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Epilepsy is a common chronic brain disorder. Detecting epilepsy by observing electroencephalography (EEG) is the main method neurologists use, but this method is time-consuming. EEG signals are non-stationary, nonlinear, and often highly noisy, so it remains challenging to recognize epileptic EEG signals more accurately and automatically. This paper proposes a novel classification system of epileptic EEG signals for single-channel EEG based on the attention network that integrates time-frequency and nonlinear dynamic features. The proposed system has three novel modules. The first module constructs the Hilbert spectrum (HS) with high time-frequency resolution into a two-channel parallel convolutional network. The time-frequency features are fully extracted by complementing the high-dimensional features of the two branches. The second module constructs a grayscale recurrence plot (GRP) that contains more nonlinear dynamic features than traditional RP, fed into the residual-connected convolution module for effective learning of nonlinear dynamic features. The third module is the feature fusion module based on a self-attention mechanism to assign optimal weights to different types of features and further enhance the information extraction capability of the system. Therefore, the system is named HG-SANet. The results of several classification tasks on the Bonn EEG database and the Bern-Barcelona EEG database show that the HG-SANet can effectively capture the contribution degree of the extracted features from different domains, significantly enhance the expression ability of the model, and improve the accuracy of the recognition of epileptic EEG signals. The HG-SANet can improve the diagnosis and treatment efficiency of epilepsy and has broad application prospects in the fields of brain disease diagnosis. [ABSTRACT FROM AUTHOR]

This exploration employs the generalized supremum augmented Dickey-Fuller (GSADF) approach to explore whether there are digital tech bubbles in China. The empirical results suggest the existence of multiple digital tech bubbles, which are mostly accompanied by an excessive rise. However, the appearance of digital tech bubbles is curbed since 2016, mainly due to the increasing mature regulations in relevant fields. Besides, bubbles in different digital technologies are similar during the same period, which could be attributed to the close relationships among them. Additionally, we further investigate the factors influencing the explosive behaviours, and find that the Chinese stock market positively affects digital tech bubbles, while economic policy uncertainties and situations negatively influence such explosive behaviors. In the context of the new round of scientific and technological revolution and industrial transformation, these conclusions provide valuable implications to achieve the target of constructing a "Digital China" by becoming moderately cautious about potential bubbles in the digital tech industry. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Hot Universe Baryon Surveyor (HUBS) is a proposed space-based X-ray telescope for detecting X-ray emissions from the hot gas content in our universe. With its unprecedented spatially-resolved high-resolution spectroscopy and large field of view, the HUBS mission will be uniquely qualified to measure the physical and chemical properties of the hot gas in the interstellar medium, the circumgalactic medium, the intergalactic medium, and the intracluster medium. These measurements will be valuable for two key scientific goals of HUBS, namely to unravel the AGN and stellar feedback physics that governs the formation and evolution of galaxies, and to probe the baryon budget and multi-phase states from galactic to cosmological scales. In addition to these two goals, the HUBS mission will also help us solve some problems in the fields of galaxy clusters, AGNs, diffuse X-ray backgrounds, supernova remnants, and compact objects. This paper discusses the perspective of advancing these fields using the HUBS telescope. [ABSTRACT FROM AUTHOR]

A multicomponent tandem arylation reaction was established under transition‐metal‐free conditions to synthesize structurally diverse imidazo[1,2‐a]pyridines. As N,N‐dimethylaniline is not only a reactant but also a methylation reagent, its use affords an alternative route for methylation. This approach features mild reaction conditions and good functional group tolerance, providing 29 compounds in acceptable yields. [ABSTRACT FROM AUTHOR]

Methionine is the only one of the essential amino acids that contain sulfur, widely used as a feed additive in agriculture. In this study, the availability of 5-methyl-tetrahydrofolate was confirmed as the main limitation in the complex multibranched biosynthetic pathway of L-methionine. The cycle of one-carbon units was thoroughly investigated and modified to supply 5-methyl-tetrahydrofolate for L-methionine production, such as enhancing the supply of precursor, expediting the conversion rate of the cycle, introducing exogenous serine hydroxymethyltransferase and increasing pool size of one-carbon units carrier. The final strain MYA/pAmFA-4 was able to produce 20.89 g/L L-methionine by fed-batch fermentation, which was the highest titer reported in the literatures. This study is instructive for other metabolites biosynthesized needing one-carbon units or having a complex multibranched biosynthetic pathway. [ABSTRACT FROM AUTHOR]

Advances in thin film light-emitting devices have fueled the rapid growth of a new class of solid-state lighting devices, featuring low fabrication cost, high quantum efficiency, and broadband spectrum coverage, etc. In contrast to the conventional inorganic semiconductors that rely on lattice matched high crystalline quality substrate, solution processable thin films eliminate the dependence on the substrate, which is highly desired for the ease and versatility of integrations with foreign medium. By taking this advantage, this work developed an ultracompact solution to control the directionality of thin film emitters using integrated dielectric metasurface through one step spin-coating process. As a proof of concept, directional emissions from perovskite nanocrystal thin film, including collimated light emissions and two-dimensional beam steering, are experimentally demonstrated. Notably, our approach, where light emitters were integrated on the back side of substrate after the fabrication of metasurface, judiciously avoids any potential degradation of material optical quality caused by the multi-step nanofabrication. Therefore, it can serve as a generalized scheme to engage the advantageous properties of dielectric metasurface, including the compactness, high efficiency, and beam controllability with the emerging thin film light-emitting diodes (LEDs), which is applicable to a wide range of solution processable materials, including organic light-emitting diodes, quantum-dot light emitting diodes, polymer LEDs, and perovskite LEDs, opening up new pathways to develop low-cost and ultra-compact solid state light sources with versatile beams characteristics. [ABSTRACT FROM AUTHOR]

Cardio-cerebrovascular diseases are the leading cause of death worldwide and there is currently no optimal treatment plan. Chinese herbal medicine injection (CHI) is obtained by combining traditional Chinese medicine (TCM) theory and modern production technology. It retains some characteristics of TCM while adding injection characteristics. CHI has played an important role in the treatment of critical diseases, especially cardio-cerebrovascular diseases, and has shown unique therapeutic advantages. TCMs that promote blood circulation and remove blood stasis, such as Salvia miltiorrhiza, Carthami flos, Panax notoginseng, and Chuanxiong rhizoma, account for a large proportion of CHIs of cardiocerebrovascular disease. CHI is used to treat cardio-cerebrovascular diseases and has potential pharmacological activities such as anti-platelet aggregation, anti-inflammatory, anti-fibrosis, and anti-apoptosis. However, CHIs have changed the traditional method of administering TCMs, and the drugs directly enter the bloodstream, which may produce new pharmacological effects or adverse reactions. This article summarizes the clinical application, pharmacological effects, and mechanism of action of different varieties of CHIs commonly used in the treatment of cardio-cerebrovascular diseases, analyzes the causes of adverse reactions, and proposes suggestions for rational drug use and pharmaceutical care methods to provide a reference for the rational application of CHIs for cardio-cerebrovascular diseases. [ABSTRACT FROM AUTHOR]

Achieving nanoconfinement-controlled synthesis of nanoplatelets (NPLs) via solution process under ambient condition remains a challenge. In this work, we developed a general ligand-induced strategy to synthesize colloidal stable all-inorganic semiconductor NPLs with controllable lateral dimensions. By introducing certain metal salts (cations: Zn2+ and In3+, anions: NO3−, BF4−, or triflate OTf−), wurtzite-structured (WZ-) CdS, CdSe, CdTe, and alloy Cd1−xZnxSe NPLs were directly synthesized in solution through the controlled diffusion of magic-size clusters (MSCs) at room temperature. Mechanism studies revealed that destabilization of MSCs and nanoconfined growth in templates facilitated the formation of NPLs. The present study not only provides a new synthetic route for the preparation of NPLs but also helps to provide insight into their probable formation mechanism and presents an important advance toward the rational design of functional nanomaterials. [ABSTRACT FROM AUTHOR]

C42H27MnN5O9·2H2O, triclinic, P 1 ‾ (no. 2), a = 12.4250(8) Å, b = 12.7259(8) Å, c = 14.2946(9) Å, α = 64.102(2)°, β = 79.774(2)°, γ = 62.453(2)°, V = 1801.9(2) Å3, Z = 2, Rgt(F) = 0.0344, wRref(F2) = 0.0951, T = 150 K. [ABSTRACT FROM AUTHOR]

Background: Shenxiong Glucose Injection (SGI) is a traditional Chinese medicine formula composed of ligustrazine hydrochloride and Danshen (Radix et rhizoma Salviae miltiorrhizae; Salvia miltiorrhiza Bunge, Lamiaceae). Our previous studies and others have shown that SGI has excellent therapeutic effects on myocardial ischemia (MI). However, the potential mechanisms of action have yet to be elucidated. This study aimed to explore the molecular mechanism of SGI in MI treatment. Methods: Sprague-Dawley rats were treated with isoproterenol (ISO) to establish the MI model. Electrocardiograms, hemodynamic parameters, echocardiograms, reactive oxygen species (ROS) levels, and serum concentrations of cardiac troponin I (cTnI) and cardiac troponin T (cTnT) were analyzed to explore the protective effect of SGI on MI. In addition, a model of oxidative damage and apoptosis in human umbilical vein endothelial cells (HUVECs) was established using CoCl2. Cell viability, Ca2+ concentration, mitochondrial membrane potential (MMP), apoptosis, intracellular ROS, and cell cycle parameters were detected in the HUVEC model. The expression of apoptosis-related proteins (Bcl-2, Caspase-3, PARP, cytoplasmic and mitochondrial Cyt-c and Bax, and p-ERK1/2) was determined by western blotting, and the expression of cleaved caspase-3 was analyzed by immunofluorescence. Results: SGI significantly reduced ROS production and serum concentrations of cTnI and cTnT, reversed ST-segment elevation, and attenuated the deterioration of left ventricular function in ISO-induced MI rats. In vitro, SGI treatment significantly inhibited intracellular ROS overexpression, Ca2+ influx, MMP disruption, and G2/M arrest in the cell cycle. Additionally, SGI treatment markedly upregulated the expression of anti-apoptotic protein Bcl-2 and downregulated the expression of pro-apoptotic proteins p-ERK1/2, mitochondrial Bax, cytoplasmic Cyt-c, cleaved caspase-3, and PARP. Conclusion: SGI could improve MI by inhibiting the oxidative stress and apoptosis signaling pathways. These findings provide evidence to explain the pharmacological action and underlying molecular mechanisms of SGI in the treatment of MI. [ABSTRACT FROM AUTHOR]

Background. Gastric cancer (GC) is one of the gastrointestinal tumors with the highest mortality rate. The number of GC patients is still high. As a way of iron-dependent programmed cell death, ferroptosis activates lipid peroxidation and accumulates large reactive oxygen species. The role of ferroptosis in GC prognosis was underrepresented. The objective was to investigate the role of ferroptosis-related genes (FRGs) in the prognosis and development of GC. Methods. Datasets of GC patients were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) database that include clinical information and RNA seq data. Through nonnegative matrix factorization (NMF) clustering, we identified and unsupervised cluster analysis of the expression matrix of FRGs. And we constructed the co-expression network between genes and clinical characteristics by consensus weighted gene co-expression network analysis (WGCNA). The prognostic model was constructed by univariate and multivariate regression analysis. The potential mechanisms of development and prognosis in GC were explored by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, gene ontology (GO), tumor immune microenvironment (TIME), and tumor mutation burden (TMB). Results. Two molecular subclusters with different expression patterns of FRGs were identified, which have significantly different survival states. Ferroptosis subcluster-related modular genes were identified by WGCNA. Based on 8 ferroptosis subcluster-related modular genes (collagen triple helix repeat containing 1 (CTHRC1), podoplanin (PDPN), procollagen-lysine,2-oxoglutarate 5-dioxygenase 2 (PLOD2), glutamine-fructose-6-phosphate transaminase 2 (GFPT2), ATP-binding cassette subfamily A member 1 (ABCA1), G protein-coupled receptor 176 (GPR176), serpin family E member 1 (SERPINE1), dual specificity phosphatase 1 (DUSP1)) and clinicopathological features, a nomogram was constructed and validated for their predictive efficiency on GC prognosis. Through receiver operating characteristic (ROC) analysis, the results showed that the area under the curve (AUC) of 1-, 3-, and 5-year survival were 0.721, 0.747, and 0.803, respectively, indicating that the risk-scoring model we constructed had good prognosis efficacy in GC. The degree of immune infiltration in high-risk group was largely higher than low-risk group. It indicated that the immune cells have a good response in high-risk group of GC. The TMB of high-risk group was higher, which could generate more mutations and was more conducive to the body's resistance to the development of cancer. Conclusion. The risk-scoring model based on 8 ferroptosis subcluster-related modular genes has shown outstanding advantages in predicting patient prognosis. The interaction of ferroptosis in GC development may provide new insights into exploring molecular mechanisms and targeted therapies for GC patients. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Capital Normal University (Natural Science Edition) is the property of Journal of Capital Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diabetes is closely related to the occurrence of endometrial cancer (EC) and its poor prognosis. However, there is no effective clinical treatment for EC patients with diabetes (patientEC+/dia+). To explore new therapeutic targets, Ishikawa is cultured with high glucose (IshikawaHG) mimicking hyperglycemia in patientEC+/dia+. Subsequently, it is discovered that IshikawaHG exhibits glucose metabolic reprogramming characterized by increased glycolysis and decreased oxidative phosphorylation. Further, pyruvate dehydrogenase kinase 1 (PDK1) is identified to promote glycolysis of IshikawaHG by proteomics. Most importantly, JX06, a novel PDK1 inhibitor combined metformin (Met) significantly inhibits IshikawaHG proliferation though IshikawaHG is resistant to Met. Furthermore, a reduction‐sensitive biodegradable polymer is adopted to encapsulate JX06 to form nanoparticles (JX06‐NPs) for drug delivery. It is found that in vitro JX06‐NPs have better inhibitory effect on the growth of IshikawaHG as well as patient‐derived EC cells (PDC) than JX06. Additionally, it is found that JX06‐NPs can accumulate to the tumor of EC‐bearing mouse with diabetes (miceEC+/dia+) after intravenous injection, and JX06‐NPs combined Met can significantly inhibit tumor growth of miceEC+/dia+. Taken together, the study demonstrates that the combination of JX06‐NPs and Met can target the cancer metabolism plasticity, which significantly inhibits the growth of EC, thereby provides a new adjuvant therapy for patientsEC+/dia+. [ABSTRACT FROM AUTHOR]

The poor stability of halide perovskite nanocrystals (NCs) has severely hindered future practical application. Herein, we proposed a facile and effective ligand modification route to synthesize stable CsPbBr3 nanocrystals by introducing a double-terminal ligand, namely 4,4′-Azobis(4-cyanovalericacid) (CA), to replace the conventional oleic acid (OA) ligand at room temperature. The as-synthesized CsPbBr3-CA not only possesses high photoluminescence quantum yield (72%) related to the reduced trap defects, but also shows significantly improved stability exposure to water, ethanol, light, and/or heat benefiting from the CA ligand anchored to NC surfaces tightly. The photoluminescence intensity of CsPbBr3-CA maintains about 80% and 75% of its initial emission intensity after immersed in water or ethanol for 360 min, respectively, whereas that of the CsPbBr3-OA was quenched completely within a few minutes. Moreover, an all-inorganic white light-emitting diode (LED) covered 126% National Television System Committee (NTSC) standard and 92% Rec.2020 standard was fabricated by combining the green CsPbBr3-CA and commercial red-emitting K2SiF6:Mn4+ (KSF) phosphors onto a blue LED chip. Thus, the presented work initiates the development of the room temperature preparation of high quality CsPbBr3 and shows prospect for next-generation displays. [ABSTRACT FROM AUTHOR]

Blinking fluorophore perovskite nanocrystals (NCs) were employed to image the fine structure of the polystyrene (PS) electrospun fibers. The conditions of CsPbBr3 NCs embedded and dispersed into PS were investigated and optimized. The stochastic optical reconstruction microscopy is employed to visualize the fine structure of the resulted CsPbBr3@PS electrospun fibers at sub-diffraction limit. The determined resolution in the reconstructed nanoscopic image is around 25.5 nm, which is much narrower than that of conventional fluorescence image. The complex reticulation and multicompartment in bead sub-diffraction-limited structures of CsPbBr3@PS electrospun fibers were successfully mapped with the help of the stochastic blinking properties of CsPbBr3 NCs. This work demonstrated the potential applications of CsPbBr3 perovskite NCs in super-resolution fluorescence imaging to reconstruct the sub-diffraction-limited features of polymeric material. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of polymers to replace oleylamine (OLA) and oleic acid (OA) as ligands for perovskite nanocrystals is an effective strategy to improve their stability and durability especially for the solution-based processing. Herein, we report a mechanosynthesis of lead bromide perovskite nanoparticles (NPs) stabilized by partially hydrolyzed poly(methyl methacrylate) (h-PMMA) and high-molecular-weight highly-branched poly(ethylenimine) (PEI-25K). The as-synthesized NP solutions exhibited green emission centered at 516 nm, possessing a narrow full-width at half-maximum of 17 nm and as high photoluminescence quantum yield (PL QY) as 85%, while showing excellent durability and resistance to polar solvents, e.g., methanol. The colloids of polymer-stabilized NPs were directly processable to form stable and strongly-emitting thin films and solids, making them attractive as gain media. Furthermore, the roles of h-PMMA and PEI-25K in the grinding process were studied in depth. The h-PMMA can form micelles in the grinding solvent of dichloromethane to act as size-regulating templates for the growth of NPs. The PEI-25K with large amounts of amino groups induced significant enrichment of PbBr2 in the reaction mixture, which in turn caused the formation of CsPb2Br5-mPbBr2 and CsPbBr3-Cs4PbBr6-nCsBr NPs. The presence of CsPbBr3-Cs4PbBr6-nCsBr NPs was responsible for the high PL QY, as the Cs4PbBr6 phase with a wide energy bandgap can passivate the surface defects of the CsPbBr3 phase. This work describes a direct and facile mechanosynthesis of polymer-coordinated perovskite NPs and promotes in-depth understanding of the formation and phase conversion for perovskite NPs in the grinding process. [ABSTRACT FROM AUTHOR]

Copyright of Boletín de la Asociación Española de Entomología is the property of Asociacion Espanola de Entomologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Inorganic halide perovskites such as cesium lead iodide (CsPbI3) have drawn tremendous attention, as their tunable band gaps are desirable for solar cells as well as light emitting diodes. However, due to their low Goldschmidt tolerance factor, the cubic phase of bulk CsPbX3—the variant with desirable band gap—is not stable in ambient, especially in humid air. Besides, the low solubility of CsX in precursor makes it difficult to control the film thickness and morphology of CsPbX3, which becomes another obstacle for the practical application of inorganic perovskite. Here, we report a polymer assisted deposition of high-quality CsPbI2Br film by spin-coating a polymer-blended CsPbI2Br precursor. The long-chained polymer increases the viscosity of the solution, which enables us to achieve a ca. 700-nm thick film with a low solution concentration of CsPbI2Br. Moreover, the polymer network helps to regulate the crystallization process and provides more crystallization sites for perovskite film, reducing grain size and thus improving the film coverage. Perovskite solar cells with the polymer network exhibit improved efficiency and reproducibility (0.72% standard deviation). Moreover, the device demonstrates excellent robustness against moisture and oxygen, and maintains 90% of its initial power conversion efficiency (PCEs) after aging 4 months in ambient conditions. The conception of polymer incorporation into inorganic perovskite films paves a way to further increase the performance, stability and reproducibility of inorganic perovskite devices. [ABSTRACT FROM AUTHOR]

In this study, we investigated the electronic character of protein environment in enzymatic processes by performing all-electron QM calculations based on the fragment molecular orbital (FMO) method. By introducing a new computational strategy combining all-electron QM analysis with ab initio QM/MM modeling, we investigated the details of molecular interaction energy between a reactive substrate and amino acid residues at a catalytic site. For a practical application, we selected the chorismate mutase catalyzed reaction as an example. Because the computational time required to perform all-electron QM reaction path searches was very large, we employed the ab initio QM/MM modeling technique to construct reliable reaction profiles and performed all-electron FMO calculations for the selected geometries. The main focus of the paper is to analyze the details of electrostatic stabilization, which is considered to be the major feature of enzymatic catalyses, and to clarify how the electronic structure of proteins is polarized in response to the change in electron distribution of the substrate. By performing interaction energy decomposition analysis from a quantum chemical viewpoint, we clarified the relationship between the location of amino acid residues on the protein domain and the degree of electronic polarization of each residue. In particular, in the enzymatic transition state, Arg7, Glu78, and Arg90 are highly polarized in response to the delocalized electronic character of the substrate, and as a result, a large amount of electrostatic stabilization energy is stored in the molecular interaction between the enzyme and the substrate and supplied for transition state stabilization. [ABSTRACT FROM AUTHOR]

Many evolutionary computation (EC) methods have been used to solve feature selection problems and they perform well on most small-scale feature selection problems. However, as the dimensionality of feature selection problems increases, the solution space increases exponentially. Meanwhile, there are more irrelevant features than relevant features in datasets,which leads to many local optima in the huge solution space. Therefore, the existing EC methods still suffer from the problem of stagnation in local optima on large-scale feature selection problems. Furthermore, large-scale feature selection problems with different datasets may have different properties. Thus, it may be of low performance to solve different large-scale feature selection problems with an existing EC method that has only one candidate solution generation strategy (CSGS). In addition, it is time-consuming to find a suitable EC method and corresponding suitable parameter values for a given largescale feature selection problem if we want to solve it effectively and efficiently. In this article, we propose a self-adaptive particle swarm optimization (SaPSO) algorithm for feature selection, particularly for largescale feature selection. First, an encoding scheme for the feature selection problem is employed in the SaPSO. Second, three important issues related to self-adaptive algorithms are investigated. After that, the SaPSO algorithm with a typical self-adaptive mechanism is proposed. The experimental results on 12 datasets show that the solution size obtained by the SaPSO algorithm is smaller than its EC counterparts on all datasets. The SaPSO algorithm performs better than its non-EC and EC counterparts in terms of classification accuracy not only on most training sets but also on most test sets. Furthermore, as the dimensionality of the feature selection problem increases, the advantages of SaPSO become more prominent. This highlights that the SaPSO algorithm is suitable for solving feature selection problems, particularly large-scale feature selection problems. [ABSTRACT FROM AUTHOR]

The globus pallidus occupies a critical position in the indirect pathway of the basal ganglia motor control system. Hyperpolarization-activated cyclic-nucleotide gated (HCN) channels play an important role in the modulation of neuronal excitability. In vivo extracellular single unit recording, behavioral test and immunohistochemistry were performed to explore the possible modulation of endogenous HCN channels in the globus pallidus under parkinsonian states. In MPTP parkinsonian mice, micro-pressure application of the selective HCN channel antagonist, ZD7288, decreased the firing rate in 10 out of the 28 pallidal neurons, while increased the firing rate in another 15 out of the 28 neurons. In 6-OHDA parkinsonian rats, ZD7288 also bidirectionally regulated the spontaneous firing activity of the globus pallidus neurons. The proportion of pallidal neurons with ZD7288-induced slowing of firing rate tended to reduce in both parkinsonian animals. Morphological studies revealed a weaker staining of HCN channels in the globus pallidus under parkinsonian state. Finally, behavioral study demonstrated that intrapallidal microinjection of ZD7288 alleviated locomotor deficits in MPTP parkinsonian mice. These results suggest that endogenous HCN channels modulate the activities of pallidal neurons under parkinsonian states. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy (SMA) are chronic, progressive, and age-associated neurological disorders characterized by neuronal deterioration in specific brain regions. Although the specific pathological mechanisms underlying these disorders have remained elusive, ion channel dysfunction has become increasingly accepted as a potential mechanism for neurodegenerative diseases. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by the HCN1-4 gene family and conduct the hyperpolarization-activated current (I h). These channels play important roles in modulating cellular excitability, rhythmic activity, dendritic integration, and synaptic transmission. In the present review, we first provide a comprehensive picture of the role of HCN channels in PD by summarizing their role in the regulation of neuronal activity in PD-related brain regions. Dysfunction of I h may participate in 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity and represent a pathogenic mechanism in PD. Given current reports of the critical role of HCN channels in neuroinflammation and depression, we also discussed the putative contribution of HCN channels in inflammatory processes and non-motor symptoms in PD. In the second section, we summarize how HCN channels regulate the formation of β-amyloid peptide in AD and the role of these channels in learning and memory. Finally, we briefly discuss the effects of HCN channels in ALS and SMA based on existing discoveries. [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskite quantum dots (QDs) have been a promising candidate for optoelectronic devices in recent years, such as light-emitting diodes, photodetectors and solar cells, owing to their superb optoelectronic properties. Still, the stability issue of nanocrystals is a bottleneck for their practical application. Herein, we report a facile method for the synthesis of a series of phosphine ligand modified CsPbBr3 QDs with high PL intensity. By introducing organic phosphine ligands, the tolerance of CsPbBr3 QDs to ethanol, water and UV light was dramatically improved. Moreover, the phosphine ligand modified QD films deposited on the glass subtracts exhibit superior PL intensity and optical stability to those of pristine QD based films. [ABSTRACT FROM AUTHOR]

We study the dynamics of the l norm coherence in a two-dimensional quantum walk on finite lattices with four-dimensional (4D) and two-dimensional (2D) coins. It is observed that the boundaries suppress the growth of coherence of both the whole system and the position subsystem. The coherence of the quantum walk with a 2D coin is larger than that of the quantum walk with a 4D coin when it stabilizes after a number of steps. We also analyze the influence of two kinds of noise, i.e., broken links and lattice congestion, on the coherence of a bounded quantum walk. Experimental results show that both the broken links and the lattice congestion with low probability slightly increase the coherence of the whole system and the position subsystem. However, a high noise level significantly suppresses the growth of coherence, especially for static noise. The coherence of the coin subsystem is also analyzed and we find that the boundaries result in a large fluctuation of coherence of the coin subsystem. [ABSTRACT FROM AUTHOR]

Copyright of Eastern-European Journal of Enterprise Technologies is the property of PC TECHNOLOGY CENTER and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The dynamics of neuronal excitability determine the neuron’s response to stimuli, its synchronization and resonance properties and, ultimately, the computations it performs in the brain. We investigated the dynamical mechanisms underlying the excitability type of dopamine (DA) neurons, using a conductance-based biophysical model, and its regulation by intrinsic and synaptic currents. Calibrating the model to reproduce low frequency tonic firing results in N-methyl-D-aspartate (NMDA) excitation balanced by γ-Aminobutyric acid (GABA)-mediated inhibition and leads to type I excitable behavior characterized by a continuous decrease in firing frequency in response to hyperpolarizing currents. Furthermore, we analyzed how excitability type of the DA neuron model is influenced by changes in the intrinsic current composition. A subthreshold sodium current is necessary for a continuous frequency decrease during application of a negative current, and the low-frequency “balanced” state during simultaneous activation of NMDA and GABA receptors. Blocking this current switches the neuron to type II characterized by the abrupt onset of repetitive firing. Enhancing the anomalous rectifier Ih current also switches the excitability to type II. Key characteristics of synaptic conductances that may be observed in vivo also change the type of excitability: a depolarized γ-Aminobutyric acid receptor (GABAR) reversal potential or co-activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) leads to an abrupt frequency drop to zero, which is typical for type II excitability. Coactivation of N-methyl-D-aspartate receptors (NMDARs) together with AMPARs and GABARs shifts the type I/II boundary toward more hyperpolarized GABAR reversal potentials. To better understand how altering each of the aforementioned currents leads to changes in excitability profile of DA neuron, we provide a thorough dynamical analysis. Collectively, these results imply that type I excitability in dopamine neurons might be important for low firing rates and fine-tuning basal dopamine levels, while switching excitability to type II during NMDAR and AMPAR activation may facilitate a transient increase in dopamine concentration, as type II neurons are more amenable to synchronization by mutual excitation. [ABSTRACT FROM AUTHOR]

Degradation behavior of ethylthionocarbamate by activated sludge coupled with interior microelectrolysis (ASCIE) was investigated. Degradation kinetics and removal efficiency of ethylthionocarbamate were also discussed in comparison with traditional activated sludge (AS) and interior microelectrolysis (IE), respectively. The results showed that the degradation rate decreased sharply when most ethylthionocarbamate was removed from the solution of these three different processes, the degradation rate of ethylthionocarbamate was ranked from high to low as ASCIE > IE > AS, and the corresponding maximum degradation rate was 5.705, 4.185, and 1.90 mg/(L d), respectively. The degradation of ethylthionocarbamate under these three different processes can be accurately described by first-order exponential decay kinetics. [ABSTRACT FROM PUBLISHER]

By shunting a susceptance at the middle of the branch of a conventional Wilkinson power divider, the size can be reduced and the harmonic components can be suppressed. Further, miniaturization can be achieved by optimal layout of the internal area of the conventional power divider. In this article, simple design methods to implement miniaturized Wilkinson power dividers with harmonic suppressions are presented. To validate the design methodology, two power divider prototypes are optimally designed and examined from electromagnetic simulations and experiments. As compared to conventional types, the circuit sizes of the demonstrators are effectively reduced to 15.6 and 24.98%, respectively, and the spurious suppressions are over 20 dB at the desired harmonic frequencies. Meanwhile, the mechanisms of spurious suppression are studied herein. The achieved performance simply confirms the presented design methodology. [ABSTRACT FROM AUTHOR]

We investigate the biophysical and dynamic mechanisms of generation of subthreshold amplitude and phase resonance in response to sinusoidal input currents in two-dimensional models of quadratic type. These models feature a parabolic voltage nullcline and a linear nullcline for the recovery gating variable, capturing the interplay of the so-called resonant currents (e.g., hyperpolarization-activated mixed-cation inward and slow potassium) and amplifying currents (e.g., persistent sodium) in biophysically realistic parameter regimes. These currents underlie the generation of resonance in medial entorhinal cortex layer II stellate cells and CA1 pyramidal cells. We show that quadratic models exhibit nonlinear amplifications of the voltage response to sinusoidal inputs in the resonant frequency band. These are expressed as an increase in the impedance profile as the input amplitude increases. They are stronger for values positive than negative to resting potential and are accompanied by a shift in the phase profile, a decrease in the resonant and phase-resonant frequencies, and an increase in the sharpness of the voltage response. These effects are more prominent for smaller values of 휖 (larger levels of the time scale separation between the voltage and the resonant gating variable) and for values of the resting potential closer to threshold for spike generation. All other parameter fixed, as 휖 increases the voltage response becomes 'more linear'; i.e., the nonlinearities are present, but 'ignored'. In addition, the nonlinear effects are strongly modulated by the curvature of the parabolic voltage nullcline (partially reflecting the effects of the amplifying current) and the slope of the resonant current activation curve. Following the effects of changes in the biophysical conductances of realistic conductance-based models through the parameters of the quadratic model, we characterize the qualitatively different effects that resonant and amplifying currents have on the nonlinear properties of the voltage response. We identify different classes of resonant currents, represented by h- and slow potassium, according to whether they enhance (h-) or attenuate (slow potassium) the nonlinear effects. Finally, we use dynamical systems tools to investigate the dynamic mechanisms of generation of resonance and phase-resonance. We show that the nonlinear effects on the voltage response (e.g., amplification of the voltage response in the resonant frequency band and shifts in the resonant and phase-resonant frequencies) result from the ability of limit cycle trajectories to follow the unstable (right) branch of the voltage nullcline for a significant amount of time. This is a canard-related mechanism that has been shown to underlie the generation of intrinsic subthreshold oscillations in quadratic type models such as medial entorhinal cortex stellate cells. Overall, our results highlight the complexity of the voltage response to oscillatory inputs in nonlinear models and the roles that resonant and amplifying currents have in shaping these responses. [ABSTRACT FROM AUTHOR]

The black hole mass function of supermassive black holes describes the evolution of the distribution of black holemass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for constraining theoretical models of their evolution. In this paper, we discuss methods for estimating the black hole mass function, including their advantages and disadvantages. We also review the results of using these methods for estimating the mass function of both active and inactive black holes. In addition, we review current theoretical models for the growth of supermassive black holes that predict the black hole mass function. We conclude with a discussion of directions for future research which will lead to improvement in both empirical and theoretical determinations of the mass function of supermassive black holes. [ABSTRACT FROM AUTHOR]

A unipolar binary bidirectional associative memory (UBBAM) has been designed to associate input and output vectors in a manner of a content addressable memory. The neural network thus formed does not require inhibitory neurons and is well suited for optoelectronic implementa tion. The performance of the UBBAM has been shown to match that of the original BAM. The key device in the implementation of the UBBAM is a Smart Advanced Spatial Light Modulator (SASLM1), a ferroelectric liquid crystal (FELC) SLM driven by a silicon CMOS backplane. The smart pixel of the SASLM serves as a local processing unit which sets the state of its FELC modula tor according to some function of the optical signals incident upon the pixel's photodetector. The ac tion of each smart pixel is hence akin to a neuron's soma, and a matrix of such smart pixels therefore forms a powerful parallel processing hardware, significant in representing neuron fields, in real time, with minimal off-chip control and processing. The UBBAM model, the SASLM1 smart pixels and a proposed optical system will be described in this paper. [ABSTRACT FROM PUBLISHER]

This letter presents a planar power divider with an effective technique for nth harmonics suppression. The proposed technique served by a microstrip electromagnetic bandgap cell is used to suppress the nth harmonics and reduce the length of a quarter-wave line over 30% as compared to the conventional divider. The planar structure enables an easy circuit design in printed circuit boards. From the measured results, a 32.5 dB suppression for the third harmonic and a 12 dB suppression for the fifth harmonic is obtained while maintaining the characteristics of a conventional Wilkinson power divider. It is able to achieve less than 3.4 0.1 dB of the two equivalent insertion losses, less than 23dB of the return loss, and better than 25dB of isolation at 2.4GHz. [ABSTRACT FROM PUBLISHER]

Colloidal quantum dot (CQD) solar cells have attracted great interest due to their low cost and superior photo-electric properties. Remarkable improvements in cell performances of both quantum dot sensitized solar cells (QDSCs) and PbX (X = S, Se) based CQD solar cells have been achieved in recent years, and the power conversion efficiencies (PCEs) exceeding 12% were reported so far. In this review, we will focus on the recent progress in CQD solar cells. We firstly summarize the advance of CQD sensitizer materials and the strategies for enhancing carrier collection efficiency in QDSCs, including developing multi-component alloyed CQDs and core-shell structured CQDs, as well as various methods to suppress interfacial carrier recombination. Then, we discuss the device architecture development of PbX CQD based solar cells and surface/interface passivation methods to increase light absorption and carrier extraction efficiencies. Finally, a short summary, challenge, and perspective are given. [ABSTRACT FROM AUTHOR]