Porous Material (Titanium Gas Diffusion Layer) in Proton Exchange Membrane Fuel Cell/Electrolyzer: Fabrication Methods & GeoDict: A Critical Review.

Proton exchange membrane fuel cell (PEMFC) is a renewable energy source rapidly approaching commercial viability. The performance is significantly affected by the transfer of fluid, charges, and heat; gas diffusion layer (GDL) is primarily concerned with the consistent transfer of these components, which are heavily influenced by the material and design. High-efficiency GDL must have excellent thermal conductivity, electrical conductivity, permeability, corrosion resistance, and high mechanical characteristics. The first step in creating a high-performance GDL is selecting the appropriate material. Therefore, titanium is a suitable substitute for steel or carbon due to its high strength-to-weight and superior corrosion resistance. The second crucial parameter is the fabrication method that governs all the properties. This review seeks to comprehend numerous fabrication methods such as tape casting, 3D printing, freeze casting, phase separation technique, and lithography, along with the porosity controller in each process such as partial sintering, input design, ice structure, pore agent, etching time, and mask width. Moreover, other GDL properties are being studied, including microstructure and morphology. In the future, GeoDict simulation is highly recommended for optimizing various GDL properties, as it is frequently used for other porous materials. The approach can save time and energy compared to intensive experimental work.

Experimental and Computational Study of Optimized Gas Diffusion Layer for Polymer Electrolyte Membrane Electrolyzer.

Polymer electrolyte membrane fuel cells (PEMFCs) and PEM electrolyzer are emerging technologies that produce energy with zero carbon emissions. However, the commercial feasibility of these technologies mostly relies on their efficiency, which is determined by individual parts, including the gas diffusion layer (GDL). GDL transfers fluid and charges while protecting other components form flooding and corrosion. As there is a very limited attention toward the simulation work, in this work, a novel approach was utilized that combines simulation and experimental techniques to optimize the sintering temperature of GDL. Ti64 GDL was produced through tape casting, a commercial method famous for producing precise thickness, uniform, and high-quality films and parameters such as slurry composition and rheology, casting parameters, drying, and debinding were optimized. The porosity and mechanical properties of the samples were tested experimentally at various sintering temperatures. The experimental results were compared with the simulated results achieved from the GeoDict simulation tool, showing around 96% accuracy, indicating that employing GeoDict to optimize the properties of Ti64 GDL produced via tape casting is a critical step towards the commercial feasibility of PEMFCs and electrolyzer. These findings significantly contribute to the development of sustainable energy solutions.

Binder-free cupric-ion containing zinc sulfide nanoplates-like structure for flexible energy storage devices.

Researchers have been enthusiastic about developing high-performance electrode materials based on metal chalcogenides for energy storage applications. Herein, we developed cupric ion-containing zinc sulfide (ZnS:Cu) nanoplates by using a solvothermal approach. The as-synthesized ZnS:Cu nanoplates electrode was characterized and analyzed by using XRD, SEM, TEM, EDS, and XPS. The binder-free flexible ZnS:Cu nanoplates exhibited excellent specific capacitance of 545 F g-1 at a current density of 1 A g-1. The CV and GCD measurements revealed that the specific capacitance was mainly attributed to the Faradaic redox mechanism. Further, the binder-free flexible ZnS:Cu nanoplates electrode retained 87.4% along with excellent Coulombic efficiency (99%) after 5000 cycles. The binder-free flexible ZnS:Cu nanoplates exhibited excellent conductivity, specific capacitance, and stability which are beneficial in energy storage systems. These findings will also open new horizons amongst material scientists toward the new direction of electrode development.

Prevalence of Human Papilloma Virus Sub Genotypes following Head and Neck Squamous Cell Carcinomas in Asian Continent, A Systematic Review Article.

OBJECTIVES: In current era of blue brain intelligence and technology access at ease, standardization of disease etiology demands extensive research to drop-down human papilloma virus associated head and neck squamous cell carcinomas impact at large. Present retrospection aims to estimate comparative association of human papilloma virus sub-genotypes in head and neck squamous cell carcinomas, critical analysis of existing research gap, treatment progress, co-infection, gender association, national status and challenges following Human papilloma virus led head and neck squamous cell carcinomas among world largest continent. BACKGROUND: Head and neck squamous cell carcinomas are not just like malignancies of uterine cervix, lymph nodes and breast cancers. Human papilloma virus led head and neck squamous cell carcinomas treatment directly impact Central nervous system in humans. Intriguingly, human papilloma virus mediated immune response increases patient survival, which indirectly transmit human papilloma virus in future generations and act as a potential threat developing neurogenic disorders. METHODS: An objective based search strategy, following comprehensive and specific search approaches were made to retrieve recent 12 years research data from five different NCBI databases. Out of 300 shortlisted articles, only 24 principal studies met the inclusion criteria. RESULTS: Highest human papilloma virus prevalence (10.42 %) was found in South Asia, 5.8 % in South East Asia, 5.7 % East Asia, 2.5% in west Asia and no relevant updated data was found from central Asian continent. Highest prevalence (10%) of HPV genotype-16 was recorded in Asia among 3, 710 enrolled cases including 2201 males, 1149 females and 360 cases of unknown gender. While undifferentiated multiple HPV genotype prevalence was 5.5 % (204 cases). Lowest percentage of HPV sub-types 68, 72, 57, 39 were recorded respectively. Pakistan ranked top reporting highest number of HPV-16 cases, Taiwan HPV-18, India HPV-31, Japan HPV-35 and Singapore in HPV-16 and HPV-18 co-infection rates respectively. CONCLUSIONS: Exact prevalence of HPV associated head and neck squamous cell carcinomas among Asian population is still debatable. Due to higher heterogeneity (P< 0.00001), I2 = 81-88% at 95 % confidence interval), non-availability and limitations of reported studies from Asian sub-continents especially central Asia, western Asia and from south and south east Asia demand large scale collaborative research culture to standardize head and neck squamous cell carcinomas aetiology.
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Licochalcone A from licorice root, an inhibitor of human hepatoma cell growth via induction of cell apoptosis and cell cycle arrest.

We investigated the anti-cancer activity of Licochalcone A (LCA), extracted from licorice root. LCA inhibited the proliferation of HepG2 cells with IC50 (65.96 µM) for 24 h and IC50 (44.13 µM) for 48 h and caused significant morphological changes and also led to intracellular ROS generation. LCA affected HepG2 cell growth by terminating cell cycle development at G2/M transition and further induced the apoptosis process. The mRNA expression of genes involved in cell cycles such as Survivin, Cyclin B1, and CDK1 were reduced; while, Weel, P21, Cyclin D1, and JNK1 showed increased mRNA expression. Two pathways consisting of internal and external factors were responsible for LCA -induced apoptosis. The anti-cancer action involved increased mRNA expression of DR3, DR5, caspases-3, caspases-8, caspases-10, Fas, Bad, Bax, Bcl-2, Bak, and PUMA; besides, decreased level of PKCε, p70S6K, and Akt. This study provides mechanistic explanation for anti-cancer activity of LCA and also suggests its potential role in the treatment of hepatoma cancer.

Molecular mechanism and inhibitory targets of dioscin in HepG2 cells.

Dioscin has been known for its anti-cancer activity; however, its detailed molecular mechanisms have not been studied so far. Herein, we evaluated the anti-cancer activity of dioscin for proliferation inhibition and apoptosis in HepG2 cancer cells. Initially, dioscin was purified and identified from Polygonatum sibiricum by HPLC, MS, and NMR analysis, respectively. Dioscin inhibited the cell multiplication at IC50 of 8.34 µM, altered the cell morphology, arrested the cell cycle in G2/M phase and led to considerable programmed cell death. Furthermore, it has efficiently promoted the mitochondrial pathway and death receptor pathway. The inhibition of Caspase-8 and Caspase-9 proteins in these pathways abolished the dioscin induced apoptosis significantly; while dioscin inhibited the PI3K/Akt/mTOR pathway. Moreover, dioscin exposure led to enhanced intracellular ROS generation and the mRNA expression of JNK gene which emphasized their involvement in the apoptosis process in HepG2 cells.