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1.
Heliyon ; 9(4): e15060, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37089321

RESUMO

Delamination is a major failure mode affecting laminated composite structures. This failure mechanism, if not properly monitored, can lead to uncontrolled cracks growth and premature structural collapse. Thus, predicting delamination propagation is mandatory to determine the structural integrity. At present, delamination has been extensively investigated in laminated composite structures but only a few studies have been performed on how the intralaminar damages influence the interfacial release energy and, consequently, the delamination evolution. In this paper, the well-established SMart-Time XB delamination simulation tool, has been coupled with a Hashin Criteria based User-Material Subroutine (UserMat) to study the role of the intralaminar damages in delamination propagation. A benchmark case based on the mixed-mode I/II Single Leg Bending (SLB) specimen for delamination evolution assessment under quasi-static loading has been investigated. Subsequently, a composite material plate, characterized by an artificial circular delamination, under compression has been considered. This study proved to be valuable by underlining the influence of fibre and matrix breakage on the interlaminar damages evolution. Interestingly, taking into account the effect of intralaminar flaws changes the local energy release rates values on the delamination front and, consequently, the crack shape and evolution.

2.
Heliyon ; 8(11): e11695, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36468130

RESUMO

This paper deals with the use of shock absorbers, placed in the upper roof of vehicles, able to increase the safety of passengers during an impact event. Numerical impact analyses have been introduced to demonstrate the effectiveness of these shock absorbers by assessing the deformations, stress and energy dissipation capabilities in the different structural components of a vehicle, somehow related to the safety of passengers. Indeed, shock absorbers have been found to play an important role in relation to passengers' safety. The homologation limitations of the reference regulation have been taken into account: FMVSS No. 201U "internal head impact - passenger compartment". This regulation, actually, provides a fundamental parameter, known as HIC(d) - "Head Injury Criteria", which is strictly related to the injuries of the passenger head under impact conditions alongside the rigid components inside the vehicle. The HIC(d) threshold value, if exceeded, affects the final conformity test of a vehicle. Hence, to fall within the range of reliable values of the HIC(d), shock absorbers need to be adopted. In order to increase these shock absorbers efficiency, in terms of passenger safety, in compliance with the regulations, the possibility of production of such devices by additive manufacturing techniques has been assessed.

3.
Med Oral Patol Oral Cir Bucal ; 26(1): e71-e77, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247578

RESUMO

BACKGROUND: It is a common opinion that Primary Sjögren Syndrome (pSS) damages the exocrine glands and determines the reduction of secreted saliva, some studies show that there are qualitative anomalies of the mucins produced in saliva, including MUC7, MUC5B, MUC1. The purpose of this study is to trace all the information useful to establish whether there is a qualitative or quantitative defect of the mucins in the pSS. MATERIAL AND METHODS: We reviewed the literature by looking for publications relevant to the topic in electronic databases. Sixteen articles met the search criteria. The studies were divided into two categories, those that studied the rheological characteristics of the saliva and those that studied the structural and / or metabolism modifications of the muciparous cells in the salivary glands. RESULTS: in Patients with pSS, xerostomia and the reduction of salivary spinnbarkeit are only partially related to the reduction of the unstimulated salivary flow. In pSS, pathological alterations of mucins' chemical-physical properties prevail as a cause of the clinical characteristics. Moreover, in pSS there are structural and metabolism changes in salivary glands' muciparous cells. CONCLUSIONS: There is much evidence that supports the presence of qualitative alterations in the saliva's rheological properties in Patients with pSS, and these are the main cause, more than the reduction of the unstimulated salivary flow, of the disease clinical characteristics - dry mouth and complications in the oral cavity. Therefore we propose to add to the classification criteria of pSS also a qualitative test of salivary glycoproteins.


Assuntos
Síndrome de Sjogren , Xerostomia , Humanos , Mucinas , Saliva , Glândulas Salivares , Síndrome de Sjogren/complicações
4.
J Prev Med Hyg ; 61(1): E31-E38, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32490267

RESUMO

INTRODUCTION: Radon and its decay products may cause substantial health damage after long-term exposure. The aim of the study was to perform a spatial analysis of radon concentration in the Salento peninsula, province of Lecce (South-eastern Italy) in order to better characterize possible risk for human health, with specific focus on lung cancer. METHODS: Based on previous radon monitoring campaigns carried out in 2006 on behalf of the Local Health Authority (ASL Lecce) involving 419 schools and through the application of kriging estimation method, a radon risk map was obtained for the province of Lecce, in order to determine if areas with higher radon concentrations were overlapping with those characterized by the highest pulmonary cancer incidence and mortality rates. RESULTS: According to our data, areas at higher radon concentrations seem to overlap with those characterized by the highest pulmonary cancer mortality and incidence rates, thus indicating that human exposure to radon could possibly enhance other individual or environmental pro-carcinogenic risk factors (i.e. cigarette smoking, air pollution and other exposures). CONCLUSIONS: The radon risk should be further assessed in the evaluation of the causes resulting in higher mortality and incidence rates for pulmonary cancer in Salento area vs Italian average national data. For these reasons, ASL Lecce in cooperation with ARPA Puglia and CNR-IFC has included the monitoring of individual indoor radon concentrations in the protocol of PROTOS case-control Study, aimed at investigating the role of different personal and environmental risk factors for lung cancer in Salento.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Neoplasias Pulmonares/epidemiologia , Radônio , Instituições Acadêmicas , Monitoramento Ambiental , Humanos , Incidência , Itália/epidemiologia , Neoplasias Pulmonares/mortalidade , Análise Espacial
6.
J Child Orthop ; 12(5): 502-508, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30294376

RESUMO

PURPOSE: Postoperative protocols following surgical management of supracondylar humerus fractures (SCFs) are often based upon surgeon preference rather than clinical merit. The purpose of this study is to determine the utility of early clinical and radiographic follow-up. METHODS: A retrospective review of patients who underwent closed reduction and percutaneous pinning (CRPP) for SCF between 2009 and 2015 was performed using a database of prospectively-collected consecutive patient data. Previously undiagnosed neuropathies documented at the first postoperative visit were identified. Unscheduled visits and postoperative complications were compared between patients who were seen at one week and those with delayed first clinic visits. RESULTS: Of 873 patients, 823 (94.3%) were seen within ten days of surgery (early follow-up) and 50 (5.7%) had a delayed first clinic appointment. Among patients seen for early follow-up, 12 (1.5%) had a previously undocumented neuropathy diagnosed but only eight (1%) had an alteration of management secondary to clinical findings. Greater than 90% of patients seen for early follow-up had radiographs performed, but only one had an alteration in management due to radiographic findings. Patients seen for early follow-up had the same rate of unscheduled visits (2.9% versus 4%, p = 0.66) and postoperative complications (1.6% versus 0%, p > 0.99) as those with delayed first appointments. Radiographic parameters were comparable at final follow-up (Baumann's angle 74.5° versus 73.7°, p = 0.40; lateral humeral condylar angle 40.2° versus 41.2°, p = 0.53). CONCLUSION: The early follow-up visit after CRPP of SCF rarely leads to alterations in care and does not reduce unscheduled visits or late complications. LEVEL OF EVIDENCE: Level IV.

7.
Clin Exp Allergy ; 48(9): 1092-1106, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29904978

RESUMO

Nasal cytology is an easy, cheap, non-invasive and point-of-care method to assess nasal inflammation and disease-specific cellular features. By means of nasal cytology, it is possible to distinguish between different inflammatory patterns that are typically associated with specific diseases (ie, allergic and non-allergic rhinitis). Its use is particularly relevant when other clinical information, such as signs, symptoms, time-course and allergic sensitizations, is not enough to recognize which of the different rhinitis phenotypes is involved; for example, it is only by means of nasal cytology that it is possible to distinguish, among the non-allergic rhinitis, those characterized by eosinophilic (NARES), mast cellular (NARMA), mixed eosinophilic-mast cellular (NARESMA) or neutrophilic (NARNE) inflammation. Despite its clinical usefulness, cheapness, non-invasiveness and easiness, nasal cytology is still underused and this is at least partially due to the fact that, as far as now, there is not a consensus or an official recommendation on its methodological issues. We here review the scientific literature about nasal cytology, giving recommendations on how to perform and interpret nasal cytology.


Assuntos
Citodiagnóstico , Mucosa Nasal/patologia , Rinite/diagnóstico , Animais , Biofilmes , Biópsia , Citodiagnóstico/métodos , Humanos , Mucosa Nasal/imunologia , Mucosa Nasal/microbiologia , Padrões de Prática Médica , Pesquisa , Rinite/etiologia , Irrigação Terapêutica
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3953-3956, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060762

RESUMO

The Attention Network Task (ANT) was developed to disentangle the three components of attention identified in the Posner's theoretical model (alerting, orienting and executive control) and to measure the corresponding behavioral efficiency. Several fMRI studies have already provided evidences on the anatomical separability and interdependency of these three networks, and EEG studies have also unveiled the associated brain rhythms. What is still missing is a characterization of the brain circuits subtending the attentional components in terms of directed relationships between the brain areas and their frequency content. Here, we want to exploit the high temporal resolution of the EEG, improving its spatial resolution by means of advanced source localization methods, and to integrate the resulting information by a directed connectivity analysis. The results showed in the present study demonstrate the possibility to associate a specific directed brain circuit to each attention component and to identify synthetic indices able to selectively describe their neurophysiological, spatial and spectral properties.


Assuntos
Encéfalo , Atenção , Eletroencefalografia , Função Executiva , Humanos , Orientação
9.
Mar Pollut Bull ; 121(1-2): 230-237, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28602310

RESUMO

The aim of this work is to verify the impact of anthropogenic activities and the effects of accidental events, e.g. oil spills, on the marine environment. For this reason, marine sediments and soil samples were collected in the inner part of Vigo and Pontevedra bays, in the Galicia region, northwest Spain, an area interested by many events of oil spills and also characterized by coastal areas with intense anthropic activities; also Cíes Islands, a natural protected area facing the Vigo bay, was investigated, as background site. PAHs, heavy hydrocarbons and metals were analyzed according to standard methods, in order to satisfy quality assurance and quality check constraints. Total PAHs concentration (Σ16 compounds) were in the range of 25-4000ng/g, and 30-800ng/g for marine sediments and soil samples, respectively. Even some samples from the Cíes Islands, show a contamination with values achieving >200ng/g of PAHs. Although contamination levels have been shown to be strong at several locations in the study area, their ranges are those typical of other estuarine sites, with PAHs and hydrocarbons primarily of pyrolytic origin. This observation was further confirmed by enrichment factors of some metals (Cd, Cu, Pb and Zn) that match to those of harbor and shipyard zones of the main industrial and commercial maritime areas.


Assuntos
Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos , Espanha
10.
Clin Genet ; 91(1): 3-13, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27363536

RESUMO

Imprinting disorders (ImpDis) are a group of currently 12 congenital diseases with common underlying (epi)genetic etiologies and overlapping clinical features affecting growth, development and metabolism. In the last years it has emerged that ImpDis are characterized by the same types of mutations and epimutations, i.e. uniparental disomies, copy number variations, epimutations, and point mutations. Each ImpDis is associated with a specific imprinted locus, but the same imprinted region can be involved in different ImpDis. Additionally, even the same aberrant methylation patterns are observed in different phenotypes. As some ImpDis share clinical features, clinical diagnosis is difficult in some cases. The advances in molecular and clinical diagnosis of ImpDis help to circumvent these issues, and they are accompanied by an increasing understanding of the pathomechanism behind them. As these mechanisms have important roles for the etiology of other common conditions, the results in ImpDis research have a wider effect beyond the borders of ImpDis. For patients and their families, the growing knowledge contributes to a more directed genetic counseling of the families and personalized therapeutic approaches.


Assuntos
Epigênese Genética , Doenças Genéticas Inatas/genética , Loci Gênicos/genética , Impressão Genômica , Mutação , Variações do Número de Cópias de DNA/genética , Aconselhamento Genético , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/terapia , Testes Genéticos/métodos , Humanos , Dissomia Uniparental/genética
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