Halocynthia papillosa (Linnaeus, 1767) as an indicator of SCUBA diving impact

The solitary ascidian Halocynthia papillosa (Linnaeus, 1767) is proposed as a good indicator of the deleterious effect of SCUBA diving on the Mediterranean coralligenous communities. A comparative survey of H. papillosa populations at frequented and unfrequented localities was carried out over a two-year period (during 2006 and 2007), before and after a peak diving season in the Sierra Helada Marine Park (SW Western Mediterranean Sea). We observed bigger and more abundant individuals of H. papillosa at undived sites than at frequented dived sites during the period of study. Furthermore, individuals of H. papillosa in the most frequented localities occupied more cryptic positions than in the undived localities. H. papillosa was shown to be very sensitive to the adverse effects of SCUBA diving. This species could represent a reliable bioindicator of diving activity and as such constitute a useful tool for the quick and easy monitoring of impact on coralligenous communities before this damage becomes unmitigatable.     

HRP uptake by olfactory and vomeronasal receptor neurons: use as an indicator of incomplete lesions and relevance for non-volatile chemoreception

The transport of HRP (horseradish peroxidase) from the nasalcavity to the brain by intact olfactory receptor axons was usedto investigate the effectiveness of methods commonly used inbehavioral studies for deafferenting nasal chemoreceptor systems.The HRP experiments demonstrated that routine intranasal lavagewith zinc sulfate solution fails to destroy all olfactory receptorneurons in hamsters, in spite of the distinct behavioral deficitthat this treatment can cause in the male hamster. The intracranialdeafferentation of the accessory olfactory bulb by surgicalsection of the vomeronasal nerves was generally effective butthere was much incidental damage to main olfactory nerves thatwould probably not be detected without the HRP tracer. The distribution pattern of HRP molecules introduced into themammalian nasal cavity, as shown by the uptake of HRP by nasalchemoreceptors and its transport to the brain, was also usedto identify potential pathways for non-volatile stimulus moleculeswithin the nose. HRP reaction product was reliably detectedin the glomeruli of the main olfactory bulb after HRP was depositedat the nostril, demonstrating that nonvolatile materials, oncethey have entered the nasal cavity, can reach the main olfactoryreceptor neurons in the posterior nasal epithelium. Significantamounts of HRP reaction product were never observed in the accessoryolfactory bulbunlessa large dose of epinephrine had been givento activate the vomeronasal organ pumping mechanism, which drawssubstances into the vomeronasal organ lumen. Thus, it seemsthat stimulus access to vomeronasal receptor neurons is controlledindependently of access to main olfactory receptor neurons.     

Leaf-shape as an indicator of introgression between Betula pendula and B. pubescens

Summary

Leaf-shape comparisons were made between individual trees in a mixed wood containing B. pendula and B. pubescens, and two relatively pure stands. Data sets were subjected to analysis of variance, principal components and discriminant analyses in order to study within-tree variation, variation within each species and the relationships between them. Within-tree variation was found to be much less than that between trees and principal component analysis provided a separation of the material into species groups and indicated extensive variation within them. The employment of a discriminant function sharpened the separation of the pure woods and pointed to the occurrence of possible hybrids and back-crossed individuals within the mixed wood. The findings indicate that gene flow probably proceeds from the diploid to the tetraploid level.     

Cell aggregation on agar as an indicator for cell-matrix adhesion: effects of opioids

The slow aggregation assay is generally used to study the functionality of cell–cell adhesion complexes. Single cells are seeded on a semisolid agar substrate in a 96-well plate and the cells spontaneously aggregate. We used HEK FLAG-MOP cells that stably overexpress the mu opioid receptor and the mu-opioid-receptor-selective agonists DAMGO and morphine to study whether other factors than functionality of cell–cell adhesions complexes can contribute to changes in the pattern of slow aggregation on agar. HEK FLAG-MOP cells formed small compact aggregates. In the presence of DAMGO and morphine, larger and fewer aggregates were formed in comparison to the vehicle control. These aggregates were localized in the center of the agar surface, whereas in the vehicle control they were dispersed over the substrate. However, in suspension culture on a Gyrotory shaker, no stimulation of aggregation was observed by DAMGO and morphine, showing that opioids do not affect affinity. A dissociation experiment revealed that HEK FLAG-MOP aggregates formed in the absence or presence of opioids are resistant to de-adhesion. We demonstrated that the larger aggregates are neither the result of cell growth stimulation by DAMGO and morphine. Since manipulations of the substrate such as increasing the agar concentration or mixing agar with agarose induced the same changes in the pattern of slow aggregation as treatment with opioids, we suggest that cell–substrate adhesion may be involved in opioid-stimulated aggregation.     

F2-isoprostanes as an indicator and risk factor for coronary heart disease

Coronary heart disease (CHD) is the leading single cause of death in the United States and most Western countries, killing more than 400,000 Americans per year. Although CHD often manifests suddenly as a fatal myocardial infarction, the atherosclerosis that gives rise to the infarction develops gradually and can be markedly slowed or even reversed through pharmacological and lifestyle interventions. These same atherosclerotic processes also drive related vascular diseases such as stroke and peripheral artery disease, and individuals surviving occlusive events often develop additional complications including ischemic cardiomyopathy and heart failure. Therefore, better detection of subclinical atherosclerosis, along with more effective treatments, could significantly reduce the rate of death from CHD and related vascular diseases in the United States. In recent years, oxidation of polyunsaturated fatty acids (PUFAs) in plasma lipoproteins has been postulated to be a critical step in the development of atherosclerosis. If so, then monitoring lipid peroxidation should be a useful indicator of disease risk and progression. This review focuses on the evidence that specific PUFA peroxidation products, the F(2)-isoprostanes, are useful biomarkers that could potentially be utilized as indicators of CHD.     

Multiple antibiotic resistance of heterotrophic bacteria in the littoral zone of Lake Shira as an indicator of human impact on the ecosystem

Resistance to Ampicillin and Kanamycin displayed by heterotrophic bacteria isolated in Summer and in Spring from the littoral and the central parts of Lake Shira (a therapeutic lake in the Khakasia Republic, Russia) has been investigated. It has been found that in Summer, human and animal microflora featuring multiple antibiotic resistance (to Ampicillin and Kanamycin) predominates in all the studied stations of the littoral zone of the lake. In Spring, concentrations of bacteria featuring multiple antibiotic resistance decrease significantly and bacteria sensitive to antibiotics predominate in the lake. Emergence of multiple antibiotic resistance in bacteria of Lake Shira is caused by the input of allochthonous bacteria into the lake; this feature of heterotrophic bacteria of Lake Shira can be used to monitor the impact on the ecosystem made by health resorts.     

Dream intensity profile as an indicator of the hysterical tendencies to dissociation and conversion.

The present study explored the clinical utility of the Dream Intensity Scale (DIS) by evaluating the degree to which the components of dream intensity can serve as indicators of the tendencies to hysterical dissociation and conversion, taking neuroticism and psychological boundaries into consideration. The discriminant models constituted by the DIS scales alone differentiated participants who manifested clinically significant dissociative or conversion symptoms from the remaining sample, with the accuracy rate ranging between 67.2% and 71.5%. The discriminative power of the DIS was so impressive that the inclusion in the models of neuroticism, psychological boundaries, and dissociative or conversion levels—the key factors associated with hysteria—raised the correct classification rate by less than 9%. The relationships between neuroticism, boundary thinness, dissociative features, epileptic-like symptoms, and subjective dream intensity were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Derivation of regional crop sequences as an indicator for potential GMO dispersal on large spatial scales

A methodological approach is presented which aims to visualise the constraints for crop sequence planning in agriculture in a regional, large-scale context. In particular, the relationship between the scope of oilseed rape cultivation and the overall regional cropping structure, the share of particular farm types and the interactions between single crops have been analysed. The identified constraints have been applied to specify current and regionally typical crop sequences as input data for large-scale ex ante assessments, here exemplary for the genome dispersal risk in the case of GM oilseed rape cultivation.The regional and spatio-temporal variation of crop sequences for oilseed rape was analysed and generalised through a combination of analytical, classification and up-scaling techniques. In order to anticipate and assess the dispersal risks of transgenic oilseed rape, the methodology was tuned on crop sequences, which strongly influence the temporal dispersal of genetically modified oilseed rape. The regional cropping patterns for oilseed rape were analysed for the four northernmost German federal states: Schleswig-Holstein, Mecklenburg-Western Pomerania, Lower Saxony and Brandenburg. For typical regional crop clusters, specific crop sequences were derived, taking into account the constraints between crops and the weights for the particular crops as related to farm type. Real land-use data obtained at particular research sites were used to precisely determine the frequency of the single crops, as well as to discover sub-dominant crop combinations, which may have a high impact on dispersal processes. The introduced methodology stresses the following aspects: (i) reflection of the current situation due to links to periodically updated statistical data, (ii) implementation of the relationships and constraints between the different crops through statistical analyses, (iii) transfer of extensive, spatially limited agricultural data and expert knowledge to a large-scale context and (iv) integration of sub-dominant measures that are highly sensitive for particular processes.     

Measuring the extent and effectiveness of protected areas as an indicator for meeting global biodiversity targets

There are now over 100000 protected areas worldwide, covering over 12% of the Earth's land surface. These areas represent one of the most significant human resource use allocations on the planet. The importance of protected areas is reflected in their widely accepted role as an indicator for global targets and environmental assessments. However, measuring the number and extent of protected areas only provides a unidimensional indicator of political commitment to biodiversity conservation. Data on the geographic location and spatial extent of protected areas will not provide information on a key determinant for meeting global biodiversity targets: 'effectiveness' in conserving biodiversity. Although tools are being devised to assess management effectiveness, there is no globally accepted metric. Nevertheless, the numerical, spatial and geographic attributes of protected areas can be further enhanced by investigation of the biodiversity coverage of these protected areas, using species, habitats or biogeographic classifications. This paper reviews the current global extent of protected areas in terms of geopolitical and habitat coverage, and considers their value as a global indicator of conservation action or response. The paper discusses the role of the World Database on Protected Areas and collection and quality control issues, and identifies areas for improvement, including how conservation effectiveness indicators may be included in the database to improve the value of protected areas data as an indicator for meeting global biodiversity targets.     

Brown planthopper (N. lugens Stal) feeding behaviour on rice germplasm as an indicator of resistance

Background

The brown planthopper (BPH) Nilaparvata lugens (Stal) is a serious pest of rice in Asia. Development of novel control strategies can be facilitated by comparison of BPH feeding behaviour on varieties exhibiting natural genetic variation, and then elucidation of the underlying mechanisms of resistance.

Methodology/Principal Findings

BPH feeding behaviour was compared on 12 rice varieties over a 12 h period using the electrical penetration graph (EPG) and honeydew clocks. Seven feeding behaviours (waveforms) were identified and could be classified into two phases. The first phase involved patterns of sieve element location including non penetration (NP), pathway (N1+N2+N3), xylem (N5) [21] and two new feeding waveforms, derailed stylet mechanics (N6) and cell penetration (N7). The second feeding phase consisted of salivation into the sieve element (N4-a) and sieve element sap ingestion (N4-b). Production of honeydew drops correlated with N4-b waveform patterns providing independent confirmation of this feeding behaviour.

Conclusions/Significance

Overall variation in feeding behaviour was highly correlated with previously published field resistance or susceptibility of the different rice varieties: BPH produced lower numbers of honeydew drops and had a shorter period of phloem feeding on resistant rice varieties, but there was no significant difference in the time to the first salivation (N4-b). These qualitative differences in behaviour suggest that resistance is caused by differences in sustained phloem ingestion, not by phloem location. Cluster analysis of the feeding and honeydew data split the 12 rice varieties into three groups: susceptible, moderately resistant and highly resistant. The screening methods that we have described uncover novel aspects of the resistance mechanism (or mechanisms) of rice to BPH and will in combination with molecular approaches allow identification and development of new control strategies.     

Ergosterol as an indicator of mould growth on wood in relation to culture age, humidity stress and nutrient level

Changes in ergosterol content in cultures of Penicillium brevicompactum and Aspergillus versicolor on wood with time, changes in humidity or addition of glucose solutions to wood were studied with HPLC. Lowering of the humidity level caused a very large decline in ergosterol content of cultures of P. brevicompactum on wood over a 10 day period, although small amounts remained after this time. After an initial increase, up to an inoculation time of 45 days, reductions were also observed in control samples maintained at 100% RH, but these were smaller. The amount of ergosterol decreased to very low levels in wood impregnated with low levels of glucose during a 93 day incubation period. Ergosterol concentration in hyphae produced in surface liquid cultures was shown to be higher in mycelia growing on media enriched with nitrogen or with more available nutrients. The concentration of ergosterol in the mycelia of P. brevicompactum in surface liquid cultures varied by a factor of 5 from 2 to 10 mg g⁻. The results clearly show that ergosterol present in solid materials in mainly related to active biomass. With certain prerequisites, ergosterol determinations could also be used for total fungal biomass estimations on wood.     

Between a rock and a hard place: impact of nest selection behavior on the altitudinal range of an alpine ant, Formica neorufibarbis

Formica neorufibarbis Emery is a dominant alpine ant in North America. Above timberline, colonies nest under rocks, placing brood against the rock surface to warm during the day. We tested the hypothesis that nest rock preference represents a mechanism of behavioral thermoregulation and used a demographic model to explore its impact on the species' altitudinal range. Under sunny conditions rocks provide warm microclimates. Across a 400-m altitudinal gradient from below timberline to high alpine tundra, nest rocks warmed on average 5°C above ambient at mid-day, but cooled to near ambient before dawn. Soil was warmer at mid-day under rocks occupied by ants than under randomly chosen unoccupied rocks in the same area. Occupied nest rocks were painted white or black to manipulate temperature and test its impact on colony occupancy. In addition, black-painted and white-painted rocks of similar size were placed in the field to test for a temperature effect on nest site colonization. Likelihood of nest persistence and colonization decreased under cooler, white-painted rocks and depended strongly on rock warming capacity. Experimental results showed that nest site colonization and occupancy are favored in microsites maintaining mid-day temperature ≥22°C. Across the altitudinal gradient, 66-90% of nest microsites occupied by F. neorufibarbis met this temperature threshold. Conversely, none of the exposed microsites and only 15% of those microsites under randomly selected rocks warmed to 22°C at the high altitude site (3,900 m). Results support the conclusion that nest site preference contributes to the broad altitudinal distribution of F. neorufibarbis.     

Sightability as an indicator of bias in manta tow surveys of Acanthaster planci: comment on Fernandes,Marsh, Moran and Sinclair

The manta tow technique has been extensively used in broadscale surveys of A. planci on the Great Barrier Reef (Kenchington 1984; Moran et al. 1990). Frequently the unit of interest is an entire reef, or large part thereof, although Kenchington and Morton (1976) indicated that manta tow counts could be calibrated to give accurate estimates of scuba counts over smaller reef areas. This was experimentally tested by Fernandes et al. (1990) using the concept of sightability and they conclude that The manta tow technique obviously cannot provide accurate estimates of the absolute number of starfish. The aims of this note are: (i) to indicate logical flaws in Fernandes et al. (1990) which invalidate the above conclusion; (ii) to provide a survey data set with similar characteristics to the data of Fernandes et al. (1990) which demonstrates that manta tow counts can provide accurate estimates of scuba counts; (iii) to suggest a more appropriate perspective than sightability to address questions of bias, precision and accuracy of survey data.     

Larval reaction to alcohol as an indicator of resource utilization differences between Drosophila melanogaster and D. simulans

Summary Controlled environment experiments on small epidemics of powdery mildew in mixtures of barley and wheat indicated that there was a relationship between the density of susceptible host units in the mixture and the rate of increase of disease within the stand best described by the equation: -r_m=r_s+clog_em; where r_m and r_s are epidemic rates in a mixture and a susceptible monoculture of the same overall stand density, m is the proportion of host plants in the mixture, and c is a constant. By the use of appropriate controls, it was shown that most of the reduction in epidemic rates in mixtures was attributable to the reduction in density of susceptible host units. Interception of air-borne inoculum by immune plants played a relatively minor role, although extrapolation of the results suggests that this factor might become significant if there was a sufficiently high proportion of immune to susceptible plants present.     

Immune defence, parasite evasion strategies and their relevance for 'macroscopic phenomena' such as virulence

The discussion of host-parasite interactions, and of parasite virulence more specifically, has so far, with a few exceptions, not focused much attention on the accumulating evidence that immune evasion by parasites is not only almost universal but also often linked to pathogenesis, i.e. the appearance of virulence. Now, the immune evasion hypothesis offers a deeper insight into the evolution of virulence than previous hypotheses. Sensitivity analysis for parasite fitness and life-history theory shows promise to generate a more general evolutionary theory of virulence by including a major element, immune evasion to prevent parasite clearance from the host. Also, the study of dose-response relationships and multiple infections should be particularly illuminating to understand the evolution of virulence. Taking into account immune evasion brings immunological processes to the core of understanding the evolution of parasite virulence and for a range of related issues such as dose, host specificity or immunopathology. The aim of this review is to highlight the mechanism underlying immune evasion and to discuss possible consequences for the evolutionary ecology analysis of host-parasite interactions.