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Publications ORBi OA
Photoionization Mass Spectrometry of Kinetic energy-selected ions. An Ion Retarding Potential Difference method applied to NO+ and O+ from N2O.Locht, Robert ; ; et alin Chemical Physics (1991), 151 A new method is described to obtain photoionization efficiency curves of kinetic energy-selected fragment ions. The method is tested and discussed in the case of the dissociative photoionization yields of ... [more ▼] A new method is described to obtain photoionization efficiency curves of kinetic energy-selected fragment ions. The method is tested and discussed in the case of the dissociative photoionization yields of NO+ and O+ from N2O. The attention is focussed on the dissociative autoionization processes in the threshold region, in the Franck-Condon region of the N2O(A2Sigma+) state and in the Franck-Condon gap between the A2Sigma+ and B2Pi states. [less ▲] Detailed reference viewed: 14 (1 ULg) Vibrational Autoionization in NH3 and its Isotopomers in the 10-12 eV photon energy range.Locht, Robert ; Leyh, Bernard ; et alin McCarthy, I. E.; MacGillivray, W. R.; Weigold, E. (Eds.) et al 17th International Conference on the Physics of Electronic and Atomic Collisions. Book of Abstracts. (1991) The observation and detailed analysis of the vibrational autoionization in NH3 and its three isotopomers is reported. Detailed reference viewed: 28 (4 ULg) Photoionization of NH3 and its Isotopomers between 10 and 12 eV.Locht, Robert ; Leyh, Bernard ; et alin Kistemaker, P. G.; Nibbering, N. M. (Eds.) Advances in Mass Spectrometry: Proceedings of the 12th IMSC, Amsterdam (International Mass Spectrometry Conference 26-30 August 1991): Book of Abstracts. (1991) The photoionization of NH3 and its isotopomers is measured between 10-12 eV photon energy by using synchrotron radiation. The abundant autoionization structure observed in the ionization efficiency curves ... [more ▼] The photoionization of NH3 and its isotopomers is measured between 10-12 eV photon energy by using synchrotron radiation. The abundant autoionization structure observed in the ionization efficiency curves is analyzed. [less ▲] Detailed reference viewed: 24 (3 ULg) Polarization correction to the electrostatic potential at the CNDO and theab initio level. Influence of the basis set expansionDehareng, Dominique ; Dive, Georges ; Ghuysen, Jean-Marie ![]() in Theoretica Chimica Acta (1991), 79(2), 141-152 The influence of the basis set on the electrostatic potential corrected for polarization has been studied for H2S, CH3SH and COHCH2SH. The position and deepness of the minima and the height of the barrier ... [more ▼] The influence of the basis set on the electrostatic potential corrected for polarization has been studied for H2S, CH3SH and COHCH2SH. The position and deepness of the minima and the height of the barrier between symmetric minima is discussed at both the deorthogonalized CNDO/2 and ab initio levels within STO-3G, 3-21G, 4-31G, 6-31G and 6-311G basis sets. The calculation of the electrostatic potential and corrected one using CNDO deorthogonalized coefficients including 3d orbitals has been applied at the first time on sulfur-containing molecules. The influence of polarization and diffuse functions has also been analysed and the incidence of the polarization correction on the relative proton affinity in NH2(CH2)3NHCH3 and in the adenine molecule has been investigated at the CNDO and ab initio levels. At both levels, the relative proton affinity of several basic sites in the same molecule can be qualitatively expressed without inclusion of the polarization correction except in the case of substituted amines. [less ▲] Detailed reference viewed: 14 (1 ULg) Blunted erythropoietin production and decreased erythropoiesis in early pregnancy.Beguin, Yves ; ; et alin Blood (1991), 78(1), 89-93 After decreasing in the first trimester of pregnancy, the total red blood cell mass increases in the second and third trimesters to peak at term at about 120% to 125% of nonpregnant values, but how this ... [more ▼] After decreasing in the first trimester of pregnancy, the total red blood cell mass increases in the second and third trimesters to peak at term at about 120% to 125% of nonpregnant values, but how this is brought about by changes in the rate of erythropoiesis is not known. We evaluated erythropoiesis by measuring serum transferrin receptor (TfR) levels in 406 women during normal pregnancy (N = 317), at delivery (N = 63), or in the early postpartum (N = 27). Despite the presence of the placenta and the frequent occurrence of iron deficiency, TfR levels remained low in the first two trimesters and increased in the third trimester and at delivery. To explain why erythropoiesic activity was relatively low in early pregnancy, we also measured serum immunoreactive erythropoietin (Epo) in relation to the degree of anemia. There was a very strong correlation between serum TfR and Epo levels in the entire group (r = .59, P less than .0001) as well as in each period of pregnancy. Epo levels remained low for the degree of anemia and did not correlate with hematocrit in the first two trimesters, but recovered afterwards. In the early postpartum, Epo production and erythropoiesis were normal. We conclude that: (1) erythropoiesis is decreased in the first part of pregnancy but increases afterwards; and (2) blunted Epo production in early pregnancy could be responsible for that observation. [less ▲] Detailed reference viewed: 11 (0 ULg) Circulating erythropoietin levels after bone marrow transplantation: inappropriate response to anemia in allogeneic transplants.Beguin, Yves ; ; Oris, Renée et alin Blood (1991), 77(4), 868-73 We studied 24 recipients of autologous bone marrow transplantation (ABMT) or allogeneic BMT (BMT) to determine whether impaired erythropoietin (Epo) response to anemia could delay full erythropoietic ... [more ▼] We studied 24 recipients of autologous bone marrow transplantation (ABMT) or allogeneic BMT (BMT) to determine whether impaired erythropoietin (Epo) response to anemia could delay full erythropoietic recovery. Observed Epo levels were compared with predicted levels based on the relationship between Epo and hematocrit in 125 control subjects. Circulating Epo levels were normal during conditioning and the early posttransplant period. Between days 21 and 180, Epo levels remained normal in ABMT patients but were inappropriately low for the degree of anemia in BMT patients. Median time to full erythropoietic engraftment was longer in BMT than in ABMT recipients. Circulating Epo returned to appropriate levels after day 180, except in patients with active cytomegalovirus infection. We conclude that impaired Epo response to anemia can contribute to delayed erythropoietic recovery after allogenic BMT. Renal toxicity of ciclosporin, interaction between host and donor marrow, and cytomegalovirus infection might play a role. This study could support the use of recombinant human Epo to accelerate erythropoietic engraftment after BMT. [less ▲] Detailed reference viewed: 14 (2 ULg) Etrangetés dans le Carnaval de Wilson HarrisPagnoulle, Christine ![]() in Palimpsestes (1991), 6 The article offers an exploration of the disconcerting strangeness at work in Wilson Harris' novels and the strategies called for when translating them, on the basis of a couple of pages drawn from the ... [more ▼] The article offers an exploration of the disconcerting strangeness at work in Wilson Harris' novels and the strategies called for when translating them, on the basis of a couple of pages drawn from the novel aptly entitled Carnival. [less ▲] Detailed reference viewed: 24 (6 ULg) Influence of Electronic Excitation in the Charge Reversal of halogenated Cations.Leyh, Bernard ; in International Journal of Mass Spectrometry and Ion Processes (1991), 107 Charge reversal of high kinetic energy (8keV) cations during collisions with atomic target gases (G=Xe, Kr, Ne) has been studied for CCln+ (n=1 or 2) ions resulting from dissociative electroionization of ... [more ▼] Charge reversal of high kinetic energy (8keV) cations during collisions with atomic target gases (G=Xe, Kr, Ne) has been studied for CCln+ (n=1 or 2) ions resulting from dissociative electroionization of CCl4. The influence of electronic excitation of the incident cation CCln+ and of the nature of the target gas G on the anion yield have been examined. In our experiments, the two-collision process CCln+->CCln+G+->(CCln-)+2G+ is predominant. By comparing the anion and cation yields as a function of the kinetic energy of the ionizing electrons, we found evidence, with some target gases, of the existence of long-lived excited states of CCl+ and CCl2+, which lead to an increase in the anion yield in comparison with charge reversal of the correponding ground state ions. For CCl+, we deduce an excitation energy of 4+/-1 eV with a lifetime longer than 6.2 µs. These results are compatible with the a3Pi long-lived state of CCl+ previously detected by optical spectroscopy and by charge-stripping experiments. Our experimental data on charge reversal and metastable dissociation of CCl2+ reveal the existence of a long-lived state (lifetime>8.2 µs) of CCl2+ lying at 4.3+/-1 eV above the ground state.Semi-empirical MNDO calculations show that the energy of the first quartet state, a4A2, is compatible with the observed excitation energy. The spin-orbit coupling-induced transition from the a4A2 state to the B2A2 state is suggested to play an important role in the metestable dissociation CCl2+*->(CCl+)+Cl. The origin of the increase in the anion yield when long-lived excited states of CCl+ and CCl2+ are charge-reversed is discussed. Step a is suggested to be responsible for this yield enhancement which is observed when an appropriate target gas makes this step quasi-resonant. [less ▲] Detailed reference viewed: 12 (0 ULg) Pollution of P Cygni line profiles by Fe IV and Fe V photospheric absorption in the ultraviolet spectrum of O-type stars; Surdej, Jean ; in Astronomy and Astrophysics (1991), 247 It is reported that the main pollution in the spectral ranges 1270-1500 and 1500-1860 A is caused by photospheric absorption lines of FeV and FeIV, respectively. Making use of the first order moment W1 of ... [more ▼] It is reported that the main pollution in the spectral ranges 1270-1500 and 1500-1860 A is caused by photospheric absorption lines of FeV and FeIV, respectively. Making use of the first order moment W1 of a P Cygni line profile, it is shown that the effect of this photospheric pollution may lead to systematic errors, exceeding typically 50 percent in the determination of mass loss rates. It is also emphasized that the importance to correct the observed P Cygni line profiles for this pollution when studying the dependence of the physical parameters, terminal velocity, etc. of the stellar winds upon the various classes and types of O stars. [less ▲] Detailed reference viewed: 17 (3 ULg) L'organisation d'une journée d'un enfant de 4 à 6 ans: Enquête dans la région liégeoiseCrahay, Marcel ; ; Hindryckx, Geneviève et alin Enfance (1991), 45(1-2), 127-152 Detailed reference viewed: 74 (15 ULg) How do preschool teacher's requests influence children's behaviors ?Crahay, Marcel ; in Teaching & Teacher Education (1991), 7(3), 221-239 Detailed reference viewed: 14 (0 ULg) Erythropoïétine : utilisaiton diagnostique et thérapeutiqueBeguin, Yves ; Fillet, Georges ![]() in Revue de l’Association Belge des Technologues de Laboratoire = Tijdschrift van de Belgische Vereniging van Laboratoriumtechnologen (1991), 18(3), 161-168 L'érythropoïétine est une hormone produite par le rein en réponse à une hypoxie rénale et qui stimule l'activité érythropoïétique de la moelle osseuse. Le dosage de l'érythropoïétine sérique, toujours ... [more ▼] L'érythropoïétine est une hormone produite par le rein en réponse à une hypoxie rénale et qui stimule l'activité érythropoïétique de la moelle osseuse. Le dosage de l'érythropoïétine sérique, toujours interprété en fonction de l'hématocrite circulant, est utile dans le diagnostic différentiel des polyglobulies et dans certains cas particuliers d'anémie. L'utilisation thérapeutique de l'érythropoïétine recombinante a permis de corriger l'anémie de l'insuffisance rénale chronique et est actuellement étudiée dans d'autres indications telles que les anémies inflammatoires. [less ▲] Detailed reference viewed: 34 (2 ULg) Allergic cross-reaction of teicoplanin and vancomycin; ; et al in Journal of Antimicrobial Chemotherapy (1991), 28 Detailed reference viewed: 18 (0 ULg) L'examen cytogénétique en onco-hématologie : son importance dans la stratégie thérapeutique; ; et al in Médecine et Hygiène (1991), 49 The findings that chromosomal aberrations are specifically associated with a considerable number of tumors and particularly leukemia, have lead the cytogenetic studies to be considered particularly ... [more ▼] The findings that chromosomal aberrations are specifically associated with a considerable number of tumors and particularly leukemia, have lead the cytogenetic studies to be considered particularly contributive in haematological practices. Since the discovery of th Philadelphia chromosome linked with the chronic myeloid leukemia, technological improvements have allowed detection of others chromosomes specifically associated with some types or subtypes of leukemia, lymphomas and solid tumors. Today, cytogenetics is considered as a useful tool not only for diagnostic but also for prognosis and therapeutic. During the follow-up, it may assess not only complete remission, success of bone marrow transplantation but also relapse. Bone marrow cytogenetic studies are being now essential at diagnosis and during follow-up of patients with hematological proliferative tumors. Well done, cytogenetics studies may be of importance for the therapeutic decision. [less ▲] Detailed reference viewed: 218 (0 ULg) Thrombocytopénie allergique à la nitrofurantoïneSautois, Brieuc ; ; et alin Revue Médicale de Liège (1991), 46 Nous rapportons le dixième cas de thrombocytopénie à la nitrofurantoïne. Trois épisodes successifs sont décrits chez la même patiente, s'accompagnant de frissons et d'une thrombocytopénie extrême. La ... [more ▼] Nous rapportons le dixième cas de thrombocytopénie à la nitrofurantoïne. Trois épisodes successifs sont décrits chez la même patiente, s'accompagnant de frissons et d'une thrombocytopénie extrême. La récupération hématologique est rapide à l'arrêt du médicament (retour à 150 000 plaquettes après 3 à 4 jours), en rapport avec la demi-vie plasmatique brève de la nitrofurantoïne. [less ▲] Detailed reference viewed: 70 (0 ULg) Perspectives diagnostiques et thérapeutiques de l'érythropoïétineBeguin, Yves ; Sautois, Brieuc ; Fillet, Georges ![]() in Médecine et Hygiène (1991), 49 L'érythropoïétine est une hormone produite par le rein en réponse à une hypoxie rénale et qui stimule l'activité érythropoïétine de la moelle osseuse. Le dosage de l'érythropoïétine sérique, toujours ... [more ▼] L'érythropoïétine est une hormone produite par le rein en réponse à une hypoxie rénale et qui stimule l'activité érythropoïétine de la moelle osseuse. Le dosage de l'érythropoïétine sérique, toujours interpété en fonction de l'hématocrite circulante, est utilise dans le diagnostic différentiel des polyglobulies et dans certains cas particuliers d'anémie. L'utilisation thérapeutique de l'érythropoïétine recombinée a permis de corriger l'anémie de l'insuffisance rénale chronique et est actuellement étudiée dans d'autres indications. [less ▲] Detailed reference viewed: 46 (1 ULg) Modèles mathématiques en hydrogéologie et paramétrisationDassargues, Alain ![]() in Annales de la Société Géologique de Belgique (1991), 113(2), 217-229 Detailed reference viewed: 62 (20 ULg) A Spectroscopic Study of UM673 A &B: on the size of Lyman- alpha Clouds; Surdej, Jean ; et alin Quasar Absorption Lines, Proceedings of the ESO Mini-Workshop (1991) Not Available Detailed reference viewed: 15 (1 ULg) L'inertie dans la maison individuelle : un gain de consommation énergétique ? Simulation et étude de casNicolas, Jacques ; Andre, Philippe ; et alin Revue générale de thermique (1991), 30(352), 240-249 L'inertie thermique dans le bâtiment est l'une des composantes les plus étudiées en architecture bioclimatique. Le principal intérêt d'une grande capacité thermique est d'assurer le confort, surtout ... [more ▼] L'inertie thermique dans le bâtiment est l'une des composantes les plus étudiées en architecture bioclimatique. Le principal intérêt d'une grande capacité thermique est d'assurer le confort, surtout durant l'été, en déphasant les apports extérieurs et en atténuant les fluctuations de la température extérieure. L'inertie a beaucoup été étudiée dans des cellules-tests. La démarche décrite dans cet article se base sur une modélisation par le logiciel Suncode de différentes variantes d'une maison unifamiliale, représentative du parc de logement belge. Pour une maison purement passive, il s'avère que la consommation énergétique annuelle est beaucoup moins sensible à l'inertie qu'à l'isolation de la maison. Une saturation de consommation est même atteinte pour de grandes inerties. Pour assurer un déphasage supérieur à une journée, il conviendrait de favoriser un système actif de captation de l'énergie solaire qui serait directement injectée dans le milieu des parois épaisses de la maison. [less ▲] Detailed reference viewed: 52 (3 ULg) Métoda Marginilor RigidizateRigo, Philippe ; in Studii şi Cercetări de Mecanică Aplicată (1991) Detailed reference viewed: 25 (0 ULg) |
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