Novel Ion Channels in Neurogenic Pain

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Growing CeO2_2 Nanoparticles within the Nano-Porous Architecture of the SiO2_2 Aerogel

In this study, new CeO$_2$-SiO$_2$ aerogel nanocomposites obtained by controlled growth of CeO$_2$ nanoparticles within the highly porous matrix of a SiO$_2$ aerogel are presented. The nanocomposites have been synthesized via a sol-gel route, employing cerium (III) nitrate as the CeO$_2$ precursor and selected capping agents to control the growth of the CeO$_2$ nanoparticles, which occurs during the supercritical drying of the aerogels. Samples with different loading of the CeO$_2$ dispersed phase, ranging from 5 to 15%, were obtained. The nanocomposites showed the morphological features typical of the SiO$_2$ aerogels such as open mesoporosity with surface area values up to 430 m$^2$·g$^{-1}$. TEM and XRD characterizations show that nanocrystals of the dispersed CeO$_2$ nanophase grow within the aerogel already during the supercritical drying process, with particle sizes in the range of 3 to 5 nm. TEM in particular shows that the CeO$_2$ nanoparticles are well distributed within the aerogel matrix. We also demonstrate the stability of the nanocomposites under high temperature conditions, performing thermal treatments in air at 450 and 900°C. Interestingly, the CeO$_2$ nanoparticles undergo a very limited crystal growth, with sizes up to only 7 nm in the case of the sample subjected to a 900°C treatment

Low mass dimuon production with the ALICE muon spectrometer

Low mass vector meson (ρ, ω,Φ ) production provides key information on the hot and dense state of strongly interacting matter produced in high-energy heavy ion collisions (called Quark Gluon Plasma). Strangeness enhancement is one of the possible signatures of the Quark Gluon Plasma formation and can be accessed through the measurement of Φ meson production with respect to ρ and Φ mesons, while the measurement of the Φ nuclear modification factor provides a powerful tool to probe the production dynamics and hadronization process in relativistic heavy ion collisions. Vector mesons can be detected through their decays into muon pairs with the ALICE muon spectrometer. This thesis presents the results on the measurement of the Φ differential cross section, as a function of the transverse momentum, in pp collisions at √s = 2.76 TeV; the measurement of the Φ fyield and of the nuclear modification factor RpA at forward and backward rapidity, as a function of the transverse momentum, in p-Pb collisions at √s = 5.02 TeV; the measurement of the Φ/ (ρ+ω) ratio, as well as of the Φ nuclear modification factors RAA and RCP , as a function of the number of participating nucleons, in Pb-Pb collisions at √sNN = 2.76 TeV

Insights into the Structure of Dot@Rod and Dot@Octapod CdSe@CdS Heterostructures

CdSe@CdS dot@rods with diameter around 6 nm and length of either 20, 27, or 30 nm and dot@octapods with pod diameters of ?15 nm and lengths of ?50 nm were investigated by X-ray absorption spectroscopy. These heterostructures are prepared by seed-mediated routes, where the structure, composition, and morphology of the CdSe nanocrystals used as a seed play key roles in directing the growth of the second semiconducting domain. The local structural environment of all the elements in the CdSe@CdS heterostructures was investigated at the Cd, S, and Se K-edges by taking advantage of the selectivity of X-ray absorption spectroscopy, and was compared to pure reference compounds. We found that the structural features of dot@rods are independent of the size of the rods. These structures can be described as made of a CdSe dot and a CdS rod, both in the wurtzite phase with a high crystallinity of both the core and the rod. This result supports the effectiveness of high temperature colloidal synthesis in promoting the formation of core@shell nanocrystals with very low defectivity. On the other hand, data on the CdSe@CdS with octapod morphology suggest the occurrence of a core composed of a CdSe cubic sphalerite phase with eight pods made of CdS wurtzite phase. Our findings are compared to current models proposed for the design of functional heterostructures with controlled nanoarchitecture

The UK Chinese population with kidney failure:Clinical characteristics, management and access to kidney transplantation using 20 years of UK Renal Registry and NHS Blood and Transplant data

BACKGROUND: Little is known about the clinical demographics of and access to transplantation for Chinese diaspora populations with kidney disease. METHODS: The UK Renal Registry provided data on adults with ethnicity recorded as ‘Chinese’ or ‘White’ starting Kidney Replacement Therapy (KRT) 1/1/97-31/12/17. Baseline characteristics were compared between Chinese and White patients. Multivariable logistic regression models were used to investigate the relationships between Chinese ethnicity and i) being listed for deceased-donor transplantation at start of KRT, ii) being listed 2 years after start of KRT, iii) pre-emptive kidney transplantation, iv) kidney transplantation 3 years after start of KRT, and v) living-donor kidney transplantation (LDKT). RESULTS: UK Chinese patients were younger at start of KRT (61.6 vs 65.6 years, p <0.001) and had more diabetic kidney disease (29% vs 20%, p<0.001) and glomerulonephritis (21% vs 13%, p<0.001) than White patients. We found evidence of interaction between ethnicity and sex. Compared to UK White men, UK Chinese men had lower odds of pre-emptive transplant (aOR 0.28, 95% CI [0.10–0.76]) and transplant within 3 years of KRT start (aOR 0.65, [95% CI 0.49–0.87], P = 0.004). UK White women and Chinese women had the same likelihood of pre-emptive transplant (aOR 0.78, 95% CI [0.38–1.61]), or transplant within 3 years of KRT start (aOR 0.94, 95% CI [0.60–1.46]). Both UK Chinese men and women had markedly lower odds of LDKT compared to Whites aOR 0.34 [95% CI 0.21–0.53]. CONCLUSIONS: UK Chinese are less likely to receive a LDKT. UK Chinese men have lower odds of accessing pre-emptive wait-listing and transplantation. Understanding whether these disparities reflect modifiable barriers will help ensure equitable access to transplantation