Top PDF Coprostanol in a sediment core from the anoxic Tan-Shui estuary, Taiwan.

Coprostanol in a sediment core from the anoxic Tan-Shui estuary, Taiwan.

Coprostanol in a sediment core from the anoxic Tan-Shui estuary, Taiwan.

A short sediment core with a length of approximately 40 cm taken from the anoxic Tan-Shui estuary, Taiwan, was analysed for extractable and bound coprostanol (5β-cholestan-3β-ol), chol[r]

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Coprostanol in a Sediment Core from the Anoxic Tan-Shui Estuary, Taiwan

Coprostanol in a Sediment Core from the Anoxic Tan-Shui Estuary, Taiwan

Received 22 December 1993 and in revised form 7 July 1994 Key words: coprostanol; extractable; bound; sediment; diagenesis A short sediment core with a length of approximately 40 cm taken from the anoxic Tan-Shui estuary, Taiwan, was analysed for extractable and bound coprostanol (5â-cholestan-3â-ol), cholestanol (5á-cholestan-3â-ol) and choles- terol (cholest-5-en-3â-ol). Extractable Ócoprostanol and cholestanol concen- trations exhibit an abrupt change at a depth of about 20 cm, which supposedly marks the time when a sewage treatment plant became operational in the estuary in 1980. The Ócoprostanol/cholesterol and cholestanol/cholesterol ratios are comparatively higher in sediment than in the sewage e ffluent, implying some degree of diagenesis in the extractable phase. Anoxicity must have played a crucial role in the preservation and diagenesis of the sterols. In the upper layer (c. top 20 cm), the concentrations of extractable Ócoprostanol, normalized to total organic carbon (TOC), increase down the core. Extractable cholestanol exhibits the same trend, but extractable cholesterol shows the opposite trend. This indicates cholesterol reduction to these two stanols. In addition, both bound Ócoprostanol/TOC and cholestanol/TOC display a decreasing trend with core depth and no pronounced concentration change at 20 cm depth. The averages of percent bound sterols are in the following order:
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Coprostanol distribution in marine sediments off southwestern Taiwan.

Coprostanol distribution in marine sediments off southwestern Taiwan.

Abstract One of the major industries in southern Taiwan is pigfarming along the Kaoping River; some two million animals are being raised along the river banks. Excretions from pigs, treated and untreated, are discharged directly into the river and eventually carried to the sea. Twenty-four surface sediments and one sediment core off southwestern Taiwan were analyzed to determine quantitatively the extent of coprostanol addition and its distribution and to obtain the input of coprostanol over the past. Geographically, the percent coprostanol is highest around the river mouth, and decreases to about 1% at the shelf break and about 0% at a distance of approximately 40 nautical miles (74 km) from the river mouth. The progressive seaward decline of percent coprostanol from the river mouth can be attributed to [1]
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Sedimentary Coprostanol in Kaohsiung Harbour and the Tan-Shui Estuary, Taiwan

Sedimentary Coprostanol in Kaohsiung Harbour and the Tan-Shui Estuary, Taiwan

Jeng & Han (1991) made a preliminary survey of sedimentary coprostanol concentrations along the western Taiwan coast, found Kaohsiung Harbour (six data) and th[r]

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Alkanol and sterol degradation in a sediment core from the continental slope off southwestern Taiwan

Alkanol and sterol degradation in a sediment core from the continental slope off southwestern Taiwan

All rights reserved. Institute of Oceanography, National Taiwan University, Taipei, Talwan, Republic of China 2. 36 cm in length and sectioned at 4 cm intervals) collected [r]

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Core technologies and key industries in Taiwan from 1978 to 2002: A prespective from patent analysis

Core technologies and key industries in Taiwan from 1978 to 2002: A prespective from patent analysis

a Department of Mechanical Engineering, National Taiwan University Taipei (Taiwan) b Department of Library and Information Science, National Taiwan University, Taipei (Taiwan) c Department of International Business, Yu Da University, Miaoli (Taiwan) This paper uses United States patent classification analysis to study the development of core technologies and key industries in Taiwan over the last 25 years, from 1978 to 2002. After counting the number of Taiwan-held United States granted utility patents, the authors divide the years into three phases: from 1978 to 1994, with less than 500 patents each year; from 1995 to 1999, with 500–2,500 patents each year; from 2000 to 2002, with annual patents greater than 2,500. The results show that for both Taiwan’s core technologies and key industries, there was a great diversity at the first phase, while a mainstream forms and matures at the second and the third phases. However, industrial development at the third phase was more concentrated and focused than previous ones. Overall, Taiwan has clearly moved from a manufacturing-based economy to an innovation-based one, with its focus on high-tech industries during the previous 25 years.
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Coprostanol distribution in marine sediments off southwestern Taiwan

Coprostanol distribution in marine sediments off southwestern Taiwan

the river mouth can be attributed to [I] dilution of coprostanol by uncontaminated sediment and/or sediment containing relatively lower levels of coprostanol, [2/ [r]

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A quick method to identify engraulid fish larvae in the Tanshui River estuary of northern Taiwan.

A quick method to identify engraulid fish larvae in the Tanshui River estuary of northern Taiwan.

Abstract Five species of larval engraulids, Engraulis japonica Schlegel, Encrasicholina punctifer Fowler, E. heteroloba (Ruppell), Stolephorus insularis Hardenberg, and Thryssa dussumieri (Valenciennes), were found in coastal waters off the Tanshui River Estuary, northern Taiwan during the period from May 1992 through November 1993. Their sizes ranged between 8 and 46 mm SL. Comparing the meristics, morphometrics, and pigmentations of the 5 species, we found pigment patterns on the ventral side of the larvae that can be used as a key character to discriminate these species.
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The Influence of River Discharge on Salinity Intrusion in the Tanshui Estuary, Taiwan

The Influence of River Discharge on Salinity Intrusion in the Tanshui Estuary, Taiwan

In this study, it is the flushing time of the entire tidal portion of the Tanshui River system we were in- vestigating, not just the portion of the river conforming to the [r]

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Seasonal variation and flux of dissolved nutrients in the Danshuei Estuary, Taiwan: A hypoxic subtropical mountain river

Seasonal variation and flux of dissolved nutrients in the Danshuei Estuary, Taiwan: A hypoxic subtropical mountain river

"Institute of Chemistry, Academia Sinica, Taipei, Taiwan Abstract The metal string complexes with di!erent metal ions and various lengths have been successfully synthesized and structurally characterized. The crystal and molecular structure of nonanickel complex [Ni9(l9-(peptea)4Cl2] which is the longest metal string at this moment will be reported. Crystal data for [Ni9(l9-(peptea)4Cl2](C2H4Cl2)10: Space group, monoclinic C 2/c, a"27.0453(6), b"42.6678(5), c"37.4268(6) A s , b"109.539(1)3, <"40702(1) As3, Z"12, RF"12% for the observed re#ections (I'2p(I)). The band structure calculation of in"nite one-dimensional metal chains of Ni II and CrII based on the structure of nonanickel complex will be presented. Finally, the metal string complexes [M IInL4X2] will be chemisorbed on the Ag or Au surface and the potential application of these complexes as a molecular metal wire will be demonstrated. ( 2000 Elsevier Science B.V. All rights reserved.
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Simulation of water quality and plankton dynamics in the Danshuei River estuary, Taiwan

Simulation of water quality and plankton dynamics in the Danshuei River estuary, Taiwan

Because of the relatively large tidal range compared to the depth of the system, the residence time of the main stem estuary was found to be 2.2 days or less. [9] The estuarine portion of the river system runs through the capital City of Taipei, with a population of 6 million in its metropolitan area. Huge amounts of domestic wastewater, mostly untreated raw sewage, are discharged into the estu- ary daily. The water quality has been severely degraded for decades. Hypoxic/anoxic conditions commonly occur in the upper and middle reaches of the estuary during summer months. [10] Viable biological activities are observed only in the lowest reach of the estuary where the pollutant concen- trations are reduced as a result of dilution by seawater. [15] A three-year observational study of the system from 1998 to 2001 conducted by Taiwan’s Academia Sinica reported that the chlorophyll a concentration hardly exceeded 5 mg/m 3 . The primary production rate was on the order of 0.2 g C/m 3 /day. Zooplankton biomass was observed to range from 1 to 14 mg C/m 3 . If the amount of carbon fixed by the phytoplankton species is not transferred to the higher trophic level it is termed as nuisance species. Zooplankton play a pivotal role in the transfer of carbon from primary producer, such as phytoplankton, to higher consumers, such as fishes. However few studies have been conducted
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Observed sediment fluxes in the southwesternmost Okinawa Trough enhanced by episodic events: flood runoff from Taiwan rivers and large earthquakes

Observed sediment fluxes in the southwesternmost Okinawa Trough enhanced by episodic events: flood runoff from Taiwan rivers and large earthquakes

c Institute of Marine Geology and Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC Received 18 December 2002; received in revised form 10 October 2003; accepted 20 January 2004 Abstract The sediment fluxes to the southwesternmost Okinawa Trough (SOT) off northeast Taiwan have been measured with four sets of sediment traps. The sediment fluxes observed were much higher than those in many marginal seas and showed great variations in time and space. The fluxes exhibited a drastic seaward decline from northeastern Taiwan to the central trough and an increase with depth. Temporal variability of fluxes was in a wide range from three times to one order of magnitude for certain traps. The observed sediment fluxes had a positive correlation with river runoff from the Lanyang Hsi, a river in northeastern Taiwan. Usually, the highest fluxes could be attributed to episodic events, for example, typhoon passages, which always cause ample rainfall leading to high runoff and sediment discharge, and sediment fluxes that were observed during typhoon passages accounted for more than 50% of the long-term flux. Large earthquakes are suggested to be responsible for some sediment flux anomalies observed on the nearby steep slope because of a good match in time between sediment collection and earthquake occurrence. A conceptual model is proposed to illustrate the sources and transport of the SOT sediment. The study highlights the greater contribution of Taiwan fluvial sediments to the SOT compared to that of the Changjiang, and it provides evidence demonstrating the combined effects of river runoff and large earthquakes on the sediment fluxes observed in such a deep marginal sea.
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Abrasion resistance design of sediment sluicing tunnel in Taiwan a case study

Abrasion resistance design of sediment sluicing tunnel in Taiwan a case study

The in-situ inspection results show that the invert abrasion resistance layer of the ZRSST was damaged at the changing place of slope and flow velocity due to the impact of high mud-containing and concrete-containing water. Only partial abrasion was observed for the invert abrasion resistance layer. However, there was no significant difference in the abrasion resistance layer of the invert after four sediment sluicing operations. The water leakage and spalling phenomenon of the abrasion resistance layer on the sidewall is mainly caused by the heavy rain, leading to increased groundwater level and the increased moisture at the interface between the concrete lining and the abrasion resistance layer, which reduced the bonding strength.
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Residence time of the Danshuei River estuary, Taiwan

Residence time of the Danshuei River estuary, Taiwan

Abstract The residence time of an estuary is defined in this study as the average time the initially existing water parcels reside in the system before they are flushed out. The residence time of the Danshuei River is calculated through a series of numerical experiments using a laterally integrated two-dimensional hydrodynamic eutrophication model (HEM-2D). The results show that the residence time is on the order of 1e2 days under the mean river flow to zero river flow condition, which is very short compared with most time scales of biogeochemical processes. A procedure is developed to quantify individual contribution to flushing by each of the three major physical transport mechanisms: tide, river discharge, and the density induced circulation. The results indicated that, in general conditions, tidal flushing exerts the greatest influence to the flushing of the Danshuei River estuary, while the density induced circulation hardly contributes any. Tidal transport contributes more than 50% of the flushing when river discharge is below its long- term mean. The suitability of applying the tidal prism method, the modified tidal prism methods, and the fraction of freshwater method in this estuary is also investigated. The relatively short residence time is likely to be one of the limiting factors that result in low phytoplankton biomass in spite of extremely high nutrient concentrations, and causes a significant fraction of pollutants to exert their effects in the coastal waters outside the estuary.
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Aliphatic hydrocarbon concentrations in short sediment cores from the southern Okinawa Trough: Implications for lipid deposition in a complex environment

Aliphatic hydrocarbon concentrations in short sediment cores from the southern Okinawa Trough: Implications for lipid deposition in a complex environment

Marine sediments may preserve a record of past or on-going environmental processes and compo- nents, both natural and human induced. Records in marine sediment can provide information about past biological, chemical and physical oceano- graphic conditions. As to chemistry, important parameters may include mineral content, major elements, trace elements, total organic carbon (TOC), stable isotope geochemistry, specific organic pollutants, biochemical markers, etc. Organic geo- chemical data can be used to estimate the total mass of certain compounds in the bottom sediment, to interpret downcore environmental changes as in- dicated by the abundance and distribution of some compounds present in cores, etc. Because of their stability in the natural environment, aliphatic hydrocarbons are selected and used as a measure for indicating possible change of lipids in sediment cores, which would reflect changes in lipid concen- tration during sedimentation. The objective of this study was to use the variations of parameters derived from aliphatic hydrocarbon concentrations in 7 short sediment cores collected from the SOT for inferring the condition of lipid deposition in this area.
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Geochemical and carbon isotopic characterization of particles collected in sediment traps from the East China Sea continental slope and the Okinawa Trough northeast of Taiwan

Geochemical and carbon isotopic characterization of particles collected in sediment traps from the East China Sea continental slope and the Okinawa Trough northeast of Taiwan

Tang et al., 1997). More specifically, as the Kuroshio current flow over the Okinawa Trough and turns eastwards to continue its journey to the North Pacific, the shelf-side of the Kuroshio water branches off from its mainstream and intrudes northwestwards through the NMHC onto the East China Sea continental slope. It then turns counter-clockwise and reverses its direction, flowing southeastwards through the MHC, then regions its mainstream and continues to the North Pacific. The circula- tion pattern, however, may vary seasonally and spatially because of the variability of the winter Monsoon and botton topography, and provides the driving force for transporting sediment particles in the region as seen in our ASMF measurements from the traps. In addition, the central region of this counter flow system is located at the exact place where persistent upwelling of the cold and nutrient-rich subsurface waters is found, yet varies throughout the years. The increased supply of nutrients by these upwelled waters would therefore support a high biological activity in place.
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Quality of care for lung cancer in Taiwan: A pattern of care based on core measures in the Taiwan Cancer Database Registry

Quality of care for lung cancer in Taiwan: A pattern of care based on core measures in the Taiwan Cancer Database Registry

We found that POC in Taiwan was consistent with new clinical evidence in a previous study based on registry data from a single institution. 18 We also found increasing compliance with some core measures with increasing years with the TCDB project. A previous systematic review has revealed that outcome is improved with the adop- tion of clinical practice guidelines. 19 As these core measures were established from evidence- based clinical guidelines, 15 we believe that QOC for lung cancer in Taiwan will be improved in the near future.
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Relationship between growth-rate and age at recruitment of Anguilla-japonica elvers in a Taiwan estuary as inferred from otolith growth increments.

Relationship between growth-rate and age at recruitment of Anguilla-japonica elvers in a Taiwan estuary as inferred from otolith growth increments.

Therefore, the initial growth increment in otoliths of elvers was proposed to be deposited during the transitional stage when larvae switch from endogenous yolk-sac nutrition to exo[r]

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Estimating the Effects of Sediment from a Bypass Tunnel on the Management of Attached Algal Biomass

Estimating the Effects of Sediment from a Bypass Tunnel on the Management of Attached Algal Biomass

Abstract Supplying sediments to sediment deficient areas in downstream reaches of a dam can promote the detachment of overgrown algae. Therefore, permanent sediment supply should be secured to maintain the algal growth under control, e.g., using sediment bypass tunnel, because the attached algae can overgrow again within several months. However, long term effects of sediment supply via bypass tunnels on algal biomass have not been previously assessed. In this study, yearly algal biomass in downstream reaches of a dam equipped with a sediment bypass tunnel was measured to estimate the yearly reduction in the amount of algal biomass. In order to achieve this goal, a model for predicting algal biomass was developed. The model used involved multiple variables because attached algae are easily affected by several factors. The accuracy of the model in predicting algal biomass was proven; then, the changes in algal biomass in the presence and absence of sediments from the bypass tunnel were simulated. In the simulation, each scenario was evaluated using three different values of D 60 , the index of the average diameter on riverbeds. The six simulations indicated that the model can quantify two types of effects of the sediment: the direct attack on algae during flood, which is effective in reducing overgrown algae, and the reduction in grain size of the riverbed material, which prevents algae from overgrowing.
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Tropical cyclone triggering of sediment discharge in Taiwan

Tropical cyclone triggering of sediment discharge in Taiwan

This spatial distribution is not random, and is thus unlikely to average out in a simple sense on geological timescales. On the timescale of individual storms, the precipitation distribu- tion and associated surficial processes depend on the physics of tropical cyclone-topography interactions as illustrated in this study; on longer timescales (decadal and beyond) they depend on the climatology of tropical cyclone tracks. Shifts in the relative probability of tropical cyclone tracks or intensity could potentially effect changes in erosion by altering the spatial distribution of heavy tropical cyclone rainfall. Changes in western Pacific tropical cyclone tracks and intensity on Holocene or longer timescales are almost entirely unknown at present, but depend on changes in sea surface temperatures as well as large-scale atmospheric processes. The proper treatment of tropical cyclones in landscape evolution models requires a better understanding of the long-term localization of precipitation and surface processes in tropical mountain belts; the present results thus point to some inadequacies in current modeling approaches.
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