A Macroecological Analysis of SERA Derived Forest Heights and Implications for Forest Volume Remote Sensing

Individual trees have been shown to exhibit strong relationships between DBH, height and volume. Often such studies are cited as justification for forest volume or standing biomass estimation through remote sensing. With resolution of common satellite remote sensing systems generally too low to resolve individuals, and a need for larger coverage, these systems rely on descriptive heights, which account for tree collections in forests. For remote sensing and allometric applications, this height is not entirely understood in terms of its location. Here, a forest growth model (SERA) analyzes forest canopy height relationships with forest wood volume. Maximum height, mean, H100, and Lorey's height are examined for variability under plant number density, resource and species. Our findings, shown to be allometrically consistent with empirical measurements for forested communities world-wide, are analyzed for implications to forest remote sensing techniques such as LiDAR and RADAR. Traditional forestry measures of maximum height, and to a lesser extent H100 and Lorey's, exhibit little consistent correlation with forest volume across modeled conditions. The implication is that using forest height to infer volume or biomass from remote sensing requires species and community behavioral information to infer accurate estimates using height alone. SERA predicts mean height to provide the most consistent relationship with volume of the height classifications studied and overall across forest variations. This prediction agrees with empirical data collected from conifer and angiosperm forests with plant densities ranging between 102–106 plants/hectare and heights 6–49 m. Height classifications investigated are potentially linked to radar scattering centers with implications for allometry. These findings may be used to advance forest biomass estimation accuracy through remote sensing. Furthermore, Lorey's height with its specific relationship to remote sensing physics is recommended as a more universal indicator of volume when using remote sensing than achieved using either maximum height or H100

The V471A polymorphism in autophagy-related gene ATG7 modifies age at onset specifically in Italian Huntington disease patients

The cause of Huntington disease (HD) is a polyglutamine repeat expansion of more than 36 units in the huntingtin protein, which is inversely correlated with the age at onset of the disease. However, additional genetic factors are believed to modify the course and the age at onset of HD. Recently, we identified the V471A polymorphism in the autophagy-related gene ATG7, a key component of the autophagy pathway that plays an important role in HD pathogenesis, to be associated with the age at onset in a large group of European Huntington disease patients. To confirm this association in a second independent patient cohort, we analysed the ATG7 V471A polymorphism in additional 1,464 European HD patients of the “REGISTRY” cohort from the European Huntington Disease Network (EHDN). In the entire REGISTRY cohort we could not confirm a modifying effect of the ATG7 V471A polymorphism. However, analysing a modifying effect of ATG7 in these REGISTRY patients and in patients of our previous HD cohort according to their ethnic origin, we identified a significant effect of the ATG7 V471A polymorphism on the HD age at onset only in the Italian population (327 patients). In these Italian patients, the polymorphism is associated with a 6-years earlier disease onset and thus seems to have an aggravating effect. We could specify the role of ATG7 as a genetic modifier for HD particularly in the Italian population. This result affirms the modifying influence of the autophagic pathway on the course of HD, but also suggests population-specific modifying mechanisms in HD pathogenesis

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Wie schneiden Sie ab?: Studie über Kontroll- und Prüfungsaktivitäten bei mittelgrossen Unternehmen, Spitälern und Hochschulen in der Schweiz

Kontroll- und Prüfungsaktivitäten unterstützen den Verwaltungsrat und die Geschäftsleitung bei der Steuerung und Kontrolle des Unternehmens. Bei mittelgrossen Unternehmen ist aufgrund der begrenzten personellen und finanziellen Ressourcen ein effektiver und effizienter Einsatz dieser Aktivitäten unerlässlich. Auch bei Spitälern und Hochschulen gewinnen Kontroll- und Prüfungsaktivitäten infolge erhöhter Wettbewerbsintensität und steigenden Kostendrucks sowie zunehmender Unabhängigkeit dieser Organisationen an Bedeutung. Vor diesem Hintergrund haben das Institut für Rechnungswesen und Controlling der Universität Zürich und die PricewaterhouseCoopers AG im Sommer 2008 untersucht, ob und in welchem Ausmass Kontroll- und Prüfungsaktivitäten bei mittelgrossen Unternehmen, Spitälern und Hochschulen vorhanden sind, wie sie ausgestaltet sind und wie die einzelnen Aktivitäten aufeinander abgestimmt werden. Des Weiteren wurden die diesbezüglichen Erwartungen und die gegenwärtigen Herausforderungen der befragten Organisationen eruiert

Digital playing desk: A case study for Augmented Reality

Abstract To compare the advantages and disadvantages of a "Natural User Interface" (se

Dynamic Neural Network-Based Sliding Mode Estimation of Quadrotor Systems

A dynamic neural network (DNN)-based observer design is presented, which amalgamates an adaptive neural network-based technique with a sliding mode estimation method. The proposed observer design is motivated by practical quadrotor tracking control applications, where direct sensor measurements of translational and rotational rates are not available for feedback. While sliding mode estimation strategies are well established as an effective means to compensate for bounded disturbances and dynamic model uncertainty, the proposed observer design employs a feedforward adaptive DNN-based estimation term in addition to a robust, high-gain feedback sliding mode element. The use of the DNN-based term in the estimator design is motivated by the desire to improve transient performance and reduce steady state error. The DNN-based feedforward term could also offer the advantage of reducing the control effort that would be required when the proposed observer design is operating as part of a closed-loop control system. A Lyapuov-based stability analysis is utilized to prove that the proposed DNN-based observer achieves asymptotic estimation of the quadrotor altitude and attitude rates in the presence of model uncertainty and bounded disturbances (e.g., sensor noise). Numerical simulation results are also provided to demonstrate the improved performance that is achieved by incorporating the adaptive DNN in the observer

„Choice and voice“ in Schulen mit personalisierten Lernkonzepten aus Sicht der Schülerinnen und Schüler

Choice and voice ist eine zentrale Forderung im Kontext personalisierter Lernkonzepte und steht für den Anspruch den Schüler*innen Wahl- und Mitbestimmungsmöglichkeiten einzuräumen. Unabhängig der neuen Rhetorik haben verschiedene innovative Schulen langjährige Praxiserfahrung mit Wahl- und Mitbestimmungsmöglichkeiten, wobei wenig über deren Wahrnehmung aus Sicht der Schüler*innen bekannt ist. Der vorliegende Beitrag untersucht, wie Schüler*innen der Sekundarstufe I choice and voice in Schulen mit personalisierten Lernkonzepten wahrnehmen. Die Ergebnisse zeigen, dass die Schüler*innen regelmäßig Wahlfreiheit wahrnehmen, insbesondere was lernorganisatorische Fragen betrifft. Die Möglichkeit, Inhalte und Ziele mitzubestimmen, nehmen sie als weniger ausgeprägt wahr. Der Personalisierungsgrad als Maß dafür, wie stark sich eine Schule aus Sicht der Lehrpersonen an personalisierten Lernkonzepten orientiert, erweist sich in einem Mehrebenen-Strukturgleichungsmodell als relevanter Prädiktor zur Vorhersage der Wahrnehmung der Schüler*innen in Bezug auf Wahl- und Mitbestimmungsmöglichkeiten. Des Weiteren zeigt sich, dass häufiger wahrgenommene Wahl- und Mitbestimmungsmöglichkeiten mit einer stärker positiv wahrgenommenen Unterstützung der Lehrperson einhergehen. Der Artikel leistet einen Beitrag zur Klärung des vielschichtigen Personalisierungsbegriffes, indem er zeigt, dass choice and voice nicht nur aus theoretischer, sondern auch aus empirischer Sicht eine wichtige Dimension personalisierter Lernkonzepte darstellt