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Objective Coronavirus disease 2019 (COVID-19) is a major challenge facing the world. Certain guidelines issued by National Health Commission of the People's Repubilic of China recommend intravenous immunoglobulin (IVIG) for adjuvant treatment of COVID-19. However, there is a lack of clinical evidence to support the use of IVIG. Methods This single-center retrospective cohort study included all adult patients with laboratory-confirmed severe COVID-19 in the Respiratory and Critical Care Unit of Dabie Mountain Regional Medical Center, China. Patient information, including demographic data, laboratory indicators, the use of glucocorticoids and IVIG, hospital mortality, the application of mechanical ventilation, and the length of hospital stay was collected. The primary outcome was the composite end point, including death and the use of mechanical ventilation. The secondary outcome was the length of hospital stay. Results Of the 285 patients with confirmed COVID-19, 113 severely ill patients were included in this study. Compared to the non-IVIG group, more patients in the IVIG group reached the composite end point [12 (25.5%) vs 5 (7.6%), P = 0.008] and had longer hospital stay periods [23.0 (19.0–31.0) vs 16.0 (13.8–22.0), P P = 0.167), however, patients in the IVIG group had longer hospital stay periods (P = 0.041). Conclusion Adjuvant therapy with IVIG did not improve in-hospital mortality rates or the need for mechanical ventilation in severe COVID-19 patients. Our study does not support the use of immunoglobulin in patients with severe COVID-19 patients.

Triphenylimidazole-based ampholytes with intramolecular charge transfer were designed with the introduction of carboxyl groups. In solution, the synergistic solvent and ionization effects on the ampholytes led to a unique pendulum-type fluorescence variation during the water content increasing process. Among them, 4-(4,5-bis(4-hydroxyphenyl)-1H-imidazol-2-yl)benzoic acid showed the most prominent three-step fluorescence switching property.

In this study, two new metal-organic frameworks, namely, {(H2NMe2)[Zn3LiO(BTA)2](DMF)3}n (1, H3BTA=3,3′,3″-[1,3,5-benzenetriyltris(carbonylimino)] trisbenzoic acid) and {(Me2NH2)2[In2(TTA)2(FBA)2](DMF)3}n (2, H3TTA=4,4′-(((5-((4-(hydroxy-l2-methoxy)phenoxy) methyl)-2,4,6-trimethyl-1,3-phenylene)bis(methylene))bis(oxy))dibenzoic acid, HFBA=2-fluorobenzoic acid), were obtained via a one-pot solvothermal reaction of metal salts and organic connectors. The structures of the title two metal-organic coordination compounds were structurally probed via X-ray single crystal diffraction technique. In connection to their structures, the MTT assay was used to access the in vitro antitumor activities for compounds 1 and 2 against the human lung cancer cells (MSTO-211H, NCI-H1299 and NCI-H292).

Background Heme oxygenase-1 (HO-1) is an inducible defense gene which plays a significant role in inflammation. HO-1 protects cells and tissues through the mechanism of anti-oxidation, maintaining microcirculation and anti-inflammation. The aim of the current study is to investigate the role of HO-1 on systemic inflammatory response in severe acute pancreatitis (SAP). Methods Forty male Sprague-Dawley (SD) rats were randomly assigned into four groups: control group (n = 10); SAP group (n = 10), SAP model was induced by retrograde injection of 3% sodium taurocholate through pancreatic duct; HO-1 stimulation group (n = 10), SD rats were injected 75 μg/kg hemin intraperitoneally 30 min after induction of SAP; HO-1 inhibition group (n = 10), SD rats were injected 20 μg/kg Zinc porphyrin (Zn-PP) intraperitoneally 30 min after induction of SAP. After 24 h of SAP establishment, tissues were collected for HO-1, tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) mRNA expression, and blood samples were collected for cytokines and biochemical measurements. Meanwhile, the histopathological changes of pancreas and liver tissues were observed. Results The expression of HO-1 mRNA and protein were significantly induced by SAP in rat pancreas and liver. Hemin treatment significantly decreased oxidative stress and TNF-α in plasma and tissues, while the IL-10 was significantly increased. Pancreas and liver injury induced by SAP was markedly attenuated by Hemin treatment. Moreover, inhibition of HO-1 expression by Zn-PP administration aggravated the injury caused by SAP. Conclusions Induction of HO-1 in early SAP may modulate systemic inflammatory response and prevent pancreas and nearby organs such as liver injury through inhibition of TNF-α and augmentation of IL-10.

To explore the mechanism of Shenmai injection (SMI) on severe acute pancreatitis (SAP) through heme oxygenase-1 (HO-1) signaling.A total of 40 male Sprague-Dawley (SD) rats (220-260 g) were grouped into the following four categories (n = 10): SAP + SMI + Zinc protoporphyrin (ZnPP), SAP + SMI, SAP, and sham surgery groups. ZnPP is a specific inhibitor of HO-1. Four percent of sodium taurocholate (1 mL/kg) was retrogradely injected via the pancreatic duct to induce the SAP model. The SAP group rats received 1.6 mL/kg saline by intravenous injection 30 min after the induction of SAP. The SAP + SMI group rats received 1.6 mL/kg SMI by intravenous injection 30 min after the induction of SAP. The SAP + SMI + ZnPP group rats received an intravenous injection of 1.6 mL/kg SMI and intraperitoneal administration of 30 mg/kg ZnPP 30 min after the SAP induction. Twenty-four hours after the SAP induction, blood samples were collected for the measurement of amylase, lipase, creatinine, myeloperoxidase, interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and HO-1 level, while tissue specimens were harvested for the determination of HO-1, TNF-α, and IL-10 mRNA level. Meanwhile, histopathological changes in organs (pancreas, lung, and kidney) were stored.The serum concentration of amylase, lipase, creatinine, and myeloperoxidase was higher in the SAP group than in the SAP + SMI group. Treatment with SMI increased HO-1 and IL-10 level and reduced TNF-α level in serum and tissues compared to the SAP group (P 0.05). Treatment with SMI abolished the organ-damaging effects of SAP (P 0.05). Furthermore, suppression of HO-1 expression by ZnPP canceled the aforementioned effects.SMI confers protection against the SAP-induced systemic inflammatory response and multiple organs damage via HO-1 upregulation.

Effects of AlN addition on the microstructure and mechanical properties of as-cast Mg-Al-Zn magnesium alloy were investigated using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile testing. Five different samples were made with different amounts of AlN(0wt%, 0.12wt%, 0.30wt%, 0.48wt%, 0. 60wt%). The results show that the phases of as-cast alloy are composed of α-Mg,β-Mg17Al12. The addition of AlN suppressed the precipitation of the β-phase. And, with the increase of AlN content, the microstructure of β-phase was changed from the reticulum to fine grains. When AlN content was up to 0.48wt% in the alloy, the β-phase became most uniform distribution. After adding 0.3wt% AlN to Al-Mg-Zn alloy, the average alloy grain size reduced from 102μm to 35μm ,the tensile strength of alloy was the highest. The average tensile strength increased from 139MPa to 169.91MPa, the hardness increased from 77.7HB to 98.4HB, but the elongation changes indistinctively. However, when more amount of AlN was added, the average alloy grain size did not reduce sequentially and increased to 50μm by adding 0.6wt% AlN and the β-phase became a little more. Keywords: Al-Mg-Zn alloy; AlN; β-Mg17Al12; Tensile strength

Much research has been done since the concept of ecosystem services was put forward. However, activities have concentrated on the larger (global or national) scale, and fragile agroecosystems disturbed by human activity, such as that of the Loess Plateau where decay of the ecological environment occurs through severe soil erosion and harsh natural conditions, have scarcely been considered. Using various parameters such as market value, shadow price and opportunity cost, the authors have calculated the value of agricultural ecosystem services in Ansai county in the Loess region, to include conserving soil (Es) and water (Ew), fixing CO2 and releasing O2 (Ea), maintaining nutrient cycling (En) and decontaminating the environment (Ee). The results show that the gross value of services from the ecosystem is Yuan31,699 million, which is 170 times the production value (Ep). This implies that even this fragile ecosystem has an important support function, although it has been disregarded for a long time. In Ansai county, the agro-ecosystem provides great ecological support for economic productivity. The value of the various contributions to ecological services is, for En, Yuan (RMB)28,481 million (89.8%), for Ew, RMB1,391 million (4.4%), for Ea, RMB1,325 million (4.2%) for Vp, RMB185 million (0.6%), for Es, RMB258 million (0.8%) and for Ee, RMB57 million (0.2%). Moreover, the results show that there is an imbalance between ecological productivity and economic productivity in this area, which is a general problem across the entire Loess Plateau. The first priority for restoring the ecological environment is to extend the areas of grassland and forest in order to improve conservation of soil and water.

A color-tunable novel-look-up-table (CT-NLUT) for fast one-step calculation of full-color computer-generated holograms is proposed. The proposed method is composed of four principal fringe patterns (PFPs) such as a baseline, a depth-compensating and two color-compensating PFPs. CGH patterns for one color are calculated by combined use of baseline-PFP and depth-compensating-PFP and from them, those for two other colors are generated by being multiplied by the corresponding color-compensating-PFPs. color-compensating-PFPs compensate for differences in the wavelength between two colors based on their unique achromatic thin-lens properties, enabling transformation of one-color CGH pattern into those for other colors. This color-conversion property of the proposed method enables simultaneous generation of full color-CGH patterns, resulting in a significant reduction of the full color-CGH calculation time. Experimental results with test scenario show that the full color-CGH calculation time of the proposed CT-NLUT has been reduced by 45.10%, compared to the conventional NLUT. It has been further reduced by 96.01% when a data compression algorithm, called temporal redundancy-based NLUT, was used together, which means 25-fold reduction of its full color-CGH calculation time. Successful computational and optical reconstructions of full color-CGH patterns confirm the feasibility of the proposed method.

A new approach for fast generation of computer-generated-holograms (CGHs) by combined use of the N-LUT method and block matching motion compensation technique is proposed. Here, we apply block matching-based motion compensation algorithm to N-LUT-based CGH generation method by which a higher similarity between adjacent frames can be obtained. In the proposed method, the input video images are divided into blocks of fixed size and the CGHs of every block in reference frames are pre-calculated with the N-LUT method. The motion vectors of every block in the reference frame are extracted between reference frame and current frame, and a compensated frame image can be obtained by shifting every block’s position according to the motion vectors. Through this process, 3-D objects data to be calculated for its video holograms are dramatically reduced leading to the greater reduction of the calculation time compared with the conventional temporal redundancy-based N-LUT (TR-N-LUT) method. The experiments have found that the average number of calculated object points for one frame and the average calculation time for one object point of the proposed method are reduced by 30.05% and 21.23% respectively compared to those with the conventional TRNLUT method.

A new three-directional motion compensation-based novel-look-up-table (3DMC-NLUT) based on its shift-invariance and thin-lens properties, is proposed for video hologram generation of three-dimensional (3-D) objects moving with large depth variations in space. The input 3-D video frames are grouped into a set of eight in sequence, where the first and remaining seven frames in each set become the reference frame (RF) and general frames (GFs), respectively. Hence, each 3-D video frame is segmented into a set of depth-sliced object images (DOIs). Then x, y, and z-directional motion vectors are estimated from blocks and DOIs between the RF and each of the GFs, respectively. With these motion vectors, object motions in space are compensated. Then, only the difference images between the 3-directionally motion-compensated RF and each of the GFs are applied to the NLUT for hologram calculation. Experimental results reveal that the average number of calculated object points and the average calculation time of the proposed method have been reduced compared to those of the conventional NLUT, TR-NLUT and MPEG-NLUT by 38.14%, 69.48%, and 67.41% and 35.30%, 66.39%, and 64.46%, respectively. (C) 2014 Optical Society of America

A new robust MPEG-based novel look-up table (MPEG-NLUT) is proposed for accelerated computation of video holograms of fast-moving three-dimensional (3-D) objects in space. Here, the input 3-D video frames are sequentially grouped into sets of four, in which the first and remaining three frames in each set become the reference (RF) and general frames (GFs). Then, the frame images are divided into blocks, from which motion vectors are estimated between the RF and each of the GFs, and with these estimated motion vectors, object motions in all blocks are compensated. Subsequently, only the difference images between the motion-compensated RF and each of the GFs are applied to the NLUT for CGH calculation based on its unique property of shift-invariance. Experiments with three types of test 3-D video scenarios confirm that the average number of calculated object points and the average calculation time of the proposed method, have found to be reduced down to 27.34%, 55.46%, 45.70% and 19.88%, 44.98%, 30.72%, respectively compared to those of the conventional NLUT, temporal redundancy-based NLUT (TR-NLUT) and motion compensation-based NLUT (MC-NLUT) methods. (C) 2014 Optical Society of America

Thus far, various approaches to generate the computer-generated holograms (CGHs) of 3-D objects have been suggested but, most of them have been applied to the still images, not to the video images due to their computational complexity. Recently, a method to fast compute the CGH patterns of 3-D video images has been proposed by combined use of data compression and novel look-up table (N-LUT) techniques. In this method, temporally redundant data of 3-D video images are removed with the differential pulse code modulation (DPCM) algorithm and then the CGH patterns for these compressed video images are calculated with the N-LUT method. However, as the 3-D objects move rapidly, image differences between the video frames may increase, which results in a massive growth of calculation time of the video holograms. Therefore, we propose a novel approach to significantly reduce the computation time of 3-D video holograms by employing a new concept of motion-vector of the 3-D object. In the proposed method, 3-D objects are firstly segmented from the 1st frame of the 3-D videos, and the CGH patterns for each segmented object are computed with the N-LUT algorithm. Secondly, motion vectors between each segmented object and the corresponding objects in the consecutive 3-D video frames are calculated. Thirdly, the CGH patterns for each segmented object are shifted with the calculated motion vectors. Finally, all these shifted CGH patterns are added up to generate the hologram patterns of the consecutive 3-D video frames. To confirm the feasibility of the proposed method, experiments are performed and the results are comparatively discussed with the conventional methods in terms of the number of object points and computation time.

A novel approach for fast generation of video holograms of three-dimensional (3-D) moving objects using a motion compensation-based novel-look-up-table (MC-N-LUT) method is proposed. Motion compensation has been widely employed in compression of conventional 2-D video data because of its ability to exploit high temporal correlation between successive video frames. Here, this concept of motion-compensation is firstly applied to the N-LUT based on its inherent property of shift-invariance. That is, motion vectors of 3-D moving objects are extracted between the two consecutive video frames, and with them motions of the 3-D objects at each frame are compensated. Then, through this process, 3-D object data to be calculated for its video holograms are massively reduced, which results in a dramatic increase of the computational speed of the proposed method. Experimental results with three kinds of 3-D video scenarios reveal that the average number of calculated object points and the average calculation time for one object point of the proposed method, have found to be reduced down to 86.95%, 86.53% and 34.99%, 32.30%, respectively compared to those of the conventional N-LUT and temporal redundancy-based N-LUT (TR-N-LUT) methods. (C) 2013 Optical Society of America

We propose a new approach for optical refocusing of three-dimensional (3-D) objects on their real depth without a pickup-range limitation based on subdivided-elemental image arrays (sub-EIAs) and local periodic δ-function arrays (L-PDFAs). The captured EIA from the 3-D objects locating out of the pickup-range, is divided into a number of sub-EIAs depending on the object distance from the lens array. Then, by convolving these sub-EIAs with each L-PDFA whose spatial period corresponds to the specific object's depth, as well as whose size is matched to that of the sub-EIA, arrays of spatially-filtered sub-EIAs (SF-sub-EIAs) for each object depth can be uniquely extracted. From these arrays of SF-sub-EIAs, 3-D objects can be optically reconstructed to be refocused on their real depth. Operational principle of the proposed method is analyzed based on ray-optics. In addition, to confirm the feasibility of the proposed method in the practical application, experiments with test objects are carried out and the results are comparatively discussed with those of the conventional method.

We propose a new type of integral imaging-based large-scale full-color three-dimensional (3-D) display of holographic data based on direct ray-optical conversion of holographic data into elemental images (EIs). In the proposed system, a 3-D scene is modeled as a collection of depth-sliced object images (DOIs), and three-color hologram patterns for that scene are generated by interfering each color DOI with a reference beam, and summing them all based on Fresnel convolution integrals. From these hologram patterns, full-color DOIs are reconstructed, and converted into EIs using a ray mapping-based direct pickup process. These EIs are then optically reconstructed to be a full-color 3-D scene with perspectives on the depth-priority integral imaging (DPII)-based 3-D display system employing a large-scale LCD panel. Experiments with a test video confirm the feasibility of the proposed system in the practical application fields of large-scale holographic 3-D displays. (C)2016 Optical Society of America