Auditory processing in patients with temporal lobe epilepsy: A systematic review and meta-analysis.

BACKGROUND: Hearing efficiency is known to influence and interact with communication and mental health. Hearing impairment may be hidden when co-occurring with neurological disorders. PURPOSE: We performed a systematic review and meta-analysis in order to address the following questions: 1) which specific tools of auditory processing show clear deficits, separating Temporal Lobe Epilepsy (TLE) patients from normal controls,2) How well is TLE evaluated in terms of hearing and auditory processing? METHODS: The study inclusion criteria were: 1) patients diagnosed with temporal lobe epilepsy, 2) presence of a normal control group, 3) auditory processing assessment using auditory stimuli with behavioral tests and/or P300 or Mitch Match Negativity (MMN) latency and/or amplitude, 4) publications written in English, 5) publication date after 2000. 132 articles were retrieved and based on PRISMA & PICO criteria 23 articles were analyzed. RESULTS: Temporal resolution and processing as measured by the behavioral tests of Gaps-In-Noise (GIN) and Duration Pattern Test (DPT) document deficiencies in TLE patients and separate them from normal controls. Electrophysiology as measured by MMN & P300 shows statistically significant differences in TLE patients compared to controls with patients showing deficient auditory processing. A clear difference between studies with psychoacoustic assessment as opposed to electrophysiology ones may be due to lacking or incomplete evaluation of peripheral hearing by gold standard tools (76.9% in electrophysiology studies). CONCLUSION: Auditory processing is deficient in patients with TLE. There is a clear need to evaluate hearing efficiency before proceeding to auditory processing evaluation with behavioral or electrophysiological tests.

Investigation of the Mechanism of Membrane Potential Generation by Heme-Copper Respiratory Oxidases in a Real Time Mode.

Heme-copper respiratory oxidases are highly efficient molecular machines. These membrane enzymes catalyze the final step of cellular respiration in eukaryotes and many prokaryotes: the transfer of electrons from cytochromes or quinols to molecular oxygen and oxygen reduction to water. The free energy released in this redox reaction is converted by heme-copper respiratory oxidases into the transmembrane gradient of the electrochemical potential of hydrogen ions H+). Heme-copper respiratory oxidases have a unique mechanism for generating H+, namely, a redox-coupled proton pump. A combination of direct electrometric method for measuring the kinetics of membrane potential generation with the methods of prestationary kinetics and site-directed mutagenesis in the studies of heme-copper oxidases allows to obtain a unique information on the translocation of protons inside the proteins in real time. The review summarizes the data of studies employing time-resolved electrometry to decipher the mechanisms of functioning of these important bioenergetic enzymes.

A Comprehensive Characterization of the TI-LGAD Technology.

Pixelated low-gain avalanche diodes (LGADs) can provide both precision spatial and temporal measurements for charged particle detection; however, electrical termination between the pixels yields a no-gain region, such that the active area or fill factor is not sufficient for small pixel sizes. Trench-isolated LGADs (TI-LGADs) are a strong candidate for solving the fill-factor problem, as the p-stop termination structure is replaced by isolated trenches etched in the silicon itself. In the TI-LGAD process, the p-stop termination structure, typical of LGADs, is replaced by isolating trenches etched in the silicon itself. This modification substantially reduces the size of the no-gain region, thus enabling the implementation of small pixels with an adequate fill factor value. In this article, a systematic characterization of the TI-RD50 production, the first of its kind entirely dedicated to the TI-LGAD technology, is presented. Designs are ranked according to their measured inter-pixel distance, and the time resolution is compared against the regular LGAD technology.

Description of a Dimethylmercury Automatic Analyzer for the High-Resolution Measurement of Dissolved Gaseous Mercury Species in Surface Ocean Waters.

Our understanding of the significance of dimethylmercury (DMHg) to the mercury (Hg) global ocean biogeochemical cycle is unclear because of the lack of detailed DMHg measurements in the water column. To our knowledge, 30 years of published studies have generated no more than 200 DMHg data points in the ocean surface waters and marine boundary layer (MBL). To improve the precision and reduce the uncertainty in determining DMHg in surface seawater, we developed a simple and robust DMHg automatic analyzer (DAA). This DAA system couples the main sampling and analytic steps, including a continuous flow chamber, with dual Carbotrap preconcentration, a gas chromatographic column, a cold vapor atomic fluorescence spectrometry, and a data logger for signal integration. We compared the operation, performance, and reproducibility between our DAA and the traditional manual analytic method. Its advantages include the ease of operation, the high time resolution and precision (30 min sampling and <5% relative variation), and long-term stability (2 weeks). The DAA can determine DMHg in both the MBL and surface seawater. The estimated detection limits for DMHg with the DAA in the atmosphere and in surface seawater are 10 pg/m3 and 0.2 fM, respectively. The successful DAA field measurement in coastal waters indicates that it can help detect the low DMHg concentration in surface seawater, and the time series DMHg data helped our understanding of the DMHg behavior (sources and sinks) and its flux into the MBL. The comparison of DMHg concentration in various oceans also suggests that the coastal region had the lowest averaged DMHg, up to an order of magnitude lower than other ecosystems.

Pushing the temporal resolution in absorption and Zernike phase contrast nanotomography: enabling fast in situ experiments.

Hard X-ray nanotomography enables 3D investigations of a wide range of samples with high resolution (<100 nm) with both synchrotron-based and laboratory-based setups. However, the advantage of synchrotron-based setups is the high flux, enabling time resolution, which cannot be achieved at laboratory sources. Here, the nanotomography setup at the imaging beamline P05 at PETRA III is presented, which offers high time resolution not only in absorption but for the first time also in Zernike phase contrast. Two test samples are used to evaluate the image quality in both contrast modalities based on the quantitative analysis of contrast-to-noise ratio (CNR) and spatial resolution. High-quality scans can be recorded in 15 min and fast scans down to 3 min are also possible without significant loss of image quality. At scan times well below 3 min, the CNR values decrease significantly and classical image-filtering techniques reach their limitation. A machine-learning approach shows promising results, enabling acquisition of a full tomography in only 6 s. Overall, the transmission X-ray microscopy instrument offers high temporal resolution in absorption and Zernike phase contrast, enabling in situ experiments at the beamline.

Fast Gas-Solid Reaction Kinetics of Nanoparticles Unveiled by Millisecond In†Situ Electron Diffraction at Ambient Pressure.

Acquiring the kinetics of gas-nanoparticle fast reactions under ambient pressure is a challenge owing to the lack of appropriate in situ techniques. Now an approach has been developed that integrates time-resolved in situ electron diffraction and an atmospheric gas cell system in transmission electron microscopy, allowing quantitative structural information to be obtained under ambient pressure with millisecond time resolution. The ultrafast oxidation kinetics of Ni nanoparticles in oxygen was vividly obtained. In contrast to the well-accepted Wagner and Mott-Cabrera models (diffusion-dominated), the oxidation of Ni nanoparticles is linear at the initial stage (<0.5 s), and follows the Avrami-Erofeev model (n=1.12) at the following stage, which indicates the oxidation of Ni nanoparticles is a nucleation and growth dominated process. This study gives new insights into Ni oxidation and paves the way to study the fast reaction kinetics of nanoparticles using ultrafast in situ techniques.

An oxygen isotope chronometer for cellulose deposition: the successive leaves formed by tillers of a C4 perennial grass.

Multiannual time series of (palaeo)hydrological information can be reconstructed from the oxygen isotope composition of cellulose (δ18 OCel ) in biological archives, for example, tree rings, but our ability to temporally resolve information at subannual scale is limited. We capitalized on the short and predictable leaf appearance interval (2.4 d) of a perennial C4 grass (Cleistogenes squarrosa), to assess its potential for providing highly time-resolved δ18 OCel records of vapour pressure deficit (VPD). Plants grown at low (0.63 kPa) or high (1.58 kPa) VPD were swapped between VPD environments and exposed to the new environment for 7 d with simultaneous 13 CO2 labelling. Then, leaves were sampled by age/position along individual tillers. Five leaves at different developmental stages were growing simultaneously. The period of most-active leaf elongation, from 10 to 90% of final length, lasted 6.6 d, and ~80% of all carbon and oxygen incorporation in whole-leaf cellulose occurred within 7 d. Cellulose deposition stopped at (or shortly after) full leaf expansion. The direction of change, low-to-high or high-to-low VPD, had no differential effect on new oxygen and carbon incorporation in cellulose. Successive leaves produced by tillers of C. squarrosa provide a δ18 OCel record useful for reconstructions of short-term hydrological dynamics.

Initial bridges between two ribosomal subunits are formed within 9.4 milliseconds, as studied by time-resolved cryo-EM.

Association of the two ribosomal subunits during the process of translation initiation is a crucial step of protein synthesis. The two subunits (30S and 50S) of the bacterial 70S ribosome are held together by 12 dynamic bridges involving RNA-RNA, RNA-protein, and protein-protein interactions. The process of bridge formation, such as whether all these bridges are formed simultaneously or in a sequential order, is poorly understood. To understand such processes, we have developed and implemented a class of microfluidic devices that mix two components to completion within 0.4 ms and spray the mixture in the form of microdroplets onto an electron microscopy grid, yielding a minimum reaction time of 9.4 ms before cryofixation. Using these devices, we have obtained cryo-EM data corresponding to reaction times of 9.4 and 43 ms and have determined 3D structures of ribosomal subunit association intermediates. Molecular analyses of the cryo-EM maps reveal that eight intersubunit bridges (bridges B1a, B1b, B2a, B2b, B3, B7a, B7b, and B8) form within 9.4 ms, whereas the remaining four bridges (bridges B2c, B4, B5, and B6) take longer than 43 ms to form, suggesting that bridges are formed in a stepwise fashion. Our approach can be used to characterize sequences of various dynamic functional events on complex macromolecular assemblies such as ribosomes.

Time- and spatial-resolved XAFS spectroscopy in a single shot: new analytical possibilities for in situ material characterization.

A new concept that comprises both time- and lateral-resolved X-ray absorption fine-structure information simultaneously in a single shot is presented. This uncomplicated set-up was tested at the BAMline at BESSY-II (Berlin, Germany). The primary broadband beam was generated by a double multilayer monochromator. The transmitted beam through the sample is diffracted by a convexly bent Si (111) crystal, producing a divergent beam. This, in turn, is collected by either an energy-sensitive area detector, the so-called color X-ray camera, or by an area-sensitive detector based on a CCD camera, in θ-2θ geometry. The first tests were performed with thin metal foils and some iron oxide mixtures. A time resolution of lower than 1 s together with a spatial resolution in one dimension of at least 50 µm is achieved.

Time delay measurement in the frequency domain.

Pump-probe studies at synchrotrons using X-ray and laser pulses require accurate determination of the time delay between pulses. This becomes especially important when observing ultrafast responses with lifetimes approaching or even less than the X-ray pulse duration (∼100 ps). The standard approach of inspecting the time response of a detector sensitive to both types of pulses can have limitations due to dissimilar pulse profiles and other experimental factors. Here, a simple alternative is presented, where the frequency response of the detector is monitored versus time delay. Measurements readily demonstrate a time resolution of ∼1 ps. Improved precision is possible by simply extending the data acquisition time.

High-time resolution PM2.5 source apportionment assisted by spectrum-based characteristics analysis.

Characteristics extraction and anomaly analysis based on frequency spectrum can provide crucial support for source apportionment of PM2.5 pollution. In this study, an effective source apportionment framework combining the Fast Fourier Transform (FFT)- and Continuous Wavelet Transform (CWT)-based spectral analyses and Positive Matrix Factorization (PMF) receptor model is developed for spectrum characteristics extraction and source contribution assessment. The developed framework is applied to Beijing during the winter heating period with 1-h time resolution. The spectrum characteristics of anomaly frequency, location, duration and intensity of PM2.5 pollution can be captured to gain an in-depth understanding of source-oriented information and provide necessary indicators for reliable PMF source apportionment. The combined analysis demonstrates that the secondary inorganic aerosols make relatively high contributions (50.59 %) to PM2.5 pollution during the winter heating period in Beijing, followed by biomass burning, vehicle emission, coal combustion, road dust, industrial process and firework emission sources accounting for 15.01 %, 11.00 %, 10.70 %, 5.31 %, 3.88 %, and 3.51 %, respectively. The source apportionment result suggests that combining frequency spectrum characteristics with source apportionment can provide consistent rationales for understanding the temporal evolution of PM2.5 pollution, identifying the potential source types and quantifying the related contributions.

Simulation of ionization charge carrier cascade time and density for a new radiation detection method based on modulation of optical properties.

BACKGROUND: In time-of-flight PET, image quality and accuracy can be enhanced by improving the annihilation photon pair coincidence time resolution, which is the variation in the arrival time difference between the two annihilation photons emitted from each positron decay in the patient. Recent studies suggest direct detection of ionization tracks and their resulting modulation of optical properties, instead of scintillation, can improve the CTR significantly, potentially down to less than 10 ps CTR. However, the arrival times of the 511 keV photons are not predictable, leading to challenges in the spatiotemporal localization characterization of the induced charge carriers in the detector crystal. PURPOSE: To establish an optimized experimental setup for measuring ionization induced modulation of optical properties, it is critical to develop a versatile simulation algorithm that can handle multiple detector material properties and time-resolved charge carrier dynamics. METHODS: We expanded our previous algorithm and simulated ionization tracks, cascade time and induced charge carrier density over time in different materials. For designing a proof-of-concept experiment, we simulated ultrafast electrons and free-electron x-ray photons for timing characterization along with alpha and beta particles for higher spatial localization. RESULTS: With 3 MeV ultrafast electrons, by reducing detector crystal thickness, we can effectively reduce the ionization cascade time to 0.79 ps and deposited energy to 198.5 keV, which is on the order of the desired 511 keV energy. Alpha source simulations produced a cascade time of 2.45 ps and charge carrier density of 6.39 × 1020 cm-3 . Compared to the previous results obtained from 511 keV photon-induced ionization track simulations, the cascade time displayed similar characteristics, while the charge density was found to be higher. These findings suggest that alpha sources have the potential to generate a stronger ionization-induced signal using the modulation of optical properties as the detection mechanism. CONCLUSIONS: This work provides a guideline to understand, design and optimize an experimental platform that is highly sensitive and temporally precise enough to detect single 511 keV photon interactions with a goal to advance CTR for ToF-PET.

Enhancing timing performance of heterostructures with double-sided readout.

Objective.Heterostructured scintillators offer a promising solution to balance the sensitivity and timing in TOF-PET detectors. These scintillators utilize alternating layers of materials with complementary properties to optimize performance. However, the layering compromises time resolution due to light transport issues. This study explores double-sided readout-enabling improved light collection and Depth-of-Interaction (DOI) information retrieval-to mitigate this effect and enhance the timing capabilities of heterostructures.Approach.The time resolution and DOI performances of 3 × 3 × 20 mm3BGO&EJ232 heterostructures were assessed in a single and double-sided readout (SSR and DSR, respectively) configuration using high-frequency electronics.Main results.Selective analysis of photopeak events yielded a DOI resolution of 6.4 ± 0.04 mm. Notably, the Coincidence Time Resolution (CTR) improved from 262 ± 8 ps (SSR) to 174 ± 6 ps (DSR) when measured in coincidence with a fast reference detector. Additionally, symmetrical configuration of two identical heterostructures in coincidence was tested, yielding in DSR a CTR of 254 ± 8 ps for all photopeak events and 107 ± 5 ps for the fastest events.Significance.By using high-frequency double-sided readout, we could measure DOI resolution and improve the time resolution of heterostructures of up to 40%. The DOI information resulted intrinsically captured in the average between the timestamps of the two SiPMs, without requiring any further correction.

Study of modulation in complex refractive indices induced by ultrafast relativistic electrons using infrared and THz probe pulses.

Objective Achieving ultra-precise temporal resolution in ionizing radiation detection is essential, particularly in positron emission tomography, where precise timing enhances signal-to-noise ratios and may enable reconstruction-less imaging. A promising approach involves utilizing ultrafast modulation of the complex refractive index, where sending probe pulses to the detection crystals will result in changes in picoseconds (ps), and thus a sub - 10 ps coincidence time resolution can be realized. Towards this goal, here, we aim to first measure the ps changes in probe pulses using an ionizing radiation source with high time resolution. Approach We used relativistic, ultrafast electrons to induce complex refractive index and use probe pulses in the near-infrared (800 nm) and terahertz (THz, 300 µm) regimes to test the hypothesized wavelength-squared increase in absorption coefficient in the Drude free-carrier absorption model. We measured BGO, ZnSe, BaF2, ZnS, PBG, and PWO with 1 mm thickness to control the deposited energy of the 3 MeV electrons, simulating ionization energy of the 511 keV photons. Main results Both with the 800 nm and THz probe pulses, transmission decreased across most samples, indicating the free carrier absorption, with an induced signal change of 11% in BaF2, but without the predicted Drude modulation increase. To understand this discrepancy, we simulated ionization tracks and examined the geometry of the free carrier distribution, attributing the mismatch in THz modulations to the sub-wavelength diameter of trajectories, despite the lengths reaching 500 µm to 1 mm. Additionally, thin samples truncated the final segments of the ionization tracks, and the measured initial segments have larger inter-inelastic collision distances due to lower stopping power (dE/dx) for high-energy electrons, exacerbating diffraction-limited resolution. Significance Our work offers insights into ultrafast radiation detection using complex refractive index modulation and highlights critical considerations in sample preparation, probe wavelength, and probe-charge carrier coupling scenarios.

A pilot study to assess the origin of the spectral power increases of heart rate variability associated with transient changes in the R-R interval.

Spectral analysis of heart rate variability (HRV) is used to assess cardiovascular autonomic function. In the power density spectrum calculated from a time series of the R-R interval (RRI), three main components are distinguished: very-low-frequency (VLF; 0.003-0.04 Hz), low-frequency (LF; 0.04-0.15 Hz), and high-frequency (HF; 0.15-0.4 Hz) components. However, the physiological correlates of these frequency components have yet to be determined. In this study, we conducted spectral analysis of data segments of various lengths (5, 30, 100, and 200 s) of the RRI time series during active standing. Because of the trade-off relationship between time and frequency resolution, the analysis of the RRI data segment shorter than 30 s was needed to identify the temporal relationships between individual transient increases in RRI and the resulting spectral power changes. In contrast, the segment of 200 s was needed to properly evaluate the magnitude of the increase in the VLF power. The results showed that a transient increase in the RRI was tightly associated with simultaneous increases in the powers of the VLF, LF, and HF components. We further found that the simultaneous power increases in these three components were caused by the arterial baroreceptor reflex responding to rapid blood pressure rise.

Performance evaluation of the FastIC readout ASIC with emphasis on Cherenkov emission in TOF-PET.

Objective.The efficient usage of prompt photons like Cherenkov emission is of great interest for the design of the next generation, cost-effective, and ultra-high-sensitivity time-of-flight positron emission tomography (TOF-PET) scanners. With custom, high power consuming, readout electronics and fast digitization the prospect of sub-300 ps FWHM with PET-sized BGO crystals have been shown. However, these results are not scalable to a full system consisting of thousands of detector elements.Approach.To pave the way toward a full TOF-PET scanner, we examine the performance of the FastIC ASIC with Cherenkov-emitting scintillators (BGO), together with one of the most recent SiPM detector developments based on metal trenching from FBK. The FastIC is a highly configurable ASIC with 8 input channels, a power consumption of 12 mW ch-1and excellent linearity on the energy measurement. To put the timing performance of the FastIC into perspective, comparison measurements with high-power consuming readout electronics are performed.Main results.We achieve a best CTR FWHM of 330 ps for 2 × 2 × 3 mm3and 490 ps for 2 × 2 × 20 mm3BGO crystals with the FastIC. In addition, using 20 mm long LSO:Ce:Ca crystals, CTR values of 129 ps FWHM have been measured with the FastIC, only slightly worse to the state-of-the-art of 95 ps obtained with discrete HF electronics.Significance.For the first time, the timing capability of BGO with a scalable ASIC has been evaluated. The findings underscore the potential of the FastIC ASIC in the development of cost-effective TOF-PET scanners with excellent timing characteristics.

Methods in molecular photocrystallography.

Over the last three decades, the technology that makes it possible to follow chemical processes in the solid state in real time has grown enormously. These studies have important implications for the design of new functional materials for applications in optoelectronics and sensors. Light-matter interactions are of particular importance, and photocrystallography has proved to be an important tool for studying these interactions. In this technique, the three-dimensional structures of light-activated molecules, in their excited states, are determined using single-crystal X-ray crystallography. With advances in the design of high-power lasers, pulsed LEDs and time-gated X-ray detectors, the increased availability of synchrotron facilities, and most recently, the development of XFELs, it is now possible to determine the structures of molecules with lifetimes ranging from minutes down to picoseconds, within a single crystal, using the photocrystallographic technique. This review discusses the procedures for conducting successful photocrystallographic studies and outlines the different methodologies that have been developed to study structures with specific lifetime ranges. The complexity of the methods required increases considerably as the lifetime of the excited state shortens. The discussion is supported by examples of successful photocrystallographic studies across a range of timescales and emphasises the importance of the use of complementary analytical techniques in order to understand the solid-state processes fully.

Bright Innovations: Review of Next-Generation Advances in Scintillator Engineering.

This review focuses on modern scintillators, the heart of ionizing radiation detection with applications in medical diagnostics, homeland security, research, and other areas. The conventional method to improve their characteristics, such as light output and timing properties, consists of improving in material composition and doping, etc., which are intrinsic to the material. On the contrary, we review recent advancements in cutting-edge approaches to shape scintillator characteristics via photonic and metamaterial engineering, which are extrinsic and introduce controlled inhomogeneity in the scintillator's surface or volume. The methods to be discussed include improved light out-coupling using photonic crystal (PhC) coating, dielectric architecture modification producing the Purcell effect, and meta-materials engineering based on energy sharing. These approaches help to break traditional bulk scintillators' limitations, e.g., to deal with poor light extraction efficiency from the material due to a typically large refractive index mismatch or improve timing performance compared to bulk materials. In the Outlook section, modern physical phenomena are discussed and suggested as the basis for the next generations of scintillation-based detectors and technology, followed by a brief discussion on cost-effective fabrication techniques that could be scalable.

Monitoring data from an office room in a real operating building, suitable for state-space energy modelling.

The dataset provides all necessary variables for data-driven energy modelling of an office room. The measurement data have been obtained from an office building operating as living lab in a temperate climate of Central Europe. The temperatures and the ventilation air flowrate are raw measurements, while the heat flows are calculated from measurements. The incoming solar irradiance is calculated with two façade models -simple and enhanced-, using measurements (solar irradiance, movable shading settings) and building characteristics (geometry, glazing and shading properties). One year and four months of data is provided with a fine one-minute time step and a coarser fifteen-minute time step. The dataset can be used to test and validate data-driven models, for example for predictive control applications.

Evaluation of the Timing Properties of a High Quantum Efficiency Photomultiplier Tube.

We measured the timing resolution of 189 R9800-100 photomultiplier tubes (PMTs), which are a SBA (Super Bialkali, high quantum efficiency) variant of the R9800 high-performance PMT manufactured by Hamamatsu Photonics, and correlated their timing resolutions with various measures of PMT performance, namely Cathode Luminous Sensitivity (CLS), Anode Luminous Sensitivity (ALS), Gain times Collection Efficiency (GCE), Cathode Blue Sensitivity Index (CBSI), Anode Blue Sensitivity Index (ABSI) and dark current. The correlation results show: (1) strong correlations between timing resolution and ALS, ABSI, and GCE; (2) moderate correlations between timing resolution and CBSI; and (3) weak or no correlations between timing resolution and dark current and CLS. The results disclosed that all three measures that include data collected from the anode (ALS, ABSI, and GCE) affect the timing resolution more than either of the two measures that only include photocathode data (CBSI and CLS). We conclude that: (1) the photocathode Quantum Efficiency (QE) and the product of the Gain and the Collection Efficiency (GCE) are the two dominant factors that affect the timing resolution, (2) the GCE variation affects the timing resolution more than the QE variation in the R9800 PMT, and (3) the performance depends on photocathode position.