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With the proposed ban on antibiotic growth promoters it is becoming increasingly important to provide diets to young pigs which enhance the long term health. Alternative strategies to promote health include organic acids, herbal products and natural antioxidants. These products have various proposed modes of action including improved liver function, removal of reactive oxygen species and the enhancement of the immune function. The objective of this experiment was to measure the effect of a commercial herbal mixture and Lycopene on the performance and immune function of weaned pigs.
Selection for efficiency of lean growth has lead to a marked reduction in fat gain and voluntary food intake (VFI) of modern genotypes. There is concern that future improvements in lean growth rate may be limited by appetite. Moreover, the ability of lean genotypes to adjust their VFI in response to variations in nutrient density is not well known. Such genotypes may fail to compensate their intake in response to marginal reductions in nutrient density, which could affect growth performance. The aim was to evaluate the VFI and growth performance of ‘White’ and Meishan cross growing pigs in response to incremental reductions in dietary energy content.
Non-starch polysaccharide (NSP) content of barley is predominately in the form of β-glucan, whereas in wheat it is predominately pentosans (containing the sugars arabinose and xylose). It has generally been accepted therefore that a high level of β-glucanase is needed in broiler diets containing barley, whereas wheat based diets require a high level of endoxylanase. Trials have however previously suggested that including an endoxylanase based enzyme in broiler diets will perform at least as well as enzyme containing highlevels of β-glucanase in diets containing up to 30% barley. To confirm this finding, a trial was initiated at Roslin Institute, Edinburgh to compare the effectiveness of Natugrain Blend 66% (an endoxylanase based product) against Natugrain 33% (endoxylanase/β-glucanase product) in diets containing up to 30% barley.
Previous research has indicated that biological older brothers increase the odds of androphilia in males. This finding has been termed the fraternal birth order effect. The maternal immune hypothesis suggests that this effect reflects the progressive immunization of some mothers to male-specific antigens involved in fetal male brain masculinization. Exposure to these antigens, as a result of carrying earlier-born sons, is hypothesized to produce maternal immune responses towards later-born sons, thus leading to female-typical neural development of brain regions underlying sexual orientation. Because this hypothesis posits mechanisms that have the potential to be active in any situation where a mother gestates repeated male fetuses, a key prediction is that the fraternal birth order effect should be observable in diverse populations. The present study assessed the association between sexual orientation and birth order in androphilic male-to-female transsexuals in Brazil, a previously unexamined population. Male-to-female transsexuals who reported attraction to males were recruited from a specialty gender identity service in southern Brazil (n=118) and a comparison group of gynephilic non-transsexual men (n=143) was recruited at the same hospital. Logistic regression showed that the transsexual group had significantly more older brothers and other siblings. These effects were independent of one another and consistent with previous studies of birth order and male sexual orientation. The presence of the fraternal birth order effect in the present sample provides further evidence of the ubiquity of this effect and, therefore, lends support to the maternal immune hypothesis as an explanation of androphilic sexual orientation in some male-to-female transsexuals.
First results on formation of thin film GeOI structures by the Smart Cut™ technology are presented in this paper. Thin single crystal layers of Ge have been successfully transferred, via oxide bonding layer, onto standard Si substrates with diameters ranging from 100 to 200 mm. Compared to SOI manufacturing, the development of GeOI requires adaptation to the available germanium material, since the starting material can be either bulk Ge or an epitaxial layer. Some results will be presented for GeOI formation according to the different technological options. Germanium splitting kinetics will be discussed and compared to already published results. To show good quality of the GeOI structures, detailed characterization has been done by TEM cross sections for defect densities, interfaces abruptness and layers homogeneities evaluation. AFM was used for surface roughness measurements. These results help define procedures that are required to achieve large diameter high quality GeOI structures.
Strained Silicon On Insulator wafers are today envisioned as a natural and powerfulenhancement to standard SOI and/or bulk-like strained Si layers. For MOSFETs applications, thisnew technology potentially combines enhanced devices scalability allowed by thin films andenhanced electron and hole mobility in strained silicon. This paper is intended to demonstrate byexperimental results how a layer transfer technique such as the Smart Cut™ technology can be usedto obtain good quality tensile Strained Silicon On insulator wafers. Detailed experiments andcharacterizations will be used to characterize these engineered substrates and show that they arecompatible with the applications.
Ion mixing of FeNi-Si multilayers is performed at the same dose of 3.1015 Xe+ cm−2 with either of the three energies 200, 300 or 400 keV. The irradiation is done at liquid nitrogen temperature (LNT) or at room temperature (RT). The mixed layers are characterized by reflection high energy electron diffraction (RHEED), transmission electron microscopy (TEM), Rutherford backscattering (RBS), secondary ion mass spectroscopy (SIMS) and ferromagnetic resonance (FMR). Films made at 400 keV are more reproducible and as homogeneous as the best amorphous films realized up to now, using sputtering techniques.
Nanocrytslline composite films of Ag-Mo and Ag-Ni have been made by a co-deposition technique in UHV. The structure and composition have been studied by x-ray diffraction (XRD), transmission electron microscopy (TEM), and electron probe microanalysis (EPMA). For practical applications, the friction coefficient and wear rate were measured using a pin-on-plate machine for Ag-Mo composites deposited on steel. For fundamental studies, the hardness of the Ag-Ni composites deposited on oxidized Si wafers was measured using a nanoindenter. Experiments show that (1) reduction of friction and wear rate can be achieved using these nanocomposite coatings and (2) the hardness of the nanocomposites depends on the grain size. As the grain size of the Ag decreases from 100 to 10 nm, the hardness increases about 4 times.
P+NN+ silicon rectifiers have been irradiated by protons and alpha particles. DLTS and reverse recovery time (the so called TRR) measurements were performed in both as-irradiated and annealed (400°C) samples. The evolution of implantation induced-centers with the annealing is not the same when using the two particles. For example, the concentration of the well known A center increases (decreases) with the annealing when protons (alpha particles) are used. On the other hand, the measurements of the TRR show that the rectifier speed decreases with the annealing in all cases studied.
Highly transparent films with tailorable sheet resistivity were prepared by ion-beam sputtering of indium tin oxide (ITO) with MgF2 or SiO2 in the presence of high-purity air. Sheet resistivities of 103−101 ohms/square (ω/–) and visible transmittances as high as 92% (not corrected for substrate absorption) were obtained in films ∼30 nm thick. Resistivity increased by as much as two orders of magnitude in the first year after preparation; however, thicker films (e.g. 80 nm) were much more stable but somewhat less transparent. Preliminary data from exposure of film samples to atomic oxygen in a plasma asher indicate minimal degradation in optical properties. Heat-treating pure ITO in air produced transparent, slightly conductive films but with poorer stability of sheet resistivity in air than co-deposited ITO with either SiO2, or MgF2. Electrical transport measurements yielded new information on the electronic properties of ITO and related materials. These films show promise as low-absorption static bleedoff coatings for space photovoltaic arrays as well as CRT faceplates and other commercial applications.
Direct nitridation of the silicon substrate using gaseous NO at 550–700°C, 10 mbar is studied using physical (SIMS, TEM, XPS) and electrical characterisations. The nitrogen profile can be tailored for the fabrication of thin nitrided oxides as in the case of implanted nitrogen. Degradation of the I(V) characteristics has been evidenced when the nitrogen amount increases.
We have grown a variety of isolated GaN nanowires using gas-source molecular beam epitaxy (MBE) and characterized their structural and optical properties. The nanowires have demonstrated a number of promising materials characteristics, including low defect density and high luminescent intensity. Well-separated nanowires formed spontaneously on Si(111) substrates after deposition of a thin AlN buffer layer. Metal catalysts were not used. X-ray diffraction indicates that the c and a lattice parameters are within 0.01 % of the lattice parameters of bulk GaN. Transmission electron microscopy (TEM) revealed the nanowires to be free of dislocations and stacking faults, although a GaN matrix layer growing at the base of the wires was found to have a high density of basal plane stacking faults. The room temperature photoluminescence (PL) intensity compared favorably with a free-standing, thick film of high quality GaN. Several features of the low temperature PL spectra also indicated that the nanowires had few structural defects or chemical impurities. Finally, electrical characterization of dispersed nanowires demonstrated that efficient electrical contacts could be made and that the resistivity of the nanowires was comparable to that of bulk material.
A homogeneously mixed phase of carbon and 10% nickel yielding amorphous carbon-nickel composite (a-C-Ni) films is prepared by an excimer UV pulsed laser ablation. Conductivity study of these films shows a nearly activated conduction. Also a saturation of conductivity below a temperature of 25 K explains the presence of an additional density of states at the Fermi level in these samples. Our experiments demonstrate a very different behaviour of electronic properties of these novel materials compared to undoped diamond-like carbon (DLC) films, which was directly confirmed using valence band spectroscopy.
Florida is the fourth largest state in the United States of America. In 2004, 218,045 live babies were born in Florida, accounting for approximately 1744 new cases of congenital heart disease. We review the initial experience of The Society of Thoracic Surgeons Congenital Heart Surgery Database with a regional outcomes report, namely the Society of Thoracic Surgeons Florida Regional Report.
Eight centres in Florida provide services for congenital cardiac surgery. The Children’s Medical Services of Florida provide a framework for quality improvement collaboration between centres. All congenital cardiac surgical centres in Florida have voluntarily agreed to submit data to the Society of Thoracic Surgeons Database. The Society of Thoracic Surgeons and Duke Clinical Research Institute prepared a Florida Regional Report to allow detailed regional analysis of outcomes for congenital cardiac surgery.
The report of 2007 from the Society of Thoracic Surgeons Congenital Heart Surgery Database includes details of 61,014 operations performed during the 4 year data harvest window, which extended from 2003 through 2006. Of these operations, 6,385 (10.5%) were performed in Florida. Discharge mortality in the data from Florida overall, and from each Florida site, with 95% confidence intervals, is not different from cumulative data from the entire Society of Thoracic Surgeons Database, both for all patients and for patients stratified by complexity.
A regional consortium of congenital heart surgery centres in Florida under the framework of the Children’s Medical Services has allowed for inter-institutional collaboration with the goal of quality improvement. This experience demonstrates, first, that the database maintained by the Society of Thoracic Surgeons can provide the framework for regional analysis of outcomes, and second, that voluntary regional collaborative efforts permit the pooling of data for such analysis.
Results are presented on the production of oxygen atoms in flowing microwave post-discharges in a reactor of 5 litres at high pressures (10-50 torr). Diagnostics of O-atom densities are obtained by NO titration in the post-discharge. An hydrodynamic and kinetic model has been developed to obtain the spatial distribution of O-atoms inside the post-discharge reactor. Such post-discharge processes at high pressures are of interest for elastomer treatments.
The study of naturally-occurring radiation and its associated risk is one of the
preoccupations of bodies responsible for radiation protection. Cosmic particle flux
is significantly higher on board aircraft that at ground level. Furthermore, its
intensity depends on solar activity and eruptions. Due to their professional activity,
flight crews and frequent flyers may receive an annual dose of some millisieverts.
This is why the European directive adopted in 1996 requires the aircraft operators
to assess the dose and to inform their flight crews about the risk. The effective dose
is to be estimated using various experimental and calculation means. In France, the
computerized system for flight assessment of exposure to cosmic radiation in air
transport (SIEVERT) is delivered to airlines for assisting them in the application of
the European directive. This dose assessment tool was developed by the French
General Directorate of Civil Aviation (DGAC) and partners: the Institute for
Radiation Protection and Nuclear Safety (IRSN), the Paris Observatory and the
French Institute for Polar Research - Paul-Emile Victor (IPEV). This professional
service is available on an Internet server accessible to companies with a public
section. The system provides doses that consider the routes flown by aircraft.
Various results obtained are presented.
Spatio–temporal changes in density, breeding cycle, growth and population structure of Hydrobia ulvae (Gastropoda: Prosobranchia) were studied by monthly sampling of a wide bare mudflat in Marennes-Oléron Bay. Four stations, located along a cross-shore transect and characterized by different geomorphological structures, were investigated from March 2000 to February 2001. Hydrobia ulvae was mainly distributed in the upper half part of the mudflat and no individuals were found in the lower part. The breeding cycle extended from March to December and showed two annual peaks, in spring and in autumn. Three cohorts were recruited during the year and showed high growth rates during summer; the parameters of the von Bertalanffy model describing the growth curves were equal to kmax=0·47±0·5 mm
month−1 and L∞=5·4±0·2 mm. The snail population had similar size–frequency structure along the transect at the beginning of the survey but summer recruitment initiated spatial differentiation. Reproduction occurred in the middle part of the mudflat but recruits mainly settled down at the upper level of the mudflat; new cohorts appeared with increasing individual densities. The middle part of the mudflat was rather dominated by adult individuals which showed large density fluctuations.