412 research outputs found

    Studies of Transverse Momentum Dependent Parton Distributions and Bessel Weighting

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    In this paper we present a new technique for analysis of transverse momentum dependent parton distribution functions, based on the Bessel weighting formalism. The procedure is applied to studies of the double longitudinal spin asymmetry in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator which includes quark intrinsic transverse momentum within the generalized parton model. Using a fully differential cross section for the process, the effect of four momentum conservation is analyzed using various input models for transverse momentum distributions and fragmentation functions. We observe a few percent systematic offset of the Bessel-weighted asymmetry obtained from Monte Carlo extraction compared to input model calculations, which is due to the limitations imposed by the energy and momentum conservation at the given energy/Q2. We find that the Bessel weighting technique provides a powerful and reliable tool to study the Fourier transform of TMDs with controlled systematics due to experimental acceptances and resolutions with different TMD model inputs.Comment: 30 pages, 8 figures, enhanced discussion and interpretation of results, new section on errors with an appendix, added references. Accepted for publication in JHE

    Considerations on radar localization in multi-target environments

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    In a multitude of applications like e.g. in automotive radar systems a localization of multiple passive targets in the observed area is necessary. This contribution presents a robust approach based on trilateration to detect point scatterers in a two-dimensional plane using the reflection and transmission information of only two antennas. The proposed algorithm can identify and remove ambiguities in target detection which unavoidably occur in certain target constellations in such a two-antenna configuration

    The Λp\bf{\Lambda p} interaction studied via femtoscopy in p + Nb reactions at sNN=3.18 GeV\mathbf{\sqrt{s_{NN}}=3.18} ~\mathrm{\bf{GeV}}

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    We report on the first measurement of pΛp\Lambda and pppp correlations via the femtoscopy method in p+Nb reactions at sNN=3.18 GeV\mathrm{\sqrt{s_{NN}}=3.18} ~\mathrm{GeV}, studied with the High Acceptance Di-Electron Spectrometer (HADES). By comparing the experimental correlation function to model calculations, a source size for pppp pairs of r0,pp=2.02±0.01(stat)0.12+0.11(sys) fmr_{0,pp}=2.02 \pm 0.01(\mathrm{stat})^{+0.11}_{-0.12} (\mathrm{sys}) ~\mathrm{fm} and a slightly smaller value for pΛp\Lambda of r0,Λp=1.62±0.02(stat)0.08+0.19(sys) fmr_{0,\Lambda p}=1.62 \pm 0.02(\mathrm{stat})^{+0.19}_{-0.08}(\mathrm{sys}) ~\mathrm{fm} is extracted. Using the geometrical extent of the particle emitting region, determined experimentally with pppp correlations as reference together with a source function from a transport model, it is possible to study different sets of scattering parameters. The pΛp\Lambda correlation is proven sensitive to predicted scattering length values from chiral effective field theory. We demonstrate that the femtoscopy technique can be used as valid alternative to the analysis of scattering data to study the hyperon-nucleon interaction.Comment: 12 pages, 11 figure

    Métodos y progreso de la conservación de los recursos genéticos de los olmos en Europa

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    The progress made in the conservation of European elm genetic resources since the 1st International Elm Conference is reviewed, and the complementarity of in situ and ex situ methods is discussed. The financial support of the European Union to RESGEN project CT96-78 has permitted to co-ordinate and rationalize the ex situ conservation of elms. The project, which involved 17 partner institutes in nine west European countries, aimed at a better evaluation, conservation and utilisation of the existing collections of native elm clones. Main achievements are: establishing a common database of about 2,000 clones; characterizing over 500 clones through RAPDs and chloroplast DNA PCR-RFLPs molecular markers; completing and rationalizing the existing collections; establishing a long-term core collection of 850 clones; cryo-preserving a subset of 444 clones; and identifying clones of interest for breeding and prudent use in the reconstruction of countryside hedges. The «Noble Hardwoods» network of the pan-European programme EUFORGEN groups members representative of 31 countries, and promotes the dynamic conservation of the genetic resources of several genera of broadleaf forest trees, including Ulmus spp. Strategies for the conservation of the adaptive potential of elm resources were defined and will be disseminated among foresters and conservationists through «Guidelines» leaflets. Some countries have already started implementing conservation measures for U. laevis, associating in situ preservation and the establishment of seed orchards. Others are undertaking inventories, or acquiring genetic knowledge on target populations.Se discute el progreso realizado en la conservación de los olmos europeos desde la primera conferencia Internacional del Olmo y los métodos complementarios de conservación in situ y ex situ. El apoyo financiero de la Unión Europea al proyecto RESGEN CT96-78 ha permitido coordinar y racionalizar la conservación ex situ de los olmos. El proyecto, en el cual están involucrados 17 instituciones participantes en nueve países de Europa Occidental, tiene por objetivo una mejor evaluación, conservación y utilización de las colecciones actualmente existentes de clones nativos de olmo. Los principales logros son: el establecimiento de una base de datos común de aproximadamente 2.000 clones; la caracterización de más de 500 clones usando RAPD y marcadores moleculares PCR-RFLP de ADN cloroplástico; la finalización y racionalización de las colecciones existentes; el establecimiento a largo plazo de una colección central con 850 clones; la criopreservación de un conjunto de 444 clones; y la identificación de clones de interés para la mejora y para su uso en la restauración de setos en campo. La red «Noble Hardwoods» del programa pan-europeo EUFORGEN agrupa a miembros representantes de 31 países, y promueve la conservación dinámica de los recursos genéticos de varios géneros de árboles planifolios, incluido Ulmus spp.. Las estrategias para la conservación del potencial adaptativo de los recursos de los olmos se definieron y se dieron a conocer entre forestales y conservacionistas a través de folletos guía. Algunos países han comenzado ya a implementar medidas de conservación para U. laevis mediante el uso de la preservación in situ y el establecimiento de huertos semilleros. Otros están elaborando inventarios, o adquiriendo información genética de poblaciones de interés

    Insights into the pathogenesis of ulcerative colitis from a murine model of stasis-induced dysbiosis, colonic metaplasia, and genetic susceptibility

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    Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of American Physiological Society for personal use, not for redistribution. The definitive version was published in American Journal of Physiology-Gastrointestinal and Liver Physiology 310 (2016): G973-G988, doi:10.1152/ajpgi.00017.2016.Gut dysbiosis, host genetics, and environmental triggers are implicated as causative factors in inflammatory bowel disease (IBD), yet mechanistic insights are lacking. Longitudinal analysis of ulcerative colitis patients following total colectomy with ileal anal anastomosis (IPAA) where >50% develop pouchitis, offers a unique setting to examine cause vs. effect. To recapitulate human IPAA, we employed a mouse model of surgically created blind self-filling (SFL) and self- emptying (SEL) ileal loops using wild-type (WT), IL-10 KO (IL10), and TLR4 KO (T4), and IL10/T4 double KO mice. After 5 weeks, loop histology, host gene/protein expression, and bacterial 16s rRNA profiles were examined. SFL exhibit fecal stasis due to directional motility oriented towards the loop end, whereas SEL remain empty. In wild type mice, SFL, but not SEL, develop pouch-like microbial communities without accompanying active inflammation. However, in genetically susceptible IL-10-/- deficient mice, SFL, but not SEL, exhibit severe inflammation and mucosal transcriptomes resembling human pouchitis. The inflammation associated with IL- 10-/- required TLR4, as animals lacking both pathways displayed little disease. Furthermore, germ-free IL10-/- mice conventionalized with SFL, but not SEL, microbiota populations develop severe colitis. These data support essential roles of stasis-induced, colon-like microbiota, TLR4- mediated colonic metaplasia, and genetic susceptibility in the development of pouchitis and possibly UC. However, these factors by themselves are not sufficient. Similarities between this model and human UC/pouchitis provide opportunities for gaining insights into the mechanistic basis of IBD and for identification of targets for novel preventative and therapeutic interventions.NIDDK DK42086 (DDRCC), UH3 DK083993, Leona and Harry Helmsley Trust (SHARE), R37 DK47722, T32 DK07074, F32 DK105728, Gastrointestinal Research Foundation of Chicago, Peter and Carol Goldman Family Research grant.2017-06-0

    Transverse Momentum Dependent Parton Distribution/Fragmentation Functions at an Electron-Ion Collider

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    We present a summary of a recent workshop held at Duke University on Partonic Transverse Momentum in Hadrons: Quark Spin-Orbit Correlations and Quark-Gluon Interactions. The transverse momentum dependent parton distribution functions (TMDs), parton-to-hadron fragmentation functions, and multi-parton correlation functions, were discussed extensively at the Duke workshop. In this paper, we summarize first the theoretical issues concerning the study of partonic structure of hadrons at a future electron-ion collider (EIC) with emphasis on the TMDs. We then present simulation results on experimental studies of TMDs through measurements of single spin asymmetries (SSA) from semi-inclusive deep-inelastic scattering (SIDIS) processes with an EIC, and discuss the requirement of the detector for SIDIS measurements. The dynamics of parton correlations in the nucleon is further explored via a study of SSA in D (`D) production at large transverse momenta with the aim of accessing the unexplored tri-gluon correlation functions. The workshop participants identified the SSA measurements in SIDIS as a golden program to study TMDs in both the sea and valence quark regions and to study the role of gluons, with the Sivers asymmetry measurements as examples. Such measurements will lead to major advancement in our understanding of TMDs in the valence quark region, and more importantly also allow for the investigation of TMDs in the sea quark region along with a study of their evolution.Comment: 44 pages 23 figures, summary of Duke EIC workshop on TMDs accepted by EPJ

    Advancing clinical trials for inherited retinal diseases: Recommendations from the second monaciano symposium

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    Major advances in the study of inherited retinal diseases (IRDs) have placed efforts to develop treatments for these blinding conditions at the forefront of the emerging field of precision medicine. As a result, the growth of clinical trials for IRDs has increased rapidly over the past decade and is expected to further accelerate as more therapeutic possibilities emerge and qualified participants are identified. Although guided by established principles, these specialized trials, requiring analysis of novel outcome measures and endpoints in small patient populations, present multiple challenges relative to study design and ethical considerations. This position paper reviews recent accomplishments and existing challenges in clinical trials for IRDs and presents a set of recommendations aimed at rapidly advancing future progress. The goal is to stimulate discussions among researchers, funding agencies, industry, and policy makers that will further the design, conduct, and analysis of clinical trials needed to accelerate the approval of effective treatments for IRDs, while promoting advocacy and ensuring patient safety

    Tear proteomic analysis of Sjogren syndrome patients with dry eye syndrome by two-dimensional-nano-liquid chromatography coupled with tandem mass spectrometry

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    We examined the tear film proteome of patients with Sjögren's syndrome (SS) and dry eye syndrome (group A), patients with dry eye symptoms (group B) and normal volunteers (group C). Tear samples were pooled from 8 subjects from each group and were subjected to two-dimensional-nano-liquid chromatography coupled with tandem mass spectrometry (2D-nano-LC-MS/MS). The tear breakup time for group A was significantly reduced compared with group B and C (P < 0.001). Group A (Schirmer I test, 2.13 +/- 2.38 mm/5 min) had markedly lower tear volume than group B (5.94 +/- 4.75 mm/5 min) and C (14.44 +/- 6.57 mm/5 min) (P < 0.001). Group A had significantly higher normalized tear protein content (1.8291 +/- 0.2241 mu g/mm) than group B (1.0839 +/- 0.1120 mu g/mm) (P = 0.001) and C (0.2028 +/- 0.0177 mu g/mm) (P = 0.001). The 2D-nano-LC-MS/MS analysis identified a total of 435 proteins, including 182 (54.8%),247 (74.4%) and 278 (83.7%) in group A, B, and C, respectively, with 56 (16.7%) proteins including defensin alpha 1, clusterin and lactotransferrin unique to group A. In conclusion, dry eye syndrome in SS patients is associated with an altered proteomic profile with dysregulated expression of proteins involved in a variety of important cellular process including inflammation, immunity, and oxidative stress
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