THE INCREASING ROLE OF AGRIBUSINESS IN AGRICULTURAL ECONOMICS

While the demand for traditional agricultural economics is diminishing, there is a growing need for the economics and management of the food sector and the environment. Departments of agricultural economics have shown great flexibility in including agribusiness in their Bachelor's and Master's teaching programs. Ph.D and research programs appear to adjust more slowly to changing demand. Although agricultural economics programs are providing a variety of service course offerings, opportunities for joint programs with biological, physical, and natural sciences, particularly resource management, are not being exploited. If business schools decide to compete for agribusiness students in the future, missed opportunities with other departments and schools may become very costly. If this profession is to remain viable in the long run, it must continue to evolve, developing opportunities with biological, physical, and natural disciplines, in order to meet the demands of a changing market.agribusiness, agricultural economics, education, extension, research, Agribusiness, Teaching/Communication/Extension/Profession,

Comment on "The origin of eucrites, diogenites, and olivine diogenites: magma ocean crystallization and shallow magma processes on Vesta" by B.E. Mandler and L.T. Elkins-Tanton

International audienceMandler and Elkins-Tanton () recently proposed an upgraded magma ocean model for the differentiation history of the giant asteroid 4 Vesta. They show that a combination of both equilibrium crystallization and fractional crystallization processes can reproduce the major element compositions of eucritic melts and broadly the range of mineral compositions observed in diogenites. They assert that their model accounts for all the howardites, eucrites, and diogenites (HEDs), and use it to predict the crustal thickness and the proportions of the various lithologies. Here, we show that their model fails to explain the trace element diversity of the diogenites, contrary to their claim. The diversity of the heavy REE enrichment exhibited by the orthopyroxenes in diogenites is inconsistent with crystallization of these cumulates in either shallow magma chambers replenished by melts from a magma ocean or in a magma ocean. Thus, proportions of the various HED lithologies and the crustal thickness predicted from this model are not necessarily valid

Evidence for K-rich terranes on Vesta from impact spherules

International audienceThe howardite-eucrite-diogenite (HED) clan is a group of meteorites that probably originate from the asteroid Vesta. Some of them are complex breccias that contain impact glasses whose compositions mirror that of their source regions. Some K-rich impact glasses (up to 2 wt% K2O) suggest that in addition to basalts and ultramafic cumulates, K-rich rocks are exposed on Vesta's surface. One K-rich glass (up to 6 wt% K2O), with a felsic composition, provides the first evidence of highly differentiated K-rich rocks on a large asteroid. They can be compared to the rare lunar granites and suggest that magmas generated in a large asteroid are more diverse than previously thought

Posteucritic magmatism on Vesta: Evidence from the petrology and thermal history of diogenites

International audienceWe report on the petrology and the thermal histories of 13 diogenites in order to constrain the formation processes of the Vestan crust. We classify diogenites into unequilibrated and equilibrated diogenites in a scheme similar to that for basaltic eucrites. Pyroxenes in unequilibrated diogenites are chemically zoned, indicating that they crystallized rapidly from melts and escaped from global crustal metamorphism. The presence of unequilibrated diogenites casts doubt on the fact that all the diogenites formed at depth in the parent body, as commonly thought. Some diogenites probably crystallized in shallow intrusions or were extruded on the surface. These facts strengthen the geochemical evidence that diogenites and eucrites are not directly cogenetic and suggest that at least some diogenites have intruded the early formed eucritic crust. Thus, diogenites are certainly not the products of the crystallization of the magma ocean that triggered the differentiation of Vesta but are more likely cumulates associated with a later stage of magmatism. Furthermore, the intrusion of diogenites could have significantly thickened the early formed crust, making it difficult to excavate deep‐seated olivine mantle by moderate impact events

The Epstein-Barr Virus Episome Maneuvers between Nuclear Chromatin Compartments during Reactivation.

The human genome is structurally organized in three-dimensional space to facilitate functional partitioning of transcription. We learned that the latent episome of the human Epstein-Barr virus (EBV) preferentially associates with gene-poor chromosomes and avoids gene-rich chromosomes. Kaposi's sarcoma-associated herpesvirus behaves similarly, but human papillomavirus does not. Contacts on the EBV side localize to OriP, the latent origin of replication. This genetic element and the EBNA1 protein that binds there are sufficient to reconstitute chromosome association preferences of the entire episome. Contacts on the human side localize to gene-poor and AT-rich regions of chromatin distant from transcription start sites. Upon reactivation from latency, however, the episome moves away from repressive heterochromatin and toward active euchromatin. Our work adds three-dimensional relocalization to the molecular events that occur during reactivation. Involvement of myriad interchromosomal associations also suggests a role for this type of long-range association in gene regulation.IMPORTANCE The human genome is structurally organized in three-dimensional space, and this structure functionally affects transcriptional activity. We set out to investigate whether a double-stranded DNA virus, Epstein-Barr virus (EBV), uses mechanisms similar to those of the human genome to regulate transcription. We found that the EBV genome associates with repressive compartments of the nucleus during latency and with active compartments during reactivation. This study advances our knowledge of the EBV life cycle, adding three-dimensional relocalization as a novel component to the molecular events that occur during reactivation. Furthermore, the data add to our understanding of nuclear compartments, showing that disperse interchromosomal interactions may be important for regulating transcription

A practical approach to estimate resting energy expenditure in frail elderly people

Objectives: Some prediction equations of resting energy expenditure (REE) are available and can be used in clinical wards to determine energy requirements of patients. The aim of the present study was to assess the accuracy of those equations in sick elderly patients, using the Bland & Altman methods with our database of 187 REE measurements.Design: The 3 equations tested were Harris & Benedict equation of 1919, WHO/FAO/UNU equation of 1985 and Fredrix et al. equation of 1990. In addition, three models developed from the present data were tested.Results: The present study shows that the Fredrix et al equation gave an accurate prediction of REE without significant bias along the whole range of REE. It also shows that under-weight sick elderly patients (BMI ≤ 21 kg/m2) had a greater weight-adjusted REE than their normal weight counterparts.Conclusion: A simple formula using a factor multiplying body weight, i.e. 22 kcal/kg/d in under-weight and 19 kcal/kg/d in normal weight sick elderly was accurate to predicting REE and bias was not influenced by the level of REE. This model included half of the group in the range of ±10% of the difference between predicted REE and measured REE, but the confidence interval of the bias was ±400 kcal/d. Conversely, the Harris & Benedict and WHO formulae did accurately predict REE

Tangle-bearing neurons survive despite disruption of membrane integrity in a mouse model of tauopathy

Neurofibrillary tangles (NFTs) are associated with neuronal loss and correlate with cognitive impairment in Alzheimer disease, but how NFTs relate to neuronal death is not clear. We studied cell death in Tg4510 mice that reversibly express P301L mutant human tau and accumulate NFTs using in vivo multiphoton imaging of neurofibrillary pathology, propidium iodide (PI) incorporation into cells, caspase activation and DNA labeling. We first observed that in live mice a minority of neurons was labeled with the caspase probe or with PI fluorescence. These markers of cell stress were localized in the same cells and appeared to be specifically within NFT-bearing neurons. Contrary to expectations, the PI-stained neurons did not die over a day of observation; the presence of Hoechst-positive nuclei in them on the subsequent day indicated that the NFT-associated membrane disruption suggested by PI staining and caspase activation do not lead to acute death of neurons in this tauopathy model. This unique combination of in vivo multiphoton imaging with markers of cell death and pathologic alteration is a powerful tool for investigating neuronal damage associated with neurofibrillary pathology

Growth inhibition of cytosolic Salmonella by caspase-1 and caspase-11 precedes host cell death

Sensing bacterial products in the cytosol of mammalian cells by NOD-like receptors leads to the activation of caspase-1 inflammasomes, and the production of the pro-inflammatory cytokines interleukin (IL)-18 and IL-1β. In addition, mouse caspase-11 (represented in humans by its orthologs, caspase-4 and caspase-5) detects cytosolic bacterial LPS directly. Activation of caspase-1 and caspase-11 initiates pyroptotic host cell death that releases potentially harmful bacteria from the nutrient-rich host cell cytosol into the extracellular environment. Here we use single cell analysis and time-lapse microscopy to identify a subpopulation of host cells, in which growth of cytosolic Salmonella Typhimurium is inhibited independently or prior to the onset of cell death. The enzymatic activities of caspase-1 and caspase-11 are required for growth inhibition in different cell types. Our results reveal that these proteases have important functions beyond the direct induction of pyroptosis and proinflammatory cytokine secretion in the control of growth and elimination of cytosolic bacteria