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

Arf6 regulates the cycling and the readily releasable pool of synaptic vesicles at hippocampal synapse.

Recycling of synaptic vesicles (SVs) is a fundamental step in the process of neurotransmission. Endocytosed SV can travel directly into the recycling pool or recycle through endosomes but little is known about the molecular actors regulating the switch between these SV recycling routes. ADP ribosylation factor 6 (Arf6) is a small GTPase known to participate in constitutive trafficking between plasma membrane and early endosomes. Here, we have morphologically and functionally investigated Arf6-silenced hippocampal synapses and found an activity dependent accumulation of synaptic endosome-like organelles and increased releasecompetent docked SVs. These features were phenocopied by pharmacological blockage of Arf6 activation. The data reveal an unexpected role for this small GTPase in reducing the size of the readily releasable pool of SVs and in channeling retrieved SVs toward direct recycling rather than endosomal sorting. We propose that Arf6 acts at the presynapse to define the fate of an endocytosed SV

Organisation of diagnosis and treatment of idiopathic pulmonary fibrosis and other interstitial lung diseases in the Nordic countries

To access publisher's full text version of this article click on the hyperlink at the bottom of the pageDifferences in the organisation of idiopathic pulmonary fibrosis (IPF) and interstitial lung diseases (ILDs) in the Nordic countries are not well described. Diagnostic setups, treatment modalities and follow-up plans may vary due to national, cultural and epidemiological features. The aim of the present study was to describe the different organisation of diagnostics and treatment of IPF and ILD in the Nordic countries. Methods All university and regional hospitals with respiratory physicians were invited to respond to a questionnaire collecting data on the number of physicians, nurses, patients with ILD/IPF, the presence of and adherence to disease-specific national and international guidelines, diagnosis and treatment including ILD-specific palliation and rehabilitation programmes. Results Twenty-four university and 22 regional hospitals returned the questionnaire. ILD and IPF incidence varied between 1.4 and 20/100,000 and 0.4 and 10/100,000, respectively. Denmark and Estonia have official national plans for the organisation of ILD. The majority of patients are managed at the university hospitals. The regional hospitals each manage 46 (5–200) patients with ILD and 10 (0–20) patients with IPF. There are from one to four ILD centres in each country with a median of two ILD specialists employed. Specialised ILD nurses are present in nine hospitals. None of the Nordic countries have national guidelines made by health authorities. The respiratory societies in Sweden, Norway and Denmark have developed national guidelines. All hospitals except two use the ATS/ERS/JRS/ALAT IPF guidelines from 2011. The limited number of ILD specialists, ILD-specialised radiologists and pathologists and the low volume of ILD centres were perceived as bottlenecks for implementation of guidelines. Twenty of the 24 university hospitals have multidisciplinary conferences (MDCs). Pulmonologists and radiologists take part in all MDCs while pathologists only participate at 17 hospitals. Prescription of pirfenidone is performed by all university hospitals except in Estonia. Triple therapy with steroid, azathioprine and N-acetylcysteine is not used. No hospitals have specific palliation programmes for patients with ILD/IPF, but 36 hospitals have the possibility of referring patients for palliative care, mostly based on existing oncology palliative care teams; seven hospitals have rehabilitation programmes for ILD. Conclusion There are obvious differences between the organisations of ILD patients in the Nordic countries. We call for national plans that consider the challenge of cultural and geographical differences and suggest the establishment of national reference centres and satellite collaborative hospitals to enable development of common guidelines for diagnostics, therapy and palliation in this patient group

Jol-m M . VeiJ..l.cu A

I-OSAlamos Abstract RF plasma glow discharges are being investigated for removing and recovering radioactive elements from contaminated objects, especially those contaminated with transuranic (TRU) materials. These plasmas, using nitrogen trifluoride as the working gas, have been successful at removing uranium and plutonium contaminants from test coupons of stainless steel and aluminum surfaces, including small cracks and crevices, and the interior surfaces of relatively hard to reach aluminum pipes. Contaminant removal exceeded 99.9% from simple surfaces and contaminant recovery using cryogenic traps has exceeded 50$Z0. Work continues with the objective of demonstrating that transuranic contaminated waste can be transformed to low level waste (LLW) and to better understand the physics of the interactions between plasma and surface contaminants. This work summarizes the preliminary results from plasma decontamination from the interior of aluminum objects-the nooks and crannies experiments

Optimization of Enzymatic Production of Oligopeptides from Apricot Almonds Meal with Neutrase and N120P

Neutrase 0.8L and N120P proteases were used for oligopeptide production from apricot almonds meal, and response surface design was carried out to optimize the effect of hydrolysis conditions on hydrolysis degree (DH) and oligopeptide yield rate. Four independent variables were used to optimize the hydrolysis process: hydrolysis temperature (X1), enzyme-to substrate ratio (E/S) (X2), substrate concentration (X3) and reaction time (X4). Statistical analysis indicated that the four variables, quadratic terms of X1, X3, and X4, and the interaction terms with X1 had a significant (p < 0.05) effect on DH. The yield rate was also significantly affected by the four variables and quadratic terms of X1, X2 and X4. Two mathematical models with high determination coefficient were obtained and could be employed to optimize protein hydrolysis. The optimal hydrolysis conditions were determined as follows: hydrolysis temperature 52.5 °C; enzyme-to-substrate ratio (E/S) 7200 U/g; substrate concentration 2%; reaction time 173 min. The initial pH 6.5 and Neutrase-to-N120P dosage ratio 2:1 were fixed in this study according to the preliminary research. Under these conditions, the experimental DH and yield rate were 34.10 ± 5.25% and 72.42 ± 2.27%, respectively