Nanotechnology uses the unique properties of objects that function as a unit within the overall size range of 1-1,000 nanometres. The engineering of nanostructure materials, including nanoparticles, ...nanoemulsions or nanotubules, holds great promise for the development of new immunomodulatory agents, as such nanostructures can be used to more effectively manipulate or deliver immunologically active components to target sites. Successful applications of nanotechnology in the field of immunology will enable new generations of vaccines, adjuvants and immunomodulatory drugs that aim to improve clinical outcomes in response to a range of infectious and non-infectious diseases.
MEASURING ECONOMIC POLICY UNCERTAINTY BAKER, SCOTT R.; BLOOM, NICHOLAS; DAVIS, STEVEN J.
The Quarterly journal of economics,
11/2016, Letnik:
131, Številka:
4
Journal Article
Recenzirano
Odprti dostop
We develop a new index of economic policy uncertainty (EPU) based on newspaper coverage frequency. Several types of evidence—including human readings of 12,000 newspaper articles—indicate that our ...index proxies for movements in policy-related economic uncertainty. Our U.S. index spikes near tight presidential elections, Gulf Wars I and II, the 9/11 attacks, the failure of Lehman Brothers, the 2011 debt ceiling dispute, and other major battles over fiscal policy. Using firm-level data, we find that policy uncertainty is associated with greater stock price volatility and reduced investment and employment in policy-sensitive sectors like defense, health care, finance, and infrastructure construction. At the macro level, innovations in policy uncertainty foreshadow declines in investment, output, and employment in the United States and, in a panel vector autoregressive setting, for 12 major economies. Extending our U.S. index back to 1900, EPU rose dramatically in the 1930s (from late 1931) and has drifted upward since the 1960s.
The increasing availability of data derived from linked consumer financial accounts has the potential to dramatically expand the potential for research. Examining the most comprehensive existing set ...of linked-account data, consisting of transaction and balance sheet data for millions of Americans, I demonstrate the power and versatility of such sources. I discuss advantages and concerns arising from this type of data andmatch a range of distributionalmoments to external sources. As one application, I test consumption elasticities across households with varying levels, and types, of debt. I find that heterogeneity in consumption elasticity can be explained entirely by credit and liquidity.
The use of chlorophyll fluorescence to monitor photosynthetic performance in algae and plants is now widespread. This review examines how fluorescence parameters can be used to evaluate changes in ...photosystem II (PSII) photochemistry, linear electron flux, and CO(2) assimilation in vivo, and outlines the theoretical bases for the use of specific fluorescence parameters. Although fluorescence parameters can be measured easily, many potential problems may arise when they are applied to predict changes in photosynthetic performance. In particular, consideration is given to problems associated with accurate estimation of the PSII operating efficiency measured by fluorescence and its relationship with the rates of linear electron flux and CO(2) assimilation. The roles of photochemical and nonphotochemical quenching in the determination of changes in PSII operating efficiency are examined. Finally, applications of fluorescence imaging to studies of photosynthetic heterogeneity and the rapid screening of large numbers of plants for perturbations in photosynthesis and associated metabolism are considered.
This paper presents, for the first time, spatial and temporal occurrence of a comprehensive set of >60 pharmaceuticals, illicit drugs and their metabolites in wastewater (7 wastewater treatment ...plants utilising different treatment technologies) and a major river in the UK over a 12month period. This paper also undertakes a comparison of the efficiency of processes utilised during wastewater treatment and it discusses under-researched aspects of pharmaceuticals and illicit drugs in the environment including sorption to solids and stereoselectivity in the fate of chiral drugs during wastewater treatment and in receiving waters.
The removal efficiency of analytes strongly depended on the type of wastewater treatment technology employed and denoted <50% or >60% in the case of tricking filter and activated sludge respectively. It should be stressed, however, that the removal rate was highly variable for different groups of compounds. A clear increase in the cumulative concentration of all monitored compounds was observed in receiving waters; thus highlighting the impact of WWTP discharge on water quality and the importance of the removal efficiency of WWTPs. No seasonal variation was observed with regard to the total load of targeted compounds in the river each month. The concentration of each analyte was largely dependent on rainfall and the dilution factor of WWTP discharge. These results indicate that although the drugs of abuse are not present at very high concentrations in river water (typically low ngL−1 levels), their occurrence and possible synergic action is of concern, and the study of multiple groups of drugs of abuse is of significant importance.
•Spatial & temporal occurrence of >60 drugs (of abuse) in the UK is investigated.•WWTP removal efficiency of drugs (average <70%) depends on technology employed.•Up to 23kg of studied drugs are carried daily in studied river.•Enantioselective degradation of drugs occurs during WWTP treatment and in receiving waters.•Sorption of drugs of abuse to suspended solids should not be ignored.
A double-exchange interaction (DEI) was demonstrated to boost the oxygen evolution reaction (OER) in spinel oxides. DEI was ignited by synergistic actions of constructing nanoheterojunctions and ...creating oxygen vacancy (VO) in spinel NiCo2O4. DEI between octahedrally coordinated Ni and Co resulted in the generation of superior OER active centers Co(3−δ)+ and Ni3+. The multiple synergistic effects empower the electrocatalyst with exceptional OER activity, with an overpotential of 270 ± 3 mV at 10 mA/cm2 and a Tafel slope of 39 mV/dec, both of which are among the best values for NiCo2O4-based nanostructures, and even better than those for IrO2 and RuO2.
Nonalcoholic fatty liver disease (NAFLD) is a global epidemic in obese children and adults, and the onset might have fetal origins. A growing body of evidence supports the role of developmental ...programming, whereby the maternal environment affects fetal and infant development, altering the risk profile for disease later in life. Human and nonhuman primate studies of maternal obesity demonstrate that risk factors for pediatric obesity and NAFLD begin in utero. The pathologic mechanisms for NAFLD are multifactorial but have centered on altered mitochondrial function/dysfunction that might precede insulin resistance. Compared with the adult liver, the fetal liver has fewer mitochondria, low activity of the fatty acid metabolic enzyme carnitine palmitoyl-CoA transferase-1, and little or no gluconeogenesis. Exposure to excess maternal fuels during fetal life uniquely alters hepatic fatty acid oxidation, tricarboxylic acid cycle activity, de novo lipogenesis, and mitochondrial health. These events promote increased oxidative stress and excess triglyceride storage, and, together with altered immune function and epigenetic changes, they prime the fetal liver for NAFLD and might drive the risk for nonalcoholic steatohepatitis in the next generation.
Abstract
No previous infectious disease outbreak, including the Spanish Flu, has affected the stock market as forcefully as the COVID-19 pandemic. In fact, previous pandemics left only mild traces on ...the U.S. stock market. We use text-based methods to develop these points with respect to large daily stock market moves back to 1900 and with respect to overall stock market volatility back to 1985. We also evaluate potential explanations for the unprecedented stock market reaction to the COVID-19 pandemic. The evidence we amass suggests that government restrictions on commercial activity and voluntary social distancing, operating with powerful effects in a service-oriented economy, are the main reasons the U.S. stock market reacted so much more forcefully to COVID-19 than to previous pandemics in 1918–1919, 1957–1958, and 1968.
This Review chronicles the progress made in the field of small fluorocarbon synthesis since their invention in the early 1930s by Thomas Midgley, Jr., and his coworkers, with special focus on their ...application as refrigerants, foam expansion agents, aerosol propellants, and precision solvents. Divided into four generations of C1–C4 halocarbons from CFCs through HCFCs, HFCs, and HFOs, the merits and challenges of each will be discussed in the context of market demands, as well as the evolution of industrial manufacturing methods. Vital transformations, such as exchange (Swarts) fluorination, hydrodehalogenation, dehydrohalogenation, and additions (Kharasch or Prins) will feature prominently and will be discussed in detail, as well as catalysts therefor. Of the myriad of fluorocarbons described herein, the models which have reached particular commercial significance (such as chlorodifluoromethane and 1,1,1,2-tetrafluoroethane) are given special consideration as flag-bearers for the generation to which they belong. Regulatory constraints to which this industry is bound will be outlined in brief, as well as an introduction to safety designations and nomenclature put forth by the American Society for Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). This Review includes predominantly works which can only be found in the patent literature, but should be of equal interest to both academic and industrial practitioners of the art as it centers on fundamentals of organofluorine chemistry, which could equally be applied to the synthesis of larger molecules and building blocks for other applications.
Chlorophyll fluorescence has been routinely used for many years to monitor the photosynthetic performance of plants non-invasively. The relationships between chlorophyll fluorescence parameters and ...leaf photosynthetic performance are reviewed in the context of applications of fluorescence measurements to screening programmes which seek to identify improved plant performance. The potential role of chlorophyll fluorescence imaging in increasing both the sensitivity and throughput of plant screening programmes is examined. Finally, consideration is given to possible specific applications of chlorophyll fluorescence for screening of plants for tolerance to environmental stresses and for improvements in glasshouse production and post-harvest handling of crops.
PDF
