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In order to study the effect of supercritical carbon dioxide (ScCO2) on the mechanical properties of granite located in and near the core of the CO2-based enhanced geothermal system (EGS) region, fluid–rock interaction experiments were conducted at 210, 240 and 270 ℃. Three test conditions were used: (1) ScCO2 and dry granite; (2) ScCO2, water vapor and granite; and (3) ScCO2 and granite soaked in water for 24 h. The P-wave velocity, uniaxial compressive strength (UCS), and Young’s modulus of all ScCO2- treated granite samples and one untreated granite sample were obtained by carrying out the wave velocity tests and uniaxial compression tests. The wave velocity tests showed that the P-wave velocities of all ScCO2-treated granite samples were reduced compared to that of the untreated sample. The uniaxial compression test showed that the UCS and Young’s modulus were almost not affected. From the failure mode, it can be seen that the untreated granite more likely presented the brittle tensile failure, while the treated sample showed more likely shear failure. As the temperature increased, the failure mode became more and more close to shear failure. Experimental results showed that the ScCO2 induced slight damage to the granite under dry or a little water condition, causing a slight decrease in the brittleness, and a small increase in the plasticity. The P-wave velocity decreased slightly and the impact on the granite strength can be negligible. Therefore, the interaction of CO2–rock will not cause obvious effect on the mechanical properties of granite located in and near the core of the CO2–EGS region.

In this article, we designed and synthesized two novel swallow-tailed liquid crystal monomers (M1 and M2) with different chain lengths and rigidities centered on 3,4,5-trihydroxybenzoic acid and two series of side-chain liquid crystals polymers PN1 and PN2. All liquid crystal monomers and polymers were conformed to the molecular designs by FT-IR and NMR. The liquid crystal properties were tested by DSC and POM, and the results showed that M1 and M2 were thermotropic enantiotropic nematic liquid crystals and the side-chain liquid crystal polymers PN1 and PN2 series were typical amorphous liquid crystal polymers. With the increase of monomer content, the glass transition temperatures and clearing points of PN1 and PN2 series enhanced. With the increase of the number of mesogens in the liquid crystal monomer, the rigidity was enhanced, and the liquid crystal performance of the polymer was better. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation (ECMO) is a vital emergency procedure providing respiratory and circulatory support to critically ill patients, especially those with compromised cardiopulmonary function. Its use has grown due to technological advances and clinical demand. Prolonged ECMO usage can lead to complications, necessitating the timely assessment of peripheral microcirculation for an accurate physiological evaluation. This study utilizes non-invasive near-infrared spectroscopy (NIRS) to monitor knee-level microcirculation in ECMO patients. After processing oxygenation data, machine learning distinguishes high and low disease severity in the veno-venous (VV-ECMO) and veno-arterial (VA-ECMO) groups, with two clinical parameters enhancing the model performance. Both ECMO modes show promise in the clinical severity diagnosis. The research further explores statistical correlations between the oxygenation data and disease severity in diverse physiological conditions, revealing moderate correlations with the acute physiologic and chronic health evaluation (APACHE II) scores in the VV-ECMO and VA-ECMO groups. NIRS holds the potential for assessing patient condition improvements. [ABSTRACT FROM AUTHOR]

Patients with mild cognitive impairment (MCI) are at a high risk of developing future dementia. However, early identification and active intervention could potentially reduce its morbidity and the incidence of dementia. Functional near‐infrared spectroscopy (fNIRS) has been proposed as a noninvasive modality for detecting oxygenation changes in the time‐varying hemodynamics of the prefrontal cortex. This study sought to provide an effective method for detecting patients with MCI using fNIRS and the Wisconsin card sorting test (WCST) to evaluate changes in blood oxygenation. The results revealed that all groups with a lower mini‐mental state examination grade had a higher increase in HHb concentration during a modified WCST (MCST). The increase in the change in oxygenated hemoglobin concentration in the stroke group was smaller than that in the normal group due to weak cerebrovascular reactivity. [ABSTRACT FROM AUTHOR]