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Alexandra Florina Levărdă and Ioana Matache

Abstract

This catalogue presents data on 15 Romanian sphecid wasp species (Hymenoptera: Apoidea: Sphecidae) preserved in the Hymenoptera Collection of “Grigore Antipa” National Museum of Natural History, Bucharest. The collecting data, general distribution, distribution in Romania and some ecological aspects are provided for each species.

Open access

Jiří Hájek and Josef Jelínek

Abstract

The cryptic slime-mold beetle Sphindus cf. rendilianus Lesne, 1922, described originally from Kenya, and so far known only from the holotype, is recorded from Socotra Island based on five specimens from recent collecting efforts. This is the first report of the family Sphindidae from the archipelago.

Open access

Rastislav Telgarsky

Abstract

Observation of nature and design of experiments inspires new mathematical investigations often resulting in new computer algorithms and constructions of new devices. This paper attempts to collect many cases where mathematics is inspired by the nature, and leads to direct applications in engineering.

Open access

János Folláth

Abstract

Modern lattice-based cryptosystems require sampling from discrete Gaussian distributions. We review lattice based schemes and collect their requirements for sampling from discrete Gaussians. Then we survey the algorithms implementing such sampling and assess their practical performance. Finally we draw some conclusions regarding the best candidates for implementation on different platforms in the typical parameter range

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Romi Shamoyan and Seraphim Maksakov

Abstract

The survey collects many recent advances on area Nevanlinna type classes and related spaces of analytic functions in the unit disk concern- ing zero sets and factorization representations of these classes and discusses approaches, used in proofs of these results.

Open access

The ›Head of Household‹

A Long Normative History of a Statistical Category in the U.K

Kerstin Brückweh

The household forms an important category in social science research. It is used to collect data, to classify it and to represent the results. In 2009, for example, 3.48 % of U.K. households were classified as the most influential and wealthiest individuals in the U.K.; at the other end 5.16 % of U.K. households formed the most disadvantaged people. While the households in the first group represented positions of power in the private and public sector and could afford luxury items, the latter had a budget to only cope with the daily necessities. Experian

Open access

Alexandra Ostmann, Sarah Schnurr and Pedro Martínez Arbizu

Abstract

Sediment samples and hydrographic conditions were studied at 28 stations around Iceland. At these sites, Conductivity-Temperature-Depth (CTD) casts were coducted to collect hydrographic data and multicorer casts were conducted to collect data on sediment characteristics including grain size distribution, carbon and nitrogen concentration, and chloroplastic pigment concentration. A total of 14 environmental predictors were used to model sediment characteristics around Iceland on regional scale. Two approaches were used: Multivariate Adaptation Regression Splines (MARS) and randomForest regression models. RandomForest outperformed MARS in predicting grain size distribution. MARS models had a greater tendency to over-and underpredict sediment values in areas outside the environmental envelope defined by the training dataset. We provide first GIS layers on sediment characteristics around Iceland, that can be used as predictors in future models. Although models performed well, more samples, especially from the shelf areas, will be needed to improve the models in future.

Open access

Asma Abdul Aziz, Mehmood Ul Hassan, Hisham Dzakiria and Qaisar Mahmood

Abstract

The study explores growing trends of using mobile in English language learning among higher secondary school learners in Pakistan. A survey is conducted to collect data from randomly selected students in district Okara (Punjab), Pakistan. Questionnaire based on five likert scale used to collect quantitative data. Analysis done on SPSS, to acquire mean score and frequency analysis reveals that higher secondary school students of English have great tendency for using mobile to learn English. Besides Students’ perception as obtained from survey prove that using mobile for English language learning makes their job easy and they are able to develop their listening and communicative habits. Findings of this study also reveal that using mobile for English language learning makes the students, independent and self-evaluator.

Open access

Krzysztof Treder, Włodzimierz Przewodowski and Agnieszka Barnyk

Factors influencing detection of Potato Leafroll Virus and Potato Virus Y in potato tuber extracts

Detection of Potato leafroll virus (PLRV) and Potato virus Y (PVY) directly in potato tubers has been influenced by several factors. The most important were: the place of tuber sampling, preincubation of tuber sap before loading into wells of microplate and duration of tubers storage after collecting from field. The concentration of both viruses was highest in the heel part of tubers, whenever tested. Preincubation of tuber sap for several hours improved true/false signal ratio for dormant tubers and enabled reliable detection of both viruses. However after natural dormancy breaking it was necessary to change Cocktail-ELISA procedure to obtain reliable results, consistent with DAS-ELISA on leaves. The sap was not preincubated but loaded into wells directly after sample collecting and immuno-enzymatic reaction was developed overnight in refrigerator.

Open access

D. Wilk-Kołodziejczyk, A.S. Kluska-Nawarecka, K. Regulski, W. Adrian and K. Jaśkowiec

Abstract

The aim of this work was to propose a methodology supporting the task of collecting the comparative data on studies of the mechanical properties of ADI. Collecting of research data is an important step in the process of finding the optimum design solutions for newly made products - experimental data allow us properly calibrate the manufacturing process of ADI to let the final product achieve the required properties. Parameters of the ADI production process, i.e. the time and temperature of austenitising and austempering, as well as the alloying elements added to ductile iron affect the ADI properties. The design process can use research data collected, among others, from the Web. As stated in the article, the process of data acquisition can be supported by semantic technologies, including ontologies which are descriptive logic formalism.