793 research outputs found
Thermofield Quantum Electrodynamics in 1 + 1 Dimensions at Finite Chemical Potential: A Bosonization Approach
The recent generalization of the Lowenstein-Swieca operator solution of
Quantum Electrodynamics in 1+1 dimensions to finite temperature in Thermofield
Dynamics is further generalized to include a non-vanishing chemical potential.
The operator solution to the Euler-Lagrange equations respecting the
Kubo-Martin-Schwinger condition is constructed. Two forms of this condition and
their associated solutions are discussed. The correlation functions of an
arbitrary number of chiral densities are computed in the thermal theta-vacuum
Application of Gamma Irradiation Treatment on the Physicochemical and Microbiological Quality of an Artisanal Hard Cheese
The objective of this study was to evaluate the efficacy of gamma irradiation, applied to different cheese sample sizes (250g and 500 g), against Listeria monocytogenes, Escherichia coli, coliforms and aerobic colony counts. The effects on cheese physicochemical and odour properties and all costs involved for the treatment were quantified. The Cobalt-60 γ-irradiator was used at a maximum dose of 5.0 kGy. The values for cheese moisture (28.6%), ash (3.78%), pH (5.1), protein (29.6%), fat (30.7%), salt (1.95%) and water activity (0.92%) were within the acceptable ranges for hard cheese after gamma irradiation treatment. The colour (yellowness, redness, chroma and hue angle) and texture (cohesive-ness and springiness) values decreased (p < 0.05) with the treatment. Compounds such as safrole, acetylpyrazine, thiophene, 3,5-octadien-2-one and 1-Octen-3-one were present after the treatment, regardless of sample size. The gamma irradiation treatment resulted in 100%, 87.2%, 85.1% and 77.3% reduction in L. monocytogenes, coliforms, E. coli and aerobic colony counts, respectively. The study highlighted the efficacy of irradiation treatment and its affordability for resource-limited producers
La produzione di ceramica da mensa a Solunto: un esempio di continuit\ue0 tecnologica dall\u2bcet\ue0 arcaica a quella ellenistico-romana.
Solunto is one of the most important Phoenician-Punic colonies of north-western Sicily. Archaeometric researches carried
out in the last years ascertained a local production of transport amphorae during Archaic and Classic age (7th-5th century
B.C.) through mineralogical, petrographical and chemical analysis of ceramic samples, kiln refuses and local raw materials
(clays and alluvial sands). In connection with these earliest works, the present paper was focused on some specific forms
of fine-tempered table ware of Archaic age and/or Classic-Hellenistic age. This pottery has been recurrently brought to light
in Solunto and it is furthermore suspected to be, at least to some extent, a local reproduction. Thus a representative number
of samples corresponding in style and morphology to Greek-colonial productions were subjected to thin-section and chemical
analysis. Simultaneously, the same analytical routine was applied to an Hellenistic black-gloss ware form (Campana A), the
plate classified as Lamboglia 36, considering a number of samples coming from Solunto as well as from others close centers.
In both the cases the comparative elaboration of petrographic and chemical data concerning the ceramic samples and local
raw clays let us to distinguish between the products made in the Solunto\u2bcs kilns and the imports from Greece or the Greek
colony of Himera or from the Gulf of Naples area (for the black-gloss ware samples). Therefore, a durability of the
manufacture crosswise more than four centuries was demonstrated for the ceramic kilns which were working at Solunto,
which were able to reproduce several fine ware forms testifying an high technological level
DONKEY MILK SHELF LIFE: MICROBIOLOGY AND VOLATILE COMPOUNDS
Organoleptics properties are important to evaluate the shelf life of food products. Sensory analysis is generally used for this purpose. In this study psychrotrophic, mesophilic bacteria, and pH values were correlated to volatile compounds. The quality of raw donkey milk stored for 3, 7, 10, 14 and 28 days at two different temperatures (3°C and 7°C) was tested. Donkey milk volatiles for the first time in this study were identified. Different volatiles distribution were detected by Smart Nose and GCO during the trials and a correlation with bacteriological and pH data were shown. On the basis of the results the acceptability of 10 days storing at +3°C, and of 3-4 days at +7°C, for milk samples, was pointed out
Mesoglycan connects Syndecan-4 and VEGFR2 through Annexin A1 and formyl peptide receptors to promote angiogenesis in vitro.
Mesoglycan is a mixture of glycosaminoglycans (GAG) with fibrinolytic effects and the potential to enhance skin wound repair. Here, we have used endothelial cells isolated from Wild Type (WT) and Syndecan-4 null (Sdc4-/-) C57BL/6 mice to demonstrate that mesoglycan promotes cell motility and in vitro angiogenesis acting on the co-receptor Syndecan-4 (SDC4). This latter is known to participate in the formation and release of extracellular vesicles (EVs). We characterized EVs released by HUVECs and assessed their effect on angiogenesis. Particularly, we focused on Annexin A1 (ANXA1) containing EVs, since they may contribute to tube formation via interactions with Formyl peptide receptors (FPRs). In our model, the bond ANXA1-FPRs stimulates the release of vascular endothelial growth factor (VEGF-A) that interacts with vascular endothelial receptor-2 (VEGFR2) and activates the pathway enhancing cell motility in an autocrine manner, as shown by Wound-Healing/invasion assays, and the induction of Endothelial to Mesenchymal Transition (EndMT). Thus, we have shown for the first time that mesoglycan exerts its pro-angiogenic effects in the healing process triggering the activation of the three interconnected molecular axis: mesoglycan-SDC4, EVs-ANXA1-FPRs and VEGF-A-VEGFR2
On a mechanism for enhancing magnetic activity in tidally interacting binaries
We suggest a mechanism for enhancing magnetic activity in tidally interacting
binaries. We suppose that the deviation of the primary star from spherical
symmetry due to the tidal influence of the companion leads to stellar pulsation
in its fundamental mode. It is shown that stellar radial pulsation amplifies
torsional Alfv{\'e}n waves in a dipole-like magnetic field, buried in the
interior, according to the recently proposed swing wave-wave interaction
(Zaqarashvili 2001). Then amplified Alfv{\'e}n waves lead to the onset of
large-scale torsional oscillations, and magnetic flux tubes arising towards the
surface owing to magnetic buoyancy diffuse into the atmosphere producing
enhanced chromospheric and coronal emission.Comment: Accepted in Ap
Quantum Electrodynamics in Two-Dimensions at Finite Temperature. Thermofield Bosonization Approach
The Schwinger model at finite temperature is analyzed using the Thermofield
Dynamics formalism. The operator solution due to Lowenstein and Swieca is
generalized to the case of finite temperature within the thermofield
bosonization approach. The general properties of the statistical-mechanical
ensemble averages of observables in the Hilbert subspace of gauge invariant
thermal states are discussed. The bare charge and chirality of the Fermi
thermofields are screened, giving rise to an infinite number of mutually
orthogonal thermal ground states. One consequence of the bare charge and
chirality selection rule at finite temperature is that there are innumerably
many thermal vacuum states with the same total charge and chirality of the
doubled system. The fermion charge and chirality selection rules at finite
temperature turn out to imply the existence of a family of thermal theta vacua
states parametrized with the same number of parameters as in zero temperature
case. We compute the thermal theta-vacuum expectation value of the mass
operator and show that the analytic expression of the chiral condensate for any
temperature is easily obtained within this approach, as well as, the
corresponding high-temperature behavior
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