Deterministic Seasonality in Dickey-Fuller Tests: Should We Care?

This paper investigates the properties of Dickey-Fuller tests for seasonally unadjusted quarterly data when deterministic seasonality is present but it is neglected in the test regression. While for the random walk case the answer is straightforward, an extensive Monte Carlo study has to be performed for more realistic processes and testing strategies. The most important conclusion is that the common perception that deterministic seasonality has nothing to do with the long-run properties of the data is incorrect. Further numerical evidence on the shortcomings of the general-to-specific t-sig lag selection method is also presented.unit root; Dickey-Fuller tests; similar tests; seasonality; Monte Carlo

The Order of Integration for Quarterly Macroeconomic Time series: a Simple Testing Strategy

Besides introducing a simple and intuitive definition for the order of integration of quarterly time series, this paper also presents a simple testing strategy to determine that order for the case of macroeconomic data. A simulation study shows that much more attention should be devoted to the practical issue of selecting the maximum admissible order of integration. In fact, it is shown that when that order is too high, one may get (spurious) evidence for an excessive number of unit roots, resulting in an overdifferenced series.

The expectations hypothesis of the term structure: some empirical evidence for Portugal

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous evidence for other countries. The empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. In the single equation framework, the implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected

The Expectations Hypothesis of the Term Structure: Some Empirical Evidence for Portugal

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous evidence for other countries. The empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. In the single equation framework, the implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected, even for the more stable period which emerged in the middle nineties.term structure of interest rates; expectations hypothesis; hypothesis testing; cointegration; Portugal

The expectations hypothesis of the term structure: some empirical evidence for Portugal

The purpose of this paper is to test the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results obtained support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous evidence for other countries. The empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. In the single equation framework, the implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected.term structure of interest rates; expectations hypothesis; hypothesis testing; cointegration; Portugal

The Behavior of HEGY Tests for Quarterly Time Series with Seasonal Mean Shifts

This paper studies the behavior of the HEGY statistics for quarterly data, for seasonal autoregressive unit roots, when the analyzed time series is deterministic seasonal stationary but exhibits a change in the seasonal pattern. As a by-product we analyze also the HEGY test for the nonseasonal unit root, the data generation process being trend stationary too. Our results show that when the break magnitudes are finite the HEGY test statistics are not asymptotically biased towards the non-rejection of the seasonal and nonseasonal unit root hypotheses. However, the finite sample power properties may be substancially affected, the behavior of the tests depending on the type of the break. Hence, our results are also useful to understand and to predict this behavior under several circumstances.seasonality; unit roots; strctural breaks; HEGY tests

Short and long run tests of the expectations hypothesis: the Portuguese case

The purpose of this paper is to test both short- and long-run implications of the (rational) expectations hypothesis of the term structure of interest rates using Portuguese data for the interbank money market. The results support only a very weak, long-run or "asymptotic" version of the hypothesis, and broadly agree with previous (but separate) evidence for other countries. Empirical evidence supports the cointegration of Portuguese rates and the "puzzle" well known in the literature: although its forecasts of future short-term rates are in the correct direction, the spread between longer and shorter rates fails to forecast future longer rates. Further short-run implications of the hypothesis in terms of the predictive ability of the spread are also clearly rejected, even for the more stable period which emerged in the middle nineties.Term structure; Expectations hypothesis; Hypothesis testing; Structural breaks; Portugal

Biotechnological applications of mammalian odorant-binding proteins

The olfactory system of mammals allows the detection and discrimination of thousands of odors from the environment. In mammals, odorant-binding proteins (OBPs) are considered responsible to carry odorant molecules across the aqueous nasal mucus to the olfactory receptors (ORs). The three-dimensional structure of these proteins presents eight antiparallel ?-sheets and a short ?-helical segment close to the C terminus, typical of the lipocalins family. The great ability of OBPs to bind differentiated ligand molecules has driven the research to understand the mechanisms underlying the OBP function in nature and the development of advanced biotechnological applications. This review describes the role of mammalian OBPs in the olfactory perception, highlighting the influence of several key parameters (amino acids, temperature, ionic strength, and pH) in the formation of the OBP/ligand complex. The information from the literature regarding OBP structure, affinity, the strength of binding, and stability inspiring the development of several applications herein detailed.This study was financially supported by the Portuguese Foundation for Science and Technology (Fundac¸~ao para a Ciencia e a Tecnologia) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation [NORTE-01-0145-FEDER-000004] funded by European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. F.G. thanks Fundac~ao para a Ci^ encia e a Tecnologia for their funding [SFRH/BD/114684/2016].info:eu-repo/semantics/publishedVersio

Release of fragrances from cotton functionalized with carbohydrate-binding module proteins

Perspiration as a response to daily activity and physical exercise results in unpleasant odors that cause social unrest and embarrassment. To tackle it, functional textiles incorporating fragrances could be an effective clothing deodorizing product. This work presents two strategies for the release of -citronellol from functionalized cotton with carbohydrate-binding module (CBM)-based complexes (OBP::GQ20::CBM/-citronellolapproach 1 and CBM::GQ20::SP-DS3-liposome/-citronellolapproach 2). CBM from Cellulomonas fimi was fused with the odorant-binding protein (OBP::GQ20::CBM) and with an anchor peptide with affinity to the liposome membrane (CBM::GQ20::SP-DS3). In approach 1, OBP fusion protein served as a fragrance container, whereas in approach 2, the fragrance was loaded into liposomes with a higher cargo capacity. The two strategies showed a differentiated -citronellol release profile triggered by an acidic sweat solution. OBP::GQ20::CBM complex revealed a fast release (31.9% and 25.8% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively), while the CBM::GQ20::SP-DS3-liposome complex demonstrated a slower and controlled release (5.9% and 10.5% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively). Both strategies revealed high potential for textile functionalization aimed at controlled release of fragrances. The OBP::GQ20::CBM/-citronellol complex is ideal for applications requiring fast release of a high amount of fragrance, whereas the CBM::GQ20::SP-DS3-liposome/-citronellol complex is more suitable for prolonged and controlled release of a lower amount of -citronellol.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. F.G. and C.S. thanks FCT for their funding (SFRH/BD/114684/2016; SFRH/IF/00186/2015).info:eu-repo/semantics/publishedVersio

Chemically modified lipase from Thermomyces lanuginosus with enhanced esterification and transesterification activities - Front cover

The Front Cover shows a super catalyst (SC) lipase obtained through chemical modification for the production of several industrial products like ester-based compounds. In their Full Paper, J. Noro etal. studied the impact of the chemical modification of lipase from Thermomyces lanuginosus with dodecyl aldehyde, on its esterification and transesterification activity. The enzyme, modified with four dodecyl chains, showed an outstanding improvement of the catalytic performance for both reactions, comparing to the unmodified lipase. The most notorious results were achieved when longer chain-length alcohols were used for the transesterification of p-nitrophenyl palmitate and for the esterification of oleic acid. The novel enzyme modification strategy developed by the authors, resulted in the transformation of a super catalyst, with countless fields of applications, including the production of ester-based products for cosmetic and medical fields. More information can be found in the Full Paper by J. Noro etal.info:eu-repo/semantics/publishedVersio