Interactive Learning-Based Realizability for Heyting Arithmetic with EM1

We apply to the semantics of Arithmetic the idea of ``finite approximation'' used to provide computational interpretations of Herbrand's Theorem, and we interpret classical proofs as constructive proofs (with constructive rules for $\vee, \exists$) over a suitable structure \StructureN for the language of natural numbers and maps of G\"odel's system \SystemT. We introduce a new Realizability semantics we call ``Interactive learning-based Realizability'', for Heyting Arithmetic plus \EM_1 (Excluded middle axiom restricted to $\Sigma^0_1$ formulas). Individuals of \StructureN evolve with time, and realizers may ``interact'' with them, by influencing their evolution. We build our semantics over Avigad's fixed point result, but the same semantics may be defined over different constructive interpretations of classical arithmetic (Berardi and de' Liguoro use continuations). Our notion of realizability extends intuitionistic realizability and differs from it only in the atomic case: we interpret atomic realizers as ``learning agents''

Interaction potentials for soft and hard ellipsoids

Using results from colloid science we derive interaction potentials for computer simulations of mixtures of soft or hard ellipsoids of arbitrary shape and size. Our results are in many respects reminicent of potentials of the Gay-Berne type but have a well-defined microscopic interpretation and no adjustable parameters. Since our potentials require the calculation of similar variables, the modification of existing simulation codes for Gay-Berne potentials is straightforward. The computational performance should remain unaffected.Comment: 8 pages, 4 figure

An Externally Fired Micro Combined-Cycle, with Largely Adjustable Steam Turbine, in a CHP System

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Hansenula polymorpha NMR2 and NMR4, two new loci involved in nitrogen metabolite repression

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Influence of perineural invasion in predicting overall survival and disease-free survival in patients With locally advanced gastric cancer

Background The aim of the present study was to evaluate the prognostic significance of perineural invasion (PNI) in locally advanced gastric cancer patients who underwent D2 gastrectomy and adjuvant chemotherapy. Methods The records of a series of 103 patients undergoing D2 gastrectomy with curative intent combined with adjuvant chemotherapy from January 2004 to December 2014 were retrospectively reviewed. Results PNI was positive in 47 (45.6%) specimens. The 1-, 3-, and 5-year overall survival rates were 81%, 55%, and 42%, respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 76%, 57%, and 49%, respectively. A multivariate analysis showed that age number of positive lymph nodes, T stage, and PNI were independently associated with overall survival. Regarding DFS, the multivariate analysis showed that only PNI was independently associated with DFS. Conclusions PNI and T stage and positive lymph nodes are independent markers of poor prognosis in patients with gastric cancer. PNI should be incorporated in the postoperative staging system for planning follow-up after surgery and in our opinion to propose more aggressive postoperative therapies in PNI-positive patients

Recovery from a cycling time trial is enhanced with carbohydrate-protein supplementation vs. isoenergetic carbohydrate supplementation

Background: In this study we assessed whether a liquid carbohydrate-protein (C+P) supplement (0.8 g/kg C; 0.4 g/kg P) ingested early during recovery from a cycling time trial could enhance a subsequent 60 min effort on the same day vs. an isoenergetic liquid carbohydrate (CHO) supplement (1.2 g/kg). Methods: Two hours after a standardized breakfast, 15 trained male cyclists completed a time trial in which they cycled as far as they could in 60 min (AMex) using a Computrainer indoor trainer. Following AMex, subjects ingested either C+P, or CHO at 10, 60 and 120 min, followed by a standardized meal at 4 h post exercise. At 6 h post AMex subjects repeated the time trial (PMex). Results: There was a significant reduction in performance for both groups in PMex versus AMex. However, performance and power decreases between PMex and AMex were significantly greater (p ≤ 0.05) with CHO (-1.05 ± 0.44 km and -16.50 ± 6.74 W) vs C+P (-0.30 ± 0.50 km and -3.86 ± 6.47 W). Fat oxidation estimated from RER values was significantly greater (p ≤ 0.05) in the C+P vs CHO during the PMex, despite a higher average workload in the C+P group. Conclusion: Under these experimental conditions, liquid C+P ingestion immediately after exercise increases fat oxidation, increases recovery, and improves subsequent same day, 60 min efforts relative to isoenergetic CHO ingestion

Core charge distribution and self assembly of columnar phases: the case of triphenylenes and azatriphenylenes

<p>Abstract</p> <p>Background</p> <p>The relation betweeen the structure of discotic molecules and columnar properties, a crucial point for the realization of new advanced materials, is still largely unknown. A paradigmatic case is that hexa-alkyl-thio substituted triphenylenes present mesogenic behavior while the corresponding azatriphenylenes, similar in shape and chemical structure, but with a different core charge distribution, do not form any liquid crystalline mesophase. This study is aimed at investigating, with the help of computer simulations techniques, the effects on phase behaviour of changes of the charge distribution in the discotic core.</p> <p>Results</p> <p>We described the shape and the pair, dispersive and electrostatic, interactions of hexa alkyl triphenylenes by uniaxial Gay-Berne discs with embedded point charges. Gay-Berne parameters were deduced by fitting the dispersive energies obtained from an atomistic molecular dynamics simulation of a small sample of hexa-octyl-thio triphenylene molecules in columnar phase, while a genetic algorithm was used to get a minimal set of point charges that properly reproduces the ab anitio electrostatic potential. We performed Monte Carlo simulations of three molecular models: the pure Gay-Berne disc, used as a reference, the Gay-Berne disc with hexa-thio triphenylene point charges, the Gay-Berne disc with hexa-thio azatriphenylene point charges. The phase diagram of the pure model evidences a rich polymorphism, with isotropic, columnar and crystalline phases at low pressure, and the appearance of nematic phase at higher pressure.</p> <p>Conclusion</p> <p>We found that the intermolecular electrostatic potential among the cores is fundamental in sta-bilizing/destabilizing columnar phases; in particular the triphenylene charge distribution stabilizes the columnar structure, while the azatriphenylene distribution suppresses its formation in favor of the nematic phase. We believe the present model could be successfully employed as the basis for coarse-grained level simulations of a wider class of triphenylene derivatives.</p

The importance of accountability for the relationship between governance and performance of UK charities

The aim of this paper is to analyse the relationships between governance characteristics of non-profit organizations (NPOs) (CEO duality and board size) and their performance, considered as their ability to collect financial resources. The study is conducted on a sample of 200 UK registered charities that work in a context characterized by a medium to high level of “mandatory” accountability. With a regression analysis we verify strong positive relationships between the NPOs’ financial performance and the CEO duality and board size. Further analyses show that if the charities increase their level of accountability through the use of additional voluntary disclosure mechanisms and tools such as the use of social networks, these relationships are confirmed. Qualitative characteristics of governance and voluntary accountability of UK charities are also analysed in association with some classes of revenues using the logistic regression method and the multiple correspondence analysis

Stability of Dirac cone in artificial graphene

Trabajo presentado al 18th ETSF Workshop celebrado en Luxemburgo del 1 al 4 de Octubre de 2013.ETSF - European Theoretical Spectroscopy Facility I3 (211956).Peer Reviewe