73 research outputs found

    Extraction of essential oil from the aerial parts of Artemisia frigida Willd by way of hydrodistillation

    Get PDF
    This study aims to determine the optimum conditions for extraction of essential oil compounds in the aerial parts of Artemisia frigida Willd. Method: the considered extraction method is hydro-distillation, using a Clevenger apparatus. The effect of particle size of raw material, soaking time, liquid to plant material ratio and extraction time on essential oil yield were investigated through both single factor and multi-factor experiments. Results: In the single factor experiment, the influences of the following factors on essential oil extraction were studied; particle size 0.825 mm, soaking time 2 h, and liquid to plant material ratio 12:1. Under the multi-factor experiment, the influences of multiple factors of extraction conditions on essential oil were considered, particularly, extraction time (C)>soaking time (A)>liquid to plant material ratio. Conclusion: For extraction of essential oil from the aerial parts of Artemisia frigida Willd, the following optimum extraction parameters were identified: 2h of soaking time, 10:1 liquid to solid ratio, and 8h of extraction time

    Augmented reality-based visual-haptic modeling for thoracoscopic surgery training systems

    Get PDF
    Background: Compared with traditional thoracotomy, video-assisted thoracoscopic surgery (VATS) has less minor trauma, faster recovery, higher patient compliance, but higher requirements for surgeons. Virtual surgery training simulation systems are important and have been widely used in Europe and America. Augmented reality (AR) in surgical training simulation systems significantly improve the training effect of virtual surgical training, although AR technology is still in its initial stage. Mixed reality has gained increased attention in technology-driven modern medicine but has yet to be used in everyday practice. Methods: This study proposed an immersive AR lobectomy within a thoracoscope surgery training system, using visual and haptic modeling to study the potential benefits of this critical technology. The content included immersive AR visual rendering, based on the cluster-based extended position-based dynamics algorithm of soft tissue physical modeling. Furthermore, we designed an AR haptic rendering systems, whose model architecture consisted of multi-touch interaction points, including kinesthetic and pressure-sensitive points. Finally, based on the above theoretical research, we developed an AR interactive VATS surgical training platform. Results: Twenty-four volunteers were recruited from the First People's Hospital of Yunnan Province to evaluate the VATS training system. Face, content, and construct validation methods were used to assess the tactile sense, visual sense, scene authenticity, and simulator performance. Conclusions: The results of our construction validation demonstrate that the simulator is useful in improving novice and surgical skills that can be retained after a certain period of time. The video-assisted thoracoscopic system based on AR developed in this study is effective and can be used as a training device to assist in the development of thoracoscopic skills for novices

    Bis(η3-2-tert-butyl-1-trimethyl­silyl-3-phenyl-1-aza­all­yl)nickel(II)

    Get PDF
    The title compound, [Ni(C15H24NSi)2], is a homoleptic metal–η3-aza­allyl centrosymmetric complex containing two aza­allyl ligands bound in an η3-manner to an NiII atom located on a center of symmetry. The overall coordination about the NiII atom is square-planar. The C and N atoms of the aza­allyl group are sp 2-hybridized. The uneven Ni—C and Ni—N distances [2.045 (5)/2.060 (6) and 1.916 (5) Å] are influenced by a steric hindering effect from the nearby benzene ring

    Essential Genetic Interactors of SIR2 Required for Spatial Sequestration and Asymmetrical Inheritance of Protein Aggregates

    Get PDF
    Sir2 is a central regulator of yeast aging and its deficiency increases daughter cell inheritance of stress-and aging-induced misfolded proteins deposited in aggregates and inclusion bodies. Here, by quantifying traits predicted to affect aggregate inheritance in a passive manner, we found that a passive diffusion model cannot explain Sir2-dependent failures in mother-biased segregation of either the small aggregates formed by the misfolded Huntingtin, Htt103Q, disease protein or heat-induced Hsp104-associated aggregates. Instead, we found that the genetic interaction network of SIR2 comprises specific essential genes required for mother-biased segregation including those encoding components of the actin cytoskeleton, the actin-associated myosin V motor protein Myo2, and the actin organization protein calmodulin, Cmd1. Co-staining with Hsp104-GFP demonstrated that misfolded Htt103Q is sequestered into small aggregates, akin to stress foci formed upon heat stress, that fail to coalesce into inclusion bodies. Importantly, these Htt103Q foci, as well as the ATPase-defective Hsp104(Y662A)-associated structures previously shown to be stable stress foci, co-localized with Cmd1 and Myo2-enriched structures and super-resolution 3-D microscopy demonstrated that they are associated with actin cables. Moreover, we found that Hsp42 is required for formation of heat-induced Hsp104(Y662A) foci but not Htt103Q foci suggesting that the routes employed for foci formation are not identical. In addition to genes involved in actin-dependent processes, SIR2-interactors required for asymmetrical inheritance of Htt103Q and heat-induced aggregates encode essential sec genes involved in ER-to-Golgi trafficking/ER homeostasis

    VaBUS: Edge-Cloud Real-Time Video Analytics via Background Understanding and Subtraction

    Get PDF
    Edge-cloud collaborative video analytics is transforming the way data is being handled, processed, and transmitted from the ever-growing number of surveillance cameras around the world. To avoid wasting limited bandwidth on unrelated content transmission, existing video analytics solutions usually perform temporal or spatial filtering to realize aggressive compression of irrelevant pixels. However, most of them work in a context-agnostic way while being oblivious to the circumstances where the video content is happening and the context-dependent characteristics under the hood. In this work, we propose VaBUS, a real-time video analytics system that leverages the rich contextual information of surveillance cameras to reduce bandwidth consumption for semantic compression. As a task-oriented communication system, VaBUS dynamically maintains the background image of the video on the edge with minimal system overhead and sends only highly confident Region of Interests (RoIs) to the cloud through adaptive weighting and encoding. With a lightweight experience-driven learning module, VaBUS is able to achieve high offline inference accuracy even when network congestion occurs. Experimental results show that VaBUS reduces bandwidth consumption by 25.0%-76.9% while achieving 90.7% accuracy for both the object detection and human keypoint detection tasks

    Ginger Compound [6]-Shogaol and Its Cysteine-Conjugated Metabolite (M2) Activate Nrf2 in Colon Epithelial Cells in Vitro and in Vivo

    Get PDF
    In this study, we identified Nrf2 as a molecular target of [6]-shogaol (6S), a bioactive compound isolated from ginger, in colon epithelial cells in vitro and in vivo. Following 6S treatment of HCT-116 cells, the intracellular GSH/GSSG ratio was initially diminished but was then elevated above the basal level. Intracellular reactive oxygen species (ROS) correlated inversely with the GSH/GSSG ratio. Further analysis using gene microarray showed that 6S upregulated the expression of Nrf2 target genes (AKR1B10, FTL, GGTLA4, and HMOX1) in HCT-116 cells. Western blotting confirmed upregulation, phosphorylation, and nuclear translocation of Nrf2 protein followed by Keap1 decrease and upregulation of Nrf2 target genes (AKR1B10, FTL, GGTLA4, HMOX1, and MT1) and glutathione synthesis genes (GCLC and GCLM). Pretreatment of cells with a specific inhibitor of p38 (SB202190), PI3K (LY294002), or MEK1 (PD098059) attenuated these effects of 6S. Using ultra-high-performance liquid chromatography–tandem mass spectrometry, we found that 6S modified multiple cysteine residues of Keap1 protein. In vivo 6S treatment induced Nrf2 nuclear translocation and significantly upregulated the expression of MT1, HMOX1, and GCLC in the colon of wild-type mice but not Nrf2–/– mice. Similar to 6S, a cysteine-conjugated metabolite of 6S (M2), which was previously found to be a carrier of 6S in vitro and in vivo, also activated Nrf2. Our data demonstrated that 6S and its cysteine-conjugated metabolite M2 activate Nrf2 in colon epithelial cells in vitro and in vivo through Keap1-dependent and -independent mechanisms
    corecore