We examine the properties and forecast performance of multiplicative volatility specifications that belong to the class of generalized autoregressive conditional heteroskedasticity–mixed-data ...sampling (GARCH-MIDAS) models suggested in Engle, Ghysels, and Sohn (Review of Economics and Statistics, 2013, 95, 776–797). In those models volatility is decomposed into a short-term GARCH component and a long-term component that is driven by an explanatory variable. We derive the kurtosis of returns, the autocorrelation function of squared returns, and the R2 of a Mincer–Zarnowitz regression and evaluate the QMLE and forecast performance of these models in a Monte Carlo simulation. For S&P 500 data, we compare the forecast performance of GARCH-MIDAS models with a wide range of competitor models such as HAR (heterogeneous autoregression), realized GARCH, HEAVY (high-frequency-based volatility) and Markov-switching GARCH. Our results show that the GARCH-MIDAS based on housing starts as an explanatory variable significantly outperforms all competitor models at forecast horizons of 2 and 3 months ahead.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Nickel phosphide catalysts (Ni12P5 and Ni2P) preferentially cleave sterically hindered 3C–O bonds over unhindered 2C–O bonds, and Ni2P is up to 50 times more selective toward 3C–O bond cleavage than ...Ni. Here, we combine kinetic measurements, in situ infrared spectroscopy, and density functional theory (DFT) calculations to describe the mechanism for C–O bond rupture over Ni, Ni12P5, and Ni2P catalysts. Steady-state rate measurements and DFT calculations of C–O bond rupture within 2-methyltetrahydrofuran (MTHF) show that quasi-equilibrated MTHF adsorption and dehydrogenation steps precede kinetically relevant C–O bond rupture at these conditions (1–50 kPa MTHF; 0.1–6 MPa H2; 543 K). Rates for 3C–O and 2C–O bond rupture are inhibited by H2, and the ratio of these rates increases with H21/2, suggesting that the composition of the reactive intermediates for 3C–O and 2C–O rupture differs by one H atom. Site-blocking CO*, NH3*, and H* inhibit rates without altering the ratio of 3C–O to 2C–O bond rupture, indicating that these C–O bond rupture precursors and transition states bind to identical active sites. DFT-based predictions suggest that these sites are exposed ensembles of 3 Ni atoms on Ni(111) and Ni2P(001) and 4 Ni atoms on Ni12P5(001) and that the incorporation of P disrupts extended Ni ensembles and alters the reactivity of the Ni. Increasing the phosphorus to nickel ratio (P:Ni) decreases measured and DFT-predicted activation enthalpies (ΔH ‡, 473–583 K) for 3C–O bond rupture relative to that of 2C–O bond rupture. Selectivity differences between specific C–O bonds within MTHF reflect differences in the H content of reactive intermediates, activation enthalpy barriers, and P:Ni of Ni, Ni12P5, and Ni2P nanoparticles.
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IJS, KILJ, NUK, PNG, UL, UM
Luminescent gold nanoclusters (Au NCs) are a promising probe material for selective chemical sensing. However, low luminescent intensity and an incomplete understanding of the mechanistic origin of ...the luminescence limit their practical implementation. We induced glutathione-capped Au NCs to aggregate within silica-coated microcapsular structures using polymer–salt aggregate self-assembly chemistry. The encapsulated NCs have a 5× luminescence enhancement compared to free Au NCs and can detect Cr(VI) at concentrations as low as 6 ppb (=0.12 μM CrO4 2–) through luminescence quenching, compared to free Au NCs, which have a limit of detection (LOD) of 52 ppb (=1 μM CrO4 2–). The LOD is 16× lower than the United States Environmental Protection Agency maximum contaminant level for total chromium (Cr(III) + Cr(VI), 100 ppb) in drinking water. No pH adjustment is needed using the encapsulated Au NCs, unlike the case for free Au NCs. The luminescent microcapsule material can sense Cr(VI) in simulated drinking water with a ∼20–30 ppb LOD, serving as a possible basis for a practical Cr(VI) sensor.
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IJS, KILJ, NUK, PNG, UL, UM
We investigate the relationship between long-term US stock market risks and the macroeconomic environment using a two-component GARCH-MIDAS model. Our results show that macroeconomic variables are ...important determinants of the secular component of stock market volatility. Among the various macro variables in our dataset the term spread, housing starts, corporate profits and the unemployment rate have the highest predictive ability for long-term stock market volatility. While the term spread and housing starts are leading variables with respect to stock market volatility, for industrial production and the unemployment rate expectations data from the Survey of Professional Forecasters regarding the future development are most informative.
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BFBNIB, FZAB, GIS, IJS, INZLJ, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZRSKP
Despite two years of intense global research activity, host genetic factors that predispose to a poorer prognosis of COVID-19 infection remain poorly understood. Here, we prioritise eight robust ...(e.g., ELF5) or suggestive but unreported (e.g., RAB2A) candidate protein mediators of COVID-19 outcomes by integrating results from the COVID-19 Host Genetics Initiative with population-based plasma proteomics using statistical colocalisation. The transcription factor ELF5 (ELF5) shows robust and directionally consistent associations across different outcome definitions, including a >4-fold higher risk (odds ratio: 4.88; 95%-CI: 2.47-9.63; p-value < 5.0 × 10
) for severe COVID-19 per 1 s.d. higher genetically predicted plasma ELF5. We show that ELF5 is specifically expressed in epithelial cells of the respiratory system, such as secretory and alveolar type 2 cells, using single-cell RNA sequencing and immunohistochemistry. These cells are also likely targets of SARS-CoV-2 by colocalisation with key host factors, including ACE2 and TMPRSS2. In summary, large-scale human genetic studies together with gene expression at single-cell resolution highlight ELF5 as a risk gene for severe COVID-19, supporting a role of epithelial cells of the respiratory system in the adverse host response to SARS-CoV-2.
Islamic Medicine in the Middle Ages Edriss, Hawa; Rosales, Brittany N; Nugent, Connie ...
The American journal of the medical sciences,
09/2017, Volume:
354, Issue:
3
Journal Article
Peer reviewed
The Islamic culture flourished between the 9th and 13th centuries. Scholars from this era made significant contributions in mathematics, science and medicine. Caliphs and physicians built hospitals ...that provided universal care and the foundation for medical education. Physician-scientists made significant advances in medical care, surgery and pharmacology. Notable authorities include al-Razi (865-925 CE) who wrote the Kitab al-Hawi fi al-tibb (The Comprehensive Book on Medicine), a 23-volume textbook that provided the main medical curriculum for European schools into the 14th century. Ibn Sina (980-1037 CE), an extraordinary Persian polymath, wrote al Qanun fi al-Tibb (The Canon of Medicine), an encyclopedic treatment of medicine that combined his own observations with medical information from Galen and philosophy from Aristotle. Mansur (1380-1422 CE) wrote the first color illustrated book on anatomy. Other important physicians compiled information on the use of medication from plants, advanced surgical techniques, including cataract extraction and studied physiology, including the pulmonary circulation. These books and ideas provided the basis for medical care in Europe during its recovery from the Dark Ages.
Die fortschreitende Globalisierung der Wirtschaft fuhrt zu immer neuen Anderungen der internationalen Arbeitsteilung und neuen Geschaftsmoglichkeiten, womit besondere ethische Herausforderungen ...verbunden sind. Internationale Konzerne konnen sich im Rahmen der Globalisierung durch eine Standortverlagerung dem Zugriff ihrer Regierungen entziehen und die Schwachen auslandischer Staaten zu ihrem Vorteil ausnutzen. Die Unternehmen konnen nicht nur durch eine Standortwahl versuchen, ihre Kosten zu Lasten der Umwelt und der Arbeitnehmer zu minimieren, sondern auch ihre steuerliche Belastung senken. Ziel dieses Sammelbandes ist es, ethische Verfehlungen aufzuzeigen und mit Hilfe der Wirtschaftsethik Lsungsanstze herauszuarbeiten. Die Globalisierung ndert die Welt und das zwischenmenschliche Zusammenleben. Es gibt immer mehr internationale Vernetzungen, die zu immer mehr Interdependenzen fhren. Das Ergebnis der Analyse zeigt, dass vor diesem Hintergrund in allen Bereichen immer mehr Politiken global abgestimmt werden mssen. Je globaler die Welt wird, desto mehr bedarf es eines supranationalen Rechtssystems mit einer bergeordneten Organisation, die ber Sanktionsmglichkeiten verfgt, um ethisches Wirtschaftsverhalten durchzusetzen.
Biomedical research projects are becoming increasingly complex and require technological solutions that support all phases of the data lifecycle and application of the FAIR principles. At the Berlin ...Institute of Health (BIH), we have developed and established a flexible and cost-effective approach to building customized cloud platforms for supporting research projects. The approach is based on a microservice architecture and on the management of a portfolio of supported services. On this basis, we created and maintained cloud platforms for several international research projects. In this article, we present our approach and argue that building customized cloud platforms can offer multiple advantages over using multi-project platforms. Our approach is transferable to other research environments and can be easily adapted by other projects and other service providers.
This book offers guidelines for the upcoming discussions on reform, representing an attempt to work out conceptions for a better international competition order on the basis of the scientific ...approach 'law and economics'. It presents the dominant concepts of competition policy as a basis for an international competition order and formulates a synthesis. The result is a new neo-ordoliberal approach. Anti-dumping-measures are analysed of the effects on international competition and resource allocation, and alternatives and improvements are suggested. From national forms of competition policy a synthesis of international competition policies are derived. Currently reforms of the international competition order are heavily discussed and here a selection of the most important suggestions are presented, compared, and evaluated. Finally, this book offers strategies that might serve as second-best solutions, and though they may not be optimal for competition policy, they are politically feasible and an improvement on the current competition regulations. They would be a back-up in case the WTO competition regulations aren't realizable.
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