Constacyclic codes as invariant subspaces

AbstractConstacyclic codes are generalizations of the familiar linear cyclic codes. In this paper constacyclic codes over a finite field F are regarded as invariant subspaces of Fn with respect to a suitable linear operator. By applying standard techniques from linear algebra one can derive properties of these codes which generalize several well-known results for cyclic codes, such as the various lower bounds for the minimum distance

Niobium-based superconducting nano-devices fabrication using all-metal suspended masks

We report a novel method for the fabrication of superconducting nanodevices based on niobium. The well-known difficulties of lithographic patterning of high-quality niobium are overcome by replacing the usual organic resist mask by a metallic one. The quality of the fabrication procedure is demonstrated by the realization and characterization of long and narrow superconducting lines and niobium-gold-niobium proximity SQUIDs

Inflammation, carotid intima-media thickness and atherosclerosis in rheumatoid arthritis

Carotid intima-media thickness (cIMT) reflects early atherosclerosis and predicts cardiovascular events in the general population. An increased cIMT is present in patients with rheumatoid arthritis, compared with control individuals, from the early stages of the disease and is thought to indicate accelerated atherosclerosis, but direct evidence is not available. Whether cIMT is susceptible to rapid and potentially reversible change depending on the intensity of inflammation in states of high-grade systemic inflammation, such as rheumatoid arthritis, remains unknown. If this is the case, an increased cIMT in such disease states may not reflect structural vessel wall damage, and may not be a good predictor of future cardiovascular events in these particular populations. Prospective, long-term, longitudinal studies are needed to address these questions

The effect of cisatracurium infusion on the energy expenditure of critically ill patients: An observational cohort study

Background: Both overfeeding and underfeeding of intensive care unit (ICU) patients are associated with worse outcomes. A reliable estimation of the energy expenditure (EE) of ICU patients may help to avoid these phenomena. Several factors that influence EE have been studied previously. However, the effect of neuromuscular blocking agents on EE, which conceptually would lower EE, has not been extensively investigated. Methods: We studied a cohort of adult critically ill patients requiring invasive mechanical ventilation and treatment with continuous infusion of cisatracurium for at least 12 h. The study aimed to quantify the effect of cisatracurium infusion on EE (primary endpoint). EE was estimated based on ventilator-derived VCO2 (EE in kcal/day = VCO2 × 8.19). A subgroup analysis of septic and non-septic patients was performed. Furthermore, the effects of body temperature and sepsis on EE were evaluated. A secondary endpoint was hypercaloric feeding (> 110% of EE) after cisatracurium infusion. Results: In total, 122 patients were included. Mean EE before cisatracurium infusion was 1974 kcal/day and 1888 kcal/day after cisatracurium infusion. Multivariable analysis showed a significantly lower EE after cisatracurium infusion (MD - 132.0 kcal (95% CI - 212.0 to - 52.0; p = 0.001) in all patients. This difference was statistically significant in both sepsis and non-sepsis patients (p = 0.036 and p = 0.011). Non-sepsis patients had lower EE than sepsis patients (MD - 120.6 kcal; 95% CI - 200.5 to - 40.8, p = 0.003). Body temperature and EE were positively correlated (Spearman's rho = 0.486, p < 0.001). Hypercaloric feeding was observed in 7 patients. Conclusions: Our data suggest that continuous infusion of cisatracurium in mechanically ventilated ICU patients is associated with a significant reduction in EE, although the magnitude of the effect is small. Sepsis and higher body temperature are associated with increased EE. Cisatracurium infusion is associated with overfeeding in only a minority of patients and therefore, in most patients, no reductions in caloric prescription are necessary