Query-Focused Video Summarization: Dataset, Evaluation, and A Memory Network Based Approach

Recent years have witnessed a resurgence of interest in video summarization. However, one of the main obstacles to the research on video summarization is the user subjectivity - users have various preferences over the summaries. The subjectiveness causes at least two problems. First, no single video summarizer fits all users unless it interacts with and adapts to the individual users. Second, it is very challenging to evaluate the performance of a video summarizer. To tackle the first problem, we explore the recently proposed query-focused video summarization which introduces user preferences in the form of text queries about the video into the summarization process. We propose a memory network parameterized sequential determinantal point process in order to attend the user query onto different video frames and shots. To address the second challenge, we contend that a good evaluation metric for video summarization should focus on the semantic information that humans can perceive rather than the visual features or temporal overlaps. To this end, we collect dense per-video-shot concept annotations, compile a new dataset, and suggest an efficient evaluation method defined upon the concept annotations. We conduct extensive experiments contrasting our video summarizer to existing ones and present detailed analyses about the dataset and the new evaluation method

Fully-Coupled Two-Stream Spatiotemporal Networks for Extremely Low Resolution Action Recognition

A major emerging challenge is how to protect people's privacy as cameras and computer vision are increasingly integrated into our daily lives, including in smart devices inside homes. A potential solution is to capture and record just the minimum amount of information needed to perform a task of interest. In this paper, we propose a fully-coupled two-stream spatiotemporal architecture for reliable human action recognition on extremely low resolution (e.g., 12x16 pixel) videos. We provide an efficient method to extract spatial and temporal features and to aggregate them into a robust feature representation for an entire action video sequence. We also consider how to incorporate high resolution videos during training in order to build better low resolution action recognition models. We evaluate on two publicly-available datasets, showing significant improvements over the state-of-the-art.Comment: 9 pagers, 5 figures, published in WACV 201

The structural and functional integrity of peripheral nerves depends on the glial-derived signal desert hedgehog

We show that desert hedgehog ( dhh), a signaling molecule expressed by Schwann cells, is essential for the structural and functional integrity of the peripheral nerve. Dhh-null nerves display multiple abnormalities that affect myelinating and nonmyelinating Schwann cells, axons, and vasculature and immune cells. Myelinated fibers of these mice have a significantly increased ( more than two times) number of Schmidt-Lanterman incisures ( SLIs), and connexin 29, a molecular component of SLIs, is strongly upregulated. Crossing dhh-null mice with myelin basic protein ( MBP)-deficient shiverer mice, which also have increased SLI numbers, results in further increased SLIs, suggesting that Dhh and MBP control SLIs by different mechanisms. Unmyelinated fibers are also affected, containing many fewer axons per Schwann cell in transverse profiles, whereas the total number of unmyelinated axons is reduced by approximately one-third. In dhh-null mice, the blood-nerve barrier is permeable and neutrophils and macrophage numbers are elevated, even in uninjured nerves. Dhh-null nerves also lack the largest-diameter myelinated fibers, have elevated numbers of degenerating myelinated axons, and contain regenerating fibers. Transected dhh nerves degenerate faster than wild-type controls. This demonstrates that a single identified glial signal, Dhh, plays a critical role in controlling the integrity of peripheral nervous tissue, in line with its critical role in nerve sheath development ( Parmantier et al., 1999). The complexity of the defects raises a number of important questions about the Dhh-dependent cell-cell signaling network in peripheral nerves

Optimization of DNA extraction and amplified fragment length polymorphism (AFLP) analysis of pomegranate (Punica granatum L.)

Pomegranate (Punica granatum L.) is a plant rich in polysaccharides, polyphenols and secondary metabolites, which makes it difficult to obtain high quality DNA. The present study reports a quick, simple and inexpensive method to isolate genomic DNA suitable for amplified fragment length polymorphism (AFLP) analysis and other PCR-based applications. This method is a modification of a protocol described by Doyle and Doyle (1990). It is a cetyl trimethyl ammonium bromide (CTAB)-based protocol modified by the use of potassium acetate (KoAc) and  polyvinylpyrrolidone (PVP) to remove polyphenols and polysaccharides and a high concentration of β-mercaptoethanol to reduce oxidation. Moreover, the final optimized protocol was then compared with three different methods, which are routinely used for many plant species. The results show that our modified CTAB protocol produced a high yield (>500 ng/μl) of good-quality DNA (A<sub>260</sub>/A<sub>280</sub> >1.8) compared to the other three methods. The DNA purity was further confirmed by complete digestion with EcoRI and MseI enzymes. The modified CTAB protocol used in this study could be a useful protocol for extraction of high quality DNA not only for pomegranate but also for other plants rich in polysaccharides, polyphenolices and secondary metabolites. Using this method, DNA was extracted from 67 accessions of pomegranate. The DNA was then used for AFLP analysis. To optimize the AFLP protocol, the effects of MgCl2 concentration during selective amplification, the dilution level of pre-amplified DNA and the cycle number used in the preamplification were studied. After optimization of the reaction conditions, AFLP was used to study genetic diversity among Iranian pomegranate accessions.Keywords: Pomegranate, DNA extraction, amplified fragment length polymorphism (AFLP), secondary metabolites.African Journal of Biotechnology Vol. 12(34), pp. 5252-525

Vergleichende Analyse des Einflusses von Hyperoxie und physischer Belastung auf die Expression von inflammatorischen und anti-oxidativen Faktoren in peripheren mononukleären Blutzellen

Taucher sowie Patienten während einer hyperbaren Oxygenierung (HBO) und HBO-Therapie oder auch in der Anästhesiologie sind erhöhten Sauerstoffpartialdrücken ausgesetzt. Dadurch können erhöhte Mengen von freien Sauerstoff- und Stickstoffradikalen freigesetzt werden, die zu Zellschädigungen führen können. Ebenso können unter physischer Belastung, wie z.B. bei Leistungssportlern oder Athleten, freie Radikale entstehen. Ziel dieser Studie war es daher vergleichend zu untersuchen, ob und wie sich die Exposition von HBO auf die Expression von pro- und anti-inflammatorischen Zytokinen sowie anti-oxidativen Faktoren in peripheren mononukleären Blutzellen (PBMCs) von Athleten und Kampfschwimmern im Vergleich zu körperlich weniger aktiven Kontrollpersonen auswirkt. Dafür wurden zunächst die PBMCs aus allen drei Probandengruppen direkt nach der Isolierung bezüglich ihrer Expressionslevel der oben genannten Faktoren untersucht (basale Expression). Weiterhin wurden die PBMCs in einer Druckkammer für vier Stunden 4 bar Sauerstoffpartialdruck oder in einer Kontrollkammer Umgebungsbedingungen ausgesetzt, um den Einfluss von HBO auf die PBMCs der drei Gruppen zu untersuchen. Die Expression der inflammatorischen und anti-oxidativen Faktoren wurde zudem noch nach einer Erholungszeit von 18 Stunden untersucht, um zu überprüfen, ob und wie schnell sich die PBMCs von der Exposition gegenüber erhöhten Sauerstoffpartialdrücken erholen. Die Ergebnisse der Realtime-PCR-Analyse zeigen, dass es bereits basal signifikante Unterschiede bzgl. der Expressionslevel innerhalb der drei Gruppen gab. So war die basale Expression von NQO1, IL-6, IL-12, IFN-γ und IL-10 bei den Kampfschwimmern am höchsten, während Athleten die höchste basale Expression von HO-1 und die Kontrollprobanden die höchste Expression von TGF-β1 und IL-1β in den PBMCs aufwiesen. Nach vier stündiger Exposition gegenüber HBO kam es zu einer starken Aufregulation der pro-inflammatorischen Zytokine IL-6 und IL-1β in den PBMCs der Kampfschwimmer. Die Expression von IFN-γ war nach HBO hingegen in PBMCs von Kontrollpersonen am höchsten. Die stärkste Expressionsänderung nach HBO zeigten die Athleten bei dem anti-oxidativen Faktor NQO1. Allerdings hatte HBO keinen besonderen Einfluss auf die Expression der entzündungshemmenden Zytokine gezeigt. Nach der 18 stündigen Erholungsphase konnte in den PBMCs aller drei Gruppen eine verminderte Expression der pro-inflammatorischen Zytokine sowie des anti-oxidativen Faktors NQO1 beobachtet werden. Im Gegensatz dazu kam es zu einer Aufregulation von HO-1, die am stärksten in den PBMCs der Kampfschwimmer war. Ebenso kam es in den PBMCs dieser Gruppe zu einer Aufregulation der entzündungshemmenden Zytokine TGF-β1 und IL-10. Diese Ergebnisse dieser Arbeit weisen darauf hin, dass eine Exposition gegenüber HBO in Kombination mit körperlicher Aktivität eher zu einem pro-inflammatorischen Status der PBMCs in den Kampfschwimmern führt als körperliche Aktivität (in den Athleten) allein. Im Rahmen einer Erholungsphase kann es jedoch über eine Erhöhung von anti-inflammatorischen Zytokine zu einer Dämpfung dieses pro-inflammatorischen Status kommen