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A highly sensitive fiber temperature sensor based on in-line Mach-Zehnder interferometers (MZIs) and Vernier effect was proposed and experimentally demonstrated. The MZI was fabricated by splicing a section of hollow core fiber between two pieces of multimode fiber. The temperature sensitivity obtained by extracting envelope dip shift of the superimposed spectrum reaches to 528.5 pm/°C in the range of 0 °C–100 °C, which is 17.5 times as high as that without enhanced by the Vernier effect. The experimental sensitivity amplification factor is close to the theoretical predication (18.3 times).The proposed sensitivity enhancement system employs parallel connecting to implement the Vernier effect, which possesses the advantages of easy fabrication and high flexibility.

The expected value of partial perfect information (EVPPI) provides an upper bound on the value of collecting further evidence on a set of inputs to a cost-effectiveness decision model. Standard Monte Carlo (MC) estimation of EVPPI is computationally expensive as it requires nested simulation. Alternatives based on regression approximations to the model have been developed, but are not practicable when the number of uncertain parameters of interest is large and when parameter estimates are highly correlated. The error associated with the regression approximation is difficult to determine, while MC allows the bias and precision to be controlled. In this paper, we explore the potential of Quasi Monte-Carlo (QMC) and Multilevel Monte-Carlo (MLMC) estimation to reduce computational cost of estimating EVPPI by reducing the variance compared with MC, while preserving accuracy. In this paper, we develop methods to apply QMC and MLMC to EVPPI, addressing particular challenges that arise where Markov Chain Monte Carlo (MCMC) has been used to estimate input parameter distributions. We illustrate the methods using a two examples: a simplified decision tree model for treatments for depression, and a complex Markov model for treatments to prevent stroke in atrial fibrillation, both of which use MCMC inputs. We compare the performance of QMC and MLMC with MC and the approximation techniques of Generalised Additive Model regression (GAM), Gaussian process regression (GP), and Integrated Nested Laplace Approximations (INLA-GP). We found QMC and MLMC to offer substantial computational savings when parameter sets are large and correlated, and when the EVPPI is large. We also find GP and INLA-GP to be biased in those situations, while GAM cannot estimate EVPPI for large parameter sets.

To control the quality of different forms of Suanzaoren decoction, an effective and reliable method for the simultaneous determination of 13 major components (neomangiferin, mangiferin, spinosin, liquiritin apioside, liquiritin, 6′′′-feruloylspinosin, senkyunolide I, timosaponin BII, isoliquiritoside, timosaponin C, jujuboside A, jujuboside B, and timosaponin AIII) was developed and validated for the first time in this study using high-performance liquid chromatography with diode array detection and evaporative light scattering detection. The chromatographic separation was performed on a Venusil MP C18 column (250 mm × 4.6 mm, 5 μm) at 30°C with a gradient of acetonitrile/redistilled water as the mobile phase. Diode array detection was carried out at a wavelength of 275 nm. The drift tube temperature and the nitrogen gas flow rate of the evaporative light scattering detection were set at 50°C and 1.6 L/min, respectively. The newly developed method was successfully applied to the determination of 13 components in lab-prepared Suanzaoren oral liquid, Suanzaoren mixture, and clinical Suanzaoren granules, and this study showed that this was a useful way to comprehensively evaluate the quality of Suanzaoren decoction in different forms of the preparation.

Objectives. Determine the optimal, licensed, first-line anticoagulant for prevention of ischemic stroke in patients with non-valvular atrial fibrillation (AF) in England and Wales from the UK National Health Service (NHS) perspective and estimate value to decision making of further research. Methods. We developed a cost-effectiveness model to compare warfarin (international normalized ratio target range 2–3) with directly acting (or non–vitamin K antagonist) oral anticoagulants (DOACs) apixaban 5 mg, dabigatran 150 mg, edoxaban 60 mg, and rivaroxaban 20 mg, over 30 years post treatment initiation. In addition to death, the 17-state Markov model included the events stroke, bleed, myocardial infarction, and intracranial hemorrhage. Input parameters were informed by systematic literature reviews and network meta-analysis. Expected value of perfect information (EVPI) and expected value of partial perfect information (EVPPI) were estimated to provide an upper bound on value of further research. Results. At willingness-to-pay threshold £20,000, all DOACs have positive expected incremental net benefit compared to warfarin, suggesting they are likely cost-effective. Apixaban has highest expected incremental net benefit (£7533), followed by dabigatran (£6365), rivaroxaban (£5279), and edoxaban (£5212). There was considerable uncertainty as to the optimal DOAC, with the probability apixaban has highest net benefit only 60%. Total estimated population EVPI was £17.94 million (17.85 million, 18.03 million), with relative effect between apixaban versus dabigatran making the largest contribution with EVPPI of £7.95 million (7.66 million, 8.24 million). Conclusions. At willingness-to-pay threshold £20,000, all DOACs have higher expected net benefit than warfarin but there is considerable uncertainty between the DOACs. Apixaban had the highest expected net benefit and greatest probability of having highest net benefit, but there is considerable uncertainty between DOACs. A head-to-head apixaban versus dabigatran trial may be of value.

Insomnia, depression, and Alzheimer's disease are all neurodegenerative diseases and are associated with the levels of steroid hormones. To investigate the internal connection and difference of steroid hormones among these three diseases and distinguish them from the perspective of biomarkers, an easy, quick, and efficient high-performance liquid chromatography with tandem mass spectrometry method was established and validated to determine six steroid hormones simultaneously in rat serum. The separation was accomplished on a SHIM-PACK XR-ODS chromatographic column with 0.1% v/v formic acid and methanol as the mobile phase and the detection was performed with electrospray ionization source in the positive ion mode. Based on the concentrations of steroid hormones, all the groups could be distinguished obviously from each other by using partial least square discriminant analysis. Meanwhile, 11-deoxycortisol, corticosterone, and cortisol were identified as potential biomarkers and 100% of samples were classified correctly by Bayes' discriminant function. These biomarkers were further screened by one-way analysis of variance and cortisol was significantly different among all these groups. Bayes' discriminant function was also built by cortisol and the classification accuracy was 87.2%. This workflow including determination of steroid hormones and discrimination among three neurological diseases would provide a basis for further clinical studies.

Epidemiological, cross-sectional, and prospective studies have suggested that insomnia, Alzheimer&rsquo, s disease (AD) and depression are mutually interacting conditions and frequently co-occur. The monoamine and amino acid neurotransmitter systems in central nervous system were involved in the examination of neurobiological processes of this symptom complex. However, few studies have reported systematic and contrastive discussion of different neurotransmitters (NTs) changing in these neurological diseases. Thus, it is necessary to establish a reliable analytical method to monitoring NTs and their metabolite levels in rat brain tissues for elucidating the differences in pathophysiology of these neurological diseases. A rapid, sensitive and reliable LC-MS/MS method was established for simultaneous determination of the NTs and their metabolites, including tryptophan (Trp), tyrosine (Tyr), serotonin (5-HT), 5-hydroxyindolacetic acid (5-HIAA), dopamine (DA), acetylcholine (ACh), norepinephrine (NE), glutamic acid (Glu), and &gamma, aminobutyric acid (GABA) in rat brain tissues. The mobile phase consisting of methanol and 0.01% formic acid in water was performed on an Inertsil EP C18 column, and the developed method was validated well. Results demonstrated that there were significant differences for 5-HT, DA, NE, Trp, Tyr and ACh between model and control group in all three models, and a Bayes linear discriminant function was established to distinguish these three kinds of nervous system diseases by DA, Tyr and ACh for their significant differences among control and three model groups. It could be an excellent strategy to provide perceptions into the similarity and differentia of mechanisms from the point of NTs&rsquo, changing in brain directly and a new method to distinguish insomnia, depression and AD from view of essence.

In this article, we propose a space-time Multi-Index Monte Carlo (MIMC) estimator for a one-dimensional parabolic stochastic partial differential equation (SPDE) of Zakai type. We compare the complexity with the Multilevel Monte Carlo (MLMC) method of Giles and Reisinger (2012), and find, by means of Fourier analysis, that the MIMC method: (i) has suboptimal complexity of $O(\varepsilon^{-2}|\log\varepsilon|^3)$ for a root mean square error (RMSE) $\varepsilon$ if the same spatial discretisation as in the MLMC method is used; (ii) has a better complexity of $O(\varepsilon^{-2}|\log\varepsilon|)$ if a carefully adapted discretisation is used; (iii) has to be adapted for non-smooth functionals. Numerical tests confirm these findings empirically.

The reporting period has shown that Space has become a firmly established domain in observational Astrophysics, also in the low energy astrophysics area. The launching of new spacecraft is always an important addition to the capabilities of the Astronomers, but the availability of space observatories is strongly affected by the fact that they disappear as their subsystems become damaged or, for other reasons, become inoperable. The relatively short life of astronomical space facilities has generated new dynamic in the life cycle of observational tools for the astronomer, rather different from that for ground facilities. Launch failures or the final in-orbit functionality verification can also very strongly affect the availability of observational capabilities in space astrophysics. The only spacecraft designed without this built-in life time restriction, is the Hubble Space Telescope, which can be serviced by the Space Shuttle.

The oldest historical supernova (SN), recorded by ancient Chinese in 14th Century B.C. on pieces of tortoise shells or bones, is identified with the aid of modern space γ-ray observations. Hard X-rays with energy up to 20 keV were observed from IC 443 by the X-ray satellite Ginga. We infer from these observations the age of IC 443 is ∼ 1000 — 1400 yrs. The result supports the hypothesis that IC 443 is the remnant of the historical SN 837 that occurred during the Tang Dynasty. The association between the supernova remnant (SNR) CTB 80 and SN 1408 has been hotly debated for about ten years and is briefly reviewed and discussed here. A new picture is presented to explain this association. High energy emission from historical SNRs can persist in a multiphase interstellar medium (ISM). As a result, the study of the relationship between SNRs and ancient guest stars has gained new vitality.

Recently, many unusual morphologies of supernova remnants (SNRs) have been discovered: semicircular shell; center-brightened but without center point source; two-lobed; bipolar; irregular, etc. To understand these varieties of morphologies, we have made theoretical models. One of the main reasons of their unusualness is the multiphase structure of the interstellar medium (ISM) and circumstellar medium (CSM) where they evolved, and the CSM is connected with their progenitor.

SS433 is a famous exotic object in the center of radio source W50. It has been widely observed at various wavelengths and has attracted more and more attention since 1978. The most unusual feature of SS433 is two relativistic jets ejected at a velocity of 0.26c in opposite directions (MARGON [1]). This feature can explain the simultaneous presence of red and blue shifts of strong optical emission lines varying periodically as well as the two bright X-ray lobes stretched in the direction of the jets (SEWARD et al. [2]). In 1987, six infrared knots around SS433 were discovered from IRAS data by BAND [3]. They have similar infrared spectra except for the fifth one. Band suggested that the fifth one is a different kind of object [3], and we agree. But for the other five knots, we suggest a different model. We don’t think it is accidental that five knots are all located in the direction of the jets and are within, or adhere to, the radio shell of W50. It is very probable that they result from the interaction between the jets and the interstellar medium. We assume that the knots consist mainly of dust grains and gas. Both are continuously heated by collisions of particles in the jets. Their spectra are explained by the thermal radiation of dust grains and the free-free emission of partly ionized hydrogen gases.

The origin and evolution of neutron star magnetic fields has been hotly debated for a long time. Spontaneous field decay was originally proposed with timescales of (5–10) × 106years, while another possible model which associates field decay with mass accretion in the evolution of binary systems has been suggested (see Bhattacharya & van den Heuvel 1991 for a review). The aim of this paper is to examine whether accretion-induced field decay can reproduce the observed properties of the wide binary radio pulsars in quantitative calculations.In a binary system consisting of a neutron star and a low-mass giant companion, if the initial orbital period is longer than 1 day, mass transfer, taking the form of Roche-lobe overflow, is driven by the nuclear evolution of the giant through radius expansion (Webbink et al. 1983). We assume the mass accretion rateṀof the neutron star is limited to the Eddington accretion rateṀE≃ 10−8M⊙yr−1. If the mass transfer rate is in excess ofṀE, the rest mass is blown from the system in the forms of jets or beams.

The radio and X-ray images of the supernova remnant CTB 109 have the morphology of a semicircular shell. It is shown that such a structure is a natural result of a supernova explosion that occurred 3,000 yr ago near an interface between the diffuse interstellar medium and a dense molecular cloud. The calculated X-ray, infrared, and radio fluxes agree fairly well with the observed values.

Supplemental material, Appendices_-_rev1_-_clean.rjf_online_supp for Directly Acting Oral Anticoagulants for the Prevention of Stroke in Atrial Fibrillation in England and Wales: Cost- Effectiveness Model and Value of Information Analysis by Howard H. Z. Thom, Will Hollingworth, Reecha Sofat, Zhenru Wang, Wei Fang, Pritesh N. Bodalia, Peter A. Bryden, Philippa A. Davies, Deborah M. Caldwell, Sofia Dias, Diane Eaton, Julian P. T. Higgins, Aroon D. Hingorani, Jose A. Lopez-Lopez, George N. Okoli, Alison Richards, Chris Salisbury, Jelena Savović, Annya Stephens-Boal, Jonathan A. C. Sterne and Nicky J. Welton in MDM Policy & Practice

Supplemental material, Appendices_-_rev1_-_clean.rjf_online_supp for Directly Acting Oral Anticoagulants for the Prevention of Stroke in Atrial Fibrillation in England and Wales: Cost- Effectiveness Model and Value of Information Analysis by Howard H. Z. Thom, Will Hollingworth, Reecha Sofat, Zhenru Wang, Wei Fang, Pritesh N. Bodalia, Peter A. Bryden, Philippa A. Davies, Deborah M. Caldwell, Sofia Dias, Diane Eaton, Julian P. T. Higgins, Aroon D. Hingorani, Jose A. Lopez-Lopez, George N. Okoli, Alison Richards, Chris Salisbury, Jelena Savović, Annya Stephens-Boal, Jonathan A. C. Sterne and Nicky J. Welton in MDM Policy & Practice