Nanoscale Advances最新文献

{"title":"Diffusiophoresis in porous media saturated with a mixture of electrolytes.","authors":"Siddharth Sambamoorthy, Henry C W Chu","doi":"10.1039/d4na00984c","DOIUrl":"10.1039/d4na00984c","url":null,"abstract":"<p><p>Current theories of diffusiophoresis in porous media are limited to a porous medium saturated with a valence symmetric electrolyte. A predictive model for diffusiophoresis in porous media saturated with a valence asymmetric electrolyte, or a general mixture of valence symmetric and asymmetric electrolytes, is lacking. To close this knowledge gap, in this work we develop a mathematical model, based upon the regular perturbation method and numerical integration, to compute the diffusiophoretic mobility of a colloid in porous media saturated with a general mixture of electrolytes. We model the electrokinetics using the Poisson-Nernst-Planck equations and the fluid transport in porous media using the Brinkman equation with an electric body force. We report three novel key findings. First, we demonstrate that, in the same electrolyte concentration gradient, lowering the permeability of the porous medium can significantly weaken the colloid diffusiophoretic motion. Second, we show that, surprisingly, by using a valence asymmetric electrolyte the colloid diffusiophoretic motion in a denser porous medium can be stronger than that in a less dense porous medium saturated with a symmetric electrolyte. Third, we demonstrate that varying the composition of an electrolyte mixture does not only change the strength of the colloid diffusiophoretic motion drastically, but also qualitatively its direction. The model developed from this work can be used to understand and predict natural phenomena such as intracellular transport, as well as design technological applications such as enhanced oil recovery, nanoparticle drug delivery, and colloidal species separation.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11836625/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143468717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Mo-doped carbon dot nanozyme for enhanced phototherapy <i>in vitro</i>.","authors":"Wenlong Wang, Xuan Sheng, Yihan Wang, Mingjun Yu, Yue Shen, Youfu Xia, Tiao Li, Shuai Cao, Mengjuan Zhang, Wenjian Wang, Yongjian Yang","doi":"10.1039/d5na00028a","DOIUrl":"10.1039/d5na00028a","url":null,"abstract":"<p><p>Cancer is a leading cause of death globally, and traditional treatment methods often come with non-negligible toxic side effects in its treatment, threatening patients' quality of life. Thus, developing novel, efficient, low-toxicity cancer treatment strategies is crucial. Nanozymes, as a class of powerful nanomaterials, can subtly mimic the catalytic activity of natural enzymes, making them a formidable alternative. Hypoxic molybdenum oxide (MoO_3-<i>x</i> ), as a typical nanozyme material, possesses unique physical and chemical properties, showing great potential in fields such as cancer treatment. In this study, a simple and rapid one-pot hydrothermal synthesis method was ingeniously employed, innovatively combining molybdenum, which has high biosafety, with safflower, which exhibits anticancer pharmacological activity, to successfully prepare hypoxic molybdenum oxide (MoO_3-<i>x</i> )-doped safflower carbon dots (H-Mo-CDs). H-Mo-CDs exhibit exceptional catalase (CAT)-like, peroxidase (POD)-like, and superoxide dismutase (SOD)-like catalytic activities and superior photothermal conversion efficiency and photostability. <i>In vitro</i> cellular experiments have verified their multiple therapeutic potentials in photothermal therapy (PTT), chemodynamic therapy (CDT), and photodynamic therapy (PDT), providing novel ideas and means for precise cancer treatment. This study not only paves an efficient and feasible path for the development of Mo-based nanomaterials as \"smart\" nanozymes but also injects new vitality and possibilities into the types and applications of nanozymes in cancer treatment.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11851171/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143516212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of precursor coverage in the synthesis and substrate transfer of graphene nanoribbons.","authors":"Rimah Darawish, Oliver Braun, Klaus Müllen, Michel Calame, Pascal Ruffieux, Roman Fasel, Gabriela Borin Barin","doi":"10.1039/d5na00017c","DOIUrl":"10.1039/d5na00017c","url":null,"abstract":"<p><p>Graphene nanoribbons (GNRs) with atomically precise widths and edge topologies have well-defined band gaps that depend on ribbon dimensions, making them ideal for room-temperature switching applications like field-effect transistors (FETs). For effective device integration, it is crucial to optimize growth conditions to maximize GNR length and, consequently, device yield. Equally important is establishing device integration and monitoring strategies that maintain GNR quality during the transition from growth to device fabrication. Here, we investigate the growth and alignment of 9-atom-wide armchair graphene nanoribbons (9-AGNRs) on a vicinal gold substrate, Au(788), with varying molecular precursor doses (PD) and, therefore, different resulting GNR coverages. Our investigation reveals that GNR growth location on Au(788) substrate is coverage-dependent. Scanning tunneling microscopy shows a strong correlation between GNR length evolution and both PD and GNR growth location. Employing Raman spectroscopy, samples with eight different PDs were analyzed. GNR alignment improves with length, achieving near-perfect alignment with an average length of ∼40 nm for GNRs growing solely at the Au(788) step edges. To fully exploit GNR properties in device architectures, GNRs need to be transferred from their metallic growth substrate to semiconducting or insulating substrates. Upon transfer, samples with higher PD present systematically better alignment preservation and less surface disorder, attributed to reduced GNR mobility during the transfer process. Importantly, PD also affects the substrate transfer success rate, with higher success rates observed for samples with higher GNR coverages (77%) compared to lower GNR coverages (53%). Our findings characterize the important relationship between precursor dose, GNR length, alignment quality, and surface disorder during GNR growth and upon substrate transfer, offering crucial insights for the further development of GNR-based nanoelectronic devices.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11812448/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143408721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structurally engineered heat loss suppression in nanogap-aligned nanowires for power efficient heating.","authors":"Min-Seung Jo, Beom-Jun Kim, Myung-Kun Chung, Se-Yoon Jung, Min-Ho Seo, Jae-Young Yoo, Jae-Soon Yang, Sung-Ho Kim, Jun-Bo Yoon","doi":"10.1039/d4na00894d","DOIUrl":"10.1039/d4na00894d","url":null,"abstract":"<p><p>Thermal management at the nanoscale offers potential advancements in power-efficient geometrical design; however, both conduction- and convection-based structural optimization have yet to be fully investigated due to dimensional limitations. In this study, we analytically designed a structured configuration within a regime comparable to the mean free path of heat-transferring carriers. The optimally designed nanowire configuration, featuring aligned nanowires with narrow gaps (∼22 nm), was designed based on the analytic calculation. A tailored nanofabrication technique enabled a reliable geometrical parametric study, experimentally validating the proposed theoretical design. Finally, by engineering both conduction heat loss and air molecular interactions in convective heat loss at the nanoscale, we suggest an optimized heater for atmospheric conditions based on scaling factor-induced thermophysical properties, surpassing the efficiency of traditional film-based heaters.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11827604/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143433494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Induction of enhanced stem-directed neutralizing antibodies by HA2-16 ferritin nanoparticles with H3 influenza virus boost.","authors":"Qingyu Wang, Jiaojiao Nie, Zejinxuan Liu, Yaotian Chang, Yangang Wei, Xin Yao, Lulu Sun, Xiaoxi Liu, Qicheng Liu, Xinyu Liang, Xinran Zhang, Yong Zhang, Weiheng Su, Qi Zhao, Yaming Shan, Yingwu Wang, Xianbin Cheng, Yuhua Shi","doi":"10.1039/d4na00964a","DOIUrl":"10.1039/d4na00964a","url":null,"abstract":"<p><p>Current seasonal influenza vaccines offer limited protection against influenza viruses due to genetic drift. The urgent need for a universal influenza vaccine to combat highly mutated strains is evident. This study utilized the conserved HA2 subunit of hemagglutinin (HA) and a short linear epitope of HA2 (HA2-16) from the H3 influenza virus to conjugate with ferritin, resulting in the construction of recombinant immunogens termed HA2-F and HA2-16-F, respectively. <i>In vitro</i> characterization confirmed the self-assembly of prokaryotically expressed HA2-F and HA2-16-F into nanoparticles (NPs). To simulate natural virus infection in the vaccinated population, intranasal infection with the whole H3N2 virus was administered as a final boost. Enhanced binding activity to A/Hong Kong/4801/2014 (H3N2) and A/17/California/2009/38 (H1N1) virus was detected in the HA2-16 group induced by the A/Wisconsin/67/2005 (H3N2) virus boost (Titer >10⁴). Furthermore, higher titers of neutralizing antibodies were elicited by HA2-16-F NP (ID₅₀: 50.4-631.0) compared to those by HA2-F NP (ID₅₀: 20.3-178.2). These results demonstrated that the H3N2 virus boost focused the antibody response on the HA2-16 epitope. Additionally, our immunization strategy was found to reduce serum ferritin reactive antibodies. In summary, HA2-16 not only holds promise as a vaccine candidate but also exhibits significant potential for influenza vaccine production, particularly in enhancing the levels of induced stem-directed antibodies. This study contributes to the development of recombinant immunogens for improved influenza vaccine efficacy.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11833233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An octahedral metal oxide nanoparticle-based dual-signal sensing platform for simultaneous detection of histidine and lysine in human blood plasma and urine.","authors":"Robina Akhtar, Asim Yaqub, Zia Ul Haq Khan, Ali Turab Jafry, Huma Ajab","doi":"10.1039/d4na00932k","DOIUrl":"10.1039/d4na00932k","url":null,"abstract":"<p><p>Histidine and lysine serve as essential amino acids in physiological processes and biomarkers for specific diseases, requiring precise detection methods in a variety of samples. This study presents an affordable single colorimetric probe that employs nickel oxide nanoparticles (NiONPs) as an artificial enzyme to detect histidine and lysine, improving conventional analytical limitations. The characterization of NiONPs was executed using SEM-EDX, FE-SEM, FTIR and XRD. The NiONPs demonstrated peroxidase-like catalytic activity on the conversion of TMB to oxidized TMB (oxTMB) in the presence of H₂O₂, utilizing optimization parameters like pH value (3), TMB concentration (10 mM), H₂O₂ concentration (60 mM), and incubation time (18 min). The study revealed that Ni and O atoms are present on the surface of NiONPs, allowing for specific interactions with essential amino acids and temporarily hindering the catalytic activity of oxidized TMB. The method exhibited a low limit of detection (LOD) of 0.07 μM (10-100 μM) for histidine and 1.1 μM (15-150 μM) for lysine with good stability. The proposed strategy was validated with urine and plasma samples, yielding favorable recoveries of 93.6-98.2% in urine and 90.5-96.0% in plasma for histidine and 91.2-94.8% in urine and 88.4-93.3% in plasma for lysine, supporting its selectivity, feasibility, and reliability for practical applications. In the future, this methodology will facilitate the integration of histidine and lysine detection into microfluidic systems using NiONPs as a colorimetric probe.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808276/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Light driven water oxidation on silica supported NiO-TiO₂ heteronanocrystals yields hydrogen peroxide.","authors":"Nurul Muttakin, Shelton J P Varapragasam, Rashed Mia, Mahfuz A Swadhen, Michael Odlyzko, James D Hoefelmeyer","doi":"10.1039/d4na00906a","DOIUrl":"10.1039/d4na00906a","url":null,"abstract":"<p><p>Decomposition of nickel nitrate hexahydrate in the presence of rod-shape anatase TiO₂ nanocrystals led to the formation of NiO-TiO₂ heteronanocrystals confirmed with powder X-ray diffraction and electron microscopy. The heteronanocrystals were supported on amorphous fumed silica to provide a heterogeneous photocatalyst material SiO₂/NiO-TiO₂. The aqueous suspension of the catalyst, under argon atmosphere, irradiated with a Xe arc lamp led to the formation of H₂O₂ with trace gaseous product formation. We observed an initial rate of formation of H₂O₂ of 1.8 μmol g^-1 min^-1 that decays toward a steady-state concentration of 52 μM. Addition of AgNO₃ to the aqueous suspension gave fast reduction of silver ion, and higher initial rates of formation and steady state concentrations of H₂O₂. We report the concentration dependence of water oxidation <i>versus</i> [AgNO₃] with the fastest initial rate of formation of H₂O₂ as 9.1 μmol g^-1 min^-1 and a steady-state concentration of 174 μM.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808566/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reversible doping and fine-tuning of the Dirac point position in the topological crystalline insulator Pb_1-<i>x</i> Sn _<i>x</i> Se <i>via</i> sputtering and annealing process.","authors":"Artem Odobesko, Johannes Jung, Andrzej Szczerbakow, Jędrzej Korczak, Tomasz Story, Matthias Bode","doi":"10.1039/d4na00821a","DOIUrl":"10.1039/d4na00821a","url":null,"abstract":"<p><p>In this study, we utilize scanning tunneling microscopy and spectroscopy to detail a sputter- and annealing methodology for preparing atomically clean Pb_1-<i>x</i> Sn _<i>x</i> Se(001) surfaces. We examine the impact these processes have on the surface quality, the composition, and the electronic properties. Our findings demonstrate that annealing temperatures between 250 °C and 280 °C produce smooth surfaces while maintaining the topological properties of Pb_1-<i>x</i> Sn _<i>x</i> Se. Fine control of the annealing temperature also allows for a reversible tuning of the doping level, enabling a positive or negative shift of the Dirac point energy with respect to the Fermi level. Our results highlight the effectiveness of these cleaning methods and demonstrate their potential for future research and applications in topological crystalline insulator materials.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808273/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143399564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High performance supercapacitors driven by the synergy of a redox-active electrolyte and core-nanoshell zeolitic imidazolate frameworks.","authors":"Mansi, Vishal Shrivastav, Prashant Dubey, Aristides Bakandritsos, Shashank Sundriyal, Umesh K Tiwari, Akash Deep","doi":"10.1039/d4na00805g","DOIUrl":"10.1039/d4na00805g","url":null,"abstract":"<p><p>The selection of appropriate electrolytes plays a crucial role in improving the electrochemical performance of the supercapacitor electrode. The electrolyte helps to select an appropriate potential window of the device, which is directly related to its energy density. Also, the selection of an appropriate electrode material targets the specific capacitance. Therefore, in this work, we targeted an electrode material based on a ZIF-8@ZIF-67 (Z867) core-nanoshell structure and tested its performance in redox active electrolyte (RAE), <i>i.e.</i>, 0.2 M K₃[Fe(CN)₆] in 1 M Na₂SO₄. The synergy between the core-nanoshell electrode having ZIF-8 as a core and ZIF-67 as a nanoshell along with RAE further complements the redox active sites, resulting in the improved charge transport. Therefore, when the Z867 core-nanoshell electrode is tested in a three-electrode system, it outperforms pristine ZIF-8 and ZIF-67 electrode materials. The working electrode modified with the Z867 core-nanoshell showed a maximum specific capacitance of 496.4 F g^-1 at 4.5 A g^-1 current density with the RAE, which is much higher than that of the aqueous electrolyte. A Z867-modified working electrode was assembled as the positive and negative electrode in a symmetrical cell configuration to create a redox supercapacitor device for practical application. The constructed device displayed maximal energy and power densities of 49.6 W h kg^-1 and 3.2 kW kg^-1 respectively, along with a capacitance retention of 92% after 10 000 charge-discharge cycles. Hence, these studies confirm that using RAE can improve the electrochemical performance of electrodes to a greater extent than that of aqueous electrolyte-based supercapacitors.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11844434/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143483663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct chemical lithography writing on 2D materials by electron beam induced chemical reactions.","authors":"Iryna Danylo, Lukáš Koláčný, Kristína Kissíková, Tomáš Hartman, Martina Pitínová, Jiří Šturala, Zdeněk Sofer, Martin Veselý","doi":"10.1039/d5na00036j","DOIUrl":"10.1039/d5na00036j","url":null,"abstract":"<p><p>Due to their high surface-to-volume ratio and native band gaps, two-dimensional (2D) materials are widely used as supports for metal nanoparticle (NP) catalysts. Various synthesis methods exist to prepare such materials, but controlling the amount, size, and distribution of the deposited NPs remains a challenge. Here, we investigate the use of electron beam lithography (EBL) for this purpose. A dual-beam focused ion beam-scanning electron microscope (FIB-SEM) was used to direct the deposition of platinum NPs (Pt NPs) onto 2D graphene oxide, functionalized with epoxy and hydroxyl (HUGO) or carboxyl (TOGO) groups, and black phosphorus (BP) sheets. According to NP size, the deposition was conducted for various exposure times and several types of particle distribution. EDS confirmed the required chemical composition of all of the prepared materials. SEM showed the amount and distribution of the supported NPs, and TEM confirmed their size. Raman spectroscopy revealed a strong bonding between the NPs and the support sheets according to the type of 2D support. These results suggest that EBL is a promising method for the target-controlled deposition of metal NPs of targeted amount, size, and spatial distribution onto 2D materials, which enables evaluating the specific influence of the NP-support interaction on enhanced catalytic activity.</p>","PeriodicalId":18806,"journal":{"name":"Nanoscale Advances","volume":" ","pages":""},"PeriodicalIF":4.6,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11833312/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}