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See detailCyclic RR Telescopii
Heck, Andre; Manfroid, Jean ULiege

Article for general public (1984)

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See detailCyclic scheduling in 3-machine robotic flow shops
Crama, Yves ULiege; Van de Klundert, Joris

in Journal of Scheduling (1999), 2

We consider a robotic flow shop model in which a single robot is responsible for the transportation of parts between machines. For reasons of simplicity, when the shop is to produce a large number of ... [more ▼]

We consider a robotic flow shop model in which a single robot is responsible for the transportation of parts between machines. For reasons of simplicity, when the shop is to produce a large number of identical parts, the robot usually performs repeatedly a fixed sequence of activities. This sequence of activities is called a 1-unit cycle if each execution of the sequence results in the production of exactly one part. It has been conjectured that 1-unit cycles yield optimal production rates for 3-machine robotic flow shops. We establish the validity of this conjecture. [less ▲]

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See detailCyclic scheduling in robotic flowshops
Crama, Yves ULiege; Kats, Vladimir; Van de Klundert, Joris et al

in Annals of Operations Research (2000), 96

Fully automated production cells consisting of flexible machines and a material handling robot have become commonplace in contemporary manufacturing systems. Much research on scheduling problems arising ... [more ▼]

Fully automated production cells consisting of flexible machines and a material handling robot have become commonplace in contemporary manufacturing systems. Much research on scheduling problems arising in such cells, in particular, in flowshop-like production cells has been reported recently. Although there are many differences between the models, they all explicitly incorporate the interaction between the materials handling and the classical job processing decisions, since this interaction determines the efficiency of the cell. This paper surveys cyclic scheduling problems in robotic flowshops, models for such problems, and the complexity of solving these problems, thereby bringing together several streams of research that have by and large ignored one another, and describing and establishing links with other scheduling problems and combinatorial topics. [less ▲]

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See detailCyclic scheduling of identical parts in a robotic cell
Crama, Yves ULiege; Van de Klundert, Joris

in Operations Research (1997), 45

We consider a robotic flowshop in which one type of product is to be repeatedly produced and where transportation of the parts between the machines is performed by the robot. The identical parts cyclic ... [more ▼]

We consider a robotic flowshop in which one type of product is to be repeatedly produced and where transportation of the parts between the machines is performed by the robot. The identical parts cyclic scheduling problem is then to find a shortest cyclic schedule for the robot, i.e., a sequence of robot moves that can be repeated infinitely many times and has minimum cycle time. This problem has been solved by Sethi et al. (1992) when m <= 3. In this paper, we considerably generalize their results by proving that the identical parts cyclic scheduling problem can be solved in time polynomial in m, where m denotes the number of machines in the shop. In particular, we present a dynamic programming approach that allows to solve the problem in O(m^3) time. Our analysis heavily relies on the concept of pyramidal permutation, a concept previously investigated in connection with the traveling salesman problem. [less ▲]

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See detailCyclic variations in incubation conditions induce adaptive responses to later heat exposure in chickens: a review
Loyau, T.; Bedrani, L.; Berri, C. et al

in Animal (2015), 9

Selection programs have enabled broiler chickens to gain muscle mass without similar enlargement of the cardiovascular and respiratory systems that are essential for thermoregulatory efficiency. Meat-type ... [more ▼]

Selection programs have enabled broiler chickens to gain muscle mass without similar enlargement of the cardiovascular and respiratory systems that are essential for thermoregulatory efficiency. Meat-type chickens cope with high ambient temperature by reducing feed intake and growth during chronic and moderate heat exposure. In case of acute heat exposure, a dramatic increase in morbidity and mortality can occur. In order to alleviate heat stress in the long term, research has recently focused on early thermal manipulation. Aimed at stimulation of long-term thermotolerance, the thermal manipulation of embryos is a method based on fine tuning of incubation conditions, taking into account the level and duration of increases in temperature and relative humidity during a critical period of embryogenesis. The consequences of thermal manipulation on the performance and meat quality of broiler chickens have been explored to ensure the potential application of this strategy. The physiological basis of the method is the induction of epigenetic and metabolic mechanisms that control body temperature in the long term. Early thermal manipulation can enhance poultry resistance to environmental changes without much effect on growth performance. This review presents the main strategies of early heat exposure and the physiological concepts on which these methods were based. The cellular mechanisms potentially underlying the adaptive response are discussed as well as the potential interest of thermal manipulation of embryos for poultry production. © The Animal Consortium 2014. [less ▲]

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See detailCyclical Cushing's disease : a case report.
Velkeniers, B.; Beckers, Albert ULiege; Stevenaert, Achille ULiege et al

in Pathology - Research & Practice (1991), 187(5), 603-607

A 41-year-old man with clinical Cushing's syndrome and intermittent central ACTH hypersecretion for a period of 9 1/2 years follow-up is described. Episodes of biochemical and clinical remission ... [more ▼]

A 41-year-old man with clinical Cushing's syndrome and intermittent central ACTH hypersecretion for a period of 9 1/2 years follow-up is described. Episodes of biochemical and clinical remission alternated with periods of florid Cushing's disease, characterized by circadian hyperpulsatile ACTH and cortisol secretion. Responses to metyrapone and inhibition of ACTH and cortisol hypersecretion after high dose dexamethasone during active phases of the disease favored a central origin of ACTH hypersecretion, confirmed by simultaneous bilateral venous sampling of the sinus petrosus inferior. Prolonged clinical remission followed near total anterior hypophysectomy. However, on anatomopathological examination of the pituitary neither corticotroph cell hyperplasia nor a microadenoma could be documented. The possibility of a functional ACTH hypersecretion is discussed. [less ▲]

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See detailCyclical Cushing's disease : a case report.
Velkeniers, B.; Beckers, Albert ULiege; Stevenaert, Achille ULiege et al

in Société Belge de Médecine Interne (1990)

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See detailCyclical Cushing's disease and its successful control under sodium valproate.
Beckers, Albert ULiege; Stevenaert, Achille ULiege; Pirens, G. et al

in Journal of Endocrinological Investigation (1990), 13(11), 923-9

Several subgroups of Cushing's disease were recently described (anterior or intermediate lobe origin, hyper-or hypo-pulsatility of cortisol, presence or absence of response after GRH or TRH, cyclical ... [more ▼]

Several subgroups of Cushing's disease were recently described (anterior or intermediate lobe origin, hyper-or hypo-pulsatility of cortisol, presence or absence of response after GRH or TRH, cyclical Cushing's disease). We present here a detailed case report on a patient suffering from Cushing's disease whose endocrine functions were extensively investigated. Treatment with bromocriptine, as well as subsequent transsphenoidal surgery, were followed by rapid but transient reversal of symptoms. When clinical manifestations reoccurred, daily measurements of free urinary cortisol revealed a cyclic pattern of cortisol hyperexcretion. A study of ultradian rhythm revealed hyperpulsatility of cortisol secretion. More interestingly, a treatment with sodium valproate, a drug known to inhibit CRH production, was followed by a rapid and longstanding normalization of clinical and biological data for 2 years. Based on these data, and on information from the literature, the present case of Cushing's disease exhibits characteristics suggesting a possible hypothalamic origin. [less ▲]

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See detailCyclical Spectral and Photometric Variations of the Apparently Single Wolf-Rayet Star WR 134
Morel, Thierry ULiege; Marchenko, S. V.; Eenens, P. R. J. et al

in Astrophysics & Space Science (1998), 260

Evidence is presented for the existence of a 2.3 day periodicity in the line-profile changes of the apparently singleWolf-Rayet star WR 134. This cyclical variability may be induced either by the presence ... [more ▼]

Evidence is presented for the existence of a 2.3 day periodicity in the line-profile changes of the apparently singleWolf-Rayet star WR 134. This cyclical variability may be induced either by the presence of an orbiting collapsed companion, or by the rotational modulation of a largely inhomogeneous outflow. [less ▲]

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See detailA cyclical square-root model for the term structure of interest rates
Platania, Federico ULiege; Moreno, Manuel

in European Journal of Operational Research (2015)

This paper presents a cyclical square-root model for the term structure of interest rates assuming that the spot rate converges to a certain time-dependent long-term level. This model incorporates the ... [more ▼]

This paper presents a cyclical square-root model for the term structure of interest rates assuming that the spot rate converges to a certain time-dependent long-term level. This model incorporates the fact that the interest rate volatility depends on the interest rate level and specifies the mean reversion level and the interest rate volatility using harmonic oscillators. In this way, we incorporate a good deal of flexibility and provide a high analytical tractability. Under these assumptions, we compute closed-form expressions for the values of different fixed income and interest rate derivatives. Finally, we analyse the empirical performance of the cyclical model versus that proposed in Cox et al. (1985) and show that it outperforms this benchmark, providing a better fitting to market data. [less ▲]

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See detailCyclin D1-negative mantle cell lymphoma with cryptic t(12;14)(p13;q32) and cyclin D2 overexpression.
Herens, Christian ULiege; Lambert, Frédéric ULiege; Quintanilla-Martinez, Leticia et al

in Blood (2008), 111(3), 1745-6

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See detailCyclin dependant kinase inhibitor 1B (CDKN1B) gene mutations in familial isolated pituitary adenomas (FIPA) : Analysis in 84 families
Apetrii, P.; Tikhomirova, M.; Daly, Adrian ULiege et al

in 18th Meeting of the Belgian Endocrine and Metabolic societies : Bruxelles, 25 octobre 2008 (2008, October)

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See detailCyclin dependant kinase inhibitor 1B (CDKN1B) gene mutations in familial isolated pituitary adenomas (FIPA) : Analysis in 86 families
Tichomoriva, M.; Barlier, A.; Daly, Adrian ULiege et al

in 52 Symposium der Deutschen Gesellschaft für Endokrinologie (2009, March)

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See detailCyclin dependent kinase inhibitor (CDKN1B) gene variants in AIP mutation-negative familial isolated pituitary adenomas (FIPA) kindreds
Tichomirowa, M.; Lee, M.; Barlier, A. et al

in Endocrine-Related Cancer (2012), 19

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See detailCyclin dependent kinase inhibitor 1B (CDKN1B) gene mutations in FIPA
Tichomirowa, M. A.; Pellegata, N. S.; Barlier, A. et al

in European Neuroendocrine Association - Liège, 22-25 septembre 2010 (2010, September)

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See detailCyclin-dependent kinase-2 controls oligodendrocyte progenitor cell cycle progression and is downregulated in adult oligodendrocyte progenitors.
Belachew, Shibeshih ULiege; Aguirre, Adan A.; Wang, Hang et al

in Journal of Neuroscience (2002), 22(19), 8553-62

Proliferation of oligodendrocyte progenitor (OP) cells is a crucial process controlling myelination in the CNS. Previous studies demonstrated a correlation between OP proliferation rate and cyclin E ... [more ▼]

Proliferation of oligodendrocyte progenitor (OP) cells is a crucial process controlling myelination in the CNS. Previous studies demonstrated a correlation between OP proliferation rate and cyclin E/cyclin-dependent kinase-2 (cdk2) activity. To establish a causal link between cyclin E/cdk2 activity and OP proliferation, we selectively modulated cdk2 activity in vitro by transfection of cultured OP cells. Dominant-negative (Dn)-cdk2 overexpression inhibited mitogen-induced OP cell proliferation, whereas wild-type (wt)-cdk2 prevented cell cycle arrest caused by anti-mitotic signals. Dn-cdk2- or wt-cdk2-mediated regulation of G(1)/S transition, per se, did not influence initiation of OP differentiation. To study the function of cyclin E/cdk2 in OP cells during development in vivo, we analyzed cdk2 and cyclin E expression in cells acutely isolated from transgenic mice expressing the green fluorescent protein (GFP) under the control of the 2'-3'-cyclic nucleotide 3'-phosphodiesterase gene promoter. Both cyclin E/cdk2 protein levels and activity were decreased in GFP(+) oligodendrocyte lineage cells between postnatal days 4 and 30. Immunostaining of NG2(+)/GFP(+) OP cells in brain tissue sections showed a 90% decrease in overall cell proliferation and cdk2 expression between perinatal and adult cells. However, cdk2 expression within the proliferating (i.e., expressing the proliferating cell nuclear antigen) OP cell population was maintained throughout development. Our data indicate that: (1) cyclin E/cdk2 activity plays a pivotal function in OP cell cycle decisions occurring at G(1)/S checkpoint; (2) initiation of OP differentiation is independent of cyclinE/cdk2 checkpoint, and (3) intrinsic differences in cyclin E/cdk2 expression and activity may underlie the slowly proliferative state that characterizes so-called "quiescent" adult OP cells in vivo. [less ▲]

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See detailCyclin-dependent protein kinase inhibitors in breast cancer treatment
FRERES, Pierre ULiege; LOUSBERG, Laurence ULiege; JERUSALEM, Guy ULiege

in Belgian Journal of Medical Oncology [=BJMO] (2016), 10(4), 132-138

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See detailCycling or not cycling: cell cycle regulatory molecules and adult neurogenesis.
Beukelaers, Pierre ULiege; Vandenbosch, Renaud ULiege; Caron, Nicolas ULiege et al

in Cellular and Molecular Life Sciences : CMLS (2012), 69(9), 1493-1503

The adult brain most probably reaches its highest degree of plasticity with the lifelong generation and integration of new neurons in the hippocampus and olfactory system. Neural precursor cells (NPCs ... [more ▼]

The adult brain most probably reaches its highest degree of plasticity with the lifelong generation and integration of new neurons in the hippocampus and olfactory system. Neural precursor cells (NPCs) residing both in the subgranular zone of the dentate gyrus and in the subventricular zone of the lateral ventricles continuously generate neurons that populate the dentate gyrus and the olfactory bulb, respectively. The regulation of NPC proliferation in the adult brain has been widely investigated in the past few years. Yet, the intrinsic cell cycle machinery underlying NPC proliferation remains largely unexplored. In this review, we discuss the cell cycle components that are involved in the regulation of NPC proliferation in both neurogenic areas of the adult brain. [less ▲]

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See detailCyclo-oxygenase type 2-dependent prostaglandin E-2 secretion is involved in retrovirus-induced T-cell dysfunction in mice
Rahmouni, Souad ULiege; Aandahl, Einar Martin; Nayjib, Btissam ULiege et al

in Biochemical Journal (2004), 384(Pt 3), 469-476

MAIDS (murine AIDS) is caused by infection with the murine leukaemia retrovirus RadLV-Rs and is characterized by a severe immunodeficiency and T-cell anergy combined with a lymphoproliferative disease ... [more ▼]

MAIDS (murine AIDS) is caused by infection with the murine leukaemia retrovirus RadLV-Rs and is characterized by a severe immunodeficiency and T-cell anergy combined with a lymphoproliferative disease affecting both B- and T-cells. Hyperactivation of the cAMP-protein kinase A pathway is involved in the T-cell dysfunction of MAIDS and HIV by inhibiting T-cell activation through the T-cell receptor. In the present study, we show that MAIDS involves a strong and selective up-regulation of cyclo-oxygenase type 2 in the CD11b+ subpopulation of T- and B-cells of the lymph nodes, leading to increased levels of PGE2 (prostaglandin E2). PGE2 activates the cAMP pathway through G-protein-coupled receptors. Treatment with cyclo-oxygenase type 2 inhibitors reduces the level of PGE2 and thereby reverses the T-cell anergy, restores the T-cell immune function and ameliorates the lymphoproliferative disease. [less ▲]

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