2,133 research outputs found
Line shifts in the first overtone of DF broadened by HF
Line spectra shifts in HF and in first overtone band of DF induced by HF pressure
Molecular interaction of the gamma-clade homeodomain-leucine zipper class I transcription factors during the wheat response to water deficit
The ᵧ-clade of class I homeodomain-leucine zipper (HD-Zip I) transcription factors (TFs) constitute members which play a role in adapting plant growth to conditions of water deficit. Given the importance of wheat (Triticum aestivum L.) as a global food crop and the impact of water deficit upon grain yield, we focused on functional aspects of wheat drought responsive HD-Zip I TFs. While the wheat ᵧ-clade HD-Zip I TFs share significant sequence similarities with homologous genes from other plants, the clade-specific features in transcriptional response to abiotic stress were detected. We demonstrate that wheat TaHDZipI- 3, TaHDZipI-4, and TaHDZipI-5 genes respond differentially to a variety of abiotic stresses, and that proteins encoded by these genes exhibit pronounced differences in oligomerisation, strength of DNA binding, and trans-activation of an artificial promoter. Three-dimensional molecular modelling of the protein-DNA interface was conducted to address the ambiguity at the central nucleotide in the pseudo-palindromic cis-element CAATNATTG that is recognised by all three HD-Zip I proteins. The coexpression of these genes in the same plant tissues together with the ability of HD-Zip I TFs of the ᵧ -clade to heterodimerise suggests a role in the regulatory mechanisms of HD-Zip I dependent transcription. Our findings highlight the complexity of TF networks involved in plant responses to water deficit. A better understanding of the molecular complexity at the protein level during crop responses to drought will enable adoption of efficient strategies for production of cereal plants with enhanced drought tolerance.John C. Harris, Pradeep Sornaraj, Mathew Taylor, Natalia Bazanova, Ute Baumann, Ben Lovell, Peter Langridge, Sergiy Lopato, Maria Hrmov
Beyond Measure? The State of Evaluation and Action in Ontario’s Youth Sector.
Program evaluation has the potential to inform and improve youth work practice, as well as help youth sector organizations and initiatives to better understand the impact of their work. This report presents findings from the first province-wide study of the Ontario youth sector’s experiences conducting evaluations of their programs and services.
This multi-focal study, led by Ontario’s Youth Research and Evaluation eXchange (YouthREX), used a Community Dialogue Approach. Grounded in an extensive literature review and drawing on survey and interview data, the report puts forward ten key recommendations for three youth sector stakeholder groups: funders, evaluation capacity builders, and youth sector organizations.
The study’s contextualized examination of the youth sector’s evaluation strengths, informs YouthREX’s service delivery strategy, and contributes to critical conversations around evaluation related challenges and opportunities in the youth sector context.
To learn more and access additional resources from the report, check out the YouthREX website
The TANAMI Program
TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond
Interferometry) is a monitoring program to study the parsec-scale structures
and dynamics of relativistic jets in active galactic nuclei (AGN) of the
Southern Hemisphere with the Long Baseline Array and associated telescopes.
Extragalactic jets south of -30 degrees declination are observed at 8.4 GHz and
22 GHz every two months at milliarcsecond resolution. The initial TANAMI sample
is a hybrid radio and gamma-ray selected sample since the combination of VLBI
and gamma-ray observations is crucial to understand the broadband emission
characteristics of AGN.Comment: Confernce Proceedings for "X-ray Astronomy 2009" (Bologna), 3 pages,
3 figures, needs cls-fil
Dual-frequency VLBI study of Centaurus A on sub-parsec scales
Centaurus A is the closest active galactic nucleus. High resolution imaging
using Very Long Baseline Interferometry (VLBI) enables us to study the spectral
and kinematic behavior of the radio jet-counterjet system on sub-parsec scales,
providing essential information for jet emission and formation models. Our aim
is to study the structure and spectral shape of the emission from the
central-parsec region of Cen A. As a target of the Southern Hemisphere VLBI
monitoring program TANAMI (Tracking Active Galactic Nuclei with Milliarcsecond
Interferometry), VLBI observations of Cen A are made regularly at 8.4 and 22.3
GHz with the Australian Long Baseline Array (LBA) and associated telescopes in
Antarctica, Chile, and South Africa. The first dual-frequency images of this
source are presented along with the resulting spectral index map. An angular
resolution of 0.4 mas x 0.7 mas is achieved at 8.4 GHz, corresponding to a
linear scale of less than 0.013 pc. Hence, we obtain the highest resolution
VLBI image of Cen A, comparable to previous space-VLBI observations. By
combining with the 22.3 GHz image, which has been taken without contributing
transoceanic baselines at somewhat lower resolution, we present the
corresponding dual-frequency spectral index distribution along the sub-parsec
scale jet revealing the putative emission regions for recently detected
gamma-rays from the core region by Fermi/LAT. We resolve the innermost
structure of the milliarcsecond scale jet and counterjet system of Cen A into
discrete components. The simultaneous observations at two frequencies provide
the highest resolved spectral index map of an AGN jet allowing us to identify
multiple possible sites as the origin of the high energy emission.Comment: 5 pages, 3 figures (1 color); A&A, accepte
TANAMI - Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry
We present a summary of the observation strategy of TANAMI (Tracking Active
Galactic Nuclei with Austral Milliarcsecond Interferometry), a monitoring
program to study the parsec-scale structure and dynamics of relativistic jets
in active galactic nuclei (AGN) of the Southern Hemisphere with the Australian
Long Baseline Array (LBA) and the trans-oceanic antennas Hartebeesthoek, TIGO,
and O'Higgins. TANAMI is focusing on extragalactic sources south of -30 degrees
declination with observations at 8.4 GHz and 22 GHz every ~2 months at
milliarcsecond resolution. The initial TANAMI sample of 43 sources has been
defined before the launch of the Fermi Gamma Ray Space Telescope to include the
most promising candidates for bright gamma-ray emission to be detected with its
Large Area Telescope (LAT). Since November 2008, we have been adding new
sources to the sample, which now includes all known radio- and gamma-ray bright
AGN of the Southern Hemisphere. The combination of VLBI and gamma-ray
observations is crucial to understand the broadband emission characteristics of
AGN and the nature of relativistic jets.Comment: Conference proceedings "2009 Fermi Symposium" eConf Proceedings
C09112
A Tailored Approach: A model for literature searching in complex systematic reviews
doi: 10.1177/01655515221114452Our previous work identified that nine leading guidance documents for seven different types of systematic review advocated the same process of literature searching. We defined and illustrated this process and we named it ?the Conventional Approach?. The Conventional Approach appears to meet the needs of researchers undertaking literature searches for systematic reviews of clinical interventions. In this article, we report a new and alternate process model of literature searching called ?A Tailored Approach?. A Tailored Approach is indicated as a search process for complex reviews which do not focus on the evaluation of clinical interventions. The aims of this article are to (1) explain the rationale for, and the theories behind, the design of A Tailored Approach; (2) report the current conceptual illustration of A Tailored Approach and to describe a user?s interaction with the process model; and (3) situate the elements novel to A Tailored Approach (when compared with the Conventional Approach) in the relevant literature. A Tailored Approach suggests investing time at the start of a review, to develop the information needs from the research objectives, and to tailor the search approach to studies or data. Tailored Approaches should be led by the information specialist (librarian) but developed by the research team. The aim is not necessarily to focus on comprehensive retrieval. Further research is indicated to evaluate the use of supplementary search methods, methods of team-working to define search approaches, and to evaluate the use of conceptual models of information retrieval for testing and evaluation
Formyltetrahydrofolate Synthetase Gene Diversity in the Guts of Higher Termites with Different Diets and Lifestyles
In this study, we examine gene diversity for formyl-tetrahydrofolate synthetase (FTHFS), a key enzyme in homoacetogenesis, recovered from the gut microbiota of six species of higher termites. The "higher" termites (family Termitidae), which represent the majority of extant termite species and genera, engage in a broader diversity of feeding and nesting styles than the "lower" termites. Previous studies of termite gut homoacetogenesis have focused on wood-feeding lower termites, from which the preponderance of FTHFS sequences recovered were related to those from acetogenic treponemes. While sequences belonging to this group were present in the guts of all six higher termites examined, treponeme-like FTHFS sequences represented the majority of recovered sequences in only two species (a wood-feeding Nasutitermes sp. and a palm-feeding Microcerotermes sp.). The remaining four termite species analyzed (a Gnathamitermes sp. and two Amitermes spp. that were recovered from subterranean nests with indeterminate feeding strategies and a litter-feeding Rhynchotermes sp.) yielded novel FTHFS clades not observed in lower termites. These termites yielded two distinct clusters of probable purinolytic Firmicutes and a large group of potential homoacetogens related to sequences previously recovered from the guts of omnivorous cockroaches. These findings suggest that the gut environments of different higher termite species may select for different groups of homoacetogens, with some species hosting treponeme-dominated homoacetogen populations similar to those of wood-feeding, lower termites while others host Firmicutes-dominated communities more similar to those of omnivorous cockroaches
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