Calcium ion currents mediating oocyte maturation events

During maturation, the last phase of oogenesis, the oocyte undergoes several changes which prepare it to be ovulated and fertilized. Immature oocytes are arrested in the first meiotic process prophase, that is morphologically identified by a germinal vesicle. The removal of the first meiotic block marks the initiation of maturation. Although a large number of molecules are involved in complex sequences of events, there is evidence that a calcium increase plays a pivotal role in meiosis re-initiation. It is well established that, during this process, calcium is released from the intracellular stores, whereas less is known on the role of external calcium entering the cell through the plasma membrane ion channels. This review is focused on the functional role of calcium currents during oocyte maturation in all the species, from invertebrates to mammals. The emerging role of specific L-type calcium channels will be discussed

Variability and trait‐specific accessions for grain yield and nutritional traits in germplasm of little millet ( Panicum sumatrense Roth. Ex. Roem. & Schult.)

Little millet (Panicum sumatrense Roth. Ex. Roem. & Schult.), a member of the grass family Poaceae, is native to India. It is nutritionally superior to major cereals, grows well on marginal lands, and can withstand drought and waterlogging conditions. Two-hundred diverse little millet landraces were characterized to assess variability for agronomic and nutritional traits and identify promising accessions. Highly significant variabilitywas found for all the agronomic and grain nutrient traits. Accessions of robusta were high yielding whereas those of nana were rich in grain nutrients. About 80% of the accessions showed consistent protein and zinc (Zn) contents whereas iron (Fe) and calcium (Ca) contents were less consistent (29.5 and 63.5%, respectively) over 2 yr. Promising trait-specific accessions were identified for greater seed weight (10 accessions), high grain yield (15), high biomass yield (15), and consistently high grain nutrients (30) over 2 yr (R2 = .69–.74, P ≤ .0001). A few accessions showed consistently high for two or more nutrients (IPmr 449 for Fe, Zn, Ca, and protein; IPmr 981 for Zn and protein). Five accessions (IPmr 855, 974, 877, 897, 767) were high yielding and also rich in Ca. Consumption of 100 g of little millet grains can potentially contribute to the recommended dietary allowance of up to 28% Fe, 37% Zn, and 27% protein. Multilocation evaluation of the promising accessions across different soil types, fertility levels, and climatic conditions would help to identify valuable accessions for direct release as a cultivar or use in little millet improvement

North American Wild Relatives of Grain Crops

The wild-growing relatives of the grain crops are useful for long-term worldwide crop improvement research. There are neglected examples that should be accessioned as living seeds in gene banks. Some of the grain crops, amaranth, barnyard millet, proso millet, quinoa, and foxtail millet, have understudied unique and potentially useful crop wild relatives in North America. Other grain crops, barley, buckwheat, and oats, have fewer relatives in North America that are mostly weeds from other continents with more diverse crop wild relatives. The expanding abilities of genomic science are a reason to accession the wild species since there are improved ways to study evolution within genera and make use of wide gene pools. Rare wild species, especially quinoa relatives in North American, should be acquired by gene banks in cooperation with biologists that already study and conserve at-risk plant populations. Many of the grain crop wild relatives are weeds that have evolved herbicide resistance that could be used in breeding new herbicide-resistant cultivars, so well-documented examples should be accessioned and also vouchered in gene banks

Basic fluid system trainer

This invention, a trainer mounted and housed within a mobile console, is used to teach and reinforce fluid principles to students. The system trainer has two centrifugal pumps, each driven by a corresponding two-speed electric motor. The motors are controlled by motor controllers for operating the pumps to circulate the fluid stored within a supply tank through a closed system. The pumps may be connected in series or in parallel. A number of valves are also included within the system to effect different flow paths for the fluid. In addition, temperature and pressure sensing instruments are installed throughout the closed system for measuring the characteristics of the fluid, as it passes through the different valves and pumps. These measurements are indicated on a front panel mounted to the console, as a teaching aid, to allow the students to observe the characteristics of the system

Adaptation des systèmes de production agricole aux changements de contexteenvironnemental, agricole et social, et place des légumineuses dans la transitionagroécologique

In the Bourgogne-Franche-Comté and Auvergne-Rhône-Alpes regions, the PSDR4 projects POEETE andProSys dealt with the adaptation of agricultural production systems to changes in the environmental,agricultural and social context, focusing on different scales and taking into account the context of reducedinputs and the search for autonomy by introducing legume crops. The processed data come from various approaches: surveys, experimental monitoring, modelling approach... The impact of climate change onthe ecophysiology of legume crops was addressed through a model plant, the pea, and two criteria:flowering date and frost stress. To ensure the sustainability of mixed farming operations, new foragemixtures have been tested. Then the ecosystemic services provided by legume crops were studied:precedent effect, nitrogen content and interest in improving the protein autonomy of farms. Theprioritization of ecosystem services in the adoption of these crops was studied via surveys of pioneerfarmers in the region. Finally, the agroecological transition was studied via questions about thecomplementarity of mixed farming and livestock production, the performance of cropping systemsincluding legume crops, farmers’ motivations to develop more agro-ecological practices and the study ofmodel farm trajectories.Les projets PSDR4 POEETE et ProSys traitaient de l’adaptation des systèmes de production agricoleaux changements de contexte environnemental, agricole et social, en régions Bourgogne-Franche-Comtéet Auvergne-Rhône-Alpes, en s’intéressant aux différentes échelles et en prenant en compte le contextede la diminution des intrants et de la recherche d’autonomie. Les données traitées sont issuesd’approches variées : enquêtes, suivis expérimentaux, modélisation… L’impact du changementclimatique sur l’écophysiologie des légumineuses a été abordé au travers d’une plante modèle, le pois,et de deux critères : la date de floraison et le stress lié au gel. Pour assurer la durabilité des exploitationsen polyculture-élevage, de nouveaux mélanges fourragers ont été testés. Puis les servicesécosystémiques rendus par les légumineuses ont été étudiés : effet précédent, teneur en azote et intérêtde leur introduction dans une démarche d’amélioration de l’autonomie protéique des exploitations. Desenquêtes auprès des agriculteurs pionniers en région ont permis de réaliser une hiérarchisation desservices écosystémiques lors de l’adoption de ces cultures. Enfin la transition agroécologique a étéétudiée via des questionnements autour de la complémentarité entre polyculture et élevage, desperformances des systèmes de culture incluant des légumineuses, des motivations des agriculteurs pourdévelopper des pratiques plus agroécologiques et l’étude de trajectoires d’exploitations modèles