Temporomandibular Joint Disorders in Patients with Rheumatoid Arthritis

BackgroundTemporomandibular joint disorders (TMD) are not uncommon in patients with rheumatoid arthritis (RA). However, the extent of involvement and its clinical relevance have not been well characterized. This study evaluated the correlation between the severity of RA-related TMD and RA, as well as determined the potential predictors for early identification and management of TMD in RA patients.MethodsWe sequentially recruited 56 adult RA patients from our Arthritis Clinic. TMD and RA were surveyed, clinically by questionnaires and physical examinations, and radiologically by tomography in TMD and conventional radiography in RA. The patients were stratified into no, mild and severe TMD groups according to the physical and tomographic examinations. The correlation of the severity of TMD and RA were evaluated. The relative importance of relevant predictors of severe TMD was analyzed by a logistic regression model.ResultsPhysical and radiologic temporomandibular joint abnormalities were found to be highly prevalent (85.7% and 74.5%) in these patients, and the occurrence increased to as much as 92.9% when the 2 data sets were combined. More than half of the patients had severe TMD presenting with debilitating symptoms or with a significant degree of bony destruction. The severity of TMD was variably correlated with RA severity. The score of hand-joint space narrowing was found to be the most influential predictor of severe TMD by logistic regression analysis.ConclusionThere was a high prevalence of TMD in RA patients. The severity of TMD variably correlated with RA severity. Clinically, a high score of hand-joint space narrowing may serve as an early indicator of RA patients at risk of severe TMD. This may facilitate early management and prevent the functional impairment of the temporomandibular joint

Complementarities of R&D strategies on innovation performance: Evidence from Taiwanese manufacturing firms

This paper aims to empirically test the R&D complementarities among three alternative R&D strategies, namely, internal R&D, external R&D and cooperative R&D, under different measures of innovation output. Using a firm-level data set based on the Taiwanese innovation survey (in accordance with CIS 3) conducted in 2003, we are able to compare the R&D activities in this newly-industrialized country with other developed countries. Additionally, we apply a two-step procedure to reduce the endogeneity problem caused by the firms’ choices of strategies to obtain consistent estimators, which can be regarded as a combined method of adoption and productivity approaches. We show that the results of the estimation for R&D complementarities may be biased upwards or downwards if we do not include selection equations in the empirical models, thereby giving rise to endogeneity problems. Our empirical results generally support the existence of R&D complementarities, while the strength of complementary effects may vary across different measures of innovation output. Moreover, our finding suggests that the complementary relationship between external and cooperative R&D is fairly robust to various model specifications

Do different types of FDI strategies spur productivity and innovation capability growth? Evidence from Taiwanese manufacturing firms

Based on different motivations for engaging in outward FDI, this study divides firms' outward FDI into five types: non-FDI, FDI, defensive only outward FDI, expansive only outward FDI, and both defensive & expansive outward FDI simultaneously, and proposes four hypotheses to evaluate their relative strength in terms of firm productivity and innovation capability. The propensity score matching estimator based on a uniquely compiled Taiwanese manufacturing data set shows that, as firms engage in outward FDI, they have higher productivity growth rates compared to non-FDI firms. As for the further disengagement of the impacts of outward FDI, our empirical results indicate that expansive outward FDI tends to strengthen firms' productivity growth, while such a growth-boosting effect is not statistically significant for defensive outward FDI. Moreover, as far as firms undertaking defensive & expansive outward FDI simultaneously are concerned, we also find a positive and significant impact of outward FDI on productivity growth, but the effect is not as large as that for firms engaging solely in expansive outward FDI. This may imply that defensive outward FDI has some adverse effects on firms' productivity growth. As firm performance is measured by innovation growth, the average treatment effects are all significantly positive regardless of the type of outward FDI strategies. Nevertheless, engaging in defensive outward FDI is less advantageous to innovation growth than the expansionary outward FDI, as well as to defensive & expansive outward FDI simultaneously

(E)-N-[2-(Benzyl­iminometh­yl)phen­yl]-2,6-diisopropyl­aniline

The mol­ecular conformation of the title compound, C26H30N2, is reinforced by an intra­molecular N—H⋯N hydrogen bond, resulting in an almost planar [mean deviation of 0.023 (2) Å] S(6) ring. The dihedral angles between the central benzene ring and the terminal unsubstituted and substituted aromatic rings are 64.45 (9) and 89.40 (8)°, respectively

VI-Band Follow-Up Observations of Ultra-Long-Period Cepheid Candidates in M31

The ultra-long period Cepheids (ULPCs) are classical Cepheids with pulsation periods exceeding $\approx 80$ days. The intrinsic brightness of ULPCs are ~1 to ~3 mag brighter than their shorter period counterparts. This makes them attractive in future distance scale work to derive distances beyond the limit set by the shorter period Cepheids. We have initiated a program to search for ULPCs in M31, using the single-band data taken from the Palomar Transient Factory, and identified eight possible candidates. In this work, we presented the VI-band follow-up observations of these eight candidates. Based on our VI-band light curves of these candidates and their locations in the color-magnitude diagram and the Period-Wesenheit diagram, we verify two candidates as being truly ULPCs. The six other candidates are most likely other kinds of long-period variables. With the two confirmed M31 ULPCs, we tested the applicability of ULPCs in distance scale work by deriving the distance modulus of M31. It was found to be $\mu_{M31,ULPC}=24.30\pm0.76$ mag. The large error in the derived distance modulus, together with the large intrinsic dispersion of the Period-Wesenheit (PW) relation and the small number of ULPCs in a given host galaxy, means that the question of the suitability of ULPCs as standard candles is still open. Further work is needed to enlarge the sample of calibrating ULPCs and reduce the intrinsic dispersion of the PW relation before re-considering ULPCs as suitable distance indicators.Comment: 13 pages, with 14 Figures and 4 Tables (one online table). AJ accepte