Neglected vegetative characters in field identification at the supraspecific level in woody plants: phyllotaxy, serial buds, syllepsis and architecture

Some taxonomic characters may escape observation when only a small part of the vegetative body of the plant is examined. For this reason, these characters are likely to be overlooked. Phyllotaxy varies in most cases from the trunk to branches. Serial buds, when they exist, may be lacking in the axil of some leaves. Syllepsis is easier to see on the trunk than on twigs. Architectural models are established after appropriate observation of the whole plant or, better, with different individuals of the same species. Nevertheless, many of these characters can be readily observed and frequently help to identify a woody plant without its flowers or fruits. Some interpretations concerning systematics and evolutionary biology are also given.     

The implications of function on the origin and homologies of the dipterous wing

Abstract The origin of Diptera, and the homologies of the dipteran wing, are re-examined in the light of recent studies on the flight biomechanics and functional wing morphology of Diptera and of Panorpa. Significant Diptera apomorphies are identified, relevant fossils discussed, and a hypothetical wing ground-plan figured.
The arculus, the modified clavus and the anteroposterior asymmetry of the fly wing seem to be adaptations to a mode of flight in which instantaneous wing pitch and camber are controlled automatically, rather than by muscular action; probably in association with the development of asynchronous power musculature.
Tillyard's Cu2 (=CUP) is believed to be a secondary pseudo-vein, his 1A to be the true CuP and 2A to be 1A.
The late Permian fossil Permotipula Patricia is almost certainly a member of the Diptera stem-group, possibly even of the crown-group. The Mesozoic Laurentipteridae and the Permian Permotanyderidae are other possible, but not certain, stem-group members.     

The ecology of the fishes in Nyumba ya Mungu reservoir, Tanzania

Twenty species of fish were found in Nyumba ya Mungu reservoir on the River Pangani which, with two exceptions, were indigenous to the river basin. Their distribution is described and some information on their growth, reproduction and feeding habits is presented. The highest densities of fish were found in the littoral and the broad, shallow, upstream region of the lake. The lacustrine environment has favoured the endemic tilapias, Sarotherodon jipe and S. pangani , which graze periphyton, and the introduced species, S. esculentus which feeds on phytoplankton. Males of the endemic forms may grow to a large size, but the introduced species, including Tilapia rendalli , were heavier for a given length. A reduction in tilapia stocks since 1970 is reflected in experimental catches during 1972-74 and was attributed to the combined effects of heavy commercial exploitation and a loss of spawning grounds. In the same period a striking increase in the populations of small carnivores, Rhabdalestes leleupi and Haplochromis gr. bloyeti , was recorded. Kully plantivorous and piscivorous fish are absent but omnivores are represented by Barbus species and Synodontis punctulatus. Tilapias exhibited a high incidence of nematode infection and the available evidence indicates that fish-eating birds are important predators of cichlids in Nyumba ya Mungu.     

Isolation and characterization of microsatellite markers from the entomopathogenic fungus Metarhizium anisopliae

Fourteen polymorphic microsatellite markers were isolated from the entomopathogenic fungus, Metarhizium anisopliae, based on enriched genomic libraries. In order to assess allelic variability, the microsatellite loci were analysed in a collection of 34 isolates sampled from across Switzerland. The number of detected alleles in 14 loci ranged from two to eight and expected heterozygosity from 0.265 to 0.808. Because of the high expected heterozygosity, the 14 microsatellite loci are very useful for ecological studies and analysis of population diversity, and to identifying, monitoring, and tracking M. anisopliae strains applied as biological control agents.     

The Contribution of TRPV4-Mediated Calcium Signaling to Calcium Homeostasis in Endothelial Cells

A large variety of cation transport systems are involved in the regulation of calcium homeostasis in endothelial cells. The focus of the present study is to determine the contribution of nonselective cation channels from the TRP (transient receptor potential) family to cellular calcium homeostasis of porcine aortic endothelial cells (PAEC). One member of the TRPV (vanniloid) subfamily, TRPV4, has previously been shown to be involved in cation transport induced by a large variety of stimulations including osmolarity, temperature, mechanical stress, and phosphorylation. Here, we demonstrate the existence of several TRP proteins, including TRPV4, in PAEC using RT-PCR. To test whether this channel is functional, we performed FURA-2 calcium measurements and whole-cell patch-clamp experiments. We observed the induction of large calcium signals following mechanical stress, altered extracellular temperature, and the selective TRPV4 activator 4-α -PDD. These effects were diminished in the presence of the TRPV4 inhibitor miconazole, suggesting the involvement of this channel in mediating endothelial calcium signals. The large amounts of transported calcium and the short signaling ways suggest a potentially important role of this channel in many physiological processes.     

Development of novel microsatellite markers for the grassland species Lolium multiflorum,Lolium perenne and Festuca pratensis

Twelve microsatellite markers were isolated from Lolium multiflorum. Allelic variability and cross‐species amplification were assessed on 16 individuals of each of the three grassland species L. multiflorum, Lolium perenne and Festuca pratensis. Cross‐species amplification success was 100% for L. perenne and 83% for F. pratensis. The number of alleles detected ranged from one to 14 with an average of 3.4. While three microsatellite loci were polymorphic in all three species, one marker produced species‐specific alleles in all three species. These microsatellite markers provide a valuable tool for population genetic studies within and among species of the Festuca–Lolium complex.     

Life cycle assessment of biofuels from Jatropha curcas in West Africa: a field study

In recent years, liquid biofuels for transport have benefited from significant political support due to their potential role in curbing climate change and reducing our dependence on fossil fuels. They may also participate to rural development by providing new markets for agricultural production. However, the growth of energy crops has raised concerns due to their high consumption of conventional fuels, fertilizers and pesticides, their impacts on ecosystems and their competition for arable land with food crops. Low-input species such as Jatropha curcas , a perennial, inedible crop well adapted to semiarid regions, has received much interest as a new alternative for biofuel production, minimizing adverse effects on the environment and food supply. Here, we used life-cycle assessment to quantify the benefits of J. curcas biofuel production in West Africa in terms of greenhouse gas emissions and fossil energy use, compared with fossil diesel fuel and other biofuels. Biodiesel from J. curcas has a much higher performance than current biofuels, relative to oil-derived diesel fuels. Under West Africa conditions, J. curcas biodiesel allows a 72% saving in greenhouse gas emissions compared with conventional diesel fuel, and its energy yield (the ratio of biodiesel energy output to fossil energy input) is 4.7. J. curcas production studied is eco-compatible for the impacts under consideration and fits into the context of sustainable development.     

Restoring freshwater ecosystems in riverine landscapes: the roles of connectivity and recovery processes

1. This paper introduces key messages from a number of papers emanating from the Second International Symposium on Riverine Landscapes held in August 2004 in Sweden, focusing on river restoration. Together these papers provide an overview of the science of river restoration, and point out future research needs. 2. Restoration tests the feasibility of recreating complex ecosystems from more simple and degraded states, thereby presenting a major challenge to ecological science. Therefore, close cooperation between practitioners and scientists would be beneficial, but most river restoration projects are currently performed with little or no scientific involvement. 3. Key messages emanating from this series of papers are: The scope, i.e. the maximum and minimum spatial extent and temporal duration of habitat use, of species targeted for restoration should be acknowledged, so that all relevant stages in their life cycles are considered. Species that have been lost from a stream cannot be assumed to recolonise spontaneously, calling for strategies to ensure the return of target species to be integrated into projects. Possible effects of invasive exotic species also need to be incorporated into project plans, either to minimise the impact of exotics, or to modify the expected outcome of restoration in cases where extirpation of exotics is impractical. 4. Restoration of important ecological processes often implies improving connectivity of the stream. For example, longitudinal and lateral connectivity can be enhanced by restoring fluvial dynamics on flood‐suppressed rivers and by increasing water availability in rivers subject to water diversion or withdrawal, thereby increasing habitat and species diversity. Restoring links between surface and ground water flow enhances vertical connectivity and communities associated with the hyporheic zone. 5. Future restoration schemes should consider where in the catchment to locate projects to make restoration most effective, consider the cumulative effects of many small projects, and evaluate the potential to restore ecosystem processes under highly constrained conditions such as in urban areas. Moreover, restoration projects should be properly monitored to assess whether restoration has been successful, thus enabling adaptive management and learning for the future from both successful and unsuccessful restorations.