Analysis of Feedback Evaluation for Trust Management Models in the Internet of Things

The Internet of Things (IoT) is transforming the world into an ecosystem of objects that communicate with each other to enrich our lives. The devices’ collaboration allows the creation of complex applications, where each object can provide one or more services needed for global benefit. The information moves to nodes in a peer-to-peer network, in which the concept of trustworthiness is essential. Trust and Reputation Models (TRMs) are developed with the goal of guaranteeing that actions taken by entities in a system reflect their trustworthiness values and to prevent these values from being manipulated by malicious entities. The cornerstone of any TRM is the ability to generate a coherent evaluation of the information received. Indeed, the feedback generated by the consumers of the services has a vital role as the source of any trust model. In this paper, we focus on the generation of the feedback and propose different metrics to evaluate it. Moreover, we illustrate a new collusive attack that influences the evaluation of the received services. Simulations with a real IoT dataset show the importance of feedback generation and the impact of the new proposed attack

Glutamine Starvation Affects Cell Cycle, Oxidative Homeostasis and Metabolism in Colorectal Cancer Cells

Cancer cells adjust their metabolism to meet energy demands. In particular, glutamine addiction represents a distinctive feature of several types of tumors, including colorectal cancer. In this study, four colorectal cancer cell lines (Caco-2, HCT116, HT29 and SW480) were cultured with or without glutamine. The growth and proliferation rate, colony-forming capacity, apoptosis, cell cycle, redox homeostasis and metabolomic analysis were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT), flow cytometry, high-performance liquid chromatography and gas chromatography/mass spectrometry techniques. The results show that glutamine represents an important metabolite for cell growth and that its deprivation reduces the proliferation of colorectal cancer cells. Glutamine depletion induces cell death and cell cycle arrest in the GO/G1 phase by modulating energy metabolism, the amino acid content and antioxidant defenses. Moreover, the combined glutamine starvation with the glycolysis inhibitor 2-deoxy-D-glucose exerted a stronger cytotoxic effect. This study offers a strong rationale for targeting glutamine metabolism alone or in combination with glucose metabolism to achieve a therapeutic benefit in the treatment of colon cancer

Vitamin C Cytotoxicity and Its Effects in Redox Homeostasis and Energetic Metabolism in Papillary Thyroid Carcinoma Cell Lines.

High-dose of vitamin C (L-ascorbic acid, ascorbate) exhibits anti-tumoral effects, primarily mediated by pro-oxidant mechanisms. This cytotoxic effect is thought to affect the reciprocal crosstalk between redox balance and cell metabolism in different cancer types. Vitamin C also inhibits the growth of papillary thyroid carcinoma (PTC) cells, although the metabolic and redox effects remain to be fully understood. To shed light on these aspects, PTC-derived cell lines harboring the most common genetic alterations characterizing this tumor were used. Cell viability, apoptosis, and the metabolome were explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT), flow cytometry, and UHPLC/MS. Changes were observed in redox homeostasis, with increased reactive oxygen species (ROS) level and perturbation in antioxidants and electron carriers, leading to cell death by both apoptosis and necrosis. The oxidative stress contributed to the metabolic alterations in both glycolysis and TCA cycle. Our results confirm the pro-oxidant effect of vitamin C as relevant in triggering the cytotoxicity in PTC cells and suggest that inhibition of glycolysis and alteration of TCA cycle via NAD+ depletion can play an important role in this mechanism of PTC cancer cell death

"Bosniaco? Serbo geneticamente deforme". Gli effetti del patteggiamento negoziato nel processo di riconciliazione attraverso l'attivita' del Tpij. I casi Plavsic e Bralo.

La storia della giustizia internazionale e, più in generale, della giustizia di transizione. Questo lavoro è stato pensato come un luogo di incontro tra la storia, il diritto e la politica; sonda ed analizza il percorso, talvolta contraddittorio e fragile di costruzione e consolidamento delle istituzioni giudiziarie internazionali. Ciò in termini retributivi nella logica di corti e tribunali, tipici di una forma tradizionale e occidentale della giustizia penale che sono stati costituiti per dare corpo e sostanza ad alcune idee del primo Ottocento: quelle della risoluzione pacifica dei conflitti tra Stati e poi della salvaguardia del rispetto dei diritti umani e della punibilità dei crimini contro l’umanità. Oppure, nella dialettica ricostruttiva delle Commissioni per la Verità e per la Riconciliazione di fine Novecento, attraverso le quali si è cercato di dare vita ad un prototipo procedurale che assicurasse innanzitutto le basi conoscitive per un’elaborazione del passato (verità), offrisse la possibilità di garantirsi la collaborazione del maggior numero di individui coinvolti per una ricostruzione efficace della memoria collettiva e ponesse le condizioni per una politica di riparazione dei torti (risarcimento). Dopo la descrizione di alcuni significativi tentativi di avvicinamento compiuti nell’antichità, verranno esposte le tappe più significative di una storia recente, per scandire l’evoluzione del sistema internazionale di giustizia fino ai giorni nostri. Alla concezione classica, retributiva, di matrice occidentale delle dinamiche di elaborazione del passato si è tentato poi di accostare il senso alternato dell’evoluzione del sistema della giustizia di transizione. È il momento in cui si registra, con lo scetticismo che accompagna i primi passi dei Tribunali ad hoc (ICTY e ICTR) prima, e della ICC poi, l’avvio di un nuovo esperimento istituzionale che incede nella ricerca di altre vie, quella delle Commissioni per la Verità e la Riconciliazione o altri organi ibridi con funzioni para giudiziarie. L’altra faccia della medaglia, il recto della giustizia penale internazionale, che al paradigma retributivo processo-pena-espiazione contrappone l’archetipo ricostruttivo del risarcimento-verità-memoria, in una parola sola: riconciliazione. La novità assoluta nelle forme di elaborazione del passato e di contenimento della “resa dei conti” giunge, inaspettata, proprio dall’area dei Balcani, nascosta tra le pieghe regolative di un’istituzione giudiziaria plasmata sul modello “retributivo”: il Tribunale Penale Internazionale per i crimini commessi nella ex Jugoslavia (ICTY). In effetti, l’occasione fornita da due sentenze sottoposte ad analisi nel presente elaborato, evidenzia la svolta che il modello “retributivo” ha tentato di conferire al proprio rigido assetto classico-penalistico accostando e puntando con decisione la prua del diritto verso le acque calme della giustizia “riparativa”. Così, tra le righe delle ordinanze esaminate si accenna a termini come “riconciliazione”, “pacificazione”, sostantivi lontani dal rigore delle norme, ai quali la Corte comincia a fare esplicito riferimento. E poiché l’unica arma a disposizione dei collegi giudicanti è proprio la quantificazione della pena e la sua graduale determinazione, ne subordinano l’ampiezza dando vasto credito a questi criteri del tutto innovativi. È la miscellanea trasposizione di un effetto simbiotico tra legge e sentimento, tra diritto e prossimo che travalica le mura che cingono il processo, che vuole uscire al di fuori delle aule del Tribunale per diventare strumento efficace nel piano di ricostruzione politica e di educazione alla democrazia delle società balcaniche dilaniate da un terribile conflitto fratricida. Ma cosa rende possibile veicolare questi principi all’interno delle linee inflessibili e impermeabili del diritto occidentale? È la spinta che risiede proprio nella innovativa applicazione di un istituto legale già esistente nei Paesi che si riconoscono in sistemi giudiziari di common law, di stampo anglo-sassone: il plea bargaining. Ma l’elemento di novità nell’amministrazione della giustizia nella ex Jugoslavia non alberga nella consolidata pratica legale della trattativa negoziata, di per sé già conosciuta ed ampiamente sperimentata. L’originalità del cambiamento prodotto nel “modello balcanico” del plea bargaining è racchiusa in quel frammento distintivo che va oltre l’accordo fra le parti, che travalica la pur necessaria dichiarazione di colpevolezza dell’imputato, che si spinge al di là del parere conforme del collegio giudicante. Per avere successo, l’esempio slavo chiama in causa e pretende la sussistenza di altre variabili ad hoc: passi di riconciliazione, atti di pacificazione, rimorso, pentimento, richieste di perdono. Ed è ciò che risalterà, nella sua disarmante ineluttabilità, dalla disamina delle ordinanze proposte

The Impact of Network Impairments on the QoE of WebRTC applications: A Subjective study

WebRTC-based applications allow for real-time communications that are subject to network impairments affecting the end user's Quality of Experience (QoE). In this paper, we conducted subjective tests involving 20 people to investigate the conversational quality of a two-party WebRTC-based audiovisual telemeeting service. A dedicated system was implemented to introduce controlled network impairments (delay, jitter, and packet loss) to impair the communication between the parties. In addition, test participants had to rate the perceived QoE for the audio, the video, and the overall service, as well as the three emotional dimensions, i.e., valence, arousal, and dominance. Extensive results were obtained regarding the impact of the network impairments on the multimedia quality, the emotional dimensions, and the communication feasibility

Robust QUIC-Based Signalling for WebRTC in Impaired Networks

WebRTC (Web Real-Time Communication) has significantly impacted real-time communication in online applications, but the need for standardised signalling protocols still poses significant challenges to its full potential. This paper investigates the impact of using the QUIC (Quick UDP Internet Connections) protocol at the transport layer for signalling and information exchange in WebRTC. A new QUIC-based signalling server for WebRTC is proposed to address the challenge of establishing robust connections between peers in poor network conditions by leveraging the benefits of QUIC. To demonstrate its effectiveness, the performance of the proposed QUIC server is compared with that of the WebSocket-based signalling system, implemented by standard WebRTC solutions, across a network impaired by controlled network distortions, i.e., delay and packet loss. The results show that the proposed QUIC server provides a more robust and efficient solution (i.e., connection is always established and the average connection time is largely reduced) for WebRTC signalling in challenging network conditions

Fingerprint-based Positioning Method over LTE Advanced Pro Signals with GAN training contribute

Localization based on wireless signals has been introduced using a positioning method that relies on satellite navigation positioning systems, such as the Global Positioning System (GPS). The main issue with a passive localization system, such as this, is that although we would only gather anonymous information, we still need the user's approval. In this paper, a fingerprint-based localization approach based on Long-Term Evolution (LTE) Advanced Pro Signal is proposed. The authors analyzed received signal strength indication (RSSI) related to the communication between the base station and the user equipment (UE). Using a machine learning approach (i.e., a generative adversarial network - GAN), the proposed system allows understanding the correlation between RSSI and the position of the user in the space. The state of art related to fingerprinting-based localization has been drawn up as a costly and time-consuming offline training phase. The GAN will generate new models (RSSI, localization), and the experimental results show improvement in accuracy when compared with the effort to perform the offline phase. The results indicate great accuracy, 0.4 meters and 10 meters, respectively indoor, and outdoor environments case and the measurement campaign was fast and time saver

Modulatory Effect of Nicotinic Acid on the Metabolism of Caco-2 Cells Exposed to IL-1β and LPS

Inflammatory bowel diseases (IBD) are the most common gastrointestinal inflammatory pathologies. Previous work evidenced a lower content of nicotinic acid (NA) in feces of IBD patients compared to healthy subjects. In the present study, we aimed to understand the effects of NA on intestinal inflammation, as several studies reported its possible beneficial effect, and investigate its influence on inflammation-driven metabolism. NA was tested on a Caco-2 in-vitro model in which inflammation was induced with interleukin-1β (IL-1β) and lipopolysaccharide (LPS), two mayor proinflammatory compounds produced in IBD, that stimulate the production of cytokines, such as interleukin 8. A metabolomics approach, with gas chromatography–mass spectrometry (GC-MS) and nuclear proton magnetic resonance (1H-NMR), was applied to study the metabolic changes. The results showed that NA significantly reduced the level of IL-8 produced in both LPS and IL-1β stimulated cells, confirming the anti-inflammatory effect of NA also on intestinal inflammation. Moreover, it was demonstrated that NA treatment had a restoring effect on several metabolites whose levels were modified by treatments with IL-1β or LPS. This study points out a possible use of NA as anti-inflammatory compound and might be considered as a promising starting point in understanding the beneficial effect of NA in IBD

Vitamin C Cytotoxicity and Its Effects in Redox Homeostasis and Energetic Metabolism in Papillary Thyroid Carcinoma Cell Lines

High-dose of vitamin C (L-ascorbic acid, ascorbate) exhibits anti-tumoral effects, primarily mediated by pro-oxidant mechanisms. This cytotoxic effect is thought to affect the reciprocal crosstalk between redox balance and cell metabolism in different cancer types. Vitamin C also inhibits the growth of papillary thyroid carcinoma (PTC) cells, although the metabolic and redox effects remain to be fully understood. To shed light on these aspects, PTC-derived cell lines harboring the most common genetic alterations characterizing this tumor were used. Cell viability, apoptosis, and the metabolome were explored by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT), flow cytometry, and UHPLC/MS. Changes were observed in redox homeostasis, with increased reactive oxygen species (ROS) level and perturbation in antioxidants and electron carriers, leading to cell death by both apoptosis and necrosis. The oxidative stress contributed to the metabolic alterations in both glycolysis and TCA cycle. Our results confirm the pro-oxidant effect of vitamin C as relevant in triggering the cytotoxicity in PTC cells and suggest that inhibition of glycolysis and alteration of TCA cycle via NAD+ depletion can play an important role in this mechanism of PTC cancer cell death