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An on-axis deflectometric microscope system (ODMS) is proposed for the microscopic surface measurement with high accuracy and a large slope dynamic range. To reduce the geometry sensitivity, a beam splitter is employed to build the coaxial configuration among the illumination screen, camera, and tested sample, which facilitates the calibration of system geometrical parameters. Due to the small working distance, the system model miscalibration in the model-ray-tracing-based “null” testing could cause obvious geometrical aberrations. In this paper, the geometrical aberrations due to the system model miscalibration are analyzed, and the corresponding calibration method based on computer-aided reverse optimization is applied to achieve accurate measurement. In addition, the systematic error introduced by the system components in the ODMS are also discussed. Both the simulation and experiment have been carried out to demonstrate the feasibility and high accuracy of the proposed measurement method. The proposed system is compact in structure, large in measurable slope range, and high in spatial resolution, providing a viable metrological tool for the microscopic testing of various freeform surfaces, microstructural elements, and micro-devices.

Alkyl polyglycoside (APG) is a green surfactant with excellent interfacial activity, emulsified ability, foaming performance and wettability, which has great potential in enhancing heavy oil recovery at high-temperature and high-salinity condition. In this paper, surface tension, interfacial tension, emulsifying ability, emulsion stability and emulsified oil droplet size were investigated for APG. Besides, the effect of temperature and salinity on interfacial activity and emulsification properties of APG was also studied. The results showed that APG had excellent interfacial activity and emulsification property among all these surfactants. Besides, the interfacial activity and emulsification properties of APG almost did not decrease, and even got better along with the increasing temperature or salinity, while those of other surfactants became worse in different degree. The incremental oil recovery by using APG at 90 °C and the salinity of 30 g/L can reach to 10.1% which is nearly two times higher than that of common EOR surfactants. These results indicated that APG is an efficient surfactant for enhancing heavy oil recovery at high-temperature and high-salinity condition.

Numerous studies have explored the therapeutic potential of microRNA (miR) in myocardial infarction (MI) treatment. This study focuses on the role of miR-322-5p in MI, particularly in its regulatory interaction with B-cell translocation gene 2 (BTG2).

It is significant to develop functional materials with high selectivity, high adsorption capacity and easy separation to reduce thallium (Tl) pollution caused by human activities. Polysaccharide-based cyanide-bridged bimetallic coordination polymers (PCBPs) were developed for the removal of Tl(I) and Tl(Ⅲ) simultaneously, and the effects of lists of conditions on the removal of Tl showed that the maximum adsorption rate of Tl reached 98.3 % after 180 min. Meanwhile, the stable adsorption efficiency of Tl could be maintained in a wide range of pH. Moreover, even in the interfering system where high-intensity cations and total organic matter coexist, PCBPs still showed excellent Tl removal efficiency. Notably, the amphoteric structure of PCBPs provided many chemical chelation sites, significantly improving the adsorption capacity of PCBPs for Tl. Importantly, XRD, SEM, TEM, BET, and magnetization tests show that PCBP has a large pore and specific surface area, stable structure, and recyclable magnetic characteristics conducive to the adsorption of thallium. More importantly, the π-π conjugation and chelation of the above functional groups with Tl(I) and Tl(Ⅲ) were well confirmed by FT-IR and XPS for their adsorption mechanism. What is more, the adsorption isotherm and kinetics agreed with the Freundlich model and the pseudo-second-order model, respectively, indicating that the adsorption of Tl was a multi-layer chemical adsorption process. Besides, the Gibbs free energy was negative, indicating that the adsorption process of Tl was spontaneous. Therefore, the polysaccharide-loaded ferric ferrocyanide coordination polymer exhibited high-efficiency and selectivity removal of Tl(I) and Tl(Ⅲ), which would provide technical support and theoretical guidance for the treatment of thallium-containing wastewater.

Astrocyte-microglial interaction plays a crucial role in brain injury-associated neuroinflammation. Our previous data illustrated that astrocytes secrete microRNA, leading to anti-inflammatory effects on microglia. Long non-codingRNAs participate in neuroinflammation regulation post traumatic brain injury. However, the effect of astrocytes on microglial phenotype via long non-codingRNAs and the underlying molecular mechanisms remain elusive. We used long non-codingRNA sequencing on murine astrocytes and found that exosomal long non-codingRNA 4933431K23Rik attenuated traumatic brain injury-induced microglial activation in vitroand in vivoand ameliorated cognitive function deficiency. Furthermore, microRNA and messengerRNA sequencing together with binding prediction illustrated that exosomal long non-codingRNA 4933431K23Rik up-regulates E2F7 and TFAP2C expression by sponging miR-10a-5p. Additionally, E2F7 and TFAP2C, as transcription factors, regulated microglial Smad7 expression. Using Cx3cr1-Smad7 overexpression of adeno-associated virus, microglia specifically overexpressed Smad7 in the attenuation of neuroinflammation, resulting in less cognitive deficiency post traumatic brain injury. Mechanically, overexpressed Smad7 physically binds to IκBα and inhibits its ubiquitination, preventing NF-κB signaling activation. The Smad7 activator asiaticoside alleviates neuroinflammation and protects neuronal function in traumatic brain injury mice. This study revealed that an exosomal long non-codingRNA from astrocytes attenuates microglial activation post traumatic brain injury by up-regulating Smad7, providing a potential therapeutic target.

Cognitive flexibility enables effective switching between mental processes to generate appropriate responses. Cholinergic neurons (CNs) within the pedunculopontine nucleus (PPN) are associated with many functions, but their contribution to cognitive flexibility remains poorly understood. Here we measure PPN cholinergic activities using calcium indicators during the attentional set-shifting task. We find that PPN CNs exhibit increasing activities correlated with rewards during each stage and error trials in reversal stages, indicating sensitivity to rule switching. Inhibition of PPN cholinergic activity selectively impairs reversal learning, which improves with PPN CN activation. Activation of PPN CNs projecting to the substantia nigra pars compacta, mediodorsal thalamus, and parafascicular nucleus in a time-locked manner with reward improves reversal learning. Therefore, PPN CNs may encode not only reward signals but also the information of changing reward contingency that contributes to guiding reversal learning through output projections to multiple nuclei that participate in flexibility.

We have shown previously, that mice lacking tumor necrosis factor-α (TNF-α) receptor 1 (TNFR1) exhibit greater hippocampal neurodegeneration, suggesting that TNFR1 may be protective in kainic acid (KA)-induced neurotoxicity. Here, we aim to clarify the role of TNF-α in neurodegenerative disorders and to elucidate its potential signaling pathways. TNF-α knockout (KO) mice and wild-type (WT) mice were treated with KA intranasally and, seizure severity measures obtained, Behavioral tests, including Elevated Plus-Maze™, open-field, Y-maze were also performed. Five days following KA treatment, immunohistochemical methods were used to assess neuronal degeneration and glial activation. The production of nitric oxide (NO) and the expression of nuclear factor kappaB (NF-αB) and AKT in the hippocampus were also measured. Compared with WT mice, TNF-α KO mice were more susceptibile to KA-induced neurotoxicity, as demonstrated by more severe seizures, measurable behavior changes, greater neuronal degeneration in hippocampus, elevated glial activation and NO production. Additionally, KA-treatment up-regulated the expression of NFκB in TNF-α KO mice to a greater degree than in KA-treated WT mice. We conclude that TNF-α deficiency adversely influences KAinduced neurotoxicity and that TNF-α may play a protective role in KA-induced neurotoxicity via the down-regulation of NFκB signaling pathway.

In this work, 3-dimensional flower-like Y2O3:Eu3+ microstructures were synthesized through a facile route using simple hydrothermal reaction and sequentially calcinations without templates or matrix. The flower-like micro-architectures are self-assembled by nanosheets with thickness of about 50 nm and diameter about 3-5 μm, which were verified by the field-emission electron microscopy (FESEM) and transmission electron microscope (TEM). The as-synthesized Y2O3:Eu3+ samples show a strong red emission due to 5D0-7F2 transition (612nm), suggesting potential applications in red phosphors.

Abstract: This paper presented a novel wide-area nonlinear excitation control strategy for multi-machine power systems. A simple and effective model transformation method was proposed for the system’s mathematical model in the COI (center of inertia) coordinate system. The system was transformed to an uncertain linear one where deviation of generator terminal voltage became one of the new state variables. Then a wide-area nonlinear robust voltage controller was designed utilizing a LMI (linear matrix inequality) based robust control theory. The proposed controller does not rely on any preselected system operating point, adapts to variations of network parameters and system operation conditions, and assures regulation accuracy of generator terminal voltages. Neither rotor angle nor any variable’s differentiation needs to be measured for the proposed controller, and only terminal voltages, rotor speeds, active and reactive power outputs of generators are required. In addition, the proposed controller not only takes into account time delays of remote signals, but also eliminates the effect of wide-area information’s incompleteness when not all generators are equipped with PMU (phase measurement unit). Detailed tests were conducted by PSCAD/EMTDC for a three-machine and four-machine power systems respectively, and simulation results illustrate high performance of the proposed controller.

Tigecycline serves as one of the antibiotics of last resort to treat multidrug-resistant (including carbapenem-resistant) pathogens. However, the recently emerged plasmid-mediated tigecycline resistance mechanism, Tet(X), challenges the clinical efficacy of this class of antibiotics. In this study, we detected 180 tet(X)-harboring Acinetobacterisolates (8.9%, n= 180) from 2,018 samples collected from avian farms and adjacent environments in China.

We identified fosA3at a rate of 2.6% in 310 Salmonellaisolates from food animals in Guangdong province, China. The fosA3gene was genetically linked to diverse antibiotic resistance genes (ARGs), including mcr-1, blaCTX-M-14/55, oqxAB, and rmtB. These gene combinations were embedded in heterogeneous fosA3-containing multidrug resistance regions on the transferable ST3-IncHI2 and F33:A−:B− plasmids and the chromosome.

We reported the complete nucleotide sequence of a tet(X4)-carrying plasmid, pSTB20-1T, from a tigecycline-resistant Escherichia coliisolate in China. Sequence analysis indicated that pSTB20-1T contains a hybrid plasmid backbone and a tet(X4)-containing multidrug resistance region, likely originated through recombination of multiple plasmids. tet(X4) was flanked by two ISCR2, which may be responsible for tet(X4) mobilization.