Mouse Models of Sjögren’s Syndrome with Ocular Surface Disease

Sjögren’s syndrome (SS) is a systemic rheumatic disease that predominantly affects salivary and lacrimal glands resulting in oral and ocular dryness, respectively, referred to as sicca symptoms. The clinical presentation of ocular dryness includes keratoconjunctivitis sicca (KCS), resulting from the inflammatory damage to the ocular surface tissues of cornea and conjunctiva. The diagnostic evaluation of KCS is a critical component of the classification criteria used by clinicians worldwide to confirm SS diagnosis. Therapeutic management of SS requires both topical and systemic treatments. Several mouse models of SS have contributed to our current understanding of immunopathologic mechanisms underlying the disease. This information also helps develop novel therapeutic interventions. Although these models address glandular aspects of SS pathology, their impact on ocular surface tissues is addressed only in a few models such as thrombospondin (TSP)-1 deficient, C57BL/6.NOD.Aec1Aec2, NOD.H2^b, NOD.Aire KO, and IL-2Rα (CD25) KO mice. While corneal and/or conjunctival damage is reported in most of these models, the characteristic SS specific autoantibodies are only reported in the TSP-1 deficient mouse model, which is also validated as a preclinical model. This review summarizes valuable insights provided by investigations on the ocular spectrum of the SS pathology in these models.     

Error analysis to minimize cross-axis couplings in 6-DOF motion systems with a single moving part

In multi-axis motion control, cross-axis couplings cause error force and position disturbances in an axis when a desired motion is generated along another axis. Different from the parasitic errors that result from the imperfections of the mechanical bearings and reference surfaces, cross-axis perturbations are caused by errors that occur both statically (geometrical errors) and dynamically (in the transient responses) and are more prevalent in air-bearing and magnetic-levitation (maglev) stages. The parasitic errors are heavily dependent on the sizes of the stage's mechanical components, while the cross-axis perturbations depend significantly on the mover's speed and acceleration. For stages using permanent magnets (PMs) and Lorentz coils, the causes of off-axis forces include 1) errors in the coil turns' straightness, perpendicularity, and parallelism of the motor axes, and 2) errors in the local magnetizations and PMs' fringing effects. The purpose of this paper is to analyze the topologies of 6-degree-of-freedom (6-DOF) single-moving-part stages to minimize cross-axis couplings. The outcome is a stage configuration with reduced couplings and cross-axis perturbations. This is supported by experimental results performed on a newly developed 6-DOF maglev laser-interferometer stage. Its achieved root-mean-square (rms) positioning noise and minimum step size in XY are 3 nm and 10 nm, respectively. Its achieved resolution in out-of-plane rotations is 0.1 μrad. In addition to the analysis supported by these results, this paper introduces a new measure to represent cross-axis perturbations and to compare the effects of couplings in multi-axis positioning. This measure is entitled the cross-coupling quantity (CCQ) and calculated from the displacement of the stage in the axis of interest, the peak time of the response, and the peak-to-peak (p-p) error in the perturbed axis.     

Ti6Al4V钛合金表面Al2O3颗粒改性微弧氧化涂层制备及性能

微弧氧化技术是一门新的表面处理技术,在很多领域有着广泛的应用前景,但其结构受限于电解液成分。本文通过在磷酸盐电解液中加入Al2O3陶瓷颗粒,使得在Ti6Al4V钛合金表面的微弧氧化涂层结构和性能得到改性。涂层的结构和性能通过扫描电镜和XRD衍射仪进行表征和测试,涂层的抗高温氧化性能和热震性能通过高温热循环氧化试验和热震试验进行测试。结果表明,通过在电解液中添加Al2O3陶瓷颗粒,涂层由Al2TiO5 and TiO2组成,涂层更为致密,表现出更为优异的抗高温氧化和热震性能。电解液中游动的Al2O3陶瓷颗粒在微弧氧化过程中被吸入到样品表面并进入涂层,涂层的结构和性能得到改性。     

Comparison in composite performance after thermooxidative aging of injection molded polyamide 6 with glass fiber,talc, and a sustainable biocarbon filler

Degradation is an unavoidable part of a material's life making it important to both monitor and control the aging behavior of plastics. This study compares thermooxidative degraded composites of a novel bio-based and sustainable filler, Biocarbon (MBc), against that of traditional and commercially available fillers (glass fiber and talc) used in the automotive industry. The influence of thermooxidative degradation on the composites was studied under accelerated heat aging for 1000 h at 140°C. The mechanical properties of the composites were evaluated using notched Izod impact as well as both tensile and flexural tests. Morphological structure of the composites was investigated using a scanning electron microscopy. Dynamic mechanical analysis and differential scanning calorimetry were used to evaluate the physical transitions both before and after aging. The glass-filled composites displayed the best performance; while, both the talc and biocarbon composites possessed similar strength and ductility performances. Advantageously, the biocarbon composites experienced an 11% reduction in density as compared to talc-filled composites with similar weight content. After aging, all composites exhibited reduced tensile and flexural strengths ranging from 5 to 67% partly due to chain scission. Whereas, the modulus of all composites increased with a range of 1–24% due to an annealing effect. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48618.     

Biogas upgrading using ionic liquid [Bmim][PF6] followed by thermal-plasma-assisted renewable hydrogen and solid carbon production

The use of hydrogen as clean energy has attracted significant attention because conventional industrial hydrogen production processes show negative environmental impact, require intensive energy, and/or are dependent on natural gas. The main objective of this study is to develop an innovative and environment-friendly hydrogen production process utilizing biogas as an alternative to natural gas. Ionic liquid [Bmim][PF₆] shows high potential for the replacement of aqueous amine solutions for CO₂ absorption and are employed for biogas upgrading, while thermal plasma (TP), which is beneficial for converting electrical energy to chemical energy, is employed for the simultaneous production of clean “turquoise” hydrogen and solid carbon. In addition, an intercooler is used to improve CO₂ removal in the absorber. Heat and power integration are employed to enhance the performance of the upgrading process and thermal-plasma-assisted hydrogen production. All simulations were conducted using Aspen Plus V10.0 software. The simulated results show that the solid carbon production from biomethane increases compared to that in the proposed base case. The savings in both the heater used to preheat the TP reactor and the third flash drum are 100%, while the saving in power consumption in the compression section is 62.0%. Furthermore, sensitivity is investigated to determine the effect of biomethane composition on the performance of the proposed configuration.     

基于动态策略的移动警务终端安全管控系统的设计与实现

对移动警务安全接入平台中的终端设备的安全防护问题进行了研究,提出并研制了一种基于动态策略的移动警务终端安全管控系统,整个系统由客户端、前置服务端和内网服务端组成,前置服务端和内网服务端分别部署在前置区和公安内网,客户端部署在移动终端设备上,确保在移动接入区和公安内网区有效进行物理隔离的前提下,将系统制定的各种安全策略规则下发到客户端执行,规范用户对移动终端的本地软硬件资源和网络资源的使用,实现安全威胁检测、防护及预警,对移动终端用户的违规访问、操作行为进行全面监测和上报,实现终端设备安全和行为的统一管理.     

Approaches to Evaluate the Impact of a Small-Molecule Binder to a Noncatalytic Site of the Proteasome

Proteasome activity is crucial for cell survival and proliferation. In recent years, small molecules have been discovered that can affect the catalytic activity of the proteasome. Rather than targeting the active sites of the proteasome, it might be possible to affect ubiquitin-dependent degradation of proteins by limiting the association of the 19S regulatory particle (19S RP) with the 20S core particle (20S CP) of the proteasome. We recently described the discovery of TXS-8, a peptoid that binds to Rpn-6. Rpn-6 is a proteasome-associated protein that makes critical contacts with the 19S RP and the 20S CP. Herein, we present a general workflow to evaluate the impact of a small-molecule binder on proteasome activity by using TXS-8 as an example. This workflow contains three steps in which specific probes or overexpressed proteins in cells are used to determine whether the hydrolysis activity of the proteasome is affected. Although, in our case, TXS-8 did not affect proteasome activity, our workflow is highly amenable to studying a variety of small-molecule–proteasome subunit interactions.     

Future changes in wind energy resource over the Northwest Passage based on the CMIP6 climate projections

The preferential use of renewable energy sources such as wind power has been proposed as one of the most effective strategies in reducing greenhouse gas emissions in the energy sector. However, wind energy resources are vulnerable to climate change, which might have a huge impact on the area under consideration. In this research, we used the wind speed data obtained from the seven coupled global climate models in the Coupled Model Intercomparison Project Phase 6 (CMIP6) to quantitatively analyze the differences in wind energy resource (WER) between the future and the historical period, geared toward understanding the impact of climate change on wind energy sources. Relevant results show that the future WER would decreases below 20% in the region south of the Northwest Passage, while would significantly increase in the north region of 72°N (specifically in the Beaufort Sea). Further, reports predict that by the end of the 21st century, if no interventions are made to mitigate greenhouse gas emissions, the northern region's WER would increase even more with some grid points exceeding 30% and have a significant growth trend, but at the same time the intra‐annual variability in these region would also increase significantly with some grid points exceeding 140% of that in the historical period. Moreover, the maximum wind speed values would encounter a noteworthy increase of up to 20%, which will bring great challenge to the development of wind energy in these region. Although the current models still have great uncertainties in the future climate prediction, our work still has certain guiding significance for the future development of wind energy over the Northwest Passage.     

Effect of moisture and filler content on the structural,thermal and dielectric properties of polyamide‐6/boehmite alumina nanocomposites

Polyamide‐6 (PA‐6)/boehmite alumina (BA) nanocomposites were prepared via direct melt compounding. Structural, thermal and dielectric properties of ‘as‐received’ (including moisture) and ‘dried’ (thermally treated) specimens were examined. The BA nanofiller was homogeneously dispersed in the PA‐6 matrix. XRD and FTIR revealed that crystallization of PA‐6 in the γ phase was favoured over α phase with increasing BA content. The crystallinity index (CI) and the percentage of α and γ phases were also evaluated. Dried specimens exhibited a lower CI than as‐received specimens while the CI decreased with the addition of filler. Broadband dielectric spectroscopy revealed the presence of γ, β and α relaxations, the Maxwell–Wagner–Sillars effect and the contribution of conductivity relaxation in the as‐received samples. The drying procedure unmasked a double feature of both β and α modes. The results of the complementary techniques were analysed and the effects of moisture and/or the incorporation of BA nanofiller on the microstructure of the PA‐6 matrix are disclosed. © 2019 Society of Chemical Industry