96 research outputs found

    Dynamic adaptation of service-based applications: a design for adaptation approach

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    Abstract A key challenge posed by the Next Generation Internet landscape is that modern service-based applications need to cope with open and continuously evolving environments and to operate under dynamic circumstances (e.g., changes in the users requirements, changes in the availability of resources). Indeed, dynamically discover, select and compose the appropriate services in such environment is a challenging task. Self-adaptation approaches represent effective instruments to tackle this issue, because they allow applications to adapt their behaviours based on their execution environment. Unfortunately, although existing approaches support run-time adaptation, they tend to foresee the adaptation requirements and related solutions at design-time, while working under a "closed-world" assumption. In this article our objective is that of providing a new way of approaching the design, operation and run-time adaptation of service-based applications, by considering the adaptivity as an intrinsic characteristic of applications and from the earliest stages of their development. We propose a novel design for adaptation approach implementing a complete lifecycle for the continuous development and deployment of service-based applications, by facilitating (i) the continuous integration of new services that can easily join the application, and (ii) the operation of applications under dynamic circumstances, to face the openness and dynamicity of the environment. The proposed approach has been implemented and evaluated in a real-world case study in the mobility domain. Experimental results demonstrate the effectiveness of our approach and its practical applicability

    ATLAS: A new way to exploit world-wide mobility services

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    Abstract Despite the extent of the ecosystem of mobility services and the disparate functionalities they offer, organizing journeys by properly exploiting them and enhancing their interoperability is still a complex task. Moreover, the high degree of dynamicity characterizing modern service-based systems requires to make them able to self-adapt at runtime. In this paper, we present ATLAS , a world-wide travel assistant able to provide accurate and context-aware traveling solutions, supporting users for the whole travel duration. ATLAS has been realized by exploiting a tool to engineer adaptive by design service-based systems operating in open and dynamic environments

    An evaluation of the effectiveness of personalization and self-adaptation for e-Health apps

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    Context: There are many e-Health mobile apps on the apps store, from apps to improve a user\u27s lifestyle to mental coaching. Whilst these apps might consider user context when they give their interventions, prompts, and encouragements, they still tend to be rigid e.g., not using user context and experience to tailor themselves to the user. Objective: To better engage and tailor to the user, we have previously proposed a Reference Architecture for enabling self-adaptation and AI personalization in e-Health mobile apps. In this work we evaluate the end users’ perception, usability, performance impact, and energy consumption contributed by this Reference Architecture. Method: We do so by implementing a Reference Architecture compliant app and conducting two experiments: a user study and a measurement-based experiment. Results: Although limited in the number of participants, the results of our user study show that usability of the Reference Architecture compliant app is similar to the control app. Users’ perception was found to be positively influenced by the compliant app when compared to the control group. Results of our measurement-based experiment showed some differences in performance and energy consumption measurements between the two apps. The differences are, however, deemed minimal. Conclusions: Our experiments show promising results for an app implemented following our proposed Reference Architecture. This is preliminary evidence that the use of personalization and self-adaptation techniques can be beneficial within the domain of e-Health apps

    Agent-Based Framework for Self-Organization of Collective and Autonomous Shuttle Fleets

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    The mobility of people is at the center of transportation planning and decision-making of the cities of the future. In order to accelerate the transition to zero-emissions and to maximize air quality benefits, smart cities are prioritizing walking, cycling, shared mobility services and public transport over the use of private cars. Extensive progress has been made in autonomous and electric cars. Autonomous Vehicles (AV) are increasingly capable of moving without full control of humans, automating some aspects of driving, such as steering or braking. For these reasons, cities are investing in the infrastructure and technology needed to support connected, multi-modal transit networks that include shared electric Autonomous Vehicles (AV). The relationship between traditional public transport and new mobility services is in the spotlight and need to be rethought. This article proposes an agent-based simulation framework that allows for the creation and simulation of mobility scenarios to investigate the impact of new mobility modes on a city daily life. It lets traffic planners explore the cooperative integration of AV using a decentralized control approach. A prototype has been implemented and validated with data of the city of Trento

    Placido disk-based topography versus high-resolution rotating scheimpflug camera for corneal power measurements in keratoconic and post-lasik eyes: Reliability and agreement

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    AIM: To compare the repeatability/reproducibility of measurement by high-resolution Placido disk-based topography with that of a high-resolution rotating Scheimpflug camera and assess the agreement between the two instruments in measuring corneal power in eyes with keratoconus and post-laser in situ keratomileusis (LASIK). METHODS: One eye each of 36 keratoconic patients and 20 subjects who had undergone LASIK was included in this prospective observational study. Two independent examiners worked in a random order to take three measurements of each eye with both instruments. Four parameters were measured on the anterior cornea: steep keratometry (Ks), flat keratometry (Kf), mean keratometry (Km), and astigmatism (Ks-Kf). Intra-examiner repeatability and inter-examiner reproducibility were evaluated by calculating the within-subject standard deviation (Sw) the coefficient of repeatability (R), the coefficient of variation (CoV), and the intraclass correlation coefficient (ICC). Agreement between instruments was tested with the Bland-Altman method by calculating the 95% limits of agreement (95% LoA). RESULTS: In keratoconic eyes, the intra-examiner and inter-examiner ICC were >0.95. As compared with measurement by high-resolution Placido disk-based topography, the intra-examiner R of the high-resolution rotating Scheimpflug camera was lower for Kf (0.32 vs 0.88), Ks (0.61 vs 0.88), and Km (0.32 vs 0.84) but higher for Ks-Kf (0.70 vs 0.57). Inter-examiner R values were lower for all parameters measured using the high-resolution rotating Scheimpflug camera. The 95% LoA were -1.28 to +0.55 for Kf, -1.36 to +0.99 for Ks, -1.08 to +0.50 for Km, and -1.11 to +1.48 for Ks-Kf. In the post-LASIK eyes, the intra-examiner and inter-examiner ICC were >0.87 for all parameters. The intra-examiner and inter-examiner R were lower for all parameters measured using the high-resolution rotating Scheimpflug camera. The intra-examiner R was 0.17 vs 0.88 for Kf, 0.21 vs 0.88 for Ks, 0.17 vs 0.86 for Km, and 0.28 vs 0.33 for Ks-Kf. The inter-examiner R was 0.09 vs 0.64 for Kf, 0.15 vs 0.56 for Ks, 0.09 vs 0.59 for Km, and 0.18 vs 0.23 for Ks-Kf. The 95% LoA were -0.54 to +0.58 for Kf, -0.51 to +0.53 for Ks and Km, and -0.28 to +0.27 for Ks-Kf. CONCLUSION: As compared with Placido disk-based topography, the high-resolution rotating Scheimpflug camera provides more repeatable and reproducible measurements of Ks, Kf and Ks in keratoconic and post-LASIK eyes. Agreement between instruments is fair in keratoconus and very good in post-LASIK eyes

    Increase in newly diagnosed type 1 diabetes and serological evidence of recent SARS-CoV-2 infection: Is there a connection?

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    Several studies have investigated the correlation between the COVID-19 pandemic and the onset of type 1 diabetes (T1D) in children, reporting an increased incidence of T1D and severe diabetic ketoacidosis (DKA). This study aimed to investigate the infection by SARS-CoV-2 in children with newly-diagnosed T1D to explore a possible link between SARS-CoV-2 infection, T1D and DKA. Thirty-nine children with a T1D new onset between October 15, 2020, and April 15, 2021, were enrolled. SARS-CoV-2 infection was investigated through a polymerase chain reaction on the nasal swab, dosage of specific antibodies, and an anamnestic question form. Nine (23%) of them had antibodies directed toward SARS-CoV-2, and five (12%) had a history of recent SARS-CoV-2 infection in themselves or in their family. No molecular swabs were positive. Compared to the general pediatric population, the overall incidence of COVID-19 was 5.6 times higher in the T1D patients' group (p < 0.00001). Referring only to the cases in the metropolitan area, we find a net increase in the incidence of T1D compared to the 5 years preceding our study, by 50% compared to the same months in 2016/2017 and 2017/2018, by 69% compared to 2018/2019 and by 77% compared to 2019/2020. The same trend was observed regarding DKA cases. The attributable risk of the pandemic cohort compared to the previous year is 44%. The abnormal disproportion of SARS-CoV-2 infection between children with T1D and the pediatric reference population, with a ratio of 5.6, appears to support the causative role of SARS-CoV-2 in triggering the immune response underlying diabetes, as often described for other viral infections. The difficulty accessing care services during the pandemic, with a consequent diagnosis delay, does not justify the increase in observed T1D cases, which could to be directly linked to the pandemic. The acceleration of the immune process provoked by SARS-CoV-2 may play a suggestive role in the development of T1D with DKA. Multicenter studies are needed to deepen and fully understand the pathophysiological link between SARS-CoV-2 and the onset of T1D in children

    Erosione del suolo e inquinamento da nitrati: valutazione integrata e partecipativa delle misure agro-ambientali

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    L’Unione Europea richiede ai paesi membri una valutazione ex-post dei Piani di Sviluppo Rurale (PSR) per la quale fornisce un set di indicatori agro-ambientali (IAA) e di criteri di valutazione (Doc. STAR VI/43517/02, VI/12004/00, VI/8865/99). La Regione Marche, ad integrazione della valutazione indipendente del PSR condotta dalla Ati Ecoter-Resco-Unicab, ha commissionato agli autori (gruppo di lavoro SAPROV) una valutazione quantitativa dell’impatto delle misure agroambientali (basso impatto ambientale e biologico) sulle perdite di nitrati ed erosione idrica del suolo. In questo lavoro, si riportano in sintesi le “lessons learned” da questa esperienza, che è stata condotta attraverso l’integrazione di metodologie a diversa scala d’indagine relative ad aspetti agro-ambientali, politico-istituzionali e partecipative

    Sequestro potenziale di carbonio in sistemi colturali cerealicoli della collina marchigiana

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    Una delle sfide più importanti dell’agricoltura di questi anni è lo sviluppo di pratiche colturali in grado di aumentare il sequestro di carbonio organico nel suolo (Purakayastha et al. 2008). La scelta del sistema colturale e in particolare l’utilizzo di una bilanciata gestione della fertilizzazione può influenzare in misura molto rilevante il potenziale di incremento del carbonio organico nei suoli agrari (Lal, 2002). Il lavoro aveva l’obiettivo di valutare, attraverso sperimentazioni di campo e modelli di simulazione, l’impatto sulla sostanza organica del suolo di diverse modalità di fertilizzazione azotata nell’ambito di un avvicendamento asciutto frumento duro-mais della collina marchigiana

    Lipoprotein(a) Genotype Influences the Clinical Diagnosis of Familial Hypercholesterolemia

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    : Background Evidence suggests that LPA risk genotypes are a possible contributor to the clinical diagnosis of familial hypercholesterolemia (FH). This study aimed at determining the prevalence of LPA risk variants in adult individuals with FH enrolled in the Italian LIPIGEN (Lipid Transport Disorders Italian Genetic Network) study, with (FH/M+) or without (FH/M-) a causative genetic variant. Methods and Results An lp(a) [lipoprotein(a)] genetic score was calculated by summing the number risk-increasing alleles inherited at rs3798220 and rs10455872 variants. Overall, in the 4.6% of 1695 patients with clinically diagnosed FH, the phenotype was not explained by a monogenic or polygenic cause but by genotype associated with high lp(a) levels. Among 765 subjects with FH/M- and 930 subjects with FH/M+, 133 (17.4%) and 95 (10.2%) were characterized by 1 copy of either rs10455872 or rs3798220 or 2 copies of either rs10455872 or rs3798220 (lp(a) score ≥1). Subjects with FH/M- also had lower mean levels of pretreatment low-density lipoprotein cholesterol than individuals with FH/M+ (t test for difference in means between FH/M- and FH/M+ groups &lt;0.0001); however, subjects with FH/M- and lp(a) score ≥1 had higher mean (SD) pretreatment low-density lipoprotein cholesterol levels (223.47 [50.40] mg/dL) compared with subjects with FH/M- and lp(a) score=0 (219.38 [54.54] mg/dL for), although not statistically significant. The adjustment of low-density lipoprotein cholesterol levels based on lp(a) concentration reduced from 68% to 42% the proportion of subjects with low-density lipoprotein cholesterol level ≥190 mg/dL (or from 68% to 50%, considering a more conservative formula). Conclusions Our study supports the importance of measuring lp(a) to perform the diagnosis of FH appropriately and to exclude that the observed phenotype is driven by elevated levels of lp(a) before performing the genetic test for FH
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