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Summary This paper considers multiuser downlink transmission and detection in a multiple input‐multiple output (MIMO) visible light communication (VLC) system. We combine two promising techniques: space‐shift keying (SSK) and optical orthogonal codes (OOCs). Multiuser downlink transmission is realized by allowing each activated LED to transmit user‐specific OOC simultaneously. An OOC despreader is implemented at the front end of each user terminal (UT) to extract the desired signal and mitigate multiuser interference (MUI). The second part of UT receiver aims to extract the index of the corresponding active LED based on maximum likelihood (ML) or zero‐forcing (ZF) algorithm. The figure of merit we used to access the performance of the proposed downlink multiuser SSK system is the average symbol error rate (SER). Comprehensive Monte Carlo simulations have been undertaken for different system setup to evaluate SER at UT receiver. It is demonstrated that for a specified SER, the required SNR for ML‐based detection algorithm is 3 dB less than the ZF detector in the MUI‐free scenario. On the other hand, the ZF detector outperforms ML detector in the case with residual MUI and limited channel state information (CSI). Both algorithms are computationally attractive, hence can be put into practice in multiuser VLC MIMO system. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to explore the regulatory function of COL1A1 against the apoptosis of embryonic stem cells (ESCs) and the potential function in congenital talipes equinovarus (CTEV). Methods: Muscle tissues were collected from 20 children with CTEV and 20 children without CTEV, followed by detecting the expression of COL1A1 using the RT‐PCR method. COL1A1 was knocked down in H1 and H9 human ESCs using the RNA interference technology, followed by determining the level of COL1A1, PITX1, TBX4, HOXD10, Fas, FasL, and Bax using the Western blotting assay. Results: COL1A1 was found markedly upregulated in muscle tissues of CTEV children. In H1 and H9 human ESCs, compared to the empty vector, COL1A1, PITX1, TBX4, HOXD10, Fas, FasL, and Bax were found notably downregulated after transfected with the siRNA targeting COL1A1. Conclusion: COL1A1 induced the apoptosis of ESCs by mediating the PITX1/TBX4 signaling and might be a potential target for treating CTEV. [ABSTRACT FROM AUTHOR]

Mountain‐cultivated ginseng is typically harvested after 10 years, while ginseng aged over 15 years is considered wild ginseng. This study aims to differentiate mountain‐cultivated ginseng by age, as the fraudulent practice of selling low‐aged cultivated ginseng disguised as high‐aged one is damaging the market. In this study, LC‐MS analyzed 98 ginseng samples, and multivariate statistical analysis identified patterns between samples to select influential components. Machine learning models were developed to identify ginseng samples of different ages. The untargeted metabolomic analysis clearly divided samples aged 4‐20 years into three age groups. Twenty‐two potential age‐dependent biomarkers were discovered to differentiate the three sample groups. Three machine learning models were used to predict new samples, and the optimal model was selected. Some biomarkers could determine age phases according to the differentiation of mountain‐cultivated ginseng samples. These biomarkers were thoroughly analyzed for variation trends. The machine learning models established using the screened biomarkers successfully predicted the age group of new samples. [ABSTRACT FROM AUTHOR]

Panax ginseng, a slow‐growing perennial herb, is the most praised and popular traditional medicinal herb. Mountain‐cultivated ginseng (MCG) and cultivated ginseng (CG) both belong to Panax ginseng C. A. Meyer. The market price and medical effects of this popular health product are closely related to its age. It is widely acknowledged that CG is typically harvested after 4–6 years of growth, but MCG is often collected after 10 years. Until now, the age identification of MCG or mountain wild ginseng (MWG) has remained a major challenge. In this study, we established a novel and rapid method for staining xylem vessels with phloroglucinol and identifying the "annual growth rings" of ginseng by utilizing a stereoscope, which serves as a reliable indicator of the age of MCG. Statistical analysis of the ring radius and the ring density of MCG aged from 1 to 20 years shows that the secondary xylem of MCG increases rapidly in the first 3 years but then gradually slows down from 4 to 10 years, and minor fluctuation is observed in the next 10 years. Meanwhile, the space between the growth rings (ring density) becomes increasingly small with age. This straightforward staining approach can reveal the age of MCG with remarkable clarity and can distinguish MCG from CG. Research Highlights: A novel rapid staining method for Panax ginseng was established.The age of mountain‐cultivated ginseng (MCG) can be identified by microscopic techniques.MCG and cultivated ginseng (CG) can be discriminated by microstructure characteristics. [ABSTRACT FROM AUTHOR]

Dinutuximab (ch14.18) was the first approved monoclonal antibody against the tumor‐associated antigen disialoganglioside GD2. Despite its success in treating neuroblastoma (NB), it triggers a significant amount of neuropathic pain in patients, possibly through complement‐dependent cytotoxicity (CDC). We hypothesized that modifying ch14.18 using antibody engineering techniques, such as humanization, affinity maturation, and Fc engineering, may enable the development of next‐generation GD2‐specific antibodies with reduced neuropathic pain and enhanced antitumor activity. In this study we developed the H3‐16 IgG1m4 antibody from ch14.18 IgG1. H3‐16 IgG1m4 exhibited enhanced binding activity to GD2 molecules and GD2‐positive cell lines as revealed by ELISA, and its cross‐binding activity to other gangliosides was not altered. The CDC activity of H3‐16 IgG1m4 was decreased, and the antibody‐dependent cellular cytotoxicity (ADCC) activity was enhanced. The pain response after H3‐16 IgG1m4 antibody administration was also reduced, as demonstrated using the von Frey test in Sprague–Dawley (SD) rats. In summary, H3‐16 IgG1m4 may have potential as a monoclonal antibody with reduced side effects. [ABSTRACT FROM AUTHOR]

The Qilian–Haiyuan fault zone in the northeastern Tibetan Plateau has been the source of strong earthquakes in the region. In its middle segment, the Jinqianghe fault is an important active fault within the Tianzhu seismic gap; however, little is known about its slip behavior. To present a new horizontal displacement distribution along this fault, we used WorldView‐2 stereo pairs and unmanned aerial vehicle‐based photogrammetry to construct digital elevation models to obtain a detailed tectono‐geomorphic interpretation and geomorphic offsets. The offset marker measurements yielded 135 geomorphic displacements and 8 offset clusters. Radiocarbon dating was used to establish the regional age sequence of the geomorphic units in offset fluvial terraces at four study sites. The displacements and ages linked the offset clusters with the geomorphic unit sequence; the Holocene strike‐slip rate of the Jinqianghe fault was estimated to 4.8–5.6 mm/a at ∼4–12 ka and 2.9–4.7 mm/a from ∼4 ka. Three recent earthquakes (with a recurrence interval of ∼1000 years) represent an active seismic period, revealing the potential seismic hazard along this fault because it has not ruptured in the last 1500 years. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries involve a reversible conversion reaction between sulfur and lithium sulfide (Li2S) via a series of soluble lithium polysulfide intermediates (LiPSs), enabling a high theoretical specific capacity of 1675 mAh g–1. However, this process exhibits large polarization and low sulfur utilization and suffers critical capacity fade. The primary approach to tackle the problem has so far been to infiltrate sulfur into nanostructured carbon. However, most studies using porous carbon as host materials have tested with high electrolyte to sulfur ratios (E/S) (generally > 15 µL mg−1) that compromise the cell‐level energy density. Here, a flower‐shaped porous carbon structure with nickel nanoparticles that can address the problems discussed above is designed. First, the 3D flower‐shaped carbon structure enables short ionic transport lengths. Second, the small pore diameters <10 nm and high specific surface areas > 3300 m2 g−1 with sufficient pore volume are ideal for charging performance for low E/S ratios. Finally, Ni nanoparticles are employed onto the flower‐shaped network to improve the reaction kinetics. Collectively, it is successfully demonstrated that the batteries with a high mass loading of 5 mg cm−2 and a 5 µL mg−1 E/S ratio can retain cycle retention of 70% after 150 cycles. [ABSTRACT FROM AUTHOR]

Porphyrinic metal–organic frameworks (PMOFs) are very appealing electrocatalytic materials, in part, due to their highly porous backbone, well‐defined and dispersed metal active sites, and their long‐range order. Herein a series of (Co)PCN222 (PCN: porous coordination network) (nano)particles with different sizes are successfully prepared by coordination modulation synthesis. These particles exhibit stability in 0.1 m HClO4 electrolyte with no obvious particle size or compositional changes observed after being soaked for 3 days in the electrolyte or during electrocatalysis. This long‐term stability enables the in‐depth investigation into the electrocatalytic oxygen reduction, and it is further demonstrated that the (Co)PCN222 particle size correlates with its catalytic activity. Of the three particle sizes evaluated (characteristic length scales of 200, 500, and 1000 nm), the smallest size demonstrates the highest mass activity while the largest size has the highest surface area normalized activity. Together these results highlight the importance of determining the structural stability of framework catalysts and provide insights into the important roles of particle size, opening new avenues to investigate and improve the electrocatalytic performance of this class of framework material. [ABSTRACT FROM AUTHOR]

The Qilian Shan, located in the northeastern Tibet, is under strong tectonic activity and earthquake motion due to the propagation of the plateau. At the mountain front of the eastern Qilian Shan, the Tongziba River, in the southern Zhangye Basin, flows northward and successively cuts the Minle‐Damaying Fault and the Yonggu Anticline, two parallel structures within the Frontal Thrust system of the Qilian Shan. Here we present a detailed record of seven strath terraces of this river that documents the history of active deformation of the two structures. Based on the estimated crustal shortening distance from the deformed terraces and the terrace formation age constrained by AMS 14C and optically stimulated luminescence (OSL) dating, a horizontal slip rate of 1.4 ± 0.5 mm/year of the Minle‐Damaying Fault is constrained since 16.7 ± 1.8 kyr, and a shortening rate of 1.3 ± 0.4 mm/year across the Yonggu Anticline has been estimated in a similar time frame, respectively. In total, the shortening rate across the mountain front is estimated to be 2.7 ± 0.6 mm/year. GPS data show a similar modern shortening rate in this area, which indicates the rate of crustal shortening may be comparable in the modern and 104‐year scales. Our study supports a higher crustal shortening rate along the mountain front of the eastern Qilian Shan than that of the western Qilian Shan since the Late Quaternary. Key Points: The Minle‐Damaying Fault and the Yonggu Anticline have been active since at least 16.7 ± 1.8 kyrEstimated Late Quaternary shortening rate across the eastern Qilian Shan foreland is 2.7 ± 0.6 mm/year from terraces analysisCrustal shortening rate along the mountain front of the eastern Qilian Shan is probably higher than that of the western Qilian Shan [ABSTRACT FROM AUTHOR]

High‐resolution topographic data sets have now become increasingly available, which allows for remotely measuring and analyzing offset features and their associated slip distributions at a very high resolution along a fault, hence providing important insights into the fault behavior. The West Helanshan Fault is a Holocene active right‐lateral strike‐slip fault located at the junction of the Tibetan Plateau, Alashan, and Ordos blocks. In this study, a 2‐m‐resolution DEM of the West Helanshan Fault was built from the WorldView‐3 stereo satellite images (0.5 m). Combined with the high‐resolution topography acquired from the Unmanned Aerial Vehicle (UAV) images based on the Structure from Motion (SfM) method, a total of 180 lateral offsets and 201 vertical displacements were acquired along ~50 km of the fault. By statistical analysis of the offset observations and constructing the cumulative slip profiles, we conclude that large paleoearthquakes have produced characteristic slip accumulation along the fault with a right‐lateral slip of ~3 m and a vertical slip of ~1 m, rupturing at least two segments of the fault simultaneously, which corresponds to a moment magnitude of Mw 7.1 ~ 7.5. The cumulative slip profiles suggest that the fault has likely propagated northward over its lifetime, and the south segment may be the most mature section of the fault where larger coseismic slip of earthquake ruptures may occur. The ratio of lateral to vertical displacement has remained constant (~3:1) through multiple successive events, indicating that the fault has maintained the same kinematic style over the last few thousands of years. Key Points: Large paleoearthquakes have produced characteristic slip along the fault with a lateral slip of ~3 m and a vertical slip of ~1 mThe fault has propagated northward over its lifetime, and larger coseismic slip of earthquakes may occur on the south segment of the faultThe fault has maintained the same kinematic style with a constant ratio of lateral to vertical displacement [ABSTRACT FROM AUTHOR]

Ni,N‐doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2R) to CO; this activity has often been attributed to the presence of nitrogen‐coordinated, single Ni atom active sites. However, experimentally confirming Ni−N bonding and correlating CO2 reduction (CO2R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile‐derived Ni,N‐doped carbon electrocatalysts (Ni‐PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X‐ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square‐planar geometry that strongly resembles the active sites of molecular metal–porphyrin catalysts. [ABSTRACT FROM AUTHOR]

Background: Cryopreservation in dimethyl sulfoxide and storage at -80 °C extends the shelf life of platelets to at least 2 years, allowing greater availability in rural and military areas. While cryopreserved platelets (CPPs) have been extensively characterized for coagulation and thrombin generation, reports on the mechanism of adverse reactions to CPPs transfusion are scarce. Here, we tested the hypothesis that CPPs facilitate phagocytosis by Kupffer cells and subsequently promote the inflammatory response in Kupffer cells.Study Design and Methods: P-selectin expression, glycoprotein Ibα clustering and phosphatidylserine (PS) surface exposure on platelets stored at 22 °C, 4 °C and - 80 °C for 3 days were examined by flow cytometry. The phagocytosis of mepacrine-labeled platelets coincubated with THP-1 cells was examined by flow cytometry and confocal microscopy, and the release of cytokines from THP-1 cells was measured by enzyme-linked immunosorbent assay.Results: CPPs showed a marked enhancement of exposed PS but dramatically reduced glycoprotein Ibα expression and clustering compared with platelets stored at 4 °C. Activation of THP-1 cells was stronger by CPPs than by platelets stored at 22 °C and 4 °C. CPP interference tests using annexin V and anti-P-selectin showed that CPPs induced increases in PS- and P-selectin-mediated phagocytosis, as well as secretion of the proinflammatory cytokine tumor necrosis factor-α, and interleukins IL-1β and IL-6, but a decrease in transforming growth factor-β production in THP-1 cells. Surface-exposed PS was more effective than P-selectin for the activation of THP-1 cells.Conclusion: CPPs triggered PS and P-selectin-mediated phagocytosis by macrophages and stimulated the inflammatory response of macrophages. [ABSTRACT FROM AUTHOR]

The northwest striking Qishan‐Mazhao fault (QMF) accommodates complex deformation in the Tibet‐Ordos transition zone. We studied the geologic and geomorphic expression of the QMF using interpretations of high‐resolution satellite images and structure‐from‐motion models combined with detailed field investigations. Displaced loess tablelands, stream channels, and fluvial terraces show that the QMF is predominately a left‐lateral strike‐slip fault with a minor normal component. The magnetic susceptibility and optically stimulated luminescence ages of offset fluvial terraces yield left‐lateral slip rates ranging from 0.5 to 1.0 mm/year. Regionally, the QMF and the Haiyuan fault (HYF) form a large right step, in which the Liupanshan Mountains are located. The QMF shares a similar orientation and sense of motion to the HYF, suggesting that the left‐lateral slip of the HYF is not completely absorbed as crustal shortening across the Liupanshan Mountains but is partially transferred to slip along the QMF. Key Points: The northwest striking QMF is a left‐lateral fault with a minor oblique normal componentLeft‐lateral slip of the HYF is partially transferred by slip (~0.5–1.0 mm/year) along the QMFTectonic deformation on the southwestern Ordos is strongly controlled by the northeastward expansion of the Tibetan Plateau [ABSTRACT FROM AUTHOR]

Abstract: 3‐Hydroxy‐2‐oxindoles are valuable biologically active molecules, and efficient methods for their synthesis under mild condition are highly sought after. Here we report a base‐ and metal‐free C(sp3)−H hydroxylation of 2‐oxindoles promoted by commercially available inexpensive TEMPO and atmospheric air as a hydroxylation reagent at room temperature. This protocol provides a mild and simple strategy for the construction of C−O bonds in moderate to good yields with wide functional group tolerance. [ABSTRACT FROM AUTHOR]

Obesity is a complex health issue and it can cause many health and social problems. Previous studies reported that lipase is a main target for obesity treatment. We synthesized R- exo-2-norbornyl- N- n-butylcarbamate and S- exo-2-norbornyl- N- n-butylcarbamate as potential pseudomonas lipase inhibitors to probe the enantioselectivity of the enzyme and demonstrated that R- exo-2-norbornyl- N- n-butylcarbamate had better enzyme enantioselectivity, ki and the docking model with Pseudomonas species lipase in our previous studies. In this article, we reported the property of the Pseudomonas species lipase inhibitors, R-and S- endo-2-norbornyl- N- n-butylcarbamate and compared the docking models of these two compounds with R- and S- exo-2-norbornyl- N- n-butylcarbamates by AutoDock. We found that S- endo-2-norbornyl- N- n-butylcarbamate has the best enantioselectivity, ki and docking model and this study could provide useful information about enzyme enantioselectivity for the development of Pseudomonas species lipase inhibitors for obesity treatment. [ABSTRACT FROM AUTHOR]

Polymer-based materials with high electrical conductivity are of considerable interest because of their wide range of applications. The construction of a 3D, compactly interconnected graphene network can offer a huge increase in the electrical conductivity of polymer composites. However, it is still a great challenge to achieve desirable 3D architectures in the polymer matrix. Here, highly conductive polymer nanocomposites with 3D compactly interconnected graphene networks are obtained using a self-assembly process. Polystyrene (PS) and ethylene vinyl acetate (EVA) are used as polymer matrixes. The obtained PS composite film with 4.8 vol% graphene shows a high electrical conductivity of 1083.3 S/m, which is superior to that of the graphene composite prepared by a solvent mixing method. The electrical conductivity of the composites is closely related to the compact contact between graphene sheets in the 3D structures and the high reduction level of graphene sheets. The obtained EVA composite films with the 3D graphene structure not only show high electrical conductivity but also exhibit high flexibility. Importantly, the method to fabricate 3D graphene structures in polymer matrix is facile, green, low-cost, and scalable, providing a universal route for the rational design and engineering of highly conductive polymer composites. [ABSTRACT FROM AUTHOR]

Biphenyl-4-acyoxylate-4′- N-butylcarbamates 1-8 are synthesized from 4,4′-biphenol and are characterized as the pseudosubstrate inhibitors of acetylcholinesterase. In other words, the inhibitors bind to the enzyme and react with the enzyme to form the tetrahedral intermediates for the Ki steps, and then the tetrahedral intermediates exclude the leaving groups to form a common N-butycarbamyl enzyme intermediate for the kc steps. Due to a linear character of the 4,4′-biphenyl moiety, the 4′- N-butylcarbamate moieties of the inhibitors react with the Ser200 residue of the enzyme while the 4-acyoxylate moieties of the inhibitors, on the other hand, should fit in the peripheral anionic site of the enzyme, which is located at the mouth of the deep active site gorge. Thus, carbamates with varied acyl substituents at the 4-position of the biphenyl ring are good candidates for probing the quantitative structure activity relationships for the peripheral anionic site of the enzyme. The fact that the p Ki, log kc, and log Ki values are correlated with neither the Taft substituent constant (σ*) nor the Taft steric constant ( Es) indicates that the 4-acyoxylate moieties of the inhibitors are too far away from the reaction center. However, the p Ki, log kc, and log Ki values are linearly correlated with the Hansch hydrophobicity constant, π. The intensity constants (ψ) for these correlations are 0.16, −0.035, and 0.13, respectively. These results indicate that interactions between the 4-acyoxylate groups of the inhibitors and the peripheral anionic site of the enzyme are mainly hydrophobic ones. The correlation results are slightly improved by using the two-parameter correlations with the Taft substituent steric constant, Es, and π. For p Ki, log kc, and log Ki- Es-π correlations, the ψ values are 0.21, −0.021, and 0.19, respectively; the intensity constants for steric effect (δ) are 0.08, 0.022, and 0.10, respectively. Besides hydrophobic interactions, the two-parameter correlations also suggest that little steric hindrance occurs for the bulkier inhibitors to pass by the peripheral anionic site of the enzyme. © 2005 Wiley Periodicals, Inc. J Biochem Mol Toxicol 19:234-243, 2005; Published online in Wiley InterScience (). DOI 10.1002/jbt.20087 [ABSTRACT FROM AUTHOR]