Follicular wave synchronization using buserelin in llama (Lama glama)

The objective of the study was to synchronize follicular wave emergency using busereline in a group of llamas that were at different stages of their follicular waves. We used 16 non-pregnant, nonlactating females divided according to their follicular dynamics determined ultrasonographically three days previously, into 4 groups: I: follicles smaller than 6 mm; II: growing follicles from 7 to 10 mm; III: maturing follicles from 8 to 14 mm and IV: regressing follicles, decreasing over two consecutive days. The animals received 8 µg of busereline (day 0) and ovarian activity was followed using ultrasound scanning until a dominant follicle (? 7 mm) was detected. The smallest mean maximum follicular diameter was observed on day 3, there being no significant differences between the 4 groups (P=0.50). The time interval from the GnRH injection to the detection of a follicle ? 7 mm was 6.25 ± 1.29 days in group I; 5.5 ± 1.8 days in group II; 5.5 ± 1.1 days in group III and 8.66 ± 1.88 days in group IV. The moment of the detection of a dominant follicle was not statistically different (P=0.26). In conclusion, the use of busereline in llamas that are in different follicular phases synchronizes the emergence of the follicular wave and permits starting superstimulatory treatments between days 3 and 6 after its injection.Fil: Ferrer, M.S. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Área de Teriogenología. Buenos Aires, ArgentinaFil: Agüero, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Área de Teriogenología. Buenos Aires, ArgentinaFil: Chaves, M.G. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Área de Teriogenología. Buenos Aires, ArgentinaFil: Russo, A.F. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Área de Teriogenología. Buenos Aires, ArgentinaFil: Rutter, B. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Área de Teriogenología. Buenos Aires, ArgentinaEl objetivo del estudio fue sincronizar la emergencia de la onda folicular mediante la aplicación de buserelina, en animales que se encontraban en diferentes fases de su dinámica folicular. Se utilizaron 16 hembras vacías no en lactancia divididas en 4 grupos en base a su dinámica folicular determinada ultrasonográficamente durante los 3 días previos: I: folículos menores a 6 mm; II: folículos en crecimiento entre 7 y 10 mm; III: folículos en fase estática entre 8 y 14 mm y IV: folículos en regresión luego de dos mediciones consecutivas en descenso. Los animales recibieron 8 µg de buserelina (día 0) y se realizó el seguimiento de la actividad ovárica mediante ultrasonografía hasta detectar la presencia de un folículo dominante (mayor o igual a 7 mm). El menor diámetro folicular máximo promedio en los 4 grupos se observó el día 3 no existiendo diferencias significativas entre los grupos (P= 0,50). El tiempo transcurrido desde la aplicación del análogo de GnRH hasta la detección de un folículo mayor o igual a 7 mm fue de 6,25 ± 1,29 días para el grupo I; 5,5 ± 1,8 días para el grupo II; 5,5 ± 1,1 días para el grupo III y 8,66 ± 1,88 días para el grupo IV. No hubo diferencias significativas en el momento de la detección del folículo dominante (P=0,26). En conclusión la aplicación de buserelina en llamas que se encuentran en distintas fases de su dinámica folicular, sincroniza la emergencia de la onda folicular y permite comenzar los tratamientos superestimulatorios entre los días 3 y 6 de la aplicación

Contact resistance in graphene-based devices

We report a systematic study of the contact resistance present at the interface between a metal (Ti) and graphene layers of different, known thickness. By comparing devices fabricated on 11 graphene flakes we demonstrate that the contact resistance is quantitatively the same for single-, bi-, and tri-layer graphene ($\sim800 \pm 200 \Omega \mu m$), and is in all cases independent of gate voltage and temperature. We argue that the observed behavior is due to charge transfer from the metal, causing the Fermi level in the graphene region under the contacts to shift far away from the charge neutrality point

Seed oil content, fatty acids composition and antioxidant properties as affected by genotype in Allium cepa L. and perennial onion species

The antioxidant content in plant seeds is deemed to affect seed oil protection against auto-oxidation to a large extent, whereas the relationship between a strong antioxidant element such as selenium (Se) and either seed oil accumulation or fatty acids composition has not been investigated so far. The aim of the present work was to assess Se concentrations in seeds and their relationships with oil content and fatty acids composition in: a) ten Allium cepa cultivars, i. e. eight Russian and two Italian; and b) six perennial onion species (A. schoenoprasum, A. obliquum, A. altaicum, A. fistulosum, A. nutans, A. ramnósum). Fatty acids composition of Allium seed oil was determined by gas chromatography method, whereas total and water soluble Se concentration was assessed by microfluorimetric method. The oil content of Allium cepa seeds was 1.7 fold higher (10.7-16.5%) than that recorded in perennial onions (4.0-10.8%) and it was positively correlatedwith the total Se concentration. Within A. cepa, the seeds of the two Italian cultivars Ramata di Montoro and Rossa di Tropea were characterized by the highest oil content (16.5-16.6%) and oleic acid (25-27%). Linoleic (C18:2) acid was the main fatty acid, followed by oleic (C18:1) and palmitic acids (C16:0) in all cultivars. Among the perennial onion seeds, the highest oil percentage was detected in A. schoenoprasum (10.8%) and the lowest in A. ramnósum (4.0%). Compared to A.cepa cultivars, the perennial onion species showed a similar oil fatty acid composition, with the main acids being C18:2,C18:1 and C16:0 in decreasing order, a lower level of C16:0, and enhanced levels of minor SFA, such as C20:0, C22:0 and C24:0. Further differences also included decreased levels of C16:1, 11-trance C18:1 and a higher concentration of C22:1. The concentration of water soluble forms of Se in seeds was positively correlated with linoleic acid and with total phenolics. Conversely, oleic acid was negatively correlated with water soluble forms of Se

Resonant charge and spin transport in a t-stub coupled to a superconductor

We study transport through a single channel t-stub geometry strongly coupled to a superconducting reservoir. In contrast to the standard stub geometry which has both transmission resonances and anti-resonances in the coherent limit, we find that due to the proximity effect, this geometry shows neither a T=1 resonance (T is the transmission probability for electrons incident on the t-stub) nor a T=0 anti-resonance as we vary the energy of the incident electron. Instead, we find that there is only one resonant value at T=1/4, where charge transport vanishes while the spin transport is perfect.Comment: This is the published versio

SS Ari: a shallow-contact close binary system

Two CCD epochs of light minimum and a complete R light curve of SS Ari are presented. The light curve obtained in 2007 was analyzed with the 2003 version of the W-D code. It is shown that SS Ari is a shallow contact binary system with a mass ratio $q=3.25$ and a degree of contact factor f=9.4(\pm0.8%). A period investigation based on all available data shows that there may exist two distinct solutions about the assumed third body. One, assuming eccentric orbit of the third body and constant orbital period of the eclipsing pair results in a massive third body with $M_3=1.73M_{\odot}$ and P_3=87.0$yr. On the contrary, assuming continuous period changes of the eclipsing pair the orbital period of tertiary is 37.75yr and its mass is about$0.278M_{\odot}$. Both of the cases suggest the presence of an unseen third component in the system.Comment: 28 pages, 9 figures and 5 table

On the effect of multiple parallel nonlinear absorbers in palliation of torsional response of automotive drivetrain

Torsional vibrations transmitted from the engine to the drivetrain system induce a plethora of noise, vibration and harshness (NVH) concerns, such a transmission gear rattle and clutch in-cycle vibration, to name but a few. The main elements of these oscillations are variations in the inertial imbalance and the constituents of combustion power torque, collectively referred to as engine order vibration. To attenuate the effect of these transmitted vibrations and their oscillatory effects in the drive train system, a host of palliative measures are employed in practice, such as clutch pre-dampers, slipping discs, dual mass flywheel and others, all of which operate effectively over a narrow band of frequencies and have various unintended repercussions. These include increased powertrain inertia, installation package space and cost. This paper presents a numerical study of the use of multiple Nonlinear Energy Sinks (NES) as a means of attenuating the torsional oscillations for an extended frequency range and under transient vehicle manoeuvres. Frequency–Energy Plots (FEP) are used to obtain the nonlinear absorber parameters for multiple NES coupled in parallel to the clutch disc of a typical drivetrain configuration. The results obtained show significant reduction in the oscillations of the transmission input shaft, effective over a broad range of response frequencies. It is also noted that the targeted reduction of the acceleration amplitude of the input shaft requires significantly lower NES inertia, compared with the existing palliative measures

Characterization of Antibodies against Receptor Activity-Modifying Protein 1 (RAMP1): A Cautionary Tale

Calcitonin gene-related peptide (CGRP) is a key component of migraine pathophysiology, yielding effective migraine therapeutics. CGRP receptors contain a core accessory protein subunit: receptor activity-modifying protein 1 (RAMP1). Understanding of RAMP1 expression is incomplete, partly due to the challenges in identifying specific and validated antibody tools. We profiled antibodies for immunodetection of RAMP1 using Western blotting, immunocytochemistry and immunohistochemistry, including using RAMP1 knockout mouse tissue. Most antibodies could detect RAMP1 in Western blotting and immunocytochemistry using transfected cells. Two antibodies (844, ab256575) could detect a RAMP1-like band in Western blots of rodent brain but not RAMP1 knockout mice. However, cross-reactivity with other proteins was evident for all antibodies. This cross-reactivity prevented clear conclusions about RAMP1 anatomical localization, as each antibody detected a distinct pattern of immunoreactivity in rodent brain. We cannot confidently attribute immunoreactivity produced by RAMP1 antibodies (including 844) to the presence of RAMP1 protein in immunohistochemical applications in brain tissue. RAMP1 expression in brain and other tissues therefore needs to be revisited using RAMP1 antibodies that have been comprehensively validated using multiple strategies to establish multiple lines of convincing evidence. As RAMP1 is important for other GPCR/ligand pairings, our results have broader significance beyond the CGRP field

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Evanescent wave transport and shot noise in graphene: ballistic regime and effect of disorder

We have investigated electrical transport and shot noise in graphene field effect devices. In large width over length ratio $W/L$ graphene strips, we have measured shot noise at low frequency ($f$ = 600--850 MHz) in the temperature range of 4.2--30 K. We observe a minimum conductivity of $\frac{4e^{2}}{\pi h}$ and a finite and gate dependent Fano factor reaching the universal value of 1/3 at the Dirac point, i.e. where the density of states vanishes. These findings are in good agreement with the theory describing that transport at the Dirac point should occur via evanescent waves in perfect graphene samples with large $W/L$. Moreover, we show and discuss how disorder and non-parallel leads affect both conductivity and shot noise.Comment: Extended version (19 pages, 10 figures) of Phys. Rev. Lett. 100, 196802 (2008). Additional data on the effect of disorder and non-parallel leads. Submitted for publication in Journal of Low Temperature Physics for the Proceedings of the International Symposium on Quantum Phenomena and Devices at Low Temperatures (ULTI 2008), Espoo, Finlan

Priority questions for biodiversity conservation in the Mediterranean biome: Heterogeneous perspectives across continents and stakeholders

The identification of research questions with high relevance for biodiversity conservation is an important step towards designing more effective policies and management actions, and to better allocate funding among alternative conservation options. However, the identification of priority questions may be influenced by regional differences in biodiversity threats and social contexts, and to variations in the perceptions and interests of different stakeholders. Here we describe the results of a prioritization exercise involving six types of stakeholders from the Mediterranean biome, which includes several biodiversity hotspots spread across five regions of the planet (Europe, Africa, North and South America, and Australia). We found great heterogeneity across regions and stakeholder types in the priority topics identified and disagreement among the priorities of research scientists and other stakeholders. However, governance, climate change, and public participation issues were key topics in most regions. We conclude that the identification of research priorities should be targeted in a way that integrates the spectrum of stakeholder interests, potential funding sources and regional needs, and that further development of interdisciplinary studies is required. The key questions identified here provide a basis to identify priorities for research funding aligned with biodiversity conservation needs in this biome