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Okanin attenuated cognitive impairment in BCCAO mice. Okanin inhibited microglial activation, decreased NLRP3 inflammasome activation and increased miR-7 expression in vivo and in vitro, and inhibited microglia-induced neuronal injury.

Ischemic stroke is a leading cause of death and disability worldwide. Post-ischemia, microglia respond immediately to the alternations in neuronal activity and mediate inflammation. Toll-like receptor 4 (TLR4) plays a key role in this phenomenon. To explore the effect of loureirin C, an effective compound from Chinese Dragon's blood, on ischemic stroke, Sprague-Dawley rats were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) with/without intragastric administration of loureirin C (7, 14, and 28 mg/kg). Loureirin C alleviated MCAO/R-induced brain impairment evaluated by neurological scores (p 0.001), brain water content (p 0.001), and cerebral infarct volume (p = 0.001). The neuroprotective (p 0.001) and inhibitory effects on microglial activation (p 0.001) of loureirin C were revealed by immunofluorescence. Rescue studies with TLR4 overexpression in BV-2 microglia showed that the antiinflammatory effect of loureirin C was attributable to the inhibition of TLR4 protein expression. Moreover, co-immunoprecipitation assays showed that the binding of Triad3A, an E3 ubiquitin ligase of TLR4, was increased by loureirin C (p = 0.003). Our study demonstrates that loureirin C could be a promising therapeutic agent for the management of ischemic stroke by inhibiting microglial activation, potentially by Triad3A-mediated promotion of TLR4 ubiquitination and degradation.

Cognitive impairment is the main clinical feature following stroke, and microglia-mediated inflammatory response is a major contributor to it.

Ion mobility analysis is a well-known analytical technique for identifying gas-phase compounds in fast-response gas-monitoring systems. However, the conventional plasma discharge system is bulky, operates at a high temperature, and inappropriate for volatile organic compounds (VOCs) concentration detection. Therefore, we report a machine learning (ML)-enhanced ion mobility analyzer with a triboelectric-based ionizer, which offers good ion mobility selectivity and VOC recognition ability with a small-sized device and non-strict operating environment. Based on the charge accumulation mechanism, a multi-switched manipulation triboelectric nanogenerator (SM-TENG) can provide a direct current (DC) bias at the order of a few hundred, which can be further leveraged as the power source to obtain a unique and repeatable discharge characteristic of different VOCs, and their mixtures, with a special tip-plate electrode configuration. Aiming to tackle the grand challenge in the detection of multiple VOCs, the ML-enhanced ion mobility analysis method was successfully demonstrated by extracting specific features automatically from ion mobility spectrometry data with ML algorithms, which significantly enhance the detection ability of the SM-TENG based VOC analyzer, showing a portable real-time VOC monitoring solution with rapid response and low power consumption for future internet of things based environmental monitoring applications.

Engineering of graphite@Si/carbon composites is considered as an effective strategy to surmount the shortcomings of the low conductivity and large volume expansion of bare Si anode materials for lithium-ion batteries. Nevertheless, their applications in high-performance electric vehicles are still challenging owing to their limited accessible capacity. Herein, SiO2 as an active additive was introduced to improve the capacity of graphite@Si/carbon composites. Two different composites, graphite@Si sequentially embedded in SiO2 and carbon layers (G@Si/SiO2 layer/C) and encapsulated in a carbon conformally coated tiny SiO2 nanoparticle matrix (G@Si/SiO2 NPs/C), were well-designed. Both the Si/C composites exhibit a longer cycle life than the graphite@Si/C due to the unique double protective sheath of inert components (Li2O and Li4SiO4) and carbon. The former was formed during the first lithium insertion of SiO2. Specifically, the G@Si/SiO2 NPs/C shows a high specific capacity (607 mA h g−1), exceptional cycling stability (92% retention after 800 cycles at a 0.5 A g−1) and promising rate capability. The remarkable performances benefit from the porous three-dimensional network structure constructed by an amorphous carbon matrix shell and a graphite core, which well disperse and support Si and SiO2, thus improving their electrochemical activity, alleviating the volume change and increasing the Li-ion diffusion effectively.

We propose a plasma-activated direct bonding process at low temperatures (≤200 °C) to form heterostructures between single-crystalline SiC and conventional Si-based substrates (SiO2, Si, and glass) without any interlayers. Surface activation was performed via an inductively coupled O2 plasma for 60 s with a lower bombardment damage position. The SiC surfaces were much more hydrophilic after activation, and the generation of defect states was suppressed. Consequently, void-free and robust bonding interfaces of SiC/SiO2, SiC/Si and SiC/glass were successfully achieved. There were no carbon-enriched layers across the bonding interfaces, which could improve the electrical properties of SiC-based devices. Additionally, the bonding interface of SiC/glass exhibited excellent optical transparency, and interfacial corrosion resistance was confirmed via immersion tests in biological solutions. This bonding method provides a feasible route towards industry-compatible heterogeneous integration of single-crystalline bulk SiC onto Si-based platforms for electronic, optical, mechanical, and biomedical applications.

As one of the most effective surface-enhanced infrared absorption (SEIRA) techniques, metal-insulator-metal structured metamaterial perfect absorbers possess an ultrahigh sensitivity and selectivity in molecular infrared fingerprint detection. However, most of the localized electromagnetic fields (i.e., hotspots) are confined in the dielectric layer, hindering the interaction between analytes and hotspots. By replacing the dielectric layer with the nanofluidic channel, we develop a sapphire (Al2O3)-based mid-infrared (MIR) hybrid nanofluidic-SEIRA (HN-SEIRA) platform for liquid sensors with the aid of a low-temperature interfacial heterogeneous sapphire wafer direct bonding technique. The robust atomic bonding interface is confirmed by transmission electron microscope observation. We also establish a design methodology for the HN-SEIRA sensor using coupled-mode theory to carry out the loss engineering and experimentally validate its feasibility through the accurate nanogap control. Thanks to the capillary force, liquid analytes can be driven into sensing hotspots without external actuation systems. Besides, we demonstrate an in situ real-time dynamic monitoring process for the acetone molecular diffusion in deionized water. A small concentration change of 0.29% is distinguished and an ultrahigh sensitivity (0.8364 pmol-1 %) is achieved. With the aid of IR fingerprint absorption, our HN-SEIRA platform brings the selectivity of liquid molecules with similar refractive indexes. It also resolves water absorption issues in traditional IR liquid sensors thanks to the sub-nm long light path. Considering the wide transparency window of Al2O3 in MIR (up to 5.2 μm), the HN-SEIRA platform covers more IR absorption range for liquid sensing compared to fused glass commonly used in micro/nanofluidics. Leveraging the aforementioned advantages, our work provides insights into developing a MIR real-time liquid sensing platform with intrinsic IR fingerprint selectivity, label-free ultrahigh sensitivity, and ultralow analyte volume, demonstrating a way toward quantitative molecule identification and dynamic analysis for the chemical and biological reaction processes.

We developed a plasma activation process using a gas mixture of O2/NH3/H2O for direct bonding, which realized the combination of bulk aluminum oxide (Al2O3) and yttria-stabilized cubic zirconia (YSZ) without interlayers for the first time. The bonding could withstand multiple mechanical grinding and polishing processes and exhibited sufficient bonding strength for device micro/nanofabication. A nanoscale, sharp, and layered crystalline bonding interface with fewer grain boundaries was confirmed by transmission electron microscopy. The interfacial structure is well-suited for superior performance in high dielectric constant metal–oxide–semiconductor field-effect transistors. Moreover, this bonding method is universal for the fabrication of Al2O3/SiO2 and YSZ/SiO2 heterostructures.

Pterostilbene, a methylated stilbene derived from many plant foods, has significant anti-inflammatory activity. Meanwhile, vascular dementia (VaD) is the second most common subtype of dementia, in which inflammation is one of the major pathogenic contributors. However, the protective effect of pterostilbene on VaD is not well understood. In this work, we investigated the effect of pterostilbene on VaD and explored its underlying mechanisms using in vivo and in vitro models. Y-maze and Morris water maze tests showed pterostilbene-attenuated cognitive impairment in mice with bilateral common carotid artery occlusion (BCCAO). The hippocampal neuronal death and microglial activation in BCCAO mice were also reduced by pterostilbene treatment. Further, pterostilbene inhibited the expression of TLR4 and downstream inflammatory cytokines in these mice, with similar results observed in an oxygen-glucose deprivation and reperfusion (OGD/R) BV-2 cell model. In addition, its anti-inflammatory effect on OGD/R BV-2 cells was partially blocked by TLR4 overexpression. Moreover, Triad3A-TLR4 interactions were increased by pterostilbene following enhanced ubiquitination and degradation of TLR4, and the inhibitory effect of pterostilbene on inflammation was blocked by Triad3A knockdown in OGD/R-stimulated BV-2 cells. Together, these results reveal that pterostilbene could reduce vascular cognitive impairment and that Triad3A-mediated TLR4 degradation might be the key target.

Ischemic stroke is a severe neurological disease without known effective therapy. Microglia-mediated neuroinflammation plays an important role in ischemic stroke. Therefore, finding a safe and effective microglial activation inhibitor might lead to an effective therapeutic strategy against ischemic stroke. In this project, our goal was to explore both the mechanism and effect of pterostilbene in MCAO/R rats. The potential effect of pterostilbene on ischemic stroke was tested using MCAO/R rats and its effect on microglial activation was tested in LPS-stimulated BV-2 cells. In vivo, pterostilbene decreased the neurological scores, brain water content and infarct volume in MCAO/R rats. Pterostilbene increased the number of mature neurons, decreased the number of activated microglia, and reduced iNOS and IL-1β mRNA expression. Pterostilbene inhibited phosphorylated-IκBα expression, thus promoting IκBα expression and inhibiting ROS overexpression. In vitro, pterostilbene inhibited the expression of inflammatory cytokines and suppressed NAPDH activity as well as activation of both the NF-κB pathway and ROS production. To our knowledge, our study is the first to demonstrate that pterostilbene-mediated alleviation of cerebral ischemia and reperfusion injury in rats may be correlated with the inhibition of the ROS/NF-κB-mediated inflammatory pathway in microglia, indicating the potential for the use of pterostilbene as a candidate therapeutic compound for ischemic stroke.

A continuous layer of Ni3Sn4 compounds was formed at the Sn-37Pb solder/Ni interface in ball grid array solder joints after reflowing. Au0.5Ni0.5Sn4 compounds were formed between Sn-37Pb solder and Ni3Sn4 layer during thermal shock between -196 °C and 150 °C, and the solder/Ni interface exhibited a duplex structure of Au0.5Ni0.5Sn4 and Ni3Sn4 layers only after 300 cycles. The growth of Ni3Sn4 and Au0.5Ni0.5Sn4 under thermal shock was significantly enhanced by high thermal stresses generated from the thermal expansion mismatch between Sn-37Pb solder and Ni, and the extreme temperature change (ΔT = 346 °C). The fast growth and high stiffness of Ni3Sn4 and Au0.5Ni0.5Sn4, as well as the thermal expansion mismatch between Ni3Sn4 and Au0.5Ni0.5Sn4, and the extreme temperature change resulted in the brittle fracture of Sn-37Pb solder joints at the Ni3Sn4/Au0.5Ni0.5Sn4 interface under extreme temperature changes.

Single-crystalline silicon carbide is an attractive material for power electronics. However, it is difficult to achieve the direct bonding of SiC to conventional Si-based materials (e.g., Si, SiO2, and glass) due to the large mismatch in coefficients of thermal expansion and lattice constants. To solve the bottleneck, we present a facile direct bonding method using vacuum ultraviolet (VUV) surface irradiation for a robust combination of SiC to Si, SiO2, and glass at low temperatures (≤200 °C). The mechanisms behind the VUV-irradiated bonding of SiC to Si-based materials were also investigated. According to surface characterizations, VUV irradiation can lead to smooth and hydrophilic surfaces, which are beneficial for direct bonding in humid air. The tight and defect-free SiC/Si, SiC/SiO2 and SiC/glass bonding interfaces were confirmed by transmission electron microscopy. In particular, the enriched carbon transition layers were formed on the side of silicon carbide because of the oxidation and sputtering of Si atoms during VUV irradiation. This will possibly improve the bonding interfaces and contribute to the enhanced bonding strengths. Moreover, the SiC/glass bonded pair exhibited relatively high optical transparency in the UV–Vis range. Therefore, the direct bonding of single-crystalline SiC and heterostructure Si-based materials offers great potentials for high-performance power electronics, as well as micro/nanofluidic devices.

Wafer bonding technology is one of the most effective methods for high-quality thin-film transfer onto different substrates combined with ion implantation processes, laser irradiation, and the removal of the sacrificial layers. In this review, we systematically summarize and introduce applications of the thin films obtained by wafer bonding technology in the fields of electronics, optical devices, on-chip integrated mid-infrared sensors, and wearable sensors. The fabrication of silicon-on-insulator (SOI) wafers based on the Smart CutTM process, heterogeneous integrations of wide-bandgap semiconductors, infrared materials, and electro-optical crystals via wafer bonding technology for thin-film transfer are orderly presented. Furthermore, device design and fabrication progress based on the platforms mentioned above is highlighted in this work. They demonstrate that the transferred films can satisfy high-performance power electronics, molecular sensors, and high-speed modulators for the next generation applications beyond 5G. Moreover, flexible composite structures prepared by the wafer bonding and de-bonding methods towards wearable electronics are reported. Finally, the outlooks and conclusions about the further development of heterogeneous structures that need to be achieved by the wafer bonding technology are discussed.

Lithium niobate (LiNbO 3 ) is one of the most important multifunctional materials, which possesses excellent electro-optic and piezoelectric properties, as well as high transmittance in the mid-infrared (mid-IR) wavelength range. In this work, we developed a wet sequential plasma activated method for the heterogeneous direct bonding of single-crystal LiNbO 3 and Si with a nanometer-scale (∼6.4 nm) interface. Both surface and interface characterizations are used for the exploration of the bonding mechanism. For the first time, atomic structures of the LiNbO 3 /Si direct bonding interface have been disclosed. Leveraging this direct bonding method, we creatively integrate the metasurface into the LiNbO 3 -based nanofluidics for wavelength-dependent imaging. Because of the accurate nanogap control between the nanoantenna and metal reflector, the quadrupole resonance can be well excited. Therefore, the mid-IR imaging with ultrahigh contrast has been achieved in the wavelength of $2.68\ \mu \mathrm{m},\ 3.16\ \mu \mathrm{m}$ , and $3.61\ \mu\mathrm{m}$ . Moreover, since the hot spots are completely exposed in the nanochamber, which can be filled with various types of liquids. More images can be designed and presented based on the light-matter interaction and changes of refractive index. Therefore, this hybrid LiNbO 3 -based nanofluidics has great potential in the applications of switchable optical devices and information encryption.

In the present study, effect of pterostilbene on β-amyloid 1-42 (AβThe behavior results show that pterostilbene alleviated AβThe present study reports that pterostilbene alleviated Aβ

Low-temperature direct bonding is an effective method for joining two dissimilar materials into one composite. In this paper, we developed a universal method for fabricating single-crystalline SiC on Si, SiO2, and glass substrates via vacuum ultraviolet/ozone (VUV/O3) activated direct bonding at 200 °C. Our studies showed that VUV irradiation could lead to hydrophilic and smooth surfaces to be bonded. TEM observations confirmed that the transition layers of SiC/Si, SiC/SiO2, and SiC/glass direct bonded pairs were only nanoscale, which was beneficial for the miniaturization of power devices. On the basis of X-ray photoelectron spectroscopy (XPS) elemental depth profiles analysis, we also demonstrated that the enriched carbon layers at the bonding interfaces were originated from the SiC substrates during the VUV treatment. Additionally, the bonding mechanism was discussed combining all the experimental investigations.

Lithium niobate (LiNbO3) crystal has been widely used in integrating optical and acoustic devices. However, direct bonding of LiNbO3 to Si-based materials is still a challenge due to the large coefficient of thermal expansion mismatches. In this paper, strong bonding strength of the LiNbO3/glass pair was obtained via the optimized O2 plasma activation followed by N2 plasma treatment. After the pre-bonding was accomplished at room temperature, the bonded pair was annealed at 150 °C for 12 h. A defect-free and tight bonding interface was confirmed by the scanning electron microscopy and transmission electron microscopy. Based on atomic force microscopy, water contact angle and X-ray photoelectron spectroscopy characterizations, both LiNbO3 and glass surfaces became smoother and more hydrophilic due to the densities of OH and N-related groups increased. Additionally, combined with the bonding strength obtained via different plasma activated processes, we demonstrated that the mechanism of the enhanced bonding strength could be attributed to N-related covalent bonds formed across the bonding interface. Furthermore, the excellent optical transmittance of LiNbO3/glass bonded pairs indicated this facile bonding process can meet the demand of high-performance glass-on-LiNbO3 devices.

Low-temperature direct bonding is a promising method to integrate two or more dissimilar materials into one composite without large thermal stresses. In this paper, we describe a bonding process for silicon and quartz glass via vacuum ultraviolet/ozone (VUV/O3) activation and a multistep, low-temperature annealing process. A strong bonding strength and a bonding interface without any microcracks were obtained after annealing at 200 °C. The surfaces and bonding interface were characterized. After the organic contaminants were removed by VUV/O3, the treated surfaces were very hydrophilic. In addition, the VUV/O3-induced surface oxidation increased, resulting in oxide asperities on the substrates. These newly generated surface asperities might possess a strong deformability based on the water stress corrosion effect, leading to gap closure after low-temperature annealing. Moreover, a model for the mechanism of the VUV/O3-activated bonding was proposed.

Background Tamarix species are well known as the main host plants of Herba Cistanches, a valuable Traditional Chinese Medicine. They are also traditional medicinal plants themselves and are used to treat spleen problems, leucoderma and ocular conditions. Purpose The aim of the present study was to investigate the anti-inflammatory effect of Tamarix hohenackeri Bunge. Methods In the present study, BV-2 microglial cells were used and stimulated with lipopolysaccharide (LPS). Cell viability was tested using the MTT assay. The release of nitric oxide (NO) was determined using the Griess assay. The mRNA level of inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), interleukin (IL)-1β and IL-6 were investigated by quantitative real-time PCR (qRT–PCR). The protein levels of phosphorylated of IκBα, ERK and MEK, as well as the cytoplasmic and nuclear NF-κB p65 were tested by Western blot analysis. The translocation of the NF-κB p65 subunit from the cytosol to the nucleus was investigated by immunofluorescence staining. Results Ethyl acetate (EtOAc) extract of Tamarix hohenackeri Bunge significantly inhibited the release of NO. Phytochemical research was performed to produce 13 main constituents. Among them, compounds 6, 7, 10 and 13 were identified to be the effective components with anti-inflammatory activity. These compounds significantly inhibited the production of NO by LPS-activated BV-2 microglial cells. qRT–PCR showed that compounds 6 and 7 significantly suppressed the LPS-induced transcription of genes encoding pro-inflammatory mediators, including iNOS, TNF-α, IL-1β and IL-6. Western blot analysis showed that compound 7 inhibited the LPS-induced phosphorylation of IκBα and antagonized the LPS-induced reduction of cytoplasmic NF-κB p65 and the increase of nuclear NF-κB p65. Immunofluorescence staining showed that nuclear translocation of NF-κB p65 was suppressed by compound 7. Western blot analysis showed that compound 7 inhibited the LPS-induced phosphorylation of ERK and MEK. Conclusion The present study revealed, for the first time, the effective anti-inflammatory agents from T. Hohenackeri. Compound 7 exerted potent anti-inflammatory effects and its underlying mechanism may be associated with its capacity to inhibit NF-κB signaling pathway and the MEK/ERK activation in activated microglia. The compound may be potential candidate therapeutic agent for neurodegenerative diseases.

Direct bonding is an attractive technique for joining two mirror polished surfaces without any intermediate materials. Vacuum ultraviolet (VUV) irradiation is an effective way for cleaning surfaces as well as increasing hydrophilicity with less surface damage. However, its applications for the direct bonding of silicon and quartz glasses have seldom been explored. Therefore, in this paper, a vacuum ultraviolet/ozone (VUV/O3) activated direct bonding method for Si/Si and quartz/quartz was developed. A defect-free interface with high bonding strength was achieved after a low-temperature annealing process at 200 °C. According to water contact angle, Raman spectroscopy, atomic force microscopy, and transmission electron microscopy measurements, we demonstrated an understanding of the beneficial surface treatments from VUV irradiation. Then two models for Si/Si and quartz/quartz bonding were established separately based on low-temperature water stress corrosion. Our studies found that the increase of surface roughness with the extension of VUV irradiation time was attributed to the oxide asperities generated on the irradiated surfaces, which possessed strong deformability under the water stress corrosion effect. The excellent bonding benefits from the saturated silanol groups formed on the VUV irradiated surfaces and the positive effects of the interfacial water on the gap closure during the annealing process.

Ethnopharmacological relevance Ferula sinkiangensis K. M. Shen is a traditional Chinese medicine that has a variety of pharmacological properties relevant to neurological disorders and inflammations. Kellerin, a novel compound extracted from Ferula sinkiangensis, exerts a strong anti-neuroinflammatory effect by inhibiting microglial activation. Microglial activation plays a vital role in ischemia-induced brain injury. However, the potential therapeutic effect of kellerin on focal cerebral ischemia is still unknown. Aim of the study To explore the effect of kellerin on cerebral ischemia and clarify its possible mechanisms, we applied the middle cerebral artery occlusion (MCAO) model and the LPS-activated microglia model in our study. Materials and methods Neurological outcome was examined according to a 4-tiered grading system. Brain infarct size was measured using TTC staining. Brain edema was calculated using the wet weight minus dry weight method. Neuron damage and microglial activation were observed by immunofluorescence in MCAO model in rats. In in vitro studies, microglial activation was examined by flow cytometry and the viability of neuronal cells cultured in microglia-conditioned medium was measured using MTT assay. The levels of pro-inflammatory cytokines were measured by qRT-PCR and ELISA. The proteins involved in NF-κB signaling pathway were determined by western blot. Intracellular ROS was examined using DCFH-DA method and NADPH oxidase activity was measured using the NBT assay. Results We found that kellerin improved neurological outcome, reduced brain infarct size and decreased brain edema in MCAO model in rats. Under the pathologic conditions of focal cerebral ischemia, kellerin alleviated neuron damage and inhibited microglial activation. Moreover, in in vitro studies of LPS-stimulated BV2 cells kellerin protected neuronal cells from being damaged by inhibiting microglial activation. Kellerin also reduced the levels of pro-inflammatory cytokines, suppressed the NF-κB signaling pathway, and decreased ROS generation and NADPH oxidase activity. Conclusions Our discoveries reveal that the neuroprotective effects of kellerin may largely depend on its inhibitory effect on microglial activation. This suggests that kellerin could serve as a novel anti-inflammatory agent which may have therapeutic effects in ischemic stroke.

Silicon carbide is well known as a compelling third-generation semiconductor material. SiC-on-insulator substrate performs superior electronic isolation and operates as a high-speed and high-power platform. In contrast to existing manufacturing methods, there is an urgent need for a low temperature process with lower interfacial stress and high quality. Wafer direct bonding has been developed for many years because this technology enables composite structures regardless of material. However, the bonded sample should anneal to further improve the strength. The interfacial stress caused by high temperature is still unsolved. Plasma activated bonding is known as a method that requires a lower annealing process. Here, we adopt O 2 plasma activation as a pre-treatment and bond hydrophilic surfaces at room temperature. Furthermore, we designed a step annealing curve to reduce the maximum temperature to 200 °C while ensuring bonding strength. A uniform and defect-free bonding interface can be observed by transmission electron microscopy. This technique is suitable for fabricating high quality SiC-on-insulator platforms for optoelectronic devices.

Ischemic stroke is a global disease with high disability and mortality rates. Cognitive impairment is one of the major clinical features of ischemic stroke, and microglia-mediated inflammation has been shown to be an important contributor to the pathogenesis of ischemic stroke. Kellerin, extracted from Ferula sinkiangensis, was previously shown to inhibit microglial activation and exert a strong anti-neuroinflammatory effect. However, there is no report of the potential therapeutic effect of kellerin on ischemic stroke by targeting microglial cells. In this study, we wanted to examine the effects of kellerin on ischemic stroke in the bilateral common carotid artery occlusion (BCCAO) model and the lipopolysaccharide (LPS)-activated microglia model. We found that kellerin alleviated cognitive impairment, decreased neuronal loss, suppressed microglial activation, and transformed microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype in BCCAO mice. Moreover, in in vitro studies, we found that kellerin regulated microglial polarization and inhibited the NLRP3 and MAPK signaling pathways after LPS treatment. These findings provide a new understanding of the function of kellerin in ischemic stroke, and suggest that kellerin could be a potential therapeutic agent for the treatment of ischemic stroke.

Modulating inflammatory responses after stroke can prevent brain injury and, therefore, improve neurological outcome. Stephania japonica (Thunb.) Miers is a Chinese folk medicine with the function of dispelling the "wind and blockage" in the human body according to the Chinese medicine theory, in which the symptoms of stroke are caused by the "wind and blockage" in the body. In this paper, we for the first time linked S. japonica to stroke by clarifying fifteen alkaloidal constituents including five undescribed (1-5) ones and screening out six hasubanan type alkaloids (1-4, 7, 15) that elicited stronger anti-neuroinflammatory activities than the positive drug. Moreover, the total alkaloid fraction (ASJ) with previously undescribed 3 as the main component was subject to the in vivo evaluation of the protective effect in the MCAO-induced brain injury. The results showed that ASJ exhibited potent protective effect against brain injury in the MCAO rat model. The results reported in this paper suggested that the hasubanan alkaloids from S. japonica would be an important molecular source for discovering novel therapeutic agents for neuroinflammation-related diseases, such as stroke diseases.

X. sorbifolia is a widely cultivated ecologicalcrop in the north of China which is used to produce biodiesel fuel. It also possesses special medicinal value and has attracted keen interests of researchers to explore its bioactivity.To extract the total triterpenoid saponins from the husk of X. sorbifolia (TSX) and investigate its effects on Alzheimer's disease (AD).TSX was prepared via modern extraction techniques. Its effects on two AD animal models, as well as the preliminary mechanism were investigated comprehensively.The behavioral experiments including Y maze test, Morris water maze test and passive avoidance test were performed to observe the learning and memory abilities of the animals. ELISA assays, transmission electron microscope observation and Western blotting were employed in mechanism study.TSX, the main composition of X. sorbifolia, accounted for 88.77% in the plant material. It could significantly increase the spontaneous alternation in Y maze test (F (6, 65)=3.209, P0.01), prolong the swimming time in the fourth quadrant in probe test of Morris water maze test (F (6, 71)=4.019, P0.01), and increase the escape latency in passive avoidance test (F (6, 65)=3.684, P0.01) in AD model animals. The preliminary mechanism research revealed that TSX could significantly increase the contents of hippocampal Ach and ChAT, and enhance activity of ChAT in hippocampus of quinolinic acid injected rats (F (5, 61)=3.915, P 0.01; F (5, 61)=3.623, P0.01, F (5, 61)=4.344, P0.01, respectively). It could also increase the activities of T-AOC and T-SOD, and decrease the content of MDA in hippocampus of Aβ1-42 injected mice (F (5, 30)=5.193, P0.01, F (5, 30)=2.865, P0.05, F (5, 30)=4.735, P0.01, respectively). Moreover, it significantly increased the expressions of SYP, PSD-95 and GAP-43 in hippocampus (F (4, 27)=3.495, P0.05; F (4, 27)=2.965, P0.05; F (4, 27)=4.365, P0.01, respectively), and improved the synaptic ultra-structure damage in model rats.TSX could significantly improve the impairments of learning and memory. The preliminary mechanism might associate with its protection effects against oxidative stress damage, cholinergic system deficiency and synaptic damage. TSX are perfectly suitable for AD patients as medicine or functional food, which would be a new candidate to treat AD.

SCOPE In the present study, effect of pterostilbene on β-amyloid 1-42 (Aβ1-42 ) induced cognitive impairment in mice is investigated and explored its possible mechanism of action. METHODS AND RESULTS The behavior results show that pterostilbene alleviated Aβ1-42 -induces cognitive dysfunction assessed using the Y-maze test, novel object recognition task, Morris water maze test, and passive avoidance test. Pterostilbene alleviates neuron loss and accumulation of reactive oxygen species in Aβ1-42 treated mouse brain. Additionally, pterostilbene promotes nuclear factor-E2 p45-related factor 2 (Nrf2) nuclear translocation and enhance the transcription and expression of antioxidant genes such as heme oxygenase-1 and superoxide dismutase both in vivo and in vitro. Nrf2 inhibitor ML385 reverses the antioxidant function of pterostilbene in SH-SY5Y cells. Nrf2 is the master regulator of oxidative homeostasis and can be activated by substrate adaptor sequestosome-1 (also named p62). Pterostilbene promotes the binding of Kelch-like ECH-associated protein 1 and p62, which enhanced activation of Nrf2. CONCLUSION The present study reports that pterostilbene alleviated Aβ1-42 -induces cognitive dysfunction in mice. The mechanism of pterostilbene can be associated to the inhibition of oxidative stress through the Nrf2 signaling pathway.

The new type of artificial electromagnetic two-dimensional surface consists of an array of subwavelength unit structures arranged according to the periodicity of the dispersion curve. It has a significant role in regulating electromagnetic waves, and it has become one of the hot topics in the field of information. In this paper, the Spoof Surface Plasmon Polaritons (SSPPs) are regulated and applied to the wireless millimeter-wave base station communication. It has the characteristics of low profile, low cost, high isolation, broadband, and high gain. As a proof of concept, the antenna array is designed, simulated, processed and measured. The dual-beam adaptive antenna based on SSPPs at 10 GHz. The experimental results are in good agreement with numerical simulations. The proposed antenna has promising applications on planar wireless communication devices, such as multi-beam antennas, beam-scanning antennas, and wave controllers.

Scope The anti-neuroinflammatory effect of a novel quinolyl-substituted analogue of resveratrol (RV01) on lipopolysaccharide (LPS)-induced microglial activation is investigated, as well as the possible underlying mechanisms. Methods and results Cell viability is measured using an MTT assay. Nitric oxide (NO) release is determined by nitrite assay. The interaction between RV01 and inducible nitric oxide synthase (iNOS) is studied using molecular docking. Free radical scavenging activity and reactive oxygen species (ROS) production are determined by DPPH reduction assay and DCFH-DA assay. Pretreatment with RV01 (1-30 µm) prior to LPS (1 µg mL-1 ) stimulation decreased NO release and iNOS expression without observable cytotoxicity. RV01 reduced the mRNA levels and secretion of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). RV01 also inhibited LPS-induced ROS production and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation. Furthermore, RV01 decreases the protein expression of toll-like receptor 4 (TLR4) and inhibits the LPS-induced activation of the mitogen-activated protein kinase (MAPK) and nuclear transcription factor-κB (NF-κB) signaling pathways. Additionally, conditioned medium from microglia co-treated with LPS and RV01 alleviates the death of SH-SY5Y cells induced by conditioned medium from activated N9 microglial cells. Lastly, a mouse neuroinflammation model is further used to confirm the effect of RV01 in vivo. Conclusion These results show that RV01 suppresses microglia-mediated neuroinflammation and protects neurons from inflammatory damage, which indicates that RV01 has great potential as a nutritional preventive strategy for neuroinflammation-related diseases.

Xanthoceraside, a novel triterpenoid saponin, has been found to attenuate learning and memory impairments in AD animal models. However, whether xanthoceraside has a positive effect on synaptic morphology remains unclear. Herein, we evaluated the effects of xanthoceraside on learning and memory impairments and the abnormalities of synaptic structure in APP/PS1 transgenic mice. The behavioral experiments demonstrated that xanthoceraside attenuated the imaginal memory and spatial learning impairments, and improved social interaction. Transmission electron microscopy and Golgi staining showed that xanthoceraside ameliorated synapse morphology abnormalities and dendritic spine density deficits, respectively. Western-blot analysis identified that xanthoceraside increased the expression of SYP and PSD95, activated BDNF/TrkB/MAPK/ERK and PI3K/Akt signaling pathways, meanwhile decreased the expression of RhoA, ROCK and Snk, increased the levels of SPAR, and activated the BDNF/TrkB/cofilin signaling pathway. Taken together, our study indicated that xanthoceraside improved cognitive function and protected both synaptic morphology and dendritic spine in APP/PS1 transgenic mice, which might be related in part to its activation in the BDNF/TrkB pathway.

Direct bonding at low temperature is an attractive technology for joining dissimilar materials without large thermal stress. Vacuum ultraviolet (VUV) activation is an effective way for surface cleaning with less damage. Meanwhile, the obtained hydrophilic surfaces are also beneficial for the direct bonding. In this paper, we developed a VUV/O3 activated bonder for the direct bonding of Si-based materials at low temperature. High bonding strength for Si/glass and glass/glass bonded pairs was achieved after annealing at 200 oC. Atomic force microscopy (AFM) and water contact angle tester were conducted to analyze effects of VUV on surface roughness and wettability. Si-Si, Si-glass and glass-glass bonding interfaces were also observed by transmission electron microscopy (TEM). Defect-free and tight interfaces of Si/Si and Si/glass were obtained. However, the glass/glass bonding interface was full of microvoids which can be attributed to the less deformation of subsurfaces during the annealing process. Moreover, based on the surface and interface studies, bonding mechanisms for Si-based materials direct bonding via VUV activation was discussed.

Direct bonding is an attractive technique for joining two mirror polished surfaces without any intermediate materials. Vacuum ultraviolet (VUV) irradiation is an effective way for cleaning surfaces as well as increasing hydrophilicity with less surface damage. However, its applications for the direct bonding of silicon and quartz glasses have seldom been explored. Therefore, in this paper, a vacuum ultraviolet/ozone (VUV/O

Pull tensile test is commonly used to evaluate the bonding strength. But it is time-consuming using glue to attach the fixtures (jigs). In this paper, a novel method for bonding strength evaluation without using glue is developed based on the principles of the material mechanics and fracture mechanics. After two specimen are bonded by a cross structure, the pulling forces are applied at the relevant positions based on different bonding materials. Then we can obtain the bonding strength according to the accurate fracture position and the pulling force value. In addition, we established a finite element model to verify the evaluation results for the silicon/silicon direct bonding strength. The simulation results of the tensile strength are greatly consistent with our theoretical method.

The combination of lithium niobate (LiNbO3) and glass without an intermediate layer is an essential component of micro/nanofluidics and optical waveguides. Direct bonding is a popular method for joining homo/heterogeneous materials into a single composite. However, direct bonding of LiNbO3 and glass is extremely difficult due to the chemical inertness of LiNbO3 and the large mismatch of the coefficients of thermal expansion of these materials. In this work, we realized direct bonding of LiNbO3 and glass via VUV/O3 activation at 150 °C. Focused ion beam microfabrication tests and observation by scanning electron microscopy and transmission electron microscopy confirmed the strong LiNbO3/glass bonding interfaces. The excellent transmittance and piezoelectric properties of the direct bonded pairs and the single-crystal orientation of the LiNbO3 close to the glass demonstrated that the VUV/O3 activated direct bonding method was suitable for the fabrication of high-performance surface acoustic wave (SAW)-actuated LiNbO3-based devices. Additionally, we investigated the bonding mechanism through water contact angles, atomic force microscopy, Raman spectroscopy, FTIR spectroscopy, and adhesion measurements.

Hydrophilic bonding is commonly used in the wafer bonding field. Water management is of great importance to obtain good bonding quality over the entire bonded pairs. However, current wafer bonding equipments do not have the function of regulating the surface humidity prior to bonding. It is difficult to make a quantitative study on the role of moistures in the bonding process. In this paper, a novel surface humidity controlled bonder is developed to optimize the water adsorption on the wafer surface prior to bonding and improve the bonding quality using cooling as well as heating functions. For the sufficient surface humidity, the water molecules may bond together via Si-OH groups on the silica surfaces, and then they can compensate the gap between the bonded wafers resulting a weak hydrogen-bonding connected Si-OH···(H 2 O) x ···HO-Si interface structure forming a good prebonding interface.

Xanthoceras sorbifolia, a traditional Chinese folk medicine with anti-inflammatory effects, has been used for a long time in China, especially in the Inner Mongolian area for the treatment of rheumatism. Inflammation is one of the main causes of Alzheimer's disease (AD). AD is characterized by aggregation of amyloid β-peptide (Aβ) plaques, neurofibrillary tangle formation, synaptic dysfunction and neuronal loss. To investigate whether Xanthoceras sorbifolia extracts (XSE) improve cognition and protect dendritic spines, we performed behavioral tests to investigate learning and memory in an Aβ25-35-induced dementia animal model of AD as well as Golgi staining to observe dendritic spine formation in CA1 pyramidal neurons and western blots to test the expression levels of PSD95, BDNF and downstream signaling pathways. Our results indicated that oral treatment with XSE significantly reduced cognitive impairments in behavioral tests (passive avoidance test, novel object recognition test, Y-maze test and Morris water maze test). Golgi staining results revealed that XSE ameliorated dendritic spine density deficits in CA1 pyramidal neurons in the hippocampus. Western blot analysis suggested that XSE upregulated PSD95, which is the major scaffolding protein in synapses. BDNF levels and the ratio of p-TrkB/TrkB increased, and the expression of the RhoA, a member of the Rho-GTPase family, and its downstream target protein ROCK2 decreased in the dementia animal model following treatment with XSE. Therefore, the cognition-improving effects of XSE probably resulted from dendritic spine protection effects through regulation of BDNF signaling pathways.

We demonstrate a facile bonding process for combining silicon and quartz glass wafers by a two-step wet chemical surface cleaning. After a post-annealing at 200 °C, strong bonding interfaces with no defects or microcracks were obtained. On the basis of the detailed surface and bonding interface characterizations, the bonding mechanism was explored and discussed. The amino groups terminated on the cleaned surfaces might contribute to the bonding strength enhancement during the annealing. This cost-effective bonding process has great potentials for silicon- and glass-based heterogeneous integrations without requiring a vacuum system.

Because of the complicated configuration in MEMS devices, significant technical challenges are presented for the interconnection of dissimilar materials. Since tin soldering is an effective method for joining dissimilar materials, there are still some reliability problems in later service process, such as remelting of Sn solder, excessive microstructure evolution. In the present work, a parallel gap resistance microwelding method was developed for forming reliable Cu wire/Au plating interconnection. In an attempt to avoid fragile electronic components, an ohmic contact tip onto the electrodes was utilized. Experimental results revealed that solid state welding was obtained with a relatively electric current intensity within 20 ms. No weld nugget was generated at the Cu/Au interface. The joule heat-induced temperature affected microstructures as well as mechanical properties of the joints, mainly depending on three parameters (welding voltage, welding time and electrode force). The maximum joint breaking force was 24 g with the welding voltage of 0.5 V for 16 ms and under the pressure of 0.56 N. The ANSYS simulation results indicated that the weld geometry changed with welding time.