ABSTRACT
PURPOSE: Quality Control (QC) of the Positron Emission Tomography-Computed Tomography (PET-CT) system must be performed prior to the PET-CT acquisition to ensure the reproducibility as per the manufacturer recommendation. In this study we have evaluated the performance of daily PET QC test by utilising lutetium yttrium oxyorthosilicate (LYSO) scintillation crystal natural radioactivity of 176Lu as a source of radiation to perform the PET uCare.iQC with uMI550 digital PET-CT system. This was also compared with existing radioactive external source-based QC test with other manufacturer PET-CT systems. METHOD: This radioactive source free daily QC study was performed on uMI550 digital PET-CT system. The daily QC data report was captured and interpreted. This PET-CT system has unique feature that utilises the inherent property of LYSO crystal that is 176Lu with natural radioactivity abundance of 2.6%. The Lutetium-176 (176Lu) radioactivity is used to perform the daily QC in PET in place of external radioactive source of Germanium-68 (68Ge). This feature work automatically in preschedule manner to complete the daily QC at preset time in the morning and system get ready after the QC test. RESULTS: Over 120 automatic PET daily uCare.iQC test were performed. The daily PET QC test was prescheduling setup for 6:00 am in every morning. No failure on daily QC test were observed. The QC parameters and system parameters consistency was observed. CONCLUSION: It was concluded that the daily PET QC can be performed by utilising LYSO crystal inherent natural radioactivity of 176Lu as a source of radiation to perform the test as replacement of external 68Ge radioactive source. IMPLICATION FOR PRACTICE: PET-CT daily QC by utilizing the 176Lu radioactivity of LYSO crystal results in reducing the radiation exposure to operation staff and reducing operational cost by elimination 68Ge shield source Phantom.
ABSTRACT
Two species of Trichoderma i.e. T. harzianum and T. viride have been isolated from the soil samples collected from the higher altitude (2000-3500 m) of Garhwal Himalayan region in India. The two species were grown in Petri plates on TSM agar media and it was also observed that the optimum temperature and pH for Trichoderma growth was 30 degrees C and 5.5 respectively. When incubated on TSM agar medium at 4 degrees C, the fungus grew normally with heavy induced sporulation within three weeks of incubation. Induction of sporulation on exposure to low temperature appeared to be strategies for survival of these species in extreme cold environment temperature 4 to 5 degrees C. Antifungal activities of the two species of Trichoderma were demonstrated with phytopathogenic fungi in dual cultures. The antifungal metabolites produced by Trichoderma spp., diffusible as well as volatile, caused abnormalities in pathogenic fungi. Plant growth promotion of Trichoderma spp. was also shown through plant analysis in greenhouse.
Subject(s)
Biological Control Agents , Trichoderma/growth & development , Trichoderma/metabolism , Altitude , Cladosporium/pathogenicity , Fusarium/pathogenicity , India , Plant Diseases/microbiology , Plant Roots/microbiology , Rhizoctonia/pathogenicity , Rhizosphere , Soil Microbiology , Spores, Fungal , Temperature , Trichoderma/physiology , Zea mays/microbiologyABSTRACT
Mercuric chloride, which is used as a fungicide in tropical paddy-fields, inhibits growth (in N2 , i.e. molecular nitrogen, and 5 mM KNO3 media) and heterocyst formation (in N8 medium) in the blue-green alga Nostoc muscorum at a concentration of 0.3 µg ml-1 and above. These inhibitory effects were reversed on supplementation with 3 mM exogenous glucose. A mercury resistant mutant of this alga has been obtained, which is stable through repeated cell transfers in N2 medium. It is suggested that a Hg-inducible protein/enzyme system is responsible for the intracellular mercury-resistance of this mutant.
