Queso fresco Alentejano de cabra con aceite esencial de orégano

El consumo de queso ha aumentado en los últimos años debido a la gran cantidad de tipos de quesos que podemos encontrar en el mercado, gracias a las diferentes clases de leche y de tecnologías existentes (Gouvea et al., 2017). El queso fresco es muy apreciado por su valor nutricional y su sabor agradable, considerándose un alimento saludable por su bajo contenido en sal (Gouvea et al. 2017; Lourenço et al., 2017). Este tipo de queso con bajo contenido en sal, pH próximo a la neutralidad y alta actividad de agua, favorece el crecimiento de microorganismos, acortando la vida útil del producto (Gadotti et al., 2014). Una buena alternativa para evitar la proliferación de microorganismos en los alimentos es el uso de aceites esenciales extraídos de plantas aromáticas y medicinales (Laranjo et al. 2017). En el aceite esencial de orégano uno de sus compuestos principales es el carvacrol, que es un compuesto fenólico con capacidad antimicrobiana (Burt, 2004; Laranjo et al., 2017). Existe un gran número de estudios in vitro que han determinado la concentración mínima inhibitoria del aceite esencial de orégano en torno a 0,28 mg.ml-1 – 1,25 mg.ml-1 (Burt, 2004; Laranjo et al., 2017). El objetivo de este estudio fue la comparación de queso fresco de cabra, natural, y queso fresco de cabra, con aceite esencial de orégano

Use of essential oils in food preservation

New alternatives for food conservation and preservation are now emerging, as many studies have shown that the use of synthetic preservatives and chemical additives is leading to intoxication, cancer and other degenerative diseases. This has led to a growing consumer concern and the desire to consume healthier products containing natural preservatives and additives instead of synthetic ones. This generates the need to look for conservation alternatives that cover the same antimicrobial properties and compatibility with food. In this search, new antimicrobial agents of natural origin, as is the case of essential oils (EOs) obtained from aromatic and medicinal plants, have been found. EOs have antimicrobial activity against a wide range of microorganisms and antioxidant activity, this is generally attributed to phenolic compounds owned by EOs. Many studies in vitro have defined EOs as effective antimicrobial and antioxidant compounds, but they are not much used in industry. Mediterranean dietary food products (meat and meat products, cheeses and fruits) are highly appreciated by consumers; their preservation with EOs would represent an added value. The present study reviews the existing research work on the use of EOs as food preservatives as an alternative to synthetic preservatives and chemical additives in Mediterranean food products

Electron transfer at the mineral/water interface: Selenium reduction by ferrous iron sorbed on clay

International audienceThe mobility and availability of the toxic metalloid selenium in the environment is largely controlled by sorption and redox reactions, which may proceed at temporal scales similar to that of subsurface water movement under saturated or unsaturated conditions. Since such waters are often anaerobic and rich in Fe2+, we investigated the long-term (≤ 1 month) kinetics of selenite (Se(IV)O3 -) sorption to montmorillonite in the presence of Fe2+ under anoxic conditions. A synthetic montmorillonite was used to eliminate the influence of structural Fe. In the absence of aqueous Fe2+, selenite was sorbed as outer-sphere sorption complex, covering only part of the positive edge sites, as verified by a structure-based MUSIC model and Se K-edge XAS (X-ray absorption spectroscopy). When selenite was added to montmorillonite previously equilibrated with Fe2+ solution however, slow reduction of Se and formation of a solid phase was observed with Se K-edge XANES (x-ray absorption near-edge spectroscopy) and EXAFS (extended x-ray absorption finestructure) spectroscopy. Iterative transformation factor analysis of XANES and EXAFS spectra suggested that only one Se reaction product formed, which was identified as nano-particulate Se(0). Even after one month, only 75% of the initially sorbed Se(IV) was reduced to this solid species. Mössbauer spectrometry revealed that before and after addition and reduction of Se, 5% of total sorbed Fe occurred as Fe(III) species on edge sites of montmorillonite (≈ 2 mmol kg-1). The only change observed after addition of Se was the formation of a new Fe(II) species (15%) attributed to the formation of an outer-sphere Fe(II)-Se sorption complex. The combined Mössbauer and XAS results hence clearly suggest that the Se and Fe redox reactions are not directly coupled. Based on the results of a companion paper, we hypothesize that the electrons produced in the absence of Se by oxidation of sorbed Fe(II) are stored, for example by formation of surface H2 species, and are then 3 available for the later Se(IV) reduction. The slow reaction rate indicates a diffusion controlled process. Homogeneous precipitation of an iron selenite was thermodynamically predicted and experimentally observed only in the absence of clay. Interestingly, half of Fe was oxidized in this precipitate (Mössbauer). Since DFT calculations predicted the oxidation of Fe at the water-FeSe solid interface only and not in the bulk phase, the average particle size of this precipitate does not exceed 2 nm. A comparison with the Mössbauer and XAS spectra of the clay samples demonstrates that such homogenous precipitation can be excluded as a mechanism for the observed slow Se reduction, emphasizing the role of abiotic, heterogeneous precipitation and reduction for the removal of Se from subsurface waters

Axillary lymph node imaging in mRNA, vector-based, and mix-and-match COVID-19 vaccine recipients: ultrasound features

Objectives To assess ultrasound characteristics of ipsilateral axillary lymph nodes after two doses of four different COVID-19 vaccination protocols, to determine whether these parameters differed with age, and to describe how they changed on follow-up imaging. Methods A total of 247 volunteer employees from our center who had received two doses of COVID-19 vaccination were recruited and followed prospectively. Axillary ultrasound of the ipsilateral vaccinated arm was performed the week after receiving the second dose to analyze lymph node features (number, long-axis, cortical thickness, morphology, and vascular imaging). Axillary lymphadenopathy resulting from four vaccination protocols—mRNA (BNT162b2, mRNA-1273), ChAdOx1-S, and mix-and-match—was compared. Analysis was conducted using the Kruskal-Wallis test and post hoc analysis with Bonferroni corrections. Nodal reactogenicity was evaluated for two age groups: young (< 45 years old) and middle-aged ( ≥ 45 years old). All parameters were compared between both groups using an unpaired-sample Student t test. A p value < 0.05 was considered statistically significant. Results Significantly higher values for total number of visible nodes, cortical thickness, Bedi’s classification (p < 0.001), and vascularity (p < 0.05) were observed in mRNA vaccine recipients compared to full ChAdOx1-S protocol recipients. Moreover, mix-and-match protocol recipients showed greater nodal cortical thickness and higher Bedi’s classification than full ChAdOx1-S recipients (p < 0.001). Analyses between age groups revealed greater cortical thickness, Bedi’s classification, and color Doppler signal in younger patients (p < 0.05). Conclusions Nodal parameters of Bedi’s classification and cortical thickness were more often increased in mRNA and mix-andmatch vaccine recipients when compared to ChAdOx1-S vaccine alone, especially in younger patients. Key Points • Hyperplastic lymphadenopathy was observed more frequently in mRNA and mix-and-match vaccine protocols compared to full vector-based vaccination. • Higher values for cortical thickness, Bedi’s classification, and color Doppler signal parameters were identified in younger patients. • Observed lymph node findings normalized in greater than 80% of patients by the third month following vaccination

Unraveling the Orbital Physics in a Canonical Orbital System KCuF3

We explore the existence of the collective orbital excitations, orbitons, in the canonical orbital system KCuF3 using the Cu L3-edge resonant inelastic x-ray scattering. We show that the nondispersive high-energy peaks result from the Cu2+  dd orbital excitations. These high-energy modes display good agreement with the ab initio quantum chemistry calculation, indicating that the dd excitations are highly localized. At the same time, the low-energy excitations present clear dispersion. They match extremely well with the two-spinon continuum following the comparison with Müller ansatz calculations. The localized dd excitations and the observation of the strongly dispersive magnetic excitations suggest that the orbiton dispersion is below the resolution detection limit. Our results can reconcile with the strong local Jahn-Teller effect in KCuF3, which predominantly drives orbital ordering

III Ciclo de Conferências do Conselho Técnico-Científico : temas atuais em investigação

A obra é constituída pelos resumos das comunicações apresentadas pelos docentes da Escola Superior Agrária do Instituto Politécnico de Castelo Branco e são referentes aos projetos de investigação nos quais estão envolvidos.O Conselho Técnico-Científico da Escola Superior Agrária (ESA), eleito para o biénio 2014-2016, tomou posse no dia 27 de março de 2014. Uma das iniciativas previstas no seu Plano de Atividades consistia no desenvolvimento de ações de divulgação de atividades técnico-científicas, com intervenção da ESA. Neste âmbito promoveu-se o III Ciclo de Conferências do Conselho Técnico-Científico, através do qual se procurou fomentar a difusão do conhecimento e valorizar os resultados de trabalhos de investigação e de experimentação, através da divulgação do seu contributo para o desenvolvimento tecnológico e da inovação de empresas e produtos. Com a presente publicação pretende dar-se a conhecer a um auditório mais vasto a informação apresentada e debatida publicamente, assim como promover uma maior colaboração entre entidades e instituições em ações suscetíveis de contribuir para o aumento da competitividade e do espírito empreendedor de empresas associadas ao setor agrícola e agroindustrial

Mercados del agua y uso de aguas regeneradas : aspectos ambientales

Los mercados de agua son unos instrumentos habilitados desde la Administración para minorar las presiones ejercidas sobre el escaso recurso. Cuentan con una importante regulación jurídica, que ha sido objeto de análisis y estudio por diversos expertos, también se ha evaluado su impacto económico, pero no han sido analizados de forma particular con el mismo interés los aspectos medioambientales que su implementación podría ocasionar tanto sobre las cuencas cedentes como receptoras. Por otra parte, la carestía del recurso hídrico en muchas zonas de España condiciona el uso de aguas regeneradas previamente tratadas, como fuente complementaria al regadío. En este trabajo se plantean los impactos ambientales que la puesta en marcha de un mercado de agua origina con especial énfasis en la transferencia de aguas que proceden de tratamiento y por la realización de infraestructuras.info:eu-repo/semantics/publishedVersio

Search for CP Violation in Charged D Meson Decays

We report results of a search for CP violation in the singly Cabibbo-suppressed decays D+ -> K- K+ pi+, phi pi+, K*(892)0 K+, and pi- pi+ pi+ based on data from the charm hadroproduction experiment E791 at Fermilab. We search for a difference in the D+ and D- decay rates for each of the final states. No evidence for a difference is seen. The decay rate asymmetry parameters A(CP), defined as the difference in the D+ and D- decay rates divided by the sum of the decay rates, are measured to be: A(CP)(K K pi) = -0.014 +/- 0.029, A(CP)(phi pi) = -0.028 +/- 0.036, A(CP)(K*(892) K) = -0.010 +/- 0.050, and A(CP)(pi pi pi) = -0.017 +/- 0.042.Comment: 13 pages, 5 figures, 1 table; Elsevier LaTe

Asymmetries between the production of D+ and D- mesons from 500 GeV/c pi- nucleon interactions as a function of xF and pt**2

We present asymmetries between the production of D+ and D- mesons in Fermilab experiment E791 as a function of xF and pt**2. The data used here consist of 74,000 fully-reconstructed charmed mesons produced by a 500 GeV/c pi- beam on C and Pt foils. The measurements are compared to results of models which predict differences between the production of heavy-quark mesons that have a light quark in common with the beam (leading particles) and those that do not (non-leading particles). While the default models do not agree with our data, we can reach agreement with one of them, PYTHIA, by making a limited number of changes to parameters used