Association between diet and treatment results in patients with rheumatoid arthritis and systemic lupus erythematosus

Rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) are chronic autoimmune inflammatory diseases. The causes of these diseases are unknown and evidence indicates that a combination of both genetic and environmental factors contribute to their etiology. Several studies have reported dietary benefits for patients with RA as well as SLE. Nevertheless, many of these studies have mainly focused on the dietary impact on the disease status, and the affect on treatment has not often been considered. The majority of patients with RA and SLE are dependent on treatment. Therefore, the dietary aspects in regards to treatment need to be explored further. Thus, the aim of this thesis was to examine the association between diet and treatment results in patients with RA and SLE. This thesis included five papers (Papers I-V) and was based on data of participants from three registers; Epidemiological Investigation of Rheumatoid Arthritis (EIRA), SLE Vascular Impact Cohort (SLEVIC) and Swedish Mammography Cohort (SMC). All participants from EIRA, SLEVIC and SMC were asked to complete food frequency questionnaires (FFQ) regarding their dietary habits. Dietary data from completed FFQ were linked with clinical data obtained from either Swedish Rheumatology Quality register (SRQ) or medical records. The associations between diet and clinical outcomes were analyzed with logistic regression and prospective dietary changes were analyzed with mixed models and cluster analysis. The main results of this thesis showed that 1) vitamin D and omega-3 fatty acids (FA) were associated with better response to treatment in RA patients, 2) beta-carotene (antioxidant), linoleic acid (omega-6 FA) and vitamin B6 were inversely associated with increased doses of glucocorticoids in SLE patients, 3) women who have been diagnosed with RA did not remarkably change their diet due to their disease, 4) omega 3 FA was inversely associated with non-inflammatory pain after anti-rheumatic treatment in RA patients and 5) riboflavin, phosphorus, selenium and thiamin were inversely associated with carotid plaque in SLE patients. Results from this thesis presented several associations between specific dietary nutrients and clinical outcomes of RA and SLE, in particular concerning treatment results. In summary, diet may play a role in response to anti-rheumatic treatment in patients with RA and SLE

Cracks in GaN/AlN multiple quantum well structures grown by MBE

Due to the large lattice constant mismatch and thermal expansion coefficient difference between GaN and AlN, large strain is generated inside the GaN/AlN multiple quantum wells, which causes cracks in the structure. We investigated such cracks by optical microscopy and AFM. The crack density was studied with buffer and cap layer thickness, the number of quantum well periods, and the temperature reduction rate after growth as parameters. It was found that the crack density increased exponentially, with the number of periods above 4. Besides, a very thin, 100 nm, GaN buffer layer and similar to 300 nm GaN cap layer greatly reduced the crack density

Thermal conductivity of epitaxially grown InP : experiment and simulation

Altres ajuts: Catalan AGAURThe integration of III-V optoelectronic devices on silicon is confronted with the challenge of heat dissipation for reliable and stable operation. A thorough understanding and characterization of thermal transport is paramount for improved designs of, for example, viable III-V light sources on silicon. In this work, the thermal conductivity of heteroepitaxial laterally overgrown InP layers on silicon is experimentally investigated using microRaman thermometry. By examining InP mesa-like structures grown from trenches defined by a SiO mask, we found that the thermal conductivity decreases by about one third, compared to the bulk thermal conductivity of InP, with decreasing width from 400 to 250 nm. The high thermal conductivity of InP grown from 400 nm trenches was attributed to the lower defect density as the InP microcrystal becomes thicker. In this case, the thermal transport is dominated by phonon-phonon interactions as in a low defect-density monocrystalline bulk material, whereas for thinner InP layers grown from narrower trenches, the heat transfer is dominated by phonon scattering at the extended defects and InP/SiO interface. In addition to the nominally undoped sample, sulfur-doped (1 × 10 cm) InP grown on Si was also studied. For the narrower doped InP microcrystals, the thermal conductivity decreased by a factor of two compared to the bulk value. Sources of errors in the thermal conductivity measurements are discussed. The experimental temperature rise was successfully simulated by the heat diffusion equation using the FEM

Free-Space Communications Enabled by Quantum Cascade Lasers

Future generations of wireless communication systems are expected to support orders of magnitude faster data transfer with much lower latency than the currently deployed solutions. Development of wireless transceivers of higher bandwidth, low energy consumption, and small footprint becomes challenging with radio frequency (RF) electronic technologies. Photonics-assisted technologies show many advantages in generating signals of ultrabroad bandwidth at high carrier frequencies in the millimeter-wave, terahertz, and IR bands. Among these frequency options, the mid-IR band has recently attracted great interest for future wireless communication due to its intrinsic merits of low propagation loss and high tolerance of atmospheric perturbations. A promising source for mid-IR free-space communications is the semiconductor quantum cascade laser (QCL), which can be directly modulated at a high speed and facilitates monolithic integration for compact transceivers. Herein, the research and development of QCL-based free-space communications are reviewed and a recent experimental study of multi-gigabit transmission with a directly modulated mid-IR QCL and a commercial off-the-shelf IR photodetector is reported on. Up to 4 Gb s(-1)transmission of two advanced modulation formats, namely, four-level pulse amplitude modulation (PAM-4) and discrete multitone (DMT) modulation, is demonstrated

Maskless selective growth of InGaAs/InP quantum wires on (100) GaAs

A new fabrication process to create InGaAs/InP quantum wires on (100) GaAs substrates is demonstrated. The process is based on the selectivity of the growth of InP on lines created by focused ion beam bombardment, together with the selectivity of the growth of InGaAs on the InP wires. Intense photoluminescene is observed from the wires and the emission shows clear polarization parallel and perpendicular to the wires. Cathodoluminescene images confirm that the luminescence originates from the wires.Peer reviewe

Optical and interface properties of direct InP/Si heterojunction formed by corrugated epitaxial lateral overgrowth

Producción CientíficaWe fabricate and study direct InP/Si heterojunction by corrugated epitaxial lateral overgrowth (CELOG). The crystalline quality and depth-dependent charge carrier dynamics of InP/Si heterojunction are assessed by characterizing the cross-section of grown layer by low-temperature cathodoluminescence, time-resolved photoluminescence and transmission electron microscopy. Compared to the defective seed InP layer on Si, higher intensity band edge emission in cathodoluminescence spectra and enhanced carrier lifetime of InP are observed above the CELOG InP/Si interface despite large lattice mismatch, which are attributed to the reduced threading dislocation density realized by the CELOG method.Ministerio de Economía, Industria y Competitividad (Proyect ENE2014-56069-C4-4-R)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. Project VA081U16)Swedish Energy Agency and SOLAR-ERA.NET (program 40176-1),Swedish Research Council through Linné Excellence Center ADOP

Anomalous k-dependent spin splitting in wurtzite AlxGa1-xN/GaN heterostructures

We have confirmed the k-dependent spin splitting in wurtzite AlxGa1-xN/GaN heterostructures. Anomalous beating pattern in Shubnikov-de Haas measurements arises from the interference of Rashba and Dresselhaus spin-orbit interactions. The dominant mechanism for the k-dependent spin splitting at high values of k is attributed to Dresselhaus term which is enhanced by the Delta C1-Delta C3 coupling of wurtzite band folding effect