74 research outputs found
On χs-Orthogonal Matrices
In this paper we, introduced the concept of χs-orthogonal matrices and extended some results of Abaraetal, [3] in the context of secondary transpose
Alzheimer’s And Parkinson’s Disease Classification Using Deep Learning Based On MRI: A Review
Neurodegenerative disorders present a current challenge for accurate diagnosis and for providing precise prognostic information. Alzheimer’s disease (AD) and Parkinson's disease (PD), may take several years to obtain a definitive diagnosis. Due to the increased aging population in developed countries, neurodegenerative diseases such as AD and PD have become more prevalent and thus new technologies and more accurate tests are needed to improve and accelerate the diagnostic procedure in the early stages of these diseases. Deep learning has shown significant promise in computer-assisted AD and PD diagnosis based on MRI with the widespread use of artificial intelligence in the medical domain. This article analyses and evaluates the effectiveness of existing Deep learning (DL)-based approaches to identify neurological illnesses using MRI data obtained using various modalities, including functional and structural MRI. Several current research issues are identified toward the conclusion, along with several potential future study directions
Evaluation of the Flexural Strength of Heat Polymerized Poly (Methyl Methacrylate) Denture Resin Reinforced With Fibres: An In Vitro Study
INTRODUCTION:
Synthetic resins are employed in a variety of dental and medical applications such as contact and intraocular lens, bone cements in orthopaedics, filler for bone cavities and skull defects, vertebrae stabilization in osteoporosis patients, dentures, cavity filling, sealants, maxillofacial
reconstructive materials, impression materials, orthodontic appliances, equipment etc. Among the synthetic resins, poly methyl-methacrylate is considered as the most suitable biomaterial due to its favourable properties such as biocompatibility, chemical inertness, dimensional stability, ease in
processing and other such advantages. However, PMMA based restorations cannot withstand higher rate of loading due to the inferior flexural strength. Therefore, the present study aimed to improve the flexural strength of conventional PMMA.
AIM OF THE STUDY:
The aim of this in - vitro study is to compare the flexural strength of conventional heat polymerized PMMA resin with that of glass fibres, carbon fibres, and polypropylene fibres reinforced heat cure acrylic resin.
Null Hypothesis: Reinforcement using glass fibres, carbon fibres, polypropylene fibres to improve the mechanical properties of PMMA.
Alternate Hypothesis: Reinforcement with glass fibres, carbon fibres, and polypropylene fibres did not affect the mechanical properties of PMMA.
MATERIALS:
Heat activated acrylic resin considered as the matrix material for the present study obtained from DPI (Dental products of India) was in powder – liquid from. Glass fibres, carbon fibres, polypropylene fibres are used for reinforcement. Other materials used for the preparation of the mould for the fabrication of the acrylic samples include polyvinylsiloxane impression
material, Type II gypsum products, Modelling wax for the preparation of the wax pattern, cold mould seal as the separating medium.
METHOD:
Preparation of gypsum molds to obtain the acrylic specimen: Wax pattern (65 mm x 10 mm x 3 mm) is prepared using modelling wax and invested in the dental flask in the conventional manner using model plaster. After 1 hour, the invested flask kept for dewaxing, and then any wax residue removed by washing the mould by hot water and then cleaned using soap solution,
allowed to dry. The mold is then ready to be used for the preparation of acrylic specimen.
Preparation of PMMA resin specimen: The test specimens are made with dimensions of 65 mm x 10 mm x 3mm as per the ISO 1567 standards. This enables the specimen to be tested for flexural strength on Instron Universal Testing Machine.
A total of 80 specimens are fabricated for the study, which are divided into four groups (Group 1, 2, 3 & 4) of 20 specimens each. Group 1 (control) comprised of unreinforced PMMA resin specimens; Group 2 comprised of glass fibre reinforced PMMA resin specimens, Group 3 comprised of Polypropylene fibres reinforced PMMA resin specimens, Group 4 comprised
of carbon fibre reinforced PMMA resin specimens.
Measurement of Flexural strength: All the prepared samples are tested for flexural strength using universal testing machine. Specimens are placed in a position where its two edges supported from the lower side and the load was given in the middle of the specimen from an upper side. Specimen dimension was measured and recorded into the computer.
RESULTS:
After data collection, the mean and the standard deviation (SD) values of transverse strength of each group were analysed statistically with one- way ANOVA analysis. Then significant differences between the mean of the test groups were determined by Turkey’s post hoc test using SPSS V22 software.
CONCLUSIONS:
For the fabrication of denture base PMMA resin is the material of choice for usage. Because of poor transverse, impact, and flexural strength of PMMA fracture of the base may occur. So in this study I analysed increase in flexural strength after incorporation of fibres
Effect of hydrochloric acid treated neetle fibre on oil absorbency
332-337Hydrochloric acid (HCl) treatment on nettle fibres has been performed to improve the oil absorbency. Box-Behnken experimental design is used to study the influence of parameters, such as treatment time, treatment temperature and concentration on oil absorbency. It is observed that the maximum oil absorbency of 15.39 g/g of nettle fibres is achieved at 2 % of HCl concentration, 75°C of treatment temperature and 60 min of treatment time. Scanning electron microscopic study reveals that the raw nettle fibre surface exhibits waxy and protruding parts, and on HCl treatment the surface becomes rougher. The influence of other parameters such as stirring speed, environmental temperature and reusability on oil absorbency is also studied. Oil sorbed nettle fibres are also subjected to soil burial tests and burning tests. In conclusion, the raw nettle fibres only show an oil absorbency of 9.25 (g/g), whereas HCl treated nettle fibres show a maximum oil absorbency of 15.39 g/g
Effect of hydrochloric acid treated neetle fibre on oil absorbency
Hydrochloric acid (HCl) treatment on nettle fibres has been performed to improve the oil absorbency. Box-Behnken experimental design is used to study the influence of parameters, such as treatment time, treatment temperature and concentration on oil absorbency. It is observed that the maximum oil absorbency of 15.39 g/g of nettle fibres is achieved at 2 % of HCl concentration, 75°C of treatment temperature and 60 min of treatment time. Scanning electron microscopic study reveals that the raw nettle fibre surface exhibits waxy and protruding parts, and on HCl treatment the surface becomes rougher. The influence of other parameters such as stirring speed, environmental temperature and reusability on oil absorbency is also studied. Oil sorbed nettle fibres are also subjected to soil burial tests and burning tests. In conclusion, the raw nettle fibres only show an oil absorbency of 9.25 (g/g), whereas HCl treated nettle fibres show a maximum oil absorbency of 15.39 g/g.
Quantitative differences in intestinal Faecalibacterium prausnitzii in obese Indian children
Gut bacteria contribute to energy conservation in man through their ability to ferment unabsorbed carbohydrate. The present
study examined the composition of predominant faecal microbiota in obese and non-obese children. The participants (n 28) aged 11-14
years provided fresh faecal samples and completed a dietary survey consisting of 24 h diet recall and a FFQ of commonly used foods
taken over the previous 3 months. Faecal bacteria were quantitated by real-time PCR using primers targeted at 16S rDNA. Of the
participants, fifteen (seven female) were obese, with median BMI-for-age at the 99th percentile (range 97 to<99) while thirteen
participants (seven female) were normal weight, with median BMI-for age being at the 50th percentile (range 1-85). Consumption of
energy, carbohydrates, fat and protein was not significantly different between the obese and non-obese participants. There was no
significant difference between the two groups in faecal levels of Bacteroides-Prevotella, Bifidobacterium species, Lactobacillus
acidophilus group or Eubacterium rectale. Levels of Faecalibacterium prausnitzii were significantly higher in obese children than in
non-obese participants (P = 0.0253). We concluded that the finding of increased numbers of F. prausnitzii in the faeces of obese
children in south India adds to the growing information on alterations in faecal microbiota in obesity
Prompt emission polarimetry of Gamma Ray Bursts with ASTROSAT CZT-Imager
X-ray and Gamma-ray polarization measurements of the prompt emission of
Gamma-ray bursts (GRBs) are believed to be extremely important for testing
various models of GRBs. So far, the available measurements of hard X-ray
polarization of GRB prompt emission have not significantly constrained the GRB
models, particularly because of the difficulty of measuring polarization in
these bands. The CZT Imager (CZTI) onboard {\em AstroSat} is primarily an X-ray
spectroscopic instrument that also works as a wide angle GRB monitor due to the
transparency of its support structure above 100 keV. It also has experimentally
verified polarization measurement capability in the 100 300 keV energy
range and thus provides a unique opportunity to attempt spectro-polarimetric
studies of GRBs. Here we present the polarization data for the brightest 11
GRBs detected by CZTI during its first year of operation. Among these, 5 GRBs
show polarization signatures with 3, and 1 GRB shows
2 detection significance. We place upper limits for the remaining 5
GRBs. We provide details of the various tests performed to validate our
polarization measurements. While it is difficult yet to discriminate between
various emission models with the current sample alone, the large number of
polarization measurements CZTI expects to gather in its minimum lifetime of
five years should help to significantly improve our understanding of the prompt
emission.Comment: Accepted for Publication in ApJ ; a figure has been update
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