2,055 research outputs found
Field Induced Staggered Magnetization and Magnetic Ordering in
We present a D NMR investigation of the gapped spin-1/2 compound . Our measurements reveal the presence of a magnetic
field induced transverse staggered magnetization (TSM) which persists well
below and above the field-induced 3D long-range magnetically ordered (FIMO)
phase. The symmetry of this TSM is different from that of the TSM induced by
the order parameter of the FIMO phase. Its origin, field dependence and
symmetry can be explained by an intra-dimer Dzyaloshinskii-Moriya interaction,
as shown by DMRG calculations on a spin-1/2 ladder. This leads us to predict
that the transition into the FIMO phase is not in the BEC universality class.Comment: 4 page
Guidelines for the monitoring of Lucanus cervus
Lucanus cervus is one of the most charismatic saproxylic beetles, widely distributed in Europe. The species is typical of mature deciduous forests, especially oak woodlands. Loss and fragmentation of suitable habitats is one of the major threats for this species which is included in Annex II of the Habitats Directive. Despite several studies carried out in the last years for the monitoring methods of the species, an analytical comparison between them is still lacking. The aims of this paper are (i) to review the current knowledge about systematics, ecology and conservation practices on L. cervus and (ii) to present the research carried out during the Life MIPP project, in order to define a standard monitoring method with a suitable protocol to be used for addressing the obligations of the Habitats Directive. Overall, five methods were tested during three years in two different study areas. Based on these results, a suitable standard method for L. cervus is proposed in this paper and, in order to assess the conservation status of populations and to compare them over time, a simple method for the calculation of a reference value is provided
Quantum-critical spin dynamics in quasi-one-dimensional antiferromagnets
By means of nuclear spin-lattice relaxation rate 1/T1, we follow the spin
dynamics as a function of the applied magnetic field in two gapped
one-dimensional quantum antiferromagnets: the anisotropic spin-chain system
NiCl2-4SC(NH2)2 and the spin-ladder system (C5H12N)2CuBr4. In both systems,
spin excitations are confirmed to evolve from magnons in the gapped state to
spinons in the gapples Tomonaga-Luttinger-liquid state. In between, 1/T1
exhibits a pronounced, continuous variation, which is shown to scale in
accordance with quantum criticality. We extract the critical exponent for 1/T1,
compare it to the theory, and show that this behavior is identical in both
studied systems, thus demonstrating the universality of quantum critical
behavior
Afatinib in the first-line treatment of patients with non-small cell lung cancer: clinical evidence and experience
Epidermal growth factor receptor (EGFR) gene mutations identify a molecularly defined subset of non-small cell lung cancer (NSCLC) patients who display an excellent sensitivity to EGFR tyrosine kinase inhibitors (TKIs). First-generation reversible EGFR TKIs, gefitinib and erlotinib have been proven to improve the objective response rate and to prolong the progression-free survival compared with standard chemotherapy in large phase III trials. Unfortunately, virtually all patients develop resistance to treatment, usually within 9–12 months. Afatinib is an irreversible ErbB family inhibitor initially designed to overcome the development of resistance. Compared with gefitinib in a first-line setting, afatinib prolonged progression-free survival and time to treatment failure, without impacting on overall survival in the general population of EGFR-mutant patients. However, afatinib has been shown to prolong overall survival in the subset of patients with an EGFR exon 19 deletion compared with chemotherapy. The aim of this review is to summarize the clinical evidence available to date and to critically discuss the place in therapy of afatinib in the rapidly expanding landscape of EGFR-mutant NSCLC first-line therapy
L'anatomia endodontica dei secondi molari superiori: ricerca ex vivo
Aim: of the present study was to deter- mine anatomic complexities which can be seen in maxillary second molars, with a specific attention to the presence of MB2 (second mesio-buccal) canals. Methodology: 50 maxillary second molars, which had been extracted for periodontal reasons, were selected for the study, following strict exclusion cri- teria. After determining the different roots, only the mesio-buccal one was examined. Location and number of canals were determined (i) after a normal access cavity, (ii) after a wider removal of dentine from the chamber floor, and (iii) after sectioning the root 4 mm be- low the cementum-enamel junction. Data were collected and analyzed. Results: MB2 canals were present in 44% of the examined teeth (20% of ca- ses showed Weine 2 configuration, while the remaining 24% showed Weine 3 configuration). It was possible to estabilish patency in MB2 canals only in 28% of cases.
Conclusions: MB2 canals are often present in maxillary second molars, being individuated in nearly half cases. This possibility and the presence of an indipendent apex make the research of MB2 canals mandatory during the endodontic treatment
Variabilidade genética e taxa de cruzamento em progênies da população de melhoramento de Stylosanthes guianensis.
bitstream/item/110778/1/BP32-em-alta.pd
Comparação de três métodos de extração de DNA genômico para análises moleculares em Stylosanthes guianensis.
O objetivo deste trabalho foi comparar a quantidade e qualidade do DNA isolado de folhas de S. guianensis pelos métodos de Bonato et al. (2002), de Faleiro et al. (2003) e um método baseado no de Bonato et al. (2002), mas com modificações que resultem um DNA mais puro e em quantidade suficiente para execução de diversas análises moleculares, incluindo amplificação, clonagem e sequenciamento.bitstream/CNPGC-2010/13216/1/CT36.pd
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