73 research outputs found
Agricultural productivity shocks, labour reallocation and rural-urban migration in China
This article analyses the way households in rural China use rural-urban migration and off-farm work as a response to negative productivity shocks in agriculture. I employ various waves of a longitudinal survey to construct a panel of individual migration and labour supply histories, and match them to detailed weather information, which I use to instrument agricultural productivity. For identification, I exploit the year-by-county variation in growing season rainfalls to explain within-individual changes in labour allocation. Data on days of work supplied to each sector allow to study the responses to weather shocks along both the participation and the intensive margin. Results suggest that farming is reduced by 4.5% and migration increased by about 5% in response to a 1 standard deviation negative rainfall shock. Increase in rural-urban migration derives from both longer spells in the city and from increment in the likelihood to participate in the urban sector. I find interesting heterogeneous response across generations driven by age-specific productivities in the different sectors and migration costs. Finally, land tenure insecurity seems to partially prevent households from freely reallocating labour away from farming in bad times.I wish to gratefully acknowledge financial support from the Ministerio EconomÃa y Competitividad (Spain), Maria de Maeztu grant (MDM 2014-0431), and the Comunidad de Madrid, MadEco-CM grant (S2015/HUM-3444).
News media and crime perceptions: evidence from a natural experiment
In democracies, voters rely on media outlets to learn about politically salient issues. This raises an important question: how strongly can media affect public perceptions? This paper uses a natural experiment - the staggered introduction of the Digital TV signal in Italy - to measure the effect of media persuasion on the perceptions individuals hold. We focus on crime perceptions and, combining channel-specific viewership and content data, we show that the reduced exposure to channels characterized by high levels of crime reporting decreases individual concerns about crime. The effect is driven by individuals aged 50 and over, who turn out to be more exposed to television while using other sources of information less frequently. Finally, we provide evidence about the effect of the digital introduction on public policies closely related to crime perceptions and on voting behaviourLuigi Minale acknowledges support from the Ministerio EconomÃa y Competitividad (Spain), MarÃa de Maeztu grant (MDM 2014-0431), Comunidad de Madrid, MadEco-CM (S2015/HUM-3444), and Fundación Ramón Areces
Constituents of the digestive gland of the molluscs of the genus - I. Novel diterpenes from
Dictyol A (I) and B (II; R = OH) and pachydictyol A (II; R = H) were isolated from the digestive glands of A. depilans. The structures of I and II (R = OH) were detd. from chem. and spectral data. I and II (R = OH) arose from feeding by A. depilans on the brown algae Dictyota dichotoma
The Unique 6-(p-Hydroxyphenyl)-2H-3,4-Dihydro-1,1-Dioxo-1,4-Thiazine and the New Tripeptide L-Glu-Gly-4-Hydroxystirylamine from the Marine Sponge Anchinoe tenacior
In our continuing search for bioactive compounds from marine organisms, we reported previously the isolation of a dimeric peptide alkaloid, anchinopeptolide A, from the Mediterranean sponge Anchinoe tenacior. Here we describe the isolation and structure elucidation of an unique metabolite 1, which incorporates a 1,1-dioxo-1,4 thiazine ring, and of a new tripeptide(2), from the sponge A. tenacior
Stereochemical assignment at C-24 and C-25 of marine 24-ethyl-26-hydroxy steroids through comparison with synthetic (24S,25S)-, (24S,25R)-, (24R,25R)-, and (24R,25S)-models
The four diastereoisomers of cyclostigmastanol I and their E-22-unsatd. derivs. were prepd. Anal. of 1H and 13C NMR spectra of the synthetic model compds. and of their α-methoxy-α-(trifluoromethyl)phenylacetates provided data suitable for the assignment of configuration at C-24 and C-25 in 24-ethyl-26-hydroxysteroids. The stereochem. (24S,25S) has been assigned to 24-ethyl-5β-cholestane-3α,4α,21,26-tetrol 3,21-disulfate (II), recently isolated from the marine ophiuroid Ophiolepis supereba
Polyoxygenated steroids of marine origin
A review, with 386 refs., on polyoxygenated steroids of marine origin, e.g. marine algae, Porifera, Coelenterata, Bryozoa, Mollusca, Echinodermata, Arthropoda, tunicates, and vertebrates (fish)
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