bluuebunny/crossref_metadata_2025 huggingface dataset:
Linkages between environmental conditions and recreational king mackerel (Scomberomorus cavalla) catch off west‐central Florida
Authors: WALL CARRIE C. , MULLER‐KARGER FRANK E. , ROFFER MITCHELL A.
Published: May 2009

Catch statistics for the king mackerel (Scomberomorus cavalla) recreational fishery off west‐central Florida were derived from angler interviews conducted during 19 seasonal tournaments held in April–May and October–November of 2004 and 2005. Fishing location, number of fish per line per hour (catch per unit effort), and presence of baitfish from the tournament data were examined in the context of bathymetric gradients and other benthic features (e.g., wrecks or artificial reefs), and the location and persistence of oceanic fronts mapped using satellite imagery of sea surface temperature (AVHRR) and ocean color (MODIS and SeaWiFS). Generalized linear models were applied to identify the relationship between king mackerel catch rates and environmental data. The distance of fishing activity to the nearest front varied substantially, particularly when winds and front position were variable. However, baitfish presence with proximity to water clarity fronts (as defined by water‐leaving radiance at 443 nm) significantly influenced successful king mackerel catch. Positive catch rates were significantly influenced by chlorophyll values and period (season and year). Additionally, intermediate water clarity (in the range 0.7–1.0 mW cm−2μm−1 sr−1) led to higher catch rates. Decreased water quality, primarily associated with a large Karenia brevis red tide, led to a lower number of catch and lower catch rates (122 king mackerel, 0.13 catch per unit effort) in fall 2005, compared to spring 2004 (179, 0.14), fall 2004 (360, 0.17) and spring 2005 (296, 0.21), despite a consistent seasonal effort.
Atmospheric nitrogen‐deposition may intensify phosphorus limitation of shallow epilithic periphyton in unproductive lakes
Authors: LIESS A. , DRAKARE S. , KAHLERT M.
Published: May 2009

1. We tested whether increasing atmospheric nitrogen (N) deposition along a north–south gradient intensifies epilithic phosphorus (P) limitation in oligotrophic Swedish lakes from the north to the south. We examined the epilithic community at a shallow depth from seven northern and six southern Swedish lakes, and also compared the results with a lake located geographically between the two groups. We determined lake nutrient state, epilithic nutrient ratios and epilithic algal composition, as well as grazer N : P ratios, grazer‐epilithon N : P imbalance, and N : P cycling ratios.

2. Epilithic communities appear to be generally more N‐limited in the northern lakes and more P‐limited in the southern lakes. Lake water total N (Tot‐N) and epilithic N : P ratios were lower in northern than in southern lakes and the proportion of N2‐fixing cyanobacteria was higher in northern than in southern lakes.

3. Gastropod grazers had lower N : P imbalances and cycled less N relative to P in northern than in southern lakes.

4. Atmospheric N‐deposition showed a strong positive correlation with lake water Tot‐N and a much weaker positive correlation with epilithon N : P ratios. Atmospheric N‐deposition also correlated negatively with the proportion of N2‐fixing cyanobacteria.

5. There are indications that increased atmospheric N‐deposition towards the south might intensify P‐limitation of epilithic algae and invertebrate grazers, although more studies are needed to show the strength and generality of our findings.
Contingent productivity responses to more extreme rainfall regimes across a grassland biome
Authors: HEISLER‐WHITE JANA L. , BLAIR JOHN M. , KELLY EUGENE F. , HARMONEY KEITH , KNAPP ALAN K.
Published: May 2009

Climate models predict, and empirical evidence confirms, that more extreme precipitation regimes are occurring in tandem with warmer atmospheric temperatures. These more extreme rainfall patterns are characterized by increased event size separated by longer within season drought periods and represent novel climatic conditions whose consequences for different ecosystem types are largely unknown. Here, we present results from an experiment in which more extreme rainfall patterns were imposed in three native grassland sites in the Central Plains Region of North America, USA. Along this 600 km precipitation–productivity gradient, there was strong sensitivity of temperate grasslands to more extreme growing season rainfall regimes, with responses of aboveground net primary productivity (ANPP) contingent on mean soil water levels for different grassland types. At the mesic end of the gradient (tallgrass prairie), longer dry intervals between events led to extended periods of below‐average soil water content, increased plant water stress and reduced ANPP by 18%. The opposite response occurred at the dry end (semiarid steppe), where a shift to fewer, but larger, events increased periods of above‐average soil water content, reduced seasonal plant water stress and resulted in a 30% increase in ANPP. At an intermediate mixed grass prairie site with high plant species richness, ANPP was most sensitive to more extreme rainfall regimes (70% increase). These results highlight the inherent complexity in predicting how terrestrial ecosystems will respond to forecast novel climate conditions as well as the difficulties in extending inferences from single site experiments across biomes. Even with no change in annual precipitation amount, ANPP responses in a relatively uniform physiographic region differed in both magnitude and direction in response to within season changes in rainfall event size/frequency.
Population trends of European common birds are predicted by characteristics of their climatic niche
Authors: JIGUET FRÉDÉRIC , GREGORY RICHARD D. , DEVICTOR VINCENT , GREEN RHYS E. , VOŘÍŠEK PETR , VAN STRIEN ARCO , COUVET DENIS
Published: May 2009

Temperate species are projected to experience the greatest temperature increases across a range of modelled climate change scenarios, and climate warming has been linked to geographical range and population changes of individual species at such latitudes. However, beyond the multiple modelling approaches, we lack empirical evidence of contemporary climate change impacts on populations in broad taxonomic groups and at continental scales. Identifying reliable predictors of species resilience or susceptibility to climate warming is of critical importance in assessing potential risks to species, ecosystems and ecosystem services. Here we analysed long‐term trends of 110 common breeding birds across Europe (20 countries), to identify climate niche characteristics, adjusted to other environmental and life history traits, that predict large‐scale population changes accounting for phylogenetic relatedness among species. Beyond the now well‐documented decline of farmland specialists, we found that species with the lowest thermal maxima (as the mean spring and summer temperature of the hottest part of the breeding distribution in Europe) showed the sharpest declines between 1980 and 2005. Thermal maximum predicted the recent trends independently of other potential predictors. This study emphasizes the need to account for both land‐use and climate changes to assess the fate of species. Moreover, we highlight that thermal maximum appears as a reliable and simple predictor of the long‐term trends of such endothermic species facing climate change.
Demographic effects of temperature‐dependent sex determination: will tuatara survive global warming?
Authors: MITCHELL NICOLA J. , ALLENDORF FRED W. , KEALL SUSAN N. , DAUGHERTY CHARLES H. , NELSON NICOLA J.
Published: May 2009

Global climate change is of particular concern for small and isolated populations of reptiles with temperature‐dependent sex determination because low genetic variation can limit adaptive response in pivotal temperatures, leading to skewed sex ratios. We explore the demographic consequences of skewed sex ratios on the viability of a tuatara population characterized by low genetic diversity. We studied the rare species of tuatara (Sphenodon guntheri) on the 4 ha North Brother Island in New Zealand over two nesting seasons and captured 477 individuals, with a 60% male bias in the adult population. Females first breed at 15 years and have extremely low rates of gravidity, producing clutches of three to eight eggs every 9 years. Simulations of the population using population viability analysis showed that the current population is expected to persist for at least 2000 years at hatchling sex ratios of up to 75% male, but populations with 85% male hatchlings are expected to become extinct within approximately 300 years (some eight generations). Incorporation of inbreeding depression increased the probability of extinction under male biased sex ratios, with no simulated populations surviving at hatchling sex ratios >75% male. Because recent models have predicted that climate change could lead to the production of all male S. guntheri hatchlings by 2085, we examined whether periodic intervention to produce mixed or female biased sex ratios would allow the population to survive if only males were produced in natural nests. We show that intervention every 2–3 years could buffer the effects of climate change on population sex ratios, but translocation to cooler environs might be more cost‐effective. Climate change threatens tuatara populations because neither modified nesting behaviour nor adaptive response of the pivotal temperature can modify hatchling sex ratios fast enough in species with long generation intervals.
Optimizing resiliency of reserve networks to climate change: multispecies conservation planning in the Pacific Northwest, USA
Authors: CARROLL CARLOS , DUNK JEFFREY R. , MOILANEN ATTE
Published: May 2009

The effectiveness of a system of reserves may be compromised under climate change as species' habitat shifts to nonreserved areas, a problem that may be compounded when well‐studied vertebrate species are used as conservation umbrellas for other taxa. The Northwest Forest Plan was among the first efforts to integrate conservation of wide‐ranging focal species and localized endemics into regional conservation planning. We evaluated how effectively the plan's focal species, the Northern Spotted Owl, acts as an umbrella for localized species under current and projected future climates and how the regional system of reserves can be made more resilient to climate change. We used the programmaxentto develop distribution models integrating climate data with vegetation variables for the owl and 130 localized species. We used the programzonationto identify a system of areas that efficiently captures habitat for both the owl and localized species and prioritizes refugial areas of climatic and topographic heterogeneity where current and future habitat for dispersal‐limited species is in proximity. We projected future species' distributions based on an ensemble of contrasting climate models, and incorporating uncertainty between alternate climate projections into the prioritization process. Reserve solutions based on the owl overlap areas of high localized‐species richness but poorly capture core areas of localized species' distribution. Congruence between priority areas across taxa increases when refugial areas are prioritized. Although core‐area selection strategies can potentially increase the conservation value and resilience of regional reserve systems, they accentuate contrasts in priority areas between species and over time and should be combined with a broadened taxonomic scope and increased attention to potential effects of climate change. Our results suggest that systems of fixed reserves designed for resilience can increase the likelihood of retaining the biological diversity of forest ecosystems under climate change.
Physiological and environmental regulation of interannual variability in CO2 exchange on rangelands in the western United States
Authors: POLLEY H. WAYNE , EMMERICH WILLIAM , BRADFORD JAMES A. , SIMS PHILLIP L. , JOHNSON DOUGLAS A. , SALIENDRA NICANOR Z. , SVEJCAR TONY , ANGELL RAYMOND , FRANK ALBERT B. , PHILLIPS REBECCA L. , SNYDER KEIRITH A. , MORGAN JACK A.
Published: May 2009

For most ecosystems, net ecosystem exchange of CO2 (NEE) varies within and among years in response to environmental change. We analyzed measurements of CO2 exchange from eight native rangeland ecosystems in the western United States (58 site‐years of data) in order to determine the contributions of photosynthetic and respiratory (physiological) components of CO2 exchange to environmentally caused variation in NEE. Rangelands included Great Plains grasslands, desert shrubland, desert grasslands, and sagebrush steppe. We predicted that (1) week‐to‐week change in NEE and among‐year variation in the response of NEE to temperature, net radiation, and other environmental drivers would be better explained by change in maximum rates of ecosystem photosynthesis (Amax) than by change in apparent light‐use efficiency (α) or ecosystem respiration at 10 °C (R10) and (2) among‐year variation in the responses of NEE, Amax, and α to environmental drivers would be explained by changes in leaf area index (LAI). As predicted, NEE was better correlated with Amax than α or R10 for six of the eight rangelands. Week‐to‐week variation in NEE and physiological parameters correlated mainly with time‐lagged indices of precipitation and water‐related environmental variables, like potential evapotranspiration, for desert sites and with net radiation and temperature for Great Plains grasslands. For most rangelands, the response of NEE to a given change in temperature, net radiation, or evaporative demand differed among years because the response of photosynthetic parameters (Amax, α) to environmental drivers differed among years. Differences in photosynthetic responses were not explained by variation in LAI alone. A better understanding of controls on canopy photosynthesis will be required to predict variation in NEE of rangeland ecosystems.
Electromyographic study of ejaculatory mechanism
Authors: Shafik A. , Shafik A. A. , El Sibai O. , Shafik I. A.
Published: May 2009

Cavernosus muscle (CM), seminal vesicle (SV) and vasal ampullary (VA) contractions at ejaculation are said to be reflex mechanisms (ejaculatory reflex), which have been scarcely dealt with in the literature. We investigated the hypothesis that contraction of the CMs, SVs and VA at ejaculation is a reflex action. The electromyographic (EMG) activity of CM, SV and VA during ejaculation was recorded in 28 healthy men. The test was repeated after separate anaesthetization of the glans penis (GP), CMs, SVs, and VA in the pre‐ejaculatory period. Latent ejaculatory time (LET) was calculated. CMs showed no EMG activity until rigid erection phase was reached. SVs and VA exhibited resting EMG activity which increased gradually with different stages of erection. At ejaculation, CMs, SVs and VA showed two to four intermittent contractions. The mean LET was 1.3 ± 0.2 sec. GP anaesthetization led to the disappearance of CM, SV and VA EMG activity at ejaculation, while bland gel did not affect EMG activity. CMs, SVs and VA when anaesthetized in the pre‐ejaculatory period exhibited no EMG activity at ejaculation, while saline did not affect EMG activity. Increased EMG activity of CM, SV and VA apparently denotes increase in their contractile activity. CM, SV and VA contraction on GP stimulation and ejaculation are assumed to be reflex actions and are mediated through the ‘glans‐cavernosovesicular reflex’ (GCVR) which presumably represents the ejaculatory reflex. Changes in LET or evoked response would indicate a defect in the reflex pathway. The GCVR might act as an investigative tool in diagnosing erectile dysfunction, provided further studies are performed in this respect.
Increased aneuploidy rates in spermatozoa of a male carrier of a trisomy 18 mosaicism
Authors: Perrin A. , Douet‐Guilbert N. , Le Bris M. J. , May‐Panloup P. , Guichet A. , Amice V. , Amice J. , De Braekeleer M. , Morel F.
Published: May 2009

Semen analysis of a 31‐year‐old infertile man showed a severe oligoteratozoospermia. Karyotyping of peripheral blood lymphocytes showed a 47,XY,+18[13]/46,XY[16] mosaicism. Cultured skin fibroblasts, right and left jugal smears showed 3, 50 and 65% trisomic cells respectively. The aim of the study was to evaluate the aneuploidy rates of chromosomes X, Y, 13, 18 and 21 and the diploidy rate in his spermatozoa by fluorescence in situ hybridization. The rate of disomy 18 was significantly increased in the spermatozoa of the patient (0.68%) compared to the control group (0.06%). A statistically significant difference in the rates of disomy for chromosome 13 (0.46% vs. 0.14%) and the gonosomes (0.78% vs. 0.24%) and diploidy (0.93% vs. 0.34%) was also found between the patient and the control group. However, no significant difference was observed for chromosome 21 (0.34% vs. 0.15%). Our results show evidence of a generalized perturbation of the meiotic mechanism that could lead to an increased risk for a mosaic trisomy 18 infertile male of producing offspring with aneuploidy that is not only on account of the father’s mosaicism, but also more particularly because of severe oligoteratozoospermia.
Perceptions of a service redesign by adults living with type 2 diabetes
Authors: McDowell Joan R.S. , McPhail Kathryn , Halyburton Gillian , Brown Malcolm , Lindsay Grace
Published: May 2009

Title.  Perceptions of a service redesign by adults living with type 2 diabetes.

Aim.  This article is a report of a study conducted to explore the perceptions of adults with type 2 diabetes towards the service redesign.

Background.  Diabetes is reaching epidemic proportions and the management of this chronic illness is changing in response to this challenge. In the United Kingdom, there is ongoing restructuring of healthcare services for people with chronic illnesses to ensure that their general health and clinical needs are met predominantly in primary care.

Method.  An explorative qualitative approach was used. Eight focus groups were conducted with 35 people with type 2 diabetes in one urban location between 2003 and 2004. Five focus groups were conducted with people who had recently experienced the restructured service and three groups with people who had up to 2 years’ experience of the new service. Concurrent data collection and thematic analysis were conducted by three researchers and credibility and verification sought by feedback to participants.

Findings.  Five main themes were identified: impact of living with diabetes; understanding diabetes; drivers for organizational change; care in context and individual concerns. Participants identified issues for ongoing development of the service.

Conclusion.  People with type 2 diabetes appreciate their care management within the primary care setting where there has been investment in staff to deliver this care. Healthcare resources are required to support the development of staff and the necessary infrastructure to undertake management in primary care. Policy makers need to address the balance of resources between primary and secondary care.
Areas of endemism and spatial diversification of the Muscidae (Insecta: Diptera) in the Andean and Neotropical regions
Authors: Löwenberg‐Neto Peter , De Carvalho Claudio José Barros
Published: May 2009

Aim  We present a biogeographical analysis of the areas of endemism and areas of diversification in the Muscidae. This analysis searched for geographical patterns in the Muscidae to reconstruct elements of the evolutionary biogeographical history of this insect family.

Location  Andean and Neotropical regions.

Method  We constructed a geographic database of 728 species from the literature and museum specimens. Areas of endemism were established by parsimony analysis of endemicity (PAE) based on grids of two different sizes: 5° (550 × 550 km) and 2° (220 × 220 km). Areas of diversification were delimited by track analysis that also included phylogenetic information. This process was independently applied to 11 genera. For each genus, we plotted generalized tracks generated by sister species on a map. When these generalized tracks supported inter‐generic nodes they were manually contoured and inferred to be areas of diversification for the Muscidae.

Results  Thirteen endemic areas were found using the 5° grid, and eight endemic areas resulted from the 2° grid. Ten areas were in agreement with previous studies, and 11 were new. Amazonian and Atlantic areas of diversification agreed with previous areas for the genus Polietina, and new areas of diversification were found in Panama and in central Chile.

Main conclusions  Six spatial patterns in the Muscidae were identified: (1) areas of endemism in both Pampa and Puna provinces were established with species whose distributions had not previously been analysed; (2) a new area of endemism was established in extreme southern South America, in Tierra del Fuego; (3) two new areas of diversification, which include Panama and central Chile, were identified; (4) a spatial association was identified between the separation of Chiloe Island from the continent and the diversification in Andean species; (5) a north–south track axis and latitudinal node intervals were identified, interpreted as spatial responses to glaciation or glacial retreat in the Andes; and (6) a spatial coincidence of areas of endemism, of diversification and high species richness in the Muscidae was discovered. The analysis of a complete database and the recognition of areas of diversification are extremely important in elucidating novel biogeographical patterns, which will in turn contribute to a better understanding of the geographical patterns of evolution in the Muscidae.
Effect of non‐working occlusal contacts on vertical condyle position
Authors: SEEDORF H. , WEITENDORF H. , SCHOLZ A. , KIRSCH I. , HEYDECKE G.
Published: May 2009

Summary  The presence of non‐working occlusal contacts is often considered harmful for the temporomandibular joint. Thus, the purpose of this study was to investigate the effect of non‐working occlusal contacts on the condylar position during submaximal and maximal clenching. The study comprised 22 healthy subjects having a canine‐guided occlusion. None of them had a third molar and none of them had a missing tooth or showed tooth mobility. All subjects clenched on (i) the canine, (ii) the canine while a stiff bite registration material was positioned between the second premolar and the first molar on the non‐working side. The clenching level was controlled by surface electromyography of the masseter muscle. During clenching, the vertical and horizontal condylar position was predicted using six degrees of freedom ultrasonic motion analyser. Clenching on the canine caused a cranial movement of the non‐working side condyle. This movement was reduced by 0·6–0·9 mm when the subjects clenched while the artificial non‐working side contacts were in place. These results indicate that the contacts on the non‐working side may be able to prevent upward joint movement.
Species on the menu of a generalist predator, the eastern red bat (Lasiurus borealis): using a molecular approach to detect arthropod prey
Authors: CLARE ELIZABETH L. , FRASER ERIN E. , BRAID HEATHER E. , FENTON M. BROCK , HEBERT PAUL D. N.
Published: May 2009

One of the most difficult interactions to observe in nature is the relationship between a predator and its prey. When direct observations are impossible, we rely on morphological classification of prey remains, although this is particularly challenging among generalist predators whose faeces contain mixed and degraded prey fragments. In this investigation, we used a polymerase chain reaction and sequence‐based technique to identify prey fragments in the guano of the generalist insectivore, the eastern red bat (Lasiurus borealis), and evaluate several hypotheses about prey selection and prey defences. The interaction between bats and insects is of significant evolutionary interest because of the adaptive nature of insect hearing against echolocation. However, measuring the successes of predator tactics or particular prey defences is limited because we cannot normally identify these digested prey fragments beyond order or family. Using a molecular approach, we recovered sequences from 89% of the fragments tested, and through comparison to a reference database of sequences, we were able to identify 127 different species of prey. Our results indicate that despite the robust jaws of L. borealis, most prey taxa were softer‐bodied Lepidoptera. Surprisingly, more than 60% of the prey species were tympanate, with ears thought to afford protection against these echolocating bats. Moths of the family Arctiidae, which employ multiple defensive strategies, were not detected as a significant dietary component. Our results provide an unprecedented level of detail for the study of predator–prey relationships in bats and demonstrate the advantages which molecular tools can provide in investigations of complex ecological systems and food‐web relationships.
Effects of Asobara japonica venom on larval survival of host and nonhost Drosophila species
Authors: FURIHATA SHUNSUKE X. , KIMURA MASAHITO T.
Published: May 2009

Abstract Ovipositing Asobara japonica females inject venom (containing paralysis‐inducing factors) immediately after the insertion of their ovipositors into Drosophila larvae, and lay eggs a little later. Interruption of their oviposition behaviour before egg laying causes high larval mortality in host Drosophila species, whereas normal oviposition does not. This suggests that venom of this parasitoid is toxic to larvae of these host species but its toxicity is suppressed by factor(s) provided by parasitoid females at the time of laying egg or by parasitoid embryos developing in the hosts. On the other hand, venom does not show toxicity to larvae of nonhost Drosophia species. Possible functions of venom are discussed.
Females of the weevil Zabrotes subfasciatus manipulate the size and number of eggs according to the host seed availability
Authors: TEIXEIRA ISABEL R. V. , BARCHUK ANGEL R. , MEDEIROS LUANDA , ZUCOLOTO FERNANDO S.
Published: May 2009

Abstract. In some insects, the finding of oviposition substrate triggers the uptake into oocytes of yolk proteins that are stored in the fat body during post‐embryonic development. The main host of the bean weevil Zabrotes subfasciatus (Coleoptera; Chrysomelidae; Bruchinae; Amblycerini), in which larval resources are the sole source for future egg maturation, is Phaseolus vulgaris. Despite not feeding as adults, females of this species are able to lay eggs after encountering host seeds but it is not known how females react to changes in the availability of bean seeds. In the present study, the behaviour of Z. subfasciatus facing two very different environments for oviposition is investigated, as well as how this influences offspring fitness. The results obtained show that females of Z. subfasciatus react to variations in the availability of seeds belonging to the same host species by adjusting egg size and number. Females on low bean seed density lay larger and fewer eggs than those on high bean seed density, demonstrating a trade‐off between these reproductive traits. Moreover, females can adjust egg size to changing levels of host availability during the first 4 days of their oviposition period. Although no difference in offspring weight is found, those from small eggs (low competition environment) result in larger adults. No response to selection on these traits after rearing beetles on the same host for 40 generations is observed. This unresponsiveness may indicate that beetle populations behave according to their reaction norm that already allows rapid adaptation to a varying amount of host‐seed availability and better exploitation of the environments of this widespread stored‐seed pest.
Coping with the cold: temperature and mating activity of male sagebrush crickets Cyphoderris strepitans (Orthoptera: Haglidae)
Authors: SAKALUK SCOTT K. , EGGERT ANNE‐KATRIN
Published: May 2009

Abstract. The effect of temperature on male sexual displays is well documented but its role in mediating the differential mating success of males is less well established. Male sagebrush crickets Cyphoderris strepitans Morris and Gwynne occur in high‐elevation sagebrush meadows in mountainous areas of the western U.S.A., and often are observed singing at temperatures as low −8 to −4 °C to attract sexually receptive females. Males exhibit differential mating success based on their previous mating experience: virgin males have a higher probability of obtaining a mating than do non‐virgin males of securing an additional mating. This differential mating success is mediated in part by an unusual form of nuptial feeding behaviour. Females feed on males’ hind wings at mating and the costs imposed on males as a consequence of this behaviour constrain male mating success. In the present study, to determine whether sagebrush crickets are capable of some degree of thermoregulation, and also to investigate whether this ability is influenced by male mating experience, thoracic temperatures of males of varying mating status were measured in relation to ambient temperature throughout the breeding season. A full factorial model examining the effect of site of capture, mating status, body mass and ambient temperature reveals that only ambient temperature has a significant effect on thoracic temperature after controlling for all other factors. It is concluded that differences in the calling times of virgin and non‐virgin males and their ability to secure mates does not result from differences in their ability to cope physiologically with low temperatures.
Cloning and characterization of small non‐coding RNAs from grape
Authors: Carra Andrea , Mica Erica , Gambino Giorgio , Pindo Massimo , Moser Claudio , Pè Mario Enrico , Schubert Andrea
Published: May 2009

Small non‐coding RNAs, including microRNAs (miRNAs) and small interfering RNAs (siRNAs), are effectors of regulatory pathways underlying plant development, metabolism, and responses to biotic and abiotic stresses. To address the nature and functions of these regulators in grapevine (Vitis vinifera L.), we have produced a small RNA library from mixed‐stage grape berries. Thirteen conserved miRNAs belonging to nine miRNA families, a non‐conserved miRNA, and four putative non‐conserved miRNAs were isolated, and their expression and targets are described. Experimentally validated targets of non‐conserved miRNAs and putative miRNAs included three genes encoding NB‐LRR proteins and a gene encoding a heavy metal ion transport/detoxification protein. Of the endogenous and pathogen‐derived siRNAs that were also isolated, four endogenous siRNAs mapped to genes encoding RD22‐like proteins and two to a gene encoding a cytokinin synthase. The siRNA id65 targeted the cytokinin synthase gene transcript with antisense complementarity, and was specifically expressed in mature berries, in which, by contrast, expression of the cytokinin synthase gene was strongly repressed. 5′ RACE revealed that the transcript of this gene was processed in 21 nucleotide increments from the id65 cleavage site, and that further cleavage was mediated by secondary siRNAs in cis. These results indicate that grapevine miRNA‐ and siRNA‐mediated regulatory circuits have evolved to comprise processes associated with defence and fruit ripening, and broaden the range of small RNA‐mediated regulation, which was previously associated with auxin, ABA, gibberellins and jasmonate, to encompass cytokinin metabolism.
Tunisian hereditary spastic paraplegias: clinical variability supported by genetic heterogeneity
Authors: Boukhris A , Stevanin G , Feki I , Denora P , Elleuch N , Miladi MI , Goizet C , Truchetto J , Belal S , Brice A , Mhiri C
Published: May 2009

Hereditary spastic paraplegias (HSP) constitute a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by slowly progressive spasticity of the lower extremities. We performed the first clinical, epidemiological and genetic study of HSP in Southern Tunisia. We investigated 88 patients belonging to 38 unrelated Tunisian HSP families. We could establish the minimal prevalence of HSP in the district of Sfax at 5.75/100,000. Thirty‐one percent of the families had a pure HSP, whereas 69% had a complicated form. The mode of inheritance was almost exclusively compatible with an autosomal recessive trait (97%, 37/38). Taking into account previously published results and new data generated in this work, genetic studies revealed significant or putative linkage to known HSP loci in 13 families (34.2%) to either SPG11 (7/38, 18.4%), SPG15 (4/38, 10.5%) or to SPG4 and SPG5 in one family each. The linkage results could be validated through the identification of two recurrent truncating mutations (R2034X and M245VfsX246) in the SPG11 gene, three different mutations (Q493X, F683LfsX685 and the novel S2004T/r.?) in the SPG15 gene, the recurrent R499C mutation in the SPG4 gene as well as the new R112X mutation in the SPG5 gene. SPG11 and SPG15 are the major responsible HSP genes in Tunisia.
Chemoimmunotherapy: an emerging strategy for the treatment of malignant mesothelioma
Authors: McCoy M. J. , Nowak A. K. , Lake R. A.
Published: May 2009

Whether the immune system can recognize malignant and premalignant cells and eliminate them to prevent the development of cancer is still a matter of open debate, but in our view, the balance of evidence favours this concept. Nonetheless, the International Agency for Research on Cancer has now predicted that cancer will overtake heart disease as the leading cause of death worldwide by 2010, showing that this protective mechanism often fails. Malignant mesothelioma has traditionally been considered a relatively non‐immunogenic cancer. However, mesothelioma cells do express a set of well‐defined tumour antigens that have been shown to engage with the host immune system. Mesothelioma should therefore be considered a target for immunotherapy. A variety of anticancer immunotherapies have been investigated in mesothelioma and in other malignancies, although these have been largely ineffective when used in isolation. Over recent years, there has been increasing interest in the possibility of combining immunotherapy with chemotherapy in the fight against cancer. Here, we discuss the rationale behind combining these two, long considered antagonistic, treatment options in the context of malignant mesothelioma.
A proficiency testing study to evaluate laboratory performance for the detection of different genotypes of parvovirus B19
Authors: Baylis S. A. , Buchheit K. H.
Published: May 2009

Background and Objectives  In Europe, it is a regulatory requirement that parvovirus B19 (B19V) DNA nucleic acid amplification technique‐based testing is performed on plasma pools for certain classes of plasma‐derived medicinal products. This proficiency testing study set out to examine the ability of public quality control laboratories and plasma fractionation organizations to detect different genotypes of B19V using nucleic acid amplification technique‐based assays.

Materials and Methods  Laboratories were supplied with cloned DNAs representing the main genotypes of B19V. All samples were adjusted to equivalent copy number and were distributed as part of a routine external quality assessment programme investigating the evaluation of B19V containing plasma samples by these laboratories. The plasmid clones were distributed to 25 laboratories, representing 13 quality control laboratories and 12 manufacturers of plasma derivatives. The criteria for acceptable detection of the different genotypes of B19V DNA was based upon the maximum theoretical efficiency for polymerase chain reaction amplification. Proficient laboratories were deemed to be those reporting results within 1 log10 dilution for each of the different virus genotypes.

Results  Data were returned by 23 of the participating laboratories. Some laboratories returned data for more than one type of assay and in total 27 data sets were analysed. Nine of the participating laboratories were able to successfully detect all the virus genotypes according to the applied criteria, all except one used in‐house assays.

Conclusions  The results of the study highlight that there are still discrepancies in the detection of a broad spectrum of B19V genotypes, with implications for batch release testing.
Nutritional niche separation in coexisting bog species demonstrated by 15N‐enriched simulated rainfall
Authors: CLARKSON BEVERLEY R. , SCHIPPER LOUIS A. , SILVESTER WARWICK B.
Published: May 2009

Empodisma minus and Sporadanthus ferrugineus (both Restionaceae) coexist in New Zealand raised bogs, yet Sporadanthus have significantly more depleted 15N natural abundance signatures than coexisting Empodisma. Their root systems are spatially separated with Empodisma having a thick surface layer of about 50 mm of cluster roots overlying the deeper Sporadanthus roots. We hypothesized this root displacement allows Empodisma to preferentially access the primary N input from rainfall, thus establishing niche separation, and tested this using tracer stable isotopes. We aerially applied 1.6 mmol m−2 of 15N as (NH4)2SO4 chased by deionized water to simulate a rainfall event of 34 L m−2. Root/peat matrix cores were harvested after 5 h and analysed for 15N uptake. Approximately 80% of the tracer applied was recovered in the cores, with 90% of this recovered in the upper Empodisma cluster root layer. Seven weeks after application, young shoots of Empodisma were significantly enriched (mean δ15N = +7.21‰; reference = −0.42‰), whereas those of coexisting Sporadanthus were not (mean δ15N = −2.76‰; reference = −4.24‰). However, we were unable to quantify the 15N uptake because of the dilution effect of the large biomass. We calculated the contribution of biological nitrogen fixation as a possible alternative source of N in achieving niche separation. The acetylene reduction assay showed minor amounts of nitrogenase activity are associated with Empodisma and Sporadanthus roots (equivalent to 0.045 ± 0.019 and 0.104 ± 0.017 kg N ha−1 year−1 respectively). Our results suggest that the species acquire nutrients from different rooting zones, with Empodisma accessing nutrients at the surface from rainfall and Sporadanthus accessing nutrients from mineralization in deeper peat layers. Such niche differentiation probably facilitates species coexistence and may provide a mechanism for slowing the rate of competitive displacement during long‐term succession.
Predicting the unexpected: using a qualitative model of a New Zealand dryland ecosystem to anticipate pest management outcomes
Authors: RAMSEY DAVID S. L. , NORBURY GRANT L.
Published: May 2009

Pest management is expensive and there is often uncertainty about the benefits for the resources being protected. There can also be unintended consequences for other parts of the ecosystem, especially in complex food webs. In making decisions managers generally have to rely on qualitative information collected in a piecemeal fashion. A method to assist decision making is a qualitative modelling approach using fuzzy cognitive maps, a directed graphical model related to neural networks that can take account of interactions between pests and conservation assets in complex food webs. Using all available information on relationships between native and exotic resources and consumers, we generated hypotheses about potential consequences of single‐species and multi‐species pest control on the long‐term equilibrium abundances of other biotic components of an ecosystem. We applied the model to a dryland ecosystem in New Zealand because we had good information on its trophic structure, but the information on the strength of species interactions was imprecise. Our model suggested that pest control is unlikely to significantly boost native invertebrates and lizards in this ecosystem, suggesting that other forms of management may be required for these groups. Most of the pest control regimes tested resulted in greater abundances of at least one other pest species, which could potentially lead to other management problems. Some of the predictions were unexpected, such as more birds resulting from possum and mouse control. We also modelled the effects of an increase in invasive rabbits, which led to unexpected declines of stoats, weasels, mice and possums. These unexpected outcomes resulted from complex indirect pathways in the food web. Fuzzy cognitive maps allow rapid construction of prototype models of complex food webs using a wide range of data and expert opinion. Their utility lies in providing direction for future monitoring efforts and generating hypotheses that can be tested with field experiments.
Biodiversity recovery during rainforest reforestation as indicated by rapid assessment of epigaeic ants in tropical and subtropical Australia
Authors: PIPER SCOTT D. , CATTERALL CARLA P. , KANOWSKI JOHN J. , PROCTOR HEATHER C.
Published: May 2009

There is growing interest in the potential for reforestation to assist the recovery of rainforest biodiversity. There is also a need to identify taxonomically tractable groups for use as cost‐effective indicators when monitoring the status of biodiversity within reforested sites. Insects are an important component of terrestrial biodiversity but often require considerable resources to sample at species level. Ant genera and generic‐based functional groups have been suggested as possible indicators of environmental disturbance. Here we ask to what extent the development of biodiversity is indicated by epigaeic ant genera and functional groups, across different types of reforestation in tropical and subtropical Australia. In each region, we used pitfall traps to sample the ants in replicate sites of: unmanaged regrowth, monoculture and mixed species plantations and ‘ecological restoration’ plantings, together with reference sites in pasture and rainforest. We recorded 35 epigaeic ant genera (and 4623 individuals) from 50 tropical sites, and 39 genera (and 9904 individuals) from 54 subtropical sites, with 47 genera overall. Community composition of both genera and functional groups differed between pasture and rainforest, although many genera were widespread in both. Reforested sites were intermediate between pasture and rainforest in both regions, and showed a gradient associated with decreasing grass and increasing tree and litter cover. Older monoculture plantations and ecological restoration plantings had the most rainforest‐like ant assemblages, and mixed‐species cabinet timber plots the least, of the reforested sites. We conclude that ground‐active ant genera and functional groups sampled in rapid surveys by pitfall‐trapping showed only a modest ability to discriminate among different types of reforestation. Species‐level identification, perhaps together with expanded sampling effort, could be more informative, but would require resourcing beyond the scope of rapid assessments.
Gap‐crossing decisions of forest birds in a fragmented landscape
Authors: ROBERTSON OLIVER J. , RADFORD JAMES Q.
Published: May 2009

Habitat loss and fragmentation are recognized as primary drivers of biodiversity loss worldwide. To understand the functional effects of habitat fragmentation on bird populations, data on movement across gaps in habitat cover are necessary, although rarely available. In this study, we used call playback to simulate a conspecific territorial intruder to entice birds to move through the landscape in a predictable and directional manner. We then quantified the probability of movement in continuous forest and across cleared gaps for two forest‐dependent species, the grey shrike‐thrush (Colluricincla harmonica) and the white‐throated treecreeper (Cormobates leucophaeus). Fifty‐four playback trials were conducted for each species across distances ranging from 25 to 480 m in continuous forest and 15–260 m across gaps in a forest‐agricultural landscape in southern Victoria, Australia. The probability of movement was significantly reduced by gaps in forest cover for both species. Shrike‐thrushes were six times more likely to move 170 m in continuous forest than to cross 170‐m gaps. The mean probability that treecreepers would cross any gap at all was less than 0.5, and they were three times less likely to move 50 m across a gap than through continuous forest. Both species displayed non‐linear responses to increasing gap distance: we identified a gap‐tolerance threshold of 85 m for the shrike‐thrush and 65 m for the treecreeper beyond which individuals were most unlikely to cross. The presence of scattered paddock trees increased functional connectivity for the shrike‐thrush, with individuals crossing up to 260 m when scattered trees were present. We conclude that gaps in habitat cover are barriers to movement, and that characteristics of the intervening matrix influence landscape permeability.
Misprescription and misuse of one‐tailed tests
Authors: LOMBARDI CELIA M. , HURLBERT STUART H.
Published: May 2009

One‐tailed statistical tests are often used in ecology, animal behaviour and in most other fields in the biological and social sciences. Here we review the frequency of their use in the 1989 and 2005 volumes of two journals (Animal BehaviourandOecologia), their advantages and disadvantages, the extensive erroneous advice on them in both older and modern statistics texts and their utility in certain narrow areas of applied research. Of those articles with data sets susceptible to one‐tailed tests, at least 24% inAnimal Behaviourand at least 13% inOecologiaused one‐tailed tests at least once. They were used 35% more frequently with nonparametric methods than with parametric ones and about twice as often in 1989 as in 2005. Debate in the psychological literature of the 1950s established the logical criterion that one‐tailed tests should be restricted to situations where there is interest only in results in one direction. ‘Interest’ should be defined; however, in terms of collective or societal interest and not by the individual investigator. By this ‘collective interest’ criterion, all uses of one‐tailed tests in the journals surveyed seem invalid. In his bookNonparametric Statistics,S. Siegel unrelentingly suggested the use of one‐tailed tests whenever the investigator predicts the direction of a result. That work has been a major proximate source of confusion on this issue, but so are most recent statistics textbooks. The utility of one‐tailed tests in research aimed at obtaining regulatory approval of new drugs and new pesticides is briefly described, to exemplify the narrow range of research situations where such tests can be appropriate. These situations are characterized by null hypotheses stating that the difference or effect size does not exceed, or is at least as great as, some ‘amount of practical interest’. One‐tailed tests rarely should be used for basic or applied research in ecology, animal behaviour or any other science.