Study on Cyclic Shear Strength of Soils from Different Methods

This paper compares the cyclic strengths of soils from different methods using intensive investigations at a recent alluvial site on the southwest Taiwan. Generally speaking, the cyclic shear strengths deduced from different methods exhibit the following trend: Block sample \u3e Tube sample ↔ SPT -N (Standard Penetration Test) method \u3e seismic Vs method \u3e CPT-qc (Cone Penetration Test) method

Enhancing the Performance of a Rainfall Measurement System Using Artificial Neural Networks Based Object Tracking Algorithms

With the recent development of optical sensing and digital image processing techniques, high-speed cameras have been applied to measure the microphysical properties of raindrops. However, the performance of such systems are significantly affected by object tracking algorithms. In order to improve the measurement accuracy of rainfall rate and accumulated rainfall, a novel object tracking algorithm based on artificial neural networks (ANN) is proposed in this paper. The ANN model takes the features of each raindrop in the two successive images as inputs including the center coordinates, area, canting angle, the lengths of long axis and minor axis of the equivalent ellipse. The output of the ANN model is the matched probabilities of each pair of raindrops between before and after images. Experimental data were collected during a real rainfall event. Performance comparisons between the traditional and ANN based object tracking algorithms are conducted based on the experimental data. Experimental results suggest the successful matching rate is significantly increased from 87.20% to 95.60% due to the usage of the ANN based algorithm. Hence, the improved disdrometer system is capable of producing more accurate and robust measurements of rainfall status

Genetic population structure of the alpine species Rhododendron pseudochrysanthum sensu lato (Ericaceae) inferred from chloroplast and nuclear DNA

<p>Abstract</p> <p>Background</p> <p>A complex of incipient species with different degrees of morphological or ecological differentiation provides an ideal model for studying species divergence. We examined the phylogeography and the evolutionary history of the <it>Rhododendron pseudochrysanthum </it>s. l.</p> <p>Results</p> <p>Systematic inconsistency was detected between gene genealogies of the cpDNA and nrDNA. Rooted at <it>R. hyperythrum </it>and <it>R. formosana</it>, both trees lacked reciprocal monophyly for all members of the complex. For <it>R. pseudochrysanthum </it>s.l., the spatial distribution of the cpDNA had a noteworthy pattern showing high genetic differentiation (F_ST= 0.56-0.72) between populations in the Yushan Mountain Range and populations of the other mountain ranges.</p> <p>Conclusion</p> <p>Both incomplete lineage sorting and interspecific hybridization/introgression may have contributed to the lack of monophyly among <it>R. hyperythrum</it>, <it>R. formosana </it>and <it>R. pseudochrysanthum </it>s.l. Independent colonizations, plus low capabilities of seed dispersal in current environments, may have resulted in the genetic differentiation between populations of different mountain ranges. At the population level, the populations of Central, and Sheishan Mountains may have undergone postglacial demographic expansion, while populations of the Yushan Mountain Range are likely to have remained stable ever since the colonization. In contrast, the single population of the Alishan Mountain Range with a fixed cpDNA haplotype may have experienced bottleneck/founder's events.</p

Hypokalemia, Its Contributing Factors and Renal Outcomes in Patients with Chronic Kidney Disease

Background: In the chronic kidney disease (CKD) population, the impact of serum potassium (sK) on renal outcomes has been controversial. Moreover, the reasons for the potential prognostic value of hypokalemia have not been elucidated. Design, Participants & Measurements 2500 participants with CKD stage 1–4 in the Integrated CKD care program Kaohsiung for delaying Dialysis (ICKD) prospective observational study were analyzed and followed up for 2.7 years. Generalized additive model was fitted to determine the cutpoints and the U-shape association between sK and end-stage renal disease (ESRD). sK was classified into five groups with the cutpoints of 3.5, 4, 4.5 and 5 mEq/L. Cox proportional hazard regression models predicting the outcomes were used. Results: The mean age was 62.4 years, mean sK level was 4.2±0.5 mEq/L and average eGFR was 40.6 ml/min per 1.73 m2. Female vs male, diuretic use vs. non-use, hypertension, higher eGFR, bicarbonate, CRP and hemoglobin levels significantly correlated with hypokalemia. In patients with lower sK, nephrotic range proteinuria, and hypoalbuminemia were more prevalent but the use of RAS (renin-angiotensin system) inhibitors was less frequent. Hypokalemia was significantly associated with ESRD with hazard ratios (HRs) of 1.82 (95% CI, 1.03–3.22) in sK 5 mEq/L conferred 1.6-fold (95% CI,1.09–2.34) increased risk of ESRD compared with sK = 4.5–5 mEq/L. Hypokalemia was also associated with rapid decline of renal function defined as eGFR slope below 20% of the distribution range. Conclusion: In conclusion, both hypokalemia and hyperkalemia are associated with increased risk of ESRD in CKD population. Hypokalemia is related to increased use of diuretics, decreased use of RAS blockade and malnutrition, all of which may impose additive deleterious effects on renal outcomes

Conservation genetics and phylogeography of endangered and endemic shrub Tetraena mongolica (Zygophyllaceae) in Inner Mongolia, China

<p>Abstract</p> <p>Background</p> <p><it>Tetraena mongolica </it>(Zygophyllaceae), an endangered endemic species in western Inner Mongolia, China. For endemic species with a limited geographical range and declining populations, historical patterns of demography and hierarchical genetic structure are important for determining population structure, and also provide information for developing effective and sustainable management plans. In this study, we assess genetic variation, population structure, and phylogeography of <it>T. mongolica </it>from eight populations. Furthermore, we evaluate the conservation and management units to provide the information for conservation.</p> <p>Results</p> <p>Sequence variation and spatial apportionment of the <it>atp</it>B-<it>rbc</it>L noncoding spacer region of the chloroplast DNA were used to reconstruct the phylogeography of <it>T. mongolica</it>. A total of 880 bp was sequenced from eight extant populations throughout the whole range of its distribution. At the cpDNA locus, high levels of genetic differentiation among populations and low levels of genetic variation within populations were detected, indicating that most seed dispersal was restricted within populations.</p> <p>Conclusions</p> <p>Demographic fluctuations, which led to random losses of genetic polymorphisms from populations, due to frequent flooding of the Yellow River and human disturbance were indicated by the analysis of BEAST skyline plot. Nested clade analysis revealed that restricted gene flow with isolation by distance plus occasional long distance dispersal is the main evolutionary factor affecting the phylogeography and population structure of <it>T</it>. <it>mongolica</it>. For setting a conservation management plan, each population of <it>T</it>. <it>mongolica </it>should be recognized as a conservation unit.</p

YamSat: the First Picosatellite being Developed in Taiwan

This paper describes the current planning and design of the YamSat, the first picosatellite being developed in Taiwan. The design, analysis, manufacture, integration, test and operation of the YamSat will be performed by the National Space Program Office (NSPO), Taiwan, R.O.C, in cooperation with other domestic organizations and companies. It is a member of the CubeSat [1], 10cm x 10cm x 10cm size and within 1kg mass. The major objective of the YamSat is to qualify in space the components and technology developed in Taiwan, including a micro-spectrometer payload using Micro Electro Mechanical Systems (MEMS) technology. The YamSat will be ready for flight in the middle of 2002

Variability in Estimated Glomerular Filtration Rate by Area under the Curve Predicts Renal Outcomes in Chronic Kidney Disease

Greater variability in renal function is associated with mortality in patients with chronic kidney disease (CKD). However, few studies have demonstrated the predictive value of renal function variability in relation to renal outcomes. This study investigates the predictive ability of different methods of determining estimated glomerular filtration rate (eGFR) variability for progression to renal replacement therapy (RRT) in CKD patients. This was a prospective observational study, which enrolled 1,862 CKD patients. The renal end point was defined as commencement of RRT. The variability in eGFR was measured by the area under the eGFR curve (AUC)%. A significant improvement in model prediction was based on the −2 log likelihood ratio statistic. During a median 28.7-month follow-up, there were 564 (30.3%) patients receiving RRT. In an adjusted Cox model, a smaller initial eGFR AUC%_12M (P<0.001), a smaller peak eGFR AUC%_12M (P<0.001), and a larger negative eGFR slope_12M (P<0.001) were associated with a higher risk of renal end point. Two calculated formulas: initial eGFR AUC%_12M and eGFR slope_12M were the best predictors. Our results demonstrate that the greater eGFR variability by AUC% is associated with the higher risk of progression to RRT

Variability in Estimated Glomerular Filtration Rate by Area under the Curve Predicts Renal Outcomes in Chronic Kidney Disease

Greater variability in renal function is associated with mortality in patients with chronic kidney disease (CKD). However, few studies have demonstrated the predictive value of renal function variability in relation to renal outcomes. This study investigates the predictive ability of different methods of determining estimated glomerular filtration rate (eGFR) variability for progression to renal replacement therapy (RRT) in CKD patients. This was a prospective observational study, which enrolled 1,862 CKD patients. The renal end point was defined as commencement of RRT. The variability in eGFR was measured by the area under the eGFR curve (AUC)%. A significant improvement in model prediction was based on the −2 log likelihood ratio statistic. During a median 28.7-month follow-up, there were 564 (30.3%) patients receiving RRT. In an adjusted Cox model, a smaller initial eGFR AUC% 12M ( &lt; 0.001), a smaller peak eGFR AUC% 12M ( &lt; 0.001), and a larger negative eGFR slope 12M ( &lt; 0.001) were associated with a higher risk of renal end point. Two calculated formulas: initial eGFR AUC% 12M and eGFR slope 12M were the best predictors. Our results demonstrate that the greater eGFR variability by AUC% is associated with the higher risk of progression to RRT

Prognostic Cardiovascular Markers in Chronic Kidney Disease

Chronic kidney disease (CKD), including end-stage renal disease (ESRD), is a public health issue worldwide, and is associated with high rates of morbidity and mortality. In addition, cardiovascular disease is a major cause of mortality in these patients. Both traditional and nontraditional risk factors associated with CKD can lead to remodeling of the myocardium and blood vessels, thereby resulting in cardiomyopathy, atherosclerosis and arterial stiffness. This can subsequently lead to ischemic heart disease, heart failure, cardiovascular death, rapid renal progression and progression to ESRD. Identifying these risk factors to allow for aggressive preventive and interventional strategies is important for the management of patients with CKD. This aim of this review was to survey the clinical outcomes of CKD using cardiac and vascular markers including echocardiographic parameters, systolic time intervals, electrocardiography, heart rate variability, ankle-brachial index, pulse wave velocity, differences between interarm and interankle blood pressure, and vascular calcification

Lessons Learned of NSPO’s Picosatellite Mission: Yamsat - 1A, 1B & 1C

The YamSat is the first developed picosatellite in National Space Program Office’s (NSPO), Taiwan, R.O.C. It is scheduled to flight in the CubeSat launch in 2003. The rapid-prototyping system engineering different from the past formal discipline opens a new satellite development model in NSPO. The YamSat Test Readiness Review Meeting was successfully held in January 2002 and the environmental tests were completed by end March 2002. Besides the breadboard model and engineering test bed to prove of operation concept are built, three YamSats (1A, 1B, & 1C) instead of one are manufactured with slightly different configurations and purposes. The YamSat- 1A is for flight with ambitious and novel R.O.C. made components, including 15 domestic organizations and companies’ participation. The YamSat-1B is basically for backup purpose and demonstration, whereas the YamSat-1C is for amateur communication experiment end-to-end field test, and for public education purpose. This new experience gives fruitful lessons learned and provides low cost space experimentation and education to the next built picosatellites in Taiwan’s universities. Detailed mission and lessons learned are addressed in this paper