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61.
Detecting and Predicting Economic Accelerations,Recessions, and Normal Growth Periods in Real‐Time
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Christian R. Proaño 《Journal of forecasting》2017,36(1):26-42
The dichotomous characterization of the business cycle in recessions and expansions has been central in the literature over the last 50 years. However, there are various reasons to question the adequacy of this dichotomous, recession/expansion approach for our understanding of the business cycle dynamics, as well as for the prediction of future business cycle developments. In this context, the contribution of this paper to the literature is twofold. First, since a positive rate of growth at the level of economic activity can be considered as the normal scenario in modern economies due to both population and technological growth, it proposes a new non‐parametric algorithm for the detection and dating of economic acceleration periods, trend or normal growth periods, and economic recessions. Second, it uses an ordered probit framework for the estimation and forecasting of these three business cycle phases, applying an automatized model selection approach using monthly macroeconomic and financial data on the German economy. The empirical results show that this approach has superior out‐of‐sample properties under real‐time conditions compared to alternative probit models specified individually for the prediction of recessions and/or economic accelerations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
62.
Rafaela Lacerda Juliane Menezes Luísa Romão 《Cellular and molecular life sciences : CMLS》2017,74(9):1659-1680
The scanning model for eukaryotic mRNA translation initiation states that the small ribosomal subunit, along with initiation factors, binds at the cap structure at the 5′ end of the mRNA and scans the 5′ untranslated region (5′UTR) until an initiation codon is found. However, under conditions that impair canonical cap-dependent translation, the synthesis of some proteins is kept by alternative mechanisms that are required for cell survival and stress recovery. Alternative modes of translation initiation include cap- and/or scanning-independent mechanisms of ribosomal recruitment. In most cap-independent translation initiation events there is a direct recruitment of the 40S ribosome into a position upstream, or directly at, the initiation codon via a specific internal ribosome entry site (IRES) element in the 5′UTR. Yet, in some cellular mRNAs, a different translation initiation mechanism that is neither cap- nor IRES-dependent seems to occur through a special RNA structure called cap-independent translational enhancer (CITE). Recent evidence uncovered a distinct mechanism through which mRNAs containing N 6-methyladenosine (m6A) residues in their 5′UTR directly bind eukaryotic initiation factor 3 (eIF3) and the 40S ribosomal subunit in order to initiate translation in the absence of the cap-binding proteins. This review focuses on the important role of cap-independent translation mechanisms in human cells and how these alternative mechanisms can either act individually or cooperate with other cis-acting RNA regulons to orchestrate specific translational responses triggered upon several cellular stress states, and diseases such as cancer. Elucidation of these non-canonical mechanisms reveals the complexity of translational control and points out their potential as prospective novel therapeutic targets. 相似文献
63.
S. A. Catanzaro-Guimarães N. Alle E. S. Lopes 《Cellular and molecular life sciences : CMLS》1971,27(12):1400-1401
Résumé Utilisant la méthode cytophotométrique on a observé l'accroissement du glycogène et la réduction de ARN dans le foie de souris soumises au traitement toxique par l'uréthane. 相似文献
64.
Zusammenfassung Werden Lunge und Milz von Yoshida-Sarkomaratten bereits fünf Tage nach der Tumortransplantation entnommen und in normale Ratten implantiert, so zeigt der Umstand, dass sich aus diesen Organen Tumoren entwickeln,in situ belassen aber keine Metastasenknötchen bilden, dass dies auf andere Bedingungen als solche, die mit der Lebensfähigkeit der Zellen zusammenhängen, zurückzuführen ist. 相似文献
65.
M. C. Risueño G. Giménez-Martín J. F. López-Sáez 《Cellular and molecular life sciences : CMLS》1965,21(11):627-628
Résumé Il existen un certain rapport entre la chromatine et des petites invaginations de la membrane nucléaire. Nous estimons que la charge positive de la membrane et la charge négative des chromosomes peut être la cause inductrice. 相似文献
66.
Riassunto Viene descritto un metodo che consente di isolare una buona quantità di linfociti, completamente privi di eritrociti e di piastrine. Il metodo é basato sull'azione emolitica del NH4Cl e sulla ritensione dei granulociti e delle piastrine ad opera del cotone. Questo metodo è risultato molto soddisfacente anche per isolare le cellule di tipo mielocitario dai granulociti dal sangue di pasienti con leucemia mieloide cronica. 相似文献
67.
Males of Cavernocypris subterranea were found for the first time in an Idaho spring. The bisexual form is described on soft body parts and valves. The genus Cavernocypris now includes 2 bisexual and 1 parthenogenteic species. 相似文献
68.
69.
The following species of the fly genus Lispe are redescribed: L. albitarsis (Stein, 1898), L. latana Snyder, 1949, L. levis (Stein, 1911), L. lisarba Snyder, 1949, L. nasoni (Stein, 1898), L. serotina Wulp, 1896, L. setuligera (Stein, 1911) and L. vilis (Stein, 1911). Additionally, a new diagnosis is proposed for L. rufitibialis Macquart, 1843, and in order to fix the identity of the name the lectotype is designated. To facilitate species identification, a pictorial key for the species of Lispe in the Neotropical region and distribution maps are presented, together with the first published illustrations of the male terminalia of L. latana, L. levis and L. lisarba, and the female of L. lisarba. 相似文献
70.
Marília Guimarães Pinheiro Luis Ricardo de Figueiredo Luciana Oranges Cezarino Dante Pinheiro Martinelli 《Systemic Practice and Action Research》2006,19(5):429-440
The aim of this paper is to apply a systemic methodology to analyse the concept of info-inclusion which can guide strategic actions of institutions within civil society and within several levels of government. The paper provides a plan of action that, integrated with other tools, aims at fighting the technological and social gap. We apply Soft System Methodology (SSM), because it provides a holistic approach to info-exclusion. SSM is often used to analyse and resolve problems in complex social studies such as info-exclusion. An info-exclusion reduction project, developed by a university in the country region of Sao Paulo will be provided as a case study. This project is one of the several Brazilian initiatives to solve the problem of limited access to information technology tools. We start by contextualising info-exclusion in Brazil and follow with a review of SSM. We then introduce the concept of info-inclusion and apply SSM to it. We end with a discussion of the results obtained and with some suggestions for action and possible improvements. 相似文献