Search results for "fertilization"
showing 10 items of 326 documents
Is the nuclear status of an embryo an independent factor to predict its ability to develop to term?
2012
Objective To determine the prognostic impact of the embryo nuclear status at day 2 among other major morphologic parameters (first cleavage at day 1, number of blastomeres and anuclear fragmentation at day 2) on the birth rate. Design Retrospective study. Setting Hospital IVF department. Patient(s) Women undergoing 1,629 day 2 transfers of 2,732 embryos from May 2006 to November 2008. Intervention(s) Four groups according to the embryo nuclear status. Main Outcome Measure(s) Implantation, miscarriage, and birth rates. Result(s) Univariate analysis indicated significantly higher birth rates when all blastomeres were mononucleated (15.0%) compared with embryos with not all blastomeres mononuc…
Selection of high potential embryos using time-lapse imaging: the era of morphokinetics.
2013
Incorporation of time-lapse imaging in the field of IVF has provided much information about embryo development. The combination of the embryo appearance (morphology) and the importance of when and how the cellular processes that lead to this appearance occur (kinetics) are now integrated into the unique concept of morphokinetics. At present, efforts are focused on using this information to improve embryo selection and existing success rates without losing sight of the ever-present objective of implementing a single ET strategy to avoid multiple gestations. Several investigative groups have identified predictive morphokinetic variables for embryo viability and implantation potential. Promisi…
A method for measuring mitochondrial mass and activity
2007
Mitochondria, responsible for the energy-generating process essential for the cell metabolism, differ for the number, localization and activity in animal cells and tissues in relation to the energetic needs. Using fluorescent probes specific for mitochondria, Mitotracker Green (MTG) and Orange (MTO), and Confocal Laser-Scanning Microscope (CLSM), we elaborated a method to measure in vivo the mitochondrial mass and activity, in sea urchin Paracentrotus lividus eggs and embryos. The analysis of captured images, revealed a variation of mitochondrial distribution and an increase of activity after fertilization.
Organic and chemical N fertilization on coriander (Coriandrum sativum L.)
2014
Coriander (Coriandrum sativum L.) is an annual herbaceous Medicinal and Aromatic Plant (MAP) dealing with a great industrial interest because of its strongly-scented fruits (“seeds”). The role of N fertilization in coriander seed yield is matter of debate as far; information is missing, for instance, about the effects of organic N fertilization, a mandatory technique when the organic cropping management is chosen. Organic and chemical N fertilizers have been supplied on coriander from 2001–2002 to 2006–2007 in a Mediterranean semi-arid environment, and their effects on the formation of biomass and seeds yield have been evaluated. Different organic fertilizers, allowed by EU regulations conc…
N use and partitioning in coriander (Coriandrum sativum L.) after organic and conventional N fertilization
2010
In coriander, a well known spice herb, many studies concerning the effect of N fertilization have been conducted in special areas where the cultivation of such plant has a major importance, such as India. Limited information is available as concerns the response of coriander to N fertilization under Mediterranean climatic conditions, above all when organic N fertilizers (mandatory when organic cropping management is chosen) are used. This work refers about some observations realised from 2004 to 2006 by an experiment on organic and mineral N fertilization techniques in coriander, carried on in the experimental farm “Sparacia” (Cammarata, AG, Sicily). Similarly to what suggested for other sp…
Nitrogen Use Efficiency and Nitrogen Fertilizer Recovery of Durum Wheat Genotypes as Affected by Interspecific Competition
2010
A better understanding of the genotype response to N fertilization under weed competition is necessary to identify varieties that exhibit high N use effi ciency even when weeds compete for available N. Such varieties may be more suitable for low input or organic systems. Th is study assessed the variations in nitrogen use effi ciency (NUE) (and its components) and the recovery of 15 N-labeled fertilizer in three durum wheat (Triticum durum Desf.) genotypes (one landrace and two varieties that diff er in terms of plant growth, grain yield potential, and adaptability to stressful environments) grown in the presence or absence of interspecifi c competition and varying soil N availability (0 or…
Nutrient removal by rice–wheat cropping system as influenced by crop establishment techniques and fertilization options in conjunction with microbial…
2020
AbstractNutrient uptake by the rice–wheat cropping system (RWCS) is an important indicator of soil fertility and plant nutrient status. The hypothesis of this investigation was that the rate and sources of nutrient application can differentially influence nutrient removal and soil nutrient status in different crop establishment techniques (CETs). Cropping system yield was on par in all the CETs evaluated, however, there were significant changes in soil nutrient availability and microbiological aspects. The system nitrogen (N), phosphorus (P), potassium (K) and zinc (Zn) uptake in aerobic rice system followed by zero tillage wheat (ARS-ZTW) was 15.7–17.6 kg ha−1, 0.7–0.9 kg ha−1, 7–9.8 kg ha…
Why France and India? The Convergence Hypothesis
2016
The cross-fertilization of insights derived from French and Indian intellectual history has ignited a pluridisciplinary reflection on the role played by these two countries in the fabric of the knowledge-based economy in the twenty-first century. On the one hand, the Age of Enlightenment in Western Europe in the eighteenth century, brought forward an autonomous position for knowledge in human societies, and, on the other hand, it was once predicted that India’s future would be built in her classrooms (Education Commission). Finally, we lay the ground for the characterization of a triple knowledge-based convergence between the two higher-education systems on academic, economic and institutio…
Vitrification of human mature oocytes in clinical practice.
2009
Oocyte cryopreservation has long been the focus of unsuccessful efforts to perfect its clinical application. Lately, vitrification has been shown to provide high degrees of success by different research groups. This review attempts to address the efficiency of oocyte vitrification in clinical practice through an analysis of reports of IVF cycles in which embryo transfers have been conducted with vitrified metaphase-II human oocytes.
Structure of mammalian plasma fetuin-B and its mechanism of selective metallopeptidase inhibition
2018
The co-crystal structure of the metallopeptidase astacin with its specific protein inhibitor fetuin-B reveals a novel mechanism of inhibition.