883 research outputs found

    Advanced technologies to target cardiac cell fate plasticity for heart regeneration

    Get PDF
    The adult human heart can only adapt to heart diseases by starting a myocardial remodeling process to compensate for the loss of functional cardiomyocytes, which ultimately develop into heart failure. In recent decades, the evolution of new strategies to regenerate the injured myocardium based on cellular reprogramming represents a revolutionary new paradigm for cardiac repair by targeting some key signaling molecules governing cardiac cell fate plasticity. While the indirect reprogramming routes require an in vitro engineered 3D tissue to be transplanted in vivo, the direct cardiac reprogramming would allow the administration of reprogramming factors directly in situ, thus holding great potential as in vivo treatment for clinical applications. In this framework, cellular reprogramming in partnership with nanotechnologies and bioengineering will offer new perspectives in the field of cardiovascular research for disease modeling, drug screening, and tissue engineering applications. In this review, we will summarize the recent progress in developing innovative therapeutic strategies based on manipulating cardiac cell fate plasticity in combination with bioengineering and nanotechnology-based approaches for targeting the failing heart

    A high efficiency input/output coupler for small silicon photonic devices

    Get PDF
    Coupling light from an optical fibre to small optical waveguides is particularly problematic in semiconductors, since the refractive index of the silica fibre is very different from that of a semiconductor waveguide. There have been several published methods of achieving such coupling, but none are sufficiently efficient whilst being robust enough for commercial applications. In this paper experimental results of our approach called a Dual-Grating Assisted Directional Coupler, are presented. The principle of coupling by this novel method has been successfully demonstrated, and a coupling efficiency of 55% measured

    The key role of micrornas in self-renewal and differentiation of embryonic stem cells

    Get PDF
    Naïve pluripotent embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs) represent distinctive developmental stages, mimicking the pre-and the post-implantation events during the embryo development, respectively. The complex molecular mechanisms governing the transition from ESCs into EpiSCs are orchestrated by fluctuating levels of pluripotency transcription factors (Nanog, Oct4, etc.) and wide-ranging remodeling of the epigenetic landscape. Recent studies highlighted the pivotal role of microRNAs (miRNAs) in balancing the switch from self-renewal to differentiation of ESCs. Of note, evidence deriving from miRNA-based reprogramming strategies underscores the role of the non-coding RNAs in the induction and maintenance of the stemness properties. In this review, we revised recent studies concerning the functions mediated by miRNAs in ESCs, with the aim of giving a comprehensive view of the highly dynamic miRNA-mediated tuning, essential to guarantee cell cycle progression, pluripotency maintenance and the proper commitment of ESCs

    Potential energy savings from circular economy scenarios based on construction and agri-food waste in Italy

    Get PDF
    In this study, our aim was to explore the potential energy savings obtainable from the recycling of 1 tonne of Construction and Demolition Waste (C&DW) generated in the Metropolitan City of Naples. The main fraction composing the functional unit are mixed C&DW, soil and stones, concrete, iron, steel and aluminium. The results evidence that the recycling option for the C&DW is better than landfilling as well as that the production of recycled aggregates is environmentally sustainable since the induced energy and environmental impacts are lower than the avoided energy and environmental impacts in the life cycle of recycled aggregates. This LCA study shows that the transition to the Circular Economy offers many opportunities for improving the energy and environmental performances of the construction sector in the life cycle of construction materials by means of internal recycling strategies (recycling C&DW into recycled aggregates, recycled steel, iron and aluminum) as well as external recycling by using input of other sectors (agri-food by-products) for the manufacturing of construction materials. In this way, the C&D sector also contributes to realizing the energy and bioeconomy transition by disentangling itself from fossil fuel dependence

    Magneto-seismic interpretation of subsurface volcanism in the Gaeta Gulf (Italy, Tyrrhenian Sea)

    Get PDF
    The occurrence of a former subaerial volcanic edifice off the Volturno River (Tyrrhenian Sea, Gulf of Gaeta) in the 41°N parallel is suggested by joint interpretation of multichannel seismic lines and ship-borne magnetic data. In the Campanian region igneous (volcanic) rocks are very close to the carbonate Mesozoic basement and seismics cannot always discriminate between them. A joint seismic-magnetic analysis was very effective in assessing the lithological nature of the bodies evidenced by both geophysical methods. Distortion analysis showed that the main magnetic source in the area is characterised by a not normal-polarity direction of the magnetization, similar to other Pleistocene volcanoes in the Tyrrhenian region. Hence we argued that the overall magmatic emplacement for this source occurred during a reverse-polarity chron, very likely the 0.78-1.78 Ma time span. This magnetically-derived time constraint is in agreement with seismic stratigraphy that shows that the entire volcano is sealed by the Volturno River prograding delta from Middle Pleistocene to Present in age. Our interpreted volcano belongs to a set of inferred onshore and offshore volcanic edifices all lying along the 41°N paralle

    third order bragg grating filters in small soi waveguides

    Get PDF
    Third order grating filters fabricated in small Silicon-on-Insulator rib waveguides are demonstrated. Variations in grating etch depth and duty cycle are considered, and a maximum experimental reflection of 42% is demonstrated for gratings of 1500 µm in length, with a grating period of approximately 689nm and an etch depth of 200nm. Agreement with modeling is shown to be good

    European Society for Medical Oncology (ESMO) 2018 Congress Twitter analysis: from ethics to results through the understanding of communication and interaction flows.

    Get PDF
    Twitter is a microblogging service providing a platform for social networking. For medical information, Twitter is an interesting channel for sharing and spreading information and as an engagement platform for different stakeholders. Benefits and caveats of uncontrolled medical information must be carefully pondered, considering the possible intended and unintended adverse outcomes of uncontrolled influencing. The aim of this study was to describe the non-commercial content shared on Twitter and to analyse the level of influence of commercial tweeters during the European Society of Medical Oncology (ESMO) 2018 annual meeting held in Munich. A retrospective analysis of the tweets shared in the period 19-23 October 2018 indexed with the hashtag #ESMO18 or #ESMO2018 was performed; methodology of systematic reviews was mirrored. Commercial tweeters (pharmaceutical and biotechnology companies, device manufacturers and spam tweeters) were excluded from the primary analysis, and only non-commercial tweets from and about the congress were included. Tweets were analysed using a network analytical tool (NodeXL). A total of 7100 tweets posted by 1334 tweeters were identified for the period of interest. Less than 10% of tweeters were identified as commercial, posting 15.7% of tweets and receiving almost one-quarter of retweets. However, pharmaceutical and biotech tweeters were substantially less likely to be mentioned by other tweeters. All of the top 10 retweeters of non-commercial content were clinicians and/or professional organisations, in stark contrast with the commercial content. The use of social networks in medical meetings, including oncology, is increasing for real-time communication and informed opinion-making. The uncontrolled spread of information on Twitter can both stimulate discussions on non-official and non-canonical channels of communication and provide uncontrolled influencing of diverse stakeholders. The disclosure of financial declarations of interest on Twitter could enhance the transparency of the information, as is already happening in medical journals

    THE REASONS OF THE VERNACULAR ARCHITECTURE FOR THE REGULATION OF CONTEMPORARY INTERVENTIONS. TWO EXAMPLES OF RURAL ARCHITECTURE ON DANUBE DELTA AND THE VESUVIUS

    Get PDF
    Abstract. The development and growth of the territory has for centuries been conditioned by the availability of resources on site. The minor architecture which is presented as a vast and varied repertoire of unique architectural forms, perfected over time to meet the needs of living places, is the repository of the formal and cultural testimonies that represent the integration between man and environment, which took place in a constant process of adaptation and enhancement of limits and resources in terms of climate, materials, soil morphology and geology. The "not only formal" result of this growth process is a consolidated iconography that summarizes the profound reasons for building through techniques developed according to the characteristics of the available materials and the needs of life and daily work, an absolute synthesis between form and function that gives rise to the repertoire of the lexicon of the architecture of a place and of the landscape. Starting from these reflections, the proposed study seeks to investigate the reasons for the constructive lexicon of some examples of vernacular architecture related to different contexts, identifying the reasons for the constructive choices in terms of relationships between the function of technical elements and construction characteristics; the purpose of this approach is to regulate constructive interventions in consolidated settlements of vernacular architecture by proposing a study methodology that highlights the rules and reasons for those constructive choices so that purely formal distortions and misunderstandings do not occur in current practices. The selected case studies are the rural settlements of Terzigno, a municipality in the province of Naples (Italy) on the slopes of Vesuvius and some of the rural settlements in the Danube Delta, in Romania

    Energy level statistics of electrons in a 2D quasicrystal

    Full text link
    A numerical study is made of the spectra of a tight-binding hamiltonian on square approximants of the quasiperiodic octagonal tiling. Tilings may be pure or random, with different degrees of phason disorder considered. The level statistics for the randomized tilings follow the predictions of random matrix theory, while for the perfect tilings a new type of level statistics is found. In this case, the first-, second- level spacing distributions are well described by lognormal laws with power law tails for large spacing. In addition, level spacing properties being related to properties of the density of states, the latter quantity is studied and the multifractal character of the spectral measure is exhibited.Comment: 9 pages including references and figure captions, 6 figures available upon request, LATEX, report-number els

    Geometria e modellazione di un sistema di retro-scorrimenti attivosulla base di dati di geofisica marina ad alta risoluzione:la Dorsale di Amendolara (Golfo di Taranto).

    Get PDF
    Nuovi dati sismici ad alta (Sparker) ed altissima (Subbottm Chirp) risoluzione, acquisiti durante la Campagna Oceanografica “Teatioca_2010”, integrati da dati sismici multicanale ad alta penetrazione, pubblici disponibili sul sito www.videpi.com, calibrati con pozzi profondi, batimetrici multifascio e carotaggi, rivelano che la dorsale di Amendolara, estensione sottomarina della zona frontale del sistema a thrust dell’Appennino meridionale, è stata controllata nel Quaternario da un sistema di retro-scorrimenti e faglie transpressive (ATFS) che dislocano verso SW la catena mio-pliocenica NE-vergente. Il pacco di sequenze deposizionali attribuito, sulla base della facies sismica e della presenza di discordanze controllate dalle oscillazioni glacio-eustatiche, al Pleistocene medio-superiore risulta piegato in maniera consistente con le strutture desumibili dai profili multicanale. I dati morfometrici e sismici documentano che la dorsale, orientata NW-SE, è formata da 3 banchi lunghi ~10-20 km, cresciuti sopra rampe di sovrascorrimenti ciechi (~2 km) disposti en-echelon a formare un sistema segmentato. Sono stati individuati e modellati i segmenti di Amendolara a NW e Cariati a SE, collegati da una più piccola rampa laterale (segmento di Rossano). La modellazione numerica calibrata sui dati batimetrici e sismici indica che le rampe hanno inclinazione di ~45° e sono radicate a ~10 km di profondità a possibili scollamenti o strutture maggiori. I tassi di scorrimento negli ultimi 4-500 ka, calcolati per i segmenti sulla base degli strati di crescita nei bacini sin tettonici variano da 0.5-0-9 mm/a per il segmento di Amendolara a 0.35-0.5 mm/a per quello di Cariati. L’ATFS coincide con una fascia di moderata sismicità (Mw<4.7) con meccanismi focali inversi o transpressivi. L’orientazione degli assi di strain incrementale (sismico) e finito (geologico, come documentano i dati a terra) suggerisce per i segmenti dell’ATFS un movimento da inverso a obliquo sinistro. In base alla dimensione dei segmenti di faglia, nell’ipotesi di deformazione puramente elastica, si stima una magnitudo potenziale massima per l’ATFS di M~6.1-6.4, ma è verosimile che buona parte della deformazione sia asismica o microsismica. L’epicentro macrosismico del terremoto del 1988 (Mw=4.9) ricade su un tratto del segmento di Cariati che mostra rotture a fondo mare e possibile risalita di fluidi localizzata lungo strutture attive. La crescita dell’ATFS è stata verosimilmente controllata da un interfaccia meccanica tra la spessa crosta apula e la crosta ionica assottigliata o in parte oceanica, quando in tempi recenti la convergenza Adria-Europa ha prevalso sull’arretramento della cerniera della subduzione ionica
    corecore