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Translocality is a new phenomenon, recognized in reference to the migration of populations, city-planning and globalization. In our article, we attempt to introduce a new meaning of this term, referring it to the real estate market. Within the work, we research the phenomenon of real estate market subject translocality for all regions of Poland, design a coefficient for measuring translocality and, noting a similarity of the two phenomenon over time, indicate the practical significance of translocality in relation to the speculative price bubble.
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Legislation controlling vehicle emissions has been credited with a general downward trend in NOx (NO2+NO) concentrations in Europe since the 1990's. However, recent studies suggest that traffic (roadside) (TR) NO2 concentrations have not decreased as expected, and in some cases increased, most likely due to the use of oxidation catalysts and particle filters in diesel vehicles (EURO III, IV, V, VI). In this study we describe the time trends in NOx, NO2 and NO concentrations in 9 European cities comparing TR and urban background (UB) monitoring locations. In each city, we collected hourly city-specific NOx, NO, and NO2 data from one TR and one UB monitoring site for each year. We describe hourly, weekly, seasonal and inter-annual patterns for periods corresponding to the implementation dates of various EURO vehicle emission standards regulating NOx emissions. The diurnal patterns in all 9 cities strongly reflected morning and evening traffic. In addition, lower weekend concentrations were observed. The NOx concentrations from the TR sites remain unchanged in the majority of the cities over the study period. When stratified by 3 time periods according to the implementation of the EURO standards, an increasing NO2/NOx ratio in 7/9 cities with time was noted. However, over the same time period the NO/NO2 ratio decreased in 8/9 cities. A permanent inversion of the NO/NO2 ratio was observed to occur in 2003 in 5/9 cities. Our analyses of temporal and diurnal patterns of NOx in European cities show reductions in concentrations consistent with reductions in primary emissions likely arising from the implementation of successive EURO standards. The generally constant or increasing NO2 concentrations in the majority of the cities assessed over the study period underline the need of further regulative measures to meet the air quality standards and consequently to minimise adverse effects on human health. The ongoing collection and analysis of pollution concentrations across the EU is recommended to monitor trends in pollutants associated with adverse health effects.
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In the convergence analysis of numerical methods for solving partial differential equations (such as finite element methods) one arrives at certain generalized eigenvalue problems, whose maximal eigenvalues need to be estimated as accurately as possible. We apply symbolic computation methods to the situation of square elements and are able to improve the previously known upper bound, given in “p- and hp-finite element methods” (Schwab, 1998), by a factor of 8. More precisely, we try to evaluate the corresponding determinant using the holonomic ansatz, which is a powerful tool for dealing with determinants, proposed by Zeilberger in 2007. However, it turns out that this method does not succeed on the problem at hand. As a solution we present a variation of the original holonomic ansatz that is applicable to a larger class of determinants, including the one we are dealing with here. We obtain an explicit closed form for the determinant, whose special form enables us to derive new and tight upper resp. lower bounds on the maximal eigenvalue, as well as its asymptotic behaviour.
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Ice-wedge polygon (IWP) peatlands in the Arctic and Subarctic are extremely vulnerable to climatic and environmental change. We present the results of a multidisciplinary paleoenvironmental study on IWPs in the northern Yukon, Canada. High-resolution laboratory analyses were carried out on a permafrost core and the overlying seasonally thawed (active) layer, from an IWP located in a drained lake basin on Herschel Island. In relation to 14 Accelerator Mass Spectrometry (AMS) radiocarbon dates spanning the last 5000 years, we report sedimentary data including grain size distribution and biogeochemical parameters (organic carbon, nitrogen, C/N ratio, δ13C), stable water isotopes (δ18O, δD), as well as fossil pollen, plant macrofossil and diatom assemblages. Three sediment units (SUs) correspond to the main stages of deposition (1) in a thermokarst lake (SU1: 4950 to 3950 cal yrs BP), (2) during transition from lacustrine to palustrine conditions after lake drainage (SU2: 3950 to 3120 cal yrs BP), and (3) in palustrine conditions of the IWP field that developed after drainage (SU3: 3120 cal yrs BP to 2012 CE). The lacustrine phase (pre 3950 cal yrs BP) is characterized by planktonic-benthic and pioneer diatom species indicating circumneutral waters, and very few plant macrofossils. The pollen record has captured a regional signal of relatively stable vegetation composition and climate for the lacustrine stage of the record until 3950 cal yrs BP. Palustrine conditions with benthic and acidophilic diatom species characterize the peaty shallow-water environments of the low-centered IWP. The transition from lacustrine to palustrine conditions was accompanied by acidification and rapid revegetation of the lake bottom within about 100 years. Since the palustrine phase we consider the pollen record as a local vegetation proxy dominated by the plant communities growing in the IWP. Ice-wedge cracking in water-saturated sediments started immediately after lake drainage at about 3950 cal yrs BP and led to the formation of an IWP mire. Permafrost aggradation through downward closed-system freezing of the lake talik is indicated by the stable water isotope record. The originally submerged IWP center underwent gradual drying during the past 2000 years. This study highlights the sensitivity of permafrost landscapes to climate and environmental change throughout the Holocene.
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Organic-rich black shale of the Upper Yangtze Basin from the Late Ordovician and Early Silurian is considered an excellent source rock in South China. The formation and preservation conditions of this resource are revealed by its geochemical characteristics in this study. Geochemical indices, including redox indices (V/(V + Ni), V/Cr, V/Sc, and Ni/Co) and primary productivity indices (P/Ti and Ba/Al), and paleoclimate, clastic flux and sedimentary rate analyses are presented to investigate the accumulation mechanism of organic matter. Redox indices suggest that a stagnant, anoxic environment predominated in the Upper Yangtze Basin during accumulation of Wufeng and Longmaxi formations. In contrast, ventilated and oxygenated marine conditions pervaded the Upper Yangtze Basin during deposition of Linxiang and Guanyinqiao formations. The concentrations of V and U demonstrate that accumulation of organic matter was mainly controlled by redox conditions. Besides, such factors as clastic fluxes, fresh water inflows or a mixed deposition with a rapid sedimentary rate cannot be ignored due to their influences on organic matter enrichment and preservation. However, weak co-variance relationship of TOC content and productivity proxies, including P/Ti and Ba/Al, demonstrates that the accumulation of organic matter was not controlled by primary productivity. Results of the present study suggest a depositional model that stresses the importance of tectonic movements and glacial events on the accumulation and preservation of organic matter. The model shows that the Upper Yangtze Basin was a semi-restricted basin system influenced by the isolation of Xuefeng, but also it implies that oxygen-depleted bottom water of the basin favored the accumulation and preservation of sedimentary organic matter, resulting in the formation of organic-rich black shale.
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The use of biophysical models to support increased food production and environmental protection is on the rise. This paper reviews the demand for, and trends in, soil property data for various biophysical models being used in Victoria, Australia, over the 2009–2014 period. The study used surveys, workshops and interviews with public sector modellers to examine perceptions of the soil parameters that affect model sensitivity and error. Although the data requirements of models have remained similar over the 5-year period, the diversity of models used has decreased. There is evidence of increased application of models at point/site scale to support grains, dairy and livestock production industries in Victoria. Opportunities are identified to deliver finer scale soil data from digital soil mapping to better meet modelling requirements for agricultural industries in Victorian landscapes.
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•Chennai (India) received the highest rainfall of 490 mm on 1 Dec 2015.•This study looked at NOAA/NESDIS global analysis of SST anomaly (°C).•Revival of 769 km long Buckingham Canal essential for flood mitigation.•Renovating canals, ponds, and lakes crucial for flood prevention.•India needs better strategies to adapt to future extreme weather situations.
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The French soil-test database (Base de Données d'Analyses de Terre: BDAT) is populated with analytical results of agricultural topsoil samples requested by farmers for fertilization planning. The coordinates of the farms are unknown due to data confidentiality policies, and the best available georeference is at level of municipality. We compared four approaches for mapping soil texture of agricultural land in Region Centre (France) using BDAT data: 1) a reference approach of mapping the mean of the aggregated data by municipality, 2) a boosted regression tree (BRT) model fitted with the municipality-averaged data, 3) area-to-point cokriging (AToP CK), and 4) a regression kriging version of this (AToP RCK, for which the BRT predictions were used to give the trend). Specifically, parameters for these last two approaches were fitted through the summary statistics approach to AToP kriging, which accounts for the full set of municipality summary statistics data (i.e. the mean, variance and number of measurements from each municipality). We could thus determine whether more complex and statistically-challenging approaches improve our knowledge on the spatial distribution of soil texture compared with maps of data aggregated by municipality. Texture data from 105 sites form the French soil monitoring network (Réseau de Mesures de la Qualité des Sols: RMQS) were used for independent validation. In general, the R2 was greater for sand (average R2=0.69) and silt (average R2=0.72) than for clay (average R2=0.40). The three methods for disaggregating the summary statistics data (BRT, AToP CK, and AToP RCK) showed similar prediction accuracies—although BRT predictions showed the greatest bias—and were better than the BDAT reference approach. AToP RCK was able to give similar prediction accuracy to BRT modelling alone, reduced the bias considerably, and gave a reasonable (although slightly conservative) assessment of prediction uncertainty. The results indicate that geostatistical methods for change of support expand the utility of aggregated data from soil-test databases.
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Kveithola is a glacially-carved, E-W trending trough located in the NW Barents Sea, an epicontinental shelf sea of the Arctic Ocean located off northern Norway and Russia. A set of confined sediment drifts (the “Kveithola Drift”) is located in the inner part of the trough. In general, drift deposits are commonly characterized by high lateral continuity, restricted occurrence of hiatuses and relatively high accumulation rates, and thus represent excellent repositories of paleo-environmental information. We provide for the first time a detailed morphological and seismostratigraphic insight into this sediment drift, which is further supported by some preliminary lithological and sedimentological analyses. The complex morphology of the drift, imaged by combining all available multibeam data, includes a main and a minor drift body, two drift lenses in the outer part of the trough, more or less connected drift patches in the innermost part and small perched sediment patches in a structurally-controlled channel to the north. The seismic (PARASOUND) data show that the main and minor drift bodies are mainly well-stratified, characterized by sub-parallel reflections of moderate to high amplitude and good lateral continuity. The reflectors show an abrupt pinch-out on the northern edge where a distinct moat is present, and a gradual tapering to the south. Internally we identify the base of the drift and four internal horizons, which we correlate throughout the drift. Two units display high amplitude reflectors, marked lensoidal character and restricted lateral extent, suggesting the occurrence of more energetic sedimentary conditions. Facies typical for contourite deposition are found in the sediment cores, with strongly bioturbated sediments and abundant silty/sandy mottles that contain shell fragments. These characteristics, along with the morphological and seismic information, suggest a strong control by a bottom current flowing along the moat on the northern edge of the drift. Though both Atlantic and Arctic waters are known to enter the trough, from the west and the north respectively, brine-enriched shelf water (BSW) produced during winter and flowing westward in the moat, is suggested to be responsible for the genesis of the Kveithola Drift. The formation of BSW is inferred to have started around 13 cal ka BP, the onset of drift deposition, suggesting that conditions leading to atmospheric cooling of the surface waters and/or the presence of coastal polynyas and wind or floating ice shelves have persisted on the western Barents Shelf since that time. The units inferred to have been deposited under more energetic sedimentary conditions (tentatively dated to the Younger Dryas and to 8.9–8.2 cal ka BP) are suggestive of stronger BSW formation. In general, we infer that variations in the bottom current regime were mainly related to BSW formation due to atmospheric changes. They could also have been a response to successive episodes of grounded and sea ice retreat that allowed for a first limited, later open shelf current, which progressively established on the western Barents Sea shelf.
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A model is presented for the supervised learning problem where the observations come from a fixed number of pre-specified groups, and the regression coefficients may vary sparsely between groups. The model spans the continuum between individual models for each group and one model for all groups. The resulting algorithm is designed with a high dimensional framework in mind. The approach is applied to a sentiment analysis dataset to show its efficacy and interpretability. One particularly useful application is for finding sub-populations in a randomized trial for which an intervention (treatment) is beneficial, often called the uplift problem. Some new concepts are introduced that are useful for uplift analysis. The value is demonstrated in an application to a real world credit card promotion dataset. In this example, although sending the promotion has a very small average effect, by targeting a particular subgroup with the promotion one can obtain a 15% increase in the proportion of people who purchase the new credit card.
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