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Background: The neuropeptide orexin promotes arousal from general anaesthesia, however the neuronal circuits that mediate this effect have not been defined. We investigated whether orexinergic neurones modulate the basal forebrain (BF) and locus coeruleus (LC) in emergence from anaesthesia.Methods: Hcrtcre rats were generated using a CRISPR/Cas9-based approach. Viruses encoding optogenetic probes were injected into the perifornical lateral hypothalamic (PeFLH) area, optogenetic fibres were embedded in the PeFLH, BF, or LC, and changes in anaesthesia state under 1.4 vol% or 0.8 vol% isoflurane were determined.Results: In the PeFLH, 98.8% (0.4%) of orexin-A-positive cells expressed tdTomato, and 91.9% (2.2%) of tdTomato cells were orexin-A-positive. Under 1.4 vol% isoflurane anaesthesia, compared with control groups, burst suppression ratio was less, and emergence time was shorter in groups with optogenetic activation of orexinergic cell bodies in the PeFLH (923 [162] vs 493 [68] s, P=0.0003) or orexinergic terminals in the BF (937 (122) vs 674 (108) s, P=0.0049) or LC (913 [128] vs 742 [76] s, P=0.022). Optical stimulation of orexinergic terminals in the BF and LC also improved the movement scores of rats under 0.8 vol% isoflurane anaesthesia.Conclusions: Activation of orexinergic terminals in the FB or LC mediates facilitation of emergence from anaesthesia by orexinergic neurones during isoflurane anaesthesia. [ABSTRACT FROM AUTHOR]

In recent years, transition-metal silicon-based high temperature materials have attracted more and more attention due to their excellent physical and chemical properties. In this paper, we explored the phase stability, mechanical, anisotropy and thermodynamic properties of TM 5 Si 4 (TM = Sc, Y, Ti, Zr and Hf) compounds by first-principles calculations. The results indicate that TM 5 Si 4 compounds exhibit the thermodynamical and dynamical stability. And Hf 5 Si 4 exhibits the best phase stability among five compounds. The orthorhombic Sc 5 Si 4 and Y 5 Si 4 are ductile, but the tetragonal Ti 5 Si 4 , Zr 5 Si 4 and Hf 5 Si 4 are brittle. The elastic anisotropies of TM 5 Si 4 were demonstrated by the 3D contours and 2D projections of elastic modulus. The results confirm that the order of anisotropy is as follows: Zr 5 Si 4 < Hf 5 Si 4 < Ti 5 Si 4 < Sc 5 Si 4 < Y 5 Si 4. TM-Si bonds can be formed in TM 5 Si 4 silicides for the strong localized hybridization between TM-d and Si-3p states. Moreover, the thermal parameters confirm that five TM 5 Si 4 silicides display the better thermal stability at elevated temperature. • The mechanical, and thermodynamic properties of TM 5 Si 4 compounds were explored. • The results showed that the TM 5 Si 4 compounds exhibit the phase stability. • The orthorhombic Sc 5 Si 4 and Y 5 Si 4 s exhibit ductile behavior. • The elastic anisotropies of TM 5 Si 4 were intuitively demonstrated. [ABSTRACT FROM AUTHOR]

In present work, the effects of vacancy defects on the mechanical and thermodynamic properties of Cr 5 Si 3 have been investigated using the first-principles. The occupation mechanism of oxygen atoms in Cr 5 Si 3 is also carefully analyzed and discussed. The vacancy formation, lattice vibrations, electronic structure, elasticity and thermodynamic parameters of Cr 5 Si 3 were calculated separately. The results show that Cr 5 Si 3 is stable and irrespective of the presence of vacancies or oxygen atoms occupation in it. In addition, the Si vacancies cause Cr 5 Si 3 to undergo a brittle to ductile transition, which originates the weak hybridization between Cr and Si atoms. Importantly, when the Si -Va2 vacancy is occupied by oxygen atom, Cr 5 Si 3 undergoes a brittle to ductile transition despite its poor hardness and resistance to deformation, which is attributed to the formation of weak Cr–O bonds. Furthermore, both the presence of vacancy defects and the introduction of oxygen atoms result in Cr 5 Si 3 exhibiting the greater phase stability and better thermal properties. • The influence of vacancies defects and oxygen atoms occupation on physical properties of Cr 5 Si 3 is studied. • These models are stable in Cr 5 Si 3. • The vacancies defects and oxygen atoms occupation induced brittle-to-ductile transition. [ABSTRACT FROM AUTHOR]

Sophisticated stage-discharge rating curves for radial gates are essential to modernization efforts in water conservancy and irrigation projects. However, it is a challenging hydraulic issue to accurately determine discharges through radial gates, especially when subjected to highly submerged flow conditions. According to the variation trend of jet Froude number and the mechanism of energy dissipation subjected to submerged flows, a new criterion was proposed to subdivide submerged flow into partially submerged and totally submerged flows. Thus, the three stage-discharge equations were developed for free flow, partially submerged flow and totally submerged flow, respectively. With the aid of the experimental data of single radial gate and the field data of multi-radial gates, the proposed discharge calibration method, referred to as the identification method, was tested and verified. The results indicated the discharge prediction accuracies were satisfactory, in which the mean absolute percentage errors were less than 10%. The proposed method is feasible and easily programmed. • Submerged flows through gates are classified as partially and totally submerged flow conditions. • Jet Froude numbers are important indicators to distinguish submerged flow conditions. • Variations of jet Froude number are related to both relative gate openings and submergence ratios. • Stage-discharge relationships should be calibrated for parallel radial gates in practice. [ABSTRACT FROM AUTHOR]

Depression has emerged as the predominant psychiatric affliction affecting individuals. Prior research has substantiated the antidepressant properties exhibited by numerous anesthetics. Sevoflurane, a widely utilized inhalant anesthetic in clinical practice, remains relatively uncharted in terms of its specific antidepressant effects. In this study, we used open field test, forced swimming test and novelty-suppressed feeding test to investigate the anxiety and depression-like behaviors in C57BL/6 mice following the inhalation of sevoflurane. We then used western blotting to scrutinized the expression levels of proteins associated with the brain-derived neurotrophic factor (BDNF)-tryosine receptor kinase B (TrkB) pathway in the hippocampus and prefrontal cortex. To further investigate whether sevoflurane exerts antidepressant-like effects via the BDNF-TrkB pathway, we downregulated TrkB expression by administering siRNA into the lateral ventricle. We found that the inhalation of 2.5 % sevoflurane exerted a significant antidepressant-like effect, accompanied by an elevation in p-TrkB expression levels in the hippocampus and prefrontal cortex. Intriguingly, this antidepressant-like effect was abrogated following the downregulation of TrkB expression through the microinjection of siRNA into the lateral ventricle. In conclusion, this study provides evidence supporting the notion that sevoflurane exerts its antidepressant-like effect via the BDNF-TrkB signaling pathway. [ABSTRACT FROM AUTHOR]

General anaesthetics have been widely applied to induce reversible loss and recovery of consciousness in clinical practice and have been shown to have reliably safe profiles. Since brief exposure to general anaesthetics can result in long-lasting and global changes in neuronal structures and function, these drugs also exhibit strong therapeutic potential for mood disorders. Preliminary and clinical studies have suggested that the inhalational anaesthetic drug sevoflurane might relieve symptoms of depression. However, the antidepressant effects of sevoflurane and the underlying mechanisms remain elusive. In the present study, we confirmed that the antidepressant and anxiolytic effects of inhaling 2.5% sevoflurane for 30 min were comparable to those of ketamine and could be sustained for 48 h. Activation of GABAergic (γ-aminobutyric acidergic) neurons in the nucleus accumbens core by chemogenetics was shown to mimic the antidepressant effects of inhaled sevoflurane, whereas inhibition of these neurons significantly prevented these effects. Considered together, these results suggested that sevoflurane might exert rapid and long-lasting antidepressant effects via modulation of neuronal activities in the nucleus accumbens core nucleus. [ABSTRACT FROM AUTHOR]

To improve tribological performance of chemically bonded phosphate ceramic coatings, the graphene nano-platelets (GNPs) were selected as the reinforcement. Tribological experiment and the analysis of SEM, EDS and Raman were conducted to clarify the mechanism of graphene on the improvement of tribological performance. It was found that, the worn surface of the coating with GNPs is smoother than the one without GNPs, and these GNPs were extruded out and adhered to the worn surface forming the lubricating tribofilm. Besides, the wear volume decreases with the introduction of GNPs. The reason behind this is that these GNPs can lead to the absorption of the fracture energy, which further can improve the mechanical property of the ceramic. This improvement makes the ceramic more tolerant to damage during the wear. Additionally, the decrease of the internal stress of contact surface because of the large contact surface induced by the smooth worn surface results in the lower wear. The friction coefficient shows the similar trends with the wear volume. The lubricant effect of the adhered lubricating tribofilm stemming from the weak interfacial shear strength between graphene platelets dominantly leads to the decrease in friction coefficient. Besides, the smaller internal stress induced by the smooth surface also contributes to the low friction coefficient because of the direct proportionality between the interfacial shear strength and the contact pressure. [ABSTRACT FROM AUTHOR]

• Calycosin had neuroprotection on neurons injured by oxygen-glucose deprivation reperfusion in vitro. • Calycosin exerts neuroprotective effects against ischemia–reperfusion injury in vivo. • The ERK signaling pathway participates in the neuroprotective role of calycosin. Calycosin is a natural product extracted from some plant families and exhibits various biological properties. But the effect of calycosin on cerebral ischemia–reperfusion injury has not been fully elucidated. In this study, the neuroprotective effect of calycosin treatment on the differentiated SH-SY5Y cells exposed to OGD was evaluated using MTT and flow cytometry. Rats that were pretreatment with calycosin were subjected to MCAO, neurological behavior scores and brain infarct volume were evaluated. The protein expression of pERK/ERK were assessed using Western blot. siRNA-pERK and U0126 were administered to investigate the impact of the ERK pathway on calycosin preconditioning. The results demonstrated the neuronal viability in the calycosin-treated SH-SY5Y cells increased significantly, and the rate of apoptosis decreased compared with the Oxygen-glucose deprivation only SH-SY5Y cells. Calycosin pretreatment reduced infarct volume and improved neurological outcome in rats subjected to MCAO. Administration of calycosin increased the ratio of pERK/ERK expression, which was down-regulated in ischemia–reperfusion group. Down-regulation of pERK/ERK significantly attenuated the neuroprotective effect induced by calycosin pretreatment in vitro and in vivo. We concluded calycosin treatment could induce a neuroprotective effect against ischemia, which was related to the regulation of the ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

Anesthesia inhibits neural activity in the brain, causing patients to lose consciousness and sensation during the surgery. Layers 2/3 of the cortex are important structures for the integration of information and consciousness, which are closely related to normal cognitive function. However, the dynamics of the large-scale population of neurons across multiple regions in layer 2/3 during anesthesia and recovery processes remains unclear. We conducted simultaneous observations and analysis of large-scale calcium signaling dynamics across multiple cortical regions within cortical layer 2/3 during isoflurane anesthesia and recovery in vivo by high-resolution wide-field microscopy. Under isoflurane-induced anesthesia, there is an overall decrease in neuronal activity across multiple regions in the cortical layer 2/3. Notably, some neurons display a paradoxical increase in activity during anesthesia. Additionally, the activity among multiple cortical regions under anesthesia was homogeneous. It is only during the recovery phase that variability emerges in the extent of increased neural activity across different cortical regions. Within the same duration of anesthesia, neural activity did not return to preanesthetic levels. To sum up, anesthesia as a dynamic alteration of brain functional networks, encompassing shifts in patterns of neural activity, homogeneousness among cortical neurons and regions, and changes in functional connectivity. Recovery from anesthesia does not entail a reversal of these effects within the same timeframe. [Display omitted] • Innovative simultaneous observation of cortical neuron ensemble dynamics across brain regions in vivo. • Cortical layer 2/3 neuron ensembles exhibit different classification features across states of consciousness. • Homogeneous activity among cortical regions under anesthesia contrasts with increased variability during recovery. • Large-scale neural activity shows that cortical connectivity changes dynamically during anesthesia and recovery. [ABSTRACT FROM AUTHOR]

The potential of oleosins to act as carriers for recombinant foreign proteins in plant cells has been established. Using the oleosin fusion technology, the protein can be targeted to oil bodies in oilseeds by fusing it to the N- or C-terminus of oleosin. In this study, aFGF was expressed in Arabidopsis thaliana seeds via oleosin fusion technology. A plant-preferred aFGF gene was synthesized by optimizing codon usage and was fused to the C-terminus of the A. thaliana 18.5 kDa oleosin gene. The fusion gene was driven by the phaseolin promoter to confer seed-specific expression of the human acidic fibroblast growth factor in A. thaliana . The T-DNA region of the recombinant plasmid pKO-aFGF was introduced into the genome of Arabidopsis thaliana by the floral dip method. The aFGF protein expression was confirmed by SDS-PAGE and western blotting. The biological activity showed that oil bodies fused to aFGF stimulated NIH/3T3 cell proliferation activity. [ABSTRACT FROM AUTHOR]

Background: As a crucial node of the corticolimbic model, the striatum has been demonstrated in modulating emotional cues in pediatric bipolar disorders (PBD), the striatal distinction in structure and function between PBD-I and PBD-II remains unclear.Methods: MRI data of 36 patients in PBD-I, 22 patients in PBD-II and 19 age-gender matched healthy controls (HCs) were processed. Here, we investigated structural and functional alterations of 8 subregions of striatum (bilateral nucleus accumbens, caudate, putamen and globus pallidus) by analyzing MRI data.Results: We found volume reduction of the right pallidum, the significant positive correlation between the number of episodes and the functional connectivity between left pallidum and right caudate in PBD-I patients, abrupted prefrontal-striatal-thalamic functional connectivity in PBD-I group and decreased functional connectivity in PBD-II relative to HCs and PBD-I.Limitations: Future studies should enroll more subjects and adopt a longitudinal perspective, which could help to discover striatum structural or functional alterations during subject-specific clinical progress in different states.Conclusions: Results of the present study confirmed that structural and functional abnormality of striatum may be helpful in identifying PBD clinical types as distinctive biomarkers. The interruptions of the prefrontal-striatal-thalamic circuits may provide advantageous evidence for expounding the role of striatum in bipolar disorders etiology. Thus, potential mechanisms of dysfunction striatum need to be formulated and reconceptualized with multimodal neuroimaging studies in future. [ABSTRACT FROM AUTHOR]

Alterations of brain signal complexity may reflect brain functional abnormalities. In adolescent bipolar disorder (ABD) distribution of brain regions showing abnormal complexity in different mood states remains unclear. We aimed to analyze brain entropy (BEN) alteration of functional magnetic resonance imaging (fMRI) signal to observe spatial distribution of complexity in ABD patients, as well as the relationship between this variation and clinical variables. Resting-state fMRI data were acquired from adolescents with bipolar disorder (BD) who were in manic (n = 19) and euthymic (n = 20) states, and from healthy controls (HCs, n = 17). The differences in BEN among the three groups, and their associations with clinical variables, were examined. Compared to HCs, manic and euthymic ABD patients showed increased BEN in right parahippocampal gyrus (PHG) and left dorsolateral prefrontal cortex (DLPFC). There was no significant difference of BEN between the manic and the euthymic ABD groups. In manic ABD patients, right PHG BEN exhibited significantly positive relationship with episode times. Increased BEN in right PHG and left DLPFC in ABD patients may cause dysfunction of corticolimbic circuitry which is important to emotional processing and cognitive control. The positive correlation between PHG BEN and episode times of manic ABD patients further expressed a close association between brain complexity and clinical symptoms. From the perspective of brain temporal dynamics, the present study complements previous findings that have reported corticolimbic dysfunction as an important contributor to the pathophysiology of BD. BEN may provide valuable evidences for understanding the underlying mechanism of ABD. • Adolescent bipolar disorder(ABD) showed increased brain entropy(BEN) in parahippocampal gyrus/dorsolateral prefrontal cortex. • There is a close association between brain complexity(BEN) and clinical symptom(episode times) in manic ABD. • Altered brain temporal dynamics of the present study provided further proof of vital role of corticolimbic dysfunction in ABD. • BEN alteration may be not mood state specific, and it provide valuable evidence for the underlying mechanism of ABD. [ABSTRACT FROM AUTHOR]

Basic fibroblast growth factor (bFGF) is a member of the fibroblast growth factors family. It is a highly specific mitogenic factor for many cell types, as though it be involved in wound repair, angiogenesis, nerve nutrition and embryonic development etc. Oil bodies have been applied for medicine, foodstuff and industry field. The heterogonous proteins expressed in oil bodies have distinct advantages, such as less purification steps and low costs. In this study, bFGF was expressed in A. thaliana seeds using oleosin fusion technology. The pOTB-bFGF vector contained an oleosin-bFGF fusion gene and a glufosinate resistance gene for selection. Transgenic A. thaliana lines were obtained by the floral dip method and protein expression was identified by SDS-PAGE and western blotting in transgenic A. thaliana lines. Moreover, MTT assays showed that the oil bodies expressed oleosin-bFGF fusion protein had a remarkable proliferation effect on NIH/3T3 cells and animal experiments showed that it could effectively decrease wound size and accelerate granulation tissue maturation. In conclusion, this may be a better method of producing oleosin-bFGF fusion protein to meet the increasing demand in its pharmacological application. [ABSTRACT FROM AUTHOR]

• During eight years of prototype monitoring, the variations of the dielectric constant of natural ice were found. • One hundred and fifty-eight measuring points were compared using the drill-hole and GPR methods. • Using temperature and voltage measuring rods installed in the ice, the water content in the natural ice was measured. • The effects of air bubbles, sediment, and water upon the ice's dielectric constant were discussed. • The dielectric constant of natural ice was analyzed. Ground-penetrating radar (GPR) is a non-contact measurement method widely used to determine ice thickness, which is an important hydrological parameter of rivers in winter. The accuracy of GPR measurements of ice thicknesses is highly dependent on the dielectric constant value of ice. Research on the dielectric constant of ice has mainly focused on pure ice; however, pure ice is not commonly found in natural rivers. In fact, hydrodynamic and meteorological factors, as well as boundary conditions, affect ice in natural rivers, which can be treated as a mixture of pure ice, air bubbles, sediment, and pure water. Therefore, the dielectric constant of ice in natural rivers often differs from the theoretical value of pure ice, a fact that has often been neglected in prototype measurements. During eight years of prototype monitoring in the Heilong River and Yellow River (China), it was found that variations in the dielectric constants of ice in the two rivers produced errors in the GPR ice thickness measurements. In this study, we measure the dielectric constant of ice at 158 measurement points across more than 20 river sections, and we present a recommended range of values for the dielectric constant. Regarding media, such as air bubbles, sediment, and water in natural river ice, we analyze sand (both dry and wet) in ice-bound sediment and the effects of air bubbles, sediment, and water upon the ice's dielectric constant. Using temperature and voltage measuring rods installed in the ice, we demonstrate that the water content in the ice differs significantly according to the freeze-up and breakup periods. The present study recommends guidelines including suitable timing, ice-condition, and dielectric-constant reference values for GPR-based ice thickness measurements to improve the measurement accuracy. Thus, this work can serve as a reference for future applications in similar rivers. [ABSTRACT FROM AUTHOR]

[Display omitted] Androgenetic alopecia (AGA) affects physical and mental health with limited therapeutic options. Novel materials and delivery methods have considerable potential to improve the current paradigm of treatment. In this study, we used a novel plant nanoparticle of safflower oil body (SOB) loaded with human fibroblast growth factor 10 (hFGF10) to target hair follicles and accelerate hair regeneration in AGA mice with few adverse effects. Our data revealed that the average particle size of SOB-hFGF10 was 226.73 ± 9.98 nm, with a spherical and uniform structure, and that SOB-hFGF10 was quicker to preferentially penetrate into hair follicles than hFGF2 alone. Using a mouse model of AGA, SOB-hFGF10 was found to significantly improve hair regeneration without any significant toxicity. Furthermore, SOB-hFGF10 inhibited dihydrotestosterone (DHT)-induced TNF-α, IL-1β, and IL-6 overproduction in macrophages in relation to hair follicle microinflammation, thereby enhancing the proliferation of dermal papilla cells. Overall, this study provides an applicable therapeutic method through targeting hair follicles and reducing microinflammation to accelerate hair regeneration in AGA. [ABSTRACT FROM AUTHOR]

Abstract: An investigation into the equation of state (EOS), electronic and elastic properties of Zr2SC has been conducted by first-principles pseudopotential calculations. The calculated EOS is well consistent with the recent experimental reports. The absence of band gap at the Fermi level and the finite value of the density of states at the Fermi energy reveal the metallic behavior of Zr2SC. From the variations of elastic constants with pressure, we find that hexagonal Zr2SC is most stable in the pressure range from 0 to 100GPa, which is consistent with the experimental observations. The strong hybridization of Zr 4d states, S 3p states and C 2p states and the presence of pseudogap stabilize the structure of Zr2SC. By analyzing the ratio between the bulk and shear moduli, we conclude that Zr2SC is brittle in nature. The mechanism of brittleness of Zr2SC originated from the large value of Zr atom occupying the internal parameter z. [Copyright &y& Elsevier]

Ice blasting with explosives before the spring breakup of river sections is a preventive measure for ice flooding. Based on 496 datasets on ice cover blasting with No. 2 emulsion rock explosives measured in the Mohe reach of the Heilongjiang River from 2015 to 2018, we analyzed the relationships between the blasting-crater diameter and water depth below the ice and between the blasting-crater diameter and the explosive-placement depth below the ice. Further, we analyzed the functional relationship between the explosive weight of a single blast hole and the blasting-crater diameter. Based on the above analysis we proposed an equation to calculate the minimum blasting cost for the same blasting effect. Using a 5-km section of the Heilongjiang River as an example, the proposed optimization method can save ~46% of the total blasting cost while achieving the same blasting effect. Through prototype observations of the Longdao Wharf and the Shengdan Village sections of the Mohe reach, Heilongjiang River, we confirmed that ice blasting can significantly accelerate the melting of ice. Moreover, data records showed that no significant ice-jam flooding has occurred in this section of the Heilongjiang River during the spring ice breakup period in the past five years of consecutive blasting. • The use of No. 2 rock emulsion explosives to mitigate ice jam flooding was considered. • Relationships between blasting-crater diameter and explosive weight of a single blast hole were analyzed. • An equation to calculate minimum blasting cost for the same blasting effect was developed. • The proposed method can save ~46% of the total blasting cost. [ABSTRACT FROM AUTHOR]