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Among sarcomas with a round-cell morphology that lack rearrangement of the EWSR1 gene, rearrangements involving the CIC gene are the most common. In comparison with Ewing Sarcoma, CIC-rearranged sarcomas present at an older average age, arise almost exclusively in soft tissues, are clinically more aggressive, and are more likely to be resistant to the chemotherapy regimens used for Ewing sarcoma. CIC-rearranged sarcomas present more commonly in a deep location, and we suspect that superficial presentations may be under-recognized. In this case series, we report three of such cases. Overall, the morphology is similar to CIC-rearranged sarcomas of deeper locations. We hope to raise awareness among the dermatopathology community by expanding the differential of superficial tumors with round cell morphology.

Diffusion MRI has the potential to provide important information about the connectivity and microstructure of the human brain during normal and abnormal development, non-invasively and in vivo. Recent developments in MRI hardware and reconstruction methods now permit the acquisition of large amounts of data within relatively short scan times. This makes it possible to acquire more informative multi-shell data, with diffusion-sensitisation applied along many directions over multiple b-value shells. Such schemes are characterised by the number of shells acquired, and the specific b-value and number of directions sampled for each shell. However, there is currently no clear consensus as to how to optimise these parameters. In this work, we propose a means of optimising multi-shell acquisition schemes by estimating the information content of the diffusion MRI signal, and optimising the acquisition parameters for sensitivity to the observed effects, in a manner agnostic to any particular diffusion analysis method that might subsequently be applied to the data. This method was used to design the acquisition scheme for the neonatal diffusion MRI sequence used in the developing Human Connectome Project, which aims to acquire high quality data and make it freely available to the research community. The final protocol selected by the algorithm, and currently in use within the dHCP, consists of b = 0, 400, 1000, 2600 s/mm2 with 20, 64, 88 & 128 DW directions per shell respectively.HighlightsA data driven method is presented to design multi-shell diffusion MRI acquisition schemes (b-values and no. directions).This method optimises the multi-shell scheme for maximum sensitivity to the information content in the signal.When applied in neonates, the data suggest that a b=0 + 3 shell strategy is appropriate

Spontaneous release of neurotransmitters is regulated by extracellular [Ca2+ ] and intracellular [Ca2+ ]. Curiously, some of the mechanisms of Ca2+ signaling at central synapses are different at excitatory and inhibitory synapses. While the stochastic activity of voltage-activated Ca2+ channels triggers a majority of spontaneous release at inhibitory synapses, this is not the case at excitatory nerve terminals. Ca2+ release from intracellular stores regulates spontaneous release at excitatory and inhibitory terminals, as do agonists of the Ca2+ -sensing receptor. Molecular machinery triggering spontaneous vesicle fusion may differ from that underlying evoked release and may be one of the sources of heterogeneity in release mechanisms.

Soft tissue sarcomas are rare malignant heterogenous tumors of mesenchymal origin with over fifty subtypes. The use of hematoxylin and eosin stained sections (and immunohistochemistry) in the morphologic assessment of these tumors has been the bane of clinical diagnosis until recently. The last decade has witnessed considerable progress in the understanding and application of molecular techniques in refining the current understanding of soft tissue sarcomas and gastrointestinal stromal tumors beyond the limits of traditional approaches. Indeed, the identification of reciprocal chromosomal translocations and fusion genes in some subsets of sarcomas with potential implications in the pathogenesis, diagnosis and treatment has been revolutionary. The era of molecular targeted therapy presents a platform that continues to drive biomarker discovery and personalized medicine in soft tissue sarcomas and gastrointestinal stromal tumors. In this review, we highlight how the different molecular techniques have enhanced the diagnosis of these tumors with prognostic and therapeutic implications. J. Surg. Oncol. 2015 111:520–531. © 2015 Wiley Periodicals, Inc.

Like many Eastern U.S. salt marshes, East Harbor salt marsh lagoon on Cape Cod was isolated from tidal flow in the 1800s, resulting in near-freshwater conditions and loss of native salt marsh species. After its partial restoration in 2002, a variety of marine and estuarine fauna recolonized East Harbor, and soft shell clam (Mya arenaria) recolonization was particularly prolific. The goal of our study was to evaluate molluscan community composition, density, and distribution at regular intervals for 10 years following restoration, and to relate molluscan community recovery to various physical properties at the site. In 2007, 2008, and 2011, we sampled mollusks at several points across East Harbor, and we also recorded water salinity and temperature, particle size distribution, and submerged aquatic vegetation density. In 2007 and 2008, we encountered 12 and 11 mollusk species, respectively; M. arenaria was the most abundant species in 2007 and the second most abundant species in 2008. In 2011, we encountered eight mollusk species and M. arenaria was the most abundant species. Mollusk species richness declined from 12 to 8 species between 2008 and 2011. Our results show that mollusk species richness and density have declined significantly since the first few years following restoration; related studies attribute this to high summer water temperatures in the Main Lagoon and severe macroalgal blooms during 2005–2006. This suggests that East Harbor is still equilibrating to baseline conditions and that full tidal restoration may be necessary to sustain a diverse mollusk community at East Harbor.

We analyzed land‐cover and forest vegetation data from nearly 25,000 permanent plots distributed across 50 national parks in the eastern United States, along with the matrix around each park, to examine structural characteristics of park forests in relation to their surrounding landscape. Over 2000 of these plots are part of the National Park Service (NPS) Inventory and Monitoring Program (I&M), and the remaining 22,500+ plots are part of the US Forest Service (USFS) Forest Inventory and Analysis (FIA) Program. This is the first study to compare forest structure in protected lands with the surrounding forest matrix over such a large area of the United States and is only possible because of the 10+ years of data that are now publicly available from USFS‐FIA and NPS I&M. Results of this study indicate that park forests, where logging is largely prohibited, preserve areas of regionally significant older forest habitat. Park forests consistently had greater proportions of late‐successional forest, greater live tree basal area, greater densities of live and dead large trees, and considerably larger volume of coarse woody debris. Park forests also had lower tree growth and mortality rates than matrix forests, suggesting different forest dynamics between park and matrix forests. The divergent patterns we observed between matrix and park forests were similar to those reported in studies that compared managed and old‐growth forests, although the differences in our study were less pronounced. With the majority of park forests in second growth, eastern parks may be a more realistic baseline to compare with the more intensively managed matrix forests. We recommend that park managers allow natural disturbance and the development of older structure to continue in park forests. In addition, long‐term maintenance of regional biodiversity will likely require increases in older forest structure in the matrix. As the NPS moves into its next century of land preservation, we encourage managers to consider parks important components of a larger regional effort to preserve biodiversity and ecosystem processes in eastern US forests. The data collected by NPS I&M programs will continue to provide important information and guidance toward these regional conservation efforts.

Functional brain imaging studies have shown abnormal neural activity in individuals recovered from anorexia nervosa (AN) during both cognitive and emotional task paradigms. It has been suggested that this abnormal activity which persists into recovery might underpin the neurobiology of the disorder and constitute a neural biomarker for AN. However, no study to date has assessed functional changes in neural networks in the absence of task-induced activity in those recovered from AN. Therefore, the aim of this study was to investigate whole brain resting state functional connectivity in nonmedicated women recovered from anorexia nervosa. Functional magnetic resonance imaging scans were obtained from 16 nonmedicated participants recovered from anorexia nervosa and 15 healthy control participants. Independent component analysis revealed functionally relevant resting state networks. Dual regression analysis revealed increased temporal correlation (coherence) in the default mode network (DMN) which is thought to be involved in self-referential processing. Specifically, compared to healthy control participants the recovered anorexia nervosa participants showed increased temporal coherence between the DMN and the precuneus and the dorsolateral prefrontal cortex/inferior frontal gyrus. The findings support the view that dysfunction in resting state functional connectivity in regions involved in self-referential processing and cognitive control might be a vulnerability marker for the development of anorexia nervosa.

The effects of bioturbation by the mud fiddler crab (Uca pugnax) on salt marsh seedling recruitment were investigated experimentally in this study. Burrowing and foraging activity caused a large amount of soil disturbance, which in turn negatively impacted the establishment of seedlings. Either seeds did not germinate or seedlings were uprooted or buried. Although the majority of the published literature suggests a positive influence of Uca spp. on salt marsh plant growth, at high densities they have the potential to hinder the re-colonization of areas made bare by previous disturbance. This study illustrates the perhaps underappreciated role that bioturbators can have on vegetation patterns in salt marshes and other ecosystems.

The signal profile measured in balanced steady-state free precession has been shown to exhibit tissue-dependent asymmetries that were hypothesized to relate to properties of the tissue microenvironment. It was proposed that balanced steady-state free precession asymmetry may reflect subtle features of the frequency distribution in tissue. The present work investigates the large balanced steady-state free precession asymmetries observed in white matter. First, maps quantifying the asymmetry are presented, which demonstrate considerable heterogeneity within white matter, with some tracts exhibiting significant asymmetry and others having a nearly symmetric profile. These maps are compared with a diffusion-tensor atlas and indicate that the highest asymmetry is found in tracts oriented perpendicular to the main magnetic field. Measurements conducted at multiple repetition times suggest that the asymmetries are characterized by relatively small frequency shifts. These results are discussed in the context of previous work studying gradientrecalled echo (GRE) signal behavior in white matter, and it is suggested that these two techniques are detecting closely related phenomena. Magn Reson Med 63:396–406, 2010. © 2010 Wiley-Liss, Inc.

Hydrologic restoration of Hatches Harbor, a tide-restricted marsh on Cape Cod (Massachusetts), has resulted in significant plant community changes 7 years following the reintroduction of seawater. Since 1999, incremental increases in flow through a tide-restricting dike have facilitated the rapid decline of salt-intolerant vegetation, while encouraging the expansion of native salt marsh taxa. These changes show strong spatial gradients and are correlated with marsh surface elevation, distance from the point of seawater entry, and porewater salinity. Common reed (Phragmites australis) has not decreased in abundance but has migrated a considerable distance upslope. In the wake of this retreat native halophytes have proliferated. Now that maximum flow through the existing dike structure has been reached, continued recovery may be limited less by changing physicochemical conditions and more by rates of growth, seed dispersal, and seed germination of salt marsh taxa.

We performed a prospective multi-centre study using functional magnetic resonance imaging (fMRI) to better characterize the relationships between clinical expression and brain function in patients with multiple sclerosis (MS) at eight European sites (56 MS patients and 60 age-matched, healthy controls). Patients showed greater task-related activation bilaterally in brain regions including the pre- and post-central, inferior and superior frontal, cingulate and superior temporal gyri and insula (P < 0.05, all statistics corrected for multiple comparisons). Both patients and healthy controls showed greater brain activation with increasing age in the ipsilateral pre-central and inferior frontal gyri (P < 0.05). Patients, but not controls, showed greater brain activation in the anterior cingulate gyrus and the bilateral ventral striatum (P < 0.05) with less hand dexterity. An interaction between functional activation changes in MS and age was found. This large fMRI study over a broadly selected MS patient population confirms that movement for patients demands significantly greater cognitive 'resource allocation' and suggests age-related differences in brain responses to the disease. These observations add to evidence that brain functional responses (including potentially adaptive brain plasticity) contribute to modulation of clinical expression of MS pathology and demonstrate the feasibility of a multi-site functional MRI study of MS.

Objective: To investigate whether plasma omega-3 fatty acid (FA) concentrations (eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) modify the treatment effect of homocysteine-lowering B vitamins on brain atrophy rates and cognitive decline in a placebo-controlled trial. Design: The effect of high-dose B vitamins in the previously reported VITACOG trial [PLoS ONE 5(9) 2010: e12244] was analysed according to baseline omega-3 FA concentrations. This study included 168 elderly (蠅70 y) with Mild Cognitive Impairment randomly assigned either to placebo, or to B vitamins. Results: There was a significant interaction (P = 0.024) between B vitamin treatment and plasma combined omega-3 FA (EPA+DHA) on brain atrophy rates. In subjects with high baseline omega-3 FA (˃590 μmol/L), B-vitamin treatment slowed the mean atrophy rate by 40% compared with placebo (P = 0.023). B-vitamin treatment had no significant effect on rate of atrophy among subjects with low baseline omega-3 FA (

Apolipoprotein E (APOE)-epsilon4 has been associated with an unfavorable course of multiple sclerosis (MS). The mechanisms responsible for this are unclear, although cross-sectional MRI demonstrated a higher extent of "black holes" (BHs) in such patients. Here, we have studied the impact of the APOE genotype on both the longitudinal evolution of focal (BH ratio) and global (brain volume change [BVC]) brain tissue damage. Ninety-nine MS patients underwent ApoE genotyping, clinical examination, and magnetic resonance imaging at baseline and after 2.7 +/- 1.1 years to assess lesion load (LL) and BVC. In APOE-epsilon4 patients, the annual reduction in brain volume was fivefold higher (-0.65 +/- 0.61%) than in those without APOE-epsilon4 (-0.13 +/- 0.36%; p = 0.0001). At baseline, T(2) LL and T(1) LL were non-significantly higher in epsilon4 carriers, despite a shorter disease duration and absence of significant clinical differences. During follow-up, T(1) LL increased from 1.2 +/- 2.3 ccm to 1.7 +/- 2.7 ccm in the epsilon4 group, although T(2) LL did not change, leading to a significantly higher increase in the BH ratio [(T(1) LL/T(2) LL) x 100] from 5.5 to 12.4% (p = 0.005). BH ratio remained almost constant in non-epsilon4 patients (5.0 vs 5.7%). Accelerated brain tissue loss and a higher proportion of lesions evolving into BH therefore provide magnetic resonance imaging evidence for more pronounced tissue destruction in MS patients with APOE-epsilon4.

The Rotenberger Wildlife Management Area (RWMA) is a northern Everglades marsh, in Florida, U.S.A., that will undergo hydrologic restoration to remedy an artificially shortened hydroperiod. In an effort to predict vegetation responses to the impending changes in hydrology, plant community development from the resident seed bank was observed in response to three different moisture regimes in March and September 1998. Percent cover, species densities, total seedling densities, and percentages of facultative, facultative-upland, and upland indicator species were significantly higher in moist than in saturated soils. Flooding inhibited the germination of all species except Typha domingensis (cattail), which emerged in the highest numbers from saturated soils in both assays. Lythrum alatum (purple loosestrife) was abundant in both saturated and moist conditions. The season of assay affected species densities and the communities. Percent facultative-wetland species increased in saturated soils in the March assay but not in September. In contrast, percent obligate hydrophytes were higher in saturated conditions only in the September assay. In general the assay communities bore little resemblance to vegetation in currently undisturbed or historic wetlands of the northern Everglades. Consequently the RWMA seed bank will contribute little to the development of a restored community. Moreover, rehydration may encourage the spread of undesirable hydrophytes such as T. domingensis. This study supports the contention that hydrologic restoration must be accompanied by some level of active vegetation management and that the reference condition cannot be attained passively.

Three experiments examined the role of individual differences in combination with contextual factors hypothesized to moderate the level of hostility toward females evident in male participants' responses. In Study I, we manipulated survey context and examined the influence of participants' levels of rape myth acceptance (RMA) on self-reported rape likelihood. In Study 2, we examined the interactive role of target gender and participants' levels of sex guilt (SG) on aggression toward the target after exposure to an erotic film. Study 3 results suggested that high SG males have particularly negative responses to women (but not men) who enjoy erotic presentations, consistent with a “Jack-the-Ripper” interpretation of the Study 2 findings.

Cystic fibrosis (CF) is associated with significant morbidity and mortality, despite significant advances in conventional treatment. The field of gene therapy has progressed rapidly since the cystic fibrosis transmembrane conductance regulator (CFTR) gene was cloned. In this review we discuss current knowledge on the underlying molecular defect in CF, and the progress in gene transfer studies from the early in vitro work through to clinical trials, including the development of endpoints to assess efficacy. We highlight the problems encountered, and likely future directions of the field.

Many neurons of the central and peripheral nervous systems display multiple high voltage-activated (HVA) Ca2+ currents, often classified as L-, N-, P-, Q, and R-type. The heterogeneous properties of these channels have been attributed to diversity in their pore-forming alpha 1, subunits, in association with various beta subunits. However, there are large gaps in understanding how individual subunits contribute to Ca2+ channel diversity. Here we describe experiments to investigate the roles of alpha 1E and beta 3 subunits in mammalian neurons. The alpha 1E subunit is the leading candidate to account for the R-type channel, the least understood of the various types of high voltage-activated Ca2+ channels. Incubation with alpha 1E antisense oligonucleotide caused a 53% decrease in the peak R-type current density, while no significant changes in the current expression were seen in sense oligonucleotide-treated cells. The specificity of the alpha 1E antisense oligonucleotides was supported by the lack of change in the amplitude of P/Q current. These results upheld the hypothesis that members of the E class of alpha 1 subunits support the high voltage-activated R-type current in cerebellar granule cells. We studied the role of the Ca2+ channel beta 3 subunit using a gene targeting strategy. In sympathetic beta 3-/- neurons, the L-type current was significantly reduced relative to wild type (wt). In addition, N-type Ca2+ channels made up a smaller proportion of the total Ca2+ current than in wt due to a lower N-type current density in a group of neurons with small total currents. Voltage-dependent activation of P/Q-type Ca2+ channels was described by two Boltzmann components with different voltage dependence. The absence of the beta 3 subunit was associated with a shift in the more depolarized component of the activation along the voltage axis toward more negative potentials. The overall conclusion is that deletion of the beta 3 subunit affects at least three distinct types of HVA Ca2+ channel, but no single type of channel is solely dependent on beta 3.

We used a Beverton–Holt equilibrium yield model to predict the effects of four different length limits (203, 229, 254, and 279 mm) on harvest of black crappies Pomoxis nigromaculatus and white crappies P. annularis in Weiss Lake, Alabama. The current 254-mm length limit took effect in 1990, and we wanted to assess length limits with more recent data. We documented angler harvest and catch rates before and after the initiation of the size limit. Size structure, growth, and total mortality were estimated for fish collected with trap nets and by electrofishing. Growth was above average compared with other reservoirs in the state with fish reaching 254 mm in about 2.4 years. Estimates of total annual mortality ranged from 51% to 64% and annual exploitation was 33%, but because of uncertainty, a wide range of fishing and natural mortality rates were incorporated into the simulations. Three years after the length limit took effect, angler harvest and catch of crappies increased two–four fold and the si...

In a prior report, we described the isolation and characterization of SIVrcm, a distinct primate lentivirus found in a household pet Red-Capped Mangabey (RCM) in Gabon. SIVrcm is divergent from HIV-1 and HIV-2/SIV families of primate lentiviruses. In this report, additional in vitro replication studies and the results of SIVrcm infection in macaques are presented. SIVrcm causes little cytopathic effedct in Molt 4 Clone 8 cells and in rhesus and human PBMCs. In vivo, SIVrcm is non-pathogenic after 200 days in rhesus macaques and after one year in cynomolgous macaques, but does cause a chronic infection in both macaques.

Two experiments tested the hypothesis that framing biases in decision making would affect more strongly individuals with relatively low levels of need for cognition (NC). Participants were classified as high or low NC based on responses to a standard scale and subsequently were exposed to one of two framings of a choice problem. Different choice problems were used in each experiment, modeled after those developed by Kahneman and Tversky. Experiment 1 employed a monetary task and Experiment 2 a medical decision-making task. Consistent with expectations, framing effects on choice were observed in both experiments, but only for low NC participants. High NC participants were unaffected by problem framing, showing that they were less susceptible to attempts to alter their frame of reference.

The ‘traditional’ view, in both educational and labour-market policy, of the transition from education to employment centres on the school-leaving decision — in other words, on a particular point in time when the individual concerned decides to leave full-time education and enter the labour market. The pattern and timing of school-leaving decisions have given cause for considerable concern amongst policymakers in the UK. Many more individuals leave full-time education prematurely in the UK than in other industrialised (and some industrialising) countries, and there has been considerable discussion of the role that may be played by financial factors in early school leaving (for example, Micklewright, Pearson and Smith (1988 and 1990)). In response to these concerns, educational and social security policies have sought to discourage early entry into the labour market, whilst labour-market policies directed at the 16- to 18-year-old age-group have concentrated on providing training and work experience to those who have taken the decision to leave school.

Recent attempts to improve the influence of social marketing have often focused on behavioral strategies, largely neglecting the concept of attitude. This is understandable given the weak performance of attitudinal variahles as a predictor in past studies of proenvironmental hehavior. However, we suggest that part of the reason for the poor association hetween attitudes and such hehavior is the possibility that many altruistic acts such as recycling are suhject to affective influences that may not he fully captured by commonly employed attitude measures. We also suggest that attitude strength might moderate the extent to which affective reactions account for additional variance in hehavior. Specifically, it is predicted that affect is more important for weak than for strong attitudes. Empirical results are presented to support these suggestions. © 1994 John Wiley & Sons, Inc.

Over the past three years, policy towards the taxation of energy has been debated vigorously. In 1991 the European Commission proposed a new carbon/energy tax as part of a package of measures intended to reduce energy use and to help the Community meet international targets for reducing emissions of carbon dioxide and other $lsquo;greenhouse gases’. This would have applied to both domestic and industrial users of energy and motor fuels. Also, in the area of UK domestic policy, the Chancellor’s 1993 Budget announced the phased extension of the standard rate of value added tax to domestic energy, which had hitherto been zero-rated in the UK. The extension of standard-rate VAT to domestic energy was primarily motivated by the need for increased tax revenues, but, at the same time, the Government maintained that the measure would have the valuable byproduct of reducing energy consumption, and hence contributing to achievement of targets for reducing greenhouse gas emissions.

Starch-gel electrophoretic analysis of 1,081 crappies collected from October 1990 through November 1991 revealed that black crappie Pomoxis nigromaculatus and white crappie P. annularis were hybridizing in Weiss Lake, Alabama. Crappie hybrids made up 22% of the population and were found in the 1988 to 1991 year-classes. First-generation (F1) hybrids were seven times more abundant than second-generation and higher (F x ) hybrids. The F1 hybrids expressed superior growth and survival, and they recruited into the fishery (254-mm total length minimum size limit) earlier than the parental species. Distributions of alleles among F x hybrids indicated that F1 hybrids were more likely to successfully mate and produce offspring with black crappies than with white crappies. Factors that may have contributed to hybridization between crappie species include failure to identify specific mates due to low water clarity during spring when these fish spawn, short and overlapping spawning times, and fluctuating wa...

The studies presented in this paper examined empathy, especially perspective taking, as a potential inhibitor of interpersonal aggression. The theoretical rationale for these investigations derived from Zillmann's [(1988): Aggressive Behavior 14: 51–64] cognitive excitation model. Study 1 revealed that dispositional empathy correlates negatively with self-reported aggression and with conflict responses that reflect little concern for the needs of the other party. Empathy also was positively related to constructive responses to interpersonal conflict (i. e., those that do involve concern for the needs of the other party). In Study 2, perspective taking was manipulated with instructions to subjects prior to participation in a reaction-time task designed to measure aggression. When threat was relatively low, subjects who were instructed to take the perspective of the target responded less aggressively than did those who had been instructed to focus on the task. Study 3 examined the effect of dispositional perspective taking on verbal aggression. Threat was manipulated in terms of the combination of provocation and gender of the interactants. As predicted, perspective taking related to aggression inhibition under conditions of moderate threat–for males under low provocation and females under high provocation. These effects were predicted and explained in the context of the cognitive-excitation model. © 1994 Wiley-Liss, Inc.

The reaction of ketoketene dimers with organolithium reagents afforded 1,3-diketones in good to excellent yields, and with good diastereoselectivity in some cases.

Environmental problems now figure prominently on the policy agenda in both london and Brussels. The recent Environment White Paper, This Common Inheritance, has signalled the British Government's intention that policy in a wide range of areas should reflect environmental concerns, and both Britain and the European Community have been active participants in international negotiations on cross-country and global environmental problems.

Male Hybomitra illota (Osten Sacken) were found aggregating in clearings in wooded areas in Rondeau Provincial Park, Ontario, Canada. At these sites they perched on a variety of substrates, and made frequent flights in pursuit of insects flying overhead. We know that these pursuit flights were part of the mating behaviour because some pursuits of female H.illota resulted in copulation. We call the aggregation sites ‘mating arenas’ and the behaviour exhibited by males ’perch-and-pursuer’. Aggregation occurred only on sunny days, when ambient temperatures exceeded 18oC. Males perched in sunny areas, except during hot afternoons, when some males were found in dappled shade. Some marked males remained at or returned to sites for up to 13 days, but most males did not remain at the same area within a site, even during the same day. The contents of the oesophageal diverticula of males were depleted daily. Concentration of diverticular carbohydrates changed through the season. Thoracic temperatures of males were high (c. 37oC) and were regulated, probably both behaviourally and physiologically. The sites and behaviour of male H. illota at aggregation arenas bear some resemblance to lek sites and lekking in vertebrates. Males are aggregated in an arena but, within the perching component of the behaviour, we saw no evidence of male territoriality, display, or female choice. However, competition, display, or mate choice could occur within the pursuit-flight component.

A new powerful tris(2,2′-bipyridyl) chelating ligand, 1,4,7-tris(2,2′-bipyridyl-5-ylmethyl)1,4,7-triazacyclononane (L1), has been synthesised and characterised, and an X-ray structure of [Ru(L1H)]3+ obtained; in the complex all three bipyridyl groups are coordinated, with a fairly regular octahedral RuII geometry, and although the azamacrocyclic nitrogen-atoms are non-coordinating to RuII, in aqueous solution they trap a single proton in the cavity between the macrocycle and the RuII, and which cannot be removed even at high pH.

In much ecological hypothesis testing, Type II errors may be more serious than Type I errors ; ecologists are encouraged to make an a priori assessment of the relative costs of both types of error. Distribution-free statistics such as the Mann-Whitney procedure are not necessarily more powerful nor more robust than their parametric analogues.

1. The chloride (Cl-) currents activated by caesium ions (Cs+), glycine and gamma-aminobutyric acid (GABA) were compared following their application to rat neurones that had been grown in cell culture. Recordings were made using the whole-cell patch clamp technique under voltage clamp conditions. 2. In spinal cord neurones, bicuculline methiodide antagonized GABA-activated currents more effectively than Cs+ - or glycine-activated currents. However, strychnine was more effective at blocking the currents activated by Cs+ or glycine than those activated by GABA. 3. Of the 3 agonists, only GABA activated currents in cells from the intermediate lobe of the rat pituitary. 4. In spinal neurones the size of the currents activated by 70 mM Cs+ was correlated to the size of the currents activated by 15 microM glycine (P less than 0.005; n = 10, Spearman's rank correlation), but there, was no significant correlation between the size of the currents activated by these agents and 10 microM GABA. 5. The joint application of glycine and Cs+ activated currents that were approximately twice as big as the sums of the currents activated by separate applications of the same doses. This synergism was consistent with Cs+ acting at the same receptor as glycine (7 microM glycine being equivalent to 31 +/- 7 mM Cs+). 6. It was concluded that Cs+ activates the same Cl- channel as the inhibitory neurotransmitter glycine.

Male and female Tabanus sackeni Fairchild (Diptera: Tab-anidae) were collected on a road, dipping at pools of water on a road, and at uv-light traps; females were also caught in Malaise traps. Most males at uv-light traps were collected just before sunrise. Most females at uv-light traps were collected in the evening and most had recently taken a blood-meal. Malaise-trapped females showed a distinct crepuscular peak of host-seeking activity. Crop volumes were variable in these host-seeking females; many had large crops. Crop volumes were small in individuals of both sexes collected dipping or on the road. Many dipping females were gravid. By examining how physiological states and the behaviour of individuals changed according to trap type, we are able to make inferences about the timing and importance of a number of unobserved activities. A link between uptake of water and sugar feeding was apparent and we postulate that mating takes place in the early morning, just before sunrise.

The structure of the ionic hydrogen-bonded adduct of the s-propyl cation and water, and of protonated propan-2-ol, have been determined at the 3-21G and 6-31G* levels. The relative energies of these species have been determined with the inclusion of electron correlation effects. The predicted greater stability of protonated propan-2-ol is in line with collisional activation mass spectrometric studies of Holmes et al.

PUMPTEST.BAS is a BASIC program for IBM PCb microcomputers and compatibles that calculates transmissivity and storativity of confined aquifers using the Cooper-Jacob method.