Large scale simulation of watershed mass transport – a case study of Tsengwen reservoir watershed

The Tenth International Symposium on Mitigation of Geo-disasters in Asia Matsue Symposium Place: Shimane Civil Center, Matsue Date: 8 October 2012We present the large scale simulation of watershed mass transport, including landslide, debris-flow and sediment transport. A case study of Tsengwen reservoir watershed under the extreme rainfall triggered by typhoon Morakot is simulated for verification. This approach starts with volume-area relationship formula with inventory method to predict temporal and regional landslide volume production and distribution. Then, debris flow model, Debris-2D, is used to simulate the mass transport of debris-flow from hillslope to fluvial channel. Finally a sediment transport model, NETSTARS, is used for hydraulic and sediment routing in river and reservoir. The integrated simulation for the whole watershed gives a very good agreement with the temporal variation of sediment concentration recorded at the very downstream location

Chronic arsenic exposure and its adverse health effects in Taiwan: A paradigm for management of a global environmental problem

AbstractIt was estimated that, nearly 100 million people are at risk for drinking arsenic (As)-contaminated drinking water. Although the WHO guideline recommends that levels of As in drinking water should not exceed 10 μm/L, it was estimated that more than 30 million people drink As-containing water at levels more than 50 μm/L in Bangladesh and India alone. Therefore, the adverse health effects resulting from chronic As exposure pose a global threat. In Taiwan, studies focusing on the health effects resulting from chronic As exposure through contaminated drinking water have been ongoing for more than 50 years. During the past half century, it was recognized that the impact of high As exposure on human health is much more complicated than originally anticipated. Chronic As exposure resulted in infamous blackfoot disease, which is unique to As endemic areas in Taiwan, and various diseases including cancers and non-cancers. Although the potential-biological outcomes have been well-documented, the pathomechanisms leading from As exposure to occurrence and development of the diseases remain largely unclear. One of the major obstacles that hindered further understanding regarding the adverse health effect resulting from chronic As exposure is documentation of cumulative As exposure from the distant past, which remains difficult as the present technologies mostly document relatively recent As exposure. Furthermore, the susceptibility to As exposure appears to differ between different ethnic groups and individuals and is modified by lifestyle factors including smoking habits and nutrition status. No consensus data has yet been reached even after comparing the study results obtained from different parts of the world focusing on associations between human As toxicity and genetic polymorphisms in terms of cellular detoxification enzymes, tumor suppressor proteins, and DNA repair pathway. With the availability of the new powerful “OMIC” technologies, it may now be possible to gain new path-breaking insights regarding this important environmental health issue. The lessons learned from the past half-century placed Taiwan in an experienced position to actively participate in the international collaborative projects using these novel technologies and standardized methods

Reconstructing Austronesian population history in Island Southeast Asia

Austronesian languages are spread across half the globe, from Easter Island to Madagascar. Evidence from linguistics and archaeology indicates that the ‘Austronesian expansion,’ which began 4,000–5,000 years ago, likely had roots in Taiwan, but the ancestry of present-day Austronesian-speaking populations remains controversial. Here, we analyse genome-wide data from 56 populations using new methods for tracing ancestral gene flow, focusing primarily on Island Southeast Asia. We show that all sampled Austronesian groups harbour ancestry that is more closely related to aboriginal Taiwanese than to any present-day mainland population. Surprisingly, western Island Southeast Asian populations have also inherited ancestry from a source nested within the variation of present-day populations speaking Austro-Asiatic languages, which have historically been nearly exclusive to the mainland. Thus, either there was once a substantial Austro-Asiatic presence in Island Southeast Asia, or Austronesian speakers migrated to and through the mainland, admixing there before continuing to western Indonesia

Prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan

<p>Abstract</p> <p>Background</p> <p>In Taiwan, a distinct ethnic group variation in incidence and mortality rates has been suggested for most carcinomas. Our aim is to identify the role of prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan.</p> <p>Methods</p> <p>Taiwan Cancer Registry records of 9039 subjects diagnosed with oral and pharyngeal carcinoma were analyzed. The population was divided into three ethnic groups by residence, which were Taiwanese aborigines, Hakka and Hokkien communities. Five-year survival rates were estimated by Kaplan-Meier methods. Ethnic curves differed significantly by log-rank test; therefore separate models for Taiwanese aborigines, Hakka and Hokkien were carried out. The Cox multivariate proportional hazards model was used to examine the role of prognostic factors on ethnic survival.</p> <p>Results</p> <p>The five-year survival rates of oral and pharyngeal carcinoma were significantly poorer for Hokkien community (53.9%) and Taiwanese aborigines community (58.1%) compared with Hakka community (60.5%). The adjusted hazard ratio of Taiwanese aborigines versus Hakka was 1.07 (95%CI, 0.86–1.33) for oral and pharyngeal carcinoma mortality, and 1.16 (95%CI, 1.01–1.33) for Hokkien versus Hakka. Males had significantly poor prognosis than females. Subjects with tongue and/or mouth carcinoma presented the worst prognosis, whereas lip carcinoma had the best prognosis. Subjects with verrucous carcinoma had better survival than squamous cell carcinoma. Prognosis was the worst in elderly subjects, and subjects who underwent surgery had the highest survival rate.</p> <p>Conclusion</p> <p>Our study presented that predictive variables in oral and pharyngeal carcinoma survival have been: ethnic groups, period of diagnosis, gender, diagnostic age, anatomic site, morphologic type, and therapy.</p

A panel of tumor markers, calreticulin, annexin A2, and annexin A3 in upper tract urothelial carcinoma identified by proteomic and immunological analysis

BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a tumor with sizable metastases and local recurrence. It has a worse prognosis than bladder cancer. This study was designed to investigate the urinary potential tumor markers of UTUC. METHODS: Between January 2008 and January 2009, urine was sampled from 13 patients with UTUC and 20 healthy adults. The current study identified biomarkers for UTUC using non-fixed volume stepwise weak anion exchange chromatography for fractionation of urine protein prior to two-dimensional gel electrophoresis. RESULTS: Fifty five differential proteins have been determined by comparing with the 2-DE maps of the urine of UTUC patients and those of healthy people. Western blotting analysis and immunohistochemistry of tumor tissues and normal tissues from patients with UTUC were carried out to further verify five possible UTUC biomarkers, including zinc-alpha-2-glycoprotein, calreticulin, annexin A2, annexin A3 and haptoglobin. The data of western blot and immunohistochemical analysis are consistent with the 2-DE data. Combined the experimental data in the urine and in tumor tissues collected from patients with UTUC, the crucial over-expressed proteins are calreticulin, annexin A2, and annexin A3. CONCLUSIONS: Calreticulin, annexin A2, and annexin A3 are very likely a panel of biomarkers with potential value for UTUC diagnosis

Antidepressant-Like Activity of the Ethanolic Extract from Uncaria lanosa Wallich var. appendiculata Ridsd in the Forced Swimming Test and in the Tail Suspension Test in Mice

This study investigated the antidepressant activity of ethanolic extract of U. lanosa Wallich var. appendiculata Ridsd (ULEtOH) for two-weeks administrations by using FST and TST on mice. In order to understand the probable mechanism of antidepressant-like activity of ULEtOH in FST and TST, the researchers measured the levels of monoamines and monoamine oxidase activities in mice brain, and combined the antidepressant drugs (fluoxetine, imipramine, maprotiline, clorgyline, bupropion and ketanserin). Lastly, the researchers analyzed the content of RHY in the ULEtOH. The results showed that ULEtOH exhibited antidepressant-like activity in FST and TST in mice. ULEtOH increased the levels of 5-HT and 5-HIAA in cortex, striatum, hippocampus, and hypothalamus, the levels of NE and MHPG in cortex and hippocampus, the level of NE in striatum, and the level of DOPAC in striatum. Two-week injection of IMI, CLO, FLU and KET enhanced the antidepressant-like activity of ULEtOH. ULEtOH inhibited the activity of MAO-A. The amount of RHY in ULEtOH was 17.12 mg/g extract. Our findings support the view that ULEtOH exerts antidepressant-like activity. The antidepressant-like mechanism of ULEtOH may be related to the increase in monoamines levels in the hippocampus, cortex, striatum, and hypothalamus of mice

Identification of low-abundance proteins via fractionation of the urine proteome with weak anion exchange chromatography

<p>Abstract</p> <p>Background</p> <p>Low-abundance proteins are difficultly observed on the two-dimensional gel electrophoresis (2-DE) maps of urine proteome, because they are usually obscured by high-abundance proteins such as albumin and immunoglobulin. In this study, a novel fractionation method was developed for enriching low-abundance proteins by removing high-abundance proteins and progressive elution with salts of various concentrations.</p> <p>Results</p> <p>Stepwise weak anion exchange (WAX) chromatography, which applied DEAE-Sephacel resin with non-fixed volume elution, was used to fractionate urine proteome prior to performing 2-DE. Urine proteome was separated into four fractions by progressively eluting the column with 0 M, 50 mM, 100 mM, and 1 M NaCl solutions. Most of the heavy and light immunoglobulin chains appeared in the eluent. After the high-abundance proteins were removed, various low-abundance proteins were enriched and could be easily identified. The potential of this method for obtaining diversified fractionations was demonstrated by eluting the column separately with Na₂SO₄and MgCl₂solutions. The 2-DE maps of the fractions eluted with these different salt solutions of identical ionic strength revealed markedly different stain patterns.</p> <p>Conclusion</p> <p>The present study demonstrated that this fractionation method could be applied for purposes of enriching low-abundance proteins and obtaining diversified fractionations of urine, and potentially other proteomes.</p

Predictors of betel quid chewing behavior and cessation patterns in Taiwan aborigines

BACKGROUND: Betel quid, chewed by about 600 million people worldwide, is one of the most widely used addictive substances. Cessation factors in betel quid chewers are unknown. The present study explores prevalence and the quit rate of betel quid chewing in Taiwan aborigines. Our goal was to delineate potential predictors of chewing cessation. METHODS: A stratified random community-based survey was designed for the entire aborigines communities in Taiwan. A total of 7144 participants were included between June 2003 and May 2004 in this study. Information on sociodemographic characteristics, such as gender, age, obesity, education years, marital status, ethnicity, and habits of betel quid chewing, smoking and drinking was collected by trained interviewers. RESULTS: The prevalence of betel quid chewers was 46.1%. Betel quid chewing was closely associated with obesity (OR = 1.61; 95% CI: 1.40–1.85). Betel quid chewers were most likely to use alcohol and cigarettes together. Quit rate of betel quid chewers was 7.6%. Betel quid chewers who did not drink alcohol were more likely to quit (OR = 1.89; 95% CI: 1.43–2.50). Alcohol use is a significant factor related to cessation of betel quid chewing, but smoking is not. CONCLUSION: Taiwan aborigines have a high prevalence of betel quid chewers and a low quit rate. Alcohol use is strongly association with betel quid chewing. Efforts to reduce habitual alcohol consumption might be of benefit in cessation of betel quid chewing

Important prognostic factors for the long-term survival of lung cancer subjects in Taiwan

<p>Abstract</p> <p>Background</p> <p>This study used a large-scale cancer database in determination of prognostic factors for the survival of lung cancer subjects in Taiwan.</p> <p>Methods</p> <p>Total of 24,910 subjects diagnosed with lung cancer was analysed. Survival estimates by Kaplan-Meier methods. Cox proportional-hazards model estimated the death risk (hazard ratio (HR)) for various prognostic factors.</p> <p>Results</p> <p>The prognostic indicators associated with a higher risk of lung cancer deaths are male gender (males versus females; HR = 1.07, 95% confidence intervals (CI): 1.03–1.11), males diagnosed in later periods (shown in 1991–1994 versus 1987–1990; HR = 1.13), older age at diagnosis, large cell carcinoma (LCC)/small cell carcinoma (SCC), and supportive care therapy over chemotherapy. The overall 5-year survival rate for lung cancer death was significantly poorer for males (21.3%) than females (23.6%). Subjects with squamous cell carcinoma (SQCC) and treatment by surgical resection alone had better prognosis. We find surgical resections to markedly increase 5-year survival rate from LCC, decreased risk of death from LCC, and no improved survival from SCC.</p> <p>Conclusion</p> <p>Gender and clinical characteristics (i.e. diagnostic period, diagnostic age, histological type and treatment modality) play important roles in determining lung cancer survival.</p