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The decline in the population of Juniperus procera Hochast. ex Enal. in the woodlands of Saudi Arabia appears to be associated to their poor regeneration in the natural habitat. This study was conducted to investigate the presence and interaction of arbuscular mycorrhiza fungi (AMF) in the roots and heavy metals; cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), plumbum (Pb), uranium (U) and zinc (Zn) in the soil and roots of J. procera. Sampling was conducted in linear transaction, where a total of 120 individual trees were randomly selected. High values (59-79%) were recorded for root colonization with AMF in plant samples. Higher concentrations of Cd, Co, Cu, Pb, U and Zn in the soil and roots were found to be related to lower mycorrhiza infection, while Cr and Ni showed otherwise. In general, the concentration of heavy metal elements in the soil was significantly higher than that recorded in the roots of plant samples. AMF symbiosis probably affected heavy metal translocation from the soil into the roots. The presence of AMF and its relationship with heavy metals may give an insight into the dynamics of AMF infection in the plant. In addition, the roles played by AMF in the absorption of heavy metals in mycorrhizal plants are further discussed. [ABSTRACT FROM AUTHOR]

The chemical composition of the leaf oil of Piper maingayi isolated by hydrodistillation was analyzed by capillary GC and GC/MS. Forty-three components accounting for 91.2% of the oil were identified. Sesquiterpenes contributed the main composition (75%) with β-caryophyllene (39.6%) as the major constituent [ABSTRACT FROM AUTHOR]

The chemical composition of the rhizome oil of Kaempferia rotunda isolated by hydrodistillation was analyzed by capillary GC and GC/MS. The main constituents found in the oil were pentadecane (25.4%), bornyl acetate (24.9%), benzyl benzoate (15.3%) and camphor (12.1%). [ABSTRACT FROM AUTHOR]

Currently, Malaysia is one of the main producers of medium density fibreboard (MDF) in the Asia Pacific region. The adhesives used are mainly formaldehyde-based. These adhesives emit formaldehyde that pose a problem to the environment when the boards degrade. This study investigated the amount of extractable formaldehyde, effects of degraded medium density fibreboard on soil and the ability of fungi to degrade waste MDF. Medium density fibreboard of two thicknesses, 6 and 18 mm, were used. The extractable formaldehyde was determined in accordance with EN717-3:1996 E flask method. The unsterile soil burial and monoculture fungal tests were carried out in accordance with BS 1982: 1990. The monoculture fungi used were white rot fungi, Coriolus versicolor, Lentinus sajor-caju and Shizophyllum commune and brown rot fungus, Gloeophyllum trabeum. The amount of extractable formaldehyde was found to decrease with time. The weight loss of soil burial and monoculture samples were substantial. The degradation of waste MDF had affected the cation exchange capacity (CEC) of soils and the exchangeable cation content in the soil. The weight loss caused by L. sajor-caju was higher compared with that caused by C. versicolor, S. commune and G. trabeum. [ABSTRACT FROM AUTHOR]

Fine scale population structure of Malays - the major population in Malaysia, has not been well studied. This may have important implications for both evolutionary and medical studies. Here, we investigated the population sub-structure of Malay involving 431 samples collected from all states from peninsular Malaysia and Singapore. We identified two major clusters of individuals corresponding to the north and south peninsular Malaysia. On an even finer scale, the genetic coordinates of the geographical Malay populations are in correlation with the latitudes (R(2) = 0.3925; P = 0.029). This finding is further supported by the pairwise FST of Malay sub-populations, of which the north and south regions showed the highest differentiation (FST [North-south] = 0.0011). The collective findings therefore suggest that population sub-structure of Malays are more heterogenous than previously expected even within a small geographical region, possibly due to factors like different genetic origins, geographical isolation, could result in spurious association as demonstrated in our analysis. We suggest that cautions should be taken during the stage of study design or interpreting the association signals in disease mapping studies which are expected to be conducted in Malay population in the near future.

The essential oils obtained by hydrodistillation of the rhizomes of Alpinia aquatica Rosc. syn. Alpinia melanocarpa and Alpinia malaccensis Roscoe were analysed by capillary gas chromatography and gas chromatography-mass spectrometry. Eighteen compounds, representing 98.4% of the essential oil were identified in A. aquatica rhizome oil, with β-sesquiphellandrene in 36.5% being the major constituent, while 20 compounds representing 99.7% of the rhizome oil of A. malaccensis were identified, among which methyl (E)-cinnamate (78.2%) was the major constituent.

In this paper, we investigate the possibility of computing quantitatively accurate images of mass density variations in soft tissue. This is a challenging task, because density variations in soft tissue, such as the breast, can be very subtle. Beginning from an image of refraction angle created by either diffraction-enhanced imaging (DEI) or multiple-image radiography (MIR), we estimate the mass-density image using a constrained least squares (CLS) method. The CLS algorithm yields accurate density estimates while effectively suppressing noise. Our method improves on an analytical method proposed by Hasnah et al (2005 Med. Phys. 32 549-52), which can produce significant artefacts when even a modest level of noise is present. We present a quantitative evaluation study to determine the accuracy with which mass density can be determined in the presence of noise. Based on computer simulations, we find that the mass-density estimation error can be as low as a few per cent for typical density variations found in the breast. Example images computed from less-noisy real data are also shown to illustrate the feasibility of the technique. We anticipate that density imaging may have application in assessment of water content of cartilage resulting from osteoarthritis, in evaluation of bone density, and in mammographic interpretation.