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Ya-Chun Chu,1,2,* Hsu-Wei Fang,2,3,* Yu-Yi Wu,1 Yu-Jun Tang,1 Erh-Hsuan Hsieh,1 YiZhou She,4 Che-Yi Chang,1 I-Chan Lin,5,6 Yin-Ju Chen,1,7– 9 Guei-Sheung Liu,1,10– 12 Ching-Li Tseng1,8,9,13 1Graduate Institute of Biomedical Materials and Tissue Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei City, Taiwan; 2Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei City, Taiwan; 3Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli County, Taiwan; 4School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei City, Taiwan; 5Department of Ophthalmology, Wan Fang Hospital, Taipei Medical University, Taipei City, Taiwan; 6Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei City, Taiwan; 7Department of Radiation Oncology, Taipei Medical University Hospital, Taipei City, Taiwan; 8International Ph.D. Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei City, Taiwan; 9Center for Precision Medicine and Translational Cancer Research, Taipei Medical University Hospital, Taipei City, Taiwan; 10Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia; 11Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, VIC, Australia; 12Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia; 13Research Center of Biomedical Device, College of Biomedical Engineering, Taipei Medical University, Taipei City, Taiwan*These authors contributed equally to this workCorrespondence: Ching-Li Tseng, Tel +886 2 2736 1661 (ext. 5214), Email chingli@tmu.edu.twBackground: Corneal neovascularization (NV) is a process of abnormal vessel growth into the transparent cornea from the limbus and can disturb the light passing through the cornea, resulting in vision loss or even blindness. The use of nanomedicine as an effective therapeutic formulation in ophthalmology has led to higher drug bioavailability and a slow drug release rate. In this research, we designed and explored the feasibility of a new nanomedicine, gp91 ds-tat (gp91) peptide-encapsulated gelatin nanoparticles (GNP-gp91), for inhibiting corneal angiogenesis.Methods: GNP-gp91 were prepared by a two-step desolvation method. The characterization and cytocompatibility of GNP-gp91 were analyzed. The inhibition effect of GNP-gp91 on HUVEC cell migration and tube formation was observed by an inverted microscope. The drug retention test in mouse cornea was observed by in vivo imaging system, fluorescence microscope, and DAPI/TAMRA staining. Finally, the therapeutic efficacy and evaluation of neovascularization-related factors were conducted through the in vivo corneal NV mice model via topical delivery.Results: The prepared GNP-gp91 had a nano-scale diameter (550.6 nm) with positive charge (21.7 mV) slow-release behavior (25%, 240hr). In vitro test revealed that GNP-gp91 enhanced the inhibition of cell migration and tube formation capacity via higher internalization of HUVEC. Topical administration (eyedrops) of the GNP-gp91 significantly prolongs the retention time (46%, 20 min) in the mouse cornea. In chemically burned corneal neovascularization models, corneal vessel area with a significant reduction in GNP-gp91 group (7.89%) was revealed when compared with PBS (33.99%) and gp91 (19.67%) treated groups via every two days dosing. Moreover, GNP-gp91 significantly reduced the concentration of Nox2, VEGF and MMP9 in NV’s cornea.Conclusion: The nanomedicine, GNP-gp91, was successfully synthesized for ophthalmological application. These data suggest that GNP-gp91 contained eyedrops that not only have a longer retention time on the cornea but also can treat mice corneal NV effectively delivered in a low dosing frequency, GNP-gp91 eyedrops provides an alternative strategy for clinical ocular disease treatment in the culture.Keywords: gp91 peptide, gelatin, nanoparticles, ocular retention, control release, corneal neovascularization, eye drops

Aeromonas hydrophila is a Gram-negative bacterium that is a critical causative agent of infections in fish and is occasionally responsible for human infections following contact with contaminated w...

We propose a high sensitivity optical fiber sensor for detecting the acoustic emission generated by the partial discharge in gas-insulated-switchgear (GIS). A model is established to investigate the effects of the cylinder coil on the sensitivity, the bandwidth, and the detection limit. After that, the proposed sensor was modified based on the effects. The average sensitivity of the optimized acoustic emission (AE) optical fiber sensor is 32 dB higher than that of the conventional lead zirconate titanate (PZT) in the frequency range from 20 kHz to 100 kHz. Moreover, the experimental results show that the detectable partial discharge initial voltage for the proposed optical system is 17.1% lower than that for the PZT system, and the amplitude of the signal detected by the proposed optical system is 525% higher than that detected by the PZT system.

Optical interferometer acoustic sensors for GIS partial discharge detection are proposed in recent years. However, the stability of the sensing system for actual apparatus PD detection is less of a concern, especially for actual GIS. In this paper, an optical fiber acoustic sensing system based on Michelson interferometer for GIS PD detection was developed. And the influence mechanism of environmental noise on the stability of the sensing system was analyzed. And then, a method of phase tracking feedback to resist noise interference was proposed. The Michelson optical fiber interferometer with the phase feedback system worked as a high-pass filter. And the cut off frequency was 1.8 kHz in the design. Lastly, the antiinterference performance of the optical fiber interferometer was tested in an actual 126kV GIS. With the designed phase feedback control system, the stability was ensured for the on-site application of the optical interferometric acoustic sensing system.

Flashover plasma across an epoxy sulfur hexafluoride interface in gas insulated switchgear (GIS) may induce blockage of power cut. However, characteristics of flashover plasma across an epoxy sulfur hexafluoride interface under the operation temperature of GIS (80°C) were less discussed previously. In this work, a high voltage experiment setup was built to investigate the temperature effect on the surface flashover plasma. The voltage, current, acoustic and ultra-high frequency signals were obtained with different kind of sensors. The experiments indicate that the flashover voltage reduced 11.74% when temperature increased from 20°C to 80°C. The distributions of electric field, temperature and the gas density were also simulated. A particle-in-cell model including field electron emission and temperature was developed to discuss the temperature effect. From the simulation results, it can be concluded that at higher temperature, it is more likely to develop flashover across an epoxy sulfur hexafluoride interface initiated by field electron emission. This work will give a reference for evaluation and design of epoxy sulfur hexafluoride interface for high-voltage GIS applications.

In Saccharomyces cerevisiae, Sir proteins mediate heterochromatin epigenetic gene silencing. The assembly of silent heterochromatin requires histone deacetylation by Sir2, conformational change of SIR complexes, and followed by spreading of SIR complexes along the chromatin fiber to form extended silent heterochromatin domains. Sir2 couples histone deacetylation and NAD hydrolysis to generate an epigenetic metabolic small molecule, O-acetyl-ADP-ribose (AAR). Here, we demonstrate that AAR physically associates with Sir3 and that polySir3-AAR formation has a specific and essential role in the assembly of silent SIR-nucleosome pre-heterochromatin filaments. Furthermore, we show that AAR is capable of stabilizing binding of the Sir3 BAH domain to the Sir3 carboxyl-terminal region. Our data suggests that for the assembly of SIR-nucleosome pre-heterochromatin filament, the structural rearrangement of SIR-nucleosome is important and result in creating more stable interactions of Sir3, such as the inter-molecule Sir3-Sir3 interaction, and the Sir3-nucleosome interaction within the filaments. In conclusion, our results reveal the importance of AAR, indicating that it not only affects the conformational rearrangement of SIR complexes but also might function as a critical fine-tuning modulatory component of yeast silent SIR-nucleosome pre-heterochromatin by stabilizing the intermolecular interaction between Sir3 N- and C-terminal regions.

Optical fiber acoustic emission sensor was optimized to enhance the sensitivity of partial discharge detection in GIS. Amplitude of the signal detected by the proposed system was 525% higher than that of conventional system.

The pathophysiological changes in cells are mainly focusing on the ionic regulations like hyperpolarization, depolarization etc. The real-time monitoring of these changes in ionic behavior is one of the challenging areas in the biosensor field. A field-effect transistor (FET) based sensor system shows an exceptional advantage in noninvasive real-time monitoring of cellular changes. In this study, we monitored cell proliferation in real-time by using the FET biosensor. Cells were cultured on the FET sensing surface and the potential difference was monitored using the Electric-double-layer field-effect transistor (EDL-FET) biosensor system. Cell proliferation in the sensor surface was electrically measured as drain current change. The impedance measurement changes revealed the capacitive equivalent model of the FETs system. The most important factor in a cell-based system is to overcome the limited life span of cells in sensor platforms. This sensor platform was capable of monitoring cell growth and proliferation, compared with other conventional and current cell sensor platforms. Rapid electrical response corresponding to the cell growth and other functional changes associated with the cell can be used in many fields, including medicine, environmental monitoring and drug screening.

Weld lines are commonly present within injection-molded plastic components and generally reduce strength. In designing a plastic part, the designer can often vary the wall thicknesses, or move the gate locations to position the weld line, so that its structural loading is minimized. By altering such variables as melt temperature, mold temperature, and packing pressure, slight increases in weld-line integrity can be achieved. These approaches often do not increase the part strength or performance to an acceptable level, resulting in the exclusion of numerous applications for plastic conversion. This study investigated a hot runner system, sequential valve gates, and heat degree, to achieve economical methods for predicting weld-line properties. By calculating melt front temperatures with MoldFlow analysis, we can predict the strength of the weld line according to the definition of “heat degree”, which is the effective cross-sectional area of the melt front multiplied by the temperature gradient. An effective cross-sectional area of the melt front is defined as the area of the temperature above the melting point. In contrast to the test result, when the “sum of heat degree” is lower than 1150 mm2 °C for PA6 (Mitsubishi 1030J) and 500 mm2 °C for polypropylene (PP) (FCFC K1012), the molecules cannot bond adequately at the interface of the melt fronts. Therefore, the mechanical property declines significantly.

Triplophysa daochengensis sp. nov. is described from the Daocheng River, a northern tributary of the Jinsha River in Sichuan Province, China. The new species can be distinguished from its congeners by the following characters: body smooth and scales absent; lateral line complete; caudal peduncle compressed, depth unchanging; head length equal to caudal-peduncle length; lower jaw shovel-shaped; dorsal-fin origin anterior to pelvic-fin origin and closer to the tip of the snout than to the caudal-fin base, last unbranched ray hard; pelvic-fin tip not reaching anus; posterior chamber of gas bladder absent; intestine of spiral type with three winding coils.

It is not possible to clearly visualize how chromatin condenses to heterochromatin in vivo. However, in an in vitro system for Saccharomyces cerevisiae, the requirements for heterochromatin filament formation mirror those found in vivo. Here we report that the nucleosomes and the Sir2, Sir3 and Sir4 proteins, which are required for in vitro filament assembly, are also components of these filaments, confirming that the filaments are SIR-nucleosome filaments. We show the individual localization patterns of the Sir proteins on this SIR-nucleosome filament, and demonstrate that the metabolite, AAR, plays a specific and essential role in promoting the formation of this SIR-nucleosome filament.

Expression of OLE16 and OLE18, two oleosin isoforms in oil bodies of rice seeds, was suppressed by RNA interference. Electron microscopy revealed a few large, irregular oil clusters in 35S::ole16i transgenic seed cells, whereas accumulated oil bodies in 35S::ole18i transgenic seed cells were comparable to or slightly larger than those in wild-type seed cells. Large and irregular oil clusters were observed in cells of double mutant seeds. These unexpected differences observed in oil bodies of 35S::ole16i and 35S::ole18i transgenic seeds were further analyzed. In comparison to wild-type plants, OLE18 levels were reduced to approximately 40% when OLE16 was completely eliminated in 35S::ole16i transgenic plants. In contrast, OLE16 was reduced to only 80% of wild-type levels when OLE18 was completely eliminated in 35S::ole18i transgenic plants. While the triacylglycerol content of crude seed extracts of 35S::ole16i and 35S::ole18i transgenic seeds was reduced to approximately 60% and 80%, respectively, triacylglycerol in isolated oil bodies was respectively reduced to 45% and 80% in accordance with the reduction of their oleosin contents. Oil bodies isolated from both 35S::ole16i and 35S::ole18i transgenic seeds were found to be of comparable size and stability to those isolated from wild-type rice seeds, although they were merely sheltered by a single oleosin isoform. The drastic difference between the triacylglycerol contents of crude seed extracts and isolated oil bodies from 35S::ole16i transgenic plants could be attributed to the presence of large, unstable oil clusters that were sheltered by insufficient amounts of oleosin and therefore could not be isolated together with stable oil bodies.