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Purpose:To investigate differences in sensitivity to myopia-inducing stimuli of two strains of pigmented guinea pigs. Methods:Eleven-day-old animals (New Zealand [NZ], n = 24 and Elm Hill strains [EH], n = 26) wore either a +2 or -2 diopter (D) lens over one eye and a plano lens over the fellow eye for 5 days; other 10-day-old EH (n = 9) and 7-day-old NZ (n = 9) animals were monocularly form-deprived (FD) for 28 days. Choroidal thickness and axial length were measured using A-scan ultrasonography at baseline and after 1 and 5 days for optical defocus treatments, and at baseline and after 28 days for the FD treatment. Refractive errors were measured by retinoscopy. Choroids of untreated animals were also evaluated using spectral-domain optical coherence tomography. Results:One day of optical defocus induced bidirectional (optical sign-dependent) choroidal responses in EH animals only (P < 0.01). Similar responses were detected in NZ animals after 5 days (P < 0.01), with concordant spherical equivalent refraction changes (P < 0.01). Compared with NZ animals, EH animals developed minimal myopia with FD after 28 days (-4.58 ± 0.97 vs. -0.69 ± 0.75 D for NZ versus EH, P < 0.001). Yet, EH animals showed paradoxical choroidal thickening, 20 ± 9 vs. -8 ± 8 μm for EH versus NZ, P < 0.001. Untreated EH animals also had significantly thicker choroids than NZ animals (147 ± 19 vs. 132 ± 16 μm, P < 0.05), with well-defined layering. Conclusions:As previously reported in chicks, guinea pigs show strain-related differences in response to myopia-inducing stimuli. The finding of a thicker, multilayered choroid in the strain showing decreased sensitivity to FD is provocative, suggesting a possible protective role of the choroid.

The proton exchange membrane electrolysis cell (PEMEC) has attracted considerable attention for large-scale and efficient hydrogen production because of its high current density, high hydrogen purity and fast dynamic response. Flow field distributions and water and thermal management characteristics of a PEMEC are vital for electrolytic cell structure and the determination of operating condition. A three-dimensional, non-isothermal, electrochemical model of a PEMEC was established in this manuscript. The flow field distribution and water and thermal management of the PEMEC are discussed. The corresponding results showed that the pressure of the flow channel decreased diagonally from the inlet to the outlet, and the pressure and velocity distribution exhibited a downward opening shape of a parabola. At the same inlet flow rate, when the voltage was 1.6 V, the oxygen generation rate was 15.74 mol/(cm2·s), and when the voltage was 2.2 V, the oxygen generation rate was 332.05 mol/(cm2·s); due to the change in the oxygen production rate, the pressure difference at 2.2 V was 2.5 times than that at 1.6 V. When the stoichiometric number was less than two, the average temperature of the catalyst layer (CL) decreased rapidly with the increase in the water flow rate. When the voltage decreased to 2.1 V, the current density came to the highest value when the stoichiometric number was 0.7, then the current density decreased with an increase in the stoichiometric number. When stoichiometric numbers were higher than five, the surface temperature and current density remained basically stable with the increase in the water flow rate, and the water and thermal management and electrolysis characteristics performed better. The research results could optimize the water supply of electrolysis cells. According to the velocity distribution law of the flow field, the water and thermal management performance of the PEMEC could be estimated, further promoting safety and reliability. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) remains a major threat to human health due to the limited energy supply, disordered cell metabolism, massive cardiomyocyte death, and restricted regeneration. Although currently available therapies may relieve myocardial damage, restoring the dysregulated energy metabolism to normal levels has not yet been achieved. MOTS‐c has recently been identified as a regulator of biological metabolism to combat aging; however, its role in reprogramming cardiac metabolism remains to be elucidated. Here, MOTS‐c is chemically conjugated to self‐assembling Q11 peptide to fabricate an injectable hydrogel (MQgel) aimed to improve mitochondria function and cardiomyocyte metabolism post‐MI. It is observed that MQgel effectively protects mitochondria from oxidative damage and normalized cardiomyocyte metabolism, including glucose uptake, glycolysis, and the tricarboxylic acid (TCA) cycle, thereby inhibiting cardiomyocyte death and enhancing cardiomyocyte activity. In a rat MI model, intramyocardial injection of MQgel successfully minimizes the infarct area and fibrosis, promotes angiogenesis, suppresses myocardial hypertrophy, and improves cardiomyocyte survival and metabolic enzyme activity, all of which collaboratively attenuate the maladaptive cardiac remodeling and boost cardiac function and tissue repair. The findings suggest that the self‐assembled mitochondria metabolism‐regulatory peptide hydrogel effectively treats MI, and cellular bioenergy modulation provides a new therapeutic approach for tissue repair after injury. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are experiencing explosive developments due to their advantages in energy conservation and environmental protection. As a pivotal component of EVs, the safety performance of lithium-ion batteries directly affects driving miles and even safety; hence, a battery thermal management system (BTMS) is especially important. To improve the thermal safety performance of power battery modules, first, a new leak-proof phase change material (PCM)-coupled liquid-cooled composite BTMS for large-scale battery modules is proposed in this research. Second, the numerical simulation analysis method was utilized to analyze the influences of the fluid flow channel shape, working fluid inlet temperature, inlet velocity, and reverse flow conditions on the BTMS. Eventually, the abovementioned performances were compared with the traditional PCM-coupled liquid-cooling strategy. The relative data indicated that the Tmax was reduced by 17.5% and the ΔTmax was decreased by 19.5% compared to the liquid-cooling approach. Further, compared with conventionally designed PCM composite liquid cooling, the ΔTmax was reduced by 34.9%. The corresponding data showed that, when using the e-type flow channel, reverse flow II, the inlet flow velocity was 0.001–0.005 m/s, and the inlet temperature was the ambient temperature of the working condition. The thermal performance of the anti-leakage system with a thermal conduction slot PCM-coupled liquid-cooling composite BTMS reached optimal thermal performance. The outcome proved the superiority of the proposed BTMS regarding temperature control and temperature equalization capabilities. It also further reduced the demand for liquid-cooling components, avoided the problem of the easy leakage of the PCM, and decreased energy consumption. [ABSTRACT FROM AUTHOR]