The paper establishes a measurement-launch station correlation model of a single-frequency off-line radar system, derives the principles of the three-dimensional TOA positioning method and the ...two-dimensional TOA positioning method to estimate the target height, and gives the analysis of the GDOP positioning accuracy of the corresponding algorithm, and Through the simulation verification of a three-transmission single-receiving external radiation source positioning model, the effects of different algorithms on positioning accuracy and measurement-transmission station correlation are analysed. The results show that using the two-dimensional TOA positioning method to estimate the target height can improve the measurement-transmitting station correlation probability of the single-frequency off-line radiation source radar.
MicroRNA-21 is an oncogenic miRNA that modulates the expression of multiple cancer-related target genes. We conducted this meta-analysis to assess diagnostic role of circulating miR-21 in CRC, hoping ...to choose the best biomarker in CRC diagnosis.
We searched the PubMed, CNKI and WanFang database to identify records related to diagnostic role of circulating miR-21 in CRC. The search words were "microRNA-21", "miRNA-21", "colorectal cancer", "colorectal carcinoma" and "diagnosis". The searched articles were published before 14
th
July 2020.
We got 18 studies to conduct this meta-analysis including 1129 blood specimens of CRC patients and 951 control specimens. The meta-analysis showed that the pooled sensitivity and specificity of circulating miR-21 for CRC diagnosis were 77% (95% CI, 70-82) and 83% (95% CI, 78-88). The combined positive likelihood ratio (PLR) was 4.20 (95% CI, 3.12-5.66) and the combined negative likelihood ratio(NLR) was 0.30 (95% CI, 0.23-0.38). The diagnostic odds ratio (DOR) was 16.48 (95% CI 10.09-26.91) and the area under the summary receiver operating characteristic curve (SROC) for the included studies was 0.87(95%CI, 0.84-0.90).
Our meta-analysis results suggest that circulating miR-21 has a potential diagnostic value with moderate sensitivity and good specificity for CRC.
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•Two new copper compounds 1 and 2 containing flexible 3, 5, 6-Htcpa ligands have been synthesized and characterized.•1 is a doubly mononuclear cocrystal and 2 is an oxalato-bridged ...binuclear structure.•Magnetic measurements indicated both weak antiferromagnetic coupling behavior in 1 and 2.•2 can be obtained with 1 as one of the starting marerials associated with greatly conformational variation.
Two new copper compounds, namely Cu(3,5,6-tcpa)2(H2O)4·Cu(3,5,6-tcpa)2(H2O)2 (1) and Cu2(3,5,6-tcpa)2(2,2′-bipy)2(oxa)·2EtOH (2) (3,5,6-Htcpa = 2-((3,5,6-trichloro pyridin-2-yl)oxy)acetic acid, 2,2′-bipy = 2,2′-bipyridine, oxa = oxalate dianion), have been synthesized by solvothermal method and systematically characterized. Single-crystal X-ray diffraction analysis show that 1 is an interesting double mononuclear cocrystal and consists of two discrete and stereochemically different complexes: one octahedral, the other tetrahedral about the copper centres. While for 2, two equivalent copper ions are in square pyramidal geometry and linked by oxalate anion forming a novel binuclear cluster. The OH···O hydrogen bonds, Cl···Cl halogen bonds and/or π···π stacking interactions play an important part in construction of the 3D networks for 1 and 2. The magnetic measurements indicate that there is weak antiferromagnetic coupling between two copper ions in 1 and 2. Notably, compound 2 also can be obtained in a higher yield with 1 as one of the starting material and the driving force for this transition process have been carefully discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Numerous studies have determined that physical cues, especially the nanotopography of materials, play key roles in directing stem cell differentiation. However, most research on nanoarrays for stem ...cell fate regulation is based on nonbiodegradable materials, such as silicon wafers, TiO2, and poly(methyl methacrylate), which are rarely used as tissue engineering biomaterials. In this study, we prepared biodegradable polylactic acid (PLA) nanopillar arrays with different diameters but the same center-to-center distance using a series of anodic aluminum oxide nanowell arrays as templates. Human adipose-derived stem cells (hADSCs) were selected to investigate the effect of the diameter of PLA nanopillar arrays on stem cell differentiation. By culturing hADSCs without the assistance of any growth factors or osteogenic-induced media, the differentiation tendencies of hADSCs on the nanopillar arrays were assessed at the gene and protein levels. The assessment results suggested that the osteogenic differentiation of hADSCs can be driven by nanopillar arrays, especially by nanopillar arrays with a diameter of 200 nm. Moreover, an in vivo animal model of the samples demonstrated that PLA film with the 200 nm pillar array exhibits an improved ectopic osteogenic ability compared with the planar PLA film after 4 weeks of ectopic implantation. This study has provided a new variable to investigate in the interaction between stem cells and nanoarray structures, which will guide the bone regeneration clinical research field. This work paves the way for the utility of degradable biopolymer nanoarrays with specific geometrical and mechanical signals in biomedical applications, such as patches and strips for spine fusion, bone crack repair, and restoration of tooth enamel.
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IJS, KILJ, NUK, PNG, UL, UM
Organic single crystals manifest the intrinsic physical properties of materials. However, traditional growth of organic single crystals is limited by low solubility from solutions or complexity from ...physical vapor deposition. Here we report a new method to grow organic single crystals by microspacing in-air sublimation, which avoids costly vacuum system and time-consuming procedures and is practical for a wide range of organic crystals. In situ crystal growth observation revealed an unprecedented vapor-to-melt-to-crystal mechanism, resulting from the micrometer scale spacing distance between the source and the growth position. FET devices based on the rubrene crystals directly grown on Si/SiO2 substrate exhibited higher mobility than the best record using SiO2 as the gate dielectric. This effective organic crystal growth technique can be affordable and handled for almost every lab, which may be beneficial for future research and application of organic crystals.
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Layout-level gate or routing camouflaging techniques have attracted interest as countermeasures against reverse engineering of combinational logic. In order to minimize area overhead, typically only ...a subset of gate or routing components are camouflaged, and each camouflaged component layout can implement one of a few different functions or connections. The security of camouflaging relies on the difficulty of learning the overall combinational logic function without knowing the functions implemented by the individual camouflaged components of the circuit. In this paper, we expand our previous work on using incremental SAT solving to reconstruct the logical function of a circuit with camouflaged components. Our algorithm uses the standard attacker model in which an adversary knows only the noncamouflaged component functions, and has the ability to query the circuit to learn the correct output vector for any input vector. Our results demonstrate a 10.5× speedup in average runtime over the best known existing deobfuscation algorithm prior to this technique. The results presented go beyond our previous work by showing that this technique, previously applied only to a particular style of gate camouflaging, is general and can be used to deobfuscate three different proposed styles of camouflaging. We give results to quantify the effectiveness of camouflaging techniques on a variety of ISCAS-85 benchmark circuits.
In order to search for multifunctional epoxy thermosets (EP) with low flammability, high transparency and satisfied mechanical performance, DOPO‐based phosphonate ammonium salt (DOA) was synthesized ...from 10‐hydroxy‐9,10‐dihydro‐9‐oza‐10‐phosphaphenanthrene‐10‐oxide (DOPO‐OH) and 2‐amino‐2‐methyl‐1,3‐propanediol (AMPD). Under the influence of DOA, the flame‐retardant and mechanical performances of the resulting EP were obviously improved. On account of the enhanced interaction and the incorporated flexible fragments in epoxy macromolecular chains, the tensile strength, elongation at break, and impact toughness of EP/5.0 wt% DOA significantly increased from 65.4 ± 1.2 MPa, 6.7 ± 0.6%, and 12.1 ± 1.3 kJ m−2 of EP to 81.4 ± 2.8 MPa, 10.6 ± 0.5%, and 18.0 ± 1.1 kJ m−2, respectively. In the presence of DOA, the limiting oxygen index (LOI) value of EP/5.0 wt% DOA increased to 35.5% and it passed the underwriter laboratories‐94 vertical burning tests (UL‐94 V) and got a V‐1 rating. Moreover, the peak value of heat release rate (PHRR) was decreased by 38.0%. The analyses of char residues and volatile products showed that the activities of DOA on reducing the flammability of EP were ascribed to the protective effect of the char, the release of incombustible gases, and the radical‐capture action of phosphorus‐containing free radicals. Moreover, the modified epoxy thermosets still retained a high transparency.
DOPO‐based phosphonate ammonium salt modified epoxy thermosets exhibit excellent flame retardancy, strengthened mechanical properties and high transparency. Meanwhile, the relevant mechanisms are also disclosed through comprehensive studies. Generally, the as‐obtained epoxy thermosets would fulfill the needs of diversified material functions in the future.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A new double-stranded chain manganese complex has been synthesized and structurally characterized, in which 3, 5, 6-tcpa− ligand adopts a new coordination mode of bidentate bridging-μ2. Magnetic ...studies reveal that it exhibits antiferromagnetic coupling behavior.
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•A new double-stranded chain manganese 1 complex containing 3, 5, 6-Htcpa was described.•The 3, 5, 6-tcpa− ligand adopts a new coordination mode of bidentate bridging-μ2 in 1.•The crystal packing of 1 contain π⋯π stacking and Cl⋯Cl halogen bonds interactions.•The magnetic properties for 1 have been discussed.
A new coordination polymer Mn(3, 5, 6-tcpa)2(2, 2′-bipy)n (1) has been synthesized by the hydrothermal reaction of manganese sulfate hydrate with 3, 5, 6-trichloropyridine-2-oxyacetic acid (3, 5, 6-Htcpa) and 2, 2′-bipyridine (2, 2′-bipy) coligands. The X-ray single-crystal diffraction analysis shows that the MnII center is in deformed octahedral geometry bonded by two pyridyl nitrogen atoms of 2, 2′-bipy molecule and four carboxy oxygen atoms of four different 3, 5, 6-tcpa− ligands. The 3, 5, 6-tcpa− anions play as bidentate bridging-μ2 linkers and connect neighbouring MnII ions together to form the 1D double-stranded chain structure of 1, which displays interesting chair form Mn2(COO)2 eight-membered rings. 1 is further assembled into 3D network by the co-effects of π⋯π stacking and Cl⋯Cl halogen bonds interactions. In addition, the magnetic characterizations indicated weak antiferromagnetic coupling between MnII centers for 1.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As the key part of a steel-concrete composite bridge, the mechanical properties shear connectors that have direct impacts on the bearing capacity of the whole bridge. Angle connectors and ...twin-perfobond rib (T-PBL) connectors are commonly used in long-span steel-concrete composite bridges. Considering the convenience of construction, a new type of shear connector, the channel connector, is proposed. Push-out tests on three groups of 12 shear connector specimens under monotonic and repeated loads were carried out, and the static and fatigue behavior of the three different shear connectors were compared and analyzed. The results show that the ultimate bearing capacity of channel connectors is the largest, while that for the angle connectors is the second largest and that for T-PBL connectors is the smallest. With the increase in cyclic loading times, the ratio of residual deformation to plastic deformation shows a significant upward trend. The deformation recovery ability of the specimens decreases gradually, and the stiffness deteriorates continuously. The stiffness degradation of channel connectors is the slowest, and the stiffness degradation of angle connectors and T-PBL connectors is faster. The energy dissipation of T-PBL connectors is the largest, while the energy dissipation of angle and channel connectors is the same. The channel connectors proposed in this paper can be used as good shear connectors in steel-concrete composite bridges because of their strength improvement and their certain energy dissipation capacity. In addition, the 3D non-linear finite element models based on the three kinds of shear connectors is established to simulate the whole loading process by using the general finite element software ABAQUS. The results of finite element analysis are in good agreement with the experimental results, which can be used as a powerful supplement to the experimental research.
•A new type of shear connector for a steel-concrete composite girder bridge, the channel connector, is proposed.•Push-out tests on three type shear connectors under monotonic and repeated loads were carried out.•The initial stiffness of specimens under repeated loading is not significant compared with monotonic loading.•The channel connectors are suitable for a steel-concrete composite girder because of their good mechanical properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Federated learning (FL) is a distributed deep learning method which enables multiple participants, such as mobile phones and IoT devices, to contribute a neural network model while their private ...training data remains in local devices. This distributed approach is promising in the edge computing system where have a large corpus of decentralized data and require high privacy. However, unlike the common training dataset, the data distribution of the edge computing system is imbalanced which will introduce biases in the model training and cause a decrease in accuracy of federated learning applications. In this paper, we demonstrate that the imbalanced distributed training data will cause accuracy degradation in FL. To counter this problem, we build a self-balancing federated learning framework call Astraea, which alleviates the imbalances by 1) Global data distribution based data augmentation, and 2) Mediator based multi-client rescheduling. The proposed framework relieves global imbalance by runtime data augmentation, and for averaging the local imbalance, it creates the mediator to reschedule the training of clients based on Kullback-Leibler divergence (KLD) of their data distribution. Compared with FedAvg, the state-of-the-art FL algorithm, Astraea shows +5.59% and +5.89% improvement of top-1 accuracy on the imbalanced EMNIST and imbalanced CINIC-10 datasets, respectively. Meanwhile, the communication traffic of Astraea can be 92% lower than that of FedAvg.
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