1,705 research outputs found
Robust Affinity Propagation using Preference Estimation
Affinity propagation is a novel unsupervised learning algorithm for exemplar-based clustering without the priori
knowledge of the number of clusters (NC). In this article, the influence of the “preference” on the accuracy of
AP output is addressed. We present a robust AP clustering method, which estimates what preference value could
possibly yield an optimal clustering result. To demonstrate the performance promotion, we apply the robust AP
on picture clustering, using local SIFT, global MPEG-7 CLD, and the proposed preference as the input of AP.
The experimental results show that over 40% enhancement of ARI accuracy for several image datasets
Phase and Amplitude Responses of Narrow-Band Optical Filter Measured by Microwave Network Analyzer
The phase and amplitude responses of a narrow-band optical filter are
measured simultaneously using a microwave network analyzer. The measurement is
based on an interferometric arrangement to split light into two paths and then
combine them. In one of the two paths, a Mach-Zehnder modulator generates two
tones without carrier and the narrow-band optical filter just passes through
one of the tones. The temperature and environmental variations are removed by
separated phase and amplitude averaging. The amplitude and phase responses of
the optical filter are measured to the resolution and accuracy of the network
analyzer
High-resolution Ultrasonography in Superficial Soft Tissue Tumors
Surgical removal and clinical follow-up of soft tissue masses are easily managed in clinical practice but are dependent on the experience of the clinician. Occasionally, however, a patient is referred from a local clinician to our clinic with an inoperable mass following a surgical procedure. We consider it important to fully understand the nature of the mass prior to surgery, thus avoiding unnecessary surgery in some cases. High-resolution ultrasonography has been widely applied in the musculoskeletal system over the past two decades and is very useful in evaluating the nature of superficial soft tissue masses. It enables the differentiation of benign and malignant masses and the detection of many different types of histology in superficial soft tissue masses. The purpose of this review is to demonstrate the characteristic findings of high-resolution ultrasonography and color Doppler ultrasonography in superficial soft tissue tumors
Correlation of histopathologic and dynamic tissue perfusion measurement findings in transplanted kidneys
BACKGROUND: Cortical perfusion of the renal transplant can be non-invasively assessed by color Doppler ultrasonography. We performed the Dynamic Tissue Perfusion Measurement (DTPM) of the transplant’s renal cortex using color Doppler ultrasonography (PixelFlux technique), and compared the results with the histopathological findings of transplant biopsies. METHODS: Ninety-six DTPM studies of the renal transplant’s cortex followed by transplant biopsies were performed in 78 patients. The cortical perfusion data were compared with the parameter of peritubular inflammatory cell accumulation (PTC 0 to 3) based on Banff-classification system. RESULTS: A significant decrease of cortical perfusion could be demonstrated as the inflammatory cells accumulation in peritubular capillaries increased. Increasing peritubulitis caused a perfusion loss from central to distal layers of 79% in PTC 0, of 85% in PTC 1, of 94% in PTC 2, and of 94% in PTC 3. Furthermore, the perfusion loss due to peritubular inflammation was more prominent in the distal cortical layer. The extent of perfusion decline with increasing peritubulitis (from PTC 0 to PTC 3) was 64% in proximal 20% cortical layer (p20), 63% in proximal 50% cortical layer (p50), increased to 76% in distal 50% cortical layer (d50), and peaked at 90% in the distal 20% cortical layer (d20). For those without peritubulitis (PTC 0), the increase in the the Interstitial Fibrosis/Tubular Atrophy (IF/TA) score was accompanied by a significantly increased cortical perfusion. A Polyomavirus infection was associated with an increased cortical perfusion. CONCLUSIONS: Our study demonstrated that the perfusion of the renal transplant is associated with certain pathological changes within the graft. DTPM showed a significant reduction of cortical perfusion in the transplant renal cortex related to peritubular capillary inflammation
[4-(1-Benzofuran-2-yl)phenyl]diphenylamine
The asymmetric unit of the title compound, C26H19NO, contains two molecules. The dihedral angles between the benzofuran and benzene rings are 5.09 (8), 59.02 (8) and 67.74 (8)° in one molecule and 18.70 (8), 52.78 (8) and 41.74 (8)° in the other. Weak intermolecular C—H⋯π interactions help to stabilize the molecular structure
Ultrasonography-guided Percutaneous Interventional Procedures of the Spleen
Since the introduction of real-time ultrasonography (US) to the medicine in late 1970s, the unique benefit of the real-time cross-sectional imaging has made US one of the most widely used imaging modalities to guide interventional procedures. Among the intra-abdominal solid organs, the spleen is the least common solid organ considered for interventional procedures. Although splenic puncture for splenoportography was performed as early as the 1950s and has had a low complication rate, traditionally a direct splenic puncture is still avoided due to the risk of hemorrhage or laceration. US-guided percutaneous drainage of splenic abscesses has been used as a safe alternative procedure for more than 20 years, however, only a few series reporting such an interventional procedure have been published. This review describes briefly the usefulness, technique, safety, and the outcome of US-guided interventional procedures of the spleen
Lexical Retrieval Hypothesis in Multimodal Context
Multimodal corpora have become an essential language resource for language
science and grounded natural language processing (NLP) systems due to the
growing need to understand and interpret human communication across various
channels. In this paper, we first present our efforts in building the first
Multimodal Corpus for Languages in Taiwan (MultiMoco). Based on the corpus, we
conduct a case study investigating the Lexical Retrieval Hypothesis (LRH),
specifically examining whether the hand gestures co-occurring with speech
constants facilitate lexical retrieval or serve other discourse functions. With
detailed annotations on eight parliamentary interpellations in Taiwan Mandarin,
we explore the co-occurrence between speech constants and non-verbal features
(i.e., head movement, face movement, hand gesture, and function of hand
gesture). Our findings suggest that while hand gestures do serve as
facilitators for lexical retrieval in some cases, they also serve the purpose
of information emphasis. This study highlights the potential of the MultiMoco
Corpus to provide an important resource for in-depth analysis and further
research in multimodal communication studies
Exploring Affordance and Situated Meaning in Image Captions: A Multimodal Analysis
This paper explores the grounding issue regarding multimodal semantic
representation from a computational cognitive-linguistic view. We annotate
images from the Flickr30k dataset with five perceptual properties: Affordance,
Perceptual Salience, Object Number, Gaze Cueing, and Ecological Niche
Association (ENA), and examine their association with textual elements in the
image captions. Our findings reveal that images with Gibsonian affordance show
a higher frequency of captions containing 'holding-verbs' and 'container-nouns'
compared to images displaying telic affordance. Perceptual Salience, Object
Number, and ENA are also associated with the choice of linguistic expressions.
Our study demonstrates that comprehensive understanding of objects or events
requires cognitive attention, semantic nuances in language, and integration
across multiple modalities. We highlight the vital importance of situated
meaning and affordance grounding in natural language understanding, with the
potential to advance human-like interpretation in various scenarios.Comment: 10 pages, 9 figure
Soft-tissue Tumor Differentiation Using 3D Power Doppler Ultrasonography With Echo-contrast Medium Injection
BackgroundWe aimed to evaluate the ability of 3-dimensional power Doppler ultrasonography to differentiate soft-tissue masses from blood flow and vascularization with contrast medium.MethodsTwenty-five patients (mean age, 44.1 years; range, 12-77 years) with a palpable mass were enrolled in this study. Volume data were acquired using linear and convex 3-dimensional probes and contrast medium injected manually by bolus. Data were stored and traced slice by slice for 12 slices. All patients were scanned by the same senior sonologist. The vascular index (VI), flow index (FI), and vascular-flow index (VFI) were automatically calculated after the tumor was completely traced. All tumors were later confirmed by pathology.ResultsThe study included 8 benign (mean, 36.5 mL; range, 2.4-124 mL) and 17 malignant (mean, 319.4 mL; range, 9.9-1,179.6 mL) tumors. Before contrast medium injection, mean VI, FI and VFI were, respectively, 3.22, 32.26 and 1.07 in benign tumors, and 1.97, 29.33 and 0.67 in malignant tumors. After contrast medium injection, they were, respectively, 20.85, 37.33 and 8.52 in benign tumors, and 40.12, 41.21 and 17.77 in malignant tumors. The mean differences between with and without contrast injection for VI, FI and VFI were, respectively, 17.63, 5.07 and 7.45 in benign tumors, and 38.15, 11.88 and 16.55 in malignant tumors. Tumor volume, VI, FI and VFI were not significantly different between benign and malignant tumors before and after echo-contrast medium injection. However, VI, FI and VFI under self-differentiation (differences between with and without contrast injection) were significantly different between malignant and benign tumors.ConclusionThree-dimensional power Doppler ultrasound is a valuable tool for differential diagnosis of soft-tissue tumors, especially with the injection of an echo-contrast medium
Trisomy Correction in Down Syndrome Induced Pluripotent Stem Cells
SummaryHuman trisomies can alter cellular phenotypes and produce congenital abnormalities such as Down syndrome (DS). Here we have generated induced pluripotent stem cells (iPSCs) from DS fibroblasts and introduced a TKNEO transgene into one copy of chromosome 21 by gene targeting. When selecting against TKNEO, spontaneous chromosome loss was the most common cause for survival, with a frequency of ∼10−4, while point mutations, epigenetic silencing, and TKNEO deletions occurred at lower frequencies in this unbiased comparison of inactivating mutations. Mitotic recombination events resulting in extended loss of heterozygosity were not observed in DS iPSCs. The derived, disomic cells proliferated faster and produced more endothelia in vivo than their otherwise isogenic trisomic counterparts, but in vitro hematopoietic differentiation was not consistently altered. Our study describes a targeted removal of a human trisomy, which could prove useful in both clinical and research applications
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