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The reliability of the immersed tunnel element joint is the key to determine whether the immersed tunnel can operate safely. At present, the immersed tunnel monitoring mostly pays attention to the joint opening and closing amount and neglects the differential deformation of the joint. Based on the immersed tunnel of Hong Kong-Zhuhai-Macao Bridge, combined with the operating environment and structural characteristics of the immersed tunnel, this paper introduces a close-range photogrammetry method to monitor the differential deformation of the immersed tunnel element joint. Through theoretical analysis, software and hardware development, laboratory test and field test, the paper puts forward puts forward a comprehensive multi-parameter evaluation and screening algorithm of boundary fitting ellipse based on fitting rate, ellipticity and area difference and a micro-displacement correction algorithm for camera based on three-dimensional calibration object, and develops an automatic monitoring system equipment for differential deformation of immersed tunnel element joint. Upon tests in tunnels, the monitoring equipment is proven in automatic monitoring on differential deformation of immersed tunnel element joints. This equipment has been successfully applied to the E31~E32 element joint of Hong Kong-Zhuhai-Macao Bridge immersed tunnel, which verifies the effectiveness of the equipment from the perspective of practical engineering application.

Aim: Aseptic meningitis is an unfortunate complication after craniotomy. Continuous lumbar drainage is a safe and effective method for treating postcraniotomy aseptic meningitis. This study compared the incidence of cerebrospinal fluid (CSF) leakage around the tube at the skin exit site and infection associated with tubes placed in two different ways. Patients and Methods: The study enrolled 140 consecutive patients with postoperative aseptic meningitis manifesting as headache and fever and managed by lumbar external drainage (LED) between June 2014 and July 2018. From June 2014 to Jan 2016, an LED catheter was set in a conventional fashion without a subcutaneous tunnel. From Feb 2016 to July 2018, we adopted a modified mode of placing the LED catheter with a subcutaneous tunnel. Drain-related CSF leakage and infection were analyzed between the two groups. Results: Postoperative aseptic meningitis can be easily managed through lumbar CSF drainage. The incidences of drain-associated infection and CSF leakage were 20% and 7.14%, respectively, in group 1 (without subcutaneous tunnels) and 7.14% and 4.28%, respectively, in group 2 (with subcutaneous tunnels). CSF leakage was significantly reduced in group 2 compared to group 1 (P

The construction of 2-edge fault tolerant(Q(sub n)) (2-EFT(Q(sub n))) graphs and 3-EFT(Qn) graphs, where n is arbitrarily large, give multiple-edge-fault tolerance with respect to hypercubes computer networks. The scheme adds log n extra degree to the vertices of Q(sub n) for two-edge-fault tolerance and another degree for three-edge-fault tolerance. The edges represent the communication links between pairs of processors in interconnection networks.

A new algorithm is developed based on Kirchoff's matrix-tree theorem to determine the most vital edge of a graph. The most vital edge with respect to spanning trees is the edge which exhibits a severe decrease in the number of spanning trees. The asymptotic complexity of the algorithm can be converted to a fast matrix multiplication routine. The conversion facilitates the determination of the vital edge.

Co has been proposed as one of the most promising candidates to replace W or Cu in interconnects, where Co–Ti could be used as a single barrier/liner to prevent Co out-diffusion into dielectric and Si substrate as well as to enhance the adhesion property. In this paper, the material and electrical properties of Co/Co-Ti/n+-Si contacts with different compositions and thicknesses of Co–Ti, with and without Ge pre-amorphization implantation (Ge PAI) were investigated elaborately. Sheet resistance, phase formation, interfacial morphology and element distribution were comprehensively characterized in terms of four-point probe, X-ray diffraction and high-resolution transmission electron microscopy in combination with corresponding energy dispersive X-ray spectroscopy respectively. Meanwhile, the specific contact resistivity (ρc) was extracted using refined transmission line model structures, and it is found that Ge PAI is indeed beneficial in reducing ρc values in Co/Co-Ti/n+-Si contacts. With the assistance of Ge PAI, the lowest ρc value of 8.56 × 10−9 Ω cm2 is accomplished for Co/Co0.65Ti0.35/n+-Si contacts, which is a ∼47.8% reduction in contrast to that without Ge PAI. [ABSTRACT FROM AUTHOR]

Background: Pilocytic astrocytomas (PAs) are slow growing neoplasms and usually located at the cerebellum. There has been certainty regarding the truthful benefit of surgical resection for patients with PA. Gross total resection (GTR) of PAs, especially those being situated in deep regions, remains a surgical challenge. Generally, they are considered as benign and usually develop in young patients. PAs, belonging to WHO I can be cured by radical resection. The patients with PA have excellent prognosis if complete resection can be conducted. The use of fluorescein in vermis PA surgery has not been yet reported. Our data presents fluorescein facilitates surgical resection of vermis PA. Methods: Five milligrams per kilogram of fluorescein sodium was intravenously injected directly before general anesthesia for the three patients with PA. The yellow 560 filter was employed for microsurgical tumor resection. Surgical outcomes were assessed concerning the extent of resection. Results: Most portion of PA in the three cases was found to be highly fluorescent after intravenous fluorescein sodium injection, which markedly enhanced tumor visibility. Gross total resection in all of the patients was achieved without further neurological deficits. No adverse effects and complications resulting from fluorescein sodium were observed over the postoperative course. Conclusions: Intraoperative guidance by fluorescein sodium as a new, simple, safe, and practical procedure can enhance the fidelity of tumor tissue and increase the possibility of completely resecting PAs. [ABSTRACT FROM AUTHOR]

A silver-catalyzed chemoselective [4+2] annulation of aryl and heteroaryl isocyanides with α-substituted isocyanoacetamides was developed for the facile and efficient synthesis of 2-aminoquinolones, naphthyridines, and phenanthrolines. A mechanism for this multistep domino reaction is proposed on the basis of a 13C-labeling experiment, according to which an unprecedented chemoselective heterodimerization of two different isocyanides generates an α-amidoketenimine intermediate, which undergoes 1,3-amino migration to form an α-imidoylketene, followed by 6 π electrocyclization. [ABSTRACT FROM AUTHOR]

A DBU-catalyzed aerobic oxidative Robinson annulation of 2-isocyanochalcones with active methylene ketones was developed for the expedient synthesis of phenanthridines in high to excellent yields. This unprecedented multistep domino reaction represents a new strategy for the construction of this tricyclic scaffold by the sequential formation of two rings and three C–C bonds in a single operation at room temperature. [ABSTRACT FROM AUTHOR]

A new cross-cycloaddition reaction between a wide range of isocyanides and 2-isocyanochalcones (or analogues) was developed for the expeditious synthesis of pyrrolo[3,4-b]indoles under thermal conditions. On the basis of the experimental results and DFT calculations, a mechanism for this domino reaction is proposed involving chemoselective heterodimerization of two different isocyanides to form 1,4-diazabutatriene intermediates, followed by an intramolecular [3+2]-cycloaddition and 1,3-proton shift. [ABSTRACT FROM AUTHOR]

Presents a construction scheme for k-edge-fault-tolerant graphs (k-EFT) with respect to hypercubes (Q sub n) of arbitrarily large n dimensions, where k equals 2 and 3. Definition and notation of hypercubes; Addition of an approximately `log n' extra degree to Q sub n for 2-edge-fault tolerance; Construction of the 2-EFT (Q sub n) and 3-EFT (Q sub n) graphs.