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Effect of temperature of thermotreatment on electrical conductivity of radiata pine timber

  • Fernández-Golfín, J. I.
  • Conde García, M.
  • Fernández-Golfín, J. J.
  • Conde García, M.
  • Hermoso, E.
  • Cabrero, J. C.
This paper analyzes the effect of heat treatment temperature on the electrical conductivity of radiata pine wood. On specimens of radiata pine of the Basque Country provenance (Spain), heat treated at 190°C and 210°C by the method Thermowood as well as not treated matched samples, conditioned up to constant mass at the standard conditions of 20°C/40%; 20°C/65% and 20°C/90% RH the electrical resistance (longitudinal and transverse) was measured and a Samuelsson model fitted to describe the relationship between the electrical resistance and moisture content of each material. From the data is concluded that the temperature employed in the thermal treatment timber not only affects equilibrium moisture content of wood but also to its electrical conductivity, being this effect maximum in the processing performed at 210°C.

Bioactive compounds content and total antioxidant activity of two savoy cabbages

  • Fernández-León, A. M.
  • Lozano, M.
  • González, D.
  • Ayuso, M. C.
  • Fernández-León, M. F.
The bioactive compounds, as well as the in vitro antioxidant activity of two Savoy cabbage cultivars, Dama and Leticia, grown in west of Spain under similar conditions were identified, quantified and compared. We found that cv. Dama presented in general betters results when compared with cv. Leticia. Cv. Dama presented higher concentrations of chlorophyll a (2.26 mg/100 g fresh weight), total phenolic content (102.71 mg of chlorogenic acid equivalent/100 g fresh weight) and total intact glucosinolates (195.22 μmol of sinigrin equivalent/100 g fresh weight). Thus, cv. Dama exhibited higher values of in vitro antioxidant activity.

Threat or opportunity? Browsing preferences and potential impact of Ammotragus lervia on woody plants of a Mediterranean protected area

  • Fernández-Olalla, M.
  • Martínez-Jauregui, M.
  • Perea, R.
  • Velamazán, M.
  • San Miguel, A.
Much of the biodiversity in the Mediterranean region depends upon extensive livestock rearing. However, this activity is decreasing, especially in arid environments, where considerable biodiversity loss is expected in the near future. Meanwhile, wild ungulate populations are regaining long lost territories and densities. The question arises as to how far wild ungulates could substitute the ecological role traditionally played by extensive livestock. This study focuses on the effect of an exotic wild ungulate, the aoudad (Ammotragus lervia), on the woody vegetation of a semiarid protected area in Southeast Spain where it was introduced in 1970. Forty-five field surveys provided information on the effect of browsing on 92 woody plant species and on the aoudad's feeding behavior. Small shrubs were the most preferred species and showed, on average, higher levels of browsing damage. However, browsing intensity was low in broadleaved trees and negligible in conifers. Highly preferred and sparse shrub species might be severely affected by medium to high aoudad densities. The aoudad could become an opportunity for arid environments that lack native wild ungulates and traditional livestock grazing, since it could partially fulfill most ecological roles played by livestock. However, it could also become a threat should it become overabundant. © 2016 Elsevier Ltd

Acceptability of lamb fed on pasture, concentrate or combinations of both systems by European consumers

  • Font i Furnols, M.
  • Realini, C. E.
  • Guerrero, L.
  • Oliver, M. A.
  • Sañudo, C.
  • Campo, M. M.
  • Nute, G. R.
  • Cañeque, V.
  • Álvarez, I.
  • San Julián, R.
  • Luzardo, S.
  • Brito, G.
  • Montossi, F.
It is well known that the eating quality of lamb is highly affected by feeding systems. The aim of this study was to ascertain acceptability of Uruguayan lamb meat from animals fed on different diets (only pasture-D1, only concentrate-D4 and two combinations of both systems-D3 and D4) by consumers from different European countries (Spain, Germany, United Kingdom and France). One hundred and twenty castrated Corriedale lambs were reared to 28.2 ± 0.8 kg live weight and then thirty lambs were allocated to each diet and reared to 40 kg live weight. Sections of loin were cooked using contact grills until the internal temperature of the muscle reached 72 °C (65 °C in France), cut and then served to consumers. A minimum of 180 consumers per country evaluated overall liking, flavour and tenderness acceptability of lamb from the 4 diets in sessions of 10 consumers using 8-point category scales. Globally consumers preferred lamb fed on concentrate or the combination of concentrate and pasture to lamb fed only on pasture. However, different segments of consumers were identified in each country based on their lamb acceptability. This information contributes to the identification of developing different commercial strategies in relation to the consumer segments found. © 2008 Elsevier Ltd. All rights reserved.

Short-term intake of β-carotene-supplemented diets enhances ovarian function and progesterone synthesis in goats

  • Arellano-Rodriguez, G.
  • Meza-Herrera, C. A.
  • Rodriguez-Martinez, R.
  • Dionisio-Tapia, R.
  • Hallford, D. M.
  • Mellado, M.
  • Gonzalez-Bulnes, A.
The effect of β-carotene supplementation upon luteal activity, measured as number (CLT) and volume (VLT) of corpus luteum, and P4 synthesis in goats, was evaluated. Goats (n = 22, 34 months) were randomly assigned to one of two experimental groups (i) β-carotene [Beta, n = 10; body weight (BW = 44.8 ± 1.45 kg), body condition score (BCS = 3.25 ± 0.07)], and (ii) Control (Control, n = 12; BW = 45.30 ± 1.32 kg, BCS = 3.33 ± 0.06). Upon oestrus synchronization, the Beta group received 50 mg of β-carotene per day during 35 days pre- and 17 days post-ovulation. The day 4, 8, 12 and 16 post-ovulation, blood samples were collected for quantification of serum P4 concentrations by radioimmmunoassay, and transrectal ultrasonographic scanning was performed at day 18 for evaluating CLT and VLT. Overall, CLT and VLT mean were 3.10 and 2211.1 mm3 respectively. The Beta-goats depicted both the largest values for CLT (p = 0.07) and serum P4 levels (p = 0.05), with no differences (p = 0.53) for VLT between treatments. Results suggest a higher efficiency within the cellular-enzymatic groups defining the steroidogenic pathways in the β-carotene-supplemented goats, generating a larger P4 synthesis. The last is essential for ovulation of healthy oocytes, maintenance of uterine quiescence, nourishment and survival of the embryo around implantation; all of them of paramount significance during the maternal recognition of pregnancy process. © 2008 Blackwell Verlag GmbH.

Seasonal changes in reproductive activity, sperm variables and sperm freezability in Blanca Andaluza bucks

  • Gallego-Calvo, L.
  • Gatica, M. C.
  • Santiago-Moreno, J.
  • Guzmán, J. L.
  • Zarazaga, L. A.
Interest in the preservation of endangered breeds such as the Blanca Andaluza goat, has increased and some steps should be therefore taken to ensure it. The study was designed to determine the seasonal reproductive pattern of Blanca Andaluza bucks, and whether this affects the quality of their semen and its freezability over the year. Seven bucks were used and their body weight, testicular weight, plasma testosterone concentration and fresh sperm quality determined every week. The collected sperm was cryopreserved and stored; it was then thawed and the same sperm quality variables measured every fortnight. High plasma testosterone concentrations were recorded during the summer and autumn, and low concentrations were recorded during winter and spring (p<0.001). No differences were seen between seasons in terms of the percentage of bucks ejaculating, the percentage of active bucks, or ejaculate volume. However, the sperm concentration, the total number of sperm per ejaculate, and the values for most fresh sperm variables were lower during the winter period (at least p<0.05). After freezing-thawing, the quality of winter-collected sperm was better, in some respects, than that of summer-collected sperm (at least p<0.05). These results reveal that Blanca Andaluza bucks show seasonal reproductive activity in terms of their plasma testosterone concentration, but no clear change in their sexual behaviour between seasons was observed. The values of fresh sperm variables also vary over the year, reaching their lowest during winter. However, after freezing-thawing, winter-collected sperm is of overall better quality than sperm collected during the summer. © 2015 INIA.

Evaluation of laboratory assays for the assessment of leaching of copper and chromium from ground-contact wood

  • García-Valcárcel, A. I.
  • Tadeo, J. L.
Laboratory studies were conducted to assess the leaching of Cu and Cr from wood, treated with a Cu-Cr-B preservative, when placed in contact with soil. Two laboratory assays were performed Wood in contact with soil solutions over 30 d, and wood in direct contact with soil over 30 weeks. The influence of several factors, such as soil type and fertilizer use, was studied in both assays. In addition, the effect of soil moisture content and temperature was evaluated when wood was in contact with soil. A discrepancy in the results of the laboratory assays was observed. Leaching of Cu and Cr increased when soil in contact with wood was fertilized, but only an increase of Cu leaching was observed when soil solutions from fertilized soils were used. Moreover, soil solutions from a sandy clay loam soil produced a higher Cu leaching than those from a loamy sand soil, whereas the contrary occurred when treated wood was in direct contact with these soils. In the assay of treated wood in ground contact, the highest metal losses were produced in fertilized soils maintained at constant temperature and high soil moisture content, the latter being the most important factor. These losses were in the range of 5.34 to 15.6% for Cu and 1.85 to 2.35% for Cr in the soils studied. The proposed laboratory assay, using treated wood in direct contact with soil at a moisture content near field capacity during a period of 30 weeks, produced total metal losses that were in accordance with those reported by other authors under field conditions, expressed on a per-year basis. © 2007 SETAC.

mRNA from selected genes is useful for specific detection and quantification of viable Xanthomonas citri subsp. citri

  • Golmohammadi, M.
  • Llop, P.
  • Scuderi, G.
  • Gell, I.
  • Graham, J. H.
  • Cubero, J.
The purpose of this study was to assess the stability of mRNA and rRNA for evaluation of viability for Xanthomonas citri subsp. citri (Xcc). Total RNA from Xcc suspensions subjected to different stress treatments (high temperature or chemical treatment with sodium orthophenylphenate at different concentrations) was extracted at different time periods post-treatment (0, 3, 24 and 48h) and analysed by quantitative real-time reverse transcription PCR (Q-RT-PCR). Primers were designed from selected fragments of rRNA and mRNA from genes involved in bacterial fitness, virulence or general metabolic mechanisms (gumD, rpfB, avrBs2 and gyrB). After stress treatment, only a 445-bp fragment from the gumD mRNA was detected in live Xcc cells specifically, whereas other RNA fragments, as well as DNA targets, were detected in both viable and nonviable cells. Statistical analyses demonstrated that the amount of some transcripts from genes involved in xanthan synthesis, pathogenicity factor regulation and DNA processing was significantly reduced after lethal treatments. The amplification of the 445-bp product from gumD mRNA was demonstrated to be useful for the detection of viable Xcc; the product was detected specifically from viable bacteria on leaf and citrus fruit surfaces and in citrus canker lesions. Instability of long RNA fragments can be used as a practical tool for the study of survival of citrus canker bacteria or for diagnostic purposes when the presence of viable bacteria needs to be confirmed. © 2011 The Authors. Plant Pathology © 2011 BSPP.

Control by ATR-FTIR of surface treatment of cork stoppers and its effect on their mechanical performance

  • González-Adrados, J. R.
  • García-Vallejo, M. C.
  • Caceres-Esteban, M. J.
  • García De Ceca, J. L.
  • González-Hernández, F.
  • Calvo-Haro, R.
Fourier transform infrared (FTIR) spectroscopy was applied to determine the type of surface treatment and dose used on cork stoppers and to predict the friction between stopper and bottleneck. Agglomerated cork stoppers were finished with two different doses and using two surface treatments P (paraffin and silicone), 15 and 25 mg/stopper, and S (only silicone), 10 and 15 mg/stopper. FTIR spectra were recorded at five points for each stopper by attenuated total reflectance (ATR). Absorbances at 1,010, 2,916, and 2,963 cm -1 were obtained in each spectrum. Discriminant analysis techniques allowed the treatment, and dose applied to each stopper to be identified from the absorbance values. 91.2% success rates were obtained from individual values and 96.0% from the mean values of each stopper. Spectrometric data also allowed treatment homogeneity to be determined on the stopper surface, and a multiple regression model was used to predict the friction index (If = Fe/Fc) (R 2 = 0.93). © 2011 Springer-Verlag.

Characterization of a distinctive pattern of periovulatory leptin secretion and its relationship with ovulation rate and luteal function in swine with obesity/leptin resistance

  • Gonzalez-Bulnes, A.
  • Astiz, S.
  • Encinas, T.
  • Gonzalez-Añover, P.
  • Perez-Solana, M.
  • Sanchez-Sanchez, R.
  • Torres-Rovira, L.
  • Tresguerres, J. A. F.
Patterns of leptin secretion during the estrous cycle and the possible relationship of changes in circulating leptin during the periovulatory period with ovarian function in sows of obese (Iberian breed) and lean genotype (Large White × Landrace) were evaluated in two consecutive experiments. Plasma leptin concentrations throughout the estrous cycle in lean sows remain unchanged, but Iberian females showed a periovulatory increase in circulating leptin levels without associated changes in body condition and fatness. In these sows, plasma leptin concentrations at Days -1 and 0 of the cycle were found to be positively correlated with the ovulation rate (r = 0.943 and r = 0.987, respectively; P < 0.05 for both), but the levels of leptin at Day 0 were negatively correlated with the progesterone release from Day 3 (r = -0.557; P < 0.05) and, became more evident at Day 5 of the estrous cycle (r = -0.924; P < 0.005). Such relationships were not observed in the females of the lean genotype. In conclusion, the present study indicates the existence of a distinctive pattern in the periovulatory leptin secretion in swine with obesity and leptin resistance, which is associated with the number and functionality of the corpora lutea present in the subsequent cycle. © 2012 Elsevier Inc.

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