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The influence of tumour blood perfusion variability on thermal damage during nanoparticle-assisted thermal therapy
No full textPurpose: This study investigates the influence of blood perfusion variability within a tumour and the surrounding healthy tissue during nanoparticle-assisted thermal therapy. It seeks to define ideal therapeutic parameters for a wide range of perfusion rates to attain the desired thermal damage.
Material and methods: Pennes’ bioheat model and the Arrhenius model are used to evaluate the thermal damage for a two-dimensional tumour surrounded by healthy tissue. A wide range of tumour perfusion rates were modelled, ranging from moderate to high perfusion in both a homogenously and a heterogeneously perfused tumour. Results: For low perfusion rates, a temporal variation in blood perfusion does not critically influence the thermal damage. For moderately and highly perfused tumours, temporal variation in blood perfusion extends the thermal damage zone by 25–52% compared to a constant perfusion rate. For the tumour size and perfusion conditions under consideration, the ideal therapeutic parameters were found to be irradiation intensity of 1 W/cm2, and irradiation duration of 105–150 s, for a nanoparticle volume fraction of 0.001%.
Conclusions: It is concluded for low perfusion rates that due to shorter therapeutic duration, nanoparticle-assisted thermal therapy is relatively insensitive to changes in the perfusion rate during the therapy. For moderately and highly perfused tumours, a constant perfusion under-predicts the real thermal damage zone. This study concludes that for moderately and highly perfused tumours the spatial as well as temporal blood perfusion dynamics should be carefully accounted for to get a realistic estimate of thermal damage zone
In Vitro Cytotoxicity of Multiwalled and Single-Walled Carbon Nanotubes on Human Cell Lines
No full textCarbon nanotubes are the building blocks for future electronics, materials, health care devices etc. In order to explore the health care applications of nanotubes in diagnosis and drug delivery, it is important to understand their toxicity. In the present study the in vitro responses were seen when carbon nanotubes were exposed to human cell lines. It typically involves dispersion of multiwall and single walled carbon nanotubes, as well as carbon black and quartz as reference material within the cell culture medium followed by their subsequent addition to human cell lines. MTT 3-(4, 5 dimethylthiazol-2 yl) 2, 5-diphenyl tetrazolium bromide, a tetrazole assay was performed; cell viability was measured by observing their absorbance using ELISA (enzyme-linked immunosorbent assay) reader. Cell viabilities at different concentrations i.e. 50, 10, 5, 3, 1 μg mL−1 were studied. In MTT assay, it was observed that cell viability increases with decrease in concentration of single walled and multiwall carbon nanotubes. We found that both behave almost in the same manner in terms of viability in case of MTT assay. Cellular uptake of FITC (fluorescein isothiocyanate) labeled carbon nanotubes were imaged using confocal microscopy and transmission electron microscope
Experimental and numerical investigation of heat confinement during nanoparticle-assisted thermal therapy
No full textNanoparticle-assisted thermal ablation therapy has recently evolved as a promising future therapy for cancer treatment. This therapy is advantageous because it is potentially much more selective than traditional methods (surgery or chemotherapy) in terms of destroying cancerous cells while leaving healthy tissue intact. In this study, heat confinement and thus the healthy tissue sparing characteristics, were experimentally investigated. Two Agarose gel samples of cylindrical shape were synthesized for evaluating the heat confinement in the axial and radial directions. A specified region of the gel was embedded with gold nanoparticles which were synthesized in this study (mimicking an injection of nanoparticles to the tumor region), while the rest of the plain gel mimics the surrounding healthy tissue. These Agarose gel samples were irradiated through fiber optic and the spatiotemporal temperature response was measured. A numerical model was also developed and validated against these experiments. The measurements were then extended to real tumor-tissue by taking into account blood perfusion and metabolic heat generation. It is observed that with the proposed approach, heat can be well confined to the nanoparticle embedded region. This study shows that with a well-designed system it is possible to obtain thermal ablation of the tumor region while sparing healthy tissue 3 mm beyond the tumor boundary
Comparative evaluation of shock absorption ability of custom-fit mouthguards with new-generation polyolefin self-adapting mouthguards in three different maxillary anterior teeth alignments using Fiber Bragg Grating (FBG) sensors
No full textPrevention of orofacial injuries is one of the biggest pre-occupations in sports dentistry. The custom-fitted mouthguard is considered the best choice for fit and protection when compared to over-the-counter commercial mouthguards. However, cost and time prohibit their mass production. It is therefore imperative to have an over-the-counter true mouth-formed mouthguard with comparable properties. The present in vitro experimental study was carried out to compare the shock absorption ability of EVA laminate mouthguards with self-adapting polyolefin material mouthguards in three different anterior teeth alignments
Investigative Study of Secured Data Transfer Mechanism for Smart Grid Metering System
No full textThis paper investigates the development of network coding in NS2 platform for smart grid data logging from the nodal points in the network. It incorporates a sense
of privacy, security and originality to be verified during the process of transmitting the data from different metering nodes to the service center. The network coding procedures involves Advanced Metering Infrastructures (AMI) for data gathering by using vector
based Destination-Sequenced Distance Vector routing (DSDV) and broadcasting the same by encryption and decryption of the transmitted data with appropriate cryptographic keys based on Enhanced Security (ES) to ensure the originality of the transmitted secured
data in the chosen architecture. This investigative study emphasizes the importance of wireless network in NS2 platform to be adopted to work out the performance of the
indices to exhibit its suitability for use in the real world secured data transmission in power grid environment
Prediction of Adulteration in Honey Using Rheological Parameters
No full textHoney is a sweet substance that can be adulterated easily with inexpensive sweeteners by making syrup.
Water being the second major constituent of honey, makes its flow behavior one of the important parameter
for quality determination. In the present study, the rheological characteristics of honey samples
adulterated with different concentrations of jaggery syrup were studied using rotational rheometer with
parallel plate geometry. The viscosity of honey and adulterated honey samples was determined by varying
temperature and percentage of jaggery concentration. All the adulterated honey samples behaved as
non-Newtonian fluid. The viscosity increased linearly with increase in concentration of adulteration and
varied from 2.48–4.80 Pa s as adulteration increased from 5 to 30%. Oscillatory tests were performed
to find the possible effect of storage time on different honey samples. It was found that adulteration
decreased the shelf life of honey, thus rheology can be considered one of the important parameters to
determine adulteration of honey
Surface assembly of nano-metal organic framework on amine functionalized indium tin oxide substrate for impedimetric sensing of parathion
No full textThe present paper reports the assembly and pesticide sensing application of a nanometal organic framework [Cd(atc)(H2O)2]n (‘atc’=2-aminoterephthalic acid). The assembly of the NMOF film has been achieved by sequential dipping of a 2-aminobenzylamine (2-ABA) modified indium tin oxide (ITO) slide in organic linker ‘atc’ and metal ion ‘Cd2+’ solutions. The different structural and morphological characteristics of the NMOF thin film have been characterized. The availability of pendent –COOH functional groups on the assembled NMOF film is exploited to synthesize a pesticide immunosensor by conjugating the NMOF film with anti-parathion antibody. This immunosensor has been explored for the electrochemical impedance spectroscopy (EIS) based analysis of parathion in the concentration range of 0.1–20 ng/mL. The proposed detection is specific with respect to other organophosphate compounds, e.g. malathion, paraoxon, fenitrothion, monochrotophos and dichlorovos. The proposed sensor shows the detection limit of 0.1 ng/mL and it is applicable for analysis of parathion in a rice sample. The sensor's performance is validated by comparting the obtained results with gas chromatographic data
Scratch enhancement and measurement in periodic and non-periodic optical elements using digital holography
No full textScratch or flaw detection plays an important role in imaging optics and optical instrumentation. Even a minute scratch or crack can spoil coating and/or scatter incident light which causes irregularities/noise in the signal. Present paper describes use of digital holography for inspection of periodic and non-periodic optical elements for presence of any type of flaws like scratch, dust particles, irregularity etc. Digital image processing on numerically reconstructed wavefronts of the test samples provides enhanced image of the flaw. Various parameters of the flaws are measured. Experimental results of scratch on a glass plate and a lens and a thin hair on a grating and a mirror are presented
Effect of Particle Size on Ammonia Sensing Response of Zinc Oxide
No full textEfficient gas sensor was made with zinc oxide
nanoparticles synthesized by mechanical alloying using high energy planetary ball mill. As received and milled zinc oxide nanoparticles were characterized with X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and UV-Vis Spectroscopy techniques. Morphological study was carried out by using Transmission Electron Microscopy (TEM). The particle size of ZnO
nanoparticles was reduced from micron to nano meter range after milling for 45h. The Ammonia gas sensing response of as received and milled ZnO nanoparticles was studied from I-V characteristics plots obtained for different concentration of ammonia (50 to 600 ppm). The sensitivity of zinc oxide was observed to increase with decrease in particle size from micron to nanometer
Soil pH Sensing Techniques and Technologies A Review
No full textThis paper presents the review on different concepts of soil pH detection techniques and technologies.
Soil pH is a key parameter for crop productivity therefore its spatial variation should be adequately addressed to improve precision agriculture management system. Soil pH affects the soil's physical, chemical, and biological properties and processes, and thus plant growth. Soil pH, a measure of hydronium ion (H+) concentration traditionally tested in labs to decide how much fertilizer to apply to a field. Recently, with increased emphasis on precision agriculture, economics, and the environment, soil tests are also a logical tool to determine areas where adequate or excessive fertilization has taken place. In addition, they are used to monitor the impact of past fertility practices on
changes in a field’s nutrient status. Therefore, developing rapid tools which can detect pH variations on a site-specific basis has become pressing need of the hour because laboratory based methods are inadequate, time consuming, laborious, and expensive. From above perspective, this paper attempts to present review of existing suitable methods, deliberations on pros and cons, and a proposal for pH sensor development which could transmit data wirelessly