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1.
Sci Total Environ ; 791: 148412, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412385

RESUMO

To better manage pesticide pollution in surface soils, we introduced a first-order-kinetics-based screening model to evaluate the steady-state concentrations of pesticides in surface soils while considering degradation, volatilization, plant uptake, and precipitation processes. For each process, we developed a spatiotemporal-pattern-based model using spatiotemporal variables, including air temperature (TA), relative humidity (RHA), and rainfall intensity (IRA), to characterize the overall dissipation rates (kT) of pesticides in the soil. These dissipation rates were converted to fate factors (FFs), which are commonly used in life cycle analyses. The results indicate that, in general, the kT values increase with increasing TA and IRA and decrease with increasing RHA. This is because increased TA boosts the degradation, volatilization, and plant uptake processes, whereas increased RHA lowers the plant transpiration rate. Also, the simulation for over 700 pesticides indicated that the degradation process dominates the overall dissipation of most pesticides in the soil, and the volatilization process contributes the least. In addition, we simulated chlorpyrifos FFs for Brazil, China, the US, and the European Union (EU) using the annual average TA, RHA, and IRA values. The results indicate that, in general, Brazilian federal units have the smallest FFs and the narrowest simulated FF range because of their humid tropical climates. Meanwhile, the EU member states have the largest FFs and the widest FF range because of their range in locations. In addition, our simulated results show that the surface soils in the high-latitude regions could accumulate more chlorpyrifos than those in low-latitude regions because of the larger simulated FFs. Furthermore, we parameterized our model using 737 pesticides with the USEtox, thereby providing an alternative approach to simulate the steady-state concentration of pesticides in surface soils from the USEtox available data. The model developed herein is a useful screening tool for predicting pesticide concentrations in surface soil worldwide to improve soil and ecological health risk management.


Assuntos
Clorpirifos , Praguicidas , Poluentes do Solo , Praguicidas/análise , Solo , Poluentes do Solo/análise , Volatilização
2.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443346

RESUMO

A temperature dependence of saturated vapor pressure of isavuconazole (IVZ), an antimycotic drug, was found by using the method of inert gas-carrier transfer and the thermodynamic functions of sublimation were calculated at a temperature of 298.15 K. The value of the compound standard molar enthalpy of sublimation was found to be 138.1 ± 0.5 kJ·mol-1. The IVZ thermophysical properties-melting point and enthalpy-equaled 302.7 K and 29.9 kJ mol-1, respectively. The isothermal saturation method was used to determine the drug solubility in seven pharmaceutically relevant solvents within the temperature range from 293.15 to 313.15 K. The IVZ solubility in the studied solvents increased in the following order: buffer pH 7.4, buffer pH 2.0, buffer pH 1.2, hexane, 1-octanol, 1-propanol, ethanol. Depending on the solvent chemical nature, the compound solubility varied from 6.7 × 10-6 to 0.3 mol·L-1. The Hansen s approach was used for evaluating and analyzing the solubility data of drug. The results show that this model well-described intermolecular interactions in the solutions studied. It was established that in comparison with the van't Hoff model, the modified Apelblat one ensured the best correlation with the experimental solubility data of the studied drug. The activity coefficients at infinite dilution and dissolution excess thermodynamic functions of IVZ were calculated in each of the solvents. Temperature dependences of the compound partition coefficients were obtained in a binary 1-octanol/buffer pH 7.4 system and the transfer thermodynamic functions were calculated. The drug distribution from the aqueous solution to the organic medium was found to be spontaneous and entropy-driven.


Assuntos
Nitrilas/química , Piridinas/química , Temperatura , Triazóis/química , 1-Octanol/química , Varredura Diferencial de Calorimetria , Cristalização , Solubilidade , Solventes/química , Volatilização , Água/química
3.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360903

RESUMO

Despite the fact that many studies have examined the effectiveness of different gaseous postharvest treatments applied at low temperature to maintain table grape quality, the use of ethanol vapor has hardly been investigated. Thus, this work has studied the effectiveness of ethanol vapor-generating sachets in the maintenance of It 681-30 table grape quality, a new cultivar, during storage at low temperature and after the shelf-life period at 20 °C. To this end, various quality assessments have been carried out and the effect of the ethanol treatment on the expression of different genes (phenylpropanoids, transcription factors, PRs, and aquaporins) was determined. The results indicated that the application of ethanol vapor reduced the total decay incidence, weight loss, and the rachis browning index in It 681-30 grapes stored at 0 °C and after the shelf-life period at 20 °C, as compared to non-treated samples. Moreover, the modulation of STS7 and the different PR genes analyzed seems to play a part in the molecular mechanisms activated to cope with fungal attacks during the postharvest of It 681-30 grapes, and particularly during the shelf-life period at 20 °C. Furthermore, the expression of aquaporin transcripts was activated in samples showing higher weight loss. Although further work is needed to elucidate the role of ethanol in table grape quality, the results obtained in this work provide new insight into the transcriptional regulation triggered by ethanol treatment.


Assuntos
Temperatura Baixa , Etanol/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Qualidade dos Alimentos , Armazenamento de Alimentos/métodos , Frutas/efeitos dos fármacos , Gases/farmacologia , Vitis/efeitos dos fármacos , Aquaporinas/genética , Frutas/genética , Expressão Gênica/efeitos dos fármacos , Reação de Maillard/efeitos dos fármacos , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Transcrição Genética/efeitos dos fármacos , Vitis/genética , Volatilização
4.
Chemosphere ; 277: 130233, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34384170

RESUMO

Hydrothermal carbonization (HTC) is known as a green biomass conversion technology. However, it often suffers from the issue of disposing hydrothermal carbonization aqueous products (HCAP). Based on the characterization and composition of acidic HCAP, a rice paddy soil column experiment was conducted to observe the effects of HCAP on ammonia (NH3) volatilization form paddy soil and rice yield. The experiment was designed with five treatments. HCAPs were produced at 220 °C and (SHC220-L) and 260 °C (SHC260-L) derived from poplar sawdust, HCAP produced at 220 °C (WHC220-L) and 260 °C (WHC260-L) derived from wheat straw, and a control group without HCAP application (termed CKU hereafter). The results showed that HCAP treatments increased the rice yield by 4.30%-26.0% compared to CKU. HACPs prepared at lower temperatures (SHC220-L and WHC220-L) mitigated the cumulative NH3 volatilization by 11.2% and 7.6%, respectively, and mitigated yield-scale NH3 volatilization (cumulative NH3 volatilization/total yield) by 14.2% âˆ¼ 22.4%. HCAP significantly improved the N use efficiency of rice. We found that the NH3 volatilization was related to NH4+-N concentration and pH of surface water, soil TOC and NH4+-N oxidation functional genes. This study implied that HCAP could be potentially used as a liquid fertilizer, which will be a potential substitute for chemical N fertilizers. There is still a long way before HCAP can be applied in full-scale for N fertilizer reduction and waste recycle.


Assuntos
Amônia , Oryza , Agricultura , Amônia/análise , Fertilizantes/análise , Nitrogênio/análise , Solo , Volatilização , Água
5.
Huan Jing Ke Xue ; 42(7): 3451-3457, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212672

RESUMO

Hydrochar can mitigate ammonia volatilization when applied in paddy fields due to its acidity and adsorption property. To realize the recycling of agricultural biowaste as well as the control of nutrient loss from paddy fields, a simulation soil-column experiment with wheat straw hydrochar (WHC) and water-washed hydrochar (W-WHC) was conducted to evaluate the performance of rice yield and ammonia volatilization from paddy fields. The results showed that WHC and W-WHC applied in paddy fields both increased the rice yield and the increased effect at low application rate (0.5%) was higher than that at high application rate (1.5%). In comparison with the control treatment (CKU), the rice yields achieved from low application rate treatments for WHC and W-WHC increased by 17.16% and 20.20% respectively. Except for the equal emission rate between W-WHC with low application rate and CKU treatments, hydrochar (WHC, W-WHC) addition reduced the ammonia volatilization from paddy fields when compared with the CKU. Among them, the ammonia volatilization levels from low-application WHC and high-application W-WHC treatments were significantly lower than that from the CKU treatment, reduced by 31.01% and 17.40%, respectively. Based on the analysis of ammonia volatilization during different fertilization stages, the control effect of hydrochar addition on ammonia volatilization was mainly benefited from tillering and panicle fertilizer stages. The change in the nitrogen concentration of surface water at the tillering fertilizer stage and in pH at the panicle fertilizer stage with the addition of hydrochar was the main driving factor for the reduction in ammonia volatilization. The results show that sufficient amounts of hydrochar derived from wheat straw application can increase crop yield while reducing ammonia volatilization from paddy fields. This method provides an effective route for recycling agricultural biowastes.


Assuntos
Amônia , Oryza , Amônia/análise , Fertilizantes/análise , Nitrogênio/análise , Solo , Triticum , Volatilização
6.
Molecules ; 26(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34299397

RESUMO

We followed a comparative approach to investigate how heavy vacuum gas oil (HVGO) affects the expression of genes involved in biosurfactants biosynthesis and the composition of the rhamnolipid congeners in Pseudomonas sp. AK6U. HVGO stimulated biosurfactants production as indicated by the lower surface tension (26 mN/m) and higher yield (7.8 g/L) compared to a glucose culture (49.7 mN/m, 0.305 g/L). Quantitative real-time PCR showed that the biosurfactants production genes rhlA and rhlB were strongly upregulated in the HVGO culture during the early and late exponential growth phases. To the contrary, the rhamnose biosynthesis genes algC, rmlA and rmlC were downregulated in the HVGO culture. Genes of the quorum sensing systems which regulate biosurfactants biosynthesis exhibited a hierarchical expression profile. The lasI gene was strongly upregulated (20-fold) in the HVGO culture during the early log phase, whereas both rhlI and pqsE were upregulated during the late log phase. Rhamnolipid congener analysis using high-performance liquid chromatography-mass spectrometry revealed a much higher proportion (up to 69%) of the high-molecularweight homologue Rha-Rha-C10-C10 in the HVGO culture. The results shed light on the temporal and carbon source-mediated shifts in rhamonlipids' composition and regulation of biosynthesis which can be potentially exploited to produce different rhamnolipid formulations tailored for specific applications.


Assuntos
Proteínas de Bactérias/metabolismo , Gases/farmacologia , Glicolipídeos/biossíntese , Glicosiltransferases/metabolismo , Óleos Voláteis/farmacologia , Pseudomonas/metabolismo , Percepção de Quorum , Pseudomonas/efeitos dos fármacos , Pseudomonas/crescimento & desenvolvimento , Ramnose/metabolismo , Tensoativos/farmacologia , Volatilização
7.
Molecules ; 26(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299454

RESUMO

In this study, a new broth macrodilution volatilization method for the simple and rapid determination of the antibacterial effect of volatile agents simultaneously in the liquid and vapor phase was designed with the aim to assess their therapeutic potential for the development of new inhalation preparations. The antibacterial activity of plant volatiles (ß-thujaplicin, thymohydroquinone, thymoquinone) was evaluated against bacteria associated with respiratory infections (Haemophilus influenzae, Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes) and their cytotoxicity was determined using a modified thiazolyl blue tetrazolium bromide assay against normal lung fibroblasts. Thymohydroquinone and thymoquinone possessed the highest antibacterial activity against H. influenzae, with minimum inhibitory concentrations of 4 and 8 µg/mL in the liquid and vapor phases, respectively. Although all compounds exhibited cytotoxic effects on lung cells, therapeutic indices (TIs) suggested their potential use in the treatment of respiratory infections, which was especially evident for thymohydroquinone (TI > 34.13). The results demonstrate the applicability of the broth macrodilution volatilization assay, which combines the principles of broth microdilution volatilization and standard broth macrodilution methods. This assay enables rapid, simple, cost- and labor-effective screening of volatile compounds and overcomes the limitations of assays currently used for screening of antimicrobial activity in the vapor phase.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Administração por Inalação , Antibacterianos/análise , Bactérias/efeitos dos fármacos , Benzoquinonas/administração & dosagem , Benzoquinonas/farmacologia , Haemophilus influenzae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Monoterpenos/administração & dosagem , Monoterpenos/farmacologia , Óleos Voláteis/química , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Timol/administração & dosagem , Timol/análogos & derivados , Timol/farmacologia , Tropolona/administração & dosagem , Tropolona/análogos & derivados , Tropolona/farmacologia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia , Volatilização
8.
Talanta ; 233: 122490, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215111

RESUMO

In natural environments, Acid Volatile Sulfides (AVS) contained in anoxic waters or sediments, are composed of dissolved sulfides and neo-formed sulfides colloids or particles. Under acidic addition, AVS emit hydrogen sulfide gas and release the so-called simultaneously extracted metals (SEM). The measurement of AVS coupled with that of the SEM enables to evaluate the metal trapping capacity of sulfides in the environment. Because AVS are extremely reactive to oxidation, the most accurate methodology to quantify AVS and SEM requires to be able to process the samples extraction on-site, directly after sampling and avoiding oxygen exposure. However, most of available systems are based on glassware 'purge and trap' techniques developed for the laboratory and are not often adapted to field studies. In these systems, AVS extraction time can range from 30 min to 3 h with relative standard deviation from 7 to 44%. In this study, we developed a new 'purge and trap' system designed for both laboratory use and field AVS/SEM extractions. The system is optimized with a shortened extraction time, miniaturized, unbreakable, easy and reproducible to develop parallel extraction benches. Analytical yields, precision and stability have been improved, allowing to reduce the extraction time to 1 h with an absolute quantification limit of 0.12 µmol S(-II) with a relative standard deviation between 7 and 11% and under a complete extraction efficiency.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Laboratórios , Metais , Metais Pesados/análise , Sulfetos/análise , Volatilização , Poluentes Químicos da Água/análise
9.
Talanta ; 233: 122516, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215131

RESUMO

A fast, low-cost and sensitive method for the determination of trace cadmium was developed by using a miniaturized dielectric barrier discharge microplasma atomic emission spectrometer coupled with a tungsten coil (W-coil) for on-line hydride generation trapping-electrothermal vaporization. Total sample throughput can be greatly improved through the adoption of a horizontally fixed W-coil and the flow injection mode. In addition, the horizontally fixed W-coil and an inserted quartz capillary for on-line trapping contributed to stable and good signal even at a high gas flow rate when volatile cadmium species were trapped, and less sample-consuming and time-saving can be realized in this work. Compared to direct injection, the sensitivity and the LOD were improved by 29- and 38-fold, respectively. The proposed method provides a promising approach to develop a miniaturized instrumentation for highly sensitive detection of trace elements.


Assuntos
Cádmio , Oligoelementos , Espectrofotometria Atômica , Oligoelementos/análise , Tungstênio , Volatilização
10.
Molecules ; 26(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206603

RESUMO

The vaporization enthalpy, and vapor pressure as a function of temperature of N-ethylamphetamine, a substance used in the 1950s as an appetite suppressant and more currently abused as a designer drug, is reported. Its physical properties are compared to those of S (+)-N-methamphetamine, a substance whose physiological properties it mimics. A vaporization enthalpy of (62.4 ± 4.4) kJ·mol-1 and vapor pressure of (19 ± 11) Pa at T = 298.15 K has been evaluated by correlation gas chromatography. Results are compared to estimated values and to the limited amount of experimental property data available.


Assuntos
Anfetaminas/química , Modelos Químicos , Termodinâmica , Pressão de Vapor , Cromatografia Gasosa , Volatilização
11.
Sci Total Environ ; 790: 148058, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34091340

RESUMO

Agricultural non-point source pollution has become the main pollution source in China. Ammonia (NH3) volatilization is one of the main factors of agricultural non-point source pollution. Slow-release nitrogen fertilizer (S) has been widely recognized as an efficient management measure to increase crop yields and mitigate NH3 volatilization. However, few studies have reported the effects of urea (U) blended with slow-release nitrogen fertilizer (UNS) on maize yield and NH3 volatilization under dryland farming conditions. A two-season field experiment with U, S and various blending ratios of U and S (UNS) under two N application rates (N1: 180 kg N ha-1, N2: 240 kg N ha-1) was conducted to determine their effects on maize yield, NH3 volatilization and residual soil NO3--N. The results showed that UNS substantially reduced NH3 volatilization compared with U, primarily because of the relatively low soil pH and electrical conductivity, and the relatively high soil organic matter. UNS significantly increased dry matter, grain yield, N uptake and N use efficiency (NUE), but reduced residual soil NO3--N compared with U and S. Among UNS treatments, the blending ratio of U and S at 3:7 (UNS2) was most effective in improving maize yield and NUE, while mitigating NH3 volatilization and soil NO3--N leaching. N1 not only reduced N losses, but also increased NUE compared with N2. In conclusion, UNS2N1 is recommended as the best N fertilizer application strategy for the sustainable production of dryland maize in northwest China.


Assuntos
Amônia , Fertilizantes , Agricultura , Amônia/análise , China , Fertilizantes/análise , Nitrogênio/análise , Solo , Ureia , Volatilização , Zea mays
12.
Forensic Sci Int ; 325: 110871, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34171546

RESUMO

This work presents a pseudo-operational study on plastic bags for the detection of latent fingermarks with various types of cyanoacrylates, including the two-step process with basic yellow 40 (BY40) staining and one-step fluorescent cyanoacrylates, Lumicyano and Polycyano. The use of longwave reflected UV (LWRUV) was employed as part of sequential development for all processes; however, detected marks were not unique as subsequent BY40 staining detected these marks as well. The use of BY40 in the sequence is very important, as without its inclusion many fingermarks would be missed. The study also investigated the use of a standard glass camera lens for LWRUV imaging and compared observations to a specific crystal quartz lens designed for UV imaging. The standard glass lens was able to detect all the marks detected with the crystal quartz lens. Lumicyano detected the lowest overall number of marks and both one-step fluorescent cyanoacrylate processes yielded less marks when compared to the two-step process; however, the use of BY40 after Lumicyano and Polycyano resulted in an increase of detected fingermarks. The use of BY40 did not have a major detrimental effect on subsequent LWRUV imaging, although there was no added evidential value.


Assuntos
Cianoacrilatos , Dermatoglifia , Raios Ultravioleta , Corantes , Fluorescência , Humanos , Plásticos , Volatilização
13.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073256

RESUMO

Sensory interactions exist between 3-alkyl-2-methoxypyrazines and various volatiles in wines. In this study, the binary blending of Cabernet Franc wines containing high levels of MPs and three monovarietal red wines with two proportions was conducted after fermentation. Volatiles were detected by gas chromatography-mass spectrometry (GC-MS), and wines were evaluated by quantitative descriptive analysis at three-month intervals during six-month bottle aging. Results showed blending wines exhibited lower intensity of 'green pepper', especially CFC samples blended by Cabernet Sauvignon wines with an even higher concentration of 3-isobutyl-2-methoxypyrazine (IBMP). Based on Pearson correlation analysis, acetates could promote the expression of 'tropical fruity' and suppress 'green pepper' caused by IBMP. Positive correlation was observed among 'green pepper', 'herbaceous', and 'berry'. The concentration balance between IBMP and other volatiles associated with 'green pepper' and fruity notes was further investigated through sensory experiments in aroma reconstitution. Higher pleasant fruity perception was obtained with the concentration proportion of 1-hexanol (1000 µg/L), isoamyl acetate (550 µg/L), ethyl hexanoate (400 µg/L), and ethyl octanoate (900 µg/L) as in CFC samples. Blending wines with proper concentration of those volatiles would be efficient to weaken 'green pepper' and highlight fruity notes, which provided scientific theory on sensory modification of IBMP through blending technique.


Assuntos
Análise de Alimentos/métodos , Pirazinas/análise , Vinho/análise , Acetatos , Adulto , Feminino , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Odorantes , Análise de Componente Principal , Reprodutibilidade dos Testes , Vitis/química , Compostos Orgânicos Voláteis , Volatilização , Adulto Jovem
14.
Molecules ; 26(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063887

RESUMO

The present work describes the use of Centrifugal Partition Chromatography (CPC) for the bio-guided isolation of repellent active volatile compounds from essential oils. Five essential oils (EOs) obtained from three Pinus and two Juniperus species were initially analyzed by gas chromatography-mass spectrometry (GC/MS) and evaluated for their repellent properties against Aedes albopictus. The essential oil from needles of P. pinea (PPI) presented the higher activity, showing 82.4% repellency at a dose of 0.2 µL/cm2. The above EO, together with the EO from the fruits of J. oxycedrus subsp. deltoides (JOX), were further analyzed by CPC using the biphasic system n-Heptane/ACN/BuOH in ratio 1.6/1.6/0.2 (v/v/v). The analysis of PPI essential oil resulted in the recovery of (-)-limonene, guaiol and simple mixtures of (-)-limonene/ß-pheladrene, while the fractionation of JOX EO led to the recovery of ß-myrcene, germacrene-D, and mixtures of α-pinene/ß-pinene (ratio 70/30) and α-pinene/germacrene D (ratio 65/45). All isolated compounds and recovered mixtures were tested for their repellent activity. From them, (-)-limonene, guaiol, germacrene-D as well the mixtures of (-)-limonene/ß-pheladrene presented significant repellent activity (>97% repellency) against Ae. albopictus. The present methodology could be a valuable tool in the effort to develop potent mosquito repellents which are environmentally friendly.


Assuntos
Aedes/efeitos dos fármacos , Cromatografia/métodos , Repelentes de Insetos/isolamento & purificação , Animais , Bioensaio , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Repelentes de Insetos/administração & dosagem , Repelentes de Insetos/farmacologia , Juniperus/química , Óleos Voláteis/química , Pinus/química , Volatilização
15.
Int J Biol Macromol ; 184: 50-56, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34116090

RESUMO

Sorghum steaming properties are important for both flavor and brewing efficiency of baijiu (Chinese alcohol liquor). However, it is currently unclear with respects to structural factors that affect sorghum steaming properties during baijiu production. In this study, starch fine molecular structures were characterized by size-exclusion chromatography and fluorophore-assisted carbohydrate electrophoresis for 8 sorghum varieties used in baijiu production. Starch crystalline structures and ordering of double helices were characterized by the X-ray diffraction and differential scanning calorimetry. Results showed that only small differences were observed for starch molecular size distributions and chain-length distributions in the raw sorghum flour. Of significance, the leached starch content and molecular size during steaming was very different among these sorghum varieties. Furthermore, Spearman correlation analysis showed that there was no significant correlation between starch fine structural parameters with the leached starch content. On the other hand, the correlation analysis showed that leached starch molecular size was negatively correlated with starch crystallinity, while positively correlated with the onset and peak gelatinization temperatures. It is concluded that the sorghum steaming property is controlled by the starch crystalline structures instead of starch fine molecular structures. These results could help the baijiu industry to produce baijiu with more desirable properties.


Assuntos
Álcoois/química , Sorghum/química , Amido/química , Animais , Cromatografia em Gel , Cristalografia por Raios X , Estrutura Molecular , Peso Molecular , Volatilização , Difração de Raios X
16.
J Food Sci ; 86(7): 3023-3032, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34146407

RESUMO

Kiwifruit contains abundant nutritive compounds and is highly favored by the consumers worldwide. Therefore, detailed metabolic profiling is important to provide theoretic basis for the improvement of kiwifruit quality. In this study, the levels of volatiles, carotenoids, and mineral elements in the flesh of 17 kiwifruit accessions were evaluated. Acids and esters were the main volatiles in kiwifruit. During these 17 kiwifruit accessions, "Chenhong," three "Jinyan," and two "Guichang" germplasms were specifically rich in aromatic esters, which might be associated with their special taste. The main carotenoids were lutein, ß-carotene, and zeaxanthin, and their levels were also genotype specific, with the green-fleshed "Guichang" having the highest level of carotenoids, and red-fleshed "Fuhong" and "Chenhong" being rich in zeaxanthin. Partial correlation analysis showed that the contents of some mineral elements were significantly correlated with those of specific volatiles and carotenoids, indicating the impacts of mineral elements on the accumulation of volatiles and carotenoids in the kiwifruit flesh. These results indicated that the contents of carotenoids and volatiles seemed to be affected by mineral elements and also provided a new potential method for improving fruit flavor quality in production.


Assuntos
Actinidia/metabolismo , Carotenoides/química , Frutas/química , Minerais/química , Actinidia/química , Actinidia/classificação , Actinidia/genética , Carotenoides/metabolismo , Frutas/classificação , Frutas/genética , Frutas/metabolismo , Genótipo , Minerais/metabolismo , Volatilização
17.
Front Public Health ; 9: 679475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095078

RESUMO

This study investigates the drivers of the Standard & Poor's (S&P) 500 equity returns during the COVID-19 crisis era. The paper considers various determinants of the equity returns from December 31, 2019, to February 19, 2021. It is observed that the United States Dollar (USD) and the volatility indices (VIX) negatively affect the S&P 500 equity returns. However, the newspaper-based infectious disease "equity market volatility tracker" is positively associated with the stock market returns. These results are robust to consider both the ordinary least squares (OLS) and the least angle regression (LARS) estimators.


Assuntos
COVID-19 , Doenças Transmissíveis , Humanos , Investimentos em Saúde , SARS-CoV-2 , Estados Unidos , Volatilização
18.
Chemosphere ; 280: 130593, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33932907

RESUMO

With a narrow margin between beneficial and toxic effects, selenium (Se) is of great concern due to its increasing level in aquatic environments. The accumulation and transformation of Se by the cyanobacterium Microcystis aeruginosa and effects of nutrients, particularly sulfate, were investigated. The nutrient-deprived cyanobacterium removed water-borne selenate (82.2 ± 0.93%) faster than selenite (58.9 ± 1.77%), with 86.0 ± 1.41% and 77.2 ± 1.00%, respectively, of the Se accumulated in the biomass and the rest volatilized. When supplied with excess nutrients, the Se accumulation and volatilization rates were significantly inhibited, with the removal efficiency dropping to 50.2 ± 2.59% and 7.37 ± 0.93% for selenite and selenate, respectively. When M. aeruginosa was tested with inadequate, appropriate, and adequate levels of sulfate, Se uptake decreased with increasing sulfate concentrations, particularly for selenate (from 34.1 to 4.81%). Using X-ray absorption near-edge structure to speciate biomass Se, selenite and selenate were transformed to organo-Se (87.3-100%), with or without nutrients present, suggesting M. aeruginosa could efficiently reduce Se oxyanions to more bioavailable forms. With increasing sulfate levels (5.0 and 10.0 mg S/L), percentages of SeMet converted from selenite decreased by 28.2-33.0%, with 19.1-33.2% as elemental Se, while organo-Se remained dominant (93.6-95.1%) in selenate-treated M. aeruginosa. Transmission electron microscopy shows structural damage in the cell wall at exposure to selenite (1600 µg Se/L), with the intracellular structure intact. To prevent Se biomagnification along aquatic food chains, the Se-laden biomass was combusted as a post-treatment, leading to a significant reduction in Se content (∼99.2%) and Se bioavailability, with inorganic Se (45.0-70.5%) predominant in the residue.


Assuntos
Microcystis , Compostos de Selênio , Selênio , Biomassa , Ácido Selênico , Volatilização
19.
PLoS One ; 16(5): e0251872, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34010337

RESUMO

BACKGROUND: As the SARS-CoV-2 pandemic accelerates, the supply of personal protective equipment remains under strain. To combat shortages, re-use of surgical masks and filtering facepiece respirators has been recommended. Prior decontamination is paramount to the re-use of these typically single-use only items and, without compromising their integrity, must guarantee inactivation of SARS-CoV-2 and other contaminating pathogens. AIM: We provide information on the effect of time-dependent passive decontamination (infectivity loss over time during room temperature storage in a breathable bag) and evaluate inactivation of a SARS-CoV-2 surrogate and a non-enveloped model virus as well as mask and respirator integrity following active multiple-cycle vaporised hydrogen peroxide (VHP), ultraviolet germicidal irradiation (UVGI), and dry heat (DH) decontamination. METHODS: Masks and respirators, inoculated with infectious porcine respiratory coronavirus or murine norovirus, were submitted to passive decontamination or single or multiple active decontamination cycles; viruses were recovered from sample materials and viral titres were measured via TCID50 assay. In parallel, filtration efficiency tests and breathability tests were performed according to EN standard 14683 and NIOSH regulations. RESULTS AND DISCUSSION: Infectious porcine respiratory coronavirus and murine norovirus remained detectable on masks and respirators up to five and seven days of passive decontamination. Single and multiple cycles of VHP-, UVGI-, and DH were shown to not adversely affect bacterial filtration efficiency of masks. Single- and multiple UVGI did not adversely affect respirator filtration efficiency, while VHP and DH induced a decrease in filtration efficiency after one or three decontamination cycles. Multiple cycles of VHP-, UVGI-, and DH slightly decreased airflow resistance of masks but did not adversely affect respirator breathability. VHP and UVGI efficiently inactivated both viruses after five, DH after three, decontamination cycles, permitting demonstration of a loss of infectivity by more than three orders of magnitude. This multi-disciplinal approach provides important information on how often a given PPE item may be safely reused.


Assuntos
COVID-19/metabolismo , Descontaminação/métodos , Peróxido de Hidrogênio/farmacologia , Norovirus/efeitos dos fármacos , Equipamento de Proteção Individual/provisão & distribuição , SARS-CoV-2/efeitos dos fármacos , Anti-Infecciosos/farmacologia , COVID-19/epidemiologia , COVID-19/virologia , Reutilização de Equipamento , Temperatura Alta , Humanos , Máscaras/microbiologia , Norovirus/isolamento & purificação , Pandemias , Equipamento de Proteção Individual/microbiologia , Dispositivos de Proteção Respiratória/microbiologia , SARS-CoV-2/isolamento & purificação , Raios Ultravioleta , Terapia Ultravioleta , Ventiladores Mecânicos/microbiologia , Volatilização
20.
Forensic Sci Int ; 324: 110804, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34000619

RESUMO

The development of fingermarks is an important step in visualizing ridge patterns for individualization purposes. Immunolabeling can be applied to fingermarks to selectively and sensitively detect antigens in fingermarks, and can be used as a developing method to visualize fingermarks. In this study we investigated single (the detection of one antigen) and multiple targeting approaches (the detection of multiple antigens simultaneously) to improve fingermark development. The detection of dermcidin, an antimicrobial peptide, was used as the gold standard to compare single and multi-target detection of keratins, albumin and/or dermcidin. Single detection of dermcidin and albumin mostly resulted in clear ridge details and/or pore detection, whereas the single keratin detection resulted in a poor visualization of the fingermarks. The multi-target approach in which both dermcidin and albumin were targeted, resulted in improved fingermark development compared to single dermcidin detection. Therefore, we recommend the use of multi-target detection consisting of anti-dermcidin and anti-albumin when using immunolabeling as fingermark development technique. Additionally, the optimized multi-target approach was tested as a pre- and post-development technique in combination with powder dusting and cyanoacrylate fuming. Immunolabeling has not been implemented yet in forensic case work, however we expect that immunolabeling can be used to redevelop poorly developed and/or smudged fingermarks in the nearby future. Currently, an ongoing pilot-study is being conducted in collaboration with the Dutch police.


Assuntos
Dermatoglifia , Imuno-Histoquímica , Cianoacrilatos , Humanos , Queratinas/análise , Peptídeos/análise , Albumina Sérica/análise , Volatilização
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