Coronary arteries of the roe deer (Capreolus capreolus; Linnaeus 1758) heart

A study of the coronary arteries of the roe deer heart was performed on 21 hearts of animals of both sexes and various ages. The roe deer heart is supplied by two arteries: the left coronary artery and the right coronary artery. The left coronary artery arises from the left aortic sinus and forms a short common trunk. The left coronary artery reaches the coronary groove, then divides into the paraconal interventricular branch and the circumflex branch. The circumflex branch gives off several branches to the left ventricle wall and terminates in the subsinuosal interventricular groove as the subsinuosal interventricular branch. The right coronary artery is less pronounced than the left coronary artery. It arises from the right aortic sinus and enters the coronary groove as the right circumflex branch. We found the left arterial cone branch in 75% and the right arterial cone branch in 80% of the cases investigated. The coronary arteries of the heart run subepicardially. In 9 cases we found muscular bridges over the coronary arteries, mostly on the paraconal interventricular branch. In conclusion we affirm the left type of the arterial vascularisation in the roe deer heart.     

Einfluß von Zwei- und Dreischichttonmineralen auf die Dehydrogenase-, saure Phosphatase- und Urease-Aktivität in Modellversuchen

Influence of two- and three-layered clay minerals on the Dehydrogenase-, acid Phosphatase and Urease Activity in model experiments The influence of different Ca-homo-ionic clay minerals as well as humic acid (Roth) on the dehydrogenase activity (DHA) as well as on urease and acid phosphatase were examined in model experiments. The following results were obtained: 1. The DHA of a fertile soil and the activity of urease and acid-phosphatase decreased remarkably and specifically with increasing amounts of sorbents. Generally speaking, inactivation was complete at approximately 0.6 g of each additive. Both urease- and acid phosphatase activity were inactivated specifically. The inactivation of urease decreased in the sequence humic acid < montmorillonite < illite < pyrophyllite < halloysite < kaolinite < bentonite, whereas the following order of succession pyrophyllite < montmorillonite < bentonite < halloysite < kaolinite < illite was recorded with acid phosphatase. The yellow colour of humic acid excluded it from experiments with acid phosphatase. 2. No relationship could be found between the degree of inactivation and the cation exchange capacity (CEC) or the total surface area of the clays. However, nearly the same sequence of inactivation with the three enzyme systems was revealed, if their activity was related to the specific surface charge of the clay minerals. Apparently, both the total surface area as well as CEC are involved in the specific sorption of cells and enzymes. The possible mechanisms of sorption on clay surfaces are discussed.     

Impact of allelochemical exuded from allelopathic rice on soil microbial community

Allelopathic rice releases allelochemicals from its roots to paddy soils at early growth stages to inhibit neighboring weeds. However, little is currently known about the effects of allelochemicals on soil microbes. In this study, we show that allelopathic rice can have great impact on the population and community structure of soil microbes. Allelopathic rice PI312777 seedlings reduced the culturable microbial population and total PLFA when compared to non-allelopathic rice Liaojing-9. Similar results were observed when, instead of growing seedlings, soils were incubated with plant root exudates. This result demonstrates that the composition of root exudates from the rice varieties tested contributes to the soil microbial community. Further experiments showed that the microbial community was affected by the allelochemical 5,4′-dihydroxy-3′,5′-dimethoxy-7-O-β-glucopyranosylflavone exuded from allelopathic rice roots, through immediately hydrolyzing glucose with stimulation on soil bacteria and aglycone (5,7,4′-trihydroxy-3′,5′-dimethoxyflavone) with inhibition on soil fungi. This result indicates that the flavone O-glycoside can provide carbon and interact with soil microbes. PC analysis of the fatty acid data clearly separated the allelopathic PI312777 and the non-allelopathic Liaojing-9 variety (PC1 = 46.4%, PC2 = 20.3%). Similarly, the first principal component (PC1 = 37.4%) together with the second principal component (PC2 = 17.3%) explained 54.7% of the variation between the allelopathic and non-allelopathic root exudates. Furthermore, the canonical correlation between allelopathic root exudates and the flavone O-glycoside was statistically significant (Canonical R = 0.889, χ² (25) = 69.72, p = 0.0041). Although the data generated in this study were not completely consistent between culturable microbes and PLFA profile, it is a fact that variation in soil microbial populations and community structures could be distinguished by the allelopathic and non-allelopathic rice varieties tested. Our results suggest that individual components of rice root exudates, such as allelochemicals from allelopathic rice, can modify the soil microbial community.     

Vegetation and Environment in Afforested Sand Dunes at Newborough, Anglesey

Newborough Forest was planted with pines, chiefly Corsican pine,during the period 1947–65. In 1986, its soils and vegetationwere surveyed and related to the preplanting condition of thedunes, inferred from air photographs. The youngest dunes contained4 per cent calcium carbonate in the top 30cm; the oldest wereacid, with no free calcium carbonate. There was little acidificationof the soil and no extra leaching of calcium carbonate due tothe pines. Vegetation under trees varied according to the ageand pH of the dunes. Young dunes were almost bare except formoss; older dunes had been colonized by ferns and brambles.All plant species of the original open dune system had apparentlysurvived in unplanted slacks or on road verges; some had increased.Many new species had invaded, including woodland mosses, ferns,orchids and two species of Pyrola.     

Precursors to damascenone: synthesis and hydrolysis of isomeric 3,9-dihydroxymegastigma-4,6,7-trienes

A series of four isomeric 3,9-dihydroxymegastigma-4,6,7-trienes, 8, has been prepared. The (3S,6R,9S) isomer of 8 proved to be identical to an isomer of this compound tentatively identified as an intermediate in the formation of damascenone from an allene triol. Each of the four isomers, when hydrolyzed independently of each other at pH 3.0 and 25 degrees C, produced product mixtures in which the major product was damascenone (1). Contrary to expectation, 3-hydroxydamascone (5) was not observed in any of the hydrolyses. Consequently, the mechanism of formation of damascenone proposed earlier requires modification. In each hydrolysis, the product mixtures showed the presence of a second isomer of 8, produced by epimerization during hydrolysis. Chiral analysis on a Cyclosil B column revealed that this epimerization was occurring at C(3) in each of the hydrolyses.     

Effect of imazamox plus bentazon on dry bean (Phaseolus vulgaris L.)

Imazamox plus bentazon has the potential to provide broad spectrum weed control in dry bean (Phaseolus vulgaris L.). Field trials were conducted in Ontario over a two year period (2003 and 2006) to evaluate the effect of imazamox plus bentazon applied post-emergence at 25 + 600 and 50 + 1200 g ai ha⁻¹ on black, brown, cranberry, kidney, otebo, pinto, white and yellow eye beans. Treatments included a non-treated check. All treatments were maintained weed free during the growing season. The eight market classes responded similarly to imazamox plus bentazon. Imazamox plus bentazon applied post-emergence caused less than 4% visible injury at 7, 14 and 28 days after treatment. Imazamox plus bentazon applied post-emergence did not have any effect on plant height, shoot dry weight, seed moisture content and yield of dry bean. Based on these results, imazamox plus bentazon at the proposed maximum use dose can be safely used for weed management in black, brown, cranberry, kidney, otebo, pinto, white and yellow eye bean production in Ontario. Additional research is needed to determine if cultivars within a market class of dry bean differ in their response to imazamox plus bentazon.     

Survival of the western pond turtle (Emys marmorata) in an urban California environment

The western pond turtle Emys (formerly Clemmys) marmorata is declining throughout its range, primarily due to loss of habitat via urbanization and conversion to agriculture. Urban waterways present several important challenges to freshwater turtle populations, but they also present an opportunity to maintain declining species in a ubiquitous habitat that has high public visibility. The arboretum waterway on the University of California, Davis campus is an example of an extensively altered urban habitat that supports a relatively large E. marmorata population. Over the last 6 years, we monitored the turtle population inhabiting the arboretum waterway to determine the demographic health of the population, and the challenges and opportunities that urban environments pose for pond turtles. Since 1993, the naturally existing arboretum pond turtle population has declined by approximately 40% and has shown little natural recruitment. During this time, we also introduced 31 headstarted turtles into the arboretum. Headstarting is the process of raising juveniles in captivity until they have outgrown their period of greatest vulnerability to predators, and then releasing them into the wild. Our headstarting results demonstrate that this contentious strategy is a viable option for adding young turtles to the population, although it does not address the causes of decline. Over the course of our study, we encountered nine species of non-native turtles in the waterway, and these appear to be a serious threat to the native species. As more habitat becomes urbanized, it is increasingly important to understand how freshwater turtles, such as E. marmorata, adapt to urban waterways and the impact of non-native turtles on native turtle species. Our strong feeling is that urban waterways can provide habitat for viable populations of freshwater turtles and showcase them to the public, but both the aquatic and terrestrial habitat must be managed according to the biological requirements of individual species.