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1.
Foods ; 12(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685096

RESUMO

Samara oil (Elaeagnus mollis Diels kernel oil) exhibits diverse healthy functions; however, the effect of extraction on its quality is still unclear. The present study was undertaken to evaluate the effect of extraction methods (solvent extraction: ethyl acetate, acetone, n-hexane, and petroleum ether; mechanical extraction: hot-pressing and cold-pressing) on the color, acid value, peroxide value, fatty acid composition, bioactive compounds, antioxidant activities, and oxidative stability index of samara oil obtained from Elaeagnus mollis Diels kernels. The results indicated that extraction methods affected the physicochemical properties, chemical composition, and antioxidant activities of samara oil except for fatty acid composition and γ-tocopherol. The highest values of bioactive compounds including polyphenols (140.27 mg gallic acid equivalent (GAE)/kg) and carotenoids (42.95 mg/kg) were found in samara oil extracted with acetone. The values of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays, as well as oxidative stability index (OSI), were the highest in this oil. Correlation analysis results demonstrated that DPPH, ABTS, and OSI of samara oil were positively correlated with polyphenols and carotenoids. After evaluation, acetone could be used to extract samara oil. The study provides new information on the samara oil process.

2.
Heliyon ; 8(11): e11851, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36458307

RESUMO

The abundance of pineapple waste generated in Malaysia has becomes a serious issue as it puts our environment in grave danger. The presence of chlorophyll in pineapple waste has attracted many researchers to produce a natural dye from chlorophyll as a sensitizer for solar cells. Natural dyes can be considered a promising substitute for synthetic dyes as they are more environmentally friendly and cost less when compared to the synthetic dyes that are currently available on the market. This research aims to optimize the conditions of chlorophyll extraction from pineapple leaves using a mechanical extraction method. A response surface methodology was used to design an experimental design table using a central composite design based on two significant factors. The extraction cycle and the storage time varied between 1 and 5 cycles and 7 and 9 h, respectively, were studied. From the study, the maximum concentration of total chlorophyll (TC) was 693.292 mg/L. The optimum conditions for extraction cycle and storage time were at 3 cycles and 8 h, respectively. Among those two factors, it has been discovered that the storage time has a smaller p-value (p = 0.1106) than the extraction cycle, indicating that this factor was the critical factor affecting the TC concentration. The value of R2 for the analysis was 0.8673, making the analysis a well-fitted model. Thus, it has been established that the models are suitable for optimizing the extraction conditions in order to maximize the concentration of TC using the mechanical method.

3.
Methods Enzymol ; 670: 459-497, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35871844

RESUMO

Carotenoid pigments serve many endogenous functions in organisms, but some of the more fascinating are the external displays of carotenoids in the colorful red, orange and yellow plumages of birds. Since Darwin, biologists have been curious about the selective advantages (e.g., mate attraction) of having such ornate features, and, more recently, advances in biochemical methods have permitted researchers to explore the composition and characteristics of carotenoid pigments in feathers. Here we review contemporary methods for extracting and analyzing carotenoids in bird feathers, with special attention to the difficulties of removal from the feather keratin matrix, the possibility of feather carotenoid esterification and the strengths and challenges of different analytical methods like high-performance liquid chromatography and Raman spectroscopy. We also add an experimental test of current common extraction methods (e.g., mechanical, thermochemical) and find significant differences in the recovery of specific classes of carotenoids, suggesting that no single approach is best for all pigment or feather types.


Assuntos
Carotenoides , Plumas , Animais , Aves , Cromatografia Líquida de Alta Pressão , Plumas/química , Pigmentação
4.
Skin Appendage Disord ; 8(3): 256-260, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35707295

RESUMO

Introduction: A fragment of hair penetrating the skin has been referred to as cutaneous pili migrans in the literature. The condition is regarded rare and the cause unknown. Case Presentation: A 55-year-old female experienced painful sensations of the sole. Dermoscopy revealed hair fragments penetrating the skin, and histopathology a hair shaft embedded in the stratum corneum. The hairs were mechanically extracted with immediate relief from the pain. Discussion and Conclusion: Hair splinters of the sole may be a cause of foot pain related to the skin. The hair splinter is yet another form of hair that has embedded itself in the skin. Patients may believe the hair is growing out of the feet, while the soles are among the specialized skin regions that are hairless. The origin of the hair is exogenous and related to an exposure to freshly cut human or animal hair. Cutaneous embedded hairs can be classified based on the clinical presentation, the location, and association with hair follicles into hair splinters, interdigital pilonidal sinus, migrating hair, or ingrown hair. The condition is an important cause of foot pain and should be considered on clinical examination of the skin of the soles.

5.
Carbohydr Polym ; 223: 115114, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426972

RESUMO

A simple process for extracting cellulose nanocrystals (CNCs) is proposed that only uses high-pressure homogenization (HPH) controlling a process temperature. The proposed process was assessed and compared with normal production through acidic hydrolysis. Temperature-controlled HPH produced CNCs with high crystallinity, which linearly increased with increasing process temperature over 20 passes. The CNCs had uniform widths and lengths in the ranges of 4-14 nm and 60-320 nm, respectively. Undesirable chemical reaction can be avoided with the proposed process because no chemical was used to promote the CNC extraction. This method is an efficient and sustainable green approach to CNC production.


Assuntos
Celulose/química , Celulose/isolamento & purificação , Nanopartículas/química , Hidrólise , Tamanho da Partícula , Pressão , Propriedades de Superfície , Temperatura
6.
Materials (Basel) ; 10(11)2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29120398

RESUMO

Developing an eco-friendly industry based on green materials, sustainable technologies, and optimum processes with low environmental impact is a general societal goal, but this remains a considerable challenge to achieve. Despite the large number of research on green structural composites, limited investigation into the most appropriate manufacturing methodology to develop a structural material at industrial level has taken place. Laboratory panels have been manufactured with different natural fibers but the methodologies and values obtained could not be extrapolated at industrial level. Bamboo industry panels have increased in the secondary structural sector such as building application, flooring and sport device, because it is one of the cheapest raw materials. At industrial level, the panels are manufactured with only the inner and intermediate region of the bamboo culm. However, it has been found that the mechanical properties of the external shells of bamboo culm are much better than the average cross-sectional properties. Thin strips of bamboo (1.5 mm thick and 1500 mm long) were machined and arranged with the desired lay-up and shape to obtain laminates with specific properties better than those of conventional E-Glass/Epoxy laminates in terms of both strength and stiffness. The strips of bamboo were bonded together by a natural thermoplastic polylactic acid (PLA) matrix to meet biodegradability requirements. The innovative mechanical extraction process developed in this study can extract natural strip reinforcements with high performance, low cost, and high rate, with no negative environmental impact, as no chemical treatments are used. The process can be performed at the industrial level. Furthermore, in order to validate the structural applications of the composite, the mechanical properties were analyzed under ageing conditions. This material could satisfy the requirements for adequate mechanical properties and life cycle costs at industrial sectors such as energy or automotive.

7.
Malar J ; 16(1): 14, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28049476

RESUMO

BACKGROUND: Tens of millions of people live in mosquito-infested regions and controlling mosquito-borne diseases is one of the major interventions aimed at alleviating poverty worldwide. The use of insecticide-treated textiles is one of the most widespread control measures. This includes bed nets, battle clothing or, more generally, textiles use for clothing. These textiles are generally treated with permethrin as active ingredient, which is dosed after extraction of the active molecule present throughout the fabric (measured in mg permethrin/g of fabric) and does not take the effective concentration on the textile surfaces into account. The objective of this study was to propose an improved dosage method that enables measurement of the bioavailable or effective part of active ingredients on the surface of textile treated with insecticides. METHODS: The proposed method relies on mechanical extraction of active molecules on the surface of the textile in direct contact with either the skin or with the targeted arthropod. RESULTS: The results showed that the amount of permethrin measured using the current method is about 200 times higher than the effective surface concentration of the insecticide. In addition, the type of weave or knit influences the effective concentrations of permethrin on the surface of the textile. With the current dosage method, the variation in the concentration of permethrin depending on the type of weave is maximum 8%, whereas with the proposed method, it varies by about 50%. These results were confirmed by bioassays, in which the type of weave significantly affected (p < 10-3) the 100% knockdown time of Anopheles gambiae. CONCLUSIONS: The bioefficacy of insecticide treatments of fabrics is directly correlated with the effective concentration of insecticide on the textile surface, which can be quantified using the method proposed. This improved method could be used to redefine the limits of actual concentrations of active substance after assessment of the bioefficacy of the treatment and the risk to human health. Further, it enables assessments of the kinetics of insecticide migration in the case of long-lasting insecticide treatment.


Assuntos
Técnicas de Química Analítica/métodos , Inseticidas/análise , Propriedades de Superfície , Têxteis , Animais , Anopheles/efeitos dos fármacos , Bioensaio
8.
ACS Appl Mater Interfaces ; 8(1): 215-24, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26701744

RESUMO

More than 30 years separate the two largest oil spills in North American history (the Ixtoc I and Macondo well blowouts), yet the responses to both disasters were nearly identical in spite of advanced material innovation during the same time period. Novel, mechanically durable sorbents could enable (a) sorbent use in the open ocean, (b) automated deployment to minimize workforce exposure to toxic chemicals, and (c) mechanical recovery of spilled oils. Here, we explore the use of two mechanically durable, low-density (0.1-0.2 g cm(-3)), highly porous (85-99% porosity), hydrophobic (water contact angles >120°), flexible aerogel composite blankets as sorbent materials for automated oil capture and recovery: Cabot Thermal Wrap (TW) and Aspen Aerogels Spaceloft (SL). Uptake of crude oils (Iraq and Sweet Bryan Mound oils) was 8.0 ± 0.1 and 6.5 ± 0.3 g g(-1) for SL and 14.0 ± 0.1 and 12.2 ± 0.1 g g(-1) for TW, respectively, nearly twice as high as similar polyurethane- and polypropylene-based devices. Compound-specific uptake experiments and discrimination against water uptake suggested an adsorption-influenced sorption mechanism. Consistent with that mechanism, chemical extraction oil recoveries were 95 ± 2 (SL) and 90 ± 2% (TW), but this is an undesirable extraction route in decentralized oil cleanup efforts. In contrast, mechanical extraction routes are favorable, and a modest compression force (38 N) yielded 44.7 ± 0.5% initially to 42.0 ± 0.4% over 10 reuse cycles for SL and initially 55.0 ± 0.1% for TW, degrading to 30.0 ± 0.2% by the end of 10 cycles. The mechanical integrity of SL deteriorated substantially (800 ± 200 to 80 ± 30 kPa), whereas TW was more robust (380 ± 80 to 700 ± 100 kPa) over 10 uptake-and-compression extraction cycles.

9.
Clinical Medicine of China ; (12): 100-104, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-488479

RESUMO

Objective To evaluate the safety and effectiveness of mechanical thrombectomy with Solitaire AB stent in the treatment of large intracranial artery occlusions.Methods The calinical data of 15 patients with acute stroke(more than 3.5 h intravenous thrombolysis time window) who were carried out arterial embolectomy with Solitaire AB stent in the No.264th Hospital of the Chinese People's Liberation Army were retrospective analyzed.There were 11 cases of middle cerebral artery(MCA),2 cases of internal carotid artery (ICA),1 case of vertebral artery(VA) pluse basilar artery(BA),and 1 case of anterior artery(AA).The recanalization occluded situation and surgical complications were analyzed,NIHSS score of preoperatively and at discharge were compared.Results In 15 cases,there were 14 cases of totally recanalization,1 case of partial recanalization.Two case with MCA stenosis and 1 case with VA stenosis after the recanalization were accepted stent angioplasty,2 csase died.NIHSS score of 13 cases survival patients increased from (22.85±4.75) scores on admission to (4.39 ±3.67) scores out of hospital,and the difference was statistically sinificant(t=2.752,P <0.01).Conclusion The mechanical thrombectomy with Solitaire AB stent can get high recanalization rate,fewer complications and good clinical outcome on patients with large intracranial artery occlusions.For more than venous or arterial thrombolysis time window,the mechanical thrombectomy can be considered within the 8 h after comprehensive evaluation.

10.
J Cardiovasc Electrophysiol ; 26(3): 357-61, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25311643

RESUMO

Laser and radiofrequency energy-assisted lead extraction has greatly facilitated this complex procedure. Although success rates are high, in some instances alternate methods of extraction are required. In this review, we discuss techniques for femoral extraction of implanted leads and retained fragments. The major tools available, including commonly used snares and delivery tools, are discussed. We briefly describe combined internal jugular and femoral venous extraction approaches, as well as complimentary utilization of more than one technique via the femoral vein. Animated and procedural sequences are included to help the reader visualize the key components of these techniques.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Remoção de Dispositivo/métodos , Veia Femoral/cirurgia , Humanos
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