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1.
Chem Biodivers ; 21(4): e202301860, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38403856

ABSTRACT

The males-produced pheromone blend of the Mormidea v-luteum (Hemiptera, Pentatomidae) consists in two isomers of zingiberenol (1) and three of murgantiol (2). While the absolute configuration of the zingiberenol isomers has been described, the configurations of the murgantiol isomers remained unexplored. So, our objective was to identify the absolute configuration of the murgantiol isomers (2 a-c) in the pheromone blend. To achieve this, we initially performed dehydration of the natural extract followed by enantiomeric resolution and, as a result, the three isomers was identified as (4R,1'S)-murgantiol. By leveraging the fixed cis and trans relationships among all pheromone components, we established the configuration at C-1 for isomers 2 a and 2 b is S, while that of 2 c is R. Finally, employing microchemical Sharples asymmetric dihydroxylation and epoxide ring closure, we determined the absolute configuration of the epoxide ring. Consequently, the natural isomers 2 a, 2 b, and 2 c were identified as (1S,4R,1'S,4'R)-, (1S,4R,1'S,4'S)-, and (1R,4R,1'S,4'S)-murgantiol, respectively.


Subject(s)
Hemiptera , Heteroptera , Oryza , Sesquiterpenes , Male , Animals , Pheromones , Stereoisomerism , Epoxy Compounds
2.
R Soc Open Sci ; 8(5): 202117, 2021 May 05.
Article in English | MEDLINE | ID: mdl-34035947

ABSTRACT

The vast amount of research devoted to public goods games has shown that contributions may be dramatically affected by varying framing conditions. This is particularly relevant in the context of donations to charities and non-governmental organizations. Here, we design a multiple public goods experiment by introducing five types of funds, each differing in the fraction of the contribution that is donated to a charity. We found that people contribute more to public goods when the associated social donations are presented as indirect rather than as direct donations. At the same time, the fraction of the donations devoted to charity is not affected by the framing. We have also found that, on average, women contribute to public goods and donate to charity significantly more than men. These findings are of potential interest to the design of social investment tools, in particular for charities to ask for better institutional designs from policy makers.

3.
J Endocrinol Invest ; 44(7): 1363-1377, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33501614

ABSTRACT

Cadmium (Cd), a highly toxic heavy metal, is found in soil, environment and contaminated water and food. Moreover, Cd is used in various industrial activities, such as electroplating, batteries production, fertilizers, while an important non-occupational source is represented by cigarette smoking, as Cd deposits in tobacco leaves. Since many years it is clear a strong correlation between Cd body accumulation and incidence of many diseases. Indeed, acute exposure to Cd can cause inflammation and affect many organs such as kidneys and liver. Furthermore, the attention has focused on its activity as environmental pollutant and endocrine disruptor able to interfere with metabolic and energy balance of living beings. Both in vitro and in vivo experiments have demonstrated that the Cd-exposure is related to metabolic diseases such as obesity, diabetes and osteoporosis even if human studies are still controversial. Recent data show that Cd-exposure is associated with atherosclerosis, hypertension and endothelial damage that are responsible for cardiovascular diseases. Due to the large environmental diffusion of Cd, in this review, we summarize the current knowledge concerning the role of Cd in the incidence of metabolic and cardiovascular diseases.


Subject(s)
Cadmium/adverse effects , Endocrine Disruptors/adverse effects , Metabolic Diseases/physiopathology , Humans , Metabolic Diseases/etiology
4.
J Chem Ecol ; 43(6): 550-556, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28601940

ABSTRACT

The nitidulid beetle Lobiopa insularis is an important pest of strawberry crops in the United States and Brazil. Both larvae and adults feed on ripe strawberries, causing 20-70% loss in production during serious infestations. Aiming at the development of efficient, clean, and highly specific pest management systems, semiochemicals, especially pheromones, are particularly useful. Analyses of the extracts of both males and females obtained from aeration of live beetles showed the presence of three male specific compounds, 2-nonanone, 2-undecanone, and 2-undecanol (in an enantiomeric ratio of S:R = 3.5:1). This is the first record of ketones and an alcohol as pheromone components in Nitidulidae. These compounds were emitted by males in amounts of 0.3:6:1.5 ng per insect within 24 h (1:30:3), respectively, during the scotophase, indicating nocturnal sexual activity. Field tests with pitfall traps containing different mixtures of compounds and ripe strawberries as a co-attractant summed up to five treatments with 25 replications. As a result, 59% males and 41% females (1:0.7) were caught, indicating the L. insularis pheromone to cause aggregation of both sexes. Results of the field tests showed that the attractivity of the binary mixture of ketones (T3) differed from the control (T5), from traps with 2-undecanone alone (T4), and from the mixture of 2-undecanone and racemic 2-undecanol (T2). Moreover, the activity of the ternary mixture of compounds (T1) was not different from that of T3, indicating that the racemic alcohol did not positively influence trap catches. In future applications, a mixture of synthetic strawberry-derived compounds that are attractive to L. insularis may substitute rapidly decaying fruit in the field, maintaining catches for longer periods. Because of its efficiency and low cost, a mixture of 2-undecanone and 2-nonanone is recommended to catch adult L. insularis in the field.


Subject(s)
Behavior, Animal , Coleoptera/chemistry , Coleoptera/physiology , Pheromones/chemistry , Volatile Organic Compounds/chemistry , Animals , Fatty Alcohols/chemistry , Female , Fragaria , Gas Chromatography-Mass Spectrometry , Humans , Ketones/chemistry , Larva/physiology , Male , Pheromones/physiology , Spectroscopy, Fourier Transform Infrared
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(3 Pt 2): 037101, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23031054

ABSTRACT

Spatially embedded networks are important in several disciplines. The prototypical spatial network we assume is the Random Geometric Graph, of which many properties are known. Here we present new results for the two-point degree correlation function in terms of the clustering coefficient of the graphs for two-dimensional space in particular, with extensions to arbitrary finite dimensions.


Subject(s)
Algorithms , Models, Statistical , Computer Simulation
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