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Late Pleistocene glacial terminations are caused by rising atmospheric CO2occurring in response to atmospheric and ocean circulation changes induced by increased discharge from Northern Hemisphere ice sheets. While climate records place glacial terminations coincident with decreasing orbital precession, it remains unclear why a specific precession minimum causes a termination. We compare the orbital and ice volume configuration at each precession minima over the last million years to demonstrate that eccentricity, through its control on precession amplitude, period and coherence with obliquity, along with ice sheet size, determine whether a given precession minimum will cause a termination. We also demonstrate how eccentricity controls obliquity maxima and precession minima coherence, varying the duration of glaciations. Glaciations lasting ∼100 thousand years are controlled by Earth's eccentricity cycle of the same period, while the shortest (20–40 ka) and longest (155 ka) occupy the maxima and minimums of the 400 thousand year eccentricity cycle. The Milankovitch theory of the ice ages predicts that the growth and collapse of Pleistocene ice sheets is paced by the cycles in high latitude solar insolation that accompany variations in Earth's orbital motion. The orbital modes that dominate frequencies of incoming solar radiation are obliquity and precession, which operate at periodicities of approximately 40 and 20 thousand years, respectively. The dominant frequency at which ice sheets grow and collapse over the last million years is, however, approximately 100 thousand years, a closer match to eccentricity, an orbital period near absent from past solar radiation. Through a comparison between Earth's orbital configuration and an approximation of past global ice volume, we identify that the precession minima that trigger ice sheet collapse occur at distinct configuration of eccentricity and ice sheet size. In most cases terminations occur when precession minima align with obliquity maxima. We find that this coherence is influenced by the duration of precession cycles, which is in turn controlled by eccentricity. From these observations, we conclude that orbital eccentricity, through its control on both the amplitude and period of precession, paces the timing of glacial terminations and the size of Late Pleistocene ice sheets. Late Pleistocene glacial terminations occur at distinct configurations of orbital precession, obliquity, eccentricity and ice volumeEccentricity controls the duration of precession cycles, and therefore the coherence of obliquity and precessionOrbital eccentricity, through its control on the amplitude and period of precession, paces Late Pleistocene glaciations Late Pleistocene glacial terminations occur at distinct configurations of orbital precession, obliquity, eccentricity and ice volume Eccentricity controls the duration of precession cycles, and therefore the coherence of obliquity and precession Orbital eccentricity, through its control on the amplitude and period of precession, paces Late Pleistocene glaciations

Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth’s past interglacial warm periods1–3. About 400,000 years ago, during the interglacial period known as Marine Isotopic Stage 11 (MIS11), the global temperature was 1 to 2 degrees Celsius greater2and sea level was 6 to 13 metres higher1,3. Sea level estimates in excess of about 10 metres, however, have been discounted because these require a contribution from the East Antarctic Ice Sheet3, which has been argued to have remained stable for millions of years before and includes MIS114,5. Here we show how the evolution of 234U enrichment within the subglacial waters of East Antarctica recorded the ice sheet’s response to MIS11 warming. Within the Wilkes Basin, subglacial chemical precipitates of opal and calcite record accumulation of 234U (the product of rock–water contact within an isolated subglacial reservoir) up to 20 times higher than that found in marine waters. The timescales of 234U enrichment place the inception of this reservoir at MIS11. Informed by the 234U cycling observed in the Laurentide Ice Sheet, where 234U accumulated during periods of ice stability6and was flushed to global oceans in response to deglaciation7, we interpret our East Antarctic dataset to represent ice loss within the Wilkes Basin at MIS11. The 234U accumulation within the Wilkes Basin is also observed in the McMurdo Dry Valleys brines8–10, indicating11that the brine originated beneath the adjacent East Antarctic Ice Sheet. The marine origin of brine salts10and bacteria12implies that MIS11 ice loss was coupled with marine flooding. Collectively, these data indicate that during one of the warmest Pleistocene interglacials, the ice sheet margin at the Wilkes Basin retreated to near the precipitate location, about 700 kilometres inland from the current position of the ice margin, which—assuming current ice volumes—would have contributed about 3 to 4 metres13to global sea levels.

AbstractPiccione, G., Casella, S., Giannetto, C., Monteverde, V. and Ferrantelli, V. 2009. Exercise-induced modifications on haematochemical and electrophoretic parameters during 1600 and 2000 meters trot races in Standardbred horses. J. Appl. Anim. Res., 35: 131–135.The aim of the present study was to evaluate the modifications of some haematochemical and electrophoretic parameters during two different workloads in Standardbred horses. Ten clinically healthy horses were divided into two equal groups, taking part in an official trot race at 1600 or 2000 meters course, respectively. Blood samples were collected from each horse at rest, after warm up, 0, 30 and 60 min after the end of the race. Serum concentrations of albumin, globulins, total proteins, total cholesterol, triglycerides, glucose, hydroxybutyrate, urea, creatinine, creatine kinase (CK), glutamate pyruvate transaminases (GPT) and glutamate oxalacetate transaminases (GOT) were assessed. Exercise increased triglyceride, glucose, creatinine and CK and decreased GOT which tended to reach rest level 60 min after exercise. Globulins were affected by exercise but there was no set pattern.

AbstractPiccione, G., Borruso, M., Fazio, F., Grasso, F. and Caola, G. 2006. Oxidative stress evaluation during milking period in the ewes. J. Appl. Anim. Res., 29: 109–112.The role of oxygen free radicals is considered important especially during productive phases in domestic animals. To investigate the effects of the antioxidant mechanisms during different phases of milking and during dry period 5 Valle del Belice ewes were used. Blood samples were taken on days 1, 40 and 200 of milking and during dry period. Serum samples were assessed for antioxidant barrier (Oxy-adsorbent), reactive oxygen species (dROMs) and thiol antioxidant barrier (SHp). Oxidative processes increased (P<0.05) at the end of milking period, together with a compensative response of the organism to this stress and suggest the important role of oxidative status in dairy ewes.

Definition of the temporal characteristics of cardiovascular rhythms is of scientific interest. This article reviews the literature on the rhythmic pattern of some cardiovascular parameters in domestic animals, providing greater understanding of general chronobiological processes in mammals. The techniques of the chronophysiological studies have been applied in domestic species to determine the existence of periodicity in the cardiovascular functions. Detailed knowledge of these rhythms is useful for clinical, practical and pharmacological purposes and physical performances.