Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 4
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

In this study, we aimed to investigate the effects of vitamin E on mouse adrenal glands in immobilization stress. Twenty-eight male, 10-week-old, BALB/C mice weighing 30-45 grams were divided into four groups. Mice were placed in a cage where no movement was allowed 6 hours/day for 7 days for immobilization stress. 10 ml/kg vitamin E was administered orogastrically 1 hour before immobilization stress in the vitamin E and stress+vitamin E group. At the end of the 7th day, all the animals were subjected to elevated-plus maze (anxiety) and forced swimming (depression) tests. Left adrenal glands were dissected for routine paraffin tissue embedding protocol. Adrenal sections were stained with hematoxylin-eosin and Azan. Malonaldehyde (MDA) levels were also measured in the adrenal tissues. Anxiety level (0.023), depression level (p=0.042) and MDA values (p=0.01) were significantly increased in the stress group. Histological sections of the stress group showed cortical atrophy, medullary hypertrophy, vascular dilation and hemorrhage. Azan staining revealed a thinned capsule and corticomedullary fibrosis in the stress group. Pathologies induced by immobilization stress were mostly reversed after vitamin E administration. The results suggested that vitamin E alleviates adverse effects of immobilization stress (oxidative, behavioral and histopathologic changes) in mice.
Go to article

Authors and Affiliations

F. Aşır
1
Y. Nergiz
1
A. Pala
1

  1. Department of Histology and Embryology, School of Medicine, Dicle University, Diyarbakır, Turkey
Download PDF Download RIS Download Bibtex

Abstract

The versatile application of titanium alloy in the aerospace industry and it’s hard to machine characteristics focus towards the additive manufacturing. The Ti-6Al-4V alloy is manufactured using the electron beam source with a novel method of prepositioned titanium alloy wires. The tribology of the additive manufactured titanium alloy under dry sliding condition is experimented and analysed using Taguchi technique. The targeted objective of minimum tribological responses are attained with the identified optimal parameters as load – 9.81 N, sliding velocity – 3 m/s, sliding distance – 3000 m for minimum specific wear rate and load – 9.81 N, sliding velocity – 3 m/s, sliding distance – 1000 m for minimum coefficient of friction. Among the parameters tested, load is found to be the dominant factor on the tribology of additively manufactured titanium alloy. The morphological analysis on the worn surface and debris revealed the existence of abrasion, delamination and adhesion wear mechanisms. The increase in the load dominantly showed the appearance of delamination mechanism.
Go to article

Authors and Affiliations

A. Manjunath
1
ORCID: ORCID
V. Anandakrishnan
2
ORCID: ORCID
S. Ramachandra
1
ORCID: ORCID
K. Parthiban
1
ORCID: ORCID
S. Sathish
3
ORCID: ORCID

  1. Gas Turbine Research Establishment, Defence Research & Development Organization, Bangalore, Karnataka-560093, India
  2. Department of Production Engineering, National Institute of Technology Tiruchirapalli, Tiruchirappalli – 620015, Tamil Nadu, India
  3. Department of Mechatronics Engineering, K.S. Rangasamy College of Technology, Tiruchengode, Namakkal – 637215, Tamil Nadu, India
Download PDF Download RIS Download Bibtex

Abstract

Source/filter models have frequently been used to model sound production of the vocal apparatus and musical instruments. Beginning in 1968, in an effort to measure the transfer function (i.e., transmission response or filter characteristic) of a trombone while being played by expert musicians, sound pressure signals from the mouthpiece and the trombone bell output were recorded in an anechoic room and then subjected to harmonic spectrum analysis. Output/input ratios of the signals’ harmonic amplitudes plotted vs. harmonic frequency then became points on the trombone’s transfer function. The first such recordings were made on analog 1/4 inch stereo magnetic tape. In 2000 digital recordings of trombone mouthpiece and anechoic output signals were made that provide a more accurate measurement of the trombone filter characteristic. Results show that the filter is a high-pass type with a cutoff frequency around 1000 Hz. Whereas the characteristic below cutoff is quite stable, above cutoff it is extremely variable, depending on level. In addition, measurements made using a swept-sine-wave system in 1972 verified the high-pass behavior, but they also showed a series of resonances whose minima correspond to the harmonic frequencies which occur under performance conditions. For frequencies below cutoff the two types of measurements corresponded well, but above cutoff there was a considerable difference. The general effect is that output harmonics above cutoff are greater than would be expected from linear filter theory, and this effect becomes stronger as input pressure increases. In the 1990s and early 2000s this nonlinear effect was verified by theory and measurements which showed that nonlinear propagation takes place in the trombone, causing a wave steepening effect at high amplitudes, thus increasing the relative strengths of the upper harmonics.

Go to article

Authors and Affiliations

James W. Beauchamp

This page uses 'cookies'. Learn more