Laparoscopic artificial insemination in dairy sheep with chilled semen stored for up to 26 h

Adult East Freisan crossbred (n = 220) and Chios ewes (n = 105) were divided into four groups and inseminated with chilled semen, which had been stored for 7, 13, 20 or 26 h at 5°C. Unilateral intrauterine insemination (50 x 106 spermatozoa in 0.25 ml) was performed with the aid of a laparoscope. Inseminations were carried out 48 – 52 h after pessary removal (30 mg FGA) without detecting estrus. The lambing rates after intrauterine insemination with chilled semen were found to be similar in East Fresian crossbred (40%) and Chios ewes (30%). Intrauterine insemination with chilled semen stored up to 26 h resulted in similar lambing rates; whereas, fertility of Chios ewes tended to decline with increased holding time of chilled semen. From this study, it is concluded that decreasing the storage time of chilled semen at 5°C improves pregnancy in Chios ewes and that East Fresian crossbred ewe’s conception rates to intrauterine insemination with chilled semen was relatively higher than Chios ewes.Key words: Dairy sheep, chilled semen, time of insemination, lambing rate

New evidence about the subduction of the Copiap\uf2 ridge beneath South America, and its connection with the Chilean-Pampean flat slab, tracked by satellite GOCE and EGM2008 models

Satellite-only gravity measurements and those integrated with terrestrial observations provide global gravity field models of unprecedented precision and spatial resolution, which allow analyzing lithospheric structure allowing the analysis of the lithospheric structure. We used the model EGM2008 (Earth Gravitational Model) to calculate the gravity anomaly and the vertical gravity gradient in the South Central Andes region, correcting these quantities by the topographic effect. Both quantities show a spatial relationship between the projected subduction of the Copiap\uf3 aseismic ridge (located at 33 about 27\uba 30\u2019 S), its potential deformational effects in the overriding plate, and the Ojos del Salado-San Buenaventura volcanic lineament. This volcanic lineament constitutes a projection of the volcanic arc towards the retroarc zone, whose origin and development were not clearly understood. The analysis of the gravity anomalies, at the extrapolated zone of the Copiap\uf3 ridge beneath the continent, shows a change in the general NNE38 trend of the Andean structures to an ENE-direction coincident with the area of the Ojos del Salado-San Buenaventura volcanic lineament. This anomalous pattern over the upper plate is interpreted to be linked with the subduction of the Copiap\uf3 ridge. We explore the relation between deformational effects and volcanism at the northern Chilean-Pampean flat slab and the collision of the Copiap\uf3 ridge, on the basis of the Moho geometry and elastic thicknesses calculated from the new satellite GOCE data. Neotectonic deformations interpreted in previous works associated with volcanic eruptions along the Ojos del Salado-San Buenaventura volcanic lineament is interpreted as caused by crustal doming, imprinted by the subduction of the Copiap\uf3 ridge, evidenced by crustal thickening at the sites of ridge inception along the trench. Finally, we propose that the Copiap\uf3 ridge could have controlled the northern edge of the Chilean-Pampean flat slab, due to higher buoyancy, similarly to the control that the Juan Fernandez ridge exerts in the geometry of the flat slab further south

B-physics computations from Nf=2 tmQCD

We present an accurate lattice QCD computation of the b-quark mass, the B and Bs decay constants, the B-mixing bag-parameters for the full four-fermion operator basis, as well as estimates for \xi and f_{Bq}\sqrt{B_q} extrapolated to the continuum limit and the physical pion mass. We have used Nf = 2 dynamical quark gauge configurations at four values of the lattice spacing generated by ETMC. Extrapolation in the heavy quark mass from the charm to the bottom quark region has been carried out using ratios of physical quantities computed at nearby quark masses, having an exactly known infinite mass limit.Comment: 7 pages, 4 figures, presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, German

Development of Wireless Techniques in Data and Power Transmission - Application for Particle Physics Detectors

Wireless techniques have developed extremely fast over the last decade and using them for data and power transmission in particle physics detectors is not science- fiction any more. During the last years several research groups have independently thought of making it a reality. Wireless techniques became a mature field for research and new developments might have impact on future particle physics experiments. The Instrumentation Frontier was set up as a part of the SnowMass 2013 Community Summer Study [1] to examine the instrumentation R&D for the particle physics research over the coming decades: {\guillemotleft} To succeed we need to make technical and scientific innovation a priority in the field {\guillemotright}. Wireless data transmission was identified as one of the innovations that could revolutionize the transmission of data out of the detector. Power delivery was another challenge mentioned in the same report. We propose a collaboration to identify the specific needs of different projects that might benefit from wireless techniques. The objective is to provide a common platform for research and development in order to optimize effectiveness and cost, with the aim of designing and testing wireless demonstrators for large instrumentation systems

Edulingualism: linguistic repertoires, academic tasks and student agency in an English-dominant university

This article reports on a study that examined how a group of plurilingual students use their linguistic repertoires to achieve a number of purposes such as performing identity, learning and socialising, and negotiating with structure in an English-dominant university. In order to capture the dynamic relationship between language-as-resource, academic tasks and agency in this particular context, the article proposes ‘edulingualism’ as a conceptual and analytic lens. To this end, the article examines multiple data sets (narratives, reflective accounts, recorded interactions and texts) that show how, by mobilising their multilingual resources, these students achieve their purposes and take ownership of their learning experiences within a monolingual learning space

Precision scans of the pixel cell response of double sided 3D pixel detectors to pion and x-ray beams

hree-dimensional (3D) silicon sensors offer potential advantages over standard planar sensors for radiation hardness in future high energy physics experiments and reduced charge-sharing for X-ray applications, but may introduce inefficiencies due to the columnar electrodes. These inefficiencies are probed by studying variations in response across a unit pixel cell in a 55μm pitch double-sided 3D pixel sensor bump bonded to TimePix and Medipix2 readout ASICs. Two complementary characterisation techniques are discussed: the first uses a custom built telescope and a 120GeV pion beam from the Super Proton Synchrotron (SPS) at CERN; the second employs a novel technique to illuminate the sensor with a micro-focused synchrotron X-ray beam at the Diamond Light Source, UK. For a pion beam incident perpendicular to the sensor plane an overall pixel efficiency of 93.0±0.5% is measured. After a 10o rotation of the device the effect of the columnar region becomes negligible and the overall efficiency rises to 99.8±0.5%. The double-sided 3D sensor shows significantly reduced charge sharing to neighbouring pixels compared to the planar device. The charge sharing results obtained from the X-ray beam study of the 3D sensor are shown to agree with a simple simulation in which charge diffusion is neglected. The devices tested are found to be compatible with having a region in which no charge is collected centred on the electrode columns and of radius 7.6±0.6μm. Charge collection above and below the columnar electrodes in the double-sided 3D sensor is observed

Frequency of Debris Disks around Solar-Type Stars: First Results from a Spitzer/MIPS Survey

We have searched for infrared excesses around a well defined sample of 69 FGK main-sequence field stars. These stars were selected without regard to their age, metallicity, or any previous detection of IR excess; they have a median age of ~4 Gyr. We have detected 70 um excesses around 7 stars at the 3-sigma confidence level. This extra emission is produced by cool material (< 100 K) located beyond 10 AU, well outside the ``habitable zones'' of these systems and consistent with the presence of Kuiper Belt analogs with ~100 times more emitting surface area than in our own planetary system. Only one star, HD 69830, shows excess emission at 24 um, corresponding to dust with temperatures > 300 K located inside of 1 AU. While debris disks with Ld/L* > 10^-3 are rare around old FGK stars, we find that the disk frequency increases from 2+-2% for Ld/L* > 10^-4 to 12+-5% for Ld/L* > 10^-5. This trend in the disk luminosity distribution is consistent with the estimated dust in our solar system being within an order of magnitude, greater or less, than the typical level around similar nearby stars.Comment: 11 figure