77 research outputs found
The domestication syndrome in Phoenix dactylifera seeds : toward the identification of wild date palm populations
Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm(Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a "wild" reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops
Progress in Classical and Quantum Variational Principles
We review the development and practical uses of a generalized Maupertuis
least action principle in classical mechanics, in which the action is varied
under the constraint of fixed mean energy for the trial trajectory. The
original Maupertuis (Euler-Lagrange) principle constrains the energy at every
point along the trajectory. The generalized Maupertuis principle is equivalent
to Hamilton's principle. Reciprocal principles are also derived for both the
generalized Maupertuis and the Hamilton principles. The Reciprocal Maupertuis
Principle is the classical limit of Schr\"{o}dinger's variational principle of
wave mechanics, and is also very useful to solve practical problems in both
classical and semiclassical mechanics, in complete analogy with the quantum
Rayleigh-Ritz method. Classical, semiclassical and quantum variational
calculations are carried out for a number of systems, and the results are
compared. Pedagogical as well as research problems are used as examples, which
include nonconservative as well as relativistic systems
Colour assessment outcomes â a new approach to grading the severity of color vision loss
INTRODUCTION: Recent studies have shown that a significant percentage of subjects with anomalous, congenital trichromacy can perform the suprathreshold, colour-related tasks encountered in many occupations with the same accuracy as normal trichromats. In the absence of detailed, occupation-specific studies, an alternative approach is to make use of new findings and the statistical outcomes of past practices that have been considered safe to produce graded, justifiable categories of colour vision that can be enforced.
METHODS: We analyzed traditional color assessment outcomes and measured severity of colour vision loss using the CAD test in 1363 subjects (336 normals, 705 deutan, 319 protan and 3 tritan). The severity of colour vision loss was measured in each subject and statistical, pass / fail outcomes established for each of the most commonly used, conventional colour assessment tests and protocols.
RESULTS: The correlation between the number of Ishihara (IH) test plates subjects fail and the severity of RG colour vision loss was very poor. The 38 plates IH test has high sensitivity when no errors are allowed (i.e., only 0.71% deutans and 0.63% protans pass). Protocols based on zero errors are uncommon since 18.15% of normal trichromats fail. The most common protocols employ either the 24 or the 14 plates editions with two or less errors. These protocols pass almost all normal trichromats, but the deutans and some protans that also pass (when two or less errors are allowed) can be severely deficient. This is simply because the most challenging plates have not been included in the 24 and 14 plates editions. As a result, normals no longer fail, but the deutans and protans that pass have more severe loss of colour vision since they fail less challenging plates. The severity of colour vision loss was measured in each subject and statistical, pass / fail outcomes established for each of the most commonly used, conventional colour assessment tests and protocols.
DISCUSSION: Historical evidence and new findings that relate severity of loss to the effective use of colour signals in a number of tasks provide the basis for a new colour grading system based on six categories. A single colour assessment test is needed to establish the applicantâs Colour Vision category which can range from âsupernormalâ (CV0), for the most stringent, colour-demanding tasks, to âsevere colour deficiencyâ, when red / green colour vision is either absent or extremely weak (CV5)
Searching for the origins of bere barley: a geometric morphometric approach to cereal landrace recognition in archaeology
Bere is a landrace of barley, adapted to the marginal conditions of northern Scotland, especially those of the Northern and Western Isles. The history of bere on these islands is long and, in an era of diminishing landrace cultivation, bere now represents one of the oldest cereal landraces in Europe still grown commercially. The longevity of bere raises the possibility of using grain characteristics of present-day specimens to identify bere in the archaeological record. Geometric modern morphometric (GMM) analysis of grains from bere and other barley landraces is conducted to determine whether landraces can be differentiated on grain morphology. Results indicate that there are morphological differences between bere and other British and Scandinavian landraces, and between bere from Orkney and the Western Isles, both of which are apparent in genetic analysis. This finding paves the way for the identification of bere archaeologically, helping to establish its status as living heritage and securing its commercial future. More broadly, this work indicates the potential of grain GMM for the recognition of cereal landraces, permitting the ancestry and exchange of landraces to be traced in the archaeological record
First finds of Prunus domestica L. in Italy from the Phoenician and Punic periods (6th-2nd centuries BC)
Abstract During the archaeological excavations in the Phoenician and Punic settlement of Santa Giusta (Oristano, Sardinia, Italy), dating back to the 6thâ2nd centuries bc, several Prunus fruitstones (endocarps) inside amphorae were recovered. The exceptional state of preservation of the waterlogged remains allowed morphometric measurements to be done by image analysis and statistical comparisons made with modern cultivated and wild Prunus samples collected in Sardinia. Digital images of modern and archaeological Prunus fruitstones were acquired with a flatbed scanner and analysed by applying image analysis techniques to measure 26 morphometric features. By applying stepwise linear discriminant analysis, a morphometric comparison was made between the archaeological fruitstones of Prunus and the modern ones collected in Sardinia. These analyses allowed identification of 53 archaeological fruitstones as P. spinosa and 11 as P. domestica. Moreover, the archaeological samples of P. spinosa showed morphometric similarities in 92.5% of the cases with the modern P. spinosa samples currently growing near the Phoenician and Punic site. Likewise, the archaeological fruitstones identified as P. domestica showed similarities with the modern variety of P. domestica called Sanguigna di Bosa which is currently cultivated near the village of Bosa. Currently, these findings represent the first evidence of P. domestica in Italy during the Phoenician and Punic periods. Keywords Archaeobotany · Image analysis · Morphometric features · Prunus · Sardini
BMC Public Health
BACKGROUND: Population health intervention research raises major conceptual and methodological issues. These require us to clarify what an intervention is and how best to address it. This paper aims to clarify the concepts of intervention and context and to propose a way to consider their interactions in evaluation studies, especially by addressing the mechanisms and using the theory-driven evaluation methodology. MAIN TEXT: This article synthesizes the notions of intervention and context. It suggests that we consider an "interventional system", defined as a set of interrelated human and non-human contextual agents within spatial and temporal boundaries generating mechanistic configurations - mechanisms - which are prerequisites for change in health. The evaluation focal point is no longer the interventional ingredients taken separately from the context, but rather mechanisms that punctuate the process of change. It encourages a move towards theorization in evaluation designs, in order to analyze the interventional system more effectively. More particularly, it promotes theory-driven evaluation, either alone or combined with experimental designs. CONCLUSION: Considering the intervention system, hybridizing paradigms in a process of theorization within evaluation designs, including different scientific disciplines, practitioners and intervention beneficiaries, may allow researchers a better understanding of what is being investigated and enable them to design the most appropriate methods and modalities for characterizing the interventional system. Evaluation methodologies should therefore be repositioned in relation to one another with regard to a new definition of "evidence", repositioning practitioners' expertise, qualitative paradigms and experimental questions in order to address the intervention system more profoundly
Archaeobotany, vine growing and wine producing in Roman Southern France:the site of Gasquinoy (BĂ©ziers, HĂ©rault)
International audienceUnequivocal evidence of Roman vine cultivation and wine making is provided from studies of combinedarchaeological remains from the site of Gasquinoy (Southern France). Waterlogged and charred plantmaterial (fruits/seeds/wood) collected from wells located in the close vicinity of cultivated ïŹelds andwine making establishments conïŹrms the local signiïŹcance of this activity. The results offer insights onparticular aspects of wine production (âtraumaticâ treading of grapes and straining) and provide evidenceof secondary agricultural activities such as cereal production and fruit tree cultivation. The potential useof monocotyledonous stems such as Arundo/Phragmites in the farming system is discussed
Argumentaire pour une utilisation plus large de la photochimiothĂ©rapie extracorporelle chez lâenfant
International audienceThe management of immune diseases in children remains challenging , although significant advances have been made. In addition to pharmacological approaches, extracorporeal photochemotherapy (ECP) is distinctive in its ability to provide immunomodulation without immune suppression or toxicity. However, in practice, this therapy is not widely used because of logistical issues and the lack of robust clinical pediatric studies. Here, we discuss the potential clinical applications of ECP in children and emphasize the need for a rigorous and specifically pediatric clinical evaluation of ECP. à 2010 Elsevier Masson SAS. All rights reserved. Résumé Malgré l'apport des biothérapies, le traitement des maladies dysim-munitaires sévÚres et des conflits allogéniques de l'enfant reste difficile et entaché de nombreuses complications. Dans ce contexte, la photo-chimiothérapie extracorporelle (PCE) (thérapie cellulaire qui repose sur l'effet immunomodulateur des cellules mononucléées du patient, prélevées par aphérÚse et exposées ex vivo aux rayons ultraviolets A [UVA] en présence de psoralÚne) a l'avantage notable d'induire une tolérance immunitaire sans générer d'immunosuppression systémique ni de toxicité a ` court, moyen ou long terme. Cette immunomodulation fait intervenir notamment la génération de lymphocytes T régulateurs (T reg). Malgré cela, la PCE est peu utilisée en raison de ses contraintes logistiques et du manque de données cliniques. Nous proposons une revue des indications reconnues et potentielles de la PCE en pédiatrie. Nous insistons sur la nécessité d'une e Žvaluation clinique spécifique a ` l'enfant qui ne peut se concevoir sans la participation active des cliniciens pédiatres en particulier dans le domaine de la transplanta-tion et des maladies auto-immunes et inflammatoires
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