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关键词： Object detection   Feature extraction   Satellites   Neural networks   Automobiles   Sensors   Deep learning   Deep learning   faster R-CNN   neural networks   object classification   satellite images   vehicle detection   YOLO   Darknet  

摘要： Object detection and classification is important for video surveillance applications. Counting vehicles like cars, truck and vans is useful for intelligent transportation systems to identify dense and sparse roads, track loaded vehicles at the country borders. Even though many solutions such as appearance-based (Multi-block Local Binary Pattern) and model-based ((DATMO) algorithm) are proposed to classify the moving objects within the satellite images using machine learning and deep learning techniques, they either have over fitting problems or low performance. Hence these challenges have to be addressed during detecting and classifying the objects. Instead of training the classifiers with hand-crafted features, this paper uses neural network based object detection and classification to achieve promising accuracy better than the humans. Invariant feature concept is added to the existing Darknet Architecture of You Only Look Once (YOLO) and is combined with Faster Region-Based Convolutional Neural Networks (Faster R-CNN) to count the number of vehicles with different spatial locations. This combined model improves feature extraction step and vehicle classification process. The proposed system is tested on two benchmark datasets Cars Overhead with Context (COWC) and Vehicle Detection in Aerial Imagery (VEDAI) for counting the cars and trucks. Experimental results prove that the proposed system is better by 9% in detecting smaller objects than existing works.

关键词： chemogenomic profiling   marine natural products   mechanism of action   membrane interactions  

摘要： Amantelide A, a polyhydroxylated macrolide isolated from a marine cyanobacterium, displays broad-spectrum activity against mammalian cells, bacterial pathogens, and marine fungi. We conducted comprehensive mechanistic studies to identify the molecular targets and pathways affected by amantelide A. Our investigations relied on chemical structure similarities with compounds of known mechanisms, yeast knockout mutants, yeast chemogenomic profiling, and direct biochemical and biophysical methods. We established that amantelide A exerts its antifungal action by binding to ergosterol-containing membranes followed by pore formation and cell death, a mechanism partially shared with polyene antifungals. Binding assays demonstrated that amantelide A also binds to membranes containing epicholesterol or mammalian cholesterol, thus suggesting that the cytotoxicity to mammalian cells might be due to its affinity to cholesterol-containing membranes. However, membrane interactions were not completely dependent on sterols. Yeast chemogenomic profiling suggested additional direct or indirect effects on actin. Accordingly, we performed actin polymerization assays, which suggested that amantelide A also promotes actin polymerization in cell-free systems. However, the C-33 acetoxy derivative amantelide B showed a similar effect on actin dynamics in vitro but no significant activity against yeast. Overall, these studies suggest that the membrane effects are the most functionally relevant for amantelide A mechanism of action.

关键词： Diseases  

摘要： Circulating tumor DNA (ctDNA)-based mutation detection is promising to change the clinical practice of genotype-directed therapy for cancer. A growing number of non-invasive tests for cancer screening and monitoring that involve the detection of ctDNA have been commercialized. Primary reference measurement procedures (PRMPs) and reference materials (RMs) are urgently needed to assess the non-invasive tests. In this study, a PRMP based on digital PCR (dPCR) and ctDNA RMs for quantification of the frequently occurring variant in epidermal growth factor receptor (EGFR L858R, T790M, and 19Del) in non-small cell lung cancer (NSCLC) were established. The candidate dPCR PRMP showed high specificity (false positive rate 0-0.003%), good repeatability (coefficient of variance (CV), 2-3% for 10(4) copies/reaction), and high interlaboratory reproducibility (3-10%). A good linearity (0.97 < slope < 1.03, R-2 >= 0.9999) between the measured mutant (MU) value and prepared value was observed for all assays over the fractional abundance (FA) range, between 25% and 0.05%. The limit of quantification (LoQ) was determined to be 34 L858R, 23 T790M, and 34 19Del copies/reaction, corresponding to a FA of 0.2%. An inter-laboratory study of using the EGFR ctDNA RMs and dPCR assays demonstrated that the participating laboratories produced consistent concentrations of MU and wild-type (WT), as well as FA. This study demonstrates that dPCR can act as a potential PRMP for EGFR mutation for validation of NSCLC genotyping tests and ctDNA quantitative tests. The PRMP and RMs established here could improve interlaboratory repeatability and reproducibility, which supports rapid translation and application of non-invasive tests into clinical practice.

关键词： aggressive behavior   CD30+primary cutaneous anaplastic large cell lymphoma   clinical manifestation   pathology   radiotherapy  

摘要： Introduction: CD30+ primary cutaneous anaplastic large cell lymphoma (PC-ALCL) is a rare T-cell neoplasm, and has been reported to present with an indolent behavior. The PC-ALCL with aggressive behavior has not been reported in the literature. Patient concerns: We treated a patient with PC-ALCL that exhibited indolent behavior in the past 2 years and aggressive behavior within the last 3 months before presentation. Diagnosis: Aggressive CD30+ primary cutaneous anaplastic large cell lymphoma. Interventions: The radiotherapy regimen was individualized in terms of the target volume delineation and dose prescription, and the dose-response relationship was evaluated. Outcomes: The mean distance of microscopic infiltration was 14.1 mm in depth and 14.3 mm circumferentially. The lesion completely regressed after the delivery of 40 Gy in 20 fractions over 4 weeks. The tumor did not recur over the next year. Conclusion: An aggressive disease course is rare for indolent CD30+ PC-ALCL, which has similar histopathological characteristics as indolent PC-ALCL. The radiotherapy strategy should be individualized with curative intent.