The multiple merger assembly of a hyperluminous obscured quasar at redshift 4.6

Dí,az-Santos, T.,Assef, R. J.,Blain, A. W.,Aravena, M.,Stern, D.,Tsai, C.-W.,Eisenhardt, P.,Wu, J.,Jun, H. D.,Dibert, K.,Inami, H.,Lansbury, G.,Leclercq, F. American Association for the Advancement of Scienc 2018 Science Vol.362 No.6418

<P><B>Mergers drive a powerful dusty quasar</B></P><P>Massive galaxies in the early Universe host supermassive black holes at their centers. When material falls toward the black hole, it releases energy and is observed as a quasar. Astronomers found a population of powerful distant quasars that are obscured by dust, but it has been unclear how they are formed. Díaz-Santos <I>et al.</I> observed the dust-obscured quasar WISE J224607.56-052634.9 at submillimeter wavelengths, finding three small companion galaxies connected to the quasar by bridges of gas and dust. They inferred that galaxy mergers can provide both the raw material to power a quasar and large quantities of dust to obscure it.</P><P><I>Science</I>, this issue p. 1034</P><P>Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56−052634.9 (W2246−0526), a dust-obscured quasar at redshift 4.6, 1.3 billion years after the Big Bang. Far-infrared dust continuum observations show three galaxy companions around W2246−0526 with disturbed morphologies, connected by streams of dust likely produced by the dynamical interaction. The detection of tidal dusty bridges shows that W2246−0526 is accreting its neighbors, suggesting that merger activity may be a dominant mechanism through which the most luminous galaxies simultaneously obscure and feed their central supermassive black holes.</P>

Using Frequency Domain Reflectometry for Rapidly Measurement of Peanut Moisture Content

( C. J. Hsu ),( C. C. Hsu ),( H. K. Lee ),( T. M. Chen ),( P. K. Lei ),( Y. C. Tsai ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In order to achieve rapidly measurement of peanut moisture content, the Frequency Domain Reflectometry (FDR) system was designed and develop by combining a dual-probe frequency domain reflectometer and Latte Panda. For the peanut moisture content FDR measurement, the calibration curve is necessary to define at first. The peanut samples (Tainan No.9 and Tainan No.18) are separate into pods and kernels and pulverized into granule shape for the measurement. The samples are baked in the oven at 130°C for 6 hours for removing the water content and defined it as 0% moisture content. Then the different weights of water have been added into samples for making different moisture content peanuts. The different dielectric constant measured by FDR sensor system is corresponded as the different moisture content. The calibration curve can be obtained from the relationship between the different moisture content peanut samples and the corresponding dielectric constant. During the FDR measurement, 32 N/㎡ applying force to the sample is necessary for eliminating the air gap. Furthermore, different methods for measuring the peanut moisture content were carried out in the factory with the drying machine. The comparison and results of different measure methods during the drying process at factory has been completed. The result shows that different measuring method have the same peanut moisture content trend. In addition, another method for obtaining the calibration curve was carried out in this work. The peanuts were baked to different moisture content and measured the corresponding dielectric constant. The calibration curves of peanut’s pods and kernels and the accuracy test has been defined. The both correlation coefficients of the testing samples are more than 0.97. It proves that this proposal FDR system have high accuracy and is enable to rapidly measure from 5% to 60% moisture content of peanut.

High Temperature Oxidation Behavior of Nickel and Iron Based Superalloys in Helium Containing Trace Impurities

( C. J. Tsai ),( T. K. Yeh ),( M. Y. Wang ) 한국부식방식학회(구 한국부식학회) 2019 Corrosion Science and Technology Vol.18 No.1

A high-temperature gas-cooled reactor (HTGR) is recognized as the best candidate reactor for next generation nuclear reactors. Helium is used to be the coolant in the core of the HTGR with temperature expected to exceed 900 °C at the core outlet. Several iron- and nickel-based superalloys, including Alloy 800H, Hastelloy X, and Alloy 617, are potential structural materials for intermediate heat exchanger (IHX) in an HTGR. Oxidation behaviors of three selected alloys (Hastelloy X, Alloy 800H, and Alloy 617) were investigated at four different temperatures from 650℃ to 950 ℃ under helium environments with various concentrations of O₂ and H₂O. Preliminary results showed that chromium oxide as the primary protective layer was observed on surfaces of the three tested alloys. Based on results of mass gain and SEM analyses, Hastelloy X alloy exhibited the best corrosion resistance in all corrosion tests. Further details on the oxidation mechanism of these alloys are presented in this study.

Robust, Tunable Biological Oscillations from Interlinked Positive and Negative Feedback Loops

Tsai, T. Y.-C.,Choi, Y. S.,Ma, W.,Pomerening, J. R.,Tang, C.,Ferrell, J. E. American Association for the Advancement of Scienc 2008 Science Vol.321 No.5885

<P>A simple negative feedback loop of interacting genes or proteins has the potential to generate sustained oscillations. However, many biological oscillators also have a positive feedback loop, raising the question of what advantages the extra loop imparts. Through computational studies, we show that it is generally difficult to adjust a negative feedback oscillator's frequency without compromising its amplitude, whereas with positive-plus-negative feedback, one can achieve a widely tunable frequency and near-constant amplitude. This tunability makes the latter design suitable for biological rhythms like heartbeats and cell cycles that need to provide a constant output over a range of frequencies. Positive-plus-negative oscillators also appear to be more robust and easier to evolve, rationalizing why they are found in contexts where an adjustable frequency is unimportant.</P>

Optical characteristics of silver film on the moth-eye structure

C. J. Ting,H. Y. Tsai,C. P. Chou,H. Y. Lin,T. C. Wu 대한기계학회 2007 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.21 No.10

FLUORIDE REMOVAL FROM WATER WITH IRON - COATED SPENT CATALYST

( C . Y . Tsai,J . C . Liu ) 한국물환경학회 1997 제6차 국제수질보전학회 아시아 태평양지역 학술회의 Vol.2 No.-

The X-Pt(X=Ge, Cr) Underlayer Thickness Effect on Magnetic Properties of L1₀ FePt Films

J. L. Tsai,Y. C. Lin,C. J. Hsu,C. W. Hsu,S. K. Chen,W. C. Chang 한국자기학회 2007 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Effects of fermented soybean meal with Bacillus velezensis, Lactobacillus spp. or their combination on broiler performance, gut antioxidant activity and microflora

Tsai, C.F.,Lin, L.J.,Wang, C.H.,Tsai, C.S.,Chang, S.C.,Lee, T.T. Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.12

Objective: A series of experiment were conducted to evaluate the effects of replacing a part of soybean meal (SBM) at 6% of broiler diets with fermented soybean meal (FSBM) obtained by single or two-stage fermentation by measuring growth performance, antioxidant activity in the jejunum and distal intestinal microflora. Methods: Soybean meal samples were prepared by single-stage fermentation using Bacillus velezensis (Bv) (FSBM_B), or Lactobacillus spp. (as commercial control) (FSBM_L). Additional SBM sample was prepared by two-stage fermentation using Bv and subsequently using Lactobacillus brevis ATCC 367 (Lb) (FSBM_B+L). Enzyme activity, chemical composition, trichloroethanoic acid-nitrogen solubility index (TCA-NSI) and antioxidant activity were measured. Then, in an in vivo study, 320 Ross308 broilers were divided into four groups with ad libitum supply of feed and water. Four groups were fed either a corn-soybean meal diet (SBM), or one of fermented SBM diets (FSBM_B+L, FSBM_B, and FSBM_L). Growth, serum characteristics, microflora, and the mRNA expression of selected genes were measured. Results: Compared to SBM, FSBM_B+L contained lower galacto-oligosaccharide, allergic protein, and trypsin inhibitor, and higher TCA-NSI by about three times (p<0.05). Reducing power and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging ability correlated positively with the TCA-NSI content in FSBM. Growth performances were not significantly different among four groups. In jejunum of 35-day-old broilers, partial replacement of SBM by FSBM_B+L increased the activity of superoxide dismutase and catalase (CAT), and the FSBM_B group had the highest catalase activity (p<0.05). Partial replacement of SBM by FSBM increased relative mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and peptide transporter 1 (PepT1) (p<0.05); however, FSBM_B+L increased CAT mRNA level to 5 times of the control (p<0.05). Conclusion: Using Bv- and Lb-processed SBM through two-stage fermentation to partially replace 6% of diets will improve the gut's antioxidant activity under commercial breeding in broilers.

Area-preserving scheme for efficiency enhancement in single-pass tapered free electron lasers

Tsai, C.-Y.,Emma, C.,Wu, J.,Yoon, M.,Wang, X.,Yang, C.,Zhou, G. Elsevier 2019 Nuclear Instruments & Methods in Physics Research. Vol.913 No.-

<P><B>Abstract</B></P> <P>Efficiency enhancement of a single-pass short-wavelength high-gain tapered free electron laser (FEL) has recently been intensively studied. The goal is to sustain the growth of radiation power in the post-saturation regime. Among the various schemes, the undulator tapering is considered an effective route to achieve higher power extraction efficiency. The tapering strategy can be of constant or varying resonant phase along the undulator axis. In this paper we propose an efficiency-enhancement scheme based on preservation of the longitudinal phase space area which ensures trapping of resonant particles in the ponderomotive bucket as long as possible along the undulator axis before significant particle depletion occurs. In the meanwhile such a scheme takes advantage of the increase of the radiation field amplitude to precipitate the particle deceleration process at the middle stage of undulator tapering. We analyze such an area-preserving scheme of undulator tapering by formulating the post-saturation FEL interaction in a one-dimensional (1-D) model via introduction of the particle trapping fraction. The output performance is evaluated through numerical iteration and confirmed with 1-D particle tracking simulations. The results show that the optimal power extraction efficiency based on the proposed scheme, together with a prebunched beam, can be greatly improved within relatively short taper length compared with other schemes before radiation diffraction effect becomes significant. Besides, the undesired sideband effects are found to be effectively suppressed. For the proposed area-preserving taper scheme, we also derive an analytical approximate formula for the resonant phase as a function of undulator axis. We expect that the analysis can shed light on the aim to further enhance the power extraction efficiency in single-pass tapered FELs.</P>

Bone Drilling System for Quantifying Hand Feeling in Orthopedic Surgery

( C. -y. Wu ),( J. -y. Su ),( C. -s. Hsu ),( Y. -h. Chen ),( K. -f. Chang ),( C. -c. Huang ),( H. -m. Wu ),( Y. -c. Tsai ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In this work, a bone drilling system was designed to quantify “hand feeling”, which can benefit surgeons to be more acquainted with bone hardness. A bi-axial force/torque sensor is mounted on the bone drilling system in order to measure the thrust force and the torque caused by drilling in bones. The system is assembled with a motorized stage, which is directly integrated with a surgical handpiece by an adjustable holder, to drill into various bones (porcine mandible, porcine femur, porcine rib) at different feed speeds and spindle speeds. The results reveal that the feed speed is positively corresponded with force and torque. However, the effect of spindle speed on force and torque is negligible. In addition, drilling bones without spraying water can cause the drilling temperature to increase to 73.3°C. According to the data from the experiments, the exact force and torque during bone drilling can be predicted with the given parameters. Thus, surgeons are capable of preventing the use of excessive force during bone drilling.