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Aims: Considered as one of the marine resources and due to their effective compounds, cyanobacteria activate the cell death process in cancer cells and, thus, may be used as a new source. The aim of the current research was to evaluate the effect of oscillatoria cyanobacterium extract on breast cancer cell line and NM23 gene expression.
Materials and Methods: In the present experimental study, oscillatoria cyanobacterium was cultured in a negative zayander medium at 26°C to 28°C with a light intensity of 350 to 3500lux, under 12-hour lighting and 12-hour darkness, and the MCF-7 cell line was prepared. Breast cancer cells were treated by hydroalcoholic extracts of oscillatoria with different concentrations. The effect of extract on cell survival was evaluated by MTT assay and the effect of the extract on the changes of NM23 gene expression was investigated by Real-Time PCR.
Findings: The morphology of MCF-7 cell line showed that the oscillatoria cyanobacterium extract significantly altered the treated cells compared with control cells. The survival of cells decreased with increasing concentration, and there was a significant difference compared to the control sample. After 24 hours, the extract inhibited 50% cell survival at a concentration of 0.6mg/ml (p<0.001). The NM23 gene expression significantly increased over a 24-hour period compared with the control sample.

Conclusion: Oscillatoria Cyanobacterium extract decreases the breast cancer cell line and increases the NM23 gene expression.

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A total of 136,250 monthly test day milk records collected from 13,625 Iranian Holstein heifers (three times a day milking) calved between 1991 and 2001 and distributed over 264 herds were used to study the effects of some environmental factors influencing lacta-tion curve parameters as well as production characteristics. Wilmink’s function (Yt = W0 + W1t + W2e-0.05t) was fitted to individual lactations. Least squares analysis of variance in-dicated that the herd, year and month of calving had a significant effect on all traits under consideration. Correlation analysis showed that the parameter W0 had a negative and significant (p<0.05) relationship with parameters W1 and W2 while it was positively sig-nificantly correlated with milk at peak time and 305-day milk yield. Simple linear regres-sion analysis of adjusted means of a 305-day milk yield, days to reach peak yield as well as peak milk yield in the first year of calving also revealed that there was a phenotypic in-crease of 137.152 Kg, 0.535 day and 0.434 Kg per year, respectively.

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Previous investigation has been shown that there are several sample preparation method to model the sand or silty sand behaviors. Methods like Dry Funnel Deposition (DFD), Water Sedimentation (WS), Slurry Deposition (SD), Water Pluviation (WP), Moist Tamping (MT) and Air Pluviation (AP) are some of the mentioned methods. Each method may be useful to model the behavior of some special deposited soils. For example, DFD is the best method to model the natural deposition of silty sands, while the WS method is suitable for modeling the sands natural deposition in the rivers. MT method is the best method to simulate the behavior of compacted embankments while SD method is suitable to prevent the segregation of particles in respect to other methods like Water Pluviation. Effect of sample preparation methods on the sands and silty sands behavior is investigated to some extent, while the clayey sands are rarely investigated. In order to investigate about the effect of sample preparation method and also clay content on the behavior of sands, some specimens were prepared using air pluviation and moist tamping method and tested under undrain consolidated condition using a monotonic triaxial device. To have uniform specimens with good repetition in sample preparation, a new sample preparation device using air pluviation method was invented by the authors. Specimens of clean and clayey sand mixtures were prepared using different drop height and flow rates. The dry unit weight of all specimens was increased with increase of drop height, while increase of flow rate leads to the decrease of dry unit weight. Also, some specimens were prepared using moist tamping method in order to compare the results. A modified Ladd technique was applied to have the uniform specimens in the moist tamping method. In modified Ladd technique (Under compaction method), the initial layers are compacted with lower density, while they reach the desired density during the taping of the upper layers. This method prevents the more compacted lower layers, which is usually occurred in the usual moist tamping method. Based on the results, it was concluded that the air pluviated specimens usually behave in strain hardening manner with dilative properties, while moist tamped specimens tends to behave in strain softening manner. In addition, some valuable results are presented about the variation of liquefaction potential. It was seen that the steady state line of sand mixed with 10 percent clay is lower than the steady state line of clean sand in the e-Lnp’ plan, which is the sign of more liquefaction potential in clayey sand mixture. Also, the internal friction angle was found to be lower in clayey sand mixture in respect to clean sand. The interpretation of the results shows that two interaction manner can be distinguished between sand and clay particles; one of them is easy slippage between sand particles due to locating clay particles between them and the other is increasing the friction and cohesion between sand particles due to plasticity of clay particles. The latter will decrease the slippage between sand particles. Effect of each interaction is investigated separately using the obtained results.

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In this study effect of temperature, O₂ concentration and storage time were investigated on respiration rate of uncoated and coated pear (Dargazi Cultivar) using Sclerorhachis platyrachis essential oil of 0, 125, 250, and 500 ppm. Mathematical model using Michaelis–Menten’s equation, with the model constants described by means of an Arrhenius-type relationship was applied to predict respiration rate at various temperatures (4, 10, and 25 ºC) and O₂ concentrations to design modified atmosphere packaging (MAP) of pear in order to extend its shelf-life. Results showed that all factors affected respiration rate of the pears but the influence of temperature was most pronounced. Increase in temperature led to increase of respiration rate and reduction of positive effect of essential oil on this parameter reduction. Moreover, after about 100 hours, respiration reached equilibrium. Respiratory quotient of Pears at 4 and 10 °C was on aerobic limit. However, at 25 °C, after 110 hours, and reaching CO₂ to 23%, respiratory quotient passed the critical point. Finally, package containing 3.7% O₂ + 8.1% CO₂ + 88.2% N₂ was suggested as an appropriate MAP for storing the pears (Dargazi cultivar).
 

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Boring operations due to the large length to diameter ratio and the high flexibility of tool are prone to self-excited (chatter) vibration. This vibration may cause poor surface quality, low dimensional accuracy and tool breakage. In practice, chatter is the main limitation on production rate. The main reason of chatter phenomenon is the dynamic interaction between cutting process and structure of machine tool. By increasing the length of the cutting tool, the vibration tendency in the tool’s structure increases. Improving dynamic stiffness of the tool is the most effective solution for decreasing vibration and increasing chatter stability. For increasing the stability of the tool in long overhang boring operations, passive and active vibration control has been proposed and implemented. In active control methods, vibrations can be effectively damped over a various cutting conditions. The aim of this research is to enhance chatter stability of an industrial boring bar by increasing the dynamic stiffness. A VCA actuator is used for active vibration control. The designed setup can effectively suppress undesirable vibrations in the radial direction. First, modal parameters of the boring bar are determined by experimental modal analysis. Then, the transfer function of the actuator-tool setup is identified with the sweep frequency excitation. In the following, the direct velocity feedback is successfully implemented in the vibration control loop. The results of cutting tests indicate that the actuator has a great performance in suppressing vibrations and increasing the dynamic stiffness. Hence, the developed method can significantly increase chatter stability of boring operations.

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One of the most important constraints on manufacturing productivity is the machining vibrations. This vibrations may cause increase in machining costs, lower accuracy of products and decrease tool life. The effective solution for increasing cutting process stability and vibration suppression is to improve structural dynamic stiffness. There has been presented different techniques for enhancing dynamic stiffness of structures using passive and active vibration control methods. Although passive vibration control methods are always stable, they exhibit limited performance. In active control methods, vibrations can be effectively damped over a various conditions. The aim of this research is to enhance the dynamic stiffness of an industrial boring bar by using active damping. Cutting process mainly exposed to parameter perturbations and unknown external disturbances, therefore, designing an active vibration control system for cutting process is a challenging problem. In this research an extended state observer based control strategy was proposed that can overcome these uncertainties. The proposed strategy was implemented into an active vibration control system for a boring bar. Moreover, the direct velocity feedback is successfully implemented in the vibration control loop. The results of impact tests indicate that the control algorithms have a great performance in suppressing vibrations and increasing the structural dynamic stiffness. Voltage impact results show that ADRC controller spends less control effort than direct velocity feedback controller.

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One of the main questions in contract theory is the justification of the binding nature of contract; That why the legislator intervenes in this private field and determines some sanctions and remedies. In response to this challenge, in the common law three major theories have been offered: moral theory, economic theory and the rule of will theory. In Iranian law, legal scholars have based their theories on moral, social, economic and religious grounds. This article, while examining and evaluating these theories with an analytical-descriptive method, despite the support of most Iranian legal writers for theories based on social interests, defends the principle of autonomy of will and claims that other values can be unified with this principle. The main idea of ​​this article is that the most important and direct goal of the legislator from enforcing contracts should be to enforce the cooperative will of the parties to the contract, which is in line with supporting the higher value of autonomy. Also, efficiency as an economic value is included under autonomy and as an instrument plays a central role in formulating detailed regulations and the structure and how to support the contract.