High-power picosecond UV and deep-UV laser sources delivering powers of 30 W at 355 nm, 10 W at 266 nm, and 5 W at 213 nm.

Utilizing LiBO, -BaBO crystals, and an Nd:YVO laser with an average power of 70 W and a repetition rate of 100 kHz, we systematically demonstrated and operated high-repetition-rate, high-power, all-solid-state, UV, and deep-UV picosecond laser sources via high-efficiency third-, fourth-, and fifth-harmonic generation (THG, FHG, and FiHG). The maximum output powers of the radiation at 355, 266, and 213 nm reached 31.2, 10.

Association of hydration status and in-hospital mortality in critically ill patients with ischemic stroke: Data from the MIMIC-IV database.

Background: Hydration plays a critical role in the pathophysiological progression of ischemic stroke. However, the impact of extreme hydration on the mortality of critically ill patients with ischemic stroke remains unclear. Therefore, our objective was to evaluate the association between hydration, as indicated by the blood urea nitrogen to creatinine ratio (UCR), and in-hospital mortality in critically ill patients with ischemic stroke.

High-precision spatiotemporal three-dimensional ultrashort pulse synchronization with optical Kerr effect.

In studying the interaction of multiple ultrashort pulses with matter, high requirements are put forward for spatiotemporal synchronization accuracy. Limited by the response time and bandwidth of existing devices, the synchronization of multiple ultrashort pulses still faces significant difficulties. By observing the transient phenomena of the optical Kerr effect, high-precision, three-dimensional (x, y, t) synchronization of ultrashort pulses at different angles was achieved.

Is Fe the Most Active Site for Fe/N-Doped Graphdiyne?

We performed a systematic study on the activity of pristine, Fe-doped, N-doped, and Fe/N-codoped graphdiyne (GDY) for oxygen reduction reactions (ORRs). We found that the pristine GDY has a high overpotential because of the weak binding of the intermediates. The sp-hybridized N-doped GDY enhances the binding of the intermediates at the adjacent sp-hybridized C site, which greatly enhances its ORR activities with a low overpotential of 0.

Mitigation of electromagnetic pulses interfering with Thomson parabola ion spectrometers at XG-III laser facility.

The Thomson parabola ion spectrometer is vulnerable to intense electromagnetic pulses (EMPs) generated by a high-power laser interacting with solid targets. A metal shielding cage with a circular aperture of 1 mm diameter is designed to mitigate EMPs induced by a picosecond laser irradiating a copper target in an experiment where additionally an 8-ns delayed nanosecond laser is incident into an aluminum target at the XG-III laser facility. The implementation of the shielding cage reduces the maximum EMP amplitude inside the cage to 5.

Variables related to bronchopulmonary dysplasia severity: a Six-Year retrospective study.

Objectives: This was a retrospective observational study conducted in a tertiary neonatal intensive care unit, in order to investigate factors which influenced the severity of bronchopulmonary dysplasia under NICHD new classification.

Methods: Six years of clinical data with different grades of bronchopulmonary dysplasia patients were collected and analyzed, bivariate ordinal logistic regression model and multivariable ordinal logistic regression model were used with sensitivity analyses.

Results: We identified seven variables were associated with the severity of BPD a bivariate ordinal logistic regression model, including the level of referral hospital (OR 0.

High-peak-power picosecond deep-UV laser sources.

Ultrafast deep-UV laser sources have extensive applications across a wide number of fields, whether biomedicine, photolithography, industrial processing, or state-of-the-art scientific research. However, it has been challenging to obtain deep-UV laser sources with high conversion efficiency and output peak power. Here, we simultaneously demonstrated high-peak-power picosecond deep-UV laser sources at two typical wavebands of 263.

A potential pathogenic hypoxia-related gene HK2 in necrotizing enterocolitis (NEC) of newborns.

Background: Necrotizing enterocolitis (NEC) is a disastrous gastrointestinal disease of newborns, and the mortality rate of infants with NEC is approximately 20%-30%. The exploration of pathogenic targets of NEC will be conducive to timely diagnosis of NEC.

Methods: The whole transcriptome RNA sequencing was performed on NEC samples to reveal the expression of lncRNAs, circRNAs, miRNAs and mRNAs.

Corrigendum to "Long-term L-3-n-butylphthalide pretreatment attenuates ischemic brain injury in mice with permanent distal middle cerebral artery occlusion through the Nrf2 pathway" [Heliyon 8 (7), (July 2022), Article e09909].

[This corrects the article DOI: 10.1016/j.heliyon.

Modulation of laser damage by temporal shaping of double picosecond pulses.

We propose a temporally shaped double-picosecond-pulse train at a sub-nanosecond scale to control the damage dynamics of optical glass. Both damage threshold and morphology are significantly modulated by pulse-train shaping. The ramp-up-shaped train effectively increases its damage threshold and decreases the damage density and size, which clearly shows that a pump pulse with optimized fluence has a strong positive modification of damage precursors.

Long-term L-3-n-butylphthalide pretreatment attenuates ischemic brain injury in mice with permanent distal middle cerebral artery occlusion through the Nrf2 pathway.

L-3-n-butylphthalide (NBP), which is used for treatment of mild and moderate acute ischemic stroke, exerts its effects by modulating the Nrf2 pathway. However, it has not been established whether NBP exerts its preventive effects in high-risk ischemic stroke patients through the Nrf2 pathway. We investigated whether NBP exerts its preventive effects through the Nrf2 pathway in long-term NBP pretreated dMCAO mice models.

Noncritical phase-matching fourth- and fifth-harmonic generation of 1077 nm laser using KDP-family crystals.

We systematically demonstrated the angular and temperature acceptances of noncritical phase-matching (NCPM) fourth- and fifth-harmonic generation (FHG and FiHG) of a 1077 nm laser in NHHPO (ADP), KHPO (KDP), and KDPO (DKDP) crystals. In this work, a new, to the best of our knowledge, laser frequency with a wavelength of 1077 nm was generated by optical parametric amplification, in which the pump light (526.3 nm) was generated by the frequency doubling of a Nd:YLF laser (1052.

Understanding and optimizing diffraction gratings by the blazing analysis of total internal reflection.

The diffraction grating is a classic and important optical element, and its design usually traverses the whole parameter space to search for an optimal solution, which is time consuming and inefficient. In order to specify the optimization direction of the grating to obtain clearer physical images and to improve the design efficiency, a new blazing model based on the total internal reflection (TIR) is proposed to analyze the diffraction behavior of the grating from a geometry perspective. The optical tunnel along the ridge direction can be used to understand and quantify the blaze of the grating.

Electro-optic coefficient measurement of a K(HD)PO crystal based on χ nonlinear optical technology.

We present a novel method utilizing the χ nonlinear optical technology, which can realize high precision measurement of linear electro-optic (EO) coefficients of nonlinear materials. By applying the linear EO effect to the nonlinear optical process, the theoretical model of this measurement method was established, and the calculation formula of the linear EO coefficient was given. In the proof-of-principle experiment, by introducing an external electric field into the fourth harmonic generation (FHG) process, we comprehensively obtained the linear EO coefficients of K(HD)PO crystals and revealed the relationship between deuterium content (x) and EO coefficient (γ): γ = -9.

Defect edge steepness dependence of multiple nonlinear hot-image formation from a single phase defect.

Nonlinear hot image is one of the key elements that limit the output performance of high-power laser systems. In most hot-image researches, only one hot image peak is observed in the conjugate position for a single defect. Generally, multiple hot image peaks occur for multiple defects or cascaded nonlinear media.

First-principles study on the selective hydrogenation of the C[double bond, length as m-dash]O and C[double bond, length as m-dash]C bonds of acrolein on Pt-M-Pt (M = Pt, Cu, Ni, Co) surfaces.

Selective hydrogenation of the C[double bond, length as m-dash]O and C[double bond, length as m-dash]C bonds of acrolein on Pt-M-Pt (M = Pt, Cu, Ni, Co) surfaces has been investigated with first-principles calculations to understand the trends of the activity and selectivity of the reaction. On the pristine Pt(111) surface, the results suggest that the production of allyl alcohol (a product of C[double bond, length as m-dash]O bond hydrogenation) is limited by its desorption, which results in the selective hydrogenation of the C[double bond, length as m-dash]C bond. On the other three bimetallic surfaces, the results show that the desorption of the product is no longer rate-limiting, and the reaction should be selective for the C[double bond, length as m-dash]O bond hydrogenation.

Phase defect detection of large-aperture optics with static multiplanar coherent diffraction imaging.

Phase defect detection with micrometer scale on large aperture optical elements is one of the challenges in precision optical systems. An efficient scheme is proposed to detect phase defects. First, the defects are positioned in a large aperture by dark-field imaging based on large aperture photon sieves to improve the detection efficiency with a relatively low cost.

Interleukin 17 is an important pathogenicity gene in pediatric sepsis.

Objective: Sepsis represents a complex disease with the dysregulated inflammatory response. The purpose of this study is to explore the role of interleukin 17 (IL-17, also known as IL-17A) in the occurrence and development of pediatric sepsis.

Methods: We established the sepsis neonatal rat model with the method of intraperitoneal injection of Escherichia coli (E coli).

Determination of the damage growth threshold of multilayer dielectric gratings by picosecond laser pulses based on saturation damage size analysis.

We propose two efficient methods of determining damage growth threshold (DGT) based on the saturation damage size analysis (SDSA) for multilayer dielectric gratings by picosecond pulsed lasers. The damage size at laser fluences above DGT increases with the shot number and finally saturates due to the Gaussian focal spot. The DGT is extracted by mapping the boundary of a saturation damage site obtained at single fluence to the beam profile, which is called the monofluence SDSA method.

Asymmetrical damage growth of multilayer dielectric gratings induced by picosecond laser pulses.

We experimentally investigated the laser damage growth behavior of multilayer dielectric gratings (MLDGs) by the picosecond pulses at 1053nm. The damage growth threshold of 2.43J/cm is significantly lower than the 20/1 damage threshold of 3.

Temperature-insensitive frequency conversion by phase mismatch self-compensation in the same type of crystals.

Aiming at high-power laser frequency conversion, we present a new scheme that can self-compensate for the thermally induced phase mismatch. The basic design of the scheme is that three crystals with the same type are cascaded, of which the crystals at both ends are used for frequency conversion and the middle crystal is used for compensating phase mismatch. By configuring the polarization states of the interacting waves in the middle crystal, the sign of the first temperature derivative of the phase mismatch is opposite to that of the frequency conversion crystals.

Structural evolution of axial intensity distribution during hot image formation.

The structural evolution of the axial intensity distribution during hot image formation perturbed by a small circular optical obscuration is investigated in detail under different conditions. An analytic expression is derived for the axial intensity distribution around the conjugate plane by assuming the thickness of the nonlinear medium to be infinitely small. In view of the analysis of the axial intensity oscillation, the expression can be extensively utilized to characterize the intensity maxima for a nonlinear medium with a finite thickness.

Numerical analysis of laser ablation and damage in glass with multiple picosecond laser pulses.

This study presents a novel numerical model for laser ablation and laser damage in glass including beam propagation and nonlinear absorption of multiple incident ultrashort laser pulses. The laser ablation and damage in the glass cutting process with a picosecond pulsed laser was studied. The numerical results were in good agreement with our experimental observations, thereby revealing the damage mechanism induced by laser ablation.