102 research outputs found
Generative AI: Challenges to higher education
Generative Artificial Intelligence has rapidly expanded its footprint of use in educational institutions. It has been embraced by students, faculty, and staff alike. The technology is capable of carrying out a sustained sequence of interactive dialogs and creating reasonably meaningful text. Not surprisingly it seems to be routinely used by faculty to generate questions and assignments, by students to submit assignments and aid in self-learning, and administration to create manuals, memoranda, and policy documents. With its potential to lead to significant social innovation, tethering on the verge of becoming a disruptive technology, it seems most unlikely that it will fade away without being fully enfolded into almost all aspects of academic and pedagogical activity. While it is early to predict the exact place of this technology in education, we present thoughts to aid deliberations and give a brief review of the opportunities and challenges
On the Structure of BV Entropy Solutions for Hyperbolic Systems of Balance Laws with General Flux Function
The paper describes the qualitative structure of BV entropy solutions of a general strictly hyperbolic system of balance laws with characteristic field either piecewise genuinely non- linear or linearly degenerate. In particular, we provide an accurate description of the local and global wave-front structure of a BV solution generated by a fractional step scheme combined with a wave-front tracking algorithm. This extends the corresponding results which were obtained in [Bianchini-Yu] for strictly hyperbolic system of conservation laws
Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure
Objective Asbestos is a known human carcinogen, with
evidence for malignant mesothelioma (MM), cancers of
lung, ovary, larynx and possibly other organs. MM rates
are predicted to increase with a power of time since first
exposure (TSFE), but the possible long-term attenuation
of the trend is debated. The asbestos ban enforced in
Italy in 1992 gives an opportunity to measure long-term
cancer risk in formerly exposed workers.
Methods Pool of 43 previously studied Italian asbestos
cohorts (asbestos cement, rolling stock, shipbuilding),
with mortality follow-up updated to 2010. SMRs were
computed for the 1970–2010 period, for the major
causes, with consideration of duration and TSFE, using
reference rates by age, sex, region and calendar period.
Results The study included 51 801 subjects (5741
women): 55.9% alive, 42.6% died (cause known
for 95%) and 1.5% lost to follow-up. Mortality was
significantly increased for all deaths (SMR: men: 1.05,
95% CI 1.03 to 1.06; women: 1.17, 95% CI to 1.12 to
1.22), all malignancies combined (SMR: men: 1.17, 95%
CI to 1.14 to 1.20; women: 1.33, 95% CI 1.24 to 1.43),
pleural and peritoneal malignancies (SMR: men: 13.28
and 4.77, 95% CI 12.24 to 14.37 and 4.00 to 5.64;
women: 28.44 and 6.75, 95% CI 23.83 to 33.69 and
4.70 to 9.39), lung (SMR: men: 1.26, 95% CI 1.21 to
1.31; women: 1.43, 95% CI 1.13 to 1.78) and ovarian
cancer (SMR=1.38, 95% CI 1.00 to 1.87) and asbestosis
(SMR: men: 300.7, 95% CI 270.7 to 333.2; women:
389.6, 95% CI 290.1 to 512.3). Pleural cancer rate
increased during the first 40 years of TSFE and reached a
plateau after.
Discussion The study confirmed the increased risk for
cancer of the lung, ovary, pleura and peritoneum but
not of the larynx and the digestive tract. Pleural cancer
mortality reached a plateau at long TSFE, coherently with
recent reports
The boundary Riemann solver coming from the real vanishing viscosity approximation
We study a family of initial boundary value problems associated to mixed
hyperbolic-parabolic systems:
v^{\epsilon} _t + A (v^{\epsilon}, \epsilon v^{\epsilon}_x ) v^{\epsilon}_x =
\epsilon B (v^{\epsilon} ) v^{\epsilon}_{xx}
The conservative case is, in particular, included in the previous
formulation.
We suppose that the solutions to these problems converge to a
unique limit. Also, it is assumed smallness of the total variation and other
technical hypotheses and it is provided a complete characterization of the
limit.
The most interesting points are the following two.
First, the boundary characteristic case is considered, i.e. one eigenvalue of
can be .
Second, we take into account the possibility that is not invertible. To
deal with this case, we take as hypotheses conditions that were introduced by
Kawashima and Shizuta relying on physically meaningful examples. We also
introduce a new condition of block linear degeneracy. We prove that, if it is
not satisfied, then pathological behaviours may occur.Comment: 84 pages, 6 figures. Text changes in Sections 1 and 3.2.3. Added
Section 3.1.2. Minor changes in other section
Use Scenarios in the Development of the Alexandria Digital Earth Prototype (ADEPT)
A user-centered, iterative design philosophy requires a common language between users, designers and builders to translate user needs into buildable specifications. This paper details the rationale, evolution and implementation of use scenarios
—structured narrative descriptions of envisioned system use—in the development of the Alexandria Digital Earth Prototype. This paper discusses the strengths of the scenario approach, obstacles to their use, and lessons learned in the overall development process
Monitoring Networks through Multiparty Session Types
In large-scale distributed infrastructures, applications are realised through communications among distributed components. The need for methods for assuring safe interactions in such environments is recognised, however the existing frameworks, relying on centralised verification or restricted specification methods, have limited applicability. This paper proposes a new theory of monitored π-calculus with dynamic usage of multiparty session types (MPST), offering a rigorous foundation for safety assurance of distributed components which asynchronously communicate through multiparty sessions. Our theory establishes a framework for semantically precise decentralised run-time enforcement and provides reasoning principles over monitored distributed applications, which complement existing static analysis techniques. We introduce asynchrony through the means of explicit routers and global queues, and propose novel equivalences between networks, that capture the notion of interface equivalence, i.e. equating networks offering the same services to a user. We illustrate our static–dynamic analysis system with an ATM protocol as a running example and justify our theory with results: satisfaction equivalence, local/global safety and transparency, and session fidelity
An overview on the approximation of boundary Riemann problems through physical viscosity
This note aims at providing an overview of some recent results concerning the viscous approximation of so-called boundary Riemann problems for nonlinear systems of conservation laws in small total variation regimes. \ua9 2016, Sociedade Brasileira de Matem\ue1tica
Impact of different exposure models and spatial resolution on the long-term effects of air pollution.
Abstract Long-term exposure to air pollution has been related to mortality in several epidemiological studies. The investigations have assessed exposure using various methods achieving different accuracy in predicting air pollutants concentrations. The comparison of the health effects estimates are therefore challenging. This paper aims to compare the effect estimates of the long-term effects of air pollutants (particulate matter with aerodynamic diameter less than 10 μm, PM10, and nitrogen dioxide, NO2) on cause-specific mortality in the Rome Longitudinal Study, using exposure estimates obtained with different models and spatial resolutions. Annual averages of NO2 and PM10 were estimated for the year 2015 in a large portion of the Rome urban area (12 × 12 km2) applying three modelling techniques available at increasing spatial resolution: 1) a chemical transport model (CTM) at 1km resolution; 2) a land-use random forest (LURF) approach at 200m resolution; 3) a micro-scale Lagrangian particle dispersion model (PMSS) taking into account the effect of buildings structure at 4 m resolution with results post processed at different buffer sizes (12, 24, 52, 100 and 200 m). All the exposures were assigned at the residential addresses of 482,259 citizens of Rome 30+ years of age who were enrolled on 2001 and followed-up till 2015. The association between annual exposures and natural-cause, cardiovascular (CVD) and respiratory (RESP) mortality were estimated using Cox proportional hazards models adjusted for individual and area-level confounders. We found different distributions of both NO2 and PM10 concentrations, across models and spatial resolutions. Natural cause and CVD mortality outcomes were all positively associated with NO2 and PM10 regardless of the model and spatial resolution when using a relative scale of the exposure such as the interquartile range (IQR): adjusted Hazard Ratios (HR), and 95% confidence intervals (CI), of natural cause mortality, per IQR increments in the two pollutants, ranged between 1.012 (1.004, 1.021) and 1.018 (1.007, 1.028) for the different NO2 estimates, and between 1.010 (1.000, 1.020) and 1.020 (1.008, 1.031) for PM10, with a tendency of larger effect for lower resolution exposures. The latter was even stronger when a fixed value of 10 μg/m3 is used to calculate HRs. Long-term effects of air pollution on mortality in Rome were consistent across different models for exposure assessment, and different spatial resolutions
Multicentric Atrial Strain COmparison between Two Different Modalities: MASCOT HIT Study
Two methods are currently available for left atrial (LA) strain measurement by speckle tracking echocardiography, with two different reference timings for starting the analysis: QRS (QRS-LASr) and P wave (P-LASr). The aim of MASCOT HIT study was to define which of the two was more reproducible, more feasible, and less time consuming. In 26 expert centers, LA strain was analyzed by two different echocardiographers (young vs senior) in a blinded fashion. The study population included: healthy subjects, patients with arterial hypertension or aortic stenosis (LA pressure overload, group 2) and patients with mitral regurgitation or heart failure (LA volume–pressure overload, group 3). Difference between the inter-correlation coefficient (ICC) by the two echocardiographers using the two techniques, feasibility and analysis time of both methods were analyzed. A total of 938 subjects were included: 309 controls, 333 patients in group 2, and 296 patients in group 3. The ICC was comparable between QRS-LASr (0.93) and P-LASr (0.90). The young echocardiographers calculated QRS-LASr in 90% of cases, the expert ones in 95%. The feasibility of P-LASr was 85% by young echocardiographers and 88% by senior ones. QRS-LASr young median time was 110 s (interquartile range, IR, 78-149) vs senior 110 s (IR 78-155); for P-LASr, 120 s (IR 80-165) and 120 s (IR 90-161), respectively. LA strain was feasible in the majority of patients with similar reproducibility for both methods. QRS complex guaranteed a slightly higher feasibility and a lower time wasting compared to the use of P wave as the reference
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