Feeding studies on Onychiurus arcticus (Tullberg) (Collembola: Onychiuridae) on West Spitsbergen

The feeding biology of the arctic collembolan Onychiurus arcticus (Tullberg) is described from West Spitsbergen, based on a combination of gut content analyses for field collected and microcosm-living animals, together with laboratory feeding trials. There was wide variation in the food items consumed by individual animals, reflecting the wide choice available in the environment. Most animals fed predominantly on living and dead bryophytes, detritus and to a lesser extent algal cells. Laboratory trials showed that O. arcticus feeds as a herbivore on a range of bryophyte species. The presence of dense aggregations below bird cliffs and elsewhere may reflect the distribution of particularly favourable microenvironments.     

Aspergillosis: Mechanisms of pathogenicity implicated and approach to laboratory diagnosis.

Aspergillosis comprises a wide range of clinical conditions, of which the most serious is invasive aspergillosis, which particularly affects immunodeficient individuals. In the present work we present a review centred on three main aspects of this disease: 1) Possibility of differentiation of strains of Aspergillus fumigatus by phenotyphic and genotypic methods, 2) Mechanisms of pathogenicity of this species and especially the relationships of elastase activity, and 3) Laboratory diagnosis of aspergillosis, principaly in terms of determination of circulating antigens and DNA sequences in the blood and urine of patients.     

Avoiding false positive HIV results on life assurance proposers: the necessity for follow-up

The serological reaction to HIV infection is almost invariably a dynamic progression towards strong reactivity to a wide range of viral antigens. Serological diagnosis should therefore be based either on the presence of this wide range in a single specimen or on the demonstration of increasing activity between two specimens collected at an interval of two or more weeks and tested in parallel. When a specimen is reactive a second should in any case be collected to check the identity of the first. These precepts are sometimes being ignored, especially in non-clinical testing, e.g., for purpose of life assurance. Two recent cases in which there were false but unchanging enzyme immunoassay and Western blot reactions that might have been interpreted as positive illustrate the potential for error.     

Germination responses of Spartidium saharae (Coss. & Dur.) Pomel (Fabaceae) to temperature and salinity

Spartidium saharae is an endemic species of the Saharo-Arabian region. It is a tall shrub widely distributed in many sandy habitats including desert dunes and sandy systems in south-western part of Tunisia, where water and salinity are serious constraints. Laboratory experiments were carried out to assess temperature and salinity effects on seed germination. The seed germination responses were determined in complete darkness over a wide range of temperatures and salinities. Germination was inhibited by either an increase or decrease in temperature from the optimal temperature range (15–20°C). Highest germination percentages were obtained under nonsaline conditions and an increase in NaCl concentrations progressively inhibited seed germination. An interaction between salinity and temperature yielded no germination at 200 m m NaCl.     

Magnetic labeling, detection, and system integration

Among the plethora of affinity biosensor systems based on biomolecular recognition and labeling assays, magnetic labeling and detection is emerging as a promising new approach. Magnetic labels can be non-invasively detected by a wide range of methods, are physically and chemically stable, relatively inexpensive to produce, and can be easily made biocompatible. Here we provide an overview of the various approaches developed for magnetic labeling and detection as applied to biosensing. We illustrate the challenges to integrating one such approach into a complete sensing system with a more detailed discussion of the compact Bead Array Sensor System developed at the U.S. Naval Research Laboratory, the first system to use magnetic labels and microchip-based detection.     

Relation entre les teneurs en soufre des biominéraux calcaires et leurs caractéristiques minéralogiques

Sulfur concentration measurements in calcareous invertebrate hard-parts covering a wide range of taxa are compared, using relevant statistical tools, to mineralogical and microstructural features of skeletons. In parallel with recent data concerning sulfur characterization in mineralizing matrices, this allows the current concepts regarding early stages and further development of calcareous biominerals to be discussed.     

Competitive assay formats for high-throughput affinity arrays

The authors describe a novel method for the quantitation of differential levels of biomolecules using unlabeled samples and protein-binding arrays for assessing differential expression. Traditional affinity arrays, whether in microplates or protein microarrays, suffer from a few common problems-a shortage of characterized antibodies and highly variable affinities for those available. Also, the assayed proteins could be present in a wide range of concentrations and physicochemical properties, so that it becomes an onerous task to optimize assay conditions for each antibody-antigen pair. Currently, this restricts parallel affinity assays to a low number of carefully selected antibodies and restricts the development of highly multiplexed parallel affinity assays. A displacement strategy allows the use of a much wider range of antibodies, reducing the requirement for matched affinities. The competitive assays described here also show a much higher tolerance for nonspecific background noise. The range of assayed protein concentrations is only limited by the sensitivity of the detection system used.     

Microclimate limits thermal behaviour favourable to disease control in a nocturnal amphibian

While epizootics increasingly affect wildlife, it remains poorly understood how the environment shapes most host–pathogen systems. Here, we employ a three‐step framework to study microclimate influence on ectotherm host thermal behaviour, focusing on amphibian chytridiomycosis in fire salamanders (Salamandra salamandra) infected with the fungal pathogen Batrachochytrium salamandrivorans (Bsal). Laboratory trials reveal that innate variation in thermal preference, rather than behavioural fever, can inhibit infection and facilitate salamander recovery under humidity‐saturated conditions. Yet, a 3‐year field study and a mesocosm experiment close to the invasive Bsal range show that microclimate constraints suppress host thermal behaviour favourable to disease control. A final mechanistic model, that estimates range‐wide, year‐round host body temperature relative to microclimate, suggests that these constraints are rule rather than exception. Our results demonstrate how innate host defences against epizootics may remain constrained in the wild, which predisposes to range‐wide disease outbreaks and population declines.     

Parallel, high-throughput purification of recombinant antibodies for in vivo cell assays

We describe a method for high-throughput, parallel purification of secreted proteins to analyse large numbers of protein samples in cell-based assays for the discovery of protein therapeutics. The procedure is generic and capable of 96 parallel purifications and compatible, in both yield and purity, with a wide assay range. By optimising expression and purification steps as well as using novel hardware, in particular a chromatography press capable to purify target proteins from viscous media, we exemplify the process for the generation of single-chain Fv antibody fragments (scFv) and the purification of full-length IgG. The described process can operate robustly with a throughput of over 2,000 samples per month.     

Introduction

Laboratory studies were conducted on the acceptability of various diets to the Australian phytoseiidAmblyseius victoriensis (Womersley) as indicated by effect on development, survival and oviposition. A wide range of sugar, pollen and animal diets were utilised by female predators which prolonged survival over that of unfed predators. However, successful development and oviposition was obtained only with diets consisting of pollen or rust mites as prey. The implications of these findings to the effectiveness ofA. victoriensis as a biological control agent of phytophagous mites are discussed.     

The probability of parallel genetic evolution from standing genetic variation

Parallel evolution is often assumed to result from repeated adaptation to novel, yet ecologically similar, environments. Here, we develop and analyse a mathematical model that predicts the probability of parallel genetic evolution from standing genetic variation as a function of the strength of phenotypic selection and constraints imposed by genetic architecture. Our results show that the probability of parallel genetic evolution increases with the strength of natural selection and effective population size and is particularly likely to occur for genes with large phenotypic effects. Building on these results, we develop a Bayesian framework for estimating the strength of parallel phenotypic selection from genetic data. Using extensive individual‐based simulations, we show that our estimator is robust across a wide range of genetic and evolutionary scenarios and provides a useful tool for rigorously testing the hypothesis that parallel genetic evolution is the result of adaptive evolution. An important result that emerges from our analyses is that existing studies of parallel genetic evolution frequently rely on data that is insufficient for distinguishing between adaptive evolution and neutral evolution driven by random genetic drift. Overcoming this challenge will require sampling more populations and the inclusion of larger numbers of loci.     

Host range testing for risk assessment of a sexually dimorphic polyphagous invader,painted apple moth

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An automated protein annotation filter for integrating web-based annotation tools

A wide range of web based prediction and annotation tools are frequently used for determining protein function from sequence. However, parallel processing of sequences for annotation through web tools is not possible due to several constraints in functional programming for multiple queries. Here, we propose the development of APAF as an automated protein annotation filter to overcome some of these difficulties through an integrated approach.     

Insulin and insulin mixtures; nph insulin

There are several distinct types of commercial insulins available, and with combinations of these many curves of timing of insulin action may be obtained, but none can parallel the action of a normal pancreas.NPH insulin, the newest addition, has a wide range of usefulness and may supplant many of the other types and combinations.     

INSULIN AND INSULIN MIXTURES—NPH Insulin

There are several distinct types of commercial insulins available, and with combinations of these many curves of timing of insulin action may be obtained, but none can parallel the action of a normal pancreas.NPH insulin, the newest addition, has a wide range of usefulness and may supplant many of the other types and combinations.     

Wnt/β-catenin signaling and disease

The WNT signal transduction cascade controls myriad biological phenomena throughout development and adult life of all animals. In parallel, aberrant Wnt signaling underlies a wide range of pathologies in humans. In this Review, we provide an update of the core Wnt/β-catenin signaling pathway, discuss how its various components contribute to disease, and pose outstanding questions to be addressed in the future.     

Effect of discothèque environment on epileptic children.

A free-field study of 22 epileptic children, selected on the basis of past electroencephalographic abnormality, identified a group who exhibited a significant increase in epileptiform discharge rate on electroencephalography in a discothèque environment (p less than 0.05). Laboratory investigations showed that these children were activated by a wide range of stimuli, including intermittent photic stimulation and exercise. The response to exercise was a good predictor of a child''s electroencephalographic response in a discothèque. The findings suggest that most epileptic children are not particularly vulnerable in a discothèque environment.     

The National Climate Laboratory-an Unappreciated Tool for Ecological Research

[First paragraph(s)...]“A freezing chamber offers an easy place for such [frost] experiments... and ... valuable data as to the cold-resisting powers of our plants might be arrived at” (Cockayne, 1897). The National Climate Laboratory was opened in 1970 and has been operating for the past 25 years (recently celebrating its anniversary) for both national and international scientists carrying out environmental research on plants and animals (Halligan, 1995). The facilities have been used by a wide range of plant and animal based researchers from the pastoral, horticultural, and forestry sectors involving a range of disciplines from agronomy, pathology, entomology, physiology, plant breeding and zoology. New Zealand ecologists have been conspicuously absent (in spite of the potential in controlled environment research seen by pioneering ecologists—see above quotation) and yet there has been a range of activities that are complementary to this discipline.     

Development of Reference Procedures for Broth Microdilution Antifungal Susceptibility Testing of Yeasts with Standardized Endpoint Determination

Standard guidelines for the broth microdilution antifungal susceptibility testing of amphotericin B, flucytosine, fluconazole, miconazole and itraconazole are reported. These are a modification of the method developed by the National Committee for Clinical Laboratory Standards (NCCLS) on the following two points: standardization of the means of endpoint determination and the inclusion of miconazole and itraconazole in the testing. MIC was determined to be when the positive control had a turbidity of 0.2 at the 630 nm wavelength. The endpoint was 80% inhibition for azoles and 100% inhibition for other drugs. The method provided good reproducibility, and a wide range of MIC distribution was observed in all antifungal agents except amphotericin B.