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Postdeposition heat treatment‐induced modifications of nanoplasmonic response in glancing angle‐deposited (GLAD) Ag nanostructures are systematically investigated. The as‐deposited GLAD Ag thin films are annealed at various temperatures namely 200, 250, 300, and 350 °C in air atmosphere. The reduction in localized surface plasmon resonance (LSPR) absorption peak width is detected with annealing. Morphological characterization of the as‐deposited and annealed films reveals reduction in grain size and shape distributions responsible for narrowing of the LSPR peak width. The refractive index sensitivities of the as‐deposited and annealed films are measured using an in‐house‐developed optical setup and figure of merit (FOM) of the sensors is also estimated. An increase in FOM of the sensors is observed upon annealing while sensitivity is found to be reduced. E‐field profile surrounding the Ag nanoparticles is also simulated to explain the experimental observations on refractive index sensitivity of the films. [ABSTRACT FROM AUTHOR]

Demodulation of vibration signal to detect faults in machinery has been a prominent prevalent technique that is discussed by a number of authors. This paper deals with the demodulation of the current signal of an induction motor driving a multistage gearbox for its fault detection. This multistage gearbox has three gear ratios, and thus, three rotating shafts and their corresponding gear mesh frequencies (GMFs). The gearbox is loaded electrically by a generator feeding an electrical resistance bank. Amplitude demodulation and frequency demodulation are applied to the current drawn by the induction motor for detecting the rotating shaft frequencies and GMFs, respectively. Discrete wavelet transform is applied to the demodulated current signal for denoising and removing the intervening neighboring features. Spectrum of a particular level, which comprises the GMFs, is used for gear fault detection. Index Terms--Current, demodulation, fault diagnosis, gears, wavelet transforms.

Background: Myopia is one of the most common causes of visual impairment worldwide.It is proved in earlier studies that the eye shape is different in myopic and nonmyopic children even at a very young age, with the former manifesting asymmetric axial globe elongation and the latter global expansion but limited information is available regarding hypermetropia. Aim: To find out the variations of axial ocular dimensions in relation to age, sex, height and to demonstrate any possible correlation of body mass index (BMI) in myopic hypermetropic and emmetropic patients. Settings: It is a cross-sectional observational study. Materials and Methods: All the patients attending eye OPD in the Regional Institute of Ophthalmology (R.I.O.), Medical College, Kolkata, West Bengal, India from June2010 to May 2011.Axial dimensions were measured by B-mode USG. Refractive status was measured.Age, gender, height and BMI were also observed. After collecting all the data,all the variables were summarised by descriptive statistics followed by correlation testing by Pearson's Correlation Coefficient r. Results: Height was positively correlated with axial length, anterior chamber depth, vitreous chamber depth ;age was positively correlated with axial length, vitreous chamber depth and negatively correlated with anterior chamber depth. Subjects with higher BMI tended to had refractions that were more hypermetropic. Conclusion: The findings of the present study can highlight not only the normal range of the different ocular parameters namely axial length, anterior chamber depth, vitreous chamber depth and lens thickness but their variation with age, gender, height and weight. [ABSTRACT FROM AUTHOR]

Introduction: Patellar height is an important parameter of patellar stability. Its importance is evident from various attempts to measure it, by different scientists from time to time and many indices have been derived among which Insall-Salvati index (IS index) is the most simple, accurate and easy to measure. In this study a new clinical method has been tried to measure patellar height by applying the same principle of IS index. Aim: To compare clinical method of measurement of IS index with the one derived radiologically and to establish the higher cut off value of the clinical method. Materials and Methods: In the present study 186 knee joints (93 subjects) were subjected to measurement of patellar height by both clinical and radiological methods. The IS index was measured bilaterally from lateral view of X-ray plates and it was measured clinically in every knee joint. Both the values were compared using students t-test and higher cut off values were set for normal knee joint for the clinical method. Results: Among 93 study participants majority were females (54.83%), age of the patients varied from 10-68 years with mean age of 28 years and Standard deviation (SD) of 16.4. It was found that, there was no statistically significant difference between the mean values obtained by clinical method of measurement, compared to conventional one (IS Index) for both the genders and age groups on both the sides. A cut off value of 0.98 cm by clinical method gives sensitivity of 80% and specificity of 36% with area under the ROC curve 0.596. Conclusion: The subjects with patellar height of less than cut off value by clinical method can avoid radiological investigation as there was no statistically significant difference of IS index between radiological and clinical methods. [ABSTRACT FROM AUTHOR]

The article reports on the proposal of the motor current signature analysis (MCSA) as an efficient and non-intrusive method of detecting fluctuation in gear load in Europe. The FFT analysis revealed that low frequencies of the vibration signatures have sidebands across line frequency of the current while high frequencies of vibration signature are difficult to be detected. The results indicate that MCSA with discrete wavelet transform can be an alternative for conventional vibration monitoring.

We have experimentally demonstrated spatially selective absorption in Ag-SiO 2 -Ag based trilayer thin films by tuning the deposition angle of SiO 2 layer. These structures generate cavity resonance which can be tuned across the substrate locations due to spatially selective thickness and refractive index of silicon oxide (SiO 2 ) film sandwiched between metallic silver (Ag) mirrors. Spatially selective property of SiO 2 film is obtained by oblique angle deposition technique using an electron beam evaporation system. The resonance wavelength of absorption in this trilayer structure shifts across the substrate locations along the direction of oblique deposition. The extent of shift in resonance increases with increase in angle of deposition of SiO 2 layer. 4.14 nm mm -1 average shift of resonance wavelength is observed when SiO 2 is deposited at 40° whereas 4.76 nm mm -1 average shift is observed when SiO 2 is deposited at 60°. We observed that the width of resonance increases with angle of deposition of the cavity layer and ultimately the resonant absorption disappears and becomes broadband when SiO 2 is deposited at glancing angle deposition (GLAD) configuration. Our study reveals that there is a suitable range of oblique angle of deposition from 40° to 60° for higher spatial tunability and resonant absorption whereas the absorption becomes broadband for glancing angle deposition., (© 2024 IOP Publishing Ltd.)

Patellar height is one of the important parameter in patellar stability. Growth spurt or excessive physical strain can lead to high-riding patella or patella alta. But this is not yet proved. This study was mainly targeted at eliciting the influence of age on Insall-Salvati index, one of the important index to measure patellar height. As the present study is meant for measuring the patellar height separately in male and female, it is also to find out the effect of gender on patellar height if any. The study was been conducted in North Bengal Medical College and Hospital among 93 subjects covering both adult and adolescent age groups. Patellar height of respective subjects was measured radiologically using Insall-Salvati Index; results were extrapolated for statistical analysis. It revealed that value of Insall-Salvati index was higher in adult compared to adolescent group but the difference was not statistically significant. Statistical tests shows no significant difference in Insall-Salvati index according to sex. While screening the athletes patella alta must be kept in mind as this can be associated with patellofemoral pain syndrome, chondromalacia patellae, knees with apophysitis of tibial tubercle (Osgood-Schiatter disease). Not only that, significant cause of recurrent patellar dislocation can be associated with patella alta