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- 摘要
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<p>Biodistribution and sensitive tracking of immune cells with plasmonic gold nanostars</p>
摘要： Aim: To quantitatively and sensitively investigate the biodistribution of immune cells after systemic administration. Methods: Immune cells were loaded with plasmonic gold nanostars (GNS) tracking probes. Inductively coupled plasma mass spectrometry (ICP-MS) was used for quantitative gold mass measurement and two-photon photoluminescence (TPL) was used for high-resolution sensitive optical imaging. Results: GNS nanoparticles were loaded successfully into immune cells without negative effect on cellular vitality. Liver and spleen were identified to be the major organs for macrophage cells uptake after systematic administration. A small amount of macrophage cells were detected in the tumor site in our murine lymphoma animal model. Conclusion: GNS has great potential as a biocompatible marker for quantitative tracking and high-resolution imaging of immune cells at the cellular level.
关键词： biodistribution,immune cells,GNS,ICP-MS,two-photon microscopy
更新于2025-11-19 16:56:42
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Synthesis and optical band gap determination of CuO nanoparticles from salen-based infinite coordination polymer nanospheres
摘要： A symmetric bi-carboxylic acid functionalized salen-type ligand was used as organic linker to prepare a Cu-based infinite coordination polymer. The analytical data demonstrated that the proposed structure contains one bi-carboxylic acid salen type ligand and two copper cations in each monomeric unit. One of the Cu2+ cations is coordinated by N2O2 site of salen ligand and the other one acts as node to connect metal-organic linkers to each other. The reasonable formation mechanism for coordination polymer formation proposed which shows the formation of nanoparticles from intertwined oligomer chains. The prepared coordination polymer was used as a good precursor to synthesis copper oxide nanoparticles with larger band gap relative to bulk CuO.
关键词： CuO,salen-type ligand,ICP,band gap,nanoparticles
更新于2025-09-23 15:23:52
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[IEEE 2018 25th IEEE International Conference on Image Processing (ICIP) - Athens, Greece (2018.10.7-2018.10.10)] 2018 25th IEEE International Conference on Image Processing (ICIP) - 3D Human Pose Estimation Using Stochastic Optimization in Real Time
摘要： Random Tree Walkers (RTW) are a well-established method for human pose estimation, because they deliver state-of-the-art performance at low computational cost. As the forests capabilities for generalization are limited, the algorithm fails to estimate unlearned poses very quickly. The proposed method pushes this limitation by combining the RTW with optimization methods such as iterative closest point (ICP) and a stochastic search. The RTW is being used to initialize various hypotheses in different ways which are then passed to the optimization stage of the proposed method. The quality of each hypothesis is assessed by a cost function measuring the discrepancy between the data and a human body model generated for each hypothesis. Experimental results show a greater number of correctly estimated poses over a single RTW result.
关键词： Random Tree Walk,Genetic Algorithm,ICP,Multihypotheses,Human Pose Estimation
更新于2025-09-23 15:22:29
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[IEEE 2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP) - Stuttgart, Germany (2018.11.20-2018.11.22)] 2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP) - 3D Point Cloud Coarse Registration based on Convex Hull Refined by ICP and NDT
摘要： Non-rigid registration is a crucial step for many applications such as motion tracking, model retrieval, and object recognition. The accuracy of these applications is highly dependent on the initial position used in registration step. In this paper we propose a novel Convex Hull Aided Coarse Registration refined by two algorithms applied on projected points.Firstly,the proposed approach uses a statistical method to find the best plane that represents each point cloud. Secondly, all the points of each cloud are projected onto the corresponding planes. Then, two convex hulls are extracted from the two projected point sets and then matched optimally. Next, the non-rigid transformation from the reference to the model is robustly estimated through minimizing the distance between the matched point's pairs of the two convex hulls.Finally, this transformation estimation is refined by two methods. The first one is the refinement of coarse registration by Iterative Closest Point (ICP). The second one consists of the refinement of coarse registration by the Normal Distribution Transform (NDT). An experimental study ,carried out on several clouds, shows that the refinement of coarse registration with ICP gives, in the most cases, a better result than refinement with NDT.
关键词： Iterative Closest Point (ICP),Convex Hull,Normal Distribution Transform (NDT),Non rigid registration,3D point cloud,Principal Component Analysis (PCA)
更新于2025-09-23 15:22:29
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[ACM Press the 2018 2nd International Conference - Barcelona, Spain (2018.08.03-2018.08.05)] Proceedings of the 2018 2nd International Conference on Cloud and Big Data Computing - ICCBDC'18 - Optical Flow Based Pose Estimation
摘要： In this paper, we present a new variant of ICP (iterative closest point) algorithm based on optical flow for finding better 3D point correspondence and computing six-degrees of freedom (6-DOF) pose of the rigid objects. Our approach integrates optical flow algorithm to ICP method, and proposed method gets advantage of higher resolution of the RGB sensor and depth information of the depth sensor. Fusing color and depth sensors improves pose estimation results. We set ground truth with Vicon motion tracker system. And, our approach is tested on a rigid object and compared to ICP method. Results have shown that optical flow and ICP method computes better rigid object pose estimation and lower error against ICP based pose estimation with only depth positions.
关键词： image projection,Iterative Closest Point (ICP),optical flow,Pose estimation
更新于2025-09-23 15:21:21
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Zircon fissiona??track and Ua??Pb double dating using femtosecond laser ablationa??inductively coupled plasmaa??mass spectrometry: A technical note
摘要： We present a new LA–ICP–MS system for zircon fission-track (FT) and U–Pb double dating, whereby a femtosecond laser combined with galvanometric optics simultaneously ablates multiple spots to measure average surface U contents. The U contents of zircon measured by LA–ICP–MS and standardized with the NIST SRM610 glass are comparable to those measured by the induced fission track method, and have smaller analytical errors. LA–ICP–MS FT dating of seven zircon samples including three IUGS age standards is as accurate as the external detector method, but can give a higher-precision age depending on the counting statistics of the U content measurement. Double dating of the IUGS age standards gives FT and U–Pb ages that are in agreement. A chip of the Nancy 91500 zircon has a homogeneous U content of 84 ppm, suggesting the possibility of using this zircon as a matrix-matched U standard for FT dating. When using the Nancy 91500 zircon as a U standard, a zeta calibration value of 42–43 yr cm?2 for LA–ICP–MS FT dating is obtained. While this value is strictly only valid for the particular session, it can serve as a reference for other studies.
关键词： dating,femtosecond laser,U–Pb,fission track,zircon,LA–ICP–MS
更新于2025-09-23 15:21:01
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Detection of Nutrition and Toxic Elements in Pakistani Pepper Powders Using Laser Induced Breakdown Spectroscopy
摘要： In the current paper, we applied laser induced breakdown spectroscopy (LIBS) to determine the elemental distribution of nutritional and trace heavy metals in pepper powders available in Pakistan using standard calibration curve laser induced breakdown spectroscopy (CC-LIBS) technique. The samples were found to contained elements like K, Ca, Mg, Na, Fe, Zn, Al, Pb, Cu, and Cr. Additionally, we also identified the atmospheric H-alpha line of hydrogen in the spectra which was used to estimate the electron number density. To achieve a highly sensitive LIBS system to determine nutritional and trace amounts of toxic metals in pepper powders and to achieve the best limit of detection, the LIBS system was optimized by studying the dependency of LIBS signal intensity on laser irradiance, variation in spacing between the focusing lens and target as well on the gate width. To justify the results of LIBS study, we also determined the concentration of alike (duplicate) peppers by digesting samples in appropriate solvents using a standard method like inductively coupled plasma-optical emission spectrometry (ICP-OES). The minimum detection limit was recognized for trace heavy metals from calibration curves. The results of LIBS displayed noteworthy conformity with those acquired from the ICP-OES analysis. Results of both the techniques clearly revealed that K was the most abundant element in all the peppers followed by Ca, Mg, Na, Fe, Al, Pb, Zn, Cu, and Cr. The relative accuracy of our LIBS system for different species as compared with ICP technique was in the range of 0.08–0.3 at 2.5 % error confidence. Conclusively, the present work demonstrated the suitability of LIBS technique due to its rapid, non destructive and eco-friendly approach for food security.
关键词： ICP-OES,detection of heavy metals,peppers analysis,laser induced breakdown spectroscopy,plasma parameters,Health impacts of toxic metals,laser applications
更新于2025-09-23 15:21:01
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Effects of the inductively coupled Ar plasma etching on the performance of (111) face CdZnTe detector
摘要： The effect of inductively coupled Ar plasma etching (ICP-Ar) instead of traditional Br–MeOH etching on the performance of CdZnTe detectors was studied. The optimal ICP etching parameters were determined by experiments. The XPS results indicated that the surface composition of CdZnTe etched by ICP-Ar had no obvious TeOx peak and was closer to stoichiometric ratio than that etched by Br–MeOH. The leakage current of ICP-Ar etched CdZnTe surface was significantly reduced, and the detection performance with the energy resolution was improved by 12%, as compared to Br–MeOH etched sample. Moreover, ICP-Ar etching abandoned the drawbacks of Br–MeOH by producing corrosive gases, making it safer and more environmentally friendly. Therefore, inductively coupled Ar plasma etching is expected to replace Br–MeOH etching and become an effective method for CdZnTe surface treatment.
关键词： Surface treatment,CdZnTe,ICP plasma
更新于2025-09-23 15:21:01
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Analysis of Yttria-Stabilized Zirconia by Inductively Coupled Plasma Atomic Emission Spectrometry
摘要： A method for determination of aluminum, hafnium, iron, yttrium, calcium, magnesium, and titanium by inductively coupled plasma atomic emission spectrometry (ICP-AES) is described. Conditions for the decomposition of two modifications of the analyzed material—unburnt and subjected to stabilizing firing—have been studied. It has been found that the unburnt zirconia dissolves in sulfuric acid, and the burnt sample can be converted to solution only by fusing with potassium pyrosulfate or potassium bifluoride. However, the application of these reagents leads to high values of the control experiment correction for trace impurities (at the level of tenths and hundredths of a percent). In this connection, we have studied the possibility of acid dissolution of the burnt sample under microwave decomposition, varying the qualitative and quantitative composition of the acid mixture, reaction temperature, and time to reach and maintain the required temperature. It has been found that the decomposition in the mixture of hydrofluoric and sulfuric acids (2 : 1) in the microwave system with stepwise heating of the reaction mixture ensures quantitative dissolution of the burnt sample and sufficiently low values of the control experiment correction for trace impurities. The analytical lines have been chosen taking into account their relative intensity, possible spectral overlaps, and the matrix effect in the analysis of model solutions containing 1.3 mg/cm3 Zr, 0.2 mg/cm3 Y, and from 0.2 to 20 mg/cm3 impurities. As a result, the following analytical lines have been chosen: Al II 167.079 nm and Al I 308.215 nm, Ca II 184.006 nm and 393.366 nm, Fe II 238.204 nm, Mg II 279.553 nm, Ti II 334.941 nm, Y II 371.030 nm, and Hf II 232.247 nm. The developed method for the analysis of yttria-stabilized zirconia by ICP-AES allows simultaneously determining aluminum, iron, magnesium, and titanium in the range of 0.01–1.0%; calcium, 0.02–1.0%; hafnium, 0.1–5.0%; and yttrium, 2.0–15% with a relative standard deviation of 6–30 rel % (for Al, Fe, Mg, Ti, and Ca), 2–7 rel % (Hg), and 2–4 rel % (Y). The correctness of the method is confirmed by the standard addition technique.
关键词： zirconium dioxide stabilized by yttrium dioxide,inductively coupled plasma atomic emission spectroscopy (ICP-AES),microwave sample preparation
更新于2025-09-23 15:21:01
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Spatially-resolved uranium isotopic analysis of contaminated scrap metal using laser ablation multi-collector ICP-MS
摘要： Laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) was applied to the detailed investigation of the uranium (U) isotopic composition (234U, 235U, 236U, and 238U) of five contaminated scrap metal samples found within the European Union. Pressed pellets of the two certified U isotopic reference materials CRM U-020 and CRM U-030 were included in the measurement protocol for mass bias correction, calculation of the ion counter gains and for quality assurance. Since the investigated samples had low U content (0.15–14.3 wt%) compared to typically analysed pure U compounds (>60 wt%), the applied experimental parameters had to be adjusted. Spatially-resolved U isotopic information was obtained by line scan analysis of each sample. While other analytical techniques used typically in nuclear forensic investigations, such as g-spectrometry and thermal ionisation mass spectrometry (TIMS) yielded average U isotopic compositions of the entire sample, LA-MC-ICP-MS provided substantial added value, highlighting the inhomogeneous distribution of U isotopes within various scrap metal samples. Analysis of individual particles via secondary ion mass spectrometry (SIMS) confirmed the large range of 235U enrichment levels in heterogeneous scrap metal samples. Four out of five scrap metal samples contained 236U ((cid:1)0.05–(cid:1)0.11 wt%), indicating the presence of reprocessed U. Taken together, LA-MC-ICP-MS analysis provided fast and accurate spatially-resolved U isotopic information without consuming or altering the scrap metal samples, a key feature for nuclear forensics investigations.
关键词： nuclear forensics,Laser ablation,multi-collector ICP-MS,uranium isotopic analysis,scrap metal
更新于2025-09-23 15:21:01