Insect midgut cadherins function as receptors and play critical roles as protein receptors of insecticidal Bacillus thuringiensis (Bt) toxins used as biopesticides and in Bt transgenic crops ...worldwide. Here, we cloned and characterized the full‐length midgut cadherin (CmCad) cDNA from the rice leaffolder (Cnaphalocrocis medinalis), a destructive pest of rice in many Asian countries. Expression of recombinant proteins corresponding to the extracellular domain of CmCad allowed testing binding of Cry proteins. Results from in vitro ligand blotting and enzyme‐linked immunosorbent assays supported that the extracellular domain of CmCad contains regions recognized by both Cry1Ac and Cry2Aa. Molecular modelling and docking simulations indicated that binding to both Cry1Ac and Cry2Aa is localized primarily within a CmCad motif corresponding to residues T1417–D1435. A recombinant CmCad protein produced without residues T1417–D1435 lacked binding to Cry1Ac and Cry2Aa, confirmed our modelling predictions that CmCad has a shared Cry1Ac and Cry2Aa binding site. The potential existence of a shared binding region in CmCad suggests that caution should be taken when using combinations of Cry1Ac and Cry2Aa in pyramided transgenic rice, as their combined use could speed the evolution of resistance to both toxins.
The truncated CR9‐11 peptide from C. medinalis cadherin showed the binding ability to Cry1Ac and Cry2Aa.
Molecular docking identified a conserved cadherin binding motif (T1417–D1435) as predicted to be involved in these binding.
Lack of Cry1Ac and Cry2Aa binding to a mutant CmCad‐CR9‐11 region with a deletion of the motif provided further evidence supporting this motif as the binding site shared by Cry1Ac and Cry2Aa.
Adoption of better technologies is a crucial way for developing countries to close productivity gaps with leading economies. However, the possibility of growing through technological adoption depends ...decisively on the country’s absorptive capacity. We build a theoretical model of technology adoption that focuses on four factors that shape the countries’ technological absorptive capacity, namely: (i) years of education; (ii) quality of the educational system; (iii) barriers that impede the entry and exit of firms; and (iv) the institutions that enhance or impede the diffusion of new technologies. We calibrate the model for a sample of 86 economies. The USA is our benchmark leading economy. We disentangle the relative weight of each development factor in explaining per capita income differences and study patterns in relationships between the type of development barrier and the level of development. Our results show that in relative terms, years of education and education system quality along with high barriers to opening new firms are the main impediments that middle- to high-income economies face in closing the gap with the USA. Education as a whole (quality plus years of education) explains 50% of the gap between high-income countries (HICs) and the USA, while the entry costs account for nearly 25% of this gap. A remarkable result is the small effect that individual reforms have on steady-state productivity in low-income countries (LICs). Outside of institutional framework, the remaining three factors are individually responsible for less than 15% of the gap. This result is explained by poor global absorptive capacity that reduces the effect of each factor when implemented individually. In fact, there are significant nonlinearities between development level and the effects of individual reforms, which are due to the strong complementarities between the different development factors.
Soil organic carbon stock (SOCS) assessments at a national level are essential in the climate change mitigation role. Our study provides the first assessment of the SOC stored in entire Spanish ...surface soils obtained from one sampling protocol within a regular sampling framework in a short edaphic time. In this study, we analysed topsoil samples (0–30cm) from 4401 locations. SOC, soil bulk density and stoniness were measured to estimate SOCS. The results showed that half the Spanish areas obtained a SOC value below 1%. There is inherently wide spatial variability in SOC contents in Spain with low SOC concentration levels located in southern areas. The lowest SOC levels were associated with agricultural soils. However, no statistically significant differences were found between forestlands and grasslands. The mean SOCS in the Spanish topsoil layer was 56.57MgCha−1 and the total stored in topsoil was 2.8 Pg C. We were surprised to find that our estimates were 40% lower than those known to date for Spain. The results herein highlight the potential land use change for SOC sequestration in Spanish soils. Certain changes in agricultural practises (conservation tillage) or converting some unproductive croplands into grasslands or forestlands can increase carbon sequestration in soils.
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•We model spatial variability in Spanish soil organic carbon•We analysed topsoil samples from 4401 locations within a regular sampling.•We use a simple geostatistical method to estimate SOCS.•Half Spanish area obtained a SOC value below 1%.•Our estimates were 40% lower than was known to date for Spain.
Bilinguals have been shown to outperform monolinguals in a variety of tasks that do not tap into linguistic processes. The origin of this bilingual advantage has been questioned in recent years. ...While some authors argue that the reason behind this apparent advantage is bilinguals' enhanced executive functioning, inhibitory skills and/or monitoring abilities, other authors suggest that the locus of these differences between bilinguals and monolinguals may lie in uncontrolled factors or incorrectly matched samples. In the current study we tested a group of 180 bilingual children and a group of 180 carefully matched monolinguals in a child-friendly version of the ANT task. Following recent evidence from similar studies with children, our results showed no bilingual advantage at all, given that the performance of the two groups in the task and the indices associated with the individual attention networks were highly similar and statistically indistinguishable.
► Long-term conservation tillage systems improved the crop response to N fertilization. ► Intensive tillage reduced soil water content and accumulated nitrates in the soil. ► No-tillage improved the ...environmental and economical sustainability of the system.
Conservation tillage systems (no-tillage, NT; and minimum tillage, MT) are being adopted in rainfed agroecosystems of the Mediterranean basin where water availability is the main limiting factor for crop productivity. We hypothesized that long-term adoption of conservation tillage systems would increase water use efficiency (WUE) and its response to N fertilizer additions due to improved soil water content.
A field experiment was established in 1996 on a loamy Xerofluvent Typic in the Ebro river valley (NE Spain). The experiment compared three nitrogen (N) fertilization levels (zero, 0
kg
N
ha
−1, medium, 60
kg
N
ha
−1, and high, 120
kg
N
ha
−1), under three tillage systems (CT, conventional tillage; MT and NT), annually cropped to barley (
Hordeum vulgare, L.) as is usual in the region. Ten years after the experiment establishment, during four consecutive growing seasons, 2005–2006 to 2008–2009, we evaluated the response of soil water content, soil nitrate, above-ground dry matter, grain yield and yield components to long-term (>10
years) tillage and N fertilization treatments.
The long-term sustainability of NT and MT was confirmed. Mean yield and WUE under long-term conservation tillage systems were 66% and 57% higher than under CT, respectively. This improvement was mainly attributed to improved soil water usage under conservation tillage, mainly due to reduced water use during the pre-anthesis period. However, in a wet year yield did not significantly differ among tillage systems. The improvement of WUE with N fertilization was confirmed under NT, which medium and high N fertilizer level increased 98% mean grain yield and 77% mean WUE compared to CT. The increased response of crop and yield to N fertilization under NT was due to improved soil water content. Soil N accumulation together with the lower water accumulation explained the lack of response to N fertilization under CT, even on a wet growing season (i.e., 2008–2009).
Long-term NT adoption was a sustainable practice for barley monoculture in the region, allowing for reduced costs and yield increase with N fertilizer additions. N fertilizer rates on rainfed Mediterranean croplands should be adjusted depending on the reduction of tillage intensity and rainfall of the year. In our system and as an example for this agroecosystems, N fertilizer rates should be kept at or below 60
kg
N
ha
−1, and should be further reduced on intensively cultivated soils.
The response of soil CO2 flux to long-term tillage practices (no-tillage, NT; minimum tillage, MT; conventional tillage, CT) and N fertilization level (zero; medium, 60 kg N ha-1; high, 120 kg N ...ha-1) was studied during three growing season in a rainfed Mediterranean agroecosystem. Soil CO2 flux was related to the crop growth, with the highest flux during spring (i.e., March-May). Tillage and N fertilization effects on soil CO2 flux during growing seasons depended on weather conditions: greater soil CO2 flux under MT and NT on dry years, greater under CT and MT on a wet year. Nitrogen fertilization affected soil CO2 flux during this wet growing season: flux with N fertilizer additions was higher than flux on the unfertilized plots. Thirteen years after establishment of the experiment, the soil organic carbon (SOC) stock under long-term NT was 3.9 Mg C ha-1 greater than under CT and 4.3 Mg C ha-1 greater than under MT. The SOC stocks with N fertilizer additions were 4 Mg C ha-1 greater than the stock on unfertilized plots. The increase of C inputs with N fertilization was more pronounced under NT than under MT or CT. For this reason the increased response of SOC stock to N fertilization is expected under NT in a longer period of time. The product between soil water content and soil temperature explained between 75 and 94% of the seasonal variability of soil CO2 flux. However, soil CO2 flux and SOC stock were hardly related.
We typically observe a decrement in vigilance with time-on-task, which favors the propensity for mind-wandering, i.e., the shifting of attention from the task at hand to task-unrelated thoughts. ...Here, we examined participants’ mind-wandering, either intentional or unintentional, while performing vigilance tasks that tap different components of vigilance. Intentional mind-wandering is expected mainly when the arousal component is involved, whereas unintentional mind-wandering is expected mainly in tasks involving the executive component. The Psychomotor Vigilance Task (PVT) assessed the arousal component, whereas the Sustained Attention to Response task (SART) assessed the executive component of vigilance. The two types of mind-wandering were probed throughout task execution. The results showed that the overall rate of mind-wandering was higher in the PVT than in the SART. Intentional mind-wandering was higher with the PVT than with the SART, whereas unintentional mind-wandering was higher with the SART than with the PVT. Regarding mind-wandering as a function of vigilance decrement with time-on-task, unintentional mind-wandering in the PVT increased between blocks 1 and 2 and then stabilized, whereas a progressive increase was observed in the SART. Regarding intentional mind-wandering, a progressive increase was only observed in the SART. The differential patterns of intentional and unintentional mind-wandering in both tasks suggest that, intentional mind wandering occurs mainly in arousal tasks in which propensity to mind-wander has little impact on task performance. However, unintentional mind-wandering occurs mainly in executive tasks as a result of a failure of cognitive control, which promotes attentional resources to be diverted toward mind-wandering. These results are discussed in the context of the resource-control model of mind-wandering.
•Regional SOC modelling in Spanish Mediterranean coast performed.•Cover cropping and available exogenous organic matter input simulated.•Large potential for cover cropping to accumulate ...SOC.•Composting and anaerobic digestion help mitigate GHG emissions.
Agriculture in the Mediterranean basin is currently contributing to greenhouse gas emissions (GHG) and in the future is expected to be strongly affected by climate change. Increasing soil organic carbon (SOC) via soil organic matter (SOM) improvement is widely regarded as a way to both mitigate and adapt to climate change. Using as a case study the Mediterranean coastal area in Spain, which is regarded as one of the most intensively managed areas in Europe for orchards and horticultural cropping, we analyzed the potential for climate change mitigation of introducing different practices that are expected to increase SOC. We selected both as a single measure and in combination, cover cropping and application to the soil of the available underutilized exogenous organic matter (EOM), treated (e.g. composted or digested) or non-treated. These practices were compared against a baseline scenario that intended to reflect the current practices in the area (e.g. all livestock manure produced in the area is applied to the agricultural soil). We carried out a modelling exercise at the regional scale using the agricultural activity data and current climatic conditions as inputs. Modelling runs were performed coupling a widely used dynamic model of SOC turnover (RothC) with a model to simulate the GHG emissions from EOM processing or storage prior to soil application (SIMSWASTE).
Results indicate that the most promising practice, considered as a single measure and with respect to the baseline, was introducing cover crops in woody cropping systems. This practice resulted in an increase of 0.44MgCha−1 yr−1 during the first 20 years (range 0.41–0.52MgCha−1 yr−1) and led to a total SOC accumulation of about 30TgC after 100 years. Amendment of all agricultural land with available underutilized EOM resulted in an increase of up to 0.09MgCha−1 yr−1 (range 0.07–0.16MgCha−1 yr−1) as a single measure (urban waste) and 0.13MgCha−1 yr−1 (range 0.11–0.21MgCha−1 yr−1) as a combined measure (urban waste and composted agroindustry by-products), leading to a total SOC accumulation of about 7TgC (urban waste) and 10Tg C (urban waste and composted agroindustry by-products) after 100 years. Manure anaerobic digestion or composting as a single measure did not result in significant SOC changes but, if GHG emissions and savings from manure storage and processing management stages are considered, they could help to reduce about 4.3 (anaerobic digestion) or 1.1Tg CO2eq yr−1 (composting) in the study area, which represents a significant amount compared with total agricultural emissions in Spain.
Abstract
Meridional circulation regulates the Sun’s interior dynamics and magnetism. While it is well accepted that meridional flows are poleward at the Sun’s surface, helioseismic observations have ...yet to provide a definitive answer for the depth at which those flows return to the equator, or the number of circulation cells in depth. Here, we explore the observability of multiple circulation cells stacked in radius. Specifically, we examine the seismic signature of several meridional flow profiles by convolving time–distance averaging kernels with mean flows obtained from a suite of 3D hydrodynamic simulations. At mid and high latitudes, we find that weak flow structures in the deep convection zone can be obscured by signals from the much stronger surface flows. This contamination of 1–2 m s
−1
is caused by extended side lobes in the averaging kernels, which produce a spurious equatorward signal with flow speeds that are 1 order of magnitude stronger than the original flow speeds in the simulations. At low latitudes, the flows in the deep layers of the simulations are stronger (>2 m s
−1
) and multiple cells across the convection zone can produce a sufficiently strong signal to survive the convolution process. Now that meridional flows can be measured over two decades of data, the uncertainties arising from convective noise have fallen to a level where they are comparable in magnitude to the systematic biases caused by nonlocal features in the averaging kernels. Hence, these systematic errors are beginning to influence current helioseismic deductions and need broader consideration.
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•Prolonged driving time induces driver fatigue.•Driver’s EEG power spectra and saccadic velocity changed over a 2-h simulated drive.•Power spectra of the delta EEG band showed an ...inverted U-shaped quadratic trend.•Power spectra of the beta band showed an increasing linear trend.•Driver’s reduced levels of arousal might explain EEG power changes.
Driver fatigue can impair performance as much as alcohol does. It is the most important road safety concern, causing thousands of accidents and fatalities every year. Thanks to technological developments, wearable, single-channel EEG devices are now getting considerable attention as fatigue monitors, as they could help drivers to assess their own levels of fatigue and, therefore, prevent the deterioration of performance. However, the few studies that have used single-channel EEG devices to investigate the physiological effects of driver fatigue have had inconsistent results, and the question of whether we can monitor driver fatigue reliably with these EEG devices remains open. Here, we assessed the validity of a single-channel EEG device (TGAM-based chip) to monitor changes in mental state (from alertness to fatigue). Fifteen drivers performed a 2-h simulated driving task while we recorded, simultaneously, their prefrontal brain activity and saccadic velocity. We used saccadic velocity as the reference index of fatigue. We also collected subjective ratings of alertness and fatigue, as well as driving performance. We found that the power spectra of the delta EEG band showed an inverted U-shaped quadratic trend (EEG power spectra increased for the first hour and half, and decreased during the last thirty minutes), while the power spectra of the beta band linearly increased as the driving session progressed. Coherently, saccadic velocity linearly decreased and speeding time increased, suggesting a clear effect of fatigue. Subjective data corroborated these conclusions. Overall, our results suggest that the TGAM-based chip EEG device is able to detect changes in mental state while performing a complex and dynamic everyday task as driving.
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