A Reconfigurable Radiation Pattern Annular Slot Antenna

This paper contemplate a theoretical analysis of a pattern reconfigurable antenna using annular slot antenna operating in low frequency. A shorting pin is inserted to allow the annular slot antenna to have an omnidirectional radiation pattern like a monopole antenna. The reconfigurable antenna consists of numerous metal cylinders arranged around the annular slot antenna. By controlling pin diodes associated with the metal cylinders, the antenna is capable of working up in different directions with a maximum working beam angle of 11.25° at a frequency of 1.05 GHz

Challenges in managing dementia in a primary health care setting: A case report

Dementia is a condition that is frequently associated with ageing. However, many fail to recognise that dementia is a treatable condition if detected early. This case report illustrates a 64-year-old man who was initially presented in a primary health care (PHC) centre in Kuala Lumpur Malaysia, with gradual changes in his behaviour. Initial assessment concluded that he suffered from depression and he was treated accordingly. However, over time his condition deteriorated and the diagnosis was re-evaluated from depression to dementia when he developed poor cognitive and memory function. The patient defaulted on his follow-up appointments due to poor understanding of the illness and poor family support.Keywords: dementia; elderly; primary health car

The frequency of carcinoma in solitary thyroid nodules and in multinodular goitres

A retrospective study of all patients with goitre seen from 1988 to 1992 inclusive  at the Muhimbili Medical Centre, Dar es Salaam was made to determine the  frequency of malignancy in patients with solitary non-toxic thyroid nodule (STN) and in those with multinodular goitre (MNG). There were 60 cases of STN and 178 with MNG. Nodular goitre was found to be predominantly a disease of females with sex ratios of M:F;1:7 for the STN group and of M:F;1:13 in the MNG group. The final  diagnosis in all cases was made by histology which found malignancy in 10% of STN and in 5% of MNG patients, a difference which was not statistically significant. Patients in the 20-29 years age group with STN appeared to have an increased risk of malignancy when compared with the MNG group. No cause for this was  discovered. The predominant malignancy in the STN group of patients was papillary carcinoma, while that in the MNG group was follicular carcinoma. Key Words: thyroid, malignancy, solitary nodule, multinodular goitr

Mutual Coupling Reduction Between Two PIFA Using Uni-Planar Fractal Based EBG for MIMO Application

Fractal Structures based on Electromagnetic bandgap (EBG) can contribute to the mutual coupling reduction between microstrip antennas due to its capability of suppressing surface waves propagation in a given frequency range. In this paper, a new arrangement of one layer Uni-Planar Fractal based on EBG (UPF-EBG) structure is analysed using the commercial finite element full wave solver High-Frequency Structure Simulation (HFSS version 17.0). The structure without any shorting pins or vias is based on a well-known fractal structure called Sierpinski carpet, within which two iterations have been applied as planner EBG between two PIFA for increase isolation issue. The total dimensions of the PIFA antenna are 40 mm × 68 mm × 1.6 mm and operate at 2.65 GHz approximately which is defined for wireless Long Term Evolution (LTE) MIMO application. Here a compact periodic lattice (2 × 3 EBG structures are joint to improve the mutual coupling) inserted between E-plane coupled PIFA array, and precise performance study is implemented to investigate the mutual coupling. As a result, significantly more than 30 dB mutual coupling reduction is noticed from the simulations

Prevention of Radiocontrast-Induced Nephropathy after Coronary Angiography: N-Acetylcysteine plus Saline Hydration versus Saline Hydration

Purpose: To compare the incidence of radiocontrast-induced nephropathy (RCIN) in patients undergoing coronary angiography pretreated with N-acetylcysteine NAC plus saline hydration or saline hydration alone and to determine the association between various risk factors and RCIN.Methods: Patients were retrospectively evaluated over a one-year period. RCIN was defined as an acute rise in serum creatinine of at least 0.5 mg/dl or more than 25 % from baseline value. SPSS software, version 13 was used for data analysis.Results: Overall, 299 patients were studied. Thirteen patients (4.3%) developed RCIN. RCIN was 3.3 % in patients treated with hydration, and 8.3 % in patients treated with NAC plus hydration (p = 0.09). Inpatients with RCIN, the changes in creatinine and % change in creatinine after 24 h were significantly lower in the NAC plus hydration group (p = 0.039 and p = 0.042, respectively). RCIN was significantly associated with male gender (p = 0.017), history of renal failure (p = 0.006), ischemic heart disease (p =0.003), and diuretic treatment (p = 0.013).Conclusion: NAC plus saline hydration may not be more effective than saline hydration alone in decreasing RCIN after coronary angiography. Additional efforts to find an ideal preventive treatment are needed

A noniterative numerical solution for step-heated semi-infinite solid with temperature dependent thermal properties

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24513/1/0000791.pd

A numerical scheme for unsteady flow of a viscous fluid between elliptic plates

A new continuation method has been developed to solve the nonlinear eigenvalue problem describing the unsteady, squeezing flow of a viscous fluid between elliptic plates. Unlike the numerical schemes previously used (e.g. homotopy algorithm), the present scheme is conceptually simple, noniterative, insensitive to the first approximation and works for all values of squeeze number S characterizing the flow. The numerical results compare extremely well with those obtained with sophisticated schemes. Since existing numerical data are limited to three sparsely spaced values of S, additional data are reported for systematically spaced values of squeeze number S and ellipticity parameter [beta]. Although the scheme has been applied to a specific problem, it appears potentially capable of handling a variety of nonlinear eigenvalue problems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24355/1/0000624.pd

Periodic heat transfer in fins with variable thermal parameters

Periodic heat transfer in a convecting fin with temperature dependent thermal conductivity and coordinate dependent heat transfer coefficient, is analyzed using a perturbation analysis. The zero-order problem, which corresponds to steady-state fin behaviour, is solved by quasilinearization. A method of complex combination is used, in conjunction with a noniterative numerical scheme, to solve the first-order and the second-order problems. The nonlinear nature of the problem gives rise to a nonoscillatory component in the second-order term, which causes a net change in the mean values of temperature and heat transfer rate. The direction of change depends on the thermal conductivity parameter [alpha]. For [alpha] [mu] 0, the mean temperature is increased, while the mean heat transfer rate is decreased. For [alpha] < 0, the effect is opposite. Detailed results showing the effects of various parameters on temperature distribution, heat transfer rate and time-averaging fin efficiency are presented and discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24300/1/0000566.pd

Pilot-scale recovery of low molecular weight organic acids from anaerobically treated palm oil mill effluent (POME) with energy integrated system

Low molecular weight organic acids such as acetic acid, propionic acid and butyric acids generated from partial anaerobic treatment of palm oil mill effluent (POME) were recovered using pilot scale filtration and evaporation system. Mechanical filter press (14 L) was used for removing solid fractions and fraction distillation unit (40 L) for evaporation and clarification of concentrated acid from POME. Clarification using rotary evaporator was found to be more suitable than distillation column. Due to the presence of more than 90% of water in POME, the final clarified product comprises only 7% of the total volume. The material balance for the overall process was estimated and integrated system for the bioconversion of organic acids into polyhydroxyalkanoates (PHA) was proposed. The recovery of organic acids has a significant and economical impact, since around 50% cost of PHA production is believed to be associated with the substrate itself