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The influence of hydrogen charging potentials on the hydrogen embrittlement susceptibility of R6 ultra-high strength mooring chain steel was investigated via constant potential hydrogen charging slow strain rate tensile tests combined with thermal desorption analysis. The results reveal that hydrogen charging leads to a 38.94% decrease in elongation, while the impact on tensile strength is relatively minor. Furthermore, the specimens experienced intergranular cracking at the critical potential of −1150 mV, with the size of the brittle region increasing as the negative charging potential becomes more negative. And, hydrogen atoms can cause local embrittlement of materials and increase KAM value. [ABSTRACT FROM AUTHOR]

This paper presents a monolithically integrated aptasensor composed of a piezoresistive microcantilever array and an on-chip signal processing circuit. Twelve microcantilevers, each of them embedded with a piezoresistor, form three sensors in a Wheatstone bridge configuration. The on-chip signal processing circuit consists of a multiplexer, a chopper instrumentation amplifier, a low-pass filter, a sigma-delta analog-to-digital converter, and a serial peripheral interface. Both the microcantilever array and the on-chip signal processing circuit were fabricated on the single-crystalline silicon device layer of a silicon-on-insulator (SOI) wafer with partially depleted (PD) CMOS technology followed by three micromachining processes. The integrated microcantilever sensor makes full use of the high gauge factor of single-crystalline silicon to achieve low parasitic, latch-up, and leakage current in the PD-SOI CMOS. A measured deflection sensitivity of 0.98 × 10−6 nm−1 and an output voltage fluctuation of less than 1 μV were obtained for the integrated microcantilever. A maximum gain of 134.97 and an input offset current of only 0.623 nA were acquired for the on-chip signal processing circuit. By functionalizing the measurement microcantilevers with a biotin-avidin system method, human IgG, abrin, and staphylococcus enterotoxin B (SEB) were detected at a limit of detection (LOD) of 48 pg/mL. Moreover, multichannel detection of the three integrated microcantilever aptasensors was also verified by detecting SEB. All these experimental results indicate that the design and process of monolithically integrated microcantilevers can meet the requirements of high-sensitivity detection of biomolecules. [ABSTRACT FROM AUTHOR]

The initial-boundary value problems for the matrix Lakshmanan–Porsezian–Daniel system are studied by utilizing the Fokas unified transform approach. First, the spectral analysis of the Ablowitz–Kaup–Newell–Segur-type matrix Lax pair is performed. Second, solutions of the matrix Lakshmanan–Porsezian–Daniel system are reconstructed from a matrix Riemann–Hilbert problem. It is proved in addition that the spectral functions are not independent but are related by the so-called global relation. [ABSTRACT FROM AUTHOR]

The aim of this study was to establish a time-resolved fluorescent immunoassay (TRFIA) for the detection of serum Galectin-3 (Gal-3) and apply this method to evaluate the clinical significance of serum Gal-3 in predicting Idiopathic Membranous Nephropathy (IMN) progression. The Gal-3-TRFIA was established using the double antibody sandwich method, with the capture antibodies coated on a 96-well microplate and the detection antibodies chelated with Europium (III) (Eu3+). Serum Gal-3 was detected in 81 patients with IMN and 123 healthy controls to further evaluate the value of the Gal-3 in staging of IMN. The sensitivity of the Gal-3-TRFIA assay was 0.85 ng/mL, and the detection range was 0.85–1000 ng/mL. The Gal-3 intra-batch and inter-batch coefficients of variation were 3.45% and 5.12%, respectively. The correlation coefficient (R) between the Gal-3-TRFIA assay and commercially available enzyme-linked immunosorbent assay kits was 0.83. The serum Gal-3 concentration was higher in patients with IMN (65.57 ± 55.90 ng/mL) compared to healthy controls (16.29 ± 9.91 ng/mL, P < 0.0001). In this study, a wide detection range Gal-3-TRFIA assay was developed using lanthanide (Eu3+) chelates for the detection of Gal-3 concentrations in serum. Gal-3 concentration is elevated in patients with IMN. [ABSTRACT FROM AUTHOR]

Blockchain has critically influence on the implementations with respect to various territories. Recently, a flurry of papers, related to blockchain, are published under such background. However, most of them focus on specific topic due to space limitations, which cannot meet a high-level analysis. In this paper, lots of papers concerning blockchain, smart contracts and bitcoins are collected as many as possible such that we can carry on a comprehensive analysis on blockchain. More specifically, we construct keyword and author collaboration networks after removing the unrelated and low-quality works. Then we delve into the characteristics of complex networks, such as degree distribution, betweeness and closeness. We further present the networks with the help of visual tools like Pajek. Some unconspicuous hot topics are uncovered, with the help of complex network. These topics can in turn push the cross-field development of block chain technology, which may promote social development. [ABSTRACT FROM AUTHOR]

Malignant eyelid tumors can invade adjacent structures and pose a threat to vision and even life. Early identification of malignant eyelid tumors is crucial to avoiding substantial morbidity and mortality. However, differentiating malignant eyelid tumors from benign ones can be challenging for primary care physicians and even some ophthalmologists. Here, based on 1,417 photographic images from 851 patients across three hospitals, we developed an artificial intelligence system using a faster region-based convolutional neural network and deep learning classification networks to automatically locate eyelid tumors and then distinguish between malignant and benign eyelid tumors. The system performed well in both internal and external test sets (AUCs ranged from 0.899 to 0.955). The performance of the system is comparable to that of a senior ophthalmologist, indicating that this system has the potential to be used at the screening stage for promoting the early detection and treatment of malignant eyelid tumors. [ABSTRACT FROM AUTHOR]

K-anonymity has been gaining widespread attention as one of the most widely used technologies to protect location privacy. Nevertheless, there are still some threats such as behavior deception and service swing, since utilizing distributed k-anonymity technology to construct an anonymous domain. More specifically, the coordinate of the honest node will be a leak if the malicious nodes submit wrong locations coordinate to take part in the domain construction process. Worse still, owing to service swing, the attacker increases the reputation illegally to deceive honest nodes again. To overcome those drawbacks, we propose a trusted de-swinging k-anonymity scheme for location privacy protection. Primarily, we introduce a de-swinging reputation evaluation method (DREM), which designs a penalty factor to curb swinging behavior. This method calculates the reputation from entity honesty degree, location information entropy, and service swing degree. Besides, based on our proposed DREM, a credible cloaking area is constructed to protect the location privacy of the requester. In the area, nodes can choose some nodes with a high reputation for completing the construction process of the anonymous domain. Finally, we design reputation contracts to calculate credit automatically based on smart contracts. The security analysis and simulation results indicate that our proposed scheme effectively resists malicious attacks, curbs the service swing, and encourages nodes to participate honestly in the construction of cloaking areas. [ABSTRACT FROM AUTHOR]

Acquisition of the direct electrochemical response of protein is the cornerstone for the development of the third generation of electrochemical biosensors. In this work, we developed a nanocluster-assisted protein-film voltammetry technique (NCA-PFV) which can achieve the acquisition of the electrochemical signal and maintain the activity without affecting of the protein's structure. With this strategy, a lipid bilayer membrane is used to immobilize the membrane protein so as to maintain its natural state. Copper nanoclusters with a size smaller than most proteins are then used to function at sub-protein scale and to mediate the electron hopping from the electroactive center of the electrode. As a model, the direct electrochemical signal of cyclooxygenase (COX) is successfully obtained, with a pair of well-defined redox peaks located at −0.39 mV and −0.31 mV, which characterize the heme center of the enzyme. Its catalytic activity towards the substrate arachidonic acid (AA) is also retained. The detection range for AA is 10–1000 μM and the detection limit is 2.4 μM. Electrochemical monitoring of the regulation of the catalytic activity by an inhibitor DuP-697 is also achieved. This work provides a powerful tool for the fabrication of enzyme-based electrochemical biosensors, and is also of great significance for promoting the development and application of next-generation electrochemical biosensors. [ABSTRACT FROM AUTHOR]

Network virtualization is a promising solution to attack Internet ossification. Virtual network mapping (or embedding) problem is the core of it and is proved to be NP-hard. In this paper, virtual network mapping problem with survivability is formulated and solved with a heuristic algorithm. Firstly, network link resources are divided into primary flow resources and secondary flow resources. The former are used under normal network operation, whereas the latter are used as backup resources once the networks fail. Secondly, we introduce a novel metric named global resource capacity (GRC) which is recently proposed for measuring node mapping capacity to improve network load balance. At last, a heuristic survivable virtual network embedding algorithm (GRC-SVNE) is proposed. In node mapping phase, we calculate the mapping capacity of all nodes and then some nodes are selected as candidate nodes for virtual network embedding and the goal is to improve mapping successful ratio. After that, link mapping is performed with Dijkstra algorithm. Simulation results show that GRC-SVNE outperforms the traditional greedy algorithm (GREEDY), randomized algorithm (R-ViNE) as well as deterministic algorithm (D-ViNE) and demonstrates desirable results in terms of acceptance ratio, network load balance and network revenue. [ABSTRACT FROM AUTHOR]

Network embedding is an important pre-process for analysing large scale information networks. Several network embedding algorithms have been proposed for unsigned social networks. However, these methods cannot be simply migrate to signed social networks which have both positive and negative relationships. In this paper, we present our signed social network embedding model which is based on the word embedding model. To deal with two kinds of links, we define two relationships: neighbour relationship and common neighbour relationship, as well as design a bias random walk procedure. In order to further improve interpretation of the representation vectors, the follow-proximally-regularized-leader online learning algorithm is introduced to the traditional word embedding framework to acquire sparse representations. Extensive experiments were carried out to compare our algorithm with three state-of-the-art methods for community detection and sign prediction tasks. The experimental results demonstrate that our algorithm performs better than the comparison algorithms on most signed social networks. [ABSTRACT FROM AUTHOR]

Purpose: Individuals predisposed to vasovagal syncope may have different autonomic nervous system control mechanisms from those without predisposition to vasovagal events. To test this hypothesis, we investigated different sympathetic responses in a canine model of vasovagal syncope.Methods: Left thoracotomy was performed on 20 mongrel dogs. The heart was exposed and a bolus of veratridine (15 μg/kg), a neurotoxin which prevents the inactivation of sodium ion channels, was injected into the left atrium to induce a Bezold-Jarisch reflex-mediated vasovagal event, characterized by bradycardia, decreased inotropism, and hypotension. Electrocardiogram and blood pressure were continuously monitored. Neural activity was recorded from the left stellate ganglion. Plasma norepinephrine and acetylcholine levels were measured 30 s before and 30 s after veratridine injection.Results: Veratridine resulted in rapid decreases in heart rate and blood pressure in all dogs, accompanied by increases in both norepinephrine and acetylcholine. Two types of neural activity (high-amplitude spike discharge activity and low-amplitude burst discharge activity) were recorded from the left stellate ganglion. Veratridine induced high-frequency spike discharge activity in some dogs (Group A), whereas spike discharge activity was scarce and relatively unresponsive to veratridine in the remaining dogs (Group B). Dogs in Group A had higher plasma norepinephrine levels (111.63 ± 15.1 vs. 48.11 ± 33.81 ng/l, p = 0.002) and less intense drops in heart rate (− 37 ± 24 vs. − 84 ± 28 bpm, p = 0.001) and blood pressure (systolic blood pressure, − 18 ± 15 vs. − 37 ± 13 mmHg, p = 0.009; diastolic blood pressure, − 26 ± 13 vs. − 45 ± 13 mmHg, p = 0.005) compared to dogs in Group B. Similarly, heart rate post-veratridine was higher (102 ± 23 vs. 69 ± 22 bpm, p = 0.004), the veratridine-induced longest RR interval was shorter (0.7 [0.5-0.8] vs. 1.2 [1.1-3.5] s, p < 0.001) and the diastolic and mean arterial pressures post-veratridine were higher (all p < 0.05) in dogs in Group A compared to those in Group B.Conclusions: Distinct sympathetic activation as represented by left stellate ganglion high-frequency spike discharge activity protected against bradycardia and hypotension in a canine model of vasovagal syncope. Our findings may have therapeutic implications. [ABSTRACT FROM AUTHOR]