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1.
Sci Rep ; 10(1): 18108, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33093604

RESUMO

In the present study black tea extract (BTE) solution which is familiar for drinking was used to prepare cerium metal-complexes (Ce(III)-complex). The prepared Ce(III)-complex was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-Vis spectroscopy. The results indicate that BTE solution is a novel green coordination chemistry approach for the synthesis of metal complexes. The outcomes signify that coordination occurs between cerium cations and polyphenols. The synthesis of metal-complexes with superior absorption performance in the visible region is a challenge for optoelectronic device applications. The suspended Ce(III)-complex in distilled water was mixed with poly (vinyl alcohol) (PVA) polymer to fabricate PVA/ Ce(III)-complex composites with controlled optical properties. The PVA/Ce(III)-complexes composite films were characterized by FTIR, XRD, and UV-Vis spectroscopy. The XRD findings confirms the amorphous structure for the synthesized Ce(III)-complexes. The addition of Ce(III)-complex into the PVA host polymer led to the growth of polymer composites with controllable small optical band gaps. It is shown by the FTIR spectra of the composite films that the functional groups of the host PVA have a vigorous interaction with the Ce(III)-complex. The XRD deconvolution on PVA composites reveals the amorphous phase enlargement with increasing Ce(III)-complex concentration. It is indicated in the atomic force microscopy (AFM) that the surface roughness in the doped PVA films increases with the increase of the Ce(III)-complex. There is a decrease in absorption edge from 5.7 to 1.7 eV. It becomes possible to recognize the type of electron transition by studying both the Tauc's model and optical dielectric loss (ɛi) parameter.

2.
Int J Mol Sci ; 20(16)2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31405255

RESUMO

The present work proposed a novel approach for transferring high-risk heavy metals tometal complexes via green chemistry remediation. The method of remediation of heavy metals developed in the present work is a great challenge for global environmental sciences and engineering because it is a totally environmentally friendly procedure in which black tea extract solution is used. The FTIR study indicates that black tea contains enough functional groups (OH and NH), polyphenols and conjugated double bonds. The synthesis of copper complex was confirmed by the UV-vis, XRD and FTIR spectroscopic studies. The XRD and FTIR analysis reveals the formation of complexation between Cu metal complexes and Poly (Vinyl Alcohol) (PVA) host matrix. The study of optical parameters indicates that PVA-based hybrids exhibit a small optical band gap, which is close to inorganic-based materials. It was noted that the absorption edge shifted to lower photon energy. When Cu metal complexes were added to PVA polymer, the refractive index was significantly tuned. The band gap shifts from 6.2 eV to 1.4 eV for PVA incorporated with 45 mL of Cu metal complexes. The nature of the electronic transition in hybrid materials was examined based on the Taucs model, while a close inspection of the optical dielectric loss was also performed in order to estimate the optical band gap. The obtained band gaps of the present work reveal that polymer hybrids with sufficient film-forming capability could be useful to overcome the drawbacks associated with conjugated polymers. Based on the XRD results and band gap values, the structure-property relationships were discussed in detail.


Assuntos
Complexos de Coordenação/química , Cobre/química , Polifenóis/química , Álcool de Polivinil/química , Chá/química , Química Verde/métodos , Extratos Vegetais/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
BMC Public Health ; 14 Suppl 2: S6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25080995

RESUMO

BACKGROUND: Malaysia faces burgeoning obesity and diabetes epidemics with a 250% and 88% increase respectively between 1996 and 2006. Identifying the health challenges of young adults in Malaysia, who constitute 27.5 % of the population, is critical for NCD prevention. The aim of the study was two-fold: (1) to achieve consensus amongst stakeholders on the most important challenge impacting the health of young adults, and (2) to engage with stakeholders to formulate a NCD prevention framework. METHODS: The Delphi Technique was utilised to achieve group consensus around the most important life and health challenges that young adults face in Malaysia. Subsequently, the results of the consensus component were shared with the stakeholders in an engagement workshop to obtain input on a NCD prevention framework. RESULTS: We found that life stress was a significant concern. It would seem that the apathy towards pursuing or maintaining a healthy lifestyle among young adults may be significantly influenced by the broader distal determinant of life stress. The high cost of living is suggested to be the main push factor for young working adults towards attaining better financial security to improve their livelihood. In turn, this leads to a more stressful lifestyle with less time to focus on healthier lifestyle choices. CONCLUSIONS: The findings highlight a pivotal barrier to healthier lifestyles. By assisting young adults to cope with daily living coupled with realistic opportunities to make healthier dietary choices, be more active, and less sedentary could assist in the development of NCD health promotion strategies.


Assuntos
Adaptação Psicológica , Doença Crônica/prevenção & controle , Características da Família , Comportamentos Relacionados com a Saúde , Estilo de Vida , Adulto , Consenso , Técnica Delphi , Dieta/psicologia , Feminino , Promoção da Saúde/organização & administração , Humanos , Malásia , Masculino , Atividade Motora , Comportamento Sedentário , Adulto Jovem
4.
Med J Malaysia ; 51(1): 129-30, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10967991

RESUMO

A total of 1131 Police Field Force personnel were screened serologically for schistosomiasis in Malaysia. A total of 150 (13.3%) were tested positive or borderline. Stool samples from 75 of these cases were however all negative for schistosome eggs. This survey suggests that Police Field Force personnel may be agents for propagating the schistosome life cycle in Malaysia.


Assuntos
Polícia , Esquistossomose/diagnóstico , Testes Sorológicos , Animais , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Humanos , Malásia , Schistosoma/isolamento & purificação
5.
J Trop Med Hyg ; 92(3): 203-8, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2738992

RESUMO

A stable population at risk of Malaysian schistosomiasis was studied. Census results indicated that approximately one-fourth of the inhabitants used a stream where Schistosoma malayensis-infected snails were present as their principal source of water for bathing, drinking, and household tasks. The general population also contacted this stream when fording it or while fishing. Serological surveys using enzyme-linked immunosorbent assay (ELISA) and the circumoval precipitin (COP) test revealed six (9%) and three (4%) positives, respectively, among 67 persons examined. No schistosome ova were found in a general survey of 56 persons which included five ELISA positive and two COP test positive patients. ELISA and COP test prevalences among those dependent on the foci of transmission for water, 13 and 7% respectively, were only slightly higher than prevalences among the remainder of the population, 8 and 4% respectively. These results indicate that even among a stable population at risk of Malaysian schistosomiasis the prevalence is low. Our findings support the hypothesis that S. malayensis is a zoonotic infection in man and that it is unlikely to become a significant public health problem.


Assuntos
Esquistossomose/epidemiologia , Abastecimento de Água , Adolescente , Adulto , Animais , Criança , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Testes de Precipitina , Valor Preditivo dos Testes , População Rural , Caramujos , Zoonoses
7.
Artigo em Inglês | MEDLINE | ID: mdl-6523170

RESUMO

Using ELISA and COPT diagnostic tests, serological evidence of Malaysian schistosomiasis was discovered among Orang Asli populations from three areas in Peninsular Malaysia. Serum samples collected in 1975 indicated an ELISA-positive prevalence of 25% and a COPT prevalence of 11% from Pos Iskandar, Pahang and an ELISA prevalence of 13% and a COPT of 4% from Bukit Lanjan, Selangor. Resurveys at these site in 1982-1984 showed a continued presence of serological positive individuals but prevalence rates were markedly lower: 7% and 1% for ELISA and 4% and 2% for COPT at Pos Iskandar and Bukit Lanjan respectively. Snail hosts were not found at either site. The source of infection for persons living in these lowland areas remains unknown. In a third area, Kuala Tahan, Pahang, located in the foothills of the central mountain range, foci of transmission have been found near to Orang Asli settlements. The serological prevalence rate among Negrito Orang Asli in that study area was 9% for ELISA and 4% for COPT. Thirty-three of 36 COPT-positive sera produced vacuolated bleb precipates and in 31 these were the only reactions seen. The high percentage of positives producing only these precipates suggests that among Orang Asli schistosomiasis patients such reactions are not an indication of recently acquired infection as has been reported for schistosomiasis patients in the Philippines.


Assuntos
Povo Asiático , Esquistossomose/epidemiologia , Adolescente , Adulto , Animais , Anticorpos/análise , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Humanos , Lactente , Recém-Nascido , Malásia , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Testes de Precipitina , Schistosoma/imunologia , Esquistossomose/diagnóstico , Esquistossomose/parasitologia , Caramujos/parasitologia
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