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Cooper and Nyborg (2008) derive a tax-adjusted discount rate formula under a constant proportion leverage policy, investor taxes and risky debt. However, their analysis assumes zero recovery in default. We extend their framework to allow for positive recovery rates. We also allow for differences in bankruptcy codes with respect to the order of priority of interest payments versus repayment of principal in default, which may have tax consequences. The general formula we derive differs from that of Cooper and Nyborg when recovery rates in default are anticipated to be positive. However, under continuous rebalancing, the formula collapses to that of Cooper and Nyborg. We provide an explanation for why the effect of the anticipated recovery rate is not directly visible in the general continuous rebalancing formula, even though this formula is derived under the assumption of partial default. The errors from using the continuous approximation formula are sensitive to the anticipated recovery in default, yet small. The 'cost of debt' in the tax adjusted discount rate formula is the debt's yield rather than its expected rate of return. [ABSTRACT FROM AUTHOR]

Biomass burning for domestic heating has increased in many countries with cold climates in recent years. This paper presents and compares two ways of estimating the contribution of particulate matter (PM2.5) to ambient air from local domestic wood burning, using daily stationary parallel PM2.5 measurements in a wood-burning area and at a reference location. In the first method (based on air mass back trajectories), daily gravimetric PM2.5 mass differences were compared between the two stations for days with low contributions from regional sources. In the second method, 28 filters from each location were chemically analysed, and source contributions were calculated using positive matrix factorisation (PMF). The trajectory method estimated the extra local contribution from domestic wood burning in the woodburning area to be 0.7-1.1 μg m-3, while the PMF method gave a contribution of 0.64 μg m-3. With the PMF method, the total contribution to ambient air from local domestic wood burning was estimated to be 25% of the total PM2.5 mass. The estimated mass contribution using the trajectory method gave a result similar to that of the PMF method, and the method can therefore be a time- and cost-effective first step, especially when no chemical analysis is possible. [ABSTRACT FROM AUTHOR]

Exposure to outdoor air pollutants poses a risk for both non-carcinogenic and carcinogenic respiratory disease outcomes. A standardized health risk assessment (US EPA) utilizes air quality data, body mass and breathing rates to determine potential risk. This health risk assessment study assesses the hazard quotient (HQ) for total PM2.5 and trace elemental constituents (Br, Cl, K, Ni, S, Si, Ti and U) exposure in Pretoria, South Africa. The World Health Organization (WHO) air quality guideline (5 µg m−3) and the yearly South African National Ambient Air Quality Standard (NAAQS) (20 µg m−3) were the references dosages for total PM2.5. A total of 350 days was sampled in Pretoria, South Africa. The mean total PM2.5 concentration during the 34-month study period was 23.2 µg m−3 (0.7–139 µg m−3). The HQ for total PM2.5 was 1.17, 3.47 and 3.78 for adults, children and infants. Non-carcinogenic risks for trace elements K, Cl, S and Si were above 1 for adults. Seasonally, Si was the highest during autumn for adults (1.9) and during spring for S (5.5). The HQ values for K and Cl were highest during winter. The exposure to Ni posed a risk for cancer throughout the year and for As during winters. [ABSTRACT FROM AUTHOR]

The nucleation of twins at grain boundaries was studied in an Mg–3wt.% Al–1wt.% Zn alloy processed by equal channel angular pressing at 200°C. A larger fraction of twin boundaries was observed in comparison to the as-rolled Mg–3wt.% Al–1wt.% Zn alloy. The preferential sites for the twin nucleation were grain boundaries with misorientation angles ranging from 10° to 35°. Growth of the twins into the grain interior was hindered. [ABSTRACT FROM AUTHOR]

It is demonstrated that metalworking processes performed at different temperatures can lead to the [image omitted]- [image omitted] double twinning. This twinning mode has been observed during direct extrusion of the coarse-grained Mg-0.3at.%Al alloy at 433 K and analysed in detail on room-temperature rolled magnesium single crystal with the c-axis parallel to transverse direction and the a-axis parallel to rolling direction. The [image omitted]- [image omitted] double twins originated during initial stage of the formation on coarse-grained and single-crystalline structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • We study which models are suitable for forecasting Bitcoin volatility. • We consider many GARCH and two heterogeneous autoregressive (HAR) models. • Realized variance estimated is used as a proxy for true volatility. • EGARCH and APARCH perform best among the GARCH models. • HAR models perform better than GARCH models. Since Bitcoin price is highly volatile, forecasting its volatility is crucial for many applications, such as risk management or hedging. We study which model is the most suitable for forecasting Bitcoin volatility. We consider several GARCH and two heterogeneous autoregressive (HAR) models and compare them. Since we utilize realized variance estimated from high frequency data as a proxy for true volatility, we can draw sharper conclusions than studies which use only daily data. We find that EGARCH and APARCH perform best among the GARCH models. HAR models based on realized variance perform better than GARCH models based on daily data. Superiority of HAR models over GARCH models is strongest for short-term volatility forecasts. [ABSTRACT FROM AUTHOR]

Personal exposure to PM2.5 and PM1, together with indoor and residential outdoor levels, was measured in the general adult population (30 subjects, 23–51 years of age) of Gothenburg, Sweden. Simultaneously, urban background concentrations of PM2.5 were monitored with an EPA WINS impactor. The 24-h samples were gravimetrically analyzed for mass concentration and black smoke (BS) using a smokestain reflectometer. Median levels of PM2.5 were 8.4 μg/m3 (personal), 8.6 μg/m3 (indoor), 6.4 μg/m3 (residential outdoor), and 5.6 μg/m3 (urban background). Personal exposure to PM1 was 5.4 μg/m3, while PM1 indoor and outdoor levels were 6.2 and 5.2 μg/m3, respectively. In non-smokers, personal exposure to PM2.5 was significantly higher than were residential outdoor levels. BS absorption coefficients were fairly similar for all microenvironments (0.4–0.5 10−5 m−1). Personal exposure to particulate matter (PM) and BS was well correlated with indoor levels, and there was an acceptable agreement between personal exposure and urban background concentrations for PM2.5 and BS2.5 (rs=0.61 and 0.65, respectively). PM1 made up a considerable amount (70–80%) of PM2.5 in all microenvironments. Levels of BS were higher outdoors than indoors and higher during the fall compared with spring. The correlations between particle mass and BS for both PM2.5 vs. BS2.5 and PM1 versus BS1 were weak for all microenvironments including personal exposure. The urban background station provided a good estimate of residential outdoor levels of PM2.5 and BS2.5 within the city (rs=0.90 and 0.77, respectively). Outdoor levels were considerably affected by long-range transported air pollution, which was not found for personal exposure or indoor levels. The within-individual (day-to-day) variability dominated for personal exposure to both PM2.5 and BS2.5 in non-smokers.Journal of Exposure Science and Environmental Epidemiology (2007) 17, 613–624; doi:10.1038/sj.jes.7500562; published online 18 April 2007 [ABSTRACT FROM AUTHOR]

Abstract: Personal exposures as well as indoor and outdoor levels of PM2.5 were measured with cyclones and impactors simultaneously in the winter of 2003 in a residential area where wood burning for domestic space heating is common. Twenty-four-hour samples from both wood-burning households (“wood burners”) and a reference group were analysed for mass and elemental concentration using energy dispersive X-ray fluorescence (EDXRF) and for black smoke (BS) concentration using an EEL 43 reflectometer. Wood-smoke particles made statistically significant contributions of K, Ca, and Zn for both personal exposure and indoor concentration, the median levels of these elements being 66–80% higher for the wood-burning group. In addition, Cl, Mn, Cu, Rb, and Pb were found to be possible markers of wood smoke, though levels of these were only significantly higher among the wood-burning group for either personal exposure or indoor concentrations. PM2.5 mass and S levels were not significantly elevated in wood burners, probably due to large variations in outdoor concentrations from long-distance transported air pollution. Personal exposure and indoor levels showed high correlations for all species, and the personal exposure levels were usually higher than or equal to the indoor levels. The associations between personal exposure and outdoor levels were generally weak except for outdoor S and PM2.5 levels that were both highly correlated with personal S exposure levels . [Copyright &y& Elsevier]

• We model stock price variation around the world during the corona crash. • We use Google search volume activity as a gauge of panic and fear. • Search terms are specific to the coronavirus crisis. • Our sample covers 10 stock market indices. • Excess search volume predicts price variation during the corona crash. Since the outbreak of the COVID-19 pandemic, stock markets around the world have experienced unprecedented declines amid high uncertainty. In this paper, we use Google search volume activity as a gauge of panic and fear. The chosen search terms are specific to the coronavirus crisis and correspond to phrases related to nonpharmaceutical intervention policies to fight physical contagion. We show that during this period, fear of the coronavirus – manifested as excess search volume – represents a timely and valuable data source for forecasting stock price variation around the world. [ABSTRACT FROM AUTHOR]

Stock market returns are difficult to predict, but crisis periods tend to be an exception to this rule. We document that, during the event period from November 2019 to May 2020 with the S&P 500 market index, the corona crash was not an exception. We use a nonlinear autoregressive model, where the autoregressive coefficient is governed by i) abnormal Google searches related to COVID-19 and ii) realized volatility. We find that the autoregressive coefficient was negative over the whole event period, but as market uncertainty and attention to virus increased, the magnitude of the autoregressive coefficient increased as well. [ABSTRACT FROM AUTHOR]

Background: Despite accumulating evidence of an association between air pollution and renal disease, studies on the association between long-term exposure to air pollution and renal function are still contradictory. This study aimed to investigate this association in a large population with relatively low exposure and with improved estimation of renal function as well as renal injury biomarkers. Methods: We performed a cross-sectional analysis in the middle-aged general population participating in the Swedish CardioPulmonary bioImaging Study (SCAPIS; n = 30 154). Individual 10-year exposure to total and locally emitted fine particulate matter (PM2.5), inhalable particulate matter (PM10), and nitrogen oxides (NOx) were modelled using high-resolution dispersion models. Linear regression models were used to estimate associations between exposures and estimated glomerular filtration rate (eGFR, combined creatinine and cystatin C) and serum levels of renal injury biomarkers (KIM-1, MCP-1, IL-6, IL-18, MMP-2, MMP-7, MMP-9, FGF-23, and uric acid), with consideration of potential confounders. Results: Median long-term PM2.5 exposure was 6.2 µg/m3. Almost all participants had a normal renal function and median eGFR was 99.2 mL/min/1.73 m2. PM2.5 exposure was associated with 1.3% (95% CI 0.6, 2.0) higher eGFR per 2.03 µg/m3 (interquartile range, IQR). PM2.5 exposure was also associated with elevated serum matrix metalloproteinase 2 (MMP-2) concentration, with 7.2% (95% CI 1.9, 12.8) higher MMP-2 per 2.03 µg/m3. There was a tendency towards an association between PM10 and higher levels of uric acid, but no associations were found with the other biomarkers. Associations with other air pollutants were null or inconsistent. Conclusion: In this large general population sample at low exposure levels, we found a surprising association between PM2.5 exposure and a higher renal filtration. It seems unlikely that particle function would improve renal function. However, increased filtration is an early sign of renal injury and may be related to the relatively healthy population at comparatively low exposure levels. Furthermore, PM2.5 exposure was associated with higher serum concentrations of MMP-2, an early indicator of renal and cardiovascular pathology. [ABSTRACT FROM AUTHOR]

Since higher risk should be rewarded with higher expected returns, more risky time periods are expected to predict rising stock markets. This paper focuses on implied volatility as a measure of financial risk and economic policy uncertainty (EPU) which includes also regulatory risk. We analyze twelve stock markets for which EPU indices exist and find that even though there is no concurrent relationship between EPU and market movements, high EPU indeed predicts subsequent stock market growth. On the other hand, implied volatility is high when markets are falling but is less informative about future market movements. The economic significance of our results is illustrated by a highly profitable trading strategy, which yields abnormal returns of 15% per year on average across countries. [ABSTRACT FROM AUTHOR]

Background and aims Long-term exposure to air pollution increases cardiopulmonary morbidity and mortality, but it is not clear which components of air pollution are the most harmful, nor which time window of exposure is most relevant. Further studies at low exposure levels have also been called for. We analyzed two Swedish cohorts to investigate the effects of total and source-specific particulate matter (PM) on incident cardiovascular disease for different time windows of exposure. Methods Two cohorts initially recruited to study predictors of cardiovascular disease (the PPS cohort and the GOT-MONICA cohort) were followed from 1990 to 2011. We collected data on residential addresses and assigned each individual yearly total and source-specific PM and Nitrogen Oxides (NO x ) exposures based on dispersion models. Using multivariable Cox regression models with time-dependent exposure, we studied the association between three different time windows (lag 0, lag 1–5, and exposure at study start) of residential PM and NO x exposure, and incidence of ischemic heart disease, stroke, heart failure and atrial fibrillation. Results and discussion During the study period, there were 2266 new-onset cases of ischemic heart disease, 1391 of stroke, 925 of heart failure and 1712 of atrial fibrillation. The majority of cases were in the PPS cohort, where participants were older. Exposure levels during the study period were moderate (median: 13 µg/m 3 for PM 10 and 9 µg/m 3 for PM 2.5 ), and similar in both cohorts. Road traffic and residential heating were the largest local sources of PM air pollution, and long distance transportation the largest PM source in total. In the PPS cohort, there were positive associations between PM in the last five years and both ischemic heart disease (HR: 1.24 [95% CI: 0.98–1.59] per 10 µg/m 3 of PM 10 , and HR: 1.38 [95% CI: 1.08–1.77] per 5 µg/m 3 of PM 2.5 ) and heart failure. In the GOT-MONICA cohort, there were positive but generally non-significant associations between PM and stroke (HR: 1.48 [95% CI: 0.88–2.49] per 10 µg/m 3 of PM 10 , and HR: 1.50 [95% CI: 0.90–2.51] per 5 µg/m 3 of PM 2.5 , in the last five years). Effect estimates were stronger for women, non-smokers, and higher socioeconomic classes. Exposure in the last five years seemed to be more strongly associated with outcomes than other exposure time windows. Associations between source-specific PM air pollution and outcomes were mixed and generally weak. High correlations between the main pollutants limited the use of multi-pollutant models. Conclusions The main PM air pollutants were associated with ischemic heart disease and stroke (in women) at the relatively low exposure levels in Gothenburg, Sweden. The associations tended to be stronger for women than for men, for non-smokers than for smokers, and for higher socioeconomic classes than for lower. The associations could not be attributed to a specific PM source or type, and differed somewhat between the two cohorts. The results of this study confirm that further efforts to reduce air pollution exposure should be undertaken in Sweden to reduce the negative health effects in the general population. [ABSTRACT FROM AUTHOR]

Using data from 214 hydropower projects in Norway we study whether investors in renewable energy projects exert discretion about the timing of investment decisions. We know from interviews with these investors that they do not use the real options model; however, we would like to learn whether they act consistently with this approach. These investments were expected to be supported financially through renewable policy schemes, but were not during the time period we consider. We calculate subsidies implied by investors' decisions using both real options and net present value models and compare these expected subsidies with subsidies observed in a very closely related market (Sweden). Our analysis indicates that our assumed real options model implies expected subsidies that align well with the ones observed. If we assume investors used a net present value model, the corresponding implied subsidies are close to zero. However, we know from interviews with investors that they did expect subsidies. We therefore conclude that the real options model is a meaningful descriptor of the observed investment behavior. [ABSTRACT FROM AUTHOR]

Despite firm evidence for an association between long-term ambient air pollution exposure and cardiovascular morbidity and mortality, results from epidemiological studies on the association between air pollution exposure and atherosclerosis have not been consistent. We investigated associations between long-term low-level air pollution exposure and coronary atherosclerosis. We performed a cross-sectional analysis in the large Swedish CArdioPulmonary bioImaging Study (SCAPIS, n = 30 154), a random general population sample. Concentrations of total and locally emitted particulate matter <2.5 μm (PM 2.5), <10 μm (PM 10), and nitrogen oxides (NO x) at the residential address were modelled using high-resolution dispersion models. We estimated associations between air pollution exposures and segment involvement score (SIS), coronary artery calcification score (CACS), number of non-calcified plaques (NCP), and number of significant stenoses, using ordinal regression models extensively adjusted for potential confounders. Median 10-year average PM 2.5 exposure was 6.2 μg/m3 (range 3.5–13.4 μg/m3). 51 % of participants were women and 51 % were never-smokers. None of the assessed pollutants were associated with a higher SIS or CACS. Exposure to PM 2.5 was associated with NCP (adjusted OR 1.34, 95 % CI 1.13, 1.58, per 2.05 μg/m3). Associations with significant stenoses were inconsistent. In this large, middle-aged general population sample with low exposure levels, air pollution was not associated with measures of total burden of coronary atherosclerosis. However, PM 2.5 appeared to be associated with a higher prevalence of non-calcified plaques. The results suggest that increased risk of early-stage atherosclerosis or rupture, but not increased total atherosclerotic burden, may be a pathway for long-term air pollution effects on cardiovascular disease. [Display omitted] • Firm evidence shows that air pollution is a risk factor for cardiovascular disease. • However, studies of the association with atherosclerosis remain inconclusive. • We assessed air pollution and atherosclerosis in a large Swedish multi-city study. • Air pollution was associated with non-calcified plaques but not total plaque burden. • Our results may indicate an association with early or vulnerable atherosclerosis. [ABSTRACT FROM AUTHOR]

Long-term exposure to air pollution is associated with cardiovascular events. A main suggested mechanism is that air pollution accelerates the progression of atherosclerosis, yet current evidence is inconsistent regarding the association between air pollution and coronary artery and carotid artery atherosclerosis, which are well-established causes of myocardial infarction and stroke. We studied associations between low levels of long-term air pollution, coronary artery calcium (CAC) score, and the prevalence and area of carotid artery plaques, in a middle-aged population-based cohort. The Swedish CArdioPulmonary bioImage Study (SCAPIS) Gothenburg cohort was recruited during 2013–2017 and thoroughly examined for cardiovascular risk factors, including computed tomography of the heart and ultrasonography of the carotid arteries. In 5070 participants (age 50–64 years), yearly residential exposures to air pollution (PM 2.5 , PM 10 , PM coarse , NO x , and exhaust-specific PM 2.5 1990–2015) were estimated using high-resolution dispersion models. We used Poisson regression to examine associations between long-term (26 years' mean) exposure to air pollutants and CAC score, and prevalence of carotid artery plaques, adjusted for potential confounders. Among participants with carotid artery plaques, we also examined the association with plaque area using linear regression. Mean exposure to PM 2.5 was low by international standards (8.5 μg/m3). There were no consistent associations between long-term total PM 2.5 exposure and CAC score or presence of carotid artery plaques, but an association between total PM 2.5 and larger plaque area in participants with carotid plaques. Associations with traffic-related air pollutants were consistently positive for both a high CAC score and bilateral carotid artery plaques. These associations were independent of road traffic noise. We found stronger associations among men and participants with cardiovascular risk factors. The results lend some support to atherosclerosis as a main modifiable pathway between low levels of traffic-related ambient air pollution and cardiovascular disease, especially in vulnerable individuals. • Long-term PM 2.5 was not associated with coronary calcification or carotid plaques. • Traffic-related air pollutants were consistently associated with atherosclerosis. • Associations were stronger in men and in participants with some risk factors. • There was no indication of confounding by road traffic noise. [ABSTRACT FROM AUTHOR]

Air pollution is associated with cardiovascular morbidity and mortality, but its role in the development of congestive heart failure (CHF) and the role of different pollution sources in cardiovascular disease remain uncertain. Participants were enrolled in the Malmö Diet and Cancer cohort in 1991–1996 with information on lifestyle and clinical indicators of cardiovascular disease. The cohort participants were followed through registers until 2016. Annual total and local source-specific concentrations of particulate matter less than 10 μm and 2.5 μm (PM 10 and PM 2.5), black carbon (BC), and nitrogen oxides (NO x) from traffic, residential heating, and industry were assigned to each participant's address throughout the study period. Cox proportional hazards models adjusted for possible confounders was used to estimate associations between air pollution 1–5 years prior to outcomes of incident CHF, fatal myocardial infarction (MI), major adverse coronary events (MACE), and ischemic stroke. Air pollution exposure levels (mean annual exposures to PM 2.5 of 11 μg/m3 and NO x of 26 μg/m3) within the cohort were moderate in terms of environmental standards. After adjusting for confounders, we observed statistically significant associations between NO x and CHF (hazard ratio [HR] 1.11, 95% confidence interval [CI] 1.01–1.22) and NO x and fatal MI (HR 1.10, 95%CI 1.01–1.20) per interquartile range (IQR) of 9.6 μg/m3. In fully adjusted models, the estimates were similar, but the precision worse. In stratified analyses, the associations were stronger in males, ever-smokers, older participants, and those with baseline carotid artery plaques. Locally emitted and traffic-related air pollutants generally showed positive associations with CHF and fatal MI. There were no associations between air pollution and MACE or stroke. In an area with low to moderate air pollution exposure, we observed significant associations of long-term residential NO x with increased risk of incident CHF and fatal MI, but not with coronary events and stroke. • Risks of heart failure and fatal MI were associated with long-term NO x exposure. • Risk estimates were stronger for traffic-related pollution than for other sources. • NO x -associated risks were stronger in men, ever-smokers, and older participants. • Risk estimates were sensitive to adjustment for area-level socio-economy. • Air pollution was not associated with risk of MACE and stroke in adjusted models. [ABSTRACT FROM AUTHOR]