Browse publications by year: 2007

  1. Jain AK, Jain S, Rana AC
    Malays J Med Sci, 2007 Jan;14(1):10-7.
    PMID: 22593646
    The clinical application of new antineoplastic drugs has been limited because of low therapeutic index and lack of efficacy in humans. Thus, improvement in efficacy of old and new anticancer drugs has been attempted by manipulating their pharmacokinetic properties. Four inter-related factors, which determine the pharmacokinetic behavior of a drug include absorption, distribution, metabolism and excretion. The drug-metabolizing enzymes have been classified in two major groups: phase I and phase II enzymes. Phase I enzymes comprise the oxidases, dehydrogenases, deaminases, hydrolases. Phase II enzymes include primarily UDP-glucuronosyltransferases (UGTs), glutathionetransferases (GSTs), sulfotransferases (SULTs), N-acetyl transferases (NATs), methyltransferases and aminoacid transferases that conjugate products of phase I reactions and parent compounds with appropriate functional groups to generate more water soluble compounds which are more readily eliminated. The importance of these enzymes in the metabolism of specific drugs varies according to the chemical nature of the drug, Drug metabolism is modulated by factors that change among species and even among individuals in a population. Such factors can be environmental or genetic in origin, and influence how a drug is metabolized and to what extent. An awareness of these variables is invaluable when the safety and efficacy of new anticancer drugs are evaluated (1).
  2. Yeang HY
    New Phytol, 2007;176(4):730-5.
    PMID: 17997756
    MeSH terms: Demography; Sunlight*; Tropical Climate; Signal Transduction/radiation effects; Hevea/physiology*; Hevea/radiation effects*; Flowers/physiology*; Flowers/radiation effects*
  3. ISBN: 978-983-3433-48-3
    Citation: Guidelines on Management of Health Care Workers (HCW) Infected with Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV). Putralaya: Ministry of Health, Malaysia; 2007

    Keywords: CPG
    MeSH terms: Discrimination (Psychology); Employment; Health Personnel; Hepatitis B; Hepatitis C; Humans; Infection; Malaysia; HIV Infections; Guidelines as Topic
  4. ISBN: 978-983-3433-47-6
    Citation: Guidelines on occupational exposures to human immunodeficiency virus (HIV), Hepatitis B virus (HBV) and Hepatitis C virus, and recommendations for post exposure prophylaxis (PEP). Putrajaya: Ministry of Health, Malaysia; 2007
    MeSH terms: Health Personnel; Hepatitis B; Hepatitis C; Humans; Malaysia; HIV Infections; Occupational Health; Guidelines as Topic; Post-Exposure Prophylaxis
  5. Groth I, Tan GYA, González JM, Laiz L, Carlsohn MR, Schütze B, et al.
    Int J Syst Evol Microbiol, 2007 Mar;57(Pt 3):513-519.
    PMID: 17329776 DOI: 10.1099/ijs.0.64602-0
    The taxonomic status of two actinomycetes isolated from the wall of a hypogean Roman catacomb was established based on a polyphasic investigation. The organisms were found to have chemical and morphological markers typical of members of the genus Amycolatopsis. They also shared a range of chemical, molecular and phenotypic markers which served to separate them from representatives of recognized Amycolatopsis species. The new isolates formed a branch in the Amycolatopsis 16S rRNA gene sequence tree with Amycolatopsis minnesotensis NRRL B-24435(T), but this association was not supported by a particularly high bootstrap value or by the product of the maximum-parsimony tree-making algorithm. The organisms were distinguished readily from closely related Amycolatopsis species based on a combination of phenotypic properties and from all Amycolatopsis strains by their characteristic menaquinone profiles, in which tetra-hydrogenated menaquinones with 11 isoprene units predominated. The combined genotypic and phenotypic data indicate that the isolates merit recognition as representing a novel species of the genus Amycolatopsis. The name proposed for this novel species is Amycolatopsis nigrescens sp. nov., with type strain CSC17Ta-90(T) (=HKI 0330(T)=DSM 44992(T)=NRRL B-24473(T)).
    MeSH terms: Actinomycetales/classification*; Actinomycetales/genetics; Actinomycetales/isolation & purification; Burial; DNA, Bacterial/genetics; DNA, Ribosomal/genetics; Genotype; Humans; Molecular Sequence Data; Phenotype; Phylogeny; RNA, Ribosomal, 16S/genetics; Roman World
  6. Carlsohn MR, Groth I, Tan GYA, Schütze B, Saluz HP, Munder T, et al.
    Int J Syst Evol Microbiol, 2007 Jul;57(Pt 7):1640-1646.
    PMID: 17625209 DOI: 10.1099/ijs.0.64903-0
    Three actinomycetes isolated from the surfaces of rocks in a medieval slate mine were examined in a polyphasic taxonomic study. Chemotaxonomic and morphological characteristics of the isolates were typical of strains of the genus Amycolatopsis. The isolates had identical 16S rRNA gene sequences and formed a distinct phyletic line towards the periphery of the Amycolatopsis mediterranei clade, being most closely related to Amycolatopsis rifamycinica. The organisms shared a wide range of genotypic and phenotypic markers that distinguished them from their closest phylogenetic neighbours. On the basis of these results, a novel species, Amycolatopsis saalfeldensis sp. nov., is proposed. The type strain is HKI 0457(T) (=DSM 44993(T)=NRRL B-24474(T)).
    MeSH terms: DNA, Bacterial/genetics; DNA, Bacterial/chemistry; DNA, Ribosomal/genetics; DNA, Ribosomal/chemistry; Fatty Acids/analysis; Genotype; Germany; Molecular Sequence Data; Phylogeny; Quinones/analysis; RNA, Bacterial/genetics; RNA, Ribosomal, 16S/genetics; Sequence Homology, Nucleic Acid; Soil Microbiology*; Bacterial Typing Techniques; Cluster Analysis; Polymerase Chain Reaction/methods; DNA Fingerprinting; Sequence Analysis, DNA; Genes, rRNA; Actinobacteria/classification*; Actinobacteria/genetics; Actinobacteria/isolation & purification*; Actinobacteria/chemistry
  7. Khatoon R, Khoo EM
    Asia Pac Fam Med, 2007;6(1).
    Aims: To determine whether the Edinburgh Claudication Questionnaire (ECQ) can be used as a screening tool for detecting peripheral arterial disease in patients with diabetes mellitus. 
    Methods: A cross-sectional study of 200 patients with diabetes over 18 years of age who attended a primary care clinic at a teaching hospital in Kuala Lumpur, Malaysia. Face-to-face interviews were conducted using the ECQ for the presence of intermittent claudication. Blood pressure and peripheral neuropathy were assessed. Ankle brachial pressure index (ABPI) was measured and used as a gold standard for the diagnosis of eripheral arterial disease (PAD), which was defined as an ABPI of < 0.9 on either leg. 
    Results: The overall prevalence of PAD was found to be 16% among patients with diabetes based on ABPI. Among these 32 patients with PAD, eight (25%) had symptoms of intermittent claudication based on the ECQ. The ECQ was found to have a low sensitivity (25%) but a high specificity (99.4%), with a positive predictive value of 88.9% and a negative predictive value of 88% for diagnosing PAD in patients with diabetes. 
    Conclusions: The ECQ is not a good screening tool for detection of PAD among patients with diabetes due to its low sensitivity. Key words: ankle brachial pressure, diabetes mellitus, Edinburgh Claudication Questionnaires, intermittent claudication, peripheral arterial disease.
    MeSH terms: Adult; Ambulatory Care Facilities; Blood Pressure; Cross-Sectional Studies; Diabetes Mellitus; Diagnosis; Hospitals, University; Humans; Malaysia; Mass Screening; Outpatients; Primary Health Care; Sensitivity and Specificity; Prevalence; Peripheral Vascular Diseases; Ankle Brachial Index
  8. Lee PY, Abang Taha AB, Lin K, Ghazali SR, Syed Ahmad Al-Mashoor SH
    Asia Pac Fam Med, 2007;6(1).
    Aims: To evaluate the utilization of complementary and alternative medicine (CAM) in Kuching, Sarawak, Malaysia Methods: This was a cross-sectional study of patients who attended three randomly selected primary care clinics over 4 months from January to April 2004. Results: A total of 198 patients were recruited. One hundred and eighty-one (91.4%) patients agreed to participate by answering the anonymous questionnaire. Results: Ninety (51.4%) patients used CAM of which 43 (47.8%) patients used more than one type of CAM. Utilization rates of CAM were found to be associated with employment status but not with other socio-demographic factors. The common types of alternative medicine used were massage (n = 63; 36.2%) and herbal medicine (n = 44; 25.1%). Forty-two (46%) of the CAM users, used CAM for the problems that led to their current clinic visit. Thirty-four (37.8%) were using alternative and modern medicine at the same time. The reasons for CAM usage given by about half of the patients were that CAM was more effective and better for emotional or mental health problems. Conclusions: Usage of CAM was common in patients who visited primary care clinics. It is important to recognize this fact as combined use of CAM can create potentially dangerous interactions with pharmacotherapies Key words: complementary and alternative medicine (CAM), primary care
    MeSH terms: Complementary Therapies; Ambulatory Care Facilities; Cross-Sectional Studies; Humans; Malaysia; Massage; Outpatients; Primary Health Care; Herbal Medicine
  9. Sivapathasundharam B, Einstein A, Syed RI
    Indian J Dent Res, 2007 10 17;18(4):218-21.
    PMID: 17938502
    In the recent World Health Organization classification of odontogenic tumours, desmoplastic ameloblastoma has been characterized as a variant of ameloblastoma, with specific clinical, radiographical, and histological features. Till date, 145 cases have been reported in Japanese, Chinese, Malaysian, Western, and African populations, with very few cases described in Indians. Here, we report five cases in the Indian population. The male to female ratio was 3:2. The mean age at diagnosis was 33.2 years. Four of the tumours were located in the maxilla, in the anterior premolar region. The lone mandibular tumour was located anteriorly, crossing the midline. Three of the tumours had a mixed radiologic appearance with poorly defined borders. Unilocular change was seen in one of them. Two tumours presented as unilocular radiolucencies with specks of radiopacities and well-circumscribed borders. Histologically, irregular odontogenic islands, with a stretched-out 'kite-tail' appearance, were seen in a dense desmoplastic stroma. The peripheral layer of the epithelial islands was made up of flattened cells and the inner core was made up of spindle-shaped and, in some instances, squamous-shaped cells. In two cases, odontogenic epithelium in the form of follicles, typical of solid/multicystic ameloblastoma, was seen and these were typed as 'hybrid' variants. All the cases were treated by resection.
    MeSH terms: Adult; Ameloblastoma/diagnosis*; Ameloblastoma/pathology; Epithelial Cells/pathology; Female; Humans; Male; Mandibular Neoplasms/diagnosis*; Mandibular Neoplasms/pathology; Maxillary Neoplasms/diagnosis*; Maxillary Neoplasms/pathology; Radiography
  10. Lee JK, Amir Sharifuddin MK
    DOI: 10.1111/j.1479-8077.2007.00314.x
    Aims: Hip fracture is frequently studied to reflect osteoporosis related fractures. The aim of this study was to look at ethnic differences in the incidence of hip fractures between the three races in Malaysia. Methods: This was a retrospective study performed for the years 1996 and 1997. Data from hospitals treating hip fractures in elderly patients were collected throughout the whole country. Result: The overall incidence of hip fractures was 90 per 100 000 individuals. Sixty-three percent of patients presenting with hip fractures were Chinese. This was followed by Malays at 20% and Indians, 13%. Race-specific incidence data showed that the fracture rates are highest among the Chinese (160 per 100 000) followed by Indians (150 per 100 000) and Malays (30 per 100 000). Females were twice as commonly affected compared to males. Race and sex-specific incidence data showed that the incidence was highest among Chinese females (220 per 100 000), followed by Indian females (200 per 100 000). The age-specific incidence was 500 per 100 000 for patients above 75 years, compared to 10 per 100 000 in those between 50 and 54 years. Conclusion: Hip fractures arecommon in Malaysia. There are differences in hip fracture incidence depending upon ethnicity. © 2007 Asia Pacific League of Associations for Rheumatology.
    MeSH terms: Aged; Ethnic Groups; Female; Hip Fractures; Hospitals; Malaysia; Male; Osteoporosis; Retrospective Studies; Incidence
  11. Mohd Shahrir MS, Abdul Halim AG, Soehardy Z, Kong NCT
    APLAR Journal of Rheumatology, 2007;10(2):112-116.
    DOI: 10.1111/j.1479-8077.2007.00270.x
    Background and method: This clinical experience involved the treatment of resistant systemic lupus erythematosus (SLE) patients with CD20 monoclonal antibody. Five patients failed conventional therapy, two developed complications and one needed rituximab as an emergency measure. Four patients had lupus nephritis, three had autoimmune hemolytic anemia, two had immune thrombocytopenia and one had lupoid hepatitis. The patients were aged 14-49 years, (mean 28.63). Three were Malays, two Chinese, two Indian and one Turkish; six were females. Mean disease duration was 63.25 months and mean total rituximab dose received was 2812.50 mL. Results: Hemoglobin levels improved from 9.3 ± 5.7 to 13.1 ± 8.6 g/dL for two SLE patients with autoimmune hemolytic anemia after 34 weeks (P = 0.180). Platelet counts improved from 25 ± 17 to 198 ± 97 × 10 9/high powered field from 0 to 10 weeks for three SLE patients with immune thrombocytopenia (P = 0.109). In the lupus nephritis patients on rituximab, serum albumin improved from 24.5 ± 23.2 to 37.5 ± 31.8 mmol/L (n = 3) from week 0 to week 17 (P = 0.100). Urine protein creatinine ratio improved from 0.55 ± 0.23 to 0.08 ± 0.03 g/mmol creatinine (P = 0.068) from week 0 to week 13. C3 and C4 improved from 90.8 ± 36.5 to 120.7 ± 37.9 (P = 0.07) and 21.6 ± 10.1-27.3 ± 16.2 mg/dL (P = 0.27), respectively, and Systemic Lupus Erythematosus Activity Disease Index was reduced from 17.9 ± 11.2 to 6.3 ± 6.8 (P = 0.375) after 8 weeks. Two patients developed drug reactions to rituximab. Conclusion: All of the patients responded to rituximab on top of their conventional therapy. © 2007 Asia Pacific League of Associations for Rheumatology and Blackwell Publishing Asia Pty Ltd.
    MeSH terms: Rituximab; Adolescent; Adult; Azathioprine; Chlorpheniramine; Creatinine; Diabetes Mellitus; Drug Hypersensitivity; Female; Hepatitis C; Humans; Hypertension; Lupus Erythematosus, Systemic*; Lupus Nephritis; Malaysia; Male; Methylprednisolone; Uric Acid
  12. Veerapen KK
    APLAR Journal of Rheumatology, 2007;10(4):287-294.
    DOI: 10.1111/j.1479-8077.2007.00308.x
    Objective: To profile the pattern of psoriatic arthritis (PsA) and its relationship to disease duration. Methods: Forty-six consecutive patients with PsA were entered into a cross-sectional study. Demographic data, disease duration and disability were recorded. Joint involvement was documented at 6 months from onset and at presentation. X-rays of the sacroiliac (SI) joints, thoracolumbar spine, and hands were taken. HLA B27 typing was done. Results: The male: Female ratio was 2.3: 1, mean age at onset of arthritis was 35.8 years and mean duration of PsA was 4.2 years. Oligoarticular involvement predominated (63%) at onset. Progression from oligoarthritis to polyarthritis occurred largely in the second year; 65.2% reported asymmetrical disease at onset while 50% had asymmetrical disease when disease duration was >.1 year. The frequency of involvement at onset was as follows: Sausage toes, metatarsophalangeals (MTPs) and interphalangeals (IPs) in 50% (each), proximal interphelangeals (PIPs) in 47.8%, sausage fingers 34.7% and knees 30%. With mean duration of 4.2 years it was: Sausage toe 71.1%, IP 69.5%, PIP and MTP 63%, knees 60.8%, distal interphalangeals (DIPs) 54.3%, sausage finger 52.1%, wrist 47.8%, followed by neck and back pain. Disability related to lower limb functions predominated and occurred early. Forty-one percent had radiological sacroiliatis/spondylitis and 46% had erosive arthritis in the hands; 10.2% were HLA B27 positive. Conclusion: PsA was progressive, starting predominantly as an asymmetrical oligoarthritis and becoming largely polyarticular within 2 years from onset. Lower limb disability was evident early and erosive changes in hand X-rays were seen in more than half the patients after 1 year. © 2007 Asia Pacific League of Associations for Rheumatology.
    MeSH terms: Back Pain; British Columbia; Cross-Sectional Studies; Female; Humans; Malaysia; Male; Pain; Arthritis, Psoriatic*; HLA-B27 Antigen
  13. Mohd Shahrir MS, Eashwary M, Heselynn H, Mohd Shahdan S
    DOI: 10.1111/j.1479-8077.2007.00252.x
    Aim: To provide the first case series analysis for psoriatic arthritis (PsA) in Malaysia.
    Methods: Patient records were studied from rheumatology clinics in Universiti Kebangsaan Malaysia Hospital and Putrajaya Hospital in Malaysia.
    Results: Thirty-one patients from two rheumatology centres were studied. Thirteen patients (41.9%) were male and 18 patients (58.1%) were female. Nineteen patients (61.3%) were Malays, four (12.9%) were Chinese, seven (22.6%) were Indians and one (3.2%) was a Sikh. The majority of patients were in the >.50 years age-group (11 [35.5%]) followed by the 41-50 years age-group (10 [32.3%]). Thirteen patients (41.9%) had the disease since 41-50 years of age. Twenty-three patients (77.4%) had no family history of PsA. Twenty-three patients (74.2%) had psoriasis first, seven (22.6%) had arthritis first and one (3.2%) developed psoriasis and arthritis at the same time. Twenty-four patients (77.4%) had positive activity correlation for skin and arthritis. The majority of patients had symmetrical arthritis (20 [64.5%]) and chronic plaque-like lesions (22 [71.0%]). These patients were on NSAIDS and methotrexate (14 [45.2%]). One patient (3.6%) needed surgery for joint replacement.
    Conclusion: Patients who were diagnosed as having PsA were Malays, age group of more than 50, disease onset at 41-50 years of age, no family history, had symmetrical and chronic plaque lesions, had psoriasis first and needed NSAIDS and methotrexate.
    MeSH terms: Anti-Inflammatory Agents, Non-Steroidal; Arthritis; China/ethnology; Female; Hospitals; Hospitals, University; Humans; India/ethnology; Malaysia; Malaysia/ethnology; Male; Methotrexate; Outpatient Clinics, Hospital; Outpatients; Psoriasis; Arthritis, Psoriatic*
  14. Leong KC, Teng CL
    Aust Fam Physician, 2007 Sep;36(9):679; author reply 680.
    PMID: 17918303
    Comment on: Cannon B, Usherwood TP. General practice consultations - how well do doctors
    predict patient satisfaction? Aust Fam Physician. 2007 Mar;36(3):185-6, 192. PubMed PMID: 17339988. https://www.racgp.org.au/afp/200703/15394
    MeSH terms: Attitude of Health Personnel; Family Practice/standards*; Humans; Physician-Patient Relations*; Physicians, Family/psychology*; Time Factors; Patient Satisfaction*; Health Care Surveys
  15. Kim SL, Wickneswari R, Chee YC
    Sains Malaysiana, 2007;36:233-242.
    The disturbance level of two nearby logged stands, Compartment 118 and Compartment 69 were studied in Ulu Sedili Forest Reserve, Johor. The mean basal area for trees (trees ³ 1 cm dbh) in logged stand of Compartment 118 showed 51% reduction in comparison to immediately before logging of the same stand. A similar level of reduction (47%) was observed for mean density of trees in Compartment 118. However, the mean basal area and mean density of tree were higher in 50-year logged Compartment 69 (21% and 122% respectively) compared to Compartment 118 before logging. Concurrently, we examined the effects of logging on genetic diversity of seedling, sapling and mature trees of two important timber species, Koompassia malaccensis and Dryobalanops aromatica using M13 universal primer (multilocus minisatellite DNA) and three other universally-primed primers. Mature trees of K. malaccensis showed 39% reduction in Shannon diversity index (H) in Compartment 69 compared to Compartment 118 before logging detected by M13 universal primer. This may be attributed to the small sample size of the species in Compartment 69. Reduction in H and polymorphic loci (P) for K. malaccensis was higher in seedlings, 5% and 56% respectively in Compartment 69 compared to mature trees (3% and 23% respectively). Contrastingly for seedlings and saplings of D. aromatica, increment in H was higher in Compartment 69 than Compartment 118 immediately after logging, which was 25% and 14% for seedlings while 21% and 14% for saplings, detected by M13 universal primer. The increased genetic diversity detected for this species may be due to its high density in Compartment 118 and Compartment 69. Loss in alleles caused a decline in H of K. malaccensis, especially mature trees in Compartment 69. On the other hand, H of D. aromatica was not affected by loss of alleles.
  16. Darwis S, Isnani, Ashat A
    Sains Malaysiana, 2007;36:207-211.
    The aim of semivariogram modeling is to infer the structure of spatial continuity of the measurements. Practical experiences show that semivariogram modeling is an important step in spatial interpolation. The usual empirical semivariogram is sensitive to extreme data and shows a noised pattern. Some robust empirical semivariogram was proposed. This paper reports the application of pairwise relative empirical semivariogram to Kamojang geothermal decline rate. Using the same data, the usual empirical semivariogram and pairwise semivariogram are compared. Comparative study shows that the empirical pairwise relative semivariogram is able to infer the structure of spatial continuity of the process.
    MeSH terms: Hypersensitivity; Spatial Analysis
  17. Roslinda Shamsudin, Abdul Razak Daud, Muhammad Azmi Abdul Hamid, Saiful Rizam Shamsudin
    Sains Malaysiana, 2007;36:195-200.
    Nitridation behaviour of Al-Mg-Si alloys was studied as a function of temperature by means of thermogravimetry method. A reactive gas, N2-4%H2 at a rate of 10 ml/min was purged into the thermogravimetry analyser chamber. The Al alloys were heated from 25oC to 625oC at the heating rate of 15oC/min and then reduced to 3oC/min until it reached 1500oC. It was found that by varying the amount of Mg and Si in Al-Mg-Si alloys significantly influenced the growth of the composites. A differential thermogravimetric curve shows the Mg containing alloys experienced many steps of chemical reactions. This indicates that besides AlN presence as a major phase, other compounds also exist in the final product. The X-ray diffraction results confirmed the existence of oxide phases such as a-Al2O3, MgAl2O4 and MgO in addition to residual Si and Al metal. The presence of oxide compounds is believed to be due to the reaction between the alloying elements and residual oxygen gas left in the reaction atmosphere. It was also found that Si could play a role in promoting the weight gain of the composite produced. The heating rate has also a profound effect on the weight gain, whereby higher heating rate resulted in low yielded of AlN during the nitridation reaction of the Al-Mg-Si alloys.
    MeSH terms: Alloys; Aluminum Oxide; Hot Temperature; Heating; Magnesium Oxide; Oxides; Oxygen; Temperature; Thermogravimetry; X-Ray Diffraction; Weight Gain
  18. Tangang FT, Mohd Syamil Mohd Yussof, Liew J
    Sains Malaysiana, 2007;36:165-173.
    The current circulation pattern in waters around Pulau Tinggi, Johor was deduced based on the results of the Acoustic Doppler Current Profiler (ADCP) measurements during a period of 16 – 19 August 2004. It appears that the currents, regardless of tidal cycle, were predominantly southerly or southeasterly with average speeds of between 30 – 50 cm s-1. There appears to be current speed horizontal gradient toward the island as the current became weaker as it gets closer to the island. In the upper 10-15 m the currents were slowed by the prevailing winds which were predominantly southeasterly during the period. In the lower layer, about 10 m from seabed, the current speed reduced drastically due to bottom friction. The circulation pattern proves to be a typical pattern of a flow around an island where an evident of an eddy was captured in the observation data in a station located south of the island. Estimated shallow water Reynolds number indicates that the flow may produce a pair vortex of opposite direction and a central return flow at the southern end of the island.
  19. Abdul Rahim Samsudin, Umar Hamzah, Zuraidah Ramli
    Sains Malaysiana, 2007;36:159-163.
    An integrated geophysical study was conducted to investigate the subsurface regional structure and the presence of a Quaternary sedimentary basin in the Olak Lempit - Banting area of Selangor, Malaysia. A regional gravity survey and the high resolution reflection seismic were employed to determine the thickness and areal distribution of the alluvial sedimentary basin as well as to investigate the depth and topography of the bedrock in the study area. The sedimentary basin hosts one of the most important coastal alluvial aquifer which was used to cater the shortage of domestic water supply during the worst water crisis that hit the state of Selangor in 1998. The surface geological map shows that in general 70% of the study area is covered by Quaternary deposits of Beruas, Gula and Simpang Formations which overlie the sedimentary bedrock of Kenny Hill Formation. The Beruas Formation consists of mainly clay, sandy clay and peat of Holocene fluviatile-estuarine deposits, whereas the Gula Formation represents Holocene marine to estuarine sediments which mostly consists of clay and minor sand. The Simpang Formation (Pleistocene) is a continental deposit comprising of gravel, sand, clay and silt. The underlying Kenny Hill Formation consists of a monotonous sequence of interbedded shales, mudstones and sandstones. The rock is Carbonaceous in age and it forms an undulating surface topography in the eastern part of the study area. A total of 121 gravity stations were established using a La Coste & Romberg gravity meter and the elevations of most of the stations were determined barometrically using Tiernan-Wallace altimeters. The high resolution seismic reflection using the common mid point (CMP) or roll along technique was carried out using a 24 channel signal enhancement seismograph and high frequency geophones. A total length of about 1.7 km stacked seismic section has been acquired in this survey and a nearby borehole data was used for interpretation. A relative Bouguer anomaly map shows an elongated zone of low gravity anomaly trending approximately NW-SE which is interpreted to be the deposition center of the Quaternary basin. The interpreted gravity profiles running across the central area of the study area show that the basin has thickness varies from tenth to several hundred meters with maximum depth to bedrock of about 275m. A gravity profile which passes through the eastern edge of the basin was modeled with depth to bedrock of about 178m below ground which agrees very well with those obtained from the interpreted seicmic section and borehole data. The stacked seismic section shows several high amplitude parallel to sub-parallel reflection overlying discontinuos and low reflection pattern. Reflections on the eastern part of the section is much shallower than the one observed on the western part which clearly indicates the presence of basinal structure with a total interpreted depth to bedrock of about 200 meters.
    MeSH terms: Aluminum Silicates; Geology; Malaysia; Surveys and Questionnaires; Running; Soil; Water; Water Supply; Hypogravity; Groundwater
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