Oil and stock returns: Evidence from European industrial sector indices in a time-varying environment

The time-varying correlation between oil prices returns and European industrial sector indices returns, considering the origin of the oil price shock, is investigated. A time-varying multivariate heteroskedastic framework is employed to test the above hypothesis based on data from 10 European sectors. The contemporaneous correlations suggest that the relationship between sector indices and oil prices change over time and they are industry specific. In addition, the supply-side oil price shocks result in low to moderate positive correlation levels, the precautionary demand oil price shocks lead to almost zero correlation levels, whereas the aggregate demand oil price shocks generate significant changes in the correlation levels (either positive or negative). Both the origin of the oil price shock and the type of industry are important determinants of the correlation level between industrial sectors’ returns and oil prices. Prominent among the results is the fact that during the financial crisis of 2008 some sectors were providing diversification opportunities to investors dealing with the crude oil market

Vitamin Status as a Determinant of Serum Homocysteine Concentration in Type 2 Diabetic Retinopathy

We investigated the association of serum homocysteine levels and vitamin status with type 2 diabetic retinopathy. This study included 65 patients with and 75 patients without diabetic retinopathy. Patients with diabetic retinopathy had significantly higher serum homocysteine levels P<0.001, higher prevalence of hyperhomocysteinemia P<0.001, lower serum folic acid P<0.001, and vitamin B12 (P=0.014) levels than those without diabetic retinopathy. Regression analysis revealed that homocysteine was an independent risk factor for diabetic retinopathy and there was a threshold in its serum level (13.7 μmol/L), above which the risk of diabetic retinopathy greatly increases (OR=1.66, P=0.001). Folic acid was associated with decreased odds for diabetic retinopathy (OR=0.73, P<0.001). There was a threshold in serum vitamin B12 level (248.4 pg/mL), below which serum homocysteine concentration significantly increases with decreasing serum vitamin B12 (P=0.003). Our findings suggest that hyperhomocysteinemia is an independent risk factor for the development and progression of diabetic retinopathy. Decreased serum levels of folic acid and vitamin B12, through raising serum homocysteine concentrations, may also affect the diabetic retinopathy risk

Financial and monetary policy responses to oil price shocks: evidence from oil-importing and oil-exporting countries

In this study, we investigate the financial and monetary policy responses to oil price shocks using a Structural VAR framework. We distinguish between net oil-importing and net oil-exporting countries. Since the 80s, a significant number of empirical studies have been published investigating the effect of oil prices on macroeconomic and financial variables. Most of these studies though, do not make a distinction between oil-importing and oil-exporting economies. Overall, our results indicate that the level of inflation in both net oil-exporting and net oil-importing countries is significantly affected by oil price innovations. Furthermore, we find that the response of interest rates to an oil price shock depends heavily on the monetary policy regime of each country. Finally, stock markets operating in net oil-importing countries exhibit a negative response to increased oil prices. The reverse is true for the stock market of the net oil-exporting countries. We find evidence that the magnitude of stock market responses to oil price shocks is higher for the newly established and/or less liquid stock market

Circuit-based interrogation of sleep control.

Sleep is a fundamental biological process observed widely in the animal kingdom, but the neural circuits generating sleep remain poorly understood. Understanding the brain mechanisms controlling sleep requires the identification of key neurons in the control circuits and mapping of their synaptic connections. Technical innovations over the past decade have greatly facilitated dissection of the sleep circuits. This has set the stage for understanding how a variety of environmental and physiological factors influence sleep. The ability to initiate and terminate sleep on command will also help us to elucidate its functions within and beyond the brain

TOI-2447 b / NGTS-29 b: a 69-day Saturn around a Solar analogue

Discovering transiting exoplanets with relatively long orbital periods ($>$10 days) is crucial to facilitate the study of cool exoplanet atmospheres ($T_{\rm eq} < 700 K$) and to understand exoplanet formation and inward migration further out than typical transiting exoplanets. In order to discover these longer period transiting exoplanets, long-term photometric and radial velocity campaigns are required. We report the discovery of TOI-2447 b ($=$ NGTS-29b), a Saturn-mass transiting exoplanet orbiting a bright (T=10.0) Solar-type star (T$_{\rm eff}$=5730 K). TOI-2447 b was identified as a transiting exoplanet candidate from a single transit event of 1.3% depth and 7.29 h duration in $TESS$ Sector 31 and a prior transit event from 2017 in NGTS data. Four further transit events were observed with NGTS photometry which revealed an orbital period of P=69.34 days. The transit events establish a radius for TOI-2447 b of $0.865 \pm 0.010\rm R_{\rm J}$, while radial velocity measurements give a mass of $0.386 \pm 0.025 \rm M_{\rm J}$. The equilibrium temperature of the planet is $414$ K, making it much cooler than the majority of $TESS$ planet discoveries. We also detect a transit signal in NGTS data not caused by TOI-2447 b, along with transit timing variations and evidence for a $\sim$150 day signal in radial velocity measurements. It is likely that the system hosts additional planets, but further photometry and radial velocity campaigns will be needed to determine their parameters with confidence. TOI-2447 b/NGTS-29b joins a small but growing population of cool giants that will provide crucial insights into giant planet composition and formation mechanisms.Comment: 16 pages, 12 figures. Accepted for publication in MNRA

NGTS-31b and NGTS-32b: two inflated hot jupiters orbiting subgiant stars

We present the discoveries of NGTS-31b(= TOI-2721), and NGTS-32b, two hot Jupiters from the Next Generation Transit Survey (NGTS) transiting slightly evolved stars. The orbital periods, radii, and masses are 4.16 and 3.31 d, 1.61 and 1.42 RJ, and 1.12 and 0.57 MJ, respectively. Both planets have an incident stellar flux significantly above the threshold where inflation occurs, with both planets showing signs of inflation. These planets have widely different equilibrium temperatures than other hot Jupiters of similar mass and radius, with NGTS-31b having a significantly lower temperature, and NGTS-32b being hotter. This dichotomy raises the question of how prevalent the roles of other inflation mechanisms are in the radius anomaly phenomena and will help further constrain different inflationary models

TOI-2447 b / NGTS-29 b: a 69-day Saturn around a Solar analogue

Discovering transiting exoplanets with relatively long orbital periods (>10 d) is crucial to facilitate the study of cool exoplanet atmospheres (Teq < 700 K) and to understand exoplanet formation and inward migration further out than typical transiting exoplanets. In order to discover these longer period transiting exoplanets, long-term photometric, and radial velocity campaigns are required. We report the discovery of TOI-2447 b (=NGTS-29 b), a Saturn-mass transiting exoplanet orbiting a bright (T = 10.0) Solar-type star (Teff = 5730 K). TOI-2447 b was identified as a transiting exoplanet candidate from a single transit event of 1.3 per cent depth and 7.29 h duration in TESS Sector 31 and a prior transit event from 2017 in NGTS data. Four further transit events were observed with NGTS photometry which revealed an orbital period of P = 69.34 d. The transit events establish a radius for TOI-2447 b of 0.865±0.010RJ, while radial velocity measurements give a mass of 0.386±0.025MJ. The equilibrium temperature of the planet is 414 K, making it much cooler than the majority of TESS planet discoveries. We also detect a transit signal in NGTS data not caused by TOI-2447 b, along with transit timing variations and evidence for a ~150 d signal in radial velocity measurements. It is likely that the system hosts additional planets, but further photometry and radial velocity campaigns will be needed to determine their parameters with confidence. TOI-2447 b/NGTS-29 b joins a small but growing population of cool giants that will provide crucial insights into giant planet composition and formation mechanisms