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• This paper presents a novel approach by integrating the holographic double exposure method with image processing. We achieve both qualitative and quantitative detection of internal defects in objects. • The experimental results presented in this paper unequivocally demonstrate the efficacy and viability of the proposed method in detecting internal defects within objects. • This method requires the recording of just two holograms in distinct states in order to acquire the information regarding internal defects. • Compared with traditional methods, this method can obtain defect information faster and more accurately. Recent years have witnessed an increasing demand for high-quality materials in all industries; therefore, internal defects are disastrous for maintaining the required industrial quality. In this study, qualitative and quantitative analysis of the internal defects of objects is conducted using differential holographic double-exposure and digital image processing techniques. The objects underwent thermal loading, and two holograms were recorded at different temperatures. Internal defects were qualitatively and quantitatively analysed by processing and comparing the interference fringes produced by removing and reproducing the two holograms via digital image processing. The fringes at the location of the sample defects differed from the changes in surrounding fringes, and the defect size was determined by fitting the fringe region at the defect location. Finally, the experimental results were validated using a structured light 3D measurement method to identify the size of the defects. Interesting results were obtained, with a maximum error of 9.637 % for irregular defects and a minimum error of 3.528 % for regular defects. [ABSTRACT FROM AUTHOR]

• Proposed a one-six network for phase calculation. • This article proposes for the first time a one-six network combined with binocular fringe projection for 3D reconstruction. • The method proposed in this article can effectively reduce the drawback of requiring a large number of fringe patterns in binocular fringe projection, achieving high-speed and high-precision measurement. • The network proposed in this article can fuse more feature information and achieve better and faster fitting by setting appropriate drop values. • This article uses composite color fringe patterns, which have more feature information and can provide a better learning for the network. At present, deep learning plays a crucial role in structured light 3D reconstruction. Further, in the field of fringe projection profilometry, learning 3D features from fringes and performing 3D reconstruction are being studied by many researchers. This paper combines deep learning with binocular fringe projection, uses three channels to form a single-composite-color fringe pattern for three different frequencies as the input, and predicts the numerator and denominator required to solve the wrapped phase of the object. The wrapped phase is calculated using an arctangent function. The absolute phase is obtained by unwrapping the multi-frequency heterodyne method, and the absolute phase of the left and right cameras is matched to obtain a disparity map. The parameters obtained through camera calibration can restore the 3D shape of the object, which greatly reduces the number of fringes required; accuracy close to the phase of the training set is achieved. Finally, the experimental results demonstrate the feasibility of this approach. [ABSTRACT FROM AUTHOR]

• This paper for the first time, proposes phase-shifting segmented phase coding and combines bidirectional coding and complementary phase coding. • The application of the phase-shifting segmented phase coding method is evaluated using simulations and experiments. • This paper establishes theoretical model to demonstrate the feasibility of applying phase-shifting segmented phase coding method. • The phase-shifting segmented phase coding method can effectively eliminate fringe order errors by bidirectional coding complementary phases. • Novel phase-shifting segmented phase coding technology can increase the codewords to realize the high-resolution. The phase-coding method is widely used during 3D measurement for attaining absolute phase retrieval. However, traditional the phase-coding method still suffers from low accuracy and insufficient reliability. To address these issues, a phase-shifting segmented phase coding method was proposed in this work for absolute phase retrieval in complex object measurements, which specifically improved upon the segmented method of phase coding. Coding patterns with different phase-shifting were obtained by embedding the codeword into the phase-shifting phase. These patterns were also combined and arranged to create novel segmented coding patterns. In addition, this segmented encoding can be self-connected based on its different phase-shifting information to obtain the complete fringe order, achieving thus absolute phase retrieval of over 36 codewords. To solve the problem of the periodic misalignment of the wrapped phase and fringe order, the complementary phase coding method was encoded by the bidirectional coding method, and the separation method of the bidirectional coding was improved. From experimental results, it was demonstrated that the proposed method has high measurement accuracy and reliability. [ABSTRACT FROM AUTHOR]

Abstract Salinity gradient energy is a kind of the Gibbs free energy of mixing, and it is a clean, sustainable, and renewable energy source which is projected of the capacity to generate about 2.6 TW of electricity from all rivers flowing into the sea. However, the current technology to convert the salinity gradient energy to electricity suffers from low conversion efficiency, which results in a low output power density. In this work, we develop a new type of the graphene reverse electrodialysis (GRED) device which can efficiently convert the salinity gradient energy into electricity. The GRED device is fabricated based on a simple and straightforward ion irradiation perforation approach, and it is demonstrated to exhibit a record-high energy conversion efficiency of 39% and a record-high output power density of 27 W/m2 at room temperature, manifesting its high promise for the clean energy harvesting from the salinity gradient. Theoretical simulations based on molecular dynamics and continuum theory further show that the charge at the pore edge is of crucial importance for achieving high ion selectivity. In light of this finding, we show that the output power density of GRED can be further boosted to 126 W/m2 if it is operated at a slightly elevated temperature of 47 °C, for which the heating could be from industrial thermal waste in a practical sense. Graphical abstract A new-type graphene reverse electrodialysis (GRED) device is fabricated to convert the salinity gradient energy into electricity, and the GRED device shows a high output power density up to 126 W/m 2 and a high energy conversion efficiency of 39%. fx1 Highlights • A new graphene reverse electrodialysis (GRED) device is fabricated. • The GRED device can convert salinity gradient energy into electricity. • The energy conversion efficiency of GRED can be up to 39%. • The output power density can be 126 W/m2 if it is operated at 47 °C. • The ion selectivity of GRED is investigated by MD and PNP simulations. [ABSTRACT FROM AUTHOR]

Gray code plus phase-shifting method embed the codeword into intensity to reconstruct complex three-dimensional shape. Owing to surface reflectivity and noise, it is less robust for measuring the surfaces of object with low contrast. In order to solve the problem, the codeword is embedded into phase to determine fringe order for obtaining the unwrapped phase. However, measurement speed is limited. Therefore, a fast three-dimensional shape measurement method based on color phase coding is proposed. As it adopts a color sinusoidal fringe to obtain wrapped phase and an additional color phase coding fringe to determine fringe order, the method can achieve fast complex three-dimensional shape measurement with different contrast. Color crosstalk and gamma nonlinearity are compensated to improve the measurement accuracy. The experiment results confirm the effectiveness and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

To solve the problem of the measurement information loss caused by occlusion of the field of view in line-structured light measurement, a vision occlusion solution of the line-structured light measurement system based on a plane mirror is proposed in this work. In the system, a symmetrical structure between real and virtual images was created by the mirror. A checkerboard with a light stripe and its mirror image were captured by the camera in an image. The centers of the light stripe and its mirror image were corrected by the vanishing point constraint, and a calibration method of the free plane target was used to calibrate the real and virtual light planes. The real and virtual point clouds of the object were obtained by scanning with a linear guide. According to the ideal reflection model of the mirror, the real and virtual point clouds of the object were transformed into a common coordinate system, and an iterative closest point (ICP) algorithm was used to realize fine registration. As a result, the occluded parts can be compensated for each other. Compared with a standard ball, the mean/maximum absolute error of the measurement was 0.2553/0.3276 mm. The experimental results revealed that the proposed method can obtain the complete surface of the object, thus effectively solving the occlusion problem in the line-structured light measurement, and reducing the loss of the measurement information, which can meet the industrial measurement requirements. [ABSTRACT FROM AUTHOR]

Binary fringe defocused projection can resolve the problem caused by the nonlinear gamma of the projector. Owing to the intersecting axis measurement system, the broadening of the fringe period on the reference plane can cause measurement errors. Non-uniform periodical binary fringe defocused projection is utilized to overcome this problem. After appropriate defocused projection of non-uniform periodical binary fringe, uniform periodical sinusoidal fringe can be obtained on the reference plane. This method can prevent the nonlinear gamma effect and broadening of the fringe period, and filter high harmonics and high-frequency noise. Three-dimensional (3-D) shape measurement experiments of standard flat are performed with four-step phase-shift method. Experimental results demonstrate that the proposed method exhibits high measurement precision. Highly accurate 3-D measurements of large objects can also be performed with the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: As the blade must have precise size and accurate shape, three-dimensional (3D) profile measurement of the blade is very important. 3D profile measurement method based on multi-value coding is proposed. This method designs a multi-value coding stripe pattern combined with the four-step phase-shifting method. Two kinds of fringe patterns are projected onto the object respectively, one is sinusoidal intensity distribution used for wrapped phase, the other is multi-value coding fringe pattern for phase unwrapping. Because this encoding method is simple, and easy to implement, the absolute phase can be quickly implemented. Experimental results demonstrated that the proposed method can achieve a high precision, high speed and low cost 3D profile measurement of the blade. [Copyright &y& Elsevier]

Abstract: Fringe projection profilometry is widely used for three-dimensional shape measurement. In an oblique-angle projection, the fringe cycle is broadened on the reference plane. Phase errors are mainly caused by the nonlinear gamma of the projector and fringe cycle broadening. This study describes a phase error compensation method to eliminate these phase errors. A look-up table that stores phase errors is constructed for phase error compensation. Based on it, a new height equation is proposed. The experimental results show that the proposed method can compensate for the phase errors of the fringe projection profilometry, thereby improving the measurement accuracy significantly. [Copyright &y& Elsevier]

Abstract: Fringe projection profilometry (FPP) is a widely used three-dimensional profile measurement technique. One vital step in this technique is calibration, which determines the system accuracy. The least-squares method, because of its flexibility and simplicity, is commonly used in system calibration for FPP. However, calibration results are affected by the nonlinear gamma of the projector and projection fringe cycle broadening. This paper proposes a new look-up table (LUT) generation method by analyzing the differences between the real and ideal unwrapped phases. The aforementioned problems could then be solved after the phase error is compensated by the LUT. Finally, the validity of the proposed method is demonstrated through experiments, and the accuracy reaches 0.02mm. [Copyright &y& Elsevier]

Rationale and Objectives: To assess the applicability of a novel macromolecular polyethylene glycol (PEG)-core gadolinium contrast agent for monitoring early antiangiogenic effects of bevacizumab using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). Materials and Methods: Athymic rats (n = 26) implanted with subcutaneous human melanoma xenografts underwent DCE-MRI at 2.0 T using two different macromolecular contrast agents. The PEG core cascade polymer PEG12,000-Gen4-(Gd-DOTA)16, designed for clinical development, was compared to the prototype, animal-only, macromolecular contrast medium (MMCM) albumin-(Gd-DTPA)35. The treatment (n = 13) and control (n = 13) group was imaged at baseline and 24 hours after a single dose of bevacizumab (1 mg) or saline to quantitatively assess the endothelial-surface permeability constant (KPS, μL⋅min⋅100 cm3) and the fractional plasma volume (fPV,%), using a two-compartment kinetic model. Results: Mean KPS values, assessed with PEG12,000-Gen4-(Gd-DOTA)16, declined significantly (P < .05) from 29.5 ± 10 μL⋅min⋅100 cm3 to 10.4 ± 7.8 μL⋅min⋅100 cm3 by 24 hours after a single dose of bevacizumab. In parallel, KPS values quantified using the prototype MMCM albumin-(Gd-DTPA)35 showed an analogous, significant decline (P < .05) in the therapy group. No significant effects were detected on tumor vascularity or on microcirculatory parameters in the control group between the baseline and the follow-up scan at 24 hours. Conclusion: DCE-MRI enhanced with the novel MMCM PEG12,000-Gen4-(Gd-DOTA)16 was able to monitor the effects of bevacizumab on melanoma xenografts within 24 hours of a single application, validated by the prototype, animal-only albumin-(Gd-DTPA)35. PEG12,000-Gen4-(Gd-DOTA)16 may be a promising candidate for further clinical development as a macromolecular blood pool contrast MRI agent. [Copyright &y& Elsevier]

Abstract: As the blade must have precise size and accurate shape, three-dimensional profile measurement of the blade is very important. In this paper, three-dimensional profile measurement method of the blade based on surface structured light is proposed. A new phase unwrapping method is also proposed. This encoding method combined coding fringe pattern with the four-step phase-shifting method, the coding information is embedded into the phase, which can be used to determine fringe order for absolute phase retrieval. The encoding method is simple and easy to implement, so the phase unwrapping of the blade can be quickly perform. The experimental and simulation results show that the method can achieve a high precision, high speed and low cost three-dimensional profile measurement of the blade. [Copyright &y& Elsevier]

Abstract: Phase unwrapping is an important part of the three-dimensional profile measurement. It determines the measurement accuracy of the system. For the phase of the projection gratings on each object or among separated objects are often discontinuous, a modified temporal phase unwrapping algorithm with the exponent of 4 and changing phase-shifting step is proposed. Comparing with the traditional exponential sequence temporal phase unwrapping algorithm with the exponent of 2, the proposed algorithm is simpler. When the same number of fringes is projected, the measurement accuracy using the proposed algorithm is greatly improved. Computer simulations and experiments prove the effectiveness of the method. [Copyright &y& Elsevier]

Abstract: Sinusoidal fringe patterns are popularly used in conventional Fourier transform profilometry. There are numerous harmonics in the Fourier spectrum, so as to avoid spectrum overlapping; the maximum range of measurement is limited. The present paper studies FTP based on properly defocusing a binary square wave. There are only odd harmonics in the Fourier spectrum of a binary square wave, and the maximum range of measurement is expanded 1.5 times. Defocusing has a low-pass filtering effect and higher-order odd harmonics are suppressed. Therefore, the fundamental spectrum is easy to extract. The proposed method overcomes the filtering problem of conventional FTP. Measurement experiments show that the proposed method has a good measurement result and the measurement accuracy is improved. [Copyright &y& Elsevier]

Abstract: The projecting grating method is used to measure the profile of the object. When the object has the steps shape or there are shadows in the grating stripes, the disconnected phase cannot be correctly unwrapped. In order to resolve these problems, the dual-frequency grating is programmed by the computer. And it is projected to the measurement object. The measurement object is placed on the exact rotary platform. After getting two images, the two images are mosaiced, the clear object image modulated by the grating is got. Then a novel Fourier transform profilometry is used to process the image, and the filter is designed to filter the high frequency and the low frequency. The phase difference of high frequency is worked out based on that of the low frequency. At last, the three dimension profile measurement is realized. Comparing with the traditional Fourier transform profile, the method cuts down three times frequency shifting reduces the calculation time and improves filter precision. The result indicates that the method is simple, with high precision. Three dimension profile measurement of the object that has the steps shape or there are shadows in its grating stripes can be successfully resolved. [Copyright &y& Elsevier]

Rationale and Objectives: The objective is to compare three different ultrasmall superparamagnetic iron oxides (USPIOs) for magnetic resonance (MR) imaging of normal bone marrow in rodents.Materials and Methods: Femoral bone marrow in 18 Sprague-Dawley rats was examined by using MR imaging before and up to 2 and 24 hours postinjection (PI) of 200 mumol of Fe/kg of SHU555C (n = 6), ferumoxtran-10 (n = 6), or ferumoxytol (n = 6), using T1-weighted (50 ms/1.7 ms/60 degrees = repetition time [TR]/echo time [TE]/flip angle) and T2*-weighted (100 ms/15 ms/38 degrees = TR/TE/flip angle) three-dimensional spoiled gradient recalled echo sequences. USPIO-induced bone marrow was evaluated qualitatively and quantified as signal-to-noise ratio (SNR) and change in signal intensity (DeltaSI) values. A mixed-effect model was fitted to the SNR and DeltaSI values, and differences among USPIOs were tested for significance by using F tests.Results: At 2 hours PI, all three USPIOs showed marked positive signal enhancement on T1-weighted images and a corresponding marked signal loss on T2*-weighted images. At 24 hours PI, the T1 effect of all three USPIOs disappeared, whereas T2*-weighted images showed persistent signal loss on SHU555C and ferumoxytol-enhanced MR images, but not ferumoxtran-10-enhanced MR images. Corresponding SNR and DeltaSI values on T2*-weighted MR images at 24 hours PI were significantly different from baseline for SHU555C and ferumoxytol, but not ferumoxtran-10.Conclusion: All three USPIO contrast agents, ferumoxtran-10, ferumoxytol, and SHU555C, can be applied for MR imaging of bone marrow. Ferumoxtran-10 apparently reveals a different kinetic behavior in bone marrow than ferumoxytol and SHU555C. [ABSTRACT FROM AUTHOR]

• A high dynamic range real-time 3D measurement is proposed. • The proposed method can measure the dynamic objects with shiny surfaces. • Three images with different intensities are separated from one color image. • Compared with the other methods, the proposed method requires fewer images. The high dynamic range (HDR) fringe projection technique is widely used to measure the three-dimensional (3D) shapes of objects with shiny surfaces; however, it tends to compromise when measuring the dynamic objects. To reduce the number of images and improve the real-time performance, a Fourier transform profilometry (FTP)-based method that can increase the dynamic range for real-time 3D measurement is proposed. Firstly, single-color patterns are projected onto the measured object, and one captured color image can be separated into three monochrome images with different intensities by taking advantage of the different responses of R, G, and B channels. Second, the HDR fringe pattern is generated by compositing three monochrome images, and then processed by the background-normalized algorithm to obtain the final fringe pattern. Subsequently, FTP is employed to retrieve the phase map and obtain the 3D shape. The experimental results demonstrated that the proposed method can measure the dynamic objects with shiny surfaces in real-time 3D measurement system. [ABSTRACT FROM AUTHOR]

• The influence of the parameters of the spherical and aspheric MLAs on the luminance efficiencywe were investigated. High fill factor parabola curve MLAs was introduced to improve the light out-coupling efficiency of OLED. • Geometric ray tracing was employed to investigate and optimize the tructure parameters of spherical and aspheric MLAs, such as the curved profile, the base shape, the fill factor, the aspect ratio (the ratio of height to diameter), and the material refractive index of the MLAs. • The experimental results are consistent with the trend of the simulation results, and show that the maximum light out-coupling efficiency of OLED improvement is 49 %. Aspheric microlens arrays (MLAs) are introduced on glass substrate to improve the light out-coupling efficiency (LOCE) of organic light-emitting diode (OLED). Geometric ray tracing was employed to simulate the improved effects and optimize the structure parameters of the MLAs pattern. The simulation results show that when the parameters of MLAs as follows, the curved profile is parabola, the base shape is hexagon, the fill factor is 1, the aspect ratio is 0.6, and the material refractive index should be match to that of the substrate of the OLED, which can improve LOCE maximum. Poly-dimethyl-siloxane (PDMS) parabola curve MLAs films ware fabricated by maskless lithography technique and template replication. The experimental results show that the MLAs can improve the LOCE and the trends of the experimental results agree with the simulation results. A maximum increase of 49 % in the coupling efficiency was achieved. [ABSTRACT FROM AUTHOR]

• A novel adaptive projection fringe pattern technique is proposed. • The proposed method is capable of measuring the small objects with shiny surface. • Fringe pattern with low intensity is projected onto the bright region to avoid the pixel saturation. • A new algorithm to generate the adaptive fringe patterns is proposed. • Compared with the existing methods, the proposed method needs fewer patterns. Fringe projection techniques have been widely used in three-dimensional (3D) small-field measurement; however, measuring the 3D shapes of small objects with high ranges of reflectivity across their surfaces remains challenging because image saturation leads to measurement error. In this study, a novel adaptive fringe projection technique was proposed to address this issue. First, a 255 uniform gray-level pattern was projected onto the surface to mark the saturated region in the captured image. Second, another uniform gray-level pattern with lower intensity was used to calculate the reflectivity across the surface and an appropriate projection gray level in the camera coordinate system was calculated at the pixel level. Third, a set of orthogonal sinusoidal fringe patterns were projected onto the object to establish the spatial relationship between the camera and projection systems, and adaptive fringe patterns were generated in the projection coordinate system. Subsequently, the generated adaptive fringe patterns were used to measure the object. The experimental results demonstrate that the proposed method could retrieve the 3D shapes of small shiny objects with high accuracy and relatively few images. [ABSTRACT FROM AUTHOR]

The calibration of the system's geometric parameters is always an important step in 3D topography measurement based on fringe projection profilometry. However, the traditional calibration method needs to be realized by the implementation of an electric guide rail, which exhibits certain problems, such as complicated operation and inconvenient carrying. Along these lines, in this work, a new simple and flexible calibration method is introduced. For the proposed method, a round calibration board only needs to be moved arbitrarily many times within the depth of field of the camera and projector. By using the existing camera calibration method, each calibration plate position and pose can be derived, while the phase of every pixel and the height data, as well as the phase of every pixel-height mapping relationship, were established. In addition, the rational function fitting method was used to accurately estimate the phase distribution of the black area of the calibration plate, avoiding thus the influence of the phase artifacts caused by high-contrast calibration targets. The minimum root mean square error (RMSE) of the experimental results was 0.074 mm. Compared with the traditional method, our approach is more flexible and convenient, and has no loss of reliability. [ABSTRACT FROM AUTHOR]

Design and synthesis of highly active, inexpensive and durable catalyst for simultaneous hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is highly desired for green hydrogen generation. In this work, high conductivity NiTe nanorods are coupled with amorphous CoFe layered double hydroxide (LDH) to achieve a hierarchical NiTe@CoFe LDH heterostructure via a hydrothermal reaction and a subsequent electrodeposition process. The as-prepared three-dimensional (3D) self-supported NiTe@CoFe LDH nanorods endow highly efficient electron transfer and mass diffusion, and this architecture with abundant electrode/electrolyte interfaces can provide more active sites. Consequently, with the synergistic effect of NiTe and CoFe LDH, the as-prepared NiTe@CoFe LDH electrocatalyst achieved a current density of 10 mA cm−2 with low overpotentials of 218 mV and 103 mV for OER and HER, respectively, and showing a robust stability for 50 h. Furthermore, an alkaline electrolyzer with NiTe@CoFe LDH serving as both the anode and cathode requires a cell voltage of 1.56 V to yield 10 mA cm−2 current density, and can sustain for more than 50 h, with a slightly current density increase of 5%, showing potential for practical industrial application to generate hydrogen. This work highlights the construction low cost highly efficient 3D rods electrode for promising applications in green hydrogen generation. • Novel hierarchical NiTe@CoFe LDH heterostructure electrocatalyst are fabricated. • 3D structure benefits electrolyte diffusion and gas releasing. • Prepared catalyst only require 262 mV and 103 mV to drive 100 mA cm−2 for OER and 10 mA cm−2 for HER, respectively. • NiTe@CoFe LDH delivers a cell voltage of 1.56 V for overall water splitting. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To correlate dynamic MRI assays of macromolecular endothelial permeability with microscopic area–density measurements of vascular endothelial growth factor (VEGF) in tumors. Methods and material: This study compared tumor xenografts from two different human cancer cell lines, MDA-MB-231 tumors (n =5), and MDA-MB-435 (n =8), reported to express respectively higher and lower levels of VEGF. Dynamic MRI was enhanced by a prototype macromolecular contrast medium (MMCM), albumin-(Gd-DTPA)35. Quantitative estimates of tumor microvascular permeability (K PS; μl/min×100cm3), obtained using a two-compartment kinetic model, were correlated with immunohistochemical measurements of VEGF in each tumor. Results: Mean K PS was 2.4 times greater in MDA-MB-231 tumors (K PS =58±30.9μl/min×100cm3) than in MDA-MB-435 tumors (K PS =24±8.4μl/min×100cm3) (p <0.05). Correspondingly, the area–density of VEGF in MDA-MB-231 tumors was 2.6 times greater (27.3±2.2%, p <0.05) than in MDA-MB-435 cancers (10.5±0.5%, p <0.05). Considering all tumors without regard to cell type, a significant positive correlation (r =0.67, p <0.05) was observed between MRI-estimated endothelial permeability and VEGF immunoreactivity. Conclusion: Correlation of MRI assays of endothelial permeability to a MMCM and VEGF immunoreactivity of tumors support the hypothesis that VEGF is a major contributor to increased macromolecular permeability in cancers. When applied clinically, the MMCM-enhanced MRI approach could help to optimize the appropriate application of VEGF-inhibiting therapy on an individual patient basis. [Copyright &y& Elsevier]

Abstract: We present a method of chaos and its control in semiconductor laser based on sliding tunable dual-wedges. We numerically reveal the dynamics of chaos and its control in semiconductor lasers by changing the length of sliding tuneable dual-wedges. The results indicated that, with the appropriate changes of the length of sliding tuneable dual-wedge, the laser can be controlled into steady state, single-periodic, multi-periodic and even chaos respectively. The results also provide a new method to generate various period states in the chaos system. [Copyright &y& Elsevier]

Highlights • A segmented quantization phase coding and decoding method is proposed. • A new phase unwrapping algorithm based on segmented quantization phase coding is proposed. • The proposed method can guarantee high measurement accuracy in high-frequency. • The proposed method allows the measurement of both single object and isolated objects with complicated shape because of using segmented quantization phase coding method. • The proposed method only needs six patterns to obtain absolute phase, the model has advantages for high-speed measurement applications. Abstract Codeword is very important in phase unwrapping based on phase coding method. Each phase coding fringe is marked with a unique codeword and then used to determine the fringe order for absolute phase retrieval. However, the traditional phase coding method is limited by the number of codeword. To overcome this problem, a segmented quantization phase coding and decoding method is proposed to achieve absolute phase retrieval without reducing the difference between adjacent quantized phase values or increasing the quantization levels. The quantized phase is modulated by a specific coding sequence and then embedded into phase coding fringe patterns, thereby greatly improving the accuracy of the decoding. The coding creates multiple segments of the whole region and each segment embeds the special coding sequence. Through the corresponding decoding algorithm, the fringe order can be obtained, and following this, the absolute phase is obtained. Simulation and experimental results demonstrate the feasibility and superiority of the proposed method to measure both a single object and multiple isolated objects. [ABSTRACT FROM AUTHOR]

Hydrogen is an efficient energy carrier alternative to the non-renewable traditional fossil fuels energy. Water electrolysis is a promising technique used for clean hydrogen generation. Usually, the oxygen-evolution reaction (OER) and urea-oxidation reaction (UOR) processes play a vital role in hydrogen production and pollution control. Herein, we report the fabrication of a three-dimensional (3D) crystalline/amorphous heterostructure NiTe/Ni-S electrocatalyst grown on nickel-foam (NF) via facile two steps (i.e. , hydrothermal and electrodeposition) strategy. The synthesized NiTe/Ni-S catalyst exhibits an excellent performance toward the OER with a small overpotential of 216 mV to achieve 10 mA cm−2 current density in 1.0 M KOH. Further, it only requires a small voltage of 1.315 V (vs. the reversible-hydrogen-electrode (RHE)) to drive 10 mA cm−2 current density for UOR in 1 M KOH with 0.33 M urea, and reveals excellent long-term catalytic stability. Moreover, the overall water splitting experiments were conducted in 1 M KOH electrolyte with the NiTe/Ni-S catalyst as an anode and Pt/C as a cathode. It is obvious that only 1.500 and 1.527 V is required to achieve a current densities of 10 mA cm−2 and 20 mA cm−2, respectively. [Display omitted] • Novel crystalline/amorphous heterostructure NiTe/Ni-S electrocatalyst are fabricated. • Rod like structure benefits electrolyte diffusion and gas releasing and Ni-S films supply massive accessible catalytic sites. • NiTe/Ni-S need an overpotential of 216 mV at 10 mA cm−2 for OER and a potential of 1.31 V for UOR. [ABSTRACT FROM AUTHOR]

• A single conical microresonator (CMR) is fabricated by combining arc discharge and pull method. • We report a tunable EIT-like effect in a CMR coupled by a tapered fiber waveguide theoretically and experimentally. By axially changing the coupled point, we observe dynamic Fano and EIT-like lineshape. • Fano and EIT-like effect with a quality (Q) factor are achieved by scanning the varied diameter carefully originating from approximate two resonant frequencies in a wavelength apart. In addition, these experimental observations can be well fitted with the coupled mode theory. In this study, we experimentally and theoretically demonstrate electromagnetically induced transparency (EIT)-like in a single conical microresonator (CMR) fabricated by combining arc discharge and pull method. Benefited from the gradually changing diameter along the longitudinal axis of the CMR, the resonance frequency can be tuned when the CMR coupled by a tapered fiber waveguide. The characteristic of internally-tuning in our CMR is confirmed theoretically, numerically and experimentally. In particular, Fano and EIT-like effect with a quality (Q) factor are achieved by scanning the varied diameter carefully originating from approximate two resonant frequencies in a wavelength apart. In addition, these experimental observations can be well fitted with the coupled mode theory. These findings may open new avenues for realizing high- Q EIT, which pave the way for an enhanced approach in bio-sensing applications, nonlinear optics and optical switching devices. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The purpose of the study was to evaluate the efficacy of imatinib mesylate in the treatment of nephrogenic systemic fibrosis (NSF) in a rat model administered high-dose gadodiamide, erythropoietin (Epo) and intravenous iron (IV iron). Materials and methods: The local committee for animal research approved this study. Four groups of six Hannover–Wistar rats were studied. Group A received normal saline; Group B, IV iron and Epo; Group C, gadodiamide, IV iron and Epo; and Group D, gadodiamide, IV iron, Epo and imatinib. Gadodiamide was administered at 10 mmol/kg of body weight for 5 consecutive days. Imatinib was administered at 50 mg/kg starting 3 days before gadodiamide injections and was continued for 50 days afterwards. Biopsies were taken 3 and 7 weeks after gadodiamide injection, and dermal histology was analyzed as well as gadolinium deposition as measured by inductively coupled plasma mass spectrometry. Additionally, rats treated with gadodiamide were observed for a total of 16 weeks. For comparison of cellularity, a linear mixed-effects model was used, and for metal deposition, an analysis of variance was used, which was corrected with a Tamhane correction for unequal variances. Results: Rats treated with gadodiamide in addition to IV iron and Epo (group C) had worse skin lesions on histology (P<.001) compared to control animals (groups A and B). Treatment with imatinib resulted in decreased cellularity (group D vs C, P<.001), although there was no difference in the amount of deposited gadolinium (P>.5). Histology at 16 weeks demonstrated increased fibrosis and dermal calcifications, consistent with the clinical presentation of NSF. Conclusions: The administration of imatinib to rats treated with high-dose gadodiamide resulted in decreased lesion severity. [Copyright &y& Elsevier]

Abstract: Objective: To evaluate the feasibility of dual-energy CT (DECT) for monitoring dynamic changes in the renal corticomedullary sodium gradient in swine. Material and methods: This study was approved by our Institutional Animal Care and Use Committee. Four water-restricted pigs were CT-scanned at 80 and 140kVp at baseline and at 5min intervals for 30min during saline or furosemide diuresis. The renal cortical and medullary CT numbers were recorded. A DECT basis material decomposition method was used to quantify renal cortical and medullary sodium concentrations and medulla-to-cortex sodium ratios at each time point based on the measured CT numbers. The sodium concentrations and medulla-to-cortex sodium ratios were compared between baseline and at 30min diuresis using paired Student t-tests. The medulla-to-cortex sodium ratios were considered to reflect the corticomedullary sodium gradient. Results: At baseline prior to saline diuresis, the mean medullary and cortical sodium concentrations were 103.8±8.7 and 65.3±1.7mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.59. At 30min of saline diuresis, the medullary and cortical sodium concentrations decreased to 72.3±1.0 and 56.0±1.4mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.29 (P <0.05). At baseline prior to furosemide diuresis, the mean medullary and cortical sodium concentrations were 110.5±3.6 and 66.7±4.1mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.66. At 30min of furosemide diuresis, the medullary and cortical sodium concentrations decreased to 68.5±0.3 and 58.9±4.0mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.16 (P <0.05). One of the 4 pigs developed acute tubular necrosis likely related to prolonged hypoxia during intubation prior to the furosemide diuresis experiment. The medulla-to-cortex sodium ratio for this pig, which was excluded from the mean medulla-to-cortex ratio above, was 1.07 at baseline and 1.15 at 30min following the administration of furosemide. Conclusion: DECT monitoring of dynamic changes in the renal corticomedullary sodium gradient after physiologic challenges is feasible in swine. [Copyright &y& Elsevier]

Abstract: Purpose: To examine the clinical significance of persistent renal enhancement after iodixanol administration. Methods: We retrospectively studied 166 consecutive patients who underwent non-enhanced abdominopelvic CT within 7days after receiving intra-arterial (n =99) or intravenous (n =67) iodixanol. Renal attenuation was measured for each non-enhanced CT scan. Persistent renal enhancement was defined as CT attenuation >55Hounsfield units (HU). Contrast-induced nephropathy (CIN) was defined as a rise in serum creatinine >0.5mg/dL within 5days after contrast administration. Results: While the intensity and frequency of persistent renal enhancement was higher after intra-arterial (mean CT attenuation of 73.7HU, seen in 54 of 99 patients, or 55%) than intravenous contrast material administration (51.8HU, seen in 21 of 67, or 31%, p <0.005), a multivariate regression model showed that the independent predictors of persistent renal enhancement were a shorter time interval until the subsequent non-enhanced CT (p <0.001); higher contrast dose (p <0.001); higher baseline serum creatinine (p <0.01); and older age (p <0.05). The route of contrast administration was not a predictor of persistent renal enhancement in this model. Contrast-induced nephropathy was noted in 9 patients who received intra-arterial (9%) versus 3 who received intravenous iodixanol (4%), and was more common in patients with persistent renal enhancement (p <0.01). Conclusion: Persistent renal enhancement at follow-up non-contrast CT suggests a greater risk for contrast-induced nephropathy, but the increased frequency of striking renal enhancement in patients who received intra-arterial rather than intravenous contrast material also reflects the larger doses of contrast and shorter time to subsequent follow-up CT scanning for such patients. [Copyright &y& Elsevier]

There is increasing resistance to carbapenems among Klebsiella pneumoniae ,and fluoroquinolones (FQ) are increasingly used to treat infections from extended-spectrum β- lactamase(ESBLs) and carbapenemase-producing Klebsiella pneumoniae. However, the acquisition of plasmid-mediated quinolone resistance (PMQR) or the spontaneous mutation of the quinolone resistance-determining regions (QRDR) of the gyrA and parC genes can severely affect the therapeutic effect of quinolones. The goal of this study was to investigate the molecular determinants of FQ resistance(FQ-R) in carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates from Heilongjiang Province,China. We isolated 40 strains of CRKP from a treatment center in the eastern part of Heilongjiang Province from January 2016 to December 2018. The VITEK2 Compact analyzer was used to identify and detect drug sensitivity. Different types of drug resistance genes were detected by polymerase chain reaction (PCR). PCR and DNA sequencing were used to assess the presence of qnrA, qnrB, qnrS,qepA and acc(6′) Ib-cr genes,which are plasmid-encode genes that can contribute to resistance. The sequences of gyrA and parC genes were sequenced and compared with the sequences of standard strains to determine if mutations were present.Multi-site sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were performed on the strains to assess homology. The isolated CRKP strains showed rates of resistance to fluoroquinolones of 22.5% to 42.5%. The resistance rate of ciprofloxacin was significantly higher than that of levofloxacin.Nine CRKP strains (22.5%) showed co-resistance to ciprofloxacin and levofloxacin.The quinolone resistant strains were screened for plasmid-encoded genes that can contribute to resistance (PMQR genes).Among the 17 quinolone resistant strains,one strain contained no PMQR genes,twelve strains contained two PMQR genes,and four strains contained four PMQR genes. Acc (6′) Ib-cr was the most frequently detected PMQR gene, detected in 95% of strains tested (38 of 40) and in 94.1% of the quinolone-resistant strains (16 of 17). The qepA gene encoding an efflux pump was not detected in any strains.No isolate carried five different PMQRs simultaneously.Changes of S83I and D87G changes in gyrA , and the S80I change in parC ,which were mediated by QRDR,were identified in two isolates,which showed resistance to both ciprofloxacin and levofloxacin.Most of the FQ-R strains(58.8%,10/17) belong to ST(sequence type) 76, which is dominant in the local area, while all the mutant strains (100%,2/2),that differ in at least one site from standard bacteria, belong to the ST11 group. The strains were isolated from a hospital where there had been a recent outbreak of ST76 type CRKP in the neurosurgery ward and intensive care unit. CRKP strains were identified that were insensitive or even resistant to quinolones,and this resistance is common in Heilongjiang Province of eastern China;fluoroquinolone-resistance in these clinical CRKP strains is a complex interplay between PMQR determinants and mutations in gyrA and parC.The resistance level caused by QRDR mutation is higher than that caused by PMQR, however, the high frequency of PMQR genes in the isolated CRKP strains suggests the potential for impact of these genes.PMQR determinants are often found in carbapenemase-producing or ESBLs-producing Klebsiella pneumoniae ,and some resistance genes,such as: SHV , TEM , CTX-M-15 ,and OXA-1 are closely associated with FQ-R. Finally, geographical factors can affect the emergence and spread of PMQR and QRDR.Some genetic lineages have higher potential risks, and continuous close monitoring is required. • For Klebsiella pneumoniae , chromosome-mediated quinolone resistance is stronger than plasmid-mediated. • Quinolone resistance often occurs in ESBL-producers, and there is a certain correlation between them. • Geographical factors have a certain impact on the emergence and spread of quinolone-resistance. [ABSTRACT FROM AUTHOR]

• A new approach named S-shaped segmental phase encoding is proposed. • The method can expand the range of code words by a segmentation mechanism. • The fringe order judgment accuracy can be guaranteed by Gray code. • Experimental results demonstrated the high accuracy of our method. Phase-based encoding has good immunity and robustness due to its insensitivity to ambient light, camera noise, and surface reflectance of measured objects. However, the number of code words is limited using traditional phase encoding method. In order to solve this problem, this paper proposes a new approach named S-shaped segmental phase encoding for 3D measurement. Specifically, by using a segmentation mechanism, the proposed method can, firstly, expand the range of code words whose number is limited using traditional phase encoding method. Secondly, the measurement accuracy can be improved. In this paper, Gray code is used to encode the phase encoding segment number, such that the fringe order judgment accuracy can be guaranteed. The experimental results demonstrated more accurate and efficient 3D shape measurement than the traditional methods, especially regarding the measurement of complex and isolated objects. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To assess the effect of positive enteric contrast administration on automatic exposure control (AEC) CT radiation exposure in (1) a CT phantom, and (2) a retrospective review of patients. Materials and methods: We scanned a CT phantom containing simulated bowel that was sequentially filled with water and positive enteric contrast, and recorded the mean volume CT dose index (CTDIvol). We also identified 17 patients who had undergone 2 technically comparable CT scans of the abdomen and pelvis, one with positive enteric contrast and the other with oral water. Paired Student''s t-tests were used to compare the mean CTDIvol between scans performed with and without positive enteric contrast. Both the phantom and patient CT scans were performed using AEC with a fixed noise index. Results: The mean CTDIvol for the phantom with simulated bowel containing water and positive enteric contrast were 8.2±0.2mGy, and 8.7±0.1mGy (6.1% higher than water, p =0.02), respectively. The mean CTDIvol for patients scanned with oral water and with positive enteric contrast were 11.8mGy and 13.1mGy, respectively (p =0.003). This corresponded to a mean CTDIvol which was 11.0% higher (range: 0.0–20.7% higher) in scans with positive enteric contrast than those with oral water in patients. Conclusions: When automatic exposure control is utilized for abdominopelvic CT, the radiation exposure, as measured by CTDIvol, is higher for scans performed with positive enteric contrast than those with oral water. [Copyright &y& Elsevier]