621 research outputs found

    Analysis of the GOES 6.7 micrometer channel observations during FIRE 2

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    Clouds form in moist environments. FIRE Phase II Cirrus Implementation Plan (August, 1990) noted the need for mesoscale measurements of upper tropospheric water vapor content. These measurements are needed for initializing and verifying numerical weather prediction models and for describing the environment in which cirrus clouds develop and dissipate. Various instruments where deployed to measure the water vapor amounts of the upper troposphere during FIRE II (e.g. Raman lidar, CLASS sonds and new cryogenic frost hygrometer on-board aircraft). The formation, maintenance and dissipation of cirrus clouds involve the time variation of the water budget of the upper troposphere. The GOES 6.7 mu m radiance observations are sensitive to the upper tropospheric relative humidity, and therefore proved extremely valuable in planning aircraft missions during the field phase of FIRE II. Warm 6.7 mu m equivalent black body temperatures indicate a relatively dry upper troposphere and were associated with regions generally free of cirrus clouds. Regions that were colder, implying more moisture was available may or may not have had cirrus clouds present. Animation of a time sequence of 6.7 mu m images was particularly useful in planning various FIRE missions. The 6.7 mu m observations can also be very valuable in the verification of model simulations and describing the upper tropospheric synoptic conditions. A quantitative analysis of the 6.7 mu m measurement is required to successfully incorporate these satellite observations into describing the upper tropospheric water vapor budget. Recently, Soden and Bretherton (1993) have proposed a method of deriving an upper tropospheric humidity based on observations from the GOES 6.7 mu m observations. The method is summarized in the next section. In their paper they compare their retrieval method to radiance simulations. Observations were also compared to ECMWF model output to assess the model performance. The FIRE experiment provides a unique opportunity to further verify the GOES upper tropospheric relative humidity retrieval scheme by providing (1) aircraft observations to cross-validate the calibration of the GOES 6.7 mu m channel, (2) accurate upper tropospheric water vapor concentrations for verification, and (3) veritical variability of upper tropospheric water vapor

    Ocean water vapor and cloud liquid water trends from 1992 to 2005 TOPEX Microwave Radiometer data

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    The continuous 1992–2005 data set of the TOPEX Microwave Radiometer (TMR) has been reprocessed to provide global, zonal, and regional scale histories of overocean integrated water vapor (IWV) and cloud liquid water (CLW). Results indicate well-defined trends in IWV on global and hemisphere scales, with values of 1.8 ± 0.4%/decade (60°S–60°N), 2.4 ± 0.4%/decade (0–60°N), and 1.0 ± 0.5%/decade (0–60°S). The uncertainties represent 1 standard deviation of the regressed slope parameter adjusted for lag 1 autocorrelation. These results are comparable to earlier results based on analyses of the multiinstrument SSM/I ocean measurements beginning in 1988. For the 1992–2005 interval, comparisons between SSM/I- and TMR-derived IWV trends show remarkable agreement, with global trends differing by less than 0.3%/decade, comparable to the statistical uncertainty level and about one-sixth of the global TMR-derived trend. Latitudinal and regional analyses of IWV trends show large variability about the global mean, with synoptic scale variations of IWV trends ranging from ∼−8 to +8%/decade. Averaged over 5° latitude bands the IWV trends reveal a near zero minimum in the Southern Tropical Pacific and maximum values of ∼4%/decade over the 30–40N latitude band. Comparisons with band latitude averaged SST data over the same 1992–2005 interval roughly match a delta_IWV/delta_SST trend scaling of ∼11%/K, consistent with previously observed tropical and midlatitude seasonal variability. TMR-derived CLW trends are fractionally comparable to the IWV trends. The CLW values are 1.5 ± 0.6%/decade (60°S–60°N), 2.0 ± 0.8%/decade (0–60°N), and 1.1 ± 0.8%/decade (0–60°S). When scaled to global mean CLW derived from SSM/I and compared seasonally, the TMR CLW variations exhibit excellent tracking with the SSM/I results. Unlike IWV, however, the CLW statistical uncertainties do not likely reflect the dominant error component in the retrieved trends. The 1992–2005 CLW trend estimates were particularly sensitive to short-term trends in the first and last 2 years of the TMR archive. Additional errors difficult to quantify include strong aliasing effects from precipitation cells and uncertainties in the radiative transfer models utilized in the generation of the TMR CLW algorithm

    Combination of electroporation delivered metabolic modulators with low-dose chemotherapy in osteosarcoma

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    Background: Osteosarcoma accounts for roughly 60% of all malignant bone tumors in children and young adults. The five-year survival rate for localized tumors after surgery and chemotherapy is approximately 70% whilst it drastically reduces to 15–30% in metastatic cases. Metabolic modulation is known to increase sensitivity of cancers to chemotherapy. A novel treatment strategy in Osteosarcoma is needed to battle this devastating malady. Results: Electroporation-delivered metabolic modulators were more effective in halting the cell cycle of Osteosarcoma cells and this negatively affects their ability to recover and proliferate, as shown in colony formation assays. Electroporation-delivered metabolic modulators increase the sensitivity of Osteosarcoma cells to chemotherapy and this combination reduces their survivability. Conclusion: This novel treatment approach highlights the efficacy of electroporation in the delivery of metabolic modulators in Osteosarcoma cells, and increased sensitivity to chemotherapy allowing for a lower dose to be therapeutic. Methods: Metabolic modulations of two Osteosarcoma cell lines were performed with clinically available modulators delivered using electroporation, and its combination with low-dose Cisplatin. The effects of Dicholoroacetic acid, 2-Deoxy-D-glucose and Metformin on cell cycle and recovery of Osteosarcoma cells were assessed. Their sensitivity to chemotherapy was also assessed when treated in combination with electroporation-delivered metabolic modulators

    Expressional changes in stemness markers post electrochemotherapy in pancreatic cancer cells

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    Pancreatic cancer is one of the most lethal cancers with high metastatic potential and strong chemoresistance. The capability of a tumor to grow and propagate is dependent on a small subset of cells within a tumor, termed cancer stem cells. Cancer stem cells exhibit great tumorigenicity and are closely correlated with drug resistance and tumor recurrence. The aim of our study was to illustrate electrochemotherapy as an effective treatment for pancreatic cancer along with the expression change in stemness genes (Nanog, Sox2 and Oct3/4) in pancreatic cancer cells post electrochemotherapy with bleomycin, cisplatin and oxaliplatin. Our results showed the enhanced expression of Nanog and decreased expression level of Oct3/4 after electrochemotherpy. We thus propose that these stemness markerS may have important roles in the initiation and/or recurrence of pancreatic cancer, and consequently may serve as important molecular diagnostics and/or therapeutic targets for the development of novel treatment strategies in pancreatic cancer patients. In conclusion, targeting these stemness factors could potentially improve electrochemotherapy as a treatment and preventing recurrence

    Statin associated necrotizing autoimmune myopathies in the Indigenous population: a case series from North Queensland

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    Aim: To describe clinical and histopathological features of statin associated necrotizing autoimmune myopathies (NAM) in Indigenous Australians and increase awareness of this condition amongst treating physicians. Methods: Cases were collected through the Rheumatology Department at The Townsville Hospital between March 2012 and January 2015. A chart review was performed to obtain retrospective information about each case. We detail patient demographics, presenting features, histopathological findings, autoimmune profile, treatment and outcomes. Results: 4 Indigenous Australians were identified as having a biopsy confirmed statin associated NAM. All patients had been on atorvastatin for at least 2 years and had significant proximal weakness with average CK level on presentation 16,820 U/L. Predisposing factors for myopathy included vitamin D deficiency and diabetes mellitus (all cases), with primary hypothyroidism and liver cirrhosis identified in two other cases. Two individuals were positive for the auto-antibody anti-HMGCR. Histopathological findings included muscle necrosis with varying degrees of inflammation, membrane attack complex (MAC) deposition and MHC-1 upregulation. Treatment involved various combinations of prednisolone, IVIG, methotrexate and mycophenolate. Recovery was slow but favourable in all cases with an average length of inpatient stay of 54 days. There was a significant delay in diagnosis of 1–3 months in two of the cases. Conclusions: The statin associated necrotizing autoimmune myopathies are rare but important disorders that cause significant morbidity to affected individuals. Given the prevalence of cardiovascular disease in Indigenous Australians, further research is required to facilitate earlier diagnosis and improved treatment outcomes

    Statin associated necrotizing autoimmune myopathies in the Indigenous population: a case series from North Queensland

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    Aim: To describe clinical and histopathological features of statin associated necrotizing autoimmune myopathies (NAM) in Indigenous Australians and increase awareness of this condition amongst treating physicians. Methods: Cases were collected through the Rheumatology Department at The Townsville Hospital between March 2012 and January 2015. A chart review was performed to obtain retrospective information about each case. We detail patient demographics, presenting features, histopathological findings, autoimmune profile, treatment and outcomes. Results: 4 Indigenous Australians were identified as having a biopsy confirmed statin associated NAM. All patients had been on atorvastatin for at least 2 years and had significant proximal weakness with average CK level on presentation 16,820 U/L. Predisposing factors for myopathy included vitamin D deficiency and diabetes mellitus (all cases), with primary hypothyroidism and liver cirrhosis identified in two other cases. Two individuals were positive for the auto-antibody anti-HMGCR. Histopathological findings included muscle necrosis with varying degrees of inflammation, membrane attack complex (MAC) deposition and MHC-1 upregulation. Treatment involved various combinations of prednisolone, IVIG, methotrexate and mycophenolate. Recovery was slow but favourable in all cases with an average length of inpatient stay of 54 days. There was a significant delay in diagnosis of 1–3 months in two of the cases. Conclusions: The statin associated necrotizing autoimmune myopathies are rare but important disorders that cause significant morbidity to affected individuals. Given the prevalence of cardiovascular disease in Indigenous Australians, further research is required to facilitate earlier diagnosis and improved treatment outcomes
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