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Switch-mode power supplies (SMPS) generate distorted nonsinusoidal current waveforms flowing into conductors (wires, striplines, windings), which cause ohmic losses mainly ruled by the skin-effect. Skin effect is traditionally studied in the frequency domain; most studies on the effects of distorted SMPS current waveform are devoted to examine the so-called high-frequency effects, namely the behavior of components and systems at the switching frequency and its harmonics, considering a virtual sinusoidal steady-state operation at each frequency of the range under study. In this paper skin-effect has been studied in the time-domain by means of a formulation based on a magnetic vector potential A and on a scalar potential p. The obtained results show that the equivalent per-unit length resistance of conductors carrying typical SMPS nonsinusoidal current waveforms depend both on switching frequency and duty-cycle and is rather different from DC and AC sinusoidal equivalent resistances.

Peri-implant soft tissues play a role of paramount importance, not only on the esthetic appearance, but also on the maintenance and long-term stability of implants. The present report presents the conclusions from the Consensus Conference of the South European North African Middle Eastern Implantology & Modern Dentistry Association (SENAME) (4–6 November 2016, Cairo, Egypt). The conference focused on the topic of the soft tissue around dental implants, and in particular, on the influence of implant configurations on the marginal soft tissues, soft tissue alterations after immediate, early or delayed implant placement and immediate loading, the long-term outcomes of soft tissue stability around dental implants, and soft tissue augmentation around dental implants. Thirty world experts in this field were invited to take part in this two-day event; however, only 29 experts were in the final consensus voting process.

The present study aimed to investigate the correlation between chronological age and pulp–tooth volume ratio in anterior teeth using cone beam computed tomographic (CBCT) images and provide equations for age estimation based on pulp–tooth volume ratio. In this cross-sectional study, CBCT images of 312 anterior teeth of the maxilla and mandible were examineαd. The chronological age and the sex of the patients were recorded. Tooth volume and pulp volume of the anterior teeth were measured using Mimics software, and then tooth–pulp volume ratio was calculated. Statistical analysis of data was performed using chi-square test, independent T-test, Pearson’s correlation, and linear regression (α = 0.05). Finally, equations were made based on the results of the regression analysis for age estimation in general and for males and females. The age of the subjects ranged between 16 and 69 years (mean 40.6 ± 12.74). The pulp–tooth volume ratio of the maxillary teeth was generally higher than the mandibular teeth. A significant inverse relationship between age and pulp–tooth volume ratio was observed for all anterior teeth. (p &lt, 0.05). The strongest correlation between age and pulp–tooth volume ratio was reported for mandibular central incisor (r = −0.58, p &lt, 0.001) and the weakest was for mandibular lateral incisor (r = −0.36, p = 0.012). Age estimation was most accurate among females using the maxillary central incisors (p &lt, 0.001) and among males using the mandibular central incisors and maxillary canines (p = 0.003). Pulp–tooth volume ratio of mandibular central incisors, maxillary lateral incisors, and maxillary canines in males and maxillary and mandibular central incisors, maxillary lateral incisors, and maxillary and mandibular canines in females can be used for age estimation.

Researchers have always been interested in finding new and effective materials for protection against radiation. This experimental study aimed to design and fabricate new types of nano-material and micro-material based shields against the ionizing effect of cone beam computed tomography (CBCT) X-rays. To fabricate a flexible prototype, we added dioctyl phthalate (DOP) oil to emulsion polyvinyl chloride (PVC) powder. The paste was mixed and dispersed. Then, nano- and micro-powders of WO3 and Bi2O3 were added to the paste, with the weight ratio of 20% PVC, 20% DOP, and 60% nano- and micro-metals. Using an ultrasonic mixer, the polymer matrix and metals were mixed and a paste with a thick texture was developed. The resultant paste was poured into glass molds and the molds were then heated in an oven. After cooling, the resultant sheets were selected for further experiments. A CBCT unit and dosimeter were used to evaluate the characterization and X-ray shielding properties of the fabricated prototypes. The half-value layers (HVL) for nano-WO3, micro-WO3, nano-Bi2O3, and micro-Bi2O3 were 0.0390, 0.0524, 0.0351, and 0.0374 cm, respectively. In addition, the linear attenuation coefficient (&micro, ) for these materials were 17.77, 13.20, 19.71, and 18.5 cm&minus, 1, respectively. The findings indicate that nano-structured samples are more effective in the attenuation of X-ray energy. The nano-structured WO3 prototype was nearly 34% more efficient in attenuating radiation compared to the micro-structured WO3 prototype. This difference in nano- and micro-structured Bi2O3 prototypes was 6.5%.

Background and Purpose. Following the new directives of the European Union, which foresee the amalgam ban, the debate on its hypothetical toxicity has started again. So, the aim of this systematic review is to definitively evaluate the eventual effects of the exposure to Hg in adults and children with and without dental amalgam fillings measuring the Hg concentration in various biological fluids.Methods. A systematic literature search was conducted in four electronic databases (Ovid via PubMed, Web of Science, Scopus, and CENTRAL) including all available randomised controlled trials published in the last 15 years comparing the use of dental amalgam with composite resins in humans with a follow-up period of at least one year. The primary outcome was the Hg concentration in biological fluids (urine, hair, blood, and saliva) with the aim of assessing their reliability as biomarkers of Hg exposure. The risk of bias was assessed through the Cochrane Collaboration tool and the overall quality of evidence through the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system. The results of the meta-analysis were expressed using a random-effects model, and their power was assessed through the trial sequential analysis (TSA).Results. From the initial 2555 results, only 6 publications were included in the review: five were considered as having high risk of bias, whereas one as having moderate risk. Only two articles were eligible for quantitative analysis. The meta-analysis gathered data from 859 patients but was nevertheless not significant (p = 0.12). The TSA confirmed this evidence revealing that it was due to a lack of statistical power since the required information size (RIS) threshold is not reached.Conclusions. The existing evidence revealed that there are not enough data to support the hypothesis that restorations with dental amalgam can cause nephrotoxicity when compared with composite resins restorations.

Coronavirus disease 2019, also called COVID-19, is the latest infectious disease to rapidly develop worldwide [...]

Introduction Dentistry, therefore implantology, prosthetics, implant prosthetics or orthodontics in all their variants, are medical and rehabilitative branches that have benefited greatly from these methods of investigation to improve the predictability of rehabilitations. We will examine the Finite Element Method and Finite Element Analysis in detail. This method involves the simulation of mechanical forces from an environment with infinite elements, the real one, to a simulation with finite elements. Evidence acquisition The study searched MEDLINE databases from 2008 to 2018. Human use of FEM in vitro studies reported a contribution on oral rehabilitation through the use of FEM analysis. The initial search obtained 296 citations. After a first screening, the present revision considered the English-language works referred to human application of the FEM published in the last 10 years. Finally, 34 full texts were available after screening. Evidence synthesis The ultimate aim of this review is to point out all the progress made in the field of bioengineering and therefore, thanks to this, in the field of medicine. Instrumental investigations such as FEM are an excellent tool that allows the evaluation of anatomical structures and any facilities for rehabilitation before moving on to experimentation on animals, so as to have mechanical characteristics and satisfactory load cycle testing. Conclusions FEM analysis contributes substantially to the development of new technologies and new materials in the biomedical field, being able to perform a large number of simulations without the need for patients or to perform human tests. Thanks to the 3D technology and to the reconstructions of both the anatomical structures and eventually the alloplastic structures used in the rehabilitations it is possible to consider all the mechanical characteristics, so that they can be analyzed in detail and improved where necessary. It is possible thanks to these methods to know what are the ideal characteristics of a material to promote an oral rehabilitation, so we know the characteristics, it remains only to take a step in the field of the industry for the construction of materials close to these characteristics.

This paper describes the contribution given by the application of the systems engineering approach to the European DEMO Breeding Blanket (BB) integration studies, focussing on the integration of Heating & Current Drive (H&CD) and Fuelling Lines (FL) systems. In particular, attention has been paid to the BB-H&CD and BB-FL interfaces identification, definition and capture of the proper interface requirements necessary to drive the integration process and, as a consequence, supply a feedback for the reciprocal design of the interconnected systems. The defined interfaces are synthetically described in the paper and the results of the interface requirements capture process are shown, discussing in detail the rationales behind the interface requirements definition. The implications of the selected interface requirements on the selection of the proposed H&CD and FL systems design options have been highlighted as well. Lastly, the open issues are discussed as well as the influence of the interface management process on the prosecution of the BB, H&CD and FL design activities.

The current study was conducted to assess the extent of maxillary arch collapse on the cleft vis-a-vis non-cleft sides in the same individual presenting withunilateral cleft lip and palate (UCLP), using cone-beam computed tomography (CBCT). Thirty-one children (eighteen boys andthirteen girls) with surgically repaired UCLP, who met the inclusion criteria, were selected. Following the acquisition of CBCT scans, fourteen bilateral landmarks were selected. The distance of the bilateral landmark was calculated from the midsagittal plane on the cleft and non-cleft sides for both frontal and axial views. Tracings were done;the data obtained was subjected to statistical analysis;and intra-observer variability was checked with intraclass correlation coefficient (ICC) and two-way ANOVA. Subsequently, the measurements were subjected to paired t-tests at the 95% level of significance with Bonferroni correction. A significant reduction of pyriforme and an alveolar crest above the maxillary 1st molar were discerned in frontal analysis on the cleft side. In the axial view, the zygomatic arch, malar, porion and alveolar crest at the molar region were non-significant, but the alveolar crest at the premolar region (p < 0.004)) was significantly decreased. In the frontal analysis, pyriforme and the alveolar crest above the maxillary 1st molar, and, in the axial view, premolar widths, showed significant reduction when comparing the cleft vis-a-vis non-cleft sides.

Mucous membrane pemphigoid (MMP) is a heterogeneous group of rare, systemic, autoimmune subepidermal inflammatory disease that affects mucous membranes and the eye. In its most severe forms, this disease needs systemic therapy, usually based on steroids and immunosuppressant agents. In unresponsive cases or in the presence of contraindications or severe side effects due to conventional systemic corticosteroid and/or immunosuppressant therapy, a therapy shift to high-dose intravenous immunoglobulins (IVIg) has been recommended in other reports. This new therapy has proven to be effective in stopping ocular pemphigoid, but the data regarding the long-term effect on the disease activity or reactivation are extremely scarce, so the novel scientific aim of this study was to evaluate the clinical outcomes after a 9-year follow-up in 12 eyes (6 patients) affected by MMP with ocular involvement, successfully treated with IVIg therapy, as previously described in our report published in 2008. The evaluation of ocular and extraocular disease progression was performed at the end of IVIg therapy and at the end of the follow-up period. After 9 years, all the eyes enrolled showed a long-lasting remission of ocular and oral symptoms with a significant steroid-sparing effect. In conclusion, the IVIg has to be considered as a safe and successful alternative therapy in patients with severe ocular mucous membrane pemphigoid; furthermore, this kind of therapy seems to be effective in maintaining the clinical remission by the time.

Objective: Aim of the study was to determined by microcomputed tomography (µCT) the horizontal distance between the main (MB1) and the second mesiobuccal canal (MB2) orifices, the vertical distance between the MB1 and MB2 orifices planes, and the distance between the anatomic apex and major apical foramen (AF). Furthermore, we characterized the entire internal and external anatomy of the MB, distalbuccal (DB) and palatal (P) maxillary first molars roots. Materials and Methods: Twenty-two intact extracted first maxillary molars were scanned by X-ray computed transaxial µCT and then 2D and 3D images were processed and analyzed. Results: The results showed that 77.27% of the mesiobuccal (MB) roots presented a second MB canal, and 29.41% of the MB2 were independent from the MB1 canals. In 15 teeth, there were three root canal orifices on the chamber floor, and 10 of these teeth presented MB2 canals. The mean vertical distance between the MB1 and MB2 planes was 1.68 ± 0.83 mm. Seven teeth had four orifices. The mean horizontal interorificial distance between the MB1 and MB2 orifices was 1.21 ± 0.5 mm. Accessory canals were observed in 33.33% of the roots, loops in 6.06%, while isthmuses were found in 15 of the 22 MB roots. Of the total roots, 74.24% presented one foramen, while all of the roots showed a major apical foramen that was not coincident with the anatomic apex. Conclusions: Our µCT analysis provided interesting features on the horizontal and vertical distance between the MB1 and MB2 orifices and on the distance of AF and anatomic apex. Clinical Relevance: These results have an important clinical value because might support the endodontist in the recruitment, negotiation and obturation of maxillary first molar canal system.

The American Association for the Study of Liver Diseases guidelines recommend the use of all available markers for improving the accuracy of the diagnosis of small hepatocellular carcinoma (HCC). To determine whether clathrin heavy chain (CHC), a novel HCC marker, is effective in combination with glypican 3 (GPC3), heat shock protein 70, and glutamine synthetase, we compared the performances of a three-marker panel (without CHC) and a four-marker panel (with CHC) in a series of small HCCs (≤2 cm) and nonsmall HCCs by core biopsy with a 20- to 21-gauge needle. The series included 39 nonsmall HCCs and 47 small HCCs (86 in all); the latter showed a well-differentiated histology [small grade 1 (G1)] in 30 cases (63.8%). The panel specificity was analyzed with the adjacent/extranodular cirrhotic liver (n = 30) and low-grade (n = 15) and high-grade dysplastic nodules (n = 16) as a control group. Absolute specificity (100%) for HCC was obtained only when at least two of the markers were positive (which two markers were positive did not matter). The addition of CHC to the panel increased the diagnostic accuracy for small HCCs (from 76.9% to 84.3%), and there was an important gain in sensitivity (from 46.8% to 63.8%). The four-marker panel had lower rates of accuracy (67.4%) and sensitivity (50%) for small G1 HCCs versus nonsmall G1 HCCs (93.9% and 88.2%, respectively). In seven cases (including six small G1 HCCs), there was no staining with any of the markers. Cirrhotic control livers were stained for CHC in four cases (13.3%) and for GPC3 in one case (3.3%). Conclusion: The addition of CHC to the panel supports the diagnosis of small HCCs in challenging nodules on thin core biopsy samples. Small G1 HCCs include a group of earlier tumors characterized by a more silent phenotype and the progressive acquisition of the markers under study. The search for additional markers for early HCC diagnosis is warranted. © 2011 American Association for the Study of Liver Diseases

Background & Aims Sorafenib is the standard of care in advanced hepatocellular carcinoma (HCC), however no criteria have been established to select patients likely to benefit from this therapy. In this study, we evaluated the predictive role of microRNAs (miRNAs) in this setting of patients. Methods We profiled 522 miRNA in a series of 26 HCC patients treated with sorafenib (training set) and validated the results in an independent series of 58 patients (validation set). Formalin-fixed paraffin-embedded tumour and cirrhotic liver biopsies were used for RNA extraction and miRNAs profiling with TaqMan Arrays technology. Statistical analyses were used to correlate miRNA levels with clinical outcome, including time to progression (TTP), progression free (PFS), and overall survival. Cell viability and cell motility of HuH-7 or HepG2 HCC cells were tested in vitro after transfection with specific miRNA precursor, inhibitor or controls and sorafenib treatment. Results Six miRNAs were significantly associated with clinical variables in the training set and only miR-425-3p could be further validated. Higher levels of miR-425-3p were associated with longer TTP and PFS (P = 0.0008; HR = 0.4; 95% CI = 0.2–0.7 and P = 0.007; HR = 0.5; 95% CI = 0.3–0.9 respectively). Multivariate analysis confirmed the predictive significance of miR-425-3p. Furthermore, an association between increased miR-425-3p, cell death and reduced cell motility was defined in vitro in HCC cell lines treated with sorafenib. Conclusions Assessment of miR-425-3p levels in liver biopsies could help in stratifying patients with advanced HCC for sorafenib treatment. These promising results need to be confirmed in a large prospective study.

A case of implant-bone prosthetic rehabilitation, after the fracture of the maxillary central incisors, which had been treated with grafting of a bone substitute, is reported. This case was followed by the normal procedures of implantology within the traditional timeframe for bone regeneration. However, a barrier membrane was not used which shows that even along with the use of graft material a sufficient amount of bone could be achieved for a subsequent rehabilitation. Therefore, after a five-year follow-up period, osseointegration was maintained with no marginal bone loss.

This paper describes the orthodontic treatment, and the biomechanics of cantilevers for the impaction of permanent teeth in youngs, adolescents, and adults. In these case series, multibracket straightwire fixed appliances, together with cantilever mechanics, were used to treat the impaired occlusion.

We report the results over 15 years (1977-1991) for biochemical diagnoses of patients referred from throughout Italy and suspected of having a mucopolysaccharidosis. Of these, 147 patients were diagnosed as being homozygous or hemizygous for a specific lysosomal enzyme deficiency; 74 pregnancies at risk were monitored in their families; 76 heterozygote diagnoses were performed on their relatives, with a total of 48 positive diagnoses. We also report the analysis of genomic DNA from 11 unrelated Italian Hunter patients, using pc2S15 probe. DNA from two patients, digested with Pst-I, showed a variant pattern of hybridization caused by deletion or rearrangement of the gene. © 1993 Society for the Study of Inborn Errors of Metabolism and Kluwer Academic Publishers.

One of the major drawbacks of photovoltaic (PV) systems is represented by the effect of module mismatching and of partial shading of the PV field. Distributed maximum power point tracking (DMPPT) is a very promising technique that allows the increase of efficiency and reliability of such systems. Modeling and designing a PV system with DMPPT is remarkably more complex than implementing a standard MPPT technique. In this paper, a DMPPT system for PV arrays is proposed and analyzed. A dc and small-signal ac model is derived to analyze steady-state behavior, as well as dynamics and stability, of the whole system. Finally, simulation results are reported and discussed.

For many years,maxillary width discrepancies have been corrected inpediatric patients solely by orthodontic therapies,such as slow orthodontic expansion (SOE) and rapidpalatal expansion (RPE), and in adult patients by sur-gical treatments such as surgically assisted rapid pal-atal expansion (SARPE) and 2-segment Le Fort I-typeosteotomy with expansion (LFI-E).

In recent years much interest is grown about the possibility to apply novel software technologies (such as those ones coming from Artificial Intelligence) to the field of Scientific Calculus. There is an increasing need of such approaches due to the hard requests for integration-cooperation features in modern applications, whose simulation tasks are asked to go far beyond the mere and rigid application of presumed general purpose numerical methods. In this paper we explore the use of Software Agents for Circuit-CAD (CCAD) with uncertainties handling capabilities. In such a field, solving some hard problems, like Tolerance and Sensitivity Analysis (TSA) for strongly non-linear circuits in presence of large parameters' uncertainties, benefits much more from a clever preliminary choice of the best problem-tuned numerical method rather than from a blind number crunching approach. Software Agents seem to meet these constraints while introducing a high degree of flexibility, which enables the implementation of dynamic adaptive resolution schemes for given CCAD tasks. We present an example of use of the proposed architecture utilizing Java to specify agents as active objects. Some applications of the new strategy to TSA circuits-related problems are presented.

Aims: Tissue transglutaminase (tTG) was recently identified as the major autoantigen in coeliac disease. The aim of this multicentre study was to evaluate the impact of a new immunoenzymatic assay for the detection of IgA anti-tGT antibodies. Methods: Seventy four Italian and French clinical laboratories participated in this study; anti-tTG IgA with an enzyme linked immunosorbent assay (ELISA) method using guinea pig liver extract as the coating antigen, anti-endomysium IgA autoantibodies (EMA), and total serum IgA were determined in 7948 patients, 1162 of whom had coeliac disease (737 untreated cases and 425 on a gluten free diet). A proportion of the sera were then sent to a reference laboratory for anti-tTG retesting with an ELISA method using recombinant human tTG antigen. Results: Seven thousand four hundred and fifty eight (93.8%) sera were EMA/antiguinea pig tTG concordant (positive or negative); 490 (6.2%) were non-concordant. The sensitivity of EMA and antiguinea pig tTG in the 737 untreated patients with coeliac disease was 92.1% and 94.8%, respectively, and the specificity was 99.8% and 99.2%, respectively. Retesting of the discordant sera showed that of the 162 sera classified as EMA negative/antiguinea pig tTG positive, only 49 were positive for human recombinant anti-tTG, and that 39 of these were also EMA positive. Furthermore, of the 36 sera classified as EMA positive/antiguinea pig tTG negative, only two were confirmed as EMA positive. Conclusions: The antiguinea pig tTG assay is more sensitive but less specific than EMA, whereas the antihuman recombinant tTG assay is far more specific and just as sensitive as antiguinea pig tTG. Testing for EMA presents considerable interpretative problems and is difficult to standardise.

In this paper a methodological study is presented for the optimal design of a vacuum feedthrough to be used in HV direct current, with high electrical performances in terms of holdoff voltage. From general guidelines, widely described in the literature and relevant to simpler geometric configurations, summarized in few basic rules useful to design vacuum insulators, the authors have sketched an optimal insulator profile for a cylindrical axisymmetrical arrangement. The adopted assumptions have been validated by means of numerical tools based on the charge simulation method and the finite difference method. A prototype feedthrough has been realised, matching the constraints about the field distribution achieved theoretically with technological constraints due to the manufacturing process. High voltage experimental tests confirming the effectiveness of the suggested insulator design approach are reported.

The work was designed to study the effects of a meat meal on glomerular filtration rate (GFR), renal plasma flow (RPF), and plasma concentrations of glucagon, insulin, growth hormone, renin, aldoster-one, total amino acids, and NH3 in healthy humans (H) as well as in patients with Child A liver cirrhosis (LC). The meat meal produced renal hyperaemia and hyperfiltration without changes in the filtration fraction. Fractional Na excretion in urine increased significantly after the meat meal only in LC. Hyperinsulinae-mia and hyperglucagonaemia were seen at baseline in LC and were not affected by the meat meal, whereas in H glucagon concentration increased significantly over baseline within 30 min from the meat meal and insulin within 60 min. Growth hormone concentration was normal at baseline in LC and increased significantly 120–180 min after the meal, whereas it was not affected in H. Renin and aldosterone were stable in both H and LC. Plasma amino acid concentration began to increase 60 min after the meat meal, when hyperfiltration was present. The data indicate that in human Child A cirrhosis of the liver the renal haemodynamic response to a meat meal is independent of changes in glucagon.

The exposition of HV solid insulators in a vacuum to relevant voltage differences could determine the surface flashover along the solid dielectric-vacuum interface. Insulator holdoff capabilities can be significantly improved by limiting the field intensity in proximity of the electrodes by means of geometrical field control, namely designing the insulator profile so that the region subjected to high field is shifted away from the regions where the electrodes join the solid dielectric-vacuum interface. In this paper, a new profile for an HV insulator in a vacuum is presented. An axially symmetrical configuration constituted by a couple of coaxial cylindrical electrodes is considered, with the insulator shape designed to guarantee similar performances for both field polarities. The effectiveness of the design is validated by means of numerical simulations and by experimental results involving DC and impulse flashover performances.