Maéli M. F. Civa, Dirceu Aparecido Gonçalves de Souza, Renata Silva, D. D. S. A. Maciel, R. L. Tranquilin, S. Diniz, Cristina E. Okuyama, M. L. Santos, R. M. Pereira
The coordination of metal ions with flavonoids is applied to improve its pharmacological properties. To evaluate the role of ions on diosmin new complexes with Fe(II), Cu(II) and Co(II) ions were synthetized and characterized by UV, FT-IR and XRD techniques and surface morphology by SEM. The biological activity of coordination complexes in vitro, the antioxidant (ABTS), antibacterial (disc diffusion and MIC) and antitumoral activities (MTT) were analyzed. Diosmin when reacting with Fe(II) at 50oC loses the sugar molecule becoming diosmetin (D) coordinated at 1D:1Fe ratio. In presence of Cu(II) and Co(II) at the same conditions besides losing the sugar, diosmin loses the methyl group at C4’ and H at C3’, producing a new ligand and complexes at 1D:2Cu or Co ratio, to produce DCu and DCo, respectively. The coordination of Cu and Fe improve the antioxidant activity of diosmin. DCo was the only presented antibacterial activity. Additionally, a specific antitumor effect of diosmin and metal complexes upon human leukemia cells was demonstrated, suggesting an immune regulatory action. The anti-melanoma activity of DCo is 10 times better than diosmin. Metal coordination could be used to improve drug activity and to give direction to a new possibility of clinical use for diosmin.
{"title":"Metal Complexes Derived of Diosmin with Biological Activities in vitro","authors":"Maéli M. F. Civa, Dirceu Aparecido Gonçalves de Souza, Renata Silva, D. D. S. A. Maciel, R. L. Tranquilin, S. Diniz, Cristina E. Okuyama, M. L. Santos, R. M. Pereira","doi":"10.5539/jmsr.v9n1p10","DOIUrl":"https://doi.org/10.5539/jmsr.v9n1p10","url":null,"abstract":"The coordination of metal ions with flavonoids is applied to improve its pharmacological properties. To evaluate the role of ions on diosmin new complexes with Fe(II), Cu(II) and Co(II) ions were synthetized and characterized by UV, FT-IR and XRD techniques and surface morphology by SEM. The biological activity of coordination complexes in vitro, the antioxidant (ABTS), antibacterial (disc diffusion and MIC) and antitumoral activities (MTT) were analyzed. Diosmin when reacting with Fe(II) at 50oC loses the sugar molecule becoming diosmetin (D) coordinated at 1D:1Fe ratio. In presence of Cu(II) and Co(II) at the same conditions besides losing the sugar, diosmin loses the methyl group at C4’ and H at C3’, producing a new ligand and complexes at 1D:2Cu or Co ratio, to produce DCu and DCo, respectively. The coordination of Cu and Fe improve the antioxidant activity of diosmin. DCo was the only presented antibacterial activity. Additionally, a specific antitumor effect of diosmin and metal complexes upon human leukemia cells was demonstrated, suggesting an immune regulatory action. The anti-melanoma activity of DCo is 10 times better than diosmin. Metal coordination could be used to improve drug activity and to give direction to a new possibility of clinical use for diosmin.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"83 1","pages":"10"},"PeriodicalIF":0.0,"publicationDate":"2019-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76100561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Polypyrrole (PPy) layers were deposited on lead metallic surface using hydrogen peroxide or benzoyl peroxide as oxidizing agent associated with different types of dopants: phosphoric acid, stearic acid and dodecylbenzene sulfonic acid. Lead alloy was chosen because of its importance in energy industrial application and also because its primary source of extraction is running out, there is an increasingly urgent need to extend its life cycle. For the in situ chemical deposition of PPy, it was considered the combination of only one oxidizing agent and one dopant, being the experiment performed with the combination of these reagents. The morphology and corrosion protection effectiveness of the PPy layer was studied by Scanning Electron Microscope (SEM), Open Circuit Potential (OCP) and Potentiodynamic Polarization. The experimental results demonstrate that PPy layer was effectively formed as a coating layer and Hydrogen Peroxide performed better and consistent protection efficiency when compared to Benzoyl Peroxide.
{"title":"The Influence of Oxidizing Agent in the Chemical Deposition of Polypyrrole on Lead Alloy Surface","authors":"Inês Pinheiro, L. Cho","doi":"10.5539/jmsr.v9n1p1","DOIUrl":"https://doi.org/10.5539/jmsr.v9n1p1","url":null,"abstract":"Polypyrrole (PPy) layers were deposited on lead metallic surface using hydrogen peroxide or benzoyl peroxide as oxidizing agent associated with different types of dopants: phosphoric acid, stearic acid and dodecylbenzene sulfonic acid. Lead alloy was chosen because of its importance in energy industrial application and also because its primary source of extraction is running out, there is an increasingly urgent need to extend its life cycle. For the in situ chemical deposition of PPy, it was considered the combination of only one oxidizing agent and one dopant, being the experiment performed with the combination of these reagents. The morphology and corrosion protection effectiveness of the PPy layer was studied by Scanning Electron Microscope (SEM), Open Circuit Potential (OCP) and Potentiodynamic Polarization. The experimental results demonstrate that PPy layer was effectively formed as a coating layer and Hydrogen Peroxide performed better and consistent protection efficiency when compared to Benzoyl Peroxide.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"148 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2019-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83806705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Nguyen, Naoto Miyakita, O. Kiyotaka, Okubo Kazuya
It is well known that thermoplastic composite is vulnerable to impact fracture. Submicron glass fiber (sGF) was used to modify the matrix of chopped tape carbon fiber reinforced polypropylene composite. The impact resistance improved 20% and 7.4% coressponding to the dimeter sGF of 0.28 and 0.69 µm used in modified-composite. To shed light upon the mechanism of this improvement, the internal damage statement of post-impact specimens was observed by the CT scanner. The results pointed out that the increase of the impact resistance was due to the enlargement of delamination area under impact load. The micro droplet test and end notch flexure test suggest that the decrease of Mode II fracture toughness in modified-composite comes from narrowing the difference between the interfacial shear strength (IFSS) and the bending strength of matrix thanks to significant improving of IFSS with the addition of sGF while the flexural strength remains the unchanged. Consequently, the failure mode changed from debonding fiber/matrix in unmodified composite into brittle matrix failure in modified composite, resulting in the decrease of the Mode II interlaminar fracture toughness and the enlargement of delamination area. The stress transfer test also indicates that the modified composites is prone to the brittle matrix failure.
{"title":"Impact Improvement of Tape Carbon Fiber Composite Modified by Submicron Glass Fiber","authors":"N. Nguyen, Naoto Miyakita, O. Kiyotaka, Okubo Kazuya","doi":"10.5539/jmsr.v8n4p21","DOIUrl":"https://doi.org/10.5539/jmsr.v8n4p21","url":null,"abstract":"It is well known that thermoplastic composite is vulnerable to impact fracture. Submicron glass fiber (sGF) was used to modify the matrix of chopped tape carbon fiber reinforced polypropylene composite. The impact resistance improved 20% and 7.4% coressponding to the dimeter sGF of 0.28 and 0.69 µm used in modified-composite. To shed light upon the mechanism of this improvement, the internal damage statement of post-impact specimens was observed by the CT scanner. The results pointed out that the increase of the impact resistance was due to the enlargement of delamination area under impact load. The micro droplet test and end notch flexure test suggest that the decrease of Mode II fracture toughness in modified-composite comes from narrowing the difference between the interfacial shear strength (IFSS) and the bending strength of matrix thanks to significant improving of IFSS with the addition of sGF while the flexural strength remains the unchanged. Consequently, the failure mode changed from debonding fiber/matrix in unmodified composite into brittle matrix failure in modified composite, resulting in the decrease of the Mode II interlaminar fracture toughness and the enlargement of delamination area. The stress transfer test also indicates that the modified composites is prone to the brittle matrix failure.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76151656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is about a decade since graphene became a material for serious research by researchers in condensed matter of various nationalities making significant progress. This paper on graphene growth and characterization: advances, present challenges and prospects is therefore timely. Basic topics such as graphene and graphene technology, history and trend of graphene as well as graphene growth and synthesis have been discussed. Also presented are fundamental and mechanical properties, structural and morphological property characterization using different techniques. Graphene in biomedical and radio frequency applications, transparent electronics, integrated circuits, quantum dots, frequency multiplier, optical modulator and piezoelectricity and as a battery super capacitor are some applications and uses of graphene that have been considered. The lowering of the growth temperature of graphene has been found to be beneficial for the compartibility with other materials and processes and could also decrease the impact of cooling-induced wrinkling on the morphology of graphene; the growth on dielectric substrates; being able to resolve many problems associated with metallic growth substrates; better control of both the formation and the extension of additional layers on the graphene through substrate engineering that will result in approaches of graphene that is envisaged are some of the advances and future prospects. Also, the proposed tunable bandgap for graphene which is essential for microelectronics which contributes one of the present challenges is likely to be achieved in the very near future. Although theoretical and computational analyses have proved to have solved the zero bandgap problem of graphene, more convincing approaches that will solve the problem and give way for the fabrication of high performance graphene device are being awaited.
{"title":"Graphene Growth and Characterization: Advances, Present Challenges and Prospects","authors":"J. U. Arikpo, M. Onuu","doi":"10.5539/jmsr.v8n4p37","DOIUrl":"https://doi.org/10.5539/jmsr.v8n4p37","url":null,"abstract":"It is about a decade since graphene became a material for serious research by researchers in condensed matter of various nationalities making significant progress. This paper on graphene growth and characterization: advances, present challenges and prospects is therefore timely. Basic topics such as graphene and graphene technology, history and trend of graphene as well as graphene growth and synthesis have been discussed. Also presented are fundamental and mechanical properties, structural and morphological property characterization using different techniques. Graphene in biomedical and radio frequency applications, transparent electronics, integrated circuits, quantum dots, frequency multiplier, optical modulator and piezoelectricity and as a battery super capacitor are some applications and uses of graphene that have been considered. The lowering of the growth temperature of graphene has been found to be beneficial for the compartibility with other materials and processes and could also decrease the impact of cooling-induced wrinkling on the morphology of graphene; the growth on dielectric substrates; being able to resolve many problems associated with metallic growth substrates; better control of both the formation and the extension of additional layers on the graphene through substrate engineering that will result in approaches of graphene that is envisaged are some of the advances and future prospects. Also, the proposed tunable bandgap for graphene which is essential for microelectronics which contributes one of the present challenges is likely to be achieved in the very near future. Although theoretical and computational analyses have proved to have solved the zero bandgap problem of graphene, more convincing approaches that will solve the problem and give way for the fabrication of high performance graphene device are being awaited.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85926231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Noritomi, Ryotaro Kai, N. Endo, Satoru Kato, K. Uchiyama
We have found that the heat stress tolerance of hen egg white lysozyme (HEWL) is markedly enhanced by the adsorption of HEWL on bamboo charcoal powder (BCP), which is a kind of biochar. HEWL was firmly adsorbed on BCP even at high temperatures. The secondary structure of HEWL was altered to some extent by the adsorption of HEWL on BCP. The remaining activity of BCP-adsorbed HEWL exhibited more than 20% after the incubation for 30 min at 900C although that of free one was hardly observed. Moreover, the half-life of BCP-adsorbed HEWL was 13 min at 900C while that of free one was 4 min.
{"title":"Thermal Stabilization of HEWL by Adsorption on Biochar","authors":"H. Noritomi, Ryotaro Kai, N. Endo, Satoru Kato, K. Uchiyama","doi":"10.5539/JMSR.V8N4P30","DOIUrl":"https://doi.org/10.5539/JMSR.V8N4P30","url":null,"abstract":"We have found that the heat stress tolerance of hen egg white lysozyme (HEWL) is markedly enhanced by the adsorption of HEWL on bamboo charcoal powder (BCP), which is a kind of biochar. HEWL was firmly adsorbed on BCP even at high temperatures. The secondary structure of HEWL was altered to some extent by the adsorption of HEWL on BCP. The remaining activity of BCP-adsorbed HEWL exhibited more than 20% after the incubation for 30 min at 900C although that of free one was hardly observed. Moreover, the half-life of BCP-adsorbed HEWL was 13 min at 900C while that of free one was 4 min.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77218843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The versatility of the DNA origami approach of organizing nanoparticles at the nanometer scale, together with thiol chemistry have been used. These approaches were used to design DNA origami structures and to functionalize them with gold nanoparticles after designing attachment sites on the DNA origami structures. In all two structures were designed – a cross-like structure and a nanotube but only the nanotube structure was used to form the gold nanoparticle helices. Finally, use was made of the specific affinity interaction between biotin and streptavidin to connect the DNA origami templated AuNP helices to the cross-like structure. Agarose gel electrophoresis, UV-vis spectroscopy and TEM were used to characterize the structure.
{"title":"Connecting DNA Origami Structures into a Designed and Functionalized Network","authors":"G. Amoako","doi":"10.5539/jmsr.v8n4p14","DOIUrl":"https://doi.org/10.5539/jmsr.v8n4p14","url":null,"abstract":"The versatility of the DNA origami approach of organizing nanoparticles at the nanometer scale, together with thiol chemistry have been used. These approaches were used to design DNA origami structures and to functionalize them with gold nanoparticles after designing attachment sites on the DNA origami structures. In all two structures were designed – a cross-like structure and a nanotube but only the nanotube structure was used to form the gold nanoparticle helices. Finally, use was made of the specific affinity interaction between biotin and streptavidin to connect the DNA origami templated AuNP helices to the cross-like structure. Agarose gel electrophoresis, UV-vis spectroscopy and TEM were used to characterize the structure.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81360187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bárbara Ferreira de Oliveira, M. P. Oliveira, L. Terrones, M. G. Azevedo, L. Godefroid
This paper presents a study on the microstructure and mechanical properties of a microalloyed HSLA steel solidified by continuous casting process and annealed at 1100 °C for 1 hour. The techniques of confocal microscopy, scanning electron microscopy and hardness, tensile and Charpy mechanical tests were used. The results of this research showed that the microstructure of the sample in the as-received condition was mainly composed of acicular ferrite and aggregates of ferrite and carbides. Non-metallic inclusion characterization of as-cast steel showed that calcium content was not enough to modify the morphology of some aluminates. After thermal treatment, the initial microstructure was transformed into polygonal ferrite and pearlite. In both conditions, different types of precipitates were found, which were classified according to their distribution in the microstructure. The steel with solidification structure showed a higher tensile strength, but its application would be unlikely in components that require good impact strength.
{"title":"Microstructure and mechanical properties of as-cast and annealed high strength low alloy steel","authors":"Bárbara Ferreira de Oliveira, M. P. Oliveira, L. Terrones, M. G. Azevedo, L. Godefroid","doi":"10.5539/jmsr.v8n4p1","DOIUrl":"https://doi.org/10.5539/jmsr.v8n4p1","url":null,"abstract":"This paper presents a study on the microstructure and mechanical properties of a microalloyed HSLA steel solidified by continuous casting process and annealed at 1100 °C for 1 hour. The techniques of confocal microscopy, scanning electron microscopy and hardness, tensile and Charpy mechanical tests were used. The results of this research showed that the microstructure of the sample in the as-received condition was mainly composed of acicular ferrite and aggregates of ferrite and carbides. Non-metallic inclusion characterization of as-cast steel showed that calcium content was not enough to modify the morphology of some aluminates. After thermal treatment, the initial microstructure was transformed into polygonal ferrite and pearlite. In both conditions, different types of precipitates were found, which were classified according to their distribution in the microstructure. The steel with solidification structure showed a higher tensile strength, but its application would be unlikely in components that require good impact strength.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"78 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79064342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Popoola O. Abduljelili, G. I. Olatona, Muhammed Abdullahi
The temperature of clay box used in the ballistic testing of body amour drops sharply upon removal from the oven. This implies that the clay has to be reinserted into the oven for another heating, which slows down the ballistic testing procedure. This paper attempts to solve the problem by studying the effect of addition of different percentages of rubber cuttings, saw dust and berley reeds additives on the cooling rate of clay used in clay box construction. The cooling rate is a measure of the ballistic performance of the clay box. The properties of the clay box such as the density, thermal conductivity and specific heat capacity are factored into the lump system analysis model. Minimum cooling rate of about 2.04×10-03 and 1.89×10-03oC/s were obtained when 0% and 10% rubber cuttings were used as dopands respectively. Rubber cuttings also proved to be the best additives that can be used to enhance the ballistic performance of clay box used in the ballistic testing of body armour.
{"title":"Lump System Analysis Modelling for Enhanced Ballistic Performance of Clay Box Doped with Different Types of Additives","authors":"Popoola O. Abduljelili, G. I. Olatona, Muhammed Abdullahi","doi":"10.5539/JMSR.V8N3P23","DOIUrl":"https://doi.org/10.5539/JMSR.V8N3P23","url":null,"abstract":"The temperature of clay box used in the ballistic testing of body amour drops sharply upon removal from the oven. This implies that the clay has to be reinserted into the oven for another heating, which slows down the ballistic testing procedure. This paper attempts to solve the problem by studying the effect of addition of different percentages of rubber cuttings, saw dust and berley reeds additives on the cooling rate of clay used in clay box construction. The cooling rate is a measure of the ballistic performance of the clay box. The properties of the clay box such as the density, thermal conductivity and specific heat capacity are factored into the lump system analysis model. Minimum cooling rate of about 2.04×10-03 and 1.89×10-03oC/s were obtained when 0% and 10% rubber cuttings were used as dopands respectively. Rubber cuttings also proved to be the best additives that can be used to enhance the ballistic performance of clay box used in the ballistic testing of body armour.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80116931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Brostow, H. E. H. Lobland, H. Hong, Sven Lohse, Allison T. Osmanson
We have quantitatively defined flexibility of polymers. Flexibility Y is not an inverse of the brittleness B, rather, the two equations are compared. The expression for flexibility includes the specific volume and the summation of the strengths of chemical bonds-a concept introduced by Linus Pauling. The flexibility is plotted as a function of dynamic friction, resulting in a representative single curve for polymers.
{"title":"Flexibility of Polymers Defined and Related to Dynamic Friction","authors":"W. Brostow, H. E. H. Lobland, H. Hong, Sven Lohse, Allison T. Osmanson","doi":"10.5539/JMSR.V8N3P31","DOIUrl":"https://doi.org/10.5539/JMSR.V8N3P31","url":null,"abstract":"We have quantitatively defined flexibility of polymers. Flexibility Y is not an inverse of the brittleness B, rather, the two equations are compared. The expression for flexibility includes the specific volume and the summation of the strengths of chemical bonds-a concept introduced by Linus Pauling. The flexibility is plotted as a function of dynamic friction, resulting in a representative single curve for polymers.","PeriodicalId":16111,"journal":{"name":"Journal of Materials Science Research","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73424971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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