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1.
Magn Reson Med ; 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33738824

RESUMO

PURPOSE: To present a reproducible methodology for building an anatomy mimicking phantom with targeted T1 and T2 contrast for use in quantitative magnetic resonance imaging. METHODS: We propose a reproducible method for creating high-resolution, quantitative slice phantoms. The phantoms are created using gels with different concentrations of NiCl2 and MnCl2 to achieve targeted T1 and T2 values. We describe a calibration method for accurately targeting anatomically realistic relaxation pairs. In addition, we developed a method of fabricating slice phantoms by extruding 3D printed walls on acrylic sheets. These procedures are combined to create a physical analog of the Brainweb digital phantom. RESULTS: With our method, we are able to target specific T1 /T2 values with less than 10% error. Additionally, our slice phantoms look realistic since their geometries are derived from anatomical data. CONCLUSION: Standardized and accurate tools for validating new techniques across sequences, platforms, and different imaging sites are important. Anatomy mimicking, multi-contrast phantoms designed with our procedures could be used for evaluating, testing, and verifying model-based methods.

2.
Aust Endod J ; 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720489

RESUMO

The aim of the study was to compare cyclic fatigue (CF) resistance of reciprocating and rotary glide path instruments in the presence of irrigation solutions at body temperature. CF resistance of 100 instruments (50 ProGlider and 50 WaveOne Gold Glider) was tested in sodium hypochlorite solutions alone (NaOCl) or in combination with etidronate (NaOCl/HEBP). The CF platform with a simulated canal (curvature = 60°/radius = 3 mm) was submerged in a temperature-controlled bath with the solutions kept at 37 ± 1°C controlled by a precision mercury glass thermometer. Instruments were actioned following manufacturer guidelines, and time to failure was recorded and compared among groups with Weibull analysis. Reciprocating glide path preparation instruments were more resistant to CF than rotary instruments in both irrigation solutions. The irrigation solution did not affect the mean life of ProGlider, but reciprocating instruments lasted significantly longer used in presence of NaOCl compared to NaOCl/HEBP.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33566296

RESUMO

The restrictions imposed on the use of formaldehyde in wood panel adhesives have been the driving force behind the development of formaldehyde-free resins for the manufacture of wood products. Considering as a boundary condition the idea that the use of fossil-based raw materials should be replaced by biological options, there is growing interest in the environmental assessment of different alternatives for soy-based adhesives, as possible options to replace commonly used synthetic resins. This report includes the environmental profiles of soy-based adhesives taking into account the life cycle assessment (LCA) methodology. In addition, in order to increase their potential to replace synthetic resins, a sensitivity analysis of the main contributors to environmental damage was performed, thus giving an open guide for further research and improvement. This study aims to provide innovative alternatives and new trends in the field of environmentally friendly bio-adhesives for the wood panel industry.

4.
Artigo em Esperanto | MEDLINE | ID: mdl-33434913

RESUMO

Introducción: Los trastornos genéticos que afectan la homeostasis del surfactante pulmonar son una causa importante del síndrome de dificultad respiratoria en el recién nacido a término y de enfermedad pulmonar intersticial difusa en niños. El transportador ABCA3 (ATP binding cassette A3) interviene en la producción normal del surfactante que recubre el interior de las paredes alveolares y funciona como agente tensioactivo. Caso clínico: Recién nacido a término que presentó dificultad respiratoria a los 3 días de vida y requirió ventilación mecánica. Los estudios para determinar otras causas de enfermedad pulmonar fueron negativos. Se realizó una biopsia de pulmón para realizar estudios de microscopía óptica y microscopía electrónica. Esta última mostró pequeños cuerpos lamelares anómalos, además de condensaciones electrodensas periféricas, características de las mutaciones del transportador ABCA3. Se inició tratamiento con pulsos de metilprednisolona, hidroxicloroquina, azitromicina y corticoides inhalados a dosis altas, y la respuesta clínica y radiológica fue favorable durante el seguimiento. Conclusiones: La correlación de las características clínicas y de las imágenes (tomografía y microscopía electrónica) puede ser útil para el diagnóstico de la disfunción del surfactante pulmonar, especialmente en los países de bajos y medianos recursos que no disponen de estudios genéticos para determinar las diferentes mutaciones del transportador ABCA3. Este es uno de los primeros casos reportados en Perú con respuesta adecuada al tratamiento y evolución favorable durante el seguimiento.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33166732

RESUMO

BACKGROUND: Nonpriority legume allergies, which include chickpea, pea, lentil, and lupine, are frequently implicated in severe allergic reactions. Yet, studies on public health knowledge and educational needs are near-absent. OBJECTIVE: To summarize what is known from the existing literature about nonpriority legume food allergy. METHODS: Eligible, original research articles reported on both nonpriority legume food allergy and 1 or more of prevalence, burden, food labeling information, or current education strategies. Screening was performed by 2 independent reviewers. Conflicts were discussed and if consensus could not be reached, a third reviewer was consulted. RESULTS: Of the 8976 titles identified, 47 were included subsequent to full-text screening. Most studies identified focused on prevalence, and were conducted in Europe, with additional studies from Asia, and North America. Although we defined burden quite broadly, few studies addressed the burden of nonpriority legume food allergens. Moreover, no studies addressed labeling or educational needs for these allergens. CONCLUSIONS: Our review of the literature found current research focused on the prevalence of nonpriority legume allergy with significant gaps regarding burden, allergen labeling, and education strategies. To this end, further research on these aspects of nonpriority legume allergy is warranted.

7.
Adv Mater ; : e2005970, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33179325

RESUMO

Human skin is equipped with slow adapting (SA) and fast adapting (FA) capabilities simultaneously. To mimic such functionalities, elaborately designed devices have been explored by integrating multiple sensing elements or adopting multimode sensing principles. However, the complicated fabrication, signal mismatch of different modules, complex operation, and high power-consumption hinder their widespread applications. Here, a new type of single-mode and self-powered mechanoreceptor that can mimic both SA and FA via seamless fusion of complementary while compatible potentiometric and triboelectric sensing principles is reported. The resultant potentiometric-triboelectric hybridized mechanoreceptor exhibits distinctive features that are hard to achieve via currently existing methods, including single-mode output (only voltage signal), greatly simplified operation (single-measurement setup), ultralow power-consumption (<1 nW), self-adaptive response behavior, and good capability for resolving complex stimuli. Diverse mechanical characteristics, including magnitude, duration, frequency, applying and releasing speed, can be well interpreted with this single-mode and self-powered mechanoreceptor. Its promising application for monitoring object manipulations with a soft robotic gripper is explored. Furthermore, the versatility of the mechanoreceptor for resolving complex stimuli in diverse daily scenarios is demonstrated. This work presents a new design that will significantly simplify the fabrication/operation and meanwhile boost the functionality/energy-efficiency of future electronic devices and smart systems.

8.
Sci Rep ; 10(1): 16543, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024141

RESUMO

Sensor data can be wirelessly transmitted from simple, battery-less tags using Radio Frequency Identification (RFID). RFID sensor tags consist of an antenna, a radio frequency integrated circuit chip (RFIC), and at least one sensor. An ideal tag can communicate over a long distance and be seamlessly integrated onto everyday objects. However, miniaturized antenna designs often have lower performance. Here we demonstrate compact, flexible sensor tags with read range comparable to that of conventional rigid tags. We compare fabrication techniques for flexible antennas and demonstrate that screen and stencil printing are both suitable for fabricating antennas; these different techniques are most useful at different points in the design cycle. We characterize two versions of flexible, screen printed folded dipoles and a meandered monopole operating in the 915 MHz band. Finally, we use these antennas to create passive sensor tags and demonstrate over the air communication of sensor data. These tags could be used to form a network of printed, flexible, passive, interactive sensor tags.

9.
Aust Endod J ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030288

RESUMO

The purpose of this study was to evaluate current trends in access cavity design and cleaning and shaping among endodontists. A survey was e-mailed to active members of the American Association of Endodontists. Data showed that most respondents used traditional (57%) or conservative (43%) access cavities; less than 1% reported using ultraconservative access cavities. A glide path was created by 93% of respondents; NaOCl was used as lubricant by 51% of respondents, while 28% used RC Prep, 9% used liquid EDTA, 7% used Glyde, and 2% did not use any lubricant. Most respondents used NaOCl at 5.25% or higher concentration. Smear layer was removed by 92% of endodontists. Apical gauging was mostly accomplished with hand files. Clinical preferences varied among surveyed endodontists and among different age groups. Currently, very few endodontists use ultraconservative access preparations. There was large variation among the respondents suggesting a possible need for quality guidelines.

10.
Reumatol. clín. (Barc.) ; 16(5,pt.1): 313-318, sept.-oct. 2020. tab
Artigo em Espanhol | IBECS | ID: ibc-195886

RESUMO

INTRODUCCIÓN: La arteritis de células gigantes (ACG) es una vasculitis que afecta a arterias de mediano y gran calibre. La biopsia de la arteria temporal es la técnica diagnóstica de elección. Atendiendo a la demanda asistencial que supone, pretendemos evaluar la utilidad de la ecografía Doppler en los pacientes con sospecha de ACG, su sensibilidad y especificidad como prueba diagnóstica y si puede suplir a la biopsia. MATERIALES Y MÉTODOS: Se ha realizado un estudio prospectivo de 57 pacientes entre febrero de 2015 y julio de 2016, que han sido diagnosticados con exploración mediante ecografía Doppler y biopsia de arteria temporal. RESULTADOS: Fueron incluidos 57 pacientes, de los cuales 3 fallecieron durante el seguimiento y una paciente fue excluida del estudio al negarse a la biopsia. Otros 21 pacientes fueron diagnosticados de ACG por un especialista reumatólogo tras un mínimo de 6 meses de seguimiento. Presentaron ecografía positiva 22 pacientes, de los cuales 8 fueron diagnosticados de ACG y 4 de polimialgia reumática. En nuestro estudio, la sensibilidad de la ecografía es del 42,6% y la especificidad es del 65,7%. Otros 19 pacientes presentaron biopsia positiva: todos ellos fueron diagnosticados de ACG. La biopsia presentó una sensibilidad de un 73,7% y una especificidad de un 100%. CONCLUSIONES: Según nuestro estudio, la utilidad de la ecografía es limitada y son necesarias nuevas investigaciones para determinar su papel en esta entidad


BACKGROUND: Giant cell arteritis (GCA) is a vasculitis that affects medium- and large-sized arteries. Temporal artery biopsy is the gold standard for diagnosis. In view of the high demand for temporal biopsies, the purpose of this study is to evaluate the usefulness of Doppler ultrasonography in patients with suspected giant cell arteritis, to determine its sensitivity and specificity as a diagnostic test and to determine whether it would be possible to substitute biopsy for ultrasonography. MATERIALS AND METHODS: A prospective study was undertaken including 57 patients from February 2015 to July 2016, who have undergone both ultrasonography and temporal biopsy. RESULTS: A total of 57 patients were included, 3of whom died during the follow-up, and a patient was excluded from the study when she refused to have the biopsy. Another 21 patients were diagnosed with GCA by a rheumatologist after a minimum of 6 months of follow-up and 22 patients had positive ultrasonography, 8 of whom were diagnosed with GCA and 4 with polymyalgia rheumatica. In our study, the sensitivity of ultrasonography was 42.6%, and the specificity was 65.7%. A total of 19 patients had a positive biopsy, all of them were diagnosed with GCA. In our study, the sensitivity of the biopsy was 73.7% and the specificity was 100%. CONCLUSIONS: In view of the data from our study, the usefulness of ultrasonography is questionable, and research about the role of ultrasonography in this disease should be further studied


Assuntos
Humanos , Masculino , Feminino , Idoso , Arterite de Células Gigantes/diagnóstico por imagem , Arterite de Células Gigantes/patologia , Biópsia , Ecocardiografia Doppler , Artérias Temporais/diagnóstico por imagem , Artérias Temporais/patologia , Sensibilidade e Especificidade , Estudos Prospectivos
12.
Sci Total Environ ; 738: 140357, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806374

RESUMO

The wood panel industry requires the introduction of more environmental-friendly adhesives due to the strict current regulations on formaldehyde-based emissions. The purpose of this study was to environmentally analyse the production of four different bio-adhesives as alternatives to the most conventional fossil resins used in the production of wood panels. The bio-adhesives proposed for analysis derived from different available renewable biopolymers such as protein (soy) and lignin (Kraft and Organosolv), as well as tannin. The production systems were evaluated from a cradle-to-gate perspective using the Life Cycle Assessment methodology, with the aim of identifying critical parameters and comparing them with fossil substitutes. Inventory data of bio-adhesives were modelled at large scale from lab scale experiments and completed with literature reports. Our results showed that the soy-based and tannin based bio-adhesive had an overall better profile than fossil resins, identifying the production of polyacrylamide for the former, and the production of condensed tannin and glyoxal for the latter, as the main environmental hotspots. In contrast, further research is required on the use of lignins, specifically because of the electricity requirements in the lignin glyoxalation stage (a process required for the functionalization of lignin). Sensitivity analyses were conduced on these key parameters suggesting that there is room for improvement.This study provides useful information for researchers and policy-makers on where to focus their activities with the aim of making the future of bio-adhesives more technically and environmentally favourable.


Assuntos
Adesivos , Madeira , Formaldeído , Indústrias , Lignina
13.
IEEE Trans Biomed Circuits Syst ; 14(4): 727-737, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32746342

RESUMO

In the past few years it has been demonstrated that electroencephalography (EEG) can be recorded from inside the ear (in-ear EEG). To open the door to low-profile earpieces as wearable brain-computer interfaces (BCIs), this work presents a practical in-ear EEG device based on multiple dry electrodes, a user-generic design, and a lightweight wireless interface for streaming data and device programming. The earpiece is designed for improved ear canal contact across a wide population of users and is fabricated in a low-cost and scalable manufacturing process based on standard techniques such as vacuum forming, plasma-treatment, and spray coating. A 2.5 × 2.5 cm2 wireless recording module is designed to record and stream data wirelessly to a host computer. Performance was evaluated on three human subjects over three months and compared with clinical-grade wet scalp EEG recordings. Recordings of spontaneous and evoked physiological signals, eye-blinks, alpha rhythm, and the auditory steady-state response (ASSR), are presented. This is the first wireless in-ear EEG to our knowledge to incorporate a dry multielectrode, user-generic design. The user-generic ear EEG recorded a mean alpha modulation of 2.17, outperforming the state-of-the-art in dry electrode in-ear EEG systems.

14.
Sci Adv ; 6(30): eaba1062, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32832659

RESUMO

Human skin perceives external mechanical stimuli by sensing the variation in the membrane potential of skin sensory cells. Many scientists have attempted to recreate skin functions and develop electronic skins (e-skins) based on active and passive sensing mechanisms. Inspired by the skin sensory behavior, we investigated materials and electronic devices that allow us to encode mechanical stimuli into potential differences measured between two electrodes, resulting in a potentiometric mechanotransduction mechanism. We present here a potentiometric mechanotransducer that is fabricated through an all-solution processing approach. This mechanotransducer shows ultralow-power consumption, highly tunable sensing behavior, and capability to detect both static and low-frequency dynamic mechanical stimuli. Furthermore, we developed two novel classes of sensing devices, including strain-insensitive sensors and single-electrode-mode e-skins, which are challenging to achieve using the existing methods. This mechanotransduction mechanism has broad impact on robotics, prosthetics, and health care by providing a much improved human-machine interface.

15.
Braz Oral Res ; 34: e069, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696911

RESUMO

The aim of this randomized clinical trial was to compare the occurrence and intensity of postoperative pain and analgesic intake after root canal treatment, using different root canal sealers. Sixty single-rooted teeth diagnosed with asymptomatic necrosis and apical periodontitis were randomly assigned to 3 experimental groups (n=20), according to the root canal sealer: AH Plus, Endofill or MTA Fillapex. Endodontic treatment was performed in two sessions, and calcium hydroxide was used as the intracanal dressing. Patients were instructed to record pain intensity as none, slight, moderate and severe. Scores from 1 to 4 were attributed to each level of pain after 24 h, 48 h and 7 days. The need for analgesic intake was also recorded. Differences in the incidence of postoperative pain and the need for an analgesic were analyzed using the chi-square test. Differences in pain intensity after treatment were analyzed using the ordinal (linear) chi-square test. No significant differences were detected among the groups in terms of either incidence or intensity of postoperative pain, or need for analgesic intake, at any timepoint (p>0.05). No pain was reported after 7 days. AH Plus, Endofill and MTA Fillapex used for filling root canals resulted in the same rate of postoperative pain and need for analgesic medication.


Assuntos
Cavidade Pulpar , Hidróxido de Cálcio , Resinas Epóxi , Humanos , Dor Pós-Operatória , Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Tratamento do Canal Radicular
16.
Int J Numer Method Biomed Eng ; 36(10): e3385, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32639658

RESUMO

Fluid dynamics generated by irrigation needles have not been deeply analyzed in root canal irregularities such as apical ramifications or isthmus where the cleaning capacity of irrigants might be compromised and hence the treatment outcome. The goal of this study was to compare the key irrigation parameters (flow pattern, irrigant velocity, apical pressure, and shear stress) between two irrigation needles and the additional effect of aspiration cannulas through computational fluid dynamics. A 3D-model consisting of two canals linked by an isthmus was modeled. The abovementioned needles irrigated the primary canal, whereas an aspiration cannula was located inside the secondary canal. Both the geometry definition and spatial discretization were carried out with ANSYS 16.2, through which six different simulations were performed: lateral exit (LE) needle, frontal exit (FE) needle, LE and cannula in crown (LEC), FE and cannula in crown (FEC), LE and cannula in middle third (LEM), FE and cannula in middle third (FEM). FE and FEM showed that the irrigation flow only passes through the isthmus in the most apical section (maximum irrigant velocity / shear stress = 8.44 m/s / 1628.44 Pa and 8.63 m/s / 1185.69 Pa, respectively). However, the remaining simulations showed the irrigation flow passing through the isthmus twice, through the most apical section first and through the upper part of the isthmus later (maximum irrigant velocity / shear stress = 8.48 m/s / 1298.24 Pa (LE), 8.61 m/s / 1261.36 Pa (LEM), 8.61 m/s / 1355.24 Pa (LEC), 8.59 m/s / 1256.87 Pa (FEC)). Furthermore, the highest velocity values were detected when aspiration cannulas were added.

17.
Dent J (Basel) ; 8(3)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32645948

RESUMO

The objective of this prospective study was to assess tooth-related factors that play a role in the incidence of postoperative pain (PP) and determining if procedural errors influence PP occurrence. A total of 442 patients referred for root canal treatment met the inclusion criteria and were included in this prospective study. The same protocol was used in all root canal treatments. Patient, tooth, treatment related factors and the occurrence of procedural errors were registered. Incidence and intensity of PP was assessed at 24 and 48 h by telephonic interview and in person seven and 15 days after treatment. A logistic and ordinal regression analysis was used to assess the role of patient, tooth and treatment related factors in the incidence and intensity of PP, respectively. Preoperative and intraoperative factors differently affected the incidence of PP at the different time intervals. The presence of procedural errors did not significantly influence PP occurrence. The presence of preoperative pain and the need of additional anesthesia during treatment were associated with higher incidence of PP 24 and 48 h after treatment; the extent of apical enlargement played a significant role in the presence of PP after seven days of treatment; and the excessive occlusal load induced by the absence of a contralateral tooth was the only factor related to the maintenance of PP up to 15 days. In conclusion, the presence of preoperative pain, the need of additional anesthesia during treatment, the extent of apical enlargement and the excessive occlusal load induced by the absence of a contralateral tooth were related to a higher incidence of PP.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32604943

RESUMO

Zika virus infection during pregnancy is a cause of congenital brain abnormalities. Its consequences for pregnancies have made governments and both national and international agencies issue advice and recommendations to women. This study was designed to understand the impacts of Zika on women who were less directly affected and less vulnerable to Zika. Women were recruited from various locations in Brazil, Puerto Rico, and the United States. Data were collected through semi-structured interviews and analyzed using thematic analysis. Women perceived that public health systems placed an unfair responsibility for preventing health complications from Zika onto women who had limited ability to do so. They also stated that the measures recommended to them were invasive, while creating the perception that women were the sole determinant of whether they contracted Zika. The results indicate that women with higher levels of education understood the limitations of the information, government actions, and medical care they received, which ended up producing higher levels of anguish and worry. Gender inequality and discrimination must be recognized and rendered visible in the public health emergency response. The social effects of the epidemic affected women more than had been thought before and at deeper emotional levels.


Assuntos
Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Adaptação Psicológica , Adulto , Brasil/epidemiologia , Feminino , Humanos , Gravidez , Porto Rico/epidemiologia , Estados Unidos , Adulto Jovem , Infecção por Zika virus/epidemiologia
19.
ACS Appl Mater Interfaces ; 12(28): 31687-31695, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32543852

RESUMO

The availability of transparent conductive thin films that exhibit mechanical flexibility and are adapted to low-cost and large-area fabrication is a major obstacle for high-performance flexible thin-film optoelectronics. Here, by combining printing, thin-film deposition, and wet-etching processes, interconnected transparent metal micromesh (TMM) electrodes are reported. Blade-coating is used to generate self-assembled polymer micromesh networks on flexible substrates. The network structures are subsequently converted into conductive metal networks. As-fabricated TMM films display a surface roughness of around 20 nm with thickness down to 50 nm. A transmittance of 86% and a conductance of 80 Ω sq-1 are achieved at the described optimal blade-coating suspension concentration. The electrodes show mechanical flexibility with no conductivity degradation with the smallest bending radius of 1 mm or at repeated bending over 3000 cycles at a bending radius of 15 mm. We successfully demonstrate organic light-emitting diodes (OLEDs) using TMM electrodes via the blade-coating technique. The printed OLEDs have a low turn-on voltage of 3.4 V and can achieve a luminance of over 4000 cd/m2 at 6.5 V. At a luminance of 100 cd/m2, the OLEDs show a current density of 7.6 mA/cm2, an external quantum efficiency (EQE) of 3.6%, and a luminous efficacy of 1.4 lm/W.

20.
BMC Pharmacol Toxicol ; 21(1): 35, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32434548

RESUMO

BACKGROUND: Acute pancreatitis is a rare but recognised complication of clozapine leading to termination of treatment. CASE PRESENTATION: We present the case of a 39-year-old man with treatment-resistant schizoaffective disorder and a history of recurrent acute pancreatitis attributed to clozapine. After 15 years of unremitting symptoms with disruptive and aggressive behaviour, he was admitted for a clozapine rechallenge. Despite experiencing two further episodes of acute pancreatitis during clozapine treatment that led to its temporary withdrawal, clozapine was successfully re-established under gastroenterology consultation with close monitoring which resulted in progressively marked improvement of his mental state. CONCLUSIONS: This case demonstrates that patients who develop pancreatitis during clozapine treatment may be cautiously rechallenged with specialist gastroenterology support.

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