Existence and uniqueness results for possibly singular nonlinear elliptic equations with measure data

We study existence and uniqueness of solutions to a nonlinear elliptic boundary value problem with a general, and possibly singular, lower order term, whose model is $$\begin{cases} -\Delta_p u = H(u)\mu & \text{in}\ \Omega,\\ u>0 &\text{in}\ \Omega,\\ u=0 &\text{on}\ \partial\Omega. \end{cases}$$ Here $\Omega$ is an open bounded subset of $\mathbb{R}^N$ ($N\ge2$), $\Delta_p u:= \operatorname{div}(|\nabla u|^{p-2}\nabla u)$ ($1<p<N$) is the $p$-laplacian operator, $\mu$ is a nonnegative bounded Radon measure on $\Omega$ and $H(s)$ is a continuous, positive and finite function outside the origin which grows at most as $s^{-\gamma}$, with $\gamma\ge0$, near zero

LHC Interaction region upgrade

The thesis analyzes the interaction region of the Large Hadron Collider (LHC). It proposes, studies and compares several upgrade options. The interaction region is the part of the LHC that hosts the particle detectors which analyze the collisions. An upgrade of the interaction region can po- tentially increase the number of collision events and therefore it is possible to accumulate and study a larger set of experimental data. The main object of study are the focus systems that consist of a set of magnets in charge of concentrating the particle beams in a small spot at the interaction points. The thesis uses the methods of beam optics and beam dynamics to design new interaction regions. Two design schemes are compared with a detailed analysis of the performance of several implementations. The design of the layouts takes into account the technical limitations that will affect possible realizations. Either analytical or numerical methods are used to evaluate the perfor- mance of the proposed layouts. The thesis presents new general methods that can be used for problems beyond the scope of the thesis. An analytical method has been developed for finding the intrinsic limitations of the focus systems. It allows to perform an exhaustive scan of the accessible parameter space and thus presents an efficient tool for guiding the design process. A numerical optimization routine and several enhancements have been imple- mented in MADX, a code for beam optics design. The routines simplify the solution of several optimization problems of beam optics. Keywords: accelerators design, beam optics, beam dynamics

LHC IR upgrade: a dipole first option

A dipole first option, able to reach a of 25cm, is proposed for the luminosity upgrade of LHC. Within this option only the triplets, the separation-recombination dipoles and Q5 are been upgraded. The main specifications (length, strength, aperture) for the new magnets are provided. The optical solutions with the crossing schemes for injection, collision and the transitions are found. The chromaticity correction is studied

Time Transient Effects in Superconducting Magnets

The subject of this thesis is the study of time transient effects in super- conducting cables, with applications to accelerator magnets, and the development of a simulation code. The superconducting cables are modeled at the strand level as a lumped resistor, inductor generator circuit. The analysis in time domain of the circuit currents discloses the transient effects. The code developed can solve Rutherford type cable of any size, shape geometry under any exciting external field. The code has been implemented in Roxie where it is used to compute ramp dependent field error and heat losses

A Lowgradient Triplet Quadrupole Layout Compatible with NbTi Magnet Technology and B∗\Beta^{*} = 0.25m

The paper presents a triplet layout option with long (about 100m total triplet length), low gradient (45T/m to 70T/m) quadrupole magnets. Assuming a maximum magnet diameter of 200mm, the peak coil field at the magnet coils still remains below 7T which is still compatible with conventional NbTi magnet technology. The peak beta function inside the triplet magnets reaches 22km and the configuration therefore requires an additional chromaticity correction scheme similar to a dipole first layout option. However, at the same time, the presented solution provides an interesting alternative to a high gradient triplet layout which requires the new Nb3Ti magnet technology

Direct conversion of human pluripotent stem cells into cranial motor neurons using a piggyBac vector

Human pluripotent stem cells (PSCs) are widely used for in vitro disease modeling. One of the challenges in the field is represented by the ability of converting human PSCs into specific disease-relevant cell types. The nervous system is composed of a wide variety of neuronal types with selective vulnerability in neurodegenerative diseases. This is particularly relevant for motor neuron diseases, in which different motor neurons populations show a different susceptibility to degeneration. Here we developed a fast and efficient method to convert human induced Pluripotent Stem Cells into cranial motor neurons of the branchiomotor and visceral motor subtype. These populations represent the motor neuron subgroup that is primarily affected by a severe form of amyotrophic lateral sclerosis with bulbar onset and worst prognosis. This goal was achieved by stable integration of an inducible vector, based on the piggyBac transposon, allowing controlled activation of Ngn2, Isl1 and Phox2a (NIP). The NIP module effectively produced electrophysiologically active cranial motor neurons. Our method can be easily extended to PSCs carrying disease-associated mutations, thus providing a useful tool to shed light on the cellular and molecular bases of selective motor neuron vulnerability in pathological conditions

Comparative Study of Inter-Strand Coupling Current Models for Accelerator Magnets

Inter-strand coupling currents (ISCCs) contribute to field errors and losses in Rutherford-type superconducting cables in the time-transient regime. A field change induces eddy currents in loops formed by the superconducting twisted strands and the resistive matrix. The implementation of ISCC models in ROXIE allows to combine ISCC calculations with models for persistent current sand inter- filament coupling currents. Saturation effects in iron can be taken into account as well. The predictions of different ISCC models with regard to losses and field errors are compared for two design versions of the LHC main dipole

LHC IR Upgrade: A Dipole First Option with Local Chromaticity Correction

In the framework of the LHC Luminosity Upgrade, we develop a new layout of the interaction region (IR) with b* equal to 25cm in which the combination-separation dipoles come first with respect to the triplet assembly (dipole first) in opposition of the nominal layout (quadrupole first). The new layout presents several advantages (separate channel for multipole error correction, straightforward crossing angle scheme with no crossing in the triplet, early separation of the beam). The payoff is a large b* function in the triplet, which enhances the chromaticity, non-linear effects and eats up aperture. We investigate options for local chromaticity correction and their effects on long-term stability

Quaterpyridine Ligands for Panchromatic Ru(II) Dye Sensitizers

A new general synthetic access to carboxylated quaterpyridines (qpy), of interest as ligands for panchromatic dyesensitized solar cell organometallic sensitizers, is presented. The strategic step is a Suzuki−Miyaura cross-coupling reaction, which has allowed the preparation of a number of representative unsubstituted and alkyl and (hetero)aromatic substituted qpys. To bypass the poor inherent stability of 2-pyridylboronic acid derivatives, we successfully applied N-methyliminodiacetic acid (MIDA) boronates as key reagents, obtaining the qpy ligands in good yields up to (quasi)gram quantities. The structural, spectroscopic (NMR and UV−vis), electrochemical, and electronic characteristics of the qpy have been experimentally and computationally (DFT) investigated. The easy access to the bis-thiocyanato Ru(II) complex of the parent species of the qpy series, through an efficient route which bypasses the use of Sephadex column chromatography, is shown. The bis-thiocyanato Ru(II) complex has been spectroscopically (NMR and UV−vis), electrochemically, and computationally investigated, relating its properties to those of previously reported Ru(II)−qpy complexes.“This document is the Accepted Manuscript version of a Published Work that appeared in final form in [The Journal of Organic Chemistry], copyright © American Chemical Society after peer review and technical editing by the publisher

Impact of monotherapy on HIV-1 reservoir, immune activation, and co-infection with Epstein-Barr virus

Abstract Objectives Although monotherapy (mART) effectiveness in maintaining viral suppression and CD4 cell count has been extensively examined in HIV-1-infected patients, its impact on HIV-1 reservoir, immune activation, microbial translocation and co-infection with Epstein-Barr Virus (EBV) is unclear. Methods This retrospective study involved 32 patients who switched to mART; patients were studied at baseline, 48 and 96 weeks after mART initiation. Thirty-two patients who continued combined antiretroviral therapy (cART) over the same period of time were included in the study. Markers of HIV-1 reservoir (HIV-1 DNA and intracellular HIV-1 RNA) were quantified by real-time PCR. Markers of T-(CD3(+)CD8(+)CD38(+)) and B-(CD19(+)CD80/86(+) and CD19(+)CD10-CD21(low)CD27(+)) cell activation were evaluated by flow cytometry. Plasma levels of microbial translocation markers were quantified by real-time PCR (16S ribosomal DNA and mitochondrial [mt] DNA) or by ELISA (LPS and sCD14). EBV was typed and quantified by multiplex real-time PCR. Results At baseline, no differences were found between mART and cART groups. Three (10%) mART-treated patients had a virological failure vs none in the cART group. Levels of HIV-1 DNA, intracellular HIV-1 RNA and EBV-DNA remained stable in the mART group, while decreased significantly in the cART group. Percentages of T-and B-activated cells significantly increased in the mART-treated patients, while remained at low levels in the cART-treated ones (p = 0.014 and p<0.001, respectively). Notably, levels of mtDNA remained stable in the cART group, but significantly rose in the mART one (p<0.001). Conclusions Long-term mART is associated with higher levels of T-and B-cell activation and, conversely to cART, does not reduce the size of HIV-1 reservoir and EBV co-infection