catena-poly[mercury(II)-di-mu-bromo-mu-pyridazine-kappa N-2 : N ']

The crystal structure of [HgBr2(Pyo)](n) (Pyo = pyridazine, C4H4N2) consists of strands of octahedrally coordinated mercuric centers asymmetrically bridged by bromide and connected by the two neighboring N atoms of pyridazine molecules to complete the octahedral coordination of mercury. The Hg atoms lie on inversion centers.

Bis(tetraethylammonium) di-mu-bromo-bis[dibromomercurate(II)], (Et4N)(2)[Hg2Br6]

The structure of (Et4N)(2)[Hg2Br6] contains dinuclear [Hg2Br6](2-) species as isolated anions. Charge balance is achieved by ordered [Et4N](+) cations. An inversion centre is located at the centre of the [Hg2Br6](2-) unit.

Preparation and characterisation of palladium, platinum and manganese di(organo)carbene complexes from quinolinone and quinolinium precursors

A series of palladium, platinum and manganese di(organo) carbene complexes have been prepared from 4-chloro-N-methylquinolinone by processes that involve alkylation before or after attachment to the metal unit; the nucleophilic heteroatoms necessary for eventual carbene formation and stabilisation are separated from the C-donor atom by three bonds.

La pomice per il confezionamento di calcestruzzi leggeri strutturali:Meccanica dei materiali e delle strutture

Abstract. The possibility of using pumice aggregates for concrete in structural applications is discussed. In particular, the mix design of lightweight concrete for the manufacturing masonry units having proper strength, is discussed. Moreover, the design of the unit shape according to the technical code requirements and making it possible to arrange reinforcing steel bars is described. Reinforced bearing masonry walls, made with the concrete units in question, were manufactured and tests on the panels and on the designed units were carried out. For comparison, tests on concrete units and structural elements were carried out after the substitution of pumice aggregates with ordinary lightweight aggregates, proving that pumice can be considered an alternative to them. Sommario. L’uso della pomice come inerte per il confezionamento di calcestruzzo è poco diffuso sebbene essa sia stata usata già in antiche costruzioni come il Pantheon in Roma. In questo studio si affronta la possibilità di realizzare blocchi in calcestruzzo alleggerito con granuli di pomice. I blocchi, progettati e realizzati secondo le indicazioni normative correnti, sono stati usati per realizzare pannelli murari armati da sottoporre a carichi ciclici orizzontali. I risultati ottenuti, messi a confronto con quelli di pannelli realizzati con blocchi in cls alleggerito con argilla espansa, hanno mostrato la possibilità di utilizzare la pomice come validissima alternativa all’argilla espansa.

Gli strumenti della performance. Un’analisi dei Piani e delle Relazioni sulla Performance 2011 nei comuni di grandi dimensioni

No abstract available

Oltre il "Momento dell'Abolizione":Saggio in memoria di Louk Hulsman

This article is written to celebrate the fine contribution and constant optimism of Louk Hulsman to the debate about penal abolition, the rethinking of popular and political discourses on ‘crime’, and the institutionalised responses of the ‘criminal justice system’. Reflecting on his experiences of incarceration and on his critical analysis of the political economic relations of power, Louk Hulsman talked of the defining ‘moment of abolition’ – his reading of Thomas Mathiesen’s ground-breaking text, The Politics of Abolition. Having considered the key elements of Louk Hulsman’s work and its critical challenge to the criminological enterprise, the article explores the apparent political contradiction in campaigning for humane conditions while seeking abolition within the context of an ever-expanding, global prison-industrial complex.

Algorithms for Hidden Markov Models With Imprecisely Specified Parameters

Hidden Markov models (HMMs) are widely used models for sequential data. As with other probabilistic graphical models, they require the specification of precise probability values, which can be too restrictive for some domains, especially when data are scarce or costly to acquire. We present a generalized version of HMMs, whose quantification can be done by sets of, instead of single, probability distributions. Our models have the ability to suspend judgment when there is not enough statistical evidence, and can serve as a sensitivity analysis tool for standard non-stationary HMMs. Efficient inference algorithms are developed to address standard HMM usage such as the computation of likelihoods and most probable explanations. Experiments with real data show that the use of imprecise probabilities leads to more reliable inferences without compromising efficiency.

Discrete cyclic di-GMP-dependent control of bacterial predation versus axenic growth in Bdellovibrio bacteriovorus

Bdellovibrio bacteriovorus is a Delta-proteobacterium that oscillates between free-living growth and predation on Gram-negative bacteria including important pathogens of man, animals and plants. After entering the prey periplasm, killing the prey and replicating inside the prey bdelloplast, several motile B. bacteriovorus progeny cells emerge. The B. bacteriovorus HD100 genome encodes numerous proteins predicted to be involved in signalling via the secondary messenger cyclic di-GMP (c-di-GMP), which is known to affect bacterial lifestyle choices. We investigated the role of c-di-GMP signalling in B. bacteriovorus, focussing on the five GGDEF domain proteins that are predicted to function as diguanylyl cyclases initiating c-di-GMP signalling cascades. Inactivation of individual GGDEF domain genes resulted in remarkably distinct phenotypes. Deletion of dgcB (Bd0742) resulted in a predation impaired, obligately axenic mutant, while deletion of dgcC (Bd1434) resulted in the opposite, obligately predatory mutant. Deletion of dgcA (Bd0367) abolished gliding motility, producing bacteria capable of predatory invasion but unable to leave the exhausted prey. Complementation was achieved with wild type dgc genes, but not with GGAAF versions. Deletion of cdgA (Bd3125) substantially slowed predation; this was restored by wild type complementation. Deletion of dgcD (Bd3766) had no observable phenotype. In vitro assays showed that DgcA, DgcB, and DgcC were diguanylyl cyclases. CdgA lacks enzymatic activity but functions as a c-di-GMP receptor apparently in the DgcB pathway. Activity of DgcD was not detected. Deletion of DgcA strongly decreased the extractable c-di-GMP content of axenic Bdellovibrio cells. We show that c-di-GMP signalling pathways are essential for both the free-living and predatory lifestyles of B. bacteriovorus and that obligately predatory dgcC- can be made lacking a propensity to survive without predation of bacterial pathogens and thus possibly useful in anti-pathogen applications. In contrast to many studies in other bacteria, Bdellovibrio shows specificity and lack of overlap in c-di-GMP signalling pathways.