Miracle-dz/UniFAR-FTUs huggingface dataset:
May 09, 2020 Do Norway pout (Trisopterus esmarkii) die from spawning stress? Mortality of Norway pout in relation to growth, maturity and density in the North Sea,

Do Norway pout ( Trisopterus esmarkii ) die from spawning stress? Mortality of Norway pout in relation to growth, sexual maturity, and density in the North Sea, Skagerrak, and Kattegat. – ICES Journal of Marine Science, 69: 197–207. The mortality patterns of Norway pout (NP) are not well understood. It has been suggested that NP undergo heavy spawning mortality, and this paper summarizes and provides new evidence in support of this hypothesis. The very low–absent ﬁshing activity in recent years provides a unique opportunity to analyse the natural life-history traits of cohorts in the NP stock in the North Sea. Based on the ICES trawl survey abundance indices, cohort mortality is found to signiﬁcantly increase with age. We argue that this cannot be explained by selectiveness in the ﬁshery, potential size-speciﬁc migrations out of the area, higher predation pressure on older individuals, or differences in survey catchability by NP age from before to after spawning and that it is higher in the main spawning areas than outside. We found that natural mortality ( M ) is signiﬁcantly correlated with sexual maturity, sex, growth, and intraspeciﬁc stock density . All of this is consistent with a greater mortality occurring mainly from the ﬁrst to the second quarter of the year, i.e. spawning mortality, which is discussed as being a major direct and indirect cause of stock mortality.
GARCH Option Valuation: Theory and Evidence

Black and Scholes assumed stock volatility was a constant and known parameter, but the evidence for stochastically time-varying volatility is overwhelming. Most stochastic volatility models introduce a second stochastic process for variance, driven by shocks that are (negatively) correlated with the return process. But this makes volatility a latent variable and the volatility risk factors cannot be hedged, so they should logically carry risk premia. Estimating the variance equation requires sophisticated econometric methods whose small sample properties may be questioned. Generalized autoregressive conditional heteroskadasticity (GARCH) also offers a specification in which volatility is random, but both volatility and returns are driven by the same shocks, so the variance equation is fitted directly on the observed returns. This article presents a comprehensive review of option valuation under GARCH, covering both theory and empirical estimation. The basic GARCH specification captures time-varying volatility, and the authors review modifications that incorporate known characteristics of real-world return processes, including asymmetric response to up and down shocks, reversion toward a slowly time-varying long-run mean, non-affine and/or non-Gaussian shocks, and return processes subject to multiple shocks, including jumps. GARCH models are typically fitted to series of stock returns, but the authors strongly recommend using both stock returns and option data in model fitting. This helps tie the statistical variance estimates to the markets for variance-dependent securities and exploits information from many additional prices available in the options market. They describe practical suggestions for optimizing and review methods for pricing options under GARCH, including early exercise of American options. The article ends with a series of Appendices giving Matlab code for option pricing under alternative GARCH specifications.
Valuing Loss Firms: What Can Be Learned from Analysts' Forecasts?

Prior research documents an anomalous negative price–earnings relation when a simple earnings capitalization model is estimated for loss-making firms. Collins et al. (1999) suggest that the model is misspecified due to the omission of book value of equity. However, results from previous studies are confusing. We try to enrich prior literature by focusing on analysts' forecasts. In particular, we assess the role of earnings and book value in valuing loss firms using several measures based on the information provided by analysts. We hypothesize that the role of accounting figures depends on whether the loss firm is supported or not by investors. According to this argument, we construct several measures of investor support based on analysts' forecasts, and then test the value relevance of accounting information depending on the degree of support. Our results confirm the usefulness of the notion of ‘investor support’. For those loss firms that are expected to liquidate, we find that the inclusion of book value of equity in the model removes the negative sign on the earnings coefficient. However, for those loss firms that are expected to reverse current losses, we find that the coefficient on earnings remains negative despite the inclusion of book value.
Analysis of possible improvement of the plasma performance in JET due to the inward spatial channelling of fast-ion energy

Effects of the spatial chanelling (SC) of the energy of fusion-produced alpha particles—the spatial transfer of the energy of fast ions by destabilized eigenmodes and delivering this energy to bulk plasma particles (Kolesnichenko et al 2010 Phys. Rev. Lett. 104 075001)—on the plasma performance is studied. Analysis is carried out in the assumption that alpha particles located in the peripheral region of the plasma destabilize multiple fast magnetoacoustic modes (FMM) having global radial structure. The FMM with the frequencies close to cyclotron harmonics of alpha particles are considered. It is found that these FMM can be in resonance with the bulk plasma ions and electrons located in the central region of the plasma, delivering the alpha energy to this region. This improves the overall plasma confinement. In addition, it leads to anomalous ion heating when the ion damping of FMM exceeds the electron one. The damping rates of the considered waves are calculated. It is shown that reasonably small amplitude waves can receive and transfer across the flux surfaces as large power density as that required for spatial channelling of a considerable part of fusion energy. The developed theory of the inward spatial channelling is applied to JET experiments carried out during the deuterium–tritium-experiment campaign (DTE1), where presumably anomalous ion heating and improvement of the plasma confinement took place.
Critical success factors for implementation of risk assessment and management practices within the Tanzanian construction industry

Purpose – Despite the extensive research on critical success factors (CSFs), there is a paucity of studies that examine CSFs for the deployment of risk assessment and management processes in developing countries, particularly, Africa. The purpose of this paper is to investigate the perception of construction professionals on CSFs appertaining to the deployment of risk assessment and management practices (RAMP) in Tanzania with the aim of filling the knowledge gap. Design/methodology/approach – The primary data were collected from 67 construction professionals working with clients (private and public), consultants, and contractor organisations (foreign and local) within the Tanzanian construction. Response data was subjected to descriptive and inferential statistics with one-way analysis of variance to examine the differences in the perception of the identified CSFs. Findings – The descriptive and empirical analysis demonstrated a disparity of the ranking of the ten CSFs among the groups; however, the diff.
Racial differences in the association of education with physical and cognitive function in older blacks and whites.

OBJECTIVES Few studies have explicitly tested whether the health disadvantage among older blacks is consistent across the entire range of education. We examined racial differences in the cross-sectional association of education with physical and cognitive function performance in older adults. METHODS Participants included over 9500 blacks and whites, aged ≥ 65 years, from the Chicago Health and Aging Project {64% black, 60% women, mean age = 73.0 (standard deviation [SD] = 6.9), mean education = 12.2 (SD = 3.5)}. Physical function was assessed using 3 physical performance tests, and cognitive function was assessed with 4 performance-based tests; composite measures were created and used in analyses. RESULTS In multiple regression models that controlled for age, age-squared, sex, and race, and their interactions, whites and those with higher education (>12 years) performed significantly better on both functional health measures. The association of education with each indicator of functional health was similar in older blacks and whites with low levels (≤ 12 years) of education. However, at higher levels of education, there was a significantly more positive association between years of education and these functional health outcomes among blacks than whites. DISCUSSION Results from this biracial population-based sample in the Midwest suggest that blacks may enjoy greater returns in functional health for additional education beyond high school.
Heavy Rainfalls Associated with Frontal Depression in Asian Subtropical Humid Region

On June 27, 1972, torrential rains fell over the southwestern Kyushu, the western part of Japan, when a weak frontal depression passed to the north of Kyushu. The large-scale characteristics of heavy rainfalls in the Asian subtropical-humid region are represented through the case study on this heavy rainfall. Synoptic and subsynoptic-scale analyses indicate that 1) the heavy rainfalls occurred within the subtropical air mass to the south of the subtropical jet stream's axis; 2) destabilization of the stratification on the heavy rainfall area was not caused by the cold air intrusion aloft but mainly by the intrusion of the tropical air mass in the lower layer;3) the extremely moist tropical air mass was transported toward the depression from the south along the western periphery of the Pacific subtropical anticyclone. We also give our attention on the differences between the large-scale features of the heavy rainfalls in the Asian subtropical-humid region and these of severe storms in the subtropical-humid region of U.S.A. In essence, the heavy rainfalls are the convective phenomena within the subtropical air mass occurred under the condition of the intrusion of tropical air, while the severe storms are those within the subtropical air mass occurred under the condition of strong cold advection aloft.
Cost-effectiveness of physical activity in the management of COPD patients in the UK

Background: While the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines advise exercise to reduce disease progression, little investment in promoting physical activity (PA) is made by health care authorities. The purpose of this study was to estimate the cost-effectiveness of regular PA vs sedentary lifestyle in people with COPD in the UK. Methods: Efficacy, quality of life, and economic evidence on the PA effects in COPD patients were retrieved from literature to serve as input for a Markov microsimulation model comparing a COPD population performing PA vs a COPD population with sedentary lifestyle. The GOLD classification defined the model health states. For the base case, the cost of PA was estimated at zero, a lifetime horizon was used, and costs and effects were discounted at 3.5%. Analyses were performed from the UK National Health Service (NHS) perspective. Uncertainty around inputs and assumptions were explored via scenario and sensitivity analyses, including a cost threshold analysis. Outcomes were cost/quality-adjusted life year (QALY) gained and cost/year gained. Results: Based on our model, the effects of PA in the UK COPD population would be lower mortality ( - 6%), fewer hospitalizations ( - 2%), gains in years ( + 0.82) and QALYs ( + 0.66), and total cost savings of £2,568. The cost/QALY and cost/year gained were dominant. PA was cost-saving at costs , £35/month and cost-effective at cost , £202/month. The main model drivers were age and PA impact on death and hospital-treated exacerbations. Conclusion: Including PA in the management of COPD leads to long-term clinical benefits. If the NHS promotes only exercise via medical advice, this would lead to health care cost savings. If the NHS chose to fund PA, it would still likely be cost-effective.
Bayesian estimation of the generalized lognormal distribution using objective priors

ABSTRACT The generalized lognormal distribution plays an important role in analysing data from different life testing experiments. In this paper, we consider Bayesian analysis of this distribution using various objective priors for the model parameters. Specifically, we derive expressions for the Jeffreys-type priors, the reference priors with different group orderings of the parameters, and the first-order matching priors. We also study the properties of the posterior distributions of the parameters under these improper priors. It is shown that only two of them result in proper posterior distributions. Numerical simulation studies are conducted to compare the performances of the Bayesian estimators under the considered priors and the maximum likelihood estimates. Finally, a real-data application is also provided for illustrative purposes.
INSTABILITIES IN A SHOCK INTERACTION WITH A PERTURBED CURTAIN OF PARTICLES

We present a two-dimensional computational study of a shock interaction with a particle-seeded curtain where particles initially comprise 4% by volume, and the rest is air. If the initial depth of the curtain in the streamwise direction is variable, numerical results predict vortex formation in both the gas phase and the dispersed phase after the shock-curtain interaction. The phenomenon is distinct from baroclinic (Richtmyer–Meshkov) instability observed on gaseous density interfaces and is caused by the changes in the particle phase number density distribution and related interphase velocity changes.
Molecular Detection of Methicillin Resistant Staphylococcus Aureus Isolated From Hospital Patients and Food Handlers in FCT , North Central , Nigeria

Antimicrobial susceptibility profile and molecular detection of methicillin resistant genes isolated from hospital patients and food handlers in Abuja, Nigeria was evaluated. Specimen collection, identification, isolation and characterization were done following standard microbiological procedures. Polymerase chain reaction (PCR) was employed for the detection of the mecA gene associated with methicillin resistance and other virulent marker genes associated with pathogenicity of S. aureus such as Panton-Valentine Leukocidin (PVL), BlaZ and Nuc genes. The result showed a 27.34% prevalence rate of S. aureus isolates in Abuja metropolis; 38.02% prevalence rate was observed in clinical samples while food handlers had 16.67%. Isolates from hospital patients were more resistant to the antibiotics tested than those from the food handlers. Vancomycin was the most effective antibiotic for MRSA isolates from both clinical patients and food handlers while linezolid could be used as an alternative. This study also observed that all the MRSA isolates were resistant to more than three antibiotics (multidrug resistant). High percentage of the isolates (83.33%) that had cefoxitin MIC of ≥ 6μg/ml encoded mecA gene. Nuc gene was observed in 45.83% of the isolates; 4.17% encoded PVL gene while none of the isolates harbored the blaZ gene. The finds from this study showed a high prevalence of methicillin-resistance S. aureus from clinical patients and food handlers sampled and these sources could serve as source of MRSA dissemination in the community.
Accurate unfolding of photon spectra of clinical linear accelerators using transmission measurements

Most cancer radiation therapy treatments use external photon beams from clinical linear accelerators. For these beams, transmission analysis is a potentially viable approach for independent determination of the photon spectra and the incident electron energies. This study presents a comprehensive physics-based approach to transmission analysis to address the computational and experimental limitations of previous studies. On the computational side, energy differentiation is significantly improved by using transmission data from an optimum combination of multiple attenuators and detectors. Detector energy response, photonuclear attenuation, and corrections for non-ideal exponential attenuation are accounted for and found to have a major effect on the unfolding accuracy. For robust unfolding, the spectra are specified using a new, validated functional form with four free parameters, one of which is the incident electron energy. On the experimental side, the validation is performed on a research linac whose photon spectra and electron beam parameters are directly and independently known. The validation includes eight beams from 10 to 30 MV, with thick bremsstrahlung targets of Be, Al, and Pb. The approach is demonstrated on a clinical linac for 6, 10 and 25 MV beams. A protocol is developed to account for many experimental influence quantities, allowing for measurement accuracy of 0.4% on the smallest signals. The unfolded spectra agree with the benchmark spectra with root-mean-square energy fluence deviations of 4.5%. The accuracy of unfolding the incident electron energy is shown to be 3%. The overall accuracy improvement over the best previous studies is at least a factor of 3. Photon cross section uncertainties are the ultimate limiting factor of the technique. An upper bound estimate at the 95% confidence level for these uncertainties is found to be 0.7%, which is more realistic than the currently used ‘envelope of uncertainty’ of 1 – 2%. By-products of this study include benchmarking the EGSnrc Monte Carlo system for relative ion chamber response calculations at the 0.2% level, and upgrading EGSnrc to model photonuclear attenuation.
Fluid-Structure Interactions: Cross-Flow-Induced Instabilities

1. Introduction 2. Prisms in cross-flow - galloping 3. Vortex-induced vibration and lock-in 4. Wake-induced instabilities of pairs and small groups of cylinders 5. Fluidelastic instabilities in cylinder arrays 6. Ovalling instabilities of shells in cross-flow 7. Rain and wind induced vibrations.
The Rise and Fall of the Widely Held Firm - A History of Corporate Ownership in Canada

A panel of corporate ownership data, stretching back to 1902, shows that the Canadian corporate sector began the century with a predominance of large pyramidal corporate groups controlled by wealthy families or individuals. By mid-century, widely held firms predominated. But, from the 1970s on, pyramidal groups controlled by wealthy families and individuals resurge, restoring a situation similar to that a century earlier. Institutional factors underlying this resurgence are shown to have antecedents deep in the country's colonial past.
Bubble Dynamics and Heat Transfer During Pool Boiling on Wettability Patterned Surfaces

ABSTRACT Surfaces with spatial wettability patterns have been proven to enhance heat transfer coefficient and critical heat flux in pool boiling. To understand the physical mechanism behind this phenomenon and obtain the correlation among some critical parameters (bubble departure frequency, bubble size, nucleation site density, surface tension), pool boiling experiments were conducted. A Pyrex glass with a layer of indium-tin-oxide was used as the substrate. Hydrophobic patterns will serve as nucleation sites. Experiments were conducted in deionized water under atmospheric pressure at a relatively low heat flux. The processes of nucleation, growth, and departure of individual bubbles were visualized by using a high speed camera through the bottom of the heater surface. It has been found that the patterned surface performed the best in heat transfer for subcooled pool boiling when compared with hydrophilic and hydrophobic surfaces. The nucleation site density of the biphilic surface was much higher, when compared with that of the homogeneous surface. The individual bubbles always nucleate on the edge of the hydrophobic and hydrophilic area, and then move onto the hydrophobic pattern. Most of the individual bubbles detach from the wettability patterned surface in the diameter range from 300 µm to 450 µm (around 77.3%). The bubble departure periods scatter in the range from 80 ms to 1500 ms.
The Declining Equity Premium : What Role Does Macroeconomic Risk Play ? ∗

Aggregate stock prices, relative to virtually any indicator of fundamental value, soared to unprecedented levels in the 1990s. Even today, after the market declines since 2000, they remain well above historical norms. Why? We consider one particular explanation: a fall in macroeconomic risk, or the volatility of the aggregate economy. We estimate a two-state regime switching model for the volatility and mean of consumption growth, and find evidence of a shift to substantially lower consumption volatility at the beginning of the 1990s. We then show that there is a strong and statistically robust correlation between low macroeconomic volatility and high asset prices: the estimated posterior probability of being in a low volatility state explains 30 to 60 percent of the post-war variation in the log price-dividend ratio, depending on the measure of consumption analyzed. Next, we study a rational asset pricing model with regime switches in both the mean and standard deviation of consumption growth, where the probabilities of a regime change are calibrated to match estimates from post-war data. Plausible parameterizations of the model are found to account for a significant fraction of the run-up in asset valuation ratios observed in the late 1990s. JEL: G12
Subpixel Linearity Improvement for Intel® RealSense™ Depth Camera D400 Series

In this paper we explore how to improve the subpixel linearity of Intel RealSense Depth Camera D400 series. We will introduce a new “Advanced Depth Parameter” that we call the A-factor, that can be used to tune and improve the subpixel linearity by a factor of 3-5x, i.e. linearity of depth measurements between discrete disparities. To explain this, we digress briefly to the fundamentals underpinning the calculation of depth from stereo. Stereo depth cameras consist of two fixed cameras pointing in the same direction, but separated by a certain distance, called the baseline. The left and right images captured by these cameras are compared on a per-frame basis in order to determine which parts of simultaneously captured images match up. This is also known as solving the correspondence problem. Objects that are close will experience a larger shift, along the axis defined by the two imagers, than objects that are far away. This means that every pixel in the right image would need to be shifted by a different amount to match the proper left image pixel, depending on its distance away, or range. The local shifts are quantified as a number of pixels shifted and is known as the disparity. Finally, through triangulation it is possible to relate the disparity shift of every pixel to the range to every point in the image.