The aetiology of dry socket continues to be the subject of intense research. Local disturbances of fibrinolytic activity appear to be the most satisfactory explanation for the pathogenesis of this disorder. The factors that are responsible for local changes in fibrinolytic activity are reviewed and evaluated. In the management of this disorder attention should be directed towards the prevention of local changes in fibrinolytic activity.
Oroantral fistula is an uncommon complication in oral surgery. Although smaller fistulas of less than 5 mm in diameter may close spontaneously, larger fistulas always require surgical closures. The literature review revealed various procedures for the closure of oroantral fistulas. These procedures may be subdivided into local flap, distant flap and grafting. Procedures involving local flaps are usually adequate to close minor to moderate size defects. Those procedures utilizing the buccal mucoperiosteal flap as the tissue closure include straight-advancement, rotated, sliding and transversal flap procedures; while those involving the palatal mucoperiosteum are straight advancement, rotational-advancement, hinged and island flap procedures. The combinations of various local flaps to strengthen the tissue closure are also being advocated. The advantages and the limitations of these procedures are discussed. Distant flaps and bone grafts are usually indicated in the closure of larger defects in view of their greater tissue bulks. Tongue flaps have superseded extra-oral flaps from extremities and forehead for aesthetic reasons and also in view of their similar tissue replacement. Various tongue flap procedures are described. At present, various alloplastic materials such as gold, tantalum and polymethylmethacrylate are infrequently reported in the closure of oroantral fistulas. However, in the light of successful reports over the use of biological materials, collagen and fibrin, in the closure of oroantral fistulas, there seems to be another simple alternative technique for treating oroantral fistulas.
Areca catechu (betel) nut is widely used as a chewing agent. The nut alkaloids have been implicated in the pathogenesis of oral precancerous lesions. Quantitative analysis of the chloroform extracts by gas-liquid chromatography of ten commercial nut samples from Bombay have shown a wide variations In their arecoline contents (0% - 1.4%; mean: 0.7%). Nut samples of Identical processing method also vary in their arecoline levels. These variations were suggested to be due to the difference In the raw materials and processing methods. Comparisons were made between the arecoline contents and the Incidence of oral precancerous lesions from the present studies and also from those of Kerala and Mysore. It was concluded that the difference in nut arecoline contents not only reflect their appeal, potency but also influence upon the incidence of these diseases.
Breast cancer is the most common cancer in Malaysian females. The National Cancer Registry in 2003 and 2006 reported that the age standardized incidence of breast cancer was 46.2 and 39.3 per 100,000 populations, respectively. With the cumulative risk at 5.0; a woman in Malaysia had a 1 in 20 chance of developing breast cancer in her lifetime. The incidence of cancer in general, and for breast cancer specifically was highest in the Chinese, followed by Indians and Malays. Most of the patients with breast cancers presented at late stages (stage I: 15.45%, stage II: 46.9%, stage III: 22.2% and stage IV: 15.5%). The Healthy Lifestyles Campaign which started in the early nineties had created awareness on breast cancer and after a decade the effort was enhanced with the Breast Health Awareness program to promote breast self examination (BSE) to all women, to perform annual clinical breast examination (CBE) on women above 40 and mammogram on women above 50. The National Health Morbidity Survey in 2006 showed that the prevalence rate of 70.35% by any of three methods of breast screening; 57.1% by BSE, 51.8% by CBE and 7.6% by mammogram. The current screening policy for breast cancer focuses on CBE whereby all women at the age of 20 years and above must undergo breast examination by trained health care providers every 3 years for age between 20-39 years, and annually for age 40 and above. Several breast cancer preventive programs had been developed by various ministries in Malaysia; among which are the RM50 subsidy for mammogram by the Ministry of Women, Family and Community Development and the SIPPS program (a call-recall system for women to do PAP smear and CBE) by the Ministry of Health. Measures to increase uptake of breast cancer screening and factors as to why women with breast cancer present late should be studied to assist in more development of policy on the prevention of breast cancer in Malaysia.
This paper aims at identifying the factors that would help to diagnose acute myocardial infarction (AMI) using data from an electronic medical record system (EMR) and then generating structure decisions in the form of linguistic fuzzy rules to help predict and understand the outcome of the diagnosis. Since there is a tradeoff in the fuzzy system between the accuracy which measures the capability of the system to predict the diagnosis of AMI and transparency which reflects its ability to describe the symptoms-diagnosis relation in an understandable way, the proposed fuzzy rules are designed in a such a way to find an appropriate balance between these two conflicting modeling objectives using multi-objective genetic algorithms. The main advantage of the generated linguistic fuzzy rules is their ability to describe the relation between the symptoms and the outcome of the diagnosis in an understandable way, close to human thinking and this feature may help doctors to understand the decision process of the fuzzy rules.
The cost of chemicals prohibits many technically feasible enhanced oil recovery methods to be applied in oil fields. It is shown that by-products from oil palm processing can be a source of valuable chemicals. Analysis of the pyrolysis oil from oil palm shells, a by-product of the palm oil industry, reveals a complex mixture of mainly phenolic compounds, carboxylic acids, and aldehydes. The phenolic compounds were extracted from the pyrolysis oil by liquid-liquid extraction using alkali and an organic solvent and analyzed, indicating the presence of over 93% phenols and phenolic compounds. Simultaneous sulfonation and alkylation of the pyrolysis oil was carried out to produce surfactants for application in oil fields. The lowest measured surface tension and critical micelle concentration was 30.2 mNm(-1) and 0.22 wt%, respectively. Displacement tests showed that 7-14% of the original oil in place was recovered by using a combination of surfactants and xanthan (polymer) as additives.
Introduction: To describe the sociodemographic profile, contraceptive practice, and awareness of HIV infection among unmarried post partum women in the biggest government hospital in Pahang.
Methods: A cross sectional questionnaire-proforma-based study was conducted for one year duration from August 2010 until July 2011 by identifying and recruiting all the unmarried women upon admission for delivery. Basic information were obtained from the use of patients’ case notes, and further related and necessary information were obtained from a direct face-to-face interview based on a proforma.
Results: A total of 121 unmarried women were identified and recruited. The age ranged from 13 to 36 years with a mean age of 21.6 years. 31.4% were teenagers. Only 16% of patients have tertiary education, and 2.5% never had any formal education. About one third of the women were smokers or ex-smokers, 7.5% had consumed alcohol, but none denied ever use of any recreational drugs. Almost 9% has prior history of being sexually assaulted. About three quarter of the women never used any contraceptive method. Majority of the patients (85.1%) were aware of HIV transmission risk; 75% never had any antenatal checkup or booked at late gestation (> 20 weeks); and 45.8% were not aware of any support groups for single mothers. Conclusion: Single unmarried women are associated with disadvantaged sociodemographic profile.
Contraceptive practice was also very low despite significant awareness towards risk of HIV infection. Further follow up, support and care should be offered to these women.
For many developing countries undergoing rapid economic growth and urbanization, trends in nutritional status indicate a decrease in malnutrition with an associated rise in the prevalence of obesity. An understanding of the situation among children in Malaysia is lacking.
To develop a Malay-language version of the Axis II Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) through a formal translation/back-translation process and to summarize available data about the psychometric properties of the translated scales.
A study was carried out to determine the chemical composition of bulk precipitation, throughfall and stemflow in an urban forest in Kuala Lumpur, Malaysia. The mean weekly rainfall recorded during the period of study was 63.2 mm. Throughfall, stemflow and canopy interception of incident precipitation were 77.1%, 1.2% and 21.7% respectively. Bulk precipitation, througfall and stemflow were acidic, the pH recorded being 4.37, 4.71 and 4.15 respectively. In all cases the dominant ions were NO3, SO4, Cl, NH4, K, Ca and Na. Of the ions studied Ca, K, Cl, SO4, Mg and Mn showed net increases in passing through the forest canopy, while NH4, Na, NO3, Zn, H and Fe showed net retention. This study shows that the urban environment of Kuala Lumpur contributes considerable amounts of materials to the atmosphere, as reflected by the high ionic contents in bulk precipitation, throughfall and stemflow.
Many studies have been carried out to produce magnetic resonance imaging (MRI) phantoms as alternative to water phantom. Among the important properties of a phantom are the T1 and T2 relaxation times. The objective of this study is to investigate the T1 and T2 characteristics of the agarose gel phantoms with different relaxation modifier (gadolinium (III) oxide, Gd2O3) concentrations or [Gd2O3]. Six agarose gel phantoms were prepared with different [Gd2O3]. The T1 (fixed echo time (TE) and different repetition time (TR)) and T2 (fixed TR and different TE) measurements on all phantoms were conducted using the 3-T MRI system via spin echo (SE) and turbo spin echo (TSE) sequences, respectively. The signal-to-noise ratio (SNR) of all phantoms was calculated using Image-J software by implementing the region of interest (ROI) analysis. The SNR against TR and SNR against TE curves were fitted to the exponential equations for saturation, T1 and T2 determination. For every phantom, T1 curve demonstrated that the SNR increased exponentially with increasing TR, while T2 curves showed that the SNR decreased exponentially with increasing TE. Gd2O3 was found to successfully act as the relaxation modifier for the T1 but not the T2 curves. The T1 curve started to show saturated SNR (SNRo) and increasing SNRo for TR > 1000 ms and [Gd2O3] = 0.005 g/ml or higher. These behaviours are explained based on the dipole-dipole interaction that increases in phantoms with higher [Gd2O3], thus shortening the T1 relaxation. However, a systematic change in the T2 parameters with increasing [Gd2O3] was not observed. While Gd2O3 has significant effects on T1 relaxation parameters, the T2 relaxation parameters were minimally affected. With a shorter T1, the Gd2O3 added agarose gel can potentially be used as test phantom in fast imaging sequence, e.g. gradient echo pulse sequences.
A case of unicystic ameloblastoma which recurred after 15 years showing unusual histological features is reported. The prominent pseudo-glandular features present are described. This case highlights the importance of extensive histological examination for more characteristic features of ameloblastoma to reach a correct diagnosis.
Resistance spot welding (RSW) of dual phase (DP) steels is a challenging task due to formation of brittle martensitic structure in the fusion zone (FZ), resulting in a low energy capacity of the joint during high-rate loading. In the present study, in situ postweld heat treatment (PWHT) was carried out by employing a double pulse welding scheme with the aim of improving the mechanical performance of DP590 steel resistance spot weld joint. Taguchi method was used to optimize in situ PWHT parameters to obtain maximum peak load and failure energy. Experiments were designed based on orthogonal array (OA) L16. Mechanical performance was evaluated in terms of peak load and failure energy after performing low dynamic tensile shear (TS) test. Microstructural characterization was carried out using a scanning electron microscope (SEM). The results show that improvements of 17 and 86% in peak load and failure energy, respectively, were achieved in double-pulse welding (DPW) at optimum conditions compared to traditional single-pulse welding (SPW). The improvement in mechanical performance resulted from (i) enlargement of the FZ and (ii) improved weld toughness due to tempering of martensite in the FZ and subcritical heat affected zone (SCHAZ). These factors are influenced by heat input, which in turn depends upon in situ PWHT parameters.
Automobile, aerospace, and shipbuilding industries are looking for lightweight materials for cost effective manufacturing which demands the welding of dissimilar alloy materials. In this study, the effect of tool rotational speed, welding speed, tilt angle, and pin depth on the weld joint were investigated. Aluminum 5052 and 304 stainless-steel alloys were joined by friction stir welding in a lap configuration. The design of the experiments was based on Taguchi's orthogonal array for conducting the experiments with four factors and three levels for each factor. The microstructural analysis showed tunnel defects, micro voids, and cracks which formed with 0° and 1.5° tilt angles. The defects were eliminated when the tilt angle increased to 2.5° and a mixed stir zone was formed with intermetallic compounds. The presence of the intermetallic compounds increased with the increase in tilt angle and pin depth which further resulted in obtaining a defect-free weld. Hooks were formed on either side of the weld zone creating a mechanical link for the joint. A Vickers hardness value of HV 635.46 was achieved in the mixed stir zone with 1000 rpm, 20 mm/min, and 4.2 mm pin depth with a tilt angle of 2.5°, which increased by three times compared to the hardness of SS 304 steel. The maximum shear strength achieved with 800 rpm, 40 mm/min, and a 4.3 mm pin depth with a tilt angle of 2.5° was 3.18 kN.
The results of the present investigation have shown the usefulness of suprofen in the control of pain following surgical removal of impacted wisdom tooth. The regime of 200 mg. q.d.s. orally, was shown to be satisfactory in the control of postoperative pain. Pain was rapidly controlled by the 1st hour after ingestion and subsequently maintained at a low profile until is was completely abolished by the 8th hour of the postoperative period.
Allometry of shoot extension units (hereafter termed "current shoots") was analyzed in a Malaysian canopy species, Elateriospermum tapos Bl. (Euphorbiaceae). Changes in current shoot allometry with increasing tree height were related to growth and maintenance of tree crowns. Total biomass, biomass allocation ratio of non-photosynthetic to photosynthetic organs, and wood density of current shoots were unrelated to tree height. However, shoot structure changed with tree height. Compared with short trees, tall trees produced current shoots of the same mass but with thicker and shorter stems. Current shoots with thin and long stems enhanced height growth in short trees, whereas in tall trees, thick and short current shoots may reduce mechanical and hydraulic stresses. Furthermore, compared with short trees, tall trees produced current shoots with more leaves of lower dry mass, smaller area, and smaller specific leaf area (SLA). Short trees adapted to low light flux density by reducing mutual shading with large leaves having a large SLA. In contrast, tall trees reduced mutual shading within a shoot by producing more small leaves in distal than in proximal parts of the shoot stem. The production of a large number of small leaves promoted light penetration into the dense crowns of tall trees. All of these characteristics suggest that the change in current shoot structure with increasing tree height is adaptive in E. tapos, enabling short trees to maximize height growth and tall trees to maximize light capture.