Chance Constrained Optimal Power Flow Using the Inner-Outer Approximation Approach

In recent years, there has been a huge trend to penetrate renewable energy sources into energy networks. However, these sources introduce uncertain power generation depending on environmental conditions. Therefore, finding 'optimal' and 'feasible' operation strategies is still a big challenge for network operators and thus, an appropriate optimization approach is of utmost importance. In this paper, we formulate the optimal power flow (OPF) with uncertainties as a chance constrained optimization problem. Since uncertainties in the network are usually 'non-Gaussian' distributed random variables, the chance constraints cannot be directly converted to deterministic constraints. Therefore, in this paper we use the recently-developed approach of inner-outer approximation to approximately solve the chance constrained OPF. The effectiveness of the approach is shown using DC OPF incorporating uncertain non-Gaussian distributed wind power

Certification of a Reference Material with Eschericia Coli O157 (NCTC 12900) at a level of 4 Colony forming Unit per Material Sphere, IRMM-351

This report describes the certification of a reference material (IRMM-351) of Escherichia coli O157. Certified Reference Materials (CRMs) for microbiological analysis are indispensable tools for development and validation of detection methods and for the implementation and support of internal and external quality control in the area of microbiological analysis. Each vial contains one material sphere of E. coli O157. The homogeneity and stability (at 4 °C, -20 °C and -70 °C) of the batch was assessed by monitoring colony forming units (cfu) on nutrient agr (NA) and eterohemolysin agar (EhlyA) of selected vials by colony counting. The material is not stable at 4 °C but no instability was detected when stored at -20 °C for up to 12 months and at -70 °C for up to 54 months. The batch was characterised by six laboratories to determine a certified value of cfu per vial on NA and EhlyA. The certified value is 4 cfu on both agars with an expanded uncertainty of 2 using a coverage factor k = 2, corresponding to a level of confidence of about 95 %. DNA sequence analysis of the coding region for the fliC gene identified the material as E. coli O157.JRC.D.2-Reference material

Certification of a Reference Material with Salmonella Enteritidis (NCTC 12694) at a Level of 5 Colony Forming Units on Nutrient Agar and 4 Colony Forming Units on Xylose Lysine Deoxycholate Agar, IRMM-352

This report describes the certification of a reference material (IRMM-352) of Salmonella Enteritidis. Certified Reference Materials (CRMs) for microbiological analysis are indispensable tools for development and validation of detection methods and for the implementation and support of internal and external quality control in the area of microbiological analysis. Each vial contains one material sphere of S. enteritidis. The homogeneity and stability (at 4 °C, -20 °C and -70 °C) of the batch was assessed by monitoring colony forming units (cfu) on nutrient agar (NA) and xylose lysine deoxycholate (XLD) agar of selected vials by colony counting. The material is not stable at 4 °C byt no instability was detected when stored at -20 °C for up to 12 months and at -70 °C for up to 54 months. The batch was characterised by six laboratories to determine a certified value of cfu per vial on NA and XLD agar. A quite considerable performance difference of both agars was observed. The certified value is 5 cfu on NA with an expanded uncertainty of 2 and 4 cfy on XLD agar with an expanded incertainty of 2 using a coverage factor k = 2, corresponding to a level of confidence of about 95 %. DNA sequence analysis of the coding region for the sefA gene identified the material as S. enteritidis.JRC.D.2-Reference material

Assessment, Evaluation, and Grading: A Reflection on My Radicalization

The COVID-19 pandemic forced instructors to adapt their assessment practices. For this author, that adaptation led to a reconsideration of evaluation systems, given the ways in which such systems can interfere with learning and perpetuate inequities. The author describes resulting changes in her grading of student work and evaluation of faculty colleagues

Performance measures of net-enabled hypercompetitive industries: the case of tourism

This paper investigates the theory and practise of e-metrics. It examines the tourism sector as one of the most successful sectors on-line and identifies best practice in the industry. Qualitative research with top e-Marketing executives demonstrates the usage and satisfaction levels from current e-metrics deployment, selection of e-metrics for ROI calculation as well as intention of new e-metrics implementation and future trends and developments. This paper concludes that tourism organizations gradually realise the value of e-measurement and are willing to implement e-metrics to enable them evaluate the effectiveness of their planning processes and assess their results against their short and the long term objectives

Butrepyrazinone, a New Pyrazinone with an Unusual Methylation Pattern from a Ghanaian Verrucosispora sp. K51G

We report the structural characterization of a new pyrazinone analogue; butrepyrazinone, which was isolated from a new actinomycete strain Verrucosispora sp. K51G recovered from Ghanaian mangrove river sediment. Spectroscopy-guided fractionation led to the isolation of a compound from the fermentation culture and a combination of NMR spectroscopy, high-resolution mass spectrometry and computer-aided calculations revealed that butrepyrazinone (10) possesses an unusual methylation pattern on the pyrazinone ring. Butrepyrazinone (10), however, displayed no antibacterial activity against Gram-positive S. aureus ATCC 25923, the Gram-negative E. coli ATCC 25922 and a panel of clinical isolates of methicillin-resistant S. aureus (MRSA) strains, suggesting that 10 may act as a signal molecule for this strain. Although the same molecule has been synthesized previously, this is the first report to disclose the discovery of butrepyrazinone (10) from nature

Human sperm heads harbor modified YsRNA as transgenerationally inherited non-coding RNAs

Most epigenetic information is reprogrammed during gametogenesis and early development. However, some epigenetic information persists and can be inherited, a phenomenon that is common in plants. On the other hand, there are increasing examples of epigenetic inheritance in metazoans, especially for small non-coding RNAs. The presence of regulatory important RNAs in oocytes is undisputed, whereas the corresponding RNA payload in spermatozoa and its regulatory influence in the zygote and early embryogenesis is largely enigmatic. For humans, we herein describe small YRNA fragments (YsRNA) as a paternal contribution to the zygote. First, we trace the biogenesis of these YsRNAs from the source YRNAs with respect to the 5′ and 3′ modifications. Both the length and modifications make these YsRNAs reminiscent of canonical piRNAs that are not derived from piRNA clusters. Second, from the early stages of spermatogenesis to maturation in the epididymis, we observe distinct YsRNA profile dynamics in the male germline. We detected YsRNAs exclusively in mature sperm heads, the precursor of the male pronucleus in the zygote, suggesting an important role of the epididymis as a site for transmitting and modification of epigenetic information in the form of YsRNA between soma and germline in humans. Since this YsRNA-based epigenetic mechanism is effective across generations, we wondered whether this phenomenon of epigenetic inheritance has an adaptive value. Full-length YRNAs bind to Ro60, an RNA chaperone that additionally binds to non-coding RNAs. We described the profiles of non-coding RNAs bound to Ro60 in the human sperm head and detected specific binding profiles of RNA to Ro60 but no YRNA bound to Ro60. We hypothesize that the sperm head Ro60 system is functional. An adaptive phenotype mediated by the presence of a large amount of YsRNA in the sperm head, and thus as a paternal contribution in the zygote, might be related to an association of YsRNA with YRNA that prevents the adoption of a YRNA secondary structure capable of binding to Ro60. We hypothesize that preventing YRNAs from acting as Ro60-associated gatekeepers for misfolded RNAs in the zygote and early development may enhance RNA chaperoning and, thus, represent the adaptive molecular phenotype

How to start with big data - a multiple case study

As part of an advancing digitalization, many enterprises feel the need to explore the possibilities big data may provide for their business. However, only a few companies use big data applications productively, despite its high expected potential. How companies examine the possibilities of big data, is therefore a highly interesting and relevant question. Based on a multiple case study we identify three different approaches: Companies either initially focus entirely on business aspects, or on a systematic build-up of a big data technology and data platform. Innovation adoption research is used as a theoretical basis