368 research outputs found
Morphometric approach to many-body correlations in hard spheres
We model the thermodynamics of local structures within the hard sphere liquid
at arbitrary volume fractions through the \textit{morphometric} calculation of
-body correlations. We calculate absolute free energies of local geometric
motifs in excellent quantitative agreement with molecular dynamics simulations
across the liquid and supercooled liquid regimes. We find a bimodality in the
density library of states where five-fold symmetric structures appear lower in
free energy than four-fold symmetric structures, and from a single reaction
path predict a relaxation barrier which scales linearly in the compressibility
factor. The method provides a new route to assess changes in the free energy
landscape at volume fractions dynamically inaccessible to conventional
techniques.Comment: 6+17 pages, 3 figure
Long-Lived Non-Equilibrium Interstitial-Solid-Solutions in Binary Mixtures
We perform particle resolved experimental studies on the heterogeneous
crystallisation process of two compo- nent mixtures of hard spheres. The
components have a size ratio of 0.39. We compared these with molecular dynamics
simulations of homogenous nucleation. We find for both experiments and
simulations that the final assemblies are interstitial solid solutions, where
the large particles form crystalline close-packed lattices, whereas the small
particles occupy random interstitial sites. This interstitial solution
resembles that found at equilibrium when the size ratios are 0.3 [Filion et
al., Phys. Rev. Lett. 107, 168302 (2011)] and 0.4 [Filion, PhD Thesis, Utrecht
University (2011)]. However, unlike these previous studies, for our system sim-
ulations showed that the small particles are trapped in the octahedral holes of
the ordered structure formed by the large particles, leading to long-lived
non-equilibrium structures in the time scales studied and not the equilibrium
interstitial solutions found earlier. Interestingly, the percentage of small
particles in the crystal formed by the large ones rapidly reaches a maximum of
around 14% for most of the packing fractions tested, unlike previous
predictions where the occupancy of the interstitial sites increases with the
system concentration. Finally, no further hopping of the small particles was
observed
Exposure to polychlorinated biphenyls and hexachlorobenzene, semen quality and testicular cancer risk
PURPOSE: We carried out a case-control study to investigate the possible role of occupational and environmental exposure to endocrine disruptors in the onset of testicular cancer (TC).
METHODS: We evaluated 125 TC patients and 103 controls. Seminal fluid examination and organochlorine analysis were performed in all subjects. Cases and controls were also interviewed using a structured questionnaire to collect demographic information, residence, andrological medical history and dietary information.
RESULTS: We found that a higher level of reproductive tract birth defects was associated with a higher risk of TC. With regard to diet, cases reported a higher consumption of milk and dairy products than controls. Overall, there was a statistically significant increase in TC risk in cases with detectable values of total polychlorinated organic compounds against controls (14.4 vs. 1.0 %; p < 0.001). TC patients with detectable levels of organochlorines had lower mean semen parameters than those with undetectable levels, although this difference was not statistically significant.
CONCLUSION: The International Agency for Research on Cancer recently included dioxin-like polychlorinated biphenyls (PCBs) in Group 1 of known human carcinogens. Our study confirmed and identified various risk factors for testicular cancer: cryptorchidism, consumption of milk and dairy products, parents' occupation and serum concentration of hexachlorobenzene and PCBs and, for the first time, we showed the correlation between semen quality and the serum concentration of these pollutants
Real-world efficacy and safety of nivolumab in previously-treated metastatic renal cell carcinoma, and association between immune-related adverse events and survival: the Italian expanded access program
Background: The Italian Renal Cell Cancer Early Access Program was an expanded access program that allowed access to nivolumab, for patients (pts) with metastatic renal cell carcinoma (mRCC) prior to regulatory approval. Methods: Pts with previously treated advanced or mRCC were eligible to receive nivolumab 3 mg/kg every 2 weeks. Pts included in the analysis had received ≥1 dose of nivolumab and were monitored for drug-related adverse events (drAEs) using CTCAE v.4.0. Immune-related (ir) AEs were defined as AEs displaying a certain, likely or possible correlation with immunotherapy (cutaneous, endocrine, hepatic, gastro-intestinal and pulmonary). The association between overall survival (OS) and irAEs was assessed, and associations between variables were evaluated with a logistic regression model. Results: A total of 389 pts were enrolled between July 2015 and April 2016. Overall, the objective response rate was 23.1%. At a median follow-up of 12 months, the median progression-free survival was 4.5 months (95% CI 3.7-6.2) and the 12-month overall survival rate was 63%. Any grade and grade 3-4 drAEs were reported in 124 (32%) and 27 (7%) of pts, respectively, and there were no treatment-related deaths. Any grade irAEs occurred in 76 (20%) of patients, 8% cutaneous, 4% endocrine, 2% hepatic, 5% gastro-intestinal and 1% pulmonary. Of the 22 drAEs inducing treatment discontinuation, 10 (45%) were irAEs. Pts with drAEs had a significantly longer survival than those without drAEs (median OS 22.5 versus 16.4 months, p = 0.01). Pts with irAEs versus without irAEs had a more significant survival benefit (median OS not reached versus 16.8 months, p = 0.002), confirmed at the landmark analysis at 6 weeks. The occurrence of irAEs displayed a strong association with OS in univariable (HR 0.48, p = 0.003) and multivariable (HR 0.57, p = 0.02) analysis. Conclusions: The appearance of irAEs strongly correlates with survival benefit in a real-life population of mRCC pts treated with nivolumab
LiCoO2 particles used in Li-ion batteries induce primary mutagenicity in lung cells via their capacity to generate hydroxyl radicals
Naturally occurring asbestos in Southern Italy: Geological and mineralogical investigation of fibrous antigorite from Calabrian serpentinites in view of its hazard assessment
Many-body correlations from integral geometry
In a recent letter we presented a framework for predicting the concentrations
of many-particle local structures inside the bulk liquid as a route to
assessing changes in the liquid approaching dynamical arrest. Central to this
framework was the morphometric approach, a synthesis of integral geometry and
liquid state theory, which has traditionally been derived from fundamental
measure theory. We present the morphometric approach in a new context as a
generalisation of scaled particle theory, and derive several morphometric
theories for hard spheres of fundamental and practical interest. Our central
result is a new theory which is particularly suited to the treatment of
many-body correlation functions in the hard sphere liquid, which we demonstrate
by numerical tests against simulation.Comment: 12 pages, 6 figure
SYN-EXHUMATION PERVASIVE BRITTLE DEFORMATION IN THE VOLTRI (NW ITALY) SERPENTINITE: THE CHRYSOTILE-CEMENTED ACQUASANTA BRECCIA
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