767 research outputs found
Pharmacokinetic basis of the neuromuscular blocking effects of vecuronium bromide; a study in animals and man
Thermal anomalies and fluid geochemistry framework in occurrence of the 2000-2001 Nizza Monferrate seismic sequence (northern Italy): Episodic changes in the fault zone heat flow or chemical mixing phenomena?
International audienceThe paper discusses the correlation between the heating of shallow groundwater over a 10 × 20 km wide area close to the town of Nizza Monferrato (Piemonte Region, Northern Italy) and the concomitant local seismic sequences during the period August 2000 ? July 2001. The first seismic sequence started on 21 August 2000 with a Ml = 5.2 earthquake. Within few hours, the local authorities received calls alerting that the groundwater temperature rose from 10 to 30°C in many shallow wells. Our geochemical experimental data and the geological-seismotectonic framework do not allow the hypothesis of simple fluid mixing between the thermal reservoir of Acqui Terme and the Nizza-Monferrato shallow groundwater to explain the observed thermal anomalies. On the other hand, we invoke more complex processes such as frictional heating, mechano-chemistry, fault-valve mechanism, adiabatic decompression and hydrogeologically driven heat flow i.e., thermal effects due to variations of basin-scale permeability field. All these processes are able to transmit heat to the surface and to generate a transient incremental heat flow better than the mass transfer occurring typically when fluids from different reservoirs mix
Accuracy of equations for predicting stature from knee height, and assessment of statural loss in an older Italian population.
Experimental study of CO2 sequestration by ECBM recovery: the case of Sulcis coal.
An ECBM (Enhanced Coal Bed Methane) feasibility study started for the Sulcis Coal Province (SW Sardinia, Italy) in December 2004: geochemical, structural-geology, stratigraphic and reservoir engineering considerations are discussed. The first newly gathered experimental data are discussed, including: fluid geochemistry (major and minor elements, dissolved gases, C and He isotopic ratios) of the reservoir, coal composition and experimental data on CO2/CH4 adsorption on coal. A MapInfo GIS structure was built up including stratigraphical, geo-structural, hydrogeochemical, coal-compositional and environmental impact information as well as the CO2 sources location and typology. Even if these data could be preliminary with respect to the coal characteritics effectively located at the future injection depth, they highlighted both the challenging positive and negative aspects of the Sulcis Coal Province versus the exploitation of the ECBM technique. The most important objective of this phase I of the project is the selection of the best Sulcis ECBM test-pilot site, which will be followed (Phase II) by the choice of a scaled up site and possibly by a future network (Phase III). These phases are foreseen to be accompanied by the selection of progressively added CO2 industrial sources, to be used within the project economic spreadsheet model, actually in evolution.
CO2 geological storage and CH4 production potentials in Sulcis have been grossly evaluated as a whole, in the frame of the Sardinia region CO2 sources, including the coal-fired power plants, both existent and foreseen (hundreds of millions of tonns of CO2 are possible to be stored underground in the next decades). The reservoir estimates, both for the CO2 injection and for the CH4 production are clearly involving to start the test-site phase exploitation, in the frame of an auspicabile international operative project
Nucleotide sequence of the structural gene (pyrB) that encodes the catalytic polypeptide of aspartate transcarbamoylase of Escherichia coli.
The deoxyribonucleotide sequence of pyrB, the cistron encoding the catalytic subunit of aspartate transcarbamoylase (carbamoylphosphate: L-aspartate carbamoyltransferase, EC 2.1.3.2), has been determined. The pyrB gene encodes a polypeptide of 311 amino acid residues initiated by an NH2-terminal methionine that is not present in the catalytically active polypeptide. The DNA sequence analysis revealed the presence of an eight-amino-acid sequence beginning at Met-219 that was not detected in previous analyses of amino acid sequence. This octapeptide sequence provides an additional component of the disordered loop in the equatorial domain of the catalytic polypeptide. It had been found previously that the catalytic polypeptide is expressed from a bicistronic operon that also produces the regulatory polypeptide encoded by pyrI. A single transcriptional control region precedes the structural gene of the catalytic polypeptide and a simple 15-base-pair region separates its COOH terminus from the structural gene of the regulatory polypeptide. The chain-terminating codon of the catalytic polypeptide may contribute to the ribosomal binding site for the regulatory polypeptide and thus assist coordinate expression of the two cistrons
Field dependent anisotropy change in a supramolecular Mn(II)-[3x3] grid
The magnetic anisotropy of a novel Mn(II)-[3x3] grid complex was investigated
by means of high-field torque magnetometry. Torque vs. field curves at low
temperatures demonstrate a ground state with S > 0 and exhibit a torque step
due to a field induced level-crossing at B* \approx 7.5 T, accompanied by an
abrupt change of magnetic anisotropy from easy-axis to hard-axis type. These
observations are discussed in terms of a spin Hamiltonian formalism.Comment: 4 pages, 4 figures, to be published in Phys. Rev. Let
Tuning the magnetic ground state of a novel tetranuclear Nickel(II) molecular complex by high magnetic fields
Electron spin resonance and magnetization data in magnetic fields up to 55 T
of a novel multicenter paramagnetic molecular complex [L_2Ni_4(N_3)(O_2C
Ada)_4](Cl O_4) are reported. In this compound, four Ni centers each having a
spin S = 1 are coupled in a single molecule via bridging ligands (including a
\mu_4-azide) which provide paths for magnetic exchange. Analysis of the
frequency and temperature dependence of the ESR signals yields the relevant
parameters of the spin Hamiltonian, in particular the single ion anisotropy gap
and the g factor, which enables the calculation of the complex energy spectrum
of the spin states in a magnetic field. The experimental results give
compelling evidence for tuning the ground state of the molecule by magnetic
field from a nonmagnetic state at small fields to a magnetic one in strong
fields owing to the spin level crossing at a field of ~25 T.Comment: revised version, accepted for publication in Physical Review
Eosinophilic ulcer of oral mucosa
La Úlcera Eosinófila de la Mucosa Oral, es una entidad poco frecuente, pobremente descrita en la literatura mundial. Se define como una lesión benigna autolimitada que si bien puede presentarse en distintas áreas de la cavidad bucal, presenta una marcada predilección por la mucosa ventral de la lengua. Clínicamente, se presenta como una lesión ulcerada de bordes indurados y sobreelevados. Los hallazgos histopatológicos son característicos y consisten en un infiltrado mixto rico en eosinófilos, acompañado de una población de grandes células mononucleadas. Recientes artículos basados en estudios inmunohistoquimicos, permiten afirmar la presencia de grandes linfocitos atípicos CD30+ y por lo tanto, incluir esta lesión en el espectro de las entidades simuladoras de desordenes linfoproliferativos.
A pesar de esto, el mecanismo etiopatogenico permanece oscuro y el trauma local juega un rol todavía no dilucidado; aunque se halla presente en la mayoría de las publicaciones, explicando el fenómeno como un mecanismo reactivo. La importancia de esta lesión, radica en su diagnostico diferencial por su semejanza clínica al carcinoma espinocelular, histoplasmosis, chancro sifilítico, Úlcera tuberculosa, carcinoma epidermoide y otras.
En nuestro trabajo se revisa la literatura y se discuten la características clínicas, histopatológicas y alternativas terapéuticas, a partir del artículo de un caso clínico en una paciente joven, que luego de la biopsia escisión como método para el diagnostico de certeza, se produce una recidiva de la lesión; lo que orientó el tratamiento hacia la cirugía combinada con corticoterapia local intralesional, logrando su remisión.Eosinophilic Ulcer of the Oral Mucosa, an entity, poorly deciphers in world-wide literature. It is defined as a self-limited, benign injury that although it can appear in different areas of the buccal cavity it presents a noticeable predilection via the ventral mucosa of the tongue. Clinically, one looks like an ulcer with hard and risen edges. The histo-pathological findings are typical and consist of a rich infiltrated mix of eosinophils, as well as a population of large mononuclear cells. Recent reports based on immunohistochemical studies allow us to confirm the presence of large atypical lymphocytes CD30+ and therefore include this lesion injury in the spectrum of lympho proliferative disorder simulators.
Despite this the etiopathogenic mechanism remains unknown and local trauma still plays an unexplained roll; although the majority of publications have explained the phenomena as a reactive mechanism. The importance of this injury is established by its differential diagnostic because of its clinical similarity to Spinocellular Carcinoma, Histoplasmosis, syphilitic chancre, Ulcer Tuberculosis, Epidermoid Carcinoma and others. In our work the literature is reviewed and clinical characteristics, histo-pathologies and alternative therapies are discussed. We use the case of a young patient who has a biopsy in an effort to diagnose with certainty has a relapse of the lesion which directs the treatment towards combined surgery and local intra lesion cortico therapy which led to successful remission.Facultad de OdontologíaFacultad de Ciencias Médica
Colorimetric response to anions by a "robust" copper(II) complex of a [9]aneN3 pendant arm derivative: CN- and I- selective sensing
The 1 : 1 complex [Cu(L)](BF4)2MeCN (1) of the tetradentate ligand 1-(2-quinolinylmethyl)-1,4,7-triazacyclononane (L) selectively changes its colour in the presence of CN in H2O and MeCN (without undergoing decomplexation from the macrocyclic ligand). The same complex in MeCN assumes different colours in the presence of CN or I
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