443 research outputs found
From electronic structure to catalytic activity: A single descriptor for adsorption and reactivity on transition-metal carbides
Adsorption and catalytic properties of the polar (111) surface of
transition-metal carbides (TMC's) are investigated by density-functional
theory. Atomic and molecular adsorption are rationalized with the
concerted-coupling model, in which two types of TMC surface resonances (SR's)
play key roles. The transition-metal derived SR is found to be a single
measurable descriptor for the adsorption processes, implying that the
Br{\o}nsted-Evans-Polanyi relation and scaling relations apply. This gives a
picture with implications for ligand and vacancy effects and which has a
potential for a broad screening procedure for heterogeneous catalysts.Comment: 5 pages, 3 figure
Diagnostic value of presepsin for bacterial infection in cirrhosis: a pilot study
Introduction: Presepsin (or sCD14) has been identified as a protein whose levels increase specifically in the blood of patients with bacterial infections. In this study, we evaluated the clinical performance of sCD14 and its usefulness in the early diagnosis of bacterial infection in decompensated cirrhotic patients. Materials: Seventy patients were enrolled in this study. The mean age of patients was 49.5 years, and 21 were women and 49 men. The heparinized whole blood for the PATHFAST test was used in the evaluation of bacterial infection (T0). The test was repeated after 48 hours (T1); at 96 hours (T2); at 144 hours (T3); then at 15 days (T4) to monitor the clinical responses to therapeutic interventions. Results: Forty-nine patients tested positive for sCD14. The mean sCD14 level was 1854 ± 1744 pg/mL. Microbiological findings confirmed the presence of bacterial infections within 84 ± 4.8 h from enrollment in all 49 positive patients. Thirty-eight patients were considered responders to empirical antibiotic therapy with a decrease of presepsin at the different time points, while an increased level of sCD14 was highlighted in 11 patients. When the test was performed, 45% of the patients showed no signs or symptoms of bacterial infection. At 30 days of follow-up 43 patients survived, and 6 patients died from septic shock. Conclusions: The PATHFAST test highlighted the presence of infection in a very short time (15 minutes), and the presepsin could be considered an early biomarker in patients with cirrhosis. A greater number of patients are necessary to confirm these data
Superinfections in patients treated with teicoplanin as anti SARSCoV2 AGENT
We read with interest the paper by Giacobbe et al. estimating a cumulative risk of developing at least one bloodstream infection (BSI) episode (largely due to Gram-positive pathogens) of almost 50% after 30 days at risk in (2) Similarly, Somers et al. reported an increased risk to develop bacterial superinfections, principally represented by Staphylococcus aureus ventilatory associated pneumonia (VAP), in critically ill patients infected with SARS-CoV-2 and treated with Tocilizumab. (1) We previously described a cohort of intubated patients affected by severe COVID-19pneumonia treated with the best available therapy (BAT), including Tocilizumab and associated with Teicoplanin. (3) This glycopeptide antibiotic was used with a double purpose: as antiviral agent for COVID-19 and as of possible S.aureus superinfection
VISUOMOTOR INTEGRATION SKILLS IN CHILDREN AFFECTED BY OBSTRUCTIVE SLEEP APNEA SYNDROME: A CASE-CONTROL STUDY
Introduction: Sleep related breathing disorders (SRBD) consist of frequent and repetitive episodes of pharyngeal obstruction
during sleep, with consequent intermittent hypoxia, sleep architecture fragmentation, daytime sleepiness and/or behavioural problems
and executive impairment in children. When untreated, SRBD and obstructive sleep apnea syndrome (OSA) mainly, may
impact school performance, cognition, metabolism, and cardiovascular function.
Aim of the present study is assessing the visuomotor integration skills in children affected by OSA.
Materials and methods: 57 subjects affected by mild-to severe OSA, PSG diagnosed according to international diagnostic criteria,
(31 males and 26 females) (mean age 10.8; SD \ub1 2.49) and 83 healthy children (45 males and 38 females) (mean age 9.95; SD
\ub1 1.87; p = 0.725). All subjects underwent assessment of motor coordination skills with Movement-ABC tests and visual-motor integration
ability with Visual Motor Integration (VMI) test.
Results: The subjects with OSA show a worse average performances in all items of Movement ABC (p <0.001) respect of controls.
Specifically, children with OSAS show significantly higher values of total points (p <0.001), manual dexterity (p <0.001), ball
skills (p <0.001) and balance (p <0.001). Accordingly, the average centile in OSA children at the MABC-test is significantly reduced
compared with controls (p <0.001). (Table 1) On the other hand, the VMI test evaluation among children with OSAS shows worst
result in total Visuo-Motor Integration (p <0.001), and in Motor Coordination sub-item (p <0.001) than controls. (Table 1).
Conclusion: Our results also support for children and adolescents the hypothesis that executive functioning deficits might be
linked primarily to the degree of severity nocturnal hypoxemia rather than daytime sleepiness, although several other studies are
needed
Steam reforming on transition-metal carbides from density-functional theory
A screening study of the steam reforming reaction (CH_4 + H_2O -> CO + 3H_2)
on early transition-metal carbides (TMC's) is performed by means of
density-functional theory calculations. The set of considered surfaces includes
the alpha-Mo_2C(100) surfaces, the low-index (111) and (100) surfaces of TiC,
VC, and delta-MoC, and the oxygenated alpha-Mo_2C(100) and TMC(111) surfaces.
It is found that carbides provide a wide spectrum of reactivities towards the
steam reforming reaction, from too reactive via suitable to too inert. The
reactivity is discussed in terms of the electronic structure of the clean
surfaces. Two surfaces, the delta-MoC(100) and the oxygen passivated
alpha-Mo_2C(100) surfaces, are identified as promising steam reforming
catalysts. These findings suggest that carbides provide a playground for
reactivity tuning, comparable to the one for pure metals.Comment: 6 pages, 4 figure
Visual\u2013spatial training efficacy in children affected by migraine without aura: A multicenter study
Routinely in the clinical practice, children affected by migraine without aura (MwA) tend to exhibit severe and persistent difficulties within cognitive processes such as attention, memory, and visual\u2013motor integration (VMI) skills. The aim of this study was to assess the visual\u2013spatial and visual\u2013motor abilities among a sample of children with MwA and the effects of a specific computerized training. The study population was composed of 84 patients affected by MwA (39 girls and 45 boys; mean age: 8.91\ub12.46 years), and they were randomly divided into two groups (group A and group B) comparable for age (P=0.581), gender (P=0.826), socioeconomic status (SES), migraine frequency (P=0.415), and intensity (P=0.323). At baseline (T0), the two groups were comparable for movement assessment battery for children (M-ABC) and VMI performances. After 6 months of treatment (T1), group A showed lower scores in the dexterity item of M-ABC test (P<0.001) and higher scores in M-ABC global performance centile (P<0.001) and total (P<0.001), visual (P=0.017), and motor (P<0.001) tasks of VMI test than group B. Moreover, at T1, group A showed higher scores in total (P<0.001) and motor (P<0.001) tasks of VMI test and in M-ABC global performance centile (P<0.001) and lower scores in the dexterity item of M-ABC test (P<0.001) than at T0. Group B showed, at T1, performances comparable to T0 for all evaluations. As reported by recent studies about alteration MwA among children in motor abilities, our study confirmed these difficulties and the efficacy of a specific software training, suggesting a new rehabilitative proposal in childhood
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