Development and testing of a novel sulfur dioxide sonde

A novel technique has been developed to measure sulfur dioxide (SO2) using a modification of the existing electrochemical concentration cell (ECC) ozonesonde technology. The current sonde-based method to measure SO2 (i.e., the dual-sonde approach) involves launching two ozonesondes together, with one of the sondes having a filter to remove SO2 at the inlet. The SO2 profile is determined by taking the difference between the measurements from the two instruments. The dual-sonde method works well in typical tropospheric conditions when [O3]&gt;[SO2] but saturates when [SO2]&gt;[O3] and has large uncertainties in the upper troposphere and lower stratosphere that would limit its effectiveness in measuring SO2 from an explosive volcanic eruption. Due to these limitations, several modifications were made to create a single-sonde system that would directly measure SO2 (i.e., the SO2 sonde). These modifications included (1) a positively biased ECC current, (2) the addition of an O3 removal filter, and (3) the addition of a sample dryer. The SO2 sonde measures SO2 as a reduction in the cell current. There was a strong correlation (r2&gt;0.94) between the SO2 sonde and a Thermo 43c analyzer during controlled laboratory tests and pre-flight tests. Varying humidity levels affected the SO2 sonde's sensitivity (avg =84.6±31.7 ppbv µA−1, 1σ RSD =37 %) during initial field tests, which was resolved by adding a sample dryer upstream of the O3 removal filter and pump inlet. This modification significantly reduced the variability and increased the sensitivity of the SO2 measurements (avg =47±5.8 ppbv µA−1, 1σ RSD =12 %). Field tests included measurements near Kīlauea volcano (before and during the 2018 eruption of the Lower East Rift Zone), Costa Rica's Turrialba volcano, and anthropogenic plumes from the Athabasca oil sands region of Alberta, Canada. This single-SO2-sonde system is an effective, inexpensive instrument for measuring both ground-based and vertical profiles of SO2 from anthropogenic and natural sources (i.e., volcanic eruptions) over a wide range of concentrations.</p

Vacuum fluctuations and topological Casimir effect in Friedmann-Robertson-Walker cosmologies with compact dimensions

We investigate the Wightman function, the vacuum expectation values of the field squared and the energy-momentum tensor for a massless scalar field with general curvature coupling parameter in spatially flat Friedmann-Robertson-Walker universes with an arbitrary number of toroidally compactified dimensions. The topological parts in the expectation values are explicitly extracted and in this way the renormalization is reduced to that for the model with trivial topology. In the limit when the comoving lengths of the compact dimensions are very short compared to the Hubble length, the topological parts coincide with those for a conformal coupling and they are related to the corresponding quantities in the flat spacetime by standard conformal transformation. In the opposite limit of large comoving lengths of the compact dimensions, in dependence of the curvature coupling parameter, two regimes are realized with monotonic or oscillatory behavior of the vacuum expectation values. In the monotonic regime and for nonconformally and nonminimally coupled fields the vacuum stresses are isotropic and the equation of state for the topological parts in the energy density and pressures is of barotropic type. In the oscillatory regime, the amplitude of the oscillations for the topological part in the expectation value of the field squared can be either decreasing or increasing with time, whereas for the energy-momentum tensor the oscillations are damping.Comment: 20 pages, 2 figure

BIOCHRONOLOGY OF SELECTED MAMMALS, MOLLUSCS AND OSTRACODS FROM THE MIDDLE PLIOCENE TO THE LATE PLEISTOCENE IN ITALY. THE STATE OF THE ART

The Authors have elaborated four range charts of mammalian (large and micro), molluscs and fresh-water and brackish ostracodes faunas, for the selected Plio-Pleistocene fossiliferous localities of the Italy. A new Mammal Age (Aurelian) correlatable to late Middle and Late Pleistocene has been defined. Inside this age two Faunal Units (Torre in Pietra and Vitinia) have been defined as characteristic for Early and Middle Aurelian, while no gisements have been chosen for the late Aurelian. Biochronological units are calibrated on magnetostratigraphic and isotopic scales and by radiometric datings.&nbsp;&nbsp; &nbsp

BIOCHRONOLOGY OF SELECTED MAMMALS, MOLLUSCS AND OSTRACODS FROM THE MIDDLE PLIOCENE TO THE LATE PLEISTOCENE IN ITALY. THE STATE OF THE ART

The Authors have elaborated four range charts of mammalian (large and micro), molluscs and fresh-water and brackish ostracodes faunas, for the selected Plio-Pleistocene fossiliferous localities of the Italy. A new Mammal Age (Aurelian) correlatable to late Middle and Late Pleistocene has been defined. Inside this age two Faunal Units (Torre in Pietra and Vitinia) have been defined as characteristic for Early and Middle Aurelian, while no gisements have been chosen for the late Aurelian. Biochronological units are calibrated on magnetostratigraphic and isotopic scales and by radiometric datings.&nbsp;&nbsp; &nbsp

The role of TG2 in regulating S100A4-mediated mammary tumour cell migration

The importance of S100A4, a Ca2+-binding protein, in mediating tumour cell migration, both intracellularly and extracellularly, is well documented. Tissue transglutaminase (TG2) a Ca2+-dependent protein crosslinking enzyme, has also been shown to enhance cell migration. Here by using the well characterised non-metastatic rat mammary R37 cells (transfected with empty vector) and highly metastatic KP1 cells (R37 cells transfected with S100A4), we demonstrate that inhibition of TG2 either by TG2 inhibitors or transfection of cells with TG2 shRNA block S100A4-accelerated cell migration in the KP1cells and in R37 cells treated with exogenous S100A4. Cell migration was also blocked by the treatment with the non-cell permeabilizing TG2 inhibitor R294, in the human breast cancer cell line MDA-MB-231 (Clone 16, which has a high level of TG2 expression). Inhibition was paralleled by a decrease in S100A4 polymer formation. co-immunoprecipitation and Far Western blotting assays and cross-linking assays showed not only the direct interaction between TG2 and S100A4, but also confirmed S100A4 as a substrate for TG2. Using specific functional blocking antibodies, a targeting peptide and a recombinant protein as a competitive treatment, we revealed the involvement of syndecan-4 and a5ß1 integrin co-signalling pathways linked by activation of PKCa in this TG2 and S100A4-mediated cell migration. We propose a mechanism for TG2-regulated S100A4-related mediated cell migration, which is dependent on TG2 crosslinking

The role of tissue transglutaminase (TG2) in regulating the tumour progression of the mouse colon carcinoma CT26

The multifunctional enzyme tissue transglutaminase (TG2) is reported to both mediate and inhibit tumour progression. To elucidate these different roles of TG2, we established a series of stable-transfected mouse colon carcinoma CT26 cells expressing a catalytically active (wild type) and a transamidating-inactive TG2 (Cys277Ser) mutant. Comparison of the TG2-transfected cells with the empty vector control indicated no differences in cell proliferation, apoptosis and susceptibility to doxorubicin, which correlated with no detectable changes in the activation of the transcription factor NF-?B. TG2-transfected cells showed increased expression of integrin ß3, and were more adherent and less migratory on fibronectin than control cells. Direct interaction of TG2 with ß3 integrins was demonstrated by immunoprecipitation, suggesting that TG2 acts as a coreceptor for fibronectin with ß3 integrins. All cells expressed the same level of TGFß receptors I and II, but only cells transfected with active TG2 had increased levels of TGFß1 and matrix-deposited fibronectin, which could be inhibited by TG2 site-directed inhibitors. Moreover, only cells transfected with active TG2 were capable of inhibiting tumour growth when compared to the empty vector controls. We conclude that in this colon carcinoma model increased levels of active TG2 are unfavourable to tumour growth due to their role in activation of TGFß1 and increased matrix deposition, which in turn favours increased cell adhesion and a lowered migratory and invasive behaviour

A multicenter phase III trial comparing irinotecan-gemcitabine (IG) with gemcitabine (G) monotherapy as first-line treatment in patients with locally advanced or metastatic pancreatic cancer

Our purpose was to determine the response rate and median and overall survival of gemcitabine as monotherapy versus gemcitabine plus irinotecan in advanced or metastatic pancreatic cancer. Patients with histologically or cytologically confirmed adenocarcinoma who were chemotherapy and radiotherapy naive were enrolled. Patients were centrally randomised at a one-to-one ratio to receive either gemcitabine monotherapy (900 mg m−2 on days 1, 8 and 15 every 4 weeks (arm G), or gemcitabine (days 1 and 8) plus irinotecan (300 mg m−2 on day 8) (arm IG), repeated every 3 weeks. The total number of cycles administered was 255 in the IG arm and 245 in the G arm; the median number of cycles was 3. In all, 145 patients (71 in arm IG and 74 in arm G) were enrolled; 60 and 70 patients from arms IG and G, respectively, were evaluable. A complete clinical response was achieved in three (4.3%) arm G patients; nine (15%) patients in arm IG and four (5.7%) in arm G achieved a partial response. The overall response rate was: arm IG 15% and arm G 10% (95% CI 5.96–24.04 and 95% CI 2.97–17.03, respectively; P=0.387). The median time to tumour progression was 2.8 months and 2.9 months and median survival time was 6.4 and 6.5 months for the IG and G arms, respectively. One-year survival was 24.3% for the IG arm and 21.8% for the G arm. No statistically significant difference was observed comparing gemcitabine monotherapy versus gemcitabine plus irinotecan in the treatment of advanced pancreatic cancer, with respect to overall and 1-year survival

A randomized phase III study of the docetaxel/carboplatin combination versus docetaxel single-agent as second line treatment for patients with advanced/metastatic Non-Small Cell Lung Cancer

<p>Abstract</p> <p>Background</p> <p>To compare the activity and toxicity of docetaxel/carboplatin (DC) doublet vs single agent docetaxel (D) as second-line treatment in patients with advanced non-small cell lung cancer (NSCLC).</p> <p>Methods</p> <p>Patients pre-treated with front-line platinum-free regimens, were randomized to receive either docetaxel/carboplatin (DC), (docetaxel 50 mg/m²; carboplatin AUC4; both drugs administered on days 1 and 15) or docetaxel single-agent (D), (docetaxel 50 mg/m²on days 1 and 15).</p> <p>Results</p> <p>Response rate was similar between the two arms (DC vs D: 10.4% vs 7.7%; p = 0.764). After a median follow-up time of 28.0 months for DC arm and 34.5 months for D arm, progression free survival (PFS) was significantly higher in the DC arm (DC vs D:3.33 months vs 2.60 months; p-value = 0.012), while no significant difference was observed in terms of overall survival (OS) (DC vs D: 10.3 months vs 7.70 months; p-value = 0.550). Chemotherapy was well-tolerated and grade III/IV toxicities were relatively infrequent. No toxic deaths were observed.</p> <p>Conclusions</p> <p>This study has not achieved its primary objective of significant OS prolongation with docetaxel/carboplatin combination over single-agent docetaxel in patients who had not received front-line docetaxel; however, the docetaxel/carboplatin combination was associated with a significant clinical benefit in terms of PFS.</p