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The interpretation of massive high-throughput gene expression data requires computational and biological analyses to identify statistically and biologically significant differences, respectively. There are abundant sources that describe computational tools for statistical analysis of massive gene expression data but few address data analysis for biological significance. In the present article we exemplify the importance of selecting the proper biological context in the human brain for gene expression data analysis and interpretation. For this purpose, we use cortical type as conceptual tool to make predictions about gene expression in areas of the human temporal cortex. We predict that the expression of genes related to glutamatergic transmission would be higher in areas of simpler cortical type, the expression of genes related to GABAergic transmission would be higher in areas of more complex cortical type, and the expression of genes related to epigenetic regulation would be higher in areas of simpler cortical type. Then, we test these predictions with gene expression data from several regions of the human temporal cortex obtained from the Allen Human Brain Atlas. We find that the expression of several genes shows statistically significant differences in agreement with the predicted gradual expression along the laminar complexity gradient of the human cortex, suggesting that simpler cortical types may have greater glutamatergic excitability and epigenetic turnover compared to more complex types; on the other hand, complex cortical types seem to have greater GABAergic inhibitory control compared to simpler types. Our results show that cortical type is a good predictor of synaptic plasticity, epigenetic turnover, and selective vulnerability in human cortical areas. Thus, cortical type can provide a meaningful context for interpreting high-throughput gene expression data in the human cerebral cortex.

This paper presents the vibration response of an elastic disc that is harmonically excited by a piezoelectric disc in an ultrasonic sensor structure. The ultrasonic sensor comprised an elastic disc combined with a cylindrical wall and attached to a small piezoelectric disc. The vibration response must be maximized by selecting the radius ratio and thickness ratio of the piezoelectric and elastic discs. Vibration distribution is necessary for analyzing the acoustic characteristics of ultrasound radiating from an ultrasonic sensor for distance measurement. The response equation for an elastic disc with a fixed boundary was theoretically obtained by considering the harmonic excitation of the piezoelectric disc. The vibration response distribution of the elastic disc coupled with a cylindrical wall was analyzed using finite elements to enhance the theoretical result. Experiments were performed to confirm the response distribution by exciting a piezoelectric disc in an enlarged specimen of an ultrasonic sensor structure. At the first natural frequency, the radius ratio of the maximum amplitude was 0.61, and the thickness ratio of the maximum amplitude approached zero. [ABSTRACT FROM AUTHOR]

• Cortical auditory evoked potentials distinguished a tinnitus and matched no-tinnitus control group with similar hearing, age, and sex. • The significantly larger ΔP2 amplitude in the tinnitus group represents increased excitation and reduced inhibition of sustained auditory stimulation. • Tinnitus best predicted ΔP2 amplitude, whereas the participant's age, hearing loss, temporal processing, and sex were not significant predictors. The current study investigates evidence of hypothesized reduced central inhibition and/or increased excitation in individuals with tinnitus by evaluating cortical auditory onset versus offset responses. Cortical auditory evoked potentials (CAEPs) were recorded to the onset and offset of 3-second white noise stimuli in tinnitus and control groups matched in pairs by age, hearing, and sex (n = 26 total). Independent t-tests and 2-way mixed model ANOVA were used to evaluate onset-offset differences in amplitude, area, and latency of CAEP components by group. The predictive influence of tinnitus presence and associated participant characteristics on CAEP outcomes was assessed by multiple regression proportional reduction in error. The tinnitus group had significantly larger onset minus offset P2 amplitudes (ΔP2 amplitudes) than control group participants. No other component variables differed significantly. ΔP2 amplitude was best predicted by tinnitus status and not significantly influenced by other variables such as hearing loss or age. Hypothesized reduced central inhibition and/or increased excitation in tinnitus participants was partially supported by a group difference in ΔP2 amplitude. This was the first study to evaluate CAEP onset minus offset differences to investigate changes in central excitation/inhibition in individuals with tinnitus versus controls in matched groups. [ABSTRACT FROM AUTHOR]

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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)

Porphyrin dimers have been widely explored and studied owing to their importance in photosynthetic systems. A vast variety of dimers linked by different groups and at different angles have been synthesized and studied; however, the means by which to synthesize rigidly fused porphyrins with direct conjugation of the chromophores remains limited. Such a class of porphyrins may possess interesting properties that unconjugated or stacked dimers may not exhibit. In this study, bisbenzimidazole‐fused porphyrin dimers and their mono‐ and bis−zinc derivatives are synthesized and characterized. As a consequence of excitonic coupling, these dimers exhibit a split Soret band irrespective of the metal ion in the porphyrin cavity. Steady‐state fluorescence and excitation spectra followed by femtosecond transient absorption spectral studies of the heterometallated dimer, (free‐base and zinc porphyrin) reveals the occurrence of efficient singlet‐singlet energy transfer (>95 % efficiency and rate constant >1012 s−1) within the dyad. Further, donor‐acceptor conjugates were formed by metal‐ligand axial coordination of phenyl imidazole functionalized C60 and were characterized by a variety of physicochemical techniques. Excited state charge separation from both singlet and triplet excited states of ZnP in the conjugates has been established. The lifetime of the final charge‐separated state was in the 30–40 μs range revealing charge stabilization. Interestingly, no charge separation in the conjugate derived from the heterometallated dimer was observed wherein excitation transfer dominated the process. The present study brings out the importance of the rigid π‐spacer connecting porphyrin dimers in governing the energy and electron transfer events when coupled with an electron acceptor. [ABSTRACT FROM AUTHOR]

The present study performed a DFT study on the conformation dependence of the properties of excited states and the excimer's formation for the tetramethyl tetraphenyl cyclotetrasiloxane. The conformations have little effect on the electronic structure of the ground state. The deformed phenyl group in the geometry of the excited state is the excimer‐forming site. The energetically matched HOMO of the excited state with the LUMO of the ground state should cause an attraction to form an excimer. Most conformations are likely to form the excimer but have different contributions to the excimer formation. The interaction of the ground state with the excited state in the excimer has been described quantitatively, which shows that the most stable intermolecular arrangement is the stacked‐eclipsed mode. The excimers display a broad excitation spectrum. The local excitation type is dominant during the excitation, and the charge transfer contributes to the excimer's stability. [ABSTRACT FROM AUTHOR]

Copyright of Electric Drive is the property of Electric Drive 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.)

The presubiculum (PRS) is an integral component of the perforant pathway that has recently been recognised as a relatively unscathed region in clinical Alzheimer's disease (AD), despite neighbouring components of the perforant pathway, CA1 and the entorhinal cortex, responsible for formation of episodic memory and storage, showing severe hallmarks of AD including, amyloid-beta (Aβ) plaques, tau tangles and marked gliosis. However, the question remains whether this anatomical resilience translates into functional resilience of the PRS neurons. Using neuroanatomy combined with whole-cell electrophysiological recordings, we investigated whether the unique spatial profile of the PRS was replicable in two knock-in mouse models of AD, APP NL-F/NL-F , and APP NL-F /MAPT HTAU and whether the intrinsic properties and morphological integrity of the PRS principal neurons was maintained compared to the lateral entorhinal cortex (LEC) and hippocampal CA1 principal cells. Our data revealed an age-dependent Aβ and tau pathology with neuroinflammation in the LEC and CA1, but a presence of fleece-like Aβ deposits with an absence of tau tangles and cellular markers of gliosis in the PRS of the mouse models at 11–16 and 18–22 months. These observations were consistent in human post-mortem AD tissue. This spatial profile also correlated with functional resilience of strong burst firing PRS pyramidal cells that showed unaltered sub- and suprathreshold intrinsic biophysical membrane properties and gross morphology in the AD models that were similar to the properties of pyramidal cells recorded in age-matched wild-type mice (11–14 months). This was in contrast to the LEC and CA1 principal cells which showed altered subthreshold intrinsic properties such as a higher input resistance, longer membrane time constants and hyperexcitability in response to suprathreshold stimulation that correlated with atrophied dendrites in both AD models. In conclusion, our data show for the first time that the unique anatomical profile of the PRS constitutes a diffuse AD pathology that is correlated with the preservation of principal pyramidal cell intrinsic biophysical and morphological properties despite alteration of LEC and CA1 pyramidal cells in two distinct genetic models of AD. Understanding the underlying mechanisms of this resilience could be beneficial in preventing the spread of disease pathology before cognitive deficits are precipitated in AD. [ABSTRACT FROM AUTHOR]

Understanding organic photovoltaic (OPV) work principles and the materials' optoelectronic properties is fundamental for developing novel heterojunction materials with the aim of improving power conversion efficiency (PCE) of organic solar cells. Here, in order to understand the PCE performance (>13%) of OPV device composed of the non-fullerene acceptor fusing naphtho[1,2-b:5,6-b′]dithiophene with two thieno[3,2-b]thiophene (IDCIC) and the polymer donor fluorobenzotriazole (FTAZ), with the aid of extensive quantum chemistry calculations, we investigated the geometries, molecular orbitals, excitations, electrostatic potentials, transferred charges and charge transfer distances of FTAZ, IDCIC and their complexes with face-on configurations, which was constructed as heterojunction interface model. The results indicate that, the prominent OPV performance of FTAZ:IDCIC heterojunction is caused by co-planarity between the donor and acceptor fragments in IDCIC, the the charge transfer (CT) and hybrid excitations of FTAZ and IDCIC, the complementary optical absorptions in visible region, and the large electrostatic potential difference between FTAZ and IDCIC. The electronic structures and excitations of FTAZ/IDCIC complexes suggest that exciton dissociation can fulfill through the decay of local excitation exciton in acceptor by means of hole transfer, which is quite different from the OPVs based on fullerenes acceptor. The rates of exciton dissociation, charge recombination and CT processes, which were evaluated by Marcus theory, support the efficient exciton dissociation that is also responsible for good photovoltaic performance. [ABSTRACT FROM AUTHOR]

Molecular stacking modes that determine morphology of bulk‐heterojunctions are important because of their effects on photovoltaic performance of organic solar cells (OSCs). Here, in order to investigate how molecular stacking pattern in OSCs heterojunction impact on electronic structures and properties, and then influence photovoltaic performance, this work selected D18:Y6 OSC as a representative system. On the basis of semi‐empirical quantum chemistry and density functional theory calculations, we studied the geometries, electronic structures and excitation properties, as well as electron and hole couplings of D18 and Y6 molecules, Y6 dimers, D18/Y6 and D18/Y6‐dimer complexes which are heterojunction interface models. The results indicate that the molecular stacking effects on open‐circuit voltage (VOC) can be attributed to the influences on charge transfer (CT) excitation energies because molecular stacking modes at donor/acceptor heterojunction interface can significantly change excitation energies. Furthermore, the molecular stacking modes can cause drastically different electron and hole couplings, and then affect charge transfer/transport rates. Hence, the molecular stacking effects on short‐circuit current density (JSC) can be understood from the effects on electron and hole couplings. The molecular stacking modes that are favorable to improving VOC and JSC of D18:Y6 OSC were also discussed. [ABSTRACT FROM AUTHOR]

This paper presents the common methods and corresponding drawbacks concerning nonlinear analysis of fluxgate excitation circuits and emphasizes the importance of nonlinear analysis for these circuits. With regard to the nonlinearity of the excitation circuit, this paper proposes the use of the core-measured hysteresis curve for mathematical analysis and the use of a nonlinear model that considers the coupling effect of the core and winding and influence of the historical magnetic field on the core for simulation analysis. The feasibility of mathematical calculations and simulation for the nonlinear study of fluxgate excitation circuit is verified via experiments. The results demonstrate that, in this regard, the simulation is four times better than a mathematical calculation. The simulation and experimental results of the excitation current and voltage waveforms under different excitation circuit parameters and structures are essentially consistent, with a difference in current of no more than 1 mA, thereby verifying the effectiveness of the nonlinear excitation analysis method. [ABSTRACT FROM AUTHOR]

Our study has shown that in collisions p-He and p-Ar with energies above 50 keV fast electrons carry away as kinetic energy up to 70 % of energy released during particle stopping. Ignoring the fast electron contribution makes impossible bringing independently measured cross sections of elementary processes of ionization, excitation, stripping and charge exchange into compliance with measured cross sections of electronic stopping. Fast electron emission in collisions of energetic ions with solids may induce extra radiation effects (create additional vacancies and defects in solid). Mean kinetic energies of ejected electrons W e obtained from the analysis of cross section ratio agree well with directly measured energy spectra of the emitted electrons. The dynamic ionization theory implies the W e proportionality to initial velocity v. In the considered cases, such a dependence takes place at the velocities below 2 a.u. At higher velocities, the observed dependence is successfully described in the framework of the Born approximation. [ABSTRACT FROM AUTHOR]

Sloshing in fuel tanks is one of the major sources of noise in hybrid and high-end vehicles. During sloshing, the fluid causes impacts on tank walls resulting in their vibration, which further leads to noise, referred to as "hit noise." Therefore, hit noise generation is a multi-physics phenomenon involving fluid flow, structural response, and acoustic radiation. This paper presents a multi-physics approach to predict hit noise in a rectangular tank. The methodology involves the prediction of fluid loading on tank walls and their structural response using transient fluid and structural analyses which are weakly coupled. Radiated hit noise is predicted using acoustic finite element analysis. Longitudinal periodic excitation is applied to the fluid domain at different frequencies to simulate the sloshing regime which has dominant fluid-structure interactions. Parameters like tank wall pressures, the resulting dynamic acceleration, and radiated sound pressure levels are monitored and validated with the experimental results available in the literature. [ABSTRACT FROM AUTHOR]

Rare earth doped compositions Na 3-3 x Ln x Fe 2 (PO 4) 3 (x = 0, 0.025, 0.05, 0.075 and 0.1) were prepared by ion-exchange method using Na 3 Fe 2 (PO 4) 3 and LnCl 3 (Ln = Eu and Tb). Pristine Na 3 Fe 2 (PO 4) 3 was obtained by ethylene glycol assisted gel burning procedure. The phase characterization was performed by powder X-ray diffraction (XRD). All the compositions were well crystalized in monoclinic lattice. The FE-SEM images and elemental mapping were obtained. The infrared and Raman profiles of all-compounds were dominated by the bands owing to the (PO 4) units. Investigation on photoluminescence emission and excitation spectra of Ln3+ (Ln = Eu, Tb) were carried out. The excitation spectra of Na 3-3 x Ln x Fe 2 (PO 4) 3 (Ln = Eu and Tb) gave intensive band at 256 (370) nm for Eu (Tb) doped phosphors. The photoluminescence emission spectra of Ln3+ (Ln = Eu, Tb) were carried out. The emission spectra of these composition were characterized by f -f transitions corresponding to 613 (5D 0 →7F 2) for Eu and 543 (5D 4 →7F 5) for Tb doped compositions. The maximum emission intensity for Eu (Tb) doped phosphors was found at x = 0.075 (0.05). The analysis of CIE and CCT values of all prepared phosphors were also carried out. Decay curves were analyzed in detail. The visible-light photo-catalytic activity of parent Na 3 Fe 2 (PO 4) 3 was examined against decomposition of methylene blue and methyl orange dyes. Parent Na 3 Fe 2 (PO 4) 3 exhibits good efficiency against MB (≈94.5 %) and moderate efficiency against MO (≈64 %) in 180 min of visible light irradiation. Scavengers' experiments were carried to identify the active species during photodegradation. Na 3 Fe 2 (PO 4) 3 : Eu/Tb doped Na 3 Fe 2 (PO 4) 3 ; Photocatalytic and luminescence investigation. [Display omitted] • Gel burning method was used to obtain Na 3 Fe 2 (PO 4) 3 , while Ln3+ doped compositions were prepared using ion-exchange method. • The PLE, emission, CIE colour coordinates, colour purity, life times and CCT values are deduced for Eu3+ and Tb3+-doped NFPO. • The photocatalytic activity of NFPO was studied against the degradation of methylene-blue (MB) and methyl orange (MO) dyes. [ABSTRACT FROM AUTHOR]

The impeller in vortex pumps is installed at the side of the volute, which causes the flow instability and vibration. This study employs the Renormalization Group k-epsilon (RNG k-ε) turbulence model to investigate the unsteady flow and excitation characteristics within a vortex pump under various flow rates. The results show that increasing the flow rate reduces the low-pressure area in the vaneless chamber, with flow instability primarily occurring in the middle of the vaneless chamber and intensifying with higher flow rate. Pressure pulsation within the vaneless chamber at nominal flow rate is driven by periodic changes in the vortex structure, occurring at approximately twice the shaft frequency (96Hz). As the impeller rotates, pulsation energy propagates from the vaneless chamber to the tongue and outlet. With increasing flow rates, variations of inlet axial flow velocity cause the rise in pressure pulsation in the vaneless chamber. At high flow rate, pressure pulsation in the vaneless chamber increases tenfold compared to low flow rate. The pressure pulsation at the tongue is significantly smaller than that in the vaneless chamber. The rise in pressure pulsation with increasing flow rates is attributed to the displacement of the circulation flow position towards the tongue. • Time-averaged method was used to analyze the flow field of a vortex pump. • Vortex structure change in the vaneless chamber was the main cause of excitation, about twice the shaft frequency. • Increased flow rate raised inlet axial flow velocity, leading to higher pressure pulsation in the vaneless chamber. • Pressure pulsation rose as the circulation flow moved toward the tongue with increasing flow rate. [ABSTRACT FROM AUTHOR]

Distinct genetic forms of autism are hypothesized to share a common increase in excitation-inhibition (E-I) ratio in cerebral cortex, causing hyperexcitability and excess spiking. We provide a systematic test of this hypothesis across 4 mouse models (Fmr1-/y, Cntnap2-/-, 16p11.2del/+, Tsc2+/-), focusing on somatosensory cortex. All autism mutants showed reduced feedforward inhibition in layer 2/3 coupled with more modest, variable reduction in feedforward excitation, driving a common increase in E-I conductance ratio. Despite this, feedforward spiking, synaptic depolarization, and spontaneous spiking were largely normal. Modeling revealed that E and I conductance changes in each mutant were quantitatively matched to yield stable, not increased, synaptic depolarization for cells near spike threshold. Correspondingly, whisker-evoked spiking was not increased in vivo despite detectably reduced inhibition. Thus, elevated E-I ratio is a common circuit phenotype but appears to reflect homeostatic stabilization of synaptic drive rather than driving network hyperexcitability in autism.

Directional responses in retinal ganglion cells are generated in large part by direction-selective release of γ-aminobutyric acid from starburst amacrine cells onto direction-selective ganglion cells (DSGCs). The excitatory inputs to DSGCs are also widely reported to be direction-selective, however, recent evidence suggests that glutamate release from bipolar cells is not directional, and directional excitation seen in patch-clamp analyses may be an artifact resulting from incomplete voltage control. Here, we test this voltage-clamp-artifact hypothesis in recordings from 62 ON-OFF DSGCs in the rabbit retina. The strength of the directional excitatory signal varies considerably across the sample of cells, but is not correlated with the strength of directional inhibition, as required for a voltage-clamp artifact. These results implicate additional mechanisms in generating directional excitatory inputs to DSGCs.

The impact of D,L – homocysteic acid (DLH) microinjection (non-specific glutamate receptor agonist that causes excitation of neurons) into the Bötzinger complex area (BOT) was simulated using computer model of quiet breathing and cough reflex. Integrated signals from simulated neuronal populations innervating inspiratory phrenic and expiratory lumbar motoneurons were obtained. We analysed durations and amplitudes of these “pre-phrenic and pre-lumbar” activities during quiet breathing and cough reflex and the number of coughs elicited by a fictive 10-second-long stimulation. Model fibre population provides virtual DLH related excitation to expiratory neuronal populations with augmenting discharge pattern (BOT neurons). The excitation was modelled by a higher number of fibres and terminals (simulated a higher number of excitatory inputs) or by a higher synaptic strength (simulated a higher effect of excitatory inputs).

To improve the numerical efficiency of the nonlinear calculations required for the dynamic response of damped turbine blades, the authors recently introduced the platform centered reduction (PCR) method which represents the platform as a rigid body subject to a single moment representing the effect of forces from adjacent dampers. The concept of a" basic cycle" is now introduced to simplify--without introducing additional approximations--the functional relationship between the moment on the platform due to the frictional forces and its angle of rotation, both of which are calculated around an axis parallel to the main axis of neck bending. It is shown that, for the first bending mode of vibration, this function completely characterizes the damper-platform assembly, such that for rotation values greater than the" base cycle," the values of the real and imaginary components of the damper-platform flexural stiffness are obtained a priori, without having to repeat the contact cycle calculations at each amplitude change. The advantage of this approach for numerical calculations and the convenience of having a model focused on the essential aspects of the engineering problem of best coupling between damper and blade are demonstrated. Also, considering the improvements introduced, the" designer's diagram," already proposed by these authors, is revised. The advantage lies in representing the essential, yet adequate approximation in the relationship between the maximum alternating bending stress due to vibration and the values of the excitation force on the airfoil, values each associated with a corresponding "oscillation amplitude/resonance frequency" pair. [ABSTRACT FROM AUTHOR]

To enable an accurate recognition of neuronal excitability in an epileptic brain for modeling or localization of epileptic zone, here the brain response to single-pulse electrical stimulation (SPES) has been decomposed into its constituent components using adaptive singular spectrum analysis (SSA). Given the response at neuronal level, these components are expected to be the inhibitory and excitatory components. The prime objective is to thoroughly investigate the nature of delayed responses (elicited between 100 ms–1 s after SPES) for localization of the epileptic zone. SSA is a powerful subspace signal analysis method for separation of single channel signals into their constituent uncorrelated components. The consistency in the results for both early and delayed brain responses verifies the usability of the approach. [ABSTRACT FROM AUTHOR]

We investigate the effect of transverse acoustic excitation on nonreacting swirling jets. The work is motivated by the azimuthal instabilities in annular gas turbine combustor which are one of the major challenges in aero-engines. We have designed and fabricated a multinozzle linear array combustor to simulate the flow conditions of an annular combustor. The nozzle features a dual corotating radial swirler configuration. Two compression drivers placed on either side of the combustion chamber are used to generate acoustic fields in the direction transverse to the flow. Simultaneous two-dimensional (2D) particle image velocimetry (PIV) and high-frequency pressure measurements are conducted to measure the time-averaged velocity field and the chamber acoustics, respectively. It is observed that once the swirling jet is excited with a transverse acoustic forcing, it instantaneously transitions to a wall-jet state. In wall-jet state, the flow moves radially outwards and remains attached to the walls on either side of the nozzle, and is characterized by a recirculation zone with a strong negative axial velocity. In our experiments, we demonstrate that transverse acoustic excitation can lead to a bistable state in swirling flows. We investigated the acoustic response to low-amplitude forcing on the combustion chamber by performing a forced acoustic response analysis using comsol. It is observed that acoustic forcing leads to a peak response of the radial and azimuthal velocities at the flare of the swirler, which could induce an axisymmetric deflection of the jet shear layer pushing it into a wall-jet state. [ABSTRACT FROM AUTHOR]

Modern turbomachinery favors pocket damper seals (PDS) which produce more effective damping than labyrinth seals (LS). Liquid tolerant compressors enable deep sea oil and gas (O&G) facilities; and seals supplied with a two-phase flow can have an impact on the stability and leakage of O&G turbomachinery. This paper details results for the leakage and force coefficients of a stepped shaft PDS and LS. The seals operate with speeds up to 5250 rpm and pressure ratios (inlet/exit) = 2.5-4.2. The seals are supplied with an oil-in-air mixture with liquid volume fraction (LVF) up to 10%. Both seals feature the same shaft diameter D = 127 mm, axial length L = 0.38D, four blades (and eight pockets). The LS has a 15% larger clearance than the PDS. Operating with pure gas, the PDS is 25% more effective to restrict leakage than the LS. The effective clearance of the PDS decreases as LVF increases whereas that for the LS increases. The direct stiffness (K) for both seals is small and becomes negative as LVF increases. The PDS produces greater direct damping (C) when operating with an identical LVF. The PDS C grows as the LVF increases. Predictions of leakage agree with measurements, whereas force coefficients are roughly half of the experimental results. Changes in LVF produced subsynchronous vibrations (SSV) in the PDS, but not so in the LS. The results are a reference for the design of seals operating with two-phase flow. [ABSTRACT FROM AUTHOR]

Conscious experience represents one of the most elusive problems of empirical science, namely neuroscience. The main objective of empirical studies of consciousness has been to describe the minimal sets of neural events necessary for a specific neuronal state to become consciously experienced. The current state of the art still does not meet this objective but rather consists of highly speculative theories based on correlates of consciousness and an ever-growing list of knowledge gaps. The current state of the art is defined by the limitations of past stimulation techniques and the emphasis on the observational approach. However, looking at the current stimulation technologies that are becoming more accurate, it is time to consider an alternative approach to studying consciousness, which builds on the methodology of causal explanations via causal alterations. The aim of this methodology is to move beyond the correlates of consciousness and focus directly on the mechanisms of consciousness with the help of the currently focused brain stimulation techniques, such as geodesic transcranial electric neuromodulation. This approach not only overcomes the limitations of the correlational methodology but will also become another firm step in the following science of consciousness. [ABSTRACT FROM AUTHOR]

Copyright of Contemporary Islamic Studiens Magazine is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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 interaction between a proton and a ground state hydrogen atom is studied using a standard three-body classical trajectory Monte Carlo (CTMC) and a quasi-classical trajectory Monte Carlo (QCTMC) model where the quantum feature of the collision system is mimicked using the model potential in the Hamiltonian as was proposed by Kirschbaum and Wilets (1980 Phys. Rev. A 21 834). The influence of the choice of the model potential parameters (α, Îľ) on the initial radial and momentum distribution of the electron are analyzed and optimized. We found that although these distributions may not be as close to the quantum results as the distribution of standard CTMC results, we can find the combination of the (α, Îľ) where the calculated cross sections are closer to the experimental data and closer to the results obtained quantum mechanically. We show that the choice of 3 < α < 5 is reasonable. To validate our observation, we present cross sections for ionization, excitation, charge exchange (CX), and state selective CX to the projectile bound state. Calculations are carried out in the projectile energy range between 10 and 1000 keV amuâˆ'1. [ABSTRACT FROM AUTHOR]

In this study, the effects of multi-excitation on the vibration responses of each planetary gear component is investigated based on the translational-rotational dynamic model of planetary gear system. The Fourier series are introduced to simulate the excitation sources, and the frequency–response function are applied to determine the effects of excitation sources on the vibration responses of each planetary gear component in the whole frequency. Therefore, the superposition problem of multi-component vibration responses is effectively solved under multi-excitation sources. Based on the analysis approach, the effects on the vibration response of the sun, carrier, ring, and planet gears are evaluated and compared in detail for planet-ring mesh, sun-planet mesh, floating sun gear, motor torque fluctuation, variable load, gearbox translational vibration, and gearbox rotational vibration. From these results, the mapping is revealed about relationship between excitation sources and the vibration response of each planetary gear component. Combined with the mapping relations, the main vibration component of planetary gear system can be predicted. [ABSTRACT FROM AUTHOR]

Biomolecular NMR spectroscopy requires large magnetic field strengths for high spectral resolution. Today's highest fields comprise proton Larmor frequencies of 1.2 GHz and even larger field strengths are to be expected in the future. In protein triple resonance experiments, various carbon bandwidths need to be excited by selective pulses including the large aliphatic chemical shift range. When the spectrometer field strength is increased, the length of these pulses has to be decreased by the same factor, resulting in higher rf-amplitudes being necessary in order to cover the required frequency region. Currently available band-selective pulses like Q3/Q5 excite a narrow bandwidth compared to the necessary rf-amplitude. Because the maximum rf-power allowed in probeheads is limited, none of the selective universal rotation pulses reported so far is able to cover the full 13 C aliphatic region on 1.2 GHz spectrometers. In this work, we present band-selective 90° and 180° universal rotation pulses (SURBOP90 and SURBOP180) that have a higher ratio of selective bandwidth to maximum rf-amplitude than standard pulses. Simulations show that these pulses perform better than standard pulses, e. g. Q3/Q5, especially when rf-inhomogeneity is taken into account. The theoretical and experimental performance is demonstrated in offset profiles and by implementing the SURBOP pulses in an HNCACB experiment at 1.2 GHz. [ABSTRACT FROM AUTHOR]

While healthy brain function relies on a dynamic but tightly regulated interaction between excitation (E) and inhibition (I), a spectrum of social cognition disorders, including antisocial behavior and antisocial personality disorder (ASPD), frequently ensuing from irregular neurodevelopment, may be associated with E/I imbalance and concomitant alterations in neural connectivity. Technological advances in the evaluation of structural and functional E/I balance proxies in clinical settings and in human cell culture models provide a general basis for identification of biomarkers providing a powerful concept for prevention and intervention across different dimensions of mental health and disease. In this perspective we outline a framework for research to characterize neurodevelopmental pathways to antisocial behavior and ASPD driven by (epi)genetic factors across life, and to identify molecular targets for preventing the detrimental effects of cognitive dysfunction and maladaptive social behavior, considering psychosocial experience; to validate signatures of E/I imbalance and altered myelination proxies as biomarkers of pathogenic neural circuitry mechanisms to determine etiological processes in the transition from mental health to antisocial behavior and ASPD and in the switch from prevention to treatment; to develop a neurobiologically-grounded integrative model of antisocial behavior and ASPD resultant of disrupted E/I balance, allowing to establish objective diagnoses and monitoring tools, to personalize prevention and therapeutic decisions, to predict treatment response, and thus counteract relapse; and finally, to promote transformation of dimensional disorder taxonomy and to enhance societal awareness and reception of the neurobiological basis of antisocial behavior and ASPD., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier Ltd.)

Contraction and relaxation within the heart is controlled by the coordinated rise and fall of Ca 2+ levels within the cytosol of cardiomyocytes. This requires Ca 2+ to be moved between subcellular and extracellular compartments with each cardiac cycle, since Ca 2+ is not destroyed or broken down by the excitation-contraction and relaxation cycles. Many cardiac pathologies alter Ca 2+ homeostasis and can lead to impaired contraction, incomplete relaxation, and arrhythmias. Ca 2+ -sensitive fluorescent probes enable monitoring of Ca 2+ cycling and can be used to detect pathological changes that can then be investigated using novel therapeutic strategies in isolated heart cells and tissues. This chapter will describe simultaneous measurements of intracellular Ca 2+ using the ratiometric indicator fura-2/AM, and contractile force in isolated multicellular muscles (trabeculae) dissected from rat hearts, or from viable samples of human right atrial appendage., (© 2025. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Determining the severity level of hypoxemia, the scarcity of saturated oxygen (SpO2) in the human body, is very important for the patients, a matter which has become even more significant during the outbreak of Covid-19 variants. Although the widespread usage of Pulse Oximeter has helped the doctors aware of the current level of SpO2 and thereby determine the hypoxemia severity of a particular patient, the high sensitivity of the device can lead to the desensitization of the care-givers, resulting in slower response to actual hypoxemia event. There has been research conducted for the detection of severity level using various parameters and bio-signals and feeding them in a machine learning algorithm. However, in this paper, we have proposed a new residual-squeeze-excitation-attention based convolutional network (Res-SE-ConvNet) using only Photoplethysmography (PPG) signal for the comfortability of the patient. Unlike the other methods, the proposed method has outperformed the standard state-of-art methods as the result shows 96.5% accuracy in determining 3 class severity problems with 0.79 Cohen Kappa score. This method has the potential to aid the patients in receiving the benefit of an automatic and faster clinical decision support system, thus handling the severity of hypoxemia.

The excitation system of the hydro unit is a static self-excitation system that uses thyristor rectifiers in a three-phase fully controllable bridge connection with a digital two-channel regulation system characterized by a very fast response (eng. high initial response ratio). The excitation system is powered by an excitation transformer connected to the busbars of the aggregate with a transmission ratio of 14.4/0.42 kV. The aim of this project is to show the characteristics of the old ABB UNITROL 5000 excitation system as well as the improvements obtained by installing the new ABB UNITROL 6000 excitation system of unit 1 at the Trebinje Hydroelectric Power Plant 1. The reconstruction of the excitation system was carried out as part of the regular annual overhaul of the hydroelectric power plant by representatives of the company "Advensys engineering" d.o.o. - Zagreb, through cooperation with the staff of the power plant. The basic scope of the system reconstruction consists of three units and includes the replacement of the control part of the excitation, the replacement of the excitation switch and the replacement of the excitation control panel.

In this work, a krypton gas impurity seeding experiment was conducted in a Large Helical Device. Emission lines from the Na-like Kr ion in the extreme ultraviolet wavelength region, such as 22.00 nm, 17.89 nm, 16.51 nm, 15.99 nm, and 14.08 nm, respective to 2p63p(2P1/2o)−2p63s(2S1/2), 2p63p(2P3/2o)−2p63s(2S1/2), 2p63d(2D3/2)−2p63p(2P3/2o), 2p63d(2D5/2)−2p63p(2P3/2o), and 2p63d(2D3/2)−2p63p(2P1/2o) transitions, are observed. In order to generate a theoretical synthetic spectrum, an extensive calculation concerning the excitation of the Kr25+ ion through electron impact was performed for the development of a suitable plasma model. For this, the relativistic multiconfiguration Dirac–Hartree–Fock method was employed along with its extension to the relativistic configuration interaction method to compute the relativistic bound-state wave functions and excitation energies of the fine structure levels using the General Relativistic Atomic Structure Package-2018. In addition, another set of calculations was carried out utilizing the relativistic many-body perturbation theory and relativistic configuration interaction methods integrated within the Flexible Atomic Code. To investigate the reliability of our findings, the results of excitation energies, transition probabilities, and weighted oscillator strengths of different dipole-allowed transitions obtained from these different methods are presented and compared with the available data. Further, the detailed electron impact excitation cross-sections and their respective rate coefficients are obtained for various fine structure resolved transitions using the fully relativistic distorted wave method. Rate coefficients, calculated using the Flexible Atomic Code for population and de-population kinetic processes, are integrated into the collisional-radiative plasma model to generate a theoretical spectrum. Further, the emission lines observed from the Kr25+ ion in the impurity seeding experiment were compared with the present plasma model spectrum, demonstrating a noteworthy overall agreement between the measurement and the theoretical synthetic spectrum.

Developmental changes in ionic balance are associated with crucial hallmarks in neural circuit formation, including changes in excitation and inhibition, neurogenesis, and synaptogenesis. Neuronal excitability is largely mediated by ionic concentrations inside and outside of the cell, and chloride (Cl-) ions are highly influential in early neurodevelopmental events. For example, g-aminobutyric acid (GABA) is the main inhibitory neurotransmitter of the mature central nervous system (CNS). However, during early development GABA can depolarize target neurons, and GABAergic depolarization is implicated in crucial neurodevelopmental processes. This developmental shift of GABAergic neurotransmission from depolarizing to hyperpolarizing output is induced by changes in Cl- gradients, which are generated by the relative expression of Cl- transporters Nkcc1 and Kcc2. Interestingly, the GABA polarity shift is delayed in Fragile X syndrome (FXS) models; FXS is one of the most common heritable neurodevelopmental disorders. The RNA binding protein FMRP, encoded by the gene Fragile X Messenger Ribonucleoprotein-1 (Fmr1) and absent in FXS, appears to regulate chloride transporter expression. This could dramatically influence FXS phenotypes, as the syndrome is hypothesized to be rooted in defects in neural circuit development and imbalanced excitatory/inhibitory (E/I) neurotransmission. In this perspective, we summarize canonical Cl- transporter expression and investigate altered gene and protein expression of Nkcc1 and Kcc2 in FXS models. We then discuss interactions between Cl- transporters and neurotransmission complexes, and how these links could cause imbalances in inhibitory neurotransmission that may alter mature circuits. Finally, we highlight current therapeutic strategies and promising new directions in targeting Cl- transporter expression in FXS patients. [ABSTRACT FROM AUTHOR]

The brain’s connectome provides the scaffold for canonical neural computations. However, a comparison of connectivity studies in the mouse primary visual cortex (V1) reveals that the average number and strength of connections between specific neuron types can vary. Can variability in V1 connectivity measurements coexist with canonical neural computations? We developed a theory-driven approach to deduce V1 network connectivity from visual responses in mouse V1 and visual thalamus (dLGN). Our method revealed that the same recorded visual responses were captured by multiple connectivity configurations. Remarkably, the magnitude and selectivity of connectivity weights followed a specific order acrossmost of the inferred connectivity configurations. We argue that this order stems fromthe specific shapes of the recorded contrast response functions and contrast invariance of orientation tuning. Remarkably, despite variability across connectivity studies, connectivity weights computed from individual published connectivity reports followed the order we identified with our method, suggesting that the relations between the weights, rather than theirmagnitudes, represent a connectivity motif supporting canonical V1 computations. [ABSTRACT FROM AUTHOR]

The paper presents the results of the studies into the photoluminescence of cytosine molecules in a neutral liquid medium induced by the radiation of a xenon lamp with a wavelength of 280 nm. It was found that the luminescence is represented by a wide band with a vague threshold at a wavelength of 340 nm and a blurred maximum in the spectral region of 365-380 nm. It is shown that the presented luminescence curve reflects fluorescence, while phosphorescence is absent entirely. The lack of phosphorescence can be explained by the effect of the solvent. The obtained results are compared with the data of known studies. The discrepancies found may be primarily due to the pH of the solvents used in the previous studies. It is the first time that experiments with the excitation of luminescence of a neutral liquid solution of cytosine molecules under the simultaneous action of xenon lamp radiation with a wavelength of 280 nm and a continuous laser beam with a wavelength of 530 nm and a power of 0.25 W have been performed. It has been established that under these experimental conditions the luminescence curve acquires a qualitatively new form - the luminescence threshold is shifted to the short-wavelength region, and the luminescence curve has an additional maximum at a wavelength of 410 nm. An explanation of the physical nature of this phenomenon is given, which is that the intense electromagnetic field generated by the laser promotes the efficient formation of singlet exciters of cytosine (photodimers). In the process of their decay, cytosine photodimers form excited monomers in singlet states which, by intercombinational conversion (intersystem crossing), intensively populate metastable triplet states. The radiation decay of the formed metastable triplet states causes phosphorescence, which is the reason for the appearance of the second maximum in the wavelength range of 410 nm. Attention is drawn to the fact that metastable triplet states play a key role in the photochemistry of nucleic acid bases and presumably will have a major impact on the development of new biotechnologies. [ABSTRACT FROM AUTHOR]

In the development of most phenomenological models used to explain the infrared excited luminescence, a major assumption is usually made in the degree of freedom the excited charge has. One of the two extremes is normally assumed: charge is free to move anywhere over the whole crystal, or it is confined close to the trap and the centers immediately adjacent to it. Determining which of these extremes is more reasonable is difficult to do on the basis of the temporal behavior of the luminescence intensity alone. However, this assumption has important consequences for the understanding of the dynamics of the luminescence process because of the difference in the number of recombination and trapping centers available to the excited charge. Additional experimental evidence was thus sought on this aspect of charge movement. One such experiment is the detection of photoconductivity in which an electrical current is measured during optical excitation or shortly there-after. In this paper, the details of photoconductivity experiments on K crystal are presented. Photoconductivity measurements were inconclusive as to whether or not there was a current flowing during the 850 nm excitation of a feldspar sample. However, there was a clear current when exciting the same sample with 515 nm light, but there was a complex relationship between the magnitude of the current and the number of emission photons counted. A model was developed to explain the photoconductivity results where electrons migrate through the conduction band aided by thermal excitation and tunneling. [ABSTRACT FROM AUTHOR]

Lanthanide ion (Ln3+) doped Y2O3 materials are used in making display devices. Ln3+ ions can occupy C2 and S6 sites in Y2O3. In many reported papers, Ln3+ ions occupy more C2 site leading to enhanced luminescence intensity of electric dipole transition as compared to that of magnetic dipole transition. In this study, we have prepared Eu3+ ion doped Y2O3 particles dispersed in silica (SiO2) using urea hydrolysis at 165°C. Among the prepared samples lower heated sample show cubic phase Y2O3 wherease 1400oC show α-Y2Si2O7 and all the samples show the luminescence characteristics of Eu3+. In Y2O3:Eu-SiO2, the as-prepared, 500 and 900°C heated samples show the higher luminescence intensity for the electric dipole transition than that of magnetic dipole transition and it is opposite upon annealed at 1400°C. It confirms that Eu3+ ions in as-prepared, 500 and 900°C heated samples occupy C2 site (asymmetric environment), whereas in 1400°C heated sample, they occupy the S6 site (symmetric environment). However, microparticles of the Y2O3:Eu sample annealed at 1400°C show that Eu3+ ions occupy more C2 site as compared to the S6 site. This study suggests that occupancy of C2 and S6 sites in Y2O3 by Eu3+ ions can be varied by surrounding medium as well as heat-treatment temperature. [ABSTRACT FROM AUTHOR]

Transient coupling between the traces in a double-layer printed circuit board (PCB) is analysed for excitation with different signal waveforms involved in the digital circuits. Different types of signals such as trapezoidal, step, impulse and clock are considered for excitation at the source end in a two-layer board having three traces on the top of the substrate. All the traces are matched terminated with 50-ohm loads. The source waveforms are represented by mathematical formulae and the transient crosstalk is computed using transmission line theory. The capacitive and inductive coupling elements are calculated using the Method of Moments (MoM). Initially, the transient crosstalk is calculated on the adjacent victim traces for excitation in a single trace. Subsequently, two different input signals are applied simultaneously to the two side traces and the effect of transient coupling is determined on the middle trace. The computation of the results is done by using MATLAB. The variation of coupling is also studied for different PCB configurations such as spacing between the traces, substrate height and dielectric constant, and terminating loads. The results are compared graphically. It is observed that the transient coupling increases with a decrease in the rise time of the pulses. [ABSTRACT FROM AUTHOR]

The response of the solid fuel ramjet to the imposed excitations of the ambient pressure is investigated using full part computation of the system including the intake, combustion chamber, and exhaust nozzle. The finite volume solver of the turbulent reacting compressible flow is used to simulate the flow field, where two grid blocks are considered for discretizing the computational domain. Both impulsive and oscillatory excitations are imposed to predict the response of the solid fuel mass flow rate. The results demonstrate that strong fuel flow overshoot occurs in the case of sudden impulsive excitation which is omitted for gradual impulsive excitations. In addition, the oscillatory excitations eventually lead to regular oscillatory response with frequencies similar to the imposed excitations and decrease the average fuel mass flow rate independent of the excitation frequency. But the amplitude of the response depends on the excitation frequency and amplification occurs in some frequencies. This behavior is not related to the combustion instabilities and is similar to the L-star instability in the solid rocket motors. In the design and analysis of the solid fuel ramjets, the coupling of the flight dynamics and the engine performance must be considered, and this study is the first step of such complete methodology to have more accurate predictions. [ABSTRACT FROM AUTHOR]

In order to study the influence of random manufacturing error on the vibration characteristics of differential gear drive system of a new energy vehicle，the Lagrange energy method is used to establish the bending torsion shaft coupling vibration dynamic model of differential gear drive under multi-source time-varying excitation. The base pitch error and tooth profile error of the gear system are regarded as random variables，which are described by the random variables following the normal distribution law，and the dynamics analysis of the differential reducer transmission system is carried out by using the numerical simulation software. The results show that with the increase of random manufacturing error dispersion，the axial vibration amplitude of gear pair increases gradually，but the radial vibration of gear pair has no obvious change.