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Musculoskeletal based finite element analysis of femur after total hip replacement
No full textThis article evaluates the effect of stress variation on adult femur following total hip replacement using musculoskeletal-based finite element analysis. The aim was to study the changes in stress distribution in the femur after total hip replacement by providing simulated in vivo loading and boundary conditions. The loading and boundary conditions were generated using a musculoskeletal modelling software 'AnyBody' and were applied on femur model, generated from the computed tomography (CT) scan data for standing posture of male patient. The results showed considerable variation in stress distribution pattern in the femur before and after total hip replacement, the metallic implant taking major loads of human body and transferring very less loads to the femur
Rectangular-core large-mode-area photonic crystal fiber for high power applications: design and analysis
No full textA rectangular-core large-mode-area photonic crystal fiber structure has been designed based on the principle of higher order mode filtering by introducing fluorine-doped material rods in the cladding region. The proposed structure has an effective-mode area of fundamental mode (FM) as large as 2147 μm22147 μm2 at 1.064 μm with nominal loss of 1.36×10−2 dB/m1.36×10−2 dB/m and 9.34 dB/m9.34 dB/m at first higher order mode (FHOM), which confirms effective single-mode operation after ∼2.14 m∼2.14 m propagation length. The same structure offers effective-mode area of 5688 μm25688 μm2 a
Optimization of energy and fluence of N2+ ions in the conversion of Al2O3 surface into AlN at room temperature
No full textThe work presents a systematic study of energetic N2+ ion interaction with the clean Al2O3 surface at room temperature. Energetic N2+ ions with energies ranging from 0.1 to 5 keV were bombarded onto the c-plane Al2O3 surface in situ in a UHV system equipped with X-ray Photoelectron Spectroscopy. Survey scans and core level spectra of Al(2p), O(1s), N(1s) were recorded as a function of ion fluence. Survey scans of XPS are used for the compositional analysis, while deconvoluted core level spectra are used to identify the evolution of the chemical bonding. Energetic dependence of N2+ ions occupying interstitial and substitutional sites in Al2O3 lattice are probed to follow the surface evolution. Results show that maximum thickness of surface is nitride by 5 keV N2+ ion with an optimal fluence of 1.5 × 1015 ions/cm2. This modified surface can be used as a template for low defect III-nitrides growth, with enhanced lattice matching than on bare c-Al2O3
Holographic diffuser for multichannel restricted displays
No full textDiffusers play an important role in modern days display technology. Holographic diffusers offer effective control on various parameters of the diffused light like diffusion angle, uniformity of light etc. Present work reports a procedure for realization of a holographic diffuser through which multichannel restricted view display is achieved such that information can be conveyed to and viewed from multiple selective viewpoints only. Such type of diffusers will be helpful in enhancing security feature of the displayed information by enabling only authenticated persons to have access to the information. Fabrication process of the holographic diffuser is described and experimental results are discussed
Design and modelling of dispersion-engineered rib waveguide for ultra broadband mid-infrared supercontinuum generation
No full textWe report a dispersion-engineered As2Se3 chalcogenide glass rib waveguide structure for ultra broadband mid-infrared supercontinuum generation across molecular ‘fingerprint region’. The proposed rib waveguide structure offers non-linear coefficient as high as 18,250 W−1 km−1 at 2.5 μm. Supercontinuum spectrum spanning 2–15 μm, which not only covers the both atmospheric transparent windows (3–5 μm and 8–13 μm) in the mid-infrared domain but also covers the important molecular ‘fingerprint domain’, is obtained using only 4 mm-long rib waveguide structure. To the best of our knowledge, such broadband mid-infrared supercontinuum spectrum in As2Se3-based chalcogenide waveguide geometry is reported for the first time. The proposed design of rib waveguide has potential for robust, integrated and low-cost supercontinuum sources in various applications including frequency comb generation, chemical sensing, food quality control and early cancer diagnostics
Plausibility of variable coverage high range spraying: Experimental studies of an externally air-assisted electrostatic nozzle
No full textA system for spraying liquid pesticides to crops and orchards combines an induction based electrostatic nozzle and externally air-assisted manually controlled mechanical device. In this paper, an innovative concept has been executed for variable coverage high range spraying through an external air-assistance system, which supplies compressed air to assist the finely divided charged liquid droplets by farming a virtual covering around the fine mist of liquid spray. External air-assistive device consists of movable support for air supplies whose variation of cone angle is from parallel spray center line (0°) to maximum spray cone angle (25°). This provides a means to transport electrostatically charged fine mist of liquid droplets to intended target with variable spray coverage angle of target, applicable in high wind and transient conditions with enhanced performance without degradation of charge-to-mass ratio. The results of applied induction electrification process were characterized by a charge-to-mass ratio as a function of applied voltage, target distance, and wind current. It has been shown that the wind current has an insignificant (p value = 0.021615) and significant (p value = 0.000325) effects on the performance of the electrostatic nozzle at 99% confidence level with and without external air-assistive mechanical device respectively. The experimental results are in good agreements with proposed concept
Assessment of the effectiveness of DRASTIC in predicting the vulnerability of groundwater to contamination: a case study from Fatehgarh Sahib district in Punjab, India
No full textThe quality of groundwater has been declining in the Fatehgarh Sahib district of Punjab, India, over the last decade due to the enormous increase in the number of tube wells for the agricultural activities. The vulnerability of groundwater to contamination in the district was assessed using the DRASTIC model. Validation of vulnerable zones was undertaken using the chemical analysis of groundwater samples from the district. Based on this investigation, the inherent problems associated with the DRASTIC model are discussed as potential measures to improve the assessment of groundwater vulnerability
Gold nanoparticles-reduced graphene oxide based electrochemical immunosensor for the cardiac biomarker myoglobin
No full textA composite consisting of gold nanoparticles and reduced graphene oxide (AuNPs@rGO) was electrochemically prepared in-situ on a screen printed electrode (SPE) which then was used as an immunosensor for the cardiac biomarker myoglobin. The nanocomposite was characterized by transmission electron microscopy (TEM, scanning electron microscopy (SEM), atomic force microscopy, FTIR and electrochemical impedance spectroscopy. For FTIR, TEM and SEM, the deposition was done on indium tin oxide coated glass plates. The immunosensor was obtained by immobilization of in-house generated antibody against cardiac myoglobin on the electrode surface. The immunosensing response was monitored using differential pulse voltammetry, which showed a reduction peak at ~ −0.5 V (vs. Ag/AgCl). The reduction peak arises from the reduction of iron moiety present in the heme group of myoglobin. The immunosensor exhibited dynamic linearity range from 1 ng.mL−1 to 1400 ng.mL−1 with the detection limit of ~0.67 ng.mL−1 for cardiac myoglobin. The obtained result was almost eight times better (in terms of detection limit) than that obtained with ELISA tests (with detection limit of ~4 ng.mL−1) using the same antibodies. The immunosensor was applied to analyze spiked serum samples also
Solution processed simple and scalable graphene patterning method for nanodevices application
No full textWe have reported a simple, scalable and solution processed graphene patterning method using electron beam lithography followed by a lift-off process. This method is free from etching process and can be used for fabrication of graphene based patterns for nanodevices application. This process is universal to arbitrary substrates and can be employed for large scale pattern fabrication especially for graphene array based nanodevice applications. Using this method various types of graphene patterns like rectangular lines (100 μm × 10 μm) connecting with square pads (50 μm × 50 μm) and hall probe patterns were created over oxidized silicon substrates
Recent Advances in Cardiac Troponin I Based Sensors for Detection of Human Heart Attack
No full textCardiovascular disease (CVD) is considered as a major life threat in human globally, and with time more
sophisticated technique for estimating and therapeutics is still desirable. There has been rising attention in detection of diagnostic biomarker for cardiac injury to predict risk of heart attack. Cardiac troponin I (cTnI) has established to be a convincing biomarker for acute myocardial infarction (AMI) detection. An immunoassay and aptamer based biosensors for cTnI can play a significant role in diagnosis of AMI. Over the past decades, several approaches concerning cTnI detection have been investigated, including colorimetric, fluorescence, electrochemical, surface plasmon resonance and paramagnetic. This review focussed more on recent methodologies about surface immobilized detection of cTnI