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A high concentration of blood ammonia can lead to failure of early embryo implantation in dairy cows. Progesterone (P4) is an important hormone that regulates the changes of uterine receptivity and participates in pregnancy during early implantation. However, whether P4 alleviates the harmful effects of blood ammonia is unknown. Therefore, this experiment treated bovine endometrial epithelial cells (BEEC) with ammonia chloride and P4. The results showed that ammonia decreased the viability of BEEC, upregulated the ROS level and apoptosis rate, and upregulated the expressions of Bax, Bcl-2, P53, Cyt-c, caspase-3, caspase-8 and caspase-9. It also upregulated the expressions of TLR4, NF-κB, and in turn, produced a large amount of IL-6 and downregulated the expressions of EGF and VEGF. After co-treating BEEC with ammonia and P4, P4 had no alleviating effect on cell viability, ROS and apoptosis, but downregulated the expressions of TLR4, NF-κB, IL-6, and upregulated the expressions of LIF, EGF and VEGF. Inhibition of STAT3 signaling pathway, LIF expression was not affected, and VEGF expression was down-regulated. Using LIF treated BEEC, VEGF expression was upregulated, but after the addition of inhibitors, the expression of VEGF was not upregulated by LIF. Therefore, progesterone could not alleviate the oxidative stress and apoptosis induced by ammonia in BEEC. However, progesterone ameliorated the inflammation and receptivity genes of BEEC induced by ammonia via the NF-κB and LIF/STAT3 signaling pathways.

Background NMDAR hypofunction has been implicated in several psychiatric disorders with an impairment of cognitive flexibility. However, the molecular mechanism of how NMDAR hypofunction with decreased NMDAR tone causes the impairment of cognitive flexibility has been minimally understood. Furthermore, it has been unclear whether hippocampal astrocytes regulate NMDAR tone and cognitive flexibility. Methods We employed cell-type specific genetic manipulations, ex vivo electrophysiological recordings, sniffer patch recordings, cutting-edge biosensor for norepinephrine, and behavioral assays to investigate whether astrocytes can regulate NMDAR tone by releasing D-serine and glutamate. Subsequently, we further investigated the role of NMDAR tone in the heterosynaptic long-term depression, metaplasticity and cognitive flexibility. Results We found that hippocampal astrocytes regulate NMDAR tone via Best1-mediated co-release of D-serine and glutamate. Best1 knockout mice (Best1 KO) exhibited reduced NMDAR tone and impairments of homosynaptic and α1-adrenergic receptor-dependent heterosynaptic long-term depression, which leads to the defects in metaplasticity and cognitive flexibility. These impairments in Best1 KO can be rescued by hippocampal astrocyte-specific Best1 expression or enhanced NMDAR tone through D-serine supplement. Importantly, D-serine injection in Best1 KO during initial learning rescues subsequent reversal learning. Conclusions These findings indicate that NMDAR tone during initial learning is important for subsequent learning, and hippocampal NMDAR tone regulated by astrocytic Best1 is critical for heterosynaptic long-term depression, metaplasticity and cognitive flexibility.

Graphene-based nanomaterials encapsulated with corrosion inhibitors are promising materials for achieving smart coatings with healable properties. However, the low loading contents of inhibitors (10%–20%) and the cumbersome synthesis processes remain as urgent problems for practical applications. Here, we propose a novel strategy for preparing healable coatings with the enhanced loading of inhibitors enabled by ultra-highly exfoliated graphene and mussel-inspired chemistry. Ultra-highly exfoliated graphene (1355 m2/g) was achieved via a unique one-pot method of H2O2/KOH catalytic exfoliation and etching with residual KOH. Polydopamine (PDA), as a green corrosion inhibitor, effectively promoted the adsorption of benzotriazole (BTA) on graphene via facile co-adsorption. The corrosion perception of this smart coating with the dual healable effect of BTA/PDA was triggered by PDA decomposition from corrosion-induced pH variations. Thus, the coating exhibited an increased impedance modulus (3.31 × 1010 Ω cm2) even after 30 days of immersion (three orders of magnitude higher than that of an epoxy coating), owing to the outstanding barrier effect of the ultra-highly exfoliated graphene and high loading content of inhibitors (30%). This study has a great significance for the design of high-loading smart nanomaterials for sustainable smart systems.

The blood-testicular barrier (BTB) is involved in spermatogenesis, protects sperm development, and plays a crucial role in the reproductive process. Tight junctions (TJs) between Sertoli cells (SCs) are the key structure of (BTB), and if its structure is damaged, BTB function is affected. The cellular inflammation caused by Gram-negative bacteria affects the structural integrity of TJs. Melatonin (MT) has anti-inflammatory effects; however, the effect of MT in newborn calf SCs is unknown. Therefore, this experiment studied the protective effect of MT. The results showed that LPS upregulated TLR4, MyD88, and NF-κB expressions, in turn, activated the TLR4/MyD88/NF-κB signaling pathway, produced a large amount of IL-6 and IL-1β, downregulated the expression of ZO-1 and Occludin, and reduced the viability of SCs, which resulted in the inflammatory response of SCs and damage of TJs. The addition of MT decreased TLR4, MyD88, and NF-κB expressions, it then inhibited the activation of TLR4/MyD88/NF-κB signaling pathway, downregulated the expression of IL-6 and IL-1β, upregulated the expression of ZO-1 and Occludin, and increased the cell viability, thereby alleviating the inflammatory response of SCs, and restored the TJs structure. Overall, our results reveal that MT can alleviate LPS-induced in newborn calf SCs Inflammation and TJs injury through TLR4/MyD88/NF-κB signaling pathway.

Microwave absorption materials (MAMs), which can simultaneously show high reflection loss (RL) and broad effective absorbance band (EAB) at a thinner matching thickness, were meaningful to the settlement of current electromagnetic wave pollution. Herein, all-polymer derived carbon foam with unique molecular-level interpenetrating carbon network (ICN) heterojunction interface was constructed. The heterostructure was fabricated through carbonizing the molecular-level miscible interpenetrating polymer networks (IPN) of polyimide foam (PIF) and bismaleimide (BMI), while target heterojunction was proved through several characterizations. Benefitting from stronger polarization loss gene derived from countlessly molecular-level heterojunction interface of ICN, higher RL value could be realized at a thinner matching thickness. As a result, when only orthogonal polymerizing 5 wt% BMI with PIF, maximum RL value of corresponding carbon foam (CPIF-CBMI-5%) could achieve −72.8dB at the matching thickness of only 2.05 mm. In addition, the matching thicknesses of CPIF-CBMI-5% that covered the whole X band and Ku band were significantly decreased by 25% (3.75 mm to 2.8 mm) and 21% (2.6 mm to 2.05 mm) respectively, which was also superior to most foam materials that decorated by traditional loading or doping. Moreover, maximum EAB of CPIF-CBMI-5% could also achieved 6.2 GHz at 2.05 mm and its density was as low as 0.026 g/cm3.

In this paper, a micromechanics-based constitutive model is proposed for linear viscoelastic particle-reinforced composites with interphase based on the theoretical homogenization framework in the time domain that we recently proposed for viscoelastic composites. All the composite's phases (i.e., the matrix, particle and interphase) are considered as linear viscoelastic materials, whose constitutive responses are governed by the general Maxwell model. The interphase with varying viscoelastic property is approximated by the multiple homogenized layers. The constitutive model of the composites is multiplicatively decomposed as two parts: (1) the effective relaxation function characterizes the time-dependent behaviors, and (2) the referred elastic part refers to the long-term responses. The classical composite-sphere model and three-phase model are extended to derive the variables involved in the constitutive model for the bulk and shear behaviors, respectively. The comprehensive numerical simulations, including the effects of the number of interphase layer, interphase thickness, particle content and loading condition, are carried out to validate the proposed constitutive model. The results reveal that the constitutive model can predict well the viscoelastic behaviors of the particle-reinforced composites with interphase. The validated constitutive model is then applied to identify the viscoelastic properties of the interphase by fitting the predictive results and the experimental data of the “overall” composites. The results show the good consistency for the interphase properties between the theoretical identification and the experimental observation. The discussion of the interphase percolation is then carried out, and the findings demonstrate again that the constitutive model can also give good predictions under the percolation situation.

Drug addiction is characterized by a sustained vulnerability to relapse even after long periods of abstinence. A deeper understanding of the brain systems underlying this state could inform therapeutic strategies with novel prognostic biomarkers aimed at preventing renewed drug seeking. Most drugs of abuse, in particular psychostimulants such as cocaine, lead to long-lasting mesolimbic dopamine system adaptations, that ultimately facilitate drug seeking following exposure to drug-paired cues. This “dopaminergic hypothesis” of relapse has been previously addressed, but technical limitations in measuringin vivodopamine release have precluded the assessment of its sufficiency without introducing pharmacological, electrical, or optogenetic confounds. Using a dopamine receptor-based fluorescent sensor in freely moving mice, we show that long-lasting dopamine recordings in the nucleus accumbens (NAc), throughout the animal’s entire history of cocaine self-administration, are strong predictors of relapse as well as the time it takes an animal to extinguish its drug seeking behavior. Moreover, we reveal previously unseen sex-specific trajectories of cocaine-related phasic dopamine responses from acquisition to relapse. We show that males exhibit higher-amplitude phasic dopamine responses, a trait accompanied by a greater resistance to extinguish their cocaine seeking, compared to females. Furthermore, we show that a semi-parametric model of the transition to extinction – using only multivariate patterns of dopamine release and sex as covariates – faithfully recapitulates male-specific vulnerability to persistent cocaine seeking. In conclusion, we present a predictive model of reinstatement behavior that uses information exclusively conveyed by NAc phasic dopamine responses, thus confirming, and actuating the sufficiency of the dopaminergic hypothesis of relapse.

Histamine (HA) is a key biogenic monoamine involved in a wide range of physiological and pathological processes in both the central and peripheral nervous systems. Because the ability to directly measure extracellular HA in real time will provide important insights into the functional role of HA in complex circuits under a variety of conditions, we developed a series of genetically encoded G-protein-coupled receptor-activation-based (GRAB) HA (GRABHA) sensors with good photostability, sub-second kinetics, nanomolar affinity, and high specificity. Using these GRABHA sensors, we measured electrical-stimulation-evoked HA release in acute brain slices with high spatiotemporal resolution. Moreover, we recorded HA release in the preoptic area of the hypothalamus and prefrontal cortex during the sleep-wake cycle in freely moving mice, finding distinct patterns of HA dynamics between these specific brain regions. Thus, GRABHA sensors are robust tools for measuring extracellular HA transmission in both physiological and pathological processes.

Cu modified carbon nanotubes (Cu-CNTs) doped flux were prepared in this paper, the influence of the composite flux on the evolution of microstructure and shear strength of Sn-3.0Ag-0.5Cu (SAC305) solder joints were investigated, the ultrasonic vibration (USV) was applied for the solder joint during reflowing. Experiments were designed to modify the CNTs with Cu nanoparticles through electroless modification process. Transmission electron microscopy (TEM) was utilized to obtain the graph of modified CNTs. Using X-ray photoelectron spectroscopy (XPS) spectra to prove that the CNTs were successfully modified with Cu nanoparticles. Compared with the solder joint without USV, the application of USV on the solder joint would alter the morphologies of interfacial IMC layer and grains, reduce the IMC thickness and grain size by 16.6 % and 65.6 %, respectively. Reflow process was implemented to evaluate the microstructure evolution and interfacial reaction of SAC305 solder joint with different content of Cu-CNTs doped flux with USV. It was found that the presence of Cu-CNTs could reduce the thickness and grain size of interfacial intermetallic compound (IMC) within solder joint by 3.1 % and 5.25 %, respectively. After addition of the Cu-CNTs in the flux, the thickening of IMC layer and the coarsen of interfacial IMC grain were suppressed, the optimal inhibition effect was gained when the content of Cu-CNTs was 0.1 wt.%. The shear test was conducted for the Cu/SAC305/Cu solder joint with flux containing Cu-CNTs under different soldering condition, the results indicated that as the content of the Cu-CNTs in the flux increased, the shear strength was significantly enhanced by up to 16.8 %. Furthermore, the application of USV could enhance the shear strength by up to 14.2 % as well, The fracture type of solder joints without USV treatment also changed from ductile-brittle mixed type to ductile type as the content of Cu-CNTs in the flux increased. While, the fracture type of all the solder joints with USV treatment was ductile type.