Fluoride Dentifrice Overcomes the Lower Resistance of Fluorotic Enamel to Demineralization

We evaluated if the low resistance of fluorotic enamel to demineralization could be overcome by fluoride dentifrice (FD) treatment. Paired enamel slabs of sound and fluorotic enamel (n = 20/group) from human teeth presenting Thylstrup and Fejerskov index (TF) scores from 0 to 4 were obtained. Half of the anatomic surface of the enamel slabs was isolated and used as a control (baseline) regarding enamel mineralization and fluoride concentration. The slabs were submitted to a pH-cycling model simulating a high cariogenic challenge, and 2×/day they were treated with placebo dentifrice (PD) or FD (1,100 µg F/g, as NaF). After 10 days, the slabs were cut into two halves. Enamel demineralization was evaluated by cross-sectional microhardness in one half, and the fluoride formed (FF) concentration was determined in the other half. For statistical analysis, the data on net demineralization area (ΔΔS) and FF (µg F/g) were grouped into TF0, TF1–2, and TF3–4, and analyzed by two-way ANOVA followed by Tukey’s test (α = 5%). The factors studied were TF (0, 1–2, and 3–4) and dentifrice treatment (PD or FD). The effect of the factors was statistically significant for ΔΔS and FF (p TF1–2 > TF0 (p 0.05) when FD was used. Regarding FF, the groups treated with PD did not differ (p > 0.05), but the greatest (p < 0.05) FF concentration was found in group TF3–4 treated with FD. These findings suggest that the higher susceptibility of fluorotic enamel to demineralization lesions is decreased by the use of FD

Field analysis of the deterioration after some years of use of four insect-proof screens utilized in Mediterranean greenhouses

The installation of insect-proof screens on greenhouse vents is one of the principal methods of protection against harmful insects for crops. Their main disadvantage lies on their negative effects on natural ventilation and greenhouse microclimate, which have been the focus of studies by several authors. However, few works have analysed the effect of accumulated dust and dirt on these screens. The present study has analysed four anti-insect screens, comparing their geometric characteristics before installation and after three to four years of use. Two negative effects have been observed and quantified: deterioration of the threads that make up the screen and reduction of porosity due to accumulated dirt in the pores. This deterioration over time gives leads to a mean increase in thread diameter of 3.1%, as well to a mean decrease in the pore size of 6.2% and 2.3% in the weft (Lpx) and the warp (Lpy), respectively. In fact, the insect-proof screen porosity (φ) decreased due to the deterioration of the threads by an average of 6.5%, in addition to an average 20.3% reduction due to the accumulation of dirt in the pores, making a total reduction in porosity of 26.8%. This decrease in porosity leads to lower greenhouse ventilation rates, and is therefore detrimental for the greenhouse microclimate. Consequently, it is recommended that insect-proof screens in arid areas such as Almería (Spain), with abundant dust suspended in the atmosphere, be washed monthly using water sprayed at high pressure

LOS PORIFEROS DE LA PROVINCIA DE ALICANTE (ESPANA)

A total of 36 species of Porifera have been found in some localities of the coast of Alicante, southeastem of Spain, from O to 50 m deep. Adreus fascicularis (Bowerbank, 1866) is new for the mediterranean coast, Samus anonyma Gray, 1867 for the Iberian Peninsula, and 24 of them for the Alicante province.Se han encontrado 36 especies de esponjas en muestreos realizados en la provincia de Alicante, sudeste de España. La axinélida Adreus fascicularis (Bowerbank, 1866) se cita por primera vez para el Mediterráneo y Samus anonyma Gray, 1867, es primera cita para la península ibérica

Discrete breathers in dissipative lattices

We study the properties of discrete breathers, also known as intrinsic localized modes, in the one-dimensional Frenkel-Kontorova lattice of oscillators subject to damping and external force. The system is studied in the whole range of values of the coupling parameter, from C=0 (uncoupled limit) up to values close to the continuum limit (forced and damped sine-Gordon model). As this parameter is varied, the existence of different bifurcations is investigated numerically. Using Floquet spectral analysis, we give a complete characterization of the most relevant bifurcations, and we find (spatial) symmetry-breaking bifurcations which are linked to breather mobility, just as it was found in Hamiltonian systems by other authors. In this way moving breathers are shown to exist even at remarkably high levels of discreteness. We study mobile breathers and characterize them in terms of the phonon radiation they emit, which explains successfully the way in which they interact. For instance, it is possible to form ``bound states'' of moving breathers, through the interaction of their phonon tails. Over all, both stationary and moving breathers are found to be generic localized states over large values of $C$, and they are shown to be robust against low temperature fluctuations.Comment: To be published in Physical Review

Effects of Extending Milk Replacer Feeding during the Fattening Period on the Behaviour and Welfare of Lambs: A Preliminary Study

There is a lack of information on the behavioural and welfare effects of sustaining artificial milk feeding in fattening lambs. Therefore, the present work aimed to study the effects of prolonged artificial milk feeding during fattening with a high concentrate diet on the behaviour of lambs. The behaviour of 16 non castrated male lambs of the Manchega sheep breed (eight lambs were in the group that were fed daily a bottle of milk, and the other eight were in the weaned group) was recorded with four fixed cameras just before bottle feeding (~8:30 a.m.) of the unweaned group till four hours later, every day for 7 weeks. The solid diet (pelleted concentrate plus cereal straw) and housing conditions were the same in both groups. Solid feeds were offered ad libitum. There were no differences between groups in time spent eating nor in drinking, playing, scratching and oral activity behaviours (p > 0.05), but resting episodes were longer in weaned lambs (p < 0.05). Weaned lambs presented a higher frequency of self-grooming behaviour (p < 0.05), while the unweaned group performed a higher frequency of interaction behaviour (p < 0.05). In conclusion, the behaviours of lambs that were fed daily a bottle of milk during the fattening period did not substantially differ from the weaned individuals

Adding plant oils to dairy goat diets: Effect on fatty acid content of milk fat

[ES]: El objetivo del presente trabajo fue investigar el efecto de la adición de aceites vegetales de diferente grado de insaturación a la dieta de cabras lecheras sobre el perfil de ácidos grasos de la grasa láctea. Doce cabras de raza Malagueña fueron asignadas al azar a uno de cuatro tratamientos: dieta basal sin aceite añadido y la misma dieta basal adicionada con 48 g/d de aceite de girasol alto oleico, aceite de girasol normal o aceite de lino. La dieta estuvo compuesta por heno de alfalfa (30%) y un concentrado granulado (70%) en el que se incluyó el aceite correspondiente. Todos los aceites redujeron el contenido de ácidos grasos saturados de cadena media de la grasa láctea (P 0,05). El aceite de girasol normal incrementó el contenido de los ácidos C18:1t10, vaccénico y ruménico y aumentó el valor de la ratio linoleico/α-linolénico (P 0,05). Los resultados obtenidos permiten concluir que la adición de aceite de lino a la dieta de cabras en lactación, en comparación con la de los aceites de girasol alto oleico y normal, modifica el perfil de ácidos grasos de la grasa láctea en un sentido más favorable desde el punto de vista de la salud humana.[EN]: The aim of this study was to investigate the effects of adding differently unsaturated vegetable oils to a dairy goat diet on fatty acid content of milk fat. Twelve Malagueña goats were randomly allocated to one of four treatments: no oil basal diet and the same basal diet supplemented with 48 g/d of high oleic sunflower oil, regular sunflower oil or linseed oil. The basal diet was made of alfalfa hay and a pelleted concentrate (30:70 w/w). The concentrate included the respective oils. Supplemented diets decreased medium chain saturated fatty acid content in milk fat (P 0.05). Regular sunflower oil increased C18:1t10, vaccenic and rumenic acid contents as well as linoleic to α-linolenic acid ratio (P 0.05). It was concluded that compared to high oleic o regular sunflower oils, adding linseed oil in dairy goat diets modifies milk fat fatty acid content more favourably from the point of view of human health.Peer Reviewe

Measurement of the Fermi Constant by FAST

An initial measurement of the lifetime of the positive muon to a precision of 16 parts per million (ppm) has been performed with the FAST detector at the Paul Scherrer Institute. The result is tau_mu = 2.197083 (32) (15) microsec, where the first error is statistical and the second is systematic. The muon lifetime determines the Fermi constant, G_F = 1.166353 (9) x 10^-5 GeV^-2 (8 ppm).Comment: 15 pages, 6 figure

Plasmin activity in Manchega ewe milk: The effect of lactation, parity and health of the udder, and its influence on milk composition and rennet coagulation

Milk from 40 Manchega ewes was collected monthly and analysed during a complete lactation (5 months). Milk samples were classified by their origin in 3 categories, termed PR (primiparous ewes), M1 (multiparous ewes with no damage of the udder in the previous lactation) and M2 (multiparous ewes with udder damage in the previous lactation). The influence on plasmin of several factors as stage of lactation, parity, somatic cell count and udder health status was studied, as well as the effect of plasmin activity on milk composition and rennet coagulation. Plasmin activity decreased throughout lactation but was not affected by parity or somatic cell count (P > 0.05). A strong negative correlation was found between plasmin activity and protein (especially casein), presumably due to the proteolysis of ß-casein. Plasmin also worsened rennet coagulation, increasing rennet clotting time (RCT) and negatively affecting curd firmness (A60), especially in multiparous ewes. However, the good health condition in the herd may have camouflaged some effects of plasmin over renneting

Characterization of minimal lesions related to the presence of visna/maedi virus in the mammary gland and milk of dairy sheep

[EN] Background: In order to characterize the complete range of lesions, especially minimal, affecting mammary gland and viral antigen distribution and target cells using immunohistochemistry in naturally Visna/maedi (VM) 84 infected sheep were studied, forty-four from flocks with clinical cases (A) and 35 randomly sampled from two abattoirs (B) together with five negative controls (C). An immunocytochemistry technique was developed and further milk samples (n = 39) were used to study viral excretion, carrier cells and the role of milk and colostrum in the transmission of the disease. Results: All sheep from group C and three sheep from group B were negative to VM in tissue sections by histopathology, immunohistochemistry and PCR, and also in serum using ELISA. Several degrees of CD3 + lymphocytic interstitial mastitis were observed in groups A and B: minimal (+) n = 26 sheep; moderate (++), n = 32 and severe (+++), n = 12. No differences in lesion distribution were observed between groups A and B. Viral presence was confirmed by immunohistochemistry using two different antibodies and/or PCR in every tissue with lesions while serology was negative in six sheep with lesions. Two milk samples taken from milk tanks from two flocks from group A and fourteen milk samples from 29 infected sheep from group B were positive to VM (most of them from animals with moderate and severe lesions). Positivity was only found in macrophages, even in focal and minimal lesions, while no positivity was observed in epithelial or any other cells in either tissue and milk samples. Conclusions: This new observation of the minimal lesions described in this work increased the prevalence of VM lesions in mammary gland up to 90.9% and VM should be considered as a differential diagnosis when minimal interstitial lesions are detected. A high prevalence of VM was observed in intensive milk-producing sheep, ELISA serology did not detect as positivity all infected animals, while histology, IHC or PCR showed higher sensitivity. The cytological technique developed was very useful in milk-cell studies using hematoxylin and eosin and immunocytochemistry. Viral detection in milk samples (16/39) confirms a potential but limited role of milk/colostrum in viral transmissionSIThis work was supported by LE361A12–1 project of Castilla y León Government and FPU13/01081 grant of the Spanish Government. LE361A12– 1 project financed the materials necessary for collection, analysis and interpretation of data. FPU13/01081 grant financed the pre-doctoral contract of the main performer of experiments and manuscript writer E

Influence of Dietary Algae Meal on Lipid Oxidation and Volatile Profile of Meat from Lambs with Competent Reticular Groove Reflex

Dietary lipid sources influence intramuscular fatty acid composition, which in turn may affect the volatile profile of meat. The aim of this work was to investigate the effects of marine algae supplementation (Aurantiochytrium limacinum) on volatile compounds of cooked lamb meat. Forty-eight lambs with 42 days of age were divided into three groups: lambs fed a conventional diet without algae meal supplementation (NOALG), lambs with competent reticular groove reflex (RGR) fed the same diet supplemented with 2.5% marine algae meal mixed in the concentrate (ALGCON), and lambs with competent RGR, receiving the same diet and fed with 2.5% marine algae meal in a milk replacer to bypass the rumen (ALGMILK). Lipid and protein oxidation in raw meat was assessed and volatile compounds in grilled meat were determined. The highest and lowest lipid oxidations were observed in the ALGMILK and NOALG groups, respectively. Protein oxidation was unaffected. Out of 56 identified compounds, 12 volatiles significantly increased in both algae groups and 6 of them exclusively in the ALGCON treatment. Algae meal supplementation and its form of administration, either protected or not from rumen degradation, are important factors to consider in lipid oxidation and the aromatic profile of lamb meat