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See detailFerroelectricity and tetragonality in ultrathin PbTiO3 films
Lichtensteiger, C.; Triscone, J. M.; Junquera, J. et al

in Physical Review Letters (2005), 94

The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 Angstrom. High resolution x ray pointed out a ... [more ▼]

The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 Angstrom. High resolution x ray pointed out a systematic decrease of the c-axis lattice parameter with decreasing film thickness below 200 Angstrom. Using a first-principles model Hamiltonian approach, the decrease in tetragonality is related to a reduction of the polarization attributed to the presence of a residual unscreened depolarizing field. It is shown that films below 50 Angstrom display a significantly reduced polarization but still remain ferroelectric. [less ▲]

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See detailFerroelectricity in PbTiO3 thin films: A first principles approach
Rabe, K. M.; Ghosez, Philippe ULg

in Journal of Electroceramics (2000), 4(2-3), 379-383

The ground-state ferroelectric distortion of PbTiO3 thin films is studied using a first-principles effective Hamiltonian to describe the structural energetics at a microscopic level. Under short-circuit ... [more ▼]

The ground-state ferroelectric distortion of PbTiO3 thin films is studied using a first-principles effective Hamiltonian to describe the structural energetics at a microscopic level. Under short-circuit electrical and zero-stress mechanical boundary conditions, (0 0 1) films as thin as one unit cell are found to support a stable perpendicular polarization. Size effects in the layer-by-layer ferroelectric distortion are discussed. The continuum limit of the first-principles effective Hamiltonian has the same form as the widely-used Landau-Ginzburg expression for the free energy near T-c, so that the present results can be directly related to those of previous phenomenological studies. In particular, a microscopic interpretation of the extrapolation length delta is proposed. [less ▲]

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See detailFerroelectricity in ultrathin film capacitors
Lichtensteiger, C.; Zubko, P.; Stengel, M. et al

in Oxide Ultrathin Films: Science and Technology (2012)

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See detailFerrokinetic measurement of erythropoiesis.
Beguin, Yves ULg; Stray, S. M.; Cazzola, M. et al

in Acta Haematologica (1988), 79(3), 121-6

Ferrokinetic measurements have proved useful because of the dominant role of the erythron in tissue iron uptake. Detailed measurements of the plasma iron disappearance curve coupled with in vivo counting ... [more ▼]

Ferrokinetic measurements have proved useful because of the dominant role of the erythron in tissue iron uptake. Detailed measurements of the plasma iron disappearance curve coupled with in vivo counting have defined the major pathways of iron utilization and early refluxes of iron into plasma. Recent studies have disclosed two separate plasma kinetic pools consisting of mono- and diferric transferrin, and have demonstrated the effect of their relative abundance on tissue iron uptake. Allowance for the amount of each has made possible the calculation of iron-bearing transferrin uptake, which is independent of plasma iron concentration as long as receptors are saturated. This refinement permits the measurement of functional erythron transferrin receptors, and thereby the relative number of immature erythroid cells. [less ▲]

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See detailFerrokinetic study of splenic erythropoiesis: relationships among clinical diagnosis, myelofibrosis, splenomegaly, and extramedullary erythropoiesis.
Beguin, Yves ULg; Fillet, Georges ULg; Bury, J. et al

in American Journal of Hematology (1989), 32(2), 123-8

Splenic erythropoiesis was demonstrated by surface counting of 59Fe in 129 of 1,350 ferrokinetic studies performed over a 15 year period. These 129 studies were carried out in 108 patients, including 40 ... [more ▼]

Splenic erythropoiesis was demonstrated by surface counting of 59Fe in 129 of 1,350 ferrokinetic studies performed over a 15 year period. These 129 studies were carried out in 108 patients, including 40 with chronic myelogenous leukemia (CML), 24 with agnogenic myeloid metaplasia (AMM), 18 with polycythemia vera (PV), six with a myelodysplastic syndrome, five with acute leukemia, three with prostate or breast carcinoma, two each with aplastic anemia or Hodgkin's disease, and one each with idiopathic thrombocythemia, multiple myeloma, chronic renal failure, or treated hypopituitarism. Splenomegaly was present in 83% of the studies and hepatomegaly in 72%. Grade II-III myelofibrosis was demonstrated in 62% of the cases. Hepatic erythropoiesis was present in 77% of the studies (only 38% in PV), and marrow erythropoiesis was undetectable in 33%. Total erythropoiesis was about twice normal (range 0.2 to 8 times normal) but was ineffective to varying degrees in 86% of the studies. Relationships between organomegaly, myelofibrosis, and extramedullary erythropoiesis, as well as differences among clinical disorders, are discussed. Differences observed between CML in chronic or blastic phase suggested that the erythroid cell line was involved in the proliferative process. It is concluded that splenic erythropoiesis 1) is encountered in a variety of clinical conditions; 2) is not necessarily associated with splenomegaly or myelofibrosis, even in the myeloproliferative disorders; 3) is part of a predominantly extramedullary (in the liver as well as in the spleen), expanded, and largely inefficient total erythropoiesis; and 4) can be evaluated in a semiquantitative manner by surface counting. [less ▲]

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See detailFerrorosemaryite, NaFe2+Fe3+Al(PO4)3, a new phosphate mineral from the Rubindi pegmatite, Rwanda.
Hatert, Frédéric ULg; Lefèvre, Pierre; Fransolet, André-Mathieu ULg et al

in European Journal of Mineralogy (2005), 17

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See detailFers et bois dans les combles médiévaux et modernes du sud de la Belgique. Contribution à l'histoire de la construction en Europe occidentale
Maggi, Christophe ULg

Doctoral thesis (2014)

After four years of doctoral research on the topic of iron in the roof framing, a detailed typologic timeline could be established. It covers the period between the thirteenth and eighteenth century. The ... [more ▼]

After four years of doctoral research on the topic of iron in the roof framing, a detailed typologic timeline could be established. It covers the period between the thirteenth and eighteenth century. The development of such an inventory was possible by the development of an interdisciplinary methodology combining dendrochronology, archaeometallurgy and techniques of building archeology. Reflections and comparisons crossed with nearly 750 armatures from the investigation of 68 roof or attic parts, mainly located in Wallonia, helped to inventory 89 differents frames iron models. [less ▲]

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See detailLa fertilisation des plantes de grandes cultures
Falisse, André; Bodson, Bernard ULg; Cors, François et al

in Fertilisation des plantes (1985, December)

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See detailFertilisation des plantes de grandes cultures.
Falisse, André ULg; Bodson, Bernard ULg; Cors, François et al

in Annales de Gembloux (1986), 92(3), 233-245

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See detailFertilité des sols, agriculture durable de conservation pour préserver la planète
Mergeai, Guy ULg; Aloni Komanda, Jules

in La voix du Congo profond, le magazine d'un congo rural en marche (2010)

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See detailLa fertilité et la biodiversité dans les sols
Genot, Valérie ULg; Colinet, Gilles ULg; Bock, Laurent ULg

in Delbeuck, C. (Ed.) Rapport analytique sur l'état de l'environnement wallon 2006-2007 (2007)

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See detailFertilite male chez les bovins et taux sanguin d'hormone luteinisante et de testosterone.
Renaville, Robert ULg; Delecour, Beatrice; Ettaib, A. et al

in Bulletin des Recherches Agronomiques de Gembloux (1980), 15(4), 333-348

We determined blood plasma testosterone (T) values in bulls from the Friesian (N) and the Belgian White Blue (BBB) breeds, between 1 and 12 months of age. The BBB breed is divided into 2 sub-breeds: one ... [more ▼]

We determined blood plasma testosterone (T) values in bulls from the Friesian (N) and the Belgian White Blue (BBB) breeds, between 1 and 12 months of age. The BBB breed is divided into 2 sub-breeds: one is highly specialized for meat production (BBB-V); the other has mixed zootechnic characteristics (BBB-M). The results obtained show that T values in PN are significantly higher than in BBB-V, for at least, the first 5 months of life. In a second experiment, we followed T profiles for 12 or 24 hours in PN, BBB-M and BBB-V bulls. Every 20 minutes, blood was withdrawn from the jugular vein through a catheter, in order to minimized stress. Data observes are as follows: (1) Luteinizing hormone (LH) plasma levels are comparable in all animals at 130 and 180 days. From then on, average LH values slightly decreased in BBB-V whilst they increase in PN. As early as 130 days, LH secretion shows successive pulses in BBB-V, a similar pulsatile profile appearing later on in PN. (2) Average T values are significantly higher in PN and BBB-M than in BBB-V. T profiles are flat but of increasing average level up to 140 days in PN and 170 days in BBB-V. Thereafter, pulses develop. (3) 24 hour profiles show no influence of daylight upon LH or T parameters. (4) T peaks follow LH peaks by a delay of 60 to 100 minutes. (5) Frequency and amplitude of LH and T peaks differ, on the same day, among two monozygous twins. A third experiment showed that LH and T profiles were similar in two adult BBB-V bulls with significantly different fertility grades. We hypothesize that the delay of sexual maturing frequently observed in sub-breeds highly selected for meat production (BBB-V, for exemple) is related to the delay shown by animals of these breeds to develop T pulsatile profiles with peaks of adequate frequency and amplitude. [less ▲]

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See detailFertility and pregnancy after adjuvant therapy
JERUSALEM, Guy ULg

Conference (2014, September 19)

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See detailFertility in first-generation hybrids of roach, Rutilus rutilus (L.), and silver bream, Blicca bjoerkna (L.)
Nzau Matondo, Billy; Nlemvo, A. B.; Ovidio, Michaël ULg et al

in Journal of Applied Ichthyology (2008), 24(1), 63-67

Fertility in first-generation hybrids of roach, Rutilus rutilus, and silver bream, Blicca bjoerkna, was investigated. Sperm and egg production of hybrids at first sexual maturity were examined. Eggs from ... [more ▼]

Fertility in first-generation hybrids of roach, Rutilus rutilus, and silver bream, Blicca bjoerkna, was investigated. Sperm and egg production of hybrids at first sexual maturity were examined. Eggs from female hybrids were artificially fertilized with the sperm of a corresponding hybrid male; a hybrid male from the reciprocal crossbreeding; a parental species male R. rutilus; and a parental species male B. bjoerkna. The results revealed that gametogenesis was normal in female hybrids. However, in male hybrids, a low efficiency of gametogenesis was observed. The semen of male hybrids was extremely dilute, with spermatozoa concentration lower than that in parental species. Nevertheless, these F1 hybrids (males and females) from reciprocal crossbreeding were fertile. F2 and backcross generations were produced, but F2 crosses from the female hybrid and corresponding hybrid male displayed a drastically slower hatching rate. Also higher proportions of deformed embryos were hatched than in other post-F1-generation crosses. [less ▲]

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See detailFertility Preferences and Level of Family Planning in Rwanda : Case of Huye District
Niwemahoro, Celine; Musabanganji, Edouard ULg; Banamwana, Leonidas

in Journal of Emerging Trends in Economics and Management Sciences (JETEMS) (2011), 2(3), 168-174

The eradication of poverty and hunger is the first of the Millennium Development Goals (MDGs) established by the United ations. One of the Rwanda’s commitments is the fulfillment of this goal as indicated ... [more ▼]

The eradication of poverty and hunger is the first of the Millennium Development Goals (MDGs) established by the United ations. One of the Rwanda’s commitments is the fulfillment of this goal as indicated in its own long term Vision 2020 aimed at enabling Rwandans to emerge from under-development and poverty status by achieving economic growth objectives in combination with social indicators objectives. As it has been researched that the major cause of poverty in developing countries is the high rate of their population growth, this paper is aimed at assessing the fertility preferences and the level of family planning in Rwanda as a tool to poverty eradication. The paper also presents some challenges and some other pathways to improve the socioeconomic welfare of Rwandan population. In this paper descriptive methods have been used to present and analyze data and a Pearson Chi square test has been used to study the association between variables. The results shows that the knowledge of contraception is universal (99%) but the use of contraception methods for family planning is still very low (37%). On the average fertility preferences are 3.2 children which are good if realized. The general conclusion that emerges from the study is that in order to reduce poverty, family planning is a must but lot more are to be done. Among other things, a focus on increasing rural income and agriculture output. [less ▲]

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See detailFertility, human capital accumulation, and the pension system
Pestieau, Pierre ULg

in Journal of Public Economics (2011), 95

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