Split representation in celestial holography

We develop a split representation for celestial amplitudes in celestial holography, by cutting internal lines of Feynman diagrams in Minkowski space. More explicitly, the bulk-to-bulk propagators associated with the internal lines are expressed as a product of two boundary-to-bulk propagators with a coinciding boundary point integrated over the celestial sphere. Applying this split representation, we compute the conformal partial wave and conformal block expansions of celestial four-point functions of massless scalars and photons on the Euclidean celestial sphere. In the $t$-channel massless scalar amplitude, we observe novel intermediate exchanges of staggered modules in the conformal block expansion.Comment: 76 page

A Modular Theory of Radical Pro Drop

Mandarin Chinese is said to be a radical pro-drop language, in the sense that verbal arguments in this language can be dropped rather freely. However, in this dissertation, I show that the omission of arguments in Mandarin Chinese is in fact constrained by various conditions. First, I demonstrate that the availability of a discourse topic is insufficient to license empty categories in Mandarin Chinese by showing that subject and object positions cannot be left empty at random. Some empty subject positions are neither true instances of nominal ellipsis nor variables bound by discourse topics; instead, they are a side effect of verb or vP movement followed by TP-ellipsis. Next, I address the issue of when objects can be "dropped" in Mandarin Chinese. I argue that structural parallelism built on verbal identity between sentences plays an important role in licensing `objectless' sentences. I propose that the mechanism responsible for the creation of such sentences is V-stranding VP-ellipsis rather than argument ellipsis. In the last part of this dissertation, I show that, although we cannot rely on the strength of discourse alone to account for empty categories, the concept of topic-hood is nevertheless implicated in the appearance of certain empty argument positions in sentences used in monologues. I claim that subject pro in Mandarin Chinese must have as its antecedent an element located in an A'-position, which can be overt or covert. In addition, I suggest that the differences between Italian, Japanese, and Mandarin Chinese with respect to the use of subject pro can be boiled down to the featural properties of the covert topic TOP preceding subject pro: this covert topic has inherently valued phi-features in Italian and Japanese, while its counterpart in Mandarin Chinese does not.Linguistic

Caffeine-Induced Global Reductions in Resting-State BOLD Connectivity Reflect Widespread Decreases in MEG Connectivity.

In resting-state functional magnetic resonance imaging (fMRI), the temporal correlation between spontaneous fluctuations of the blood oxygenation level dependent (BOLD) signal from different brain regions is used to assess functional connectivity. However, because the BOLD signal is an indirect measure of neuronal activity, its complex hemodynamic nature can complicate the interpretation of differences in connectivity that are observed across conditions or subjects. For example, prior studies have shown that caffeine leads to widespread reductions in BOLD connectivity but were not able to determine if neural or vascular factors were primarily responsible for the observed decrease. In this study, we used source-localized magnetoencephalography (MEG) in conjunction with fMRI to further examine the origins of the caffeine-induced changes in BOLD connectivity. We observed widespread and significant (p < 0.01) reductions in both MEG and fMRI connectivity measures, suggesting that decreases in the connectivity of resting-state neuro-electric power fluctuations were primarily responsible for the observed BOLD connectivity changes. The MEG connectivity decreases were most pronounced in the beta band. By demonstrating the similarity in MEG and fMRI based connectivity changes, these results provide evidence for the neural basis of resting-state fMRI networks and further support the potential of MEG as a tool to characterize resting-state connectivity

Distributed Indexing Schemes for k-Dominant Skyline Analytics on Uncertain Edge-IoT Data

Skyline queries typically search a Pareto-optimal set from a given data set to solve the corresponding multiobjective optimization problem. As the number of criteria increases, the skyline presumes excessive data items, which yield a meaningless result. To address this curse of dimensionality, we proposed a k-dominant skyline in which the number of skyline members was reduced by relaxing the restriction on the number of dimensions, considering the uncertainty of data. Specifically, each data item was associated with a probability of appearance, which represented the probability of becoming a member of the k-dominant skyline. As data items appear continuously in data streams, the corresponding k-dominant skyline may vary with time. Therefore, an effective and rapid mechanism of updating the k-dominant skyline becomes crucial. Herein, we proposed two time-efficient schemes, Middle Indexing (MI) and All Indexing (AI), for k-dominant skyline in distributed edge-computing environments, where irrelevant data items can be effectively excluded from the compute to reduce the processing duration. Furthermore, the proposed schemes were validated with extensive experimental simulations. The experimental results demonstrated that the proposed MI and AI schemes reduced the computation time by approximately 13% and 56%, respectively, compared with the existing method.Comment: 13 pages, 8 figures, 12 tables, to appear in IEEE Transactions on Emerging Topics in Computin

Numerical Analysis on Color Preference and Visual Comfort from Eye Tracking Technique

Color preferences in engineering are very important, and there exists relationship between color preference and visual comfort. In this study, there are thirty university students who participated in the experiment, supplemented by pre- and posttest questionnaires, which lasted about an hour. The main purpose of this study is to explore the visual effects of different color assignment with subjective color preferences via eye tracking technology. Eye-movement data through a nonlinear analysis detect slight differences in color preferences and visual comfort, suggesting effective physiological indicators as extensive future research discussed. Results found that the average pupil size of eye-movement indicators can effectively reflect the differences of color preferences and visual comfort. This study more confirmed that the subjective feeling will make people have misjudgment

Perforated Appendiceal Mucinous Cystadenoma Mimicking Ruptured Appendicitis With Abscess Formation: CT Imaging Features

AbstractWe describe the imaging features of a perforated appendiceal mucinous cystadenoma in a 72-year-old woman presenting with right lower quadrant abdominal pain, mimicking ruptured appendicitis with abscess formation. Computed tomography revealed a rim-enhanced cystic lesion at the proximal appendiceal orifice, connecting with the swollen and dilated distal part of the appendix. Disruption of the appendiceal walls and peri-appendiceal fatty infiltrations were also noted. Under the impression of ruptured appendicitis with abscess formation, the patient underwent exploratory laparotomy and appendectomy. The pathologic diagnosis was perforated appendiceal mucinous cystadenoma associated with superinfection, complicated by secondary appendicitis. The patient was uneventfully discharged on the 7th hospital day. Although primary neoplasms of the appendix are uncommon, they should be considered as a predisposing factor in elderly patients manifesting with appendicitis