Isolation of the Toxic Principle of \u3cem\u3eMoraea pallida\u3c/em\u3e by Means of the Sensory Receptors of Sheep

Chemical fractions of Moraea pallida were offered to a sheep in which aversion to the plant had previously been established. Fractions refused due to the presence of the aversive substance sensed by the sheep were further purified until a single substance had been isolated. The purified substance was characterized as epoxyscillirosidin, the toxic principle of M. pallida

Critical Phenomena in Neutron Stars I: Linearly Unstable Nonrotating Models

We consider the evolution in full general relativity of a family of linearly unstable isolated spherical neutron stars under the effects of very small, perturbations as induced by the truncation error. Using a simple ideal-fluid equation of state we find that this system exhibits a type-I critical behaviour, thus confirming the conclusions reached by Liebling et al. [1] for rotating magnetized stars. Exploiting the relative simplicity of our system, we are able carry out a more in-depth study providing solid evidences of the criticality of this phenomenon and also to give a simple interpretation of the putative critical solution as a spherical solution with the unstable mode being the fundamental F-mode. Hence for any choice of the polytropic constant, the critical solution will distinguish the set of subcritical models migrating to the stable branch of the models of equilibrium from the set of subcritical models collapsing to a black hole. Finally, we study how the dynamics changes when the numerically perturbation is replaced by a finite-size, resolution independent velocity perturbation and show that in such cases a nearly-critical solution can be changed into either a sub or supercritical. The work reported here also lays the basis for the analysis carried in a companion paper, where the critical behaviour in the the head-on collision of two neutron stars is instead considered [2].Comment: 15 pages, 9 figure

Magnetism and structure of LixCoO2 and comparison to NaxCoO2

The magnetic properties and structure of LixCoO2 for x between 0.5 and 1.0 are reported. Co4+ is found to be high-spin in LixCoO2 for x between 0.94 and 1.0 and low-spin for x between 0.50 and 0.78. Weak antiferromagnetic coupling is observed, increasing in strength as more Co4+ is introduced. At an x value of about 0.65, the temperature-independent contribution to the magnetic susceptibility and the electronic contribution to the specific heat are largest. Neutron diffraction analysis reveals that the lithium oxide layer expands perpendicular to the basal plane and the Li ions displace from their ideal octahedral sites with decreasing x. A comparison of the structures of the NaxCoO2 and LixCoO2 systems reveals that the CoO2 layer changes substantially with alkali content in the former but is relatively rigid in the latter. Further, the CoO6 octahedra in LixCoO2 are less distorted than those in NaxCoO2. We postulate that these structural differences strongly influence the physical properties in the two systems

Resistance of sheep to poisoning by the plant, Matricaria nigellifolia DC

The plant, Matricaria nigellifolia, was dosed to 2 sheep to reinvestigate whether or not sheep are susceptible to pushing disease ("stootsiekte"). Each sheep received a total dose of 370 g/kg of the milled, dried plant from a batch that had caused pushing disease in cattle when given at doses as low as 10 g/kg. Neither of the sheep developed clinical disease over the trial period of 60 days, and necropsies revealed no macro- or microscopical lesions. Sheep are apparently resistant to pushing disease, which supports previous findings.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.am201

Evidence of s-wave pairing symmetry in layered superconductor Li0.68_{0.68}NbO2_2 from the specific heat measurement

A high quality superconducting Li$_{0.68}$NbO$_2$ polycrystalline sample was synthesized by deintercalation of Li ions from Li$_{0.93}$NbO$_2$. The field dependent resistivity and specific heat were measured down to 0.5 K. The upper critical field $H_{c2} (T)$ is deduced from the resistivity data and $H_{c2}(0)$ is estimated to be $\sim 2.98$ T. A notable specific heat jump is observed at the superconducting transition temperature $T_c \sim 5.0$ K at zero field. Below $T_c$, the electronic specific heat shows a thermal activated behavior and agrees well with the theoretical result of the BCS s-wave superconductors. It indicates that the superconducting pairing in Li$_{0.68}$NbO$_2$ has s-wave symmetry.Comment: 4 pages, 5 figure

Hepatogenous photosensitivity diseases in South Africa

Various hepatogenous photosensitivity diseases of ruminants in South Africa, caused by plants, fungi and an alga, are described. Information is given on botanical, mycological, toxicological, clinical and pathological aspects of the diseases. The intoxications were grouped according to the primary site of involvement and type of lesions in the liver. The aetiology, pathogenesis, and diagnosis of these conditions received special attention and the most important features are illustrated in colour.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Pathology of a nervous disorder (pushing disease or "stootsiekte") in cattle caused by the plant Matricaria nigellifolia DC. (Asteraceae)

Brains from 10 bovine field cases of pushing disease, a nervous disorder caused by the plant, Matricaria nigellifolia, were examined by light microscopy. Moderate to marked encephalitis, characterized by predominantly perivascular microgliosis, perivascular lymphocytic infiltrates and reactive changes in astrocytes, was present in all the brains. The lesion was concentrated in the white matter throughout the forebrain and midbrain. Dried, milled M. nigellifolia was dosed to 6 steers. Clinical signs of pushing disease, which included docility, clumsiness and pushing against objects, appeared abruptly in 5 of the steers after a latent period that varied from 16-44 days. The lowest total dose of plant that proved toxic was 10 g/kg. The length of the latent period appeared to be related inversely to the total dose. Encephalitis, which was similar in nature and distribution to those in the field cases, was demonstrated in the 5 affected steers. The lesion was minimal in the brain of the steer that did not develop pushing disease. The cerebral lesion is sufficiently consistent and distinctive to be useful in establishing a diagnosis of pushing disease. The perivascular distribution of microgliosis suggests that the site of the toxic insult is the cerebral vasculature. Botanical information is presented.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.am201

An ovine hepatotoxicosis caused by the plant Pteronia pallens (Asteraceae) L.f.

The hepatotoxicity of Pteronia pallens was demonstrated in 5 sheep which developed lesions that ranged from centrilobular necrosis to diffuse hepatocellular degeneration. Botanical, clinical and pathological data are given and the lesions are briefly compared with those caused by other hepatotoxic plants in South Africa.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Photosensitivity in South Africa. VIII. Ovine metabolism of Tribulus terrestris saponins during experimentally induced geeldikkop

Geeldikkop was induced in a sheep by dosing it orally with a crude extract of the steroidal saponins from Tribulus terrestris. GC-MS analysis of the sheep's ruminal contents, bile, faeces and urine for free and conjugated sapogenins, revealed the general features of the metabolic pathway by which diosgenin and yamogenin glycosides were converted into the glucuronides of epismilagenin and episarsasapogenin, the major constituents of the biliary crystals that usually form during geeldikkop. Other steroidal saponins in the T. terrestris extract, including those derived from tigogenin, neotigogenin, gitogenin and neogitogenin, appear to be non-lithogenic. The implications of these findings are discussed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Foundation for Research and Development

e-VLBI observations of GHz-Peaked Spectrum (GPS) radio sources in nearby galaxies from the AT20G survey

GHz-peaked spectrum (GPS) radio sources are thought to be young objects which later evolve into FR-I and FR-II radio galaxies. We have used the Australia Telescope 20GHz (AT20G) survey catalogue to select a uniform sample of GPS sources with spectral peaks above 5GHz, which should represent the youngest members of this class. In this paper, we present e-VLBI observations of ten such objects which are associated with nearby (z<0.15) galaxies and so represent a new population of local, low--power GPS sources. Our e-VLBI observations were carried out at 4.8GHz with the Australia Telescope Long Baseline Array (LBA) using a real--time software correlator. All ten sources were detected, and were unresolved on scales of ~100mas, implying that they are typically less than 100pc in linear size.Comment: 7 pages, 7 figures, 3 table