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This paper introduces a simple and easy to implement procedure to test for changes in persistence. The time‐varying parameter that characterizes persistence changes under the alternative hypothesis is approximated by a parsimonious cosine function. The new test is the minimum of a t‐statistic computed from a test regression that considers a set of reasonable values for a frequency term that is used to evaluate the time‐varying properties of persistence. The asymptotic distributions of the new tests are derived and critical values are provided. An in‐depth Monte Carlo analysis shows that the new procedure has important power gains when compared to the local Generalized Least Squares (GLS) de‐trended Dickey–Fuller type tests under various data generating processes with persistence changes. Moreover, an empirical application to OECD countries’ inflation shows that for most series analysed persistence was high in the first half of the sample and subsequently decreased. These results conform with modern macroeconomic theories that point to changes in inflation dynamics in the early 1980s and also with recent empirical evidence against the I(1)−I(0) dichotomy.

Root-knot nematodes (RKNs), particularly Meloidogyne incognita, are among the most damaging and prevalent agricultural pathogens due to their ability to infect roots of almost all crops. The best strategy for their control is through the use of resistant cultivars. However, laborious phenotyping procedures make it difficult to assess nematode resistance in breeding programs. For common bean, this task is especially challenging because little has been done to discover resistance genes or markers to assist selection. We performed genome-wide association studies and quantitative trait loci mapping to explore the genetic architecture and genomic regions underlying the resistance to M. incognita and to identify candidate resistance genes. Phenotypic data were collected by a high-throughput assay, and the number of egg masses and the root-galling index were evaluated. Complex genetic architecture and independent genomic regions were associated with each trait. Single nucleotide polymorphisms on chromosomes Pv06, Pv07, Pv08, and Pv11 were associated with the number of egg masses, and SNPs on Pv01, Pv02, Pv05, and Pv10 were associated with root-galling. A total of 216 candidate genes were identified, including 14 resistance gene analogs and five differentially expressed in a previous RNA sequencing analysis. Histochemical analysis indicated that reactive oxygen species might play a role in the resistance response. Our findings open new perspectives to improve selection efficiency for RKN resistance, and the candidate genes are valuable targets for functional investigation and gene editing approaches.

We investigate the implications that temporally aggregating, either by average sampling or systematic (skip) sampling, a seasonal process has on the integration properties of the resulting series at both the zero and seasonal frequencies. Our results extend the existing literature in three ways. First, they demonstrate the implications of temporal aggregation for a general sea- sonally integrated process with S seasons. Second, rather than only considering the aggregation of seasonal processes with exact unit roots at some or all of the zero and seasonal frequen- cies, we consider the case where these roots are local-to-unity such that the original series is near-integrated at some or all of the zero and seasonal frequencies. These results show, among other things, that systematic sampling, although not average sampling, can impact on the non- seasonal unit root properties of the data; for example, even where an exact zero frequency unit root holds in the original data it need not necessarily hold in the systematically sampled data. Moreover, the systematically sampled data could be near-integrated at the zero frequency even where the original data is not. Third, the implications of aggregation on the deterministic kernel of the series are explored.

Convincing evidence indicates that advanced glycation end-products and danger-associated protein S100B play a role in Parkinson's disease (PD). These agents operate through the receptor for advanced glycation end-products (RAGE), which displays distinct isoforms playing protective/deleterious effects. However, the nature of RAGE variants has been overlooked in PD studies. Hence, we attempted to characterize RAGE regulation in early stages of PD striatal pathology. A neurotoxin-based rodent model of PD was used in this study, through administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to C57BL/6 mice. Animals were killed 6 h post-MPTP to assess S100B/RAGE contents (RT-qPCR, ELISA) and RAGE isoform density (WB) and cellular distribution (immunohistochemistry). Dopaminergic and gliotic status were also mapped (HPLC-ED, WB, immunohistochemistry). At this preliminary stage of MPTP-induced PD in mice, RAGE inhibitory isoforms were increased whereas full-length RAGE was not affected. This putative cytoprotective RAGE phenotype paired an inflammatory and pro-oxidant setting fueling DAergic denervation. Increased RAGE inhibitory variants occur in astrocytes showing higher S100B density but no overt signs of hypertrophy or NF-κB activation, a canonical effector of RAGE. These findings expand our understanding of the toxic effect of MPTP on striatum and offer first in vivo evidence of RAGE being a responder in early stages of astrogliosis dynamics, supporting a protective rather tissue-destructive phenotype of RAGE in the initial phase of PD degeneration. These data lay the groundwork for future studies on the relevance of astrocytic RAGE in DAergic neuroprotection strategies. We report increased antagonistic RAGE variants paralleling S100B up-regulation in early stages of MPTP-induced astrogliosis dynamics . We propose that selective RAGE regulation reflects a self-protective mechanism to maintain low levels of RAGE ligands , preventing long-term inflammation and oxidative stress arising from sustained ligands/flRAGE activation . Understanding loss of RAGE protective response to stress may provide new therapeutic options to halt or slow down dopaminergic axonopathy and, ultimately, neuronal death .

BACKGROUND: It is important to assess young children's perceived Fundamental Movement Skill (FMS) competence in order to examine the role of perceived FMS competence in motivation toward physical activity. Children's perceptions of motor competence may vary according to the culture/country of origin; therefore, it is also important to measure perceptions in different cultural contexts. The purpose was to assess the face validity, internal consistency, test-retest reliability and construct validity of the 12 FMS items in the Pictorial Scale for Perceived Movement Skill Competence for Young Children (PMSC) in a Portuguese sample. METHODS: Two hundred one Portuguese children (girls, n = 112), 5 to 10 years of age (7.6 ± 1.4), participated. All children completed the PMSC once. Ordinal alpha assessed internal consistency. A random subsamples (n = 47) were reassessed one week later to determine test-retest reliability with Bland-Altman method. Children were asked questions after the second administration to determine face validity. Construct validity was assessed on the whole sample with a Bayesian Structural Equation Modelling (BSEM) approach. The hypothesized theoretical model used the 12 items and two hypothesized factors: object control and locomotor skills. RESULTS: The majority of children correctly identified the skills and could understand most of the pictures. Test-retest reliability analysis was good, with an agreement ration between 0.99 and 1.02. Ordinal alpha values ranged from acceptable (object control 0.73, locomotor 0.68) to good (all FMS 0.81). The hypothesized BSEM model had an adequate fit. CONCLUSIONS: The PMSC can be used to investigate perceptions of children's FMS competence. This instrument can also be satisfactorily used among Portuguese children.

Analysis of the structural connectomes can lead to powerful insights about the brain's organization and damage. However, the accuracy and reproducibility of constructing the structural connectome done with different acquisition and reconstruction techniques is not well defined. In this work, we evaluated the reproducibility of the structural connectome techniques by performing test-retest (same day) and longitudinal studies (after 1 month) as well as analyzing graph-based measures on the data acquired from 22 healthy volunteers (6 subjects were used for the longitudinal study). We compared connectivity matrices and tract reconstructions obtained with the most typical acquisition schemes used in clinical application: diffusion tensor imaging (DTI), high angular resolution diffusion imaging (HARDI), and diffusion spectrum imaging (DSI). We observed that all techniques showed high reproducibility in the test-retest analysis (correlation >.9). However, HARDI was the only technique with low variability (2%) in the longitudinal assessment (1-month interval). The intraclass coefficient analysis showed the highest reproducibility for the DTI connectome, however, with more sparse connections than HARDI and DSI. Qualitative (neuroanatomical) assessment of selected tracts confirmed the quantitative results showing that HARDI managed to detect most of the analyzed fiber groups and fanning fibers. In conclusion, we found that HARDI acquisition showed the most balanced trade-off between high reproducibility of the connectome, higher rate of path detection and of fanning fibers, and intermediate acquisition times (10-15 minutes), although at the cost of higher appearance of aberrant fibers.

In this paper, we analyse the impact of persistent cycles on the well-known semi-parametric unit root tests of Phillips and Perron (1988, Biometrika, Vol. 75, pp. 335–346). It is shown, both analytically and through Monte Carlo simulations, that the presence of complex (near) unit roots can severely bias the size properties of these tests. Given the popularity of these tests with applied researchers and their routine presence in most econometric software packages, the results presented in this paper suggest that practitioners should treat the outcomes of these tests with some caution when applied to data which display a strong cyclical component.

In Brazil, as much as 50% of the native tropical savannas and woodlands (known as the Cerrado) have been converted to farmland under intensive agriculture. Land cover change at this scale has important implications for water and energy budgets, but at present, these implications are poorly understood. A promising new technology for elucidating these relationships at large scales is remote sensing; but results obtained by this method need to be verified with ground-based measurements. For this study, we used remote sensing to estimate changes in energy balance and evapotranspiration (ET) in Sao Paulo State following conversion of native Cerrado woodlands to cultivated land for sugar cane and eucalyptus. We applied the surface energy balance algorithm for land (SEBAL) to ten TM–Landsat 5 images taken during 2005 at two locations (sugar cane fields and Cerrado woodlands). The SEBAL ET results were compared with ET data obtained via eddy covariance. There was good agreement between the two (R2 = 0·87), with no systematic overestimation or underestimation by SEBAL. Our SEBAL analysis indicated that land cover change causes strong shifts in albedo, land-surface temperature, and vegetation index – all of which affect energy balance and ET. Both the SEBAL and eddy covariance measurements indicate that ET for sugar cane is only about 70% of that for native woodlands. SEBAL estimates found that, for cultivated eucalyptus plantations, ET was about 88% of that for Cerrado forests. Our results indicate that the SEBAL methodology is a reliable tool for estimating energy budgets and ET in Cerrado landscapes and, further, that large-scale conversion of Cerrado woodlands to agricultural land significantly alters energy budgets and ET. Copyright © 2014 John Wiley & Sons, Ltd.

One of the prevalent topics in the economic growth literature is the debate between neoclassical, semi-endogenous, and endogenous growth theories regarding the model that best describes the data. An important part of this discussion can be summarized in three mutually exclusive hypotheses: the \constant trend", the \level shift", and the \slope shift" hypotheses. In this paper we propose the characterization of a country’s economic growth path according to these break hypotheses. We address the problem in two steps. First, the number and timing of trend breaks is determined using new structural change tests that are robust to the presence, or not, of unit roots, surpassing technical and methodological concerns of previous empirical studies. Second, conditional on the estimated number of breaks, break dates, and coecients, a statistical framework is introduced to test for general linear restrictions on the coecients of the suggested linear disjoint broken trend model. We further show how the aforementioned hypotheses, regarding the economic growth path, can be analysed by a test of linear restrictions on the parameters of the breaking trend model. We apply the methodology to historical per capita GDP for an extensive list of countries. The results support the three alternative hypotheses for dierent sets of countries. (JEL C22, F43, O40)

Brush border Myosin Ia (MYO1A) has been shown to be frequently mutated in colorectal tumors with microsatellite instability (MSI) and to have tumor suppressor activity in intestinal tumors. Here, we investigated the frequency of frameshift mutations in the A8 microsatellite in exon 28 of MYO1A in MSI gastric and endometrial tumors and found a high mutation rate in gastric (22/47; 46.8%) but not endometrial (3/48; 6.2%) tumors. Using a regression model, we show that MYO1A mutations are likely to confer a growth advantage to gastric, but not endometrial tumors. The mutant MYO1A(7A) protein was shown to lose its membrane localization in gastric cancer cells and a cycloheximide-chase assay demonstrated that the mutant MYO1A(7A) protein has reduced stability compared to the wild type MYO1A. Frequent MYO1A promoter hypermethylation was also found in gastric tumors. Promoter methylation negatively correlates with MYO1A mRNA expression in a series of 58 non-MSI gastric primary tumors (Pearson's r = -0.46; p = 0.0003) but not in a cohort of 54 non-MSI endometrial tumors and treatment of gastric cancer cells showing high MYO1A promoter methylation with the demethylating agent 5-aza-2'-deoxycytidine, resulted in a significant increase of MYO1A mRNA levels. We found that normal gastric epithelial cells, but not normal endometrial cells, express high levels of MYO1A. Therefore, when considered together, our findings suggest that MYO1A has tumor suppressor activity in the normal gastric epithelium but not in the normal endometrium and inactivation of MYO1A either genetically or epigenetically may confer gastric epithelial cells a growth advantage.

In this paper, we introduce unit root tests for time series with a potential structural break computed from test regressions in which the deterministic components have been recursively adjusted. We present finite sample critical values as well as Monte Carlo results on the size and power performance of the new procedures, and compare these with other available tests in the literature, such as OLS and quasi-differenced based tests (see, for instance, Perron, (1997)Perron and Rodriguez, (2003) and Carrion-i-Silvestre et al. (2009)). The small sample behaviour of the tests is evaluated in a known and an unknown break date context allowing for negligible and non-negligible initial conditions. In the unknown break date case, two break date estimation procedures are considered, one based on the minimum unit root t-statistic and the other based on the minimum sum of squared residuals obtained from a regression on a set of deterministic variables. The size and power performance of the recursive adjustment based procedure in the unknown break date case is encouraging. A further result of this paper relates to the aditional finite sample evidence on the performance of quasi-differenced unit root tests, complementing the results in Perron and Rodriguez (2003).

This article discusses the asymptotic and finite-sample properties of the CUSUM tests for detecting structural breaks in volatility when the data are perturbed with (additive) outliers and/or measurement errors. The special focus is on the parametric and non-parametric tests in Inclan and Tiao (1994) and Kokoszka and Leipus (2000). Whereas the asymptotic distribution of the former can be largely affected, the distribution of the latter remains invariant and renders consistent break-point estimates. In small samples, however, large additive outliers are able to generate sizeable distortions in both tests, which explains some of the contradictory findings in previous literature.

Citation information: Jorge J, Gonzalez-Meijome JM, Queiros A, Fernandes P & Diaz-Rey JA. A comparison of the NCT Reichert R7 with Goldmann applanation tonometry and the Reichert ocular response analyzer. Ophthalmic Physiol Opt 2011, 31, 174–179. doi: 10.1111/j.1475-1313.2010.00817.x Abstract Purpose: The aim of this study was to evaluate the accuracy of intraocular pressure (IOP) values from the new non-contact tonometer (NCT) Reichert R7 by comparing results with those from Goldmann applanation tonometry (GAT) and the Reichert Ocular Response Analyzer (ORA). Other ocular dimensions were assessed to evaluate their potential influence on the IOP values obtained. Methods: Ninety two right eyes from 92 adults aged between 21 and 59 years (mean 34.9 ± 11.7 years) were enrolled in this study. IOP was measured with R7, ORA and GAT. All measurements were taken between 14:00 and 16:00 in the afternoon. Corneal resistance factor (CRF) and corneal hysteresis were measured with the Reichert ORA. The spherical equivalent refractive error was obtained using an open field auto-refractor (WAM5500; Grand Seiko) and corneal curvature, anterior chamber depth, corneal diameter and axial length were assessed with an optical coherence biometer (IOL Master; Zeiss Meditec, CA, USA). Results: The mean values for IOP measurements were 15.20 ± 3.37 mmHg (R7), 13.49 ± 3.55 mmHg (GAT), 15.01 ± 3.38 mmHg (ORA IOPcc) and 14.44 ± 3.47 mmHg (ORA IOPg). With the exception of the CRF (ρ = 0.72 p

The aim of this study was to evaluate the level of agreement of measurements of intraocular pressure (IOP) taken by a rebound tonometer (IOPen ® ), in comparison to a reference Goldmann applanation tonometer (GAT) in a glaucomatous population. Both eyes from 60 patients were assessed with the two tonometers, the induction tonometry was performed first by an experienced optometrist, and the GAT by an ophthalmologist. In this study, statistically significant differences were found when comparing the IOPen ® tonometer with the GAT tonometer (p < 0.001), mean differences were -4.81 ± 4.31 and -4.76 ± 5.76 mmHg (mean ± S.D.) for the right eye and left eye respectively These values represent an underestimation in the present population by the IOPen ® when compared with the GAT. Frequency distribution of differences demonstrated that in more than 71.6% of the measurements the IOP readings differed by more than 3 mmHg between the two tonometers. These results suggest that IOPen ® should be used with great caution in the determination of IOP.

© 2010, American College of Rheumatology, Objective. CD8+ T cells are part of the T cell pool infiltrating the synovium in rheumatoid arthritis (RA). However, their role in the pathogenesis of RA has not been fully delineated. Using the K/BxN mouse model of spontaneous chronic arthritis, which shares many similarities with RA, we studied the potential of CD8 T cell depletion with monoclonal antibodies (mAb) to stop and reverse the progression of experimental arthritis. Methods. CD8+ T cells from the blood and articular infiltrate of K/BxN mice were characterized for cell surface phenotypic markers and for cytokine production. Additionally, mice were treated with specific anti-CD8 mAb (YTS105 and YTS169.4), with and without thymectomy. Results. CD8+ T cells from the peripheral blood and joints of K/BxN mice were mainly CD69+ and CD62L-CD27+ T cells expressing proinflammatory cytokines (interferon-γ [IFNγ], tumor necrosis factor α [TNFα], interleukin-17a [IL-17A], and IL-4), and granzyme B. In mice receiving anti-CD8 mAb, the arthritis score improved 5 days after treatment. Recovery of the CD8+ T cells was associated with a new increase in the arthritis score after 20 days. In thymectomized and anti-CD8 Ab–treated mice, the arthritis score improved permanently. Histologic analysis showed an absence of inflammatory infiltrate in the anti-CD8 mAb–treated mice. In anti-CD8 mAb–treated mice, the serologic levels of TNFα, IFNγ, IL-6, and IL-5 normalized. The levels of the disease-related anti–glucose-6-phosphate isomerase antibodies did not change. Conclusion. These results indicate that synovial activated effector CD8 T cells locally synthesize proinflammatory cytokines (IFNγ, TNFα, IL-17, IL-6) and granzyme B in the arthritic joint, thus playing a pivotal role in maintaining chronic synovitis in the K/BxN mouse model of arthritis., Mr. Raposo’s work was supported by the Instituto do Emprego e Formação Profissional (grant 266/EP/2006) and the Fundação para a Ciência e Tecnologia (grant SFRH/BD/40658/2007). Ms Carvalheiro’s work was supported by the Fundação para a Ciência e Tecnologia (grant SFRH/BD/60467/2009). Dr. Graça’s work was supported by the Fundação para a Ciência e Tecnologia (grant POCI/SAU-MMO/55974/2004). Dr. Souto-Carneiro’s work was supported by a Marie Curie Intra-European Fellowship (LIF-025885) and a EULAR Young Investigator Award.

This study considers relationships among motor coordination (MC), physical fitness (PF) and physical activity (PA) in children followed longitudinally from 6 to 10 years. It is hypothesized that MC is a significant and primary predictor of PA in children. Subjects were 142 girls and 143 boys. Height, weight and skinfolds; PA (Godin-Shephard questionnaire); MC (Korperkoordination Test fur Kinder); and PF (five fitness items) were measured. Hierarchical linear modeling with MC and PF as predictors of PA was used. The retained model indicated that PA at baseline differed significantly between boys (48.3 MET/week) and girls (40.0 MET/week). The interaction of MC and 1 mile run/walk had a positive influence on level of PA. The general trend for a decrease in PA level across years was attenuated or amplified depending on initial level of MC. The estimated rate of decline in PA was negligible for children with higher levels of MC at 6 years, but was augmented by 2.58 and 2.47 units each year, respectively, for children with low and average levels of initial MC. In conclusion MC is an important predictor of PA in children 6-10 years of age.

Data from field experiments conducted in the semiarid climatic conditions of northeast Brazil were used to investigate the energy flux relations and evapotranspiration (ET) of a mango (Mangifera indica L.) orchard. The Bowen ratio-energy balance method was applied during the 1998-1999 fruiting cycles to estimate the energy balance components of the mango orchard, while the FAO Penman-Monteith approach was used for determining the reference evapotranspiration (ET o ). Results indicated that latent heat flux density (λE) could be obtained, with reasonable precision, as a function of measured net radiation flux density (R n ). The percentage of R n used as BE was higher for the fruit growth and fruit maturation phenological stages, and lower for the flowering and fruit fall stages. For both field campaigns, BE was found to be the major component of energy balance, comprising >70% of the available energy. Soil heat flux was always the smaller component, comprising

Purpose: To assess the accuracy and repeatability of central corneal thickness (CCT) measurements taken with a new portable ultrasound (US) pachymeter.Methods: Central thickness measurements were taken with a portable pachymeter (SP-100 Handy; Tomey, Nagoya, Japan) and a conventional US pachymeter (Nidek UP-1000; Nidek Technologies, Gamagori, Japan) from 57 right corneas of 57 young adults (19 males, 38 females) aged 18-44 years (mean +/- S.D., 22.95 +/- 3.92). Three repeated measures were obtained and then compared to obtain the repeatability of each instrument and the agreement between the pachymeters. The three readings taken with the portable pachymeter were compared against each other in order to evaluate intra-session repeatability and bias of each individual measurement with respect to the mean of three.Results: Mean values of CCT were 537 +/- 35 mu m for conventional and 534 +/- 35 mu m for the new portable pachymeter. A high agreement was found between the two instruments (mean difference = 2.58 mu m; 95% CI 1.41-3.75 mu m) with only two eyes presenting differences larger than +/- 8.6 mu m which represents 95% CI in the Bland-Altman plots which represents 1.6% of the mean CCT. The first reading taken showed the highest agreement with the mean value for the portable pachymeter.Conclusions: The instrument tested in this study is able to take reliable measurements of corneal thickness even if a single reading is considered. Intra-session repeatability was very high, as was also the agreement between the average of three readings taken with the two US pachymeters., (undefined)

The aim of this study was to evaluate the accuracy of measurement of intraocular pressure (IOP) using a new induction/impact rebound tonometer (ICare) in comparison with the Goldmann applanation tonometer (AT). The left eyes of 46 university students were assessed with the two tonometers, with induction tonometry being performed first. The ICare was handled by an optometrist and the Goldmann tonometer by an ophthalmologist. In this study, statistically significant differences were found when comparing the ICare rebound tonometer with applanation tonometry (AT) (p < 0.05). The mean difference between the two tonometers was 1.34 +/- 2.03 mmHg (mean +/- S.D.) and the 95% limits of agreement were +/-3.98 mmHg. A frequency distribution of the differences demonstrated that in more than 80% of cases the IOP readings differed by

To assess the accuracy and repeatability of central corneal thickness (CCT) measurements taken with a new portable ultrasound (US) pachymeter. Methods: Central thickness measurements were taken with a portable pachymeter (SP-100 Handy;Tomey, Nagoya, Japan) and a conventional US pachymeter (Nidek UP-1000; Nidek Technologies, Gamagori, Japan) from 57 right corneas of 57 young adults (19 males, 38 females) aged 18–44 years (mean ± S.D., 22.95 ± 3.92). Three repeated measures were obtained and then compared to obtain the repeatability of each instrument and the agreement between the pachymeters. The three readings taken with the portable pachymeter were compared against each other in order to evaluate intra-session repeatability and bias of each individual measurement with respect to the mean of three. Results: Mean values of CCT were 537 ± 35 micron for conventional and 534 ± 35 micron for the new portable pachymeter. A high agreement was found between the two instruments mean difference = 2.58 micron; 95% CI 1.41–3.75 micron) with only two eyes presenting differences larger than ± 8.6 micron which represents 95% CI in the Bland-Altman plots which represents 1.6% of the mean CCT. The first reading taken showed the highest agreement with the mean value for the portable pachymeter. Conclusions: The instrument tested in this study is able to take reliable measurements of corneal thickness even if a single reading is considered. Intra-session repeatability was very high, as was also the agreement between the average of three readings taken with the two US pachymeters.