Heartwood of Dalbergia cochinchinensis: 4,7,2'-Trihydroxy-4'-methoxyisoflavanol and 6,4'-Dihydroxy-7-methoxyflavane Reduce Cytokine and Chemokine Expression In Vitro.

Dalbergia cochinchinensis has been widely used in traditional medicine because of its flavonoids; however, the impact of the flavonoids to modulate the inflammatory response to oral cells remains to be described. For this aim, we isolated 4,7,2'-trihydroxy-4'-methoxyisoflavanol (472T4MIF) and 6,4'-dihydroxy-7-methoxyflavane (64D7MF) from the heartwood of D. cochinchinensis and confirmed the chemical structure by nuclear magnetic resonance. We show here that both flavonoids are inhibitors of an inflammatory response of murine RAW 264.7 inflammatory macrophages stimulated by LPS. This is indicated by interleukin (IL)1, IL6, and chemokine CCL2 production besides the phosphorylation of p65. Consistently, in primary murine macrophages, both flavonoids decreased the inflammatory response by lowering LPS-induced IL1 and IL6 expression. To introduce oral cells, we have used human gingival fibroblasts and provoked the inflammatory response by exposing them to IL1β and TNFα. Under these conditions, 472T4MIF, but not 64D7MF, reduced the expression of chemokines CXCL1 and CXCL2. Taken together, we identified two flavonoids that can reduce the expression of cytokines and chemokines in macrophages and fibroblastic cells

Biomechanical Effects of a Cross Connector in Sacral Fractures – A Finite Element Analysis

Background: Spinopelvic fractures and approaches of operative stabilization have been a source of controversial discussion. Biomechanical data support the benefit of a spinopelvic stabilization and minimally invasive procedures help to reduce the dissatisfying complication rate. The role of a cross connector within spinopelvic devices remains inconclusive. We aimed to analyze the effect of a cross connector in a finite element model (FE model). Study Design: A FE model of the L1-L5 spine segment with pelvis and a spinopelvic stabilization was reconstructed from patient-specific CT images. The biomechanical relevance of a cross connector in a Denis zone I (AO: 61-B2) sacrum fracture was assessed in the FE model by applying bending and twisting forces with and without a cross connector. Biomechanical outcomes from the numerical model were investigated also considering uncertainties in material properties and levels of osseointegration. Results: The designed FE model showed comparable values in range-of-motion (ROM) and stresses with reference to the literature. The superiority of the spinopelvic stabilization (L5/Os ilium) ± cross connector compared to a non-operative procedure was confirmed in all analyzed loading conditions by reduced ROM and principal stresses in the disk L5/S1, vertebral body L5 and the fracture area. By considering the combination of all loading cases, the presence of a cross connector reduced the maximum stresses in the fracture area of around 10%. This difference has been statistically validated (p < 0.0001). Conclusion: The implementation of a spinopelvic stabilization (L5/Os ilium) in sacrum fractures sustained the fracture and led to enhanced biomechanical properties compared to a non-reductive procedure. While the additional cross connector did not alter the resulting ROM in L4/L5 or L5/sacrum, the reduction of the maximum stresses in the fracture area was significant. © Copyright © 2021 Gierig, Liu, Weiser, Lehmann, Wriggers, Marino and Saul

Design Principle and Development Trends of Silicon-Based Anode Binders for Lithium-ion Batteries: A Mini Review

Abstract: Silicon (Si), recognized as a promising alternative material for the anodes of lithium-ion batteries, boasts a high theoretical specific capacity and abundant natural availability. During the preparation of silicon-based anodes, binders play a pivotal role in ensuring the cohesion of silicon particles, conductive agents, and current collectors. The structure and performance of these binders are critical for the mechanical stability, electrical conductivity, and stress dissipation capacity of the anodes. This review initially outlines the structural characteristics of various binders, including linear, branched, and three-dimensional cross-linked types. It then delves into the relationship between the structure and properties of these binders in the context of their application in high-performance lithium-ion batteries, focusing on their mechanical properties, electrical conductivity, and self-healing capabilities. Particular attention is given to the design strategies for binders that facilitate stress dissipation, with an emphasis on integrating multifunctional polymer binders renowned for their superior conductive and self-healing features. Such binders contribute to the formation of a robust three-dimensional network structure via multiple bonding mechanisms, including chemical, non-covalent, and coordination interactions. This configuration significantly enhances the adhesion between silicon particles, thereby facilitating the efficient dissipation of stress, which is a key aspect for ensuring the long-term cycling stability of lithium-ion batteries. Lastly, the paper explores future development directions for silicon anode binders, advocating for a thorough investigation into the synergy of diverse structural and functional combinations, with the aim of advancing the performance and practical application of silicon-based lithium-ion batteries

Large genomic fragment deletion and functional gene cassette knock-in via Cas9 protein mediated genome editing in one-cell rodent embryos

The CRISPR-Cas RNA-guided system has versatile uses in many organisms and allows modification of multiple target sites simultaneously. Generating novel genetically modified mouse and rat models is one valuable application of this system. Through the injection of Cas9 protein instead of mRNA into embryos, we observed fewer off-target effects of Cas9 and increased point mutation knock-in efficiency. Large genomic DNA fragment (up to 95 kb) deletion mice were generated for in vivo study of lncRNAs and gene clusters. Site-specific insertion of a 2.7 kb CreERT2 cassette into the mouse Nfatc1 locus allowed labeling and tracing of hair follicle stem cells. In addition, we combined the Cre-Loxp system with a gene-trap strategy to insert a GFP reporter in the reverse orientation into the rat Lgr5 locus, which was later inverted by Cre-mediated recombination, yielding a conditional knockout/reporter strategy suitable for mosaic mutation analysis

Learning efficient binary representation for images with unsupervised deep neural networks

Coding deficiency, which refers to information insufficiency a code can carry, is one of the barriers to high-performance representation learning. Unsupervised binary representations have broader applications than other representations but suffer from the same problem. This work addresses the coding deficiency from two perspectives: biases on single binary neurons and correlation between pairs. A normalization layer and a mutual information loss are introduced to encourage lower code bias and less conflict when learning unsupervised hash for images. Learning uniform distribution for binary neurons is crucial to keep every learned bit informative, which motivates the proposed normalized binary layer. Experiments suggest that the proposed normalization can enhance the code quality by having lower biases, especially in small code lengths. Also, a mutual information loss on individual stochastic binary neurons is proposed to reduce the correlation between binary neurons, discouraging code conflict by minimizing mutual information on the learned binary representation and diverging the code distribution before optimizing it in the next epoch. Performance benchmarks on image retrieval with the unsupervised binary code is conducted on four open datasets. Both the proposed approaches help the model to achieve state-of-the-art accuracy on image retrieval task for all those datasets, which validates their effectiveness in improving unsupervised hashing efficiency.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat

Achieving near unity power factor in three-phase diode bridge rectifier-inverter structure

This research project makes an effort to improve the input power factor as well as reduce input current total harmonic distortion for three-phase diode bridge rectifier-inverter structure. The thesis mainly covers the following aspects: develop a near unity power factor converter topology and investigate the effect of voltage unbalance in the proposed rectifier-inverter drive system. Laboratory hardware prototypes have been developed and successfully verified the initial design. Depending on the application of suitable control methods, the proposed rectifier-inverter topology can be applied to high power as well as low to mid power application.DOCTOR OF PHILOSOPHY (EEE