active centers (for absorption of the reactants, intermediates formed during the reactions), porous, and electrically conducting material to facilitate the flow of electrons for real-time applications. Spectroscopic and microscopic studies on the electrode-electrolyte interface may lead to better understanding of the structural and compositional deviations occurring during the course of electrochemical reaction. Researchers have put significant efforts in the past decade toward understanding the mechanistic details of electrochemical reactions which resulted in hyphenation of electrochemical-spectroscopic/microscopic techniques. The hyphenation of diverse electrochemical and conventional microscopic, spectroscopic, and chromatographic techniques, in addition to the elementary pre-screening of electrocatalysts using computational methods, have gained deeper understanding of the electrode-electrolyte interface in terms of activity, selectivity, and durability throughout the reaction process. The focus of this mini review is to summarize the hyphenated electrochemical and non-electrochemical techniques as critical evaluation tools for electrocatalysts in the CO2 reduction reaction.
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Affiliation(s)
- K. S. Adarsh
- CSIR-Central Electrochemical Research Institute, Karaikudi, India
| | | | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States
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Wang Q, Puntambekar A, Chakrapani V. Co-adsorption of water and oxygen on GaN: Effects of charge transfer and formation of electron depletion layer. J Chem Phys 2017; 147:104703. [PMID: 28915758 DOI: 10.1063/1.4991322] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Species from ambient atmosphere such as water and oxygen are known to affect electronic and optical properties of GaN, but the underlying mechanism is not clearly known. In this work, we show through careful measurement of electrical resistivity and photoluminescence intensity under various adsorbates that the presence of oxygen or water vapor alone is not sufficient to induce electron transfer to these species. Rather, the presence of both water and oxygen is necessary to induce electron transfer from GaN that leads to the formation of an electron depletion region on the surface. Exposure to acidic gases decreases n-type conductivity due to increased electron transfer from GaN, while basic gases increase n-type conductivity and PL intensity due to reduced charge transfer from GaN. These changes in the electrical and optical properties, as explained using a new electrochemical framework based on the phenomenon of surface transfer doping, suggest that gases interact with the semiconductor surface through electrochemical reactions occurring in an adsorbed water layer present on the surface.
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Affiliation(s)
- Qi Wang
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Ajinkya Puntambekar
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
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Puntambekar A, Wang Q, Miller L, Smieszek N, Chakrapani V. Electrochemical Charging of CdSe Quantum Dots: Effects of Adsorption versus Intercalation. ACS Nano 2016; 10:10988-10999. [PMID: 27943668 DOI: 10.1021/acsnano.6b05779] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Effects of electrochemical charging of quantum dots (QDs) have been reported previously, wherein optical and electrical properties could be modulated through cation adsorption and electron injection into the quantum-confined 1Se states. In this work, we report two different modes of electrochemical double-layer charging in CdSe QDs and their effects on the electronic and optical properties. We show that the charging mechanism at the interface involves cation intercalation for smaller ions, such as Li+, Na+, or K+, and cation adsorption for larger bulky ions, such as tetrabutylammonium ions, where steric hindrance precludes intercalation. As a result, while cation adsorption leads to an increase in the absorbance in the mid-infrared spectral range, cation intercalation into the CdSe core results in an absorbance increase from the visible to infrared spectral range, an enhancement in radiative lifetime of e-, an increase of 158% in the intensity of band-edge photoluminescence, and strong emission in the near-infrared spectral range as a result of the formation of Se vacancies. The nature of charging mechanisms is discussed using the results of combined photoluminescence, radiative lifetime, and X-ray photoemission studies. The cation-coupled electronic and optical modulation reported here in CdSe QDs have important implications for electrochromic smart windows, photovoltaics, and other devices.
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Affiliation(s)
- Ajinkya Puntambekar
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics & Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Qi Wang
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics & Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Lauren Miller
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics & Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Nicholas Smieszek
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics & Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics & Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
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Wang Q, Puntambekar A, Chakrapani V. Vacancy-Induced Semiconductor-Insulator-Metal Transitions in Nonstoichiometric Nickel and Tungsten Oxides. Nano Lett 2016; 16:7067-7077. [PMID: 27696859 DOI: 10.1021/acs.nanolett.6b03311] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Metal-insulator transitions in strongly correlated oxides induced by electrochemical charging have been attributed to formation of vacancy defects. However, the role of native defects in affecting these transitions is not clear. Here, we report a new type of phase transition in p-type, nonstoichiometric nickel oxide involving a semiconductor-to-insulator-to-metal transition along with the complete reversal of conductivity from p- to n-type at room temperature induced by electrochemical charging in a Li+-containing electrolyte. Direct observation of vacancy-ion interactions using in situ near-infrared photoluminescence spectroscopy show that the transition is a result of passivation of native nickel (cationic) vacancy defects and subsequent formation of oxygen (anionic) vacancy defects driven by Li+ insertion into the lattice. Changes in the oxidation states of nickel due to defect interactions probed by X-ray photoemission spectroscopy support the above conclusions. In contrast, n-type, nonstoichiometric tungsten oxide shows only insulator-to-metal transition, which is a result of oxygen vacancy formation. The defect-property correlations shown here in these model systems can be extended to other oxides.
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Affiliation(s)
- Qi Wang
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Ajinkya Puntambekar
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Vidhya Chakrapani
- Howard P. Isermann Department of Chemical and Biological Engineering and ‡Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
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Panda RP, Chakrapani V, Patra SK, Saha JN, Jayasankar P, Kar B, Sahoo PK, Barman HK. First evidence of comparative responses of Toll-like receptor 22 (TLR22) to relatively resistant and susceptible Indian farmed carps to Argulus siamensis infection. Dev Comp Immunol 2014; 47:25-35. [PMID: 24998226 DOI: 10.1016/j.dci.2014.06.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/24/2014] [Accepted: 06/26/2014] [Indexed: 06/03/2023]
Abstract
Toll-like receptor 22 (TLR22) is present in teleost but not in mammals. Among Indian farmed carps, Catla catla is relatively more resistant than Labeo rohita to Argulus siamensis lice infection. TLR22 is believed to be associated with innate immunity against ectoparasite infection. To investigate the TLR22 mediated immunity against argulosis, we have cloned and characterized TLR22 genes of L. rohita (rTLR22) and C. catla (cTLR22). The full-length cDNAs of rTLR22 and cTLR22 contained an open reading frame of 2838 and 2841 nucleotides, respectively; bearing the typical structural features. Phylogenetically rTLR22/cTLR22 was most closely related to Cyprinus carpio (common carp) counterpart, having highest sequence identity of 86.0%. The TIR domain remained highly conserved with 90% identity within freshwater fishes. The sequence information of cDNA and genomic DNA together revealed that the rTLR22/cTLR22 genes are encoded by uninterrupted exons. The co-habitation challenge study with A. siamensis infection confirmed that C. catla is comparatively more resistant than L. rohita. Further, comparative mRNA expression profile in immune relevant tissues also suggested about the participatory role of TLR22 during lice infection. However, TLR22 might not solely be involved in conferring relative resistance among carp species against argulosis.
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Affiliation(s)
- Rudra Prasanna Panda
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - V Chakrapani
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Swagat Kumar Patra
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Jatindra Nath Saha
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Pallipuram Jayasankar
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Banya Kar
- Fish Health Management Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Pramoda Kumar Sahoo
- Fish Health Management Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India
| | - Hirak Kumar Barman
- Fish Genetics and Biotechnology Division, Central Institute of Freshwater Aquaculture (Indian Council of Agricultural Research), Kausalyaganga, Bhubaneswar 751002, Odisha, India.
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Yadav D, Chakrapani V, Goswami P, Ramanathan S, Ramakrishnan L, George B, Sen S, Paranjape R. P4.041 Factors Associated with Frequent Alcohol Drinking Among Men Who Have Sex with Men: Findings from a Multi-Site Bio-Behavioural Survey in India. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ramanathan S, Ramakrishnan L, Goswami P, Yadav D, George B, Sen S, Chakrapani V, Paranjape R, Subramanian T, Rachakulla H. O23.2 Correlates of Inconsistent Condom Use During Anal Sex with Female Sex Workers (FSWs) Among Male Clients: Survey Findings from Three High Prevalence States of India. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Ramanathan S, Chakrapani V, Ramakrishnan L, Goswami P, Yadav D, George B, Sen S, Paranjape R, Subramanian T, Rachakulla H. P6.027 Factors Associated with Use of Water-Based Lubricants by Men Who Have Sex with Men: Findings from a Bio-Behavioural Study in Three Indian States. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.1181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Chakrapani V, Newman PA, Jerajani J, Shanmugam M, Singhal N. A social ecological model of willingness to participate in HIV vaccine trials among men who have sex with men in Chennai and Mumbai, India. Retrovirology 2012. [PMCID: PMC3441898 DOI: 10.1186/1742-4690-9-s2-p111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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Chakrapani V, Baker D, Kamat PV. Understanding the role of the sulfide redox couple (S2-/S(n)2-) in quantum dot-sensitized solar cells. J Am Chem Soc 2011; 133:9607-15. [PMID: 21568293 DOI: 10.1021/ja203131b] [Citation(s) in RCA: 267] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The presence of sulfide/polysulfide redox couple is crucial in achieving stability of metal chalcogenide (e.g., CdS and CdSe)-based quantum dot-sensitized solar cells (QDSC). However, the interfacial charge transfer processes play a pivotal role in dictating the net photoconversion efficiency. We present here kinetics of hole transfer, characterization of the intermediates involved in the hole oxidation of sulfide ion, and the back electron transfer between sulfide radical and electrons injected into TiO(2) nanoparticles. The kinetic rate constant (10(7)-10(9) s(-1)) for the hole transfer obtained from the emission lifetime measurements suggests slow hole scavenging from CdSe by S(2-) is one of the limiting factors in attaining high overall efficiency. The presence of the oxidized couple, by addition of S or Se to the electrolyte, increases the photocurrent, but it also enhances the rate of back electron transfer.
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Affiliation(s)
- Vidhya Chakrapani
- Notre Dame Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Newman PA, Chakrapani V, Cook C, Shunmugam M, Kakinami L. Determinants of Sexual Risk Behavior Among Men Who Have Sex with Men Accessing Public Sex Environments in Chennai, India. ACTA ACUST UNITED AC 2009; 4:81-7. [DOI: 10.1080/15574090902913669] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- P. A. Newman
- a Factor-Inwentash Faculty of Social Work/Center for Applied Social Research , University of Toronto , Toronto , Ontario , Canada
| | - V. Chakrapani
- b Indian Network of People Living With HIV , Chennai , India
| | - C. Cook
- c Faculty of Social Work , University of Toronto , Toronto , Ontario , Canada
| | - M. Shunmugam
- d Social Welfare Association for Men (SWAM) , Chennai , India
| | - L. Kakinami
- e Division of Public Health , University of Rochester , Rochester , NY
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Abstract
OBJECTIVES To assess correlates of paid sex among men who have sex with men (MSM) in Chennai, India. METHODS A randomised survey was conducted among 200 MSM recruited from public sex environments using time-space sampling. The association of predictors with paid sex was assessed with chi(2) tests and multiple logistic regression. RESULTS Participants' mean age was 28.5 years (SD 8.7). Most (71.5%) were kothis; 60% had less than high school education and two-thirds had a monthly income less than 2000 Indian rupees. More than one-third (35.0%) reported daily/weekly harassment; 40.5% reported forced sex in the past year. The prevalence of paid sex was 59.5% (95% CI 52.7% to 66.3%). Univariate analyses indicated that paid sex was associated with kothi identity (chi(2) = 14.46; p<0.01), less than high school education (chi(2) = 4.79; p<0.05), harassment (chi(2) = 11.75; p<0.01) and forced sex (chi(2) = 3.98; p<0.05). Adjusted analyses revealed that paid sex was associated with kothi identity (adjusted odds ratio (AOR) 2.62, 95% CI 1.34 to 5.10) and harassment (AOR 2.34, 95% CI 1.16 to 4.72). MSM who engaged in paid sex (versus no paid sex) had a mean of 31 partners in the past month (versus 4, t = 6.17, p<0.001) and 71.2% used condoms consistently (versus 46.4%, chi(2) = 18.34; p<0.01). Overall, 32.5% were never tested for HIV. CONCLUSIONS Epidemic rates of harassment and sexual violence against MSM who engage in paid sex, predominantly kothis, suggest that interventions should target structural factors placing these men at increased risk of HIV/sexually transmitted infections and other health-compromising conditions. The effectiveness of individual-level, knowledge-based and condom-focused preventive interventions may be constrained in the context of poverty, low education, harassment and sexual violence.
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Affiliation(s)
- P A Newman
- University of Toronto, Centre for Applied Social Research, Faculty of Social Work, 246 Bloor Street West, Toronto, ON, Canada M5S1A1.
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Chakrapani V, Pendyala C, Kash K, Anderson AB, Sunkara MK, Angus JC. Electrochemical Pinning of the Fermi Level: Mediation of Photoluminescence from Gallium Nitride and Zinc Oxide. J Am Chem Soc 2008; 130:12944-52. [DOI: 10.1021/ja710999r] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Vidhya Chakrapani
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
| | - Chandrashekhar Pendyala
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
| | - Kathleen Kash
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
| | - Alfred B. Anderson
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
| | - Mahendra K. Sunkara
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
| | - John C. Angus
- Department of Chemical Engineering, Department of Physics, and Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, 44106, and Department of Chemical Engineering, University of Louisville, Louisville, Kentucky, 40292
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Chakrapani V, Angus JC, Anderson AB, Wolter SD, Stoner BR, Sumanasekera GU. Charge transfer equilibria between diamond and an aqueous oxygen electrochemical redox couple. Science 2007; 318:1424-30. [PMID: 18048683 DOI: 10.1126/science.1148841] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Undoped, high-quality diamond is, under almost all circumstances, one of the best insulators known. However, diamond covered with chemically bound hydrogen shows a pronounced conductivity when exposed to air. This conductivity arises from positive-charge carriers (holes) and is confined to a narrow near-surface region. Although several explanations have been proposed, none has received wide acceptance, and the mechanism remains controversial. Here, we report the interactions of hydrogen-terminated, macroscopic diamonds and diamond powders with aqueous solutions of controlled pH and oxygen concentration. We show that electrons transfer between the diamond and an electrochemical reduction/oxidation couple involving oxygen. This charge transfer is responsible for the surface conductivity and also influences contact angles and zeta potentials. The effect is not confined to diamond and may play a previously unrecognized role in other disparate systems.
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Chakrapani V, Balkin D, McGinn P. The effects of second phase additions (SiC, BaZrO3, BaSnO3) on the microstructure and superconducting properties of zone melt textured pBa2Cu3O7-x. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0964-1807(93)90383-d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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