An artificial neural network approach for modelling the ward atmosphere in a medical unit

Artificial neural networks (ANNs) have been developed, implemented and tested on the basis of a four-year-long experimental data set, with the aim of analyzing the performance and clinical outcome of an existing medical ward, and predicting the effects that possible readjustments and/or interventions on the structure may produce on it. Advantages of the ANN technique over more traditional mathematical models are twofold: on one hand, this approach deals quite naturally with a large number of parameters/variables, and also allows to identify those variables which do not play a crucial role in the system dynamics; on the other hand, the implemented ANN can be more easily used by a staff of non-mathematicians in the unit, as an on-site predictive tool. As such, the ANN model is particularly suitable for the case study. The predictions from the ANN technique are then compared and contrasted with those obtained from a generalized kinetic approach previously proposed and tested by the authors. The comparison on the two case periods shows the ANN predictions to be somewhat closer to the experimental values. However, the mean deviations and the analysis of the statistical coefficients over a span of multiple years suggest the kinetic model to be more reliable in the long run, i.e., its predictions can be considered as acceptable even on periods that are quite far away from the two case periods over which the many parameters of the model had been optimized. The approach under study, referring to paradigms and methods of physical and mathematical models integrated with psychosocial sciences, has good chances of gaining the attention of the scientific community in both areas, and hence of eventually obtaining wider diffusion and generalization.

Quantitative Analysis by 3D Graphics of Thoraco-Abdominal Surface Shape and Breathing Motion

Chest wall motion can provide information on respiratory muscles' action and on critical vital signs, like respiration and cardiac activity. The chest wall is a structure with three compartments that are independent to each other and can move paradoxically according to the pathophysiology of the disease. Opto-electronic plethysmography (OEP) allows for non-invasively 3D tracking of body movements. We aimed to extend the characteristics of OEP analysis to local analyses of thoraco-abdominal surface geometry and kinematics during respiration. Starting from the OEP output file, the 3D markers’ coordinates were combined with a triangulation matrix. A smoothing procedure (an automatic and iterative interpolation process to increase the number of vertices from 93 to 548) was applied to allow for precise local analysis of the thoraco-abdominal surface. A series of measurements can be performed to characterize the geometry of the trunk and its three compartments, in terms of volumes, height, diameters, perimeters, and area. Some shape factors, such as surface-to-volume ratio or height-to-perimeter ratio, can be also computed. It was also possible to build the vector field associated with the breathing motion of all the vertices, in terms of magnitude and motion direction. The vector field data were analyzed and displayed through two graphic tools: a 3D heatmap, in which the magnitude of motion was associated to different colors, and a 3D arrow plot, that allowed us to visualize both the magnitude and the direction of motion with color-coded arrows. The methods were applied to 10 healthy subjects (5 females) and also applied to two cases: a pregnant woman at each trimester of gestation and a patient before and after a demolition thoracic surgery. The results proved to be coherent with the physiology of healthy subjects and the physiopathology of the cases. We developed a new non-invasive method for respiratory analysis that allowed for the creation of realistic 3D models of the local and global trunk surface during respiration. The proposed representation constituted a very intuitive method to visualize and compare thoraco-abdominal surface movements within and between subjects, therefore enforcing the potential clinical translational value of the method

Lung and chest wall volume during vital capacity manoeuvre in Osteogenesis Imperfecta

Background: Although Osteogenesis Imperfecta (OI) affects the connective tissue, pulmonary function might be compromised because of thoracic deformities. OI is known to be a restrictive lung disease, but spirometry provides global measurement without localizing the site of the restriction. Opto-electronic plethysmography (OEP), is a non-invasive method able to underline altered respiratory function as well as ventilatory thoraco-abdominal paradoxes during spontaneous breathing. We aimed to reconstruct the thoraco-abdominal surface, to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics according to OI severity, particularly during maximal inspiratory and expiratory expansions. This is a cross-sectional study where we have studied the thoraco-abdominal compartmental analysis in 26 adult OI patients (14 Type III) at rest and during vital capacity manoeuvre using OEP. We have also applied a new method that created realistic and accurate 3D models to perform local analyses of trunk motion and to make quantitative comparison of trunk shape and respiratory kinematics. Results: Type III patients were characterized by lower spirometric lung volume, by lower sleep quality, by a more compressed thoracic configuration aggravated by severe scoliosis, by reduced global expansion at rest and during maximal maneuvers because of the reduced expansion of the pulmonary ribcage at rest (12% vs. 65% in healthy subjects), during maximal inspiration (37% vs. 69%) and expiration (16% vs. 68%) with local paradoxical movement occurring on the side of the ribcage region. Conclusion: The kinematics of the trunk changed to compensate for the severe structural deformities by shifting the expansion in the abdomen both at rest and during maximal manoeuvre because of a restricted thorax. For the first time, we have quantified and localized the site of the restriction in OI patients in the lateral part of the thorax. The 3D analysis proposed seemed a promising graphical immediate new method for pathophysiology study of chest wall restriction

Pulmonary and chest wall function in obese adults

Obesity is frequently associated with breathing disorders. To investigate if and how the highest levels of obesity impact respiratory function, 17 subjects with obesity (median age: 49 years; BMI: 39.7 kg/m2, 8 females) and 10 normal-weighted subjects (49 years; 23.9 kg/m2, 5 females) were studied. The abdominal volume occupied 41% in the obese group, being higher (p < 0.001) than the normal-weighted group (31%), indicating accumulation of abdominal fat. Restrictive lung defect was present in 17% of subjects with obesity. At rest in the supine position, subjects with obesity breathed with higher minute ventilation (11.9 L/min) and lower ribcage contribution (5.7%) than normal weighted subjects (7.5 L/min, p = 0.001 and 31.1%, p = 0.003, respectively), thus indicating thoracic restriction. Otherwise healthy obesity might not be characterized by a systematic restrictive lung pattern. Despite this, another sign of restriction could be poor thoracic expansion at rest in the supine position, resulting in increased ventilation. Class 3 obesity made respiratory rate further increased. Opto-electronic plethysmography and its thoraco-abdominal analysis of awake breathing add viable and interesting information in subjects with obesity that were complementary to pulmonary function tests. In addition, OEP is able to localize the restrictive effect of obesity

Extracorporeal membrane oxygenation: The simplified weaning bridge

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Protein differences among the Mediterranean species of the genus Spicara.

Protein electrophoresis (PAGE) was used to study the three morphologically different species of Spicara (S. flexuosa, S. maena, S. smaris). Of the 28 enzymatic and additional myogenic loci, five monomorphic loci (LDH-1*, G6PD-1*, PGI-1* and two PMMs*) were species-specific markers of S. smaris with respect to S. flexuosa and S. maena. Four of the 28 enzymatic loci were polymorphic (EST-1*, GLDH*, PEPD*, PGI-2*). Discriminating genetic markers were not identified between S. flexuosa and S. maena. Genetic distance (D) as calculated by Nei’s index (1978), between S. smaris v. S. maena and S. flexuosa showed a value, respectively of D=0·137 and 0·141. Between S. flexuosa and S. maena the value was D=0·006. From the data it can be inferred that S. flexuosa and S. maena are conspecific, despite morphological differences

Efficacy of lung volume optimization maneuver monitored by optoelectronic pletismography in the management of congenital diaphragmatic hernia

Newborns affected by congenital diaphragmatic hernia (CDH) need cardio-respiratory stabilization before undergoing surgical repair. Open lung strategy is a well-established approach to optimize lung volume in preterm infants with Respiratory Distress Syndrome (RDS), using both High Frequency Oscillatory Ventilation (HFOV) and Conventional Mechanical Ventilation (CMV). We report a case of left CDH with severe lung hypoplasia, managed applying open lung strategy in HFOV (pre-surgery period) and in Assist-Control with Volume Guarantee (post-surgery period), guided by SpO2changes, TcPO2and TcPCO2monitoring. Opto-electronic plethysmography was used to measure end-expiratory chest wall volume changes (ΔEEcw) related to lung volume variations occurring during pressure changes. OEP confirmed the efficacy of using SpO2and transcutaneous gas monitoring during this recruitment maneuver

Plio-Pleistocene geological evolution of the northern Sicily continental margin (southern Tyrrhenian Sea): new insights from high-resolution, multi-electrode sparker profiles

High-resolution seismic profiles were acquired in the north Sicily offshore region with an innovative, multi-tip sparker array which lacks ringing and has a base frequency around 600 Hz. The new data, combined with published data, suggest that intra-slope and extensional basins formed as a consequence of the late Miocene (?)–early Pliocene shortening and thrusting, and the middle (?)–late Pliocene continental rifting affecting the internal side of the Sicilian-Maghrebian chain. Early (?) Pleistocene to Holocene high-amplitude and high-frequency sea-level changes resulted in repeated sub-aerial exposure and flooding of the shelf, and the deposition of cyclically arranged hemipelagic and shelf sediments. An uplift of the shelf could explain the non-preservation of the transgressive and of the lowstand wedge systems tracts in the oldest sequences

Specific anion effects on urease activity: A Hofmeister study

: The effects of a range of electrolytes on the hydrolysis of urea by the enzyme urease is explored. The autocatalytic behavior of urease in unbuffered solutions and its pH clock reactions are studied. The concentration dependence of the experimental variables is analyzed in terms of specific ion-enzyme interactions and hydration. The results offer insights into the molecular mechanisms of the enzyme, and on the nature of its interactions with the electrolytes. We found that urease can tolerate mild electrolytes in its environment, while it is strongly inhibited by both strong kosmotropic and strong chaotropic anions. This study may cast light on an alternative therapy for Helicobacter pylori infections and contribute to the design of innovative materials and provide new approaches for the modulation of the enzymatic activity