Supporting Agricultural Extension: Could Farmers Contribute?

Is extension an effective tool for increasing social welfare? The objective of this study is to evaluate the feasibility of farmer financial participation in extension as an alternative to increase its efficiency. While extension costs have been high, the impact at farmers' welfare has not yielded the expected results. Rice production in Nigeria and Benin is used as a study case. Rice is an important food crop and cash crops and both countries have conditions to produce it locally. Two concepts are used to evaluate private participation: farmers' capability to pay (CTP) and requirement to pay (RTP) for extension. Farmers' capability to pay is evaluated from the expected increase benefit due to extension work. Requirement to pay is deducted from extension costs. Results show that rice farmers could initially contribute with 25% of the extension costs in Nigeria and 10% in Benin. While financial participation from farmers is a possibility, the role of the government is still needed to guarantee social welfare.Teaching/Communication/Extension/Profession, Q16, O3,

Farmer willingness to pay for seed-related information: rice varieties in Nigeria and Benin

"A typical private good is defined by its excludability and rivalry characteristics. Information embodied in a technology might not generate rivalry among its users. By contrast, excludability is certainly a characteristic of this kind of information and its delivery can generate incentives for private participation. This study examines farmers' preferences for seed of new rice varieties and their willingness to pay for seed-related information in villages of Nigeria and Benin. Conjoint analysis is used to estimate the structure of farmers' preferences for rice seed given a set of alternatives. Farmers are considered to be consumers of seed as a production input, preferring one variety over another based on the utility they obtain from its attributes, which depends on their own social and economic characteristics, including whether or not they sell rice. Contingent methods are used to elicit preferences and willingness to pay (WTP) for rice seed. The marginal values of attributes, with and without information about the seed, are estimated with an ordered probit regression. WTP for information is derived from the analysis of WTP for rice seed. The results have implications for the best way to finance research and extension services in the areas of intervention, particularly for new rice varieties. " Authors' AbstractWillingnes to pay (WTP), seed-related information, conjoint analysis, rice attributes, farmers' preferences, technology,

PRIVATE PARTICIPATION IN AGRICULTURAL EXTENSION IN NIGERIA AND BENIN: DETERMINING THE WILLINGNESS TO PAY FOR INFORMATION

A typical private good is defined by its excludability and rivalry characteristics. Information might not generate rivalry among its users. By contrast, excludability is certainly a characteristic of information and its delivery can generate incentives for private participation. This study examines farmers' preferences for seed of new rice varieties and their willingness to pay for related information in villages of Nigeria and Benin. Conjoint analysis is used to estimate the structure of farmers' preferences for rice seed given a set of alternatives. Farmers are considered to be maximizers of utility rather than profit, preferring one variety over another based on the utility they obtain from its attributes, which depends on their own social and economic characteristics. Contingent methods are used to elicit preferences and willingness to pay (WTP) for rice seed. The marginal values of attributes, with and without information about the seed, are estimated with an ordered probit regression. WTP for information is derived from the analysis of WTP for rice seed. The results have implications for the best way to finance research and extension services in the areas of intervention, particularly for new rice varieties.WTP for information, conjoint analysis, rice attributes, farmers' preferences, Teaching/Communication/Extension/Profession, O3, O33, C35,

Vibrational absorption sidebands in the Coulomb blockade regime of single-molecule transistors

Current-driven vibrational non-equilibrium induces vibrational sidebands in single-molecule transistors which arise from tunneling processes accompanied by absorption of vibrational quanta. Unlike conventional sidebands, these absorption sidebands occur in a regime where the current is nominally Coulomb blockaded. Here, we develop a detailed and analytical theory of absorption sidebands, including current-voltage characteristics as well as shot noise. We discuss the relation of our predictions to recent experiments.Comment: 7 pages, 6 figures; revised discussion of relation to experimen

Current-induced nonequilibrium vibrations in single-molecule devices

Finite-bias electron transport through single molecules generally induces nonequilibrium molecular vibrations (phonons). By a mapping to a Fokker-Planck equation, we obtain analytical scaling forms for the nonequilibrium phonon distribution in the limit of weak electron-phonon coupling $\lambda$ within a minimal model. Remarkably, the width of the phonon distribution diverges as $\sim\lambda^{-\alpha}$ when the coupling decreases, with voltage-dependent, non-integer exponents $\alpha$. This implies a breakdown of perturbation theory in the electron-phonon coupling for fully developed nonequilibrium. We also discuss possible experimental implications of this result such as current-induced dissociation of molecules.Comment: 7 pages, 4 figures; revised and extended version published in Phys. Rev.

Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Global maps of soil temperature.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications