50 research outputs found
Natural bioactive compounds and antimicrobial potential of Pavetta indica L.
Terrestrial plants have opened up a new perspective for pharmaceutical research and development of novel antimicrobial agents for the treatment of microbial diseases. Therefore, it is necessary to start an urgent need to screen the plants for novel bioactive compounds. In this context, present study was carried out to screen phytochemical constituents from leaves of Pavetta indica L., and its antimicrobial potential. P. indica leaves possess Chlorophyll a (1.21 ±0.05 mg g-1), Chlorophyll b (1.61 ±0.09 mg g-1), total chlorophyll (2.82 ±0.13 mg g-1), carotenoids (0.57 ±0.06 mg g-1), total soluble sugars (30.08 ±0.79 mg g-1), total soluble starch (13.54 ± 0.72), total soluble proteins (47.81 ± 2.82 mg g-1), total free amino acids (5.77 ± 0.69 mg g-1), total phenol (7.67 ± 0.72 mg g-1), hydroxyl phenols (5.74 ± 0.29 mg g-1) and lipids (53.53 ± 2.50 mg g-1) while alkaloids, tannins, steroids, phenolic compounds, saponins, triterpenoids and cardiac glycosides were also present in the leaves of P. indica. Absolute ethanolic extract of P. indica showed significant antimicrobial activity against all the tested pathogens, followed by aqueous extract. In concluded that, P. indica leaves crude extracts have wide range of bioactive compounds and which might be led to potential antimicrobial activity. They may lend to developing novel therapeutic agent to different infectious diseases.</jats:p
Detection of Turner syndrome using hand X-ray using anchor based links segmentation method
Turner Syndrome (TS) is a chromosomal disorder, wherein the female’s growth is impacted. Immature ovaries, low stature, and heart abnormalities are a range of developmental and medical issues due to TS. The condition of TS might be detected prior to birth, throughout infancy or in the early years of life. The diagnosis of TS in girls with modest symptoms and indications is sometimes deferred until they reach adolescence or become young adults. This study presents an algorithm to segment the hand digital X-ray image in children with TS. In medical image and computer vision examination, image segmentation is demanding, and very crucial. Prevailing segmentation algorithms even now suffer from common segmentation issues including under-segmentation, over-segmentation, and spurious or non-closed edges, regardless of the several years of studies. In this paper, Anchor Based Link (ABL) segmentation approach is proposed to detect TS based on fourth Metacarpal bone from left hand X-ray images. The detection of TS is demonstrated based upon the comparison of proposed approach with existing watershed segmentation and Gaussian-Mixture-Model-based Hidden-Markov-Random-Field (GMM-HMRF) method. The proposed approach attains better segmentation based on the ratio of height and width of left fourth finger that is analyzed for normal children and children having TS with the help of edge pixel present in the metacarpal bone that has been segmented. The suggested method is verified on fifty (50) sample X-ray hand images of carpal bones, providing 0.60 ± 0.02 as an average Dice coefficient. </jats:p
Effect of pouring temperature on cast Al/SiCp and Al/TiB2 metal matrix composites
AbstractThe effect of pouring temperatures of an ex situ (Al/SiCp) and in situ (Al/TiB2) metal matrix composites (MMCs) synthesized using stir casting method were studied. The Al/SiCp composite were fabricated by mixing of 6wt.% of SiCp into cast A356 aluminium alloy melt and poured at diverse pouring temperatures (730∘C, 750∘C and 770∘C). The Al/TiB2 MMCs were obtained by melting A356 aluminium alloy and mixing of KBF4 and K2TiF6 precursor salts whose stoichiometric ratio composition corresponds to 6wt.% of TiB2 reinforcement and other parameters were constant (stirring speed 300 RPM and holding time 30 minutes). The composite melt was poured into the permanent mould with varied pouring temperatures (800∘C, 820∘C and 840∘C). Coarser and homogenous SiC particles were presented in the Al/SiCp MMCs, whereas, finer and uniformly distributed TiB2 particles were appeared at the MMCs of Al/TiB2. The mechanical properties viz. tensile strength, fracture toughness and hardness of Al/SiCp and Al/TiB2 MMCs were experimentally determined as per the ASTM standards and compared. Higher tensile and fracture strength were occurred at the MMCs of Al/TiB2 as compared to Al/SiCp MMCs and base alloy of aluminium as well. Maximum hardness was attained at the pouring temperatures of 820∘C and 750∘C in the MMCs of Al/ TiB2 and Al/SiCp, respectively.</jats:p
Surface roughness and microstructure analysis on drilling of titanium diboride in-situ aluminium metal matrix composite
Abstract
Aluminium and its alloys are widely used for fabricating components are used in aircraft, automobile, defence and structural applications. Due to its light weight and high strength, it is applied in the various commercial purposes such as window, doors, construction member etc. However, machining of aluminium alloys using conventional machining methods is difficult. In this present investigation, an endeavour has been made to drill TiB2
in situ aluminium metal matrix composite alloy developed using stir casting method. During the casting two different salts namely K2TiF6 and KBF4 are added with matrix materials to form TiB2. The paper is studied the surface roughness (SR) of drilled TiB2
in situ aluminium metal matrix composite viz speed, feed rate and TiB2 addition. Empirical relationship is developed for SR in order to identify the dominating factors. The percentage contribution of SR is 96.35% that showed the empirical model is adequate. The normal probability plot showed the points of residuals are equally distributed over the straight line. The lack of fit value was 3.65 which is less than the standard point. Therefore, the SR model is satisfactory. SR increased with increasing of speed, feed rate and addition of TiB2. The removal of TiB2 particles causes small pits and voids due to the inclusion of reinforcement. The minimum SR was achieved at lowest speed (1260 rpm), feed rate (0.05 mm rev−1) and TiB2 addition (2%). As speed and feed increased, the surface hardness increased.</jats:p
Effect of pouring temperature on cast Al/SiCp and Al/TiB2 metal matrix composites
The effect of pouring temperatures of an ex situ (Al/SiCp) and in situ (Al/TiB2) metal matrix composites (MMCs) synthesized using stir casting method were studied. The Al/SiCp composite were fabricated by mixing of 6wt.% of SiCp into cast A356 aluminium alloy melt and poured at diverse pouring temperatures (730∘C, 750∘C and 770∘C). The Al/TiB2 MMCs were obtained by melting A356 aluminium alloy and mixing of KBF4 and K2TiF6 precursor salts whose stoichiometric ratio composition corresponds to 6wt.% of TiB2 reinforcement and other parameters were constant (stirring speed 300 RPM and holding time 30 minutes). The composite melt was poured into the permanent mould with varied pouring temperatures (800∘C, 820∘C and 840∘C). Coarser and homogenous SiC particles were presented in the Al/SiCp MMCs, whereas, finer and uniformly distributed TiB2 particles were appeared at the MMCs of Al/TiB2. The mechanical properties viz. tensile strength, fracture toughness and hardness of Al/SiCp and Al/TiB2 MMCs were experimentally determined as per the ASTM standards and compared. Higher tensile and fracture strength were occurred at the MMCs of Al/TiB2 as compared to Al/SiCp MMCs and base alloy of aluminium as well. Maximum hardness was attained at the pouring temperatures of 820∘C and 750∘C in the MMCs of Al/ TiB2 and Al/SiCp, respectively
Effect of Ceramic Particulate Addition on Aluminium Based Ex-Situ and In-Situ Formed Metal Matrix Composites
Screening of wild plant species for antibacterial activity and phytochemical analysis of Tragia involucrata L.
AbstractEight wild plant species namely Tragia involucrata L., Cleistanthus collinus (Roxb.)Benth. Ex Hook.f., Sphaeranthus indicus L., Vicoa indica (L.) Dc., Allmania nodiflora (L.) R.Br. ex wight., Habenaria elliptica Wight., Eriocaulon thwaitesii Koern. and Evolvulus alsinoides L. were used for phytochemical extraction with four different solvents. Antibacterial activity of these plants was studied against Escherichia coli NCIM 2065 using Kirby Bauer agar disc diffusion assay. Effective antibacterial activity was shown by T. involucrata acetone extract (27.3mm), compared to standard medicinal drug amoxicillin (28.3mm). Minimum inhibitory concentration (MIC) of T. involucrata extract was 15mg/mL and hence, it could be pursued further for obtaining phytomedicine. Biochemical constituents of T. involucrata fresh leaf were: sugars (55mg/g), starch (0.7182mg/g), proteins (0.0166mg/g) and lipids (170mg/g). Alkaloids, tannins, phenolic compounds, flavonoids and steroids were also observed qualitatively
