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1.
Arch Oral Biol ; 122: 105032, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33418435

RESUMO

OBJECTIVES: This study aims to investigate the effects of tea extracts on biofilm formation by oral streptococci and the potential mechanisms behind the effects. DESIGN: We examined the effects of five types of tea extracts (green, oolong, black, pu-erh and chrysanthemum tea) on cell surface hydrophobicity and auto-aggregation of three different streptococcal species (Streptococcus mutans, Streptococcus salivarius and Streptococcus mitis) and evaluated their biofilm formation on four disparate hard surfaces (glass, stainless steel, hydroxyapatite and titanium). The correlation between biofilm formation and the cellular properties were investigated in order to study the mechanisms by which the tea extracts affect biofilm formation. RESULTS: Results show that the tea extracts reduced cell surface hydrophobicity (by up to 57.9 %) and, in some cases, altered cellular auto-aggregation (by up to 12 %) and biofilm formation (by up to 2.61 log CFU cm-2). Specifically, oolong tea extract was found to enhance biofilm formation by increasing cellular auto-aggregation and pu-erh tea extract retarded biofilm formation by increasing auto-aggregation. Biofilm formation correlated well to cell surface hydrophobicity and auto-aggregation in combination, but not to either one alone as determined by multiple linear regression analysis. CONCLUSIONS: Tea extracts have the ability to modulate streptococcal biofilm formation by altering cell surface hydrophobicity and cellular aggregation.


Assuntos
Biofilmes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Chá/química , Durapatita , Vidro , Interações Hidrofóbicas e Hidrofílicas , Aço Inoxidável , Titânio
2.
J Environ Manage ; 277: 111460, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254842

RESUMO

This paper addresses the lifecycle cost assessment of a steel girder bridge considering the material costs and maintenance activities along the bridge's lifecycle. A reference highway bridge case study is chosen. It was initially designed using carbon steel S355. Two more steel grades are included in the comparison: high strength carbon steel S460 and duplex stainless steel EN 1.4162. For each design option, fatigue appears to be the driving design criterion for the following critical welded details: transversal stiffeners, cope holes and full penetration butt welds in the flanges. In addition to ultimate limit state verifications, specific attention is therefore given to fatigue through the use of different verification methods: the well-known nominal stress method and the hot spot stress method. It is concluded that the net present value of the lifecycle cost of the stainless steel option is attractive compared to painted the carbon steel options.


Assuntos
Carbono , Aço Inoxidável , Adaptação Psicológica , Pintura , Aço
3.
Bioresour Technol ; 319: 124143, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33039846

RESUMO

Stainless steel membranes with 0.45, 1 and 2 µm pore sizes were applied to harvest cyanobacteria. Their critical fluxes were determined and continuous filtration tests were conducted. Two novel transition-combined models for constant flux filtration were developed and applied to describe observed variations in fouling. A pyrolysis cleaning method was proposed and tested. The results showed that the 2 µm membrane was preferable for practical applications as it could process more than twice the filtrate volume before clogging than the other two membranes, with an 8% reduction in rejection rate. The transition-cake-intermediate model predicted fouling better than the combined models, and the fouling mainly resulted from cake formation. Pyrolysis cleaning removed the foulants more effectively and quicker while converting the foulants into desirable products, making it a promising cleaning method for heat-resisting membranes fouled by algae. But both cleaning methods could lead to the enlargement of pore sizes and porosity.


Assuntos
Cianobactérias , Aço Inoxidável , Filtração , Membranas Artificiais
4.
Angle Orthod ; 90(4): 587-597, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378494

RESUMO

OBJECTIVES: To investigate whether there was a difference in success rates when stainless steel (SS) was compared to titanium mini-implants (MIs) in orthodontic patients. MATERIALS AND METHODS: PubMed, Cochrane, Scopus, Web of Science, Lilacs, Google Scholar, Clinical Trials, and OpenGray were searched without restrictions. A manual search was also performed in the references of the included articles. Studies comparing the success rate between SS and titanium MIs were included. Risk of bias (RoB) was assessed using the ROBINS-I (Risk of Bias in Non-randomized Studies-of Interventions) Tool or RoB 2.0 according to the study design. The level of evidence was assessed through GRADE (Grading of Recommendation, Assessment, Development, and Evaluation). RESULTS: Six studies met the eligibility criteria. One study was a randomized clinical trial that evaluated extraalveolar MIs, and nonrandomized trials examined interradicular MIs. The RCT presented a low RoB, two nonrandomized trials presented a moderate risk, and three presented a high risk. The quality of the evidence was high for the randomized clinical trial and moderate for the nonrandomized trials. Most studies found no difference between materials, with good success rates for both (SS, 74.6%-100%; titanium: 80.9%-100%) and only one study, with a high RoB, showed a higher success rate with titanium MIs (90%) when compared with SS (50%). A quantitative analysis was not because of the great heterogeneity among the studies. CONCLUSIONS: Although limited, the current evidence seems to show that the material used is not a major factor in the success rate of MIs. Because it has a lower cost than titanium and presents similar clinical efficiency, SS is a great material for orthodontic MIs.


Assuntos
Aço Inoxidável , Titânio , Humanos
5.
ACS Appl Mater Interfaces ; 12(52): 58360-58368, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33337873

RESUMO

The SARS-CoV-2 virus that causes the COVID-19 epidemic can be transmitted via respiratory droplet-contaminated surfaces or fomites, which urgently requires a fundamental understanding of intermolecular interactions of the coronavirus with various surfaces. The corona-like component of the outer surface of the SARS-CoV-2 virion, named spike protein, is a key target for the adsorption and persistence of SARS-CoV-2 on various surfaces. However, a lack of knowledge in intermolecular interactions between spike protein and different substrate surfaces has resulted in ineffective preventive measures and inaccurate information. Herein, we quantified the surface interaction and adhesion energy of SARS-CoV-2 spike protein with a series of inanimate surfaces via atomic force microscopy under a simulated respiratory droplet environment. Among four target surfaces, polystyrene was found to exhibit the strongest adhesion, followed by stainless steel (SS), gold, and glass. The environmental factors (e.g., pH and temperature) played a role in mediating the spike protein binding. According to systematic quantification on a series of inanimate surfaces, the adhesion energy of spike protein was found to be (i) 0-1 mJ/m2 for hydrophilic inorganics (e.g., silica and glass) due to the lack of hydrogen bonding, (ii) 2-9 mJ/m2 for metals (e.g., alumina, SS, and copper) due to the variation of their binding capacity, and (iii) 6-11 mJ/m2 for hydrophobic polymers (e.g., medical masks, safety glass, and nitrile gloves) due to stronger hydrophobic interactions. The quantitative analysis of the nanomechanics of spike proteins will enable a protein-surface model database for SARS-CoV-2 to help generate effective preventive strategies to tackle the epidemic.


Assuntos
Vidro/química , Ouro/química , Poliestirenos/química , Glicoproteína da Espícula de Coronavírus/química , Aço Inoxidável/química , Adsorção , Fômites/virologia , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Propriedades de Superfície , Temperatura
6.
J Dent Child (Chic) ; 87(3): 147-152, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33349298

RESUMO

Purpose: The purposes of this study were to: (1) examine the longevity of resin crowns (RCs), pre-veneered stainless steel crowns (PVSSCs), and stainless steel crowns (SSCs) in primary maxillary incisors in a nationwide sample of private insurance claims; and (2) explore whether longer survival rates are related to the type of treating practitioner.
Methods: Private dental insurance claims were obtained from a national data warehouse. The paid insurance claims (2005 to 2016) included the treatment provided, number of teeth treated at an appointment, patient's age, and type of dentist.
Results: All three restoration types had acceptable longevity; however, SSCs and PVSSCs had significantly better longevity than RCs, with no significant difference in longevity between SSCs and PVSSC. The most common restoration of choice was SSCs (48 percent), followed by RCs (29.8 percent) and PVSSCs (22.2 percent).
Conclusion: SSCs and PVSSCs had greater longevity than resin crowns. The survival rate after six years was higher than 90 percent for all types of restorations. Teeth restored with SSCs lasted longer when placed by pediatric dentists than those placed by general dentists.


Assuntos
Coroas , Aço Inoxidável , Criança , Falha de Restauração Dentária , Restauração Dentária Permanente , Humanos , Incisivo , Estudos Retrospectivos , Dente Decíduo
7.
J Clin Pediatr Dent ; 44(6): 451-458, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378466

RESUMO

OBJECTIVE: The surface roughness of various orthodontic materials could affect biofilm formation and friction. The purpose of this study was to examine the surface roughness and chemical composition of the slots and wings of several ceramic self-ligating brackets. STUDY DESIGN: Four types of ceramic self-ligating brackets were separated into experimental groups (DC, EC, IC, and QK) while a metal self-ligating bracket (EM) was used as the control group. Atomic force microscopy and energy-dispersive x-ray spectroscope were used to examine the surface roughness and chemical composition of each bracket slot and wing. RESULTS: The control group was made of ferrum and chrome while all the experimental groups were comprised of aluminum and oxide. There was a statistically significant difference in the roughness average (Sa) among the various self-ligating brackets (p< 0.001 in slots and p<0.01 in the wing). The slots in the EC group had the lowest Sa, followed by the DC, IC, control, and QK groups. The wings in the IC group had the lowest Sa, followed by the EC, DC, control, and QK groups. CONCLUSIONS: There is a significant difference in the surface roughness of the slots and wings among several types of ceramic self-ligating brackets.


Assuntos
Braquetes Ortodônticos , Biofilmes , Cerâmica , Ligas Dentárias , Fricção , Humanos , Teste de Materiais , Desenho de Aparelho Ortodôntico , Fios Ortodônticos , Aço Inoxidável , Propriedades de Superfície
8.
J Vasc Interv Radiol ; 31(11): 1874-1885, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33129433

RESUMO

PURPOSE: To assess the feasibility of inducing vascular occlusion by application of radiofrequency (RF) energy via conductive endovascular wires or baskets. MATERIALS AND METHODS: A retrievable nitinol basket and stainless steel guidewire with a platinum tip were evaluated as conductors for endovascular application of RF energy. Tissue-mimicking thermochromic gel phantoms that change color with heating were cast with 2-, 5-, and 7-mm-diameter lumens and filled with 37 oC saline. After ablation, the phantoms were sectioned, and the thermal footprints were evaluated. Six castrated male domestic swine underwent endovascular ablation using the basket in iliac arteries and guidewires in renal arteries. Post-procedural angiography was performed, and postmortem arterial segments were resected for histopathologic analysis. RESULTS: In the phantom, the depth of thermal change in the 5- and 7-mm lumens averaged 6.3 and 6.0 mm along the basket, respectively, and in the 2- and 5-mm lumens, the depth of thermal change averaged 1.9 and 0.5 mm along the wire, respectively. In the swine, RF energy delivery led to angiographic occlusion at 12 of 13 sites. Thermal injury and occlusion were similar at the proximal, middle, and distal basket treatment zone, whereas injury and occlusion decreased from the proximal to the distal end of the 5-cm wire treatment zone. CONCLUSIONS: Endovascular delivery of RF energy via a conductive basket in medium-sized arteries or a guidewire in small arteries led to acute angiographic and histologic occlusion. The potential to induce stasis might be useful in settings where rapid occlusion is desirable.


Assuntos
Procedimentos Endovasculares/instrumentação , Artéria Ilíaca/cirurgia , Ablação por Radiofrequência/instrumentação , Artéria Renal/cirurgia , Ligas , Animais , Condutividade Elétrica , Desenho de Equipamento , Estudos de Viabilidade , Temperatura Alta , Artéria Ilíaca/patologia , Masculino , Teste de Materiais , Modelos Animais , Orquiectomia , Platina , Artéria Renal/patologia , Aço Inoxidável , Sus scrofa
9.
Orthod Fr ; 91(3): 249-262, 2020 10 01.
Artigo em Francês | MEDLINE | ID: mdl-33146619

RESUMO

The use of self-ligating brackets has largely developed in orthodontic practice thanks to numerous advantages, including the reduction of frictional forces during sliding orthodontic mechanic. Faced with scientific evidence, this advantage still seems to be debatable. Our objective was to evaluate in vivo the frictional force of self-ligating brackets by searching for micro-morphological and chemical effects on the active slot surface, after phase of alignment-leveling and after a period in the mouth. 16 brackets from four commercial brands were selected (Damon®, In-Ovation®, Smart-clip® and Carriere®). These brackets were visualized using a scanning electron microscope (SEM) and dispersive energy spectroscopy to study their surface and initial chemical composition. After a period in the mouth, these brackets were debonded and evaluated with SEM, to search topographic and chemical changes in relation to the frictional forces. After a period of three months used for dental alignment, all the brackets show considerable changes in topographic and chemical properties related to frictional forces, with deposit of organic debris whose importance is related to the initial surface different from one manufacturer to another.


Assuntos
Braquetes Ortodônticos , Fios Ortodônticos , Ligas Dentárias , Análise do Estresse Dentário , Fricção , Teste de Materiais , Desenho de Aparelho Ortodôntico , Aço Inoxidável , Propriedades de Superfície
10.
Indian J Dent Res ; 31(4): 569-573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33107458

RESUMO

Aim: To evaluate the biodegradability of preformed stainless steel crowns at varying salivary pH and the cytotoxic effect of leached out elements on fibroblasts. Methodology: A total of 243 stainless steel crowns were selected and were divided into 3 groups (I, II, III) based on Ph of immersion media. The pH of samples in group I, II, III were 4.3, 5.5 and 6.3 with 81 crowns in each group. Each group has 9 samples with 8 crowns in each sample. All samples were immersed in polyethylene bottles containing 10ml of artificial saliva and incubated at 37°C for 4 weeks. All the samples were analyzed on 1,7,14 and 21 days by atomic absorption spectrophotometer for the quantitative assement of Ni, Cr and Fe. Fibroblast tissue culture was used to assess the cytotoxicity of the samples. Statistical Analysis: Analysis of variance. Results: Maximum release of Ni, Cr, Fe ions were observed at pH 4.3 followed by pH 5.5 and least release of ions were observed at pH 6.3 from SS crowns. The cytotoxic results showed that the least cell viability of cells was seen at pH 4.3. Conclusion: With decrease in pH, there is an increase in ion release from stainless steel crowns and the mean release of nickel, chromium and iron were very much below the average dietary intake. But the allergic manifestations of ions like nickel can't be ruled out.


Assuntos
Níquel , Aço Inoxidável , Cromo , Coroas , Concentração de Íons de Hidrogênio
11.
J Chromatogr A ; 1633: 461627, 2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33128970

RESUMO

A Poly (3,4-ethylenedioxothiophene) (PEDOT)/UiO-66 composite was electrodeposited on an etched stainless-steel wire as head-space solid-phase microextraction (HS-SPME) coating. A robust, well controlled thickness, and uniform coating of metal organic framework composites can be realized by the electrodeposited strategy. The incorporated UiO-66 not only enhanced the uniformity and stability of the composite coating, but also effectively decreased the stacking phenomenon of PEDOT and improved its extraction efficiency, which was over 100 times higher than that of the PEDOT coating without UiO-66. The composite coating was used to enrich seven types of volatile organic compounds (VOCs) in ion-exchange resins, including methyl cyclohexane, benzene, toluene, ortho-xylene, styrene, para-xylene and divinyl-benzene. The results of adsorption isotherm analysis showed that π stacking effect played dominant role between the composite coating and VOCs in the extraction process. The composite coating was characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared and thermogravimetric analysis, respectively. A determination method for seven kinds of VOCs was established by HS-SPME coupled with gas chromatography-flame ionization detection (GC-FID). Under the optimal experimental conditions, the detection linear range (LRs) was 0.09-100 ng mL-1, and the detection limit (LODs) was 0.03-0.06 ng mL-1 (S/N = 3). The method was applied for the migration detection of VOCs in four types of ion-exchange resin, which showed satisfactory recovery (84.5-117.2%).


Assuntos
Técnicas de Química Analítica/métodos , Estruturas Metalorgânicas/química , Polímeros/química , Tiofenos/química , Compostos Orgânicos Voláteis/isolamento & purificação , Adsorção , Benzeno/análise , Benzeno/isolamento & purificação , Cromatografia Gasosa , Ionização de Chama , Resinas de Troca Iônica/química , Limite de Detecção , Microextração em Fase Sólida , Aço Inoxidável/química , Tolueno/análise , Tolueno/isolamento & purificação , Compostos Orgânicos Voláteis/análise , Xilenos/análise , Xilenos/isolamento & purificação
12.
Water Sci Technol ; 82(5): 940-953, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33031072

RESUMO

Ag-Cu ions in cooling water may inhibit the activity of sulfate-reducing bacteria and therefore provide solutions to microbiologically induced corrosion (MIC) problems, mainly caused by Desulfovibrio sp. To investigate this, the MIC behavior of Desulfovibrio sp. on 316L stainless steel in terms of growth and extracellular polymeric substances (EPS) production was investigated in the presence of Ag-Cu ions. Laboratory-scale systems were set up with final concentrations of 0.13 ppm Ag and 0.3 ppm Cu ions, as they are the frequently used doses for cooling waters, and operated over 720 hours. The corrosion rate was evaluated by gravimetric assay, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses. The growth of Desulfovibrio sp. was assessed by bacterial counting and EPS production. Ag-Cu ions in the biofilm were assessed by inductively coupled plasma - optical emission spectrometry (ICP-OES) and EDS-elemental mapping analyses. It was concluded that the ion concentrations used caused an increase in EPS production, especially of protein. The corrosion rate of the metal by Desulfovibrio sp. in the presence of ions was detected as being 29 times higher than that in the sterile medium with the ions after 720 hours. The results suggested that Desulfovibrio sp. exhibited more corrosive behavior in the presence of non-toxic concentrations of Ag-Cu ions.


Assuntos
Desulfovibrio , Aço Inoxidável , Corrosão , Íons , Prata
13.
Int J Food Microbiol ; 335: 108856, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32961522

RESUMO

This study aimed to evaluate the sensitivity of heat-resistant molds isolated from spoiled thermally processed foods to antimicrobial compounds used for food industry sanitation. An ortho-phenylphenol-based smoke generator sanitizer, liquid chemical sanitizers (benzalkonium chloride, biguanide, iodine, peracetic acid, and sodium hypochlorite), and acidic and alkaline electrolyzed water were used against Aspergillus australensis (MB 2579; NFF 02), Aspergillus aureoluteus (NFC1), Paecilomyces fulvus (PFF 01), Paecilomyces niveus (PNT 01; PNDC 01; PNB1 01), and Paecilomyces variotii (PV 01; PV 01; PVCH 03). The fungal strains were exposed separately to liquid sanitizers and electrolyzed water in stainless steel discs for 15 min following the European Committee for Standardization (CEN) recommendations. Moreover, the fungal strains were exposed to the smoke generator sanitizer for 7 h following French protocol NF-T-72281. The best results of fungal inactivation were achieved when the highest concentration specified in the label of these sanitizers was tested. On the opposite, the lowest concentration specified in the label should be avoided since it was ineffective in most cases (94%). The ortho-phenyphenol-based smoke generator sanitizer and peracetic acid (1%) showed the best results of spore inactivation, while iodine and benzalkonium chloride achieved satisfactory results against the strains evaluated. Sodium hypochlorite and biguanide were ineffective against most of the fungi studied at all concentrations tested. Acidic and basic electrolyzed water was also ineffective to achieve the 3-log CFU reduction required in the concentrations tested. In general, Paecilomyces spp. was more sensitive than Aspergillus spp. against all sanitizers evaluated, whereas A. aureoluteus NFC1 was resistant to all agents and concentrations tested. The heat-resistant fungal strains showed varied sensitivity against the different agents. Notably, the two most effective commercial sanitizers against the heat-resistant strains were ineffective against the filamentous fungi recommended for sanitizer testing (A. brasiliensis ATCC 16404), which demonstrates the relevance of testing fungal isolates that cause spoilage to choose the most effective compound and obtain the best results of fungal control.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Desinfetantes/farmacologia , Paecilomyces/efeitos dos fármacos , Compostos de Benzalcônio/farmacologia , Compostos de Bifenilo/farmacologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Peróxido de Hidrogênio/farmacologia , Testes de Sensibilidade Microbiana , Ácido Peracético/farmacologia , Hipoclorito de Sódio/farmacologia , Aço Inoxidável
14.
Prog Orthod ; 21(1): 32, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32924097

RESUMO

BACKGROUND: The loss of third-order information in pre-adjusted brackets due to torsional play is a problem in clinical orthodontics. The aim of this study was to evaluate the impact of slot height, archwire height, width and edge bevel's radius on the torsional play for three brackets/archwire systems. METHODS: Ninety brackets with a 0.022 × 0.028 in. slot with McLaughlin-Bennett-Trevisi prescription from three different manufacturers were selected, and the slot's height and depth were measured using a profile projector. Sixty stainless-steel rectangular archwires from three different manufacturers were sectioned and observed with a SEM to measure their height, width, and radius of edge bevel. The recorded data were used to calculate the theoretical torsional play between different slot-archwire combinations. One-way ANOVA was used to compare the measurements within different bracket types and among different manufacturers. RESULTS: Slot height was usually oversized. Archwire's height was usually undersized, but oversized wires were also observed. The radius edge bevel was the most variable parameter. A certain degree of torsional play is always present that differs from one bracket type to another of the same producer and that can even be doubled from one manufacturer to another. CONCLUSIONS: Due to production tolerance, differences between the nominal values and the real dimensions of any components of a slot/archwire system are common. This results in a torsional play that limits torque expression. The archwire's edge bevel plays an important role in torque expression, and clearer information should be provided by the manufacturers regarding this aspect.


Assuntos
Braquetes Ortodônticos , Fios Ortodônticos , Desenho de Aparelho Ortodôntico , Aço Inoxidável , Torque
15.
Ann Vasc Surg ; 69: 400-412, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738387

RESUMO

BACKGROUND: To examine intraheartbeat displacements (IHD) and geometrical changes of endografts for abdominal aortic aneurysm repair over the course of years, defined as follow-up displacements (FUD), and to correlate them with computational fluid dynamics (CFD). Despite the widespread use of endovascular aneurysm repair (EVAR), we still know little about endograft behavior after deployment. METHODS: Two cases, treated with either expanded polytetrafluoroethylene on a nitinol stent frame (PI) or with woven polyester fabric sutured to a stainless-steel Z stent skeleton (PII), were submitted to dynamic computed tomography angiography at 1, 12, and 60 months after implantation. After segmentation, IHD were computed as displacements of the reconstructed surface with respect to the diastolic instant. Similarly, FUD were studied using imaging techniques that align temporal successive segmentations. In addition, numerical simulations for blood dynamics were performed to compute viscous forces, specifically wall shear stress and time-averaged wall shear stress (TAWSS). RESULTS: IHD analysis showed slight translations without deformation for the PI endograft with respect to the stiffer stainless-steel endograft behavior of PII. FUD showed in PI motion of the metallic struts mainly focused on the distal main body of the endograft and in the zone overlapping with iliac branches. In PII, we observed a huge FUD in the middle and inferior-anterior regions of the main body. CFD analysis revealed changes of velocity patterns associated with remodeling of the iliac zone for PI and of the main body region for PII, where flow impinges the lumen wall and progressively induces deformation of the endograft wires. Measurement of TAWSS demonstrated flow disturbances in the enlarged region correlated with displacement analysis. CONCLUSIONS: Image-based displacement analysis associated with CFD enabled very subtle evaluations of endograft behavior on different temporal scales. This kind of study could be helpful both for physicians, forecasting evolution during the life span of the endograft, and manufacturers, giving them useful information about endograft implant performance and design.


Assuntos
Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Técnicas de Imagem de Sincronização Cardíaca , Procedimentos Endovasculares/instrumentação , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Stents , Idoso , Ligas , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/fisiopatologia , Aortografia , Angiografia por Tomografia Computadorizada , Eletrocardiografia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Poliésteres , Politetrafluoretileno , Valor Preditivo dos Testes , Desenho de Prótese , Fluxo Sanguíneo Regional , Aço Inoxidável , Estresse Mecânico , Fatores de Tempo , Resultado do Tratamento
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(8): 551-554, 2020 Aug 09.
Artigo em Chinês | MEDLINE | ID: mdl-32842346

RESUMO

Deciduous caries and abnormal tooth development are common children's oral diseases which seriously harm the health of deciduous dentition, hinder the absorption of nutrients and affect the general growth and development. Caries of deciduous teeth progresses rapidly and can develop into rampant caries and other hard tissue diseases in a short time. The metal prefabricated crown is a stainless steel restoration for the treatment and repair of severe dental tissue damage in children. Its repair technique has certain operating procedures, requires specific equipments and materials, needs qualified dental clinicians to complete. The Society of Pediatric Dentistry, Chinese Stomatological Association organized experts to formulate the guideline of the clinical operation stainless steel crown restoration, so as to standardize the application of stainless steel crowns in the molar repair treatment of deciduous teeth such as caries in children and to further promote the application of the technique.


Assuntos
Cárie Dentária/terapia , Dente Decíduo , Criança , Coroas , Restauração Dentária Permanente , Humanos , Aço Inoxidável
17.
Bone Joint J ; 102-B(7_Supple_B): 116-121, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32600200

RESUMO

AIMS: This study aimed to determine if macrophages can attach and directly affect the oxide layers of 316L stainless steel, titanium alloy (Ti6Al4V), and cobalt-chromium-molybdenum alloy (CoCrMo) by releasing components of these alloys. METHODS: Murine peritoneal macrophages were cultured and placed on stainless steel, CoCrMo, and Ti6Al4V discs into a 96-well plate. Cells were activated with interferon gamma and lipopolysaccharide. Macrophages on stainless steel discs produced significantly more nitric oxide (NO) compared to their control counterparts after eight to ten days and remained elevated for the duration of the experiment. RESULTS: On stainless steel, both nonactivated and activated cell groups were shown to have a significant increase in metal ion release for Cr, Fe, and Ni (p < 0.001, p = 0.002, and p = 0.020 respectively) compared with medium only and showed macrophage-sized corrosive pits on the stainless steel surface. On titanium alloy discs there was a significant increase in aluminum (p < 0.001) among all groups compared with medium only. CONCLUSION: These results indicated that macrophages were able to attach to and affect the oxide surface of stainless steel and titanium alloy discs. Cite this article: Bone Joint J 2020;102-B(7 Supple B):116-121.


Assuntos
Prótese Articular , Macrófagos/química , Aço Inoxidável , Titânio , Vitálio , Ligas , Animais , Sobrevivência Celular , Cromo/análise , Meios de Cultura , Íons , Ferro/análise , Camundongos , Microscopia Eletrônica de Varredura , Níquel/análise , Óxido Nítrico/análise
18.
mSphere ; 5(4)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611701

RESUMO

Coronavirus disease 2019 (COVID-19) was first identified in China in late 2019 and is caused by newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies had reported the stability of SARS-CoV-2 in cell culture media and deposited onto surfaces under a limited set of environmental conditions. Here, we broadly investigated the effects of relative humidity, temperature, and droplet size on the stability of SARS-CoV-2 in a simulated clinically relevant matrix dried on nonporous surfaces. The results show that SARS-CoV-2 decayed more rapidly when either humidity or temperature was increased but that droplet volume (1 to 50 µl) and surface type (stainless steel, plastic, or nitrile glove) did not significantly impact decay rate. At room temperature (24°C), virus half-life ranged from 6.3 to 18.6 h depending on the relative humidity but was reduced to 1.0 to 8.9 h when the temperature was increased to 35°C. These findings suggest that a potential for fomite transmission may persist for hours to days in indoor environments and have implications for assessment of the risk posed by surface contamination in indoor environments.IMPORTANCE Mitigating the transmission of SARS-CoV-2 in clinical settings and public spaces is critically important to reduce the number of COVID-19 cases while effective vaccines and therapeutics are under development. SARS-CoV-2 transmission is thought to primarily occur through direct person-to-person transfer of infectious respiratory droplets or through aerosol-generating medical procedures. However, contact with contaminated surfaces may also play a significant role. In this context, understanding the factors contributing to SARS-CoV-2 persistence on surfaces will enable a more accurate estimation of the risk of contact transmission and inform mitigation strategies. To this end, we have developed a simple mathematical model that can be used to estimate virus decay on nonporous surfaces under a range of conditions and which may be utilized operationally to identify indoor environments in which the virus is most persistent.


Assuntos
Fômites/virologia , Umidade , Modelos Teóricos , Vírus da SARS/fisiologia , Temperatura , Inativação de Vírus , Poluição do Ar em Ambientes Fechados , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Meia-Vida , Humanos , Pandemias/prevenção & controle , Plásticos , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Porosidade , Saliva/química , Saliva/virologia , Aço Inoxidável , Propriedades de Superfície
19.
Int J Food Microbiol ; 333: 108780, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32682208

RESUMO

Several materials such as plastic, wood, cardboard or stainless steel are used as working surfaces or packaging in direct contact with foodstuffs. In food industries, the hygienic surface status is one of the criteria to product conform packaging as described in the European regulation ECR 1935/2004. Today in European Union, it exists one harmonized regulation specific for Food Contact material made of plastic called EU N°10/2011 (Anonymous 2011a). This regulation specifies that materials intended for safe foodstuff contact must not modify food characteristics in terms of chemical, microbiological and sensorial properties. This study aims to compare the survival and transfer of Penicillium expansum conidia and Escherichia coli cells from several materials to apples. Poplar, cardboards, newly manufactured plastic and reusable plastic specimens were artificially inoculated with both microorganisms, subsequently put in contact with apples and stored under realistic storage conditions. After incubation for up to 1 week, apples and specimens were analysed to assess the survival of the microorganisms and their transfer from materials to apples. While P. expansum survived and did not grow on any of the materials, E. coli mortality was observed after 1 h on wood and cardboard and after 1 week on both plastics. The proportion of microorganisms transferred was different according to the considered material. This transfer was lower than 1% for wood.


Assuntos
Escherichia coli/isolamento & purificação , Malus/microbiologia , Penicillium/isolamento & purificação , Plásticos/análise , Aço Inoxidável/análise , Madeira/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos
20.
Food Chem ; 333: 127450, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663749

RESUMO

The aged wine spirit is a beverage with great aromatic complexity. Their volatile compounds with odorant power coming from the distillate and from the wood used in its ageing, and the interactions that take place in the process, enhanced by oxygen, all contribute to this complexity. Due to time and cost inherent of ageing wine spirits in wooden barrels, research has sought to develop more sustainable alternatives to do it. In this context, the present study compares, the effect of traditional (wooden barrel) and alternative system (stainless steel tank with dipped staves and micro-oxygenation), on the odorant and sensory profile of a wine spirit, using Limousin oak and chestnut wood, after 12 months of ageing. The results suggest that the ageing process is accelerated by the alternative ageing technology and the chestnut wood, and the corresponding wine spirits presented characteristics of greater sensory evolution and strong wood compounds extraction.


Assuntos
Indústria de Processamento de Alimentos/métodos , Odorantes , Vinho , Madeira , Adulto , Aesculus , Idoso , Feminino , Indústria de Processamento de Alimentos/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes/análise , Oxigênio/química , Quercus , Aço Inoxidável , Fatores de Tempo , Compostos Orgânicos Voláteis/análise , Vinho/análise
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