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Purpose: The relationship between serum albumin levels and severe limitations in ADLs among stroke patients remains unclear. Specifically, the dose–response relationship between the two needs further exploration. This study aims to provide further results. Materials and methods: This study examined cross-sectional data from patients aged 18 years or older with a diagnosis of stroke confirmed by cranial CT or MRI within 24 h of admission, gathered from January 2020 to August 2022. Data included serum albumin levels, Barthel Index scores recorded after admission, and other essential variables. Results: The study comprised 2,393 stroke patients. After adjusting for confounding factors, the multivariate analysis revealed a 7% decrease in severe impairment of ADL after stroke for every unit (g/L) increase in serum albumin levels. Compared with individuals with lower serum albumin levels (Q1: ≤ 37.4 g/L), the adjusted odds ratios (OR) for severe of ADL impairment among stroke patients in Q2 (37.4–40.21 g/L), Q3 (40.21–42.80 g/L), and Q4 (≥42.8 g/L) were 0.68 (95% CI: 0.4–1.15, p = 0.148), 0.55 (95% CI: 0.32–0.97, p = 0.04), and 0.64 (95% CI: 0.37–1.15, p = 0.139), respectively. The relationship between serum albumin and severe impairment of ADLs in stroke patients showed an L-shaped curve (non-linear, p = 0.002), with an inflection point at 38.0 g/L. The OR for significant impairment of ADLs was 0.680 (95% CI: 0.568–0.814, p < 0.001) in participants with serum albumin levels <38.0 g/L. However, when serum albumin levels were greater than or equal to 38.0 g/L, the severe impairment of ADLs no longer decreased with rising serum albumin levels. Conclusion: In summary, an L-shaped connection with an approximate inflection point of 38.0 g/L was found between blood albumin levels and significant ADL impairment in stroke patients. The results of this study suggest that increasing serum albumin levels can significantly help improve the severity of ADL impairment in stroke patients, particularly those with serum albumin levels below 38.0 g/L. [ABSTRACT FROM AUTHOR]

Quad-polarization synthetic aperture radar (SAR) satellites are important detection tools in Earth observation and remote sensing; in particular, they are of great significance for accurately interpreting radar data and inverting geophysical parameters. Polarimetric calibration is particularly critical to eliminate the effects of distortion in polarized SAR data. The C-SAR/02 satellite launched by China is an important part of the C-band synthetic aperture radar (SAR) constellation, and the quad-polarization strip I (QPSI) is an important imaging mode for its sea–land observation. The relevant research on its polarimetric calibration is still lacking. This study's polarimetric calibration of C-SAR/02 was performed based on the active radar calibrator (ARC) method using four independently developed L/S/C multi-band ARCs and several trihedral corner reflectors (CRs). The polarimetric calibration distortion matrix varies along the range direction; the polarimetric calibration distortion matrix and polarimetric calibration accuracy along the range direction were analyzed, incorporating the devices in different range directions to calculate the distortion matrix. This approach improved the accuracy of the polarimetric calibration results and the effect of the quantization application of the C-SAR satellites. Moreover, our experimental results indicate that the method presented herein is suitable for the C-SAR/02 satellite and may also be more universally applicable to C-SAR-series satellites. [ABSTRACT FROM AUTHOR]

Background: The circadian rhythm of myocardial infarction (MI) in patients with obstructive sleep apnea (OSA) remains disputable and no studies have directly evaluated the relationship between nocturnal hypoxemia and the circadian rhythm of MI. The aim of the current study was to evaluate the association of OSA and nocturnal hypoxemia with MI onset during the night., Methods: Patients with MI in the OSA-acute coronary syndrome (ACS) project (NCT03362385) were recruited. The time of MI onset was identified by patient's report of the chest pain that prompted hospital admission. All patients underwent an overnight sleep study using a type III portable sleep monitoring device after clinical stabilization during hospitalization. The difference in circadian variation of MI onset was evaluated between patients with moderate/severe OSA and non/mild OSA and those with or without nocturnal hypoxemia. Nocturnal hypoxemia was evaluated using 3 variables, including oxygen desaturation index, minimum oxygen saturation, and total sleep time with saturation <90%., Results: Among 713 patients enrolled, 398 (55.8%) had moderate/severe OSA (apnea-hypopnea index ≥15 events·h - 1). Compared with the non/mild OSA group, the MI onset was significantly increased in the moderate/severe OSA group between midnight to 5:59 am in 6-hour epochs analysis (26.9% versus 18.4%, P =0.008). Only in patients with both moderate/severe OSA and nocturnal hypoxemia, including oxygen desaturation index ≥15, minimum oxygen saturation ≤86%, and total sleep time with saturation <90% ≥2%, the incidence of MI onset between midnight to 5:59 am was significantly increased. Moderate/severe OSA (adjusted odds ratio 1.66 [95% CI, 1.13-2.43]; P =0.01) and nocturnal hypoxemia (oxygen desaturation index ≥15 model, adjusted odds ratio 1.80, [95% CI, 1.21-2.66]; minimum oxygen saturation ≤86% model, adjusted odds ratio 1.70 [95% CI, 1.16-2.47]; P =0.006; total sleep time with saturation <90% ≥2% model, adjusted odds ratio 1.54 [95% CI, 1.04-2.27]; P =0.03) significantly predicted MI occurrence from midnight to 6:00 am., Conclusions: A peak of incident MI onset between midnight to 5:59 am was observed in patients with moderate/severe OSA, especially in those presenting with nocturnal hypoxemia.

High-resolution awake mouse functional magnetic resonance imaging (fMRI) remains challenging despite extensive efforts to address motion-induced artifacts and stress. This study introduces an implantable radio frequency (RF) surface coil design that minimizes image distortion caused by the air/tissue interface of mouse brains while simultaneously serving as a headpost for fixation during scanning. Furthermore, this study provides a thorough acclimation method used to accustom animals to the MRI environment minimizing motion-induced artifacts. Using a 14 T scanner, high-resolution fMRI enabled brain-wide functional mapping of visual and vibrissa stimulation at 100 µm×100 µm×200 µm resolution with a 2 s per frame sampling rate. Besides activated ascending visual and vibrissa pathways, robust blood oxygen level-dependent (BOLD) responses were detected in the anterior cingulate cortex upon visual stimulation and spread through the ventral retrosplenial area (VRA) with vibrissa air-puff stimulation, demonstrating higher-order sensory processing in association cortices of awake mice. In particular, the rapid hemodynamic responses in VRA upon vibrissa stimulation showed a strong correlation with the hippocampus, thalamus, and prefrontal cortical areas. Cross-correlation analysis with designated VRA responses revealed early positive BOLD signals at the contralateral barrel cortex (BC) occurring 2 s prior to the air-puff in awake mice with repetitive stimulation, which was not detected using a randomized stimulation paradigm. This early BC activation indicated a learned anticipation through the vibrissa system and association cortices in awake mice under continuous exposure of repetitive air-puff stimulation. This work establishes a high-resolution awake mouse fMRI platform, enabling brain-wide functional mapping of sensory signal processing in higher association cortical areas., Competing Interests: DH, XL, ZX, BZ, SC, XZ, AL, AM, YJ, AD No competing interests declared, XY Cofounder of MRIBOT LLC, (© 2024, Hike, Liu et al.)