56 research outputs found
Analysis and calibration of absorptive images of Bose-Einstein condensate at non-zero temperatures
We describe the method allowing quantitative interpretation of absorptive
images of mixtures of BEC and thermal atoms which reduces possible systematic
errors associated with evaluation of the contribution of each fraction. By
using known temperature dependence of the BEC fraction, the analysis allows
precise calibration of the fitting results. The developed method is verified in
two different measurements and compares well with theoretical calculations and
with measurements performed by another group.Comment: 17 pages, 8 figure
Repurposing a deep learning network to filter and classify volunteered photographs for land cover and land use characterization
This paper extends recent research into the usefulness of volunteered photos for land cover extraction, and investigates whether this usefulness can be automatically assessed by an easily accessible, off-the-shelf neural network pre-trained on a variety of scene characteristics. Geo-tagged photographs are sometimes presented to volunteers as part of a game which requires them to extract relevant facts about land use. The challenge is to select the most relevant photographs in order to most efficiently extract the useful information while maintaining the engagement and interests of volunteers. By repurposing an existing network which had been trained on an extensive library of potentially relevant features, we can quickly carry out initial assessments of the general value of this approach, pick out especially salient features, and identify focus areas for future neural network training and development. We compare two approaches to extract land cover information from the network: a simple post hoc weighting approach accessible to non-technical audiences and a more complex decision tree approach that involves training on domain-specific features of interest. Both approaches had reasonable success in characterizing human influence within a scene when identifying the land use types (as classified by Urban Atlas) present within a buffer around the photograph’s location. This work identifies important limitations and opportunities for using volunteered photographs as follows: (1) the false precision of a photograph’s location is less useful for identifying on-the-spot land cover than the information it can give on neighbouring combinations of land cover; (2) ground-acquired photographs, interpreted by a neural network, can supplement plan view imagery by identifying features which will never be discernible from above; (3) when dealing with contexts where there are very few exemplars of particular classes, an independent a posteriori weighting of existing scene attributes and categories can buffer against over-specificity
Quantification of habitat fragmentation reveals extinction risk in terrestrial mammals
Although habitat fragmentation is often assumed to be a primary driver of extinction, global patterns of fragmentation and its relationship to extinction risk have not been consistently quantified for any major animal taxon. We developed high-resolution habitat fragmentation models and used phylogenetic comparative methods to quantify the effects of habitat fragmentation on the world's terrestrial mammals, including 4,018 species across 26 taxonomic Orders. Results demonstrate that species with more fragmentation are at greater risk of extinction, even after accounting for the effects of key macroecological predictors, such as body size and geographic range size. Species with higher fragmentation had smaller ranges and a lower proportion of high-suitability habitat within their range, andmost high-suitability habitat occurred outside of protected areas, further elevating extinction risk. Our models provide a quantitative evaluation of extinction risk assessments for species, allow for identification of emerging threats in species not classified as threatened, and provide maps of global hotspots of fragmentation for the world's terrestrial mammals. Quantification of habitat fragmentation will help guide threat assessment and strategic priorities for global mammal conservation
Free-fall expansion of finite-temperature Bose-Einstein condensed gas in the non Thomas-Fermi regime
We report on our study of the free-fall expansion of a finite-temperature
Bose-Einstein condensed cloud of 87Rb. The experiments are performed with a
variable total number of atoms while keeping constant the number of atoms in
the condensate. The results provide evidence that the BEC dynamics depends on
the interaction with thermal fraction. In particular, they provide experimental
evidence that thermal cloud compresses the condensate.Comment: 8 pages, 4 figure
Where are commodity crops certified, and what does it mean for conservation and poverty alleviation?
Voluntary sustainability standards have expanded dramatically over the last decade. In the agricultural sector, such standards aim to ensure environmentally and socially sustainable production of a variety of commodity crops. However, little is known about where agricultural certification operates and whether certified lands are best located for conserving the world's most important biodiversity and benefiting the most vulnerable producers. To examine these questions we developed the first global map of commodity crop certification, synthesizing data from over one million farms to reveal the distribution of certification in unprecedented detail. It highlights both geographical clusters of certification as well as spatial bias in the location of certification with respect to environmental, livelihood and physical variables. Excluding organic certification, for which spatial data were not available, most certification of commodity crops is in tropical regions. Certification appears to be concentrated in areas important for biodiversity conservation, but not in those areas most in need of poverty alleviation, although there were exceptions to each of these patterns. We argue that the impact of sustainability standards could be increased by identifying places where it would be most beneficial to strengthen, consolidate, and expand certification. To achieve this, standards organizations will need to undertake more rigorous collection of spatial data, and more detailed analysis of their existing reach and impacts, with attention to potential trade-offs between different objectives. Efforts to promote spatial prioritization will require new partnerships to align specific conservation aims with the interests and capabilities of farmers
Gone with the forest: Assessing global woodpecker conservation from land use patterns
As a result of their ecological traits, woodpeckers (Picidae, Aves) are highly sensitive to forest cover change. We explored the current land cover in areas of high species richness of woodpeckers to determinate regions where urgent conservation actions are needed. In addition, we identified woodpecker species that are sensitive to forest loss and that have high levels of human habitat modification and low levels of protection (through protected areas) in their distribution ranges. Location: Global. Methods: We joined available range maps for all extant 254 woodpecker species with information of their conservation status and tolerances to human habitat modifications and generated a richness map of woodpecker species worldwide. Then, we associated this information (the richness pattern and individual species’ maps) with land cover and protected areas (PAs) maps. We found that the foremost woodpecker species richness hotspot is in Southeast Asia and is highly modified. At the second species richness hotspot in the eastern Andes, we observed a front of deforestation at its southern extreme and a greater deforested area in its northern extreme but most of its area remains with forest coverage. At the species level, 17 species that are sensitive to forest modification experience extensive deforestation and have low extents of PAs in their ranges.The most diverse woodpecker hotspots are mostly occupied by human-modified landscapes, and a large portion of the species there avoids anthropogenic environments. The level of representation of woodpecker species in PAs is low as a global general pattern, although slightly better in Asia. Our global analysis of threats to woodpecker from land use patterns reiterates the urgent conservation needs for Southeast Asian forests. Finally, based on our results, we recommend a re-evaluation for inclusion in the Red List of five woodpecker species.Fil: Vergara Tabares, David Lautaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; ArgentinaFil: Lammertink, J. Martjan. Cornell University; Estados Unidos. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Verga, Ernesto Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Schaaf, Alejandro Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Jujuy. Universidad Nacional de Jujuy. Centro de Investigaciones y Transferencia de Jujuy; ArgentinaFil: Nori, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentin
Rapid and Repeatable Shifts in Life-History Timing of \u3ci\u3eRhagoletis pomonella\u3c/i\u3e (Diptera: Tephritidae) Following Colonization of Novel Host Plants in the Pacific Northwestern United States
Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonellafruit flies in eastern North America underwent a host shift ~160 ya from native downy hawthorn (Crataegus mollis) to introduced, domesticated apple (Malus domestica). Divergent selection on diapause phenology related to the earlier fruiting time of apples versus downy hawthorns resulted in partial allochronic reproductive isolation between the fly races. Here, we test for how rapid and repeatable shifts in life-history timing are driving ecological divergence of R. pomonella in the Pacific Northwestern USA. The fly was introduced into the region via larval-infested apples 40–65 ya and now attacks native black hawthorn (Crataegus douglasii) and introduced ornamental hawthorn (Crataegus monogyna), in addition to early- and late-maturing apple varieties in the region. To investigate the life-history timing hypothesis, we used a field-based experiment to characterize the host-associated eclosion and flight activity patterns of adults, and the feeding times of larvae at a field site in Vancouver, Washington. We also assessed the degree to which differences in host-fruiting time generate allochronic isolation among apple-, black hawthorn-, and ornamental hawthorn-associated fly populations. We conclude that host-associated fly populations are temporally offset 24.4% to 92.6% in their seasonal distributions. Our results imply that R. pomonella possesses the capacity for rapid and repeatable shifts in diapause life history to match host-fruiting phenology, which can generate ecologically based reproductive isolation, and potentially biodiversity in the process
Toward quantification of the impact of 21st-century deforestation on the extinction risk of terrestrial vertebrates
Conservation actions need to be prioritized, often taking into account species’ extinction risk. The International Union for Conservation of Nature (IUCN) Red List provides an accepted, objective framework for the assessment of extinction risk. Assessments based on data collected in the field are the best option, but the field data to base these on are often limited. Information collected through remote sensing can be used in place of field data to inform assessments. Forests are perhaps the best-studied land-cover type for use of remote-sensing data. Using an open-access 30-m resolution map of tree cover and its change between 2000 and 2012, we assessed the extent of forest cover and loss within the distributions of 11,186 forest-dependent amphibians, birds, and mammals worldwide. For 16 species, forest loss resulted in an elevated extinction risk under red-list criterion A, owing to inferred rapid population declines. This number increased to 23 when data-deficient species (i.e., those with insufficient information for evaluation) were included. Under red-list criterion B2, 484 species (855 when data-deficient species were included) were considered at elevated extinction risk, owing to restricted areas of occupancy resulting from little forest cover remaining within their ranges. The proportion of species of conservation concern would increase by 32.8% for amphibians, 15.1% for birds, and 24.7% for mammals if our suggested uplistings are accepted. Central America, the Northern Andes, Madagascar, the Eastern Arc forests in Africa, and the islands of Southeast Asia are hotspots for these species. Our results illustrate the utility of satellite imagery for global extinction-risk assessment and measurement of progress toward international environmental agreement targets
The relationship between transformational leadership and leadership effectiveness during organizational change
Today’s business environment for organizations is highly challenging to cope with and complex organizational changes are ever-present as organizations need to evolve constantly. To be able to succeed in implementing a transformational organizational change a high level of leadership capabilities is required where transformational leaders and overall leadership effectiveness can enhance the chances for organization to succeed in change implementation. The purpose of this research was to study what is the relationship between transformational leadership and leadership effectiveness during transformational organizational change and how they can effect the outcome of the change implementation.
This research was conducted by applying a single case study with in-depth interviews by interviewing employees from organizations which were going or have gone through a transformational organizational change by evaluating their leader’s characteristics, effectiveness and performance during transformational organizational change. Organizations chosen for this research needed to fill the criterion that they were going or have gone through a transformational organizational change. Organizations chosen for this research were different by size, industry and the degree of internationality.
Based on the findings from the empirical research a clear connection was discovered between transformational leadership, high level of leadership effectiveness and successful outcome of change implementation. It was also discovered that open and clear communication, the leader’s own positive attitude towards the change and low level of hierarchy in organizations had a particularly positive effect for successful change implementation during transformational organizational change.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format
Ympäristösuunnitelman laatiminen GCE Service oy:lle
Opinnäytetyön tarkoituksena oli laatia GCE Service Oy:lle ympäristösuunnitelma, jota voitaisiin hyödyntää kilpailutuksissa ja sidosryhmäviestinnässä. Yrityksen toiminta on keskittynyt maansiirtokoneiden korjaamiseen. Tarkoituksena oli keskityttyä alkukartoituksen perusteella suunnitelmassa niihin ympäristövaikutuksiin, joihin yrityksen toiminnalla on eniten vaikutusta ja esittää mahdollisia kehitysehdotuksia.
Opinnäytetyössä käytiin läpi ympäristöjärjestelmiä, yritysvastuuta ja yrityksen toimialaa koskevaa lainsäädäntöä, jolla on vaikutusta yrityksen toimintaan ja ympäristösuunnitelman laatimiseen. Yritykselle laadittiin ympäristösuunnitelma ja kehityskohteiden seuraamiseksi laadittiin toimenpidelistaus, jonka avulla voidaan seurata ympäristötavoitteiden toteutumista.
Ympäristösuunnitelman laatiminen vaatii resursseja ja osaamista, jota monella pienellä yrityksellä ei ole. Toteutuksella voidaan saada hyötyjä, joilla on positiivisia vaikutuksia yrityksen toimintaan. Suunnitelman avulla voidaan vähentää yrityksen vaikutuksia ympäristöön, mutta saada aikaan myös kustannussäästöjä, hallita riskejä sekä edistää yrityksen kilpailukykyä
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