Search results for " Cycles"
showing 10 items of 116 documents
Time cycles of homicide in the early modern Nordic area
2020
An extensive body of criminological research has shown that criminaland violent behaviour manifests time patterns in terms of daily,weekly and annual cycles. This is consistent with criminologicalroutine activities theory. Can we generalize these patterns to historicalperiods? In this article, we draw on a recently created uniquedataset, covering the years 1608–1699 in three Nordic regions, toexplore time cycles of offending in the early modern period.Examining daily, weekly and annual cycles, we find that lethalviolence manifested strong time patterns in the early modernperiod. The role of public holidays was central especially in theperiod lasting from Christmas to Midsummer. Probing the …
COLLARD GREEN (BRASSICA OLERACEA VAR. ACEPHALA) CULTIVATION IN SICILY
2013
Collard greens (Brassica oleracea var. acephala) are a group of plants cultivated for its thick, slightly bitter, edible leaves. As other Brassicaceae, have a good nutritional value as they are a good sources of vitamin C and soluble fiber, and contain various compounds with potent anticancer properties. In order to enhance collard cultivation in Sicily, different planting dates were tested. The research was carried out during 2009-2010 in the experimental field of SAgA Department – University of Palermo. Plants of a Sicilian local cultivar, with high vigor, good emission of side shoots, large and moderately curly leaves and long and strong petiole, were planted in three different periods: …
Assessment of water budgets from NWP model analyses and reanalyses over West Africa
2010
International audience; Water budgets from ECMWF reanalysis ERA-Interim and NCEP reanalysis I and II are inter-compared and compared to GPS precipitable water and to a 6-yr so-called "hybrid" budget dataset composed of ALMIP (AMMA Land surface Model Intercomparison Project) offline simulations forced with TRMM precipitation data. Deficiencies are evidenced in the reanalyses which are the most pronounced over the Sahel. Results from operational models (ECMWF-IFS, NCEP-GFS, and ARPEGE-Tropiques) and the special ECMWF AMMA reanalysis confirm and help understand these findings. A bias (~1-2 mm day-1) in precipitation and evapotranspiration leads to an unrealistic view of West Africa as a moistu…
The evolution of transmission mode
2017
This article reviews research on the evolutionary mechanisms leading to different transmission modes. Such modes are often under genetic control of the host or the pathogen, and often in conflict with each other via trade-offs. Transmission modes may vary among pathogen strains and among host populations. Evolutionary changes in transmission mode have been inferred through experimental and phylogenetic studies, including changes in transmission associated with host shifts and with evolution of the unusually complex life cycles of many parasites. Understanding the forces that determine the evolution of particular transmission modes presents a fascinating medley of problems for which there is…
Deficiencies in reporting results of lesbians and gays after donor intrauterine insemination and assisted reproductive technology treatments: a revie…
2015
At a time when increasing numbers of lesbians and gays consider parenthood using reproductive assistance in infertility centers, the present review aims to summarize the results obtained so far by lesbians after intrauterine insemination (IUI) and in-vitro fertilization (IVF) using donor spermatozoa (D-IUI and D-IVF, respectively) and gays entering into gestational-surrogacy programs. Data show that gays display normal semen parameters and lesbians exhibit no specific causes of female infertility except perhaps for polycystic ovary syndrome (PCOS) and some PCOS-related factors. Pair-bonded lesbians entering into D-IUI programs, tend to have higher pregnancy and delivery percentages followin…
Global factors, uncertainty, weather conditions and energy prices: On the drivers of the duration of commodity price cycle phases
2020
We investigate the role of global factors in explaining the length of commodity price cycle phases, using a continuous-time Weibull duration model and data for a panel of 33 countries over the period 1980Q1-2015Q4. We find evidence of increasing (constant) positive duration dependence for commodity price booms and busts (normal time spells). Global macroeconomic conditions - in particular, inflation, economic policy uncertainty and monetary policy actions - significantly affect the duration of all commodity price cycle phases. Global environmental conditions also impact the duration of commodity price booms, with a rise in average temperature (rainfall) increasing (reducing) their length. A…
Inflation dynamics in a model with firm entry and (some) heterogeneity
2014
We analyse the incidence of endogenous entry and firm TFP-heterogeneity on the response of aggregate inflation to exogenous shocks. We build up an otherwise standard DSGE model in which the number of firms is endogenously determined and firms differ in their steady state level of productivity. This splits the industry structure into firms of different sizes. Calibrating the different transition rates, across firm sizes and out of the market we reproduce the main features of the distribution of firms in Spain. We then compare the inflation response to technology, interest rate and entry cost shocks, among others. We find that structures in which large (more productive) firms predominate tend…
A Long Term View on the Short Term Co-movement of Output and Prices in a Small Open Economy
2012
- One assumption behind inflation targeting as objective for monetary policy is that inflation rates in the short run to some extent reflect output cycles. The present paper investigates the historical co-movements of output and prices for a small open raw material based economy, in this case Norway 1830 – 2006. Looking at contemporaneous movements we find more often negative correlations between the two variables than positive. The correlations do not give any evidence of causality. However, they may indicate that supply side shocks, often caused by the foreign sector, were more important for historical output cycles in Norway than assumed hitherto
Non-oxidative dehydroaromatization of methane:an effective reaction regeneration cyclic operation for catalyst life extension
2015
[EN] Non-oxidative methane aromatization is an attractive direct route for producing higher hydrocarbons. It is highly selective to benzene despite the low conversion due to thermodynamic limitations, and Mo/H-ZSM-5, the first catalyst proposed for this reaction, is still considered as one of the most adequate. The major problem of this process is the severe catalyst deactivation due to the rapid build-up of carbonaceous deposits on the catalysts. Here we present an effective regeneration procedure that extends the life of Mo/zeolite based catalysts by combining reaction periods of 1.5 h with 0.5 h regeneration steps in a continuous cyclic mode and methane activation after each regeneration…
The International Business Cycle in a Changing World: Volatility and the Propagation of Shocks
2003
This paper examines the changing relationships between the G-7 countries through VAR models for the quarterly growth rates, estimated both over sub-periods and using a rolling data window. Six trivariate models are estimated, all of which include the US and a European (E15) aggregate. In relative terms, the conditional volatility of E15 growth has declined more since 1980 than the well-documented decline for the US. The propagation of shocks has also changed, with the volatility and propagation effects separated by applying shocks of pre-1980 magnitude to VARs estimated over various periods. Rolling estimation reveals that E15 has a steadily increasing impact on the US economy over time, wh…