29,270 research outputs found
Bringing nature back into cities: urban land environments, indigenous cover and urban restoration
1. The restoration of urban ecosystems is an increasingly important strategy to maintain and enhance indigenous biodiversity as well as reconnecting people to the environment. High levels of endemism, the sensitivity of species that have evolved without humans, and the invasion of exotic species have all contributed to severe depletion of indigenous biodiversity in New Zealand. In this work, we analysed national patterns of urban biodiversity in New Zealand and the contribution that urban restoration can make to maximising and enhancing indigenous biodiversity.
2. We analysed data from two national databases in relation to the 20 largest New Zealand cities. We quantified existing indigenous biodiversity within cities, both within the core built up matrix and in centroid buffer zones of 5, 10 and 20 km around this urban centre. We analysed the type and frequency of land environments underlying cities as indicators of the range of native ecosystems that are (or can potentially be) represented within the broader environmental profile of New Zealand. We identified acutely threatened land environments that are represented within urban and periurban areas and the potential role of cities in enhancing biodiversity from these land environments.
3. New Zealand cities are highly variable in both landform and level of indigenous resource. Thirteen of 20 major land environments in New Zealand are represented in cities, and nearly three-quarters of all acutely threatened land environments are represented within 20 km of city cores nationally. Indigenous land cover is low within urban cores, with less than 2% on average remaining, and fragmentation is high. However, indigenous cover increases to more than 10% on average in the periurban zone, and the size of indigenous remnants also increases. The number of remaining indigenous landcover types also increases from only 5 types within the urban centre, to 14 types within 20 km of the inner urban cores.
4. In New Zealand, ecosystem restoration alone is not enough to prevent biodiversity loss from urban environments, with remnant indigenous cover in the urban core too small (and currently too degraded) to support biodiversity long-term. For some cities, indigenous cover in the periurban zone is also extremely low. This has significant ramifications for the threatened lowland and coastal environments that are most commonly represented in cities. Reconstruction of ecosystems is required to achieve a target of 10% indigenous cover in cities: the addition of land to land banks for this purpose is crucial. Future planning that protects indigenous remnants within the periurban zone is critical to the survival of many species within urban areas, mitigating the homogenisation and depletion of indigenous flora and fauna typical of urbanisation. A national urban biodiversity plan would help city councils address biodiversity issues beyond a local and regional focus, while encouraging predominantly local solutions to restoration challenges, based on the highly variable land environments, ecosystems and patch connectivity present within different urban areas
Application of ribotyping and IS<i>200</i> fingerprinting to distinguish the five <i>Salmonella</i> serotype O6,7:c:1,5 groups: Choleraesuis <i>sensu stricto</i>, Choleraesuis var. Kunzendorf, Choleraesuis var. Decatur, Paratyphi C, and Typhisuis
Sixty-seven strains of the five described Salmonella serotypes having antigens 6,7:c: 1,5, that is
S. enterica serotype Choleraesuis sensu stricto, Choleraesuis var. Kunzendorf, Choleraesuis var.
Decatur, Paratyphi C, and Typhisuis, were examined for 16S rrn profile ribotype, presence of
IS200 and phenotypic characters, including rate of change of flagellar-antigen phase and
nutritional character. Choleraesuis sensu stricto and its Kunzendorf variant had related but
distinct ribotypes. Therefore, ribotyping appears to be a suitable method for differentiating
Choleraesuis non-Kunzendorf from Choleraesuis var. Kunzendorf. Some strains of Paratyphi C
had 16S profiles that resembled that of Choleraesuis non-Kunzendorf, while others resembled
that of Choleraesuis var. Kunzendorf. The Typhisuis profiles were like those of Choleraesuis
non-Kunzendorf, while the Choleraesuis var. Decatur profiles were unlike those of any of the
other four groups. Furthermore, IS200 fingerprinting discriminated between Choleraesuis var.
Decatur and the other strains with antigenic formula O6,7:c: 1,5, and comparison of IS200
patterns showed a high degree of genetic divergence within Choleraesuis var. Decatur. Our
findings show that ribotyping and IS200 fingerprinting, combined with classical microbiological
methods, distinguish the groups Choleraesuis non-Kunzendorf, Choleraesuis var. Kunzendorf,
Choleraesuis var. Decatur, Paratyphi C and Typhisuis
Counting (3+1) - Avoiding permutations
A poset is {\it (\3+\1)-free} if it contains no induced subposet isomorphic
to the disjoint union of a 3-element chain and a 1-element chain. These posets
are of interest because of their connection with interval orders and their
appearance in the (\3+\1)-free Conjecture of Stanley and Stembridge. The
dimension 2 posets are exactly the ones which have an associated
permutation where in if and only if as integers and
comes before in the one-line notation of . So we say that a
permutation is {\it (\3+\1)-free} or {\it (\3+\1)-avoiding} if its
poset is (\3+\1)-free. This is equivalent to avoiding the permutations
2341 and 4123 in the language of pattern avoidance. We give a complete
structural characterization of such permutations. This permits us to find their
generating function.Comment: 17 page
The Americans with Disabilities Act of 1990 and Injured Workers
This brochure is one of a series on human resources practices and workplace accommodations for persons with disabilities edited by Susanne M. Bruyère, Ph.D., CRC, Director, Employment and Disability Institute, Cornell University ILR School. This brochure was originally written in 1997 by Professor Bruce Growick, the Ohio State University, and reviewed and updated September, 2001 by Sheila D. Duston, an attorney- mediator practicing in the Washington, DC metropolitan area. It was reviewed and updated in 2011 by Elizabeth Reiter, an independent legal consultant in Ithaca, N.Y., with assistance from Sara Furguson, a Cornell University Employment and Disability Institute ILR student research assistant
Real, virtual, and other personas in an online collaborative environment
This presentation reports on a study of an unusual online course, which incorporates collaboration across campuses in teaching about evaluation of information technologies. Issues raised by new information technologies are major foci within the course, and also entry points for our study of its implementation.published or submitted for publicationis peer reviewe
Tensile film clamps and mounting block for the rheovibron and autovibron viscoelastometer
A set of film clamps and a mounting block for use in the determination of tensile modulus and damping properties of films in a manually operated or automated Rheovibron is diagrammed. These clamps and mounting block provide uniformity of sample gripping and alignment in the instrument. Operator dependence and data variability are greatly reduced
- …