Estimation of Commodity Specific Production Costs Using German Farm Accountancy Data

A central problem in estimating per unit costs of production originates from the fact that most farms produce multiple outputs and standard farm-accounting data are only available at the whole-farm level. The seemingly unrelated regression (SUR) approach is used to estimate per unit production costs based on German farm accountancy data. Special emphasis is put on outlier detection prior to the estimation of production costs to increase the robustness of the results. Outlier observations are identified based on the Mahalanobis distance for each observation on the data set. It was observed that less negative cost coefficients are estimated after the exclusion of the outliers. The time series analysis of cost estimation based on SUR regression shows the costs of arable crops after 2004, affected by rising prices of fertilizer, seeds and energy, while the increase of livestock production costs after 2006 is attributed to feed costs.Multi-output, outlier detection, production costs, Seemingly Unrelated Regression, Agricultural Finance,

Can Guided Notes Support Students’ Note-taking in Mathematics Lectures?

In traditional mathematics lectures the instructor normally writes the definitions, theorems, and proofs covered on the board, and gives informal oral explanations that help to make sense of them. The students have to take notes. However, there are serious problems concerning students’ note-taking in traditional mathematics lectures. Students often cannot think about the information presented during the lecture as they are busy writing. Making sense of the content later is also difficult because many students do not include the lecturer’s oral explanations in their notes. One approach to addressing these problems can be the use of guided notes: a modified version of the instructor’s notes with certain blanks the students have to fill in during the lecture. We investigated to what extent guided notes can support students in their note-taking in mathematics lectures in a study using a mixed-method design. This study provides on the one hand quantitative data suggesting that guided notes are perceived as beneficial by many students for several aspects of their note-taking. On the other hand, it offers qualitative data illustrating how the use of guided notes can influence these aspects. The results indicate in particular that the use of guided notes can address some of the problems concerning students’ note-taking in traditional mathematics lectures, while it can also lead to new problems that one needs to be aware of.Humboldt-Universität zu Berlin (1034)Peer Reviewe

Continental Scale Modelling of Water Quality in Rivers

Global and continental scale modelling has been confined to water quantity (e.g. WaterGAP - Water Global Assessment and Prognosis (Alcamo et al. 2003), GWAVA - Global Water AVailability Assessment (Meigh et al, 1999)). Here we describe an approach to include water quality at these scales within the WaterGAP model. The application is to the pan-European area and is being carried out within the EU-funded SCENES Project which has the principal goal of developing new scenarios of the future of freshwater resources in Europe. The model operates on 5x5 arc-minute grid squares. Water flows in and between grid cells are provided by WaterGAP. The water quality loadings into the river system comprise point sources (domestic effluent, manufacturing discharges and urban runoff) and diffuse sources (runoff from land and scattered settlements not connected to the public sewerage system). Point source loadings are calculated for each country using easily available datasets. For example, the domestic load is a per capita emission factor times by country population multiplied by the percentage of the population connected to the sewage system, which is then reduced by the amount removed in each of three types of sewage treatment (primary, secondary and tertiary). Data on the amount treated in different types of sewage works is set for each country, while the amount removed by treatment types will vary with the water quality variable being modelled. Country level data is converted to grid square data required by the model, according to the population in each grid square. Diffuse sources from land are calculated by regression models based on runoff and land use (e.g. numbers of livestock) for each model grid square. The modelling system has currently been set up to simulate biochemical oxygen demand (BOD) and total dissolved solids. The model was tested against measured longitudinal profiles and time series data for BOD on contrasting rivers e.g. the River Thames (UK) driven by domestic loading and the River Ebro (Spain) with a high share of discharges from livestock farming. Further developments will see the inclusion of total nitrogen (TN), total phosphorus (TP) and dissolved oxygen. Within the SCENES project a set of future scenarios reflecting different outlooks on Europe has been developed, called “Economy First”, “Fortress Europe”, “Sustainability Eventually” and “Policy Rules”. An Expert Panel was used to suggest what these futures would mean for drivers of water quantity and water quality across pan-Europe. We have projected how changes in percentage population connected to sewers, the level of sewage treatment and population would change loadings from domestic effluent for TN, TP and BOD. In time, these will be used to predict future water quality in European rivers

Organic farming: implications for costs of production and provisioning of environmental services

The report is part of the project 'Farm Accountancy Cost Estimation and Policy Analysis of European Agriculture' (FACEPA). The overall aim of this report is to contrast organic and conventional forms of commodity production in terms of costs and environmental performance. Specific objectives are to apply the General Cost of Production Model (GECOM) developed in the FACEPA project to organic farms, to compare GECOM results for organic farming to data from other national studies as part of a (quasi-)validation, to discuss production costs in organic farming in the light of the structure of the organic farming sector and the respective policy environment in selected EU Member States, and to explore the potential of FADN systems for deriving environmental impacts at farm level, calculating and comparing selected indicators for organic farms. The report is structured as follows: First, a short overview is given of the structure of the organic farming sector and the respective policy environment in selected study countries (Chapter 2). Chapter 3 provides a description and discussion of production costs in organic farming collected from various other national sources, paying specific attention to the impact of different methodological approaches used in the available studies. In Chapter 4, the GECOM estimations for fully organic farms of EU FADN are illustrated and compared to other national production cost data to provide a quasi-validation of the GECOM estimates. Chapter 5 presents a comparison of the GECOM estimates for production costs in organic and conventional farming. The final Chapter 6 then illustrates the potential of identifying environmental impacts based on FADN data

Dietary Supplement Use in Young Elite Athletes and School Children Aged 11 to 13 Years: A Cross-Sectional Study Design

Objective: Information about dietary supplement (DS) use in young German athletes beginning their sporting career is scarce and possible differences to their non-athlete counterparts are unknown. Therefore, the purpose of this study was to analyze DS use in young elite German athletes (A) and non-athlete (NA) controls. Method: During pre-participation examinations, 562 athletes (323m/239f, 11.7±0.6 years) and 69 non-athletes (12m/57f; 12.5±0.5 years) answered a standardized questionnaire analyzing the prevalence of DS use, reasons for intake, and sources of information. Group differences were analyzed with Chi² test (α=0.05). Results: 14% of A and 20% of NA used DS, with no statistically significant differences between groups (p=0.231). Magnesium (A: 35%; NA: 36%) and calcium (A: 28%; NA: 7%) were the most frequently used minerals. Vitamin C (A: 37%; NA: 36%) and multi-vitamin supplements (A: 40%; NA: 29%) were the most often used vitamins. The main reason for DS intake was for health improvement (A: 77%; NA: 71%). The main information source was cited as their parents (A: 66%, NA: 71%). Discussion: Young German athletes beginning their sporting career show similar supplementation habits astheir non-athletic counterparts. Compared to the literature, prevalence of DS use amongst the observed athletes is low. This is likely to increase with age and growing performance level. Keeping that and possible doping infractions or overdoses in mind, nutritional education should start early in ones sporting career and should include the parents

Oligodendroglial GABAergic Signaling: More Than Inhibition!

GABA is the main inhibitory neurotransmitter in the CNS acting at two distinct types of receptor: ligand-gated ionotropic GABAA receptors and G protein-coupled metabotropic GABAB receptors, thus mediating fast and slow inhibition of excitability at central synapses. GABAergic signal transmission has been intensively studied in neurons in contrast to oligodendrocytes and their precursors (OPCs), although the latter express both types of GABA receptor. Recent studies focusing on interneuron myelination and interneuron-OPC synapses have shed light on the importance of GABA signaling in the oligodendrocyte lineage. In this review, we start with a short summary on GABA itself and neuronal GABAergic signaling. Then, we elaborate on the physiological role of GABA receptors within the oligodendrocyte lineage and conclude with a description of these receptors as putative targets in treatments of CNS diseases

Reliability of a Fully Automated Interpretation of

Background: Analysis of γ-H2AX foci is a promising approach to evaluate exercise-induced DNA damage. However, baseline levels and day-to-day variability of γ-H2AX foci have not been investigated in healthy subjects at rest. Methods: Blood was taken from eight moderately trained healthy males (29 ± 3 yrs, 1.84 ± 0.03 m, and 85 ± 6 kg) at two separate days (M1/M2) after 24-hour exercise cessation. Number of γ-H2AX foci per 100 lymphocytes (N), number of foci per affected lymphocyte (NAL), percentage of affected lymphocytes (PAL), and diameter (D) of γ-H2AX foci were analyzed (mean ± SD). Differences between M1 and M2 were analyzed using paired t-tests (α = 0.05). Day-to-day variability was evaluated by calculating the coefficients of variation (CV%), bias, and limits of agreement (LoA). Results: There were no statistically significant differences between M1 (N: 7.6 ± 4.4, NAL: 1.2 ± 0.2, PAL: 5.9 ± 2.6%, and D: 0.63 ± 0.07) and M2 (N: 8.4 ± 4.6, NAL: 1.3 ± 0.1, PAL: 6.9 ± 4.2%, and D: 0.66 ± 0.06). CV was calculated to be 98.5% (N), 88.9% (PAL), 11.3% (NAL), and 8.0% (D). Bias (LoA) was 0.75 (-15.2/13.7), -0.02 (-0.36/0.33), -1.0 (-11.9/9.9), and -0.04 (-0.16/0.09), respectively. Conclusions: Background level in healthy subjects is approximately 0.07 to 0.09 γ-H2AX foci/cell. NAL and D are reliable measures

Prenatal ultrasound screening for fetal anomalies and outcomes in high-risk pregnancies due to maternal HIV infection : a retrospective study

Objective: To assess the prevalence of prenatal screening and of adverse outcome in high-risk pregnancies due to maternal HIV infection. Study design: The prevalence of prenatal screening in 330 pregnancies of HIV-positive women attending the department for prenatal screening and/or during labour between January 1, 2002 and December 31, 2012, was recorded. Screening results were compared with the postnatal outcome and maternal morbidity, and mother-to-child transmission (MTCT) was evaluated. Results: One hundred of 330 women (30.5%) had an early anomaly scan, 252 (74.5%) had a detailed scan at 20–22 weeks, 18 (5.5%) had a detailed scan prior to birth, and three (0.9%) had an amniocentesis. In seven cases (2.12%), a fetal anomaly was detected prenatally and confirmed postnatally, while in eight (2.42%) an anomaly was only detected postnatally, even though a prenatal scan was performed. There were no anomalies in the unscreened group. MTCT occurred in three cases (0.9%) and seven fetal and neonatal deaths (2.1%) were reported. Conclusion: The overall prevalence of prenatal ultrasound screening in our cohort is 74.5%, but often the opportunity for prenatal ultrasonography in the first trimester is missed. In general, the aim should be to offer prenatal ultrasonography in the first trimester in all pregnancies. This allows early reassurance or if fetal disease is suspected, further steps can be taken