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1.
ACS Appl Mater Interfaces ; 16(11): 13869-13881, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38466181

RESUMO

Poly(ethylene glycol) methyl ether methacrylate polymer networks (PEO-based networks), with or without anionic bis(trifluoromethanesulfonyl)imide (TFSI)-grafted groups, are promising electrolytes for Li-metal all solid-state batteries. Nevertheless, there is a need to enhance our current understanding of the physicochemical characteristics of these polymer networks to meet the mechanical and ionic conductivity property requirements for Li battery electrolyte materials. To address this challenge, our goal is to investigate the impact of the cross-linking density of the PEO-based network and the ethylene oxide/lithium ratio on mechanical properties (such as glass transition temperature and storage modulus) and ionic conductivity. We have synthesized a series of cross-linked PEO-based polymers (si-SPE for single ion solid polymer electrolyte) via solvent-free radical copolymerization. These polymers are synthesized by using commercially available lithium 3-[(trifluoromethane)sulfonamidosulfonyl]propyl methacrylate (LiMTFSI), poly(ethylene glycol)methyl ether methacrylate (PEGM), and [poly(ethylene glycol) dimethacrylate] (PEGDM). In addition, we have synthesized a series of cross-linked PEO-based polymers (SPE for solid polymer electrolyte) using LiTFSI as the ionic species. Most of the resulting polymer films are amorphous, self-standing, flexible, homogeneous, and thermally stable. Interestingly, our research has revealed a correlation between ionic conductivity and mechanical properties in both the SPE and si-SPE series. Ionic conductivity increases as glass transition temperature, α relaxation temperature, and storage modulus decrease, suggesting that Li+ transport is influenced by polymer chain flexibility and Li+/EO interaction.

2.
Small ; 20(12): e2307565, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946670

RESUMO

Liquid crystal elastomers (LCEs) with promising applications in the field of actuators and soft robotics are reported. However, most of them are activated by external heating or light illumination. The examples of electroactive LCEs are still limited; moreover, they are monofunctional with one type of deformation (bending or contraction). Here, the study reports on trilayer electroactive LCE (eLCE) by intimate combination of LCE and ionic electroactive polymer device (i-EAD). This eLCE is bi-functional and can perform either bending or contractile deformations by the control of the low-voltage stimulation. By applying a voltage of ±2 V at 0.1 Hz, the redox behavior and associated ionic motion provide a bending strain difference of 0.80%. Besides, by applying a voltage of ±6 V at 10 Hz, the ionic current-induced Joule heating triggers the muscle-like linear contraction with 20% strain for eLCE without load. With load, eLCE can lift a weight of 270 times of eLCE-actuator weight, while keeping 20% strain and affording 5.38 kJ·m-3 work capacity. This approach of combining two smart polymer technologies (LCE and i-EAD) in a single device is promising for the development of smart materials with multiple degrees of freedom in soft robotics, electronic devices, and sensors.

3.
Environ Sci Pollut Res Int ; 30(38): 89293-89310, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37452243

RESUMO

The dyke system plays a vital role in cultivating rice intensively in the Vietnamese Mekong Delta, which protects rice paddy fields from annual floods. This study aimed to examine whether the full-dyke system (FD, which restricts water exchange for a long time) can cause degradation of surface water quality and reduction in benthic invertebrate biodiversity. The surface water quality and benthic invertebrate community were compared between the FD and semi-dyke systems (SD, which permits water exchange during flooding season) using a large number of samples collected seasonally in 2019. The results showed that the surface water quality within the FD system had significantly higher concentrations of TSS, COD, BOD5, N-NO3-, N-TKN, P-PO43-, and TP than compared to the SD system (p < 0.05), indicating greater pollution levels. The benthic invertebrate community was less diverse in the FD system than in the SD system. Only 17 species (belonging to 4 families) were detected in the FD system, and 30 species (belonging to 5 families) were detected in the SD system. The benthic invertebrate community structure changes and biodiversity loss were associated with degraded water quality. The P-PO43- and TP parameters were negatively correlated with the number of species, density, and biomass in the FD system and with the Shannon-Wiener (H') index in the SD system. In conclusion, the FD system has been degrading water quality and causing biodiversity loss.


Assuntos
Invertebrados , Rios , Humanos , Animais , Vietnã , Rios/química , Invertebrados/química , Qualidade da Água , Biodiversidade
4.
RSC Adv ; 13(10): 6656-6667, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36860526

RESUMO

The growing demand for flexible, stretchable, and wearable devices has boosted the development of ionogels used as polymer electrolytes. Developing healable ionogels based on vitrimer chemistry is a promising approach to improve their lifetimes as these materials are usually subjected to repeated deformation during functioning and are susceptible to damage. In this work, we reported in the first place the preparation of polythioether vitrimer networks based on the not extensively studied associative S-transalkylation exchange reaction using thiol-ene Michael addition. Thanks to the exchange reaction of sulfonium salts with thioether nucleophiles, these materials demonstrated vitrimer properties such as healing and stress relaxation. The fabrication of dynamic polythioether ionogels was then demonstrated by loading 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMIM triflate) within the polymer network. The resulting ionogels exhibited Young's modulus of 0.9 MPa and ionic conductivities in the order of 10-4 S cm-1 at room temperature. It has been found that adding ionic liquids (ILs) changes the dynamic properties of the systems, most likely due to a dilution effect of the dynamic functions by the IL but also due to a screening effect of the alkyl sulfonium OBrs-couple by the ions of the IL itself. To the best of our knowledge, these are the first vitrimer ionogels based on an S-transalkylation exchange reaction. While the addition of ILs resulted in less efficient dynamic healing at a given temperature, these ionogels can provide materials with more dimensional stability at application temperatures and can potentially pave the way for the development of tunable dynamic ionogels for flexible electronics with a longer lifespan.

5.
ACS Appl Polym Mater ; 5(1): 529-541, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36686061

RESUMO

The growing demand for all-solid flexible, stretchable, and wearable devices has boosted the need for liquid-free and stretchable ionoelastomers. These ionic conducting materials are subjected to repeated deformations during functioning, making them susceptible to damage. Thus, imparting cross-linked materials with healing ability seems particularly promising to improve their durability. Here, a polymeric ionic liquid (PIL) bearing allyl functional groups was synthesized based on the quaternization of N-allylimidazole with a copolymer rubber of poly(epichlorohydrin) and poly(ethylene oxide) (PEO). The resulting PIL was then cross-linked with dynamic boronic ester cross-linkers 2,2'-(1,4-Phenylene)-bis[4-mercaptan-1,3,2-dioxaborolane] (BDB) through thiol-ene "click" photoaddition. PEO dangling chains were additionally introduced for acting as free volume enhancers. The properties of the resulting all-solid PIL networks were investigated by tuning dynamic cross-linkers and dangling chain contents. Adjusting the cross-linker and dangling chain quantities yielded soft (0.2 MPa), stretchable (300%), and highly conducting ionoelastomers (1.6 × 10-5 S·cm-1 at 30 °C). The associative exchange reaction between BDB endowed these materials with vitrimer properties such as healing and recyclability. The recycled materials were able to retain their original mechanical properties and ionic conductivity. These healable PIL networks display a great potential for applications requiring solid electrolytes with high ionic conductivity, healing ability, and reprocessability.

6.
Plants (Basel) ; 11(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36297818

RESUMO

Capsicum (Capsicum annuum L.) belongs to the Solanaceae family and is an economically important vegetable crop. However, the crop is very sensitive to adverse weather conditions such as high temperatures and excessive sunlight, which cause flower and young fruit to drop and sunscald to mature fruits. Using protected cultivation such as shade covers or net houses is a feasible agronomic approach to protect the crop from high light intensity, which increases plant growth, reduces fruit damage, and increases marketable fruit yield and quality. Low-cost protected cropping options such as fixed-roof net houses have proved cost-effective and suitable for fruiting vegetable production in semi-arid climatic regions. However, this structure type is unable to protect the crops from rainfall, is prone to cyclone damage and is inflexible to accommodate various vegetable crops which have different requirements for healthy and productive growth. This study was conducted in Carnarvon, which has semi-arid climatic conditions and is a key horticultural district of Western Australia, to compare the Retractable Roof Production System (RRPS) and open field (OF) conditions in the production of capsicum. The data showed that the RRPS modified the internal light, temperature and humidity in favour of the capsicum crop. The RRPS-grown capsicum had higher plant height and lower canopy temperature on hot days than those in the OF. The mean marketable fruit yield of capsicum varieties grown in the RRPS was significantly higher than those in the OF with fruit yields of 97 t ha-1 and 39.1 t ha-1, respectively, but the fruit quality remained unchanged. Overall, the data suggest that the RRPS altered the internal microenvironment and enhanced capsicum crop growth, physiology and fruit yield by setting climatic parameters to automatically control the opening and closing of the roof, the insect net and side curtains, and activation of the fogging system. The future perspective of the deployment of RRPS for capsicum production under climatic conditions in Carnarvon was also discussed.

7.
Gels ; 8(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35735725

RESUMO

Ionogels are solid polymer gel networks loaded with ionic liquid (IL) percolating throughout each other, giving rise to ionically conducting solid electrolytes. They combine the mechanical properties of polymer networks with the ionic conductivity, non-volatility, and non-flammability of ILs. In the frame of their applications in electrochemical-based flexible electronics, ionogels are usually subjected to repeated deformation, making them susceptible to damage. It appears critical to devise a simple and effective strategy to improve their durability and lifespan by imparting them with healing ability through vitrimer chemistry. In this work, we report the original in situ synthesis of polythioether (PTE)-based vitrimer ionogels using fast photopolymerization through thiol-acrylate Michael addition. PTE-based vitrimer was prepared with a constant amount of the trithiol crosslinker and varied proportions of static dithiol spacers and dynamic chain extender BDB containing dynamic exchangeable boronic ester groups. The dynamic ionogels were prepared using 50 wt% of either 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide or 1-Ethyl-3-methylimidazolium trifluoromethanesulfonate, both of which were selected for their high ionic conductivity. They are completely amorphous (Tg below -30 °C), suggesting they can be used at low temperatures. They are stretchable with an elongation at break around 60%, soft with Young's modulus between 0.4 and 0.6 MPa, and they have high ionic conductivities for solid state electrolytes in the order of 10-4 S·cm-1 at room temperature. They display dynamic properties typical of the vitrimer network, such as stress relaxation and healing, retained despite the large quantity of IL. The design concept illustrated in this work further enlarges the library of vitrimer ionogels and could potentially open a new path for the development of more sustainable, flexible electrochemical-based electronics with extended service life through repair or reprocessing.

8.
Science ; 376(6592): 502-507, 2022 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-35482868

RESUMO

The human somatosensory network relies on ionic currents to sense, transmit, and process tactile information. We investigate hydrogels that similarly transduce pressure into ionic currents, forming a piezoionic skin. As in rapid- and slow-adapting mechanoreceptors, piezoionic currents can vary widely in duration, from milliseconds to hundreds of seconds. These currents are shown to elicit direct neuromodulation and muscle excitation, suggesting a path toward bionic sensory interfaces. The signal magnitude and duration depend on cationic and anionic mobility differences. Patterned hydrogel films with gradients of fixed charge provide voltage offsets akin to cell potentials. The combined effects enable the creation of self-powered and ultrasoft piezoionic mechanoreceptors that generate a charge density four to six orders of magnitude higher than those of triboelectric and piezoelectric devices.


Assuntos
Hidrogéis , Mecanorreceptores , Humanos , Fenômenos Mecânicos , Pele , Tato/fisiologia
9.
Australas J Ageing ; 41(2): e122-e130, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34792256

RESUMO

OBJECTIVE: To investigate the prevalence and factors associated with frailty in rural and urban older outpatients in Vietnam. METHODS: This cross-sectional study included 1084 outpatients (aged ≥60 years; mean age 71.7 ± 7.4 years; female 65%) from rural (n = 600) and urban (n = 484) geriatric clinics from December 2019 to July 2020. Frailty was assessed using Fried frailty phenotype. Factors associated with frailty were assessed using logistic regression. RESULTS: Overall, frailty prevalence was 28% (rural, 26%; urban, 30%; p = 0.220). Factors associated with frailty were older age (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.13-1.20, p < 0.001), being underweight (OR 1.88, 95% CI 1.10-3.27, p = 0.025) and limitations in activities of daily living (ADLs) (OR 6.04, 95% CI 1.63-22.41, p = 0.007) and instrumental ADLs (OR 5.83, 95% CI 3.74-9.08, p < 0.001). Higher education (OR 0.47, 95% CI 0.29-0.76, p = 0.002) and productive work (OR 0.39, 95% CI 0.21-0.71, p = 0.002) were protective factors against frailty. CONCLUSIONS: In Vietnam, the prevalence of frailty in older outpatients was 28%, though not significantly different between urban and rural areas. Older age, being underweight and limitations in functional status can increase the odds of frailty, but higher education and productive work can reduce the odds of frailty.


Assuntos
Fragilidade , Atividades Cotidianas , Idoso , Estudos Transversais , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Prevalência , Magreza/complicações , Magreza/diagnóstico , Magreza/epidemiologia
10.
Soft Matter ; 17(48): 10786-10805, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34859250

RESUMO

Electroactive polymers based on dielectric elastomers are stretchable and compressible capacitors that can act as transducers between electrical and mechanical energies. Depending on the targeted application, soft actuators, sensors or mechanical-energy harvesters can be developed. Compared with conventional technologies, they present a promising combination of properties such as being soft, silent, light and miniaturizable. Most of the research on dielectric elastomer actuators has focused on obtaining the highest strain, either from technological solutions using commercially available materials or through the development of new materials. It is commonly accepted that a high electrical breakdown field, a low Young's modulus and a high dielectric constant are targets. However, the interdependency of these properties makes the evaluation and comparison of these materials complex. In addition, dielectric elastomers can suffer from electromechanical instability, which amplifies their complexity. The scope of this review is to tackle these difficulties. Thus, first, two physical parameters are introduced, one related to the energy converted by the dielectric elastomer and another to its electromechanical stability. These numbers are then used to compare dielectric elastomers according to a general and rational methodology considering their physicochemical and electromechanical properties. Based on this methodology, different families of commercially available dielectric elastomers are first analyzed. Then, different polymer modification methods are presented, and the resulting modified elastomers are screened. Finally, we conclude on the trends enabling the choice of the most suitable modification procedure to obtain the desired elastomer. From this review work, we would like to contribute to affording a quick identification method, including a graphic representation, to evaluate and develop the dielectric materials that are suitable for a desired actuator.

11.
Materials (Basel) ; 15(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35009162

RESUMO

Nowadays, thermal regulation of the indoor environment is mandatory to reduce greenhouse gas emissions. The incorporation of Phase Change Materials (PCMs) and especially solid-solid PCMs (s/s PCMs) into building materials can be a major step forward in reducing energy consumption. Such materials are used for their high latent heat to save and release heat during phase change. To integrate these products in the fabrication of cementitious materials, it is essential to predict their influence on the rheological behaviour of construction materials. In this work, rheological measurements were carried out on composite suspensions made of cement or mortar plus s/s PCMs. Results showed that the fitting of the Herschel-Bulkley model with a constant value of flow exponent was reliable. The s/s PCMs influenced the consistency and the yield strength values, with the yield strength value being only slightly affected. The adaptation of an existing viscosity model is proposed to predict the consistency value of suspensions. Finally, an innovative approach to predict the flow behaviour is proposed and we highlight the research needs to mainstream the use of s/s PCMs in construction materials.

12.
ACS Omega ; 5(25): 15229-15239, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32637796

RESUMO

In this study, cellulose extracted from straw was modified using N(4)-morpholinothiosemicarbazide to generate a novel adsorbent as a chelate-complex-based material. The effects of pH, time, temperature, and mass ratios of KIO4: cellulose on the yield of the oxidation were analyzed using iodometric titration and photometric methods. The accuracy and precision of the above two methods were evaluated using Student and Fisher statistical distribution. The structure of the material was characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and Brunauer-Emmett-Teller surface area analysis. The kinetic order of Ni(II) adsorption was dependent on the concentration of Ni(II). The surface response design enabled to optimize the condition for Ni(II) adsorption at 58 °C, pH of 4.98, within 106 min. The maximum Ni(II) adsorption capacity was 90 mg g-1. This kind of adsorbent can be reused at least five times without a significant decrease in its adsorption efficiency.

13.
Plants (Basel) ; 9(7)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610615

RESUMO

Genetically diverse plant germplasm stored in ex-situ genebanks are excellent resources for breeding new high yielding and sustainable crop varieties to ensure future food security. Novel alleles have been discovered through routine genebank activities such as seed regeneration and characterization, with subsequent utilization providing significant genetic gains and improvements for the selection of favorable traits, including yield, biotic, and abiotic resistance. Although some genebanks have implemented cost-effective genotyping technologies through advances in DNA technology, the adoption of modern phenotyping is lagging. The introduction of advanced phenotyping technologies in recent decades has provided genebank scientists with time and cost-effective screening tools to obtain valuable phenotypic data for more traits on large germplasm collections during routine activities. The utilization of these phenotyping tools, coupled with high-throughput genotyping, will accelerate the use of genetic resources and fast-track the development of more resilient food crops for the future. In this review, we highlight current digital phenotyping methods that can capture traits during annual seed regeneration to enrich genebank phenotypic datasets. Next, we describe strategies for the collection and use of phenotypic data of specific traits for downstream research using high-throughput phenotyping technology. Finally, we examine the challenges and future perspectives of genebank phenomics.

14.
Front Plant Sci ; 10: 1372, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772563

RESUMO

Nitrogen use efficiency (NUE) in crops is generally low, with more than 60% of applied nitrogen (N) being lost to the environment, which increases production costs and affects ecosystems and human habitats. To overcome these issues, the breeding of crop varieties with improved NUE is needed, requiring efficient phenotyping methods along with molecular and genetic approaches. To develop an effective phenotypic screening method, experiments on wheat varieties under various N levels were conducted in the automated phenotyping platform at Plant Phenomics Victoria, Horsham. The results from the initial experiment showed that two relative N levels-5 mM and 20 mM, designated as low and optimum N, respectively-were ideal to screen a diverse range of wheat germplasm for NUE on the automated imaging phenotyping platform. In the second experiment, estimated plant parameters such as shoot biomass and top-view area, derived from digital images, showed high correlations with phenotypic traits such as shoot biomass and leaf area seven weeks after sowing, indicating that they could be used as surrogate measures of the latter. Plant growth analysis confirmed that the estimated plant parameters from the vegetative linear growth phase determined by the "broken-stick" model could effectively differentiate the performance of wheat varieties for NUE. Based on this study, vegetative phenotypic screens should focus on selecting wheat varieties under low N conditions, which were highly correlated with biomass and grain yield at harvest. Analysis indicated a relationship between controlled and field conditions for the same varieties, suggesting that greenhouse screens could be used to prioritise a higher value germplasm for subsequent field studies. Overall, our results showed that this phenotypic screening method is highly applicable and can be applied for the identification of N-efficient wheat germplasm at the vegetative growth phase.

15.
PLoS One ; 14(6): e0217701, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31237921

RESUMO

BACKGROUND: The last international consensus on the management of type 2 diabetes (T2D) recommends SGLT-2 inhibitors or GLP-1 agonists for patients with clinical cardiovascular (CV) disease; metformin remains the first-line glucose lowering medication. Last studies suggested beneficial effects of SGLT-2 inhibitors or GLP-1 agonists compared to DPP-4 inhibitors, in secondary CV prevention. Recently, a potential benefit of SGLT-2 inhibitors in primary CV prevention also has been suggested. However, no comparison of all the new and the old hypoglycemic drugs is available on CV outcomes. We aimed to compare the effects of old and new hypoglycemic drugs in T2D, on major adverse cardiovascular events (MACE) and mortality. METHODS AND FINDINGS: We conducted a systematic review and network meta-analysis of clinical trials. Randomized trials, blinded or not, assessing contemporary hypoglycemic drugs on mortality or MACE in patients with T2D, were searched for in Medline, the Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov. References screening and data extraction were done by multiple observers. Each drug was analyzed according to its therapeutic class. A random Bayesian network meta-analysis model was used. The primary outcomes were overall mortality, cardiovascular mortality, and MACE. Severe adverse events and severe hypoglycemia were also recorded. 175,966 patients in 34 trials from 1970 to 2018 were included. No trials evaluating glinides or alpha glucosidase inhibitors were found. 17 trials included a majority of patients with previous cardiovascular history, 16 trials a majority of patients without. Compared to control, SGLT-2 inhibitors were associated with a decreased risk of overall mortality (OR = 0.84 [95% CrI: 0.74; 0.95]), SGLT-2 inhibitors and GLP-1 agonists with a decreased risk of MACE (OR = 0.89 [95% CrI: 0.81; 0.98] and OR = 0.88 [95% CrI: 0.81; 0.95], respectively). Compared to DPP-4 inhibitors, SGLT-2 inhibitors were associated with a decreased risk of overall mortality (OR = 0.82 [95% CrI: 0.69; 0.98]), GLP-1 agonists with a decreased risk of MACE (OR = 0.88 [95% CrI: 0.79; 0.99]). Insulin was also associated with an increased risk of MACE compared to GLP-1 agonists (OR = 1.19 [95% CrI: 1.01; 1.42]). Insulin and sulfonylureas were associated with an increased risk of severe hypoglycemia. In the trials including a majority of patients without previous CV history, the comparisons of SGLT-2 inhibitors, metformin and control did not showed significant differences on primary outcomes. We limited our analysis at the therapeutic class level. CONCLUSIONS: SGLT-2 inhibitors and GLP-1 agonists have the most beneficial effects, especially in T2D patients with previous CV diseases. Direct comparisons of SGLT-2 inhibitors, GLP-1 agonists and metformin are needed, notably in primary CV prevention. TRIAL REGISTRATION: PROSPERO CRD42016043823.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Idoso , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
16.
Int J Dent ; 2019: 2453469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31933643

RESUMO

INTRODUCTION: Cone-beam computed tomography (CBCT) is considered to be the most informative radiographic method for pre- and postoperative analysis of the maxillary anatomy and for avoiding further complication. Canalis sinuosus is one of such structures that damage can go along with bleeding and neurological symptomatology. The aim of the study was to investigate radiological and morphometric features of the canalis sinuosus in Russian population using CBCT technique. MATERIALS AND METHODS: 150 CBCT scans of 61 males and 89 females aged from 24 to 80 years were retrospectively studied with different slice thickness and evaluated with regards to prevalence and diameter among age and gender groups in Russia. RESULTS: CS prevalence in this study was 67%, and CS was most frequently presented in the lateral incisor region (33.5%). Women showed statistically higher CS prevalence (p < 0.01) than the male group, and there was no statistically significant difference observed between occurrence and localization of CS and age groups. CONCLUSION: CBCT examination demonstrated good diagnostic efficiency in CS visualization, and the CS may have variations on its location and prevalence with statistically significant differences between the gender group and without significant differences among age groups and can depend on the population.

17.
Radiat Prot Dosimetry ; 182(3): 352-358, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590847

RESUMO

The purpose of this study was to validate a novel approach to estimating effective dose (E) in 'fast-kV switch dual energy computed tomography' using MOSFET detectors. The effective energy of the combined dual energy environment was characterized with the dual energy CT scanner and then MOSFETs were calibrated matching to the effective energy of the dual energy CT beam with a conventional CT beam. The calibration method was then experimentally validated by comparing the dose between MOSFET and an ion chamber (IC) using a standard CTDI body phantom. The measured doses of the MOSFET and IC were 17.1 mGy ± 3.8% and 17.1 mGy ± 0.4%, respectively. To measure organ doses, an adult anthropomorphic phantom loaded with 18 MOSFET detectors was scanned using a standard fast-kV switch dual energy abdomen/pelvis CT protocol. E was calculated by applying ICRP 103 tissue weighting factors as well as partial volume correction factors for organs that were not completely covered by the protocol field-of-view. E from the dual energy abdomen/pelvis CT was calculated to be 17.8 mSv ± 11.6%. This calculation was then compared to E from dose length product method, which yielded 14.62 mSv.


Assuntos
Pelve/diagnóstico por imagem , Imagens de Fantasmas , Radiografia Abdominal/métodos , Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Carga Corporal (Radioterapia) , Calibragem , Humanos , Doses de Radiação
18.
PLoS One ; 13(11): e0207788, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30452470

RESUMO

Early vigour of seedlings is a beneficial trait of field pea (Pisum sativum L.) that contributes to weed control, water use efficiency and is likely to contribute to yield under certain environments. Although breeding is considered the most effective approach to improve early vigour of field pea, the absence of a robust and high-throughput phenotyping tool to dissect this complex trait is currently a major obstacle of genetic improvement programs to address this issue. To develop this tool, separate trials on 44 genetically diverse field pea genotypes were conducted in the automated plant phenotyping platform of Plant Phenomics Victoria, Horsham and in the field, respectively. High correlation between estimated plant parameters derived from the automated phenotyping platform and important early vigour traits such as shoot biomass, leaf area and plant height indicated that the derived plant parameters can be used to predict vigour traits in field pea seedlings. Plant growth analysis demonstrated that the "broken-stick" model fitted well with the growth pattern of all field pea genotypes and can be used to determine the linear growth phase. Further analysis suggested that the estimated plant parameters collected at the linear growth phase can effectively differentiate early vigour across field pea genotypes. High correlation between normalised difference vegetation indices captured from the field trial and estimated shoot biomass and top-view area confirmed the consistent performance of early vigour field pea genotypes under controlled and field environments. Overall, our results demonstrated that this robust screening tool is highly applicable and will enable breeding programs to rapidly identify early vigour traits and utilise germplasm to contribute to the genetic improvement of field peas.


Assuntos
Ambiente Controlado , Processamento de Imagem Assistida por Computador , Fenótipo , Pisum sativum/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Automação , Genótipo , Pisum sativum/genética , Plântula/genética
19.
J Am Acad Orthop Surg Glob Res Rev ; 2(7): e030, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30280142

RESUMO

BACKGROUND: The aim of this study was to determine the amount of radiation exposure from intraoperative imaging during two-level and four-level lumbar fusions. METHODS: Five imaging systems were studied: multidetector CT (MDCT) scanner (CT A); two mobile CT units (CT B and CT C); a C-arm (D); and fluoroscopy (E). Metal oxide semiconductor field effect transistor dosimeters measured doses at 25 organ locations using an anthropomorphic phantom. A fat-equivalent phantom was used to simulate an obese body mass index (BMI). RESULTS: The effective dose (ED) for C-arm D was estimated using commercial software. The ED for others was computed from the measured mean organ doses. EDs for a normal BMI patient, receiving a four-level fusion, are as follows: CT A (12.00 ± 0.30 mSv), CT B (5.90 ± 0.25 mSv), CT C (2.35 ± 0.44 mSv), C-arm D (0.44 mSv), and fluoroscopy E (0.30 ± 0.3 mSv). The rankings are consistent across all three BMI values except CT C and fluoroscopy E, which peaked in the overweight size because of system limitations. The other machines' ED trended with patient BMI. CONCLUSION: The dose reduction protocols were confirmed according to the manufacturer's specifications. The results of this study emphasize the need for the appropriate selection of the imaging system, especially because the type of device could have a substantial effect on patient radiation risk.

20.
ACS Appl Mater Interfaces ; 10(25): 21601-21611, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29856596

RESUMO

An ionic conducting membrane is an essential part in various electrochemical devices including ionic actuators. To miniaturize these devices, micropatterns of ionic conducting membrane are desired. Here, we present a novel type of ionogel that can be patterned using standard photolithography and soft imprinting lithography. The ionogel is prepared in situ by UV-initiated free-radical polymerization of thiol acrylate precursors in the presence of ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. The resultant ionogel is very flexible with a low Young's modulus (as low as 0.23 MPa) and shows a very high ionic conductivity (up to 2.4 × 10-3 S/cm with 75 wt % ionic liquid incorporated) and has a reactive surface due to the excess thiol groups. Micropatterns of ionogel are obtained by using the thiol acrylate ionogel solution as an ionic conducting photoresist with standard photolithography. Water, a solvent immiscible with ionic liquid, is used as the photoresist developer to avoid complete removal of ionic liquid from thin micropatterns of the ionogel. By taking advantage of the reactive surface of ionogels and the photopatternability, ionogels with complex three-dimensional microstructure are developed. The surface of the ionogels can also be easily patterned using UV-assisted soft imprinting lithography. This new type of ionogels may open up for building high-performance flexible electrochemical microdevices.

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