Transient potassium current channels (I A channels), which are expressed in most brain areas, have a central role in modulating feedforward and feedback inhibition along the dendroaxonic axis. Loss of the modulatory channels is tightly associated with a number of brain diseases such as Alzheimer’s disease, epilepsy, fragile X syndrome (FXS), Parkinson’s disease, chronic pain, tinnitus, and ataxia. However, the functional significance of I A channels in these diseases has so far been underestimated. In this review, we discuss the distribution and function of I A channels. Particularly, we posit that downregulation of I A channels results in neuronal (mostly dendritic) hyperexcitability accompanied by the imbalanced excitation and inhibition ratio in the brain’s networks, eventually causing the brain diseases. Finally, we propose a potential therapeutic target: the enhanced action of I A channels to counteract Ca 2+ -permeable channels including NMDA receptors could be harnessed to restore dendritic excitability, leading to a balanced neuronal state.

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This study focuses primarily on improving large-scale hydrogen liquefaction process by integrating liquefied natural gas (LNG) stream to utilize LNG cold energy. For the hydrogen liquefaction process, a large amount of energy is required for the compression and the cryogenic refrigeration system. LNG is one of the main sources for producing hydrogen, and it can be an opportunity to save energy because LNG cold energy is normally discarded into seawater during regasification. The objective of this study is to reduce the specific energy consumption and specific liquefaction cost. The proposed design which produces 300 ton/day of liquid hydrogen is compared with a base case design comprising two-stage mixed refrigerant refrigeration cycles. To minimize the specific energy consumption, multiparameter optimization is conducted by connecting simulation results to a genetic algorithm. Through the optimization, the flow rates of LNG and MR in the precooling cycle decrease by 1.08 and 21.00 kg/s, respectively. The specific energy consumption is reduced from 4.36 to 4.07 kWh/kg-LH 2 . Particularly, in the precooling cycle where the LNG stream is integrated, it decreases by more than 26.40%. Regarding the specific liquefaction cost of hydrogen liquefaction, the capital expenses are reduced by 15.16%, and annual operating expenses are diminished by 9.05%. Therefore, the total specific cost liquefaction shows a reduction of approximately 7.7%.Overall, an efficient hydrogen liquefaction process will provide a guideline for LNG-dependent countries by reducing the specific energy consumption and the specific liquefaction cost by recovering the waste cold energy.

Summary This study mainly focuses on determining the optimal configuration that efficiently utilizes liquefied natural gas (LNG) cold energy in hydrogen precooling for liquid hydrogen production. To achieve this goal, two different configurations are designed: (a) adding LNG cold energy to the existing hydrogen precooling cycle and (b) replacing the existing hydrogen precooling cycle with LNG cold energy. An equilibrium hydrogen model is developed to reflect the thermodynamic property of ortho‐para conversion of hydrogen. Bayesian optimization is performed to determine the optimal operating conditions which minimize the specific energy consumption for all configurations. The specific energy consumption of the configuration involving hydrogen precooling with only LNG is 5.613 kWh/kg‐LH2, and it is reduced by 8.13% and 3.19% from the base case design and the configuration involving hydrogen precooling with both LNG and a mixed refrigerant cycle, respectively. In addition, a techno‐economic analysis is conducted. Compare to the base case design, the capital cost and operating cost of the design replacing hydrogen precooling with LNG are reduced by 31.76% and 11.55%, respectively. This study shows that the proposed design of replacing the hydrogen precooling cycle with an LNG stream can save energy consumption, moreover, it is highly effective for capital investment saving due to its simple configuration.