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The cingulum bundle (CB) is a group of axons supporting connectivity among several functional brain networks relevant in healthy and diseased states. The paracingulate sulcus (PCS) is present in at least one cerebral hemisphere across 70% of the population. PCS presence versus absence is linked to differences in structure and function of the anterior cingulate cortex, though the influence of PCS on the white matter of the CB remains unknown. The objective of this work was to define the CB electrographic connectivity profile and determine the impact of PCS morphology on CB engagement. Single‐pulse electrical stimulation in combination with stereo‐electroencephalography recordings was used to measure neural responses to left and right CB stimulation in 19 patients undergoing intracranial monitoring for treatment of refractory epilepsy. Evoked potential responses were extracted from brain areas, and a connectivity robustness ratio was computed. Network‐level responses were compared across left and right CB, and with consideration of PCS morphology. CB electrographic connectivity demonstrated leftward dominance, but this was strongly impacted by PCS morphology in both cerebral hemispheres. Maximal left CB connectivity was observed in the presence of left PCS morphology, while right CB connectivity was strongest in its absence. These data strongly suggest that bilateral CB engagement is modulated by PCS morphology in the left hemisphere. These findings are particularly relevant when considering the CB as a target for treating neuropsychiatric disorders. Electrical stimulation reveals hemispheric asymmetry in cingulum bundle connectivity, which is further modulated by variability in paracingulate sulcus morphology. Differences in cingulum bundle connectivity across hemispheres may support functional specialization, and the impact of paracingulate sulcus morphology may suggest differences in fiber organization.

It is now widely accepted that seizures arise from the coordinated activity of epileptic networks, and as a result, traditional methods of analyzing seizures have been augmented by techniques like single‐pulse electrical stimulation (SPES) that estimate effective connectivity in brain networks. We used SPES and graph analytics in 18 patients undergoing intracranial EEG monitoring to investigate effective connectivity between recording sites within and outside mesial temporal structures. We compared evoked potential amplitude, network density, and centrality measures inside and outside the mesial temporal region (MTR) across three patient groups: focal epileptogenic MTR, multifocal epileptogenic MTR, and non‐epileptogenic MTR. Effective connectivity within the MTR had significantly greater magnitude (evoked potential amplitude) and network density, regardless of epileptogenicity. However, effective connectivity between MTR and surrounding non‐epileptogenic regions was of greater magnitude and density in patients with focal epileptogenic MTR compared to patients with multifocal epileptogenic MTR and those with non‐epileptogenic MTR. Moreover, electrodes within focal epileptogenic MTR had significantly greater outward network centrality compared to electrodes outside non‐epileptogenic regions and to multifocal and non‐epileptogenic MTR. Our results indicate that the MTR is a robustly connected subnetwork that can exert an overall elevated propagative influence over other brain regions when it is epileptogenic. Understanding the underlying effective connectivity and roles of epileptogenic regions within the larger network may provide insights that eventually lead to improved surgical outcomes. Hays et al. utilize evoked potentials from single‐pulse electrical stimulation to map effective networks in mesial temporal epilepsy patients. Graph theoretical analysis of these connections is applied to characterize the role of mesial temporal structures within broader epileptogenic networks, revealing a highly hyperexcitable and influential densely connected subnetwork. This approach provides additional groundwork to better understand epilepsy as a network disorder and identify epileptogenic hubs of connectivity for network targeted treatments.

Activatable type I photosensitizers are an effective way to overcome the insufficiency and imprecision of photodynamic therapy in the treatment of hypoxic tumors, however, the incompletely inhibited photoactivity of pro‐photosensitizer and the limited oxidative phototoxicity of post‐photosensitizer are major limitations. It is still a great challenge to address these issues using a single and facile design. Herein, a series of totally caged type I pro‐photosensitizers (Pro‐I‐PSs) are rationally developed that are only activated in tumor hypoxic environment and combine two oxygen‐independent therapeutic mechanisms under single‐pulse laser irradiation to enhance the phototherapeutic efficacy. Specifically, five benzophenothiazine‐based dyes modified with different nitroaromatic groups, BPN 1−5, are designed and explored as latent hypoxia‐activatable Pro‐I‐PSs. By comparing their optical responses to nitroreductase (NTR), it is identified that the 2‐methoxy‐4‐nitrophenyl decorated dye (BPN 2) is the optimal Pro‐I‐PSs, which can achieve NTR‐activated background‐free fluorescence/photoacoustic dual‐modality tumor imaging. Furthermore, upon activation, BPN 2 can simultaneously produce an oxygen‐independent photoacoustic cavitation effect and a photodynamic type I process at single‐pulse laser irradiation. Detailed studies in vitro and in vivo indicated that BPN 2 can effectively induce cancer cell apoptosis through synergistic effects. This study provides promising potential for overcoming the pitfalls of hypoxic‐tumor photodynamic therapy. Enhancement of the accuracy and efficiency of activatable type I pro‐photosensitizers (Pro‐I‐PSs) in a simple and effective way remains greatly challenging. Given this, the Pro‐I‐PS BPN 2 is developed with the following features: 1) Simple and well‐defined molecular structure; 2) NTR‐triggered dramatic transition of photoactivity from completely inhibited state to highly activated state; 3) high‐contrast fluorescence/photoacoustic imaging‐guided oxygen‐independent synergistic phototherapy.

Rapid detection of soil nutrient elements is beneficial to the evaluation of crop yield, and it’s of great significance in agricultural production. The aim of this work was to compare the detection ability of single-pulse (SP) and collinear double-pulse (DP) laser-induced breakdown spectroscopy (LIBS) for soil nutrient elements and obtain an accurate and reliable method for rapid detection of soil nutrient elements. 63 soil samples were collected for SP and collinear DP signal acquisition, respectively. Macro-nutrients (K, Ca, Mg) and micro-nutrients (Fe, Mn, Na) were analyzed. Three main aspects of all elements were investigated, including spectral intensity, signal stability, and detection sensitivity. Signal-to-noise ratio (SNR) and relative standard deviation (RSD) of elemental spectra were applied to evaluate the stability of SP and collinear DP signals. In terms of detection sensitivity, the performance of chemometrics models (univariate and multivariate analysis models) and the limit of detection (LOD) of elements were analyzed, and the results indicated that the DP-LIBS technique coupled with PLSR could be an accurate and reliable method in the quantitative determination of soil nutrient elements.

We demonstrate a thulium (Tm)-doped fibre amplifier using a Ho: GdVO 4 solid-state laser as the master oscillator operating at 2048.53 nm. In experiment, a novel spatial coupling system was used, combining a single lens with a curved end cap to simplify the structure and reduce losses. The integrated fibre end cap design effectively protected the fibre core from damage caused by high-energy short-pulse seed lasers. The power amplifier (PA) stage adopted backward pumping to directly achieve pure laser output. In continuous wave (CW) mode, a maximum laser output power of 33.4 W was obtained under a maximum pump power of 151 W injection at 18 °C. The slope efficiency of the amplification stage was 19.5%. The output laser wavelength was 2048.57 nm, and the full width at half maximum (FWHM) was 0.14 nm. In Q-switched mode, a maximum single pulse energy of 3.86 mJ was obtained at a pulse repetition frequency (PRF) of 5 kHz with a pulse width of 22.1 ns, corresponding to a peak power of 174.7 kW and an average output power of 19.3 W. No nonlinear optical effects, such as stimulated Raman scattering (SRS) or stimulated Brillouin scattering (SBS) was observed throughout the experiment, and the fibre amplifier output remained stable. Ultimately, the maximum single pulse energy obtained by a 2.05 μm backward-pumped Tm-doped fibre amplifier (TDFA) at a PRF of 5 kHz and a pulse width of 22.1 ns was 3.86 mJ.

Single bubble sonoluminescence (SBSL) is the phenomenon of synchronous light emission due to the violent collapse of a single spherical bubble in a liquid, driven by an ultrasonic field. During the bubble collapse, matter inside the bubble reaches extreme conditions of several gigapascals and temperatures on the order of 10000 K, leading to picosecond flashes of visible light. To this day, details regarding the energy focusing mechanism rely on simulations due to the fast dynamics of the bubble collapse and spatial scales below the optical resolution limit. In this work we present phase-contrast holographic imaging with single x-ray free-electron laser (XFEL) pulses of a SBSL cavitation bubble in water. X-rays probe the electron density structure and by that provide a uniquely new view on the bubble interior and its collapse dynamics. The involved fast time-scales are accessed by sub-100 fs XFEL pulses and a custom synchronization scheme for the bubble oscillator. We find that during the whole oscillation cycle the bubble’s density profile can be well described by a simple step-like structure, with the radius R following the dynamics of the Gilmore model. The quantitatively measured internal density and width of the boundary layer exhibit a large variance. Smallest reconstructed bubble sizes reach down to R ≃ 0.8 μ m , and are consistent with spherical symmetry. While we here achieved a spatial resolution of a few 100 nm, the visibility of the bubble and its internal structure is limited by the total x-ray phase shift which can be scaled with experimental parameters.

Cortico-cortical evoked potentials (CCEPs) are electrophysiological responses elicited by direct electrical stimulation of one cortical region and recorded from another, providing insights into functional connectivity and communication pathways between brain areas. However, no consistent standard for defining and measuring CCEPs currently exists. We conducted a systematic review of the CCEP literature on detection methods to evaluate commonalities and gaps in methodology. Extracted data included demographics, disease, recording type, montage, recording system, stimulation amplitude and frequency, time window used for epoching around stimulus onset, open access availability, and detection approach. Of 187 studies undergoing full-text review, over half lacked a description of the CCEP detection method. Specifically, 9.1% utilized visual identification, whereas 49.74% did not explicitly state the method. The remaining 72 studies represented 3,424 patients, of whom 58.3% had sEEG electrodes and most had epilepsy. The most common detection method was threshold-based (68.1%), followed by statistical testing (16.7%) to determine whether CCEPs differed significantly from baseline, data-driven methods (4.1%) that quantify responses after learning from data, and frequency-based approaches (4.1%). Bipolar (48.6%) and single-electrode referential montages (18.1%) were most frequently employed. Current CCEP detection methods lack consensus, with many studies omitting methodological details and relying heavily on threshold-based techniques that assume fixed response shapes. Future research should encourage the use of data-driven approaches, which learn directly from data, offer more robust alternatives, and improve quantification in both clinical and research contexts. https://www.crd.york.ac.uk/PROSPERO/view/CRD42024568261, identifier CRD42024568261.

Enhancing the drive current of oxide semiconductor transistors is crucial for enabling high-resolution displays with thin bezels and improving memory write and access speeds. High-mobility channel materials boost drive current but typically require stricter process control and reliability, presenting mass-production challenges compared to stable materials like InGaZnO. Therefore, increasing drive current without changing the channel material is a desirable goal to pursue. One approach is to enhance gate capacitance using high-κ gate dielectrics. In this study, we systematically investigate the impact of high-κ gate dielectrics on the performance of InGaZnO transistors, focusing on three different gate insulators: SiO 2 , HfO 2 , and ZrO 2 . Experimental results show that as the dielectric constant increases from 3.9 (SiO 2 ) to 17 (HfO 2 ) and 30 (ZrO 2 ), the drive current is enhanced by factors of 2.8 and 7, respectively–less than the expected enhancement from κ alone. Device simulations reveal that contact resistance, channel capacitance, and interface trap density all influence the drive current. Notably, interface traps emerge as the primary limiting factor, particularly in HfO 2 , significantly degrading the transconductance. Utilizing the single-pulse charge pumping method, we quantify interface trap densities and demonstrate that reducing interface traps is essential in fully leveraging high-κ gate dielectrics to enhance drive current.

•We stimulated primary motor cortex (M1) in awake rhesus macaques using sp-TMS.•Recruitment curves (RC) were measured with a motor evoked potential (MEP) readout.•Traditional motor threshold (tradMT, at 100 µV) was near the RC inflection point.•A physiologically relevant motor response threshold was found at 90 % of the tradMT.•Plateau of the RC appears at smaller amplitudes in macaques compared to humans. Cortical excitability (CE) is commonly assessed via motor evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (sp-TMS). While the motor threshold (MT) remains the most widely used measure of CE, it provides a limited, one-dimensional measure based on a fixed MEP amplitude criterion. In contrast, the recruitment curve (RC) offers a more comprehensive characterization of corticospinal recruitment dynamics. To date, the few available preclinical TMS studies measuring RC in non-human primates have been conducted under anaesthesia with limited translational relevance. Hence, we characterised CE in 20 sessions of 4 awake rhesus macaques by recording RCs at nine stimulation intensity levels and parametrising them using exponentiated sigmoid functions. The traditional 100 µV MEP MT criterion level (SI100µV) aligned most closely with the inflection point of the RC sigmoid fit and was consistent with relative frequency-based traditional MT (tradMT) measured in separate sessions. The onset of the logarithmic recruitment phase of the sigmoid (lower ankle point) was found at 0.9 × SI100µV/tradMT. Well-formed MEPs were measured below the SI100µV/tradMT, but not below the lower ankle point, which is a physiologically relevant response threshold. Thus, in rhesus macaques the 100-µV criterion may be suitable to approximate the RC inflection point, but not the physiological motor threshold. The overall RC shape was consistent with previous human data, however, plateau MEP amplitudes were substantially smaller than those reported in humans. These results lay the groundwork for the adaptation of TMS protocols and CE metrics to non-human primates that is necessary for translationally valid research.

To address the problems of high process complexity, uncontrollable and unpredictable wetting performance, and expensive processing equipment for the superhydrophobic surfaces of metal substrates prepared by conventional methods, in this paper, superhydrophobic surfaces consisting of rectangular cross-section double-scale arrays of microstructure were prepared on HT250 substrates using wire electrical discharge machining (WEDM). First, a simulation model of the surface wetting performance of the rectangular cross-section double-scale array microstructure prepared by WEDM is established, to analyze the effect of peak current and pulse width on the surface roughness, dimensional parameters, and surface wetting performance of the discharge micro-crater structure; the effect of the width and distance of the rectangular cross-section on the surface wetting performance of the double-scale array of microstructure with rectangular cross-section is further discussed. And the simulation model is experimentally verified. The results of the study in this paper indicate that at a peak current of 12A, a pulse width of 20 μs, and a rectangular cross-section with a width and distance of 200 μm, the contact angles of the rectangular cross-section double-scale array microstructure surface obtained from simulation and experiment are 133° and 135.3°, respectively, the prediction accuracy of the simulation model is 98.3%, and the surface has superhydrophobic performance after low surface energy treatment, with a static contact angle of 151.5°. This study not only extends the application area of WEDM, but also provides a theoretical reference for the design of metal substrate microstructure surface, realizes the controllable preparation and accurate prediction of wetting performance of metal substrate microstructure surface, and has important guiding significance for the preparation of metal substrate superhydrophobic surfaces.