1,574 research outputs found
Deconfinement and degrees of freedom in and collisions at LHC energies
We present the extraction of the temperature by analyzing the charged
particle transverse momentum spectra in lead-lead (Pb-Pb) and proton-proton
() collisions at LHC energies from the ALICE Collaboration using the
Color String Percolation Model (CSPM). From the measured energy density and the temperature T the dimensionless quantity is obtained to get the degrees of freedom (DOF), = DOF /30.
We observe for the first time a two-step behavior in the increase of DOF,
characteristic of deconfinement, above the hadronization temperature at
temperature 210 MeV for both Pb-Pb and collisions and a
sudden increase to the ideal gas value of 47 corresponding to three
quark flavors in the case of Pb-Pb collisions.Comment: 7 pages and 4 figure
Development of Physical Fitness among the Top 10 Boys and Girls in Sport Schools: A 10-Year Cohort Analysis
In this study, we aimed to measure the development of physical fitness (PF) of 10 different cohorts in grade 4 and 8 different cohorts in grade 7 at 18 sport schools of North Rhine-Westphalia, Germany. A total of 11,451 subjects (3979 female, 7472 male) aged 8–12 from the past 10 years were assessed using the German Motor Test (DMT) in grade 4. We tested 2614 subjects (1032 girls, 1582 boys) aged 11–15 from the past eight years using the DMT in grade 7. PF talents were defined as the top 10 boys and top 10 girls of each cohort. Linear regression was calculated to assess the development of PF. The PF of all subjects remained stable in grade 4 and declined in grade 7. The PF of the top 10 boys and top 10 girls increased in both grades. The improvements were stronger in grade 7 (female: rates of change () = 0.80; male: = 0.76) than in grade 4 (female: = 0.36; male: = 0.32). Sit-ups and push-ups showed the highest change rates. The increase in PF of the top 10 boys and girls can be interpreted as a success for sport schools. Due to the increasing number of test participants, the likelihood of finding top talent increased. However, the increase in PF in the top talents was only partly explained by an increase in the number of tested individuals
Long range correlations, event simulation and parton percolation
We study the RHIC data on long range rapidity correlations, comparing their
main trends with different string model simulations. Particular attention is
paid to color percolation model and its similarities with color glass
condensate. As both approaches corresponds, at high density, to a similar
physical picture, both of them give rise to a similar behavior on the energy
and the centrality of the main observables. Color percolation explains the
transition from low density to high density.Comment: Contribution to the meeting : Saturation, the CGC and the Glasma BNL.
May 10-12, accepted in Nuclear Physics
TRPM7 Provides an Ion Channel Mechanism for Cellular Entry of Trace Metal Ions
Trace metal ions such as Zn2+, Fe2+, Cu2+, Mn2+, and Co2+ are required cofactors for many essential cellular enzymes, yet little is known about the mechanisms through which they enter into cells. We have shown previously that the widely expressed ion channel TRPM7 (LTRPC7, ChaK1, TRP-PLIK) functions as a Ca2+- and Mg2+-permeable cation channel, whose activity is regulated by intracellular Mg2+ and Mg2+·ATP and have designated native TRPM7-mediated currents as magnesium-nucleotide–regulated metal ion currents (MagNuM). Here we report that heterologously overexpressed TRPM7 in HEK-293 cells conducts a range of essential and toxic divalent metal ions with strong preference for Zn2+ and Ni2+, which both permeate TRPM7 up to four times better than Ca2+. Similarly, native MagNuM currents are also able to support Zn2+ entry. Furthermore, TRPM7 allows other essential metals such as Mn2+ and Co2+ to permeate, and permits significant entry of nonphysiologic or toxic metals such as Cd2+, Ba2+, and Sr2+. Equimolar replacement studies substituting 10 mM Ca2+ with the respective divalent ions reveal a unique permeation profile for TRPM7 with a permeability sequence of Zn2+ ≈ Ni2+ >> Ba2+ > Co2+ > Mg2+ ≥ Mn2+ ≥ Sr2+ ≥ Cd2+ ≥ Ca2+, while trivalent ions such as La3+ and Gd3+ are not measurably permeable. With the exception of Mg2+, which exerts strong negative feedback from the intracellular side of the pore, this sequence is faithfully maintained when isotonic solutions of these divalent cations are used. Fura-2 quenching experiments with Mn2+, Co2+, or Ni2+ suggest that these can be transported by TRPM7 in the presence of physiological levels of Ca2+ and Mg2+, suggesting that TRPM7 represents a novel ion-channel mechanism for cellular metal ion entry into vertebrate cells
Scaling in the Lattice Gas Model
A good quality scaling of the cluster size distributions is obtained for the
Lattice Gas Model using the Fisher's ansatz for the scaling function. This
scaling identifies a pseudo-critical line in the phase diagram of the model
that spans the whole (subcritical to supercritical) density range. The
independent cluster hypothesis of the Fisher approach is shown to describe
correctly the thermodynamics of the lattice only far away from the critical
point.Comment: 4 pages, 3 figure
Novel reporter systems for facile evaluation of I-SceI-mediated genome editing
Two major limitations to achieve efficient homing endonuclease-stimulated gene correction using retroviral vectors are low frequency of gene targeting and random integration of the targeting vectors. To overcome these issues, we developed a reporter system for quick and facile testing of novel strategies to promote the selection of cells that undergo targeted gene repair and to minimize the persistence of random integrations and non-homologous end-joining events. In this system, the gene target has an I-SceI site upstream of an EGFP reporter; and the repair template includes a non-functional EGFP gene, the positive selection transgene MGMTP140K tagged with mCherry, and the inducible Caspase-9 suicide gene. Using this dual fluorescent reporter system it is possible to detect properly targeted integration. Furthermore, this reporter system provides an efficient approach to enrich for gene correction events and to deplete events produced by random integration. We have also developed a second reporter system containing MGMTP140K in the integrated target locus, which allows for selection of primary cells with the integrated gene target after transplantation. This system is particularly useful for testing repair strategies in primary hematopoietic stem cells. Thus, our reporter systems should allow for more efficient gene correction with less unwanted off target effects
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