Early Recognition of Human Activities from First-Person Videos Using Onset Representations

In this paper, we propose a methodology for early recognition of human activities from videos taken with a first-person viewpoint. Early recognition, which is also known as activity prediction, is an ability to infer an ongoing activity at its early stage. We present an algorithm to perform recognition of activities targeted at the camera from streaming videos, making the system to predict intended activities of the interacting person and avoid harmful events before they actually happen. We introduce the novel concept of 'onset' that efficiently summarizes pre-activity observations, and design an approach to consider event history in addition to ongoing video observation for early first-person recognition of activities. We propose to represent onset using cascade histograms of time series gradients, and we describe a novel algorithmic setup to take advantage of onset for early recognition of activities. The experimental results clearly illustrate that the proposed concept of onset enables better/earlier recognition of human activities from first-person videos

Step size of the rotary proton motor in single FoF1-ATP synthase from a thermoalkaliphilic bacterium by DCO-ALEX FRET

Thermophilic enzymes can operate at higher temperatures but show reduced activities at room temperature. They are in general more stable during preparation and, accordingly, are considered to be more rigid in structure. Crystallization is often easier compared to proteins from bacteria growing at ambient temperatures, especially for membrane proteins. The ATP-producing enzyme FoF1-ATP synthase from thermoalkaliphilic Caldalkalibacillus thermarum strain TA2.A1 is driven by a Fo motor consisting of a ring of 13 c-subunits. We applied a single-molecule F\"orster resonance energy transfer (FRET) approach using duty cycle-optimized alternating laser excitation (DCO-ALEX) to monitor the expected 13-stepped rotary Fo motor at work. New FRET transition histograms were developed to identify the smaller step sizes compared to the 10-stepped Fo motor of the Escherichia coli enzyme. Dwell time analysis revealed the temperature and the LDAO dependence of the Fo motor activity on the single molecule level. Back-and-forth stepping of the Fo motor occurs fast indicating a high flexibility in the membrane part of this thermophilic enzyme.Comment: 14 pages, 7 figure

A new type of Na+-driven ATP synthase membrane rotor with a two-carboxylate ion-coupling motif

Abstract: The anaerobic bacterium Fusobacterium nucleatum uses glutamate decarboxylation to generate a transmembrane gradient of Na+. Here, we demonstrate that this ion-motive force is directly coupled to ATP synthesis, via an F1Fo-ATP synthase with a novel Na+ recognition motif, shared by other human pathogens. Molecular modeling and free-energy simulations of the rotary element of the enzyme, the c-ring, indicate Na+ specificity in physiological settings. Consistently, activity measurements showed Na+ stimulation of the enzyme, either membrane-embedded or isolated, and ATP synthesis was sensitive to the Na+ ionophore monensin. Furthermore, Na+ has a protective effect against inhibitors targeting the ion-binding sites, both in the complete ATP synthase and the isolated c-ring. Definitive evidence of Na+ coupling is provided by two identical crystal structures of the c11 ring, solved by X-ray crystallography at 2.2 and 2.6 Å resolution, at pH 5.3 and 8.7, respectively. Na+ ions occupy all binding sites, each coordinated by four amino acids and a water molecule. Intriguingly, two carboxylates instead of one mediate ion binding. Simulations and experiments demonstrate that this motif implies that a proton is concurrently bound to all sites, although Na+ alone drives the rotary mechanism. The structure thus reveals a new mode of ion coupling in ATP synthases and provides a basis for drug-design efforts against this opportunistic pathogen. Author Summary: Essential cellular processes such as biosynthesis, transport, and motility are sustained by the energy released in the hydrolysis of ATP, the universal energy carrier in living cells. Most ATP in the cell is produced by a membrane-bound enzyme, the ATP synthase, through a rotary mechanism that is coupled to the translocation of ions across the membrane. The majority of ATP synthases are energized by transmembrane electrochemical gradients of protons (proton-motive force), but a number of organisms, including some important human pathogens, use gradients of sodium ions instead (sodium-motive force). The ion specificity of ATP synthases is determined by a membrane-embedded sub-complex, the c-ring, which is the smallest known biological rotor. The functional mechanism of the rotor ring and its variations among different organisms are of wide interest, because of this enzyme's impact on metabolism and disease, and because of its potential for nanotechnology applications. Here, we characterize a previously unrecognized type of Na+-driven ATP synthase from the opportunistic human pathogen Fusobacterium nucleatum, which is implicated in periodontal diseases. We analyzed this ATP synthase and its rotor ring through a multi-disciplinary approach, combining cell-growth and biochemical assays, X-ray crystallography and computer-simulation methods. Two crystal structures of the membrane rotor were solved, at low and high pH, revealing an atypical ion-recognition motif mediated by two carboxylate side-chains. This motif is shared by other human pathogens, such as Mycobacterium tuberculosis or Streptococcus pneumonia, whose ATP synthases are targets of novel antibiotic drugs. The implications of this ion-recognition mode on the mechanism of the ATP synthase and the cellular bioenergetics of F. nucleatum were thus examined. Our results provide the basis for future pharmacological efforts against this important pathogen

Maßnahmen und Determinanten der Kundenbindung deutscher Handelsmarkenhersteller

Die vorliegende Arbeit befasst sich mit der Beziehung zwischen deutschen Handelsmarkenherstellern und den Einzelhandelsunternehmen. Handelsmarken werden in Deutschland noch größtenteils im Preiswettbewerb eingesetzt. Es ist davon auszugehen, dass der Einkauf solcher Handelsmarken seitens des Handels einer starken Preiselastizität unterliegt. Kann der Handel bei einem anderen Hersteller günstiger einkaufen, so vergrößert sich bei gleichbleibendem Endverkaufspreis die Marge des Handels. Da der Hersteller einer Handelsmarke in den seltensten Fällen dem Endkonsumenten bekannt ist, wäre bei grober Betrachtung eine leichte Austauschbarkeit des Herstellers denkbar. Enthält eine Handelsmarke keine tierischen Bestandteile, ist eine Identifikation des Herstellers anhand der Verpackung nahezu unmöglich. Der Konsument würde einen Wechsel des Herstellers bei gleichbleibender Produktqualität nicht bemerken. Die Möglichkeit des für den Konsumenten unbemerkten Auswechselns durch einen anderen Lieferanten bedeutet für die deutschen Handelsmarkenhersteller - die oft für wenige Handelsunternehmen große Mengen produzieren - ein existenzielles Risiko. Dieses Risiko könnte der Handelsmarkenhersteller vermindern, wenn er das Handelsunternehmen als Kunden an sich bindet. Auch in gesamtwirtschaftlicher Betrachtung ist die Thematik relevant. Wenn keine Kundenbindung zwischen Handelsmarkenhersteller und Handel möglich wäre und ausschließlich monetäre Aspekte zählten, wäre langfristig mit einer Verlagerung des Handelsmarkeneinkaufs in das Ausland zu rechnen, da dort überwiegend günstiger produziert werden kann. Für deutsche Hersteller stellt der internationale Wettbewerb teilweise eine deutliche Bedrohung dar. Wenn der Handel größtenteils auf ausländische Handelsmarkenproduzenten zurückgreifen würde, ergäben sich direkte Auswirkungen auf die gesamtwirtschaftliche Situation Deutschlands bezüglich Wachstum, Arbeitsmarkt etc. Die sich darstellende Problematik betrifft nicht ausschließlich den einzelnen Handelsmarkenhersteller. Premium-, Zweit- und Drittmarkenhersteller betrifft dies ebenso wie Konsumenten und die gesamte Volkswirtschaft. Die Faktoren, die eine bestehende Handelsmarkenhersteller-Handelsbeziehung beeinflussen, sind vielfältig. Neben den externen Faktoren des individuellen Umfelds existieren Faktoren der direkten Verbindung zwischen beiden Partnern: Wenn Kundenbindung möglich ist, welche Faktoren sind als Bindungsparameter geeignet? Zählen ausschließlich Faktoren wie der Preis? Wie relevant ist die Produktqualität oder realisierbare Liefermengen? Wie wichtig sind Servicepolitik oder Kommunikationsmaßnahmen des Herstellers? Welche Bedeutung hat die Größe und das Image eines Herstellers? Ergeben sich Unterschiede, wenn ein bekannter Markenhersteller die Handelsmarke produziert oder ein reiner Handelsmarkenhersteller? Wie sieht die Beziehung zwischen Handelsmarkenhersteller und Handel generell aus? Welche Rolle spielen technische und organisatorische Besonderheiten der jeweiligen Branche? Lassen sich aufgrund dieser Faktoren Markteintrittsbarrieren für ausländische Mitbewerber errichten? Diese Fragen sollen im Folgenden betrachtet und analysiert werden

Terrain-Adaptive Navigation Architecture

A navigation system designed for a Mars rover has been designed to deal with rough terrain and/or potential slip when evaluating and executing paths. The system also can be used for any off-road, autonomous vehicles. The system enables vehicles to autonomously navigate different terrain challenges including dry river channel systems, putative shorelines, and gullies emanating from canyon walls. Several of the technologies within this innovation increase the navigation system s capabilities compared to earlier rover navigation algorithms

Feeding live prey to zoo animals: response of zoo visitors in Switzerland

In summer 2007, with the help of a written questionnaire, the attitudes of more than 400 visitors to the zoological garden of Zurich, Switzerland, toward the idea of feeding live insects to lizards, live fish to otters, and live rabbits to tigers were investigated. The majority of Swiss zoo visitors agreed with the idea of feeding live prey (invertebrates and vertebrates) to zoo animals, both off- and on-exhibit, except in the case of feeding live rabbits to tigers on-exhibit. Women and frequent visitors of the zoo disagreed more often with the on-exhibit feeding of live rabbits to tigers. Study participants with a higher level of education were more likely to agree with the idea of feeding live invertebrates and vertebrates to zoo animals off-exhibit. In comparison to an earlier study undertaken in Scotland, zoo visitors in Switzerland were more often in favor of the live feeding of vertebrates. Feeding live prey can counter the loss of hunting skills of carnivores and improve the animals’ well-being. However, feeding enrichments have to strike a balance between optimal living conditions of animals and the quality of visitor experience. Our results show that such a balance can be found, especially when live feeding of mammals is carried out off-exhibit. A good interpretation of food enrichment might help zoos to win more support for the issue, and for re-introduction programs and conservation

Automated glycan assembly of a S. pneumoniae serotype 3 CPS antigen

Vaccines against S. pneumoniae, one of the most prevalent bacterial infections causing severe disease, rely on isolated capsular polysaccharide (CPS) that are conjugated to proteins. Such isolates contain a heterogeneous oligosaccharide mixture of different chain lengths and frame shifts. Access to defined synthetic S. pneumoniae CPS structures is desirable. Known syntheses of S. pneumoniae serotype 3 CPS rely on a time-consuming and low-yielding late-stage oxidation step, or use disaccharide building blocks which limits variability. Herein, we report the first iterative automated glycan assembly (AGA) of a conjugation-ready S. pneumoniae serotype 3 CPS trisaccharide. This oligosaccharide was assembled using a novel glucuronic acid building block to circumvent the need for a late-stage oxidation. The introduction of a washing step with the activator prior to each glycosylation cycle greatly increased the yields by neutralizing any residual base from deprotection steps in the synthetic cycle. This process improvement is applicable to AGA of many other oligosaccharides

ii Control of chaotic population dynamics

Ecological and economic consideration

First-Person Activity Recognition: What Are They Doing to Me?

This paper discusses the problem of recognizing interaction-level human activities from a first-person view-point. The goal is to enable an observer (e.g., a robot or a wearable camera) to understand ‘what activity others are performing to it ’ from continuous video inputs. These include friendly interactions such as ‘a person hugging the observer ’ as well as hostile interactions like ‘punching the observer ’ or ‘throwing objects to the observer’, whose videos involve a large amount of camera ego-motion caused by physical interactions. The paper investigates multi-channel kernels to integrate global and local motion in-formation, and presents a new activity learning/recognition methodology that explicitly considers temporal structures displayed in first-person activity videos. In our experi-ments, we not only show classification results with seg-mented videos, but also confirm that our new approach is able to detect activities from continuous videos reliably. 1