Neural networks in geophysical applications

Neural networks are increasingly popular in geophysics. Because they are universal approximators, these tools can approximate any continuous function with an arbitrary precision. Hence, they may yield important contributions to finding solutions to a variety of geophysical applications. However, knowledge of many methods and techniques recently developed to increase the performance and to facilitate the use of neural networks does not seem to be widespread in the geophysical community. Therefore, the power of these tools has not yet been explored to their full extent. In this paper, techniques are described for faster training, better overall performance, i.e., generalization,and the automatic estimation of network size and architecture

Delayed eruption of permanent dentition and maxillary contraction in patients with cleidocranial dysplasia: review and report of a family

Introduction. Cleidocranial dysplasia (CCD) is an inherited disease caused by mutations in the RUNX2 gene on chromosome 6p21. This pathology, autosomal dominant or caused by a spontaneous genetic mutation, is present in one in one million individuals, with complete penetrance and widely variable expressivity. Aim. To identify the incidence of these clinical findings in the report of the literature by means of PubMed interface from 2002 to 2015, with the related keywords. The report of local patients presents a clinical example, related to the therapeutic approach. Results and Discussions. The PubMed research resulted in 122 articles. All the typical signs were reported in all presented cases. The maxilla was hypoplastic in 94% of the patients. Missing of permanent teeth was found in two cases: one case presented a class II jaw relationship, instead of class III malocclusion. Similar findings were present in our cohort. Conclusion. CCD is challenging for both the dental team and the patient. The treatment requires a multidisciplinary approach. Further studies are required to better understand the cause of this disease. According to this review, a multistep approach enhances the possibilities to achieve the recovery of the most possible number of teeth, as such to obtain a good occlusion and a better aesthetic

Properties of galaxy halos in Clusters and Voids

We use the results of a high resolution N-body simulation to investigate the role of the environment on the formation and evolution of galaxy-sized halos. Starting from a set of constrained initial conditions, we have produced a final configuration hosting a double cluster in one octant and a large void extending over two octants of the simulation box. We present results for two statistics: the relationship between 1-D velocity dispersion and mass and the probability distribution of the spin parameter $P(\lambda)$. The \svm relationship is well reproduced by the Truncated Isothermal Sphere (TIS) model introduced by Shapiro et al. (1999), although the slope is different from the original prediction. A series of \svm relationships for different values of the anisotropy parameter $\beta$, obtained using the theoretical predictions by Lokas and Mamon (2001) for NFW density profiles are found to be only marginally consistent with the data. Using some properties of the equilibrium TIS models, we construct subsamples of {\em fiducial} equilibrium TIS halos from each of the three subregions, and we study their properties. For these halos, we do find an environmental dependence of their properties, in particular of the spin parameter distribution $P(\lambda)$. We study in more detail the TIS model, and we find new relationships between the truncation radius and other structural parameters. No gravitationally bound halo is found having a radius larger than the critical value for gravithermal instability for TIS halos (\rt $\ge 34.2 r_{0}$, where $r_{0}$ is the core radius of the TIS solution). We do however find a dependence of this relationship on the environment, like for the $P(\lambda)$ statistics. These facts hint at a possible r\^{o}le of tidal fields at determining the statistical properties of halos.Comment: 12 pages, 14 figures. Accepted by MNRAS. Adopted an improved algorithm for halo finding and added a comparison with NFW model

Techno-economic assessment of an industrial carbon capture hub sharing a cement rotary kiln as sorbent regenerator

The concept of CCS cluster brings together multiple CO2 industrial emitters using shared capture and/or transportation infrastructure and offers several advantages for network partners compared with point-to-point individual projects. It reduces costs for CCS, and enables CO2 capture from small volume industrial facilities. The proposed concept connects a cluster of industrial sites with significant heat demands with a cement plant through the implementation of a Ca-looping CCS system. This system treats the flue gas from all the industrial emitters in independent boiler/carbonators while uses the kiln furnace as calciner for the cement and the capture plant. The carbonator reactors located in each one of the industry sites are fed by CaO from the cement plant to capture the CO2 content of their own flue gas. After carbonation reaction, the exhaust sorbent is transported back to the cement plant for regeneration in the kiln furnace. The aim of this work is to analyse the techno-economic feasibility of the proposed Ca-looping CCS cluster. The economic assessment, assuming 20 euro/ton CaO and carbon market 30 euro/ton CO2 points out the feasibility of this kind of centralized carbon capture system to handle the carbon from small emitters. Results show that the operating costs of small companies that use coal or natural gas reduce from 21.3 Meuro to 18.8 Meuro or from 25.5 to 23.0 Meuro. For the cement industry this income lessens its operating costs 1.9 Meuro lower than a reference situation where CCS is only implemented in cement plant

Gingival hyperplasia around dental implants in jaws reconstructed with free vascularized flaps: a case report series

Free vascularized flaps are the gold standard for reconstruction of the facial skeleton after surgical ablation of pathologies or when important atrophy of the jaws exists. A frequent problem seen during prosthetic rehabilitation after reconstruction with free vascularized flaps is the onset of hyperplastic granulomatous reactive tissue around the prosthetic abutment of the implant. The features of this phenomenon seem to be directly related to the characteristics of the periimplant tissue and of the manufacturing materials of the prosthesis and abutments. This complication can be seen quite often; we found it in 7 of 40 patients (17.5%). It does not seem to significantly affect the survival rate of implants. The aim of the study was to analyze the behavior of such lesions and to suggest our clinical approach with the management of these kinds of patients and complications. To remove gingival hyperplasia, we used either a traditional cold scalpel or an electric cautery or laser. We had good results using these tools. The onset of this phenomenon was not influenced by either the kind of implant and free flaps used or by the local conditions of the patients (such as radiotherapy). The number of recurrences was highly influenced by the oral hygiene of the patients

Fem and Von Mises analysis of OSSTEM ® dental implant structural components: evaluation of different direction dynamic loads

Abstract PURPOSE: The objective of this investigation is to study prosthodontics and internal components resistance to the masticatory stress and considering different force directions by using Finite Element Method analysis (FEM). The structural materials of the components are usually Titanium alloy grade 4 or 5 and thus, guarantee the integration of the fixture in the bone due to the osteointegration phenomena. Even if the long-term dental implant survival rate is easy to be obtained and confirmed by numerous researches, the related clinical success, due to the alteration of the mechanical and prosthodontics components is still controversial. METHODS: By applying engineering systems of investigations like FEM and Von Mises analyses, it has been investigated how dental implant material was held against the masticatory strength during the dynamic masticatory cycles. A three-dimensional system involved fixture, abutment and the connection screws, which were created and analyzed. The elastic features of the materials used in the study were taken from recent literature data. RESULTS: Data revealed a different response for both types of devices, although implant neck and dental abutment showed better results for all conditions of loading while the abutment screw represented aweak point of the system. CONCLUSION: The data of this virtual model showed all the features of different prosthetic retention systems under the masticatory load. Clinicians should find better prosthetic balance in order to better distribute the stress over the component and to guarantee patients' clinical long-term results

Oral proliferative verrucous leukoplakia: Progression to malignancy and clinical implications. systematic review and meta‐analysis

Aim: The aim of the present systematic review was to investigate the risk of malignant transformation of proliferative verrucous leukoplakia (PVL). Materials and Methods: the search was carried out using a combination of terms (leukoplakia OR leucoplakia) AND (multifocal OR proliferative) on the following databases: PubMed, Scopus, Web of Science (WOS Core Collection), Cochrane Library, selecting only articles published since 1985 and in the English language. Demographic, disease‐related, and follow‐up data extracted from the studies included in the qualitative synthesis were combined. Weighted means ± standard deviations were calculated for continuous variables, while categorical variables were reported as frequencies and percentages. Dichotomous outcomes were expressed as odd ratios (ORs) with 95% confidence intervals (CIs). Odd ratios for individual studies were combined using a random‐effects meta‐analysis, conducted using Review Manager 5.4 Software (Cochrane Community, Oxford, England). Results: twenty‐two articles were included, with a total of 699 PVL patients, undergoing a mean follow‐up of 7.2 years. Sixty‐six percent of patients were females, with a mean age of 70.2 years, and 33.3% were males, with a mean age of 59.6 years. Most patients were non‐smokers and non‐alcohol users, and the gingiva/alveolar ridge mucosa was the most involved anatomical site by both PVL appearance and malignant transformation. A total of 320 PVL patients developed oral verrucous carcinoma (OVC) or conventional oral squamous cell carcinoma (OSCC) because of malignant transformation of PVL lesions (45.8%). A statistically significant 3.8‐fold higher risk of progression to conventional OSCC was found compared to OVC in PVL patients, with women being 1.7 times more likely to develop oral cancer than men, as a consequence of PVL progression. Moreover, a statistically significant higher likelihood of developing conventional OSCC in female PVL patients than in males was found. In 46.5% of patients with PVL malignant transformation, multiple carcinomas, in different oral sites, occurred during follow‐up. Conclusions: PVL is an aggressive lesion, which, in a high percentage of cases (almost 50%), undergoes malignant transformation, mainly toward OSCC. The female gender is most affected, especially in the elderly, with a negative history for alcohol and tobacco consumption

COMPORTAMENTO AD ALTA PRESSIONE DI TRASDUTTORI PIEZOELETTRICI PER APPLICAZIONI DI GEOFISICA SPERIMENTALE

L’investigazione del comportamento acustico di campioni di roccia implica l’uso di trasduttori piezoelettrici [Spinelli et al., 2009], sia in uso attivo (eccitazione e rilevazione) che passivo (rilevazione delle onde elastiche generate da fenomeni di fratturazione). In alcuni casi vengono imposte elevate pressioni per simulare le condizioni di sconfinamento del campione di roccia in profondità, utilizzando un liquido o un gas. La natura dei trasduttori piezoelettrici suggerisce che essi non debbano soffrire molto in ambienti in cui la variazioni di pressione o la pressione di esercizio sia un elemento non trascurabile e possono essere utilizzati in tali condizioni senza particolari precauzioni con evidenti vantaggi nella semplificazione del set-up sperimentale. Questa nota è la descrizione delle misure condotte per caratterizzare dei trasduttori piezoelettrici, nell’intervallo di pressione di interesse (0 - 1000 atm), da utilizzare per scopi sperimentali nell’ambito del progetto europeo ERC Starting Grant Project GLASS InteGrated Laboratories to investigate the mechanics of ASeismic vs. Seismic faulting. Per fare ciò due trasduttori sono stati incollati direttamente tra loro in modo da realizzare un quadripolo, con una porta d’ingresso e una di uscita, e ne è stata rilevata la caratteristica ingresso – uscita al variare della frequenza. Per il rilevamento delle caratteristiche elettriche sono stati usati differenti strumenti di misura: un generatore di segnali, un oscilloscopio e un analizzatore di reti vettoriale. Per imporre sui campioni una pressione controllata è stato allestito un apparato meccanico dedicato, formato da un insieme pistone-cilindro all’interno del quale viene alloggiata la coppia di trasduttori incollati. Nel cilindro viene inserito olio (adeguatamente incomprimibile ed elettricamente isolante) come vettore di pressione; la spinta sul pistone viene esercitata attraverso una pressa idraulica. Una particolare cura è stata posta nella costruzione del passacavo a tenuta per alte pressioni. Nei paragrafi che seguono verranno dapprima descritti i trasduttori usati per gli esperimenti e l’apparato meccanico, quindi si passerà alla presentazione delle misure effettuate in varie condizioni e con i vari strumenti