Real-time ultrasonography for pregnancy diagnosis and foetal ageing in fallow deer

SUMMARY Three groups of 15 to 17 adult fallow does with some additional yearling does in 2 of the groups were treated to synchronise oestrous cycles, and mated. All does were scanned by ultrasound at 4 weeks of gestation and at weekly intervals from week 7 to week 14 of gestation. Growth rates of 13 foetal and uterine characters, which have been used for ageing foetuses of red deer, were similar for adult and yearling does and among the 3 groups. Transrectal ultrasound scanning was a reliable and accurate means of detecting pregnancy and of ageing foetuses of fallow deer during weeks 7 to 17 of pregnancy.     

The effect of autonomic manipulation on heart rate variability in dogs

Beat‐to‐beat variation of heart rate is reflective of autonomic balance and has been used to assess pain and stress in human beings. The purpose of this investigation was to pharmacologically manipulate the autonomic nervous system and to determine the effect of these manipulations on heart rate variability (HRV) in dogs. Four adult male hound dogs (27 ± 1 kg) were used in the investigation. Each dog was given five treatments: Parasympathetic blockade (glycopyrrolate; 0.01 mg kg^–1 IV and 0.01 mg kg^–1 IM), parasympathetic stimulation (phenylephrine; 0.005 mg kg^–1 IV + 0.05 mg kg^–1hour^–1), sympathetic blockade (propranolol; 0.11 mg kg^–1 IV), sympathetic stimulation propranolol; 0.01 μg kg^–1 minute^–1), and saline control. At least 48 hours were allowed between treatments. ECG recordings were obtained using an ambulatory ECG monitor. A 5‐minutes period of continuous recording obtained ~30 minutes after initiation of drug administration was used for data analysis. Changes in HRV were evaluated by time and frequency‐domain analysis. The standard deviation of normal R‐R intervals (SDNN), as well as the standard deviation of successive differences in RR intervals (SDSD) were assessed for each treatment. Low frequency (LFP; 0.05–0.15 Hz), high frequency (HFP; 0.15–0.35 Hz), and total (TP; 0.017–0.5 Hz) spectral power were also determined. The LFP:HFP ratio was also evaluated. A two‐way anova with a Tukey's test was used to detect differences (p < 0.05). Administration of glycopyrrolate or isoproterenol increased HR and decreased SDNN and SDSD below control levels. Phenylephrine or propranolol administration were without effect. LFP was diminished by glycopyrrolate and isoproterenol, but was unaffected by phenylephrine and propranolol. HFP, TP, and LFP:HFP were unaffected by treatment. Both branches of the autonomic nervous system influence SDNN and LFP. SDSD, in contrast, is altered primarily by parasympathetic activity. Thus, it appears that parasympathetic activity modulates HRV in the resting dog, as either withdrawal of parasympathetic influence or accentuated sympathetic activity led to significant changes in these measures of HRV. Conversely, augmentation of parasympathetic activity or withdrawal of sympathetic tone minimally affected HRV.     

A tool for identifying potential Eucalyptus nitens seed orchard sites based on climate and topography

Shy seed production in orchards of Eucalyptus nitens is a major barrier to the deployment of genetic gain in South African plantations. A machine learning method was used to identify optimal sites for the establishment of E. nitens seed orchards within the plantation forestry landscape of the summer rainfall region of South Africa. The ensemble classifier random forests (RF) was used to identify the environmental factors conducive to E. nitens floral bud production, and, based on these, build a predictive model deployable to the plantation forestry landscape for identifying suitable areas for E. nitens seed orchards. The RF model predicted site suitability likelihood for floral bud production with a high level of accuracy (area under the receiver operating characteristic curve = 0.83). Within the climatically optimal range for growing E. nitens, flower bud production was more abundant and consistent on cold slopes, i.e. sites experiencing lower minimum air temperatures during spring and autumn. The model was applied to the commercial plantation forestry landscape for the purpose of indicating sites climatically optimal for floral bud production in E. nitens and the establishment of breeding and seed production orchards of the same species.     

Colossal Magnetoresistance Without Mn3+/Mn4+ Double Exchange in the Stoichiometric Pyrochlore Tl2Mn2O7

Structural analysis from powder neutron and single-crystal x-ray diffraction data for a sample of the Tl2Mn2O7 pyrochlore, which exhibits colossal magnetoresistance (CMR), shows no deviations from ideal stoichiometry. This analysis gives an Mn-O distance of 1.90 angstroms, which is significantly shorter than the Mn-O distances (1.94 to 2.00 angstroms) observed in phases based on LaMnO3 perovskites that exhibit CMR. Both results in Tl2Mn2O7 indicate oxidation states very close to Tl23+Mn24+O7. Thus, Tl2Mn2O7 has neither mixed valence for a double-exchange magnetic interaction nor a Jahn-Teller cation such as Mn3+, both of which were thought to have an important function in CMR materials. An alternate mechanism for CMR in Tl2Mn2O7 based on magnetic ordering driven by superexchange and strong spin-fluctuation scattering above the Curie temperature is proposed here.     

EFFECT OF COPPER SMELTING AIR POLLUTION ON THE MITES (ACARI) ASSOCIATED WITH YOUNG SCOTS PINE FORESTS POLLUTED BY A COPPER SMELTING WORKS AT GŁOGÓW,POLAND. II. SOIL MITES

Water, Air, &; Soil Pollution - The soil mites were investigated in the areas covered with dead needles in young Scots pine forests (plant association Leucobryo-Pinetum), polluted by a copper...     

International Cooperation in Space: A wide variety of joint projects contribute to science and have practical applications

NASA has developed an extensive program of international cooperation, which opens the entire range of its space activities to foreign participation and benefit. The program has involved developing as well as advanced countries in activities that are fruitful scientifically, technically, economically, and (it may be hoped) politically. "Gaps" or limitations in the program are found in the areas of manned space flight and large booster development and in cooperation with the Soviet Union. In the first case, the low level of European budgeting is the prime explanation, perhaps reflecting Europe's late start in the space business and an early underestimate of its values and possibilities. In the second case, the explanation seems to rest with Soviet political views rather than with technical problems or any lack of interest by the United States. Openhanded efforts are currently under way to raise the level of foreign participation in the space programs of the next decade, but it is too early to estimate their chances of major success. Public commentary could undoubtedly assist these efforts more effectively if it were directed more clearly to the actual sources of restriction on foreign participation. Despite the restricting factors abroad, however, there is every reason to persevere with existing and improved programs for international cooperation.     

Past temperatures directly from the greenland ice sheet

A Monte Carlo inverse method has been used on the temperature profiles measured down through the Greenland Ice Core Project (GRIP) borehole, at the summit of the Greenland Ice Sheet, and the Dye 3 borehole 865 kilometers farther south. The result is a 50, 000-year-long temperature history at GRIP and a 7000-year history at Dye 3. The Last Glacial Maximum, the Climatic Optimum, the Medieval Warmth, the Little Ice Age, and a warm period at 1930 A.D. are resolved from the GRIP reconstruction with the amplitudes -23 kelvin, +2.5 kelvin, +1 kelvin, -1 kelvin, and +0.5 kelvin, respectively. The Dye 3 temperature is similar to the GRIP history but has an amplitude 1.5 times larger, indicating higher climatic variability there. The calculated terrestrial heat flow density from the GRIP inversion is 51.3 milliwatts per square meter.     

Indigofera spicata (creeping indigo) poisoning of three ponies

Three ponies continuously grazed a pasture containing an estimated 24% Indigofera spicata (wet weight basis) for 4–6 weeks in April and May 2004. They developed ataxia, paresis, depression, muscle fasciculations, dysphagia, ptyalism and halitosis. Two also developed corneal opacity. One pony recovered with supportive treatment, but the other two were euthanased and necropsied. Neuropathology was not present in either case, but both livers had periacinar and periportal lymphocytic infiltrations and hydropic degeneration of mid‐zonal hepatocytes, with mild to moderate periacinar necrosis also evident in one. The I. spicata contained 2.66 mg 3‐nitropropionic acid (3‐NPA)/g dry matter and 1.5 mg indospicine/g dry matter. Indospicine, but not 3‐NPA, was detected in serum from both of the euthanased ponies and indospicine was detected in heart, liver and muscle from the one pony in which this assay was performed. The clinical syndrome closely resembled ‘Birdsville horse disease’ caused by I. linnaei and was similar to that reported in horses poisoned by the closely related species I. hendecaphylla and to 3‐NPA poisoning of other animals, including humans. 3‐NPA is thought to cause this neurological syndrome. To our knowledge, this is the first authenticated report of I. spicata poisoning in grazing animals. We also report here the first published evidence that 3‐NPA and indospicine exist in naturalised I. spicata in Australia and of the formation of indospicine residues in tissues of animals grazing paddocks infested with I. spicata.