509 research outputs found

    Drell-Yan process at forward rapidity at the LHC

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    We analyze the Drell-Yan lepton pair production at forward rapidity at the Large Hadron Collider. Using the dipole framework for the computation of the cross section we find a significant suppression in comparison to the collinear factorization formula due to saturation effects in the dipole cross section. We develop a twist expansion in powers of Q_s^2/M^2 where Q_s is the saturation scale and M the invariant mass of the produced lepton pair. For the nominal LHC energy the leading twist description is sufficient down to masses of 6 GeV. Below that value the higher twist terms give a significant contribution.Comment: 13 pages, 7 figure

    Crosstalk between environmental signals and 3d genome organization in the regulation of gene expression

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    The thesis explores the connection between environmental stimuli and gene expression regulated by the spatial changes in genome organization. In Paper I, by applying state of the art Circular Chromosome Conformation Capture assay (4C) and Chromatin in situ Proximity (ChrISP) techniques, we show that transcriptionally active circadian genes meet in space with repressed lamina-associated domains (LADs), and that these interactions are under the control of the circadian clock. External time cues thus synchronised circadian transcriptional oscillations by repositioning clock-controlled genes from the transcriptionally permissive sub-compartment of nuclear interior to the transcriptionally repressive nuclear periphery. These processes relied on the rhythmic formation of complexes between CTCF and PARP1, two master regulators of the genome, to increase the amplitude of circadian gene expression. In Paper II we took an advantage of the novel, ultrasensitive Nodewalk technique to explore the stochastic nature of MYC interactions with its flanking enhancers. By pushing the Nodewalk limits of identification of chromatin interactions in the input material corresponding to less than 8 cells, we could show that MYC is likely screening for neighbouring interaction partners rather than vice versa. Moreover, we could show that MYC does not interact with enhancers, once its transcription had been initiated. These findings suggest that enhancer hubs simultaneously interacting with MYC are likely virtual consequences of high cell population analyses and that MYC interacts with its enhancers in a mutually exclusive manner. Paper III concentrates on the role of a CTCF binding site within the oncogenic super- enhancer (OSE) in the regulation of MYC gene gating in colon cancer cells. CRISPR induced mutations in the CTCF binding site within the OSE abrogated WNT-dependent nuclear export of MYC mRNA, providing genetic evidence to the claim of the OSE- mediated gating of active MYC alleles to the nuclear pore.This manuscript documents, moreover, that the communication between OSE and MYC, as well as their repositioning to the nuclear pore, involves PARP1 to indicate a more general role for the CTCF :PARP1 complex in gene regulation. In summary, this thesis has uncovered novel principles underlying the roles of stochastic chromatin interactions and mobility within the 3D nuclear space to regulate gene expression with a focus on circadian transcriptional regulation and the recently discovered gene gating phenomenon in humans. These findings contribute to our understanding of principles in which the nuclear architecture and genome organisation synergize to induce or maintain the properties of the cell. By extrapolation, such findings might form a platform for identifying new therapeutic strategies to battle cancer, for example

    Intestinal colic in newborn babies: incidence and methods of proceeding applied by parents

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    Introduction: Intestinal colic is one of the more frequent complaints that a general practitioner and paediatrician deal with in their work. 10-40% of babies formula fed and 10-20% breast fed are stricken by this complaint. A colic attack appears suddenly and very quickly causes energetic, squeaky cry or even scream. Colic attacks last for a few minutes and appear every 2-3 hours usually in the evenings. Specialist literature provides numerous definitions of intestinal colic. The concept was introduced for the first time to paediatric textbooks over 250 years ago. One of the most accurate definitions describe colic as recurring attacks of intensive cry and anxiety lasting for more than 3 hours a day, 3 days a week within 3 weeks. Care of a baby suffering from an intestinal colic causes numerous problems and anxiety among parents, therefore knowledge of effective methods to combat this complaint is a challenge for contemporary neonatology and paediatrics.The aim of the study is to estimate the incidence of intestinal colic in newborn babies formula and breast fed as well as to assess methods of proceeding applied by parents and analyze their effectiveness.Material and methods: The research involved 100 newborn babies breast fed and 100 formula fed, and their parents. The research method applied in the study was a diagnostic survey conducted by use of a questionnaire method.Results: Among examined newborn babies that were breast fed, 43% have experienced intestinal colic, while among those formula fed 30% have suffered from it. The study involved 44% new born female babies and 56% male babies. 52% of mothers were 30-34 years old, 30% 35-59 years old, and 17% 25-59 years old. When it comes to families, the most numerous was a group in good financial situation (60%). The second numerous group was that in average financial situation (40%). All the respondents claimed that they had the knowledge on intestinal colic and the main source of knowledge was Internet (83.6%). The most frequent methods applied by the parents to combat colic are: carrying the baby (78%), belly massage (72%), and bath (63%).Conclusions: The most frequent methods to combat intestinal colic are behavioural methods and pharmacotherapy that have proved to be equally effective. According to mothers who breast feed their babies, diet was the least effective method to combat the colic

    Sustainable mini-grid

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    Abstract Paper summarized the research done in min-grid field. Mini-grid is small, stand-alone power system, which role is to provide constant and affordable electricity in remote places, where the connection with main grid is unprofitable. Mini-grids are important tools in fight with power-poverty in developing countries. The economics of power technologies is widely analyzed in different studies. The paper presents the advantages of application of integrated sustainable assessment for analyzing different power technologies for mini-grids. The paper highlight the importance of environmental and social aspects and its influence on local community

    The potential of urban agriculture for sustainability of cities in Poland

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    Town planners specialising in the sustainable development and self-sufficiency of urban areas have recently encouraged  a solution called urban agriculture, which means that urban inhabitants can produce food for themselves. The main objective of this  paper is to present the possibilities of food production in a city especially in the context of sustainable development. The idea of  crop cultivation as well as its implementation in the form of e.g. greenhouses, allotments or even gardens dates back centuries. Nevertheless,  with time and technology development, new forms of ecological farms have been designed. Urban agriculture can play an  important role in the sustainable development of cities.

    Opportunities of Power-to-Gas technology

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    This paper presents an overview of power-to-gas technologies by describing the potential, the type of technologies and the challenges that are to be faced in order to introduce them in the energy system of large areas where large shares of renewable energy have been introduced or are planned to be introduced. When large electrical grids have too large a share of intermittent renewables, there is a strong need of energy storage to balance the supply and demand with time and to avoid curtailment of renewable energy power plants. At the same time, energy storage is fundamental in small or remote grids, where the demand may be strongly different form the supply of energy during the day and during the year. In those cases reaching large shares of renewable power plants may be impossible without energy storage systems. Another important aspect that has to be studied in order to introduce energy storage systems on small or large grids, is the flexibility of operation of all power plants connected with the grid

    Constraining the double gluon distribution by the single gluon distribution

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    We show how to consistently construct initial conditions for the QCD evolution equations for double parton distribution functions in the pure gluon case. We use to momentum sum rule for this purpose and a specific form of the known single gluon distribution function in the MSTW parameterization. The resulting double gluon distribution satisfies exactly the momentum sum rule and is parameter free. We also study numerically its evolution with a hard scale and show the approximate factorization into product of two single gluon distributions at small values of x, whereas at large values of x the factorization is always violated in agreement with the sum rule.Comment: 8 pages, 2 figure
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