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Phytophthora andina is a heterothallic plant pathogen of Andean solanaceous hosts and is an interspecific hybrid of P. infestans and an unknown Phytophthora species. The objective of this study was to estimate the nuclear DNA content of isolates in three clonal lineages of P. andina relative to P. infestans Twelve isolates of P. andina and six isolates of P. infestans were measured for nuclear DNA content by propidium iodide-stained flow cytometry. We found that the DNA content of P. andina was similar but slightly smaller, on average, than that of our sample of P. infestans isolates. This is consistent with P. andina being a homoploid hybrid rather than allopolyploid hybrid. Nuclear DNA content was more variable among a smaller sample of P. infestans isolates, including a putative triploid isolate from Mexico, but small differences in nuclear DNA content were also observed among P. andina isolates. Both species appear to be able to tolerate significant variation in genome size.

Pythiosis is a deadly disease of horses, dogs, and other mammals, including humans, in tropical and subtropical regions. In the United States, the disease has been reported in the Southeast as well as in the temperate North and the dry Southwest. The causal agent of pythiosis is Pythium insidiosum, one of few mammalian pathogens in the fungus-like Oomycetes. P. insidiosum has not been studied in the environment in the United States. Given anecdotal reports of pythiosis in Gainesville, Florida dogs, we hypothesized that warm standing water in lakes and ponds in North Central Florida is suitable habitat for P. insidiosum. We sampled 19 lakes or ponds to examine the environmental distribution of P. insidiosum and to determine which of the three previously described genetic clusters of P. insidiosum are present. We found P. insidiosum in 11 of the sampled lakes and ponds. Sequencing of the ITS region separated isolates into three genetic clusters, including a distinct group previously represented by a single isolate from South Carolina. AFLP genotyping of isolates showed genetic variation in Cluster I, which is the group associated with the majority of characterized clinical isolates from the Americas. Our results indicate that animal exposure to P. insidiosum in North Central Florida is common. This study provides the first evidence that P. insidiosum may be more widely distributed in freshwater lakes and ponds in the Southeastern United States than previously appreciated.

During the startup phase of the thorium high-temperature reactor (THTR)-300, control rod reactivity measurements are performed to meet the demands of the licensing authorities as well as to adjust ...

In a sample of 106Σ+ hyperons we have searched for the decaysσ+→ ne+ν andσ+→nμ+ν, which would violate theΔQ=ΔS rule. NoΣ+→ne+ν decay was found, whereas 313σ−→ne−ν decays were identified in the same film. With 90% confidence we obtain $$\frac{{\Gamma (\sum ^ + \to ne^ + v)}}{{\Gamma (\sum ^ - \to ne^ - \bar v)}} \leqq 3.10^{ - 2} .$$

We have found a possible example of the rare decayσ+→nΜ+Ν, which violatesδS=δQ. The positive decay track of theσ+ comes to rest in the hydrogen bubble chamber and decays into ane+. This track has all the characteristics of a stoppingΜ+. The decay neutron fortuitously scatters twice, producing two recoil protons. The only other possible interpretation of the event isσ+→nγ(π+→Μ+Ν), where theπ+→Μ+Ν decay produces no deflection (θ

The decay modesΣ±→nπ±γ, Σ+→pγ,Σ+→pe+e}- were studied in the 81 cm Saclay hydrogen bubble chamber. In the radiative decayΣ±→nπ±γ only low momentum pions which stop in the chamber were accepted.

The ratio of the axial-vector to vector coupling constant, ¦g 1/f 1¦, in theΣ −→ne − $$\bar v$$ decay was determined from the electron-neutrino angular distribution. In a sample of 454Σ −→ne − $$\bar v$$ decays a search was made for subsequent neutron proton scattering in order to detect the decay neutrons. TheΣ hyperons were produced by stoppingK −-mesons in the 81 cm Saclay hydrogen bubble chamber. For the kinematical analysis 33Σ −→ne − ν events with associatednp→np interactions were accepted. The value ¦g 1/f 1¦=0.37 −0.19 +0.26 was obtained.

From about 2 × 106 measured ∑± decay's produced by stoppingK− mesons in the 81 cm Saclay hydrogen bubble chamber about 140,000 ∑− →n π− and 20,000 ∑+ →nπ+ decays were selected for a lifetime measurement. We obtained: $$\begin{gathered} \tau _{\Sigma ^ + } = (0.795 \pm 0.010) \times 10^{ - 10} \sec \hfill \\ \tau _{\Sigma ^ - } = (1.485 \pm 0.022) \times 10^{ - 10} \sec . \hfill \\ \end{gathered} $$

All experimental data on leptonic decays of Baryons available after the Kiev Conference on High Energy Physics (Sept. 1970) are used to fit the parameters of the Cabibbo theory. Especially new results on σ− and Λ leptonic decays and the values of the Σ± lifetime are included.

From about 6×106 stoppingK−-meson reactions in the Saclay 80 cm hydrogen bubble chamber 70Σ−→Λe−¯ν and 11Σ+→Λe+ν decays have been identified. The ratio of the vector to axial vector coupling constant has been determined,f1/g1=−0.22±0.28, consistent with the predictionf1=0 of the CVC-theory. The branching ratios for the two decay modes are,Γ(Σ−→Λe−ν)/Γ(Σ−→ all modes)=(0.69±0.12). 10−4,Γ(Σ+→Λe+ν)/Γ(Σ+→ all modes)=(0.29±0.10). 10−4. The ratio, Γ(Σ+→Λe+)/Γ(Σ−→Λe−v)=0.69±0.18, agrees with the phase space ratio, 0.61, therefore a theory that includes no second class currents is consistent with the data.

Es wurde uber eine schwerste todliche Vergiftung nach subkutaner Injektion von Thermometerquecksilber berichtet. Die Einbringung des mit Blei verunreinigten Quecksilbers hatte eine akute, gelbe Leberdystrophie zur Folge. In der Bleiverunreinigung des Quecksilbers wurde ein Umstand ersehen, der als wesentlich fur die Schwere der Erkrankung und den Umfang der Organveranderungen angesprochen wurde.

New measurements of baryon leptonic decay rates and formfactor ratios make a new comparison with the Cabibbo theory desirable.

Approximately 106 Σ± decays of the stopping K− film (80 cm Saclay HBC) have been measured with the Heidelberg KONRAD-system1. This system is capable of detecting about 75% of the Σ−→ ne−¯v decays. In addition, about 106 pictures have been scanned for Σ± leptonic decays with secondary particle momenta below 80 MeV/c. This covers about 15% of the lepton spectrum. The data yield the following branching ratios

In February and March 1981, eight patients and two nurses in a women's ward (internal medicine) fell ill with gastroenteritis. Because faecal samples were not available during the acute phase, the diagnosis was made by demonstrating complement-binding antibodies and rotavirus-specific IgM, with 14 persons on the same ward without gastroenteritis serving as controls. The illness took a mild course. All patients had watery diarrhoea and abdominal pain, four had nausea or vomiting, but only one had fever. Thus even in adults with gastroenteritis rotavirus infection should be considered in the differential diagnosis.

The electrical characteristics and monochromatic power efficiency are given for the first singlet state-driven photogalvanic cell which is based on the photoreduction of the title dye by iron(II) with spontaneous regeneration of the dye and iron(II) from the charge carriers leuco-oxonine and iron(III) at the anode and cathode respectively.