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1.
Food Chem ; 334: 127613, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711281

RESUMO

The optimization of ultrasound-assisted alkaline extraction and enzymatic deamidation by protein-glutaminase (PG) on evening primrose seed cake (EPSC) protein and its effect on structure (amino acid composition, secondary structure and electrophoresis pattern) and techno-functional properties (water-holding and oil-binding capacities, solubility, emulsifying and foaming properties) of EPSC protein were evaluated. The optimum conditions of the both processes were measured using response surface methodology (RSM). The maximum yield (26.4%) and protein content (86.1%) were reached at the optimized extraction conditions. Optimal conditions of PG deamidation based on reaching a high degree of deamidation (DD) with a simultaneously low degree of hydrolysis (DH). Under these conditions, DD and DH were 39.40 and 2.11%, respectively. Ultrasound-assisted alkaline extraction and enzymatic deamidation by PG have great potential to produce edible EPSC protein with modified techno-functional characteristics that can be used for several aims in the food and pharmaceutical applications.


Assuntos
Fracionamento Químico/métodos , Oenothera biennis/química , Proteínas de Vegetais Comestíveis/química , Amidas/química , Aminoácidos/análise , Emulsificantes/química , Glutaminase/química , Hidrólise , Extratos Vegetais/química , Óleos Vegetais/química , Proteínas de Vegetais Comestíveis/isolamento & purificação , Estrutura Secundária de Proteína , Solubilidade , Ultrassom
2.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 38(10): 767-769, 2020 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-33142384

RESUMO

Objective: To set up a new method to determine the nickel of urine in urine using dispersive liquid-liquid microextraction (DLLME) coupled with graphite furnace atomic absorption spectrometry (GFAAS) . Methods: From September 2018 to September 2019, the methanol, pyrrolidine dithiocarbamate and ionic liquid 1-hexyl-3-methyl-imidazolium hexafluorophosphate were used as dispersive solvent, the chelating agent and extraction solvent for the preconcentration of nickel, respectively. After adding into buffer solution of pH 9, ultrasonic dissolving for 10 minutes, centrifugal separation and then discarding the supernatant, the precipitate was saved. Dissolving the precipitate by methanol, mixing thoroughly on a vortex mixer, the 15 µl of the mixed solution was used for determination by graphite furnace atomic absorption spectrometry. Results: The linear correlation coefficient of urine nickel concentration in the range of 2.0-10.0 µg/L, r=0.999, with the detection limitation of 0.43 µg/L. The recovery rate and the relative standard deviations were 95.6%-103.7% and 2.53%-4.82%, respectively. Conclusion: The method, which has low detection limit, high recovery rate and good precision, is suitable for the determination of nickel in urine for the occupational populations exposure to nickel and non-occupational exposure.


Assuntos
Grafite , Líquidos Iônicos , Limite de Detecção , Níquel , Espectrofotometria Atômica , Ultrassom
3.
Shanghai Kou Qiang Yi Xue ; 29(3): 321-324, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-33043353

RESUMO

PURPOSE: To evaluate the clinical effect of 65 µm glycine powder air-polishing (GPAP) by comparing with sodium hydrogen carbonate after ultrasonic scaling during subgingival polishing. METHODS: Thirty-three patients who were systematically healthy were involved in this study. After ultrasonic scaling,they were randomly assigned to the experimental group or the control group. Patients in the control group were treated with rubber cup + sodium hydrogen carbonate, while patients in the experimental group were treated only with 65 µm GPAP therapy. The clinical parameters including probing depth(PD), bleeding index(BI), plaque index(PI), staining index(SI) were recorded at baseline, 1week, 1 month, 3 months and 6 months after treatment. The results were analyzed by paired sample Wilcoxon signed-rank test with SPSS 23.0 software package. RESULTS: Both methods had good clinical effects. PD, BI, PI and SI of the two groups at 1 month, 3 months and 6 months after treatment were significantly better than those at baseline (P<0.01). SI of the experimental groups was significantly lower than that of the control group at 1 month, 3 months and 6 months after treatment(P<0.01). CONCLUSIONS: The results indicated that 65 µm GPAP may be as effective as sodium hydrogen carbonate after ultrasonic scaling in removal of dental plaque and stain. 65 µm GPAP had the advantage of reducing restaining.


Assuntos
Glicina , Ultrassom , Raspagem Dentária , Humanos , Índice Periodontal , Bolsa Periodontal
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3289-3292, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018707

RESUMO

Untethered, wireless peripheral nerve recording for prosthetic control requires multi-implant communications at high data rates. This work presents a multiple-access ultrasonic uplink data communication channel comprised of 4 free-floating implants and a single-element external transducer. Using code-division multiple access (CDMA), overall channel data rates of up to 784 kbps were measured, and a machine-learning assisted decoder improved BER by >100x. Compared with prior art, this work incorporates the largest number of implants at the highest data rate and spectral efficiency reported.


Assuntos
Algoritmos , Ultrassom , Aprendizado de Máquina , Próteses e Implantes , Transdutores
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4093-4096, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018898

RESUMO

In this work, we present a proof-of-concept hydrogel-based sensor system capable of wireless biochemical sensing through measuring backscattered ultrasound. The system consists of silica-nanoparticle embedded hydrogel deposited on a thin glass substrate, presenting two interfaces for backscattering (tissue/hydrogel and hydrogel/glass), which allows for system output to be invariant under the change in acoustic properties (e.g. attenuation, reflection) of the intervening biological tissue. We characterize the effect of silica nanoparticles (acoustic contrast agents) loading on the hydrogel's swelling ratio and its ultrasonic backscattering properties. We demonstrate a wireless pH measurement using dual modes of interrogations, reflection ratio and time delay. The ultrasonic hydrogel pH sensor is demonstrated with a sensing resolution of 0.2 pH level change with a wireless sensing distance around 10 cm.


Assuntos
Hidrogéis , Nanopartículas , Dióxido de Silício , Ultrassom
6.
Int J Nanomedicine ; 15: 8075-8095, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116519

RESUMO

Purpose: Sonodynamic therapy (SDT) is a new therapeutic modality for the noninvasive cancer treatment based on the association of ultrasound and sonosensitizer drugs. Topical SDT requires the development of delivery systems to properly transport the sonosensitizer, such as zinc phthalocyanine (ZnPc), to the skin. In addition, the delivery system itself can participate in sonodynamic events and influence the therapeutic response. This study aimed to develop ZnPc-loaded micelle to evaluate its potential as a topical delivery system and as a cavitational agent for low-frequency ultrasound (LFU) application with the dual purpose of promoting ZnPc skin penetration and generating reactive oxygen species (ROS) for SDT. Methods: ZnPc-loaded micelles were developed by the thin-film hydration method and optimized using the Quality by Design approach. Micelles' influence on LFU-induced cavitation activity was measured by potassium iodide dosimeter and aluminum foil pits experiments. In vitro skin penetration of ZnPc was assessed after pretreatment of the skin with LFU and simultaneous LFU treatment using ZnPc-loaded micelles as coupling media followed by 6 h of passive permeation of ZnPc-loaded micelles. The singlet oxygen generation by LFU irradiation of the micelles was evaluated using two different hydrophilic probes. The lipid peroxidation of the skin was estimated using the malondialdehyde assay after skin treatment with simultaneous LFU using ZnPc-loaded micelles. The viability of the B16F10 melanoma cell line was evaluated using resazurin after treatment with different concentrations of ZnPc-loaded micelles irradiated or not with LFU. Results: The micelles increased the solubility of ZnPc and augmented the LFU-induced cavitation activity in two times compared to water. After 6 h ZnPc-loaded micelles skin permeation, simultaneous LFU treatment increased the amount of ZnPc in the dermis by more than 40 times, when compared to non-LFU-mediated treatment, and by almost 5 times, when compared to LFU pretreatment protocol. The LFU irradiation of micelles induced the generation of singlet oxygen, and the lipoperoxidation of the skin treated with the simultaneous LFU was enhanced in three times in comparison to the non-LFU-treated skin. A significant reduction in cell viability following treatment with ZnPc-loaded micelles and LFU was observed compared to blank micelles and non-LFU-treated control groups. Conclusion: LFU-irradiated mice can be a potential approach to skin cancer treatment by combining the functions of increasing drug penetration and ROS generation required for SDT.


Assuntos
Indóis/farmacologia , Micelas , Compostos Organometálicos/farmacologia , Ultrassom , Alumínio/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma Experimental/patologia , Fosfatidiletanolaminas/química , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis/química , Iodeto de Potássio/química , Oxigênio Singlete/química , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Suínos
7.
Zhonghua Yan Ke Za Zhi ; 56(9): 676-680, 2020 Sep 11.
Artigo em Chinês | MEDLINE | ID: mdl-32907300

RESUMO

Objective: To explore the role of the scoring and strain ratio methods of ultrasonic elastography in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Methods: A cross-sectional study. Twenty-five patients (25 eyes) with choroidal melanoma treated in the Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University from July to October 2016 were included in this study. There were 13 males and 12 females, with an average age of (48±12) years old. Twenty-five patients (25 eyes) with choroidal hemangioma treated in the same period were selected for differential diagnosis, including 12 males and 13 females, with an average age of (37±13) years. The lesions were examined by ultrasound elastography and scored, and the strain ratio of the tumor to the orbital tissue was measured. Two independent sample t test was used to compare the difference in the elasticity score and strain ratio between choroidal melanoma and choroidal hemangioma. The sensitivity, specificity and area under the receiver operating characteristic (ROC) curve were calculated to analyze the value of the two methods in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Results: The elastography score of choroidal melanoma was (3.48±0.77) points, including 2 points in 3 cases, 3 points in 8 cases, 4 points in 13 cases, and 5 points in 1 case. The elastography score of hemangioma was (2.28±0.46) points, including 2 points in 18 cases and 3 points in 7 cases. The difference in the elasticity score between patients with the two kinds of tumors was statistically significant (t=6.694, P<0.01). The strain ratio was 42.97±15.83 and 12.21±9.24 in the patients with choroidal melanoma and choroidal hemangioma, respectively, and the difference was statistically significant (t=8.392, P<0.01). Using 3 points as the diagnostic critical point of the elastography score, the sensitivity was 88.0%, the specificity was 72.0%, and the area under the ROC curve was 0.80 (95% cofidence interval: 0.663 to 0.900, P<0.01). Using 21.67 as the diagnostic critical point of the strain ratio, the sensitivity was 92.0%, the specificity was 92.0%, and the area under the ROC curve was 0.92 (95% cofidence interval: 0.808 to 0.978, P<0.01). Conclusions: Ultrasound elastography plays a role in the differential diagnosis of choroidal melanoma and choroidal hemangioma. The differential diagnostic value of the strain ratio method is higher than the scoring method. (Chin J Ophthalmol, 2020, 56: 676-680).


Assuntos
Técnicas de Imagem por Elasticidade , Hemangioma , Melanoma/diagnóstico por imagem , Adulto , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Ultrassom , Adulto Jovem
8.
Niger J Clin Pract ; 23(9): 1237-1242, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32913162

RESUMO

Aims: We evaluated and compared EndoActivator, CanalBrush, and passive ultrasonic irrigation (PUI) in the removal of calcium hydroxide and calcium hydroxide with iodoform and p-chlorophenol paste (Calcipast Forte) from artificial standardized grooves in the apical third of root canals. Materials and Methods: A total of 34 mandibular premolars were prepared and then split longitudinally. A standardized groove was prepared in the apical part of both segments. The grooves were filled with either calcium hydroxide or Calcipast Forte, and the segments were reassembled. CanalBrush, EndoActivator, or PUI were used. The amount of remaining medicament was evaluated using a four-grade scoring system. Results: None of the irrigation methods could completely remove the pastes from the grooves. More Calcipast Forte paste was detected compared with calcium hydroxide (P < 0.01). PUI was the least effective method in removing Calcipast Forte. Conclusions: It was more difficult to remove Calcipast Forte than a water-based calcium hydroxide paste.


Assuntos
Hidróxido de Cálcio/química , Clorofenóis , Cavidade Pulpar/patologia , Hidrocarbonetos Iodados , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/administração & dosagem , Terapia por Ultrassom/métodos , Humanos , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Irrigação Terapêutica/métodos , Terapia por Ultrassom/instrumentação , Ultrassom , Água
9.
PLoS One ; 15(9): e0239593, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970754

RESUMO

The method for increasing the separation efficiency of particles smaller than 2.5 micrometers by combined ultrasonic agglomeration and swirling flow technique is proposed in the article. The swirling flow creates areas with an increased concentration of particles on the outer radius of the vortex. The ultrasonic exposure on these areas leads to more efficient agglomeration and the formation of agglomerates of many times larger than the original particles. The resulting agglomerates are easily separated from the gas flow. The design of the agglomerator was developed. The vortex velocity is determined, at which ultrasonic exposure on the swirling flow increases the average particle size d32 = 2.5 micrometer to 4.5 times. The ultrasonic exposure on a rectilinear flow can increase the particle size no more than 1.6 times for comparison. The proposed method is compared with inertial gas clearing in a cyclone. It was found that the proposed combined method allows increasing the cleaning efficiency from 46% to 85% at ultrasonic exposure on the swirling flow in the agglomerator and cyclone.


Assuntos
Hidrodinâmica , Nanopartículas/química , Ultrassom/métodos , Aerossóis/metabolismo , Separação Celular/métodos , Tamanho da Partícula , Fenômenos Físicos
10.
J Oral Sci ; 62(4): 415-419, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32879157

RESUMO

This study sought to evaluate biofilm elimination using the HBW Ultrasonic Ring based on continuous ultrasonic irrigation. Forty-five premolars and molars with complex curvatures were included. An Enterococcus faecalis biofilm was established for 30 days on the extracted teeth. The teeth were then stratified into three experimental groups for instrumentation and irrigation (i.e. HBW Ultrasonic Ring, conventional irrigation, and passive ultrasonic irrigation). Pre- and post-instrumentation samples were collected, and reductions of bacterial load were evaluated by McFarland's scale, counting of colony-forming units, and scanning electronic microscopy. The HBW Ultrasonic Ring promoted a higher reduction in bacterial load relative to conventional irrigation (P < 0.05) and a similar reduction compared with passive ultrasonic irrigation (P > 0.05). These results suggest the HBW Ultrasonic Ring is a promising alternative modality for simultaneous instrumentation and irrigation during root canal treatment, achieving an appropriate level of bacterial reduction and allowing the passage of the irrigating solution throughout the entire working length.


Assuntos
Enterococcus faecalis , Irrigantes do Canal Radicular , Biofilmes , Cavidade Pulpar , Preparo de Canal Radicular , Hipoclorito de Sódio , Irrigação Terapêutica , Ultrassom
11.
J Environ Manage ; 276: 111311, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32871465

RESUMO

Environment-friendly disposal of coal fly ash (CFA) is essential for sustainable development and cleaner production of electricity in thermal power plants. Although CFA has been employed for soil amelioration, direct application of CFA to soil may pose risks such as heavy metal contamination. This study investigated recycling of CFA through a novel method, which employs the ultrasonic treatment of CFA before its application. Physico-chemical properties of refuse dump soil and CFA were analysed. Subsequently, the effect of ultrasonic treatment on the physico-chemical properties of CFA was investigated. Different ultrasonic parameters (ultrasonic frequency, time interval, and temperature) were studied using response surface methodology. Finally, plant growth experiments were conducted to verify the feasibility of using ultrasonically treated CFA (UTCFA) for soil amelioration. The results show that untreated CFA cannot be used for soil amelioration due to its unsuitable high pH (10.20) and threatening concentrations of trace elements (6.80 mg/kg for Cadmium and 109.75 mg/kg for Arsenic). Ultrasonic treatment increases the soil amelioration properties of CFA by decreasing pH (to 8.50-9.20), decreasing concentrations of Cadmium and Arsenic (satisfying GB 15618-2018), and improving the water-holding capacity of CFA (reducing water loss). Plant indicators confirm the feasibility of using UTCFA for soil amelioration and suggest that the optimum UTCFA proportion is 20%. This study is a benchmark for the utilisation of ultrasonic treatment to improve the soil amelioration properties of CFA.


Assuntos
Cinza de Carvão , Metais Pesados , Carvão Mineral/análise , Cinza de Carvão/análise , Metais Pesados/análise , Solo , Ultrassom
12.
Artigo em Inglês | MEDLINE | ID: mdl-32882988

RESUMO

BACKGROUND: In recent years, ultrasonic vocalizations (USV) in pups has become established as a good tool for evaluating behaviors related to communication deficits and emotional states observed in autism spectrum disorder (ASD). Prenatal valproic acid (VPA) exposure leads to impairments and social behavior deficits associated with autism, with the effects of VPA being considered as a reliable animal model of ASD. Some studies also suggest that prenatal exposure to chlorpyrifos (CPF) could enhance autistic-like behaviors. METHODS: In order to explore these similarities, in the present study we tested whether prenatal exposure to CPF at GD12.5-14.5 produces effects that are comparable to those produced by prenatal VPA exposure at GD12.5 in infant Wistar rats. Using Deep Squeek software, we evaluated total number of USVs, latency to the first call, mean call duration, principal frequency peak, high frequency peak, and type of calls. RESULTS: Consistent with our hypothesis, we found that exposure to both CPF and VPA leads to a significantly smaller number of calls along with a longer latency to produce the first call. No significant effects were found for the remaining dependent variables. CONCLUSIONS: These results suggest that prenatal exposure to CPF could produce certain behaviors that are reminiscent of those observed in ASD patients.


Assuntos
Transtorno do Espectro Autista , Clorpirifos , Inibidores Enzimáticos , Efeitos Tardios da Exposição Pré-Natal , Ácido Valproico , Vocalização Animal , Animais , Transtorno do Espectro Autista/induzido quimicamente , Clorpirifos/toxicidade , Modelos Animais de Doenças , Inibidores Enzimáticos/toxicidade , Feminino , Humanos , Recém-Nascido , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Ratos , Ratos Wistar , Ultrassom , Ácido Valproico/toxicidade , Vocalização Animal/efeitos dos fármacos
13.
J Int Acad Periodontol ; 22(4): 187-204, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980832

RESUMO

AIMS: To systemically review the literature on the effect of hand and sonic/ultrasonic instruments used for the non-surgical treatment of periodontitis. MATERIALS AND METHODS: Five databases were searched for randomized clinical trials that compared the results of periodontal treatment using hand and sonic/ultrasonic for nonsurgical periodontal treatment. Four meta-analyses were performed, using the calculated mean differences (MD) between baseline and 3-months or 6-months after periodontal treatment for clinical attachment level (CAL), and probing pocket depth (PPD). RESULTS: Eighteen studies were included. All included studies showed significant improvement, in at least one periodontal parameter, in both tested periodontal therapies. The sonic/ultrasonic instruments spend significantly less time in comparison to manual instrumentation. At both 3- and 6-months after periodontal therapy, no statistically significant differences were detected for CAL gain between therapies (MD; 95%CI: 0.05; -0.21-0.30 and -0.23; -0.59-0.12). Similarly, no statistically significant differences were detected for PPD reduction between therapies at 3-months of follow-up (MD; 95%CI: -0.03; -0.34-0.28). After 6-months, the PPD reduction was 0.21 (95%CI: -0.43-0.00, p=0.05). CONCLUSION: Similar results may be expected for the periodontal treatment performed with hand and sonic/ultrasonic instruments. However, further studies with lower risk of bias are warranted.


Assuntos
Raspagem Dentária , Periodontite , Mãos , Humanos , Aplainamento Radicular , Ultrassom
14.
Medicine (Baltimore) ; 99(34): e21937, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846863

RESUMO

RATIONALE: Microspherophakia is characterized by a small, spherical crystalline lens with increased sagittal diameter. Because of the uncertainty about the outcome, as well as the complexity of the operation and development of complications, the management and timing of surgical intervention for microspherophakia are still debated. Lens extraction is effective for avoiding the risk of pupillary blockage, but the outcome after operation is controversial. The iTrace (Tracey, USA) report shows the influence of low-order aberrations (LOA) and high-order aberrations (HOA), which may be valuable in predicting postoperative outcome. Our report concerns a child with microspherophakia who underwent lens extraction via the analysis of visual quality by iTrace. PATIENT CONCERNS: Our report is on the case of a 7-year-old girl whose parents observed she had to bring her papers and books extremely close to her face to read. On examination, the girl was bilaterally diagnosed microspherophakia with a small tremble lens. The objective refraction was -15.0 diopter of spherical power (DS)/-1.00 diopter of cylindrical power (DC) × 180 right eye (OD) and -12.5 DS/-1.50 DC × 20 left eye (OS). The HOA of OD and OS were high up to 0.926 and 0.659, respectively by iTrace. The visual quality remained terrible after correcting LOA (high myopia and astigmatism). According to iTrace report, the patient would get a good visual quality by extracting the clear lens with HOA from cornea after correcting LOA. The girl's parent opted for surgery on the left eye. DIAGNOSIS: Due to the patient's symptoms, examination results, she was diagnosed with microspherophakia. INTERVENTIONS: The patient underwent clear lens extraction by ultrasonic phacoemulsification and intraocular lens implantation. OUTCOMES: The first day after operation, total HOA was decreased to 0.077. Total LOA was 0.713. Corrected distance visual acuity (CDVA) is 20/20. One week after surgery, HOA was 0.110 and LOA was 0.328. CDVA was 20/25. CDVA was still 20/25 one month after surgery. The total HOA was 0.110 and the LOA was 0.334 by iTrace. LESSONS: ITrace not only plays an important role in analyzing potential reasons of undesirable preoperative visual quality but also can predict postoperative outcomes. All these functions are helpful for determining surgical intervention of microspherophakia cases.


Assuntos
Aberrometria/instrumentação , Doenças da Córnea/cirurgia , Ectopia do Cristalino/cirurgia , Glaucoma/cirurgia , Iris/anormalidades , Implante de Lente Intraocular/métodos , Facoemulsificação/instrumentação , Ultrassom/métodos , Astigmatismo/cirurgia , Criança , Doenças da Córnea/diagnóstico , Topografia da Córnea/instrumentação , Ectopia do Cristalino/diagnóstico , Feminino , Glaucoma/diagnóstico , Humanos , Iris/cirurgia , Miopia/cirurgia , Resultado do Tratamento , Acuidade Visual
15.
Neuron ; 107(3): 399-401, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758444

RESUMO

A circuit understanding of how perception links to response requires integrating neural connectivity, activity, and behavior. In this issue of Neuron, Tasaka et al. (2020) target neurons activated by ultrasonic pup vocalizations and discover a functional synaptic network embedded through acoustically selective TeA neurons that help link the calls to a discriminative maternal behavioral response.


Assuntos
Córtex Auditivo , Animais , Humanos , Lactente , Camundongos , Neurônios , Ultrassom
16.
J Chromatogr A ; 1627: 461380, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823093

RESUMO

Microwave-ultrasonic assisted aqueous enzymatic extraction (MUAAEE) was applied to extract tiger nut oil (TNO). The conditions of MUAAEE were optimized by Plackett-Burman design followed Box-Behnken design. An oil recovery of 85.23% was achieved under optimum conditions of a 2% concentration of mixed enzyme including cellulase, pectinase and hemicellulase (1/1/1, w/w/w), particle size <600 µm, microwave power 300 W, ultrasonic power 460 W, radiation temperature 40 °C, time 30 min, enzymolysis temperature 45 °C, pH 4.9, liquid-to-solid ratio 10 mL/g and time 180 min. Oil by MUAAEE revealed the similar fatty acid compositions, triglyceride compositions, thermal behaviour and flavour compared with oil by Soxhlet extraction (SE), while the oil quality of MUAAEE is superior to that of SE. Scanning electron microscopy revealed that structural disruption of tiger nut caused by MUAAEE facilitated the oil extraction. Results suggest that MUAAEE could be an efficient and environment-friendly method for extraction of TNO.


Assuntos
Cyperus/química , Enzimas/metabolismo , Micro-Ondas , Nozes/química , Óleos Vegetais/química , Ultrassom , Varredura Diferencial de Calorimetria , Celulase/metabolismo , Análise Discriminante , Ácidos Graxos/química , Glicosídeo Hidrolases/metabolismo , Poligalacturonase/metabolismo , Análise de Componente Principal , Reprodutibilidade dos Testes , Temperatura , Triglicerídeos/análise , Água/química
17.
Electromagn Biol Med ; 39(4): 340-346, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32772742

RESUMO

All therapeutic methods dealing with coronavirus (past and present) are based on chemicals. We test for it (positive or negative) chemically and hope to cure it with a future vaccine (some complicated chemical preparation). If and when the virus mutates, another set of chemical protocols for its testing and a hunt for new chemicals as a vaccine shall begin again and again. But the history of modern (western) medicine tells us that our biotechnology is not so limited. Copious scientific evidence for sonic and low energy electromagnetic signals produced by all biological elements (DNA, cells, bacteria, parasites, virus) exists; in turn, the biological elements are affected by these non-chemical signals as well. A careful analysis and a catalogue of the spectrum of these non-chemical signals are proposed here as a unique biophysical signature.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Modelos Biológicos , Pneumonia Viral/virologia , Ondas de Rádio , Fenômenos Fisiológicos Bacterianos , Fenômenos Biofísicos , DNA/química , Fenômenos Eletromagnéticos , Humanos , Interações Microbianas/fisiologia , Nanofios/química , Pandemias , Transdução de Sinais/fisiologia , Ultrassom , Água/química
18.
J Hist Dent ; 68(2): 71-86, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32852269

RESUMO

For decades the dismantling of previous dental work to correct inferior root canal procedures or to address recurrent dental caries has provided a significant amount of work for the restorative dentist. When coupled with teeth that have been root treated and also have an intraradicular post or dowel, the clinician was often presented with the challenge of post removal, without fracturing the root, and revision (retreatment) of the root canal procedures. While today's contemporary dentistry has the wherewithal to use ultrasonic devices to loosen and remove the post, this was not always the case historically, and creativity in this process was the hallmark of many of our predecessors.


Assuntos
Técnica para Retentor Intrarradicular , Cárie Dentária , Humanos , Retratamento , Tratamento do Canal Radicular , Ultrassom
19.
J Chromatogr A ; 1625: 461307, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709350

RESUMO

In this study, the ultrasonic-assisted dispersive solid phase extraction (UA-d-SPE) method coupled to gas chromatography-mass spectrometry (GC-MS) was applied for the analysis of phthalate esters in drinking water and distilled herbal beverages (Rosa, Mentha, Cichorium). A new nanocomposite based on layered double hydroxide supported on graphene oxide was synthesized and modified by sulfonated polyaniline via a simple one-pot in-situ polymerization method. The structure and morphology of the nanocomposite was confirmed by means of complementary techniques: Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and transmission electron microscopy. The effects of key parameters including adsorbent mass, type and amount of back extraction solvent, extraction and desorption time, pH of the solution and ionic strength were optimized and good precision and sensitivity were achieved. Under the optimum conditions, the limits of detection were between 0.06-0.3 ng mL-1 in aqueous solutions. The hybrid nanomaterial exhibited good adsorption ability toward phthalates in drinking water and distilled herbal beverages. The relative standard deviations (RSD%) for beverage samples varied from 0.1% to 9.9% (n = 3). The relative recoveries varied from 54.5% to 112.6%.


Assuntos
Compostos de Anilina/química , Bebidas/análise , Grafite/química , Hidróxidos/química , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida/métodos , Ácidos Sulfônicos/química , Ultrassom/métodos , Adsorção , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Nanocompostos/química , Concentração Osmolar , Ácidos Ftálicos/análise , Preparações de Plantas/química , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Difração de Raios X
20.
Chemosphere ; 255: 127034, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679634

RESUMO

Due to the increasing presence of plastic and plastic associated contaminants in the aquatic environments, the monitoring of this contamination in fish products and the understanding of possible human health implications is considered urgent. However, data are still relatively scarce, mostly due to the methodological challenges in the chemical analysis: these contaminants are ubiquitous and procedural contamination from the laboratory is frequent. In this work, we compared solid-phase microextraction (SPME) to ultrasonic assisted solvent extraction (UASE) as sample preparation methods for the liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) determination of phthalates in fish fillets. UASE was carried out with an acetone-hexane (1:1) solution and according to a reference procedure aimed to obtain the exhaustive extraction of the target analytes. SPME was carried out by applying C18 fibers in direct immersion mode and by using water/methanol 20:80 mixture to desorb the aliquot required for the analysis. Overall, SPME displayed an improved control of the background contamination and enabled lower LOQs. Precision, calculated as relative standard deviation (RSD) on replicates of a reference sample, was below 24% for both the method. Analysis of real samples purchased from Italian supermarkets showed that SPME might be an efficient tool for estimating the risk associated with fish consumption.


Assuntos
Peixes/metabolismo , Ácidos Ftálicos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Cromatografia Líquida/métodos , Microextração em Fase Sólida/métodos , Solventes/química , Espectrometria de Massas em Tandem/métodos , Ultrassom
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