647 research outputs found
Isolation of anaerobic, extremely thermophilic, sulphur metabolising archaebacteria from New Zealand hot springs
Enrichments of New Zealand geo-thermal samples, initiated in anaerobic sulphur-containing media and incubated at temperatures above 85°C, yielded rod and coccal shaped organisms which possessed archaebacterial characteristics. Pure cultures were isolated and characterised. Five of the seven isolates, which were rod-shaped organisms and did not have an obligate requirement for sulphur respiration, were similar to Ther-moproteus sp. but had more neutral pH optima for growth. Three of these five Thermoproteus sp. were obligate heterotrophs, which has not previously been reported. The two coccal isolates had an obligate requirement for sulphur as an electron acceptor and were similar to Desulfurococcus sp. but again with more neutral pH optima for growth
Bubbly Turbulent Drag Reduction Is a Boundary Layer Effect
In turbulent Taylor-Couette flow, the injection of bubbles reduces the overall drag. On the other hand, rough walls enhance the overall drag. In this work, we inject bubbles into turbulent Taylor-Couette flow with rough walls (with a Reynolds number up to 4Ă105), finding an enhancement of the dimensionless drag as compared to the case without bubbles. The dimensional drag is unchanged. As in the rough-wall case no smooth boundary layers can develop, the results demonstrate that bubbly drag reduction is a pure boundary layer effec
Characterization of the Polycomb-Group Mark H3K27me3 in Unicellular Algae
Polycomb Group (PcG) proteins mediate chromatin repression in plants and
animals by catalyzing H3K27 methylation and H2AK118/119 mono-ubiquitination
through the activity of the Polycomb repressive complex 2 (PRC2) and PRC1,
respectively. PcG proteins were extensively studied in higher plants, but
their function and target genes in unicellular branches of the green lineage
remain largely unknown. To shed light on PcG function and modus operandi in a
broad evolutionary context, we demonstrate phylogenetic relationship of core
PRC1 and PRC2 proteins and H3K27me3 biochemical presence in several
unicellular algae of different phylogenetic subclades. We focus then on one of
the species, the model red alga Cyanidioschizon merolae, and show that
H3K27me3 occupies both, genes and repetitive elements, and mediates the
strength of repression depending on the differential occupancy over gene
bodies. Furthermore, we report that H3K27me3 in C. merolae is enriched in
telomeric and subtelomeric regions of the chromosomes and has unique
preferential binding toward intein-containing genes involved in protein
splicing. Thus, our study gives important insight for Polycomb-mediated
repression in lower eukaryotes, uncovering a previously unknown link between
H3K27me3 targets and protein splicing
What is the prevalence, and what are the clinical correlates, of insulin resistance in young people presenting for mental health care? A cross-sectional study
Objectives: To report the distribution and predictors of insulin resistance (IR) in young people presenting to primary care-based mental health services.
Design: Cross-sectional.
Setting: Headspace-linked clinics operated by the Brain and Mind Centre of the University of Sydney.
Participants: 768 young people (66% female, mean age 19.7±3.5, range 12â30 years).
Main outcome measures: IR was estimated using the updated homeostatic model assessment (HOMA2-IR). Height and weight were collected from direct measurement or self-report for body mass index (BMI).
Results: For BMI, 20.6% of the cohort were overweight and 10.2% were obese. However,6.9 mmol/L). By contrast, 9.9% had a HOMA2-IR score \u3e2.0 (suggesting development of IR) and 11.7% (n=90) had a score between 1.5 and 2. Further, there was a positive correlation between BMI and HOMA2-IR (r=0.44, p
Conclusions: Emerging IR is evident in a significant subgroup of young people presenting to primary care based mental health services. While the major modifiable risk factor is BMI, a large proportion of the variance is not accounted for by other demographic, clinical or treatment factors. Given the early emergence of IR, secondary prevention interventions may need to commence prior to the development of full-threshold or major mood or psychotic disorders
The staggered domain wall fermion method
A different lattice fermion method is introduced. Staggered domain wall
fermions are defined in 2n+1 dimensions and describe 2^n flavors of light
lattice fermions with exact U(1) x U(1) chiral symmetry in 2n dimensions. As
the size of the extra dimension becomes large, 2^n chiral flavors with the same
chiral charge are expected to be localized on each boundary and the full
SU(2^n) x SU(2^n) flavor chiral symmetry is expected to be recovered. SDWF give
a different perspective into the inherent flavor mixing of lattice fermions and
by design present an advantage for numerical simulations of lattice QCD
thermodynamics. The chiral and topological index properties of the SDWF Dirac
operator are investigated. And, there is a surprise ending...Comment: revtex4, 7 figures, minor revisions, 2 references adde
Three principles for co-designing sustainability intervention strategies : Experiences from Southern Transylvania
Transformational research frameworks provide understanding and guidance for fostering change towards sustainability. They comprise stages of system understanding, visioning and co-designing intervention strategies to foster change. Guidance and empirical examples for how to facilitate the process of co-designing intervention strategies in real-world contexts remain scarce, especially with regard to integrating local initiatives. We suggest three principles to facilitate the process of co-designing intervention strategies that integrate local initiatives: (1) Explore existing and envisioned initiatives fostering change towards the desired future; (2) Frame the intervention strategy to bridge the gap between the present state and desired future state(s), building on, strengthening and complementing existing initiatives; (3) Identify drivers, barriers and potential leverage points for how to accelerate progress towards sustainability. We illustrate our approach via a case study on sustainable development in Southern Transylvania. We conclude that our principles were useful in the case study, especially with regards to integrating initiatives, and could also be applied in other real-world contexts.Peer reviewe
Water Resources Systems Planning and Management: An Introduction to Methods, Models and Applications
This 2005 version has been superseded by the 2017 edition, available in full here: http://hdl.handle.net/1813/48159Throughout history much of the world has witnessed
ever-greater demands for reliable, high-quality and
inexpensive water supplies for domestic consumption,
agriculture and industry. In recent decades there have
also been increasing demands for hydrological regimes
that support healthy and diverse ecosystems, provide for
water-based recreational activities, reduce if not prevent
floods and droughts, and in some cases, provide for the
production of hydropower and ensure water levels adequate
for ship navigation. Water managers are challenged
to meet these multiple and often conflicting demands. At
the same time, public stakeholder interest groups have
shown an increasing desire to take part in the water
resources development and management decision making
process. Added to all these management challenges
are the uncertainties of natural water supplies and
demands due to changes in our climate, changes in
people's standards of living, changes in watershed land
uses and changes in technology. How can managers
develop, or redevelop and restore, and then manage water
resources systems - systems ranging from small watersheds
to those encompassing large river basins and coastal
zones - in a way that meets society's changing objectives
and goals? In other words, how can water resources
systems become more integrated and sustainable
Relation between incidence of Fusarium graminearum in seeds, emergence and occurrence of giberela in wheat seedlings
Com o objetivo de verificar o comportamento de 30 genĂłtipos de trigo em relação Ă emergĂȘncia e Ă incidĂȘncia de giberela em plĂąntulas provenientes de sementes portadoras de Fusarium graminearum, foram instalados experimentos de laboratĂłrio e casa-de-vegetação. Em laboratĂłrio, as sementes utilizadas para os experimentos de emergĂȘncia e incidĂȘncia de giberela foram analisadas para sanidade pelo mĂ©todo do papel de filtro com congelamento. Em casa-de-vegetação, as sementes foram distribuĂdas em caixas de plĂĄstico, contendo areia tratada com brometo de metila. O delineamento utilizado foi o de blocos casualizados, constituĂdo de 30 tratamentos com quatro repetiçÔes de 50 sementes, perfazendo um total de 200 sementes/tratamento. As avaliaçÔes da emergĂȘncia de plĂąntulas e da incidĂȘncia de giberela foram feitas aos sete, 14 e 21 dias apĂłs a semeadura (DAS), contando-se o nĂșmero de plĂąntulas emergidas e retirando-se as plĂąntulas sintomĂĄticas, as quais foram submetidas a cĂąmara Ășmida, por 24 horas, em laboratĂłrio. NĂŁo houve diferença significativa da incidĂȘncia do patĂłgeno na emergĂȘncia das plĂąntulas. NĂŁo foi constatada correlação entre a incidĂȘncia de giberela nas plĂąntulas e o nĂvel de resistĂȘncia dos genĂłtipos, bem como entre incidĂȘncia de giberela nas plĂąntulas e a incidĂȘncia do patĂłgeno nas sementes.In order to verify the behavior of 30 genotypes of wheat in relation to the emergence and incidence of giberela in wheat seedlings from seeds contaminated with F. graminearum, experiments were carried out under laboratory and greenhouse conditions. In the laboratory, seeds were analyzed for health using freezer blotter test. In the greenhouse, seeds were sowed in plastic boxes filled with sand treated with methyl bromide. Statistical design was randomized blocks with 30 treatments, four replications of 50 seeds (200 seeds/treatment). Emergence of seedlings and giberela incidence were evaluated at seven, 14 and 21 days after sowing. Symptomatic seedlings were removed and submitted to humid chambers for 24 hours under laboratory conditions. There was no significant difference in the incidence of the pathogen in the emergence of seedlings. There was no correlation between the incidence of F. graminearum in the genotypes and incidence of giberela in seedlings, nor between the incidence of giberela in seedlings and the incidence of the pathogen in the seeds
Locally Perturbed Random Walks with Unbounded Jumps
In \cite{SzT}, D. Sz\'asz and A. Telcs have shown that for the diffusively
scaled, simple symmetric random walk, weak convergence to the Brownian motion
holds even in the case of local impurities if . The extension of their
result to finite range random walks is straightforward. Here, however, we are
interested in the situation when the random walk has unbounded range.
Concretely we generalize the statement of \cite{SzT} to unbounded random walks
whose jump distribution belongs to the domain of attraction of the normal law.
We do this first: for diffusively scaled random walks on having finite variance; and second: for random walks with distribution
belonging to the non-normal domain of attraction of the normal law. This result
can be applied to random walks with tail behavior analogous to that of the
infinite horizon Lorentz-process; these, in particular, have infinite variance,
and convergence to Brownian motion holds with the superdiffusive scaling.Comment: 16 page
Technical advances in near real time seafloor monitoring implemented for the momar-d project
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