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Some traits of potato tubers can affect their quality, contributing to potential acrylamide formation in chips. Using three potato cultivars with contrasting dry biomass and reducing sugar contents, the effects of nitrogen source and storage conditions on tuber non-structural carbohydrate and free amino acid contents were evaluated. Color and acrylamide precursors formation were also evaluated. Cultivars presented their own characteristics for accumulation of sugars and free amino acids, the nitrogen source having only a minor effect on carbohydrates and amino acids contents. Starch mobilization and free amino acid accumulation occurred in all cultivars, but one presented the greatest sugars contents after cold storage. In general, tubers having the greatest sugar and amino acids contents also presented color alteration in chips and greatest acrylamide content. Selecting potato cultivars with lower sugars content and sensitivity to cold storage could be strategies to reduce contents of acrylamide precursors in tubers that decrease chips quality. Algunos rasgos de los tubérculos de papa pueden afectar a su calidad, contribuyendo a la formación potencial de acrilamida en patatas fritas. Usando tres variedades de papa con diferente biomasa seca y contenido de azúcares reductores, fueron evaluados los efectos de las fuentes de nitrógeno y las condiciones de almacenamiento sobre los carbohidratos no estructurales y los contenidos de aminoácidos libres de los tubérculos. El color y la formación de precursores de acrilamida fueron también evaluados. Las variedades presentaron sus propias características de acumulación de azúcares y aminoácidos libres, mientras que la fuente de nitrógeno tuvo sólo un efecto limitado sobre los carbohidratos y contenidos de aminoácidos. La movilización del almidón y la acumulación de aminoácidos libres se produjeran en todas las variedades, pero una presentó los mayores contenidos de azúcares después de almacenamiento en frío. En general, los tubérculos que tuvieron los mayores contenidos de azúcares y aminoácidos también presentaron devaluación del color en las patatas fritas, y mayor contenido de acrilamida. La selección de variedades de papa con menores concentraciones de azúcares y sensibilidad al almacenamiento en frío podrían ser estrategias para disminuir los contenidos de precursores de acrilamida en tubérculos, lo cual degrada la calidad de las patatas fritas.

De nombreux programmes internationaux visant la réduction du tabagisme chez les jeunes sont réalisés en milieu scolaire, permettant de suivre les interventions sur plusieurs années. Les approches prometteuses préconisent de mettre en place la prévention tabac durant toute la scolarité et sur le temps scolaire. Plusieurs études indiquent aussi qu’une initiation précoce aux substances psychoactives est un fort prédicteur de l’addiction à l’âge adulte. Ce constat nous a conduit à mettre en place en 2014 un programme éducatif expérimental (PEPITES) dès la 6eet jusqu’en 3epour réduire l’expérimentation du tabac et le tabagisme ultérieur.

Factors such as durability and performance must be the guideline in the design of any building, since most of the pathological manifestations that affect the buildings are associated with construction stages, from project design to use of the structure, severely influencing the useful life of structure. This work aims to diagnose the pathological manifestations of the current reinforced concrete structures in the urban environment, through a case study. The inspections were carried out in an anonymous non-completed building in Patos de Minas (MG), with an estimated age of 28 years. It was carried out the diagnosis of the main pathological manifestations and prognosis of the analyzed system. It used to inspections in the field—visual and detailed—and laboratory tests, such as measurement of propagation velocity of ultrasonic waves, reinforcement locate (scan), rebound hammer test, compressive strength test, Brazilian disk test, capillary water absorption test and carbonation depth measurement test. The pathological manifestations found in the concrete structure analyzed were cracking, peeling, carbonation and reinforcement corrosion. The value of rebound and ultrasonic pulse velocity obtained were relatively high (around 58 rebound and velocity of 4000 m/s), due to advanced carbonation (average across 30 mm). Already water absorption by capillary found in the laboratory was high too (in the range from 6105.17 to 30181.64 g/m2). Due to the high degree of deterioration, corrective or recovery measures are not applicable.

Aims.We investigate evidence of accretion in a sample of 15 Herbig Ae/Be stars to determine whether these events originate in a remnant gaseous structure from the primordial cloud (rich in hydrogen) or in a metal-rich body (like comets in our Solar System). During such analysis we also determine precise stellar parameters for this sample of stars.

The DOHaD research field has successfully associated adult non-communicable diseases with inadequate nutrition in early periods of life. More recently, different types of exposure have been linked with impaired developmental outcomes and later health consequences, such as cesarean section at delivery, air pollution and domestic violence during pregnancy. The aim of this work is to bring up this issue looking at the published evidence on these three highly prevalent hazards in Latin American countries.

Two experiments using soybean meal (SBM) or canola meal (CM) were conducted to investigate whether the choice of digestibility marker influenced the apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of N and AA in diets supplemented with phytase. In each experiment, 18 barrows fitted with T-cannulas at the ileocecal junction were assigned to 3 diets consisting of a N-free diet to determine endogenous losses of N and AA, a semipurified diet (SBM in Exp. 1 or CM in Exp. 2), and the semipurified diet supplemented with phytase at 1,000 phytase units/kg. Three digestibility markers including acid-insoluble ash (AIA), chromic oxide (Cr2O3), and titanium dioxide (TiO2) were added to each diet at 3 g/kg. Each diet was fed for 7 d, consisting of a 5-d adjustment and a 2-d collection of ileal digesta. In both studies, basal ileal endogenous losses determined with Cr2O3as a digestibility marker were lower (P< 0.01) than with those determined with AIA or TiO2digestibility markers. Using SBM as the protein source in Exp. 1, there was no interaction between phytase and digestibility marker on AID or SID of AA. The AID of N and AA in SBM using AIA as a digestibility marker tended to be lower (P< 0.1) compared with Cr2O3or TiO2digestibility markers. Phytase supplementation increased (P< 0.001) the AID of Ca and P. The use of AIA or Cr2O3digestibility marker tended to be associated with lower (P< 0.1) SID values compared with TiO2. Phytase did not affect the SID of N or any AA in SBM except for Met, for which there was an increase (P< 0.05) with phytase supplementation. Using CM as the protein source in Exp. 2, there were significant interactions between digestibility marker and phytase. Phytase supplementation had effects (P< 0.01) on AID or SID when Cr2O3or TiO2was used as the digestibility marker. With Cr2O3or TiO2as the digestibility marker in the CM diets, phytase supplementation increased (P< 0.05) the SID of N and all AA (except Trp). There was no SID of N or AA response to phytase supplementation of CM when AIA was used as a digestibility marker. In contrast, there were no clear improvements in AA digestibility from phytase supplementation for SBM. Phytase effects on AID or SID of AA were dependent on the digestibility marker used in diets when CM was used as the protein source but not when SBM was used as the protein source. Therefore, AA digestibility response to phytase supplementation may depend on the protein being evaluated as well as the choice of digestibility marker.

Nanostructuring boron-doped diamond (BDD) films increases their sensitivity and performance when used as electrodes in electrochemical environments. We have developed a method to produce such nanostructured, porous electrodes by depositing BDD thin film onto a densely packed “forest” of vertically aligned multiwalled carbon nanotubes (CNTs). The CNTs had previously been exposed to a suspension of nanodiamond in methanol causing them to clump together into “teepee” or “honeycomb” structures. These nanostructured CNT/BDD composite electrodes have been extensively characterized by scanning electron microscopy, Raman spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Not only do these electrodes possess the excellent, well-known characteristics associated with BDD (large potential window, chemical inertness, low background levels), but also they have electroactive areas and double-layer capacitance values ∼450 times greater than those for the equivalent flat BDD electrodes.

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Regions with steep dose gradients are often encountered in clinical x-ray beams, especially with the growing use of intensity modulated radiotherapy (IMRT). Such regions are present both at field edges and, for IMRT, in the vicinity of the projection of sensitive anatomical structures in the treatment field. Dose measurements in these regions are often difficult and labour intensive, while dose prediction may be inaccurate. A dedicated algorithm developed in our institution for conversion of pixel values, measured with a charged coupled device camera based fluoroscopic electronic portal imaging device (EPID), into absolute absorbed doses at the EPID plane has an accuracy of 1–2&percent; for flat and smoothly modulated fields. However, in the current algorithm there is no mechanism to correct for the (short-range) differences in lateral electron transport between water and the metal plate with the fluorescent layer in the EPID. Moreover, lateral optical photon transport in the fluorescent layer is not taken into account. This results in large deviations (>10&percent;) in the penumbra region of these fields. We have investigated the differences between dose profiles measured in water and with the EPID for small heavily peaked fields. A convolution kernel has been developed to empirically describe these differences. After applying the derived kernel to raw EPID images, a general agreement within 2&percent; was obtained with the water measurements in the central region of the fields, and within 0.03 cm in the penumbra region. These results indicate that the EPID is well suited for accurate dosimetric verification of steep gradient x-ray fields.

Abstract:: The experimental study of the low temperature (down to 0.4 K) specific heat of the Kondo ferromagnet system Ce1-xYxNi0.8Pt0.2 is presented. Special attention has been paid to the Ce0.8Y0.2Ni0.8Pt0.2 composition, which is situated near the Zero Temperature Phase Transition. This compound presents a marked divergence of the specific heat at low temperatures, signature of a Non Fermi Liquid behaviour. Different frameworks which could account this behaviour are analysed, being the most plausible a “strong coupling” situation with disorder effects. The importance of these effects is discussed in the general scenario of the Non Fermi Liquid compounds considering the differences between “ligand” and “Kondo hole” systems.

We report on the measurement of multiple Andreev resonances at atomic size point contacts between two superconducting nanostructures of Pb under magnetic fields higher than the bulk critical field, where superconductivity is restricted to a mesoscopic region near the contact. The small number of conduction channels in this type of contacts permits a quantitative comparison with theory through the whole field range. We discuss in detail the physical properties of our structure, in which the normal bulk electrodes induce a proximity effect into the mesoscopic superconducting part.

The Autoset autotitration system (Resmed, Australia) was designed as an aid for determination of the effective level of CPAP. Two studies have shown that the 95% pressure centile during a night with Autoset, after excluding any periods with severe leak (P95), was well correlated with the pressure determined manually according to the reference method. However, the suitability of P95 under Autoset for treatment with conventional CPAP needed to be evaluated outside of the context of titration. The objective of this study was to measure the compliance and efficacy of CPAP at P95 determined by Autoset, after 3 months. Twenty-four patients who had undergone routine autotitration by Autoset under polysomnographic control in the laboratory for previously untreated OSAS were evaluated after 3 months of treatment with CPAP at P95. This evaluation was based on compliance, daily usage, determined by reading the hourly counter, Epworth sleepiness score and home respiratory recording under CPAP. Polysomnography under Autoset showed a significant reduction of abnormal respiratory events (apnea-hypopnea index (AHI): 5.7 (+/-4.6) vs 69.6 (+/-29.8) n/h; p<0.001). P95 was between 8.5 and 15 cm H2O (mean: 11.2 (+/-1.6)). Two patients were lost to follow-up. At 3 months, 18 out of 22 (82%) patients declared that they were still using their machine with a daily usage of 5.25 (+/-1.82) h. The Epworth sleepiness scale was significantly decreased (5 (+/-4.1) vs 11.4 (+/-5.4); p<0.05). P95 recommended by Autoset remained effective on abnormal respiratory events with a low AHI (4.1 (+/-3.2) n/h) and a low 4% oxygen desaturation index (3.6 (+/-4.5) n/h) under CPAP. This study confirms the efficacy of autotitration and the suitability of P95 determined by Autoset for long-term treatment by conventional CPAP at home.

Spatial variability of 1,280 field‐measured infiltration rates on Yolo loam (fine‐silty, mixed, nonacid, thermic Typic Xerorthents) was studied using geostatistical concepts. The measurements were made at the nodes of an irregular grid consisting of 160 rows and eight columns. Sample spacing within columns was 1 m. Columns were spaced irregularly at 1, 5, 15, and 19 m. A variogram for the 1,280 measurements was used to krige 800 additional values within five more columns and to draw a contour map of the area. The large number of measured values made it possible to calculate the minimum number of samples necessary to reproduce the infiltration rate measurements with a fairly large approximation. As a result, it could be concluded that a minimum of 128 samples was enough to obtain nearly the same information as with 1,280 samples. A suggestion on how to use autocorrelograms in sampling schemes is presented.

Abstract: The formation of polytypic modifications is observed in dislocation-free silicon single crystals under directional plastic deformation. It is shown that the deformation-stimulated phase appears on the surface of the sample in the form of small grains ranging from several hundred to several thousand angstroms in size. A twin structure in the individual grains is observed.

Y-type Langmuir−Blodgett films of the octasubstituted amphiphilic phthalocyanines 1 and 2 deposited onto hydrophobic glass have been investigated by atomic force microscopy (AFM). The technique has been used to measure the thicknesses of one, two, and three bilayer films, and the results show that each bilayer is of the same thickness. This characteristic thickness is the same as the repeat spacing measured using low-angle X-ray diffraction methods on thicker samples, and thus we demonstrate that the order of the molecules in the monolayers after several cycles of deposition remains constant. We have detected considerable differences with respect to the consistency of the films of 1 and 2 and their resistance to the pressure exerted by the AFM tip during the scanning process required to obtain the images. Films of 1 are more robust and we have observed the columnar arrangement of the molecules at the surfaces of one, two, and three bilayers. However, under the same imaging conditions it was not possible to observe molecular order before perturbing the surface of the films formed by 2. The lateral extent of the ordered regions at the surfaces of the films of 1 covers areas of at least 10 μm². There is very clear evidence that there is a predominant alignment. Inspection of 82 images taken of different regions of the film indicates that ca. 83% show columns whose axes are aligned to within ±30° of the dipping direction.

Simultaneous measurements of the electrical resistivity ? Seebeck coefficientS, and thermal conductivity k of URu2Si2 and UBe13 are carried out. For URu2Si2 a strong anomaly in the k(T) dependence near the temperature of the antiferromagnetic transition was observed. The thermal conductivity of UBe13 exhibits only a small (about 30%) change of the derivativedk/dT near 8–9 K, which may be related to an increase of the characteristic length of antiferromagnetic correlations below this temperature. Studying STM spectra in the normal and magnetic phase of a URu2Si2 single crystal we observed that the magnetic gap, partially opened at the Fermi surface below the Néel temperature,TN=17.5 K, is strongly anisotropic: gapped states mainly correspond to the tetragonalab-plane. Anisotropy of the upper critical field nearTc(H<4kOe), studied for URu2Si2 and UBe13 single crystals, was found to be in a good correspondence with the character of the antiferromagnetic transition.

Experimental results on the low temperature variation of spontaneous polarization in several ferroelectrics (TGS, BaTiO3, LiNbO3 and KDP) are presented. These results are the abject of a theoretical discussion, in the light of a slightly modified version of a model recently proposed by one of us.

Measurements of the charge released (ΔQ > 0) by crystalline samples of ferroelectric NaNO2 at low temperatures show a temperature dependence of type Q/A = aTa + bT4 + ce-θ/T. The first term is weak and ill defined in the temperature range examined. The other two terms are very well established experimentally. The second (negative) term can be associated with the secondary pyroelectric coefficient, and the third one (positive) is analogous to exponential terms observed in various other ferroelectrics at low T, which are interpretable as due to low lying optical modes. A change in sign of the total pyroelectric coefficient, similar to that observed in KDP and other materials, is observed at 40 K.

An electrostriction cell has been built up in order to get direct measurement of piezoelectric coefficients. This cell is a modified version of the three terminal capacitance cell for thermal expansion measurements developed in our laboratory. Several improvements have been introduced resulting in a noticeable increase in the system's mechanical stability. The requirements on the sample's size along the electrical applied field direction allow the use of speciments about 2mm thick.

Low temperature heat capacity measurements (0.6

Results on the piezoelectric deformation coefficient of three commercial PZT ceramics at zero frequency and for different temperatures are presented in this communication. We study the phenomenon of "creep" in these materials at different temperatures and the dependence of the deformation coefficient on the applied field for two of the samples.

We report on the low temperature specific heat measurements for different sized KTaO3 crystals. Results for (1) a high quality macroscopic single crystal (300 mm3), (2) an assembly of crystallites with 1 mm average diameter and (3) a 1μm average diameter powder are discussed.

We have measured the specific heat of a very pure BaTiO3 single crystal using a modified relaxation method which includes the use of a sin gle germanium chip for heater and thermometer. The measurements are made in interaction with a desk controller which allows for relaxation times below 0.5 s. The sample is a single crystal of 718mg. which was grown from suprapure product by the Czochrzlsky method. Our results follow a pure T3 dependence of the specific heat in the temperature range 3-10K showing no anomalous extra contribution. This is in contradiction with a general T3/2 term in the specific heat of ferroelectrics in the range 2K-10K, but extrapolates smoothly with unpublished results at lower temperatures.

AbstractWe have developed two instrumental arrangements for the measurement of low-temperature specific heat and thermal conductivity of molecular glasses and crystals, which are liquid at ambient temperature. We present measurements carried out with ethanol (CH3CH2OH). Ethanol is an organic low-molecular-weight substance, which exhibits polymorphism. There are three different phases at low temperature: a stable monoclinic crystal, a conventional structural glass, and an orientational glass produced by supercooling a plastic crystalline state. Fully-deuterated ethanol (CD3CD2OD) has also been studied. The specific heat Cp(T) and the thermal conductivity κ(T) of several crystalline and glassy states of ethanol have been measured in the temperature range from around 2 K up to 30 K. All structural and orientational glassy states show the so-called “anomalous”thermal properties of common inorganic glasses.

The thermal expansion of polycrystalline ortho-terphenyl has been measured in the range 9 K ˇ- T ˇ- 30K. A strong lattice contraction occurs for most temperatures in this range. The microscopic origins of such anharmonic effects are discussed on qualitative grounds on the basis of recent Raman measurements. the relevance of the present findings for glassy dynamics are also addressed.