878 research outputs found
Integrated waveguide and nanostructured sensor platform for surface-enhanced Raman spectroscopy
Limitations of current sensors include large dimensions, sometimes limited sensitivity and inherent single-parameter measurement capability. Surface-enhanced Raman spectroscopy can be utilized for environment and pharmaceutical applications with the intensity of the Raman scattering enhanced by a factor of 106. By fabricating and characterizing an integrated optical waveguide beneath a nanostructured precious metal coated surface a new surface-enhanced Raman spectroscopy sensing arrangement can be achieved. Nanostructured sensors can provide both multiparameter and high-resolution sensing. Using the slab waveguide core to interrogate the nanostructures at the base allows for the emission to reach discrete sensing areas effectively and should provide ideal parameters for maximum Raman interactions. Thin slab waveguide films of silicon oxynitride were etched and gold coated to create localized nanostructured sensing areas of various pitch, diameter, and shape. These were interrogated using a Ti:Sapphire laser tuned to 785-nm end coupled into the slab waveguide. The nanostructured sensors vertically projected a Raman signal, which was used to actively detect a thin layer of benzyl mercaptan attached to the sensors
The relation between solar cell flight performance data and materials and manufacturing data Final report
Flight performance data for solar cell power systems in satellites and correlation with manufacturing methods and material
The application of fault signature analysis in Tenaga Nasional Berhad Malaysia
Unplanned electrical power outages are a major concern to power utilities throughout the whole world. Unfortunately, power outages will continue to occur and they cannot be fully prevented. It could be the result of lightning strikes, tree encroachment, or equipment failure. However, the impact can be reduced if power system operators are equipped with the appropriate tools to analyze the root cause of the failure. Without sufficient tools to identify the nature of a fault, the restoration process could be delayed because the operator does not know whether it is safe to normalize the isolated line. This paper describes the new and simplified fault signature analysis approach on Tenaga Nasional Berhad using a digital fault recorder. The research focuses on the contribution of the lightning strike and tree encroachment to the overhead line tripping in Malaysi
Influence of thermal radiation on unsteady MHD free convection flow of jeffrey fluid over a vertical plate with ramped wall temperature
Influence of thermal radiation on unsteady magnetohydrodynamic (MHD) free convection flow of Jeffrey fluid over a vertical plate with ramped wall temperature is studied. The Laplace transform technique is used to obtain the analytical solutions. Expressions for skin friction and Nusselt number are also obtained. Results of velocity and temperature distributions are shown graphically for embedded parameters such as Jeffrey fluid parameter , Prandtl number P r, Grashof number G r, Hartmann number H a, radiation parameter R d, and dimensionless time τ. It is observed that the amplitude of velocity and temperature profile for isothermal are always higher than ramped wall temperature
Analysis of heat transfer for unsteady MHD free convection flow of rotating Jeffrey nanofluid saturated in a porous medium
In this article, the influence of thermal radiation on unsteady magnetohydrodynamics (MHD) free convection flow of rotating Jeffrey nanofluid passing through a porous medium is studied. The silver nanoparticles (AgNPs) are dispersed in the Kerosene Oil (KO) which is chosen as conventional base fluid. Appropriate dimensionless variables are used and the system of equations is transformed into dimensionless form. The resulting problem is solved using the Laplace transform technique. The impact of pertinent parameters including volume fraction φ, material parameters of Jeffrey fluid λ1, λ, rotation parameter r, Hartmann number Ha, permeability parameter K, Grashof number Gr, Prandtl number Pr, radiation parameter Rd and dimensionless time t on velocity and temperature profiles are presented graphically with comprehensive discussions. It is observed that, the rotation parameter, due to the Coriolis force, tends to decrease the primary velocity but reverse effect is observed in the secondary velocity. It is also observed that, the Lorentz force retards the fluid flow for both primary and secondary velocities. The expressions for skin friction and Nusselt number are also evaluated for different values of emerging parameters. A comparative study with the existing published work is provided in order to verify the present results. An excellent agreement is found
PREVALENCE AND FACTORS ASSOCIATED WITH OBESITY AMONG ADULT AT THE KAMPUNG KOLAM, EAST COAST MALAYSIAN PENINSULA-A CROSS SECTIONAL STUDY
Objective: This study assesses the prevalence of obesity and its associated factors among adults aged 18 y and above at the Kampaung kolam, Kuala Terengganu, Malaysia.Methods: This cross-sectional survey comprised of a semi-structured face to face interview questionnaire and collected anthropometric measurements and sex specific waist circumference in cm. The study population was 70 in total with 21 (30%) males and 49 (70%) females aged 18 y and above were selected by universal sampling. Body mass index (BMI) was used for weight status and sex specific waist circumference (WC) in cm was used for assessment of abdominal or central obesity at risk of metabolic complications associated with obesity.Results: Among men, the prevalence of underweight was 9.5%, normal weight 57.1%, overweight 14.3% and obesity 19.1%, while among women, the prevalence of underweight was 12.2%, normal weight 53.1%, overweight 14.3% and obesity 20.4%. Overall, 18 (25.7%) was obese and 52 (74.3%) was non-obese while sex specific WC in cm 19 (27.1%) was abdominal obese who were at risk of metabolic complication associated with obesity and 51 (72.9%) was not at risk. In chi-square association tests revealed that among respondents, currently married, unemployed and having family history with obesity were associated with generalized obesity while respondents who were currently married and having fast food frequently were associated with abdominal obesity and respondents who being currently married, unemployed and having fast food frequently were more likely to obese in generalized as well as abdominally.Conclusion: There was no association between generalized, abdominal and generalized and abdominal obesity with age, gender, education, flat floor structure, dietary patterns and habits, physical activities, sleep pattern and knowledge and attitude level towards obesity but those factors can be utilized in effective health promotion programmers of weight management strategies by targeting those factors in design for prevention of hypertension, diabetes and related cardio vascular diseases CVD
A Case Report of Metastatic Castration-Resistant Prostate Cancer Harboring a \u3ci\u3ePTEN\u3c/i\u3e Loss
The treatment landscape of metastatic castration-resistant prostate cancer (mCRPC) has dramatically improved over the last decade; however, patients with visceral metastases are still faced with poor outcomes. Phosphatase and tensin homolog (PTEN) loss is observed in 40%–60% of mCRPC patients and is also associated with a poor prognosis. Several PI3K/AKT/mTOR pathway inhibitors have been studied, with disappointing anti-tumor activity. Here, we present a case of a patient with heavily treated mCRPC who had a modest tumor response to concurrent carboplatin, abiraterone acetate/prednisone, and liver-directed radiation therapy. We discuss the potential rationale supporting the use of this combination therapy and its safety in mCRPC. While the underlying basic mechanism of our patient’s anti-tumor response remains uncertain, we suggest that further prospective studies are warranted to evaluate whether this combination therapy is effective in this population of patients with pre-treated mCRPC and PTEN loss
SIMULATION OF KORTEWEG DE VRIES EQUATION
Korteweg de Vries (KdV) equation has been used as a mathematical model of shallow water
waves. In this paper, we present one-, two-, and three-soliton solution of KdV equation. By
definition, soliton is a nonlinear wave that maintains its properties (shape and velocity) upon
interaction with each other. In order to investigate the behavior of soliton solutions of KdV
equation and the interaction process of the two- and three-solitons, computer programs have been
successfully simulated. Results from these simulations confirm that the solutions of KdV equation
obtained are the soliton solutions. (Abstract by authors
Numerical solution of unsteady free convection flow in a second grade fluid
In this paper, the problem of unsteady free convection flow moves along a vertical plate in a second grade fluid is studied. The vertical plate with constant temperature is considered. The dimensional governing equations are transformed into non dimensional equations using appropriate dimensionless variables and solved numerically using Finite Difference Method. Numerical results for velocity and temperature profiles are displayed graphically for viscoelastic parameter, Grashof number and Prandtl number and discussed in details. It is found that, increasing the values of Grashof number and time leads to increase in the velocity profiles. Increasing the values of the Prandtl number and viscoelastic parameter is found to decrease the velocity profile. It is further found that, increasing the values of Prandtl number tends to decrease the thermal boundary layer thickness
- …