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Aims: Epilepsy, frequently comorbid with depression, easily develops drug resistance. Here, we investigated how dorsal raphe (DR) and its 5‐HTergic neurons are implicated in epilepsy. Methods: In mouse hippocampal kindling model, using immunochemistry, calcium fiber photometry, and optogenetics, we investigated the causal role of DR 5‐HTergic neurons in seizure of temporal lobe epilepsy (TLE). Further, deep brain stimulation (DBS) of the DR with different frequencies was applied to test its effect on hippocampal seizure and depressive‐like behavior. Results: Number of c‐fos+ neurons in the DR and calcium activities of DR 5‐HTergic neurons were both increased during kindling‐induced hippocampal seizures. Optogenetic inhibition, but not activation, of DR 5‐HTergic neurons conspicuously retarded seizure acquisition specially during the late period. For clinical translation, 1‐Hz‐specific, but not 20‐Hz or 100‐Hz, DBS of the DR retarded the acquisition of hippocampal seizure. This therapeutic effect may be mediated by the inhibition of DR 5‐HTergic neurons, as optogenetic activation of DR 5‐HTergic neurons reversed the anti‐seizure effects of 1‐Hz DR DBS. However, DBS treatment had no effect on depressive‐like behavior. Conclusion: Inhibition of hyperactivity of DR 5‐HTergic neuron may present promising anti‐seizure effect and the DR may be a potential DBS target for the therapy of TLE. [ABSTRACT FROM AUTHOR]

The raphe nuclei, the primary resource of forebrain 5-HT, play an important but heterogeneous role in regulating subcortical excitabilities. Fundamental circuit organizations of different median raphe (MR) subsystems are far from completely understood. In the present study, using cell-specific viral tracing, Ca2+ fiber photometry and epilepsy model, we map out the forebrain efferent and afferent of different MR Pet+ subpopulations and their divergent roles in epilepsy. We found that PetMR neurons send both collateral and parallel innervations to different downstream regions through different subpopulations. Notably, CA3-projecting PetMR subpopulations are largely distinct from habenula (Hb)-projecting PetMR subpopulations in anatomical distribution and topological organization, while majority of the CA3-projecting PetMR subpopulations are overlapped with the medial septum (MS)-projecting PetMR subpopulations. Further, using Ca2+ fiber photometry, we monitor activities of PetMR neurons in hippocampal-kindling seizure, a classical epilepsy model with pathological mechanisms caused by excitation-inhibition imbalance. We found that soma activities of PetMR neurons are heterogeneous during different periods of generalized seizures. These divergent activities are contributed by different projection-defined PetMR subpopulations, manifesting as increased activities in CA3 but decreased activity in Hb resulting from their upstream differences. Together, our findings provide a novel framework of MR subsystems showing that projection-defined MR Pet+ subpopulations are topologically heterogenous with divergent circuit connections and are diversely implicated in seizures. This may help in the understanding of heterogeneous nature of MR 5-HTergic subsystems and the paradox roles of 5-HTergic systems in epilepsy. • PetMR neurons send both collateral and parallel innervations to different regions through different subpopulations. • PetMR-CA3 and PetMR-Hb neurons are largely distinct subpopulations that receive divergent upstream inputs. • PetMR neurons shows heterogenous activities in seizure contributed by different projection-defined subpopulations. • PetMR-CA3 and PetMR-Hb neurons respond oppositely during generalized seizures. [ABSTRACT FROM AUTHOR]

A convenient approach of preparing silicon nanotubes (SiNTs) on a silicon substrate is described in this work in detail. Firstly, a porous silicon (PSi) slice is prepared by a galvanic displacement reaction. Then it is put into aqueous solutions of 20% (w%) ammonium fluoride and 2.5 mM cobalt nitrate for a predetermined time. The cobalt ions are reduced and the resulted cobalt particles are deposited on the PSi slice. After the cobalt particles are removed with 5 M nitric acid a plenty of SiNTs come out and exhibit disorderly on the silicon substrate, which are illustrated by scanning electron microscopy (SEM). The compositions of the SiNTs are examined by energy-dispersive X-ray spectroscopy. Based on the SEM images, a suggested mechanism is put forward to explain the generation of the SiNTs on the PSi substrate. [ABSTRACT FROM AUTHOR]

Highlights: [•] Silicon quantum dots on a silicon chip with photoluminescence are manufactured. [•] The photoluminescence is stable for stepwise chemical modifications. [•] Active N-hydroxysuccinimide esters were fabricated on such silicon quantum dots. [Copyright &y& Elsevier]

Highlights: [•] A facile approach of preparing Ag NPs/porous silicon (PSi) chip is described. [•] The principle of forming Ag NPs on PSi surface is discussed in detail. [•] The Ag NPs/PSi chip performs well in catalytic reduction of aromatic nitro groups. [Copyright &y& Elsevier]

Highlights: [•] Poly(amidoamine) dendrites are introduced onto modified graphene oxide (GO) sheets. [•] The dense amino groups favor the generation of hybrids of nano magnetite/GO. [•] The hybrids exhibit a strong catalysis on degradation of hydroquinones. [ABSTRACT FROM AUTHOR]

In numerical simulation of quenching process, the boundary conditions of temperature field and stress field are very important, in which the boundary conditions of temperature field are very complicated. In order to simulate the thermal strains, thermal stresses, residual stresses and microstructure of the steel during gas quenching by means of the numerical method, it is necessary to obtain an accurate boundary condition of temperature field. The surface heat-transfer coefficient is a key parameter. The explicit finite difference method, non-linear estimate method and the experimental relation between temperature and time during quenching have been used to solve the inverse problem of heat conduction. The relationships between surface temperature and surface heat-transfer coefficient of cylinder have been given. The non-linear surface heat-transfer coefficients include the coupled effects between phase transformation and temperature. In calculation, physical properties were treated as the function of temperature and volume fraction of constituent. The results obtained have been shown that this technique can determine effectual the surface heat-transfer coefficients during gas quenching. [Copyright &y& Elsevier]

In order to enhance the robustness of interdependent power grids and communication networks, a link addition strategy is proposed, which obeys the partial one-to-one correspondence between power nodes and communication nodes. In this method, the target value of node degree is set and then the number of addition links is determined according to its degree for each node. Our strategy aims to homogenize degree distribution of nodes. Case study on IEEE test systems based on the time-step failure model of nodes shows that the proposed method can obtain better robustness and synchronization of interdependent networks in the case of random and intentional attacks. The proposed strategy can provide guidance on current topic to improve robustness of interdependent networks. • A link addition strategy is proposed obeying partial one-to-one correspondence. • The strategy integrates node information and homogenizes degree distribution. • Results show that our strategy can obtain better robustness. [ABSTRACT FROM AUTHOR]

Epilepsy is a circuit-level brain disorder characterized by excessive or hypersynchronous epileptic seizures involving a complex epileptogenic network. Cumulative evidence suggests that the piriform cortex (PC) is a crucial site in seizure initiation, propagation, and generalization in epilepsy. The kindling model is a classic animal model of complex partial seizures with secondarily generalized tonic seizures, which is usually used for the study of epilepsy pathogenesis and preclinical anti-epilepsy drug evaluation. Various essential functions of the PC in epilepsy were discovered in the kindling model, therefore, this review focuses on discussing the role of the PC in the kindling model. We review what pathological changes happen in the PC in the kindling model, how the PC is involved in the kindling model through different interventions, and finally we also provide perspectives on some possible research directions for future studies. [ABSTRACT FROM AUTHOR]

Highlights • Extension to VCFEM is achieved through enhancements in stress functions. • A singular Voronoi cell finite element method is proposed. • Stress intensity factors of crack-tip are calculated using the least square method. • Validation of this model shows good improvement. Abstract In this paper, a new singular Voronoi cell finite element method (S-VCFEM) is proposed to study the initiation and propagation of interfacial debonding and matrix cracking in particulate reinforced composite. Composites with large-scale inclusions and cracks can be easily simulated with this model. A new assumed stress hybrid variational functional is derived from the element energy function to accommodate the interface traction reciprocity on bonded interface and the interface traction-free on debonded interface and matrix crack surface. S-VCFEM is achieved through enhancements in stress functions in the assumed stress hybrid formulation. In addition to polynomial terms and interaction terms, singular stress terms of Williams expansion are added for stress functions, which are adaptively enriched to accurately capture the crack-tip stress concentrations. After obtaining the stress field, calculation of stress intensity factors is performed, using the least square method based on stress value obtained numerically in the S-VCFEM. The efficiency of the method is verified against numerical results obtained by ABAQUS with XFEM module for the same problem considering a matrix-crack and a debonded interface. [ABSTRACT FROM AUTHOR]

A generalized method for calculating the stress intensity factor from angular deflection of light rays is proposed. The method is based on 2D digital image correlation (DIC) to measure angular deflection of light rays, however, when a specimen is subjected to loading, deformation measurement from DIC is not perfect because of the existence of small in-plane and out-of-plane motions of the test sample surface that occurred after loading. These disadvantages will lead to errors in the measured angular deflections and fracture parameters. The influence of unavoidable in-plane and out-of-plane motions is discussed, and a generalized method to eliminate them to show the pure stress gradient of the crack tip of Polymethyl Methacrylate (PMMA) is demonstrated. At the same time, the fracture parameter of stress intensity was calculated. The experimental angular deflection of light rays was compared with the theoretical angular deflection predicted by generalized model using data points in an array around the crack tip region. To show the potential and efficacy of the method, K values were obtained from experimental data during tests conducted in a PMMA three-point-bend specimen. Results show an excellent level of agreement with K values predicted from FEM, highlighting the potential of the proposed methodology. [ABSTRACT FROM AUTHOR]

An approach of loading nanomagnetites (NMs), obtained by in-situ synthesis, on graphite oxides (GO) or poly(amidoamine)-modified GO (pGO) was described in detail in this work. Compared with the GO-NM, the pGO-NM hybrids performed excellent catalysis on degradation of aqueous p-nitroaniline in surrounding air and aqueous medium with a mechanical agitation without light irradiations and additional hydrogen peroxides. These properties differed tremendously from those of most reported metallic oxide-GO hybrids. The catalytic decomposing of the p-nitroaniline was recorded by the successive measurements of an ultraviolet–visible spectrometer. The chemical modifications on GO were investigated with infrared and X-ray photoelectron spectrometers. The hybrids of GO-NM and pGO-NM are estimated with ultraviolet–visible spectrometer, X-ray diffraction, transmission electron microscopy, cyclic voltammetry measurements and thermogravimetric analyses. The experimental results showed that the dissolved oxygen and water were involved in the degradation, which provided solid evidences for the mechanism discussion. [ABSTRACT FROM AUTHOR]

Aims: Temporal lobe epilepsy (TLE), often associated with cognitive impairment, is one of the most common types of medically refractory epilepsy. Deep brain stimulation (DBS) shows considerable promise for the treatment of TLE. However, the optimal stimulation targets and parameters of DBS to control seizures and related cognitive impairment are still not fully illustrated. Methods: In the present study, we evaluated the therapeutic potential of DBS in the medial septum (MS) on seizures and cognitive function in mouse acute and chronic epilepsy models. Results: We found that DBS in the MS alleviated the severity of seizure activities in both kainic acid‐induced acute seizure model and hippocampal‐kindled epilepsy model. DBS showed antiseizure effects with a wide window of effective stimulation frequencies. The antiseizure effects of DBS were mediated by the hippocampal theta rhythm, as atropine, which reversed the DBS‐induced augmentation of the hippocampal theta oscillation, abolished the antiseizure effects of DBS. Further, in the kainic acid‐induced chronic TLE model, DBS in the MS not only reduced spontaneous seizures, but also improved behavioral performance in novel object recognition. Conclusion: DBS in the MS is a promising approach to attenuate TLE probably through entrainment of the hippocampal theta rhythm, which may be therapeutically significant for refractory TLE treatment. [ABSTRACT FROM AUTHOR]

• Extension to VCFEM is achieved through enhancements in stress functions. • A new X-VCFEM is proposed to model the interface and matrix cracking in composites. • The matrix crack propagation is determined by the maximum energy release rate. • The interface crack propagation is assessed on the base of a series of criteria. • A remeshing algorithm is constructed. In this paper, a new extended Voronoi cell finite element method (X-VCFEM), in which two new elements in the crack propagation process are proposed and a remeshing algorithm is constructed, is proposed to model the initiation and propagation of the interface crack and the matrix crack in particulate reinforced composites. In order to accurately capture crack-tip stress concentrations, some singular stress terms of Williams expansion in the vicinity of crack tips are introduced in the stress functions in X-VCFEM. The direction of the crack propagation in matrix is determined by the maximum energy release rate and the interface crack propagation along the interface or into the matrix is assessed on the base of a series of criteria relating to the critical normal stress and the critical hoop stress. Then several numerical examples are used to demonstrate the effectiveness of X-VCFEM by comparing with results obtained by the commercial software ABAQUS. At last, a numerical example is given for a complex structure with 20 randomly distributing inclusions to model the interfacial cracking and matrix cracking. It is certain that this method is a powerful way to model the interfacial and matrix damage of composites containing a great deal of inclusions and cracks. [ABSTRACT FROM AUTHOR]

• Extension to VCFEM is achieved through enhancements in stress functions. • A new extended Voronoi cell finite element method is proposed. • The direction of the crack propagation is adaptively determined in terms of the maximum energy release rate. • A remeshing strategy is constructed. • The propagation of multiple cracks in brittle materials is simulated. This paper introduces a new extended Voronoi cell finite-element method (X-VCFEM) for modelling the propagation of multiple cracks in brittle materials. The direction of the crack propagation is adaptively determined in terms of the maximum energy release rate near the crack tip, and we apply a remeshing strategy that a node at a last incremental crack tip in the crack advance process is replaced by a node pairs to realize the gradual crack propagation. In order to accurately capture crack-tip stress concentrations, some singular stress terms of Williams expansion in the vicinity of crack tips are introduced in the assumed stress hybrid formulation which also includes the polynomial terms and the reciprocal terms. Then several numerical examples are used to demonstrate the effectiveness and accuracy of X-VCFEM enriched by some singular stress terms of Williams expansion by comparing X-VCFEM results with those computed by the commercial finite element package ABAQUS or established results in the literature. At last, two numerical examples are given to simulate multiple crack propagation in brittle media. The effects of morphological distributions such as length, orientation and dispersion on the crack propagation are studied. It is obvious that the X-VCFEM has great advantage of analyzing large regions of the microstructure with multiple growing and interacting cracks. [ABSTRACT FROM AUTHOR]

Previous studies indicated the involvement of cholinergic neurons in seizure; however, the specific role of the medial septum (MS)-hippocampus cholinergic circuit in temporal lobe epilepsy (TLE) has not yet been completely elucidated. In the current study, we used magnetic resonance imaging and diffusion tensor imaging to characterize the pathological change of the MS-hippocampus circuit in 42 patients with TLE compared with 22 healthy volunteers. Using optogenetics and chemogenetics, combined with in vivo or in vitro electrophysiology and retrograde rabies virus tracing, we revealed a direct MS-hippocampus cholinergic circuit that potently attenuates seizure through driving somatostatin inhibition in animal TLE models. We found that patients with TLE with hippocampal sclerosis showed a decrease of neuronal fiber connectivity of the MS-hippocampus compared with healthy people. In the mouse TLE model, MS cholinergic neurons ceased firing during hippocampal seizures. Optogenetic and chemogenetic activation of MS cholinergic neurons (but not glutamatergic or GABAergic [gamma-aminobutyric acidergic] neurons) significantly attenuated hippocampal seizures, while specific inhibition promoted hippocampal seizures. Electrophysiology combined with modified rabies virus tracing studies showed that direct (but not indirect) MS-hippocampal cholinergic projections mediated the antiseizure effect by preferentially targeting hippocampal GABAergic neurons. Furthermore, chemogenetic inhibition of hippocampal somatostatin-positive (rather than parvalbumin-positive) subtype of GABAergic neurons reversed the antiseizure effect of the MS-hippocampus cholinergic circuit, which was mimicked by activating somatostatin-positive neurons. These findings underscore the notable antiseizure role of the direct cholinergic MS-hippocampus circuit in TLE through driving the downstream somatostatin effector. This may provide a better understanding of the changes of the seizure circuit and the precise spatiotemporal control of epilepsy. [ABSTRACT FROM AUTHOR]

Urban coach cabin is an important indoor environment for long journey, formaldehyde (HCHO) is a carcinogenic gas and damages indoor air quality of cabins. In order to control the HCHO pollution, the air samples inside cabins were analysed with a thermally desorbed gas chromatograph, and the HCHO diffusion was simulated with a methodology of computational fluid dynamics (CFD). Results show that through the experimental monitoring, the HCHO pollution level range from 33.6 to 142.3 μg/m3, decrease quickly with time, and the attenuation trendline is univariate cubic equation. Through the CFD simulation, the indoor temperature and HCHO level of cabin front and rear ends are higher than ones of other areas for the insufficient air supply and the unreasonable arrangement of air exhaust outlet. Moreover, through the CFD simulation, the HCHO level decreases with height growth of breathing zone and increasing air supply speed, and fresh air lead to diffusion of HCHO pollution from cabin seat area to the surrounding area. Through the CFD simulation, the HCHO pollution under the wind speeds of 3~5 m/s is higher than the HCHO limit level from indoor air standard of China vehicles, which shows that the HCHO emission of cabin seat has an important impact on airborne HCHO pollution inside vehicle cabins. [ABSTRACT FROM AUTHOR]

Temporal lobe epilepsy (TLE) is the most common type of epilepsy and is often medically refractory. Previous studies suggest that selective pharmaco-genetic inhibition of pyramidal neurons has therapeutic value for the treatment of epilepsy, however there is a risk of disrupting normal physical functions. Here, we test whether pharmaco-genetic activation of parvalbumin neurons, which are transgenetically transduced with the modified muscarinic receptor hM3Dq can attenuate TLE. We found that pharmaco-genetic activation of hippocampal parvalbumin neurons in epileptogenic zone not only significantly extends the latency to different seizure stages and attenuates seizure activities in acute seizure model, but also greatly alleviates the severity of seizure onsets in two chronic epilepsy models. This manipulation did not affect the normal physical function evaluated in various cognitive tasks. Further, the activation of parvalbumin neurons produced an inhibition on parts of surrounding pyramidal neurons, and the direct inactivation of pyramidal neurons via the viral expression of a modified muscarinic receptor hM4Di produced a similar anti-ictogenic effect. Interestingly, pharmaco-genetic inactivation of pyramidal neurons was more sensitive to impair cognitive function. Those data demonstrated that pharmaco-genetic seizure attenuation through targeting parvalbumin neurons rather than pyramidal neurons may be a novel and relatively safe approach for treating refractory TLE. [ABSTRACT FROM AUTHOR]

Detection of the crack in an object is a critical problem for the health monitoring of a transparent object. The real-time and quantitative measurement of the crack-tip stress intensity factor (SIF) remains an open issue. In this paper, an approach for real-time and quantitative measurement for the SIFs of a Mode I crack is presented based on digital holographic interferometry (DHI). A transmission digital holographic system is established to measure the phase difference of an object wave during loading. The expression to achieve the SIF from the phase difference is formulated. To enhance the accuracy of measurement, calibrated phase unwrapping based on least-squares and iteration and median filtering is applied to retrieve the actual phase from the noisy wrapped one. The SIFs of the Mode I crack in a transparent polymethyl methacrylate (PMMA) specimen are measured by this approach. The results are compared with the theoretical ones to demonstrate the feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

In this paper, a simultaneous measurement method of stress-optic constant and stress field of transparent plate is presented based on digital holographic interferometry. An image-plane digital holographic system is used to capture holograms and measure phase difference of object wave at different loading states. The relationship among the phase difference, the stress-optic constant and stress of transparent plate is given. The stress-optic constant and stress field of a polymethyl methacrylate (PMMA) specimen with a hole under uniform tensile force are measured by this method. The experimental results are in accordance with the existed and theoretical ones. [ABSTRACT FROM AUTHOR]