Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Carbohydr Polym ; 328: 121712, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220323

RESUMO

Recently, pre-formed V-type starch has become popular as a versatile carrier in encapsulation systems of containing starch-guest inclusion complexes (ICs). However, the differences in stabilizing and dissociating guests between ICs prepared by either the traditional method or the pre-formed "empty" helix method have not yet been elucidated. Here, starch-thymol ICs were prepared using the traditional high temperature-water method and the pre-formed method, covering different complexation temperatures and solvents, to compare the loading capacity, crystalline structure, thermal stability, and release properties. The highest content of thymol in ICs prepared by the pre-formed and the traditional method was 74.2 and 65.3 mg/g, respectively. Different from ICs prepared by the traditional method (V7-type crystal), ICs prepared by the pre-formed method mostly exhibited a V6a structure with larger crystallinities and a better short-range ordered structure. ICs prepared at 90 °C were type II complexes and efficiently protected thymol from rapid heat loss. A slow release was observed in both cases: about 45 % and 75 % of thymol were released from ICs prepared by the pre-formed and traditional methods, respectively, after two weeks of storage at 25 °C.

2.
Food Chem ; 411: 135509, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36682167

RESUMO

Heteroprotein complexes are formed by electrostatic interactions of oppositely charged proteins in a purely aqueous environment. Understanding the relationship between their structural and functional properties will contribute to their tailor-made applications. Therefore, this study investigated the protein conformation, assembling structure, and enzyme activity of soy protein isolate/lysozyme (SPI/LYS) complexes at mass ratios of 2:1 (soluble complex) and 1:1.3 (stoichiometric ratio). Electrostatic complexation increased the surface hydrophobicity of complexes. Their surface hydrophobicity decreased with increasing NaCl concentrations and reached the theoretical values at the critical salt concentration of 200 mM NaCl. Electrostatic complexation did not decrease the LYS activity (∼43,000 units/mg). SPI/LYS complexes exhibited flocculated structures in which the two proteins were unevenly distributed; these were typical amorphous complexes. High dilution disassembled these complexes over 5 µm into particles of ∼100 nm, and NaCl reduced the size of these particles. Immobilized water was detected in the complexes formed by particle flocculation.


Assuntos
Muramidase , Proteínas de Soja , Muramidase/química , Proteínas de Soja/química , Cloreto de Sódio , Conformação Proteica
3.
J Environ Manage ; 328: 116975, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36527801

RESUMO

Aerobic pre-treatment of liquid dairy manure has previously been reported as an effective nutrient export and emissions mitigation approach. The first objective of this study was to experimentally determine the optimal intermittent aeration ratio for nutrient recovery from liquid dairy manure through an on-site pilot-scale reactor to partially reduce the required energy for the aerobic process. The second objective was to theoretically investigate the total carbon footprints of direct manure spreading on croplands and permanent manure storage in open anaerobic lagoons in response to nutrient removal by the optimal determined intermittent aerobic treatment ratio. Four scenarios (S) were included; S1 was the traditional scenario of manure spread on croplands without the aerobic pre-treatment, S2 was the modified scenario of manure spread on croplands that included the aerobic pre-treatment, S3 was the traditional scenario of manure storage in lagoons, and S4 was the modified scenario of manure storage in lagoons that included the aerobic pre-treatment. The results showed that comparable nutrient removal efficiencies could be obtained with a 5:1 intermittent aeration ratio. Total nitrogen (TN) and total phosphorus (TP) were recovered were 41.5 ± 1.3% and 37.0 ± 4.0%, respectively, in ammonium sulfate and phosphorus-rich sludge, while 55.3 ± 1.4% of the chemical oxygen demand (COD) was removed. The estimated total carbon footprint for S1, S2, S3, and S4 were 24.4, 37.9, 45.3, and 45.9 kg CO2-eqton-1, respectively. However, the total carbon footprint of S2' and S4', which used renewable-based energy to run the reactor instead of fossil-based energy used in S2 and S4, were estimated to 29.5 and 37.5 kg CO2-eqton-1, respectively. Clearly, applying the aerobic pre-treatment increased the total carbon footprint of all cases except S4', in which the total carbon footprint was mitigated by -17.2%. Accordingly, the aerobic pre-treatment is only recommended in the case of S4' from a carbon footprint point of view although it is an effective nutrient recovery technology.


Assuntos
Pegada de Carbono , Esterco , Dióxido de Carbono/análise , Análise da Demanda Biológica de Oxigênio , Nitrogênio , Fósforo
4.
Carbohydr Polym ; 298: 120086, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241277

RESUMO

"Empty" V-type starch is a potential carrier for versatile applications in novel ways. This study provided a facile and efficient preparation method of excellent "empty" V-type starch, in which the ordered structure of the carrier was regulated by the complexation temperature without additional annealing treatment. Thymol was used as a model guest material to examine the relationship between the crystalline structure and loading capacity of V-type starch. Increasing the complexation temperature from 30 to 90 °C led to more perfect crystallites in the V-type starch, a significant increase in crystallinity from 25.2 % to 40.2 %, and an increase in enthalpy changes from 6.11 to 14.57 J/g. As the ordered structure contributed to improving the loading capacity of V-type starch, the V-type starch prepared at 90 °C (90-V) showed the highest encapsulation capacity (33.97 mg/g) for thymol. Our findings provide a new paradigm for preparing V-type starch facilely and efficiently.


Assuntos
Amido , Timol , Amido/química , Temperatura , Termodinâmica
5.
Food Funct ; 13(12): 6726-6736, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35661183

RESUMO

The interaction between epigallocatechin gallate (EGCG) and soy proteins at room temperature (25 °C) and after heating at 100 and 121 °C, and their effects on the inactivation of soybean trypsin inhibitors (STIs) in soymilk were investigated. The results of the nitroblue tetrazolium (NBT) staining assay showed that soy proteins can covalently bind to EGCG. The α/α' and A subunits in heated soymilk preferred to bind to EGCG because of their soluble state. More thiols were trapped when EGCG was added before thermal processing, and the free amino groups were depleted more with EGCG addition after heating. Circular dichroism and fluorescence spectroscopy showed that EGCG addition before or after heating induced different secondary and tertiary structural changes for soy proteins. The exposed aromatic amino acids preferred to react with EGCG before protein aggregation in the heating process. The random coil of soymilk proteins increased more when EGCG was added in soymilk after heating, resulting in more disordered structures in protein conformation. The binding between EGCG and soy proteins promoted protein aggregation, which was confirmed by the particle size distribution and gel electrophoresis. The trypsin and chymotrypsin inhibitory activity (TIA and CIA) in soymilk significantly reduced to 693 U mL-1 and 613 U mL-1, respectively, under the conditions of 2 mM EGCG addition after 100 °C heating for 10 min (p < 0.05). Consequently, the influence of EGCG on STI inactivation in soymilk only worked when EGCG was added after heating.


Assuntos
Catequina , Infecções Sexualmente Transmissíveis , Catequina/química , Catequina/farmacologia , Polifenóis/farmacologia , Agregados Proteicos , Proteínas de Soja/química , Glycine max/química , Chá , Inibidores da Tripsina/farmacologia
6.
Sci Total Environ ; 814: 152700, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34973327

RESUMO

Digestate (effluent of biogas plants) became the main bottleneck for biogas industry expansion because it often exceeds the capacity of surrounding croplands as fertilizer. Nutrients recovery from digestate is a promising solution for closing nutrients cycles and generating high value-added byproducts. In fact, numerous nutrients recovery technologies were reported and utilized for that purpose. However, each technology has optimum working conditions, while digestates have different characteristics due to the different substrates, digestion conditions, and handling methods. On the other hand, no protocol has been reported yet for selecting the optimal nutrients recovery technology or sequenced technologies for different digestates regarding their characteristics and the surrounding environmental conditions. In this study, an interactive flowchart was suggested and discussed for selecting the most appropriate technology or sequential techniques among the different alternatives. The whole digestate utilization technologies, solid-liquid separation technologies, liquid and solid processing technologies were included.


Assuntos
Biocombustíveis , Fertilizantes , Anaerobiose , Nutrientes
7.
J Agric Food Chem ; 69(37): 11043-11052, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34499500

RESUMO

This study aimed to investigate the effect of tea polyphenol extract (TPE) on the in vitro gastric digestion of soymilk. Fluorescence recovery after photobleaching was applied to measure pepsin diffusivity in soymilk. The characteristics of soymilk digesta were evaluated by gel electrophoresis, degree of hydrolysis (DH), molecular weight distribution, free amino acid analysis, particle size, antioxidant capacity, and trypsin/chymotrypsin inhibitor activity (TIA/CIA). The binding between soy proteins and tea polyphenols could significantly impair in vitro gastric digestion of soymilk by decreasing pepsin diffusivity from 91.3 to 70.3 µm2/s and DH from 17.13 to 13.93% with 1.2 mg/g TPE addition. Soymilk with 0.6 mg/g TPE addition exhibited low TIA/CIA and a strong antioxidant capacity in gastric digesta, which might be good for the following intestinal digestion. A better understanding of the effect of polyphenol on the digestion of protein-based food may be beneficial to innovation in food manufacturing.


Assuntos
Polifenóis , Proteínas de Soja , Digestão , Pepsina A , Chá
8.
J Agric Food Chem ; 69(28): 7948-7959, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34240870

RESUMO

Heteroprotein complex coacervate (HPCC) is a liquid-like protein concentrate produced by liquid-liquid phase separation. We revealed the protein dynamic exchange and thermodynamic mechanism of ß-conglycinin/lysozyme coacervate, and clarified the effect of HPCC on protein structure and activity. ß-conglycinin and lysozyme assembled into coacervate at pH 5.75-6.5 and assembled into amorphous precipitates at higher pH. As the pH dropped from 8 to 6, the number of binding sites of the complex decreased in half, and the desolvation degree corresponding to the entropy gain was greatly reduced, conducing to the formation of coacervates rather than precipitates. The coacervates achieved the unique dynamic exchange by exchanging proteins with the diluted phase, making the uniform distribution of proteins in coacervates. The lysozyme activity was completely retained in ß-conglycinin/lysozyme coacervates. These results proved that ß-conglycinin-based heteroprotein complex coacervate is a feasible method to encapsulate and enrich active proteins in a purely aqueous environment.


Assuntos
Globulinas , Muramidase , Antígenos de Plantas , Proteínas de Armazenamento de Sementes , Proteínas de Soja , Termodinâmica
9.
J Food Sci Technol ; 58(4): 1368-1377, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33746265

RESUMO

The effects of heat treatment on protein interaction, surface hydrophobicity, protein profile, amino acid composition, and in vitro digestibility of individual rice protein fractions were investigated. Heat treatment at 100 °C for 20 min had no negative effect on essential amino acids in rice protein. Surface hydrophobicity increased significantly with the increased heat treatment temperature. Moreover, free-thiol content decreased significantly with increased temperature and time extension. Hydrophobic interactions contributed to the heat-induced interaction of glutelin and prolamin. Intramolecular disulfide linkages participated in the heat-induced interaction of all rice-protein fractions. Heat treatment had no effects on the in vitro digestibility of glutelin, globulin, and albumin. Thus, the heat-induced interactions of glutelin, globulin, and albumin were not related to their digestibility. By contrast, the formation of intramolecular disulfide bonds and hydrophobic interactions in prolamin may reduce its digestibility by strengthening protein bodies-Is.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33602604

RESUMO

OBJECTIVE: The objective of this study was to compare the diagnostic performance of magnetic resonance imaging (MRI) and computed tomography (CT) in differentiating pleomorphic adenomas from Warthin tumors using radiomics. STUDY DESIGN: We retrospectively reviewed 626 patients who underwent preoperative MRI or CT for parotid tumor diagnosis. Patient groups were balanced by propensity score matching (PSM) and 123 radiomic features were extracted from tumor images. Radiomic signatures (rad-scores) were generated using a least absolute shrinkage and selection operator logistic regression model. The Canny edge detector was used to define tumor borders (border index). The diagnostic performance of rad-score and border index before and after PSM was evaluated with area under the receiver operating characteristic curve analysis. RESULTS: For differentiation of pleomorphic adenomas and Warthin tumors, rad-score and border index areas under the curve for MRI after PSM were 0.911 (95% confidence interval [CI], 0.871-0.951) and 0.716 (95% CI, 0.646-0.787), respectively; those for CT were 0.876 (95% CI, 0.829-0.923) and 0.608 (95% CI, 0.527-0.690), respectively. Tumor border index on MRI, but not CT, had superior diagnostic performance (P < .05); MRI- and CT-based rad-scores showed similar performance (P >.05). CONCLUSIONS: MRI is superior to CT for tumor margin examination; however, the radiomics features of both modalities showed no difference.


Assuntos
Adenoma Pleomorfo , Neoplasias Parotídeas , Adenoma Pleomorfo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neoplasias Parotídeas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Oral Radiol ; 37(4): 658-668, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33428106

RESUMO

OBJECTIVES: To explore the effectiveness of magnetic resonance image (MRI)-based biomarkers for identifying benign and malignant parotid tumors via diagnostic model analysis. METHODS: This retrospective study included 109 patients (development cohort and validation cohort) who underwent MRI preoperatively, including T1- and T2-weighted images. Parameters based on 2D or 3D texture analysis were extracted from tumor lesions by MaZda software, fisher discriminant and bootstrap method were used to perform parameter reduction, diagnostic models with the selected biomarkers were established along with clinical data, model performance (discrimination and calibration) was furtherly evaluated by internal and external validation, decision curve analysis was applied to measure the improvement of clinical benefits. RESULTS: S(5,5) Entrop, S(0,1) ASM, WavEnHH (s-4), S(1,1,0) Entropy and Perc.10% were significantly associated with the pathological diagnosis of parotid tumor (benign versus malignancy), when adding these biomarkers to the regression analysis, model performance significantly improved in the development cohort (likelihood-ratio-test; p < 0.05, with an increase of AUC from 0.72 (reference model) to 0.85), and these results were maintained in a small external validation cohort. Decision curve analysis indicated that clinical benefit was greater with the application of MRI-based biomarkers. CONCLUSIONS: MRI-based texture analysis is proven to be an effective tool in differentiating benign and malignant parotid tumors, preoperative diagnosis was improved with the selected biomarkers compared to the reference model.


Assuntos
Neoplasias Parotídeas , Biomarcadores , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Neoplasias Parotídeas/diagnóstico por imagem , Estudos Retrospectivos
12.
Adv Colloid Interface Sci ; 284: 102268, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32977143

RESUMO

Proteins are important components of foods, because they are one of the essential food groups, they have many functional properties that are very useful for modifying the physicochemical and textural properties of processed foods and possess many biological activities that are beneficial to human health. The process of heteroprotein complex coacervation (HPCC) combines two or more proteins through long-range coulombic interaction and specific short-range forces, creating a liquid-liquid colloid, with highly concentrated protein in the droplet phase and much more diluted-protein in the bulk phase. Coacervates possess novel, modifiable, physicochemical characteristics, and often exhibit the combined biological activities of the protein components, which makes them applicable to formulated foods and encapsulation carriers. This review discusses research progress in the field of HPCC in three parts: (1) the basic and innovative experimental methods and simulation tools for understanding the physicochemical behavior of these heteroprotein supramolecular architectures; (2) the influence of environmental factors (pH, mixing ratio, salts, temperature, and formation time) and intrinsic factors (protein modifications, metal-binding, charge anisotropy, and polypeptide designs) on HPCC; (3) the potential applications of HPCC materials, such as encapsulation of nutraceuticals, nanogels, emulsion stabilization, and protein separation. The wide diversity of possible combinations of proteins with different properties, endows HPCC materials with great potential for development into highly-innovation functional food ingredients.


Assuntos
Fenômenos Químicos , Alimentos , Proteínas/química , Proteínas/metabolismo , Alimento Funcional , Humanos
13.
Food Chem ; 309: 125614, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31678672

RESUMO

Effects of partial substitution of NaCl with KCl, MgCl2 or CaCl2 on oxidative characteristics of myofibrillar protein (MP) in a hydroxyl radical generating system and their heat-induced gel properties were investigated. Results indicated that MP oxidation is dependent upon the different chloride salt types and substitution degree. MP at 0.60 M NaCl was beneficial to protein unfolding and gel quality in the oxidative system. Increased formation of disulfide bonds affected the MP conformation and resulted in a large particle size and an aggregatednetworkofgel at the 50% substitution degree of KCl. The presence of CaCl2 or MgCl2 substitutes contributed to protein polymerization and insolubility. MP aggregation restrained the formation of dense and continuous gel networks during heating, and thus resulted in a low-grade gel. Ca2+ had more serious impact on gel properties than Mg2+, dependent on different cation effects. Substitution of 25% NaCl by KCl gave acceptable gel quality in MP.


Assuntos
Manipulação de Alimentos/métodos , Proteínas Musculares/química , Cloreto de Potássio/química , Cloreto de Sódio/química , Animais , Cloreto de Cálcio/química , Dissulfetos/química , Géis/química , Radical Hidroxila/química , Cloreto de Magnésio/química , Oxirredução , Tamanho da Partícula , Carne de Porco , Desdobramento de Proteína
14.
Sci Rep ; 9(1): 6914, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061512

RESUMO

Nanodiamonds hosting colour centres are a promising material platform for various quantum technologies. The fabrication of non-aggregated and uniformly-sized nanodiamonds with systematic integration of single quantum emitters has so far been lacking. Here, we present a top-down fabrication method to produce 30.0 ± 5.4 nm uniformly-sized single-crystal nanodiamonds by block copolymer self-assembled nanomask patterning together with directional and isotropic reactive ion etching. We show detected emission from bright single nitrogen vacancy centres hosted in the fabricated nanodiamonds. The lithographically precise patterning of large areas of diamond by self-assembled masks and their release into uniformly sized nanodiamonds open up new possibilities for quantum information processing and sensing.

15.
Food Sci Nutr ; 7(2): 608-616, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30847140

RESUMO

The effects of washing, soaking, and common domestic cooking methods (normal cooking, high-pressure cooking, and microwave cooking) on protein content, in vitro protein digestibility, and amino acid composition of japonica and indica rice were investigated. All processes in rice domestic cooking did not affect protein content. However, the gastric and gastrointestinal protein digestibilities decreased significantly after cooking. Protein solubility methods were used to observe the formation of disulfide bonds and hydrophobicity interactions after cooking. Disulfide bonds and hydrophobicity interactions were formed during cooking, and the cooking-induced disulfide bond cross-linking decreased the protein digestibility observably. Moreover, the solubility of 13 kDa prolamin subunit sharply decreased after cooking due to intramolecular disulfide bond cross-linking. Therefore, cooking-induced formation of intramolecular disulfide linkages might stabilize and strengthen the structure of protein body-I, which exhibited strong resistance to proteases, particularly pepsin. Cooking had limited effect on amino acids.

16.
Nat Commun ; 10(1): 109, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30631048

RESUMO

Controlling thermal radiation is central in a range of applications including sensing, energy harvesting, and lighting. The thermal emission spectrum can be strongly modified through the electromagnetic local density of states (EM LDOS) in nanoscale-patterned metals and semiconductors. However, these materials become unstable at high temperature, preventing improvements in radiative efficiency and applications such as thermophotovoltaics. Here, we report stable high-temperature thermal emission based on hot electrons (>2000 K) in graphene coupled to a photonic crystal nanocavity, which strongly modifies the EM LDOS. The electron bath in graphene is highly decoupled from lattice phonons, allowing a comparatively cool temperature (700 K) of the photonic crystal nanocavity. This thermal decoupling of hot electrons from the LDOS-engineered substrate opens a broad design space for thermal emission control that would be challenging or impossible with heated nanoscale-patterned metals or semiconductor materials.

17.
J Cell Biochem ; 120(3): 4644-4653, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30260023

RESUMO

Oral squamous cell carcinoma (OSCC), the most common pathological type of oral cancer, is still a frequent malignancy with unsatisfactory prognosis. Accumulating studies have proven some microRNAs (miRNAs) can function as oncogenes in OSCC by targeting tumor suppressors. In this study, we first investigated the expression and role of tumor suppressor bridging integrator-1 (BIN1) in OSCC tissues and cells. Our results indicated that BIN1 was low expressed in the OSCC tissues and cell lines (SCC6, SCC9, SCC25, HN4, and HN6) along with miR-211 was highly expressed in OSCC tissues and cell lines, and BIN1 overexpression could evidently inhibit their proliferation, migration, and invasion abilities. Next, we used bioinformation algorithms to predict the potential miRNA targeting BIN1 and chose miR-211 for further study. miR-211, a highly expressed miRNA in OSCC cells, could specifically bind with the 3'-untranslated region (3'-UTR) of BIN1 to trigger its degradation. Addition of miR-211 inhibitor could evidently suppress the malignant behaviors of OSCC cells by upregulating BIN1 expression and inhibit the activation of the EGFR/MAPK pathway. Taken together the findings of the study indicated that miR-211 mediated BIN1 downregulation had crucial significances in OSCC, suggesting the miR-211 might be a novel potential therapeutic target for the OSCC treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Carcinoma de Células Escamosas/metabolismo , Movimento Celular , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Proteínas Nucleares/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais , Invasividade Neoplásica
18.
Nat Nanotechnol ; 13(9): 797-801, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29892017

RESUMO

High sensitivity, fast response time and strong light absorption are the most important metrics for infrared sensing and imaging. The trade-off between these characteristics remains the primary challenge in bolometry. Graphene with its unique combination of a record small electronic heat capacity and a weak electron-phonon coupling has emerged as a sensitive bolometric medium that allows for high intrinsic bandwidths1-3. Moreover, the material's light absorption can be enhanced to near unity by integration into photonic structures. Here, we introduce an integrated hot-electron bolometer based on Johnson noise readout of electrons in ultra-clean hexagonal-boron-nitride-encapsulated graphene, which is critically coupled to incident radiation through a photonic nanocavity with Q = 900. The device operates at telecom wavelengths and shows an enhanced bolometric response at charge neutrality. At 5 K, we obtain a noise equivalent power of about 10 pW Hz-1/2, a record fast thermal relaxation time, <35 ps, and an improved light absorption. However the device can operate even above 300 K with reduced sensitivity. We work out the performance mechanisms and limits of the graphene bolometer and give important insights towards the potential development of practical applications.

19.
J Sci Food Agric ; 98(10): 3829-3835, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29363749

RESUMO

BACKGROUND: The health risk of heavy metals such as cadmium (Cd), arsenic (As) and lead (Pb) in rice can be assessed by their concentration and bioaccessibility. In this work, japonica cultivar Xinfeng 2 and indica cultivar T-You 15 were washed, soaked and cooked using three common domestic cooking methods. The present study investigated the effects of washing, soaking, normal cooking, high-pressure cooking and microwave cooking on the concentration, bioaccessibility and health risk of Cd, As and Pb in rice. RESULTS: Washing significantly reduced concentrations of Cd, As and Pb, and all three types of cooking reduced bioaccessibilities of these elements. No significant differences in bioaccessibility were observed among rice prepared with different cooking methods. Concentrations and bioaccessibilities of Cd, As and Pb highly affected the values of average daily dose, hazard quotient and lifetime cancer risk. High concentration and bioaccessibility cause As to pose non-carcinogenic and carcinogenic health risks to adults and children. Moreover, compared with adults, children have a high chance of exposure to non-carcinogenic and carcinogenic health risks. CONCLUSION: Washing and cooking of rice lowered the health risk by reducing Cd, As and Pb concentrations and bioaccessibilities respectively. © 2018 Society of Chemical Industry.


Assuntos
Arsênio/análise , Cádmio/análise , Manipulação de Alimentos/métodos , Chumbo/análise , Oryza/química , Arsênio/metabolismo , Disponibilidade Biológica , Cádmio/metabolismo , Culinária/instrumentação , Culinária/métodos , Contaminação de Alimentos/análise , Manipulação de Alimentos/instrumentação , Trato Gastrointestinal/metabolismo , Humanos , Chumbo/metabolismo , Oryza/metabolismo , Medição de Risco
20.
Nat Nanotechnol ; 12(12): 1124-1129, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29209014

RESUMO

One of the current challenges in photonics is developing high-speed, power-efficient, chip-integrated optical communications devices to address the interconnects bottleneck in high-speed computing systems. Silicon photonics has emerged as a leading architecture, in part because of the promise that many components, such as waveguides, couplers, interferometers and modulators, could be directly integrated on silicon-based processors. However, light sources and photodetectors present ongoing challenges. Common approaches for light sources include one or few off-chip or wafer-bonded lasers based on III-V materials, but recent system architecture studies show advantages for the use of many directly modulated light sources positioned at the transmitter location. The most advanced photodetectors in the silicon photonic process are based on germanium, but this requires additional germanium growth, which increases the system cost. The emerging two-dimensional transition-metal dichalcogenides (TMDs) offer a path for optical interconnect components that can be integrated with silicon photonics and complementary metal-oxide-semiconductors (CMOS) processing by back-end-of-the-line steps. Here, we demonstrate a silicon waveguide-integrated light source and photodetector based on a p-n junction of bilayer MoTe2, a TMD semiconductor with an infrared bandgap. This state-of-the-art fabrication technology provides new opportunities for integrated optoelectronic systems.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...