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We sympathetically cool highly charged ions (HCI) in Coulomb crystals of Doppler-cooled Be+ ions confined in a cryogenic linear Paul trap that is integrated into a fully enclosing radio-frequency resonator manufactured from superconducting niobium. By preparing a single Be+ cooling ion and a single HCI, quantum logic spectroscopy toward frequency metrology and qubit operations with a great variety of species are enabled. While cooling down the assembly through its transition temperature into the superconducting state, an applied quantization magnetic field becomes persistent, and the trap becomes shielded from subsequent external electromagnetic fluctuations. Using a magnetically sensitive hyperfine transition of Be+ as a qubit, we measure the fractional decay rate of the stored magnetic field to be at the 10−10 s−1 level. Ramsey interferometry and spin-echo measurements yield coherence times of >400 ms, demonstrating excellent passive magnetic shielding at frequencies down to DC.

We sympathetically cool highly charged ions (HCI) in Coulomb crystals of Doppler-cooled Be+ ions confined in a cryogenic linear Paul trap that is integrated into a fully enclosing radio-frequency resonator manufactured from superconducting niobium. By preparing a single Be+ cooling ion and a single HCI, quantum logic spectroscopy toward frequency metrology and qubit operations with a great variety of species are enabled. While cooling down the assembly through its transition temperature into the superconducting state, an applied quantization magnetic field becomes persistent, and the trap becomes shielded from subsequent external electromagnetic fluctuations. Using a magnetically sensitive hyperfine transition of Be+ as a qubit, we measure the fractional decay rate of the stored magnetic field to be at the 10−10 s−1 level. Ramsey interferometry and spin-echo measurements yield coherence times of >400 ms, demonstrating excellent passive magnetic shielding at frequencies down to DC.

Quantum-key-distribution (QKD) networks are gaining importance and it has become necessary to analyze the most appropriate methods for their long-distance interconnection. In this paper, four different methods of interconnecting remote QKD networks are proposed. The methods are used to link three different QKD testbeds in Europe, located in Berlin, Madrid, and Poznan. Although long-distance QKD links are only emulated, the used methods can serve as a blueprint for a secure interconnection of distant QKD networks in the future. Specifically, the presented approaches combine, in a transparent way, different fiber and satellite physical media, as well as common standards of key-delivery interfaces. The testbed interconnections are designed to increase the security by utilizing multipath techniques and multiple hybridizations of QKD and post quantum cryptography (PQC) algorithms.

This study presents a fine-scale simulation approach to assess the representativity of ammonia (NH3) measurements in the proximity of an emission source. Close proximity to emission sources (< 5 km) can introduce a bias in regionally representative measurements of the NH3 molar fraction and flux. Measurement sites should, therefore, be located a significant distance away from emission sources, but these requirements are poorly defined and can be difficult to meet in densely agricultural regions. This study presents a consistent criterion to assess the regional representativity of NH3 measurements in proximity to an emission source, calculating variables that quantify the NH3 plume dispersion using a series of numerical experiments at a fine resolution (20 m). Our fine-scale simulation framework with explicitly resolved turbulence enables us to distinguish between the background NH3 and the emission plume, including realistic representations of NH3 deposition and chemical gas–aerosol transformations. We introduce the concept of blending distance based on the calculation of turbulent fluctuations to systematically analyze the impact of the emission plume on simulated measurements, relative to this background NH3. We perform a suite of systematic numerical experiments for flat homogeneous grasslands, centered around the CESAR Observatory at Cabauw, to analyze the sensitivity of the blending distance, varying meteorological factors, emission/deposition and NH3 dependences. Considering these sensitivities, we find that NH3 measurements at this measurement site should be located at a minimum distance of 0.5–3.0 and 0.75–4.5 km from an emission source for NH3 molar fraction and flux measurements, respectively. The simulation framework presented here can easily be adapted to local conditions, and paves the way for future ammonia research to integrate simulations at high spatio-temporal resolutions with observations of NH3 concentrations and fluxes.

BACKGROUND: Sarcopenia is defined as either low pre-operative muscle mass or low muscle density on abdominal CT imaging. It has been associated with worse short-term outcomes after surgery for colorectal liver metastases. This study aimed to evaluate whether sarcopenia also impacts long-term survival outcomes in these patients.METHODS: A random-effects meta-analysis was conducted following the PRISMA guidelines. Overall survival (OS) and disease-free survival (DFS) outcomes were evaluated.RESULTS: Eleven studies were included, ten reporting on the impact of low muscle mass and four on low muscle density. Sample sizes ranged between 47 and 539 (2124 patients in total). Altogether, 897 (42%) patients were considered sarcopenic, although definitions varied between studies. Median follow-up was 21-74 months. Low muscle mass (hazard ration (HR) 1.35, 95%CI 1.08-1.68) and low muscle density (HR 1.97, 95%CI 1.07-3.62) were associated with impaired OS. Low muscle mass (pooled HR 1.17, 95%CI 0.94-1.46) and low muscle density (pooled HR 1.13, 95%CI 0.85-1.50) were not associated with impaired RFS.DISCUSSION: Sarcopenia is associated with poorer OS, but not RFS, in patients with CRLM. Additional studies with standardized sarcopenia definitions are needed to better assess the impact of sarcopenia in patients with CRLM.

BACKGROUND: Sarcopenia is associated with impaired short- and long-term outcomes in gastrointestinal cancers. Whether sarcopenia is associated with impaired survival after local therapy of Colorectal Cancer Liver Metastases (CRLM) remains controversial. This study aimed to determine the influence of sarcopenia on long-term outcomes after curative-intent therapy for CRLM.METHODS: Patients undergoing local therapy for CRLM between 2003 and 2019 were retrospectively analyzed using the skeletal muscle index at the level of the third lumbar vertebra as an indicator of sarcopenia. Factors associated with overall (OS) and disease-free (DFS) survival were analyzed using univariable and multivariable cox regression.RESULTS: In total 213/465 patients (46%) were considered sarcopenic. Sarcopenic patients had no impaired 5-year OS or DFS compared to non-sarcopenic patients, 38% vs 44% (p = 0.153) and 19 vs 23% (p = 0.339) respectively. Sarcopenia was not associated with impaired OS (HR = 1.11, 95%CI = 0.85-1.46, p = 0.43) or DFS (HR = 0.99, 95%CI = 0.77-1.28, p = 0.96) in multivariable analysis. There were no significant differences in postoperative complications (p = 0.47), the incidence (p = 0.65) and treatment (p = 0.37) of recurrent metastases. Five-year OS after resection for recurrences was 14% (sarcopenic) and 22% (non-sarcopenic) p 0.716.CONCLUSION: Sarcopenia assessed by computed tomography was not associated with impaired survival outcomes in the group of CRLM patients overall.

The Netherlands is characterized by highly variable land use within a small area, and a strong influence of the North Sea on national climate. Devoid of significant topography, it is an excellent location for assessing the relative influence of various factors on fog occurrence in the absence of terrain effects. Using observations from a dense network of weather stations throughout the country, the climatology of fog in the Netherlands is assessed over a period of 45 years. On a national scale, interannual variability is linked to changes in synoptic pressure-gradient forcing. Within the country, a comprehensive in-depth analysis of regional differences between fog occurrence is made, together with an assessment of local physical factors which could bias fog formation in one location over another. Regional variability is shown to be strongly related to the mesoscale influences of urbanization and the North Sea. In fact, some locations experience over twice as much fog as others. From this finding, a simple index is presented, which combines the water and urban fraction surrounding a station. This “Regionally Weighted Index” (RWI) is able to accurately sort the stations according to their relative fogginess. Its practical use is encouraged for assessing a given site's climatological favourability, even when in situ meteorological observations are unavailable.

This research presents two switching techniques using SOT and SLACK, as complementary sequencing rules, to show that they are practical procedures to control a job shop. These two approaches are: Static switching of the complementary rules. Dynamic switching of the complementary rules. This study also presents questions which arise in creating different switching rules or procedures for an interactive scheduling system. It is also developed a normalized objective function to measure the balance of the best properties produced by SOT (low flow time) and SLACK (low tardiness). It should be noted that even though such a system could be viewed as complex and expensive,it is not. Computational requirement will be slightly increased, but no more data is required than is expected for a typical scheduling procedure. Finally, a procedure to calculate the upper and lower limits is presented for dynamic switching procedures.