20 research outputs found
Nireas, International Water Research Center (Nireas-IWRC) of the University of Cyprus
The Nireas International Water Research Center (Nireas-IWRC) was established
in 2011 with the vision of reaching out to the wider scientific community to
exchange knowledge and best practices, to advance the state-of-the-art in water-related
scientific research and technologies, and to strengthen public awareness on waterrelated
issues. The CenterÂs mission is twofold: to conduct research of high international
caliber, while at the same time serving the research needs of Cypriot society, economy,
and industry. Among the CenterÂs many research, social, and dissemination activities, of
particular note are its efforts in the thematic research areas of: (i) Water Quality,
Monitoring and Treatment; (ii) Water Supply and Urban Water Management; and (iii)
Socioeconomic Analysis of Water-Related Issues. Nireas-IWRC researchers have already
secured significant national, EU, and international funding, and their research results
have widely been disseminated in peer-reviewed journals, international conferences,
technical reports, and technical workshops.[Contrib Sci 10:221-228 (2014)
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Sodium nanofluid for efficient oil recovery in heavy oil and oil sand reservoirs
Nanomaterials exhibit unique chemical and physical properties in comparison with their bulk-phase counterparts, attracting significant attention from the oil and gas industry in the hope of solving challenging issues. Current heavy oil extraction methods are costly and have unsatisfactory efficiency, and facing environmental restrictions increasingly. Our recent introduction of sodium (Na) nanofluid provides a promising method for heavy oil extraction since it shows improved oil recovery without burning carbon-containing fuels. Here, we conducted core-flooding tests to further evaluate the effect of this Na nanofluid on recovering oil from different formations, which had not been previously demonstrated, as well as to deepen our understanding of the underlying mechanisms. The Na nanofluid exhibited excellent oil-extraction efficiency for both types of heavy oil tested. The recovery mechanisms were found to be complicated. We also found that post-injection soaking and using the proper solvent to disperse the sodium nanoparticles are important for further boosting oil recovery
The Impact of a Check Dam on Groundwater Recharge and Sedimentation in an Ephemeral Stream
Despite the widespread presence of groundwater recharge check dams, there are few studies that quantify their functionality. The objectives of this study are (i) to assess groundwater recharge in an ephemeral river with and without a check dam and (ii) to assess sediment build-up in the check-dam reservoir. Field campaigns were carried out to measure water flow, water depth, and check-dam topography to establish water volume, evaporation, outflow, and recharge relations, as well as sediment build-up. To quantify the groundwater recharge, a water-balance approach was applied at two locations: at the check dam reservoir area and at an 11 km long natural stretch of the river upstream. Prediction intervals were computed to assess the uncertainties of the results. During the four years of operation, the check dam (storage capacity of 25,000 m3) recharged the aquifer with an average of 3.1 million m3 of the 10.4 million m3 yearâ1 of streamflow (30%). The lower and upper uncertainty limits of the check dam recharge were 0.1 and 9.6 million m3 yearâ1, respectively. Recharge from the upstream stretch was 1.5 million m3 yearâ1. These results indicate that check dams are valuable structures for increasing groundwater resources in semi-arid regions
Repeated Aqueous Film-Forming Foams Applications: Impacts on Polyfluoroalkyl Substances Retention in Saturated Soil
Historical
practices at firefighter-training areas involved
repeated
aqueous film-forming foams (AFFFs) applications, resulting in source
zones characterized by high concentrations of perfluoroalkyl and polyfluoroalkyl
substances (PFAS). Repeated applications of AFFF composed of 14 anionic
and 23 zwitterionic perfluoroalkyl substances (PFAS) were conducted
on a single one-dimensional saturated soil column to quantify PFAS
retention. An electrofluorination-based (3M) Milspec AFFF, which was
above the mixtureâs critical micelle concentration (CMC), was
at application strength (3%, v/v). Retention and retardation of PFAS
mass increased with each successive AFFF addition, although the PFAS
concentration profiles for subsequent applications differed from the
initial. Greater degree of mass retention and retardation correlated
with longer PFAS carbonâfluorine chain length and charged-headgroup
type and as a function of AFFF application number.
Anionic PFAS were increasingly retained with each subsequent AFFF
application, while zwitterionic PFAS exhibited an alternating pattern
of sorption and desorption. Surfactantâsurfactant adsorption
and competition during repeat AFFF applications that are at concentrations
above the CMC resulted in adsorbed PFAS from the first application,
changing the nature of the soil surface with preferential sorption
of anionic PFAS and release of zwitterionic PFAS due to competitive
elution. Applying a polyparameter quantitative structureâproperty
relationship developed to describe sorption of AFFF-derived PFAS to
uncontaminated, saturated soil was attempted for our experimental
conditions. The model had been derived for data where AFFF is below
the apparent CMC and our experimental conditions that included the
presence of mixed micelles (aggregates consisting of different kinds
of surfactants that exhibit characteristics properties different from
micelles composed of a single surfactant) resulted in overall PFAS
mass retained by an average of 27.3% ± 2.7% (standard error)
above the predicted values. The correlation was significantly improved
by adding a âmicelle parameterâ to account for cases
where the applied AFFF was above the apparent CMC. Our results highlight
the importance of interactions between the AFFF components that can
only be investigated by employing complex PFAS mixtures at concentrations
present in actual AFFF at application strength, which are above their
apparent CMC. In firefighter-training areas (AFFF source zones), competitive
desorption of PFAS may result in downgradient PFAS retention when
desorbed PFAS become resorbed to uncontaminated soil
Hydrocarbon Recovery From Oil Sands by Cyclic Surfactant Solubilization in Single-Phase Microemulsions
Nireas, International Water Research Center (Nireas-IWRC) of the University of Cyprus
The Nireas International Water Research Center (Nireas-IWRC) was established in 2011 with the vision of reaching out to the wider scientific community to exchange knowledge and best practices, to advance the state-of-the-art in water-related scientific research and technologies, and to strengthen public awareness on water-related issues. The Center’s mission is twofold: to conduct research of high international caliber, while at the same time serving the research needs of Cypriot society, economy, and industry. Among the Center’s many research, social, and dissemination activities, of particular note are its efforts in the thematic research areas of: (i) Water Quality, Monitoring and Treatment; (ii) Water Supply and Urban Water Management; and (iii) Socioeconomic Analysis of Water-Related Issues. Nireas-IWRC researchers have already secured significant national, EU, and international funding, and their research results have widely been disseminated in peer-reviewed journals, international conferences, technical reports, and technical workshops.[Contrib Sci 10:221-227 (2014)
Long-term sediment bioassay of lead toxicity in two generations of the marine amphipod Elasmopus laevis, S.I. Smith, 1873
Long-term Sediment Bioassay of Lead Toxicity in Two Generations of the Marine Amphipod Elasmopus laevis, S.I. Smith, 1873
Sediments are evaluated for toxicity by measuring mortality in a single cohort of amphipods in either acute (10-d) or chronic (28-d) bioassays. This investigation differed from conventional bioassays in four ways: Sublethal effects (fecundity) were estimated; the testing period was 60+ d; two successive generations were examined; and Elasmopus laevis Smith, 1873, amphipods were employed. Four test sediments were created between 58 and 424 ”g/g of lead using the 30-”g/g whole-sediment as the control. Bioaccumulated lead at 60 d varied as a linear function of lead concentration in the sediments. Fecundity, as estimated by offspring-per-chamber and/or percent reproductive success, was reduced as sediment lead concentrations increased and reproduction was delayed compared with the control. The reduction in offspring production per test chamber varied significantly as an inverse function of lead sediment concentration, best described by a curvilinear exponential equation. It was concluded that E. laevis exposed to 118 ”g/g and higher could not maintain a population as large as that in the control. Although the current sediment quality guideline for lead stipulates that adverse biological effects likely will occur above 218 ”g/g, this study revealed a statistically significant negative reproductive response at 118 ”g/g lead, and suggests that the current regulatory guideline for lead, based on lethality, should be reconsidere