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Specification of the frictional resistance values of tankers is the first step in managing their fuel consumption. Drag force of a very large crude oil carrier has been calculated using the numerical simulation method. With application of the ANSYS CFX software, the scaled model of the mentioned tanker with the length of 2.74 meters, width of 0.5 meters, draft of 0.17 meters was used for numerical simulation of the drag force in the tanker. Furthermore, the numerical solution of the drag force of the model was performed for 5 different speeds ranging from 0.65 to 0.85m/s. Based on the validations carried out, with mean drafts of 8 and 16.5cm, the difference between the results of the experimental and numerical models at low speeds was about 7%. However, the difference was observed to be up to 15% at higher Froude numbers. The results of the present study with respect to the SALINA are based on the method presented in ISO 19030 standard addressing the performance monitoring during vessel servicing. [ABSTRACT FROM AUTHOR]

In this paper, applications of a numerical model on simulation of two and three-dimensional flows are presented. This model solves Navier-Stokes equations using finite volume method and large eddy simulation (LES) in a collocated mesh. Artificial c ompressibility method with d ual t ime stepping is used to solve the time dependent equations. Also a modified m omentum i nterpolation method (MIM) based on the unsteady flows is deployed to overcome the non-physical pressure oscillation. Capability of the presented numerical code for flow s imulation, is a ssessed by a pplication f or two-dimensional square and three-dimensional lid-driven cavity flows. Numerical results of cavity flow presents very good agreement with the numerical and experimental data of other existent researches. [ABSTRACT FROM AUTHOR]

When a structure is placed on an erodible bed, it causes an increase in local sediment transport capacity and consequently this leads to scour in the vicinity of the structure. This is referred to as local scour in the literature. Local scour has been identified as one of the key factors that cause failure of structures in the bridges, Jetties and offshore platforms. The complexities of bridge scour mechanism have caused the scour is to be one of the most active topics in civil engineering researches. Numerous studies have been reported on local scour around bridge piers in steady currents in the last decades. A majority of these studies deal with laboratory model studies. A brief literature review can reveal the importance of this subject. Several methods have been proposed by researchers to control the scour around the bridge piers. These methods can be divided in two main categories: the first is the armoring method or increasing the resistant of the bed material around the pier as rip rap, and altering of the flow pattern around the pier is the next one. The combined effect of some tools has been studied in recent years. Using just one bed erosion controlling tool does not appear to be adequate in many cases according to conclusions of these studies. On the other hand, combining different tools could not always lead to gain better results than using a single one of these tools. In this paper, the test results of 12 combined bridge pier models to reduce the maximum score depth in clear-water condition have been presented. Experimental models are respectively: (1) berm and semiconical piers, (2) combination of berm and semi-conical piers with variable diameter in the bed, (3) combination of berm and semi-conical piers with fixed diameter in the bed, and (4) combination of third group with trapezoidal centered slot. Significant decrease (up to 46 percent) in scour depth was observed in berm pier with respect to the cylindrical reference pier. This decrease was also observed in semi-conical pier but it was much lower than the berm pier. In the second group, semi-conical combined pier with the side slope angle of 2 degrees of model piers had the least bed erosion in comparison to other two groups. In this model, the width of the berm is larger and diameter of the pier is lower in bed level. Scour depth is increased in comparison to the berm pier model in this group but it is decreased comparing to the cylindrical reference pier. Very slight decrease has been observed in the scour depth of third group model piers by fixing the pier diameter in the bed depth. Hence, increasing the pier diameter in the bed level has intensified the bed erosion in the semi-conical combined piers. Applying slot in the combined piers of third group was ineffective in increasing the protective role of model piers in the fourth group. Therefore, it can be concluded that the effect of berm model pier in decreasing scour depth was far more than other piers and combining different countermeasures for the bed erosion could not have positive influence on decreasing the scour depth in all the cases. The comparison of maximum scour depth has been conducted in all models in relative to cylindrical reference and berm pier. [ABSTRACT FROM AUTHOR]

Background: Endoscopic sinus surgery (ESS) is one of the procedures which need a clear surgical field. The purpose of this study was to compare the effects of propofol and isoflurane on depth of anaesthesia and blood loss during ESS. Materials and Methods: In this clinical trial study, 52 (36 males and 16 females) ESS candidates referred to the Shafa hospital in Kerman. One group received propofol and another group isoflurane. Mean arterial blood pressure (MAP), depth of anaesthesia (DA) and total blood loss were recorded for patients in both groups. Results: DA was decreased in both groups, but no significant correlation was observed between the two groups in DA, MAP and blood loss. Moreover, no significant difference was observed between the two groups in total blood loss. Blood pressure was decreased in both groups during surgery. Conclusion: There is no significant difference between propofol and isoflurane in DA and decreasing blood loss during ESS. Therefore, we suggest the use of hypotensive anaesthetic agents during ESS. [ABSTRACT FROM AUTHOR]

Cancer is one of the major causes of death in the world and despite many years of research, the treatment of cancer is still a problem. Epidemiological observations and laboratory studies have indicated anticarcinogenic potential of garlic, which has been traditionally used for various human diseases around the world. In this study the cytotoxicity of garlic extract against three malignant cancer cell lines including gastric (AGS), breast (MCF-7) and colon (HT-29) and a nonmalignant cell line (L929) were evaluated by the MTT assay. The results of this study reveal MCF-7 and AGS cells were sensitive to garlic extract. Despite a many reports on inhibitory effects of garlic on cancer cell line, our data showed these effects are tumor specific and dose dependent. Further studies on animal models and humans are needed to clarify the important molecules and their mechanisms.

Cutaneous cancers are among the most common forms of cancer. Melanoma is an aggressive malignancy which is poor in prognosis. Despite of many years of researches, the treatment of melanoma is still a problem. Historically, plants have been main resources in traditional medicine and natural products are considered as important sources of antitumor drugs. Meanwhile, garlic for a long time has been used in man's food as a medicinal plant. In this study, the garlic extract was prepared and fractionated by ultra-filtration method with Amicon system. Garlic extract and its fractions including residue (R) 100, R50, R30, R10, R5, and filtrate (F) 5 were investigated for their cytotoxic activities on Sk-mel3 cell line of melanoma. The results show that garlic extract induced a significant cytotoxic activity on Sk-mel3 cell line. Among fractions R100 and R10 have more potential in cytotoxic activities against Sk-mel3 melanoma cells. In conclusion, garlic appears to be a good candidate as an antitumor agent against melanoma. To clarify the effective molecules and their mechanisms more studies should be applied on animal models and humans.

Macrophages play an essential role against invading pathogen and malignancies. The present study addresses the in vivo effect of P.florida extract on nitric oxide (NO) production and cell viability of macrophages. Forty Balb/c mice were divided to 8 groups and were treated with different doses of P. florida aqueous extract. MTT test has been performed in order to evaluate viability of intraperitoneal macrophages and Griess method to measure NO production of macrophages. The results indicated that cell viability of macrophages significantly increased by oral administration of P. florida with 200, 500 and 1000mg/kg/day. Also, NO production significantly increased by oral administration of doses of 500 and 1000mg/kg/day of P. florida. but i.p. injection of P. florida with 10,20,50,100mg/kg/day significantly decreased NO production by macrophages. This study showed a macrophage activator function for P. florida and also may confirms its anti inflammatory role. Further studies are needed to address effective phytochemicals of this edible mushroom and their mechanisms.

Of 231 children with nephrotic syndrome, 87% were steroid sensitive and 13% steroid resistant. Of patients with steroid sensitive nephrotic syndrome, 38.8% were non-relapsers, 34.8% frequent relapsers and 26.4% infrequent relapsers. Among those with steroid resistant nephrotic syndrome, 37.5% had focal segmental glomerulosclerosis with a high mortality rate of 44%