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The doubly vergent orogen in Taiwan is a relatively young and active arc-continent collision caused by the convergence of Eurasian and Philippine Sea Plates occurring along a complicated seismogenic plate boundary. This study aims to investigate the evolutionary and tectonic features of the retro-wedge, a region contributing to the uplifting and shortening of the Taiwan orogen. Through the utilization of seismic tomographic image and relocated seismicity, we identify three potential seismogenic structures along the convergent plate boundary: the Longitudinal Valley Fault, the Ludao–Lanyu Fault, and the Central Range Fault. A significant discovery in our investigation is a west-dipping backthrust of the Central Range Fault, extending from the north Hualien city to the southeastern offshore at a distance of 300 km. The fault is responsible for the formation of a crustal-scale pop-up structure, contributing to the development of a double vergent orogenic wedge in the retro-wedge. The genesis of the basement-involved backthrust is attributed to the indentation of the exhumed forearc mantle wedge and remnant forearc crust into the Backbone Range during collision. Consequently, the plate boundary exhibits two opposite vergent thrust systems of the Longitudinal Valley Fault–Ludao–Lanyu Fault and Central Range Fault, which evolved during different stages of collision-incipient and mature following the closure of the forearc basin of the North Luzon Trough and Longitudinal Valley, respectively. These findings contribute novel insights into the tectonic framework of the convergent zone and provide valuable constraints for geodynamic models of arc-continent collision. [ABSTRACT FROM AUTHOR]

Background and Objective The present study investigated the association between the RAGE G82S polymorphism, the plasma levels of sRAGE and chronic periodontitis in subjects with and without diabetes mellitus ( DM). Material and Methods A total of 230 patients with DM and 264 non- DM participants were recruited for this study. Genotyping of the RAGE G82S polymorphism was accomplished using polymerase chain reaction-restriction fragment length polymorphism, and associations were analyzed with the chi-squared test and logistic regression analysis. Results In the non- DM group, the chi-squared test showed that the frequency distributions of the G82S polymorphism were significantly different between chronic periodontitis and non- chronic periodontitis subjects (χ2 = 8.39, p = 0.02). A multivariate logistic regression model showed that the (G82S + S82S) genotypes were associated with a significantly increased risk of chronic periodontitis development compared to the G82G genotype (adjusted odds ratio = 2.06, 95% confidence interval: 1.08-4.07). In the DM group, there was no association between the G82S polymorphism and chronic periodontitis development when a multivariate logistic regression was performed. Plasma levels of sRAGE were significantly higher in subjects with the G82G genotype compared to those with the (G82S + S82S) genotypes in both the non- DM (856.6 ± 332.0 vs. 720.4 ± 311.4 pg/ mL, p = 0.003) and DM groups (915.3 ± 497.1 vs. 603.5 ± 298.3 pg/ mL, p < 0.0001). However, there was no difference in plasma sRAGE levels between chronic periodontitis and non- chronic periodontitis subjects in both the DM and non- DM groups. Moreover, when the subjects were further sub-divided by the G82S polymorphism, the difference in plasma levels of sRAGE between chronic periodontitis and non- chronic periodontitis subjects in the DM and non- DM groups remained statistically insignificant. Conclusions The present study revealed that the RAGE G82S polymorphism was associated with chronic periodontitis in the non- DM group but not in the DM group. Our results also showed that the plasma levels of sRAGE were significantly higher in subjects with the RAGE G82G genotype, and this correlation was not affected by the presence of chronic periodontitis in the DM and non- DM groups. [ABSTRACT FROM AUTHOR]

Increasingly detailed studies of out crops of high-pressure rock terranes in combination with rapidly evolving numerical modeling studies have given rise to a number of possible explanations for the processes by which these rocks are exhumed. Imaging actively exhuming high-pressure terranes remains one of the fundamental, but elusive, tasks that could advance the understanding of how these important rocks reach Earth's surface. Seismic tomography along the active arc-continent collision in eastern Taiwan images a high P- and S-wave velocity zone that extends from the shallow subsurface beneath a high-pressure metamorphic terrane to ~50 km depth. We present a petrophysical analysis of this high-velocity zone that indicates the presence of rock types common to high-pressure terranes. The high-velocity zone is seismically active throughout. We determine focal mechanisms for 57 earthquakes, and carry out full waveform modeling on 10; these have double-couple focal mechanisms with a compensated linear vector dipole component up to 20.6%. We suggest that the high-velocity zone comprises an exhuming high-pressure terrane. Focal mechanisms for earthquakes within it indicate that shear faulting dominates in the deformation, but high fluid pressure may also play a role. [ABSTRACT FROM AUTHOR]

In this work, two approaches were employed for estimating the spatiotemporal distribution of seismicity density in Taiwan. With the use of the rate-and-state friction model, a model for short-term forecasting according to the fault-interaction-based rate disturbance due to seismicity was considered. Another long-term forecasting model that involves a smoothing Kernel function is proposed. The application of the models to Taiwan led to good agreement between the model forecast and actual observations. Using an integration of the two approaches, the application was found to be capable of providing a seismicity forecast with a higher accuracy and reliability. To check the stability related to the regression the bandwidth function, the forecasted seismicity rates corresponding to the upper and lower bounds of the 95% confidence intervals are compared. The result shows that deviations within the bandwidth functions had an insignificant impact on forecasting reliability. Besides, insignificant differences in the forecasted rate change were obtained when Aσ was assumed to be between 0.1 and 0.4 bars for the application of the rate-and-state friction model. By considering the maximum Coulomb stress change among the seismogenic depth, the model presents a better forecasting ability than that using any single fixed target depth. The proposed methodology, with verified applicability for seismicity forecasts, could be useful for seismic hazard analyses. [ABSTRACT FROM AUTHOR]

Background and Objective: Single nucleotide polymorphisms are assumed to be associated with the differential production of cytokines. We evaluated gene polymorphisms of interleukin-10 (−592C>A, −819C>T and −1082G>A) and interleukin-12B (+16974) in patients with chronic periodontitis ( n = 145) and generalized aggressive periodontitis ( n = 65) in comparison with healthy controls ( n = 126). Material and Methods: Gene promoter polymorphisms were analyzed by polymerase chain reaction with sequence-specific primers. Genotype and allele frequencies were analyzed using the chi-square test and logistic regression analysis. Results: The interleukin-10 −592 polymorphism showed significant differences among the three groups ( p = 0.0330). The genotype frequencies of the −592 locus between the chronic periodontitis and healthy control groups were significantly different (AC vs. AA: odds ratio = 0.33). The combination ATA/ATA seemed to be associated with susceptibility to generalized aggressive periodontitis ( p = 0.0276). Patients with the composite ATA/ACC were less likely to develop chronic periodontitis ( p = 0.0248). The CC genotype of interleukin-12B (+16974) was related to chronic periodontitis (CC vs. AA, p = 0.0211; CC vs. AA+AC, p = 0.0187). The AC heterozygosity of interleukin-12B was significantly lower in chronic periodontitis vs. healthy controls ( p = 0.0500). Conclusion: The interleukin-10 gene polymorphism at position −592C>A may be associated with a lower risk for development of chronic periodontitis. The interleukin-10 haplotype ATA is associated with generalized aggressive periodontitis. On the other hand, interleukin-12B genetic variants at position +16974 are associated with susceptibility to chronic periodontitis. [ABSTRACT FROM AUTHOR]

Background and Objective: A dramatic difference in the frequencies of the Lys/Arg single nucleotide polymorphism in the lactoferrin genotype between a small population of patients with localized juvenile periodontitis and healthy subjects has been reported. As the single nucleotide polymorphism could be associated with ethnicity, the present study aimed to investigate the association between polymorphisms of the lactoferrin gene and periodontitis. Material and Methods: Sixty-five patients with aggressive periodontitis, 278 with chronic periodontitis and 88 healthy controls were genotyped for the Lys/Arg polymorphism of the lactoferrin gene at position 29 [reference sequence (rs) 1126478] in the N-terminal alpha-helical region. Results: The frequencies of the GG genotype and the G allele were highest in the aggressive periodontitis group, followed by the chronic periodontitis group and then the healthy controls. The frequency of the G allele was significantly higher in aggressive periodontitis and chronic periodontitis groups than in healthy controls ( p = 0.0037 and 0.0212). Although the difference of the GG genotype distribution between subjects with chronic periodontitis and healthy controls did not reach significance, the distribution of genotypes between aggressive periodontitis and healthy controls was significantly different. The association of the gene polymorphism and aggressive periodontitis still existed, even after adjusting for age, gender and smoking status by logistic regression analysis (GG/AG+AA: odds ratio = 2.16, 95% confidence interval = 1.09–4.35, p = 0.0287). After the study, subjects were further stratified by their smoking status; the GG genotype was still significantly associated with the risk of aggressive periodontitis in the nonsmoking group (odds ratio = 2.69, p = 0.018). However, there were no statistical differences between chronic periodontitis vs. healthy controls and aggressive periodontitis vs. healthy controls in the smoking group. Conclusion: The present study revealed that the A/G polymorphism in the lactoferrin gene might be associated with aggressive periodontitis. The A allele might reduce the risk of development of aggressive periodontitis in a Taiwanese population. Our results also support the hypothesis that lactoferrin genetic polymorphisms could play a role in the risk for periodontitis separate from the smoking factor. The functionality of this gene’s polymorphisms has to be further elucidated. [ABSTRACT FROM AUTHOR]

A structural model is developed for the south-central Taiwan fold-and-thrust belt that shows consistency across an array of data types and marks an important step forward in the consideration of geological hazards and risks. Although there is general agreement about the regional scale geology of Taiwan, there are considerable differences in the structural interpretations of its western fold-and-thrust belt. In this paper, we bring together results of our previous studies and add new data and data analyses to develop a consistent 3D structural model for the south-central Taiwan fold-and-thrust belt that can explain key aspects of the seismicity, GPS, and topography data. We interpret the fold-and-thrust belt to be a west-verging, imbricate thrust system developed above a single basal thrust that is breached by ENE-striking faults that are inherited from the continental margin. These breaching faults are associated with ENE-striking transverse zones in the fold-and-thrust belt that are marked by changes in stratigraphy, structural style, strike and dip of the basal thrust, and uplift of the stratigraphic contacts. Along the eastern flank of the fold-and-thrust belt, metamorphic basement rocks are involved in the thrusting. Shortening estimates range from 15 km to >25 km. Much of the seismicity is taking place beneath the basal thrust, in the basement, along the flanks of basement highs and lows where strike-slip and transpressive fault types are common. There are systematic changes in GPS displacement vectors and strain rates across the transverse zones. Topography is higher in areas where basement is involved in the thrusting. The proposed structural model has depth and along-strike consistency, and can explain aspects of the distribution of seismicity, faults types, GPS displacement vectors and strain rates, and topography of the study area, and can therefore be considered a viable model. [ABSTRACT FROM AUTHOR]

Background and Objective: The interleukin-13 (IL-13) -1112 C/T polymorphisms have been analyzed previously in a North European population of patients with aggressive periodontitis. The present study was carried out to investigate the association of polymorphisms in the IL-13 gene with susceptibility to periodontitis in a Taiwanese population., Material and Methods: The genotyping of IL-13 -1112 C/T polymorphisms in 60 patients with aggressive periodontitis, 204 patients with chronic periodontitis and 95 healthy controls was carried out using the polymerase chain reaction-restriction fragment length polymorphism technique. Genotypes and allele frequencies among study groups were compared using Fisher's exact test (p < 0.05). Pearson's chi-square test was used for analysis of the Hardy-Weinberg equilibrium., Results: The distributions of CC genotypes and C alleles between patients with aggressive periodontitis and healthy controls were significantly different (p = 0.034 and 0.046). After adjustment for age, gender, betel nut chewing and smoking status using logistic regression analysis, the odds ratio (OR) was 6.45 [95% confidence interval (CI) = 1.99-23.72, p = 0.003] for aggressive periodontitis. However, the CC genotype was only significantly associated with the risk of aggressive periodontitis in the nonsmoking group (OR = 4.48, 95% CI = 1.31-16.93, p = 0.020)., Conclusion: The CC genotype or C allele appears to increase the risk of developing aggressive periodontitis in Taiwanese subjects., ((c) 2010 John Wiley & Sons A/S.)

Background and Objective: Single nucleotide polymorphisms are assumed to be associated with the differential production of cytokines. We evaluated gene polymorphisms of interleukin-10 (-592C>A, -819C>T and -1082G>A) and interleukin-12B (+16974) in patients with chronic periodontitis (n = 145) and generalized aggressive periodontitis (n = 65) in comparison with healthy controls (n = 126)., Material and Methods: Gene promoter polymorphisms were analyzed by polymerase chain reaction with sequence-specific primers. Genotype and allele frequencies were analyzed using the chi-square test and logistic regression analysis., Results: The interleukin-10 -592 polymorphism showed significant differences among the three groups (p = 0.0330). The genotype frequencies of the -592 locus between the chronic periodontitis and healthy control groups were significantly different (AC vs. AA: odds ratio = 0.33). The combination ATA/ATA seemed to be associated with susceptibility to generalized aggressive periodontitis (p = 0.0276). Patients with the composite ATA/ACC were less likely to develop chronic periodontitis (p = 0.0248). The CC genotype of interleukin-12B (+16974) was related to chronic periodontitis (CC vs. AA, p = 0.0211; CC vs. AA+AC, p = 0.0187). The AC heterozygosity of interleukin-12B was significantly lower in chronic periodontitis vs. healthy controls (p = 0.0500)., Conclusion: The interleukin-10 gene polymorphism at position -592C>A may be associated with a lower risk for development of chronic periodontitis. The interleukin-10 haplotype ATA is associated with generalized aggressive periodontitis. On the other hand, interleukin-12B genetic variants at position +16974 are associated with susceptibility to chronic periodontitis.

Objective: Patients with acute hepatic failure (AHF) were always given first priority on the transplant waiting list. We investigated whether AHF patients will deprive other patients on the waiting list of the chance of liver transplantation (LTx)., Methods and Results: From January 1999 to March 2003, a total of 423 patients were on the transplant waiting list at the National Taiwan University Hospital. Sixty-five of the patients had AHF caused by hepatitis-B-related disease (HBV, n = 52, 80%), Wilson disease (n = 3, 4.6%), drug-induced AHF (n = 3, 4.6%), and other causes (n = 7, 10.8%).Thirty-three patients died and 16 survived by medical treatment. Two received LTx abroad and 14 underwent LTx at our hospital (7 living-related; 7 cadaver). A total of 140 patients died while waiting for a transplant during the period studied. Of them, 107 were among 358 non-AHF patients (30%), and time-to-death interval was 133 +/- 175 days (median: 62); 33 were among 65 AHF patients (51%); time to death was 19 +/- 28 days (median: 8). There were 35 cadaver donor livers available during the period; 28 of 358 non-AHF patients (7.8%), and 7 of 65 AHF patients (10.7%) received cadaveric LTx. Their waiting time totaled 342 +/- 316 and 12 +/- 9 days, respectively (P < .0001)., Conclusion: Most AHF patients died unless they received liver grafts. Even with a higher priority assigned to them, AHF patients still have little chance to get a cadaver donor liver in Taiwan, and non-AHF patients have an even slimmer chance. Therefore, we need to encourage liver donation from living-related donors.