When do generalized entropies apply? How phase space volume determines entropy

We show how the dependence of phase space volume $\Omega(N)$ of a classical system on its size $N$ uniquely determines its extensive entropy. We give a concise criterion when this entropy is not of Boltzmann-Gibbs type but has to assume a {\em generalized} (non-additive) form. We show that generalized entropies can only exist when the dynamically (statistically) relevant fraction of degrees of freedom in the system vanishes in the thermodynamic limit. These are systems where the bulk of the degrees of freedom is frozen and is practically statistically inactive. Systems governed by generalized entropies are therefore systems whose phase space volume effectively collapses to a lower-dimensional 'surface'. We explicitly illustrate the situation for binomial processes and argue that generalized entropies could be relevant for self organized critical systems such as sand piles, for spin systems which form meta-structures such as vortices, domains, instantons, etc., and for problems associated with anomalous diffusion.Comment: 5 pages, 2 figure

On "Ergodicity and Central Limit Theorem in Systems with Long-Range Interactions" by Figueiredo et al

In the present paper we refute the criticism advanced in a recent preprint by Figueiredo et al [1] about the possible application of the $q$-generalized Central Limit Theorem (CLT) to a paradigmatic long-range-interacting many-body classical Hamiltonian system, the so-called Hamiltonian Mean Field (HMF) model. We exhibit that, contrary to what is claimed by these authors and in accordance with our previous results, $q$-Gaussian-like curves are possible and real attractors for a certain class of initial conditions, namely the one which produces nontrivial longstanding quasi-stationary states before the arrival, only for finite size, to the thermal equilibrium.Comment: 2 pages, 2 figures. Short version of the paper, accepted for publication in Europhysics Letters, (2009) in pres

Some Open Points in Nonextensive Statistical Mechanics

We present and discuss a list of some interesting points that are currently open in nonextensive statistical mechanics. Their analytical, numerical, experimental or observational advancement would naturally be very welcome.Comment: 30 pages including 6 figures. Invited paper to appear in the International Journal of Bifurcation and Chao

Evidence for Extended Aqueous Alteration in CR Carbonaceous Chondrites

We are currently studying the chemical interrelationships between the main rockforming components of carbonaceous chondrites (hereafter CC), e.g. silicate chondrules, refractory inclusions and metal grains, and the surrounding meteorite matrices. It is thought that the fine-grained materials that form CC matrices are representing samples of relatively unprocessed protoplanetary disk materials [1-3]. In fact, modern non-destructive analytical techniques have shown that CC matrices host a large diversity of stellar grains from many distinguishable stellar sources [4]. Aqueous alteration has played a role in homogeneizing the isotopic content that allows the identification of presolar grains [5]. On the other hand, detailed analytical techniques have found that the aqueously-altered CR, CM and CI chondrite groups contain matrices in which the organic matter has experienced significant processing concomitant to the formation of clays and other minerals. In this sense, clays have been found to be directly associated with complex organics [6, 7]. CR chondrites are particularly relevant in this context as this chondrite group contains abundant metal grains in the interstitial matrix, and inside glassy silicate chondrules. It is important because CR are known for exhibiting a large complexity of organic compounds [8-10], and only metallic Fe is considered essential in Fischer-Tropsch catalysis of organics [11-13]. Therefore, CR chondrites can be considered primitive materials capable to provide clues on the role played by aqueous alteration in the chemical evolution of their parent asteroids

Production of enzymatic extracts for aquafeeds by solid-state fermentation with Aspergillus ibericus of winery and olive mill wastes

[Excerpt] Introduction The replacement of fishmeal by plant ingredients in aquafeeds imposed new formulation strategies to overcome some nutritional restrictions associated with these alternative ingredients. Thus, supplementation of plant-based diets with feed additives, as exogenous enzymes and antioxidants compounds, has recently attracted increasing interest to improve feed utilization and to promote animal health. Solid state fermentation (SSF) of agro-industrial wastes has a high potential for the production of these additives, being a practical, economical, and environmentally-friendly process. Olive mill and winery wastes have valuable compounds that may be valorized thought SSF and that may be used as additives for aquafeeds. This study was conducted to optimize the production of non-starch carbohydrases through the SSF of the olive mill and winery wastes and to test its efficacy to improve the release of pentoses during digestion of a plant-based diet in European seabass.[...]Work supported by FCT PhD grant SFRH/BD/131219/2017, SFRH/BDP/114942/2016, IJFCT-POCI 01-0145-FEDER-030377 and MAR-02.01.01-FEAMP-0111info:eu-repo/semantics/publishedVersio

Novel fish feed supplements: giving value to agroindustrial wastes

Sustainable aquaculture requires the reduction of fish meal use in diets, by replacing it with ecofriendly ingredients, as that vegetal feedstuff not desirable for human consumption. However, these pose challenges due to the presence of antinutritional factors. The supplementation with some supplements, like exoenzymes and antioxidants, has shown potential to reduce their nutritional drawbacks. The solid-state fermentation (SSF) of agro-industrial wastes may be used to obtain such compounds. The goal of this work was to test the applicability of an SSF-extract, obtained through the SSF of an optimized mixture of three agro-industrial wastes with Aspergilus ibericus (30% EGM, 36% VTS, 34% EOP), determined previously with a simplex-centroid mixture design. The activity of this extract was measured to be xylanase: 1866.9 U/g (lyophilized extract); cellulose: 1563.6 U/g; β-glucosidase: 736.455 U/g, and total antioxidants: 439.4 μmol Trolox equivalents/g lyophilized extract; total phenols: 28.1 mg caffeic acid equivalents/g lyophilized extract. The efficiency of this extract as a feed additive in plant-based diets evaluated by an in vitro digestibility trial, analyzing its efficiency to improve the release of pentoses and antioxidants during digestion. The extract was used to supplement diets for Dicentrarchus labrax, with increasing levels of extract: 0, 4 and 8 U cellulase/g diet. Dietary supplementation with the extract led to the increase of pentose release, during alkaline digestion. The effect of the supplementation with the SSF extract on the release of antioxidants and phenols compounds are being evaluated and will be presented.Project SPO3 (ref. POCI-01-0145-FEDER-030377; FEDER-Operational Programme Competitiveness and Internationalization and FCT); project InovFeed (ref. MAR-02.01.01-FEAMP0111; Programa Operacional Mar2020); BioTecNorte (NORTE-01-0145-FEDER-000004; ERDF under the scope of Norte2020-Programa Operacional Regional do Norte)info:eu-repo/semantics/publishedVersio

Integrated RNA-seq and sRNA-seq analysis identifies novel nitrate-responsive genes in Arabidopsis thaliana roots

Background:Nitrate and other nitrogen metabolites can act as signals that regulate global gene expression in plants. Adaptive changes in plant morphology and physiology triggered by changes in nitrate availability are partly explained by these changes in gene expression. Despite several genome-wide efforts to identify nitrate-regulated genes, no comprehensive study of the Arabidopsis root transcriptome under contrasting nitrate conditions has been carried out. Results:In this work, we employed the Illumina high throughput sequencing technology to perform an integrated analysis of the poly-A + enriched and the small RNA fractions of the Arabidopsis thaliana root transcriptome in response to nitrate treatments. Our sequencing strategy identified new nitrate-regulated genes including 40 genes not represented in the ATH1 Affymetrix GeneChip, a novel nitrate-responsive antisense transcript and a new nitrate responsive miRNA/TARGET module consisting of a novel microRNA, miR5640 and its target, AtPPC3. Conclusions:Sequencing of small RNAs and mRNAs uncovered new genes, and enabled us to develop new hypotheses for nitrate regulation and coordination of carbon and nitrogen metabolism

Two highly divergent alcohol dehydrogenases of melon exhibit fruit ripening-specific expression and distinct biochemical characteristics

Alcohol dehydrogenases (ADH) participate in the biosynthetic pathway of aroma volatiles in fruit by interconverting aldehydes to alcohols and providing substrates for the formation of esters. Two highly divergent ADH genes (15% identity at the amino acid level) of Cantaloupe Charentais melon (Cucumis melo var. Cantalupensis) have been isolated. Cm-ADH1 belongs to the medium-chain zinc-binding type of ADHs and is highly similar to all ADH genes expressed in fruit isolated so far. Cm-ADH2 belongs to the short-chain type of ADHs. The two encoded proteins are enzymatically active upon expression in yeast. Cm-ADH1 has strong preference for NAPDH as a co-factor, whereas Cm-ADH2 preferentially uses NADH. Both Cm-ADH proteins are much more active as reductases with Kms 10–20 times lower for the conversion of aldehydes to alcohols than for the dehydrogenation of alcohols to aldehydes. They both show strong preference for aliphatic aldehydes but Cm-ADH1 is capable of reducing branched aldehydes such as 3-methylbutyraldehyde, whereas Cm-ADH2 cannot. Both Cm-ADH genes are expressed specifically in fruit and up-regulated during ripening. Gene expression as well as total ADH activity are strongly inhibited in antisense ACC oxidase melons and in melon fruit treated with the ethylene antagonist 1-methylcyclopropene (1-MCP), indicating a positive regulation by ethylene. These data suggest that each of the Cm-ADH protein plays a specific role in the regulation of aroma biosynthesis in melon fruit

Ergodicity and Central Limit Theorem in Systems with Long-Range Interactions

In this letter we discuss the validity of the ergodicity hypothesis in theories of violent relaxation in long-range interacting systems. We base our reasoning on the Hamiltonian Mean Field model and show that the life-time of quasi-stationary states resulting from the violent relaxation does not allow the system to reach a complete mixed state. We also discuss the applicability of a generalization of the central limit theorem. In this context, we show that no attractor exists in distribution space for the sum of velocities of a particle other than the Gaussian distribution. The long-range nature of the interaction leads in fact to a new instance of sluggish convergence to a Gaussian distribution.Comment: 13 pages,6 figure

Near-infrared photometry and spectroscopy of the low Galactic latitude globular cluster 2MASS-GC03

We present deep near-infrared photometry and spectroscopy of the globular cluster 2MASS-GC03 projected in the Galactic disk using MMIRS on the Clay telescope (Las Campanas Observatory) and VISTA Variables in the Via Lactea survey (VVV) data. Most probable cluster member candidates were identified from near-infrared photometry. Out of ten candidates that were followed-up spectroscopically, five have properties of cluster members, from which we calculate = -0.9 +/- 0.2 and a radial velocity of v_r > = -78 +- 12km/s. A distance of 10.8kpc is estimated from 3 likely RRLyrae members. Given that the cluster is currently at a distance of 4.2kpc from the Galactic center, the cluster's long survival time of an estimated 11.3 +/- 1.2 Gyr strengthens the case for its globular-cluster nature. The cluster has a hint of elongation in the direction of the Galactic center.Peer reviewedFinal Published versio