Complexity of gradient projection method for optimal routing indata networks

In this paper, we derive a time-complexity bound for the gradient projection method for optimal routing in data networks. This result shows that the gradient projection algorithm of Goldstein-Levitin-Poljak type formulated by Bertsekas (1982), Bertsekas and Gallager (1987) and Bertsekas et al. (1984) converges to within ε in relative accuracy in O(ε^-2h_minN_max) number of iterations, where N_max is the number of paths sharing the maximally shared link, and h_min is the diameter of the network. Based on this complexity result, we also show that the one-source-at-a-time update policy has a complexity bound which is O(n) times smaller than that of the all-at-a-time update policy, where n is the number of nodes in the network. The result of this paper argues for constructing networks with low diameter for the purpose of reducing complexity of the network control algorithms. The result also implies that parallelizing the optimal routing algorithm over the network nodes is beneficial     

Wide-band guided-wave acoustooptic Bragg cells in GaAs-GaAlAs waveguide

One of the key components in future GaAs-based monolithic integrated acoustooptic modules or circuits is an efficient and wide-band acoustooptic Bragg cell. In this paper, design, fabrication, and performance characteristics of compact miniaturized GaAs-GaAlAs waveguide acoustooptic Bragg cells that operate at the acoustic frequency from 190 to 625 MHz are reported. A 201 MHz bandwidth has been obtained with the Bragg cell that employs a single tilted-finger chirp transducer centering at 360 MHz. The acoustic propagation losses in the GaAs-GaAlAs waveguides that were measured using acoustooptic Bragg diffraction as a probe are also presented.     

Object-oriented development and application of a nonlinear structural analysis framework

This paper describes the framework and application of numerical simulation software on earthquake engineering research and practice. The analysis kernel is developed at the National Center for Research on Earthquake Engineering (NCREE) and is entitled as “Platform of Inelastic Structural Analysis for 3D systems (PISA3D)”. The design of PISA3D framework adopts the Design Pattern and the Unified Process. PISA3D provides structural modeling and high computational efficiency for engineers and researchers to simulate the responses of nonlinear systems under various kinds of load effects. It includes static or cyclic loads, displacements, earthquake ground accelerations, and earthquake aftershocks. PISA3D is easy to extend and maintain due to its object-oriented nature. Advanced users can derive or compose its objects’ libraries to perform different types of structural analyses. Based on object-oriented techniques, VISA3D (Visualization of Inelastic Structural Analysis for 3D systems) has been implemented with usage of OpenGL for 3D graphics and MFC for graphical user interface (GUI). Its framework allows further extension on new input formats and new element types. VISA3D has been mainly developed as a post-processor to examine the analytical results of PISA3D through 2D/3D static or dynamic graphic approaches. It includes graphical checking of the structural model, mode shapes, deformations, extents and locations of plastic hinges, plotting of nodal velocity, acceleration, and energy distribution time histories. This paper then introduces NCREE’s recent development on the pre-processing framework GISA3D (Graphical Interface of Inelastic Structural Analysis for 3D systems). The GISA3D does not only supply features as a “post-processor”, but also fully supports operations of “model generation” via mouse motion. Users can create, remove, modify and set elements/nodes through mouse clicking, dragging and selecting. Finally, this paper illustrates the networked sub-structural pseudo dynamic tests using PISA3D as the analysis engine, and concludes with several successful applications of PISA3D/VISA3D/GISA3D on various researches and actual structural engineering projects.     

Genetic Variation of Maize Hybrids in Grain Yield Response to Potassium and Inhibiting Nitrification

Nine maize hybrids were grown under five N levels with or without a nitrification inhibitor (nitrapyrin or an experimental inhibitor, XDE474) to evaluate the effect of inhibiting nitrification on grain yield performance and cannibalisation of nutrients from vegetative tissues during kernel maturation. Grain yield response of these hybrids also was evaluated under a paired combination of four N levels and two K levels. Hybrids responded differently to N, the form of N, and K treatments, and there appeared to be a genetic basis for preference of the form of N (ammonium versus nitrate nitrition). Crosses that involved the Mo17 family responded positively to inhibiting nitrification which provided a larger portion of the N in the ammonium form, but incorporation of early maturing genes reduced the positive response to ammonium nutrition. Like ammonium nutrition, maize hybrids showed a differential response to K treatments, and the availability of a large amount of K early in the growing season produced a negative effect on grain yield. The experimental nitrification inhibitor, XDE474, was more effective than nitrapyrin in increasing grain yield and minimising cannibalisation of nutrients in the leaf tissue.     

Self-assisted wound healing using piezoelectric and triboelectric nanogenerators

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An Innovative Customized Biomimetic Hydrogel for Drug Screening Application Potential: Biocompatibility and Cell Invasion Ability

The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications.     

FAK in Cancer: From Mechanisms to Therapeutic Strategies

Focal adhesion kinase (FAK), a non-receptor tyrosine kinase, is overexpressed and activated in many cancer types. FAK regulates diverse cellular processes, including growth factor signaling, cell cycle progression, cell survival, cell motility, angiogenesis, and the establishment of immunosuppressive tumor microenvironments through kinase-dependent and kinase-independent scaffolding functions in the cytoplasm and nucleus. Mounting evidence has indicated that targeting FAK, either alone or in combination with other agents, may represent a promising therapeutic strategy for various cancers. In this review, we summarize the mechanisms underlying FAK-mediated signaling networks during tumor development. We also summarize the recent progress of FAK-targeted small-molecule compounds for anticancer activity from preclinical and clinical evidence.     

Gut Mucosal Microbiome Is Perturbed in Rheumatoid Arthritis Mice and Partly Restored after TDAG8 Deficiency or Suppression by Salicylanilide Derivative

Rheumatoid arthritis (RA), an autoimmune disease, is characterized by chronic joint inflammation and pain. We previously found that the deletion of T-cell death-associated gene 8 (TDAG8) significantly reduces disease severity and pain in RA mice. Whether it is by modulating gut microbiota remains unclear. In this study, 64 intestinal samples of feces, cecal content, and cecal mucus from the complete Freund’s adjuvant-induced arthritis mouse models were compared. The α- and β-diversity indices of the microbiome were significantly lower in RA mice. Cecal mucus showed a higher ratio of Firmicutes to Bacteroidetes in RA than healthy mice, suggesting the ratio could serve as an RA indicator. Four core genera, Eubacterium_Ventriosum, Alloprevotella, Rikenella, and Treponema, were reduced in content in both feces and mucus RA samples, and could serve microbial markers representing RA progression. TDAG8 deficiency decreased the abundance of proinflammation-related Eubacterium_Xylanophilum, Clostridia, Ruminococcus, Paraprevotella, and Rikenellaceae, which reduced local mucosal inflammation to relieve RA disease severity and pain. The pharmacological block of the TDAG8 function by a salicylanilide derivative partly restored the RA microbiome to a healthy composition. These findings provide a further understanding of specific bacteria interactions with host gut mucus in the RA model. The modulation by TDAG8 on particular bacteria can facilitate microbiota-based therapy.