37 results on '"D. Jeyakumar"'
Search Results
2. S166: MAGROLIMAB IN COMBINATION WITH AZACITIDINE FOR PATIENTS WITH UNTREATED HIGHER-RISK MYELODYSPLASTIC SYNDROMES (HR MDS): 5F9005 PHASE 1B STUDY RESULTS
- Author
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D. A. Sallman, M. M. Al Malki, A. S. Asch, E. S. Wang, J. G. Jurcic, T. J. Bradley, I. W. Flinn, D. A. Pollyea, S. N. Kambhampati, T. N. Tanaka, J. F. Zeidner, G. Garcia-Manero, D. Jeyakumar, L. Gu, A. Tan, M. Chao, C. O’Hear, I. Lal, P. Vyas, and N. Daver
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2022
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3. P356: SUBGROUP ANALYSES OF KTE-X19, AN ANTI-CD19 CHIMERIC ANTIGEN RECEPTOR (CAR) T-CELL THERAPY, IN ADULT PATIENTS WITH RELAPSED OR REFRACTORY B-CELL ACUTE LYMPHOBLASTIC LEUKEMIA (R/R B-ALL) IN ZUMA-3
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B. D. Shah, R. D. Cassaday, J. H. Park, R. Houot, O. O. Oluwole, A. C. Logan, N. Boissel, T. Leguay, M. R. Bishop, M. S. Topp, D. Tzachanis, K. M. O’Dwyer, M. L. Arellano, Y. Lin, M. R. Baer, G. J. Schiller, M. Subklewe, M. Abedi, M. C. Minnema, W. G. Wierda, D. J. DeAngelo, P. Stiff, D. Jeyakumar, J. Dong, S. Adhikary, L. Zhou, P. C. Schuberth, B. Kharabi Masouleh, and A. Ghobadi
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2022
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- View/download PDF
4. P555: A PHASE 1B/2 STUDY OF THE CD123-TARGETING ANTIBODY-DRUG CONJUGATE PIVEKIMAB SUNIRINE (IMGN632) IN COMBINATION WITH VENETOCLAX (VEN) AND AZACITIDINE (AZA) FOR PATIENTS WITH CD123-POSITIVE AML
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N. G. Daver, P. Montesinos, A. Aribi, G. Martinelli, J. Altman, G. Roboz, E. S. Wang, P. W. Burke, D. Jeyakumar, R. B. Walter, D. J. DeAngelo, H. P. Erba, A. Advani, L. Gastaud, X. Thomas, E. Todisco, N. Pemmaraju, L. Mendez, A. de la Fuente, G. Gaidano, A. Curti, N. Boissel, C. Recher, C. Schliemann, P. Vyas, C. M. Sloss, J. Wang, K. A. Malcolm, P. A. Zweidler-McKay, and K. L. Sweet
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Published
- 2022
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5. Assessment on Performance and Emission Characteristics of the CRDI Engine Fueled with Ethanol/Diesel Blends in Addition to EGR
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C. Dineshkumar, P. D. Jeyakumar, C. K. Arvinda Pandian, N. Rajmohan, P. V. Elumalai, N. Kamesh, Saboor Shaik, Mohsen Sharifpur, and Nima Khalilpoor
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Chemical engineering ,TP155-156 - Abstract
In this research, the CRDI engine characteristics were analyzed with the aid of exhaust gas recirculation rate (EGR) adoption fueled with ethanol blends. The test fuels were the various blends with ethanol, such as (10% of ethanol + 90% of diesel) E10D90 (20% of ethanol + 80% of diesel), E20D80, and (30% of ethanol + 70% of diesel) E30D70. From the results, it was revealed that performance characteristics were reduced when using a higher concentration of the alcohols mixed with diesel fuel. The blend E30D70 showed that brake thermal efficiency (BTE) without EGR drops by 3.8%, increased by 9.14% of BSFC, a 9.25% decrease in oxides of nitrogen emissions, and slightly decreased CO and HC emissions compared to baseline diesel operation at 60% load condition. The blend E10D90 with 20% EGR shows the highest BTE of 8.87% when compared with base fuel, due to proper fuel mixture taking place in the inlet manifold. The results indicate that the engine runs smoothly, and E30D70 has chosen an optimum blend. A further experiment was performed using E30D70 with different rates of exhaust gas recirculation system. The addition of exhaust gas recirculation with E30D70 in the common rail diesel engine exhibits oxides of nitrogen emission, but in contrast, it was noticed to have inferior performance characteristics and drastically decreased HC and CO emissions. The hydrocarbon emission decreased E10D90, E20D80, and E30D70 at 60% load condition by 21.42%, 37.38%, and 48.76%, respectively. The blends E10D90, E20D80, and E30D70 decreased carbon dioxide by 7.9%, 30.08%, and 31.98%, respectively. The maximum reduction of NOx emission was observed at about 51.06% at an EGR rate of 20% with E30D70.
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- 2022
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6. Shape-tuned, surface-active and support-free silver oxygen reduction electrocatalyst enabled high performance fully non-PGM alkaline fuel cell
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Srinivasan Chandrasekaran, P. Anandha Ganesh, D. Jeyakumar, and A. N. Prakrthi
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Tafel equation ,Alkaline fuel cell ,Potassium hydroxide ,Materials science ,Ion exchange ,Reducing agent ,General Chemical Engineering ,Limiting current ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,0210 nano-technology - Abstract
Exploring non-platinum group metal (n-PGM) based efficient oxygen reduction reaction (ORR) electro-catalysts is highly important for realizing advancement in sustainable next generation-alkaline anion exchange membrane fuel cells (AAEMFCs). Herein, we demonstrate a new “hierarchical shape tuning approach” for the synthesis of controlled sized and shaped non-PGM based Ag ORR electro-catalysts with surface active nano-islands. Hierarchical shapes ranging from spherical (S-AgNs), worm-in-sphere, sphere-in-worm and vermiform (worm-like) Ag nanostructures (V-AgNs) were obtained by precisely varying the ratios of capping agent to dual reducing agents in water at ambient conditions. Compared to S-AgNs, V-AgNs revealed a higher mass normalized ORR Tafel activity (0.303 A mgAg−1 at 0.9 V), onset (1.06 V) and half wave (0.78 V) potentials and higher retention of limiting current density (>88%) after 5000 cycles in 0.5 M potassium hydroxide (KOH) solution attributable to their unique worm like morphology with surface active nano-islands and support free-nature enabled better catalyst utilization. In a fully “non-PGM AAEMFC” (n-PAAEMFC), V-AgNs exhibited the highest fuel cell activity of 115.6 mW cm−2 and stable short-term durability (∼240 h) compared to S-AgNs (41.3 mW cm−2) and previously reported fully n-PAAEMFCs indicating their potential use in next-generation alkaline fuel cells.
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- 2021
7. Corrigendum: Nano‐Porous Electro‐Catalyst with Textured Surface Active Pd‐Pt Islands for Efficient Methanol Tolerant Oxygen Reduction Reaction
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P. Anandha Ganesh and D. Jeyakumar
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General Chemistry - Published
- 2021
8. ESTIMATION AND VALIDATION OF INTERFACIAL HEAT TRANSFER COEFFICIENT DURING SOLIDIFICATION OF SPHERICAL SHAPED ALUMINUM ALLOY (AL 6061) CASTING USING INVERSE CONTROL VOLUME TECHNIQUE
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L. Anna Gowsalya, R. Rajaraman, Ramalingam Velraj, and P. D. Jeyakumar
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Materials science ,Alloy ,General Engineering ,General Physics and Astronomy ,chemistry.chemical_element ,Fluid mechanics ,Heat transfer coefficient ,engineering.material ,Volume (thermodynamics) ,chemistry ,Casting (metalworking) ,Aluminium ,Mass transfer ,engineering ,General Materials Science ,Composite material ,Thermal fluids - Published
- 2019
9. Performance of cross-linked polymers based gel electrolyte in the fabrication of quasi-solid state dye-sensitized solar cells
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A. Arulraj, P. Anbarasu, K. Rajendran, V. Sannasi, M. Kesavan, D. Jeyakumar, and Mohan Ramesh
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010302 applied physics ,chemistry.chemical_classification ,Acrylate ,Materials science ,Mechanical Engineering ,Cross-link ,technology, industry, and agriculture ,Ether ,02 engineering and technology ,Polymer ,Electrolyte ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,chemistry.chemical_compound ,Dye-sensitized solar cell ,chemistry ,Chemical engineering ,Mechanics of Materials ,0103 physical sciences ,General Materials Science ,0210 nano-technology ,Quasi-solid ,Ethylene glycol - Abstract
Cross-linked polymer (CLP) composed of poly(ethylene glycol) methyl ether acrylate and poly(ethylene glycol) diacrylate has been used in synthesizing gel electrolyte. A set of electrolyte samples was synthesized using gel casting method by varying the weight percentage ratio of cross-linked polymers from 2–14 % in an incremental order (2 %) with respect to poly (ethylene oxide) (PEO) and evaluated its performance by employing in the fabrication of dye-sensitized solar cells. The synthesized polymer was subjected to different analytical techniques such as NMR, TGA, DSC, GPC, and FTIR to confirm the materials. The molecular weight of the CLP has been measured using GPC and the obtained value is found to be 3.655 KDa with polydispersity of 1.94. The CLP-PEO gel electrolyte with 10 % weight ratio has obtained the highest ionic conductivity of 3.07 × 10−6 S/cm−1 at room temperature and best photo-conversion efficiency of 5.1 % was achieved for the same.
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- 2018
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10. White light emission in alkali metal ion co-doped single host lattice phosphor Sr3B2O6:Ce3+,Eu2+,A+ [A=Li, Na and K]
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D. Jeyakumar, Paulraj Arunkumar, S. Sekar, and Narayanan Lakshminarasimhan
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Diffraction ,Materials science ,Photoluminescence ,Infrared ,Process Chemistry and Technology ,Analytical chemistry ,Phosphor ,Alkali metal ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Ion ,Materials Chemistry ,Ceramics and Composites ,Diffuse reflection ,Spectroscopy - Abstract
White light emitting alkali metal ion co-doped single host lattice phosphors Sr 2.955 B 2 O 6 :0.02Ce 3+ , 0.005Eu 2+ , 0.02A + [A=Li, Na and K] were synthesized by high temperature solid state reaction. The synthesized phosphors were characterized by powder X-ray diffraction and Fourier transform infrared spectroscopic techniques. The optical properties were studied using diffuse reflectance UV–vis reflectance spectroscopy and photoluminescence (PL) spectroscopy. The role of Ce 3+ as a sensitizer of Eu 2+ was found from PL excitation results. The PL white light emission depends on the nature of co-doped alkali metal ion charge compensator.
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- 2015
11. Synthesis and optical properties of poly(2,7-(9,9-dihexylfluorene)-3,3′(4,4′-dialkoxybiphenyl))
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Tini P. Jose, D. Jeyakumar, and V. Sannasi
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chemistry.chemical_classification ,Thermogravimetric analysis ,Photoluminescence ,Materials science ,Polymers and Plastics ,Annealing (metallurgy) ,General Chemical Engineering ,General Chemistry ,Polymer ,Gel permeation chromatography ,chemistry ,Chemical engineering ,Polymer chemistry ,Materials Chemistry ,Thin film ,Glass transition ,Alkyl - Abstract
Five new polymers were synthesized by Suzuki coupling reaction using 9,9-dihexylfluorene-2,7-diboronic acid and 3,3′-dibromo-4,4′-dialkoxybiphenyl as the starting materials. The synthesized alternating copolymers were characterized using gel permeation chromatography, 1H and 13C NMR, FT-IR, optical absorption and emission spectroscopic techniques. The thermal behavior of these polymers was analyzed using thermal gravimetric analysis and temperature modulated differential scanning calorimetric studies. The thermal studies show all the polymers were stable up to 300 °C and the glass transition temperature depends on the alkyl chain length. All the polymers have absorption around 330 nm in solution as well as in film, whereas the polymers have emission around 390 nm in both solution and film. Absorption and emission properties of the synthesized materials are not significantly different in solution, but are dramatically different as thin films at different annealing temperatures.
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- 2014
12. Synthesis of porphyrin-appended poly(fluorene-alt-carbazole): photoluminescent and electrochemical studies
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V. Sannasi and D. Jeyakumar
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chemistry.chemical_classification ,Quenching (fluorescence) ,Photoluminescence ,Materials science ,Polymers and Plastics ,Carbazole ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,Polymer ,Fluorene ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Porphyrin ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Tetraphenylporphyrin ,Polymer chemistry ,Materials Chemistry ,0210 nano-technology ,Absorption (electromagnetic radiation) - Abstract
Poly(fluorene-alt-carbazole) appended with meso-tetraphenylporphyrin (MTPPC) linked through oxyethylene spacer and the parent poly(N-hexyl-2,7-carbazole-alt-9,9-di-n-hexyl fluorene) (P1) were synthesized and characterized. Optical absorption properties of the polymers containing 5% of MTPPC (P2) and 10% of MTPPC (P3) in the polymer backbone show extended optical absorption toward long wavelength compared to the parent polymer P1. Optical absorption studies of the polymers showed that polymer P1 has absorption at 384 nm in solution, whereas polymers P2 and P3 have absorption at 384 nm corresponding to polymer backbone and soret band at 421 nm with Q bands at around 518 and 554 nm in solution. P1 shows photoluminescence emission around 417 nm, whereas P2 and P3 fall around 656 nm. Thermal, electrochemical, and quenching studies of the polymers have been studied and the details are reported.
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- 2016
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13. Synergistic interaction of treatment and blending on the stability of high-density polyethylene
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G. Suresh, Doble Mukesh, and D. Jeyakumar
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Chromium ,Weight loss ,Materials science ,Oxygenated compounds ,Polymers and Plastics ,Polymers ,Starch ,UV treatment ,chemistry.chemical_element ,Mechanical properties ,Thermal treatment ,Low molecular weight ,Metal-polymer complexes ,Star polymers ,Synergistic interaction ,Degradation ,chemistry.chemical_compound ,Polymer chemistry ,Materials Chemistry ,Chlorine ,Thermoplastics ,High density polyethylenes ,Metal ions ,Potato starch ,chemistry.chemical_classification ,Potato starches ,Mass spectrometry ,Treatment conditions ,Additives ,food and beverages ,General Chemistry ,Polymer ,Polyethylene ,Blending ,Waste disposal ,Hydrocarbons ,Waste treatment ,Surfaces, Coatings and Films ,chemistry ,High-density polyethylene ,Nuclear chemistry - Abstract
Degradation of high-density polyethylene (HDPE) films blended with 0.5, 1.0, and 2.0% metal ions (MIs, chromium = 36%, silicon = 8%, aluminum = 4%, and chlorine = 2%) and 5, 10, and 20% potato starch were studied under two different abiotic treatment conditions (they were either heated to 70�C or exposed to UV at 300-400 nm) for a period of 100 days. The addition of metals did not affect the mechanical strength of the polymer, whereas starch blending did. The latter turned the polymer yellow. HDPE with MIs exhibited higher levels of oxidation than the other samples. UV treatment affected the mechanical strength of the MI-blended HDPE more than the other additive or the thermal treatment. The formation of extractable oxygenated compounds and unoxidized low-molecular-weight hydrocarbons increased with increasing concentration of additives in HDPE. The surface energy in all cases increased, this indicated that the polymers turned hydrophilic. The maximum weight loss (28%) was seen in the 2% MI-blended HDPE exposed to UV followed by the 20% starch-blended polymer exposed to heat (24%). These results indicate a synergy between blending and the treatment strategy, this also suggests an optimal waste-disposal strategy. � 2012 Wiley Periodicals, Inc.
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- 2012
14. Structure–property relations in hexagonal and monoclinic BiPO4:Eu3+nanoparticles synthesized by polyol-mediated method
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Narayanan Lakshminarasimhan, D. Jeyakumar, Paulraj Arunkumar, and C. Jayajothi
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Materials science ,General Chemical Engineering ,Hexagonal phase ,chemistry.chemical_element ,General Chemistry ,Crystal structure ,Nanocrystalline material ,Bismuth ,symbols.namesake ,Crystallography ,chemistry ,Phase (matter) ,symbols ,Isostructural ,Raman spectroscopy ,Monoclinic crystal system - Abstract
Hexagonal BiPO4·xH2O and Bi0.95Eu0.05PO4·xH2O nanoparticles were synthesized by a polyol-mediated method employing diethylene glycol. The powder X-ray diffraction revealed the phase purity and isostructural nature of both undoped and Eu3+-doped BiPO4. The monoclinic Bi0.95Eu0.05PO4 was obtained by heating the hexagonal Bi0.95Eu0.05PO4·xH2O at 600 °C. The microscopical characterization revealed the formation of nanocrystalline materials. Water molecules present in the bismuth precursor favoured the formation of hexagonal phase at low temperature. The role of DEG molecules in arresting the particle growth during the phase transformation of Bi0.95Eu0.05PO4 from hexagonal to monoclinic was observed. The synthesized materials were characterized using different spectroscopic techniques such as FT-IR, Raman, 31P MAS-NMR, DRUV-Vis and PL. The difference in the crystal structures and symmetries is clearly reflected in the spectral results of hexagonal and monoclinic Bi0.95Eu0.05PO4. The structure-property relations were studied to derive its importance from both fundamental and technological aspects.
- Published
- 2012
15. Performance of dye-sensitized solar cells employing polymer gel as an electrolyte and the influence of nano-porous materials as fillers
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M. Kesavan, A. Arulraj, P. Anbarasu, Mohan Ramesh, D. Jeyakumar, K. Rajendran, and P. Anandha Ganesh
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Materials science ,Polymers and Plastics ,Metals and Alloys ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Biomaterials ,Nano porous ,Dye-sensitized solar cell ,Chemical engineering ,Polymer gel ,0210 nano-technology - Published
- 2018
16. Synthesis and characterization of nanosized titanium dioxide and silicon dioxide for corrosion resistance applications
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K. Maruthan, M. Selvaraj, D. Jeyakumar, and A.M. Kamalan Kirubaharan
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chemistry.chemical_classification ,Nanocomposite ,Materials science ,Silicon dioxide ,technology, industry, and agriculture ,Surfaces and Interfaces ,General Chemistry ,engineering.material ,Surfaces, Coatings and Films ,Dielectric spectroscopy ,Corrosion ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Coating ,Silicone resin ,Titanium dioxide ,engineering ,Interpenetrating polymer network ,Composite material - Abstract
We are reporting the preparation and characterization of nano-titanium dioxide and silica. The corrosion resistance performance of these nanopigments in silicone as well as silicone–polypyrrole Interpenetrating Polymer Network has been evaluated by impedance spectroscopy. The capacitance and resistance exerted by this nanocomposite coating were compared with the microcomposite coating and found that the nanocomposite coatings has the resistance in the order of 108 Ω cm2 in 3% sodium chloride solution, which is more than the microcomposite coating. The comparison of heat resistance performance of these composite coatings indicates that nanocomposite coatings exhibit higher heat resistance property than the microcomposite coatings.
- Published
- 2009
17. Steady state analysis of a bulk queue with multiple vacations, setup times with N-policy and closedown times
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S.b d Jeyakumar and R. Arumuganathan
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Discrete mathematics ,Computer science ,M/G/k queue ,Applied Mathematics ,M/D/1 queue ,Real-time computing ,M/D/c queue ,G/G/1 queue ,Modelling and Simulation ,Modeling and Simulation ,Batch processing ,Batch production ,Bulk queue ,Queue - Abstract
In this paper a M X / G ( a , b )/1 queueing system with multiple vacations, setup time with N -policy and closedown times is considered. On completion of a service, if the queue length is ξ , where ξ a , then the server performs closedown work. Following closedown the server leaves for multiple vacations of random length irrespective of queue length. When the server returns from a vacation and if the queue length is still less than ‘ N ’, he leaves for another vacation and so on, until he finds ‘ N ’ ( N > b ) customers in the queue. That is, if the server finds at least ‘ N ’ customers waiting for service, then he requires a setup time ‘ R ’ to start the service. After the setup he serves a batch of ‘ b ’ customers, where b ⩾ a . Various characteristics of the queueing system and a cost model with the numerical solution for a particular case of the model are presented.
- Published
- 2005
18. Stage separation dynamic analysis of upper stage of a multistage launch vehicle using retro rockets
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D. Jeyakumar, B. Nageswara Rao, and K. K. Biswas
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Numerical analysis ,Separation (aeronautics) ,Relative velocity ,Equations of motion ,Collision ,Computer Science Applications ,Runge–Kutta methods ,Control theory ,Modelling and Simulation ,Modeling and Simulation ,Retrorocket ,Stage (hydrology) ,Algorithm ,Mathematics - Abstract
This paper presents in brief the formulation used for the studies of lateral and longitudinal dynamics associated with separation and pull out of an ongoing functional stage from the spent stage of a multistage launch vehicle using retro rockets as jettisoning system. A fourth-order Runge-Kutta method is employed to solve the governing nonlinear differential equations of motion to obtain the state vectors of the separating bodies. A statistical method is adapted to account for the off nominal design parameters of the bodies undergoing separation and the jettisoning system. The tolerances in magnitude of the pull out time, relative velocity, lateral gap and longitudinal clearances between the separating bodies were used to find out the nonoccurrence of collision between the separating bodies. This procedure helps in designing and adapting a suitable jettisoning system to achieve collision free separation of multistage launch vehicle stages.
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- 2005
19. Molecular diagnosis and antifungal susceptibility profiles of rare isolates of filamentous fungi among patients with cancer from South India
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R. Baskar, K. Umamaheswari, D. Jeyakumar, and M. Alli
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Antifungal ,Microbiology (medical) ,Infectious Diseases ,medicine.drug_class ,medicine ,Cancer ,General Medicine ,Biology ,medicine.disease ,Microbiology - Published
- 2016
- Full Text
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20. High Temperature Processable Flexible Polymer Films
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A. Sivanantha Raja, C. Sanjeeviraja, D. Jeyakumar, and D. Shanmuga Sundar
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Materials science ,Bioengineering ,02 engineering and technology ,Substrate (electronics) ,Flexible organic light-emitting diode ,chemistry.chemical_compound ,0202 electrical engineering, electronic engineering, information engineering ,Transmittance ,General Materials Science ,Electrical and Electronic Engineering ,chemistry.chemical_classification ,Polydimethylsiloxane ,business.industry ,020206 networking & telecommunications ,Polymer ,Conformable matrix ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Flexible electronics ,Computer Science Applications ,chemistry ,Optoelectronics ,Orthosilicate ,0210 nano-technology ,business ,Biotechnology - Abstract
Recent developments in the field of flexible electronics motivated the researchers to start working in verdict of new flexible substrate for replacing the existing rigid glass and flexible plastics. Flexible substrates offer significant rewards in terms of being able to fabricate flexible electronic devices that are robust, thinner, conformable, lighter and can be rolled away when needed. In this work, a new flexible and transparent substrate with the help of organic materials such as Polydimethylsiloxane (PDMS) and tetra ethoxy orthosilicate (TEOS) is synthesized. Transmittance of about 90–95% is acquired in the visible region (400–700[Formula: see text]nm) and the synthesized substrate shows better thermal characteristics and withstands temperature up to 200[Formula: see text]C without any significant degradation. Characteristics such as transmittance ([Formula: see text]), absorption ([Formula: see text]), reflectance ([Formula: see text]), refractive index ([Formula: see text]) and extinction coefficient ([Formula: see text]) are also reported.
- Published
- 2016
21. Cyclic voltammetric measurements of growth of Aspergillus terreus
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Sreenath Subrahmanyam, T. V. Subramanian, D. Jeyakumar, Narendran Kodandapani, Karunakaran Moovarkumuthalvan, and Kumaran Shanmugam
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Measurement method ,biology ,Stereochemistry ,Metabolite ,Analytical chemistry ,Peak current ,Growth curve (biology) ,biology.organism_classification ,Electrochemistry ,Analytical Chemistry ,Culture Media ,chemistry.chemical_compound ,Aspergillus ,chemistry ,Phase (matter) ,Aspergillus terreus ,Biomass ,Cyclic voltammetry - Abstract
A detailed study using the cyclic voltammogram was done on the live cells of Aspergillus terreus. The peak current values were obtained for different days of growth and plotted against time. The response of cyclic voltammogram showed the phases of the growth of the fungus. The growth curve obtained matched well with the conventional methodology, which assesses the increase of dry weight of the organisms against time. The electrochemical method is more advantageous because it is easy to assess and consumes less time. Further the electrochemical method clearly shows the decline phase which is generally not very defined in the conventional method of assessment of the growth curve. It was confirmed by further experiments that the metabolites were responsible for the anodic peak and not the biomass. Further work is in progress in order to analyze the metabolite(s) that is/are responsible for the anodic peak.
- Published
- 2002
22. Functionalization of graphene with nitrogen using ethylenediaminetetraacetic acid and their electrochemical energy storage properties
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N. Ilayaraja, T. K. Shruthi, Marappan Sathish, and D. Jeyakumar
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Materials science ,Graphene ,General Chemical Engineering ,Inorganic chemistry ,Oxide ,Ethylenediaminetetraacetic acid ,General Chemistry ,Electrochemistry ,Capacitance ,law.invention ,chemistry.chemical_compound ,chemistry ,X-ray photoelectron spectroscopy ,law ,Surface modification ,Graphene oxide paper - Abstract
Recently there has been a considerable focus on the synthesis of nitrogen functionalized graphene for energy storage and conversion. Herein, we report a simple, economical and facile process for the synthesis of nitrogen containing graphene composite which can be scaled up for mass production by using a nitrogen containing organic compound, ethylenediaminetetraacetic acid (EDTA) and graphene oxide as precursors. From the XRD studies, the increase in the interlayer distance between the graphene sheets confirms the functionalization of graphene sheets and the FT-IR spectroscopic analysis revealed the presence of N-containing functional groups in N-doped graphene sheets. XPS analysis confirms the chemical nature of N-containing functional groups, and TG analysis showed the amount of EDTA loaded on the graphene sheets. This composite exhibits a large specific capacitance of 290 F g−1 at 0.1 A g−1 with a capacitance retention of 67% and 58% at high current densities of 10 and 20 A g−1, respectively, thereby showing superior rate capability. In addition, it showed long-term electrochemical stability through 6000 charge–discharge cycles even at a high current density of 5 A g−1 with a specific capacitance loss of 2%.
- Published
- 2014
23. Amperometric Biochemical Characterization of Isolated Fungal Strains
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Narendran Kodandapani, Kumaran Shanmugam, D. Jeyakumar, Sreenath Subrahmanyam, T. V. Subramanian, Balu Ranganathan, and Ahamarshan Jayaraman Nagarajan
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Centre for Ecological Sciences ,biology ,Chemistry ,urogenital system ,food and beverages ,Assimilation (biology) ,Fungus ,biology.organism_classification ,Amperometry ,Analytical Chemistry ,carbohydrates (lipids) ,Biochemistry ,parasitic diseases ,Electrochemistry ,lipids (amino acids, peptides, and proteins) ,Biosensor - Abstract
The identification and biochemical characterization of microbial species by electrochemical methods have helped to develop microbial sensors that are rapid and effective. In this article, we present results of biochemical characterization of five fungi, the assimilation and biochemical characterization of various substrates and tolerance to selected inhibitors. The results are based on the respiratory rate and assimilatory profile of these fungi and are more rapid and reliable. The experimental results are discussed here with reference to individual fungus. Further, the advantages of the electrochemical assimilation for the biochemical characterization of the microbes have been discussed.
- Published
- 2001
24. Nano silicon carbide: a new lithium-insertion anode material on the horizon
- Author
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D. Jeyakumar, T. Sri Devi Kumari, and T. Prem Kumar
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Materials science ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,Chemical vapor deposition ,Electrochemistry ,Anode ,Carbide ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Nano ,Silicon carbide ,Lithium ,Nano silicon - Abstract
Bulk-synthesized silicon carbide, hitherto considered inactive for electrochemical lithium insertion, is demonstrated as a potential high-capacity, long-cycling anode material for lithium-ion batteries. In this study, we show that cubic (3C polytype) nano SiC, prepared by a chemical vapour deposition (CVD) method, delivers a reversible lithium insertion capacity of about 1200 mA h g−1 over 200 cycles.
- Published
- 2013
25. Electrochemical study of the nonaqueous oxidation of dipyrrolic compounds
- Author
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Hani D. Tabba, P. M. S. Neves, Maria Graça, Kevin M. Smith, José A. S. Cavaleiro, and D. Jeyakumar
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Chemistry ,Organic Chemistry ,Inorganic chemistry ,Electrochemistry - Published
- 1989
26. Extending duration of letermovir prophylaxis in haploidentical stem cell transplantation.
- Author
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Vittayawacharin P, Lee BJ, Griffin S, Doh J, Smith J, Nam H, Blodget E, Jeyakumar D, Kongtim P, and Ciurea SO
- Abstract
Not available.
- Published
- 2024
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27. Impact of prior therapies and subsequent transplantation on outcomes in adult patients with relapsed or refractory B-cell acute lymphoblastic leukemia treated with brexucabtagene autoleucel in ZUMA-3.
- Author
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Shah BD, Cassaday RD, Park JH, Houot R, Oluwole OO, Logan AC, Boissel N, Leguay T, Bishop MR, Topp MS, Tzachanis D, O'Dwyer KM, Arellano ML, Lin Y, Baer MR, Schiller GJ, Subklewe M, Abedi M, Minnema MC, Wierda WG, DeAngelo DJ, Stiff PJ, Jeyakumar D, Mao D, Adhikary S, Zhou L, Schuberth PC, Damico Khalid R, and Ghobadia A
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- Humans, Adult, Immunotherapy, Adoptive, Adaptor Proteins, Signal Transducing, Antigens, CD19, Cytokine Release Syndrome, Hematopoietic Stem Cell Transplantation, Precursor Cell Lymphoblastic Leukemia-Lymphoma therapy
- Abstract
Background: Brexucabtagene autoleucel (brexu-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved in the USA for adults with relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) and in the European Union for patients ≥26 years with R/R B-ALL. After 2 years of follow-up in ZUMA-3, the overall complete remission (CR) rate (CR+CR with incomplete hematological recovery (CRi)) was 73%, and the median overall survival (OS) was 25.4 months in 78 Phase 1 and 2 patients with R/R B-ALL who received the pivotal dose of brexu-cel. Outcomes by prior therapies and subsequent allogeneic stem cell transplantation (alloSCT) are reported., Methods: Eligible adults had R/R B-ALL and received one infusion of brexu-cel (1×10⁶ CAR T cells/kg) following conditioning chemotherapy. The primary endpoint was the CR/CRi rate per central review. Post hoc subgroup analyses were exploratory with descriptive statistics provided., Results: Phase 1 and 2 patients (N=78) were included with median follow-up of 29.7 months (range, 20.7-58.3). High CR/CRi rates were observed across all prior therapy subgroups examined: 1 prior line of therapy (87%, n=15) and ≥2 prior lines (70%, n=63); prior blinatumomab (63%, n=38) and no prior blinatumomab (83%, n=40); prior inotuzumab (59%, n=17) and no prior inotuzumab (77%, n=61); and prior alloSCT (76%, n=29) and no prior alloSCT (71%, n=49). The frequency of Grade ≥3 cytokine release syndrome, neurological events, and treatment-related Grade 5 adverse events were largely similar among prior therapy subgroups.Median duration of remission (DOR) in responders with (n=14) and without (n=43) subsequent alloSCT was 44.2 (95% CI, 8.1 to not estimable (NE)) and 18.6 months (95% CI, 9.4 to NE); median OS was 47.0 months (95% CI, 10.2 to NE) and not reached (95% CI, 23.2 to NE), respectively. Median DOR and OS were not reached in responders without prior or subsequent alloSCT (n=22)., Conclusions: In ZUMA-3, adults with R/R B-ALL benefited from brexu-cel, regardless of prior therapies and subsequent alloSCT status, though survival appeared better in patients without certain prior therapies and in earlier lines of therapy. Additional studies are needed to determine the impact prior therapies and subsequent alloSCT have on outcomes of patients who receive brexu-cel., Competing Interests: Competing interests: BS reports honoraria from Acrotech Biopharma, BeiGene, Gilead Sciences, Janssen, Pharmacyclics, and Spectrum; consulting/advisory role for Adaptive Biotechnologies; Amgen; Celgene/BMS; Kite, a Gilead Company; Novartis; Pfizer; and Precision BioSciences; research funding from Gilead Sciences, Incyte, Jazz Pharmaceuticals, and Kite; and travel support from Celgene, Janssen, Kite, Novartis, Pfizer, Seattle Genetics, and Stemline Therapeutics. RC reports spouse employment with Seagen; stock or other ownership in Seagen; honoraria from Amgen, Autolus (board member), PeproMene Bio (board member), Pfizer, and Kite; consultancy/advisory role for Amgen and Jazz; and research funding from Pfizer, Merck, Amgen, Servier, Kite, and Vanda. JHP reports consulting/advisory role for AstraZeneca, Kite, and Novartis and research funding from Amgen, Genentech, and Juno. RH reports honoraria from ADC therapeutics, Bristol Myers Squibb, Celgene, Gilead Sciences, Janssen, Kite, MSD, Novartis, and Roche; and consulting/advisory role for Kite/Gilead. OOO reports consulting/advisory role for Pfizer, Kite, Gilead, AbbVie, Janssen, TG Therapeutics, ADC, Novartis, Epizyme, Curio Science, Nektar, and Syncopation; research funding from Kite, Pfizer, Daiichi Sankyo, and Allogene; and honoraria from Pfizer and Gilead. ACL reports consulting/advisory role for AbbVie, Bristol Myers Squibb, and Pfizer; research funding from Amgen, Amphivena, Astellas, Autolus, Jazz, Kadmon, Kite, and Pharmacyclics. NB reports honoraria from and consulting/advisory role for Gilead Sciences. TL reports consultancy/advisory role for Amgen and Servier. MRBi reports honoraria from Incyte, Bristol Myers Squibb, Sanofi, and ADC Therapeutics; consulting/advisory role for Novartis, Kite/Gilead, Bristol Myers Squibb, Sana Bio, and CRISPR Therapeutics; and speakers’ bureau participation for Incyte, Bristol Myers Squibb, Sanofi, and ADC Therapeutics. MST reports consulting/advisory role for Amgen, Celgene, Kite, Regeneron, and Roche and research funding from Amgen, Kite, MacroGenics, Regeneron, and Roche. DT reports consulting/advisory role for Bristol Myers Squibb, EUSA, Partner, and Takeda; and research funding from Bristol Myers Squibb. KMO reports consulting/advisory role for Beam Therapeutics. MLA reports consulting/advisory role for Kite and Syndax Pharmaceuticals, Inc. and research funding from Kite (institutional PI). YL reports consulting/advisory role for Kite/Gilead, Celgene/BMS, Juno/BMS, bluebird bio, Janssen, Legend Biotech, Gamida Cell, Novartis, Iovance, Takeda, Fosun Kite, and Pfizer and research funding from Kite/Gilead, Celgene/BMS, bluebird bio, Janssen, Legend Biotech, Merck, Takeda, and Boston Scientific. MRBa reports research funding from AbbVie, Ascentage, Kite, Kura, and Takeda. GJS reports honoraria and research funding from and speakers’ bureau participation for Kite. MS reports consulting/advisory role for Amgen, Celgene/BMS, Gilead Sciences, Janssen, and Novartis; speakers’ bureau participation for Celgene/BMS, Gilead Sciences, Janssen, and Novartis; research funding from Amgen, Gilead Sciences, Miltenyi Biotec, MorphoSys, Roche, and Seattle Genetics; and travel support from Takeda. MA reports stock or other ownership in CytoDyn; consulting/advisory role for Celgene; and speakers’ bureau participation for Celgene, Bristol Myers Squibb, AbbVie, and Kite. MCM reports consulting/advisory role for Gilead Sciences and Janssen-Cilag and speakers’ bureau participation for Janssen-Cilag and Medscape. WW reports consulting/advisory role for Genzyme and Sanofi and research funding from AbbVie, Acerta, Cyclacel, Genentech, Gilead Sciences, GSK, Janssen, Juno, Karyopharm, Loxo Oncology, miRagen, Novartis, Oncternal, Pharmacyclics, Sunesis, and Xencor. DJD reports consulting or advisory role for Agios, Amgen, Autolus, Blueprint Medicines, Forty Seven, Gilead Sciences, Incyte, Jazz, Novartis, Pfizer, Shire, and Takeda and research funding from AbbVie, Glycomimetics, Novartis, and Blueprint Medicines. PJS reports honoraria from and consulting or advisory role for MorphoSys and CRISPR Therapeutics and research funding from Amgen, Gamida Cell, Pfizer, Karyopharm, Gilead Sciences, Incyte, Seagen, and Cellectar. DJ reports research funding from Jazz Pharmaceuticals and Pfizer. DM has nothing to report. SA reports employment with and stock or other ownership in Kite. LZ reports employment with Kite and ownership of AbbVie RSU or stock in the past 2 years. reports employment with Kite; stock or other ownership in Gilead Sciences; and travel support from Kite and Gilead Sciences. RDK reports employment, stock, or other ownership in Kite. AG reports consulting/advisory role for Amgen, Atara, Bristol Myers Squibb, CRISPR Therapeutics, Kite, and Wugen Inc.; research funding from Amgen, Genentech, and Kite; and honoraria from Kite., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2023
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28. Once-Daily Foscarnet Is Effective for Human Herpesvirus 6 Reactivation after Hematopoietic Stem Cell Transplantation.
- Author
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Vittayawacharin P, E'Leimat G, Lee BJ, Griffin S, Doh J, Nam H, Blodget E, Jeyakumar D, Kongtim P, and Ciurea SO
- Subjects
- Adult, Humans, Young Adult, Middle Aged, Aged, Adolescent, Foscarnet therapeutic use, Transplantation, Homologous, DNA, Viral, Herpesvirus 6, Human physiology, Hematopoietic Stem Cell Transplantation adverse effects
- Abstract
Human herpesvirus 6 (HHV-6) reactivation is common after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is associated with higher mortality and increased transplantation-related complications. We hypothesized that preemptive treatment with a short course of foscarnet at a lower cutpoint of plasma HHV-6 viral load would be effective in treating early HHV-6 reactivation, preventing complications and precluding hospitalization of these patients. We reviewed outcomes of adult patients (age ≥18 years) who received preemptive treatment with once-daily foscarnet 60 to 90 mg/kg for 7 days for HHV-6 reactivation after allo-HSCT at our institution between May 2020 and November 2022. Plasma HHV-6 viral load was monitored by quantitative PCR twice monthly in the first 100 days post-transplantation and twice weekly after reactivation until resolution. Eleven patients with a median age of 46 years (range, 23 to 73 years) were included in the analysis. HSCT was performed with a haploidentical donor in 10 patients and with an HLA-matched related donor in 1 patient. The most common diagnosis was acute leukemia (9 patients). Myeloablative and reduced-intensity conditioning regimens were used in 4 and 7 patients, respectively. Ten of the 11 patients received post-transplantation cyclophosphamide-based graft-versus-host disease prophylaxis. The median follow-up was 440 days (range, 174 to 831 days), and the median time to HHV-6 reactivation was 22 days post-transplantation (range, 15 to 89 days). The median viral load at first reactivation was 3,100 copies/mL (range, 210 to 118,000 copies/mL), and the median peak viral load was 11,300 copies/mL (range, 600 to 983,000 copies/mL). All patients received a short course of foscarnet at either 90 mg/kg/day (n = 7) or 60 mg/kg/day (n = 4). In all patients, plasma HHV-6 DNA was undetectable at completion of 1 week of treatment. No HHV-6 encephalitis or pneumonitis occurred. All patients achieved neutrophil and platelet engraftment after a median of 16 days (range, 8 to 22 days) and 26 days (range, 14 to 168 days), respectively, with no secondary graft failure. No complications related to foscarnet administration were noted. One patient with very high HHV-6 viremia had recurrent reactivation and received a second course of foscarnet as an outpatient. A short course of once-daily foscarnet is effective in treating early HHV-6 reactivation post-transplantation and may reduce the incidence of HHV-6-related and treatment-related complications and preclude hospitalization in these patients., (Copyright © 2023 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)
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- 2023
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29. Timing of intrathecal chemotherapy and blinatumomab impacts neurotoxicity in acute lymphoblastic leukemia.
- Author
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Lee BJ, Griffin SP, Doh J, Kongtim P, Chan A, O'Brien S, Jeyakumar D, and Ciurea SO
- Subjects
- Humans, Precursor Cell Lymphoblastic Leukemia-Lymphoma drug therapy, Antineoplastic Agents adverse effects, Antibodies, Bispecific adverse effects, Precursor B-Cell Lymphoblastic Leukemia-Lymphoma drug therapy
- Published
- 2023
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30. Dasatinib/prednisone induction followed by blinatumomab/dasatinib in Ph+ acute lymphoblastic leukemia.
- Author
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Advani AS, Moseley A, O'Dwyer KM, Wood BL, Park J, Wieduwilt M, Jeyakumar D, Yaghmour G, Atallah EL, Gerds AT, O'Brien SM, Liesveld JL, Othus M, Litzow M, Stone RM, Sharon E, and Erba HP
- Subjects
- Humans, Aged, Aged, 80 and over, Dasatinib adverse effects, Prednisone therapeutic use, Treatment Outcome, Precursor Cell Lymphoblastic Leukemia-Lymphoma therapy
- Abstract
Novel treatment strategies are needed for the treatment of Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) in older patients. This trial evaluated the feasibility and outcomes with the anti-CD19 bispecific T-cell-engaging antibody, blinatumomab, in combination with dasatinib and steroids. Patients 65 years of age or older with Ph+ or Ph-like ALL (with dasatinib-sensitive fusions/mutations) were eligible and could be newly diagnosed or relapsed/refractory. Induction therapy consisted of dasatinib/prednisone. Patients not achieving response by day 56 proceeded to blinatumomab reinduction therapy. Patients achieving response with induction or reinduction therapy proceeded to blinatumomab/dasatinib postremission therapy for 3 cycles followed by dasatinib/prednisone maintenance. All patients received central nervous system prophylaxis with intrathecal methotrexate for a total of 8 doses. Response was assessed at days 28, 56, and 84 and at additional time points based on response parameters. Measurable residual disease was assessed centrally by 8-color flow cytometry at day 28. A total of 24 eligible patients with newly diagnosed Ph+ ALL were enrolled with a median age of 73 years (range, 65-87 years). This combination was safe and feasible. With a median of 2.7 years of follow-up, 3-year overall survival and disease-free survival were 87% (95% confidence interval [CI], 64-96) and 77% (95% CI, 54-90), respectively. Although longer follow-up is needed, these results are encouraging, and future trials are building on this backbone regimen. This trial was registered at www.clinicaltrials.gov as #NCT02143414., (Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
- Published
- 2023
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31. Two-year follow-up of KTE-X19 in patients with relapsed or refractory adult B-cell acute lymphoblastic leukemia in ZUMA-3 and its contextualization with SCHOLAR-3, an external historical control study.
- Author
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Shah BD, Ghobadi A, Oluwole OO, Logan AC, Boissel N, Cassaday RD, Leguay T, Bishop MR, Topp MS, Tzachanis D, O'Dwyer KM, Arellano ML, Lin Y, Baer MR, Schiller GJ, Park JH, Subklewe M, Abedi M, Minnema MC, Wierda WG, DeAngelo DJ, Stiff P, Jeyakumar D, Dong J, Adhikary S, Zhou L, Schuberth PC, Faghmous I, Masouleh BK, and Houot R
- Subjects
- Humans, Adult, Immunotherapy, Adoptive methods, Retrospective Studies, Historically Controlled Study, Recurrence, Antigens, CD19 therapeutic use, Receptors, Chimeric Antigen, Precursor Cell Lymphoblastic Leukemia-Lymphoma drug therapy
- Abstract
Background: Brexucabtagene autoleucel (KTE-X19) is an autologous anti-CD19 CAR T-cell therapy approved in the USA to treat adult patients with relapsed or refractory B-precursor acute lymphoblastic leukemia (R/R B-ALL) based on ZUMA-3 study results. We report updated ZUMA-3 outcomes with longer follow-up and an extended data set along with contextualization of outcomes to historical standard of care., Methods: Adults with R/R B-ALL received a single infusion of KTE-X19 (1 × 10
6 CAR T cells/kg). Long-term post hoc subgroup assessments of ZUMA-3 were conducted. Outcomes from matched patients between historical clinical trials and ZUMA-3 patients were assessed in the retrospective historical control study SCHOLAR-3., Results: After 26.8-months median follow-up, the overall complete remission (CR) rate (CR + CR with incomplete hematological recovery) among treated patients (N = 55) in phase 2 was 71% (56% CR rate); medians for duration of remission and overall survival (OS) were 14.6 and 25.4 months, respectively. Most patients responded to KTE-X19 regardless of age or baseline bone marrow blast percentage, but less so in patients with > 75% blasts. No new safety signals were observed. Similar outcomes were observed in a pooled analysis of phase 1 and 2 patients (N = 78). In SCHOLAR-3, the median OS for treated patients from ZUMA-3 (N = 49) and matched historical controls (N = 40) was 25.4 and 5.5 months, respectively., Conclusions: These data, representing the longest follow-up of CAR T-cell therapy in a multicenter study of adult R/R B-ALL, suggest that KTE-X19 provides a clinically meaningful survival benefit with manageable toxicity in this population., Trial Registration: NCT02614066., (© 2022. The Author(s).)- Published
- 2022
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32. CD19-directed immunotherapy use in KMT2A-rearranged acute leukemia: A case report and literature review of increased lymphoid to myeloid lineage switch.
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Lee BJ, Griffin SP, Doh J, Chan A, O'Brien S, Jeyakumar D, Ciurea SO, Becker PS, and Kongtim P
- Subjects
- Humans, Cell Lineage, Immunotherapy, Gene Rearrangement, Leukemia, Myeloid, Acute genetics, Leukemia, Myeloid, Acute therapy
- Published
- 2022
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33. Shape-tuned, surface-active and support-free silver oxygen reduction electrocatalyst enabled high performance fully non-PGM alkaline fuel cell.
- Author
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Anandha Ganesh P, Prakrthi AN, Selva Chandrasekaran S, and Jeyakumar D
- Abstract
Exploring non-platinum group metal (n-PGM) based efficient oxygen reduction reaction (ORR) electro-catalysts is highly important for realizing advancement in sustainable next generation-alkaline anion exchange membrane fuel cells (AAEMFCs). Herein, we demonstrate a new "hierarchical shape tuning approach" for the synthesis of controlled sized and shaped non-PGM based Ag ORR electro-catalysts with surface active nano-islands. Hierarchical shapes ranging from spherical (S-AgNs), worm-in-sphere, sphere-in-worm and vermiform (worm-like) Ag nanostructures (V-AgNs) were obtained by precisely varying the ratios of capping agent to dual reducing agents in water at ambient conditions. Compared to S-AgNs, V-AgNs revealed a higher mass normalized ORR Tafel activity (0.303 A mg
Ag -1 at 0.9 V), onset (1.06 V) and half wave (0.78 V) potentials and higher retention of limiting current density (>88%) after 5000 cycles in 0.5 M potassium hydroxide (KOH) solution attributable to their unique worm like morphology with surface active nano-islands and support free-nature enabled better catalyst utilization. In a fully "non-PGM AAEMFC" (n-PAAEMFC), V-AgNs exhibited the highest fuel cell activity of 115.6 mW cm-2 and stable short-term durability (∼240 h) compared to S-AgNs (41.3 mW cm-2 ) and previously reported fully n-PAAEMFCs indicating their potential use in next-generation alkaline fuel cells., Competing Interests: Authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)- Published
- 2021
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34. A Patient with Supraclavicular Lymphadenopathy and Anterior Mediastinal Mass Presenting as a Rare Case of Composite Lymphoma: A Case Report and Literature Review.
- Author
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Raufi A, Jerkins J, Lyou Y, and Jeyakumar D
- Abstract
Composite lymphoma (CL) is a rare disease with 2 distinct lymphomas concurrently arising in a single patient with an estimated incidence of 1-4.7% of newly diagnosed lymphomas per year. CL most commonly involves 2 B-cell non-Hodgkin lymphomas (NHL) or a B-cell NHL with a Hodgkin lymphoma. Our case is unique in that it was a bilineage CL with both a T-cell and B-cell NHL, which has only been reported in a few case reports. A 49-year-old woman presented with several months of progressive cough, weight loss, dyspnea, and supraclavicular lymphadenopathy. Computed tomographic imaging done upon admission to the hospital found that she had extensive anterior and middle mediastinal lymphadenopathy as well as bilateral supraclavicular lymphadenopathy. The patient underwent an excisional biopsy on the supraclavicular lymph node and was found to have a composite lymphoma involving both a T-cell and B-cell NHL. Her final pathological diagnosis was peripheral T-cell lymphoma and lymphoplasmacytic lymphoma. The patient was found to have stage IIIB disease. Her HIV, hepatitis panel, and tuberculosis tests were all negative. She then underwent chemotherapy with dose-adjusted EPOCH-R (etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab). The patient showed a complete response and was then referred to a bone marrow transplant center for an autologous hematopoietic stem cell transplant. CL is a rare disease composed of at least 2 distinct lymphomas concurrently arising in a single patient. Due to the complexity in having to treat multiple types of lymphoma simultaneously CL presents challenges with treatment and assessing prognosis.
- Published
- 2016
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35. An ab initio molecular orbital study of the reduction of carbonyls by alkylaluminum complexes.
- Author
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Bundens JW, Seida PR, Jeyakumar D, and Francl MM
- Subjects
- Energy Transfer, Indicators and Reagents, Mathematical Computing, Models, Chemical, Models, Molecular, Oxidation-Reduction, Oxides chemistry, Aluminum chemistry, Carbon chemistry, Organometallic Compounds chemistry
- Abstract
Semi-empirical and ab initio MO methods were used to explore mechanisms for the reduction of carbonyls by alkylaluminum reagents. Two distinct pathways have been observed experimentally, depending on the stoichiometric amounts of the reagents present. The corresponding intermediates and transition structures have been characterized. Alkylaluminum alkoxides are generally less reactive than the analogous alkylaluminum complexes. We suggest that the controlling factor here is not binding of the substrate, but the higher barrier to reaction of the alkoxide.
- Published
- 2005
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36. A sensitive, quantitative assay for human immunodeficiency virus type 1 integration.
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O'Doherty U, Swiggard WJ, Jeyakumar D, McGain D, and Malim MH
- Subjects
- CD4-Positive T-Lymphocytes cytology, Cell Line, Gene Products, gag genetics, Humans, Linear Models, Sensitivity and Specificity, DNA, Viral physiology, HIV-1 genetics, Proviruses genetics, Virus Integration physiology
- Abstract
Quantitative methods to measure human immunodeficiency virus type 1 (HIV-1) integration promise to be important tools in dissecting the mechanisms whereby latent reservoirs of provirus are established, most notably in the resting T cells of patients receiving antiretroviral therapy. Here we describe a fluorescence-monitored, nested PCR assay that is able to quantify the relatively rare integration events that occur within these cells. Following DNA extraction, a nonkinetic preamplification step is performed with primers that bind genomic Alu elements and HIV-1 gag sequences, under conditions where primers, deoxynucleoside triphosphates, and enzyme are not limiting. This is followed by a kinetic PCR that quantitates HIV-1 long terminal repeat sequences. A T-cell-based integration standard which reflects the randomness of HIV-1 integration is also described. The assay is 10 to 100 times more sensitive than previously reported quantitative Alu PCR-based integration assays. It is specific for integration events, since no proviruses are detected in cells infected either in the presence of an integrase inhibitor or with an integrase-deficient virus. This method promises to provide important new insights into the processes underlying the accumulation and persistence of latent HIV-1 reservoirs and may eventually be useful clinically in monitoring the eradication of latent virus by novel therapies.
- Published
- 2002
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37. Cyclic voltammetric measurements of growth of Aspergillus terreus.
- Author
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Subrahmanyam S, Kodandapani N, Shanmugam K, Moovarkumuthalvan K, Jeyakumar D, and Subramanian TV
- Subjects
- Biomass, Culture Media chemistry, Aspergillus growth & development, Electrochemistry methods
- Abstract
A detailed study using the cyclic voltammogram was done on the live cells of Aspergillus terreus. The peak current values were obtained for different days of growth and plotted against time. The response of cyclic voltammogram showed the phases of the growth of the fungus. The growth curve obtained matched well with the conventional methodology, which assesses the increase of dry weight of the organisms against time. The electrochemical method is more advantageous because it is easy to assess and consumes less time. Further the electrochemical method clearly shows the decline phase which is generally not very defined in the conventional method of assessment of the growth curve. It was confirmed by further experiments that the metabolites were responsible for the anodic peak and not the biomass. Further work is in progress in order to analyze the metabolite(s) that is/are responsible for the anodic peak.
- Published
- 2001
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