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Orthogonality constrained gradient reconstruction for superconvergent linear functionals
The post-processing of the solution of variational problems discretized with Galerkin finite element methods is particularly useful for the computation of quantities of interest. Such quantities are generally expressed as linear functionals of the solution and the error of their approximation is bounded by the error of the solution itself. Several a posteriori recovery procedures have been developed over the years to improve the accuracy of post-processed results. Nonetheless such recovery methods usually deteriorate the convergence properties of linear functionals of the solution and, as a consequence, of the quantities of interest as well. The paper develops an enhanced gradient recovery scheme able to both preserve the good qualities of the recovered gradient and increase the accuracy and the convergence rates of linear functionals of the solution
Quantification of the mycorrhizal fungal community associated with a modern wheat cultivar (Triticum aestivum) and with a wheat ancestor.
Abstract: Plant breeding is an important instrument to improve crop productivity. However, studies have shown that plant breeding, as well as the use of management practices such as tillage and fertilization, influence the plant root microbiome and also may have caused reduction in the genetic diversity of modern cultivars when compared to their ancestors. As the rhizosphere microbiome can profoundly impact plant growth, nutrition and health, we hypothesized that plant breeding can negatively affect the recruitment of beneficial microbes in the rhizosphere and interactions with their favorable microbial partners. A greenhouse experiment was conducted to assess the composition of the rhizosphere mycorrhizal fungi community in wheat (Triticum aestivum) varieties, modern cultivars and wheat ancestors. Plants were grown in forest and agricultural soils, collected in wheat cultivation area in SĂŁo Paulo, Brazil. The DNA was extracted from rhizospheric soil collected in the flowering stage, and the r RNA 18S gene copy number of mycorrhizal fungi was determined using quantitative real-time PCR (qPCR). The bulk soil presented less mycorrhizal fungi than rhizospheric soil of modern cultivars and more than rhizospheric soil of wheat ancestors indicating that these materials can be more selective in recruiting and structuring the rhizosphere microbiome. Modern cultivars were more intensely colonized by mycorrhizal fungi compared to ancestral genotypes and therefore possibly more dependent on these microorganisms. The results do not evidence that new crop plant genotypes lost their ability to respond to mycorrhizal due to agricultural and breeding practices, and further analyses needs to be performed
Effect of phosphorus limitation on the microbial community assembly in the common bean (Phaseolus vulgaris L.) rhizosphere.
Abstract: The indiscriminate use of inputs in agricultural systems, particularly phosphate, combined with the need of growing food production, is causing the depletion of phosphorus mines around the world. In order to mitigate the environmental impact caused by phosphorus exploration microorganisms can be used to increase the efficiency of phosphorus utilization in crop systems by promoting nutrient solubilization and absorption. It is believed that low phosphorus concentration in soil, enriches specific members of the rhizosphere microbiome related to the availability of this element to the plant. In this study, a factorial experiment was performed considering contrasting cultivars in the uptake efficiency of phosphorus (being IAC-Imperador and DOR-364, the cultivar with high and low efficiency in P uptake); using soil with low P content and enriched concentrations of rock phosphate and single superphosphate. The rhizosphere microbiome was accessed using TSA and NBRIP media, to estimate total bacterial colony-forming units and identify isolates with potential of P solubilization, respectively. Total DNA was extracted and mycorrhizal fungi community was quantified using qPCR. The number of total bacteria colony-forming unit increased in the single superphosphate treatments of the IAC-Imperador (p<0.01), but not in DOR-364. Phosphorus solubilizing bacteria abundance also showed increase in single superphosphate treatments in both cultivars (p<0.01). Rock phosphate treatments did not showed any significant differences in colony-forming unit abundances. When considering the cultivar with higher efficiency in phosphorus uptake, the abundance of mycorrhizal fungi did not differed significantly. On the other hand, the lower efficient cultivar showed 5-fold increase with the addition of single superphosphate, and a 10-fold increase with rock phosphate (p<0.01). The results suggest that different type of P and the plant variety assembles the microbial community that helps plants in P uptake. The recruitment of mycorrhizal fungi is higher in the cultivar less efficient in phosphorus uptake, mainly when in the presence of phosphate rock
Endpoint thermodynamics of an atomic Fermi gas subject to a Feshbach resonance
The entropy and kinetic, potential, and interaction energies of an atomic
Fermi gas in a trap are studied under the assumption of thermal equilibrium for
finite temperature. A Feshbach resonance can cause the fermions to pair into
diatomic molecules. The entropy and energies of mixtures of such molecules with
unpaired atoms are calculated, in relation to recent experiments on molecular
Bose-Einstein condensates produced in this manner. It is shown that, starting
with a Fermi gas of temperature , where is the
non-interacting Fermi temperature, an extremely cold degenerate Fermi gas of
temperature may be produced without further evaporative
cooling. This requires adiabatic passage of the resonance, subsequent sudden
removal of unpaired atoms, and adiabatic return. We also calculate the ratio of
the interaction energy to the kinetic energy, a straightforward experimental
signal which may be used to determine the temperature of the atoms and indicate
condensation of the molecules.Comment: 12 pages, 5 figure
Composition and functionality of the wild and cultivated common bean rhizosphere microbiome.
Abstract: Plants rely on their rhizosphere microbiome for specific functions, such as, nutrient acquisition and protection against diseases. The domestication and subsequent plant breeding neglected the important role of the rhizosphere microbiome on plant performance. Here, we tested the hypothesis that ancestor materials have higher ability to host beneficial microorganisms in the rhizosphere when compared to modern cultivars. For this, we assessed the composition and functionality of the rhizosphere microbiome associated with a wild (Wild Mex) and with a cultivated (IAC Alvorada) common bean grown in highly biodiverse soil (Amazonian Dark Earth). Antagonistic bacteria were isolated from common bean rhizosphere and total rhizosphere DNA was extracted for shotgun sequencing using Illumina MiSeq. Eleven out of 104 isolated bacteria showed antagonistic in vitro activity against soil borne pathogens Rhizoctonia solani and Fusarium oxysporum f. sp. phaseoli. The bacterial isolates were identified belonging to Streptomyces, Kitasatospora, Alcaligenes, Achromobacter, Pseudomonas, Stenotrophomonas, Brevibacillus and Paenibacillus genus. The cultivation-independent approach revealed that microbial community composition in the Wild Mex bean rhizosphere was characterized by higher relative abundance of bacterial phyla Acidobacteria, Verrucomicrobia, Gemmatimonadetes and fungal phylum Glomeromycota when compared with IAC Alvorada cultivated bean, which showed a higher relative abundance of bacterial phyla Firmicutes, Planctomycetes, Deinococcus-Thermus and fungal phylum Ascomycota. Wild Mex rhizosphere microbiome showed higher relative frequency of nitrogen-fixing, nitrifying, antagonists and plant growth promoting microorganisms. The wild bean also showed higher relative abundance of functions related to nitrogen fixation, siderophore and indole acetic acid (IAA) production, when compared with IAC Alvorada bean. Ordination analysis revealed that the wild genotype is more selective in recruiting microorganisms and functions in the rhizosphere when compared with modern cultivar. In conclusion, the results revealed that domestication and plant breeding potentially undermined rhizosphere microbiome composition and functions debilitating the host?s ability to select and support beneficial microbes
Discopyge castelloi, Castello's Apron Numbfish
Castello's Apron Numbfish (Discopyge castelloi) is a small (to at least 31 cm total length) ray that occurs in the Southwest Atlantic from Necochea, Buenos Aires, to Camarones, Chubut, Argentina. It inhabits the inner continental shelf at depths of 35–56 m. Its depth range suggests that it is exposed to commercial and artisanal demersal trawl fisheries. Commercial fishing began in Argentina in the late 1800s, became industrialized after World War II, and increased rapidly in the 1980s. By 1992 there were over 300 coastal trawlers. This number increased to over 400 in 2015, and the number of fishing trips undertaken by that fleet nearly doubled from over 7,600 to nearly 14,000 over that time frame. The overall number of fishing vessels in operation in Argentina has grown from under 300 in 1990 to nearly 1,000 in 2015. This species has however been caught only rarely, and may have either a low catchability or a depth range deeper than is currently known. Further research is needed on distribution, life history, population size and trend, and threats. Since it is unknown whether fishing is causing a population reduction, there is currently inadequate information available to assess Castello's Apron Numbfish beyond Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". EstaciĂłn HidrobiolĂłgica de Puerto QuequĂ©n (sede QuequĂ©n); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Dipturus argentinensis, argentine skate
The Argentine Skate (Dipturus argentinensis) occurs in the Southwest Atlantic from central Chubut to southern Santa Cruz, Argentina and off the northwest Falkland Islands (Malvinas). It inhabits continental and insular shelves and slopes at depths of 85–400 m. Maximum size is unknown as only immature specimens have been caught (up to 125 cm total length) and there is some question as to where the adult population occurs. This skate is captured in commercial demersal trawl fisheries, which are intense across its entire known geographic and bathymetric range. It is captured in the target trawl fishery for skates off the Falkland Islands (Malvinas). Identification is an issue, and it may be captured more than is perceived. More information is needed to determine the level of overlap with fisheries and this species' catchability and sensitivity to fishing. Research is needed on distribution, life history, population size and trends, and threats. Since it is unknown whether fishing is causing a population reduction, there is currently inadequate information available to assess the Argentine Skate beyond Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". EstaciĂłn HidrobiolĂłgica de Puerto QuequĂ©n (sede QuequĂ©n); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Pompert, J.. Georgia Seafoods; PaĂses BajosFil: Herman, K.. Georgia Aquarium; Estados Unido
The echocardiography diagnosis of cor pulmonale in a horse
The authors describe the two-dimensional and Doppler signs that characterize the pulmonary hypertension caused by chronic obstructive pulmonary disease (COPD) in a horse
A Systematic Review of Pharmacologic and Rehabilitative Treatment of Small Fiber Neuropathies
The aim of this systematic review is to guide the physician in defining the pharmacologicand rehabilitative therapeutic approaches for adopting the best strategies described in the currentliterature. The search was conducted in PubMed, EMBASE, Cochrane Library and Web of Scienceto identify the treatment of small fiber neuropathies. Two reviewers independently reviewed andcame to a consensus on which articles met inclusion/exclusion criteria. The authors excluded theduplicates, animal studies and included the English articles in which the treatment of patients withsmall fiber neuropathies was described. The search identified a total of 975 articles with the keywords“small fiber neuropathy” AND “rehabilitation” OR “therapy” OR “treatment”. Seventy-eight selectedfull-text were analyzed by the reviewers. Forty-two publications met the inclusion criteria and wereincluded in the systematic review to describe the rehabilitative and pharmacologic treatment of smallfiber neuropathies. Despite the range of different protocols of treatment for small fiber neuropathy,other robust trials are needed. In addition, always different therapeutic approaches are used; a uniqueprotocol could be important for the clinicians. More research is needed to build evidence for the beststrategy and to delineate a definitive therapeutic protocol
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