Monetary explanations of the Great Depression: a selective survey of empirical evidence

Seventy years after the Great Depression, economists still debate the causes of this economic catastrophe. Two leading explanations are distinguished by whether or not the Federal Reserve’s monetary policies are perceived as being chiefly responsible for propagating and magnifying the initial contraction into a depression. ; This article surveys recent modeling efforts and empirical work that examine aggregate explanations for the Great Depression from both the extensive literature using vector autoregression techniques and the more recent literature using dynamic stochastic general equilibrium modeling. Neither of these approaches has yielded a consensus about the causes of the depression. ; Data alone are insufficient to distinguish the precise role of monetary policy during that period. The modeling strategies impose restrictions that help isolate the meaningful economic interactions in the data. In each literature, the ways in which the respective models identify monetary policy can differ substantially, and these differences are why monetary policy shocks may or may not explain much of the output contraction. Also, these modeling approaches vary in their ability to capture important institutional features of the banking and financial system. ; The authors believe that the search for one conclusive empirical study of the Great Depression is futile. The most promising path for future research models, they conclude, will entail a sharper focus on the financial sector, a refined specification of how monetary policy affects the real economy, and further methods to incorporate elements of labor market frictions.

Mixing and transient interface condensation of a liquid hydrogen tank

Experiments were conducted to investigate the effect of axial jet-induced mixing on the pressure reduction of a thermally stratified liquid hydrogen tank. The tank was nearly cylindrical, having a volume of about 0.144 cu m with 0.559 m in diameter and 0.711 m long. A mixer/pump unit, which had a jet nozzle outlet of 0.0221 m in diameter was located 0.178 m from the tank bottom and was installed inside the tank to generate the axial jet mixing and tank fluid circulation. The liquid fill and jet flow rate ranged from 42 to 85 percent (by volume) and 0.409 to 2.43 cu m/hr, respectively. Mixing tests began with the tank pressure ranging from 187.5 to 238.5 kPa at which the thermal stratification results in 4.9 to 6.2 K liquid sub cooling. The mixing time and transient vapor condensation rate at the liquid-vapor interface are determined. Two mixing time correlations, based on the thermal equilibrium and pressure equilibrium, are developed. Both mixing time correlations are expressed as functions of system and buoyancy parameters and compared well with other experimental data. The steady state condensation rate correlation of Sonin et al. based on steam-water data is modified and expressed as a function of jet subcooling. The limited liquid hydrogen data of the present study shows that the modified steady state condensation rate correlation may be used to predict the transient condensation rate in a mixing process if the instantaneous values of jet sub cooling and turbulence intensity at the interface are employed

Mutu Kulit Glase Dari Kulit Domba Peranakan Merino

This research used four pieces of good quality merino descendent sheep skin and four pieces of good quality local sheep of glace leather produced from merino descendent sheep skin to that one from local sheep skin. Either merino descendent sheep skins or the local ones were processed into glase leather through the ordinary tanning method. Glace leather output from this research were visual investigated and physical tested. Statistical analysys points out that there is unsignify difference (P ≼ 0,05) the influence of the species either it is merino and the stretch of glaze leather. It is also unsignify difference (P ≼ 0,05) the influence of the species either it is merino descendent sheep skin or the local one to the quality of glaze leather.Pratical meaning of this research is that merino descendent sheep skin may be tanned into glaze leather having same quality to that one from local sheep skins

Treatment of Industrial Wastewater Using Electrocoagulation

The aim of this thesis was to evaluate the potential use of electrocoagulation in the treatment of carbide slurry, which is wastewater generated during the production of acetylene. Several experiments using an electrochemical batch reactor were carried out at different current densities, ranging between 140-290 A/m2. Pure air (EA system) and 10% of carbon dioxide in air (CA system) were supplied to ensure good mixing and solution homogeneity. Aluminum plates were used as electrodes, spaced apart and connected to a DC power supply. After 3 hours, samples from treated effluent and waste slurry were collected and analyzed for total dissolved solids (TDS), total hardness (TH), and chemical oxygen demand (COD), in addition to electrical conductivity (EC). Response surface methodology (RSM) was used to design a matrix of experiments in order to optimize the conditions for the treatment process and improve product quality over that achieved by current conditions. Box-Behnken design (BBD) is a tool for multivariable optimization. It could be concluded that the quality of the treated wastewater as well as the generated by-products could be enhanced through controlling the operations in the electrochemical reactor. The highest reduction efficiencies for the EA system were 47.5%, 47.8%, 69.7%, 36.1%, 71.4% and 53% for COD, TH, EC, pH, TDS and salinity, respectively under specific conditions and the overall optimum conditions for the highest % reduction is under 12, 27.5 and 284 A/m2 as pH, temperature and current density, respectively. On the other hand, for the CA system, the highest reduction efficiencies were 42%, 75%, 73%, 46, 73 and 74% for COD, TH, EC, pH, TDS and salinity, respectively under specific conditions and the overall optimum conditions for the highest % reduction is under 12, 35 and 213.5 A/m2 as pH, temperature and current density, respectively. The highest CO2 capture efficiency was 84%

Characterization of novel beta-galactosidase activity that contributes to glycoprotein degradation and virulence in Streptococcus pneumoniae.

The pneumococcus obtains its energy from the metabolism of host glycosides. Therefore, efficient degradation of host glycoproteins is integral to pneumococcal virulence. In search of novel pneumococcal glycosidases, we characterized the Streptococcus pneumoniae strain D39 protein encoded by SPD_0065 and found that this gene encodes a beta-galactosidase. The SPD_0065 recombinant protein released galactose from desialylated fetuin, which was used here as a model of glycoproteins found in vivo. A pneumococcal mutant with a mutation in SPD_0065 showed diminished beta-galactosidase activity, exhibited an extended lag period in mucin-containing defined medium, and cleaved significantly less galactose than the parental strain during growth on mucin. As pneumococcal beta-galactosidase activity had been previously attributed solely to SPD_0562 (bgaA), we evaluated the contribution of SPD_0065 and SPD_0562 to total beta-galactosidase activity. Mutation of either gene significantly reduced enzymatic activity, but beta-galactosidase activity in the double mutant, although significantly less than that in either of the single mutants, was not completely abolished. The expression of SPD_0065 in S. pneumoniae grown in mucin-containing medium or tissues harvested from infected animals was significantly upregulated compared to that in pneumococci from glucose-containing medium. The SPD_0065 mutant strain was found to be attenuated in virulence in a manner specific to the host tissue

Towards integrated control of varroa: effect of variation in hygienic behaviour among honey bee colonies on mite population increase and deformed wing virus incidence

Hygienic behaviour in the honey bee, Apis mellifera, is the uncapping and removal of dead, diseased or infected brood from sealed cells by worker bees. We determined the effect of hygienic behaviour on varroa population growth and incidence of deformed wing virus (DWV), which can be transmitted by varroa. We treated 42 broodless honey bee colonies with oxalic acid in early January 2013 to reduce varroa populations to low levels, which we quantified by extracting mites from a sample of worker bees. We quantified varroa levels, again when the colonies were broodless, 48 weeks later. During the summer the hygienic behaviour in each colony was quantified four times using the Freeze Killed Brood (FKB) removal assay, and ranged from 27.5 % to 100 %. Varroa population increased greatly over the season, and there was a significant negative correlation between varroa increase and FKB removal. This was entirely due to fully hygienic colonies with >95 % FKB having only 43 % of the varroa build up of the less hygienic colonies.None of the 14 colonies with >80 % FKB removal had overt symptoms of DWV, whilst 36 % of the less hygienic colonies did. Higher levels of FKB removal also correlated significantly with lower numbers of DWV RNA copies in worker bees, but not in varroa mites. On average, fully hygienic colonies had c. 10,000 times less viral RNA than less hygienic colonies

Varactor diodes for millimeter and submillimeter wavelengths

Whisker-contacted GaAs Schottky barrier varactor diodes are the most common high-frequency multiplier element in use today. They are inherently simple devices that have very high frequency response and have been used to supply local oscillator power for Schottky heterodyne receivers to frequencies approaching 700 GHz. This paper discusses the development of improved varactor diode technology for space based applications at millimeter and submillimeter wavelengths