In this paper, we explore whether higher corporate tax rates, because they lower the after-tax returns to productivity-enhancing investments, reduce the speed with which small firms converge to the ...productivity frontier. Using data for 11 European countries, we find evidence that their productivity catch-up is slower when the statutory corporate tax rates are higher. In contrast, we find that large firms are instead affected by effective marginal rates. Using the reduced-form model of productivity convergence of Griffith et al. (2009, Journal of Regional Science 49, 689-720), our results are robust to a host of robustness checks and a natural experiment that exploits the 2001 German tax reforms.
Plant phenology is strongly controlled by climate and has consequently become one of the most reliable bioindicators of ongoing climate change. We used a dataset of more than 200 000 records for six ...phenological events of 29 perennial plant species monitored from 1943 to 2003 for a comprehensive assessment of plant phenological responses to climate change in the Mediterranean region. Temperature, precipitation and North Atlantic Oscillation (NAO) were studied together during a complete annual cycle before phenological events to determine their relative importance and potential seasonal carry-over effects. Warm and dry springs under a positive phase of NAO advance flowering, leaf unfolding and fruiting dates and lengthen the growing season. Spatial variability of dates (range among sites) was also reduced during warm and dry years, especially for spring events. Climate during previous weeks to phenophases occurrence had the greatest impact on plants, although all events were also affected by climate conditions several months before. Immediate along with delayed climate effects suggest dual triggers in plant phenology. Climatic models accounted for more than 80% of variability in flowering and leaf unfolding dates, and in length of the growing season, but for lower proportions in fruiting and leaf falling. Most part of year-to-year changes in dates was accounted for temperature, while precipitation and NAO accounted for <10% of dates' variability. In the case of flowering, insect-pollinated species were better modelled by climate than wind-pollinated species. Differences in temporal responses of plant phenology to recent climate change are due to differences in the sensitivity to climate among events and species. Spring events are changing more than autumn events as they are more sensitive to climate and are also undergoing the greatest alterations of climate relative to other seasons. In conclusion, climate change has shifted plant phenology in the Mediterranean region.
Summary
Colletotrichum graminicola causes maize anthracnose, an agronomically important disease with a worldwide distribution. We have identified a fungalysin metalloprotease (Cgfl) with a role in ...virulence. Transcriptional profiling experiments and live cell imaging show that Cgfl is specifically expressed during the biotrophic stage of infection. To determine whether Cgfl has a role in virulence, we obtained null mutants lacking Cgfl and performed pathogenicity and live microscopy assays. The appressorium morphology of the null mutants is normal, but they exhibit delayed development during the infection process on maize leaves and roots, showing that Cgfl has a role in virulence. In vitro chitinase activity assays of leaves infected with wild‐type and null mutant strains show that, in the absence of Cgfl, maize leaves exhibit increased chitinase activity. Phylogenetic analyses show that Cgfl is highly conserved in fungi. Similarity searches, phylogenetic analysis and transcriptional profiling show that C. graminicola encodes two LysM domain‐containing homologues of Ecp6, suggesting that this fungus employs both Cgfl‐mediated and LysM protein‐mediated strategies to control chitin signalling.
Plants are altering their life cycles in response to current climatic change around the globe. More than 200 000 records for six phenological events (leaf unfolding, flowering, fruit ripening, fruit ...harvesting, leaf falling and growing season) of 29 perennial species for the period 1943-2003 recorded throughout Spain provide the longest temporal and the broadest spatial assessment of plant phenology changes in the Mediterranean region. The overwhelming majority of the 118 studied phenophases shifted their dates in recent decades. Such changes differed among phenological events. Leaf unfolding, flowering and fruiting are markedly advancing (-0.48, -0.59 and -0.32 days yr⁻¹, respectively), but only since the mid-1970s. Anemophilous have advanced more days their flowering than entomophilous. However, some species have delayed and others have advanced their leaf falling dates and as a result only a weak shift was observed in this event for the whole of the studied species (+0.12 days yr⁻¹). The growing season lengthened by 18 days, which implies an increase of 8% in the life of annual leaves. Such an increase was achieved mainly through the advance of leaf unfolding dates in the spring, one of the most productive times of year for vegetation in the Mediterranean. Shifts in the plant calendar were accompanied as well by long-term changes in the range of onset dates in 39% of studied phenophases. Leaf unfolding, flowering and growing season tended to reduce spatial variability, reflecting a faster and more synchronized onset (or duration) of phenophases across the study area. Changes in spatial variability may aggravate calendar mismatching with other trophic levels resulting from changes in dates. Because temporal responses differed markedly among species, calendar guilds of plants have changed, which suggests alterations of interspecific relationships in plant communities from Mediterranean ecosystems.
The use of dietary supplements is increasing among athletes, year after year. Related to the high rates of use, unintentional doping occurs. Unintentional doping refers to positive anti-doping tests ...due to the use of any supplement containing unlisted substances banned by anti-doping regulations and organizations, such as the World Anti-Doping Agency (WADA). The objective of this review is to summarize the presence of unlabeled doping substances in dietary supplements that are used in sports.
A review of substances/metabolites/markers banned by WADA in ergonutritional supplements was completed using PubMed. The inclusion criteria were studies published up until September 2017, which analyzed the content of substances, metabolites and markers banned by WADA.
446 studies were identified, 23 of which fulfilled all the inclusion criteria. In most of the studies, the purpose was to identify doping substances in dietary supplements.
Substances prohibited by WADA were found in most of the supplements analyzed in this review. Some of them were prohormones and/or stimulants. With rates of contamination between 12 and 58%, non-intentional doping is a point to take into account before establishing a supplementation program. Athletes and coaches must be aware of the problems related to the use of any contaminated supplement and should pay special attention before choosing a supplement, informing themselves fully and confirming the guarantees offered by the supplement.
Hemibiotrophic plant pathogens first establish a biotrophic interaction with the host plant and later switch to a destructive necrotrophic lifestyle. Studies of biotrophic pathogens have shown that ...they actively suppress plant defenses after an initial microbe-associated molecular pattern-triggered activation. In contrast, studies of the hemibiotrophs suggest that they do not suppress plant defenses during the biotrophic phase, indicating that while there are similarities between the biotrophic phase of hemibiotrophs and biotrophic pathogens, the two lifestyles are not analogous. We performed transcriptomic, histological, and biochemical studies of the early events during the infection of maize (Zea mays) with Colletotrichum graminicola, a model pathosystem for the study of hemibiotrophy. Time-course experiments revealed that mRNAs of several defense-related genes, reactive oxygen species, and antimicrobial compounds all begin to accumulate early in the infection process and continue to accumulate during the biotrophic stage. We also discovered the production of maize-derived vesicular bodies containing hydrogen peroxide targeting the fungal hyphae. We describe the fungal respiratory burst during host infection, paralleled by superoxide ion production in specific fungal cells during the transition from biotrophy to a necrotrophic lifestyle. We also identified several novel putative fungal effectors and studied their expression during anthracnose development in maize. Our results demonstrate a strong induction of defense mechanisms occurring in maize cells during C. graminicola infection, even during the biotrophic development of the pathogen. We hypothesize that the switch to necrotrophic growth enables the fungus to evade the effects of the plant immune system and allows for full fungal pathogenicity.
Carcharodontosaurs were the largest predatory dinosaurs, and their early evolutionary history seems to be more intricate than was previously thought. Until recently, carcharodontosaurs were ...restricted to a group of large theropods inhabiting the Late Cretaceous Gondwanan land masses, but in the last few years Laurasian evidence has been causing a reevaluation of their initial diversification. Here we describe an almost complete and exquisitely preserved skeleton of a medium-sized (roughly six metres long) theropod from the Lower Cretaceous series (Barremian stage) Konservat-Lagerstätte of Las Hoyas in Cuenca, Spain. Cladistic analysis supports the idea that the new taxon Concavenator corcovatus is a primitive member of Carcharodontosauria, exhibiting two unusual features: elongation of the neurapophyses of two presacral vertebrae forming a pointed, hump-like structure and a series of small bumps on the ulna. We think that these bumps are homologous to quill knobs present on some modern birds; the knobs are related to the insertion area of follicular ligaments that anchor the roots of the flight feathers (remiges) to the arm. We propose that Concavenator has integumentary follicular structures inserted on the ulna, as in modern birds. Because scales do not have follicles, we consider the structures anchored to the Concavenator arms to be non-scale skin appendages homologous to the feathers of modern birds. If this is true, then the phylogenetic bracket for the presence of non-scale skin structures homologous to feathers in theropod dinosaurs would be extended to the Neotetanurae, enlarging the scope for explaining the origin of feathers in theropods.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
During the Holocene (last ~11,700 years), societies have continuously modified the landscape of the Mediterranean Basin through changes in land-use, exerting extraordinary pressures onto the ...environment and adding variability to the climate. Despite its importance to current land management, knowledge of how past land-use practices have impacted the regional climate of the Basin remains largely in the scientific sphere. Thereby, this work aims to inform non-scientific actors and practitioners about the environmental effects of past land-use changes on the hydrologic cycle of the Mediterranean Basin. For this purpose we: i) summarize fundamental observed interactions between land-use change and the environment, identified through a semi-systematic review of 23 scientific case-studies from around the Basin; ii) reflect on the consequences to the Mediterranean environment (atmosphere, biosphere, lithosphere, and hydrosphere) in a synthesized and integrated way; iii) argue the need for taking into account the impact of local land-use practices from a regional-scale perspective; iv) highlight the importance of recognizing historical factors, such as past land-use changes, for developing protective strategies in the rural areas of the Basin. With this work, we provide a synthesized and more integrated understanding of the effects of past and local land-use changes in the regional Mediterranean environment, assisting to bridge the gap between scientific findings, Mediterranean watersheds stakeholders, and regional policy-makers.
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•Collects specific case-studies and displays identified effects using a network map•Highlights the importance of historical practices for developing adaptation strategies•Argues the need for regional coordinated action within the Mediterranean Basin•Assists in bridging the gap between scientific findings and policy-makers' knowledge
•Pseuso-Panel for Spanihs Households.•Cigarretes, RYO and Cigars consumption.•Substitution effects between different types of Tobacco.•Tobacco Control policy efficacity.
This paper focuses on the ...substitution effects between different comercial presentations of tobacco in Spain. Concretely, on cigarettes, cigars and RYO. When taxing policies increase tobacco prices these effects might lead changes from more expensive to cheaper products instead of reducing tobacco consumption. We use micro-data for the years 2006 -2012. We estimate a complete model of demand. The own-price, the income and the cross elasticity of each good are estimated. The results show that the own-price elasticity of cigarettes is low and the income elasticity of cigarettes’ demand is very low. Thus in Spain smokers continue to buy cigarettes when the price of cigarettes increases and when cigarette consumers income declines. Moreover the substitutability relationship of cigarettes for cigars and RYO is weak. Thus, cigarettes smokers in Spain are loyal to this product and consider it a normal good. Moreover, cigar consumption presents high own-price and income elasticities, so cigars are luxury goods. Thus unlike cigarettes, cigar sales fall when cigar prices rise or cigar consumers income falls. Finally, RYO and cigarettes are substitutes goods and RYO and cigars are not substitute ones. That means that RYO and cigarettes can satisfy the same need; then to satisfy it the consumers can use almost indistinctibly the one or the other. This is not the case between RYO and cigars.
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