Multiscale Change-Point Inference

We introduce a new estimator SMUCE (simultaneous multiscale change-point estimator) for the change-point problem in exponential family regression. An unknown step function is estimated by minimizing the number of change-points over the acceptance region of a multiscale test at a level \alpha. The probability of overestimating the true number of change-points K is controlled by the asymptotic null distribution of the multiscale test statistic. Further, we derive exponential bounds for the probability of underestimating K. By balancing these quantities, \alpha will be chosen such that the probability of correctly estimating K is maximized. All results are even non-asymptotic for the normal case. Based on the aforementioned bounds, we construct asymptotically honest confidence sets for the unknown step function and its change-points. At the same time, we obtain exponential bounds for estimating the change-point locations which for example yield the minimax rate O(1/n) up to a log term. Finally, SMUCE asymptotically achieves the optimal detection rate of vanishing signals. We illustrate how dynamic programming techniques can be employed for efficient computation of estimators and confidence regions. The performance of the proposed multiscale approach is illustrated by simulations and in two cutting-edge applications from genetic engineering and photoemission spectroscopy

Heterogeneous Change Point Inference

We propose HSMUCE (heterogeneous simultaneous multiscale change-point estimator) for the detection of multiple change-points of the signal in a heterogeneous gaussian regression model. A piecewise constant function is estimated by minimizing the number of change-points over the acceptance region of a multiscale test which locally adapts to changes in the variance. The multiscale test is a combination of local likelihood ratio tests which are properly calibrated by scale dependent critical values in order to keep a global nominal level alpha, even for finite samples. We show that HSMUCE controls the error of over- and underestimation of the number of change-points. To this end, new deviation bounds for F-type statistics are derived. Moreover, we obtain confidence sets for the whole signal. All results are non-asymptotic and uniform over a large class of heterogeneous change-point models. HSMUCE is fast to compute, achieves the optimal detection rate and estimates the number of change-points at almost optimal accuracy for vanishing signals, while still being robust. We compare HSMUCE with several state of the art methods in simulations and analyse current recordings of a transmembrane protein in the bacterial outer membrane with pronounced heterogeneity for its states. An R-package is available online

Estimating Economic Benefits of Allowing a Flexible Window for Maryland Purchases of Sponge Crabs

We estimate that crabmeat industry revenues from processing sponge crabs can increase by at least 56% over the current estimated value of production, from $1.6 million to$2.5 million. This gain can be realized by moving from the current fixed opening of the season during which the Maryland industry can purchase sponge crabs to a flexible starting date to the season that lasts the same number of days as the current system. This change would have the added advantage of reducing the variability in revenues that come from processing sponge crabs. Our modeling of the decision to open the season is based on a minimum amount of information. It is expected that with more sophisticated analysis of the market situation during the season, experts can optimize the opening date and increase the revenues even further.Resource /Energy Economics and Policy,

Improved N transfer by growing catch crops – a challenge

Diese Literaturübersicht in Kombination mit unveröffentlichten Daten zeigt verschiedene Verlustursachen von Stickstoff (N) aus ackerbaulich genutzten Böden auf und diskutiert, inwieweit der Anbau von Zwischenfrüchten helfen kann, N-Verluste aus dem System Boden-Pflanze zu vermindern. Der Pool an Nitratstickstoff im Boden im Herbst kann als Ausgangspunkt für verschiedene Verlustpfade von N (gasförmige Verluste, Auswaschung) aus dem System Boden-Pflanze angesehen werden. Eine Verkleinerung des Bodennitratpools verringert die Verlust­risiken und die damit verbundene Belastung der Umwelt. Der Input zum Nitratpool kann durch eine optimierte N-Düngung der Vorfrucht und eine damit einhergehende Reduzierung der N-Überschüsse vermindert werden. Zudem kann eine reduzierte Bodenbearbeitung einer verstärkten N-Freisetzung nach der Ernte der Vorfrucht entgegenwirken. Zwischenfrüchte und teilweise auch Hauptfrüchte können bereits vor Winter erhebliche N-Mengen in ihrer Biomasse akkumulieren und somit vor einer Verlagerung in tiefere Bodenschichten bewahren. Voraussetzung für eine nachhaltige Verbesserung der N-Ausnutzung ist jedoch, dass der aus den Residuen der Zwischenfrucht freiwerdende Stickstoff von der/den nachfolgenden Hauptfrucht/-früchten für ihre Ertragsbildung genutzt wird; andernfalls wird das Problem nur um ein Jahr verschoben. Da Umfang und Zeitpunkt der N-Mineralisation unter anderem von der N-Menge im Zwischenfruchtbestand, dem C:N-Verhältnis der Residuen, Einarbeitungstermin der Residuen und der nachfolgenden Witterung abhängt, ist eine präzise Voraussage des N-Transfers in die Folgefrucht schwierig. Darüber hinaus muss bei der Wahl der geeigneten Zwischenfrucht (-mischungen) darauf geachtet werden, dass keine Schad­erreger vermehrt werden, die auch die Nach­früchte infizieren können.Based on the literature amended by some unpublished data and data compilations from the literature, this review identifies the mechanisms of nitrogen (N) losses from arable land and explores the potential of growing catch crops to mitigate N loss risks from the soil-plant system. The nitrate pool in the soil can be regarded as starting point of most of the N losses via gaseous losses and/or leaching from the soil-plant system. Depleting this pool, especially in autumn, lowers the risk of losses and related impairments of the environment. The input into the nitrate pool can be reduced by adjusting the N fertilization to the N demand of the preceding crop, thus decreasing the N surplus. Less intensive soil tillage after the harvest of the preceding crop may lessen N release from the soil organic matter and the crop residues. On the other hand, cover or catch crops and, to a lesser extent, main crops can take up considerable N amounts in autumn and prevent it from being lost. However, in order to reduce N fertilization of the subsequent crop due to an improved N transfer, the big challenge is to harmonize the N demand of the subsequent main crop and the N release from the catch crop residues. Since the latter depends on several factors like accumulated N amount, C:N ratio of the residues, incorporation date and weather conditions, it can hardly be estimated. Another crucial point is the choice of a suitable cover crop because it should not propagate pests or diseases of the main crops

Immune Response Modulation by Tumor-Secreted Glycosphingolipids

Although originally considered merely structural components of cellular membranes, glycosphingolipids (GSL) arenow recognized as having critical effects on cellular physiology, including proliferation, differentiation, viraltransformation and ontogenesis. In addition, a vast majority of human cancers have modified GSL compositioncompared to parental normal cells. These modifications may contribute to both tumor survival and exert strikingeffects on anti-tumor immunity. In this review, we discuss mechanisms of immune modulation by tumor-secreted GSL.Fil: Lardone, Ricardo Dante. John Wayne Cancer Institute at Providence Saint John’s Health Center. Santa Monica; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Cely, Ingrid. John Wayne Cancer Institute at Providence Saint John’s Health Center. Santa Monica; Estados UnidosFil: Sieling, Peter A.. John Wayne Cancer Institute at Providence Saint John’s Health Center. Santa Monica; Estados UnidosFil: Lee, Delphine. John Wayne Cancer Institute at Providence Saint John’s Health Center. Santa Monica; Estados Unido

Decarbonizing economies through carbon pricing - is there an ideal policy mix? - Development and relevance of a feasible emission mitigation strategy for China

Explicit and implicit carbon pricing are indispensable to reduce emissions and direct economies towards carbon neutrality. This report aimed to investigate whether there is a policy mix that is the most effective in emission reduction. A cluster analysis showed that stringent market-based instruments such as the CO2 tax are substantial for effective emission abatement. In a second step, a political feasibility analysis was conducted to investigate how China can improve their environmental policy framework further. This showed the importance of leveraging both explicit and implicit pricing when setting up successful, national carbon pricing strategies