126 research outputs found
Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor
We report on the fabrication and characterization of a few-electron quantum
dot controlled by a single gate electrode. Our device has a double-quantum-well
design, in which the doping controls the occupancy of the lower well while the
upper well remains empty under the free surface. A small air-bridged gate
contacts the surface, and is positively biased to draw laterally confined
electrons into the upper well. Electrons tunneling between this
accumulation-mode dot and the lower well are detected using a quantum point
contact (QPC), located slightly offset from the dot gate. The charge state of
the dot is measured by monitoring the differential transconductance of the QPC
near pinch-off. Addition spectra starting with N=0 were observed as a function
of gate voltage. DC sensitivity to single electrons was determined to be as
high as 8.6%, resulting in a signal-to-noise ratio of ~9:1 with an equivalent
noise bandwidth of 12.1 kHz. Analysis of random telegraph signals associated
with the zero to one electron transition allowed a measurement of the lifetimes
for the filled and empty states of the one-electron dot: 0.38 ms and 0.22 ms,
respectively, for a device with a 10 nm AlInAs tunnel barrier between the two
wells.Comment: 3 pages, 3 figure
Wide Range Applications of Spirulina: From Earth to Space Missions
Spirulina is the most studied cyanobacterium species for both pharmacological applications and the food industry. The aim of the present review is to summarize the potential benefits of the use of Spirulina for improving healthcare both in space and on Earth. Regarding the first field of application, Spirulina could represent a new technology for the sustainment of long-duration manned missions to planets beyond the Lower Earth Orbit (e.g., Mars); furthermore, it could help astronauts stay healthy while exposed to a variety of stress factors that can have negative consequences even after years. As far as the second field of application, Spirulina could have an active role in various aspects of medicine, such as metabolism, oncology, ophthalmology, central and peripheral nervous systems, and nephrology. The recent findings of the capacity of Spirulina to improve stem cells mobility and to increase immune response have opened new intriguing scenarios in oncological and infectious diseases, respectively
A Real-Life Study on the Use of Tildrakizumab in Psoriatic Patients
tildrakizumab is a humanized IgG1 kappa monoclonal antibody that selectively targets the p19 subunit of interleukin IL-23, thereby inhibiting the IL-23/IL-17 axis, which is primarily implicated in the immunopathogenesis of psoriasis. Tildrakizumab is approved for the treatment of moderate-to-severe plaque-type psoriasis in adults based on the evidence of two randomized and controlled phase-III clinical trials (reSURFACE 1 and reSURFACE 2). Here, we report our real-life experience treating 53 psoriatic patients (19 female and 34 male) who were administered tildrakizumab every 12 weeks and received follow-ups over 52 weeks. descriptive and inferential statistical analyses were performed, in particular the psoriasis area and severity Index (PASI), dermatology life quality Index (DLQI) and, if applicable, the Nail Psoriasis Severity Index (NAPSI) and Palmoplantar psoriasis physician global assessment (PPPGA). these were assessed at baseline and after different timepoints (weeks) during the follow-up period. we described and evaluated demographical and epidemiological characteristics in our cohort group, focusing on comorbidities. In this group, 35.9% of patients were female and 64.1% were male, with 47.1% being smokers and with a mean age of 51.2 years. a total of 37.7% of these patients was affected by scalp psoriasis; regarding comorbidities, hypertension was the most frequent (32.5%), followed by psoriatic arthritis (PsA) (18.60%) and diabetes (13.9%). at week 52, 93%, 90.2% and 77% of patients achieved a PASI reduction >= 75% (PASI 75), PASI 90 and PASI 100, respectively. In addition, NAPSI, PPPGA and DLQI scores were significantly reduced by week 52. In our cohort of complex psoriasis patients, disease remission began at the end of the fourth week of treatment and remained constant from week 16 to week 52
Dispersively detected Pauli Spin-Blockade in a Silicon Nanowire Field-Effect Transistor
We report the dispersive readout of the spin state of a double quantum dot
formed at the corner states of a silicon nanowire field-effect transistor. Two
face-to-face top-gate electrodes allow us to independently tune the charge
occupation of the quantum dot system down to the few-electron limit. We measure
the charge stability of the double quantum dot in DC transport as well as
dispersively via in-situ gate-based radio frequency reflectometry, where one
top-gate electrode is connected to a resonator. The latter removes the need for
external charge sensors in quantum computing architectures and provides a
compact way to readout the dispersive shift caused by changes in the quantum
capacitance during interdot charge transitions. Here, we observe Pauli
spin-blockade in the high-frequency response of the circuit at finite magnetic
fields between singlet and triplet states. The blockade is lifted at higher
magnetic fields when intra-dot triplet states become the ground state
configuration. A lineshape analysis of the dispersive phase shift reveals
furthermore an intradot valley-orbit splitting of 145 eV.
Our results open up the possibility to operate compact CMOS technology as a
singlet-triplet qubit and make split-gate silicon nanowire architectures an
ideal candidate for the study of spin dynamics
Mechanisms of Degradation and Identification of Connectivity and Erosion Hotspots
The context of processes and characteristics of soil erosion and land degradation in Mediterranean lands is outlined. The concept of connectivity is explained. The remainder of the chapter demonstrates development of methods of mapping, analysis and modelling of connectivity to produce a spatial framework for development of strategies of use of vegetation to reduce soil erosion and land degradation. The approach is applied in a range of typical land use types and at a hierarchy of scale from land unit to catchment. Patterns of connectivity and factors influencing the location and intensity of processes are identified, including the influence of topography, structures such as agricultural terraces and check dams, and past land uses. Functioning of connectivity pathways in various rainstorms is assessed. Modes of terrace construction and extent of maintenance, as well as presence of tracks and steep gradients are found to be of importance. A method of connectivity modelling that incorporates effects of structure and vegetation was developed and has been widely applied subsequently
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