1,589 research outputs found
Three-Dimensional Microscopic Image Reconstruction Based on Structured Light Illumination
In this paper, we propose and experimentally demonstrate a three-dimensional (3D) microscopic system that reconstructs a 3D image based on structured light illumination. The spatial pattern of the structured light changes according to the profile of the object, and by measuring the change, a 3D image of the object is reconstructed. The structured light is generated with a digital micro-mirror device (DMD), which controls the structured light pattern to change in a kHz rate and enables the system to record the 3D information in real time. The working distance of the imaging system is 9 cm at a resolution of 20 μm. The resolution, working distance, and real-time 3D imaging enable the system to be applied in bridge and road crack examinations, and structure fault detection of transportation infrastructures
Spectrophotometric detection of uric acid with enzyme-like reaction mediated 3,3′,5,5′-tetramethylbenzidine oxidation
ABSTRACT. WO3 nanosheets (NSs) were prepared and characterized by X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The obtained WO3 NSs exhibited peroxidase-like catalytic activity, which can catalyze H2O2 to oxidize 3,3 ',5,5 '-tetramethylbenzidine (TMB) to generate oxidized TMB (oxTMB) with an absorption peak centered at 652 nm. Based on this, a facile method for the spectrophotometric determination of H2O2 was established. Under the selected conditions, the increase in absorbance of oxTMB enabled the detection of H2O2 ranging from 2.0 to 180 μM. Considering the fact that H2O2 is one of the products of urate oxidase (UAO)-catalyzed uric acid (UA) oxidation, a convenient method for the selective determination of UA was further developed with the help of UV–vis spectrophotometer. The increase of absorbance at 652 nm showed a linear response to UA concentration over the range of 2.0–180 μM. The limit of detection for UA was as low as 1.25 μM. More importantly, the proposed method was applied to the determination of UA in serum samples with satisfactory results.
KEY WORDS: Spectrophotometric, WO3 nanosheets, Uric acid, Determination
Bull. Chem. Soc. Ethiop. 2023, 37(1), 11-21.
DOI: https://dx.doi.org/10.4314/bcse.v37i1.2 
Spatial and Modal Optimal Transport for Fast Cross-Modal MRI Reconstruction
Multi-modal magnetic resonance imaging (MRI) plays a crucial role in
comprehensive disease diagnosis in clinical medicine. However, acquiring
certain modalities, such as T2-weighted images (T2WIs), is time-consuming and
prone to be with motion artifacts. It negatively impacts subsequent multi-modal
image analysis. To address this issue, we propose an end-to-end deep learning
framework that utilizes T1-weighted images (T1WIs) as auxiliary modalities to
expedite T2WIs' acquisitions. While image pre-processing is capable of
mitigating misalignment, improper parameter selection leads to adverse
pre-processing effects, requiring iterative experimentation and adjustment. To
overcome this shortage, we employ Optimal Transport (OT) to synthesize T2WIs by
aligning T1WIs and performing cross-modal synthesis, effectively mitigating
spatial misalignment effects. Furthermore, we adopt an alternating iteration
framework between the reconstruction task and the cross-modal synthesis task to
optimize the final results. Then, we prove that the reconstructed T2WIs and the
synthetic T2WIs become closer on the T2 image manifold with iterations
increasing, and further illustrate that the improved reconstruction result
enhances the synthesis process, whereas the enhanced synthesis result improves
the reconstruction process. Finally, experimental results from FastMRI and
internal datasets confirm the effectiveness of our method, demonstrating
significant improvements in image reconstruction quality even at low sampling
rates
Diaquabis(5-methylpyrazine-2-carboxylato-κ2 N 1,O)cobalt(II) dihydrate
In the title complex, [Co(C6H5N2O2)2(H2O)2]·2H2O, the coordination geometry of the Co2+ cation is distorted octahedral, with two N atoms and two O atoms from two 5-methylpyrazine-2-carboxylate ligands in the equatorial plane. The two remaining coordination sites are occupied by two water molecules. In addition, there are two uncoordinated water molecules in the asymmetric unit. The crystal structure is stabilized by a network of O—H⋯O and O—H⋯N hydrogen-bonding interactions, forming a three-dimensional structure
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