Grain crops are an important part of the human diet, accounting for a third of the consumed calories. Throughout human history, annual grain crops with high yields have been obtained through ...domestication. However, the “annual” characteristic brings associated a series of economic and environmental disadvantages, such as soil erosion or low soil resources use, that can be solved if the agriculture of annual varieties evolves towards perenniality. For this reason, there are numerous research groups dedicated to study and obtain perennial varieties of the most cultivated grain crops. In this review article, we have summarized the most important advances related to the subject, focusing on the domestication and hybridization of the most productive grains globally: wheat, rice, maize, rye and sorghum. We highlight their benefits for sustainable agriculture worldwide due to perennial grains may contribute to reducing erosion, acting avoiding carbon losses, reducing nutrient losses to waters or capturing nutrients deeper in soil when they are scarce, reducing farm costs and thus, increasing the effectiveness of agricultural grain crops. Despite perennial grain crops having disadvantages, they possess outstanding characteristics which make them resilient crops to deal with the imminent climate change. However, maintaining the perenniality trait without reducing genetic biodiversity is a great challenge of current scientific importance that must be deeply considered.
•Grain crops constitute an important part of the human diet.•Perennial grain crops can reduce environmental problems associated with annual crops.•There are breeding programs to breed perennial varieties of wheat, rice and maize.•The first perennial grain cultivars, such as Kernza, are being introduced in the market.
In this work, we have developed a semi‐analytical solution for organic carbon oxidation coupled to the reduction‐oxidation sequence assuming the Partial Equilibrium Approach (PEA) and using the ...decoupling procedure of De Simoni et al. (2005), https://doi.org/10.1029/2005WR004056. Our solution was applied to two very simple cases. The first assumes only advective transport and the second only diffusive transport. Comparison with a numerical solution showed the adequacy of our analytical solution to be implemented in several scenarios, for example, in organic carbon oxidation in the unsaturated zone or in highly heterogeneous advective domains. We found that for the diffusion case the PEA produced spurious reactions, such as oxidation of N2 by O2 when compared with an approach using full kinetics. These reactions do not occur in the advection case. An analysis with the semi‐analytical solution revealed that they are the result of a combination of diffusive fluxes and the fact that the PEA assumes the electron acceptors to react with each other in equilibrium. Our analytical solutions are capable to quantify this shortcoming, becoming a tool to validate numerical models using PEA to describe organic carbon oxidation.
Key Points
A semi‐analytical solution for organic carbon oxidation has been developed
The partial equilibrium approach combined with diffusion can give spurious oxidation reactions
The fully kinetic and partial equilibrium approach give similar results for advective cases
Summary
Daratumumab is a CD38‐targeting monoclonal antibody approved for intravenous (IV) infusion for multiple myeloma (MM). We describe the Phase II PLEIADES study of a subcutaneous formulation of ...daratumumab (DARA SC) in combination with standard‐of‐care regimens: DARA SC plus bortezomib/lenalidomide/dexamethasone (D‐VRd) for transplant‐eligible newly diagnosed MM (NDMM); DARA SC plus bortezomib/melphalan/prednisone (D‐VMP) for transplant‐ineligible NDMM; and DARA SC plus lenalidomide/dexamethasone (D‐Rd) for relapsed/refractory MM. In total, 199 patients were treated (D‐VRd, n = 67; D‐VMP, n = 67; D‐Rd, n = 65). The primary endpoints were met for all cohorts: the ≥very good partial response (VGPR) rate after four 21‐day induction cycles for D‐VRd was 71·6% 90% confidence interval (CI) 61·2–80·6%, and the overall response rates (ORRs) for D‐VMP and D‐Rd were 88·1% (90% CI 79·5–93·9%) and 90·8% (90% CI 82·6–95·9%). With longer median follow‐up for D‐VMP and D‐Rd (14·3 and 14·7 months respectively), responses deepened (ORR: 89·6%, 93·8%; ≥VGPR: 77·6%, 78·5%), and minimal residual disease–negativity (10‒5) rates were 16·4% and 15·4%. Infusion‐related reactions across all cohorts were infrequent (≤9·0%) and mild. The median DARA SC administration time was 5 min. DARA SC with standard‐of‐care regimens demonstrated comparable clinical activity to DARA IV–containing regimens, with low infusion‐related reaction rates and reduced administration time.
Public service providers increasingly encourage users to actively coproduce as a means to enhance public service provision. But what drives users to coproduce? Using a unique combination of survey ...and actual behavior log‐data of 9992 smart public service users who reported service‐related issues, we examine the extent to which users' self‐centered and community‐centered motivations are associated with their actual reporting behavior as well as the effort intensity of such behavior. Our findings suggest that users' self‐centered motivations are positively related to their actual reporting behavior and effort intensity, while community‐centered motivations do not show a significant association. Our study highlights the importance of self‐centered motivations in (digital) coproduction and co‐assessment. It also showcases the potential of using log data from public services to measure actual coproduction behavior instead of relying solely on self‐reported behavior.
This study examines how the combined effects of work environmental factors and leadership behaviours lead to the presence (or absence) of industrial employees job performance by applying fuzzy-set ...qualitative comparative analysis (fsQCA). A sample composed of supervisor-subordinate dyads was used to test the propositions of this study. The results show that the most important variables are transformational leadership and social support. Employee empowerment and task significance seem to play a secondary role in leading to employee job performance. These findings support the need for managers to use positive leadership to manage human resources. This paper contributes to the advancement of the knowledge of employee job performance through the identification of the combinations of conditions that can lead to the presence or absence of this important organizational outcome. Directions for future studies are commented on at the end of the paper.
Aphids commonly harbour facultative bacterial endosymbionts and may benefit from their presence through increased resistance to parasitoids. This has been demonstrated for Hamiltonella defensa and ...Serratia symbiotica, while a third common endosymbiont, Regiella insecticola, did not provide such protection. However, this symbiont was recently detected in a highly resistant clone of the peach-potato aphid, Myzus persicae, from Australia. To test if resistance was indeed conferred by the endosymbiont, we eliminated it from this clone with antibiotics, and we transferred it to two other clones of the same and one clone of a different aphid species (Aphis fabae). Exposing these lines to the parasitoid Aphidius colemani showed clearly that unlike other strains of this bacterium, this specific isolate of R. insecticola provides strong protection against parasitic wasps, suggesting that the ability to protect their host against natural enemies may evolve readily in multiple species of endosymbiotic bacteria.
Redox potential (Eh) measurements are widely used as indicators of the dominant reduction–oxidation reactions occurring underground. Yet, Eh data are mostly used in qualitative terms, as actual ...values cannot be used to distinguish uniquely the dominant redox processes at a sampling point and should therefore be combined with a detailed geochemical characterization of water samples. In this work, we have intensively characterized the redox potential of the first meter of soil in an infiltration pond recharged with river water using a set of in situ sensors measuring every 12 min during a 1 year period. This large amount of data combined with hydrogeochemical campaigns allowed developing a reactive transport model capable of reproducing the redox potential in space and time together with the site hydrochemistry. Our results showed that redox processes were mainly driven by the amount of sedimentary organic matter in the system as well as by seasonal variation of temperature. As a subsidiary result, our work emphasizes the need to use a fully coupled model of flow, heat transport, solute transport, and the geochemical reaction network to fully reproduce the Eh observations in the topsoil.
Commitments to curb illegal logging and deforestation have proliferated in recent years with the increase of global trade in tropical timber and wood products. While they reflect international ...sustainability demands, the employed mechanisms to assure timber legality verification may not reflect conditions faced by local private sector actors. Facing rapid forest loss and limited foreign market access, government of Myanmar started reforming its forest policy to include a system of timber legality verification. Drawing on policy analysis and mixed-methods field research, we evaluate the feasibility of the policy reform to achieve economic and environmental upgrading in the timber value chain. Our findings question the transformative capacity of this policy reform. Not only that it failed to meet its sustainability goals, it has also created favourable conditions for a race to the bottom and concentration in the timber value chain. Economic and environmental upgrading take place at the expense of private smallholders who are expected to address a range of obstacles, including limited access to inputs, quality downgrading, and increased operational costs, which hamper their performance. To prevent socio-environmental losses, forest-sector regulatory reforms should be particularly mindful of these challenges in the midstream segment of the value chain.
•Feasibility of policy reform to achieve economic and environmental upgrading.•The case of timber and wood products value chain in Myanmar.•Policy analysis and mixed-methods field research.•The reform failed to meet its sustainability goals.•Conditions for race to the bottom and concentration in the timber value chain.
Degradation of emerging organic compounds in saturated porous media is usually postulated as following simple low-order models. This is a strongly oversimplified, and in some cases plainly incorrect ...model, that does not consider the fate of the different metabolites. Furthermore, it does not account for the reversibility in the reaction observed in a few emerging organic compounds, where the parent is recovered from the metabolite. One such compound is the antibiotic sulfamethoxazole (SMX). In this paper, we first compile existing experimental data to formulate a complete model for the degradation of SMX in aquifers subject to varying redox conditions, ranging from aerobic to iron reducing. SMX degrades reversibly or irreversibly to a number of metabolites that are specific of the redox state. Reactions are in all cases biologically mediated. We then propose a mathematical model that reproduces the full fate of dissolved SMX subject to anaerobic conditions and that can be used as a first step in emerging compound degradation modeling efforts. The model presented is tested against the results of the batch experiments of Barbieri et al. (2012) and Nödler et al. (2012) displaying a non-monotonic concentration of SMX as a function of time under denitrification conditions, as well as those of Mohatt et al. (2011), under iron reducing conditions.
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•The molecular mechanisms of degradation of SMX under different redox were modelled.•Degradation of SMX is best modelled coupling various non-linear kinetic reactions.•Stable and unstable metabolites under different redox were considered in the model.•Some SMX metabolites were more ecologically toxic than the parent compound.
Microorganisms play a key role in nutrient cycling in agriculture and can contribute to improve soil quality and enhance crop production. Thus, there is a need to identify the most suitable ...management practices which foster increases in soil microbial biomass and diversity. A meta-analysis was performed to assess changes in microbial abundance in agricultural soils affected by: (i) management practices (tillage, fertilization and crop diversification); and (ii) environmental factors, including climate characteristics and soil properties. The scope of the meta-analysis was to evaluate whether microbial abundances are affected or not by organic fertilization or no fertilization, crop diversification (intercropping and crop rotations) and conservation tillage (reduced tillage/no-tillage) as an alternative to intensive conventional monocultures in agriculture. Only papers showing data on phospholipid fatty acids (PLFAs), providing indicators about soil microbial (total PLFA), fungal and bacterial biomass reached a critical mass to perform the meta-analysis. Therefore, soil microbial diversity could not be analyzed considering different management practices. Results showed that intercropping and crop rotations only significantly increased the abundance of fungi, with the corresponding increase in the fungal-to-bacterial ratio. Organic fertilization contributed to significant increases in bacterial and fungal abundance and total PLFA compared to mineral fertilization. Contrarily, the lack of fertilization negatively affected total PLFA, with no significant effect on bacterial and fungal abundances. Reduced tillage significantly increased total PLFA, fungal and bacterial abundances compared to conventional tillage, while no tillage had only a positive effect on fungi. Thus, as a general pattern, the adoption of sustainable management practices, mostly organic fertilization and reduced tillage, has overall positive effects on soil total microbial, fungal and bacterial abundance. These variables were not related to soil physicochemical properties and climatic factors, suggesting a positive global effect of sustainable management practices on soil microbial abundances. Thus, this study shows new insights by a meta-analysis of global studies about the effect of sustainable management practices on soil microbial abundances, needed for land-managers, policy-makers and farmers to select sustainable cropping systems that enhance microbial abundance.
•A meta-analysis was performed to assess microbial abundance in agricultural soils.•Sustainable management practices were assessed as alternative to conventional ones.•Only studies dealing with PLFAs provided indicators about soil microbial abundance.•Sustainable management practices had positive effects on soil microbial abundance.•Soil physicochemical properties and climatic factors did not affect the results.
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