21 research outputs found
Partial Replacement of Toluene Diisocyanate (TDI) on Mechanical Properties of Old Newspaper Filled Diphenylmethane Diisoeyanale (MDI) Foam Composites
The mechanical properties of partial replacement of toluene diisocyanate (TDI) in diphenylmethane 4,4’-diisocyanate of old newspaper (ONP) foam composite based on polyurethane (PU) was investigated. The results indicate that an increase of ONP filler content leads to an increased compressive strength, elastic modulus and hardness. At constant ONP content, foam composites produced by partial replacement of TDI in MDI result in higher values of hardness, compressive strength and elastic modulus compared to the ONP foams control
Detection of haemoglobin S using multiplex ligation-dependent probe amplification and flow-through hybridization techniques: experience in a tertiary hospital
Haemoglobin S (HbS, α2β26GluVal) is a variant haemoglobin resulted from GAGGTG mutation on codon 6 of HBB gene. HbS haemoglobinopathy is uncommon in Malaysia and mainly seen in immigrants. However, Malaysian Indians and Malays are rarely affected. This study reviewed the laboratory findings of patients with HbS and the utilization of multiplex ligation-dependent probe amplification (MLPA) and flow-through hybridization (FTH) in the detection of HbS mutation. HbS was identified and quantified by high performance liquid chromatography (HPLC), capillary electrophoresis (CE) and cellulose acetate gel electrophoresis. Molecular analysis was performed using MLPA, FTH and Sanger Sequencing. Two Africans, three Malays and two Indian individuals aged between 2-31 years were identified from our laboratory. Five patients were homozygous HbS, one was compound heterozygous HbS/β-thalassemia and one was a carrier of HbS. The patients with homozygous HbS had their haemoglobin (Hb) ranging from 7.4-10.2 g/dL with HbS and HbF levels of 58.3-94.7% and 1.5-35.5%, respectively. The Hb of compound heterozygous HbS/β-thalassaemia patients was 5.8 g/dL and was normal in heterozygous HbS. HbS, HbF and HbA2 levels for the HbS/β-thalassaemia and the carrier were 67%, 27.2% and 4.2%, and 38.6%, 0.1% and 2.8%, respectively. Both MLPA and FTH successfully detected HbS mutation in all cases but only FTH could identify the zygosity of the HbS mutation together with underlying concomitant β-thalassaemia in a single test
Early second trimester hCG of maternal serum as predictor marker for pregnancy induced hypertension
Pregnancy induced hypertension (PIH) is commonly encountered in hypertensive
disease in pregnancy (HDP) and important cause of feto-maternal morbidity and
mortality. Abnormal changes of placenta development in PIH leads to abnormal
elevation of second trimester maternal hCG level. Thus, it may have a role in
prediction of PIH. The objective of this study was to evaluate the ability of serum
hCG levels during early second trimester to predict PIH and obstetric outcome at
later gestation. We conducted a cohort study which comprised 34 pregnant women
varying from 14–20 weeks of gestation with serum hCG level taken at points of
recruitment. Serum hCG was measured by a chemiluminescent immunoassay.
Three (8.8%) pregnant women developed late onset PIH while the remainder were
normotensive. The diagnostic performance of second trimester hCG in predicting
PIH as assessed by receiver operator characteristic curve was poor (AUC = 0.398).
Multiple of median (MoM) were used to improve the hCG performance and MoM
of >2 MoM were considered as elevated hCG level. All pregnancies with PIH had
<2 MoM. In normotensive pregnancy, 29 (93.5%) women had hCG <2 MoM and
2 (6.5%) women had hCG >2 MoM (p>0.655). There was no significant association
of hCG level and pregnancy outcome. In conclusion, estimation of second trimester
hCG is a poor predictive marker for PIH. These findings are limited by the less
number of hypertensive cases
Morbidly adherent placenta at extreme prematurity: can major haemorrhage and hysterectomy be prevented?
Morbidly adherent placenta with spontaneous rupture of membrane at extreme prematurity poses poor pregnancy outcome. Various issues on different management modalities still remain perplexed and individual consideration is vital. Two cases of morbidly adherent placenta with symptomatic per vaginal bleeding and spontaneous rupture of membrane at severe prematurity were reviewed and discussed. We found that, active intervention by termination of pregnancy and methotrexate therapy at early gestation can prevent the need of hysterectomy following major obstetrics haemorrhage
Isolation and Characterization of Diazotrophic Rhizobacteria of Oil Palm Roots
Beneficial rhizobacteria were isolated from two different compartments of oil palm roots; the rhizosphere or rhizoplane and the inner root tissues. The root samples were collected from oil palm plantation at Felda Lepar 9, Temerloh Pahang (Block 17, Square 6) (soil pH 4.30; 10:25 0.01M CaCl2). Identification of the isolates was conducted by classical biochemical and physiological tests. Acetylene Reduction Assay (ARA) test was also conducted to quantify the ability of the isolates to fix atmospheric N2. Twenty-nine strains of rhizobacteria were isolated from root samples and were maintained aerobically on N-free solid media. Seven of the isolates were identified as Gram negative while the rest were Gram positive. The isolates were successfully identified as Paenibacillus durus (formerly P. azotofixans), Paenibacillus polymyxa, Azospirillum lipoferum, Herbaspirillum seropedicae and Acetobacter diazotrophicus. The N2 fixation capacities of the isolates ranged from 7.0 x 10-12 to 1.0 x 10-8 mol C2H4/cfu/hour
Detection of partial G6PD deficiency using OSMMR2000-D kit with Hb normalization.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency worldwide including Malaysia. Screening of cord blood for partial G6PD deficiency is important as they are also prone to develop acute haemolysis. In this study, we determined the prevalence of partial G6PD deficient in paediatric population aged 1 month-12 years and normal term female neonates using OSMMR-D kit with haemoglobin (Hb) normalization and compare it with florescence spot test (FST). A total of 236 children, aged between between 1 month-12 years and 614 normal term female neonates were recruited for this study. Determination of normal means for G6PD activity and; cut-off points for partial and severe deficiency were determined according to WHO Working Group (1989). Determination of prevalence for partial deficiency for both groups (female patient) was done using this enzyme assay kit and findings were compared with FST. In this study, 15.7% (18/115) female children were classified as partial G6PD deficient by quantitative enzyme method (G6PD activity: 4.23-5.26U/gHb). However, FST only detected 0.9% (1/115) with minimal G6PD activity. The prevalence of partial G6PD deficiency in female neonate group was 3.42% (21/614) by enzyme assay versus 0.49% (3/614) by FST. This study concluded that our routine screening method using FST was unable to diagnose female heterozygotes. We recommend using this quantitative enzyme assay method by OSMMR-D kit since it was more sensitive in detecting G6PD deficiency in female neonates compared to FST
Interfacial Bonding Mechanisms of Natural Fibre-Matrix Composites: An Overview
The development of natural fiber (NFr) composites for a variety of applications is on the rise. The optimization of the interfacial bonding (IFB) between the reinforcing NFr and polymer matrix is perhaps the single most critical aspect in the development of natural fibre polymer composites (NFPCs) with high mechanical performance. While the IFB is critical in determining the mechanical properties of the NFPCs, such as stress transfer, it is one of the least understood components. This article offers a summary of IFB mechanisms, different modification approaches targeted at lowering incompatibility and improving IFB, and evaluation of the impact of IFB. It has been found that 1) In general, interdiffusion, electrostatic adhesion, chemical reactions, and mechanical interlocking are accountable for the IFB; 2) the incompatibility of the fibre and matrix, which results in poor dispersion of the fiber, weak IFB, and ultimately worse composite quality, may be addressed through strategic modifications; and 3) Interfacial interactions between polymers and nanoparticles (NPs) are significantly improving their performance in areas like thermal, mechanical, robust IFB, and moisture absorption. As a result, this review study could be an important resource for scholars interested in coating and treating NFr to further enhance their surface characteristics
Can Corynebacterium pseudotuberculosis survive in the environment, fomites and flies within infected herd?
Challenges and advancement in water absorption of natural fiber-reinforced polymer composites
Natural fibres (NFRs) composite materials are acquiring popularity in the modern world due to their eco-friendliness and superior mechanical properties. Although it has been shown that determining this is a herculean endeavour in the literature, the water absorption (WA) qualities of the natural fibre (NFR) are crucial in the progressive degradation of the features of the resulting composites. This article seeks to report exhaustively on studies pertaining to the WA attributes of polymer composites reinforced with NFRs. This article provides an overview of NFR, its characterization, and the issues related to its addition to the matrix. The primary purpose of this research study is to investigate existing studies on the problems associated with the creation of cellulosic fibre hybrid composites, water absorption, and its impact on the tensile (TS), flexural (FS), and impact strength (IS) of NFR reinforced composites. We reviewed various surface treatments (ST) applied to NFR, including alkali treatment, silane treatment, acetylation, as well as recent advancements aimed at mitigating WA, enhancing hydrophobicity, and improving the interfacial bonding (IB) between NFR and the polymer matrix (PM). Additionally, we assessed the effectiveness of utilizing nanoparticles (NAPs) in specific ST of NFR to minimize water absorption