The Gamete Pigments of Hormosira banksii (Phaeophyta)

The gamete pigments of Hormosira banksii have been separatedby thin-layer chromatography and identified by absorption spectrophotometry.Male gametes contain predominantly ß-carotene, andfemale gametes predominantly chlorophyll and fucoxanthin. Severalminor pigments have also been tentatively identified.     

Respiratory Characteristics of Isolated Barley Mitochondria and Intact Barley Roots

Purified mitochondria were prepared from roots of 7- and 14-d-oldbarley plants and their respiratory activities were determined.The following observations were made. (1) With age, total oxygenuptake declined in the intact root and in isolated root mitochondria.(2) The alternative pathway was present and engaged to 60% ofits capacity in the intact roots of both 7- and 14- d-old plants.In the isolated mitochondria its activity depended on the substrateused. (3) State 4 respiration rates were high in the isolatedmitochondria, but there was little contribution by the alternativeoxidase. The implications of these findings are discussed. Itis proposed that mitochondrial respiratory capacity plays animportant role in determining the respiration rate of the intactbarley root. Key words: Mitochondria, cytochrome path, alternative path, roots, barley     

Effectiveness of Lethal,Directed Wolf-Depredation Control in Minnesota

Abstract: Wolf (Canis lupus) depredations on livestock in Minnesota, USA, are an economic problem for many livestock producers, and depredating wolves are lethally controlled. We sought to determine the effectiveness of lethal control through the analysis of data from 923 government-verified wolf depredations from 1979 to 1998. We analyzed the data by 1) assessing the correlations between the number of wolves killed in response to depredations with number of depredations the following year at state and local levels, and 2) the time to the next depredation. No analysis indicated that trapping wolves substantially reduced the following year's depredations at state or local levels. However, more specific analyses indicated that in certain situations, killing wolves was more effective than no action (i.e., not trapping). For example, trapping and killing adult males decreased the re-depredation risk. At sheep farms, killing wolves was generally effective. Attempting to trap, regardless of the results, seemed more effective at reducing depredations than not trapping, suggesting that mere human activity near depredation sites might deter future depredations. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):778–784; 2008)     

Detection of Intraspecific DNA Content Variation in Zea mays L. by Flow Cytometry

Flow cytometry was used to determine quantitative intraspecificDNA content variation in Zea mays. Previous studies using flowcytometry had indicated that intraspecific variation in cornwas beyond the resolution of the method. The DNA content variationamong corn lines observed in this study was in agreement withthe amount of variation observed using microdensitometry. Inorder to observe intraspecific variation, the fluorochrome DAPIwas shown to be superior to mithramycin. The fluorochrome: nucleiratio was found to be critical when DAPI was used because ofself absorption of the fluorescence. Flow cytometry with thefluorochrome DAPI was found to be a rapid and reliable alternativeto microdensitometry in examining intraspecific DNA contentvariation in corn. Key words: Genome size, corn (maize), Zea mays, DAPI     

Fine Structure of a New Human Microsporidian, Encephalitozoon hellem, in Culture

Encephalitozoon hellem is a new human microsporidian isolated from corneal biopsies and conjunctival scrapings of three AIDS patients and cultured in Madin Darby canine kidney (MDCK) cells. Encephalitozoon hellem and Encephalitozoon cuniculi display different protein profiles with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and unique antibody binding patterns with murine antisera against Western blots of each organism. Developmental stages of E. hellem in culture are similar to E. cuniculi. Meronts are 1.3–2.7 μm in diameter, develop within a parasitophorous vacuole adjacent to the vacuolar membrane, divide by binary fission, and contain one or two discrete nuclei. Sporonts measure 2 × 3 μm, separate from the vacuolar membrane, and have a thickened outer membrane. Sporoblasts display a tri-layered wall and possess the earliest recognized polar filaments. Mature spores measure 1 × 1.5 μm and are more electron-dense than other stages. Each spore contains a single nucleus, a polar tubule with four to nine coils, thin electron-dense exospore and thick, electron-lucent endospore. Although E. hellem and E. cuniculi differ biochemically and immunologically, their fine structure and development are indistinguishable.     

Do Rocks Listen?

This essay attempts to show the competing cultural frameworks involved in the (e)valuation of Aboriginal work in the context of the Dreaming and development, juxtaposing Western and Belyuen ways of understanding what happens when humans act in the natural environment and their economic and politico-jural consequences. To do so, it critically opposes political-economic assumptions about the alleged divide between human subject-agents, nonintentional animal appropriators, and objects, and between cultural belief and economic-ecological reality. In this way we can begin to apprehend Aboriginal labor without aiding and abetting the state on the dispossession of Aboriginal lands and delegitimization of Aboriginal beliefs.     

Fat Metabolism in Germinating Citrullus vulgaris. Part II

Breakdown of fat in watermelon seedlings germinated in the darkoccurs in essentially the same way as in the light. Free fattyacids do not accumulate and the composition of the lipid remainsalmost unchanged during its rapid utilization. The low weight of ‘protoplasmic lipid’ remainingin the etiolated cotyledons after the storage fat has disappearedcontains a lower proportion of linolenic acid than that fromgreen cotyledons of a corresponding age. The weight of phosphatide (lipid P) per cotyledon increases both in light- anddark-grown seedlings until 8 days, thereafter declining in thedark but continuing to rise in the light. Phosphatide and glyceridefractions from the same fat resemble each other fairly closelyin fatty acid composition.