Prodiplosis longifila is reported as a pest of a wide range of species cultivated in America, including citrus, solanaceous species and asparagus. This species has different behavioural traits that ...are primarily centred on the oviposition habit and the feeding of larvae, which can change depending on the host. However, scarce information is available on population studies and the natural history of this insect, and uncertainty exists about the taxonomic identity and the geographic distribution of this species. The main objective was to perform a phylogenetic and genetic study of P. longifila populations and to define whether the North American and South American populations belong to the same species or whether a differentiation process had occurred due to geographic distance. A second objective was to determine whether this species showed genetic differentiation by host specialization in South America. The phylogenetic and population analyses based on DNA barcodes (cytochrome oxidase I gene) and a region of the ribosomal DNA (ITS2) revealed divergent clades attributable to geographic distance and host specificity. The North American and South American P. longifila insects were confirmed to be genetically distinct, and the genetic distances exceeded the values expected for intraspecific variation. In South America, the population analysis of P. longifila from tomato, sweet pepper (Solanaceae), Tahiti lime and key lime (Rutaceae) hosts evidenced high genetic differentiation between populations associated with different hosts and an absence of gene flow between these groups, suggesting the corresponding formation of cryptic species.
We summarize the ongoing scientific program of the 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF) and give an outlook into future opportunities. The program addresses important topics ...in nuclear, hadronic, and electroweak physics, including nuclear femtography, meson and baryon spectroscopy, quarks and gluons in nuclei, precision tests of the standard model and dark sector searches. Potential upgrades of CEBAF and their impact on scientific reach are discussed, such as higher luminosity, the addition of polarized and unpolarized positron beams, and doubling the beam energy.
•Changes of isoflavones in ultra-high-pressure homogenised (UHPH) soymilks under refrigerated storage.•Aglycone formation was lower in UHPH than in heat-processed samples.•In-vitro protein ...digestibility was similar during storage in heat-pasteurised and UHPH soymilks.•Blocked lysine was higher during storage in heat-pasteurised than in UHPH soymilks.
Ultra high pressure homogenisation (UHPH) is an emerging technology to obtain fine and stable soymilk emulsions. Very little information is available about the stability of this kind of product during storage. Changes of isoflavone profile, protein digestibility and lysine availability in pasteurised-UHPH soymilks were studied for 21days at 4°C in comparison to heat-pasteurised soymilks. Neither heat nor UHPH treatments affected the isoflavone profile, as the percentage of each chemical form, in comparison with unprocessed-soymilk. During storage, there was a conversion of isoflavone forms to aglycones, being higher in heat-processed samples. In addition, UHPH samples showed a lesser percentage of blocked lysine during storage. No differences were observed in the evolution of protein digestibility among samples. Therefore, UHPH treatment seems to produce a better product, due to lower amounts of aglycones, and higher protein nutritional quality than heat treatment.
The Heavy Photon Search experiment took its first data in a 2015 engineering run using a 1.056 GeV, 50 nA electron beam provided by CEBAF at the Thomas Jefferson National Accelerator Facility, ...searching for a prompt, electroproduced dark photon with a mass between 19 and 81 MeV/c2. A search for a resonance in the e+e− invariant mass distribution, using 1.7 days (1170 nb−1) of data, showed no evidence of dark photon decays above the large QED background, confirming earlier searches and demonstrating the full functionality of the experiment. Upper limits on the square of the coupling of the dark photon to the standard model photon are set at the level of 6×10−6. Future runs with higher luminosity will explore new territory.
El objetivo de este estudio fue identificar los factores que inciden en el aprendizaje en gestión tecnológica e innovación en estudiantes de administración de Medellin (Colombia) mediante el modelo ...de aceptación tecnológica. Se utilizó una metodología cuantitativa y correlacionai, basada en un análisis factorial exploratorio y un análisis factorial confirmatorio. Se recopiló información con un cuestionario basado en la escala Likert y se aplicó una encuesta a una muestra de 411 estudiantes. Los resultados mostraron la importancia de la autoeficacia, la facilidad de uso y la utilidad percibida como impulsores de procesos de aprendizaje y aceptación del valor de la gestión tecnológica e innovación. Sin embargo, persisten algunas brechas en los procesos formativos, tales como falta de asignaturas, contenidos e información suficiente alrededor del tema. Se concluye que la formación pertinente en este campo puede ser determinante para aumentar las posibilidades de empleabilidad de los profesionales en administración y para aumentar la contribución a la mejora de la competitividad y sostenibilidad empresarial.
The article examines key vectors of the development of Russia’s foreign economic relations with its largest trading partners in Latin America in the context of anti-Russian sanctions. The author ...analyzes peculiarities of Russia’s foreign trade and investment cooperation with Brazil, Ecuador, Argentina, Mexico and Chile. Factors hindering the development of this cooperation are economic instability in the world, anti-Russian sanctions, weak development of logistics networks, lack of free trade agreements, the presence of high custom duties on Russian products in the Latin American market, high competition on part of the United States and China, insufficient interest of Russian business in economic cooperation with the countries of the region over the past decades. It is shown that the largest increase in Russia’s trade turnover with the countries under consideration was recorded with Mexico, an increase in Russian exports was observed in Argentina, and imports - from Mexico. Chile demonstrated the worst indicators in the sphere of foreign trade relations among the countries under consideration. It is concluded that Russia’s largest Latin American partners have serious prospects for expanding their presence on the Russian market in the face of anti-Russian sanctions. Two key factors can be considered favorable for further development of Russia - Latin America trade cooperation. The first one is the orientation of the foreign policy of many countries in the region to other economic partners in order to minimize dependence on the United States. The second one is that Russia is shifting its vectors of economic cooperation from unfriendly countries to other countries, including Latin American states. It is concluded that investment cooperation between the countries has certain prospects for development, especially in the field of oil and gas exploration, energy and railway construction.
RmInt1 is a group II intron of Sinorhizobium meliloti which was initially found within the insertion sequence ISRm2011-2. Although the RmInt1 intron-encoded protein lacks a recognizable endonuclease ...domain, it is able to mediate insertion of RmInt1 at an intron-specific location in intronless ISRm2011-2 recipient DNA, a phenomenon termed homing. Here we have characterized three additional insertion sites of RmInt1 in the genome of S.meliloti. Two of these sites are within IS elements closely related to ISRm2011-2, which appear to form a characteristic group within the IS630-Tc1 family. The third site is in the oxi1 gene, which encodes a putative oxide reductase. The newly identified integration sites contain conserved intron-binding site (IBS1 and IBS2) and delta' sequences (14 bp). The RNA of the intron-containing oxi1 gene is able to splice and the oxi1 site is a DNA target for RmInt1 transposition in vivo. Ectopic transposition of RmInt1 into the oxi1 gene occurs at 20-fold lower efficiency than into the homing site (ISRm2011-2) and is independent of the major RecA recombination pathway. The possibility that transposition of RmInt1 to the oxi1 site occurs by reverse splicing into DNA is discussed.
E Velazquez, JM Igual, A Willems, MP Fernandez, E Munoz, PF Mateos, A Abril, N Toro, P Normand, E Cervantes, M Gillis and E Martinez-Molina
Departamento de Microbiologia y Genetica, Edificio ...Departamental, Campus Miguel de Unamuno, Universidad de Salamanca, Salamanca, Spain
Low-molecular-weight RNA analysis was performed for the identification and
classification of 20 Argentinian strains isolated from the root nodules of
Prosopis alba. SDS-PAGE of total cellular proteins, determination of the
DNA base composition, DNA--DNA reassociation experiments and physiological
and biochemical tests were also carried out for these strains and the whole
16S rRNA gene was sequenced from one of the strains, strain LMG 19008(T).
Results of the genotypic and phenotypic characterization showed that the
strains isolated in this study belong to a group that clustered in the
genus Mesorhizobium. The results of DNA--DNA hybridizations showed that
this group is a novel species of this genus. The name Mesorhizobium
chacoense sp. nov. is proposed for this species. The type strain is LMG
19008(T) (=CECT 5336(T)).
Nodulation of Medicago sativa (alfalfa) is known to be restricted to Sinorhizobium meliloti and a few other rhizobia that include the poorly characterized isolates related to Rhizobium sp. strain ...Or191. Distinctive features of the symbiosis between alfalfa and S. meliloti are the marked specificity from the plant to the bacteria and the strict requirement for the presence of sulfated lipochitooligosaccharides (Nod factors NFs) at its reducing end. Here, we present evidence of the presence of a functional nodH-encoded NF sulfotransferase in the Or191-like rhizobia. The nodH gene, present in single copy, maps to a high molecular weight megaplasmid. As in S. meliloti, a nodF homolog was identified immediately upstream of nodH that was transcribed in the opposite direction (local synteny). This novel nodH ortholog was cloned and shown to restore both NF sulfation and the Nif(^+)Fix(^+) phenotypes when introduced into an S. meliloti nodH mutant. Unexpectedly, however, nodH disruption in the Or191-like bacteria did not abolish their ability to nodulate alfalfa, resulting instead in a severely delayed nodulation. In agreement with evidence from other authors, the nodH sequence analysis strongly supports the idea that the Or191-like rhizobia most likely represent a genetic mosaic resulting from the horizontal transfer of symbiotic genes from a sinorhizobial megaplasmid to a not yet clearly identified ancestor.
The rainforest of French Guiana is still largely unaffected by human activity. Various pristine sites like the Paracou Research Station are devoted to study this tropical ecosystem. We used ...culture-independent techniques, like polymerase chain reaction-temperature gradient gel electrophoresis, and construction of clone libraries of partial 16S rRNA and nifH genes, to analyze the composition of the bacterial community in the rhizosphere of mature trees of Eperua falcata and Dicorynia guianensis, both species within the Caesalpiniaceae family. E. falcata is one of the more abundant pioneer tree species in this ecosystem and so far, no root nodules have ever been found. However, its nitrogen-fixing status is regarded as “uncertain”, whereas D. guianensis is clearly considered a non-nitrogen-fixing plant. The rhizospheres of these mature trees contain specific bacterial communities, including several currently found uncultured microorganisms. In these communities, there are putative nitrogen-fixing bacteria specifically associated to each tree: D. guianensis harbors several Rhizobium spp. and E. falcata members of the genera Burkholderia and Bradyrhizobium. In addition, nifH sequences in the rhizosphere of the latter tree were very diverse. Retrieved sequences were related to bacteria belonging to the α-, β-, and γ-Proteobacteria in the E. falcata rhizoplane, whereas only two sequences related to γ-Proteobacteria were found in D. guianensis. Differences in the bacterial communities and the abundance and diversity of nifH sequences in E. falcata rhizosphere suggest that this tree could obtain nitrogen through a nonnodulating bacterial interaction.
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