2,683 research outputs found
The performance of the ALICE TOF detector
The performances of the ALICE Time Of Flight detector are presented, based on the 2010 data taking. Hardware status, time resolution and PID capability are shown and compared with the design values. First results in Pb-Pb at √sNN = 2.76TeV are reported
A probability-conserving cross-section biasing mechanism for variance reduction in Monte Carlo particle transport calculations
In Monte Carlo particle transport codes, it is often important to adjust
reaction cross sections to reduce the variance of calculations of relatively
rare events, in a technique known as non-analogous Monte Carlo. We present the
theory and sample code for a Geant4 process which allows the cross section of a
G4VDiscreteProcess to be scaled, while adjusting track weights so as to
mitigate the effects of altered primary beam depletion induced by the cross
section change. This makes it possible to increase the cross section of nuclear
reactions by factors exceeding 10^4 (in appropriate cases), without distorting
the results of energy deposition calculations or coincidence rates. The
procedure is also valid for bias factors less than unity, which is useful, for
example, in problems that involve computation of particle penetration deep into
a target, such as occurs in atmospheric showers or in shielding
The development of juvenile stages of Xiphinema index (Nematoda : Dorylaimida) on Vitis vinifera
Flux creep in Bi2Sr2Ca1Cu2O(8+x) single crystals
Dissipative effects were investigated in Bi2Sr2Ca1Cu2O(8+x) single crystals by critical current and magnetic relaxation measurements. Activation energies for the flux motion were determined from the temperature dependence of the critical current and from the time decay of the zero field cooled and the remanent magnetization. The effective activation energy was found to increase with temperature, in agreement with the existence of a distribution of activation energies (E sub o 20 meV at 4.2 K for H + 10 kOe applied parallel to the c-axis.)
A time-resolution study with a plastic scintillator read out by a Geiger-mode Avalanche Photodiode
In this work we attempt to establish the best time resolution attainable with
a scintillation counter consisting of a plastic scintillator read out by a
Geiger-mode Avalanche Photodiode. The measured time resolution is inversely
proportional to the square root of the energy deposited in the scintillator,
and scales to 18ps (sigma) at 1MeV. This result competes with the best ones
reported for photomultiplier tubes.Comment: 8 pages, 8 figure
An Algorithm for Computing Screened Coulomb Scattering in Geant4
An algorithm has been developed for the Geant4 Monte-Carlo package for the
efficient computation of screened Coulomb interatomic scattering. It explicitly
integrates the classical equations of motion for scattering events, resulting
in precise tracking of both the projectile and the recoil target nucleus. The
algorithm permits the user to plug in an arbitrary screening function, such as
Lens-Jensen screening, which is good for backscattering calculations, or
Ziegler-Biersack-Littmark screening, which is good for nuclear straggling and
implantation problems. This will allow many of the applications of the TRIM and
SRIM codes to be extended into the much more general Geant4 framework where
nuclear and other effects can be included.Comment: 19 pages, 6 figures; corrected to rerferee comments, typo in equation
5 fixe
Flux creep in Bi2Sr2CaCu2O8(sub +x) single crystals
The results of a magnetic study on a Bi2Sr2CaCu2O(8+x) single crystal are reported. Low field susceptibility (dc and ac), magnetization cycles and time dependent measurements were performed. With increasing the temperature the irreversible regime of the magnetization cycles is rapidly restricted to low fields, showing that the critical current J(sub c) becomes strongly field dependent well below T(sub c). At 2.4 K the critical current in zero field, determined from the remanent magnetization by using the Bean formula for the critical state, is J(sub c) = 2 10(exp 5) A/sq cm. The temperature dependence of J(sub c) is satisfactorily described by the phenomenological law J(sub c) = J(sub c) (0) (1 - T/T(sub c) (sup n), with n = 8. The time decay of the zero field cooled magnetization and of the remanent magnetization was studied at different temperatures for different magnetic fields. The time decay was found to be logarithmic in both cases, at least at low temperatures. At T = 4.2 K for a field of 10 kOe applied parallel to the c axis, the average pinning energy, determined by using the flux creep model, is U(sub o) = 0.010 eV
Glucose, glutathione, and cellular response to spermine oxidation products
Bovine serum amineoxidase (BSAO) oxidatively deaminates polyamines, which contain primary amine groups with formation of several toxic products, H2O2, and aldehyde(s). We evaluated the role of glucose metabolism via the pentose phosphate cycle and the level of intracellular glutathione on cytotoxicity induced by each of the toxic products in Chinese hamster ovary (CHO) cells. Glucose protected cells against cytotoxicity in the presence of BSAO at low spermine concentrations (< 50 mu M), where H2O2 was the only toxic species present. When catalase was present, cytotoxicity is attributed to spermine-derived aldehyde(s). Glucose did not protect cells against cytotoxicity induced by spermine-derived aldehyde(s), nor by the aldehyde acrolein. Hydrogen peroxide produced by spermine and BSAO stimulated pentose cycle activity, whereas the aldehyde(s) did not. Depletion of intracellular glutathione with L-buthionine sulfoximine (1 mM, 24 h) sensitized cells to the cytotoxic effects of both H2O2 and the aldehyde(s) produced by spermine and BSAO. The pentose cycle and the glutathione redox cycle have an important role in protection against H2O2 generated from spermine oxidation. Glutathione appears to have a role in protecting cells against cytotoxicity attributed to spermine-derived aldehyde(s), most likely by conjugation in a reaction catalyzed by glutathione S-transferase, whereas metabolism of glucose via the pentose cycle did not. The metabolism of both glucose and glutathione, affect the cellular response to H2O2 and aldehyde(s) derived from spermine, although different pathways are involved
Automated Generation of Executable RPA Scripts from User Interface Logs
Robotic Process Automation (RPA) operates on the user interface (UI) of software applications and automates - by means of a software (SW) robot - mouse and keyboard interactions to remove intensive routine tasks (or simply routines). With the recent advances in Artificial Intelligence, the automation of routines is expected to undergo a radical transformation. Nonetheless, to date, the RPA tools available in the market are not able to automatically learn to automate such routines, thus requiring the support of skilled human experts that observe and interpret how routines are executed on the UIs of the applications. Being the current practice time-consuming and error-prone, in this paper we present SmartRPA, a cross-platform tool that tackles such issues by exploiting UI logs to automatically generate executable RPA scripts that automate the routines enactment by SW robots
Protein kinase CK2 is widely expressed in follicular, Burkitt and diffuse large B-cell lymphomas and propels malignant B-cell growth.
Serine-threonine kinase CK2 is highly expressed and pivotal for survival and proliferation in multiple myeloma, chronic lymphocytic leukemia and mantle cell lymphoma. Here, we investigated the expression of \u3b1 catalytic and \u3b2 regulatory CK2 subunits by immunohistochemistry in 57 follicular (FL), 18 Burkitt (BL), 52 diffuse large B-cell (DLBCL) non-Hodgkin lymphomas (NHL) and in normal reactive follicles. In silico evaluation of available Gene Expression Profile (GEP) data sets from patients and Western blot (WB) analysis in NHL cell-lines were also performed. Moreover, the novel, clinical-grade, ATP-competitive CK2-inhibitor CX-4945 (Silmitasertib) was assayed on lymphoma cells. CK2 was detected in 98.4% of cases with a trend towards a stronger CK2\u3b1 immunostain in BL compared to FL and DLBCL. No significant differences were observed between Germinal Center B (GCB) and non-GCB DLBCL types. GEP data and WB confirmed elevated CK2 mRNA and protein levels as well as active phosphorylation of specific targets in NHL cells. CX-4945 caused a dose-dependent growth-arresting effect on GCB, non-GCB DLBCL and BL cell-lines and it efficiently shut off phosphorylation of NF-\u3baB RelA and CDC37 on CK2 target sites. Thus, CK2 is highly expressed and could represent a suitable therapeutic target in BL, FL and DLBCL NHL
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