A modified petri dish method for rust infection of excised leaves

Zusammenfassung Es wird eine Methode beschrieben, um festzustellen, ob ein Rostpilz homo- oder heterothallisch ist. Hiefür wird der Pilz auf einem geeigneten Medium in einer Petri-Schale gezüchtet. Die Vor- und Nachteile dieser Methode werden erörtert.

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Junior Research Fellow of the National Institute of Sciences of India.     

A threshold model for the French franc/deutschmark exchange rate

The behaviour of the French franc/deutschmark exchange rate is examined in this paper. During the time period studied, these currencies were constrained to lie within prescribed bands relative to one another and the usual random walk explanation of the exchange rate may not be appropriate. The data are examined for evidence of non-linear structure and it is shown that a piecewise linear SETAR model provides a better explanation and superior forecasting performance than a random walk.     

Google Trends and the forecasting performance of exchange rate models

In this paper, we use Google Trends data for exchange rate forecasting in the context of a broad literature review that ties the exchange rate movements with macroeconomic fundamentals. The sample covers 11 OECD countries’ exchange rates for the period from January 2004 to June 2014. In out‐of‐sample forecasting of monthly returns on exchange rates, our findings indicate that the Google Trends search query data do a better job than the structural models in predicting the true direction of changes in nominal exchange rates. We also observed that Google Trends‐based forecasts are better at picking up the direction of the changes in the monthly nominal exchange rates after the Great Recession era (2008–2009). Based on the Clark and West inference procedure of equal predictive accuracy testing, we found that the relative performance of Google Trends‐based exchange rate predictions against the null of a random walk model is no worse than the purchasing power parity model. On the other hand, although the monetary model fundamentals could beat the random walk null only in one out of 11 currency pairs, with Google Trends predictors we found evidence of better performance for five currency pairs. We believe that these findings necessitate further research in this area to investigate the extravalue one can get from Google search query data.     

A quick and modified Winkler-method for measuring O2-concumption of aquatic animals

Summary A modified procedure for measuring O₂-consumption, based on Winkler-method, is described. Instead of KI and HCl (or H₂SO₄) triphenylmethane-dye leukoberbelinblue I and citric acid are used.Acknowledgment. Md. B. expresses his gratitude to DAAD (German Academic Exchange Service, Bonn) for awarding him a post-doctoral fellowship, during the tenure of which this investigation was carried out.     

Structural,VAR and BVAR models of exchange rate determination: A comparison of their forecasting performance

This paper compares the out-of-sample forecasting accuracy of a wide class of structural, BVAR and VAR models for major sterling exchange rates over different forecast horizons. As representative structural models we employ a portfolio balance model and a modified uncovered interest parity model, with the latter producing the more accurate forecasts. Proper attention to the long-run properties and the short-run dynamics of structural models can improve on the forecasting performance of the random walk model. The structural model shows substantial improvement in medium-term forecasting accuracy, whereas the BVAR model is the more accurate in the short term. BVAR and VAR models in levels strongly out predict these models formulated in difference form at all forecast horizons.     

A qualitative difference between certain H-2 and Non-H-2 antigens responsible for a similar graft-rejection rate

Zusammenfassung Gezeigt wird, dass «schwache» Histokompatibilitätsantigene weniger sensibilisieren als «starke», auch wenn beide eine quantitativ ähnliche Transplantationsbarriere darstellen. Auf qualitative Unterschiede zwischen diesen Antigenen nach Vorbehandlung des Rezipienten mit lebenden Milzzellen von Mäusen wird hingewiesen.     

A very simple trick to produce controlled CO2 concentrations in the gas phase overlying cell cultures

Résumé Du NaHCO₃ protégé par une enveloppe de cachet pharmaceutique ne commence à être décomposé par H₃PO₄ qu'après environ une minute. Cela permet de produire un taux déterminé de CO₂ dans l'atmosphère d'un récipient clos où sont placées les cultures de cellules (souches, embryonnaires, moëlle osseuse, etc.).     

Do the respiratory muscles and lung receptors influence the respiratory sensitivity to CO2?

, CO₂. CO₂ CO₂ , . , CO₂, CO₂ . , , CO₂, CO₂ .     

土壤动物对大气CO2浓度升高响应研究的进展

土壤动物在农业生态系统腐屑食物网中占有重要地位,它们参与土壤有机质分解,植物管养矿化及养分循环作用,国外许多试验表明,土壤运动及其多样性对全球变化,尤其是大气CO2浓度升高产生正向,中性和负向的响应,本文首先介绍了土壤动物的分类在养分循环中的作用,其次论述了土壤动物对大气CO2浓度升高响应的研究进展,最后提出我国近期将优先研究的几项任务。     

DDT: the degradation of ring-labeled 14C-DDT to 14CO2 in the rat.

Ring fission of p, p'-DDT was studied in the rat following a single oral dose of 0.74 mg/kg (1.04 muCi) of uniformly ring-labeled 14C-DDT. Expired air was passed through a solution of ethanolamine-ethylene glycol monomethyl ether (1:2) to trap 14CO2. A total of 1.6% of the radioactivity administered was recovered in the expired air collected continually for 10 days, indicating that while degradation of the phenyl moiety is not a major route of p,p'-DDT metabolism in the rat, it is equal to the urinary excretion. Nevertheless, these results represent the most radical change accomplished in vivo of a residual insecticide yet reported in mammals.     

DDT: The degradation of ring-labeled14C-DDT to14CO2 in the rat

Summary Ring fission ofp, p-DDT was studied in the rat following a single oral dose of 0.74 mg/kg (1.04 Ci) of uniformly ring-labeled¹⁴C-DDT. Expired air was passed through a solution of ethanolamine-ethylene glycol monomethyl ether (12) to trap¹⁴CO₂. A total of 1.6% of the radioactivity administered was recovered in the expired air collected continually for 10 days, indicating that while degradation of the phenyl moiety is not a major route pfp, p-DDT metabolism in the rat, it is equal to the urinary excretion. Nevertheless, these results represent the most radical change accomplished in vivo of a residual insecticide yet reported in mammals.Acknowledgment. We acknowledge the secretarial work of Ms.Elaine Smolko. This study was supported by NIH fellowship No. 1 F22 ES01723-01 and No. HL16264.     

A practicable variant of the ion exchange method for the radiometric estimation of ornithine decarboxylase activity

A known ornithine decarboxylase assay working with ion exchange separation of [3H]ornithine and [3H]putrescine has been revised. The assay can be performed in disposable 1.5 ml vessels with a total of four pipetting steps. The separation of enzyme substrate and product, respectively, requires 3 h per 50 samples. The detection limit is about 50 pmoles [3H]putrescine formed.     

The real exchange rate,fiscal policy and the role of wealth an analysis of equilibrium in a monetary union

This paper is concerned with the adjustment processes within a potential European monetary union and looks in particular at permanent asymmetric shocks that require an adjustment in a country's (or region's) real exchange rate. We first consider some of the implications of EMU and the question of asymmetries within the European economy. The presence of asymmetries and, in particular, different institutional structures in labour markets is a potential source of tension within a union and it could make a union difficult to sustain. However, automatic adjustment processes will be at work within a monetary union as a result of changes in relative price levels, which change real exchange rates, and also as a result of changes in wealth stocks. We use our econometric world model, NIGEM, to investigate the effects of asymmetric fiscal expansions and real exchange rate misalignments within a monetary union. In order to quantify the effects of such permanent asymmetric shocks we have introduced wealth into our model. Our simulations suggest that the principal impact of the fiscal expansion on both output and the price level will occur within the country in which the expansion occurs. Short-term gains are crowded out in the medium term, and while monetary union reduces crowding out in the short term, it increases the rate at which crowding out occurs thereafter. We also analyse the effects of real exchange rate misalignments and find that the processes of adjustment may be very protracted. This could cause strain on the union as adjustment costs are shared unequally.     

A practicable variant of the ion exchange method for the radiometric estimation of ornithine decarboxylase activity

Summary A known ornithine decarboxylase assay working with ion exchang separation of [³H]ornithine and [³H]putrescine has been revised. The assay can be performed in disposable 1.5 ml vessels with a total of four pipetting steps. The separation of enzyme substrate and product, respectively, requires 3 h per 50 samples. The detection limit is about 50 pmoles [³H]putrescine formed.     

A dialysis rate method for the measurement of free iodothyronine and steroid hormones in blood

From the dialysis rate of a small amount of tracer hormone from a serum sample through a semipermeable membrane towards an identical serum sample, the free hormone fraction can be calculated. This method is free from a number of artefacts that may occur in equilibrium dialysis.