Combined atomic force microscope and electron-beam lithography used for the fabrication of variable-coupling quantum dots

We have combined direct nanofabrication by local anodic oxidation with conventional electron-beam lithography to produce a parallel double quantum dot based on a GaAs/AlGaAs heterostructure. The combination of both nanolithography methods allows to fabricate robust in-plane gates and Cr/Au top gate electrodes on the same device for optimal controllability. This is illustrated by the tunability of the interdot coupling in our device. We describe our fabrication and alignment scheme in detail and demonstrate the tunability in low-temperature transport measurements.Comment: 4 pages, 3 figure

Unravelling the clinical heterogeneity of undefined recurrent fever over time in the European registries on Autoinflammation

Background: Systemic autoinflammatory disorders (SAIDs) represent a growing spectrum of diseases characterized by dysregulation of the innate immune system. The most common pediatric autoinflammatory fever syndrome, Periodic Fever, Aphthous Stomatitis, Pharyngitis, Adenitis (PFAPA), has well defined clinical diagnostic criteria, but there is a subset of patients who do not meet these criteria and are classified as undefined autoinflammatory diseases (uAID). This project, endorsed by PRES, supported by the EMERGE fellowship program, aimed to analyze the evolution of symptoms in recurrent fevers without molecular diagnosis in the context of undifferentiated AIDs, focusing on PFAPA and syndrome of undifferentiated recurrent fever (SURF), using data from European AID registries. Methods: Data of patients with PFAPA, SURF and uSAID were collected from 3 registries including detailed epidemiological, demographic and clinical data, results of the genetic testing and additional laboratory investigations with retrospective application of the modified Marshall and PRINTO/Eurofever classification criteria on the cohort of PFAPA patients and preliminary SURF criteria on uSAID/SURF patients. Results: Clinical presentation of PFAPA is variable and some patients did not fit the conventional PFAPA criteria and exhibit different symptoms. Some patients did not meet the criteria for either PFAPA or SURF, highlighting the heterogeneity within these groups. The study also explored potential overlaps between PFAPA and SURF/uAID, revealing that some patients exhibited symptoms characteristic of both conditions, emphasizing the need for more precise classification criteria. Conclusions: Patients with recurrent fevers without molecular diagnoses represent a clinically heterogeneous group. Improved classification criteria are needed for both PFAPA and SURF/uAID to accurately identify and manage these patients, ultimately improving clinical outcomes

Structural and Magnetic Studies of Cobalt-Ferrite for Potential Pressure Sensor Applications

We have successfully synthesized CoxFe3-xO4 (x = 1) and have performed FeMössbauer, x-ray diffraction and magnetization measurements. In order to explore the potential applications of this ferrite, it is important to investigate the systematic compositional changes in structural and magnetic properties by employing the above techniques along with Raman spectroscopy and scanning electron microscopy. This will help in understanding their magneto-mechanical properties and in tuning the ferrite’s properties for magnetoelastic pressure sensors. Our interest in these materials is due to the exciting possibilities for this electrical sensor to be small, rugged, corrosion-resistant and energy efficient, unlike a mechanical pressure sensor

Structural and Magnetic Studies of Ferrite Materials for Potential Pressure Sensor Applications

Structural and magnetic analysis was carried out on the following ferrite systems: Fe-Co, FeMg, Fe-Ni, Fe-Mg-Zn, and Fe-Ni-Cu-Zn for the purpose of creating a magnetic material capable of use with a magnetoelastic pressure sensor. The compositions of each system were varied stoichiometrically and pressed into toroids. The atomic phase of each system was verified by Xray diffraction and Raman spectroscopy was applied to each ferrite in order to study their respective vibrational energy levels. Mossbauer spectroscopy was also used in order to identify the iron sites in the sample and describe the nuclear environment of the iron atoms. Each ferrite was calcined at a material specific temperature between 650° C and 700° C for one hour and then sintered at 850° C for one hour. Particle size was determined using scanning electron microscopy (SEM) and was found to be ranging from \u3c1 micron to 10 microns in diameter. Each ferrite powder was pressed into a toroid using a polyvinyl alcohol (PVA) solution as to examine each material’s inductance change in relation to the external pressure applied. Processing parameters of toroid production were varied in order to determine optimal amounts of binder and other constituents