356 research outputs found

    Driving Rydberg-Rydberg transitions from a co-planar microwave waveguide

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    The coherent interaction between ensembles of helium Rydberg atoms and microwave fields in the vicinity of a solid-state co-planar waveguide is reported. Rydberg-Rydberg transitions, at frequencies between 25 GHz and 38 GHz, have been studied for states with principal quantum numbers in the range 30 - 35 by selective electric-field ionization. An experimental apparatus cooled to 100 K was used to reduce effects of blackbody radiation. Inhomogeneous, stray electric fields emanating from the surface of the waveguide have been characterized in frequency- and time-resolved measurements and coherence times of the Rydberg atoms on the order of 250 ns have been determined.Comment: 5 pages, 5 figure

    Imaging electric fields in the vicinity of cryogenic surfaces using Rydberg atoms

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    The ability to characterize static and time-dependent electric fields in situ is an important prerequisite for quantum-optics experiments with atoms close to surfaces. Especially in experiments which aim at coupling Rydberg atoms to the near field of superconducting circuits, the identification and subsequent elimination of sources of stray fields is crucial. We present a technique that allows the determination of stray-electric-field distributions (Fxstr(r),Fystr(r),Fzstr(r))(F^\text{str}_\text{x}(\vec{r}),F^\text{str}_\text{y}(\vec{r}),F^\text{str}_\text{z}(\vec{r})) at distances of less than 2 mm2~\text{mm} from (cryogenic) surfaces using coherent Rydberg-Stark spectroscopy in a pulsed supersonic beam of metastable 1s12s1 1S01\text{s}^12\text{s}^1~{}^{1}S_{0} helium atoms. We demonstrate the capabilities of this technique by characterizing the electric stray field emanating from a structured superconducting surface. Exploiting coherent population transfer with microwave radiation from a coplanar waveguide, the same technique allows the characterization of the microwave-field distribution above the surface.Comment: 6 pages, 4 figure

    Measuring the dispersive frequency shift of a rectangular microwave cavity induced by an ensemble of Rydberg atoms

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    In recent years the interest in studying interactions of Rydberg atoms or ensembles thereof with optical and microwave frequency fields has steadily increased, both in the context of basic research and for potential applications in quantum information processing. We present measurements of the dispersive interaction between an ensemble of helium atoms in the 37s Rydberg state and a single resonator mode by extracting the amplitude and phase change of a weak microwave probe tone transmitted through the cavity. The results are in quantitative agreement with predictions made on the basis of the dispersive Tavis-Cummings Hamiltonian. We study this system with the goal of realizing a hybrid between superconducting circuits and Rydberg atoms. We measure maximal collective coupling strengths of 1 MHz, corresponding to 3*10^3 Rydberg atoms coupled to the cavity. As expected, the dispersive shift is found to be inversely proportional to the atom-cavity detuning and proportional to the number of Rydberg atoms. This possibility of measuring the number of Rydberg atoms in a nondestructive manner is relevant for quantitatively evaluating scattering cross sections in experiments with Rydberg atoms

    Metal arc welding and the risk of skin cancer

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    Fixed-ratio combination of insulin degludec and liraglutide (IDegLira) improves cardiovascular risk markers in patients with type 2 diabetes uncontrolled on basal insulin

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    In this post hoc analysis we investigated the effects of insulin degludec/liraglutide fixed-ratio combination (IDegLira) versus comparators on cardiovascular (CV) risk markers in participants in the DUAL II (vs. insulin degludec), DUAL V (vs. insulin glargine 100 units/mL) and DUAL VII (vs. basal-bolus therapy) trials, grouped by sex, age (<65 years, ≥65 years) and diabetes duration (<10 years, ≥10 years). Treatment contrasts were in favour of IDegLira in many subgroups for changes from baseline in glycated haemoblogin (DUAL II, DUAL V), body weight (all three trials), systolic blood pressure (BP; all three trials), HDL cholesterol (DUAL VII) and LDL cholesterol (DUAL II, DUAL V). Higher heart rates were seen with IDegLira versus comparators (all three trials) plus significantly higher diastolic BP in men (DUAL V). Differences in treatment effect were seen between sexes in waist circumference (DUAL II), systolic BP (DUAL II, DUAL V) and triglycerides (DUAL VII), and between diabetes durations in LDL cholesterol (DUAL V). In conclusion, IDegLira is associated with a general improvement in CV risk markers compared with basal insulin or basal-bolus therapy after 26 weeks of treatment

    Current knowledge on biomarkers for contact sensitization and allergic contact dermatitis.

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    Contact sensitization is common and affects up to 20% of the general population. The clinical manifestation of contact sensitization is allergic contact dermatitis. This is a clinical expression that is sometimes difficult to distinguish from other types of dermatitis, for example irritant and atopic dermatitis. Several studies have examined the pathogenesis and severity of allergic contact dermatitis by measuring the absence or presence of various biomarkers. In this review, we provide a non-systematic overview of biomarkers that have been studied in allergic contact dermatitis. These include genetic variations and mutations, inflammatory mediators, alarmins, proteases, immunoproteomics, lipids, natural moisturizing factors, tight junctions, and antimicrobial peptides. We conclude that, despite the enormous amount of data, convincing specific biomarkers for allergic contact dermatitis are yet to be described

    Chronic hand eczema in Europe:Patient experiences and perspectives (CHEPEP) in qualitative interviews

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    Background: Chronic hand eczema (CHE) is a very common skin disease among the European population. It causes itch and pain and, in more severe cases, seriously impairs hand functioning at work and in private life. Objectives: To explore perspectives of people with lived experience on CHE-related problems, wishes and goals. Methods: Following a qualitative approach, we conducted topic-guided interviews in five European countries and applied template analysis to identify recurrent themes among patients with CHE. Results: We interviewed 60 patients in seven outpatient dermatological and occupational medicine clinics in Croatia, Denmark, Germany, the Netherlands and Spain. Five main themes were identified: (1) knowledge about the disease and its course, (2) preventive behaviour, (3) hand eczema therapy, (4) impact on everyday life and (5) attitudes towards CHE and healthcare. Participants did not feel well informed about CHE, especially about causes, triggers and treatment options. Preventive measures were experienced as more or less effective but also cumbersome. Experiences with therapy were diverse. Treatment satisfaction depended on the results and on the perceived support from the treatment teams. Participants found it important to be taken seriously, to receive practical advice, to try out additional treatments or examinations, find new hope and have occupational perspectives. They wished that others could better understand the physical and emotional burden of CHE. Patient support groups were not mentioned. Participants found it important to learn to take care of themselves and accept life with CHE. Conclusions: Due to its annoying symptoms, high visibility and impaired functioning at work and in private life, CHE has a high emotional and social impact. Some people may require support to learn coping with CHE and its prevention. Patients wish for information about causes and triggers. They value physicians who listen to them and keep looking for solutions.</p

    The relevance of model-driven engineering thirty years from now

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    International audienceAlthough model-driven engineering (MDE) is now an established approach for developing complex software systems, it has not been universally adopted by the software industry. In order to better understand the reasons for this, as well as to identify future opportunities for MDE, we carried out a week-long design thinking experiment with 15 MDE experts. Participants were facilitated to identify the biggest problems with current MDE technologies, to identify grand challenges for society in the near future, and to identify ways that MDE could help to address these challenges. The outcome is a reflection of the current strengths of MDE, an outlook of the most pressing challenges for society at large over the next three decades, and an analysis of key future MDE research opportunities

    Evidence-Based Management of Hand Eczema

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    Hand eczema is a common skin disease with a wide variation in morphology and a complex etiology based on endogenous and exogenous factors.The diagnosis of hand eczema is based on patient history, exposure assessment, physical examination, and the results of patch testing. Management of hand eczema starts with education of the patient on the etiology of the disease, and the needed changes in behavior regarding skin care and preventive measures, and avoidance of relevant exposure factors. In many cases, medical treatment is needed for successful management of the disease; use of medication can only be successful with proper education and avoidance of relevant exposure
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