266 research outputs found
A physically-based approach for evaluating the hydraulic invariance in urban transformations
Transformation of urban areas satisfies hydraulic invariance (HI) if the maximum flow rate outgoing
the area stays unchanged. The HI can be respected by dimensioning appropriate water storage
volumes or low impact developments (LID) to balance the soil sealing and ground levelling effects.
In order to comply with HI, some Italian regional legislation and river basin authority provide for
the creation of storage tanks whose volume must be estimated through simple conceptual rainfallrunoff
models. In this work a physically based approach for evaluating HI is proposed. It is based on
interpolating the results from a large number of hydraulic simulations conducted using FullSWOF,
which is an open source code developed by the University of Orléans. In this software the shallow
water equations are solved using a finite volume scheme and friction laws and infiltration models
are included. Simulations have been carried out considering the effect of three properties of the
area, that is: the saturated hydraulic conductivity of soil, the slope of ground surface and the standard
deviation of ground elevation around the mean level. Using the results, interpolating laws for
the peak discharge and the critical rainfall duration as function of the three basin parameters have
been derived. A parametric hydrograph as a function of the basin parameters and rainfall duration
is defined and a HI evaluation method based on routing the parametric hydrograph is proposed.
The results from this approach have been compared with those from non-physically based methods
currently used, such as the direct rainfall approach and the linear reservoir approach. The comparison
shows that the difference between these conceptual methods with that one proposed here
is strongly dependent on the runoff coefficient value. It is also not possible to predict whether they
are conservative or not
The Waiver of Patent Protections for COVID-19 Vaccines During the Ongoing Pandemic and the Conspiracy Theories: Lights and Shadows of an Issue on the Ground
Vaccines against the coronavirus disease 2019 (COVID-19) currently constitute the main hope for the fight against the ongoing pandemic. Mass immunization against the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) should be considered as a global battle in which no country can be left behind, in particular the low-income countries. This last aspect may, in fact, favor the uncontrolled replication of the virus with the insurge of new variants. One of the possible solutions to limit this problem is the waiver of patent protections for COVID-19 vaccines.
On 2 October 2020, India and South Africa asked the World Trade Organization (WTO) to allow all countries to choose to neither grant nor enforce patents and other intellectual property (IP) related to COVID-19 drugs, vaccines, diagnostics and other technologies for the duration of the pandemic, until global herd immunity is achieved.
On 5 May 2021, the United States (US) administration announced the willingness to liberalize intellectual property concerning the COVID-19 vaccines (1, 2).
Although this issue is very interesting, its feasibility is particularly complex and intricate. Accordingly, there are discordant opinions among scholars and physicians on the real usefulness of patent liberalization (3–6). It has been suggested that an exception be made to the agreements establishing the World Trade Organization, in particular The Agreement on Trade Related Aspects of Intellectual Property Rights. This request would be based on the theory according to which the vaccines against the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) during a pandemic should be considered as a “common good”, similarly to water, or air. According to the Economic Theory of the Commons, which is supported by Elinor Ostrom, winner of the 2009 Nobel prize in Economics, the aforementioned terms should be considered in the Roman category of “res communes omnium”, meaning not appropriable and precluded from legal trade (7, 8).
From a practical point of view, the suspension of patent protections would limit the business models for the legitimate producers of COVID-19 vaccines. Among the potential strategies to encourage the waiver of patent protections it is possible to include: the direct donation of vaccines from the high-income countries, the reduction of the costs of the production lines, the shortening of the duration of patent protections, and a series of preferential patent waivers to countries that manufacture a large fraction of the global vaccines (e.g., India). One of the further possible solutions is represented by the solidarity by several governments or other agencies. This strategy is pursued, for example, by the program for COVID-19 Vaccines Global Access (COVAX). The latter is supported by Global Alliance for Vaccines and Immunization (GAVI), Coalition for Epidemic Preparedness Innovations (CEPI), and the World Health Organization (WHO) (9, 10)
In ludo veritas
Edward Burnett Tylor (1832-1917) fu uno dei padri fondatori dell’antropologia culturale. Per primo evidenziò il valore sociale della cultura, che definì «quel complesso insieme che comprende conoscenze, credenze, arte, valori morali, leggi, costumi, e ogni altra capacità e atteggiamento acquisiti da un uomo in quanto membro di una società». Durante la riunione del 14 marzo 1879 alla Royal Institution of Great Britain, Tylor fece un’insolita relazione del proprio lavoro. Il famoso antropologo era stato colpito dal fatto che il gioco del patolli, praticato dagli aztechi già prima della conquista spagnola, fosse molto simile al pachisi indiano. Ciò gli fece supporre che fossero fondate le teorie che ritenevano che la civilizzazione delle Americhe fosse avvenuta dall’Asia. Per questo, durante l’incontro con i colleghi della Royal Institution, Tylor espose le sue riflessioni sull’importanza del gioco come fattore culturale, sostenendo che la diffusione geografica delle attività ludiche è una testimonianza fondamentale dell’incontro tra civiltà e del processo di civilizzazione dell’ecumene. Aggiunse pure che i giochi resistono spesso nel tempo, anche in seguito a cambiamenti linguistici, religiosi o “dinastici”. Per questo sono rivelatori di interessanti indizi sulla storia dei popoli
Post-mortem corneal thickness measurements with a portable optical coherence tomography system: a reliability study
The purpose of this study was to determine the repeatability and reproducibility of post-mortem central corneal thickness (CCT) measurements by using a real-time, portable optical coherence tomography (OCT) system on an animal model, and to prospectively evaluate the time-course of post-mortem changes in CCT. Forty-six ocular globes of sheep (Ovis aries) were analyzed with a portable spectral-domain OCT device by two operators at different postmortem intervals (PMIs) as follows: immediately (i.e. within 10 minutes), at the 30(th) minute, at the 1(st), 6(th), 12(th), 24(th) and 48(th) hour, and later (up to the 96(th) hour). The coefficient of repeatability ranged from 0.3% to 3.5%, and coefficients of reproducibility ranged from 0.2% to 3.7% in the central region of the cornea. The intraclass correlation coefficients were particularly high at different PMIs, thus confirming good measurement reliability with the portable OCT. The average CCT decreased immediately and then increased thereafter, with two peaks at 6 and 24 hours after death. Our results suggest that portable OCT is a reliable tool for monitoring CCT variations after death and may be useful in characterizing corneas before explantation, detecting quantitative variations during post-mortem corneal degeneration or assessing changes in CCT for forensic implications
COVID-19 and Italian Healthcare Workers From the Initial Sacrifice to the mRNA Vaccine: Pandemic Chrono-History, Epidemiological Data, Ethical Dilemmas, and Future Challenges
On March 11, 2020, the World Health Organization (WHO) declared the coronavirus disease 2019 (COVID-19) outbreak a pandemic. Simultaneously, in Italy, in which the first case had occurred on February 18, the rigid phase of the lockdown began. The country has attracted worldwide attention, becoming at the same time a field of study both concerning the spread of the pandemic and advanced assessments of the effectiveness of political, public health, and therapeutic measures. The protagonists of the Italian crisis were the healthcare workers (HCWs) who were exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) without having any perception of what they were facing, courageously contributing to the containment of the epidemic to be defined by the media as “heroes.” However, in the first phase of the pandemic (March–May 2020), the price that the Italian Public Health System had to pay both in terms of the number of positive virus cases and deaths among the HCWs was beyond and represented a peculiarity compared to what happened in other countries. In the current study, after a summary of the evolution of the pandemic in Italy, we offer an analysis of the statistical data concerning contagions and deaths among healthcare workers (physicians in particular). In conclusion, we describe the critical issues that still need to be resolved and the future challenges facing healthcare workers and the general population
The architecture of corneal stromal striae on optical coherence tomography and histology in an animal model and in humans
The purpose of this study was to use a portable optical coherence tomography (OCT) for characterization of corneal stromal striae (CSS) in an ovine animal model and human corneas with histological correlation, in order to evaluate their architectural pattern by image analysis. Forty-six eyes from female adult sheep (older than 2 years), and 12 human corneas, were included in our study. The eyes were examined in situ by a portable OCT, without enucleation. All OCT scans were performed immediately after death, and then the eyes were delivered to a qualified histology laboratory. In the ovine animal model, CSS were detected with OCT in 89.1% (41/46) of individual scans and in 93.4% (43/46) of histological slices. In human corneas, CSS were found in 58.3% (7/12) of cases. In both corneal types, CSS appeared as “V”- or “X”-shaped structures, with very similar angle values of 70.8° ± 4° on OCT images and 71° ± 4° on histological slices (p ≤ 0.01). Data analysis demonstrated an excellent degree of reproducibility and inter-rater reliability of measurements (p < 0.001). The present study demonstrated that by using a portable OCT device, CSS can be visualized in ovine and human corneas. This finding suggests their generalized presence in various mammals. The frequent observation, close to 60%, of such collagen texture in the corneal stroma, similar to a ‘truss bridge’ design, permits to presume that it plays an important structural role, aimed to distribute tensile and compressive forces in various directions, conferring resilience properties to the cornea
Analysis of Forming Parameters Involved in Plastic Deformation of 441 Ferritic Stainless Steel Tubes
A welded stainless steel tube is a component used in several industrial applications. Its manufacturing process needs to follow specific requirements based on reference standards. This calls for a predictive analysis able to face some critical issues affecting the forming process. In this paper, a model was adopted taking into account the tube geometrical parameters that was able to describe the deformation process and define the best industrial practices. In this paper, the effect of different process parameters and geometric constraints on ferritic stainless steel pipe deformation is studied by finite element method (FEM) simulations. The model sensitivity to the input parameters is reported in terms of stress and tube thinning. The feasibility of the simulated process is assessed through the comparison of Forming Limit Diagrams. The comparison between the calculated and experimental results proved this approach to be a useful tool in order to predict and properly design industrial deformation processes
Fear of the COVID-19 and medical liability. Insights from a series of 130 consecutives medico-legal claims evaluated in a single institution during SARS-CoV-2-related pandemic
Objectives: The aim of the current work was to evaluate the frequency and the type of cases of medical liability from a single center in the first ten months of the pandemic as well as to identify critical issues associated with the organization of public health during the coronavirus disease 2019 pandemic.
Methods: We compared 130 cases evaluated for medical liability from March 2020 to January 2021 and compared with 159 cases from March 2019 to January 2020. The cases were divided in four pre-established groups: surgical error, diagnostic/therapeutic errors and nosocomial diseases, delays, and problems related to assistance.
Results: Analysis showed a significant increase in cases due to delay in treat-ment/hospitalization and shortages in health care of non-autonomous patients [χ2 (1, N = 289) = 5.6746, p = 0.02].
Conclusions: The work showed an increase in medical/legal cases regarding non-COVID-19 emergencies in which the outcome is related to the time of treatment and/or arrival at the hospital. There was also a rise in complaints of deficits in supervision and care for non-autonomous patients. Despite the persistence of preventive measures for the current pandemic, measures should be taken to improve health care in these categories of patients
- …