Temporal and spatial variations in percentage cover of macroalgae on rocky shores in South of Caspian Sea (Astara to Babolsar)

The most important primary producers of rocky shores are macroalgae. The present study investigated the temporal–spatial changes, the percentage of coverage and the influence of abiotic factors on macroalgae on rocky shores of southern Caspian Sea. Ten sampling stations were selected in the natural and artificial rocky shores from Astara to Babolsar. Sampling lasted for one year and took place every 2 months from September 2013 to July 2014 using a 50×50 quadrate sampler. Epibenthic macroalgae consisted of 2 genus, Cladophora and Entromorpha, from green algae and one genus, Laurenica, from red algae. The average water temperature, salinity, pH, dissolved oxygen and water conductivity were 16.48 °C, 9.87ppt, 8.27, 9.89 mg/l and 16.52 m/s, respectively. According to the results, the maximum algal coverage was observed in September (70.50 %) and the minimum coverage was observed in January (21.50 %). Results of one-way ANOVA indicated that the mean of algal coverage in various months of the year were significantly different (P<0.05). One-way ANOSIM ecosystem similarity test indicated that the coverage rates of the stations were homologous and similar. The results also showed that temperature has a significant effect on macroalgae coverage ratio on rocky shores in the southern Caspian Sea

Study of fish meal substitution with earthworm in diet of rainbow trout (Oncorhynchus mykiss)

This experiment was carried out to evaluate the effect of earthworm (Eisenia fetida) in diet for rainbow trout in a complete randomized design with 5 treatments in triplicates using 15 cages in a pound for 8 weeks. Ten fish with average weight 120 g was stocked in each replication. The earthworm (as fed) at the levels of 0, 25, 50, 75 and 100% was replaced with fish meal in rainbow trout diet. Results showed that feed intake decreased significantly (P b0.05). The chemical composition analysis of fish meat showed that there were no significant effects between control and 25% and 50% earthworm in diet for dry matter, crude protein and ash, but fat content significantly decreased as earthworm increased (P < 0.05). This present study showed that the earthworm (Eisenia fetida) can be used in rainbow trout diet up to 50% instead of fish meal

A comparison between gastroesophagheal ultrasonography vs. barium swallow in determining the pattern of gastroesophageal reflux in a pediatric population

Background: Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal pathology in infants and young children. Ultrasonography (US) has been considered to be a reliable diagnostic tool for GERD but the severity of GERD and the clinical implications based on imaging findings has not been evaluated. Aims: To compare the diagnostic value of lower esophageal US with that of barium swallow in demonstrating the severity of GERD. Materials and methods: Fifty one pediatric patients, age between 1 month to 12 years, 34 male and 17 female with clinical suspicion of GERD were included. The patients were initially submitted to barium swallow (BS) and subsequently to transabdominal US. During BS, the number of gastroesophageal reflux episodes was documented in a 5-minute period. Transabdominal US documented the number and duration of reflux episodes during a 5-minute period, the angle of His, mucosal thickness, and intraabdominal esophageal length (IAEL). Results: Duration and number of reflux episodes in US were significantly higher in patients that had severe gastroesophageal refluxes at BS. At US the cutoff point of 9.5 seconds (sensitivity 80, specificity 60) for reflux duration and more than 2 episodes in 5 minute ultrasound study (sensitivity 75, specificity 58) were defined to correlate with severe gastroesophageal reflux at BS.The angle of His, the esophageal wall mucosal thickness, and the IAEL did not correlate with the severity of GERD detected in BS. Conclusion: US can predict the severity of GERD. Therefore, except in the case of specific patients in whom mechanical causes are suspected to be responsible for GERD, BS can be replaced by US

Nonlinear actuation of micromechanical Casimir oscillators with topological insulator materials toward chaotic motion:Sensitivity on magnetization and dielectric properties

We have investigated the dynamical actuation of micro-electromechanical systems under the influence of attractive and repulsive Casimir forces between topological insulator plates as a function of their dielectric function and coating magnetization. The analysis of the Casimir force in the limit of strong and weak magnetization shows that the attractive force, which is produced for plate magnetizations in the same direction, is greater than the repulsive force that is produced for opposite magnetizations. However, both forces remain comparable for intermediate magnetizations. Moreover, for weak magnetization, the attractive force becomes stronger for an increasing dielectric function, while the opposite occurs for the repulsive force. On the other hand, increasing magnetization decreases the influence of the dielectric function on both the repulsive and attractive forces. Furthermore, for conservative systems, bifurcation and phase portrait analysis revealed that increasing magnetization decreases the regime of stable operation for devices with attractive forces, while their operation remains always stable under the presence of repulsive forces. Finally, for non-conservative periodically driven systems, the Melnikov function and Poincaré portrait analysis show that for magnetizations in the same direction leading to strong attractive Casimir forces, chaotic motion toward stiction is highly likely to occur preventing the long-term prediction of actuating dynamics. A remedy for this situation is obtained by the application of any magnetization in opposite directions between the interacting surfaces since the repulsive force makes it possible to prevent stiction

Assessment of outer hair cell function and blood antioxidant status of rabbits exposed to noise and metal welding fumes

Objectives: To investigate the interaction between welding fumes and noise in causation of hearing impairment. Methods: Groups of rabbits (n = 6) were exposed to noise, welding fumes or combination of both prior to Distortion Product Otoacoustic-Emissions (DPOAEs) analysis. The function of outer hair cells (OHCs) was examined by DPOAE assessment over a broad range of frequencies. Variations in DPOAE amplitude were compared between control (n = 6) and exposed (n = 18) groups. Results: The DPOAEs levels measured at different frequencies (1379-6299 Hz) were found to decrease significantly (P &lt; 0.05) in rabbits exposed to 110 dB sound pressure level (SPL) broadband noise (8 h/day, 12 days). In rabbits, exposed to carbon-steel welding fumes alone (157 mg/m3), the threshold shift was limited to the high frequencies (2759-6299 Hz), whereas, mixed exposure to noise and fumes resulted in reduction of DPOAEs at all the frequencies. Changes in DPOAEs were associated with increased susceptibility of erythrocytes to oxidation (P &lt; 0.05). Exposure to noise or fumes alone or simultaneously, suppressed total antioxidant ability of plasma as measured by ferric reducing ability of plasma (FRAP). Noise alone or in combination with fumes resulted in depletion of blood glutathione (GSH). Despite suppression of FRAP in the exposed groups, GSH was found to remain unchanged due to welding fumes suggesting that antioxidants other than GSH are affected by toxicants present in metal welding fumes. Conclusion: Exposure to very high levels of welding fumes can increase noise-related effects on OHC function by extending hearing threshold shift to wide band frequencies. © 2006 Elsevier Ireland Ltd. All rights reserved

Squamous cell carcinoma (SCC) arising in esophageal colon interposition

The idea of using the colon to replace a resected esophagus has a long history. The colon has become a favored organ for esophageal reconstruction in adults with esophageal cancer when the stomach is not suitable or is unavailable. In this article, we introduce an 84-year-old woman that she had surgery 40 years ago and presented with an invasive well differentiated squamous cell carcinoma of colonic origin in reconstructed esophagus. © 2017 The Author

Surface topography evolution and fatigue fracture of polysilicon

This paper presents the results of an experimental stydy of the micromechanisms of fatigue crack nucleation and fatigue fracture in polysilicon MEMS Structures. The initial stages of fatigue are shown to be associated with stress-assisted surface topography evolution and the thickening of SiO 2 layers that form on the unpassivated polysilicon surfaces and crack/notch faces. The differences in surface topography and oxide thickness are elucidated as functions of fatigue cycling before discussing the micromechanisms of crack growth and final fracture.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44773/1/10853_2004_Article_5252917.pd

A study of the oxidation-induced conformational and functional changes in neuroserpin

Background: Neuroserpin, a member of the Serine Proteinase Inhibitor (Serpin) superfamily, is known to be a neuroprotective factor in the focal ischemic stroke followed by reducing the microglial activation. Neuroserpin is a protein rich of methionine residues that can scavenge the free radical species which may increase its neuroprotective effect. On the other hand, the oxidative modifications of the amino acid residues in neuroserpin may lead to changes in its conformation and function. In this study, it was investigated the changes in the conformation and the function of the oxidized neuroserpin. Methods: Neuroserpin expressed in E. coli, BL21 or M15 harboring plasmid pQE81L containing neuroserpin cDNA. Expressed neuroserpin was purified by resin sulfopropyl A50 precharged with 0.1 M NiSO4 under denaturing condition. Neuroserpin was oxidized under oxidative stress condition in the presence of different concentration of hydrogen peroxide. The oxidation of neuroserpin was conveniently detected by a carbonyl content assay using 2, 4 dinitrophenylhydrazine. Changes in tertiary structure of neuroserpin were monitored by spectrofluorimeter to study the alteration of intrinsic fluorescence and also fluorescence of 8-anilinonaphthalin-1 sulfonic acid (ANS) in native and oxidized form of neuroserpin. Results: Total expressed neuroserpin was estimated 4-5 mg/lit in 2XYT culture media. SDS-PAGE analysis of purified neuroserpin showed a single band which reflects the efficiency of the resin SP A50 for purification of the proteins containing 6xHis tag. Carbonyl content of oxidized and native neuroserpin was estimated 12.3 ± 0.3 and 0.45 ± 0.05, respectively. The inhibitory activity of oxidized neuroserpin decreased up to 40-60 as compared with native form of neuroserpin. Intrinsic fluorescence and also the emission of ANS bind to the hydrophobic region of the protein altered from 380 to 85 and in the case of ANS from 105 to 150 in oxidized and native form of neuroserpin, respectively. Conclusion: The decreased intrinsic fluorescence intensity, an enhancement in the fluorescence of ANS, and loss of the inhibitory activity up to 40-60 in neuroserpin, all suggested a conformational modification in the protein under the oxidative stress condition. Remaining the inhibitory activity of neuroserpin reflects that the protein tolerates the oxidative stress condition effectively