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Editorial NoteScience Policy News

Federal Republic of Germany The Annual Report for 1987 of the Deutsche Forschungsgemeinschaft (German Research Association)  相似文献   

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It is investigated whether euro area variables can be forecast better based on synthetic time series for the pre‐euro period or by using just data from Germany for the pre‐euro period. Our forecast comparison is based on quarterly data for the period 1970Q1–2003Q4 for 10 macroeconomic variables. The years 2000–2003 are used as forecasting period. A range of different univariate forecasting methods is applied. Some of them are based on linear autoregressive models and we also use some nonlinear or time‐varying coefficient models. It turns out that most variables which have a similar level for Germany and the euro area such as prices can be better predicted based on German data, while aggregated European data are preferable for forecasting variables which need considerable adjustments in their levels when joining German and European Monetary Union (EMU) data. These results suggest that for variables which have a similar level for Germany and the euro area it may be reasonable to consider the German pre‐EMU data for studying economic problems in the euro area. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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Boric acid is a slow-acting, inorganic insecticide whose mode of action has not been satisfactorily elucidated. Reported here is evidence which shows that ingested boric acid destroys the cellular lining of the foregut of German cockroaches,Blattella germanica (L.). This effect appears to be sufficient to bring about the death of the insects, perhaps ultimately by starvation. This finding is important because resistance to conventional insectivides may re-establish boric acid as a prominent cockroach control chemical.  相似文献   

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The purpose of the paper is to investigate the accuracy of forecasts derived from univariate and multivariate time-series models. An iterative method to adjust for impact assessment in univariate ARIMA models is discussed and illustrated for the German unemployment rate. Finally, we also examine the pros and cons of the impact assessment model in comparison with VAR models.  相似文献   

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Mining companies after the Gold Rush depended heavily on foreign expertise, and yet historians of mining have glorified ‘German engineering’ in America. The application of German technology in America was fraught with difficulties, and most advances were micro- rather than macro-innovations, such as Philip Deidesheimer's famous square-set timbering on the Comstock Lode. The problem began at German mining schools, such as the Freiberg Mining Academy, where Americans like Louis and Henry Janin, while they acquired advanced training and adopted an engineering ethos, struggled to learn about Mexican and American mining. Having complemented their course of study to remedy this deficiency, the brothers returned to the US intending to modernize mining on the frontier. Louis attempted the ‘Freiberg Process’ of amalgamation on the Comstock Lode, but locally developed methods proved more feasible, and the experiment failed. He came to apply his training rather toward the micro-level problem of how to reprocess amalgamation waste heaps.  相似文献   

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Summary 7-day-cultured islets from pregnant Wistar rats released at 5.6 mM glucose significantly more insulin than islets from nonpregnant rats, whereas in vivo this heigthened glucose sensitivity is lost 48 h post partum.Investigations carried out as a part of the Forschungsprojekt Diabetes mellitus und Fettstoffwechselstörungen supported by the Ministry of Health of German Democratic Republic.  相似文献   

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People are reluctant to admit mistakes. This could also be true of economic forecasters. If revisions of past forecasts are costly, then it will become optimal for forecasters to only partially adjust a past forecast in the light of new information. The unwillingness to admit to the mistake in the old forecast generates a bias of the new forecast in the direction of the old forecast. We test this hypothesis for the joint predictions of the Association of German Economic Research Institutes over the last 35 years. We find some evidence for such a bias and compute the implied unwillingness to revise forecasts. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

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Virgin German cockroach adult females release an attractant that can be extracted with organic solvents and trapped from air blown over sexually receptive females. Behavioral assays with an olfactometer showed that the attractant was produced exclusively by adult females and it elicited behavioral responses in adult males, confirming its function as a female sex pheromone. Using behavioral and electrophysiological assays, we localized the site of pheromone production on the tenth abdominal tergite where an adult female-specific gland is found. Females whose glands were ablated were significantly less attractive to males than sham-operated control females.  相似文献   

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In this paper we explore methodologies appropriate for evaluating a forecasting competition when the participants predict a number of variables that may be related to each other and are judged for a single period. Typically, forecasting competitions are judged on a variable‐by‐variable basis, but a multivariate analysis is required to determine how each competitor performed overall. We use three different multivariate tests to determine an overall winner for a forecasting competition for the German economy across 25 different institutions for a single time period using a vector of eight key economic variables. We find that neglecting the cross‐variable relationships greatly alters the outcome of the forecasting competition. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

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This paper discusses the forecasting performance of alternative factor models based on a large panel of quarterly time series for the German economy. One model extracts factors by static principal components analysis; the second model is based on dynamic principal components obtained using frequency domain methods; the third model is based on subspace algorithms for state‐space models. Out‐of‐sample forecasts show that the forecast errors of the factor models are on average smaller than the errors of a simple autoregressive benchmark model. Among the factor models, the dynamic principal component model and the subspace factor model outperform the static factor model in most cases in terms of mean‐squared forecast error. However, the forecast performance depends crucially on the choice of appropriate information criteria for the auxiliary parameters of the models. In the case of misspecification, rankings of forecast performance can change severely. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

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Zusammenfassung Behandlung vonBlattella germanica im letzten Larvenstadium mit hohen Dosen von Juvenilhormon verhindert ausser der Morphogenese auch die Bildung der neuen Cuticula und die Häutung. Die Prothoracaldrüsen der entstandenen Dauerlarven sind normal; durch anschliessende Injektion von -Ecdyson wird Cuticulasynthese induziert, die Tiere sterben jedoch in der alten Haut. Diese Befunde unterstützen die Hypothese der antagonistischen Wirkung von Juvenilhormon und Ecdyson.  相似文献   

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Summary Spherule cells are restricted to the larval stage and make up 5–16% of cells in the hemolymph. Their morphology varies between species, mainly due to the shape of their inclusions which may be oval (spheroidocytes), polyhedral (crystalloid cells), or clearly crystalline (crystal cells). These inclusions are very rich in tyrosine. They liquefy rapidly in vitro, whereby the cells become hyaline (coagulocytes).Acknowledgments. We thank Mr B. Barandun for excellent technical assistance. This investigation was supported by the Swiss National Science Foundation, grant No. 3.792.076.  相似文献   

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Posters

Gene expression and replication  相似文献   

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Science Policy News

The European Science Foundation: Excerpts from the annual report for 1987  相似文献   

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Science Policy News

European science foundation brain research programme 1990–1991  相似文献   

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Science Policy News

European Molecular Biology Laboratory [EMBL]: Excerpts from the annual report 1989  相似文献   

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