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1.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203414

RESUMO

In this study we define the optimal conditions for ultrasound-assisted extraction of bioactive polyphenols from S. raeseri aerial parts using response surface methodology. The influence of ethanol concentration (10-90%), extraction temperature (20-80 °C), extraction time (10-60 min), and solid-to-solvent ratio (1:10-1:50) on total phenolic content as well as on content of individual flavonoids, and hypolaetin and isoscutellarein derivatives was studied. For the experimental design, a central composite design was chosen. In the obtained extracts, the following ranges of targeted compounds were detected: total phenol from 19.32 to 47.23 mg GAE/g dw, HYP from 1.05 to 11.46 mg/g dw, ISC 1 from 0.68 to 10.68 mg/g dw, and ISC 2 from 0.74 to 15.56 mg/g dw. The optimal extraction conditions were set as: ethanol concentration of 65%, extraction time of 50 min, extraction temperature of 63 °C, and solid-to-solvent ratio of 1:40. Contents of TP, HYP, ISC 1, and ISC 2 in optimal extracts were 47.11 mg GAE/g dw, 11.73 mg/g dw, 9.54 mg/g dw, and 15.40 mg/g dw, respectively. Experimentally set values were in good agreement with those predicted by the response surface methodology model, indicating suitability of the used model, as well as the success of response surface methodology in optimizing the conditions of the extraction.


Assuntos
Flavonoides , Micro-Ondas , Fenóis , Sideritis/química , Sonicação , Flavonoides/química , Flavonoides/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação
2.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204905

RESUMO

Cyclodipeptides (CDPs) or 2,5-diketopiperazines (DKPs) can exert a variety of biological activities and display pronounced resistance against enzymatic hydrolysis as well as a propensity towards self-assembly into gels, relative to the linear-dipeptide counterparts. They have attracted great interest in a variety of fields spanning from functional materials to drug discovery. This concise review will analyze the latest advancements in their synthesis, self-assembly into gels, and their more innovative applications.


Assuntos
Dicetopiperazinas/síntese química , Dipeptídeos/química , Peptídeos Cíclicos/síntese química , Dicetopiperazinas/química , Géis/química , Química Verde , Micro-Ondas , Estrutura Molecular , Peptídeos Cíclicos/química
3.
An Acad Bras Cienc ; 93(2): e20190632, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259791

RESUMO

The present study consisted in optimizing the extractive method of polyphenols and total tannins of leaves of Syzygium cumini (L) Skeels assisted by microwaves to potentiate the antimicrobial activity of the dried extract of S. cumini against sensitive and resistant strains. A Box-Behnken design that consisted of 27 experimental runs coupled with a desirability function for multiple response optimization was employed to optimize the total polyphenols content and total tannins content. Antimicrobial sensitivity tests were evaluated by obtaining the minimum inhibitory concentration, minimum fungicidal concentration and minimum bactericidal concentration in 96-well petri dishes. The optimal extraction conditions were found to be 8 min of extraction, under 300 w of microwave power, using a 1:34 g/mL solid/solvent ratio and 38% of ethanol concentration as extraction solvent. The parameter with the greatest influence in the extraction was primarily the time, followed by the potency and proportion solid/solvent. This yielded a total polyphenol content of 87.37 ± 1.85 mg TAE g-1ext and a total tannin content of 79.68 ± 1.64 mg TAE g-1 ext. All tested microorganisms were sensitive to the extract, evidencing the effectiveness of the extraction method optimization.


Assuntos
Polifenóis , Syzygium , Antioxidantes , Micro-Ondas , Extratos Vegetais/farmacologia , Folhas de Planta , Projetos de Pesquisa , Taninos
4.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206102

RESUMO

Oral health problems may occur as a result of the ingestion of acid drinks. The objective of this in vitro study was to quantify and screen the concentration of potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), manganese (Mn), zinc (Zn), iron (Fe), copper (Cu), barium (Ba), lead (Pb), arsenic (As), cadmium (Cd), aluminum (Al), cobalt (Co), chromium (Cr), molybdenum (Mo), sodium (Na), nickel (Ni), selenium (Se), and vanadium (V) released from bovine incisors during an erosive challenge at different times of exposure when immersed in Coca-Cola™, orange juice, and grape juice. A total of 240 samples of bovine incisor teeth were used for the erosive challenge and allocated in groups. Digestion of drinks was performed using microwave-assisted digestion. The content in acidic drinks was monitored before and after the erosive challenge at exposure times of 1, 5, and 60 min using inductively coupled plasma optical emission spectrometry (ICP OES). The drinks' pH varied slightly during the erosive challenge but remained below the critical value of pH 5 to cause tooth demineralization. The concentrations of elements released from the bovine incisors during the in vitro erosive challenge depend on exposure times when immersed in acidic beverages. For some elements such as Ca, Mn, Zn, Fe, Cu, Ba, Pb, As, and Cd, quantified in acidic drinks, grape juice had greater erosive potential than Coca-Cola™ and orange juice. Quantification and monitoring of chemical elements in bovine teeth can be performed considering a longer erosive time and other types of acidic drinks. Further analysis using human teeth is still not available and must be conducted. The demineralization of teeth not only occurs in acidic beverages; physical and chemical factors play other roles and should be investigated.


Assuntos
Bebidas Gaseificadas/efeitos adversos , Sucos de Frutas e Vegetais/efeitos adversos , Minerais/análise , Desmineralização do Dente/metabolismo , Animais , Bovinos , Modelos Animais de Doenças , Concentração de Íons de Hidrogênio , Incisivo/química , Incisivo/efeitos dos fármacos , Micro-Ondas , Espectrofotometria Atômica , Desmineralização do Dente/induzido quimicamente
5.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205529

RESUMO

Polyscias fruticosa (L.) leaves contain significant bioactive compounds with high antioxidant activity such as chlorophylls, total polyphenols, etc. but these have still been underutilized. In this study, the kinetics of chlorophyll and antioxidant activity extraction from P. fruticosa leaves by microwave-assisted extraction (MAE) were investigated. Microwave power was 300, 450, or 600 (W); the ratio of material/solvent varied from 1:40 to 1:80 (g/mL). In this study, the second-order kinetic model successfully predicted the change of chlorophyll and antioxidant activity during MAE. The increase of microwave power or/and the solvent amount increased saturated extraction efficiency and the extraction rate constant. However, the saturated concentration of chlorophyll and antioxidant activity increased with the increment of microwave power and the decrease in solvent amount.


Assuntos
Antioxidantes/farmacologia , Araliaceae/química , Clorofila/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Cinética , Micro-Ondas , Extratos Vegetais/química , Polifenóis/química , Polifenóis/farmacologia , Solventes/química
6.
Environ Pollut ; 284: 117493, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34261214

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) in soil can be recalcitrant to solvent extraction after aging. We showed in this study that mixing a small amount of water in the extracting solvent during microwave-assisted extraction (MAE) can release recalcitrant PAHs, resulting in significant improvement in the analyzed concentrations. The improvement factor (F) for the total of 16 priority PAHs (∑PAH16) listed by the United States Environmental Protection Agency was 1.44-1.55 for field soils. By comparing the F values for different soil organic components, we demonstrated that the recalcitrant PAHs were primarily associated with biochar, humic acid (HA), and humin (HM), with the F values for ∑PAH16 of 1.94, 6.62, and 4.59, respectively. The results showed that the recalcitrant PAHs comprised a sequestered fraction and a desorption-limited fraction. NMR spectra showed that water worked alone at elevated temperature to promote hydrolysis of biochar and destroy the macromolecular structure, thus causing the release of the otherwise sequestered PAHs during MAE. The substantial reduction in F values for HA and HM after demineralization indicated sequestration of PAHs in organic-mineral complexes, which can be destroyed by hot water treatment. The release of the sequestered fraction was nonselective and independent of compound hydrophobicity. In comparison, the release of the desorption-limited fraction was positively affected by the hydrophobicity of PAHs and was facilitated by the presence of water in the extracting solvent. The results of this study provide important insights into the sequestration and release of recalcitrant PAHs in soil.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Micro-Ondas , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo , Poluentes do Solo/análise , Solventes , Água
7.
Sensors (Basel) ; 21(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34300364

RESUMO

Protective SiO2 coating deposited to iron microparticles is highly demanded both for the chemical and magnetic performance of the latter. Hydrolysis of tetraethoxysilane is the crucial method for SiO2 deposition from a solution. The capabilities of this technique have not been thoroughly studied yet. Here, two factors were tested to affect the chemical composition and the thickness of the SiO2 shell. It was found that an increase in the hydrolysis reaction time thickened the SiO2 shell from 100 to 200 nm. Moreover, a decrease in the acidity of the reaction mixture not only thickened the shell but also varied the chemical composition from SiO3.0 to SiO8.6. The thickness and composition of the dielectric layer were studied by scanning electron microscopy and energy-dispersive X-ray analysis. Microwave permeability and permittivity of the SiO2-coated iron particles mixed with a paraffin wax matrix were measured by the coaxial line technique. An increase in thickness of the silica layer decreased the real quasi-static permittivity. The changes observed were shown to agree with the Maxwell Garnett effective medium theory. The new method developed to fine-tune the chemical properties of the protective SiO2 shell may be helpful for new magnetic biosensor designs as it allows for biocompatibility adjustment.


Assuntos
Micro-Ondas , Dióxido de Silício , Ferro , Magnetismo
8.
Sensors (Basel) ; 21(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34300413

RESUMO

The shallow neural network (SNN) is a popular algorithm in atmospheric parameters retrieval from microwave remote sensing. However, the deep neural network (DNN) has a stronger nonlinear mapping capability compared to SNN and has great potential for applications in microwave remote sensing. The Microwave Humidity and Temperature Sounder (Beijing, China, MWHTS) onboard the Fengyun-3 (FY-3) satellite has the ability to independently retrieve atmospheric temperature and humidity profiles. A study on the application of DNN in retrieving atmospheric temperature and humidity profiles from MWHTS was carried out. Three retrieval schemes of atmospheric parameters in microwave remote sensing based on DNN were performed in the study of bias correction of MWHTS observation and the retrieval of the atmospheric temperature and humidity profiles using MWHTS observations. The experimental results show that, compared with SNN, DNN can obtain better bias-correction results when applied to MWHTS observation, and can obtain higher retrieval accuracy of temperature and humidity profiles in all three retrieval schemes. Meanwhile, DNN shows higher stability than SNN when applied to the retrieval of temperature and humidity profiles. The comparative study of DNN and SNN applied in different atmospheric parameter retrieval schemes shows that DNN has a more superior performance.


Assuntos
Micro-Ondas , Redes Neurais de Computação , China , Umidade , Temperatura
9.
Sensors (Basel) ; 21(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34300610

RESUMO

This work presents a microwave reflectometry-based system for monitoring large concrete structures (during the curing process and also while the structure is in use), through the combined use of punctual and diffused sensing elements. In particular, the adoption of punctual probes on a reference concrete specimen allows the development of an innovative and accurate calibration procedure, useful to obtain the value of the water content on a larger structure made of the same material. Additionally, a wire-like diffused sensing element can be permanently embedded in buildings and used to monitor the structure along the entire length of the sensing element. The adopted diffused sensing element can be used not only to detect dielectric variation during the curing process, but also throughout the service life of the structure. The combined use of punctual and diffused sensing elements represents an important innovation from a procedural point of view, able to provide detailed and quantitative information on the health status of the structure both during and after construction.


Assuntos
Micro-Ondas , Água , Calibragem , Difusão , Monitorização Fisiológica
10.
Sensors (Basel) ; 21(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34200011

RESUMO

The microwave ablation technique to destroy cancer tissues in liver is practiced clinically and is the subject of ongoing research, e.g., ablation monitoring. For studies, liver tissue from cattle or pigs is often used as a substitute material. In this work, sweet potato is presented as an alternative material for microwave ablation experiments in liver due to similar material properties. Sweet potatoes as a substitute for liver have the advantages of better handling, easy procurement and stable material properties over time for microwave ablation experiments. The dielectric constant and electrical conductivity of sweet potato are characterized for temperature variation with the help of high-temperature dielectric probe. Furthermore, a test setup is presented for microwave ablation experiments in which a bowtie slot antenna matched to sweet potato is placed on its surface to directly receive the microwave power from a self-developed microwave applicator inserted into a sweet potato 4 cm below the surface antenna. A high-power source was used to excite the microwave powers up to 80 W and a spectrum analyzer was used to measure the signal received by the surface antenna. The experiments were performed in an anechoic chamber for safety reasons. Power at 50 W and 80 W was stimulated for a maximum of 600 s at the 2.45 GHz ISM band in different sweet potato experiments. A correlation is found between the power received by the surface antenna and rise of temperature inside sweet potato; relative received power drops from 1 at 76 ∘C to 0.6 at 88 ∘C (max. temperature) represents a 40% relative change in a 50 W microwave ablation experiment. The received power envelope at the surface antenna is between 10 mW and 32 mW during 50 W microwave ablation. Other important results for 10 min, 80 W microwave ablation include: a maximum ablation zone short axis diameter of 4.5 cm and a maximum ablation temperature reached at 99 ∘C, 3 mm away from the applicator's slot. The results are compared with the state of the art in microwave ablation in animal liver. The dielectric constant and electrical conductivity evolution of sweet potato with rising temperature is comparable to animal liver in 50-60 ∘C range. The reflection loss of self-developed applicator in sweet potato is below 15 dB which is equal to reflection loss in liver experiments for 600 s. The temperature rise for the first 90 s in sweet potato is 76 ∘C as compared to 73 ∘C in liver with 50 W microwave ablation. Similarly, with 80-75 W microwave ablation, for the first 60 s, the temperature is 98 ∘C in sweet potato as compared to 100 ∘C in liver. The ablation zone short-axis diameter after 600 s is 3.3 cm for 50 W microwave ablation in sweet potato as compared to 3.5 cm for 30 W microwave ablation in liver. The reasons for difference in microwave ablation results in sweet potato and animal liver are discussed. This is the first study to directly receive a signal from microwave applicator during a microwave ablation process with the help of a surface antenna. The work can be extended to multiple array antennas for microwave ablation monitoring.


Assuntos
Técnicas de Ablação , Ipomoea batatas , Solanum tuberosum , Animais , Bovinos , Fígado/cirurgia , Micro-Ondas , Suínos
11.
Sensors (Basel) ; 21(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200601

RESUMO

The possibility of non-invasive determination of the depth of the location and temperature of a cancer tumor in the human body by multi-frequency three-dimensional (3D) radiothermography is considered. The models describing the receiving of the human body's own radiothermal field processes are presented. The analysis of the possibility of calculating the desired parameters based on the results of measuring antenna temperatures simultaneously in two different frequency ranges is performed. Methods of displaying on the monitor screen the three-dimensional temperature distribution of the subcutaneous layer of the human body, obtained as a result of data processing of a multi-frequency multichannel radiothermograph, are considered. The possibility of more accurate localization of hyperthermia focus caused by the presence of malignant tumors in the depth of the human body with multi-frequency volumetric radiothermography is shown. The results of the study of various methods of data interpolation for displaying the continuous intrinsic radiothermal field of the human body are presented. Examples of displaying the volumetric temperature distribution by the moving plane method based on digital models and the results of an experimental study of the thermal field of the human body and head are given.


Assuntos
Hipertermia Induzida , Micro-Ondas , Temperatura Alta , Humanos , Imageamento Tridimensional , Radiometria
12.
Talanta ; 233: 122613, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215096

RESUMO

One of the aims of this study was to improve the sample throughput of a microwave-assisted closed vessel digestion system by using small quartz vials in polytetrafluoroethylene (PTFE) vessels for the sample preparation of raw propolis samples in small amounts. The digested samples were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) analyzing 36 elements. Limit of detection was low enough to measure all the elements, with the exception of La, in all raw propolis samples. There were no cross-contamination between the quartz vials, therefore independent samples can be prepared in the same PTFE vessel. Accuracy of the method was checked by spike recoveries and by analyzing BCR 189 wholemeal flour and two plant samples from a collaborative study. The means of RSDs were 5.3%-14.4% in the case of measured elements. The sample throughput was increased by three times using quartz vials in PFTE vessels besides matching with the requirements of green chemistry. Another goal was the characterization of the element content and thereby geographical identification of Hungarian raw propolis. In total, 252 samples were analyzed and their statistical characteristics were described. We cannot find globally such results of propolis element content, which is representing one country and with such a number of elements and samples. All the elements have positive skew and positive kurtosis. Concentration range is above two orders of magnitude in the case of Ba, Zn, V, Cr, Ni, Cd and Eu elements. The decimal logarithm of element concentrations was used for geographical identification of raw propolis samples originating from seven regions of Hungary by linear discriminant analysis (LDA). Grouping of the samples of the Northern Great Plain was the most effective with 96.3% and 77.8% based on the original method and the cross validation, respectively. The same indicators for all the groups are 76.6% and 61.5%.


Assuntos
Própole , Oligoelementos , Hungria , Espectrometria de Massas , Micro-Ondas , Quartzo , Análise Espectral , Oligoelementos/análise
13.
Shokuhin Eiseigaku Zasshi ; 62(3): 100-104, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34219097

RESUMO

A microwave digestion method for the analysis of tin, arsenic and lead in soft drinks was studied and its performance was evaluated. The trueness, repeatability (RSD) and Intralaboratory reproducibility (RSD) of the method were estimated to be in the ranges of 93-100, 0.7-6.1 and 0.9-8.6%, respectively. In the preparation of the samples for tin analysis, the addition of sulfuric acid after microwave digestion improved the recovery rate and reproducibility. To verify the applicability of this method, recovery tests were conducted on five types of soft drinks, and the results were satisfactory. It was confirmed that this method is applicable to the digestion of a wide range of soft drinks and to the analysis of tin, arsenic, and lead, and that it reduces working time and makes the work easier compared to the conventional method.


Assuntos
Arsênio , Arsênio/análise , Bebidas Gaseificadas , Digestão , Micro-Ondas , Reprodutibilidade dos Testes , Estanho
14.
Mater Sci Eng C Mater Biol Appl ; 126: 112170, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082971

RESUMO

Manganese-doped mesoporous hydroxyapatite (MnHAp) nanorods, a bio-apatite were synthesized via pyridinium chloride mediated microwave approach using bio-waste Donax variabilis seashells to treat orthopedic infections. This is the first report on using pyridinium chloride mediated mesoporous MnHAp nanorods synthesis. Pure and Mn doped HAp samples were examined using Raman spectroscopy, X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) studies to confirm the prepared HAp nanorods. Furthermore, the fabrication of manganese-doped HAp was successful with the formation of a hexagonal crystal lattice without disturbing the HAp phase. It is because, at the time of synthesis, PO43- ions form an electrostatic interaction with the Mn ions. Furthermore, Mn-doped HAp samples showed a reduction in their sizes of 15, 10-15, 5-10 nm width, and 80-100, 10-15, 20-30 nm length with varied pore diameters and surface area. The pure HAp, MnHAp-1, MnHAp-2, and MnHAp-3 nanorods disclose the surface area of 39.4, 18.0, 49.2, and 80.4 m2 g-1, with a pore volume of 0.0102, 0.0047, 0.0143, and 0.0447 cm3 g-1, the corresponding pore diameter was estimated to be 6, 7, 6, and 4 nm, respectively. Moreover, antibacterial activity reveals effective bactericidal action against infections causing pathogens whereas cytotoxicity examination (MTT assay), and zebrafish results reveal their non-toxic behavior. Therefore, it is evident from the study, that rapid fabrication of mesoporous and diverse structured MnHAp nanorods could be convenient with pyridinium chloride enabled microwave-assisted method as a bactericidal biomaterial for implant applications.


Assuntos
Durapatita , Nanotubos , Exoesqueleto , Animais , Cloretos , Micro-Ondas , Difração de Raios X , Peixe-Zebra
15.
Medicina (Kaunas) ; 57(5)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064587

RESUMO

Osteoid osteomas are one of the most common bone tumors. Although benign in nature, they can cause significant pain and distress to the afflicted patient. The main goal of treatment is to relieve pain. Historically, these tumors were treated with nonsteroidal anti-inflammatory drugs (NSAIDs) or surgery. Percutaneous ablative techniques have since gained popularity because of their efficacy and low risk profiles. Radiofrequency ablation was the first of these technologies used in the treatment of these tumors. More recently, microwave ablation has gained popularity. However, the literature is sparse regarding the safety and efficacy of this treatment. Here, we discuss our experience with microwave ablation in the treatment of osteoid osteomas in two patients and review the current literature on this technique. Microwave ablation in the treatment of osteoid osteoma seems to be a safe and effective treatment for this tumor.


Assuntos
Neoplasias Ósseas , Ablação por Cateter , Osteoma Osteoide , Ablação por Radiofrequência , Neoplasias Ósseas/cirurgia , Humanos , Micro-Ondas/uso terapêutico , Osteoma Osteoide/diagnóstico por imagem , Osteoma Osteoide/cirurgia , Resultado do Tratamento
16.
Sensors (Basel) ; 21(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066299

RESUMO

A complex permittivity characterization method for liquid samples has been proposed. The measurement is carried out based on a self-designed microwave sensor with a split ring resonator (SRR), the unload resonant frequency of which is 5.05 GHz. The liquid samples in capillary are placed in the resonant zone of the fabricated senor for high sensitivity measurement. The frequency shift of 58.7 MHz is achieved when the capillary is filled with ethanol, corresponding a sensitivity of 97.46 MHz/µL. The complex permittivity of methanol, ethanol, isopropanol (IPA) and deionized water at the resonant frequency are measured and calibrated by the first order Debye model. Then, the complex permittivity of different concentrations of aqueous solutions of these materials are measured by using the calibrated sensor system. The results show that the proposed sensor has high sensitivity and accuracy in measuring the complex permittivity of liquid samples with volumes as small as 0.13 µL. It provides a useful reference for the complex permittivity characterization of small amount of liquid chemical samples. In addition, the characterization of an important biological sample (inositol) is carried out by using the proposed sensor.


Assuntos
Micro-Ondas , Água
17.
Sensors (Basel) ; 21(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069045

RESUMO

The investigation of the electromagnetic properties of biological particles in microfluidic platforms may enable microwave wireless monitoring and interaction with the functional activity of microorganisms. Of high relevance are the action and membrane potentials as they are some of the most important parameters of living cells. In particular, the complex mechanisms of a cell's action potential are comparable to the dynamics of bacterial membranes, and consequently focusing on the latter provides a simplified framework for advancing the current techniques and knowledge of general bacterial dynamics. In this work, we provide a theoretical analysis and experimental results on the microwave detection of microorganisms within a microfluidic-based platform for sensing the membrane potential of bacteria. The results further advance the state of microwave bacteria sensing and microfluidic control and their implications for measuring and interacting with cells and their membrane potentials, which is of great importance for developing new biotechnologically engineered systems and solutions.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Bactérias , Potenciais da Membrana , Micro-Ondas
18.
Magy Seb ; 74(2): 37-42, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34133320

RESUMO

Összefoglaló. Célkituzés: A már több mint egy évtizede alkalmazott lézeres aranyérmutét technikai tapasztalatai alapján kidolgozott mikrohullámú termo-koagulációs mutét bevezetésének korai eredményeinek bemutatása. Közleményünkben a lézeres és microwave elven muködo eszközökkel végzett aranyérmutéti eredményeinket mutatjuk be. Betegek és módszerek: A 26 lézerszállal és a 14 mikrohullámú merev antennával végzett mutét összehasonlítását végeztük el. Eredmények: Mindkét csoportban az átlagos panaszmentesség 2 hét alatt alakult ki, a két módszer között jelentos különbséget nem találtunk. Megbeszélés: Az új mutéti eljárásokat kereso világunkban az általunk most kipróbált lehetoség lehetové teszi a gyors és teljes gyógyulást adó kezelést. A termo elven muködo rendszerek kevesebb fizikai roncsolással érik el a kívánt hatást. A microwave technika a lézeres beavatkozások biztonsági eloírásainak szükségessége és körülményessége nélkül alkalmazható. SUMMARY: Abstract: In addition to the traditional surgical options for hemorrhoid disease, newer treatment methods are evolving along the principle of reducing the burden on patients and providing similar or better healing. Thermo-based systems achieve the desired effect with less physical destruction. In this paper, we discuss the results of hemorrhoid surgery performed with laser and microwave devices. PATIENTS AND METHODS: We compare the results of 26 operations done with laser fibers and 14 operations using microwave rigid antennas. RESULTS: In both groups, the average complaint-free period developed within 2 weeks, no significant difference was found between the two methods. DISCUSSION: As we are always looking for new methods and surgical solutions, an option we are testing now indicates that thermal treatment can provide a quick and complete cure without the need for complicated safety requirements of laser interventions.


Assuntos
Micro-Ondas , Humanos
19.
ACS Chem Neurosci ; 12(12): 2122-2132, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34085811

RESUMO

Fermented soybean lipids (FSE-C) is an extract enriched in active lipid classes. To explore whether FSE-C can alleviate cognitive damage triggered by the exposure to microwave radiation through regulating lipid metabolism, we employed lipidomic profiling based on a UPLC-MS to investigate differential lipid metabolites in the serum and hippocampus of rats. The results showed that orally administered FSE-C could protect from cognitive damage in microwave-induced rats. Serum lipidomics indicated that FSE-C effectively facilitated the recovery of 43 differential lipid metabolites including 6 phosphatidylcholines (PCs), 5 phosphatidylethanolamines (PEs), 1 phosphatidylinositol, 3 lysophosphatidylcholines (LPCs), 6 lysophosphatidylethanolamines (LPEs), and 22 triglycerides (TGs), which was consistent with the analysis of serum TG levels. Moreover, FSE-C positively coordinated hexacosanoic acid, 2 PCs, 4 sphingomyelins (SMs), and 11 TGs, through the hippocampal lipidomics. Collectively, these findings suggested that phospholipid and TG metabolisms were significantly modified in microwave-exposed rats. TGs may be regarded as potential biomarkers to further investigate and evaluate the roles and functions of FSE-C on the attenuation of cognitive damage induced by microwave radiation.


Assuntos
Alimentos e Bebidas Fermentados , Lipidômica , Animais , Cromatografia Líquida , Cognição , Hipocampo , Metabolismo dos Lipídeos , Micro-Ondas , Ratos , Soja , Espectrometria de Massas em Tandem
20.
Molecules ; 26(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068025

RESUMO

Consumers are becoming more mindful of their well-being. Increasing awareness of the many beneficial properties of peppermint essential oil (EO) has significantly increased product sales in recent years. Hydrodistillation (HD), a proven conventional method, and a possible alternative in the form of microwave-assisted hydrodistillation (MWHD) have been used to isolate peppermint EO. Standard Soxhlet and alternatively supercritical fluid (SFE), microwave-assisted, and ultrasound-assisted extraction separated the lipid extracts. The distillations employed various power settings, and the EO yield varied from 0.15 to 0.80%. The estimated environmental impact in terms of electricity consumption and CO2 emissions suggested that MWHD is an energy efficient way to reduce CO2 emissions. Different extraction methods and solvent properties affected the lipid extract yield, which ranged from 2.55 to 5.36%. According to the corresponding values of statistical parameters, empiric mathematical models were successfully applied to model the kinetics of MWHD and SFE processes.


Assuntos
Meio Ambiente , Lipídeos/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Óleos Vegetais/isolamento & purificação , Dióxido de Carbono/análise , Destilação , Eletricidade , Cinética , Micro-Ondas , Tamanho da Partícula , Pressão
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