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The polymer technology based on Electroactive polymers and metal composite ionic polymer has great potential and advantages in many engineering fields. In this paper, a laboratory stand for testing Ionic polymer-metal composites (IPMC) is presented. The laboratory station includes a power supply system and a measuring system for the displacement of IPMC composites. Tests and measurements are carried out using a laser transducer and a camera equipped with image analysis software to determine the IPMC strips displacement. The experimental investigation of IPMCs under different voltage supplies and waveforms, environmental working humidity conditions, temperature, and loading conditions has proved the significant influence of geometric dimension and the effect of increased stress on the displacement value. For materials powered by a higher voltage value, an increased deflection value was noted. In case of displacement, longer is the sample, higher is the displacement value. The length of the sample under load, affects adversely its performance, resulting in an increase in the load on the sample. For samples of a thick size, a more stable movement with and without load can be noticed.

In order to obtain optimized elementary devices (photovoltaic modules, power transistors for energy efficiency, high-efficiency sensors) it is necessary to increase the energy conversion efficiency of these devices. A very effective approach to achieving this goal is to increase the absorption of incident radiation. A promising strategy to increase this absorption is to use very thin regions of active material and trap photons near these surfaces. The most effective and cost-effective method of achieving such optical entrapment is the Raman scattering from excited nanoparticles at the plasmonic resonance. The field of plasmonics is the study of the exploitation of appropriate layers of metal nanoparticles to increase the intensity of radiation in the semiconductor by means of near-field effects produced by nanoparticles. In this paper, we focus on the use of metal nanoparticles as plasmonic nanosensors with extremely high sensitivity, even reaching single-molecule detection. The study conducted in this paper was used to optimize the performance of a prototype of a plasmonic photovoltaic cell made at the Institute for Microelectronics and Microsystems IMM of Catania, Italy. This prototype was based on a multilayer structure composed of the following layers: glass, AZO, metal and dielectric. In order to obtain good results, it is necessary to use geometries that orthogonalize the absorption of light, allowing better transport of the photocarriers-and therefore greater efficiency-or the use of less pure materials. For this reason, this study is focused on optimizing the geometries of these multilayer plasmonic structures. More specifically, in this paper, by means of a neurocomputing procedure and an electromagnetic fields analysis performed by the finite elements method (FEM), we established the relationship between the thicknesses of Aluminum-doped Zinc oxide (AZO), metal, dielectric and their main properties, characterizing the plasmonic propagation phenomena as the optimal wavelengths values at the main interfaces AZO/METAL and METAL/DIELECTRIC.

The paper presents research on a specific approach to the issue of computed tomography with an incomplete data set. The case of incomplete information is quite common, for example when examining objects of large size or difficult to access. Algorithms devoted to this type of problems can be used to detect anomalies in coal seams that pose a threat to the life of miners. The most dangerous example of such an anomaly may be a compressed gas tank, which expands rapidly during exploitation, at the same time ejecting rock fragments, which are a real threat to the working crew. The approach presented in the paper is an improvement of the previous idea, in which the detected objects were represented by sequences of points. These points represent rectangles, which were characterized by sequences of their parameters. This time, instead of sequences in the representation, there are sets of objects, which allow for the elimination of duplicates. As a result, the reconstruction is faster. The algorithm presented in the paper solves the inverse problem of finding the minimum of the objective function. Heuristic algorithms are suitable for solving this type of tasks. The following heuristic algorithms are described, tested and compared: Aquila Optimizer (AQ), Firefly Algorithm (FA), Whale Optimization Algorithm (WOA), Butterfly Optimization Algorithm (BOA) and Dynamic Butterfly Optimization Algorithm (DBOA). The research showed that the best algorithm for this type of problem turned out to be DBOA.

In recent times, many different types of systems have been based on fractional derivatives. Thanks to this type of derivatives, it is possible to model certain phenomena in a more precise and desirable way. This article presents a system consisting of a two-dimensional fractional differential equation with the Riemann-Liouville derivative with a numerical algorithm for its solution. The presented algorithm uses the alternating direction implicit method (ADIM). Further, the algorithm for solving the inverse problem consisting of the determination of unknown parameters of the model is also described. For this purpose, the objective function was minimized using the ant algorithm and the Hooke-Jeeves method. Inverse problems with fractional derivatives are important in many engineering applications, such as modeling the phenomenon of anomalous diffusion, designing electrical circuits with a supercapacitor, and application of fractional-order control theory. This paper presents a numerical example illustrating the effectiveness and accuracy of the described methods. The introduction of the example made possible a comparison of the methods of searching for the minimum of the objective function. The presented algorithms can be used as a tool for parameter training in artificial neural networks.

Efficient energy production from biomass is a central issue in the context of clean alternative energy resource. In this work we propose a novel model based on spiking neural networks cubes in order to model the chemical processes that goes on in a digestor for the production of usable biogas. For the implementation of the predictive structure, we have used the NeuCube computational framework. The goals of the proposed model were: develop a tool for real applications (low-cost and efficient), generalize the data when the system presents high sensitivity to small differences on the initial conditions, take in account the "multi-scale" temporal dynamics of the chemical processes occurring in the digestor, since the variations present in the early stages of the processes are very quick, whereas in the later stages are slower. By using the first ten days of observation the implemented system has been proven able to predict the evolution of the chemical process up to the 100th day obtaining a high degree of accuracy with respect to the experimental data measured in laboratory. This is due to the fact that the spiking neural networks have shown to be able to modeling complex information processes and then it has been shown that spiking neurons are able to handle patterns of activity that spans different time scales. Thanks to such properties, our system is able to capture the multi-scale trend of the time series associated to the early-stage evolutions, as well as their interaction, which are crucial in the point of view of the information content to obtain a good long-term prediction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this paper a novel training technique is proposed to offer an efficient solution for neural network training in non-trivial and critical applications such as the diagnosis of health threatening illness. The presented technique aims to enhance the generalization capability of a neural network while preserving its sensitivity and precision. The implemented method has been devised in order to slowly increase, during training, the generalization capabilities of a Radial Basis Probabilistic Neural Network classifier, as well as preventing it from over-generalization and the consequent lack of resulting classification performances. The developed method was tested on Electrocardiograms. These latter are generally considered non-trivial both due to the difficulty to recognize some anomalous heart activities, and due to the intermittent nature of abnormal beat occurrences. The implemented training method obtained satisfactory performances, sensitivity and precision while showing high generalization capabilities., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The paper proposes a new approach to heart activity diagnosis based on Gram polynomials and probabilistic neural networks (PNN). Heart disease recognition is based on the analysis of phonocardiogram (PCG) digital sequences. The PNN provides a powerful tool for proper classification of the input data set. The novelty of the proposed approach lies in a powerful feature extraction based on Gram polynomials and the Fourier transform. The proposed system presents good performance obtaining overall sensitivity of 93%, specificity of 91% and accuracy of 94%, using a public database of over 3000 heart beat sound recordings, classified as normal and abnormal heart sounds. Thus, it can be concluded that Gram polynomials and PNN prove to be a very efficient technique using the PCG signal for characterizing heart diseases., Competing Interests: The authors declare that there is no conflict of interest.This paper does not contain any studies with human participants or animals performed by any of the authors. On this matter we would also like to point out that our experiments, concerning data analysis and classification, has not directly been performed on human beings, but were concerning the off-line analysis of the signals obtained by a public database (see https://physionet.org/challenge/2016/) in order to grant more transparency and to use a safe data source also in terms of ethical approval.

Surface Plasmon Polaritons are collective oscillations of electrons occurring at the interface between a metal and a dielectric. The propagation phenomena in plasmonic nanostructures is not fully understood and the interdependence between propagation and metal thickness requires further investigation. We propose an ad-hoc neural network topology assisting the study of the said propagation when several parameters, such as wavelengths, propagation length and metal thickness are considered. This approach is novel and can be considered a first attempt at fully automating such a numerical computation. For the proposed neural network topology, an advanced training procedure has been devised in order to shun the possibility of accumulating errors. The provided results can be useful, e.g., to improve the efficiency of photocells, for photon harvesting, and for improving the accuracy of models for solid state devices.

We study phase synchronization in a network motif with a starlike structure in which the central node's (the hub's) frequency is strongly detuned against the other peripheral nodes. We find numerically and experimentally a regime of remote synchronization (RS), where the peripheral nodes form a phase synchronized cluster, while the hub remains free with its own dynamics and serves just as a transmitter for the other nodes. We explain the mechanism for this RS by the existence of a free amplitude and also show that systems with a fixed or constant amplitude, such as the classic Kuramoto phase oscillator, are not able to generate this phenomenon. Further, we derive an analytic expression which supports our explanation of the mechanism.

Some complex measures based on recurrence plots give evidence about hyperchaos-chaos transitions in coupled nonlinear systems [E. G. Souza et al., "Using recurrences to characterize the hyperchaos-chaos transition," Phys. Rev. E 78, 066206 (2008)]. In this paper, these measures are combined with a significance test based on twin surrogates to identify such a transition in a fourth-order Lorenz-like system, which is able to pass from a hyperchaotic to a chaotic behavior for increasing values of a single parameter. A circuit analog of the mathematical model has been designed and implemented and the robustness of the recurrence-based method on experimental data has been tested. In both the numerical and experimental cases, the combination of the recurrence measures and the significance test allows to clearly identify the hyperchaos-chaos transition., (© 2010 American Institute of Physics.)

Aim: Splenic injuries, like other blunt traumatic injuries, are very frequent, especially in case of traffic accident. The purpose of this study was to present the authors' experience of blunt splenic trauma and to compare it with the studies described in literature., Methods: Over a 5-year period 512 injured patients were admitted to the trauma center, 57 of whom presented splenic injuries, and they were retrospectively analyzed. Data review included demographic information, trauma mechanism, admitting hemodinamic parameters, Injury Severity Score. The patients were classified in two groups, one composed by immediate operated injured because their initially hemodinamic instability (27 patients) and another where patients underwent planned nonoperative management (29 patients), which included strict bed rest, frequent physical examinations, serial hematocrits and repeated diagnostic images. The patients were compared to find which factors influence the choice of surgical treatment., Results: There are statistically significant differences between the groups, concerning admitting hemodinamic parameters, as blood pressure and pulse rate, and the grade of anatomic splenic injury. Four patients failed nonsurgical management and required a splenectomy, because during the third day they suddenly presented clinical deterioration., Conclusions: Comparing these results with literature the authors try to improve spleen preserving program avoiding surgery when possible and using for example splenic embolization.

Crush injuries and crush syndrome are common after natural (e.g. earthquake, land-slide, tornadoes, tsunami) or man-made catastrophes (e.g. wars, terrorist attacks), in fact the history of this disease is well reported both in earthquake rescue reviews and in military literature. However, there are instances due to conventional causes, such as building collapses, road traffic accident, accident at work or altered level of consciousness after stroke or drug overdose. These situations of ''big or small'' catastrophes can occur at any time and anywhere, for this reason every clinician should be prepared to address issues of crush syndrome quickly and aggressively. The treatment has to manage and to predict clinical conditions before they present themselves. In particular, acute renal failure is one of the few life-threatening complications that can be reversed. This article reviews the various evidences and summarizes the treatment strategies available. Fundamental targets in crush syndrome management are early aggressive hydration, urine alkalinization and, when possible, forced diuresis. Since electrolyte imbalance may be fatal due to arrhythmias secondary to hyperkalemia (especially associated with hypocalcemia), it's necessary to correct these abnormalities using insulin-glucose solution and/or potassium binders, and if nevertheless serum potassium levels remain high this serious disease will necessitate dialysis, which is often a vital procedure.

We introduce a programmable electronic circuit implementing the rich dynamics of CO2 laser models. The design and the implementation of the circuit are accomplished by using a programmable analog device, which permits an experimental characterization of the laser dynamics. The experimental results shown in the paper demonstrate that the circuit exhibits homoclinic chaos typical of CO2 laser with feedback modulation of cavity losses. Moreover, experimental results showing that noise regularizes the dynamical time scales of the system are reported.

Despite advances in diagnosis, surgical treatment, antimicrobial therapy and intensive care support, severe secondary peritonitis remains a potentially fatal affliction. The purpose of this study is to present our experience of postoperative mortality in 255 patients with secondary acute peritonitis between 1998 to 2002. The Mannhein Peritonitis Index score (MPI) was calculated for each patient to predict the peritonitis related in-hospital death. Both literature reviews and our results show a strong correlation between some etiopathogenetic elements (age, origin of sepsis, organ failure, ...) and prognosis. Our patients were classified in three groups according to MPI, one with a score less than 21, another with a score between 21 and 29 and the third one with a score greater than 29. There was no mortality in the first group and there was significantly less mortality in the second group than the third one (P<0.001). While prognosis is influenced by many factors, the intervention time was the same, greater than 24 hours, for all the patients regardless of MPI score. This study suggests that intervention time may be considered the main determinant of mortality in patients with peritonitis. This observation is especially relevant since intervention time is a modifiable prognostic factor whilst many other factors are not.

Videoconferencing at 384 kbit/s for the transmission of echocardiograms has proved useful for the assessment of children with suspected cardiac disease, in regional areas of Queensland. A retrospective review of patient and management outcomes was conducted on cardiac teleconsultations performed at two regional hospitals during the period November 2000 to February 2004, inclusive. There were 106 echo studies. A subset of 72 cardiac teleconsultations performed between May 2001 and February 2004 was reviewed in detail. The median age of patients at the time of consultation was 3 months (range 1 day-17 years). Sixteen per cent of teleconsultations were classified as urgent and were conducted on the same day as referral. Following the videoconference, 90% of patients could be managed locally and reviewed by the paediatrician or visiting paediatric cardiologist during an outreach clinic. Six children (8%) had significant cardiac lesions that were initially managed locally, with subsequent elective transfer at the appropriate time for treatment. Only one child (1%) required urgent transfer to the tertiary centre for specialist care and surgery. Telecardiology was effective in accurately identifying congenital heart disease. Paediatric telecardiology is an evolving modality of assessment and communication, and is likely to result in continued improvements in patient care, patient outcomes and parental satisfaction, in provincial centres removed from the tertiary cardiac centre.

Obsessive compulsive disorder (OCD) often coexists with major depression (MD), with rates varying from 35 to 75%. The nature of the depressive symptomatology can be investigated by familial aggregation analysis, assuming that the disorder which occurs first is the one showing greater genetic liability and should have higher familial concentration. Therefore, the aim of our study was to assess the familial loading for OCD and mood disorders in the families of OCD patients with different chronology of onset for the mood disorder, to evaluate how the familial pattern of the diseases differs with different temporal sequences in which the two syndromes occur. A total of 172 OCD patients entered the study; 112 were pure OCD probands, 12 were unable to separate the onset of the two syndromes, 11 had prior mood disorder, and 37 of them had experienced their first depressive episodes after the onset of OCD. Information about the family history was collected by means of the Family History-Research Diagnostic Criteria (FH-RDC) and by directly interviewing at least 2 relatives per family. Morbidity risks for OCD indicate a familial concentration of the disorder in all groups, except the MD/OCD group. We found the highest rate of relatives affected by mood disorders in the families of patients with first onset of MD (28.8%), whereas in the other 3 groups MRs were much lower. These results suggest the affective nature of OCD patients who experienced first onset of MD. Thus, the chronology of onset seems to identify 2 different typologies of familial distribution.

Controversial results possibly suggesting an association between Tourette's Syndrome (TS) and excess of homozygosity at a Msc I polymorphism in the Dopamine D3 receptor (DRD3) gene have recently been reported. Since a relationship between Obsessive-Compulsive Disorder (OCD) and Tourette's Syndrome (TS) has been suggested, in this study we assessed the frequency of this 2-allele polymorphism in a sample of 97 OCD patients and in 97 control subjects. No statistically significant differences in allele or genotype frequencies were found. Thus this mutation in the coding sequence of the DRD3 gene is unlikely to confer susceptibility to OCD.

Some studies suggest a relationship between obsessive-compulsive disorder (OCD) and Gilles de la Tourette's syndrome. The pathophysiology of the latter may involve the dopamine system. We screened three important exons of the dopamine D2 receptor (DRD2) gene for mutations in a group of OCD patients with or without tics. No structural changes were found, suggesting no relationship between DRD2 and OCD. Moreover, the frequency of the polymorphism in exon 6 was different from that found in schizophrenics.

The rate of comorbid diagnoses in a group of 92 patients with obsessive-compulsive disorder (OCD) was examined, with particular attention being paid to mood disorders. The family history method was used to study the frequency of psychiatric disorders in the patients' families and to analyze the characteristics of the familial loading for OCD and mood disorders. A comorbid diagnosis of mood disorder occurred in 35.9% of the patients. The morbidity risk for OCD in the patients' families accounted for 3.4%; when 21 patients with an age of onset under 14 were examined, the morbidity risk in first degree relatives reached 8.8%. This tendency did not appear to be true for mood disorders.

Immunological, neuroendocrine and psychological parameters were examined in 14 psychophysically healthy subjects and in 17 panic disorder patients before and after a 30-day course of alprazolam therapy. T lymphocyte proliferation in response to the mitogen phytohemagglutinin, lymphocyte beta-endorphin (beta-EP) concentrations, plasma ACTH, cortisol and beta-EP levels were examined in basal conditions and after corticotropin-releasing hormone (CRH) stimulation. Cortisol inhibition by dexamethasone (DST) and basal growth hormone (GH) and prolactin levels were also examined. Depression, state or trait anxiety, anticipatory anxiety, agoraphobia, simple and social phobias, severity and frequency of panic attacks were monitored by rating scales. The immune study did not reveal any significant difference between patients and controls, or any effect of alprazolam therapy. The hormonal data for the two groups were similar, except for higher than normal basal ACTH and GH plasma levels, lower than normal ratios between the ACTH and cortisol responses to CRH, and blunted DST in some patients. All the impairments improved after alprazolam therapy, in parallel with decreases in anxiety and in severity and frequency of panic attacks.

Forty-eight patients with panic disorder/agoraphobia (PAD) and 30 with obsessive-compulsive disorder (OCD) were assessed for DSM-III-R axis II personality disorders (PD) and the presence of the same anxiety disorder in the relatives of probands (homotypic disorders). No specific personality disorder was present significantly more often in either of the two groups. Agoraphobia was not associated with higher rates of axis II disorders in PAD patients. Duration of illness did not influence the presence of a PD in patients of both groups. Secondary cases of the same anxiety disorder were significantly more common among first-degree relatives of PAD patients. A discriminant analysis performed on the most frequent personality traits of both groups provided a correct classification of cases of 97.4%. Our results do not support the hypothesis of PD as secondary to anxiety disorders and confirm previous findings of a lack of specificity between DSM-III-R axis II categories and OCD and PAD.

Clinical problems to consider in excessive obesity are numerous. Careful preparation before surgery is indispensable to reduce complications during and after surgery. Choice of volatile anesthetic may be important for the good results of narcosis. In the reported case anesthetic management is considered in an obese patient who had undergone a gastric operation.

We analyzed the familial morbidity risk for mood disorders (MR) and the presence of a family history of alcoholism in a group of 58 patients with DSM-III borderline personality disorder (PD). The MR in the families of borderline subjects was not significantly different from that found in a control group of affective patients with other cluster II PD, or without PD. The MR in the families of borderline subjects who had never developed an affective episode was not significantly different from that found in the families of borderline PD with a history of mood disorders. Borderline subjects with mood disorders had higher rates of alcoholism in their families, mainly among parents. Our results support the hypothesis that borderline PD, even in absence of the codiagnosis of a mood disorder in the subject, may be a predictor of higher familial liability to mood disorders, although it may be more informative for the familial clustering of specific subgroups than for mood disorders as a whole.

In a study of the families of 21 schizotypal patients, we found an increased morbidity risk for schizophrenia compared with that in the families of 21 nonschizotypal patients and 42 controls. The Axis I diagnoses did not influence the distribution of the morbidity risk in the families of the schizotypal patients. If the schizotypal subjects also had other personality disorders, the morbidity risk for schizophrenia among their relatives was lower, although not significantly.

Two patients with retroperitoneal liposarcoma are presented to determine the accuracy of diagnostic methods and the role of surgical treatment. In both the patients the large retroperitoneal liposarcoma recurred locally after surgery. Histological features, clinical presentation, diagnostic procedures, extent of surgical resection and adjuvant treatment are reviewed. These data suggest that an aggressive surgical approach followed by adjuvant postoperative irradiation is the treatment of choice in primary and recurrent neoplasms.

Aluminium (Al) overload has been recognised as a frequent complication in uraemic patients on regular dialysis treatment. We report how acute visual disorders occurred after performing a desferrioxamine (DFO) test in patients on regular dialysis treatment suspected of having aluminium overload. Fifteen patients on regular dialysis treatment for 132 +/- 73 (range 17-250) months, aged 61 +/- 10 (range 47-79) years were given DFO as a test at standard dosage. In the 13 patients who complained of visual disorders, we performed ophthalmologic examinations soon after DFO administration, and again 5 months later in 11 of them. A decrease in visual acuity and/or dyschromatopsia, transient or permanent, were present in ten patients. Four had permanent maculopathy and three also had a permanent alteration of VEP (visual evoked potential). Visual fields were normal in all patients except one who presented a permanent central scotoma. The EOG (electro-oculogram) was permanently impaired in five patients and some of them had fluoroangiographic alterations due to damage of the pigmented epithelium. Six to eight months after the DFO test four patients still complained of visual acuity reduction. We conclude that there is a high rate of visual disorders after giving DFO at the standard doses; therefore we stress the need to modify the doses commonly used and/or the mode of infusion.

The authors report a case they had the opportunity to observe, surgically treated (thoraco-phrenotomy, removal of the herniated mass, repair of the diaphragmatic breach). They illustrate the genesis of such abnormality, its incidence and symptomatology. The Authors, moreover, dwell upon the diagnostic problems caused by Bochdalek's hernia with retroperitoneal contents, and upon the advantages shown by the thoracic way of aggression in the light of their own experience.

The authors, showing a case of breast retroareolar leiomyoma, study the literature thereabout, and emphasize the rareness of such disease, the impossibility of a correct preoperative diagnosis and the features of absolute benignity of this lesion.

One case of small bowel obstruction due to phytobezoar is reported. The various aetiological factors are discussed. The clinical features are not typical and small bowel obstruction can be initially recurrent until a complete intestinal occlusion. The diagnosis is not easy, and is nearly always made during urgent laparotomy. Surgical treatment consists of phytobezoar removal by enterotomy. The recognition of high-risk patients and their education to prevent phytobezoar are emphasized.