4,136 research outputs found
A STUDY ON TRAVEL INFORMATION ADOPTION INTENTION IN THE ONLINE SOCIAL COMMUNITY: THE PERSPECTIVES OF CUSTOMER EXPERIENCE AND INFORMATION ADOPTION MODEL
With the popularity of the online social community, people have become accustomed to sharing their travel experiences online. Internet users can read about othersā experiences, view tour photos, and gather information from other users during their leisure time or before travelling abroad. This study based on the information adoption theory and the concept of experience marketing; additionally, the moderating effects of consumption point on association among customer experiences, information usefulness, and information adoption intentions has been investigated. An Internet survey was conducted for data collection, and 492 returned responses were analyzed. The findings show that customer experience and information usefulness increase Internet usersā information adoption intentions and that the quality and credibility of Internet tourism information have a positive effect on customer experience and information usefulness. Content vividness was linked to an improved user experience. Consumption point influences the relationship between information usefulness and information adoption intentions, but it does not affect the relationship between customer experience and information adoption intention
Decreased influence of Antarctic intermediate water in the tropical Atlantic during North Atlantic cold events
Ā© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Earth and Planetary Science Letters 389 (2014): 200-208, doi:10.1016/j.epsl.2013.12.037.Antarctic Intermediate Water (AAIW) is a key player in the global ocean circulation, contributing to the upper limb of the Atlantic Meridional Overturning Circulation (AMOC), and influencing interhemispheric heat exchange and the distribution of salinity, nutrients and carbon. However, the deglacial history of AAIW flow into the North Atlantic is controversial. Here we present a multicore-top neodymium isotope calibration, which confirms the ability of unclean foraminifera to faithfully record bottom water neodymium isotopic composition (ĪµNdĪµNd) values in their authigenic coatings. We then present the first foraminifera-based reconstruction of ĪµNdĪµNd from three sediment cores retrieved from within modern AAIW, in the western tropical North Atlantic. Our records reveal similar glacial and interglacial contributions of AAIW, and a pronounced decrease in the AAIW fraction during North Atlantic deglacial cold episodes, Heinrich Stadial 1 (HS1) and Younger Dryas (YD). Our results suggest two separate phases of reduced fraction of AAIW in the tropical Atlantic during HS1, with a greater reduction during early HS1. If a reduction in AAIW fraction also reflects reduced AMOC strength, this finding may explain why, in many regions, there are two phases of hydrologic change within HS1, and why atmospheric CO2 rose more rapidly during early than late HS1. Our result suggesting less flow of AAIW into the Atlantic during North Atlantic cold events contrasts with evidence from the Pacific, where intermediate-depth ĪµNdĪµNd records may indicate increased flow of AAIW into the Pacific during the these same events. Antiphased ĪµNdĪµNd behavior between intermediate depths of the North Atlantic and Pacific implies that the flow of AAIW into Atlantic and Pacific seesawed during the last deglaciation.This work was supported by US NSF grants and a Lawrence J. Pratt and Melinda M. Hall Endowed Fund for Interdisciplinary Research Award to D.W.O. and W.B.C. and by a Taiwan NSC Postdoctoral Fellowship (NSC98-2917-I-564-132) to K.F.H
Nonhomogeneous seawater Sr isotopic composition in the coastal oceans : a novel tool for tracing water masses and submarine groundwater discharge
Author Posting. Ā© American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 12 (2011): Q05002, doi:10.1029/2010GC003372.Here we present high-precision (2Ļ = Ā±3 ppm) 87Sr/86Sr measurements in coastal waters, together with salinity, to evaluate water mass mixing and the influence of submarine groundwater discharge (SGD) in coastal waters and marginal seas. Nonhomogeneous Sr isotopic variations in water columns were documented in the Southern Okinawa Trough (SOT), South China Sea, and Kao-ping Canyon (KPC), where seawater 87Sr/86Sr varied up to 70 ppm. Seawater Sr isotopic composition changes only slightly in the upper 200 m of the SOT but was detectable and highly correlated with salinity, indicating a mixing between radiogenic North Pacific Tropical Water (high 87Sr/86Sr and high salinity) at 100ā150 m and a less radiogenic component with low 87Sr/86Sr and low salinity at ā¼200 m. Vertical profiles of seawater 87Sr/86Sr along the KPC show significant variations, suggesting dynamic mixing affected by continental inputs (i.e., river runoff and SGD) in this region. These results highlight the potential use of seawater Sr isotopes as a powerful tracer for determining mixing ratios and the dynamic mixing of oceanic water masses, especially in coastal and marginal seas.This
research was supported by a postdoctoral fellowship from Top
University (NCKU), Taiwan, to K.āF. Huang and funds from
NSC and MOE, Taiwan, to C.āF. You
Authenticity Preservation with Histogram-Based Reversible Data Hiding and Quadtree Concepts
With the widespread use of identification systems, establishing authenticity with sensors has become an important research issue. Among the schemes for making authenticity verification based on information security possible, reversible data hiding has attracted much attention during the past few years. With its characteristics of reversibility, the scheme is required to fulfill the goals from two aspects. On the one hand, at the encoder, the secret information needs to be embedded into the original image by some algorithms, such that the output image will resemble the input one as much as possible. On the other hand, at the decoder, both the secret information and the original image must be correctly extracted and recovered, and they should be identical to their embedding counterparts. Under the requirement of reversibility, for evaluating the performance of the data hiding algorithm, the output image quality, named imperceptibility, and the number of bits for embedding, called capacity, are the two key factors to access the effectiveness of the algorithm. Besides, the size of side information for making decoding possible should also be evaluated. Here we consider using the characteristics of original images for developing our method with better performance. In this paper, we propose an algorithm that has the ability to provide more capacity than conventional algorithms, with similar output image quality after embedding, and comparable side information produced. Simulation results demonstrate the applicability and better performance of our algorithm
Localized Langerhans cell histiocytosis masquerading as Brodie s abscess in a 2-year-old child: a case report
Langerhans cell histiocytosis (LCH), formerly known as histiocytosis X, refers to a spectrum of diseases characterized by idiopathic proliferation of histiocytes that produce either focal (localized LCH) or systemic manifestations (HandāSchĆ¼llerāChristian disease and LettererāSiwe disease). Localized LCH accounts for approximately 60ā70 % of all LCH cases. Osseous involvement is the most common manifestation and typically involves the flat bones, along with lesions of the skull, pelvis, and ribs. Localized LCH in bone shows a wide spectrum of clinical manifestations and radiologic features that may mimic those of infections as well as benign and malignant tumors. The diagnostic imaging findings of localized LCH are also diverse and challenging. The penumbra sign is a common and characteristic magnetic resonance imaging (MRI) feature of Brodieās abscess, but is rarely seen in localized LCH. In this report, we describe a case of localized LCH misdiagnosed as Brodieās abscess in a 2-year-old child based on clinical symptoms, laboratory findings, and pre-diagnostic MRI findings (penumbra sign). Therefore, the penumbra sign is not sufficient to clearly establish the diagnosis of Brodieās abscess, and the differential diagnosis of localized LCH should be considered when a child with an osteolytic lesion presents with a penumbra sign
Data constraints on glacial Atlantic Water mass geometry and properties
Ā© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Paleoceanography and Paleoclimatology 33 (2018): 1013-1034, doi:10.1029/2018PA003408.The chemical composition of benthic foraminifera from marine sediment cores provides information on how glacial subsurface water properties differed from modern, but separating the influence of changes in the origin and endāmember properties of subsurface water from changes in flows and mixing is challenging. Spatial gaps in coverage of glacial data add to the uncertainty. Here we present new data from cores collected from the Demerara Rise in the western tropical North Atlantic, including cores from the modern tropical phosphate maximum at Antarctic Intermediate Water (AAIW) depths. The results suggest lower phosphate concentration and higher carbonate saturation state within the phosphate maximum than modern despite similar carbon isotope values, consistent with less accumulation of respired nutrients and carbon, and reduced airāsea gas exchange in source waters to the region. An inversion of new and published glacial data confirms these inferences and further suggests that lower preformed nutrients in AAIW, and partial replacement of this still relatively highānutrient AAIW with nutrientādepleted, carbonateārich waters sourced from the region of the modernāday northern subtropics, also contributed to the observed changes. The results suggest that glacial preformed and remineralized phosphate were lower throughout the upper Atlantic, but deep phosphate concentration was higher. The inversion, which relies on the fidelity of the paleoceanographic data, suggests that the partial replacement of North Atlantic sourced deep water by Southern Ocean Water was largely responsible for the apparent deep North Atlantic phosphate increase, rather than greater remineralization.National Science Foundation (NSF) Grant Numbers: OCEā0750880, OCEā1335191, OCEā1558341, OCEā1536380;
Woods Hole Oceanographic Institution (WHOI) Grant Numbers: 27007592, 2700080
Vocal cord dysfunction diagnosed by four-dimensional dynamic volume computed tomography in patients with difficult-to-treat asthma: A case series
Patients with asthma may also have vocal cord dysfunction (VCD), which leads to poor control of the asthma. Once patients are diagnosed with difficult-to-treat asthma with poor control, VCD should be excluded or treated accordingly. The gold standard for diagnosis of VCD is to perform a laryngoscopy. However, this procedure is invasive and may not be suitable for patients with difficult-to-treat asthma. Four-dimensional (4D) dynamic volume computed tomography (CT) is a noninvasive method for quantification of laryngeal movement, and can serve as an alternative for the diagnosis of VCD. Herein, we present a series of five cases with difficult-to-treat asthma patients who were diagnosed with VCD by 4D dynamic volume CT. Clinicians should be alert to the possibility of VCD when poor control is noted in patients with asthma. Early diagnosis by noninvasive 4D dynamic volume CT can decrease excessive doses of inhaled corticosteroids
Special Invertebrate Models and Integrative Medical Applications: Regulations, Mechanisms, and Therapies
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