745 research outputs found
Can a microscopic stochastic model explain the emergence of pain cycles in patients?
A stochastic model is here introduced to investigate the molecular mechanisms
which trigger the perception of pain. The action of analgesic drug compounds is
discussed in a dynamical context, where the competition with inactive species
is explicitly accounted for. Finite size effects inevitably perturb the
mean-field dynamics: Oscillations in the amount of bound receptors
spontaneously manifest, driven by the noise which is intrinsic to the system
under scrutiny. These effects are investigated both numerically, via stochastic
simulations and analytically, through a large-size expansion. The claim that
our findings could provide a consistent interpretative framework to explain the
emergence of cyclic behaviors in response to analgesic treatments, is
substantiated.Comment: J. Stat. Mech. (Proceedings UPON2008
A non-linear autoregressive model for indoor air-temperature predictions in smart buildings
In recent years, the contrast against energy waste and pollution has become mandatory and widely endorsed. Among the many actors at stake, the building sector energy management is one of the most critical. Indeed, buildings are responsible for 40% of total energy consumption only in Europe, affecting more than a third of the total pollution produced. Therefore, energy control policies of buildings (for example, forecast-based policies such as Demand Response and Demand Side Management) play a decisive role in reducing energy waste. On these premises, this paper presents an innovative methodology based on Internet-of-Things (IoT) technology for smart building indoor air-temperature forecasting. In detail, our methodology exploits a specialized Non-linear Autoregressive neural network for short-and medium-term predictions, envisioning two different exploitation: (i) on realistic artificial data and (ii) on real data collected by IoT devices deployed in the building. For this purpose, we designed and optimized four neural models, focusing respectively on three characterizing rooms and on the whole building. Experimental results on both a simulated and a real sensors dataset demonstrate the prediction accuracy and robustness of our proposed models
ANALYSIS OF THE TRADITIONAL PASSIVE SYSTEMS PERFORMANCE THROUGH THE APPLICATION OF CFD SOFTWARE
The need to reduce energy consumption is pushing the building design research to the evaluation of passive conditioning systems, since urban buildings are one of the major energy dissipater resulting in emission of CO2. This approach is not modern, but it is historically rooted in the architectural culture of the Mediterranean area and in the Middle East. The passive systems have ancient origins: they were developed to mitigate the summer heat and the winter cold. To understand the reasons that led to the development of passive systems, it should be remembered that about One-Fifth of the emerged planet surface and One-Third of the world's population live in conditions of warm-dry or hot-humid. In addition, most continental areas, even above high values of latitude (50\ub0), are characterized by climatic conditions with summer temperatures over the limit levels of comfort. Nowadays the scientific knowledge and the modern technologies allow to understand the working of passive systems in order to apply them on buildings to improve indoor comfort. This can be obtained through a new approach that involves the elaboration of design strategies based on the development of techniques and on computational and control tools. This work will show the results of a research that aims to verify the working of natural passive cooling systems employed in existing ancient buildings throughout CFD (Computational Fluid Dynamic) software application. Particularly we will define, through computational tools, models and study cases to compare and to set proposals able to actualize the original passive systems conceived and developed in an empirical way
Using HoloLens Mixed Reality to research correlations between language and movement: a case study
Communication can be defined as the understanding and exchanging of meaningful messages. The role of communication is central to the lives of human beings as, everyday, we use language to interact with the world around us. Linguistic skills play a fundamental role in this scenario and Language Disorders (LD) are impairments that limit the processing of linguistic information. Early and accurate identification of LD is thus essential to promote lifelong learning and well-being. From an evolutionary perspective, some human language constructs evolved from an ancestral motor system and share the same neural pathways in the Broca’s area of the brain. This suggests a correlation between action and language. If such a relationship is well established and reliable, it would be possible to use the former as a marker of the latter. The hypothesis of our work, in a nutshell, is that movement can be a predictor of language. To study this correlation, we developed C(H)o(L)ordination, a Mixed Reality (MR) application for HoloLens 2. The application offers several activities based on visual stimuli involving motor movements, which tap on the same skills needed to perform some language tasks. We performed an exploratory study with N=22 users to test the application usability and user experience. The results suggest that C(H)o(L)ordination is a usable and powerful tool to gather insights on the ongoing debate about language evolution and language disorders
Diauxie and co-utilization of carbon sources can coexist during bacterial growth in nutritionally complex environments
It is commonly thought that when multiple carbon sources are available, bacteria metabolize them either sequentially (diauxic growth) or simultaneously (co-utilization). However, this view is mainly based on analyses in relatively simple laboratory settings. Here we show that a heterotrophic marine bacterium, Pseudoalteromonas haloplanktis, can use both strategies simultaneously when multiple possible nutrients are provided in the same growth experiment. The order of nutrient uptake is partially determined by the biomass yield that can be achieved when the same compounds are provided as single carbon sources. Using transcriptomics and time-resolved intracellular 1H-13C NMR, we reveal specific pathways for utilization of various amino acids. Finally, theoretical modelling indicates that this metabolic phenotype, combining diauxie and co-utilization of substrates, is compatible with a tight regulation that allows the modulation of assimilatory pathways
Rapporto tecnico sulla valutazione della biomassa ittioplanctonica mediante l'utilizzo del Multi Plankton Sampler (MPS)
Il piano di campionamento della campagna oceanografica BANSIC'14, condotta a bordo della N/O "URANIA" dal 22 Luglio al 9 Agosto 2014, lungo transetti sotto costa e a largo delle coste meridionali della Sicilia, ha avuto l’obiettivo generale dello studio delle relazioni tra le strutture oceanografiche a mesoscala (vortici verticali ed orizzontali, upwelling, etc.) e le strutture spaziali dei fenomeni biologici relativi ai primi anelli della catena trofica (zooplancton, distribuzione e abbondanza di larve di piccoli pelagici e grandi pelagici) (vedi Rapporto finale BANSIC 2014) per la stima dell’abbondanza dello stock riproduttore. E' una campagna di ricerca nell'ambito del WP3 del progetto SSD-Pesca, finanziato dal MIUR su fondi MISE, a supporto della pesca italiana nelle Regioni Obiettivo 1 e del progetto RITMARE (SP2_WP4_AZ2_UO04). Il campionamento ittioplanctonico è inserito anche nel piano di lavoro del progetto regionale MIPAF-FAO “MedSudMed” (“Assessment and Monitoring of the Fishery Resources and the Ecosystems in the Straits of Sicily”).
Il campionamento dell’ittioplancton, durante questa campagna, oltre ai metodi tradizionali quali le reti di tipo Bongo, ha visto l'utilizzo del Multi Plankton Sampler (MPS) MultiNet.
I campionatori ittioplanctonici hanno lo scopo di prelevare porzioni di mesozooplancton da un massimo di 100 m fino alla superficie, in quanto le uova di pesci pelagici possiedono una galleggiabilità tale che nonostante le turbolenze superficiali dell’acqua, un campionamento entro i primi metri restituisce un dato affidabile della distribuzione anche se alcune uova possono trovarsi a maggiore profondità (Ahlstrom, 1959).
Il campionatore MPS consente, a differenza di altri strumenti, di prelevare la frazione di zooplancton d'interesse con diverse modalitĂ di campionamento: orizzontale, verticale e obliquo e, allo stesso tempo, permette di campionare a differenti quote di profonditĂ .
Le informazioni così ottenute sono state utilizzate per valutare la variazione della biomassa ittioplanctonica, l'abbondanza e la composizione delle specie lungo gli strati della colonna d'acqua anche in relazione alle componenti oceanografiche.
Grazie all'utilizzo di questo strumento è possibile validare e verificare alcune informazioni e acquisirne delle nuove sull’ecologia delle specie larvali e sul mesozooplancton, sul modo in cui queste si distribuiscono lungo la colonna d'acqua e sulle interazioni intra ed interspecifiche legate anche a fattori oceanografici. Ciò consente di ottenere maggiori informazioni e contribuire al miglioramento della comprensione della biologia e dell'ecologia delle specie rinvenute e, nel contempo, approfondire e migliorare le conoscenze sugli stadi di sviluppo di uova di specie ittiche che allo stadio embrionale sono ancora poco conosciuti
Characterization of Two Novel Variants of the Steroidogenic Acute Regulatory Protein Identified in a Girl with Classic Lipoid Congenital Adrenal Hyperplasia
Congenital adrenal hyperplasia (CAH) consists of several autosomal recessive disorders that inhibit steroid biosynthesis. We describe a case report diagnosed with adrenal insufficiency due to low adrenal steroids and adrenocorticotropic hormone excess due to lack of cortisol negative feedback signaling to the pituary gland. Genetic work up revealed two missense variants, p.Thr204Arg and p.Leu260Arg in the STAR gene, inherited by both parents (non-consanguineous). The StAR protein supports CYP11A1 enzyme to cleave the side chain of cholesterol and synthesize pregnenolone which is metabolized to all steroid hormones. We used bioinformatics to predict the impact of the variants on StAR activity and then we performed functional tests to characterize the two novel variants. In a cell system we tested the ability of variants to support cholesterol conversion to pregnenolone and measured their mRNA and protein expression. For both variants, we observed loss of StAR function, reduced protein expression and categorized them as pathogenic variants according to guidelines of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. These results fit the phenotype of the girl during diagnosis. This study characterizes two novel variants and expands the list of missense variants that cause CAH
Lactoferrin Binding to SARS-CoV-2 Spike Glycoprotein Blocks Pseudoviral Entry and Relieves Iron Protein Dysregulation in Several In Vitro Models
SARS-CoV-2 causes COVID-19, a predominantly pulmonary disease characterized by a burst of pro-inflammatory cytokines and an increase in free iron. The viral glycoprotein Spike mediates fusion to the host cell membrane, but its role as a virulence factor is largely unknown. Recently, the antiviral activity of lactoferrin against SARS-CoV-2 was demonstrated in vitro and shown to occur via binding to cell surface receptors, and its putative interaction with Spike was suggested by in silico analyses. We investigated the anti-SARS-CoV-2 activity of bovine and human lactoferrins in epithelial and macrophagic cells using a Spike-decorated pseudovirus. Lactoferrin inhibited pseudoviral fusion and counteracted the deleterious effects of Spike on iron and inflammatory homeostasis by restoring basal levels of iron-handling proteins and of proinflammatory cytokines IL-1β and IL-6. Using pull-down assays, we experimentally proved for the first time that lactoferrin binds to Spike, immediately suggesting a mechanism for the observed effects. The contribution of transferrin receptor 1 to Spike-mediated cell fusion was also experimentally demonstrated. In silico analyses showed that lactoferrin interacts with transferrin receptor 1, suggesting a multifaceted mechanism of action for lactoferrin. Our results give hope for the use of bovine lactoferrin, already available as a nutraceutical, as an adjuvant to standard therapies in COVID-19
Lactoferrin prevents LPS-induced decrease of the iron exporter ferroportin in human monocytes/macrophages.
Iron balance is tightly linked to inflammation and it has been demonstrated that many proteins involved in cellular iron management are up- or down-regulated by inflammatory stimuli, ultimately leading to iron retention in the reticuloendothelial system. Ferroportin is a key player in maintenance of correct iron homeostasis, because it is the only known mammalian cellular iron exporter. In this work we show that incubation of THP-1 monocytes/macrophages with lactoferrin prevents the LPS-induced decrease of ferroportin by reducing secretion of IL-6. © 2014 Springer Science+Business Media New York.Iron balance is tightly linked to inflammation
and it has been demonstrated that many proteins
involved in cellular iron management are up- or downregulated
by inflammatory stimuli, ultimately leading
to iron retention in the reticuloendothelial system.
Ferroportin is a key player in maintenance of correct
iron homeostasis, because it is the only known
mammalian cellular iron exporter. In this work we
show that incubation of THP-1 monocytes/macrophages
with lactoferrin prevents the LPS-induced
decrease of ferroportin by reducing secretion of IL-6
Variability of water mass properties in the Strait of Sicily in summer period of 1998–2013
The Strait of Sicily plays a crucial role in determining the water-mass exchanges and related properties between the western and eastern Mediterranean. Hydrographic measurements carried out from 1998 to 2013 allowed the identification of the main water masses present in the Strait of Sicily: a surface layer composed of Atlantic water (AW) flowing eastward, intermediate and deep layers mainly composed of Levantine intermediate water (LIW), and transitional eastern Mediterranean deep water (tEMDW) flowing in the opposite direction. Furthermore, for the first time, the signature of intermittent presence of western intermediate water (WIW) is also highlighted in the northwestern part of the study area (12.235â—¦ E, 37.705â—¦ N). The excellent area coverage allowed to highlight the high horizontal and vertical inter-annual variability affecting the study area and also to recognize the permanent character of the main mesoscale phenomena present in the surface water layer. Moreover, strong temperature-salinity correlations in the intermediate layer, for specific time intervals, seem to be linked to the reversal of surface circulation in the central Ionian Sea. The analysis of CTD data in deeper water layer indicates the presence of a large volume of tEMDW in the Strait of Sicily during the summers of 2006 and 2009.peer-reviewe
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