Miracle-dz/UniFAR-FTUs huggingface dataset:
How Does Fucus vesiculosus Survive Ice Scraping?

Ice covers the archipelago area of the tideless northern Baltic Sea regularly in winter and it is considered to be an important factor affecting the upper limit of Fucus vesiculosus L. , the only large perennial algal species of the area. The potential of E vesiculosus for vegetative regeneration after simulated ice scraping was tested experimentally, and untreated E vesiculosus stands growing in archipelago areas of different wave exposures were monitored in autumn and winter to record their behaviour during the period of formation of ice cover. The capacity of Fucus individuals for vegetative regeneration after simulated ice damage was considerable. Even small parts of residual holdfast tissue in minor irregularities of the rock surface were able to support regeneration after removal of the holdfast. The amount of regeneration decreased with increasing severity of the treatment. All basal parts of the thallus were equally capable of regeneration, and the most important factor affecting the amount of regenerated biomass was the amount of residual biomass. Independently of the severity of the treatment l g of residual biomass produced on average 1.3 g of new biomass during the summer period. In autumn, well before the formation of ice cover, the untreated Fucus thalli lost their buoyancy and sank to the bottom. In winter, the persistence of this behaviour was confirmed by SCUBA diving under the ice cover. The sinking phenomenon was most conspicuous in sheltered archipelago areas where the thalli grow large and often reach the water surface. Two different strategies for survival from scraping by sea ice are proposed: in exposed archipelago areas one third of the winters are totally ice free, but when a permanent ice cover is formed wind can easily break it to form pack ice, which can destroy the perennial vegetation to a depth of several meters. When the intensity of the disturbance varies from year to year, effective vegetative regeneration can be a useful strategy to keep the occasionally scraped zone occupied. In sheltered archipelago areas, ice cover is formed every year and no pack ice occurs. The ice-scraped zone extends to a depth of half a metre and varies much less than in exposed areas. Vegetative regeneration is ineffective in a zone which is regularly cleared, because the thalli never have enough time to reach the size needed for reproduction. However, the stability of the disturbed zone makes the attachment of even large surface-reaching Fucus individuals possible just below the ice cover if they can avoid freezing into it. Loss of buoyancy and sinking to the bottom seems to be an adaptation to the winter conditions of sheltered archipelago areas.
Sensitivity of Winter Wheat Phyllochron to Environmental Changes

The effect of environmental changes on the rate of leaf emergence in wheat (Triticum aestivum L.) must be understood to accurately simulate the development of the crop canopy. We determined the phyllochron for 'Stephens' winter wheat plants in growth chambers at two constant temperatures (10 and 18 °C) at a daylength of 14 h and at two constant daylengths (8 and 18 h) at a temperature of 20 °C, and for plants transferred between the two temperatures and between the two daylengths at the first-, second-, third-, and fourth-leaf stages. The phyllochron of all plants transferred from low to high temperature increased to that of plants kept continually at the high temperature [. ]
Effect of feeding in 30‐day bioaccumulation assays using Hyalella azteca in fluoranthene‐dosed sediment

Current protocols for conducting freshwater sediment bioaccumulation tests recommend that food not be added to exposures, whereas toxicity tests require food addition. To determine effects of adding food on exposure, 30‐d sediment exposures were conducted with Hyalella azteca to sediment dosed with four fluoranthene concentrations (trace level to 897 nmol/g dry weight). Accumulation was significantly greater in fed versus nonfed animals at all dose levels after 96 h of exposure and continued to be greater after 30 d in the low dose levels. At sediment concentrations above 478 nmol/g dry weight, survival of unfed animals dropped to 34% after 30 d. After 30 d of exposure, growth and reproduction were observed in fed animals exposed to sediment concentrations 20 to 90 times the expected median lethal concentration (LC50) values for fluoranthene in sediment, according to 10‐d studies reported in the literature using sediment with comparable organic carbon concentrations. Samples of sediment in exposure beakers taken from the sediment–water interface (flocculant layer) and 1 to 2 cm below the interface had large differences in fluoranthene and organic carbon concentrations. The concentration of fluoranthene was 2 to 10 times greater in the flocculant layer, the area inhabited by H. azteca, compared to the deeper sediment. These data raise questions concerning the interpretation of standard toxicity and bioaccumulation tests when food is routinely added.
Natural Variation in Abiotic Stress and Climate Change Responses in Arabidopsis: Implications for Twenty-First-Century Agriculture

Twenty-first-century agriculture faces the challenges of providing sufficient calories and nutrients to feed a growing human population despite climate change, increasing competition for freshwater from human and industrial use, and limited arable land. This review summarizes current knowledge concerning quantitative trait loci (QTL) and natural allelic variants in Arabidopsis that regulate tolerance of abiotic stresses associated with population pressure and climate change, including rising temperatures and atmospheric CO2 concentrations, drought, salinity, and mineral ion limitation and toxicity. Examples of genetic variation underlying phenotypic plasticity of abiotic stress responses are also discussed. Given the extensive resources available in Arabidopsis for QTL analysis and genome-wide association studies, along with unparalleled information on gene/gene product functions and interactions, this reference plant species provides powerful resources for translational biology approaches to improve stress tolerance and yield in crop species.
The relationship between species density and community biomass in grazed and ungrazed coastal meadows

Previous studies have indicated that the relationship between community biomass and species density can be represented by a multivariate model in which abiotic variables influence species density both through effects on biomass and through effects on the species pool. In this paper, we use data from grazed and ungrazed coastal meadows in Finland to evaluate and extend this general conceptual model of the factors controlling species density. Structural equation analysis was used to evaluate a model for all meadows and then to perform a multigroup analysis to determine how grazed and ungrazed meadows differ. By itself, biomass could explain only 12% of the variation in species density while the multivariate model was able to explain 47% using five types of predictor variables: site, soil, flooding, grazing, and biomass. Analyses found that flooding explained the greatest amount of variability in species density, primarily through negative effects on the species pool. Grazing was also found to have a strong effect on species density and results suggest that its negative influence may be largely through reductions in the species pool in grazed meadows. The most important difference found between grazed and ungrazed meadows was that species density had a strong negative relationship to biomass in the ungrazed meadows but no significant relationship in the grazed ones. Thus, it appears that the influence of competition on species density was much greater in ungrazed meadows compared to grazed ones.
Stomatal closure fully accounts for the inhibition of photosynthesis by abscisic acid.

The partial pressure of intercellular CO2 calculated from gas exchange data for abscisic acid-treated leaves of grapevine (Vitis vinifera L.) and sunflower (Helianthus annuus L.) does not indicate the average intercellular CO2 of the leaf. The latter can be determined from chlorophyll fluorescence quenching information and accurately modelled from gas exchange data. Stomatal closure can fully account for previously assumed non-stomatal inhibition of photosynthesis. Autoradiograms show that abscisic acid induces non-uniform gas exchange over small areas of the leaf.
Latitudinal differentiation in response to chilling temperatures among populations of three mangroves, Avicennia germinans, Laguncularia racemosa, and Rhizophora mangle, from the western tropical Atlantic and Pacific Panama

Upon exposure to chilling temperatures, the mangrove populations of Avicennia germinans (L.) L. , Languncularia racemosa (L.) Gaertn. , and Rhizophora mangle L. showed various amounts of leaf and plant damage that correlated with their latitudinal origin. Populations of more tropical origin showed the most chilling injury and those of more temperate origin showed less injury. The range of variation in dysfunction and chilling injury was widest among Avicennia populations, intermediate among Laguncularia populations, and narrowest among Rhizophora populations, but in each of the three mangroves, populations from northeastern Mexico had greater chilling tolerance than did those from southern Mexico, Belize, or Panama. Populations from Florida had greater chilling tolerance than did those of Jamaica and St. Croix. The most tolerant to chilling treatments were the Avicennia populations of Texas. In both leaves and roots of more tropical Avicennia plants, the lipid extracts had a greater proportion of oleic acid.
THERMOPHILIC ACTINOMYCETES ARE POTENTIAL SOURCE OF NOVEL BIOACTIVE COMPOUNDS: A REVIEW

Actinomycetes are one of the most efficient groups of microorganisms in terms of producing commercially important bioactive compounds such as enzymes, antibiotics and pigments. Among its various genera, Streptomyces, Saccharopolyspora, Amycolatopsis, Micromonospora, Actinoplanes are the major producers of industrially important biomolecules. Several species have been isolated and screened from variety of terrestrial and aquatic habitats in the past decades. Consequently the chances of isolating a novel strain of actinomycetes which could provide novel biomolecules has considerably reduced. However there is still an urgent need for discovering novel secondary metabolites to combat the problem of arising number of resistant pathogenic bacteria and increasing need of more efficient enzymes in pharmaceutical industries. For this reason, searching the less or unexplored ecosystems might lead to the discovery of novel bioactive compounds. Studies in recent years showed that the existence of actinomycetes has been reported in the unexplored extreme habitats. Among them thermophilic actinomycetes are reported to be efficient producers of new secondary metabolites that show a range of biological activities including antibacterial, antifungal and extracellular enzyme production.
Time dependent K+ currents through plasmalemma of laticifer protoplasts from Hevea brasiliensis

The purpose of our work was to investigate the functioning of K + channels in protoplasts of laticifers of Hevea brasiliensis Muell. Arg. , anastomosed into a network devoid of large central vacuoles, after tapping stress. Physiological functions such as proton pump activity and uptake of sucrose (a rubber precursor) were maintained, when the voltage-clamp method was used in vivo to record the whole-cell K + current during the stress response. A time-dependent inward current was induced in 50 mM KCl and rapidly inactivated (about 100 ms). The activation potential of this inward K + channel was not closely dependent on E K . This would be coherent with the 'valve model' of Schroeder and Fang (1991, Proc. Natl. Acad. Sci. USA 88 :11583-11587) involving the activation of a H + -pump accounting for the K + uptake observed in laticiferous cells under stress. The activation half-time of outward currents was clearly voltage dependent : from about 350 to 60 ms for 125 and 155 mV, respectively. Time-dependent outward current sensitivity to 5 mM BaCl 2 or CaCl 2 or to 5 μM Erythrosin B showed that the K + channels could be Ca 2+ -dependent. Because of the positive values of the activation potential of the outward current, the possibility opens that an action potential exists, these cells being specialized for stress response.
Differences in Root Exudation Among Phosphorus‐Starved Genotypes of Maize and Green Gram and Its Relationship with Phosphorus Uptake

Abstract Availability of phosphorus (P) in soil and its acquisition by plants is affected by the release of high and low molecular weight root exudates. A study was carried out to ascertain the qualitative and quantitative differences in root exudation among the genotypes of maize (Zea mays L.) and green gram (Vigna radiata L.) under P‐stress. Results showed that both inter‐ and intra‐species differences do exist among maize and green gram in terms of root exudation, P uptake, and shoot and root P content. In general, green gram, a legume crop, had greater root exudation compared to maize. However, the amino acid content of the total root exudates in maize was two‐fold as compared to green gram. The maize and green gram genotypes possessed genetic variability in root exudation. Irrespective of the species or genotypes, a positive relationship was found among P uptake rates, total root exudation, and shoot and root 32P content. The amount of sugars and amino acid present in the root exudates of P‐starved seedlings also add to the variation in P uptake efficiency of genotypes.
The Spatial Scale of Genetic Differentiation in a Hummingbird-Pollinated Plant: Comparison with Models of Isolation by Distance

We examined patterns of genetic differentiation at isozyme loci in natural populations of Ipomopsis aggregata, for which distances of gene flow had been previously estimated. Using genetic neighborhood areas based on direct estimates of gene flow to define subpopulations, we found that FST values (the inbreeding coefficient of a subpopulation relative to the total population) were consistently positive but small. Allele frequencies were spatially autocorrelated at distances of less than 5 m only. Both measures of genetic structure indicate some isolation by distance but less than predicted by current population genetics theory. Subpopulation size derived from realized gene flow estimates from paternity analysis produced a slightly better fit to theory than did using estimates from tracking pollen dispersal to stigmas. Discrepancies between observation and theory may also arise from other sources including occasional long-distance gene flow that is difficult to observe.
Anatomical changes to the wood of Mimosa ophthalmocentra and Mimosa tenuiflora when charred at different temperatures.

Wood retains most of its qualitative features when charred, but the dimensions and appearance of the cells change in various ways. Wood density, anatomical structure, moisture content, duration and temperature all influence wood behaviour when charred. This paper explores the qualitative changes that take place in the wood of Mimosa ophthalmocentra and M. tenuiflora when charred artificially at temperatures of 400, 600 and 800 °C and compares them with charcoal produced in a traditional temporary kiln in northeast Brazil. Our findings can be applied to interpreting the conditions in which charcoal has been produced, and document what happens qualitatively to the vessels, fibres, axial parenchyma and rays in very dense Mimosa wood (>1.00). The observations are specific to these two species.
The Fusability of Erythrocytes as a Method for Evaluating the Instability of Their Membranes

A novel approach to the study of erythrocytes instability based on assessment fusability of their plasma membrane is presented. The fusability of erythrocytes normal blood, stored for 7 days at 4°C, and type 2 patients with diabetes were studied. Human erythrocytes were fused by incubation with La3+ at final concentrations from 50 to 200 μM. Erythrocytes aggregates were incubated at 37°C for 120 min. The fusability of erythrocytes was evaluated using a light microscope. It was shown that La3+ induced extensive fusion of erythrocytes after 7 days of blood storage and erythrocytes of patients with diabetes. Incubation of normal erythrocytes at 37°C for 120 min does not induce cell fusion.
Cultural Mapping as a Social Practice: A Response to "Mapping the Cultural Boundaries in Schools and Communities: Redefining Spaces Through Organizing".

Inspired by Gerald Wood and Elizabeth Lemley’s (2015) article entitled Mapping the Cultural Boundaries in Schools and Communities: Redefining Spaces Through Organizing, this response inquires further into cultural mapping as a social practice. From our perspective, cultural mapping has potential to contribute to place making, as well as the values to sustain more equitable social futures. Thus, alongside the maps created, we longed to learn more about how the participants were engaged in mapping, how perceptions of mapping changed over time and context, how participation was mediated by relationships, and how transformation in the participants, child, youth, and adults was manifested. Making visible the richness of this experience, however, likely requires research funding, support, and time. This article is a response to: Wood, G. , & Lemley, E. (2015). Mapping the cultural boundaries in schools and communities: Redefining spaces through organizing. Democracy & Education, 23(1), Article 3. Available online at http://democracyeducationjournal.org/home/vol23/iss1/3 Introduction In “Mapping the Cultural Boundaries in School and Communities,” authors Wood and Lemley (2015) described their experiences as facilitators in Student Involvement Day (SID), a weekend program for young people between the ages of seven and 18 years old that brings together teacher education students and community members around a goal of youth empowerment. Drawing on the work of Freire and Dewey, they described their critical pedagogy linking students’ experiences with current events in Arizona, in this case the passage of Senate Bill 1070, widely viewed as antiimmigrant legislation, and House Bill 2281, which banned ethnic studies. The article highlighted cultural mapping as one of many activities used in SID and included images of the cultural maps created by three of the students based on physical locations where students felt their cultural identity was included or excluded. The “tools” young people employed to “increase inclusion of their cultural identities in multiple spaces” were also described (p. 8). We acknowledge the significance of the pedagogical work that these authors described. Their general commitment to pursuing pedagogical engagement with young people that creates the Jennifer A. Vadeboncoeur is an Associate Professor in Human Development, Learning, and Culture at the University of British Columbia. Her research focus is on alternative contexts for learning and studentteacher relationships. Shenaz A. Hanif-Shahban is a doctoral student in Human Development, Learning, and Culture. Her interests include positive psychology practices that foster wellbeing in community contexts.
Hypoxia Up-regulates Expression of Peroxisome Proliferator-activated Receptor γ Angiopoietin-related Gene (PGAR) in Cardiomyocytes: Role of Hypoxia Inducible Factor 1α

Peroxisome proliferator-activated receptors (PPAR), especially the PPARalpha and PPARgamma, are associated with an extraordinary diverse spectrum of cardiovascular diseases including hypertension, angiogenesis, cardiac hypertrophy, and atherosclerosis. PGAR (for PPAR gamma angiopoietin-related gene) is a recently identified PPAR target gene which is associated with adipose differentiation, systemic lipid metabolism, energy homeostasis, and possibly angiogenesis. We report here that WY-14643, a selective PPARalpha ligand up-regulated PGAR expression in neonatal rat cardiomyocytes. In parallel to activating the expression of vascular endothelial growth factor and glucose transporter-4, hypoxia increased PGAR mRNA levels. PGAR expression was also increased by desferrioxamine and CoCl(2), but not by sodium cyanide, results consistent with the pharmacological features of hypoxia-responsive genes. These studies are the first to demonstrate that hypoxia increases the mRNA levels of a PPAR target gene in cardiomyocytes. Furthermore, infection with adenoviral vectors encoding the wild-type or a hybrid form of HIF-1alpha highly increased PGAR mRNA levels. In contrast, neither hypoxia nor overexpression of HIF-1alpha affected the mRNA levels of PPARalpha, PPAR gamma, and muscle carnitine palmitoyltransferase, a known PPARalpha target gene. These results suggest that hypoxic activation of PGAR expression is likely mediated by HIF-1 but not the PPARalpha/RXR pathway.
Sintomas externos (morfológicos) e internos (anatômicos), observados em folhas de goiabeira (Psidium guajava L.), de plantas cultivadas em solução nutritiva com carência dos macronutrientes

The present work was carried out in order to study: (1) The symptoms of deficiency of macronutrients (N, P, K, Ca, Mg, S) in guava (Psidium guajava L.). (2) The modifications induced by those treatments in the histological make up of the leaves. Young guava plants were grown in nutrient solution two treatments being used, namely: complete solution (HOAGLAND and ARNON, 1950), deficient solution, in which a given element was ommitted. The main conclusions can be summaryzed as follows. a) Symptoms Clear cut symptoms of malnutrition were observed in the treatments: -N, -P, -Ca, -K, -Mg, and -S. The signal - stared respectively for deficient level. b) Histological effects Usually the characteristics of the chloroplasts were affected: loss of the green and coalescence into irregular bodies.
About some unusual Asiatic taxa of Isotomidae (Collembola)

Three new species and one new genus are described in this paper: Mucronia fjellbergi sp. nov, Aggresopygus sibiricus sp. et gen. nov, and A. armatus sp. nov. Additional details of morphology and distribution are provided for Micrisotoma achromata Bellinger. http://zoobank.org/urn:lsid:zoobank.org:pub:D2A206F3-F51B-479B-8930-2A7DC7522412
Nutrients, chlorophyll and biotic metrics in the Rappahannock River estuary: implications of urbanisation in the Chesapeake Bay watershed, USA

In the Chesapeake Bay watershed, various endeavours such as the inter-state agreements and Chesapeake 2000 agreement have been implemented to improve water quality and ecological conditions, and have produced mixed results at best in various tributaries. So as to evaluate the management efforts on ecological conditions in the Rappahannock River watershed, we analysed the long-term variability in land use, nutrient content and ecological biotic metrics. It appears that the inter-annual variability in nutrient loadings and concentrations is largely influenced by changes in urbanisation and climate. Significant increases in urban development (35%) and population growth have exacerbated both point and non-point nutrient pollution in the Rappahannock River. The comparatively low N : P ratio in the tidal zone, with respect to the non-tidal zone, may be due to salinity-induced P leaching from sediments regulating the water quality along the river–estuary continuum. In addition, inter-annual variability in ecological biotic metrics demonstrates degrading ecological conditions in the Rappahannock River watershed, which are primarily due to increasing watershed urbanisation driving high nutrient loadings and altered nutrient stoichiometry.