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Sulania I, Tripathi A, Kabiraj D, Varma S, Avasthi DK. KeV ion-induced effective surface modifications on InP. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:4163-4167. [PMID: 19049195 DOI: 10.1166/jnn.2008.an13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In the present study, we have analyzed the changes in surface morphology leading to formation of periodic structures known as ripples which arise due to an interplay between sputtering and surface diffusion. The 1.5 keV Ar atoms with a flux of 14.8 mA/cm2 are used in the present study. The InP(100) samples were bombarded at an incidence angle of 45 degrees to the normal at a base pressure of 1 x 10(-6) Torr at room temperature with fluences varying from 4 x 10(16) to 3.2 x 10(17) atoms/cm2. The rippled InP(100) surface was characterized with AFM. An increase in the ripple wavelengths, from 60 nm to 150 nm with the fluence has been observed. The width of the ripples varies from 38 nm to 128 nm and ripple amplitude varies from 0.8 nm to 16 nm with increasing fluence. One can control the dimension of the ripples in nano scale by controlling the fluence. Scaling studies have been performed to understand the mechanism responsible for such kind of surface evolution. The roughness parameter, alpha was found to be between 0.65 to 0.75 and the growth parameter, beta, as 1.14 +/- 0.12. The XPS characterization has also been employed to study the changes in the behavior of the InP with varying fluence.
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Singh HB, Singh A, Tripathi A, Tiwari SK, Johri JK. Collar rot of Chlorophytum borivilianum caused by Corticium rolfsii: a new disease. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2338.2001.tb00977.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abraham J, Abreu P, Aglietta M, Aguirre C, Allard D, Allekotte I, Allen J, Allison P, Alvarez-Muñiz J, Ambrosio M, Anchordoqui L, Andringa S, Anzalone A, Aramo C, Argirò S, Arisaka K, Armengaud E, Arneodo F, Arqueros F, Asch T, Asorey H, Assis P, Atulugama BS, Aublin J, Ave M, Avila G, Bäcker T, Badagnani D, Barbosa AF, Barnhill D, Barroso SLC, Bauleo P, Beatty JJ, Beau T, Becker BR, Becker KH, Bellido JA, BenZvi S, Berat C, Bergmann T, Bernardini P, Bertou X, Biermann PL, Billoir P, Blanch-Bigas O, Blanco F, Blasi P, Bleve C, Blümer H, Bohácová M, Bonifazi C, Bonino R, Boratav M, Brack J, Brogueira P, Brown WC, Buchholz P, Bueno A, Burton RE, Busca NG, Caballero-Mora KS, Cai B, Camin DV, Caramete L, Caruso R, Carvalho W, Castellina A, Catalano O, Cataldi G, Cazon L, Cester R, Chauvin J, Chiavassa A, Chinellato JA, Chou A, Chye J, Clark PDJ, Clay RW, Colombo E, Conceição R, Connolly B, Contreras F, Coppens J, Cordier A, Cotti U, Coutu S, Covault CE, Creusot A, Criss A, Cronin J, Curutiu A, Dagoret-Campagne S, Daumiller K, Dawson BR, de Almeida RM, De Donato C, de Jong SJ, De La Vega G, de Mello Junior WJM, de Mello Neto JRT, DeMitri I, de Souza V, del Peral L, Deligny O, Della Selva A, Delle Fratte C, Dembinski H, Di Giulio C, Diaz JC, Dobrigkeit C, D'Olivo JC, Dornic D, Dorofeev A, dos Anjos JC, Dova MT, D'Urso D, Dutan I, DuVernois MA, Engel R, Epele L, Erdmann M, Escobar CO, Etchegoyen A, Facal San Luis P, Falcke H, Farrar G, Fauth AC, Fazzini N, Ferrer F, Ferry S, Fick B, Filevich A, Filipcic A, Fleck I, Fonte R, Fracchiolla CE, Fulgione W, García B, García Gámez D, Garcia-Pinto D, Garrido X, Geenen H, Gelmini G, Gemmeke H, Ghia PL, Giller M, Glass H, Gold MS, Golup G, Gomez Albarracin F, Gómez Berisso M, Gómez Herrero R, Gonçalves P, Gonçalves do Amaral M, Gonzalez D, Gonzalez JG, González M, Góra D, Gorgi A, Gouffon P, Grassi V, Grillo AF, Grunfeld C, Guardincerri Y, Guarino F, Guedes GP, Gutiérrez J, Hague JD, Hamilton JC, Hansen P, Harari D, Harmsma S, Harton JL, Haungs A, Hauschildt T, Healy MD, Hebbeker T, Hebrero G, Heck D, Hojvat C, Holmes VC, Homola P, Hörandel J, Horneffer A, Horvat M, Hrabovský M, Huege T, Hussain M, Iarlori M, Insolia A, Ionita F, Italiano A, Kaducak M, Kampert KH, Karova T, Kégl B, Keilhauer B, Kemp E, Kieckhafer RM, Klages HO, Kleifges M, Kleinfeller J, Knapik R, Knapp J, Koang DH, Krieger A, Krömer O, Kuempel D, Kunka N, Kusenko A, La Rosa G, Lachaud C, Lago BL, Lebrun D, Lebrun P, Lee J, Leigui de Oliveira MA, Letessier-Selvon A, Leuthold M, Lhenry-Yvon I, López R, Lopez Agüera A, Lozano Bahilo J, Luna García R, Maccarone MC, Macolino C, Maldera S, Mancarella G, Manceñido ME, Mandat D, Mantsch P, Mariazzi AG, Maris IC, Marquez Falcon HR, Martello D, Martínez J, Martínez Bravo O, Mathes HJ, Matthews J, Matthews JAJ, Matthiae G, Maurizio D, Mazur PO, McCauley T, McEwen M, McNeil RR, Medina MC, Medina-Tanco G, Meli A, Melo D, Menichetti E, Menschikov A, Meurer C, Meyhandan R, Micheletti MI, Miele G, Miller W, Mollerach S, Monasor M, Monnier Ragaigne D, Montanet F, Morales B, Morello C, Moreno JC, Morris C, Mostafá M, Muller MA, Mussa R, Navarra G, Navarro JL, Navas S, Necesal P, Nellen L, Newman-Holmes C, Newton D, Nguyen Thi T, Nierstenhoefer N, Nitz D, Nosek D, Nozka L, Oehlschläger J, Ohnuki T, Olinto A, Olmos-Gilbaja VM, Ortiz M, Ortolani F, Ostapchenko S, Otero L, Pacheco N, Pakk Selmi-Dei D, Palatka M, Pallotta J, Parente G, Parizot E, Parlati S, Pastor S, Patel M, Paul T, Pavlidou V, Payet K, Pech M, Pekala J, Pelayo R, Pepe IM, Perrone L, Petrera S, Petrinca P, Petrov Y, Pham Ngoc D, Pham Ngoc D, Pham Thi TN, Pichel A, Piegaia R, Pierog T, Pimenta M, Pinto T, Pirronello V, Pisanti O, Platino M, Pochon J, Privitera P, Prouza M, Quel EJ, Rautenberg J, Redondo A, Reucroft S, Revenu B, Rezende FAS, Ridky J, Riggi S, Risse M, Rivière C, Rizi V, Roberts M, Robledo C, Rodriguez G, Rodríguez Frías D, Rodriguez Martino J, Rodriguez Rojo J, Rodriguez-Cabo I, Ros G, Rosado J, Roth M, Rouillé-d'Orfeuil B, Roulet E, Rovero AC, Salamida F, Salazar H, Salina G, Sánchez F, Santander M, Santo CE, Santos EM, Sarazin F, Sarkar S, Sato R, Scherini V, Schieler H, Schmidt A, Schmidt F, Schmidt T, Scholten O, Schovánek P, Schüssler F, Sciutto SJ, Scuderi M, Segreto A, Semikoz D, Settimo M, Shellard RC, Sidelnik I, Siffert BB, Sigl G, Smetniansky De Grande N, Smiałkowski A, Smída R, Smith AGK, Smith BE, Snow GR, Sokolsky P, Sommers P, Sorokin J, Spinka H, Squartini R, Strazzeri E, Stutz A, Suarez F, Suomijärvi T, Supanitsky AD, Sutherland MS, Swain J, Szadkowski Z, Takahashi J, Tamashiro A, Tamburro A, Taşcău O, Tcaciuc R, Thomas D, Ticona R, Tiffenberg J, Timmermans C, Tkaczyk W, Todero Peixoto CJ, Tomé B, Tonachini A, Torres I, Torresi D, Travnicek P, Tripathi A, Tristram G, Tscherniakhovski D, Tueros M, Tunnicliffe V, Ulrich R, Unger M, Urban M, Valdés Galicia JF, Valiño I, Valore L, van den Berg AM, van Elewyck V, Vázquez RA, Veberic D, Veiga A, Velarde A, Venters T, Verzi V, Videla M, Villaseñor L, Vorobiov S, Voyvodic L, Wahlberg H, Wainberg O, Walker P, Warner D, Watson AA, Westerhoff S, Wieczorek G, Wiencke L, Wilczyńska B, Wilczyński H, Wileman C, Winnick MG, Wu H, Wundheiler B, Yamamoto T, Younk P, Zas E, Zavrtanik D, Zavrtanik M, Zech A, Zepeda A, Ziolkowski M. Upper limit on the diffuse flux of ultrahigh energy tau neutrinos from the Pierre Auger Observatory. PHYSICAL REVIEW LETTERS 2008; 100:211101. [PMID: 18518595 DOI: 10.1103/physrevlett.100.211101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Indexed: 05/26/2023]
Abstract
The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.
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Ghosh S, Tripathi A, Ganesan V, Avasthi DK. Synthesis of nanoscale copper nitride thin film and modification of the surface under high electronic excitation. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:2505-2508. [PMID: 18572674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nanoscale (approximately 90 nm) Copper nitride (Cu3N) films are deposited on borosilicate glass and Si substrates by RF sputtering technique in the reactive environment of nitrogen gas. These films are irradiated with 200 MeV Au15+ ions from Pelletron accelerator in order to modify the surface by high electronic energy deposition of heavy ions. Due to irradiation (i) at incident ion fluence of 1 x 10(12) ions/cm2 enhancement of grains, (ii) at 5 x 10912) ions/cm2 mass transport on the films surface, (iii) at 2 x 10(13) ions/cm2 line-like features on Cu3N/glass and nanometallic structures on Cu3N/Si surface are observed. The surface morphology is examined by atomic force microscope (AFM). All results are explained on the basis of a thermal spike model of ion-solid interaction.
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Tripathi A, Sinha A, Pandey OP, Sengupta SK. Lanthanum(Iii) and Praseodymium(Iii) Complexes of Carbohydrazones and Thiocarbohydrazones. ACTA ACUST UNITED AC 2008. [DOI: 10.1080/00945710009351753] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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81
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Lee J, Tripathi A. Measurements of Label Free Protein Concentration and Conformational Changes Using a Microfluidic UV-LED Method. Biotechnol Prog 2007; 23:1506-12. [DOI: 10.1021/bp0701970] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abraham J, Abreu P, Aglietta M, Aguirre C, Allard D, Allekotte I, Allen J, Allison P, Alvarez C, Alvarez-Muñiz J, Ambrosio M, Anchordoqui L, Andringa S, Anzalone A, Aramo C, Argirò S, Arisaka K, Armengaud E, Arneodo F, Arqueros F, Asch T, Asorey H, Assis P, Atulugama BS, Aublin J, Ave M, Avila G, Bäcker T, Badagnani D, Barbosa AF, Barnhill D, Barroso SLC, Bauleo P, Beatty J, Beau T, Becker BR, Becker KH, Bellido JA, BenZvi S, Berat C, Bergmann T, Bernardini P, Bertou X, Biermann PL, Billoir P, Blanch-Bigas O, Blanco F, Blasi P, Bleve C, Blümer H, Boháčová M, Bonifazi C, Bonino R, Boratav M, Brack J, Brogueira P, Brown WC, Buchholz P, Bueno A, Busca NG, Caballero-Mora KS, Cai B, Camin DV, Caruso R, Carvalho W, Castellina A, Catalano O, Cataldi G, Cazón-Boado L, Cester R, Chauvin J, Chiavassa A, Chinellato JA, Chou A, Chye J, Clark PDJ, Clay RW, Colombo E, Conceição R, Connolly B, Contreras F, Coppens J, Cordier A, Cotti U, Coutu S, Covault CE, Creusot A, Cronin J, Dagoret-Campagne S, Daumiller K, Dawson BR, de Almeida RM, De Donato C, de Jong SJ, De La Vega G, de Mello Junior WJM, de Mello Neto JRT, De Mitri I, de Souza V, del Peral L, Deligny O, Selva AD, Fratte CD, Dembinski H, Di Giulio C, Diaz JC, Dobrigkeit C, D'Olivo JC, Dornic D, Dorofeev A, Anjos JCD, Dova MT, D'Urso D, DuVernois MA, Engel R, Epele L, Erdmann M, Escobar CO, Etchegoyen A, Luis PFS, Falcke H, Farrar G, Fauth AC, Fazzini N, Fernández A, Ferrer F, Ferry S, Fick B, Filevich A, Filipčič A, Fleck I, Fonte R, Fracchiolla CE, Fulgione W, García B, García Gámez D, Garcia-Pinto D, Garrido X, Geenen H, Gelmini G, Gemmeke H, Ghia PL, Giller M, Glass H, Gold MS, Golup G, Albarracin FG, Berisso MG, Herrero RG, Gonçalves P, do Amaral MG, Gonzalez D, Gonzalez JG, González M, Góra D, Gorgi A, Gouffon P, Grassi V, Grillo A, Grunfeld C, Guardincerri Y, Guarino F, Guedes GP, Gutiérrez J, Hague JD, Hamilton JC, Hansen P, Harari D, Harmsma S, Harton JL, Haungs A, Hauschildt T, Healy MD, Hebbeker T, Heck D, Hojvat C, Holmes VC, Homola P, Hörandel J, Horneffer A, Horvat M, Hrabovský M, Huege T, Iarlori M, Insolia A, Ionita F, Italiano A, Kaducak M, Kampert KH, Keilhauer B, Kemp E, Kieckhafer RM, Klages HO, Kleifges M, Kleinfeller J, Knapik R, Knapp J, Koang DH, Kopmann A, Krieger A, Krömer O, Kümpel D, Kunka N, Kusenko A, La Rosa G, Lachaud C, Lago BL, Lebrun D, LeBrun P, Lee J, de Oliveira MAL, Letessier-Selvon A, Leuthold M, Lhenry-Yvon I, López R, Lopez Agüera A, Bahilo JL, Maccarone MC, Macolino C, Maldera S, Malek M, Mancarella G, Manceñido ME, Mandat D, Mantsch P, Mariazzi AG, Maris IC, Martello D, Martínez J, Bravo OM, Mathes HJ, Matthews J, Matthews JAJ, Matthiae G, Maurizio D, Mazur PO, McCauley T, McEwen M, McNeil RR, Medina MC, Medina-Tanco G, Meli A, Melo D, Menichetti E, Menschikov A, Meurer C, Meyhandan R, Micheletti MI, Miele G, Miller W, Mollerach S, Monasor M, Ragaigne DM, Montanet F, Morales B, Morello C, Moreno E, Moreno JC, Morris C, Mostafá M, Muller MA, Mussa R, Navarra G, Navarro JL, Navas S, Nellen L, Newman-Holmes C, Newton D, Thi TN, Nierstenhöfer N, Nitz D, Nosek D, Nožka L, Oehlschläger J, Ohnuki T, Olinto A, Olmos-Gilbaja VM, Ortiz M, Ostapchenko S, Otero L, Selmi-Dei DP, Palatka M, Pallotta J, Parente G, Parizot E, Parlati S, Pastor S, Patel M, Paul T, Pavlidou V, Payet K, Pech M, Pȩkala J, Pelayo R, Pepe IM, Perrone L, Petrera S, Petrinca P, Petrov Y, Ngoc D, Ngoc D, Thi TNP, Pichel A, Piegaia R, Pierog T, Pimenta M, Pinto T, Pirronello V, Pisanti O, Platino M, Pochon J, Porter TA, Privitera P, Prouza M, Quel EJ, Rautenberg J, Reucroft S, Revenu B, Rezende FAS, Řídký J, Riggi S, Risse M, Rivière C, Rizi V, Roberts M, Robledo C, Rodriguez G, Frías DR, Martino JR, Rojo JR, Rodriguez-Cabo I, Ros G, Rosado J, Roth M, Rouillé-d'Orfeuil B, Roulet E, Rovero AC, Salamida F, Salazar H, Salina G, Sánchez F, Santander M, Santo CE, Santos EM, Sarazin F, Sarkar S, Sato R, Scherini V, Schieler H, Schmidt F, Schmidt T, Scholten O, Schovánek P, Schüssler F, Sciutto SJ, Scuderi M, Segreto A, Semikoz D, Settimo M, Shellard RC, Sidelnik I, Siffert BB, Sigl G, De Grande NS, Smiałkowski A, šmída R, Smith AGK, Smith BE, Snow GR, Sokolsky P, Sommers P, Sorokin J, Spinka H, Squartini R, Strazzeri E, Stutz A, Suarez F, Suomijärvi T, Supanitsky AD, Sutherland MS, Swain J, Szadkowski Z, Takahashi J, Tamashiro A, Tamburro A, Taşcău O, Tcaciuc R, Thomas D, Ticona R, Tiffenberg J, Timmermans C, Tkaczyk W, Peixoto CJT, Tomé B, Tonachini A, Torresi D, Travnicek P, Tripathi A, Tristram G, Tscherniakhovski D, Tueros M, Tunnicliffe V, Ulrich R, Unger M, Urban M, Galicia JFV, Valiño I, Valore L, van den Berg AM, van Elewyck V, Vázquez RA, Veberič D, Veiga A, Velarde A, Venters T, Verzi V, Videla M, Villaseñor L, Vorobiov S, Voyvodic L, Wahlberg H, Wainberg O, Waldenmaier T, Walker P, Warner D, Watson AA, Westerhoff S, Wieczorek G, Wiencke L, Wilczyńska B, Wilczyński H, Wileman C, Winnick MG, Wu H, Wundheiler B, Xu J, Yamamoto T, Younk P, Zas E, Zavrtanik D, Zavrtanik M, Zech A, Zepeda A, Ziolkowski M. Correlation of the Highest-Energy Cosmic Rays with Nearby Extragalactic Objects. Science 2007; 318:938-43. [DOI: 10.1126/science.1151124] [Citation(s) in RCA: 560] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Kulriya PK, Singh F, Tripathi A, Ahuja R, Kothari A, Dutt RN, Mishra YK, Kumar A, Avasthi DK. Setup for in situ x-ray diffraction study of swift heavy ion irradiated materials. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2007; 78:113901. [PMID: 18052482 DOI: 10.1063/1.2804171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
An in situ x-ray diffraction (XRD) setup is designed and installed in the materials science beam line of the Pelletron accelerator at the Inter-University Accelerator Centre for in situ studies of phase change in swift heavy ion irradiated materials. A high vacuum chamber with suitable windows for incident and diffracted X-rays is integrated with the goniometer and the beamline. Indigenously made liquid nitrogen (LN2) temperature sample cooling unit is installed. The snapshots of growth of particles with fluence of 90 MeV Ni ions were recorded using in situ XRD experiment, illustrating the potential of this in situ facility. A thin film of C60 was used to test the sample cooling unit. It shows that the phase of the C60 film transforms from a cubic lattice (at room temperature) to a fcc lattice at around T=255 K.
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Mishra YK, Mohapatra S, Kabiraj D, Tripathi A, Pivin JC, Avasthi DK. Growth of Au nanostructures by annealing electron beam evaporated thin films. ACTA ACUST UNITED AC 2007. [DOI: 10.1088/1464-4258/9/9/s21] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Mohanty T, Batra Y, Tripathi A, Kanjilal D. Nanocrystalline SnO2 formation using energetic ion beam. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2007; 7:2036-40. [PMID: 17654987 DOI: 10.1166/jnn.2007.764] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Nanocrystalline tin oxide (SnO2) thin films grown by RF magnetron sputtering technique were characterized by UV-Visible absorption spectroscopy and Photoluminescence spectroscopy. From atomic force microscopic (AFM) and Glancing angle X-ray diffraction (GAXRD) measurements, the radius of grains was found to be approximately 6+/-2 nm. The thin films were bombarded with 250 keV Xe2+ ion beam to observe the stability of nanophases against radiation. For ion bombarded films, optical absorption band edge is shifted towards red region. Atomic force microscopy studies show that the radius of the grains was increased to approximately 8 +/- 1 nm and the grains were nearly uniform in size. The size of the grains has been reduced after ion bombardment in the case of films grown on Si. During this process, defects such as vacancies, voids were generated in the films as well as in the substrates. Ion bombardment induces local temperature increase of thin films causing melting of films. Ion beam induced defects enhances the diffusion of atoms leading to uniformity in size of grains. The role of matrix on ion beam induced grain growth is discussed.
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Kumar A, Avasthi DK, Pivin JC, Papaléo RM, Tripathi A, Singh F, Sulania I. Magnetic force microscopy of nano-size magnetic domain ordering in heavy ion irradiated fullerene films. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2007; 7:2201-5. [PMID: 17655018 DOI: 10.1166/jnn.2007.795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
In the present work, magnetic force microscopy is employed to investigate the magnetic ordering in ion irradiated fullerene films. It is observed that magnetic domain size is approximately 100-200 nm and magnetic signal is stronger at the domain boundaries. Magnetic signal arise in irradiated films is confirmed by magnetic measurements using a superconducting quantum interference device which increases with the ion fluence. The induced magnetism is possibly due to structural defects in the amorphous carbon phase formed by ion irradiation.
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Kumar M, Singh F, Khan SA, Tripathi A, Gupta A, Avasthi DK, Pandey AC. Swift heavy ion induced effects in LiF thin films. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/pssc.200673767] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schleimer R, Kato A, Tripathi A, Tancowny B, Suh L, Carter R, Agashe M, Harris K, Conley D, Kern R, Grammer L. B cell-activating Factor of the TNF Family (BAFF) Expression in Chronic Rhinosinusitis with Nasal Polyps. J Allergy Clin Immunol 2007. [DOI: 10.1016/j.jaci.2006.12.318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Truong-Tran A, Kern R, Conley D, Retsema S, Grammer L, Suh L, Tirumalasetty J, Tancowny B, Tripathi A, Schleimer R. Enhanced Expression of Innate Immune Genes in Chronic Rhinosinusitis. J Allergy Clin Immunol 2006. [DOI: 10.1016/j.jaci.2005.12.728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tripathi A, Tancowny B, Truong-Tran Q, Retsema S, Kern R, Conley D, Suh L, Schleimer R, Grammer L. Detection of Staphylococcus Aureus by Real-Time PCR in Chronic Rhinosinusitis with Nasal Polyps. J Allergy Clin Immunol 2006. [DOI: 10.1016/j.jaci.2005.12.285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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91
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Singh N, Qureshi A, Shah N, Rakshit A, Mukherjee S, Tripathi A, Avasthi D. Surface modification of polyethylene terephthalate by plasma treatment. RADIAT MEAS 2005. [DOI: 10.1016/j.radmeas.2005.01.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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92
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Clearfield A, Tripathi A, Medvedev D. In situX-ray study of hydrothermally prepared titanates and silicotitanates. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305099873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Wate S, Acharya N, Bhahada K, Vijay Y, Tripathi A, Avasthi D, Das D, Ghughre S. Positron annihilation lifetime and gas permeation studies of energetic ion-irradiated polycarbonate membranes. Radiat Phys Chem Oxf Engl 1993 2005. [DOI: 10.1016/j.radphyschem.2004.09.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Tripathi A, Conley D, Kern R, Seiberling K, Haines G, Huang J, Grammer L. Staphylococcal Superantigens and Eosinophilic Inflammation in Chronic Rhinosinusitis/Nasal Polyposis. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.1110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Bowyer J, Jones A, Damato B, Leach A, Shankar J, Tripathi A. The subjective experience of early postoperative pain following retrobulbar anaesthesia for enucleation and primary orbital implant. Orbit 2003; 22:271-7. [PMID: 14685901 DOI: 10.1076/orbi.22.4.271.17238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
INTRODUCTION We performed a prospective audit of the level of postoperative pain experienced by patients following enucleation with insertion of a primary orbital implant after preincisional regional retrobulbar anaesthesia using bupivacaine 0.75% with 1:100,000 adrenaline. MATERIALS AND METHODS An 11-point numerical ranking box scale was used to measure the subjective experience of postoperative pain following enucleation with insertion of a primary orbital implant in 40 patients with uveal melanoma. Surgery was performed under general anaesthesia with a supplementary peroperative retrobulbar injection of bupivacaine 0.75%/adrenaline 1:100,000. Pain scores were measured for the first 8 hours following administration of the block. RESULTS The sample included 19 female and 21 male patients with a mean age of 66.7 years (31-87). At four hours post block, 80% were still pain free with 17% experiencing only mild to moderate pain (BS-11 = 1-4). Thirty-four (85%), twenty-eight (70%) and twenty-seven (67%) patients remained pain free at 2, 3 and 4 hours, respectively with no additional analgesia. The remainder scored BS-11 of 1-4 in 92% of cases. Twenty percent required supplementary analgesia (paracetemol in 78% cases) by 5 hours and 57% by 8 hours. BS-11 at 8 hours were 0 in 50%, 1-4 in 22% and 5-10 in 10% of patients (17% asleep). No complications using this technique were recorded. DISCUSSION Using a preincisional retrobulbar injection of bupivacaine with adrenaline, BS-11 pain scores remained low with no or minimal additional analgesia for up to 4 hours post surgery. In combination with oral analgesia, effective pain control was provided in most cases for up to 8 hours post block.
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Bhattacharya N, Tripathi A, Dasgupta S, Sabbir MG, Roy A, Sengupta A, Roy B, Roychowdhury S, Panda CK. Association of deletion in the chromosomal 8p21.3-23 region with the development of invasive head & neck squamous cell carcinoma in Indian patients. Indian J Med Res 2003; 118:77-85. [PMID: 14680203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
BACKGROUND & OBJECTIVES Deletions in chromosome 8 (chr.8) have been shown to be necessary for the development of head and neck squamous cell carcinoma (HNSCC). Attempts have been made in this study to detect the minimal deleted region in chr.8 associated with the development of HNSCC in Indian patients and to study the association of clinicopathological features with the progression of the disease. METHODS The deletion mapping of chr.8 was done in samples from 10 primary dysplastic lesions and 43 invasive squamous cell carcinomas from the head and neck region of Indian patients to detect allelic alterations (deletion or size alteration) using 12 highly polymorphic microsatellite markers. The association of the highly deleted region was correlated with the tumour node metastasis (TNM) stages, nodal involvement, tobacco habit and human papilloma virus (HPV) infection of the samples. RESULTS High frequency (49%) of loss of heterozygosity (LOH) was seen within 13.12 megabase (Mb) region of chromosomal 8p21.3-23 region in the HNSCC samples, whereas the dysplastic samples did not show any allelic alterations in this region. The highest frequency (17%) of microsatellite size alterations (MA) was observed in the chr.8p22 region. The loss of short arm or normal copy of chr.8 and rare bi-allelic alterations were seen in the stage II-IV tumours (939, 5184, 2772, 1319 and 598) irrespective of their primary sites. The highly deleted region did not show any significant association with any of the clinical parameters. However, HPV infection was significantly associated (P < 0.05) with the differentiation grades and overall allelic alterations (LOH/MA) of the samples. INTERPRETATION & CONCLUSION Our data indicate that the 13.12 Mb deleted region in the chromosomal 8p21.3-23 region could harbour candidate tumour suppressor gene(s) (TSGs) associated with the progression anti invasion of HNSCC tumours in Indian patients.
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Abstract
AIMS The role of adjustable sutures in strabismus surgery has mainly been limited to conditions like dysthyroid restrictive myopathy, blow-out fractures of orbit, aberrant regeneration of nerves, and certain other long-standing and complicated squints. In this clinical study, an attempt has been made to analyse the efficacy of adjustable sutures in squint surgery as a routine procedure. We also studied patients' acceptability and satisfaction following this procedure and analysed various factors that may influence the surgical outcome (age, sex, previous surgeries, injections of botulinum toxin, etc). METHODS A total number of 443 patients, aged between 13 and 78 years, who underwent strabismus surgery in our department, from January 1996 to January 2000, were included in this study. Of these patients, 141 had surgery with adjustable sutures and 302 patients without adjustable sutures. Surgical results were followed up for a period ranging from 12 to 50 months. The main outcome measure was a need for a reoperation in the two groups. In addition, we also studied patients' satisfaction with regard to final cosmetic appearance or relief of diplopia; percentage change in angle of deviation in two groups, and influence of various factors such as age, sex, previous surgeries, and injection of botulinum toxin on the final surgical outcome. The results were statistically analysed using Levene's test for equality of variances, t-test for equality of means, and statistical significance of the results was analysed by calculating P-values. RESULTS In total, 8.51% of the patients in the adjustable group and 27.15% in the nonadjustable group needed a reoperation. Surgical results were found to be significantly better in patients who had adjustable sutures in comparison to those who did not have adjustable sutures (P<0.005). Patients' satisfaction and percentage change in angle of deviation was also much higher in adjustable sutures group. Age, sex, number of previous surgeries, previous injections of botulinum toxin, and type and amount of deviation had no statistically significant influence on the surgical outcome. CONCLUSIONS Strabismus surgery with adjustable sutures has a statistically significant better, final result than surgery without adjustable sutures. Patients' satisfaction and percentage change in angle of deviation is also much higher in the adjustable sutures group. As age, sex, number of previous surgeries, previous injections of botulinum toxin, and type and amount of deviation do not influence the final outcome, this type of surgery can be performed in virtually all types of patients.
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Mondal G, Tripathi A, Bhattacharya N, Sikdar N, Roy A, Sengupta A, Roy B, Panda CK, Roychoudhury S. Allelic imbalance at chromosome 11 in head and neck squamous cell carcinoma in an Indian patient population. J Clin Pathol 2003; 56:512-8. [PMID: 12835296 PMCID: PMC1769990 DOI: 10.1136/jcp.56.7.512] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2003] [Indexed: 12/14/2022]
Abstract
BACKGROUND Genetic instability of chromosome 11 is a frequent event in many solid tumours, including head and neck squamous cell carcinoma (HNSCC). AIMS To perform allelic imbalance analysis of cytogenetically mapped altered regions of human chromosome 11 in patients with HNSCC from eastern India. METHODS Genomic alterations were investigated using highly polymorphic microsatellite markers in both HNSCC and leukoplakia tissues. RESULTS Microsatellite markers D11S1758 from 11p13-15 and D11S925 from 11q23.3-24 had the highest frequency (38% and 32%, respectively) of loss of heterozygosity among all the markers analysed. Allelic loss at the marker D11S925 was seen in both leukoplakia and in all stages of HNSCC tumour tissues suggesting that it is an early event in HNSCC tumorigenesis. Microsatellite size alteration was also found to be high (> 20%) in several markers. In leukoplakia samples microsatellite instability was seen at a higher frequency than loss of the allele, indicating such alterations might initiate the process of tumorigenesis in HNSCC. CONCLUSIONS The high rate of chromosomal alterations at 11q21-24 in HNSCC suggests the presence of a putative tumour suppressor gene in this region.
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Tripathi A, Banerjee S, Roy A, Roychowdhury S, Panda CK. Alterations of the P16 gene in uterine cervical carcinoma from Indian patients. Int J Gynecol Cancer 2003; 13:472-9. [PMID: 12911724 DOI: 10.1046/j.1525-1438.2003.13330.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In our analysis, alterations in the P16 tumor suppressor gene were seen in 33% (15/46) of sampled uterine cervical lesions. Among the alterations, mutations in P16 were detected in 15% (7/46) of the samples. One mutation occurred at intron 1/exon 2 splice junction. All the other mutations were in exon 2 with three of them as silent mutations. The promoter hypermethylation and homozygous deletion of P16 gene were detected in 6.5% (3/46) and 8.7% (4/46) of the samples respectively. Loss of heterozygosity and microsatellite size alterations at the P16 locus were seen in 17% (8/46) of the samples. HPV16/18 infection was detected in 76% (35/46) of the samples. But no association was found between P16 alterations and HPV infection. Thus, it seems that P16 inactivation may be associated with the development of some uterine cervical carcinoma.
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Tripathi A, Dasgupta S, Roy A, Sengupta A, Roy B, Roychowdhury S, Panda CK. Sequential deletions in both arms of chromosome 9 are associated with the development of head and neck squamous cell carcinoma in Indian patients. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2003; 22:289-97. [PMID: 12866580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
In the deletion mapping of chromosome (chr) 9 in head and neck lesions of the Indian patient population by microsatellite markers, we have identified four discrete areas (D1-D4) with high loss of heterozygosities (LOHs) viz. 9p24-p23 (D1), 9p22-p21 (D2), 9q11-q13 (D3) and 9q22.3 (D4) regions. The deletions in D2 and D4 regions were suggested to be essential for the development of dysplastic lesions of head and neck, whereas the deletions in D1 and D3 regions were responsible for progression of the dysplastic lesions to early invasive head and neck squamous cell carcinoma (HNSCC). The microsatellite size alterations (MAs) were observed in the chromosomal 9pter-p23, 9p22-p21(D2), 9q13 and 9q21.1-q21.2 regions with gradual increase during progression of the tumor. Additional chromosomal alterations like loss of normal copy of chr.9 and biallelic alterations were also seen in our samples. There is a correlation between HPV infection with TNM stages, histopathological grades and LOHs at D1 and D4 regions. Whereas tobacco habit is associated with the occurrence of LOHs at D1 and LOHs / MAs at D2 region.
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