250 research outputs found
Economic growth before the Industrial Revolution: Rural production and guilds in the European Little Divergence
This paper explains how England became a high-income economy from the 15th to 18th centuries. The appropriate level of natural land suitability in the northern region of England before the Industrial Revolution was pivotal in weakening guildsâ power and the diffusion of rural manufacturing. Unlike other European countries, those elements turned into a more efficient allocation of capital between cities and the rural areas and a more efficient shift of labor time from agriculture to manufacturing in the countryside, resulting in a higher income per capita by 1750
The non-degeneracy invariant of Brandhorst and Shimada families of Enriques surfaces
Brandhorst and Shimada described a large class of Enriques surfaces, called
-generic, for which they gave generators for the
automorphism groups and calculated the elliptic fibrations and the smooth
rational curves up to automorphisms. In the present paper, we give lower bounds
for the non-degeneracy invariant of such Enriques surfaces, we show that in
most cases the invariant has generic value , and we present the first known
example of complex Enriques surface with infinite automorphism group and
non-degeneracy invariant not equal to .Comment: 22 pages, 2 figures. Comments welcome
Urban imperviousness effects on summer surface temperatures nearby residential buildings in different urban zones of Parma
Rapid and unplanned urban growth is responsible for the continuous conversion of green or generally natural spaces into artificial surfaces. The high degree of imperviousness modifies the urban microclimate and no studies have quantified its influence on the surface temperature (ST) nearby residential building. This topic represents the aim of this study carried out during summer in different urban zones (densely urbanized or park/rural areas) of Parma (Northern Italy). Daytime and nighttime ASTER images, the local urban cartography and the Italian imperviousness databases were used. A reproducible/replicable framework was implemented named "Building Thermal Functional Area" (BTFA) useful to lead building-proxy thermal analyses by using remote sensing data. For each residential building (n = 8898), the BTFA was assessed and the correspondent ASTER-LST value (ST_BTFA) and the imperviousness density were calculated. Both daytime and nighttime ST_BTFA significantly (p < 0.001) increased when high levels of imperviousness density surrounded the residential buildings. These relationships were mostly consistent during daytime and in densely urbanized areas. ST_BTFA differences between urban and park/rural areas were higher during nighttime (above 1 °C) than daytime (about 0.5 °C). These results could help to identify "urban thermal Hot-Spots" that would benefit most from mitigation actions
A computational view on the non-degeneracy invariant for Enriques surfaces
For an Enriques surface S, the non-degeneracy invariant nd(S) retains information on the elliptic fibrations of S and its polarizations. In the current paper, we introduce a combinatorial version of the non-degeneracy invariant which depends on S together with a configuration of smooth rational curves, and gives a lower bound for nd(S). We provide a SageMath code that computes this combinatorial invariant and we apply it in several examples. First we identify a new family of nodal Enriques surfaces satisfying nd(S)=10 which are not general and with infinite automorphism group. We obtain lower bounds on nd(S) for the Enriques surfaces with eight disjoint smooth rational curves studied by Mendes LopesâPardini. Finally, we recover Dolgachev and KondĆâs computation of the non-degeneracy invariant of the Enriques surfaces with finite automorphism group and provide additional information on the geometry of their elliptic fibrations
Biocides in paints in urban areas: Modelling an underestimated source of environmental contamination
Biocide contamination of receiving waters is generally linked with agriculture. However, recent studies have shown that urban contributions should be also considered. One of the suspected biocide sources in the urban environment is building paint. Biocides like diuron, irgarol, terbutryn, carbendazim, etc., are conventionally used in paint to control fungi, algae, bacteria and other microorganisms that can colonize building façades. The problem of biocides in urban areas is closely linked to meteorological conditions and in particular to rain events. As a consequence, it is important to understand how rainwater collects and transports biocides from façades and how these biocides are transported in sewer systems to receiving waters. In this study, we present a conceptual model describing façade leaching and couple it with a Wind Driven Rain model and a classical hydrological model to compute the contribution of a city to the biocide load from building paint. For the entire city of Lausanne (Switzerland, 200â000 inhabitants), a global production of 2200 kg/year of terbutryn leached by rain was estimated considering local building characteristics and meteorological information. The leaching model fitted well the peak in concentration measured at the bottom of the wall at the initial stage of the rain event. However, concentrations measured in an urban river in the watershed leads to the conclusion that most of this leachate does not reach directly receiving waters, but is infiltrated into soil or reaches the sewers after some delays in drainage pipes. Release of biocides from façade leaching in the environment is systematic during rain event. It is of greater importance to estimate the dynamic of biocides during rain events and to compare these values with dedicated time varying environmental quality criteria
An integrated approach for education/training in Veterinary Public Health (VPH) by the Department of Veterinary Science, University of Turin (DVS_UNITO): the experiences of the “VPH mobile clinic” and the “VPH practical weeks”
Survival and divergence in a small group: The extraordinary genomic history of the endangered Apennine brown bear stragglers
About 100 km east of Rome, in the central Apennine Mountains, a critically endangered population of âŒ50 brown bears live in complete
isolation. Mating outside this population is prevented by several 100 km of bear-free territories. We exploited this natural
experiment to better understand the gene and genomic consequences of surviving at extremely small population size. We found
that brown bear populations in Europe lost connectivity since Neolithic times, when farming communities expanded and forest burning
was used for land clearance. In central Italy, this resulted in a 40-fold population decline. The overall genomic impact of this decline
included the complete loss of variation in the mitochondrial genome and along long stretches of the nuclear genome. Several private and
deleterious amino acid changes were fixed by random drift; predicted effects include energy deficit, muscle weakness, anomalies
in cranial and skeletal development, and reduced aggressiveness. Despite this extreme loss of diversity, Apennine bear genomes show
nonrandom peaks of high variation, possibly maintained by balancing selection, at genomic regions significantly enriched for genes
associated with immune and olfactory systems. Challenging the paradigm of increased extinction risk in small populations, we suggest
that random fixation of deleterious alleles (i) can be an important driver of divergence in isolation, (ii) can be tolerated when balancing
selection prevents random loss of variation at important genes, and (iii) is followed by or results directly in favorable behavioral changes
Enteric alpha-synuclein accumulation impairs intestinal epithelial barrier through inflammasome activation before the onset of brain pathology in a transgenic mouse model of Parkinson's disease
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