Optimised transmission tower earthing: experience in design and operation

A large percentage of transmission line outages in Malaysia are due to lightning activity with backflashover being the main cause. Previous investigations have indicated that tower footing earth resistance is one of the main factors in reducing the occurrence of backflashovers. The present studies review some of the tower earthing design options. From this standard designs are proposed together with a practical method of optimising the design based on soil resistivity measurement data. The process is presented via a flowchart which includes the main measurement and design steps. This allows different standard designs to be selected to suit the type of soil structure at the site of the proposed transmission tower. Where measurements indicate a high resistivity layer with underlying low resistivity soil, an electrode design relying more on driven rods is used. Conversely, a design using more horizontal electrode would be selected where the soil structure is of low resistivity above high. Some practical methods are also described which can be included in the design to improve the ease with which maintenance testing can be carried out. The results of trial installations on selected towers have been performed and the results are discussed

Multiple cavitating pulmonary nodules secondary to Hodgkin's lymphoma

We report a 26-year old lady who presented with chronic cough and breathlessness associated with subtle TB symptoms for 1 year. Her CT thorax showed multiple cavitating pulmonary nodules with mediastinal and cervical lymphadenopathy. Cervical lymph node biopsy and CT-guided pulmonary biopsy at our centre confirmed the diagnosis of Hodgkin’s lymphoma with pulmonary infiltrations. She was successfully treated with ABVD regime but later developed life-threatening bleomycin-induced pulmonary fibrosis. Sadly, she succumbed to respiratory failure due to severe pneumonia with possibility of bleomycin-induced pulmonary fibrosis. Multiple cavitating pulmonary nodules secondary to lymphoma is rare and in TB endemic area, it may result in delayed diagnosis and treatment

Awareness of vesicovaginal fistula among health workers in some health facilities of Zamfara state, Northwest Nigeria

The prevalence of obstetric fistula in Nigeria was found by 2008 National Demographic Health Survey (NDHS) to be 0.4%, suggesting there are approximately 150,000 women of reproductive age currently living with, or who have previously had, obstetric fistula. Fistula prevalence is higher in Northern than in Southern Nigerian zones. For instance, the prevalence of fistula in North Central Nigeria is 0.8%, followed by 0.5% in the North East and 0.3% in North West Nigeria. This study aimed at understanding the knowledge and level of understanding of Health workers in some selected hospitals and clinics in Zamfara State, North West Nigeria. The study was both a descriptive cross sectional and qualitative study of health personnel working in some health facilities in Zamfara State to gain an insight of their understanding and practice about vesicovaginal fistula (VVF) which is a common obstetric and maternal health complication among women in Nigeria during or after delivery. 68.3% of the respondents were females while 31.7% were males. There is no specialist consultant or fistula surgeon among the health personnel interviewed as only 11.7% of them were medical doctors while the remaining are nurses, midwives or community health extension workers. On their knowledge of fistula, 97.6% of them have heard of VVF, and 87% of them were of the opinion that early marriage causes complications during delivery or giving birth. Also 88% of them were aware of VVF as one of the problems associated with early girl-child marriage while only 61% of them knew that obstructed or delayed labour causes VVF. It is important to train and equip the lower cadre health and clinic personnel on VVF and how to prevent it as the management of VVF requires a specialized knowledge and expertise

Structural conformation of Bacillus stearothermophilus F1 protease and effect of modification on its thermostability

The extracellular F1 serine protease, produced by a thermophilic Bacillus stearothermophilus F1, has been isolated and characterized as one of a serine protease. F1 protease was stable in the pH range of 8.0 to 10.0, with an optimum activity at pH 9.0. The enzyme was stable for 24h at 70°C (Rahman et al., 1994)

Evaluation of bleeding pattern,side effect and satisfaction with subdermal contraceptive etonogesterel implant(implanon): a comparison between postpartum and non postpartum user

Objective : The aim of this study was to compare the bleeding pattern, side effects and level of satisfaction between postpartum and non post partum Implanon® users. Study design : A prospective study was conducted from July 2010 till June 2012 at Hospital Tengku Ampuan Afzan, Pahang. A total of 110 women ( 60 postpartum and 50 non postpartum women ) who had Implanon inserted, were followed up at 3 and 6 months after insertion. The bleeding pattern, side effects and satisfaction level were analyzed and compared accordingly. Result : The mean age for postpartum group was 31.2 and for non postpartum group was 33.6.There was no difference in body mass index and parity between these two groups. Majority of the Implanon® users were using Oral Contraceptive Pills as previous method of contraception. There was no difference in bleeding pattern at 3 months between postpartum and non postpartum women. However there was significant difference at 6 months for amenorrhoea and infrequent bleeding pattern (p value of 0.005 and 0.024 respectively). About half of the users from each group had the side effects of weight gain ( 53.3% postpartum vs 56.0% non postpartum ) There was significant difference of side effects of headache and acne between postpartum and non postpartum women. Despite the side effects, majority of the users from both groups satisfied with this method of contraception ( 93.3% of postpartum and 88.0% of non postpartum ). Conclusion : Implanon® is a highly effective long acting reversible hormonal contraception. Weight gain was the most common side effect reported. There was significant difference in bleeding patterns and non menstrual side effects between post partum and non postpartum users of Implanon® in the first six months of usage. The overall satisfaction was high among most users

Physico-mechanical properties of polymer concrete containing micro-filler of palm oil fuel ash

Objective of this study is to present a research conducted on ground (fine) and unground (coarse) POFA in polymer concrete (PC) followed by determination on the physico-mechanical properties of PC. Physical properties of micro-fillers and mechanical properties of produced PCs were characterized. Calcium carbonate and silica sand were also used as micro-fillers for comparison purpose. The samples were subjected to compression and flexural. Morphology images of the particles were captured under morphology test to support the findings. Results showed that fine POFA micro-filler has a highly promising potential in becoming PC filler compared to coarse micro-filler. Additionally, its produced PC had comparable strength to PC with calcium carbonate. From the strength development and sustainability stand point, fine POFA has demonstrated its capability to produce quality and sustainable P

A practical method for optimised earth electrode designs at transmission towers exposed to lightning

A large percentage of transmission line outages in Malaysia are due to lightning activity with backflashover being the main cause. Previous investigations have indicated that tower footing earth resistance is one of the main factors in reducing the occurrence of backflashovers. The present studies review some of the tower earthing design options. From this standard designs are proposed together with a practical method of optimising the design based on soil resistivity measurement data. The process is presented via a procedure which includes the main measurement and design steps. This allows different standard designs to be selected to suit the type of soil structure at the site of the proposed transmission tower. Where measurements indicate a high resistivity layer with underlying low resistivity soil, an electrode design relying more on driven rods is used. Conversely, a design using more horizontal electrode would be selected where the soil structure is of low resistivity above high. Trial installations using the newly designed electrode arrangements have been conducted and preliminary results indicate significant improvements in lightning performance

Bilateral sinonasal inverted papilloma: case report and literature review

Objective: To describe a rare case of bilateral sinonasal inverted papilloma and review the relevant literature. Design: Case report. Materials and Methods: Medical record review and literature search. Results: A 50-year-old gentleman presented with bilateral nasal polyposis involving posterior ethmoid and sphenoid sinuses. With clinical diagnosis of benign inflammatory polyposis, he underwent bilateral functional endoscopic sinus surgery. The histopathological examination revealed the diagnosis of bilateral inverted papilloma. He remains disease free after 5 years follow up. A literature review on the subject is presented. Conclusion: This case highlighted the unique presentation of sinonasal inverted papilloma as a bilateral disease and in the posterior group of paranasal sinuses

Implementing k-means clustering algorithm in collaborative trip advisory and planning system

Fueled by the help of the Internet, more and more tourists nowadays tend to plan trips by themselves in order to have trip plans that meet their preferences and convenience perfectly. However, tourists may face some problems when they plan a trip by themselves, which makes the whole trip planning process challenging and tiring. These problems include extensive tourism information, manually constructing an itinerary for a trip and difficulty in satisfying the needs of all trip participants. Therefore, a web-based trip planning system is proposed in this project to solve all these problems in order to help tourists in planning their desired trips more effectively and efficiently. This system will help users to search for attractions and restaurants in Southeast Asian countries faster by providing filtering and prioritizing features. This system also facilitates the decision-making process of tourists when choosing places to visit and restaurants by utilizing the power of word-of-mouth (reviews). Besides, this system will aid tourists by reducing the need to manually construct the itinerary for a trip. The k-means clustering algorithm will be used to auto-arrange the trip itinerary to ensure places close to each other are arranged to be visited on the same day so that tourists can save on unnecessary transport costs and time. Lastly, this system promotes collaborative trip planning by providing a platform for all the participants in a trip to discuss and plan their trip together

Association of MMP-9 gene polymorphisms with nephrolithiasis patients

Background: Nephrolithiasis is one of the causes which lead to chronic kidney disease (CKD). Matrix metalloproteinases (MMPs) are endopeptidases degrading extracellular matrix which correlate with the pathogenesis of atherosclerosis. The current study was designed to analyze the association of (R279Q, C1562T) polymorphism of MMP-9 with nephrolithiasis patients. Methods: Genotyping of MMP-9/R279Q and of MMP-9/C1562T polymorphism were carried out by PCR-based restriction digestion method. Serum level of MMP-9, oxidative stress marker, MDA, and uric acid were measured in patients and control. Results: Allele frequencies of the MMP-9/C1562T polymorphism for C and T allele were 71.25% and 28.75% in patients, 87.08% and 12.92% in control respectively. The homozygote TT was more frequent in the nephrolithiasis patients group, while T allele frequency was significantly higher in the nephrolithiasis patients group than in the control group. The patients with CT and TT genotype showed a significant increase in serum MMP-9, Total Oxidant Status (TOS), Oxidative Stress Index (OSI), Malondialdehyde (MDA), and uric acid when compared to CC genotype in patients with nephrolithiasis. The R279Q polymorphism site with regard to the relationship with nephrolithiasis was not significant. Conclusion: The result indicates that patients with TT genotype had an increased risk of stones. Also, the results demonstrate that TT allele of the C1562T polymorphism in the MMP-9gene is related with an increase of oxidative stress in nephrolithiasis patients and may possibly impose a risk for cardiovascular diseases in patients with TT genotype of MMP-9