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881.
Picosecond time-resolves spin relaxation kinetics of high-density free carriers is investigated at low temperatures on CdSe (x =0) and in the dilute semimagnetic semiconductor Cd1-xMnx Se for x =0.05 and 0.10. The fast spins relaxation observed in CdSe results from a mechanism associated with the noncentrosymmetric character of the band structure for this material. This process is similar to the one proposed by M.I. D'yakonov and V.I. Perel' (1971) for the zinc blende crystal structures. The spin relaxation times in CdSe are on the order of 30 ps. The spin relaxation time are <20 ps in semimagnetic semiconductor Cd1-xMnSe and are consistent with spin-flip Raman scattering measurements. The increase in spin relaxation rate relative to CdSe is explained in terms of the carrier spin exchange between the carriers and the magnetic spin sites. A probable cause for the reduction in the observed spin polarization factor for carriers in Cd1-xMnxSe ( x ≠0) is presented 相似文献
882.
Alfano R. Tata D. Cordero J. Tomashefsky P. Longo F. Alfano M. 《Quantum Electronics, IEEE Journal of》1984,20(12):1507-1511
The visible fluorescence spectra have been measured from cancerous and normal rat kidney and prostate tissues, and from cancerous rat and mouse bladder tissues. The spectral profiles from the cancerous and normal tissues are substantially different; showing characteristic principal and secondary maxima. These peaks are assigned to fluorphors such as flavins and porphyrins in different environments in the two types of cell media. 相似文献
883.
In spatial cognition studies several cognitive factors were analysed in order to identify the aspect that could constitute the basis for the capacity of organising spatial knowledge into survey maps. 相似文献
884.
Giorgia Dinoi Michael Morin Elena Conte Hagar Mor Shaked Maria Antonietta Coppola Maria Cristina DAdamo Orly Elpeleg Antonella Liantonio Inbar Hartmann Annamaria De Luca Rikard Blunck Angelo Russo Paola Imbrici 《International journal of molecular sciences》2022,23(15)
Mutations in the KCNA1 gene, encoding the voltage-gated potassium channel Kv1.1, have been associated with a spectrum of neurological phenotypes, including episodic ataxia type 1 and developmental and epileptic encephalopathy. We have recently identified a de novo variant in KCNA1 in the highly conserved Pro-Val-Pro motif within the pore of the Kv1.1 channel in a girl affected by early onset epilepsy, ataxia and developmental delay. Other mutations causing severe epilepsy are located in Kv1.1 pore domain. The patient was initially treated with a combination of antiepileptic drugs with limited benefit. Finally, seizures and ataxia control were achieved with lacosamide and acetazolamide. The aim of this study was to functionally characterize Kv1.1 mutant channel to provide a genotype–phenotype correlation and discuss therapeutic options for KCNA1-related epilepsy. To this aim, we transfected HEK 293 cells with Kv1.1 or P403A cDNAs and recorded potassium currents through whole-cell patch-clamp. P403A channels showed smaller potassium currents, voltage-dependent activation shifted by +30 mV towards positive potentials and slower kinetics of activation compared with Kv1.1 wild-type. Heteromeric Kv1.1+P403A channels, resembling the condition of the heterozygous patient, confirmed a loss-of-function biophysical phenotype. Overall, the functional characterization of P403A channels correlates with the clinical symptoms of the patient and supports the observation that mutations associated with severe epileptic phenotype cluster in a highly conserved stretch of residues in Kv1.1 pore domain. This study also strengthens the beneficial effect of acetazolamide and sodium channel blockers in KCNA1 channelopathies. 相似文献
885.
Seyedeh Fatemeh Mirpoor Concetta Valeria L. Giosafatto Loredana Mariniello Antonella DAgostino Maria DAgostino Marcella Cammarota Chiara Schiraldi Raffaele Porta 《International journal of molecular sciences》2022,23(15)
Various different agri-food biomasses might be turned into renewable sources for producing biodegradable and edible plastics, potentially attractive for food, agricultural and cosmeceutical sectors. In this regard, different seeds utilized for edible and non-edible oil extraction give rise to high amounts of organic by-products, known as seed oil cakes (SOCs), potentially able to become protein-rich resources useful for the manufacturing of biodegradable films. This study reports the potential of SOC derived from Argania spinosa (argan), a well-known plant containing valuable non-refined oil suitable for food or cosmetic use, to be a promising valuable source for production of a protein-based matrix of biomaterials to be used in the pharmaco-cosmetic sector. Thus, glycerol-plasticized films were prepared by casting and drying using different amounts of argan seed protein concentrate, in the presence of increasing glycerol concentrations, and characterized for their morphological, mechanical, barrier, and hydrophilicity properties. In addition, their antioxidant activity and effects on cell viability and wound healing were investigated. The hydrophobic nature of the argan protein-based films, and their satisfying physicochemical and biological properties, suggest a biorefinery approach for the recycling of argan SOC as valuable raw material for manufacturing new products to be used in the cosmeceutical and food industries. 相似文献
886.
Giuliana Pollaci Gemma Gorla Antonella Potenza Tatiana Carrozzini Isabella Canavero Anna Bersano Laura Gatti 《International journal of molecular sciences》2022,23(9)
Ring Finger Protein 213 (RNF213), also known as Mysterin, is the major susceptibility factor for Moyamoya Arteriopathy (MA), a progressive cerebrovascular disorder that often leads to brain stroke in adults and children. Although several rare RNF213 polymorphisms have been reported, no major susceptibility variant has been identified to date in Caucasian patients, thus frustrating the attempts to identify putative therapeutic targets for MA treatment. For these reasons, the investigation of novel biochemical functions, substrates and unknown partners of RNF213 will help to unravel the pathogenic mechanisms of MA and will facilitate variant interpretations in a diagnostic context in the future. The aim of the present review is to discuss novel perspectives regarding emerging RNF213 roles in light of recent literature updates and dissect their relevance for understanding MA and for the design of future research studies. Since its identification, RNF213 involvement in angiogenesis and vasculogenesis has strengthened, together with its role in inflammatory signals and proliferation pathways. Most recent studies have been increasingly focused on its relevance in antimicrobial activity and lipid metabolism, highlighting new intriguing perspectives. The last area could suggest the main role of RNF213 in the proteasome pathway, thus reinforcing the hypotheses already previously formulated that depict the protein as an important regulator of the stability of client proteins involved in angiogenesis. We believe that the novel evidence reviewed here may contribute to untangling the complex and still obscure pathogenesis of MA that is reflected in the lack of therapies able to slow down or halt disease progression and severity. 相似文献
887.
888.
889.
Francesco Caponio Carmine Summo Debora Delcuratolo Antonella Pasqualone 《Journal of the science of food and agriculture》2006,86(3):356-361
Although not perceived as fatty foods by consumers, biscuits contain a consistent quantity of lipids. Since they are daily present in the diet, an experimental study was carried out with the aim of evaluating the quality of the lipid fraction of biscuits. Amounts of fat ranging from 75 to 231 g kg?1, mainly constituted by refined vegetable oils and margarine, were present. A high variability in fatty acid composition was found and in some cases high amounts of trans isomers of unsaturated fatty acid were observed. In addition, HPSEC analysis of polar compounds indicated an extensive hydrolytic degradation of triacylglycerols and also a high level of oxidative degradation. The latter, demonstrated by means of the contemporary measure of oxidised triacylglycerols and of triacylglycerol oligopolymers, was comparable to that found in hydrogenated oils and fats. Copyright © 2005 Society of Chemical Industry 相似文献
890.
Antonella Verzera Marisa Ziino Antonello Scacco Carmela Maria Lanza Agata Mazzaglia Vincenza Romeo Concetta Condurso 《Food Analytical Methods》2008,1(2):144-151
The research evidences the importance of linking chemical and sensory data for the wine characterization; in particular, the
Italian white wine made from Inzolia grapes has been considered. Inzolia is one of the most widespread native white grapes
in Sicily (Italy), and wine samples from two different areas (Monreale and Sambuca di Sicilia) have been analyzed. A headspace
solid-phase microextraction/gas chromatography–mass spectroscopy method has been developed, and 56 volatile components, esters,
fatty acids, alcohols, and terpenes have been identified; the method allows also the quantification of the main components,
namely, ethyl octanoate (banana, fruit, fat) (257.2–541.6 mg/l) and ethyl decanoate (fruity, oily, floral; 171.8–272.0 mg/l).
A good repeatability in terms of retention times and peak areas resulted. Sensory analysis was performed by ten trained judges
that evaluated eight attributes: two referring to appearance (yellow color and yellow reflex), four referring to aroma (fruity,
banana, ripened apple, and floral), and two referring to oral perception (acid and pungent). The volatile constituents and
the aroma sensory attributes were in agreement. 相似文献