Bandwidth selection for kernel density estimation: a review of fully automatic selectors

On the one hand, kernel density estimation has become a common tool for empirical studies in any research area. This goes hand in hand with the fact that this kind of estimator is now provided by many software packages. On the other hand, since about three decades the discussion on bandwidth selection has been going on. Although a good part of the discussion is about nonparametric regression, this parameter choice is by no means less problematic for density estimation. This becomes obvious when reading empirical studies in which practitioners have made use of kernel densities. New contributions typically provide simulations only to show that the own selector outperforms some of the existing methods. We review existing methods and compare them on a set of designs that exhibit few bumps and exponentially falling tails. We concentrate on small and moderate sample sizes because for large ones the differences between consistent methods are often negligible, at least for practitioners. As a byproduct we find that a mixture of simple plug-in and cross-validation methods produces bandwidths with a quite stable performanc

Implementing miscanthus into farming systems:A review of agronomic practices, capital and labour demand

Miscanthus is a promising bioeconomy crop with several biomass utilisation pathways. However, its current cultivation area in Europe is relatively low. This is most likely due to a lack of knowledge about the imple- mentation of miscanthus into farming systems. This study reviews current best practices and suitable land areas for miscanthus cultivation. Biomass production costs and labour requirements were evaluated over the whole 20- year cultivation cycle of four utilisation pathways: combustion, animal bedding, and both conventional and organic biogas production. The assessment was performed for two field sizes (1 and 10 ha), two average annual yield levels (15 and 25 t dry matter ha 1), and both green and brown harvest regimes. The maximum attainable annual gross margins are 1657 € ha 1 for combustion, 13,920 € ha 1 for animal bedding, 2066 € ha 1 for conventional and 2088 € ha 1 for organic biogas production. The combustion pathway has the lowest labour demand (141.5 h ha 1), and animal bedding the highest (317.6 h ha 1) due to additional baling during harvest. Suitable cultivation areas include depleted soils, erosion-prone slopes, heavy clay soils and ecological focus areas such as riparian buffer zones and groundwater protection areas. On such sites, miscanthus would (i) improve soil and water quality, and (ii) enable viable agricultural land utilisation even on scattered patches and strips. Due to its low demands and perennial nature, miscanthus is suitable for sustainable intensification of indus- trial crop cultivation in a growing bioeconomy, benefiting soil and water quality, while providing large amounts of biomass for several utilisation pathways

Effect of a multinutrient intervention after ischemic stroke in female C57Bl/6 mice.

Stroke can affect females very differently from males, and therefore preclinical research on underlying mechanisms and the effects of interventions should not be restricted to male subjects, and treatment strategies for stroke should be tailored to benefit both sexes. Previously, we demonstrated that a multinutrient intervention (Fortasyn) improved impairments after ischemic stroke induction in male C57Bl/6 mice, but the therapeutic potential of this dietary treatment remained to be investigated in females. We now induced a transient middle cerebral artery occlusion (tMCAo) in C57Bl/6 female mice and immediately after surgery switched to either Fortasyn or an isocaloric Control diet. The stroke females performed several behavioral and motor tasks before and after tMCAo and were scanned in an 11.7 Tesla MRI scanner to assess brain perfusion, integrity and functional connectivity. To assess brain plasticity, inflammation and vascular integrity, immunohistochemistry was performed after sacrifice of the mice. We found that the multinutrient intervention had diverse effects on the stroke-induced impairments in females. Similar to previous observations in male stroke mice, brain integrity, sensorimotor integration and neurogenesis benefitted from Fortasyn, but impairments in activity and motor skills were not improved in female stroke mice. Overall, Fortasyn effects in the stroked females seem more modest in comparison to previously investigated stroked male mice. We suggest that with further optimization of treatment protocols more information on the efficacy of specific interventions in stroked females can be gathered. This in turn will help with the development of (gender-specific) treatment regimens for cerebrovascular diseases such as stroke

Nachhaltige Nutzung von Energiepflanzen für eine regionale Entwicklung

Im Rahmen der Energiewende soll Biomasse verstärkt als Energieträger eingesetzt werden. Dabei ist es zentral, den Anbau von Energiepflanzen möglichst umweltschonend durchzuführen

Herd-level animal management factors associated with the occurrence of bovine neonatal pancytopenia in calves in a multicountry study

Since 2007, mortality associated with a previously unreported haemorrhagic disease has been observed in young calves in several European countries. The syndrome, which has been named ‘bovine neonatal pancytopenia’ (BNP), is characterised by thrombocytopenia, leukocytopenia and a panmyelophthisis. A herd-level case-control study was conducted in four BNP affected countries (Belgium, France, Germany and the Netherlands) to identify herd management risk factors for BNP occurrence. Data were collected using structured face-to-face and telephone interviews of farm managers and their local veterinarians. In total, 363 case farms and 887 control farms were included in a matched multivariable conditional logistic regression analysis. Case-control status was strongly associated with the odds of herd level use of the vaccine PregSure® BVD (PregSure, Pfizer Animal Health) (matched adjusted odds ratio (OR) 107.2; 95% CI: 41.0–280.1). This was also the case for the practices of feeding calves colostrum from the calf’s own dam (OR 2.0; 95% CI: 1.1–3.4) or feeding pooled colostrum (OR 4.1; 95% CI: 1.9–8.8). Given that the study had relatively high statistical power and represented a variety of cattle production and husbandry systems, it can be concluded with some confidence that no other herd level management factors are competent causes for a sufficient cause of BNP occurrence on herd level. It is suggested that genetic characteristics of the dams and BNP calves should be the focus of further investigations aimed at identifying the currently missing component causes that together with PregSure vaccination and colostrum feeding represent a sufficient cause for occurrence of BNP in calves