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131.
The introduction of smartphones and the accompanying profusion of mobile data services have had a profound effect on individuals’ lives. One of the most influential service categories is location-based services (LBS). Based on insights from behavioural decision-making, a conceptual framework is developed to analyse individuals’ decisions to use LBS, focusing on the cognitive processes involved in the decision-making. Our research is based on two studies. First, we investigate the use of LBS through semi-structured interviews of smartphone users. Second, we explore daily LBS use through a study based on diaries. The findings highlight that the decision to use LBS can be described by either a comparative mode based on the value of LBS in relation to other available options, or an intuitive mode in which past experiences trigger the use of heuristics. These modes in turn have positive influences on the continuance of LBS use and indicate changes in individuals’ information retrieval behaviours in everyday life. In particular, the distinct value dimension of LBS in specific contexts of use changes individuals’ behaviours towards accessing location-related information. 相似文献
132.
Ioannis Petrakis Eleni Drosataki Ioanna Stavrakaki Kleio Dermitzaki Dimitra Lygerou Myrto Konidaki Christos Pleros Nikolaos Kroustalakis Sevasti Maragkou Ariadni Androvitsanea Ioannis Stylianou Ioannis Zaganas Kostas Stylianou 《International journal of molecular sciences》2022,23(13)
Renal hypomagnesemia syndromes involving CNNM2 protein pathogenic variants are associated with variable degrees of neurocognitive dysfunction and hypomagnesemia. Here, we report a family with a novel CNNM2 p.Pro482Ala variant, presenting with overt hypomagnesemia and mild neurological involvement (autosomal dominant renal hypomagnesemia 6, HOMG6, MIM# 613882). Using a bioinformatics approach, we showed that the p.Pro482Ala amino acid substitution causes a 3D conformational change in CNNM2 structure in the cystathionin beta synthase (CBS) domain and the carboxy-terminal protein segment. A novel finding was that aldosterone inhibition with spironolactone helped to alleviate hypomagnesemia and symptoms in the proband. 相似文献
133.
L‐DOPA‐Coated Manganese Oxide Nanoparticles as Dual MRI Contrast Agents and Drug‐Delivery Vehicles 下载免费PDF全文
134.
Maria Stefanidou Vasiliki Pachta Stavroula Konopissi Fotini Karkadelidou Ioanna Papayianni 《Materials and Structures》2014,47(4):571-580
Structural mortars and plasters from cisterns and baths (thermes) from Roman, Byzantine and Ottoman period in Greece are analyzed in terms of their physico-mechanical, chemical, and microstructural characteristics, in order to find the key factors for their functionality. From the analysis it is found that their coherent and dense structure is due to the action of different mechanisms caused by the selection and combination of raw materials and the interaction with the special environment into which they served. The binding system is mixed, with the combination of hydrated lime and materials with pozzolanic properties. The aggregates are both siliceous and brick fragments of different granulometry, according to the mortar’s type (structural or plaster). The raw materials used as binders and aggregates and the technology practices during mortar application contribute to low porosity mortars with dense structure. Additionally, the environment of the cisterns and baths functioned on the benefit of the materials, as it favored the dilution of the calcite and the secondary phases formed in the mortars’ porous nature assisted towards the cohesiveness of their structure. The technology used for the production of mortars applied in baths and cisterns for a long period of time proves the high knowledge of materials’ behavior in order to produce durable constructions, resistant to highly deteriorating factors. 相似文献
135.
136.
Ioanna Nikitopoulou Dionysios Fanidis Konstantinos Ntatsoulis Panagiotis Moulos George Mpekoulis Maria Evangelidou Alice G. Vassiliou Vasiliki Dimakopoulou Edison Jahaj Stamatios Tsipilis Stylianos E. Orfanos Ioanna Dimopoulou Emmanouil Angelakis Karolina Akinosoglou Niki Vassilaki Argyrios Tzouvelekis Anastasia Kotanidou Vassilis Aidinis 《International journal of molecular sciences》2021,22(18)
Autotaxin (ATX; ENPP2) is a secreted lysophospholipase D catalyzing the extracellular production of lysophosphatidic acid (LPA), a pleiotropic signaling phospholipid. Genetic and pharmacologic studies have previously established a pathologic role for ATX and LPA signaling in pulmonary injury, inflammation, and fibrosis. Here, increased ENPP2 mRNA levels were detected in immune cells from nasopharyngeal swab samples of COVID-19 patients, and increased ATX serum levels were found in severe COVID-19 patients. ATX serum levels correlated with the corresponding increased serum levels of IL-6 and endothelial damage biomarkers, suggesting an interplay of the ATX/LPA axis with hyperinflammation and the associated vascular dysfunction in COVID-19. Accordingly, dexamethasone (Dex) treatment of mechanically ventilated patients reduced ATX levels, as shown in two independent cohorts, indicating that the therapeutic benefits of Dex include the suppression of ATX. Moreover, large scale analysis of multiple single cell RNA sequencing datasets revealed the expression landscape of ENPP2 in COVID-19 and further suggested a role for ATX in the homeostasis of dendritic cells, which exhibit both numerical and functional deficits in COVID-19. Therefore, ATX has likely a multifunctional role in COVID-19 pathogenesis, suggesting that its pharmacological targeting might represent an additional therapeutic option, both during and after hospitalization. 相似文献
137.
Ioanna Papatheodorou Eleftheria Galatou Georgios-Dimitrios Panagiotidis Ta Ravingerov Antigone Lazou 《International journal of molecular sciences》2021,22(12)
Accumulating evidence support the cardioprotective properties of the nuclear receptor peroxisome proliferator activated receptor β/δ (PPARβ/δ); however, the underlying mechanisms are not yet fully elucidated. The aim of the study was to further investigate the mechanisms underlying PPARβ/δ-mediated cardioprotection in the setting of myocardial ischemia/reperfusion (I/R). For this purpose, rats were treated with PPARβ/δ agonist GW0742 and/or antagonist GSK0660 in vivo and hearts were subjected to ex vivo global ischemia followed by reperfusion. PPARβ/δ activation improved left ventricular developed pressure recovery, reduced infarct size (IS) and incidence of reperfusion-induced ventricular arrhythmias while it also up-regulated superoxide dismutase 2, catalase and uncoupling protein 3 resulting in attenuation of oxidative stress as evidenced by the reduction in 4-hydroxy-2-nonenal protein adducts and protein carbonyl formation. PPARβ/δ activation also increased both mRNA expression and enzymatic activity of aldehyde dehydrogenase 2 (ALDH2); inhibition of ALDH2 abrogated the IS limiting effect of PPARβ/δ activation. Furthermore, upregulation of PGC-1α and isocitrate dehydrogenase 2 mRNA expression, increased citrate synthase activity as well as mitochondrial ATP content indicated improvement in mitochondrial content and energy production. These data provide new mechanistic insight into the cardioprotective properties of PPARβ/δ in I/R pointing to ALDH2 as a direct downstream target and suggesting that PPARβ/δ activation alleviates myocardial I/R injury through coordinated stimulation of the antioxidant defense of the heart and preservation of mitochondrial function. 相似文献
138.
Heiner K. Berthold Jessica Mertens Julia Birnbaum Susanne Brämswig Thomas Sudhop P. Hugh R. Barrett Klaus von Bergmann Ioanna Gouni-Berthold 《Lipids》2010,45(6):491-500
Statins decrease apoB-100-containing lipoproteins by increasing their fractional catabolic rates through LDL receptor-mediated
uptake. Their influence on hepatic secretion of these lipoproteins is controversial. The objective of the study was to examine
the influence of simvastatin on the secretion of apoB-100-containing lipoproteins in fasting non-obese subjects. Turnover
of apoB-100-containing lipoproteins was investigated using stable isotope-labeled tracers. Multicompartmental modeling was
used to derive kinetic parameters. Eight male subjects (BMI 25 ± 3 kg/m2) with mild hypercholesterolemia (LDL cholesterol 135 ± 30 mg/dL) and normal triglycerides (111 ± 44 mg/dL) were examined
under no treatment (A), under chronic treatment with simvastatin 40 mg/day (B) and after an acute-on-chronic dosage of 80 mg
simvastatin under chronic simvastatin treatment (C). Lipoprotein concentrations changed as expected under 40 mg/day simvastatin.
Fractional catabolic rates increased in IDL and LDL but not in VLDL fractions versus control [VLDL +35% in B (n.s.) and +21%
in C (n.s.); IDL +169% in B (P = 0.08) and +187% in C (P = 0.032); LDL +87% in B (P = 0.025) and +133% in C (P = 0.025)]. Chronic (B) and acute-on-chronic simvastatin treatment (C) did not affect lipoprotein production rates [VLDL −8
and −13%, IDL +47 and +38%, and LDL +19 and +30% in B and C, respectively (all comparisons n.s.)]. The data indicate that
simvastatin does not influence the secretion of apoB-100-containing lipoproteins in non-obese subjects with near-normal LDL
cholesterol concentrations. 相似文献
139.
Afroditi Chatzifragkou Ioanna Petrou Chryssavgi Gardeli Michael Komaitis Seraphim Papanikolaou 《Journal of the American Oil Chemists' Society》2011,88(12):1955-1964
Aim of the present study was to identify the chemical composition of Origanum vulgare L. essential oil and to investigate its effect on the biochemical behavior of the yeast Yarrowia lipolytica. Twenty-three compounds were identified by GC–MS analysis, representing the 92.3% (w/w) of the total essential oil of the plant. Carvacrol (56.3%) and thymol (16.4%) were the major components. Additionally, shake-flask cultivations of Y. lipolytica were performed, with various essential oil additions (0.05–2 mL/L of medium) on glycerol-based media. Growth was affected even at low concentrations (0.05 mL/L), while in higher essential oil concentrations, strong inhibition phenomena were observed. A tolerance-threshold concentration for the strain was hence established at 0.15 mL/L of oil. Furthermore, the presence of the essential oil in the culture medium resulted in changes in the composition of the intra-cellular lipids of the yeast. Specifically, oil addition to nitrogen-limited cultures to a level >0.15 mL/L caused a substantial increase in the percentage of saturated fatty acids (C16:0 and C18:0) in the lipid composition of the yeast Y. lipolytica. 相似文献
140.
Celestino Grifa Laetitia Cavassa Alberto De Bonis Chiara Germinario Vincenza Guarino Francesco Izzo Ioanna Kakoulli Alessio Langella Mariano Mercurio Vincenzo Morra 《Journal of the American Ceramic Society》2016,99(10):3467-3475
Archeological campaigns along the track of the Domitian road in Cuma resulted in the recovery of a large amount of potshards and crucible fragments (both open and closed forms), covered with residues of blue and green frits, respectively. Typological analysis of the crucibles combined with mineralogical and petrological analyses on the ceramic body and frit residues revealed that the forms are intimately related to the technological data. Newly formed calcium silicates indicate high firing treatments of crucibles during pigment making (not lower than 950°C). In particular, different working temperatures for the two types of crucibles have been estimated by the presence/absence of sodalite‐nosean feldspathoid. This mineral formed after the reaction of Si‐Al‐rich material (the sintered ceramic body) and alkalis transferred to ceramics via chemical diffusion during the pigment synthesis. Thus, the estimated working temperatures are higher for closed forms (>1100°C) and lower for the open ones (950–1050°C). This different thermal treatment perfectly fits with the temperatures of green and blue pigment synthesis; higher temperatures for green pigments allowed the formation of abundant Cu‐bearing glassy phase, whereas, blue pigment is prone to the formation and thermal stability of cuprorivaite crystals (950–1050°C). Moreover, the two frits showed similar recipes (quartz‐feldspar‐calcite‐rich sand) with the exception of more abundant Cu‐bearing colorant agent in blue hue and higher proportion of alkaline flux in green frit. The obtained data suggested that crucibles were a fundamental tool for pigment manufacturing, likely one of the best example of ancient technical ceramics, as they permitted controlling the temperatures along with the fuel and the treatment time. Combining analytical and archeological data, the production and the technology of the two colored compounds identified as Egyptian Blue and Green frits in ancient Cuma has been inferred. Finally, considering the Vitruvius excerpt that identified an Egyptian Blue production in Puteoli, the area of production can be widen up to the northern Phlegraean Fields, also including Cumae and Liternum. 相似文献