The common data acquisition platform in the Helmholtz Association

Various centres of the German Helmholtz Association (HGF) started in 2012 to developa modular data acquisition (DAQ) platform, covering the entire range from detector readout todata transfer into parallel computing environments. This platform integrates generic hardwarecomponents like the multi-purpose HGF-Advanced Mezzanine Card or a smart scientific cameraframework, adding user value with Linux drivers and board support packages. Technically the scopecomprises the DAQ-chain from FPGA-modules to computing servers, notably frontend-electronicsinterfaces, microcontrollers and GPUs with their software plus high-performance data transmissionlinks. The core idea is a generic and component-based approach, enabling the implementationof specific experiment requirements with low effort. This so called DTS-platform will supportstandards like MTCA.4 in hard- and software to ensure compatibility with commercial components.Its capability to deploy on other crate standards or FPGA-boards with PCI express or Ethernetinterfaces remains an essential feature.Competences of the participating centres are coordinated in order to provide a solid technological basis for both research topics in the Helmholtz Programme “Matter and Technology”:“Detector Technology and Systems” and “Accelerator Research and Development”. The DTSplatform aims at reducing costs and development time and will ensure access to latest technologiesfor the collaboration. Due to its flexible approach, it has the potential to be applied in other scientificprograms

Heterogeneous hydride pyrolysis in a chemical beam epitaxy cracker cell and growth of high quality InP

The decomposition of phosphine and arsine in a chemical beam epitaxy cracker cell was investigated with a quadrupole mass spectrometer. We have determined the kinetical parameters for a unimolecular reaction of the first order, i.e. the activation energy and frequency factor, from the decomposition efficiency as a function of temperature. These results are compared with data from literature. We find the lowest activation energies ever reported for the hydride pyrolysis, namely 72 and 48 kJ/mol for phosphine and arsine, respectively. This is due to the heterogeneous decomposition on catalytic molybdenum baffles inside the cracker cell. Additionally, we have studied the impurity incorporation in epitaxially grown bulk InP layers in relation to the efficiency of this particular molybdenum containing cracker cell. Impurity levels were determined by fitting calculated Hall values to experimental data. The best quality is achieved for the cracker temperature at which the efficiency starts to saturate. At this cracker temperature, optimized mass flow rates resulted in InP layers with a maximum mobility of 186¿000 cm2/V¿s and impurity concentrations in the low 1014 cm-3 range

Towards a full-reference, information-theoretic quality assessment method for X-ray images

This work aims at defining an information-theoretic quality assessment technique for cardiovascular X-ray images, using a full-reference scheme (relying on averaging a sequence to obtain a noiseless reference). With the growth of advanced signal processing in medical imaging, such an approach will enable objective comparisons of the quality of processed images. A concept for describing the quality of an image is to express it in terms of its information capacity. Shannon has derived this capacity for noisy channel coding. However, for X-ray images, the noise is signal-dependent and non-additive, so that Shannon's theorem is not directly applicable. To overcome this complication, we exploit the fact that any invertible mapping on a signal does not change its information content. We show that it is possible to transform the images in such a way that the Shannon theorem can be applied. A general method for calculating such a transformation is used, given a known relation between signal mean and noise standard deviation. After making the noise signal-independent, it is possible to assess the information content of an image and to calculate an overall quality metric (e.g. information capacity) which includes the effects of sharpness, contrast and noise. We have applied this method on phantom images under different acquisition conditions and computed the information capacity for those images. We aim to show that the results of this assessment are consistent with variations in noise, contrast and sharpness, introduced by system settings and image processing

Improving dietary intake during lunch through the provision of a healthy school lunch at Dutch primary schools : Design of a pretest-posttest effectiveness study

Background: Since there is a shift from eating lunch at home to eating lunch at primary schools in the Netherlands, providing a school lunch may be an important opportunity to improve the diet quality of Dutch children. Therefore, the aim of this Healthy School Lunch project is to encourage healthy eating behavior of children at primary schools by offering a healthy school lunch, based on the guidelines for a healthy diet. In this study, two research questions will be addressed. The first research question is: What and how much do children consume from a self-served school lunch and how do they evaluate the lunch? The second research question is: Do children compensate healthier school lunches by eating less healthy outside school hours? The purpose of this paper is to report the rationale and study design of this study. Methods: In the Healthy School Lunch project children in grades 5-8 (aged 8-12 years) of three primary schools in the Netherlands will receive a healthy school lunch for a 6-month period. To answer research question 1, lunch consumption data will be collected at baseline and again at 3- A nd 6-months. This will be measured with lunch photos and questionnaires among children. To answer the second research question, a quasi-experimental, pre-test post-test intervention-comparison group design (3 intervention schools and 3 comparison schools) will be carried out. Potential compensation effects will be measured with a single brief questionnaire among parents at the three intervention and three comparison schools at month 6 of the lunch period. The school lunch will also be evaluated by parents (discussion groups) and teachers and support staff (brief questionnaires). Discussion: Results of this study will provide valuable information to influence future school lunch interventions and policies. Trial registration: This study is registered at the Netherlands trial register (NTR): Trialregister.nl, Trial NL7402 (NTR7618), registered retrospectively at 2018-11-13.</p

Agricultural Microcredit and Household Vulnerability in Rural Malawi

textabstractSixteen girls with Turner syndrome (TS) were treated for 4 years with biosynthetic growth hormone (GH). The dosage was 4IU/m2 body surface s.c. per day over the first 3 years. In the 4th year the dosage was increased to 61 U/m2 per day in the 6 girls with a poor height increment and in 1 girl oxandrolone was added. Ethinyl oestradiol was added after the age of 13. Mean (SD) growth velocities were 3.4 (0.9), 7.2 (1.7), 5.3 (1.3), 4.3 (2.0) and 3.6 (1.5) cm/year before and in the 1st, 2nd, 3rd and 4th year of treatment. Skeletal maturation advanced faster than usual in Turner patients especially in the youger children. Although the mean height prediction increased by 5.6 cm and 11 of the 16 girls have now exceeded their predicted height, the height of the 4 girls who stopped GH treatment exceeded the predicted adult height by only 0 to 3.4 cm

Impact of lifelong exercise training on endothelial ischemia-reperfusion and ischemic preconditioning in humans.

Reperfusion is essential for ischemic tissue survival, but causes additional damage to the endothelium (i.e. ischemia-reperfusion [IR] injury). Ischemic preconditioning (IPC) refers to short repetitive episodes of ischemia that can protect against IR. However, IPC efficacy attenuates with older age. Whether physical inactivity contributes to the attenuated efficacy of IPC to protect against IR injury in older humans is unclear. We tested the hypotheses that lifelong exercise training relates to 1) attenuated endothelial IR and 2) maintained IPC efficacy that protects veteran athletes against endothelial IR. In 18 sedentary male individuals (SED, 20 years, 63±7 years) and 20 veteran male athletes (ATH, >5 exercise hours/week for >20 years, 63±6 years), we measured brachial artery endothelial function with flow-mediated dilation (FMD) before and after IR. We induced IR by 20-minutes of ischemia followed by 20-minutes of reperfusion. Randomized over 2 days, participants underwent either 35-minute rest or IPC (3 cycles of 5-minutes cuff inflation to 220 mmHg with 5-minutes of rest) before IR. In SED, FMD decreased after IR (median [interquartile range]): (3.0% [2.0-4.7] to 2.1% [1.5-3.9], P=0.046) and IPC did not prevent this decline (4.1% [2.6-5.2] to 2.8% [2.2-3.6],P=0.012). In ATH, FMD was preserved after IR (3.0% [1.7-5.4] to 3.0% [1.9-4.1], P=0.82) and when IPC preceded IR (3.2% [1.9-4.2] to 2.8% [1.4-4.6],P=0.18). These findings indicate that lifelong exercise training is associated with increased tolerance against endothelial IR. These protective, preconditioning effects of lifelong exercise against endothelial ischemia-reperfusion may contribute to the cardio-protective effects of exercise training

Mobile HTS SQUID System for Eddy Current Testing of Aircraft

In Non-Destructive Evaluation (NDE), eddy current techniques are commonly used for the detection of hidden material defects in metallic structures. Conventionally, one works with an excitation coil generating a field at a distinct frequency. The eddy currents are deviated by materials flaws and the resulting distorted field is sensed by a secondary coil. Because of the law of induction, this technique has its limitations in the low frequency range. This leads to a decrease of the Probability of flaw Detection (POD) in larger depths

The skeletons of free distributive lattices

AbstractThe skeletons of free distributive lattices are studied by methods of formal concept analysis; in particular, a specific closure system of sublattices is elaborated to clarify the structure of the skeletons. Up to five generators, the skeletons are completely described