This study investigates the effect of magnetic nanoparticles(NPs) on the weakly polar nematic liquid crystal(NLC).Different parameters of dielectric data were measured for both the homeotropic and planar aligned sampl...This study investigates the effect of magnetic nanoparticles(NPs) on the weakly polar nematic liquid crystal(NLC).Different parameters of dielectric data were measured for both the homeotropic and planar aligned samples as a function of frequency and temperature and the substantial changes have been noticed for the doped systems. Dielectric permittivity has been increased after the dispersion of magnetic NPs in the pure NLC. Dielectric anisotropy has also been influenced by incorporating the magnetic NPs with the NLC molecules. These results were attributed to the dipole–dipole interaction between the magnetic nanoparticles and nematic liquid crystal molecules. Electro-optical study indicated the faster rise time and fall time of the doped systems as compare to pure NLC. Threshold voltage has been calculated and found to be decreased for the doped systems. Moreover, we have also calculated the rotational viscosity and the splay elastic constant for pure and the doped systems. Both the rotational viscosity and splay elastic constant of the doped systems are found to be considerably lower than those of pure NLC. Change in these properties has been explained on the basis of molecular disturbances created by the interaction between the magnetic nanoparticle and LC director. This study reveals that the inclusion of magnetic NPs in weakly polar NLC can be useful to enhance the basic properties of the weakly polar NLC and make it a promising material for many display applications.展开更多
Ayurvedic and other alternative medical practi-tioners throughout the world have been using pulse diagnosis to detect disease and the organ at distress by feeling the palpations at three close yet precise positions of...Ayurvedic and other alternative medical practi-tioners throughout the world have been using pulse diagnosis to detect disease and the organ at distress by feeling the palpations at three close yet precise positions of the radial artery. This paper presents a robust electro-mechanical system, ‘Nadi Yantra’ which uses piezoelectric based pressure sensors to capture the signals from the radial artery. Morphology of the waveforms obtained from our system concurs with standard physiological arterial signals. Reproducibility and stability of the system has been verified. Signal processing techniques were applied to obtain features such as amplitude, power spectral density, bandpower and spectral centroid to reflect variations in signals from the three channels. Further, wavelet based techniques were used to process the pressure signals and percussion peaks were identified. The interval between the percussion peaks was used to calculate Heart Rate Varibility (HRV), a useful tool for assessing the status of the autonomic nervous system of the human body non-invasively. Time domain indices were calculated from direct measurement of peak-peak (PP) intervals and from differences between the PP intervals. Frequency domain indices such as very low frequency (VLF) power, low frequency (LF) power, high frequency (HF) power, LF/HF ratio were also calculated. Thereafter, nonlinear Poincare analysis was carried out. A map of consecutive PP intervals was fitted to an ellipse using least squares method. Results from 7 datasets are depicted in this paper. A novel pressure pulse recording instrument is deve loped for the objective assessment of the ancient sci-ence of pulse diagnosis. The features calculated using multi resolution wavelet analysis show potential in the evaluation of the autonomic nervous system of the human body.展开更多
An image consists of large data and requires more space in the memory. The large data results in more transmission time from transmitter to receiver. The time consumption can be reduced by using data compression techn...An image consists of large data and requires more space in the memory. The large data results in more transmission time from transmitter to receiver. The time consumption can be reduced by using data compression techniques. In this technique, it is possible to eliminate the redundant data contained in an image. The compressed image requires less memory space and less time to transmit in the form of information from transmitter to receiver. Artificial neural net- work with feed forward back propagation technique can be used for image compression. In this paper, the Bipolar Coding Technique is proposed and implemented for image compression and obtained the better results as compared to Principal Component Analysis (PCA) technique. However, the LM algorithm is also proposed and implemented which can acts as a powerful technique for image compression. It is observed that the Bipolar Coding and LM algorithm suits the best for image compression and processing applications.展开更多
Thyroid abnormalities have been reported in persons with HIV infection, although data have been inconsistent with respect to its frequency and association with specific medications. The purpose of this study was to ex...Thyroid abnormalities have been reported in persons with HIV infection, although data have been inconsistent with respect to its frequency and association with specific medications. The purpose of this study was to explore thyroid system response to thyroid releasing hormone stimulation in persons with and without HIV infection and determine the extent to which their response was associated with depression. As part of a larger study of neuroendocrine response persons with HIV-1 infection, control and HIV-1 infected individuals were evaluated. Participants' response to TRH stimulation was evaluated via TSH, total T3, and T4 levels at baseline and 15, 30, 45, and 60 minutes after TRH stimulation. Participants with HIV infection had a more robust response to TRH stimulation as measured by higher levels of TSH, lower levels of T4 and modestly higher levels of T3. Depressed persons had a reduced TSH response to stimulation and lower levels of both T4 and T3, although the effect of depression on T4 was not statistically significant. These results suggest that TSH response to TRH-stimulation may be exaggerated in individuals with HIV infection but reduced in those with depression. They also suggest that the effects of depression and HIV infection may interact, and may provide a partial explanation for observed thyroid abnormalities in HIV-infected individuals. Results thus provide a partial explanation for findings on thyroid and depression in those affected by HIV infection.展开更多
The effective delivery of drugs to the targeted tissues or cells has always been a cause of concern.Nanotechnology has emerged as an effective tool to solve this problem of targeted drug delivery.The development of na...The effective delivery of drugs to the targeted tissues or cells has always been a cause of concern.Nanotechnology has emerged as an effective tool to solve this problem of targeted drug delivery.The development of nanoparticle drug delivery systems is a revolutionary step in the healthcare domain.Nanoparticles loaded with drugs,known as nanomedicines,are used to achieve site-specific delivery of drugs that reduces the amount of required dose and,hence,toxicity.The nanoparticles,due to their small sizes,can easily cross the cell barriers.Also,the surface of the nanoparticles can be modified in such a way that it can be recognized by the molecules on the targeted cells.The addition of ligands,antibodies,aptamers,etc.,is done to modify the surface.Therefore,these nanoparticle drug delivery systems are used to obtain targeted delivery of drugs,controlled delivery,biocompatibility,low toxicity and degradation within acceptable time period.The novel drug delivery techniques involving nanoparticles are designed to improve the pharmacological and therapeutic properties of drugs.Nowadays,metallic as well as biodegradable nanoparticles are used as effective drug carriers for cancer,cardiovascular diseases,brain related disorders and so on.Metallic nanoparticles are obtained by the reduction of metallic ions from their solutions to the nano-size range.Of the metallic nanoparticles,Gold is studied very extensively due to its inert nature and relatively high biocompatibility than other metals.Biodegradable nanoparticles are synthesized from polymeric substances such as polylactic acid(PLA),gelatin,chitosan,etc.Some other examples of nanoparticles are dendrimers,liposomes,carbon-based,viral based,etc.展开更多
文摘This study investigates the effect of magnetic nanoparticles(NPs) on the weakly polar nematic liquid crystal(NLC).Different parameters of dielectric data were measured for both the homeotropic and planar aligned samples as a function of frequency and temperature and the substantial changes have been noticed for the doped systems. Dielectric permittivity has been increased after the dispersion of magnetic NPs in the pure NLC. Dielectric anisotropy has also been influenced by incorporating the magnetic NPs with the NLC molecules. These results were attributed to the dipole–dipole interaction between the magnetic nanoparticles and nematic liquid crystal molecules. Electro-optical study indicated the faster rise time and fall time of the doped systems as compare to pure NLC. Threshold voltage has been calculated and found to be decreased for the doped systems. Moreover, we have also calculated the rotational viscosity and the splay elastic constant for pure and the doped systems. Both the rotational viscosity and splay elastic constant of the doped systems are found to be considerably lower than those of pure NLC. Change in these properties has been explained on the basis of molecular disturbances created by the interaction between the magnetic nanoparticle and LC director. This study reveals that the inclusion of magnetic NPs in weakly polar NLC can be useful to enhance the basic properties of the weakly polar NLC and make it a promising material for many display applications.
文摘Ayurvedic and other alternative medical practi-tioners throughout the world have been using pulse diagnosis to detect disease and the organ at distress by feeling the palpations at three close yet precise positions of the radial artery. This paper presents a robust electro-mechanical system, ‘Nadi Yantra’ which uses piezoelectric based pressure sensors to capture the signals from the radial artery. Morphology of the waveforms obtained from our system concurs with standard physiological arterial signals. Reproducibility and stability of the system has been verified. Signal processing techniques were applied to obtain features such as amplitude, power spectral density, bandpower and spectral centroid to reflect variations in signals from the three channels. Further, wavelet based techniques were used to process the pressure signals and percussion peaks were identified. The interval between the percussion peaks was used to calculate Heart Rate Varibility (HRV), a useful tool for assessing the status of the autonomic nervous system of the human body non-invasively. Time domain indices were calculated from direct measurement of peak-peak (PP) intervals and from differences between the PP intervals. Frequency domain indices such as very low frequency (VLF) power, low frequency (LF) power, high frequency (HF) power, LF/HF ratio were also calculated. Thereafter, nonlinear Poincare analysis was carried out. A map of consecutive PP intervals was fitted to an ellipse using least squares method. Results from 7 datasets are depicted in this paper. A novel pressure pulse recording instrument is deve loped for the objective assessment of the ancient sci-ence of pulse diagnosis. The features calculated using multi resolution wavelet analysis show potential in the evaluation of the autonomic nervous system of the human body.
文摘An image consists of large data and requires more space in the memory. The large data results in more transmission time from transmitter to receiver. The time consumption can be reduced by using data compression techniques. In this technique, it is possible to eliminate the redundant data contained in an image. The compressed image requires less memory space and less time to transmit in the form of information from transmitter to receiver. Artificial neural net- work with feed forward back propagation technique can be used for image compression. In this paper, the Bipolar Coding Technique is proposed and implemented for image compression and obtained the better results as compared to Principal Component Analysis (PCA) technique. However, the LM algorithm is also proposed and implemented which can acts as a powerful technique for image compression. It is observed that the Bipolar Coding and LM algorithm suits the best for image compression and processing applications.
文摘Thyroid abnormalities have been reported in persons with HIV infection, although data have been inconsistent with respect to its frequency and association with specific medications. The purpose of this study was to explore thyroid system response to thyroid releasing hormone stimulation in persons with and without HIV infection and determine the extent to which their response was associated with depression. As part of a larger study of neuroendocrine response persons with HIV-1 infection, control and HIV-1 infected individuals were evaluated. Participants' response to TRH stimulation was evaluated via TSH, total T3, and T4 levels at baseline and 15, 30, 45, and 60 minutes after TRH stimulation. Participants with HIV infection had a more robust response to TRH stimulation as measured by higher levels of TSH, lower levels of T4 and modestly higher levels of T3. Depressed persons had a reduced TSH response to stimulation and lower levels of both T4 and T3, although the effect of depression on T4 was not statistically significant. These results suggest that TSH response to TRH-stimulation may be exaggerated in individuals with HIV infection but reduced in those with depression. They also suggest that the effects of depression and HIV infection may interact, and may provide a partial explanation for observed thyroid abnormalities in HIV-infected individuals. Results thus provide a partial explanation for findings on thyroid and depression in those affected by HIV infection.
文摘The effective delivery of drugs to the targeted tissues or cells has always been a cause of concern.Nanotechnology has emerged as an effective tool to solve this problem of targeted drug delivery.The development of nanoparticle drug delivery systems is a revolutionary step in the healthcare domain.Nanoparticles loaded with drugs,known as nanomedicines,are used to achieve site-specific delivery of drugs that reduces the amount of required dose and,hence,toxicity.The nanoparticles,due to their small sizes,can easily cross the cell barriers.Also,the surface of the nanoparticles can be modified in such a way that it can be recognized by the molecules on the targeted cells.The addition of ligands,antibodies,aptamers,etc.,is done to modify the surface.Therefore,these nanoparticle drug delivery systems are used to obtain targeted delivery of drugs,controlled delivery,biocompatibility,low toxicity and degradation within acceptable time period.The novel drug delivery techniques involving nanoparticles are designed to improve the pharmacological and therapeutic properties of drugs.Nowadays,metallic as well as biodegradable nanoparticles are used as effective drug carriers for cancer,cardiovascular diseases,brain related disorders and so on.Metallic nanoparticles are obtained by the reduction of metallic ions from their solutions to the nano-size range.Of the metallic nanoparticles,Gold is studied very extensively due to its inert nature and relatively high biocompatibility than other metals.Biodegradable nanoparticles are synthesized from polymeric substances such as polylactic acid(PLA),gelatin,chitosan,etc.Some other examples of nanoparticles are dendrimers,liposomes,carbon-based,viral based,etc.
