Several cardiovascular and pulmonary models have been proposed in the last few decades. However, very few have addressed the interactions between these two systems. Our group has developed an ...integrated cardiopulmonary model (CP Model) that mathematically describes the interactions between the cardiovascular and respiratory systems, along with their main short-term control mechanisms. The model has been compared with human and animal data taken from published literature. Due to the volume of the work, the paper is divided in two parts. The present paper is on model development and normophysiology, whereas the second is on the model's validation on hypoxic and hypercapnic conditions. The CP Model incorporates cardiovascular circulation, respiratory mechanics, tissue and alveolar gas exchange, as well as short-term neural control mechanisms acting on both the cardiovascular and the respiratory functions. The model is able to simulate physiological variables typically observed in adult humans under normal and pathological conditions and to explain the underlying mechanisms and dynamics.
Il subappalto Albanese, Antonio
Revista boliviana de derecho : RBD,
2024
37
Journal Article
Odprti dostop
Il subappalto è il modello contrattuale più diffuso nell’ambito dell’integrazione fra le imprese;
esso non è invece adatto a regolare i rapporti tra imprese con dimensioni equivalenti e che intendono
...collaborare in posizione paritaria. Il subappalto è un vero e proprio appalto, che si caratterizza per
essere un contratto derivato da un altro appalto che ne costituisce il presupposto. Anche per il contratto
di subappalto, l’autonomia costituisce un elemento naturale. Il committente non ha azione diretta contro
il subappaltatore. L’autonomia del subappaltatore incide anche sul piano della responsabilità civile, con
riferimento ai danni arrecati a terzi nell’esecuzione dell’opera o del servizio.
The discipline of the contract regulates the supervening onerousness of the execution and the
supervening difficulty of the execution (so-called geological surprise), significantly detaching itself ...from the general
regulations on the contract. The art. 1664 of the Civil Code, in fact, contains a remedy to protect the contract,
unlike the art. 1467 of the civil code which provides for the termination of the contract, i.e. a termination remedy.
The hypotheses of the onerousness of the execution may include, among other things, the serious epidemiological
situation of recent years, with the measures limiting the freedom of economic initiative issued following the spread
of the «Covid-19» virus. With regard to the hypothesis of the difficulty of the execution, the broad interpretation,
which allows the application of the 2nd paragraph of the art. 1664 of the civil code even to non- «natural» causes,
is in line with the conservative aim of the discipline.
La disciplina dell’appalto regola la sopravvenuta onerosità dell’esecuzione e la sopravvenuta
difficoltà dell’esecuzione (c.d. sorpresa geologica), distaccandosi in maniera rilevante rispetto alle
normativa generale sul contratto. L’art. 1664 c.c., infatti, contiene un rimedio conservativo del contratto,
a differenza dell’art. 1467 c.c. che prevede la risoluzione del contratto, ossia un rimedio caducatorio. Tra
le ipotesi della sopravvenuta onerosità dell’esecuzione può farsi rientrare, tra l’altro, la grave situazione
epidemiologica degli ultimi anni, con i provvedimenti limitativi della libertà di iniziativa economica emanati
a seguito della diffusione del virus «Covid-19». Con riguardo all’ipotesi della sopravvenuta difficoltà
dell’esecuzione, l’interpretazione estensiva, che consente l’applicazione del 2° comma dell’art. 1664 c.c.
anche alle cause non «naturali», è in linea con il fine conservativo della disciplina.
Heart-lung interaction mechanisms are generally not well understood. Mechanical ventilation, for example, accentuates such interactions and could compromise cardiac activity. Thereby, assessment of ...ventilation-induced changes in cardiac function is considered an unmet clinical need. We believe that mathematical models of the human cardiopulmonary system can provide invaluable insights into such cardiorespiratory interactions. In this article, we aim to use a mathematical model to explain heart-lung interaction phenomena and provide physiologic hypotheses to certain contradictory experimental observations during mechanical ventilation. To accomplish this task, we highlight three model components that play a crucial role in heart-lung interactions: 1) pericardial membrane, 2) interventricular septum, and 3) pulmonary circulation that enables pulmonary capillary compression due to lung inflation. Evaluation of the model's response under simulated ventilation scenarios shows good agreement with experimental data from the literature. A sensitivity analysis is also presented to evaluate the relative impact of the model's highlighted components on the cyclic ventilation-induced changes in cardiac function.
With the advent of revolutionary technologies, such as virtualization and softwarization, a novel concept for 5G networks and beyond has been unveiled: Network Slicing. Initially driven by the ...research community, standardization bodies as 3GPP have embraced it as a promising solution to revolutionize the traditional mobile telecommunication market by enabling new business models opportunities. Network Slicing is envisioned to open up the telecom market to new players such as Industry Verticals, e.g., automotive, smart factories, e-health, etc. Given the large number of potential new business players, dubbed as network tenants, novel solutions are required to accommodate their needs in a cost-efficient and secure manner. In this paper, we propose NSBchain, a novel network slicing brokering (NSB) solution, which leverages on the widely adopted Blockchain technology to address the new business models needs beyond traditional network sharing agreements. NSBchain defines a new entity, the Intermediate Broker (IB), which enables Infrastructure Providers (InPs) to allocate network resources to IBs through smart contracts and IBs to assign and re-distribute their resources among tenants in a secure, automated and scalable manner. We conducted an extensive performance evaluation by means of an open-source blockchain platform that proves the feasibility of our proposed framework considering a large number of tenants and two different consensus algorithms.
Abstract The prevalence of the Brugada-type ECG and its natural history are still unclear. The Brugada syndrome is usually identified by a characteristic Brugada-type ECG that consists of ST ...elevation of a coved type in the precordial leads V1 to V3 and ventricular fibrillation that can lead to sudden cardiac death, although affected individuals may have a normal ECG. Mutations in the cardiac sodium channel gene SCN5A , which encodes the alpha-subunit of the human cardiac voltage-dependent Na+ channel (Na(v)1.5), are identified in 15–30% of patients with Brugada syndrome. Most SCN5A mutations lead to a ‘loss-of-function’ phenotype, reducing the Na+ current during the early phases of the action potential. Several nongenetic factors have been mentioned in the literature as possible inductors of the ECG pattern resembling Brugada syndrome. As such, a Brugada-type ECG may appear in some patients during febrile states and in those who are under the influence of cocaine and pharmaceutical drugs that have a sodium channel-blocking effect. It has been also reported that chest pain and ST elevation Brugada pattern occur during febrile states. We present a case of revelation of Brugada pattern in a 61-year-old Italian man complaining of pain in the left hipocondrium during a febrile state. Also this report confirms that Brugada pattern should be considered as one of differential diagnoses when we examine the patients during a febrile state.
Abstract
Background
Our aim was to analyze mortality attributable to carbapenem-resistant (CR) gram-negative bacilli (GNB) in patients with bloodstream infections (BSIs).
Methods
Prospective ...multicentric study including patients with GNB-BSI from 19 Italian hospitals (June 2018–January 2020). Patients were followed-up to 30 days. Primary outcomes were 30-day mortality and attributable mortality. Attributable mortality was calculated in the following groups: Klebsiella pneumoniae carbapenemase (KPC)–producing Enterobacterales, metallo-β-lactamases (MBL)–producing Enterobacterales, CR-Pseudomonas aeruginosa (CRPA), CR-Acinetobacter baumannii (CRAB). A multivariable analysis with hospital fixed-effect was built to identify factors associated with 30-day mortality. Adjusted OR (aORs) were reported. Attributable mortality was calculated according to the DRIVE-AB Consortium.
Results
Overall, 1276 patients with monomicrobial GNB BSI were included: 723/1276 (56.7%) carbapenem-susceptible (CS)-GNB, 304/1276 (23.8%) KPC-, 77/1276 (6%) MBL-producing CRE, 61/1276 (4.8%) CRPA, and 111/1276 (8.7%) CRAB BSI. Thirty-day mortality in patients with CS-GNB BSI was 13.7% compared to 26.6%, 36.4%, 32.8% and 43.2% in patients with BSI by KPC-CRE, MBL-CRE, CRPA and CRAB, respectively (P < .001). On multivariable analysis, age, ward of hospitalization, SOFA score, and Charlson Index were factors associated with 30-day mortality, while urinary source of infection and early appropriate therapy resulted protective factors. Compared to CS-GNB, MBL-producing CRE (aOR 5.86, 95% CI 2.72–12.76), CRPA (aOR 1.99, 95% CI 1.48–5.95) and CRAB (aOR 2.65, 95% CI 1.52–4.61) were significantly associated with 30-day mortality. Attributable mortality rates were 5% for KPC-, 35% for MBL, 19% for CRPA, and 16% for CRAB.
Conclusions
In patients with BSIs, carbapenem-resistance is associated with an excess of mortality, with MBL-producing CRE carrying the highest risk of death.
Evaluation of mortality attributable to antimicrobial resistance is challenging. We calculated attributable mortality in bacteremia by different carbapenem-resistant gram-negative bacilli. Carbapenem resistance is associated with an excess mortality (highest in MBL-producing Enterobacterales) even if active antibiotic therapy is started early.
A novel integrated physiological model of the interactions between the cardiovascular and respiratory systems has been in development for the past few years. The model has hundreds of parameters and ...variables representing the physical and physiological properties of the human cardiopulmonary system. It can simulate many dynamic states and scenarios. The description of the model and the results in normal resting conditions were presented in a companion paper (Albanese A, Cheng L, Ursino M, Chbat NW.Am J Physiol Heart Circ Physiol 310: 2016; doi:10.1152/ajpheart.00230.2014), where model predictions were compared against average population data from literature. However, it is also essential to test the model in abnormal or pathological conditions to prove its consistency. Hence, in this paper, we concentrate on testing the cardiopulmonary model under hypercapnic and hypoxic conditions, by comparing model's outputs to population-averaged cardiorespiratory data reported in the literature. The utility of this comprehensive model is demonstrated by testing the internal consistency of the simulated responses of a significant number of cardiovascular variables (heart rate, arterial pressure, and cardiac output) and respiratory variables (tidal volume, respiratory rate, minute ventilation, alveolar O2 and CO2 partial pressures) over a wide range of perturbations and conditions; namely, hypercapnia at 3-7% CO2 levels and hypoxia at 7-9% O2 levels with controlled CO2(isocapnic hypoxia) and without controlled CO2(hypocapnic hypoxia). Finally, a sensitivity analysis is performed to analyze the role of the main cardiorespiratory control mechanisms triggered by hypercapnia and hypoxia.
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