680 research outputs found

    Effect of steam jet cooking on the destruction of corn starches

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    AbstractSteam jet cooking has been used for years to prepare aqueous starch dispersions for food application. The steam jet cooking generates high shear stress to starch. The objective of this research is to study the effect of shear stress on structure of corn starch granules by steam jet cooking. A laboratory scale steam jet cooker has been established with flow rate about 1L/min. Three kinds of corn starch, waxy, regular, and high amylose were used. Starch slurries (5% w/w) were cooked by steam jet cooker at temperature 100°C (SJ100), 120°C (SJ120) and 135°C (SJ135) compared with hot water boiling at 90°C 30min (HB). The insoluble particles of cooked starches were investigated by particle size analyzer, scanning electron microscope (SEM) and damage starch assay kit. There was a significant decrease in percent yield of insoluble particles of cooked dispersions for all starches in the order HB > SJ100 > SJ120 > SJ 135.The data also showed that SJ100 has higher destruction than HB, although the temperature of heat treatment was similar. The particle size of cooked starches was much larger than uncooked starches, and the particle size of HB was larger than SJ100 for all starches. This may be due to the time of cooking, 30min for HB vs. a few sec for SJ100. Percentage damaged starch of cooked dispersions for all starches became higher with increasing of cooking temperature. Although, the time of heat treatment was much shorter for SJ100 than HB, the damaged starch was higher as well. Those date all revealed the effect of shear stress from steam cooking. On SEM observation, the damaged granules showed sponge like structure for the starch dispersions cooked by HB. The starches heated by steam jet cooking were fractured into small fragments

    Interannual Variation of Springtime Biomass Burning in Indochina: Regional Differences, Associated atmospheric dynamical changes, and downwind impacts

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    During March and April, widespread burning occurs across farmlands in Indochina in preparation for planting at the monsoon onset. The resultant aerosols impact the air quality downwind. In this study, we investigate the climatic aspect of the interannual variation of springtime biomass burning in Indochina and its correlation with air quality at Mt. Lulin in Taiwan using long-term (2005–2015) satellite and global reanalysis data. Based on empirical orthogonal function (EOF) analysis, we find that the biomass burning activities vary with two geographical regions: northern Indochina (the primary EOF mode) and southern Indochina (the secondary EOF mode). We determine that the variation of biomass burning over northern Indochina is significantly related with the change in aerosol concentrations at Mt. Lulin. This occurs following the change in the so-called India-Burma Trough in the lower and middle troposphere. When the India-Burma Trough is intensified, a stronger northwesterly wind (to the west of the trough) transports the dryer air from higher latitude into northern Indochina, and this promotes local biomass burning activities. The increase in upward motion to the east of the intensified India-Burma Trough lifts the aerosols, which are transported toward Taiwan by the increased low-level westerly jet. Further diagnoses revealed the connection between the India-Burma Trough and the South Asian jet\u27s wave train pattern as well as the previous winter\u27s El Niño–Southern Oscillation phase. This information highlights the role of the India-Burma Trough in modulating northern Indochina biomass burning and possibly predicting aerosol transport to East Asia on the interannual time scale

    Persistent and multisite homophobic harassment during childhood and adolescence and its association with school difficulties in gay and bisexual men in Taiwan

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    Background: Homophobic harassment can compromise mental health of sexual minority youths. Objectives: This study examined the rates of persistent and multisite homophobic harassment and their associations with school difficulties during childhood and adolescence among gay and bisexual men in Taiwan. Methods: Participants were recruited through advertisements on the Facebook, Bulletin Board Systems, and the home pages of health promotion and counseling centers for the gay, lesbian, and bisexual community. The experiences of traditional and cyber harassment based on gender role nonconformity and sexual orientation of 500 gay or bisexual men were examined. The associations of multisite and persistent harassment victimization with school difficulties were evaluated. Results: A total of 239 (47.8%) and 131 (26.2%) participants experienced persistent and multisite harassment victimization, respectively. Harassment victimization was significantly associated with low satisfaction with academic performance in any stage of study. Moreover, the participants who were harassed in senior high schools were more likely to miss classes or be truant than those who were not harassed. The victims of multisite harassment at senior high schools were more likely to miss classes or be truant than those of school-only harassment. Discussion: Prevention and intervention programs are warranted to reduce homophobic harassment in sexual minority youths

    Taiwanese Version of the EQ-5D: Validation in a Representative Sample of the Taiwanese Population

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    Background/PurposeWe know of no validated Taiwanese-language instrument to measure a utility of the patient's health. Our aim was to evaluate the reliability and validity of a Taiwanese version of the EuroQol instrument (EQ-5D) in a Taiwanese population.MethodsQuestionnaires containing the Taiwanese versions of the EQ-5D and the Short-Form 12 Health Survey (SF-12) were sent to 12,923 people in Taiwan in December 2002. Concurrent validity of the EQ-5D was analyzed by assuming that subjects with problems in any EQ-5D dimensions had decreased SF-12 scores. Discriminant validity of the EQ-5D was analyzed by assuming that subjects with the following characteristics had lowered EQ-5D indexes and scores on the EQ-5D visual analog scale (VAS): more chronic diseases than others, serious illness, more hospitalizations in the past year than others, poor general health, and more outpatient visits than others. Test—retest reliability was analyzed in a subgroup of respondents who were evaluated twice within a month by using the intraclass correlation coefficient and the k method.ResultsThe general survey response rate was 12.7% (1644 of 12,923). SF-12 scores were lower in subjects reporting problems on EQ-5D dimensions than in others without such problems (p < 0.01). Subjects with more health problems than others had lower EQ-5D indexes and VAS scores (p < 0.01). The physical dimension of the EQ-5D was more strongly correlated with the SF-12 Physical Component Summary than with the Mental Component Summary; this finding satisfied the a priori hypothesis. For test—retest reliability of items on the EQ-5D, k values ranged from 0.49 to 1 (p < 0.001).ConclusionThe Taiwanese EQ-5D instrument appears to be a moderately valid and reliable tool for measuring the health status of the general population in Taiwan

    Cost-effectiveness of Different Advanced Life Support Providers for Victims of Out-of-hospital Cardiac Arrests

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    Background/purposeThe survival rate of out-of-hospital cardiac arrest (OHCA) is only about 1.4% in Taiwan. The best configuration to achieve optimal outcomes in OHCA is still uncertain for many communities. The purpose of this study was to investigate the cost-effectiveness of two models of providing advanced life support (ALS) services, emergency medical technicians (EMTs) vs. emergency physicians (EPs), in a two-tiered emergency medical services (EMS) system.MethodsThis was a prospective, observational, multicenter study comparing ALS provided by EMTs vs. EPs for the management of victims of OHCA. The study population consisted of patients experiencing OHCA of non-traumatic origin in Taipei city, Taiwan, between November 1999 and December 2000, for whom ALS was activated. We performed a cost-effectiveness analysis to determine the economic attractiveness of these two ALS provider programs. The outcome measurements were aggregate costs, survival and incremental cost per life saved. Sensitivity analyses were performed on all variables.ResultsThe expected total cost per OHCA patient was US2248.19andUS2248.19 and US832.07 for the EMT and EP programs, respectively. The overall survival rate was 4.4%. The survival rate was 9.3% for the EMT program and 2.6% for the EP program. The incremental cost-effectiveness ratio (ICER) of EMTs vs. EPs was US$21,136 per life saved. The ICER was sensitive to hospital admission cost changes and the probability of survival to discharge in patients admitted to hospital in the EMT program. The increased survival rate of OHCA patients in the EMT program may be attributable to the services of the hospital and/or the EMT program.ConclusionThe use of EMTs as ALS care providers for OHCA patients in the two-tiered EMS system resulted in a reasonable cost-effectiveness ratio. EMTs could be considered as the second tier of EMS systems in urban areas in Taiwan

    Trichome Lengths of the Heterocystous N\u3csub\u3e2\u3c/sub\u3e-Fixing Cyanobacteria in the Tropical Marginal Seas of the Western North Pacific

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    Calothrix rhizosoleniae and Richelia intracellularis are heterocystous cyanobacteria found in the tropical oceans. C. rhizosoleniae commonly live epiphytically on diatom genera Chaetoceros (C-C) and Bacteriastrum (B-C) while R. intracellularis live endosymbiotically within Rhizosolenia (R-R), Guinardia (G-R), and Hemiaulus (H-R); although, they occasionally live freely (FL-C and FL-R). Both species have much shorter trichomes than the other marine filamentous cyanobacteria such as Trichodesmium spp. and Anabaena gerdii. We investigated the trichome lengths of C. rhizosoleniae and R. intracellularis in the South China Sea (SCS) and the Philippine Sea (PS) between 2006 and 2014. On average, H-R had the shortest trichome lengths (3.5 cells/trichome), followed by B-C and C-C (4.9–5.2 cells/trichome) and FL-C (5.9 cells/trichome), and R-R, G-R, and FL-R had the longest trichome lengths (7.4–8.3 cells/trichome). Field results showed the trichome lengths of C-C and B-C did not vary seasonally or regionally. However, FL-C and H-R from the SCS and during the cool season had longer trichomes, where/when the ambient nutrient concentrations were higher. R-R, G-R, and FL-R also showed regional and seasonal variations in trichome length. Ultrastructural analysis found no gas vesicles within the C. rhizosoleniae cells to assist in buoyancy regulation. Results suggest that the trichome lengths of C. rhizosoleniae and R. intracellularis might be regulated by their diatom hosts’ symbiotic styles and by ambient nutrients. Short trichome length might help C. rhizosoleniae and R. intracellularis to stay in the euphotic zone regardless as to whether they are free-living or symbiotic

    Nondestructive quantitative analysis of water potential of tomato leaves using online hyperspectral imaging system

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    Tomatoes have different water requirements in each growing period. Excessive water use or insufficient water supply will affect the growth and yield of tomato plants. Therefore, precise irrigation control is necessary during cultivation to increase crop productivity. Traditionally, the soil moisture content or leaf water potential has been used as an indicator of plant water status. These methods, however, have limited accuracy and are time-consuming, making it difficult to be put into practice in tomato production. This study developed an online hyperspectral imaging system to measure the leaf water potential of tomato nondestructively. Linear Discriminant Analysis was utilized to automatically and quickly extract the leaf images, with the recognition accuracy of 94.68% was achieved. The mathematical processing of Standard Normal Variate scattering correction was used to remove the spectral variations caused by the defocused leave images. The developed leaf water potential prediction model based on the spectral image information attained using the developed system achieved the standard error of calibration of 0.201, coefficient of determination in calibration set of 0.814 and standard error of cross�validation of 0.230, and one minus the variance ratio of 0.755. The obtained performance indicated the feasibility of apply�ing the developed online hyperspectral imaging system as a real-time non-destructive measurement technique for the leaf water potential of tomato plants

    Modified empirical fitting of the discharge behavior of LiFePO4_4 batteries under various conditions

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    A mathematical model is developed by fitting the discharge curve of a new LiFePO4_4 battery and then used to investigate the relationship between the discharge time and the closed-circuit voltage. This model consists of exponential and polynomial terms where the exponential term dominates the discharge time of a battery and the polynomial term dominates the change in the closed-circuit voltage. Time shift and time scale processes modify the exponential and polynomial terms, respectively, so that the model is suitable for batteries under various conditions. References W. Su, H. Eichi, W. Zeng and M.-Y. Chow, A survey on the electrification of transportation in a smart grid environment, IEEE Intl. Conf. Ind. I. 8:1&ndash;10, 2012. doi:10.1109/TII.2011.2172454 J. Wang, Z. Sun and X. Wei, Performance and characteristic research in LiFePO4_4 battery for electric vehicle applications, IEEE Vehicle Power 1657&ndash;1661, 2009. doi:10.1109/VPPC.2009.5289664 A. Shafiei, A. Momeni and S. S. Williamson, Battery modeling approaches and management techniques for plug-in hybrid electric vehicles, IEEE Vehicle Power 1&ndash;5, 2011. doi:10.1109/VPPC.2011.6043191 P. Bai, D. A. Cogswell and M. Z. Bazant, Suppression of phase separation in LiFePO4_4 nanoparticles during battery discharge, Nano Lett. 11:4890&ndash;4896, 2011. doi:10.1021/nl202764f H. L. Chan and D. Sutanto, A new battery model for use with battery energy storage systems and electric vehicle power systems, IEEE Power Eng. Soc. 1:470&ndash;475, 2000. doi:10.1109/PESW.2000.850009 T. Kim and W. Qiao, A hybrid battery model capable of capturing dynamic circuit characteristics and nonlinear capacity effects, IEEE T. Energy Conver. 26:1172&ndash;1180, 2011. doi:10.1109/TEC.2011.2167014 D. N. Rakhmatov and S. B. K. Vrudhula, An analytical high-level battery model for use in energy management of portable electronic systems, IEEE ICCAD 488&ndash;493, 2001. doi:10.1109/ICCAD.2001.968687 V. Srinivasan and J. Newman, Discharge model for the lithium iron-phosphate electrode, J. Electrochem. Soc. 151:A1517&ndash;A1529, 2004. doi:10.1149/1.1785012 V. Rao, G. Singhal, A. Kumar and N. Navet, Battery model for embedded systems, VLSI Des. 105&ndash;110, 2005. doi:10.1109/ICVD.2005.61 S. Dargavillez and T. W. Farrell, Predicting active material utilization in LiFePO4_4 electrodes using a multiscale mathematical model, J. Electrochem. Soc. 157:A830&ndash;A840, 2010. doi:10.1149/1.3425620 R. Rao, S. Vrudhula and D. N. Rakhmatov, Battery modeling for energy-aware system design, Computer 36:77&ndash;87, 2003. doi:10.1109/MC.2003.1250886 M. Chen and G. A. Rincon-Mora, Accurate electrical battery model capable of predicting runtime and i-v performance, IEEE T. Energy Conver. 21:504&ndash;511, 2006. doi:10.1109/TEC.2006.874229 L. Gao, S. Liu and R. A. Dougal, Dynamic lithium-ion battery model for system simulation, IEEE T. Compon. Pack. T. 25:495&ndash;505, 2002. doi:10.1109/TCAPT.2002.803653 V. Agarwal, K. Uthaichana, R. A. DeCarlo and L. H. Tsoukalas, Development and validation of a battery model useful for discharging and charging power control and lifetime estimation, IEEE T. Energy Conver. 25:821&ndash;835, 2010. doi:10.1109/TEC.2010.2043106 B. Schweighofer, K. M. Raab and G. Brasseur, Modeling of high power automotive batteries by the use of an automated test system, IEEE T. Instrum. Meas. 52:1087&ndash;1091, 2003. doi:10.1109/TIM.2003.81482
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