234 research outputs found
Macroeconomics of natural disasters
We use the case of the
impact of natural disasters to analyse
strengths and weaknesses of meta-analysis in an emerging research field.
Macroeconomists have published on this issue since 2002 (we identified 22
studies to date). The results of the studies are contradictory and therefore the
need to synthesize the available research is evident. Meta-analysis is a useful
method in this field. First, we observe many methodological differences in
terms of heterogeneity in the data sources, the samples (country coverage and
research period), the econometric specifications and the estimation procedures.
We use meta-analysis both to identify the extent of heterogeneity and its
potential impact and to find out research needs. Second, in this emerging
scientific field the findings are preliminary and often contradictory due to the
scientific process of finding out the ‘true’ effect. Meta-analysis can be used to
distil this effect that often cannot be observed on the basis of individual
studies. Third, as meta-analysis provides a transparent and objective way to
synthesize research, this tool is useful in an area that like natural disasters
impact is vulnerable to bias due to the ideological or intrinsic motivation of the
researcher.
An
aim of our paper is to show how one can use the identified
methodological characteristics to better understand the significance of future
findings. Understanding the robustness and importance of new findings is
crucial because they influence policy decisions with a potentially long-run
impact, especially since both prevention and mitigation require investments
over considerable periods of time. The second aim is to find out what are the
most important research needs from the perspective of the emerging literature.
We identify strengths and weaknesses in terms of coverage and robustness of
control variables showing gaps in the literature and highlighting the importance
of some rigour in the phase of reporting results and, for example, suggest that
it is necessary to include population and institutions more often among the
control variables.
We also provide a
study on the IPCC’s special report Managing the
Risks of Extreme Events and Disasters to Advance Climate Change Adaptation in order
to contrast the meta-analysis and its findings with an influential traditional
review of literature (that also comprises qualitative research).
The two
methods
force two different perspectives on researchers and each
perspective helps to uncover other (aspects of) literatures. Our conclusion is
that research synthesis would benefit from combining the two approaches. A
meta-analysis without a traditional review of the literature is incomplete
Natural disasters impact, factors of resilience and development: A meta-analysis of the macroeconomic literature
We systematize recent macroeconomic empirical literature on the direct and indirect impact of natural disasters providing a meta-analysis of 20 studies published during 2002-2013. We show that the disagreement between these studies is caused by the empirical design, the estimation technique and the resilience factors included in the analyses. The meta-regression suggests that studies that analyse indirect costs have a 88% higher probability to find a positive significant disaster impact than studies of direct costs. If the impact of the disaster is modelled through a disaster indicator, the likelihood of finding a negative and significant disaster impact increases by 64%
Decadal variability 2010-2021 of zooplankton community at the Guadalquivir estuary (southern Spain)
A Long Term Ecological Research Program has been monitoring the Guadalquivir estuary meso- and macro- zooplankton community monthly since January 2010. As an important nursery area for many marine species (fish and crustacean) from the Gulf of Cadiz, whose juveniles and recruits depend on zooplankton as main prey, understanding how abiotic and biotic factors determine zooplankton community structure it´s necessary to unreveal recruitment variability. We sampled throughout the whole salinity gradient, 2 locations, the two diurnal ebb and flood tides during the new moon days using a 100 μm zooplankton net. Zooplankton community is mainly composed by copepods and mysids. While the exotic Acartia tonsa calanoid copepod is the most abundant specie by abundance, mysid Mesopodopsis slabberi contribute the most to total biomass, followed by mysids Rhopalophthalmus tartessicus and Neomysis integer. Other abundant groups were copepods Acartia bifilosa and Acartia clausii, Calanipeda aquaedulcis, Paracalanus parvus and Acanthocyclops robustus, cladocera Pleopis polyphaemoides, together with veliger larvae, Cirripeda and Ostracoda, and Decapoda larvae. About total biodiversity, we found up to 183 species, estimating a total mean Species Richness of 9.7 (minimum 2- maximum 33) per sample, mean Shannon Diversity Index 3.27, Pielou Evenness 0.50 and mean betadiversity 0.630. While copepods area abundant form fall to early spring and summer, mysid density peaks form spring to fall. Community is structured by Salinity, but Temperature, Turbidity, Nitrate, Nitrite and Dissolved Oxygen were also important variables leading spatio-temporal variability, mainly when estuary recives high freshwater discharges from Alcala del Río dam
Myosin-V Opposes Microtubule-Based Cargo Transport and Drives Directional Motility on Cortical Actin
SummaryIntracellular transport is driven by motor proteins that either use microtubules or actin filaments as their tracks [1], but the interplay between these transport pathways is poorly understood [2–4]. Whereas many microtubule-based motors are known to drive long-range transport, several actin-based motors have been proposed to function predominantly in cargo tethering [4–6]. How these opposing activities are integrated on cargoes that contain both types of motors is unknown. Here we use inducible intracellular transport assays to show that acute recruitment of myosin-V to kinesin-propelled cargo reduces their motility near the cell periphery and enhances their localization at the actin-rich cell cortex. Myosin-V arrests rapid microtubule-based transport without the need for regulated auto- or other inhibition of kinesin motors. In addition, myosin-V, despite being an ineffective long-range transporter, can drive slow, medium-range (1–5 μm), point-to-point transport in cortical cell regions. Altogether, these data support a model in which myosin-V establishes local cortical delivery of kinesin-bound cargos through a combination of tethering and active transport
Population dynamic and trophic position of mysid community demonstrates its key role for nursery function in a temperate estuary
Guadalquivir Estuary is a main nursery ground of marine goal species for Gulf of Cadiz fisheries. It is a well-mixed temperate estuary with horizontal salinity gradient and clear seasonal water temperature trend. Mysid community with Mesopodopsis slabberi, Neomysis integer and Rhopalophthalmus tartessicus make up to over 80% of total macrofauna biomass in the estuary. Life history, population structure, secondary production, trophic level and community spatio-temporal dynamic were unravelled combining analysis of long term 16y monitoring data with 2y of in depth population analysis and trophic biomarker studies. Results show a key trophic role in food web, a seasonal trend showing density peaks ( 23, 3 and 6 mg/m3, respectively) in spring-summer and winter marine coastward migration. Despite being euryhaline, the three species of showed unevenly spatial distribution, being salinity the variable best explaining structure changes of mysid assemblage. Inter- and intra-specific euryhalinity differences both for prey and predators seem to determine the entire spatial estuarine community distribution. High secondary production (P/B rates 38.2, 10.3 and 10.7) and food web studies confirm key role of mysids transferring energy up to juveniles (fish and crustaceans) arriving yearly in spring to their nursery area
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