Efficacy of different protein descriptors in predicting protein functional families

10.1186/1471-2105-8-300BMC Bioinformatics8-BBMI

On dominant contractions and a generalization of the zero-two law

Zaharopol proved the following result: let T,S:L^1(X,{\cf},\m)\to L^1(X,{\cf},\m) be two positive contractions such that $T\leq S$. If $\|S-T\|<1$ then $\|S^n-T^n\|<1$ for all n\in\bn. In the present paper we generalize this result to multi-parameter contractions acting on $L^1$. As an application of that result we prove a generalization of the "zero-two" law.Comment: 10 page

Laser pose estimation and tracking using fuzzy extended information filtering for an autonomous mobile robot

This paper presents methodologies and techniques for posture estimation and tracking of an autonomous mobile robot (AMR) using a laser scanner with at least three retro-reflectors. A three-point laser triangulation method is presented to find an initial posture of the robot and then a fuzzy extended information filtering (FEIF) method is used to improve the accuracy of the robot's posture estimation. With the odometric information from the driving wheels, a FEIF-based posture tracking algorithm is proposed to continuously keep trace of the robot's posture at slow speeds. Simulation and experimental results are conducted to show the efficacy and usefulness of the proposed methods

Photoresponsive and Ultraviolet to Visible-Light Range Photocatalytic Properties of ZnO:Sb Nanowires

100學年度研究獎補助論文[[abstract]]Zinc oxide (ZnO) doped antimony (Sb) nanowires have been synthesized for improving ultraviolet sensing and photocatalytic properties. Upon illumination by UV light (365nm , 2.33mWcm−2 ), the photoelectric current of the ZnO:Sb nanowires exhibited a rapid photoresponse as compared to that of the ZnO nanowires. A highest ratio of photocurrent to dark current of around 48.8-fold was achieved in the as-synthesized ZnO:Sb nanowires. A UV-visible spectrophotometer was used to investigate the absorbance spectrum of the ZnO:Sb nanowires, which exhibited a high absorbance ratio with redshift effect in contrast to that of the ZnO nanowires. Visible-light photocatalysis and UV photoresponsive properties of the ZnO:Sb nanowires are superior to those of the ZnO nanowires.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子

Patient pathways of tuberculosis care-seeking and treatment: an individual-level analysis of National Health Insurance data in Taiwan

Introduction Patients with tuberculosis (TB) often experience difficulties in accessing diagnosis and treatment. Patient pathway analysis identifies mismatches between TB patient care-seeking patterns and service coverage, but to date, studies have only employed cross-sectional aggregate data. Methods We developed an algorithmic approach to analyse and interpret patient-level routine data on healthcare use and to construct patients’ pathways from initial care-seeking to treatment outcome. We applied this to patients with TB in a simple random sample of one million patients’ records in the Taiwan National Health Insurance database. We analysed heterogeneity in pathway patterns, delays, service coverage and patient flows between different health system levels. Results We constructed 7255 pathways for 6258 patients. Patients most commonly initially sought care at the primary clinic level, where the capacity for diagnosing TB patients was 12%, before eventually initiating treatment at higher levels. Patient pathways are extremely heterogeneous prior to diagnosis, with the 10% most complex pathways accounting for 48% of all clinical encounters, and 55% of those pathways yet to initiate treatment after a year. Extended consideration of alternative diagnoses was more common for patients aged 65 years or older and for patients with chronic lung disease. Conclusion Our study demonstrates that longitudinal analysis of routine individual-level healthcare data can be used to generate a detailed picture of TB care-seeking pathways. This allows an understanding of several temporal aspects of care pathways, including lead times to care and the variability in patient pathways

Multisensor 3D posture determination of a mobile robot using inertial and ultrasonic sensors

This paper presents methodologies and techniques for fusing inertial and ultrasonic sensors to estimate the current posture of a mobile robot navigating over indoor uneven terrain. This new type of pose tracking system is developed by means of fusing an inertial navigation subsystem (INS) and an ultrasonic localization subsystem. Extended Kalman filtering (EKF)-based algorithm for integrating both the subsystems is proposed to obtain reliable attitude and position estimates of the vehicle and to eliminate the accumulation errors caused by wheel slippage and surface roughness. Experimental results are conducted to illustrate feasibility and effectiveness of the proposed system and method

Increasing levels of circulating Th17 cells and interleukin-17 in rheumatoid arthritis patients with an inadequate response to anti-TNF-α therapy

Introduction: The objective of this study was to investigate the effects of tumor necrosis factor (TNF)-alpha inhibitors on circulating T helper-type 17 (Th17) cells and Th17-related cytokines in patients with rheumatoid arthritis (RA). Methods: The frequencies of circulating Th17 cells and serum levels of Th17-related cytokines were determined using flow cytometry analysis and ELISA, respectively, in 48 RA patients both before (baseline) and six months after anti-TNF-alpha therapy. Therapeutic response was evaluated using European League Against Rheumatism (EULAR) response criteria. Results: Significantly higher baseline frequencies of circulating Th17 cells and serum levels of interleukin (IL)-6, IL17, IL-21, IL-23 and TNF-alpha were observed in active RA patients than in 12 healthy controls (all P < 0.001). After anti-TNF-alpha therapy, 36 patients (75%) were EULAR responders (20 good responders and 16 moderate responders) and 12 (25.0%) were non-responders. The mean levels of circulating Th17 cells and IL-17 significantly decreased (1.13% vs. 0.79%; 43.1 pg/ml vs. 27.8 pg/ml; respectively, both P < 0.001) in parallel with clinical remission in responders. Levels of IL-6, IL-21, IL-23 and TNF-alpha were significantly decreased after anti-TNF-alpha therapy in responders. In contrast, the mean levels of circulating Th17 cells and IL-17 significantly increased after anti-TNF-alpha therapy (2.94% vs. 4.23%; 92.1 pg/ml vs. 148.6 pg/ml; respectively, both P < 0.05) in non-responders. Logistic regression analysis identified a high baseline level of IL-17 as a significant predictor of poor therapeutic response. Conclusions: The beneficial effect of anti-TNF-alpha therapy might involve a decrease in Th17-related cytokines in responders, whereas rising levels of circulating Th17-cells and IL-17 were observed in patients with an inadequate response to anti-TNF-alpha therapy

Understorey plant community and light availability in conifer plantations and natural hardwood forests in Taiwan

Questions: What are the effects of replacing mixed species natural forests with Cryptomeria japonica plantations on understorey plant functional and species diversity? What is the role of the understorey light environment in determining understorey diversity and community in the two types of forest? Location: Subtropical northeast Taiwan. Methods: We examined light environments using hemispherical photography, and diversity and composition of understorey plants of a 35‐yr C. japonica plantation and an adjacent natural hardwood forest. Results: Understorey plant species richness was similar in the two forests, but the communities were different; only 18 of the 91 recorded understorey plant species occurred in both forests. Relative abundance of plants among different functional groups differed between the two forests. Relative numbers of shade‐tolerant and shade‐intolerant seedling individuals were also different between the two forest types with only one shade‐intolerant seedling in the plantation compared to 23 seedlings belonging to two species in the natural forest. In the natural forest 11 species of tree seedling were found, while in the plantation only five were found, and the seedling density was only one third of that in the natural forest. Across plots in both forests, understorey plant richness and diversity were negatively correlated with direct sunlight but not indirect sunlight, possibly because direct light plays a more important role in understorey plant growth. Conclusions: We report lower species and functional diversity and higher light availability in a natural hardwood forest than an adjacent 30‐yr C. japonica plantation, possibly due to the increased dominance of shade‐intolerant species associated with higher light availability. To maintain plant diversity, management efforts must be made to prevent localized losses of shade‐adapted understorey plants

Mutational analysis of feedback inhibition and catalytic sites of prephenate dehydratase from Corynebacterium glutamicum

Prephenate dehydratase is a key regulatory enzyme in the phenylalanine-specific pathway of Corynebacterium glutamicum. PCR-based random mutagenesis and functional complementation were used to screen for m-fluorophenylalanine (mFP)-resistant mutants. Comparison of the amino acid sequence of the mutant prephenate dehydratases indicated that Ser-99 plays a role in the feedback regulation of the enzyme. When Ser-99 of the wild-type enzyme was replaced by Met, the specific activity of the mutant enzyme was 30% lower than that of the wild-type. The Ser99Met mutant was active in the presence of 50 muM phenylalanine, whereas the wild-type enzyme was not. The functional roles of the eight conserved residues of prephenate dehydratase were investigated by site-directed mutagenesis. Glu64Asp substitution reduced enzyme activity by 15%, with a 4.5- and 1.7-fold increase in K-m and k(cat) values, respectively. Replacement of Thr-183 by either Ala or Tyr resulted in a complete loss of enzyme activity. Substitution of Arg-184 with Leu resulted in a 50% decrease of enzyme activity. The specific activity for Phe185Tyr was more than 96% lower than that of the wild-type, and the K-m value was 26-fold higher. Alterations in the conserved Asp-76, Glu-89, His-115, and Arg-236 residues did not cause a significant change in the K-m and k(cat) values. These results indicated that Glu-64, Thr-183, Arg-184, and Phe-185 residues might be involved in substrate binding and/or catalytic activity

Branchial FXYD protein expression in response to salinity change and its interaction with Na+/K+-ATPase of the euryhaline teleost Tetraodon nigroviridis

Na+/K+-ATPase (NKA) is a ubiquitous membrane-bound protein crucial for teleost osmoregulation. The enzyme is composed of two essential subunits, a catalytic alpha subunit and a glycosylated beta subunit which is responsible for membrane targeting of the enzyme. In mammals, seven FXYD members have been found. FXYD proteins have been identified as the regulatory protein of NKA in mammals and elasmobranchs, it is thus interesting to examine the expression and functions of FXYD protein in the euryhaline teleosts with salinity-dependent changes of gill NKA activity. The present study investigated the expression and distribution of the FXYD protein in gills of seawater (SW)- or freshwater (FW)-acclimated euryhaline pufferfish (Tetraodon nigroviridis). The full-length pufferfish FXYD gene (pFXYD) was confirmed by RT-PCR. pFXYD was found to be expressed in many organs including gills of both SW and FW pufferfish. pFXYD mRNA abundance in gills, determined by real-time PCR, was significantly higher in FW fish than in SW fish. An antiserum raised against a partial amino acid sequence of pFXYD was used for the immunoblots of gill homogenates and a major band at 13 kDa was detected. The relative amounts of pFXYD protein and mRNA in gills of SW and FW pufferfish were identical, but opposite to the expression levels of NKA. Immunofluorescent staining of frozen sections demonstrated that pFXYD was colocalized to NKA-immunoreactive cells in the gill filaments. In addition, interaction between pFXYD and NKA was demonstrated by co-immunoprecipitation. Taken together, salinity-dependent expression of pFXYD protein and NKA, as well as the evidence for their colocalization and interaction in pufferfish gills suggested that pFXYD regulates NKA activity in gills of euryhaline teleosts upon salinity challenge