Classification of wild tomatoes: a review

Wild tomatoes are native to western South America. The generic status of wild tomatoes within the Solanaceae has been controversial since the eighteen century. Linnaeus in 1753 placed tomatoes in Solanum while Miller, a contemporary of Linnaeus, classified tomatoes in a new genus. The majority of later botanists have followed Miller. Differing numbers of species and conflicting supraspecific classifications have been proposed, based on morphology or crossing studies. Two major crossability groups have been identified, one that includes mainly self-compatible species that easily cross with the cultivated tomato, and another that comprises self-incompatible species not easily cross with the cultivated tomato. Recent molecular investigations using appropriate outgroups have shown that tomatoes and potatoes are close related phylogenetically, and support the inclusion of tomatoes within Solanum, the classification advocated here. We discuss the conflicting goals of classifications based on predictivity versus stability, a continuing controversy in systematics.Las especies de tomates silvestres son nativas del oeste de América de Sur. Su posición genérica dentro de las Solanáceas ha sido controvertida desde el Siglo XVIII. Linneo en 1753 ubico a los tomates en Solanum mientras que Miller, un contemponineo de Linneo, los incluyo dentro del nuevo genero Lycopersicon. Posteriormente, la mayoría de los botánicos siguieron la clasificación de Miller. Las clasificaciones basadas en morfología 0 en estudios de cruzamientos han propuesto diferente numero de especies 0 categorías supraespecíficas. Sobre la base de la cruzamientos entre especies se han identificado dos grupos; uno de ellos incluye especies autocompatibles que pueden cruzarse fácilmente con el tomate cultivado, el otro comprende especies autoincompatibles que no pueden cruzase fácilmente con esta especie. Recientes investigaciones moleculares, utilizando grupos externos adecuados, han mostrado que los tomates y las papas están muy relacionados filogenéticamente y apoyan la inclusión de los tomates dentro de Solanum, clasificación que hemos adoptado aquí. Se discute acerca del conflicto de los objetivos de las clasificaciones basados en la predicción 0 la estabilidad, una continua controversia en sistemática.Fil: Peralta, Iris Edith. University of Wisconsin; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Spooner, David M.. University of Wisconsin; Estados Unido

“Everyday” Knowledge and a New Paradigm of Animal Research

Commentary on Marino and Allen (2017) The Psychology of Cow

Attitudes of Canadian Pig Producers Toward Animal Welfare

As part of a larger study eliciting Canadian producer and non-producer views about animal welfare, open-ended, semi-structured interviews were used to explore opinions about animal welfare of 20 Canadian pig producers, most of whom were involved in confinement-based systems. With the exception of the one organic producer, who emphasized the importance of a ‘‘natural’’ life, participants attached overriding importance to biological health and functioning. They saw their efforts as providing pigs with dry, thermally regulated, indoor environments where animals received abundant feed, careful monitoring and where prospective disease outbreaks could be minimized and controlled. Emphasis was also placed on low-stress handling and agreeable working conditions which were believed to promote good animal care. The fact that pigs tend to respond to such conditions with steady growth reinforced the belief that good welfare was provided. Participants supported the use of sow gestation stalls, but with some reservations, and expressed concern about welfare problems that could occur if sows were grouped. Invasive procedures (castration, tail-docking, teeth clipping) were recognized as painful but were accepted because they were seen as: (1) necessary for sales or management; (2) satisfactory trade-offs to prevent worse welfare problems such as injury or infection; or (3) sufficiently short-term to be relatively unimportant. Participants were adamantly opposed to animal neglect and some welcomed actions of animal protectionists that expose poor care. Producers also welcomed natural-science-based approaches to improving animal welfare. The findings contribute to a broader effort to identify overlapping values among different stakeholder groups as a basis for formulating mutually agreeable, farm animal care and handling polices

Attitudes of Canadian Citizens Toward Farm Animal Welfare: A Qualitative Study

As part of a larger project to determine if there are animal-welfare-related values shared by some commercial food–animal producers and non-producers in Canada, open-ended, semi-structured interviews were conducted to elicit opinions about animal welfare among 24 urban and rural residents not involved in commercial animal production. All participants possessed a self-described interest in food animal well-being and were therefore assumed to represent the views of Canadian non-producers most apt to engage in efforts to shape the animal welfare policies of governments and businesses. Participants described animal welfare in moral or ethical terms, expressed virtually unanimous support for animals having access to “natural” living conditions, and (somewhat less often) linked animal welfare to positive affective states. Maintaining reasonable health and biological functioning was seen as important but was not to take precedence over the benefits of natural living. Participants favoured small family farms and unanimously objected to confinement housing. Participants did, however, offer qualified support for intensive practices and were unanimous in not assigning blame to producers, whom they regarded sympathetically. Predictably perhaps, given our sample, most were critical of industries preoccupied with profits and of consumers who unthinkingly seek cheap food. Recommended ways of improving welfare included instilling in consumers a greater appreciation for the intrinsic value of humanely reared animals, and better education of children regarding the connection between animals and food. Disagreements arose over the welfare implications of organic production and approaches to animal advocacy. Differing demographic backgrounds, experiential involvement with food animals and knowledge of food animal production practices may have influenced the nature or specificity of welfare concerns. Many participants admitted a lack of knowledge about contemporary production practices and some expressed an interest in obtaining additional knowledge. These findings contribute to a broader effort to identify shared values among different stakeholder groups as a basis for formulating widely acceptable, farm animal care and handling polices

Solanaceae—A Model for Linking Genomics With Biodiversity

Recent progress in understanding the phylogeny of the economically important plant family Solanaceae makes this an ideal time to develop models for linking the new data on plant genomics with the huge diversity of naturally occurring species in the family. Phylogenetics provides the framework with which to investigate these linkages but, critically, good species-level descriptive resources for the Solanaceae community are currently missing. Phylogeny in the family as a whole is briefly reviewed, and the new NSF Planetary Biodiversity Inventories project ‘PBI: Solanum—a worldwide treatment’ is described. The aims of this project are to provide species-level information across the global scope of the genus Solanum and to make this available over the Internet. The project is in its infancy, but will make available nomenclatural information, descriptions, keys and illustrative material for all of the approximately 1500 species of Solanum. With this project, the opportunity of linking valid, up-to-date taxonomic information about wild species of Solanum with the genomic information being generated about the economically important species of the genus (potato, tomato and eggplant) can be realized. The phylogenetic framework in which the PBI project is set is also of enormous potential benefit to other workers on Solanum. The community of biologists working with Solanaceae has a unique opportunity to effectively link genomics and taxonomy for better understanding of this important family, taking plant biology to a new level for the next century

Y₂Ti₂O₅S₂ – a promising n-type oxysulphide for thermoelectric applications

Thermoelectric materials offer an unambiguous solution to the ever-increasing global demand for energy by harnessing the Seebeck effect to convert waste heat to electrical energy. Mixed-anion materials are ideal candidate thermoelectric materials due to their thermal stability and potential for “phonon-glass, electron-crystal” behaviour. In this study, we use density-functional theory (DFT) calculations to investigate Y2Ti2O5S2, a cation-deficient Ruddlesden-Popper system, as a potential thermoelectric. We use hybrid DFT to calculate the electronic structure and band alignment, which indicate a preference for n-type doping with highly anisotropic in-plane and the out-of-plane charge-carrier mobilities as a result of the anisotropy in the crystal structure. We compute phonon spectra and calculate the lattice thermal conductivity within the single-mode relaxation-time approximation using lifetimes obtained by considering three-phonon interactions. We also calculate the transport properties using the momentum relaxation-time approximation to solve the electronic Boltzmann transport equations. The predicted transport properties and lattice thermal conductivity suggest a maximum in-plane ZT of 1.18 at 1000 K with a carrier concentration of 2.37 × 1020 cm−3. Finally, we discuss further the origins of the low lattice thermal conductivity, in particular exploring the possibility of nanostructuring to lower the phonon mean free path, reduce the thermal conductivity, and further enhance the ZT. Given the experimentally-evidenced high thermal stability and the favourable band alignment found in this work, Y2Ti2O5S2 has the potential to be a promising high-temperature n-type thermoelectric

Do potatoes and tomatoes have a single evolutionary history, and what proportion of the genome supports this history?

<p>Abstract</p> <p>Background</p> <p>Phylogenies reconstructed with only one or a few independently inherited loci may be unresolved or incongruent due to taxon and gene sampling, horizontal gene transfer, or differential selection and lineage sorting at individual loci. In an effort to remedy this situation, we examined the utility of conserved orthologous set (COSII) nuclear loci to elucidate the phylogenetic relationships among 29 diploid <it>Solanum </it>species in the sister clades that include tomato and potato, and in <it>Datura inoxia </it>as a far outgroup. We screened 40 COSII markers with intron content over 60% that are mapped in different chromosomes; selected a subset of 19 by the presence of single band amplification of size mostly between 600 and 1200 bp; sequenced these 19 COSII markers, and performed phylogenetic analyses with individual and concatenated datasets. The present study attempts to provide a fully resolved phylogeny among the main clades in potato and tomato that can help to identify the appropriate markers for future studies using additional species.</p> <p>Results</p> <p>Among potatoes, when total evidence is invoked, one single predominant history is highlighted with complete resolution within and among the three main clades. It also supports the hypothesis of the North and Central American B-genome origin of the tuber-bearing members of <it>Solanum </it>sect. <it>Petota </it>and shows a clear division between A genomes in clades 3 and 4, and B genomes in clade 1+2. On the other hand, when a prior agreement approach is invoked other potato evolutionary histories are revealed but with less support. These alternative histories could be explained by past hybridization, or fast rates of speciation. In the case of tomato, the analyses with all sequence data completely resolved 19 of 21 clades, for the first time revealed the monophyly of five clades, and gave further support for the recent segregation of new species from the former <it>Solanum peruvianum</it>. Concordance analyses revealed and summarized the extensive discordance among COSII markers. Some potential reasons for discordance could be methodological, to include systematic errors due to using a wrong model of sequence evolution, coupled with long branches, or mixtures of branch lengths within COSII, or undetected paralogy or alignment bias. Other reasons could be biological processes such as hybridization or lineage sorting.</p> <p>Conclusion</p> <p>This study confirms and quantifies the utility of using DNA sequences from different parts of the genome in phylogenetic studies to avoid possible bias in the sampling. It shows that 11–18 loci are enough to get the dominant history in this group of <it>Solanum</it>, but more loci would be needed to discern the distribution of gene genealogies in more depth, and thus detect which mechanism most likely shaped the discordance.</p

The proteasome cap RPT5/Rpt5p subunit prevents aggregation of unfolded ricin A chain

The plant cytotoxin ricin enters mammalian cells by receptor-mediated endocytosis, undergoing retrograde transport to the endoplasmic reticulum (ER) where its catalytic A chain (RTA) is reductively separated from the holotoxin to enter the cytosol and inactivate ribosomes. The currently accepted model is that the bulk of ER-dislocated RTA is degraded by proteasomes. We show here that the proteasome has a more complex role in ricin intoxication than previously recognised, that the previously reported increase in sensitivity of mammalian cells to ricin in the presence of proteasome inhibitors simply reflects toxicity of the inhibitors themselves, and that RTA is a very poor substrate for proteasomal degradation. Denatured RTA and casein compete for a binding site on the regulatory particle of the 26S proteasome, but their fates differ. Casein is degraded, but the mammalian 26S proteasome AAA-ATPase subunit RPT5 acts as a chaperone that prevents aggregation of denatured RTA and stimulates recovery of catalytic RTA activity in vitro. Furthermore, in vivo, the ATPase activity of Rpt5p is required for maximal toxicity of RTA dislocated from the Saccharomyces cerevisiae ER. Our results implicate RPT5/Rpt5p in the triage of substrates in which either activation (folding) or inactivation (degradation) pathways may be initiated

Paget's Osteosarcoma — no Cure in Sight

Purpose Paget' s osteosarcoma has a fearful reputation with a quoted survival of at best 5% at 5 years.We therefore reviewed our experience of 26 patients treated over the last 25 years using modern staging and limb salvage techniques to see if there had been any improvement in survival

"Everyday" Knowledge and a New Paradigm of Animal Research

Commentary on Marino and Allen (2017) The Psychology of Cow