304 research outputs found

    Facilitated engraftment of human hematopoietic cells in severe combined immunodeficient mice following a single injection of Cl²MDP liposomes

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    Transplantation of normal and malignant human hematopoietic cells into severe combined immunodeficient (SCID) mice allows for evaluation of long-term growth abilities of these cells and provides a preclinical model for therapeutic interventions. However, large numbers of cells are required for successful engraftment in preirradiated mice due to residual graft resistance, that may be mediated by cells from the mononuclear phagocytic system. Intravenous (i.v.) injection of liposomes containing dichloromethylene diphosphonate (Cl2MDP) may eliminate mouse macrophages in spleen and liver. In this study outgrowth of acute myeloid leukemia (AML) cells and umbilical cord blood (UCB) cells in SCID mice conditioned with a single i.v. injection of Cl2MDP liposomes in addition to sublethal total body irradiation (TBI) was compared to outgrowth of these cells in SCID mice that had received TBI alone. A two- to 10-fold increase in outgrowth of AML cells was observed in four cases of AML. Administration of 107 UCB cells reproducibly engrafted SCID mice that had been conditioned with Cl2MDP liposomes and TBI, whereas human cells were not detected in mice conditioned with TBI alone. As few as 2 x 104 purified CD34+ UCB cells engrafted in all mice treated with Cl2MDP liposomes. In SCID mice treated with macrophage depletion unexpected graft failures were not observed. Histological examination of the spleen showed that TBI and Cl2MDP liposomes i.v. resulted in a transient elimination of all macrophage subsets in the spleen, whereas TBI had a minor effect. Cl2MDP liposomes were easy to use and their application was not associated with appreciable side-effects. Cl2MDP liposome pretreatment in combination with TBI allows for reproducible outgrowth of high numbers of human hematopoietic cells in SCID mice

    Повернення в Ніжин (корпус документів з епістолярію І.Г. Спаського)

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    Підготовка до друку та переднє слово Наталії ДМИТРЕНКО (Ніжин), коментарі Сергія ЗОЗУЛІ (Київ–Ніжин): Уперше вводиться до наукового обігу корпус джерел з епістолярію українського та російського радянського історика-нумізмата, музейника І.Г. Спаського. Корпус джерел який містить кореспонденцію, отриману відомим науковцем від кореспондентів-ніжинців, і де, здебільшого, відображена “ніжинська тематика” – проблеми збереження культурної спадщини Ніжина, післявоєнного розвитку міста тощо.Подготовка к печати и предисловие Наталии ДМИТРЕНКО (Нежин), комментарии Сергея ЗОЗУЛИ (Киев–Нежин): Впервые вводится в научный оборот корпус источников из эпистолярия украинского и российского советского историка-нумизмата, музейщика И.Г. Спасского. Корпус источников содержит корреспонденцию, полученную известным ученым от корреспондентов-нежинцев, и в котором преимущественно отображена “нежинская тематика” – проблемы сохранения культурного наследия Нежина, послевоенного развития города и т.п.Preparation to the print and preface of Nataliya DMYTRENKO (Nizhyn), comments of Serhiy ZOZULYA (Kyiv–Nizhyn): The corps of sources from the epistolary legacy of the Ukrainian and Russian soviet historiannumismatist and museum worker I.G. Spas’kiy is entered to the scientific appeal in the first time. This corps of sources contains correspondence got the known scientist from Nizhynians and contains mostly “Nizhyn themes” – problems of protect of Nizhyn’s cultural legacy, post-war development of this town etc

    Changes in the Horticulture Sector in the Netherlands

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    The goal of this study is to analyse and to investigate the investment dynamics in Dutch glasshouse horticulture, and to reveal the factors underlying the changes in this sector. Insight into the effect of different factors on the investment behaviour in Dutch horticulture is socially relevant because this sector has to undergo structural changes. The Dutch glasshouse industry has to improve its environmental performance (reduce its energy use, pesticides, use and CO2 emissions). Improvement of the environmental performance can be achieved by investments in new technologies (e.g. energy saving technologies). Insights into factors that determine investment patterns are important in designing policies that aim at enhancing the environmental performance of horticulture. Also, insights into factors that affect investment patterns in the glasshouse industry are relevant for assessing future credit demand of the glasshouse industry by banks. Panel data from the Farm Accountancy Data Network (FADN) were used to describe the dynamics of the investments during 1975-1998. Inspection of investment patterns of firms demonstrates that investments are not spread over a number of years. Rather, investments are concentrated in some years, followed by some years without any significant investment activity. Another feature from inspection of data is that investment patterns differ between capital goods (e.g. machines, installations, buildings) and between sectors (vegetable, cut-flower, pot-plant). A factor analysis was used to explore the structure of the interrelationships among variables

    Symmetries of the Kac-Peterson Modular Matrices of Affine Algebras

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    The characters χμ\chi_\mu of nontwisted affine algebras at fixed level define in a natural way a representation RR of the modular group SL2(Z)SL_2(Z). The matrices in the image R(SL2(Z))R(SL_2(Z)) are called the Kac-Peterson modular matrices, and describe the modular behaviour of the characters. In this paper we consider all levels of (Ar1Ars)(1)(A_{r_1}\oplus\cdots\oplus A_{r_s})^{(1)}, and for each of these find all permutations of the highest weights which commute with the corresponding Kac-Peterson matrices. This problem is equivalent to the classification of automorphism invariants of conformal field theories, and its solution, especially considering its simplicity, is a major step toward the classification of all Wess-Zumino-Witten conformal field theories.Comment: 16 pp, plain te

    Increased rate of respiratory symptoms in children with Down syndrome:A 2-year web-based parent-reported prospective study

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    To compare the incidence of respiratory symptoms and short-term consequences between children with Down syndrome and children from the general population, we conducted a prospective parent-reported observational study. Children with Down syndrome (≤ 18 years) were included between March 2012 and June 2014. Caregivers received a baseline questionnaire with follow-up 1-2 years after inclusion. Caregivers received a weekly questionnaire about respiratory symptoms, fever, antibiotic prescriptions, doctor's visits, and consequences for school and work attendance. Children with Down syndrome were compared to a cohort of the general population ("Kind en Ziek" study) with similar weekly questionnaires. A total of 9,011 childweeks were reported for 116 participants with Down syndrome (75% response rate). The frequency of respiratory symptoms was higher in children with Down syndrome than in children from the general population (30% vs 15.2%). In addition, symptoms subsided later (around 8 vs 5 years of age). The seasonal influence was limited, both in children with Down syndrome and children from the general population. Consequences of respiratory disease were significant in children with Down syndrome compared to children from the general population, with a higher rate of doctor's visits (21.3% vs 11.8%), antibiotic prescriptions (47.8% vs 26.3%), and absenteeism from school (55.5% vs 25.4%) and work (parents, 9.4% vs 8.1%). Conclusion: Children with Down syndrome have a higher frequency of respiratory symptoms and symptoms last until a later age, confirming the impression of professionals and caregivers. Individualized treatment plans might prevent unfavorable consequences of chronic recurrent respiratory disease in children with Down syndrome. What is Known: • Children with Down syndrome have an altered immune system and are prone to a more severe course of respiratory tract infections. • The overall conception is that patients with Down syndrome suffer from respiratory tract infections more often. What is New: • Children with Down syndrome suffer from respiratory symptoms more frequently than children from the general population. • The respiratory symptoms in children with Down syndrome subside at a later age compared to children from the general population

    One Spin Trace Formalism for BK B_K

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    It has been known for some time that there are two methods to calculate BK B_K with staggered fermions: one is the two spin trace formalism and the other is the one spin trace formalism. Until now, the two spin trace formalism has been exclusively used for weak matrix element calculations with staggered fermions. Here, the one spin trace formalism to calculate BK B_K with staggered fermions is explained. It is shown that the one spin trace operators require additional chiral partner operators in order to keep the continuum chiral behavior. The renormalization of the one spin trace operators is described and compared with the two spin trace formalism.Comment: 47 pages, latex, 4 figures are available on reques

    Partial Flavor Symmetry Restoration for Chiral Staggered Fermions

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    We study the leading discretization errors for staggered fermions by first constructing the continuum effective Lagrangian including terms of O(a^2), and then constructing the corresponding effective chiral Lagrangian. The terms of O(a^2) in the continuum effective Lagrangian completely break the SU(4) flavor symmetry down to the discrete subgroup respected by the lattice theory. We find, however, that the O(a^2) terms in the potential of the chiral Lagrangian maintain an SO(4) subgroup of SU(4). It follows that the leading discretization errors in the pion masses are SO(4) symmetric, implying three degeneracies within the seven lattice irreducible representations. These predictions hold also for perturbatively improved versions of the action. These degeneracies are observed, to a surprising degree of accuracy, in existing data. We argue that the SO(4) symmetry does not extend to the masses and interactions of other hadrons (vector mesons, baryons, etc), nor to higher order in a^2. We show how it is possible that, for physical quark masses of O(a^2), the new SO(4) symmetry can be spontaneously broken, leading to a staggered analogue of the Aoki-phase of Wilson fermions. This does not, however, appear to happen for presently studied versions of the staggered action.Comment: 26 pages, 2 figures (using psfig). Version to appear in PRD (clarifications added to introduction and section 6; typos corrected; references updated

    Musical Women and Identity-Building in Early Independent Mexico (1821-1854)

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    This thesis investigates music in Mexico City, with an emphasis on women's relationship to Romanticism, education, consumption, domestic music-making and public performance. During the first decades after independence in 1821, Mexicans began the process of constructing an identity, which musically speaking meant an expansion of the secular musical world. Such construction involved the development of internal activity alongside a conditional receptivity to external influence in the form of the visits of Italian opera companies such as those of Manuel García and Max Maretzek, and travelling virtuosi such as pianist virtuoso Henri Herz, who brought new repertoire and performance practices to Mexican theatres and homes. As consumers and as musicians, women were at the centre of such developments. In Mexico, both European music and that of local musicians was disseminated by means of ladies’ journals and imported and locally-printed sheet music by foreign and Mexican composers, in order to supply a growing home market for amateurs. Abundant surviving repertoire for the home, the widespread availability of musical instruction as revealed through advertisements, and witness accounts of soirées and concerts in the theatre reveal a budding musical world that has hitherto been overlooked and which occurred during a period generally deemed of little importance in Mexican musical history. By investigating a key period in the social-cultural history of Mexican music, this thesis crafts a narrative of intersections between the musical life of Mexican women and the incipient construction of a musical-cultural identity
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