scholarly journals Role of repulsive interactions in the interplay with missing strange resonances

2018 ◽  
Vol 171 ◽  
pp. 14001
Author(s):  
Paolo Alba

The standard implementation of the HRG model has been shown to be unable to describe all the available data on QCD matter. Here we show the balance of repulsive and attractive hadronic interactions on QCD thermodynamics through observables both calculated by lattice simulations and measured in experiment. Attractive interactions are mediated by resonance formation, which are here implemented through extra states predicted by the Quark Model, while repulsive interactions are modelled by means of Excluded Volume (EV) effects. Informations on flavour dependent effective sizes are extracted. It is found that EV effects are present in lattice QCD thermodynamics, and are essential for a comprehensive description of higher order fluctuations of conserved charges.

2018 ◽  
Vol 27 (10) ◽  
pp. 1850080
Author(s):  
Subhasis Samanta ◽  
Susil Kumar Panda ◽  
Bedangadas Mohanty

We investigate the role of suspected resonance states, that are yet to be confirmed experimentally, on different thermodynamic quantities as well as the higher-order fluctuations and the correlation between conserved charges using ideal hadron resonance gas (HRG) model. We have discussed the temperature dependence of the various thermodynamic quantities and compared them with the lattice QCD result. We observe that the values of the bulk thermodynamic variables such as pressure, energy density, entropy density and second-order susceptibilities are increased by the inclusion of the additional resonances. Further, we find that the hadronic phase of lattice QCD result of [Formula: see text] and [Formula: see text] can be described well in ideal HRG model with the additional resonances. We have also studied the [Formula: see text] dependence of the fluctuation observables of net-proton, net-kaon and net-charge. Proper experimental acceptance cuts have been used in the model to compare with the data from experimental measurements. It has been observed that the experimental data of lower-order fluctuation observable can be described well by the ideal HRG model. However, higher-order fluctuation observables cannot be described by ideal HRG model for all [Formula: see text] studied here, which indicates the possibility of presence of critical or nonequilibrium physics for those energies. The effect of additional resonances on fluctuation observables of net-charge at different [Formula: see text] has also been studied. Finally, the chemical freeze-out parameters have been extracted from the experimental data of [Formula: see text] of net-proton and net-charge using two different sets of hadronic spectra. We find that for both the sets, the extracted temperature is slightly lower than those obtained from the hadronic yields. Moreover, it is observed that the extracted temperature of the system gets further reduced with addition of more resonances.


2018 ◽  
Vol 2018 (10) ◽  
Author(s):  
Szabolcs Borsanyi ◽  
Zoltan Fodor ◽  
Jana N. Guenther ◽  
Sandor K. Katz ◽  
Attila Pasztor ◽  
...  

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1792
Author(s):  
Debashri Manna ◽  
Devanand Sarkar

Cancer development results from the acquisition of numerous genetic and epigenetic alterations in cancer cells themselves, as well as continuous changes in their microenvironment. The plasticity of cancer cells allows them to continuously adapt to selective pressures brought forth by exogenous environmental stresses, the internal milieu of the tumor and cancer treatment itself. Resistance to treatment, either inherent or acquired after the commencement of treatment, is a major obstacle an oncologist confronts in an endeavor to efficiently manage the disease. Resistance to chemotherapy, chemoresistance, is an important hallmark of aggressive cancers, and driver oncogene-induced signaling pathways and molecular abnormalities create the platform for chemoresistance. The oncogene Astrocyte elevated gene-1/Metadherin (AEG-1/MTDH) is overexpressed in a diverse array of cancers, and its overexpression promotes all the hallmarks of cancer, such as proliferation, invasion, metastasis, angiogenesis and chemoresistance. The present review provides a comprehensive description of the molecular mechanism by which AEG-1 promotes tumorigenesis, with a special emphasis on its ability to regulate chemoresistance.


2018 ◽  
Vol 75 (10) ◽  
pp. 3521-3540 ◽  
Author(s):  
Etienne Dunn-Sigouin ◽  
Tiffany Shaw

Recent work has shown that extreme stratospheric wave-1 negative heat flux events couple with the troposphere via an anomalous wave-1 signal. Here, a dry dynamical core model is used to investigate the dynamical mechanisms underlying the events. Ensemble spectral nudging experiments are used to isolate the role of specific dynamical components: 1) the wave-1 precursor, 2) the stratospheric zonal-mean flow, and 3) the higher-order wavenumbers. The negative events are partially reproduced when nudging the wave-1 precursor and the zonal-mean flow whereas they are not reproduced when nudging either separately. Nudging the wave-1 precursor and the higher-order wavenumbers reproduces the events, including the evolution of the stratospheric zonal-mean flow. Mechanism denial experiments, whereby one component is fixed to the climatology and others are nudged to the event evolution, suggest higher-order wavenumbers play a role by modifying the zonal-mean flow and through stratospheric wave–wave interaction. Nudging all tropospheric wave precursors (wave-1 and higher-order wavenumbers) confirms they are the source of the stratospheric waves. Nudging all stratospheric waves reproduces the tropospheric wave-1 signal. Taken together, the experiments suggest the events are consistent with downward wave propagation from the stratosphere to the troposphere and highlight the key role of higher-order wavenumbers.


1983 ◽  
Vol 50 (3) ◽  
pp. 658-670 ◽  
Author(s):  
A. D. McClellan

The buccal mass of the gastropod Pleurobranchaea is used during a regurgitation response that consists of a writhing phase interrupted by brief periodic bouts of a vomiting phase (17, 20). During transitions from writhing to vomiting, specific changes occur in the motor pattern (19, 20). Evidence is presented suggesting that at least some of the initiation or "command" neurons for vomiting reside in the buccal ganglia. The present paper examines the role of two candidate vomiting-initiation cells, the ventral white cells (VWC) and midganglionic cells (MC), in the buccal ganglia of isolated nervous systems. Stimulation of single VWCs activates a vomiting motor pattern, consisting in part of alternating buccal root activity. Furthermore, the VWCs fire in high-frequency bursts during episodes (i.e., bouts) of this same vomiting pattern. Mutual reexcitation between the VWCs and motor pattern generator (MPG) appears to produce the accelerated buildup and maintenance of vomiting rhythms. Brief stimulation of single MCs "triggers" bouts of a vomiting motor pattern, but the membrane potential of this cell is only modulated during this same pattern, at least in the isolated nervous system. It is proposed that in intact animals the MCs are activated by sensory inputs and briefly excite the VWC-MPG network, thereby turning on the mutual reexcitatory mechanism mentioned above and switching the output pattern. A general implication for gastropod research is that higher order neurons that activate buccal root activity cannot automatically be given the function of "feeding command neuron," as some cells clearly control other responses, such as vomiting.


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