The phylogeny and systematics of European predacious Syrphidae (Diptera) based on larval and puparial stages

The external larval morphology of predacious Syrphidae is examined and compared with that of other groups of syrphids. Predacious larvae form a distinctive, monophyletic group. Relationships among 29 of the 34 European genera and subgenera are analysed using cladistic methods based on larval and puparial characters. Interpretation of the cladogram suggests that, within Syrphinae, a system of five tribes can be recognized and that a major trend has been a shift from ground layer to arboreal larval habitats, with an increasing degree of obligate dependence on soft-bodied Homoptera as prey. Generic diagnoses with biological and taxonomic notes are given and a key to genera based on larvae and puparia is provided.     

The effect of the release of an artificial discharge of water on invertebrate drift in the R. Wye,Wales

An artificial discharge of water (3.0 m³/sec), over a 48 h period, from an impoundment into the R. Wye did not substantially affect water temperature or concentrations of dissolved oxygen and suspended solids at a site 16 km below the impoundment. However, the load of suspended material on the second day of the release was about 10 times greater than the pre-release load. The total number of drifting macroinvertebrates on the first and second days of the release were about 7 and 3 times greater than the number on the day preceding the release. The initial increase in flow at 15.00 h resulted in an immediate increase in the number of drifting larvae of Rheotanytarsus, a tubicolous chironomid. Subsequently there was an enhanced night-time increase in the total number of drifting invertebrates, particularly the mayfly, Ephemerella ignita (Poda), and this also occurred on the second night of the release. Increases in the number of drifting Rheotanytarsus and Ephemerella, the most abundant invertebrates, resulted in increase in drift density.Authors' address Llysdinam Field Centre, UWIST, Newbridge-on-Wye, Llandrindod Wells, Powys, Wales.     

A glance into the vegetation and settlement of the fortress islands of Suomenlinna,Helsinki.: Pollen analytical study

Pollen studies were carried out of the sediments from a small pond on Susisaari, the largest island of the fortress of Suomenlinna, Helsinki. Three cores with altogether 80 samples were analysed, but only one core being reported here and additional comments are given on the results from two other cores. As it is most probable that the material has been mixed in several constructional phases during the last 100-200 years, the results were interpreted as one unit representing aerial and local vegetation during approximately that period. The results were compared with the recent vegetation, with the history of imported species, and with three botanical inventories made on the islands during the 20th century. Differences in pollen production and in pollen dispersal properties of different species strongly affect the results.     

Land use change in the Amazon estuary: Patterns of caboclo settlement and landscape management

Landsat TM scenes for 1985 and 1991 are used to produce a georeferenced map of land cover and land use for an area of the Amazon estuary inhabited by three populations of caboclos with distinct patterns of land use. This information is combined in a geographic information system with ethnographic and survey research carried out over the past 5 years to develop representative spectral signatures which permit measurement and differentiation of land uses and the detection of change even between small areas of managed floodplain forest and unmanaged forest, and between three distinct age/growth classes of secondary succession following deforestation. Implementation of these procedures permit the scaling up or down of research at different resolutions. Three distinct patterns of land use are examined with differential impact on the environment. Mechanized agriculture at one site has eliminated virtually all the mature upland forest and is now dominated by secondary successional vegetation. The more traditional system of diversified land use at the next site shows a subtle cycling of flooded forest to managed palm forest through time in response to the price of palm fruit and cycling in the use of fallow land. A third site, based on palm fruit extractivism, shows minimal changes in land cover due to persistent specialization on management of flooded forest extraction. There is little evidence that the community with the greatest impact on forest cover is any better off economically than the two communities which have minimal impact on the landscape. This study suggests how a balance between use and conservation in Amazonia may be achieved in floodplain and estuarine areas, and the effectiveness of monitoring these types of land cover from satellite platforms.     

Mites of the family Hyadesiidae (Acari: Astigmata) from New Zealand

Keys are provided to families of Hyadesioidea, to genera of Hyadesiidae, and to all species of this family known from the New Zealand subregion. A new species of Amhyadesia , two new species of Hyadesia sensu stricto , and four new species of a newly defined subgenus of Hyadesia (Parahyadesia) are described.     

Bile acid and cholesterol excretion in the pregnant guinea pig: Studies on the hypercholesterolemia of pregnancy

The relationship of bile acid and cholesterol excretion to changes in plasma cholesterol during pregnancy were studied in guinea pigs. Plasma cholesterol level increased in the first trimester of pregnancy, reached to a peak during the second trimester and decreased in the third trimester reaching the lowest level at one week prior to parturition. Cholesterol level returned to the control level after parturition. Plasma triglyceride level followed a similar trend attaining peak values at second trimester and gradually returned to the control level at the third trimester of pregnancy. Bile acid and total sterol excretion were significantly higher in guinea pigs during the last phase of pregnancy while they remained unchanged during early stage of pregnancy.     

Membrane potential and surface charge densities as possible generalized regulators of membrane protein activities

On the basis of experimental evidence accumulated in studies of coupling and other membranes a theoretical discussion of a “breathing” membrane structure dependent upon a changing transmembrane electrical (electrochemical) gradient is presented. In the case of certain membranes difference of electrical potentials across the membrane (Δψ) is considered as one of important driving forces for some membrane protein folding and/or the arrangement of subunits within some oligomeric proteins. Δψ changes may induce synchronous reversible energetically favourable transitions in the three-dimensional architecture of several spatially separated proteins of the biomembrane. A polyfunctional regulation of levels of activities of spatially separated membrane proteins may be achieved; in some cases alterations of Δψ and surface charge densities may fulfil function of a link in the chain of events triggering membrane-bound activities in response to external stimuli.     

Activation of the contractile system in crustacean muscle: Ultrastructural evidence for the role of the T system

Freeze-fracture and thin sections of lobster abdominal fast flexor muscle were used to study the morphology of the sarcoplasmic reticulum (SR) and T system of crustacean muscle. Tannic acid mordanting, which can result in a dense black deposit in the T system lumen, was used to distinguish T system from SR membranes. Ferritin was also used as an extracellular tracer to confirm the tannic acid method. The T system consists of an extensive network of flattened sacs which fills most of the space between the mycfibrils and is in close contact with them. The SR also appears as flattened sacs, sometimes with fenestrations. There is extensive junctional contact between the SR and T system. Quantitative estimates of the volume and surface area of the membranes show that the T system has about 50 % more surface area than the SR. The intramembrane particle (IMP) density of the PF face of the T system is about 1100/ μm² membrane, while the IMP density of the PF face of the SR is about 4800/ μm² membrane. In morphology, extent, and IMP density, the T system of lobster abdominal fast flexor muscle appears (AFF) adapted to provide at least part of the Ca²⁺ for muscle activation and the transport system for relaxation.     

Studies on the patterns of nitrogen uptake and translocation to the grain of winter barley intended for malting

In five experiments carried out between 1987 and 1989, crops of winter barley were grown under a range of agronomic treatments to study the way the treatments influenced the patterns of nitrogen uptake, dry matter production, translocation of assimilates and malting quality. Rate and timing of nitrogen fertiliser had large effects. Increased and late applications invariably increased nitrogen concentration in the grain by affecting the partitioning of nitrogen between the vegetative and reproductive parts of the plant. Foliar fungal diseases also affected nitrogen partitioning, apparently by interfering with the transport of stored nitrogen to the developing grain. Seasonal influences, especially rainfall during the grain filling period, were found to have profound effects on the pattern of change in ear and grain nitrogen concentration, and hence malting quality. The ability to predict final grain nitrogen concentration from measurements made earlier in the season is not therefore likely to be feasible.     

Differences in Englemann Spruce Forest Biogeochemistry East and West of the Continental Divide in Colorado, USA

We compared Englemann spruce biogeochemical processes in forest stands east and west of the Continental Divide in the Colorado Front Range. The divide forms a natural barrier for air pollutants such that nitrogen (N) emissions from the agricultural and urban areas of the South Platte River Basin are transported via upslope winds to high elevations on the east side but rarely cross over to the west side. Because there are far fewer emissions sources to the west, atmospheric N deposition is 1–2 kg N ha⁻¹ y⁻¹ on the west side, as compared with 3–5 kg N ha⁻¹ y⁻¹ on the east side. Species composition, elevation, aspect, parent material, site history, and climate were matched as closely as possible across six east and six west side old-growth forest stands. Higher N deposition sites had significantly lower organic horizon C:N and lignin:N ratios, lower foliar C:N ratios, as well as greater %N, higher N:Ca, N:Mg, and N:P ratios, and higher potential net mineralization rates. When C:N ratios dropped below 29, as they did in east-side organic horizon soils, mineralization rates increased linearly. Our results are comparable to those from studies of the northeastern United States and Europe that have found changes in forest biogeochemistry in response to N deposition inputs between 3 and 60 kg ha⁻¹ y⁻¹. Though they are low by comparison with more densely populated and agricultural regions, current levels of N deposition, have caused measurable changes in Englemann spruce forest biogeochemistry east of the Continental Divide in Colorado. Received 22 January 2001; accepted 11 June 2001.     

Suppression of In Vivo Neostriatal Acetylcholine Release by Vesamicol: Evidence for a Functional Role of Vesamicol Receptors in Brain

Experiments examined the effects of peripheral and central administration of the vesicular acetylcholine transport blocker vesamicol (AH5183) on the content, synthesis, and release of acetylcholine in the rat brain in vivo. In time course studies, a single intraperitoneal dose of DL-vesamicol (5 mg/kg) rapidly and reversibly (within 2 h) doubled the content of acetylcholine in the striatum and hippocampus, without affecting choline levels or the rate of transmitter synthesis. In microdialysis experiments, the same peripheral dose of drug produced a reversible 55% reduction in endogenous striatal acetylcholine release. A similar inhibitory effect was produced by direct intrastriatal perfusion with vesamicol. Moreover, this effect of vesamicol was (a) concentration-dependent and saturable (EC50 = 68 nM), (b) rapidly reversible, (c) stereospecific for the L-isomer, and (d) poorly mimicked by a vesamicol analog with lower plasma membrane permeability. This profile of effects is consistent with an interaction with a specific vesamicol receptor as defined by previous in vitro binding studies. These results support a functional role for vesamicol receptors in modulating central cholinergic transmission in vivo.     

Diploid and autotetraploid sexuals and their relationships to apomicts in the Ranunculus cassubicus group: insights from DNA content and isozyme variation

 From the predominantly aposporous Ranunculus cassubicus group, a subgroup of the R. auricomus complex, two species with both diploid and tetraploid cytodemes (R. cassubicifolius W. Koch and R. carpaticola Soó) were known. Nine population samples of both species have been analyzed for variation of ploidy levels and isozymes. DNA image analysis showed that three populations of R. cassubicifolius from Bavaria and Salzburg are diploid, two from Lower Austria tetraploid. In R. carpaticola, two populations from Central Slovakia and one from Romania are diploid, one from northern Slovakia is hexaploid. The polyploid populations had somewhat smaller C-values than expected from diploids. Ploidy levels are consistent within populations, contradicting previous hypotheses that cycles of diploid-tetra-ploid-dihaploid apomictic individuals occur in natural populations of goldilocks. Isozyme-allozyme analysis of nine polymorphic loci showed that individual variation and genetic measures of di-ploid and tetraploid populations are equivalent to those of sexual taxa. Multiple allelism and unbalanced gene dosages in tetraploid R. cassubicifolius give evidence for autopolyploidy that is most probably of multiple origin. The observed excess of homozygotes and the high diversity between populations in the diploid populations of R. cassubicifolius are most probably due to geographical isolation of population groups, that might have happened during the Würm glaciation and might have promoted the separation of autotetraploids in the easternmost part of the distribution range. Genetic distance values analyzed by UPGMA of all sexual populations separated the two taxa and the cytodemes within R. cassubicifolius. Multidimensional scaling of individuals (including the apomicts) based on a presence/absence matrix of alleles confirmed this differentiation with an overlapping zone between R. cassubicifolius and R. carpaticola. The hexaploid R. carpaticola population showed reduced genotypic diversity, an increased number of heterozygotes and fixed heterozygosity as typical for apomictic mode of reproduction. This population shared alleles of both species without any specific ones, multidimensional scaling placed genotypes among R. cassubicifolius. Thus, the hexa-ploid apomicts might have originated from hybrids of R. cassubicifolius and R. carpaticola. In general, evolution of agamic lineages in the R. cassubicus complex might have been facilitated by autopoly-ploids, because they can provide a bridge between the reproductive systems that are otherwise isolated by ploidy levels, and also a starting point for spontaneous origin of apomixis. Received October 8, 2001; accepted May 10, 2002 Published online: November 7, 2002 Addresses of the authors: Elvia H?randl (E-mail: elvira.hoerandl@univie.ac.at), Department of Systematics and Evolution of Higher Plants; Johann Greilhuber (E-mail: Johann.Greilhuber@univie. ac.at), Department of Systematic Karyology and Embryology of Plants; both: Institute of Botany, University of Vienna, Rennweg 14, A-1030 Vienna, Austria.     

Modelling cereal root systems for water and nitrogen capture: towards an economic optimum

A quantitative model of wheat root systems is developed that links the size and distribution of the root system to the capture of water and nitrogen (which are assumed to be evenly distributed with depth) during grain filling, and allows estimates of the economic consequences of this capture to be assessed. A particular feature of the model is its use of summarizing concepts, and reliance on only the minimum number of parameters (each with a clear biological meaning). The model is then used to provide an economic sensitivity analysis of possible target characteristics for manipulating root systems. These characteristics were: root distribution with depth, proportional dry matter partitioning to roots, resource capture coefficients, shoot dry weight at anthesis, specific root weight and water use efficiency. From the current estimates of parameters it is concluded that a larger investment by the crop in fine roots at depth in the soil, and less proliferation of roots in surface layers, would improve yields by accessing extra resources. The economic return on investment in roots for water capture was twice that of the same amount invested for nitrogen capture.     

Larval development of the chthamaloid barnacles Catomerus polymerus Darwin, Chamaesipho tasmanica Foster & Anderson and Chthamulus antennatus Darwin (Crustacea: Girripedia)

The presence of embryos in the mantle cavity of Catomerus polymerus, Chamaesipho tasmanica and Chthamalus antennatus was monitored over a two year period. C. polymerus and C. tasmanica show a clearly defined breeding season spanning late autumn, winter and early spring. C. antennatus breeds more continuously throughout the year, with a decline in breeding during the winter. The larval stages of C. polymerus, C. tasmanica and C. antennatus are described from larvae reared in the laboratory. Morphological differences allow each larval stage of the three species to be distinguished without difficulty. Unique larval features permit identification to superfamily, family and genus. The similarities of chthamaloid nauplii to those of lepadomorphs and verrucomorphs and their differences from the nauplii of other balanomorphs are discussed. Larval evidence supports the view that the chthamaloids are related more closely than other balanomorphs to the lepadomorphs, and that the coronuloids and balanoids share a comon derivation from the chthamaloids.     

Characterization of Rat ARPP-21 mRNA: Sequence Analysis, Tissue Distribution, and Regulation

ARPP-21 (cyclic AMP-regulated phosphoprotein; Mr = 21,000) is a cytosolic neuronal phosphoprotein that is highly enriched in the striatum and in other dopaminoceptive regions of the brain. The state of phosphorylation of ARPP-21 is also regulated by vasoactive intestinal peptide in intact cells. We previously reported the sequence analysis of bovine ARPP-21 cDNA and have now characterized rat ARPP-21 cDNA to study further the molecular biology of this protein. The sequence of the coding region is 82 and 85% identical at the nucleotide and amino acid levels, respectively, between the two species. There are two major classes of clones, differing only in the lengths of their 3' untranslated ends, suggesting that the different ARPP-21 mRNAs are derived from the use of alternate polyadenylation sites. Both major mRNA species, 2.6 and 0.7 kb, are present at the highest concentration in the striatum, followed by the cortex, consistent with previous immunocytochemical results. Southern blot analysis reveals a simple hybridization pattern, consistent with the presence of a single rat gene encoding ARPP-21. The steady-state levels of the ARPP-21 mRNAs are developmentally regulated but, in the neonatal and mature animal, are not altered following 6-hydroxydopamine lesions of the substantia nigra or by pharmacologic treatments that up-regulate the D1- or D2-dopamine receptors.     

The potential ecological costs and cobenefits of REDD: a critical review and case study from the Amazon region

The United Nations climate treaty may soon include a mechanism for compensating tropical nations that succeed in reducing carbon emissions from deforestation and forest degradation, source of nearly one fifth of global carbon emissions. We review the potential for this mechanism [reducing emissions from deforestation and degradation (REDD)] to provoke ecological damages and promote ecological cobenefits. Nations could potentially participate in REDD by slowing clear‐cutting of mature tropical forest, slowing or decreasing the impact of selective logging, promoting forest regeneration and restoration, and expanding tree plantations. REDD could also foster efforts to reduce the incidence of forest fire. Potential ecological costs include the accelerated loss (through displaced agricultural expansion) of low‐biomass, high‐conservation‐value ecosystems, and substitution of low‐biomass vegetation by monoculture tree plantations. These costs could be avoided through measures that protect low‐biomass native ecosystems. Substantial ecological cobenefits should be conferred under most circumstances, and include the maintenance or restoration of (1) watershed functions, (2) local and regional climate regimes, (3) soils and biogeochemical processes, (4) water quality and aquatic habitat, and (5) terrestrial habitat. Some tools already being developed to monitor, report and verify (MRV) carbon emissions performance can also be used to measure other elements of ecosystem function, making development of MRV systems for ecological cobenefits a concrete possibility. Analysis of possible REDD program interventions in a large‐scale Amazon landscape indicates that even modest flows of forest carbon funding can provide substantial cobenefits for aquatic ecosystems, but that the functional integrity of the landscape's myriad small watersheds would be best protected under a more even spatial distribution of forests. Because of its focus on an ecosystem service with global benefits, REDD could access a large pool of global stakeholders willing to pay to maintain carbon in forests, thereby providing a potential cascade of ecosystem services to local stakeholders who would otherwise be unable to afford them.     

The distribution, density and growth of the European eel, Anguilla anguilla, in the freshwater catchment of the River Thames

Improvements in water quality in the Thames Estuary since the 1960s have removed a barrier to fish migration into the Thames catchment. The extent of recolonization by the eel is examined, using data from 235 electrofished and fyke-netted sites, compared with information on pre-pollution distribution. Density is highest in the lower parts of the catchment and decreases significantly with increasing distance from the tidal limit. Only sparse populations are found beyond 50 km from the tidal limit and are characterized by an increasing bias towards larger, slower-growing females. Artificial stocking is believed to be a significant factor in certain areas. The rate of recolonization has been slow and neither the annual natural recruitment nor distribution of the pre-pollution stock of the 1800s appears to have been achieved. The future management of the stock in relation to its commercial scientific and conservation value is considered.     

Increased CYFRA 21-1, CEA and NSE are Prognostic of Poor Outcome for Locally Advanced Squamous Cell Carcinoma in Lung: A Nomogram and Recursive Partitioning Risk Stratification Analysis

OBJECTIVES: This study aimed to: (1) assess the prognostic significance of serum tumor markers in locally advanced squamous cell carcinoma in lung (LA-SCCL); (2) generate a nomogram to predict the overall survival (OS) and (3) identify a prognostic stratification to assist the therapeutic decision-making. METHODS: LA-SCCL patients receiving definitive radiotherapy and baseline tumor marker measurement were eligible for this retrospective study. Cox proportional hazards regression was used to determine independent factors associated with various survival indexes and a nomogram was created to estimate the 5-year OS probability for individual patient. The identified prognostic factors were recruited into a recursive partitioning analysis (RPA) for OS to stratify patients with distinct outcome. RESULTS: A total of 224 patients were eligible for analysis. Increased cytokeratin-19 fragment (CYFRA 21-1) was independently associated with inferior OS, progression free survival (PFS) and a borderline decreased local-regional progression free survival (LRPFS). Elevated carcino-embryonic antigen (CEA) served as an unfavorable determinant for OS and increased neuron-specific enolase (NSE) was predictive of poor distant metastasis free survival (DMFS). A nomogram integrating KPS, TNM stage, CEA and CYFRA 21-1 was created, resulting in a c-index of 0.62. RPA identified 4 prognostic classifications, with median OS of 27.6, 19.9, 17.3 and 10.9?months for low, intermediate, high and very-high risk groups, respectively. CONCLUSIONS: Baseline tumor marker panel including CYFRA 21-1, CEA and NSE can be prognostic of outcome for LA-SCCL receiving definitive radiotherapy. The RPA identified four prognostic subgroups, which could assist personalized therapy and clinical trial design in LA-SCCL.