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This document summarizes the efforts of the EMMI Rapid Reaction Task Force on "Suppression and (re)generation of quarkonium in heavy-ion collisions at the LHC", centered around their 2019 and 2022 meetings. It provides a review of existing experimental results and theoretical approaches, including lattice QCD calculations and semiclassical and quantum approaches for the dynamical evolution of quarkonia in the quark-gluon plasma as probed in high-energy heavy-ion collisions. The key ingredients of the transport models are itemized to facilitate comparisons of calculated quantities such as reaction rates, binding energies, and nuclear modification factors. A diagnostic assessment of the various results is attempted and coupled with an outlook for the future. [ABSTRACT FROM AUTHOR]

We propose a parametrization of the nuclear absorption mechanism relying on the proper time spent by c c ¯ bound states travelling in nuclear matter. Our approach could lead to the extraction of charmonium formation time. It is based on a large amount of proton-nucleus data, from nucleon-nucleon center-of-mass energies s NN = 27 Ge V to s NN = 5.02 Te V , collected in the past 30 years, and for which the main effect on charmonium production must be its absorption by the nuclear matter it crosses. [ABSTRACT FROM AUTHOR]

Novel considerations are presented on the physics, apparatus and accelerator designs for a future, luminous, energy frontier electron-hadron (eh) scattering experiment at the LHC in the thirties for which key physics topics and their relation to the hadron-hadron HL-LHC physics programme are discussed. Demands are derived set by these physics topics on the design of the LHeC detector, a corresponding update of which is described. Optimisations on the accelerator design, especially the interaction region (IR), are presented. Initial accelerator considerations indicate that a common IR is possible to be built which alternately could serve eh and hh collisions while other experiments would stay on hh in either condition. A forward-backward symmetrised option of the LHeC detector is sketched which would permit extending the LHeC physics programme to also include aspects of hadron-hadron physics. The vision of a joint eh and hh physics experiment is shown to open new prospects for solving fundamental problems of high energy heavy-ion physics including the partonic structure of nuclei and the emergence of hydrodynamics in quantum field theory while the genuine TeV scale DIS physics is of unprecedented rank. [ABSTRACT FROM AUTHOR]

Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. In this contribution, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profound knowledge of the dynamical properties of the quark-gluon plasma. [ABSTRACT FROM AUTHOR]

We have carried out a wide study of shadowing and antishadowing effects on J/ ψ production in dAu collisions at $${\sqrt{s_{N N}} = 200}$$ GeV. We have studied the effects of three different gluon nPDF sets, using the exact kinematics for a 2 → 2 process, namely g + g → J/ ψ + g as expected from LO pQCD. We have computed the rapidity dependence of R and R for the different centrality classes of the PHENIX data. For mid rapidities, we have also computed the transverse-momentum dependence of the nuclear modification factor, which cannot be predicted with the usual 2 → 1 simplified kinematics. All these observables have been compared to the PHENIX data in dAu collisions. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common cause of dementia in the elderly, affecting several million of people worldwide. Pathological changes in the ADbrain include the presence of amyloid plaques, neurofibrillary tangles, loss of neurons and synapses, and oxidative damage. These changes strongly associate with mitochondrial dysfunction and stress of the endoplasmic reticulum (ER).Mitochondrial dysfunction is intimately linked to the production of reactive oxygen species (ROS) andmitochondrial-driven apoptosis, which appear to be aggravated in the brain of AD patients. Concomitantly, mitochondria are closely associated with ER, and the deleterious crosstalk between both organelles has been shown to be involved in neuronal degeneration in AD. Stimuli that enhance expression of normal and/or folding-defective proteins activate an adaptive unfolded protein response (UPR) that, if unresolved, can cause apoptotic cell death. ER stress also induces the generation of ROS that, together with mitochondrial ROS and decreased activity of several antioxidant defenses, promotes chronic oxidative stress. In this paper we discuss the critical role of mitochondrial and ER dysfunction in oxidative injury in AD cellular and animal models, as well as in biological fluids from AD patients. Progress in developing peripheral and cerebrospinal fluid biomarkers related to oxidative stress will also be summarized. [ABSTRACT FROM AUTHOR]

Amyloid-β (Aβ) peptide plays a significant role in the pathogenesis of Alzheimer's disease (AD). Previously we found that Aβ induces both mitochondrial and endoplasmic reticulum (ER) dysfunction leading to apoptosis, and now we address the relevance of ER-mitochondria crosstalk in apoptotic cell death triggered by Aβ peptide. Using mitochondrial DNA-depleted ρ0 cells derived from the human NT2 teratocarcinoma cell line, characterized by the absence of functional mitochondria, and the parental ρ+ cells, we report here that treatment with the synthetic Aβ{1-40} peptide, or the classical ER stressors thapsigargin or brefeldin A, increases GRP78 expression levels and caspase activity, two ER stress markers, and also depletes ER calcium stores. Significantly, we show that the presence of functional mitochondria is required for ER stress-mediated apoptotic cell death triggered by toxic insults such as Aβ. We found that the increase in the levels of the pro-apoptotic transcription factor GADD153/CHOP, which mediates ER stress-induced cell death, as well as caspase-9 and -3 activation and increased number of TUNEL-positive cells, occurs in treated parental ρ+ cells but is abolished in ρ0 cells. Our results strongly support the close communication between ER and mitochondria during apoptotic cell death induced by the Aβ peptide and provide insights into the molecular cascade of cell death in AD. [ABSTRACT FROM AUTHOR]

We present a new approach to estimate the effect of gluon shadowing in nucleus + nucleus collisions and its consequences on the J/ ψ production yield. Using kinematical information available from the measured J/ ψ production in proton + proton collisions at $\sqrt{s_{NN}}=200$ GeV, we build a Glauber Monte Carlo code which takes into account shadowing in two alternative ways: multiple-scattering corrections or Q2 evolution of parton densities. We exploit the dependence of these different parameterizations to the J/ ψ transverse momentum and we give the first predictions on the resulting pT dependence of the nuclear modification factor in deuteron + gold collisions at the same energy. [ABSTRACT FROM AUTHOR]

One observes strong suppression effects for hard probes, e.g. the production of J/ ψ or high- p T particles, in nucleus–nucleus ( AA) collisions at RHIC. Surprisingly, the magnitude of the suppression is quite similar to that at SPS. In order to establish whether these features arise due to the presence of a thermalized system of quarks and gluons formed in the course of the collision, one should investigate the impact of suppression mechanisms which do not explicitly involve such a state. We calculate shadowing for gluons in the Glauber–Gribov theory and propose a model invoking a rapidity-dependent absorptive mechanism motivated by energy-momentum conservation effects. Furthermore, final-state suppression due to interaction with comoving matter (hadronic or pre-hadronic) has been shown to describe the data at SPS. We extend this model by including the backward reaction channel, i.e. recombination of open charm, which is estimated directly from pp data at RHIC. Strong suppression of charmonium both in pA and AA collisions at LHC is predicted. This is in stark contrast with the predictions of models assuming QGP formation and thermalization of heavy quarks. [ABSTRACT FROM AUTHOR]

The aim of this study was to elucidate whether sulfadiazine, shown to improve cognitive capacity in the elderly, can prevent amyloid beta peptide (Aβ) (25–35)-induced impairment of the somatostatinergic system previously reported by our group in rat temporal cortex. Male Wistar rats were thus treated with sulfadiazine (160 mg/kg) or vehicle, via a gastric cannula, twice on the day prior to Aβ(25–35) treatment. On the following day and during 14 days, Aβ(25–35) was administered intracerebroventricularly (i.c.v.) via an osmotic minipump connected to a cannula implanted in the right lateral ventricle (300 pmol/day). Sulfadiazine (80 mg/kg) or vehicle was administered once again the last 2 days of the Aβ(25–35) infusion. All animals were sacrificed by decapitation 24 h after the last sulfadiazine dose. The findings obtained reveal that sulfadiazine partially prevents the decrease in somatostatin (SRIH)-like immunoreactivity content in the temporal cortex of rats infused with Aβ(25–35) during 14 days. In addition, sulfadiazine blocks the Aβ(25–35)-induced reduction in the SRIH receptor density and in SRIH receptor subtype 2 expression. Sulfadiazine treatment also restored the inhibitory effect of SRIH on basal adenylyl cyclase activity back to control values. Altogether, the results suggest that sulfadiazine might have beneficial effects in the early treatment of Alzheimer’s disease. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Education is a basic prerequisite for d/Deaf people's health. Deaf education varies considerably from country to country and we still know very little about the reasons for such variation. Objective: To identify international megatrends that influence the current Deaf bilingual education move (Deaf Bilingual—Bicultural education; DBiBi) worldwide. Methods: Using the Delphi technique, 41 experts in d/Deaf education (nine Deaf, 32 hearing) from 18 countries identified, ranked, and rated international megatrends in DBiBi education. Results: The process revealed six main essential elements of the international implementation of DBiBi education and nine main barriers against it. The top five promoting forces in that list in order of priority were: (1) societal and political changes towards a growing acceptance of diversity and Deaf issues; (2) growing Deaf activism, self-awareness and empowerment; (3) scientific research in sign linguistics and bilingualism; (4) changes in the d/Deaf educational community; and (5) international cooperation. The top five hindering forces included: (1) the view of deafness as a medical condition with a technological solution; (2) phonocentrism and societal resistance to the unknown; (3) educational and d/Deaf educational policies; (4) DBiBi education weaknesses; and (5) invisibility, heterogeneity and underperformance of the d/Deaf population. Conclusion: The results of this study reveal that social/political changes and a medical/social model of Deaf people's health can promote or limit Deaf people's educational options much more than changes within the education system itself, and that a transnational perspective is needed in deciding how best to support DBiBi education at a national and local level in an increasingly globalised world. [ABSTRACT FROM AUTHOR]

The yield of $J/\psi$ per binary nucleon-nucleon collision in AuAu and CuCu collisions at $\sqrt{s} = 200$ GeV is computed in the framework of the dual parton model, supplemented with final state interaction (comovers’ interaction). For the latter we use the same value of the cross-section, $\sigma_{\mathrm{{co}}} = 0.65$ mb, which describes the anomalous $J/\psi$ suppression observed at CERN-SPS energies. Several possibilities for the value of the absorptive cross-section are considered. Shadowing is introduced in both the comovers’ and the $J/\psi$ yields. A comparison with the results at CERN-SPS, including a prediction for InIn collisions, is also presented. [ABSTRACT FROM AUTHOR]

In the framework of percolation of color sources, the transverse momentum distribution in heavy ion andp+pcollisions at all centralities and energies are shown to follow a universal behavior. The width of the distribution depends on the fluctuations of the number of color sources per cluster. At low densities, there are only independent single color sources, no fluctuations occur and the distribution is described by a single exponential. At very high densities, only one cluster of many color sources appears and therefore there are not fluctuations either and the hardness of the distribution is suppressed. The Cronin effect in this framework is due to a maximum of the fluctuations which decreases as the density increases. We obtain a good agreement with experimental data including the lowpT behavior and the spectra for different particles. We show that the transverse momentum and multiplicity distributions are related to each other in a defined way. This point is satisfied by the experimental data onp+pcollisions at different energies. [ABSTRACT FROM AUTHOR]

We propose a model of the suppression of largepT pions in heavy ion collisions based on the interaction of the largepT pion with the dense medium created in the collision. The model is practically the same as the one previously introduced to describesuppression. Both thepT and the centrality dependence of the data are reproduced. In deuteron-gold collisions, the effect of the final state interaction with the dense medium turns out to be negligibly small. Here the main features of the data are also reproduced both at mid and at forward rapidities. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor-I (IGF-I) has protective effects againstβ-amyloid (Aβ)-induced neuronal cell death. Because alterations of the somatostatinergic system have been described in Alzheimer's disease, we investigated the effects of the Aβ peptide and the possible protective role of IGF-I on the somatostatinergic system of the rat temporal cortex and on cell death and phosphorylated (p)-Akt levels in this area. Aβ25–35 was administered intracerebroventricularly to male rats via an osmotic minipump over 14 days (300 pmol/day). Another group received a subcutaneous IGF-I infusion (50 μg/kg/day), concomitant with Aβ25–35 administration, whereas a third group received IGF-I alone. Aβ25–35 significantly decreased the somatostatin (SRIF)-like immunoreactive content and the SRIF receptor density, as a result of a decrease in the levels of the SRIF receptor subtype 2. The inhibitory effect of SRIF on adenylyl cyclase activity was significantly lower after Aβ25–35 infusion, whereas the levels of the inhibitory G protein subunit Giα1, Giα2 or Giα3 were unaltered. Cell death was increased and p-Akt levels decreased in Aβ25–35-treated animals. IGF-I administration increased immunoreactive IGF-I levels in the temporal cortex and restored all parameters affected by Aβ25–35 to baseline values. These findings suggest that IGF-I prevents the deleterious effect of Aβ25–35 on the somatostatinergic system. [ABSTRACT FROM AUTHOR]

Substance P (SP) and somatostatin (SRIF) are widely spread throughout the CNS where they play a role as neurotransmitters and/or neuromodulators. A colocalization of both neuropeptides has been demonstrated in several rat brain areas and SP receptors have been detected in rat cortical and hippocampal somatostatinergic cells. The present study was thus undertaken to determine whether SP could modulate SRIF signaling pathways in the rat frontoparietal cortex and hippocampus. A single intraperitoneal injection of SP (50, 250 or 500 µg/kg) induced an increase in the density of SRIF receptors in membranes from the rat frontoparietal cortex at 24 h of its administration, with no change in the hippocampus. The functionality of the SRIF receptors was next investigated. Western blot analysis of Gi proteins demonstrated a significant decrease in Giα[sub 1] levels in frontoparietal cortical membranes from rats treated acutely (24 h) with 250 µg/kg of SP, which correlated with a decrease in functional Gi activity, as assessed by use of the non-hydrolyzable GTP analog 5′-guanylylimidodiphosphate. SRIF-mediated inhibition of basal or forskolin-stimulated adenylyl cyclase activity was also significantly lower in the frontoparietal cortex of the SP-treated group, with no alterations in the catalytic subunit of the enzyme. SRIF-like immunoreactivity content was increased in the frontoparietal cortex after acute (24 h) SP administration (250 or 500 µg/kg) as well as in the hippocampus in response to 7 days of SP (250 µg/kg) administration. All these SP-mediated effects were prevented by pretreatment with the NK[sub 1] receptor antagonist RP-67580. Although the physiologic significance of these results are unknown, the increase in SRIF receptor density together with the desensitization of the SRIF inhibitory signaling pathway might be a mechanism to potentiate the stimulatory pathway of SRIF, inducing a preferential coupling of the receptors to PLC. [ABSTRACT FROM AUTHOR]

Summary How significant are estimates of surface areas of soils obtained by adsorption methods? To answer this we tested the applicability of an equation that relates monolayer coverage (N ) of an adsorbent with the area (A ) of adsorbate, NA z = k , for six soil samples using six adsorbates of different sizes. The data obtained confirm the validity of the equation with the z parameter ranging between 1.25 and 1.41. Hence each soil sample showed preferences towards small-sized adsorbates for which the product NA (calculated surface area) is inversely related to the size of adsorbate. We also demonstrated that the equation has roots in the Langmuir adsorption equation. [ABSTRACT FROM AUTHOR]

The process of adsorption‐desorption of the dicamba herbicide (3,6‐dichloro‐2‐methoxybenzoic acid) by 10 soils southwest of Buenos Aires (Argentine) and by calcium (Ca)‐montmorillonite, bayerite, and silica gel, was studied as a function of the applied concentration. Only two of soils studied readily adsorbed dicamba. The most important parameters in the soil with greater adsorption are low pH (5.15) and high organic matter content (5.6%). The remaining soils show negative adsorption and hydrophility of the soil colloids could account for this by preferential adsorption of water. The Ca‐montmorillonite, aluminum oxide, bayerite, and silica gel adsorbed dicamba. The extent of adsorption is small and the quantity adsorbed was characterized by Freundlich adsorption constants, which were used as an index to compare adsorbents and treatments. The analysis of the adsorption constants (k) and (1/n) shows that the reaction is irreversible and the adsorption is in the following order: bayerite > silica gel > Ca‐montmorillonite. [ABSTRACT FROM PUBLISHER]

The inclusion of string fusion in Dual Parton Model results in the appearance of diquark-antidiquark pairs in the sea with comparatively large Feynman- x. Such antidiquarks can fragment into fast antibaryons, thus increasing several times the corresponding yields in high energy pp collisions for x ∼ 0.8 ÷ 0.9. String fusion also results in an unusual dependence of inclusive spectra on the multiplicity of secondaries. Some numerical estimations are presented. [ABSTRACT FROM AUTHOR]

The KNO scaling, the scaling of multiplicities, the behaviour of fluctuations in the transverse momentum as a function of the multiplicity and the long range correlations in nucleus-nucleus collisions are studied by a Monte Carlo code based on the string fusion model. It is shown that the fusion of strings produces a strong reduction of the long range correlations at high multiplicities, which could be detected experimentally. On the contrary the KNO scaling, the scaling of multiplicities and the behaviour of fluctuations in the transverse momentum are not modified when string fusion is included. [ABSTRACT FROM AUTHOR]

Focuses on illiteracy problems in Latin America. Nonpromotion and low retention in traditional school practices; How this practice will turn the children of today into the low-literate adults of tomorrow; Suggestions on overcoming the present situation; The link between oral and written language; More.

Adsorption of eight organic molecules on kaolin, α-Fe2O3 and hydroxy-Al montmorillonite was studied to examine the effect of sorbate area on the values of the surface area of these materials. For each sorbent, the number of molecules at monolayer coverage per gram produced a single hyperbola when plotted as a function of the area occupied by an adsorbate. The equations of the hyperbolas are: NA=22.23 A0.098 for the kaolin, NA=53.70 A-0.399 for α-Fe2O3 and NA=161.81 A0.322 for the hydroxy-Al montmorillonite. These equations give accessible surface areas and not the true surface areas of the solids studied, which remain elusive. [ABSTRACT FROM AUTHOR]

The electric potentials of barley roots are explained in terms of the diffusion potentials observed with membrane concentration cells. The electromotive force of the cell and the transport numbers for K show the usual dependence on electrolyte concentration. [ABSTRACT FROM AUTHOR]

The fluctuations due to the clustering of color sources can explain the behaviour of the scaled multiplicity variance and transverse momentum fluctuations with centrality. They also predict a nonmonotonic behaviour with centrality for the multiplicity associated to high-pT events. The clustering of color sources gives rise to an increase in the long-range correlations with centrality as well as to a supression at high centrality with respect to superposition models. [ABSTRACT FROM AUTHOR]

We show that we can reproduce all the features of the bottomonium suppression in both proton-nucleus and nucleus-nucleus collisions at LHC energies in a comover-interaction picture. For each collision system, we use the measured relative suppression of the excited ϒ(2S) and ϒ(3S) states to ϒ(1S) by ATLAS and CMS to parametrise the scattering cross sections of all S- and P -wave bottomonia with the comoving particles created during the collisions. In addition to a single nonperturbative parameter, these cross sections depend on the momentum distribution of these comovers which we found to be the same for proton-nucleus and nucleus-nucleus collisions as well as for partonic and hadronic comovers. Moreover, we can also reproduce the absolute suppresion rates measured by ALICE, ATLAS, CMS and LHCb when the nuclear modifications of the parton densities are taken into account. [ABSTRACT FROM AUTHOR]

Experiments with gold-gold collisions at the RHIC have revealed (i) stronger suppression of charmonium production at forward rapidity than at mid-rapidity and (ii) the similarity between the suppression degrees at RHIC and SPS energies. To describe these findings we employ the model that includes nuclear shadowing effects, calculated within the Glauber-Gribov theory, rapidity-dependent absorptive mechanism, caused by energy-momentum conservation, and dissociation and recombination of the charmonium due to interaction with co-moving matter. The free parameters of the model are tuned and fixed by comparison with experimental data at lower energies. A good agreement with the RHIC results concerning the rapidity and centrality distributions is obtained for both heavy Au+Au and light Cu+Cu colliding systems. For pA and A+A collisions at the LHC the model predicts stronger suppression of the charmonium and bottomonium yields in stark contrast to thermal model predictions. [ABSTRACT FROM AUTHOR]