539 research outputs found
The status of storks, ibises and spoonbills in Indonesia
A brief summary is given of the current status in Indonesia of the eleven Stork, Ibis and Spoonbill species occurring in Indonesia. Of these the Storm's Stork, Royal Spoonbill, and White-shouldered Ibis are considered as endangered and likely to disappear in Indonesia within the next decades if no conservation action is undertaken. Ongoing conservation programmes for the species are discussed and additional conservation measures outlined
Context Aware Routing Management Architecture for Airborne Networks
Military environments require highly dynamic mobile ad hoc networks (MANETs) to meet operational mission requirements. Decision makers rely on the timely delivery of critical battlefield information to make informed determinations quickly and as accurately as possible. However, traditional MANET routing protocols do not provide quality of service (QoS). Furthermore, they do not implement active controls to minimise the impact of network congestion. This study proposes the use of the information embedded in an air tasking order (ATO) during the planning phase of military missions to optimise the network performance. The trajectories of relevant nodes (airborne platforms) participating in the MANET can be forecasted by parsing key information contained in the ATO. Using this idea it is possible to optimise network routes to minimise edge overutilisation and increase network throughput. In onesimulated test case, there was a 25% improvement of network throughput, and 23% reduction on dropped packets. Using this technique, the authors can selectively preserve the QoS by establishing network controls that drop low-priority packets when necessary. The algorithm improves the overall MANET throughput while minimising the packets dropped due to network congestion
Considering sustainability in project management decision making; an investigation using Q-methodology
Abstract: Sustainability is one of the most important challenges of our time. Projects play a pivotal role in the realization of more sustainable business practices and the concept of sustainability has also been linked to project management. However, how managers of projects consider sustainability in their operational daily work is still to be explored. This paper uses Q-methodology to investigate the consideration of sustainability aspects in the decision making processes of project managers. The research question was How are dimensions of sustainability considered in the decision-making processes of project managers in relation to the triple constraint of time, cost and quality? Based on the Q-sort of selected respondents, the study found that the consideration of sustainability principles is underrepresented, compared to the triple constraint criteria. However, the analysis of the individual Q-sorts revealed four distinct perspectives that differ significantly in their consideration of sustainability principles and triple constraint criteria
Insertion of an uncharged polypeptide into the mitochondrial inner membrane does not require a trans-bilayer electrochemical potential: effects of positive charges
AbstractMitochondria with a ruptured outer membrane exhibited impaired import into this membrane of an outer membrane fusion protein containing the signal-anchor sequence of Mas70p. However, the Mas70p signal-anchor efficiently targeted and inserted the protein directly into exposed regions of the inner membrane. Import into the inner membrane was dependent on Î´Ď and this dependence was due to the presence of the positively-charged amino acids located at positions 2, 7, and 9 of the signal-anchor. In contrast to wild-type signal-anchor, mutants lacking the positively-charged residues mediated import into the inner membrane in both the presence and absence of δĎ. The results suggest two conclusions: (1) δĎ-dependent import of the signal-anchor sequence was due exclusively to an effect of Î´Ď on the positively-charged domain of the signal-anchor, rather than to an effect of Î´Ď on a property of the inner membrane import machinery; (2) in the absence of δĎ, the positively-charged domain of the signal-anchor prevented the otherwise import-competent signal-anchor from inserting into the membrane. This suggests that the positively-charged domain leads import across the inner membrane, and that dqi is required to vectorially clear this domain in order to allow the distal region of the signal-anchor to enter the translocation pathway. The implications of these findings on the mechanism of import into the mitochondrial inner membrane and matrix are discussed
Adiabatic-Nonadiabatic Transition in the Diffusive Hamiltonian Dynamics of a Classical Holstein Polaron
We study the Hamiltonian dynamics of a free particle injected onto a chain
containing a periodic array of harmonic oscillators in thermal equilibrium. The
particle interacts locally with each oscillator, with an interaction that is
linear in the oscillator coordinate and independent of the particle's position
when it is within a finite interaction range. At long times the particle
exhibits diffusive motion, with an ensemble averaged mean-squared displacement
that is linear in time. The diffusion constant at high temperatures follows a
power law D ~ T^{5/2} for all parameter values studied. At low temperatures
particle motion changes to a hopping process in which the particle is bound for
considerable periods of time to a single oscillator before it is able to escape
and explore the rest of the chain. A different power law, D ~ T^{3/4}, emerges
in this limit. A thermal distribution of particles exhibits thermally activated
diffusion at low temperatures as a result of classically self-trapped polaronic
states.Comment: 15 pages, 4 figures Submitted to Physical Review
Mammal traits and soil biogeochemistry: Functional diversity relates to composition of soil organic matter
Mammal diversity affects carbon concentration in Amazonian soils. It is known that some species traits determine carbon accumulation in organisms (e.g., size and longevity), and are also related to feeding strategies, thus linking species traits to the type of organic remains that are incorporated into the soil. Trait diversity in mammal assemblages â that is, its functional diversity â may therefore constitute another mechanism linking biodiversity to soil organic matter (SOM) accumulation. To address this hypothesis, we analyzed across 83 mammal assemblages in the Amazon biome (Guyana), the elemental (by EDâXRF and CNH analysis) and molecular (FTIRâATR) composition of SOM of topsoils (401 samples) and trait diversity (functional richness, evenness, and divergence) for each mammal assemblage. Lower mammal functional richness but higher functional divergence were related to higher content of carbonyl and aliphatic SOM, potentially affecting SOM recalcitrance. Our results might allow the design of biodiversity management plans that consider the effect of mammal traits on carbon sequestration and accumulation in soils.Xunta de Galicia | Ref. ED431C 2021/32Xunta de Galicia | Ref. ED481D 2019/024National Science Foundation | Ref. BE/CNH 05 0809
Mammal and tree diversity accumulate different types of soil organic matter in the northern Amazon
Diversity of plants and animals influence soil carbon through their contributions
to soil organic matter (SOM). However, we do not know whether mammal and
tree communities affect SOM composition in the same manner. This question is
relevant because not all forms of carbon are equally resistant to mineralization
by microbes and thus, relevant to carbon storage. We analyzed the elemental
and molecular composition of 401 soil samples, with relation to the species richness
of 83 mammal and tree communities at a landscape scale across 4.8 million
hectares in the northern Amazon. We found opposite effects of mammal and
tree richness over SOM composition. Mammal diversity is related to SOM rich
in nitrogen, sulfur and iron whereas tree diversity is related to SOM rich in
aliphatic and carbonyl compounds. These results help us to better understand
the role of biodiversity in the carbon cycle and its implications for climate change
mitigation.Xunta de Galicia | ED481D 2019/024Xunta de Galicia | ED431C2021/32European Commission | Ref. H2020, n. 947921National Science Foundation (NSF) | BE/CNH 05 0809
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