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1.
Plant Physiol ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005784

RESUMO

Chloroplasts divide by binary fission, which is driven by a ring-like multiprotein complex spanning the inner and outer envelope membranes at the division site. The cytosolic DYNAMIN-RELATED PROTEIN 5B (DRP5B/ARC5) is a mechanochemical GTPase involved in binary fission of the chloroplast membrane in Arabidopsis (Arabidopsis thaliana), but the dynamics of its interactions with the chloroplast membranes and their regulation by guanine nucleotides and protein effectors remain poorly characterized. Using an Arabidopsis phot2 mutant with defects in chloroplast photorelocation movement, we determined that the ring structures of DRP5B at the chloroplast division site underwent subunit exchange with a cytosolic DRP5B pool. Mutant DRP5B proteins with impaired GTPase activity retained the ability to self-assemble at the constriction sites of chloroplasts, but did not rescue the chloroplast division defects in the Arabidopsis drp5B mutant. Our in vivo kinetic measurements of the DRP5B mutant T82D suggested that turnover of the DRP5B ring at the chloroplast division site is coupled to GTP hydrolysis. Furthermore, we established that DRP5B targeting to the chloroplast surface and assembly into a ring structure at the division site are specifically determined by the chloroplast outer envelope membrane (OEM) protein PLASTID DIVISION2 (PDV2), and that DRP5B-OEM dissociation is mainly mediated by PDV1, a paralog of PDV2. Thus, this study suggests that the mechanochemical properties of DRP5B on the chloroplast surface are dynamically regulated by its GTPase activity and major binding partners.

2.
Phys Med Biol ; 64(19): 195013, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31422959

RESUMO

In this study, we propose to remove Moiré image artifact induced by system instabilities in grating-based x-ray interferometry imaging using convolutional neural network (CNN) technique. This method reduces Moiré image artifact in image-domain via a learned image post-processing procedure, rather than developing signal retrieval optimization algorithms to minimize the inconsistencies between acquired phase stepping data and assumed signal model. To achieve this aim, we suggested to train the CNN network using dataset synthesized from both natural images and experimentally acquired Moiré artifact-only images. In particular, a novel approach is developed to generate a large number of various high quality Moiré artifact-only images from finite groups of experimental phase stepping data. Both numerical and experimental results demonstrate that the developed CNN method is able to effectively remove the undesired Moiré image artifact. As a result, the image quality of a practical grating-based x-ray interferometry system can be greatly improved.

3.
J Xray Sci Technol ; 27(5): 949-963, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31381539

RESUMO

PURPOSE: To reduce the cost of positron emission tomography (PET) scanning systems, image reconstruction algorithms for low-sampled data have been extensively studied. However, the current method based on total variation (TV) minimization regularization nested in the maximum likelihood-expectation maximization (MLEM) algorithm cannot distinguish true structures from noise resulting losing some fine features in the images. Thus, this work aims to recover fine features lost in the MLEM-TV algorithm from low-sampled data. METHOD: A feature refinement (FR) approach previously developed for statistical interior computed tomography (CT) reconstruction is applied to PET imaging to recover fine features in this study. The proposed method starts with a constant initial image and the FR step is performed after each MLEM-TV iteration to extract the desired structural information lost during TV minimization. A feature descriptor is specifically designed to distinguish structure from noise and artifacts. A modified steepest descent method is adopted to minimize the objective function. After evaluating the impacts of different patch sizes on the outcome of the presented method, an optimal patch size of 7×7 is selected in this study to balance structure-detection ability and computational efficiency. RESULTS: Applying MLEM-TV-FR algorithm to the simulated brain PET imaging using an emission activity phantom, a standard Shepp-Logan phantom, and mouse results in the increased peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) as comparing to using the conventional MLEM-TV algorithm, as well as the substantial reduction of the used sampling numbers, which improves the computational efficiency. CONCLUSIONS: The presented algorithm can achieve image quality superior to that of the MLEM and MLEM-TV approaches in terms of the preservation of fine structure and the suppression of undesired artifacts and noise, indicating its useful potential for low-sampled data in PET imaging.

4.
J Xray Sci Technol ; 27(3): 573-590, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31177258

RESUMO

Recently, low-dose computed tomography (CT) has become highly desirable due to the increasing attention paid to the potential risks of excessive radiation of the regular dose CT. However, ensuring image quality while reducing the radiation dose in the low-dose CT imaging is a major challenge. Compared to classical filtered back-projection (FBP) algorithms, statistical iterative reconstruction (SIR) methods for modeling measurement statistics and imaging geometry can significantly reduce the radiation dose, while maintaining the image quality in a variety of CT applications. To facilitate low-dose CT imaging, we in this study proposed an improved statistical iterative reconstruction scheme based on the penalized weighted least squares (PWLS) standard combined with total variation (TV) minimization and sparse dictionary learning (DL), which is named as a method of PWLS-TV-DL. To evaluate this PWLS-TV-DL method, we performed experiments on digital phantoms and physical phantoms, and analyzed the results in terms of image quality and calculation. The results show that the proposed method is better than the comparison methods, which indicates the potential of applying this PWLS-TV-DL method to reconstruct low-dose CT images.

5.
J Xray Sci Technol ; 27(4): 739-753, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31227684

RESUMO

X-ray radiation is harmful to human health. Thus, obtaining a better reconstructed image with few projection view constraints is a major challenge in the computed tomography (CT) field to reduce radiation dose. In this study, we proposed and tested a new algorithm that combines penalized weighted least-squares using total generalized variation (PWLS-TGV) and dictionary learning (DL), named PWLS-TGV-DL to address this challenge. We first presented and tested this new algorithm and evaluated it through both data simulation and physical experiments. We then analyzed experimental data in terms of image qualitative and quantitative measures, such as the structural similarity index (SSIM) and the root mean square error (RMSE). The experiments and data analysis indicated that applying the new algorithm to CT data recovered images more efficiently and yielded better results than the traditional CT image reconstruction approaches.

6.
Sensors (Basel) ; 19(1)2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30626109

RESUMO

Aiming at reducing computed tomography (CT) scan radiation while ensuring CT image quality, a new low-dose CT super-resolution reconstruction method based on combining a random forest with coupled dictionary learning is proposed. The random forest classifier finds the optimal solution of the mapping relationship between low-dose CT (LDCT) images and high-dose CT (HDCT) images and then completes CT image reconstruction by coupled dictionary learning. An iterative method is developed to improve robustness, the important coefficients for the tree structure are discussed and the optimal solutions are reported. The proposed method is further compared with a traditional interpolation method. The results show that the proposed algorithm can obtain a higher peak signal-to-noise ratio (PSNR) and structural similarity index measurement (SSIM) and has better ability to reduce noise and artifacts. This method can be applied to many different medical imaging fields in the future and the addition of computer multithreaded computing can reduce time consumption.

7.
Med Phys ; 46(4): 1686-1696, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30697765

RESUMO

PURPOSE: In recent years, health risks concerning high-dose x-ray radiation have become a major concern in dental computed tomography (CT) examinations. Therefore, adopting low-dose computed tomography (LDCT) technology has become a major focus in the CT imaging field. One of these LDCT technologies is downsampling data acquisition during low-dose x-ray imaging processes. However, reducing the radiation dose can adversely affect CT image quality by introducing noise and artifacts in the resultant image that can compromise diagnostic information. In this paper, we propose an artifact correction method for downsampling CT reconstruction based on deep learning. METHOD: We used clinical dental CT data with low-dose artifacts reconstructed by conventional filtered back projection (FBP) as inputs to a deep neural network and corresponding high-quality labeled normal-dose CT data during training. We trained a generative adversarial network (GAN) with Wasserstein distance (WGAN) and mean squared error (MSE) loss, called m-WGAN, to remove artifacts and obtain high-quality CT dental images in a clinical dental CT examination environment. RESULTS: The experimental results confirmed that the proposed algorithm effectively removes low-dose artifacts from dental CT scans. In addition, we showed that the proposed method is efficient for removing noise from low-dose CT scan images compared to existing approaches. We compared the performances of the general GAN, convolutional neural networks, and m-WGAN. Through quantitative and qualitative analysis of the results, we concluded that the proposed m-WGAN method resulted in better artifact correction performance preserving the texture in dental CT scanning. CONCLUSIONS: The image quality evaluation metrics indicated that the proposed method effectively improves image quality when used as a postprocessing technique for dental CT images. To the best of our knowledge, this work is the first deep learning architecture used with a commercial cone-beam dental CT scanner. The artifact correction performance was rigorously evaluated and demonstrated to be effective. Therefore, we believe that the proposed algorithm represents a new direction in the research area of low-dose dental CT artifact correction.


Assuntos
Algoritmos , Odontologia , Processamento de Imagem Assistida por Computador/métodos , Radiografia Dentária/métodos , Tomografia Computadorizada por Raios X/métodos , Artefatos , Humanos , Doses de Radiação , Razão Sinal-Ruído
8.
J Gastroenterol Hepatol ; 34(4): 643-649, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30548242

RESUMO

Chronic diarrhea is one of the most common complaints in clinical practice for both adults and children. The purpose of this study was to assess the commonly used Chinese herbal medicine navel therapy for the treatment of chronic diarrhea (traditional Chinese medicine syndrome of spleen deficiency). The literature search was up to June 2018. Four types of studies (clinical trials, case series, case reports, and experts' experience) researched on Chinese medicine navel therapy used alone or combined with other therapies for the treatment of chronic diarrhea all included. Information on prescriptions, effectiveness, and safety of intervention was collected. Traditional Chinese Medicine Inheritance Support System V2.5 was used to do data analysis. We included 416 studies. All these studies carried out in 194 cities of China. We obtained the most commonly used single herbs, herbal medicine combination, and Chinese patent medicine for both adults and children. The top 3 single herbs were Caryophylli Flos (Dingxiang), Cinnamomi Cortex (Rougui), and Euodiae Fructus (Wuzhuyu). The most frequently used Chinese patent medicines were Ding Gui Infantile Navel Paste and Huoxiang Zhengqi Liquid. The effectiveness assessment was based on clinical trials, but we did not perform a meta-analysis because of different study design and unsatisfactory methodological quality. No serious adverse reaction happened in original studies. The application of Chinese medicine navel therapy could be one of the ideal treatments for chronic diarrhea in the future, especially for children. However, high-quality studies are very needed to provide clear evidence.


Assuntos
Diarreia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Administração Tópica , Adulto , Criança , China , Doença Crônica , Bases de Dados Bibliográficas , Combinação de Medicamentos , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa , Fitoterapia , Resultado do Tratamento
9.
Plant Cell ; 30(8): 1807-1823, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29967285

RESUMO

Chloroplasts replicate by binary fission, a process driven by ring-like dynamic division machinery at mid-chloroplast. In Arabidopsis thaliana, the first molecular assembly of this machinery, the Z-ring, forms via the association of FtsZ1 and FtsZ2 heteropolymers with the inner envelope membrane through the membrane-tethering protein ACCUMULATION AND REPLICATION OF CHLOROPLASTS6 (ARC6). Spatial control of Z-ring assembly ensures the correct placement of the division machinery and, therefore, symmetric chloroplast division. The plant-specific protein MULTIPLE CHLOROPLAST DIVISION SITE1 (MCD1) plays a role in Z-ring positioning and chloroplast division site placement, but its mechanism of action is unknown. Here, we provide evidence that MCD1 is a bitopic inner membrane protein whose C terminus faces the chloroplast stroma. Interaction analysis showed that MCD1 and ARC6 directly interact in the stroma and that MCD1 binds to FtsZ2 in an ARC6-dependent manner. These results are consistent with the in vivo observation that ARC6 influences the localization of MCD1 to membrane-tethered FtsZ filaments. Additionally, we found that MCD1 is required for the regulation of Z-ring positioning by ARC3 and MinE1, two components of the chloroplast Min (minicell) system, which negatively regulates Z-ring placement. Together, our findings indicate that MCD1 is part of the chloroplast Min system that recognizes membrane-tethered FtsZ filaments during chloroplast division-ring positioning.


Assuntos
Arabidopsis/metabolismo , Cloroplastos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/genética , Citoesqueleto/genética , Citoesqueleto/metabolismo , Replicação do DNA/genética , Replicação do DNA/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
10.
Sci Rep ; 8(1): 8799, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29892023

RESUMO

In this paper, a single-computed tomography (CT) image super-resolution (SR) reconstruction scheme is proposed. This SR reconstruction scheme is based on sparse representation theory and dictionary learning of low- and high-resolution image patch pairs to improve the poor quality of low-resolution CT images obtained in clinical practice using low-dose CT technology. The proposed strategy is based on the idea that image patches can be well represented by sparse coding of elements from an overcomplete dictionary. To obtain similarity of the sparse representations, two dictionaries of low- and high-resolution image patches are jointly trained. Then, sparse representation coefficients extracted from the low-resolution input patches are used to reconstruct the high-resolution output. Sparse representation is used such that the trained dictionary pair can reduce computational costs. Combined with several appropriate iteration operations, the reconstructed high-resolution image can attain better image quality. The effectiveness of the proposed method is demonstrated using both clinical CT data and simulation image data. Image quality evaluation indexes (root mean squared error (RMSE) and peak signal-to-noise ratio (PSNR)) indicate that the proposed method can effectively improve the resolution of a single CT image.

11.
Anal Chim Acta ; 978: 55-60, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28595727

RESUMO

Capillary electrophoresis (CE) is a powerful separation technique with advantages over HPLC in terms of separation efficiency, speed, and cost. However, CE suffers in poor reproducibility in quantitative chemical analysis, which is one of major drawbacks preventing its widespread use in routine analytical laboratories. Here we report a novel strategy to enhance the quantitative capability of flow-gated CE. The platform integrated dual flow branches to respectively supply a sample and its standard additions that were then alternately injected into a single capillary for rapid separations (typically 20-90 s). A micro-fabricated switch was used to enable the alternate injections. It was assumed that the analytical system maintained constant conditions during neighboring injections that served as external self-standards for quantitation. This strategy was expected to reduce uncertainties caused by the fluctuation in capillary conditions and the drift of detection systems. Experimental results demonstrated that the dual-branch flow-gated CE coupled with alternate injections significantly improved the reproducibility with respect to peak height ratios under deliberate variations in injection volumes, separation voltages, optical focusing, and laser power; and thus the interday precision was ensured. To demonstrate its applicability, cyanide and amino acids in human urine were quantified rapidly with the one-point standard addition method after fluorogenic derivatization with naphthalene-2,3-dicarboxaldehyde (NDA), and the measurement accuracy was validated by determining the recovery of standard cyanide added to a urinary matrix. This strategy would be valuable to enable the quantitative capability of flow-gated CE in the measurements of a broad range of analytes, especially those lacking suited internal standards.


Assuntos
Eletroforese Capilar , Urinálise/métodos , Aminoácidos/análise , Cianetos/análise , Humanos , Injeções , Reprodutibilidade dos Testes
12.
Electrophoresis ; 38(3-4): 507-512, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27747885

RESUMO

LIF detection often requires labeling of analytes with fluorophores; and fast fluorescent derivatization is valuable for high-throughput analysis with flow-gated CE. Here, we report a fast fluorescein-labeling scheme for amino acid neurotransmitters, which were then rapidly separated and detected in flow-gated CE. This scheme was based on the reaction between primary amines and o-phthalaldehyde in the presence of a fluorescent thiol, 2-((5-fluoresceinyl)aminocarbonyl)ethyl mercaptan (FACE-SH). The short reaction time (<30 s) was suited for on-line mixing and derivatization that was directly coupled with flow-gated CE for rapid electrophoretic separation and sensitive LIF detection. To maintain the effective concentration of reactive FACE-SH, Tris(2-carboxyethyl)phosphine was added to the derivatization reagents to prevent thiol loss due to oxidation. This labeling scheme was applied to the detection of neurotransmitters by coupling in vitro microdialysis with online derivatization and flow-gated CE. It is also anticipated that this fluorophore tagging scheme would be valuable for on-chip labeling of proteins retained on support in SPE.


Assuntos
Aminoácidos/análise , Eletroforese Capilar/métodos , Corantes Fluorescentes/química , Neurotransmissores/análise , o-Ftalaldeído/química , Fluoresceínas/química , Humanos , Compostos de Sulfidrila/química
13.
J Chromatogr A ; 1450: 112-20, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27156734

RESUMO

Flow-gated capillary electrophoresis (CE) coupled with microdialysis has become an important tool for in vivo bioanalytical measurements because it is capable of performing rapid and efficient separations of complex biological mixtures thus enabling high temporal resolution in chemical monitoring. However, the limit of detection (LOD) is often limited to a micro- or nano-molar range while many important target analytes have picomolar or sub-nanomolar levels in brain and other tissues. To enhance the capability of flow-gated CE for catecholamine detection, a novel and simple on-line sample preconcentration method was developed exclusively for fluorescent derivatives of catecholamines that were fluorogenically derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide. The effective preconcentration coupled with the sensitive laser-induced fluorescence (LIF) detection lowered the LOD down to 20pM for norepinephrine (NE) and 50pM for dopamine (DA) at 3-fold of S/N ratio, and the signal enhancement was estimated to be over 100-fold relative to normal injection when standard analytes were dissolved in artificial cerebrospinal fluid (aCSF). The basic focusing principle is novel since the sample plug contains borate while the background electrolyte (BGE) is void of borate. This strategy took advantage of the complexation between diols and borate, through which one negative charge was added to the complex entity. The sample derivatization mixture was electrokinetically injected into a capillary via the flow-gated injection, and then NE and DA derivatives were selectively focused to a narrow zone by the reversible complexation. Separation of NE and DA derivatives was executed by incoming surfactants of cholate and deoxycholate mixed in the front BGE plug. This on-line preconcentration method was finally applied to the detection of DA in rat cerebrospinal fluid (CSF) via microdialysis and on-line derivatization. It is anticipated that the method would be valuable for in vivo monitoring of DA and NE in various brain regions of live animals on flow-gated CE or microchip platforms.


Assuntos
Dopamina/líquido cefalorraquidiano , Dopamina/química , Eletroforese Capilar/métodos , Norepinefrina/líquido cefalorraquidiano , Norepinefrina/química , Animais , Boratos , Química Encefálica , Cianetos/química , Eletrólitos/química , Eletroforese Capilar/instrumentação , Limite de Detecção , Procedimentos Analíticos em Microchip , Microdiálise , Naftalenos/química , Ratos , Tensoativos/química
14.
J Chromatogr A ; 1414: 158-62, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26342870

RESUMO

Cyanides are poisonous chemicals that widely exist in nature and industrial processes as well as accidental fires. Rapid and accurate determination of cyanide exposure would facilitate forensic investigation, medical diagnosis, and chronic cyanide monitoring. Here, a rapid and direct method was developed for the determination of cyanide ions in urinary samples. This technique was based on an integrated capillary electrophoresis system coupled with laser-induced fluorescence (LIF) detection. Cyanide ions were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) and a primary amine (glycine) for LIF detection. Three separate reagents, NDA, glycine, and cyanide sample, were mixed online, which secured uniform conditions between samples for cyanide derivatization and reduced the risk of precipitation formation of mixtures. Conditions were optimized; the derivatization was completed in 2-4min, and the separation was observed in 25s. The limit of detection (LOD) was 4.0nM at 3-fold signal-to-noise ratio for standard cyanide in buffer. The cyanide levels in urine samples from smokers and non-smokers were determined by using the method of standard addition, which demonstrated significant difference of cyanide levels in urinary samples from the two groups of people. The developed method was rapid and accurate, and is anticipated to be applicable to cyanide detection in waste water with appropriate modification.


Assuntos
Cianetos/análise , Tampões (Química) , Cianetos/química , Eletroforese Capilar , Humanos , Indicadores e Reagentes , Limite de Detecção , Naftalenos/química , Razão Sinal-Ruído
15.
J Chromatogr A ; 1324: 231-7, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24331370

RESUMO

Integrated microfluidic systems coupled with electrophoretic separations have broad application in biologic and chemical analysis. Interfaces for the connection of various functional parts play a major role in the performance of a system. Here, we developed a rapid prototyping method to fabricate monolithic poly(dimethylsiloxane) (PDMS) interfaces for flow-gated injection, online reagent mixing, and tube-to-tube connection in an integrated capillary electrophoresis (CE) system. The basic idea was based on the properties of PDMS: elasticity, transparency, and suitability for prototyping. The molds for these interfaces were prepared by using commercially available stainless steel wires and nylon lines or silica capillaries. A steel wire was inserted through the diameter of a nylon line and a cross format was obtained as the mold for PDMS casting of flow gates and 4-way mixers. These interfaces accommodated tubing connection through PDMS elasticity and provided easy visual trouble shooting. The flow gate used smaller channel diameters, thus reducing flow rate by 25-fold for effective gating compared with mechanically machined counterparts. Both PDMS mixers and the tube-to-tube connectors could minimize the sample dead volume by using an appropriate capillary configuration. As a whole, the prototyped PDMS interfaces are reusable, inexpensive, convenient for connection, and robust when integrated with the CE detection system. Therefore, these interfaces could see potential applications in CE and CE-coupled systems.


Assuntos
Dimetilpolisiloxanos/química , Eletroforese Capilar/instrumentação , Nylons/química , Aminoácidos/isolamento & purificação , Eletroforese Capilar/métodos , Dióxido de Silício/química
16.
J Xray Sci Technol ; 20(3): 351-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22948356

RESUMO

A mathematical derivation was conducted to illustrate that exact 3D image reconstruction could be achieved for z-homogeneous phantoms from data acquired with 2D general trajectories using the back projection filtration (BPF) algorithm. The conclusion was verified by computer simulation and experimental result with a circular scanning trajectory. Furthermore, the effect of the non-uniform degree along z-axis of the phantoms on the accuracy of the 3D reconstruction by BPF algorithm was investigated by numerical simulation with a gradual-phantom and a disk-phantom. The preliminary result showed that the performance of BPF algorithm improved with the z-axis homogeneity of the scanned object.


Assuntos
Algoritmos , Tomografia Computadorizada de Feixe Cônico/métodos , Simulação por Computador , Tomografia Computadorizada de Feixe Cônico/instrumentação , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas
17.
IEEE Trans Inf Technol Biomed ; 15(4): 655-60, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21659036

RESUMO

Micro-CT with a high spatial resolution in combination with computer-based-reconstruction techniques is considered a powerful tool for morphological study of insects. The quality of CT images crucially depends on the precise knowledge of the scan geometry of the micro-CT system. In this paper, we have proposed a method to calculate the deviation of rotating axis for compensating deficiency of existing methods. A practical application of this geometric calibration method of the micro-CT system for insect imaging is presented. We have performed the computer-simulation study and experimental study with our prototype micro-CT system. The results demonstrate that the proposed technique is accurate and robust. In addition, we have evaluated the imaging characteristics of the detector in terms of modulation-transfer function (MTF). Finally, insect imaging performance and image reconstruction from data acquired with different energies are presented.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Insetos/anatomia & histologia , Microtomografia por Raio-X/normas , Algoritmos , Animais , Calibragem , Imagens de Fantasmas , Microtomografia por Raio-X/instrumentação , Microtomografia por Raio-X/métodos
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