5 research outputs found
Determining level of PCBs in skin and muscle tissue of Cyprinus carpio and Esox lucius in Anzali Wetland (Abkenar)
The aim of this research is to determine the levels of polycholoro biphenil (PCBs) in skin and muscle tissues of common carp (Cyprinus carpio) and common pike (Esox lucius) fishes in the west part of Anzali wetland (Abkenar) in the two seasons, autumn 2009 and winter 2010. In each seasons, nine fishes from each species were selected randomly. The samples, transferred in cool condition and the muscles and skins of them were removed. All of the preparations organs clean up and PCBS analysis were carried with GC-ECD (Gas chromatography). Mean concentrations of PCBS were 24.36пg/g dry.w in skin 14.36пg/g dry.w in muscle tissue for E. lucius and 21.84пg/g dry.w in skin and 20.86пg/g dry.w in muscle tissue of C. carpio. In the autumn, the values was less than FDI standard and food standard Australia/AZ MRL and skin tissue of E. lucius and muscle tissue of C. carpio was over of US EPA standard values. Mean concentration of PCBS were 29.43пg/g dry.w in skin and 10.10ng/g dry.w in muscle tissue for E. lucius and 33.06пg/g dry.w in skin and 11.00пg/g dry.w in muscle tissue for C. carpio. In the winter, the value was less than FDI standard and food standard Australia /AZ MRL and skin tissue of E. lucius and skin tissue of C. carpio was over of US EPA standard values. Mean concentration of PCBs in water in the autumn (0.0042ppb) was less than recommended water quality Criteria E.P.A and in the winter (0.1938ppb) was over recommended water quality Criteria E.P.A. Mean concentration of PCBs in sediment in the autumn (4.89ng/g dry.w) and winter (4.48ng/g dry.w) was less than Interim Canadian Sediment Quality Guidelines. There were significant differences between E. lucius mussels and C. carpio skin tissue in two seasons (autumn and winter) in water and ingredient suspension. But in sediments, no significant difference was detected in autumn and winter
Primary Central Nervous System Lymphoma
ObjectivePrimary central nervous system lymphoma (PCNSL) is an extremely rare condition in childhood. We report the first case of PCNSL in a child in Iran.Clinical presentationA nine-year-old boy was referred to Mofid Hospital with the history of headache of four months and seizure of 2 months duration. Magnetic resonance imaging of the brain revealed a hyper-intense lesion in left fronto-parietal area with secondary satellite lesions. Biopsy of the brain mass was performed. Pathologic findings showed brain lymphoma and immunohistochemistry confirmed this diagnosis. The treatment started with intrathecal and systemic chemotherapy in combination with radiotherapy
Liquid supercoiling
Supercoiling is the large-scale secondary coiling or buckling of a structure that is already coiled at a smaller scale. Here, we show experimentally that a fluidmechanical analog of supercoiling can occur when a thin "rope" of viscous fluid falls vertically from a great height onto a surface. For appropriate values of the viscosity ν, the flow rate Q, and the fall height H, a primary coiling instability of the rope forms a hollow coiled cylinder that then experiences a secondary buckling instability in the form of periodic folding accompanied by slow rotation of the folding plane. To delineate the conditions under which this supercoiling state appears, we carry out systematic laboratory experiments over wide ranges of Q and H using several fluids with different viscosities. We find that five different states of the rope are possible: supercoiling (SC), periodic collapse of the fluid cylinder formed by a primary coiling instability (PC), periodic folding (F), and steady coiling (C) of the rope itself, and axisymmetric stagnation flow(S). Up to three of these states can be realized for a given set of experimental conditions, and we determine detailed state diagrams showing which combinations are observed as a function of ν, Q, and H. The selection of the states is controlled by the dimensionless parameter gHQ2/ν4 (g is the gravitational acceleration), which is directly related to the ratio of the rope radius a to the coil radius R in steady primary coiling with the parameters ν, Q, and H.</p