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Effect of Acetone Vapor Smoothing Process on Surface Finish and Geometric Accuracy of Fused Deposition Modeling ABS Parts

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Journal of Materials Science and Chemical Engineering 2022年第10期10卷 1-9页

作者： Viviane Pestano Mariana Pohlmann fabio pinto da Silva Design and Materials Selection Lab Postgraduate Program in Design Federal University of Rio Grande do Sul Porto Alegre Brazil

FDM is a widely used additive manufacturing process, however, it has some limitations, such as surface finish, due to the staircase effect caused by the layer-by-layer deposition. Studies have been conducted on surface finish of ABS parts with the use of acetone, but the process parameters and the resulting effects have not been fully investigated in the literature. Therefore, the aim of this study was to investigate the effects of acetone vapor smoothing process on surface finish and geometric accuracy of fused deposition modeling ABS parts. Specimens with different geometries were created and printed using two directions in different scales. The parts were exposed to acetone vapor for 20, 30 and 40 minutes. 3D deviation maps, roughness and microscopic analyses were conducted. The staircase effect was reduced at the expense of some geometric deviations, which varied according to the exposure time and part orientation. The smoothing process applied to the flat surfaces proved to be quite effective in reducing roughness by 90%, however, this reduction led to an undesirable rounding of the sharp edges. The results obtained in this study are consistent with those found in the literature and may help improve the quality of the ABS printed parts.

关键词： Additive Manufacturing 3D Printing FDM Staircase Effect Acetone Vapor Polishing

Production of Aflatoxins from Aspergillus flavus in Liquid Medium

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Journal of Life Sciences 2013年第4期7卷 377-381页

作者： Maria Edite Bezerra da Rocha Francisco das Chagas Oliveira Freire Icaro Gusmao pinto vieira Jose Mariados Santos Filho fabio Erlan Feitosa Maia Maria Izabel Florindo Guedes Davide Rondina Universidade Estadual do Ceara Avenida Paranjana 1700 CEP: 60740-000 Fortaleza Ceara Brasil Embrapa Agroindustria Tropical Rua Dra. Sara Mesquita 2270 CEP: 60.511-110 Fortaleza-CE Brasil

Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus, and can be found in many grains such as peanuts, soybeans and com. This study aimed to qualitatively and quantitatively evaluate the production of aflatoxin in liquid media using strains of Aspergillus flavus obtained from peanuts marketed in the city of Fortaleza, CEo Strains of Aspergillus flavus were inoculated into a liquid medium malt extract and after 2 days inoculated into a second medium containing sucrose 5%, MgSO4·7H20 0.1%, KH2PO4 1%, ZnSO4·7H2O 0.0176 g, and cultured for 3 more days. The media were kept at room temperature ranging from 24°C to 32 °C with agitation of 130 rpm and aeration of 4.17 Llmin. Qualitative analysis was performed by thin layer chromatography and quantitatively by high performance liquid chromatography with fluorescence detection, demonstrating the production of aflatoxin B I （588 mg/L） and B2 （929 mg/L）.

关键词： Peanut fungi micotoxins chromatography.

An Over-Moded TEM Cell System for <i>in vivo</i>Exposure at 2.45 GHz

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Journal of Electromagnetic Analysis and Applications 2012年第9期4卷 345-352页

作者： Alessandra Paffi Caterina Merla Micaela Liberti fabio Fratta Rosanna pinto Giorgio A. Lovisolo Francesca Apollonio Italian Inter-University Centre of Electromagnetic Fields and Bio-Systems Department of Information Engineering Electronic and Telecommunication University of Rome “La Sapienza” Rome 00184 Italy Italian Inter-University Centre of Electromagnetic Fields and Bio-Systems Department of Information Engineering Electronic and Telecommunication University of Rome “La Sapienza” Rome 00184 Italy Italian Inter-University Centre of Electromagnetic Fields and Bio-Systems Italian National Agency for New Technologies Energy and Sustainable Economic Development Rome 00123 Italy.

A TEM cell designed to operate at 900 MHz for exposing small-restrained animals (e.g. mice) has been theoretically, numerically and experimentally characterized at 2.45 GHz, which is the central frequency of the WiFi protocol. This study aims at evaluating the influence of higher order modes on the field homogeneity. The results demonstrate the superimposition of a tolerable standing wave, due to reflections at the cell terminations, and a slight beat wave due to the interference between different modes. Nevertheless, the final outcome is that the system can still be efficiently used to expose small animals in specific WiFi channels, provided they are properly placed in correspondence to the maxima of the electric field along the guide length.

关键词： in vivo Experiments Exposure System TEM Cell WiFi Signal

Relationship between Physical Activity Level, Hepatic Steatosis Presence, Metabolic Syndrome and the Risk of Developing Type 2 Diabetes in Men

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Health 2016年第15期8卷 1778-1787页

作者： Carla Giuliano de Sá pinto Montenegro Marcio Marega José Antonio Maluf de Carvalho Luis Felipe Tubagi Polito Rafael Mathias Pitta fabio Luis Ceschini Danilo Sales Bocalini Aylton José Figueira Albert Einstein Israelita Hospital S&atilde o Paulo Brazil Sã o Judas Tadeu University S&atilde o Paulo Brazil

Cardiovascular disease, cancer, respiratory and metabolic disease represent 63% of all deaths worldwide and are considered the major causes of morbidity and mortality. Physical inactivity is considered a case of public health, and other behavioral and metabolic risk factors, according to WHO (2011), such as smoking, increased blood pressure, increased blood glucose, hypercholesterolemia, overweight and obesity. The Nonalcoholic Fatty Liver Disease (NAFLD) is the most prevalent liver disease in adults, and can progress and be characterized as hepatic steatosis (HS) which is derived from the accumulation of lipids in hepatocytes, and histopathologic condition is more than 5% of the weight of liver. So, the purpose of this study is to identify the relationship between the physical activity level and the hepatic steatosis presence, metabolic syndrome and the risk of developing type 2 diabetes mellitus in men. We evaluated retrospectively medical records of 1399 men (40.7 ± 8.18 years old) who participated in the protocol of Preventive Health Check-up at Hospital Israelita Albert Einstein from January to October 2011. According to the results, it is concluded that there is a positive association between low physical activity level and the presence of Hepatic steatosis. The results further demonstrate that, despite the high BMI, blood levels of the subjects remained unchanged. Even without a positive association between these variables, the results showed a high risk behavior for the development of diabetes mellitus type 2.

关键词： Physical Activity Hepatic Steatosis Metabolic Syndrome Type 2 Diabetes

Analysis of Cocaine and Crack Cocaine via Thin Layer Chromatography Coupled to Easy Ambient Sonic-Spray Ionization Mass Spectrometry

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American Journal of Analytical Chemistry 2011年第6期2卷 658-664页

作者： Bruno D.Sabino Wanderson Romao Morena L.Sodre Deleon N.Correa Denise B.Rocha pinto fabio O.M.Alonso Marcos N.Eberlin Institute of Criminalistic Carlos Eboli Rio de JaneiroBrazil National Institute of Metrology Standardization and Industrial QualityAv.N.Sra.das GracasDuque de CaxiasBrasil ThoMSon Mass Spectrometry Laboratory Institute of ChemistryUniversity of CampinasCampinasBrazil

Cocaine and crack cocaine are usually seized with a great diversity of adulterants, such as benzocaine, lidocaine, caffeine, and procaine. The forensic identification of cocaine in these drug mixtures is normally performed using colorimetric testing kits, but these tests may suffer from interferences providing false-positive or false-negatives. In this work, we describe the use of thin layer chromatography coupled to easy sonic-spray ambient ionization mass spectrometry (TLC/EASI-MS) for rapid and secure analysis of cocaine and crack cocaine. Fifteen cocaine samples were analyzed, and all of them revealed positive TLC/EASI-MS results for cocaine, but other drugs and adulterants were also detected such as lidocaine, caffeine, benzocaine, lactose, benzoylecgonine, and ecgonidine. False positives and false negatives, as judged by the TLC Rf values, were identified via on-spot characterization by EASI-MS. The TLC/EASI-MS combination seems therefore to provide an appropriate technique for secure forensic investigations of illicit drugs.

关键词： Cocaine Crack TLC Illicit Drug EASI-MS

The Aging Bladder in Females Evaluated by Urodynamics

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Open Journal of Urology 2017年第3期7卷 54-64页

作者： M. C. de Albuquerque Neto Leslie Clifford Noronha Araujo Thome Decio Pinheiro Barros Junior Joao Luiz Amaro Flavia Cristina Morone pinto fabio de Oliveira Vilar Salvador Vilar Correia Lima Urologic Department Clinical Hospital Federal University of Pernambuco UFPE Recife Brazil Urologic Service Botucatu Medical School Paulista State University UNESP Botucatu Brazil Postgraduate Program in Surgery Department of Surgery Center for Health Sciences Federal University of Pernambuco UFPE Recife Brazil

Aim: To determine whether bladder functions deteriorate with age. Methods: Data contained in electronic medical record (INFOMED?) were used in this institutional retrospective review. Analysis was done on the urodynamic studies in women over 18 years old conducted between May 2011 and November 2015. Patients with previous history of pelvic surgery or radiotherapy, neurological disease, vaginal prolapse greater than grade I, congenital urogenital malformations, urinary obstructive disease, diabetes, or the use of any medication that could interfere with bladder function were excluded from the analysis. The urodynamic parameters analyzed were the Maximum Cystometric Capacity (MCC), Voiding Volume (VV), Maximum Flow (Qmax), Bladder Compliance (BC), Detrusor Pressure at Maximum Flow (PdetQmax), Bladder Contractility Index (BCI), Bladder Voiding Efficiency (BVE) and Post-Void Residual Urine Volume (PVR). Patients were further stratified in five groups according to age (A—18 to 40;B—41 to 50;C—51 to 60;D—61 to 70;E—over 70 years old). Results: Out of 3103 urodynamic studies analyzed, 719 were eligible for the study. The average age of patients was 49.3 (+13.2) years old and in all evaluated parameters, statistically significant correlation between age and decline of bladder function was obtained (p Conclusions: This study showed a decline in bladder storage function (reduction in MCC and BC) and in bladder emptying function (reduction in Qmax, PdetQmax, VV, BCI and BVE with an increase in PVR) with age.

关键词： Aging Urinary Bladder Diseases Urinary Bladder Neurogenic Overactive Urodynamics