On the accuracy of conservation of adiabatic invariants in slow-fast systems

Let the adiabatic invariant of action variable in slow-fast Hamiltonian system with two degrees of freedom have two limiting values along the trajectories as time tends to infinity. The difference of two limits is exponentially small in analytic systems. An iso-energetic reduction and canonical transformations are applied to transform the slow-fast systems to form of systems depending on slowly varying parameters in a complexified phase space. On the basis of this method an estimate for the accuracy of conservation of adiabatic invariant is given for such systems.Comment: 27 pages, 14 figure

Resistant maltodextrin as a shell material for encapsulation of naringin: Production and physicochemical characterization

YesHerein the potential of a relatively new water soluble fiber, resistant maltodextrin (RMD) to encapsulate grapefruit polyphenol, naringin, using spray drying was evaluated. Full factorial Design Of Experiments (DOE) for spray drying with two levels of fiber–naringin ratio and spray dryer inlet temperature was executed. Resulting powders were characterized with respect to particle size and morphology, crystallinity, thermal properties, moisture sorption and naringin aqueous solubility increase. A 60–80% encapsulation was achieved. Thermal and moisture sorption behaviors of these dispersions were found to be dominated by RMD. By varying fiber–naringin ratio and spray drying temperatures, naringin was able to disperse in amorphous form in RMD matrix, which led to 20–55% increase in aqueous solubility. Solubility enhancement was found to correlate positively with increasing fiber: naringin ratio and spray drying temperature due to multiple factors discussed in this study. In conclusion, fiber–polyphenol bicomponent nutraceutical was successfully developed based on a well-established encapsulation technology i.e. spray-drying

Increased prevalence of ECG markers for sudden cardiac arrest in refractory epilepsy.

BACKGROUND AND AIM: People with epilepsy are at increased risk of sudden cardiac arrest (SCA) due to ECG-confirmed ventricular tachycardia/fibrillation, as seen in a community-based study. We aimed to determine whether ECG-risk markers of SCA are more prevalent in people with epilepsy. METHODS: In a cross-sectional, retrospective study, we analysed the ECG recordings of 185 people with refractory epilepsy and 178 controls without epilepsy. Data on epilepsy characteristics, cardiac comorbidity, and drug use were collected, and general ECG variables (heart rate (HR), PQ and QRS intervals) assessed. We analysed ECGs for three markers of SCA risk: severe QTc prolongation (male >450 ms, female >470 ms), Brugada ECG pattern, and early repolarisation pattern (ERP). Multivariate regression models were used to analyse differences between groups, and to identify associated clinical and epilepsy-related characteristics. RESULTS: People with epilepsy had higher HR (71 vs 62 bpm, p<0.001) and a longer PQ interval (162.8 vs 152.6 ms, p=0.001). Severe QTc prolongation and ERP were more prevalent in people with epilepsy (QTc prolongation: 5% vs 0%; p=0.002; ERP: 34% vs 13%, p<0.001), while the Brugada ECG pattern was equally frequent in both groups (2% vs 1%, p>0.999). After adjustment for covariates, epilepsy remained associated with ERP (ORadj 2.4, 95% CI 1.1 to 5.5) and severe QTc prolongation (ORadj 9.9, 95% CI 1.1 to 1317.7). CONCLUSIONS: ERP and severe QTc prolongation appear to be more prevalent in people with refractory epilepsy. Future studies must determine whether this contributes to increased SCA risk in people with epilepsy

Identifying and appraising patient-reported outcome measures on treatment satisfaction in acne: a systematic review

Background After dermatitis, acne is the next skin disease to contribute most to the burden of skin diseases worldwide. Recently, seven core outcome domains have been identified, which together form an Acne Core Outcome Set (ACORN). One of these was satisfaction with acne treatment.Objectives To identify studies that described the development of patient-reported outcome measures (PROMS), evaluated one or more measurement properties of a PROM, or evaluated the interpretability of a PROM in patients with acne regarding treatment satisfaction.Methods The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) search strategy for identifying PROMS on acne treatment satisfaction was used. We searched PubMed, MEDLINE, Embase, LILACS, Web of Science, Cochrane Library, Emcare, PsycINFO and Academic Search premier (June 2020). Study selection, data extraction and assessment of methodological quality according to COSMIN guidance were carried out independently by two authors.Results Only one study could be included, describing the development of a treatment satisfaction measure in patients with acne. The development was assessed as inadequate and data on measurement properties were lacking. Additionally, we found 188 studies reporting treatment satisfaction solely as an outcome, using a wide variety of methods, none of them standardized or validated.Conclusions We could not find a PROM on treatment satisfaction to recommend for a core outcome set in acne. There is an unmet need for a PROM on treatment satisfaction in acne that is robustly developed, designed and validated.Dermatology-oncolog

Cost-benefit analysis of introducing next-generation sequencing (metagenomic) pathogen testing in the setting of pyrexia of unknown origin

Pyrexia of unknown origin (PUO) is defined as a temperature of >38.3°C that lasts for >3 weeks, where no cause can be found despite appropriate investigation. Existing protocols for the work-up of PUO can be extensive and costly, motivating the application of recent advances in molecular diagnostics to pathogen testing. There have been many reports describing various analytical methods and performance of metagenomic pathogen testing in clinical samples but the economics of it has been less well studied. This study pragmatically evaluates the feasibility of introducing metagenomic testing in this setting by assessing the relative cost of clinically-relevant strategies employing this investigative tool under various cost and performance scenarios using Singapore as a demonstration case, and assessing the price and performance benchmarks, which would need to be achieved for metagenomic testing to be potentially considered financially viable relative to the current diagnostic standard. This study has some important limitations: we examined only impact of introducing the metagenomic test to the overall diagnostic cost and excluded costs associated with hospitalization and makes assumptions about the performance of the routine diagnostic tests, limiting the cost of metagenomic test, and the lack of further work-up after positive pathogen detection by the metagenomic test. However, these assumptions were necessary to keep the model within reasonable limits. In spite of these, the simplified presentation lends itself to the illustration of the key insights of our paper. In general, we find the use of metagenomic testing as second-line investigation is effectively dominated, and that use of metagenomic testing at first-line would typically require higher rates of detection or lower cost than currently available in order to be justifiable purely as a cost-saving measure. We conclude that current conditions do not warrant a widespread rush to deploy metagenomic testing to resolve any and all uncertainty, but rather as a front-line technology that should be used in specific contexts, as a supplement to rather than a replacement for careful clinical judgement

Direct measurement of optical quasidistribution functions: multimode theory and homodyne tests of Bell's inequalities

We develop a multimode theory of direct homodyne measurements of quantum optical quasidistribution functions. We demonstrate that unbalanced homodyning with appropriately shaped auxiliary coherent fields allows one to sample point-by-point different phase space representations of the electromagnetic field. Our analysis includes practical factors that are likely to affect the outcome of a realistic experiment, such as non-unit detection efficiency, imperfect mode matching, and dark counts. We apply the developed theory to discuss feasibility of observing a loophole-free violation of Bell's inequalities by measuring joint two-mode quasidistribution functions under locality conditions by photon counting. We determine the range of parameters of the experimental setup that enable violation of Bell's inequalities for two states exhibiting entanglement in the Fock basis: a one-photon Fock state divided by a 50:50 beam splitter, and a two-mode squeezed vacuum state produced in the process of non-degenerate parametric down-conversion.Comment: 18 pages, 7 figure

Measurements of Atmospheric Antiprotons

We measured atmospheric antiproton spectra in the energy range 0.2 to 3.4 GeV, at sea level and at balloon altitude in the atmospheric depth range 4.5 to 26 g/cm^2. The observed energy spectra, including our previous measurements at mountain altitude, were compared with estimated spectra calculated on various assumptions regarding the energy distribution of antiprotons that interacted with air nuclei.Comment: Accepted for publication in PL