281 research outputs found
Incidence and impact on clinical outcome of infections with piperacillin/tazobactam resistant Escherichia coli in ICU: A retrospective study
Escherichia coli infections are frequent in ICU patients. The increased resistance to fluoroquinolones and amoxicillin/clavulanate of this pathogen mandates the prescription of broad-spectrum antibiotics such as piperacillin/tazobactam (PIP-TAZ) or third generation cephalosporins (3GC)
Node-like excitations in superconducting PbMo6S8 probed by scanning tunneling spectroscopy
We present the first scanning tunneling spectroscopy study on the Chevrel
phase PbMo6S8, an extreme type II superconductor with a coherence length only
slightly larger than in high-Tc cuprates. Tunneling spectra measured on
atomically flat terraces are spatially homogeneous and show well-defined
coherence peaks. The low-energy spectral weight, the zero bias conductance and
the temperature dependence of the gap are incompatible with a conventional
isotropic s-wave interpretation, revealing the presence of low-energy
excitations in the superconducting state. We show that our data are consistent
with the presence of nodes in the superconducting gap.Comment: To appear in PRB; 5 pages, 4 figure
Enhanced Electron Pairing in a Lattice of Berry Phase Molecules
We show that electron hopping in a lattice of molecules possessing a Berry
phase naturally leads to pairing. Our building block is a simple molecular site
model inspired by C, but realized in closer similarity with Na. In
the resulting model electron hopping must be accompanied by orbital operators,
whose function is to switch on and off the Berry phase as the electron number
changes. The effective hamiltonians (electron-rotor and electron-pseudospin)
obtained in this way are then shown to exhibit a strong pairing phenomenon, by
means of 1D linear chain case studies. This emerges naturally from numerical
studies of small -site rings, as well as from a BCS-like mean-field theory
formulation. The pairing may be explained as resulting from the exchange of
singlet pairs of orbital excitations, and is intimately connected with the
extra degeneracy implied by the Berry phase when the electron number is odd.
The relevance of this model to fullerides, to other molecular superconductors,
as well as to present and future experiments, is discussed.Comment: 30 pages, RevTe
Classification of primary and incisional abdominal wall hernias
A classification for primary and incisional abdominal wall hernias is needed to allow comparison of publications and future studies on these hernias. It is important to know whether the populations described in different studies are comparable.Comparative StudyConsensus Development ConferenceJournal ArticleReviewSCOPUS: ar.jinfo:eu-repo/semantics/publishe
Stratigraphic sequence and ages of volcanic units in the Gruithuisen region of the Moon
Drosophila Neurotrophins Reveal a Common Mechanism for Nervous System Formation
Neurotrophic interactions occur in Drosophila, but to date, no neurotrophic factor had been found. Neurotrophins are the main vertebrate secreted signalling molecules that link nervous system structure and function: they regulate
neuronal survival, targeting, synaptic plasticity, memory and cognition. We have identified a neurotrophic factor in
flies, Drosophila Neurotrophin (DNT1), structurally related to all known neurotrophins and highly conserved in insects.By investigating with genetics the consequences of removing DNT1 or adding it in excess, we show that DNT1
maintains neuronal survival, as more neurons die in DNT1 mutants and expression of DNT1 rescues naturally occurring
cell death, and it enables targeting by motor neurons. We show that Spa¨ tzle and a further fly neurotrophin superfamily member, DNT2, also have neurotrophic functions in flies. Our findings imply that most likely a neurotrophin was present in the common ancestor of all bilateral organisms, giving rise to invertebrate and vertebrate neurotrophins through gene or whole-genome duplications. This work provides a missing link between aspects of neuronal function in flies and vertebrates, and it opens the opportunity to use Drosophila to investigate further aspects of neurotrophin function and to model related diseases
Fibrin sealant in inguinal hernioplasty: an observational multicentre study in 1,201 patients
Meaning-making from wordless (or nearly wordless) picturebooks: what educational research expects and what readers have to say
Wordless (or nearly wordless) picturebooks are intriguing in terms of how readers make meaning from them. This article offers a conceptualization of existing studies in the field of education that use wordless picturebooks with young readers. While some of these studies contribute to understanding meaning-making, the pragmatic use of wordless picturebooks often does not take account of their particular nature and of the heightened role of the reader, leading to a mismatch between what the picturebook expects from the implied reader and the researchers’ expectations of what ‘real’ readers must do with these books. By highlighting observations from children’s literature scholarship and reader-response studies, this article aims to encourage a more interdisciplinary understanding of meaning-making. It also seeks to persuade educational researchers and mediators to consider investigative approaches that are not based on verbalization but are more in tune with the invitations that wordless picturebooks extend to young readers
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