Competitiveness of winter wheat stands against weeds: Effects of cultivar choice, row width and drilling direction

The need for competitive crop stands can be regarded as a basic requirement for weed control, potentially reducing the need for direct control measures. One way the crop may suppress weed growth is by the restriction of light through crop shading. As part of the EU-project ²Strategies of weed control in Organic Farming² (WECOF) trials with winter wheat were carried out to evaluate the potential of wheat shading ability as a weed control measure. Factors included were cultivar, row width and drilling direction. Results of the first experimental year are presented

Effects of homeopathic and antibiotic mastitis treatment considering mediumterm parameters in an organic dairy herd

Introduction: Homeopathic treatment is a common method against bovine mastitis in organic herds. In a study conducted in a large biodyn farm in Brandenburg (D) considering 261 cases of acute or chronical mastitis, we used four different combinations of homeopathic remedies depending on clinical state of the mastitis (e.g. general findings, pain, swelling or secretion). The remedies were administrated orally. The control group was treated with antibiotics intracisternally for three days at minimum until the cow was clinically cured or defined as therapy failure. While the cure rate was calculated from clinical and laboratory data (bacterial findings and somatic cell count), the further development of the treated cows during the lactation was confirmed using monthly provided somatic cell counts of cows, mastitis and culling data. Results: We found an overall cure rate (complete healing) after administration of homeopathic remedies (H) of 21.7 % compared to 35.8 % in the antibiotically treated control group (A). Though there was an obviously poor treatment success in the homeopathy group, we found no remarkable depression of general udder health in the herd. So it was fair to assume that there must exist positive mediumterm effects of homeopathic remedies. We compared the parameters "Remain in Lactation (RIL)", "Acceptable Cell Count (ACC; < 200.000/ ml)" and analysed the reasons of culling or leaving production by other reasons. We found that there were no differences in RIL (H: 26 % vs. A: 24 %) and ACC (14 % vs. 10 %) in general six month after treatment. The risk of unsuccessful homeopathic treatment during the observing time only was higher in cases of Staph. aureus mastitis and in cows in second lactation. The most important fact was that treated cows which were classified as- subclinical infected 3 weeks after treatment- (n = 35) showed the best relative mediumterm results in the homeopathatic treatment group (ACC: 10 % vs. 0 %; RIL: 29 % vs. 7 %). We conclude that maybe the time frame of 3 weeks after treatment is not suitable to describe the effects of regulatory (homeopathic) mastitis treatment. The mediumterm effects at least six months after treatment are comparable to those after antibiotic administration. We suppose that it is possible to keep the udder health standard in a herd avoiding antibiotics

Non-LTE line-formation for CNO

Accurate atomic data have become available in the recent past due to the demands of astrophysics and fusion research. We report on the impact of such data on non-LTE line-formation calculations for CNO in early-type stars. Considerable improvement is achieved by the derivation of consistent results from practically all available spectroscopic indicators, regardless of ionization stage or spin system, and the uncertainties in the analyses are drastically reduced. Moreover, systematic trends are revealed, e.g. an increase of the NI abundances from previous studies of BA-type supergiants by a factor of two is indicated. The present work promises stringent observational constraints on chemical mixing in the course of massive star evolution. First results on BA-type supergiants in the Galaxy and the Magellanic Clouds are discussed.Comment: 6 pages, 2 figures; to be published in "CNO in the Universe", ASP Conf. Series, eds. C. Charbonnel, D. Schaerer & G. Meyne

Expected Money Growth, Markov Trends and the Instability of Money Demand in the Euro Area

This paper analyzes the recently documented instability of money demand in the euro area in the framework of a Markov switching trend model. First, we consider a standard °exible price model with stable money demand, rational expectations, and an exogenous income-money ratio which follows a Markov trend. This framework, which implies an in°uence of expected future money on prices, leads to a cointe- grating relationship between (log) prices and the (log of the) money-income ratio with a switching intercept term. Of course, this likely leads to a rejection of coin- tegration by standard tests and to the erroneous conclusion of an unstable money demand. Second, a more general model allowing for endogeneity and more general dynamics is estimated with Bayesian methods for euro area data from 1975-2003. This exercise provides support for our model and a stable demand for M3 in the euro area

Soil health and ecosystem services: Lessons from sub-Sahara Africa (SSA)

Management practices to improve soil health influence several ecosystem services including regulation of water flows, changes in soil biodiversity and greenhouse gases that are important at local, regional and global levels. Unfortunately, the primary focus in soil health management over the years has been increasing crop productivity and to some extent the associated economics and use efficiencies of inputs. There are now efforts to study the inter-relationship of associated ecosystem effects of soil health management considering that sustainable intensification cannot occur without conscious recognition of these associated non-provisioning ecosystem services. This review documents the current knowledge of ecosystem services for key management practices based on experiences from agricultural lands in sub-Sahara Africa (SSA). Here, practicing conservation agriculture (CA) and Integrated Soil fertility management (ISFM) have overall positive benefits on increasing infiltration (> 44), reducing runoff (> 30%) and soil erosion (> 33%) and increases soil biodiversity. While ISFM and Agroforestry increase provisioning of fuelwood, fodder and food, the effect of CA on the provisioning of food is unclear. Also, considering long-term perspectives, none of the studied soil health promoting practices are increasing soil organic carbon (SOC). Annual contributions to greenhouse gases are generally low (< 3 kg N2O ha−1) with few exceptions. Nitrogen leaching vary widely, from 0.2 to over 200 kg N ha−1 and are sometimes inconsistent with N inputs. This summary of key considerations for evaluating practices from multiple perspectives including provisioning, regulating, supporting and cultural ecosystem services is important to inform future soil health policy and research initiatives in SSA

Provenance-based validation of E-science experiments

E-Science experiments typically involve many distributed services maintained by different organisations. After an experiment has been executed, it is useful for a scientist to verify that the execution was performed correctly or is compatible with some existing experimental criteria or standards. Scientists may also want to review and verify experiments performed by their colleagues. There are no existing frameworks for validating such experiments in today's e-Science systems. Users therefore have to rely on error checking performed by the services, or adopt other ad hoc methods. This paper introduces a platform-independent framework for validating workflow executions. The validation relies on reasoning over the documented provenance of experiment results and semantic descriptions of services advertised in a registry. This validation process ensures experiments are performed correctly, and thus results generated are meaningful. The framework is tested in a bioinformatics application that performs protein compressibility analysis

Are homeopathics able to replace antibiotics in the therapy of bovine mastitis? A placebo controlled randomized double-blind trial

To evaluate the effects of homeopathics on clinical mastitis cows and herd udder health this investigation was conducted in a Brandenburg bio-dyn herd of about 300 cows in two phases using a randomized doubleblind control trial design. After the first part in July 2002 the results preliminarily were evaluated and then the whole concept due to unsatisfying results was adapted. In Phase 1 a number of 121 clinical mastitis cases with 137 affected quarters matched the including criteria, in Phase 2 the number was 126 cows with 148 quarters. These animals were allocated to a code number which classified the case to Verum (n=65 and n=60) or placebo group (n=56 and n=66). In case of clinical mastitis cows were treated either by the oral dilution contending the required combined homeopathics or placebo. Animals were treated twice a day for 5 to 14 days (Phase 2: 1 to 7 days) depending on development of disease. In case of therapy failure in Phase 1 all animals were treated by an not coded homeopathic preparation and in Phase 2 by antibiotics according to bacteriological findings. Milk samples (double samples) for bacteriological and cell count investigation were taken before treatment (M1), 4 to 5 weeks after treatment termination (M2) and 7 to 8 weeks after treatment termination (M3). To evaluate the herd situation additional samples were taken after calving and before dry off. Healing criteria on the cow level was the clinical cure without secondary therapy and release to production. On quarter level the cure was determined by bacterial findings (BCR) and additional by cytological findings. A quarter was determined as „completely cured“, if no bacteria were found AND the cell count was below 100.000/ml. To assess the reduction of antibiotics within the concept it was hypothetically assumed that the mastitis cows had an average milk yield of 20,5 kg per day, was treated under conventional conditions by antibiotics over 3 days with a mean withdrawal time of 5 days (organic conditions x2). Afterwards, these theoretical values were compared to the extrapolated antibiotics input within our concept. Results While there is no difference between the cows in phase 1, on quarter level the verum group showed a significant higher complete cure rate than placebo group in Phase 2. These results are balanced by additional antibiotics treatment in case of therapy failure in the placebo group. The complete cure rate in the verum group after 8 weeks was 32% compared to 13% in placebo group (p<0.05). The limited cure results in single cows did not lead to an udder health depression of the herd. During the study the mean of somatic cell count could decreased by 100.000 cells/ml while the milk yield increased slightly by 250 kg/cow to 6.500 kg/cow/year. The number of actual antibiotic treatments during observation time compared to the number of mastitis cases which would be treated by antibiotics under conventionel conditions showed a reduction by 75%. The extrapolated reduction of milk loss by withdrawal was 25.000kg and the reduction of contaminated milk during treatment time was 13.100 kg per year for the herd. Discussion and Conclusions The increasing cure rates in the second part of the study are influenced by the enhancement of environmental preconditions in combination with the simplified therapy scheme. The therapists seemed to be more familiar with the fixed combinations of homeopathics so that positive effects of the homeopathics can be seen in this phase. After additional antibiotic treatments in case of therapy failure in specific infections (i.e. streptococci and staph. aureus) the cure rates could be elevated to a satisfying level. This fact shows that the limited and controlled use of antibiotics in organic herds can be helpful in the mastitis control. Regardless the conceptual modification to an antibiotic emergency concept, the massive reduction of antibiotics in combination with an increase of herd udder health justifies the therapy protocol in the second phase of the study. Hypothetically, the self cure of the animals is higher than known. The interaction between farmer or therapist and the cow could be a crucial criterion for the positive development of disease. As a conclusion, the integrated system consisting of preventive herd measures and complementary therapy added by limited antibiotic therapy. The precondition for the success is the attendance to optimize environmental conditions. The therapy system should be transparent, simple and easy to use. However, it is necessary to reflect every single mastitis case as a special one

Evaluation of handheld X-ray fluorescence spectroscopy results of Roman copper alloy brooches by using archaeological typology

As part of the Late Roman research project in Belgium and the Netherlands, 187 Roman copper alloy brooches were analyzed by means of handheld X-ray fluorescence (hXRF) spectroscopy in order to explore the relationship between composition, production organization and change over time. The selected brooch type is called ‘the crossbow brooch’, which is an artifact that is closely associated with the Late Roman elite, frequently occurring in many portraits on mosaics, sculptures and fresco’s from the 4th to the 6th century. The biography of the crossbow brooch, however, starts in the 3rd century as a simple military object and develops into one of the most significant symbols of Roman state authority in the 5th and 6th century. The hXRF spectrometer provided a non-destructive, mobile, quick and inexpensive way of analyzing these brooches that were part of valued museum and archaeological collections. The samples were selected to cover the entire chronological, geographical and stylistic variation of these brooches in the study area. Each object was measured in three to five locations to compensate the heterogeneity of the copper alloy and the geometry of the object. The compositional results revealed a continuous variation that crosses copper alloy boundaries with no evident groups or trends, as is often the case for archaeological data sets. To move beyond a black box approach that provides little insights, the typological information was added to interpret the compositional data. An archaeological typology is constructed based on observed variations that represent expressions of choices made by craftsmen and workshops. In other words, typology contains information that can help explain compositional variation caused by different manufacturing techniques or production centers, changes in consumer demands, as well as factor in aspects of chronology and regionality. Consequently, the division of the compositional data in the six types of crossbow brooches allowed to distinguish patterns that indicated changes in production organization related to social context. The combination of typology and compositional data allowed to characterize the different phases in the crossbow brooches’ life history, which in its turn contributed to the larger narrative of the rise to power of the military elite in the Late Roman period

Triple the gamma -- A unifying shrinkage prior for variance and variable selection in sparse state space and TVP models

Time-varying parameter (TVP) models are very flexible in capturing gradual changes in the effect of a predictor on the outcome variable. However, in particular when the number of predictors is large, there is a known risk of overfitting and poor predictive performance, since the effect of some predictors is constant over time. We propose a prior for variance shrinkage in TVP models, called triple gamma. The triple gamma prior encompasses a number of priors that have been suggested previously, such as the Bayesian lasso, the double gamma prior and the Horseshoe prior. We present the desirable properties of such a prior and its relationship to Bayesian Model Averaging for variance selection. The features of the triple gamma prior are then illustrated in the context of time varying parameter vector autoregressive models, both for simulated datasets and for a series of macroeconomics variables in the Euro Area