49 research outputs found
Shoaling of large-amplitude nonlinear internal waves at Dongsha Atoll in the northern South China Sea
Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 37 (2012): 1-7, doi:10.1016/j.csr.2012.01.010.Shoaling of large-amplitude (~100 m) nonlinear internal waves over a steep slope (~3°) in water depths between 100 m and 285 m near Dongsha Atoll in the northern South China Sea is examined with an intensive array of thermistor moorings and a bottom mounted Acoustic Doppler Current Profiler. During the 44 h study period in May 5–7, 2008, there were four groups of large internal waves with semidiurnal modulation. In each wave group a rapid transition occurred during the shoaling, such that the front face of the leading depression wave elongated and plunged to the bottom and the rear face steepened and transformed into a bottom-trapped elevation wave. The transitions occur in water depths of 200 m and deeper, and represent the largest documented internal wave shoaling events. The observations repeatedly capture the detailed temperature and velocity structures of the incident plunging waves. Strong horizontal convergence and intense upward motion are found at the leading edge of transformed elevation waves, suggesting flow separation near the bottom. The observations are compared with the previous observations and model studies. The implication of the shoaling internal waves on coral reef ecology also is discussed.Support for LS and HS came from the US Office of Naval Researc
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Energy Flux and Dissipation in Luzon Strait: Two Tales of Two Ridges
Internal tide generation, propagation, and dissipation are investigated in Luzon Strait, a system of two quasi-parallel ridges situated between Taiwan and the Philippines. Two profiling moorings deployed for about 20 days and a set of nineteen 36-h lowered ADCP–CTD time series stations allowed separate measurement of diurnal and semidiurnal internal tide signals. Measurements were concentrated on a northern line, where the ridge spacing was approximately equal to the mode-1 wavelength for semidiurnal motions, and a southern line, where the spacing was approximately two-thirds that. The authors contrast the two sites to emphasize the potential importance of resonance between generation sites. Throughout Luzon Strait, baroclinic energy, energy fluxes, and turbulent dissipation were some of the strongest ever measured. Peak-to-peak baroclinic velocity and vertical displacements often exceeded 2 m s⁻¹ and 300 m, respectively. Energy fluxes exceeding 60 kW m⁻¹ were measured at spring tide at the western end of the southern line. On the northern line, where the western ridge generates appreciable eastward-moving signals, net energy flux between the ridges was much smaller, exhibiting a nearly standing wave pattern. Overturns tens to hundreds of meters high were observed at almost all stations. Associated dissipation was elevated in the bottom 500–1000 m but was strongest by far atop the western ridge on the northern line, where >500-m overturns resulted in dissipation exceeding 2 × 10⁻⁶ W kg⁻¹ (implying diapycnal diffusivity K[subscript]ρ > 0.2 m² s⁻¹). Integrated dissipation at this location is comparable to conversion and flux divergence terms in the energy budget. The authors speculate that resonance between the two ridges may partly explain the energetic motions and heightened dissipation.Keywords: Internal waves, MixingKeywords: Internal waves, Mixin
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Energy Flux and Dissipation in Luzon Strait: Two Tales of Two Ridges
Internal tide generation, propagation, and dissipation are investigated in Luzon Strait, a system of two quasi-parallel ridges situated between Taiwan and the Philippines. Two profiling moorings deployed for about 20 days and a set of nineteen 36-h lowered ADCP-CTD time series stations allowed separate measurement of diurnal and semidiurnal internal tide signals. Measurements were concentrated on a northern line, where the ridge spacing was approximately equal to the mode-1 wavelength for semidiurnal motions, and a southern line, where the spacing was approximately two-thirds that. The authors contrast the two sites to emphasize the potential importance of resonance between generation sites. Throughout Luzon Strait, baroclinic energy, energy fluxes, and turbulent dissipation were some of the strongest ever measured. Peak-to-peak baroclinic velocity and vertical displacements often exceeded 2 m s⁻¹ and 300 m, respectively. Energy fluxes exceeding 60 kW m⁻¹ were measured at spring tide at the western end of the southern line. On the northern line, where the western ridge generates appreciable eastward-moving signals, net energy flux between the ridges was much smaller, exhibiting a nearly standing wave pattern. Overturns tens to hundreds of meters high were observed at almost all stations. Associated dissipation was elevated in the bottom 500-1000 m but was strongest by far atop the western ridge on the northern line, where >500-m overturns resulted in dissipation exceeding 2 x 10⁻⁶ W kg⁻¹ (implying diapycnal diffusivity K[subscript p] > 0.2 m² s⁻¹). Integrated dissipation at this location is comparable to conversion and flux divergence terms in the energy budget. The authors speculate that resonance between the two ridges may partly explain the energetic motions and heightened dissipation.Keywords: Propagation, South China sea, Generation, Hawaiian ridge, Turbulence, Topography, Model, Internal tide, Ocea
The Yuan-Tseh Lee Array for Microwave Background Anisotropy
The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) is the
first interferometer dedicated to studying the cosmic microwave background
(CMB) radiation at 3mm wavelength. The choice of 3mm was made to minimize the
contributions from foreground synchrotron radiation and Galactic dust emission.
The initial configuration of seven 0.6m telescopes mounted on a 6-m hexapod
platform was dedicated in October 2006 on Mauna Loa, Hawaii. Scientific
operations began with the detection of a number of clusters of galaxies via the
thermal Sunyaev-Zel'dovich effect. We compare our data with Subaru weak lensing
data in order to study the structure of dark matter. We also compare our data
with X-ray data in order to derive the Hubble constant.Comment: accepted for publication in ApJ (13 pages, 7 figures); a version with
high resolution figures available at
http://www.asiaa.sinica.edu.tw/~keiichi/upfiles/AMiBA7/pho_highreso.pd
Women with endometriosis have higher comorbidities: Analysis of domestic data in Taiwan
AbstractEndometriosis, defined by the presence of viable extrauterine endometrial glands and stroma, can grow or bleed cyclically, and possesses characteristics including a destructive, invasive, and metastatic nature. Since endometriosis may result in pelvic inflammation, adhesion, chronic pain, and infertility, and can progress to biologically malignant tumors, it is a long-term major health issue in women of reproductive age. In this review, we analyze the Taiwan domestic research addressing associations between endometriosis and other diseases. Concerning malignant tumors, we identified four studies on the links between endometriosis and ovarian cancer, one on breast cancer, two on endometrial cancer, one on colorectal cancer, and one on other malignancies, as well as one on associations between endometriosis and irritable bowel syndrome, one on links with migraine headache, three on links with pelvic inflammatory diseases, four on links with infertility, four on links with obesity, four on links with chronic liver disease, four on links with rheumatoid arthritis, four on links with chronic renal disease, five on links with diabetes mellitus, and five on links with cardiovascular diseases (hypertension, hyperlipidemia, etc.). The data available to date support that women with endometriosis might be at risk of some chronic illnesses and certain malignancies, although we consider the evidence for some comorbidities to be of low quality, for example, the association between colon cancer and adenomyosis/endometriosis. We still believe that the risk of comorbidity might be higher in women with endometriosis than that we supposed before. More research is needed to determine whether women with endometriosis are really at risk of these comorbidities
Multisensory games-based learning - lessons learnt from olfactory enhancement of a digital board game
Serious games are becoming an alternative educational method in a variety of fields because of their potential to improve the quality of learning experiences and to facilitate knowledge acquisition and content understanding. Moreover, entertainment-driven learners are more easily motivated to benefit from the learning process through meaningful activities defined in a game context. Interfacing educational computer games with multisensorial interfaces allows for a seamless integration between virtual and physical environments. Multisensorial cues can improve memory and attention and increase the cognitive and sensory-motor performance. Despite of the increasing knowledge in sensory processes, multisensory experiences and interactions in computer based instruction remain insufficiently explored and understood. In this paper, we present a multisensory educational game - Fragrance Channel - and we investigate how enabling olfaction can contribute to users' learning performance, engagement and quality of experience. We compare results obtained after experiencing Fragrance Channel in the presence and absence of olfactory feedback on both a mobile and a PC. A knowledge test administered before and immediately after showed that our proposed educational game led to an improvement of performance in all the explored conditions. Subjective measurements carried out after the olfactory experience showed that students enjoyed the scenario and appreciated it as being relevant.European Union’s Horizon 2020 Research and Innovation programm
The formation and fate of internal waves in the South China Sea
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature 521 (2015): 65-69, doi:10.1038/nature14399.Internal gravity waves, the subsurface analogue of the familiar surface gravity
waves that break on beaches, are ubiquitous in the ocean. Because of their strong vertical and horizontal currents, and the turbulent mixing caused by their
breaking, they impact a panoply of ocean processes, such as the supply of nutrients
for photosynthesis1, sediment and pollutant transport2 and acoustic transmission3;
they also pose hazards for manmade structures in the ocean4. Generated primarily
by the wind and the tides, internal waves can travel thousands of kilometres from
their sources before breaking5, posing severe challenges for their observation and
their inclusion in numerical climate models, which are sensitive to their effects6-7.
Over a decade of studies8-11 have targeted the South China Sea, where the oceans’
most powerful internal waves are generated in the Luzon Strait and steepen
dramatically as they propagate west. Confusion has persisted regarding their
generation mechanism, variability and energy budget, however, due to the lack of
in-situ data from the Luzon Strait, where extreme flow conditions make
measurements challenging. Here we employ new observations and numerical
models to (i) show that the waves begin as sinusoidal disturbances rather than
from sharp hydraulic phenomena, (ii) reveal the existence of >200-m-high
breaking internal waves in the generation region that give rise to turbulence levels
>10,000 times that in the open ocean, (iii) determine that the Kuroshio western
boundary current significantly refracts the internal wave field emanating from the
Luzon Strait, and (iv) demonstrate a factor-of-two agreement between modelled
and observed energy fluxes that enables the first observationally-supported energy
budget of the region. Together, these findings give a cradle-to-grave picture of
internal waves on a basin scale, which will support further improvements of their
representation in numerical climate predictions.Our work was supported by the U.S. Office of Naval Research and
the Taiwan National Science Council.2015-10-2
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The formation and fate of internal waves in the South China Sea
Internal gravity waves, the subsurface analogue of the familiar
surface gravity waves that break on beaches, are ubiquitous in
the ocean. Because of their strong vertical and horizontal currents,
and the turbulent mixing caused by their breaking, they affect a
panoply of ocean processes, such as the supply of nutrients for
photosynthesis¹, sediment and pollutant transport² and acoustic
transmission³; they also pose hazards for man-made structures in
the ocean⁴. Generated primarily by the wind and the tides, internal
waves can travel thousands of kilometres from their sources before
breaking⁵, making it challenging to observe them and to include
them in numerical climate models, which are sensitive to their
effects[superscript 6,7]. For over a decade, studies[superscript 8–11] have targeted the South
China Sea, where the oceans’ most powerful known internal waves
are generated in the Luzon Strait and steepen dramatically as they
propagate west. Confusion has persisted regarding their mechanism
of generation, variability and energy budget, however,
owing to the lack of in situ data from the Luzon Strait, where
extreme flow conditions make measurements difficult. Here we
use new observations and numerical models to (1) show that the
waves begin as sinusoidal disturbances rather than arising from
sharp hydraulic phenomena, (2) reveal the existence of >200-metre-high breaking internal waves in the region of generation
that give rise to turbulence levels >10,000 times that in the open
ocean, (3) determine that the Kuroshio western boundary current
noticeably refracts the internal wave field emanating from the
Luzon Strait, and (4) demonstrate a factor-of-two agreement
between modelled and observed energy fluxes, which allows us to
produce an observationally supported energy budget of the region.
Together, these findings give a cradle-to-grave picture of internal
waves on a basin scale, which will support further improvements of
their representation in numerical climate predictions
Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population
Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (P interaction = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications
Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population.
Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (Pinteraction = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications