6,069 research outputs found
Inelastic light scattering and the excited states of many-electron quantum dots
A consistent calculation of resonant inelastic (Raman) scattering amplitudes
for relatively large quantum dots, which takes account of valence-band mixing,
discrete character of the spectrum in intermediate and final states, and
interference effects, is presented. Raman peaks in charge and spin channels are
compared with multipole strengths and with the density of energy levels in
final states. A qualitative comparison with the available experimental results
is given.Comment: 5 pages, accepted in J. Phys.: Condens. Matte
Determining the nuclear neutron distribution from Coherent Elastic neutrino-Nucleus Scattering: current results and future prospects
Coherent elastic neutrino-nucleus scattering (CENS), a process recently
measured for the first time at ORNL's Spallation Neutron Source, is directly
sensitive to the weak form factor of the nucleus. The European Spallation
Source (ESS), presently under construction, will generate the most intense
pulsed neutrino flux suitable for the detection of CENS. In this paper we
quantify its potential to determine the root mean square radius of the
point-neutron distribution, for a variety of target nuclei and a suite of
detectors. To put our results in context we also derive, for the first time, a
constraint on this parameter from the analysis of the energy and timing data of
the CsI detector at the COHERENT experiment.Comment: 16 pages, 4 figures. Minor text changes and references added. Matches
version accepted by JHE
Transcending frontiers in prostate cancer: the role of oncometabolites on epigenetic regulation, CSCs, and tumor microenvironment to identify new therapeutic strategies
Prostate cancer, as one of the most prevalent malignancies in males, exhibits an approximate 5-year survival rate of 95% in advanced stages. A myriad of molecular events and mutations, including the accumulation of oncometabolites, underpin the genesis and progression of this cancer type. Despite growing research demonstrating the pivotal role of oncometabolites in supporting various cancers, including prostate cancer, the root causes of their accumulation, especially in the absence of enzymatic mutations, remain elusive. Consequently, identifying a tangible therapeutic target poses a formidable challenge. In this review, we aim to delve deeper into the implications of oncometabolite accumulation in prostate cancer. We center our focus on the consequential epigenetic alterations and impacts on cancer stem cells, with the ultimate goal of outlining novel therapeutic strategies
EUROnu-WP6 2010 Report
This is a summary of the work done by the Working Package 6 (Physics) of the
EU project "EUROnu" during the second year of activity of the project.Comment: 82 pages, 51 eps figure
Electrical neuroimaging based on biophysical constraints
This paper proposes and implements biophysical constraints to select a unique solution to the bioelectromagnetic inverse problem. It first shows that the brain's electric fields and potentials are predominantly due to ohmic currents. This serves to reformulate the inverse problem in terms of a restricted source model permitting noninvasive estimations of Local Field Potentials (LFPs) in depth from scalp-recorded data. Uniqueness in the solution is achieved by a physically derived regularization strategy that imposes a spatial structure on the solution based upon the physical laws that describe electromagnetic fields in biological media. The regularization strategy and the source model emulate the properties of brain activity's actual generators. This added information is independent of both the recorded data and head model and suffices for obtaining a unique solution compatible with and aimed at analyzing experimental data. The inverse solution's features are evaluated with event-related potentials (ERPs) from a healthy subject performing a visuo-motor task. Two aspects are addressed: the concordance between available neurophysiological evidence and inverse solution results, and the functional localization provided by fMRI data from the same subject under identical experimental conditions. The localization results are spatially and temporally concordant with experimental evidence, and the areas detected as functionally activated in both imaging modalities are similar, providing indices of localization accuracy. We conclude that biophysically driven inverse solutions offer a novel and reliable possibility for studying brain function with the temporal resolution required to advance our understanding of the brain's functional networks
Microwave heating as a novel route for obtaining carbon precursors from anthracene oil
This work describes a novel route for the preparation of pitches by oxidative polymerization of an industrial anthracene oil (AO) in a microwave semi-pilot equipment consisting in a multimode applicator having a 2.45 GHz magnetron with variable microwave power. The experimental five variables of microwave heating of AO air-blowing range between 320-380 ˚C (temperature), 0.2 - 3.9 ˚C min-1 (heating rate), 1.5 - 5 h (soaking time), 16 – 20.5 % (air/AO ratio ) and 200 – 1500 g (initial weight). Their effect on the overall microwave air-blowing process is evaluated by means of a statistical analysis. A detailed characterization of the pitches has been carried out in terms of ultimate analysis, softening point, solubility parameters (toluene insolubles (TI) and quinoline insolubles (QI)) and thermogravimetric analysis. The experiments were also carried out by using conventional heating for comparative purposes. The detailed study of the electric energy consumption of the overall microwave treatment allows estimating a significant electric energy saving of about 20 % when compared to conventional heating thus representing an excellent result in the production of carbon precursors
Non-stationary distributed source approximation: an alternative to improve localization procedures
Localization of the generators of the scalp measured electrical activity is particularly difficult when a large number of brain regions are simultaneously active. In this study, we describe an approach to automatically isolate scalp potential maps, which are simple enough to expect reasonable results after applying a distributed source localization procedure. The isolation technique is based on the time-frequency decomposition of the scalp-measured data by means of a time-frequency representation. The basic rationale behind the approach is that neural generators synchronize during short time periods over given frequency bands for the codification of information and its transmission. Consequently potential patterns specific for certain time-frequency pairs should be simpler than those appearing at single times but for all frequencies. The method generalizes the FFT approximation to the case of distributed source models with non-stationary time behavior. In summary, the non-stationary distributed source approximation aims to facilitate the localization of distributed source patterns acting at specific time and frequencies for non-stationary data such as epileptic seizures and single trial event related potentials. The merits of this approach are illustrated here in the analysis of synthetic data as well as in the localization of the epileptogenic area at seizure onset in patients. It is shown that time and frequency at seizure onset can be precisely detected in the time-frequency domain and those localization results are stable over seizures. The results suggest that the method could also be applied to localize generators in single trial evoked responses or spontaneous activity
miR-146a is a pivotal regulator of neutrophil extracellular trap formation promoting thrombosis.
Neutrophil extracellular traps (NETs) induce a procoagulant response linking inflammation and thrombosis. Low levels of miR-146a, a brake of inflammatory response, are involved in higher risk for cardiovascular events, but the mechanisms explaining how miR-146a exerts its function remain largely undefined. The aim of this study was to explore the impact of miR-146a deficiency in NETosis both, in sterile and non-sterile models in vivo, and to inquire into the underlying mechanism. Two models of inflammation were performed: 1) Ldlr-/- mice transplanted with bone marrow from miR-146a-/- or wild type (WT) were fed high-fat diet, generating an atherosclerosis model; and 2) an acute inflammation model was generated by injecting lipopolysaccharide (LPS) (1 mg/Kg) into miR-146a-/- and WT mice. miR-146a deficiency increased NETosis in both models. Accordingly, miR-146a-/- mice showed significant reduced carotid occlusion time and elevated levels of NETs in thrombi following FeCl3-induced thrombosis. Infusion of DNAse I abolished arterial thrombosis in WT and miR-146a-/- mice. Interestingly, miR-146a deficient mice have aged, hyperreactive and pro-inflammatory neutrophils in circulation that are more prone to form NETs independently of the stimulus. Furthermore, we demonstrated that community acquired pneumonia (CAP) patients with reduced miR-146a levels associated with the T variant of the functional rs2431697, presented an increased risk for cardiovascular events due in part to an increased generation of NETs.This work was supported by research grants from Instituto de Salud Carlos III (ISCIII), Fondo Europeo de Desarrollo Regional “Investing in your future” (PI17/00051 y PI17/01421) (PFIS18/0045: A.M. de los Reyes-García) (CD18/00044: S. Águila), and Fundación Séneca (19873/GERM/15). The CNIC is supported by the ISCIII, the Ministerio de Ciencia, Innovación y Universidades (MCIU), and the Fundación Pro CNIC, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). A.B. Arroyo has a research fellowship from Sociedad Española de Trombosis y Hemostasia (SETH). The MCIU supported A.dM. (predoctoral contract BES-2014-067791).S
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