nayan.B. patel - Academia.edu (original) (raw)

Papers by nayan.B. patel

Summary Background Interest in improving the safety profile of healthcare continues and notable d... more Summary Background Interest in improving the safety profile of healthcare continues and notable developments have taken place in recent years in hospital settings, particularly in the developed world, to estimate the frequency of errors, understand causal factors, and to ...

Journal of Biological Chemistry

Following the portal vein injection of '261-insulin, radioactivity was taken up by rat liver and ... more Following the portal vein injection of '261-insulin, radioactivity was taken up by rat liver and concentrated in microsomes (30 to 50% of homogenate). Subfractionation of microsomes revealed that 30 to 60% of the label accumulated in Golgi elements. Uptake was inhibited by co-injected unlabeled insulin in a dose-dependent manner, by desalanine and desoctapeptide insulins, and by proinsulin in parallel with their capacities to inhibit insulin binding to its receptors. Structurally unrelated hormones did not inhibit uptake. Maximum labeling of the plasmalemma and Golgi heavy, intermediate, and light fractions occurred at 30 s, 2, 5, and 10 to 15 min, respectively. Redistribution of radiolabel during homogenization had no significant influence on the in vivo data. Electron microscope radioautography revealed grains intimately associated with Golgi elements with 50 to 60% of grains overlying the membranes of vesicles in the Golgi light and intermediate fractions. In Golgi heavy more grains (49%) were associated with small vesicles than flattened saccular elements (35%). 'ZsII-insulin eluted from the Golgi fractions had an integrity varying from 75 to 90% at 2 min to 44 to 55% at 20 min as judged by Sephadex chromatography and rebinding studies. These studies indicate that *251-insulin was internalized by a receptor-mediated process and concentrated in Golgi elements of the cell in a substantially intact form and, thus, raise the possibility of an intracellular site of action. In previous studies, using a direct binding approach and electron microscope radioautography, we have identified insulin binding sites in morphologically defined Golgi elements (I). The binding sites of the Golgi elements from both rat and mouse liver were found to be of high affinity and specificity for insulin and to have other properties similar to those of the plasmalemma (2, 3). The Golgi apparatus is involved in concentrating and modifying secretory material prior to exocytosis (4). On the basis of cytochemical evidence that 5"nucleotidase activity can be localized to Golgi membranes (5, 6) and that both insulin and lactogen receptors can be identified *This work was supported by Grants MT-4182 (to B.I.P.) and MA-5605 (to J. J. M. B.

ECS Meeting Abstracts

Determinar los factores de la dinámica familiar relacionados a la funcionalidad familiar en un gr... more Determinar los factores de la dinámica familiar relacionados a la funcionalidad familiar en un grupo de familias del primer nivel de atención. Material y Métodos: Se realizó un estudio descriptivo, retrospectivo y transversal, a través de estudios de diagnóstico de salud familiar y los instrumentos de evaluación del subsistema conyugal y FACES III, aplicados a familias adscritas a la Unidad de Medicina Familiar No 66 del IMSS de Xalapa, México, durante el periodo marzo 2003-diciembre 2004, el análisis comparativo de los resultados se realizó a través de χ 2. Resultados: Se incluyeron 103 diagnósticos de salud familiar, de acuerdo a la tipología familiar 82% fueron integradas, 82% nucleares, 51% tradicionales, 86% urbanas y 75% empleadas. Con respecto a la dinámica familiar el 65% de las familias presentó comunicación directa, el 64% límites claros y el 48% jerarquía recíproca con autoridad. De acuerdo con la evaluación del subsistema conyugal, encontramos 52% de parejas funcionales, 39% de parejas moderadamente disfuncionales y 9% de parejas severamente disfuncionales. Los resultados del FACES III, revelaron 43% de familias en rango medio, 41% de familias balanceadas y 16% de familias extremas. La comunicación directa predominó en las familias balanceadas, mientras que enmascarada en las de rango medio y la desplazada en las extremas (p= 0.0001). En cuanto a los límites éstos fueron claros en las familias balanceadas, difusos en las de rango medio y rígidos en las familias extremas (p = 0.00251). Conclusiones: La comunicación directa, y los límites claros predominaron en las familias funcionales y balanceadas.

Two pot experiments were performed in the greenhouse of the National Research Centre, Dokki, Giza... more Two pot experiments were performed in the greenhouse of the National Research Centre, Dokki, Giza, Egypt, during two successive summer seasons of 2014 and 2015 to study the Allelopathic potentiality of Eruca sativa (ESSP) and Raphanus sativus seed powder (RSSP) on the growth, yield of Helianthus annuus as well as associated narrow and broadleaved weeds Echinochloa crus-galli and Corchorus olitorius. Treatments were applied by incorporating seed powder of E. sativa (ESSP) and R. sativus (RSSP) to the soil at (0, 15, 30, 45 and 60g/kg soil). All ESSP as well as RSSP concentrations used minimized to great extent the dry weight of the two weeds at 60 days after sowing (DAS) and at the harvest. The highest reduction recorded with the highest concentration (60g/kg soil) of both material used. On the other hand, H. annuus growth and yield, yield components as well as oil content percentage were significantly increased with the most ESSP and RSSP concentrations used as compared to their corresponding mixed controls. The best results were recorded with ESSP treatment at 45g/kg soil and with RSSP at 30 g/kg soil concentration; these treatments achieved maximum increases over their corresponding control free from weed (Healthy). The allelopathic effect of ESSP and RSSP due to the presence of the allelochemicals: glucosinolates and phenolic compounds which play an important role in controlling the two annual narrow and broad-leaved weeds associating H. annuus and also increasing its yield.

The Journal of Nutrition Health and Aging

Objectives-To explore the association between body mass index and mortality in the elderly taking... more Objectives-To explore the association between body mass index and mortality in the elderly taking the diagnosis of dementia into account. Design-Cohort study. Setting-cohort study of aging in Medicare recipients in New York City. Participants-1,452 elderly individuals 65 years and older of both genders. Measurements-We used proportional hazards regression for longitudinal multivariate analyses relating body mass index (BMI) and weight change to all-cause mortality. Results-There were 479 deaths during 9,974 person-years of follow-up. There were 210 cases of prevalent dementia at baseline, and 209 cases of incident dementia during follow-up. Among 1,372 persons with BMI information, the lowest quartile of BMI was associated with a higher mortality risk compared to the second quartile (HR = 1.5; 95% CI: 1.1,2.0) after adjustment for age, gender, education, ethnic group, smoking, cancer, and dementia. When persons with dementia were excluded, both the lowest (HR = 1.9; 95% CI =1.3,2.6) and highest (HR = 1.6; 95% CI : 1.1,2.3) quartiles of BMI were related to higher mortality. Weight loss was related to a higher mortality risk (HR = 1.5; 95% CI: 1.2,1.9) but this association was attenuated when persons with short follow-up or persons with dementia were excluded. Conclusion-The presence of dementia does not explain the association between low BMI and higher mortality in the elderly. However, dementia may explain the association between weight loss and higher mortality.

Estuarine and Coastal Marine Science

Reproduction Nutrition Développement, 1980

IEEE Photonics Journal, 2011

We demonstrate monolithic integration of a 100-channel arrayed-waveguide grating (AWG) with 10-GH... more We demonstrate monolithic integration of a 100-channel arrayed-waveguide grating (AWG) with 10-GHz channel spacing and 100 optically controlled Michelsoninterferometer-based phase and amplitude modulators. The high-resolution AWG showed better than À15-dB crosstalk, and the modulator extinction ratio was better than 20 dB with either electrical or optical modulation control. The twin-integrated devices comprise a 50-mm diameter InP wafer with 1200 independent optoelectronic components.

Archiv der Pharmazie, 1964

Securing L2TP using IPsec Status of this Memo This document specifies an Internet standards track... more Securing L2TP using IPsec Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

International Journal of Oral and Maxillofacial Surgery, 2005

Bone SPECT is able to reduce the number of unnecessary mandibular resections by 59%. A negative b... more Bone SPECT is able to reduce the number of unnecessary mandibular resections by 59%. A negative bone SPECT rules out mandibular invasion. Important clinical implications of a negative bone SPECT are that further imaging is, then, unnecessary and the surgical procedure can be kept limited. Inclusion of SPECT bone scans in the preoperative work-up of patients with SCC, adjacent or fixed to the mandible, will lead to a considerable reduction in the number of unnecessary mandibular resections. This will reduce the morbidity and considerably improves the health related quality of life of these patients.

Leukemia, Jan 3, 2015

Mutations in isocitrate dehydrogenase 1/2 (IDH1/2(MT)) are drivers of a variety of myeloid neopla... more Mutations in isocitrate dehydrogenase 1/2 (IDH1/2(MT)) are drivers of a variety of myeloid neoplasms. As they yield the same oncometabolite, D-2-hydroxyglutarate, they are often treated as equivalent, and pooled. We studied the validity of this approach and found IDH1/2 mutations in 179 of 2119 myeloid neoplasms (8%). Cross-sectionally, the frequencies of these mutations increased from lower- to higher-risk disease, thus suggesting a role in clinical progression. Variant allelic frequencies indicated that IDH1(MT) and IDH2(MT) are ancestral in up to 14/74 (19%) vs 34/99 (34%; P=0.027) of cases, respectively, illustrating the pathogenic role of these lesions in myeloid neoplasms. IDH1/2(MT) was associated with poor overall survival, particularly in lower-risk myelodysplastic syndromes. Ancestral IDH1(MT) cases were associated with a worse prognosis than subclonal IDH1(MT) cases, whereas the position of IDH2(MT) within clonal hierarchy did not impact survival. This may relate to disti...

2007 4th IEEE International Conference on Group IV Photonics, 2007

The paper analyzes the influence of model parameters and uncertainties on assessment of financial... more The paper analyzes the influence of model parameters and uncertainties on assessment of financial losses due to voltage sags. Several parameters associated with the stochastic estimation of system sag performance are considered, namely the number of fault positions on lines, fault resistance, transformer neutral impedance, time-varying fault rate, and pre-fault voltage profiles. Additionally, the influence of location in the network

Proceedings of the International Conference and Workshop on Emerging Trends in Technology - ICWET '10, 2010

Page 49. International Conference on Signals, Systems & Automation-2009 Machine Visio... more Page 49. International Conference on Signals, Systems & Automation-2009 Machine Vision Based Liquid Level Inspection System using Laplacian of Gaussian Edge detection Technique Ishan Doshi, Galav Dani, Bhaumit Patel ...

where he received his Ph.D. He spent two years working with the COMPS group at the University of ... more where he received his Ph.D. He spent two years working with the COMPS group at the University of the Witwatersrand as a graduate student and post-doc. His interests include granular materials, identifying promising processes from an energy and emissions perspective, and sustainable energy production.

SAARC Journal of Tuberculosis, Lung Diseases and HIV/AIDS, 2013

Introduction: In India, tuberculosis is the most common opportunistic infection among HIV positiv... more Introduction: In India, tuberculosis is the most common opportunistic infection among HIV positive patients. This study estimates the prevalence of tuberculosis amongst HIV patients in Ahmadabad, Gujarat. Methodology: The present study was conducted at Integrated Counseling and Testing Center for HIV at Sola civil hospital, a public sector tertiary care hospital in Ahmadabad for a twenty month period from January, 2009 to August, 2010. All the patients visiting the center during the study period were screened for HIV. All the patients who were diagnosed HIV positive were subjected for active search of tuberculosis; clinically, radiological as well as by histopathology and laboratory tests. Results: Total 6846 patients were screened for HIV, out of which 167(2.44%) patients were tested HIV positive. Out of 167 HIV positive patients, 22 (13.17%) were diagnosed as cases of tuberculosis. Out of these 22 patients, 18(81.82%) had pulmonary tuberculosis while 4(18.18%) were extra-pulmonary...

Advanced Energy Materials, 2014

ABSTRACT The challenges for rechargeable lithium-oxygen batteries of low practical capacity and p... more ABSTRACT The challenges for rechargeable lithium-oxygen batteries of low practical capacity and poor round-trip efficiency urgently demand effective cathode materials to overcome the limitations. However, the synergy between the multiple active materials was not well understood at large. Herein, we describe findings of the synergistic effect between electrospun zinc oxide (ZnO) nanofibers and graphene nanoribbons (GNRs) unzipped from carbon nanotubes (CNTs) as cathode materials in rechargeable lithium-oxygen batteries. Furthermore, the overpotentials and discharge capacities were tuned by the surface defect states of ZnO nanofibers and Pt nanocrytals in GNRs. It was observed that the optimized zinc oxide nanofibers hybridized with GNRs achieved a high reversible capacity of 6,300 mAh/gcarbon and enhanced stable cyclability under specific 50% of full discharge capacities. The focus of this report demonstrates the ZnO nanofibers with high degree of defects and hydrophilicity of the surface could be a promising cathode component for rechargeable lithium-oxygen batteries and the optimum synergy between ZnO nanofibers and GNRs could balance the discharge capacity and cycle life.

Summary Background Interest in improving the safety profile of healthcare continues and notable d... more Summary Background Interest in improving the safety profile of healthcare continues and notable developments have taken place in recent years in hospital settings, particularly in the developed world, to estimate the frequency of errors, understand causal factors, and to ...

Journal of Biological Chemistry

Following the portal vein injection of '261-insulin, radioactivity was taken up by rat liver and ... more Following the portal vein injection of '261-insulin, radioactivity was taken up by rat liver and concentrated in microsomes (30 to 50% of homogenate). Subfractionation of microsomes revealed that 30 to 60% of the label accumulated in Golgi elements. Uptake was inhibited by co-injected unlabeled insulin in a dose-dependent manner, by desalanine and desoctapeptide insulins, and by proinsulin in parallel with their capacities to inhibit insulin binding to its receptors. Structurally unrelated hormones did not inhibit uptake. Maximum labeling of the plasmalemma and Golgi heavy, intermediate, and light fractions occurred at 30 s, 2, 5, and 10 to 15 min, respectively. Redistribution of radiolabel during homogenization had no significant influence on the in vivo data. Electron microscope radioautography revealed grains intimately associated with Golgi elements with 50 to 60% of grains overlying the membranes of vesicles in the Golgi light and intermediate fractions. In Golgi heavy more grains (49%) were associated with small vesicles than flattened saccular elements (35%). 'ZsII-insulin eluted from the Golgi fractions had an integrity varying from 75 to 90% at 2 min to 44 to 55% at 20 min as judged by Sephadex chromatography and rebinding studies. These studies indicate that *251-insulin was internalized by a receptor-mediated process and concentrated in Golgi elements of the cell in a substantially intact form and, thus, raise the possibility of an intracellular site of action. In previous studies, using a direct binding approach and electron microscope radioautography, we have identified insulin binding sites in morphologically defined Golgi elements (I). The binding sites of the Golgi elements from both rat and mouse liver were found to be of high affinity and specificity for insulin and to have other properties similar to those of the plasmalemma (2, 3). The Golgi apparatus is involved in concentrating and modifying secretory material prior to exocytosis (4). On the basis of cytochemical evidence that 5"nucleotidase activity can be localized to Golgi membranes (5, 6) and that both insulin and lactogen receptors can be identified *This work was supported by Grants MT-4182 (to B.I.P.) and MA-5605 (to J. J. M. B.

ECS Meeting Abstracts

Determinar los factores de la dinámica familiar relacionados a la funcionalidad familiar en un gr... more Determinar los factores de la dinámica familiar relacionados a la funcionalidad familiar en un grupo de familias del primer nivel de atención. Material y Métodos: Se realizó un estudio descriptivo, retrospectivo y transversal, a través de estudios de diagnóstico de salud familiar y los instrumentos de evaluación del subsistema conyugal y FACES III, aplicados a familias adscritas a la Unidad de Medicina Familiar No 66 del IMSS de Xalapa, México, durante el periodo marzo 2003-diciembre 2004, el análisis comparativo de los resultados se realizó a través de χ 2. Resultados: Se incluyeron 103 diagnósticos de salud familiar, de acuerdo a la tipología familiar 82% fueron integradas, 82% nucleares, 51% tradicionales, 86% urbanas y 75% empleadas. Con respecto a la dinámica familiar el 65% de las familias presentó comunicación directa, el 64% límites claros y el 48% jerarquía recíproca con autoridad. De acuerdo con la evaluación del subsistema conyugal, encontramos 52% de parejas funcionales, 39% de parejas moderadamente disfuncionales y 9% de parejas severamente disfuncionales. Los resultados del FACES III, revelaron 43% de familias en rango medio, 41% de familias balanceadas y 16% de familias extremas. La comunicación directa predominó en las familias balanceadas, mientras que enmascarada en las de rango medio y la desplazada en las extremas (p= 0.0001). En cuanto a los límites éstos fueron claros en las familias balanceadas, difusos en las de rango medio y rígidos en las familias extremas (p = 0.00251). Conclusiones: La comunicación directa, y los límites claros predominaron en las familias funcionales y balanceadas.

Two pot experiments were performed in the greenhouse of the National Research Centre, Dokki, Giza... more Two pot experiments were performed in the greenhouse of the National Research Centre, Dokki, Giza, Egypt, during two successive summer seasons of 2014 and 2015 to study the Allelopathic potentiality of Eruca sativa (ESSP) and Raphanus sativus seed powder (RSSP) on the growth, yield of Helianthus annuus as well as associated narrow and broadleaved weeds Echinochloa crus-galli and Corchorus olitorius. Treatments were applied by incorporating seed powder of E. sativa (ESSP) and R. sativus (RSSP) to the soil at (0, 15, 30, 45 and 60g/kg soil). All ESSP as well as RSSP concentrations used minimized to great extent the dry weight of the two weeds at 60 days after sowing (DAS) and at the harvest. The highest reduction recorded with the highest concentration (60g/kg soil) of both material used. On the other hand, H. annuus growth and yield, yield components as well as oil content percentage were significantly increased with the most ESSP and RSSP concentrations used as compared to their corresponding mixed controls. The best results were recorded with ESSP treatment at 45g/kg soil and with RSSP at 30 g/kg soil concentration; these treatments achieved maximum increases over their corresponding control free from weed (Healthy). The allelopathic effect of ESSP and RSSP due to the presence of the allelochemicals: glucosinolates and phenolic compounds which play an important role in controlling the two annual narrow and broad-leaved weeds associating H. annuus and also increasing its yield.

The Journal of Nutrition Health and Aging

Objectives-To explore the association between body mass index and mortality in the elderly taking... more Objectives-To explore the association between body mass index and mortality in the elderly taking the diagnosis of dementia into account. Design-Cohort study. Setting-cohort study of aging in Medicare recipients in New York City. Participants-1,452 elderly individuals 65 years and older of both genders. Measurements-We used proportional hazards regression for longitudinal multivariate analyses relating body mass index (BMI) and weight change to all-cause mortality. Results-There were 479 deaths during 9,974 person-years of follow-up. There were 210 cases of prevalent dementia at baseline, and 209 cases of incident dementia during follow-up. Among 1,372 persons with BMI information, the lowest quartile of BMI was associated with a higher mortality risk compared to the second quartile (HR = 1.5; 95% CI: 1.1,2.0) after adjustment for age, gender, education, ethnic group, smoking, cancer, and dementia. When persons with dementia were excluded, both the lowest (HR = 1.9; 95% CI =1.3,2.6) and highest (HR = 1.6; 95% CI : 1.1,2.3) quartiles of BMI were related to higher mortality. Weight loss was related to a higher mortality risk (HR = 1.5; 95% CI: 1.2,1.9) but this association was attenuated when persons with short follow-up or persons with dementia were excluded. Conclusion-The presence of dementia does not explain the association between low BMI and higher mortality in the elderly. However, dementia may explain the association between weight loss and higher mortality.

Estuarine and Coastal Marine Science

Reproduction Nutrition Développement, 1980

IEEE Photonics Journal, 2011

We demonstrate monolithic integration of a 100-channel arrayed-waveguide grating (AWG) with 10-GH... more We demonstrate monolithic integration of a 100-channel arrayed-waveguide grating (AWG) with 10-GHz channel spacing and 100 optically controlled Michelsoninterferometer-based phase and amplitude modulators. The high-resolution AWG showed better than À15-dB crosstalk, and the modulator extinction ratio was better than 20 dB with either electrical or optical modulation control. The twin-integrated devices comprise a 50-mm diameter InP wafer with 1200 independent optoelectronic components.

Archiv der Pharmazie, 1964

Securing L2TP using IPsec Status of this Memo This document specifies an Internet standards track... more Securing L2TP using IPsec Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

International Journal of Oral and Maxillofacial Surgery, 2005

Bone SPECT is able to reduce the number of unnecessary mandibular resections by 59%. A negative b... more Bone SPECT is able to reduce the number of unnecessary mandibular resections by 59%. A negative bone SPECT rules out mandibular invasion. Important clinical implications of a negative bone SPECT are that further imaging is, then, unnecessary and the surgical procedure can be kept limited. Inclusion of SPECT bone scans in the preoperative work-up of patients with SCC, adjacent or fixed to the mandible, will lead to a considerable reduction in the number of unnecessary mandibular resections. This will reduce the morbidity and considerably improves the health related quality of life of these patients.

Leukemia, Jan 3, 2015

Mutations in isocitrate dehydrogenase 1/2 (IDH1/2(MT)) are drivers of a variety of myeloid neopla... more Mutations in isocitrate dehydrogenase 1/2 (IDH1/2(MT)) are drivers of a variety of myeloid neoplasms. As they yield the same oncometabolite, D-2-hydroxyglutarate, they are often treated as equivalent, and pooled. We studied the validity of this approach and found IDH1/2 mutations in 179 of 2119 myeloid neoplasms (8%). Cross-sectionally, the frequencies of these mutations increased from lower- to higher-risk disease, thus suggesting a role in clinical progression. Variant allelic frequencies indicated that IDH1(MT) and IDH2(MT) are ancestral in up to 14/74 (19%) vs 34/99 (34%; P=0.027) of cases, respectively, illustrating the pathogenic role of these lesions in myeloid neoplasms. IDH1/2(MT) was associated with poor overall survival, particularly in lower-risk myelodysplastic syndromes. Ancestral IDH1(MT) cases were associated with a worse prognosis than subclonal IDH1(MT) cases, whereas the position of IDH2(MT) within clonal hierarchy did not impact survival. This may relate to disti...

2007 4th IEEE International Conference on Group IV Photonics, 2007

The paper analyzes the influence of model parameters and uncertainties on assessment of financial... more The paper analyzes the influence of model parameters and uncertainties on assessment of financial losses due to voltage sags. Several parameters associated with the stochastic estimation of system sag performance are considered, namely the number of fault positions on lines, fault resistance, transformer neutral impedance, time-varying fault rate, and pre-fault voltage profiles. Additionally, the influence of location in the network

Proceedings of the International Conference and Workshop on Emerging Trends in Technology - ICWET '10, 2010

Page 49. International Conference on Signals, Systems & Automation-2009 Machine Visio... more Page 49. International Conference on Signals, Systems & Automation-2009 Machine Vision Based Liquid Level Inspection System using Laplacian of Gaussian Edge detection Technique Ishan Doshi, Galav Dani, Bhaumit Patel ...

where he received his Ph.D. He spent two years working with the COMPS group at the University of ... more where he received his Ph.D. He spent two years working with the COMPS group at the University of the Witwatersrand as a graduate student and post-doc. His interests include granular materials, identifying promising processes from an energy and emissions perspective, and sustainable energy production.

SAARC Journal of Tuberculosis, Lung Diseases and HIV/AIDS, 2013

Introduction: In India, tuberculosis is the most common opportunistic infection among HIV positiv... more Introduction: In India, tuberculosis is the most common opportunistic infection among HIV positive patients. This study estimates the prevalence of tuberculosis amongst HIV patients in Ahmadabad, Gujarat. Methodology: The present study was conducted at Integrated Counseling and Testing Center for HIV at Sola civil hospital, a public sector tertiary care hospital in Ahmadabad for a twenty month period from January, 2009 to August, 2010. All the patients visiting the center during the study period were screened for HIV. All the patients who were diagnosed HIV positive were subjected for active search of tuberculosis; clinically, radiological as well as by histopathology and laboratory tests. Results: Total 6846 patients were screened for HIV, out of which 167(2.44%) patients were tested HIV positive. Out of 167 HIV positive patients, 22 (13.17%) were diagnosed as cases of tuberculosis. Out of these 22 patients, 18(81.82%) had pulmonary tuberculosis while 4(18.18%) were extra-pulmonary...

Advanced Energy Materials, 2014

ABSTRACT The challenges for rechargeable lithium-oxygen batteries of low practical capacity and p... more ABSTRACT The challenges for rechargeable lithium-oxygen batteries of low practical capacity and poor round-trip efficiency urgently demand effective cathode materials to overcome the limitations. However, the synergy between the multiple active materials was not well understood at large. Herein, we describe findings of the synergistic effect between electrospun zinc oxide (ZnO) nanofibers and graphene nanoribbons (GNRs) unzipped from carbon nanotubes (CNTs) as cathode materials in rechargeable lithium-oxygen batteries. Furthermore, the overpotentials and discharge capacities were tuned by the surface defect states of ZnO nanofibers and Pt nanocrytals in GNRs. It was observed that the optimized zinc oxide nanofibers hybridized with GNRs achieved a high reversible capacity of 6,300 mAh/gcarbon and enhanced stable cyclability under specific 50% of full discharge capacities. The focus of this report demonstrates the ZnO nanofibers with high degree of defects and hydrophilicity of the surface could be a promising cathode component for rechargeable lithium-oxygen batteries and the optimum synergy between ZnO nanofibers and GNRs could balance the discharge capacity and cycle life.