4,748 research outputs found
The Impact of Organizational Coordination and Climate on Marketing Executives\u27 Satisfaction with Information Systems Services
Information system (IS) managers rely on a number of devices to improve performance and the perception of performance on the part of the user. These techniques can be a variety of tools and organizational structures put in place by various levels of management. Horizontal coordination activities are such a device, one that is intended to improve the communication between users and IS developers. Past research has found an impact of coordination on IS success. However, the climate, general attitudes about the IS function in an organization in which the developers and users operate, can serve as an important moderator. Analysis of a sample of marketing executives indicates that the climate is an important moderator and may impact the ability of structural features to improve perceived performance. Managers must consider the climate as an important feature
Prompt-augmented Temporal Point Process for Streaming Event Sequence
Neural Temporal Point Processes (TPPs) are the prevalent paradigm for
modeling continuous-time event sequences, such as user activities on the web
and financial transactions. In real-world applications, event data is typically
received in a \emph{streaming} manner, where the distribution of patterns may
shift over time. Additionally, \emph{privacy and memory constraints} are
commonly observed in practical scenarios, further compounding the challenges.
Therefore, the continuous monitoring of a TPP to learn the streaming event
sequence is an important yet under-explored problem. Our work paper addresses
this challenge by adopting Continual Learning (CL), which makes the model
capable of continuously learning a sequence of tasks without catastrophic
forgetting under realistic constraints. Correspondingly, we propose a simple
yet effective framework, PromptTPP\footnote{Our code is available at {\small
\url{ https://github.com/yanyanSann/PromptTPP}}}, by integrating the base TPP
with a continuous-time retrieval prompt pool. The prompts, small learnable
parameters, are stored in a memory space and jointly optimized with the base
TPP, ensuring that the model learns event streams sequentially without
buffering past examples or task-specific attributes. We present a novel and
realistic experimental setup for modeling event streams, where PromptTPP
consistently achieves state-of-the-art performance across three real user
behavior datasets.Comment: NeurIPS 2023 camera ready versio
Nature of exciton transitions in hexagonal boron nitride
Citation: Li, J., Cao, X. K., Hoffman, T. B., Edgar, J. H., Lin, J. Y., & Jiang, H. X. (2016). Nature of exciton transitions in hexagonal boron nitride. Applied Physics Letters, 108(12), 4. doi:10.1063/1.4944696In contrast to other III-nitride semiconductors GaN and AlN, the intrinsic (or free) exciton transition in hexagonal boron nitride (h-BN) consists of rather complex fine spectral features (resolved into six sharp emission peaks) and the origin of which is still unclear. Here, the free exciton transition (FX) in h-BN bulk crystals synthesized by a solution method at atmospheric pressure has been probed by deep UV time-resolved photoluminescence (PL) spectroscopy. Based on the separations between the energy peak positions of the FX emission lines, the identical PL decay kinetics among different FX emission lines, and the known phonon modes in h-BN, we suggest that there is only one principal emission line corresponding to the direct intrinsic FX transition in h-BN, whereas all other fine features are a result of phonon-assisted transitions. The identified phonon modes are all associated with the center of the Brillouin zone. Our results offer a simple picture for the understanding of the fundamental exciton transitions in h-BN. (C) 2016 AIP Publishing LLC
Acoustic multipath arrivals in the horizontal plane due to approaching nonlinear internal waves
Author Posting. © Acoustical Society of America, 2011. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 129 (2011): EL141-EL147, doi:10.1121/1.3553374.Simultaneous measurements of acoustic wave transmissions and a nonlinear internal wave packet approaching an along-shelf acoustic path during the Shallow Water 2006 experiment are reported. The incoming internal wave packet acts as a moving frontal layer reflecting (or refracting) sound in the horizontal plane. Received acoustic signals are filtered into acoustic normal mode arrivals. It is shown that a horizontal multipath interference is produced. This has previously been called a horizontal Lloyd’s mirror. The interference between the direct path and the refracted path depends on the mode number and frequency of the acoustic signal. A mechanism for the multipath interference is shown. Preliminary modeling results of this dynamic interaction using vertical modes and horizontal parabolic equation models are in good agreement with the observed data
Rb and p130 control cell cycle gene silencing to maintain the postmitotic phenotype in cardiac myocytes
Both Rb and p130 are required for the recruitment of heterochromatin proteins that mediate silencing of proliferation genes in adult cardiac myocytes
Enhancing Event Sequence Modeling with Contrastive Relational Inference
Neural temporal point processes(TPPs) have shown promise for modeling
continuous-time event sequences. However, capturing the interactions between
events is challenging yet critical for performing inference tasks like
forecasting on event sequence data. Existing TPP models have focused on
parameterizing the conditional distribution of future events but struggle to
model event interactions. In this paper, we propose a novel approach that
leverages Neural Relational Inference (NRI) to learn a relation graph that
infers interactions while simultaneously learning the dynamics patterns from
observational data. Our approach, the Contrastive Relational Inference-based
Hawkes Process (CRIHP), reasons about event interactions under a variational
inference framework. It utilizes intensity-based learning to search for
prototype paths to contrast relationship constraints. Extensive experiments on
three real-world datasets demonstrate the effectiveness of our model in
capturing event interactions for event sequence modeling tasks.Comment: 6 pages, 2 figure
A multi-institutional study evaluating and describing atypical parathyroid tumors discovered after parathyroidectomy
Objective: To describe common intraoperative and pathologic findings of atypical parathyroid tumors (APTs) and evaluate clinical outcomes in patients undergoing parathyroidectomy.
Methods: In this multi-institutional retrospective case series, data were collected from patients who underwent parathyroidectomy from 2000 to 2018 from three tertiary care institutions. APTs were defined according to the AJCC eighth edition guidelines and retrospective chart review was performed to evaluate the incidence of recurrent laryngeal nerve injury, recurrence of disease, and disease-specific mortality.
Results: Twenty-eight patients were identified with a histopathologic diagnosis of atypical tumor. Mean age was 56 years (range, 23-83) and 68% (19/28) were female. All patients had an initial diagnosis of primary hyperparathyroidism with 21% (6/28) exhibiting clinical loss of bone density and 32% (9/28) presenting with nephrolithiasis or renal dysfunction. Intraoperatively, 29% (8/28) required thyroid lobectomy, 29% (8/28) had gross adherence to adjacent structures and 46% (13/28) had RLN adherence. The most common pathologic finding was fibrosis 46% (13/28). Postoperative complications include RLN paresis/paralysis in 14% (4/28) and hungry bone syndrome in 7% (2/28). No patients with a diagnosis of atypical tumor developed recurrent disease, however there was one patient that had persistent disease and hypercalcemia that is being observed. There were 96% (27/28) patients alive at last follow-up, with one death unrelated to disease.
Conclusion: Despite the new AJCC categorization of atypical tumors staged as Tis, we observed no recurrence of disease after resection and no disease-specific mortality. However, patients with atypical tumors may be at increased risk for recurrent laryngeal nerve injury and incomplete resection
Disorder-Driven Pretransitional Tweed in Martensitic Transformations
Defying the conventional wisdom regarding first--order transitions, {\it
solid--solid displacive transformations} are often accompanied by pronounced
pretransitional phenomena. Generally, these phenomena are indicative of some
mesoscopic lattice deformation that ``anticipates'' the upcoming phase
transition. Among these precursive effects is the observation of the so-called
``tweed'' pattern in transmission electron microscopy in a wide variety of
materials. We have investigated the tweed deformation in a two dimensional
model system, and found that it arises because the compositional disorder
intrinsic to any alloy conspires with the natural geometric constraints of the
lattice to produce a frustrated, glassy phase. The predicted phase diagram and
glassy behavior have been verified by numerical simulations, and diffraction
patterns of simulated systems are found to compare well with experimental data.
Analytically comparing to alternative models of strain-disorder coupling, we
show that the present model best accounts for experimental observations.Comment: 43 pages in TeX, plus figures. Most figures supplied separately in
uuencoded format. Three other figures available via anonymous ftp
Immune Amplification of Murine CD8+ Suppressor T Cells Induced via An Immune-Privileged Site: Quantifying Suppressor T Cells Functionally
BACKGROUND: CD8(+) suppressor T cells exert antigen-specific suppression of the expression of hypersensitivity by activated T cells. Therefore, CD8(+) suppressor T cells serve a major regulatory role for the control of active immunity. Accordingly, the number and/or activity of CD8(+) suppressor T cells should be influenced by an immune response to the antigen. To test this hypothesis we used an adoptive transfer assay that measures the suppression of the expression of delayed-type hypersensitivity (DTH) by CD8(+) suppressor T cells to quantify the antigen-specific suppression of DTH by these suppressor T cells. METHODS: Suppressor T cells were induced in the spleens of mice by the injection of antigen into the anterior chamber of an eye. Following this injection, the mice were immunized by the same antigen injected into the anterior chamber. Spleen cells recovered from these mice (AC-SPL cells) were titrated in an adoptive transfer assay to determine the number of AC-SPL cells required to effect a 50% reduction of antigen-induced swelling (Sw50) in the footpad of immunized mice challenged by antigen. RESULTS: Suppression of the expression of DTH is proportional to the number of AC-SPL cells injected into the site challenged by antigen. The number of AC-SPL cells required for a 50% reduction in DTH-induced swelling is reduced by injecting a cell population enriched for CD8(+) AC-SPL cells. Immunizing the mice receiving intracameral antigen to the same antigen decreases the RSw50 of AC-SPL cells required to inhibit the expression of DTH. CONCLUSIONS: The results provide the first quantitative demonstration that the numbers of antigen-specific splenic CD8(+) suppressor T cells are specifically amplified by antigen during an immune response
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