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Accessible Areas (accessible + area)
Selected AbstractsImpact of land use changes on mountain vegetationAPPLIED VEGETATION SCIENCE, Issue 2 2002Erich Tasser Abstract. In this study the impact of land use changes on vegetation in the sub-alpine-alpine belt is analysed. The study sites (4.7 km2) are located in the Passeier Valley (South Tyrol, Italy), at an elevation of 1500,2300 m a.s.l. The whole study area was used for hay-making ca. 60 yr ago. Today, part of the meadows are more intensively used, while other parts have been converted to pasture or have been abandoned. We analysed the reasons for these land use changes and the effects on vegetation with a Geographical Information System and geostatistical analysis. The result of these analyses are: (1) Current land use is mainly controlled by the degree of accessibility for vehicles. Accessible areas are being used more and more intensively, while poorly accessible areas are being abandoned or used as pasture. (2) Current vegetation is highly determined by current land use. Particular vegetation units can be assigned to each form of land use. (3) Succession starts immediately after abandonment. Depending on altitude, succession proceeds at different speeds and with different numbers of stages. Hence the type of vegetation indicates the time passed since abandonment. (4) Land use changes lead to characteristic changes in vegetation; they are considered to be the most important driving force for vegetation change. (5) Measures of intensification and abandonment of extensively used areas both lead to a decrease in the number of species. [source] Optimized damage detection of steel plates from noisy impact testINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 7 2006G. Rus Abstract Model-based non-destructive evaluation proceeds measuring the response after an excitation on an accessible area of the structure. The basis for processing this information has been established in recent years as an iterative scheme that minimizes the discrepancy between this experimental measurement and sequence of measurement trials predicted by a numerical model. The unknown damage that minimizes this discrepancy by means of a cost functional is to be found. The damage location and size is quantified and sought by means of a well-conditioned parametrization. The design of the magnitude to measure, its filtering for reducing noise effects and calibration, as well as the design of the cost functional and parametrization, determines the robustness of the search to combat noise and other uncertainty factors. These are key open issues to improve the sensitivity and identifiability during the information processing. Among them, a filter for the cost functional is proposed in this study for maximal sensitivity to the damage detection of steel plate under the impact loading. This filter is designed by means of a wavelet decomposition together with a selection of the measuring points, and the optimization criterion is built on an estimate of the probability of detection, using genetic algorithms. Numerical examples show that the use of the optimal filter allows to find damage of a magnitude several times smaller. Copyright © 2006 John Wiley & Sons, Ltd. [source] Sediment sequences and paleosols in the Kyichu Valley, southern Tibet (China), indicating Late Quaternary environmental changesISLAND ARC, Issue 3 2009Knut Kaiser Abstract The Tibetan Plateau is highly sensitive to environmental changes and affects the settings of a far larger territory in Central Asia and beyond. Thus, knowledge on past environmental changes in that area is essential. Even though the Kyichu (Lhasa River) Valley and its tributaries is an easily accessible area, the Late Quaternary landscape evolution of southern Tibet is in general scarcely known. Therefore, 12 sedimentary sections in the middle and lower catchment were subjected to multidisciplinary analyses (sedimentology, paleopedology, AMS 14C and luminescence dating, and charcoal determination) aiming at results on regional paleoenvironmental changes. At the altitude studied (3600,4000 m above sealevel), no glacial relics could be detected, indicating that the valley positions have been unglaciated since the Last Interglacial. The lack of fluvial,lacustrine structures above the floodplain is due to the aggradational character of this tectonically (sub-)active valley, which caused an alluvial burying of older valley bottoms. During the Late Pleistocene the mouth area of the Kyichu was occupied by a lake which was part of a larger dam-lake in the superordinate Yarlung Zhangbo Valley. On the valley flanks, loesses were predominantly deposited before the Last Glacial Maximum (LGM), whereas eolian sands were predominantly deposited around and after the LGM. Paleosols of Last Interglacial, Last Glacial and Holocene ages regularly occur at terrestrial sites representing temperate to cool and humid to semiarid conditions during soil formation. Ages of colluvial sediments indicate that the widespread barren valley slopes were primarily formed by Late Pleistocene erosion followed by a secondary Holocene erosion phase. Charcoal spectra indicate a Late Holocene change from a forest environment to a pastoral environment with sparse grasses, herbs and dwarf shrubs. It is assumed that the Late Holocene environmental changes, such as loss of forests/woodlands and erosion, have at least been reinforced by humans, enhancing a regional climatic aridification and cooling trend. [source] Methylene as a possible universal footprinting reagent that will include hydrophobic surface areas: Overview and feasibility: Properties of diazirine as a precursorPROTEIN SCIENCE, Issue 12 2000Frederic M. Richards Abstract Methylene is one of, if not the, most reactive organic chemical known. It has a very low specificity, which makes it essentially useless for synthesis, but suggests a possible role in protein footprinting with special importance in labeling solvent accessible nonpolar areas, identifying ligand binding sites, and outlining interaction areas on protomers that form homo or hetero oligomers in cellular assemblies. The singlet species is easily and conveniently formed by photolysis of diazirine. The reactions of interest are insertion into C-H bonds and addition to multiple bonds, both forming strong covalent bonds and stable compounds. Reaction with proteins and peptides is reported even in aqueous solutions where the vast majority of the reagent is used up in forming methanol. Species containing up to 5 to 10 extra : CH2 groups are easily detected by electrospray mass spectroscopy. In a mixture of a 14 Kd protein and a noninteracting 1.7 Kd peptide, the distribution of mass peaks in the electrospray spectra was close to that expected from random modification of the estimated solvent accessible area for the two molecules. For analysis at the single residue level, quantitation at labeling levels of one 13CH2 group per 10 to 20 kDa of protein appears to be possible with isotope ratio mass spectroscopy. In the absence of reactive solvents, photolysis of diazirine produces oily polymeric species that contain one or two nitrogen atoms, but not more, and are water soluble. [source] Innovation and Peripherality: An Empirical Comparative Study of SMEs in Six European Union Member CountriesECONOMIC GEOGRAPHY, Issue 1 2008Andrew Copus Abstract This article examines the rates of innovative activity of small and medium-sized enterprises (SMEs) in central areas and equally developed but less accessible areas in six European Union member states. The probability of innovating is well predicted by the observable characteristics of firms, entrepreneurial characteristics, and business networks. More accessible areas consistently present higher rates of innovative activity than do their peripheral counterparts. The difference in the rates of peripheral and central areas is decomposed into observable and non-observable factors. The entire innovation gap is attributed to nonobservable factors that constitute a combination of behavior and environment. Innovation policy for SMEs should aim to meet businesses' specific needs (firm-specific factors) and to sustain and improve the innovative environment. [source] Can late summer Landsat data be used for locating Asian migratory locust, Locusta migratoria migratoria, oviposition sites in the Amudarya River delta, Uzbekistan?ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2008Ramesh Sivanpillai Abstract Existing survey methods for assessing the Asian migratory locust, Locusta migratoria migratoria L. (Orthoptera: Acrididae), infestation risk in the Amudarya River delta, Uzbekistan, are largely constrained by economic resources and site accessibility. The surveys are restricted to a few easily accessible areas, which leads to a misinterpretation of the threat of locust infestation. This often results in indiscriminate blanket treatments of vast areas of wetlands with broad-spectrum insecticides, which may adversely impact non-target fauna and flora. In order to minimize the bias during surveys, one approach would be to allocate the sampling locations based on the distribution of the primary food and shelter plant of the locusts, the common reed, Phragmites australis (Cav.) Trin. ex Steud (Poaceae). In this study, we evaluated the utility of satellite-based remotely sensed data (Landsat TM) acquired in August 2006 to characterize reed distribution in the delta and identify potential locust oviposition sites. The overall accuracy of the Landsat data to map land cover classes in the delta was 84%. The Landsat TM data identified 90% of the reeds, but it was less useful in identifying areas where other vegetations (shrubs and grasses) were mixed with reeds. During the following summer field survey in June 2007, we identified 37 sites that were infested with early-instar locusts. The low migration capacity of young nymphs in dense reed vegetation allowed us to presume that these sites were used for oviposition in the previous summer. Twenty-eight (74%) of these 37 sites had reeds in the previous year. Results from these studies demonstrate that reed distribution maps derived from satellite data could be used for targeting locust egg-pod survey locations, in order to minimize sampling bias while predicting locust infestation risks for the following season. [source] Impact of land use changes on mountain vegetationAPPLIED VEGETATION SCIENCE, Issue 2 2002Erich Tasser Abstract. In this study the impact of land use changes on vegetation in the sub-alpine-alpine belt is analysed. The study sites (4.7 km2) are located in the Passeier Valley (South Tyrol, Italy), at an elevation of 1500,2300 m a.s.l. The whole study area was used for hay-making ca. 60 yr ago. Today, part of the meadows are more intensively used, while other parts have been converted to pasture or have been abandoned. We analysed the reasons for these land use changes and the effects on vegetation with a Geographical Information System and geostatistical analysis. The result of these analyses are: (1) Current land use is mainly controlled by the degree of accessibility for vehicles. Accessible areas are being used more and more intensively, while poorly accessible areas are being abandoned or used as pasture. (2) Current vegetation is highly determined by current land use. Particular vegetation units can be assigned to each form of land use. (3) Succession starts immediately after abandonment. Depending on altitude, succession proceeds at different speeds and with different numbers of stages. Hence the type of vegetation indicates the time passed since abandonment. (4) Land use changes lead to characteristic changes in vegetation; they are considered to be the most important driving force for vegetation change. (5) Measures of intensification and abandonment of extensively used areas both lead to a decrease in the number of species. [source] Balancing absolute and relative risk reduction in tobacco control policy: the example of antenatal smoking in Victoria, AustraliaAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2010Nathan Grills Abstract Objective: This descriptive epidemiological analysis aims to explore the benefits, risks and policy balance between a whole-of-population and high-risk reduction approach to reducing antenatal smoking prevalence. Methods: Using Victorian hospital antenatal statistics the rate-ratio for smoking in each hypothesised high prevalence group was calculated and combined with the absolute number of births in each high-risk group. The effect on smoking prevalence of whole-of-population reductions and high-risk group reductions was then modelled. Results: In Victoria, there were higher rates of antenatal smoking among single [RR = 4.67 (3.46,4.42)], teenage women [RR (95%CI) = 3.26 (3.00,3.54)] of indigenous ethnicity [RR = 4.39 (3.94, 4.88)] with low income [RR = 4.67 (4.17,5.22)] and low education attainment [RR = 3.89 (3.47,4.36)] who lived in less accessible areas [RR = 2.14 (1.92,2.39)]. However, as each of these high-risk groups represents a relatively small proportion of mothers, most antenatal smokers are aged 25,34, educated, city-based, non-Indigenous and non-impoverished. Conclusions: The majority of Victorian women who smoke in pregnancy do not belong to traditional high-risk groups. Implications: Absolute reductions in smoking prevalence in high-risk groups can potentially be achieved by whole-of-population prevalence reductions, despite a potential continuance in high relative risk among these groups. Conversely, an exclusive focus on smoking reduction in high-risk groups may fail to reduce the whole-of-population antenatal smoking prevalence. [source] Evaluation of immunisation coverage for Aboriginal and Torres Strait Islander children using the Australian Childhood Immunisation RegisterAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 1 2004Brynley P. Hull Objective: To estimate immunisation coverage for routinely administered vaccines among children using receipt of a particular Hib vaccine (PRP-OMP) as a proxy for Indigenous status. Methods: Until May 2000, PRP-OMP was provided only for Indigenous children in all jurisdictions except the Northern Territory. In three one-year ACIR-derived birth cohorts, any child recorded on the ACIR as receiving one or more doses of PRP-OMP as the only Hib vaccine was presumed to be Aboriginal and Torres Strait Islander. Using this proxy, estimated numbers of Indigenous children were compared with Australian Bureau of Statistics estimates, and immunisation status for recommended vaccines was estimated at 12 and 24 months by jurisdiction and remoteness compared with children who received other Hib vaccines (presumed non-Indigenous). Results: The numbers of Aboriginal and Torres Strait Islander children estimated using this ,proxy method' are approximately 42% of those estimated by the ABS. Immunisation coverage (among proxy Indigenous children) at 12 months (72,76%) and 24 months (64,73%) was considerably lower than others (90,94% and 81,88%, respectively). These children had significantly lower coverage when living in accessible areas than remote areas. Conclusions and Implications: These data provide the first national measure of immunisation status and are likely to be a valid measure among those identified. Aboriginal and Torres Strait Islander immunisation coverage is 17% lower with the biggest gaps in urban areas, indicating the need for better quality data informing appropriate interventions. [source] | ||||||||||