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1.
Front Psychiatry ; 13: 897175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311518

RESUMO

Postpartum Depression (PPD) is a burden on women's mental health after delivery, predominantly occurring in the 1st year. PPD poses a threat to the mother's life and affects the quality of childcare. Early detection by family members of depressive symptoms is critical. This study aimed to examine the role of family members in reporting depressive symptoms of PPD among new mothers. A cross-sectional study was conducted, where 56 family members were asked to report depressive symptoms observed in new mothers. At the same time, the new mothers were also screened for PPD using the Edinburgh Postpartum Depression Scale (EPDS). Binary logistic regression was performed. Depressive symptoms of new mothers reported by family members, including emotional and behavioral disturbance, being under stress, high anxiety, isolation, changing lifestyle, and inability to take care of their children, were found as predictors of PPD.

2.
J Oleo Sci ; 67(5): 617-626, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29628489

RESUMO

Candlenut oil (CNO) is a potentially new feedstock for biodiesel (BDF) production. In this paper, a two-step co-solvent method for BDF production from CNO was examined. Firstly, esterification of free fatty acids (FFAs) (7 wt%) present in CNO was carried out using a co-solvent of acetonitrile (30 wt%) and H2SO4 as a catalyst. The content of FFAs was reduced to 0.8 wt% in 1 h at 65°C. Subsequent transesterification of the crude oil produced was carried out using a co-solvent of acetone (20 wt%) and 1 wt% potassium hydroxide (KOH). Ester content of 99.3% was obtained at 40°C in 45 min. The water content in BDF was 0.023% upon purification using vacuum distillation at 5 kPa. The components of CNO BDF were characterized using a Fourier-transform infrared spectrometry and gas chromatography-flame ionization detector. The physicochemical properties of BDF satisfied the ASTM D6751-02 standard. The gaseous exhaust emissions from the diesel engine upon combustion of the BDF blends (B0-B100) with petrodiesel were examined. The emissions of carbon monoxide and hydrocarbons were clearly lower, but that of nitrogen oxides was higher in comparison to those from petro-diesel.


Assuntos
Aleurites , Biocombustíveis , Gases , Óleos de Plantas/química , Solventes/química , Acetona/química , Monóxido de Carbono , Catálise , Fenômenos Químicos , Esterificação , Ácidos Graxos não Esterificados/química , Ionização de Chama , Hidrocarbonetos , Hidróxidos/química , Óxidos de Nitrogênio , Compostos de Potássio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfúricos/química , Temperatura , Água
3.
Rev Sci Instrum ; 88(6): 065105, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28667961

RESUMO

This work focuses on design, construction, and optimization of configuration of a novel high voltage pulse power source for large-scale dielectric barrier discharge (DBD) generation. The pulses were generated by using the high-speed switching characteristic of an inexpensive device called silicon diodes for alternating current and the self-terminated characteristic of DBD. The operation started to be powered by a primary DC low voltage power supply flexibly equipped with a commercial DC power supply, or a battery, or DC output of an independent photovoltaic system without transformer employment. This flexible connection to different types of primary power supply could provide a promising solution for the application of DBD, especially in the area without power grid connection. The simple modular structure, non-control requirement, transformer elimination, and a minimum number of levels in voltage conversion could lead to a reduction in size, weight, simple maintenance, low cost of installation, and high scalability of a DBD generator. The performance of this pulse source has been validated by a load of resistor. A good agreement between theoretically estimated and experimentally measured responses has been achieved. The pulse source has also been successfully applied for an efficient DBD plasma generation.

4.
J Agric Food Chem ; 65(24): 4897-4904, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28541677

RESUMO

Alkaline treatment (Alk) combined with ultrasound-assisted extraction (UAE) (Alk+UAE) was examined as a means of extracting tocols and γ-oryzanol from rice bran into an organic phase while simultaneously recovering ferulic acid into an aqueous phase. The tocols and γ-oryzanol/ferulic acid yields were determined using high-performance liquid chromatography with fluorescence and UV detection. The effects of extraction conditions were evaluated by varying the Alk treatment temperature and extraction duration. The maximum yields of tocols and γ-oryzanol were obtained at 25 °C over a time span of 30 min. When the temperature was increased to 80 °C, the yield of ferulic acid increased dramatically, whereas the recovery of γ-oryzanol slightly decreased. Employing the Alk+UAE procedure, the recovered concentrations of tocols, γ-oryzanol, and ferulic acid were in the ranges of 146-518, 1591-3629, and 352-970 µg/g, respectively. These results are in good agreement with those reported for rice bran samples from Thailand.


Assuntos
Fracionamento Químico/métodos , Ácidos Cumáricos/isolamento & purificação , Oryza/química , Fenilpropionatos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ultrassom/métodos , Ácidos Cumáricos/química , Fenilpropionatos/química , Extratos Vegetais/química , Temperatura
5.
Bioresour Technol ; 173: 309-316, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25310867

RESUMO

Biodiesel fuels (BDFs) was successfully produced from Vietnamese Jatropha curcas oil with high content of free fatty acids (FFAs) in two stages. In the first stage, the esterification process was carried out with the optimal conditions as follows; a methanol-to-FFAs molar ratio of 6:1, 1 wt% H2SO4, at a temperature of 65 °C, and using 30% (wt/wt) acetonitrile as co-solvent. This step reduced the concentration of FFAs in the reaction mixture from 15.93 to 2 wt% in 60 min. In the second stage, the transesterification process generated fatty acid methyl esters (FAMEs) with 99% efficiency was performed in 30 min with the optimal conditions as follows; a methanol-to-oil molar ratio of 6:1, 1 wt% KOH, at a temperature of 40 °C, and 20% (wt/wt) acetone as co-solvent. The produced biodiesel quality meets the standards JIS K2390 and EN 14214 regarding FAME yield, FFAs and water contents.


Assuntos
Biocombustíveis , Jatropha/química , Óleos de Plantas/química , Solventes/química , Esterificação , Ácidos Graxos não Esterificados/análise
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