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1.
Bull Environ Contam Toxicol ; 95(6): 790-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26395356

RESUMO

Immobilisation of heavy metals in a 30-year old active scrap metal yard soil using three waste materials, namely coconut tree sawdust (CTS), sugarcane bagasse (SB) and eggshell (ES) was investigated. The contaminated soil was amended with amendments at application rates of 0 %, 1 % and 3 % (w/w). The effects of amendments on metal accumulation in water spinach (Ipomoea aquatica) and soil metal bioavailability were studied in a pot experiment. All amendments increased biomass yield and reduced metal accumulation in the plant shoots. The bioconcentration factor and translocation factor values of the metals were in the order of Zn > Cu > Pb. The addition of ES, an alternative source of calcium carbonate (CaCO3), has significantly increased soil pH and resulted in marked reduction in soil metal bioavailability. Therefore, CTS, SB and ES are promising low-cost immobilising agents to restore metal contaminated land.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Resíduos/análise , Animais , Biodegradação Ambiental , Disponibilidade Biológica , Biomassa , Cocos/química , Casca de Ovo/química , Ipomoea/metabolismo , Brotos de Planta/química , Saccharum/química , Poluentes do Solo/química , Zinco
2.
J Digit Imaging ; 28(4): 417-27, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25736857

RESUMO

This paper presents an automatic region of interest (ROI) segmentation method for application of watermarking in medical images. The advantage of using this scheme is that the proposed method is robust against different attacks such as median, Wiener, Gaussian, and sharpening filters. In other words, this technique can produce the same result for the ROI before and after these attacks. The proposed algorithm consists of three main parts; suggesting an automatic ROI detection system, evaluating the robustness of the proposed system against numerous attacks, and finally recommending an enhancement part to increase the strength of the composed system against different attacks. Results obtained from the proposed method demonstrated the promising performance of the method.


Assuntos
Segurança Computacional , Diagnóstico por Imagem , Heurística , Interpretação de Imagem Assistida por Computador , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Distribuição Normal
3.
J Biotechnol ; 184: 219-28, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-24910973

RESUMO

A Pichia pastoris transformant carrying the cutinase cDNA of Glomerella cingulata was over-expressed in a 5L bioreactor (2.0L working volume) under fed-batch conditions. Bioreactor experiments rely on varying selected parameters in repeated rounds of optimisation: here these included duration of induction, pH and temperature. Highest cell densities (320gL(-1) wet cell weight) with a cutinase production of 3800mgL(-1) and an activity of 434UmL(-1) were achieved 24h after induction with methanol in basal salt medium (at pH 5 and 28°C). Characterisation of the cutinase showed that it was stable between pH 6 and pH 11, had an optimum pH of 8.0 and retained activity for 30min at 50°C (optimum temperature 25°C).The preferred substrates of G. cingulata cutinase were the medium- to long-chain ρ-nitrophenyl esters of ρ-nitrophenylcaprylate (C8), ρ-nitrophenyllaurate (C12) and ρ-nitrophenylmyristate (C14), with the highest catalytic efficiency, kcat/Km of 7.7±0.7mM(-1)s(-1) for ρ-nitrophenylcaprylate. Microscopic analyses showed that the G. cingulata cutinase was also capable of depolymerising the high molecular weight synthetic polyester, polyethylene terephthalate.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Hidrolases de Éster Carboxílico/biossíntese , Phyllachorales/enzimologia , Proteínas Recombinantes/biossíntese , Reatores Biológicos , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Concentração de Íons de Hidrogênio , Phyllachorales/genética , Pichia/genética , Pichia/crescimento & desenvolvimento , Polietilenotereftalatos/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tensoativos/química , Temperatura
4.
J Digit Imaging ; 27(6): 714-29, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24871349

RESUMO

The ever-growing numbers of medical digital images and the need to share them among specialists and hospitals for better and more accurate diagnosis require that patients' privacy be protected. As a result of this, there is a need for medical image watermarking (MIW). However, MIW needs to be performed with special care for two reasons. Firstly, the watermarking procedure cannot compromise the quality of the image. Secondly, confidential patient information embedded within the image should be flawlessly retrievable without risk of error after image decompressing. Despite extensive research undertaken in this area, there is still no method available to fulfill all the requirements of MIW. This paper aims to provide a useful survey on watermarking and offer a clear perspective for interested researchers by analyzing the strengths and weaknesses of different existing methods.


Assuntos
Segurança Computacional/normas , Confidencialidade/normas , Coleta de Dados/métodos , Diagnóstico por Imagem/normas , Coleta de Dados/estatística & dados numéricos , Humanos
5.
Genet Mol Res ; 13(2): 2939-48, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24782128

RESUMO

The sympathetic nervous system plays a major role in blood pressure regulation. Beta 2 (ß2) adrenoceptor gene polymorphisms have been associated with hypertension in different populations with conflicting results. We examined the association of three common polymorphisms, Arg16Gly, Gln27Glu, and Thr164Ile, of the ß2 adrenoceptor gene in Malaysian hypertensive subjects. A total of 160 hypertensive and control subjects were recruited. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and anthropometric measurements were obtained from each subject. Biochemical analyses of lipid profiles were conducted with an autoanalyzer. DNA samples were extracted from blood and buccal cells. Genotyping was accomplished with polymerase chain reaction-restriction fragment length polymorphism. SBP, DBP, body mass index, and biochemical factors all differed significantly between case and control subjects (P < 0.05). The genotype frequencies of Arg16Arg, Arg16Gly, and Gly16Gly were 22.5, 70, and 7.5% among cases and 33.1, 63.1, and 3.8% among controls, respectively. The genotype frequencies of Gln27Gln, Gln27Glu, and Glu27Glu among cases were 41.1, 50, and 1.9% compared to 77.5, 20.6, and 1.9% among controls, respectively. In this study, the Gln27Glu polymorphism was significantly associated with Malaysian hypertensive subjects (P < 0.05). Therefore, the Gln27Glu polymorphism of the ß2 adrenoceptor could be a risk factor associated with hypertension among Malaysians.


Assuntos
Pressão Sanguínea/genética , Estudos de Associação Genética , Hipertensão/genética , Receptores Adrenérgicos beta 2/genética , Adulto , Povo Asiático , Feminino , Genótipo , Humanos , Hipertensão/patologia , Malásia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
6.
Comput Med Imaging Graph ; 35(3): 186-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21036539

RESUMO

This paper investigates a novel statistical discrimination procedure to detect PTB when the gold standard requirement is taken into consideration. Archived data were used to establish two groups of patients which are the control and test group. The control group was used to develop the statistical discrimination procedure using four vectors of wavelet coefficients as feature vectors for the detection of pulmonary tuberculosis (PTB), lung cancer (LC), and normal lung (NL). This discrimination procedure was investigated using the test group where the number of sputum positive and sputum negative cases that were correctly classified as PTB cases were noted. The proposed statistical discrimination method is able to detect PTB patients and LC with high true positive fraction. The method is also able to detect PTB patients that are sputum negative and therefore may be used as a complement to the gold standard.


Assuntos
Algoritmos , Interpretação Estatística de Dados , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Radiografia Torácica/métodos , Radiografia Torácica/normas , Tuberculose Pulmonar/diagnóstico por imagem , Humanos , Malásia , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Comput Med Imaging Graph ; 34(2): 160-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19758785

RESUMO

This paper presents a statistical method for the detection of lobar pneumonia when using digitized chest X-ray films. Each region of interest was represented by a vector of wavelet texture measures which is then multiplied by the orthogonal matrix Q(2). The first two elements of the transformed vectors were shown to have a bivariate normal distribution. Misclassification probabilities were estimated using probability ellipsoids and discriminant functions. The result of this study recommends the detection of pneumonia by constructing probability ellipsoids or discriminant function using maximum energy and maximum column sum energy texture measures where misclassification probabilities were less than 0.15.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Pneumonia/diagnóstico , Radiografia Torácica , Algoritmos , Análise Discriminante , Humanos , Análise de Componente Principal
8.
Planta Med ; 63(2): 193-4, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17252347
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