CeO2 supported MOFs derived LaBxFeyO3 (B=Mn, Co) perovskite catalysts for degradation of toluene.

In this work, LaCoO3 and LaMnO3 perovskites with the higher specific surface area were synthesized using MOFs as precursor, then, the composite catalysts CeO2-LaCoxFeyO3 and CeO2-LaMnxFeyO3 were prepared by using CeO2 as support and Fe element doping LaCoO3 and LaMnO3, respectively. The as-prepared samples were characterized by XRD, SEM, XPS, H2-TPR, and N2 physisorption techniques. Subsequently, toluene was used as the probe molecule for volatile organic compounds (VOCs) to test the catalytic activity of these as-prepared catalysts. The results show that the initial reaction temperature for toluene oxidation on supported perovskite catalysts is lower. Among which, CeO2-LaCo0.25Fe0.75O3 (T90=215 °C, T90: the temperature corresponding to 90% conversion of toluene) and CeO2-LaMn0.25Fe0.75O3 (T90=205 °C) catalysts show the best catalytic performance. Therefore, the supported perovskite prepared in this study has the advantages of high specific surface area, abundant oxygen vacancies, and excellent oxygen mobility, which makes it exhibit better performance in VOCs catalytic oxidation.

Nanomaterials-based electrochemical sensors for the detection of natural antioxidants in food and biological samples: research progress.

Antioxidants are healthy substances that are beneficial to the human body and exist mainly in natural and synthetic forms. Among many kinds of antioxidants, the natural antioxidants have great applications in many fields such as food chemistry, medical care, and clinical application. In recent years, many efforts have been made for the determination of natural antioxidants. Nano-electrochemical sensors combining electrochemistry and nanotechnology have been widely used in the determination of natural antioxidants due to their unique advantages. Therefore, a large number of nanomaterials such as metal oxide, carbon materials, and conducting polymer have attracted much attention in the field of electrochemical sensors due to their good catalytic effect and stable performance. This review mainly introduces the construction of electrochemical sensors based on different nanomaterials, such as metallic nanomaterials, metal oxide nanomaterials, carbon nanomaterials, metal-organic frameworks, polymer nanomaterials, and other nanocomposites, and their application to the detection of natural antioxidants, including ascorbic acid, phenolic acids, flavonoid, tryptophan, citric acid, and other natural antioxidants. In the end, the limitations of the existing nano-sensing technology, the latest development trend, and the application prospect for various natural antioxidant substances are summarized and analyzed. We expect that this review will be helpful to researchers engaged in electrochemical sensors.

[Speciation Distribution and Risk Assessment of Heavy Metals in Sediments from the Yitong River City Area].

The total content and chemical speciation of Cd, Cr, Cu, Ni, Pb, and Zn in seven short cores sampled from the Yitong River from Changchun City were analyzed to assess the pollution levels and potential ecological risks of heavy metals in the sediments. The results demonstrated that the total contents of Cd, Cr, Cu, Ni, Pb, and Zn in sediments were 0.10-1.18, 23.57-66.35, 11.27-43.95, 10.78-29.82, 15.02-60.81, and 54.27-175.83 mg·kg-1, respectively. The acid-soluble fraction of Cd varied from 42.1% to 51.28%, whereas Cr, Ni, and Zn were mainly found in the residual fraction; their mass fractions were 63.54%-79.91%, 35.16%-53.75%, and 27.55%-57.55%, respectively. The vertical results of pollution degree and ecological risk assessment indicated that the studied sediment was polluted by Cd, Cu, Pb, and Zn, and the ecological risk of Cd was the highest, followed by Zn and Cu. Each group of metals in each core showed a similar vertical variation, and the ecological risk of metals in sediment of 4-8 cm depth was relatively high. Cd, Zn, and Pb in the sediments of Yitong River were mainly from industrial pollution and municipal sewage discharge, and Cu could be attributed to both natural processes and human activities, whereas Cr and Ni may be attributed to natural processes.

Fluorescence Molecular Tomography Based on Group Sparsity Priori for Morphological Reconstruction of Glioma.

OBJECTIVE: Fluorescence molecular tomography (FMT) is an important tool for life science, which can noninvasive real-time three-dimensional (3-D) visualization for fluorescence source location. FMT is widely used in tumor research due to its high-sensitive and low cost. However, the reconstruction of FMT is difficult. Although the reconstruction methods of FMT have developed rapidly in recent years, the morphological reconstruction of FMT is still a challenge problem. Thus, the purpose of this study is to realize the morphological reconstruction performance of FMT in glioma research. METHODS: In this study, group sparsity was used as a new priori information for FMT. Besides sparsity, group sparsity also takes the group structure of the fluorescent sources, which can maintain the morphological information of the sources. Fused LASSO method (FLM) was proved it can efficiently model the group sparsity prior. Thus, we utilize FLM to reconstruct the morphological information of glioma. Furthermore, to reduce the influence of the high scattering of skull, we modified the FLM for improving the accuracy of morphological reconstruction. RESULTS: Glioma numerical simulation model and in vivo glioma model were established to evaluate the performance of morphological reconstruction of the proposed method. The results demonstrated that the proposed method was efficient to reconstruct the morphological information of glioma. CONCLUSION: Group sparsity priori can effectively improve the morphological accuracy of FMT reconstruction. SIGNIFICANCE: Group sparsity can maintain the morphological information of fluorescent sources effectively, which has great application potential in FMT. The group sparsity based methods can realize the morphological reconstruction, which is of great practical significance in tumor research.

Effects of the pyrolysis temperature on the biotoxicity of Phyllostachys pubescens biochar in the aquatic environment.

The use of biochar as an adsorbent for environmental remediation has been attracting increasing interest. However, biochar can contain contaminants such as polycyclic aromatic hydrocarbons (PAHs) and metals (e.g., Cu, Pb, and Zn). We prepared Phyllostachys pubescens biochars at temperatures between 400 and 700 °C. The biochars were used in bioassays using Vibrio qinghaiensis Q67, Daphnia magna, Pseudokirchneriella subcapitata, and Limnodrilus hoffmeisteri to characterize the toxicities and effects of the biochars. The PAH, Cu, Pb, and Zn contents of the biochars were 8.59-14.67, 1.82-3.26, 1.17-3.53, and 8.76-16.47 mg/kg, respectively. The biochars gave maximum P. subcapitata, D. magna, and V. qinghaiensis Q67 inhibition rates of 6.47%, 6.70%, and 29.87%, respectively. The biochars produced at high pyrolysis temperatures (≥600 °C) had low acute biotoxicities to L. hoffmeisteri and barely affected L. hoffmeisteri biomass, reproduction, and lipid content. The biochars may therefore be suitable for sediment remediation.

Reconstruction of Fluorescence Molecular Tomography via a Fused LASSO Method Based on Group Sparsity Prior.

OBJECTIVE: The aim of this paper is to improve the reconstruction accuracy in both position and source region of fluorescence molecular tomography (FMT). METHODS: The reconstruction of the FMT is challenging due to its serious ill-posedness and ill-condition. Currently, to obtain the fluorescent sources accurately, more a priori information of the fluorescent sources is utilized and more efficient and practical methods are proposed. In this paper, we took the group sparsity of the fluorescent sources as a new type of priori information in the FMT, and proposed the fused LASSO method (FLM) for FMT. The FLM based on group sparsity prior not only takes advantage of the sparsity of the fluorescent sources, but also utilizes the structure of the sources, thus making the reconstruction results more accuracy and morphologically similar to the sources. To further improve the reconstruction efficiency, we adopt Nesterov's method to solve the FLM. RESULTS: Both heterogeneous numerical simulation experiments and in vivo mouse experiments were carried out to verify the property of the FLM. The results have verified the superiority of the FLM over conventional methods in tumor detection and tumor morphological reconstruction. Furthermore, the in vivo experiments had demonstrated that the FLM has great potential in preclinical application of the FMT. SIGNIFICANCE: The reconstruction method based on group sparsity prior has a great potential in the FMT study, it can further improve the reconstruction quality, which has practical significance in preclinical research.

Corrections for "Bioluminescence Tomography Based on Gaussian Weighted Laplace Prior Regularization for Morphological Imaging of Glioma".

In [1], the affiliation for Y. Gao, K. Wang and J. Tian should have appeared as follows:.

Reconstruction method for fluorescence molecular tomography based on L1-norm primal accelerated proximal gradient.

Fluorescence molecular tomography (FMT) has been widely used in preclinical tumor imaging, which enables three-dimensional imaging of the distribution of fluorescent probes in small animal bodies via image reconstruction method. However, the reconstruction results are usually unsatisfactory in the term of robustness and efficiency because of the ill-posed and ill-conditioned of FMT problem. In this study, an FMT reconstruction method based on primal accelerated proximal gradient (PAPG) descent and L1-norm regularized projection (L1RP) is proposed. The proposed method utilizes the current and previous iterations to obtain a search point at each iteration. To achieve fast convergence, the PAPG method is applied to efficiently solve the search point, and then L1RP is performed to obtain the robust and accurate reconstruction. To verify the performance of the proposed method, simulation experiments are conducted. The comparative results revealed that it held advantages of robustness, accuracy, and efficiency in FMT reconstructions. Furthermore, a phantom experiment and an in vivo mouse experiment were also performed, which proved the potential and feasibility of the proposed method for practical applications.

Corrections to "Bioluminescence Tomography Based on Gaussian Weighted Laplace Prior Regularization for Morphological Imaging of Glioma".

The correct affiliation for Yuan Gao, Kun Wang, and Jie Tian is as follows.

Sparse Reconstruction of Fluorescence Molecular Tomography Using Variable Splitting and Alternating Direction Scheme.

PURPOSE: Fluorescence molecular tomography (FMT) is a novel imaging modality for three-dimensional preclinical research and has many potential applications for drug therapy evaluation and tumor diagnosis. However, FMT presents an ill-conditioned and ill-posed inverse problem, which is a challenge for its tomography reconstruction. Due to the importance of FMT reconstruction, it is valuable and necessary to develop further practical reconstruction methods for FMT. PROCEDURES: In this study, an efficient method using variable splitting strategy as well as alternating direction strategy (VSAD) was proposed for FMT reconstruction. In this method, the variable splitting strategy and the augmented Lagrangian function were first introduced to obtain an equivalent optimization formulation of the original problem. Then, the alternating direction scheme was used to solve the optimization problem and to accelerate its convergence. To examine the property of the VSAD method, three numerical simulation experiments (accuracy assessment experiment, robustness assessment experiment, and reconstruction speed assessment experiment) were performed and analyzed. RESULTS: The results indicated that the reconstruction accuracy, the reconstruction robustness, and the reconstruction speed of FMT were satisfactory by using the proposed VSAD method. Two in vivo studies, which were conducted by using two nude mouse models, further confirmed the advantages of the proposed method. CONCLUSIONS: The results indicated that the proposed VSAD algorithm is effective for FMT reconstruction. It was accurate, robust, and efficient for FMT imaging and was feasibly applied for in vivo FMT applications.

Bioluminescence Tomography Based on Gaussian Weighted Laplace Prior Regularization for In Vivo Morphological Imaging of Glioma.

Bioluminescence tomography (BLT) is a powerful non-invasive molecular imaging tool for in vivo studies of glioma in mice. However, because of the light scattering and resulted ill-posed problems, it is challenging to develop a sufficient reconstruction method, which can accurately locate the tumor and define the tumor morphology in three-dimension. In this paper, we proposed a novel Gaussian weighted Laplace prior (GWLP) regularization method. It considered the variance of the bioluminescence energy between any two voxels inside an organ had a non-linear inverse relationship with their Gaussian distance to solve the over-smoothed tumor morphology in BLT reconstruction. We compared the GWLP with conventional Tikhonov and Laplace regularization methods through various numerical simulations and in vivo orthotopic glioma mouse model experiments. The in vivo magnetic resonance imaging and ex vivo green fluorescent protein images and hematoxylin-eosin stained images of whole head cryoslicing specimens were utilized as gold standards. The results demonstrated that GWLP achieved the highest accuracy in tumor localization and tumor morphology preservation. To the best of our knowledge, this is the first study that achieved such accurate BLT morphological reconstruction of orthotopic glioma without using any segmented tumor structure from any other structural imaging modalities as the prior for reconstruction guidance. This enabled BLT more suitable and practical for in vivo imaging of orthotopic glioma mouse models.

Novel method for determination of optical rotatory dispersion spectrum by using line scan CCD.

A novel method is presented for rapid measurement of optical rotatory dispersion (ORD). Light passes through a polarizer, sample and analyzer, to a transmission grating that disperses the collimated light beam. A step-motor rotating stage controlled by a digital signal processor changes the analyzer orientation. The light power is measured by a charge-coupled device (CCD) after each rotating-stage step. The optical rotation angle for each wavelength is determined from the shift between two Malus curves obtained from each CCD pixel. The ORD spectrum is obtained by transforming the optical rotation angle into specific rotation. The ORD spectrum for a standard quartz tube demonstrates good continuity and agreement with reference data.

Precise integrin-targeting near-infrared imaging-guided surgical method increases surgical qualification of peritoneal carcinomatosis from gastric cancer in mice.

Peritoneal carcinomatosis from gastric cancer represents a common recurrent gastric cancer that seriously affects the survival, prognosis, and quality of life of patients at its advanced stage. In recent years, complete cytoreduction surgery in combination with hyperthermic intraperitoneal chemotherapy has been demonstrated to improve the survival and prognosis of patients with malignant tumors including peritoneal carcinomatosis from gastric cancer. Establishing viable methods of accurately assessing the tumor burden in patients with peritoneal carcinoma and correctly selecting suitable patients in order to improve cytoreduction surgical outcomes and reduce the risk of postoperative complications has become a challenge in the field of peritoneal carcinoma research. Here, we investigated peritoneal carcinomatosis from gastric cancer in a mouse model by using our self-developed surgical navigation system that combines optical molecular imaging with an integrin-targeting Arg-Gly-Asp-indocyanine green (RGD-ICG) molecular probe. The results showed that our diagnostic method could achieve a sensitivity and specificity of up to 93.93% and 100%, respectively, with a diagnostic index (DI) of 193.93% and diagnostic accuracy rate of 93.93%.Furthermore, the minimum tumor diameter measured during the surgery was 1.8 mm and the operative time was shortened by 3.26-fold when compared with the conventionally-treated control group. Therefore, our surgical navigation system that combines optical molecular imaging with an RGD-ICG molecular probe, could improve the diagnostic accuracy rate for peritoneal carcinomatosis from gastric cancer, shorten the operative time, and improve the quality of the cytoreduction surgery for peritoneal carcinomatosis from gastric cancer, thus providing a solid foundation for its future clinical development and application.

Compactly Supported Radial Basis Function-Based Meshless Method for Photon Propagation Model of Fluorescence Molecular Tomography.

Fluorescence Molecular Tomography (FMT) is a powerful imaging modality for the research of cancer diagnosis, disease treatment and drug discovery. Via three-dimensional (3-D) imaging reconstruction, it can quantitatively and noninvasively obtain the distribution of fluorescent probes in biological tissues. Currently, photon propagation of FMT is conventionally described by the Finite Element Method (FEM), and it can obtain acceptable image quality. However, there are still some inherent inadequacies in FEM, such as time consuming, discretization error and inflexibility in mesh generation, which partly limit its imaging accuracy. To further improve the solving accuracy of photon propagation model (PPM), we propose a novel compactly supported radial basis functions (CSRBFs)-based meshless method (MM) to implement the PPM of FMT. We introduced a series of independent nodes and continuous CSRBFs to interpolate the PPM, which can avoid complicated mesh generation. To analyze the performance of the proposed MM, we carried out numerical heterogeneous mouse simulation to validate the simulated surface fluorescent measurement. Then we performed an in vivo experiment to observe the tomographic reconstruction. The experimental results confirmed that our proposed MM could obtain more similar surface fluorescence measurement with the golden standard (Monte-Carlo method), and more accurate reconstruction result was achieved via MM in in vivo application.

Research of optical rotation measurement system based on centroid algorithm.

An optical rotation measurement system based on digital signal processor, modulated laser, and step motor rotating stage is established. Centroid algorithm featured fast and simple calculation is introduced to process light signals with or without sample to obtain the optical rotating angle through the step difference between two centroids. The system performance is proved experimentally with standard quartz tubes and glucose solutions. After various measurements, the relative error and precision of the system are determined to 0.4% and 0.004°, which demonstrates the reliable repeatability and high accuracy of whole measurement system.

Novel l 2,1-norm optimization method for fluorescence molecular tomography reconstruction.

Fluorescence molecular tomography (FMT) is a promising tomographic method in preclinical research, which enables noninvasive real-time three-dimensional (3-D) visualization for in vivo studies. The ill-posedness of the FMT reconstruction problem is one of the many challenges in the studies of FMT. In this paper, we propose a l 2,1-norm optimization method using a priori information, mainly the structured sparsity of the fluorescent regions for FMT reconstruction. Compared to standard sparsity methods, the structured sparsity methods are often superior in reconstruction accuracy since the structured sparsity utilizes correlations or structures of the reconstructed image. To solve the problem effectively, the Nesterov's method was used to accelerate the computation. To evaluate the performance of the proposed l 2,1-norm method, numerical phantom experiments and in vivo mouse experiments are conducted. The results show that the proposed method not only achieves accurate and desirable fluorescent source reconstruction, but also demonstrates enhanced robustness to noise.

Meshless reconstruction method for fluorescence molecular tomography based on compactly supported radial basis function.

Fluorescence molecular tomography (FMT) is a promising tool in the study of cancer, drug discovery, and disease diagnosis, enabling noninvasive and quantitative imaging of the biodistribution of fluorophores in deep tissues via image reconstruction techniques. Conventional reconstruction methods based on the finite-element method (FEM) have achieved acceptable stability and efficiency. However, some inherent shortcomings in FEM meshes, such as time consumption in mesh generation and a large discretization error, limit further biomedical application. In this paper, we propose a meshless method for reconstruction of FMT (MM-FMT) using compactly supported radial basis functions (CSRBFs). With CSRBFs, the image domain can be accurately expressed by continuous CSRBFs, avoiding the discretization error to a certain degree. After direct collocation with CSRBFs, the conventional optimization techniques, including Tikhonov, L1-norm iteration shrinkage (L1-IS), and sparsity adaptive matching pursuit, were adopted to solve the meshless reconstruction. To evaluate the performance of the proposed MM-FMT, we performed numerical heterogeneous mouse experiments and in vivo bead-implanted mouse experiments. The results suggest that the proposed MM-FMT method can reduce the position error of the reconstruction result to smaller than 0.4 mm for the double-source case, which is a significant improvement for FMT.