The rate of sorption of -butane on the structurally flexible metal-organic framework [Cu(H-Me-trz-ia)], including its complete structural transition between a narrow-pore phase and a large-pore phase, was studied by sorption gravimetry, IR spectroscopy, and powder X-ray diffraction at close to ambient temperature (283, 298, and 313 K). The uptake curves reveal complex interactions of adsorption on the outer surface of MOF particles, structural transition, of which the overall rate depends on several factors, including pressure step, temperature, as well as particle size, and the subsequent diffusion into newly opened pores. With the aid of a kinetic model based on the linear driving force (LDF) approach, both rates of diffusion and structural transition were studied independently of each other. It is shown that temperature and applied pressure steps have a strong effect on the rate of structural transition and thus, the overall velocity of gas uptake. For pressure steps close to the upper boundary of the gate-opening, the rate of structural transition is drastically reduced. This feature enables a fine-tuning of the overall velocity of sorption, which can even turn into anti-Arrhenius behavior.
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http://dx.doi.org/10.3390/nano13030601 | DOI Listing |
BMC Public Health
January 2025
Faculty of Science of Semlalia, Department of Biology, Cadi Ayyad University, Marrakesh, Morocco.
Low- and middle-income countries are facing a rapid increase in nutritional problems, particularly in Africa, where undernutrition, overweight and micronutrient deficiencies coexist, creating a double burden of malnutrition and a challenge to public health policies. In this context, Morocco stands out for its early nutritional transition, characterized by a moderate prevalence of overweight and undernutrition and elevated levels of micronutrient deficiencies. The aim of this study was to assess the weight status of women of childbearing age and identify its determinants to suggest ways to improve it.
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January 2025
The Hormel Institute, University of Minnesota, Austin, MN, 55912, USA.
ABCB1 is a broad-spectrum efflux pump central to cellular drug handling and multidrug resistance in humans. However, how it is able to recognize and transport a wide range of diverse substrates remains poorly understood. Here we present cryo-EM structures of lipid-embedded human ABCB1 in conformationally distinct apo-, substrate-bound, inhibitor-bound, and nucleotide-trapped states at 3.
View Article and Find Full Text PDFNat Mater
January 2025
State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures (MOE), and Department of Physics, Fudan University, Shanghai, China.
Polymorphism, commonly denoting diverse molecular or crystal structures, is crucial in the natural sciences. In van der Waals antiferromagnets, a new type of magnetic polymorphism arises, presenting multiple layer-selective magnetic structures with identical total magnetization. However, resolving and manipulating such magnetic polymorphs remain challenging.
View Article and Find Full Text PDFLuminescence
January 2025
Department of Chemistry, Faculty of Science, Damanhour University, Damanhour, Egypt.
Herein, a novel spectrofluorometric sensor is proposed for the sensitive analysis of two nonfluorescent mucolytic drugs, namely, acetylcysteine (ACT) and carbocisteine (CST), utilizing the newly synthesized 2-[(2-hydroxyethyl)-(2,8,10-trimethylpyrido[2',3':3,4]pyrazolo[1,5-a]pyrimidin-4-yl)-amino]-ethanol as a fluorescence probe (Flu. Probe). This fluorophore exhibits fluorescence emission at 445 nm upon excitation at 275 nm.
View Article and Find Full Text PDFActa Biomater
January 2025
Key Laboratory of Endocrine Glucose & Lipids Metabolism and Brain Aging, Ministry of Education; Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, 250021, China; Shandong Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, Shandong, 250021, China; Shandong Engineering Laboratory of Prevention and Control for Endocrine and Metabolic Diseases, Jinan, Shandong, 250021, China. Electronic address:
Nonalcoholic fatty liver disease (NAFLD) is a metabolic liver disorder with severe complications. Mitochondrial dysfunction due to over-opening of the mitochondrial permeability transition pore (mPTP) in liver cells plays a central role in the development and progression of NAFLD. Restoring mitochondrial function is a promising strategy for NAFLD therapy.
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