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The last couple of years have been an eventful time for trade policy and in particular for major preferential trade agreements (PTAs), such as the so-called mega-regionals. Early 2016, twelve Pacific Rim countries, including Canada and the United States (USA), signed the Trans-Pacific Partnership (TPP) agreement. Around the same time, Canada and the European Union (EU) agreed at the level of negotiators to conclude the Comprehensive Economic and Trade Agreement (CETA). Finally, the USA and the EU continued their efforts to find common ground in the negotiations towards the proposed Transatlantic Trade and Investment Partnership (TTIP) treaty.
The hairpin instability of a jet in a crossflow (JICF) for a low jet-to-crossflow velocity ratio is investigated experimentally for a velocity ratio range of
and crossflow Reynolds numbers
. From spectral analysis we characterize the Strouhal number and amplitude of the hairpin instability as a function of
. We demonstrate that the dynamics of the hairpins is well described by the Landau model, and, hence, that the instability occurs through Hopf bifurcation, similarly to other hydrodynamical oscillators such as wake behind different bluff bodies. Using the Landau model, we determine the precise threshold values of hairpin shedding. We also study the spatial dependence of this hydrodynamical instability, which shows a global behaviour.
Austria has a quite small cooperative sector, only about 10 to 15% of all Austrian wine is produced by wine cooperatives. The first wine cooperative was established in 1882 (Eisenstadt-Ruster-Weinproduzentenverein). An intense wave of cooperative establishment took place in Austria and Germany at the beginning of the 20th century, lasting through the 1960s, that was due to the unfortunate general socio-economic situation of vintners.
Recent advances in high-angular resolution instruments (VLT and VLTI, ALMA) have enabled us to delve deep into the circumstellar envelopes of AGB stars from the optical to the sub-mm wavelengths, thus allowing us to study in detail the gas and dust formation zones (e.g., their geometry, chemistry and kinematics). This work focuses on four (4) C-rich AGB stars observed with a high-angular resolution technique in the near-infrared: a multi-wavelength tomographic study of the dusty layers of the circumstellar envelopes of these C-rich stars, i.e. the variations in the morphology and temperature distribution.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
We present detailed experiments on transient growth of turbulent spots induced by external forcing in plane Couette–Poiseuille flow, which are studied in the framework of linear transient growth. The experimental investigation is supplemented with full theoretical analysis. We compare quantitatively the experimental and theoretical results, including maximal gain and the time at which it occurs. We also present the limits of validity for the application of the linear theory at high amplitude perturbation and Reynolds number, showing experiments with self-sustained states.
The Zadko telescope is a 1 m f/4 Cassegrain telescope, situated in the state of Western Australia about 80-km north of Perth. The facility plays a niche role in Australian astronomy, as it is the only meter class facility in Australia dedicated to automated follow-up imaging of alerts or triggers received from different external instruments/detectors spanning the entire electromagnetic spectrum. Furthermore, the location of the facility at a longitude not covered by other meter class facilities provides an important resource for time critical projects. This paper reviews the status of the Zadko facility and science projects since it began robotic operations in March 2010. We report on major upgrades to the infrastructure and equipment (2012–2014) that has resulted in significantly improved robotic operations. Second, we review the core science projects, which include automated rapid follow-up of gamma ray burst (GRB) optical afterglows, imaging of neutrino counterpart candidates from the ANTARES neutrino observatory, photometry of rare (Barbarian) asteroids, supernovae searches in nearby galaxies. Finally, we discuss participation in newly commencing international projects, including the optical follow-up of gravitational wave (GW) candidates from the United States and European GW observatory network and present first tests for very low latency follow-up of fast radio bursts. In the context of these projects, we outline plans for a future upgrade that will optimise the facility for alert triggered imaging from the radio, optical, high-energy, neutrino, and GW bands.
Anthrax is a disease caused by the gram-positive, aerobic bacterium Bacillus anthracis and was recognized in antiquity. The disease figures prominently in the history of modern medicine because it was the first bacterial illness for which successful vaccines were prepared, almost simultaneously by William Smith Greenfield in London and Louis Pasteur in Paris. Anthrax is a zoonosis of herbivores which is encountered worldwide and human cases continue to be seen not infrequently in Turkey, Iran, Afghanistan, Thailand, and countries of sub-Saharan Africa. Grazing wild animals and cattle are very susceptible and human disease in animal husbandmen and herders is closely tied to exposure to infected beasts. Propagating the bacteria in the spore form is used in bioterrorism, a novel and more recent form of human exposure to anthrax, utilizing delivery systems such as the postal service.
To understand anthrax one must keep in mind the natural cycle of disease in animals: spores survive prolonged periods in alkaline soils, rainwater concentrates spores in low-lying depressions and susceptible herbivores gather in these locales during dry periods and inhale aerosolized spores or swallow spores loosely attached to forage. These geographic and climatic factors are usually present prior to animal outbreaks and may culminate in humans being infected accidentally. Spores arise from bacilli exposed to ambient air when blood from dying animals reaches the soil or carcasses are torn apart by scavengers. When the bacilli are exposed to air, spores form in the central and subterminal part of the bacillus. Spores may survive for prolonged periods (~90 years) in soil rich with organic material, a pH greater than 6.1 (alkaline soils) with high concentrations of Ca++. This characterizes a wide geographic swathe in the middle United States from Texas to North Dakota. It is also true for soils in the steppes of Asia and in sub-Saharan Africa where anthrax remains common in wildlife. Although anthrax is considered an obligate pathogen, it is likely that in some circumstances a vegetative bacillus-spore cycle occurs independent of infection in the soil alone.
The objective was to investigate the effect of intake before fasting on concentrations of metabolites and hormones, respiratory quotient (RQ) and fasting heat production (HP) using the washed rumen technique and to compare these values with those from the fed state. Six Holstein steers (360±22 kg) were maintained at 21°C and fed three different energy intakes within a replicated 3×3 Latin square design with 21-day periods. Steers were fed alfalfa cubes to provide 1.0, 1.5 and 2.0×NEm during 19 days of each experimental period. Steers were placed in individual metabolism stalls fitted with indirect calorimetry head-boxes on day 20 of each experimental period (FED steers) and fed their normal meal. On day 21 of each period the reticulorumen was emptied, washed and refilled with ruminal buffer (NaCl=96; NaHCO3=24; KHCO3=30; K2HPO4=2; CaCl2=1.5; MgCl2=1.5 mmol/kg of buffer) aerated with 75% N2 and 25% CO2 before introduction to the rumen (steers were not fed; WASHED steers). Each gas exchange was measured over 24 h. HP for 1.0, 1.5 and 2.0×NEm were 479, 597 and 714 kJ/daykg0.75 (s.e.m. =16), respectively. The plateau RQ was 0.756, 0.824 and 0.860 for the 1.0, 1.5 and 2.0×NEm intakes for the FED steers, respectively. After rumen washing, fasting HP was 331, 359 and 400 kJ/daykg0.75 (s.e.m.=13) for 1.0, 1.5, and 2.0×NEm intakes before fasting, respectively. The RQ for WASHED rumen steers was 0.717, 0.710 and 0.719, respectively. Cortisol and β-hydroxybutyrate concentrations in WASHED rumen steers did not exceed threshold levels for severe energy deficit and stress as can be induced from prolonged fasting. This study demonstrates that a fasting state can be emulated using the washed rumen technique, minimizing the time required as opposed to traditional fasting methodologies, without causing a severe energy deficit and stress.
Ergot alkaloids in endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum) have been shown to cause a reduction in blood flow to the rumen epithelium as well as a decrease in volatile fatty acids (VFA) absorption from the washed rumen of steers. Previous data also indicates that incubating an extract of endophyte-infected tall fescue seed causes an increase in the amount of VFA absorbed per unit of blood flow, which could result from an alteration in the absorptive or barrier function of the rumen epithelium. An experiment was conducted to determine the acute effects of an endophyte-infected tall fescue seed extract (EXT) on total, passive or facilitated acetate and butyrate flux across the isolated bovine rumen as well as the barrier function measured by inulin flux and tissue conductance (Gt). Flux of ergovaline across the rumen epithelium was also evaluated. Rumen tissue from the caudal dorsal sac of Holstein steers (n=6), fed a common diet, was collected and isolated shortly after slaughter and mounted between two halves of Ussing chambers. In vitro treatments included vehicle control (80% methanol, 0.5% of total volume), Low EXT (50 ng ergovaline/ml) and High EXT (250 ng ergovaline/ml). Results indicate that there is no effect of acute exposure to ergot alkaloids on total, passive or facilitated flux of acetate or butyrate across the isolate bovine rumen epithelium (P>0.51). Inulin flux (P=0.16) and Gt (P>0.17) were not affected by EXT treatment, indicating no alteration in barrier function due to acute ergot alkaloid exposure. Ergovaline was detected in the serosal buffer of the High EXT treatment indicating that the flux rate is ~0.25 to 0.44 ng/cm2 per hour. Data indicate that specific pathways for VFA absorption and barrier function of the rumen epithelium are not affected by acute exposure to ergot alkaloids from tall fescue at the concentrations tested. Ergovaline has the potential to be absorbed from the rumen of cattle that could contribute to reduced blood flow and motility and lead to reduced growth rates of cattle.
The wake behind a cube with a face normal to the flow was investigated experimentally in a water tunnel using laser induced fluorescence (LIF) visualisation and particle image velocimetry (PIV) techniques. Measurements were carried out for moderate Reynolds numbers between 100 and 400 and in this range a sequence of two flow bifurcations was confirmed. Values for both onsets were determined in the framework of Landau’s instability model. The measured longitudinal vorticity was separated into three components corresponding to each of the identified regimes. It was shown that the vorticity associated with a basic flow regime originates from corners of the bluff body, in contrast to the two other contributions which are related to instability effects. The present experimental results are compared with numerical simulation carried out earlier by Saha (Phys. Fluids, vol. 16, 2004, pp. 1630–1646).
The history of music in the Indian subcontinent is extremely long, and the territory of India so vast, that any representation of it must be understood as the result of draconian choices. Historians and other writers on India have ruminated about the possible nexus between Indian music and the music of other ancient civilizations. One significant example of global encounter that resulted from the dissemination of Buddhism resides in a musical instrument: the ovoid-shaped lute that we know as the oud/pipa/biwa, which originated at the far western end of the Silk Road. Music theory, as developed by Indo-Aryans within a Brahmanic intellectual tradition, became the theory of ancient India, so widespread that it is assumed that musicians and theorists throughout the subcontinent shared one system. In South India, music continued to flourish under the patronage of the Maratha kings in late seventeenth- and eighteenth-century Thanjavur, the principal seat of Karnatak music before Madras gained that reputation.