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Iron load is closely associated with the initiation and progression of Alzheimer's disease (AD) . Although age-dependent deposition of β-amyloid (A β) in senile plaques (SPs) , and neurofibrillary tangles (NFTs) formed by accumulation of hyperphosphorylated tau proteins are two major pathological features of AD, there are still many different views on the inducing factors of SPs and NFTs. We reviewed the new developments in the relationship between imbalance of brain iron homeostasis and the pathogenesis of AD, with a summary presented as follows: (1) Age-related iron deposits in different brain regions may damage normal cognitive function and behavior. (2) Iron imbalance and oxidative stress may together or independently promote Aβ overproduction by activating β- or γ-secretases and inhibiting α-secretase, and also cause tau hyperphosphorylation by activating protein kinases, such as glycogen synthase kinase-3β, cyclin-dependent protein kinase-5, and inhibiting protein phosphatase 2A. Iron imbalance-induced changes will in turn aggravate brain iron deposition and distribution. The vicious circle between iron imbalance and Aβ/tau anomalies may eventually lead to AD. (3) Iron overload may also directly or indirectly injure organelles, causing endoplasmic reticulum stress, mitochondrial and autophagy dysfunction, and damaging synaptic function via inducing or aggravating the aggregation or accumulation of A βand tau. At the same time, hydroxyl radicals produced via the Fenton reaction associated with abnormal iron metabolism, may trigger oxidative stress, destroy the structure and function of cell lipids, protein and DNA, eventually leading to cell death. (4) Given the limitations and side effects of long-term application of traditional iron chelators, alpha-lipoic acid and lactoferrin as self-synthesized naturally small molecules, are expected to be applied to clinical practice, for they have shown very intriguing biological activities in blocking Aβ-aggregation, tau hyperphosphorylation and neuronal damage. We believe that iron-targeted therapies are a promising direction for the treatment of AD.

This study addresses the ongoing demand for increased efficiency and reduced emissions in turbomachinery combustion systems. A custom-built high-pressure combustor was designed and manufactured at the Low Carbon Combustion Centre (LCCC) of the University of Sheffield to investigate the impact of different aromatic hydrocarbons on emission rates. The research involved the comprehensive testing of Jet−A1 fuel and six aromatic species blends under high-pressure conditions of 10 bar. Based on the numerical CFD simulations by ANSYS 19.2, tangential dual air injection and a strategically placed V-shaped baffle plate were utilised to enhance fuel-air mixing and combustion stability. Experimental results demonstrated a negative correlation between combustion temperature and particulate matter (PM) emissions, with higher temperatures yielding lower PM emissions. Unburned hydrocarbons (UHCs), nitrogen oxides ( N O x ), carbon monoxide ( C O ), and carbon dioxide ( C O 2 ) emissions were also analysed. Ethylbenzene produced the highest UHC and C O emissions, while Indane exhibited the lowest levels of these pollutants, suggesting more complete combustion. O−xylene generated the highest N O x emissions, correlating with its higher combustion temperatures. This research enhances our understanding of gas turbine combustor design and the combustion behaviour of aromatic species, providing valuable insights for developing low-emission, high-efficiency gas turbine combustion technologies. [ABSTRACT FROM AUTHOR]

In this study, pollution level, distribution, toxicity, molecular composition, probable sources as well as health risks of polycyclic aromatic hydrocarbons (PAHs) in urban and industrial soils of Kerman metropolis were investigated. Kerman is a fast-growing city and a fine example of an arid city in a developing country. For this purpose, concentrations of 16 individual PAHs in 30 samples taken from the city soils and its industrial zones were determined by gas chromatography/mass spectrometry. The ∑PAHs concentration in urban soil samples varied from 26.1 to 902.8 μg/kg, with the mean and median of 302.6 and 148.4 µg/kg, respectively. In comparison, ∑PAHs in industrial soils ranged from 26.8to 251.9 μg/kg, with the mean and median values of 65.9 and 42.9 µg/kg, respectively. Four-ring PAHs comprise the dominant compounds in urban soils, whereas, two- and three-ring PAHs proved to be the most abundant compounds in industrial soils. Source apportionment was conducted using ring classification, diagnostic ratios, PCA, and multilinear regression (MLR). Also, human health risk assessment was undertaken through employing US EPA standard statistical models. This survey revealed that PAH pollution in urban soils originates mainly from fossil fuel combustion and in industrial soils from petrogenic sources. On the whole, in the Kerman environment, the shares of petroleum combustion, natural gas combustion, and petrogenic sources were 45.32%, 34%, and 20.68% respectively. Based on this study, the ecological risk of PAHs was low-to-moderate, and incremental lifetime cancer risk for children and adults were 1.35 × 10−4 and 1.04 × 10−4 respectively, indicating rather high risks. [ABSTRACT FROM AUTHOR]

Numerous research papers on biosorption have been published in the past four decades. This paper reviews and compares heavy metal uptake capacities of various biological and non-biological materials. Adsorption mechanisms and processes of heavy metal ions (HMIs) onto biomasses are summarised and discussed, respectively. In general, all types of adsorbents exhibit certain uptake capacities for HMIs, but the capacity values for different types of biomasses and non-biological materials vary significantly. For HMIs, the reported values for bacterial biomasses typically range from 0.06 mmol·g−1 to 2.84 mmol·g−1; for fungi and yeasts, 0.03 mmol·g−1 to 2.44 mmol·g−1; for fresh water algae, 0.02 mmol·g−1 to 3.15 mmol·g−1; for marine algae, 0.23 mmol·g−1 to 3.77 mmol·g−1; for other biological materials/derivatives, 0.01 mmol·g−1 to 1.78 mmol·g−1 and for non-biological materials, 0.003 mmol·g−1 to 2.40 mmol·g−1. Thereinto, a few macroalgal species exhibit much higher adsorption capacities for HMIs relative to other types of adsorbents. Statistical analysis of heavy metal uptake capacities of various biological and non-biological materials indicates that marine algae are most suitable for the development of industrial biosorbents for the remediation of diluted HMIs-bearing effluents. Biosorption mechanisms of HMIs by biomasses include physical adsorption, ion exchange, electrostatic interaction, surface complexation and inorganic microprecipitation. the physicochemical properties of biosorbents and HMIs as well as external adsorption conditions significantly influence the adsorption process of HMIs onto biomasses. It could be concluded from numerous previous studies that pseudo-first-order and pseudo-second-order models are the most commonly utilised to characterise adsorption process. Up to date biosorption of HMIs remains largely in the laboratory stage. Combining microscopic mechanisms with macroscopic models may be one of the future research directions for removal of HMIs by biomasses. [ABSTRACT FROM AUTHOR]

Transition metals and organic ligands combine to form metal‐organic frameworks (MOFs), which possess distinct active sites, large specific surface areas and stable porous structures, giving them considerable promise for CO2 reduction electrocatalysis. In the present study, using spin polarisation density‐functional theory, a series of 2D MOFs constructed from 3d transition metal and hexamethylene dipyrazoline quinoxaline(HADQ) were investigated. The calculated binding energies between HADQ and metal atoms for the ten TM‐HADQ monolayers were strong sufficient to stably disperse the metal atoms in the HADQ monolayers. Of the ten catalysts tested, seven (Sc, Ni, Cu, Zn, Ti, V and Cr) exhibited high CO2 reduction selectivity, while Mn, Fe and Co required pH values above 2.350, 6.461 and 6.363, respectively, to exhibit CO2 reduction selectivity. HCOOH was the most important producer for Sc, Zn, Ni and Mn, while CH4 was the main producer for Ti, Cr, Fe and V. Cu and Co were less selective, producing HCHO, CH3OH, and CH4 simultaneously at the same rate‐determining step and limiting potential. The Cu‐HADQ catalyst had a high overpotential for the HCHO product (1.022 V), while the other catalysts had lower overpotentials between 0.016 V and 0.792 V. Thus, these results predict TM‐HADQ to show excellent activity in CO2 electrocatalytic reduction and to become a promising electrocatalyst for CO2 reduction. [ABSTRACT FROM AUTHOR]

The fatigue test of wind turbine blade is an important means to verify the fatigue life of wind turbine blade. This paper analyses the problems existing in the fatigue test of wind turbine blade, focuses on the excitation mode, the relationship between excitation amplitude and vibration frequency and the vibration principle, and puts forward feasible solutions in practical operation.