La riproduzione di uno spazio subalterno. Abitazione, classi marginali e resistenza in una città del Sud

Il presente studio esplora gli sviluppi storici della stratificazione urbana in una città del Meridione d'Italia. Attraverso 85 interviste in profondità e l'analisi delle più importanti fasi della ricostruzione che hanno seguito un disastroso terremoto nel 1908, gli autori indagano le forze che, nel corso di un secolo, hanno spinto migliaia di individui in baracche e case popolari fatiscenti erette in città. Gli autori sostengono che l'"economia del disastro" e la "shock economy" non costituiscono un tratto saliente della nostra epoca. Al contrario, gli elementi che caratterizano i contemporanei processi speculativi da disastro erano largamente attivi già all'inizio del XX secolo. Questo articolo, pertanto, mostra le conseguenze di lunga durata degli approcci speculativi alla gestione dei disastri e riflette intorno alle forme di resistenza delle popolazioni subalterne nei confronti di un'organizzazione di vita che è iniziata all'indomani di un remoto terremoto e che condiziona ancora le condizioni di vita e i modi di riproduzione.This study explores the historical development of urban stratification in an Italian Southern city, Messina. By means of 85 in-depth interviews and the analysis of the most important phases of the reconstruction following a disastrous earthquake taking place in 1908, the authors investigate the coercive forces that, over the course of a century, have pushed thousands of individuals to occupy shanties and deprived project areas within the city. The authors claim that the "economy of disaster" and the "shock economy", are not a specific feature of current epoch. On the contrary, the elements characterizing the contemporary disaster-related speculative processes were largely active at the beginning of the XX century. This article, then, shows the long-lasting social consequences of speculative approaches to the management of disasters, and reflects on the forms of resistance of subaltern populations to an organization of life that started in the aftermath of a remote earthquake, and still affects their life condition and methods of reproduction

Leptocorticium gloeocystidiatum sp. nov. (Basidiomycota), a new corticioid fungus from Sicily, Italy

A new corticioid species, Leptocorticium gloeocystidiatum is described from Sicily, Italy. It is characterized by a resupinate, buff-coloured basidiome and microscopically by the presence of filiform leptocystidia, gloeocystidia, dendrohyphidia, and small ellipsoid, smooth basidiospores, non-reacting in Melzer's reagent. The species is compared with closest relatives. A key to the accepted species of Leptocorticium is provided

Probing 3-D matter distribution at z~2 with QSO multiple lines of sight

We investigate the 3-D matter distribution at z~2 with high resolution (R ~ 40000) spectra of QSO pairs and groups obtained with the UVES spectrograph at ESO VLT. Our sample is unique for the number density of objects and the variety of separations, between 0.5 and 7 proper Mpc. We compute the real space cross-correlation function of the Lyman-alpha forest transmitted fluxes. There is a significant clustering signal up to ~2 proper Mpc, which is still present when absorption lines with high column density (log N > 13.8) are excluded.Comment: Poster paper presented at the IAU Colloquium #199 on "Probing Galaxies through Quasar Absorption Lines" held in Shanghai, China from March 14th to 18th, 200

Tomography of the intergalactic medium with Ly-alpha forests in close QSO pairs

We study the three-dimensional distribution of non virialised matter at z~2 using high resolution spectra of QSO pairs and simulated spectra drawn from cosmological hydrodynamical simulations. We have collected the largest sample of QSO pairs ever observed with UVES at the ESO-VLT, with angular separations between ~1 and 14 arcmin. The observed correlation functions of the transmitted flux in the HI Lyman alpha forest along and transverse to the lines of sight are in good agreement implying that the distortions in redshift space due to peculiar velocities are small. The clustering signal is significant up to velocity separations of ~200 km/s, or about 3 h^{-1} comoving Mpc. The regions at lower overdensity (rho/ < 6.5) are still clustered but on smaller scales (Delta v < 100 km/s). The observed and simulated correlation functions are compatible at the 3 sigma level. A better concordance is obtained when only the low overdensity regions are selected for the analysis or when the effective optical depth of the simulated spectra is increased artificially, suggesting a deficiency of strong lines in the simulated spectra. We found that also a lower value of the power-law index of the temperature-density relation for the Lyman alpha forest gas improves the agreement between observed and simulated results. If confirmed, this would be consistent with other observations favouring a late HeII reionization epoch (at z~3). We remark the detection of a significant clustering signal in the cross correlation coefficient at a transverse velocity separation Delta v_{\perp} ~500 km/s whose origin needs further investigation.Comment: Accepted for publication in MNRAS, revised version matching the accepted on

Structure and stability of graphene nanoribbons in oxygen, carbon dioxide, water, and ammonia

We determine, by means of density functional theory, the stability and the structure of graphene nanoribbon (GNR) edges in presence of molecules such as oxygen, water, ammonia, and carbon dioxide. As in the case of hydrogen-terminated nanoribbons, we find that the most stable armchair and zigzag configurations are characterized by a non-metallic/non-magnetic nature, and are compatible with Clar's sextet rules, well known in organic chemistry. In particular, we predict that, at thermodynamic equilibrium, neutral GNRs in oxygen-rich atmosphere should preferentially be along the armchair direction, while water-saturated GNRs should present zigzag edges. Our results promise to be particularly useful to GNRs synthesis, since the most recent and advanced experimental routes are most effective in water and/or ammonia-containing solutions.Comment: accepted for publication in PR

Structure, Stability, Edge States and Aromaticity of Graphene Ribbons

We determine the stability, the geometry, the electronic and magnetic structure of hydrogen-terminated graphene-nanoribbons edges as a function of the hydrogen content of the environment by means of density functional theory. Antiferromagnetic zigzag ribbons are stable only at extremely-low ultra-vacuum pressures. Under more standard conditions, the most stable structures are the mono- and di-hydrogenated armchair edges and a zigzag edge reconstruction with one di- and two mono-hydrogenated sites. At high hydrogen-concentration ``bulk'' graphene is not stable and spontaneously breaks to form ribbons, in analogy to the spontaneous breaking of graphene into small-width nanoribbons observed experimentally in solution. The stability and the existence of exotic edge electronic-states and/or magnetism is rationalized in terms of simple concepts from organic chemistry (Clar's rule)Comment: 4 pages, 3 figures, accepted for publication by Physical Review Letter

Hydrothermal Decomposition of Amino Acids and Origins of Prebiotic Meteoritic Organic Compounds

The organic compounds found in carbonaceous chondrite meteorites provide insight into primordial solar system chemistry. Evaluating the formation and decomposition mechanisms of meteoritic amino acids may aid our understanding of the origins of life and homochirality on Earth. The amino acid glycine is widespread in meteorites and other extraterrestrial environments; other amino acids, such as isovaline, are found with enantiomeric excesses in some meteorites. The relationship between meteoritic amino acids and other compounds with similar molecular structures, such as aliphatic monoamines and monocarboxylic acids is unclear; experimental results evaluating the decomposition of amino acids have produced inconclusive results about the preferred pathways, reaction intermediates, and if the conditions applied may be compatible with those occurring inside meteoritic parent bodies. In this work, we performed extensive tandem metadynamics, umbrella sampling, and committor analysis to simulate the neutral mild hydrothermal decomposition mechanisms of glycine and isovaline and put them into context for the origins of meteoritic organic compounds. Our ab initio simulations aimed to determine free energy profiles and decomposition pathways for glycine and isovaline. We found that under our modeled conditions, methylammonium, glycolic acid, and sec-butylamine are the most likely decomposition products. These results suggest that meteoritic aliphatic monocarboxylic acids are not produced from decomposition of meteoritic amino acids. Our results also indicate that the decomposition of L-isovaline prefers an enantioselective pathway resulting in the production of (S)-sec-butylamine

Formation of p-n junction in polymer electrolyte-top gated bilayer graphene transistor

We show simultaneous p and n type carrier injection in bilayer graphene channel by varying the longitudinal bias across the channel and the top gate voltage. The top gate is applied electrochemically using solid polymer electrolyte and the gate capacitance is measured to be 1.5 $\mu F/cm^2$, a value about 125 times higher than the conventional SiO$_2$ back gate capacitance. Unlike the single layer graphene, the drain-source current does not saturate on varying the drain-source bias voltage. The energy gap opened between the valence and conduction bands using top and back gate geometry is estimated.Comment: 16 pages, 6 figure

Gonadotrophin-releasing hormone analogue or dienogest plus estradiol valerate to prevent pain recurrence after laparoscopic surgery for endometriosis: a multi-center randomized trial.

Abstract Objectives To evaluate the efficacy of dienogest + estradiol valerate (E2V) and gonadotrophin-releasing hormone analogue (GnRH-a) in reducing recurrence of pain in patients with chronic pelvic pain due to laparoscopically diagnosed and treated endometriosis. Design Multi-center, prospective, randomized study. Setting Three university departments of obstetrics and gynecology in Italy. Population Seventy-eight women who underwent laparoscopic surgery for endometriosis combined with chronic pelvic pain. Methods Post-operative administration of dienogest + E2V for 9 months (group 1) or GnRH-a monthly for 6 months (group 2). Main outcome measures A visual analogue scale was used to test intensity of pain before laparoscopic surgery at 3, 6 and 9 months of follow up. A questionnaire to investigate quality of life was administered before surgery and at 9 months of follow up. Results The visual analogue scale score did not show any significant differences between the two groups (p = 0.417). The questionnaire showed an increase of scores for all women compared with pre-surgery values, demonstrating a marked improvement in quality of life and health-related satisfaction with both treatments. No significant differences were found between the groups. The rate of apparent endometriosis recurrence was 10.8% in group 1 and 13.7% in group 2 (p = 0.962). Conclusion Both therapies seemed equally efficacious in preventing endometriosis-related chronic pelvic pain recurrence in the first 9 months of follow-up