The effect of glufosinate ammonium in three different textured soil types under Malaysian tropical environment

Glufosinate ammonium is a broad spectrum, non-selective, contact and organophosphate herbicide which is commonly used in Malaysian oil palm plantations. Research area was one of the oil palm growing areas of Malaysia is located adjacent to the Tasik Chini, Pahang. Farmers use this herbicide to control several types of unwanted plants which could compete with the oil palm for nutrients. Rain water and the sprayed solution are easily adsorbed by soil particles. The glufosinate ammonium sorption was determined by the batch equilibrium technique. The collected soil samples (0-50 cm depth) divided into five groups at 10 cm depth intervals. Glufosinate ammonium adsorption coefficients were correlated with the soil pH, organic matter (OM), clay content, and cation exchange capacity (CEC). Series of glufosinate ammonium standard were as 0.01, 0.1, 0.25, 0.5, 1, 3, 5, and 10 μm/mL. The Linear and Freundlich equations were fitted for obtaining the adsorption and desorption isotherms. The result of the analyses showed that adsorption of glufosinate ammonium was correlated to the clay content. The clay fraction of the soil is the main absorbent of the glufosinate ammonium. Desorption from the soil was indicated by the high binding strength of the adsorbed glufosinate ammonium

Circulating adhesion molecules and arterial stiffness

Aim: VCAM-1 and ICAM-1 are two important members of the immunoglobulin gene superfamily of adhesion molecules, and their potential role as biomarkers of diagnosis, severity and prognosis of cardiovascular disease has been investigated in a number of clinical studies. The aim of the present study was to determine the relationship between circulating ICAM-1 and VCAM-1 levels and aortic stiffness in patients referred for echocardiographic examination. Methods: Aortic distensibility was determined by echocardiography using systolic and diastolic aortic diameters in 63 consecutive patients referred for echocardiography. Venous samples were collected in the morning after a 12-hour overnight fast, and serum concentrations of ICAM-1 and VCAM-1 were measured using commercial enzyme immunoassay kits. Results: Data of a total of 63 participants (mean age 55.6 ± 10.5 years, 31 male) were included in the study. Circulating levels of adhesion molecules were VCAM-1: 12.604 ± 3.904 ng/ml and ICAM-1: 45.417 ± 31.429 ng/ml. We were unable to demonstrate any correlation between indices of aortic stiffness and VCAM-1 and ICAM-1 levels. Conclusion: The role of soluble adhesion molecules in cardiovascular disease has not been fully established and clinical studies show inconsistent results. Our results indicate that levels of circulating adhesion molecules cannot be used as markers of aortic stiffness in patients

Dissipation of chlorpyrifos in a Malaysian agricultural soil: a comparison between a field experiment and simulation by the VARLEACH and PERSIST models

A comparison of the dissipation of chlorpyrifos in a Malaysian agricultural soil was undertaken using data from a field experiment and simulation by the PERSIST model. The study was carried out at an oil palm estate located close to the Kuala Lumpur International Airport (KLIA), Sepang, Selangor (for field experiment). The plots were treated with chlorpyrifos at the manufacturer’s recommended dosage. Soil samples were collected according to the sampling schedule at intervals of 0, 1, 3, 7, 14, 21, 30, 60 and 90 days. Residues of chlorpyrifos in soil from the field trial were analyzed in the laboratory. Simulation of chlorpyrifos leaching and persistency was done using two computer-run software VARLEACH and PERSIST. Generally, predicted data for chlorpyrifos residue obtained using the VARLEACH and PERSIST models was found to be well matched with the observed data from the field trial. The PERSIST Prediction for chlorpyrifos residue in soils planted with oil palm trees was found to be accurate and conformed to the results observed in the field trial

Persistence of carbofuran in Malaysian waters

The stability of carbofuran was investigated in river, sea and ground waters of Malaysia. The water samples collected were from pollution-free areas in Malaysia and all samples were spiked with carbofuran at 1 μg/mL. The concentrations of carbofuran residue in the samples were measured under light and dark conditions at various intervals and their half-lives determined. It was found that the half-lives in unfiltered and filtered river water exposed to sunlight and filtered river water kept in the dark were 5, 6.6 and 8.6 days respectively. For sea water exposed to sunlight and kept in the dark, the half-lives of carbofuran were 3.28 and 12.98 days respectively. The residue of carbofuran was monitored in ground water and it was observed that the concentration of carbofuran was reduced to 65% of the initial concentration after 67 days. It was observed that the dissipation of carbofuran through oxidation and adsorption on solid suspended materials was insignificant. This study showed that photolysis and hydrolysis are the main pathways for the dissipation of carbofuran in water and that the pH of the water is one of the main factors influencing its degradation

Allelopathic potential of the leaf and seed of Pueraria javanica Benth. on the germination and growth of three selected weed species

Pueraria javanica Benth. is one of the most common leguminous cover crop used in oil palm plantations of Malaysia. A study was conducted to determine the allelopathic potential of this plant, using the aqueous extract, sandwich and dish-pack methods, with the seed and leaf (of P. javanica) on three bioassay weed species namely, Eleusine indica, Cyperus iria and Chromolaena odorata. The aqueous extract experiment was conducted using 0 (control), 16.7, 33.3 and 66.7 g/L of the aqueous leaf and seed extracts while the sandwich method was carried out using 10 and 50 mg of each of the donour plant parts. Meanwhile, the dish-pack method was done using four different distances (41, 58, 82 and 92 mm) away from the donour plant. All experiments were replicated five times using the complete randomized design (CRD). The leaf extract exhibited 100% reduction on the fresh weight of E. indica and C. odorata while the seed extract exhibited 100% reduction on all parameters for E. indica and on the fresh weight of C. iria at 66.7 g/L concentration. The seed and leaf at 10 and 50 mg significantly reduced the radicle length of all the bioassay species. The dish-pack experiment also showed a reduction effect on the germination percentage and seedling growth parameters of all the bioassay species. However, the reduction effect was not totally in accordance to the distance from the donor species. More studies need to be conducted to determine the type of reduction mechanism involved in the allelopathic activity especially with respect to molecular and biochemical aspects

Effect of gibberellic acid on the growth and yield of groundnut (Arachis hypogaea L.)

This study was conducted during two different seasons to determine the best concentration of gibberellic acid (GA3) that could result in better growth and higher yield of groundnut (Arachis hypogaea L.). Experiments were conducted during the 2015 dry season and 2016 wet season at the field of the Universiti Kebangsaan Malaysia (UKM), Bangi, Selangor, Malaysia. The purpose of the experiments was to investigate the response of the groundnut plants to four levels of GA3 (0, 50, 100 and 150 mg L−1) as foliar spray at 21 and 42 days after sowing. The treatments were laid out in a randomized complete block design and replicated thrice. The results showed that the treatment of 150 mg L−1 GA3 significantly (p<0.05) increased plant height, number of branches per plant, total dry weight, number of pods per plant, pod yield, 100 seed weight, % shelling, oil content, protein content, seed moisture and germination percentage during the wet and dry seasons. In conclusion, the 150 mg L−1 GA3 concentration is the optimum level required to enhance the growth and yield in groundnuts during the wet and dry seasons

Taxonomic value of leaf venation and trichome characteristics in some Byttneria L. and Pterocymbium R. Br. (Malvaceae S.L)

A study on some leaf anatomical characteristics was undertaken on two genera in Malvaceae s.l namely Byttneria L. and Pterocymbium R. Br. The objective was to determine the taxonomic value of leaf venation characteristics especially in identification and classification of species. In the study, five species were chosen, three Byttneria species, namely B. curtisii,B. jackiana, B. maingayi, and two Pterocymbium species, namely P. tinctorium and P. tubulatum. Byttneria and Pterocymbium have been split into two subfamilies, Byttneroideae and Sterculoideae, of Malvaceae s.l respectively. Leaf clearing, staining, mounting and observation under a light microscope were techniques used for the study. Results showed that the similarities and differences in leaf venation could be useful in classification and identification of species. The common characteristics found in all species studied were the presence of entire marginal venation and closed system venation with minimum free ending veinlets in the areolar venation. The variations in the leaf venation can be used to distinguish species, which are complete ultimate marginal venation in B. curtisii and B. maingayi; curved to looped pattern and incomplete, ultimate marginal venation in B. jackiana, P. tubulatum and P. tinctorium. The presence of simple unicellular trichomes in B. jackiana and two types of trichomes (simple unicellular trichomes and multicellular glandular trichomes) and crystals alongside veinlets in P. tubulatum can also be used to further identify these two species from other species studied. Therefore, the study showed that leaf anatomical characteristics in Byttneria and Pterocymbium can be used in species identification and have taxonomic value

ANALISIS DAN PERANCANGAN SISTEM INFORMASI TENDER AREA KOMERSIAL PADA PT. ANGKASA PURA I (PERSERO) STUDI KASUS BANDARA SEPINGGAN BALIKAPAN

Area yang digunakan untuk mengelola proses komersialisasi dalam pengisian ruangan disebut sebagai area komersial. PT. Angkasa Pura I (Persero) menerapkan proses tender dalam pengelolaan area komersial berdasarkan Commercial Space Plan yang telah disepakati. Banyaknya ruang kosong di Area komersial di BandaraSepinggan Balikpapan menyebabkan tidak maksimalnya pemanfaatan area komersial di area Bandara sehingga tidak maksimalnya pendapatan perusahaan yang didapatkan dari pemanfaatan area komersial.Berdasarkan permasalahan tersebut, tujuan penelitian ialah mengetahui komponen Sistem Informasi Tender Area Komersial dan mengetahui Perancangan Sistem Informasi Tender Area Komersialdi PT. Angkasa Pura I (Persero) Bandara Sepinggan Balikpapan. Perancangan menggunakan metode Object Oriented Analysis and Design (OOAD) sedangkan analisis dilakukan pada proses bisnis yang sedang berjalan yang selanjutnya hasil analisis dituangkan dalam perancangan sistem informasi Tender Area Komersial berupa aplikasi web yang dapat membantu kegiatan pelaksaan tender. Sistem informasi Tender Area Komersial ini memudahkan bagi PT. Angkasa Pura I (Persero) dan calon mitra usaha dalam memberikaninformasi tender yang sedang berjalan dari mulai pendaftaran, pemilihan paket tender, pengumpulan dokumen dan pengumuman hasil tender

Evaluation of the effect of Sidoarjo mud on aquatic life using chromatophores and the microstructure of fish scales

The Sidoarjo mud is the first visible phenomenon of a mud volcano that occurs in a human settlement and which is subsequently channelled into a river. Clay, aluminium and iron were reported to be the dominant contaminants that could possibly come into contact with and accumulate on the surface of local fish and initiate alteration in scale microstructure. The aim of this study was to evaluate the extent of water body contamination in the Sidoarjo mud by evaluating the chromatophore density and microstructure deformation of fish scales that act as biomarkers. Scale samples were obtained from caged Mozambique tilapia (Oreochromis mossambicus) fish that were placed downstream and upstream of the Sidoarjo mud spillway pipes. With respect to melanophore density, it was found that the scales of fish exposed in the downstream section were significantly lower in chromatophores (100 chr/mm²). This study suggested that the density of chromatophores was closely related to the concentration of total suspended solids (r = 0.69), which was possibly enhanced by iron (r = 0.56). Using scanning electron microscopy analysis, some deformation, i.e. irregularity of spherule shape and increasing pits in the space between ridges, were observed

Modelling for determination of fe uptake by Brassica chinensis Jusl var. parachinensis (Bailey) Tsen & Lee (Flowering White Cabbage)

The study was conducted to determine the best model suitable for the determination of ferrum uptake in Brassica chinensis (flowering white cabbage). A nonlinear regression model was selected to determine the amount of ferrum absorbed by each part of the Brassica chinensis plant namely the leaves, stems and roots. The Levenberg-Marquardt method was used to perform the nonlinear least square fit. This method employs information on the gradients and hence requires specification of the partial derivatives. A suitable model was obtained from the exponential regression model. The polynomial model was found to be appropriate for leaves, the mono-exponential model was suitable for stems and the simple exponential model for roots. The residual plots and the normal probability plots from each of the models indicated no substantial diagnostic problems, so it can be concluded that the polynomial and exponential regression models provide adequate fit to determine data on heavy metal uptake by the flowering white cabbage