Modelling volatility with mixture density networks

Volatility is an important variable in financial forecasting. Forecasting volatility requires a development of a suitable model for it. In this paper, we examine different time series models for volatility modelling. Specifically, we will study the use of recurrent mixture density networks, GARCH and EGARCH models to model volatility. In addition, we demonstrate the impact of different factors on the accuracy and completeness of each of these models

Factors Affecting Tourists Satisfaction of Jordan as a Tourism Destination

This study aimed to examine the factors affecting tourist’s satisfaction of Jordan as a tourism destination. A Convenience sample of 500 tourists was selected from those who visited different Jordanian places. They asked to answer a set-scale questionnaire that measure tourist expectation and his/her perception toward destination image, emotional involvement, perceived outcome, self image and his satisfaction. Findings of the study indicated that Perceived outcomes, Jordan image and the emotional involvement had a significant impact on the tourists’satisfaction/ dissatisfaction. While self image, and perceived expectations had no influence. Furthermore, findings indicated that tourist’s satisfaction levels do not change according to gender, martial status, and education levels. But with different nationalities, ages, and monthly income the tourists had different level of satisfaction. Finally, many recommendations were recommended as follows: 1- Giving more attention to the Gulf of Aqaba and Dead Sea beaches and work on developing suitable protection and maintenance programs. 2 - Focusing on the development of promotional programs which aim to inform tourist about different festivals in Jordan. Also, spreading the festivals to all seasons of the year. 3- Increasing co-operation between tourism organizations in Jordan and other Arab countries in order to develop a good package of tourism programs at competitive prices. 4- Focusing on exploring new Foreign and Arab markets to attract tourists to visit Jordan

Textile Reinforced Concrete: Design Methodology and Novel Reinforcement

Fibre reinforcement has been used to reinforce concrete members for decades. It has combined well with concrete to help control cracking and increase toughness and other properties such as corrosion resistance. The use of traditional fibre reinforcement has led to the development of a new material called textile reinforcement (multifilament continuous fibre) which can also be used as the main reinforcement instead of steel reinforcement. This study experimentally investigates concrete beams reinforced only with carbon textile material (TRC beams). The tensile strength of textile reinforcement and pull out strength of TRC were measured. Four-point bending tests were performed on 76 beams (small and large scale beams). Several parameters such as volume fraction and reinforcement layout were studied in order to investigate their effect on TRC beam behaviour. The results showed that with the correct layout and geometry of textile reinforcement, these reinforced concrete beams, providing they had sufficient cover thickness, would perform well. Also, the results confirmed that the bond between the concrete and textile reinforcement plays a vital role in TRC beam performance. The behaviour of the TRC beams was compared with that of the steel reinforced concrete (SRC) beams; a major advantage of the TRC beam was the reduced crack widths. This study finishes by proposing a design methodology for TRC beams. Guidance covers flexural design, predictions for moment-curvature, and predictions for crack width of TRC beams

Effect of Grade III Lumbar Mobilization on Back Muscles in Chronic Low Back Pain: A Randomized Controlled Trial

BACKGROUND: Lumbar mobilization is a standard intervention for lower back pain (LBP). However, its effect on the activity of back muscles is not well known. OBJECTIVES: To investigate the effects of lumbar mobilization on the activity/contraction of erector spinae (ES) and lumbar multifidus (LM) muscles in people with LBP. DESIGN: Randomized controlled study. METHODS: 21 subjects with LBP received either grade III central lumbar mobilization or placebo (light touch) intervention on lumbar segment level 4 (L4). Surface electromyography (EMG) signals of ES and ultrasound (US) images of LM were captured before and after the intervention. The contraction of LM was calculated from US images at L4 level. The normalized amplitude of EMG signals (nEMG) and activity onset of ES were calculated from the EMG signals at both L1 and L4 levels. RESULTS: Significant differences were found between the mobilization and placebo groups in LM contraction (p=0.03), nEMG of ES at L1 (p=0.01) and L4 (p=0.05), and activity onset of ES at L1 (p=0.02). CONCLUSION: Lumbar mobilization decreased both the activity amplitude and the activity onset of ES in people with LBP. However, the significant difference in LM contraction was small and may not have clinical significance

Exogenous WNT5A and WNT11 proteins rescue CITED2 dysfunction in mouse embryonic stem cells and zebrafish morphants

Mutations and inadequate methylation profiles of CITED2 are associated with human congenital heart disease (CHD). In mouse, Cited2 is necessary for embryogenesis, particularly for heart development, and its depletion in embryonic stem cells (ESC) impairs cardiac differentiation. We have now determined that Cited2 depletion in ESC affects the expression of transcription factors and cardiopoietic genes involved in early mesoderm and cardiac specification. Interestingly, the supplementation of the secretome prepared from ESC overexpressing CITED2, during the onset of differentiation, rescued the cardiogenic defects of Cited2-depleted ESC. In addition, we demonstrate that the proteins WNT5A and WNT11 held the potential for rescue. We also validated the zebrafish as a model to investigate cited2 function during development. Indeed, the microinjection of morpholinos targeting cited2 transcripts caused developmental defects recapitulating those of mice knockout models, including the increased propensity for cardiac defects and severe death rate. Importantly, the co-injection of anti-cited2 morpholinos with either CITED2 or WNT5A and WNT11 recombinant proteins corrected the developmental defects of Cited2-morphants. This study argues that defects caused by the dysfunction of Cited2 at early stages of development, including heart anomalies, may be remediable by supplementation of exogenous molecules, offering the opportunity to develop novel therapeutic strategies aiming to prevent CHD.Agência financiadora: Fundação para a Ciência e a Tecnologia (FCT) Comissão de Coordenação e Desenvolvimento Regional do Algarve (CCDR Algarve) ALG-01-0145-FEDER-28044; DFG 568/17-2 Algarve Biomedical Center (ABC) Municipio de Louléinfo:eu-repo/semantics/publishedVersio

WR 110: A Single Wolf-Rayet Star With Corotating Interaction Regions In Its Wind?

A 30-day contiguous photometric run with the MOST satellite on the WN5-6b star WR 110 (HD 165688) reveals a fundamental periodicity of P = 4.08 +/- 0.55 days along with a number of harmonics at periods P/n, with n ~ 2,3,4,5 and 6, and a few other possible stray periodicities and/or stochastic variability on timescales longer than about a day. Spectroscopic RV studies fail to reveal any plausible companion with a period in this range. Therefore, we conjecture that the observed light-curve cusps of amplitude ~ 0.01 mag that recur at a 4.08 day timescale may arise in the inner parts, or at the base of, a corotating interaction region (CIR) seen in emission as it rotates around with the star at constant angular velocity. The hard X-ray component seen in WR 110 could then be a result of a high velocity component of the CIR shock interacting with the ambient wind at several stellar radii. Given that most hot, luminous stars showing CIRs have two CIR arms, it is possible that either the fundamental period is 8.2 days or, more likely in the case of WR 110, there is indeed a second weaker CIR arm for P = 4.08 days, that occurs ~ two thirds of a rotation period after the main CIR. If this interpretation is correct, WR 110 therefore joins the ranks with three other single WR stars, all WN, with confirmed CIR rotation periods (WR 1, WR 6, and WR 134), albeit with WR 110 having by far the lowest amplitude photometric modulation. This illustrates the power of being able to secure intense, continuous high-precision photometry from space-based platforms such as MOST. It also opens the door to revealing low-amplitude photometric variations in other WN stars, where previous attempts have failed. If all WN stars have CIRs at some level, this could be important for revealing sources of magnetism or pulsation in addition to rotation periods.Comment: 25 pages, 8 figures, 2 tables, accepted in Ap

Comparison of acoustic voice features derived from mobile devices and studio microphone recordings

Objectives/Hypothesis Improvements in mobile device technology offer new opportunities for remote monitoring of voice for home and clinical assessment. However, there is a need to establish equivalence between features derived from signals recorded from mobile devices and gold standard microphone-preamplifiers. In this study acoustic voice features from android smartphone, tablet, and microphone-preamplifier recordings were compared. Methods Data were recorded from 37 volunteers (20 female) with no history of speech disorder and six volunteers with Huntington's disease (HD) during sustained vowel (SV) phonation, reading passage (RP), and five syllable repetition (SR) tasks. The following features were estimated: fundamental frequency median and standard deviation (F0 and SD F0), harmonics-to-noise ratio (HNR), local jitter, relative average perturbation of jitter (RAP), five-point period perturbation quotient (PPQ5), difference of differences of amplitude and periods (DDA and DDP), shimmer, and amplitude perturbation quotients (APQ3, APQ5, and APQ11). Results Bland-Altman analysis revealed good agreement between microphone and mobile devices for fundamental frequency, jitter, RAP, PPQ5, and DDP during all tasks and a bias for HNR, shimmer and its variants (APQ3, APQ5, APQ11, and DDA). Significant differences were observed between devices for HNR, shimmer, and its variants for all tasks. High correlation was observed between devices for all features, except SD F0 for RP. Similar results were observed in the HD group for SV and SR task. Biological sex had a significant effect on F0 and HNR during all tests, and for jitter, RAP, PPQ5, DDP, and shimmer for RP and SR. No significant effect of age was observed. Conclusions Mobile devices provided good agreement with state of the art, high-quality microphones during structured speech tasks for features derived from frequency components of the audio recordings. Caution should be taken when estimating HNR, shimmer and its variants from recordings made with mobile devices

Outcomes of nonemergent percutaneous coronary intervention requiring mechanical circulatory support in patients without cardiogenic shock

BACKGROUND: The utilization of mechanical circulatory support (MCS) for percutaneous coronary intervention (PCI) using percutaneous ventricular assist device (PVAD) or intra-aortic balloon pump (IABP) has been increasing. We sought to evaluate the outcome of coronary intervention using PVAD compared with IABP in noncardiogenic shock and nonacute myocardial infarction patients. METHOD: Using the National Inpatient Sampling (NIS) database from 2005 to 2014, we identified patients who underwent PCI using ICD 9 codes. Patients with cardiogenic shock, acute coronary syndrome, or acute myocardial infarction were excluded. Patient was stratified based on the MCS used, either to PVAD or IABP. Univariate and multivariate logistic regression were performed to study PCI outcome using PVAD compared with IABP. RESULTS: Out of 21,848 patients who underwent PCI requiring MCS, 17,270 (79.0%) patients received IABP and 4,578 (21%) patients received PVAD. PVAD patients were older (69 vs. 67, p \u3c .001), were less likely to be women (23.3% vs. 33.3%, p \u3c .001), and had higher rates of hypertension, diabetes, hyperlipidemia prior PCI, prior coronary artery bypass graft surgery, anemia, chronic lung disease, liver disease, renal failure, and peripheral vascular disease compared with IABP group (p ≤ .007). Using Multivariate logistic regression, PVAD patients had lower in-hospital mortality (6.1% vs. 8.8%, adjusted odds ratio [aOR] 0.62; 95% CI 0.51, 0.77, p \u3c .001), vascular complications (4.3% vs. 7.5%, aOR 0.78; 95% CI 0.62, 0.99, p = .046), cardiac complications (5.6% vs. 14.5%, aOR 0.29; 95% CI 0.24, 0.36, p \u3c .001), and respiratory complications (3.8% vs. 9.8%, aOR 0.37; 95% CI 0.28, 0.48, p \u3c .001) compared with patients who received IABP. CONCLUSION: Despite higher comorbidities, nonemergent PCI procedures using PVAD were associated with lower mortality compared with IABP