Miracle-dz/UniFAR-FTUs huggingface dataset:
Cryoprotective activity of a cold-induced dehydrin purified from barley

Dehydrins are a family of proteins associated with cell dehydration. Drought, salinity, and high and low temperature may cause water loss from cells. Cold-induced dehydrins have been reported in several species. P-80 is a cold-induced 80 kDa dehydrin in barley. This protein has the same apparent molecular mass as Dhn5, previously described for barley cv Himalaya. P-80 was localized in the vicinity of vascular cylinders and in the epidermis of leaves and stems. Both tissues have been reported to be sites of early ice nucleation during controlled freezing. The present authors have proposed that this protein cryoprotects macromolecules and frost-sensitive structures. In the present study, P-80 and Dhn5 were purified with the purposes of demonstrating their cryoprotective activity in vitro, and comparing both proteins. More than 95% purity was obtained combining heat treatment, cationic exchange chromatography, preparative denaturant electrophoresis and band electroelution. Western blots showed that P-80 was the major cold-induced dehydrin in the cultivars examined in the present study. There was a major band of mRNA that showed expression kinetics consistent with P-80 accumulation. The RT-PCR picked one major band when using Dhn5-specific primers in four cold-acclimated barley cultivars. Both proteins have a similar amino acid composition, with differences in Arg, Asn + Asp, Glu + Gln, His, and Lys. The analysis of proteolytic fragments of Dhn5 and P-80 by reverse phase chromatography showed a similar pattern. Furthermore, both proteins were able to cryoprotect lactate dehydrogenase (LDH, EC 1.1.1.27) against freeze/thaw inactivation, showing a similar shape dependence on concentration and almost the same protein dosage that renders 50% of cryoprotection (PD50). Thus, P-80 and Dhn-5 share more similarities than expected for two different proteins. Their identities, though, remain to be firmly established. Further research is necessary to establish if the observed in vitro cryoprotective activity of these dehydrins is important for cryoprotection in vivo. The association of cryoprotective activity with K repeats of dehydrins is discussed.
Discovering and learning tool-use for fishing honey by captive chimpanzees

Wild chimpanzees commonly use sticks to fish for termites, ants or honey. This ability seems to be socially transmitted to juveniles by their mothers across generations. In a natural environment, the limited visibility of this behavior with regards to the extent of stick's insertion and about the success or failure in fishing hinders the study of the underlying learning processes.This study explores the discovery and learning of tool use for fishing honey in an artificial hive by a group of four captive chimpanzees. The discovery of tool use was accidental and coactive. The speed with which the group of experimentally naive chimpanzees discovered and learned tool use suggests that wild chimpanzees of different populations independently discovered the fishing behavior. The alpha male and his ally learned before the subordinates. Here, trial-and-error learning was, as in monkeys, the main process allowing the acquisition of the tool-use technique. However, the observation of conspecifics allowed the orientation of the experimentation by the selection of clues. As suggested by Tomaselloet al. (1987). it is the understanding of the function of the tool,i.e. the cause-effect relations between the action of the demonstrator, the type of tool and the task to accomplish which confer to chimpanzees and advantage over monkeys.
Arthropod Abundance in Two Maize Fields in Western Central Mexico

abstract Arthropod abundance was monitored in maize (Zea mays L.) crops on two farms located in western central Mexico during a single growing season. At the first farm (El Calvario, Michoacán), a no-tillage system was used in maize plots, while in the second farm (Singuio, Michoacán), a conventional tillage system was established. At these sites, sampling was conducted on nine occasions at seven day-intervals. Soil arthropods were captured using pitfall traps. At each sample point, maize plants were randomly selected and the number of arthropods observed on each plant was recorded. Poecilus mexicanus Chaudoir (Coleoptera: Carabidae) was the most abundant insect captured and comprised 75% (n = 2530) of the total capture of arthropods. Other carabid species together represented 18% of the total capture of arthropods at these sites and was significantly greater in the no-tillage farm compared to the conventional tillage farm. Staphylinids were the second most common group and were more abundant in the no-tillage than conventional tillage farm; Platydracus sp. Thomson (Coleoptera: Staphylinidae) was the most abundant staphylinid captured and was most abundant in the no-tillage farm. No differences between the abundance of the remaining arthropods were observed between the farms. The abundance of arthropods associated with maize plants on these two farms was not clearly affected by the type of cultivation. Over the course of the study, the abundance of fall armyworm larvae Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae) was very low (maximum 0.16 ± 0.02 insects/plot) on both farms; infestation by this pest did not differ significantly between farms. In conclusion, the no-tillage farm seemed to favor some beneficial predators present in/on the soil (e.g., carabids and staphylinids), possibly because these insects exhibit a preference for more diverse habitats and because they are more sensitive to the type and timing of cultivation practices.
A scientific note on the preparation of high molecular weight DNA from honeybee Apis mellifera L. pupae for PFGE analysis

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. A scientific note on the preparation of high molecular weight DNA from honeybee Apis mellifera L. pupae for PFGE analysis Martin Beye, Lore Grohmann, Annette Poch, Carola Burgtorf
Parallel testing of media for measuring frequencies of occurrence for Halophytophthora spp. (Oomycota) from decomposing mangrove leaves

Samples of submerged, decaying leaves of red, black, and white mangroves (Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa) were incubated on plates of eight different combinations of fungal inhibitors, bacterial inhibitors, and sporangium inducers added to a standard agar medium for isolating oomycotes (Protoctista: Oomycota; alias Oomycetes). The broad spectrum of agar preparations revealed no new oomycotic species for red or white mangroves; Halophytophthora vesicula (the delicate form) and Halophytophthora spinosa were overwhelmingly the most frequent species (to 88–90%, depending on medium, mangrove, and site). Other described species of Halophytophthora were rare (e.g., Halophytophthora bahamensis occurred twice, versus a total of 263 occurrences for H. spinosa). For black mangrove, however, the predominant oomycote (frequency ranging up to 90%, depending on medium and site) was an undescribed species of Halophytophthora with a mechanism of zoospore release involving the expansion o.
Effect of fertilization history on short-term emission of CO2 and N2O after the application of different N fertilizers – a laboratory study

Increasing organic carbon (OC) stocks in soils reduce atmospheric CO2, but may also cause enhanced N2O emissions. The objective of this study was to determine whether there are any differences in N2O and CO2 emissions from sandy arable soils with different soil OC and total nitrogen stocks due to the annual application of either farmyard manure (S-FYM) or mineral fertilizer (S-MIN) over 27 years. A laboratory incubation was performed to test the short-term effects of the application of different fertilizers [farmyard manure (FYM), KNO3 (MIN) and biogas waste (BW)] on N2O and CO2 emissions. The CO2 emission rates indicated that OC availability in the soil was higher after BW application than after FYM application. N2O emission for 53 days following fertilizer application amounted to 0.01% (MIN), 0.21% (FYM) and 24% (BW) of the total amount of N applied. The high emissions induced by BW were attributed to the combination of a high availability of OC and ammonium in the fermented waste. Fertilization history, which caused higher soil OC stocks in S-FYM, did not influence N2O emissions. The results suggest that characterization of C and N pools in organic fertilizers is required to assess their impact on N2O emissions.
Distribution of benthic diatom assemblages in Tasmanian highland lakes and their possible use as indicators of environmental changes

Classification and gradient analyses of littoral diatom assemblages and 37 chemical and physical variables in littoral sediments of 76 Tasmanian dystrophic and (ultra-)oligotrophic highland lakes indicate strong west-east gradients in pH, calcium concentration, sodium concentration, alkalinity, and gilvin, which are underlain by an oceanic-inland gradient and geological discontinuities. Two major clusters of lakes are recognised, concordant with the recognition on chemical and optical criteria of western and eastern limnological provinces and coinciding with a steep gradient in mean annual rainfall and major geological changes. Changes in species composition occur gradually across the corridor separating the two provinces. Highly significant inference models can be constructed for pH and calcium concentration and related variables, which can be used in palaeolimnological reconstructions in Tasmanian highland lakes. Resume : D'apres une classification et des analyses de gradient des assemblages de diatomees du littoral et de 37 variables chimiques et physiques observees dans des sediments littoraux de 76 lacs des hautes terres de Tasmanie, de type dystrophique et (ultra-)oligotrophe, il existe de forts gradients ouest-est de pH, de calcium, d'alcalinite et d'absorbance optique (gilvin), qui sont sous-tendus par un gradient des caracteristiques oceaniques et interieures et des discontinuites geologiques. On distingue deux grappes principales de lacs, qui correspondent a la presence, d'apres des criteres chimiques et optiques des provinces limnologiques de l'ouest et de l'est, et qui coincident avec un gradient prononce des precipitations annuelles moyennes et des grands changements geologiques. On note generalement des changements graduels dans la composition specifique en travers du corridor separant les deux provinces. On peut construire des modeles d'inference tres significatifs a partir du pH, du calcium et de variables connexes, et ceux-ci peuvent servir a reconstructions paleolimnologiques sur les lacs des hautes terres de Tasmanie. (Traduit par la Redaction)
Aposymbiosis in a cereal aphid: reproductive failure and influence on plant utilization

The central role of microbial symbioses in plant±herbivore interactions has increasingly been reported in the recent literature (Campbell, 1990; Barbosa et al., 1991; Douglas, 1994). One of the best understood examples of microbial mediation is the association between a bacterium, Buchnera, and aphids (Baumann et al., 1997). The aphid diet, phloem sap, is de®cient in essential amino acids required for insect growth and reproduction (Dadd, 1985). The endosymbiotic bacteria, located in specialized insect cells called bacteriocytes, synthesize and provision aphids with these metabolites (reviewed in Douglas, 1994; Febvay et al., 1995). Thus, these bacteria play an important role in the utilization of plants by aphids and some authors hypothesize that they are involved in host shifts and thus in the diversi®cation of this insect group (Adams & Douglas, 1997). Most studies on bacterial±aphid symbiosis, however, have focused on one aphid species, Acyrthosiphon pisum (Harris), a situation that mainly re ̄ects the amenability of this species to experimental work. To what degree are the data obtained on this species relevant to other aphid species? A ®rst attempt to widen the understanding of the aphid±bacteria association was made by Adams et al. in 1996. Comparing the effects of aposymbiosis on A. pisum and the black bean aphid, Aphis fabae (Scop.), they provided good evidence that symbiosis might not be strictly equivalent in all aphids, suggesting that comparative studies involving aphid species other than the usual model organisms were needed in order to discriminate between general and species±speci®c effects of aposymbiosis. This paper examines the unreported effects of aposymbiosis on development and reproduction in the cereal aphid Sitobion avenae (Fabr.). Using the core approach developed for studies of the aphid±Buchnera association, aphids containing bacteria (symbiotic aphids) were compared with aphids whose bacteria were eliminated with an antibiotic, with little or no direct effect on aphid viability (aposymbiotic aphids) (Prosser & Douglas, 1991; RahbeÂ et al., 1994; Liadouze et al., 1995). In addition, inspired by the recently published work of Adams & Douglas (1997) suggesting that host plants might in ̄uence the contribution of bacteria to plant utilization, the effects of aposymbiosis on two host plants were compared. Arminda, a cultivated variety of wheat Triticum aestivum L. , is a highquality host plant for S. avenae. Tm44, a line of the ancient wheat Triticum monococcum L. , is a low-quality host plant for S. avenae (Di Pietro et al., 1993; Caillaud et al., 1994). Using two host plants makes it possible to address the question ± does the effect of aposymbiosis vary with the quality of the plant on which the insect is reared?
Taxonomic revision of the genus Latrunculia Du Bocage (Porifera: Demospongiae: Latrunculiidae) in New Zealand

Abstract The genus Latrunculia in New Zealand was believed to be represented by at least three species: L. brevis Ridley & Dendy and two undescribed species. However, results from recent studies indicate that the genus contained a complex of at least eight genetically distinct species. In this paper we revise the taxonomy of Latrunculia in New Zealand and describe nine new species. Eight of these were previously identified using genetic techniques (i.e., L. kaakaariki sp. nov., L. duckworthi sp. nov., L. procumbens sp. nov., L. wellingtonensis sp. nov., L. kaikoura sp. nov., L. triverticillata sp. nov., L. fiordensis sp. nov., and L. millerae sp. nov.) and one (L. oxydiscorhabda sp. nov.) was distinguished based only on morphological differences. The species described fall into two morphological groups, spinispiraefera and triverticillata, which can be diagnosed by the number of whorls present along the discorhabd axis. The status of L. brevis, and other subantarctic species (i.e., Latrunculia bocagei, L. antarctica, L. lendenfeldi, L. spinispiraefera) is discussed; all of these species are considered to be valid but not conspecific with any of the species described here.
Case studies in the conservation of biodiversity: degradation and threats

Abstract The rating of biodiversity in arid and semiarid regions on the basis of ecological function and genetic traits of adaptation to severe environmental stresses produces significantly higher values, than that based solely on the commonly applied structural criteria of forms of life and levels of organization. The indirect driving forces of biodiversity impoverishment listed in the Global Biodiversity Strategy that are particularly effective in arid and semi-arid regions are (a) population growth, (b) economic systems and policies that fail to value the environment and its natural resources; (c) inequity in the ownership, management and flow of benefits from both the use and conservation of biological resources; and (d) weakness in legal and institutional systems. The most effective direct human impacts are (a) habitat destruction and fragmentation, (b) overexploitation of biological resources, (c) biological invasion, and (d) agriculture. The problem in arid and semiarid regions, particularly in developing countries, is exacerbated by the lack of knowledge and awareness, the paucity of research, and the diminishing number of competent systematists. This paper discusses the theoretical and practical aspects of each of the indirect driving forces, and the direct human impacts on biodiversity, and reviews case studies related to these impacts, with special reference to those carried out in arid and semiarid regions. These studies include monitoring of the human impact on land cover by remote sensing, effects of landuse on species diversity, impact of habitat fragmentation by summer resorts on coastal dunes, consequences of protection from grazing on biodiversity, comparison of biodiversity in nature reserves and the traditional ema system with that of nearby territories, and the impact of desertification on animal life and endangered species. Case studies also include the tools applied for biodiversity conservation in arid and semiarid lands with special emphasis on endangered species, restoration of degraded habitats and their biodiversity, the significance of nature reserves and captive breeding, the importance of conserving the populations below the species level throughout their geographical range of distribution, and ecotonal biodiversity.
Distribution of ATPases in wheat root membranes separated by phase partition

The distribution of divalent cation stimulated ATPase activity in relation to the distribution of other enzyme activities was studied for membrane fractions from wheat roots (Tritium aestivum L. cv. Svenno). A homogenate from dark grown plants was fractionated by differential centrifugation at 1000 g, 10,000 g, 30,000 g and 60,000 g (1, 10, 30 and 60 KP fractions), followed by partition in an aqueous polymer two-phase system, using polyethylene glycol 4000/dextran T500 concentrations of 5.7/5.7, 5.9/5.9, 6.1/6.1, 6.3/6.3 and 6.5/6.5% (w/w). The 30 KP fraction was also separated by counter-current distribution id a 6.3/6.3% two-phase system. Protein and activities of Ca2+, Mg2+, and Mn2+ stimulated ATPases. cytochrome oxidase, light induced absorbance change (LIAC) related to cyt b reductions, inosine diphosphatase and NADH dependent antimycin A insensitive cytochrome c reductase were measured. The partition of ATPase activities stimulated by Ca2+, Mg2+ or Mn2+ was similar at all polymer concentrations tested, indicating: a low cation specificity of the dominating ATPases. The distribution of ATPases. agreed with different marker enzymes in different centrifuge fractions. Divalent cation stimulated ATPases were evidently related to several of the organelles. In the different fractions the distribution of ATPase activity should then follow that of the marker enzyme of the dominant organelle. From studies with different polymer concentrations the 6.3/6.3-system was selected for further separation of the membranes in the 30 KP fraction by counter-current distribution. By this method one fraction was obtained, which probably consisted of plasmalemma and was free from mitochondrial material. Indications for plasmalemma in this fraction were a) similar partition as protoplasts and b) high LIAC activity.
Determinants and costs of natal dispersal in a lekking species

Avoidance of competition and inbreeding have been invoked as the major ultimate causes of natal dispersal, but proximate factors such as sex, body condition or birth date can also be important. Natal dispersal is expected to be of particular importance to understanding the ecological and evolutionary implications of dispersal strategies, since 1) numerous evidences suggest that individual differences in dispersal strategies are expressed early in life (i.e. at the onset of dispersal movement), 2) ultimate and proximate factors are more likely to act during this stage and 3) this stage is associated with the highest mortality rates in most vertebrates. We analysed the natal dispersal (hereafter, dispersal) behaviour in 100 marked individuals of a lekking species, the North African houbara bustards Chlamydotis undulata undulata, during four years. We investigated the effects of proximate factors on dispersal pattern and distance, as well as the mortality cost associated with movement using multievent models, allowing uncertainty in sex assignment and mixture of live recaptures and dead recoveries. Overall, males exhibited longer dispersal distances than females, contrary to the common pattern in birds. Moreover, males in poorer body condition moved further than those in better condition, whereas distance was independent of body condition in females. Finally, survival rates during dispersal were lower for females than for males and were negatively correlated with the distances covered with a similar distance-survival slope in the two sexes. Collectively, our results suggest that 1) there is substantial dispersal cost in both sexes, 2) dispersal is strongly male-biased, 3) this bias is unlikely to be explained by differential movement costs of each sex, and 4) dispersal differences found across different categories of individuals are in broad agreement with both the inbreeding avoidance and intraspecific competition mechanisms for dispersal.
Temperature- and light-dependent growth and metabolism of the invasive red algae Gracilaria vermiculophylla – a comparison with two native macroalgae

We conducted two temperature experiments to investigate the invasion success of the coarsely branched red algae, Gracilaria vermiculophylla. Our working hypothesis was that the coarsely branched G. vermiculophylla, with well-known broad environmental tolerances, would have physiological traits in-between the typical r and K strategies. A factorial experiment provided light-dependent models of growth rate at six temperatures, with maximum growth of 0.045 day−1 at 20°C. Light-saturated growth and maximum light utilization efficiency both displayed a bell-shaped temperature dependency, with optima at 21°C and 23°C respectively. The minimum light required to maintain growth was low (<1 µmol photons m−2 s−1) for lower temperatures (5–20°C) and increased exponentially to 7 µmol photons m−2 s−1 at 30°C, documenting that G. vermiculophylla has a wide tolerance to low light levels under temperature ranges occurring in the upper littoral zone in the Baltic Sea. A second experiment investigated the metabolic acclimation of G. vermiculophylla to four temperatures, while comparing its physiological responses to those of two native species, Fucus vesiculosus and Ulva lactuca. This experiment showed that the optimum temperature for light-saturated photosynthesis increased for all three species as they became long-term acclimated to higher temperatures. Short-term incubation at high temperature (30°C) was suboptimal for all three algal species when grown at low temperatures (10–15°C) but the algae were unaffected when cultured at higher temperatures (20–25°C). Finally we evaluated the capacity of each of the three species for metabolic homeostasis and found that F. vesiculosus and G. vermiculophylla had an almost identical metabolic performance regardless of acclimation temperature, whereas net photosynthesis of U. lactuca increased significantly with growth temperature. Our results show that G. vermiculophylla shares traits with both the slow-growing, leathery F. vesiculosus (K-strategy) and the fast-growing, sheet-like U. lactuca (r-strategy), by combining relatively high growth rates with a robust metabolic response to changing temperatures. In conclusion, we suggest that having both K and r metabolic traits explains, in part, the invasion success of G. vermiculophylla in temperate estuaries.