Search results for "APR"

Bacterioplankton Community Composition Along Environmental Gradients in Lakes From Byers Peninsula (Maritime Antarctica) as Determined by Next-Genera…

2019

This study comprises the first attempt to describe the planktonic bacterial communities of lakes from Byers Peninsula, one of the most significant limnological districts in the Maritime Antarctica, leveraging next-generation sequencing (NGS) technologies. For the survey, we selected 7 lakes covering the environmental gradient from inland to coastal lakes, some of them sampled both in surface and deep waters. Analysis provided just over 85,000 high quality sequences that were clustered into 864 unique Zero-radius Operational Taxonomic Units (ZOTUs) (i.e., 100% sequence similarity). Yet, several taxonomic uncertainties remained in the analysis likely suggesting the occurrence of local bacteri…

Functional Metabolic Diversity of Bacterioplankton in Maritime Antarctic Lakes

2021

A summer survey was conducted on the bacterioplankton communities of seven lakes from Byers Peninsula (Maritime Antarctica), differing in trophic and morphological characteristics. Predictions of the metabolic capabilities of these communities were performed with FAPROTAX using 16S rRNA sequencing data. The versatility for metabolizing carbon sources was also assessed in three of the lakes using Biolog Ecoplates. Relevant differences among lakes and within lake depths were observed. A total of 23 metabolic activities associated to the main biogeochemical cycles were foreseen, namely, carbon (11), nitrogen (4), sulfur (5), iron (2), and hydrogen (1). The aerobic metabolisms dominated, althou…

Dematiaceous Hyphomycetes from Quercus suber litter

2011

Phylogenetic analysis of Sicilian goats reveals a new mtDNA lineage.

2006

The mitochondrial hypervariable region 1 (HVR1) sequence of 67 goats belonging to the Girgentana, Maltese and Derivata di Siria breeds was partially sequenced in order to present the first phylogenetic characterization of Sicilian goat breeds. These sequences were compared with published sequences of Indian and Pakistani domestic goats and wild goats. Mitochondrial lineage A was observed in most of the Sicilian goats. However, three Girgentana haplotypes were highly divergent from the Capra hircus clade, indicating that a new mtDNA lineage in domestic goats was found.

Assessing first-year engineering students' pre-university mathematics knowledge: preliminary validity results based on an item response theory model

2020

The importance of students’ prior knowledge to their current learning outcomes cannot be overemphasised. Students with adequate prior knowledge are better prepared for the current learning materials than those without the knowledge. However, assessment of engineering students' prior mathematics knowledge has been beset with a lack of uniformity in measuring instruments and inadequate validity studies. This study attempts to provide evidence of validity and reliability of a Norwegian national test of prior mathematics knowledge using an explanatory sequential mixed-methods approach. This approach involves use of an item response theory model followed by cognitive interviews of some students …

Educación Física: aprendizaje en acción integrando Mobile Learning, Tablets y Apps

2016

Los objetivos del trabajo son: conocer las posibilidades y limitaciones de los dispositivos móviles y las Apps en la enseñanza-aprendizaje de la EF; saber qué instrumentos específicos se pueden utilizar, especialmente durante las clases; conocer las aplicaciones didácticas que tienen tabletas, teléfonos inteligentes y Apps específicas. También, establecer criterios y estrategias para integrar eficazmente los dispositivos móviles en la EF y en las ciencias del deporte

Isolation and Characterization of Novosphingobium sp. Strain MT1, a Dominant Polychlorophenol-Degrading Strain in a Groundwater Bioremediation System

2002

ABSTRACT A high-rate fluidized-bed bioreactor has been treating polychlorophenol-contaminated groundwater in southern Finland at 5 to 8°C for over 6 years. We examined the microbial diversity of the bioreactor using three 16S ribosomal DNA (rDNA)-based methods: denaturing gradient gel electrophoresis, length heterogeneity-PCR analysis, and restriction fragment length polymorphism analysis. The molecular study revealed that the process was dependent on a stable bacterial community with low species diversity. The dominant organism, Novosphingobium sp. strain MT1, was isolated and characterized. Novosphingobium sp. strain MT1 degraded the main contaminants of the groundwater, 2,4,6-trichloroph…

Side-stepping secondary symbionts: widespread horizontal transfer across and beyond the Aphidoidea.

2003

To elucidate the co-evolutionary relationships between phloem-feeding insects and their secondary, or facultative, bacterial symbionts, we explore the distributions of three such microbes--provisionally named the R-type (or PASS, or S-sym), T-type (or PABS), and U-type--across a number of aphid and psyllid hosts through the use of diagnostic molecular screening techniques and DNA sequencing. Although typically maternally transmitted, phylogenetic and pairwise divergence analyses reveal that these bacteria have been independently acquired by a variety of unrelated insect hosts, indicating that horizontal transfer has helped to shape their distributions. Based on the high genetic similarity b…

Nereida ignava gen. nov., sp. nov., a novel aerobic marine alpha-proteobacterium that is closely related to uncultured Prionitis (alga) gall symbiont…

2005

A Gram-negative, slightly halophilic, non-pigmented, strictly aerobic, chemo-organotrophic bacterium was isolated from Mediterranean sea water off the Spanish coast near Valencia. This strain was poorly reactive, being unable to grow in most carbon sources analysed in minimal medium. However, good growth was observed when more complex media and longer incubation times were used. Phylogenetic analysis based on an almost complete 16S rRNA gene sequence placed strain 2SM4T within the Roseobacter group, in the vicinity of uncultured bacteria described as gall symbionts of several species of the red alga Prionitis. Sequence similarity values between strain 2SM4T and the closest neighbouring spec…

Monochamus spp. un citu skujkoku saproksilo vaboļu (Coleoptera) sugu sabiedrības un to ievākšanas metodikas efektivitātes novērtējums kaitīgo organis…

2018

Kopš 1999. gadā Portugālē ieviesās priežu koksnes nematode Bursaphelenchus xylophilus, Eiropā Monochamus ģints koskngraužu nozīmība kā meža kaitēkļiem ievērojami pieauga, jo tie ir šīs nematodes galvenie vektori. B. xylophilus izraisa priežu vīti, kuras dēļ iet bojā liels koku daudzums. Latvijā nav pētīta Monochamus ģints sastopamība un feromonu lamatu efektivitāte, kas ir svarīga informācija, ja nākotnē būs vajadzība kontrolēt B. xylophilus riska zonās – teritorijās, kurās ir augstāka varbūtība kaitīgā organisma ieviešanās riskam. Darba mērķis ir noskaidrot Monochamus ģints koksngraužu sastopamību Latvijā riska zonu vietās un feromonu lamatu efektivitāti skujkoku saproksilo vaboļu ķeršanai…